screen printing

Abstract

This invention provides a screen printing plate with excellent printing accuracy. A screen printing plate, used for screen printing, comprises: a frame; a support screen with its outer periphery fixed to the frame; and a printing screen with its outer periphery fixed to the support screen; characterized in that the support screen is composed of a twill fabric with an n / m ratio, where n and m are each independently an integer greater than or equal to 2.

Description

Technical Field

[0001] This invention relates to screen printing stencils used in precision pattern forming fields such as phosphor printing processes in the manufacture of PDPs (plasma displays), electrode printing in solar cells, liquid crystal sealing printing, via filling printing in substrates, electrode and dielectric printing in capacitors, and resist printing such as TAB (Tape Automated Bonding) and COF (Chip on Flexible). Background Technology

[0002] Typically, a screen printing stencil, as opposed to a mesh screen fixed to a frame under a specified tension, uses a photosensitive resin (emulsion), metal plate, or similar material to form openings of a predetermined shape (the shape of the opening corresponds to the printing pattern). Ink (paste) is then filled into these openings. The ink-filled stencil is configured such that the screen is separated from the printing surface by a certain distance (gap). The screen temporarily contacts the printing surface due to its elastic deformation and immediately separates based on its resilience, thereby applying the ink (paste) containing the printing pattern to the printing surface. To ensure the screen can quickly separate from the printing surface (stencil separation), a certain tension is applied to the screen fixed to the frame.

[0003] In addition to the "full-face tension plate" in which a screen made of synthetic fibers or metal fibers is fixed to the plate frame, "combined screen plates" and "metal masks" are also known as screen printing plates used for this screen printing.

[0004] "Combined screen printing plate" and "metal mask" are screen printing plates that have a support screen fixed to the plate frame on the outer periphery and a printing screen fixed to the support screen on the outer periphery. Regarding "combined screen printing plate," both the support screen and the printing screen are made of fabric; regarding "metal mask," the support screen is made of fabric, but the printing screen is made of metal.

[0005] "Combined screen printing plates" and "metal photomasks" can be manufactured, for example, by attaching a fabric (the material of the support screen) to a printing plate frame, attaching a printing screen to its center, and then removing the central portion of the fabric (the material of the support screen) that overlaps with the printing screen. Regarding "combined screen printing plates," a photosensitive resin is coated onto a printing screen (a screen made of fabric), and then a predetermined area of ​​the coated photosensitive resin is exposed, thereby forming an opening of a predetermined shape for filling the photosensitive resin with ink, for screen printing. On the other hand, for "metal photomasks," an opening of a predetermined shape is pre-formed on a printing screen (a screen made of a metal plate) by etching or laser, and this opening is used as an opening for ink filling, for screen printing.

[0006] In the combination of screen printing plates and metal photomasks, in order to make the support screen bear the elongation caused by the gap during printing, a fabric structure made of a material with high elasticity, i.e. low Young's modulus, is used in the support screen, while a fabric structure made of metal fibers (Patent Document 1) or a metal plate (Patent Document 2) is used as a material with high Young's modulus to reduce the deformation of the image pattern.

[0007] Existing technical documents

[0008] Patent documents

[0009] Patent Document 1: Japanese Patent Application Publication No. 2000-177262

[0010] Patent Document 2: Japanese Patent Application Publication No. 2007-062225 Summary of the Invention

[0011] The problem that the invention aims to solve

[0012] In combined screen printing plates and metal photomasks, the support screen bears the elongation caused by the gaps during printing, therefore its Young's modulus needs to be lower than that of the printing screen. However, when using existing support screens made of nylon fibers, polyester fibers, etc., the Young's modulus of the support screen becomes too low, resulting in weak resistance to the offset of the image forming area caused by the frictional force accompanying the squeegee's sliding during printing, and thus insufficient printing accuracy.

[0013] This invention was made to solve such existing problems, and its purpose is to provide a screen printing plate with excellent printing accuracy.

