Printed Circuit Board

Abstract

The present application provides a printing substrate including a printing pattern and / or a printing line that has excellent thickness uniformity and straightness, is free from edge top defects, and is formed on a substrate that is repeatedly folded and is not damaged even when exposed to repeated folding; a screen printing ink capable of forming the printing substrate; and a printing method using the ink.

Description

[Technical field]

[0001] This application claims priority based on Korean Patent Application No. 10-2020-0102746 filed on August 14, 2020, and the contents disclosed in the Korean patent application are incorporated herein by reference.

[0002] The present application relates to a printing substrate, a screen printing ink and a screen printing method. [Background technology]

[0003] Screen printing is a printing method in which ink is applied to a screen mask (printing plate) and then pushed out with a squeegee to transfer the print pattern onto the substrate.

[0004] In the screen printing process, a drying and / or curing process may be performed after the ink is transferred to the substrate. Since the ink has a certain degree of fluidity after being transferred to the substrate and before the drying and / or curing process is completed, ink bleeding may occur. This ink bleeding may reduce the thickness uniformity and straightness of the print pattern and may cause edge top defects.

[0005] The thickness uniformity indicates how uniform the thickness is when the printed pattern is observed from the side, and the straightness indicates how straight the edges are when the printed pattern is observed from above.

[0006] In addition, the edge top defect is a defect in which the edge of the printed pattern protrudes like a shoulder when the printed pattern is observed from the side. It is presumed that such edge top defects occur when the transferred ink dries and / or hardens, and as a result, the solid content of the ink moves to the area where the solvent evaporates faster, inducing a deviation in surface tension.

[0007] For stable screen printing, the above problems must be solved.

[0008] In particular, when screen printing is used to form a print pattern having a relatively narrow width and low height, such as a bezel pattern, the above defects need to be precisely controlled to a higher level.

[0009] In addition, when a screen printing pattern such as a bezel pattern is formed on a printed substrate (e.g., a cover substrate for a foldable mobile phone) that is exposed to repeated folding during use, the printed pattern is required to be stably maintained without being damaged even under repeated folding. Summary of the Invention [Problem to be solved by the invention]

[0010] The present application provides a printing substrate, a screen printing ink, and a screen printing method. The present application can provide a printing substrate having a printing pattern that has excellent thickness uniformity and straightness, is free of edge top defects, and is not damaged even when it is formed on a substrate that is repeatedly folded and exposed to repeated folding, and an ink and a printing method that can form the printing pattern.

[0011] In addition, the present application also provides the above advantages when the print pattern is formed to have a relatively narrow width and / or height. [Means for solving the problem]

[0012] In one example, the present application relates to printed circuit boards.

[0013] The print substrate can include, for example, a substrate; and a printed pattern formed on the substrate.

[0014] In the present application, the specific types of the printed pattern and the substrate are not particularly limited. According to the present application, the printed pattern can be formed to have excellent thickness uniformity and straightness and to be free of edge top defects. In addition, even when the printed pattern is exposed to repeated folding, etc., and / or the printed pattern is formed to have a relatively narrow width and / or low height, the excellent thickness uniformity and straightness are maintained and no edge top defects occur.

[0015] Therefore, the printed pattern and substrate may be any type of printed pattern and substrate that requires the above properties.

[0016] In one example, the printing pattern may be a bezel pattern. Figure 1 shows a form of a bezel pattern (B) according to one example of the present application.

[0017] The type of substrate in the printed substrate is not particularly limited and may be selected according to the purpose. For example, the printed substrate may be a cover laminate for a touch panel, and in this case, a general substrate used in the manufacture of a cover laminate for a touch panel may be used as the substrate.

[0018] In addition, when the printed substrate is a cover laminate for a touch panel, the printed substrate may further include a pressure-sensitive adhesive layer or an adhesive layer disposed on the printed pattern and a cover substrate attached by the pressure-sensitive adhesive layer or the adhesive layer.

[0019] FIG. 2 shows an example of such a structure, including a substrate 400 , a printed pattern (eg, a bezel pattern) 300 , the adhesive or glue layer 200 and a cover substrate 100 .

[0020] In the laminate, the types of the substrate, the pressure-sensitive adhesive layer, the adhesive layer and / or the cover substrate are not particularly limited, and known materials may be used.

[0021] The printing pattern may include one or more printing lines, each of which is a unit printing layer that constitutes the printing pattern.

[0022] For example, the printing pattern (bezel pattern B) in Figure 1 includes a printed line from approximately point I to approximately point II, a printed line from approximately point II to approximately point III, a printed line from approximately point III to approximately point IV, and a printed line from approximately point IV to approximately point I.

[0023] Such a printing line may have a substantially straight line shape. In this case, the straight line shape may be a completely straight line shape or may be an approximately straight line shape. For example, as long as the printing line has a straightness as described below, it may be called a straight line shape in this application even if it is not a completely straight line shape.

[0024] The printed lines and / or printed patterns may have excellent thickness uniformity.

[0025] For example, the printed lines and / or printed patterns may have a thickness uniformity of 0.6 μm or less. The thickness uniformity is the difference between the maximum thickness and the minimum thickness of the central thickness region of the printed lines and / or printed patterns measured by the method described in the Examples below. In other examples, the thickness uniformity may be about 0.59 μm or less, 0.58 μm or less, 0.57 μm or less, 0.56 μm or less, 0.55 μm or less, 0.54 μm or less, 0.53 μm or less, 0.52 μm or less, 0.51 μm or less, 0.5 μm or less, 0.49 μm or less, 0.48 μm or less, 0.47 μm or less, 0.46 μm or less, 0.45 μm or less, 0.44 μm or less, or 0.43 μm or less. The lower the thickness uniformity value, the better the thickness uniformity of the printed lines and printed patterns, so the lower limit is not particularly limited. For example, the thickness uniformity may be, in other examples, about 0 μm or more, 0.1 μm or more, 0.2 μm or more, 0.3 μm or more, or 0.4 μm or more.

