JP2016155288A - Image surface recovery roller and manufacturing method of the same, roller set and image surface recovery method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image surface recovery roller and a manufacturing method of the same, a roller set and an image surface recovery method capable of reducing, in short-time processing, visibility of scratches on a surface of an image recorded with ink droplets injected in an ink-jet printing, while suppressing occurrence of printing unevenness.SOLUTION: An image surface recovery roller recovers an image which is recorded with droplets injected on the recording surface of a recording medium, by rolling on the image surface depressing scratches to reduce visibility of the scratches. Thereby, the image surface recovery roller solves the above-mentioned problem, with a plurality of irregularly arranged convex shapes on its outer peripheral surface corresponding to convex shapes on the image surface.SELECTED DRAWING: Figure 6

Description

  The present invention relates to an image surface repair roller, a manufacturing method thereof, a roller set, and an image surface repair method, and more particularly to a technique for repairing a scratch on the surface of an image recorded by an inkjet method.

  2. Related Art An ink jet recording apparatus that records an image by ejecting ink onto a recording medium by an ink jet method is known. When a scratch is generated on the surface of an image recorded by the ink jet method, the quality of the image is impaired by visually recognizing the scratch.

  For such a problem, Patent Document 1 describes a technique for repairing a scratch by determining a scratch on an image printed on a print medium and reprinting the scratch area on the same print sample. ing.

JP2012-129823A

  However, the technique described in Patent Document 1 has a problem that the processing for repairing the scratches is complicated and takes time.

  SUMMARY OF THE INVENTION The present invention has been made in view of such circumstances, and an image surface repair roller for reducing the visibility of scratches on the surface of an image recorded by ejecting ink using an ink jet method and a method for manufacturing the same. An object of the present invention is to provide a roller set and an image surface repair method.

  In order to achieve the above object, one aspect of the image surface repair roller is a convex shape of the surface of the image recorded on the recording surface of the recording medium, which is formed by ink droplets ejected by an ink jet method. A plurality of concave shapes corresponding to the shape are irregularly arranged on the outer peripheral surface.

  The image surface repair roller according to this aspect presses the outer peripheral surface against scratches on the surface of the image formed by ink droplets on the recording surface of the recording medium, and relatively rotates the recording medium and the image surface repair roller. In this way, the scratches on the surface of the image are repaired. According to this aspect, since a plurality of concave shapes corresponding to the convex shape of the surface of the image are irregularly arranged on the outer peripheral surface, the recording medium and the image surface repair roller are pressed against the outer peripheral surface against scratches on the image surface. , And the relative visibility of scratches on the surface of the image can be reduced in a short time.

  Here, the convex shape refers to the shape of a portion that is not in contact with the recording surface or other ink droplets, and that is convex with respect to the recording surface, among the ink droplets that are ejected onto the recording surface. One convex shape is formed by one ink droplet.

  Further, the relative rotation of the recording medium and the image surface repair roller means a mode in which the image surface repair roller rotates while the recording medium is fixed, and the recording medium is fixed with the position of the image surface repair roller fixed. In which the image surface repair roller is rotated, the recording medium is rotated while the image surface repair roller is fixed, the image surface repair roller is rotated while the recording medium is running, and the recording medium And an image surface repairing roller are rotated together.

  The pressing of the outer peripheral surface against the scratch on the surface of the image is not limited to the mode of pressing the outer peripheral surface only against the scratch on the surface of the image, and the outer peripheral surface is pressed against an area other than the scratch on the surface of the image and the scratch. Embodiments are also included.

  The concave shape is preferably a shape obtained by inverting the shape and size of the convex shape on the surface of the image. That is, as an example of the “concave shape corresponding to the convex shape”, unevenness can be appropriately suppressed by using a plurality of irregularly arranged convex shapes and shapes having inverted sizes.

  The concave shape is preferably such that the concave edges adjacent to each other are arranged in an irregular shape. As a result, the convex shape of the image surface is equal between the area where the outer peripheral surface of the image surface repair roller is pressed and the other area, and the area where the image surface repair roller is pressed is prevented from being recognized as unevenness. can do.

  The concave shape is preferably a shape in which the convex shape and the size corresponding to the volume of the ink droplet are reversed. Thereby, generation | occurrence | production of a nonuniformity can be suppressed appropriately.

  It is preferable that the entire outer peripheral surface has a concave shape. Thereby, generation | occurrence | production of a nonuniformity can be suppressed appropriately.

  It is preferable that the diameter of the image surface repair roller gradually decreases from the axial center of the image surface repair roller toward both ends. As a result, the boundary between the area where the outer peripheral surface of the image surface repair roller is pressed and the other area can be made ambiguous, and the area where the image surface repair roller is pressed cannot be recognized.

  The axial length of the image surface repair roller is preferably shorter than the vertical length and the horizontal length of the recording surface of the recording medium. As a result, the image surface repair roller can be pressed only on a part of the region including the scratch on the image.

  It is preferable to include a support unit that rotatably supports the image surface repair roller, and a handle unit that is fixed to the support unit and is gripped by the user. As a result, the user can grip the handle and press the outer peripheral surface of the image surface repair roller against the surface of the image so that the image can be rotated, thereby reducing the visibility of scratches on the surface of the image in a short time. be able to.

