KR20230136055A - Method for manufacturing printed wiring board - Google Patents

Abstract

[Problem] To provide a method for manufacturing a printed wiring board that can manufacture a printed wiring board while suppressing peeling defects between the insulating layer and the support.
[Solution] (I) A process of laminating a resin sheet including a support provided with a release layer and a resin composition layer formed on the release layer of the support on the inner layer substrate so that the resin composition layer is bonded to the inner layer substrate, ( A method for manufacturing a printed wiring board comprising the steps of (II) heat curing the resin composition layer in a nitrogen atmosphere, and (III) peeling off the support in this order; The release layer contains a (meth)acrylic resin; The resin composition layer contains a resin composition containing an imidazole-based compound; Production of a printed wiring board, wherein the thermal curing of the resin composition layer includes performing a heat treatment to maintain the resin composition layer at a temperature T1 and performing a heat treatment to maintain the resin composition layer at a temperature T2 higher than the temperature T1 in this order. method.
[Representative] None

Description

Manufacturing method of printed wiring board {METHOD FOR MANUFACTURING PRINTED WIRING BOARD}

The present invention relates to a method of manufacturing a printed wiring board.

Printed wiring boards are widely used in various electronic devices. Printed wiring boards are required to have finer circuit wiring and higher density in order to miniaturize and increase functionality of electronic devices. Here, as a manufacturing method for a printed wiring board, a manufacturing method using a build-up method in which insulating layers and conductor layers are alternately stacked on an inner layer substrate is known. The insulating layer is formed, for example, by forming a resin composition layer containing a resin composition on an inner layer substrate and thermosetting the resin composition layer (Patent Documents 1 and 2).

Japanese Patent Publication No. 2002-167427 Japanese Patent Publication No. 2013-75948

One of the methods for forming the insulating layer of a printed wiring board is a method using a resin sheet. In this method, a resin sheet including a support and a resin composition layer is prepared, the inner layer substrate and the resin composition layer are laminated, and the resin composition layer is heat-cured to obtain an insulating layer. In this method, thermal curing of the resin composition layer may be performed while the resin composition layer and the support are in contact, and the support may be peeled off after the thermal curing. For example, in order to prevent damage to the insulating layer when forming a via hole by irradiation of a laser light, the resin composition layer is heat-cured to form an insulating layer, and after forming the via hole in the insulating layer, the support is peeled off. There are cases.

Additionally, thermal curing of the resin composition layer may be performed under a nitrogen atmosphere. For example, when thermal curing of the resin composition layer is performed in an air atmosphere, components included in the resin composition layer may deteriorate due to oxidation. In contrast, when thermal curing of the resin composition layer is performed in a nitrogen atmosphere, deterioration due to oxidation can be suppressed, and thus an insulating layer with excellent dielectric and mechanical properties can be formed.

However, when the resin composition layer is heat-cured in a nitrogen atmosphere without peeling off the support, peeling defects sometimes occur between the support and the insulating layer obtained by curing the resin composition layer. As a result of examination by the present inventor, it was found that the above peeling defect occurs when the resin composition layer contains an imidazole-based compound and the support body is provided with a release layer containing a (meth)acrylic resin.

The present invention was created in view of the above problems, and its purpose is to provide a method for manufacturing a printed wiring board that can manufacture a printed wiring board while suppressing peeling defects between the insulating layer and the support.

The present inventor has diligently studied to solve the above problems. As a result, the present inventor discovered that the above-described problem can be solved when thermal curing of the resin composition layer includes curing the resin composition layer in stages by changing the curing temperature, and completed the present invention.

That is, the present invention includes the following.

[1] (I) A process of laminating a resin sheet including a support provided with a release layer and a resin composition layer formed on the release layer of the support to the inner layer substrate so that the resin composition layer is bonded to the inner layer substrate,

(II) a process of thermosetting the resin composition layer in a nitrogen atmosphere, and

(III) Process of peeling off the support

A method of manufacturing a printed wiring board comprising in this order;

The release layer contains a (meth)acrylic resin;

The resin composition layer contains a resin composition containing an imidazole-based compound;

Production of a printed wiring board, wherein the thermal curing of the resin composition layer includes performing a heat treatment to maintain the resin composition layer at a temperature T1 and performing a heat treatment to maintain the resin composition layer at a temperature T2 higher than the temperature T1 in this order. method.

[2] The method for producing a printed wiring board according to [1], wherein the resin composition contains a thermosetting resin.

[3] The thermosetting resin is at least one selected from the group consisting of epoxy resin, phenol resin, activated ester resin, carbodiimide resin, acid anhydride resin, amine resin, benzoxazine resin, cyanate ester resin, and thiol resin. The manufacturing method of the printed wiring board described in [2], including.

[4] The method for manufacturing a printed wiring board according to any one of [1] to [3], wherein the temperature T2 is 150°C or higher.

[5] The method for manufacturing a printed wiring board according to any one of [1] to [4], wherein the difference T2-T1 between the temperature T1 and the temperature T2 is 20°C or more.

[6] The method for manufacturing a printed wiring board according to any one of [1] to [5], wherein the temperature T1 is 50°C or higher.

[7] The print according to any one of [1] to [6], wherein the step (II) includes raising the temperature of the resin composition layer to the temperature T2 at a temperature increase rate of 0.5 ° C./min or more and 30 ° C./min or less. Manufacturing method of wiring board.

According to the present invention, a printed wiring board can be manufactured while suppressing peeling defects between the insulating layer and the support.

Hereinafter, the present invention will be described by showing embodiments and examples. However, the present invention is not limited to the embodiments and examples shown below, and may be implemented with arbitrary changes without departing from the scope of the claims and the above equivalents.

In the following description, unless otherwise specified, “long” refers to the shape of a film or sheet having a length of 10 times or more relative to the width. The length is preferably 20 times or more than the width, and specifically, it may be a length long enough to be wound into a roll and stored or transported. There is no particular upper limit to the length, and for example, it may be 100,000 times or less than the width.

[Overview of printed wiring board manufacturing method]

The method for manufacturing a printed wiring board according to one embodiment of the present invention manufactures a printed wiring board using a support provided with a release layer and a resin sheet provided with a resin composition layer formed on the release layer of the support. Specifically, the manufacturing method of the printed wiring board according to this embodiment is

(I) A process of laminating a resin sheet on an inner layer substrate so that the resin composition layer is bonded to the inner layer substrate,

(II) a process of thermosetting the resin composition layer in a nitrogen atmosphere, and

(III) Process of peeling off the support

Included in this order: In this method, an insulating layer is formed by curing the resin composition layer, so a printed wiring board provided with the insulating layer can be manufactured.

The release layer provided by the support contains (meth)acrylic resin. Additionally, the resin composition layer contains a resin composition containing an imidazole-based compound. In addition, the heat curing of the resin composition layer in step (II) involves performing a heat treatment to maintain the resin composition layer at a temperature T1, and then performing a heat treatment to maintain the resin composition layer at a temperature T2 higher than the temperature T1. It includes

Conventionally, when a release layer containing a (meth)acrylic resin and a resin composition containing an imidazole-based compound are combined and heat treatment is further performed in a nitrogen atmosphere, peeling defects occur between the insulating layer and the support. Specifically, when attempting to peel off the support, adhesion may occur between the insulating layer and the support, and the insulating layer or the support may be damaged. On the other hand, when the conditions of heat curing in step (II) are controlled as in the present embodiment, peeling defects between the insulating layer and the support can be suppressed.

The present inventor speculates a structure that can suppress peeling defects as described above as follows. However, the technical scope of the present invention is not limited to the structure described below.

When thermal curing of the resin composition layer is performed in air, the catalytic activity of the imidazole-based compound is suppressed by oxygen and carbon dioxide contained in the air. However, when thermal curing is performed in a nitrogen atmosphere, the catalytic activity of the imidazole-based compound is not suppressed. Therefore, conventionally, due to the catalytic activity of the imidazole-based compound, a reaction occurs between the (meth)acrylic resin contained in the release layer and one or more components contained in the resin composition, and as a result, the release layer and the resin There may be cases where the composition layer sticks. Through examination by the present inventor, it is inferred that the (meth)acrylic resin in the release layer reacts with the thermosetting resin that may be contained in the resin composition, and that it reacts significantly with epoxy resin, phenol resin, and active ester resin among them. The present inventor speculates that this adhesion is one of the causes of conventional peeling defects.

In contrast, in the method for manufacturing a printed wiring board according to the present embodiment, a stepwise temperature increase including maintaining at a temperature T1 and maintaining at a temperature T2 higher than the temperature T1 is performed to cure the resin composition layer in stages. . In such stepwise curing, the reaction between the components contained in the resin composition layer proceeds prior to the reaction between the (meth)acrylic resin contained in the release layer and the components contained in the resin composition. For example, as a result of the reaction between components contained in the resin composition layer at temperature T1, the number of reactive components in the resin composition layer decreases. Therefore, at temperature T2, the progress of the reaction between the (meth)acrylic resin contained in the release layer and the component contained in the resin composition layer becomes small. Therefore, adhesion between the release layer and the resin composition layer can be suppressed, and peeling defects can be suppressed.

[Resin sheet]

The resin sheet used in the method for manufacturing a printed wiring board according to one embodiment of the present invention includes a support provided with a release layer, and a resin composition layer provided on the release layer of the support.

-Support-

The support body is usually provided with a support base material, and a release layer is provided on this support base material. Examples of the supporting base material include thermoplastic resin films, metal foils, and release papers, with thermoplastic resin films and metal foils being preferred.

When using a thermoplastic resin film as a support substrate, examples of the thermoplastic resin include polyesters such as polyethylene terephthalate (PET) and polyethylene naphthalate (PEN), polycarbonate (PC), and polymethyl methacrylate (PMMA). ), acrylic, cyclic polyolefin, triacetyl cellulose (TAC), polyether sulfide (PES), polyether ketone, polyimide, etc. Among them, polyethylene terephthalate and polyethylene naphthalate are preferable, and inexpensive polyethylene terephthalate is especially preferable.

When using a metal foil as a support base material, examples of the metal foil include copper foil, aluminum foil, etc., and copper foil is preferable. As the copper foil, a foil made of the simple metal of copper may be used, or a foil made of an alloy of copper and other metals (e.g., tin, chromium, silver, magnesium, nickel, zirconium, silicon, titanium, etc.) may be used. .

The support substrate may be subjected to surface treatment such as mat treatment, corona treatment, or antistatic treatment on the surface on the release layer side.

The thickness of the support base material is not particularly limited, but is preferably in the range of 5 μm to 75 μm, and more preferably in the range of 10 μm to 60 μm.

The release layer contains (meth)acrylic resin. In this specification, “(meth)acrylic resin” includes (meth)acrylic compounds and polymers thereof. Additionally, the “(meth)acrylic compound” includes an acrylic compound containing an acryloyl group, a methacryloyl compound containing a methacryloyl group, and combinations thereof.

Generally, the release layer is formed using a release agent. The release agent usually contains a release compound as a compound capable of imparting release property, and may further contain any resin other than the release compound as needed. Accordingly, the release layer formed using the release agent includes, in one example, a release compound, and may further include an optional resin as needed. In another example, the release layer formed using a release agent may be formed by combining some or all of the components contained in the release agent through reactions such as polymerization reaction and crosslinking reaction and curing the release agent. Therefore, in this example, the release layer may include a release compound and any resin contained in the release agent, and their reaction products (for example, polymers). The (meth)acrylic resin may be contained as a release compound, may be contained as an arbitrary resin, or may be contained as an organism producing these reactions.

A release compound refers to a compound that can exert the function of lowering the surface free energy of the release layer or lowering the coefficient of static friction of the release layer. Therefore, the (meth)acrylic resin as a release compound may be a (meth)acrylic resin that can exert the above functions.

Examples of the (meth)acrylic resin as a release compound include (meth)acrylic resin containing a long-chain alkyl group, (meth)acrylic resin containing a fluorine atom, etc.

A long-chain alkyl group usually refers to an alkyl group having 12 or more carbon atoms, and preferably 16 or more carbon atoms. Since the (meth)acrylic resin containing such a long carbon chain in its molecule has high hydrophobicity, it can exhibit high release properties. The upper limit of the number of carbon atoms of the long-chain alkyl group may be, for example, 25 or less. Examples of the (meth)acrylic resin containing a long-chain alkyl group include long-chain acrylates such as tetradecyl acrylate and octadecyl acrylate; long-chain acrylic methacrylates such as tetradecyl methacrylate and octadecyl methacrylate; and polymers thereof.

Examples of the (meth)acrylic resin containing a fluorine atom include fluoroalkyl acrylates such as trifluoroethyl acrylate; Fluoroaryl acrylates such as pentafluorophenyl acrylate; Fluoroalkyl methacrylates such as trifluoroethyl methacrylate; Fluoroaryl methacrylates such as pentafluorophenyl methacrylate; and polymers thereof.

Examples of (meth)acrylic resins as arbitrary resins include acrylic acid, methyl acrylate, ethyl acrylate, isopropyl acrylate, n-butyl acrylate, isobutyl acrylate, n-hexyl acrylate, lauryl acrylate, and 2-ethylhexyl acrylate. , acrylic compounds such as 2-hydroxyethyl acrylate, hydroxypropyl acrylate, acrylamide, N-methylol acrylamide, and diacetone acrylamide; Methacrylic acid, methyl methacrylate, ethyl methacrylate, isopropyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, n-hexyl methacrylate, lauryl methacrylate, 2-methacrylic acid. Methacrylic compounds such as hydroxyethyl and hydroxypropyl methacrylate; and polymers thereof.

One type of (meth)acrylic resin may be used alone, or two or more types may be used in combination.

The amount of (meth)acrylic resin in the release layer is preferably 30% by mass or more, more preferably 50% by mass or more, further preferably 70% by mass or more, particularly preferably 90% by mass or more, based on 100% by mass of the release layer. It is more than mass %, and is usually 100 mass % or less. Conventionally, when a release layer containing a (meth)acrylic resin was adopted, a problem of poor peeling between the insulating layer and the support occurred. By the manufacturing method described in this embodiment, peeling defects as this problem can be suppressed.

In addition, the amount of (meth)acrylic resin in the release agent used for producing the release layer is preferably 30% by mass or more, more preferably 50% by mass or more, based on 100% by mass of the non-volatile component of the release agent. Typically, it is 70% by mass or more, particularly preferably 90% by mass or more, and is usually 100% by mass or less. Conventionally, when employing a release layer formed using a release agent containing a (meth)acrylic resin, the problem of poor peeling between the insulating layer and the support occurred. By the manufacturing method described in this embodiment, peeling defects as this problem can be suppressed.

