Patent Publication Number: US-10786995-B2

Title: Ink delivery systems and methods

Description:
CROSS REFERENCE TO RELATED CASES 
     This application is a continuation of U.S. application Ser. No. 16/025,999, filed Jul. 2, 2018, which is a continuation of U.S. patent application Ser. No. 15/224,320, filed Jul. 29, 2016, (now U.S. Pat. No. 10,035,351, issued Jul. 31, 2018). U.S. application Ser. No. 15/224,320 claims benefit to U.S. Provisional Application No. 62/199,906, filed Jul. 31, 2015. Each of the aforementioned applications is incorporated herein by reference in its entirety. 
    
    
     OVERVIEW 
     Various embodiments of a printing system according to the present teachings can be useful for patterned area printing of substrates in the manufacture of a variety of devices and apparatuses in a wide range of technology areas, for example, but not limited by, OLED displays, OLED lighting, organic photovoltaics, Perovskite solar cells, and organic semiconductor circuits. 
     The non-limiting example of OLED display technologies presents a variety of fabrication challenges that can utilize the features of various embodiments of printing systems according to the present teachings. Interest in the potential of organic light-emitting diode (OLED) display technology has been driven by OLED display technology attributes that include demonstration of display panels that have highly saturated colors, are high-contrast, ultrathin, fast-responding, and energy efficient. Additionally, a variety of substrate materials, including flexible polymeric materials, can be used in the fabrication of OLED display technology. Though the demonstration of displays for small screen applications, primarily for cell phones, has served to emphasize the potential of the technology, challenges remain in scaling high volume manufacturing across a range of substrate formats in high yield. 
     With respect to scaling of formats, a Gen 5.5 substrate has dimensions of about 130 cm×150 cm and can yield about eight 26″ flat panel displays. In comparison, larger format substrates can include using Gen 7.5 and Gen 8.5 mother glass substrate sizes. A Gen 7.5 mother glass has dimensions of about 195 cm×225 cm, and can be cut into eight 42″ or six 47″ flat panel displays per substrate. The mother glass used in Gen 8.5 is approximately 220 cm×250 cm, and can be cut to six 55″ or eight 46″ flat panel displays per substrate. One indication of the challenges that remain in scaling of OLED display manufacturing to larger formats is that the high-volume manufacture of OLED displays in high yield on substrates larger than Gen 5.5 substrates has proven to be substantially challenging. 
     In principle, an OLED device may be manufactured by the printing of various organic thin films, as well as other materials, on a substrate using a printing system. Such organic materials can be susceptible to damage by oxidation and other chemical processes. Housing a printing system in a fashion that can be scaled for various substrate sizes and can be done in an inert, substantially low-particle printing environment can present a variety of engineering challenges. Manufacturing tools for high throughput large-format substrate printing, for example, such as printing of Gen 7.5 and Gen 8.5 substrates, require substantially large facilities. Accordingly, maintaining a large facility under an inert atmosphere, requiring gas purification to remove reactive atmospheric species, such as water vapor, oxygen and ozone, as well as organic solvent vapors, as well as maintaining a substantially low-particle printing environment, has proven to be significantly challenging. 
     As such, challenges remain in scaling high volume manufacturing for technologies that can utilize a controlled environment, across a range of substrate formats in high yield. Accordingly, there exists a need for various embodiments of a printing system that can be enclosed in an inert, substantially low-particle environment, and can be readily scaled on a variety of substrates sizes and substrate materials used in, for example, but not limited by, OLED display, OLED lighting, organic photovoltaics, Perovskite solar cells, and organic semiconductor circuit technologies. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       A better understanding of the features and advantages of the present disclosure will be obtained by reference to the accompanying drawings, which are intended to illustrate, not limit, the present teachings. In the drawings, which are not necessarily drawn to scale, like numerals may describe similar components in different views. Like numerals having different letter suffixes may represent different instances of similar components. 
         FIG. 1  illustrates generally a front perspective view of view of a gas enclosure assembly in accordance with various embodiments of the present teachings. 
         FIG. 2  illustrates generally an exploded view of various embodiments of a gas enclosure assembly as depicted in  FIG. 1 . 
         FIG. 3  is an expanded perspective view that illustrates generally the printing system depicted in  FIG. 2 . 
         FIG. 4  is an expanded perspective view that illustrates generally an auxiliary enclosure of a gas enclosure system according to various embodiments of the present teachings. 
         FIG. 5A  is a schematic representation of a local ink delivery system and a local waste assembly in flow communication with a bulk ink delivery system that illustrates generally various embodiments an enclosed printing system of the present teachings.  FIG. 5B  is an expanded view of a local ink delivery system of  FIG. 5A  in flow communication with a printhead device assembly.  FIG. 5C  is an expanded view of a local waste assembly in flow communication with a bulk ink delivery system. 
         FIG. 5D  is a schematic representation of a local ink delivery system and a local waste assembly in flow communication with a bulk ink delivery system that illustrates generally various embodiments an enclosed printing system of the present teachings. 
         FIG. 6A  and  FIG. 6B  are schematic representations of various components of an ink delivery system for an enclosed printing system that illustrate generally various embodiments of the present teachings. 
         FIG. 7  is a schematic representation of a bulk ink delivery system that illustrates generally various embodiments an enclosed printing system of the present teachings. 
         FIG. 8A  illustrates generally a bottom perspective view of a printhead device assembly mounted on an X-axis bridge for an enclosed printing system according to various embodiments of the present teachings.  FIG. 8B  illustrates generally an expanded bottom perspective view of a printhead device assembly as in  FIG. 8A . 
         FIG. 9  illustrates generally a bottom front perspective view of a printhead device according to various embodiments of the present teachings. 
         FIG. 10A  illustrates generally a perspective view of a printing system that includes a bulk ink delivery system and a local ink delivery system according to various embodiments of the present teachings.  FIG. 10B  is an expanded view of a portion of  FIG. 10A , as indicated in  FIG. 10A . 
         FIG. 11  illustrates generally a schematic view of various embodiments of gas enclosure assembly and related system components the present teachings. 
         FIG. 12A  and  FIG. 12B  are schematic views that illustrate generally various embodiments of an enclosed printing system and components for integrating and controlling gas sources such as can be used to establish a controlled gas environment in a gas enclosure. 
         FIG. 13A  and  FIG. 13B  are schematic views that illustrate generally various embodiments of an enclosed printing system and components for integrating and controlling gas sources such as can be used to establish a controlled gas environment in a gas enclosure. 
         FIG. 14  is a schematic view that illustrates generally components for integrating and controlling gas sources such as can be used to provide a gas source to various apparatuses in a printing system of the present teachings, as well as to establish a controlled gas environment in a gas enclosure. 
     
    
    
     DETAILED DESCRIPTION OF THE DISCLOSURE 
     The present teachings disclose various embodiments of a printing system for printing a substrate, in which the printing system can be housed in a gas enclosure, where the environment within the enclosure can be maintained as a controlled printing environment. A controlled environment of the present teachings can include control of the type of gas environment within the gas enclosure, the size and level particulate matter within the enclosure, control of the temperature within the enclosure and control of lighting. Various embodiments of a printing system of the present teachings can include a bulk ink delivery system that can be external to a gas enclosure. A bulk ink delivery system according to the present teachings can supply ink to a local ink delivery system that is internal to the gas enclosure. Various embodiments of a local ink delivery system of the present teachings can be proximal to a printhead device assembly, and can include a two-stage ink supply having a local ink replenishment reservoir that is configured to supply ink to a local ink dispensing reservoir to a constant level. According to the present teachings, a local ink dispensing reservoir can be in flow communication with a plurality of printhead devices. As such, a two-stage local ink delivery system maintaining a constant level in a local ink dispensing reservoir can provide constant head pressure to the plurality of printhead devices. 
     Various embodiments of a gas enclosure assembly can be sealably constructed and integrated with various components that provide a gas circulation and filtration system, a particle control system, a gas purification system, and a thermal regulation system and the like to form various embodiments of a gas enclosure system that can sustain an inert gas environment that is substantially low-particle for processes requiring such an environment. Various embodiments of a gas enclosure can have a printing system enclosure and an auxiliary enclosure constructed as a section of a gas enclosure assembly, which can be sealably isolated from the printing system enclosure of a gas enclosure. Various embodiments of a printing system of the present teachings can have a printhead management system enclosed in an auxiliary enclosure. Embodiments of printhead management system of the present teachings can include various devices and apparatuses for maintenance and calibration of a printhead; the various devices and apparatuses each mounted on a motion system platform for the fine positioning of the various devices and apparatuses relative to a printhead. 
     A printing system, such as printing system  2000  of  FIG. 2 , shown in expanded view in  FIG. 3 , can be comprised of several devices and apparatuses, which allow the reliable placement of ink drops onto specific locations on a substrate. Printing requires relative motion between the printhead device assembly that can include a plurality of printheads and the substrate. This can be accomplished with a motion system, typically a gantry or split axis XYZ system. Either the printhead device assembly can move over a stationary substrate (gantry style), or both the printhead and substrate can move, in the case of a split axis configuration. In another embodiment, a printhead device assembly can be substantially stationary; for example, in the X and Y axes, and the substrate can move in the X and Y axes relative to the printheads, with Z axis motion provided either by a substrate support apparatus or by a Z-axis motion system associated with a printhead device assembly. As the printheads move relative to the substrate, droplets of ink are ejected at the correct time to be deposited in the desired location on a substrate. A substrate can be inserted and removed from the printer using a substrate loading and unloading system. Depending on the printer configuration, this can be accomplished with a mechanical conveyor, a substrate floatation table with a conveyance assembly, or a substrate transfer robot with end effector. For various embodiments of systems and methods of the present teachings, an Y-axis motion system can be based on an air-bearing gripper system. 
     For clearer perspective regarding substrate sizes that can be used in manufacturing of various display devices, generations of mother glass substrate sizes have been undergoing evolution for flat panel displays fabricated by other-than OLED printing since about the early 1990s. The first generation of mother glass substrates, designated as Gen 1, is approximately 30 cm×40 cm, and therefore could produce a  15 ″ panel. Around the mid-1990s, the existing technology for producing flat panel displays had evolved to a mother glass substrate size of Gen 3.5, which has dimensions of about 60 cm×72 cm. In comparison, a Gen 5.5 substrate has dimensions of about 130 cm×150 cm. 
     As generations have advanced, mother glass sizes for Gen 7.5 and Gen 8.5 are in production for other-than OLED printing fabrication processes. A Gen 7.5 mother glass has dimensions of about 195 cm×225 cm, and can be cut into eight 42″ or six 47″ flat panels per substrate. The mother glass used in Gen 8.5 is approximately 220×250 cm, and can be cut to six 55″ or eight 46″ flat panels per substrate. The promise of OLED flat panel display technologies for qualities such as truer color, higher contrast, thinness, flexibility, transparency, and energy efficiency have been realized, at the same time that OLED manufacturing is practically limited to G 3.5 and smaller. Currently, OLED printing is believed to be the optimal manufacturing technology to break this limitation and enable OLED panel manufacturing for not only mother glass sizes of Gen 3.5 and smaller, but at the largest mother glass sizes, such as Gen 5.5, Gen 7.5, and Gen 8.5. One of the features of OLED panel display technology includes that a variety of substrate materials can be used, for example, but not limited by, a variety of glass substrate materials, as well as a variety of polymeric substrate materials. In that regard, sizes recited from the terminology arising from the use of glass-based substrates can be applied to substrates of any material suitable for use in OLED printing. 
     Manufacturing tools that in principle can allow for the printing of a variety of substrate sizes that includes large-format substrate sizes, can require substantially large facilities for housing such manufacturing tools. Accordingly, maintaining an entire large facility under an inert atmosphere presents engineering challenges, such as continual purification of a large volume of an inert gas. Various embodiments of a gas enclosure system can have a circulation and filtration system internal a gas enclosure assembly in conjunction with a gas purification system external a gas enclosure that together can provide continuous circulation of a substantially low-particulate inert gas having substantially low levels of reactive species throughout a gas enclosure system. According to the present teachings, an inert gas may be any gas that does not undergo a chemical reaction under a defined set of conditions. Some commonly used non-limiting examples of an inert gas can include nitrogen, any of the noble gases, and any combination thereof. Additionally, providing a large facility that is essentially hermetically sealed to prevent contamination of various reactive atmospheric gases, such as water vapor, oxygen and ozone, as well as organic solvent vapors generated from various printing process poses an engineering challenge. According to the present teachings, a printing facility would maintain levels for each species of various reactive species, including various reactive atmospheric gases, such as water vapor, oxygen and ozone, as well as organic solvent vapors at 100 ppm or lower, for example, at 10 ppm or lower, at 1.0 ppm or lower, or at 0.1 ppm or lower. 
     The need for printing an OLED panel in a facility in which the levels of each of a reactive species should be maintained at targeted low levels can be illustrated in reviewing the information summarized in Table 1. The data summarized on Table 1 resulted from the testing of each of a test coupon comprising organic thin film compositions for each of red, green, and blue, fabricated in a large-pixel, spin-coated device format. Such test coupons are substantially easier to fabricate and test for the purpose of rapid evaluation of various formulations and processes. Though test coupon testing should not be confused with lifetime testing of a printed panel, it can be indicative of the impact of various formulations and processes on lifetime. The results shown in the table below represent variation in the process step in the fabrication of test coupons in which only the spin-coating environment varied for test coupons fabricated in a nitrogen environment where reactive species were less than 1 ppm compared to test coupons similarly fabricated but in air instead of a nitrogen environment. 
     It is evident through the inspection of the data in Table 1 for test coupons fabricated under different processing environments, particularly in the case of red and blue, that printing in an environment that effectively reduces exposure of organic thin film compositions to reactive species may have a substantial impact on the stability of various ELs, and hence on lifetime. The lifetime specification is of particular significance for OLED panel technology, as this correlates directly to display product longevity; a product specification for all panel technologies, which has been challenging for OLED panel technology to meet. In order to provide panels meeting requisite lifetime specifications, levels of each of a reactive species, such as water vapor, oxygen, and ozone, as well as organic solvent vapors, can be maintained at 100 ppm or lower, for example, at 10 ppm or lower, at 1.0 ppm or lower, or at 0.1 ppm or lower with various embodiments of a gas enclosure system of the present teachings. 
     
