Patent Publication Number: US-10759188-B2

Title: System for providing multiple surface treatments to three-dimensional objects prior to printing

Description:
TECHNICAL FIELD 
     This disclosure is directed to printers and, more particularly, to systems for treating the surfaces of three-dimensional (3D) objects to prepare the surfaces for printing. 
     BACKGROUND 
     Printers have been developed that can print text and graphics with multiple colors directly onto the surface of 3D objects. These printers, known as direct-to-object (DTO) printers, enable a small number of objects, even a single object, to be printed. These printers are particularly advantageous in retail environments where unprinted objects can be kept and then printed to provide customized appearances to the objects. This flexibility enables an unprinted inventory of objects, such as various types of balls used in various sports, to be kept at the location and then printed with the logos of particular teams. Consequently, an inventory of objects with a particular logo or color scheme is not required. 
     One of the issues related to printing objects with a DTO printer is the wide variety of materials, such as metal, plastics, fabrics, and the like, that are used to make the 3D objects. These different materials have a corresponding wide range of surface energies. The surface energies of many of these materials adversely impact the adhesion and durability of ink images on these surfaces. Some of these materials require some type of surface pretreatment to increase the surface energy of the material for durable printing. Typical surface treatment processes include but are not limited to: (1) general cleaning using detergents or solvents, (2) texturing using sanding, sandblasting, plasma etching or the like, (3) low pressure plasma exposure or plasma etching, (4) atmospheric pressure plasma treatments, such as corona, chemical corona, blown arc, plasma jet, and blown ion processes, (5) the application of chemical primers, and (6) flame treatment of surfaces. 
     Currently, many facilities having DTO printers manually treat the objects prior to printing. Objects requiring only hand buffing and an isopropyl alcohol (IPA) wipe are amendable to manual treatment, while other objects requiring more involved treatments, such as significant exposure time in a low pressure plasma chamber, are not as amenable. Other objects may require a series of different types of surface treatment to achieve optimal results. For instance, some objects are best prepared for printing by hand buffing the object, then applying an IPA wipe followed by flame treatment of the surface. The useful lifetime of surface treatments is variable and range from a few minutes to months depending on the material treated, the process used to treat the material, and the environment in which the object is stored. The general rule of thumb is that the more aggressive the treatment is to get an ink to wet and adhere to a material, the shorter the duration of the treatment. Therefore, a system that successfully treats a wide range of materials, automates the surface treatment procedure to remove human variability and exposure to chemicals, and treats the objects immediately prior to printing would be useful. 
     SUMMARY 
     An object surface treatment system provides a plurality of surface treatments to raise the surface energies of objects to improve the printing of the objects with DTO printers. The system includes a holder configured to secure an object within the holder, and a plurality of surface treatment devices, each surface treatment device being configured to treat a surface of the object within the holder differently than each of the other surface treatment devices in the plurality of surface treatment devices. 
     Another embodiment of the object surface treatment system enables the surface energy of objects made from a wide range of materials to be raised immediately prior to printing by the printer. The system includes a holder configured to secure an object within the holder, and a plurality of surface treatment devices, each surface treatment device being configured to treat a surface of the object within the holder differently than each of the other surface treatment devices in the plurality of surface treatment devices. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The foregoing aspects and other features of an object surface treatment system that provides a plurality of surface treatments to raise the surface energies of objects to improve the printing of the objects with DTO printers are explained in the following description, taken in connection with the accompanying drawings. 
         FIG. 1  is a schematic diagram of a system configured to apply multiple surface treatments to multiple types of object materials immediately prior to the objects being printed. 
         FIG. 2  is a flow diagram that can be performed by the system of  FIG. 1 . 
         FIG. 3  is a block diagram of a printer integrated with the system of  FIG. 1 . 
     
    
    
     DETAILED DESCRIPTION 
     For a general understanding of the environment for the device disclosed herein as well as the details for the device, reference is made to the drawings. In the drawings, like reference numerals designate like elements. 
     As used herein, the word “printer” encompasses any apparatus that produces images with one or more marking materials on media or objects. As used herein, the term “process direction” (P) refers to a direction of movement of an object through a printer having at least one printhead or through a surface treatment system having a plurality of surface treatment devices. As used herein, the term “cross-process” direction (CP) refers to an axis that is perpendicular to the process direction. As used in this document, the word “surface treatment” means any process that raises the surface energy of a material to improve the wettability and durability of ink on the surface. 