The release layer may further contain arbitrary components other than the (meth)acrylic resin in combination with the (meth)acrylic resin. In addition, the release agent for forming the release layer may further contain arbitrary components other than the (meth)acrylic resin in combination with the (meth)acrylic resin. As arbitrary components other than (meth)acrylic resin, release compounds other than (meth)acrylic resin can be mentioned, for example. Examples of release compounds other than (meth)acrylic resins include long-chain alkyl group-containing resins, olefin resins, fluorine compounds, and wax-based compounds.

Examples of long-chain alkyl group-containing compounds include compounds other than (meth)acrylic resins containing long-chain alkyl groups. Specific examples of long-chain alkyl group-containing compounds include the "Ashioresin" (registered trademark) series, a long-chain alkyl compound manufactured by Ashio Sangyo Co., Ltd., the "Pyroyl" (registered trademark) series, a long-chain alkyl compound manufactured by Lion Specialty Chemicals, and Chukyo Yushi Co., Ltd. and the “ReGem” series, which are aqueous dispersions of manufactured long-chain alkyl compounds.

Examples of olefin resins include propylene, 1-butene, 1-pentene, 1-hexene, 4-methyl-1-pentene, 1-heptene, 1-octene, 1-nonene, 1-decene, and 1-undecene. , 1-dodecene, etc.

Examples of the fluorine compound include compounds other than (meth)acrylic resin containing a fluorine atom in the molecule. Specific examples of fluorine compounds include perfluoroalkyl group-containing compounds, polymers of olefin compounds containing fluorine atoms, and aromatic fluorine compounds such as fluorobenzene.

Examples of wax-based compounds include natural wax, synthetic wax, and a combination of these waxes. Natural waxes include plant-based waxes, animal-based waxes, mineral-based waxes, and petroleum waxes. Examples of plant-based waxes include candelilla wax, carnauba wax, rice wax, wood wax, and jojoba oil. Examples of animal waxes include beeswax, lanolin, and spermaceti. Examples of mineral waxes include montan wax, ozokerite, and ceresin. Examples of petroleum wax include paraffin wax, microcrystalline wax, and petrolatum. Examples of synthetic waxes include synthetic hydrocarbons, denatured waxes, hydrogenated waxes, fatty acids, acid amides, amines, imides, esters, and ketones. Examples of synthetic hydrocarbons include Fischer Tropsch wax (also known as Sasol wax) and polyethylene wax. In addition, synthetic hydrocarbons include polymers selected from the group consisting of polypropylene, ethylene-acrylic acid copolymer, polyethylene glycol, polypropylene glycol, block conjugates of polyethylene glycol and polypropylene glycol, and graft conjugates of polyethylene glycol and polypropylene glycol. Among them, those of low molecular weight (specifically, viscosity average molecular weight of 500 or more and 20,000 or less) may be included. Examples of modified wax include montan wax derivatives, paraffin wax derivatives, and microcrystalline wax derivatives. Here, the derivative refers to a compound obtained by any of purification, oxidation, esterification, saponification, or a combination thereof. Examples of hydrogenated wax include hydrogenated castor oil and hydrogenated castor oil derivatives.

Arbitrary release compounds other than (meth)acrylic resin may be used individually or in combination of two or more types.

The amount of the release compound (the total of the (meth)acrylic resin as the release compound and the release compounds other than the (meth)acrylic resin) in the release agent is preferably 10% by mass or more, based on 100% by mass of the non-volatile component of the release agent. Preferably it is 15 mass% or more, especially preferably 20 mass% or more, preferably 90 mass% or less, more preferably 60 mass% or less, and particularly preferably 40 mass% or less.

In addition, the amount of the release compound (the total of the (meth)acrylic resin as the release compound and the release compounds other than the (meth)acrylic resin) in the release layer is preferably 10% by mass or more, based on 100% by mass of the release layer. Preferably it is 15 mass% or more, especially preferably 20 mass% or more, preferably 90 mass% or less, more preferably 60 mass% or less, and particularly preferably 40 mass% or less.

Other examples of optional components include arbitrary resins other than (meth)acrylic resin. Arbitrary resins other than (meth)acrylic resins include epoxy resins, melamine resins, oxazoline compounds, carbodiimide compounds, polyester resins, and urethane resins. Arbitrary resins other than (meth)acrylic resin may be used individually or in combination of two or more types.

The amount of any resin (the total of (meth)acrylic resin as an optional resin and any resin other than (meth)acrylic resin) in the mold release agent is preferably 10% by mass based on 100% by mass of the non-volatile component of the mold release agent. or more, more preferably 20 mass% or more, particularly preferably 40 mass% or more, preferably 90 mass% or less, more preferably 80 mass% or less, especially preferably 60 mass% or less.

In addition, the amount of any resin (the total of (meth)acrylic resin as an optional resin and any resin other than (meth)acrylic resin) in the release layer is preferably 10% by mass with respect to 100% by mass of the release layer. or more, more preferably 20 mass% or more, particularly preferably 40 mass% or more, preferably 90 mass% or less, more preferably 80 mass% or less, especially preferably 60 mass% or less.

Other examples of optional components include additives such as lubricants, inorganic particles, organic particles, surfactants, antioxidants, and thermal initiators. These additives may be used individually or in combination of two or more types. The amount of the additive is not particularly limited, but may be, for example, 0.01% by mass or more and 10% by mass or less with respect to a total of 100% by mass of the release compound and any resin.

The thickness of the release layer is preferably 50 nm or more, more preferably 70 nm or more, preferably 400 nm or less, more preferably 200 nm or less, and particularly preferably 130 nm or less.

The support can be produced, for example, by a method comprising applying a release agent to the surface of the support substrate. The mold release agent may further contain a solvent in combination with a non-volatile component such as the (meth)acrylic resin and optional components described above. When the release agent contains a solvent, the method for producing the support preferably includes drying after applying the release agent.

As the solvent, an aqueous solvent is preferable from the viewpoint of suppressing rapid evaporation of the solvent and forming a uniform release layer. Examples of aqueous solvents include water; Mixed solvents of water and organic solvents soluble in water, such as alcohol solvents, ketone solvents, and glycol solvents, are included. One type of solvent may be used individually, or two or more types may be used in combination. When using a solvent, the nonvolatile component concentration of the mold release agent is preferably 40% by mass or less from the viewpoint of improving applicability and forming a uniform mold release layer.

Examples of the application method of the release agent include the wire bar coat method, reverse coat method, gravure coat method, die coat method, blade coat method, dip coat method, air knife coat method, curtain coat method, and roller coat method. You can.

The drying temperature of the mold release agent is not particularly limited. In one example, drying may be performed in a temperature range of 80°C or higher and 130°C or lower. Additionally, in another example, drying may be performed at a temperature range of 160°C or higher and 240°C or lower.

A layer containing the non-volatile component of the mold release agent can be formed by applying the mold release agent to the surface of the support substrate and drying it as necessary. This layer may be used as a release layer. Additionally, a mold release layer may be obtained by subjecting the layer containing the non-volatile component of the mold release agent to a curing treatment. Examples of hardening treatment include heat treatment and ultraviolet irradiation treatment. Usually, through the curing treatment, reactions such as polymerization reaction and crosslinking reaction of some or all of the components contained in the release agent proceed, and the release agent can be cured, so that a release layer made of a cured product of the release agent can be obtained.

In addition, the method for producing the support may include arbitrary treatments such as stretching treatment, if necessary.

-Resin composition layer-

The resin sheet has a resin composition layer formed on a release layer of a support. Usually, the resin composition layer is in contact with the release layer of the support, and no other layers are provided between the release layer and the resin composition layer. This resin composition layer contains a resin composition, and preferably contains only a resin composition.

The resin composition contains (A) an imidazole-based compound. (A) Imidazole-based compounds usually function as a curing catalyst in a resin composition. Specifically, the resin composition usually contains a thermosetting resin (B), and the imidazole-based compound (A) can function as a catalyst to promote the curing reaction of the thermosetting resin (B).

(A) Imidazole-based compounds include, for example, 2-methylimidazole, 2-undecylimidazole, 2-heptadecylimidazole, 1,2-dimethylimidazole, and 2-ethyl-4. -Methylimidazole, 1,2-dimethylimidazole, 2-ethyl-4-methylimidazole, 2-phenylimidazole, 2-phenyl-4-methylimidazole, 1-benzyl-2- Methylimidazole, 1-benzyl-2-phenylimidazole, 1-cyanoethyl-2-methylimidazole, 1-cyanoethyl-2-undecylimidazole, 1-cyanoethyl-2 -Ethyl-4-methylimidazole, 1-cyanoethyl-2-phenylimidazole, 1-cyanoethyl-2-undecylimidazolium trimellitate, 1-cyanoethyl-2-phenyl Midazolium trimellitate, 2,4-diamino-6-[2'-methylimidazolyl-(1')]-ethyl-s-triazine, 2,4-diamino-6-[2'- Undecylimidazolyl-(1')]-ethyl-s-triazine, 2,4-diamino-6-[2'-ethyl-4'-methylimidazolyl-(1')]-ethyl- s-triazine, 2,4-diamino-6-[2'-methylimidazolyl-(1')]-ethyl-s-triazineisocyanuric acid adduct, 2-phenylimidazolisocyanuric acid Acid adduct, 2-phenyl-4,5-dihydroxymethylimidazole, 2-phenyl-4-methyl-5-hydroxymethylimidazole, 2,3-dihydro-1H-pyrrolo[1 ,2-a] imidazole compounds such as benzimidazole, 1-dodecyl-2-methyl-3-benzylimidazolium chloride, 2-methylimidazoline, and 2-phenylimidazoline; and adducts of the above-mentioned imidazole compound and epoxy resin.

(A) As the imidazole-based compound, a commercially available product may be used. (A) Commercially available imidazole compounds include, for example, "1B2PZ", "2E4MZ", "2MZA-PW", "2MZ-OK", "2MA-OK", and "2MA-" manufactured by Shikoku Kasei Kogyo Co., Ltd. OK-PW”, “2PHZ”, “2PHZ-PW”, “Cl1Z”, “Cl1Z-CN”, “Cl1Z-CNS”, “C11Z-A”; "P200-H50" manufactured by Mitsubishi Chemical Corporation, etc. are mentioned. (A) Imidazole-based compounds may be used individually or in combination of two or more types.

The amount of the imidazole-based compound (A) in the resin composition is preferably 0.01 mass% or more, more preferably 0.02 mass% or more, and particularly preferably 0.03 mass% or more, based on 100 mass% of non-volatile components of the resin composition. and is preferably 1 mass% or less, more preferably 0.5 mass% or less, and particularly preferably 0.1 mass% or less.

The amount of the imidazole-based compound (A) in the resin composition is preferably 0.01 mass% or more, more preferably 0.05 mass% or more, and particularly preferably 0.1 mass% or more, based on 100 mass% of the resin component of the resin composition. , Preferably it is 5 mass % or less, more preferably 2 mass % or less, and especially preferably 1 mass % or less. The resin component of the resin composition refers to components excluding the (C) inorganic filler described later among the non-volatile components of the resin composition.

The resin composition usually contains (B) a thermosetting resin. (B) As the thermosetting resin, a resin that can react when heat is applied to form a bond and harden the resin composition can be used. (B) Thermosetting resins include, for example, epoxy resins, phenol resins, activated ester resins, carbodiimide resins, acid anhydride resins, amine resins, benzoxazine resins, cyanate resins, and thiol resins. (B) Thermoplastic resin may be used individually or in combination of two or more types.

The epoxy resin may be a resin having an epoxy group. As epoxy resins, for example, bixylenol type epoxy resin, bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, bisphenol AF type epoxy resin, dicyclopentadiene type epoxy resin, trisphenol type epoxy resin. Resin, naphthol novolac type epoxy resin, phenol novolak type epoxy resin, tert-butyl-catechol type epoxy resin, naphthalene type epoxy resin, naphthol type epoxy resin, anthracene type epoxy resin, glycidylamine type epoxy resin, glycidyl Diel ester type epoxy resin, cresol novolak type epoxy resin, phenol aralkyl type epoxy resin, biphenyl type epoxy resin, linear aliphatic epoxy resin, epoxy resin with butadiene structure, alicyclic epoxy resin, heterocyclic epoxy resin, spiro ring containing Epoxy resin, cyclohexane type epoxy resin, cyclohexanedimethanol type epoxy resin, naphthylene ether type epoxy resin, trimethylol type epoxy resin, tetraphenylethane type epoxy resin, isocyanurate type epoxy resin, phenolphthalimidine type epoxy resin. etc. can be mentioned. One type of epoxy resin may be used alone, or two or more types may be used in combination.

The epoxy resin preferably contains an epoxy resin containing an aromatic structure from the viewpoint of obtaining an insulating layer with excellent heat resistance. An aromatic structure is a chemical structure generally defined as aromatic, and also includes polycyclic aromatics and aromatic heterocycles. Examples of the epoxy resin containing an aromatic structure include bisphenol A-type epoxy resin, bisphenol F-type epoxy resin, bisphenol S-type epoxy resin, bisphenol AF-type epoxy resin, dicyclopentadiene-type epoxy resin, and trisphenol-type epoxy resin. , naphthol novolak-type epoxy resin, phenol novolak-type epoxy resin, tert-butyl-catechol-type epoxy resin, naphthalene-type epoxy resin, naphthol-type epoxy resin, anthracene-type epoxy resin, bixylenol-type epoxy resin, glycerol having an aromatic structure. Cydylamine type epoxy resin, glycidyl ester type epoxy resin with an aromatic structure, cresol novolac type epoxy resin, biphenyl type epoxy resin, linear aliphatic epoxy resin with an aromatic structure, epoxy with a butadiene structure with an aromatic structure. Resin, alicyclic epoxy resin with an aromatic structure, heterocyclic epoxy resin, spiro ring-containing epoxy resin with an aromatic structure, cyclohexanedimethanol type epoxy resin with an aromatic structure, naphthylene ether type epoxy resin, trimethyl with an aromatic structure All-type epoxy resins, tetraphenylethane-type epoxy resins having an aromatic structure, etc. can be mentioned.

The resin composition preferably contains an epoxy resin having two or more epoxy groups in one molecule. With respect to 100% by mass of non-volatile components of the entire epoxy resin, the proportion of the epoxy resin having two or more epoxy groups in one molecule is preferably 50% by mass or more, more preferably 60% by mass or more, particularly preferably 70% by mass. It is more than %.