[0026] The printed lines and / or printed patterns may not include edge top defects.

[0027] For example, the printed line and / or printed pattern may have an edge top deviation of 0.55 μm or less. The edge top deviation is an absolute value of the difference between the average thickness of the printed line or printed pattern measured in a manner described in the Examples below and the thickness of the edge of the printed line or printed pattern having the corresponding average thickness. In other examples, the edge top deviation may be about 0.54 μm or less, 0.53 μm or less, 0.52 μm or less, 0.51 μm or less, 0.50 μm or less, 0.49 μm or less, 0.48 μm or less, 0.47 μm or less, 0.46 μm or less, 0.45 μm or less, 0.44 μm or less, 0.43 μm or less, 0.42 μm or less, 0.41 μm or less, 0.40 μm or less, 0.39 μm or less, or 0.38 μm or less. The lower the edge top deviation, the less edge top defects there are in the printed lines and patterns, so the lower limit is not particularly limited. For example, the edge top deviation may be 0 μm or more, 0.1 μm or more, 0.2 μm or more, or 0.3 μm or more.

[0028] When the printing line and / or printing pattern is a straight line, the printing line and / or printing pattern may have excellent straightness. For example, the straightness of the printing line and / or printing pattern may be 50 μm or less. The straightness may be calculated by analyzing an image measured by an optical microscope, taking a distance from a specified center line to the farthest printing area (black) outside the printing area as a positive (+) and a distance from the center line to the farthest unprinted area (white) inside the printing area as a negative (-) and then averaging the positive and negative values ​​of both the outside and inside of the edge area of ​​the printing area, and a specific method will be described in the Examples. In other examples, the straightness may be 48 μm or less, 46 μm or less, 44 μm or less, 42 μm or less, 40 μm or less, 38 μm or less, 36 μm or less, 34 μm or less, 32 μm or less, 30 μm or less, 28 μm or less, or 26 μm or less. The lower the value of the straightness, the better the straightness, and therefore the lower limit is not particularly limited. For example, the straightness may be 5 μm or more, 10 μm or more, 15 μm or more, or 20 μm or more.

[0029] The width of the printed pattern or line (e.g., W in FIG. 1 in the case of a bezel pattern) may be within a range of 0.1 mm to 10 mm, and may be additionally adjusted within a range of 0.5 mm or more, 1 mm or more, or 1.5 mm or more, and / or within a range of 9 mm or less, 8 mm or less, 7 mm or less, 6 mm or less, 5 mm or less, 4 mm or less, or 3 mm or less.

[0030] The height of the printed pattern or printed line (e.g., the height of the bezel pattern) may be within a range of 0.5 μm to 10 μm. In other examples, the height may be additionally adjusted within a range of 1 μm or more, 1.5 μm or more, 2 μm or more, or 3.5 μm or more, and / or within a range of 9 μm or less, 8 μm or less, 7 μm or less, 6 μm or less, or 5 μm or less.

[0031] In the present application, even when the width and / or height of the printed pattern or printed line is formed to be relatively narrow and / or low within the above range, it is possible to form a printed pattern and / or printed line having the desired characteristics (excellent straightness and thickness uniformity, no edge top defects, excellent adhesion and durability).

[0032] The printing patterns and / or printing lines can be formed by applying the ink described below and additionally applying the printing method described below.

[0033] For example, the printed patterns and / or printed lines formed using the ink described below may include at least some of the components of the ink.

[0034] For example, the printed patterns and / or printed lines may include at least a polymeric binder and a fluorosurfactant.

[0035] Specific types of the polymer binder and fluorosurfactant will be described in the description of the ink below.

[0036] The content of the polymer binder and the fluorosurfactant in the printed pattern and / or printed line is also approximately the same as the content in the ink, which will be described later.

[0037] For example, the fluorosurfactant may be included in the print pattern and / or print line in an amount of 0.25 to 2.5 parts by weight relative to 100 parts by weight of the polymer binder, and other examples of this ratio include 0.26 parts by weight or more, 0.27 parts by weight or more, 0.28 parts by weight or more, 0.29 parts by weight or more, 0.3 parts by weight or more, 0.35 parts by weight or more, 0.4 parts by weight or more, 0.45 parts by weight or more, 0.5 parts by weight or more, 0.55 parts by weight or more, 0.6 parts by weight or more, 0.65 parts by weight or more, 0.7 parts by weight or more, 0.75 parts by weight or more, 0.8 parts by weight or more, 0.85 parts by weight or more, 0.9 parts by weight or more, 0.95 parts by weight or more, 1 part by weight or more, 1.2 parts by weight or more, 1.4 parts by weight or more, and the like. The amount of the carboxylic acid or fatty acid may be additionally adjusted within the range of 1.6 parts by weight or more, 1.8 parts by weight or more, or 2 parts by weight or more, and / or 2.4 parts by weight or less, 2.3 parts by weight or less, 2.2 parts by weight or less, 2.1 parts by weight or less, 2 parts by weight or less, 1.8 parts by weight or less, 1.6 parts by weight or less, 1.4 parts by weight or less, 1.2 parts by weight or less, 1 part by weight or less, 0.95 parts by weight or less, 0.9 parts by weight or less, 0.85 parts by weight or less, 0.8 parts by weight or less, 0.75 parts by weight or less, 0.7 parts by weight or less, 0.65 parts by weight or less, 0.6 parts by weight or less, 0.55 parts by weight or less, 0.5 parts by weight or less, 0.45 parts by weight or less, 0.4 parts by weight or less, 0.35 parts by weight or less, or 0.3 parts by weight or less.

[0038] The printing patterns and / or printing lines may contain the same components as those contained in the ink described below, and the ratio thereof may be adjusted within the ranges mentioned in the description of the ink.

