Conductive composition for molded film, molded film and method for manufacturing the same, molded article and method for manufacturing the same

Abstract

To provide a conductive composition for a molding film that enables manufacture of a molding film in which lowering of conductivity by tensile force at high speed under a high temperature condition is suppressed.SOLUTION: A conductive composition for a molding film contains a resin (A), conductive fine particles (B), and a solvent (C), wherein the resin (A) is any one of a group consisting of a polyester resin, a polyurethane resin, a polyamide resin, and a polycarbonate resin, and contains a resin (A1) including a trifunctional monomer or a tetrafunctional monomer-derived structural unit.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a conductive composition for a formed film, a formed film and a method for producing the same, a formed body and a method for producing the same.

Background Art

[0002] Patent Document 1 discloses a specific integrated conductive circuit molded product having a resin molded body, a base film embedded flush with one surface of the resin molded body, and a conductive circuit disposed between the resin molded body and the base film. Patent Document 1 describes, as a method for manufacturing the integrated conductive circuit molded product, after disposing a base film on which a specific conductive circuit is formed on the cavity surface of an injection mold, injecting molten resin to injection-mold the resin molded body. In Patent Document 1, the conductive circuit is formed by etching a specific transparent metal thin film.

[0003] As a method for forming a conductive circuit in place of the etching method, a printing method using conductive ink has been studied. According to the method of printing conductive ink, compared with the etching method, there are no complicated processes, a conductive circuit can be easily formed, productivity is improved, and cost reduction can be achieved. For example, Patent Document 2 discloses a specific conductive ink containing specific conductive fine particles and a specific epoxy resin as a low-temperature treatment type conductive ink capable of forming a high-definition conductive pattern by screen printing. According to screen printing, thickening of the conductive pattern is possible, and reduction of the resistance of the conductive pattern is said to be achievable.

[0004] Further, Patent Document 3 discloses a method for manufacturing a decorative sheet capable of expressing a three-dimensional sense of solidity, in which a laminate having a printed layer printed in a pattern on a transparent resin layer and a laminated sheet having a decorative layer on a base film are thermocompression bonded to make the decorative layer have a concavo-convex shape along the pattern of the printed layer. [Prior art documents] [Patent Documents]

[0005] [Patent Document 1] Japanese Patent Publication No. 2012-11691 [Patent Document 2] Japanese Patent Publication No. 2011-252140 [Patent Document 3] Japanese Patent Publication No. 2007-296848 [Overview of the Initiative] [Problems that the invention aims to solve]

[0006] According to the method described in Patent Document 1, a conductor can be easily provided on the surface of a molded body. On the other hand, there is a growing demand to form conductive circuits on the surfaces of substrates of various shapes, such as substrates with uneven or curved surfaces. When forming a conductive circuit by laminating a film having a conductive layer onto such a substrate surface, the film needs to be deformed to match the surface shape of the substrate. When the film is deformed, a large tensile force may be generated in parts of the conductive layer. This tensile force can cause the conductive layer to break, leading to a decrease in conductivity. Furthermore, when forming a conductive circuit on a substrate with such uneven or curved surfaces, it is necessary to deform the film having the conductive layer, or to integrate the film and the substrate simultaneously with the deformation. In this integration process, stress is applied to the conductive circuit due to friction with the plastic substrate at high temperatures. This high-temperature stress can also cause the conductive layer to break, leading to a decrease in conductivity.

[0007] This invention has been made in view of the above circumstances, and aims to provide a conductive composition for molded films that can produce molded films in which the decrease in conductivity due to tensile force and stress under high temperature is suppressed, a molded film in which the decrease in conductivity due to tensile force and stress under high temperature is suppressed, and a molded article with excellent conductivity and a method for manufacturing the same. [Means for solving the problem]

[0008] The conductive composition for molded films related to this implementation is: A conductive composition for manufacturing a molded film for forming a conductive layer on a substrate surface having an uneven surface or a three-dimensional curved surface, It contains a resin (A), conductive fine particles (B), and a solvent (C), The resin (A) is one of the group consisting of polyester resin, polyurethane resin, polyamide resin, and polycarbonate resin, and includes resin (A1) which contains constituent units derived from a trifunctional monomer or a tetrafunctional monomer.

[0009] In one embodiment of the conductive composition for molded films described herein, the total content of constituent units derived from trifunctional monomers and tetrafunctional monomers is 0.1% to 15% by mass in the resin (A1).

[0010] In one embodiment of the conductive composition for molded films of this invention, the resin (A1) is a resin having hydroxyl groups or amino groups.

[0011] One embodiment of the conductive composition for molded films of this embodiment comprises one or more conductive fine particles selected from silver powder, copper powder, silver-coated powder, copper alloy powder, conductive oxide powder, and carbon fine particles.

[0012] In one embodiment of the conductive composition for molded films described herein, the ratio of resin (A) in the solid content of the conductive composition is 8 to 40% by weight.

[0013] One embodiment of the conductive composition for molded films described herein further comprises a crosslinking agent (D).

[0014] In one embodiment of the conductive composition for molded films of this invention, the crosslinking agent (D) is a trifunctional blocked isocyanate crosslinking agent.

[0015] The molded film relating to this implementation is a molded film having a conductive layer on a base film, The conductive layer is a cured product of the conductive composition for the formed film of the present embodiment.

[0016] One embodiment of the formed film of the present embodiment is a formed film having a decorative layer and a conductive layer on a base film, The conductive layer is a cured product of the conductive composition for the formed film of the present embodiment.

[0017] In one embodiment of the formed film of the present embodiment, the base film is a film selected from polycarbonate, polymethyl methacrylate, polypropylene, and polyethylene terephthalate, or a laminated film thereof.

[0018] The molded body according to the present embodiment is a molded body in which a conductive layer is laminated on a base material, The conductive layer is a cured product of the conductive composition for the formed film of the present embodiment.

[0019] The first manufacturing method of the molded body according to the present embodiment includes a step of manufacturing a formed film by printing the conductive composition for the formed film of the present embodiment on a base film and drying it, A step of disposing the formed film on a base material, A step of integrating the formed film and the base material by an overlay molding method.

[0020] The second manufacturing method of the molded body according to the present embodiment includes a step of manufacturing a formed film by printing the conductive composition for the formed film of the present embodiment on a base film and drying it, A step of forming the formed film into a predetermined shape, A step of disposing the formed film after forming in a mold for injection molding, A step of molding a base material by injection molding and integrating the formed film and the base material.

[0021] A third method for manufacturing a molded article according to this embodiment includes the steps of: printing the conductive composition for molded films according to this embodiment onto a base film and drying it to manufacture a molded film; The process of placing the molded film inside a mold for injection molding, The process includes molding a substrate by injection molding and transferring a conductive layer in the molded film to the substrate. [Effects of the Invention]

[0022] According to the present invention, it is possible to provide a conductive composition for molded films that can produce molded films in which the decrease in conductivity due to tensile force and stress at high temperatures is suppressed, a molded film in which the decrease in conductivity due to tensile force and stress at high temperatures is suppressed, and a molded article with excellent conductivity and a method for manufacturing the same. [Brief explanation of the drawing]

[0023] [Figure 1] This is a schematic cross-sectional view showing an example of a molded film used in this implementation. [Figure 2] This is a schematic cross-sectional view showing another example of the molded film used in this implementation. [Figure 3] This is a schematic process diagram showing an example of a first method for manufacturing a molded product. [Figure 4] This is a schematic process diagram showing another example of a second method for manufacturing a molded product. [Figure 5] This is a schematic process diagram illustrating another example of a third method for manufacturing a molded product. [Modes for carrying out the invention]

[0024] The conductive composition for molded films, molded films, molded articles, and their manufacturing methods related to this implementation will be described in detail below. In this implementation, the term "cured material" includes not only materials that have hardened through chemical reactions, but also materials that have hardened without chemical reactions, such as materials that have hardened due to the evaporation of a solvent.

[0025] [Conductive composition for molded films] It contains a resin (A), conductive fine particles (B), and a solvent (C), The resin (A) comprises one of the following: polyester resin, polyurethane resin, polyamide resin, and polycarbonate resin. The resin (A) contains constituent units derived from a trifunctional monomer or a tetrafunctional monomer.

[0026] The inventors investigated screen-printable conductive compositions in order to manufacture molded films that are applicable to non-flat substrate surfaces and have process suitability for integration with plastic substrates. In order to apply them to the manufacture of molded films, various adjustments were made to the resin structure, conductive fine particles, and solvents. The inventors found that the type of solvent included in the conductive composition, particularly the use of a solvent with a specific aromatic alcohol structure, affected the frequency of crack formation when the resulting molded film was subjected to tensile deformation at high temperatures. Furthermore, they discovered that the glass transition temperature and main chain structure of the resin combined with the mixed solvent affected the frequency of printing defects such as chipping and streaking during high-speed printing, as well as the magnitude of the change in resistance during tensile deformation, especially when the degree of deformation is large at high temperatures. Based on these findings, the inventors conducted investigations and found that when a conductive composition containing no solvent with a specific aromatic alcohol structure is printed and heat-dried on a resin film, significant deterioration of the conductivity of the conductive layer pattern and crack formation of the conductive layer occur when the molded film is deformed by tensile stress at a high temperature corresponding to its softening point. Furthermore, it became clear that the frequency of printing defects such as chipping and smudging increases significantly when the printing speed of the conductive composition is increased. The same was true when a conductive layer was provided on a decorative layer.

[0027] Even molded films with conductive layers that exhibit cracking or significant resistance changes when deformed by high-temperature tension did not pose a problem when used as flat film circuit boards or when used in a bent state on a two-dimensional curved surface. However, when used as a molded film that conforms to and integrates with the shape of a non-flat substrate surface, such as an uneven or three-dimensional curved surface, the molded film will deform. Therefore, it is predicted that the conductive layer will not be able to follow the deformation of the resin film, resulting in delamination or disconnection from the base film, and thus a decrease in the conductivity of the conductive layer. In this invention, the terms "uneven surface" and "three-dimensional curved surface" refer not only to surfaces with gently curved cross-sections, but also to all three-dimensional surfaces having sharp angles or rectangular shapes. In other words, they refer to three-dimensional shapes that cannot be created by simply deforming a plane without stretching or compressing it, such as hemispherical, conical, cylindrical, and rectangular prism shapes. Furthermore, if a certain three-dimensional shape has elements of both a plane or two-dimensional curved surface and a three-dimensional curved surface within a continuous three-dimensional surface, for example, a three-dimensional shape in which one or more partial hemispherical shapes are combined with a plane shape, is considered a three-dimensional curved surface because it is a three-dimensional shape that cannot be created by deforming a plane without stretching or compressing it as a whole. In short, the uneven surfaces and three-dimensional curved surfaces in this invention cannot be realized by bending flexible substrates, etc., and are shapes that can be realized, for example, by shaping a moldable film by three-dimensional molding under heating.

