SURFACE MATERIAL, METAL NET AND MANUFACTURING METHOD FOR THEM

Abstract

Surface material (1), comprising: a resin layer (4) comprising a binder (2) and a plurality of polypyrrole particles (3); an electroless-generated coating film (7) provided on one main surface (4a) of the resin layer (4) and comprising several first electroless-generated coating films (5) and a second electroless-generated coating film (6); and a transparent base material (8) provided on the other main surface (4b) of the resin layer (4), wherein some polypyrrole particles (3) are exposed on one main surface (4a) of the resin layer (4), thereby forming exposed surfaces (3a) by the exposed polypyrrole particles (3) distributed on one main surface (4a) of the resin layer (4), the first electroless-generated coating films (5) being provided on one main surface (4a) of the resin layer (4),that these each enclose the exposed surfaces (3a) of the exposed polypyrrole particles (3), and the second electroless-generated coating film (6) is provided such that it covers the first electroless-generated coating films (5), wherein a main surface (6a) of the second electroless-generated coating film (6) facing the first electroless-generated coating films (5) forms concave sections (6r) which each extend along the surfaces of the first electroless-generated coating films (5).

Description

TECHNICAL AREA

[0001] The present invention relates to a sheet material, a metal mesh and a manufacturing process therefor. BACKGROUND

[0002] In recent years, attempts have been made to develop a metal mesh that is obtained by structuring a fine wire made of metal, e.g. copper or silver, into a mesh form, which is used as an electrode element for an electronic component, e.g. a touch panel.

[0003] The metal mesh offers advantages in terms of cost reduction and lower resistance compared to conventional transparent conductive films, such as ITO (indium tin oxide) film. However, if the metal mesh is used as an electrode element for a touch panel or similar device, its invisibility becomes more problematic than that of the ITO film.

[0004] A metal mesh with improved invisibility is known to consist of a copper layer and a blackening metal layer. For example, PTL 1 and PTL 2 disclose a metal mesh using a metal oxide or the like, whose corrosion rate is lower than that of copper, and a metal mesh using, for example, a zinc layer as the blackening metal layer.

[0005] PTL3 describes a film-coated glass plate in which a layer film, obtained by stacking a plurality of films, is formed on a glass plate, and the layer film comprises an inorganic film containing at least one noble metal and formed on the glass plate, and a coating metal film formed on the inorganic film. According to PTL3, the layer film is black when viewed from the side of the glass plate. List of references Patent literature [PTL1] Japanese Unexamined Patent Publication No. 2014-150118 [PTL2] Japanese Unexamined Patent Publication No. 2015-229260 [PTL3] Japanese Unexamined Patent Publication No. 2016-74582 DEPICTION

[0006] In the metal mesh described in PTL1 and PTL2, a black surface can be formed by providing a blackening metal layer. Accordingly, the invisibility of the metal mesh can be improved to a certain extent. However, investigations by the inventors have indicated that there is still room for improvement in the metal mesh itself with regard to high reflectivity.

[0007] In the case of the film-coated glass plate described in PTL3, it was difficult to improve the adhesion between the glass plate and the film coating.

[0008] The present invention was made in view of the circumstances described above and is directed to suppressing reflection while improving the adhesion between a base material and a coating film with respect to a metal mesh formed from the coating film provided on the base material and a film material for producing the metal mesh.

[0009] The present invention provides a sheet material comprising a resin layer containing a binder and a plurality of polypyrrole particles, a powerless coating film provided on one side of the resin layer and comprising first powerless coating films and a second powerless coating film, and a transparent base material provided on the other side of the resin layer. At least a fraction of the plurality of polypyrrole particles each have exposed surfaces on one of the main surfaces of the resin layer, and the plurality of exposed surfaces are distributed on this one main surface of the resin layer.The first electroless-generated coating films are provided on one main surface of the resin layer to surround the multitude of exposed surfaces of the polypyrrole particles, and the second electroless-generated coating film is provided to cover the first electroless-generated coating films, and one main surface, on the side of the first electroless-generated coating films, of the second electroless-generated coating film forms concave sections along surfaces of the first electroless-generated coating films.

[0010] In the surface material according to the present invention, reflection can be prevented, while the adhesion between the transparent base material and the coating film can be improved.

[0011] When considering the one main surface of the resin layer in a top view from the side of the electroless-generated coating film, the average value of the respective longest diameter of the first electroless-generated coating films can be 18 to 90 nm, and the area ratio of the first electroless-generated coating films to the one main surface can be 80 to 99%.

[0012] A main surface, on the opposite side to the first electroless-generated coating films, of the second electroless-generated coating film can be a rough surface.

[0013] The present invention also provides a method for producing the sheet material described above according to the present invention. The method for producing a sheet material according to the present invention comprises a step of forming a resin layer comprising a binder and a plurality of polypyrrole particles on a transparent base material, wherein at least a portion of the plurality of polypyrrole particles each have exposed surfaces that are exposed on one main surface of the resin layer, the plurality of exposed surfaces being distributed on one main surface of the resin layer, and the transparent base material being provided on the side of the other main surface of the resin layer; a step in which a solution comprising a catalyst is brought into contact with the exposed surfaces of the polypyrrole particles to form catalyst cores.which adhere to the multitude of exposed surfaces, a step of forming first electroless-generated coating films on one main surface of the resin layer to surround each of the multitude of exposed surfaces and the catalyst cores, and a step of forming a second electroless-generated coating film to cover the first electroless-generated coating films, wherein a main surface, on the side of the first electroless-generated coating films, of the second electroless-generated coating film forms concave sections along surfaces of the first electroless-generated coating films.

