CN114746270A - Laminate, printed wiring board, flexible printed wiring board, electromagnetic wave shield, and molded article - Google Patents

Abstract

The invention provides a laminated body which can be manufactured by a simple method without roughening the surface of a support body and has excellent adhesion between the support body and a metal layer (metal plating layer) after a long-term heat resistance test, and a printed wiring board, a flexible printed wiring board and a molded product using the laminated body. The present invention uses a laminate in which a primer layer (B) and a metal particle layer (C) are laminated in this order on a support (a), wherein the primer layer (B) is a layer containing a primer resin (B1) and silica particles (B2) treated with a silane coupling agent.

Description

Laminate, printed wiring board, flexible printed wiring board, electromagnetic wave shield, and molded article

Technical Field

The present invention relates to a laminate, a printed wiring board, a flexible printed wiring board, an electromagnetic wave shield, and a molded article.

Background

With the miniaturization and high speed of electronic devices, there is a demand for higher density and higher performance of printed wiring boards, and in order to meet the demand, printed wiring boards having a sufficiently thin conductive layer (metal layer) with a smooth surface are being sought. As a material constituting the printed wiring board, a flexible copper clad laminate (hereinafter, referred to as "FCCL") is known. FCCL is mainly produced by a method of laminating a heat-resistant polymer film and a copper foil.

However, in the FCCL using the copper foil, since the copper foil wound in a roll shape is pulled out and the insulating polymer film is laminated or the insulating polymer solution is applied, the copper foil cannot be made sufficiently thin in terms of handling. Furthermore, since the surface of the copper foil must be roughened in order to improve the adhesion to the polymer film, there is a problem that transmission loss occurs in the field of high frequency (GHz band) and high transmission speed (several tens of Gbps) required for high density and high performance of the printed wiring board.

As a method for making the copper layer of FCCL thin, there is proposed a method in which a metal thin film is formed on the surface of a polyimide film by a vapor deposition method or a sputtering method, and then copper is formed on the metal thin film by an electrolytic plating method, an electroless plating method, or a combination of both (for example, see patent document 1). However, in the above method, since a vapor deposition method or a sputtering method is used for forming a metal thin film, a large-scale vacuum apparatus is required, and there is a problem that the size of a substrate is limited in the apparatus.

Therefore, a laminate having sufficient adhesion to a support such as a polymer film without roughening the surface of a metal layer such as a copper foil and capable of being produced by a simple method without requiring a large-scale vacuum equipment in forming the metal layer is desired.

In addition, conventionally, as decorative plating on plastic molded articles, the metal plating is used for mobile phones, personal computers, mirrors, containers, various switches, shower heads, and the like. The support for these applications is limited to acrylonitrile-butadiene-styrene copolymer (hereinafter, abbreviated as "acrylonitrile butadiene styrene, ABS") or polymer alloy of ABS and polycarbonate (hereinafter, abbreviated as "acrylonitrile butadiene styrene polycarbonate, ABS-PC"). The reason for this is that in order to secure adhesion between the substrate and the plating film, it is necessary to roughen the surface of the substrate, and in the case of ABS, for example, it is possible to roughen the surface by etching and removing polybutadiene components with a strong oxidizing agent such as hexavalent chromic acid or permanganic acid. However, hexavalent chromic acid and the like are preferably not used because they are environmentally-friendly substances, and alternative methods have been developed (for example, see patent document 2).

In this way, in plating for the purpose of decoration or the like on plastic molded articles, it is desired to obtain a plating film having excellent adhesion even to other types of plastics and to reduce the amount of environmental load substances used, without limiting the substrate to ABS or ABS-PC.

Documents of the prior art

Patent document

Patent document 1: japanese patent laid-open No. 2015-118044

Patent document 2: japanese patent No. 5830807

Disclosure of Invention

Problems to be solved by the invention

The present invention addresses the problem of providing a laminate that can be produced by a simple method without roughening the surface of a support and that has excellent adhesion between the support and a metal layer (metal plating layer) even after a long-term heat resistance test, and a printed wiring board, a flexible printed wiring board, and a molded article using the laminate.

Means for solving the problems

The present inventors have made extensive studies to solve the above problems, and as a result, have found that a laminate in which a layer containing an undercoat resin and silica particles is provided as an undercoat layer on a support and a metal layer formed of metal particles and a metal plating layer are sequentially laminated thereon can solve the above problems, thereby completing the present invention.

That is, the present invention provides a laminate in which a primer layer (B) and a metal particle layer (C) are sequentially laminated on a support (a), wherein the primer layer (B) is a layer containing a primer resin (B1) and silica particles (B2), and a printed wiring board, a flexible printed wiring board, and a molded article using the laminate.

ADVANTAGEOUS EFFECTS OF INVENTION

The laminate of the present invention is a laminate having excellent adhesion between a support and a metal layer (metal plating layer) without roughening the surface of the support. The laminate is a laminate having a sufficiently thin metal layer with a smooth surface without using a large-scale vacuum apparatus when the metal layer is made thin. Further, the laminate was excellent in adhesion force even after the heat resistance test.

The laminate of the present invention can be suitably used as electronic components such as a printed wiring board, a flexible printed wiring board, a conductive film for a touch panel, a metal mesh for a touch panel, an organic solar cell, an organic Electroluminescence (EL) element, an organic transistor, a Radio Frequency Identification (RFID) for an Integrated Circuit (IC) card, an electromagnetic wave shield, a Light Emitting Diode (LED) lighting substrate, and a digital signage by patterning the metal layer. In particular, it is most suitable for use in flexible printed wiring boards such as FCCL.

Further, by applying the present invention to molded articles, electronic members such as connectors, electrical components, electric motor peripheral components, and battery components that can be suitably used for connecting wires for optical communication and the like; decorative parts for automobiles, lamp reflectors, cellular phones, personal computers, mirrors, containers, home appliances, various switches, faucet parts, shower heads, and the like.

Detailed Description

The laminate of the present invention is a laminate in which a primer layer (B), a metal particle layer (C), and a metal plating layer (D) are sequentially laminated on a support (a), wherein the primer layer (B) is a layer containing a primer resin (B1) and silica particles (B2).

The laminate of the present invention may be one in which a primer layer (B) or the like is sequentially laminated on one surface of the support (a), or may be one in which a primer layer (B) or the like is sequentially laminated on both surfaces of the support (a).

Examples of the support (a) include: including polyimide, transparent polyimide, polyamideimide, polyamide, polyethylene terephthalate, polyethylene naphthalate, polycarbonate, acrylonitrile-butadiene-styrene (ABS) resin, polymer alloy of ABS and polycarbonate, acrylic resin such as poly (methyl (meth) acrylate), polytetrafluoroethylene, tetrafluoroethylene perfluoroalkyl vinyl ether copolymer, tetrafluoroethylene-hexafluoropropylene copolymer, tetrafluoroethylene-ethylene copolymer, vinylidene fluoride resin, chlorotrifluoroethylene-ethylene copolymer, tetrafluoroethylene-perfluorodioxole copolymer, vinyl fluoride resin, polyvinylidene fluoride, polyvinyl chloride, polyvinylidene chloride, polyvinyl alcohol, polycarbonate, polyethylene, polypropylene, polyurethane, liquid crystal polymer (liquid crystal polymer, LCP), Polyetheretherketone (PEEK), polyphenylene sulfide (PPS), polyphenylsulfone (PPSU), epoxy resin, cellulose nanofiber, a support of silicon, ceramics, glass, or the like, a support including a porous material thereof, a support including a metal such as a steel plate, copper, or the like, a support having a surface thereof subjected to vapor deposition treatment such as silicon carbide, diamond-like carbon, aluminum, copper, titanium, or the like, and the like.