[0028] Based on these findings, the inventors conducted diligent studies and found that when a molded film on which conductive wiring is formed is contained in a resin having a structure composed of specific constituent monomers, the change in wiring resistance value that occurs when the film is pulled at a particularly high deformation rate with a large degree of deformation is reduced. Furthermore, even when a strong impact is applied to the molded body in which the conductive wiring is molded and integrated, the occurrence of wiring breakage is highly suppressed. As a result, the inventors have completed the present invention. In other words, the conductive composition for molded films of the present invention, by using a resin having a structure composed of specific constituent monomers, conductive fine particles, and a solvent in combination, allows for the easy production of molded films having a thick conductive layer with excellent conductivity by screen printing or the like. Furthermore, molded films produced using this conductive composition for molded films exhibit suppressed degradation of conductivity even when used on non-flat substrate surfaces. Moreover, by using this molded film, it is possible to obtain a molded article with high impact resistance in which conductive circuits are formed on any surface, such as steep uneven surfaces or curved surfaces, on a substrate made of three-dimensional plastic with practical strength.

[0029] The conductive composition for molded films described in this embodiment contains at least a resin (A), conductive fine particles (B), and a solvent (C), and may contain other components as needed. The components of such a conductive composition for molded films will be described below.

[0030] <Resin (A)> The conductive composition in this embodiment contains a binder resin (A) to provide film-forming properties and adhesion to the base film or decorative layer. In addition, in this embodiment, the inclusion of resin (A) provides flexibility to the conductive layer. Therefore, the inclusion of resin (A) suppresses wire breakage of the conductive layer when stretched.

[0031] The resin (A) used in the conductive composition of this embodiment is one of the group consisting of polyester resin, polyurethane resin, polyamide resin, and polycarbonate resin, and contains as an essential component a resin (A1) which includes constituent units derived from a trifunctional monomer or a tetrafunctional monomer. The resin (A1) contains structural units derived from trifunctional monomers or tetrafunctional monomers, resulting in a high density and planar arrangement of ester bonds, urethane bonds, amide bonds, and carbonate bonds near the branched structures derived from these trifunctional monomers or tetrafunctional monomers. This exhibits strong adsorption to the conductive fine particles (B), described later, thus suppressing the formation of voids that would cause wire breakage during tensile stress in molding. Furthermore, when used in combination with the crosslinking agent (D), described later, an even tougher resin crosslinking network is formed, providing even greater resistance to wire breakage during molding.

[0032] The polyester resin used as resin (A1) in this implementation is a resin obtained by copolymerizing a diol monomer having two hydroxyl groups in one molecule, a dicarboxylic acid monomer having two carboxyl groups in one molecule, and a trifunctional or tetrafunctional monomer having a total of 3 to 4 hydroxyl groups or carboxyl groups in one molecule. Examples of diol monomers having two hydroxyl groups in one molecule include, but are not limited to, aliphatic diols such as ethylene glycol, propylene glycol, 1,3-butylene glycol, 1,4-butylene glycol, neopentyl glycol, 3-methyl-1,5-pentanediol, 1,6-hexanediol, and nonanediol, alicyclic diols such as 1,4-cyclohexanedimethanol, and aromatic diols such as O,O'-bis-(2-hydroxyethyl)bisphenol A. Furthermore, these diol monomers may be subjected to multi-step copolymerization, such as prepolymerizing a prepolymer diol by copolymerizing it with a dicarboxylic acid monomer (described later), or with an alkylene oxide such as ethylene oxide or propylene oxide, or a cyclic monomer such as ε-caprolactone or ε-caprolactam, and then polymerizing it with a dicarboxylic acid. Examples of dicarboxylic acids having two carboxyl groups in one molecule include aliphatic dicarboxylic acids such as succinic acid, adipic acid, and sebacic acid; alicyclic dicarboxylic acids such as hexahydroterephthalic acid and dimer acid; and aromatic dicarboxylic acids such as phthalic acid, isophthalic acid, and terephthalic acid. Dicarboxylic acid esters such as methyl esters and ethyl esters of these can also be suitably used, but are not limited to these. Alternatively, prepolymerized dicarboxylic acids may be synthesized in advance by copolymerizing these dicarboxylic acid monomers with cyclic monomers such as ε-caprolactone and ε-caprolactam, and then subjected to multi-step copolymerization. Examples of trifunctional or tetrafunctional monomers having a total of 3 to 4 hydroxyl groups and / or carboxyl groups in one molecule include, but are not limited to, trimethylolpropane, glycerin, pentaerythritol, trimellitic acid, hexahydrotrimellitic acid, pyromellitic acid, hexahydropyromellitic acid, trimer acid, 1,2,3-tricarboxylpropane, 2,2-dimethylolpropionic acid, 2,2-dimethylolbutyric acid, and citric acid.

[0033] Furthermore, polyester resins used as resin (A1) in this embodiment do not include those containing a total of 20% by mass or more of monofunctional monomers having only one of either a hydroxyl group or a carboxyl group per molecule, and oils and fats (such as coconut oil and linseed oil, which are triglycerides composed of glycerin and fatty acids) as constituent monomers (so-called alkyd resins), as they do not exhibit suitable properties for use as resin (A1) in this embodiment.

[0034] The urethane resin used as resin (A1) in this implementation is a resin obtained by copolymerizing a diol monomer having two hydroxyl groups in one molecule, a diisocyanate monomer having two isocyanate groups in one molecule, and a trifunctional or tetrafunctional monomer having 3 to 4 of either hydroxyl groups or isocyanate groups in one molecule. Examples of diol monomers having two hydroxyl groups in one molecule include, but are not limited to, the various diols listed as examples of raw materials for polyester synthesis. Examples of diisocyanates having two isocyanate groups in one molecule include, but are not limited to, aliphatic diisocyanates such as hexamethylene diisocyanate, alicyclic diisocyanates such as isophorone diisocyanate and hexahydro-1,3-xylylene diisocyanate, and aromatic diisocyanates such as 1,3-tolylene diisocyanate, 1,4-tolylene diisocyanate, diphenylmethane diisocyanate, 1,3-xylylene diisocyanate, C,C,C',C',-tetramethyl-1,3-xylylene diisocyanate and 1,6-naphthyl diisocyanate. Alternatively, a prepolymer diisocyanate may be synthesized in advance by copolymerizing these diisocyanate monomers with the aforementioned diol monomers and subjected to multi-step copolymerization. Examples of trifunctional or tetrafunctional monomers having 3 to 4 hydroxyl groups or isocyanate groups in a single molecule include, but are not limited to, trimethylolpropane, glycerin, pentaerythritol, and the isocyanurates, allophanates, and biuretes obtained by triperizing or tetramerizing each of the diisocyanates.

[0035] The polyamide resin used as resin (A1) in this implementation is a resin obtained by copolymerizing a diamine monomer having two amino groups in one molecule, a dicarboxylic acid monomer having two carboxyl groups in one molecule, and a trifunctional or tetrafunctional monomer having a total of 3 to 4 amino groups and / or carboxyl groups in one molecule. Examples of diamine monomers having two amino groups in one molecule include, but are not limited to, 1,3-propanediamine, 1,4-butanediamine, 1,4-piperazine, dimeramine, and 1,3-xylylenediamine. Alternatively, an alkylene oxide such as ethylene oxide or propylene oxide may be subjected to multi-step copolymerization via a polyalkylene oxide diamine obtained by first ring-opening polymerization and then converting the terminal hydroxyl groups to amino groups. Examples of dicarboxylic acids having two carboxyl groups in one molecule include, but are not limited to, the various dicarboxylic acids listed as examples of raw materials for polyester synthesis. Examples of trifunctional or tetrafunctional monomers having a total of 3 to 4 amino groups or carboxyl groups in one molecule include, but are not limited to, the various trifunctional or tetrafunctional monomers listed as examples of raw materials for polyester synthesis.

[0036] The polycarbonate resin used as resin (A1) in this implementation is a resin obtained by copolymerizing a diol monomer having two hydroxyl groups in one molecule, a carbonate monomer having one carbonate group in one molecule, and a trifunctional or tetrafunctional monomer having three to four hydroxyl groups in one molecule. Examples of diol monomers having two hydroxyl groups in one molecule include, but are not limited to, the various diols listed as examples of raw materials for polyester synthesis. Examples of carbonate monomers having one carbonate group in a single molecule include, but are not limited to, dimethyl carbonate, diphenyl carbonate, ethylene carbonate, and propylene carbonate. Examples of trifunctional or tetrafunctional monomers having 3 to 4 hydroxyl groups in one molecule include, but are not limited to, trimethylolpropane, glycerin, and pentaerythritol.

[0037] The total content of constituent units derived from trifunctional monomers and tetrafunctional monomers in resin (A) is preferably 0.1% to 15% by mass, and more preferably 0.5% to 10% by mass. Among these, the total content of constituent units derived from trifunctional monomers and tetrafunctional monomers in resin (A1) is preferably 0.2% to 15.5% by mass, and more preferably 0.5% to 10% by mass. If the total content of constituent units derived from trifunctional monomers and tetrafunctional monomers is equal to or greater than the lower limit, the density of molecular structures in which ester bonds, urethane bonds, amide bonds, and carbonate bonds are densely and planarly arranged near the branched structures derived from trifunctional monomers or tetrafunctional monomers increases. This exhibits strong adsorption to conductive fine particles (B) described later, and is preferable because it can suppress the generation of voids that cause disconnections between the particles during tensile stress during molding. Furthermore, when used in combination with the crosslinking agent (D) described later, it is preferable because it can form a resin crosslinked network with excellent heat resistance and elongation, and has excellent resistance to molding processes with high deformation rates. It is preferable that the total content of constituent units derived from trifunctional monomers and tetrafunctional monomers is below the above upper limit, as this allows for excellent resistance to the molding process while maintaining the good solubility and toughness of the resin (A) in solvent (C). It is also preferable that, when used in combination with a crosslinking agent (D), it is possible to achieve both high heat elongation resistance, toughness, and high limit elongation.

