Screen printing plate and manufacturing method thereof

Abstract

The present invention addresses the problem of providing a screen printing plate capable of improving printing accuracy and a method for manufacturing the same. According to the technical scheme, the screen printing plate is characterized by comprising a printing plate frame, a printing plate base and a printing plate, and a silk gauze formed using warp yarns and weft yarns woven into a predetermined fabric structure, the silk gauze being stretched on the plate frame in a state in which a predetermined tension is applied, the warp yarns and the weft yarns being stretched by the predetermined tension applied to the silk gauze, the warp yarns and the weft yarns being stretched by the predetermined tension applied to the silk gauze, and the warp yarns and the weft yarns being stretched by the predetermined tension applied to the silk gauze. The thickness of the silk gauze tensioned on the plate frame is reduced to 88% or less of the thickness of the silk gauze to which no tension is applied, the Young's modulus of the silk gauze tensioned on the plate frame is 2000 N / mm2 or more, the diameters of the warp yarns and the weft yarns before knitting are 33 [mu] m or less, the warp yarns and the weft yarns comprise a liquid crystal polymer, and the thickness of the silk gauze on the plate frame is reduced to 88% or less of the thickness of the silk gauze to which no tension is applied. And the predetermined tension is 21 N / cm to 36 N / cm.

Description

[0001] This application is a divisional application of an application with an application date of December 6, 2017, application number 201780075267.9, and invention name “Silk screen plate and its manufacturing method”. Technical Field

[0002] The invention relates to a silk screen plate, in particular to a silk screen plate capable of improving printing accuracy. Background Art

[0003] Screen printing does not require expensive equipment and can be scaled up. It is widely used in the industry as a printing technology that can form a printed coating with a film thickness of about 1μm to several tens of μm in one printing. It is used in various fields such as printing characters on signs and industrial parts, forming electrodes for electronic parts and solar cells represented by printed substrates, dielectric printing for plasma displays, thick film printing, thick mold pattern formation, and hole filling printing.

[0004] The screens used in screen printing include screens made of woven synthetic fibers, screens made of woven metal fibers, screens with multiple holes formed on a metal plate by etching, etc. Among them, synthetic fiber screens are cheap and easy to handle, so they are the most widely used. The material of synthetic fibers is a single filament of a general-purpose fiber such as polyester or nylon, and the wire diameter is generally about 27μm to 60μm. As a metal fiber screen, a screen made of woven stainless steel wire with a diameter of 16μm to 30μm is widely used.

[0005] As mentioned above, screen printing is widely used as a method for forming a printed coating of a thick film of about 1 μm to several tens of μm, but it does not require large vacuum equipment, etc., and has the advantages of being simple and capable of suppressing cost increases. Therefore, screen printing is not only used as a method for forming a thick film, but also attempted to be used as a method for forming a thin film of less than 1 μm. The printed coating of the obtained thin film can be used, for example, for the light-emitting layer of an organic EL element.

[0006] In previous studies, as a method for obtaining a printed coating film of a thin film by screen printing, the following method has been used: a method of obtaining a printed coating film of a thin film by diluting the concentration of solid components contained in ink using a screen plate woven from monofilaments of nylon or polyester, which are general synthetic fibers (Patent Document 1), or a method of obtaining a printed coating film of a thin film by flattening the threads constituting the screen by applying pressure or the like to reduce the thickness of the screen (Patent Document 2).

[0007] Prior art literature

[0008] Patent Literature

[0009] Patent Document 1: Japanese Patent Application Publication No. 2001-155858

[0010] Patent Document 2: Japanese Patent Application Publication No. 2008-74073 Summary of the invention

[0011] Problems to be solved by the invention

[0012] However, in the method of obtaining a thin film printed coating by diluting the concentration of the solid component contained in the ink, as in Patent Document 1, a slight change in the solid component concentration in the ink causes a large change in the film thickness. In addition, since the viscosity of the ink is low due to the low solid component concentration, the edge of the printed coating is prone to bleeding and the edge of the printed coating (i.e., the boundary portion with the printed object) is irregularly protruding, which is a so-called sawtooth phenomenon, and there is a problem that it is difficult to form a fine printed pattern.

[0013] In addition, as in the method disclosed in Patent Document 2, if the wires of the screen are flattened by applying pressure to make the thickness of the screen gauze thinner, the width of the wires constituting the screen gauze (the dimension in the plane perpendicular to the thickness direction of the screen) is larger than the width of the wires before the application of pressure, so that the proportion of the area of ​​the openings in the screen gauze becomes smaller. The openings are the parts filled with ink, which is the raw material for the printed coating, and the ink filled in the openings is transferred to the printed material, thereby obtaining a printed coating. Therefore, if the proportion of the area of ​​the openings becomes smaller, the amount of ink transferred to the printed material decreases, and the ink is difficult to spread evenly on the printed material. Therefore, the method disclosed in Patent Document 2 has the problem of not being able to obtain a printed coating with uniform film thickness.

[0014] The present invention has been made to solve such a problem, and an object of the present invention is to provide a screen plate capable of improving printing accuracy and a method for manufacturing the same.

[0015] Means used to solve problems

[0016] The gist of the present invention is as follows.

[0017] Technical Solution 1. A silk screen plate, characterized in that it comprises: a plate frame; and silk screen yarn, which is formed using warp and weft yarns of synthetic fibers, wherein the silk screen yarn is stretched on the plate frame under a predetermined tension, and the thickness of the silk screen yarn stretched on the plate frame is less than 88% of the thickness of the silk screen yarn to which no tension is applied.

[0018] Technical Solution 2. The screen plate as described in Technical Solution 1 is characterized in that:

[0019] The thickness of the screen gauze stretched on the plate frame is at least 70% of the thickness of the screen gauze without tension applied thereto.

[0020] Technical Solution 3. The screen plate as described in Technical Solution 1 or 2 is characterized in that:

[0021] The synthetic fibers include a liquid crystal polymer.

[0022] Technical Solution 4. The screen plate as described in any one of Technical Solutions 1 to 3, characterized in that:

[0023] The warp threads and the weft threads are monofilaments.

[0024] Technical solution 5. A method for manufacturing a silk screen, characterized by comprising:

[0025] A predetermined tension is applied to a silk screen yarn formed by using warp and weft yarns of synthetic fibers, and the silk screen yarn is stretched on a plate frame.

[0026] The thickness of the screen gauze stretched on the plate frame is set to be 88% or less of the thickness of the screen gauze without tension applied thereto.

[0027] Technical Solution 6. The method for manufacturing a screen plate as described in Technical Solution 5 is characterized in that:

[0028] The predetermined tension is 21 N / cm to 36 N / cm.

[0029] Effects of the Invention

[0030] According to the present invention, it is possible to provide a screen plate capable of improving printing accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 This is a simplified diagram showing a silk screen.

[0032] Figure 2 It is a partial cross-sectional view of the silk screen yarn.

[0033] Figure 3 This is a flowchart illustrating the steps of each process when screen printing is performed.

[0034] Figure 4 This is a cross-sectional view of a screen plate during processing (screen plate preparation) for screen printing.

[0035] Figure 5 It is a cross-sectional view of a screen plate during a process (masking film forming process) when screen printing is performed.

[0036] Fig. 6A It is a cross-sectional view of a screen plate during a process (mask sticking process) when screen printing is performed.

