Three-dimensional molding wiring sheet

Abstract

A wiring sheet for three-dimensional molding formed by sandwiching a pseudo-sheet structure constituted by a plurality of electrically conductive linear bodies arranged at intervals between a first embed layer and a second embed layer. The electrically conductive linear bodies have a wave shape in planar view. The storage shear elastic modulus of the first embed layer and the second embed layer at 23°C are both 1×104 to 3×106Pa. When the thickness of the first embed layer is T1, the thickness of the second embed layer is T2, and the thickness of the pseudo-sheet structure is T3, a specific relational expression is satisfied.

Description

[Technical Field]

[0001] The present invention relates to a wiring sheet for three-dimensional molding. [Background technology]

[0002] BACKGROUND ART In recent years, it has been proposed to use a conductive structure obtained by fixing a conductive member such as a metal wire to a support or the like as a heating element of a heating device.

[0003] For example, Patent Document 1 describes a sheet (hereinafter sometimes referred to as a "wiring sheet") having a pseudo-sheet structure in which a plurality of linear bodies extending in one direction are arranged at intervals.

[0004] Furthermore, three-dimensional molding methods such as TOM (Three Dimension Overlay Method) molding, film insert molding, and vacuum forming are known as techniques for imparting functionality such as designability and scratch resistance to the surfaces of molded products used in home appliance housings, vehicle interior parts, building materials, and the like (see, for example, Patent Document 2). [Prior art documents] [Patent documents]

[0005] [Patent Document 1] International Publication No. 2017 / 086395 (US2018 / 0326697A1) [Patent Document 2] Japanese Patent Application Laid-Open No. 2015-182438 Summary of the Invention [Problem to be solved by the invention]

[0006] Conventionally, when a three-dimensional molding process is performed on a wiring sheet such as that described in Patent Document 1, the linear bodies, etc. may move during the process, causing cavities around the linear bodies, etc., resulting in problems with poor appearance.

[0007] The present invention has been made in view of the above circumstances, and has an object to provide a wiring sheet that is less likely to have problems with poor appearance after three-dimensional molding processing. [Means for solving the problem]

[0008] In order to solve the above problems, the present inventors have conducted extensive research into a wiring sheet having a pseudo-sheet structure made up of a plurality of conductive linear members. As a result, we discovered that a wiring sheet for three-dimensional molding in which a pseudo-sheet structure is sandwiched between a first embedded layer and a second embedded layer, in which the storage shear moduli of the first embedded layer and the second embedded layer are within a specific range and which meets specific requirements regarding the thickness of the first embedded layer, the thickness of the second embedded layer, and the thickness of the pseudo-sheet structure, is less likely to have problems with poor appearance after three-dimensional molding processing, and we have completed the present invention.

[0009] Thus, according to the present invention, there are provided wiring sheets for three-dimensional molding as described below in [1] to [6].

[0010] [1] A wiring sheet for three-dimensional molding, in which a pseudo-sheet structure made up of a plurality of conductive linear bodies arranged at intervals is sandwiched between a first buried layer and a second buried layer, the conductive linear bodies having a wave shape in a plan view, and the storage shear modulus of elasticity at 23°C of both the first buried layer and the second buried layer being 1.0 × 10 4 ~3.0×10 6 Pa, where T1 is the thickness of the first buried layer, T2 is the thickness of the second buried layer, and T3 is the thickness of the pseudo sheet structure, and the wiring sheet for three-dimensional molding satisfies the following formula:

[0011]

number

[0012] [2] The wiring sheet for three-dimensional molding according to [1], wherein the cross section of the conductive linear body has a circular shape with a diameter of 7 to 75 μm. [3] The wiring sheet for three-dimensional molding according to [1] or [2], wherein the first buried layer and the second buried layer have the same composition. [4] The wiring sheet for three-dimensional molding according to any one of [1] to [3], wherein the first embedding layer and the second embedding layer are curable. [5] A wiring sheet for three-dimensional molding according to any one of [1] to [4], which has a first resin layer adjacent to the first buried layer and / or a second resin layer adjacent to the second buried layer. [6] The wiring sheet for three-dimensional molding described in [5], wherein the surface of the first resin layer facing the first buried layer and / or the surface of the second resin layer facing the second buried layer are peelable. [Effects of the Invention]

[0013] According to the present invention, there is provided a wiring sheet for three-dimensional molding that is less likely to have problems with poor appearance after three-dimensional molding processing. [Brief explanation of the drawings]

[0014] [Figure 1] 1 is a schematic perspective view of a wiring sheet for three-dimensional molding according to one embodiment of the present invention. [Figure 2] FIG. 2 is a schematic plan view of the wiring sheet for three-dimensional molding shown in FIG. [Figure 3] 1 is a schematic perspective view of a wiring sheet for three-dimensional molding according to one embodiment of the present invention. [Figure 4] 1 is a schematic perspective view of a wiring sheet for three-dimensional molding according to one embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0015] The wiring sheet for three-dimensional molding of the present invention is a wiring sheet for three-dimensional molding in which a pseudo-sheet structure made up of a plurality of conductive linear members arranged at intervals is sandwiched between a first buried layer and a second buried layer, the conductive linear members having a wave shape in a plan view, and the storage shear modulus of elasticity at 23°C of both the first buried layer and the second buried layer being 1.0 × 10 4 ~3.0×10 6 Pa, and the following formula is satisfied when the thickness of the first buried layer is T1, the thickness of the second buried layer is T2, and the thickness of the pseudo sheet structure is T3.

[0016]

number

[0017] The structure of the wiring sheet for three-dimensional molding of the present invention will be described below with reference to the drawings, in which some parts are shown enlarged or reduced in size for ease of explanation.

[0018] 1 and 2, a wiring sheet for three-dimensional molding 100 is formed by sandwiching a pseudo-sheet structure 2a made up of a plurality (four) of conductive linear bodies 1a between a first buried layer 3a and a second buried layer 4a. The conductive linear bodies 1a have a wave shape in a plan view.

[0019] The wiring sheet for three-dimensional molding of the present invention may have a first resin layer adjacent to the first buried layer, and a second resin layer adjacent to the second buried layer. 3 shows a wiring sheet 200 for three-dimensional molding, in which a pseudo sheet structure 2b made up of a plurality (four) of conductive linear members 1b is sandwiched between a first buried layer 3b and a second buried layer 4b. The wiring sheet 200 for three-dimensional molding further has a first resin layer 5b adjacent to the first buried layer 3b.

[0020] 4 shows a wiring sheet 300 for three-dimensional molding, in which a pseudo sheet structure 2c made up of a plurality (four) of conductive linear members 1c is sandwiched between a first buried layer 3c and a second buried layer 4c. The wiring sheet 300 for three-dimensional molding further includes a first resin layer 5c adjacent to the first buried layer 3c and a second resin layer 6c adjacent to the second buried layer 4c. Hereinafter, each of the components constituting the wiring sheet for three-dimensional molding of the present invention will be described.

