System and method for printing a document having texture

Abstract

The invention is entitled "System and method for printing a document having a texture". The aqueous inkjet printer also ejects droplets of a UV material on the aqueous ink image, and exposes the aqueous ink image and the UV material to UV radiation before passing the aqueous ink image and the UV material through a thermal dryer. The exposure to UV radiation fixes the UV material to the aqueous ink image and the underlying substrate, and the thermal dryer fixes the aqueous ink image to the substrate while releasing free radicals from the UV material. Thus, the printer produces a textured print without free radicals that could irritate the skin or produce a noxious odor.

Description

Technical Field

[0001] The present disclosure relates to inkjet printers, and more particularly, to printing textures on documents with such printers. Background Art

[0002] Inkjet imaging devices, such as inkjet printers, are well known. These printers eject liquid ink from a printhead to form an image on an image receiving surface. The printhead includes a plurality of inkjet ports arranged in some type of array. Each inkjet port has a thermal or piezoelectric actuator coupled to a printhead controller. The printhead controller generates a firing signal corresponding to digital data for an image. An actuator in the printhead responds to the firing signal by ejecting ink droplets onto an image receiving member, and forms an ink image corresponding to the digital image used to generate the firing signal.

[0003] For some forms of documents, textured printing is preferred. For example, business cards, posters, and invitations are often printed with raised or coated characters or graphics. Raised characters and graphics, as well as the gloss and variable reflections that may be created by textured printing, are often perceived as more aesthetically pleasing than non-textured printing.

[0004] Aqueous inkjet printers use water-based or solvent-based inks, in which pigments or other colorants are suspended or in solution. These inks have the advantage of being non-toxic and generally odorless. In addition, the vigor of the colors produced by aqueous inks makes them useful for fine art printing. Once aqueous inks are sprayed onto the image receiving surface by a print head, the water or solvent is evaporated to stabilize the ink image on the image receiving surface. When aqueous inks are sprayed directly onto a medium, the aqueous inks tend to soak into the medium, and when the medium is porous, such as paper, the water in the ink changes the physical properties of the medium. Because the spread of ink droplets hitting the medium is a function of the surface properties and porosity of the medium, the print quality may be inconsistent. In addition, because aqueous inks tend to be absorbed by some media, they are not conducive to building layers that can be used for textured printing. It would be beneficial to be able to use aqueous inks in textured printing. Summary of the invention

[0005] The new inkjet printer combines aqueous ink and UV curable ink to produce textured prints. The printer includes a media transport device configured to move media through the printer; at least one actuator operatively connected to the media transport device, the at least one actuator configured to operate the media transport device to move the media through the printer; at least two printheads, each printhead having a plurality of ejectors and at least one printhead configured to eject drops of aqueous ink toward the media moving through the printer and at least one other printhead configured to eject drops of UV curable material toward the media after the drops of aqueous ink have landed on the media; a UV curing device configured to direct UV radiation to the media passing through the printer after the media has passed through the at least two printheads; and a thermal dryer configured to direct energy to the media passing through the printer after the media has passed through the UV curing device.

[0006] A method of operating a new inkjet printer produces a textured print using aqueous ink. The method includes operating at least one actuator operatively connected to a media transport device to move the media through the printer; operating at least one printhead having a plurality of ejectors to eject drops of aqueous ink toward the media moving through the printer; operating at least one other printhead having a plurality of ejectors to eject drops of UV curable material toward the media after the drops of aqueous ink have landed on the media; operating a UV curing device to direct UV radiation toward the media passing through the printer after the media has passed the printhead; and operating a thermal dryer to direct energy toward the media passing through the printer after the media has passed the UV curing device. BRIEF DESCRIPTION OF THE DRAWINGS

[0007] The foregoing aspects and other features of an inkjet printer and its method of operation for producing textured prints using aqueous inks and UV curable inks are explained in the following description in conjunction with the accompanying drawings.