[0037] Figure 6B This is a cross-sectional view of a screen plate during a process (ultraviolet irradiation process) for screen printing.

[0038] Figure 6CIt is a cross-sectional view of a screen plate during a process (opening forming process) when screen printing is performed.

[0039] Figure 7 This is a cross-sectional view of a screen plate during a process (ink filling process) when screen printing is performed.

[0040] Figure 8 This is a cross-sectional view of a screen plate during a process (transfer process) when screen printing is performed. DETAILED DESCRIPTION

[0041] The following describes the embodiments of the present invention. Figure 1 , Figure 2 as well as Figures 4 to 8 In the embodiment, the Z axis and the Y axis are mutually orthogonal axes, and the axis orthogonal to the Z axis and the Y axis is set as the X axis. In the present embodiment, the Z axis direction is set as the thickness direction of the screen plate 1 and the screen gauze 3.

[0042] The screen plate 1 of this embodiment is a printing plate for screen printing. Figure 1 As shown, there is a plate frame 2 and a silk screen yarn 3 stretched on the plate frame 2.

[0043] The plate frame 2 is a rectangular frame and is a member that holds the screen gauze 3. The material of the plate frame 2 is not particularly limited, and for example, metal, casting, resin, or wood can be used.

[0044] The silk screen 3 is a fabric filled with ink and transfers the filled ink to the printed object. Figure 1 As shown, the peripheral edge of the silk screen 3 is fixed to the plate frame 2, and is held on the plate frame 2 while being pulled by the plate frame 2. That is, the silk screen 3 is stretched on the plate frame 2 while a predetermined tension is applied in the X-axis direction and the Y-axis direction. Ink is not limited to a coating for coloring or coloring, and a raw material of an electronic component for the purpose of forming an electronic component such as an electrode or a dielectric may be used, for example, in a liquid or paste state.

[0045] like Figure 1 As shown in the partially enlarged view of , the silk screen 3 has a plurality of warp yarns 3a and a plurality of weft yarns 3b. These warp yarns 3a and weft yarns 3b are woven alternately in the Z-axis direction to form a plain weave fabric composition. In the silk screen plate 1 of this embodiment, the fabric structure of the silk screen 3 is not particularly limited, and it can also be a twill weave or a satin weave. However, from the viewpoint of making the thickness of the silk screen 3 in the Z-axis direction thinner and less likely to produce net knots, the fabric structure of the silk screen 3 is preferably a plain weave.

[0046] A plurality of warp threads 3a are arranged in parallel at a predetermined interval w1 on the XY plane. A plurality of weft threads 3b are arranged perpendicularly to the warp threads 3a on the XY plane and are arranged in parallel at a predetermined interval w2. An opening 3c is formed in the space surrounded by the warp threads 3a and the weft threads 3b and is filled with ink described later. In the screen plate 1 of the present embodiment, the interval w1 and the interval w2 are the same. However, the interval w1 and the interval w2 may also be different.

[0047] Figure 2 yes Figure 1 AA cross-sectional view of the silk screen yarn 3 shown. Figure 2 As shown, the cross section of the warp 3a is an elliptical shape having a long diameter d11 in the X-axis direction and a short diameter d12 in the Z-axis direction. Similarly, the cross section of the weft 3b is an elliptical shape having a long diameter d21 in the Y-axis direction (see Figure 1 ) and an elliptical shape of a short diameter d22 in the Z-axis direction. In the screen plate 1 of the present embodiment, the long diameter d11 (hereinafter also referred to as "width d11") of the warp 3a is the same as the long diameter d21 (hereinafter also referred to as "width d21") of the weft 3b, and the short diameter d12 (hereinafter also referred to as "thickness d12") of the warp 3a is the same as the short diameter d22 (hereinafter also referred to as "thickness d22") of the weft 3b. From the viewpoint of making it easy to weave the silk screen yarn 3 and being able to suppress the deviation in the strength (e.g., tensile strength) of the warp 3a and the weft 3b in the silk screen yarn 3, the cross-sectional shape of the warp 3a and the weft 3b before weaving is preferably a circle with the same diameter. In addition, the widths d11 and d21 of the warp 3a and the weft 3b may be different from each other, and the thicknesses d12 and d22 of the warp 3a and the weft 3b may be different from each other.

[0048] The screen yarn 3 has an intersection where the warp yarn 3a and the weft yarn 3b overlap in the Z-axis direction and a non-intersection where the warp yarn 3a and the weft yarn 3b do not overlap in the Z-axis direction. The thickness t of the screen yarn 3 is the thickness of the intersection where the warp yarn 3a and the weft yarn 3b overlap, and is the sum of the thickness d12 of the warp yarn 3a and the thickness d22 of the weft yarn 3b. In order to form a printed coating film with a film thickness of less than 1 μm, it is effective to reduce the thickness t of the screen yarn 3. In order to reduce the thickness t of the screen yarn 3, it is effective to use warp yarns 3a and weft yarns 3b with smaller thicknesses.

[0049] The warp yarn 3a and the weft yarn 3b are made of synthetic fibers, and are stretched by applying tension in the length direction, so that the thickness d12 and d22 are reduced. In the screen yarn 3 stretched on the plate frame 2, since tension is applied to the warp yarn 3a and the weft yarn 3b in the length direction, the warp yarn 3a and the weft yarn 3b are in a stretched state. Moreover, the total thickness (d12+d22) of the warp yarn 3a and the weft yarn 3b is reduced to less than 88% of the total thickness of the warp yarn 3a and the weft yarn 3b to which tension is not applied in the length direction. That is, the thickness t of the screen yarn 3 stretched on the plate frame 2 is reduced to less than 88% of the thickness of the screen yarn 3 to which tension is not applied. Preferably, the thickness t of the screen yarn 3 is greater than 70% and less than 88% of the thickness of the screen yarn 3 to which tension is not applied, and more preferably, the thickness t of the screen yarn 3 is greater than 75% and less than 86% of the thickness of the screen yarn 3 to which tension is not applied. In addition, the length direction of the warp 3a is the Y-axis direction, and the length direction of the weft 3b is the X-axis direction. The elongation of the warp 3a and the weft 3b can be plastic deformation or elastic deformation, but preferably elastic deformation. In the case where the elongation of the warp 3a and the weft 3b is elastic deformation, even if the warp 3a and the weft 3b are deformed (elongated) by repeated screen printing, the warp 3a and the weft 3b are also easy to return to the state before the screen printing. Therefore, even if the screen printing is repeated, it is easy to maintain a state of improving printing accuracy. On the other hand, in the case where the elongation of the warp 3a and the weft 3b is plastic deformation, when the warp 3a and the weft 3b are deformed (elongated) by repeated screen printing, it is easy to maintain a deformed (elongated) state. Therefore, in the case where the screen printing is repeated, it is difficult to maintain a state of improving printing accuracy. In addition, the so-called elastic deformation refers to the deformation in which the warp yarn 3a and the weft yarn 3b are stretched by external force and then return to their original length when the external force is removed, and the so-called plastic deformation refers to the deformation in which the warp yarn 3a and the weft yarn 3b are stretched by external force and remain in the stretched state even after the external force is removed.