[0014] The present invention further provides a method for producing a metal mesh, comprising a step of performing etching for the electroless produced coating film in the above-described surface material according to the present invention to form an electroless produced coating film with a mesh-like structure.

[0015] As one aspect of the metal mesh, the present invention provides a metal mesh (hereinafter referred to as the "first metal mesh") comprising a resin layer containing a binder and a plurality of polypyrrole particles, a powerless-generated coating film provided to form a mesh-like structure on the side of one principal surface of the resin layer and comprising first powerless-generated coating films and a second powerless-generated coating film, and a transparent base material provided on the side of the other principal surface of the resin layer. In the first metal mesh, at least a portion of the plurality of polypyrrole particles each have exposed surfaces that are exposed on one principal surface of the resin layer, and the plurality of exposed surfaces are distributed on one principal surface of the resin layer.The first electroless-generated coating films are provided on one major surface of the resin layer to surround the multitude of exposed surfaces of the polypyrrole particles. The second electroless-generated coating film is provided to cover the first electroless-generated coating films, and one major surface, on the side of the first electroless-generated coating films, of the second electroless-generated coating film forms concave sections along the surfaces of the first electroless-generated coating films.

[0016] As a further aspect of a metal mesh, the present invention provides a metal mesh (hereinafter referred to as the "second metal mesh") comprising a transparent base material, a resin layer provided to form a mesh-like structure on the transparent base material and comprising a binder and a plurality of polypyrrole particles, and an electroless-generated coating film provided on the transparent base material along the mesh-like structure of the resin layer while covering the resin layer, and comprising first electroless-generated coating films and a second electroless-generated coating film. In the second metal mesh, at least a portion of the plurality of polypyrrole particles each have exposed surfaces that are exposed on a surface of the resin layer, and the plurality of exposed surfaces are distributed on the surface of the resin layer.The first electroless-generated coating films are provided on the surface of the resin layer to surround the multitude of exposed surfaces of the polypyrrole particles. The second electroless-generated coating film is provided to cover the first electroless-generated coating films, and an area of ​​the second electroless-generated coating film, on the side of the first electroless-generated coating films, forms concave sections along the surfaces of the first electroless-generated coating films.

[0017] In the metal mesh described above according to the present invention, reflection can be prevented, while the adhesion between the transparent base material and the coating film can be improved.

[0018] In the metal mesh described above, an area on the opposite side of the first electroless-generated coating film and the second electroless-generated coating film can be a rough surface.

[0019] According to the present invention, a surface material in which reflection can be prevented while maintaining high adhesion between a base material and a coating film, and a manufacturing process for this surface material, can be provided. According to the present invention, a metal mesh with a similar effect to that of the surface material described above, and a manufacturing process for this mesh, can also be provided. List of characters Fig. Figure 1 is a schematic sectional view showing one embodiment of a surface material; Fig. 2 is a schematic sectional view showing another embodiment of the surface material; Fig. Figure 3 is a schematic view showing one embodiment of the manufacturing steps of a metal mesh; Fig. Figure 4 is a schematic view showing another embodiment of steps for producing a metal mesh. DETAILED DESCRIPTION

[0020] Preferred embodiments of the present invention are described in detail below with reference to the drawings. [Surface material]

[0021] Fig. Figure 1 is a schematic sectional view representing one embodiment of a surface material. As in Fig. 1 shown comprises a surface material 1 according to the present embodiment, a resin layer 4 , which is a binding agent 2 and contains a large number of polypyrrole particles, forming a coating film produced without electricity 7 , which is on the side of a main surface 4a the resin layer4 is planned and the first electrically generated coating films 5 and a second coating film produced without electricity 6 features, and a transparent base material 8 , which is on the side of the other main surface 4b the resin layer 4 is intended. A portion of the polypyrrole particles 3 Each has exposed surfaces 3a , which are located on the main surface 4a the resin layer 4 be exposed, and the multitude of exposed surfaces 3a is on one main surface 4a the resin layer 4 Scattered. The first coating films produced without electricity. 5 are on one main area 4a the resin layer 4 designed to accommodate the multitude of exposed surfaces 3a the multitude of polypyrrole particles 3 to surround, the second electrically generated coating film 6is intended to produce the first coating films without electricity 5 to cover, and a main area 6a , on the page of the first electrically produced coating films 5 , of the second electrically generated coating film 6 forms concave sections 6r each along the surfaces of the first electrically generated coating films 5 .

[0022] The surface material described above 1 This makes it possible to prevent reflection while improving the adhesion between the base material and the coating film when they are used to form a metal mesh. The inventors believe the reason for this is as follows.

