JP2012011667A - Flexographic printing apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a flexographic printing apparatus that can achieve a continuous ink transfer even in an irregular-shaped step difference part.SOLUTION: The flexographic printing apparatus includes a flexo plate 20 with a flexo plate projecting portion 21, and conducts printing by striding an electrode 32 and a smooth surface 31, which is a recessed portion in the projecting portion 21 of the flexo plate 20 in relative to a workpiece 30 where the electrode 32, which is an projecting portion. The flexo plate projecting portion 21 is composed of the belt-like projecting portion 22 that projects like a belt. In the belt-like projecting portion 22, the band width of a transfer portion 22a to a step portion 32a of the boundary between the smooth surface 31 of a workpiece 2 and the electrode 32 is wider than that of a transfer portion 22b to the smooth surface of the workpiece 30.

Description

  The present invention relates to a flexographic printing apparatus provided with a flexographic plate having a flexible flexographic convex portion used for printing in the production of a liquid crystal display panel or a semiconductor device made of glass or ceramic that is easily broken, for example. The present invention relates to a flexographic printing apparatus that performs relief printing on a substrate to be printed on which concave portions and convex portions exist.

  Current printing methods include letterpress printing using a relief plate as a plate, offset printing using a flat plate as a plate, gravure printing using a concave plate as a plate, screen printing using a hole plate as a plate, and an electronic plate as a plate. There are inkjet printings to use.

  Here, letterpress printing is roughly divided into general letterpress printing and flexographic printing. In general letterpress printing, letterpress printing using a hard plate such as a letterpress plate or a lead plate is known as a letterpress plate. On the other hand, flexographic printing is characterized by using a flexible (flexible) elastic plate (synthetic resin or rubber plate) and having a lower “printing pressure” than general relief printing. For this reason, flexographic printing exhibits high print reproducibility in multiple colors on stretchy thin materials such as paper (thick paper, cardboard, etc.) with poor smoothness and films, cloths and nonwoven fabrics. In addition, we are good at very thin and uniform solid printing, and it is possible to further improve accuracy by applying various resins and chemicals repeatedly.

  In addition, as described above, since flexographic printing uses a flexible elastic relief plate such as a synthetic resin or rubber plate as a plate, printing can be performed even on a highly rigid flat plate such as glass or ceramic. . For this reason, flexographic printing has come to be used for application of alignment films of liquid crystal display panels made of glass or ceramic, production of color filters, and the like.

  For example, Patent Document 1 is known as a conventional flexographic printing apparatus used for this type of liquid crystal display panel. Patent Document 1 discloses changing the size of minute unevenness provided on a convex portion in order to make the transfer ink amount (film thickness) constant. Specifically, as shown in FIGS. 7A and 7B, a convex portion 110 is formed on the base portion 101 of the resin relief plate 100, and the convex portion 110 has a micro convex portion 111... And a micro concave portion 112. And are formed. And these micro recessed parts 112 ... are shallow as it becomes a peripheral part. As a result, the deeper the recess, the more transfer ink can be stored, so that the amount of transfer ink at the center is increased and the ink spreads to the periphery to realize application with a constant film thickness.

  That is, when a coating liquid is printed on a printing medium using such a resin relief plate 100, the amount of coating liquid retained is smaller in the peripheral portion of the convex portion 110 than in the central portion of the convex portion 110. The thickness of the coating liquid printed on the substrate is thick at the center and thin at the periphery. However, due to the surface tension of the coating liquid, the coating liquid is drawn to the periphery, and as a result, a coating liquid with a uniform thickness is printed. Is obtained.

Japanese Patent Laid-Open No. 11-221976 (released on August 17, 1999)

  By the way, in the flexographic printing apparatus used for the conventional liquid crystal display panel, for example, a functional material such as a polyimide resin is printed as a transfer ink in order to solid-print an alignment film on a smooth glass plate as a substrate to be printed. Had been used in case.

  However, when there are concave portions and convex portions such as electrodes on a smooth glass plate that is a substrate to be printed, printing is performed by transferring the pressure across the electrode that is the convex portion and the smooth glass plate that is the concave portion. In this case, there is a problem that an area where ink cannot be transferred is generated near the wall of the step between the electrode and the smooth glass plate.

  That is, in a flexographic printing apparatus used for a conventional liquid crystal display panel, printing on a substrate to be printed having an uneven portion as described above has not been performed. Therefore, even in Patent Document 1, there is no description or suggestion of such a problem and a configuration for solving the problem.

  The present invention has been made in view of the above-described conventional problems, and an object of the present invention is to provide a flexographic printing apparatus capable of realizing ink transfer that is not interrupted even in a stepped portion of a substrate to be printed in which concave portions and convex portions exist. There is to do.