[0021] [Conductive linear body] The conductive linear members of the wiring sheet for three-dimensional molding of the present invention are linear members having electrical conductivity. When the wiring sheet for three-dimensional molding of the present invention is used as a manufacturing material for a heating element of a heating device, the conductive linear members are the heat-generating members.

[0022] The conductive linear elements in the wiring sheet for three-dimensional forming of the present invention have a wave shape in plan view, such as a sine wave, a rectangular wave, a triangular wave, a sawtooth wave, etc. Because the conductive linear members in the wiring sheet for three-dimensional molding of the present invention have a wavy shape in a plan view, they straighten when stretched during three-dimensional molding, and can stretch in accordance with the stretching of the wiring sheet for three-dimensional molding. Therefore, the wiring sheet for three-dimensional molding of the present invention is less likely to experience problems such as wire breakage during the three-dimensional molding process.

[0023] The wavelength of the corrugated conductive linear body is usually 0.3 to 100 mm, preferably 0.5 to 80 mm. The amplitude of the corrugated conductive linear body is usually 0.3 to 200 mm, preferably 0.5 to 160 mm.

[0024] The cross-sectional shape of the conductive linear body is not particularly limited. Examples of the cross-sectional shape of the conductive linear body include a circular shape, an elliptical shape, a flat shape, a polygonal shape, etc. Among these, a circular shape is preferred. When the cross section of the conductive linear body is circular, the diameter of the conductive linear body is preferably 7 to 75 μm, more preferably 8 to 60 μm, and even more preferably 12 to 40 μm. When the cross section of the conductive linear body is a circle having the above-mentioned diameter, the conductive linear body has an appropriate resistance and improves heat generation efficiency.

[0025] The cross-sectional shape and diameter of the conductive linear body can be determined by observing the conductive linear body using a digital microscope.

[0026] The volume resistivity of the conductive linear body is preferably 1.0×10 -9 ~1.0×10 -3 Ω·m, more preferably 1.0×10 -8 ~1.0×10 -4 Ω·m. When the volume resistivity of the conductive linear bodies is within the above range, it becomes easier to obtain a wiring sheet for three-dimensional molding that is suitable as a heating element. The volume resistivity of the conductive linear body is a known value at 25°C, and is the value listed in the Chemical Handbook (Basic Edition), 4th Revised Edition (editor: Chemical Society of Japan). The volume resistivity value of an alloy not listed in the Chemical Handbook is the value disclosed by the alloy manufacturer.

[0027] Examples of the conductive linear body include a linear body containing a metal wire, a linear body containing a carbon nanotube, and a linear body made of a thread coated with a conductive material.

[0028] A linear body including a metal wire (hereinafter sometimes referred to as a "metal wire linear body") may be a linear body made of a single metal wire, or may be a linear body obtained by twisting together multiple metal wires. It may also be a linear body having a core wire made of a first metal and a metal coating made of a second metal different from the first metal that is provided on the outside of the core wire.

[0029] Examples of metals that may be used to form metal wires include copper, aluminum, tungsten, iron, molybdenum, nickel, titanium, silver, and gold; and alloys containing two or more metals (e.g., steels such as stainless steel and carbon steel, brass, phosphor bronze, zirconium-copper alloys, beryllium copper, iron-nickel, nichrome, nickel-titanium, Kanthal, Hastelloy, and rhenium-tungsten).

[0030] The surface of the metal wire may be coated with a carbon material. Examples of carbon materials that can be used to coat the metal wire include amorphous carbon (such as carbon black, activated carbon, hard carbon, soft carbon, mesoporous carbon, and carbon fiber), graphite, fullerene, graphene, and carbon nanotubes.

[0031] A linear body containing carbon nanotubes (hereinafter, sometimes referred to as a "carbon nanotube linear body") is a linear body containing carbon nanotubes as a conductive material. A linear carbon nanotube can be obtained, for example, by drawing carbon nanotubes into a sheet from the end of a carbon nanotube forest (a growth body in which multiple carbon nanotubes are grown on a substrate so that they are oriented perpendicular to the substrate), bundling the drawn carbon nanotube sheets, and then twisting the bundles of carbon nanotubes.

[0032] According to this manufacturing method, a linear carbon nanotube body with high purity can be obtained. In this manufacturing method, when no twist is applied during twisting, a ribbon-shaped carbon nanotube linear body is obtained, whereas when a twist is applied, a thread-shaped carbon nanotube linear body is obtained. The ribbon-shaped carbon nanotube linear body is a linear body in which the carbon nanotubes do not have a twisted structure.

[0033] Alternatively, linear carbon nanotubes can be obtained by spinning a dispersion of carbon nanotubes. The linear carbon nanotubes can be produced by spinning, for example, by the method disclosed in U.S. Patent Application Publication No. 2013 / 0251619 (JP 2012-126635 A).

[0034] The linear carbon nanotube body may be formed by weaving two or more linear carbon nanotubes together, or may be formed by combining carbon nanotubes with other conductive materials (hereinafter, sometimes referred to as a "composite linear body").

[0035] Examples of composite linear bodies include: (1) composite linear bodies obtained by supporting a metal element or a metal alloy on the surface of a carbon nanotube forest, sheet, or bundle, or twisted linear body by vapor deposition, ion plating, sputtering, wet plating, etc., during the process of obtaining a carbon nanotube linear body (specifically, a process of drawing carbon nanotubes into a sheet form from the end of a carbon nanotube forest, bundling the drawn carbon nanotube sheet, and then twisting the carbon nanotube bundles); (2) composite linear bodies obtained by twisting bundles of carbon nanotubes together with linear bodies of a metal element or a metal alloy, or composite linear bodies; and (3) composite linear bodies obtained by weaving linear bodies of a metal element or a metal alloy, or composite linear bodies, with carbon nanotube linear bodies or composite linear bodies. In the composite linear body of (2), when twisting the bundles of carbon nanotubes, a metal may be supported on the carbon nanotubes as in the composite linear body of (1). Also, the composite linear body of (3) is a composite linear body in which two linear bodies are braided, but it may be a composite linear body in which three or more carbon nanotube linear bodies, or linear bodies of a metal or a metal alloy, or composite linear bodies are braided together, as long as it contains at least one linear body of a simple metal or a linear body of a metal alloy, or composite linear body.

[0036] Examples of metals that can be used to form the composite linear body include simple metals such as gold, silver, copper, iron, aluminum, nickel, chromium, tin, and zinc; and alloys containing at least one of these simple metals (such as copper-nickel-phosphorus alloys and copper-iron-phosphorus-zinc alloys).

[0037] Examples of the threads constituting the linear body formed by applying a conductive coating to a thread include threads spun from resins such as nylon and polyester. Examples of conductive coatings include coatings of metals, conductive polymers, carbon materials, etc. The conductive coating can be formed by plating, vapor deposition, etc. A linear body formed by applying a conductive coating to a yarn has good conductivity while maintaining the flexibility of the yarn.