[0023] Initially, it is assumed that the reason why reflection cannot be minimized in a conventional metal mesh coated with a blackening metal layer is that the blackening metal layer is uniform, meaning that a large portion of the blackening metal layer has a smooth surface. In contrast, with the sheet material... 1 according to the present invention, the first electrically generated coating films 5 on the main area 4a the resin layer 4 designed to protect the exposed surfaces 3a the multitude of polypyrrole particles 3 to surround. Accordingly, there are few areas with a smooth surface, which is why it is assumed that reflection can be kept low. In addition, the coating film is generated without electricity. 7 and the transparent base material 8 with the resin layer inserted between them4 stacked, which is why it is assumed that an adhesive property exists between the electrically generated coating film. 7 and the transparent base material 8 can be improved.

[0024] Although the binder 2 is not specifically limited, examples of the binding agent include 2Resins based on polyvinyl chloride, polycarbonate, polystyrene, polymethyl methacrylate, polyester, polysulfone, polyphenylene oxide, polybutadiene, poly(N-vinylcarbazole), hydrocarbon, ketone, phenoxy, polyamide, ethylcellulose, vinyl acetate, acrylonitrile butadiene (ABS), urethane, melamine, acrylate, unsaturated polyester, alkyd, epoxy, and silicon. It is preferred that the binder 2contains a melamine-based resin to further improve coating deposition and adhesion properties while maintaining transparency of the resin layer 4 to ensure.

[0025] It is preferred that the polypyrrole particles 3 have an average particle diameter of 10 to 100 nm, and it is particularly preferred that the polypyrrole particles 3 have an average particle diameter of 20 to 50 nm. If the average particle diameter of the polypyrrole particles 3Within the numerical range described above, reflection can be more effectively suppressed by manufacturing the surface material and the metal mesh. The average particle diameter is measured using a laser diffraction scattering method and can be calculated as a value corresponding to a particle diameter at 50% of the cumulative volume when a curve of the particle size distribution of the cumulative volume is plotted from the side of a small particle diameter.

[0026] Although a mass ratio of the binder 2 and the polypyrrole particle 3 in the resin layer 4Since the specific requirements are not limited, it is preferred that the mass ratio of the binder to the polypyrrole particles is, for example, 2:1 to 15:1, for instance, with a view to efficiently forming the electroless-generated coating film and more effectively suppressing reflection. Although the thickness of the resin layer 4 Since the thickness is not specifically limited, it is preferred that it be 10 to 100 nm, and it is particularly preferred that the thickness be, for example, 50 to 80 nm, for example, with a view to ensuring the transparency of the resin layer while at the same time suppressing reflection more effectively.

[0027] It is preferred that the first electroless-generated coating film 5Contains at least one type of metal selected from a group consisting of nickel, palladium, gold, silver and their compounds to more effectively suppress reflection, to promote invisibility, and to ensure advantageous etching behavior (preventing interruption by over-etching) when the currentless-generated coating film 7 The coating film is structured by means of etching. It is particularly preferred that the first electroless-generated coating film is 5 It also contains phosphorus to more effectively ensure the etching behavior described above. The phosphorus content can be adjusted accordingly. 8 Mass percent or less of the total mass of the first electrically produced coating films 5 be.

[0028] It is preferred that the average value of the respective longest diameters of the first electroless produced coating films be used. 518 to 90 nm when the one main surface 4a the resin layer 4 in a top view from the side of the electrically generated coating film 7 is considered. If the average value of the respective longest diameters of the first electroless-generated coating films is 5 If the wavelength is 18 nm or more, reflection can be made more effective using the first currentless coating films. 5 This can be prevented. If the average value is 90 nm or less, areas with a smooth surface can occur in the first, electrically generated coating films. 5 They will occur less frequently, and as a result, reflection can be suppressed more effectively.

[0029] It is preferred that the area ratio of the first electrically generated coating films 5 to the one main area 4a the resin layer 4 80 to 99% if the one main area 4athe resin layer 4 in a top view from the side of the electrically generated coating film 7 is considered. If the area ratio is 80% or more, reflection can be made more effective using the first currentless generated coating films. 5 This can be prevented. If the surface area ratio is 99% or less, areas with a smooth surface can occur in the first electrically generated coating films. 5 They will occur less frequently, and as a result, reflection can be suppressed more effectively.

[0030] The average value of the longest diameters of the first electroless produced coating films 5 and the area ratio of the first electrically generated coating films 5 to the one main area 4a the resin layer 4This can be measured by image analysis of a scanning electron microscope (SEM) image. Specifically, the average value of the longest diameters of the first electroless coating films can be determined. 5 by observing the surface material 1 with a 200,000x magnification from the side of the electrically generated coating film 7 , Capturing an image of the SEM image in a field of view of 500 µm length and 600 µm width, actual measurement of the respective longest diameters of the first currentless produced coating films 5 in the field of view, and an average value of the respective actual measured values ​​is calculated. The area ratio can be determined by measuring the respective surface areas of the first electroless-generated coating films based on their longest and shortest diameters. 5within the field of view, and calculating a ratio of the total value of the areas to the area of ​​the field of view.

[0031] It is preferred that the second coating film be produced without electricity. 6 at least one type of metal selected from the group consisting of copper, nickel, silver, and their compounds, and it is particularly preferred that the second electroless-generated coating film 6 , from the point of view of reducing electrical resistance, contains copper. Although the first currentless-generated coating films described above 5 and the second coating film produced without electricity 6 Since the coating films may contain metals or metal compounds of the same type or of different types, it is preferred that the first electroless-generated coating films 5 and the second coating film produced without electricity 6each contain metals or metal compounds of different types, and it is particularly preferred that the first electroless-generated coating films 5 Nickel or a nickel compound, and the second electroless-generated coating film 6 Contains copper.

