JP5736358B2 - Letterpress for printing, letterpress making apparatus for printing, letterpress making method for printing, printing apparatus, printing method, printing pressure determination apparatus, and printing pressure determination method - Google Patents

Description

  The present invention relates to a printing relief plate provided on the surface of a plate material and having protrusions for transferring ink to a printing medium to print halftone dots. The present invention also relates to a printing relief plate producing apparatus and a printing relief plate producing method for producing the printing relief plate. Furthermore, the present invention relates to a printing apparatus and a printing method for printing halftone dots by transferring ink from the printing relief plate to a printing medium. Furthermore, the present invention provides a printing pressure determination device that determines whether or not the magnitude of the printing pressure applied to the printing relief plate is an appropriate printing pressure when transferring ink from the printing relief plate to the printing medium. And a printing pressure determination method.

  For example, in flexographic printing, a printing relief plate made of a flexible and elastic plate material is attached to the surface of the plate cylinder, and the surface of the printing relief plate (plate surface) is transferred to a substrate by printing ink. Protrusions for printing dots are formed. Here, when ink is supplied from the anilox roller to the printing plate while the printing substrate is held between the plate cylinder and the impression cylinder, the ink is transferred from the printing plate to the printing substrate, and a halftone dot is formed on the printing substrate. Can be printed. As a result, a desired image can be transferred (printed) to the printing medium.

  In this case, the printing condition of the printing medium is determined by adjusting the pressure between the anilox roller and the printing plate (ani pressure) and the pressure between the printing plate and the printing medium (printing pressure). The printing pressure is preferably as low as possible (minimum pressure required to transfer the entire image satisfactorily) in order to transfer the entire image (picture) onto the printing medium.

  In Patent Document 1, when a detection part lower than the image line part as the protrusion part is formed on the printing plate, and the ink of the detection part is transferred to the printing medium, excessive printing pressure (hereinafter also referred to as overprinting pressure). )) Is disclosed as a technique for determining whether it is on the printing plate.

  Patent Documents 2 and 3 disclose that the printing pressure is adjusted based on the line width or density of the linear portion printed on the printing medium.

  Further, Patent Document 4 inspects the quality of the printing relief plate by transferring the ink from the quality confirmation convex portion formed on the printing plate to the printing material and confirming the image transferred to the printing material. It is disclosed.

Japanese Patent No. 4682855 JP-A-2-9635 JP 2009-881 A JP 2002-137558 A

  The technique of Patent Document 1 is based on the premise that ink is supplied to the detection unit. On the other hand, the ink is transferred from the anilox roller to the printing plate with an ani pressure such that the ink is supplied to the lowest portion of the image area (the lowest protrusion when a plurality of protrusions are formed). It must be a necessary condition. Therefore, the ink is not necessarily supplied to the detection unit that is lower than the image line unit.

  Therefore, in the technique of Patent Document 1, in a state where ink is not supplied to the detection unit, when the printing body is sandwiched between the plate cylinder and the impression cylinder and the ink attached to the plate surface is transferred to the printing body, Since the ink does not transfer from the detection unit to the printing medium, printing is performed at an optimum printing pressure (hereinafter also referred to as appropriate printing pressure) even if the printing pressure is excessive. There is a problem of misjudging it. Further, Patent Documents 2 to 4 do not disclose a technique for solving the above problem.

  The present invention has been made in consideration of such problems, and it is possible to easily determine whether the printing pressure is the appropriate printing pressure or the overprinting pressure regardless of the condition of the ani pressure. An object of the present invention is to provide a printing relief plate. Another object of the present invention is to provide a printing relief plate producing apparatus and a printing relief plate producing method capable of producing such a relief printing plate. Furthermore, an object of this invention is to provide the printing apparatus and printing method which can print a to-be-printed body using the said relief printing plate. Furthermore, the present invention provides a printing method that can easily determine whether the printing pressure is an appropriate printing pressure or an overprinting pressure based on an image printed on a printing medium using the printing relief plate. An object is to provide a pressure determination device and a printing pressure determination method.

  The present invention relates to a printing relief plate provided on the surface of a plate material and having protrusions for transferring halftone dots by transferring ink to a printing medium.

  And the relief printing plate concerning this invention has the following structure in order to achieve said objective.

  That is, on the surface of the plate material, a solid portion, an image line forming region in which a plurality of the protrusions are formed, and the printing relief plate when ink is transferred from the printing relief plate to the printing medium. A detection unit for determining the magnitude of the printing pressure is provided, and the detection unit and the highlight projection that is lower than the solid unit and the lowest among the projections have substantially the same height. Is set.

  Further, the density of the detection unit image printed on the printing medium by the transfer of ink from the detection unit to the printing medium, and the printing medium by the transfer of ink from the solid part to the printing medium. By comparing with the density of the solid image to be printed, it can be determined whether or not the printing pressure is an appropriate printing pressure.

  As described above, in the relief printing plate according to the present invention, the lowest protrusion (the highlight protrusion) and the detection part are set to have substantially the same height. Therefore, for example, even if the ani pressure is set to the lowest pressure that matches the printing conditions of the substrate, ink can be supplied to the highlight protrusion and the detection portion having substantially the same height. In addition, the detection part image can be printed by reliably transferring the ink adhering to the detection part to the printing medium. Therefore, by comparing the density of the detection part image and the density of the solid part image, it is easy to determine whether the printing pressure is an appropriate printing pressure or an overprinting pressure regardless of the magnitude of the ani pressure. Can be determined.

  In order to produce such a relief printing plate according to the present invention, the relief printing plate production apparatus and the relief printing plate production method may be configured as follows.

  That is, the printing relief printing plate creation apparatus according to the present invention is a device for creating the printing relief printing plate, and generates binary image data based on multi-value image data representing a printing image. A plate shape determining unit that generates shape data indicating each shape of the solid part, the image forming region including the protrusions, and the detection unit based on the binary image data; A printing letterpress creating unit for creating the printing letterpress based on the shape data.