[0008] Figure 1 An inkjet printer configured to produce textured prints using aqueous inks and UV curable inks is depicted.

[0009] Figure 2 is Figure 1 A side view of the configuration of a UV curing device or heat dryer used in a printer.

[0010] Figure 3 For operation Figure 1 Flow chart of a method of a system. DETAILED DESCRIPTION

[0011] For a general understanding of the inkjet printer and its uses disclosed herein and the details of the printer and its uses, reference is made to the accompanying drawings. In the drawings, like reference numerals indicate like elements.

[0012] As used herein, the terms "printer," "printing device," or "imaging device" generally refer to a device that produces an image on a print medium with a marking material (such as ink), and may encompass any such device, such as a digital copier, a fax machine, a multifunction machine, and the like. Image data generally includes information presented in electronic form and is used to operate an inkjet ejector to form an ink image on a print medium. Such data may include text, graphics, pictures, and the like. The operation of producing an image (e.g., graphics, text, photos, and the like) on a print medium with a colorant is generally referred to herein as printing or marking. The term "textured print" means a printed image having raised features or a coating that enhances the underlying image. The term "aqueous ink" means a marking material having a high percentage of water or solvent relative to the amount of colorant in the liquid dissolved or suspended in the ink.

[0013] Figure 1 A block diagram of an aqueous inkjet printer 100 is depicted that is configured to produce textured prints using aqueous ink and UV curable ink. The printer 100 includes at least two printhead arrays 104 (although the depicted printer has four such arrays), a UV curing device 108, a thermal heater 110, a media transport device 112, a pair of nip rollers 116 mounted around a member 120 extending in a cross-process direction across a media 124 carried by the media transport device 112, one or more actuators for driving the media transport device 112, and a controller 128 configured to operate the components of the printer 100. Although Figure 1 The system 100 shown in the drawings uses a single thermal dryer, but multiple thermal dryers and extensions of conveyor belts may also be provided. As used herein, the term "thermal dryer" refers to a configuration of drying components that can be operated to treat a printed substrate with heat to evaporate water or other solvents from a printed image. As used in this document, the words "drying" and "drying" mean using a form of energy to evaporate a liquid or solvent that can be directed along a predetermined path.

[0014] exist Figure 1In the embodiment of the present invention, the media conveying device 112 is implemented with an endless belt wrapped around two or more rollers, at least one of which is driven by one of the actuators 132 to rotate the belt around the roller. Other embodiments can be used for the media conveying device 112, such as a series of rotating nip rollers driven by one or more of the actuators 132. In some embodiments, the front end of the supply roller of the media is fed to the take-up roller at the end of the printer by the printer. A support member, either or both of the supply roller and the take-up roller are driven on the support member to move the media from the supply roller to the take-up roller in a known manner. As used in this document, the term "media" means a single substrate of the image receiving surface and a continuous substrate of the image receiving surface. As used herein, the term "cross-process direction" refers to a direction perpendicular to the direction in which the substrate moves through the print head, the cutting device, and the heat dryer that is also located in the plane of the substrate. As used herein, the term "process direction" refers to the direction in which the substrate moves through the print head, the cutting device, and the heat dryer that is also located in the plane of the substrate.

[0015] The printhead array 104 is configured and operated in a known manner to eject aqueous ink droplets onto a medium passing through the printhead array 104, thereby forming an ink image on the medium. The UV curing device 108 is configured to expose an image containing UV curable ink to electromagnetic radiation in a frequency range that at least partially cures the UV curable ink. In some embodiments, the UV curing device is a single radiator that emits a radiation pattern that is as wide as the widest medium printed by the printer in the cross-process direction. In other embodiments, the UV curing device is composed of a plurality of UV light radiators, which are arranged in an array having a width in the cross-process direction, and the width is equal to the widest medium printed by the printer. In these embodiments, the controller 128 can selectively activate the radiators in the array of the UV curing device 108 to expose areas printed with UV ink to radiation without irradiating non-UV ink areas with energy. One or more thermal dryers 110 uniformly heat the medium to a temperature sufficient to remove sufficient water from the aqueous ink in the printed image, so that the aqueous ink adheres to the medium and removes free radicals in the partially cured UV ink.