When the laminate of the present invention is used for a printed wiring board or the like, the support (a) is preferably a support made of polyimide, transparent polyimide, polytetrafluoroethylene, a tetrafluoroethylene-ethylene copolymer, polyethylene terephthalate, polyethylene naphthalate, a Liquid Crystal Polymer (LCP), polyether ether ketone (PEEK), glass, cellulose nanofibers, or the like.

When the laminate of the present invention is used for a flexible printed wiring board or the like, the support (a) is preferably a film-like or sheet-like support having flexibility that allows bending.

When the support (A) is in the form of a film or a sheet, the thickness thereof is preferably in the range of 1 to 5,000. mu.m, more preferably in the range of 1 to 300. mu.m, and still more preferably in the range of 1 to 200. mu.m.

In addition, in order to further improve the adhesion between the support (a) and the undercoat layer (B) described later, if necessary, fine irregularities are formed on the surface of the support (a) to such an extent that smoothness is not lost, dirt adhering to the surface is washed away, or a surface treatment is performed for introducing a functional group such as a hydroxyl group, a carbonyl group, or a carboxyl group. Specifically, there may be mentioned: a plasma discharge treatment such as a corona discharge treatment, a dry treatment such as an ultraviolet treatment, a wet treatment using water, an aqueous solution of an acid-base or the like, an organic solvent or the like, or the like.

The undercoat layer (B) is a layer containing an undercoat resin (B1) and silica particles (B2).

Examples of the primer resin (b1) include: urethane resins, acrylic resins, core-shell type composite resins in which a urethane resin is a shell and an acrylic resin is a core, epoxy resins, imide resins, amide resins, melamine resins, phenol resins, urea-formaldehyde resins, blocked isocyanates obtained by reacting a blocking agent such as phenol with polyisocyanate, polyvinyl alcohol, polyvinyl pyrrolidone, and the like. The core-shell type composite resin having a urethane resin as a shell and an acrylic resin as a core is obtained by polymerizing an acrylic monomer in the presence of a urethane resin, for example. One kind of these resins may be used, or two or more kinds may be used in combination.

Among the resins for forming the undercoat layer (B), it is preferable to use a resin containing an aminotriazine-modified novolak resin (B1-1).

The aminotriazine-modified novolak resin (b1-1) is a novolak resin in which an aminotriazine ring structure and a phenol structure are bonded via a methylene group. The aminotriazine-modified novolak resin (b1-1) can be obtained, for example, by subjecting an aminotriazine compound such as melamine, benzoguanamine, or acetoguanamine and a phenol compound such as phenol, cresol, butylphenol, bisphenol a, phenylphenol, naphthol, or resorcinol and formaldehyde to a co-condensation reaction in the vicinity of neutral in the presence or absence of a weakly basic catalyst such as an alkylamine, or by reacting an alkyl ether compound of an aminotriazine compound such as methyl etherified melamine with the phenol compound.

The aminotriazine-modified novolak resin (b1-1) preferably has substantially no methylol group. The aminotriazine-modified novolak resin (b1-1) may contain a molecule in which only an aminotriazine structure is methylene-bonded, a molecule in which only a phenol structure is methylene-bonded, and the like, which are generated as by-products during the production thereof. Further, some amount of unreacted raw materials may be contained.

Examples of the phenol structure include a phenol residue, a cresol residue, a butyl phenol residue, a bisphenol a residue, a phenylphenol residue, a naphthol residue, and a resorcinol residue. The residue herein refers to a structure in which at least one of hydrogen atoms bonded to carbon bonds of an aromatic ring is removed. For example, in the case of phenol, it refers to hydroxyphenyl groups.

Examples of the triazine structure include structures derived from aminotriazine compounds such as melamine, benzoguanamine, and acetoguanamine.

The phenol structure and the triazine structure may be used singly or in combination of two or more. In addition, in order to further improve the adhesion, the phenol structure is preferably a phenol residue, and the triazine structure is preferably a structure derived from melamine.

Further, the hydroxyl value of the aminotriazine-modified novolak resin (b1-1) is preferably in the range of 50 to 200mgKOH/g, more preferably in the range of 80 to 180mgKOH/g, and still more preferably in the range of 100 to 150mgKOH/g, from the viewpoint of further improving the adhesion.

One or a combination of two or more of the aminotriazine-modified novolak resins (b1-1) may be used.

When the aminotriazine-ring-containing compound (b1) is an aminotriazine-modified novolak resin (b1-1), it is preferable to use an epoxy resin (b1-2) in combination.

Examples of the epoxy resin (b1-2) include: bisphenol a-type epoxy resins, bisphenol F-type epoxy resins, biphenyl-type epoxy resins, cresol novolac-type epoxy resins, phenol novolac-type epoxy resins, bisphenol a novolac-type epoxy resins, alcohol ether-type epoxy resins, tetrabromobisphenol a-type epoxy resins, naphthalene-type epoxy resins, phosphorus-containing epoxy compounds having a structure derived from a 9, 10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxo derivative, epoxy resins having a structure derived from a dicyclopentadiene derivative, epoxides of fats and oils such as epoxidized soybean oil, and the like. One kind of these epoxy resins may be used, or two or more kinds thereof may be used in combination.

Among the epoxy resins (b1-2), bisphenol a type epoxy resins, bisphenol F type epoxy resins, biphenyl type epoxy resins, cresol novolac type epoxy resins, phenol novolac type epoxy resins, bisphenol a novolac type epoxy resins are preferable, and bisphenol a type epoxy resins are particularly preferable, from the viewpoint of further improving the adhesiveness.

In addition, the epoxy equivalent of the epoxy resin (b1-2) is preferably in the range of 100 g/equivalent to 300 g/equivalent, more preferably in the range of 120 g/equivalent to 250 g/equivalent, and still more preferably in the range of 150 g/equivalent to 200 g/equivalent, in order to further improve the adhesiveness.

When the primer layer (B) is a layer containing an aminotriazine-modified novolak resin (B1-1) and an epoxy resin (B1-2), the molar ratio [ (x)/(y) ] of the phenolic hydroxyl group (x) in the aminotriazine-modified novolak resin (B1-1) to the epoxy group (y) in the epoxy resin (B1-2) is preferably in the range of 0.1 to 5, more preferably in the range of 0.2 to 3, and still more preferably in the range of 0.3 to 2, in terms of further improving the adhesion.

In order to promote the reaction of the aminotriazine-modified novolak resin (b1-1) and the epoxy resin (b1-2), a hardening accelerator may also be used in combination. Examples of the hardening accelerator include amine compounds having a primary amino group, a secondary amino group, or a tertiary amino group. As the amine compound, any of aliphatic, alicyclic, and aromatic compounds may be used. Further, as the hardening accelerator, thiol, acid anhydride, acid boron fluoride, boric acid ester, organic hydrazide, lewis acid, organometallic compound, onium salt, cationic compound, and the like can be used.

