JP2018123301A - Thermosetting adhesive sheet and use thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a thermosetting adhesive sheet excellent in the adhesion, heat resistance (particularly after humidification), flexibility, electric insulation, low dielectric constant and low dielectric loss tangent after curing.SOLUTION: The thermosetting adhesive sheet is formed from a thermosetting composition which contains a specific resin (A), a specific curative (B), and an alkali metal compound (D) of 1-110 ppm in terms of the mass of alkali metal elements.SELECTED DRAWING: None

Description

  The present invention relates to a thermosetting adhesive sheet containing a low polarity resin, an organometallic compound, and an epoxy group-containing compound. The thermosetting adhesive sheet of the present invention is suitably used for protecting the circuit surface of a printed wiring board.

In recent years, there has been a remarkable development in the electronics field, and in particular, electronic devices have become smaller, lighter, and higher in density, and electronic materials such as printed wiring boards are increasingly required to be thinner, multilayered, and highly detailed. It has come to be. In the case of a thick rigid substrate typified by conventional glass epoxy or the like, high flexibility, adhesiveness, high electrical insulation, low dielectric constant, and low dielectric loss tangent associated with a narrow space have not been required.
However, recent printed wiring boards and other electronic materials have not only heat resistance and workability, but also high flexibility, adhesion, high electrical insulation due to narrow space, low dielectric constant, and low dielectric loss tangent. It has been demanded.
Specific examples of adhesives and coating agents used around such electronic materials include the following (1) to (6).

(1) Interlayer adhesive: Used to bond circuit boards together, and is in direct contact with copper or silver circuit. It is used between the layers of a multilayer substrate, and there are liquid and sheet-like ones.

(2) Coverlay film adhesive: used to bond a coverlay film (such as a polyimide film used for the purpose of protecting the outermost surface of a circuit) and an underlying circuit board; In many cases, the adhesive layer is integrated.

(3) Adhesive for copper-clad film (CCL): used to bond polyimide film and copper foil together. Processing such as etching is performed when the copper circuit is formed.

(4) Coverlay: used for the purpose of protecting the outermost surface of the circuit, and is formed by printing a printing ink on the circuit or pasting an adhesive sheet and then curing. Some are photosensitive and thermosetting.

(5) Adhesive for reinforcing plate: For the purpose of complementing the mechanical strength of the wiring board, it is used to fix a part of the wiring board to a reinforcing plate made of metal, glass epoxy, polyimide or the like.

(6) Adhesive for electromagnetic wave shield: Affixed to a flexible printed wiring board for the purpose of shielding electromagnetic noise generated from an electronic circuit.

  As these forms, there are liquid forms (ink-printed for printing), sheet-like forms (film-formed in advance), and the like is appropriately selected according to the application.

Various studies have been made in order to meet such high demands on electronic material peripheral members, but no material that sufficiently satisfies all the characteristics has been obtained.
For example, Patent Document 1 discloses an epoxy resin composition mainly composed of a urethane-modified epoxy resin and an epoxy resin curing agent.

  Patent Documents 2 and 3 disclose curable compositions containing a cyanate ester resin and a monovalent phenol compound.

  Patent Document 4 discloses a curable composition comprising a phenol resin obtained by reacting a phenol, a compound having a triazine ring, and a hydroxyl group-substituted aromatic aldehyde and an epoxy resin.

  Patent Document 5 discloses a curable composition for radical polymerization of polyetheresteramide.

  Patent Document 6 discloses an example in which a liquid crystal polymer is used as a method of forming a laminate circuit using a thermoplastic resin having no cross-linked structure.

  Patent Document 7 discloses a curable composition mainly composed of an oxetane structure and a thermal cation curing catalyst.

  Patent Document 8 discloses a tape with an adhesive for TAB having a flexible organic insulating film, an adhesive layer and a protective film, and the adhesive layer comprises a polyamide resin, an organometallic compound, and an epoxy resin. A tape with an adhesive for TAB is disclosed. Specifically, when a copper foil and a polyimide film are bonded together with an adhesive sheet containing a polyamide resin, an organometallic compound, and a bifunctional epoxy resin, the peel strength (adhesive strength) after the plating treatment is It is described that it is excellent and has excellent insulation properties at 150 ° C.

  Patent Document 9 discloses a heat-polymerizable and radiation-polymerizable adhesive sheet containing a polyimide resin (A), an epoxy resin (B), and an epoxy resin curing agent (C).

  Patent Document 10 discloses an optical pressure-sensitive adhesive that further contains an acrylic polymer, an isocyanate curing agent, and an epoxy or metal chelate curing agent.

  Patent Documents 11 and 12 disclose an adhesive film containing an epoxy resin, a curing agent, and a polymer compound that is incompatible with the epoxy resin.

JP 2011-105916 A JP 2001-214053 A JP 2002-138199 A JP 2006-249178 A JP 2013-45755 A JP 2005-105165 A JP 2007-073330 A JP-A-9-64111 JP 2003-41202 A JP 2011-37927 A JP 2008-195943 A JP 2008-112005 A

Although the epoxy resin composition disclosed in Patent Document 1 exhibits adhesiveness derived from urethane and good circuit embedding properties, it has a problem of poor electrical insulation because it contains a large number of highly polar urethane bonds. It was.
Although the curable compositions disclosed in Patent Documents 2 and 3 exhibit good adhesiveness and heat resistance derived from high Tg, there is a problem that a molded product is fragile.
Although the curable composition disclosed in Patent Document 4 exhibits high heat resistance and flame retardancy derived from a high aromatic content, there is a problem that flexibility is inferior due to high intermolecular interaction.
Although the curable composition disclosed in Patent Document 5 exhibits high adhesiveness and insulating properties derived from amides and ethers, it has a problem of poor heat resistance after humidification because it has a structure that easily absorbs moisture.
The laminate circuit forming method disclosed in Patent Document 6 can exhibit high adhesiveness by melting a resin at a high temperature, but since the melting temperature is as high as 280 ° C. or higher, it has an adverse effect on other members having poor heat resistance In addition, there was a problem that it was necessary to introduce equipment corresponding to high temperature melting.
Although the curable composition disclosed in Patent Document 7 exhibits low dielectric constant by suppressing the formation of hydroxyl groups and processing stability derived from low curing shrinkage, which is an advantage of cationic polymerization, it does not cause metal corrosion due to acid generation. There were concerns and problems in stability such as inhibition of curing by moisture.

The tape with an adhesive disclosed in Patent Document 8 has insufficient heat resistance after curing because the epoxy resin used is bifunctional.
Although patent document 9 has provided reflow resistance by the high thermal decomposition resistance derived from a polyimide resin and an epoxy resin, there existed a subject that bending property was inadequate because a crosslinking density became high too much.
The pressure-sensitive adhesive sheet disclosed in Patent Document 10 is used by pasting a sheet after aging, that is, after curing, on a glass plate. Patent Document 10 does not disclose that an adhesive sheet before curing is sandwiched between adherends and thermally cured.
In Patent Documents 11 and 12, by forming a minute phase separation structure with two incompatible components, the thermal stress absorbability is excellent, and an adhesive film with high crack resistance is obtained. There is a problem that the plating solution resistance is insufficient due to an increase in the number of interfaces.

  An object of this invention is to provide the thermosetting adhesive sheet which is excellent in plating solution tolerance after hardening, adhesiveness, heat resistance (especially after humidification), flexibility, and electrical insulation.

In order to solve the above-described problems, the present inventors have intensively studied to use a thermosetting composition containing a resin (A), a curing agent (B), and a specific amount of an alkali metal compound (C). The present invention has been completed.
That is, this invention relates to the thermosetting adhesive sheet formed from the thermosetting composition which satisfy | fills all the following conditions (1)-(5).
(1) A resin (A), a curing agent (B), and an alkali metal compound (C) are included.
(2) The curing agent (B) is at least one selected from the group consisting of an epoxy group-containing compound, an isocyanate group-containing compound, an aziridinyl group-containing compound, and an oxetanyl group-containing compound.
(3) The resin (A) does not have an epoxy group, an isocyanate group, an aziridinyl group, and an oxetanyl group, and has a reactive functional group that can react with the curing agent (B).
(4) The resin (A) is an acrylic resin, a polyester resin, a polyurethane resin, a polyurethane polyurea resin, a polyamide resin, a polyimide resin, a polycarbonate resin, a polyphenylene ether resin, a styrene elastomer, a fluorine resin, and a styrene maleic anhydride resin. Is at least one selected from the group consisting of
(5) The alkali metal compound (C) is contained in an amount of 1 to 110 ppm in terms of the mass of the alkali metal element in the solid content of the thermosetting composition.

The reactive functional group is preferably at least one selected from the group consisting of a carboxyl group, an alcoholic hydroxyl group, a phenolic hydroxyl group, and an acid anhydride group.
The total reactive functional group value of 1 g of the resin (A) is preferably 1 to 80 mg in terms of potassium hydroxide.

  The total of the epoxy group, isocyanate group, aziridinyl group, and oxetanyl group in the curing agent (B) is preferably 0.1 to 12 mol with respect to 1 mol of the reactive functional group of the resin (A).

  In addition, the present invention relates to a thermosetting adhesive sheet with a sheet-like base material, which has the thermosetting adhesive sheet and two sheet-like base materials that cover both surfaces of the thermosetting adhesive sheet.

Furthermore, this invention coats and dries a thermosetting composition satisfying all of the following conditions (1) to (5) on at least one surface of the sheet-like substrate to form a thermosetting adhesive sheet, It is related with the manufacturing method of the thermosetting adhesive sheet with a sheet-like base material which piles up another sheet-like base material on the other side of a curable adhesive sheet.
(1) A resin (A), a curing agent (B), and an alkali metal compound (C) are included.
(2) The curing agent (B) is at least one selected from the group consisting of an epoxy group-containing compound, an isocyanate group-containing compound, an aziridinyl group-containing compound, and an oxetanyl group-containing compound.
(3) The resin (A) does not have an epoxy group, an isocyanate group, an aziridinyl group, and an oxetanyl group, and has a reactive functional group that can react with the curing agent (B).
(4) The resin (A) is an acrylic resin, a polyester resin, a polyurethane resin, a polyurethane polyurea resin, a polyamide resin, a polyimide resin, a polycarbonate resin, a polyphenylene ether resin, a styrene elastomer, a fluorine resin, and a styrene maleic anhydride resin. Is at least one selected from the group consisting of
(5) The alkali metal compound (D) is contained in an amount of 1 to 110 ppm in terms of the mass of the alkali metal element in the solid content of the thermosetting composition.

  Furthermore, this invention relates to the printed wiring board with a protective sheet in which the said circuit surface of the printed wiring board which has an electroconductive circuit is protected by the sheet-like base material through the said sheet-like hardened | cured material.

