JP2010153698A - Transparent conductive sheet, method of manufacturing the same, and decorative molded product - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a transparent conductive sheet having translucency and resistance to corrosion and not limiting the kind of metals constituting a metal thin film layer, and provide a method of manufacturing the same and a decorative molded product. <P>SOLUTION: A metal thin film sheet is at least formed in such manners as to allow a metal thin film layer 2 and a resist layer 3 to make contact with each other on a substrate sheet 1 and allow the resist layer 3 to be the front surface. In the resist layer 3 of the metal thin film sheet, many fine recesses 8 are formed in a part or the whole of the resist layer 3 by using a nano-imprint method. Then, the resist layers 10 existing on the bottom faces of the many fine recesses 8 that are formed are removed by dry etching, and the metal thin film layer 2 is exposed to the bottom faces of the many fine recesses 8 that are formed. Then, the metal thin film layer 2 that is exposed to the bottom faces of the many fine recesses 8 is removed by wet etching. Thereby, the whole or a part of the resist layer 3 and the metal thin film layer 2 are configured to form a fine mesh-like shape. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a transparent conductive sheet having transparency and electromagnetic shielding properties and conductivity, a manufacturing method thereof, and a decorative molded product manufactured using the transparent conductive sheet.

  In communication devices such as mobile phones, electronic information devices, liquid crystal displays, solar cells, and the like, a transparent conductive sheet excellent in transparency and conductivity is required.

  As this transparent conductive sheet, a transparent base sheet, a transparent conductive thin film layer provided on the transparent base sheet, and a transparent conductive film layer are provided on the basis of copper, and the line width is 15 μm, Some include a copper pattern layer having a square or rectangular lattice pattern with an aperture ratio of 70 to 90% and a colored layer formed on the copper pattern layer and made of copper oxide or copper sulfide.

  As a method for producing this transparent conductive sheet, a first step of providing a hydrophilic resin layer composed of polyhydroxyethyl acrylate or the like on one side of a transparent substrate sheet 1 and electroless plating on the hydrophilic resin layer A second step of providing a layer, a third step of treating the electroless plating layer with a copper electroless plating solution to form a copper thin film layer, and further performing copper plating by electrolysis on the hydrophilic resin layer, Some include at least a fourth step of providing a copper film layer of 1 to 10 μm on the entire surface and a fifth step of forming a grid-like copper pattern by photoetching the copper film layer using a masking film (for example, a patent Reference 1).

JP-A-11-330772

  However, the transparent conductive sheet produced by this manufacturing method is a very expensive facility in terms of the lack of transparency and the method of forming a grid-like copper pattern by performing photoetching using a masking film. There is a problem that the productivity of the transparent conductive sheet is greatly reduced, and there is a problem that the types of metals that can be used are limited.

  Accordingly, the present invention provides a transparent conductive sheet, a method for producing the same, and a transparent conductive decorative molded article that eliminates the above-mentioned problems and has transparency, and has conductivity and stable electromagnetic wave shielding properties. For the purpose. In order to achieve the above object, the transparent conductive sheet, the production method thereof, and the decorative molded product of the present invention are configured as follows.

  According to a first aspect of the present invention, in the method for producing a transparent conductive sheet, a base sheet, a metal thin film layer formed on the base sheet, and a resist formed on the metal thin film layer in contact with the metal thin film layer A first step of forming a fine recess in the resist layer of the metal thin film sheet using a nanoimprint method on the metal thin film sheet comprising at least a layer, and dry etching only the resist layer remaining on the bottom surface of the fine recess At least a second step of exposing the metal thin film layer to the bottom surface of the fine recess, and a third step of removing the exposed metal thin film layer by wet etching, so that the resist layer and the metal The thin film layer is configured to be formed in a fine mesh shape.

  According to a second aspect of the present invention, in the configuration of the first aspect of the present invention, the metal thin film layer is formed of any one of aluminum, nickel, gold, copper, silver, titanium, and zinc.

  According to a third aspect of the present invention, in the configuration of the first to second aspects of the present invention, the thickness of the metal thin film layer is 0.01 μm to 30 μm.

  According to a fourth aspect of the present invention, in the configuration of the first to third aspects of the invention, the line width of the mesh pattern of each fine mesh-shaped portion in the metal thin film layer is 0.01 μm to 2 μm. It is configured.

  According to a fifth aspect of the present invention, in the configuration of the first to fourth aspects of the present invention, the distance between lines of the mesh pattern of each fine mesh-shaped portion in the metal thin film layer is 5 of the line width of the mesh pattern. It is comprised so that it may be 2 times or more and less than 1000 times.

  According to the sixth aspect of the present invention, a metal thin film layer having a fine mesh shape is formed on a part or the entire surface of the substrate sheet, and at least the resist layer coincides with the mesh shape of the metal thin film layer. It is configured so as to be formed on the surface in a simple shape.

  The invention described in claim 7 is the structure of the invention described in claim 6, wherein the metal thin film layer is made of aluminum, nickel, gold, copper, silver, titanium, and zinc.

  According to an eighth aspect of the present invention, in the configuration of the sixth to seventh aspects of the invention, the line width of the mesh pattern of each fine mesh-shaped portion in the metal thin film layer is 0.01 μm to 2 μm. It is configured.