As the silica particles (b2), either natural silica particles produced from natural raw materials or synthetic silica particles produced by chemical synthesis may be used. The silica particles (b2) may be silica particles dispersed in water or an organic solvent, or may be used as a slurry or a colloidal solution in which silica particles are dispersed in advance.

When the silica particles (b2) are used for electronic applications, it is preferable to use particles containing less impurities. Examples of the impurities include sodium ions, potassium ions, iron ions, aluminum ions, and chloride ions.

The silica particles (b2) are not particularly limited, but commercially available products that can be used include, for example: SFP series or UFP series (UFP-30, UFP-40, SFP-20M, SFP-30M, SFP-130MC, SFP-120MC, SFP-30MHE, UFP-30HH) manufactured by Danka (Denka) corporation, FB series (FB-5D, FB-8S, FB-15D, FB-20D, FB-40R) manufactured by natural method; sertex (Snowtex) series (ST-XS, ST-OXS, ST-NXS, ST-CXS, ST-S, ST-OS, ST-NS, ST-30, ST-O, ST-N, ST-C, ST-AK, ST-50-T, ST-O-40, ST-CM, ST-30L, ST-OL, ST-AK-L, ST-YL, ST-OYL, ST-AK-YL, ST-ZL, MP-1040, MP-2040, MP-4540M, ST-UP, ST-OUP, ST-PS-S, ST-PS-SO, ST-PS-M, ST-PS-MO) as colloidal solutions with water as a dispersing medium manufactured by Nissan chemical Co., Ltd, Series of organic silica sols (methanol silica sol, MA-ST-M, MA-ST-L, IPA-ST, IPA-ST-L, IPAST-ZL, IPA-ST-UP, EG-ST, NPC-ST-30, PGM-ST, DMAC-ST, MEK-ST-40, MEK-ST-L, MEK-ST-ZL, MEK-ST-UP, MIBK-ST-L, CHO-ST-M, EAC-ST, PMA-ST, TOL-ST, MEK-AC-2140Z, MEK-AC-4130Y, MEK-AC-5140Z, PMG-AC-2140Y, PGM-AC-4130Y, MIBK-AC-2140Z, MEK-ST-T-40, and a colloidal solution using an organic solvent as a dispersion medium, MIBK-SD-L, MEK-EC-2130Y, EP-M2130Y); SO-C types (SO-C1, SO-C2, SO-C4, SO-C5, SO-C6) and SO-E types (SO-E1, SO-E2, SO-E3, SO-E4, SOE5, SO-E6) manufactured by Admadethan technologies (Admatechs) Ltd.

In the present invention, the surfaces of the silica particles (b2) are treated with a silane coupling agent in order to impart dispersibility or affinity to a solvent or the undercoating resin (b1) and high adhesion to the support or the metal particle layer (C) to the silica particles (b 2). The silane coupling agent is not particularly limited, and examples thereof include: epoxysilanes, aminosilanes, vinylsilanes, mercaptosilanes, etc. In addition, after the surface of the silica particles (b2) is treated with a silane coupling agent, a resin may be attached to the surface of the silica particles (b2) treated with a silane coupling agent for the purpose of further improving dispersibility or affinity with the undercoat resin (b 1). Examples of the resin to be attached include: acrylic resin, epoxy resin, urethane resin, polyester resin, etc., but it is preferable to use the same kind of resin as the undercoat resin (b 1).

Examples of the epoxy silane include: 2- (3, 4-epoxycyclohexyl) ethyltrialkoxymethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, 8-glycidooctytrimethoxysilane, polyfunctional silane coupling agents having an organic main chain and a plurality of alkoxysilane groups and epoxy groups (for example, "X-12-981S" or "X-12-984S" manufactured by shin-Etsu chemical Co., Ltd.), and polyfunctional silane coupling agents having a siloxane main chain and a plurality of epoxy groups (for example, "KR-516" manufactured by shin-Etsu chemical Co., Ltd., "KR-516"), "KR-517", etc.), etc. Among these silane coupling agents, an alicyclic structure is preferable, and specifically, 2- (3, 4-epoxycyclohexyl) ethyltrimethoxysilane is preferable.

Examples of the aminosilane include: n-2- (aminoethyl) -3-aminopropylmethyldimethoxysilane, N-2- (aminoethyl) -3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-triethoxysilyl-N- (1, 3-dimethyl-butylene) propylamine, N-phenyl-3-aminopropyltrimethoxysilane, hydrochloride of N- (vinylbenzyl) -2-aminoethyl-3-aminopropyltrimethoxysilane, N-2- (aminoethyl) -8-aminooctyltrimethoxysilane, amino-protecting silane coupling agents (e.g., "KBE-9103P" (ketoimine type) manufactured by shin-Etsu chemical industries, Ltd.), "X-12-1172 ES" (aldimine type), a polyfunctional silane coupling agent having an organic chain as a main chain and having a plurality of alkoxysilane groups and amino groups (for example, "X-12-972F" manufactured by shin-Etsu chemical Co., Ltd.), and the like.

The vinyl silane means a silane compound having a double bond in the present invention. Examples of the silane coupling agent having a vinyl group include: vinyltrimethoxysilane, vinyltriethoxysilane, 7-octenyltrimethoxysilane, and a polyfunctional silane coupling agent having a siloxane chain as its main chain and having a plurality of vinyl groups and phenyl groups (for example, "KR-511" manufactured by shin-Etsu chemical industries, Ltd.). Examples of the silane compound having a double bond include acryl silane, methacryl silane, and styrene silane.

As the acryl silane, there can be mentioned: 3-acryloxypropyltrimethoxysilane, a polyfunctional silane coupling agent having an organic main chain and a plurality of alkoxysilane groups and acrylic groups (for example, "X-12-1048" or "X-12-1050" manufactured by shin-Etsu chemical Co., Ltd.), a polyfunctional silane coupling agent having a siloxane main chain and a plurality of acrylic groups and methyl groups (for example, "KR-513" manufactured by shin-Etsu chemical Co., Ltd.), and the like.

As the methacrylic silane, there can be mentioned: 3-methacryloxypropylmethyldimethoxysilane, 3-methacryloxypropylmethyldiethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropyltriethoxysilane, 8-methacryloxyoctyltrimethoxysilane, and polyfunctional silane coupling agents having a siloxane chain as the main chain and having a plurality of methacrylic groups and methyl groups (for example, "KR-503" manufactured by shin-Etsu chemical industries, Ltd.), and the like.

Examples of the styrylsilane include p-styryltrimethoxysilane.

Examples of the mercaptosilane include: 3-mercaptopropylmethyldimethoxysilane, 3-mercaptopropyltrimethoxysilane, polyfunctional silane coupling agents having an organic main chain and a plurality of alkoxysilyl groups and mercapto groups (for example, "X-12-1154" and "X-12-1156" manufactured by shin-Etsu chemical Co., Ltd.), polyfunctional silane coupling agents having a siloxane main chain and a plurality of mercapto groups (for example, "KR-518" and "KR-519" manufactured by shin-Etsu chemical Co., Ltd.), mercapto group-protected silane coupling agents (for example, "X-12-1056 ES" manufactured by shin-Etsu chemical Co., Ltd.), and the like.