  Further, the printing relief plate producing method according to the present invention is a method for producing the printing relief plate, wherein the binary image data is generated based on the multi-value image data representing the print image; Generating shape data indicating each shape of the solid portion, the image forming area including the protrusions, and the detection unit based on the value image data; and the printing based on the shape data Creating a relief letterpress.

  On the other hand, a printing apparatus and a printing method for performing printing on the printing medium using the printing relief plate according to the present invention may be configured as follows.

  That is, the printing device according to the present invention is a device that prints the halftone dots on the printing medium using the printing relief plate, the anilox roller, and the printing relief plate is attached to the anilox roller from the anilox roller. Ink is transferred from the protrusions to the printing body by sandwiching the printing body in cooperation with a printing cylinder to which ink is transferred to the printing relief plate and the printing cylinder to which the printing relief plate is attached. And an impression cylinder for transferring the halftone dots on the substrate.

  The printing method according to the present invention is a method of printing the halftone dots on the substrate using the printing relief plate, and transferring ink from the anilox roller to the printing relief plate attached to the plate cylinder. And transferring the ink from the protrusions to the printing body in a state where the printing body is sandwiched between the plate cylinder and the impression cylinder to which the printing relief plate is attached, to the printing body. Printing the halftone dots.

  Then, based on the detection part image and the solid part image printed on the substrate using the relief printing plate according to the present invention, whether the printing pressure is the appropriate printing pressure or the overprinting pressure Therefore, the printing pressure determination device and the printing pressure determination method may be configured as follows.

  That is, the printing pressure determination device according to the present invention is a device that determines the magnitude of the printing pressure applied to the printing relief plate when printing halftone dots on the printing material, wherein the detection unit image and the detection unit Based on a comparison between the imaging unit that captures the solid image and the density of the detection unit image captured by the imaging unit and the density of the solid image, it is determined whether or not the printing pressure is an appropriate printing pressure. A determination unit.

  Further, the printing pressure determination method according to the present invention is a method for determining the magnitude of printing pressure applied to the printing relief plate when printing halftone dots on the printing material, wherein the detection unit image and the detection unit Capturing a solid image, and determining whether or not the printing pressure is an appropriate printing pressure based on a comparison between the density of the captured detection image and the density of the solid image.

  Since the above-described printing relief creating apparatus, printing relief creating method, printing apparatus, printing method, printing pressure determination apparatus, and printing pressure determination method are all apparatuses or methods related to the printing relief plate according to the present invention. The effects of the relief printing plate can be obtained.

  And it is preferable that this invention further has the structure of following [1]-[5].

  [1] If the density of the detection part image is lower than the density of the solid part image, it is determined that the printing pressure is appropriate. On the other hand, the density of the detection part image and the density of the solid part image Are substantially equal, it is preferable to determine that the printing pressure is an overprinting pressure.

  The solid portion is a portion which is substantially flat and has a certain area or more in the printing relief plate, and is formed at a position higher than other portions constituting the printing relief plate.

  Therefore, when the printing pressure is an appropriate printing pressure, the printing surface of the printing relief plate is in a kiss-touch state with respect to the printing material, and the ink is firmly transferred from the solid portion to the printing material. The ink is transferred from the detection unit to the printing medium with a light touch. In this case, the density of the solid image is approximately 100% (the density of the filled image without halftone dots), and the density of the detection image is sufficiently lower than that of the solid image.

  On the other hand, if the printing pressure is an overprinting pressure, ink is firmly transferred from the detection unit to the printing medium, so that the density of the detection unit image is substantially equal to the density of the solid image.

  Therefore, in the present invention, as described above, it is possible to easily determine whether or not the printing pressure is an overprinting pressure by comparing the density of the detection unit image and the density of the solid image. Can do.

  [2] It is preferable that the detection unit is a recess formed in the solid portion, and the height position of the bottom surface of the recess and the height position of the top portion of the highlight protrusion are substantially equal. As a result, the ink supplied from the anilox roller can be stored in the recess, and the stored ink can be reliably transferred to the printing medium.

  [3] If at least the top of the highlight protrusion is formed as a flat portion, the quality of the image (halftone dot) formed by the ink transferred from the highlight protrusion to the printing medium is improved. Can be improved.

  [4] If the detection unit is at the same height as the highlight protrusion or slightly higher than the highlight protrusion, the above-described effects can be easily obtained. Of course, even when the protrusions are set at the same height as the highlight protrusions, the above-described effects can be obtained.

  [5] A plurality of the detection portions are formed on the surface of the plate material, and a plurality of the detection portion images are printed on the printing body by transferring ink from the detection portions to the printing body. May be. In this case, the density of each detection unit image is compared with the density of the solid image, and the majority of the number of detection unit images according to the appropriate printing pressure and the number of detection unit images according to the overprinting pressure are determined. By the above, it may be determined whether the printing pressure is the appropriate printing pressure or the overprinting pressure.

  The relief printing plate as a whole may have some degree of height variation (height distribution). Therefore, a plurality of the detection units are provided, and the printing pressure is determined by the majority determination based on the comparison result between the density of each detection unit image corresponding to each detection unit and the density of the solid image, or the appropriate printing pressure or If it is determined which of the overprinting pressures, the influence of the height variation of each detection unit on the determination result of the printing pressure is suppressed, and the determination of the appropriate printing pressure or the overprinting pressure is performed with high accuracy. It can be carried out.

  In the above description, the case has been described in which it is automatically determined whether the printing pressure is the appropriate printing pressure or the overprinting pressure by the printing pressure determination device and the printing pressure determination method. In the present invention, the operator can visually determine whether the printing pressure is the appropriate printing pressure or the overprinting pressure based on the comparison between the density of the detection unit image and the density of the solid image. It is also possible to determine whether the printing pressure is the appropriate printing pressure or the overprinting pressure by comparing the density of the image and the density of the solid image.