  According to a ninth aspect of the present invention, in the configuration of the sixth to eighth aspects of the present invention, the distance between lines of the mesh pattern of each fine mesh-shaped portion in the metal thin film layer is 5 of the line width of the mesh pattern. It is comprised so that it may be 2 times or more and less than 1000 times.

  The method for producing a transparent conductive sheet according to the present invention includes a base sheet, a metal thin film layer formed on the base sheet, and a metal thin film layer on the metal thin film layer so as to be in contact with the base sheet. A first step of forming a fine recess in the resist layer of the metal thin film sheet by using a nanoimprint method on the metal thin film sheet comprising at least a resist layer formed on the resist layer, and remaining on a bottom surface of the fine recess By including at least a second step of removing only the resist layer by dry etching and exposing the metal thin film layer to the bottom surface of the fine recess, and a third step of removing the exposed metal thin film layer by wet etching, Since the resist layer and the metal thin film layer are formed in a fine mesh shape, stable electromagnetic wave shielding, translucency and anticorrosion Have sex, and in which an expensive transparent conductive sheet can be freely selected a metal constituting the metal thin film layer 2 to maintain high productivity without the need for equipment can be easily obtained.

  Embodiments according to the present invention will be described below in more detail with reference to the drawings. It should be noted that the dimensions, materials, shapes, relative positions, etc. of the members and parts described in the embodiments of the present invention are not intended to limit the scope of the present invention only to those unless otherwise specified. It is merely an illustrative example.

  First, the detail of the metal thin film sheet used for this invention is demonstrated.

  1A is a cross-sectional view of a metal thin film sheet 100 used in the manufacturing method of the present invention, and FIG. 1B is a cross-sectional view of a modification of the metal thin film sheet 100 used in the manufacturing method of the present invention. . 1A, a metal thin film sheet 100 includes a base sheet 1, a metal thin film layer 2 formed on the base sheet 1, and a metal thin film layer 2 in contact with the metal thin film layer 2. And a resist layer 3 formed thereon. Below, each component of this metal thin film sheet 100 is demonstrated.

  The base sheet 1 is for supporting the metal thin film layer 2, the resist layer 3 and the like on the sheet, and is made of a transparent synthetic resin or the like. It does not specifically limit as a material of the base sheet 1, The thing which has mold release property and the thing which has adhesiveness can be used. As the material of the base sheet 1 having releasability, a resin sheet such as polypropylene resin, polyethylene resin, polyamide resin, polyester resin, acrylic resin, polyvinyl chloride resin, aluminum foil, copper foil Metal foils such as glassine paper, coated paper, cellophane and other cellulose-based sheets, or composites of the above-mentioned respective sheets. As a material when the base sheet 1 has adhesiveness, a thermoplastic resin sheet such as a polypropylene resin, a polyethylene resin, a polyamide resin, a polyester resin, an acrylic resin, a polyvinyl chloride resin, or a polyurethane resin And thermosetting sheets such as epoxy resins and polyimide resins, other transparent members such as glass plates, and composites of the above-described respective sheets.

  The metal thin film layer 2 is for expressing transparency, and is formed on the base sheet 1. As the material of the metal thin film layer 2, depending on the transparent color to be expressed, a metal such as aluminum, tin, nickel, gold, platinum, chromium, iron, copper, indium, silver, titanium, lead, zinc, or an alloy thereof A compound etc. can be mentioned. Examples of the method for forming the metal thin film layer 2 include a vacuum deposition method, a sputtering method, an ion plating method, and a plating method.

  The resist layer 3 is formed on the metal thin film layer 2 so as to be in contact with the metal thin film layer 2. Examples of the material of the resist layer 3 include vinyl resins, epoxy resins, amide resins, polyester resins, acrylic resins, polyurethane resins, polyvinyl acetal resins, polyester urethane resins, cellulose ester resins, alkyd resins, and the like. Examples thereof include an ink containing a resin as a binder and appropriately containing additives such as extender pigments and colorants such as pigments or dyes. Furthermore, FOX (registered trademark) -12 FLOWABLE OXIDE, FOX (registered trademark) -14 FLOWABLE OXIDE, FOX (registered trademark) -15 FLOWABLE OXIDE, FOX (registered trademark) -16 FLOWABLE OXIDE, manufactured by Toray Dow Corning Co., Ltd. A sol-gel material such as a mixture of these can also be used. As a method for forming the resist layer 3, in addition to a normal printing method such as an offset printing method, a gravure printing method, or a screen printing method, a coating method such as a gravure coating method, a roll coating method, a comma coating method, or a lip coating method is adopted. can do.

  If necessary, the release layer 4 may be formed between the base sheet 1 and the metal thin film layer 2. The release layer 4 is a layer that is released from the metal thin film layer 2 together with the base sheet 1 when the base sheet 1 is peeled off after transfer. As the material of the release layer 4, melamine resin release agent, silicone resin release agent, fluororesin release agent, cellulose derivative release agent, urea resin release agent, polyolefin resin release agent , Paraffin type release agents and composite release agents thereof. Examples of the method for forming the release layer 4 include coating methods such as a roll coating method and a spray coating method, and printing methods such as a gravure printing method and a screen printing method.