       
         
           
               
             
               
                 TABLE 1 
               
             
            
               
                   
               
               
                 Impact of inert gas processing on lifetime for OLED panels 
               
            
           
           
               
               
               
               
               
               
               
               
            
               
                   
                   
                 V 
                   
                   
                   
                   
                   
               
               
                   
                 Process 
                 @ 10 
                 Cd/A 
                 CIE (x, y) 
                 T95 
                 T80 
                 T50 
               
            
           
           
               
               
               
               
            
               
                 Color 
                 Environment 
                 mA/cm 2   
                 @ 1000 Cd/m 2   
               
               
                   
               
            
           
           
               
               
               
               
               
               
               
               
            
               
                 Red 
                 Nitrogen 
                 6 
                 9 
                 (0.61, 0.38) 
                 200 
                 1750 
                 10400 
               
               
                   
                 Air 
                 6 
                 8 
                 (0.60, 0.39) 
                 30 
                 700 
                 5600 
               
               
                 Green 
                 Nitrogen 
                 7 
                 66 
                 (0.32, 0.63) 
                 250 
                 3700 
                 32000 
               
               
                   
                 Air 
                 7 
                 61 
                 (0.32, 0.62) 
                 250 
                 2450 
                 19700 
               
               
                 Blue 
                 Nitrogen 
                 4 
                 5 
                 (0.14, 0.10) 
                 150 
                 750 
                 3200 
               
               
                   
                 Air 
                 4 
                 5 
                 (0.14, 0.10) 
                 15 
                 250 
                 1800 
               
               
                   
               
            
           
         
       
     
     In addition to providing an inert environment, maintaining a substantially low-particle environment for OLED printing is of particular importance, as even very small particles can lead to a visible defect on an OLED panel. Particle control in a gas enclosure system can present significant challenges not presented for processes that can be done, for example, in atmospheric conditions under open air, high flow laminar flow filtration hoods. For example, of a manufacturing facility can require a substantial length of various service bundles that can be operatively connected from various systems and assemblies to provide optical, electrical, mechanical, and fluidic connections required to operate, for example, but not limited by, a printing system. Such service bundles used in the operation of a printing system and located proximal to a substrate positioned for printing can be an ongoing source of particulate matter. Additionally, components used in a printing system, such as fans or linear motion systems that use friction bearing, can be particle generating components. Various embodiments of a gas circulation and filtration system of the present teachings can be used in conjunction with particle control components to contain and exhaust particulate matter. Additionally, by using a variety of intrinsically low-particle generating pneumatically operated components, such as, but not limited by, substrate floatation tables, air bearings, and pneumatically operated robots, and the like, a low particle environment for various embodiments of a gas enclosure system can be maintained. 
     Regarding maintaining a substantially low-particle environment, various embodiments of a gas circulation and filtration system can be designed to provide a low particle inert gas environment for airborne particulates meeting the standards of International Standards Organization Standard (ISO) 14644-1:1999, “Cleanrooms and associated controlled environments—Part 1: Classification of air cleanliness,” as specified by Class 1 through Class 5. However, controlling airborne particulate matter alone is not sufficient for providing a low-particle environment proximal to a substrate during, for example, but not limited by, a printing process, as particles generated proximal to a substrate during such a process can accumulate on a substrate surface before they can be swept through a gas circulation and filtration system. 
     Accordingly, in conjunction with a gas circulation and filtration system, various embodiments of a gas enclosure system of the present teachings can have a particle control system that can include components that can provide a low-particle zone proximal to a substrate during processing in a printing step. A particle control system for various embodiments of a gas enclosure system of the present teachings can include a gas circulation and filtration system, a low-particle-generating X-axis linear bearing system for moving a printhead device assembly relative to a substrate, a service bundle housing exhaust system, and a printhead device assembly exhaust system. For example, a gas enclosure system can have a gas circulation and filtration system internal a gas enclosure assembly. 
     Various embodiments of systems and methods of the present teachings can maintain a substantially low-particle environment providing for an average on-substrate distribution of particles of a particular size range of interest that does not exceed an on-substrate deposition rate specification. An on-substrate deposition rate specification can be set for each of a particle size range of interest of between about 0.1 □m and greater to about 10 □m and greater. In various embodiments systems and methods of the present teachings, an on-substrate particle deposition rate specification can be expressed as a limit of the number of particles deposited per square meter of substrate per minute for each of a target particle size range. 
     Various embodiments of an on-substrate particle deposition rate specification can be readily converted from a limit of the number of particles deposited per square meter of substrate per minute to a limit of the number of particles deposited per substrate per minute for each of a target particle size range. Such a conversion can be readily done through a known relationship between substrates, for example, of a specific generation-sized substrate and the corresponding area for that substrate generation. For example, Table 2 below summarizes aspect ratios and areas for some known generation-sized substrates. It should be understood that a slight variation of aspect ratio and hence size may be seen from manufacturer to manufacturer. However, regardless of such variation, a conversion factor for a specific generation-sized substrate and an area in square meters can be obtained any of a variety of generation-sized substrates. 
     
       
         
           
               
             
               
                 TABLE 2 
               
             
            
               
                   
               
               
                 Correlation between area and substrate size 
               
            
           
           
               
               
               
               
               
            
               
                   
                 Generation ID 
                 X (mm) 
                 Y (mm) 
                 Area (m2) 
               
               
                   
                   
               
            
           
           
               
               
               
               
               
            
               
                   
                 Gen 3.0 
                 550 
                 650 
                 0.36 
               
               
                   
                 Gen 3.5 
                 610 
                 720 
                 0.44 
               
               
                   
                 Gen 3.5 
                 620 
                 750 
                 0.47 
               
               
                   
                 Gen 4 
                 680 
                 880 
                 0.60 
               
               
                   
                 Gen 4 
                 730 
                 920 
                 0.67 
               
               
                   
                 Gen 5 
                 1100 
                 1250 
                 1.38 
               
               
                   
                 Gen 5 
                 1100 
                 1300 
                 1.43 
               
               
                   
                 Gen 5.5 
                 1300 
                 1500 
                 1.95 
               
               
                   
                 Gen 6 
                 1500 
                 1850 
                 2.78 
               
               
                   
                 Gen 7.5 
                 1950 
                 2250 
                 4.39 
               
               
                   
                 Gen 8 
                 2160 
                 2400 
                 5.18 
               
               
                   
                 Gen 8 
                 2160 
                 2460 
                 5.31 
               
               
                   
                 Gen 8.5 
                 2200 
                 2500 
                 5.50 
               
               
                   
                 Gen 9 
                 2400 
                 2800 
                 6.72 
               
               
                   
                 Gen 10 
                 2850 
                 3050 
                 8.69 
               
               
                   
                   
               
            
           
         
       