  According to the present invention, the lowest protrusion (highlight protrusion) and the detection part are set at substantially the same height. Therefore, for example, even if the ani pressure is set to the lowest pressure that matches the printing condition of the printing medium, ink can be supplied to the highlight protrusion and the detection unit having substantially the same height, The ink adhering to the detection unit can be reliably transferred to the substrate to be printed, and the detection unit image can be printed. Therefore, by comparing the density of the detection part image and the density of the solid part image, it is easy to determine whether the printing pressure is the appropriate printing pressure or the overprinting pressure regardless of the magnitude of the ani pressure. It becomes possible to judge.

It is a schematic block diagram of the relief printing plate production apparatus for producing the relief printing plate concerning this embodiment. 1 is a schematic configuration of a flexographic printing machine that performs printing on a printing medium using a printing relief plate created by the printing relief printing plate creation apparatus of FIG. 1 and a printing pressure determination device that determines the magnitude of the printing pressure of the printing relief plate. FIG. It is a schematic block diagram of the laser engraving machine which comprises the engraving type CTP drawing machine of FIG. FIG. 2 is a schematic plan view of a printing relief plate created by the printing relief printing plate production apparatus of FIG. 1. It is sectional drawing along the VV line of FIG. It is sectional drawing along the VI-VI line of FIG. It is sectional drawing along the VII-VII line of FIG. It is a flowchart which shows operation | movement (printing pressure determination method) of the printing pressure determination apparatus which concerns on this embodiment. It is explanatory drawing of the table which shows the relationship between the printing pressure memorize | stored in the memory of FIG. 2, and optical density.

  Preferred embodiments of the present invention will be given and described in detail below with reference to the accompanying drawings.

[Description of Printing Plate Making Device and Printing Plate Making Method According to this Embodiment]
As shown in FIG. 1, the printing relief plate creating apparatus 10 according to the present embodiment basically includes a RIP (Raster Image Processor) processing unit 12, a screening processing unit 14, a plate shape determination unit 16, and a printing. And a letterpress creating part 18 for printing.

  The RIP processing unit 12 generates page description language (PDF) data such as PDF (Portable Document Format) data and PS (PostScript (registered trademark)) data representing a vector image of a printed document edited using a computer or the like. The raster image data Ir is developed.

  The screening processing unit 14 screens the raster image data Ir under conditions such as a predetermined network (AM halftone dot, FM halftone dot, halftone dot shape), angle, screen line number, and the like to obtain binary image data. Conversion to Ib (step of generating binary image data).

  The plate shape determining unit 16 processes the surface of a flexographic plate material (elastic material made of synthetic resin or rubber) into a desired shape according to a vector image, and forms a printing relief plate C according to this embodiment to be described later. In order to create, the binary image data Ib is converted into height level data Lh corresponding to the desired shape (step of generating shape data). That is, the height level data Lh is shape data indicating the height position of the projections and the like formed on the surface (plate surface) of the printing relief plate C.

  The printing relief creating unit 18 includes a data conversion unit 18a and an engraving CTP (Computer To Plate) drawing machine 18b. The data conversion unit 18a converts the height level data Lh into depth data D indicating the distance in the depth direction of the flexographic printing plate. The engraving type CTP drawing machine 18b creates a printing relief plate C on which a plurality of protrusions and the like are formed by performing laser engraving processing on the flexographic printing plate material based on the depth data D (creates a printing relief plate). Step).

[Description of Printing Apparatus and Printing Method According to this Embodiment]
As shown in FIG. 2, a flexographic printing machine 20 as a printing apparatus according to this embodiment includes a printing relief plate C as a flexographic printing plate prepared as described above, and the printing relief plate C is a double-sided tape or the like. A plate cylinder 24 attached via a cushion tape 22, an anilox roller 28 to which ink is supplied by a doctor chamber 26, and an impression cylinder 30.

  When ink is transferred from the anilox roller 28 to the projections formed on the surface (plate surface) of the printing relief plate C (step of transferring ink to the printing relief plate), the ink attached to the projections is used for printing. It is transferred (transferred) to a printing body 32 such as corrugated board which is sandwiched and conveyed between the plate cylinder 24 to which the relief plate C is attached and the impression cylinder 30. Various images including halftone dots are formed (printed) on the printing medium 32 by transferring ink from the protrusions or the like to the printing medium 32, and a desired printed matter P is created (step of printing halftone dots). .

  Note that the basic configurations of the relief printing plate making apparatus 10 and the flexographic printing machine 20 are disclosed in, for example, Japanese Patent Application Laid-Open No. 2011-224878 and Japanese Patent Application Laid-Open No. 2011-227304. Detailed description thereof will be omitted.

[Description of Printing Pressure Determination Device According to the Present Embodiment]
A printing pressure determination apparatus according to the present embodiment, which includes an imaging unit 34, a determination processing unit 36, and a memory 38 on the downstream side (downward in FIG. 2) of the printed material P (the printed material 32 after printing). 39 is arranged.

  The imaging unit 34 is a camera that captures an image printed on the printed matter P, and outputs an imaging signal indicating the captured image to the determination processing unit 36.

  The determination processing unit 36 detects the optical density of a predetermined portion in the image indicated by the imaging signal. In this case, the memory 38 stores a table indicating the relationship between the optical density of a predetermined portion and the printing pressure applied to the plate surface of the printing relief plate C during printing. The determination processing unit 36 refers to the table stored in the memory 38 and specifies (estimates) the printing pressure according to the detected optical density. Then, if the specified printing pressure is less than a predetermined printing pressure threshold, the determination processing unit 36 determines that the printed matter P has been printed with the optimum printing pressure (appropriate printing pressure), while the specified printing pressure is If it is equal to or higher than the printing pressure threshold, it is determined that the printed matter P is printed with an excessive printing pressure (overprinting pressure). The determination result in the determination processing unit 36 is notified to the outside.