  Further, the present invention provides a protection in which the thermosetting adhesive sheet is sandwiched between the circuit surface of a printed wiring board having a conductive circuit and a sheet-like substrate, and the thermosetting adhesive sheet is thermoset. The present invention relates to a method for manufacturing a printed wiring board with a sheet.

  The thermosetting adhesive sheet of the present invention is excellent in plating solution resistance after curing, adhesiveness, heat resistance after humidification, flexibility, and electrical insulation.

As described above, the thermosetting adhesive sheet of the present invention includes the resin (A), the curing agent (B), and a specific amount of the alkali metal compound (C).
Hereinafter, the resin (A) will be described in detail.

The resin (A) in the present invention comprises an acrylic resin, a polyester resin, a polyurethane resin, a polyurethane polyurea resin, a polyamide resin, a polyimide resin, a polycarbonate resin, a polyphenylene ether resin, a styrene elastomer, a fluororesin, and a styrene maleic anhydride resin. Selected from the group. A plurality of these may be selected as appropriate. Of these, styrene-based elastomers and polyphenylene ether resins are preferred from the viewpoints of high insulation derived from high hydrophobicity and high heat resistance derived from low thermal decomposition point.

The resin (A) in the present invention does not have an epoxy group, an isocyanate group, an aziridinyl group, and an oxetanyl group, and has a reactive functional group that can react with the curing agent (B).
Examples of the reactive functional group include a carboxyl group, an alcoholic hydroxyl group, a phenolic hydroxyl group, an acid anhydride group and an amino group, a cyanate group, an isocyano group, a cyanato group, an isocyanato group, an imidazole group, a pyrrole group, an acetal group, and an acryloyl group. A methacryloyl group, an aldehyde group, a hydrazide group, a hydrazone group, a phosphoric acid group, etc., and preferably at least one selected from the group consisting of a carboxyl group, an alcoholic hydroxyl group, a phenolic hydroxyl group and an acid anhydride group.
It is preferable that the said reactive functional group can react with a hardening | curing agent (B) at 20-200 degreeC, and it is more preferable that it can react at 140-200 degreeC.

The total reactive functional group value of 1 g of the resin (A) is preferably 1 to 80 mg, more preferably 1 to 50 mg, and further preferably 4 to 30 mg in terms of potassium hydroxide.
Since the reactive functional group contributes to cross-linking formation, the reactive functional group value is preferably 1 mg or more in terms of potassium hydroxide from the viewpoint of heat resistance and insulation of the cured product. Moreover, it is preferable that a reactive functional group value is 80 mg or less in conversion of potassium hydroxide from the point of the adhesiveness of a hardened | cured material, and a flexibility.

The curing agent (B) will be described.
The curing agent (B) is at least one selected from the group consisting of an epoxy group-containing compound, an isocyanate group-containing compound, an aziridinyl group-containing compound, and an oxetanyl group-containing compound. Two or more kinds can be used in combination.

<Epoxy group-containing compound>
One of the curing agents (B), the epoxy group-containing compound is not particularly limited as long as it is a compound having an epoxy group in the molecule, but an average of two or more epoxy groups in one molecule. What has is preferably used. As the epoxy group-containing compound, for example, an epoxy resin such as a glycidyl ether type epoxy resin, a glycidyl amine type epoxy resin, a glycidyl ester type epoxy resin, or a cyclic aliphatic (alicyclic type) epoxy resin can be used.

  Examples of the glycidyl ether type epoxy resin include bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, bisphenol AD type epoxy resin, cresol novolac type epoxy resin, phenol novolac type epoxy resin, α-naphthol novolak. Type epoxy resin, bisphenol A type novolac type epoxy resin, dicyclopentadiene type epoxy resin, tetrabromobisphenol A type epoxy resin, brominated phenol novolac type epoxy resin, tris (glycidyloxyphenyl) methane, or tetrakis (glycidyloxyphenyl) Ethane and the like can be mentioned.

  Examples of the glycidylamine type epoxy resin include tetraglycidyldiaminodiphenylmethane, triglycidylparaaminophenol, triglycidylmetaaminophenol, and tetraglycidylmetaxylylenediamine.

Examples of the glycidyl ester type epoxy resin include diglycidyl phthalate, diglycidyl hexahydrophthalate, diglycidyl tetrahydrophthalate, and the like.
Examples of the cycloaliphatic (alicyclic) epoxy resin include epoxycyclohexylmethyl-epoxycyclohexanecarboxylate, bis (epoxycyclohexyl) adipate, and the like.
As an epoxy group containing compound, the said compound can be used individually by 1 type or in combination of 2 or more types.
Epoxy group-containing compounds include bisphenol A type epoxy resin, cresol novolac type epoxy resin, phenol novolac type epoxy resin, tris (glycidyloxyphenyl) methane, or tetrakis (glycidyloxyphenyl) in terms of high adhesion and heat resistance. It is preferable to use ethane

<Isocyanate group-containing compound>
One of the curing agents (B), the isocyanate group-containing compound, is not particularly limited as long as it is a compound having an isocyanate group in the molecule.
Specific examples of the isocyanate group-containing compound having one isocyanate group in one molecule include n-butyl isocyanate, isopropyl isocyanate, phenyl isocyanate, benzyl isocyanate, (meth) acryloyloxyethyl isocyanate, 1,1-bis [ (Meth) acryloyloxymethyl] ethyl isocyanate, vinyl isocyanate, allyl isocyanate, (meth) acryloyl isocyanate, isopropenyl-α, α-dimethylbenzyl isocyanate and the like.
In addition, 1,6-diisocyanatohexane, isophorone diisocyanate, 4,4′-diphenylmethane diisocyanate, polymeric diphenylmethane diisocyanate, xylylene diisocyanate, tolylene 2,4-diisocyanate, toluene diisocyanate, 2,4-diisocyanic acid Toluene, hexamethylene diisocyanate, 4-methyl-m-phenylene diisocyanate, naphthylene diisocyanate, paraphenylene diisocyanate, tetramethylxylylene diisocyanate, cyclohexylmethane diisocyanate, hydrogenated xylylene diisocyanate, cyclohexyl diisocyanate, tolidine diisocyanate, 2,2 , 4-Trimethylhexamethylene diisocyanate, 2,4,4-trimethylhexamethylene diisocyanate Nitrate, m-tetramethylxylylene diisocyanate, P-tetramethylxylylene diisocyanate, diisocyanate ester compounds such as dimer acid diisocyanate and hydroxyl group, carboxyl group, and amide group-containing vinyl monomers are reacted in equimolar amounts. It can be used as an ester compound.

Specific examples of the isocyanate group-containing compound having two isocyanate groups in one molecule include 1,3-phenylene diisocyanate, 4,4′-diphenyl diisocyanate, 1,4-phenylene diisocyanate, and 4,4′-diphenylmethane. Diisocyanate, 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, 4,4′-toluidine diisocyanate, 2,4,6-triisocyanate toluene, 1,3,5-triisocyanate benzene, dianisidine diisocyanate, Aromatic diisocyanates such as 4,4′-diphenyl ether diisocyanate, 4,4 ′, 4 ″ -triphenylmethane triisocyanate,
Trimethylene diisocyanate, tetramethylene diisocyanate, hexamethylene diisocyanate, pentamethylene diisocyanate, 1,2-propylene diisocyanate, 2,3-butylene diisocyanate, 1,3-butylene diisocyanate, dodecamethylene diisocyanate, 2,4,4-trimethylhexamethylene Aliphatic diisocyanates such as diisocyanates,
ω, ω′-diisocyanate-1,3-dimethylbenzene, ω, ω′-diisocyanate-1,4-dimethylbenzene, ω, ω′-diisocyanate-1,4-diethylbenzene, 1,4-tetramethylxylylene diisocyanate Araliphatic diisocyanates such as 1,3-tetramethylxylylene diisocyanate,
3-isocyanate methyl-3,5,5-trimethylcyclohexyl isocyanate [
Also known as: isophorone diisocyanate], 1,3-cyclopentane diisocyanate, 1,3-cyclohexane diisocyanate, 1,4-cyclohexane diisocyanate, methyl-2,4-cyclohexane diisocyanate, methyl-2,6-cyclohexane diisocyanate, 4,4 ′ -Alicyclic diisocyanates such as methylene bis (cyclohexyl isocyanate), 1,3-bis (isocyanate methyl) cyclohexane, 1,4-bis (isocyanate methyl) cyclohexane.

  Specific examples of the isocyanate group-containing compound having three isocyanate groups in one molecule include aliphatic polyisocyanates such as aromatic polyisocyanates and lysine triisocyanates, araliphatic polyisocyanates, and alicyclic polyisocyanates. And the like, and the trimethylolpropane adduct of diisocyanate described above, a burette reacted with water, and a trimer having an isocyanurate ring.

As the isocyanate group-containing compound, a blocked isocyanate group-containing compound in which the isocyanate group in various exemplified isocyanate group-containing compounds is protected with ε-caprolactam, MEK oxime, or the like can also be used.
Specific examples include those obtained by blocking the isocyanate group of the isocyanate group-containing compound with ε-caprolactam, methyl ethyl ketone (hereinafter referred to as MEK) oxime, cyclohexanone oxime, pyrazole, phenol, and the like. In particular, a hexamethylene diisocyanate trimer having an isocyanurate ring and blocked with MEK oxime or pyrazole is very preferable because it has excellent adhesion strength and heat resistance to polyimide and copper.

<Aziridinyl group-containing compound>
One of the curing agents (B), the aziridine group-containing compound, is not particularly limited as long as it is a compound containing an aziridine group in the molecule.
Examples of the aziridine group-containing compound include N, N′-diphenylmethane-4,4′-bis (1-aziridinecarboxite), N, N′-toluene-2,4-bis (1-aziridinecarboxite), Bisisophthaloyl-1- (2-methylaziridine), tri-1-aziridinylphosphine oxide, N, N′-hexamethylene-1,6-bis (1-aziridinecarboxite), trimethylolpropane-tri -Β-aziridinylpropionate, tetramethylolmethane-tri-β-aziridinylpropionate, tris-2,4,6- (1-aziridinyl) -1,3,5-triazine, trimethylolpropane Tris [3- (1-aziridinyl) propionate], trimethylolpropane tris [3- (1-aziridinyl) butyrate ], Trimethylolpropane tris [3- (1- (2-methyl) aziridinyl) propionate], trimethylolpropane tris [3- (1-aziridinyl) -2-methylpropionate], 2,2′-bishydroxy Methylbutanol tris [3- (1-aziridinyl) propionate], pentaerythritol tetra [3- (1-aziridinyl) propionate], diphenylmethane-4,4-bis-N, N′-ethyleneurea, 1,6-hexamethylene Bis-N, N′-ethylene urea, 2,4,6- (triethyleneimino) -Syn-triazine, bis [1- (2-ethyl) aziridinyl] benzene-1,3-carboxylic acid amide and the like can be mentioned. .

