Flexible printing plate support

Abstract

The flexible printing plate support of the present invention includes a flexible printing plate (20) composed of a printing plate sheet (21) and a base material sheet (22), and vises (3A, 3B) that support the ends of the flexible printing plate (20) in the printing direction. At the ends of the flexible printing plate (20) in the printing direction, the ends of the base material sheet (22) protrude outward from the ends of the printing plate sheet (21). At the fastening and fixing part of the vises (3A, 3B) that combines the front-side member (6) and the back-side member (7), the protruding part (30) of the base material sheet (22) is fixed in a clamped state. With this flexible printing plate support, although the structure is simple, the reproducibility of fine printing patterns is excellent.

Description

Technical Field

[0001] The present invention relates to a flexible printing plate support formed by mounting a vice (Japanese: バイス) for mounting a printing plate cylinder on a flexible printing plate. Background Art

[0002] Flexographic printing is a printing method that uses a resin or rubber soft (flexible) flexographic printing plate (hereinafter also simply referred to as "printing plate") having convex portions for printing (images, characters, etc.) formed on the front surface, and transfers the ink held on the top surface of the above-mentioned convex portions for printing to the printing object at a low printing pressure. The above-mentioned convex portions for printing are relatively soft and can follow the front surface of various-shaped printing objects, so this flexographic printing can be used when printing on printing objects of various materials and thicknesses.

[0003] In the printing using the above-mentioned flexographic printing plate, a rotary flexographic printing press as Figure 7 schematically shown is usually used. When printing using this flexographic printing press, first, vice 3A and 3B for mounting a printing plate cylinder are mounted at both ends of a soft sheet-like printing plate 10 to form a printing plate support, and then, with the printing plate 10 wound around the printing plate cylinder 11, the above-mentioned vice 3A and 3B are fixed to the printing plate cylinder 11. Then, by rotating the printing plate cylinder 11 while supplying ink from the anilox roll 12 to the printing plate 10, the ink held by the convex portions for printing of the printing plate 10 can be transferred to the printing object R to perform printing. Then, by repeating the above series of operations, the same graphic (image, character) can be continuously printed on the printing object R.

[0004] In addition, in Figure 7 the reference numeral 13 is a doctor blade (doctor knife) for uniformly supplying ink from the anilox roll 12 to the front surface of the printing plate 10, and the reference numeral 14 is an ink tank. In addition, the reference numeral 16 is a moving table that positions the printing object R at an appropriate position relative to the printing plate 10 and conveys the printing object R forward while pressing it against the printing plate 10.

[0005] Regarding the printing plate 10 in the above-mentioned printing plate support, as shown in (a) of Figure 8 which is a top view thereof and (b) of Figure 8 which is a front view thereof, the printing plate 10 is substantially rectangular in top view, the front side of the printing plate 10 that becomes the printing surface is composed of a printing plate sheet 1, the printing plate sheet 1 includes a flexible sheet-like body, and the back side of the printing plate 10 is composed of a base material sheet 2 for strengthening the above-mentioned printing plate sheet 1. In addition, the base material sheet 2 may be a single sheet or a multi-layer sheet formed by overlapping multiple sheets. In this example, it has a structure formed by overlapping two sheets.

[0006] The front side of the printing plate 10, i.e., the front side of the printing plate sheet 1, is provided with a printing convex portion 1a, and the surrounding of the printing convex portion 1a is a non-printing portion 1b that does not participate in printing. In addition, at both ends of the printing plate sheet 1 in the printing direction (indicated by thick arrows in the figure), a thin curved portion 1c is provided for facing the printing plate cylinder 11 (refer to FIG. Figure 7 ) is mounted on the plate cylinder, and each clamp portion 1d is provided with a positioning hole 5, through which a plurality of positioning pins 4 arranged at predetermined intervals on the side of the vise 3A, 3B (indicated by a two-dot chain line) for assembling the plate cylinder are inserted (see Figure 9 ).

[0007] Furthermore, by placing the printing plate 10 at both ends or one end (in the printing direction) of the printing plate 10, Figure 9 Only one of the vises 3A and 3B installed at both ends is shown in the figure. The vise 3A (clamp head side) and the vise 3B (clamp tail side) for assembling the plate cylinder are respectively installed to obtain a printing plate support. When the vises 3A and 3B are installed at both ends, their installation structure becomes bilaterally symmetrical in most cases. Figure 8 The installation structure will be described by taking the bench vise 3B installed on the right side in the orientation of (a) as an example.

[0008] like Figure 9 As shown, the bench vise 3B includes a front side member 6 disposed on the front side of the end of the printing plate 10 and a back side member 7 disposed on the back side of the end of the printing plate 10. The front side member 6 and the back side member 7 are fastened and fixed by a screw member 8 in a state where the end (clamp portion 1d) of the printing plate 10 is sandwiched between the front side member 6 and the back side member 7. Reference numeral 9 is a screw hole provided in the back side member 7. In this state, the front side of the clamp portion 1d of the printing plate 10, that is, the front side of the printing plate sheet 1, is pressed downward by the downwardly facing flat surface portion 6a of the front side member 6 of the bench vise 3B, and the entire end of the printing plate 10 is clamped between the flat surface portion 6a of the front side member 6 and the flat surface portion 7a of the back side member 7 of the bench vise 3B. In addition, the end face 10a of the printing plate 10 in the printing direction is opposite to the step portion 6b of the above-mentioned front side member 6, and the end face 10a of the printing plate 10 is surrounded by the step portion 6b and the flat portion 6a of the above-mentioned front side member 6, and the end face 10a of the printing plate 10 is protected from the outside.