  The detailed operation (printing pressure determination method) of the printing pressure determination device 39 will be described later.

[Description of the relief printing plate according to the present embodiment]
Prior to the description of the printing relief plate C, the laser engraving machine 40 constituting the engraving type CTP drawing machine 18b for producing the printing relief plate C will be described with reference to FIG.

  The laser engraving machine 40 includes an exposure head 42, a focus position changing mechanism 44, and an intermittent feeding mechanism 46 in the sub-scanning direction AS.

  The focus position changing mechanism 44 includes a motor 50 and a ball screw 52 that move the exposure head 42 back and forth with respect to the drum 48 to which the flexographic plate material (plate material) F is attached. The focus position is changed under the control of the motor 50. be able to.

  The intermittent feed mechanism 46 moves the stage 54 on which the exposure head 42 is mounted in the sub-scanning direction AS, and includes a ball screw 56 and a sub-scan motor 58 that rotates the ball screw 56. By controlling the sub-scanning motor 58, the exposure head 42 is intermittently fed in the direction of the axis 60 of the drum 48.

  The flexographic printing material F is chucked by the chuck member 62 on the drum 48. The position of the chuck member 62 is set in a region where exposure by the exposure head 42 is not performed. In this case, the surface of the flexographic printing plate F is projected by irradiating the flexographic printing plate F on the rotating drum 48 with the laser beam L from the exposure head 42 while rotating the drum 48 about the axis 60. Laser engraving is performed to form a portion or the like. Then, when the chuck member 62 passes in front of the exposure head 42 by the rotation of the drum 48, laser engraving for the next line is performed by performing intermittent feeding in the sub-scanning direction AS.

  In this way, the exposure operation position is controlled by repeating the feeding of the flexographic printing plate F in the main scanning direction MS by the rotation of the drum 48 and the intermittent feeding of the exposure head 42 in the sub-scanning direction AS. The intensity and on / off of the laser beam L are controlled by the depth data D for each exposure operation position. As a result, a protrusion or the like, which is a relief having a desired shape, is laser engraved on the main surface (plate surface) of the flexographic plate material F.

  The flexographic printing material F on which the protrusions and the like are formed in this manner is used as a printing relief plate C, and is mounted on the flexographic printing machine 20 described above.

  Next, the printing letterpress C according to this embodiment will be described with reference to FIGS.

  As shown in FIG. 4, in the printing relief plate C, the ink is transferred from the anilox roller 28 (see FIG. 2), and the transferred ink is transferred (transferred) to the printing body 32. A line forming region 70, a solid portion 72, and a plurality of detection portions 74 having substantially the same shape are formed.

  In this case, a frame-like solid portion 72 is formed along four sides of the plate surface of the substantially rectangular printing relief plate C, and the inside of the solid portion 72 is formed as the image line forming region 70. In addition, a plurality of rectangular detection units 74 are provided at predetermined intervals on two opposing sides of the frame-like solid portion 72.

  As shown in FIGS. 4 and 5, the image line forming region 70 is formed as a concave portion in which the central portion of the printing plate of the printing relief plate C is recessed downward (plate cylinder 24 side), and a plurality of protrusions are formed in the concave portion. 76a to 76c are formed.

  Each of the projecting portions 76 a to 76 c is formed in a trapezoidal cross section, and the top portions 78 a to 78 c are all set to be lower than the height of the solid portion 72. Moreover, although each top part 78a-78c is made into flat shape, it may become a round shape according to the processing precision of the laser engraving machine 40 in fact. In the present embodiment, it is desirable that at least the top portion 78c is flat.

  Of the plurality of protrusions 76a to 76c, the top part 78c of the protrusion part (highlight protrusion part) 76c is set lower than the top parts 78a and 78b of the other protrusion parts 76a and 76b. Here, Lhc is the height from the bottom surface 80 to the top 78c of the concave portion, which is the image forming area 70, and Dhc is the depth from the height of the solid portion 72 to the top 78c.

  Note that the height Lhc is a part of the height level data Lh supplied from the plate shape determination unit 16 (see FIG. 1) to the printing relief plate creating unit 18, and the depth Dhc is engraved from the data conversion unit 18a. This is a part of the depth data D supplied to the mold CTP drawing machine 18b. That is, the height level data Lh includes the height of each of the protrusions 76a to 76c including the height Lhc, the height of the solid portion 72, and the height of the detection unit 74, and the depth data D includes , The depth of each of the projecting portions 76a to 76c including the depth Dhc, the depth of the solid portion 72, and the depth of the detecting portion 74 are included. That is, the plate shape determination unit 16 (see FIG. 1) described above uses the shapes of the solid portion 72, the detection unit 74, and the projections 76a to 76c formed on the plate surface of the printing relief plate C as the height level data Lh. It is output to the letterpress creating section 18 for printing.

  On the other hand, the plurality of detecting portions 74 are formed as concave portions that are recessed downward (on the plate cylinder 24 side) in the solid portion 72, and the concave portions can be distinguished from the respective protruding portions 76a to 76c. It is formed wider than 76c. The depth Dd of the bottom surface 82 of the recess is the same as the depth Dhc. Therefore, in FIG. 5, the height position of the top 78c of the lowest protrusion 76c and the height of the bottom surface 82 of each detection unit 74 are shown. The position matches.

  In the present embodiment, as shown in FIG. 6, the height position of the bottom surface 82 of each detection unit 74 may be slightly higher than the height position of the top portion 78c of the lowest protrusion 76c. Then, as shown in FIG. 7, the height positions of the top portions 78a and 78b of the other projection portions 76a and 76b may be matched with the height position of the top portion 78c of the lowest projection portion 76c.

  That is, in the present embodiment, (1) the top portions 78a to 78c and the bottom surface 82 are lower than the solid portion 72, and (2) among the top portions 78a to 78c, the lowest top portion 78c and the bottom surface 82 are substantially equal in height. It is preferably set to (the same height or a height at which the bottom surface 82 is slightly higher).

