Method for managing wax on a print having a toner image therein

In one aspect a method for operating a printer is provided in which a toner image is formed on a receiver using a toner having a polymeric binder and a wax. A contact surface is used to apply heat and pressure to heat the toner at least to a glass transition temperature for the toner and to heat the wax to at least an incorporated melting temperature. The toner image is allowed to cool below a glass transition temperature of the toner to form a fused toner image having a viewing surface and the wax is allowed to cool below the melting temperature for the wax so that after cooling the viewing surface has first portions with wax globules and second portions without wax globules. The viewing surface is wiped to move at least some of the wax from the wax globules in the first portions onto the second portions.

CROSS REFERENCE TO RELATED APPLICATIONS

FIELD OF THE INVENTION

This invention pertains to the field of printing.

BACKGROUND OF THE INVENTION

In toner printing a pattern of toner particles is formed and transferred to a receiver. The transferred toner particles are then fused to create adhesive bonds between the toner particles and between the toner particles and the receiver. In most commercial applications, fusing is performed using a process known as contact fusing. In a contact fusing system, the pattern of toner particles and the receiver are passed through a nip between a heated roller and a pressure roller. The heated roller and the pressure roller are biased toward each other and press the pattern of toner particles and the receiver together while the heated roller heats the toner particles and the receiver. The pressure and heat applied during fusing creates the adhesive bonds that form a fused toner image that is bound to the receiver.

Adhesive bonds also arise between the toner particles and the heated roller during contact fusing. Where the adhesive bonds between the toner particles and the heated roller are weaker than the adhesive bonds between the toner particles within the toner image and the adhesive bonds between the toner particles and the receiver, the toner particles separate from contact with the heated roller, remain on the receiver, and cool to form the fused toner image. However, where the adhesive bonds between the heated roller and the toner particles are stronger than the adhesive bonds between the toner particles in the toner image or when the adhesive bonds between the heated roller and the toner particles are stronger than the adhesive bonds between the toner particles, and the receiver, toner particles can separate from the toner image and adhere to the heated roller. This is known as toner offset. Toner offset creates unwelcome artifacts in the toner image being fused by removing toner necessary for the toner image that is being fused. Further, the toner that remains on the heated roller creates unwelcome artifacts in subsequently fused images by transferring to later toner prints or by forming relief patterns in such later formed toner images.

In some toner printers, elongated belts are used for fusing that have the effect of reducing toner offset. One example of this is described in U.S. Pat. No. 5,256,507 (issued Oct. 26, 1993, in the name of Aslam et al). As is described in the '507 patent, an elongated web is heated to fuse the toner image and then cooled to facilitate ready separation of the receiver member with the toner image fixed thereto from the elongated web. The elongated web arrangement also serves to increase the glossiness of the toner image. As a result, this arrangement is particularly useful for multi-color toner image fusing.

Alternatively, other toner printers apply a fusing oil to the heated roller in order to reduce the adhesion between the heated roller and the toner. However, the use of such oil creates new press operating requirements by requiring additional handling of the oil and by requiring procedures and equipment to ensure that oil is applied in a consistent manner. Additionally, at least some of the fusing oil can transfer from the heated roller onto the print creating a print having image quality and handling problems.

In another alternative, toner printers have been developed that use toner particles that incorporate a wax. During fusing such toner particles are heated at least to a glass transition temperature of the toner and to an incorporated melting temperature of the incorporated wax. This causes the wax to liquefy and to separate from the pattern forming material to form a slip layer between the toner particles and a heated fuser roller. The slip layer reduces extent of adhesive bonds between the heated fuser roller and the toner particles and lowers the likelihood of toner offset. However, after fusing, the wax remains on the toner image and creates gloss and image density variations that can lower the perceived quality of toner images made using toners of this type. This is a particular problem with high gloss images that require high fusing temperatures.

One alternative approach is to remove wax from the toner image during fusing. For example, JP2005043532A entitled: “A fixing apparatus and an image forming device” describes a fixing apparatus having a heating roller wherein any surplus amount of wax is removed from the toner image by being drawn into pores in the heating roller. Similarly, JP2006091146A entitled: “An Image Forming Device and a Fixing Apparatus” describes toner image is formed using the toner containing a resin binder, a coloring material and the wax for improving the releasability. In these publications a wax bearing toner is transferred onto a recording sheet and the toner is fixed by a fixing device under heat and pressure. The fixing device has a heating roller in the form of a hollow cylindrical member made of a metal and has a large number of pores extending from the peripheral face of the heating roller and to the hollow part thereof. According to the '532 publication, when toner is heated, the melting wax forms a layer and is drawn into the pores by capillary action and removed. The wax is absorbed by a glass fiber layer formed inside the heating roller and held. The '532 publication further suggests that since the excess of wax is removed from the surface of the toner image, the gloss unevenness is restrained without making the toner image remarkably highly glossy even when the toner image is suddenly cooled after fixing.

Another approach is shown in JP2005266079A entitled: “Image Forming Apparatus, Wax Removal Device and Image Forming Method”. The '079 publication describes the use of a wax removal part that allows a blade to contact the surface of a recording medium that is at a temperature range not lower than the melting point of the wax included in toner and lower than the melting point of the toner material. The blade removes the melted wax on the surface of the recording medium. A distance between the fixing device and the blade is determined so that the recording medium causes a temperature drop in accordance with the conveyance and the temperature of the surface falls into the temperature range.

Another publication, JP 2002-091205A entitled: “Image forming apparatus” describes another printer with a wax removal system. In one embodiment the wax removal system has a rolling-up (continuous) type web cleaning device and a film anchorage device that positions the web for cleaning. According to the '205 publication, the wax on a recording medium can fully be cleaned by placing a web on a cleaning roller and rolling the cleaning roller in a direction that is the reverse of a direction of movement of a recording medium. The web can be a porous body material which comprises a natural or natural fibrous body or polyester, polypropylene, polyethylene, etc. However, other webs can be used.

The '205 publication also notes in order to acquire a picture without the further loss of density and gloss caused by wax, the cooling temperature in an exfoliation point is lower than the softening temperature of this recording-medium resin, and it is desirable that it is higher than the melting point of a wax. The '205 publication further notes that it will become granular (the wax which began to melt from a toner in this intermediate transfer body and this recording-medium interface) and will adhere on this recording medium after exfoliation if it exfoliates at a temperature lower than wax melting point temperature under the state where this intermediate transfer body and this recording medium touch.

In general then, the approaches of the '507, '146, '079 and '205 publications attempt to resolve the wax problem by cleaning wax from the surface of the toner image. However, it will be appreciated that attempting to fully clean wax from the surface of a toner image can create a risk of damaging the toner image as generally such cleaning processes involve cleaning structures that are held against the toner image while applying cleaning forces to remove the wax from the toner image. Such cleaning processes pose a particular risk of damaging portions of the toner image that have significant variations in toner stack heights such as regions of high density color where many different types of toner are applied or in regions where toner is applied to build toner stack heights that are high enough to create tactile effects.