[0009] The structure of the printing plate support body formed by installing the above-mentioned bench vises 3A and 3B has the following advantages: If the bench vises 3A and 3B are touched, the printing plate 10 can be processed without damaging the shape of the printing convex part 1a of the printing plate 10 and the physical properties of the entire printing plate 10, and the assembly and replacement of the printing plate 10 on the plate cylinder 11 can be easily performed. In addition, the base material sheet 2 provided on the back side of the printing plate 10 functions as a "tension member" that mainly supports the tension applied to the printing plate 10, and plays a role in protecting the soft printing plate sheet 1 from elongation and deformation.

[0010] In addition, in the past, flexible printing was characterized by environmentally friendly printing that uses water-based ink to transfer onto printed materials such as corrugated paper. However, in recent years, with the enlargement (increase in area) of flat panel displays, solar cell panels, etc., there has emerged a characteristic of being able to print a uniform thin film with good reproducibility and high speed without damaging the substrate, wiring, etc. The demand for printing (transfer forming) of electrode layers, sealants, masking agents, etc. to be provided on substrates such as liquid crystals, organic ELs, and organic TFTs has increased.

[0011] Therefore, for flexible printing, it is required to print finer printing patterns with high precision. However, since the printing surface of the printing plate is composed of a soft printing plate sheet, no matter how much the strength is enhanced by the base material sheet on the back side, when it is supplied for repeated printing in a state where tension is applied in the printing direction, there is a risk that elongation and strain will occur on the printing surface, causing the printing pattern to shift and deform. Therefore, research is being conducted to make the installation structure of the printing plate and the bench vise more firm to suppress the movement of the printing surface. For example, a scheme has been proposed to make the fitting part of the two a snap button structure so that the printing plate is not easily offset from the bench vise (refer to Patent Document 1).

[0012] Prior art documents

[0013] Patent documents

[0014] Patent Document 1: Japanese Patent No. 6355879 Gazette Summary of the Invention

[0015] Problems to be solved by the invention

[0016] However, as in the above-mentioned Patent Document 1, in the case where the fitting part of the printing plate and the bench vise is a snap button structure, since the positioning and fastening of the two are performed only through this fitting part, it is necessary to install a plurality of snap button members at the end of the printing plate with a high positioning accuracy, and there is a problem of consuming a large amount of labor in the preparation of the printing plate.

[0017] In addition, since a recess is formed on the printing plate to engage with the eyelet member, the thickness of the end of the printing plate becomes thinner by the recess and the strength becomes lower. There is also a risk that the printing plate stretches and generates strain, causing the printed pattern to shift.

[0018] Therefore, it is strongly desired to realize a mounting structure between the bench vise and the printing plate in a manner that does not become complicated, and with this mounting structure, the printing plate is less likely to stretch or deviate, and a fine printing pattern can be repeatedly printed with good reproducibility.

[0019] The present invention has been made in view of such circumstances, and provides a printing plate support having a simple structure but excellent stability of a printing plate, thereby achieving excellent reproducibility of a fine printed pattern.

[0020] Solutions for solving the problems

[0021] In order to achieve the above-mentioned purpose, the present invention adopts the following technical solutions [1] to [6].

[0022] [1] A flexible printing plate support, comprising a flexible printing plate; and a bench vise that clamps and supports the end of the flexible printing plate in the printing direction from the front side and the back side, wherein the flexible printing plate is composed of a printing plate sheet and a substrate sheet, the printing plate sheet having a convex portion for printing formed on the front side, the substrate sheet being integrally provided on the back side of the printing plate sheet and reinforcing the printing plate sheet, the bench vise comprising: a front side member that is arranged on the front side of the end of the flexible printing plate; a back side member that is arranged on the back side of the end of the flexible printing plate; and a fixing member that fastens and fixes the front side member and the back side member while the flexible printing plate is clamped between the front side member and the back side member, wherein at the end of the flexible printing plate in the printing direction, the end of the substrate sheet protrudes outwardly than the end of the printing plate sheet, and the protruding portion of the substrate sheet is fixed in a clamped state between the front side member and the back side member of the bench vise.

[0023] [2] A flexible printing plate support according to [1], wherein the front side member of the bench vise comprises: a first planar portion for pressing the front end surface of the printing plate sheet; a second planar portion for pressing the front end surface of a protruding portion of a substrate sheet protruding from the end surface of the printing plate sheet; and a step portion opposite to the end surface of the printing plate sheet.

[0024] [3] The flexible printing plate support according to [1] or [2], wherein the edge of the protruding portion of the substrate sheet protrudes from the edge of the fastening portion of the vise by 0 mm to 10 mm in the printing direction when viewed from above.