  In order to solve the above-described problems, the flexographic printing apparatus of the present invention includes a flexographic plate having a flexible flexographic plate convex portion, and the flexographic plate convex portion projects from the substrate to be printed on which the concave portion and the convex portion exist. In a flexographic printing apparatus that performs printing by pressing and transferring over a portion and a concave portion, the flexographic plate convex portion is composed of a belt-shaped convex plate portion protruding in a belt shape, and the belt-shaped convex plate portion is formed on the substrate to be printed. The band width of the transfer portion to the step portion at the boundary between the concave portion and the convex portion is characterized by being wider than the band width of the transfer portion to the concave portion of the substrate to be printed.

  According to the above invention, the flexographic printing apparatus performs printing by pressing and transferring the flexographic printing plate between the convex portion and the concave portion with the flexible flexographic convex portion of the flexographic plate to the substrate to be printed on which the concave portion and the convex portion exist. Do.

  In this case, an area where ink cannot be transferred is generated near the wall of the step portion at the boundary between the concave portion and the convex portion. This is because the convex pattern of the plate does not deform accurately along the stepped portion.

  Therefore, in the present invention, first, the flexographic convex portion is composed of a strip-shaped convex portion protruding in a strip shape. For this reason, since the flexible flexographic convex portion has a small contact area with the substrate to be printed, the strip-shaped convex portion is easily crushed even at the step portion of the boundary between the concave portion and the convex portion. It is possible to reduce an area where ink cannot be transferred in the vicinity of the wall of the step portion at the boundary between the concave portion and the convex portion.

  Furthermore, in the present invention, the band-shaped relief printing plate has a band width of the transfer portion to the step portion at the boundary between the concave portion and the convex portion of the substrate to be printed larger than the band width of the transfer portion to the concave portion of the substrate to be printed. It has become. For this reason, the amount of ink applied to the surface of the belt-like relief plate has a predetermined fixed contact angle due to the surface tension of the ink. As a result, when the width of the belt-like relief plate is thick, a large amount of ink can be held, and the occurrence of breaks at the stepped portion can be prevented.

  Therefore, it is possible to provide a flexographic printing apparatus capable of realizing ink transfer that is not interrupted even in a stepped portion of a substrate to be printed in which concave portions and convex portions exist.

  In the flexographic printing apparatus of the present invention, it is preferable that a concavo-convex pattern comprising a plurality of concavo-convex patterns is formed at least on the stepped portion of the strip-shaped relief plate and on the surface of the strip-shaped relief portion at the transfer portion to the periphery.

  As a result, since the transfer ink can be stored in the concave portions of the concave / convex pattern at least on the surface of the belt-like relief printing portion at the step portion and the periphery thereof, the amount of transfer ink at the transfer portion to the step portion and the periphery thereof is increased. be able to.

  Therefore, it is possible to provide a flexographic printing apparatus that can realize ink transfer that is not interrupted even at a stepped portion.

  In the flexographic printing apparatus of the present invention, the belt-shaped relief plate has a concave-convex pattern formed of a plurality of irregularities formed on the surface of the belt-shaped relief plate at the transfer location to the concave portion of the substrate to be printed. The density of the concavo-convex pattern consisting of a plurality of concavo-convex patterns formed on the surface of the stepped portion and the belt-like relief printing portion at the periphery thereof is formed on the surface of the belt-like relief printing portion at the transfer portion to the concave portion of the substrate to be printed. It is preferably higher than the density of the concavo-convex pattern comprising a plurality of concavo-convex patterns.

  In other words, the belt-like relief plate has a concave-convex pattern formed of a plurality of irregularities on the surface of the belt-like relief plate at the step portion and the periphery thereof, and the belt-like shape of the transfer portion to the concave portion of the substrate to be printed. A concavo-convex pattern composed of a plurality of concavo-convex portions is also formed on the surface of the relief plate. As a result, since the transfer ink can be stored in the concave portion of the concave / convex pattern formed on the entire surface of the belt-shaped relief plate portion, the amount of transfer ink in the entire region of the belt-like relief plate surface can be increased.

  In particular, the density of the concavo-convex pattern composed of a plurality of concavo-convex patterns formed on the surface of the belt-shaped relief printing portion at the step portion in the belt-like relief printing portion and the periphery thereof, the belt-like relief printing portion at the transfer location to the depression of the substrate to be printed Since the density of the concavo-convex pattern composed of a plurality of concavo-convex patterns formed on the surface is higher, the amount of ink transferred to the step portion can be increased.