The risks of damaging the toner image are particularly acute when such cleaning is performed when the toner is at an elevated temperature. Yet in each of the '536, '136, '079 and '205 publications wax removal is performed when the wax is heated to a temperature sufficient to liquefy the wax. As the wax is in intimate contact with the toner image, this necessarily involves removing wax when the toner image is at an elevated temperature and is more vulnerable to damage.

For example, in the '536 and '136 publications, wax is cleaned at the fusing nip while the wax is in a liquid form and the toner is at or above the glass transition temperature for the toner. These in-the-nip cleaning approaches can be compromised by the risk that the fusing process will interfere with the wax cleaning process, and by the risk that the wax cleaning process will reduce the effectiveness of the fusing process. These in-the-nip cleaning approaches further require the use of complex heating roller designs that are capable of removing such wax while also providing heat and pressure to the toner image in the nip.

Similarly, in the '079 publication and the '205 publication, the toner image is allowed to cool below a glass transition temperature for the toner but while the wax is heated above the melting temperature of the wax. As an initial matter, these approaches are only useful for toners that have wax components with wax melting temperatures that are below a glass transition temperature of the toner. Further, these approaches risk damaging the toner image because they require the application of cleaning forces to the toner image when the temperature of the wax is above a melting temperature of the wax and the temperature of the underlying toner is at or close to the same elevated temperature.

What is needed in the art therefore are new methods, fusing systems and printers that enable a toner image to be formed using a toner with a wax while also managing the presence of any such wax on the toner image to eliminate density and gloss variations that without creating damaging the toner image.

SUMMARY OF THE INVENTION

Methods for operating a printer and wax management system are provided. In one aspect a method for operating a printer is provided with a toner image being formed on a receiver using a toner having a polymeric binder and a wax and with a contact surface being used to apply heat and pressure to heat the toner at least to a glass transition temperature for the toner and to heat the wax to at least an incorporated melting temperature to cause at least some of the wax to separate from the toner to reduce adhesion between the contact surface and the toner. The toner image is allowed to cool below a glass transition temperature of the toner to form a fused toner image having a viewing surface and allowing the wax to cool below the melting temperature for the wax so that after cooling the viewing surface has first portions with wax globules therein and second portions without wax globules. The viewing surface is wiped to move at least some of the wax from the wax globules in the first portions onto the second portions.

DETAILED DESCRIPTION OF THE DRAWINGS

FIG. 1is a system level illustration of a toner printer20. In the embodiment ofFIG. 1, toner printer20has a print engine22that arranges a toner24to form a toner image25. Toner image25can include any pattern of toner24and can be mapped according data representing text, graphics, photo, and other types of visual content, as well as patterns that are determined based upon desirable structural or functional arrangements of toner24.

Toner24can include one or more polymeric binder resins (toner resins) which can be optionally colored by one or more colorants. Colorants which can be pigments, dyes, and other limited wavelength light absorbers suitable for use in the practice of the present invention are disclosed, for example, in U.S. Reissue Pat. 31,072, and in U.S. Pat. Nos. 4,160,644; 4,416,965; 4,414,152; and 4,229,513. As the colorants, known colorants can be used. The colorants include, for example, carbon black, Aniline Blue, Calcoil Blue, Chrome Yellow, Ultramarine Blue, Du Pont Oil Red, Quinoline Yellow, Methylene Blue Chloride, Phthalocyanine Blue, Malachite Green Oxalate, Lamp Black, Rose Bengal, C.I. Pigment Red 48:1, C.I. Pigment Red 122, C.I. Pigment Red 57:1, C.I. Pigment Yellow 185, C.I. Pigment Yellow 155, C.I. Pigment Yellow 97, C.I. Pigment Yellow 12, C.I. Pigment Yellow 17, C.I. Pigment Blue 15:1, and C.I. Pigment Blue 15:3. Colorants can generally be employed in the range of from about 1 to about 90 weight percent on a total toner powder weight basis, and preferably in the range of about 2 to about 40 weight percent, more preferably from 4 to 30 weight percent, and most preferably 6 to 20 weight percent in the practice of this invention. When the colorant content is 4% or more and preferably 6% or more by weight, a sufficient coloring power can be obtained, and when it is 30% or less and more preferably 20% or less by weight, good transparency can be obtained. Mixtures of colorants can also be used. Colorants in any form such as dry powder, its aqueous or oil dispersions or wet cake can be used in the present invention. Colorant milled by any methods like media-mill or ball-mill can be used as well. The colorant may be incorporated, e.g., in the oil phase of limited coalescence process, or in the first aqueous phase of a multiple emulsion process as disclosed in U.S. Publication No. 2010/0021838.

The toner resin can be selected from a wide variety of materials including both natural and synthetic resins and modified natural resins as disclosed, for example, in U.S. Pat. Nos. 4,076,857; 3,938,992; 3,941,898; 5,057,392; 5,089,547; 5,102,765; 5,112,715; 5,147,747; 5,780,195 and the like, all incorporated herein by reference. Preferred resin or binder materials include polyesters.

In a toner printer20that uses an electrophotographic print engine22, toner24takes the form of toner particles that are charged and developed in the presence of an electrostatic latent image to convert the electrostatic latent image into a visible image. Toner particles without colorant can provide, for example, a protective layer on an image or that impart a tactile feel or other functionality to the printed image. Toner24has toner particles that include at least a polymeric binder resin and a wax at least some of which can separate from the toner particles to reduce adhesion between the toner particles and a heated fuser roller.

Toner particles can have any of a variety of ranges of median volume diameters, e.g. less than 8 μm, on the order of 10-15 μm, up to approximately 30 μm, or larger. When referring to particles of toner24, the toner size or diameter is defined in terms of the median volume weighted diameter as measured by conventional diameter measuring devices such as a Coulter Multisizer, sold by Coulter, Inc. The volume weighted diameter is the sum of the mass of each toner particle multiplied by the diameter of a spherical particle of equal mass and density, divided by the total particle mass. Toner24is also referred to in the art as marking particles or dry ink.

Typically receiver26takes the form of paper, film, fabric, metal bearing films, metal bearing fabrics, or metallic sheets, fibers or webs, and can be made from naturally occurring materials or artificial materials. However, receiver26can take any number of forms and can comprise, in general, any article or structure that can be moved relative to print engine22and processed as described herein.

In the embodiment ofFIG. 1, print engine22is used to deposit one or more patterns of toner24to form toner image25on receiver26. A toner image25formed from a single application of toner24can, for example, provide a monochrome image. A toner image25can also be formed by combining two or more toner images in registration. A toner image25that is formed in this manner can be used for a variety of purposes, the most common of which is to provide a toner image25that can include any of a wide range of colors. For example, a toner image25can include four toners24having subtractive primary colors, cyan, magenta, yellow, and black. Any of these four colors of toner24can be combined with toner24of one or more of the other colors at a particular location on receiver26to form any of a wide range of colors that are different than the colors of the individual toners24combined at that location. Similarly, in a five toner image various combinations of any of five differently colored toners24can be combined to form other colors on receiver26at various locations on receiver26.