[0025] [4] The flexible printing plate support according to any one of [1] to [3] above, wherein the fixing member of the vise is composed of a threaded hole provided in either the front-side member or the back-side member, a through hole provided in the other of the front-side member and the back-side member, and a threaded member screwed into the threaded hole. A through hole for the threaded member to pass through is formed in the protruding portion of the base material sheet. The diameter D of the threaded portion of the threaded member is 2 mm to 10 mm, and the diameter H of the through hole of the base material sheet is set to a size that is 0.3 mm to 8 mm larger than the diameter D of the threaded portion.

[0026] [5] The flexible printing plate support according to any one of [1] to [4] above, wherein the fixing member of the vise is composed of a threaded hole provided in either the front-side member or the back-side member, a through hole provided in the other of the front-side member and the back-side member, and a threaded member screwed into the threaded hole. A through hole for the threaded member to pass through is formed in the protruding portion of the base material sheet. When the diameter of the through hole provided in any other one of the front-side member and the back-side member is set as J, the relationship between the size of this diameter J and the diameter H of the through hole of the base material sheet is set to the relationship shown in the following formula (1).

[0027] (J - H) ≤ 3 mm...(1).

[0028] [6] The flexible printing plate support according to any one of [1] to [5] above, wherein the thickness of the base material sheet is 0.1 mm to 1.2 mm.

[0029] In the process of repeatedly conducting research to solve the above problems, the present inventors obtained the following understanding: When, in order to prevent the offset of the printing plate, the end portion (clip portion) of the printing plate clamped by the vise is tightly locked by the vise, the relatively soft printing plate sheet portion (usually, the JIS Shore A rubber hardness is about 35 degrees to 70 degrees) will gradually deform, for example, elongation, twisting, etc. will occur, and instead, it is likely to cause the printing pattern to be offset.

[0030] In addition, it was found that when using a printing plate support having the following structure (refer to Figure 9)When a relatively high tension is applied to the printing plate support for repeated printing, deformation and cracking as if forcibly pulled are likely to occur at the opening edge of the positioning hole of the base material sheet provided on the back side of the printing plate for reinforcement. The structure of the printing plate support is such that it is positioned by engaging the positioning hole on the printing plate side with the positioning pin on the vise side and then locked into the vise for fixation. It can be imagined that when such deformation and cracking occur in the base material sheet, the soft printing plate sheet will deform in a following manner, thereby reducing the reproducibility of the printed pattern.

[0031] Therefore, instead of studying a structure for strongly locking the soft printing plate sheet on the front side of the printing plate, a structure for reliably fixing the base material sheet on the back side to keep the whole stationary was further studied.

[0032] As a result, the present invention was completed by finding the following situation. In the printing plate, the structure is such that the end of the base material sheet on the back side protrudes outward more than the end of the printing plate sheet on the front side. The protruding part is clamped and firmly fixed by the front side member and the back side member of the vise. At this time, the base material sheet is reliably fixed and does not move. Therefore, even if the end face of the end of the printing plate sheet on the front side is only surrounded within the vise and is in a free state, as a whole printing plate, elongation and deviation basically do not occur, and fine printed patterns can be reproduced well.

[0033] Effects of the invention

[0034] That is, for the printing plate support of the present invention, among the ends of the printing plate sheet and the base material sheet that were previously set to be flush in the printing plate, the end of the base material sheet is set to protrude outward more than the end of the printing plate sheet, and the protruding part is locked by the fastening and fixing part of the vise.

[0035] With this structure, the end of the base material sheet, which lacks elasticity among the ends of the printing plate that were previously relatively free, is locked into the fastening and fixing part and fixed. Therefore, undue force is not applied to the periphery of the positioning hole of the base material sheet and deformation does not occur. In addition, the relatively soft printing plate sheet part at the end of the printing plate is not forcibly locked too tightly, and this part does not deform either.

[0036] Thus, elongation and deviation are not likely to occur in the whole printing plate, and fine printed patterns can be repeatedly printed with good reproducibility. And with this structure, no extra parts are added to either the printing plate or the vise. As the vise, an existing vise can be directly installed. Therefore, it has the advantages that the installation operation of the vise to the printing plate is simple and the versatility is relatively high. Description of the Drawings

[0037] Figure 1It is a partial cross-sectional view of a printing plate support of an embodiment of the present invention.

[0038] Figure 2 It is a partial perspective view of a printing plate for the above printing plate support.

[0039] Figure 3 It is a partial cross-sectional view of a printing plate support of other embodiments of the present invention.

[0040] Figure 4 It is a schematic explanatory view of an evaluation method for elongation and offset in an embodiment of the present invention.

[0041] Figure 5 It is a graph showing the evaluation results of elongation and offset in an embodiment of the present invention.

[0042] Figure 6 It is a graph showing the evaluation results of elongation and offset in a comparative example of the present invention.

[0043] Figure 7 It is a schematic structural diagram showing an example of a conventional flexographic printing press.

[0044] Figure 8 It shows an example of a conventional printing plate for the above flexographic printing press. Figure 8 (a) of which is a top view. Figure 8 (b) of which is a front view.

[0045] Figure 9 It is a partial cross-sectional view showing an example of a conventional flexographic printing plate support.