[0032] Although the thickness of the second electrically generated coating film 6 Since the thickness is not specifically limited, it is, for example, preferred that it be 0.3 µm to 10 µm, and it is particularly preferred that it be 0.5 µm to 10 µm to suppress reflection more effectively. This is especially true if the thickness of the second currentless-generated coating film is 6 If the thickness is 0.3 µm or greater, the permeability of the second currentless-generated coating film may be affected. 6 can be maintained more effectively.

[0033] Although not particularly limited, the transparent base material contains 8preferably at least one type selected from a group consisting of polyethylene terephthalate (PET), polyethylene naphthalate, and polyimide, in order to easily obtain a sheet material with high transmission and low reflection. Although the thickness of the transparent base material 8 Since the thickness is not specifically limited, it is preferred that it be, for example, 3 to 50 µm to suppress reflection more effectively.

[0034] The surface material according to the present embodiment can accommodate catalyst cores (not shown), e.g., between the exposed surfaces. 3a the multitude of polypyrrole particles 3 and the first electrically produced coating films 5 exhibiting. Once the catalyst cores are provided, the respective adhesive properties between the polypyrrole particles can be observed. 3 and the first electrically produced coating films 5further improvements will be made, while the respective longest diameters of the first electrically generated coating films will be further improved. 5 and the area ratio of the first electrically generated coating films 5 to the one main area 4a the resin layer 4 As described above, it can be adjusted more efficiently to desired values. At least one type of metal can be selected from a group consisting of palladium, silver, platinum, gold, nickel, copper, and their compounds to serve as the catalyst core. Although the quantity and size of each catalyst core are not specifically limited, the amount of catalyst core can be adjusted to between 0.1 and 1.8 µg / cm³. 2 be set, and the size of the catalyst core can be set from 3 to 120 nm.

[0035] Fig. Figure 2 is a schematic sectional view showing another embodiment of a surface material. As in Fig.2 shown can be used with a surface material 1 according to the present embodiment, a main surface 6b on the opposite side of the first electrically generated coating films 5 , a second electrically generated coating film 6 a rough surface 6s The visibility of the surface material can be affected accordingly. 1 will be further improved.

[0036] The surface material 1 According to the present embodiment, the following method can be used, for example. In other words, a method for producing the surface material comprises 1 according to the present embodiment, a step (first step) of forming a resin layer 4 , which is a binding agent 2 and a variety of polypyrrole particles 3 contains, on a transparent base material 8, whereby at least a portion of the multitude of polypyrrole particles 3 exposed surfaces 3a exhibits which are located on a main surface 4a the resin layer 4 exposed, with the multitude of exposed surfaces 3a on one main surface 4a the resin layer 4 are scattered, and the transparent base material 8 on the side of the other main surface 4b the resin layer 4 is provided, a step (second step) in which a solution containing a catalyst is made to coat the exposed surfaces 3a the polypyrrole particles 3 to touch in order to form catalyst cores, each of which is attached to the multitude of exposed surfaces 3a adhere, a step (third step) in the formation of the first electrically generated coating films 5 on one main surface 4a the resin layer 4, in order to examine the multitude of exposed surfaces 3a and to surround the catalyst cores, and a step (fourth step) of forming a second currentless-generated coating film 6 , to produce the first coating films without electricity 5 to cover, with a main area 6a , on the page of the first electrically produced coating films 5 , of the second electrically generated coating film 6 concave sections 6r each along the surfaces of the first electrically generated coating films 5 educates.

[0037] Examples of the process for forming the resin layer 4 on the transparent base material 8The first step comprises a process for producing a resin composition containing a binder and polypyrrole particles, and the application of the resulting resin solution to a transparent base material, followed by drying. The first step yields a stacked body (first stacked body) comprising a transparent base material and a resin layer containing a binder and a plurality of polypyrrole particles on the transparent base material, wherein at least a portion of the plurality of polypyrrole particles each have exposed surfaces that are exposed on one principal surface of the resin layer, and the plurality of exposed surfaces are distributed on one principal surface of the resin layer. Although a mass ratio of the binder and the polypyrrole particles in the resin composition is not specifically limited, it is preferred that a mass ratio of the binder to the polypyrrole particles be, for example,The ratio can be 2:1 to 15:1 to more effectively prevent reflection.

[0038] Examples of the process for forming the catalyst cores in the second step include a method for immersing the first stack obtained in the first step into a solution containing a catalyst, followed by rinsing or the like. Accordingly, catalyst cores can be specifically adsorbed onto the exposed surfaces of the polypyrrole particles. The second step can then yield a stack (second stack) in which the catalyst cores are formed, each adhering to the multitude of exposed surfaces in the first stack.