  In order to achieve the above object, one aspect of the roller set is a convex shape of the surface of the image recorded on the recording surface of the recording medium, and a convex shape formed by ink droplets ejected by an inkjet method. In a roller set including a plurality of image surface repair rollers in which a plurality of corresponding concave shapes are irregularly arranged on the outer peripheral surface, each of the plurality of image surface repair rollers corresponds to a convex shape formed by ink droplets having different volumes. A plurality of concave shapes are irregularly arranged.

  According to this aspect, since there are provided a plurality of image surface repair rollers in which a plurality of concave shapes corresponding to the convex shapes formed by ink droplets having different volumes are irregularly arranged, the volume of the ink droplets forming the image By selecting an image surface repair roller corresponding to the image, it is possible to appropriately reduce the visibility of scratches on the surface of the image in a short time.

  In order to achieve the above object, one aspect of an image surface repair method is an image recorded on a recording surface of a recording medium, wherein the surface of an image formed by ink droplets ejected by an ink jet method is scratched. The detection step for detecting and the outer peripheral surface of the image surface repairing roller having a convex shape on the surface of the image, the concave shape corresponding to the convex shape formed by ink droplets being irregularly arranged on the outer peripheral surface. And a rotation traveling process in which the recording medium and the image surface repair roller are relatively rotated while being pressed against each other.

  According to this aspect, a scratch on the surface of the image is detected, and a plurality of concave shapes corresponding to the convex shape formed by the ink droplets are irregularly arranged on the outer peripheral surface. Since the recording medium and the image surface repair roller are rotated relative to each other by pressing the outer surface of the image surface repair roller against the scratch, the visibility of the image surface scratch can be reduced in a short time. Can do.

  In order to achieve the above object, one aspect of the manufacturing method of the image surface repair roller is a convex shape of the surface of the image recorded on the recording surface of the recording medium, which is formed by ink droplets ejected by an ink jet method. In a method for manufacturing an image surface repair roller in which a plurality of concave shapes corresponding to the projected shape are irregularly arranged on the outer peripheral surface, a lattice forming step of forming a virtual lattice on the outer peripheral surface of the roller with image resolution; A vector generation step of generating a vector whose length and angle are determined by random numbers, and a processing step of processing a recess centered on the end point of the vector on the outer peripheral surface of the roller.

  According to this aspect, since the concave portion is processed centering on the end point of the vector having the length and angle determined by the random number, starting from the intersection of the virtual lattice, the outer peripheral surface corresponds to the convex shape of the surface of the image. An image surface repair roller in which a plurality of concave shapes are irregularly arranged can be manufactured. By pressing the outer peripheral surface of the image surface repair roller manufactured as described above against a scratch on the surface of the image and rotating it, the visibility of the scratch on the surface of the image can be reduced in a short time.

  ADVANTAGE OF THE INVENTION According to this invention, the visibility of the damage | wound of the surface of the image recorded by ejecting ink with the inkjet system can be reduced by a short time process.

FIG. 1 is a cross-sectional view of a sheet 1 on which a solid image is formed by an inkjet method. FIG. 2 is a diagram showing scratches 4 generated on the surface of the ink layer 3 of the paper 1. FIG. 3 is a cross-sectional view for explaining irregular reflection of the ink layer 3 and reflection at the scratch 4. FIG. 4 is a perspective view of the roller 110 with handle. FIG. 5 is a front view showing the shape of the roller portion 112. FIG. 6 is a view showing the dimple 114 on the surface of the roller portion 112. FIG. 7 is a diagram illustrating the repair of the scratch 4 by the pressing of the roller portion 112. FIG. 8 is a cross-sectional view showing the repair of the scratch 4 by the pressing of the roller portion 112. FIG. 9 is a flowchart showing a method for forming the dimple 114 on the surface of the roller portion 112. FIG. 10 is a diagram for explaining a method for forming the dimple 114. FIG. 11 is an enlarged view of FIG. FIG. 12 is an overall configuration diagram of the inkjet recording apparatus 100.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

<Scratch visual recognition mechanism>
As shown in FIG. 1, when an image (here, a solid image composed of four colors of cyan ink, magenta ink, yellow ink, and black ink) is recorded by ejecting ink onto the paper 1 by an inkjet method, the surface of the paper 1 is recorded. On the (recording surface), a plurality of granular ink droplets 2 are irregularly arranged, and an ink layer 3 in which adjacent ink droplets 2 overlap is formed. Since the surface of the ink layer 3 has irregularities formed randomly, the light irradiated on the surface of the ink layer 3 is irregularly reflected.

  FIG. 2A is a diagram illustrating an example of a scratch 4 on the surface of the ink layer 3 formed on the paper 1. The scratch 4 is a streak-like scratch generated by rubbing the ink layer 3 of the paper 1 with a minute protrusion or the like (not shown). The depth of the scratch 4 is about 1 micrometer and does not reach the paper 1. Moreover, the width | variety of the damage | wound 4 is about 10 micrometers as shown in FIG.2 (b). Even with such a minute flaw, the flaw 4 is visually recognized as an image defect, as shown in FIG.