     
     Additionally, an on-substrate particle deposition rate specification expressed as a limit of the number of particles deposited per square meter of substrate per minute can be readily converted to any of a variety of unit time expressions. It will be readily understood that an on-substrate particle deposition rate specification normalized to minutes can be readily converted to any other expression of time through know relationships of time, for example, but not limited by, such as second, hour, day, etc. Additionally, units of time specifically relating to processing can be used. For example, a print cycle can be associated with a unit of time. For various embodiments of a gas enclosure system according to the present teachings a print cycle can be a period of time in which a substrate is moved into a gas enclosure system for printing and then removed from a gas enclosure system after printing is complete. For various embodiments of a gas enclosure system according to the present teachings a print cycle can be a period of time from the initiation of the alignment of a substrate with respect to a printhead device assembly to the delivery of a last ejected drop of ink onto the substrate. In the art of processing, total average cycle time or TACT can be an expression of a unit of time for a particular process cycle. According to various embodiments of systems and methods of the present teachings, TACT for a print cycle can be about 30 seconds. For various embodiments of systems and methods of the present teachings, TACT for a print cycle can be about 60 seconds. In various embodiments of systems and methods of the present teachings, TACT for a print cycle can be about 90 seconds. For various embodiments of systems and methods of the present teachings, TACT for a print cycle can be about 120 seconds. In various embodiments of systems and methods of the present teachings, TACT for a print cycle can be about 300 seconds. 
     With respect to airborne particulate matter and particle deposition within a system, a substantial number of variables can impact developing a general model that may adequately compute, for example, an approximation of a value for particle fallout rate on a surface, such as a substrate, for any particular manufacturing system. Variables such as the size of particles, the distribution of particles of particular size; surface area of a substrate and the time of exposure of a substrate within a system can vary depending on various manufacturing systems. For example, the size of particles and the distribution of particles of particular size can be substantially impacted by the source and location of particle-generating components in various manufacturing systems. Calculations based on various embodiments of gas enclosure systems of the present teachings suggest that without various particle control systems of the present teachings, on-substrate deposition of particulate matter per print cycle per square meter of substrate can be between more than about 1 million to more than about 10 million particles for particles in a size range of 0.1 □m and greater. Such calculations suggest that that without various particle control systems of the present teachings, on-substrate deposition of particulate matter per print cycle per square meter of substrate can be between more than about 1000 to about more than about 10,000 particles for particles in a size range of about 2 □m and greater. 
     Various embodiments of a low-particle gas enclosure system of the present teachings can maintain a low-particle environment providing for an average on-substrate particle distribution that meets an on-substrate deposition rate specification of less than or equal to about 100 particles per square meter of substrate per minute for particles greater than or equal to 10 □m in size. Various embodiments of a low-particle gas enclosure system of the present teachings can maintain a low-particle environment providing for an average on-substrate particle distribution that meets an on-substrate deposition rate specification of less than or equal to about 100 particles per square meter of substrate per minute for particles greater than or equal to 5 □m in size. In various embodiments of a gas enclosure system of the present teachings, a low-particle environment can be maintained providing for an average on-substrate particle distribution that meets an on-substrate deposition rate specification of less than or equal to about 100 particles per square meter of substrate per minute for particles greater than or equal to 2 □m in size. In various embodiments of a gas enclosure system of the present teachings, a low-particle environment can be maintained providing for an average on-substrate particle distribution that meets an on-substrate deposition rate specification of less than or equal to about 100 particles per square meter of substrate per minute for particles greater than or equal to 1 □m in size. Various embodiments of a low-particle gas enclosure system of the present teachings can maintain a low-particle environment providing for an average on-substrate particle distribution that meets an on-substrate deposition rate specification of less than or equal to about 1000 particles per square meter of substrate per minute for particles greater than or equal to 0.5 □m in size. For various embodiments of a gas enclosure system of the present teachings, a low-particle environment can be maintained providing for an average on-substrate particle distribution that meets an on-substrate deposition rate specification of less than or equal to about 1000 particles per square meter of substrate per minute for particles greater than or equal to 0.3 □m in size. Various embodiments of a low-particle gas enclosure system of the present teachings can maintain a low-particle environment providing for an average on-substrate particle distribution that meets an on-substrate deposition rate specification of less than or equal to about 1000 particles per square meter of substrate per minute for particles greater than or equal to 0.1 □m in size. 
     It is contemplated that a wide variety of ink formulations can be printed within the inert, substantially low-particle environment of various embodiments of a gas enclosure system of the present teachings. During the manufacture of an OLED display, an OLED pixel can be formed to include an OLED film stack, which can emit light of a specific peak wavelength when a voltage is applied. An OLED film stack structure between an anode and a cathode can include a hole injection layer (HIL), a hole transport layer (HTL), an emissive layer (EL), an electron transport layer (ETL) and an electron injection layer (EIL). In some embodiments of an OLED film stack structure, an electron transport layer (ETL) can be combined with an electron injection layer (EIL) to form an ETL/EIL layer. According to the present teachings, various ink formulations for an EL for various color pixel EL films of an OLED film stack can be printed using, for example, inkjet printing. Additionally, for example, but not limited by, the HIL, HTL, EML, and ETL/EIL layers can have ink formulations that can be printed using inkjet printing. 
     It is further contemplated that an organic encapsulation layer can be printed on a substrate printing. It is contemplated that an organic encapsulation layer can be printed using inkjet printing, as inkjet printing can provide several advantages. First, a range of vacuum processing operations can be eliminated because such inkjet-based fabrication can be performed at atmospheric pressure. Additionally, during an inkjet printing process, an organic encapsulation layer can be localized to cover portions of an OLED substrate over and proximal to an active region, to effectively encapsulate an active region, including lateral edges of the active region. The targeted patterning using inkjet printing results in eliminating material waste, as well as eliminating additional processing typically required to achieve patterning of an organic layer. An encapsulation ink can comprise a polymer including, for example, but not limited by, an acrylate, methacrylate, urethane, or other material, as well as copolymers and mixtures thereof, which can be cured using thermal processing (e.g. bake), UV exposure, and combinations thereof. As used herein polymer and copolymer can include any form of a polymer component that can be formulated into an ink and cured on a substrate to form an organic encapsulation layer. Such polymeric components can include polymers, and copolymers, as well as precursors thereof, for example, but not limited by, monomers, oligomers, and resins. 
     Various embodiments of a gas enclosure assembly can have various frame members that are constructed to provide contour for a gas enclosure assembly. Various embodiments of a gas enclosure assembly of the present teachings can accommodate a printing system, while optimizing the working space to minimize inert gas volume, and also allowing ready access to a printing system from the exterior during processing. In that regard, various gas enclosure assemblies of the present teachings can have a contoured topology and volume. As will be discussed in more detail subsequently herein, various embodiments of a gas enclosure can be contoured around a printing system base, upon which a substrate support apparatus can be mounted. Further, a gas enclosure can be contoured around a bridge structure of a printing system used for the X-axis movement of a carriage assembly. As a non-limiting example, various embodiments of a contoured gas enclosure according to the present teachings can have a gas enclosure volume of between about 6 m 3  to about 95 m 3  for housing various embodiments of a printing system capable of printing substrate sizes from Gen 3.5 to Gen 10. By way a further non-limiting example, various embodiments of a contoured gas enclosure according to the present teachings can have a gas enclosure volume of between about 15 m 3  to about 30 m 3  for housing various embodiments of a printing system capable of printing, for example, Gen 5.5 to Gen 8.5 substrate sizes. Such embodiments of a contoured gas enclosure can be between about 30% to about 70% savings in volume in comparison to a non-contoured enclosure having non-contoured dimensions for width, length and height. 
       FIG. 1  depicts a perspective view gas enclosure assembly  1000  in accordance with various embodiments of a gas enclosure assembly of the present teachings. Gas enclosure assembly  1000  can include front panel assembly  1200 , middle panel assembly  1300  and rear panel assembly  1400 . Front panel assembly  1200  can include front ceiling panel assembly  1260 , front wall panel assembly  1240 , which can have opening  1242  for receiving a substrate, and front base panel assembly  1220 . Rear panel assembly  1400  can include rear ceiling panel assembly  1460 , rear wall panel assembly  1440  and rear base panel assembly  1420 . Middle panel assembly  1300  can include first middle enclosure panel assembly  1340 , middle wall and ceiling panel assembly  1360  and second middle enclosure panel assembly  1380 , as well as middle base panel assembly  1320 . 
     Additionally, as depicted in  FIG. 1 , middle panel assembly  1300  can house a first printhead management system within auxiliary enclosure  1330  system as well as a second printhead management system in auxiliary enclosure  1380 . Such auxiliary enclosures can provide a controlled environment which can be the same or different from that of the remaining printing system enclosure portion of a gas enclosure housing of the present teachings. For example, various embodiments of an auxiliary enclosure can provide a substantially inert, low particle environment for housing various embodiments of a printhead management system. Various embodiments of an auxiliary enclosure constructed as a section of a gas enclosure assembly can be sealably isolated from the working volume of a gas enclosure system. For various embodiments of systems and methods of the present teachings, an auxiliary enclosure can be less than or equal to about 1% of the enclosure volume of a gas enclosure system. In various embodiments of systems and methods of the present teachings, an auxiliary enclosure can be can be less than or equal to about 2% of the enclosure volume of a gas enclosure system. For various embodiments of systems and methods of the present teachings, an auxiliary enclosure can be less than or equal to about 5% of the enclosure volume of a gas enclosure system. In various embodiments of systems and methods of the present teachings, an auxiliary enclosure can be less than or equal to about 10% of the enclosure volume of a gas enclosure system. In various embodiments of systems and methods of the present teachings, an auxiliary enclosure can be less than or equal to about 20% of the enclosure volume of a gas enclosure system. Should the opening of an auxiliary enclosure to an ambient environment containing reactive gases be indicated for performing, for example, a maintenance procedure, isolating an auxiliary enclosure from the working volume of a gas enclosure can prevent contamination of the entire volume of a gas enclosure. Further, given the relatively small volume of an auxiliary enclosure in comparison to the printing system enclosure portion of a gas enclosure, the recovery time for an auxiliary enclosure can take significantly less time than recovery time for an entire printing system enclosure. 
     As depicted in  FIG. 2 , gas enclosure assembly  1000  can include front base panel assembly  1220 , middle base panel assembly  1320 , and rear base panel assembly  1420 , which when fully-constructed form a contiguous base or pan on which printing system  2000  can be mounted. In a similar fashion as described for gas enclosure assembly  100  of  FIG. 1 , the various frame members and panels comprising front panel assembly  1200 , middle panel assembly  1300 , and rear panel assembly  1400  of gas enclosure assembly  1000  can be joined around printing system  2000  to form a printing system enclosure. Front panel assembly  1200  can be contoured around printing system  2000  mounted to form a first tunnel enclosure section of a gas enclosure. Similarly, rear panel assembly  1400  can be contoured around printing system  2000  to form a second tunnel enclosure section of a gas enclosure. Additionally, middle panel assembly  1300  can be contoured around a bridge section of a printing system  2000  to form a bridge enclosure section of a gas enclosure. Together, a first tunnel enclosure section, a second tunnel section and a bridge enclosure section can form a printing system enclosure. As will be discussed in more detail herein, according to the present teachings, an auxiliary enclosure can be sealably isolated from a printing system enclosure during, for example, a printing process for performing various measurement and maintenance tasks, with little or no interruption to the printing process. 
     Further, a fully constructed gas enclosure assembly, such as gas enclosure assembly  1000 , when integrated with various environmental control systems can form various embodiments of a gas enclosure system including various embodiments of a printing system, such as printing system  2000 . According to various embodiments of a gas enclosure system of the present teachings, environmental control of an interior volume defined by a gas enclosure assembly can include control of lighting, for example, by the number and placement of lights of a specific wavelength, control of particulate matter using various embodiments of a particle control system, control of reactive gas species using various embodiments of a gas purification system, and temperature control of a gas enclosure assembly using various embodiments of a thermal regulation system. 
     A printing system, such as printing system  2000  of  FIG. 2 , shown in expanded view in  FIG. 3 , can be comprised of several devices and apparatuses, which allow the reliable placement of ink drops onto specific locations on a substrate. These devices and apparatuses can include, but are not limited to, a printhead device assembly, ink delivery system, a motion system for providing relative motion between a printhead device assembly and a substrate, substrate support apparatus, substrate loading and unloading system, and printhead management system. 
     A printhead device assembly can include at least one inkjet head, with at least one orifice capable of ejecting droplets of ink at a controlled rate, velocity, and size. The inkjet head is fed by an ink supply system which provides ink to the inkjet head. As shown in an expanded view of  FIG. 3 , printing system  2000  can have a substrate, such as substrate  2050 , which can be supported by a substrate support apparatus, such as a chuck, for example, but not limited by, a vacuum chuck, a substrate floatation chuck having pressure ports, and a substrate floatation chuck having vacuum and pressure ports. In various embodiments of systems and methods of the present teachings, a substrate support apparatus can be a substrate floatation table. As will be discussed in more detail subsequently herein, substrate floatation table  2200  of  FIG. 3  can be used for supporting substrate  2050 , and in conjunction with a Y-axis motion system, can be part of a substrate conveyance system providing for the frictionless conveyance of substrate  2050 . A Y-axis motion system of the present teachings can include first Y-axis support beam  2351  and second Y-axis support beam  2352 , which can include a gripper system (not shown) for holding a substrate, as will be discussed in more detail herein. Y-axis motion can be provided by either a linear air bearing or linear mechanical system. Substrate floatation table  2200  of printing system  2000  shown in  FIG. 2  and  FIG. 3  can define the travel of substrate  2050  through gas enclosure assembly  1000  of  FIG. 1  during a printing process. 
       FIG. 3  illustrates generally an example of substrate floatation table  2200  for a printing system  2000  that can include a floating conveyance of a substrate, which can have a porous medium to provide floatation. In the example of  FIG. 3 , a handler or other conveyance can be used to position a substrate  2050  in an input region  2201  of a substrate floatation table  2200 , such as located on a conveyor. The conveyer can position the substrate  2050  at a specified location within the printing system such as using either mechanical contact (e.g., using an array of pins, a tray, or a support frame configuration), or using gas cushion to controllably float the substrate  2050  (e.g., an “air bearing” table configuration). A printing region  2202  of the substrate floatation table  2200  can be used to controllably deposit one or more layers on the substrate  2050  during fabrication. The printing region  2202  can also be coupled to an output region  2203  of the substrate floatation table  2200 . The conveyer can extend along the input region  2201 , the printing region  2202 , and the output region  2203  of the substrate floatation table  2200 , and the substrate  2050  can be repositioned as desired for various deposition tasks, or during a single deposition operation. The controlled environments nearby the input region  2201 , the printing region  2202 , and the output region  2203  can be commonly-shared. 
     The printing system  2000  of  FIG. 3  can include one or more printhead devices  2505 , each printhead device having one or more printheads; e.g. nozzle printing, thermal jet or ink-jet type. The one or more printhead devices  2505  can be coupled to or otherwise traversing an overhead carriage, such as first X-axis carriage assembly  2301 . For various embodiments of printing system  2000  of the present teachings, one or more printheads of one or more printhead devices  2505  can be configured to deposit one or more patterned organic layers on the substrate  2050  in a “face up” configuration of the substrate  2050 . Such layers can include one or more of an electron injection or transport layer, a hole injection or transport layer, a blocking layer, or an emission layer, for example. Such materials can provide one or more electrically functional layers. 
     According to the floatation schemes shown in  FIG. 3 , in an example where the substrate  2050  is supported exclusively by the gas cushion, a combination of positive gas pressure and vacuum can be applied through the arrangement of ports or using a distributed porous medium. Such a zone having both pressure and vacuum control can effectively provide a fluidic spring between the conveyor and a substrate. A combination of positive pressure and vacuum control can provide a fluidic spring with bidirectional stiffness. The gap that exists between the substrate (e.g., substrate  2050 ) and a surface can be referred to as the “fly height,” and such a height can be controlled or otherwise established by controlling the positive pressure and vacuum port states. In this manner, the substrate Z-axis height can be carefully controlled in, for example, the printing region  2202 . In some embodiments, mechanical retaining techniques, such as pins or a frame, can be used to restrict lateral translation of the substrate while the substrate is supported by the gas cushion. Such retaining techniques can include using spring loaded structures, such as to reduce the instantaneous forces incident the sides of the substrate while the substrate is being retained; this can be beneficial as a high force impact between a laterally translating substrate and a retaining means can cause substrate chipping or even catastrophic breakage. 