In the embodiment ofFIG. 1print engine22is illustrated as having an optional arrangement of five printing modules40,42,44,46, and48, arranged along a length of receiver transport system28. Each printing module delivers a single application of toner24to a respective transfer subsystem50in accordance with a desired pattern as receiver26is moved by receiver transport system28. Receiver transport system28comprises a movable surface30that moves receiver26relative to printing modules40,42,44,46, and48. Surface30comprises an endless belt that is moved by motor36, that is supported by rollers38, and that is cleaned by a cleaning mechanism52.

In the embodiment ofFIGS. 1 and 2printing modules40,42,44,46, and48can each have a primary imaging member (not shown) on which a toner image25can be formed using an electrophotographic process. In one example of the electrophotographic process, the primary imaging member (not shown) is as a photoreceptor that is initially charged to a generally uniform difference of potential relative to a ground. An electrostatic latent image is formed by image-wise exposing the primary imaging member using known methods such as optical exposure, an LED array, or a laser scanner. The electrostatic latent image is developed into a visible image by bringing the primary imaging member into close proximity to a development station that contains a charged toner24. A development potential is applied at the development station that causes charged toner24to develop on the primary imaging member (not shown) according to the electrostatic latent image at each engine pixel location. This forms toner image25on primary the primary imaging member.

Each toner image25is transferred to a respective transfer subsystem50that presses toner image25against receiver26while subjecting toner image25to an electrostatic field that urges toner image25to transfer onto receiver26. In other embodiments, printer20can use a print engine22that forms a toner image25on receiver26in any other manner consistent with what is claimed herein.

After toner image25is transferred to receiver26, receiver26is moved by receiver transport system28to fuser60.FIG. 2shows one embodiment of fuser60. In this embodiment, fuser60comprises a fuser receiver transport system62having a transport belt64supported by a motorized roller66and a support roller68. In operation, motorized roller66responds to signals from a printer controller82to cause transport belt64to move receiver26and toner image25through a fusing nip70between a heated roller72and a pressure roller74. In this embodiment, pressure control system76applies a pressure that drives heated roller72and pressure roller74toward each other. Heated roller72is heated to a fusing temperature by a heater78which in this embodiment is an internal radiant type heater. Accordingly, when toner image25and receiver26enter nip70, toner image25is pressured into direct contact with heated roller72so that thermal energy from heated roller72is transferred directly into toner image25. Pressure control system76can comprise any mechanical structure that can provide an amount of pressure between heated roller72and pressure roller74when a toner image25and receiver26are situated therebetween. It will be appreciated that this type of fusing system is not critical and that in other embodiments, fuser60can comprise other known contact fusing systems including systems that use a heated belt to apply heat to a toner image during fusing.

In the embodiment ofFIG. 2, an optional actuator77is provided that can cooperate with an embodiment of pressure control system76such as a spring tensioning system (not illustrated) to control the amount of pressure applied between heated roller72and pressure roller74.

Returning toFIG. 1, printer controller82is in communication with and operates toner printer20based upon input signals from a user input system84, sensors86, a memory88and a communication system90. User input system84can comprise any form of transducer or other device capable of receiving an input from a user and converting this input into a form that can be used by printer controller82. For example, user input system84can comprise a touch screen input, a touch pad input, a 4-way switch, a 6-way switch, an 8-way switch, a stylus system, a trackball system, a joystick system, a voice recognition system, a gesture recognition system or other such systems. Sensors86can include contact, proximity, magnetic, or optical sensors and other sensors known in the art that can be used to detect conditions in toner printer20or in the environment-surrounding toner printer20and to convert this information into a form that can be used by printer controller82in governing toner image forming, transferring, fusing, or other functions. Memory88can comprise any form of conventionally known memory devices including but not limited to optical, magnetic or other movable media as well as semiconductor or other forms of electronic memory. Memory88can be fixed within toner printer20or removable from toner printer20at a port, memory card slot or other known means for temporarily connecting a memory88to an electronic device. Memory88can also be connected to toner printer20by way of a fixed data path or by way of communication system90.

Communication system90can comprise any form of circuit, system or transducer that can be used to send signals to or receive signals from memory88or external devices92that are separate from or separable from direct connection with printer controller82. Communication system90can connect to external devices92by way of a wired or wireless connection. In certain embodiments, communication system90can comprise any circuit that can communicate with one of external devices92using a wired connection such as a local area network, a point-to-point connection, or an Ethernet connection. In certain embodiments, communication system90can alternatively or in combination provide wireless communication circuits for communication with separate or separable devices using, for example, wireless telecommunication or wireless protocols such as those found in the Institute of Electronics and Electrical Engineers Standard 802.11 or any other known wireless communication systems. Such systems can be networked or point to point communication.

External devices92can comprise any type of electronic system that can generate signals bearing data that may be useful to printer controller82in operating toner printer20. For example and without limitation, one example of such external devices92can comprise what is known in the art as a digital front end (DFE), which is a computing device that can be used to provide an external source of a print order that has image data and, optionally, production data including printing information from which the manner in which the images are to be printed can be determined. A print order that is generated by such external devices92is received at communication system90which in turn provides appropriate signals that are received by printer controller82for use in determining operation of printer20.

Similarly, the print order or portions thereof including image and production data can be obtained from any other source that can provide such data to printer20in any other manner, including but not limited to memory88. Further, in certain embodiments image data and/or production data or certain aspects thereof can be generated from a source at printer20such as by use of user input system84and an output system94, such as a display, audio signal source or tactile signal generator or any other device that can be used by printer controller82to provide human perceptible signals for feedback, informational or other purposes.

To investigate the gloss and density variation problems that are associated with the use of toners having a wax component, the inventors have made test prints with a toner24having a polyester binder resin, wax, and colorant using a toner printer20of the electrophotographic type. Test prints were prepared for several different toners with test patches of a single toner type having 200% toner laydown and fused. The process speed was 10 ppm and the receiver on which the toner was provided was Utopia Gloss 270 gsm sold by Appleton Coated LLC, Combined Locks, Wis., USA.

FIG. 3shows an image of one example of a viewing surface130of a toner image25fused at a first temperature of 140 degrees Celsius and magnified at 2000×, whileFIG. 4shows an image of one example of a viewing surface of a toner image fused at the first temperature of 140 degrees Celsius at a magnification of 10,000×. Through these images it has been discovered that wax150takes the form of wax globules152on viewing surface130of a fused toner image132and many of which have indistinct or irregular but generally rounded surfaces above viewing surface130.

Similarly, test prints have been made with a toner24having a wax and these test prints have been fused at a higher fusing temperature than the test prints shown inFIGS. 3 and 4. Images of these test prints have also been captured at high magnification and are shown inFIGS. 5 and 6. In particular,FIG. 5shows a 2000× magnified image of one example of a viewing surface130of a toner image25that is fused at a temperature of 160 degrees Celsius whileFIG. 6shows a 10000× magnified image of a viewing surface130of a toner image25that is also fused at a temperature of 160 degrees Celsius. Here too wax150is present in the form of wax globules152.