[0038] It is also preferable to pre-synthesize a prepolymer containing constituent units derived from a trifunctional monomer or tetrafunctional monomer by copolymerizing a trifunctional monomer and / or tetrafunctional monomer with a difunctional monomer, alkylene oxides such as ethylene oxide and propylene oxide, or cyclic monomers such as ε-caprolactone and ε-caprolactam, and then synthesize resin (A1) through multi-step copolymerization, such as further polymerization of this prepolymer with a trifunctional monomer or tetrafunctional monomer or a difunctional monomer. However, in this case, the total content of constituent units derived from trifunctional monomers and tetrafunctional monomers in resin (A1) shall be the mass ratio of the smallest trifunctional monomer and tetrafunctional monomer-derived constituent units in resin (A1), regardless of whether the synthesis is one-step or multi-step, and shall not be the entire prepolymer containing repeating structures derived from difunctional monomers.

[0039] In calculating the mass fractions of the constituent units derived from the trifunctional monomers and tetrafunctional monomers, for polyester resins, the mass of the carbonyl group (-C(=O)-) in the ester bond is assigned to the carboxyl group monomer, and the mass of the single bonded oxygen atom (-O-) is assigned to the hydroxyl group monomer. Similarly, for urethane resins, the mass of the imino group (-NH-) and carbonyl group (-C(=O)-) in the urethane bond is assigned to the isocyanate group monomer, and the mass of the single bonded oxygen atom (-O-) is assigned to the hydroxyl group monomer. For polyamide resins, the mass of the carbonyl group (-C(=O)-) in the amide bond is assigned to the carboxyl group monomer, and the mass of the imino group (-NH-) is assigned to the amino group monomer. For polycarbonate resins, the mass of the carbonyl group (-C(=O)-) in the carbonate bond is assigned to the carbonate group monomer, and the mass of the single bonded oxygen atom (-O-) is assigned to the hydroxyl group monomer.

[0040] In this embodiment, the resin (A1) preferably has two or more substituents selected from hydroxyl groups, amino groups, carboxyl groups, and acid anhydride groups in one molecule, and it is particularly preferable that it has two or more hydroxyl groups or amino groups in one molecule. In this case, by combining it with the crosslinking agent (D) described later, the resin (A1) can be crosslinked in three dimensions, and particularly high high-speed elongation resistance can be obtained under the high-temperature conditions of film molding of the conductive layer.

[0041] If resin (A1) has a functional group selected from a hydroxyl group, an amino group, a carboxyl group, and an acid anhydride group, its functional value is preferably 1 mg KOH / g or more and 400 mg KOH / g or less, and preferably 2 mg KOH / g or more and 350 mg KOH / g or less. The details of the method for calculating the functional value will be explained in the examples below. If resin (A1) has multiple types of functional groups, the functional value is the sum of those groups. For example, if resin (A1) has both a hydroxyl group and a carboxyl group, the functional value represents the sum of the hydroxyl value and the acid value of resin (A1).

[0042] From the viewpoint of maintaining conductivity during molding tension and ensuring resistance to frictional stress with the plastic substrate at high temperatures during the integration process with the plastic substrate, the glass transition temperature (Tg) of resin (A) is preferably 0°C to 130°C, and more preferably 5°C to 120°C. Similarly, if resin (A) has multiple glass transition points, it is preferable that none of the glass transition points are below 0°C.

[0043] In this implementation, resin (A1) may be synthesized and used by the examples described later or by other known methods, or a commercially available product that satisfies the above conditions may be used. Resin (A1) can be used alone or in combination of two or more types, and resin (A) can also be used in combination with resin (A1) and other resins (A2) that do not fall under resin (A1). When resin (A1) and other resins (A2) are used in combination, it is preferable that resin (A1) accounts for 20 to 100% by mass of the total amount of resin (A1) and other resins (A2), and it is even more preferable that resin (A1) accounts for 30 to 100% by mass.

[0044] The content of resin (A) in the conductive composition of this embodiment is not particularly limited and can be adjusted as appropriate depending on the application, but it is preferably 8% by mass or more and 40% by mass or less, and more preferably 10% by mass or more and 30% by mass or less, relative to the total amount of solids contained in the conductive composition. If the content of resin (A) is above the lower limit, film-forming properties and adhesion to the base film, etc., can be improved, and flexibility can be imparted to the conductive layer. If the content of resin (A) is below the upper limit, the content of conductive fine particles (B) can be relatively increased, and a conductive layer with excellent conductivity can be formed.

[0045] <Conductive fine particles (B)> Conductive microparticles (B) exhibit conductivity through contact between multiple conductive microparticles within a conductive layer. In this embodiment, conductive microparticles are appropriately selected and used from those that can be made conductive without heating at high temperatures. Examples of conductive nanoparticles used in this implementation include metal nanoparticles, carbon nanoparticles, and conductive oxide nanoparticles. Examples of metal nanoparticles include elemental metal powders such as gold, silver, copper, nickel, chromium, palladium, rhodium, ruthenium, indium, aluminum, tungsten, molarbutene, and platinum, as well as alloy powders such as copper-nickel alloys, silver-palladium alloys, copper-tin alloys, silver-copper alloys, and copper-manganese alloys, and metal coated powders in which the surface of the elemental metal powders or alloy powders is coated with silver or the like. Examples of carbon nanoparticles include carbon black, graphite, and carbon nanotubes. Examples of conductive oxide nanoparticles include silver oxide, indium oxide, tin oxide, zinc oxide, and ruthenium oxide.

[0046] In this implementation, it is preferable to include one or more conductive fine particles selected from silver powder, copper powder, silver-coated powder, copper alloy powder, conductive oxide powder, and carbon fine particles. By using these conductive fine particles (B), a conductive layer with excellent conductivity can be formed without sintering, and a conductive layer with excellent stretchability and conductivity retention performance when molded into a three-dimensional shape as a molded film as described later can be formed.

[0047] The shape of the conductive fine particles (B) is not particularly limited, and spherical, flake-shaped, or chain-aggregate-shaped particles can be used as appropriate. However, from the viewpoint of maintaining printability and conductivity during molding and tension, flake-shaped or chain-aggregate-shaped particles are particularly preferred. In this invention, "spherical" refers to all particles with a low aspect ratio, such as perfect spheres, oval shapes, flattened spheres, pebbles, and polyhedrons, specifically those with an aspect ratio of 1 to 2. In this invention, "flake-like" refers to all flattened two-dimensional planar shapes, such as flake-like, scale-like, plate-like, flattened, and sheet-like, with those having an aspect ratio of 3 to 500 being particularly preferred. Furthermore, in this invention, "chain-aggregated" refers to all amorphous shapes in which multiple spherical conductive fine particles are directly fused and bonded together.

[0048] The D50 particle size of conductive fine particles (B) is not particularly limited, but from the viewpoint of maintaining dispersibility and printability in the conductive composition, maintaining conductivity during molding, and resistance to injection molding processes by molten resin or friction resistance at high temperatures to molded resin, it is preferably 0.2 μm or more and less than 30 μm, and particularly preferably 0.7 μm or more and less than 15 μm. In this implementation, the average particle size of conductive fine particles (B) was calculated as follows. In accordance with the laser diffraction and scattering method described in JIS M8511 (2014), a laser diffraction and scattering particle size distribution analyzer (Nikkiso Co., Ltd.: Microtrac 9220FRA) was used. An appropriate amount of conductive fine particles (B) was added to an aqueous solution containing 0.5 volume% of the commercially available surfactant polyoxyethylene octylphenyl ether (Roche Diagnostics K.K.: Triton X-100) as a dispersant, and after irradiating with 40 W ultrasonic waves for 180 seconds while stirring, the measurement was performed. The obtained median diameter (D50) value was taken as the average particle size of conductive fine particles (B).

[0049] In this implementation, conductive fine particles (B) can be used individually or in combination of two or more types. The content of conductive fine particles (B) in the conductive composition of this embodiment is not particularly limited and can be adjusted as appropriate depending on the application, but it is preferably 50% to 90% by mass, and preferably 55% to 85% by mass, relative to the total amount of solids contained in the conductive composition. If the content of conductive fine particles (B) is above the lower limit, a conductive layer with excellent conductivity can be formed. If the content of conductive fine particles (B) is below the upper limit, the content of resin (A) can be increased, improving film-forming properties and adhesion to base films, and also imparting flexibility to the conductive layer.

[0050] <Solvent (C)> In this embodiment, solvent (C) is included to dissolve resin (A), impart fluidity and printability, and to adjust the spread and entanglement of molecular chains within the resin (A) composition. Furthermore, in this embodiment, by including solvent (C), the spread of the molecular chains is adjusted and wettability is provided for printing on the base film, thereby improving the patterning accuracy during printing.

[0051] The solvent (C) of the present invention can be used without particular limitation from publicly known and publicly available solvents, as long as it can dissolve the resin (A). Solvent (C) can be used alone or in combination of two or more. Furthermore, even if it is a solid at room temperature on its own, it can be used without any problems as a liquid when mixed with solvents of other structures. In addition, solvent (C) is particularly preferably a solvent with a boiling point of 180°C or higher and 270°C or lower. Examples of solvents include glycol esters such as 2-ethoxy(2-ethoxy)ethyl acetate and 2-ethoxy(2-ethoxy)butyl acetate, glycol ethers such as 2-ethoxy(2-ethoxy)ethanol and 2-butoxy(2-ethoxy)ethanol and diethylene glycol diethyl ether, but is not particularly limited.

[0052] <Optional ingredients> The conductive composition of the present invention may optionally contain other components. Examples of such other components include the crosslinking agent (D) described later, as well as dispersants, friction-resistant agents, infrared absorbers, ultraviolet absorbers, fragrances, antioxidants, organic pigments, inorganic pigments, defoamers, silane coupling agents, plasticizers, flame retardants, and humectants.