  In the flexographic printing apparatus of the present invention, the printed substrate is provided with a plurality of convex portions arranged in an array, and the belt-shaped relief plate portion of the flexographic plate convex portion is also provided at a plurality of locations on the printed substrate. The belt-like relief printing plate is provided in an array corresponding to the convex portions, and the belt-like relief plate is closed in a frame shape so as to perform printing closed in a frame shape across each convex portion provided on the substrate to be printed. It can be made up of things.

  Thereby, since the belt-like relief printing plate is formed by the belt being closed in a frame shape, a plurality of prints closed in a frame shape traversing the plurality of protrusions provided on the substrate to be printed can be performed simultaneously. Further, in the present invention, it is possible to eliminate the region where the ink at the step portion cannot be transferred. For this reason, the printed material can completely block the in-frame region and the out-of-frame region, and in the subsequent process, the in-frame region can be filled with liquid.

  In the flexographic printing apparatus of the present invention, it is preferable that the belt-shaped relief printing portion is formed by a belt having an annular shape.

  As a result, when printing is performed in a frame shape, if a rectangular frame is used, durability around the four corners during press transfer is a problem. And averaging can be achieved. Therefore, the durability of the belt-like relief plate portion is improved.

  In the flexographic printing apparatus of the present invention, as described above, the flexographic plate convex portion is composed of a belt-shaped convex plate portion protruding in a strip shape, and the belt-shaped convex plate portion is a step at the boundary between the concave portion and the convex portion of the substrate to be printed. The band width of the transfer portion to the portion is larger than the band width of the transfer portion to the concave portion of the substrate to be printed.

  Therefore, there is an effect of providing a flexographic printing apparatus capable of realizing ink transfer that is not interrupted even in a stepped portion of a substrate to be printed in which concave portions and convex portions exist.

(A) shows one Embodiment of the flexographic printing apparatus in this invention, Comprising: It is a top view which shows the structure of a flexographic plate, (b) is a top view which shows the workpiece | work printed across the electrode. FIG. 4C is a plan view of a principal part showing a boundary between an electrode and a smooth surface in a work printed across the electrode. It is a schematic block diagram which shows the said flexographic printing apparatus. (A) is a front view showing the ink attached to the surface of the belt-like relief printing portion when the width of the belt-like relief printing portion is thick, and (b) is the front view showing the ink on the surface of the belt-like relief printing portion when the width of the belt-like relief printing portion is thin. FIG. (A) is a top view which shows the structure of the modification of the said flexographic plate, (b) is a top view which shows the corresponding positional relationship of an electrode and a workpiece | work. (A) shows other embodiment of the flexographic printing apparatus in this invention, Comprising: It is a top view which shows the structure of the flexographic plate provided with the some strip | belt-shaped relief printing part, (b) is an electrode arranged It is a top view which shows the workpiece | work provided in multiple numbers, (c) is a top view which shows the workpiece | work printed across the electrode. It is a top view which shows the detailed structure of the said strip-shaped relief part. (A) shows the flexographic printing apparatus of a comparative example, Comprising: It is a top view which shows the structure of a flexographic plate, (b) is a top view which shows the workpiece | work printed across the electrode, (c) FIG. 3 is a plan view of a principal part showing a boundary between an electrode and a smooth surface in a work printed across the electrode. (A) shows the flexographic printing apparatus of the comparative example, and is a cross-sectional view showing a flexographic plate pressing a work provided with an electrode, and (b) is a cross-section showing a work printed across the electrode. It is a figure, (c) is a principal part top view which shows the boundary of the electrode and smooth surface in the workpiece | work printed across the electrode. (A) shows the conventional flexographic printing apparatus, Comprising: It is a top view which shows the structure of a flexographic plate, (b) is sectional drawing which shows the structure of the principal part of (a).

[Embodiment 1]
One embodiment of the present invention will be described below with reference to FIGS. 1 to 3 and FIGS. 7 and 8.

  As shown in FIG. 2, the flexographic printing apparatus 10 according to the present embodiment includes a plate cylinder 11 formed of a cylinder, and a flexographic plate 20 fixed to the surface of the plate cylinder 11. In the flexographic printing apparatus 10, printing can be performed on the work 30 by moving the plate cylinder 11 and the stage 1 while synchronizing the work so that the flexographic printing plate 20 is pressed against the work 30 as a printing substrate placed on the stage 1. It is like that.

  The flexographic printing apparatus 10 is provided with an anilox roller for adhering ink to the flexographic plate 20, a doctor blade for uniformly applying ink to the anilox roller, and an ink dropping mechanism. Is omitted.