[0038] Among these, the conductive linear body is preferably a metal wire linear body. The use of the metal wire linear bodies makes it easier to obtain a wiring sheet for three-dimensional molding with a lower resistance value. Furthermore, when the wiring sheet for three-dimensional molding is used as a heating element, a wiring sheet for three-dimensional molding with the metal wire linear bodies tends to generate heat quickly, which is preferable.

[0039] [Pseudo seat structure] The pseudo sheet structure is made up of a plurality of conductive linear bodies arranged at intervals, i.e., the pseudo sheet structure is an assembly of a plurality of conductive linear bodies.

[0040] The number of conductive linear members contained in the pseudo sheet structure is 2 or more, preferably 3 to 100, and more preferably 4 to 80.

[0041] When the number of conductive linear members included in the pseudo sheet structure is three or more, the conductive linear members may be arranged at equal intervals or at unequal intervals.

[0042] The interval between the conductive linear bodies is preferably 0.1 to 100 mm, more preferably 1 to 80 mm, and even more preferably 2 to 50 mm. When the spacing between the conductive linear members is within the above range, the conductive linear members are densely packed to a certain extent, so that the resistance of the pseudo-sheet structure can be maintained low. Furthermore, when the wiring sheet for three-dimensional molding is used as a heating element, it becomes easier to obtain a wiring sheet for three-dimensional molding that increases in temperature more uniformly.

[0043] The spacing between the conductive linear members can be determined by observing the conductive linear members of the pseudo sheet structure using a digital microscope.

[0044] The thickness (T3) of the pseudo-sheet structure is preferably 7 to 75 μm, more preferably 8 to 60 μm, and even more preferably 12 to 40 μm. When the cross-sectional shapes of the multiple conductive linear bodies constituting the pseudo sheet structure are all circular with the same diameter, the diameters of the cross-sections of those conductive linear bodies can be assumed to be the thickness (T3) of the pseudo sheet structure. Also, when the cross-sectional shapes of the multiple conductive linear bodies are all circular but the diameters of the cross-sections of those conductive linear bodies are not the same, the largest diameter of the cross-sections of those conductive linear bodies can be assumed to be the thickness (T3) of the pseudo sheet structure. In addition, the cross section of the wiring sheet for three-dimensional formation can be observed with a digital microscope, and a parallelogram containing multiple conductive linear bodies, with its upper and lower sides parallel and its area minimized, can be imagined, and its height (the distance between the upper and lower sides) can be used as the thickness (T3) of the pseudo sheet structure.

[0045] [Embedding layer] The wiring sheet for three-dimensional molding of the present invention has two buried layers. In this specification, when the wiring sheet for three-dimensional molding is placed horizontally, the buried layer located on the lower side is referred to as the "first buried layer" and the buried layer located on the upper side is referred to as the "second buried layer."

[0046] The pseudo sheet structure is sandwiched between the first buried layer and the second buried layer. The wiring sheet for three-dimensional molding has such a layer structure, so that the pseudo sheet structure is stably fixed.

[0047] The storage shear modulus of the first buried layer at 23°C is 1.0 × 10 4 ~3.0×10 6 Pa, preferably 2.0 x 10 4 ~3.0×10 6 Pa, more preferably 5.0 × 10 4 ~3.0×10 5 The storage shear modulus of the second buried layer at 23°C is 1.0 × 10 4 ~3.0×10 6 Pa, preferably 2.0 x 10 4 ~3.0×10 6 Pa, more preferably 5.0 × 10 4 ~3.0×10 5 It is Pa. The storage shear modulus at 23° C. of the first buried layer and the second buried layer can be measured by the method described in the Examples. By having the storage shear modulus at 23°C of the first embedded layer and the second embedded layer within the above range, it is possible to obtain a wiring sheet for three-dimensional molding that reliably fixes the conductive linear body during the three-dimensional molding process and is less likely to have problems with poor appearance after the three-dimensional molding process. That is, the embedding layer is relatively easy to deform at temperatures around room temperature, so the conductive linear objects can be sufficiently embedded and reliably fixed. In a wiring sheet in which the conductive linear objects are sufficiently embedded in the embedding layer, the conductive linear objects are less likely to shift even when a three-dimensional forming process is performed, and traces of the conductive linear objects are not noticeable. The storage shear modulus of the embedding layer at 23°C can be appropriately controlled using known techniques in the field of pressure-sensitive adhesives and adhesives, such as the molecular weight of the resin component constituting the embedding layer or the formation of a crosslinked structure.

[0048] The thickness (T1) of the first buried layer is preferably 3 to 200 μm, more preferably 4 to 150 μm, and even more preferably 5 to 100 μm. The thickness (T2) of the second buried layer is preferably 3 to 200 μm, more preferably 4 to 150 μm, and even more preferably 5 to 100 μm.

[0049] The first and second buried layers may have the same composition or different compositions, but it is preferable that the first and second buried layers have the same composition, as this allows for more efficient production of the wiring sheet for three-dimensional molding.

[0050] The first and second embedding layers are preferably curable. As described above, the embedding layers have a relatively low storage shear modulus at 23°C and are easily deformed. This may result in a problem that the final product after the three-dimensional molding process is also easily deformed. If the first and second buried layers are curable, then by curing these layers after the three-dimensional molding process, deformation in the final product can be suppressed.

[0051] The first and second burying layers can be efficiently formed by using an adhesive or a pressure-sensitive adhesive as a raw material composition.

[0052] The raw material composition used to form the burying layer is not particularly limited as long as it can form a burying layer having the above-mentioned storage shear modulus. Examples of the raw material composition include an acrylic composition (a composition containing an acrylic polymer), a phenoxy composition (a composition containing a phenoxy resin), a urethane composition (a composition containing a urethane polymer), a rubber composition (a composition containing a rubber polymer), a polyester composition (a composition containing a polyester polymer), a silicone composition (a composition containing a silicone polymer), and a polyvinyl ether composition (a composition containing a polyvinyl ether polymer). Among these, acrylic compositions and phenoxy compositions are preferred.

[0053] Examples of acrylic compositions include resin compositions containing acrylic polymers containing repeating units derived from alkyl (meth)acrylates having a linear or branched alkyl group, and acrylic polymers containing repeating units derived from (meth)acrylates having a cyclic structure. Here, the term "(meth)acrylate" is used to refer to both "acrylate" and "methacrylate."

[0054] The acrylic polymer may be a homopolymer or a copolymer. When the acrylic polymer is a copolymer, the form of copolymerization is not particularly limited. The acrylic copolymer may be any of a block copolymer, a random copolymer, or a graft copolymer.

[0055] Among these, the acrylic polymer is preferably an acrylic copolymer containing a repeating unit (a1) derived from an alkyl(meth)acrylate (a1') having a chain alkyl group having 1 to 20 carbon atoms (hereinafter, sometimes referred to as "monomer (a1')") and a repeating unit (a2) derived from a functional group-containing monomer (a2') (hereinafter, sometimes referred to as "monomer (a2')"). The acrylic copolymer may further contain a repeating unit (a3) ​​derived from a monomer (a3') other than the monomer (a1') and the monomer (a2').