     Elsewhere, as illustrated generally in  FIG. 3 , such as where the fly height need not be controlled precisely, pressure-only floatation zones can be provided, such as along the conveyor in the input or output regions  2100  or  2300 , or elsewhere. A “transition” zone can be provided such as where a ratio of pressure to vacuum nozzles increases or decreases gradually. In an illustrative example, there can be an essentially uniform height between a pressure-vacuum zone, a transition zone, and a pressure only zone, so that within tolerances, the three zones can lie essentially in one plane. A fly height of a substrate over pressure-only zones elsewhere can be greater than the fly height of a substrate over a pressure-vacuum zone, such as in order to allow enough height so that a substrate will not collide with a floatation table in the pressure-only zones. In an illustrative example, an OLED panel substrate can have a fly height of between about 150 micrometers □□□□□ to about 300□ above pressure-only zones, and then between about 30□ to about 50□ above a pressure-vacuum zone. In an illustrative example, one or more portions of the substrate floatation table  2200  or other fabrication apparatus can include an “air bearing” assembly provided by NewWay® Air Bearings (Aston, Pa., United States of America). 
     A porous medium can be used to establish a distributed pressurized gas cushion for floating conveyance or support of the substrate  2050  during one or more of printing, buffering, drying, or thermal treatment. For example, a porous medium “plate” such as coupled to or included as a portion of a conveyor can provide a “distributed” pressure to support the substrate  2050  in a manner similar to the use of individual gas ports. The use of a distributed pressurized gas cushion without using large gas port apertures can in some instances further improve uniformity and reduce or minimize the formation of mura or other visible defects, such as in those instances where the use of relatively large gas ports to create a gas cushion leads to non-uniformity, in spite of the use of a gas cushion. 
     A porous medium can be obtained such as from Nano TEM Co., Ltd. (Niigata, Japan), such as having physical dimensions specified to occupy an entirety of the substrate  2050 , or specified regions of the substrate such as display regions or regions outside display regions. Such a porous medium can include a pore size specified to provide a desired pressurized gas flow over a specified area, while reducing or eliminating mura or other visible defect formation. 
     Printing requires relative motion between the printhead device assembly and the substrate. This can be accomplished with a motion system, typically a gantry or split axis XYZ system. Either the printhead device assembly can move over a stationary substrate (gantry style), or both the printhead and substrate can move, in the case of a split axis configuration. In another embodiment, a printhead device assembly can be substantially stationary; for example, in the X and Y axes, and the substrate can move in the X and Y axes relative to the printheads, with Z axis motion provided either by a substrate support apparatus or by a Z-axis motion system associated with a printhead device assembly. As the printheads move relative to the substrate, droplets of ink are ejected at the correct time to be deposited in the desired location on a substrate. A substrate can be inserted and removed from the printer using a substrate loading and unloading system. Depending on the printer configuration, this can be accomplished with a mechanical conveyor, a substrate floatation table with a conveyance assembly, or a substrate transfer robot with end effector. A printhead management system can be comprised of several subsystems which allow for such measurement tasks, such as the checking for nozzle firing, as well as the measurement of drop volume, velocity and trajectory from every nozzle in a printhead, and maintenance tasks, such as wiping or blotting the inkjet nozzle surface of excess ink, priming and purging a printhead by ejecting ink from an ink supply through the printhead and into a waste basin, and replacement of printheads. Given the variety of components that can comprise a printing system, various embodiments of printing systems can have a variety of footprints and form factors. 
     With respect to  FIG. 3 , printing system base  2100 , can include first riser  2120  and second riser  2122 , upon which bridge  2130  is mounted. For various embodiments of printing system  2000 , bridge  2130  can support first X-axis carriage assembly  2301  and second X-axis carriage assembly  2302 , which can control the movement of first printhead device assembly  2501  and second printhead device assembly  2502 , respectively across bridge  2130 . For various embodiments of printing system  2000 , first X-axis carriage assembly  2301  and second X-axis carriage assembly  2302  can utilize a linear air bearing motion system, which are intrinsically low-particle generating. According to various embodiments of a printing system of the present teachings, an X-axis carriage can have a Z-axis moving plate mounted thereupon. In  FIG. 3 , first X-axis carriage assembly  2301  is depicted with first Z-axis moving plate  2310 , while second X-axis carriage assembly  2302  is depicted with second Z-axis moving plate  2312 . Though  FIG. 3  depicts two carriage assemblies and two printhead device assemblies, for various embodiments of printing system  2000 , there can be a single carriage assembly and a single printhead device assembly. For example, either of first printhead device assembly  2501  and second printhead device assembly  2502  can be mounted on an X,Z-axis carriage assembly, while a camera system for inspecting features of substrate  2050  can be mounted on a second X,Z-axis carriage assembly. Various embodiments of printing system  2000  can have a single printhead device assembly, for example, either of first printhead device assembly  2501  and second printhead device assembly  2502  can be mounted on an X,Z-axis carriage assembly, while a UV lamp for curing an encapsulation layer printed on substrate  2050  can be mounted on a second X,Z-axis carriage assembly. For various embodiments of printing system  2000 , there can be a single printhead device assembly, for example, either of first printhead device assembly  2501  and second printhead device assembly  2502 , mounted on an X,Z-axis carriage assembly, while a heat source for curing an encapsulation layer printed on substrate  2050  can be mounted on a second carriage assembly. 
     In  FIG. 3 , each printhead device assembly, such as first printhead device assembly  2501  and second printhead device assembly  2502  of  FIG. 3 , can have a plurality of printheads mounted in at least one printhead device, as depicted in partial view for first printhead device assembly  2501 , which depicts a plurality of printhead devices  2505 . A printhead device can include, for example, but not limited by, fluidic and electronic connections to at least one printhead; each printhead having a plurality of nozzles or orifices capable of ejecting ink at a controlled rate, velocity and size. For various embodiments of printing system  2000 , a printhead device assembly can include between about 1 to about 60 printhead devices, where each printhead device can have between about 1 to about 30 printheads in each printhead device. A printhead, for example, an industrial inkjet head, can have between about 16 to about 2048 nozzles, which can expel a droplet volume of between about 0.1 pL to about 200 pL. 
     According to various embodiments of a gas enclosure system of the present teachings, given the sheer number of printhead devices and printheads, first printhead management system  2701  and second printhead management system  2702  can be housed in an auxiliary enclosure, which can be isolated from a printing system enclosure during a printing process for performing various measurement and maintenance tasks with little or no interruption to the printing process. As can be seen in  FIG. 3 , first printhead device assembly  2501  can be seen positioned relative to first printhead management system  2701  for ready performance of various measurement and maintenance procedures that can be performed by first printhead management system apparatuses  2707 ,  2709  and  2711 . Apparatuses  2707 ,  2709 , and  2011  can be any of a variety of subsystems or modules for performing various printhead management functions. For example, apparatuses  2707 ,  2709 , and  2011  can be any of a drop measurement module, a printhead replacement module, a purge basin module, and a blotter module. As depicted in  FIG. 3 , first printhead management system  2701  can have apparatuses  2707 ,  2709  and  2711 , which can be mounted on linear rail motion system  2705  for positioning relative to first printhead device assembly  2501 . Similarly, various apparatuses housed within second printhead management system  2702  can be mounted on linear rail motion system  2706  for positioning relative to first printhead device assembly  2502 . 
     With respect to various embodiments of a gas enclosure assembly having an auxiliary enclosure that can be closed off from, as well as sealably isolated from a first working volume, for example, a printing system enclosure, reference is made again to  FIG. 2 . As depicted in  FIG. 3 , there can be four isolators on printing system  2000 ; first isolator set  2110  (second not shown on opposing side) and second isolator set  2112  (second not shown on opposing side), which support substrate floatation table  2200  of printing system  2000 . For gas enclosure assembly  1000  of  FIG. 2 , first isolator set  2110  and second isolator set  2112  can be mounted in each of a respective isolator well panel, such as first isolator wall panel  1325  and second isolator wall panel  1327  of middle base panel assembly  1320 . For gas enclosure assembly  1000  of  FIG. 2 , middle base assembly  1320  can include first printhead management system auxiliary enclosure  1330 , as well as second printhead management system auxiliary panel assembly  1370 .  FIG. 2  of gas enclosure assembly  1000  depicts first printhead management system auxiliary enclosure  1330  that can include first back wall panel assembly  1338 . Similarly, also depicted is second printhead management system auxiliary panel assembly  1370  that can include second back wall panel assembly  1378 . First back wall panel assembly  1338  of first printhead management system auxiliary enclosure  1330  can be constructed in a similar fashion as shown for second back wall panel assembly  1378 . Second back wall panel assembly  1378  of second printhead management system auxiliary panel assembly  1370  can be constructed from second back wall frame assembly  1378  having second seal-support panel  1375  sealably mounted to second back wall frame assembly  1378 . Second seal-support panel  1375  can have second passage  1365 , which is proximal to a second end of base  2100  (not shown). Second seal  1367  can be mounted on second seal-support panel  1375  around second passage  1365 . A first seal can be similarly positioned and mounted around a first passage for first printhead management system auxiliary enclosure  1330 . Each passage in auxiliary enclosure  1330  and auxiliary panel assembly  1370  can accommodate a printhead management system platform, such as first and second printhead management system platforms  2703  and  2704  of  FIG. 3  pass through the passages. 
     According to the present teachings, in order to sealably isolate auxiliary enclosure  1330  and auxiliary panel assembly  1370  the passages, such as second passage  1365  of  FIG. 2  must be sealable. It is contemplated that various seals, such as an inflatable seal, a bellows seal and a lip seal can be used for sealing a passage, such as second passage  1365  of  FIG. 2 , around a printhead management system platform affixed to a printing system base. 
     First printhead management system auxiliary enclosure  1330  and second printhead management system auxiliary panel assembly  1370  can include first printhead device assembly opening  1342  of first floor panel assembly  1341  and second printhead device assembly opening  1382  of second floor panel assembly  1381 ; respectively. First floor panel assembly  1341  is depicted in  FIG. 2  as part of first middle enclosure panel assembly  1340  of middle panel assembly  1300 . First floor panel assembly  1341  is a panel assembly in common with both first middle enclosure panel assembly  1340  and first printhead management system auxiliary enclosure  1330 . Second floor panel assembly  1381  is depicted in  FIG. 2  as part of second middle enclosure panel assembly  1380  of middle panel assembly  1300 . Second floor panel assembly  1381  is a panel assembly in common with both second middle enclosure panel assembly  1380  and second printhead management system auxiliary panel assembly  1370 . 
     As previously discussed herein, first printhead device assembly  2501  can be housed in first printhead device assembly enclosure  2503 , and second printhead device assembly  2502  can be housed in second printhead device assembly enclosure  2504 . According to systems and methods of the present teachings, first printhead device assembly enclosure  2503  and second printhead device assembly enclosure  2504  can have an opening at the bottom that can have a rim (not shown), so that various printhead devices; each printhead device having at least one printhead, can be positioned for printing during a printing process. Additionally, the portions of first printhead device assembly enclosure  2503  and second printhead device assembly enclosure  2504  forming a housing can be constructed as described herein for various panel assemblies, so that the frame assembly members and panels are capable of providing an hermetically-sealed enclosure. 
     A compressible gasket which can additionally be used for the hermetic sealing of various frame members, can be affixed around each of first printhead device assembly opening  1342  and second printhead device assembly opening  1382 , or alternatively around the rim of first printhead device assembly enclosure  2503  and second printhead device assembly enclosure  2504 . 
     According to the present teachings, compressible gasket material can be selected from, for example, but not limited by, any in the class of closed-cell polymeric materials, also referred to in the art as expanded rubber materials or expanded polymer materials. Briefly, a closed-cell polymer is prepared in a fashion whereby gas is enclosed in discrete cells; where each discrete cell is enclosed by the polymeric material. Properties of compressible closed-cell polymeric gasket materials that are desirable for use in gas-tight sealing of frame and panel components include, but are not limited by, that they are robust to chemical attack over a wide range of chemical species, possess excellent moisture-barrier properties, are resilient over a broad temperature range, and they are resistant to a permanent compression set. In general, compared to open-cell-structured polymeric materials, closed-cell polymeric materials have higher dimensional stability, lower moisture absorption coefficients, and higher strength. Various types of polymeric materials from which closed-cell polymeric materials can be made include, for example, but not limited by, silicone, neoprene, ethylene-propylene-diene terpolymer (EPT); polymers and composites made using ethylene-propylene-diene-monomer (EPDM), vinyl nitrile, styrene-butadiene rubber (SBR), and various copolymers and blends thereof. 
     In addition to close-cell compressible gasket materials, another example of a class of compressible gasket material having desired attributes for use in constructing embodiments of a gas enclosure assembly according to the present teachings includes the class of hollow-extruded compressible gasket materials. Hollow-extruded gasket materials as a class of materials have the desirable attributes, including, but not limited by, that they are robust to chemical attack over a wide range of chemical species, possess excellent moisture-barrier properties, are resilient over a broad temperature range, and they are resistant to a permanent compression set. Such hollow-extruded compressible gasket materials can come in a wide variety of form factors, such as for example, but not limited by, U-cell, D-cell, square-cell, rectangular-cell, as well as any of a variety of custom form factor hollow-extruded gasket materials. Various hollow-extruded gasket materials can be fabricated from polymeric materials that are used for closed-cell compressible gasket fabrication. For example, but not limited by, various embodiments of hollow-extruded gaskets can be fabricated from silicone, neoprene, ethylene-propylene-diene terpolymer (EPT); polymers and composites made using ethylene-propylene-diene-monomer (EPDM), vinyl nitrile, styrene-butadiene rubber (SBR), and various copolymers and blends thereof. Compression of such hollow cell gasket materials should not exceed about 50% deflection in order to maintain the desired attributes. It is contemplated that various types of inflatable seals can be utilized for sealing a printhead device assembly using first printhead device assembly docking gasket  1345  and second printhead device assembly docking gasket  1385 . Such inflatable seals may provide rapid sealing and unsealing during processing, as well as being fabricated from low-contamination materials, such as low particle generating, low outgassing polymeric materials, such as silicones, neoprenes and butyl rubber materials. 
     As depicted in  FIG. 2 , first printhead device assembly docking gasket  1345  and second printhead device assembly docking gasket  1385  can be affixed around first printhead device assembly opening  1342  and second printhead device assembly opening  1382 , respectively. During various printhead measurement and maintenance procedures, first printhead device assembly  2501  and second printhead device assembly  2502  can be positioned by first X,Z-axis carriage assembly  2301  and second X,Z-axis carriage assembly  2302 , respectively, over first printhead device assembly opening  1342  of first floor panel assembly  1341  and second printhead device assembly opening  1382  of second floor panel assembly  1381 , respectively. In that regard, for various printhead measurement and maintenance procedures, first printhead device assembly  2501  and second printhead device assembly  2502  can be positioned over first printhead device assembly opening  1342  of first floor panel assembly  1341  and second printhead device assembly opening  1382  of second floor panel assembly  1381 , respectively, without covering or sealing first printhead device assembly opening  1342  and second printhead device assembly opening  1382 . First X,Z-axis carriage assembly  2301  and second X,Z-axis carriage assembly  2302  can dock first printhead device assembly enclosure  2503  and second printhead device assembly enclosure  2504 , respectively, with first printhead management system auxiliary enclosure  1330  and second printhead management system auxiliary panel assembly  1370 , respectively. In various printhead measurement and maintenance procedures, such docking may effectively close first printhead device assembly opening  1342  and second printhead device assembly opening  1382  without the need for sealing first printhead device assembly opening  1342  and second printhead device assembly opening  1382 . For various printhead measurement and maintenance procedures, the docking can include the formation of a gasket seal between each of the printhead device assembly enclosures and the printhead management system panel assemblies. In conjunction with sealably closing passages, such as second passage  1365  and a complementary first passage of  FIG. 2 , when first printhead device assembly enclosure  2503  and second printhead device assembly enclosure  2504  are docked with first printhead management system auxiliary enclosure  1330  and second printhead management system auxiliary panel assembly  1370  to sealably close first printhead device assembly opening  1342  and second printhead device assembly opening  1382 , the combined structures so formed are hermetically sealed. 
     Additionally, according to the present teachings, an auxiliary enclosure can be isolated from, for example, another interior enclosure volume, such as the printing system enclosure, as well as the exterior of a gas enclosure assembly, by using a structural closure to sealably close a passageway, such as first printhead device assembly opening  1342  and second printhead device assembly opening  1382  of  FIG. 2 . According to the present teachings, a structural closure can include a variety of sealable coverings for an opening or passageway; such opening or passageway including non-limiting examples of an enclosure panel opening or passageway. According to systems and methods of the present teachings, a gate can be any structural closure that can be used to reversibly cover or reversibly sealably close any opening or passageway using pneumatic, hydraulic, electrical, or manual actuation. As such, first printhead device assembly opening  1342  and second printhead device assembly opening  1382  of  FIG. 2  can be reversibly covered or reversibly sealably closed using a gate. 