  In the present embodiment, the work 30 is a liquid crystal display panel made of, for example, glass or ceramic, and is easily broken. Further, the workpiece 30 has a convex portion on a smooth surface such as glass. Specifically, in the present embodiment, as shown in FIG. 1B, the workpiece 30 is provided with a substantially rectangular parallelepiped electrode 32 on a smooth surface 31 thereof. Therefore, the electrode 32 constitutes the convex portion of the present invention, and the smooth surface 31 constitutes the concave portion of the present invention. The electrode 32 has a width of, for example, 50 μm to 1 mm, and a length of, for example, 2 mm. The height of the electrode 32 is, for example, 10 μm. In addition, these dimensions are illustrations and are not necessarily limited thereto. For example, the length of the electrode 32 may be shorter or longer than 2 mm, and may be 1 m, for example.

  In this embodiment, as shown in FIG. 1B, printing for a functional material such as a mask closed in a frame shape that protrudes from the smooth surface 31 of the workpiece 30 and crosses one electrode 32 provided thereon. The purpose is to do.

  By the way, in the flexographic printing apparatus 10, when the work 30 is easily broken as in the present embodiment, it is desirable to make the flexographic relief plate portion of the flexographic plate 20 as thin as possible to prevent damage. Accordingly, a thin transfer pattern with a reduced contact area is effective particularly in an application where a functional material is used to form a boundary with an untransferred area using transfer ink.

  Here, in the flexographic printing apparatus 10 that transfers and prints the ink of the flexographic plate 20 onto the work 30, the flexographic plate 20 is pressed against the work 30 and transferred. In this case, in order to transfer the transfer ink uniformly and without interruption, it is necessary to press the flexographic relief plate portion of the flexographic plate 20 against the work 30 while crushing a predetermined amount.

  The flexographic printing plate 20 of the flexographic printing apparatus 10 according to the present embodiment is made of, for example, a resin such as silicone resin, polyethylene resin, polyethylene terephthalate resin, polypropylene resin, or rubber such as silicone rubber, and has flexibility and flexibility. Therefore, it is possible to use glass, a ceramic substrate, or the like for the work 30. However, the load applied to the workpiece 30 during transfer is large, and there is a concern that the workpiece 30 may be broken or the performance of the workpiece 30 may be degraded. Therefore, in the flexographic printing apparatus 10 that performs this type of flexographic printing, it is required to devise a plate shape for the work 30 as a substrate to be printed having concave and convex portions.

  As a countermeasure, it is effective to reduce the load applied to the work 30 by reducing the contact area of the flexographic relief plate 20 with the work 30 at the flexographic relief plate portion. Specifically, for example, as shown in FIG. 7A, the flexible flexographic plate convex portion of the flexographic plate 80 can be composed of a strip-shaped convex plate portion 81 protruding in a strip shape. Thus, by reducing the contact area by forming the flexographic plate protrusions in a belt shape, the load applied to the workpiece 30 can be reduced even with the same amount of plate crushing as in the conventional art. The load is represented by “load = spring constant × crush amount”. Here, the spring constant is obtained by the product of the Young's modulus determined by the material of the flexographic plate 20, the thickness of the flexographic plate 20, and the contact area in contact with the compression direction. Therefore, the spring constant and the load are proportional to the contact area.

  On the other hand, as shown in FIG. 7B, when a convex portion such as an electrode 32 is present on the work 30, for example, a strip-shaped relief plate portion having a uniform thickness of the flexographic plate 80 shown in FIG. 7A. In consideration of printing at 81, even if the height of the electrode 32 is about 10 μm at most, as shown in FIGS. 8A, 8B, and 8C, ink cannot be transferred in the vicinity of the wall of the stepped portion. An area will be generated. This is because the convex pattern of the plate does not deform accurately along the stepped portion.

  That is, when a convex portion such as a wiring pattern such as the electrode 32 exists on the surface of the work 30, the strip-shaped convex portion 81 of the flexographic plate 80 is deformed into the concave and convex portions by pressing during transfer. However, in the stepped portion where the shape changes suddenly, the flexographic plate 80 cannot come into contact with the smooth surface 31 that is the concave portion of the workpiece 30, and the ink is not transferred on the side wall or the bottom portion. For this reason, although the ink spreads to some extent on the surface of the work 30, there is a limit to this, and a portion that is not coated with the ink is formed.

  In this case, any print form that can visually distinguish characters or the like can be read, so there may be no problem even if some untransferred areas exist. However, when a functional material such as a mask or a resist material is used as the transfer ink, this untransferred region becomes a big problem. For example, various defects such as photoresist exposure failure due to transfer interruption, deterioration of electrical characteristics when a conductive material is used, and other external defects are generated.

  Therefore, as shown in FIG. 1A, the flexographic plate 20 of the present embodiment has a flexographic plate convex portion 21, and the flexographic plate convex portion 21 is formed in a rectangular frame shape protruding in a strip shape. It consists of a strip-shaped relief part 22. In addition, as shown in FIGS. 1A and 1B, the belt-like relief plate portion 22 has a belt width of the transfer portion 22a to the step portion 32a at the boundary with the electrode 32 portion which is the convex portion of the workpiece 30. It is thicker than the band width of the transfer portion 22b to the smooth surface 31 which is a concave portion.