  In particular, 2,2′-bishydroxymethylbutanol tris [3- (1-aziridinyl) propionate], when used in the present invention, can suppress protrusion during hot pressing and retain the flexibility of the cured coating film. Since heat resistance can be improved as it is, it is preferably used in the present invention.

<Oxetanyl group-containing compound>]
As one of the curing agents (B), an oxetanyl group-containing compound, for example, 1,4-bis {[
(3-ethyloxetane-3-yl) methoxy] methyl} benzene, 3-ethyl-3-{[(3-ethyloxetane-3-yl) methoxy] methyl} oxetane, 1,3-bis [(3-ethyl Oxetane-3-yl) methoxy] benzene, 4,4′-bis [(3-ethyl-3-oxetanyl) methoxymethyl] biphenyl, esterified product of (2-ethyl-2-oxetanyl) ethanol and terephthalic acid, ( Examples include etherified products of 2-ethyl-2-oxetanyl) ethanol and phenol novolac resins, esterified products of (2-ethyl-2-oxetanyl) ethanol and polyvalent carboxylic acid compounds, and the like.

  The curing agent (B) used in the present invention has a total of 0.1 to 12 mol of an epoxy group, an isocyanate group, an aziridinyl group, and an oxetanyl group with respect to 1 mol of the reactive functional group in the resin (A). It is preferable to contain in the range which becomes, It is more preferable to contain 0.3-10 mol, It is more preferable to contain 0.5-5 molmol. By setting the epoxy group or the like in the curing agent (B) to 0.1 mol or more with respect to the reactive functional group of the resin (A), the crosslink density can be increased, and the heat resistance, insulation, and adhesiveness can be improved. By setting the epoxy group or the like to 20 mol or less, flexibility and electrical insulation can be improved.

<Alkali metal compound (C)>
The thermosetting adhesive sheet of the present invention contains 1-110 ppm of an alkali metal compound (C) in terms of the mass of an alkali metal element in terms of resistance to plating solution after curing. When the content of the alkali metal compound (C) in terms of the mass of the alkali metal element is 1 ppm or more, plating solution resistance can be imparted. The reason for this is not clear, but it is considered that an alkali metal having a high ionization tendency promotes ionization during immersion of the plating solution, and the generated ions and the reactive functional group of the resin form a strong metal bridge.
Moreover, insulation can be ensured because the content rate of the alkali metal compound (C) in terms of mass of the alkali metal element is 110 ppm or less. If the content is 110 ppm or more, the electrical insulation properties deteriorate. The content of the alkali metal compound (C) in terms of mass of the alkali metal element is preferably 10 to 90 ppm, and more preferably 30 to 70 ppm.

The alkali metal compound (C) contained in the thermosetting adhesive sheet of the present invention may be contained in the resin (A), the curing agent (B), other curing agents described later, and various additives. , Resin (A), curing agent (B) and the like may be blended separately. In the case of a resin (A) or a curing agent (B) containing a large amount of alkali metal compound (C), the amount of alkali metal compound (C) can be reduced by washing.
In addition, when an alkali metal compound (C) is contained in resin (A), a hardening | curing agent (B), the other hardening | curing agent mentioned later, and various additives, an alkali metal compound (C) is each manufacturing process. It may be a catalyst used or a decomposition product thereof, or a catalyst mixed in the process.

The element conversion content X (ppm) of the alkali metal compound (C) contained in 1 g of the thermosetting composition (thermosetting adhesive sheet) can be determined as follows.
Content of alkali metal compound (C): Y (g),
Molecular weight of alkali metal compound (C): A,
Amount of alkali metal element in the alkali metal compound (C): B = X = [Y × (B / A)] × 10 ⁶
For example, in the case of lithium carbonate (Li ₂ CO ₃ )
Molecular weight A is 73.89,
The amount B of alkali metal contained is (6.94 × 2),
When 0.0001 g of lithium carbonate is contained in 1 g of the thermosetting composition (thermosetting adhesive sheet),
X = [0.0001 × ((6.94 × 2) /73.89)] × 10 ⁶
= 18.8.

The type and amount of the alkali metal compound (C) contained in each raw material contained in the thermosetting composition (thermosetting adhesive sheet) are determined, and the total content of the alkali metal compound (C) is obtained. : Y (g) can be obtained and the element-conversion content X (ppm) can be obtained, but the element-conversion content X (ppm) can also be obtained as follows.
That is, a thermosetting composition (thermosetting adhesive sheet) having an arbitrary mass is decomposed by the following method, and the obtained decomposition solution is contained by ICP emission spectroscopic analysis (hereinafter referred to as ICP analysis). The element conversion content X of an alkali metal compound (C) can be calculated | required.
In addition, when both of the same kind of alkali metal compounds are included, for example, when lithium carbonate and lithium acetoacetate are included, according to the ICP analysis method, the lithium element equivalent content is obtained.

  Specifically, a weighed sample is thermally decomposed with nitric acid, diluted to a constant volume, measured with an ICP analyzer, and quantified with a calibration curve prepared with a standard solution of the target element.

  Specific examples of the alkali metal compound (D) include alkali metal hydroxides, alkali metal carbonates, alkali metal hydrogen carbonates, alkali metal carboxylates, alkyl alkali metals, and the like. It is not limited.

  Examples of the alkali metal hydroxide include lithium hydroxide, sodium hydroxide, potassium hydroxide, rubidium hydroxide, and cesium hydroxide.

  Examples of the alkali metal carbonate include sodium carbonate, sodium bicarbonate, potassium carbonate, potassium bicarbonate, lithium carbonate and the like, and hydrates thereof.

  Examples of the alkali metal hydrogen carbonate include sodium hydrogen carbonate and calcium hydrogen carbonate, and hydrates thereof.

As an alkali metal carboxylate, a C1-C10 carboxylate is preferable, and a C1-C3 carboxylate is more preferable.
Specific examples of the carboxylic acid include linear saturated fatty acids such as formic acid, acetic acid, propionic acid, butyric acid, valeric acid, caproic acid, enanthic acid, capric acid, pelargonic acid; oxalic acid, fumaric acid, maleic acid, succinic acid Aliphatic dicarboxylic acids such as acid, glutaric acid, adipic acid, pimelic acid, suberic acid, and azelaic acid; hydroxy such as glycolic acid, lactic acid, hydroxybutyric acid, tartaric acid, malic acid, and mevalonic acid; benzoic acid, terephthalic acid, isophthalic acid And aromatic carboxylic acids such as orthophthalic acid, and hydrates thereof.
Among these, alkali metal hydroxides, alkali metal acetates, and alkali metal carbonates are preferable. Among them, alkali metal hydroxides are easily ionized.

  Examples of the alkyl alkali metal include methyl lithium, i-propyl lithium, sec-butyl lithium, n-butyl lithium, t-butyl lithium, and n-dodecyl lithium.

  Other examples include phenyl lithium, α- and β-naphthyl lithium, styryl lithium, benzyl lithium and the like.

  The alkali metal is an element belonging to Group 1 in the periodic table, and specific examples include sodium, potassium, lithium, rubidium, cesium and the like.

In addition to the resin (A), the curing agent (B), and the alkali metal compound (C), the thermosetting composition (thermosetting adhesive sheet) of the present invention has other curing agents as long as the physical properties are not impaired. Can be included.
Specific examples of the other curing agent include carbodiimide group-containing compounds, benzoxazine compounds, β-hydroxyalkylamide group-containing compounds, sulfur-containing compounds and the like, but are not particularly limited.

[Carbodiimide group-containing compound]
As one of the other curing agents, a carbodiimide group-containing compound, there is a carbodilite series manufactured by Nisshinbo Industries, Ltd. Among these, Carbodilite V-01, 03, 05, 07, and 09 are preferable because of excellent compatibility with organic solvents. When used in the present invention, an improvement in adhesiveness can be expected, so that it is preferably used.

[Benzoxazine compounds]
As one of the other curing agents, benzoxazine compounds include “P-a”, “P-alP”, “P-ala”, “B-ala”, Macromolecules, described in Macromolecules, 36, 6010 (2003). 34, 7257 (2001), “P-appe”, “B-appe”, “Ba-type benzoxazine”, “Fa-type benzoxazine”, “Bm-type benzoxazine” manufactured by Shikoku Kasei Co., Ltd. Or the like.

[β-Hydroxyalkylamide group-containing compound]
As one of the other curing agents, the β-hydroxyalkylamide group-containing compound includes, for example, N, N, N ′, N′-tetrakis (hydroxyethyl) adipamide (Primid XL-552 manufactured by Ems Chemie). Various compounds can be mentioned.

[Sulfur-containing compounds]
One of the other curing agents, sulfur-containing compounds, includes thiol compounds, sulfide compounds, and polysulfide compounds. When used in the present invention, it can be suitably used because it can be expected to improve adhesion and heat resistance.

[Thiol compound]
The thiol compound contains, for example, at least a thiol group and a linear, branched, or cyclic hydrocarbon group. Two or more thiol groups may be contained. The hydrocarbon group may be saturated or unsaturated. Some of the hydrogen atoms of the hydrocarbon group may be substituted with a hydroxyl group, amino group, carboxyl group, halogen atom, alkoxysilyl group, or the like. More specifically, examples of colorless thiols include 1-propanethiol, 3-mercaptopropionic acid, (3-mercaptopropyl) trimethoxysilane, 1-butanethiol, 2-butanethiol, isobutylmercaptan, isoamyl. Mercaptan, cyclopentanethiol, 1-hexanethiol, cyclohexanethiol, 6-hydroxy-1-hexanethiol, 6-amino-1-hexanethiol hydrochloride, 1-heptanethiol, 7-carboxy-1-heptanethiol, 7- Amido-1-heptanethiol, 1-octanethiol, tert-octanethiol, 8-hydroxy-1-octanethiol, 8-amino-1-octanethiol hydrochloride, 1H, 1H, 2H, 2H-perfluorooctanethiol, 1-nonanethiol, 1-decanethiol, 10-carboxy-1-decanethiol, 10-amido-1-decanethiol, 1- Phthalene thiol, 2-naphthalene thiol, 1-undecane thiol, 11-amino-1-undecane thiol hydrochloride, 11-hydroxy-1-undecane thiol, 1-dodecane thiol, 1-tetradecane thiol, 1-hexadecane thiol, 16 -Hydroxy-1-hexadecanethiol, 16-amino-1-hexadecanethiol hydrochloride, 1-octadecanethiol, 1,4-butanedithiol, 2,3-butanedithiol, 1,6-hexanedithiol, 1,2-benzene Examples include dithiol, 1,9-nonanedithiol, 1,10-decanedithiol, 1,3,5-benzenetrithiol, 3-mercaptopropylmethyldimethoxysilane, and 3-mercaptopropyltrimethoxysilane. These thiols can be used alone or in combination of two or more.