  When the printing relief plate C configured as described above is attached to the plate cylinder 24 via the cushion tape 22, ink is supplied from the anilox roller 28 to the printing plate surface of the printing relief plate C, and the printing plate surface is subjected to an appropriate printing pressure. Then, the plate surface comes into a kiss touch state with respect to the printing body 32 when the printing body 32 comes into contact.

  As a result, the ink adhering to the solid portion 72 is firmly transferred to the printing medium 32, and an image having an optical density of about 100% corresponding to the shape of the solid portion 72 (a frame-shaped solid image without halftone dots ( A solid image)) is printed on the printing material 32.

  In addition, the ink supplied from the anilox roller 28 is accommodated in the recess of the detection unit 74. In this case, the ink stored in the detection unit 74 is transferred to the printing medium 32 with a light touch. As a result, an optical density (detection part image) corresponding to the shape of the detection part 74 having a sufficiently low optical density as compared with the solid part image is printed on the printing medium 32.

  Further, the ink supplied from the anilox roller 28 is also stored in the concave portion of the image forming area 70. In this case, the ink adhering to the top portions 78a to 78c of the protrusions 76a to 76c is transferred to the printing medium 32 with a light touch. As a result, a halftone dot image (protruding portion image) corresponding to the shape of the top portions 78a to 78c is printed on the printing medium 32 with a sufficiently low optical density as compared with the solid portion image.

  Of the above-described images, the protruding portion image which is a halftone dot image is an image corresponding to the printed document. The lowest protrusion 76c functions as a highlight protrusion for printing a highlight halftone dot on the printing medium 32, and the ani pressure applied to the plate surface of the printing relief plate C from the anilox roller 28 The pressure is set to a low pressure (minimum pressure) at which ink is supplied to the portion 76c. Further, the appropriate printing pressure is such that the ink adhering to the top portion 78c of the projecting portion 76c as the highlight projecting portion is reliably transferred to the printing material 32 and the dot for highlighting is printed. And a sufficiently low optimum pressure (pressure lower than a predetermined printing pressure threshold).

  On the other hand, if the printing pressure applied to the plate surface of the printing relief plate C is excessive printing pressure (overprinting pressure) equal to or higher than the printing pressure threshold, in addition to the ink adhering to the solid portion 72, the ink accommodated in the detecting portion 74 The image is firmly transferred to the substrate 32. As a result, an optical density that is substantially equal to the optical density of the solid part image and that corresponds to the planar shape of the detection part 74 is printed on the printing medium 32. Therefore, the optical density of the detection portion image is compared with the optical density of the solid portion image, and if the optical density of the detection portion image reaches the optical density of the solid portion image, the printing pressure applied to the printing plate of the printing relief plate C is determined. It can be easily determined that is overprinting pressure.

  The solid portion 72 has a plurality of detection portions 74 formed therein. Therefore, among the detection unit images corresponding to each detection unit 74, the number of detection unit images (the number of detection unit images determined to be overprinting pressure) that exhibits an optical density substantially equal to the optical density of the solid image, The number of detection unit images (the number of detection unit images determined to be appropriate printing pressure) that shows an optical density lower than the optical density of the partial image is counted, and (the detection unit image determined to be overprinting pressure) is determined by majority vote. If the number of detected images is determined to be an appropriate printing pressure, the printing pressure applied to the printing plate C may be determined to be an excessive printing pressure.

[Description of Printing Pressure Determination Method According to this Embodiment]
The printing relief plate C according to the present embodiment is configured as described above. Next, based on the solid part image and the detection part image printed on the printed matter P using the printing relief plate C, it is determined whether the printing pressure applied to the printing relief plate C is an appropriate printing pressure or an overprinting pressure. A method (an operation of the printing pressure determination device 39 according to the present embodiment (printing pressure determination method)) will be described with reference to FIGS. In addition, in this description, it demonstrates, also referring FIGS. 1-7 as needed.

  Here, for ease of explanation, a description will first be given of a case in which appropriate printing pressure or overprinting pressure is determined based on a comparison between a detection unit image corresponding to one detection unit 74 and a solid image. To do. Next, each of the detection unit images corresponding to the plurality of detection units 74 and the solid part image are respectively compared to determine an appropriate printing pressure or an overprinting pressure. The case of determining whether the printing pressure is the proper printing pressure or the overprinting pressure will be described.

  In step S1 of FIG. 8, the imaging unit 34 (see FIG. 2) captures a solid part image and a detection part image (including each image of the printed matter P) printed on the printed matter P, and shows each captured image. The imaging signal is output to the determination processing unit 36.

  In step S <b> 2, the determination processing unit 36 detects the optical densities of the detection unit image and the solid unit image indicated by the input imaging signal.

  In step S3, the determination processing unit 36 refers to a table indicating the relationship between the optical density Nc stored in advance in the memory 38 and the printing pressure Pc applied to the printing relief plate C shown in FIG. The printing pressure Pc is specified from Nc.

  Note that the optical density of the solid image is an optical density of about 100% regardless of the difference between the appropriate printing pressure and the overprinting pressure, and the optical density equal to or higher than the density threshold value Nth. Therefore, the determination processing unit 36 specifies the printing pressure Pc from the optical density Nc only for the detection unit image.

  In step S4, the determination processing unit 36 determines whether or not the printing pressure Pc has reached a predetermined printing pressure threshold Pth (printing pressure corresponding to the density threshold Nth). When P ≧ Pth (step S4: YES), the determination processing unit 36 determines that the printing pressure Pc is an overprinting pressure, and notifies the outside of a determination result indicating the overprinting pressure (step S5). ). On the other hand, if Pc <Pth (step S4: NO), the determination processing unit 36 determines that the printing pressure Pc is an appropriate printing pressure, and notifies the outside of a determination result indicating that the printing pressure is an appropriate printing pressure ( Step S6).