[0050] Here, the warp 3a and weft 3b composed of synthetic fibers are easily flattened in the direction orthogonal to the Z axis (X axis and Y axis direction) by weaving into a predetermined fabric composition, even if the cross-sectional shape before weaving is a perfect circle. If the flat warp 3a and weft 3b (silk mesh 3) woven into a predetermined fabric composition are stretched on the plate frame 2, the flat warp 3a and weft 3b are further flattened in the direction orthogonal to the Z axis while stretching in the length direction. Therefore, the total thickness of the warp 3a and weft 3b is reduced to a thickness of less than 88%, and the thickness t of the silk mesh 3 stretched on the plate frame 2 becomes less than 88% of the thickness of the silk mesh 3 without tension. In this way, the screen plate 1 of the present embodiment is easy to become thinner because the thickness t of the screen gauze 3 stretched on the plate frame 2 is reduced to less than 88% of the thickness of the screen gauze 3 without tension, so it is easy to form a printed coating with a thin film thickness (for example, a printed coating with a film thickness of less than 1 μm). When the thickness t of the screen gauze 3 stretched on the plate frame 2 is greater than 88% of the thickness of the screen gauze 3 without tension, the tension applied to the screen gauze 3 becomes smaller. Specifically, when using a silk containing a liquid crystal polymer and other easily elongated silk, if the thickness t of the screen gauze 3 is made greater than 88% of the thickness of the screen gauze 3 without tension, the tension applied to the screen gauze 3 becomes smaller. Therefore, it is necessary to increase the setting amount of the gap (the distance between the screen gauze 3 and the printed object) required for the separation of the printing plate. If the setting amount of the gap becomes larger, the deformation of the screen gauze 3 becomes larger during screen printing, so it is difficult to form the shape of the desired printed pattern. In addition, if the gap setting amount becomes larger, it may be difficult to form a printed pattern at a predetermined position on the printed object, or the printing position may be easily offset during repeated printing. From the viewpoint of reducing the gap setting amount required for separating the printing plates, the Young's modulus of the silk screen 3 stretched on the plate frame 2 is preferably 2000 N / mm 2 On the basis of making the thickness t of the screen yarn 3 stretched on the plate frame 2 less than 88% of the thickness of the screen yarn 3 without tension applied, by making the Young's modulus of the screen yarn 3 stretched on the plate frame 2 2000N / mm 2 The above can reduce the setting amount of the gap required for plate separation, thereby further improving the printing accuracy. In addition, when the Young's modulus of the silk screen 3 stretched on the plate frame 2 is high, it is necessary to use a wire with a high Young's modulus. However, in the case of such a wire, when making the plate or stretching the yarn, the handling property may be poor due to the slight unevenness of the overall tension balance of the silk screen 3, such as mesh damage. Therefore, it is preferably set to 30000N / mm 2Below. In addition, the Young's modulus of the silk screen yarn 3 stretched on the plate frame 2 refers to the average value of the Young's modulus of the silk screen yarn 3 stretched on the plate frame 2 in the longitudinal direction (Y direction) and the transverse direction (X direction), which can be obtained as follows: in a state where the tension applied by being stretched on the plate frame 2 is applied to the silk screen yarn 3, the silk screen yarn 3 is stretched in the longitudinal direction (Y direction) and the transverse direction (X direction) respectively, and the Young's modulus calculated from the tangent of the rising part of the obtained load-elongation curve is obtained by adding and averaging each Young's modulus.

[0051] In addition, it is preferred that the thickness t of the silk screen 3 stretched on the plate frame 2 is 70% or more of the thickness of the silk screen 3 without tension. When the thickness t of the silk screen 3 stretched on the plate frame 2 is less than 70% of the thickness of the silk screen 3 without tension, the silk screen 3 is cut at the moment of tension application due to high tension before being stretched on the plate frame 2, or the warp yarn 3a and the weft yarn 3b of the silk screen 3 stretched on the plate frame 2 become thinner and become easy to cut, so that the printing durability is sometimes poor.

[0052] In addition, in the method of laying the screen yarn 3 on the plate frame 2 to flatten the warp 3a and the weft 3b by applying pressure, as in the prior art, when flattened, the warp 3a and the weft 3b are hardly stretched in the length direction, so the warp 3a and the weft 3b are easy to expand in the width direction. On the other hand, in the screen plate 1 of the present embodiment, as described above, when the warp 3a and the weft 3b are flattened, the warp 3a and the weft 3b are stretched in the length direction. Since the cross-sectional area of ​​the warp 3a and the weft 3b stretched in the length direction is smaller than the cross-sectional area of ​​the warp 3a and the weft 3b that are not stretched, even if the warp 3a and the weft 3b are flattened, the expansion of the warp 3a and the weft 3b in the width direction can be suppressed. That is, when the warp 3a and the weft 3b are flattened, the expansion of the warp 3a and the weft 3b in the width direction can be suppressed by stretching the warp 3a and the weft 3b in the length direction. Therefore, compared with the existing screen plate 1 in which the thickness of the screen yarn 3 is adjusted to the same thickness t as the screen yarn 3 involved in the present embodiment by applying pressure, etc., the widths d11 and d21 of the warp yarn 3a and the weft yarn 3b are difficult to expand, and the opening 3c (the opening ratio described later is difficult to reduce) is easy to maintain. If the opening 3c is maintained, it is easy to fill more ink into the opening 3c, thereby making it easier to transfer more ink to the printed object. That is, according to the screen plate 1 of the present embodiment, since the ink is easy to spread evenly on the printed object, it is easy to form a printed coating with uniform film thickness, thereby improving printing accuracy. In addition, the width direction of the warp yarn 3a is the X-axis direction, and the width direction of the weft yarn 3b is the Y-axis direction.

[0053] In the present embodiment, an example of flattening the warp 3a and the weft 3b by weaving is described, but the warp 3a and the weft 3b may be flattened without weaving (that is, the cross-sectional shape of the warp 3a and the weft 3b may also be a perfect circle). In the case where the cross-sectional shape of the woven warp 3a and the weft 3b is a perfect circle, by stretching the silk screen yarn 3 on the plate frame 2 with a predetermined tension, the warp 3a and the weft 3b are stretched in the length direction while the cross-sectional shape of the warp 3a and the weft 3b remains a perfect circle. In addition, the total thickness (diameter) of the warp 3a and the weft 3b is reduced to a thickness of less than 88%, and the thickness t of the silk screen yarn 3 stretched on the plate frame 2 becomes less than 88% of the thickness of the silk screen yarn 3 to which no tension is applied. That is, even when the cross-sectional shape of the woven warp yarn 3a and weft yarn 3b is a perfect circle, the screen plate 1 of this embodiment can easily make the thickness t of the screen yarn 3 thinner, and can easily form a printed coating with a thin film thickness (for example, a printed coating of a thin film of less than 1 μm). In addition, by stretching the screen yarn 3 on the plate frame 2 with a predetermined tension, when the diameter of the warp yarn 3a and weft yarn 3b is reduced, the width d11 and d21 of the warp yarn 3a and weft yarn 3b are also reduced, so that the opening rate can be increased compared with the existing screen plate 1 in which the thickness of the screen yarn 3 is adjusted to the same thickness t of the screen yarn 3 involved in this embodiment by applying pressure, etc. Therefore, even when the cross-sectional shape of the woven warp yarn 3a and weft yarn 3b is a perfect circle, the screen plate 1 of this embodiment can fill more ink into the opening 3c, thereby improving the printing accuracy.