[0039] Examples of the process for forming the first electroless-generated coating films in the third step include a method for immersing the second stack obtained in the second step into a first electroless coating bath containing a predetermined metal, followed by rinsing or the like. Although a processing condition for the first electroless coating bath is not specifically limited, a processing temperature, for example, is 70 to 90 °C and a processing time is 10 to 120 seconds when using a first electroless coating bath containing 0.1 to 2.0 grams of a predetermined metal per liter.The third step yields a stacked body (third stacked body) in which first electroless-generated coating films are formed on one main surface of the first resin layer to surround the multitude of exposed surfaces and catalyst cores in the second stacked body.

[0040] Examples of the process for forming the second electroless-generated coating film 6The fourth step comprises a method for immersing the third stack obtained in the third step into a second electroless coating bath containing a specified metal, followed by rinsing or the like. Although the processing conditions of the second electroless coating bath are not specifically limited, a processing temperature may, for example, be 25 to 50 °C, and a processing time may be 5 to 60 minutes, when using a second electroless coating bath containing 1 to 5 grams of a specified metal per liter.The fourth step allows a surface material to be formed in which a second electroless-generated coating film is formed to cover the first electroless-generated coating films in the third stack body, and in which a main surface, on the side of the first electroless-generated coating films, of the second electroless-generated coating film forms concave sections along surfaces of the first electroless-generated coating films.

[0041] A method for producing the surface material according to the present embodiment can further comprise a step of roughening the main surface, on the opposite side of the first electroless coating film, of the second electroless coating film, after the fourth step described above. In the roughening process, a rough surface can be formed, for example, by roughening machining or by coating machining. [First metal mesh]

[0042] A first metal mesh according to the present embodiment comprises a resin layer containing a binder and a plurality of polypyrrole particles, an electroless-generated coating film provided to form a mesh-like structure on the side of a principal surface of the resin layer and comprising first electroless-generated coating films and a second electroless-generated coating film, and a transparent base material provided on the side of the other principal surface of the resin layer.At least some of the polypyrrole particles have exposed surfaces that are exposed on one main surface of the resin layer; the multiple exposed surfaces are scattered on one main surface of the resin layer; the first electroless-generated coating films are provided on one main surface of the resin layer to surround each of the exposed surfaces of the polypyrrole particles; the second electroless-generated coating film is provided to cover the first electroless-generated coating films; and one main surface, on the side of the first electroless-generated coating films, of the second electroless-generated coating film forms concave sections along each surface of the first electroless-generated coating films.

[0043] The first metal mesh can be produced in the above-described surface material according to the present embodiment by means of etching for the electroless-generated coating film, in order to form, for example, an electroless-generated coating film with a mesh-like structure.

[0044] Fig. Figure 3 is a schematic view showing one embodiment of the steps for producing a first metal mesh. 10 illustrated. As in Fig. 3 shows first a surface material 1 manufactured according to the present embodiment ( Fig. 3A), and a net-like resist structure 9 is applied to a main surface, on one of the resin layers 4 opposite side, of a coating film produced without electricity 7 in the surface material 1 ( Fig. 3B). Although a method for forming the network-like resist structure 9While not specifically limited, a known method can be used if necessary. Examples of such methods include a method for forming a network-like resist structure using a printing process, an inkjet process, a photolithographic process, or the like, and a method for forming a resist film, followed by subjecting the resist film to structuring exposure and development to structure the resist film into a network. The electroless-generated coating film is then 7 using the resist structure 9 etched as a mask to create a power-free generated coating film 7' to form a net-like structure, and the resist structure 9 will be removed ( Fig. 3C). Accordingly, the electroless generated coating film can 7' , who produced the first coating films without electricity 5' and a second coating film produced without electricity 6'includes being formed with a net-like structure.

[0045] A second metal mesh according to the present embodiment comprises a transparent base material, a resin layer provided to form a mesh-like structure on the transparent base material, a binder containing a plurality of polypyrrole particles, and an electroless-generated coating film provided on the transparent base material along the mesh-like structure of the resin layer while covering the resin layer and comprising first electroless-generated coating films and a second electroless-generated coating film.At least some of the polypyrrole particles have exposed surfaces on a surface of the resin layer; the exposed surfaces are scattered on the surface of the resin layer; the first electroless-generated coating films are spread across the surface of the resin layer to surround the exposed surfaces of the polypyrrole particles; the second electroless-generated coating film is provided to cover the first electroless-generated coating films; and a major surface of the second electroless-generated coating film, on the side of the first electroless-generated coating films, forms concave sections along surfaces of the first electroless-generated coating films.

[0046] The second metal mesh can be produced, for example, by the following method.

[0047] Fig.Figure 4 is a schematic view showing one embodiment of the steps for producing a second metal mesh. 20 illustrated. As in Fig. 4 shows a layer of resin. 4' with a net-like structure on a transparent base material 8 formed ( Fig. 4A). Although a method for forming the resin layer 4' Although the net-like structure is not specifically limited, known methods can be used if necessary, and examples of the method include a method for forming the resin layer. 4' with the net-like structure by means of a printing process, an inkjet process, a photolithographic process, and the like.

[0048] Then, a solution containing a catalyst is brought into contact with exposed surfaces of a multitude of polypyrrole particles located on the surface of the resin layer. 4'The particles are scattered and brought together to form catalyst cores, each adhering to the multitude of exposed surfaces. Then, the first electroless coating films are produced. 5' on the surface of the first resin layer 4' formed so that they surround the multitude of exposed surfaces and the catalyst cores. This serves as a method for forming the catalyst cores and the first electroless coating films. 5' A similar procedure can be used as the one used in the above-described process for producing the surface material.