       FIG. 1  is a schematic diagram of a system configured to operate a plurality of surface treatment devices to apply multiple surface treatments to multiple types of object materials immediately prior to the objects being printed. The system includes a housing  104  in which a surface treatment system  108  is configured to treat the surfaces of objects  120  carried by a holder  116 . In  FIG. 1 , the object  120  is a water bottle, but the holder can be configured to secure other types of objects. As used in this document, the word “secure” means a structure configured to maintain an object in a particular orientation until the object is released from the structure. The housing  104  includes walls that enclose the system  108 , the holder  116 , and the object  120  to contain the materials used to treat the surface of an object. One wall of the housing  104  includes a vent opening  124  in which a fan  128  is positioned to pull materials and fumes from an overspray structure  136  through a filter  132 . Thus, the materials used and the fumes produced by the materials can be removed from the air surrounding the object  120  and filtered before being exhausted from the housing  104 . The system  100  includes a plurality of surface treatment devices that are operated independently to apply surface treatments to the object  120 . As used in this document, the term “operated independently” or its equivalent means to operate a device in a plurality of devices while the other devices in the plurality are not operated. 
     With continued reference to  FIG. 1 , the system  108  includes a controller  140  that is operatively connected to a combustible material source  144  for a flame surface treatment device  156 , a multi-input valve  148  for a chemical surface treatment device  160 , and a multi-input valve  152  for a gas plasma surface treatment device  164 , and actuators  168  for moving a surface treatment device head  172  along a support member  176  and manipulating the position of the object  120 . The flame surface treatment device  156 , the chemical surface treatment device  160 , and the gas plasma surface treatment device  163  are integrated in surface treatment device head  172  and are configured with actuators to bidirectionally movement in the cross-process direction C-P that is perpendicular to the bidirectional process direction P along the support member  176 . This bidirectional movement of the various surface treatment devices is performed by the controller  140  operating actuators internal to the surface treatment device head  172 . The actuators are operatively connected to the devices in a one-to-one correspondence. Thus, after an object  120  is secured within holder  116 , the controller  140  can operate an actuator  168  to move the surface treatment head  172  bidirectionally along the support member  176  and to operate another actuator  168  to rotate the holder  116  and the object  120  to present various surfaces to the surface treatment head  172  for treatment. The controller  140  is also operatively connected to the surface treatment device head  172  to operate the flame surface treatment device, the chemical surface treatment device, and the gas plasma surface treatment device independently of one another so the controller can operate less than all of the surface treatment devices to treat an object surface. That is, the controller can operate all of the surface treatment devices or as few as one surface treatment device to treat the surface of an object. 
     As shown in  FIG. 1 , the combustible source  144  is pneumatically connected to the flame surface treatment device  156 . In response to the controller  140  operating a valve  142  in the line to the device  156  to open, a combustible fluid or gas from the pressurized source  144  flows to the flame treatment device  156  where an ignitor  154  of the device  156  is operated to form a flame for treatment of an object surface. When the flame treatment is complete, the controller closes the valve  142  to terminate the flow of the combustible substance to the device  156 . As used in this document, the term “combustible substance” means a gas or fluid that flows under pressure and that ignites to form a flame. Such materials include propane and natural gas, for example. 
     The multi-input valve  148  is pneumatically connected to a plurality of sources of chemical surface treatment materials and a source of a flush fluid. The controller  140  operates the multi-input valve  148  to couple one of the sources of chemical surface treatment materials exclusively to the chemical surface treatment device  160 . As used in this document, “chemical surface treatment device” means any device that emits a substance so the substance contacts the surface of the object being treated and increases the surface energy of the object. Such a device can be, for example, a nozzle, a spray head, an applicator, or a brush. As used in this document, the term “couple exclusively” or its equivalent means coupling a source in a plurality of sources to a device while the remaining sources in the plurality are not in direct fluid communication with the device. By selectively operating the chemical surface treatment device  160  as the actuators  168  move the head  172  and rotate the object  120 , the chemical discharged from the chemical surface treatment device  160  can be applied to different areas of the object surface selectively. After one or more chemicals are appropriately applied to the object surface and the object is removed from the position opposite the head  172 , the controller operates the multi-input valve  148  to couple the source of flush fluid to the chemical surface treatment device  160 . The flush fluid is a material that removes residual chemical in the line connected the valve  148  and the device  160  as well as residual chemicals in the device. As used in this document, “chemical surface treatment material” means any substance applied to another material that increases the surface energy of the material. Such materials include, for example, BondAid1 and BondAid2 Adhesion Promoters, both available from the Triangle division of INX International Ink Co. of Schaumsburg, Ill., and ZE680 and ZE1000 Adhesion Promoters from FujiFilm North America Corporation, Graphic Systems Division. As used in this document, “flush fluid” refers to any material that successfully removes a chemical surface treatment material from the line to the device  160  and from the device  160  as well. Such fluids include, for example, water, alcohols, hydrocarbons, and the like. 