  As shown in FIG. 3, when a scratch 4 that does not reach the paper 1 is generated on the surface of the ink layer 3, the scratch 4 serves to partially level and flatten the surface of the ink layer 3. When light is applied to the surface of the ink layer 3, the reflection behavior differs between the light applied to the scratch 4 and the light applied to the periphery of the scratch 4. The direction of light is aligned. As a result, the scratch 4 is visually recognized as an image defect. As described above, the inventor of the present application, as a result of intensive studies, the problem that the minute scratch 4 is visually recognized is not due to the change in the color of the surface of the ink layer 3, but the change in the shape of the surface of the ink layer 3. That is, it has been found that it is caused by a change in the shape of the surface of the image.

<Composition of roller with handle>
The roller with handle according to the present embodiment has a convex shape on the surface of an image recorded on the recording surface of the recording medium, and has a concave shape corresponding to the convex shape formed by ink droplets ejected by an inkjet method. Are irregularly arranged on the outer peripheral surface, and the outer peripheral surface is pressed against the scratch on the surface of the image formed by the ink droplets on the recording surface of the recording medium and is rotated to repair the scratch.

  As shown in FIG. 4, the roller with handle 110 includes a roller portion 112 (an example of an image surface repair roller), a shaft portion 116, a support portion 118, and a handle portion 120. A shaft portion 116 is press-fitted into the roller portion 112, and the roller portion 112 and the shaft portion 116 are fixed. The shaft portion 116 is rotatably supported at both ends by a support portion 118, and a handle portion 120 is fixed to the support portion 118.

  The roller portion 112 has a cylindrical shape with a diameter of 30 to 40 millimeters and an axial length of about 100 millimeters, and as shown in FIG. 5A, a central portion in a direction parallel to the shaft portion 116 (axial direction). And has a tapered shape in which the outer diameter gradually decreases toward the end. As shown in FIG. 5B, the roller portion 112 may have a straight central shape in the axial direction and a tapered shape in which the outer diameter gradually decreases toward both ends in the axial direction. As shown in FIG. 5 (c), the whole may have a straight shape with a uniform diameter.

  As shown in FIG. 6A, a plurality of dimples 114 (an example of a concave shape) are irregularly arranged on the entire outer peripheral surface of the roller portion 112. Each dimple 114 has a concave shape (an example of a concave shape corresponding to the convex shape) obtained by inverting the convex shape simulating the convex shape and size formed by the ink droplet 2 (see FIG. 1) on the surface of the image. doing.

  Here, the “convex shape formed on the surface of the image” is a portion of the ink droplets 2 ejected on the surface of the paper 1 that is not in contact with the surface of the paper 1 or other ink droplets 2. , Refers to the shape of a portion that is convex with respect to the surface, and one convex shape is formed by one ink droplet 2.

  The ink droplet 2 varies in shape and size of the convex shape after drying under various conditions. The convex shape simulating the shape and size of the convex shape here is an average ink droplet 2. The shape and size of the convex shape are assumed.

  The ink droplet 2 that has been ejected and dried on the surface of the paper 1 has a dome-shaped convex shape with a diameter of 40 micrometers and a height of 1 micrometer in a state where the ink drops 2 are arranged isolated on the paper 1. Have.

  Correspondingly, the dimple 114 is a concave portion (inverted dome shape) that is an inverted dome shape having a diameter of 40 μm and a height of 1 μm in an isolated state. By arranging the dimples 114 at a density similar to that of the ink droplets 2 on the paper 1, the outer peripheral surface of the roller portion 112 is formed into a concave shape obtained by inverting the “convex shape and size formed on the surface of the image”. Can do. Therefore, the “concave shape obtained by inverting the shape and size of the convex shape formed on the surface of the image” is the shape of the concave portion with respect to the roller portion 112, and one concave shape corresponding to one convex shape. It has a shape.

  The arrangement density of the plurality of dimples 114 is the arrangement density of the ink droplets 2 on the surface of the ink layer 3 when an image (for example, a 4C solid image) having a coverage of 100% or more on the paper 1 is recorded. It is the same. The plurality of dimples 114 are irregularly arranged corresponding to the plurality of ink droplets 2 and are formed so as to partially overlap the dimples 114 adjacent to each other. As a result, in each dimple 114, the opening edges of the dimples 114 adjacent to each other are arranged in an irregular shape.

  FIG. 6B is a cross-sectional view taken along the line bb of FIG. As shown in the figure, the outer peripheral surface of the roller portion 112 has irregularities that are inverted from the irregularities that simulate the shape and size of the irregularities on the surface of the image recorded on the paper 1.

<Image surface restoration method using a roller with handle>
A sheet 1 shown in FIGS. 7A and 8A is a target printed matter of the roller 110 with a handle on which an image is recorded by an inkjet method, and the surface is irregularly arranged with a coverage of 100% or more. An ink layer 3 is formed by a plurality of ink droplets 2. In addition, streak-like scratches 4 are generated on the surface of the ink layer 3.

  The user detects this scratch 4 by visual observation or by a detection device (not shown) (an example of a detection process).