[0014] means for solving problems

[0015] The main points of this invention are as follows.

[0016] (1) A screen printing plate for screen printing, comprising: a frame; a support screen with its outer periphery fixed to the frame; and a printing screen with its outer periphery fixed to the support screen, wherein the screen printing plate is characterized in that the support screen is made of an n / m twill fabric, wherein n and m are each an integer greater than or equal to 2.

[0017] (2) The screen printing plate according to (1) is characterized in that n and m are each independently an integer less than 5.

[0018] (3) The screen printing plate according to (1) or (2) is characterized in that n and m are the same integer.

[0019] (4) The screen printing plate according to any one of (1) to (3), characterized in that the screen for the support body is the fabric made of synthetic fibers.

[0020] (5) The screen printing plate according to any one of (1) to (4), characterized in that the screen for printing is a fabric made of metal fibers, and the screen printing plate is a composite screen printing plate.

[0021] (6) The screen printing plate according to any one of (1) to (4), characterized in that the screen for printing is made of a metal plate and the screen printing plate is a metal mask.

[0022] Invention Effects

[0023] According to the present invention, a screen printing plate with excellent printing accuracy can be provided. Attached Figure Description

[0024] Figure 1 This is a simplified diagram of a screen printing plate (combined screen printing plate).

[0025] Figure 2 This is an illustration showing how to use a screen printing plate (combined screen printing plate).

[0026] Figure 3 This is a simplified diagram of a screen printing plate (metal mask).

[0027] Figure 4 This is a diagram used to illustrate an opening formed on a glass substrate.

[0028] Figure 5 This is a chart showing the positional offset of the 10th print.

[0029] Figure 6 It is a chart showing the positional offset of the 3000th print.

[0030] Figure 7These are enlarged views of 2 / 1 twill fabric (a) and plain weave fabric (b). Detailed Implementation

[0031] The embodiments of the present invention will now be described in detail.

[0032] First, use Figure 1 The screen printing plate of this embodiment will be described. Figure 1 The screen printing plate 100 shown is a combination screen printing plate in which fabric is used in both the support screen 103 and the printing screen 102.

[0033] The screen printing plate 100 of this embodiment has a frame 101, a support screen 103, and a printing screen 102.

[0034] The outer periphery 103a of the support screen 103 is fixed to the printing plate frame 101. The outer periphery 102a of the printing screen 102 is fixed to the support screen 103. More specifically, the portion where the outer periphery 102a of the printing screen 102 is fixed is the inner periphery 103b of the support screen 103. Here, the outer periphery refers to the area including its outer periphery, and the inner periphery refers to the area including its inner periphery.

[0035] like Figure 1 As shown, the printing screen 102 is positioned at the center of the area surrounded by the screen frame 101, and the support screen 103 is positioned around the printing screen 102 within the area surrounded by the screen frame 101. That is, in the screen printing plate 100 of this embodiment, the printing screen 102, which serves as the inner yarn, is supported on the screen frame 101 by the support screen 103, which serves as the outer yarn.

[0036] The printing frame 101 plays a crucial role in applying tension (e.g., 21 N / cm to 36 N / cm) to and holding the screens 102 and 103, forming a rectangle to allow for the tensioning of the screens 102 and 103. Additionally, the printing frame 101 serves as the mounting part for the printing press and also prevents ink leakage during printing. The printing frame 101 is generally made of square tubing or die-casting from metals such as wood, resin, aluminum, aluminum alloy, steel, and ferroalloys. Aluminum alloys are particularly widely used from the viewpoints of lightweight construction while improving strength, chemical resistance, and processability.

[0037] In this embodiment, the printing plate frame 101 can be made of any material, but to achieve excellent printing accuracy, it is preferable to use metals such as aluminum alloys or iron alloys that have high tensile stability, high strength, and minimal deformation due to changes in temperature and humidity. When using a structure with a metal square tube, it is preferable to increase the wall thickness or to reinforce the structure by adding ribs to the inside of the tube.