[0054] The synthetic fibers constituting the warp 3a and the weft 3b may be the same synthetic fibers or different synthetic fibers. From the viewpoint of facilitating weaving the mesh yarn 3 and suppressing the strength deviation of the warp 3a and the weft 3b in the mesh yarn 3, it is preferred that the synthetic fibers constituting the warp 3a and the weft 3b are the same synthetic fibers.

[0055] The synthetic fiber constituting the warp 3a and the weft 3b may be a monofilament or a multifilament, the warp 3a may be a multifilament, the weft 3b may be a monofilament, or a combination thereof inversely. From the viewpoint of improving printing accuracy (such as the sharpness and resolution of the printed material) and the durability of the printed coating, it is preferred that both the warp 3a and the weft 3b are monofilaments. In particular, in the case of printing a printed coating of a thin film below 1 μm, a monofilament is preferred. When a multifilament is used, the diameter (short diameter d12 and long diameter d11) of the warp 3a and the diameter (short diameter d22 and long diameter d21) of the weft 3b tend to become larger, making it difficult to print a printed coating of a thin film. Monofilament synthetic fibers may be composed of a single material or of two or more materials with different properties. The synthetic fiber composed of two or more materials may be a core-sheath type fiber in which the material of the core part of the cross section is different from that of the sheath part, a mixed fiber obtained by mixing two or more molten materials, a core-sheath type fiber in which the raw materials of the core part and the sheath part are obtained by mixing two or more molten raw materials, and a sea-island type fiber in which the raw materials of the multiple island parts extending in the length direction of the fiber and the sea parts surrounding the island parts are different. In addition, it can also be a core-sheath type composite fiber in which the island parts and the sea parts are formed in the sheath part and the core part. In addition, the surface of the synthetic fiber can also be coated or modified with an organic substance or an inorganic substance.

[0056] The fabric density of the silk screen 3 is defined by the number of threads (warp 3a, weft 3b) in one inch of the silk screen 3 (hereinafter also referred to as "mesh number"). In the silk screen plate 1 of the present embodiment, the mesh number of the warp 3a and the mesh number of the weft 3b may be the same or different. From the viewpoint of suppressing the strength deviation of the warp 3a and the weft 3b in the silk screen 3, it is preferred that the mesh number of the warp 3a and the mesh number of the weft 3b are the same.

[0057] If the diameters (short diameter and long diameter) of the wires (warp 3a, weft 3b) used in the silk screen 3 are the same, then when the number of meshes is increased, the strength (for example, breaking strength or tear strength) of the silk screen 3 becomes higher, but the opening rate described later becomes lower, which easily reduces the printing accuracy (for example, it is difficult to print pattern lines arranged at a high density, etc.). On the other hand, when the number of meshes is reduced, the opening rate becomes higher, but the strength of the silk screen 3 tends to become lower. Therefore, there is a preferred range for the number of meshes of the silk screen 3. The preferred range of the number of meshes depends on the material, strength, diameter, etc. of the wire, and therefore cannot be uniquely determined. From the perspective of having sufficient strength to suppress line breaks in the process of stretching the silk screen 3 on the plate frame 2 or in the printing process, the number of meshes of the warp 3a and the weft 3b are preferably 180 meshes or more, particularly preferably 220 meshes or more, and further preferably 300 meshes or more. In addition, from the viewpoint of improving printing accuracy, the mesh counts of the warp yarn 3 a and the weft yarn 3 b are preferably 420 meshes or less and 350 meshes or less, respectively, and particularly preferably 330 meshes or less.

[0058] In addition, the so-called opening ratio (%) is the ratio of the area of ​​the opening portion 3c per predetermined area of ​​the screen yarn 3 in the XY plane, and can be calculated using the following formula (1). In addition, in the following formula (1), w1 represents the interval between adjacent warp yarns 3a, w2 represents the interval between adjacent weft yarns 3b, d11 represents the width of the warp yarn 3a, and d21 represents the width of the weft yarn 3b.

[0059] Opening ratio (%) = (w1×w2) / {(w1+d11)×(w2+d21)}×100(1)

[0060] In order to manufacture a thinner mesh yarn 3 with a thickness t by weaving, the tensile strength of the warp yarn 3a and the weft yarn 3b before weaving is preferably 10 cN / dtex or more according to the test method of JIS L1013. When the tensile strength of any one of the warp yarn 3a and the weft yarn 3b is less than this value, the yarn is likely to break frequently during weaving due to insufficient strength, and weaving becomes difficult, making it difficult to obtain a thinner mesh yarn 3 with a thickness t.

[0061] The tear strength of the screen gauze 3 can be set to 200 gf or more, preferably 300 gf or more, and more preferably 400 gf or more. When the tear strength is less than 200 gf, the screen gauze 3 may break depending on the method of stretching the screen gauze 3 on the plate frame 2, and it is sometimes difficult to obtain the screen plate 1 in which the screen gauze 3 is stretched with sufficient tension to appropriately separate the plate as described later. In addition, the tear strength can be measured according to JIS L1096.

[0062] The warp 3a and weft 3b before weaving can be synthetic fibers with a perfect circular cross-sectional shape or elliptical synthetic fibers. In the case where the warp 3a and weft 3b before weaving are synthetic fibers with a perfect circular cross-sectional shape, in order to improve printing accuracy or to facilitate the formation of a printed coating of a thin film, the diameter of the warp 3a and the diameter of the weft 3b before weaving are preferably 45 μm or less, more preferably 40 μm or less, particularly preferably 35 μm or less, and even more particularly preferably 33 μm or less. If the diameter of the warp 3a and the diameter of the weft 3b are 35 μm or less, particularly 33 μm or less, it is easy and reliable to print a printed coating of a thin film arranged with a width of 150 μm, particularly 60 μm.

[0063] The synthetic fibers constituting the warp 3a and the weft 3b are not particularly limited as long as they can be stretched in the length direction when the screen yarn 3 is stretched on the frame 2, and the thickness t of the screen yarn 3 is less than 88% of the thickness of the screen yarn 3 without tension. For example, it is preferred to use synthetic fibers formed by polyesters such as polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polyethylene naphthalate (PEN), liquid crystal polyester, nylon, polyphenylsulfone (PPS), polyetheretherketone (PEEK), and synthetic fibers formed by combining two or more of them. Among these substances, synthetic fibers formed by nylon and polyester are preferably used. In addition, synthetic fibers containing liquid crystal polymers such as liquid crystal polyester are elastic and have excellent dimensional stability. Therefore, when using synthetic fibers containing liquid crystal polymers as warp 3a and weft 3b, even if screen printing is repeated, warp 3a and weft 3b are difficult to deform. Therefore, synthetic fibers containing liquid crystal polymers are suitable for repeated printing of precise printed patterns, and are therefore particularly preferred. In addition, a liquid crystal polymer refers to a polymer that exhibits liquid crystallinity in a molten state or a solution state.

[0064] As described above, in order to form a printed coating film of a thin film less than 1 μm, it is effective to thin the thickness t of the silk screen gauze 3. In the case of forming a printed coating film of a thin film less than 1 μm, the thickness t of the silk screen gauze 3 is preferably 30 μm or less. In order to form a printed coating film of a thin film less than 0.5 μm, the thickness t of the silk screen gauze 3 is preferably 25 μm or less. In order to form a printed coating film of a thin film less than 0.3 μm, the thickness t of the silk screen gauze 3 is preferably 20 μm or less. In addition, the lower limit value of the thickness t of the silk screen gauze 3 is not particularly limited, but can be 12 μm or more.