  The user holds the handle portion 120 (see FIG. 4) of the roller 110 with a handle on the sheet 1, and the outer peripheral surface of the roller portion 112 is removed as shown in FIGS. 7B and 8B. The roller portion 112 is rotated and pressed against the surface of the ink layer 3 with a constant pressure (an example of a rotation and travel process). Here, the rotational travel refers to a state in which the outer peripheral surface of the roller portion 112 is in pressure contact with the surface of the ink layer 3 and the roller portion 112 is rotated to sequentially travel while changing the pressure contact position. The force with which the user presses the outer peripheral surface of the roller portion 112 of the roller with handle 110 against the surface of the ink layer 3 is 30 N (Newton) in a direction perpendicular to the surface of the ink layer 3 as a guide.

  Note that the length of the roller portion 112 in the direction parallel to the shaft portion 116 is shorter than the vertical length and the horizontal length of the recording surface of the paper 1. Therefore, the roller unit 112 rotates and travels locally in an area including the scratch 4 on the recording surface of the paper 1. Further, it is not necessary to rotate the entire surface of the paper 1. Here, the roller portion 112 is rotated in a direction parallel to the direction in which the scratch 4 extends, but the traveling direction of the roller portion 112 may not be parallel to the direction in which the scratch 4 extends.

  FIGS. 7C and 8C show the ink layer 3 in which the scratch 4 has been repaired by the pressing travel of the roller portion 112, and the region A and the region A where the roller portion 112 has been pressed and traveled are shown. , The other area B is shown.

  As shown in the figure, the visibility of the scratch 4 is reduced. The area A where the roller 112 is pressed has the same shape and size as the unevenness of the ink layer 3 before pressing the roller 112 (the surface of the ink layer 3 shown in FIG. 7A). Since the unevenness is formed, the area A where the roller part 112 is pressed and the other area B have the same reflectance. Accordingly, the light irradiated onto the paper 1 is diffusely reflected in the areas A and B in the same manner, and the area A against which the roller portion 112 is pressed is not visually recognized as unevenness.

  As described above, according to the roller 110 with a handle according to the present embodiment, the portion of the surface of the ink layer 3 is not visually recognized as a non-uniform portion by pressing the roller portion 112 due to a short time of rotation rotation. The visibility of the wound 4 can be reduced by repairing the wound 4. In addition, since the scratch 4 is repaired by the pressing travel of the roller portion 112, it can be repaired regardless of the length of the scratch 4. Furthermore, since the roller portion 112 has a tapered shape, the boundary between the region where the roller portion 112 is pressed and the region where the roller portion 112 is not pressed can be made ambiguous, and the roller portion 112 is pushed by the viewer of the image. It is possible not to recognize the applied area.

  When the ink layer 5 similar to the ink layer 3 is formed on the back surface of the paper 1, the surface shape of the surface that supports the back surface of the paper 1 is changed by the roller portion 112. There is a possibility of being transferred to the ink layer 5 on the back surface of the pressed portion. In this case, a number of dimples similar to the outer peripheral surface of the roller unit 112 may be provided on the surface that supports the back surface of the paper 1.

<Other aspects of image surface repair method>
Here, a mode has been described in which the sheet 1 is fixed and the outer peripheral surface of the roller unit 112 is pressed against the surface of the ink layer 3 and the roller unit 112 is rotated and sequentially moved while changing the press contact position. 4 can be repaired by rotating the paper 1 and the roller portion 112 relatively.

  For example, the position of the roller part 112 is fixed, a nip roller (not shown) facing the roller part 112 is provided, and the scratch 4 presses the outer peripheral surface of the roller part 112 between the roller part 112 and the nip roller (not shown). The roller unit 112 may be rotated so as to be applied, and the paper 1 may be caused to travel. In this case, the nip roller (not shown) has the same configuration as that of the roller unit 112, so that the portion where the nip roller (not shown) is pressed on the back surface of the paper 1 is not visually recognized as unevenness.

  In addition, the roller unit 112 is made larger than the sheet 1, and the sheet 1 is rotated on the outer peripheral surface of the roller unit 112 while sequentially changing the pressure contact position. The sheet 1 is moved and the roller unit 112 is rotated. A mode in which the paper 1 and the roller unit 112 are rotated while sequentially changing the press-contact position is also possible.

<Roller part manufacturing method>
The roller part 112 can be manufactured by forming a large number of dimples 114 on the surface of a ceramic roller by laser processing, for example. A method for forming the dimple 114 on the surface of the roller portion 112 for repairing the scratch 4 on the target printed matter will be described with reference to FIGS. 9, 10, and 11.

  First, a virtual lattice 130 is formed on the surface of the roller portion 112 (step S1: an example of a lattice forming step). FIG. 10A shows a part of the grating 130, and here, a grating having a vertical and horizontal interval of 15 micrometers is used. The interval between the grids 130 is the same as the reciprocal of the recording resolution of the target printed matter.

  Next, a vector (r, θ) of length r and angle θ is generated starting from each intersection of the grid 130 (step S2: an example of a vector generation step). Here, the length r is determined by a random number having a minimum value of 0 μm, a maximum value of 4 μm, and a resolution of 1 μm, and the angle θ is a minimum value of 0 degrees, a maximum value of 359 degrees, and a resolution of 1 Determined by a random number of degrees. Note that the angle θ is a counterclockwise angle with respect to the horizontal right direction of the intersection of the lattice 130.