[0053] <Crosslinking agent (D)>

[0054] In this embodiment, a crosslinking agent (D) may be additionally used to crosslink the resin (A). The crosslinking agent (D) can be appropriately selected from those having two or more reactive functional groups in one molecule that can form crosslinks with the reactive functional groups of the resin (A). Examples of such reactive functional groups include epoxy groups, isocyanate groups, blocked isocyanate groups, alkyloxyamino groups, aziridinyl groups, oxetanyl groups, carbodiimide groups, and β-hydroxyalkylamide groups. The crosslinking agent (D) is preferably used in an amount of 0.05 parts by mass or more and 30 parts by mass or less per 100 parts by mass of resin (A), and more preferably in an amount of 0.3 parts by mass or more and 25 parts by mass or less.

[0055] Furthermore, in this embodiment, it is preferable that the resin (A) has two or more first reactive functional groups selected from hydroxyl groups or amino groups in one molecule, and it is particularly preferable to select and combine a blocked isocyanate as the crosslinking agent (D). Blocked isocyanates are not particularly limited and can be any isocyanate compounds in which the isocyanate group of a bifunctional isocyanate, such as hexamethylene diisocyanate, tolylene diisocyanate, xylylene diisocyanate, tetramethylxylylene diisocyanate, isophorone diisocyanate, or a bifunctional or more isocyanate, such as an allophanate, biuret, adduct, prepolymer, or isocyanurate thereof, is protected (blocked) with ε-caprolactam, MEK oxime, etc. Specifically, examples include isocyanate compounds in which the isocyanate group of the above isocyanate compounds is blocked with ε-caprolactam, MEK oxime, cyclohexanone oxime, pyrazole, 3,5-dimethylpyrazole, diisopropylamine, diethyl malonate, ethyl acetoethyl, phenol, etc. It is also preferable to use a reaction catalyst that has the effect of promoting the reaction between these crosslinking agents (D) and resin (A). Any known reaction catalyst can be used without particular limitation. By using this combination, the unique crosslinking point structure generated by crosslinking with the resin (A) and the multi-point adsorption point structure with the conductive particles are increased. As a result, a conductive layer with particularly excellent toughness and superior ability to suppress the generation of voids that can occur between conductive fine particles (B) in the coating film at high temperatures, which can lead to wire breakage, can be obtained.

[0056] <Method for producing conductive compositions> The method for producing the conductive composition of this embodiment is any method of dissolving or dispersing the resin (A), conductive fine particles (B), wire-shaped fine particles (C), and other components used as necessary, and can be produced by mixing them using known mixing methods.

[0057] [Molded film] The molded film of this embodiment is a molded film having a conductive layer on a base film, The conductive layer is characterized in that it is a cured product of the conductive composition for molded films. According to the molded film of this invention, a molded body can be obtained in which a conductive circuit is formed on any substrate surface, such as an uneven surface or a curved surface. According to the molded film of this invention, a molded body can be obtained in which a conductive circuit is formed on any substrate surface, such as an uneven surface or a curved surface. The layer structure of the molded film in this embodiment will be explained with reference to Figures 1 and 2. Figures 1 and 2 are schematic cross-sectional views showing an example of the molded film in this embodiment. The molded film 10 shown in the example in Figure 1 comprises a conductive layer 2 on a base film 1. The conductive layer 2 may be formed over the entire surface of the base film 1, or it may be formed in a desired pattern as in the example in Figure 1. The molded film 10 shown in the example in Figure 2 has a decorative layer 3 on a base film 1, and a conductive layer 2 on the decorative layer 3. Also, as shown in the example in Figure 2, the molded film 10 may have electronic components 4 and pins 5 for connecting to an extraction circuit on the conductive layer 2. Furthermore, although not shown in the figures, a resin layer may be provided on the conductive layer 2 or on the electronic component 4 to protect the conductive layer or electronic component, and this resin layer may be an adhesive layer or bonding layer to improve adhesion with the substrate, as described later. Furthermore, although not shown in the figures, if the molded film 10 of this embodiment includes a decorative layer 3, in addition to the example in Figure 2, the base film 1 may have a decorative layer 3 on one side and a conductive layer 2 on the other side. The molded film in this embodiment comprises at least a base film and a conductive layer, and may have other layers as needed. The layers of such a molded film will be described below.

[0058] <Base film> In this implementation, the base film can be appropriately selected from among those having flexibility and stretchability sufficient to conform to the shape of the substrate surface under the molding temperature conditions during substrate formation, and it is preferable to select it according to the application of the molded article and the manufacturing method of the molded article. For example, when employing the overlay molding method or the film insert method described later as a method for manufacturing molded articles, the base film remains in the molded article, and therefore, the base film can be selected considering its function as a protective layer for the conductive layer. On the other hand, when employing an in-mold transfer method or the like described later as a method for manufacturing the molded article, it is preferable to select a base film with release properties.

[0059] The base film can be appropriately selected from the above viewpoints, and may be, for example, films of polycarbonate, polymethyl methacrylate, polyethylene terephthalate, polystyrene, polyimide, polyamide, polyethersulfone, polyethylene naphthalate, polybutylene terephthalate, polyvinyl chloride, polyethylene, polypropylene, cycloolefin polymer, ABS (acrylonitrile-butadiene-styrene copolymer resin), AES (acrylonitrile-ethylene-styrene copolymer resin), Kydex (acrylic-modified vinyl chloride resin), modified polyphenylene ether, and polymer alloys made of two or more of these resins, or laminated films thereof. Among these, films selected from polycarbonate, polymethyl methacrylate, polypropylene, and polyethylene terephthalate, or laminated films thereof, are preferred. Among the laminated films, a laminated film of polycarbonate and polymethyl methacrylate is preferred. The method for manufacturing a laminated film of polycarbonate and polymethyl methacrylate is not particularly limited. A polycarbonate film and a polymethyl methacrylate film may be laminated together, or the polycarbonate and polymethyl methacrylate may be co-extruded to form a laminated film. Furthermore, it is preferable that the surface of these base films is subjected to modification treatments such as corona treatment.

[0060] Furthermore, if necessary, an anchor coat layer may be provided on the base film for purposes such as improving the printability of the conductive composition, and the conductive composition may be printed on the anchor coat layer. The anchor coat layer is not particularly limited as long as it has good adhesion to the base film and to the conductive composition and follows the film during molding, and organic fillers such as resin beads and inorganic fillers such as metal oxides may also be added as needed. The method for providing the anchor coat layer is not particularly limited and can be obtained by applying, drying, and curing using conventionally known coating methods. Furthermore, if necessary, a hard coat layer may be provided on the base film to prevent scratching of the molded surface, and a conductive composition and, if necessary, a decorative layer may be printed on the opposite side. The hard coat layer is not particularly limited as long as it has good adhesion to the base film, good surface hardness, and conforms to the film during molding. Organic fillers such as resin beads and inorganic fillers such as metal oxides may also be added as necessary. The method for providing the hard coat layer is not particularly limited and can be obtained by applying, drying, and curing using conventionally known coating methods.

[0061] Furthermore, if the molded film in this embodiment has a decorative layer, it is preferable to select a transparent base film.

[0062] The thickness of the base film is not particularly limited, but for example, it can be 10 μm or more and 500 μm or less, and preferably 20 μm or more and 450 μm or less.

[0063] <Conductive layer> In the molded film of this embodiment, the conductive layer is a cured product of the conductive composition. The conductive layer may be a patterned conductive layer or a solid-coated conductive layer. The method for forming the conductive layer is not particularly limited, but in this embodiment, it is preferable to form it by screen printing, pad printing, stencil printing, screen offset printing, dispenser printing, gravure offset printing, inverted offset printing, or microcontact printing, and it is more preferable to form it by screen printing. In screen printing, it is preferable to use a screen with a fine mesh, particularly one with a mesh of about 300 to 650 mesh, in order to accommodate the high resolution of conductive circuit patterns. In this case, the open area of ​​the screen is preferably about 20 to 50%. The screen wire diameter is preferably about 10 to 70 μm. Types of screens include polyester screens, combination screens, metal screens, and nylon screens. Furthermore, high-tensile stainless steel screens can be used when printing highly viscous paste-like materials. The squeegee for screen printing can be round, rectangular, or square in shape, and a polished squeegee can also be used to reduce the attack angle (the angle between the screen and the squeegee during printing). Other printing conditions can be appropriately designed based on conventionally known conditions.

[0064] The conductive composition is printed by screen printing, then heated to dry and undergo a crosslinking reaction for curing. To ensure sufficient volatilization of the solvent and crosslinking reaction, the heating temperature is preferably 80-230°C and the heating time is preferably 10-120 minutes. This allows for the acquisition of a patterned conductive layer. The pattern of the conductive layer is not particularly limited, but may include, for example, solid patterns or open patterns of straight lines, curves, meshes, or partial squares, circles, or diamond shapes, or any combination thereof, or the entire conductive layer may be a solid pattern, and is not limited as long as the conductive layer functions as a conductive circuit or as part of a conductive circuit. The patterned conductive layer may be provided with an insulating layer to cover the conductive pattern, if necessary. The insulating layer is not particularly limited, and known insulating layers can be used.

[0065] The thickness of the conductive layer can be adjusted as appropriate according to the required conductivity, and is not particularly limited, but for example it can be 0.5 μm or more and 20 μm or less, and preferably 1 μm or more and 15 μm or less.

[0066] <Decorative layer> The molded film in this embodiment may have a decorative layer, from the viewpoint of the aesthetic appeal of the resulting molded product. The decorative layer may be a layer with a single color, or it may have any pattern applied to it. The decorative layer can be formed, for example, by preparing a decorative ink containing a colorant, a resin, and a solvent, and then applying the decorative ink to a base film using known printing means. The colorant can be appropriately selected from known pigments and dyes. Furthermore, it is preferable to appropriately select the resin from those similar to resin (A) in the conductive composition of this embodiment. The thickness of the decorative layer is not particularly limited, but can be, for example, 0.5 μm or more and 10 μm or less, and preferably 1 μm or more and 5 μm or less.

[0067] [Molded body] The molded article of this embodiment is a molded article having at least a conductive layer laminated on a substrate, wherein the conductive layer is a cured product of the conductive composition for molded films described in any one of claims 1 to 5. Since the molded article of this embodiment is formed from a molded film using the conductive composition for molded films of this embodiment, it becomes a molded article in which conductive circuits are formed on any surface, such as uneven surfaces or curved surfaces. Three embodiments of the method for manufacturing the molded article of this embodiment will be described below. Note that the molded article of this embodiment may be manufactured using the conductive composition of this embodiment, and is not limited to these methods.