FIG. 7is a cross-section view of one conceptual model of a toner print20generated using toner24with a wax after a fusing process.FIG. 7is not to scale but instead is provided to help to illustrate light transmission and reflection of a fused toner image132with a viewing surface130having first portions146with one or more wax globules152and second portions148that do not have wax globules152. Accordingly, relative sizes of, shapes or directions of structures or light schematically illustrated inFIG. 7have been selected to support the following discussion points and actual conditions can vary from those indicated here. It will be understood that the following depiction is not intended as an exhaustive analysis of all effects that a fused toner image and wax globule may have on light but rather to provide a general overview of some readily apparent potential effects.

As is shown inFIG. 7, a fused toner print120has a receiver26with a fused toner image132. Fused toner image132has a lower surface128that is adhesively bonded to receiver26during fusing and a viewing surface130that presents a toner/air boundary. When light134is applied to viewing surface130, one portion of light134is reflected in a specular manner by viewing surface130to form a toner gloss reflection136and another portion of light134passes through toner image25as light138. Light138strikes receiver26and reflects according to the reflectance characteristics of receiver26. Where receiver26is highly reflective, light138will reflect in a more specular manner as is illustrated here, to form receiver reflected light140however, where receiver26reflects less light in a specular manner, light138can be diffusely reflected and a smaller portion of light138will reflect as receiver reflected light140that travels along the direction of specular reflected light.

To the extent that fused toner image132has one or more toners with a colorant therein such as a pigment or dye, certain wavelengths of light138and receiver reflected light140will be absorbed in part or in whole by these colorant(s). Toner combinations are selected for use in making a toner image such that when fused toner image132is exposed to light, fused toner image132absorbs particular wavelengths to cause light142that emerges from viewing surface130to have a desired color content.

As is also shown inFIG. 7, light142that emerges from viewing surface130travels in a direction that is determined by the angle of incidence of receiver reflected light140with viewing surface130, the index of refraction of the toner image25and the index of refraction of air.

As is also shown inFIG. 7, a light160that is parallel to light134but incident on a portion of a viewing surface130that has a wax globule152thereon is treated differently from light134that is incident on viewing surface130. In this regard, wax globule152has an upper boundary154between air and wax150forming wax globule152and a lower boundary156between wax globule152and viewing surface130. As is further shown inFIG. 7, upper boundary154has a radius of curvature relative to what is illustrated here for the purposes of discussion as a generally flat viewing surface130.

Accordingly, when a light160confronts upper boundary154a first portion of light160is reflected by upper boundary154in a generally specular manner at an angle determined by a tangent of the curvature of upper boundary154to form a wax gloss reflection162. Wax gloss reflection162is reflected in a direction that is different from the direction of toner gloss reflection136. This creates a variation in the apparent gloss of fused toner image132in the region of the wax globule152.

A second portion164of light160passes into wax globule152at upper boundary154and travels through wax globule152at an angle that is determined by the index of refraction of air proximate and the index of refraction of wax globule152as well as the angle of incidence of light160. To the extent that wax150is not colorless and to the extent that wax150may have non-uniform wax densities or porosity or other materials therein, a portion of light164will be absorbed by wax globule152. Further, wax globule152can cause a portion of light164to be diffused within wax globule152such as by reflection, local illumination or absorption and reemission or other known optical effects. Such effects cause light166to appear to reflect or to be emitted from within wax globule152. Light166can have the effect of reducing the apparent density of the portion of fused toner image132under wax globule152.

The remaining portion of light164then crosses lower boundary156and travels as light168at an angle that is determined by the angle of incidence of light168, the index of refraction of wax150and the index of refraction of the toner forming fused toner image132. As is also illustrated here there can be a secondary toner gloss reflection169when light164reaches viewing surface130. However, secondary gloss reflection169travels along a different path than toner gloss reflection136.

Light168then travels through fused toner image132, is partially absorbed by any colorants in fused toner image132and is then reflected by receiver26. The reflection can occur in a more specular manner when receiver26is more reflective and in a more diffuse manner when receiver26is less reflective. Here a generally specular reflection is illustrated. A portion170of light168is then reflected by receiver26and passes through fused toner image132a second time. Again, to the extent that there is any colorant in fused toner image132, a portion of light170is also absorbed so that a smaller portion of light170passes through viewing surface130of fused toner image132and back into wax globule152as light172. Light172passes through wax globule152at an angle that is determined according to the angle of incidence of light172at the lower boundary156, the index of refraction of wax150, and the index of refraction of fused toner image132.

To the extent that the material forming wax globule152absorbs light in a non-uniform manner and to the extent that wax globule152may have non-uniform wax densities or porosity or other materials therein, a portion of secondary gloss reflection169and light172will be absorbed by wax globule152. Further, to the extent that wax globule152can cause a portion of secondary gloss reflection169and light172to be reflected or reemitted within wax globule152such as by reflection, local illumination, absorption and reemission, or other known optical effects a portion of secondary gloss reflection169will be reemitted as light173and a portion of light172as light174both apparently from within wax globule152.

Light174travels at an angle that is determined by the angle of incidence of light172, the index of refraction of wax150and the index of refraction of air or whatever medium surrounds wax globule152. It will be noted that the angle of incidence is generally determined according to a tangent taken at the upper boundary154of wax globule152. Similarly, any remaining portion of secondary gloss reflection169passes through upper boundary154to become light171that travels at an angle that is generally determined by the angle of incidence of secondary gloss reflection169, the index of refraction of wax150and the index of refraction of air or whatever medium surrounds wax globule152. Here too, the angle of incidence is determined according to a tangent taken at upper boundary154of wax globule152.

It will be appreciated from this that the presence of wax globule152creates a number of effects on light that is incident on fused toner image132that can negatively impact the gloss of a fused toner image132. These include at least providing specular reflection of light160as wax gloss reflection162that is directed along a path that is not parallel to toner gloss reflection136, providing a secondary toner gloss reflection169that creates a light171that is also not parallel to toner gloss reflection136. Additionally, the wax itself can have a different reflectance than toner24used to form fused toner image132. These effects create variations in the gloss of viewing surface130of fused toner image132between the first portions146and second portions148of fused toner image132that generally reduce the apparent gloss of the fused toner print120.

Additionally, it will be appreciated that the presence of wax globule152can also negatively impact image densities in fused toner print120. In particular, wax globules152create uneven illumination of fused toner image132. Wax globules152can also create image independent low density areas where there is light emission from the wax globules152. Wax globules152also reduce the apparent sharpness of fused toner image132by causing localized variations in the path of travel of light through wax globule152.