[0039] For example, the print pattern and / or print line may include a colorant for imparting optical density as an additional component. At this time, the specific type of the colorant to be applied is the same as that described in the ink section below. The colorant may be applied in a ratio of 20 to 90 parts by weight relative to 100 parts by weight of the polymer binder, which may be adjusted in consideration of the desired optical density. In order to appropriately secure the desired physical properties, the ratio may be additionally adjusted within the range of, for example, 25 parts by weight or more, 30 parts by weight or more, 35 parts by weight or more, 40 parts by weight or more, 45 parts by weight or more, 50 parts by weight or more, 55 parts by weight or more, 60 parts by weight or more, 65 parts by weight or more, 70 parts by weight or more, 75 parts by weight or more, or 80 parts by weight or more, and / or 85 parts by weight or less, 80 parts by weight or less, 75 parts by weight or less, 70 parts by weight or less, 65 parts by weight or less, 60 parts by weight or less, 55 parts by weight or less, 50 parts by weight or less, 45 parts by weight or less, or 40 parts by weight or less.

[0040] The printed pattern and / or printed line may contain a solvent component contained in the ink as an additional component, which will be described later. Although such a solvent component is usually removed by evaporation during the printing process, it may still be present in a small amount in the printed pattern and / or printed line.

[0041] Thus, the printed patterns and / or printed lines may include a compound of Formula 1, as described in the Ink section below.

[0042] The printed patterns and / or printed lines are formed by ink, and since the solvent component (e.g., the compound of Chemical Formula 1) contained in the ink may be removed by evaporation or the like during the formation process, the ratio of the polymer binder in the printed patterns and / or printed lines may be different from the ratio in the ink.

[0043] For example, the ratio of the polymer binder in the printed pattern and / or printed line may be within the range of about 50 to 95% by weight, which may be additionally adjusted within the range of about 55% by weight or more, 60% by weight or more, 65% by weight or more, 70% by weight or more, 75% by weight or more, 80% by weight or more, 85% by weight or more, or 90% by weight or more and / or within the range of about 90% by weight or less, 85% by weight or less, 80% by weight or less, 75% by weight or less, 70% by weight or less, 65% by weight or less, 60% by weight or less, or 55% by weight or less.

[0044] In the following, the ink applied to form the printing patterns and / or printing lines will be described. The ink may be a screen printing ink. Therefore, the ink may be applied to a screen printing process.

[0045] The ink of the present application includes at least a polymer binder and a fluorosurfactant. The ink of the present application may be an ink that is cured by drying (hereinafter, may be referred to as a dry-curing type or a heat-curing type). The category of the ink that is cured by drying does not include ink that is cured by irradiation with energy rays such as ultraviolet rays.

[0046] The type of the polymer binder that can be used in the present application is not particularly limited. In the industry, various polymer binders that can be used in screen printing inks and exhibit suitable viscosity characteristics and suitable adhesion and durability to a printed substrate are known, and any of such known polymer binders can be used in the present application.

[0047] Examples of such polymer binders include polyesters such as polyester, urethane-modified polyester, epoxy-modified polyester, and acrylic-modified polyester, or various modified polyesters, vinyl chloride-vinyl acetate copolymer resins, butyral resins, polyether urethane resins, polyester urethane resins, polycarbonate urethane resins, epoxy resins, phenolic resins, acrylic resins, polyamides, polyamideimides, polyolefins, chlorinated polyolefins, chlorinated rubbers, melamine resins, urea resins, ethyl cellulose resins, nitrocellulose resins, modified cellulose resins such as cellulose acetate butyrate (CAB) and cellulose acetate propionate (CAP), rosin resins, maleic acid resins, natural resins, and / or alkyd resins.

[0048] Among these known binders, those that can be combined with the fluorosurfactant in the present application to more effectively achieve the desired properties are polyester-based binders such as polyesters, urethane-modified polyesters, epoxy-modified polyesters, acrylic-modified polyesters, and other polyesters or various modified polyesters, but the binders that can be used in the present application are not limited thereto.

[0049] The polymer binder may be contained in the ink at a ratio of about 20 to 40% by weight. Other examples of the ratio may be about 21% by weight or more, about 22% by weight or more, about 23% by weight or more, about 24% by weight or more, or about 25% by weight or more, or about 39% by weight or less, about 38% by weight or less, about 37% by weight or less, about 36% by weight or less, or about 35% by weight or less. When the ink containing the polymer binder is combined with a fluorosurfactant described below at an appropriate ratio under such a ratio, the flow characteristics (viscosity, thixotropy, etc.) of the ink are appropriately adjusted, the movement of solids and surface tension during the drying and / or curing process of the ink are controlled at an appropriate level, and a printed pattern and / or printed line having excellent thickness uniformity and straightness, no edge top defects, and no damage even when repeatedly folded can be formed.

[0050] The ink further includes a fluorosurfactant, which, when included in an appropriate ratio, appropriately adjusts the flow characteristics (viscosity, thixotropy, etc.) of the ink and controls the movement of solids and surface tension during the ink drying and / or curing process, allowing the formation of a printed pattern with excellent thickness uniformity and straightness, no edge top defects, and no damage even when repeatedly folded.

[0051] The type of fluorosurfactant is not particularly limited, and for example, known fluorosurfactants such as fluoroalkyl carboxylates, fluoroalkyl phosphates, fluoroalkyl sulfonates, fluoroalkyl ethylene oxide derivatives, and fluoroalkyl ammonium salts can be used. As the fluorosurfactant, ionic surfactants or nonionic surfactants can be used, and preferably nonionic surfactants can be used. Such surfactants are known as F-251, F-444, F-477, F-510, F-552, F-553, F-554, F-555, F-556, F-557, F-558, F-559, F-560, F-561, F-562, F-563, F-565, F-567, F-568, F-569, F-570, or F-571 manufactured by DIC Corporation.