  As a result, when printing is performed using the belt-shaped relief printing portion 22, as shown in FIG. 1C, the ink is transferred also in the stepped portion 32a. That is, by increasing the width of the belt-shaped relief plate portion 22, the transfer area and the transfer ink amount can be increased, and the ink is connected to the wall surface and the bottom portion of the stepped portion 32 a by transferring ink to the work 30. Can do.

  Here, as shown in FIGS. 1A, 1B, and 1C, the transfer portion 22a having a large band width is formed before and after the step portion 32a. This is because the misregistration amount in the printing operation is taken into consideration, and the ink transfer without interruption is realized even if the misregistration occurs.

  The principle of the above-described wetting and spreading of the ink to the work 30 will be described with reference to FIGS. FIGS. 3A and 3B show the amount of ink that can be held by the difference in the pattern width of the belt-like relief plate 22, and are sectional views of the belt-like relief plate 22.

  As shown in FIGS. 3A and 3B, the amount of ink applied to the surface of the belt-shaped relief printing portion 22 of the belt-like relief printing portion 22 becomes a predetermined fixed contact angle due to the surface tension of the ink. As a result, the thicker pattern width of the belt-like relief plate 22 can hold a large amount of ink, and a large amount of ink can be supplied to the stepped portion 32a to suppress the occurrence of interruption.

  Here, Table 1 shows the results of experiments on the line width of the belt-like relief plate 22 in order to prevent the transfer ink line to the stepped portion 32a of the work 30 from being interrupted and to prevent the work 30 from cracking. Here, Table 1 is an experiment in which the pattern width of the belt-like relief plate 22 is used as a parameter. “◯” indicates that the stepped portion 32 a can be transferred without interruption, and “×” indicates that the interruption occurs. Is shown. Similarly, “◯” and “×” are evaluated based on whether or not there is a break even at a portion where there is no stepped portion 32a. Further, the step of the step portion 32a in the experiment is 10 μm, and the presence or absence of interruption is evaluated by a microscope.

  As can be seen from Table 1, in order to prevent the work 30 from cracking, it is preferable that the pattern width of the belt-shaped relief printing portion 22 is reduced to 100 μm. However, in the stepped portion 32a, it has been found that the work 30 is interrupted unless it is 150 μm or more. Therefore, it is desirable that the line width of the band-shaped relief printing portion 22 in the stepped portion 32a is about 1.5 times thicker than the normal portion in order to form an uninterrupted pattern.

  Further, in the present embodiment, as shown in FIG. 1B, in order to perform printing closed in a frame shape that protrudes on the smooth surface 31 of the work 30 and crosses one electrode 32, the frame is used as a frame. Consists of a rectangular printing frame 33, for example. As shown in FIG. 1A, the strip-shaped relief 22 for transferring ink to the rectangular printing frame 33 is also formed in a rectangular frame shape.

  That is, in the present embodiment, for example, in the manufacture of a liquid crystal display panel, a step of filling a fluid liquid into the rectangular printing frame 33 is prepared in the next step. For this reason, if there is an unpainted portion at the boundary between the electrode 32 and the smooth surface 31 of the workpiece 30, the fluid liquid is left unfilled when the fluid printing liquid is filled in the rectangular printing frame 33 in the next step. This is not preferable because liquid leaks from the gap formed by. For this purpose, it is necessary that there is no unpainted print at the boundary between the concave portion such as the smooth surface 31 and the convex portion such as the electrode 32.

  Here, in the flexographic printing plate 20 of the present embodiment, as shown in FIGS. 4A, 4B, and 4C, at least the step portion 32a in the belt-like relief plate 22 and the belt-like relief plate of the transfer location 22a to the periphery thereof. It is preferable that a concavo-convex pattern 23 composed of a plurality of minute concavo-convex is formed on the surface.

  Thereby, since the transfer ink can be stored in the concave portion of the uneven pattern 23 at least on the surface of the belt-like relief plate portion of the transfer portion 22a to the step portion 32a and the periphery thereof, the transfer ink of the transfer portion 22a to the step portion 32a and the periphery thereof. The amount can be increased. Therefore, it is possible to provide the flexographic printing apparatus 10 that can realize further uninterrupted ink transfer at the stepped portion 32a.

  That is, the minute uneven pattern 23 on the surface of the belt-like relief portion serves to hold the ink on the surface of the belt-like relief portion. Thereby, the amount of transfer ink can be increased, and the wall surface and the bottom of the stepped portion 32a can be connected with the transfer ink by the ease of wetting and spreading represented by the contact angle due to the mutual relationship between the ink and the work 30.