[0038] The printing screen 102 is a mesh (fabric) woven from fibers (warp and weft yarns). Specifically, for high-precision printing, i.e., screen printing that forms fine printing patterns, the printing screen 102 is preferably a metal mesh woven with metal fibers having a diameter of 20 μm or less. Furthermore, in this specification, the fine printing patterns include, for example, electrode wiring.

[0039] The density of the fibers in the printing screen 102 is not particularly limited, but from the viewpoint of improving resolution, a mesh size of 400 mesh or higher is preferred. The metal fibers that can be used in the printing screen 102 are preferably stainless steel, tungsten, or other high-strength materials. The fibers (warp and weft) constituting the printing screen 102 are not limited to metal fibers; high-strength synthetic fibers, glass fibers, materials combined or composited with these materials, and materials that can be fiberized can also be used.

[0040] The Young's modulus of the printing screen 102 is not particularly limited, but from the viewpoint of improving printing accuracy, it is preferably 2000 N / mm. 2 That's all. Additionally, in this specification, Young's modulus can be determined from the SS curve (stress-strain curve) obtained through tensile tests using printing screen 102 and support screen 103.

[0041] The function of the support screen 103 in the screen printing plate 100 of this embodiment is to minimize the deformation of the printing screen 102 by bearing the external force applied to the printing screen 102 during printing, thereby achieving high-precision printing.

[0042] The support screen 103 used in the screen printing plate 100 of this embodiment is a fabric composed of warp and weft yarns. From the viewpoint of ensuring the elongation rate for bearing the external force applied to the printing screen 102 during printing, synthetic fibers are preferably used for the warp and weft yarns. There are no particular limitations on the synthetic fibers used; fluorinated fibers, polyethylene terephthalate, polypropylene, 6-nylon, 66-nylon, polyethylene, ethylene-vinyl acetate copolymer, polycarbonate, polyphenylene sulfide (PPS), polyethylene naphthalate, polyetheretherketone, modified polyphenylene ether (PPE), etc., can also be used. In addition, aromatic polyamides, polyarylates, ultra-high molecular weight polyethylene, poly(p-phenylenebenzodioxazole) (PBO), poly(p-phenylenebenzodithiazole) (PBT), poly(p-phenylenebenzodiimidazole) (PBI), carbon fibers, other liquid crystal polymers, two or more materials, such as core-sheath type composite fibers, can also be used. Alternatively, one or more synthetic resin films can be laminated to create a film or sheet-like fabric composite that integrates the fabric and synthetic resin.

[0043] The synthetic fibers that can be used in the support mesh 103 can be monofilaments or multifilaments. In addition, for example, the warp yarns can be multifilaments and the weft yarns can be monofilaments, etc. The cross-sectional shape of the synthetic fibers that can be used in the support mesh 103 can be any shape, such as flat, hollow, porous, triangular, cross-shaped and other irregular cross-sections, in addition to the usual circular cross-section.

[0044] The diameter of the fibers (warp and weft) constituting the support mesh 103 is not particularly limited, and can be set to, for example, 20μm to 100μm. From the viewpoint of bonding with the inner yarn, it is preferably set to 35μm to 70μm. The density of the fibers in the support mesh 103 is not particularly limited, and from the viewpoint of bonding with the inner yarn, it is preferably 100-300 mesh.

[0045] The fabric constituting the support mesh 103 is an n / m twill fabric, where n and m are each an independent integer of 2 or more. Here, n / m twill weave refers to a twill weave in which warp yarns repeatedly pass over n weft yarns and then over m weft yarns (or, weft yarns repeatedly pass over n warp yarns and then over m warp yarns). Furthermore, twill weave is a weaving method characterized by the fact that the portions 103c where warp yarns pass over weft yarns (or weft yarns pass over warp yarns) are staggered by a predetermined distance between adjacent warp yarns longitudinally (or between adjacent weft yarns transversely), thereby forming a linear (ribbon-like) pattern called a twill that is inclined relative to the warp and weft yarns.

