JP2010069706A - Image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image forming apparatus which allows improvement in durability of an image formed on a recording medium. <P>SOLUTION: Ink receiving particles 16 are supplied from a particle supply device 18 to an intermediate transfer belt 12, to form an ink receiving particle layer 16A. The ink receiving particle layer 16A whose thickness is made a decided thickness by a pressure roll 14 is conveyed to a position facing an inkjet recording head 20 of each color and an ink droplet of each color based on image information is discharged from the inkjet recording heads 20, to form a color image. Further, a curing liquid applying head 26 ejects a curing liquid for curing the ink receiving particles 16 to the whole area of the ink receiving particle layer 16A, and the ink receiving particle layer 16A to which the curing liquid is applied is cured while forming an ion cross-linked structure. Thus, the durability of the image formed on the sheet member P can be improved. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an image forming apparatus.

  In Patent Document 1, a liquid that is cured by radiation is applied to the surface of a recording medium after droplets are ejected from an ink jet recording head to the recording medium, and an image is formed on the recording medium. An image forming apparatus for irradiating a medium with radiation is described.

Thus, the durability of the image formed on the recording medium is improved by applying the liquid that is cured by radiation and further curing the liquid by irradiating the radiation.
JP 2000-272108 A

  An object of the present invention is to improve the durability of an image formed on a recording medium.

  An image forming apparatus according to a first aspect of the present invention stores an intermediate transfer member and liquid receptive particles for receiving droplets, and forms a layer of the liquid receptive particles on the intermediate transfer member. A droplet discharge head that discharges droplets from a nozzle onto the liquid receptive particle layer supplied onto the intermediate transfer body by the particle supply device, and the droplets discharged by the droplet discharge head A transfer member that transfers a layer of liquid receptive particles to a recording medium, and a curing that imparts a curable liquid that cures the liquid receptive particles to the layer of liquid receptive particles discharged from the nozzle of the droplet discharge head. An ionic liquid applying means.

  The image forming apparatus according to a second aspect of the present invention is the image forming apparatus according to the first aspect, wherein the curable liquid applying unit is formed on the layer of the liquid receptive particles transferred to the recording medium by the transfer member. It is characterized by giving.

  An image forming apparatus according to a third aspect of the present invention is the image forming apparatus according to the first or second aspect, further comprising a drying unit that dries a layer of liquid receptive particles transferred to a recording medium by the transfer member, and the curable property. The liquid applying unit applies the curable liquid to the layer of the liquid receptive particles dried by the drying unit.

  According to a fourth aspect of the present invention, in the image forming apparatus according to the first or second aspect, the layer of liquid receptive particles transferred to the recording medium by the transfer member is heated and pressurized to be fixed to the recording medium. A heat and pressure fixing member is provided, and the curable liquid applying means applies the curable liquid to the layer of the liquid receptive particles fixed on the recording medium by the heat and pressure fixing member.

  The image forming apparatus according to a fifth aspect of the present invention is the image forming apparatus according to the fourth aspect, wherein the curable liquid applying unit applies the curable liquid in contact with the layer of the liquid receptive particles on which the image is formed. It is a contact-type curable liquid provision means.

  According to the image forming apparatus of the first aspect of the present invention, the durability (particularly the scratch resistance and water resistance) of the image formed on the recording medium can be improved as compared with the case where this configuration is not provided. it can.

  According to the image forming apparatus of the second aspect of the present invention, the durability of the image formed on the recording medium can be effectively improved as compared with the case where this configuration is not provided.

  According to the image forming apparatus of the third aspect of the present invention, the curable liquid is efficiently absorbed in the layer of the liquid receptive particles and the durability is further improved as compared with the case where this configuration is not provided. it can.

  According to the image forming apparatus of claim 4 of the present invention, a curable liquid applying means for applying a curable liquid while touching the layer of the liquid receptive particles is employed as compared with the case where this configuration is not provided. Can do.

  According to the image forming apparatus of the fifth aspect of the present invention, the amount of the curable liquid to be consumed can be reduced as compared with the case where this configuration is not provided.

  An example of the image forming apparatus according to the first embodiment of the present invention will be described with reference to FIGS.