  That is, if the printing pressure Pc is an appropriate printing pressure less than the printing pressure threshold value Pth, the ink stored in the detection unit 74 is transferred to the printing medium 32 with a light touch, and the detection unit formed by the transferred ink. The optical density of the image is sufficiently lower than the optical density of the solid image (optical density equal to or higher than the density threshold Nth). On the other hand, if the printing pressure Pc is an overprinting pressure equal to or higher than the printing pressure threshold value Pth, the ink stored in the detection unit 74 is firmly transferred to the printing medium 32 and the detection unit image formed by the transferred ink. The optical density becomes an optical density (density threshold Nth) substantially equal to the optical density of the solid image.

  Therefore, by comparing the printing pressure Pc corresponding to the optical density Nc of the detection portion image with the printing pressure threshold value Pth corresponding to the density threshold value Nth which is the lowest optical density of the solid portion image, the printing pressure Pc is obtained. It is possible to easily determine whether the printing pressure is appropriate or excessive printing pressure, and to notify the determination result to the outside.

  As described above, since the optical density according to the printing pressure threshold value Pth is the density threshold value Nth, the determination processing unit 36 determines the printing pressure based on the comparison between the optical density Nc and the density threshold value Nth in step S4. It may be determined whether Pc is an appropriate printing pressure or an excessive printing pressure.

  The above description is the description of the appropriate printing pressure or overprinting pressure determination process based on the comparison between the detection unit image corresponding to one detection unit 74 and the solid image corresponding to the solid unit 72.

  Next, a description will be given of a case where appropriate detection pressure or overprinting pressure is determined by comparing each detection unit image corresponding to a plurality of detection units 74 and a solid image.

  In step S <b> 1, the imaging unit 34 captures a solid part image printed on the printed material P and a plurality of detection unit images (including each image of the printed material P), and determines an imaging signal indicating each captured image. To 36.

  In step S <b> 2, the determination processing unit 36 detects the optical densities of the detection unit images and the solid image indicated by the input imaging signal.

  In step S3, the determination processing unit 36 refers to the table shown in FIG. 9 stored in advance in the memory 38, and specifies the printing pressure Pc from the optical densities Nc of the plurality of detection unit images.

  In step S4, the determination processing unit 36 compares one printing pressure Pc with the printing pressure threshold value Pth among the plurality of specified printing pressures Pc. In this case, even if Pc ≧ Pth (step S4: YES) or Pc <Pth (step S4: NO), the determination processing unit 36 executes the process of the next step S7.

  In the next step S7, the determination processing unit 36 returns to step S4 if the determination processing in step S4 for a plurality of printing pressures Pc corresponding to all the detection unit images has not been completed (step S7: NO). The determination process for the printing pressure Pc that has not been processed is executed.

  On the other hand, when the determination processing for all the printing pressures Pc is completed (step S7: YES), the determination processing unit 36 determines the number of printing pressures Pc determined to be overprinting pressure for all the printing pressures Pc in step S8. Is determined to be a majority.

  If the number of printing pressures Pc determined as overprinting pressure is a majority, the determination processing unit 36 determines that the printing pressure of the printing relief plate C is overprinting pressure (step S8: YES), and the process proceeds to step S5. Execute the process. On the other hand, if the number of printing pressures Pc determined to be excessive printing pressure has not reached the majority (when the number of printing pressures Pc determined to be appropriate printing pressure is a majority), the determination processing unit 36 performs printing. It determines with the printing pressure of the letterpress C being an appropriate printing pressure (step S8: NO), and performs the process of step S6.

  Note that the determination processing unit 36 may detect only the optical density of one detection unit image among the plurality of detection unit images indicated by the input imaging signal in step S2. In this case, if the determination process for all the detection unit images is not completed in step S7, the process returns to step S2, and the processes of steps S2 to S4 are performed again.

  Further, in step S3, the determination processing unit 36 may specify the printing pressure Pc for the optical density Nc of one detection unit image among the optical densities of the plurality of detection unit images. In this case, if the determination process for all the detection unit images is not completed in step S7, the process returns to step S3, and the processes of steps S3 and S4 are performed again.

[Effect of this embodiment]
As described above, according to this embodiment, in the printing relief plate C, the lowest protrusion 76c and the detection unit 74 are set to have substantially the same height. Therefore, for example, even if the ani pressure is set to the lowest pressure that matches the printing conditions of the printing medium 32, ink can be supplied to the protrusions 76c and the detection unit 74 having substantially the same height. The ink adhering to 74 can be reliably transferred to the printing medium 32 and the detection portion image can be printed. Therefore, by comparing the optical density Nc of the detection portion image with the optical density (density threshold value Nth) of the solid portion image, regardless of the magnitude of the ani pressure, the printing pressure Pc is the appropriate printing pressure or the overprinting pressure. It is possible to easily determine whether it is.

  Further, the solid portion 72 is a portion that is substantially flat and has a certain area or more on the printing surface of the printing relief plate C, and is formed at a position higher than other portions that constitute the printing relief plate C. Therefore, when the printing pressure Pc is an appropriate printing pressure, the printing surface of the relief printing plate C is in a kiss touch state with respect to the printing body 32, and the ink is firmly transferred from the solid portion 72 to the printing body 32. The ink is transferred from the detection unit 74 to the printing material 32 with a light touch. In this case, the optical density of the solid image is approximately 100%, and the optical density Nc of the detection image is sufficiently lower than that of the solid image.

  On the other hand, if the printing pressure Pc is an overprinting pressure (pressure equal to or higher than the printing pressure threshold value Pth), the ink is firmly transferred from the detection unit 74 to the printing medium 32, so the optical density Nc of the detection unit image is a solid portion. It becomes substantially equal to the optical density of the image. Therefore, by comparing the optical density Nc of the detection portion image with the optical density of the solid portion image, it can be easily determined whether or not the printing pressure Pc is an excessive printing pressure.