[0046] Explanation of reference numerals

[0047] 3A, 3B, vise; 6, front side member; 7, back side member; 20, printing plate; 21, printing plate sheet; 22, base material sheet; 30, protrusion. Detailed Description of the Embodiment

[0048] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

[0049] Figure 1 It is a partial cross-sectional view of a printing plate support of an embodiment of the present invention, which is composed of a printing plate 20 and vises 3A, 3B. This printing plate support can be assembled, for example, to Figure 7 a flexographic printing press as shown for printing. For the vises 3A, 3B mounted on the above printing plate 20, it is possible to use Figure 8 (a) of Figure 8 (b) of Figure 9A conventional vise as shown. Therefore, for vises 3A and 3B, the same reference numerals are assigned to the same parts as those in these figures, and their descriptions are omitted.

[0050] On the other hand, as shown in Figure 2 which is a partial perspective view of the above-mentioned printing plate 20, the printing plate 20 has a substantially rectangular shape when viewed from above. The front side of the printing plate 20 that serves as the printing surface is composed of a printing plate sheet 21, and the printing plate sheet 21 includes a flexible sheet-like body. The back side of the printing plate 20 is composed of a base material sheet 22 for strengthening the printing plate sheet 21 [For the overall shape, refer to Figure 8 (a) of Figure 8 (b).

[0051] Moreover, at the end of the printing plate 20 in the printing direction (indicated by the thick arrow in Figure 2 , the same applies hereinafter), that is, the end on the side where the vises 3A and 3B are installed, the end of the base material sheet 22 extends and protrudes outward from the end of the printing plate sheet 21. A through hole 31 is formed in the protruding portion 30, and a threaded member 8 for fastening and fixing the front side member 6 and the back side member 7 of the vises 3A and 3B passes through the through hole 31. And as shown in Figure 1 , the protruding portion 30 of the printing plate 20 is fastened and fixed in such a way that the front side member 6 and the back side member 7 clamp the protruding portion 30 of the printing plate 20. This is the greatest feature of the present invention.

[0052] In addition, on the front side of the printing plate 20, that is, the front side of the printing plate sheet 21, printing protrusions 21a are provided in the same manner as in a conventional printing plate, and the non-printing portion 21b that does not participate in printing is provided around the printing protrusions 21a. Further, at the end of the printing plate sheet 21 in the printing direction, a clip portion 21d for mounting on the printing plate cylinder 11 (refer to Figure 7 ) is provided with a thin bending portion 21c interposed therebetween. A positioning hole 25 is provided in the clip portion 21d, and a plurality of positioning pins 4 provided at a predetermined interval on the vise 3A and 3B side pass through the positioning hole 25. And the front side of the clip portion 21d of the printing plate sheet 21 is pressed downward by the flat portion 6a of the front side member 6. In addition, the end face 21f of the clip portion 21d of the printing plate sheet 21 in the printing direction faces the step portion 6b of the front side member 6.

[0053] As the material constituting the printing plate sheet 21 in the above-mentioned printing plate 20, materials such as resin and rubber that still have a certain elasticity after plate formation can be used. In addition, for the printing plate support of the present invention, as described above, it is envisaged that it is used to transfer and form organic solvent-based inks such as electrode layers, sealants, and masking agents onto a printed body such as a substrate in the manufacturing processes of liquid crystals, organic ELs, organic TFTs, etc. Therefore, preferably, according to the types of inks, plate cleaning liquids, etc. used in the above processes, a material that is not affected by them is selected accordingly.

[0054] In addition, in the above-mentioned printing plate sheet 21, high precision is required for the shapes of the printing protrusions 21a, positioning alignment marks, etc. Therefore, when manufacturing the printing plate sheet 21, it is preferable to use a photolithography method that can form the printing protrusions 21a, positioning alignment marks, etc. into accurate shapes and at accurate positions. In this case, as the material constituting the above-mentioned printing plate sheet 21, a photosensitive resin composition can be used, and among them, a photosensitive resin composition including a mixture of a prepolymer, acrylate oligomer, acrylate monomer having a main skeleton of acrylate such as polyurethane-based, polyester-based, polybutadiene-based, etc., and a photopolymerization inhibitor, a photopolymerization initiator, etc. can be used.

[0055] Moreover, for the hardness of the above-mentioned printing plate sheet 21, it is desired to set its JIS Shore A rubber hardness within the range of 35 degrees to 70 degrees. When the above-mentioned Shore A hardness is less than 35 degrees, there is a risk that the printing protrusions 21a formed on the printing plate sheet 21 become too soft with respect to the printed body (substrate, etc.) and deform during printing, which is not ideal in terms of maintaining high-precision printing. On the contrary, when the Shore A hardness of the above-mentioned printing plate sheet 21 is greater than 70 degrees, there is a risk of damaging the surface of the printed body, electrodes, wirings, etc. formed on the surface, which is thus not ideal.

[0056] Moreover, the outer dimensions of the above-mentioned printing plate sheet 21 depend on the printed body, the printing plate cylinder 11 (refer to Figure 7), but usually, the length dimension of the printing plate sheet 21 in the printing direction is about 1000mm to 3000mm, and the width dimension of the printing plate sheet 21 perpendicular to the printing direction is about 700mm to 2700mm. In addition, the length dimension of the thinner curved portion 21c in the printing direction is about 0mm to 100mm (when the curved portion 21c is not provided, the length = 0mm), and the length dimension of the clamp portion 21d in the printing direction is set to about 15mm to 40mm. In addition, the positioning holes 25 provided at the ends of the printing plate sheet 21 for the positioning pins 4 of the bench vises 3A and 3B to pass through also depend on the size of the printing plate sheet 21, but usually, at least 5 positioning holes 25 are provided, and in more cases, more than 30 positioning holes are provided.