[0068] <First manufacturing method> The first method for manufacturing a molded article according to this embodiment includes the steps of: printing the conductive composition for molded film according to this embodiment onto a base film and drying it to manufacture a molded film; A step of placing the molded film on the substrate, The process includes a step of integrating the molded film and the substrate by an overlay molding method. The following explanation will refer to Figure 3, but the method for manufacturing the molded film is as described above, so the explanation will be omitted here.

[0069] Figure 3 is a schematic process diagram showing an example of the first method for manufacturing a molded product. Figures 3(A) to (C) show the molded film 10 and substrate 20 arranged inside the chamber box of a TOM (Three-Dimensional Overlay Method) molding machine, respectively, while the chamber box is omitted in Figures 3(B) and (C). In the first manufacturing method, first, the substrate 20 is placed on the table of the lower chamber box 22. Next, the molding film 10 of this embodiment is passed between the upper chamber box 21 and the lower chamber box 22 and placed on the substrate 20. At this time, the molding film 10 may be positioned so that the conductive layer faces either the substrate 20 side or the side opposite to the substrate 20, and this can be selected depending on the final application of the molded body. Next, the upper and lower chamber boxes are evacuated and the molding film is heated. Next, the substrate 20 is raised by raising the table 15. Next, only the inside of the upper chamber box 21 is opened to the atmosphere (Figure 3(B)). At this time, the molding film is pressurized towards the substrate 16, and the molding film 10 and the substrate 20 are bonded together and integrated (Figure 3(C)). In this way, the molded body 30 can be obtained.

[0070] In the first manufacturing method, the base material 20 can be prepared in advance by any method. In the first manufacturing method, the material of the base material 20 is not particularly limited and may be made of resin or metal.

[0071] In this first manufacturing method, the frictional stress with the base plastic at high temperatures during the integration process with the base material is caused by the frictional stress between the conductive circuit of the molded film and the base material at high temperatures when the molded film in Figure 3(C) is pressed against the base material side 16, and the molded film 10 and the base material 20 are bonded together and integrated. In other words, in this first manufacturing method, the conductive layer is subjected to both tensile stress during molding and frictional stress with the base plastic at high temperatures.

[0072] <Second manufacturing method> The second method for manufacturing a molded article according to this embodiment includes the steps of: printing the conductive composition for molded film according to this embodiment onto a base film and drying it to manufacture a molded film; A step of forming the aforementioned molded film into a predetermined shape, A step of placing the molded film after molding into a mold for injection molding, The process includes molding a substrate by injection molding and integrating the molded film with the substrate. The following explanation will be given with reference to Figure 4. The second manufacturing method is sometimes referred to as the film insert method.

[0073] Figure 4 is a schematic process diagram showing an example of a second method for manufacturing a molded body. In the second manufacturing method, the molded film 10 is pre-formed into a predetermined shape using a mold 11 (Figure 4(A)). The molded film 10 is heated and softened, or while softening, and then molded using the mold 11 by vacuum suction to the mold, compressed air pressing to the mold, or a combination of both (Figure 4(B)). At this time, the molded film 10 may be molded so that the conductive layer faces either the side of the substrate 20 (described later) or the side opposite to the substrate 20, and this is selected according to the final application of the molded body. Next, the molded film 10 is placed in a mold 12 for injection molding (Figures 4(C) to 4(D)). Next, resin is injected 14 from the opening 13 to form the substrate 20, and the molded film 10 and the substrate 20 are integrated to obtain a molded body 30 (Figure 4(E)).

[0074] In the second manufacturing method, the base material 20 does not need to be prepared in advance, and the molding of the base material and integration with the molded film can be performed simultaneously. The material of the base material 20 can be appropriately selected from known resins used for injection molding.

[0075] In this second manufacturing method, the frictional stress with the base plastic at high temperatures during the integration process with the base material is caused by the frictional stress that the conductive layer on the molded film experiences when the resin is injected 14 from the opening 13 in Figure 4(E) to form the base material 20 and when the molded film 10 and the base material 20 are integrated, due to the injection of high-temperature molten resin into the mold. In other words, in this second manufacturing method, the conductive layer is subjected to a load due to tensile stress during molding, and then in a separate process, it is subjected to frictional stress with the base plastic at high temperatures.

[0076] <Third manufacturing method> A third method for manufacturing a molded article according to this embodiment includes the steps of: printing the conductive composition for molded film according to this embodiment onto a base film by screen printing and drying to produce a molded film; The process of placing the molded film inside a mold for injection molding, The process includes molding a substrate by injection molding and transferring a conductive layer in the molded film to the substrate. The following explanation will be given with reference to Figure 5. Note that the third manufacturing method is sometimes called the in-mold transfer method.

[0077] Figure 5 is a schematic process diagram showing an example of a third method for manufacturing a molded body. In the third manufacturing method, a molded film 10 is selected and used as a base film that has release properties. The molded film 10 is placed in an injection mold 12 so that the conductive layer faces the substrate 20, which will be described later (Figure 5(A)). Next, resin is injected 14 from the opening 13 to form the substrate 20, and the molded film 10 and the substrate 20 adhere to each other, and at least the conductive layer is transferred to the substrate 20 (Figure 5(B)), and a molded body 30 is obtained (Figure 5(C)). If the molded film 10 has a decorative layer, both the decorative layer and the conductive layer are transferred.

[0078] In the third manufacturing method, since there is no need to cut the base film, a long base film can be arranged as shown in the example in Figure 5. The material of the substrate 20 can be appropriately selected from known resins used for injection molding.

[0079] In this third manufacturing method, the frictional stress with the base plastic at high temperatures during the integration process with the base material is caused by the frictional stress that the conductive layer on the molded film experiences when the resin is injected 14 from the opening 13 in Figure 5(C) to form the base material 20, and when the molded film 10 and the base material 20 come into close contact, due to the injection of high-temperature molten resin into the mold. In other words, in this third manufacturing method, the conductive layer is subjected to both tensile stress during molding and frictional stress with the base plastic at high temperatures.

[0080] The molded bodies obtained in this way enable the mounting of circuits, touch sensors, and various electronic components into plastic casings for home appliances, automotive parts, robots, drones, and other devices. Furthermore, this technology is extremely useful for miniaturizing, reducing the size and weight of electronic devices, improving design flexibility, and increasing their functionality. [Examples]

[0081] The present invention will be described in more detail below with reference to examples, but the following examples do not limit the present invention in any way. In the examples, "parts" refers to "parts by mass" and "%" refers to "percentage by mass". Furthermore, the weight-average molecular weight in the examples is the polystyrene-equivalent molecular weight measured using Tosoh Corporation's GPC (gel permeation chromatography) "HLC-8320," with a polystyrene-divinylbenzene-based gel as the stationary phase and tetrahydrofuran as the mobile phase.

[0082] Furthermore, the "functional value" in the examples is calculated based on the molecular weight of each functional group in each raw material (referred to as the functional group equivalent), and is expressed as the amount of functional groups per gram of raw material in terms of equimolar potassium hydroxide equivalent mass (mg) using the following formula. (Functional value) [mgKOH / g] = (56.1 × 1000) / (Functional group equivalent) The above-mentioned functional value is a general term for amounts expressed as, for example, acid value when the functional group is a carboxyl group, hydroxyl value when the functional group is a hydroxyl group, amine value when the functional group is an amino group, and so on. When comparing the functional group ratios of substances that have different functional groups, if the above-mentioned functional value is the same, it can be assumed that they have the same molar amount of functional group.

[0083] When titrating with potassium hydroxide to quantify functional groups such as carboxyl groups and hydroxyl groups, the above functional values ​​can also be directly determined from the appropriate amount of potassium hydroxide used for neutralization using a publicly known and widely used measurement method specified in JIS K 0070, for example, and can be treated in the same way as the calculated values ​​using the above formula. Furthermore, even when titration with potassium hydroxide is not used to quantify the functional value of isocyanate groups, the amount can be conveniently calculated as a potassium hydroxide equivalent using the functional group equivalents derived from the measured values ​​representing the amount of each functional group, as well as the above calculation formula. A specific calculation example is shown below.

[0084] Calculation Example: We will calculate the equivalent value of a trifunctional isocyanate compound "X" which has an isocyanate group and whose isocyanate content is 23%, as measured by the method specified in JIS K 6806 (a method in which the isocyanate group is reacted with n-dibutylamine and the remaining n-dibutylamine is titrated with an aqueous hydrochloric acid solution). The functional group equivalent of the trifunctional isocyanate compound "X" is derived from the above isocyanate content (%) and the molecular weight of the isocyanate group (NCO = 44 g / mol) as follows. (Equivalent of the functional group of "X") = 1 / (0.23 / 44) = 191.3 From the functional group equivalents of this trifunctional isocyanate compound "X" and the above formula for calculating the functional value, the functional value of the trifunctional isocyanate compound "X" can be calculated as follows. (Functional value of trifunctional isocyanate compound "X") [mgKOH / g] =(56.1 × 1000) / 191.3 = 293.3

[0085] Furthermore, the weight ratio of trifunctional monomers and tetrafunctional monomers in the constituent monomers of the resin in the examples was determined after the resin was purified by reprecipitation and filtration and dried. 13 The chemical shifts of the peaks obtained by 13C-NMR quantitative measurement (measurement solvent: chloroform-d, pulse interval 20 seconds, gated decoupling: non-NOE mode (NNE), number of integrations 4000 times) were matched with values ​​obtained for carbon atom nuclei in known structures and assigned to identify all constituent monomer structures and their molar ratios. Based on these identified structures, the mass ratio of each constituent monomer in the resin was calculated to determine its composition.

[0086] <Resin (A1)~(A3)>

[0087] <Synthesis Example 1: Synthesis of Resin (A1-1)> In a reactor equipped with a stirrer, thermometer, rectification tube, nitrogen gas inlet tube, and vacuum device, 25.0 parts isophthalic acid, 25.0 parts terephthalic acid, 14.0 parts ethylene glycol, 10.0 parts neopentyl glycol, 3.0 parts trimellitic acid, and 0.03 parts tetrabutyl titanate as a catalyst were charged. The mixture was gradually heated to 180°C while stirring under a nitrogen stream, and the transesterification reaction was carried out at 180°C for 3 hours while distilling off the excess glycol component. The acid value was measured, and when it fell to 15 or less, the pressure in the reactor was gradually reduced to 1-2 toll. When the desired viscosity was reached, the reaction was stopped, and after removal, the mixture was transferred to a fluorine-coated pallet and cooled to obtain a solid polyester resin (A1-1) with a number average molecular weight of 24,000, a hydroxyl group (functional value 6 mg KOH / g), a ratio of trifunctional monomers to tetrafunctional monomers in the constituent monomers of 3.6% by weight, and an aromatic ring structure in the main chain.