[0049] If then a second coating film is produced without electricity 6' on the transparent base material 8 is formed, so that it forms the resin layer 4' and the first coating films produced without electricity 5' When covered, a second metal mesh can be formed ( Fig.4B). Here, a main surface is formed on the side of the first electrically generated coating films. 5' , of the second electrically generated coating film 6' concave sections along the surfaces of the first electrically generated coating films 5' . As a method for forming the second, currentless coating films 6' A similar process can be used as the process used in the above-described process for producing the surface material.

[0050] The surface material and the metal mesh according to the present embodiment, described above, can be advantageously used for a sensor of a touchscreen of a smartphone, tablet device, PC, or the like, because reflection can be prevented while maintaining a high level of adhesion between the base material and the coating film. The reflection in the surface material and the metal mesh, which can be advantageously used for the touchscreen sensor, is 20% or less, for example preferably 15% or less, and particularly preferably 10% or less.

[0051] The surface material according to the present embodiment can, if required, be used to produce a wiring substrate by carrying out an etching step for the electroless-generated coating film, in order to form an electroless-generated coating film with a wiring pattern. A display device can also be obtained by further mounting an electronic component, such as a light-emitting element, or a passive component, on the wiring substrate, if required. EXAMPLES

[0052] Although the present invention is specifically described below with reference to examples and comparative examples, the present invention is not limited to the following examples. [Production of the surface material](Example) 1 )

[0053] 1.5 mmol of an anionic surfactant PELEX OT-P (trade name, manufactured by Kao Corporation), 50 mL of toluene, and 100 mL of ion-exchange water were mixed and stirred while maintained at 20 °C to obtain an emulsion. 21.2 mmol of a pyrrole monomer was added to the emulsion, followed by stirring for one hour, and 6 mmol of ammonium persulfate were added, followed by a polymerization reaction for two hours. After completion of the reaction, an organic layer was obtained and repeatedly washed with the ion-exchange water to obtain polypyrrole particles with an average particle diameter of 40 nm, dispersed in the toluene.

[0054] Five parts by mass of SUPER BECKAMINE J-820 (trade name, manufactured by DIC Corporation) were added as a binder to one part by mass of the obtained polypyrrole particles to create a resin composition (the binder-to-polypyrrole particle mass ratio was 5:1). The resulting resin composition was applied to a PET film (trade name "COSMOSHINE A4100," manufactured by TOYOBO CO. LTD.) and subsequently dried to obtain a first stacked body containing a 60 µm thick resin layer on the PET film, with polypyrrole particles exhibiting exposed surfaces.

[0055] The first stack was then immersed in a solution containing 1 gram of palladium ions per liter, followed by rinsing. The first stack was further immersed in a solution containing 10 grams of hypophosphoric acid per liter, followed by rinsing, to obtain a second stack with catalyst cores adsorbed onto exposed surfaces of the polypyrrole particles formed therein. The second stack was immersed in an electroless coating bath containing 0.5 grams of nickel ions per liter, and electroless coating was performed for 20 seconds at a temperature of 82 °C to obtain a third stack with initial electroless coating films, each exhibiting an uneven surface.The third stack was then immersed in an electroless coating bath containing 3 grams of copper ions per liter, and electroless coating was carried out for 45 minutes. The coating bath was set to a temperature of 38 °C to produce a sheet material in which a second electroless coating film was formed on the respective uneven surfaces of the first electroless coating films. The thickness of the second electroless coating film was 1 µm, and concave sections were formed along the surfaces of the first electroless coating films. (Example 2)

[0056] A similar process to that in Example 1 was carried out, except that the time period during which the first stacked body was immersed in the electroless coating bath containing nickel ions was set to 30 seconds in order to obtain a sheet material. (Example 3)

[0057] A similar process to that in Example 1 was carried out, except that the immersion time of the first stacked body in the electroless coating bath containing nickel ions was set to 40 seconds to obtain a sheet material. (Example 4)

[0058] A similar process to that in Example 1 was carried out, except that the immersion time of the first stacked body in the electroless coating bath containing nickel ions was set to 50 seconds to obtain a sheet material. (Example 5)

[0059] A similar process to that in Example 1 was carried out, except that the immersion time of the first stacked body in the electroless coating bath containing nickel ions was set to 60 seconds to obtain a sheet material. (Example 6)

[0060] A similar process to that in Example 1 was carried out, except that the immersion time of the first stacked body in the electroless coating bath containing nickel ions was set to 90 seconds to obtain a sheet material. (Example 7)

[0061] A similar process to that in Example 1 was carried out, except that the immersion time of the first stacked body in the electroless coating bath containing nickel ions was set to 120 seconds to obtain a sheet material. (Comparative example 1)