[0065] In order to make the film thickness of the printed coating uniform and improve the identity (reproducibility) of the repeatedly formed printed coating, the opening rate (%) of the silk screen 3 is preferably within a certain range, preferably greater than 20% and less than 60%. If the opening rate is less than 20%, the amount of ink filled per unit area of ​​the silk screen 3 decreases, and the amount of ink transferred to the printed object tends to decrease. Therefore, it is difficult for the ink to spread evenly on the printed object, and it is difficult to form a printed coating with uniform film thickness. If the opening rate exceeds 60%, the end of the printed coating (that is, the boundary portion with the printed object) is difficult to become smooth, and irregularly protruding serrations are likely to occur at the end of the printed coating. In addition, if the opening rate exceeds 60%, the silk screen 3 is easily deformed during the printing process, and the masking film formed on the silk screen 3 described later is likely to rupture. Furthermore, in order to achieve a high opening ratio exceeding 60%, it is necessary to reduce the widths d11 and d21 of the warp yarns 3a and the weft yarns 3b, or to reduce the number of meshes, etc. As a result, the strength of the mesh yarn 3 is likely to decrease.

[0066] Next, use Figure 3 to Figure 8 An example of a method of performing screen printing using the screen plate 1 of the present embodiment will be described. Figure 3 1 is a flowchart showing the steps of each process when screen printing is performed using the screen plate 1 of the present embodiment. Figures 4 to 8 It is a cross-sectional view of the screen plate 1 in each process.

[0067] In the process of step S100, if Figure 4 As shown, a screen plate 1 is prepared in which a screen gauze 3 is stretched on a plate frame 2 with a predetermined tension applied thereto. In the screen plate 1, a thickness t of the screen gauze 3 is 88% or less of a thickness of the screen gauze 3 without tension applied thereto.

[0068] In the process of step S101, Figure 5 As shown, a shielding film 10 is formed on the surface (upper surface and lower surface) of the silk screen 3. As the shielding film 10, for example, a photosensitive resin (photoresist) that is cured by irradiation with light can be used. As the photosensitive resin, diazo resins, free radical resins, stilbene resins, etc. can be used, and the photosensitive resins that can be used are not limited by the curing mechanism. In addition, as long as the photosensitive resin can form the shielding film 10, there is no limitation on the form of the shielding film 10 before it is formed. For example, it can be used in the form of a liquid or a solid (film). In the case of using a liquid photosensitive resin, for example, the shielding film 10 can be formed by applying a liquid photosensitive resin containing a solvent on the silk screen 3 and drying it to evaporate and remove the solvent. The thickness of the shielding film 10 in the Z-axis direction can be adjusted by repeatedly applying and drying. In addition, in the silk screen 3, the shielding film 10 is arranged on both the upper surface contacted by the scraper 13 described later and the lower surface contacted by the printed object 14 described later, but it can also be arranged only on the lower surface. From the viewpoint of improving the adhesion of the masking film 10 to the screen gauze 3 and improving the durability of the masking film 10, it is preferably provided on both the upper surface and the lower surface.

[0069] In the process of step S102, if Figure 6A to Figure 6C As shown in FIG. 1 , in the masking film 10 formed on the surface of the screen gauze 3, an opening 10a is formed at a position corresponding to the desired printing pattern. Specifically, first, as Fig. 6A As shown in FIG. 1 , a mask 11 having a shape corresponding to the desired printing pattern is attached to the upper surface of the shielding film 10. As the mask 11, a film or glass can be used. Figure 6B As shown in FIG. 1 , the shielding film 10 to which the mask 11 is attached is irradiated with ultraviolet rays from above the silk screen 1. Then, the shielding film 10 irradiated with ultraviolet rays is developed, as shown in FIG. Figure 6CAs shown, the mask 11 and the area of ​​the shielding film 10 covered by the mask 11 are removed. Through these processes, the openings 10a are formed in the shielding film 10 at positions corresponding to the desired printing pattern.

[0070] In addition, in the process of step S102, although the area of ​​the shielding film 10 covered by the mask 11 is removed to form the opening 10a, the type of the shielding film 10 or the type of the developer may be changed, so that the area of ​​the shielding film 10 covered by the mask 11 is left and the area of ​​the shielding film 10 not covered by the mask 11 is removed to form the opening 10a. In addition, in the process of step S102, although the mask 11 is attached to the upper surface of the shielding film 10, the mask 11 may be attached to the lower surface of the shielding film 10. In the case where the mask 11 is attached to the lower surface of the shielding film 10, the shielding film 10 to which the mask 11 is attached can be irradiated with ultraviolet rays from below the screen 1.

[0071] In the process of step S103, Figure 7 As shown, the ink 12 on the masking film 10 is moved by a squeegee 11, and the screen 3 (opening 3c) is filled with the ink 12 through the opening 10a. By this process, the screen 3 is filled with the ink 12 only at the position corresponding to the desired printing pattern.

[0072] In the process of step S104, Figure 8 As shown, the scraper 13 is moved while being pressed against the silk screen 3 so that the silk screen 3 filled with ink 12 contacts the printed object 14. Through this process, the ink 12 filled in the silk screen 3 is transferred to the printed object 14. The transfer of the ink 12 to the printed object 14 is performed by separating the silk screen 3 pressed against the printed object 14 from the printed object 14, that is, the so-called plate separation occurs.

[0073] The ink 12 transferred by the process of step S104 is used to print a desired printed pattern 12' on the printed object 14. The printed pattern 12' refers to a pattern (including figures, characters, lines, etc.) formed by a printed coating film.

[0074] Here, from the viewpoint of easy formation of a thin-film printed coating, the thickness of the shielding film 10 in the Z-axis direction is preferably thin, but it can be determined in consideration of the ability to stably form the shielding film 10, the durability of the shielding film 10, the sealing property of controlling the spread of the ink 12 filled in the opening 3c of the screen gauze 3, etc. Since the strength of the thin shielding film 10 is low, when the shielding film 10 is removed by spraying water or blowing air when the opening 10a is formed, the area of ​​the shielding film 10 not covered by the mask 11 may also be removed. In addition, in order to suppress the bleeding of the printed pattern 12', the thickness of the shielding film 10 is preferably thick.

[0075] From this point of view, the thickness of the shielding film 10 is preferably 1 μm or more and 10 μm or less, more preferably 2 μm or more and 7 μm or less, and further preferably 3 μm or more and 5 μm or less. Here, the thickness of the shielding film 10 is the thickness of the amount added to the thickness t of the screen gauze 3, and refers to the value obtained by subtracting the thickness t of the screen gauze 3 from the thickness of the screen gauze 3 including the shielding film 10. In addition, the thickness of the shielding film 10 formed on the upper surface of the screen gauze 3 can be, for example, 0 to 2 μm.

[0076] In addition, in order to prevent the substance constituting the masking film 10 (for example, photosensitive resin) from eluting into the organic solvent that may be contained in the ink 12, thereby suppressing the bleeding of the printed pattern 12' and improving the printing accuracy, the masking film 10 may contain a water-repellent and oil-repellent component as a part of the material constituting the masking film 10. Such a masking film 10 may be a single-layer masking film 10 containing a water-repellent and oil-repellent component, or a masking film 10 in which a layer containing a water-repellent and oil-repellent component and a layer not containing a water-repellent and oil-repellent component are stacked. In addition, a masking film 10 in which a water-repellent and oil-repellent component (polymer, etc.) is coated on the surface of a layer not containing a water-repellent and oil-repellent component may be used. In order to improve printing accuracy, the waterproof and oil-proof components can be coated only on the surface of the masking film 10 arranged on the lower surface of the silk screen 3. However, in order to inhibit the substance constituting the masking film 10 (such as resin) from being eluted into the organic solvent that may be contained in the ink 12, it is preferably coated on the surface of the masking film 10 on both the lower surface and the upper surface of the silk screen 3.