[Sulphide compounds]
The sulfide compound contains, for example, at least a sulfide group and a linear, branched, or cyclic hydrocarbon group. Two or more sulfide groups may be contained. Some of the hydrogen atoms of the hydrocarbon group may be substituted with a hydroxyl group, amino group, carboxyl group, halogen atom, alkoxysilyl group, or the like.
More specifically, as the sulfide compound, for example, propyl sulfide, furfuryl sulfide, hexyl sulfide, phenyl sulfide, phenyl trifluoromethyl sulfide, bis (4-hydroxyphenyl) sulfide, heptyl sulfide, octyl sulfide, nonyl sulfide, decyl Examples thereof include sulfide, dodecylmethyl sulfide, dodecyl sulfide, tetradecyl sulfide, hexadecyl sulfide, octadecyl sulfide, bis (triethoxysilylpropyl) tetrasulfide and the like. These sulfides can be used alone or in combination of two or more.

[Polysulfide compound]
Examples of the polysulfide compound include 2-hydroxyethyl disulfide, propyl disulfide, isopropyl disulfide, 3-carboxypropyl disulfide, allyl disulfide, isobutyl disulfide, tert-butyl disulfide, amyl disulfide, isoamyl disulfide, 5-carboxypentyl disulfide, furfuryl. Disulfide, hexyl disulfide, cyclohexyl disulfide, phenyl disulfide, 4-aminophenyl disulfide, heptyl disulfide, 7-carboxyheptyl disulfide, benzyl disulfide, tert-octyl disulfide, decyl disulfide, 10-carboxydecyl disulfide, hexadecyl disulfide, thiuram disulfide, etc. Can be used.

In the present invention, the amount of other curing agent used is not particularly limited, but is preferably 0.01 to 20 mol per 1 mol of the reactive functional group of the resin (A). It is more preferable to contain 5-10 mol, and it is more preferable to contain 0.1-5 mol.
Or it is preferable to contain 0.01-20 mol with respect to 1 mol of epoxy groups etc. in a hardening | curing agent (B), It is more preferable to contain 0.5-10 mol, It is further containing 0.1-5 mol preferable.

<Filler>
Next, the filler that can be used in the present invention will be described in detail.
The thermosetting adhesive sheet of the present invention can contain a filler for the purpose of imparting flame retardancy, controlling the fluidity of the adhesive, and improving the elastic modulus of the cured product.

Although it does not specifically limit as a filler, As a shape, spherical shape, powder shape, fibrous shape, needle shape, scale shape, etc. are mentioned.
Examples of fillers include polytetrafluoroethylene powder, polyethylene powder, polyacrylic acid ester powder, epoxy resin powder, polyamide powder, polyurethane powder, polysiloxane powder, silicone, acrylic, styrene butadiene rubber, butadiene rubber, etc. Polymer filler such as core shell of multilayer structure used;
(Poly) phosphates such as melamine phosphate, melamine polyphosphate, guanidine phosphate, guanidine polyphosphate, ammonium phosphate, ammonium polyphosphate, ammonium amidophosphate, ammonium amidophosphate, carbamate phosphate, carbamate polyphosphate Compounds, organophosphate ester compounds, phosphazene compounds, phosphonic acid compounds, diethyl diethylphosphinate, aluminum methylethylphosphinate, aluminum diphenylphosphinate, aluminum ethylbutylphosphinate, aluminum methylbutylphosphinate, aluminum polyethylenephosphinate, etc. Phosphorus flame retardant fillers such as acid compounds, phosphine oxide compounds, phosphorane compounds, phosphoramide compounds;
Nitrogen-based flame retardant fillers such as benzoguanamine, melamine, melam, melem, melon, melamine cyanurate, cyanuric acid compound, isocyanuric acid compound, triazole compound, tetrazole compound, diazo compound, urea;
Silica, mica, talc, kaolin, clay, hydrotalcite, wollastonite, zonotlite, silicon nitride, boron nitride, aluminum nitride, calcium hydrogen phosphate, calcium phosphate, glass flakes, hydrated glass, calcium titanate, sepiolite, sulfuric acid Magnesium, aluminum hydroxide, magnesium hydroxide, zirconium hydroxide, barium hydroxide, calcium hydroxide, titanium oxide, tin oxide, aluminum oxide, magnesium oxide, zirconium oxide, zinc oxide, molybdenum oxide, antimony oxide, nickel oxide, carbonic acid Examples include inorganic fillers such as zinc, magnesium carbonate, calcium carbonate, barium carbonate, zinc borate, and aluminum borate.

  Among them, it is desirable to use a non-halogen flame retardant such as a phosphorus flame retardant filler or a nitrogen flame retardant filler, which has been recently taken into consideration as the filler, and in particular, the adhesive of the present invention. It is preferable to use a phosphazene compound, a phosphine compound, a melamine polyphosphate, an ammonium polyphosphate, a melamine cyanurate, or the like that is more effective in flame retardancy when used in combination with the composition. In addition, it is preferable to use polytetrafluoroethylene powder from the viewpoint of further reducing the dielectric constant and dielectric loss tangent, and it has excellent balance not only with dielectric properties but also with adhesion, flexibility, electrical insulation and heat resistance. You can get things. In the present invention, these fillers can be used alone or in combination.

  The average particle diameter D50 of these fillers is preferably 0.1 μm to 25 μm. When a filler having an average particle diameter close to 0.1 μm is used, a modification effect by the filler is easily obtained, and further, dispersibility and stability of the dispersion liquid are easily improved. Moreover, when the filler which shows the average particle diameter near 25 micrometers is used, the mechanical characteristic of a cured film becomes easy to improve.

  As an addition amount of a filler, it is preferable that it is 0.01-500 mass parts with respect to 100 mass parts of said resin (A). If the amount of filler added is below this range, the modification effect by the filler is difficult to obtain, and if it exceeds this range, the mechanical properties of the cured film may be greatly impaired.

  The method for adding the filler is not particularly limited, and any conventionally known method may be used. Specifically, a method of adding to the polymerization reaction solution before or during the polymerization, using a three roll, etc. Examples thereof include a method of kneading the filler and a method of preparing a dispersion containing the filler and mixing it. Further, in order to disperse the filler satisfactorily and stabilize the dispersion state, a dispersant, a thickener and the like can be used as long as the physical properties of the adhesive sheet are not affected.

<Other additives>
In addition, the thermosetting adhesive sheet of the present invention may further include dyes, pigments, antioxidants, polymerization inhibitors, antifoaming agents, leveling agents, ion scavengers, moisturizing agents as optional components as long as the purpose is not impaired. An agent, a viscosity modifier, an antiseptic, an antibacterial agent, an antistatic agent, an antiblocking agent, an ultraviolet absorber, an infrared absorber, an electromagnetic wave shielding agent, and the like can be added.

[Thermosetting adhesive sheet with sheet-like substrate]
The thermosetting adhesive sheet with a sheet-like substrate of the present invention can be obtained, for example, as follows.
After applying the thermosetting adhesive in a solution or dispersion state to at least one side of the sheet-like substrate, it is usually dried at 40 to 150 ° C., thereby forming a sheet-like base on the so-called B-stage thermosetting adhesive sheet. You can get the one with the material. Next, the other surface of the thermosetting adhesive sheet is covered with another sheet-like base material, whereby the thermosetting adhesive sheet with the sheet-like base material of the present invention can be obtained.
At least one of the sheet-like substrates to be used is preferably a peelable sheet-like substrate. That is, a thermosetting adhesive in a solution or dispersion state is applied to a peelable sheet-like substrate and dried to form a thermosetting adhesive sheet, and the other surface of the thermosetting adhesive sheet is then placed on the other side. It can also be covered with a peelable sheet-like base material, or can be covered with a non-peelable sheet-like base material to be an adherend. Alternatively, a thermosetting adhesive in a solution or dispersion state is applied to a non-peelable sheet-like substrate to be an adherend and dried to form a thermosetting adhesive sheet, and then the thermosetting adhesive sheet The other surface can be covered with another peelable sheet-like substrate.

The dry film thickness of the thermosetting adhesive sheet is preferably 5 to 500 μm, more preferably 10 to 100 μm, from the viewpoint of easy handling and sufficient adhesiveness and solder heat resistance.
Examples of the coating method include comma coating, knife coating, die coating, lip coating, roll coating, curtain coating, bar coating, gravure printing, flexographic printing, dip coating, spray coating, and spin coating.

Examples of the non-peelable sheet-like substrate used include various plastic films, such as polyimide films, polyester films, polyphenylene ether films, polyphenylene sulfide films, polystyrene films, polycarbonate films, polyether ether ketone films. Is mentioned.
Examples of the sheet-like base material that can be peeled include those obtained by subjecting various plastic films to release treatment and those obtained by subjecting paper to release treatment. Examples of the various plastic films to be subjected to the peeling treatment include polyester films and polyolefin films.

[Cured sheet], [Printed wiring board with protective sheet]
The sheet-like cured product of the present invention is obtained by thermosetting the thermosetting adhesive sheet of the present invention, for example, at a temperature of about 40 to 200 ° C.

Use a thermosetting adhesive sheet with a sheet-like substrate in which one side of the thermosetting adhesive sheet is covered with a peelable sheet-like substrate and the other surface is covered with an adherend (for example, a polyimide film or a polyester film). The case will be described.
The peelable sheet-like substrate is peeled off from the thermosetting adhesive sheet with the sheet-like substrate. Another adherend (for example, the circuit surface side of the printed wiring board having a conductive circuit) is overlaid on the exposed thermosetting adhesive sheet. Next, the thermosetting adhesive sheet sandwiched between both adherends is thermoset by heating and pressurizing.
If it does in this way, the printed circuit board with a protection sheet which the said circuit surface of the printed wiring board which has an electroconductive circuit protected by a sheet-like base material can be obtained through a sheet-like hardened | cured material.