  Further, the detection unit 74 is a recess formed in the solid portion 72, and the height position of the bottom surface 82 of the recess and the height position of the top portion 78c of the projection 76c are substantially equal. It is possible to store the ink thus stored in the concave portion and reliably transfer the stored ink to the printing medium 32.

  Furthermore, if at least the top part 78c of the protrusion 76c is formed as a flat part, the image quality of the halftone dots formed by the ink transferred from the protrusion 76c to the printing medium 32 can be improved.

  In addition, even if the height position of the detection part 74 is the same height position as the projection part 76c, or a position slightly higher than the projection part 76c, each effect mentioned above is acquired easily. Of course, the above-described effects can be obtained even when the protrusions 76a to 76c are set at the same height as the protrusion 76c.

  Furthermore, the printing relief plate C may have a certain degree of height variation (height distribution) as a whole. In view of this, a plurality of detection units 74 are provided, and the printing pressure Pc is determined to be appropriate by a majority decision based on a comparison result between the optical density Nc of each detection unit image and the optical density of the solid image corresponding to each detection unit 74. If the pressure or overprinting pressure is determined, the influence on the determination result of the printing pressure due to the height variation of each detection unit 74 is suppressed, and the appropriate printing pressure or overprinting pressure is determined accurately. It can be carried out.

  The printing letterpress creating apparatus 10, the printing letterpress creating method, the flexographic printing machine 20, the printing method, the printing pressure judgment device 39, and the printing pressure judgment method are all apparatuses or methods related to the printing letterpress C described above. Therefore, it is possible to achieve the above-described effects by the printing letterpress C.

  In the above description, the case has been described in which the printing pressure determination device 39 and the printing pressure determination method automatically determine whether the printing pressure Pc is the appropriate printing pressure or the excessive printing pressure. In the present embodiment, the printing pressure Pc is appropriate based on the comparison between the optical density Nc of the detection unit image (the printing pressure Pc corresponding to the density image) and the density of the solid image (the printing pressure threshold value Pth corresponding to the density threshold value Nth). Since it suffices to determine whether the printing pressure or overprinting pressure, the operator visually compares the optical density Nc of the detection portion image with the density of the solid portion image, and the printing pressure Pc is the appropriate printing pressure or overprinting. It is also possible to determine which is the pressure.

  Of course, the present invention is not limited to the above-described embodiment, and various modifications are possible.

DESCRIPTION OF SYMBOLS 10 ... Printing letterpress preparation apparatus 12 ... RIP process part 14 ... Screening process part 16 ... Plate shape determination part 18 ... Printing letterpress preparation part 18a ... Data conversion part 18b ... Engraving type CTP drawing machine 20 ... Flexographic printing machine 24 ... Plate Cylinder 26 ... Doctor chamber 28 ... Anilox roller 30 ... Impression cylinder 32 ... Printed body 34 ... Imaging unit 36 ... Determination processing unit 38 ... Memory 39 ... Printing pressure judgment device 40 ... Laser engraving machine 70 ... Image formation area 72 ... Solid Part 74: Detection part 76a-76c ... Projection part 78a-78c ... Top part 80, 82 ... Bottom

Claims (12)