[0046] Figure 1 The support structure shown uses a mesh 103 constructed from a 2 / 2 (n=2, m=2) twill fabric. The 2 / 2 twill fabric is as follows: Figure 1 As shown in the enlarged view, the operation of repeatedly passing the warp yarn through two weft yarns and then under two weft yarns is performed (or the operation of repeatedly passing the weft yarn through two warp yarns and then under two warp yarns is performed).

[0047] By constructing the support screen 103 from an n / m (n and m are independently integers of 2 or more) twill fabric, the Young's modulus of the support screen 103 increases compared to the case where it is constructed from a plain weave (n and m are 1) fabric or a 2 / 1 twill fabric. When the Young's modulus of the support screen 103 increases, even when an external force is applied to the printing screen 102 during printing, the support screen 103 is difficult to deform (i.e., the support screen 103 is difficult to stretch). Therefore, according to the screen printing plate 100 of this embodiment, during screen printing, the printing screen is less likely to shift in a direction parallel to the printing surface, making it easier to form a printed pattern at the desired position. Furthermore, it is possible to suppress shape changes in the printed pattern caused by the shift of the printing screen on the printing surface. Furthermore, if the Young's modulus of the support screen 103 increases, the printing screen 102 can easily and quickly separate from the printed surface during printing, and the distance (gap) between the printing screen 102 and the printed surface can be further reduced. Therefore, the screen 100 according to this embodiment can perform high-precision printing.

[0048] In addition, such as Figure 7 As shown in (a), a 2 / 1 twill fabric is a twill fabric (a fabric with n=2, m=1) in which the warp yarns repeatedly pass over two weft yarns and then under one weft yarn (or, repeatedly the weft yarns pass over two warp yarns and then under one warp yarn). For example... Figure 7 As shown in (b), a plain weave is a fabric (a fabric with n=1 and m=1) in which the warp yarns repeatedly pass under one weft yarn.

[0049] The Young's modulus of the support screen 103 is only required to be within the range that can withstand the external force applied to the printing screen 102 during printing (i.e., a range lower than the Young's modulus of the printing screen 102). A higher Young's modulus is preferred, as long as it can withstand the external force applied to the printing screen 102 during printing. Furthermore, from the viewpoint of plate separation, the Young's modulus of the support screen 103 is preferably 800 N / mm. 2 The above. From the viewpoint that the printing screen 102 is unlikely to break relative to the tension applied to the screens 102 and 103, and the external force applied to it during printing, the breaking strength of the support screen 103 is preferably 500 N / 5 cm or higher. A higher breaking strength of the support screen 103 is preferred, but its upper limit can be set, for example, to 1000 N / 5 cm. Furthermore, in this specification, the breaking strength can be obtained based on a tensile test according to JIS L1096.

[0050] The fabric constituting the support mesh 103 can be any twill fabric with an n / m ratio (n and m are independently integers of 2 or more). n and m can be the same integer or different integers, but it is more preferable that n and m are the same integer. When n and m are the same integer, there is no distinction between the front and back sides of the support mesh 103, which improves operability.

[0051] In the fabric constituting the support mesh 103, the larger the values ​​of n and m, the less yarn bending occurs, thus improving the mechanical properties of the support mesh 103, such as Young's modulus and strength. Therefore, larger values ​​of n and m are preferred, but if n and m are too large, it is easy to cause yarn offset, such as warp yarn shifting in the horizontal direction or weft yarn shifting in the vertical direction. Therefore, n and m are preferably integers of 5 or less. In addition, yarn bending refers to the bending of warp yarns passing through weft yarns in the upward and downward directions, and the bending of weft yarns passing through warp yarns in the upward and downward directions.

[0052] From the perspective of further improving printing accuracy, the preferred combinations of n and m are the combination of 2(n) and 2(m) and the combination of 3(n) and 3(m).