[0088] <Synthesis Examples 2-12: Synthesis of resins (A1-2)-(A1-11) and other resins (A2-1)> Except for changing the raw materials other than the catalyst and their amounts as shown in Table 1, solids of the polyester resins (A1-2) to (A1-11) and (A2-1) shown in Table 1 were obtained in the same manner as in Synthesis Example 1.

[0089] <Synthesis Example 13: Synthesis of Other Resins (A2-2)> In a reactor equipped with a stirrer, thermometer, rectification tube, nitrogen gas inlet tube, and vacuum device, 150.0 parts of coconut oil and 48.0 parts of pentaerythritol were charged. Heating was started using a mantle heater under a nitrogen gas atmosphere, and when the temperature reached 200°C, 1.0 part of 5% lithium hydroxide (alcohol / water mixture) was added as a catalyst. The temperature was gradually increased to 240°C and maintained there. After confirming that the transesterification reaction had progressed and the turbid reaction solution had become clear, stirring was continued for another hour, and the mixture was maintained for a total of 2 hours to complete the transesterification reaction. After cooling to a temperature below 100°C, 3.6 parts of ethylene glycol, 93.0 parts of phthalic anhydride, and 15.0 parts of the monofunctional monomer para-tert-butylphenol were added. Next, 30 ml of xylene was added to a decounter to remove the condensation reaction water produced by the esterification reaction, and the mixture was heated to 225°C and maintained there for approximately 2 hours. The reaction was terminated when the amount of condensation reaction water reached the planned amount (12.9 g), and the mixture was transferred to a fluorine-coated pallet and cooled to obtain a solid alkyd resin (A'2) with a weight-average molecular weight of 9,000, a hydroxyl group (functional value 1 mg KOH / g), a ratio of trifunctional monomers and tetrafunctional monomers in the constituent monomers of 16.6% by weight, and an aromatic ring structure in the main chain. As stated above, alkyd resin (A2-2) contains 5.3% by mass of monofunctional monomer (para-tertish-butylphenol) and 52.9% by mass of oil and fat (coconut oil), totaling 58.2% by mass (20% by mass or more), and is therefore not included in the polyester resin of the present invention.

[0090] <Synthesis Example 14: Synthesis of Resin (A1-12)> In a reaction apparatus equipped with a stirrer, thermometer, reflux condenser, and nitrogen gas inlet, 100.0 parts of polyester polyol obtained from the alternating copolymerization of isophthalic acid and 3-methyl-1,5-pentanediol (Kuraray Polyol P-2030, manufactured by Kuraray Co., Ltd.), 5 parts of trimethylolpropane, 22.0 parts of isophorone diisocyanate, and 36.5 parts of toluene were charged. The mixture was reacted at 90°C for 3 hours under a nitrogen atmosphere, then cooled to stop the reaction. Finally, the mixture was removed and transferred to a fluorine-coated pallet. It was then dried in a hot air drying oven at 120°C for 5 hours, followed by vacuum drying for 24 hours, to obtain a solid urethane resin (A1-12) with a weight-average molecular weight of 23,000, hydroxyl groups (functional value 5 mg KOH / g), a ratio of trifunctional monomers to tetrafunctional monomers in the constituent monomers of 3.9% by weight, and an aromatic ring structure in the main chain.

[0091] <Synthesis Examples 15-21: Synthesis of resins (A1-13)-(A1-18) and other resins (A2-3)> Except for changing the raw materials and their quantities as shown in Table 2, the solid urethane resins (A1-13) to (A1-18) and (A2-3) shown in Table 2 were obtained in the same manner as in Synthesis Example 13. The contents of the raw materials not indicated by compound name are as follows.

[0092] • P-2010: A polyester polyol obtained by alternating copolymerization of adipic acid and 3-methyl-1,5-pentanediol (Kuraray Polyol P-2010, manufactured by Kuraray Co., Ltd.) • PTG-1000: A polyether polyol obtained from the ring-opening polymerization of tetrahydrofuran (manufactured by Hodogaya Chemical Co., Ltd. as "PTG-1000"). • F-1010: A polyester polyol obtained by alternating copolymerization of adipic acid, 3-methyl-1,5-pentanediol, and trimethylolpropane (Kuraray Polyol F-1010, manufactured by Kuraray Co., Ltd.)

[0093] <Synthesis Example 22: Synthesis of Resin (A1-19)> In a reactor equipped with a stirrer, thermometer, reflux condenser, and nitrogen gas inlet, 4.0 parts of isophthalic acid, 2.0 parts of trimellitic acid, 70 parts of polyetherdiamine (Huntsman's "Jeffermin D-2000") obtained by ring-opening polymerization of propylene oxide in which the molecular chain ends are converted to amino groups, and 36.5 parts of toluene were charged. The reaction was carried out under reflux at 110°C for 2 hours under a nitrogen stream, and then the temperature was gradually heated to 180°C, and the reaction was continued for 3 hours while the solvent and condensed water were removed by distillation to stop the reaction. The mixture was then transferred to a fluorine-coated pallet and cooled to obtain a solid polyamide resin (A1-19) with a number average molecular weight of 18,000, an amino group (functional value of 7 mg KOH / g), a ratio of trifunctional monomers to tetrafunctional monomers in the constituent monomers of 2.1% by weight, and an aromatic ring structure in the main chain.

[0094] <Synthesis Examples 23-27: Synthesis of resins (A1-20)-(A1-23) and other resins (A2-4)> Except for changing the raw materials and their quantities as shown in Table 3, the solid polyamide resins (A1-20) to (A1-23) and (A2-4) shown in Table 3 were obtained in the same manner as in Synthesis Example 21. Note that polyamide resins (A1-34) and (A1-35) do not contain amino groups, but have carboxyl groups as functional groups. Furthermore, the contents of the raw materials not indicated by compound names are as follows.

[0095] • Prepol 1009: Hydrogenation and the resulting dimer acid monomer (Prepol 1009, manufactured by Croda).

[0096] <Synthesis Example 28: Synthesis of Resin (A1-24)> In a reaction apparatus equipped with a stirrer, thermometer, reflux condenser, and nitrogen gas inlet, 30.0 parts neopentyl glycol, 30.0 parts 1,6-hexanediol, 2.0 parts trimethylolpropane, 45.0 parts ethylene carbonate, and 40.0 parts toluene were charged. The reaction was carried out under reflux at 110°C for 2 hours under a nitrogen stream. The temperature was then gradually increased to 180°C, and the reaction was continued for 3 hours while distilling off the solvent and the ethylene glycol produced by condensation to stop the reaction. The mixture was then transferred to a fluorine-coated pallet and cooled to obtain a solid polycarbonate resin (A1-24) with a number average molecular weight of 18,000, hydroxyl groups (functional value of 6 mg KOH / g), a ratio of trifunctional monomers to tetrafunctional monomers in the constituent monomers of 2.6% by weight, and no aromatic ring structure in the main chain.

[0097] The following conductive fine particles, solvents, and crosslinking agents were used. <Conductive fine particles (B1)~(B5)> • Conductive fine particles (B1): Manufactured by Fukuda Metal Foil & Powder Co., Ltd., flake-shaped silver powder, average particle size 5.2 μm ·Conductive fine particles (B2): Manufactured by Fukuda Metal Foil and Powder Co., Ltd., chain agglomerated silver powder, average particle size 1.7μm • Conductive microparticles (B3): Manufactured by Mitsui Mining & Smelting Co., Ltd., silver-coated copper powder, silver coating amount 10%, average particle size 2.0 μm • Conductive microparticles (B4): Manufactured by Ishihara Sangyo Co., Ltd., needle-shaped conductive Sb-doped tin oxide powder, average particle size 2.9 μm • Conductive microparticles (B5): Manufactured by Ito Graphite Co., Ltd., expanded graphite, average particle size 15 μm

[0098] <Solvents (C1)~(C4)> The following was used as solvent (C). • Solvent (C1): Benzyl alcohol • Solvent (C2): Dipropylene glycol monomethyl ether • Solvent (C3): Diethylene glycol monobutyl ether acetate • Solvent (C4): 2-methoxypropanol

[0099] <Crosslinking agents (D1)~(D3)> • Crosslinking agent (D1): Baxeneden Chemicals' blocked isocyanate solution, Trixene BI7982, contains three blocked isocyanate groups per molecule (functional value 195 mg KOH / g), non-volatile content 70% (solvent (C4): 2-methoxypropanol). • Crosslinking agent (D2): Blocked isocyanate solution manufactured by Baxeneden Chemicals, Trixene BI7960, containing 3 blocked isocyanate groups per molecule (functional value 195 mg KOH / g), non-volatile content 70% (solvent (C4): 2-methoxypropanol) • Crosslinking agent (D3): TETRAD-X epoxy resin manufactured by Mitsubishi Gas Chemical Company, contains 4 epoxy groups per molecule (functional value 623 mg KOH / g), 100% non-volatile content.

[0100] <Manufacturing Example 1: Creation of decorative ink (E1)> 200 parts of a resin solution consisting of 80 parts of resin (A1-12) and 120 parts of solvent (C3) were prepared. 20 parts of phthalocyanine blue pigment (LIONOL BLUE FG7351, manufactured by Toyo Color Co., Ltd.) and 10 parts by mass of titanium dioxide pigment (TIPAQUE CR-93, manufactured by Ishihara Sangyo Co., Ltd.) were stirred and mixed. After kneading in a three-roll mill (manufactured by Kodaira Seisakusho Co., Ltd.), 5 parts of isocyanate crosslinking agent (Desmodule N3300, manufactured by Sumika Covestro Urethane Co., Ltd., 100% non-volatile content) and 90 parts of solvent (C3) were added and stirred uniformly to obtain decorative ink (E1).

[0101] <Example 1: Preparation of conductive composition (F1) for molded film> A conductive composition (F1) for molded films was obtained by dissolving 20.0 parts of resin (A1-1) in 30.0 parts of solvent (C1), stirring and mixing with 80.0 parts of conductive fine particles (B1), kneading in a three-roll mill (manufactured by Kodaira Seisakusho), and then adding 1.0 part of crosslinking agent (D1) and stirring uniformly in a planetary mixer.