[0077] As the components having water-repellency and oil-repellency, substances containing fluorine and silicon can be cited. For example, fluorine- or silicon-containing resins, oligomers, oils, monomers, etc. can be mixed into the raw material (photosensitive resin) of the shielding film 10, or coated on the surface of the shielding film 10 to impart water-repellency and oil-repellency.

[0078] Furthermore, when the ink 12 contains an organic solvent, in order to suppress the dissolution of the substance (e.g., resin) constituting the shielding film 10 in the organic solvent or the expansion of the shielding film 10, after the shielding film 10 is treated with a liquid or the printed pattern 12' is formed, the shielding film 10 may be additionally irradiated with ultraviolet light to increase the crosslinking density of the shielding film 10. By performing these treatments, the stability and durability of the shielding film 10 during printing can be improved.

[0079] Next, a method for manufacturing the screen plate 1 according to the present embodiment will be described.

[0080] The screen plate 1 of this embodiment can be manufactured by weaving warp yarns 3a and weft yarns 3b to form screen yarn 3, and the obtained screen yarn 3 is stretched on the plate frame 2 under a predetermined tension, so that the thickness of the screen yarn stretched on the plate frame 2 is less than 88% of the thickness of the screen yarn without tension. As the warp yarns 3a and weft yarns 3b used in weaving, synthetic fibers with a perfect circular cross-sectional shape can be used, which can be easily flattened in a direction orthogonal to the Z axis by weaving.

[0081] In order to stretch the silk screen 3 on the plate frame 2, a tensioning machine can be used. Specifically, the parts of the silk screen 3 in the four directions are clamped by the clamps of the tensioning machine, and the clamps are tightened by mechanical or air pressure to adjust to a predetermined tension and a predetermined deflection angle, and the silk screen 3 is fixed on the plate frame 2 under a predetermined tension. Then, the silk screen 3 is cut along the periphery of the plate frame 2. For the predetermined tension applied to the silk screen 3, considering the elongation characteristics of the warp 3a and the weft 3b, as long as the thickness t of the silk screen 3 stretched on the plate frame 2 is less than 88% of the thickness of the silk screen 3 without tension (the silk screen 3 before being stretched on the plate frame 2). For example, the predetermined tension applied to the silk screen 3 can be in the range of 21N / cm to 36N / cm. In the case of requiring high printing accuracy, the tension is more preferably in the range of 25N / cm to 36N / cm. The off-angle refers to the angle on the acute side of the angle formed by the warp yarn 3 a or the weft yarn 3 b and the plate frame 2 .

[0082] As a method of fixing the silk screen 3 on the plate frame 2, an adhesive can be used. As the adhesive, rubber, epoxy, polyurethane, and cyanoacrylate adhesives can be cited, but there is no particular limitation in this embodiment, and the selection can be made by considering the material of the silk screen 3 and the material of the plate frame 2, the solvent contained in the ink used, etc.

[0083] The predetermined tension applied to the screen gauze 3 is an important factor in the above-mentioned plate separation. If the tension is small, the plate separation cannot be properly performed, the transfer of the ink becomes uneven, the film thickness of the printed coating is biased, and the printing accuracy is easily reduced. As the tension for properly performing the plate separation, since each unit width of the screen gauze 3 needs to be 21N / cm or more, in order to prevent the wire from being broken or the screen gauze 3 from being broken in the process of placing the screen gauze 3 on the plate frame 2 or in each process of printing, the breaking strength of the screen gauze 3 is preferably 40N / cm or more. In addition, the breaking strength can be measured according to JIS L1096.

[0084] As described above, in the screen plate 1 of the present embodiment, the thickness t of the screen yarn 3 stretched on the plate frame 2 is less than 88% of the thickness of the screen yarn 3 to which tension is not applied (the screen yarn 3 before being stretched on the plate frame 2). That is, the screen yarn 3 is stretched on the plate frame 2 and a predetermined tension is applied, thereby the warp yarn 3a and the weft yarn 3b are stretched, and the total thickness of these yarns (d12+d22) is reduced to less than 88% of the total thickness of the warp yarn 3a and the weft yarn 3b to which tension is not applied. In the screen plate 1 of the present embodiment having such a structure, the thickness t of the screen yarn 3 is easy to be thinned, and a printed coating with a thin film thickness (for example, a printed coating of a thin film of less than 1 μm) is easy to form.

[0085] In addition, when the screen yarn 3 is stretched on the plate frame 2 with a predetermined tension, the thicknesses d12 and d22 of the warp yarn 3a and the weft yarn 3b are reduced while the thicknesses d12 and d22 are extended in the length direction, so that the expansion of the warp yarn 3a and the weft yarn 3b in the width direction is suppressed. Therefore, compared with the screen plate 1 in which the thickness of the screen yarn 3 is adjusted to the same thickness t of the screen yarn 3 involved in the present embodiment by flattening the warp yarn 3a and the weft yarn 3b by applying pressure, the opening ratio is difficult to decrease, and more ink 12 can be filled into the opening 3c. That is, according to the screen plate 1 of the present embodiment, it is easy to form a printing coating with a uniform film thickness, which can improve printing accuracy.

[0086] In addition, as described above, the screen plate 1 of the present embodiment can suppress the expansion of the warp yarn 3a and the weft yarn 3b in the width direction, so even if the number of meshes of the warp yarn 3a and the weft yarn 3b is increased, it is easy to maintain the opening rate, and it is possible to suppress the reduction of printing accuracy. That is, according to the screen plate 1 of the present embodiment, it is possible to simultaneously achieve the improvement of the strength (e.g., breaking strength, tearing strength) of the screen yarn 3 and the improvement of printing accuracy.

[0087] Furthermore, the screen plate 1 of the present embodiment can form a thin film of 1 μm or less by adjusting the thickness t of the screen yarn 3. Therefore, even without diluting the solid content concentration of the ink, a thin film of printed coating can be formed, and the reduction in printing accuracy caused by diluting the solid content concentration and the change in the film thickness of the printed coating caused by the change in the solid content concentration can be suppressed.

[0088] In addition, the screen plate 1 of the present embodiment is easy to reduce the thickness d12 and d22 of the warp yarn 3a and the weft yarn 3b compared to the screen plate 1 in which the thickness of the screen yarn 3 is changed by more than 88% by applying a predetermined tension. Therefore, when the thickness t of the screen yarn 3 in these screen plates 1 is made the same, the screen plate 1 of the present embodiment can use thicker yarns as the warp yarn 3a and the weft yarn 3b before the tension is applied. That is, the screen plate 1 of the present embodiment is easy to improve the strength (for example, breaking strength or tearing strength) of the screen yarn 3 compared to the screen plate 1 in which the thickness of the screen yarn is changed by more than 88% by applying a predetermined tension.