[0053] The screen printing plate 100 of this embodiment is used for screen printing to form a printing pattern on a printing surface. The method of using the screen printing plate 100 of this embodiment in screen printing is the same as that of conventionally known screen printing plates, and there are no particular limitations. For example, the following methods can be used.

[0054] First, such as Figure 2 As shown, a photosensitive resin 200 is coated onto the printing screen 102 of the screen printing plate 100. Then, by exposing a designated area of ​​the coated photosensitive resin, the photosensitive resin 200 is cured, and an opening 200a is formed in the photosensitive resin 200. Furthermore, the photosensitive resin 200 can be a negative photosensitive resin in which the exposed area is easily soluble in the developer, or a positive photosensitive resin in which the exposed area is difficult to dissolve in the developer.

[0055] Next, ink I is filled into the opening 200a formed in the photosensitive resin 200, and the ink I is held in the printing screen 102 exposed from the opening 200a. Then, the squeegee S is moved and pressed against the printing screen 102 so that the printing screen 102 holding the ink I is in contact with the printing surface P. As the squeegee S moves, the printing screen 102 pressed against the printing surface P is removed from the printing surface P, thereby transferring the ink I held in the printing screen 102 to the printing surface P. Through these processes, a printed pattern PT can be formed using the screen printing plate 100 of this embodiment.

[0056] Next, the manufacturing method of the screen printing plate 100 of this embodiment will be described.

[0057] The screen printing plate 100 of this embodiment can be manufactured by a manufacturing method including the following steps: a first fixing step in which the outer periphery (the part corresponding to the outer periphery 103a of the support screen 103) is fixed to the frame 101 while a predetermined tension is applied to the n / m (n and m are independently integers of 2 or more) twill fabric (the raw material of the support screen 103); a second fixing step in which the printing screen 102 is overlapped on the twill fabric unfolded on the frame 101 and its outer periphery 102a is fixed to the twill fabric; and a removal step in which a portion of the twill fabric overlapping with the printing screen 102 is removed.

[0058] In the first fixing process, a yarn stretching machine can be used to apply a specified tension to the twill fabric (the raw material of the support mesh 103). Specifically, the four sides of the twill fabric are clamped by the clamps of the yarn stretching machine, and the clamps are pulled mechanically or by air pressure to adjust to a specified tension and a specified deflection angle, thus fixing the outer periphery of the twill fabric (the part corresponding to the outer periphery 103a of the support mesh 103) to the frame 101. Furthermore, the deflection angle refers to the acute angle side of the angle formed by the warp yarn 3a or the weft yarn 3b and the frame 2.

[0059] In the first fixing process, the outer periphery of the twill fabric is fixed to the printing frame 101, or in the second fixing process, the outer periphery 102a of the printing screen 102 is fixed to the twill fabric. For example, an adhesive can be used. As an adhesive, rubber-based, epoxy-based, polyurethane-based, and cyanoacrylate-based adhesives can be cited, but there are no particular limitations in this embodiment. The adhesive can be selected by considering the fiber material used for the screens 102 and 103, the material of the printing frame 101, and the solvent composition of the ink used.

[0060] In the second fixing process, the position where the printing screen 102 overlaps with the twill fabric is not particularly limited as long as it overlaps with the twill fabric. However, from the viewpoint of further improving printing accuracy, it is preferable to place it in the central part of the twill fabric that is tensioned to the printing frame 101.

[0061] In the removal process, a portion of the twill fabric overlapping with the printing screen 102 can be removed, for example, by using a scalpel or a laser. While the removal process removes a portion of the twill fabric overlapping the printing screen 102, it is also possible to leave the entire overlapping area of ​​the twill fabric intact, provided the twill fabric does not overlap with the ink-filled area of ​​the printing screen 102. Furthermore, by removing a portion of the twill fabric in the removal process, the twill fabric becomes the support screen 103.

[0062] The screen printing plate 100 of this embodiment can be manufactured using the above manufacturing method. In this manufacturing method, since a portion of the twill fabric is removed, its tension is reduced. However, if a higher tension is applied beforehand and the twill fabric is tensioned on the plate frame 101, the reduction in printing accuracy caused by the reduced tension can be suppressed.