  The peeling layer 5 may be arrange | positioned between the mold release layer 4 and the metal thin film layer 2 as needed. The release layer 5 is a layer that is peeled off from the base sheet 1 or the release layer 4 and disposed on the outermost surface of the transfer object when the base sheet 1 is peeled after transfer or after simultaneous molding. The release layer 5 may be made of acrylic resin, polyester resin, polyvinyl chloride resin, cellulose resin, rubber resin, polyurethane resin, polyvinyl acetate resin, or vinyl chloride-vinyl acetate copolymer. Examples thereof include copolymers such as system resins and ethylene-vinyl acetate copolymer resins. When the release layer 5 requires hardness, a photo-curing resin such as an ultraviolet curable resin, a radiation curable resin such as an electron beam curable resin, or a thermosetting resin may be selected and used. The release layer 5 may be colored or uncolored. Examples of the method for forming the release layer 5 include a coating method such as a gravure coating method, a roll coating method, and a comma coating method, and a printing method such as a gravure printing method and a screen printing method.

  The pattern layer 6 may be formed between the peeling layer 5 and the metal thin film layer 2 as needed.

  With reference to FIG. 1B, a design layer 6 may be further formed on the base sheet 1 independently of the metal thin film layer 2 and the resist layer 3.

  The pattern layer 6 is a layer having decorative functions such as various patterns and characters in addition to the transparent pattern formed by the metal thin film layer 2. As a material of the pattern layer 6, a binder such as a polyvinyl resin, a polyamide resin, a polyester resin, an acrylic resin, a polyurethane resin, a polyvinyl acetal resin, a polyester urethane resin, a cellulose ester resin, or an alkyd resin is used as a binder. And a color ink containing an appropriate color pigment or dye as a colorant. Examples of the method for forming the pattern layer 6 include a normal printing method such as a gravure printing method, a screen printing method, and an offset printing method. In particular, the offset printing method and the gravure printing method are suitable for performing multicolor printing and gradation expression. In the case of a single color, a coating method such as a gravure coating method, a roll coating method, or a comma coating method may be employed.

  The anchor layer 7 may be formed between the metal thin film layer 2 and the base sheet 1 as necessary. The anchor layer 7 is a layer for improving the adhesion of the metal thin film layer 2 to the base sheet 1. As the material of the anchor layer 7, two-component cured urethane resin, thermosetting urethane resin, melamine resin, cellulose ester resin, chlorine-containing rubber resin, chlorine-containing vinyl resin, acrylic resin, epoxy resin, vinyl Based copolymer resins and the like. Examples of a method for forming the anchor layer 7 include a coating method such as a gravure coating method, a roll coating method, and a comma coating method, a printing method such as a gravure printing method, and a screen printing method.

  Next, the manufacturing method of the transparent conductive sheet 110 of this invention is demonstrated.

  FIG. 2 is a diagram showing a schematic process of the method for manufacturing the transparent conductive sheet 110 of the present invention. FIG. 2A is a cross-sectional view when the metal thin film sheet 100 and the stamper S used in the first step of the manufacturing method according to the present invention are integrated. FIG. 2B is a cross-sectional view of the metal thin film sheet 100 after the fine recesses 8 are formed in the resist layer 3 in the first step of the manufacturing method according to the present invention. FIG. 2C is a cross-sectional view of the metal thin film sheet 100 when the remaining resist layer 10 present on the bottom surface of the fine recess 8 is removed in the second step of the manufacturing method according to the present invention. FIG.2 (d) is sectional drawing of the metal thin film sheet 100 when removing the metal thin film layer 2 which exists in the bottom face of the fine recessed part 8 at the 3rd process of the manufacturing method concerning this invention.

  Referring to FIG. 2 (a), in the first step of the present invention, a fine concave portion 8 and a fine convex portion 9 having a mesh shape are formed on a part or the entire surface of the resist layer 3 of the metal thin film sheet 100 using a nanoimprint method. Is formed. And after the fine recessed part 8 and the mesh-shaped fine convex part 9 are formed in the resist layer 3 of the metal thin film sheet 100, it transfers to the 2nd process of this invention.

  The nanoimprint method is a processing method in which a stamper S provided with fine convex portions is pressed against the resist layer 3 to form fine concave portions 8 and mesh-shaped fine convex portions 9 on the resist layer 3. Typical examples of the nanoimprint method include a thermal nanoimprint method, an optical nanoimprint method, and a room temperature nanoimprint method. Below, the method of forming the fine recessed part 8 and the fine convex part 9 of a mesh shape in the resist layer 3 using each of the thermal nanoimprint method, the optical nanoimprint method, and the room temperature nanoimprint method is demonstrated.