Epoxy resins include epoxy resins that are liquid at a temperature of 20°C (hereinafter also referred to as “liquid epoxy resins”) and epoxy resins that are solid at a temperature of 20°C (hereinafter also referred to as “solid epoxy resins”). The resin composition may contain only a liquid epoxy resin as an epoxy resin, may contain only a solid epoxy resin, or may contain a combination of a liquid epoxy resin and a solid epoxy resin.

As the liquid epoxy resin, a liquid epoxy resin having two or more epoxy groups in one molecule is preferable.

Liquid epoxy resins include bisphenol A-type epoxy resin, bisphenol F-type epoxy resin, bisphenol AF-type epoxy resin, naphthalene-type epoxy resin, glycidyl ester-type epoxy resin, glycidylamine-type epoxy resin, and phenol novolac-type epoxy resin. , alicyclic epoxy resins having an ester skeleton, cyclohexane-type epoxy resins, cyclohexanedimethanol-type epoxy resins, and epoxy resins having a butadiene structure are preferable.

Specific examples of the liquid epoxy resin include "HP4032", "HP4032D", and "HP4032SS" (naphthalene type epoxy resin) manufactured by DIC Corporation; "828US", "828EL", "jER828EL", "825", and "Epicoat 828EL" (bisphenol A type epoxy resin) manufactured by Mitsubishi Chemical Corporation; “jER807” and “1750” (bisphenol F-type epoxy resin) manufactured by Mitsubishi Chemical Corporation; “jER152” (phenol novolac type epoxy resin) manufactured by Mitsubishi Chemical Corporation; “630”, “630LSD”, and “604” (glycidylamine type epoxy resin) manufactured by Mitsubishi Chemical Corporation; “ED-523T” manufactured by ADEKA (glycirol type epoxy resin); “EP-3950L” and “EP-3980S” (glycidylamine type epoxy resin) manufactured by ADEKA; “EP-4088S” manufactured by ADEKA (dicyclopentadiene type epoxy resin); “ZX1059” manufactured by Nittetsu Chemical & Materials (mixture of bisphenol A-type epoxy resin and bisphenol F-type epoxy resin); “EX-721” (glycidyl ester type epoxy resin) manufactured by Nagase Chemtex Corporation; “Celoxide 2021P” manufactured by Daicel Corporation (alicyclic epoxy resin with an ester skeleton); “PB-3600” manufactured by Daicel Corporation, “JP-100” and “JP-200” manufactured by Nippon Soda Corporation (epoxy resin with a butadiene structure); “ZX1658” and “ZX1658GS” (liquid 1,4-glycidylcyclohexane type epoxy resin) manufactured by Nittetsu Chemical & Materials, and “YX8000” (hydrogenated bisphenol A type epoxy resin) manufactured by Mitsubishi Chemical Corporation. I can hear it. These may be used individually or in combination of two or more types.

As a solid epoxy resin, a solid epoxy resin having 3 or more epoxy groups per molecule is preferable, and an aromatic solid epoxy resin having 3 or more epoxy groups per molecule is more preferable.

As solid epoxy resins, xylenol-type epoxy resin, naphthalene-type epoxy resin, naphthalene-type tetrafunctional epoxy resin, naphthol novolak-type epoxy resin, cresol novolak-type epoxy resin, dicyclopentadiene-type epoxy resin, and trisphenol-type epoxy resin. , naphthol type epoxy resin, biphenyl type epoxy resin, naphthylene ether type epoxy resin, anthracene type epoxy resin, bisphenol A type epoxy resin, bisphenol AF type epoxy resin, phenol aralkyl type epoxy resin, tetraphenylethane type epoxy resin, phenol Phthalimidine type epoxy resin is preferred.

Specific examples of the solid epoxy resin include "HP4032H" (naphthalene type epoxy resin) manufactured by DIC Corporation; “HP-4700” and “HP-4710” (naphthalene type tetrafunctional epoxy resin) manufactured by DIC Corporation; "N-690" (cresol novolac type epoxy resin) manufactured by DIC Corporation; "N-695" (cresol novolac type epoxy resin) manufactured by DIC Corporation; "HP-7200", "HP-7200HH", "HP-7200H", and "HP-7200L" (dicyclopentadiene type epoxy resin) manufactured by DIC Corporation; "EXA-7311", "EXA-7311-G3", "EXA-7311-G4", "EXA-7311-G4S", and "HP6000" (naphthylene ether type epoxy resin) manufactured by DIC Corporation; “EPPN-502H” manufactured by Nihon Kayaku Co., Ltd. (trisphenol type epoxy resin); "NC7000L" (naphthol novolac type epoxy resin) manufactured by Nihon Kayaku Co., Ltd.; "NC3000H", "NC3000", "NC3000L", "NC3000FH", and "NC3100" (biphenyl type epoxy resin) manufactured by Nihon Kayaku Co., Ltd.; “ESN475V” and “ESN4100V” (naphthalene type epoxy resin) manufactured by Nittetsu Chemical & Materials Co., Ltd.; “ESN485” (naphthol type epoxy resin) manufactured by Nittetsu Chemical &Materials; “ESN375” (dihydroxynaphthalene type epoxy resin) manufactured by Nittetsu Chemical &Materials; "YX4000H", "YX4000", "YX4000HK", and "YL7890" (bixylenol type epoxy resin) manufactured by Mitsubishi Chemical Corporation; “YL6121” (biphenyl type epoxy resin) manufactured by Mitsubishi Chemical Corporation; “YX8800” (anthracene type epoxy resin) manufactured by Mitsubishi Chemical Corporation; “YX7700” (phenol aralkyl type epoxy resin) manufactured by Mitsubishi Chemical Corporation; “PG-100” and “CG-500” manufactured by Osaka Gas Chemical Co., Ltd.; “YL7760” (bisphenol AF type epoxy resin) manufactured by Mitsubishi Chemical Corporation; “YL7800” (fluorene type epoxy resin) manufactured by Mitsubishi Chemical Corporation; "jER1010" (bisphenol A type epoxy resin) manufactured by Mitsubishi Chemical Corporation; “jER1031S” (tetraphenylethane type epoxy resin) manufactured by Mitsubishi Chemical Corporation; "WHR991S" (phenolphthalimidine type epoxy resin) manufactured by Nihon Kayaku Co., Ltd., etc. are mentioned. These may be used individually or in combination of two or more types.

As an epoxy resin, when using a combination of liquid epoxy resin and solid epoxy resin, their mass ratio (liquid epoxy resin:solid epoxy resin) is preferably 20:1 to 1:20, more preferably 10:1 to 10:1. 1:10, particularly preferably 7:1 to 1:7.

The epoxy equivalent weight of the epoxy resin is preferably 50 g/eq. to 5,000 g/eq., more preferably 60 g/eq. to 3,000 g/eq., more preferably 80 g/eq. to 2,000 g/eq., particularly preferably 110 g/eq. to 1,000 g/eq. Epoxy equivalent weight represents the mass of resin per equivalent of epoxy group. This epoxy equivalent can be measured according to JIS K7236.

The weight average molecular weight (Mw) of the epoxy resin is preferably 100 to 5,000, more preferably 250 to 3,000, and still more preferably 400 to 1,500. The weight average molecular weight of the resin can be measured as a value in terms of polystyrene by gel permeation chromatography (GPC).

The amount of epoxy resin in the resin composition is preferably 1% by mass or more, more preferably 5% by mass or more, particularly preferably 10% by mass or more, based on 100% by mass of non-volatile components in the resin composition. It is 50 mass% or less, more preferably 40 mass% or less, and especially preferably 30 mass% or less.

The amount of epoxy resin in the resin composition is preferably 10% by mass or more, more preferably 30% by mass or more, particularly preferably 50% by mass or more, based on 100% by mass of the resin component in the resin composition, and preferably 90% by mass or more. It is % by mass or less, more preferably 85 mass % or less, especially preferably 80 mass % or less.

The phenol resin may be a resin having one or more, preferably two or more, hydroxyl groups per molecule bonded to an aromatic ring such as a benzene ring or naphthalene ring. From the viewpoint of heat resistance and water resistance, a phenol resin having a novolak structure is preferable. Furthermore, from the viewpoint of adhesion, a nitrogen-containing phenol resin is preferable, and a triazine skeleton-containing phenol resin is more preferable. Among them, a phenol novolak resin containing a triazine skeleton is preferable from the viewpoint of highly satisfying heat resistance, water resistance, and adhesion.

Specific examples of phenolic resins include, for example, “MEH-7700”, “MEH-7810”, and “MEH-7851” manufactured by Meiwa Kasei Co., Ltd., and “NHN”, “CBN”, and “GPH” manufactured by Nihon Kayaku Co., Ltd. , “SN-170”, “SN-180”, “SN-190”, “SN-475”, “SN-485”, “SN-495”, “SN-375” manufactured by Nittetsu Chemical & Materials Co., Ltd. ”, “SN-395”, “LA-7052”, “LA-7054”, “LA-3018”, “LA-3018-50P”, “LA-1356”, “TD2090”, “TD” manufactured by DIC Corporation -2090-60M” and the like. One type of phenol resin may be used alone, or two or more types may be used in combination.

The amount of phenol resin in the resin composition is preferably 0.1% by mass or more, preferably 0.5% by mass or more, particularly preferably 1% by mass or more, based on 100% by mass of non-volatile components in the resin composition, and preferably 50% by mass or more. It is % by mass or less, more preferably 40 mass% or less, and particularly preferably 30 mass% or less.

The amount of phenol resin in the resin composition is preferably 0.1% by mass or more, preferably 1% by mass or more, particularly preferably 3% by mass or more, and preferably 60% by mass, based on 100% by mass of the resin component in the resin composition. % or less, more preferably 50 mass% or less, particularly preferably 40 mass% or less.

The active ester resin may be a resin having one or more active ester groups in one molecule. The active ester group may be an ester bond directly bonded to an aromatic ring. Active ester resins are generally compounds having two or more active ester groups with high reaction activity per molecule, such as phenol esters, thiophenol esters, N-hydroxyamine esters, and esters of heterocyclic hydroxy compounds. This is desirable. The active ester resin is preferably obtained by a condensation reaction of a carboxylic acid compound and/or a thiocarboxylic acid compound and a hydroxy compound and/or a thiol compound. Particularly from the viewpoint of improving heat resistance, active ester resins obtained from carboxylic acid compounds and hydroxy compounds are preferable, and active ester resins obtained from carboxylic acid compounds, phenol compounds, and/or naphthol compounds are more preferable. Examples of carboxylic acid compounds include benzoic acid, acetic acid, succinic acid, maleic acid, itaconic acid, phthalic acid, isophthalic acid, terephthalic acid, and pyromellitic acid. As phenol compounds or naphthol compounds, for example, hydroquinone, resorcin, bisphenol A, bisphenol F, bisphenol S, phenolphthaline, methylated bisphenol A, methylated bisphenol F, methylated bisphenol S, phenol, o-cresol, m- Cresol, p-cresol, catechol, α-naphthol, β-naphthol, 1,5-dihydroxynaphthalene, 1,6-dihydroxynaphthalene, 2,6-dihydroxynaphthalene, dihydroxybenzophenone, Trihydroxybenzophenone, tetrahydroxybenzophenone, phloroglucine, benzenetriol, dicyclopentadiene type diphenol compound, phenol novolak, etc. are mentioned. Here, “dicyclopentadiene-type diphenol compound” refers to a diphenol compound obtained by condensing two molecules of phenol with one molecule of dicyclopentadiene.

Specifically, the active ester resin includes a dicyclopentadiene type active ester resin, a naphthalene type active ester resin containing a naphthalene structure, an active ester resin containing an acetylate of phenol novolac, and a benzoylate of phenol novolak. The following active ester resins are preferable, and among them, at least one type selected from dicyclopentadiene-type active ester resins and naphthalene-type active ester resins is more preferable. As the dicyclopentadiene type active ester resin, an active ester resin containing a dicyclopentadiene type diphenol structure is preferable.

Commercially available active ester resins include, for example, active ester resins containing a dicyclopentadiene-type diphenol structure, such as "EXB9451", "EXB9460", "EXB9460S", "EXB-8000L", and "EXB-8000L-" 65M", "EXB-8000L-65TM", "HPC-8000L-65TM", "HPC-8000", "HPC-8000-65T", "HPC-8000H", "HPC-8000H-65TM" (manufactured by DIC) ); As an active ester resin containing a naphthalene structure, “HP-B-8151-62T”, “EXB-8100L-65T”, “EXB-8150-60T”, “EXB-8150-62T”, and “EXB-9416-70BK” , “HPC-8150-60T”, “HPC-8150-62T”, “EXB-8” (manufactured by DIC); As a phosphorus-containing active ester resin, "EXB9401" (manufactured by DIC Corporation); As an active ester resin which is an acetylated product of phenol novolak, "DC808" (manufactured by Mitsubishi Chemical Corporation); Examples of active ester resins that are benzoylates of phenol novolak include "YLH1026", "YLH1030", and "YLH1048" (manufactured by Mitsubishi Chemical Corporation); Examples of the active ester resin containing a styryl group and a naphthalene structure include "PC1300-02-65MA" (manufactured by Air Water). One type of activated ester resin may be used individually, or two or more types may be used in combination.

The amount of active ester resin in the resin composition is preferably 0.1% by mass or more, preferably 0.5% by mass or more, particularly preferably 1% by mass or more, based on 100% by mass of non-volatile components in the resin composition. It is 50 mass% or less, more preferably 40 mass% or less, and especially preferably 30 mass% or less.

The amount of active ester resin in the resin composition is preferably 0.1% by mass or more, preferably 1% by mass or more, particularly preferably 3% by mass or more, based on 100% by mass of the resin component in the resin composition, and preferably 60% by mass or more. It is % by mass or less, more preferably 50 mass % or less, especially preferably 40 mass % or less.