It will also be appreciated that these effects are exacerbated by the irregular, indistinct, or blob-like form of wax globules152. In particular, the form of wax globules152significantly influences the direction of gloss producing reflections, and further alters a path of travel of light that passes through wax globule152to cause secondary gloss reflections to occur in directions that are inconsistent with a direction of toner gloss reflections. Further the form of wax globules152can provide areas within a single wax globule152where light that travels through wax globule152is reflected differently or has a greater opportunity for deflection, internal reflection or reemission than light that strikes other portions of wax globule152. This can enhance the above described effects and therefore make the gloss and density variations caused by such effects more evident.

However, the fundamental challenges associated with efforts to fully remove wax150from a fused toner image132remain. Specifically, while improvements in gloss and in image density sought after by the prior art are desired, it is unacceptable to attempt to remove wax in a way that risks damaging viewing surface130of fused toner image132.

Accordingly, toner printer20ofFIG. 1is shown having a wax management system100that is positioned to accept a fused toner image132and receiver26from fuser60and to process the fused toner image132to manage the wax globules152thereon to improve the gloss and optionally the image density of fused toner image132. As is shown inFIG. 1, a print transfer system103is used to transfer fused toner print120from fuser60to wax management system100. Print transfer system103, wax management system100and controller82operate to provide controlled delivery of fused toner print120to wax management system100. As is also shown inFIG. 1, an optional cooling system105is provided that can apply an air flow to cool fused toner print120before wax management is performed. Cooling system105can supply chilled air or a flow of ambient air. In other embodiments cooling system105can be integrated with fuser60such as where a belt type fuser is used that maintains contact with a fused toner image132in order to ferrotype the fused toner image132. Similarly print transfer system103can be integrated into either of fuser60or wax management system100. Print transfer system103and optional cooling system105are shown connected to controller82allowing controller82to influence the operation of these systems.

FIG. 8shows one embodiment of a method for operating a toner printer20having a wax management system100. In this embodiment, a toner image25is provided on receiver26using a toner24having a polymeric binder and a wax150(step200). Wax150separates from the particles of toner24when they are heated to an incorporated melting temperature for incorporated wax150. Wax150acts as a release agent to limit the extent to which an adhesive bond can form between particles of toner24and a contact surface such as heated roller72ofFIG. 2during contact fusing.

A useful consideration in selecting wax150is the melting temperature of wax150. In certain embodiments, wax150can have a melting point above the glass transition temperature of toner24. It is generally preferred to have the melting point of wax150above the toner glass transition temperature but below the fusing temperature since this will allow the toner to enter a glassy state before the wax melts. This allows wax150to melt upon contact with a heated contact surface such as heated roller72to form slip layer that reduces adhesion between toner24and the contact surface. The thermal characteristics of toner24, such as a glass transition temperature of toner24and an incorporated wax melting point of a wax150that is incorporated into a toner24, can be determined by conventional methods, e.g., differential scanning calorimetry (DSC). Here, the endothermic peak temperature is defined as a melting point of a wax. If a wax has multiple peaks, the melting point is the lower peak temperature.

A wax150with a very high melting point can require higher fusing temperatures and can hinder the speed at which toner image25will be fused. A wax150having a very low melting point can limit the durability of the post fused image, particularly where a toner24having such a low melting point wax is fused at a high fusing temperature. In one embodiment wax150has a melting point temperature that is 5 degrees Celsius greater than a glass transition temperature of toner24. In other embodiments, wax150can have a melting point that is less than 100 degrees Celsius.

Examples of such waxes include polyolefins such as polyethylene wax and polypropylene wax, and long chain hydrocarbon waxes such as paraffin wax. Another class of waxes is carbonyl group containing waxes which can include long-chain ester waxes. The waxes WE-3 and WE-8 made by NOF Corporation of Japan are long-chain ester waxes made from long-chain fatty acids and alcohol. These waxes are preferred in certain embodiments because they have a narrow melting range and have melting points that are above typical toner glass transition temperatures of the binder resins in many conventional toners and further have melting points that are less than 100 degrees Celsius. For example, WE-3 has an unincorporated single melting point peak of 70.8 degrees Celsius while WE-8 has two endothermic peaks of 71.8 and 80.2 degrees Celsius for an unincorporated melting point of 71.8 degrees Celsius.

In certain embodiments, the glass transition temperature of the binder polymer can be between about 40 degrees Celsius and 80 degrees Celsius. In other embodiments, the glass transition temperature of the binder resin more typically between about 45 degrees Celsius and 70 degrees Celsius. In still other embodiments, the glass transition temperature of the binder resin can be between about between 50 degrees Celsius and 65 degrees Celsius.

In the embodiment ofFIG. 8, printer controller82receives a print order and causes print engine22to generate a toner image25having a pattern of toner24based upon the print order and causes toner image25to be transferred to receiver26. Printer controller82then causes receiver transport system28to carry toner image25and receiver26to a fuser60.

A contact surface is used to apply heat and pressure to heat toner24forming toner image25at least to a glass transition temperature of the toner24and to heat wax150at least to an incorporated melting temperature of incorporated wax150(step202). This causes at least some of wax150to separate from toner24to reduce adhesion between heated roller72and toner24. In toner printer20, fusing is done can be done as is described above using fuser60where the contact surface comprises heated roller72. However in other embodiments, such a contact surface can take the form of a heated belt or platen or any other heated surface that directly contacts a toner image25during fusing.

Toner image25is allowed to cool below a glass transition temperature of toner24to form a fused toner image132having a viewing surface130and wax150is allowed to cool below a melting point of the wax150to form wax globules152(step204) so that after cooling viewing surface130has first portions146with wax globules152and second portions148without wax globules152. As is also discussed above, the presence of wax globules152causes first portions146and second portions148to reflect and transmit incident light in different ways and to have a first gloss and a second gloss, respectively that are different. As is discussed above, wax globules152can also cause density variations. In certain embodiments, controller82operates fuser60, transport103, and wax management system100so that wax management is performed after the toner image and the wax have been allowed to cool below the glass transition temperature of the toner and the melting temperature for wax150. This can be done in a variety of ways and the exact manner of cooling is not critical. In one embodiment, the distance between fuser60and wax management system100and the rate of transport between fuser60and wax management system100can be selected to allow cooling when controller82causes transport to occur. In other embodiments, controller82can drive cooling system105and transport system103in ways that allow the cooling to occur. Other embodiments are possible.

FIG. 9presents a conceptual illustration of a fused toner image132on a receiver26having a viewing surface130with wax globules152thereon.FIG. 9is not to scale. As is shown inFIG. 9, a fused toner image132has a viewing surface130with wax globules152A,152B and152C arranged thereon in first portions146among second portions148of viewing surface130. As is shown inFIG. 9viewing surface130is not flat but varies within a range of heights220between a lower height222relative to receiver26and an upper height224relative to receiver26. As will be appreciated fromFIG. 9, such variations in height can also create gloss reducing variations on viewing surface130. Wax globules152A,152B and152C also have variable globule heights relative to viewing surface130and that can combine with the variations on viewing surface130to substantially increase the extent of total variations and therefore substantially reduce gloss.