[0056] The number of carbon atoms in the chain alkyl group contained in the monomer (a1') is preferably 1 to 12, more preferably 4 to 8, and even more preferably 4 to 6, from the viewpoint of improving adhesive properties. Examples of the monomer (a1') include methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, n-butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, lauryl (meth)acrylate, tridecyl (meth)acrylate, and stearyl (meth)acrylate. Among these monomers (a1'), butyl (meth)acrylate and 2-ethylhexyl (meth)acrylate are preferred, and butyl (meth)acrylate is more preferred. The monomer (a1') can be used alone or in combination of two or more.

[0057] The content of the repeating unit (a1) is preferably 50 to 99.5 mass %, more preferably 55 to 99 mass %, further preferably 60 to 97 mass %, particularly preferably 65 to 95 mass %, based on all repeating units in the acrylic copolymer.

[0058] Examples of the monomer (a2') include hydroxy group-containing monomers, carboxy group-containing monomers, epoxy group-containing monomers, amino group-containing monomers, cyano group-containing monomers, keto group-containing monomers, and alkoxysilyl group-containing monomers. Among these monomers (a2'), hydroxy group-containing monomers and carboxy group-containing monomers are preferred. Examples of the hydroxy group-containing monomer include 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, 3-hydroxybutyl (meth)acrylate, and 4-hydroxybutyl (meth)acrylate. Examples of the carboxy group-containing monomer include (meth)acrylic acid, maleic acid, fumaric acid, and itaconic acid, with (meth)acrylic acid being preferred. Examples of epoxy group-containing monomers include glycidyl (meth)acrylate. Examples of the amino group-containing monomer include diaminoethyl (meth)acrylate. Examples of the cyano group-containing monomer include acrylonitrile. The monomer (a2') can be used alone or in combination of two or more.

[0059] The content of the repeating unit (a2) is preferably 0.1 to 50 mass %, more preferably 0.5 to 40 mass %, further preferably 1.0 to 30 mass %, particularly preferably 1.5 to 20 mass %, based on all repeating units of the acrylic copolymer.

[0060] Examples of the monomer (a3') include (meth)acrylates having a cyclic structure (for example, cyclohexyl (meth)acrylate, benzyl (meth)acrylate, isobornyl (meth)acrylate, dicyclopentanyl (meth)acrylate, dicyclopentenyl (meth)acrylate, dicyclopentenyloxyethyl (meth)acrylate, imide (meth)acrylate, and acryloylmorpholine), vinyl acetate, and styrene. The monomer (a3') can be used alone or in combination of two or more.

[0061] The content of the repeating unit (a3) ​​is preferably 0 to 40 mass %, more preferably 0 to 30 mass %, even more preferably 0 to 25 mass %, and particularly preferably 0 to 20 mass %, based on all repeating units of the acrylic copolymer.

[0062] The weight-average molecular weight (Mw) of the acrylic polymer is usually 50,000 to 800,000, preferably 80,000 to 500,000, and more preferably 100,000 to 450,000. When the weight-average molecular weight of the acrylic polymer is within the above range, the embedding layer may have an appropriate storage shear modulus. The weight average molecular weight (Mw) of the acrylic polymer can be determined as a value converted into standard polystyrene by performing gel permeation chromatography (GPC) using tetrahydrofuran (THF) as a solvent.

[0063] The content of the acrylic polymer in the acrylic composition is usually 60 to 99.9 mass %, and preferably 80 to 99.9 mass %, of the active ingredients of the acrylic composition. In this specification, the active ingredient refers to the components of the composition excluding the solvent.

[0064] The acrylic polymer may be crosslinked with a crosslinking agent. Examples of the crosslinking agent include an epoxy crosslinking agent, an isocyanate crosslinking agent, an aziridine crosslinking agent, and a metal chelate crosslinking agent. When the acrylic copolymer is crosslinked, the functional group derived from the monomer (a2') can be used as a crosslinking point that reacts with the crosslinking agent. By crosslinking the acrylic copolymer with a crosslinking agent, the storage shear modulus of the embedding layer can be efficiently controlled.

[0065] When the acrylic composition contains a crosslinking agent, the content of the crosslinking agent is usually 30% by mass or less, preferably 0.1 to 30% by mass, and more preferably 0.1 to 15% by mass, of the active ingredients of the acrylic composition.

[0066] The acrylic composition may contain an energy ray-curable component. By using an acrylic composition containing an energy ray-curable component, a curable embedding layer can be efficiently formed. Examples of the energy ray-curable component include compounds having two or more ultraviolet-polymerizable functional groups in one molecule, such as polyfunctional (meth)acrylate compounds. Furthermore, a compound having in one molecule a functional group that reacts with the functional group of the monomer (a2') and an energy ray-polymerizable functional group can also be used as the energy ray-curable component.

[0067] The phenoxy-based composition is a resin composition containing a phenoxy resin as a binder resin. Phenoxy resin is a polymer whose main chain has a polyaddition structure of aromatic diol and aromatic diglycidyl ether. In this specification, "phenoxy resin" refers to a polymer having a weight-average molecular weight (Mw) of more than 10,000.

[0068] Examples of the phenoxy resin include bisphenol A type phenoxy resin, bisphenol F type phenoxy resin, bisphenol A-bisphenol F type phenoxy resin, and bisphenol E type phenoxy resin. Phenoxy resins can be obtained by reacting a bisphenol compound or biphenol compound with an epihalohydrin such as epichlorohydrin, or by reacting a bisphenol compound or biphenol compound with a liquid epoxy resin. The phenoxy resins can be used alone or in combination of two or more.

[0069] Commercially available phenoxy resins include those sold under the trade names PKHC, PKHH, and PKHJ (all manufactured by Tomoe Chemical Co., Ltd.), Epicoat 4250, Epicoat 1255HX30, and Epicoat 5580BPX40 (all manufactured by Nippon Kayaku Co., Ltd.), YP-50, YP50S, YP-55, and YP-70 (all manufactured by Nippon Steel Chemical & Material Co., Ltd.), and JER 1256, 4250, YX6954BH30, YX7200B35, and YL7290BH30 (all manufactured by Mitsubishi Chemical Corporation).

[0070] The weight-average molecular weight (Mw) of the phenoxy resin is usually 10,000 to 200,000, preferably 20,000 to 100,000, and more preferably 30,000 to 80,000. When the weight-average molecular weight of the phenoxy resin is within the above range, the embedding layer may have an appropriate storage shear modulus. The weight average molecular weight (Mw) of the phenoxy resin can be determined as a standard polystyrene equivalent value by performing gel permeation chromatography (GPC) using tetrahydrofuran (THF) as a solvent.