[0057] On the other hand, the base sheet 22 provided on the back side of the printing plate sheet 21 in order to reinforce the printing plate sheet 21 is formed by laminating one or more layers of a relatively strong sheet (usually also including a form called "film"). In this example, a two-layer sheet made of polyethylene terephthalate (PET) is used, but as the material of the sheet, in addition to the above-mentioned PET, other resins such as polyvinyl chloride (PVC) can be used. In addition, metals such as aluminum and stainless steel (SUS) can also be used.

[0058] In addition, as with the case of the printing plate sheet 21, it is preferable to select a material that is not affected by the types of ink, plate cleaning fluid, etc. used in the manufacturing process of liquid crystal, organic EL, organic TFT, etc., as for the material constituting the above-mentioned base material sheet 22.

[0059] In addition, the vises 3A and 3B (returned to the position where the printing plate 20 formed of the printing plate sheet 21 and the base sheet 22) are installed at both ends in the printing direction of the printing plate 20. Figure 1 ), as already stated, for Figure 9 In addition, in order to prevent the printing direction of the printing plate 20 from being offset, the flat surface portion 6a of the front side member 6 of the bench vise 3A, 3B for pressing the front side of the printing plate sheet 21, the bottom surface portion 6c for fastening the back side member 7 via the base sheet 22, and the flat surface portion 7a of the back side member 7 may be formed with a wavy, serrated or rib-like concave and convex shape in a direction perpendicular to the printing direction.

[0060] Next, an example of a method of integrally laminating the printing plate sheet 21 and the base sheet 22 to form the printing plate 20 and attaching the vises 3A and 3B to both ends of the printing plate 20 to form a printing plate support will be briefly described.

[0061] First, prepare a forming die (inverting die) capable of transferring the uneven shape such as the printing convex portion 21a of the printing plate sheet 21 for the printing plate 20, and place it on a stable horizontal plate or the like. Then, inject a liquid photosensitive resin composition for forming a printing plate, which is the material of the printing plate sheet 21, into the above-mentioned forming die, cover a transparent base sheet 22 (an intermediate with a size larger than the target size) on its horizontal surface and make it fit closely. In this state, irradiate the curing radiation such as ultraviolet rays from above the base sheet 22 (intermediate) to cure the photosensitive resin composition, and then perform demolding. Thus, a printing plate 20 (intermediate) in which the above-mentioned base sheet 22 (intermediate) is laminated on the back side of the printing plate sheet 21 and integrated can be obtained. In addition, in order to complete the curing completely, heating or the like can be performed separately.

[0062] Then, cut the base sheet 22 (intermediate) in the obtained printing plate 20 (intermediate) into a specified size such that both end portions in the printing direction protrude outward from both end portions of the printing plate sheet 21, and form through holes 31 at specified positions in the protruding portions 30 of the base sheet 22 (refer to Figure 2 ), and remove the unnecessary parts. In this way, the target printing plate 20 (finished product) can be obtained.

[0063] Next, vise 3A and 3B are respectively installed at both end portions in the printing direction of the obtained printing plate 20. In the installation operation, first, insert the positioning pins 4 provided on the back side members 7 of the vises 3A and 3B into the positioning holes 25 of the printing plate 20 respectively, and place the clip portion 21d of the printing plate 20 and the protruding portions 30 of the end portions of the base sheet 22 that protrude outward from the end portions of the printing plate sheet 21 on the flat surface portion 7a of the back side member 7 at appropriate positions. At this time, the through holes 31 of the protruding portions 30 of the base sheet 22 are arranged overlappingly on the threaded holes 9 of the back side member 7.

[0064] Then, in a state where both end portions of the printing plate 20 are positioned on and engaged with the back side members 7 of the vises 3A and 3B, overlap the front side member 6 on the back side members 7 of the vises 3A and 3B in a manner of clamping the printing plate 20. Then, by screwing the front side member 6 toward the back side member 7 side using the threaded member 8, the target printing plate support can be obtained.

[0065] For the printing plate support obtained in this way, as in the past, it is, for example, assembled to Figure 7 the shown flexographic printing press and can be used for flexographic printing.

[0066] With this printing plate support, in the engaging portion between the conventional positioning hole 25 and the positioning pin 4, the end portion of the base material sheet 22 that is integrally locked with the end portion of the printing plate sheet 21 and has a relatively high degree of freedom is locked into the fastening and fixing portions of the vises 3A and 3B and fixed. Therefore, in the base material sheet 22, a situation where an excessive force is applied to the periphery of the positioning hole 25 and deformation occurs does not occur. In addition, it is not necessary to forcibly lock the end portion of the relatively soft printing plate sheet 21, so that deformation such as elongation and distortion does not occur in this portion.