FIG. 10illustrates, conceptually, the range of heights of wax globules152A,152B and152C relative a baseline130representing an average height of the viewing surface130on which wax globules152A,152B and152C rest. As can be seen here, wax globules152A,152B and152C have a range234of heights that are between a lower height236associated with wax globule152B and a higher height238associated with wax globule152C.

InFIGS. 9 and 10, wax globules152A,152B and152C are shown having in a generalized fashion having substantially domelike shapes however as is apparent fromFIGS. 3-6wax globules152generally have an irregular, indistinct or other generally blob like shape. InFIG. 10each wax globule152A,152B, and152C is shown associated with a respective one of circles240A,240B and240C. Circles240A,240B and240C are each taken at a best fit to the general curvature of wax globules152A,152B and152C and each has one of an associated first radius242A,242B and242C. The radii242A,242B and242C each generally correlate to an extent of curvature of upper boundaries154A,154B and154C of wax globules152A,152B and152C. It will be appreciated that the shape and extent of projection of upper boundaries154A,154B and154B of wax globules152A,152B and152C can have a significant impact on the extent of any variations in gloss or density caused by the presence of wax150on viewing surface130.

This is particularly true where, as shown for wax globules152A and152C inFIG. 9, wax globules152A and152C add height to portions of viewing surface130that is already higher relative to receiver26than other portions of viewing surface130as measured relative to receiver26. This is also particularly true where upper boundaries154A,154B and154C have shapes that are relatively irregular as opposed to the regular type shapes illustrated inFIGS. 9 and 10.

Viewing surface130of fused toner image132is then wiped to move at least some of wax150from wax globules152in first portions146to second portions148(step206). This can have the effect of reducing the extent to which wax150is organized into globules. This can also yield gloss and density improvements. Further, this can reduce the extent of differences between the gloss of first portions146and the gloss of second portions148.

FIG. 11shows one embodiment of a wax management system100that can be used for this purpose. In this embodiment wax management system100comprises a wiping system250having a wiping surface254that is wiped to move wax150.

In this embodiment wiping system250comprises a wiping surface support252that supports a woven and compressible wiping surface254by way of an optional resilient intermediary256such as resiliently deformable foam. Wiping surface254can take any of a variety of forms and can comprise, for example, a paper, a fabric, a woven material, a polyester sheet or a fibrous surface or a polymeric or other form of material which itself can be compressible. Wiping surface254can be used repeatedly or cleaned or replaced as necessary. In the embodiment that is illustrated inFIG. 11, wiping surface254comprises a KIMTECH Science RTM Kimwipe sold by Kimberly-Clark, Dallas, Tex., USA that is mounting around wiping surface support252between a first mounting258and a second mounting260. Optionally, first mounting258and second mounting260can comprise respectively a source and a take up that allow different portions of a wiping surface254to be rotated past a cleaning position on wiping member so that wax or any contaminants in wax globules152A,152B or152C or any environmental contaminants such as dust, dirt, magnetic carrier, toner, metallic particles or wiping surface254do not have an opportunity to accumulate to the point where they can damage viewing surface130.

In the embodiment ofFIG. 11, wiping surface support252is shown optionally joined by a linkage262to a wiping actuator system264having an actuator266and a wiping rail268. During wiping, actuator266moves along wiping rail286to move wiping surface support252and wiping surface254in a first wiping direction269. Optionally, wiping can be done more than once and can be done along a plurality of different wiping angles relative to fused toner image132. In one embodiment, this can be done by providing a wax management system100that has multiple combinations of a wiping surface support252, a wiping surface254and a wiping actuator system264arrange to wipe from different directions during a single pass of the toner image25through wax management system100. In another embodiment, this can be accomplished by positioning fused toner print120in wax management system100for wiping multiple times with rotation of fused toner image132and receiver26between wiping operation.

As performed here the wiping moves wax150from wax globules1520in first portions146onto second portions148. This reduces the height or increases the radius of curvature of wax globules152in order to reduce the optical effects caused by wax globules152. This improves the gloss of fused toner image132and makes the gloss response of first portions146and second portions148more consistent. Additionally, during wiping a portion of wax150moved from a wax globule may remain on wiping surface254and may be disposed in other ways. However, removal of all or substantially all of wax150sufficient to clean viewing surface130is not required. Accordingly, wiping system250need not apply sufficient force against viewing surface130to clean wax150from viewing surface130. For example, wiping surface254can be supported by a resilient intermediary256that can be resiliently compressed so that wiping surface254will apply a limited amount of force during wiping that is insufficient to damage viewing surface130. The resilient compressibility of the resilient intermediary256can be such that a wax globule152can cause wiping surface254to conform at least in part to the shape of wax globule152. Where this occurs, the wiping force can be sufficient to remove only a part of wax150from a wax globule152and to reposition wax150from first portions146on which wax globule152rests to the second portions148of viewing surface130.

The inventors have simulated the effects of a single pass multi direction wiping process manually. In this regard the test prints giving rise to the toner images shown inFIGS. 3-6have were manually wiped at two different wiping angles relative to the viewing surface130. In the test cases, this wiping has been done at wiping angles that are 90 degrees apart from each other. Gloss measurements were made before and after wiping. The results that were achieved are shown in Table I.

In examples 1 and 2, a first type of binder designated as BR1was used. BR1comprises linear polyesters of bisphenol A and terephthalic acid. In examples 3 and 4 a second type of binder designated BR2was used that comprised a blend of linear, cross-linked and branched polyesters of bisphenol A and terephthalic acid. The 15:3 Phthalocyanine Blue colorant levels associated with the BR1and BR2were 3.9 and 4.4 weight percent respectively.

All gloss measurements shown in Table I are G-60 gloss measurements determined using a Gardener Micro-TRI-Gloss 20-60-85 Glossmeter available from BYK, Gardner River Park, Md., USA. Toner glass transition temperature and incorporated wax melting point temperature were determined from a second heating cycle of an 8 to 12 mg. toner sample using a differential scanning calorimeter (Q100 manufactured by IA Instruments of New Castle Del.). The toner sample was treated by raising its temperature to 150 degrees Celsius at a heating rate of 10 degrees Celsius/min. cooling the sample at a cooling rate of 20 degrees Celsius/min. to 25 degrees Celsius and thereafter heating the sample at a heating rate of 10 degrees Celsius/min. to 150 degrees Celsius.

These results show that there has been a substantial increase in gloss performance using these wiping techniques. Further, it will be noted that, although not measured, a density increase in the wiped patches was also observed.

The effects of such wiping are further illustrated inFIGS. 12-14.FIG. 12shows post wiping images of a viewing surface130having a toner image25fused at a first temperature of 140 degrees Celsius and magnified at 2000× whileFIG. 13shows a post wiping view of one example of a viewing surface130of a toner image fused at temperature of 140 degrees Celsius at a magnification of 10,000×. Wax globules152are difficult to discern even at this high magnification.