[0063] Furthermore, the method for manufacturing the screen printing plate 100 in this embodiment is not limited to the method described above. For example, the following method may also be used: before tensioning and setting the screens 102 and 103 on the plate frame 101, a support screen 103 for fixing the outer peripheral portion 102a of the printing screen 102 to the inner peripheral portion 103b is obtained in advance, and the outer peripheral portion 103a is fixed to the plate frame 101 while applying a predetermined tension to the support screen 103.

[0064] According to the screen printing plate 100 of this embodiment, which uses an n / m (n and m are independently integers of 2 or more) twill fabric as the support screen 103, the Young's modulus of the support screen 103 can be increased compared to screen printing plates using plain weave fabric or 2 / 1 twill fabric as the support screen 103. Therefore, a screen printing plate 100 with excellent printing accuracy can be provided.

[0065] In the embodiments described above, a combined screen printing plate (screen printing plate 100) using fabric as the printing screen 102 has been described, but the screen printing plate 100 in this embodiment may also be a metal mask using a metal plate as the printing screen 102.

[0066] Figure 3 This illustrates an example of using a metal plate as a metal mask (screen plate 300) for printing screen 102. Figure 3 In the screen printing plate 300 shown, with Figure 1 The same structure as the screen printing plate 100 shown is labeled with the same symbols and the explanation is omitted.

[0067] like Figure 3 As shown, in the screen printing plate 300, a metal plate is used as the printing screen 302. In addition, the outer periphery 302a of the printing screen 302 is fixed to the inner periphery 103b of the support screen 103, just like the printing screen 102 of the screen printing plate 100.

[0068] The raw material of the metal plate constituting the printing screen 302 is not particularly limited, and metals such as stainless steel, phosphor bronze, nickel, copper, and aluminum can be used. The thickness of the metal plate constituting the printing screen 302 can be appropriately set according to the film thickness of the printed pattern, and is not particularly limited, for example, it can be 20μm to 1000μm.

[0069] An opening 302b, corresponding to the shape of the printed pattern, is formed on the metal plate constituting the printing screen 302. During screen printing, ink is filled into the opening 302b.

[0070] There is no particular limitation on the method for obtaining the metal plate with the opening 302b formed, and existing known methods can be used. Examples of existing known methods include forming the opening on the metal plate by etching, laser processing, and obtaining the metal plate with the opening 302b formed by electroforming.

[0071] Screen printing using screen stencil 300 is performed by filling ink into the openings 302b of the printing screen 302 (metal plate) and transferring the ink held in the openings 302b to the printing surface P. The method of transferring ink to the printing surface P is the same as that used in the case of screen stencil 100, so detailed description is omitted. In screen printing using screen stencil 300, since the openings 302b corresponding to the shape of the printing pattern are pre-formed on the printing screen 302, unlike screen stencil 100, the openings 200a formed by the photosensitive resin 200 can be omitted.

[0072] The manufacturing method of screen printing plate 300 is the same as that of screen printing plate 100, except that a metal plate with openings 302a is used as the screen printing screen 302. Therefore, detailed description is omitted.

[0073] The screen printing plate 300 described above, like the screen printing plate 100, uses an n / m (n and m are independently integers of 2 or more) twill fabric as the fabric constituting the support screen 103. Therefore, according to this embodiment, the support screen 103 of the screen printing plate 300 has a larger Young's modulus compared to screen printing plates using plain weave or 2 / 1 twill fabric. Therefore, a screen printing plate 300 with excellent printing accuracy can be provided.

[0074] Example

[0075] The invention will now be described in more detail by way of examples. However, the invention is not limited to these examples.