     In the expanded view of printing system  2000  of  FIG. 3 , various embodiments of a printing system can include substrate floatation table  2200 , supported by substrate floatation table base  2220 . Substrate floatation table base  2220  can be mounted on printing system base  2100 . Substrate floatation table  2200  of printing system can support substrate  2050 , as well as defining the travel over which substrate  2050  can be moved through gas enclosure assembly  1000  during the printing of a substrate. A Y-axis motion system of the present teachings can include first Y-axis support beam  2351  and second Y-axis support beam  2352 , which can include a gripper system (not shown) for holding a substrate, which will be discussed in more detail herein. Y-axis motion can be provided by either a linear air bearing or linear mechanical system. In that regard, in conjunction with a motion system; as depicted in  FIG. 3 , a Y-axis motion system, substrate floatation table  2200  can provide frictionless conveyance of substrate  2050  through a printing system. 
       FIG. 4  depicts an expanded view of first printhead management system  2701  housed within first printhead management system auxiliary enclosure  1330  in accordance with various embodiments of a gas enclosure assembly and system of the present teachings. As depicted in  FIG. 4 , auxiliary enclosure  1330  is shown as a cut-away view to more clearly see the details of first printhead management system  2701 . Various embodiments of a printhead management system according to the present teachings, such as first printhead management system  2701  of  FIG. 4 , apparatuses  2707 ,  2709 , and  2011  can be a variety of subsystems or modules for performing various functions. For example, apparatuses  2707 ,  2709 , and  2011  can be a drop measurement module, a printhead purge basin module and a blotter module. As depicted in  FIG. 4 , printhead replacement module  2713  can provide locations for docking at least one printhead device  2505 . In various embodiments of first printhead management system  2701 , first printhead management system auxiliary enclosure  1330  can be maintained to the same environmental specifications that gas enclosure assembly  1000  (see  FIG. 1 ) is maintained. First printhead management system auxiliary enclosure  1330  can have handler  2730  positioned for the carrying out tasks associated with various printhead management procedures. For example, each subsystem can have various parts that are consumable by nature, and require replacement, such as replacing blotter paper, ink, and waste reservoirs. Various consumable parts can be packaged for ready insertion, for example, in a fully automated mode using a handler. As a non-limiting example, blotter paper can be packaged in a cartridge format, which can be readily inserted for use into a blotting module. By way of another non-limiting example ink can be packaged in a replaceable reservoir, as well as a cartridge format for use in a printing system. Various embodiments of a waste reservoir can be packaged in a cartridge format, which can be readily inserted for use into a purge basin module. Additionally, parts of various components of a printing system subject to on-going use can require periodic replacement. During a printing process, expedient management of a printhead device assembly, for example, but not limited by, an exchange of a printhead device or printhead, can be desirable. A printhead replacement module can have parts, such as a printhead device or printhead, which can be readily inserted for use into a printhead device assembly. A drop measurement module used for checking for nozzle firing, as well as the measurement based on optical detection of drop volume, velocity and trajectory from every nozzle can have a source and a detector, which can require periodic replacement after use. Various consumable and high-usage parts can be packaged for ready insertion, for example, in a fully automated mode using a handler. Handler  2730  can have end effector  2736  mounted to arm  2534 . Various embodiments of an end effector configuration can be used, for example, a blade-type end effector, a clamp-type end effector, and a gripper-type end effector. Various embodiments of an end effector can include mechanical grasping and clamping, as well as pneumatic or vacuum-assisted assemblies to either actuate portions of the end effector or otherwise retain a printhead device or a printhead from a printhead device. 
     Regarding the replacement of a printhead device or printhead, printhead replacement module  2713  of printhead management system  2701   FIG. 4  can include a docking station for a printhead device having at least one printhead, as well as a storage receptacle for a printhead. As each printhead device assembly (see  FIG. 2 ) can include between about 1 to about 60 printhead devices, and as each printhead device can have between about 1 to about 30 printheads, then various embodiments of a printing system of the present teachings can have between about 1 to about 1800 printheads. In various embodiments of printhead replacement module  2713 , while a printhead device is docked, each printhead mounted to the printhead device can be maintained in an operable condition while not in use in a printing system. For example, when placed in a docking station, each printhead on each printhead device can be connected to an ink supply and an electrical connection. Electrical power can be provided to each printhead on each printhead device, so that a periodic firing pulse to each nozzle of each printhead can be applied while docked in order to ensure that the nozzles remain primed and do not clog. Handler  2730  of  FIG. 4  can be positioned proximal to printhead device assembly  2500 . Printhead device assembly  2500  can be docked over first printhead management system auxiliary enclosure  1330 , as depicted in  FIG. 4 . During a procedure for exchanging a printhead, handler  2730  can remove a target part; either a printhead or printhead device having at least one printhead, from printhead device assembly  2500 . Handler  2730  can retrieve a replacement part, such as a printhead device or a printhead, from printhead replacement module  2713 , and complete the replacement process. The removed part can be placed in printhead replacement module  2713  for retrieval. 
     As depicted in  FIG. 5A , gas enclosure  1000 A can house printing system  2000 A. As will be discussed in more detail subsequently herein, enclosed printing system  500 A can have features as described for various embodiments of enclosed printing system  500 C of  FIG. 11 , while printing system  2000 A can have all the features described for printing system  2000  of  FIG. 3 . Printing system  2000 A can have printing system base  2100 , which can be supported by at least two sets of isolators such as isolator set  2110  that includes isolators  2110 A and  2110 B of  FIG. 5A . Y-axis motion system  2350  can be mounted on printing system base  2100 . Substrate  2050  can be floatingly supported by substrate floatation table  2200 . Printing system base  2100  can support first riser  2120  and second riser  2122 , upon which bridge  2130  can be mounted. Printing system bridge  2130  can support first X-axis carriage assembly  2301 , upon which printhead device assembly  2500  can be mounted, and second X-axis carriage assembly  2302 , upon which camera assembly  2510  can be mounted. 
     Camera assembly  2510  of  FIG. 5A  can be utilized, for example, but not limited by, navigation, as well as inspection. Various embodiments of a printing system camera assembly can have different specifications regarding field of view and resolution. For example, one camera can be a line scan camera for in situ particle inspection, while a second camera can be used for the regular navigation of a substrate in a gas enclosure system, or for the location of a printhead device assembly relative to a substrate. Such a camera useful for regular navigation can be an area scan camera having a field of view in the range of about 5.4 mm×4 mm with a magnification of about 0.9× to about 10.6 mm×8 mm with a magnification of about 0.45×. In still other embodiments, one camera can be a line scan camera for in situ particle inspection, while a second camera can be used for the precise navigation of a substrate in a gas enclosure system, for example, for substrate alignment, or for the precise location of a printhead device assembly relative to a substrate. Such a camera can be useful for precise navigation can be an area scan camera having a field of view of about 0.7 mm×0.5 mm with a magnification of about 7.2×. 
     Additionally, gas enclosure  1000 A can have auxiliary enclosure  1330 , which can enclose printhead management system  2700 . Printhead management system  2700  can include a local waste assembly that can be in flow communication with a bulk waste assembly that can be housed within bulk ink delivery system  3500 . Auxiliary enclosure  1330  can be in flow communication with the remaining working volume of gas enclosure  1000 A through printhead device assembly opening  1342 . As previously discussed herein, printhead device assembly docking gasket  1345  can provide a gasket seal that can isolate auxiliary enclosure when printhead device assembly  2500  is sealably docked on printhead device assembly docking gasket  1345 . 
     As depicted in  FIG. 5A , various embodiments of bulk ink delivery system  3500  can be externally located to gas enclosure  1000 A and in flow communication with various embodiments of local ink delivery system  3700 , as indicated by the hatched input line of  FIG. 5A . Local ink delivery system  3700  can be mounted proximal printhead device assembly  2500  on first X-axis carriage assembly  2301 , and in flow communication with printhead device assembly  2500 . Additionally, a local waste assembly, which can be a component of printhead management system  2700 , can be in flow communication with a bulk waste assembly externally located to gas enclosure  1000 A, as indicated by the hatched output line of  FIG. 5A . As indicated in  FIG. 5B , local ink delivery system  3700  can be in flow communication with printhead device assembly  2500  through a local ink dispensing reservoir output line, which can be coupled to a printhead device assembly input line through compression fitting  3725 . As indicated in  FIG. 5C , printhead management system  2700  can have local waste reservoir assembly  2600 , which can be part of a purge basin module of printhead management system  2700 , as previously discussed herein. Local waste reservoir assembly  2600  can include waste liquid inlet receptacle  2610 , depicted in  FIG. 5C  being funnel-shaped. Waste liquid inlet receptacle  2610  can be any receptacle capable of collecting liquid from a printhead device assembly waste line, while preventing liquid loss thereby. Local waste reservoir assembly  2600  can include local waste reservoir  2620 , which can have first liquid level indicator  2622 A, for monitoring a high waste liquid level, and second liquid level indicator  2622 B, for monitoring a low waste liquid level. Local waste reservoir  2620  can have vent  2624 , and as previously discussed herein, local waste reservoir  2620  can be in flow communication with a bulk waste assembly housed in bulk ink delivery system  3500 . 
     Enclosed printing system  500 B of  FIG. 5D  can have the many of the features as described herein for enclosed printing system  500 A of  FIG. 5A . As depicted in  FIG. 5D , gas enclosure  1000 B can house printing system  2000 B. As will be discussed in more detail subsequently herein, enclosed printing system  500 B of  FIG. 5D  can have features as described for various embodiments of enclosed printing system  500 C of  FIG. 11 , while printing system  2000 B can have all the features described for printing system  2000  of  FIG. 3 , as well as printing system  2000 A of  FIG. 5A . Printing system  2000 B of  FIG. 5D  can have printing system base  2100 , which can be supported by at least two sets of isolators such as isolator set  2110  that includes isolators  2110 A and  2110 B. Y-axis motion system  2350  can be mounted on printing system base  2100 . Substrate  2050  can be floatingly supported by substrate floatation table  2200 . Printing system base  2100  can support first riser  2120  and second riser  2122 , upon which bridge  2130  can be mounted. Printing system bridge  2130  can support first X-axis carriage assembly  2301 , upon which printhead device assembly  2500  can be mounted, and second X-axis carriage assembly  2302 , upon which camera assembly  2510  can be mounted. Recalling, various embodiments of enclosed printing system  500 A of  FIG. 5A  can include a contoured enclosure, such as depicted with gas enclosure  1000  of  FIG. 1 , which can have auxiliary enclosure  1330 . Various embodiments of gas enclosure  1000 B of  FIG. 5D  can be a contoured enclosure according to various embodiments of a gas enclosure without an auxiliary enclosure, as will be described in more detail herein for  FIG. 10A . 
     As depicted in  FIG. 5D , various embodiments of bulk ink delivery system  3500  can be externally located to gas enclosure  1000 B and in flow communication with various embodiments of local ink delivery system  3700 , as indicated by the hatched input line of  FIG. 5D . Local ink delivery system  3700  can be mounted proximal printhead device assembly  2500  on first X-axis carriage assembly  2301 , and in flow communication with printhead device assembly  2500 . Additionally, a local waste assembly, which can be a component of printhead management system  2700 , can be in flow communication with a bulk waste assembly externally located to gas enclosure  1000 B, as indicated by the hatched output line of  FIG. 5D . 
       FIG. 6A  and  FIG. 6B  are schematic views of a printing system ink delivery system that can be housed in gas enclosure  1000 A and  1000 B, respectively. Various embodiments of gas enclosure  1000 A can be a contoured enclosure, such as depicted with gas enclosure  1000  of  FIG. 1 , which can have auxiliary enclosure  1330 . Various embodiments of gas enclosure  1000 B of  FIG. 6B  can be a contoured enclosure according to various embodiments of a gas enclosure without an auxiliary enclosure, as will be described in more detail herein for  FIG. 10A . The printing system ink delivery system for  FIG. 6A  and  FIG. 6B  can include local ink delivery system  3700 , which in in flow communication with bulk ink delivery system  3500 , as indicated by the as indicated by the hatched input line of  FIG. 6A  and  FIG. 6B . Local ink delivery system  3700  can be in flow communication with printhead device assembly  2500 , thereby providing a supply of ink to one or more printhead device, each printhead device including one or more printhead device assembly. Various embodiments local ink delivery system  3700  of the present teachings can include local ink replenishment reservoir  3710 , local ink dispensing reservoir  3720 , and pneumatic control manifold  3730 . 
     Local ink replenishment reservoir  3710 , which can include local ink replenishment reservoir vent  3712 , can receive a supply of ink from bulk ink delivery system  3500  from a bulk ink delivery system inlet line, as indicated by the hatched input line. Local ink delivery system  3700  can include at least three liquid level indicators associated with local ink replenishment reservoir  3710 ; an upper-level liquid indicator  3716 A, mid-level liquid indicator  3716 B, and lower-level liquid indicator  3716 C. The liquid level indicators  3716 A,  3716 AB and  3716 AC for local ink replenishment reservoir  3710  can be part of a dynamic liquid level control system that can ensure that a sufficient level of an ink is supplied from bulk ink delivery system  3500  to local ink replenishment reservoir  3710 . As depicted in  FIG. 6A  and  FIG. 6B , for various embodiment of a printing system, a sufficient amount of ink in local ink replenishment reservoir  3710  can be defined by liquid level indicator  3716 A, so that an ink level will not exceed liquid level indicator  3716 A within the tolerance of the liquid level control system to maintain that level. As depicted in  FIG. 6A  and  FIG. 6B , for various embodiment of a printing system, a sufficient amount of ink in local ink replenishment reservoir  3710  can be defined by liquid level indicator  3716 B, so that an ink level will be essentially at the level of liquid level indicator  3716 B within the tolerance of the liquid level control system to maintain that level. As depicted in  FIG. 6A  and  FIG. 6B , for various embodiment of a printing system, a sufficient amount of ink in local ink replenishment reservoir  3710  can be defined by liquid level indicator  3716 C, so that an ink level will not go below liquid level indicator  3716 C within the tolerance of the liquid level control system to maintain that level. According to the present teachings, various embodiments of upper-level liquid indicator  3716 A, mid-level liquid indicator  3716 B, and lower-level liquid indicator  3716 C can control the level of an ink at their respective positions on local ink replenishment reservoir  3710  to a tolerance of +/−200 microns. According to the present teachings, various embodiments of upper-level liquid indicator  3716 A, mid-level liquid indicator  3716 B, and lower-level liquid indicator  3716 C can control the level of an ink at their respective positions on local ink replenishment reservoir  3710  to a tolerance of +/−500 microns. Local ink replenishment reservoir  3710  can be in flow communication with local ink replenishment reservoir outlet line  3714 , which can be in flow communication with local ink dispensing reservoir  3720  via local ink dispensing reservoir inlet line  3722 . As depicted in  FIG. 6A  and  FIG. 6B , flow communication between local ink replenishment reservoir outlet line  3714  and local ink dispensing reservoir inlet line  3722  can be controlled using local ink delivery system control valve  3715 . 
     Local ink delivery system  3700  can include at least four liquid level indicators associated with local ink dispensing reservoir  3720 ; upper-level liquid indicator  3726 A, first mid-level liquid indicator  3726 B, second mid-level liquid indicator  3726 C, and lower-level liquid indicator  3726 D. As previously discussed herein for local ink replenishment reservoir  3710 , the liquid level indicators associated with local ink dispensing reservoir  3720  can be part of a dynamic liquid level control system that can ensure that a sufficient level of an ink is supplied from local ink replenishment reservoir  3710  to local ink dispensing reservoir  3720 . In the case of the liquid level in local ink dispensing reservoir  3720 , in order for the static head pressure to be constant above a printhead device assembly, the liquid level in local ink dispensing reservoir  3720  can be keep constant within a desired tolerance using first mid-level liquid indicator  3726 B and second mid-level liquid indicator  3726 C. Additionally, as depicted in  FIG. 6A  and  FIG. 6B , for various embodiment of a printing system, a sufficient amount of ink in local ink dispensing reservoir  3720  can be defined by liquid level indicator  3726 A, so that an ink level will not exceed liquid level indicator  3726 A within the tolerance of the liquid level control system to maintain that level. Similarly, as depicted in  FIG. 6A  and  FIG. 6B , for various embodiment of a printing system, a sufficient amount of ink in local ink dispensing reservoir  3720  can be defined by liquid level indicator  3726 D, so that an ink level will not go below liquid level indicator  3726 D within the tolerance of the liquid level control system to maintain that level. According to the present teachings, various embodiments of upper-level liquid indicator  3726 A, first mid-level liquid indicator  3726 B, second mid-level liquid indicator  3726 C, and lower-level liquid indicator  3726 D can control the level of an ink at their respective positions on local ink dispensing reservoir  3720  to a tolerance of +/−200 microns. According to the present teachings, various embodiments of upper-level liquid indicator  3726 A, first mid-level liquid indicator  3726 B, second mid-level liquid indicator  3726 C, and lower-level liquid indicator  3726 D can control the level of an ink at their respective positions on local ink dispensing reservoir  3720  to a tolerance of +/−500 microns. Pneumatic control assembly  3730  can provide control between local ink dispensing reservoir  3720  and various pneumatic control sources, such as gas  3732 , such as nitrogen, regulated 3434 vacuum source and vent  3436 . 
     Local ink dispensing reservoir outlet line  3724  can be in flow communication with printhead device assembly inlet line  2502 ; thereby providing flow communication between local ink dispensing reservoir  3720  and printhead device assembly  2500 . Local ink dispensing reservoir outlet line  3724  can be coupled to printhead device assembly inlet line  2502  using compression fitting  3725 . As depicted in  FIG. 6A  and  FIG. 6B , local ink dispensing reservoir  3720  can be in flow communication with printhead device assembly inlet line  2502 . Printhead device assembly inlet line  2502  can be in flow communication with a plurality of printheads devices; printhead device  2505 A, printhead device  2505 B, and printhead device  2505 C, through printhead device assembly supply manifold  2510 . Each printhead device can have a plurality of printheads per device. As depicted schematically in  FIG. 6A  and  FIG. 6B , printhead device  2505 A has printheads  2507 A,  2507 B and  2507 C, while printhead device  2505 B has printheads  2507 D,  2507 E and  2507 F, and printhead device  2505 C has printheads  2507 G,  2507 H and  2507 I. Printhead device assembly supply manifold  2510  can have supply manifold inlet line  2512 A, supply manifold inlet line  2512 B, and supply manifold inlet line  2512 C, in flow communication with printhead device  2505 A, printhead device  2505 B, and printhead device  2505 C, respectively. Flow communication between printhead device assembly inlet line  2502  and supply manifold inlet line  2512 A, supply manifold inlet line  2512 B, and supply manifold inlet line  2512 C can be controlled by supply manifold inlet control valve  2513 A, supply manifold inlet control valve  2513 B, and supply manifold inlet control valve  2513 C, respectively. Flow spitting into three equal flow paths can be done for each of supply manifold inlet line  2512 A, supply manifold inlet line  2512 B, and supply manifold inlet line  2512 C, as schematically depicted in  FIG. 6A  and  FIG. 6B , so that each of three printheads for each printhead device receives equal flow of ink. 