FIG. 14shows a 10000× magnified image of a post-wiping viewing surface130of a fused toner image132that has been fused at a temperature of 160 degrees Celsius. Here too wax150in the form of wax globules152is difficult to detect.

Although it is difficult to see any wax150in the form of wax globules152inFIGS. 12,13, and14, further analysis of the test patches used in this analysis reveals that wax150is still present on viewing surface130of these fused toner image132. Specifically, the toner images that have exhibited improved gloss after wiping were subsequently subjected to a ball point pen writeability test. While writeability improved, indicating that some of the wax was removed, writeability was still compromised compared to non-wax containing toner images indicating the continued presence of wax in quantities sufficient to interfere with writeability, but not in the globular form. This indicates that gloss improvements and density improvements are possible without fully cleaning the wax from the surface of the toner image. With this understanding, it is clear fromFIGS. 12-14that at a minimum as a consequence of the wiping process, the relief differentials crated by any pattern of wax150is now difficult to distinguish from normal variations in viewing surface and therefore the effects of such variations are difficult to distinguish making these effects essentially invisible.

In this regard,FIGS. 15 and 16, show respectively, a conceptual illustration of a fused toner image132on a receiver26having a viewing surface130with wax globules152thereon after fusing and wax management and, conceptually, a range of heights of wax globules152relative to a baseline representing viewing surface130, after wax management. As is shown inFIGS. 15 and 16, there is a movement of wax150from wax globules152from first portions146at least in part to second portions148. This significantly increases radii242A,242B and242C that correlate to upper boundaries154A,154B and154C of wax globules152A,152B and152C as compared to the radii242A,242B and242C illustrated inFIGS. 9 and 10before wiping. As can be seen inFIGS. 5 and 9, viewing surface130and wax globules152on viewing surface130have a first range of total heights225above receiver26after fusing and have a second range225′ of total heights above receiver26after the wiping that is at least in part less than the first range225of heights. As can be seen inFIGS. 10 and 16wax globules152on viewing surface130have a first range of globule heights234above viewing surface130after fusing that is at least in part greater than a second range234of wax globule heights above viewing surface130after wiping.

These conditions improve the gloss of fused toner image caused by wax globules152at least in part by reducing the extent of any relief patterns caused by wax globules152and optionally can be established so that that after cooling the fused toner image132has a viewing surface130with heights that vary within a range of viewing surface heights and wherein after wiping viewing surface130and wax150on viewing surface130have a range of total heights that is within the range of variations of viewing surface heights so that any additional height provided by the wax150on viewing surface130does not increase the extent of any gloss variations beyond the variations caused by variations in the height of viewing surface130.

This reduces gloss variations by diminishing the scattering of light caused by different angles of specular reflection created by upper boundaries154A,154B and154C of wax globules152A,152B and152C and further reduces the extent to which a beam of light must travel through wax in a wax globule thereby reducing the opportunity for the light to be reflected or deflected by materials in the wax thus improving gloss. Further to the extent that such gloss variations caused by wax150on viewing surface130continue to exist after wiping, these effects are more evenly distributed across the viewing surface130and therefore create less of a variation. For similar reasons, density variations cause by wax150and in particular by wax globules152will be reduced.

Further it will be appreciated that the overall extent of height variations along viewing surface130can be reduced in this manner in some instances. As is shown inFIG. 15the portion of viewing surface130that is covered in wax150expands while the uncovered portion contracts after wiping.

FIG. 17illustrates another embodiment of a wax management system100. In this embodiment, wiping system250comprises a resilient wiper blade270having a shallow working angle between a wiping surface254of wiper blade270and viewing surface130. Such a shallow working angle, in the range of 2 to 40 degrees is not particularly effective at removal of wax150and will move at least some of the wax150from wax globules152in first portions146to second portions148. This can also be used in certain embodiments to help to ensure that wherever possible some wax150from wax globules152A,152B and152C is maintained between wiper blade270and viewing surface130so as to minimize direct contact between wiper blade270and viewing surface130and can act, as a friction reducing lubricant between wiper blade270and viewing surface130during wiping. This lubrication effect can also arise in other embodiments. As is also shown in this embodiment, it is not necessary that a wiping system250have a wiping surface254that is movable relative to a viewing surface130of a fused toner image132on a fused toner print120and a system for moving wiping surface254. Instead as is shown in this embodiment, a wax management system100can have a print positioning apparatus310for moving a fused toner print120during wiping. For example, as is shown inFIG. 18, print positioning apparatus310can be moved to provide a support278such as a belt or roller system that an actuator279moves to advance fused toner print120past wiping surface254to wipe viewing surface130.

In other embodiments wax management system100can take other forms. For example, as is shown inFIG. 18, wax management system100has a roller280with a wiping surface254. Roller280is supported by and is rotatable around a wiping surface support252. Wiping surface support252in turn is optionally joined by a linkage262to an actuator system264. Actuator system264has an actuator and a wiping rail268. During wiping, actuator system264moves along wiping rail268to move wiping surface support252and therefore roller280and wiping surface254along first wiping direction269. In this embodiment, support252includes a rotation control system282that controls rotation of roller280about support252. In the embodiment that is illustrated inFIG. 18, rotation control system282has an actuator such as a motor that can control or influence a rate of rotation of roller280during the wiping process. The rate of rotation of roller280can be less than a relative rate of movement between roller280and viewing surface130to encourage wax movement. In other embodiments of this type, roller280can be made to rotate as a product of contact with viewing surface130and in such an embodiment, rotation control system282can comprise any form of transmission, linkage or braking system that limits a rate of rotation of roller280such that roller280rotates at a rate that is less than a rate of movement of roller280across viewing surface130during wiping. It will be appreciated that, in order to protect against scraping viewing surface130, it will be beneficial in certain embodiments to provide the movement of wax150without creating a risk of unnecessary friction between wiping surface254and viewing surface130.

In other embodiments, wiping surface254can be a web such as is described above that is supported by roller280.

In one embodiment the surface of roller280is elastomeric and is sufficiently resiliently compressible such that a wax globule152can cause a wiping surface254to conform at least in part to the shape of wax globule152. Where this occurs, the force applied by the roller280can be sufficient to move only a part of any wax150forming wax globules152from first portions146to second portions148of viewing surface130.

Wax management system100can be integrated into a printer20or can act as a standalone device that receives toner prints from printer20and that manages the wax thereon in line with printer20as a standalone device that can be used as needed. In this regard, printer20can have a wax management system100that is integral to toner printer20or wax management system100can be separable from toner printer20such as a modular attachment. In still another embodiment, printer20can be use with a stand alone wax management system100that can be used to manage wax150on fused toner prints made by toner printer20but that can be used in cooperation with printer20or without any connection with toner printer20.