[0076] (Example 1)

[0077] As the printing frame, an aluminum frame (outer dimensions: 320mm × 320mm, inner dimensions: 270mm × 270mm, thickness 15mm, wall thickness 2mm, hollow structure) was prepared. As the raw material for the printing screen, a 430-mesh tungsten wire mesh (W40 430-13, manufactured by NBC Meshtec Co., Ltd.) was prepared, in which tungsten metal fibers with a fiber diameter of 13μm are woven into the screen. As the raw material for the support screen, a 2 / 2 twill polyester wire mesh (EX225 HD2 / 2, manufactured by NBC Meshtec Co., Ltd., trade name EX wire mesh) was prepared, in which polyester fibers with a fiber diameter of 55μm are woven into the screen with a 225-mesh screen. Furthermore, the Young's modulus of the tungsten wire mesh used as the raw material for the printing screen, calculated using the slopes of the SS curve at 100N and 200N during tensile testing, is 13110 N / mm. 2 The Young's modulus of the polyester wire mesh used as the support mesh is also 925 N / mm. 2 .

[0078] Adhesive is applied to the outer periphery of the prepared polyester screen (support screen), and the outer periphery of the polyester screen is fixed to the printing frame under a specified tension. After applying adhesive to the outer periphery of the prepared tungsten wire screen (printing screen), the tungsten wire screen is overlapped at the center of the polyester screen stretched to the printing frame, and the outer periphery of the tungsten wire screen coated with adhesive is fixed to the polyester screen. The overlapping area (220mm × 220mm) of the polyester screen and the tungsten wire screen is removed to obtain the screen printing plate of Example 1. In addition, the polyester screen and the tungsten wire screen are fixed at a 23° angle between the warp (or weft) and the printing frame.

[0079] In this embodiment of the screen printing plate, a glass substrate with a thickness of 10 μm is fixed relative to a designated area of ​​a printing screen (tungsten wire mesh), and a silver emulsion containing photosensitive silver halide is coated on its surface. Next, the designated area of ​​the coated silver emulsion is exposed (or laser-etched), thereby forming a cured film of the silver emulsion, and areas where no cured film has formed are etched with a chemical, thereby forming openings in the glass substrate. Figure 4 As shown, on a glass substrate fixed to a printing screen, five openings (a total of 25) are formed at 30mm intervals in both the longitudinal and transverse directions, forming a cross shape when viewed from above (when viewed in the thickness direction). Furthermore, the line width of the cross-shaped openings is 130μm.

[0080] The screen printing plate was configured with the printing screen facing the printing surface, and the printing accuracy was evaluated as described later. Here, the tension in the central part of the printing screen was measured to be 30 N / cm using a tension meter STG-80A (manufactured by Protect Engineering), and the distance (gap) between the printing screen and the printing surface was 1.1 mm.

[0081] (Comparative Example 1)

[0082] As the support screen, EX225 HD2 / 1 (manufactured by NBC Meshtec Co., Ltd.) with a 2 / 1 twill weave of 55μm diameter polyester fibers was used. The screen printing plate of Comparative Example 1 was prepared using the same method as in Example 1, and openings were formed in a predetermined area of ​​the glass substrate to which the printing screen was fixed. Here, the tension at the center of the printing screen was measured to be 30 N / cm using a tension meter STG-80A (manufactured by Protec Engineering Co., Ltd.), and the distance (gap) between the printing screen and the printing surface was 1.1 mm. Furthermore, the Young's modulus of EX225 HD2 / 1, the raw material for the support screen, was 845 N / mm², as shown by the slope of the SS curve at 100 N and 200 N during the tensile test. 2 .

[0083] (printing accuracy)

[0084] Using the screen printing plates of Example 1 and Comparative Example 1, 3000 screen printing cycles were performed. The screen printing was conducted as follows: ink was filled into an opening formed on a glass substrate and held on the printing screen; a squeegee was pressed against the printing screen and moved, thereby transferring the ink held on the printing screen to the printing surface. The printing accuracy was evaluated using the printed patterns from the 10th and 3000th printing cycles using the evaluation method described later.