     Printhead device  2505 A, printhead device  2505 B, and printhead device  2505 C, can be in flow communication with printhead device assembly return manifold  2520 . Printhead device assembly return manifold  2520  can be in flow communication with return manifold outlet line  2522 A, return manifold outlet line  2522 B, and return manifold outlet line  2522 C. Return manifold outlet line  2522 A, return manifold outlet line  2522 B, and return manifold outlet line  2522 C can be in flow communication with printhead device assembly outlet line  2506 . Flow communication between printhead device assembly return manifold  2520  and printhead device assembly outlet line  2506  can be controlled by return manifold outlet control valve  2523 A, return manifold outlet control valve  2523 B, and return manifold outlet control valve  2523 C, which are associated with return manifold outlet line  2522 A, return manifold outlet line  2522 B, and return manifold outlet line  2522 C respectively. Both printhead device assembly inlet line  2502  and printhead device assembly outlet line  2506  can be in flow communication with printhead device assembly output waste line  2530 . Flow communication between printhead device assembly inlet line  2502  and printhead device assembly output waste line  2530  can be controlled using printhead device assembly waste line first control valve  2531 . Printhead device assembly waste line second control valve  2532  can control the flow communication between printhead device assembly  2500  and a local waste assembly. Printhead device assembly output waste line  2530  can be in flow communication with local ink waste assembly  2600  (see for example  FIG. 5A ), which is part of printhead management system  2700  that can be housed within auxiliary enclosure  1330  of  FIG. 6A  or gas enclosure  1000 B of  FIG. 6B . 
     With respect to  FIG. 6A , as previously discussed herein, auxiliary enclosure  1330  can be in flow communication with the remaining working volume of gas enclosure  1000 A through printhead device assembly opening  1342 . Further, printhead device assembly docking gasket  1345  can provide a gasket seal that can isolate auxiliary enclosure when printhead device assembly  2500  is sealably docked on printhead device assembly docking gasket  1345 . Local ink waste assembly  2600  in turn is in flow communication with a bulk ink delivery system waste assembly, as indicated by the hatched output line of  FIG. 6A . A bulk ink delivery system waste assembly can be housed within bulk ink delivery system  3500 . 
     In  FIG. 7 , a schematic depiction of various embodiments of bulk ink delivery system  3500  is shown. As indicated in  FIG. 7 , bulk ink delivery system  3500  can be in flow communication with various embodiments of local ink delivery system  3700  according to the present teachings. For various embodiments of bulk ink delivery system  3500 , pump P B1  can be a metering pump that can effectively pump both liquid and gaseous fluids. In that regard, both bulk ink supply system  3510  and maintenance system  3514  of bulk ink delivery system  3500  can utilize metering pump P B1  for flow control. As depicted in  FIG. 7 , metering pump P B1  provides a controllable manifold system that has three input lines, with the potential for three output lines; of which two are indicated in  FIG. 7 , all of which are controlled using metering pump valves as indicated. The number of controllable input and output lines can vary, according to various embodiments of metering pumps. Various embodiments of metering pumps utilized in embodiments of bulk ink delivery systems of the present teachings can have attributes that can include, for example, but not limited by, capable of controlling both liquid and gaseous fluids, corrosion resistant polymeric surfaces in contact with fluid flow to prevent corrosion and contamination, zero dead volume connections preventing cross-contamination, minimum hold-up volume for fast priming using a minimum volume of various inks, and valves with suckback capability. 
     Bulk ink delivery system (BIDS)  3500  of  FIG. 7  can have bulk ink supply system  3510  that can have first BIDS ink supply line L B1  in flow communication with a first ink source, and second BIDS ink supply line L B2  in flow communication with a second ink source. First BIDS ink supply line L B1  and second BIDS ink supply line L B2  can controlled by first BIDS valve V B1  and second BIDS valve V B2 , respectively, which can part of the assembly of multi-port metering pump P B1 , as indicated in  FIG. 7 . In addition to providing flow control for bulk ink supply system  3510 , given the capability that metering pump P B1  has for controllably handling a variety of different fluids with minimum hold-up volume, metering pump P B1  can also be used for controllably handling maintenance system  3514 . For example, in  FIG. 7 , third BIDS solvent supply line L B3  can be in flow communication with a solvent source and forth BIDS gas supply line L B4  can be in flow communication with an inert gas source, for example, a nitrogen source as indicated in  FIG. 7 . Third BIDS solvent supply line L B3  and forth BIDS gas supply line L B4  can be controlled by third BIDS solvent supply valve V B3  and forth BIDS gas supply valve V B4 , respectively. As depicted in  FIG. 7 , third BIDS solvent supply line L B3  and forth BIDS gas supply line L B4  can be in flow communication with fifth BIDS line L B5 , which can be controlled by fifth BIDS maintenance system supply valve V B5 . Fifth BIDS maintenance system supply valve V B5  can part of the assembly of multi-port metering pump P B1 , as indicated in  FIG. 7 . Third BIDS solvent supply line L B3 , and forth BIDS gas supply line L B4  can be joined at a T-junction using two valves, as shown in  FIG. 7 , or a 3-way valve can be used. Third BIDS solvent supply valve V B3  and forth BIDS inert gas supply valve V B4  are in a normally closed position during processing, but can be selectively opened during a maintenance procedure, as will be discussed in more detail subsequently, herein. 
     Initially for various embodiments of systems and methods of  FIG. 7 , for example, before a printing procedure has begun, priming of ink line through the manifold system of metering pump P B1  can be done. For example, once an ink supply is available from first ink supply container Ink  1 , first BIDS ink supply line L B1  can be primed with ink from Ink  1  by opening first BIDS ink supply valve V B1  and BIDS waste line valve V BW , while all other valves remain closed. With the valve states so positioned, priming of first BIDS ink supply line L B1  can be done, in which there is flow communication between first BIDS ink supply line L B1  and bulk ink delivery system waste assembly  3516  through BIDS waste line L BW . After priming, during, for example, the initiation of a printing process, first BIDS ink supply valve V B1  and sixth BIDS valve V B6  of metering pump P B1  can be open, while all other valves are closed. With the valve states so positioned, first ink supply container, Ink  1 , is in flow communication with bulk ink delivery system  3500 , which is in flow communication with local ink delivery system  3700 . Second BIDS line L B2  can be primed with ink from Ink  2  in a similar fashion as given in the example for priming first BIDS ink supply line L B1 . 
     Though two ink supply sources are indicated in  FIG. 7 , a plurality of ink supply containers can be included in bulk ink supply system  3510 , and can act as sequential supply sources of ink. For example, as shown in  FIG. 7 , when the level of ink in first ink supply container, Ink  1 , is at the low level indicator, first BIDS ink supply valve V B1  of metering pump P B1  can be closed, so that first ink supply container, Ink  1 , can be isolated and either refilled or replaced. Following the isolation of Ink  1 , second BIDS ink supply valve V B2  of metering pump P B1  can be opened, so that second ink supply container, Ink  2 , can act as the source of ink supply for a gas enclosure system, such as enclosed printing system  500 A of  FIG. 13 . Either one of first BIDS line ink supply L B1  or second BIDS ink supply line L B2  can be in flow communication with sixth BIDS line L B6 , depending on which ink supply source is in use. During processes requiring ink flow from bulk ink supply system  3510 , first BIDS ink supply valve V B1  and sixth BIDS valve V B6  of metering pump P B1  can be open, while all other valves are closed, allowing flow between first BIDS ink supply line L B1  and sixth BIDS line L B6 . Sixth BIDS line L B6  passes through filter  3512  and is in flow communication with seventh BIDS line L B7 , which is in flow communication with a degasser for removing, for example, but not limited by, dissolved gases in an ink from a bulk ink supply source of bulk ink supply system  3510 . Finally, after being degassed, ink can flow through eighth BIDS line L BB , which is in flow communication with local ink delivery system  3700 . 
     As previously discussed herein, in addition to bulk ink supply system  3510 , bulk ink delivery system  3500  of  FIG. 7  can have BIDS maintenance system  3514 . BIDS maintenance system  3514  can include third BIDS solvent supply line L B3  and forth BIDS gas supply line L B4 , which can be controlled by third BIDS solvent supply valve V B3  and forth BIDS inert gas supply valve V B4 , respectively. As depicted in  FIG. 7 , third BIDS solvent supply line L B3  and forth BIDS gas supply line L B4  can be in flow communication with fifth BIDS line L B5 . Fifth BIDS line L B5  can be controlled by fifth BIDS maintenance system supply valve V B5  of metering pump P B1 . Additionally, for bulk ink delivery system  3500  of  FIG. 7 , BIDS waste line L BW  can be in flow communication with bulk ink delivery system waste assembly  3516 . BIDS waste line L BW  can be controlled by BIDS waste line valve V BW  of metering pump P B1 . Third BIDS solvent supply valve V B3 , forth BIDS gas supply valve V B4 , fifth BIDS maintenance system supply valve V B5 , and BIDS waste line valve V BW  are in a normally closed position during processing, but can be selectively opened during a maintenance procedure. 
     For example, during a maintenance procedure, the BIDS valves of metering pump P B1  associated with bulk ink supply system  3510 , BIDS valves V B1 , V B2 , and V B6 , would remain in a closed position. If a maintenance procedure utilizing a solvent purge is implemented, then BIDS valves V B3 , V B5 , and V BW  can be opened, so that solvent priming can be done through fifth BIDS line L B5 , which can be in flow communication bulk ink delivery system waste assembly  3516 . After priming, during a maintenance procedure utilizing solvent cleaning of, for example, lines within local ink delivery system  3700 , then BIDS waste line valve V BW  can be closed, and BIDS valves V B3 , V B5 , and V B6  can be opened, so that solvent can flow through fifth BIDS line L B5 , which can be in flow communication with sixth BIDS line L B6 . Sixth BIDS line L B6  is in flow communication with local ink delivery system  3700 , as described herein, providing solvent flow throughout local ink delivery system  3700 , and eventually to bulk ink delivery system waste assembly  3516  through ninth BIDS line L B9 . Additionally, if a maintenance procedure utilizing an inert gas is implemented, then BIDS valves V B4 , V B5 , and V B6  can be opened, so that inert gas can flow through fifth BIDS line L B5 , which can be in flow communication with sixth BIDS line L B6 . Sixth BIDS line L B6  is in flow communication with local ink delivery system  3700 , as described herein. 
       FIG. 8A  is a bottom perspective view of printhead device assembly  2500 , mounted on a printhead device assembly positioning system, such as first X-axis carriage assembly  2301  (see also  FIG. 3 ). First X-axis carriage assembly  2301  can be positioned in an X-axis direction on printing system bridge  2130  relative to a substrate, such as substrate  2050  of  FIG. 3 . As shown in  FIG. 8A , service bundle housing  2410  is mounted to printing system bridge  2130 . Service bundle housing  2410  can contain various service bundles operatively connected from various apparatuses and system to a gas enclosure system including a printing system. Various embodiments of a service bundle can include bundled optical cables, electrical cables, wires and tubing, and the like, for providing optical, electrical, mechanical, and fluidic functions for various assemblies and systems disposed within the interior of the gas enclosure system. As will be discussed in more detail subsequently herein in regard to  FIG. 10A  and  FIG. 10B , flow communication between a bulk ink delivery system and a local ink delivery system of can occur by a fluid line running through a service bundle housing to local ink delivery system. During various process steps, such as printing and maintenance steps, as X-axis carriage assembly  2301  moves printhead device assembly  2500  across printing system bridge  2130 , various service bundles move accordingly. Therefore, liquid ink lines in such service bundles are subject to continuous flexure and wear. According to systems and methods of the present teachings, a bulk ink delivery system external a gas enclosure system can be in fluid communication with a local ink delivery system internal to a gas enclosure system utilizing a double conduit system, in which an ink line is run through a conduit, which can be in flow communication with a bulk waste assembly. In that regard, should an ink line develop a leak, the liquid can run through the outer conduit to waste. 
     As depicted in  FIG. 8A  printhead device assembly  2500  can have printhead devices  2505 A,  2505 B, and  2505 C, which can be substantially housed within a printhead device assembly enclosure (not shown) and mounted to printhead device assembly mounting plate  2515 . Printhead devices  2505 A,  2505 B, and  2505 C can be mounted to printhead device assembly mounting plate  2515 , so that each printhead device can extend through printhead device assembly mounting plate  2515  to be positioned relative to a substrate, such as substrate  2050  of  FIG. 3 . For various embodiments of printing system  2000  of  FIG. 3  or printing system  2000 A of  FIG. 5A , a printhead device assembly can include between about 1 to about 60 printhead devices, where each printhead device can have between about 1 to about 30 printheads in each printhead device. As depicted in  FIG. 8A , according to systems and methods of the present teachings, printhead device assembly  2500  can have three printhead devices, where each printhead device as depicted in  FIG. 6A  and  FIG. 6B  can three printheads;  2507 A through  2507 I. As depicted in  FIG. 8A , printhead device assembly  2500  can be in flow communication with local ink delivery system  3700 , as additionally depicted in  FIG. 6A  and  FIG. 6B . As depicted in  FIG. 8A , local ink delivery system  3700  can have local ink replenishment reservoir  3710 , which can be in flow communication with local ink dispensing reservoir  3720 . Local ink delivery system drip pan  3740  can be configured to provide collection of liquid, such as ink or solvent used to clean ink lines, thereby protecting the printing system situated below local ink delivery system  3700  from fluid leakage. As previously discussed herein for  FIG. 6A  and  FIG. 6B , local ink dispensing reservoir  3720  can be in flow communication with each printhead device,  2505 A,  2505 B, and  2505 C; each printhead device of which is depicted having three printheads. According to systems and methods of the present teachings, printhead device assembly  2500  can accommodate any of an end-user selected printheads. As previously discussed in herein, given the number of printhead devices and printheads requiring continual maintenance, printhead device assembly  2500  can be positioned over a maintenance system in an auxiliary enclosure, as depicted in  FIG. 2  through  FIG. 4 , for ready placement or replacement of a printhead device or a printhead. 
     As illustrated generally in the expanded bottom perspective view of  FIG. 8B , printhead device assembly  2500  can have printhead devices  2505 A,  2505 B, and  2505 C. As previously mentioned herein, printhead devices  2505 A,  2505 B, and  2505 C can be substantially housed within printhead device assembly enclosure (not shown) and mounted to printhead device assembly mounting plate  2515 , so that the printhead devices can extend through printhead device assembly mounting plate  2515  to be positioned relative to a substrate, such as substrate  2050  of  FIG. 3 . As depicted schematically in  FIG. 6A  and  FIG. 6B , and illustrated generally in  FIG. 8B , each printhead device can have a supply manifold inlet line, as well as a return manifold outlet line. Printhead device assembly supply manifold  2510  of  FIG. 6A  can have supply manifold inlet line  2512 A, supply manifold inlet line  2512 B, and supply manifold inlet line  2512 C, in flow communication with printhead device  2505 A, printhead device  2505 B, and printhead device  2505 C, respectively, as depicted schematically in  FIG. 6A  and  FIG. 6B  and illustrated generally in  FIG. 8B . Similarly, on the outlet side, printhead device  2505 A, printhead device  2505 B, and printhead device  2505 C, can be in flow communication with printhead device assembly return manifold  2520 , as depicted schematically in  FIG. 6A  and  FIG. 6B . Printhead device assembly return manifold  2520  of  FIG. 6A  can be in flow communication with return manifold outlet line  2522 A, return manifold outlet line  2522 B, and return manifold outlet line  2522 C, as depicted schematically in  FIG. 6A  and  FIG. 6B , and illustrated generally in  FIG. 8B . Return manifold outlet line  2522 A, return manifold outlet line  2522 B, and return manifold outlet line  2522 C can be in flow communication with printhead device assembly outlet line  2506 , as depicted schematically in  FIG. 6A  and  FIG. 6B . Additionally, as illustrated generally in  FIG. 8B , local ink delivery system  3700  can be mounted proximal to printhead device assembly  2500 . Local ink delivery system  3700  can include local ink replenishment reservoir  3710  and local ink dispensing reservoir  3720 , as well as local ink delivery system drip pan  3740 . 
     According to various systems and methods of the present teaching a printhead device, such as printhead devices  2505 A,  2505 B, and  2505 C of  FIG. 8A  and  FIG. 8B  can be manually or automatically inserted from the bottom of printhead device assembly  2500 . For example, as depicted in  FIG. 4  printhead installation or replacement can be done robotically. As previously discussed herein in reference to  FIG. 2  through  FIG. 4 , a gas enclosure, such as gas enclosure  1000 A, can have auxiliary enclosure  1330 , which can enclose printhead management system  2701 . In  FIG. 4 , the installation or replacement of a printhead device or printhead, can be done in auxiliary enclosure  1330  using robot  2530 . Printhead replacement module  2713  of printhead management system  2701   FIG. 4  can include a docking station for a printhead device having at least one printhead, as well as a storage receptacle for a plurality of printhead devices, as well as a plurality of printheads. Each printhead device assembly of the present teachings can include between about 1 to about 60 printhead devices, and as each printhead device can have between about 1 to about 30 printheads. Accordingly, in addition to having between 1 to about 60 printhead devices, various embodiments of a printing system of the present teachings can have between about 1 to about 1800 printheads; all of which require occasional maintenance. 
     Printhead device  2505 , as illustrated generally in  FIG. 9 , can include a plurality of printheads, such as printheads  2507 A,  2507 B, and  2507 C. As previously mentioned, printhead device  2505  can accommodate any of an end-user selected printhead; each printhead device having at least one printhead. As illustrated in  FIG. 9 , printheads  2507 A,  2507 B, and  2507 C can have printhead nozzle plates  2509 A,  2509 B, and  2509 C, respectively. Printhead device  2505  can have printhead device electrical bulk head  2550 , which can provide electrical service to each printhead. Additionally, printhead device  2505  can have supply manifold inlet line  2512  and return manifold outlet line  2522 , which provide flow communication to an ink supply and a local waste reservoir assembly, respectively. 