The carbodiimide resin may be a resin having one or more carbodiimide structures per molecule, preferably two or more carbodiimide structures. Examples of carbodiimide resin include biscarbodiimide, polycarbodiimide, and the like. Specific examples of biscabodiimide include aliphatic biscabodiimides such as tetramethylene-bis(t-butylcarbodiimide) and cyclohexanebis(methylene-t-butylcarbodiimide); Aromatic biscarbodiimide such as phenylene-bis(xylylcarbodiimide) can be mentioned. Specific examples of polycarbodiimide include polyhexamethylenecarbodiimide, polytrimethylhexamethylenecarbodiimide, polycyclohexylenecarbodiimide, poly(methylenebiscyclohexylenecarbodiimide), and poly(isophoronecarbodiimide). ), etc., aliphatic polycarbodiimide; Poly(phenylenecarbodiimide), poly(naphthylenecarbodiimide), poly(tolylenecarbodiimide), poly(methyldiisopropylphenylenecarbodiimide), poly(triethylphenylenecarbodiimide), poly(di Ethylphenylenecarbodiimide), poly(triisopropylphenylenecarbodiimide), poly(diisopropylphenylenecarbodiimide), poly(xylylenecarbodiimide), poly(tetramethylxylylenecarbodiimide), poly (methylenediphenylenecarbodiimide), poly[methylenebis(methylphenylene)carbodiimide], and other aromatic polycarbodiimides. Commercially available products of carbodiimide resin include, for example, “Carbodylight V-02B,” “Carbodylight V-03,” “Carbodylight V-04K,” and “Carbodylight V” manufactured by Nisshinbo Chemical Co., Ltd. -07” and “Carbody Light V-09”; “Stabaxol P”, “Stabaxol P400”, and “Hykazyl 510” manufactured by Rhein Chemistry, etc. can be mentioned. Carbodiimide resin may be used individually or in combination of two or more types.

The acid anhydride resin may be a resin having one or more acid anhydride groups in one molecule, and a resin having two or more acid anhydride groups in one molecule is preferred. Specific examples of acid anhydride resin include phthalic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, methyltetrahydrophthalic anhydride, methylhexahydrophthalic anhydride, methylnadic anhydride, hydrogenated methylnadic anhydride, trialkyltetrahydrophthalic anhydride, Dodecenyl succinic anhydride, 5-(2,5-dioxotetrahydro-3-furanyl)-3-methyl-3-cyclohexene-1,2-dicarboxylic acid anhydride, trimellitic anhydride, pyromellitic anhydride, Benzophenone tetracarboxylic acid dianhydride, biphenyltetracarboxylic acid dianhydride, naphthalenetetracarboxylic acid dianhydride, oxydiphthalic acid dianhydride, 3,3'-4,4'-diphenylsulfone tetracarboxylic acid dianhydride, 1,3,3a, 4,5,9b-hexahydro-5-(tetrahydro-2,5-dioxo-3-furanyl)-naphtho[1,2-C]furan-1,3-dione, ethylene glycol bis(an hydrotrimellitate) and polymer-type acid anhydrides such as styrene-maleic acid resin, which is a copolymerization of styrene and maleic acid. Commercially available acid anhydride resins include, for example, "HNA-100", "MH-700", "MTA-15", "DDSA", and "OSA" manufactured by Nippon Rika Corporation; “YH-306” and “YH-307” manufactured by Mitsubishi Chemical Corporation; “HN-2200” and “HN-5500” manufactured by Hitachi Kasei Corporation; “EF-30”, “EF-40”, “EF-60”, “EF-80” manufactured by Clay Valley, etc. are included. Acid anhydride resin may be used individually or in combination of two or more types.

The amine resin may be a resin having one or more amino groups, preferably two or more amino groups per molecule. Examples of amine resins include aliphatic amines, polyether amines, alicyclic amines, and aromatic amines. Among these, aromatic amines are preferable. The amine resin is preferably a primary amine or a secondary amine, and is more preferably a primary amine. Specific examples of amine resins include 4,4'-methylenebis(2,6-dimethylaniline), 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenylsulfone, and 3,3'-diaminodiphenylmethane. minodiphenyl sulfone, m-phenylenediamine, m-xylylenediamine, diethyltoluenediamine, 4,4'-diaminodiphenyl ether, 3,3'-dimethyl-4,4'-diaminobiphenyl , 2,2'-dimethyl-4,4'-diaminobiphenyl, 3,3'-dihydroxybenzidine, 2,2-bis(3-amino-4-hydroxyphenyl)propane, 3,3- Dimethyl-5,5-diethyl-4,4-diphenylmethanediamine, 2,2-bis(4-aminophenyl)propane, 2,2-bis(4-(4-aminophenoxy)phenyl)propane, 1,3-bis(3-aminophenoxy)benzene, 1,3-bis(4-aminophenoxy)benzene, 1,4-bis(4-aminophenoxy)benzene, 4,4'-bis(4) -aminophenoxy)biphenyl, bis(4-(4-aminophenoxy)phenyl)sulfone, and bis(4-(3-aminophenoxy)phenyl)sulfone. Examples of commercially available amine resins include “SEIKACURE-S” manufactured by Seika Corporation; "KAYABOND C-200S", "KAYABOND C-100", "Kayahard A-A", "Kayahard A-B", and "Kayahard A-S" manufactured by Nippon Kayaku Corporation; “Epicure W” manufactured by Mitsubishi Chemical Corporation; "DTDA" manufactured by Sumitomo Seika Co., Ltd., etc. are mentioned. Amine resins may be used individually or in combination of two or more types.

Specific examples of benzoxazine resin include “JBZ-OP100D” and “ODA-BOZ” manufactured by JFE Chemicals; “HFB2006M” manufactured by Showa Kobunshi Corporation; “P-d” and “F-a” manufactured by Shikoku Kasei Kogyo Corporation; and the like. One type of benzoxazine resin may be used alone, or two or more types may be used in combination.

Cyanate resin may be a resin having one or more cyanate groups per molecule, preferably two or more cyanate groups. Examples of the cyanate ester resin include bisphenol A dicyanate, polyphenol cyanate (oligo (3-methylene-1,5-phenylene cyanate)), and 4,4'-methylenebis (2,6- dimethylphenylcyanate), 4,4'-ethylidenediphenyldicyanate, hexafluorobisphenol A dicyanate, 2,2-bis(4-cyanate)phenylpropane, 1,1-bis(4- Cyanatephenylmethane), bis(4-cyanate-3,5-dimethylphenyl)methane, 1,3-bis(4-cyanatephenyl-1-(methylethylidene))benzene, bis(4-cyanate) Bifunctional cyanate resins such as natephenyl)thioether and bis(4-cyanatephenyl)ether, polyfunctional cyanate resins derived from phenol novolak and cresol novolac, etc., some of these cyanate resins are triazinated. Prepolymers, etc. can be mentioned. Specific examples of cyanate ester resin include "PT30" and "PT60" (both phenol novolak-type polyfunctional cyanate ester resins), "BA230", and "BA230S75" (part of bisphenol A dicyanate or prepolymers that have all been triadinated and become trimers), etc. Cyanate ester resin may be used individually or in combination of two or more types.

Examples of thiol resins include trimethylolpropanetris(3-mercaptopropionate), pentaerythritoltetrakis(3-mercaptobutyrate), and tris(3-mercaptopropyl)isocyanurate. You can. Thiol resins may be used individually or in combination of two or more types.

In a preferred embodiment, (B) the thermosetting resin includes an epoxy resin. In a more preferred embodiment, the thermosetting resin (B) includes a combination of an epoxy resin and a resin capable of curing the resin composition by reacting with the epoxy resin. A resin that can react with an epoxy resin and harden the resin composition is hereinafter also referred to as an “epoxy curing agent.” Examples of the epoxy curing agent include phenol resin, activated ester resin, carbodiimide resin, acid anhydride resin, amine resin, benzoxazine resin, cyanate ester resin, and thiol resin. Among epoxy curing agents, phenol resins and activated ester resins are preferred. Epoxy curing agents may be used individually or in combination of two or more types.

The active group equivalent weight of the epoxy curing agent is preferably 50 g/eq. to 3000 g/eq., more preferably 100 g/eq. to 1000 g/eq., more preferably 100 g/eq. to 500 g/eq., particularly preferably 100 g/eq. to 300 g/eq. The active group equivalent represents the mass of the epoxy curing agent per equivalent of the active group.

When using an epoxy resin and an epoxy curing agent in combination, the ratio of the epoxy group number of the epoxy resin and the active group number of the epoxy curing agent (“active group number of epoxy curing agent”/“epoxy group number of epoxy resin”) is preferably within a specific range. do. Specifically, the ratio (“number of active groups of epoxy curing agent”/“number of epoxy groups of epoxy resin”) is preferably 0.1 or more, more preferably 0.2 or more, further preferably 0.3 or more, and preferably 5.0 or less. , more preferably 3.0 or less, particularly preferably 1.5 or less. “Epoxy group number of an epoxy resin” refers to the sum of the mass of the non-volatile components of the epoxy resin present in the resin composition divided by the epoxy equivalent. In addition, the “active group number of the epoxy curing agent” refers to the sum of the mass of the non-volatile component of the epoxy curing agent present in the resin composition divided by the active group equivalent of the epoxy curing agent.

The amount of the thermosetting resin (B) in the resin composition is preferably 5% by mass or more, more preferably 10% by mass or more, especially preferably 20% by mass or more, based on 100% by mass of non-volatile components of the resin composition, Preferably it is 70 mass% or less, more preferably 60 mass% or less, and especially preferably 50 mass% or less.

The amount of the thermosetting resin (B) in the resin composition is preferably 60% by mass or more, more preferably 70% by mass or more, particularly preferably 80% by mass or more, based on 100% by mass of the resin component of the resin composition. It is preferably 99.9% by mass or less, more preferably 99% by mass or less.

The mass ratio of the (A) imidazole-based compound and (B) thermosetting resin ((B) thermosetting resin/(A) imidazole-based compound) in the resin composition is preferably 100 or more, more preferably 200 or more, even more preferably is 300 or more, particularly preferably 400 or less, preferably 1000 or less, more preferably 900 or less, further preferably 800 or less, particularly preferably 700 or less.

The resin composition may further contain (C) an inorganic filler. (C) The inorganic filler is usually contained in the resin composition in the form of particles.

(C) As the material for the inorganic filler, an inorganic compound is used. (C) Inorganic filler materials include, for example, silica, alumina, glass, cordierite, silicon oxide, barium sulfate, barium carbonate, talc, clay, mica powder, zinc oxide, hydrotalcite, boehmite, and hydroxide. Aluminum, magnesium hydroxide, calcium carbonate, magnesium carbonate, magnesium oxide, boron nitride, aluminum nitride, manganese nitride, aluminum borate, strontium carbonate, strontium titanate, calcium titanate, magnesium titanate, bismuth titanate, titanium oxide, zirconium oxide, barium titanate, Examples include barium zirconate titanate, barium zirconate, calcium zirconate, zirconium phosphate, and zirconium tungstate phosphate. Among these, silica and alumina are suitable, and silica is particularly suitable. Examples of silica include amorphous silica, fused silica, crystalline silica, synthetic silica, and hollow silica. Additionally, spherical silica is preferred as the silica. (C) Inorganic fillers may be used individually or in combination of two or more types.

(C) Commercially available inorganic fillers include, for example, “SP60-05” and “SP507-05” manufactured by Nittetsu Chemical &Materials; "YC100C", "YA050C", "YA050C-MJE", "YA010C", "SC2500SQ", "SO-C4", "SO-C2", "SO-C1", and "SC2050-SXF" manufactured by Adomatex. 」; “UFP-30” manufactured by Denka Corporation; “Actual writing NSS-3N”, “Actual writing NSS-4N”, and “Actual writing NSS-5N” manufactured by Tokuyama Corporation.

(C) The average particle diameter of the inorganic filler is preferably 0.01 μm or more, more preferably 0.05 μm or more, further preferably 0.1 μm or more, particularly preferably 0.2 μm or more, and preferably 10 μm or more. It is preferably 5 μm or less, more preferably 2 μm or less, and particularly preferably 1 μm or less.

(C) The average particle diameter of the inorganic filler can be measured by a laser diffraction/scattering method based on Mie scattering theory. Specifically, the particle diameter distribution of the inorganic filler can be prepared on a volume basis using a laser diffraction scattering type particle diameter distribution measuring device, and the median diameter can be measured as the average particle diameter. The measurement sample can be obtained by measuring 100 mg of inorganic filler and 10 g of methyl ethyl ketone in a vial bottle and dispersing them by ultrasonic waves for 10 minutes. Using a laser diffraction type particle size distribution measuring device, the particle size distribution of the inorganic filler based on the volume of the measurement sample was measured using a flow cell method with the light source wavelengths set to blue and red, and the median diameter was determined from the obtained particle size distribution. The average particle diameter can be calculated as . Examples of the laser diffraction type particle size distribution measuring device include "LA-960" manufactured by Horiba Seisakusho Co., Ltd.

(C) The specific surface area of the inorganic filler is preferably 0.1 m2/g or more, more preferably 0.5 m2/g or more, further preferably 1 m2/g or more, particularly preferably 3 m2/g or more, and is preferred. Preferably it is 100 m2/g or less, more preferably 70 m2/g or less, even more preferably 50 m2/g or less, and particularly preferably 40 m2/g or less. The specific surface area of the inorganic filler can be measured by adsorbing nitrogen gas on the surface of the sample using a specific surface area measuring device (Macsorb HM-1210 manufactured by Mountec) according to the BET method and calculating the specific surface area using the BET multi-point method. there is.

(C) The inorganic filler is preferably treated with a surface treatment agent from the viewpoint of improving moisture resistance and dispersibility. Examples of surface treatment agents include fluorine-containing silane coupling agents, aminosilane coupling agents, epoxysilane coupling agents, mercaptosilane coupling agents, silane coupling agents, alkoxysilanes, organosilazane compounds, and titanate coupling agents. Ringer, etc. can be mentioned. One type of surface treatment agent may be used individually, or two or more types may be used in arbitrary combination.

Commercially available surface treatment agents include, for example, "KBM403" (3-glycidoxypropyltrimethoxysilane), manufactured by Shin-Etsu Chemical Kogyo Co., Ltd., and "KBM803" (3-mercaptopropyltrimethoxysilane), manufactured by Shin-Etsu Chemical Co., Ltd. silane), “KBE903” (3-aminopropyltriethoxysilane) manufactured by Shin-Etsu Chemical Kogyoso, “KBM573” (N-phenyl-3-aminopropyltrimethoxysilane) manufactured by Shin-Etsu Chemical Kogyoso, Shin-Etsu Chemical “SZ-31” (hexamethyldisilazane) manufactured by Kogyo Corporation, “KBM103” (phenyltrimethoxysilane) manufactured by Shin-Etsu Chemical Kogyo Corporation, and “KBM-4803” (long chain epoxy type silane couple) manufactured by Shin-Etsu Chemical Kogyo Corporation ring agent), "KBM-7103" (3,3,3-trifluoropropyltrimethoxysilane) manufactured by Shin-Etsu Chemical Co., Ltd., etc.

The degree of surface treatment with a surface treatment agent is preferably within a specific range from the viewpoint of improving the dispersibility of the inorganic filler. Specifically, 100% by mass of the inorganic filler is preferably surface treated with 0.2% by mass to 5% by mass of a surface treatment agent, more preferably 0.2% by mass to 3% by mass of a surface treatment agent, It is more preferable that the surface is treated with 0.3% by mass to 2% by mass of a surface treatment agent.