Examples of the other silane coupling agent include: 3-ureidopropyltrialkoxysilane, tris- (trimethoxysilylpropyl) isocyanurate, tris- (triethoxysilylpropyl) isocyanurate, 3-isocyanatopropyltriethoxysilane, 3-trimethoxysilylpropylsuccinic anhydride, and a polyfunctional silane coupling agent having an organic main chain and a plurality of alkoxysilane groups and isocyanate groups (for example, "X-12-1159L" manufactured by shin-Etsu chemical industries, Ltd.), and the like.

Among the silane coupling agents, epoxysilane, aminosilane and methacrylsilane are preferable, and epoxysilane is more preferable.

In order to further improve the adhesion, the content of the silica particles (B2) in the undercoat layer (B) is preferably in the range of 1 to 400 parts by mass with respect to 100 parts by mass of the undercoat resin (B1). In addition, in order to further improve the heat-resistant adhesion after the heat resistance test, the content of the silica particles (B2) in the undercoat layer (B) is preferably in the range of 5 to 200 parts by mass, more preferably in the range of 8 to 100 parts by mass, and still more preferably in the range of 10 to 80 parts by mass, with respect to 100 parts by mass of the undercoat resin (B1).

The average particle diameter of the silica particles (b2) is preferably in the range of 0.001 to 0.5. mu.m, more preferably in the range of 0.01 to 0.1. mu.m, and still more preferably in the range of 0.01 to 0.05. mu.m, in order to further improve the adhesion. The average particle diameter in the present invention is a volume average value measured by a dynamic light scattering method, wherein the silica particles (b2) are diluted with a well-dispersed solvent.

The undercoat composition (B) is used in the formation of the undercoat layer (B). The undercoat composition (b) contains the undercoat resin (b1), silica particles (b2), and optionally a crosslinking agent (b 3). The crosslinking agent (b3) is preferably a polycarboxylic acid. Examples of the polycarboxylic acid include trimellitic anhydride, pyromellitic anhydride, maleic anhydride, and succinic acid. One or more of these crosslinking agents (b3) may be used. Among these crosslinking agents (b3), trimellitic anhydride is preferable in terms of further improving adhesion.

Further, in the primer composition (B) for forming the primer layer (B), another resin (B4) may be blended as necessary as a component other than the components (B1) to (B3). Examples of the other resin (b4) include urethane resin, acrylic resin, blocked isocyanate resin, melamine resin, and phenol resin. One kind of these other resins (b4) may be used, or two or more kinds thereof may be used in combination.

In order to provide a viscosity that facilitates coating when the base coating composition (b) is coated on the support (a), an organic solvent is preferably blended in the base coating composition (b). Examples of the organic solvent include: toluene, ethyl acetate, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, isopropanol, diacetone alcohol, ethylene glycol, toluene, and the like. One or more of these solvents may be used in combination.

The amount of the organic solvent used is preferably appropriately adjusted according to a coating method used when coating on the support (a) and a desired film thickness of the undercoat layer (B), which will be described later.

In the undercoat composition (b), conventional additives such as a film-forming aid, a leveling agent, a thickener, a water-repellent agent, an antifoaming agent, and an antioxidant may be added as needed.

The undercoat layer (B) may be formed by applying the undercoat composition (B) on a part or the whole of the surface of the support (a) and removing the organic solvent contained in the undercoat composition (B).

Examples of the method for applying the undercoating composition (b) to the surface of the support (a) include gravure method, coating method, screen method, roll method, rotary method, spray method, capillary method, and the like.

As a method for removing the organic solvent contained in the coating layer after the undercoat composition (b) is applied to the surface of the support (a), for example, a method of drying using a dryer and volatilizing the organic solvent is generally used. The drying temperature may be set to a temperature within a range that allows the organic solvent to be volatilized and does not adversely affect the support (a) such as thermal deformation.

The thickness of the primer layer (B) formed using the primer composition (B) is preferably within a range in which the adhesion between the support (a) and the metal particle layer (C) described later is further improved, depending on the application in which the laminate of the present invention is used, and the thickness of the primer layer is preferably within a range from 10nm to 30 μm, more preferably within a range from 10nm to 1 μm, and still more preferably within a range from 10nm to 500 nm.

The surface of the undercoat layer (B) may be subjected to a surface treatment by a plasma discharge treatment such as a corona discharge treatment, a dry treatment such as an ultraviolet treatment, or a wet treatment using water, an acidic or alkaline chemical solution, an organic solvent, or the like, as necessary, so that the adhesiveness to the metal particle layer (C) can be further improved.

The metal particle layer (C) is formed on the undercoat layer (B), and examples of the metal constituting the metal particle layer (C) include transition metals and compounds thereof, and among them, ionic transition metals are preferable. Examples of the ionic transition metal include copper, silver, gold, nickel, palladium, platinum, and cobalt. Among these, silver is preferable because the metal plating layer (D) can be easily formed.

Examples of the metal constituting the metal plating layer (D) include copper, gold, silver, nickel, chromium, cobalt, and tin. Among these, copper is preferable for a laminate which has low electrical resistance and can be used for a corrosion-resistant printed wiring board.

As a method for producing the laminate of the present invention, there may be mentioned a method comprising first forming an undercoat layer (B) on a support (a), then applying a fluid containing metal particles (C), drying to remove an organic solvent or the like contained in the fluid, thereby forming a metal particle layer (C), and then forming the metal-plated layer (D) by electrolytic plating or electroless plating, or both.

The shape of the metal particles (C) used for forming the metal particle layer (C) is preferably a particle shape or a fiber shape. In addition, the size of the metal particles (c) is preferably nanometer size. Specifically, when the metal particles (c) are in the form of particles, the average particle diameter is preferably in the range of 1nm to 100nm, more preferably in the range of 1nm to 50nm, from the viewpoint of forming a fine conductive pattern and further reducing the resistance value. The average particle diameter means the same particle diameter as that described in the silica particles (b2), and "nanogram (Nanotrac) UPA-150" manufactured by macbeck (MicroTrac) can be used for the measurement.

On the other hand, when the metal particles (c) are in the form of fibers, the diameter of the fibers is preferably in the range of 5nm to 100nm or less, more preferably in the range of 5nm to 50nm or less, in order to form a fine conductive pattern and further reduce the resistance value. The length of the fiber is preferably in the range of 0.1 to 100 μm, more preferably in the range of 0.1 to 30 μm.

The content of the metal particles (c) in the fluid is preferably in the range of 1 to 90 mass%, more preferably in the range of 1 to 60 mass%, and still more preferably in the range of 1 to 10 mass%.

The component that can be blended in the fluid includes a dispersant or a solvent for dispersing the metal particles (c) in a solvent, and further includes a surfactant, a leveling agent, a viscosity adjuster, a film forming aid, an antifoaming agent, an antiseptic agent, and the like, which will be described later, as required.