       FIG. 10A  illustrates generally a perspective view of enclosed printing system  500 B, which can have all of the features as described herein for enclosed printing system  500 B of  FIG. 5D . Gas enclosure  1000 B of  FIG. 10A  can include first tunnel enclosure section  1200 B, bridge enclosure section  1300 B, and second tunnel enclosure section  1400 B. A printing system, such as printing system  2000 B of  FIG. 5D , can be housed within gas enclosure  1000 B. In the perspective view of  FIG. 10A , printing system base  2100  is shown, as well as bridge  2130 . Upon bridge  2130 , carriage assembly  2301 , for which various embodiments have been described herein, is mounted. As depicted in  FIG. 10A , local ink delivery system is mounted to carriage assembly  2301  proximal to a printhead device assembly. Bulk ink delivery system  3500  is shown positioned exterior enclosed printing system  500 B. Extending from bulk ink delivery system  3500  is ink delivery line  3520 , which provides flow communication between bulk ink delivery system  3500  and local ink delivery system  3700 , such as described herein for L B8  of  FIG. 7 . Ink delivery line  3520  is depicted as routed through second tunnel enclosure section  1400 B of gas enclosure  1000 B, and through a service bundle housing (not shown; see for example, service bundle housing  2410  of  FIG. 8A ). 
     As depicted in  FIG. 10A , and shown in the expanded view of  FIG. 10B , the routing of ink delivery line  3520  continues from the service bundle housing and around the exterior carriage assembly  2301  to local ink replenishment reservoir  3710  of local ink delivery system  3700 . Local ink replenishment reservoir  3710  is in flow communication with local ink dispensing reservoir  3720 , as described herein, for example, but not limited by, for  FIG. 6A  and  FIG. 6B . As depicted in  FIG. 10B , local ink delivery system  3700  is mounted on carriage assembly  2301  proximal to printhead device assembly  2500 . As described herein, for example, but not limited by, for  FIG. 5A  through  FIG. 6B , as well as  FIG. 8A  and  FIG. 8B , local ink delivery system  3700  is in flow communication with printhead device assembly  2500 . According to the present teachings, local ink delivery system  3700 , shown proximal to a printhead device assembly  2500 , can have a two-stage ink supply. As depicted in  FIG. 10A , local ink replenishment reservoir  3710  is proximal to local ink dispensing reservoir  3720 . 
     As previously discussed herein with respect to  FIG. 6A  and  FIG. 6B , local ink delivery system  3700  is configured with liquid level indicators that can be part of a dynamic liquid level control system that can ensure that a sufficient level of an ink is supplied from bulk ink delivery system  3500  to local ink replenishment reservoir  3710 . Additionally, local ink replenishment reservoir  3710  is configured to supply ink to local ink dispensing reservoir  3720  to a constant level. According to the present teachings, a local ink dispensing reservoir can be in flow communication with a plurality of printhead devices. As such, a two-stage local ink delivery system maintaining a constant level in a local ink dispensing reservoir can provide constant head pressure to the plurality of printhead devices. 
       FIG. 11  is a schematic diagram showing enclosed printing system  500 C utilizing gas enclosure assembly  1005 . Various embodiments of enclosed printing system  500 C according to the present teachings can comprise gas enclosure assembly  1000 B for housing a printing system, gas purification loop  3130  in fluid communication gas enclosure assembly  1000 B, and at least one thermal regulation system  3140 . Additionally, various embodiments of enclosed printing system  500 C can have pressurized inert gas recirculation system  3000 , which can supply inert gas for operating various devices, such as a substrate floatation table for a printing system. Various embodiments of a pressurized inert gas recirculation system  3000  can utilize a compressor, a blower and combinations of the two as sources for various embodiments of pressurized inert gas recirculation system  3000 , as will be discussed in more detail subsequently herein. Additionally, enclosed printing system  500 C can have a circulation and filtration system internal to enclosed printing system  500 C (not shown). 
     As depicted in  FIG. 11 , for various embodiments of a gas enclosure assembly according to the present teachings, the design of a filtration system can separate the inert gas circulated through gas purification loop  3130  from the inert gas that is continuously filtered and circulated internally for various embodiments of a gas enclosure assembly. Gas purification loop  3130  includes outlet line  3131  from gas enclosure assembly  1000 B, to a solvent removal component  3132  and then to gas purification system  3134 . Inert gas purified of solvent and other reactive gas species, such as oxygen, ozone and water vapor, are then returned to gas enclosure assembly  1000 B through inlet line  3133 . Gas purification loop  3130  may also include appropriate conduits and connections, and sensors, for example, oxygen, ozone, water vapor and solvent vapor sensors. A gas circulating unit, such as a fan, blower or motor and the like, can be separately provided or integrated, for example, in gas purification system  3134 , to circulate gas through gas purification loop  3130 . According to various embodiments of a gas enclosure assembly, though solvent removal system  3132  and gas purification system  3134  are shown as separate units in the schematic shown in  FIG. 11 , solvent removal system  3132  and gas purification system  3134  can be housed together as a single purification unit. 
     Gas purification loop  3130  of  FIG. 11  can have solvent removal system  3132  placed upstream of gas purification system  3134 , so that inert gas circulated from gas enclosure assembly  1000 B passes through solvent removal system  3132  via outlet line  3131 . According to various embodiments, solvent removal system  3132  may be a solvent trapping system based on adsorbing solvent vapor from an inert gas passing through solvent removal system  3132  of  FIG. 11 . A bed or beds of a sorbent, for example, but not limited by, such as activated charcoal, molecular sieves, and the like, may effectively remove a wide variety of organic solvent vapors. For various embodiments of a gas enclosure system cold trap technology may be employed to remove solvent vapors in solvent removal system  3132 . As previously discussed herein, for various embodiments of a gas enclosure system according to the present teachings, sensors, such as oxygen, ozone, water vapor and solvent vapor sensors, may be used to monitor the effective removal of such species from inert gas continuously circulating through a gas enclosure system, such as enclosed printing system  500 C of  FIG. 11 . Various embodiments of a solvent removal system can indicate when sorbent, such as activated carbon, molecular sieves, and the like, has reached capacity, so that the bed or beds of sorbent can be regenerated or replaced. Regeneration of a molecular sieve can involve heating the molecular sieve, contacting the molecular sieve with a forming gas, a combination thereof, and the like. Molecular sieves configured to trap various species, including oxygen, ozone, water vapor, and solvents, can be regenerated by heating and exposure to a forming gas that comprises hydrogen, for example, a forming gas comprising about 96% nitrogen and 4% hydrogen, with said percentages being by volume or by weight. Physical regeneration of activated charcoal can be done using a similar procedure of heating under an inert environment. 
     Any suitable gas purification system can be used for gas purification system  3134  of gas purification loop  3130  of  FIG. 11 . Gas purification systems available, for example, from MBRAUN Inc., of Statham, N.H., or Innovative Technology of Amesbury, Mass., may be useful for integration into various embodiments of a gas enclosure assembly according to the present teachings. Gas purification system  3134  can be used to purify one or more inert gases in enclosed printing system  500 C, for example, to purify the entire gas atmosphere within a gas enclosure assembly. As previously discussed herein, in order to circulate gas through gas purification loop  3130 , gas purification system  3134  can have a gas circulating unit, such as a fan, blower or motor, and the like. In that regard, a gas purification system can be selected depending on the volume of the enclosure, which can define a volumetric flow rate for moving an inert gas through a gas purification system. For various embodiments of gas enclosure system having a gas enclosure assembly with a volume of up to about 4 m 3 ; a gas purification system that can move about 84 m 3 /h can be used. For various embodiments of gas enclosure system having a gas enclosure assembly with a volume of up to about 10 m 3 ; a gas purification system that can move about 155 m 3 /h can be used. For various embodiments of a gas enclosure assembly having a volume of between about 52-114 m 3 , more than one gas purification system may be used. 
     Any suitable gas filters or purifying devices can be included in the gas purification system  3134  of the present teachings. In some embodiments, a gas purification system can comprise two parallel purifying devices, such that one of the devices can be taken off line for maintenance and the other device can be used to continue system operation without interruption. In some embodiments, for example, the gas purification system can comprise one or more molecular sieves. In some embodiments, the gas purification system can comprise at least a first molecular sieve, and a second molecular sieve, such that, when one of the molecular sieves becomes saturated with impurities, or otherwise is deemed not to be operating efficiently enough, the system can switch to the other molecular sieve while regenerating the saturated or non-efficient molecular sieve. A control unit can be provided for determining the operational efficiency of each molecular sieve, for switching between operation of different molecular sieves, for regenerating one or more molecular sieves, or for a combination thereof. As previously discussed herein, molecular sieves may be regenerated and reused. 
     Thermal regulation system  3140  of  FIG. 11  can include at least one chiller  3142 , which can have fluid outlet line  3141  for circulating a coolant into a gas enclosure assembly, and fluid inlet line  3143  for returning the coolant to the chiller. An at least one fluid chiller  3142  can be provided for cooling the gas atmosphere within enclosed printing system  500 C. For various embodiments of a gas enclosure system of the present teachings, fluid chiller  3142  delivers cooled fluid to heat exchangers within the enclosure, where inert gas is passed over a filtration system internal the enclosure. At least one fluid chiller can also be provided with enclosed printing system  500 C to cool heat evolving from an apparatus enclosed within enclosed printing system  500 C. For example, but not limited by, at least one fluid chiller can also be provided for enclosed printing system  500 C to cool heat evolving from a printing system. Thermal regulation system  3140  can comprise heat-exchange or Peltier devices and can have various cooling capacities. For example, for various embodiments of a gas enclosure system, a chiller can provide a cooling capacity of from between about 2 kW to about 20 kW. Various embodiments of a gas enclosure system can have a plurality of fluid chillers that can chill one or more fluids. In some embodiments, the fluid chillers can utilize a number of fluids as coolant, for example, but not limited by, water, anti-freeze, a refrigerant, and a combination thereof as a heat exchange fluid. Appropriate leak-free, locking connections can be used in connecting the associated conduits and system components. 
     As previously discussed herein, the present teachings disclose various embodiments of a gas enclosure system that can include a printing system enclosure defining a first volume and an auxiliary enclosure defining a second volume. Various embodiments of a gas enclosure system can have an auxiliary enclosure that can be sealably constructed as a section of gas enclosure assembly. According to systems and methods of the present teachings, an auxiliary enclosure can be sealable isolated from a printing system enclosure, and can be opened to an environment external a gas enclosure assembly without exposing a printing system enclosure to the external environment. Such physical isolation of an auxiliary enclosure to perform, for example, but not limited by, various printhead management procedures, can be done to eliminate or minimize the exposure of a printing system enclosure to contamination, such as a gas environment containing reactive species that may degrade materials used in a printing process, for example, but not limited by oxygen, ozone, water vapor and various organic vapors, as well as particulate contamination. Various printhead management procedures that can include measurement and maintenance procedures on a printhead device or a printhead can be done with little or no interruption of a printing process, thereby minimizing or eliminating gas enclosure system downtime. 
     For a gas enclosure system having a printing system enclosure defining a first volume and an auxiliary enclosure defining a second volume, both volumes can be readily integrated with gas circulation, filtration and purification components to form a gas enclosure system that can sustain an inert, substantially low-particle environment for processes requiring such an environment with little or no interruption of a printing process. According to various systems and methods of the present teachings, a printing system enclosure may be introduced to a level of contamination that is sufficiently low that a purification system can remove the contamination before it can affect a printing process. Various embodiments of an auxiliary enclosure can be a substantially smaller volume of the total volume of a gas enclosure assembly and can be readily integrated with gas circulation, filtration and purification components to form an auxiliary enclosure system that can rapidly recover an inert, of a low-particle environment after exposure to an external environment, thereby providing little or no interruption of a printing process. 
     Additionally, various embodiments of an auxiliary enclosure can be readily integrated with a dedicated set of environmental regulation system components, such as lighting, gas circulation and filtration, gas purification, and thermostating components. In that regard, various embodiments of a gas enclosure system that include an auxiliary enclosure that can be sealably isolated as a section of gas enclosure assembly can have a controlled environment that is set to be uniform with a first volume defined by a gas enclosure assembly housing a printing system. Further, various embodiments of a gas enclosure system including an auxiliary enclosure that can be sealably isolated as a section of gas enclosure assembly can have a controlled environment that is set to be different than the controlled environment of a first volume defined by a gas enclosure assembly housing a printing system. 
     While the examples above mentioning cooling capacities and chilling applications, the examples above can also be applied to applications where including buffering of substrates in a controlled environment, or for applications where circulating gas can be maintained at a temperature similar to other portions of the system, such as to avoid unwanted heat transfer from substrates being fabricated or to avoid disruption of temperature uniformity across a substrate or between substrates. 
       FIGS. 12A and 12B  illustrate generally examples of a gas enclosure system for integrating and controlling non-reactive gas and clean dry air (CDA) sources such as can be used to establish the controlled environment referred to in other examples described elsewhere herein, and such as can include a supply of pressurized gas for use with a floatation table.  FIG. 13A  and  FIG. 13B  illustrate generally examples of a gas enclosure system for integrating and controlling non-reactive gas and clean dry air (CDA) sources such as can be used to establish the controlled environment referred to in other examples described elsewhere herein, and such as can include a blower loop to provide, for example, pressurized gas and at least partial vacuum for use with a floatation table.  FIG. 14  illustrates generally a further example of a system for integrating and controlling one or more gas or air sources, such as to establish floatation control zones included as a portion of a floatation conveyance system. 
     Various examples described herein include enclosed modules that can be environmentally-controlled. Enclosure assemblies and corresponding support equipment can be referred to as a “gas enclosure system” and such enclosure assemblies can be constructed in a contoured fashion that reduces or minimizes an internal volume of a gas enclosure assembly, and at the same time provides a working volume for accommodating various footprints of printing system components, such as the deposition (e.g., printing), holding, loading, or treatment modules described herein. For example, a contoured gas enclosure assembly according to the present teachings can have a gas enclosure volume of between about 6 m 3  to about 95 m 3  for various examples of a gas enclosure assembly of the present teachings covering, for example, substrate sizes from Gen 3.5 to Gen 10. Various examples of a contoured gas enclosure assembly according to the present teachings can have a gas enclosure volume of, for example, but not limited by, of between about 15 m 3  to about 30 m 3 , which might be useful for printing of, for example, but not limited by, Gen 5.5 to Gen 8.5 substrate sizes or other substrate sizes. Various examples of an auxiliary enclosure can be constructed as a section of gas enclosure assembly and readily integrated with gas circulation and filtration, as well as purification components to form a gas enclosure system that can sustain a controlled, substantially low-particle environment for processes requiring such an environment. 
     As shown in  FIG. 12A  and  FIG. 13A , various examples of a gas enclosure system can include a pressurized non-reactive gas recirculation system. Various examples of a pressurized gas recirculation loop can utilize a compressor, a blower and combinations thereof. According to the present teachings, several engineering challenges were addressed in order to provide for various examples of a pressurized gas recirculation system in a gas enclosure system. First, under typical operation of a gas enclosure system without a pressurized non-reactive gas recirculation system, a gas enclosure system can be maintained at a slightly positive internal pressure (e.g., above atmospheric pressure) relative to an external pressure in order to safeguard against outside gas or air from entering the interior should any leaks develop in a gas enclosure system. For example, under typical operation, for various examples of a gas enclosure system of the present teachings, the interior of a gas enclosure system can be maintained at a pressure relative to the surrounding atmosphere external to the enclosure system, for example, of at least 2 mbarg, for example, at a pressure of at least 4 mbarg, at a pressure of at least 6 mbarg, at a pressure of at least 8 mbarg, or at a higher pressure. 
     Maintaining a pressurized gas recirculation system within a gas enclosure system can be challenging, as it presents a dynamic and ongoing balancing act regarding maintaining a slight positive internal pressure of a gas enclosure system, while at the same time continuously introducing pressurized gas into a gas enclosure system. Further, variable demand of various devices and apparatuses can create an irregular pressure profile for various gas enclosure assemblies and systems of the present teachings. Maintaining a dynamic pressure balance for a gas enclosure system held at a slight positive pressure relative to the external environment under such conditions can provide for the integrity of an ongoing fabrication process. For various examples of a gas enclosure system, a pressurized gas recirculation system according to the present teachings can include various examples of a pressurized gas loop that can utilize at least one of a compressor, an accumulator, and a blower, and combinations thereof. Various examples of a pressurized gas recirculation system that include various examples of a pressurized gas loop can have a specially designed pressure-controlled bypass loop that can provide internal pressure of a non-reactive gas in a gas enclosure system of the present teachings at a stable, defined value. In various examples of a gas enclosure system, a pressurized gas recirculation system can be configured to re-circulate pressurized gas via a pressure-controlled bypass loop when a pressure of a gas in an accumulator of a pressurized gas loop exceeds a pre-set threshold pressure. The threshold pressure can be, for example, within a range from between about 25 psig to about 200 psig, or more specifically within a range of between about 75 psig to about 125 psig, or more specifically within a range from between about 90 psig to about 95 psig. In that regard, a gas enclosure system of the present teachings having a pressurized gas recirculation system with various examples of a specially designed pressure-controlled bypass loop can maintain a balance of having a pressurized gas recirculation system in an hermetically sealed gas enclosure. 