[0016] In previously known aqueous inkjet printers for texturing printing, the aqueous ink image is first heat treated to adhere the image to the substrate. After the heat treatment, the aqueous ink image passes through a print head, which sprays a UV curable ink or coating material on top of the fixed aqueous ink image. The UV curable ink or coating material is then exposed to curing radiation. However, this process is subject to oxygen inhibition of the curing process. This oxygen inhibition may only result in partial curing of the UV material. Because UV materials contain free radicals, partially cured images may irritate the skin of people removing the printed media, and offensive odors may permeate the environment surrounding the printer.

[0017] To address these issues, the printhead array 104 is configured with different material sources for ejection. For example, in one embodiment, four printhead arrays may be configured with aqueous inks of different colors, such as cyan, yellow, magenta, and black, and the fifth printhead array is configured to eject UV curable materials. The printhead array configured with aqueous ink is positioned to eject aqueous ink on the medium before the printhead array configured with UV curable materials ejects droplets of UV curable material on the aqueous image on the medium. The controller 128 uses the image data for the print job to operate the printheads in the printhead array 104, so that before droplets of UV curable ink or coating material are ejected onto the aqueous image, droplets of aqueous ink are ejected onto the medium to provide texture to the printed image. The combined aqueous ink / UV curable material image is then first exposed to UV curing radiation to fix the UV curable material to the aqueous ink image and the substrate. As used in this document, the term "printing" means exposing the UV curable material to an amount of UV radiation sufficient to only partially cure the UV material. The partially cured UV material remains in place to preserve the texturing effect in the printed image. Subsequent thermal drying of the combined aqueous ink / UV curable material image simultaneously fixes the aqueous ink to the substrate and removes free radicals from the UV curable material. The result is a texturing print that is safer and less objectionable than previously known texturing printed using UV curable materials.

[0018] In one embodiment, the hot dryer 110 is configured with an infrared radiator that directs infrared radiation to the entire area of ​​the passing medium. In another embodiment, the microwave radiator is configured to direct microwave radiation to the medium. In these embodiments using infrared or microwave radiators, the radiators can be arranged in the dryer 110 in an array as described above with reference to the UV curing device, so the controller 128 can selectively operate the radiator to change the amount of radiation irradiated to different areas of the composite printed image. The intensity is changed by the controller using the coverage area in the image derived from the image data used to operate the print head and the type of media used in the print job. Since the type of medium affects the absorptivity of the ink, the area receiving less radiation can absorb more ink than the area with more intense radiation. In other embodiments, one or more convection heaters or heating lamps can be used, and the heated air generated by the heater is directed to the passing medium by a blower, a fan or other source of positive air flow. Compared with the embodiment with an array of radiators that can be selectively activated, these embodiments are not so easy to change the heat applied to the composite image. In all embodiments of the printer, the controller 128 is configured with programming instructions stored in a memory operatively connected to the controller, which, when executed, causes the controller to operate the actuator 132 and change the speed at which the media moves through the curing device 108 and the dryer 110. By slowing down the media, exposure to UV radiation can be delayed, thereby providing more time for the ink to be absorbed into the media. This absorption changes the height of the ink on the media and the corresponding texture produced on the media. In addition, slowing down the media speed through the UV curing device and the dryer increases exposure to radiation and heat, respectively, to remove free radicals from the media.