In order to disperse the metal particles (c) in a solvent, a dispersant is preferably used. Examples of the dispersant include: dodecyl mercaptan, 1-octyl mercaptan, triphenylphosphine, dodecylamine, polyethylene glycol, polyvinylpyrrolidone, polyethyleneimine, polyvinylpyrrolidone; fatty acids such as myristic acid, caprylic acid, and stearic acid; and polycyclic hydrocarbon compounds having a carboxyl group such as cholic acid, glycyrrhizic acid, and abietic acid. Among these, the metal particle layer (C) is preferably a polymer dispersant in view of improving the adhesion between the metal particle layer (C) and a metal plating layer (D) described later by making the metal particle layer (C) porous, and examples of the polymer dispersant include: polyalkyleneimines such as polyethyleneimine and polypropyleneimine, compounds obtained by adding a polyoxyalkylene group to polyalkyleneimine, urethane resins, acrylic resins, and compounds containing a phosphoric acid group in the urethane resins or the acrylic resins.

As described above, by using a polymer dispersant as the dispersant, it is possible to remove the dispersant in the metal particle layer (C) and form a porous state, increase the size of the voids, and form voids having a size from the order of nanometers to the order of submicron microns as compared with a low-molecular dispersant.

The amount of the dispersant used to disperse the metal particles (c) is preferably in the range of 0.01 to 50 parts by mass, and more preferably in the range of 0.01 to 10 parts by mass, per 100 parts by mass of the metal particles (c).

In the case where the metal layer (C) is formed in a porous state by removing a dispersant by firing for the purpose of further improving the adhesion between the metal particle layer (C) and a metal plating layer (D) to be described later, the amount of the dispersant is preferably in a range of 0.1 to 10 parts by mass, and more preferably in a range of 0.1 to 5 parts by mass, based on 100 parts by mass of the metal particles (C).

As the solvent used in the fluid, an aqueous medium or an organic solvent may be used. Examples of the aqueous medium include distilled water, ion-exchanged water, pure water, and ultrapure water. Examples of the organic solvent include alcohol compounds, ether compounds, ester compounds, and ketone compounds.

Examples of the alcohol compound include: methanol, ethanol, n-propanol, isopropanol, n-butanol, isopropanol, sec-butanol, t-butanol, heptanol, hexanol, octanol, nonanol, decanol, undecanol, dodecanol, tridecanol, tetradecanol, pentadecanol, stearyl alcohol, allyl alcohol, cyclohexanol, terpineol, dihydroterpineol, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, diethylene glycol monoethyl ether, diethylene glycol monomethyl ether, diethylene glycol monobutyl ether, tetraethylene glycol monobutyl ether, propylene glycol monomethyl ether, dipropylene glycol monomethyl ether, tripropylene glycol monomethyl ether, propylene glycol monopropyl ether, dipropylene glycol monopropyl ether, tripropylene glycol monobutyl ether, and the like.

In addition to the metal particles (c) and the solvent, ethylene glycol, diethylene glycol, 1, 3-butanediol, isoprene glycol, and the like may be used as necessary in the fluid.

As the surfactant, general surfactants can be used, and examples thereof include: di-2-ethylhexyl sulfosuccinate, dodecylbenzene sulfonate, alkyl diphenyl ether disulfonate, alkyl naphthalene sulfonate, hexametaphosphate, and the like.

As the leveling agent, a general leveling agent can be used, and examples thereof include silicone compounds, acetylene glycol compounds, fluorine compounds, and the like.

As the viscosity modifier, a general thickener can be used, and examples thereof include: acrylic polymer or synthetic rubber latex which can be thickened by adjusting to alkalinity, urethane resin which can be thickened by molecular association, hydroxyethyl cellulose, carboxymethyl cellulose, methyl cellulose, polyvinyl alcohol, hydrogenated castor oil, amide wax, oxidized polyethylene, metal soap, dibenzylidene sorbitol and the like.

As the above-mentioned film-forming assistant, a general film-forming assistant can be used, and examples thereof include an anionic surfactant (e.g., dioctyl sulfosuccinate sodium salt), a hydrophobic nonionic surfactant (e.g., sorbitan monooleate), a polyether-modified siloxane, and silicone oil.

As the defoaming agent, a general defoaming agent can be used, and examples thereof include silicone defoaming agents, nonionic surfactants, polyethers, higher alcohols, and polymer surfactants.

As the preservative, a general preservative can be used, and examples thereof include an isothiazoline-based preservative, a triazine-based preservative, an imidazole-based preservative, a pyridine-based preservative, an azole-based preservative, and a pyrithione-based preservative.

The viscosity (measured at 25 ℃ using a B-type viscometer) of the fluid is preferably in the range of 0.1 to 500,000 mPas, more preferably in the range of 0.2 to 10,000 mPas. When the fluid is applied (printed) by an ink jet printing method, a relief reverse printing method, or the like, which will be described later, the viscosity thereof is preferably in the range of 5mPa · s to 20mPa · s.

Examples of a method for applying or printing the fluid on the undercoat layer (B) include an inkjet printing method, a reverse printing method, a screen printing method, an offset printing method, a gravure printing method, a flexographic printing method, a pad printing method, a spin coating method, a spray coating method, a bar coating method, a die coating method, a slit coating method, a roll coating method, a dip coating method, a spin coating method, a capillary coating method, and the like.

The mass per unit area of the metal particle layer (C) is preferably 1mg/m²～30,000mg/m²More preferably in the range of (1)]Is 1mg/m²～5,000mg/m²The range of (1). The thickness of the metal particle layer (C) can be adjusted by controlling the treatment time, current density, and the amount of the additive for plating used in the plating step in forming the metal plating layer (D).

The metal plating layer (D) constituting the laminate of the present invention is a layer provided for the purpose of forming a highly reliable wiring pattern capable of maintaining good electrical continuity without causing disconnection or the like for a long period of time, for example, when the laminate is used for a printed wiring board or the like.

The metal plating layer (D) is formed on the metal particle layer (C), and is preferably formed by plating. The plating treatment may be a wet plating method such as an electrolytic plating method or an electroless plating method, which can easily form the metal plating layer (D). In addition, two or more of these plating methods may be combined. For example, the metal plating layer (D) may be formed by performing electroless plating and then electrolytic plating.

The electroless plating method is, for example, the following method: by bringing the electroless plating solution into contact with the metal constituting the metal particle layer (C), a metal such as copper contained in the electroless plating solution is precipitated, thereby forming an electroless plating layer (coating) including a metal coating.

Examples of the electroless plating solution include an electroless plating solution containing a metal such as copper, silver, gold, nickel, chromium, cobalt, or tin, a reducing agent, and a solvent such as an aqueous medium or an organic solvent.

Examples of the reducing agent include dimethylaminoborane, hypophosphorous acid, sodium hypophosphite, dimethylaminoborane, hydrazine, formaldehyde, sodium borohydride, and phenol.

Further, as the electroless plating solution, those containing monocarboxylic acids such as acetic acid and formic acid; dicarboxylic acid compounds such as malonic acid, succinic acid, adipic acid, maleic acid, and fumaric acid; hydroxycarboxylic acid compounds such as malic acid, lactic acid, glycolic acid, gluconic acid, and citric acid; amino acid compounds such as glycine, alanine, iminodiacetic acid, arginine, aspartic acid, and glutamic acid; and organic acids such as aminopolycarboxylic acid compounds including iminodiacetic acid, nitrilotriacetic acid, ethylenediamine diacetic acid, ethylenediamine tetraacetic acid, diethylenetriamine pentaacetic acid, and the like, and soluble salts (sodium salts, potassium salts, ammonium salts, and the like) of these organic acids, and amine compounds such as ethylenediamine, diethylenetriamine, triethylenetetramine, and the like.