[0071] The content of the phenoxy resin in the phenoxy composition is usually 20 to 90 mass %, and preferably 30 to 80 mass %, of the active ingredients of the phenoxy composition.

[0072] The phenoxy-based composition may contain an epoxy resin. In this specification, those having a weight-average molecular weight (Mw) of 10,000 or less are referred to as "epoxy resins" to distinguish them from "phenoxy resins." Examples of epoxy resins include aliphatic epoxy compounds (excluding alicyclic epoxy compounds), aromatic epoxy compounds, and alicyclic epoxy compounds.

[0073] Examples of aliphatic epoxy compounds include 1,4-butanediol diglycidyl ether, neopentyl glycol diglycidyl ether, triglycidyl ether of glycerin, triglycidyl ether of trimethylolpropane, tetraglycidyl ether of sorbitol, hexaglycidyl ether of dipentaerythritol, diglycidyl ether of polyethylene glycol, and diglycidyl ether of polypropylene glycol.

[0074] Examples of aromatic epoxy compounds include glycidyl ethers of bisphenol A, bisphenol F, or compounds obtained by further adding alkylene oxide to these compounds, and epoxy novolac resins; polyglycidyl ethers of aromatic compounds having two or more phenolic hydroxyl groups, such as resorcinol, hydroquinone, and catechol; glycidyl ethers of aromatic compounds having two or more alcoholic hydroxyl groups, such as phenyldimethanol, phenyldiethanol, and phenyldibutanol; and glycidyl esters of polybasic aromatic compounds having two or more carboxylic acids, such as phthalic acid, terephthalic acid, and trimellitic acid.

[0075] Examples of alicyclic epoxy compounds include polyglycidyl ethers of polyhydric alcohols having at least one alicyclic structure, such as dicyclopentadiene dimethanol diglycidyl ether and hydrogenated bisphenol A; and cycloalkene oxide compounds such as cyclohexene oxide and cyclopentene oxide-containing compounds obtained by epoxidizing a cyclohexene ring-containing compound or a cyclopentene ring-containing compound with an oxidizing agent. The epoxy resins can be used alone or in combination of two or more. The molecular weight of the epoxy resin is usually 100 to 5,000, and preferably 200 to 4,000.

[0076] When the phenoxy composition contains an epoxy resin, the content of the epoxy resin is usually 75 mass % or less, preferably 5 to 75 mass %, and more preferably 10 to 50 mass % of the active ingredients of the phenoxy composition.

[0077] When the raw material composition contains a curable component, the raw material composition preferably contains a polymerization initiator. For example, in a raw material composition containing a cationically polymerizable compound such as an epoxy compound, by adding a cationic polymerization initiator, it is possible to form a more efficiently cured embedding layer.

[0078] As the cationic polymerization initiator, a photo-induced cationic polymerization initiator is preferred. When a thermal cationic polymerization initiator is used, there is a risk that a curing reaction may proceed during three-dimensional molding. In this regard, by using a photocationic polymerization initiator, the curing reaction does not proceed during three-dimensional molding, but can proceed after the three-dimensional molding is completed.

[0079] A photocationic polymerization initiator is a compound that generates cationic species when irradiated with ultraviolet light, thereby initiating the curing reaction of a cationic polymerizable compound. It consists of a cationic moiety that absorbs ultraviolet light and an anionic moiety that serves as an acid generating source.

[0080] Examples of the photocationic polymerization initiator include sulfonium salt compounds, iodonium salt compounds, phosphonium salt compounds, ammonium salt compounds, diazonium salt compounds, selenium salt compounds, oxonium salt compounds, etc. Among these, sulfonium salt compounds are preferred because of their excellent compatibility with other components, and aromatic sulfonium salt compounds having an aromatic group are more preferred.

[0081] The sulfonium salt compounds include triphenylsulfonium hexafluorophosphate, triphenylsulfonium hexafluoroantimonate, triphenylsulfonium tetrakis(pentafluorophenyl)borate, 4,4'-bis[diphenylsulfonio]diphenylsulfide-bishexafluorophosphate, 4,4'-bis[di(β-hydroxyethoxy)phenylsulfonio]diphenylsulfide-bishexafluoroantimonate, 7-[di(p-to 7-[di(p-toluyl)sulfonio]-2-isopropylthioxanthone hexafluorophosphate, 7-[di(p-toluyl)sulfonio]-2-isopropylthioxanthone hexafluoroantimonate, 7-[di(p-toluyl)sulfonio]-2-isopropyltetrakis(pentafluorophenyl)borate, phenylcarbonyl-4'-diphenylsulfonio-diphenylsulfide-hexafluorophosphate, phenylcarbonyl-4'-diphenylsulfonio-diphenylsulfide bis(4-fluorophenyl)sulfonium hexafluoroantimonate, 4-tert-butylphenylcarbonyl-4'-diphenylsulfonio-diphenylsulfide-hexafluorophosphate, 4-tert-butylphenylcarbonyl-4'-diphenylsulfonio-diphenylsulfide-hexafluoroantimonate, 4-tert-butylphenylcarbonyl-4'-diphenylsulfonio-diphenylsulfide-tetrakis(pentafluorophenyl)borate, 4-(phenylthio)phenyldiphenylsulfonium hexafluoroantimonate, 4-(phenylthio)phenyldiphenylsulfonium hexafluorophosphate, 4-{4-(2-chlorobenzoyl)phenylthio}phenylbis(4-fluorophenyl)sulfonium hexafluoroantimonate, thiophenyldiphenylsulfonium hexafluoroantimonate halide, 4,4',4''-tri(β-hydroxyethoxyphenyl)sulfonium hexafluoroantimonate, 4,Examples include 4'-bis[diphenylsulfonio]diphenylsulfide-bishexafluoroantimonate, diphenyl[4-(phenylthio)phenyl]sulfonium trifluorotrispentafluoroethylphosphate, tris[4-(4-acetylphenylsulfanyl)phenyl]sulfonium tris[(trifluoromethyl)sulfonyl]methanide, and salts in which the cation moiety is 4-(phenylthio)phenyldiphenylsulfonium and the anion moiety is a phosphorus-based anion to which fluorine and a perfluoroalkyl group are added.

[0082] Examples of iodonium salt compounds include diphenyliodonium tetrakis(pentafluorophenyl)borate, diphenyliodonium hexafluorophosphate, diphenyliodonium hexafluoroantimonate, di(4-nonylphenyl)iodonium hexafluorophosphate, and (tricumyl)iodonium tetrakis(pentafluorophenyl)borate.

[0083] Examples of the phosphonium salt compound include tri-n-butyl(2,5-dihydroxyphenyl)phosphonium bromide and hexadecyltributylphosphonium chloride.

[0084] Examples of the ammonium salt compounds include benzyltrimethylammonium chloride, phenyltributylammonium chloride, and benzyltrimethylammonium bromide.

[0085] These photocationic polymerization initiators can be used alone or in combination of two or more.