Next, the case where the thermosetting adhesive sheet with a sheet-like base material in which two peelable sheet-like base materials respectively cover both surfaces of the thermosetting adhesive sheet is described.
One peelable sheet-like substrate is peeled off from the thermosetting adhesive sheet with the sheet-like substrate. An adherend (for example, polyimide film or polyester film) on the exposed thermosetting adhesive sheet
Repeat. The other peelable sheet-like substrate that has covered the other surface of the thermosetting adhesive sheet is peeled off. Another adherend (for example, the circuit surface side of the printed wiring board having a conductive circuit) is overlaid on the exposed thermosetting adhesive sheet. Next, the thermosetting adhesive sheet sandwiched between both adherends is thermoset by heating and pressurizing. The circuit surface side of the printed wiring board having a conductive circuit can be overlaid on the surface from which the peelable sheet-like substrate is first peeled off, and a polyimide film or a polyester film can be overlaid on the other surface of the thermosetting adhesive sheet. .

Examples of the printed wiring board having a conductive circuit include a flexible printed wiring board in which a conductive circuit is formed on a plastic film having flexibility and insulation such as polyester and polyimide.
As a method for providing a conductive circuit, for example, a photosensitive etching resist layer is formed on a copper foil of a flexible copper-clad plate in which a copper foil is provided on a base film with or without an adhesive layer. Expose the conductive circuit from the copper foil by exposing it through a mask film with a pattern, curing only the exposed area, then removing the unexposed area of the copper foil by etching, and then peeling off the remaining resist layer. Can be formed.
Or the method of providing only a required circuit by means, such as sputtering and plating, on a base film is also mentioned.
Or the method of forming an electroconductive circuit on a base film by a printing technique using the electroconductive ink containing the particle | grains of silver and copper is also mentioned.

The thermosetting adhesive sheet of the present invention is suitably used for producing a printed wiring board with a protective sheet, and can also be used as follows.
<Multi-layering of multiple flexible printed wiring>
By sandwiching the thermosetting adhesive sheet of the present invention between a plurality of flexible printed wirings and heating and pressing, the thermosetting adhesive sheet can be cured to obtain a multilayer flexible printed wiring board.
<Lamination of base film for flexible printed wiring board and copper foil>
For example, the thermosetting adhesive sheet can be cured by sandwiching the thermosetting adhesive sheet of the present invention between a polyimide film and a copper foil, and heating and pressing.

  The present invention will be described more specifically with reference to the following examples. However, the following examples do not limit the scope of rights of the present invention. In the examples, “parts” and “%” represent “parts by weight” and “% by weight”, respectively, and Mw represents a mass average molecular weight.

<Measuring method of hydroxyl value (phenolic and alcoholic)>
The phenolic and alcoholic hydroxyl value is the amount of potassium hydroxide required to neutralize acetic acid bonded to a hydroxyl group when the hydroxyl group is acetylated by the amount of hydroxyl group contained in 1 g of resin solids (mg ).
The hydroxyl value is measured according to JIS K0070, and is calculated in consideration of the acid value as shown in the following formula.

About 1 g of a sample is accurately weighed in a stoppered Erlenmeyer flask and dissolved by adding 100 ml of cyclohexanone solvent. Further, exactly 5 ml of an acetylating agent (a solution in which 25 g of acetic anhydride was dissolved in pyridine to make a volume of 100 ml) was added and stirred for about 1 hour. To this, phenolphthalein reagent is added as an indicator and lasts for 30 seconds. Thereafter, the solution is titrated with a 0.5N alcoholic potassium hydroxide solution until the solution becomes light red.
The hydroxyl value was determined by the following formula (unit: mgKOH / g).
Hydroxyl value (mgKOH / g) = [{(ba) × F × 28.05} / S] + D
However,
S: Sample collection amount (g)
a: Consumption of 0.5N alcoholic potassium hydroxide solution (ml)
b: Consumption of the 0.5N alcoholic potassium hydroxide solution in the blank experiment (ml)
F: Potency of 0.5N alcoholic potassium hydroxide solution D: Acid value (mgKOH / g)
<Measurement of acid value>
About 1 g of a sample is accurately weighed in a stoppered Erlenmeyer flask and dissolved by adding 100 ml of cyclohexanone solvent. To this is added phenolphthalein reagent as an indicator and held for 30 seconds. Thereafter, the solution is titrated with a 0.1N alcoholic potassium hydroxide solution until the solution becomes light red. The acid value was determined by the following formula (unit: mgKOH / g).
Acid value (mgKOH / g) = (5.611 × a × F) / S
However,
S: Sample collection amount (g)
a: Consumption of 0.1N alcoholic potassium hydroxide solution (ml)
F: Potency of 0.1N alcoholic potassium hydroxide solution

<Method for measuring acid anhydride value>
About 1 g of a sample was accurately weighed in a stoppered Erlenmeyer flask and dissolved by adding 100 ml of 1,4-dioxane solvent. 10 mL of a mixed solution of octylamine, 1,4-dioxane and water (weight mixing ratio: 1.49 / 800/80) was added thereto, and the mixture was stirred for 15 minutes to complete the reaction.
Thereafter, excess octylamine was titrated with a mixed solution of 0.02M perchloric acid and 1,4-dioxane. Moreover, the measurement was carried out using 10 mL of a mixed solution of octylamine, 1,4-dioxane, and water (weight mixing ratio: 1.49 / 800/80), to which no sample was added, as a blank. The acid anhydride value was determined by the following formula (unit: mgKOH / g).
Acid anhydride value (mgKOH / g) = 0.02 × (B−S) × F × 56.11 / W
B: Blank titration (mL)
S: Sample titration (mL)
W: Sample solid content (g)
F: 0.02 mol / L perchloric acid titer

<Measurement method of mass average molecular weight (Mw)>
For measurement of Mw, GPC (gel permeation chromatography) “HPC-8020” manufactured by Tosoh Corporation was used. GPC is liquid chromatography that separates and quantifies substances dissolved in a solvent (THF; tetrahydrofuran) based on the difference in molecular size. For the measurement in the present invention, two columns “LF-604” (manufactured by Showa Denko KK: GPC column for rapid analysis: 6 mm ID × 150 mm size) are connected in series, and the flow rate is 0.6 ml / m.
in, the column temperature was 40 ° C., and the weight average molecular weight (Mw) was determined in terms of polystyrene.

[Synthesis Example 1]
<Synthesis example of acrylic resin>
In a four-necked flask equipped with a stirrer, reflux condenser, nitrogen inlet pipe, inlet pipe, thermometer, 300 g of methyl ethyl ketone (hereinafter referred to as MEK) is heated to 80 ° C. while injecting nitrogen gas into the container. At the same temperature, 30 g of butyl methacrylate, 28 g of methyl methacrylate, 3 g of 1: 1 (mass ratio) mixture of lauryl methacrylate and tridecyl methacrylate, 12 g of methacrylic acid, 2,2′-azobisisobutyronitrile 8 g of the mixture was added dropwise over 1 hour to conduct a polymerization reaction. After the completion of the dropwise addition, the mixture was further reacted at 80 ° C. for 3 hours, then 1.2 parts of 2,2′-azobisisobutyronitrile dissolved in 50 g of MEK was added, and the mixture was reacted at 80 ° C. for 1 hour. An acrylic resin solution was obtained. The mass average molecular weight was 52,000, and the acid value was 78.2 mgKOH / g.

[Synthesis Examples 2-3]
Synthesis was performed according to the composition shown in Table 1 in the same manner as in Synthesis Example 1 to obtain an acrylic resin.

[Synthesis Example 4]
<Examples of polyester resin synthesis>
In a four-necked flask equipped with a stirrer, reflux condenser, nitrogen inlet tube, inlet tube and thermometer, 57.6 g of sebacic acid, 3.2 g of trimesic acid, 27.5 g of cyclohexanedimethanol, 1.6-hexane Diol 9.7 g and tetrabutyl titanate 0.012 g were charged and stirred until the temperature of the exotherm became constant. When the temperature is stabilized, the temperature is raised to 110 ° C. After confirming that the temperature has stabilized, the temperature is raised to 120 ° C. after 30 minutes, and then the dehydration reaction is performed while raising the temperature by 10 ° C. every 30 minutes. Continued. When the temperature reached 230 ° C., the reaction was continued for 3 hours at the same temperature, and held for 1 hour under a vacuum of about 2 KPa. Thereafter, the temperature was lowered to obtain a polyester resin. The mass average molecular weight was 32,000, and the acid value was 39.8 mgKOH / g.

[Synthesis Examples 5 to 10]
Synthesis was performed in the same manner as in Synthesis Example 4 according to the composition shown in Table 2 to obtain a polyester resin.

[Synthesis Example 11]
<Synthesis example of polyurethane resin>
In a four-necked flask equipped with a stirrer, reflux condenser, nitrogen inlet tube, inlet tube, thermometer, 1.6-hexanediol 10.6 g, C36 dimer diol (PRIPOL 2033: CRODA JAPAN, OH value = 207 mgKOH / g) 113.3 g, 44.3 g of tolylene diisocyanate, and 240 g of toluene as a solvent were charged, and the mixture was heated to 60 ° C. with stirring in a nitrogen stream and dissolved uniformly. Subsequently, 0.016 g of dibutyltin dilaurate was added to the flask as a catalyst, and the mixture was stirred at 100 ° C. for 3 hours to carry out a urethanization reaction. Next, 40 g of toluene and 17.6 g of trimellitic anhydride were added, stirred at 90 ° C. for 1 hour, then heated to 135 ° C. and reacted for 4 hours. Cooling to room temperature gave a polyurethane resin. The mass average molecular weight was 11,000, and the acid value was 55.3 mgKOH / g.

[Synthesis Example 12]
Synthesis was performed according to the composition shown in Table 3 in the same manner as in Synthesis Example 11 to obtain a polyurethane resin.

[Synthesis Example 13]
<Synthesis example of polyurethane urea resin>
In a four-necked flask equipped with a stirrer, reflux condenser, nitrogen inlet tube, inlet tube and thermometer, 28.4 g of 1.6-hexanediol, 8.9 g of dimethylolbutanoic acid, 55.6 g of tolylene diisocyanate, solvent As a solution, 122 g of toluene was charged and stirred at 60 ° C. under a nitrogen stream.
The solution was heated up to be dissolved uniformly. Subsequently, 0.008 g of dibutyltin dilaurate was added to the flask as a catalyst and stirred at 100 ° C. for 3 hours to carry out a urethanization reaction. Next, the temperature was lowered to 80 ° C. and 1.9 g of hexylamine dissolved in 20 g of toluene was dropped over 30 minutes, and then stirred at 100 ° C. for 6 hours. After cooling to room temperature, a polyurethaneurea resin was obtained. The mass average molecular weight was 14,000, and the acid value was 34.8 mgKOH / g.

[Synthesis Example 14]
<Synthesis example of polyurethane urea resin>
Synthesis was performed according to the composition shown in Table 4 in the same manner as in Synthesis Example 13 to obtain a polyurethaneurea resin.