[0089] Here, in order to make the thickness t of the silk screen 3 stretched on the silk screen plate 1 thinner, it is possible to consider weaving thinner warp 3a and weft 3b to make the silk screen 3, and to manufacture the silk screen plate 1 by stretching the obtained silk screen 3 on the plate frame 2 without reducing the thickness of the warp 3a and weft 3b. However, the smaller the diameter of the warp 3a and weft 3b, the easier it is to break the wire, so the thin warp 3a and weft 3b with thickness d12 and d22 are easy to break when weaving, or cannot withstand repeated printing. Therefore, in this manufacturing method, the thickness d12 and d22 of the warp 3a and weft 3b stretched on the plate frame 2 can only be made to be above the predetermined thickness that is difficult to break the wire, and there is a problem that it is difficult to make the thickness t of the silk screen 3 thinner.

[0090] On the other hand, in the manufacturing method of the screen plate 1 of the present embodiment, when the woven warp 3a and weft 3b (screen yarn 3) are stretched on the plate frame 2, the thickness of the screen yarn 3 is reduced by reducing the thickness of the warp 3a and weft 3b. Therefore, the thickness d12 and d22 of the warp 3a and weft 3b stretched on the plate frame 2 can be made thinner than the predetermined thickness at which the wire breakage is unlikely to occur. Therefore, the manufacturing method of the screen plate 1 involved in the present embodiment is easier to make the thickness t of the screen yarn 3 thinner than the above-mentioned manufacturing method, and it is easier to form a printed coating with a thinner film thickness (for example, a printed coating with a film thickness of less than 1 μm).

[0091] Next, a modification of the screen plate 1 of the present embodiment is described. In this modification, the screen yarn 3 is heated and stretched on the plate frame 2, so that the warp yarn 3a and the weft yarn 3b are stretched in the length direction, and the total thickness (d12+d22) of the warp yarn 3a and the weft yarn 3b is reduced to a thickness of less than 88%. That is, the screen plate 1 of this modification can be manufactured as follows: the screen yarn 3 is formed by weaving the warp yarn 3a and the weft yarn 3b, and a predetermined tension is applied to the screen yarn 3 while the screen yarn 3 is heated, and the screen yarn 3 is stretched on the plate frame 2 in a state where the predetermined tension is applied.

[0092] The heating temperature of the mesh gauze 3 depends on the material of the wire, the diameter of the wire, the predetermined tension applied to the mesh gauze 3, etc., and therefore cannot be determined uniquely, but may be set to 180° C. or less, for example.

[0093] The warp yarns 3a and weft yarns 3b that can be used in this modification are not particularly limited as long as they are synthetic fibers that can be stretched in the length direction when the heated screen yarn 3 is laid on the plate frame 2 and make the thickness t of the screen yarn 3 less than 88% of the thickness of the screen yarn 3 without tension. For example, synthetic fibers formed of polyesters such as polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polyethylene naphthalate (PEN), liquid crystal polyester, nylon, polyphenylsulfone (PPS), polyetheretherketone (PEEK), and synthetic fibers formed by combining two or more of these can be used.

[0094] The screen plate 1 of this variant has the same effect as the screen plate 1 of the present embodiment. Specifically, since the thickness t of the screen yarn 3 stretched on the plate frame 2 is less than 88% of the thickness of the screen yarn 3 without tension, the thickness t of the screen yarn 3 is easy to be thinned, and a printed coating with a thin film thickness (for example, a printed coating with a film thickness of less than 1 μm) is easy to be formed. In addition, when the screen yarn 3 is stretched on the plate frame 2, the thickness d12 and d22 of the screen plate 1 of this variant are reduced while the thickness d12 and d22 are stretched in the length direction, so the expansion of the warp 3a and the weft 3b in the width direction is suppressed. Therefore, it is easy to fill the ink 12 into the opening 3c, thereby improving the printing accuracy. In addition, the manufacturing method of the screen plate 1 of this variant has the same effect as the manufacturing method of the screen plate 1 of the present embodiment. Specifically, in the manufacturing method of the screen plate 1 of this modified example, when the woven warp yarn 3a and weft yarn 3b (screen yarn 3) are stretched on the plate frame 2, the thickness of the warp yarn 3a and weft yarn 3b is reduced, thereby reducing the thickness of the screen yarn 3, so that the thickness d12 and d22 of the warp yarn 3a and weft yarn 3b stretched on the plate frame 2 can be made thinner than the predetermined thickness that is not easy to break. Therefore, it is easy to manufacture the screen plate 1 with a thin screen yarn 3 of thickness t. In addition, if the screen yarn 3 is stretched on the plate frame 2 while being heated, the warp yarn 3a and weft yarn 3b are easily plastically deformed. Therefore, from the viewpoint of continuously maintaining a state of improving printing accuracy, it is preferred to stretch the screen yarn 3 on the plate frame 2 without heating the screen yarn 3.

[0095] Example

[0096] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples.

[0097] (Example 1)

[0098] A core-sheath composite fiber (manufactured by Kurare Co., Ltd., product name Vecry) including a core portion composed of polyarylate (liquid crystal polyester) and a sheath portion composed of a thermoplastic polymer as a component of the sea portion and polyarylate (liquid crystal polyester) as a component of the island portion was prepared as a synthetic fiber monofilament. The cross-sectional shape of the core-sheath composite fiber is a perfect circle with a diameter of 23 μm. The core-sheath composite fiber is used as a warp 3a and a weft 3b, and is flat-woven in a manner that the warp 3a and the weft 3b have a density of 380 meshes to obtain a silk screen yarn 3 (hereinafter also referred to as a "raw roll").

[0099] The four sides of the prepared silk screen 3 (original roll) were clamped by the clamp of the tensioner, and the silk screen 3 was set on the 320mm×320mm aluminum plate frame 2 under the condition of applying a tension of 36N / cm, thereby obtaining the silk screen 1 of Example 1. In the silk screen 1 of Example 1, the deviation angles of the warp 3a and the weft 3b were both 22.5 degrees.

[0100] (Example 2)

[0101] Prepare nylon fiber as a synthetic fiber monofilament. The cross-sectional shape of the fiber is a perfect circle with a diameter of 30 μm. Use the fiber as the warp 3a and the weft 3b, and weave the warp 3a and the weft 3b in a manner that the mesh density is 305 to obtain a silk screen yarn 3 (hereinafter also referred to as "original roll").

[0102] The four sides of the prepared silk screen 3 (original roll) were clamped by the clamp of a tensioning machine, and the silk screen 3 was stretched on a 320mm×320mm aluminum frame 2 under a tension of 21N / cm, thereby obtaining the silk screen 1 of Example 2. In the silk screen 1 of Example 2, the deviation angles of the warp 3a and the weft 3b were both 22.5 degrees.

[0103] (Example 3)

[0104] As in Example 1, a core-sheath type composite fiber (manufactured by Kurare Co., Ltd., product name Vecry) including a core portion composed of polyarylate (liquid crystal polyester) and a sheath portion composed of a thermoplastic polymer as a component of the sea portion and polyarylate (liquid crystal polyester) as a component of the island portion was prepared as a synthetic fiber monofilament. The cross-sectional shape of the core-sheath type composite fiber is a perfect circle with a diameter of 23 μm. The core-sheath type composite fiber is used as a warp 3a and a weft 3b, and is plain woven in a manner that the warp 3a and the weft 3b have a density of 330 meshes to obtain a silk screen yarn 3 (hereinafter also referred to as a "raw roll").