[0102] <Examples 2-57: Preparation of conductive compositions (F2)-(F57) for molded films> In Example 1, conductive compositions for molded films (F2) to (F57) were obtained in the same manner as in Example 1, except that the types and amounts of resin, solvent, conductive fine particles, and crosslinking agent (if a crosslinking agent is used, it was added immediately before uniform stirring and mixing with a planetary mixer, as in Example 1) were changed as shown in Tables 5 to 8. Note that the values ​​for each material in Tables 5-8 are all in parts by mass.

[0103] <Comparative Examples 1-4: Preparation of conductive compositions (F58)-(F61) for molded films> Conductive compositions for molded films (F58) to (F61) were obtained in the same manner as in Example 1, except that the type and amount of resin, solvent, conductive fine particles, and crosslinking agent were changed as shown in Table 8.

[0104] <Examples 58-114 and Comparative Examples 5-8> On a polycarbonate (PC) base film (Teijin, Panlite 2151, 300 μm thick, 300 mm x 210 mm), conductive compositions for molded films (F1) to (F55) were printed at a printing speed of 50 mm / sec using a screen printing machine (Minoscreen, Minomat SR5575 semi-automatic screen printing machine). Subsequently, the film was heated in a hot air drying oven at 120°C for 30 minutes to obtain a molded film having a conductive layer with a rectangular solid pattern of 15 mm width, 30 mm length, and 10 μm thickness, a linear pattern of 3 mm line width, 60 mm length, and 10 μm thickness, and a stripe pattern of 150 μm line width, 150 μm line spacing, and 60 mm length.

[0105] <Example 115> A decorative ink (G1) was applied to a polycarbonate base film (Teijin Corporation, Panlite 2151, 300 μm thick, 300 mm x 210 mm) using a blade coater to a dry film thickness of 2 μm, and the decorative layer was formed by heating at 120°C for 30 minutes. Next, in the same manner as in Example 58, except that the decorative layered film was used instead of the polycarbonate base film and a conductive layer was formed on the decorative layer, a molded film was obtained in which a polycarbonate film, a decorative ink layer, and a conductive material were laminated in that order.

[0106] <Example 116> In Example 58, a two-layer co-extruded film of polycarbonate resin / acrylic resin (manufactured by Sumitomo Chemical Co., Ltd., Technoloy C001, 125 μm thick, 300 mm × 210 mm) was used instead of a polycarbonate base film, and a conductive composition for molded films was printed on the polycarbonate resin side. A molded film was obtained in the same manner as in Example 58, except that the polycarbonate base film was replaced with a two-layer co-extruded film of two types of polycarbonate resin / acrylic resin (manufactured by Sumitomo Chemical Co., Ltd., Technoloy C001, 125 μm thick, 300 mm × 210 mm).

[0107] <Example 117> A molded film was obtained in the same manner as in Example 58, except that an acrylic resin film (Sumita Chemical Co., Ltd., Technoloy S001G, 250 μm thick, 300 mm x 210 mm) was used instead of a polycarbonate base film, and the drying conditions in the hot air drying oven were set to 80°C for 30 minutes.

[0108] <Example 118> A molded film was obtained in the same manner as in Example 58, except that an easily moldable PET resin film (Morino Kako Co., Ltd., Emron PETG resin sheet, 250 μm thick, 300 mm x 210 mm) was used instead of a polycarbonate base film, and the drying conditions in the hot air drying oven were set to 70°C for 30 minutes.

[0109] <Example 119> A molded film was obtained in the same manner as in Example 58, except that a polypropylene film (Idemitsu Unitech Co., Ltd., Pure Thermo AG-306, 200 μm thick, 300 mm x 210 mm) was used instead of a polycarbonate film, and the drying conditions in the hot air drying oven were set to 80°C for 30 minutes.

[0110] [(1) Volume resistivity measurement] The volume resistivity (Ω·cm) of the 15mm × 30mm rectangular solid conductive layer formed on the molded films of Examples 58 to 119 and Comparative Examples 5 to 8 was measured using a resistivity meter (Mitsubishi Chemical Analytec, Loresta GP MCP-T610 resistivity meter, compliant with JIS-K7194, 4-terminal 4-probe statutory current application method) (4-terminal probes spaced 0.5cm apart). The results are shown in Tables 5 to 8.

[0111] [(2) Evaluation of peelability and adhesion] For the 15mm x 30mm rectangular solid conductive layer formed on the molded films of Examples 58-119 and Comparative Examples 5-8, a 10x10 grid pattern of cuts was made through the conductive layer using a utility knife with a 1mm spaced cross-cut guide manufactured by Gardner Corporation. Cellophane tape manufactured by Nichiban Corporation was then applied, and after removing any trapped air and ensuring good adhesion, the tape was peeled off vertically. The degree of delamination of the coating was evaluated according to the ASTM D3359 standard as follows. The results are shown in Tables 5-8. (Evaluation criteria for peel-and-adhesion properties) A: Rating 5B-4B, excellent adhesion. B: Although the evaluation is 5B to 4B, the coating film undergoes cohesive failure, and a portion of the coating film on the surface side detaches. C: Rating 3B or lower, poor adhesion.

[0112] [(3) Wiring resistance evaluation] The molded films of Examples 58-119 and Comparative Examples 5-8 were cut to a length of 70 mm in the longitudinal direction and 10 mm in the width direction, with the 3 mm x 60 mm linear pattern conductive layer in the center, to serve as measurement coupons. On the side of the measurement coupon opposite the conductive layer, two lines perpendicular to the conductive layer were drawn at 4 cm intervals using an oil-based marker, starting from the longitudinal end. The resistance values ​​were measured using a tester at positions 4 cm apart according to these marks, and these were defined as the wiring resistance (Ω). The results are shown in Tables 5-8.

[0113] [(4) Heat stretching evaluation 1] The measurement coupons from Examples 58-116 and Comparative Examples 5-8 were stretched in a 160°C oven at a longitudinal pulling speed of 100 mm / min until they reached 100% elongation. After removal from the oven and cooling, the presence or absence of breakage was evaluated using an optical microscope. In addition, the wiring resistance (Ω) was measured at positions corresponding to 4 cm intervals relative to the original markers using the same method as for measuring the wiring resistance described above. The ratio of the wiring resistance after stretching to the wiring resistance before stretching was defined as the resistance change rate (times) during thermal stretching, and each was evaluated according to the following criteria. The results are shown in Tables 5-8. (Presence or absence of broken wires) A: No breaks in the wire were observed. B: One to two minor cracks were found. C: Severe wire breakage or peeling of the conductive coating was observed. (Resistance variation rate during thermal stretching) A: 5 times or more but less than 10 times B: 10 times or more but less than 100 times C: 100 times or more

[0114] The growth rate is calculated as follows: (Elongation rate) [%] = {(Length after stretching - Length before stretching) / (Length before stretching)} × 100

[0115] [(5) Heat stretching evaluation 2] In the aforementioned heat stretch evaluation 1, the evaluation was carried out in the same manner as in the aforementioned heat stretch evaluation 1, except that the elongation rate was changed to 150%, and according to the following criteria. The results are shown in Tables 5 to 8. (Presence or absence of broken wires) A: No breaks in the wire were observed. B: One to two minor cracks were found. C: Severe wire breakage or peeling of the conductive coating was observed. (Resistance variation rate during thermal stretching) A: 10 times or more but less than 100 times B: 100 times or more but less than 1000 times C:1000 times or more

[0116] [(6) Heat stretching evaluation 3] The measurement coupons from Examples 117-119 were stretched in a 120°C oven at a longitudinal pulling speed of 100 mm / min until they reached 100% elongation. After being removed from the oven and cooled, the presence or absence of breakage was evaluated using an optical microscope. In addition, the wiring resistance (Ω) was measured at positions corresponding to 4 mm intervals relative to the original markers using the same method as for measuring the wiring resistance described above. The ratio of the wiring resistance after stretching to the wiring resistance before stretching was defined as the resistance change rate (times) during thermal stretching, and each was evaluated according to the following criteria. The results are shown in Tables 7-8. (Presence or absence of broken wires) A: No breaks in the wire were observed. B: One to two minor cracks were found. C: Severe wire breakage or peeling of the conductive coating was observed. (Resistance variation rate during thermal stretching) A: 5 times or more but less than 10 times B: 10 times or more but less than 100 times C: 100 times or more

[0117] [(7) Heat stretching evaluation 4] In the aforementioned heat stretch evaluation 3, the evaluation was performed in the same manner as in the aforementioned heat stretch evaluation 3, except that the elongation rate was changed to 150%, and according to the following criteria. The results are shown in Tables 7 and 8. (Presence or absence of broken wires) A: No breaks in the wire were observed. B: One to two minor cracks were found. C: Severe wire breakage or peeling of the conductive coating was observed. (Resistance variation rate during thermal stretching) A: 10 times or more but less than 100 times B: 100 times or more but less than 1000 times C:1000 times or more

[0118] [(8) Process tolerance evaluation during the manufacture of molded products by overlay molding 1] A rectangular parallelepiped ABS resin molded object, 10 mm high and 30 mm x 30 mm in size, was aligned with the conductive side of the molded film in Examples 58-116 and Comparative Examples 5-8, so as to overlap with the position of the 3 mm x 60 mm linear pattern of the molded film. Overlay molding was performed using a TOM molding machine (manufactured by Fuse Vacuum Co., Ltd.) at a set temperature of 160°C to obtain a molded body in which the rectangular parallelepiped molded film and the ABS resin molded object were integrated. The wear and resistance fluctuation rate of the linear pattern wiring of this molded body were checked. The resistance fluctuation rate was measured by measuring the wiring resistance (Ω) at positions corresponding to 6 cm intervals relative to the original markers. The resistance fluctuation rate during heat stretching was defined as the wiring resistance after stretching / wiring resistance before stretching, and each was evaluated according to the following criteria. The results are shown in Tables 5-8. (Presence or absence of breakage and resistance fluctuation rate) A: No wear was observed in the wiring, and the resistance fluctuation rate was between 10 and 50 times. B: End chipping due to wear on 1-2 wires is observed, or the resistance fluctuation rate is between 50 and 500 times. C: One or more instances of wire breakage due to wear were found.