[0067] Therefore, the entire printing plate 20 is not likely to elongate or shift, and fine printing patterns can be repeatedly printed with good reproducibility. Moreover, with this structure, the flat surface portion 6a of the front side member 6 of the vises 3A and 3B presses the front surface of the end portion of the printing plate sheet 21, and similarly, its end surface 21f faces the stepped portion 6b of the front side member 6. Therefore, the front side member 6 has a structure for protecting the end portion of the printing plate sheet 21 from the outside. Also, no extra parts are added to the printing plate 20 and the vises 3A and 3B. As the vises 3A and 3B, conventional vises can be directly installed. Therefore, it has the advantages that the installation operation of the vises 3A and 3B to the printing plate 20 is simple and the versatility is relatively high.

[0068] In addition, in the printing plate support of the present invention, it is important that the protruding portion 30 of the base material sheet 22 protruding from the end portion of the printing plate sheet 21 is clamped into the fastening and fixing portion between the front side member 6 and the back side member 7 of the vises 3A and 3B, and the protruding portion 30 needs to be sufficiently locked by the threaded member 8 locked into this portion. Therefore, it is desirable that the edge 30a of the protruding portion 30 is flush with the edge 6d of the front side member 6 or slightly protrudes outward from the edge 6d of the front side member 6. The dimension of this protruding width P (refer to Figure 1 ) also depends on the size of the printing plate 20, but generally, it is preferably 0 mm to 20 mm, and particularly preferably 0 mm to 10 mm. That is, if the protruding width P is too narrow, there is a risk that the fastening of the vises 3A and 3B to the base material sheet 22 becomes insufficient. On the contrary, if the protruding width P is too large, there is a risk that it is difficult to perform the operation when installing this printing plate support on the printing plate cylinder by means of the vises 3A and 3B (refer to Figure 7 ), so it is not ideal.

[0069] In addition, in the printing plate support of the present invention, a through hole 31 through which a threaded member 8 serving as a fastening member penetrates is formed in the protruding portion 30 of the base material sheet 22. When the diameter D of the threaded portion of the threaded member 8 is, for example, about 2 mm to 10 mm, the diameter H of the through hole 31 of the protruding portion 30 is preferably set to a size that is about 0.3 mm to 8 mm larger than the diameter D of the threaded portion. Among them, it is particularly preferably set to a size that is about 0.5 mm to 5 mm larger than the diameter D of the threaded portion. That is, if the through hole 31 through which the threaded member 8 penetrates is set too large with respect to the threaded portion of the threaded member 8, the locking area of the protruding portion 30 with respect to the vises 3A and 3B becomes smaller, and there is a risk that the locking force on the base material sheet 22 cannot be fully reflected, which is not ideal. In addition, if the through hole 31 is too small, it is difficult to lock the threaded member 8, and there is a risk that its workability is impaired, which is also not ideal.

[0070] Moreover, the diameter J (refer to Figure 1 , not shown in the figure with reference numeral J) of the through hole 50 provided in the front side member 6 for fastening the protruding portion 30 of the base material sheet 22 from above and through which the threaded member 8 penetrates and the diameter H of the through hole 31 of the base material sheet 22 are preferably set to the relationship shown in the following formula (1).

[0071] (J - H) ≤ 3 mm...(1)

[0072] That is, the opening peripheral portion of the through hole 50 on the front side member 6 side not only serves to hold the opening peripheral portion of the through hole 31 on the base material sheet 22 side from above and keep it stationary, but also serves to prevent an excessive force from being applied to the opening peripheral portion of the through hole 31 and causing this portion to be lifted, elongated, and deformed. Therefore, it is desirable to firmly hold the opening peripheral portion of the through hole 31 by the opening peripheral portion of the through hole 50 on the front side member 6 side. Therefore, for example, the diameter J of the through hole 50 on the front side member 6 side is preferably set to be smaller than the diameter H of the through hole 31 on the base material sheet 22 side. On the other hand, when the diameter J increases to an extent that exceeds 3 mm compared to the diameter H, there is a risk that the degree of freedom of the opening peripheral portion of the through hole 31 on the base material sheet 22 side becomes larger and deformation occurs in this portion, which is not ideal. If this relationship is expressed by an equation, it becomes the above formula (1).

[0073] However, considering the balance between the size of the threaded member 8 penetrating through these through holes 50 and 31 and the setting of how much larger the through hole 31 on the base material sheet 22 side is set compared to the threaded portion, the diameter J of the through hole 50 on the front side member 6 side is preferably at most 5 mm smaller than the diameter H of the through hole 31 on the base material sheet 22 side.

[0074] In addition, in the printing plate support of the present invention, the above-mentioned base material sheet 22 reinforces the printing plate sheet 21 from the back side, and the protruding portion 30 protruding outward thereof is clamped by the vises 3A and 3B, thereby serving to fix the whole of the printing plate 20 to suppress elongation and displacement. Although it has flexibility, a certain degree of strength and quality stability can still be achieved. Therefore, the thickness of the base material sheet 22 is preferably 0.1 mm to 1.2 mm, and particularly preferably 0.1 mm to 0.8 mm. That is, if the thickness of the base material sheet 22 is too thin, there is a risk that the strength of the clamping portion when the protruding portion 30 is clamped into the vises 3A and 3B becomes weak. On the contrary, if the base material sheet 22 is too thick, there is a risk of impairing the flexibility of the whole printing plate, which is not desirable.