The degree of surface treatment by a surface treatment agent can be evaluated by the amount of carbon per unit surface area of the inorganic filler. From the viewpoint of improving the dispersibility of the inorganic filler, the amount of carbon per unit surface area of the inorganic filler is preferably 0.02 mg/m 2 or more, more preferably 0.1 mg/m 2 or more, and still more preferably 0.2 mg/m 2 or more. On the other hand, from the viewpoint of preventing an increase in the melt viscosity of the resin composition, 1.0 mg/m 2 or less is preferable, 0.8 mg/m 2 or less is more preferable, and 0.5 mg/m 2 or less is still more preferable.

(C) The amount of carbon per unit surface area of the inorganic filler can be measured after the surface-treated inorganic filler is washed with a solvent (for example, methyl ethyl ketone (MEK)). Specifically, a sufficient amount of MEK as a solvent is added to the inorganic filler surface-treated with a surface treatment agent, and ultrasonic cleaning is performed at 25°C for 5 minutes. After removing the supernatant and drying the solid content, the amount of carbon per unit surface area of the inorganic filler can be measured using a carbon analyzer. As a carbon analyzer, "EMIA-320V" manufactured by Horiba Seisakusho, etc. can be used.

The amount of (C) inorganic filler in the resin composition is preferably 20% by mass or more, more preferably 40% by mass or more, especially preferably 60% by mass or more, based on 100% by mass of non-volatile components in the resin composition, Preferably it is 90 mass% or less, more preferably 85 mass% or less, and especially preferably 80 mass% or less.

The resin composition may further contain (D) a thermoplastic resin. This (D) thermoplastic resin does not include (A) an imidazole-based compound, (B) a thermosetting resin, or (C) an inorganic filler.

(D) Thermoplastic resins include, for example, phenoxy resin, polyimide resin, polyvinyl acetal resin, polyolefin resin, polybutadiene resin, polyamidoimide resin, polyetherimide resin, polysulfone resin, polyethersulfone resin, Polyphenylene ether resin, polycarbonate resin, polyether ether ketone resin, polyester resin, etc. can be mentioned. (D) Thermoplastic resins may be used individually, or may be used in combination of two or more types.

Examples of the phenoxy resin include bisphenol A skeleton, bisphenol F skeleton, bisphenol S skeleton, bisphenol acetophenone skeleton, novolac skeleton, biphenyl skeleton, fluorene skeleton, dicyclopentadiene skeleton, norbornene skeleton, and naphthalene skeleton. , a phenoxy resin having at least one skeleton selected from the group consisting of anthracene skeleton, adamantane skeleton, terpene skeleton, and trimethylcyclohexane skeleton. The terminal of the phenoxy resin may be any functional group such as a phenolic hydroxyl group or an epoxy group. Specific examples of the phenoxy resin include "1256" and "4250" manufactured by Mitsubishi Chemical Corporation (both are phenoxy resins containing a bisphenol A skeleton); “YX8100” manufactured by Mitsubishi Chemical Corporation (phenoxy resin containing bisphenol S skeleton); “YX6954” manufactured by Mitsubishi Chemical Corporation (phenoxy resin containing bisphenol acetophenone skeleton); “FX280” and “FX293” manufactured by Shinnittetsu Sumikin Kagaku Corporation; “YL7500BH30,” “YX6954BH30,” “YX7553,” “YX7553BH30,” “YL7769BH30,” “YL6794,” “YL7213,” “YL7290,” “YL7482,” and “YL78” manufactured by Mitsubishi Chemical Corporation. 91BH30” and the like.

Specific examples of the polyimide resin include “SLK-6100” manufactured by Shin-Etsu Chemical Co., Ltd., “Lika Coat SN20” and “Lica Coat PN20” manufactured by Shin-Nippon Rika Co., Ltd. Specific examples of polyimide resins include linear polyimides obtained by reacting bifunctional hydroxyl group-terminated polybutadiene, diisocyanate compounds, and tetrabasic acid anhydrides (polyimides described in Japanese Patent Application Laid-Open No. 2006-37083), and polysiloxane skeleton-containing polyimides. Modified polyimides such as mead (polyimide described in Japanese Patent Application Laid-Open No. 2002-12667 and Japanese Patent Application Laid-Open No. 2000-319386, etc.) can be mentioned.

Examples of the polyvinyl acetal resin include polyvinyl formal resin and polyvinyl butyral resin, with polyvinyl butyral resin being preferred. Specific examples of polyvinyl acetal resins include Denka Butyral 4000-2, Denka Butyral 5000-A, Denka Butyral 6000-C, and Denka Butyral 6000-EP manufactured by Denki Chemical Co., Ltd. ; Examples include S-Lec BH series, BX series (e.g. BX-5Z), KS series (e.g. KS-1), BL series, and BM series manufactured by Sekisui Kagaku Kogyo Co., Ltd.

Examples of polyolefin resins include ethylene-based copolymer resins such as low-density polyethylene, ultra-low-density polyethylene, high-density polyethylene, ethylene-vinyl acetate copolymer, ethylene-ethyl acrylate copolymer, and ethylene-methyl acrylate copolymer; and polyolefin-based polymers such as polypropylene and ethylene-propylene block copolymer.

Examples of the polybutadiene resin include hydrogenated polybutadiene skeleton-containing resin, hydroxyl group-containing polybutadiene resin, phenolic hydroxyl group-containing polybutadiene resin, carboxyl group-containing polybutadiene resin, acid anhydride group-containing polybutadiene resin, and epoxy group-containing poly. Examples include butadiene resin, isocyanate group-containing polybutadiene resin, urethane group-containing polybutadiene resin, and polyphenylene ether-polybutadiene resin.

Specific examples of polyamidoimide resin include “Viromax HR11NN” and “Viromax HR16NN” manufactured by Toyobo Co., Ltd. Specific examples of polyamideimide resins include modified polyamideimides such as "KS9100" and "KS9300" (polyamideimide containing a polysiloxane skeleton) manufactured by Hitachi Kasei Corporation.

Specific examples of the polyethersulfone resin include "PES5003P" manufactured by Sumitomo Chemical Co., Ltd.

Specific examples of polysulfone resins include polysulfone “P1700” and “P3500” manufactured by Solvay Advanced Polymers.

Specific examples of polyphenylene ether resin include "NORYL SA90" manufactured by SABIC. Specific examples of polyetherimide resin include “Ultem” manufactured by GE Corporation.

Examples of the polycarbonate resin include carbonate resin containing a hydroxy group, carbonate resin containing a phenolic hydroxyl group, carbonate resin containing a carboxy group, carbonate resin containing an acid anhydride group, carbonate resin containing an isocyanate group, carbonate resin containing a urethane group, etc. You can. Specific examples of polycarbonate resin include “FPC0220” manufactured by Mitsubishi Gas Chemicals, “T6002” and “T6001” (polycarbonate diol) manufactured by Asahi Kasei Chemicals, and “C-1090” and “C-2090” manufactured by Kuraray Corporation. ", "C-3090" (polycarbonate diol), etc. Specific examples of polyetheretherketone resin include "Sumipro K" manufactured by Sumitomo Chemical Co., Ltd.

Examples of polyester resin include polyethylene terephthalate resin, polyethylene naphthalate resin, polybutylene terephthalate resin, polybutylene naphthalate resin, polytrimethylene terephthalate resin, polytrimethylene naphthalate resin, and polycyclohexanedimethyl. Terephthalate resin, etc. can be mentioned.

(D) The weight average molecular weight (Mw) of the thermoplastic resin is preferably greater than 5,000, more preferably 8,000 or more, further preferably 10,000 or more, particularly preferably 20,000 or more, preferably 100,000 or less, more preferably Preferably it is 70,000 or less, more preferably 60,000 or less, and particularly preferably 50,000 or less.

The amount of the thermoplastic resin (D) in the resin composition is preferably 0.01 mass% or more, more preferably 0.1 mass% or more, especially preferably 0.2 mass% or more, based on 100 mass% of non-volatile components in the resin composition, Preferably it is 20 mass% or less, more preferably 10 mass% or less, and especially preferably 5 mass% or less.

The amount of the thermoplastic resin (D) in the resin composition is preferably 0.1% by mass or more, more preferably 0.5% by mass or more, particularly preferably 1% by mass or more, based on 100% by mass of the resin component in the resin composition. It is preferably 30% by mass or less, more preferably 20% by mass or less, and particularly preferably 10% by mass or less.

The resin composition may further contain (E) a flame retardant. (E) Flame retardants do not include those corresponding to the above-mentioned (A) imidazole compounds, (B) thermosetting resins, (C) inorganic fillers, or (D) thermoplastic resins. (E) Examples of the flame retardant include phosphazene compounds, organophosphorus flame retardants, organic nitrogen-containing phosphorus compounds, nitrogen compounds, silicone flame retardants, and metal hydroxides. One type of flame retardant may be used individually or two or more types may be used in combination.

Examples of the flame retardant include "SPH-100", "SPS-100", "SPB-100", and "SPE-100" (phosphazenes) manufactured by Otsuka Chemical Co., Ltd.; “FP-100”, “FP-110”, “FP-300”, and “FP-400” (phosphazenes) manufactured by Fushimi Seiyakusho Co., Ltd.; “HCA-NQ”, “HCA-HQ”, and “HCA-HQ-HST” (phosphinic acid ester (containing phenolic hydroxyl group)) manufactured by Sanko Corporation; Examples include “PX-200,” “PX-201,” “PX-202,” “CR-733S,” “CR-741,” and “CR-747” (phosphoric acid ester) manufactured by Daihachi Chemical Co., Ltd. You can.

The amount of the flame retardant (E) in the resin composition is preferably 0.1 mass% or more, more preferably 0.2 mass% or more, and even more preferably 0.3 mass% or more, based on 100 mass% of non-volatile components in the resin composition. The upper limit is preferably 5 mass% or less, more preferably 3 mass% or less, and even more preferably 1 mass% or less.

The resin composition may further contain (F) optional additives. (F) Optional additives include, for example, curing catalysts other than imidazole-based compounds; radically polymerizable compounds; Organometallic compounds such as organic copper compounds, organic zinc compounds, and organic cobalt compounds; Colorants such as phthalocyanine blue, phthalocyanine green, iodine green, diazo yellow, crystal violet, titanium oxide, and carbon black; Polymerization inhibitors such as hydroquinone, catechol, pyrogallol, and phenothiazine; Leveling agents such as silicone-based leveling agents and acrylic polymer-based leveling agents; Thickeners such as bentone and montmorillonite; Antifoaming agents such as silicone-based defoaming agents, acrylic-based defoaming agents, fluorine-based defoaming agents, and vinyl resin-based defoaming agents; UV absorbers such as benzotriazole-based UV absorbers; Adhesion improvers such as urea silane; Adhesion imparting agents such as triazole-based adhesion imparting agents, tetrazole-based adhesion imparting agents, and triazine-based adhesion imparting agents; Antioxidants such as hindered phenol antioxidants; Fluorescent whitening agents such as stilbene derivatives; Surfactants such as fluorine-based surfactants and silicone-based surfactants; Dispersants such as phosphoric acid ester-based dispersants, polyoxyalkylene-based dispersants, acetylene-based dispersants, silicone-based dispersants, anionic dispersants, and cationic dispersants; Stabilizers such as borate-based stabilizers, titanate-based stabilizers, aluminate-based stabilizers, zirconate-based stabilizers, isocyanate-based stabilizers, carboxylic acid-based stabilizers, and carboxylic acid anhydride-based stabilizers; Photopolymerization initiation aids such as tertiary amines; Photosensitizers such as pyrazolines, anthracenes, coumarins, xanthone types, and thioxanthone types can be mentioned. (F) Optional additives may be used individually or in combination of two or more types.

The resin composition is a combination of non-volatile components such as the above-mentioned (A) imidazole compound, (B) thermosetting resin, (C) inorganic filler, (D) thermoplastic resin, (E) flame retardant, and (F) optional additives. Therefore, the solvent (G) may be further included as an optional volatile component. (G) As a solvent, an organic solvent is usually used. Examples of organic solvents include ketone-based solvents such as acetone, methyl ethyl ketone, methyl isobutyl ketone, and cyclohexanone; Ester solvents such as methyl acetate, ethyl acetate, butyl acetate, isobutyl acetate, isoamyl acetate, methyl propionate, ethyl propionate, and γ-butyrolactone; ether solvents such as tetrahydropyran, tetrahydrofuran, 1,4-dioxane, diethyl ether, diisopropyl ether, dibutyl ether, diphenyl ether, and anisole; Alcohol-based solvents such as methanol, ethanol, propanol, butanol, and ethylene glycol; Ether ester solvents such as 2-ethoxyethyl acetate, propylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether acetate, ethyl diglycol acetate, γ-butyrolactone, and methyl methoxypropionate; Ester alcohol solvents such as methyl lactate, ethyl lactate, and methyl 2-hydroxyisobutyrate; Ether alcohol solvents such as 2-methoxypropanol, 2-methoxyethanol, 2-ethoxyethanol, propylene glycol monomethyl ether, and diethylene glycol monobutyl ether (butylcarbitol); amide-based solvents such as N,N-dimethylformamide, N,N-dimethylacetamide, and N-methyl-2-pyrrolidone; Sulfoxide-based solvents such as dimethyl sulfoxide; Nitrile-based solvents such as acetonitrile and propionitrile; Aliphatic hydrocarbon-based solvents such as hexane, cyclopentane, cyclohexane, and methylcyclohexane; and aromatic hydrocarbon-based solvents such as benzene, toluene, xylene, ethylbenzene, and trimethylbenzene. (G) One type of solvent may be used individually, or two or more types may be used in combination.

(G) The amount of solvent is not particularly limited, but when all components in the resin composition are 100 mass%, for example, 60 mass% or less, 40 mass% or less, 30 mass% or less, 20 mass% or less, 15 mass% or less. % or less, 10 mass% or less, etc., and may be 0 mass%.

The thickness of the resin composition layer is preferably 100 μm or less, more preferably 80 μm or less, and still more preferably 50 μm or less from the viewpoint of reducing the thickness of the printed wiring board. The lower limit of the thickness of the resin composition layer is not particularly limited, but may be 5 μm or more, 10 μm or more, etc.