     The multi-input valve  152  is pneumatically connected to a plurality of sources of plasma gases that are useful to produce plasma for surface treatment of objects. The controller  140  operates the multi-input valve  152  to couple one of the sources of plasma gases to the plasma surface treatment device  164  exclusively. As used in this document, “plasma surface treatment device” means a device that applies an electric voltage or current to a plasma gas to produce a plasma that increases the surface energy of a material. Such a device can be, for example, a plasma generator or a plasma probe. The controller  140  also operates a voltage or current source in the device  164  to form the plasma with the plasma gas released to the device. By selectively operating the plasma surface treatment device  164  as the actuators  168  move the head  172  and rotate the object  120 , the plasma discharged from the plasma surface treatment device  160  can be applied to different areas of the object surface selectively. After one or more plasmas is appropriately applied to the object surface, the controller operates the multi-input valve  152  to decouple the connected source of plasma gas from the plasma surface treatment device  164 . As used in this document, “plasma gas” means any gas that produces plasma in the presence of an electric voltage or current. Such gases include, for example, oxygen, argon, nitrogen, hydrofluorocarbons, and carbon tetrachloride. 
     The controller  140  can be configured with programmed instructions stored in a memory operatively connected to the controller to enable the controller to perform different types of surface treatments on one or more objects. A controller so configured can perform the process  200  shown in  FIG. 2 . To enable the performance of this process in one embodiment of the system  100  shown in  FIG. 1 , a user interface  182  is provided so a user can input a code that identifies an object and the material of which the object is made. Other methods of entering a code include a bar code reader or other indicia detecting sensors. 
     With reference to  FIG. 2 , the process  200  begins with the controller comparing a code entered for an object with codes stored in the memory connected to the controller (block  204 ). If the code corresponds to one stored in the memory, the controller obtains data regarding the physical configuration of the object and the one or more treatments to be applied to the object (block  208 ). Otherwise, the process performs exception processing (block  206 ) to handle the lack of a stored code corresponding to the entered code. The controller operates the system  104  as described above to apply at least one treatment to at least one area of the object surface (block  212 ). This processing can include multiple treatments being applied to one or more same areas of the object or multiple treatments being applied to different areas of the object. Once the surface treatment of the object is complete (block  214 ), the controller generates a signal indicating the object is ready for printing (block  216 ). This signal can activate a display or annunciator on the user interface  182  or other known device for indicating a system status. After the treated object leaves the system  104 , the controller determines whether any chemical surface treatments were performed (block  220 ). If any were, then the controller operates the multi-input valve  148  to flush the line to the chemical surface treatment device  160  and the device (block  224 ). The controller then generates a signal indicative that the system  104  is ready for treatment of another object (block  228 ). 
       FIG. 3  is a block diagram of a printer  300  that integrates a printing system  308  with the surface treatment system  104 . In this printer, the holder  116  is mounted for movement along support member  304  and the controller  140  operates actuator  168  to move the holder along the member. In this printer, the support member extends out of the system  104  to position the holder  116  at an initial position where an object can be mounted in the holder for movement into the system  104 . After the object is moved into the system  104 , the system is operated as previously described to treat the surface of the object. When surface treatment of the object is completed, the controller operates actuator  168  to directly convey the object from the system  104  and into the printing system  308 . As used in this document, the term “directly conveyed” means a movement of an object from a surface treatment system to a printing system without removal of the object from the holder used to secure the object within the surface treatment system. Printing system  308  is a DTO printer having a controller that detects the entry of the treated object and operates the printer to eject marking materials on the treated surface of the object to form ink images on the object. The printing system  308  removes the object from the holder  116  and ejects the printed object from the printer. The member  304  can be configured with at least two holders to enable a treated object to be printed, while an untreated object is subjected to at least one of the treatment processes in system  104 . If the member  304  includes at least three holders  116 , then the system  104  and the printing system  308  of the printer  300  are configured for continuous operation to treat and print a limited run of similar objects because an untreated object can be positioned in a holder  116  while another untreated object is being treated within system  104  and a treated object is being printed in printing system  308  and operation of the actuator  168  moves the holder  116  to feed position below the treatment system  104  while the other two holders  116  are moved into the treatment system and the printing system. 
     It will be appreciated that variants of the above-disclosed and other features and functions, or alternatives thereof, may be desirably combined into many other different systems, applications or methods. Various presently unforeseen or unanticipated alternatives, modifications, variations or improvements may be subsequently made by those skilled in the art that are also intended to be encompassed by the following claims.