[0075] In addition, in the above example, as Figure 1 , Figure 2 shown, a positioning hole 25 is provided on the end side of the printing plate 20, and a through hole 31 for firmly fixing the printing plate 20 is provided at a position further on the end side than the positioning hole 25. The printing plate 20 is clamped by the front side member 6 having a stepped portion 6b and the back side member 7 having a positioning pin 4 and a threaded hole 9. However, as the front side member 6, a plate-shaped member without the stepped portion 6b can also be used.

[0076] For example, as Figure 3 shown, the positioning hole 25 is not provided on the printing plate 20, and the positioning pin 4 is not provided on the back side member 7'. The through hole 31 provided in the protruding portion 30 of the base material sheet 22 and the threaded hole 9 provided in the back side member 7' are aligned with each other for positioning. In this state, the plate-shaped front side member 6' is placed from above and fixed with a threaded member 8, whereby the positioning and fixing of the printing plate 20 can be performed at one time.

[0077] With this structure, as the front side member 6', a flat plate-shaped member can be used. Therefore, the overall structure is simple and is preferable.

[0078] In addition, in the Figure 3 structure, it may also be that, in the protruding portion 30 of the base material sheet 22, a positioning hole (corresponding to Figure 2 the positioning hole 25) is provided separately from the through hole 31 through which the threaded member 8 passes, and a positioning pin (corresponding to Figure 1 the positioning pin 4) is provided on the back side member 7' side. Moreover, a through hole for the positioning pin to pass through is also provided on the front side member 6'. Thus, first, positioning is performed by engaging the positioning pin of the back side member 7' with the positioning hole of the base material sheet 22. In this state, the front side member 6' is placed from above and fixed with a threaded member 8. In this structure, a flat plate-shaped front side member 6' can also be used. Therefore, the structure is relatively simple and is preferable.

[0079] Further, in the above series of embodiments, as the fixing member for performing fastening and fixing in the vise 3A and 3B, screw fixing using the screw member 8 and the screw hole 9 is illustrated, but the fixing member is not limited thereto, and various fixing members such as a clamping mechanism using a spring can be used.

[0080] In addition, in the above series of embodiments, in the fixing portion of the printing plate 20 realized by the left and right vises 3A and 3B, the structure of the present invention is applied to both ends in the printing direction (the structure in which the protruding portion 30 is extended and provided on the base material sheet 22 and the protruding portion 30 is locked and fixed by the vises 3A and 3B), but the structure of the present invention is not necessarily applied to both ends, and the structure of the present invention can be applied to at least one end. Further, in the case of applying to any one end, from the viewpoint of the effect, it is more preferable to apply to the end on the upstream side (the chuck head side) in the printing direction.

[0081]

Example

[0082] Next, the embodiments of the present invention will be described together with the comparative examples. That is, first, the example products and the comparative example products were prepared as follows.

[0083] [Example 1]

[0084] A printing plate support as shown in Figure 1 was produced. The detailed structure is as described below. In addition, alignment marks 40 and 41 were formed on the front surface of the printing plate 20, that is, on the upstream side and the downstream side of the front surface of the printing plate sheet 21, as schematically shown in Figure 4 .

[0085] <Printing plate sheet 21>

[0086] Material: Butadiene acrylate rubber (Shore hardness 55 degrees)

[0087] Thickness of the chuck portion 21d: 2.36 mm

[0088] Size of the printing plate sheet 21: Length in the printing direction × Width = 100 mm × 50 mm

[0089] <Base material sheet 22>

[0090] Material: PET (two-layer laminated PET sheet)

[0091] Thickness: 0.76 mm

[0092] Size of the base material sheet 22: Length in the printing direction × Width = 150 mm × 50 mm

[0093] Length of the protruding portion 30 in the printing direction: 5 mm

[0094] The length P by which the edge 30a of the protruding portion 30 protrudes from the edge 6d of the front-side member 6: 25 mm

[0095] The diameter H of the through-hole 31 through which the threaded member 8 passes: 7.5 mm

[0096] <Bench vises 3A, 3B>

[0097] Material: Stainless steel

[0098] The thread diameter D of the threaded member 8: 4.0 mm

[0099] [Example 2]

[0100] The length of the base material sheet 22 in the printing direction was shortened in such a manner that the edge 30a of the protruding portion 30 of the base material sheet 22 was flush with the edge 6d of the front-side member 6 of the bench vises 3A, 3B. Other than this, a printing plate support identical to that of Example 1 was obtained.

[0101] [Example 3]

[0102] The length of the base material sheet 22 in the printing direction was lengthened in such a manner that the edge 30a of the protruding portion 30 of the base material sheet 22 protruded 10 mm outward from the edge 6d of the front-side member 6 of the bench vises 3A, 3B. Other than this, a printing plate support identical to that of Example 1 was obtained.

[0103] [Example 4]

[0104] The diameter H of the through-hole 31 of the protruding portion 30 of the base material sheet 22 was set to 8.0 mm. Other than this, a printing plate support identical to that of Example 1 was obtained.