     According to the present teachings, various devices and apparatuses can be disposed in the interior of a gas enclosure system and in fluid communication with various examples of a pressurized gas recirculation system. For various examples of a gas enclosure and system of the present teachings, the use of various pneumatically operated devices and apparatuses can provide low-particle generating performance, as well as being low maintenance. Exemplary devices and apparatuses that can be disposed in the interior of a gas enclosure system and in fluid communication with various pressurized gas loops can include, for example, but not limited by, one or more of a pneumatic robot, a substrate floatation table, an air bearing, an air bushing, a compressed gas tool, a pneumatic actuator, and combinations thereof. A substrate floatation table, as well as air bearings can be used for various aspects of operating a printing system in accordance with various examples of a gas enclosure system of the present teachings. For example, a substrate floatation table utilizing air-bearing technology can be used to transport a substrate into position in a printhead chamber, as well as to support a substrate during a printing process. 
     For example, as shown in  FIGS. 12A, 12B, 13A, and 13B , various examples of enclosed printing system  500 D and enclosed printing system  500 E can have external gas loop  3200  for integrating and controlling a non-reactive gas source  3201  and clean dry air (CDA) source  3203  for use in various aspects of operation of enclosed printing system  500 D and enclosed printing system  500 E. Enclosed printing system  500 D and enclosed printing system  500 E can also include various examples of an internal particle filtration and gas circulation system, as well as various examples of an external gas purification system, as described herein. Such examples of a gas enclosure system can include a gas purification system for purifying various reactive species from a gas. Some commonly used non-limiting examples of a non-reactive gas can include nitrogen, any of the noble gases, and any combination thereof. Various examples of a gas purification system according to the present teachings can maintain levels for each species of various reactive species, including various reactive atmospheric gases, such as water vapor, oxygen, ozone, as well as organic solvent vapors at 1000 ppm or lower, for example, at 100 ppm or lower, at 10 ppm or lower, at 1.0 ppm or lower, or at 0.1 ppm or lower. In addition to external loop  3200  for integrating and controlling gas source  3201  and CDA source  3203 , enclosed printing system  500 D and enclosed printing system  500 E can have compressor loop  3250 , which can supply gas for operating various devices and apparatuses that can be disposed in the interior of enclosed printing system  500 D and enclosed printing system  500 E. A vacuum system  3270  can be also be provided, such as in communication with gas enclosure assembly  1005  through line  3272  when valve  3274  is in an open position. 
     Compressor loop  3250  of  FIG. 12A  can include compressor  3262 , first accumulator  3264  and second accumulator  3268 , which are configured to be in fluid communication. Compressor  3262  can be configured to compress gas withdrawn from gas enclosure assembly  1005  to a desired pressure. An inlet side of compressor loop  3250  can be in fluid communication with gas enclosure assembly  1005  via gas enclosure assembly outlet  3252  through line  3254 , having valve  3256  and check valve  3258 . Compressor loop  3250  can be in fluid communication with gas enclosure assembly  1005  on an outlet side of compressor loop  3250  via external gas loop  3200 . Accumulator  3264  can be disposed between compressor  3262  and the junction of compressor loop  3250  with external gas loop  3200  and can be configured to generate a pressure of 5 psig or higher. Second accumulator  3268  can be in compressor loop  3250  for providing dampening fluctuations due to compressor piston cycling at about 60 Hz. For various examples of compressor loop  3250 , first accumulator  3264  can have a capacity of between about 80 gallons to about 160 gallons, while second accumulator can have a capacity of between about 30 gallons to about 60 gallons. According to various examples of enclosed printing system  500 D, compressor  3262  can be a zero ingress compressor. Various types of zero ingress compressors can operate without leaking atmospheric gases into various examples of a gas enclosure system of the present teachings. Various examples of a zero ingress compressor can be run continuously, for example, during a fabrication process utilizing the use of various devices and apparatuses requiring compressed gas. 
     Accumulator  3264  can be configured to receive and accumulate compressed gas from compressor  3262 . Accumulator  3264  can supply the compressed gas as needed in gas enclosure assembly  1005 . For example, accumulator  3264  can provide gas to maintain pressure for various components of gas enclosure assembly  1005 , such as, but not limited by, one or more of a pneumatic robot, a substrate floatation table, an air bearing, an air bushing, a compressed gas tool, a pneumatic actuator, and combinations thereof. As shown in  FIG. 12A  for enclosed printing system  500 D, gas enclosure assembly  1005  can have printing system  2005  enclosed therein. As schematically depicted in  FIG. 12A , printing system  2005  can be supported by printing system base  2150 , which can be a granite stage. Printing system base  2150  can support a substrate support apparatus, such as a chuck, for example, but not limited by, a vacuum chuck, a substrate floatation chuck having pressure ports, and a substrate floatation chuck having vacuum and pressure ports. In various examples of the present teachings, a substrate support apparatus can be a substrate floatation table, such as substrate floatation table  2250 . Substrate floatation table  2250  can be used for the frictionless support of a substrate. In addition to a low-particle generating floatation table, for frictionless Y-axis conveyance of a substrate, printing system  2005  can have a Y-axis motion system utilizing air bushings. 
     Additionally, printing system  2005  can have at least one X,Z-axis carriage assembly with motion control provided by a low-particle generating X-axis air bearing assembly. Various components of a low-particle generating motion system, such as an X-axis air bearing assembly, can be used in place of, for example, various particle-generating linear mechanical bearing systems. For various examples of a gas enclosure and system of the present teachings, the use of a variety of pneumatically operated devices and apparatuses can provide low-particle generating performance, as well as being low maintenance. Compressor loop  3250  can be configured to continuously supply pressurized gas to various devices and apparatuses of enclosed printing system  500 D. In addition to a supply of pressurized gas, substrate floatation table  2250  of printing system  2005 , which utilizes air bearing technology, also utilizes vacuum system  3270 , which is in communication with gas enclosure assembly  1005  through line  3272  when valve  3274  is in an open position. 
     A pressurized gas recirculation system according to the present teachings can have pressure-controlled bypass loop  3260  as shown in  FIG. 12A  for compressor loop  3250 , which acts to compensate for variable demand of pressurized gas during use, thereby providing dynamic balance for various examples of a gas enclosure system of the present teachings. For various examples of a gas enclosure system according to the present teachings, a bypass loop can maintain a constant pressure in accumulator  3264  without disrupting or changing the pressure in enclosure  1005 . Bypass loop  3260  can have first bypass inlet valve  3261  on an inlet side of bypass loop, which is closed unless bypass loop  3260  is used. Bypass loop  3260  can also have back pressure regulator  3266 , which can be used when second valve  3263  is closed. Bypass loop  3260  can have second accumulator  3268  disposed at an outlet side of bypass loop  3260 . For examples of compressor loop  3250  utilizing a zero ingress compressor, bypass loop  3260  can compensate for small excursions of pressure that can occur over time during use of a gas enclosure system. Bypass loop  3260  can be in fluid communication with compressor loop  3250  on an inlet side of bypass loop  3260  when bypass inlet valve  3261  is in an opened position. When bypass inlet valve  3261  is opened, gas shunted through bypass loop  3260  can be recirculated to the compressor if gas from compressor loop  3250  is not in demand within the interior of gas enclosure assembly  1005 . Compressor loop  3250  is configured to shunt gas through bypass loop  3260  when a pressure of the gas in accumulator  3264  exceeds a pre-set threshold pressure. A pre-set threshold pressure for accumulator  3264  can be from between about 25 psig to about 200 psig at a flow rate of at least about 1 cubic feet per minute (cfm), or from between about 50 psig to about 150 psig at a flow rate of at least about 1 cubic feet per minute (cfm), or from between about 75 psig to about 125 psig at a flow rate of at least about 1 cubic feet per minute (cfm) or between about 90 psig to about 95 psig at a flow rate of at least about 1 cubic feet per minute (cfm). 
     Various examples of compressor loop  3250  can utilize a variety of compressors other than a zero ingress compressor, such as a variable speed compressor or a compressor that can be controlled to be in either an on or off state. As previously discussed herein, a zero ingress compressor ensures that no atmospheric reactive species can be introduced into a gas enclosure system. As such, any compressor configuration preventing atmospheric reactive species from being introduced into a gas enclosure system can be utilized for compressor loop  3250 . According to various examples, compressor  3262  of enclosed printing system  500 D can be housed in, for example, but not limited by, an hermetically-sealed housing. The housing interior can be configured in fluid communication with a source of gas, for example, the same gas that forms the gas atmosphere for gas enclosure assembly  1005 . For various examples of compressor loop  3250 , compressor  3262  can be controlled at a constant speed to maintain a constant pressure. In other examples of compressor loop  3250  not utilizing a zero ingress compressor, compressor  3262  can be turned off when a maximum threshold pressure is reached, and turned on when a minimum threshold pressure is reached. 
     In  FIG. 13A  for enclosed printing system  500 E, blower loop  3280  utilizing vacuum blower  3290  is shown for the operation of substrate floatation table  2250  of printing system  2005 , which are housed in gas enclosure assembly  1005 . As previously discussed herein for compressor loop  3250 , blower loop  3280  can be configured to continuously supply pressurized gas to a substrate floatation table  2250  of printing system  2005 . 
     Various examples of a gas enclosure system that can utilize a pressurized gas recirculation system can have various loops utilizing a variety of pressurized gas sources, such as at least one of a compressor, a blower, and combinations thereof. In  FIG. 13A  for enclosed printing system  500 E, compressor loop  3250  can be in fluid communication with external gas loop  3200 , which can be used for the supply of gas for high consumption manifold  3225 , as well as low consumption manifold  3215 . For various examples of a gas enclosure system according to the present teachings as shown in  FIG. 13A  for enclosed printing system  500 E, high consumption manifold  3225  can be used to supply gas to various devices and apparatuses, such as, but not limited by, one or more of a substrate floatation table, a pneumatic robot, an air bearing, an air bushing, and a compressed gas tool, and combinations thereof. For various examples of a gas enclosure system according to the present teachings, low consumption  3215  can be used to supply gas to various apparatuses and devises, such as, but not limited by, one or more of an isolator, and a pneumatic actuator, and combinations thereof. 
     For various examples of enclosed printing system  500 E of  FIG. 13A  and  FIG. 13B , a blower loop  3280  can be utilized to supply pressurized gas to various examples of substrate floatation table  2250 . In addition to a supply of pressurized gas, substrate floatation table  2250  of printing system  2005 , which utilizes air bearing technology, also utilizes blower vacuum  3290 , which is in communication with gas enclosure assembly  1005  through line  3292  when valve  3294  is in an open position. Housing  3282  of blower loop  3280  can maintain first blower  3284  for supplying a pressurized source of gas to substrate floatation table  2250 , and second blower  3290 , acting as a vacuum source for substrate floatation table  2250 , which is housed in a gas environment in gas enclosure assembly  1005 . Attributes that can make blowers suitable for use as a source of either pressurized gas or vacuum for various examples a substrate floatation table include, for example, but not limited by, that they have high reliability; making them low maintenance, have variable speed control, and have a wide range of flow volumes; various examples capable of providing a volume flow of between about 100 m 3 /h to about 2,500 m 3 /h. Various examples of blower loop  3280  additionally can have first isolation valve  3283  at an inlet end of blower loop  3280 , as well as check valve  3285  and a second isolation valve  3287  at an outlet end of blower loop  3280 . Various examples of blower loop  3280  can have adjustable valve  3286 , which can be, for example, but not limited by, a gate, butterfly, needle or ball valve, as well as heat exchanger  3288  for maintaining gas from blower loop  3280  to substrate floatation table  2250  at a defined temperature. 
       FIG. 13A  depicts external gas loop  3200 , also shown in  FIG. 12A , for integrating and controlling gas source  3201  and clean dry air (CDA) source  3203  for use in various aspects of operation of enclosed printing system  500 D of  FIG. 12A  and enclosed printing system  500 E of  FIG. 13A . External gas loop  3200  of  FIG. 12A  and  FIG. 13A  can include at least four mechanical valves. These valves include first mechanical valve  3202 , second mechanical valve  3204 , third mechanical valve  3206 , and fourth mechanical valve  3208 . These various valves are located at positions in various flow lines that allow control of both a non-reactive gas and an air source such as clean dry air (CDA). According to the present teachings, a non-reactive gas can be any gas that does not undergo a chemical reaction under a defined set of conditions. Some commonly used non-limiting examples of non-reactive gas can include nitrogen, any of the noble gases, and any combination thereof. From a house gas source  3201 , a house gas line  3210  extends. House gas line  3210  continues to extend linearly as low consumption manifold line  3212 , which is in fluid communication with low consumption manifold  3215 . A cross-line first section  3214  extends from a first flow juncture  3216 , which is located at the intersection of house gas line  3210 , low consumption manifold line  3212 , and cross-line first section  3214 . Cross-line first section  3214  extends to a second flow juncture  3218 . A compressor gas line  3220  extends from accumulator  3264  of compressor loop  3250  and terminates at second flow juncture  3218 . A CDA line  3222  extends from a CDA source  3203  and continues as high consumption manifold line  3224 , which is in fluid communication with high consumption manifold  3225 . A third flow juncture  3226  is positioned at the intersection of a cross-line second section  3228 , clean dry air line  3222 , and high consumption manifold line  3224 . Cross-line second section  3228  extends from second flow juncture  3218  to third flow juncture  3226 . Various components that are high consumption can be supplied CDA during maintenance, by means high consumption manifold  3225 . Isolating the compressor using valves  3204 ,  3208 , and  3230  can prevent reactive species, such as ozone, oxygen, and water vapor from contaminating a gas within the compressor and accumulator. 
     By contrast with  FIGS. 12A and 13A ,  FIGS. 12B and 13B  illustrate generally a configuration wherein a pressure of gas inside the gas enclosure assembly  1005  can be maintained within a desired or specified range, such as using a valve coupled to a pressure monitor, P, where the valve allows gas to be exhausted to another enclosure, system, or a region surrounding the gas enclosure assembly  1005  using information obtained from the pressure monitor. Such gas can be recovered and re-processed as in other examples described herein. As mentioned above, such regulation can assist in maintaining a slight positive internal pressure of a gas enclosure system, because pressurized gas is also contemporaneously introduced into the gas enclosure system. Variable demand of various devices and apparatuses can create an irregular pressure profile for various gas enclosure assemblies and systems of the present teachings. Accordingly, the approach shown in  FIGS. 12B and 13B  can be used in addition or instead of other approaches described herein such as to assist in maintaining a dynamic pressure balance for a gas enclosure system held at a slight positive pressure relative to the environment surrounding the enclosure. 
       FIG. 14  illustrates generally a further example of a system  500 F for integrating and controlling one or more gas or air sources, such as to establish floatation control zones included as a portion of a floatation conveyance system. Similar to the examples of  FIG. 3 ,  FIG. 13A  and  FIG. 13B ,  FIG. 14  illustrates generally floatation table  2250 . Additionally, shown in the illustrative example of  FIG. 14  are an input region  2201  and an output region  2203 . The regions  2201 ,  2200 ,  2203  are referred to as input, printing, and output for illustration only. Such regions can be used for other processing steps, such as conveyance of a substrate, or support of a substrate such as during one or more of holding, drying, or thermal treatment of the substrate in one or more other modules. In the illustration of  FIG. 14 , a first blower  3284 A is configured to provide pressurized gas in one or more of the input or output regions  2201  or  2203  of a floatation table apparatus. Such pressurized gas can be temperature controlled such as using a first chiller  142 A coupled to a first heat exchanger  1502 A. Such pressurized gas can be filtered using a first filter  1503 A. A temperature monitor  8701 A can be coupled to the first chiller  142  (or other temperature controller). 
     Similarly, a second blower  3284 B can be coupled to the printing region  2202  of the floatation table. A separate chiller  142 B can be coupled to a loop including a second heat exchanger  1502 B and a second filter  1503 B. A second temperature monitor  8701 B can be used to provide independent regulation of the temperature of pressurized gas provided by the second blower  3284 B. In this illustrative example, as described herein for  FIG. 3 , the input and output regions  2201  and  2203  are supplied with positive pressure, but the printing region  2202  can include use of a combination of positive pressure and vacuum control to provide precise control over the substrate position. For example, using such a combination of positive pressure and vacuum control, the substrate can be exclusively controlled using the floating gas cushion provided by enclosure printing system  500 F in the zone defined by the printing region  2202 . The vacuum can be established by a third blower  3290 , such as also provided at least a portion of the make-up gas for the first and second blowers  3284 A or  3284 B within the blower housing  3282 . 
     It should be understood that various alternatives to the embodiments of the disclosure described herein may be employed in practicing the disclosure. For example, embodiments of an enclosed printing system according to the present teachings can be useful for patterned area printing of substrates in the manufacture of a variety of devices and apparatuses in a wide range of technology areas, for example, but not limited by, OLED displays, OLED lighting, organic photovoltaics, Perovskite solar cells, and organic semiconductor circuits. Additionally, vastly different arts such as chemistry, biotechnology, high technology and pharmaceutical arts may benefit from the present teachings. Printing is used to exemplify the utility of various embodiments of a gas enclosure system according to the present teachings. Various embodiments of a gas enclosure system that may house a printing system can provide features such as, but not limited by, sealing providing an hermetic-sealed enclosure through cycles of construction and deconstruction, minimization of enclosure volume, and ready access from the exterior to the interior during processing, as well as during maintenance. Such features of various embodiments of a gas enclosure system may have an impact on functionality, such as, but not limited by, structural integrity providing ease of maintaining low levels of reactive species and particulate matter during processing, as well as rapid enclosure-volume turnover minimizing downtime during maintenance cycles. As such, various features and specifications providing utility for substrate printing may also provide benefit to a variety of technology areas. 
     While embodiments of the present disclosure have been shown and described herein, it will be obvious to those skilled in the art that such embodiments are provided by way of example only. Numerous variations, changes, and substitutions will now occur to those skilled in the art without departing from the disclosure. It is intended that the following claims define the scope of the disclosure and that methods and structures within the scope of these claims and their equivalents be covered thereby.