-Manufacturing method of resin sheet-

The manufacturing method of the resin sheet is not particularly limited. The resin sheet can be manufactured, for example, by a method that includes applying a resin composition onto a release layer of a support. When using a liquid (varnish-like) resin composition, the resin composition may be applied as is on the release layer of the support. Additionally, a solvent and a non-volatile component of the resin composition may be mixed to prepare a liquid (varnish-like) resin composition, and this may be applied onto the release layer. Examples of the solvent include the same solvent as (G) described as a component of the resin composition. Additionally, application may be performed using a coating device such as a die coater.

The method for producing a resin sheet may include drying the applied resin composition, if necessary. Drying may be performed by a drying method such as heating or hot air spraying. Drying conditions are not particularly limited, but drying is performed so that the solvent content in the resin composition layer is usually 10% by mass or less, preferably 5% by mass or less. Although it may vary depending on the boiling point of the solvent in the resin composition, for example, when using a resin composition containing 30% by mass to 60% by mass of solvent, drying at 50°C to 150°C for 3 to 10 minutes, A resin composition layer can be formed.

The manufacturing method of the resin sheet may further include an arbitrary process. For example, the method for producing a resin sheet may include bonding a resin composition layer and a protective film according to the support. The thickness of the protective film is not particularly limited, but is, for example, 1 μm to 40 μm. When bonding a protective film, adhesion of dust and scratches to the surface of the resin composition layer can be suppressed. Usually, the protective film is removed before laminating the resin sheet and the inner layer substrate in step (I).

[Process (I): Lamination of resin sheet and inner layer substrate]

A method for manufacturing a printed wiring board according to an embodiment of the present invention includes a step (I) of laminating a resin sheet on an inner layer substrate so that the resin composition layer is bonded to the inner layer substrate. The “inner layer substrate” used in step (I) is a member that becomes the substrate of the printed wiring board, for example, glass epoxy substrate, metal substrate, polyester substrate, polyimide substrate, BT resin substrate, and thermosetting polyphenylene. Ether substrates, etc. can be mentioned. Additionally, the substrate may have a conductor layer on one or both sides, and this conductor layer may be pattern-processed. An inner layer board with a conductor layer (circuit) formed on one or both sides of the board is also called an “inner layer circuit board.” Additionally, when manufacturing a printed wiring board, an intermediate product on which an insulating layer and/or a conductor layer will be additionally formed is also included in the “inner layer substrate.” If the printed wiring board is a circuit board with embedded components, an inner layer board with embedded components may be used.

Lamination of the inner layer substrate and the resin sheet can be performed, for example, by heat-pressing the resin sheet to the inner layer substrate from the support side. As a member for heat-pressing the resin sheet to the inner layer substrate (hereinafter also referred to as “heat-pressing member”), for example, a heated metal plate (SUS head plate, etc.) or metal roll (SUS roll, etc.) can be used. In addition, it is preferable not to press the heat-compression member directly on the resin sheet, but to press it through an elastic material such as heat-resistant rubber so that the resin sheet sufficiently follows the surface irregularities of the inner layer substrate.

Lamination of the inner layer substrate and the resin sheet may be performed by a vacuum lamination method. In the vacuum lamination method, the heat-pressing temperature is preferably in the range of 60°C to 160°C, more preferably in the range of 80°C to 140°C, and the heat-compression pressure is preferably in the range of 0.098 MPa to 1.77 MPa, more preferably 0.29 MPa to 0.29 MPa. It is in the range of 1.47 MPa, and the heat compression time is preferably in the range of 20 seconds to 400 seconds, more preferably in the range of 30 seconds to 300 seconds. Lamination is preferably carried out under reduced pressure conditions at a pressure of 26.7 hPa or less.

Lamination can be performed using a commercially available vacuum laminator. Examples of commercially available vacuum laminators include a vacuum pressurization laminator manufactured by Meiki Seisakusho, a vacuum applicator manufactured by Nikko Materials, and a batch vacuum pressurization laminator.

After lamination, the laminated resin sheets may be smoothed under normal pressure (atmospheric pressure), for example, by pressing a heat-pressing member from the support side. The press conditions for the smoothing treatment can be the same as the heat-pressing conditions for the above-described lamination. Smoothing treatment can be performed using a commercially available laminator. In addition, the lamination and smoothing treatment may be performed continuously using the commercially available vacuum laminator.

[Step (II): Thermal curing of the resin composition layer]

A method for manufacturing a printed wiring board according to an embodiment of the present invention includes a step (II) of thermosetting the resin composition layer in a nitrogen atmosphere after step (I). An insulating layer can be formed by thermosetting the resin composition layer. The formed insulating layer contains a cured product of the resin composition, and preferably contains only the cured product of the resin composition.

Thermal curing of the resin composition layer in step (II) is performed in a nitrogen atmosphere. Since the nitrogen atmosphere is filled with nitrogen gas, the oxygen concentration in the nitrogen atmosphere is low. The range of oxygen concentration in a nitrogen atmosphere is preferably 5 mass% or less, more preferably 3 mass% or less, particularly preferably 1 mass% or less, and ideally 0 mass%.

The pressure conditions of the nitrogen atmosphere in which step (II) is performed may be normal pressure or reduced pressure. In one example, the range of specific pressure conditions in the nitrogen atmosphere is preferably 0.075 mmHg (0.1 hPa) or more, more preferably 1 mmHg (1.3 hPa) or more, preferably 3751 mmHg (5000 hPa) or less, more preferably 1875 mmHg ( 2500hPa) or less.

Thermal curing of the resin composition layer in step (II) is

(II-2) performing heat treatment to maintain the resin composition layer at temperature T1,

(II-4) Performing heat treatment to maintain the resin composition layer at a temperature T2 higher than the temperature T1.

Included in this order: Hereinafter, the heat treatment process maintained at temperature T1 is also referred to as “precure process (II-2).” In addition, the heat treatment process maintained at temperature T2 is also called “post-cure process (II-4).”

Usually, before the precure process (II-2), the resin composition layer is at a temperature increase start temperature T0 that is lower than the temperature T1. The temperature increase start temperature T0 may be, for example, room temperature. Therefore, the process (II) may include a process (II-1) of increasing the temperature of the resin composition layer from the temperature increase start temperature T0 to the temperature T1 before the precure process (II-2). The range of the temperature increase rate in this step (II-1) is preferably 0.5°C/min or more, more preferably 1°C/min or more, and even more preferably 1.5°C/min or more from the viewpoint of significantly obtaining the effects of the present invention. ℃/min or higher, more preferably 2℃/min or higher, particularly preferably 2.5℃/min or higher, preferably 30℃/min or lower, more preferably 25℃/min or lower, even more preferably 20℃/min or higher. °C/min or less, more preferably 15°C/min or less, particularly preferably 10°C/min or less. The temperature increase rate in step (II-1) may be constant or may vary.

In the precure process (II-2), the resin composition layer is subjected to heat treatment maintained at the temperature T1. The heating temperature T1 in this precure process (II-2) is set to a temperature range higher than room temperature and lower than temperature T2. The specific range of the heating temperature T1 is preferably 50°C or higher, more preferably 60°C or higher, further preferably 70°C or higher, particularly preferably 80°C or higher, from the viewpoint of significantly obtaining the effects of the present invention. , preferably less than 150°C, more preferably less than 140°C, and even more preferably less than 130°C. In the precure process (II-2), maintaining the resin composition layer at a temperature T1 not only means maintaining the temperature of the resin composition layer at a constant temperature, but also maintaining the resin composition layer at a constant temperature in a range that does not significantly impair the effect of the present invention. This also includes fluctuations in temperature. For example, in the precure process (II-2), the temperature of the resin composition layer may vary within the range of ±10°C, ±8°C, or ±5°C. However, even when the temperature of the resin composition layer fluctuates in this way, it is preferable that the temperature of the resin composition layer in the precure process (II-2) is within the above preferred range, for example, within the range of 50°C to 150°C. . Among them, in the precure process (II-2), it is particularly preferable that the temperature of the resin composition layer is constant without fluctuation.

The range of time for maintaining the resin composition layer at the heating temperature T1 in the precure process (II-2) depends on the composition of the resin composition and the value of the heating temperature T1, but from the viewpoint of significantly obtaining the effect of the present invention, it is preferably It is 10 minutes or more, more preferably 15 minutes or more, especially preferably 20 minutes or more, preferably 150 minutes or less, more preferably 120 minutes or less, especially preferably 120 minutes or less.

Usually, before the post-cure process (II-4), the resin composition layer is at a temperature lower than temperature T2. Therefore, the process (II) may include a process (II-3) of heating the resin composition layer to the temperature T2 after the pre-cure process (II-2) and before the post-cure process (II-4). The range of the temperature increase rate in this step (II-3) is preferably 0.5°C/min or more, more preferably 1°C/min or more, and still more preferably 1.5°C/min or more from the viewpoint of significantly obtaining the effects of the present invention. ℃/min or higher, more preferably 2℃/min or higher, particularly preferably 2.5℃/min or higher, preferably 30℃/min or lower, more preferably 25℃/min or lower, even more preferably 20℃/min or higher. °C/min or less, more preferably 15°C/min or less, particularly preferably 10°C/min or less. The temperature increase rate in step (II-3) may be constant or may vary.

In the post-cure process (II-4), the resin composition layer is subjected to heat treatment maintained at the temperature T2. The heating temperature T2 in the post-cure process (II-4) is set to a temperature higher than the temperature T1. The specific range of the heating temperature T2 is preferably 150°C or higher, more preferably 155°C or higher, further preferably 160°C or higher, particularly preferably 170°C or higher, from the viewpoint of significantly obtaining the effects of the present invention. , preferably 250°C or lower, more preferably 230°C or lower, further preferably 220°C or lower, further preferably 210°C or lower, particularly preferably 200°C or lower. Maintaining the resin composition layer at a temperature T2 in the post-cure process (II-4) not only maintains the temperature of the resin composition layer at a constant temperature, but also maintains the resin composition layer within a range that does not significantly impair the effect of the present invention. This also includes fluctuations in temperature. For example, in the post-cure process (II-4), the temperature of the resin composition layer may vary within the range of ±10°C, ±8°C, or ±5°C. However, even when the temperature of the resin composition layer fluctuates in this way, the temperature of the resin composition layer in the post-cure process (II-4) is preferably within the above preferred range, for example, within the range of 150°C to 250°C. do. Among these, in the post-cure process (II-4), it is particularly preferable that the temperature of the resin composition layer is constant without fluctuation.

The difference T2-T1 between the heating temperature T1 in the pre-cure process (II-2) and the heating temperature T2 in the post-cure process (II-4) should be within a specific range from the viewpoint of significantly obtaining the effect of the present invention. desirable. Specifically, the difference T2-T1 is preferably 20°C or higher, more preferably 30°C or higher, particularly preferably 40°C or higher, and preferably 150°C or lower, more preferably 140°C or lower, further preferably Preferably it is 130°C or lower, particularly preferably 120°C or lower. When the temperature of the resin composition layer fluctuates in the pre-cure process (II-2) and/or the post-cure process (II-4), the median value of the temperature of the resin composition in the pre-cure process (II-2) and the post-cure process ( It is preferable that the difference in the median temperature of the resin composition in II-4) is within the above range.

The range of time for maintaining the resin composition layer at the heating temperature T2 in the post-cure process (II-4) depends on the composition of the resin composition and the value of the heating temperature T2, but from the viewpoint of significantly obtaining the effect of the present invention, it is preferably is 10 minutes or more, more preferably 15 minutes or more, particularly preferably 20 minutes or more, preferably 150 minutes or less, more preferably 120 minutes or less.

After heat treatment at temperature T1 in the pre-cure process (II-2), the resin composition layer may be cooled once and then subjected to heat treatment at heating temperature T2 in the post-cure process (II-4). Alternatively, after the heat treatment at temperature T1 in the precure step (II-2), the resin composition layer may be subjected to heat treatment at temperature T2 in the precure step (II-4) without cooling.

The heat treatment in the pre-cure process (II-2) and the heat treatment in the post-cure process (II-4) may be performed using the same heat treatment device. In addition, the heat treatment in the pre-cure process (II-2) is performed using a first heat treatment device, and the heat treatment in the post-cure process (II-4) is performed using a second heat treatment different from the first heat treatment device. It may be carried out using a device. The heat treatment device is not particularly limited as long as it can heat-cure the resin composition layer. As a heat processing device, for example, an oven, a hot press, etc. can be used. For example, after performing heat treatment in the pre-cure process (II-2) using an oven adjusted to temperature T1, the inner layer substrate and resin sheet are transferred to an oven controlled to temperature T2, and then subjected to heat treatment in the post-cure process (II-4) ) may be subjected to heat treatment. Alternatively, using a heat treatment device capable of temperature programming, heat treatment in the pre-cure process (II-2) is performed, then the temperature is raised from temperature T1 to temperature T2, and heat treatment in the post-cure process (II-4) is performed. It is okay to implement it.

Process (II) may further include any process in combination with the above-described processes (II-1) to (II-4). For example, step (II) may include a step of performing heat treatment to maintain the resin composition layer at a heating temperature other than the above temperatures T1 and T2. That is, step (II) is not limited to two steps of heat treatment and may include three or more steps of heat treatment.

[Step (III): Peeling of support]

The method for manufacturing a printed wiring board according to an embodiment of the present invention includes step (III) of peeling off the support after step (II). According to this embodiment, adhesion of the support and the insulating layer as the cured resin composition layer can be suppressed. Therefore, since peeling defects can be suppressed, smooth peeling of the support is possible.

Usually, the support is peeled off by pulling the support relative to the insulating layer. For example, the insulating layer and the inner layer substrate may be transported while the support is fixed, and the support may be peeled off. Additionally, for example, the support may be peeled by pulling it while the insulating layer and the inner layer substrate are fixed. Additionally, for example, the insulating layer and the inner layer substrate may be conveyed while the support is pulled, and the support may be peeled off.

Usually, peeling of the support is achieved by relatively stretching the support in a peeling direction at a specific angle with respect to the surface of the insulating layer. There is no particular limitation to the range of the angle formed by the peeling direction with respect to the surface of the insulating layer. From the viewpoint of smoothly proceeding the peeling of the support, the range of the angle is preferably 0° or more, preferably 70° or less, more preferably 60° or less, further preferably 50° or less, even more preferably is 40° or less, more preferably 30° or less, even more preferably 20° or less, particularly preferably 10° or less.