[Synthesis Example 15]
<Synthesis example of polyamide resin>
In a four-necked flask equipped with a stirrer, reflux condenser, nitrogen inlet tube, inlet tube, and thermometer, 54.5 g of sebacic acid, 6.4 g of trimesic acid, preamine 1074: C36 dimer diamine (manufactured by Croda Japan Co., Ltd.) (Amine value: 210 mg KOH / g) 148.4 g and 100 g of ion-exchanged water were charged, and the mixture was stirred until the temperature of heat generation became constant. When the temperature was stabilized, the temperature was raised to 110 ° C., and after confirming the outflow of water, the temperature was raised to 120 ° C. after 30 minutes, and then the dehydration reaction was continued while raising the temperature by 10 ° C. every 30 minutes. . When the temperature reached 230 ° C., the reaction was continued for 3 hours at the same temperature, and held for 1 hour under a vacuum of about 2 KPa. Thereafter, the temperature was lowered to obtain a polyamide resin. The mass average molecular weight was 28,000, and the acid value was 20.0 mgKOH / g.

[Synthesis Examples 16 to 17]
Synthesis was performed in the same manner as in Synthesis Example 15 in accordance with the composition shown in Table 5 to obtain a polyamide resin.

[Synthesis Example 18]
<Synthesis example of polyimide resin>
In a four-necked flask equipped with a stirrer, reflux condenser, nitrogen inlet pipe, inlet pipe, and thermometer, 88.8 g of 4,4 ′-(hexafluoroisopropylidene) diphthalic anhydride “6FDA”, dimer isocyanate (BASF) Japan Co., Ltd., NCO% = 13.8%) 110.1 g IPDI nurate (nuphorate of isophorone diisocyanate) 6.06 g was charged and stirred until the temperature of heat generation became constant. When the temperature was stabilized, the temperature was raised to 110 ° C., and after confirming the outflow of water, the temperature was raised to 120 ° C. after 30 minutes, and then the dehydration reaction was continued while raising the temperature by 10 ° C. every 30 minutes. . When the temperature reached 230 ° C., the reaction was continued for 3 hours at the same temperature, and kept under a vacuum of about 2 kPa for 3 hours. Thereafter, the temperature was lowered to obtain a polyimide resin. The mass average molecular weight was 34,000, and the acid anhydride value was 7.5 mgKOH / g.

[Synthesis Examples 19 to 23]
Synthesis was performed according to the composition shown in Table 6 in the same manner as in Synthesis Example 18 to obtain a polyimide resin.

[Synthesis Example 24]
<Synthesis example of polycarbonate resin>
In a four-necked flask equipped with a stirrer, reflux condenser, nitrogen inlet tube, inlet tube, thermometer, ethylene carbonate 25.2 g, 1,4-cyclohexanedimethanol 38.9 g, trimethylolpropane 4.0 g, The transesterification was carried out for 8 hours while adding 0.003 g of tetrabutyl titanate and distilling off a mixture of cyclohexanedimethanol and ethylene carbonate under normal pressure and stirring. During this time, the temperature of the reaction is gradually raised to 190 ° C. while raising the temperature by 10 ° C. every 30 minutes, so that the composition of the distillate is close to the azeotropic composition of the mixture of cyclohexanedimethanol and ethylene carbonate. Adjusted. The reaction was continued for 3 hours at the same temperature, and was further maintained for 3 hours under a vacuum of about 2 KPa. Thereafter, the temperature was lowered to obtain a polycarbonate resin. The mass average molecular weight was 14,000, and the hydroxyl value was 48.2 mgKOH / g.

[Synthesis Example 25]
<Synthesis example of polycarbonate resin>
A 4-neck flask equipped with a stirrer, reflux condenser, nitrogen inlet tube, inlet tube, and thermometer was charged with 25.2 g of ethylene carbonate, 35.5 g of 1.6-hexanediol, and 0.003 g of tetrabutyl titanate. The ester exchange reaction was carried out for 8 hours while distilling off a mixture of 1.6 hexanediol and ethylene carbonate under pressure and stirring. During this period, the reaction temperature is gradually raised to 190 ° C. while raising the temperature by 10 ° C. every 30 minutes, and the composition of the distillate is close to the azeotropic composition of the mixture of 1.6-hexanediol and ethylene carbonate. Adjusted as follows. The reaction was continued for 3 hours at the same temperature, and was further maintained for 3 hours under a vacuum of about 2 KPa. Thereafter, the temperature was decreased, 2.2 g of trimellitic anhydride and 30 g of toluene were added and reacted at 110 ° C. for 3 hours, and then the temperature was decreased to obtain a polycarbonate resin. The mass average molecular weight was 13,000, the acid value was 20.4 mgKOH / g, and the hydroxyl value was 15.3 mgKOH / g.

[Synthesis Example 26]
<Synthesis example of polyphenylene ether resin>
A four-necked flask equipped with a stirrer, a reflux condenser, a nitrogen inlet tube, an inlet tube, and a thermometer was placed in a constant temperature water bath at 30 ° C. 9.9 g of copper (I) chloride was added to 2.0 g of pyridine, stirred while blowing oxygen, and 5.0 g of toluene was added to obtain a copper (II) pyridine complex solution serving as a catalyst solution. In addition, 98.0 g of 2,6-dimethylphenol and 30.0 g of 2.2-bis (4-hydroxy-3,5-dimethylphenyl) propane were dissolved in 3.0 g of toluene to obtain a phenol solution. Thereafter, both the catalyst and phenol solutions were added dropwise and mixed vigorously in a reaction vessel maintained at 30 ° C. and purged with oxygen. 66 minutes after the start of monomer addition, the oxygen was switched to nitrogen to stop the polymerization. The reaction solution was dropped into 110 g of methanol containing 0.3 g of concentrated hydrochloric acid. The precipitated polymer was filtered and washed with 25.0 g methanol, then 25.0 g methanol containing 1.0 g concentrated hydrochloric acid and finally 25.0 g methanol. It was dried at 120 ° C. for 3 hours and diluted with 50.0 g of toluene and 50.0 g of 2-propanol to obtain a polyphenylene ether resin. The mass average molecular weight was 15,000, and the phenolic hydroxyl value was 15.4 mgKOH / g.

[Synthesis Example 27] <Synthesis Example of Styrenic Elastomer>
With respect to the block ratio of the polymer (hereinafter the same), styrene: butadiene = 15: 85 (mass%), 100 g of styrene elastomer having a mass average molecular weight of 60000, maleic anhydride 0.49 g, benzoyl peroxide 0.1 g, iruga 0.6 g of Knox 1010 (manufactured by BASF Japan, antioxidant) was dry blended, further mixed and melt-kneaded using a vented 32 mm twin screw extruder to obtain a pellet sample. The temperature of the twin screw extruder at the time of mixing and melt kneading was set to 40 ° C. below the hopper, 80 ° C. mixing zone, 170 ° C. reaction zone, and 180 ° C. die.
To 100 parts by mass of the obtained pellet-like sample, 85 parts by mass of acetone and 85 parts by mass of heptane were added, and the mixture was heated and stirred at 85 ° C. for 2 hours in a pressure resistant reactor. After completion of the operation, the pellets were collected with a wire mesh and vacuum-dried at 140 ° C. and 0.1 Torr for 20 hours to obtain a styrene-butadiene block copolymer having an acid anhydride group. The molecular weight distribution was narrow, the mass average molecular weight was 60000, and the acid anhydride value was 2.8 mg CH ₃ ONa / g.

[Synthesis Example 28]
An acid anhydride having a mass average molecular weight and an acid anhydride base value as shown in Table 1 in the same manner as in Synthesis Example 1 except that the styrene elastomer used was styrene: isoprene = 15: 85 (mass%). A styrene-isoprene block copolymer having a group was obtained.

[Synthesis Example 29]
Except that the styrene elastomer used was styrene: [ethylene / butylene] = 15: 85 (mass%), the mass average molecular weight and acid anhydride value as shown in Table 1 were set in the same manner as in Synthesis Example 1. A styrene-ethylene / butylene-styrene block copolymer having an acid anhydride group was obtained.

[Synthesis Examples 30 to 33]
Styrene having an acid anhydride group having a mass average molecular weight and an acid anhydride group as shown in Table 9 in the same manner as in Synthesis Example 29 except that the amount of maleic anhydride used was changed and the amount of modification was changed. -An ethylene / butylene-styrene block copolymer was obtained.

[Synthesis Example 34]
<Synthesis example of fluororesin>
A 1000 mL stainless steel autoclave is charged with 35.2 g of hexafluoropropylene, 46.5 g of vinyl pivalate, 4.93 g of hydroxybutyl vinyl ether, 12.7 g of ethyl vinyl ether, 0.7 g of crotonic acid and 0.8 g of diisopropyl peroxydicarbonate. After cooling to 0 ° C., the mixture was degassed under reduced pressure. Then, under stirring, 40
The reaction was stopped when the reactor internal pressure dropped from 5 kg / cm ² to 2 kg / cm ² , and a fluororesin was obtained. The mass average molecular weight was 48,000, and the acid value was 4.6 mgKOH / g.

[Synthesis Example 35]
<Synthesis example of fluororesin>
Synthesis was performed according to the composition shown in Table 10 in the same manner as in Synthesis Example 34 to obtain a fluororesin.

[Synthesis Example 36]
<Synthesis Example of Styrene Maleic Anhydride Resin>
In a 4-neck flask equipped with a stirrer, reflux condenser, nitrogen inlet tube, inlet tube, and thermometer, 300 g of MEK was placed, heated to 80 ° C. while injecting nitrogen gas into the vessel, and 516.1 g of styrene at the same temperature. Then, a mixture of 48.4 g of maleic anhydride and 0.2 g of benzoyl peroxide was added dropwise over 1 hour to carry out a polymerization reaction. After completion of the dropwise addition, the mixture was further reacted at 80 ° C. for 3 hours, and then 0.2 g of benzoyl peroxide dissolved in 50 g of MEK was added and reacted at 80 ° C. for 1 hour to obtain a styrene maleic anhydride resin solution. It was. The weight average molecular weight was 62,000, and the acid anhydride value was 49.0 mgKOH / g.

[Synthesis Examples 37 to 38]
<Synthesis Example of Styrene Maleic Anhydride Resin>
Synthesis was performed according to the composition shown in Table 11 in the same manner as in Synthesis Example 36 to obtain a styrene maleic anhydride resin.