[0086] Commercially available photocationic polymerization initiators include Cyracure UVI-6970, Cyracure UVI-6974, Cyracure UVI-6990, and Cyracure UVI-950 (all manufactured by Union Carbide Corporation), Irgacure 250, Irgacure 261, and Irgacure 264 (all manufactured by Chiba Specialty Chemicals), SP-150, SP-151, SP-170, and Optomer SP-171 (all manufactured by ADEKA Corporation), CG-24-61 (manufactured by Chiba Specialty Chemicals), and DAICAT II (manufactured by Daicel), UVAC1590, UVAC1591 (all manufactured by Daicel-Cytec), CI-2064, CI-2639, CI-2624, CI-2481, CI-2734, CI-2855, CI-2823, CI-2758, CIT-1682 (all manufactured by Nippon Soda), PI-2074 (manufactured by Rhodia), FFC509 (manufactured by 3M), BBI-102, BBI-101, BBI-103, MPI-103, TPS-103, MDS -103, DTS-103, NAT-103, NDS-103 (all manufactured by Midori Chemical Co., Ltd.), CD-1010, CD-1011, CD-1012 (manufactured by Sartomer), CPI-100P, CPI-101A, CPI-200K, CPI-310B (all manufactured by San-Apro Co., Ltd.), San-Aid SI-60, San-Aid SI-80, San-Aid SI-100, San-Aid SI-110, San-Aid SI-150 (all manufactured by Sanshin Chemical Industry Co., Ltd.), and the like.

[0087] When the raw material composition contains a cationic photopolymerization initiator, the content of the cationic photopolymerization initiator is usually 0.1 to 10 parts by mass, preferably 0.3 to 8 parts by mass, and more preferably 0.5 to 6 parts by mass, per 100 parts by mass of the cationic polymerizable compound.

[0088] The raw material composition used to form the embedding layer may contain additives such as a tackifier, a silane coupling agent, an antistatic agent, a stabilizer, an antioxidant, a plasticizer, a lubricant, and a coloring pigment, as well as a solvent, within a range that does not impair the effects of the present invention. The content of these may be determined appropriately depending on the purpose.

[0089] The method for forming the buried layer is not particularly limited. For example, the embedding layer can be formed by applying the raw material composition onto a substrate or a release sheet and drying the resulting coating. This substrate and release sheet may ultimately constitute the resin layer of the wiring sheet for three-dimensional molding of the present invention.

[0090] [Resin layer] The wiring sheet for three-dimensional molding of the present invention may have a resin layer adjacent to the embedding layer. In this specification, the resin layer adjacent to the first embedding layer is referred to as the "first resin layer," and the resin layer adjacent to the second embedding layer is referred to as the "second resin layer." In the present invention, the term "resin layer" refers not only to a layer that exists even after the wiring sheet for three-dimensional molding has completed three-dimensional molding and become a product, i.e., a layer (substrate) that is attached in a manner that makes it inseparable from the embedding layer, but also to a layer that exists during the manufacturing or storage of the wiring sheet for three-dimensional molding and is removed during the product manufacturing process (for example, a release sheet, a protective sheet, a process sheet, etc.). The resin layer plays a role in maintaining the shape of the wiring sheet for three-dimensional molding and improving the impact resistance. The thickness of the resin layer is usually 10 to 500 μm, preferably 20 to 300 μm.

[0091] As the resin layer, a resin film is preferably used. Examples of resin films include polymethyl methacrylate resin films, polyethylene films, polypropylene films, polybutene films, polybutadiene films, polymethylpentene films, polyvinyl chloride films, vinyl chloride copolymer films, polyethylene terephthalate films, polyethylene naphthalate films, polybutylene terephthalate films, polyurethane films, ethylene-vinyl acetate copolymer films, ionomer resin films, ethylene-(meth)acrylic acid copolymer films, ethylene-(meth)acrylic acid ester copolymer films, polystyrene films, polycarbonate films, polyether ether ketone films, polyphenylene sulfide films, polyvinylidene fluoride films, polytetrafluoroethylene films, silicone films, and polyimide films.

[0092] When the resin layer is to be removed during the product manufacturing process, the surface of the resin layer that comes into contact with the embedding layer preferably has releasability. As such a resin layer, a resin film having a release layer provided on the surface thereof is preferably used. The release layer can be formed using a known release agent. The thickness of the release layer is not particularly limited, but is usually 0.01 to 2.0 μm, preferably 0.03 to 1.0 μm.

[0093] [Wiring sheet for three-dimensional molding] The wiring sheet for three-dimensional molding of the present invention satisfies the following formula, where the thickness of the first embedded layer is T1, the thickness of the second embedded layer is T2, and the thickness of the pseudo sheet structure is T3.

[0094]

number

[0095] The wiring sheet for three-dimensional molding of the present invention satisfies the above formula, and therefore is less likely to have problems with poor appearance after three-dimensional molding. The value of (T1+T2) / T3 is preferably more than 1 and not more than 8, more preferably more than 1 and not more than 5.

[0096] The method for producing the wiring sheet for three-dimensional molding of the present invention is not particularly limited. For example, two embedding layers are prepared, a pseudo-sheet structure is embedded in one of the embedding layers, and then the other embedding layer is attached on top of the first, thereby obtaining a wiring sheet for three-dimensional molding.

[0097] The wiring sheet for three-dimensional molding of the present invention is suitably used as a material for producing a heating element having a predetermined shape. Examples of uses of the heating element include defoggers and defrosters. [Example]

[0098] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to the following examples. In the following, the "film for forming a resin layer" may be referred to as the "resin layer", and the "adhesive sheet for forming an embedding layer" may be referred to as the "embedding layer".

[0099] [Compounds and materials used in the examples] Acrylic copolymer (A): an acrylic copolymer obtained using n-butyl acrylate / acrylic acid = 90.0 / 10.0 (mass ratio) as raw material monomers, weight average molecular weight (Mw): 410,000 Isocyanate compound (B): Trimethylolpropane-modified tolylene diisocyanate: Toyochem Co., Ltd., product name: BHS8515 Phenoxy resin (C): Mitsubishi Chemical Corporation, product name: YX7200B35 Epoxy compound (D): Epoxy resin having an oxyalkylene group (manufactured by Mitsubishi Chemical Corporation, trade name: YX7400, cyclic ether equivalent: 440 g / eq, (liquid at 25°C)) Epoxy compound (E): Hydrogenated bisphenol A epoxy resin (manufactured by Mitsubishi Chemical Corporation, product name: YX8000, cyclic ether equivalent: 205 g / eq, liquid at 25°C) Photocationic polymerization initiator (F): 4-(phenylthio)phenyldiphenylsulfonium hexafluorophosphate (manufactured by San-Apro Co., Ltd., product name: CPI-100P) Thermal cationic polymerization initiator (G): Sanshin Chemical Industry Co., Ltd., product name: SI-B3 Resin layer (H): PMMA film (manufactured by Sumika Acrylic Sales Co., Ltd., product name: Technoloy S000, thickness 200 μm)

[0100] [Production Example 1] A raw material composition (I) having an active ingredient concentration of 25% by mass was obtained by mixing 100 parts by mass of the acrylic copolymer (A), 0.3 parts by mass of the isocyanate compound (B) (active ingredient), and toluene.