[0052] The fluorosurfactant may be included in the ink in an amount of 0.25 to 2.5 parts by weight per 100 parts by weight of the polymer binder. At this ratio, the flow properties (viscosity, thixotropy, etc.) of the ink are appropriately adjusted, the movement of solids and surface tension during the drying and / or curing process of the ink are controlled at appropriate levels, and printed patterns and / or printed lines with excellent thickness uniformity and straightness, no edge top defects, and no damage even when repeatedly folded, may be formed.

[0053] Other examples of the ratio of the surfactant include 0.26 parts by weight or more, 0.27 parts by weight or more, 0.28 parts by weight or more, 0.29 parts by weight or more, 0.3 parts by weight or more, 0.35 parts by weight or more, 0.4 parts by weight or more, 0.45 parts by weight or more, 0.5 parts by weight or more, 0.55 parts by weight or more, 0.6 parts by weight or more, 0.65 parts by weight or more, 0.7 parts by weight or more, 0.75 parts by weight or more, 0.8 parts by weight or more, 0.85 parts by weight or more, 0.9 parts by weight or more, 0.95 parts by weight or more, 1 part by weight or more, 1.2 parts by weight or more, 1.4 parts by weight or more, 1.6 parts by weight or more, 1.8 parts by weight or more, or 2 parts by weight or more. parts by weight or more, or may be about 2.4 parts by weight or less, 2.3 parts by weight or less, 2.2 parts by weight or less, 2.1 parts by weight or less, 2 parts by weight or less, 1.8 parts by weight or less, 1.6 parts by weight or less, 1.4 parts by weight or less, 1.2 parts by weight or less, 1 part by weight or less, 0.95 parts by weight or less, 0.9 parts by weight or less, 0.85 parts by weight or less, 0.8 parts by weight or less, 0.75 parts by weight or less, 0.7 parts by weight or less, 0.65 parts by weight or less, 0.6 parts by weight or less, 0.55 parts by weight or less, 0.5 parts by weight or less, 0.45 parts by weight or less, 0.4 parts by weight or less, 0.35 parts by weight or less, or 0.3 parts by weight or less.

[0054] The ink of the present application may contain other components in addition to the above components, for example, the ink may contain a solvent component to disperse the polymer binder, surfactant, etc.

[0055] The solvent component is not particularly limited, and any known solvent component applicable to inks can be used.

[0056] As an example, in the present application, a compound of the following Chemical Formula 1 may be applied as the solvent component so that suitable flow properties (viscosity, thixotropy, etc.) are ensured, the evaporation rate during the drying and / or curing process of the ink is controlled at an appropriate level, and the movement and surface tension of solids are controlled at an appropriate level.

[0057] [ka]

[0058] R in Chemical Formula 1 1is a hydrogen atom, an alkyl group, or an alkylcarbonyl group, and L 1 is an alkylene group, and R 2 is an alkyl group or a hydrogen atom, and n is a number within the range of 1 to 10.

[0059] R in Chemical Formula 1 1 may be, for example, a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, 1 to 16 carbon atoms, 1 to 12 carbon atoms, 1 to 8 carbon atoms, or 1 to 4 carbon atoms, or an alkylcarbonyl group having an alkyl group having 1 to 20 carbon atoms, 1 to 16 carbon atoms, 1 to 12 carbon atoms, 1 to 8 carbon atoms, or 1 to 4 carbon atoms. The alkyl group may be linear, branched, or cyclic, and may be optionally substituted with one or more substituents.

[0060] In chemical formula 1, L 1 As another example, it may be an alkylene group having 1 to 20 carbon atoms, 1 to 16 carbon atoms, 1 to 12 carbon atoms, 1 to 8 carbon atoms, or 1 to 4 carbon atoms. The alkylene group may be linear, branched, or cyclic, and may be optionally substituted with one or more substituents.

[0061] R in Chemical Formula 1 2 may be a hydrogen atom or an alkyl group having 1 to 20 carbon atoms, 1 to 16 carbon atoms, 1 to 12 carbon atoms, 1 to 8 carbon atoms, or 1 to 4 carbon atoms. The alkyl group may be linear, branched, or cyclic, and may be optionally substituted with one or more substituents.

[0062] In Formula 1, n may be 9 or less, 8 or less, 7 or less, 6 or less, 5 or less, 4 or less, 3 or less, or 2 or less, as other examples.

[0063] Compounds with such structures can be combined with the polymer and fluorosurfactant to more effectively ensure the desired ink properties.

[0064] The compound of Formula 1 may be included in the ink in an amount of 100 to 300 parts by weight based on 100 parts by weight of the polymer binder. Other examples of the ratio include 110 parts by weight or more, 120 parts by weight or more, 130 parts by weight or more, 140 parts by weight or more, 150 parts by weight or more, 160 parts by weight or more, 170 parts by weight or more, 180 parts by weight or more, 190 parts by weight or more, 200 parts by weight or more, 210 parts by weight or more, 220 parts by weight or more, 230 parts by weight or more, or 240 parts by weight or more, or 290 parts by weight or less, 280 parts by weight or less, 270 parts by weight or less, 260 parts by weight or less, 250 parts by weight or less, 240 parts by weight or less, 230 parts by weight or less, 220 parts by weight or less, 210 parts by weight or less, 200 parts by weight or less, 190 parts by weight or less, 180 parts by weight or less, 170 parts by weight or less, 160 parts by weight or less, 150 parts by weight or less, 140 parts by weight or less, 130 parts by weight or less, 120 parts by weight or less, or 110 parts by weight or less.

[0065] In order to ensure proper physical properties, the ratio of the compound of Formula 1 in the ink may be adjusted to less than 70% by weight. In other examples, the ratio may be 69% by weight or less, 68% by weight or less, 67% by weight or less, 66% by weight or less, 65% by weight or less, 64% by weight or less, 63% by weight or less, 62% by weight or less, 61% by weight or less, or 60% by weight or less, or 30% by weight or more, 31% by weight or more, 32% by weight or more, 33% by weight or more, 34% by weight or more, 35% by weight or more, 36% by weight or more, 37% by weight or more, 38% by weight or more, 39% by weight or more, 40% by weight or more, 41% by weight or more, 42% by weight or more, 43% by weight or more, 44% by weight or more, 45% by weight or more, 46% by weight or more, 47% by weight or more, 48% by weight or more, 49% by weight or more, or 50% by weight or more.