(overall structure)
As shown in FIG. 1, the image forming apparatus 10 according to the first embodiment includes an intermediate transfer belt 12 as an endless belt-like intermediate transfer member, and an adhesive layer that forms an adhesive layer on the surface of the intermediate transfer belt 12. An applying device 24, a particle supplying device 18 for supplying ink receiving particles 16 as liquid receiving particles to the region to which the adhesive layer of the intermediate transfer belt 12 has been applied to form an ink receiving particle layer 16A, and an intermediate transfer belt. A pressure roll 14 that pressurizes the ink-receptive particle layer 16A applied on the surface 12 to a predetermined thickness, and an ink jet that ejects ink droplets (droplets) onto the ink-receptive particle layer 16A to form an image. Applying a curable liquid as a curable liquid applying means for applying a curable liquid for curing the ink receiving particles to the recording head 20 and the ink receiving particle layer 16A on which an image is formed. A transfer member 22 for transferring the ink-receptive particle layer 16A on which the ink droplets are ejected onto the sheet member P by applying a pressure or the like by superimposing the recording medium 26 and the sheet member P as a recording medium on the intermediate transfer belt 12. And.

  Further, downstream of the transfer member 22, the ink receiving particles 16 remaining on the surface of the intermediate transfer belt 12 are removed and collected, and foreign matters other than the particles (such as paper dust on the sheet member P) are removed and collected. A cleaning device 28 is provided.

(Intermediate transfer belt)
The intermediate transfer belt 12 is formed with a 400 μm thick ethylene propylene rubber (EPDM) surface layer on a 100 μm thick polyimide film base layer, and a rotationally driven driving roll 30 and a driven rotating driven roll 34. , And a follower pressurizing roll 22B, which will be described later, is rotated.

(Adhesive layer application device)
The adhesive layer applying device 24 is provided with a housing 24E for storing the adhesive 24D. In addition, the stored adhesive 24D is applied to the surface of the intermediate transfer belt 12 while rotating the stored adhesive 24D. A supply roll 24C is provided. Further, a plate-like blade 24B for regulating the amount of the adhesive 24D supplied to the intermediate transfer belt 12 by the supply roll 24C is provided downstream of the supply roll 24C.

  The adhesive layer applying device 24 may be continuously in contact with the intermediate transfer belt 12 for the purpose of continuously forming images on the sheet member P, or may be used for intermediate transfer. It is good also as a structure which can be spaced apart from the belt 12. FIG. Furthermore, the adhesive 24D may be supplied to the adhesive layer applying device 24 from an independent liquid supply system (not shown) so that the supply of the adhesive 24D is not interrupted.

  Moreover, as adhesive 24D, glue, an organic solvent (preferably surface tension 40mN / m or less, viscosity 20mPas or more), etc. can be used, for example.

(Particle supply device)
The particle supply device 18 is a device that supplies the ink receiving particles 16 to the surface of the intermediate transfer belt 12 to form the ink receiving particle layer 16 </ b> A on the intermediate transfer belt 12.

  The particle supply device 18 is provided with a supply roll 18A at a portion facing the intermediate transfer belt 12, and further provided with a blade 18B for pressing the ink receiving particles 16 on the surface of the supply roll 18A. The blade 18B also has a function of regulating the layer thickness of the ink receiving particles 16 supplied to the surface of the supply roll 18A. Further, a cleaning roll 18C for cleaning residual particles remaining on the surface of the supply roll 18A without moving to the surface of the intermediate transfer belt 12 while being driven and rotated with the supply roll 18A is provided adjacent to the supply roll 18A. .

  The supply roll 18A can be a solid aluminum roll, and the blade 18B can be a metal plate (SUS or the like) to which urethane rubber is attached in order to apply pressure. The blade 18B is in contact with the supply roll 18A by a doctor blade method.

  The ink receiving particles 16 are transported to a portion facing the surface of the intermediate transfer belt 12 by the supply roll 18A, and the pressing force of the supply roll 18A and the adhesive of the adhesive 24D supplied to the surface of the intermediate transfer belt 12 are used. It is configured to move to the surface of the intermediate transfer belt 12 by force. As a result, the ink receiving particle layer 16 </ b> A is formed on the intermediate transfer belt 12.

(Inkjet recording head)
The inkjet recording head 20 includes an inkjet recording head 20Y that ejects yellow ink droplets, an inkjet recording head 20M that ejects magenta ink droplets, an inkjet recording head 20C that ejects cyan ink droplets, and a black ink droplet. The ink jet recording head 20 </ b> K that discharges ink and the ink jet recording head 20 </ b> T that discharges transparent liquid droplets to a non-image portion are configured. These ink jet recording heads 20 are driven by piezoelectric (piezo), thermal, or the like.

  As shown in FIG. 2, the ink jet recording head 20 that applies ink droplets to the ink receiving particle layer 16 </ b> A (see FIG. 1) based on image information includes a nozzle 40 that ejects ink droplets, and ink to the nozzle 40. The supply flow path 42 which supplies is supplied.

  Specifically, the nozzle 40 is provided on the nozzle surface 44A of the nozzle plate 44 formed of polyimide resin, and the supply flow path 42 is formed by opening a plurality of laminated plates 46.

  Further, a counterbore plate 48 made of SUS provided with a circular hole having a diameter larger than that of the nozzle 40 is laminated on the nozzle plate 44. The counterbore plate 48 and the nozzle surface 44A opened from the opening of the counterbore plate 48 are provided with a fluororesin coat 50 as a water repellent layer.

(Curing liquid application head)
As shown in FIG. 1, the curable liquid application head 26 is driven by a piezoelectric type (piezo), a thermal type, or the like in the same manner as the inkjet recording head 20, and curable liquid that cures the ink receiving particles 16 is ink jet type. The ink receptive particle layer 16A is jetted from the nozzle (not shown).

  In the case where the ink receiving particles 16 contain an organic resin having an anionic polar group, for example, a curable liquid containing a cationic substance can be adopted as the curable liquid. By applying a curable liquid containing a cationic substance to the ink receiving particles 16, two or more anionic polar groups form an ionic cross-linked structure by cations supplied from the cationic substance, and the ink receiving particles This is because 16 is cured.

  When the ink receiving particles 16 contain an organic resin having a cationic polar group, for example, a curable liquid containing an anionic substance can be adopted as the curable liquid. By applying a curable liquid containing an anionic substance to the ink receiving particles 16, two or more cationic polar groups form an ion cross-linked structure by anions supplied from the anionic substance, and the ink receiving particles This is because 16 is cured.

(Transfer member)
The transfer member 22 includes a heating roll 22A that sandwiches the sheet member P via the intermediate transfer belt 12 and incorporates a heating source, and a driven pressure roll that is disposed with the intermediate transfer belt 12 interposed between the heating roll 22A. 22B is provided. The driven pressure roll 22B is pressurized toward the heating roll 22A via the intermediate transfer belt 12 and the sheet member P.

  As the heating roll 22A and the driven pressure roll 22B, for example, an outer surface of an aluminum core covered with silicone rubber and further covered with a PFA tube can be used.

  With the above configuration, when the ink receiving particle layer 16A on the intermediate transfer belt 12 is transferred to the sheet member P by heating and pressurization by the transfer member 22, the ink receiving particle layer 16A on the intermediate transfer belt 12 is heated. Is added to increase the viscosity of the ink receptive particle layer 16A, and the sheet member P is nipped and conveyed while pressure is applied, so that the ink receptive particle layer 16A is attached to the sheet member P. Thus, the ink receiving particle layer 16A on the intermediate transfer belt 12 is transferred to the sheet member P.

  As the sheet member P, any of a permeable medium (for example, plain paper, inkjet coated paper, etc.) and a non-permeable medium (for example, art paper, resin film, etc.) can be applied. Further, the sheet member P is not limited to these, and includes industrial products such as a semiconductor substrate.

(Function)
Next, the operation of forming an image on the sheet member P with the above configuration will be described.

  As shown in FIG. 1, first, the intermediate transfer belt 12 is rotated by a driving force of a driving roll 30 that is rotationally driven, and an adhesive layer 24 A is formed on the surface of the intermediate transfer belt 12 by the adhesive layer applying device 24. Specifically, the adhesive 24 </ b> D is supplied to the surface of the intermediate transfer belt 12 by the supply roll 24 </ b> C of the adhesive layer applying device 24. Further, the layer thickness of the adhesive 24D supplied to the surface of the intermediate transfer belt 12 by the blade 24B is defined, and the adhesive layer 24A is formed.

  Further, the ink receiving particles 16 are supplied from the supply roll 18A of the particle supply device 18 to the surface of the intermediate transfer belt 12 on which the adhesive layer 24A is formed, thereby forming the ink receiving particle layer 16A. Further, the pressure roll 14 that is driven to rotate presses the ink receiving particle layer 16 </ b> A while rotating to a predetermined thickness.

  The ink receptive particle layer 16A having a predetermined thickness is conveyed to a position facing the inkjet recording head 20 of each color, and each color of each color based on image information from the inkjet recording heads 20K, 20C, 20M, 20Y, and 20T. Ink droplets are ejected to form a color image.

  Further, the curable liquid application head 26 ejects a curable liquid for curing the ink receiving particles 16 over the entire area of the ink receiving particle layer 16A, and the ink receiving particle layer 16A to which the curable liquid is applied has an ionic cross-linking structure. Form and cure. The applied ink receiving particle layer 16A to which the curable liquid is applied is transferred together with the color image to the sheet member P that is taken out from the paper feed tray 36 and nipped and conveyed while being heated and pressurized by the transfer member 22. The Further, the sheet member P to which the ink receptive particle layer 16 </ b> A has been transferred is conveyed and discharged to the discharge tray 38.

  Although the present invention has been described in detail with respect to specific embodiments, the present invention is not limited to such embodiments, and various other embodiments are possible within the scope of the present invention. It is clear to the contractor. For example, in the above-described embodiment, the transfer member 22 is provided with a heating roll 22A containing a heating source and a driven pressure roll 22B pressurized to the heating roll 22A side. For example, the ink receiving particle layer 16 </ b> A may be transferred to the sheet member P simply by applying pressure without using a heating source.

  In the above-described embodiment, the curable liquid is directly applied to the ink receiving particle layer 16A. However, the present invention is not particularly limited thereto. For example, the curable liquid is applied in advance to the sheet member P before transfer and cured. An indirect liquid may be indirectly applied to the ink receiving particle layer 16A.

  In the above embodiment, although not particularly limited, the inkjet recording head may be a fixed recording head (FWA) having a sheet member width as a printing area, and the sheet member while moving in the width direction of the sheet member P. It may be a scanning recording head (PWA) that discharges droplets onto P.

  In the above embodiment, the curable liquid application head 26 adopting the ink jet method as the curable liquid application unit has been described as an example. However, an ultrasonic method, a spray method, or the like may be used.

  Next, a second embodiment of the image forming apparatus of the present invention will be described with reference to FIG.

  In addition, about the same member as 1st Embodiment, the same code | symbol is attached | subjected and the description is abbreviate | omitted.

  As shown in FIG. 3, in this embodiment, unlike the first embodiment, the curable liquid application head 26 applies the curable liquid to the ink receiving particle layer 16 </ b> A transferred to the sheet member P.

  The transfer member 56 includes a rotating roll 56A that supports the sheet member P, and a driven pressure roll 56B that is pressurized toward the rotating roll 56A via the intermediate transfer belt 12 and the sheet member P. .

  Next, a third embodiment of the image forming apparatus of the present invention will be described with reference to FIG.

  In addition, about the same member as 2nd Embodiment, the same code | symbol is attached | subjected and the description is abbreviate | omitted.

  As shown in FIG. 4, in this embodiment, unlike the second embodiment, a radiant heater 60 as a drying means is provided before the step of applying the curable liquid from the curable liquid application head 26. .

  Specifically, the radiant heater 60 includes a heat generating portion 60A and a fan 60B that blows air heated by the heat generating portion 60A to the ink receiving particle layer 16A.

  By providing the radiant heater 60 before the step of applying the curable liquid from the curable liquid application head 26, the penetration of the curable liquid is promoted, and the ion reaction is effectively performed.

  Although the present invention has been described in detail with respect to specific embodiments, the present invention is not limited to such embodiments, and various other embodiments are possible within the scope of the present invention. It is clear to the contractor. For example, in the above embodiment, a radiant heater is used as the drying means, but an infrared lamp, a microwave generator, a laser device, or the like may be used.

  Next, a fourth embodiment of the image forming apparatus of the present invention will be described with reference to FIG.

  In addition, about the same member as 2nd Embodiment, the same code | symbol is attached | subjected and the description is abbreviate | omitted.

  As shown in FIG. 5, unlike the second embodiment, heating application as a fixing unit that heats and pressurizes the ink receptive particle layer 16 </ b> A transferred to the sheet member P by the transfer member 22 and fixes it to the sheet member P is performed. A pressure fixing member 64 is provided. The heating and pressing fixing member 64 includes a heating roll 64A containing a heating source and a pressing roll 64B provided to face the heating roll 64A.

  Further, the curable liquid applying means for applying the curable liquid to the ink receiving particle layer 16A fixed by the heat and pressure fixing member 64 is not a curable liquid applying head arranged away from the ink receiving particle layer 16A. The curable liquid application roll 66 is an example of a contact-type curable liquid application unit that applies the curable liquid in contact with the ink receiving particle layer 16A.

  Further, a curable liquid supply member 68 that supplies a curable liquid to the outer peripheral surface of the curable liquid application roll 66 adjacent to the rotationally driven curable liquid application roll 66, and a sheet member for the curable liquid application roll 66. A driven roll 70 is provided so as to face the P.

  As described above, since the ink-receptive particle layer 16A on which the image is formed is heated and melted and fixed, the adhesiveness of the image surface is lost. Therefore, even if the sheet member P is conveyed while touching the image, the image is damaged. There is nothing.

  Although the present invention has been described in detail with respect to specific embodiments, the present invention is not limited to such embodiments, and various other embodiments are possible within the scope of the present invention. It is clear to the contractor. For example, in the above embodiment, the curable liquid is applied by the curable liquid application roll 66 in contact with the ink receiving particle layer 16A. However, the curable liquid may be applied by a plate-like blade or the like.

The following effects can be given as other effects in the present embodiment.
(1) By curing the ink-receiving particle layer 16A on which the image is formed, when the sheet member P on which the image is formed is superimposed on another sheet member P, the formed image is another sheet member P. It is possible to prevent the sheet member P and the sheet member P stacked on the sheet member P from blocking.
(2) When the curable liquid application head 26 applies the curable liquid after ink absorption (after image formation), the occurrence of ink absorption inhibition can be prevented.
(3) By drying the ink receptive particle layer 16A in the previous step of the curable liquid application head 26, the ink receptive particles 16 and the ink color material can be agglomerated, and the color material (pigment) and the space between the particles Further, the fixing force between the coloring materials, between the particles, and between the sheet member P and the particles increases.
(4) Further, by increasing the fixing force in this manner, it is possible to prevent the image from peeling off or cracking the image when the sheet member P is bent, and to further improve the scratching property and the fixing property.
(5) The surface of the ink receiving particle layer 16A and the curable liquid are efficiently reacted by drying the ink receiving particle layer 16A before the step of applying the curable liquid from the curable liquid applying head 26. As a result, high-speed processing becomes possible, and the durability of the image is enhanced by applying a small amount of curable liquid.

1 is a schematic configuration diagram illustrating an image forming apparatus according to a first embodiment of the present invention. 1 is a cross-sectional view of an ink jet recording head employed in an image forming apparatus according to a first embodiment of the present invention. FIG. 5 is a schematic configuration diagram illustrating an image forming apparatus according to a second embodiment of the present invention. FIG. 5 is a schematic configuration diagram illustrating an image forming apparatus according to a third embodiment of the present invention. FIG. 6 is a schematic configuration diagram illustrating an image forming apparatus according to a fourth embodiment of the present invention.

Explanation of symbols

10 Image forming apparatus 12 Intermediate transfer belt (intermediate transfer member)
16 Ink receiving particles (liquid receiving particles)
16A ink receptive particle layer (layer of liquid receptive particles)
18 Particle supply device 20 Inkjet recording head (droplet discharge head)
22 transfer member 22A heating roll 22B driven pressure roll 26 curable liquid application head (curable liquid application means)
40 Nozzle 56 Transfer member 56A Rotating roll 56B Driven pressure roll 60 Radiant heater (drying means)
64 Heating and pressure fixing member 64B Pressure roll 64A Heating roll 66 Contact-type curable liquid applying means

Claims (5)

An intermediate transfer member;
A particle supply device for storing liquid receptive particles for receiving droplets and forming a layer of the liquid receptive particles on the intermediate transfer member;
A liquid droplet ejection head for ejecting liquid droplets from a nozzle to the liquid receptive particle layer supplied onto the intermediate transfer member by the particle supply device;
A transfer member for transferring a layer of the liquid receptive particles, onto which a droplet is discharged by the droplet discharge head, to a recording medium;
A curable liquid applying means for applying a curable liquid for curing the liquid receptive particles to the layer of the liquid receptive particles discharged from the nozzle of the droplet discharge head;
An image forming apparatus provided therewith.   The image forming apparatus according to claim 1, wherein the curable liquid applying unit applies the curable liquid to the layer of the liquid receptive particles transferred to a recording medium by the transfer member. A drying means for drying the layer of liquid receptive particles transferred to the recording medium by the transfer member;
The image forming apparatus according to claim 1, wherein the curable liquid applying unit applies the curable liquid to the layer of the liquid receptive particles dried by the drying unit. A heating and pressing fixing member is provided for heating and pressing the layer of liquid receptive particles transferred to the recording medium by the transfer member and fixing the layer to the recording medium;
The image forming apparatus according to claim 1, wherein the curable liquid applying unit applies the curable liquid to a layer of the liquid receptive particles fixed on a recording medium by the heat and pressure fixing member.   The image forming apparatus according to claim 4, wherein the curable liquid applying unit is a contact-type curable liquid applying unit that applies the curable liquid in contact with the layer of the liquid receptive particles on which an image is formed.

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