[0119] [(9) Process tolerance evaluation during the manufacturing of molded products by overlay molding 2] Except for using the 3mm x 60mm linear patterns of the molded films from Examples 117 to 119 above and performing overlay molding at 120°C, molded bodies were obtained in the same manner as in Process Tolerance Evaluation 1 during molded body production by overlay molding, and the wear and resistance fluctuation rate of the linear pattern wiring during overlay molding were evaluated. The results are shown in Tables 7 and 8.

[0120] [(10) Process tolerance evaluation during the manufacturing of molded products by film insert molding 1] A block-shaped metal mold having a rectangular parallelepiped projection measuring 30mm x 30mm with a 20mm step in the center was placed facing the opposite side of the conductive material, so as to overlap with the position of the 3mm x 60mm linear pattern of the molded films of Examples 58 to 116 and Comparative Examples 5 to 8. Overlay molding was performed using a TOM molding machine (manufactured by Fuse Vacuum Co., Ltd.) at a set temperature of 160°C to obtain a molded film having a patterned conductive material on the inside of a rectangular parallelepiped shape. Next, the molded rectangular parallelepiped film was placed in an injection molding machine (IS170(i5), manufactured by Toshiba Machine Co., Ltd.) equipped with a valve gate type in-mold molding test mold, and PC / ABS resin (LUPOYPC / ABSHI5002, manufactured by LG Chem Co., Ltd.) was injection molded to obtain a molded body integrated with the patterned conductive molding film (injection conditions: screw diameter 40 mm, cylinder temperature 260°C, mold temperature (fixed side, movable side) 60°C, injection pressure 160 MPa (80%), holding pressure 100 MPa, injection speed 60 mm / sec (28%), injection time 4 seconds, cooling time 20 seconds). Washout (deformation or breakage of the wiring pattern due to the temperature of the molten thermoplastic resin and injection pressure) and resistance fluctuation rate of the linear pattern of this molded body were confirmed. The resistance fluctuation rate was determined by measuring the wiring resistance (Ω) at positions corresponding to 6 cm intervals based on the original marker reference. The ratio of the wiring resistance after stretching to the wiring resistance before stretching was defined as the resistance fluctuation rate (times) during thermal stretching, and each was evaluated according to the following criteria. The results are shown in Tables 5-8. (Presence or absence of breakage and resistance fluctuation rate) A: No wiring washout is observed, and the resistance fluctuation rate is between 10 and 50 times. B: Wiring distortion due to mild washout is observed, or the resistance fluctuation rate is between 50 and 500 times. C: One or more instances of wire breakage due to wiring washout are confirmed.

[0121] [(11) Process tolerance evaluation during the manufacturing of molded products by film insert molding 2] Except for using the 3 mm x 60 mm linear patterns of the molded films from Examples 117 to 119 above and performing overlay molding at 120°C, molded bodies were obtained in the same manner as in Process Tolerance Evaluation 1 during molded body production by overlay molding, and the degree of washout and resistance fluctuation rate due to molten resin injection of the linear patterns during film insert molding were evaluated. The results are shown in Tables 7 and 8.

[0122] [(12) Ball impact test of molded body] The impact resistance of the molded bodies obtained in Examples 58-116 and Comparative Examples 5-8 [(10) Process resistance evaluation 1 during molded body manufacturing by film insert molding] and in Examples 117-119 [(11) Process resistance evaluation 2 during molded body manufacturing by film insert molding] was evaluated by conducting a ball drop impact test. Using a Shimadzu Corporation "JIS Ball Drop Impact Tester IM-4100," the resulting molded body was mounted in a predetermined position, and a 500g steel ball was dropped from a height of 80cm onto the center of the molded body. The presence or absence of cracks in the wiring and the presence or absence of continuity were observed visually from the film side. The presence or absence of continuity was confirmed by touching both measuring parts of the tester to the conductive layer of the linear pattern and measuring the resistance value of the conductive layer. These results were then comprehensively evaluated according to the following criteria. The results are shown in Tables 5 to 8. (Presence or absence of cracks) A: Continuity was confirmed, and no cracks were found in the wiring. B: Continuity was confirmed, but several minor cracks were found in the wiring. C: No continuity was detected, and a clear break in the wiring was observed.

[0123] [Table 1]

[0124] [Table 2]

[0125] [Table 3]

[0126] [Table 4]

[0127] [Table 5]

[0128] [Table 6]

[0129] [Table 7]

[0130] [Table 8]

[0131] [Summary of results] It was revealed that conductive layers formed using the conductive compositions of Comparative Examples 5 to 8, which do not contain resin (A1) as a resin component, were prone to fracture or increased resistance when stretched at high speed under high temperature conditions during the three-dimensional molding process of the molded film, especially when the degree of stretching was large. Furthermore, it was found that even in the final molded article, the wiring was susceptible to breakage when subjected to strong external impacts as a three-dimensional wiring structure.

[0132] On the other hand, the results from Examples 58 to 119 showed that the conductive composition of this embodiment did not experience wire breakage even when stretched at high speed under high temperature conditions during the three-dimensional molding process of the molded film, especially when the elongation was large, and the increase in resistance was also well suppressed. This is presumed to be because the resin component of the conductive composition of this embodiment contains a resin (A1) with a specific molecular structure that includes constituent units derived from trifunctional monomers or tetrafunctional monomers. The dense concentration of functional groups around the branched structure caused by the constituent units derived from trifunctional monomers or tetrafunctional monomers exhibits a reversible yet stronger adsorption behavior at multiple points on the surface of conductive fine particles (B), making it difficult to initiate wire breakage. At the same time, especially when crosslinking agent (D) is used in combination, the polymer chains of the resin (A1) component intertwine well, forming a flexible resin linkage network that spreads over a wide area. This is presumed to have resulted in the excellent high-temperature cohesive force and conductivity retention characteristics of the conductive layer, which can withstand stretching at high temperatures and high speeds during molding.

[0133] Furthermore, due to the above characteristics, a molded film equipped with a conductive layer of the conductive composition of the present invention yielded a molded body with excellent integrated wiring, even with complex three-dimensional shapes where the substrate surface is not flat, particularly with steep steps, and where high-speed, high-elongation stretching deformation occurs in the wiring during molding. Moreover, the impact resistance of the wiring as a molded body obtained after film insert molding was also excellent. This is thought to be because the reversible yet multi-point, stronger adsorption behavior of the resin (A1) component to the surface of the conductive fine particles (B) and the formation of a flexible resin linkage network that spreads over a wide area synergistically mitigate the impact instantaneously without concentrating it on a specific point, making it less likely for voids that could cause wiring breakage to form.

[0134] Thus, the molded film and integrated wiring using the conductive composition of this embodiment enable the direct creation of lightweight and space-saving circuits, as well as the creation of touch sensors, antennas, heating elements (heaters), electromagnetic shields, inductors (coils), resistors, and mounting of various electronic components, without compromising design freedom, into plastic housings and three-dimensional shaped parts of home appliances, automotive parts, robots, drones, etc. Furthermore, it is extremely useful for miniaturizing, reducing the weight and thickness of electronic devices, improving design freedom, and increasing their functionality. [Explanation of Symbols]

[0135] 1 Base film 2. Conductive layer 3. Decorative layer 4 Electronic Components 5 pins 10 Molded film 11 molds 12 Injection mold 13 Opening 14 Injection 15 Up 16 Pressurization 17 Resin 20 Base material 21 Upper chamber box 22 Lower chamber box 30 molded bodies

Claims

1. A conductive composition for manufacturing a molded film for forming a conductive layer on a substrate surface having an uneven surface or a three-dimensional curved surface, It contains a resin (A), conductive fine particles (B), and a solvent (C), The resin (A) is at least one selected from the group consisting of polyester resin, polyurethane resin, polyamide resin, and polycarbonate resin, and includes resin (A1) which contains constituent units derived from trifunctional monomers and / or tetrafunctional monomers. Conductive composition for molded films.

2. The conductive composition for molded films according to claim 1, wherein the total content of constituent units derived from trifunctional monomers and tetrafunctional monomers is 0.1% by mass to 15% by mass in the resin (A).

3. The conductive composition for molded films according to claim 1, wherein the resin (A1) is a resin having hydroxyl groups and / or amino groups.

4. The conductive film composition according to claim 1, wherein the conductive fine particles (B) include at least one conductive fine particle selected from the group consisting of silver powder, copper powder, silver-coated powder, copper alloy powder, conductive oxide powder, and carbon fine particles.

5. The conductive composition for molded films according to claim 1, wherein the ratio of resin (A) in the solid content of the conductive composition is 8 to 40% by mass.

6. The conductive composition for molded films according to claim 1, further comprising a crosslinking agent (D).

7. The conductive composition for molded films according to claim 6, wherein the crosslinking agent (D) is a trifunctional blocked isocyanate crosslinking agent.

8. A molded film comprising a conductive layer on a base film, A molded film in which the conductive layer is a cured product of the conductive composition for molded films according to any one of claims 1 to 7.

9. A molded film comprising a decorative layer and a conductive layer on a base film, A molded film in which the conductive layer is a cured product of the conductive composition for molded films according to any one of claims 1 to 7.

10. The molded film according to claim 8, wherein the base film is a film selected from polycarbonate, polymethyl methacrylate, polypropylene, and polyethylene terephthalate, or a laminated film thereof.

11. A molded body in which a conductive layer is laminated on a substrate, A molded article wherein the conductive layer is a cured product of the conductive composition for molded films according to any one of claims 1 to 7.

12. A step of manufacturing a molded film by printing a conductive composition for molded films according to any one of claims 1 to 7 onto a base film and drying it, A step of placing the molded film on the substrate, A method for manufacturing a molded article, comprising the step of integrating the molded film and the substrate by an overlay molding method.

13. A step of manufacturing a molded film by printing a conductive composition for molded films according to any one of claims 1 to 7 onto a base film and drying it, A step of forming the aforementioned molded film into a predetermined shape, A step of placing the molded film after molding into a mold for injection molding, A method for manufacturing a molded article, comprising the steps of: molding a substrate by injection molding and integrating the molded film with the substrate.

14. A step of manufacturing a molded film by printing a conductive composition for molded films according to any one of claims 1 to 7 onto a base film and drying it, The process of placing the molded film inside a mold for injection molding, A method for manufacturing a molded article, comprising the steps of: molding a substrate by injection molding and transferring a conductive layer in the molded film to the substrate.

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