[0066] The ink may contain additional ingredients such as colorants.

[0067] The colorant is used to impart a desired optical density to the ink, and may be applied in a ratio of, for example, 20 to 90 parts by weight relative to 100 parts by weight of the polymer binder, which may be adjusted in consideration of the desired optical density. In order to appropriately secure the desired physical properties, the ratio may be additionally adjusted within the range of, for example, 25 parts by weight or more, 30 parts by weight or more, 35 parts by weight or more, 40 parts by weight or more, 45 parts by weight or more, 50 parts by weight or more, 55 parts by weight or more, 60 parts by weight or more, 65 parts by weight or more, 70 parts by weight or more, 75 parts by weight or more, or 80 parts by weight or more, and / or 85 parts by weight or less, 80 parts by weight or less, 75 parts by weight or less, 70 parts by weight or less, 65 parts by weight or less, 60 parts by weight or less, 55 parts by weight or less, 50 parts by weight or less, 45 parts by weight or less, or 40 parts by weight or less.

[0068] As the colorant, one or more pigments, dyes or mixtures thereof can be used, and the type is not particularly limited as long as it can express the desired color.

[0069] As an example, the colorant may be a black pigment and / or dye, such as carbon black, graphite, metal oxides, and / or organic black pigments.

[0070] Examples of carbon black include SEA-ST 5HIISAF-HS, SEA-ST KH, SEA-ST 3HHAF-HS, SEA-ST NH, SEA-ST 3M, SEA-ST 300HAFLS, SEA-ST 116HMMAF-HS, SEA-ST 116MAF, SEA-ST FMFEF-HS, SEA-ST SOFEF, SEA-ST VGPF, SEA-ST SVHSRF-HS and SEA-ST SSRF (Tokai Carbon Co., Ltd.); Diagram Black II, Diagram Black N339, Diagram Black SH, Diagram Black H, Diagram LH, Diagram HA, Diagram SF, Diagram N550M, Diagram M, Diagram E, Diagram G, Diagram R, Diagram N760M, Diagram LR, #2700, #2600, #2400, #2350, #23 00, #2200, #1000, #980, #900, MCF88, #52, #50, #47, #45, #45L, #25, #CF9, #95, #3030, #3050, MA7, MA77, MA8, MA11, MA100, MA40, OIL7B, OIL9B, OIL11B, OIL30B and OIL31B (Mitsubishi Chemical Co., Ltd.); PRINTEX-U, PRINTEX-V, PR INTEX140U, PRINTEX-140V, PRINTEX-95, PRINTEX-85, PRINTEX-75, PRINTEX-55, PRINTEX-45, PRINTEX-300, PRINTEX35, PRINTEX-25, PRINTEX-200, PRINTEX-40, PRINTEX-30, PRINTEX-3, PRINTEX-A, SPECIAL BLACK-550, SPECIAL BLACK-350, SPECIAL BLACK-250, SPECIAL BLACK-100 and LAMP BLACK-101 (Degussa Corporation);RAVEN-1100ULTRA, RAVEN1080ULTRA, RAVEN-1060ULTRA, RAVEN-1040, RAVEN-1035, RAVEN-1020, RAVEN-1000, RAVEN-890H, RAVEN-890, RAVEN-88 0ULTRA, RAVEN-860ULTRA, RAVEN-850, RAVEN-820, RAVEN-790ULTRA, RAVEN-780ULTRA, RAVEN-760ULTRA, RAVEN-520, RAVEN-500, RAVEN-460, RAVE Examples of the organic black pigment include, but are not limited to, aniline black, lactam black, and perylene black series.

[0071] In addition to the above-mentioned components, the ink may further contain appropriate amounts of known additives such as antifoaming agents and diluents that are used in inks, as long as the desired properties are not impaired.

[0072] The present application also relates to a method of printing with said ink, which may be a screen printing method.

[0073] The screen printing method is not particularly limited in terms of the specific procedure as long as the ink of the present application is used, and any known screen printing method can be used.

[0074] The screen printing method is generally performed by applying ink to a printing plate on which a printing pattern made in a mesh shape is formed, placing the printing plate on a substrate to be printed, and then pushing out the ink with a squeegee or the like.

[0075] Thus, for example, the screen printing method may include transferring the screen printing ink onto a substrate through a screen printing plate.

[0076] In this process, the transfer can be accomplished by using a squeegee to push the ink onto the printing plate.

[0077] The specific conditions for this process are not particularly limited.

[0078] For example, in the above process, for proper printing, the squeegee angle may be controlled within a range of about 50 degrees to 180 degrees, and in other examples, the angle may be adjusted within a range of about 55 degrees or more, 60 degrees or more, 65 degrees or more, 70 degrees or more, 75 degrees or more, or 80 degrees or more, and / or within a range of 175 degrees or less, 170 degrees or less, 165 degrees or less, 160 degrees or less, 155 degrees or less, 150 degrees or less, 145 degrees or less, 140 degrees or less, 135 degrees or less, 130 degrees or less, 125 degrees or less, 120 degrees or less, 115 degrees or less, 110 degrees or less, 105 degrees or less, 100 degrees or less, 95 degrees or less, 90 degrees or less, 85 degrees or less, or 80 degrees or less.

[0079] In addition, the printing speed in the screen printing may be controlled within a range of about 20 to 200 mm / sec. In other examples, the printing speed may be additionally adjusted within a range of about 30 mm / sec or more, 40 mm / sec or more, 50 mm / sec or more, 60 mm / sec or more, 70 mm / sec or more, 80 mm / sec or more, 90 mm / sec or more, or 100 mm / sec or more, and / or within a range of about 190 mm / sec or less, 180 mm / sec or less, 170 mm / sec or less, 160 mm / sec or less, 150 mm / sec or less, 140 mm / sec or less, 130 mm / sec or less, 120 mm / sec or less, 110 mm / sec or less, 100 mm / sec or less, 90 mm / sec or less, 80 mm / sec or less, 70 mm / sec or less, 60 mm / sec or less, 50 mm / sec or less, or 40 mm / sec or less.