[0105] [Example 5]

[0106] The diameter H of the through-hole 31 of the protruding portion 30 of the base material sheet 22 was set to 11 mm. Other than this, a printing plate support identical to that of Example 1 was obtained.

[0107] [Comparative Example 1]

[0108] A printing plate support having the structure shown in Figure 9 was fabricated. In this case, in the printing plate 10, the end of the printing plate sheet 1 and the end of the base material sheet 2 were flush, and no protruding portion 30 as in Example 1 was provided. The other structure was the same as that of Example 1.

[0109] <Evaluation>

[0110] The products of the above Example 1 and Comparative Example 1 were respectively assembled to Figure 7The plate cylinder of the rotary flexible printing press shown repeats printing on the object to be printed (paper), and every time a specified number of prints are made, the displacements of the alignment marks 40 and 41 in the printing plate support are measured. The results are shown in Figure 5 (Example 1) and Figure 6 (Comparative Example 1).

[0111] In addition, the displacement of the upstream alignment mark 40 and the displacement of the downstream alignment mark 41 represent the offsets from their respective initial positions. And the difference between the two displacements represents the distance by which the printing plate 20 itself elongates between the two alignment marks 40 and 41.

[0112] From the above Figure 5 、 Figure 6 results, the displacements of the alignment marks 40 and 41 of the product of Example 1 are small, and the displacements of each other overlap, so it can be seen that no elongation occurs between the two. In contrast, the displacements of the alignment marks 40 and 41 of the product of Comparative Example 1 are large, and it can be seen that elongation occurs to a large extent between the two. Therefore, it can be considered that if the number of printed sheets increases, offsets will occur during printing and accurate printing cannot be reproduced.

[0113] In addition, for the products of Example 2 to Example 5 above, printing was also repeated in the same manner, and the displacements of the alignment marks 40 and 41 were measured. As a result, it can be seen that although the displacements are slightly larger than those of the product of Example 1, no elongation occurs between the two, and the printing reproducibility is very excellent compared with the product of Comparative Example 1.

[0114] In addition, in the above embodiments, specific forms of the present invention are shown, but the above embodiments are merely illustrative and cannot be construed in a limiting sense. Various modifications obvious to those skilled in the art are included in the scope of the present invention.

[0115] Industrial applicability

[0116] Although the flexible printing plate support of the present invention has a simple structure, it is not easy to cause elongation and offset in the printing plate, and can maintain high printing reproducibility for a long time. Therefore, it can be used for fine printing of electrode layers, sealants, masking agents, etc. provided on substrates such as liquid crystals, organic ELs, and organic TFTs.

Claims

1. A flexible printing plate support body, which includes a flexible printing plate; and a vise that clamps and supports the end portions in the printing direction of the flexible printing plate from the front side and the back side, The flexible printing plate support body is characterized in that, The flexible printing plate is composed of a printing plate sheet and a base material sheet. The printing plate sheet has convex portions for printing formed on the front side, and the base material sheet is integrally provided on the back side of the printing plate sheet to strengthen the printing plate sheet, The vise includes: A front side member disposed on the front side of the end portion of the flexible printing plate; A back side member disposed on the back side of the end portion of the flexible printing plate; and A fixing member that tightly fixes both the front side member and the back side member in a state where the flexible printing plate is clamped between the front side member and the back side member, At the end portion in the printing direction of the flexible printing plate, the end portion of the base material sheet protrudes outward more than the end portion of the printing plate sheet, The front side member of the vise has: a first flat portion for pressing the front of the end portion of the printing plate sheet; a second flat portion for pressing the front of the protruding portion of the base material sheet that protrudes from the end portion of the printing plate sheet; and a step portion that faces the end face of the end portion of the printing plate sheet, Between the front side member and the back side member of the vise, the protruding portion of the base material sheet is fixed in a clamped state.

2. The flexible printing plate support body according to claim 1, wherein, The edge of the protruding portion of the base material sheet protrudes 0 mm to 10 mm in the printing direction from the edge on the side where the base material sheet protrudes of the front side member of the vise when viewed from above.

3. The flexible printing plate support body according to claim 1 or 2, wherein, The fixing member of the vise is composed of a threaded hole provided in either the front side member or the back side member, a through hole provided in the other of the front side member and the back side member, and a threaded member screwed into the threaded hole. A through hole for the threaded member to pass through is formed in the protruding portion of the base material sheet. The diameter D of the threaded portion of the threaded member is 2 mm to 10 mm, and the diameter H of the through hole of the base material sheet is set to a size that is 0.3 mm to 8 mm larger than the diameter D of the threaded portion.

4. The flexible printing plate support body according to claim 1 or 2, wherein, The fixing member of the vise is composed of a threaded hole provided in either the front side member or the back side member, a through hole provided in the other of the front side member and the back side member, and a threaded member screwed into the threaded hole. A through hole for the threaded member to pass through is formed in the protruding portion of the base material sheet. When the diameter of the through hole provided in the other of the front side member and the back side member is set as J, the relationship between the size of the diameter J and the diameter H of the through hole of the base material sheet is set to the relationship shown in the following formula (1), (J - H) ≤ 3 mm (1).

5. The flexible printing plate support body according to claim 1 or 2, wherein, The thickness of the base material sheet is 0.1 mm to 1.2 mm.

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