  In the case where the fine concave portions 8 and the fine mesh-shaped convex portions 9 are formed on the resist layer 3 using the thermal nanoimprint method, the resin layer 3 of the metal thin film sheet 100 has a vinyl resin, an amide resin, or a polyester resin. , Acrylic resin, polyurethane resin, polyvinyl acetal resin, polyester urethane resin, cellulose ester resin, alkyd resin, etc. as binder, and appropriately contain additives such as extender pigments and colorants such as pigments or dyes It is recommended to use ink to be used. In order to form fine concave portions 8 and fine mesh-shaped convex portions 9 in the resist layer 3 using the thermal nanoimprint method, first, a stamper S made of nickel electroforming is used from a mother die drawn with an electron beam or the like. Make it. Next, it is placed on the resist layer 3, pressed under high temperature and high pressure, then cooled, and the stamper S is removed from the resist layer 3, thereby forming a fine recess 8 in the resist layer 3. The temperature of the stamper S at the time of pressing may be higher than the softening point of the resist layer 3 and lower than the thermal decomposition temperature. The pressure applied to the metal thin film sheet 100 at the time of pressing is usually preferably set in the range of several MPa to several tens of MPa. Under the above conditions, the stamper S is pressed against the resist layer 3 for several seconds to several minutes, rapidly cooled or naturally cooled, and allowed to stand until the surface of the resist layer 3 is below the softening point, Fine concave portions 8 and mesh-shaped fine convex portions 9 can be formed in the resist layer 3.

  When forming the fine recessed part 8 and the fine mesh-shaped convex part 9 in the resist layer 3 using the optical nanoimprint method, the resist layer 3 of the metal thin film sheet 100 is made of an acrylic resin, a urethane resin, an epoxy resin, or the like. A photo-curing resin may be used. In order to form the fine concave portions 8 and the fine mesh-shaped convex portions 9 in the resist layer 3 using the optical nanoimprint method, first, a transparent stamper S that can transmit ultraviolet light such as quartz is prepared. The stamper S is placed on the resist layer 3 using a photo-curing resin that is cured by ultraviolet light, pressed, and then cured by irradiating with ultraviolet light, and the stamper S is removed from the resist layer 3 to form a resist layer 3. A minute recess 5 may be formed. The optical nanoimprint method does not require a high temperature for pressing, and can be performed at a pressure of several MPa or less, so that the dimensional change is small, and since the stamper S is transparent, the stamper S passes through the stamper S and the stamper S. There is an advantage that it can be easily aligned.

  In the case where fine concave portions 8 and fine mesh-shaped convex portions 9 are formed in the resist layer 3 by using the room temperature nanoimprint method, the resist layer 3 of the metal thin film sheet 100 has a sol-gel material such as Toray Dow Corning Co., Ltd. FOX (registered trademark) -12 FLOWABLE OXIDE, FOX (registered trademark) -14 FLOWABLE OXIDE, FOX (registered trademark) -15 FLOWABLE OXIDE, FOX (registered trademark) -16 FLOWABLE OXIDE, and a mixture thereof are used. Can do. In order to form fine concave portions 8 and fine mesh-shaped convex portions 9 in the resist layer 3 by using room temperature nanoimprint, it is only necessary to press the stamper S against the resist layer 3 at room temperature. By pressing the stamper S against the resist layer 3 while maintaining the room temperature, the minute recesses 5 can be formed in the resist layer 3. The pressure at the time of pressing is generally preferably set to several MPa to several tens of MPa. The room temperature nanoprinting method has an advantage that a cooling step is not required as compared with other methods.

  The widths of the fine mesh-shaped protrusions 9 formed on all or part of the resist layer 3 by various methods of nanoimprinting are preferably formed to be in the range of 0.01 μm to 2 μm, respectively. More preferably, it is the range of 0.05 micrometer-0.5 micrometer. Within this range, the fine mesh-shaped convex portions 9 are formed on all or a part of the resist layer 3, whereby the transparent conductive sheet 110 having high transparency and radio wave shielding can be produced. Because. That is, when the width of the fine convex portion 9 in the mesh shape exceeds 2 μm, there arises a problem that the mesh shape becomes visible, whereas the width of the fine convex portion 9 in the mesh shape is less than 0.01 μm. This is because there arises a problem that the electromagnetic wave shielding property of the transparent conductive sheet 110 produced in the present invention is lowered.

  Referring to FIG. 2B, in the second step of the present invention, the remaining resist layer 10 existing on the bottom surface portion of the fine recess 8 formed in the resist layer 3 is removed to form the resist layer 3. The metal thin film layer 2 is completely exposed on the bottom surface of the fine recess 8 formed. After the metal thin film layer 2 is completely exposed on the bottom surface of the fine recess 8, the process proceeds to the next step.

  In the second step, the remaining resist layer 10 existing on the bottom surface of the fine recess 8 formed in the resist layer 3 is completely removed. Examples of the method for removing the remaining resist layer 10 include a dry etching method and a wet etching method.

  The dry etching method is a method of etching a material with a reactive gas, ions, or radicals. The dry etching method includes reactive gas etching that exposes the material to the reactive gas, reactive ion etching that ionizes and radicalizes the gas with plasma, ion beam etching that etches the target with inert ions as a beam, Reactive ion beam etching that etches a target with chemically active ions in the form of a beam, irradiation of a solid material with a strong laser beam, and various elements (atoms, molecules, radicals, clusters, liquids) There is reactive laser beam etching that explosively releases the droplets and their ions, etc., and etches the target surface. However, the residual resist layer 10 existing on the bottom surface of the fine recess 8 is removed by any method. May be. In particular, in the case of reactive ion etching, a fluorine-based gas such as sulfur hexafluoride, carbon tetrafluoride, or trifluoromethane is used as an etching gas. In the case of reactive gas etching, xenon difluoride is used as an etching gas. The remaining resist layer 10 present on the bottom surface of the recess 8 may be removed.