[0080] In order to form a desired print pattern, the printing speed can be controlled by the amount of the surfactant in the ink. For example, the printing speed may be controlled to be slower as the amount of the surfactant in the ink increases.

[0081] For example, the printing speed can be controlled so that the S value (unit: parts by weight mm / sec) of the following Equation 1 is within the range of 25 to 110. [Formula 1] S = R × W

[0082] In Equation 1, R is the printing speed (unit: mm / sec), and W is the part by weight of the surfactant relative to 100 parts by weight of the polymer binder in the ink.

[0083] In other examples, the S value may be additionally controlled within a range of 26 or more, 27 or more, 28 or more, or 29 or more, and / or within a range of 109 or less, 108 or less, 107 or less, 106 or less, 105 or less, 104 or less, 103 or less, 102 or less, 101 or less, 100 or less, 99 or less, 98 or less, 97 or less, 96 or less, 95 or less, 94 or less, 93 or less, 92 or less, 91 or less, 90 or less, 89 or less, 88 or less, 87 or less, 86 or less, 85 or less, 84 or less, 83 or less, 82 or less, 81 or less, or 80 or less.

[0084] In the printing method, a process of drying the transferred ink may be additionally performed after the transfer process, and the ink may be hardened during this process.

[0085] The drying conditions are not particularly limited and can be controlled through the composition of the ink used. For example, the drying can be performed at a temperature in the range of 60° C. to 200° C. for a time in the range of about 5 minutes to 2 hours.

[0086] When screen printing is performed in two or more colors, the drying may be performed after printing and before additional printing is performed, or may be performed again after the final printing, or may be performed once in the final stage after printing in two or more colors.

[0087] Screen printing may be performed in one color or in multiple stages using two or more colors. In the present application, even in the case of a pattern formed by printing two or more colors, a printed pattern having no edge top defects and excellent thickness uniformity and straightness can be formed. In addition, the printed pattern formed through the above process exhibits excellent adhesion and durability to a substrate, and can exhibit the above characteristics even on a substrate that is applied to repeated folding.

[0088] The screen printing method may be, for example, a bezel forming method, in which case a bezel pattern may be formed by the transfer process, and in this case, specific steps and conditions of the bezel forming method are the same as those of the screen printing method. Effect of the Invention

[0089] The present application can provide a printed substrate including a printed pattern and / or a printed line that has excellent thickness uniformity and straightness, is free of edge top defects, and is not damaged even when exposed to repeated folding, and can provide an ink capable of forming the printed pattern and / or the printed line, and a printing method using the same. [Brief description of the drawings]

[0090] [Figure 1] 1 is a diagram illustrating an example bezel pattern. [Diagram 2] 1 is a diagram showing a laminated structure of a printed circuit board according to an example; [Diagram 3] 1 is a schematic diagram of a method for measuring the thickness of a printed pattern; [Figure 4] 1 is a diagram showing an example of a thickness profile. [Diagram 5] 1 is a diagram showing the parts that are folded in a folding test. [Figure 6] 13 is an optical microscope image of the printed pattern after folding test. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0091] Hereinafter, the present application will be described in detail with reference to examples, but the scope of the present application is not limited to the following examples.

[0092] 1.How to measure print thickness and edge top The thickness of the screen-printed pattern was evaluated using an Alphastep Profiler (KLA Tencor D-300) (Conditions: Contact force 5 μg, Scan speed: 100 μm / sec). As shown in FIG. 3, the polymer film 400 including the screen-printed pattern 300 was laminated on the glass 10 using OCA20 to prevent distortion of the thickness of the printed pattern, and the thickness was evaluated in the length direction of the printed pattern.

[0093] By measuring the thickness of the printed pattern using this method, thickness data such as that shown in Figure 4 can be obtained (in Figure 4, the x-axis is the thickness measurement position, and the y-axis is the thickness). From the data, the average value of the central thickness area 2000 excluding the left and right sides was designated as the print thickness, and the thickness uniformity (difference between maximum and minimum thickness) was confirmed based on the difference between the maximum and minimum values ​​in the central thickness area 2000.

[0094] In addition, the occurrence of edge top defects was evaluated by checking the absolute value (edge ​​top deviation) of the difference between the higher height of the left and right sides of the thickness profile data (height of 1000 in Figure 4) and the average value, which is the printing thickness.

[0095] The average value, thickness uniformity and edge top deviation of the central thickness region 2000 were evaluated for each of the four printing lines (printing lines I to II, printing lines II to III, printing lines III to IV and printing lines IV to I in FIG. 1) of the printing pattern printed in a bezel shape as shown in FIG. 1. The average value of the central thickness region 2000 was recorded as the average value of the results for the four printing lines, and the thickness uniformity and edge top deviation were recorded as the worst result among the results for the four printing lines in the example and the best result in the comparative example.

[0096] 2.Straightness evaluation The straightness of the printed pattern was quantified by analyzing the image measured with an optical microscope. First, the printed pattern area of ​​the image was made black and the other areas (background area) were made white to create a binary image, and a horizontal line with a black:white ratio of 1:1 was designated as the center line. Next, the distance from the center line to the farthest printed area (black) outside the printed area was designated as (+), and the distance from the center line to the farthest unprinted area (white) inside the printed area was designated as (-), and the average value of (+) and (-) for both the outside and inside of the edge area of ​​the printed area was recorded as the straightness.