Hereinafter, in Tables 1 to 11, common BMA: n-butyl methacrylate MMA: methyl methacrylate LMA: lauryl methacrylate TDMA: tridecyl methacrylate LMA / TDMA = 1/1 mixture tBA: ter-butyl acrylate MAA: methacrylic acid HEMA: 2- Hydroxyethyl methacrylate AIBN: Azobisisobutyronitrile preporal 2033: C36 dimer diol (OH value: 20) manufactured by Croda Japan Co., Ltd.
7mgKOH / g)
Pripol 1009: C36 dimer acid (acid value: 195.0m), manufactured by Croda Japan
gKOH / g)
TDI: tolylene diisocyanate TMA: trimellitic anhydride preamine 1074: manufactured by Claude Japan, C36 dimer diamine (amine value: 2)
10mgKOH / g)
NBDA: norbornanediamine bisaniline M: manufactured by Mitsui Chemicals Fine Co., Ltd., 1,3-bis [2- (4-aminophenyl) -2-propyl] benzene IPDI nurate: nurate Wandamine HM of isophorone diisocyanate HM: Shin Nippon Rika 4,4'-diaminodicyclohexylmethane KF-8010 manufactured by Shin-Etsu Silicone Co., Ltd., both terminal amino-modified silicone oil (amine value: 430 mgKOH / g)
HAB: 4,4′-diamino-3,3′-dihydroxybiphenyl 1,6-HD: 1,6-hexanediol 2,6-DMP: 2,6-dimethylphenol BXF: 2,2-bis (4-hydroxy -3,5-dimethylphenyl) propane

Example 1
As a curing agent (B), jER1031S (manufactured by Mitsubishi Chemical Corporation, tetrafunctional tetrakisphenol type epoxy) with respect to 1 mol of the reactive functional group in the styrene-based elastomer obtained in Synthesis Example 30 which is the resin (A). Compound) is added in an amount of 1.1 mol of epoxy groups, lithium carbonate is added as an alkali metal compound (C), and dissolved in a cyclohexanone solvent so that the solid concentration is 25%. I adjusted things.
This thermosetting composition was uniformly applied onto a release-treated polyester film so that the film thickness after drying was 30 μm and dried to provide an adhesive sheet. Next, another release-treated polyester film was laminated on the adhesive sheet to obtain an adhesive sheet with a double-sided protective film.
In addition, when the amount of lithium in the solid content of the thermosetting composition was determined by ICP emission spectroscopic analysis according to the following procedure, it was 50 ppm.

After removing the double-sided protective film from the adhesive sheet prepared above and weighing about 0.25 g in a Teflon container of a microwave sample disassembly device (TOPwave manufactured by Analytic Jena), add 7 ml of nitric acid and let stand for 1 hour. , Put in a dedicated lid, outer container and installed in the device. Heat treatment was performed at 200 ° C. for 10 minutes in the apparatus. Then, it is cooled to room temperature, the treatment liquid is put into a 50 ml volumetric flask, and the treated Teflon container is put into the volumetric flask while washing with ultrapure water. To prepare a measurement sample. Thereafter, the treatment liquid was measured with an ICP analyzer (manufactured by SPECTRO, AECOS), and the amount of alkali metal element in the adhesive sheet was quantified using a calibration curve prepared with a standard solution of the target element.

[Examples 2 to 8]
An adhesive sheet with a double-sided protective film was prepared in the same manner as in Example 1 except that the alkali metal compound (D) shown in Table 12 was added instead of the lithium carbonate used in Example 1.

[Comparative Example 1]
An adhesive sheet with a double-sided protective film was prepared in the same manner as in Example 1 except that lithium carbonate was not added.

[Comparative Examples 2 to 4]
An adhesive sheet with a double-sided protective film was prepared in the same manner as in Example 1 except that the alkaline earth metal compounds shown in Table 12 were added in place of the lithium carbonate used in Example 1, respectively.

[Examples 9 to 16], [Comparative Examples 5 to 8]
As shown in Table 13, in the same manner as in Examples 1-8 and Comparative Examples 1-4, except that the polyphenylene ether resin obtained in Synthesis Example 26 was used instead of the styrene elastomer obtained in Synthesis Example 30. Thus, an adhesive sheet with a double-sided protective film was prepared.

[Examples 17 to 24], [Comparative Examples 9 to 12]
As shown in Table 14, using the styrene-based elastomer obtained in Synthesis Example 30 and changing the amount of the alkali metal compound, the alkaline earth metal compound, etc. An adhesive sheet was prepared.

[Examples 25 to 32], [Comparative Examples 13 to 16]
As shown in Table 15, with a double-sided protective film in the same manner as in Example 9, except that the polyphenylene ether-based resin obtained in Synthesis Example 26 was used and the amounts of alkali metal compounds and alkaline earth metal compounds were changed. An adhesive sheet was prepared.

[Examples 33 to 40]
As shown in Table 16, an adhesive sheet with a double-sided protective film was prepared in the same manner as in Example 1 except that the styrene elastomer obtained in Synthesis Example 30 was used and two kinds of alkali metal compounds were used in combination.

[Examples 41 to 48]
As shown in Table 17, an adhesive sheet with a double-sided protective film was prepared in the same manner as in Example 9 except that the polyphenylene ether resin obtained in Synthesis Example 26 was used and two kinds of alkali metal compounds were used in combination.

[Examples 49 to 51], [Comparative Example 17]
As shown in Table 18, Example 1 except that the styrene-based elastomer obtained in Synthesis Example 30 was used and, as an epoxy group-containing compound (C), another epoxy group-containing compound described later was used instead of jER1031S. In the same manner as described above, an adhesive sheet with a double-sided protective film was prepared.
Example 18 is also shown in Table 18.

[Examples 52 to 58], [Comparative Example 18]
As shown in Table 19, Examples were used except that the polyphenylene ether-based resin obtained in Synthesis Example 26 was used, and another epoxy group-containing compound described later was used as the epoxy group-containing compound (C) instead of jER1031S. In the same manner as in Example 9, an adhesive sheet with a double-sided protective film was prepared.
In addition, Example 9 is also shown in Table 19.

[Examples 59 to 68]
As shown in Table 20, an adhesive sheet with a double-sided protective film was used in the same manner as in Example 1 except that the styrene-based elastomer obtained in Synthesis Example 30 was used and the type and amount of the curing agent (B) were changed. Created.

[Examples 69 to 83]
As shown in Table 21, an adhesive sheet with a double-sided protective film was used in the same manner as in Example 9 except that the polyphenylene ether-based resin obtained in Synthesis Example 26 was used and the type and amount of the curing agent (B) were changed. It was created.

[Examples 84 to 108], [Examples 115 to 119]
As shown in Tables 22-28 and 30-31, instead of the styrene-based elastomer obtained in Synthesis Example 30, each resin obtained in Synthesis Examples 1-25 and 34-38 as resin (A) was replaced with jER1031S. Example 1 except that, as a curing agent (B), BL4265SN: manufactured by Sumika Bayer Urethane Co., Ltd., an isophorone diisocyanate (hereinafter also referred to as IPDI) polyfunctional type was blocked with methyl ethyl ketone oxime was used. Similarly, an adhesive sheet with a double-sided protective film was prepared.

[Examples 109 to 114]
As shown in Table 29, with a double-sided protective film in the same manner as in Example 1 except that the styrene elastomer obtained in Synthesis Examples 29 to 33 was used instead of the styrene elastomer obtained in Synthesis Example 30. An adhesive sheet was prepared.

[Examples 120 to 125]
As shown in Table 32, each resin obtained in Synthesis Examples 29, 26, 15, 20, 34, 11, and 1 was used as the resin (A) instead of the styrene-based elastomer obtained in Synthesis Example 30. Except that, an adhesive sheet with a double-sided protective film was prepared in the same manner as in Example 49.
Example 52 is also shown in Table 32.

Hereinafter, it is common in Tables 12-32.
jER1031S: manufactured by Mitsubishi Chemical Corporation, tetrafunctional tetrakisphenol type epoxy compound TETRAD-X: manufactured by Mitsubishi Gas Chemical Co., Ltd., tetrafunctional glycidylamine compound BL4265SN: manufactured by Sumika Bayer Urethane Co., Ltd., isophorone diisocyanate (hereinafter referred to as IPDI) Isocyanate BL3175 blocked with methyl ethyl ketone oxime: manufactured by Sumika Bayer Urethane Co., Ltd., hexamethylene diisocyanate
Isocyanate BL1100 obtained by blocking a trimer (nurate) of HDI) with methyl ethyl ketone oxyk: a product made by Sumika Bayer Urethane Co., Ltd., a prepolymer type of tolylene diisocyanate (hereinafter also referred to as TDI). Isocyanate OXTP blocked with caprolactam: manufactured by Ube Industries, Ltd., bifunctional oxetane compound OXT-121: manufactured by Toa Gosei Co., Ltd., bifunctional oxetane compound Chemitite PZ: manufactured by Nippon Shokubai Co., Ltd., polyfunctional aziridine compound

  About the adhesive sheet obtained by the Example and the comparative example, plating solution tolerance, adhesiveness, heat resistance, flexibility, and electrical insulation were evaluated by the following methods. The results are shown in Tables 21-52.

<Evaluation>

(1) Resistance to plating solution An adhesive sheet having a size of 65 mm × 65 mm from which the protective film on one side has been removed is placed on a two-layer CCL [Espanex MC18-25-00FRM] copper surface manufactured by Nippon Steel & Sumikin Chemical Co., Ltd. Lamination was performed at 80 ° C., followed by a pressure bonding treatment at 160 ° C. and 1.0 MPa for 30 minutes. Furthermore, this test piece was heat-cured at 160 ° C. for 2 hours, and finally the protective film was peeled off to prepare an evaluation test piece. The test piece was subjected to electroless nickel treatment according to the following procedures and conditions a to g.
a. Acid degreasing process: Immersion in ICP Clean S-135K (Okuno Pharmaceutical Co., Ltd.) at 40 ° C for 4 minutes ↓
b. Soft etching process: Soaked in sodium persulfate at 30 ° C for 1 minute ↓
c. Desmut process: Immerse in sulfuric acid at 25 ° C for 1 minute ↓
d. Pre-dip process: Immerse in hydrochloric acid at 25 ℃ for 30 seconds ↓
e. Activation process: Immersion in 30 ° C ICP Axela (Okuno Pharmaceutical Co., Ltd.) ↓
f. Post-dip process: 1 minute immersion in sulfuric acid at 25 ° C ↓
g. Electroless nickel plating process: Immersion in 85 ° C IP Nicolon FPF (Okuno Pharmaceutical Co., Ltd.) for 20 minutes.