  The wet etching method is a method of etching a metal with a solution having high reactivity with the metal. In the wet etching method, a metal thin film sheet 100 is immersed in a container filled with a metal etching solution, and a dip type that erodes the exposed metal thin film layer 2. There are a spray type sprayed on 100 and a spin type in which a metal thin film sheet 100 is attached to a turntable called a spinner and a metal etching solution is dropped, but any method is used to protect the metal thin film layer not protected by the resist layer 3 Two sites may be removed. Of these methods, the dip method is more preferable because it can be most easily performed. As the metal etching solution, a weakly acidic or weakly alkaline aqueous solution is used, and the concentration, immersion temperature, and immersion time of the metal etching solution may be appropriately selected depending on the material and thickness of the metal thin film layer 2.

  In order to completely remove the remaining resist layer 10 existing on the bottom surface of the fine recess 8, anisotropic etching is required, and therefore dry etching is more preferable. In addition, the dry etching method is preferable in that it can be easily performed because there is no post-processing step unlike the wet etching method.

  Referring to FIG. 2C, in the third step of the present invention, the metal thin film layer 2 exposed on the bottom surface of the fine recess 8 is removed from the metal thin film sheet 100 by wet etching.

  Referring to FIG. 2D, the resist layer 3 and the metal thin film layer 2 have a fine mesh shape through the first to third steps, and have transparency and radio wave shielding. A transparent conductive sheet 110 can be obtained.

  In addition, it is preferable that the thickness of the metal thin film layer 2 of the metal thin film sheet 100 used by this invention is 0.01-30 micrometers. That is, when the thickness of the metal thin film layer 2 is less than 0.01 μm, the transparency of the metal thin film layer 2 is lowered and the transparency of the transparent conductive sheet 110 to be produced is lowered, whereas it exceeds 30 μm. In the second step of the present invention, it takes time for the metal thin film layer 2 to be dry-etched, and the productivity of the transparent conductive sheet 110 is reduced.

  Furthermore, the film thickness of the resist layer 3 of the metal thin film sheet 100 is preferably 0.1 to 10 μm. That is, when the thickness of the resist layer 3 is less than 0.1 μm, the chemical resistance is insufficient. Therefore, in the third step of the present invention, the metal thin film layer 2 formed in a portion other than the fine concave portion 8 in the metal thin film sheet 100. This is because the problem that etching is likely to occur occurs, whereas when the thickness of the resist layer 3 exceeds 10 μm, the productivity in producing the transparent conductive sheet 110 decreases.

  Next, details of the transparent conductive sheet 110 obtained by the manufacturing method of the present invention will be described. In addition, about the component of the transparent conductive sheet 110, since it is the same as that of the component demonstrated in the metal thin film sheet 100 about the same component as the metal thin film sheet 100, it abbreviate | omits here.

  FIG. 3A is a plan view of the transparent conductive sheet 110 of the present invention, and FIG. 3B is a cross-sectional view taken along the line III-III in FIG. FIG. 4A is an enlarged view of the α portion in FIG. FIG. 4B is an enlarged view of a modified example of the portion α in FIG.

  Referring to FIG. 3B, the first embodiment of the transparent conductive sheet 110 of the present invention basically includes a base sheet 1, a metal thin film layer 2 having a fine mesh shape, and a metal thin film layer. 2 and a resist layer 3 formed on the metal thin film layer 2 in a shape that matches the fine mesh shape of 2, a release layer 4, a release layer 5, and a design layer 6, as necessary. An adhesive layer 11 is provided.

  The fine mesh shape formed on the metal thin film layer 2 and the resist layer 3 is composed of fine concave portions 8 and fine convex portions 9 having a mesh shape, and is formed over the entire surface of the transparent conductive sheet 110. Yes.

  4 (a) and 4 (b), among the fine concave portions 8 and the fine convex portions 9 constituting the fine mesh shape, the fine concave portions 8 have a linear shape, The mesh-shaped fine convex portion 9 has a polygonal shape, a circular shape, or a shape obtained by combining these.

Referring to FIG. 3B again, it is preferable that the line width W of the fine convex portion 9 of the mesh shape constituting the fine mesh shape is in the range of 0.01 μm to 2 μm. Further, the relationship between the line width W of the fine mesh-shaped convex portion 9 and the inter-line distance L of the fine mesh-shaped convex portion 9 is the mesh shape with respect to the line width W of the fine mesh-shaped convex portion 9. It is preferable that the ratio of the line-to-line distance L of the fine protrusions 9 (hereinafter referred to as the line-to-line ratio X) is within the range represented by (Formula 1).
(Formula 1): 5 ≦ X (= L / W) ≦ 1000
If the line width W and the line spacing ratio X are in this range, a transparent conductive sheet 110 having high transparency and conductivity can be obtained. That is, when the mesh pattern line width W exceeds 2 μm or the mesh pattern line ratio X is less than 5, the problem arises that the translucency of the transparent conductive sheet 110 is reduced, whereas the mesh pattern When the line width W is less than 0.01 μm or the mesh pattern line-to-line ratio X exceeds 1000, the conductivity of the metal thin film sheet 100 is lowered, and it becomes difficult to have electromagnetic wave shielding properties. The width W and the line-to-line ratio X are preferably in the above range. Further, even if the metal thin film layer 2 is formed of a material exhibiting a colored metallic luster, such as a brown-colored copper thin film or a silver-white silver thin film, the line width W and the line-to-line ratio X are If it is within the range, it is a level that cannot be normally confirmed by visual observation, so that it appears as if it is a colorless and transparent layer, so that the transparent conductive sheet 110 having the same effect can be formed.