  Further, in the flexographic printing apparatus 10 of the present embodiment, as shown in FIG. 4A, the belt-like relief portion 22 is provided on the surface of the belt-like relief portion of the transfer portion 22 b to the smooth surface 31 that is a recess of the work 30. Are formed on the surface of the belt-like relief portion of the stepped portion 32a in the belt-like relief plate portion 22 and the transfer portion 22a to the periphery thereof. Is preferably higher than the density of the concavo-convex pattern 23 formed of a plurality of concavo-convex patterns formed on the surface of the belt-like relief printing portion 22b to the smooth surface 31 which is the concave portion of the workpiece 2.

  Thereby, the amount of ink transferred to the step portion 32a can be increased.

  In the present embodiment, the ink to be transferred has a low viscosity and a low surface tension, so that the wetting and spreading to the work 30 is good, and the ink can adhere to the side wall and the bottom of the step portion 32a. . Usually, an ink having a viscosity of 100 cP or more and capable of suppressing wetting and spreading to some extent is selected in order to suppress bleeding of the transfer pattern. However, in the present embodiment, it is desirable to use ink that easily wets and spreads.

  Further, it is preferable to use an ink containing a high boiling point solvent. Since the high-boiling solvent-containing ink can suppress the drying of the ink, it is also effective for good wetting and spreading properties and ink adhesion to the step portion 32a. For example, in the present embodiment, the boiling point of the high boiling point solvent is 165 to 185 ° C.

  As described above, the flexographic printing apparatus 10 according to the present embodiment includes the flexographic printing plate 20 having the flexible flexographic printing plate projection 21, and the flexographic printing plate projection 21 has the electrode 32 on the workpiece 2 having the electrode 32. And printing is performed by pressure transfer across the smooth surface 31.

  In this case, an area where ink cannot be transferred is generated near the wall of the stepped portion 32 a at the boundary between the smooth surface 31 and the electrode 32. This is because the convex pattern of the plate does not accurately deform along the stepped portion.

  Therefore, in the flexographic printing apparatus 10 according to the present embodiment, first, the flexographic printing plate convex portion 21 is composed of a belt-like printing plate portion 22 protruding in a belt shape. For this reason, since the flexible flexographic convex part 21 has a small contact area with the work 30, the belt-like convex part 22 is easily crushed even at the step portion 32a at the boundary between the electrode 32 and the smooth surface 31. As a result, the area where ink cannot be transferred in the vicinity of the wall of the stepped portion 32a at the boundary between the electrode 32 and the smooth surface 31 can be reduced.

  Further, in the present embodiment, the belt-like relief portion 22 has a band width of the transfer portion 22a to the stepped portion 32a at the boundary between the electrode 32 and the smooth surface 31 of the workpiece 30, and a transfer portion to the smooth surface 31 of the workpiece 30. It is thicker than the band width of 22b. For this reason, the amount of ink applied to the surface of the belt-like relief plate has a predetermined fixed contact angle due to the surface tension of the ink. As a result, a larger width of the belt-like relief plate portion 22 can hold a large amount of ink, and can prevent breakage in the stepped portion 32a.

  Therefore, although a high-precision printed shape is not required, in applications where the transfer ink needs to be reliably transferred without interruption, it is possible to realize uninterrupted ink transfer even at the stepped portion 32a of the work 2 where the electrode 32 exists. The flexographic printing apparatus 10 can be provided.

  Further, the ease of cracking of the work 30 is not a problem, and further, the use of flexographic printing can be expanded because the work 30 is not constrained by surface shapes such as concave portions and convex portions.

  Furthermore, in the flexographic printing apparatus 10 according to the present embodiment, a concavo-convex pattern 23 composed of a plurality of minute concavo-convex portions is formed on at least the stepped portion 32a of the strip-shaped relief portion 22 and the surface of the strip-like relief portion of the transfer portion 22a to the periphery thereof. It is preferable.

  Thereby, since the transfer ink can be stored in the concave portion of the uneven pattern 23 at least on the surface of the belt-like relief plate portion of the transfer portion 22a to the step portion 32a and the periphery thereof, the transfer ink of the transfer portion 22a to the step portion 32a and the periphery thereof. The amount can be increased.

  Therefore, it is possible to provide the flexographic printing apparatus 10 that can realize ink transfer that is not interrupted even in the stepped portion 32a.