The temperature conditions for carrying out the peeling of the support are not particularly limited. From the viewpoint of reducing the energy required for manufacturing a printed wiring board, peeling of the support is usually performed at room temperature or a temperature close to it. Therefore, usually, after the above step (II), the inner layer substrate, the insulating layer, and the support are cooled, and then the support is peeled. The specific temperature range at which peeling of the support is performed is preferably in the range of 10°C or more to 40°C. In addition, the temperature reduction rate in the process of cooling from temperature T2 is not particularly limited, but is preferably 0.5°C/min or more, more preferably 1°C/min or more, even more preferably 1.5°C/min or more, even more preferably is 2°C/min or more, particularly preferably 2.5°C/min or more, preferably 30°C/min or less, more preferably 25°C/min or less, more preferably 20°C/min or less, even more preferably is 15°C/min or less, particularly preferably 10°C/min or less.

In the method for manufacturing a printed wiring board according to this embodiment, defective peeling between the insulating layer and the support is suppressed, and therefore it is possible to speed up the peeling speed of the support. From the viewpoint of contributing to the improvement of the production speed of printed wiring boards, it is desirable that the peeling speed is fast. The specific peeling speed range is preferably 1 m/min or more, more preferably 2 m/min or more, further preferably 3 m/min or more, further preferably 4 m/min or more, and particularly preferably 5 m/min or more. . The upper limit is not particularly limited, and may be, for example, 20 m/min or less, 10 m/min or less, etc.

[Process (IV): Drilling]

The method for manufacturing a printed wiring board according to an embodiment of the present invention may further include an arbitrary process. For example, the method for manufacturing a printed wiring board according to this embodiment may include a step (IV) of perforating the insulating layer. This step (IV) may be performed before step (III) or after step (III).

Step (IV) includes forming via holes and through holes in the insulating layer. The formation of holes may be performed using, for example, a drill, laser, or plasma, depending on the composition of the resin composition used to form the insulating layer. The dimensions and shape of the hole may be determined appropriately according to the design of the printed wiring board.

[Process (V): Harmonization processing]

The manufacturing method of a printed wiring board according to one embodiment of the present invention may include a step (V) of roughening the insulating layer. This step (V) is usually performed after step (III), but may be performed before step (III). Additionally, step (V) is preferably performed after step (IV). For example, after forming holes in the insulating layer in step (IV) and performing roughening treatment (V), step (III) of peeling off the support may be performed. When performing step (V) after forming the hole in step (IV), it is possible to remove resin residue (smear) that may remain in the hole.

The procedures and conditions of the roughening process are not particularly limited, and known procedures and conditions used when forming the insulating layer of a printed wiring board may be adopted. For example, the insulating layer may be roughened by performing swelling treatment with a swelling liquid, roughening treatment with an oxidizing agent, and neutralization treatment with a neutralizing liquid in this order.

Examples of the swelling liquid used in the roughening treatment include an alkaline solution and a surfactant solution, and an alkaline solution is preferred. As the alkaline solution, sodium hydroxide solution and potassium hydroxide solution are more preferable. Examples of commercially available swelling liquids include “Swelling Deep Securiganth P” and “Swelling Deep Securiganth SBU” manufactured by Atotech Japan. Swelling treatment with a swelling liquid can be performed, for example, by immersing the insulating layer in a swelling liquid of 30°C to 90°C for 1 minute to 20 minutes. From the viewpoint of suppressing swelling of the resin of the insulating layer to an appropriate level, it is preferable to immerse the insulating layer in a swelling liquid of 40°C to 80°C for 5 to 15 minutes.

Examples of the oxidizing agent used in the roughening treatment include an alkaline permanganate solution obtained by dissolving potassium permanganate or sodium permanganate in an aqueous solution of sodium hydroxide. The roughening treatment with an oxidizing agent such as an alkaline permanganic acid solution is preferably performed by immersing the insulating layer in an oxidizing agent solution heated to 60°C to 100°C for 10 to 30 minutes. Additionally, the concentration of permanganate in the alkaline permanganate solution is preferably 5% by mass to 10% by mass. Examples of commercially available oxidizing agents include alkaline permanganate solutions such as “Concentrate Compact CP” and “Dosing Solution Securiganth P” manufactured by Atotech Japan.

The neutralizing liquid used in the roughening treatment is preferably an acidic aqueous solution, and commercially available products include, for example, “Reduction Solution Securigant P” manufactured by Atotech Japan. Treatment with a neutralizing liquid can be performed, for example, by immersing the treated surface that has been roughened with an oxidizing agent in a neutralizing liquid at 30°C to 80°C for 5 to 30 minutes. In terms of workability, etc., a method of immersing an object that has been roughened with an oxidizing agent in a neutralizing liquid at 40°C to 70°C for 5 to 20 minutes is preferable.

In one example, the arithmetic mean roughness (Ra) of the surface of the insulating layer after roughening treatment is preferably 500 nm or less, more preferably 400 nm or less, and even more preferably 300 nm or less. The lower limit is not particularly limited and may be, for example, 1 nm or more, 2 nm or more, etc. In addition, the root mean square roughness (Rq) of the surface of the insulating layer after the roughening treatment is preferably 500 nm or less, more preferably 400 nm or less, and even more preferably 300 nm or less. The lower limit is not particularly limited and may be, for example, 1 nm or more, 2 nm or more, etc. The arithmetic mean roughness (Ra) and root mean square roughness (Rq) of the surface of the insulating layer can be measured using a non-contact surface roughness meter.

[Process (VI): Formation of conductor layer]

The method for manufacturing a printed wiring board according to one embodiment of the present invention may include a step (VI) of forming a conductor layer. In this step (VI), a conductor layer is usually formed on the insulating layer. Therefore, step (VI) is usually performed after step (III). In a preferred embodiment, steps (IV), (V), and (VI) are performed in this order.

The conductor material used in the conductor layer is not particularly limited. In a suitable embodiment, the conductor layer comprises one or more metals selected from the group consisting of gold, platinum, palladium, silver, copper, aluminum, cobalt, chromium, zinc, nickel, titanium, tungsten, iron, tin and indium. do. The conductor layer may be a single metal layer or an alloy layer. Examples of the alloy layer include a layer formed of an alloy of two or more metals selected from the above group (for example, nickel-chromium alloy, copper-nickel alloy, and copper-titanium alloy). Among them, from the viewpoint of versatility of forming the conductor layer, cost, ease of patterning, etc., a single metal layer of chromium, nickel, titanium, aluminum, zinc, gold, palladium, silver or copper, or a nickel-chromium alloy, copper-nickel alloy , an alloy layer of a copper-titanium alloy is preferable, and a single metal layer of chromium, nickel, titanium, aluminum, zinc, gold, palladium, silver or copper, or an alloy layer of a nickel-chromium alloy is more preferable, and a single metal layer of copper is more preferable. This is more preferable.

The conductor layer may have a single-layer structure or a multi-layer structure in which two or more single metal or alloy layers made of different types of metals or alloys are laminated. When the conductor layer has a multi-layer structure, the layer in contact with the insulating layer is preferably a single metal layer of chromium, zinc, or titanium, or an alloy layer of nickel-chromium alloy.

The thickness of the conductor layer depends on the desired design of the printed wiring board, but is generally 3 μm to 35 μm, preferably 5 μm to 30 μm.

The conductor layer may be formed, for example, by plating. For example, by plating the surface of the insulating layer using a conventionally known technique such as a semi-additive method or a full additive method, a conductor layer having a desired wiring pattern can be formed. From the viewpoint of manufacturing simplicity, the semi-additive method is preferable. Below, an example of forming a conductor layer by a semi-additive method will be shown.

First, a plating seed layer is formed on the surface of the insulating layer by electroless plating. Next, on the formed plating seed layer, a mask pattern is formed to expose a portion of the plating seed layer corresponding to the desired wiring pattern. After forming a metal layer by electrolytic plating on the exposed plating seed layer, the mask pattern is removed. Thereafter, the unnecessary plating seed layer is removed by a removal method such as etching, and a conductor layer having a desired wiring pattern can be formed.

If necessary, the formation of the insulating layer and the conductor layer in steps (I) to (VI) may be repeated to manufacture a multilayer printed wiring board.

[Other processes]

The method for manufacturing a printed wiring board according to an embodiment of the present invention may further include an arbitrary process in combination with the above-described processes.

For example, there are cases where a long resin sheet that is continuously conveyed in the longitudinal direction is used. In this case, the resin sheet is usually pulled out from a roll of the resin sheet, and the pulled out resin sheet is supplied onto the inner layer substrate. In this case, the method for manufacturing a printed wiring board may include a step of cutting the long resin sheet to an appropriate size. Cutting of the resin sheet may be performed before step (I) or after step (I).

For example, a resin sheet provided with a protective film that protects the resin composition layer may be used. The protective film is usually provided on the side opposite to the support of the resin composition layer. In this case, the manufacturing method of the printed wiring board may include a step of removing the protective film. Usually, removal of the protective film is performed before process (I).

[Purpose of printed wiring board]

A printed wiring board manufactured by the manufacturing method according to one embodiment of the present invention can be used for a wide range of purposes, and can be applied to semiconductor devices, for example. This semiconductor device includes the printed wiring board. Specific examples of semiconductor devices include various semiconductor devices used in electrical appliances (e.g., computers, mobile phones, digital cameras, televisions, etc.) and vehicles (e.g., motorcycles, automobiles, trams, ships, aircraft, etc.). You can. However, the printed wiring board may be applied to uses other than those mentioned above.

[Example]

Hereinafter, the present invention will be described in detail by giving examples. However, the present invention is not limited to the following examples. In the following description, “part” and “%” indicating quantity mean “part by mass” and “% by mass”, respectively, unless otherwise specified. In addition, the operations described below were performed in an atmospheric environment at room temperature and pressure (25°C, 1 atm) unless otherwise specified.

<Preparation Example 1: Preparation of support 1 having a release layer containing acrylic resin>

(Manufacture of acrylic resin (A1))

In a temperature-adjustable reactor equipped with a stirrer, thermometer, and condenser, 500 parts by mass of toluene, 80 parts by mass of stearyl methacrylate (18 carbon atoms in the alkyl chain), 15 parts by mass of methacrylic acid, and 2-hydroxyethyl methacrylate. 5 parts by mass and 1 part of azobisisobutyronitrile were added dropwise using a dropper at a reaction temperature of 85°C over 4 hours to carry out a polymerization reaction. Afterwards, the reaction was completed by aging at the same temperature for 2 hours, and acrylic resin (A) was obtained. This acrylic resin (A) was dissolved in water containing 5 mass% of isopropyl alcohol and 5 mass% of n-butyl cellosolve to obtain a resin solution containing acrylic resin (A1) as a release compound.

(Preparation of acrylic resin (B1))

In a stainless steel reaction vessel, methyl methacrylate (a), hydroxyethyl methacrylate (b), and aromatic urethane acrylate oligomer (“EBECRYL 220” manufactured by Daicel Allnex, number of acryloyl groups: 6) (c) ) was injected at a mass ratio of (a)/(b)/(c)=94/1/5. Additionally, sodium dodecylbenzenesulfonate as an emulsifier was added to the reaction vessel in an amount of 2 parts by mass for a total of 100 parts by mass of (a) + (b) + (c), and stirred to prepare a mixed solution (1).

Next, a reaction apparatus equipped with a stirrer, reflux cooling pipe, thermometer, and dropping funnel was prepared. 60 parts by mass of the liquid mixture (1), 200 parts by mass of isopropyl alcohol, and 5 parts by mass of potassium persulfate as a polymerization initiator were added to a reaction apparatus and heated to 60°C to prepare the liquid mixture (2). The mixed liquid (2) was kept heated at 60°C for 20 minutes.

Next, a mixed liquid (3) consisting of 40 parts by mass of liquid mixture (1), 50 parts by mass of isopropyl alcohol, and 5 parts by mass of potassium persulfate was prepared. Using a dropping funnel, the mixed liquid (3) was added dropwise to the mixed liquid (2) over 2 hours to prepare the mixed liquid (4).

After that, the liquid mixture (4) was kept heated at 60°C for 2 hours. After cooling the obtained liquid mixture (4) to 50°C or lower, it was transferred to a container equipped with a stirrer and pressure reduction equipment. To this container, 60 parts by mass of 25% aqueous ammonia and 900 parts by mass of pure water were added, and while heating to 60°C, isopropyl alcohol and unreacted monomers were recovered under reduced pressure, and acrylic resin (B1) as an optional resin dispersed in pure water was added. A composition containing was obtained.

(Preparation of release agent (1))

A resin solution containing an acrylic resin (A1) and a composition containing an acrylic resin (B1) are calculated as the mass ratio (solid mass ratio) of the acrylic resin (A1) and the acrylic resin (B1): (A1)/(B1)=20/ It was mixed to 80% to obtain an intermediate composition. Additionally, a fluorine-based surfactant (“Plascoat (registered trademark) RY-2” manufactured by Kokagaku Kogyo Co., Ltd.) was added to this intermediate composition in an amount of 0.1 parts by mass based on 100 parts by mass of the total intermediate composition, to form a liquid acrylic resin. Release agent (1) as a composition was obtained.

(Preparation of Support 1)

As a support substrate, a PET film (“T60” (thickness 38 μm) manufactured by Torres) was prepared. The release agent (1) was applied to one side of this support base using a gravure coater and dried to form a release layer with a thickness of 0.1 μm. Through the above operation, support 1 provided with a support base material and a release layer containing an acrylic resin was obtained.

<Preparation Example 2: Preparation of support 2 having a release layer not containing acrylic resin>

(Preparation of polyolefin resin (C1))

280 g of propylene-ethylene copolymer (propylene/ethylene = 99/1 (mass ratio)) was heated and melted in a nitrogen atmosphere in a four-necked flask. After that, the temperature inside the system was maintained at 170°C and while stirring, 5.5 g of dicumyl peroxide as a radical generator was added over 1 hour. After that, it was allowed to react for 1 hour. After completion of the reaction, the obtained reaction product was poured into a large amount of acetone to precipitate the resin. This resin was further washed with acetone several times to remove unreacted monomer. After that, the resin was dried under reduced pressure in a reduced pressure dryer to obtain polyolefin resin (C1).

(Preparation of aqueous dispersion of polyolefin resin (C1))

A stirrer equipped with a heater and a sealable, pressure-resistant 1 liter glass container was prepared. Into the glass container of this stirrer, 60 g of polyolefin resin (C1), 45.0 g of ethylene glycol-n-butyl ether (boiling point 171°C), and 188.1 g of distilled water were charged, and stirred at a rotation speed of the stirring blade of 300 rpm. did. It was heated after 10 minutes, the temperature inside the system was maintained at 140°C, and the mixture was stirred for an additional 60 minutes. After that, it was cooled to room temperature (about 25°C) by air cooling while stirring at a rotation speed of 300 rpm. The contents of the glass container were pressure filtered (air pressure 0.2 MPa) through a 300 mesh stainless steel filter (wire diameter 0.035 mm, plain weave) to obtain an aqueous dispersion of polyolefin resin (C1) (non-volatile component concentration 25% by mass). .