[0105] The four sides of the prepared silk screen 3 (original roll) were clamped by the clamp of a tensioning machine, and the silk screen 3 was set on a 320mm×320mm aluminum plate frame 2 under a tension of 36N / cm, thereby obtaining the silk screen 1 of Example 3. In the silk screen 1 of Example 3, the deviation angles of the warp 3a and the weft 3b were both 22.5 degrees.

[0106] (Comparative Example 1)

[0107] The screen gauze 3 (original roll) woven in Example 1 is passed between two metal rollers set at 120°C and 300N / cm to obtain a pressurized and heated screen gauze 3 (hereinafter also referred to as "pressurized and heated original roll"). The screen plate 1 of Comparative Example 1 is obtained under the same conditions as in Example 1 except that the pressurized and heated screen gauze 3 is stretched on the plate frame 2.

[0108] Regarding the screen plate 1 of the embodiment, the thickness of the screen gauze 3 stretched on the original roll and the plate frame 2 (hereinafter also referred to as "gauze thickness") was measured and the opening ratio was calculated. In addition, the ratio of the gauze thickness of the screen gauze 3 stretched on the plate frame 2 to the gauze thickness of the original roll (hereinafter also referred to as "gauze thickness ratio") (%) was calculated. The results are shown in Table 1 described below.

[0109] Regarding the screen plate 1 of the comparative example, the yarn thickness of the original roll, the original roll after pressure heating, and the screen yarn 3 stretched on the plate frame 2 was measured and the opening rate was calculated. In addition, the ratio of the yarn thickness of the screen yarn 3 stretched on the plate frame 2 to the yarn thickness of the original roll after pressure heating (hereinafter also referred to as "yarn thickness ratio") (%) was calculated. The results are shown in Table 1 described below.

[0110] The yarn thickness was measured with a thickness meter (MG-4, manufactured by Protec Co., Ltd.). The opening ratio was determined by measuring the widths d11 and d21 of the warp yarns 3a and weft yarns 3b, the interval w1 between adjacent warp yarns 3a, and the interval w2 between adjacent weft yarns 3b with a length measuring machine (DR-55-F, manufactured by Dainippon Screen Manufacturing Co., Ltd.) and using the above formula (1).

[0111] Table 1

[0112]

[0113] For the screen plate 1 of the embodiment and the comparative example, a photosensitive resin (manufactured by Oji TAC Co., Ltd., product name: AX-81) was applied to the screen gauze 3 using a barrel, and the applied photosensitive resin was dried. The application and drying of the photosensitive resin were repeated to form a shielding film 10 with a thickness of about 5 μm. A 40 mm×40 mm mask 11 was attached to the shielding film 10, and an opening 10a of 40 mm×40 mm was formed on the shielding film 10 by exposure and development.

[0114] As can be seen from Table 1, the opening ratio of the screen plate 1 of the embodiment is 31% or more. On the other hand, the opening ratio of the screen plate 1 of the comparative example is 25%. As can be seen from the results, the screen plate 1 of the embodiment can easily form a printed coating with uniform film thickness, and the printing accuracy can be improved because more ink 12 can be filled into the opening 3c than the screen plate of the comparative example.

[0115] (Example 4)

[0116] The four sides of the silk screen 3 used in Example 1 are clamped with a tensioner clamp, and the silk screen 3 is stretched on a 320 mm × 320 mm aluminum frame 2 under a tension of 36 N / cm to obtain a silk screen plate 1. For the obtained silk screen plate 1, a photosensitive resin (manufactured by Prince TAC Co., Ltd., product name: AX-81) is applied to the silk screen 3 using a barrel, and the applied photosensitive resin is dried. The photosensitive resin is repeatedly applied and dried to form a masking film 10 with a thickness of about 5 μm. A 120 mm × 120 mm mask 11 is pasted on the masking film 10, and an opening 10a of 120 mm × 120 mm is formed on the masking film 10 by exposure and development to obtain the silk screen plate 1 of Example 4.

[0117] (Comparative Example 2)

[0118] The screen plate 1 of Comparative Example 2 was obtained by the same method as in Example 4 except that the screen gauze 3 used in Example 4 was stretched on an aluminum plate frame 2 of 320 mm×320 mm under a tension of 20 N / cm.

[0119] (printing accuracy)

[0120] Printing was performed using the screen plate 1 of Example 4 and Comparative Example 2, and the printing accuracy was evaluated. In the 120 mm × 120 mm printing pattern, when the 100th printing pattern was within 120 mm ± 30 μm × 120 ± 30 μm, the printing accuracy was set to good, and when it was not within 120 mm ± 30 μm × 120 ± 30 μm, the printing accuracy was set to poor. In addition, the gap (the distance between the screen gauze 3 and the printed object) was the minimum value that could separate the plates, which was 0.7 mm in Example 4 and 1.8 mm in Comparative Example 2.

[0121] The yarn thickness measurement results and printing accuracy of Example 4 and Comparative Example 2, as well as the calculated Young's modulus are shown in Table 2. In addition, the Young's modulus can be obtained as follows: in a state where the tension applied by being stretched on the plate frame 2 is applied to the screen yarn 3, the distance between the chucks is 200 mm, the tension speed is 100 mm / min, the screen yarn 3 is stretched in the longitudinal direction (Y direction) and the transverse direction (X direction), and each Young's modulus calculated from the tangent of the rising part of the obtained load-elongation curve is averaged.

[0122] Table 2

[0123]

[0124] As can be seen from Table 2, the evaluation result of the printing accuracy of the screen plate 1 of the example is good, and the evaluation result of the printing accuracy of the screen plate 1 of the comparative example is poor. From these results, it can be seen that the screen plate 1 of the example can improve the printing accuracy.

Claims

1. A screen printing plate, characterized in that: include: Frame; as well as Silk screen yarn is formed by using warp and weft yarns woven into a predetermined fabric structure. The silk screen yarn is stretched on the frame under a predetermined tension. The warp and weft yarns are stretched by the predetermined tension applied to the mesh yarn, Due to the elongation of the warp and weft yarns, the thickness of the screen yarn stretched on the frame is reduced to less than 88% of the thickness of the screen yarn without tension, and the Young's modulus of the screen yarn stretched on the frame is 2000N / mm 2 above, The diameter of the warp and weft before weaving is less than 33 μm. The warp and weft threads include liquid crystal polymers, and The predetermined tension is 21 N / cm to 36 N / cm.

2. The screen plate according to claim 1, characterized in that: The thickness of the screen gauze stretched on the plate frame is at least 70% of the thickness of the screen gauze without tension applied thereto.

3. The screen plate according to claim 1 or 2, characterized in that: The warp threads and the weft threads are monofilaments.

4. A method for manufacturing a screen plate, characterized in that: include: applying a predetermined tension to a silk screen yarn formed by using warp yarns and weft yarns woven into a predetermined fabric structure, so as to stretch the warp yarns and weft yarns by the predetermined tension applied to the silk screen yarn, and stretching the silk screen yarn on a plate frame, Due to the elongation of the warp and weft yarns, the thickness of the silk screen yarn stretched on the frame is reduced to less than 88% of the thickness of the silk screen yarn without tension, and the Young's modulus of the silk screen yarn stretched on the frame is 2000N / mm 2 Above, among which The diameter of the warp and weft before weaving is less than 33 μm. The warp and weft yarns include liquid crystal polymers, and The predetermined tension is 21 N / cm to 36 N / cm.

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