[0019] Figure 2 It is shown that it can be used for Figure 11 is a side view of an embodiment of a thermal dryer 110 in a printer of FIG. The thermal dryer 110 includes a housing 204, a plurality of members 208, and a drying element 212 mounted to the member 208. The housing 204 encloses a volume of air and has an opening that communicates with a space adjacent to the medium as they pass through the housing 204. The members 208 depicted in the figure extend across the housing 204 in a transverse process direction, although the members can extend in the process direction, provided that the distance separating the members from each other is not greater than the width of the area heated by each of the drying elements 212. This type of member / heating element configuration ensures that the entire or a majority of the entire surface area of ​​the media zone passing through is heated. This same type of configuration can be used for UV radiators arranged in an array in a UV curing device as previously described. As described above, the drying element can be an infrared radiator, a microwave radiator, a heating lamp, a convection heater, a blower, etc. For embodiments of the drying element implemented with a heating lamp or a convection heater, a pressurized air source can be included to direct the heat generated by the drying element to the medium. The housing 204 may also include a vent opening 216, and a negative pressure source 205 may be connected to the vent opening to draw evaporated water, solvents, and free radicals from the air within the volume of the housing 204. The housing 204 helps to retain the heated or dry air generated by the drying element to dry the ink image and release free radicals from the UV curable ink.

[0020] The operation and control of the various subsystems, components and functions of the printer 100 are performed with the aid of a controller 128. The controller 128 is operatively connected to the printhead module 104 (and thus to the printhead), the UV curing device 108, the thermal dryer 110, and components of the actuator 132 that rotates the media transport device 112 and the nip roller 116. For example, the controller 128' is a self-contained, dedicated microcomputer having a central processor unit (CPU) with electronic data storage and a display or user interface (UI) 50. For example, the controller 128 includes sensor input and control circuitry and pixel placement and control circuitry. In addition, the CPU reads, captures, prepares and manages the image data flow between an image input source such as a scanning system or an in-line or workstation connection and the printhead modules 34A-34D. Thus, the controller 128' is the main multitasking processor for operating and controlling all other machine subsystems and functions in the printing system 100. To perform these operations, the controller 128 uses print job data, such as media type, ink type, etc., along with image data for operating the printing performed by the printhead.

[0021] The controller 128 can be implemented with a general or special programmable processor that executes programming instructions. The instructions and data required to perform the programming functions are stored in a memory that is operatively connected to the processor or controller. The processor, the memory of the processor, and the interface circuit configuration controller perform the operations described below. These components can be arranged on a printed circuit card, or arranged as a circuit in an application-specific integrated circuit (ASIC). Each circuit can be implemented by a separate processor, or multiple circuits can be implemented on the same processor. Alternatively, these circuits can be implemented by discrete components or circuits arranged in a very large scale integrated (VLSI) circuit. In addition, the circuits described herein can be implemented with a combination of a processor, an ASIC, discrete components, or a VLSI circuit.

[0022] Figure 3 The process for operating the system 100 to print a textured print image on a medium is shown in the flowchart of the method. The method is performed by the controller 128, which executes programmed instructions stored in a memory operatively connected to one or more controllers, and when the one or more controllers execute the instructions, they process data and operate components operatively connected to the controller to perform the tasks shown in the flowchart of the method.

[0023] Process 300 begins by receiving print job information, such as media type, ink type, and image data to be used to operate the print head to eject drops of aqueous ink and drops of UV curable material in a pattern corresponding to the image data (box 304). Media transport begins through the printer past the media (box 308) and the print head is operated to form an aqueous ink image on the media and then eject drops of UV curable material onto the aqueous image in a pattern corresponding to the image data of the textured pattern received in the print job data (box 312). The UV curing device is operated to fix the UV material pattern to the aqueous image and the media (box 316). The actuators of the thermal dryer and the media transport device are operated to fix the aqueous image to the media and remove free radicals from the aqueous ink image and the UV material on the media (box 320). Operation of the thermal dryer includes operating a negative pressure source to draw evaporated water, solvents, and released free radicals from the thermal dryer so they can be safely discharged outside the environment of the printer. Additionally, operation of the thermal dryer includes using the image data of the aqueous ink image and the UV curable material pattern to selectively activate and deactivate the radiators in the UV during the device and the drying elements in the thermal dryer. When the print job is complete (block 324), the process stops.