(Preparation of release agent (2))

The aqueous dispersion of the polyolefin resin (C1) was mixed with 100 parts by mass in terms of non-volatile components, and an aqueous polyvinyl alcohol solution (“JT-05” manufactured by Nippon Sakubi Pobal Co., Ltd., saponification rate of 94.5%, polymerization degree of 500, non-volatile component concentration of 8). 300 parts by mass (% by mass) in terms of non-volatile components were mixed, water was further added to adjust the final non-volatile component concentration to 6.0 mass %, and mold release agent (2) as a liquid polyolefin resin composition was obtained.

(Preparation of Support 2)

As a support substrate, a PET film (“T60” (thickness 38 μm) manufactured by Torres) was prepared. The release agent (2) was applied to one side of this support base using a gravure coater and dried to form a release layer with a thickness of 0.1 μm. Through the above operation, support 2 provided with a support base material and a release layer containing no acrylic resin was obtained.

<Preparation Example 3: Preparation of resin varnish A1>

6 parts of bisphenol-type epoxy resin (“ZX1059” manufactured by Shinnittetsu Sumikin Chemical Co., Ltd., epoxy equivalent weight of approximately 169 g/eq., 1:1 mixture of bisphenol A and bisphenol F), bixylenol-type epoxy resin (Mitsubishi Chemical Co., Ltd.) manufactured by “YX4000HK”, epoxy equivalent weight approximately 185 g/eq.), 9 parts, biphenyl type epoxy resin (“NC3000L” manufactured by Nippon Kayaku Co., Ltd., epoxy equivalent weight 288 g/eq.), 21 parts, and phenoxy resin (manufactured by Mitsubishi Chemical Company “ 10 parts of "YX7553BH30", a 1:1 solution of cyclohexanone:methyl ethyl ketone (MEK) containing 30% by mass of non-volatile components) is dissolved in a mixed solvent of 20 parts of solvent naphtha and 5 parts of cyclohexanone by heating while stirring to form a mixture. got it After cooling to room temperature, a cresol novolak-based curing agent containing a triazine skeleton (hydroxyl equivalent weight 151 g/eq., “LA-3018-50P” manufactured by DIC, 2-methoxypropanol with 50% non-volatile component) was added to the mixture. Solution) 6 parts, active ester curing agent (“HPC-8000-65T” manufactured by DIC, weight average molecular weight of about 2700, active group equivalent of about 223 g/eq., toluene solution of 65% by mass of non-volatile component) 20 parts, already Dazole-based curing accelerator (“1-benzyl-2-phenylimidazole” manufactured by Shikoku Kasei, MEK solution containing 5% by mass of non-volatile components) 2 parts, flame retardant (“HCA-HQ” manufactured by Sanko Corporation, 10-(2) , 2 parts of 5-dihydroxyphenyl)-10-hydro-9-oxa-10-phosphaphenanthrene-10-oxide (average particle diameter 2㎛) and 170 parts of inorganic filler were mixed and uniformly mixed with a high-speed rotating mixer. It was well dispersed. Thereafter, this mixture was filtered through a cartridge filter (“SHP050” manufactured by ROKITECHNO) to prepare resin varnish A1. As an inorganic filler, spherical silica (“SOC2” manufactured by Adomatex, average particle diameter 0.5 μm, specific surface area 5.8 m2/g) surface-treated with an aminosilane-based coupling agent (“KBM573” manufactured by Shin-Etsu Chemical Co., Ltd.) was used. .

<Preparation Example 4: Preparation of resin varnish A2>

30 parts of biphenyl type epoxy resin (epoxy equivalent weight approximately 290 g/eq., “NC3000H” manufactured by Nihon Kayaku Co., Ltd.), 5 parts of naphthalene type tetrafunctional epoxy resin (epoxy equivalent weight 162 g/eq., “HP-4700” manufactured by DIC Corporation) , 15 parts of liquid bisphenol A type epoxy resin (epoxy equivalent weight 180 g/eq., “jER828EL” manufactured by Mitsubishi Chemical Corporation), and phenoxy resin (weight average molecular weight 35000, “YX7553BH30” manufactured by Mitsubishi Chemical Corporation, non-volatile component 30 mass% 2 parts of methyl ethyl ketone (MEK) solution was heated and dissolved with stirring in a mixed solvent of 8 parts MEK and 8 parts cyclohexanone to obtain a mixture. To this mixture, 32 parts of a phenol novolak-based curing agent containing a triazine skeleton (phenolic hydroxyl group equivalent of about 124 g/eq., “LA-7054” manufactured by DIC, MEK solution with 60% by mass of non-volatile components), imidazole-based curing 2 parts of accelerator (“1-benzyl-2-phenylimidazole” manufactured by Shikoku Kasei, MEK solution with 5% by mass of non-volatile components), 160 parts of inorganic filler, polyvinyl butyral resin solution (weight average molecular weight 27000, glass) 2 parts (transition temperature 105°C, “KS-1” manufactured by Sekisui Kagaku Kogyo Co., Ltd., a mixed solution of ethanol and toluene with 15% by mass of non-volatile components and a mass ratio of 1:1) were mixed and uniformly dispersed with a high-speed rotating mixer. Thus, resin varnish A2 was prepared. As an inorganic filler, spherical silica (“SOC2” manufactured by Adomatex, average particle diameter 0.5 μm, specific surface area 5.8 m2/g) surface-treated with an aminosilane-based coupling agent (“KBM573” manufactured by Shin-Etsu Chemical Co., Ltd.) was used. .

<Preparation Example 5: Preparation of resin varnish B1>

2 parts of an imidazole-based curing accelerator (“1-benzyl-2-phenylimidazole” manufactured by Shikoku Kasei, MEK solution containing 5% by mass of non-volatile components), a phosphorus-based curing accelerator (“Tetrabutylphos” manufactured by Hoko Chemical Industries, Ltd. Resin varnish B1 was prepared in the same manner as in Production Example 3, except that it was changed to 2 parts (“phonium decanoate”, MEK solution containing 5% by mass of non-volatile components).

[Example 1]

(Manufacture of resin sheets)

Resin varnish A1 was uniformly applied to the surface of the support 1 obtained in Production Example 1 on the release layer side using a die coater, dried at 80°C to 120°C (average 100°C) for 6 minutes, and the support base material and mold release were formed. A resin sheet including the layer and the resin composition layer in this order was obtained. The thickness of the resin composition layer of the resin sheet was 40 μm.

(Laminate of resin sheet to inner layer circuit board)

Both sides of a glass cloth-based epoxy resin double-sided copper-clad laminate (copper foil thickness of 18 ㎛, substrate thickness of 0.8 mm, “R1515A” manufactured by Panasonic Denko) were immersed in an etchant (“CZ8100” manufactured by Meksa) to roughen the copper surface. The processing was performed to obtain an inner layer circuit board. A resin sheet was laminated on both sides of this inner layer circuit board using a batch type vacuum pressurization laminator (two-stage build-up laminator "CVP700" manufactured by Nichigo Morton Co., Ltd.). This laminate was performed so that the resin composition layer of the resin sheet was bonded to the inner layer circuit board. In addition, this laminate was performed by reducing the pressure for 30 seconds to bring the atmospheric pressure to 13 hPa or less, and then pressing under press conditions of 100°C, pressure of 0.74 MPa, and 30 seconds. Through the above laminate, a sample laminate was obtained including a support, a resin composition layer, an inner layer circuit board, a resin composition layer, and a support in this order.

(Curing of the resin composition layer)

After lamination of the resin composition layer and the inner circuit board, the sample laminate was placed in a nitrogen oven with the support attached. After input, the door was closed, and nitrogen was circulated until the oxygen concentration in the oven reached 0.5%. After confirming that the oxygen concentration in the oven was 0.5%, the resin composition layer was thermally cured under the following curing conditions. Specifically, in the curing conditions of Example 1, the temperature in the oven was raised from 30°C to 130°C at 10°C/min, then thermal curing was performed at 130°C for 30 minutes, and then the temperature was further increased to 170°C at 10°C/min. After raising the temperature to ℃, heat curing was further performed at 170℃ for 30 minutes. After that, the temperature was lowered to 30°C at 5°C/min, and the sample laminate was taken out from the nitrogen oven. Since the resin composition layer was heat-cured to form an insulating layer, an evaluation sample was obtained comprising the support, insulating layer, inner layer circuit board, insulating layer, and support in this order. The thickness of the insulating layer on the inner layer circuit was 40 μm.

(Peeling off of support)

The evaluation sample was cooled to room temperature (about 25°C), and then the support was peeled off. The peelability was good, and peeling of the support was achieved without damage to the support and the insulating layer. As a result of the peeling, a printed wiring board provided with an insulating layer and a support peeled from the insulating layer were obtained.

[Example 2]

A resin sheet, an evaluation sample, and a printed wiring board were manufactured in the same manner as in Example 1, except that Resin Varnish A1 was changed to Resin Varnish A2. In the process of peeling off the support, the peelability was good, and peeling of the support was achieved without damaging the support and the insulating layer.

[Comparative Example 1]

A resin sheet and evaluation sample were manufactured in the same manner as in Example 1, except that the curing conditions in the process of heat curing the resin composition layer were changed as follows. In the curing conditions of Comparative Example 1, after confirming that the oxygen concentration in the oven was 0.5%, the temperature in the oven was raised from 30°C to 200°C at 10°C/min, and then thermal curing was performed at 200°C for 90 minutes. I ordered it. After that, the temperature was lowered to 30°C at 5°C/min, the sample laminate was taken out from the nitrogen oven, and an evaluation sample was obtained.

The evaluation sample was cooled to room temperature (about 25°C), and then peeling of the support was attempted. However, the insulating layer and the support were adhered, making peeling difficult. Additionally, as a result of excessive peeling, the support was destroyed.

[Comparative Example 2]

A resin sheet and evaluation sample were produced in the same manner as in Comparative Example 1, except that Resin Varnish A1 was changed to Resin Varnish A2. The evaluation sample was cooled to room temperature (about 25°C), and then peeling of the support was attempted. However, the insulating layer and the support were adhered, making peeling difficult. Additionally, as a result of excessive peeling, the support was destroyed.

[Reference Example 1]

A resin sheet and an evaluation sample were produced in the same manner as in Comparative Example 1, except that Resin Varnish A1 was changed to Resin Varnish B. The evaluation sample was cooled to room temperature (about 25°C), and then the support was peeled off. The peelability was good, and peeling of the support was achieved without damage to the support and the insulating layer. As a result of the peeling, a printed wiring board provided with an insulating layer and a support peeled from the insulating layer were obtained.

[Reference Example 2]

A resin sheet and an evaluation sample were produced in the same manner as in Comparative Example 1, except that Support 1 was changed to Support 2. The evaluation sample was cooled to room temperature (about 25°C), and then the support was peeled off. The peelability was good, and peeling of the support was achieved without damage to the support and the insulating layer. As a result of the peeling, a printed wiring board provided with an insulating layer and a support peeled from the insulating layer were obtained.

[Reference Example 3]

A resin sheet and an evaluation sample were produced in the same manner as in Comparative Example 1, except that the support 1 was changed to a PET film (“E7004” manufactured by Toyobo Co., Ltd., thickness 38 μm) with a silicone release layer. The evaluation sample was cooled to room temperature (about 25°C), and then the support was peeled off. The peelability was good, and peeling of the support was achieved without damage to the support and the insulating layer. As a result of the peeling, a printed wiring board provided with an insulating layer and a support peeled from the insulating layer were obtained.

[Reference Example 4]

After introducing the sample laminate into the nitrogen oven, a resin sheet and an evaluation sample were produced in the same manner as Comparative Example 1, except that the resin composition layer was thermally cured in an air atmosphere without circulating nitrogen. The evaluation sample was cooled to room temperature (about 25°C), and then the support was peeled off. The peelability was good, and peeling of the support was achieved without damage to the support and the insulating layer. As a result of the peeling, a printed wiring board provided with an insulating layer and a support peeled from the insulating layer were obtained.

[result]

The results of the above examples, comparative examples and reference examples are shown in the table below. The meanings of the abbreviations in the “Judgment” section of the table below are as follows.

“OK”: The support and the insulating layer were not damaged, and the support could be peeled off.

“NG”: A peeling defect in which the support or insulating layer was destroyed occurred.

[examine]

From the results of Comparative Examples 1 and 2, it can be seen that peeling defects conventionally occur between the support and the resin composition layer. In addition, from the results of Reference Examples 1 to 4, the peeling defect is due to the mold release agent containing a (meth)acrylic resin, the resin composition layer containing a resin composition containing an imidazole-based compound, and heat curing. It can be seen that this is a specific task that occurs when all requirements for performance in a nitrogen atmosphere are met. From Examples 1 and 2, it was confirmed that the above specific problems could be solved by the production method of the present invention.

Claims (7)

(I) A process of laminating a resin sheet including a support provided with a release layer and a resin composition layer formed on the release layer of the support to the inner layer substrate so that the resin composition layer is bonded to the inner layer substrate,
(II) a process of thermosetting the resin composition layer in a nitrogen atmosphere, and
(III) Process of peeling off the support
A method of manufacturing a printed wiring board comprising in this order;
The release layer contains a (meth)acrylic resin;
The resin composition layer contains a resin composition containing an imidazole-based compound;
Production of a printed wiring board, wherein the thermal curing of the resin composition layer includes performing a heat treatment to maintain the resin composition layer at a temperature T1 and performing a heat treatment to maintain the resin composition layer at a temperature T2 higher than the temperature T1 in this order. method. The method for producing a printed wiring board according to claim 1, wherein the resin composition contains a thermosetting resin. 3. The method of claim 2, wherein the thermosetting resin is selected from the group consisting of epoxy resins, phenol resins, activated ester resins, carbodiimide resins, acid anhydride resins, amine resins, benzoxazine resins, cyanate ester resins and thiol resins. A method of manufacturing a printed wiring board comprising one or more types. The method of manufacturing a printed wiring board according to claim 1, wherein the temperature T2 is 150°C or higher. The method of manufacturing a printed wiring board according to claim 1, wherein the difference T2-T1 between the temperature T1 and the temperature T2 is 20°C or more. The method of manufacturing a printed wiring board according to claim 1, wherein the temperature T1 is 50°C or higher. The method for producing a printed wiring board according to claim 1, wherein the step (II) includes raising the temperature of the resin composition layer to the temperature T2 at a temperature increase rate of 0.5°C/min or more and 30°C/min or less.