  Further, in the flexographic printing apparatus 10 according to the present embodiment, the belt-like relief portion 22 is formed with a minute uneven pattern 23 composed of a plurality of unevenness on the surface of the belt-like relief portion of the transfer portion 22 a to the smooth surface 31 of the work 30. Has been. And the density of the uneven | corrugated pattern 23 which consists of several unevenness | corrugation formed in the belt-shaped relief printing part surface of the level | step-difference part 32a in the belt-like relief printing part 22 and its periphery is the density | concentration of the transfer location 22b to the smooth surface 31 of the workpiece | work 30. It is preferable that the density of the concavo-convex pattern 23 composed of a plurality of minute concavo-convex formed on the surface of the belt-like relief plate portion is higher.

  Thereby, since transfer ink can be stored in the recessed part of the uneven | corrugated pattern 23 formed in the whole surface of a strip | belt-shaped letterpress part, the amount of transfer inks of the whole area | region of a strip | belt-shaped letterpress part surface can be increased.

  In particular, the density of the concavo-convex pattern 23 formed of a plurality of concavo-convex patterns formed on the surface of the belt-like relief plate portion of the step portion 32 a and the transfer location 22 a to the periphery of the step-like relief plate 22 is the transfer location 22 b to the smooth surface 31 of the work 30. Since the density of the concavo-convex pattern 23 composed of a plurality of concavo-convex formed on the surface of the belt-like relief plate is higher, the amount of ink transferred to the step portion 32a can be increased.

[Embodiment 2]
The following will describe another embodiment of the present invention with reference to FIGS. The configurations other than those described in the present embodiment are the same as those in the first embodiment. For convenience of explanation, members having the same functions as those shown in the drawings of the first embodiment are given the same reference numerals, and explanation thereof is omitted.

  The flexographic printing apparatus 10 according to the present embodiment is different from the flexographic printing apparatus 10 according to the first embodiment in that it has a plurality of strip-shaped relief plates.

  That is, in the flexographic printing apparatus 10 of the present embodiment, as shown in FIG. 5B, substantially rectangular parallelepiped electrodes 52 are arranged on the smooth surface 51 of the work 50 in an array. Therefore, the electrode 52 forms the convex part of the present invention, and the smooth surface 51 forms the concave part of the present invention. The electrode 52 has a width of, for example, 50 μm to 1 mm and a length of, for example, 2 mm. The height is, for example, 10 μm. In addition, these dimensions are illustrations and are not necessarily limited thereto. For example, the length of the electrode 32 may be shorter or longer than 2 mm, and may be 1 m, for example.

  In this embodiment, as shown in FIG. 5 (c), printing is performed in a closed frame shape that traverses the respective electrodes 52 arranged in an array so as to protrude from the smooth surface 51 of the workpiece 50. The frame is, for example, an annulus 53.

  In the present embodiment, the workpiece 50 is individually divided into chips including the electrodes 52 after printing. For this reason, the workpiece 50 is formed with a dividing groove 54 in a grid pattern.

  That is, in this embodiment, for example, in the manufacture of a semiconductor device, a step of filling a fluid liquid in the ring 53 is prepared in the next step. For this reason, if unpainted portions exist at the boundary between the electrode 52 and the smooth surface 51 of the workpiece 50, when the fluid liquid is filled in the inside of the annular ring 53 in the next step, the fluid liquid is caused by the unpainted portions. Since liquid leaks from the formed gap, it is not preferable. For this purpose, it is required that there is no unprinted print at the boundary between the concave portion such as the smooth surface 51 and the convex portion such as the electrode 52.

  Therefore, the belt-like relief portions 42 in the flexographic printing plate 40 of the present embodiment are also provided in an array corresponding to the electrodes 52 that are the convex portions at a plurality of locations in the work 50. The belt-like relief printing portion 42 is formed of a belt whose shape is closed in a frame shape so as to perform printing closed in a frame shape that crosses each electrode 52 provided on the work 50. Specifically, the belt is formed of an annular ring.

  Accordingly, a plurality of prints closed in a frame shape across the plurality of electrodes 52 provided on the work 50 can be performed simultaneously.

  Further, in the present embodiment, as shown in FIG. 6, each belt-like relief portion 42 has a transfer pattern closed in an annular shape, and the belt width of the transfer portion 42 a to the stepped portion 32 a is a concave portion of the work 50. It is effective to make an elliptical shape thicker than the band width of the transfer portion 42b to the smooth surface 51.

  As a result, it is possible to eliminate a region where the ink on the step portion 32a cannot be transferred. For this reason, the printed material can completely block the in-frame region and the out-of-frame region, and in the subsequent process, the in-frame region can be filled with liquid.

  Further, in the flexographic printing apparatus 10 according to the present embodiment, the belt-like relief plate portion 42 is formed by a belt having a ring-like shape. Therefore, when printing is performed in a frame shape, a rectangular frame is used. The durability around the four corners during press transfer is a problem, but by using an annular shape, the stress can be dispersed and averaged. Therefore, the durability of the belt-like relief portion 42 is improved.