[0101] [Production Example 2] The raw material composition (I) obtained in Production Example 1 was applied to the release-treated surface of a release film (manufactured by Lintec Corporation, product name: SP-PET752150), and the resulting coating was dried at 100°C for 2 minutes to form an embedding layer (Ia) with a thickness of 20 µm. The release-treated surface of another release film (manufactured by Lintec Corporation, product name: SP-PET381031) was attached to the embedding layer (Ia) to produce an embedding layer (Ia) with a release film.

[0102] [Production Example 3] An embedding layer (Ib) with a release film was produced in the same manner as in Production Example 2, except that the thickness of the embedding layer was changed to 15 μm.

[0103] [Production Example 4] An embedding layer (Ic) with a release film was produced in the same manner as in Production Example 2, except that the thickness of the embedding layer was changed to 10 μm.

[0104] [Production Example 5] A raw material composition (II) was obtained in the same manner as in Production Example 1, except that the amount of the isocyanate compound (B) was changed to 5 parts by mass (active ingredient).

[0105] [Production Example 6] The raw material composition (II) obtained in Production Example 5 was applied to the release-treated surface of a release film (manufactured by Lintec Corporation, product name: SP-PET752150), and the resulting coating was dried at 100°C for 2 minutes to form an embedding layer (IIa) with a thickness of 30 µm. The release-treated surface of another release film (manufactured by Lintec Corporation, product name: SP-PET381031) was attached to the embedding layer (IIa) to produce an embedding layer (IIa) with a release film.

[0106] [Production Example 7] An embedding layer (IIb) with a release film was produced in the same manner as in Production Example 6, except that the thickness of the embedding layer was changed to 20 μm.

[0107] [Production Example 8] An embedding layer (IIc) with a release film was produced in the same manner as in Production Example 6, except that the thickness of the embedding layer was changed to 10 μm.

[0108] [Production Example 9] An embedding layer (IId) with a release film was produced in the same manner as in Production Example 6, except that the thickness of the embedding layer was changed to 5 μm.

[0109] [Production Example 10] A raw material composition (III) having an active ingredient concentration of 50% by mass was obtained by mixing 100 parts by mass of a phenoxy resin (C), 60 parts by mass of an epoxy compound (D), 2 parts by mass of a photocationic polymerization initiator (F), and methyl ethyl ketone.

[0110] [Production Example 11] The raw material composition (III) obtained in Production Example 10 was applied to the release-treated surface of a release film (manufactured by Lintec Corporation, product name: SP-PET752150), and the resulting coating was dried at 100°C for 2 minutes to form an embedding layer (IIIa) with a thickness of 25 µm. The release-treated surface of another release film (manufactured by Lintec Corporation, product name: SP-PET381031) was attached to the embedding layer (IIIa) to produce an embedding layer (IIIa) with a release film.

[0111] [Production Example 12] An embedding layer (IIIb) with a release film was produced in the same manner as in Production Example 11, except that the thickness of the embedding layer was changed to 20 μm.

[0112] [Production Example 13] A high-pressure mercury lamp manufactured by Eye Graphics was used, with an illumination intensity of 200 mW / cm 2 , cumulative light intensity 1000mJ / cm 2 Under the conditions above, the embedding layer (IIIa) with a release film obtained in Production Example 11 was irradiated with UV light to obtain an embedding layer (IIIc) with a release film.

[0113] [Production Example 14] A high-pressure mercury lamp manufactured by Eye Graphics was used, with an illumination intensity of 200 mW / cm 2 , cumulative light intensity 1000mJ / cm 2 The embedding layer (IIIb) with a release film obtained in Production Example 12 was irradiated with UV light under the conditions above to obtain an embedding layer (IIId) with a release film.

[0114] [Production Example 15] 100 parts by mass of phenoxy resin (C), 200 parts by mass of epoxy compound (E), 8 parts by mass of thermal cationic polymerization initiator (G), and methyl ethyl ketone were mixed to obtain raw material composition (IV) with an active ingredient concentration of 50% by mass.

[0115] [Production Example 16] The raw material composition (IV) obtained in Production Example 15 was applied to the release-treated surface of a release film (manufactured by Lintec Corporation, product name: SP-PET752150), and the resulting coating was dried at 100°C for 2 minutes to form an embedding layer (IVa) with a thickness of 20 µm. The release-treated surface of another release film (manufactured by Lintec Corporation, product name: SP-PET381031) was attached to the embedding layer (IVa) to produce an embedding layer (IVa) with a release film.

[0116] [Measurement of storage shear modulus (G')] In accordance with JIS K7244-6, the storage shear modulus (G') was measured by the torsional shear method using a viscoelasticity measuring device (manufactured by Anton Paar, product name: MCR302) under the conditions of a frequency of 1 Hz, a test start temperature of 0°C, a test end temperature of 120°C, and a heating rate of 3°C / min. The measurement samples were obtained by different methods depending on the properties of the raw material compositions, the details of which are shown below.

[0117] (Raw material composition (I)) A plurality of embedding layers (Ia) with release films obtained in Production Example 2 were prepared, and after peeling off the release films, the embedding layers (Ia) were stacked to obtain a laminate with a thickness of about 0.5 mm. The resulting laminate was then stored for one week in an environment at a temperature of 23°C and a relative humidity of 50% for seasoning, and then punched out into a cylindrical object with a diameter of 8 mm (height of 0.5 mm) to be used as a measurement sample.

[0118] (Raw material composition (II)) A plurality of embedding layers (IIa) with release films obtained in Production Example 6 were prepared, and after peeling off the release films, embedding layers (IIa) were stacked to obtain a laminate with a thickness of about 0.5 mm. The resulting laminate was then stored for one week in an environment at a temperature of 23°C and a relative humidity of 50% for seasoning, and then punched out into a cylindrical object with a diameter of 8 mm (height of 0.5 mm) to be used as a measurement sample.

[0119] (Raw material composition (III)) A plurality of embedding layers (IIIa) with release films obtained in Production Example 10 were prepared, and after peeling off the release films, embedding layers (IIIa) were stacked to obtain a laminate with a thickness of about 0.5 mm. For raw material composition (III), two of these laminates were prepared, and one was punched out as it was to form a cylindrical body with a diameter of 8 mm (height of 0.5 mm) which was used as a measurement sample. The other uses a high-pressure mercury lamp manufactured by Eye Graphics, with an illumination intensity of 200 mW / cm 2 , cumulative light intensity 1000mJ / cm 2 After UV irradiation under the conditions, a cylindrical body with a diameter of 8 mm (height of 0.5 mm) was punched out and used as a measurement sample.