FIG. 10B shows a vector 134a starting from the intersection 132a, a vector 134b starting from the intersection 132b, a vector 134c starting from the intersection 132c, and a vector 134d starting from the intersection 132d. Further, as shown in FIG. 11, the vector 134a is a vector with a length r _a and an angle θ _a (r _a , θ _a ), and the vector 134b is a vector with a length r _b and an angle θ _b (r _b , θ _b ). , Vector 134c is a vector (r _c , θ _c ) of length r _c and angle θ _c , and vector 134d is a vector (r _d , θ _d ) of length r _d and angle θ _d .

  Finally, a dimple having a concave shape with the convex shape formed by the ink droplet 2 on which the target printed matter is recorded around the end point of each vector is formed (step S3: an example of a processing step). Here, laser processing is carried out into an inverted dome shape, centering on the end points 136a, 136b, 136c, and 136d of each vector, with a diameter of 30 micrometers and a depth of 1 micrometer as processing target values.

  FIG. 10 (c) shows circles 138a, 138b, 138c, and 138d with a diameter of 30 micrometers (radius 15 micrometers) centered on the end points 136a, 136b, 136c, and 136d, and FIG. Shows the dimples 114a, 114b, 114c, and 114d formed by laser processing each of the circles 138a, 138b, 138c, and 138d into an inverted dome shape.

  By performing this process on all the intersections of the lattice 130 virtually formed on the entire surface of the roller portion 112, a large number of dimples 114 can be formed in an irregular arrangement on the surface of the roller portion 112.

  As described above, in this embodiment, the dimple 114 is irregularly arranged by determining the position to be the center of the dimple 114 using a random number. Note that the processing of steps S1 to S3 may be performed in a certain range on the surface of the roller portion 112, and the arrangement of the dimples 114 in this certain range may be repeatedly formed in other regions on the surface of the roller portion 112. Even when such processing is performed, the dimples 114 are irregularly arranged.

  In forming the dimple 114, the diameter of the dimple 114n processing target value may be determined by a random number. For example, it can be determined by a random number having a minimum value of 29 micrometers, a maximum value of 31 micrometers, and a resolution of 0.5 micrometers.

<Overall configuration of image recording apparatus>
Next, an ink jet recording apparatus that prints a target printed material for which the roller with handle 110 repairs the scratch 4 will be described.

  The ink jet recording apparatus 100 is a sheet-fed ink jet printing machine that prints an image on a sheet of paper (hereinafter referred to as paper), which is a sheet recording medium, and uses water-based ink especially for general-purpose printing paper. This is a sheet-fed color ink jet printer that performs color printing.

  General-purpose printing paper is not so-called inkjet paper but cellulose such as coated paper (art paper, coated paper, lightweight coated paper, cast paper, fine coated paper, etc.) used in offset printing, etc. This is a paper mainly composed of Further, the water-based ink refers to an ink in which a coloring material such as a dye or a pigment is dissolved or dispersed in water and a water-soluble solvent.

  As shown in FIG. 12, the inkjet recording apparatus 100 mainly includes a paper feeding unit 10 that feeds the paper 1 and a processing liquid application unit that applies a predetermined processing liquid to the paper 1 fed from the paper feeding unit 10. 20, a processing liquid drying unit 30 for drying the paper 1 coated with the processing liquid, an image recording unit 40 for recording an image on the dried paper 1 by an inkjet method, and the paper 1 on which the image is recorded. An ink drying unit 50 that performs drying processing and a stacking unit 60 that stacks the dried paper 1 are configured.

[Paper Feeder]
The paper feeding unit 10 feeds the paper 1 one by one. As shown in FIG. 12, the paper feeding unit 10 mainly includes a paper feeding device 12, a feeder board 14, a front pad 15, and a paper feeding drum 16.

  The sheet feeding device 12 takes out the sheets 1 set in a predetermined position in a bundle of sheets one by one in order from the top, and feeds the sheets one by one to the feeder board 14.

  The feeder board 14 is formed so as to correspond to the width of the paper 1, and the front end side is inclined downward. The feeder board 14 guides the sheet 1 fed from the sheet feeding device 12 to the front pad 15 by sliding along the transport surface.

  The front pad 15 is a plate-like member arranged orthogonal to the conveyance direction of the paper 1 and is provided so as to be swingable by being driven by a motor (not shown). The front pad 15 swings to correct the posture of the paper 1 and transfers the paper 1 whose posture has been corrected to the paper supply drum 16.

  The paper supply drum 16 receives the paper 1 from the front pad 15, transports it along a predetermined transport path, and delivers it to the processing liquid coating unit 20. The paper supply drum 16 has a cylindrical shape, and grips and rotates the front end of the paper 1 in the transport direction with a gripper 17 provided on the peripheral surface, thereby winding the paper 1 around the peripheral surface and transporting it.

[Treatment liquid application part]
The treatment liquid application unit 20 applies a predetermined treatment liquid to the image recording surface of the paper 1 while conveying the paper 1. The treatment liquid applied by the treatment liquid application unit 20 is a liquid having a function of aggregating, insolubilizing or increasing the viscosity of the color material component in the ink. By applying such a treatment liquid to paper, high-quality images can be recorded even when images are recorded on general-purpose printing paper by an inkjet method.