The electrolytic plating method is, for example, as follows: the electrolytic plating solution is electrified in a state of being in contact with the metal constituting the metal particle layer (C) or the surface of the electroless plating layer (coating film) formed by the electroless plating treatment, thereby depositing the metal such as copper contained in the electrolytic plating solution on the surface of the metal particles (C) constituting the metal particle layer (C) provided on the cathode or the electroless plating layer (coating film) formed by the electroless plating treatment, thereby forming the electrolytic plating layer (coating film).

Examples of the electrolytic plating solution include an electrolytic plating solution containing a sulfide of a metal such as copper, nickel, chromium, cobalt, or tin, sulfuric acid, and an aqueous medium. Specifically, an electrolytic plating solution containing copper sulfate, sulfuric acid, and an aqueous medium is exemplified.

The electroless plating solution and the electrolytic plating solution are preferably used in the range of 20 to 98 ℃.

As a method for forming the metal plating layer (D), a method in which electroless plating is performed and then electrolytic plating is performed is preferable in terms of easy control of the film thickness of the metal plating layer (D) to a desired film thickness from a thin film to a thick film.

The film thickness of the metal plating layer (D) is preferably 1 μm or more and 50 μm or less. The film thickness of the metal plating layer (D) can be adjusted by controlling the processing time, current density, and amount of plating additive used in the plating step in forming the metal plating layer (D).

Examples of the method for patterning the metal plating layer (D) include a photolithography etching method such as a subtractive method or a semi-additive method, and a method for plating a printed pattern of the metal particle layer (C).

The subtractive method is as follows: an etching resist layer having a shape corresponding to a desired pattern shape is formed on the metal plating layer (D) constituting the laminate of the present invention, which is manufactured in advance, and the metal plating layer (D) and the metal particle layer (C) from which the resist portion has been removed are dissolved and removed with a chemical solution by a subsequent development process, thereby forming a desired pattern. As the chemical solution, a chemical solution containing copper chloride, iron chloride, or the like can be used.

The semi-addition method comprises the following steps: the base coat layer (B) and the metal particle layer (C) are formed on the support (a), and after surface treatment is performed as necessary, a plating resist layer having a shape corresponding to a desired pattern is formed on the surface, and then the metal plating layer (D) is formed by an electroless plating method, an electrolytic plating method, or a combination thereof, and then the plating resist layer and the metal particle layer (C) in contact therewith are dissolved and removed in a chemical solution or the like, thereby forming a desired pattern.

The method of plating the printed pattern of the metal particle layer (C) is as follows: the pattern of the metal particle layer (C) is printed on the undercoat layer (B) formed on the support (a) by an ink jet method, an inverse printing method, or the like, and after surface treatment by plasma discharge treatment or the like as necessary, the metal plating layer (D) is formed on the surface of the formed metal particle layer (C) by an electroless plating method, an electrolytic plating method, or a combination thereof, thereby forming a desired pattern.

The laminate of the present invention obtained as described above can be suitably used as electronic components such as printed wiring boards, flexible printed wiring boards, conductive films for touch panels, metal meshes for touch panels, organic solar cells, organic EL elements, organic transistors, RFID such as noncontact IC cards, electromagnetic wave shields, LED lighting substrates, and digital signage by patterning the metal layer. In particular, it is most suitable for use in flexible printed wiring boards such as FCCL.

Examples

The present invention will be described in detail below with reference to examples. Furthermore, the present invention is not limited to the following examples.

Production example 1 production of undercoating resin (1)/Melamine resin

A reaction flask equipped with a reflux condenser, a thermometer, and a stirrer was charged with 600 parts by mass of formalin containing 37% by mass of formaldehyde and 7% by mass of methanol (formaldehyde content: 222 parts by mass (7.4mol), and methanol content: 42 parts by mass (1.31mol)) and 200 parts by mass of water and 350 parts by mass of methanol (10.92mol) were added thereto to obtain a uniform solution. Subsequently, a 25 mass% aqueous solution of sodium hydroxide was added to adjust the pH to 10, and then 310 parts by mass (2.46mol) of melamine was added thereto, and the solution was warmed to 85 ℃ to conduct a methylolation reaction (reaction time: 1 hour).

Subsequently, formic acid was added to adjust the pH to 7, and then the mixture was cooled to 60 ℃ to carry out etherification reaction. A25 mass% aqueous solution of sodium hydroxide was added at a clouding temperature of 40 ℃ to adjust the pH to 9, and the etherification reaction was stopped (reaction time: 1 hour). The remaining methanol was removed under reduced pressure at a temperature of 50 ℃ (methanol removal time: 4 hours). Thereafter, methyl ethyl ketone was added to obtain a melamine resin solution having a nonvolatile content of 2 mass%.

Production example 2 production of undercoating resin (2)/urethane-acrylic composite resin

In a nitrogen-substituted vessel including a thermometer, a nitrogen introduction tube, and a stirrer, 100 parts by mass of a polyester polyol (polyester polyol obtained by reacting 1, 4-cyclohexanedimethanol, neopentyl glycol, and adipic acid), 17.6 parts by mass of 2, 2-dimethylolpropionic acid, 21.7 parts by mass of 1, 4-cyclohexanedimethanol, and 106.2 parts by mass of dicyclohexylmethane diisocyanate were reacted with 178 parts by mass of methyl ethyl ketone, thereby obtaining an organic solvent solution of a urethane prepolymer having an isocyanate group at an end.

Next, 13.3 parts by mass of triethylamine was added to the organic solvent solution of the urethane resin, and a part or all of the carboxyl groups of the urethane resin was neutralized, and 380 parts by mass of water was further added thereto and sufficiently stirred, thereby obtaining an aqueous dispersion of the urethane resin.

Next, 8.8 parts by mass of a 25% by mass aqueous ethylenediamine solution was added to the aqueous dispersion, and the mixture was stirred to elongate the chains of the particulate polyurethane resin, followed by aging and solvent removal, thereby obtaining an aqueous dispersion of a urethane resin having a nonvolatile content of 30% by mass. The weight average molecular weight of the urethane resin was 53,000.

Then, 140 parts by mass of deionized water and 100 parts by mass of the aqueous dispersion of the urethane resin obtained above were placed in a reaction vessel equipped with a stirrer, a reflux condenser tube, a nitrogen introduction tube, a thermometer, a dropping funnel for dropping a monomer mixture and a dropping funnel for dropping a polymerization catalyst, and the temperature was raised to 80 ℃ while blowing nitrogen.

In a reaction vessel heated to 80 ℃, 20 parts by mass of a monomer mixture comprising 60 parts by mass of methyl methacrylate, 30 parts by mass of N-butyl acrylate and 10 parts by mass of N-butoxy methacrylamide, and an aqueous solution of ammonium persulfate (concentration: 0.5 mass%) were added dropwise from each dropping funnel while keeping the temperature in the reaction vessel at 80 ℃. + -. 2 ℃ for 120 minutes under stirring, and polymerization was carried out.