It will be appreciated that such a standalone embodiment can be used to perform wax management on fused toner prints120on an as needed basis and on fused toner prints120that have been printed hours, days or months before being submitted for wax management. Further, it will be appreciated that such stand alone embodiments of wax management system100can manage wax150on a viewing surface130of a fused toner image132without requiring that wax150be in a liquefied state. This allows such stand alone embodiments to be used without requiring that fused toner image132be at an elevated temperature required to heat wax150above a melting temperature for wax150.

FIG. 19illustrates another example of such a standalone embodiment of a wax management system100in greater detail. As is shown inFIG. 19, in this embodiment, wax management system100has a print positioning system300that is generally contained or supported by a housing301. Print positioning system300has an input302that receives a fused toner print120from outside of housing301. Fused toner print120has a fused toner image132with a viewing surface130that has first portions146with wax globules152and second portions148without wax globules152.

In this embodiment, print positioning system300also has a print positioning apparatus310that is used to position fused toner print120for wiping by a wiping system250. Here, print positioning apparatus310comprises a carrier surface312that carries fused toner print120from input302past an arrangement of guides314and316that contact sides of fused toner print120to position fused toner print120for wiping. In the embodiment illustrated carrier surface312comprises a slide surface that uses gravity to draw fused toner print120from input302to a wiping surface318where fused toner print120is positioned for wiping by a wiping system250. However, in other embodiments, carrier surface312can be, for example, an endless belt, a powered arrangement of rollers, or any other known conveyance systems that can cause a fused toner print120to move from one position to another.

As is also shown inFIG. 19, in this embodiment wax management system100has a wax management system controller330that communicates with a presence sensor304to sense the presence of fused toner print120at input302and that further communicates with one or more actuators306that control print positioning apparatus310, in order to ensure that a fused toner print120is positioned for wax management by wiping system250and in order to ensure that wiping system250successfully wipes fused toner print120. Presence sensor304can comprise any known form of sensor that can be used to detect signals from which the presence or absence of fused toner print120can be determined.

As is also shown inFIG. 19, wax management system100can further comprise an optional cooling system320. Cooling system320cools fused toner print120before wiping. Cooling system320can comprise a contact cooling system, a forced air cooling system or other conventional forms of cooling systems.

A first temperature sensor system308and a second temperature sensor system322are shown inFIG. 19. First temperature sensor system308is positioned to sense the temperature of a fused toner print120at input302while second temperature sensor system322is shown positioned to sense a temperature of a fused toner print120that is positioned for wiping by wiping system250. Temperature sensor systems308and322can comprise infra red sensitive devices such as an optical switch, photosensor or imager that can detect a temperature of a fused toner print120for use in controlling cooling system320or wiping system250. Any other form of sensor that can detect a temperature or any other condition indicative of the temperature of a fused toner print can also be used.

In the embodiment ofFIG. 19, presence sensor304detects the presence of a fused toner print120and sends a signal to wax management system controller330from which wax management system controller330can determine that fused toner print120is in input302.

Wax management system controller330then determines when the fused toner image120is at a temperature where fused toner image132is below a glass transition temperature of the toner24forming fused toner image132and wax150is below a melting temperature for wax150. In this embodiment, this is done using first temperature sensing system308positioned in input302. When wax management system controller330determines that fused toner print120is not at an appropriate temperature, wiping of the fused toner print120can be delayed to allow cooling. Additionally, optional cooling system320can be activated to accelerate such cooling.

After it is determined that a fused toner print120is at a temperature where fused toner image132is below a glass transition temperature of the toner24and the wax150is below a melting temperature for wax150, wax management system controller330can cause print positioning apparatus310to position fused toner print120for wiping. Wax management system controller330then causes print positioning apparatus310to move cooled fused toner print120to wiping system250. Once fused toner print120is positioned relative to wiping system250, wax management system controller330causes wiping system250to cause wiping surface254to wipe viewing surface130to move at least some of wax150from wax globules152in first portion146onto second portion148.

Alternatively, wax management system controller330can cause print positioning apparatus310to move fused toner print120to wiping system250and can cause wiping system250to delay wiping until second temperature sensor system322sends signals to wax management system controller330from which wax management system controller330can determine that fused toner image132is below a glass transition temperature of toner24and wax150is below a melting temperature for wax150. In this alternative embodiment, second temperature sensing system322can be used to monitor the temperature of any fused toner print120at wiping system250.

It will be appreciated by those of skill in the art that first temperature sensor system308and second temperature sensor system322can be used in various combinations to provide signals to wax management controller332to allow wax management system controller330to ensure that wax management is not performed until the toner forming toner image24is below a glass transition temperature of toner24and wax150is below a melting temperature for wax150.

In other embodiments, other methods can be used to ensure that wiping is performed when fused toner image132is below a glass transition temperature of the toner24and the wax150is below a melting temperature for wax150, such as by providing a cooling system320that is capable of cooling any fused toner print to the desired conditions for wiping, or by transporting the fused toner print120such that sufficient time has been allowed for the fused toner print120to reach a condition where fused toner image132is below a glass transition temperature of the toner24and the wax150is below a melting temperature for wax150.

It will also be understood that wax management system controller330can determine that fused toner image132is below a glass transition temperature of toner24and wax150is below a melting temperature for wax150in ways that do not require temperature sensing. For example, wax management system controller330can receive information from which wax management system controller330can determine that conditions indicate that cooling is sufficient. Examples of such information include but are not limited to data from which an amount of time since fusing can be determined, data from which an elapsed travel distance since fusing, can be determined or data that indicates that cooling has been performed by toner printer20before transfer to wax management system100.

In the embodiment ofFIG. 19, wiping system is shown having a wiping surface254takes the form of a wiper blade that is moved along a track system253by an actuator257. It will be appreciated that any embodiment of a wiping system250described herein can be used with stand alone embodiment of wax management system100to manage wax150.

As is further shown in this embodiment, wax management system100has an optional gloss sensor system340with one or more light emitters342that apply a light344to viewing surface130and that has one or more light sensors346that are positioned to detect the extent to which viewing surface130reflects light344as a specular reflection348. The amount of light sensed by light sensors346is then used by wax management system controller330or by a local gloss sensor controller (not shown) to determine an extent of the gloss of portions of viewing surface130. It will be appreciated that gloss sensor system340can take the form of any other device that can be used to measure the gloss of a surface.

In one embodiment, a wax management system controller330can cooperate with cooling system320, second temperature sensor system322, gloss sensor system340and wiping system250so that wax management system controller330can control the wiping process based upon signals from the gloss sensor system340, such as by determining a number of times that wiping is performed or determining a combination of different directions of the wiping based upon signals from gloss sensor system340.

It will be appreciated that any other embodiment of wax management system100including those that are incorporated into a toner printer20or those that are incorporated into modules that are intended for use with but that are separable from toner printer20can also incorporate a cooling system320, a wax management system controller330or a gloss sensor system340and/or any other features, methods or aspects of the embodiment ofFIG. 19.

It will also be appreciated that where wax management system100is part of, is joined to or is otherwise in communication with a toner printer20any functions ascribed herein as being performed by wax management system controller330can be performed by printer controller82.