[0120] (Raw material composition (IV)) A plurality of embedding layers (IVa) with release films obtained in Production Example 13 were prepared, and after peeling off the release films, embedding layers (IVa) were stacked to obtain a laminate with a thickness of about 0.5 mm. The resulting laminate was then subjected to a heat curing treatment at 100° C. for 60 minutes, and then punched out into a cylindrical body with a diameter of 8 mm (height of 0.5 mm) to be used as a measurement sample.

[0121] Table 1 shows the composition of the raw material composition, the conditions for preparing the measurement sample, and the measurement results of the storage shear modulus (G').

[0122] [Table 1]

[0123] Example 1 The release film on one side of the embedding layer (Ia) with release film obtained in Production Example 2 (which had been stored for one week in an environment of 23°C and 50% relative humidity to be seasoned) was peeled off, and the exposed embedding layer (Ia) and resin layer (H) were laminated together under conditions of 23°C and 0.5 MPa to obtain a laminate with a layer structure of "resin layer (H) / embedding layer (Ia) / release film." Next, the release film of this laminate was peeled off and removed, and the remaining laminate was wrapped around a drum member with a rubber outer periphery with the embedding layer (Ia) facing outward, and then fixed with double-sided tape. A silver-plated tungsten wire (diameter 14 μm, manufactured by Tokusai Corporation, product name: Ag(0.1)-TWG, hereinafter referred to as "wire") was wound around a bobbin, and then the wire was attached to the surface of the embedded layer (Ia) located near the end of the drum member. The wire was then unwound and wound around the drum member. In this process, the drum member was vibrated in the drum axial direction while the wire was wound, so that the wound wire formed a wavy shape. In this way, multiple wires were provided on the surface of the buried layer (Ia) to form a pseudo-sheet structure 14 μm thick consisting of multiple wires arranged at equal intervals, thereby obtaining a buried layer (Ia) having a pseudo-sheet structure. Next, the laminate with the layer structure of "resin layer (H) / embedded layer (Ia) with pseudo-sheet structure" was cut into a 200mm x 300mm rectangle (the wires extended in the long side direction), and a "wiring sheet manufacturing intermediate for three-dimensional molding" with a pseudo-sheet structure consisting of 10 wires was produced. In this wiring sheet manufacturing intermediate for three-dimensional molding, the wires were arranged at equal intervals of 5mm. The wavelength of the wavy wires was 5.5mm, and the amplitude was 1.5mm.

[0124] The release film on one side of the embedded layer (Ia) with release film obtained in Production Example 2 (which had been stored for one week in an environment of 23°C and 50% relative humidity to be seasoned) was peeled off, and the exposed embedded layer (Ia) and the embedded layer (Ia) having the pseudo-sheet structure of the ``manufacturing intermediate of the wiring sheet for three-dimensional molding'' were laminated together under conditions of 23°C and 0.5 MPa to obtain a wiring sheet for three-dimensional molding having a layer structure of ``resin layer (H) / embedded layer (Ia) / pseudo-sheet structure / embedded layer (Ia) / release film.''

[0125] [Examples 2 to 5, Comparative Examples 1 to 3] A wiring sheet for three-dimensional molding was obtained in the same manner as in Example 1, except that the embedding layer and resin layer were changed to those shown in Table 2. In Table 2, the pseudo-sheet structure is omitted. In addition, the buried layers (Ib) to (Ic) and the buried layers (IIa) to (IId) were stored for one week in an environment of 23°C and a relative humidity of 50% and seasoned, and the buried layer (IVa) was heat-cured at 100°C for 60 minutes.

[0126] [3D vacuum molding (TOM molding)] The obtained wiring sheet for three-dimensional molding was attached to an ellipsoidal polycarbonate adherend measuring 10 cm wide, 15 cm long, and 2 cm high at the center, by the TOM molding method. The TOM molding was carried out at 120°C using a TOM molding machine manufactured by SIBE AUTOMATION. For the wiring sheets for three-dimensional molding obtained in Examples 1, 4, and 5 and Comparative Example 3, the release film was peeled off and removed, and the sheets were stacked so that the exposed embedded layer and the adherend were in contact with each other, and TOM molding was performed.For the wiring sheets for three-dimensional molding obtained in Examples 2 and 3 and Comparative Examples 1 and 2, the sheets were stacked so that the resin layer (H) and the adherend were in contact with each other, and TOM molding was performed. The obtained molded product was observed under a digital microscope, and a rating of "good" was given to a product that was molded without any defects in appearance, and a rating of "poor" was given to a product that had defects such as hollow spaces around the wire.

[0127] [Table 2]

[0128] By using the wiring sheets for three-dimensional formation of Examples 1 to 5, three-dimensional forming processing can be performed without causing any defects in appearance. On the other hand, when the wiring sheets of Comparative Examples 1 and 3 were used, the elastic modulus of the embedding layer was too high, so the wires were not embedded sufficiently, and cavities were observed due to the movement of the wires during the three-dimensional molding process. Furthermore, when the wiring sheet of Comparative Example 2 was used, the buried layer did not have a sufficient thickness, so the wires were not buried sufficiently, and cavities were observed due to the wires moving during the three-dimensional molding process. [Explanation of symbols]

[0129] 100, 200, 300... Three-dimensional molding wiring sheet 1a, 1b, 1c... Conductive linear body 2a, 2b, 2c... Pseudo sheet structure 3a, 3b, 3c... First buried layer 4a, 4b, 4c...Second buried layer 5b, 5c: First resin layer 6c...Second resin layer

Claims

1. A wiring sheet for three-dimensional molding, comprising a pseudo-sheet structure made up of a plurality of conductive linear bodies arranged at intervals and sandwiched between a first buried layer and a second buried layer, the conductive linear body has a wave shape in a plan view, The storage shear modulus at 23°C of the first buried layer and the second buried layer is 1.3 × 10 to 3.0 × 10 ６ Pa, The thickness of the first buried layer is T １ , the thickness of the second buried layer is T ２ , the thickness of the pseudo-sheet structure is T ３ When the above formula is satisfied, the wiring sheet for three-dimensional molding satisfies the following formula: [Equation 1]

2. The wiring sheet for three-dimensional molding according to claim 1, wherein the cross-sectional shape of the conductive linear body is a circle having a diameter of 7 to 75 μm.

3. The wiring sheet for three-dimensional molding according to claim 1 or 2, wherein the first buried layer and the second buried layer have the same composition.

4. The wiring sheet for three-dimensional molding according to any one of claims 1 to 3, wherein the first embedding layer and the second embedding layer are curable.

5. The wiring sheet for three-dimensional molding according to any one of claims 1 to 4, which has a first resin layer adjacent to the first embedded layer and / or a second resin layer adjacent to the second embedded layer.

6. The wiring sheet for three-dimensional molding according to claim 5, wherein the surface of the first resin layer facing the first buried layer and / or the surface of the second resin layer facing the second buried layer has peelability.

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