After the end of the dropping, stirring was performed at the same temperature for 60 minutes, thereby obtaining a urethane-acrylic composite resin including a shell layer of the urethane resin and a core layer of an acrylic resin.

Subsequently, the temperature in the reaction vessel was cooled to 40 ℃, deionized water was added so that the nonvolatile content became 2 mass%, and filtration was performed with a 200-mesh filter cloth, thereby obtaining an aqueous dispersion of a urethane-acrylic composite resin.

Production example 3 production of undercoat resin (3) A resin mixture of aminotriazine-modified novolak resin and epoxy resin

In a flask equipped with a thermometer, a cooling tube, a fractionating tube, and a stirrer, 750 parts by mass of phenol, 75 parts by mass of melamine, 346 parts by mass of 41.5 mass% formalin, and 1.5 parts by mass of triethylamine were charged, and the temperature was raised to 100 ℃ while paying attention to heat generation. After 2 hours of reaction at 100 ℃ under reflux, the reaction mixture was heated to 180 ℃ under normal pressure for 2 hours while removing water. Next, unreacted phenol was removed under reduced pressure to obtain an aminotriazine-modified novolak resin. The hydroxyl equivalent weight was 120 g/equivalent.

Subsequently, 65 parts by mass of an aminotriazine-modified novolak resin and 35 parts by mass of an epoxy resin ("EpICLON) 850-S", bisphenol A type epoxy resin, epoxy equivalent 188 g/equivalent, manufactured by Diegon (DIC) Co., Ltd.) were mixed, and then diluted with methyl ethyl ketone so that the nonvolatile content became 2% by mass, and the mixture was uniformly mixed to obtain a mixed resin solution of an aminotriazine-modified novolak resin and an epoxy resin.

Production example 4 production of undercoating resin (4)/blocked polyisocyanate

In a nitrogen-substituted reaction vessel equipped with a thermometer, a nitrogen gas inlet tube, and a stirrer, 6.3 parts by mass of 2, 2-dimethylolpropionic acid and 71.1 parts by mass of the uronate ester of 4,4' -diphenylmethane diisocyanate were reacted in methyl ethyl ketone to prepare an isocyanate compound, and then 17.8 parts by mass of phenol as a blocking agent was supplied to the reaction vessel and reacted to prepare a solvent solution of a blocked polyisocyanate.

Next, 4.8 parts by mass of triethylamine was added to the solvent solution of the blocked polyisocyanate to neutralize the carboxyl group of the blocked polyisocyanate. Thereafter, methyl ethyl ketone was added to obtain a blocked polyisocyanate solution containing 2 mass% of nonvolatile components.

Production example 5 production of silica particles (1) treated with silane coupling agent

A flask equipped with a thermometer, a cooling tube and a stirrer was charged with 500 parts by mass of a silica particle dispersion ("Snowtex) -OL" manufactured by Nissan chemical Co., Ltd.; average particle diameter 45nm and nonvolatile matter 20% by mass), and the temperature was raised to 50 ℃. Thereafter, 20 parts by mass of a silane coupling agent containing an epoxy group ("KBM-402", 3-glycidoxypropylmethyldimethoxysilane, nonvolatile matter: 100% by mass) was added. After confirming the exotherm, the mixture was stirred at 50 ℃ for 24 hours. Thereafter, the mixture was cooled to 30 ℃, diluted with isopropyl alcohol so that the nonvolatile content became 2 mass%, and uniformly mixed, thereby obtaining a dispersion of the silica particles (1).

Production example 6 production of silica particles (2) treated with silane coupling agent

A dispersion of silica particles (2) having a nonvolatile content of 2% by mass was obtained in the same manner as described above except that the silane coupling agent used in production example 5 was changed to an epoxy group-containing silane coupling agent ("KBM-303", 2- (3, 4-epoxycyclohexyl) ethyltrimethoxysilane, 100% by mass nonvolatile content, manufactured by shin-Etsu chemical Co., Ltd.).

Production example 7 production of silica particles (3) treated with silane coupling agent

A dispersion of silica particles (3) having a nonvolatile content of 2% by mass was obtained in the same manner as in preparation example 5, except that the silane coupling agent used in preparation example 5 was changed to a silane coupling agent containing an amino group ("KBM-573", N-phenyl-3-aminopropyltrimethoxysilane, nonvolatile content: 100% by mass ", manufactured by shin-Etsu chemical industries, Ltd.).

Production example 8 production of silica particles (4) treated with silane coupling agent

A dispersion of silica particles (4) having a nonvolatile content of 2% by mass was obtained in the same manner as described above except that the silane coupling agent used in production example 5 was changed to a methacrylic group-containing silane coupling agent ("KBE-502", 3-methacryloxypropylmethyldiethoxysilane, nonvolatile content: 100% by mass ", manufactured by shin-Etsu chemical Co., Ltd.).

Preparation example 1 preparation of undercoating composition (1)

To 100 parts by mass of the melamine resin solution having a nonvolatile content of 2% by mass obtained in production example 1, 1 part by mass of the dispersion of silica particles (1) obtained in production example 5 was added and mixed for 30 minutes to obtain an undercoating composition (1).

Preparation example 2 preparation of undercoating composition (2)

To 100 parts by mass of the aqueous dispersion of a urethane-acrylic composite resin having 2% by mass of nonvolatile components obtained in production example 2, 5 parts by mass of the dispersion of silica particles (1) obtained in production example 5 was added and mixed for 30 minutes to obtain an undercoating composition (2).

Preparation example 3 preparation of undercoating composition (3)

To 100 parts by mass of the mixture solution of the aminotriazine-modified novolak having 2% by mass of nonvolatile components and the epoxy resin obtained in production example 3, 10 parts by mass of the dispersion liquid of the silica particles (1) obtained in production example 5 was added and mixed for 30 minutes to obtain an undercoating composition (3).

Preparation example 4 preparation of undercoating composition (4)

To 100 parts by mass of a mixed resin solution of an aminotriazine-modified novolak resin having a nonvolatile component of 2% by mass and an epoxy resin obtained in production example 3, 25 parts by mass of the dispersion of silica particles (2) obtained in production example 6 was added and mixed for 30 minutes to obtain an undercoating composition (4).

Preparation example 5 preparation of undercoating composition (5)

To 100 parts by mass of a mixed resin solution of an aminotriazine-modified novolak resin and an epoxy resin having a nonvolatile content of 2% by mass obtained in production example 3, 75 parts by mass of the dispersion of silica particles (2) obtained in production example 6 was added and mixed for 30 minutes to obtain an undercoating composition (5).

Preparation example 6 preparation of undercoating composition (6)

To 100 parts by mass of the blocked polyisocyanate solution having a nonvolatile content of 2% by mass obtained in production example 4, 150 parts by mass of the dispersion of silica particles (3) obtained in production example 7 was added and mixed for 30 minutes to obtain an undercoating composition (6).

Preparation example 7 preparation of undercoating composition (7)

To 100 parts by mass of the melamine resin solution having a nonvolatile content of 2% by mass obtained in production example 1, 400 parts by mass of the dispersion of silica particles (4) obtained in production example 8 was added and mixed for 30 minutes to obtain an undercoating composition (7).