[0097] The straightness was evaluated for each of the four printing lines of the printing pattern printed in a bezel shape as shown in FIG. 1 (printing lines I to II, printing lines II to III, printing lines III to IV, and printing lines IV to I in FIG. 1). In the examples, the worst result among the results for the four printing lines was recorded, and in the comparative examples, the best result was recorded.

[0098] 3. Optical Density Assessment The optical density was evaluated using a known optical density measuring device (X-rite 341C).

[0099] 4. Folding characteristics The folding characteristics were evaluated by folding the polymer film with the bezel print pattern as shown in Figure 5 200,000 times so that the area indicated by F in Figure 5 was folded, and then checking for the occurrence of cracks with the naked eye and an optical microscope. The folding was performed at a curvature of 2.5R and a speed of 1Hz (1 time per second).

[0100] Example 1. The screen printing ink was prepared by mixing FR260C-1 (manufactured by Asahi Chemical Co.), an ink containing a polyester resin binder, and F-571 (manufactured by DIC Co.), a fluorine-based surfactant.

[0101] The FR260C-1 ink contains 25 to 35% by weight of polyester binder, 50 to 60% by weight of diethylene glycol monoethyl ether acetate, 10 to 20% by weight of carbon powder (CAS No. 1333-86-4), 2% by weight or less of an anti-foaming agent, and 2% by weight or less of other additives, and the F-571 is a fluorine-based nonionic surfactant.

[0102] The ink was prepared by mixing the FR260C-1 (manufactured by Asahi Chemical Co., Ltd.) ink with a fluorosurfactant (F-571 (manufactured by DIC Co., Ltd.)) at a weight ratio of 100:0.5 (FR260C-1:F-571). The FR260C-1 contains 25 to 35% by weight of polyester binder, so the weight ratio of the surfactant to 100 parts by weight of the binder is about 1.43 to 2 parts by weight.

[0103] The bezel was printed on a polymer film, f-PET film (New polyester film, manufactured by MCC (Mitsubishi Chemical), thickness: 50 μm) by screen printing using the prepared ink. The bezel printing pattern was printed as shown in FIG.

[0104] A screen printing plate of Poly catex 460 mesh was used as the screen printing plate. A pattern was formed on the screen printing plate so that the bezel pattern shown in FIG. 1 could be transferred to the polymer film, and the printing width of the bezel (W in FIG. 1) was about 2 mm. The printing plate was placed on the polymer film, the ink prepared was applied onto the printing plate, and pressure was applied to transfer the ink onto the polymer film. In this process, the squeegee angle was adjusted to about 80 degrees, the distance between the printing plate and the polymer film substrate, which the squeegee contacts, was about 3 mm, and the printing speed was controlled to about 40 mm / sec. After printing as described above, the printing pattern was dried at 100°C for about 14 minutes (one-color printing). Then, additional printing was performed on the dried printing pattern in the same way, and it was again maintained at 100°C for about 14 minutes (two-color printing). After the two-color printing, the printing thickness was about 3.7 μm. Then, a cover window (thickness: about 70 μm) was laminated using a known OCA (Optical Clear Adhesive) with a thickness of about 25 μm to produce a laminate including a cover window 100, an OCA 200, a bezel printing pattern 300 and a polymer film 400 as shown in FIG. 2.

[0105] Example 2. When preparing the screen printing ink, the weight ratio of FR260C-1 (manufactured by Asahi Chemical Co., Ltd.) ink to fluorosurfactant (F-571) was set to 100:0.1 (FR260C-1:F-571). The FR260C-1 contains 25-35% by weight of polyester binder, so the weight ratio of the surfactant to 100 parts by weight of the binder is about 0.29-0.4 parts by weight.

[0106] Thereafter, screen printing was performed in the same manner as in Example 1 to manufacture the structure shown in FIG. 2, except that the printing speed was adjusted to about 100 mm / sec, and the printing thickness was about 4.7 μm.

[0107] Comparative Example 1 Screen printing was carried out in the same manner as in Example 1 using only FR260C-1 (Asahi Chemical) ink without mixing any fluorine-based surfactant, to manufacture a structure as shown in FIG.

[0108] Comparative Example 2 Screen printing was performed in the same manner as in Example 1 to manufacture the structure shown in Figure 2, except that an ink prepared by mixing FR260C-1 (manufactured by Asahi Chemical Co.) ink and a fluorine-based surfactant (F-571) in a weight ratio of 100:0.01 (FR260C-1:F-571) was used. Since the FR260C-1 contains 25 to 35% by weight of polyester binder, the weight ratio of the surfactant to 100 parts by weight of the binder is about 0.029 to 0.04 parts by weight.

[0109] Comparative Example 3. Screen printing was performed in the same manner as in Example 1 to manufacture the structure shown in Figure 2, except that an ink prepared by mixing FR260C-1 (manufactured by Asahi Chemical Co.) ink and a fluorine-based surfactant (F-571) in a weight ratio of 100:0.05 (FR260C-1:F-571) was used. The FR260C-1 contains 25 to 35% by weight of polyester binder, so the weight ratio of the surfactant to 100 parts by weight of the binder is about 0.14 to 0.2 parts by weight.

[0110] Comparative Example 4. Screen printing was performed in the same manner as in Example 1 to produce the structure shown in Figure 2, except that an ink prepared by mixing FR260C-1 (manufactured by Asahi Chemical Co.) ink and a fluorine-based surfactant (F-571) in a weight ratio of 100:1 (FR260C-1:F-571) was used. Since the FR260C-1 contains 25 to 35% by weight of polyester binder, the weight ratio of the surfactant to 100 parts by weight of the binder is about 2.9 to 4 parts by weight.

[0111] Comparative Example 5. Screen printing was carried out in the same manner as in Example 2 using only FR260C-1 (Asahi Chemical) ink without mixing any fluorine-based surfactant, to manufacture a structure as shown in FIG.