  Also in the present embodiment, in the belt-like relief portion 42, the minute relief pattern 23 composed of a plurality of irregularities is also formed on the surface of the belt-like relief portion of the transfer location 22 a to the smooth surface 51 of the work 50. In addition, the density of the concavo-convex pattern 23 formed of a plurality of concavo-convex patterns formed on the surface of the belt-like relief plate portion of the step portion 32a and the transfer portion 22a to the periphery of the step-like relief plate portion 42 is the transfer location to the smooth surface 31 of the workpiece 30. It is preferable that the density of the concavo-convex pattern 23 formed of a plurality of minute concavo-convex formed on the surface of the belt-like relief plate portion 22b is higher.

  Thereby, since transfer ink can be stored in the recessed part of the uneven | corrugated pattern 23 formed in the whole surface of a strip | belt-shaped letterpress part, the amount of transfer inks of the whole area | region of a strip | belt-shaped letterpress part surface can be increased.

  In particular, the density of the concavo-convex pattern 23 formed of a plurality of concavo-convex patterns formed on the surface of the belt-shaped relief printing portion of the step portion 32 a and the transfer portion 22 a to the periphery of the step-like relief printing portion 42 is transferred to the smooth surface 31 of the workpiece 30. Since the density of the concavo-convex pattern 23 composed of a plurality of concavo-convex formed on the surface of the strip-shaped relief printing portion 22b is higher, the amount of ink transferred to the stepped portion 32a can be increased.

  The flexographic printing apparatus of the present invention includes a flexographic plate having a flexible flexographic plate convex portion, and can be applied to, for example, printing in manufacturing a liquid crystal display panel or semiconductor device made of glass or ceramic that is easily broken. Specifically, for example, a solid coating of an alignment film, a production of a color filter, and the like are possible. In particular, a functional material including an insulating material such as a mask on a substrate to be printed on which a concave portion and a convex portion such as an electrode exist. It can be applied to letterpress printing.

DESCRIPTION OF SYMBOLS 10 Flexo printing apparatus 11 Plate cylinder 20 Flexo plate 21 Flexo plate convex part 22 Strip | belt-shaped convex plate part 22a Transfer part 22b to a level | step difference part Transfer part 23 to a smooth surface Uneven pattern 30 Work 31 Smooth surface (concave part)
32 electrodes (convex)
32a Stepped portion 33 Square printing frame 40 Flexo plate 42 Strip-shaped relief printing portion 42a Transferred portion 42b to stepped portion Transferred portion 50 to smooth surface Workpiece 51 Smooth surface (concave portion)
52 Electrode (convex part)
53 Ring 54 Dividing groove

Claims (5)

Flexographic printing having a flexographic plate having a flexible flexographic convex portion, and printing by printing and pressing the convex portion between the convex portion and the concave portion with respect to the substrate to be printed on which the concave portion and the convex portion exist. In the device
The flexographic convex portion is composed of a strip-shaped convex portion protruding in a strip shape,
In the belt-like relief plate, the band width of the transfer portion to the step portion at the boundary between the concave portion and the convex portion of the substrate to be printed is thicker than the band width of the transfer portion to the concave portion of the substrate to be printed. Flexographic printing device.   2. The flexographic printing apparatus according to claim 1, wherein a concavo-convex pattern comprising a plurality of concavo-convex portions is formed on at least the step portion of the strip-shaped relief portion and the surface of the belt-like relief portion at a transfer position to the periphery thereof. In the belt-like relief plate, a concavo-convex pattern consisting of a plurality of irregularities is also formed on the surface of the belt-like relief plate portion of the transfer portion to the recess of the substrate to be printed,
The density of the concavo-convex pattern consisting of a plurality of concavo-convex patterns formed on the surface of the stepped portion of the band-shaped relief plate and the transfer portion to the periphery thereof is the surface of the band-shaped relief plate portion of the transfer portion to the recess of the substrate to be printed. The flexographic printing apparatus according to claim 2, wherein the density is higher than a density of a concavo-convex pattern comprising a plurality of concavo-convex formed on the substrate. The printed substrate is provided with a plurality of convex portions arranged in an array,
The belt-like relief portion in the flexographic relief is also provided in an array corresponding to the protrusions at a plurality of locations on the printed substrate,
2. The belt-like relief printing plate is formed by a belt-like closed plate so as to perform closed printing in a frame shape across each convex portion provided on the substrate to be printed. The flexographic printing apparatus according to 2 or 3.   5. The flexographic printing apparatus according to claim 4, wherein the belt-shaped relief printing portion is formed by a belt having an annular shape.

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