  As shown in FIG. 12, the treatment liquid application unit 20 mainly applies a treatment liquid application drum 22 that conveys the paper 1 and a treatment liquid that is applied to the image recording surface of the paper 1 that is conveyed by the treatment liquid application drum 22. And a liquid application device 24.

  The treatment liquid application drum 22 receives the paper 1 from the paper supply drum 16 of the paper supply unit 10, conveys the received paper 1 along a predetermined conveyance path, and delivers it to the treatment liquid drying unit 30. The treatment liquid coating drum 22 has a cylindrical shape, and grips and rotates the front end of the paper 1 in the transport direction with a gripper 23 provided on the peripheral surface, whereby the paper 1 is wound around the peripheral surface and transported. . The sheet 1 is conveyed by being wound around the peripheral surface of the treatment liquid coating drum 22 with the image recording surface facing outward.

  The processing liquid application device 24 applies the processing liquid to the image recording surface of the paper 1. In the present embodiment, a treatment liquid is applied by pressing a roller (application roller) having a treatment liquid applied to the peripheral surface thereof against the image recording surface of the sheet 1 conveyed by the treatment liquid application drum 22. Note that the method of applying the treatment liquid is not limited to this, and a method of applying using an inkjet head, a method of applying using a spray, or the like can also be employed.

  The treatment liquid application unit 20 is configured as described above. The processing liquid is applied to the image recording surface of the paper 1 by the processing liquid coating device 24 in the process of being conveyed by the processing liquid coating drum 22.

[Processing liquid drying section]
The treatment liquid drying unit 30 dries the paper 1 while conveying the paper 1 coated with the treatment liquid. The treatment liquid drying unit 30 mainly includes a treatment liquid drying drum 32 that conveys the paper 1, and a treatment liquid drying device 34 that blows warm air on the paper 1 conveyed by the treatment liquid drying drum 32 to dry the paper 1. And comprising.

  The treatment liquid drying drum 32 receives the paper 1 from the treatment liquid application drum 22 of the treatment liquid application unit 20, conveys the received paper 1 along a predetermined conveyance path, and delivers it to the image recording unit 40. The treatment liquid drying drum 32 is configured by a frame body assembled in a cylindrical shape, and conveys the sheet 1 by gripping and rotating the front end of the sheet 1 with a gripper 33 provided on the peripheral surface. .

  The treatment liquid drying device 34 is installed inside the treatment liquid drying drum 32, and blows warm air toward the paper 1 conveyed by the treatment liquid drying drum 32.

  The treatment liquid drying unit 30 is configured as described above. In the course of being conveyed by the treatment liquid drying drum 32, the paper 1 is dried by spraying hot air onto the treatment liquid application surface by the treatment liquid drying device 34.

(Image recording part)
The image recording unit 40 records a color image on the image recording surface of the paper 1 by an ink jet method using four colors of cyan, magenta, yellow, and black while conveying the paper 1. As shown in FIG. 12, the image recording unit 40 mainly presses the image recording drum 42 that conveys the paper 1 and the paper 1 conveyed by the image recording drum 42 against the peripheral surface of the image recording drum 42. A color image is recorded on the paper 1 by ejecting C, M, Y, and K ink droplets toward the paper 1 conveyed by the image recording drum 42, and a pressing roller 44 that closely contacts 1 to the image recording drum 42. And a scanner 47 that reads an image recorded on the paper 1.

  The image recording drum 42 is an example of a conveying unit. The image recording drum 42 receives the paper 1 from the treatment liquid drying drum 32 of the treatment liquid drying unit 30, conveys the received paper 1 along a predetermined conveyance path, and delivers it to the ink drying unit 50. The image recording drum 42 has a cylindrical shape, and grips and rotates the leading edge of the paper 1 with a gripper 43 provided on the peripheral surface, whereby the paper 1 is wound around the peripheral surface which is a paper holding surface and conveyed.

  Further, the image recording drum 42 is provided with a suction mechanism for fixing the paper 1 being conveyed on the drum. In the image recording drum 42 of the present embodiment, the sheet 1 is adsorbed using negative pressure. The image recording drum 42 has a plurality of suction holes on the peripheral surface which is a paper holding surface, and sucks and fixes the paper 1 by suction from the inside of the drum through the suction holes.

  The pressing roller 44 is an example of a pressing unit. The pressing roller 44 presses the paper 1 conveyed by the image recording drum 42 against the peripheral surface of the image recording drum 42, thereby bringing the paper 1 into close contact with the image recording drum 42. The pressing roller 44 is a rubber roller having a width corresponding to the image recording drum 42. The pressure roller 44 is disposed immediately after the position where the image recording drum 42 receives the paper 1 from the treatment liquid drying drum 32. As a result, the sheet 1 is wound around the circumferential surface of the image recording drum 42 while being pressed against the circumferential surface of the image recording drum 42 by the pressing roller 44.

  The head unit 45 ejects cyan ink droplets by an inkjet method, an inkjet head 46M that ejects magenta ink droplets, an inkjet head 46Y that ejects yellow ink droplets, and a black ink droplet. And an inkjet head 46K. Here, as the inkjet heads 46C, 46M, 46Y, and 46K of the inkjet system, the piezo system that deforms the piezoelectric element and ejects ink droplets, or the pressure of bubbles generated by heating the ink with a heating element is used. Various types of inkjet heads such as a thermal jet method for ejecting droplets can be applied.