[0112] Comparative Example 6. Screen printing was performed in the same manner as in Example 2 to produce the structure shown in Figure 2, except that an ink prepared by mixing FR260C-1 (manufactured by Asahi Chemical Co.) ink and a fluorine-based surfactant (F-571) in a weight ratio of 100:0.01 (FR260C-1:F-571) was used. Since the FR260C-1 contains 25 to 35% by weight of polyester binder, the weight ratio of the surfactant to 100 parts by weight of the binder is about 0.029 to 0.04 parts by weight.

[0113] Comparative Example 7. Screen printing was performed in the same manner as in Example 2 to produce the structure shown in Figure 2, except that an ink prepared by mixing FR260C-1 (manufactured by Asahi Chemical Co.) ink and a fluorine-based surfactant (F-571) in a weight ratio of 100:0.05 (FR260C-1:F-571) was used. Since the FR260C-1 contains 25 to 35% by weight of polyester binder, the weight ratio of the surfactant to 100 parts by weight of the binder is about 0.14 to 0.2 parts by weight.

[0114] Comparative Example 8. Screen printing was performed in the same manner as in Example 2 to produce the structure shown in Figure 2, except that an ink prepared by mixing FR260C-1 (manufactured by Asahi Chemical Co.) ink and a fluorine-based surfactant (F-571) in a weight ratio of 100:1 (FR260C-1:F-571) was used. Since the FR260C-1 contains 25 to 35% by weight of polyester binder, the weight ratio of the surfactant to 100 parts by weight of the binder is about 2.9 to 4 parts by weight.

[0115] The results of the above-mentioned Examples and Comparative Examples are summarized and shown in Tables 1 to 3 below.

[0116] [Table 1]

[0117] [Table 2]

[0118] [Table 3]

[0119] As summarized in Tables 1 to 3, in the case of the examples, the bezel pattern had thickness uniformity, was free of edge top defects, and was stably printed with excellent straightness, whereas in the case of the comparative examples, thickness uniformity, edge top characteristics, and straightness were not all ensured, or at least one of them was defective.

[0120] Test example 1. Folding durability evaluation The polymer film having the bezel printing pattern screen-printed according to Example 1 was subjected to a folding test. Figure 6 is an optical microscope photograph of the printing pattern after the folding test, from which it can be seen that the printing pattern is stably maintained without damage even after folding. In Figure 6, reference numeral 3000 denotes a printing area where a printing pattern exists, and reference numeral 4000 denotes an unprinted area where no printing pattern exists. [Explanation of symbols]

[0121] 100: Cover board 200: Adhesive layer or adhesive layer 300: Printing pattern 400: Substrate

Claims

1. A substrate; and a printed pattern formed on the substrate, the printed pattern includes one or more printed lines; the printing line comprises a polymeric binder, a colorant, and a fluorosurfactant; the colorant is a black pigment and / or dye; The printed line has a thickness uniformity of 0.6 μm or less and an edge-top deviation of 0.55 μm or less; The printing line includes a polymer binder in an amount of 50 to 95% by weight, a colorant in an amount of 20 to 90 parts by weight based on 100 parts by weight of the polymer binder, and a fluorine-based surfactant in an amount of 0.35 to 2.5 parts by weight based on 100 parts by weight of the polymer binder.

2. The printed substrate of claim 1, wherein the printed lines have a thickness in the range of 0.5 μm to 10 μm.

3. 2. The printed circuit board according to claim 1, wherein the printed lines have a straightness of 50 μm or less.

4. The printed circuit board according to claim 1 , wherein the printed pattern is a bezel pattern.

5. The composition includes a polymeric binder, a colorant, and a fluorosurfactant. the colorant is a black pigment and / or dye; The polymer binder is contained in an amount of 20 to 40% by weight, The colorant is included in an amount of 20 to 90 parts by weight based on 100 parts by weight of the polymer binder, The fluorosurfactant is contained in an amount of 0.35 to 2.5 parts by weight based on 100 parts by weight of the polymer binder.

6. 6. The screen printing ink according to claim 5, wherein the polymer binder is at least one selected from the group consisting of polyester, urethane-modified polyester, epoxy-modified polyester, acrylic-modified polyester, vinyl chloride-vinyl acetate copolymer resin, butyral resin, polyether urethane resin, polyester urethane resin, polycarbonate urethane resin, epoxy resin, phenol resin, acrylic resin, polyamide resin, polyamideimide resin, polyolefin resin, chlorinated polyolefin resin, chlorinated rubber, melamine resin, urea resin, ethyl cellulose resin, nitrocellulose resin, cellulose acetate butyrate, cellulose acetate propionate, rosin resin, maleic acid resin, natural resin, and alkyd resin.

7. 6. The screen printing ink according to claim 5, wherein the fluorosurfactant is a non-ionic surfactant.

8. 6. The screen printing ink according to claim 5, further comprising 20 to 90 parts by weight of a pigment or dye per 100 parts by weight of the polymer binder.

9. The screen printing ink according to claim 5, further comprising 100 to 300 parts by weight of a compound represented by the following formula 1, based on 100 parts by weight of the polymer binder: 【Chemistry 1】 In Chemical Formula 1, R １ is a hydrogen atom, an alkyl group or an alkylcarbonyl group, and L １ is an alkylene group, R ２ is an alkyl group or a hydrogen atom, and n is a number in the range of 1 to 10.

10. 10. The screen printing ink according to claim 9, wherein the proportion of the compound of formula 1 is less than 70% by weight.

11. 6. A method of screen printing comprising the step of transferring the screen printing ink according to claim 5 onto a substrate to be printed through a screen printing plate.

12. The screen printing method according to claim 11, wherein the printing speed is controlled to be in the range of 20 to 200 mm / sec.

13. The screen printing method according to claim 11, wherein the printing speed is controlled so that the S value of the following formula 1 falls within a range of 25 to 110: [Formula 1] S = R x W In Equation 1, R is the printing speed, and W is the parts by weight of surfactant per 100 parts by weight of polymer binder in the ink.

14. The screen printing method according to claim 11, further comprising forming a bezel pattern on a substrate to be printed.

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