[0062] Palladium was formed as a 20 nm thick film on a PET film (trade name "COSMOSHINE A4100", manufactured by TOYOBO CO. LTD) using a sputtering process to obtain a stacked body. This stacked body was then immersed in an electroless coating bath containing 0.5 grams of nickel ions per liter and processed for 20 seconds at a temperature of 82 °C to form a third stacked body with the first electroless coating films, each with a smooth surface.The third stack was then immersed in a solution containing 0.1 grams of palladium ions per liter, followed by rinsing, and then immersed in an electroless coating bath containing 3 grams of copper ions per liter. Electroless coating was carried out for 45 minutes in a bath temperature of 38 °C to obtain a sheet material in which a second electroless coating film containing copper was formed on the respective surfaces of the first electroless coating films containing nickel. The thickness of the second electroless coating film containing copper was 1 µm. (Comparative example 2)

[0063] Nickel was formed as a 20 nm thick film on a PET film (trade name "COSMOSHINE A4100," manufactured by TOYOBO CO. LTD) using a sputtering process to create a third stack body containing films with smooth surfaces. This third stack body was then immersed in a solution containing 0.1 grams of palladium ions per liter, followed by rinsing, and then in a solution containing 10 grams of hypophosphoric acid per liter, again followed by rinsing. The third stack body was then immersed in an electroless coating bath containing 3 grams of copper ions per liter and electroless coating was performed for 45 minutes at a temperature of 38°C to obtain a sheet material in which the second electroless-generated coating film, containing copper, was formed on the respective surfaces of the nickel-containing films.The thickness of the electroless produced coating film was 1 µm. (Comparative example 3)

[0064] A PET film (trade name “COSMOSHINE A4100”, manufactured by TOYOBO CO. LTD) was immersed in a colloidal Sn-Pd solution for five minutes at a temperature of 25°C, followed by rinsing, and then immersed in an electroless coating bath containing 0.5 grams of nickel ions per liter, and electroless coating was carried out for 20 seconds, with the coating bath set to a temperature of 82°C, to obtain a third stack body with first electroless-generated coating films formed therein, each having an uneven surface.The third stack was then immersed in a solution containing 0.1 grams of palladium ions per liter, followed by rinsing, and then immersed in an electroless coating bath containing 3 grams of copper ions per liter, and electroless coating was carried out for 45 minutes, with the coating bath set to a temperature of 38°C to obtain a surface material in which a second electroless-generated coating film containing copper was formed on the respective uneven surfaces of the nickel-containing films. [Evaluation of the surface material](Measurement of the longest diameters and the area ratio of the first electroless-generated coating films)

[0065] The longest diameters and area ratios of the first electroless-produced coating films in each of the third stack bodies obtained in the examples and comparison examples described above were measured using image analysis of a SEM scan. The measurement was performed by observing each of the third stack bodies at 200,000x magnification within a field of view 500 µm long and 600 µm wide to calculate an average value for the longest diameters and area ratios of the first electroless-produced coating films within that field of view. It should be noted that the respective surface area of ​​the films in the third stack body, which in each of the comparison examples 1 and 2 The surface was smooth, and therefore the longest diameters could not be measured. One measurement result is shown in Table 1. (Measurement of reflection)

[0066] The reflection of light from the side of the PET film in the sheet material obtained in each of the examples and comparison example was measured according to a procedure that meets the requirements of JIS K 8729, using a CM-5 spectrophotometer (product name, manufactured by Konica Minolta, Inc.). A measurement result is shown in Table 1. If the reflection is 20% or less, the sheet material can be considered a good sheet material, in which reflection is kept low. [Production of the metal mesh]

[0067] A network-like resist structure with 5 µm conduits (L) and 10 µm spaces (S) was formed by photolithography on the electroless-generated coating film in the sheet material obtained in each of the examples and comparison examples. The resist pattern was then immersed in a 5% sodium persulfate solution and etched for 5 minutes at 25°C to remove the resist, thereby creating a metal network. [Evaluation of the metal mesh](Evaluation of the adhesive properties)

[0068] The resulting metal mesh was wound around a stainless steel rod with a diameter of 1 mm to evaluate the adhesion properties of the electrically generated coating film according to the following evaluation criteria. The result is shown in Table 1.

[0069] A: No peeling of the coating film was observed, even after the metal mesh 500 was wound or rewound.

[0070] B: Delamination of the coating film was observed, where the metal mesh was wound less than 500 times. (Assessment of behavior during etching)

[0071] The presence or absence of a conductor break due to etching was visually inspected, and etching behavior was evaluated according to the following assessment criteria. The results are shown in Table 1.

[0072] A: No interruption of the line was detected when the etching was performed.

[0073] B: Interruption of the line was detected when the etching was carried out. [Table 1] Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Example 7 Comparative example 1 Comparative example 2 Comparative example 3 Average value of longest diameters (nm) 18 20 25 30 35 60 90 smooth smooth 120 Area ratio (%) 85,0 90,0 95,0 96,0 98,0 99,0 99,0 100 100 50-80 Reflectance (%) 18,0 9,5 3,7 6,7 9,7 12,3 13,3 31,0 25,0 23,0 Liability A A A A A A A A A B Behavior during etching A A A A A A A B A A

[0074] As can be seen from the respective results of Examples 1 to 7, the reflectance of the sheet material according to the present invention could be kept low, while the adhesion between the base material and the coating film could be improved. Furthermore, no interruption of conductivity was observed during etching, demonstrating that the sheet material exhibits excellent etching behavior.