Preparation example 8 preparation of undercoating composition (R1)

A mixed resin solution of the aminotriazine-modified novolak resin and the epoxy resin having a nonvolatile content of 2 mass% obtained in production example 3 was used as the undercoat composition without adding a silica particle dispersion (R1).

Preparation example 9 preparation of undercoating composition (R2)

Silica particle dispersion ("Snowtex) -OL" manufactured by Nissan chemical Co., Ltd.; average particle diameter 45nm and nonvolatile matter 20% by mass) was diluted with isopropyl alcohol so that nonvolatile matter became 2% by mass, and 75 parts by mass of silica particles which were not treated with a silane coupling agent were prepared. The silica particles were added to 100 parts by mass of a mixed resin solution of an aminotriazine-modified novolak resin having a nonvolatile component of 2% by mass and an epoxy resin obtained in production example 3, and mixed for 30 minutes to obtain an undercoat composition (R2).

Preparation example 10 preparation of fluid (1)

According to example 1 described in japanese patent No. 4573138, a cationic silver nanoparticle including a flaky block having a grayish green metallic luster was obtained as a composite of a silver nanoparticle and an organic compound having a cationic group (amino group). Thereafter, the silver nanoparticle powder was dispersed in a mixed solvent of 45 parts by mass of ethylene glycol and 55 parts by mass of ion-exchanged water, to prepare a fluid (1) containing 5% by mass of cationic silver nanoparticles.

(example 1)

The undercoat composition (1) obtained in preparation example 1 was applied to the surface of a polyimide film ("Capton (Capton)50 EN-C"; thickness 12.5 μm) manufactured by Toronto (TORAY DU PONT) Co., Ltd.) in such a manner that the dried thickness thereof was 100nm using a desktop mini-coater ("Printing Proofer") manufactured by RK Print coating apparatus (RK Print Coat Instrument Co., Ltd.). Subsequently, the polyimide film was dried at 150 ℃ for 5 minutes by using a hot air dryer, thereby forming an undercoat layer on the surface of the polyimide film.

The fluid (1) obtained above was applied to the surface of the formed primer layer using a bar coater. Subsequently, the metal particle layer (C) was dried at 200 ℃ for 5 minutes to form a silver layer (film thickness: 100nm) corresponding to the metal particle layer (C).

The silver layer obtained above was set on the cathode side, phosphorus-containing copper was set on the anode side, and an electrolytic plating solution containing copper sulfate was used at a current density of 2.5A/dm²Electrolytic plating was performed for 30 minutes, whereby a copper plated layer (film thickness 15 μm) by electrolytic copper plating was formed on the surface of the copper plated layer by electroless copper plating. As the electrolytic plating solution, 70g/L copper sulfate, 200g/L sulfuric acid, 50mg/L chloride ion, and 5ml/L additive ("TOP Lucina) SF-M" manufactured by Orye pharmaceutical industry (Japan) were used. Further, a combination of a copper plating layer based on electroless copper plating and a copper plating layer based on electrolytic copper plating formed thereon corresponds to the metal plating layer (D).

By the above method, a laminate (1) in which the support (a), the undercoat layer (B), the metal particle layer (C), and the metal plating layer (D) are sequentially laminated is obtained.

(examples 2 to 7, comparative examples 1 and 2)

Laminates (2) to (7), laminate (R1), and laminate (R2) were obtained in the same manner as in example 1, except that the undercoating composition (1) used in example 1 was changed to the undercoating compositions (2) to (7), the undercoating composition (R1), or the undercoating composition (R2).

The following measurements and evaluations were made with respect to the laminates (1) to (7), the laminate (R1), and the laminate (R2) obtained in examples 1 to 7 and comparative examples 1 to 2.

[ measurement of peeling Strength before heating ]

The obtained laminates were measured for peel strength using "Autguarv AGS-X500N" manufactured by Shimadzu corporation. The lead used for the measurement was set to have a width of 5mm and a peel angle of 90 °. The peel strength tends to be higher as the thickness of the metal plating layer is thicker, and the peel strength in the present invention is measured based on the measurement value of the metal plating layer at a thickness of 15 μm.

[ evaluation of adhesion ]

The adhesion was evaluated based on the measured peel strength before heating according to the following criteria.

A: the peel strength is 650N/m or more.

B: the peel strength is 450N/m or more and less than 650N/m.

C: the peel strength is 250N/m or more and less than 450N/m.

D: the peel strength value is less than 250N/m.

[ measurement of peeling Strength after heating ]

The obtained laminates were stored in a drier set at 150 ℃ for 300 hours and heated. After heating, the peel strength was measured by the same method as described above.

[ evaluation of Heat resistance ]

Using the peel strength values before and after heating measured as described above, the retention rate before and after heating was calculated, and the heat resistance was evaluated according to the following criteria.

A: the retention rate is 85% or more.

B: the retention rate is 70% or more and less than 85%.

C: the retention rate is 55% or more and less than 70%.

D: the retention was less than 55%.

The compositions of the undercoating compositions used in examples 1 to 7 and comparative examples 1 and 2, the results of measuring the peel strength before and after heating, and the results of evaluating the adhesion and heat resistance are shown in table 1. The composition of the undercoating composition represents only nonvolatile components.

[ Table 1]

It was confirmed that the laminates (1) to (7) obtained in examples 1 to 7 as the laminate of the present invention had high initial (before heating) peel strength and excellent adhesion. Further, the peel strength after the heat resistance test at 150 ℃ for 300 hours was also reduced very little, and the heat-resistant adhesion was also excellent.

On the other hand, the laminate (R1) obtained in comparative example 1 was an example using an undercoat layer containing no silica particles, and it was confirmed that the peel strength in the initial stage (before heating) was relatively high, but the peel strength after the heat resistance test at 150 ℃ for 300 hours was greatly reduced, and the heat-resistant adhesion was poor.

In addition, the laminate (R2) obtained in comparative example 2 was an example using an undercoat layer containing silica particles that were not treated with a silane coupling agent, and the peel strength in the initial stage (before heating) was low, and the retention of the peel strength after the heat resistance test at 150 ℃ for 300 hours was high.

Claims (9)

1. A laminate comprising a support (A) and, laminated thereon in this order, a primer layer (B) and a metal particle layer (C), wherein the primer layer (B) comprises a primer resin (B1) and silica particles (B2) treated with a silane coupling agent.

2. The laminate according to claim 1, wherein the content of the silica particles (B2) in the undercoat layer (B) is in the range of 1 to 400 parts by mass relative to 100 parts by mass of the undercoat resin (B1).

3. The laminate according to claim 1 or 2, wherein the average particle diameter of the silica particles (b2) is 0.001 to 0.5 μm.

4. The laminate according to any one of claims 1 to 3, wherein a metal plating layer (D) is further laminated on the metal particle layer (C).

5. The laminate of any one of claims 1 to 4, wherein the basecoat resin (b1) comprises an aminotriazine-modified novolak resin.

6. A printed wiring board characterized by having the laminate according to any one of claims 1 to 5.

7. A flexible printed wiring board characterized by having the laminate according to any one of claims 1 to 5 in which the support (A) is a film.

8. An electromagnetic wave shield comprising the laminate according to any one of claims 1 to 5.

9. A molded article comprising the laminate according to any one of claims 1 to 5.