  Furthermore, as a result of configuring the metal thin film layer 2 and the resist layer 3 in this way, the metal thin film layer 2 that has conventionally served only as a metal-like conductive circuit can also serve as a transparent conductive film, If connected to an external printed circuit board, it can be used for applications such as a transparent touch switch and a transparent antenna.

  As needed, you may form the contact bonding layer 11 on the fine convex part 9 of a mesh shape completely or partially. The adhesive layer 11 adheres each of the above layers to the surface to be decorated. Further, the adhesive layer 11 is formed in a portion to be bonded. That is, when the part to be bonded is entirely, the adhesive layer 11 is formed on the entire surface. If the part to be bonded is partial, the adhesive layer 11 is partially formed. As the adhesive layer 11, a heat-sensitive or pressure-sensitive resin suitable for the material to be decorated is used as appropriate. For example, when the material to be decorated is an acrylic resin, an acrylic resin may be used. If the material to be decorated is polyphenylene oxide / polystyrene resin, polycarbonate resin, styrene copolymer resin, or polystyrene blend resin, acrylic resin, polystyrene resin, polyamide having affinity with these resins A series resin or the like may be used. Furthermore, when the material to be decorated is a polypropylene resin, chlorinated polyolefin resin, chlorinated ethylene-vinyl acetate copolymer resin, cyclized rubber, and coumarone indene resin can be used. Examples of the method for forming the adhesive layer 11 include a coating method such as a gravure coating method, a roll coating method, and a comma coating method, a printing method such as a gravure printing method, and a screen printing method.

  FIG. 5A is a plan view of the transparent conductive sheet 110 according to the second embodiment of the present invention. FIG.5 (b) is sectional drawing in the III-III line of the transparent conductive sheet 110 shown in Fig.5 (a). Since the basic configuration of the transparent conductive sheet 110 according to this embodiment is the same as that according to the first embodiment, only the differences will be described here.

  Referring to FIG. 5A, the transparent conductive sheet 110 of the second embodiment of the present invention is fine only for a part of the metal thin film layer 2 and the resist layer 3 constituting the transparent conductive sheet 110. A concave portion 8 and a fine convex portion 9 having a mesh shape. A fine mesh shape is formed. As a result, since this transparent conductive sheet 110 is a transparent conductive film that is completely different from the solid design of the metal thin film layer 2 in appearance, there is no portion where the solid design of the metal thin film layer 2 is not formed. Despite being visible, it is possible to form a transparent conductive film 110 with a transparent conductive portion having a function of conductivity and electromagnetic wave shielding that is the same as the solid design portion of the metal thin film layer 2 in terms of electrical performance. .

  Finally, the manufacturing method for decorating the molded resin using the transparent conductive sheet 110 of the present invention to obtain a decorated molded product will be described.

  FIG. 6 is a cross-sectional view showing a schematic process in the manufacturing method of the present invention. FIG. 6A is a cross-sectional view when the transparent conductive sheet 110 is installed in a mold. FIG. 6B is a cross-sectional view when resin is injected into a mold in which the transparent conductive sheet 110 is installed. FIG.6 (c) is sectional drawing when taking out the decorative molded product in which resin and the transparent conductive sheet 110 were integrated from the inside of a metal mold | die.

  With reference to FIG. 6A, in the first step in the present invention, the transparent conductive sheet 110 is fed into a molding die 14 composed of a movable mold 12 and a fixed mold 13. In that case, the transparent conductive sheet 110 of a sheet | seat may be sent one by one, and the required part of the elongate transparent conductive sheet 110 may be sent intermittently. When using the long transparent conductive sheet 110, it is preferable to use a feeding device having a positioning mechanism so that the pattern of the transparent conductive sheet 110 and the register of the molding die 14 coincide. Further, when the transparent conductive sheet 110 is intermittently fed, if the transparent conductive sheet 110 is fixed by the movable mold 12 and the fixed mold 13 after the position of the transparent conductive sheet 110 is detected by a sensor, This is convenient because the transparent conductive sheet 110 can be fixed at the same position at all times, and no pattern displacement occurs.

  Referring to FIG. 6B, in the second step of the present invention, after the molding die 14 is closed, the molten resin 15 is injected and filled into the molding die 14 from the gate to form a decoration. At the same time, the transparent conductive film sheet 110 is adhered to the surface.

  With reference to FIG.6 (c), in the 3rd process in this invention, after cooling the decorative molded product which is a to-be-decorated object, the metal mold | die 14 for molding is opened and a decorative molded product is taken out.

  In addition, when producing a decorative molded product using the transparent conductive sheet 110 composed of the base sheet 1 having releasability, in the third step, the decorative molded product is taken out from the mold and added. After the base sheet 1 is peeled from the decorative molded product or the decorative molded product is taken out from the mold, the base molded sheet 1 is peeled from the decorative molded product to obtain a transfer molded product.

  In addition, a method for decorating the surface of the transfer object using a method other than the above using the transparent conductive sheet 110 will be described.

  First, the adhesive layer 11 of the transparent conductive sheet 110 is adhered to the surface of the transfer object. Next, using a transfer machine such as a roll transfer machine or an up-down transfer machine equipped with a heat-resistant rubber-like elastic body such as silicon rubber, a heat-resistant rubber-like condition set at a temperature of about 80 to 260 ° C. and a pressure of about 490 to 1960 Pa. Heat and pressure are applied from the base sheet 1 side of the transparent conductive sheet 110 through the elastic body. By doing so, the adhesive layer 11 adheres to the surface of the transfer object. Finally, when the base sheet 1 is peeled off after cooling, peeling occurs at the boundary surface between the base sheet 1 and the release layer 5 and transfer is completed.

  As the material to be transferred, those made of various materials such as a resin molded product can be used. The transfer object may be transparent, translucent, or opaque. Further, the transfer object may be colored or not colored. Examples of the resin include general-purpose resins such as polystyrene resin, polyolefin resin, ABS resin, AS resin, and AN resin. Also, general engineering resins such as polyphenylene oxide / polystyrene resins, polycarbonate resins, polyacetal resins, acrylic resins, polycarbonate-modified polyphenylene ether resins, polybutylene terephthalate resins, ultrahigh molecular weight polyethylene resins, polysulfone resins, polyphenylene sulfide resins Super engineering resins such as polyphenylene oxide resins, polyarylate resins, polyetherimide resins, polyimide resins, liquid crystal polyester resins, and polyallyl heat-resistant resins can also be used. Furthermore, composite resins to which reinforcing materials such as glass fibers and inorganic fillers are added can also be used.

  The present invention will be described more specifically with reference to the following examples and comparative examples, but the present invention is not limited to these examples.

  After using a 38 μm-thick polyester resin film as the base sheet, a melamine resin release layer, an acrylic resin release layer, and a urethane resin anchor layer before metal deposition are sequentially formed on the base sheet by gravure printing. A metal vapor deposition layer made of aluminum having a thickness of 0.06 μm is formed by vacuum vapor deposition, a resist layer made of vinyl resin having a thickness of 0.2 μm is formed on a part of the metal vapor deposition layer by gravure printing, and a metal thin film A sheet was obtained. Next, with a nanoimprint mold made of nickel electroforming in which a square lattice pattern with a width of 0.1 μm and a pitch of 0.7 μm is formed in a concave shape with a thickness of 0.18 μm, the pressure is 5 MPa under a heating of 100 ° C. The mold was released by pressing, cooling with water and leaving for 5 minutes, and fine protrusions composed of the lattice pattern were formed on the resist layer surface.

  Thereafter, the remaining resist layer remaining in the fine recesses was removed by dry etching. Next, when immersed in a metal etching solution made of 0.2% potassium hydroxide aqueous solution for 2 seconds, only the portion where the resist layer is not formed on the metal thin film layer is removed, and a part of the metal thin film layer has a line width of 0.1 μm. Thus, a transparent conductive sheet formed into a fine shape composed of a square lattice pattern with a pitch of 0.7 μm was obtained. Next, an adhesive layer made of an acrylic resin was formed on the entire surface of the transparent conductive sheet by a reverse coating method. Finally, the transparent conductive sheet having the adhesive layer formed on the entire surface was transferred to the surface of the colorless and transparent acrylic resin molded product by a molding simultaneous transfer method to obtain a decorative molded product.

  The obtained decorative molded product was the same as the colorless and transparent acrylic molded product in appearance, but the metal thin film portion formed in a fine shape had sufficient electromagnetic wave shielding properties. As a result, the obtained decorative molded product was able to block harmful electromagnetic waves and protect electronic components from malfunctioning due to jamming radio waves. Further, by connecting a part of the metal thin film layer of the decorative molded product to the external electrode, it can be used as a transparent antenna.

  An acrylic resin film having a thickness of 100 μm is used as a base sheet, and after a vinyl resin pattern layer and a urethane resin anchor layer before metal deposition are formed on the base sheet by gravure printing, the thickness is reduced to 0 by electroless plating. A metal plating layer made of 1 μm copper was formed. Then, a resist layer made of acrylic resin having a thickness of 0.1 μm is formed on a part of the metal plating layer by gravure printing, and then a regular hexagonal honeycomb pattern having a width of 0.05 μm and a side of 0.4 μm is thick. A nanoimprint mold made of nickel electroforming formed into a concave shape with a thickness of 0.08 μm was pressed at a pressure of 10 MPa under a heating temperature of 120 ° C., cooled with water and left for 10 minutes. Protrusions made of the honeycomb pattern were formed on the layer surface.

  Next, after removing the remaining resist layer remaining in the minute recesses by dry etching, and immersing in a metal etching solution made of 0.3% iron chloride aqueous solution for 2 seconds, only the portion of the metal thin film layer where the resist layer was removed is removed. Thus, a transparent conductive sheet was obtained in which a part of the metal thin film layer was formed into a fine shape composed of a regular hexagonal honeycomb pattern with a side of 0.4 μm. Next, an adhesive layer made of vinyl resin was formed on the entire surface of the transparent conductive sheet by a gravure printing method. Finally, the transparent conductive sheet having the adhesive layer formed on the entire surface was adhered to the surface of the colorless and transparent acrylic resin molded product by a simultaneous molding insert method to obtain a decorative molded product.

  The obtained decorative molded product was the same as the colorless and transparent acrylic molded product in appearance, but the metal thin film portion formed in a fine shape had sufficient electromagnetic wave shielding properties. As a result, the obtained decorative molded product was able to block harmful electromagnetic waves and protect electronic components from malfunctioning due to jamming radio waves. Moreover, by connecting a part of the metal thin film layer of the decorative molded product to the external electrode, it was possible to function as a capacitance switch pattern.

  (Comparative Example 1 and Comparative Example 2) Comparative Example 1 and Comparative Example 1 were the same as Example 1 or Example 2 except that the metal thin film layers of Examples 1 and 2 were formed by the conventional sputtering method using tin oxide. Example 2 was performed. Further, Comparative Example 1 and Comparative Example 2 were carried out in the same manner as in Example 1 or Example 2 except that the convex portions of the lattice pattern of Example 1 or the honeycomb pattern of Example 2 were formed by conventional photolithography. did.

  In any of the above comparative examples, the conductivity was low and the electromagnetic wave shielding property was lacking. In addition, since the conductive resistance of tin oxide itself is high, the surface resistance value changes due to a slight thickness variation, and the conductivity and electromagnetic wave shielding properties vary depending on the production lot and each part of the product, and the transparent conductive sheet of the present invention The electrical characteristics were inferior compared to the molded product to which is attached.

  The present invention can be suitably used in various molded products such as communication devices such as mobile phones, electronic information devices, liquid crystal displays, and solar cells, and is industrially useful.

It is sectional drawing which shows one Example of a metal thin film sheet. It is sectional drawing which shows one Example of the manufacturing method which concerns on the transparent conductive sheet of this invention. It is the top view and sectional drawing which show one Example of the transparent conductive sheet of this invention. It is an enlarged view which shows one Example of the transparent conductive sheet of this invention. It is the top view and sectional drawing which show one Example of the transparent conductive sheet of this invention. It is sectional drawing which shows one Example which concerns on the manufacturing method of a decorative molded product.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Base sheet 2 Metal thin film layer 3 Resist layer 4 Release layer 5 Release layer 6 Design layer 7 Anchor layer 8 Fine concave part 9 Fine convex part 10 Residual resist layer 11 Adhesive layer 12 Movable type 13 Fixed type 14 Mold for molding 15 Molding resin 100 Metal thin film sheet 110 Transparent conductive sheet S Stamper W Line width L Line distance

Claims (9)

  In a method for producing a transparent conductive sheet, a metal thin film sheet comprising at least a base sheet, a metal thin film layer formed on the base sheet, and a resist layer in contact with the metal thin film layer and formed on the metal thin film layer In addition, the first step of forming a fine recess in the resist layer of the metal thin film sheet using the nanoimprint method, and removing only the resist layer remaining on the bottom surface of the fine recess by dry etching, By providing at least a second step of exposing the metal thin film layer on the bottom surface and a third step of removing the exposed metal thin film layer by wet etching, the resist layer and the metal thin film layer are formed in a fine mesh shape. A method for producing a transparent conductive sheet, comprising: forming a transparent conductive sheet.   The method for producing a transparent conductive sheet according to claim 1, wherein the metal thin film layer is made of any one of aluminum, nickel, gold, copper, silver, titanium, and zinc.   The method for producing a transparent conductive sheet according to claim 1, wherein the metal thin film layer has a thickness of 0.01 μm to 30 μm.   The method for producing a transparent conductive sheet according to any one of claims 1 to 3, wherein a line width of a mesh pattern of each fine mesh-shaped portion in the metal thin film layer is 0.01 µm to 2 µm.   The method according to any one of claims 1 to 4, wherein a distance between lines of the mesh pattern of each fine mesh-shaped portion in the metal thin film layer is not less than 5 times and less than 1000 times the line width of the mesh pattern. The manufacturing method of the transparent conductive sheet manufactured by (1).   A metal thin film layer having a fine mesh shape is formed on a part or the entire surface of the substrate sheet, and at least a resist layer is formed on the surface so as to coincide with the mesh shape of the metal thin film layer. A transparent conductive sheet characterized by that.   The transparent conductive sheet according to claim 6, wherein the metal thin film layer is made of aluminum, nickel, gold, copper, silver, titanium, or zinc.   The transparent conductive sheet according to any one of claims 6 to 7, wherein a line width of a mesh pattern of each fine mesh-shaped portion in the metal thin film layer is 0.01 µm to 2 µm.   The method according to any one of claims 6 to 8, wherein a distance between lines of the mesh pattern of each fine mesh-shaped portion in the metal thin film layer is not less than 5 times and less than 1000 times the line width of the mesh pattern. The produced transparent conductive sheet.

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