[0075] In a comparative example 1 In contrast, in which a palladium film was applied to the PET film using a sputtering process, and then the nickel coating films were formed, and in the comparative example 2In the experiment where the nickel films were formed directly on the PET film using the sputtering process, almost all nickel-containing films formed a continuous film with a smooth surface, which meant that the reflectance could not be kept low. Furthermore, when the films were provided as in the comparative example... 1 The copper plating film was preferentially etched, indicating that the circuit was slightly interrupted. In a comparative example... 3In a process where the PET film is immersed in the colloidal Sn-Pd solution to cause the palladium particles to adhere to the PET film, and then the nickel coating films are formed, the coating films were formed without the use of a resin layer. Consequently, the palladium particles did not adhere sufficiently to the PET film, thus ensuring adequate adhesion. The coating film that formed in the area where the palladium particles did not adhere resulted in a continuous film with a smooth surface, which prevented low reflectivity.

Claims

[1] Surface material comprising: a resin layer comprising a binder and a variety of polypyrrole particles; an electroless-generated coating film provided on the side of a main surface of the resin layer, comprising first electroless-generated coating films and a second electroless-generated coating film; and a transparent base material provided on the side of the other main surface of the resin layer, wherein at least some of the multitude of polypyrrole particles each have exposed surfaces that are exposed on one main surface of the resin layer, and the multitude of exposed surfaces is distributed on one main surface of the resin layer, the first electrically generated coating films are provided on one main surface of the resin layer to surround the multitude of exposed surfaces of the polypyrrole particles, and The second electroless-generated coating film is provided to cover the first electroless-generated coating films, and a main surface, on the side of the first electroless-generated coating films, of the second electroless-generated coating film forms concave sections along surfaces of the first electroless-generated coating films. [2] Surface material according to claim 1, wherein an average value of the longest diameters of the first electroless produced coating films is 18 to 90 nm when one main surface of the resin layer is viewed in a top view from the side of the electroless produced coating film. [3] Surface material according to claim 1 or 2, wherein the area ratio of the first electroless produced coating films to the one main surface of the resin layer is 80 to 99% when the one main surface is viewed in a top view from the side of the electroless produced coating film. [4] Surface material according to one of claims 1 to 3, wherein a main surface on the opposite side of the first electroless produced coating films, of the second electroless produced coating film is a rough surface. [5] Method for producing a sheet material, comprising: a step of forming a resin layer comprising a binder and a plurality of polypyrrole particles on a transparent substrate, wherein at least a portion of the plurality of polypyrrole particles each has exposed surfaces that are exposed on a principal surface of the resin layer, wherein the plurality of exposed surfaces is distributed on the one principal surface of the resin layer, and the transparent base material is provided on the side of the other main surface of the resin layer; a step in which a solution containing a catalyst is brought into contact with the exposed surfaces of the polypyrrole particles to form catalyst cores, each of which adheres to the multitude of exposed surfaces; a step of forming initial currentless coating films on one main surface of the resin layer, in order to surround the multitude of exposed surfaces and the catalyst cores; and a step of forming a second currentless-generated coating film to cover the first currentless-generated coating films, wherein a main area, On the side of the first electroless-generated coating films, concave sections are formed along the surfaces of the first electroless-generated coating films, as well as on the side of the second electroless-generated coating film. [6] Method for producing a metal mesh, comprising a step of performing an etching for the electroless produced coating film in the sheet material according to any one of claims 1 to 4, to form an electroless produced coating film with a mesh-like structure. [7] Metal mesh, comprising: a resin layer comprising a binder and a plurality of polypyrrole particles; an electroless-generated coating film provided to form a net-like structure on the side of one principal surface of the resin layer, comprising first electroless-generated coating films and a second electroless-generated coating film; and a transparent base material provided on the side of the other principal surface of the resin layer, wherein at least a portion of the plurality of polypyrrole particles each has exposed surfaces that are exposed on one principal surface of the resin layer, and the plurality of exposed surfaces is distributed on one principal surface of the resin layer. the first electrically generated coating films are provided on one main surface of the resin layer to surround the multitude of exposed surfaces of the polypyrrole particles, and The second electroless-generated coating film is provided to cover the first electroless-generated coating films, and a main surface, on the side of the first electroless-generated coating films, of the second electroless-generated coating film forms concave sections along surfaces of the first electroless-generated coating film. [8] Metal mesh, comprising: a transparent base material; a resin layer provided to form a net-like structure on the transparent base material and comprising a binder and a plurality of polypyrrole particles; and an electroless-generated coating film provided on the transparent base material along the net-like structure of the resin layer while the resin layer is being covered, and comprising a first electroless-generated coating film and a second electroless-generated coating film, wherein at least a portion of the polypyrrole particles each have exposed surfaces that are exposed on a surface of the resin layer, and the plurality of exposed surfaces is distributed on the surface of the resin layer. the first electrically generated coating films are provided on the surface of the resin layer to surround the multitude of exposed surfaces of the polypyrrole particles, and the second electroless-generated coating film is provided to cover the first electroless-generated coating films, and a surface, on the side of the first electroless-generated coating films, of the second electroless-generated coating film forms concave sections each along surfaces of the first electroless-generated coating films. [9] Metal mesh according to claim 7 or 8, wherein a surface on the opposite side of the first electroless produced coating films, of the second electroless produced coating film is a rough surface.

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