In the printing relief plate provided on the surface of the plate material, and formed with protrusions for transferring halftone dots by transferring ink to the printing medium,
On the surface of the plate material, there are a solid part, an image line forming region in which a plurality of protrusions are formed, and a mark applied to the printing relief plate when ink is transferred from the printing relief plate to the substrate. A detection unit for determining the magnitude of pressure is provided,
The detection part is a recess formed in the solid part,
The height position of the bottom surface of the recess and the height position of the top of the projection for highlight that is lower than the solid portion and the lowest among the projections are set to substantially equal heights,
Is printed to said printing material and density of the detector image printed to said printing material by transfer of ink to the printing substrate from said concave portion, by transfer of ink to the printing substrate from the solid portion It is possible to determine whether or not the printing pressure is an appropriate printing pressure by comparison with the density of the solid image. In the letterpress for printing according to claim 1,
If the density of the detection part image is lower than the density of the solid part image, it is determined that the printing pressure is appropriate. On the other hand, the density of the detection part image and the density of the solid part image are substantially equal. If it is equal, it is determined that the printing pressure is an overprinting pressure. In the letterpress for printing according to claim 1 or 2 ,
At least a top portion of the highlight protrusion is formed as a flat portion. In the relief printing plate of any one of Claims 1-3 ,
The height of the bottom surface of the recess is the same height as the top of the highlight protrusion, or is slightly higher than the top of the highlight protrusion. Letterpress for printing. In the relief printing plate of any one of Claims 1-4 ,
Each of the protrusions is set at the same height position as the highlight protrusion. In the relief printing plate of any one of Claims 1-5 ,
On the surface of the plate material, the concave portion is formed in plural,
Wherein the ink is transferred is transferred to each of the medium to be printed from the concave portions, a plurality of the detector image to said printing substrate is printed,
The density of each detection unit image is compared with the density of the solid image, and by the majority of the number of detection unit images according to the appropriate printing pressure and the number of detection unit images according to overprinting pressure, It is determined whether the printing pressure is the appropriate printing pressure or the overprinting pressure. In a relief printing plate making apparatus for creating a printing relief plate provided with projections on the surface of a plate material for transferring halftone dots by transferring ink to a printing medium,
On the surface of the plate material, there are a solid part, an image line forming region in which a plurality of protrusions are formed, and a mark applied to the printing relief plate when ink is transferred from the printing relief plate to the substrate. A detection unit for determining the magnitude of pressure is provided,
The printing letterpress creating apparatus is
A binary image data generation unit that generates binary image data based on multi-value image data representing a print image;
Based on the binary image data, a plate shape determining unit that generates shape data indicating each shape of the solid part, the image forming region including the protrusions, and the detection unit;
A relief printing plate creating section for creating the printing relief plate based on the shape data;
Have
The detection part is a recess formed in the solid part,
The height position of the bottom surface of the recess and the height position of the top of the projection for highlight that is lower than the solid portion and the lowest among the projections are set to substantially equal heights,
Is printed to said printing material and density of the detector image printed to said printing material by transfer of ink to the printing substrate from said concave portion, by transfer of ink to the printing substrate from the solid portion It is possible to determine whether or not the printing pressure is an appropriate printing pressure by comparison with the density of the solid image. In a printing relief printing method for creating a printing relief plate in which protrusions for transferring halftone dots by transferring ink to a printing material are provided on the surface of the plate material,
On the surface of the plate material, there are a solid part, an image line forming region in which a plurality of protrusions are formed, and a mark applied to the printing relief plate when ink is transferred from the printing relief plate to the substrate. A detection unit for determining the magnitude of pressure is provided,
The printing relief plate making method is:
Generating binary image data based on multivalued image data representing a print image;
Based on the binary image data, generating shape data indicating each shape of the solid portion, the image forming region including the projections, and the detection unit;
Creating the relief printing plate based on the shape data;
Have
The detection part is a recess formed in the solid part,
The height position of the bottom surface of the recess and the height position of the top of the projection for highlight that is lower than the solid portion and the lowest among the projections are set to substantially equal heights,
Is printed to said printing material and density of the detector image printed to said printing material by transfer of ink to the printing substrate from said concave portion, by transfer of ink to the printing substrate from the solid portion It is possible to determine whether or not the printing pressure is an appropriate printing pressure by comparison with the density of the solid image. In a printing apparatus that prints halftone dots on a printing material by transferring ink from the protrusions provided on the surface of the printing relief plate material to the printing material,
Anilox Roller,
A printing cylinder to which the printing relief plate is attached and ink is transferred from the anilox roller to the printing relief plate;
By sandwiching the printing medium in cooperation with the plate cylinder to which the printing relief plate is attached, ink is transferred from the protrusions to the printing medium so that the halftone dots are formed on the printing medium. An impression cylinder to be printed;
Have
On the surface of the plate material, there are a solid part, an image line forming region in which a plurality of protrusions are formed, and a mark applied to the printing relief plate when ink is transferred from the printing relief plate to the substrate. A detection unit for determining the magnitude of pressure is provided,
The detection part is a recess formed in the solid part,
The height position of the bottom surface of the recess and the height position of the top of the projection for highlight that is lower than the solid portion and the lowest among the projections are set to substantially equal heights,
Is printed to said printing material and density of the detector image printed to said printing material by transfer of ink to the printing substrate from said concave portion, by transfer of ink to the printing substrate from the solid portion It is possible to determine whether or not the printing pressure is an appropriate printing pressure by comparison with the density of the solid image. In the printing method of printing halftone dots on the printing medium by transferring ink from the protrusions provided on the surface of the printing relief plate material to the printing medium,
Transferring the ink from the anilox roller to the printing relief plate attached to the plate cylinder;
In a state where the printing medium is sandwiched between the plate cylinder and the impression cylinder to which the printing relief plate is attached, ink is transferred from the protrusions to the printing medium, and the halftone dots are formed on the printing medium. Printing step;
Have
On the surface of the plate material, a solid portion, an image line forming region in which a plurality of the protrusions are formed, and a mark applied to the printing relief plate when transferring ink from the printing relief plate to the printing medium. A detection unit for determining the magnitude of pressure is provided,
The detection part is a recess formed in the solid part,
The height position of the bottom surface of the recess and the height position of the top of the projection for highlight that is lower than the solid portion and the lowest among the projections are set to substantially equal heights,
Is printed to said printing material and density of the detector image printed to said printing material by transfer of ink to the printing substrate from said concave portion, by transfer of ink to the printing substrate from the solid portion It is possible to determine whether or not the printing pressure is an appropriate printing pressure by comparing with the density of the solid image. When printing halftone dots on the printing material by transferring ink from the protrusions provided on the surface of the printing relief plate material to the printing material, the printing pressure applied to the printing relief plate is determined. In the printing pressure determination device for determining,
On the surface of the plate material, there are a solid part, an image line forming region in which a plurality of protrusions are formed, and a mark applied to the printing relief plate when ink is transferred from the printing relief plate to the substrate. A detection unit for determining the magnitude of pressure is provided,
The detection part is a recess formed in the solid part,
The height position of the bottom surface of the recess and the height position of the top of the projection for highlight that is lower than the solid portion and the lowest among the projections are set to substantially equal heights,
The printing pressure determination device includes:
It is printed to said printing medium detecting unit image printed to said printing material, and, by transfer of ink to the printing substrate from the solid portion by transition from the concave portion of the ink to the printing substrate An imaging unit that captures a solid image;
A determination unit that determines whether the printing pressure is an appropriate printing pressure based on a comparison between the density of the detection unit image captured by the imaging unit and the density of the solid image;
A printing pressure determination device comprising: When printing halftone dots on the printing material by transferring ink from the protrusions provided on the surface of the printing relief plate material to the printing material, the printing pressure applied to the printing relief plate is determined. In the printing pressure determination method for determining,
On the surface of the plate material, there are a solid part, an image line forming region in which a plurality of protrusions are formed, and a mark applied to the printing relief plate when ink is transferred from the printing relief plate to the substrate. A detection unit for determining the magnitude of pressure is provided,
The detection part is a recess formed in the solid part,
The height position of the bottom surface of the recess and the height position of the top of the projection for highlight that is lower than the solid portion and the lowest among the projections are set to substantially equal heights,
The printing pressure determination method is:
It is printed to said printing medium detecting unit image printed to said printing material, and, by transfer of ink to the printing substrate from the solid portion by transition from the concave portion of the ink to the printing substrate Capturing a solid image; and
Determining whether or not the printing pressure is an appropriate printing pressure based on a comparison between the density of the imaged detection part image and the density of the solid part image;
A printing pressure determination method characterized by comprising:

Images