The appearance of the test piece after immersion in the electroless nickel plating solution was visually observed, and after curing, the presence or absence of abnormalities such as swelling and peeling of the adhesive layer was confirmed. For those having no abnormality, the steps a to g were further repeated. .
This test evaluates the resistance of the adhesive layer after curing to the plating solution by appearance, and the resistance was evaluated by the number of repetitions of a to g.
A: No poor appearance after the fourth immersion.
B: No appearance defect in the third immersion, but occurs after the fourth immersion.
C: No appearance defect in the second immersion, but occurs after the third immersion.
D: No appearance defect in the first immersion, but occurs after the second immersion.
E: Appearance defect occurred in the first immersion.

(2) Adhesive A 65 mm × 65 mm adhesive sheet with the protective film removed is sandwiched between 75 μm thick polyimide film [“Kapton 300H” manufactured by Toray DuPont Co., Ltd.] at 80 ° C. Lamination was performed, followed by pressure bonding at 160 ° C. and 1.0 MPa for 30 minutes. Furthermore, this test piece was heat-cured at 160 ° C. for 2 hours to prepare an evaluation test piece. This test piece was cut out to a width of 10 mm and a length of 65 mm, and a T peel peel test was performed at an elongation rate of 300 mm / min in an atmosphere of 23 ° C. and a relative humidity of 50%, and the adhesive strength (N / cm) was measured. This test evaluates the adhesive strength of the adhesive layer when used at room temperature, and the results were judged according to the following criteria.
A ... "12 (N / cm) <Adhesive strength"
B: “8 (N / cm) <Adhesion strength ≦ 12 (N / cm)”
C: “5 (N / cm) <Adhesion strength ≦ 8 (N / cm)”
D: “3 (N / cm) <Adhesion strength ≦ 5 (N / cm)”
E ... "Adhesive strength ≤ 3 (N / cm)"

(3) Heat resistance As in (2) above, test pieces cut out to a width of 10 mm and a length of 65 mm are stored for 24 hours or more in an atmosphere of 23 ° C. and 50% relative humidity, and then molten solder at various temperatures. The polyimide film surface was brought into contact with and floated for 1 minute. Then, the external appearance of the test piece was observed visually, and the presence or absence of adhesion abnormality such as foaming, floating, and peeling of the cured adhesive layer was evaluated. This test evaluates the thermal stability of the cured adhesive layer at the time of solder contact by appearance. Good heat resistance does not change the appearance, while poor heat resistance has no solder. Foaming or peeling occurs after treatment. These evaluation results were judged according to the following criteria.
A ... "No change in appearance even at 300 ° C"
B: “No change in appearance at 280 ° C. Foaming is confirmed at 300 ° C.”
C: "No change in appearance even at 260 ° C. Foaming is confirmed at 280 ° C" D: "No change in appearance at 240 ° C. Foaming is confirmed at 260 ° C" E: "240 Foaming is observed at ℃. ''

(4) Flexibility A 65 mm x 65 mm adhesive sheet from which the protective film has been removed is formed on a polyimide film with a thickness of 25 μm ["Kapton 100H" manufactured by Toray DuPont Co., Ltd.] and a polyimide circuit. Between the printed comb pattern (conductor pattern width / space width = 50 μm / 50 μm) and printed wiring board, laminated at 80 ° C., and subsequently subjected to a pressure bonding treatment at 160 ° C. and 1.0 MPa for 30 minutes. . Furthermore, this test piece was heat-cured at 160 ° C. for 2 hours to prepare an evaluation test piece. The test piece for evaluation was bent 180 degrees with a load of 500 g with the cured coating surface facing outward, and the number of times until cracking occurred was evaluated according to the following criteria.
A ... "No cracks are seen even after bending 20 times"
B ... "No cracks are seen even after bending 14 times. Cracks occur up to 20 times"
C ... "No cracks are seen even if bent 8 times. Cracks occur up to 14 times"
D: “No cracks are seen even if bent 3 times. Cracks occur up to 8 times”
E ... "Crack occurs before bending 3 times"

(5) Electrical insulation The 65 mm x 65 mm adhesive sheet, from which the protective film has been removed, is a 25 µm thick polyimide film ["Kapton 100H" manufactured by Toray DuPont Co., Ltd.] and a copper circuit on the polyimide. It is sandwiched between the formed comb pattern (conductor pattern width / space width = 50 μm / 50 μm) and printed wiring board, laminated at 80 ° C., and then subjected to crimping for 30 minutes at 160 ° C. and 1.0 MPa. It was. Furthermore, this test piece was heat-cured at 160 ° C. for 2 hours to prepare an evaluation test piece. A DC voltage of 50 V was continuously applied to the conductor circuit of this test piece for 100 hours under an atmosphere of a temperature of 130 ° C. and a relative humidity of 85%, and the insulation resistance value between the conductors after 100 hours was measured. The evaluation criteria are as follows.
A: Insulation resistance value 10 ⁹ Ω or more B ... Insulation resistance value 10 ⁸ or more and less than 10 ⁹ Ω C ... Insulation resistance value 10 ⁷ or more and less than 10 ⁸ Ω D ... Insulation resistance value 10 ⁶ or more 10 Less than ⁷ Ω E ・ ・ ・ Insulation resistance less than 10 ⁶

As can be seen from the examples and comparative examples shown in Tables 12 to 32, in Comparative Examples 1 and 5, since the alkali metal compound (C) was not used, the plating solution resistance deteriorated. Moreover, in Comparative Examples 2-4 and 6-8, since another metal compound was added instead of the alkali metal compound (C), plating solution tolerance deteriorated. Further, even when the alkali metal compound (C) was contained, as in Comparative Examples 9, 11, 13, and 15, when the content of the alkali metal compound (C) was less than 1 ppm, the plating solution resistance deteriorated. Moreover, when the alkali metal compound (C) was contained in excess of 110 ppm as in Comparative Examples 10, 12, 14, and 16, the electrical insulating properties deteriorated.
Further, as can be seen from Comparative Examples 17 and 18, when the curing agent (B) was not contained, the heat resistance and the insulation were significantly deteriorated.

On the other hand, as described in Examples, the resin (A), the curing agent (B), and the alkali metal compound (C) are contained, and the alkali metal compound (C) is contained in an amount of 1 to 110 ppm in terms of the mass of the alkali metal element. In this case, in addition to the compatibility of the plating solution resistance and electrical insulation, which were in contradiction in the comparative example, the adhesiveness, heat resistance, and flexibility were satisfied. This is because the resin (A) and the curing agent (B) provide adhesiveness, heat resistance and flexibility, and further contains an alkali metal compound (C), thereby forming a metal crosslink when immersed in the plating solution, This is probably because a stronger film could be formed.

The thermosetting composition used for forming the adhesive sheet of the present invention provides a cured product excellent in plating solution resistance, adhesiveness, heat resistance after humidification, heat resistance, flexibility, and electrical insulation. It can be suitably used for coating materials for electronic materials including boards, solder resists for circuit coating, coverlay films, adhesives for electromagnetic wave shields, plating resists, interlayer electrical insulation materials for printed wiring boards, optical waveguides, etc. .

Claims (9)

A thermosetting adhesive sheet formed from a thermosetting composition that satisfies all of the following conditions (1) to (5).
(1) A resin (A), a curing agent (B), and an alkali metal compound (C) are included.
(2) The curing agent (B) is at least one selected from the group consisting of an epoxy group-containing compound, an isocyanate group-containing compound, an aziridinyl group-containing compound, and an oxetanyl group-containing compound.
(3) The resin (A) does not have an epoxy group, an isocyanate group, an aziridinyl group, and an oxetanyl group, and has a reactive functional group that can react with the curing agent (B).
(4) The resin (A) is an acrylic resin, a polyester resin, a polyurethane resin, a polyurethane polyurea resin, a polyamide resin, a polyimide resin, a polycarbonate resin, a polyphenylene ether resin, a styrene elastomer, a fluorine resin, and a styrene maleic anhydride resin. Is at least one selected from the group consisting of
(5) The alkali metal compound (C) is contained in an amount of 1 to 110 ppm in terms of the mass of the alkali metal element in the solid content of the thermosetting composition.   The thermosetting adhesive sheet according to claim 1, wherein the reactive functional group is at least one selected from the group consisting of a carboxyl group, an alcoholic hydroxyl group, a phenolic hydroxyl group, and an acid anhydride group.   The thermosetting adhesive sheet according to claim 1 or 2, wherein the total reactive functional group value of 1 g of the resin (A) is 1 to 80 mg in terms of potassium hydroxide.   The total of the epoxy group, isocyanate group, aziridinyl group, and oxetanyl group in the curing agent (B) is 0.1 to 12 mol with respect to 1 mol of the reactive functional group of the resin (A). The thermosetting adhesive sheet according to item 1.   The thermosetting adhesive sheet with a sheet-like base material which has the thermosetting adhesive sheet of any one of Claims 1-4, and two sheet-like base materials which cover both surfaces of the said thermosetting adhesive sheet.   The thermosetting adhesive sheet with a sheet-like substrate according to claim 5, wherein at least one of the two sheet-like substrates is a peelable sheet-like substrate. A thermosetting composition satisfying all of the following conditions (1) to (5) is applied to at least one surface of the sheet-like base material, dried to form a thermosetting adhesive sheet, and the thermosetting adhesive sheet A method for producing a thermosetting adhesive sheet with a sheet-like substrate, wherein another sheet-like substrate is stacked on the other surface of the sheet.
(1) A resin (A), a curing agent (B), and an alkali metal compound (C) are included.
(2) The curing agent (B) is at least one selected from the group consisting of an epoxy group-containing compound, an isocyanate group-containing compound, an aziridinyl group-containing compound, and an oxetanyl group-containing compound.
(3) The resin (A) does not have an epoxy group, an isocyanate group, an aziridinyl group, and an oxetanyl group, and has a reactive functional group that can react with the curing agent (B).
(4) The resin (A) is an acrylic resin, a polyester resin, a polyurethane resin, a polyurethane polyurea resin, a polyamide resin, a polyimide resin, a polycarbonate resin, a polyphenylene ether resin, a styrene elastomer, a fluorine resin, and a styrene maleic anhydride resin. Is at least one selected from the group consisting of
(5) The alkali metal compound (D) is contained in an amount of 1 to 110 ppm in terms of the mass of the alkali metal element in the solid content of the thermosetting composition.   The said circuit surface of the printed wiring board which has a conductive circuit is a sheet-like base material through the sheet-like hardened | cured material formed by thermosetting the thermosetting adhesive sheet of any one of Claims 1-4. Protected printed wiring board with protective sheet. The thermosetting adhesive sheet according to any one of claims 1 to 4 is sandwiched between the circuit surface of a printed wiring board having a conductive circuit and a sheet-like base material, and the thermosetting adhesive sheet is A method for producing a printed wiring board with a protective sheet, which is thermoset.