  Each of the inkjet heads 46C, 46M, 46Y, and 46K is composed of a line head capable of recording an image in a single pass with respect to the paper 1 conveyed by the image recording drum 42. Arranged on the transport path. Each of the inkjet heads 46C, 46M, 46Y, and 46K has a nozzle surface at the tip, and ejects ink droplets from the nozzles arranged on the nozzle surface toward the paper 1 conveyed by the image recording drum 42.

  Each nozzle of each of the inkjet heads 46C, 46M, 46Y, and 46K is configured to be able to eject ink droplets of small droplet amount, medium droplet amount, and large droplet amount having different droplet ejection amounts (volumes). The small droplet amount of ink droplet is a droplet ejection amount mainly used in a low duty portion (light color portion) of the recorded image, and the medium droplet amount of ink droplet is a high duty portion of the recorded image. This is the droplet ejection amount mainly used in the portion (the dark portion). The large drop amount is for increasing the drop amount of the nozzle adjacent to the clogged nozzle to compensate for the clogged nozzle, and is not normally used.

  As shown in FIG. 12, the scanner 47 is installed on the downstream side of the head unit 45 with respect to the conveyance direction of the paper 1 by the image recording drum 42. The scanner 47 reads an image recorded on the paper 1 by the head unit 45.

  The image recording unit 40 is configured as described above. In the sheet 1, ink droplets of each color of C, M, Y, and K from the inkjet heads 46 C, 46 M, 46 Y, and 46 K constituting the head unit 45 in the process of being conveyed by the image recording drum 42 are on the image recording surface. As a result, a color image is recorded on the image recording surface. The image recorded on the paper 1 is read by the scanner 47 as necessary.

[Ink drying section]
The ink drying unit 50 performs the drying process while transporting the sheet 1 immediately after the image recording by the image recording unit 40. As shown in FIG. 12, the ink drying unit 50 is mainly transported by the chain gripper 52 that transports the paper 1, the paper guide 54 that guides the travel of the paper 1 transported by the chain gripper 52, and the chain gripper 52. And a heating / drying device 56 that heats and dries the image recording surface of the paper 1 to be printed.

  The chain gripper 52 receives the sheet 1 from the image recording drum 42 of the image recording unit 40, conveys the received sheet 1 along a predetermined conveyance path, and discharges it to the stacking unit 60. The chain gripper 52 includes an endless chain 52A that travels along a certain travel route, and grips the vicinity of the leading edge of the paper 1 with the gripper 52B provided in the chain 52A to transport the paper 1. The paper 1 passes through the heating area and the non-heating area set in the ink drying unit 50 by being conveyed to the chain gripper 52. The heating area is set to an area where the paper 1 transferred from the image recording unit 40 is first transported horizontally, and the non-heating area is set to an area where the paper 1 is transported in an inclined manner.

  The paper guide 54 is disposed along the transport path of the paper 1 by the chain gripper 52 and guides the travel of the paper 1 transported by the chain gripper 52. The paper guide 54 includes a first guide board 54A and a second guide board 54B.

  The first guide board 54A is a guide board disposed in the heating region, and has a hollow flat plate shape. The first guide board 54A has an upper surface portion as a guide surface of the paper 1, and the paper 1 is conveyed while sliding on the guide surface.

  A number of suction holes (not shown) are provided on the guide surface of the first guide board 54A. The first guide board 54A guides the travel of the paper 1 while sucking the paper 1 against the guide surface by sucking negative pressure from the inside through the suction holes.

  The first guide board 54A is provided with a cooling mechanism (not shown) for cooling the guide surface. The cooling mechanism is constituted by, for example, a water-cooling type cooling mechanism, and cools the guide surface by flowing a cooling liquid through a flow path disposed inside. The first guide board 54A uses the cooling mechanism to control the temperature of the guide surface to a constant temperature.

  The second guide board 54B is a guide board disposed in the non-heated area. The configuration of the second guide board 54B is the same as the configuration of the first guide board 54A. That is, it has a hollow flat plate shape and guides the travel of the paper 1 while sucking the paper 1 to the guide surface by a suction hole (not shown). Further, a cooling mechanism (not shown) is provided, and the temperature of the guide surface is controlled to a constant temperature.

  The heating and drying device 56 is installed in the heating area, and heats and dries the image recording surface of the paper 1 conveyed through the heating area with radiant heat from a heat source. The heating / drying device 56 includes a plurality of infrared lamps 56 </ b> A as heat sources, and is disposed inside the chain gripper 52. The infrared lamps 56A are arranged at regular intervals along the conveyance path of the paper 1 in the heating area.

  The ink drying unit 50 is configured as described above. In the course of being conveyed by the chain gripper 52, the sheet 1 is heated and dried by the heating and drying device 56 on the image recording surface.

[Accumulator]
The stacking unit 60 stacks the sequentially discharged sheets 1 at one place. As shown in FIG. 12, the stacking unit 60 mainly includes a stacking device 62 that receives and stacks the paper 1 conveyed from the ink drying unit 50 by the chain gripper 52.

  The chain gripper 52 releases the grip 1 by releasing the gripper 52B at a predetermined stacking position. The stacking device 62 collects the released sheets 1 and stacks them in a bundle.