[0024] It should be understood that variations or alternatives of the above disclosed and other features and functions may be desirably combined into many other different systems, applications or methods. Those skilled in the art may subsequently make various currently unforeseen or unanticipated substitutions, modifications, changes or improvements, which are also intended to be covered by the following claims.

Claims

1. A printer, comprising: a media transport device configured to move media through the printer in a process direction; at least one actuator operatively connected to the media transport device, the at least one actuator configured to operate the media transport device to move the media through the printer in the process direction; at least two printhead arrays arranged to follow each other in the process direction, each printhead in each of the at least two printhead arrays having a plurality of ejectors and at least one printhead array being configured to eject drops of aqueous ink toward the medium moving through the printer and at least one other printhead array being configured to eject drops of UV curable material toward the medium after the drops of aqueous ink have landed on the medium; a UV curing device configured to direct UV radiation toward the media passing through the printer after the media has passed through the at least two printhead arrays, the UV curing device having a housing, a plurality of members extending across the housing, and a plurality of UV radiators, the housing having a width extending in a cross-process direction across a distance equal to the widest media printable by the printer, the plurality of UV radiators mounted to each of the plurality of members extending across the housing, each UV radiator configured to direct UV radiation toward the media moved by the media transport device through the housing of the UV curing device in the process direction; a thermal dryer configured to direct energy to the media passing through the thermal dryer in the process direction after the media has passed through the UV curing device, the thermal dryer comprising a housing having a plurality of members extending across the housing of the thermal dryer, an opening, a negative pressure source, and a plurality of drying elements, the housing having a plurality of members extending across the housing of the thermal dryer, the negative pressure source connected to the opening in the housing to draw evaporated liquid and free radicals from the thermal dryer, the plurality of drying elements mounted to each of the plurality of members extending across the housing of the thermal dryer, each drying element configured to direct energy to the media passing through the housing of the thermal dryer; as well as A controller operatively connected to the at least two print head arrays, the at least one actuator, the UV curing device, the negative pressure source and the thermal dryer, the controller being configured to: operating the at least one actuator to operate the media transport device to move media through the printer in the process direction; using image data to operate the ejectors in the at least two printhead arrays to eject drops of aqueous ink and drops of UV curable material toward the media passing through the printer; operating the UV curing device to fix the UV curable material to the aqueous ink on the medium passing through the printer; using the image data to selectively operate the UV radiator in the UV curing device to fix the UV curable material to the aqueous ink as the media passes through the housing of the UV curing device in the process direction; operating the thermal dryer to evaporate liquid from the aqueous ink on the medium as the medium passes through the thermal dryer in the process direction and to release free radicals from the UV curable material after the UV curable material has been fixed to the aqueous ink; as well as The negative pressure source is operated to draw the vaporized liquid and free radicals through the opening in the housing. 2 . The printer according to claim 1 , wherein the plurality of members extend in a process direction within the housing of the thermal dryer.

3. The printer of claim 1, wherein the plurality of members extend in a cross-process direction within the housing of the thermal dryer. The printer of claim 3 , wherein the drying element is a microwave radiator.

5. The printer of claim 3, wherein the drying element is an infrared radiator.

6. The printer of claim 3, wherein the drying element is a convection heater.

7. The printer according to claim 1, wherein the plurality of members extend in a process direction within the housing of the UV curing device.

8. The printer of claim 1, wherein the plurality of members extend in a cross-process direction within the housing of the UV curing device.

9. The printer according to claim 1, wherein the controller is further configured to: The at least one actuator of the media transport device is operated to slow down the speed at which the media enters the UV curing device.

10. The printer according to claim 9, wherein the controller is further configured to: The at least one actuator of the media transport device is operated to slow the speed at which the media passes through the UV curing device.

11. The printer according to claim 10, wherein the controller is further configured to: The at least one actuator of the media transport device is operated using the image data and data corresponding to the type of media moved by the media transport device.

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