[0085] (Evaluation Method)

[0086] For each opening formed on the glass substrate, the intersection of the crosshairs is used as a reference point. Each reference point is assigned a number, and coordinates corresponding to the distance from the reference point are set (hereinafter referred to as "reference coordinates"). Specifically, reference point 1 is designated as coordinates (0, 0), and coordinates corresponding to the distance from reference point 1 are set as reference points 1-25. Furthermore, the coordinates used in this evaluation are two-dimensional orthogonal coordinates in the horizontal (X) and vertical (Y) directions, and the coordinates are set using a length measuring machine SQ-9000 (manufactured by Photo Chemical Co., Ltd.).

[0087] For the 10th and 3000th prints, the intersections of the crosshairs forming the printed pattern are used as evaluation points, and each evaluation point is assigned the same number as the corresponding reference point. The coordinates of evaluation point 11 are set to the coordinates (60, 0) of the corresponding reference point 11, and the coordinates corresponding to the distance from evaluation point 11 are set as evaluation points 1-10 and 12-25 (hereinafter, the coordinates of evaluation points 1-25 are referred to as "evaluation coordinates").

[0088] The evaluation coordinates are compared with the reference coordinates, and the positional offset (offset magnitude) of the printed pattern at each point (points 1-25) is calculated based on the differences in the coordinates of each point.

[0089] The evaluation results of the 10th print run are presented below. Figure 5 The evaluation results of the 3000th print run will be presented. Figure 6 Furthermore, in Figure 5 and Figure 6 In the diagram, the vertical axis represents the offset, and the horizontal axis represents the number of each point. Additionally, Figure 5 and Figure 6 In this context, X represents the lateral offset (hereinafter referred to as "offset X"). Figure 5 and Figure 6 In this context, Y represents the vertical offset (hereinafter referred to as "offset Y"). Figure 5 and Figure 6 In this context, a positive offset indicates that the value of the evaluation coordinate increases relative to the value of the reference coordinate, while a negative offset indicates that the value of the evaluation coordinate decreases relative to the value of the reference coordinate.

[0090] Additionally, Table 1 below shows the average offset values ​​in the 10th and 3000th prints. Furthermore, the average offset values ​​were calculated using... Figure 5 and Figure 6 The offsets X and Y shown are obtained according to the following formula (1).

[0091]

[0092] In the above formula (1), A represents the average value of the offset, xn represents the offset X at point n, and yn represents the offset Y at point n.

[0093] (Table 1)

[0094] Average offset (μm) 10th 3000th time Example 1 7.7 7.4 Comparative Example 1 10.1 12.6

[0095] As shown in Table 1, compared with the screen printing plate of Comparative Example 1, the screen printing plate of Example 1 was less prone to positional shift of the printed pattern during the 10th and 3000th screen printing cycles. This result indicates that the screen printing plate of Example 1 possesses excellent printing accuracy.

Claims

1. A screen printing stencil, comprising: Page frame; The support body is made of wire mesh, and its outer periphery is fixed to the frame. And a printing screen, the outer periphery of which is fixed to the support body, wherein the screen is characterized in that... The support body is made of n / m twill fabric. The n and m are each an independent integer greater than 2. The support mesh is a fabric made of synthetic fibers. The printing screen is a fabric made of metal fibers. The screen printing plate is a composite screen printing plate.

2. The screen printing plate according to claim 1, characterized in that, The n and m are each an integer less than 5.

3. The screen printing plate according to claim 1 or 2, characterized in that, n and m are the same integer.

4. A screen printing stencil, comprising: Page frame; The support body is made of wire mesh, and its outer periphery is fixed to the frame. And a printing screen, the outer periphery of which is fixed to the support body, wherein the screen printing plate is characterized in that, The support body is made of n / m twill fabric. The n and m are each an independent integer greater than 2. The support mesh is a fabric made of synthetic fibers. The printing screen is made of a metal plate, and the screen printing plate is a metal mask. During screen printing, the area of ​​the printing screen filled with ink does not overlap with the support screen.

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