  In the ink jet recording apparatus 100, the image can be recorded on the back surface of the paper 1 by reversing the front and back surfaces of the paper 1 on which the image is recorded on the front surface and setting the paper 1 again in the paper feeding unit 10. During the backside printing, in the process of transporting the paper 1, scratches 4 may occur on the image (the formed ink layer 3) recorded on the front surface of the paper 1.

  In the inkjet recording apparatus 100 configured as described above, the target printed matter of the roller with handle 110 is printed. When the scratch 4 is generated on the surface of the image of the target printed matter, the user can repair the scratch 4 using the roller 110 with a handle.

  Here, it is a high-duty image in which the scratches 4 on the paper 1 appear prominently. Further, the inkjet recording apparatus 100 records a high duty image using a medium amount of ink droplets. Accordingly, the dimple 114 of the roller portion 112 of the roller 110 with handle is formed in a concave shape that is a reverse of the convex shape that simulates the shape and size of the convex shape that the medium droplet amount of ink droplet forms on the surface of the image. The visibility of the scratch 4 can be appropriately reduced.

  In the ink jet recording apparatus 100 according to the present embodiment, the medium droplet amount of each of the ink jet heads 46C, 46M, 46Y, and 46K is 7 picoliters of the average droplet ejection amount and 40 micrometers of the average ink droplet diameter. is there. Therefore, an appropriate dimple 114 can be formed by processing a recess having a diameter of 40 micrometers in the roller portion 112.

  Note that there is a fixed relationship between the amount of ink droplets ejected in the ink jet recording apparatus and the size (diameter) of the ink droplets on the printed matter. Accordingly, a roller set including a plurality of roller portions 112 having dimples 114 having a size corresponding to the droplet ejection amount when the target printed matter is printed may be configured for each droplet ejection amount. Thereby, the user of the ink jet recording apparatus 100 can repair the scratch 4 using the roller portion 112 on which the appropriate dimple 114 is formed according to the amount of ink droplets 2 ejected in the ink jet recording apparatus 100. it can.

  The technical scope of the present invention is not limited to the scope described in the above embodiment. The configurations and the like in the embodiments can be appropriately combined between the embodiments without departing from the gist of the present invention.

  DESCRIPTION OF SYMBOLS 1 ... Paper, 2 ... Ink droplet, 3 ... Ink layer, 4 ... Scratch, 46C, 46M, 46Y, 46K ... Inkjet head, 100 ... Inkjet recording apparatus, 110 ... Roller with handle, 112 ... Roller part, 114 ... Dimple, 116 ... Shaft part, 118 ... Support part, 120 ... Handle part

Claims (11)

  A plurality of concave shapes corresponding to the convex shape of the surface of the image recorded on the recording surface of the recording medium and corresponding to the convex shape formed by the ink droplets ejected by the ink jet method are irregularly arranged on the outer peripheral surface. Image surface repair roller.   The image surface repair roller according to claim 1, wherein the concave shape is a shape obtained by inverting the shape and size of the convex shape of the surface of the image.   3. The image surface repair roller according to claim 1, wherein the concave shapes are arranged such that edges of the concave shapes adjacent to each other are irregularly shaped. 4.   4. The image surface repair roller according to claim 1, wherein the concave shape is a shape obtained by inverting a convex shape and a size corresponding to a volume of the ink droplet. 5.   The image surface repair roller according to claim 1, wherein the entire outer peripheral surface has the concave shape.   6. The image surface repair roller according to claim 1, wherein a diameter of the image surface repair roller gradually decreases from an axial center to both ends of the image surface repair roller.   The image surface repair roller according to claim 6, wherein a length of the image surface repair roller in an axial direction is shorter than a longitudinal length and a lateral length of a recording surface of the recording medium. A support portion for rotatably supporting the image surface repair roller;
A handle that is fixed to the support and is gripped by a user;
An image surface repair roller according to any one of claims 1 to 7, further comprising: A roller set comprising a plurality of image surface repair rollers according to any one of claims 1 to 8,
The plurality of image surface repair rollers are roller sets in which a plurality of concave shapes corresponding to the convex shapes formed by the ink droplets having different volumes are irregularly arranged. A detection step of detecting scratches on the surface of an image recorded on a recording surface of a recording medium and formed by ink droplets ejected by an inkjet method;
A convex shape on the surface of the image, wherein an outer peripheral surface of an image surface repair roller in which a plurality of concave shapes corresponding to the convex shape formed by the ink droplets are irregularly arranged on the outer peripheral surface is pressed against the scratch. A rotating travel step of relatively rotating the recording medium and the image surface repair roller;
An image surface repair method comprising: A plurality of concave shapes corresponding to the convex shape of the surface of the image recorded on the recording surface of the recording medium and corresponding to the convex shape formed by the ink droplets ejected by the ink jet method are irregularly arranged on the outer peripheral surface. In the manufacturing method of the image surface repair roller,
A grid forming step of forming a virtual grid at the resolution of the image on the outer peripheral surface of the roller;
A vector generation step of generating a vector whose length and angle are determined by random numbers, starting from the intersection of the grids;
A processing step of processing a recess centered on the end point of the vector on the outer peripheral surface of the roller;
A method of manufacturing an image surface repair roller comprising: