JPWO2016129541A1 - Thermosetting resin composition - Google Patents

Abstract

The present invention includes (A) a polyimide resin having a structure represented by formula (1-a) and a structure represented by formula (1-b), and (B) an epoxy resin, a bismaleimide resin, a cyanate ester resin, Provided is a thermosetting resin composition containing at least one thermosetting resin selected from a bisallyl nadiimide resin, a vinyl benzyl ether resin, a benzoxazine resin, and a polymer of bismaleimide and a diamine (the following formula The definition of the group in it is as described in the specification).

Description

  The present invention relates to a thermosetting resin composition useful for forming an insulating layer of a circuit board such as a coreless circuit board, a flexible circuit board, or a wafer level chip size package.

  Insulating layers and the like used for circuit boards such as coreless circuit boards, flexible circuit boards, and wafer level chip size packages have a low coefficient of thermal expansion (CTE) and low elastic modulus in order to suppress the warpage of the board. It is required to have. As an insulating resin material for forming such an insulating layer, for example, Patent Document 1 discloses a resin composition containing an expansion relaxation component made of an acrylic resin that is soluble in an organic solvent. However, an insulating layer formed of a conventional insulating resin material has a problem that it has high water repellency and repels highly hydrophilic ink.

International Publication No. 2014/132654

  The present invention has been made paying attention to the above-described circumstances, and an object thereof is to provide a thermosetting resin composition capable of forming an insulating layer having high hydrophilicity.

  As a result of intensive studies by the present inventors in order to solve the above problems, a highly hydrophilic insulating layer is formed from a thermosetting resin composition that uses a polyimide resin having a specific structure and an epoxy resin or the like in combination. It has been found that it can be formed. The present invention based on this finding is as follows.

  [1] (A) Structure represented by formula (1-a) and structure represented by formula (1-b):

[Wherein R1 represents a residue obtained by removing a hydroxy group of a polycarbonate diol, R2 represents a residue obtained by removing a carboxy group or an acid anhydride group of a polybasic acid or its anhydride, and R3 represents an isocyanate of a diisocyanate compound. The residue without a group is shown. ]
And (B) one or more selected from epoxy resin, bismaleimide resin, cyanate ester resin, bisallyl nadiimide resin, vinyl benzyl ether resin, benzoxazine resin, and a polymer of bismaleimide and diamine A thermosetting resin composition containing a thermosetting resin.

  [2] The polyimide resin as component (A) is represented by the formula (abc):

[Wherein, R1 to R3 are as described in [1] above, and n and m represent integers. ]
The thermosetting resin composition according to [1], which has a structure represented by:

[3] The thermosetting resin composition according to [1] or [2], wherein the number average molecular weight of the polycarbonate diol is 500 to 5,000.
[4] The thermosetting resin composition according to [1] or [2], wherein the polycarbonate diol has a number average molecular weight of 1,000 to 3,000.

  [5] R1 is represented by the formula (1-c):

[Wherein, k + 1 R4 each independently represents an optionally substituted alkylene group having 1 to 20 carbon atoms, and k represents an integer of 5 to 30. ]
The thermosetting resin composition according to any one of [1] to [4], which is a divalent group represented by:

[6] The thermosetting resin composition according to [5], wherein k + 1 R4s are each independently an alkylene group having 1 to 20 carbon atoms.
[7] The thermosetting resin composition according to [5], wherein k + 1 R4s are each independently an alkylene group having 2 to 18 carbon atoms.
[8] The thermosetting resin composition according to [5], wherein k + 1 R4s are each independently an alkylene group having 3 to 16 carbon atoms.

[9] The thermosetting resin composition according to any one of [5] to [8], wherein k is an integer of 5 to 25.
[10] The thermosetting resin composition according to any one of [5] to [8], wherein k is an integer of 5 to 20.

  [11] R2 is represented by the following formula:

[Wherein, A is an oxygen atom, a sulfur atom, CO, SO, SO ₂ , CH ₂ , CH (CH ₃ ), C (CH ₃ ) ₂ , C (CF ₃ ) ₂ , or C (CCl ₃ ) ₂ Indicates. In the formula, a hydrogen atom bonded to a carbon atom may be substituted with a substituent selected from a halogen atom and an alkyl group having 1 to 8 carbon atoms. ]
The thermosetting resin composition according to any one of [1] to [10], which is one or more selected from the group of tetravalent groups represented by any of the above:

  [12] R2 is represented by the following formula:

[Wherein, A is an oxygen atom, a sulfur atom, CO, SO, SO ₂ , CH ₂ , CH (CH ₃ ), C (CH ₃ ) ₂ , C (CF ₃ ) ₂ , or C (CCl ₃ ) ₂ Represents. In the formula, a hydrogen atom bonded to a carbon atom may be substituted with a substituent selected from a halogen atom and an alkyl group having 1 to 8 carbon atoms. ]
The thermosetting resin composition according to any one of [1] to [10], which is a tetravalent group represented by:

[13] In the above formula, A represents an oxygen atom, a sulfur atom, CO, SO, SO ₂ , CH ₂ , CH (CH ₃ ), C (CH ₃ ) ₂ , C (CF ₃ ) ₂ , or C (CCl ₃ ) The thermosetting resin composition according to [11] or [12], in which ₂ is a hydrogen atom bonded to a carbon atom and is not substituted.
[14] The thermosetting resin composition according to [11] or [12], wherein A is CO, and a hydrogen atom bonded to a carbon atom is not substituted.

  [15] R3 is represented by the following formula:

[Wherein, the hydrogen atom bonded to the carbon atom may be substituted with a substituent selected from a halogen atom and an alkyl group having 1 to 8 carbon atoms. ]
The thermosetting resin composition according to any one of [1] to [14], which is one or more selected from the group of divalent groups represented by any of the above:

  [16] The thermosetting resin composition according to [15], wherein the substituent selected from a halogen atom and an alkyl group having 1 to 8 carbon atoms is an alkyl group having 1 to 8 carbon atoms.

  [17] R3 is

[Wherein, a hydrogen atom bonded to a carbon atom may be substituted with an alkyl group having 1 to 8 carbon atoms. ]
The thermosetting resin composition according to any one of [1] to [14], which is one or more selected from the group of divalent groups represented by any of the above:

[18] The thermosetting resin composition according to any one of [15] to [17], wherein the alkyl group having 1 to 8 carbon atoms is an alkyl group having 1 to 6 carbon atoms.
[19] The thermosetting resin composition according to any one of [15] to [17], wherein the alkyl group having 1 to 8 carbon atoms is a methyl group.

  [20] The thermosetting resin composition according to any one of [1] to [14], wherein R3 is a 4-methyl-1,3-phenylene group.

[21] The thermosetting resin composition according to any one of [1] to [20], wherein the polyimide resin as the component (A) has a number average molecular weight of 5,000 to 25,000.
[22] The thermosetting resin composition according to any one of [1] to [20], wherein the polyimide resin as the component (A) has a number average molecular weight of 5,000 to 20,000.

[23] The thermosetting resin composition according to any one of [1] to [22], wherein the polyimide resin as the component (A) has a glass transition temperature of 30 ° C. or lower.
[24] The thermosetting resin composition according to any one of [1] to [22], wherein the polyimide resin as the component (A) has a glass transition temperature of −15 ° C. to 29 ° C.
[25] The thermosetting resin composition according to any one of [1] to [22], wherein the polyimide resin as the component (A) has a glass transition temperature of −10 ° C. to 20 ° C.

  [26] The thermosetting resin composition according to any one of [1] to [25], wherein the thermosetting resin as the component (B) is an epoxy resin.

[27] The thermosetting resin composition according to [26], wherein the epoxy resin has an epoxy equivalent of 90 to 500.
[28] The thermosetting resin composition according to [26], wherein the epoxy equivalent of the epoxy resin is 90 to 300.
[29] The thermosetting resin composition according to [26], wherein the epoxy equivalent of the epoxy resin is 110 to 250.

  [30] The thermosetting resin composition according to any one of [26] to [29], wherein the epoxy resin is a liquid epoxy resin.

[31] Any of [1] to [30], wherein the content of the thermosetting resin as the component (B) is 15 to 80 parts by weight with respect to 100 parts by weight of the polyimide resin as the component (A). The thermosetting resin composition as described in any one.
[32] Any of [1] to [30], wherein the content of the thermosetting resin as the component (B) is 30 to 80 parts by weight with respect to 100 parts by weight of the polyimide resin as the component (A). The thermosetting resin composition as described in any one.
[33] Any of [1] to [30], wherein the content of the thermosetting resin as the component (B) is 40 to 70 parts by weight with respect to 100 parts by weight of the polyimide resin as the component (A). The thermosetting resin composition as described in any one.

[34] The thermosetting resin composition according to any one of [1] to [33], further including an inorganic filler.
[35] The thermosetting resin composition according to [34], wherein the inorganic filler is silica.

[36] The thermosetting resin composition according to [34] or [35], wherein the content of the inorganic filler is 50 to 95% by weight in the nonvolatile content of the thermosetting resin composition.
[37] The thermosetting resin composition according to [34] or [35], wherein the content of the inorganic filler is 60 to 93% by weight in the nonvolatile content of the thermosetting resin composition.
[38] The thermosetting resin composition according to [34] or [35], wherein the content of the inorganic filler is 70 to 90% by weight in the nonvolatile content of the thermosetting resin composition.
[39] The thermosetting resin composition according to [34] or [35], wherein the content of the inorganic filler is 80 to 85% by weight in the nonvolatile content of the thermosetting resin composition.

  [40] The thermosetting resin composition according to any one of [1] to [39], further including a curing accelerator.

[41] The thermosetting resin according to [40], wherein the content of the curing accelerator is preferably 0.5 to 5 parts by weight with respect to 100 parts by weight of the thermosetting resin as the component (B). Composition.
[42] The thermosetting resin composition according to [40], wherein the content of the curing accelerator is preferably 1 to 3 parts by weight with respect to 100 parts by weight of the thermosetting resin as the component (B). .

[43] An adhesive film having a layer formed from the thermosetting resin composition according to any one of [1] to [42] on a support.
[44] A printed wiring board having a cured product formed from the thermosetting resin composition according to any one of [1] to [42] as an insulating layer.
[45] A wafer level chip size package having a cured product formed from the thermosetting resin composition according to any one of [1] to [42] as an insulating layer.

  An insulating layer having high hydrophilicity can be formed from the thermosetting resin composition of the present invention. Such a highly hydrophilic insulating layer can uniformly apply a highly hydrophilic ink, and is useful for a circuit board such as a wafer level chip size package.

  The thermosetting resin composition of the present invention includes a polyimide resin (component (A)) having a structure derived from a polycarbonate diol, a structure derived from a diisocyanate compound, and a structure derived from a polybasic acid or an anhydride thereof, and an epoxy. One or more thermosetting resins (component (B)) selected from resins, bismaleimide resins, cyanate ester resins, bisallyl nadiimide resins, vinyl benzyl ether resins, benzoxazine resins, and polymers of bismaleimides and diamines ) And both. Hereinafter, these will be described in order.

<(A) Polyimide resin>
The component (A) is represented by the structure represented by the formula (1-a) (urethane and carbonate structure, hereinafter may be abbreviated as “structure (1-a)”) and the formula (1-b). A polyimide resin having a structure (an imide structure, hereinafter sometimes abbreviated as “structure (1-b)”).

[Wherein R1 represents a residue obtained by removing a hydroxy group of a polycarbonate diol, R2 represents a residue obtained by removing a carboxy group or an acid anhydride group of a polybasic acid or its anhydride, and R3 represents an isocyanate of a diisocyanate compound. The residue without a group is shown. ]
Note that the terminal of the above chemical formula indicates a bonding position, not a methyl group. The same applies to other chemical formulas.

The polyimide resin as component (A) is
(A) polycarbonate diol (hereinafter sometimes referred to as “raw material (a)”),
(B) a diisocyanate compound (hereinafter sometimes referred to as “raw material (b)”), and (c) a polybasic acid or an anhydride thereof (hereinafter sometimes referred to as “raw material (c)”).
Can be used as a raw material. Only 1 type may be used for a component (A) and it may use 2 or more types together. In addition, any of the raw materials (a) to (c) may be used alone or in combination of two or more.

  The number average molecular weight of the polycarbonate diol as the raw material (a) is preferably 500 to 5,000, more preferably from the viewpoint of the flexibility of the cured product of the resin composition and the solvent solubility of the component (A). 1,000 to 3,000.

  In the present invention, the number average molecular weight is a value measured by a gel permeation chromatography (GPC) method (polystyrene conversion). Specifically, the number average molecular weight determined by the GPC method is LC-9A / RID-6A manufactured by Shimadzu Corporation as a measuring device, and Shodex K-800P / K-804L / K- manufactured by Showa Denko KK as a column. 804 L can be measured using chloroform as a mobile phase at a column temperature of 40 ° C. and calculated using a standard polystyrene calibration curve.

  The hydroxyl group equivalent of the polycarbonate diol is preferably 250 to 1,250, more preferably 500 to 1,000, from the viewpoints of flexibility of the cured product of the resin composition and chemical resistance.

  A commercially available product can be used as the polycarbonate diol. Examples of such commercially available products include C-1015N and C-2015N manufactured by Kuraray Co., Ltd., T-6002, T-4672, T-5562 manufactured by Asahi Kasei Chemicals Corporation, and CD205 manufactured by Daicel Corporation. CD205PL, CD205HL, CD210, CD210PL, Nippon Polyurethane Industry Co., Ltd. Nippon Run 981, 980R, and the like.

  Examples of the diisocyanate compound as the raw material (b) include aromatic diisocyanates such as toluene-2,4-diisocyanate, toluene-2,6-diisocyanate, xylylene diisocyanate, and diphenylmethane diisocyanate; aliphatic diisocyanates such as hexamethylene diisocyanate; And alicyclic diisocyanates such as isophorone diisocyanate. Of these, aromatic diisocyanates are preferred, and toluene-2,4-diisocyanate is more preferred.

  Examples of the polybasic acid which is the raw material (c) or its anhydride include pyromellitic acid, benzophenone tetracarboxylic acid, biphenyl tetracarboxylic acid, naphthalene tetracarboxylic acid, 5- (2,5-dioxotetrahydrofuryl)- Tribasic acids such as 3-methyl-cyclohexene-1,2-dicarboxylic acid and 3,3′-4,4′-diphenylsulfonetetracarboxylic acid and their anhydrides, trimellitic acid and cyclohexanetricarboxylic acid Acids and their anhydrides, 1,3,3a, 4,5,9b-hexahydro-5- (tetrahydro-2,5-dioxo-3-furanyl) -naphth (1,2-C) furan-1,3 -Dione etc. are mentioned. Among these, tetrabasic acid anhydrides are preferable, tetrabasic acid dianhydrides are more preferable, and benzophenone tetracarboxylic dianhydride is more preferable.

R1 is preferably of the formula (1-c):

[Wherein, k + 1 R4 each independently represents an optionally substituted alkylene group having 1 to 20 carbon atoms, and k represents an integer of 5 to 30. ]
It is a bivalent group represented by these.

  The alkylene group for R4 may be linear or branched. Examples of the substituent that the alkylene group of R4 may have include a halogen atom, a cycloalkyl group having 4 to 8 carbon atoms, and an aryl group having 6 to 14 carbon atoms. The alkylene group for R4 is preferably unsubstituted.

As a halogen atom, a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom are mentioned, for example.
Examples of the cycloalkyl group having 4 to 8 carbon atoms include a cyclopentyl group, a cyclohexyl group, and a cycloheptyl group.
Examples of the aryl group having 6 to 14 carbon atoms include a phenyl group, a 1-naphthyl group, a 2-naphthyl group, a 1-anthryl group, a 2-anthryl group, and a 9-anthryl group.

  k + 1 R4s are each independently preferably an alkylene group having 1 to 20 carbon atoms, more preferably an alkylene group having 2 to 18 carbon atoms, and still more preferably an alkylene group having 3 to 16 carbon atoms. . k is preferably an integer of 5 to 25, more preferably an integer of 5 to 20.

  R2 is preferably represented by the following formula:

[Wherein, A is an oxygen atom, a sulfur atom, CO, SO, SO ₂ , CH ₂ , CH (CH ₃ ), C (CH ₃ ) ₂ , C (CF ₃ ) ₂ , or C (CCl ₃ ) ₂ Indicates. In the formula, a hydrogen atom bonded to a carbon atom may be substituted with a substituent selected from a halogen atom and an alkyl group having 1 to 8 carbon atoms. ]
It is 1 or more types selected from the group of the tetravalent group represented by either.

  In R2 (tetravalent group) represented by the above formula, a tetravalent group having an aromatic ring is preferable, and a tetravalent group having two or more aromatic rings is more preferable.

[Wherein, A is an oxygen atom, a sulfur atom, CO, SO, SO ₂ , CH ₂ , CH (CH ₃ ), C (CH ₃ ) ₂ , C (CF ₃ ) ₂ , or C (CCl ₃ ) ₂ Represents. In the formula, a hydrogen atom bonded to a carbon atom may be substituted with a substituent selected from a halogen atom and an alkyl group having 1 to 8 carbon atoms. ]
The tetravalent group represented by these is most preferable.

  A is preferably CO.

  The hydrogen atom bonded to the carbon atom in the above formula (that is, the hydrogen atom bonded to the carbon atom in the tetravalent group which is R2) is a substituent selected from a halogen atom and an alkyl group having 1 to 8 carbon atoms. May be substituted. The hydrogen atom is preferably not substituted.

The above-mentioned thing is mentioned as a halogen atom.
The alkyl group may be linear or branched. Examples of the alkyl group having 1 to 8 carbon atoms include methyl group, ethyl group, propyl group, isopropyl group, butyl group, isobutyl group, sec-butyl group, tert-butyl group, pentyl group, isopentyl group, neopentyl group, Examples include 1-ethylpropyl group, hexyl group, isohexyl group, 1,1-dimethylbutyl group, 2,2-dimethylbutyl group, 3,3-dimethylbutyl group, 2-ethylbutyl group, heptyl group, and octyl group.

  R3 is preferably represented by the following formula:

[Wherein, the hydrogen atom bonded to the carbon atom may be substituted with a substituent selected from a halogen atom and an alkyl group having 1 to 8 carbon atoms. ]
It is 1 or more types selected from the group of the bivalent group represented by either. In addition, the terminal of the said formula shows a bond position instead of a methyl group. For example, the last of the above formula represents a hexamethylene group, not octane.

  The hydrogen atom bonded to the carbon atom in the above formula (that is, the hydrogen atom bonded to the carbon atom in the divalent group represented by R3) is a substituent selected from a halogen atom and an alkyl group having 1 to 8 carbon atoms. (Preferably an alkyl group having 1 to 8 carbon atoms, more preferably an alkyl group having 1 to 6 carbon atoms, and most preferably a methyl group).

  The above-mentioned thing is mentioned as a halogen atom and a C1-C8 alkyl group. Examples of the alkyl group having 1 to 6 carbon atoms include methyl group, ethyl group, propyl group, isopropyl group, butyl group, isobutyl group, sec-butyl group, tert-butyl group, pentyl group, isopentyl group, neopentyl group, Examples include 1-ethylpropyl group, hexyl group, isohexyl group, 1,1-dimethylbutyl group, 2,2-dimethylbutyl group, 3,3-dimethylbutyl group, and 2-ethylbutyl group.

  In R3 (divalent group) represented by the above formula, a divalent group having an aromatic ring or an alicyclic ring is preferable, and a divalent organic group having an alicyclic ring is more preferable. In the case of a divalent group having an aromatic ring, the following formula:

[Wherein, the hydrogen atom bonded to the carbon atom may be substituted with an alkyl group having 1 to 8 carbon atoms (preferably an alkyl group having 1 to 6 carbon atoms, more preferably a methyl group). ]
Is preferable, and a 4-methyl-1,3-phenylene group (that is, a residue excluding an isocyanate group of toluene-2,4-diisocyanate) is particularly preferable.

  The number average molecular weight of the polyimide resin as the component (A) is preferably 5,000 or more, more preferably 7,000 or more, from the viewpoint of the viscosity of the resin composition and the miscibility of the component (A) with the resin composition. More preferably, it is 9,000 or more, preferably 25,000 or less, more preferably 20,000 or less, and further preferably 15,000 or less.

  From the viewpoint of imparting sufficient flexibility to the cured product of the resin composition, the glass transition temperature of the polyimide resin as the component (A) is preferably 30 ° C. or lower, more preferably −15 ° C. to 29 ° C., and further preferably. Is −10 ° C. to 20 ° C. Here, the glass transition temperature of the polyimide resin can be read from a tan δ peak temperature obtained by dynamic viscoelasticity measurement or thermomechanical analysis by a tensile load method using a thermomechanical analyzer.

  The polyimide resin which is a component (A) can be manufactured as follows, for example. First, the polycarbonate diol as the raw material (a) and the diisocyanate compound as the raw material (b) are reacted at a ratio in which the amount of the isocyanate group of the diisocyanate compound exceeds 1 mol relative to 1 mol of the hydroxy group of the polycarbonate diol. -B):

[Wherein, R1 and R3 have the same meanings as described above, and n represents an integer. ]
The diisocyanate reaction product represented by the formula (hereinafter sometimes abbreviated as “diisocyanate reaction product (ab)”) is produced. n is, for example, an integer of 1 to 100, preferably an integer of 1 to 10.

  These are preferably reacted in such an amount that the molar ratio of the hydroxy group of the polycarbonate diol as the raw material (a): the isocyanate group of the diisocyanate compound as the raw material (b) is 1: 1.5 to 1: 2.5. .

  The reaction between the polycarbonate diol as the raw material (a) and the diisocyanate compound as the raw material (b) is usually performed in an organic solvent at a temperature of 80 ° C. or lower for 1 to 8 hours. In this reaction, a catalyst may be used if necessary.

  Examples of the organic solvent include N, N′-dimethylformamide, N, N′-diethylformamide, N, N′-dimethylacetamide, N, N′-diethylacetamide, dimethyl sulfoxide, diethyl sulfoxide, N-methyl- Examples include polar solvents such as 2-pyrrolidone, tetramethylurea, γ-butyrolactone, cyclohexanone, diglyme, triglyme, diethylene glycol monoethyl ether acetate, propylene glycol monomethyl ether acetate, and propylene glycol monoethyl ether acetate. These polar solvents may use only 1 type and may use 2 or more types together. Further, if necessary, nonpolar solvents such as aromatic hydrocarbons may be appropriately mixed and used.

  Examples of the catalyst include organometallic catalysts such as dibutyltin dilaurate, dimethyltin dichloride, cobalt naphthenate, and zinc naphthenate.

Next, the polyisocyanate which is the raw material (c) or its anhydride is reacted with the obtained diisocyanate reactant (ab). The reaction rate of the polybasic acid or its anhydride is not particularly limited, but in order to prevent the isocyanate group from remaining in the polyimide resin as the component (A) as much as possible, the molar amount of the isocyanate group contained in the raw material (b) is set. X, the molar amount of hydroxy groups contained in the raw material (a) W, when the molar amount of carboxyl groups contained in the raw material (c) to the molar amount of Y ₁ and acid anhydride group and Y _2, 0.5Y ₁ It is preferable to carry out the reaction in an amount satisfying the relationship of + Y ₂ > X−W ≧ (0.5Y ₁ + Y ₂ ) / 5.

  The reaction of the diisocyanate reactant (ab) with the polybasic acid or its anhydride as the raw material (c) is usually carried out at a temperature of 120 to 180 ° C. for 2 to 24 hours. In this reaction, a catalyst may be used if necessary. Further, the reaction may be carried out after further adding the above-mentioned organic solvent.

  Examples of the catalyst include amines such as tetramethylbutanediamine, benzyldimethylamine, triethanolamine, triethylamine, N, N′-dimethylpiperidine, α-methylbenzyldimethylamine, N-methylmorpholine, and triethylenediamine. It is done. Of these, triethylenediamine is preferred.

  The polyimide resin which is a component (A) can be manufactured as mentioned above. As the component (A), the formula (abc):

[Wherein, R1 to R3 have the same meanings as described above, and n and m represent integers. ]
A polyimide resin having a structure represented by is more preferable. n is an integer of, for example, 1 to 100, preferably an integer of 1 to 10, and m is an integer of, for example, 1 to 100, preferably an integer of 1 to 10.

  In the reaction described above, it is preferable to confirm the disappearance of the isocyanate group by FT-IR or the like in order to keep the isocyanate group (—NCO) in the polyimide resin as the component (A) as much as possible. The end of the polyimide resin thus obtained is represented by formula (1-d) or formula (1-e):

[In each formula, R2 is as defined above. ]
Can be expressed as

In the production of the component (A) polyimide resin, after reacting the diisocyanate reactant (ab) with the polybasic acid or anhydride thereof as the raw material (c), the resulting reactant is further mixed with a diisocyanate compound. A higher molecular weight polyimide resin can be produced by reacting with. The reaction ratio of the isocyanate compound in this case is not particularly limited, but the molar amount of the isocyanate group contained in the raw material (b) is X, the molar amount of the hydroxy group contained in the raw material (a) is W, and the raw material (c) is contained. Assuming that the molar amount of the carboxy group is Y ₁ , the molar amount of the acid anhydride group is Y ₂ , and the molar amount of the isocyanate group contained in the diisocyanate compound to be further reacted is Z, (0.5Y ₁ + Y ₂ ) − (X It is preferable to carry out the reaction in an amount satisfying the relationship of −W)> Z ≧ 0.

  The above reaction with a further diisocyanate compound is usually carried out at a temperature of 120 to 180 ° C. for 2 to 24 hours.

  In order to remove insoluble matter from the reaction solution containing the polyimide resin, filtration may be performed as necessary. Thus, the polyimide resin which is a component (A) can be obtained in a varnish form. The amount of solvent in the polyimide resin varnish can be appropriately adjusted by adjusting the amount of solvent during the reaction, or adding or removing the solvent after the reaction.

  The acid value of the polyimide resin is preferably 3 to 30 mgKOH / g, and more preferably 5 to 20 mKOH / g. The viscosity of the polyimide resin is preferably 3 to 15 Pa · s, more preferably 5 to 10 Pa · s at a solid content of 50 wt%.

<(B) Thermosetting resin>
Component (B) is one or more thermosets selected from epoxy resins, bismaleimide resins, cyanate ester resins, bisallyl nadiimide resins, vinyl benzyl ether resins, benzoxazine resins, and polymers of bismaleimides and diamines. Resin. Only one of these may be used, or two or more may be used in combination.

  In the present invention, the epoxy resin means a thermosetting resin having two or more epoxy groups in one molecule and having an epoxy equivalent of 80 to 8000. Only one type of epoxy resin may be used, or two or more types may be used in combination. In addition, the phenoxy resin which can have an epoxy group like an epoxy resin means the thermoplastic resin in which an epoxy equivalent exceeds 8000 in this invention, and is distinguished from an epoxy resin. The epoxy equivalent of the epoxy resin is preferably 90 to 500, more preferably 90 to 300, and still more preferably 110 to 250.

  Examples of the epoxy resin include bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, bisphenol AF type epoxy resin, phenol novolac type epoxy resin, tert-butyl-catechol type epoxy resin, and naphthalene type epoxy resin. Naphthylene ether type epoxy resin, glycidylamine type epoxy resin, glycidyl ester type epoxy resin, cresol novolac type epoxy resin, biphenyl type epoxy resin, anthracene type epoxy resin, linear aliphatic epoxy resin, epoxy resin having butadiene structure, Alicyclic epoxy resin, heterocyclic epoxy resin, spiro ring-containing epoxy resin, cyclohexanedimethanol type epoxy resin, trimethylol type epoxy resin, halogenated epoxy resin Carboxymethyl resins. Among these, an epoxy resin having an aromatic ring is preferable, and at least one selected from the group consisting of bisphenol A type epoxy resin, bisphenol F type epoxy resin and naphthalene type epoxy resin is more preferable, and bisphenol A type epoxy resin and naphthalene type are preferable. More preferred is at least one selected from the group consisting of epoxy resins.

  When using an epoxy resin, an epoxy curing agent may be used. Examples of the epoxy curing agent include amine-based curing agents, guanidine-based curing agents, imidazole-based curing agents, phenol-based curing agents, acid anhydride-based curing agents, or epoxy adducts or microencapsulated ones thereof. Can do. In particular, amine-based curing agents and imidazole-based curing agents are preferred from the viewpoint of viscosity stability when the thermosetting resin composition is made into a varnish. Only one type of epoxy curing agent may be used, or two or more types may be used in combination.

  Examples of the bismaleimide resin include “BMI-S” (Mitsui Chemical Co., Ltd.), which is 4,4′-phenylmethane bismaleimide, and “BMI-M-20” (Mitsui Chemicals, Inc.), which is polyphenylmethane maleimide. Etc.). Bismaleimide resin may use only 1 type and may use 2 or more types together.

  Although there is no restriction | limiting in particular as cyanate ester resin, Novolac type (phenol novolak type, alkylphenol novolak type, etc.) cyanate ester resin, dicyclopentadiene type cyanate ester resin, bisphenol type (bisphenol A type, bisphenol F type, bisphenol S type) And the like) and cyanate ester resins, and prepolymers in which these are partially triazines. Specific examples of the cyanate ester resin include bisphenol A dicyanate, polyphenol cyanate (oligo (3-methylene-1,5-phenylene cyanate), 4,4′-methylenebis (2,6-dimethylphenyl cyanate), 4,4 ′. -Ethylidene diphenyl dicyanate, hexafluorobisphenol A dicyanate, 2,2-bis (4-cyanate) phenylpropane, 1,1-bis (4-cyanatephenylmethane), bis (4-cyanate-3,5-dimethylphenyl) ) Bifunctional cyanate resins such as methane, 1,3-bis (4-cyanatephenyl-1- (methylethylidene)) benzene, bis (4-cyanatephenyl) thioether, bis (4-cyanatephenyl) ether, phenol novolac, Cresolno Examples thereof include polyfunctional cyanate resins derived from racks, dicyclopentadiene structure-containing phenol resins, etc., prepolymers in which these cyanate resins are partially triazines, etc. These may be used alone or in combination of two or more. Examples of commercially available cyanate ester resins include dicyclopentadiene structure-containing cyanate ester resins (DT-4000, DT-7000, manufactured by Lonza Japan Co., Ltd.), “primerset ( “Primaset BA200” (manufactured by Lonza), “Primaset BA230S” (manufactured by Lonza), “Primaset LECY” (Lonza) which is a bisphenol H-type cyanate ester resin. ), “Arocy L10” (manufactured by Bantico), “Primaset PT30” (manufactured by Lonza), which is a novolak cyanate ester resin, “Arocy XU371” (Bantico ( Co., Ltd.), “Arocy XP71787.02L” (Bantico Co., Ltd.) which is a dicyclopentadiene-type cyanate ester resin, etc. Only one type of cyanate ester resin may be used, Two or more kinds may be used in combination.

  Examples of the bisallylnadiimide resin include “BANI-M” (manufactured by Maruzen Petrochemical Co., Ltd.), which is diphenylmethane-4,4′-bisallylnadicimide. A bisallyl nadiimide resin may use only 1 type and may use 2 or more types together.

  Examples of the vinyl benzyl ether resin include V-1000X (manufactured by Showa Polymer Co., Ltd.), US Pat. No. 4,116,936, US Pat. No. 4,170,711, US Pat. No. 4,278,708, and JP-A-9-31006. No. 1, JP-A No. 2001-181383, JP-A No. 2001-253992, JP-A No. 2003-277440, JP-A No. 2003-283076, WO 02/083610, and the like. . Only 1 type may be used for a vinyl benzyl ether resin, and it may use 2 or more types together.

  Examples of the benzoxazine resin include “Ba type benzoxazine” and “Bm type benzoxazine” manufactured by Shikoku Kasei Co., Ltd. Only one type of benzoxazine resin may be used, or two or more types may be used in combination.

  Examples of the polymer of the bismaleimide compound and the diamine compound which are thermosetting resins include “Techmite E2020” manufactured by Printec Co., Ltd. As the polymer of the bismaleimide compound and the diamine compound, only one type may be used, or two or more types may be used in combination.

  As a thermosetting resin which is a component (B), an epoxy resin is preferable and a liquid epoxy resin is more preferable. Here, the liquid epoxy resin means an epoxy resin that is liquid at 25 ° C. The liquid epoxy resin is preferably a liquid epoxy resin having an aromatic ring, more preferably at least one selected from the group consisting of a liquid bisphenol A type epoxy resin, a liquid bisphenol F type epoxy resin and a liquid naphthalene type epoxy resin. More preferred is at least one selected from the group consisting of type epoxy resins and liquid naphthalene type epoxy resins.

  The content of the thermosetting resin as the component (B) is preferably 15 to 100 parts by weight of the polyimide resin as the component (A) from the viewpoint of the degree of cure of the resin composition and the flexibility of the cured product. 80 parts by weight, more preferably 30 to 80 parts by weight, still more preferably 40 to 70 parts by weight.

  The total amount of component (A) and component (B) is determined based on the non-volatile content of the thermosetting resin composition in consideration of the chemical resistance of the cured product and the relationship with other components in the thermosetting resin composition. The content is preferably 5 to 50% by weight, more preferably 10 to 30% by weight. Here, the nonvolatile content of the thermosetting resin composition means the total of the remaining components excluding the volatile solvent from the thermosetting resin composition.

<Inorganic filler>
The thermosetting resin composition of the present invention may further contain one or more inorganic fillers. By using an inorganic filler, the linear thermal expansion coefficient of the insulating layer obtained from a thermosetting resin composition can be reduced. Examples of the inorganic filler include silica, alumina, barium sulfate, talc, clay, mica powder, aluminum hydroxide, magnesium hydroxide, calcium carbonate, magnesium carbonate, magnesium oxide, boron nitride, aluminum borate, barium titanate, Examples include strontium titanate, calcium titanate, magnesium titanate, bismuth titanate, titanium oxide, barium zirconate, and calcium zirconate. Among them, amorphous silica, pulverized silica, fused silica, crystalline silica, synthetic silica, hollow silica, spherical silica, and the like are preferable, and fused silica and spherical silica are more preferable from the viewpoint of enhancing the filling property, and spherical fused silica is more preferable. preferable. Examples of commercially available spherical fused silica include “SO-C2” and “SO-C1” manufactured by Admatechs.

  The average particle diameter of the inorganic filler is not particularly limited, but the viewpoint that it is necessary to reduce the roughness to enable fine wiring formation after the roughening treatment of the insulating layer surface, and the via shape by laser processing is good From the viewpoint of becoming, it is preferably 5 μm or less, more preferably 3 μm or less, further preferably 2 μm or less, still more preferably 1 μm or less, particularly preferably 0.8 μm or less, and particularly preferably 0.6 μm or less. On the other hand, when the thermosetting resin composition is used as a varnish, the average particle size is preferably 0.01 μm or more from the viewpoint of preventing the viscosity of the varnish from increasing and handling properties from being lowered. It is more preferably 03 μm or more, more preferably 0.05 μm or more, still more preferably 0.07 μm or more, and particularly preferably 0.1 μm or more. 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 size distribution of the inorganic filler can be prepared on a volume basis by a laser diffraction / scattering particle size distribution measuring apparatus, and the median diameter can be measured as the average particle diameter. As the measurement sample, an inorganic filler dispersed in water by ultrasonic waves can be preferably used. As a laser diffraction scattering type particle size distribution measuring apparatus, LA-950 manufactured by Horiba, Ltd. or the like can be used.

  In order to reduce the linear thermal expansion coefficient of the insulating layer (cured material) obtained from the thermosetting resin composition, the content of the inorganic filler is preferably 50% by weight or more in the nonvolatile content of the thermosetting resin composition. More preferably, it is 60% by weight or more, more preferably 70% by weight or more, and particularly preferably 80% by weight or more. On the other hand, in terms of preventing the insulating layer from becoming brittle, and from the point of reducing the roughness of the insulating layer surface after the roughening treatment, in the nonvolatile content of the thermosetting resin composition, preferably 95% by weight or less, More preferably, it is 93 weight% or less, More preferably, it is 90 weight% or less, Most preferably, it is 85 weight% or less.

  As the inorganic filler, it is preferable to use an inorganic filler surface-treated with one or more surface treatment agents. Examples of the surface treatment agent include amino silane coupling agents, epoxy silane coupling agents, mercapto silane coupling agents, styryl silane coupling agents, acrylate silane coupling agents, isocyanate silane coupling agents, and sulfides. Examples include silane coupling agents, vinyl silane coupling agents, silane coupling agents, organosilazane compounds, and titanate coupling agents. By the surface treatment, the dispersibility and moisture resistance of the inorganic filler can be improved.

  Specific surface treatment agents include 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-aminopropyldiethoxymethylsilane, N-phenyl-3-aminopropyltrimethoxysilane, and N-methylamino. Aminosilane coupling agents such as propyltrimethoxysilane, N-2 (-aminoethyl) -3-aminopropyltrimethoxysilane, N- (2-aminoethyl) -3-aminopropyldimethoxymethylsilane; 3-glycidyloxy Propyltrimethoxysilane, 3-glycidyloxypropyltriethoxysilane, 3-glycidyloxypropylmethyldiethoxysilane, 3-glycidyloxypropyl (dimethoxy) methylsilane, glycidylbutyltrimethoxysilane, 2- (3,4-epoxy (Cyclohexyl) Epoxysilane coupling agents such as ethyltrimethoxysilane; mercapto such as 3-mercaptopropyltrimethoxysilane, 3-mercaptopropyltriethoxysilane, 3-mercaptopropylmethyldimethoxysilane, 11-mercaptoundecyltrimethoxysilane Silane coupling agents; styrylsilane coupling agents such as p-styryltrimethoxysilane; 3-acryloxypropyltrimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropyldimethoxysilane, 3-methacryl Acrylate silane coupling agents such as oxypropyltriethoxysilane and 3-methacryloxypropyldiethoxysilane; 3-isocyanatopropyltrimethoxy Isocyanate silane coupling agents such as run; sulfide silane coupling agents such as bis (triethoxysilylpropyl) disulfide and bis (triethoxysilylpropyl) tetrasulfide; methyltrimethoxysilane, octadecyltrimethoxysilane, phenyltrimethoxy Silane coupling agents such as silane, methacryloxypropyltrimethoxysilane, imidazolesilane, triazinesilane, t-butyltrimethoxysilane; hexamethyldisilazane, 1,3-divinyl-1,1,3,3-tetramethyl Disilazane, hexaphenyldisilazane, trisilazane, cyclotrisilazane, octamethylcyclotetrasilazane, hexabutyldisilazane, hexaoctyldisilazane, 1,3-diethyltetramethyldisilazane 1,3-di-n-octyltetramethyldisilazane, 1,3-diphenyltetramethyldisilazane, 1,3-dimethyltetraphenyldisilazane, 1,3-diethyltetramethyldisilazane, 1,1,3 Organosilazane compounds such as 1,3-tetraphenyl-1,3-dimethyldisilazane, 1,3-dipropyltetramethyldisilazane, hexamethylcyclotrisilazane, dimethylaminotrimethylsilazane, tetramethyldisilazane; tetra-n- Butyl titanate dimer, titanium-i-propoxyoctylene glycolate, tetra-n-butyl titanate, titanium octylene glycolate, diisopropoxytitanium bis (triethanolaminate), dihydroxytitanium bislactate, dihydroxybis (ammonium lactate) G) Titanium, bis (dioctyl pyrophosphate) ethylene titanate, bis (dioctyl pyrophosphate) oxyacetate titanate, tri-n-butoxytitanium monostearate, tetra-n-butyl titanate, tetra (2-ethylhexyl) titanate, tetraisopropyl Bis (dioctyl phosphite) titanate, tetraoctyl bis (ditridecyl phosphite) titanate, tetra (2,2-diallyloxymethyl-1-butyl) bis (ditridecyl) phosphite titanate, isopropyl trioctanoyl titanate, isopropyl tricumyl Phenyl titanate, isopropyl triisostearoyl titanate, isopropyl isostearoyl diacryl titanate, isopropyl dimethacryliso And titanate coupling agents such as theaeroyl titanate, isopropyl tri (dioctyl phosphate) titanate, isopropyl tridodecylbenzenesulfonyl titanate, isopropyl tris (dioctyl pyrophosphate) titanate, isopropyl tri (N-amidoethyl / aminoethyl) titanate . Of these, aminosilane coupling agents, epoxysilane coupling agents, mercaptosilane coupling agents, and organosilazane compounds are preferred, and aminosilane coupling agents are more preferred. Commercially available products include “KBM403” (3-glycidoxypropyltrimethoxysilane) manufactured by Shin-Etsu Chemical Co., Ltd., “KBM803” (3-mercaptopropyltrimethoxysilane) manufactured by Shin-Etsu Chemical Co., Ltd., Shin-Etsu Chemical Co., Ltd. "KBE903" (3-aminopropyltriethoxysilane) manufactured by Co., Ltd., "KBM573" (N-phenyl-3-aminopropyltrimethoxysilane) manufactured by Shin-Etsu Chemical Co., Ltd., "SZ" manufactured by Shin-Etsu Chemical Co., Ltd. -31 "(hexamethyldisilazane) and the like.

  The surface treatment method of the inorganic filler with the surface treatment agent is not particularly limited, and examples thereof include a dry method and a wet method. As a dry method, for example, an inorganic filler is charged in a rotary mixer, and an alcohol solution or an aqueous solution of a surface treatment agent is dropped or sprayed while stirring, followed by further stirring, classification with a sieve, and then surface treatment by heating. And a method of dehydrating and condensing the agent and the inorganic filler. As a wet method, for example, a surface treatment agent is added while stirring a slurry of an inorganic filler and an organic solvent, and after stirring, classification is performed by filtration, drying and sieving, and then the surface treatment agent and the inorganic solvent are heated. The method of dehydrating and condensing with a filler is mentioned. Furthermore, the surface treatment of the inorganic filler can also be performed by an integral blend method in which a surface treatment agent is added to the thermosetting resin composition.

<Curing accelerator>
The thermosetting resin composition of the present invention may further contain one or more curing accelerators. The thermosetting resin that is the component (B) can be efficiently cured by the curing accelerator. Although it does not specifically limit as a hardening accelerator, An imidazole type hardening accelerator, an amine type hardening accelerator, a guanidine type hardening accelerator, a phosphonium type hardening accelerator etc. are mentioned.

  Examples of the imidazole curing accelerator include 2-methylimidazole, 2-undecylimidazole, 2-heptadecylimidazole, 1,2-dimethylimidazole, 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 Phenylimidazolium 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-triazine isocyanuric acid adduct, 2-phenylimidazole isocyanuric acid adduct, 2-phenyl-4,5-dihydroxymethylimidazole, 2-phenyl- 4-methyl-5-hydroxymethylimidazole, 2,3-dihydro-1H-pyrrolo [1,2-a] benzimidazole, 1-dodecyl-2-methyl 3-benzyl-imidazolium chloride, 2-methyl-imidazoline, 2-phenyl-imidazoline, etc. imidazole compounds of and imidazole compounds and adducts such as with epoxy resin. Only 1 type may be used for an imidazole-type hardening accelerator, and 2 or more types may be used together.

  Examples of amine curing accelerators include trialkylamines such as triethylamine and tributylamine, 4-dimethylaminopyridine, benzyldimethylamine, 2,4,6, -tris (dimethylaminomethyl) phenol, 1,8-diazabicyclo. And amine compounds such as [5.4.0] -undecene (DBU). Only 1 type may be used for an amine hardening accelerator, and 2 or more types may be used together.

  Examples of the guanidine curing accelerator include dicyandiamide, 1-methylguanidine, 1-ethylguanidine, 1-cyclohexylguanidine, 1-phenylguanidine, 1- (o-tolyl) guanidine, dimethylguanidine, diphenylguanidine, trimethylguanidine, Tetramethylguanidine, pentamethylguanidine, 1,5,7-triazabicyclo [4.4.0] dec-5-ene, 7-methyl-1,5,7-triazabicyclo [4.4.0] Deca-5-ene, 1-methyl biguanide, 1-ethyl biguanide, 1-n-butyl biguanide, 1-n-octadecyl biguanide, 1,1-dimethyl biguanide, 1,1-diethyl biguanide, 1-cyclohexyl biguanide, 1 -Allyl biguanide, 1-phenyl biguanide, 1- ( - tolyl) biguanide, and the like. A guanidine type hardening accelerator may use only 1 type, and may use 2 or more types together.

  Examples of the phosphonium curing accelerator include triphenylphosphine, phosphonium borate compound, tetraphenylphosphonium tetraphenylborate, n-butylphosphonium tetraphenylborate, tetrabutylphosphonium decanoate, (4-methylphenyl) triphenylphosphonium thiocyanate. , Tetraphenylphosphonium thiocyanate, butyltriphenylphosphonium thiocyanate, and the like. Only one type of phosphonium-based curing accelerator may be used, or two or more types may be used in combination.

  When using a hardening accelerator, the content thereof is preferably 0.5 to 5 parts by weight, more preferably 1 to 3 parts by weight with respect to 100 parts by weight of the thermosetting resin as the component (B). .

<Other ingredients>
The thermosetting resin composition of the present invention can contain other components as necessary within a range not inhibiting the effects of the present invention. Examples of other components include organic fillers such as silicone powder, nylon powder, fluorine powder, and rubber particles; thickeners such as olben and benton; silicone-based, fluorine-based, and polymer-based antifoaming agents or leveling agents. Adhesion imparting agents such as thiazole silane coupling agents and triazole silane coupling agents; Colorants such as phthalocyanine blue, phthalocyanine green, iodin green, disazo yellow, carbon black; organic phosphorus flame retardants, organic Flame retardants such as nitrogen-containing phosphorus compounds, nitrogen compounds, silicone flame retardants, metal hydroxides, and the like.

  The thermosetting resin composition of the present invention is appropriately mixed with the above components, and if necessary, by kneading means such as a triple roll, ball mill, bead mill, sand mill, or stirring means such as a super mixer or planetary mixer. It can be prepared by kneading or mixing. Further, it can be prepared as a resin varnish by further adding a solvent.

  Examples of the solvent that can be used in the thermosetting resin composition (resin varnish) include ketones such as acetone, methyl ethyl ketone, and cyclohexanone; ethyl acetate, butyl acetate, cellosolve acetate, propylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether Examples thereof include esters such as acetate; ethers such as cellosolve and butyl carbitol; aromatic hydrocarbons such as toluene and xylene; amide solvents such as dimethylformamide, dimethylacetamide and N-methylpyrrolidone. Only 1 type may be used for a solvent and it may use 2 or more types together. Among these, ketones and esters are preferable, and diethylene glycol monoethyl ether acetate and methyl ethyl ketone are preferable.

  When using a solvent, the content is preferably 10 to 50% by weight, more preferably 20 to 40% by weight in the thermosetting resin composition from the viewpoint of the viscosity of the thermosetting resin composition (resin varnish). %.

  A cured product formed from the thermosetting resin composition of the present invention is suitable as an insulating layer of a circuit board. The insulating layer may be formed by applying a thermosetting resin composition in the form of a resin varnish to a substrate, and an adhesive film having a layer formed from the thermosetting resin composition on a support is used. May be formed.

<Adhesive film>
This invention provides the adhesive film which has the layer formed from the above-mentioned thermosetting resin composition on a support body. The adhesive film of the present invention is applied to a support using a method known to those skilled in the art, for example, a resin varnish in which a thermosetting resin composition is dissolved in a solvent, using a die coater or the like, and further heated or blown with hot air. It can be produced by removing the solvent by attaching or the like and forming a thermosetting resin composition layer on the support.

  The solvent is removed so that the content (residual solvent amount) of the solvent in the thermosetting resin composition layer is usually 10% by weight or less, preferably 6% by weight or less. The conditions for solvent removal (drying) vary depending on the amount of solvent in the resin varnish and the boiling point of the solvent. For example, when a resin varnish containing 30 to 60% by weight of solvent is used, it is usually 3 to 10 at 50 to 150 ° C. About minutes.

  The thickness (thickness after drying) of the thermosetting resin composition layer formed in the adhesive film is preferably not less than the thickness of the conductor layer. Since the thickness of the conductor layer of the circuit board is usually in the range of 5 to 70 μm, the thickness of the thermosetting resin composition layer is preferably 10 to 200 μm, more preferably 15 to 100 μm from the viewpoint of thinning. 20-60 micrometers is still more preferable.

  Examples of the support include polyolefin films such as polyethylene, polypropylene, and polyvinyl chloride, polyethylene terephthalate (hereinafter sometimes abbreviated as “PET”), polyester films such as polyethylene naphthalate, polycarbonate films, and polyimide films. Various plastic films are listed. Release paper; metal foil such as copper foil and aluminum foil may be used. Among these, from the viewpoint of versatility, a plastic film is preferable, and a PET film is more preferable. The support and the protective film described later may be subjected to surface treatment such as mud treatment and corona treatment, and release agents such as silicone resin release agents, alkyd resin release agents, fluororesin release agents, etc. The mold may be released from the mold. Although the thickness of a support body is not specifically limited, 10-150 micrometers is preferable and 25-50 micrometers is more preferable.

  A protective film according to the support can be further laminated on the surface of the thermosetting resin composition layer on which the support is not in close contact. Although the thickness of a protective film is not specifically limited, For example, it is 1-40 micrometers, Preferably it is 5-20 micrometers. By laminating the protective film, it is possible to prevent dust and the like from being attached to the surface of the thermosetting resin composition layer and scratches. The adhesive film can also be stored in a roll.

<Printed wiring board>
This invention provides the printed wiring board which has the hardened | cured material formed from the above-mentioned thermosetting resin composition as an insulating layer. Examples of the printed wiring board of the present invention include a rigid circuit board, a flexible circuit board, a single area layer board, and a thin board. Among these, a flexible circuit board is preferable. An example of a method for producing a printed wiring board using the adhesive film produced as described above will be described.

  First, an adhesive film is laminated (laminated) on one or both sides of the inner circuit board using a vacuum laminator. Examples of the substrate used for the inner circuit board include a glass epoxy substrate, a metal substrate, a polyester substrate, a polyimide substrate, a BT resin substrate, and a thermosetting polyphenylene ether substrate. In addition, an inner layer circuit board means here that the conductor layer (circuit) by which the pattern process was carried out on the one or both surfaces of the above boards was formed. Also, in a multilayer printed wiring board in which conductor layers and insulating layers are alternately laminated, a conductor layer (circuit) in which one or both surfaces of the outermost layer of the multilayer printed wiring board is patterned is used here. It is included in the inner layer circuit board. The surface of the conductor layer may be previously roughened by blackening, copper etching, or the like.

In the above laminate, when the adhesive film has a protective film, after removing the protective film, the adhesive film and the circuit board are preheated as necessary, and the adhesive film is pressurized and heated to the circuit board. Laminate. In the adhesive film of the present invention, a method of laminating on a circuit board under reduced pressure by a vacuum laminating method is preferably used. Lamination conditions are not particularly limited. For example, the pressure bonding temperature (laminating temperature) is preferably 70 to 140 ° C., and the pressure bonding pressure (laminating pressure) is preferably 1 to 11 kgf / cm ² (9.8 × 10 ^{4 to} 107.9 × 10 ⁴ N / m ² ), the pressure bonding time (laminating time) is preferably 5 to 180 seconds, and the lamination is preferably performed under reduced pressure with an air pressure of 20 mmHg (26.7 hPa) or less. The laminating method may be a batch method or a continuous method using a roll. The vacuum lamination can be performed using a commercially available vacuum laminator. Commercially available vacuum laminators include, for example, a vacuum applicator manufactured by Nichigo-Morton Co., Ltd., a vacuum pressurizing laminator manufactured by Meiki Seisakusho Co., Ltd., a roll dry coater manufactured by Hitachi Industries, Ltd., Hitachi AIC Co., Ltd. ) Made vacuum laminator and the like.

  After laminating the adhesive film to the inner layer circuit board, after cooling to near room temperature, if the support is peeled off, it is peeled off, and the thermosetting resin composition is thermoset to form a cured product, thereby forming the inner layer circuit. An insulating layer can be formed over the substrate. The thermosetting conditions may be appropriately selected according to the type and content of the resin component in the thermosetting resin composition, but preferably at 150 to 220 ° C. for 20 to 180 minutes, more preferably 160 to 210. It is selected in the range of 30 to 120 minutes at ° C. After forming the insulating layer (cured product), if the support is not peeled off before curing, it can be peeled off if necessary. As with the thickness of the thermosetting resin composition layer formed in the adhesive film, the thickness of the insulating layer is preferably 10 to 200 μm, more preferably 15 to 100 μm from the viewpoint of thinning, and further preferably 20 to 60 μm. .

  Next, a hole is formed in the insulating layer formed on the inner layer circuit board to form a via hole and a through hole. For example, the drilling can be performed by a known method such as drilling, laser, or plasma, or a combination of these methods if necessary, but drilling by a laser such as a carbon dioxide gas laser or a YAG laser is the most common. Is the method. If the support is not peeled off before drilling, it will be peeled off here.

  Next, a roughening process is performed on the surface of the insulating layer. In the case of dry-type roughening treatment, plasma treatment or the like is mentioned. In the case of wet-type roughening treatment, a method of performing swelling treatment with a swelling liquid, roughening treatment with an oxidizing agent and neutralization treatment with a neutralizing liquid in this order is mentioned. It is done. The wet roughening treatment is preferable in that smear in the via hole can be removed while forming an uneven anchor on the surface of the insulating layer. The swelling treatment with the swelling liquid is performed by immersing the insulating layer in the swelling liquid at 50 to 80 ° C. for 5 to 20 minutes (preferably at 55 to 70 ° C. for 8 to 15 minutes). Examples of the swelling liquid include an alkaline solution and a surfactant solution, and an alkaline solution is preferable. Examples of the alkaline solution include a sodium hydroxide solution and a potassium hydroxide solution. Examples of commercially available swelling liquids include Swelling Dip Securigans P (Swelling Dip Securigans SBU) and Swelling Dip Securigans SBU manufactured by Atotech Japan Co., Ltd. be able to. The roughening treatment with an oxidizing agent is performed by immersing the insulating layer in an oxidizing agent solution at 60 to 80 ° C. for 10 to 30 minutes (preferably at 70 to 80 ° C. for 15 to 25 minutes). Examples of the oxidizing agent include alkaline permanganate solution in which potassium permanganate and sodium permanganate are dissolved in an aqueous solution of sodium hydroxide, dichromate, ozone, hydrogen peroxide / sulfuric acid, nitric acid and the like. it can. The concentration of permanganate in the alkaline permanganate solution is preferably 5 to 10% by weight. Examples of commercially available oxidizing agents include alkaline permanganic acid solutions such as Concentrate Compact CP and Dosing Solution Securigans P manufactured by Atotech Japan. The neutralization treatment with the neutralizing solution is performed by immersing in a neutralizing solution at 30 to 50 ° C. for 3 to 10 minutes (preferably at 35 to 45 ° C. for 3 to 8 minutes). As the neutralizing solution, an acidic aqueous solution is preferable, and as a commercially available product, Reduction Solution / Secligant P manufactured by Atotech Japan Co., Ltd. may be mentioned.

  The arithmetic average roughness (Ra) of the surface of the insulating layer after the roughening treatment is preferably 220 to 1000 nm, more preferably 300 to 800 nm, from the viewpoint of forming fine wiring and stabilizing the peel strength. Specifically, using a non-contact type surface roughness meter (WYKO NT3300 manufactured by BEIKO INSTRUMENTS Co., Ltd.), the Ra value can be obtained from a numerical value obtained with a measurement range of 121 μm × 92 μm by a VSI contact mode and a 50 × lens. .

  Next, a conductor layer is formed on the insulating layer by dry plating or wet plating. As the dry plating, a known method such as vapor deposition, sputtering, or ion plating can be used. Examples of wet plating include a method in which a conductive layer is formed by combining electroless plating and electrolytic plating, a method in which a plating resist having a pattern opposite to that of the conductive layer is formed, and a conductive layer is formed only by electroless plating. It is done.

  The peel strength between the conductor layer and the insulating layer is preferably 0.5 kgf / cm or more, more preferably 0.6 kgf / cm or more, and further preferably 0.7 kgf / cm or more. The upper limit of the peel strength is not particularly limited, and is, for example, 1.5 kgf / cm or less, preferably 1.0 kgf / cm or less.

  As a pattern formation method thereafter, for example, a subtractive method or a semi-additive method known to those skilled in the art can be used, and a multilayer in which build-up layers are stacked in multiple stages by repeating the above-described series of steps a plurality of times. A printed wiring board can also be formed.

<Wafer level chip size package>
The present invention provides a wafer level chip size package having a cured product formed from the thermosetting resin composition described above as an insulating layer. The thermosetting resin composition may be laminated on both sides of the wafer level chip size package, or may be laminated on one side. Various structures have been devised for the wafer level chip size package, and can be roughly divided into a fan-in structure and a fan-out structure. The thickness of the silicon wafer is preferably 50 to 150 μm and more preferably 80 to 120 μm from the viewpoint of thinning.

As an example of a method of manufacturing a wafer-level chip size package having a fan-in structure using the adhesive film manufactured as described above, a method including the following steps may be mentioned.
(1) A step of forming circuits and electrode pads on a silicon wafer.
(2) A step of laminating the adhesive film of the present invention on a silicon wafer.
(3) A step of curing the adhesive film, peeling off the support, drilling, performing desmear treatment, and forming a rewiring layer by electroless plating and electrolytic plating.
(4) A step of repeating (2) and (3) from above the rewiring layer as necessary.
(5) A step of forming solder balls on the rewiring layer.
(6) A step of performing dicing.

An example of a method for manufacturing a wafer level chip size package having another fan-in structure is the method described in Japanese Patent No. 3618330. Moreover, as an example, a method including the following steps may be mentioned.
(1) A step of creating a silicon wafer on which a circuit element having a predetermined function and a plurality of electrode pads electrically connected to the circuit element are formed.
(2) A step of forming a columnar electrode on the upper surface of the electrode pad portion on the silicon wafer.
(3) A step of bonding the adhesive film of the present invention from the columnar electrode surface side, curing, peeling the support, and forming an insulating layer.
(4) A step of appropriately polishing and removing the upper surface portion of the insulating layer and the columnar electrode to expose the upper surface of the columnar electrode.
(5) A step of forming a solder ball on the upper surface of the exposed columnar electrode.
(6) A step of performing dicing.

An example of a method for manufacturing a fan-out wafer level chip size package using the adhesive film manufactured as described above includes a method including the following steps.
(1) A step of dicing a silicon wafer to create chip pieces.
(2) A step of fixing the chip pieces on the support substrate through a film.
(3) A step of laminating the adhesive film of the present invention from the chip piece side.
(4) A step of curing the film, peeling off the support, drilling, performing a desmear treatment, and forming a rewiring layer by electroless plating and electrolytic plating.
(5) The process of laminating | stacking a film further as needed.
(6) A step of forming solder balls on the rewiring layer.

As an example of a method for manufacturing a wafer level package having another fan-out structure, there is a method described in JP-A-2005-167191. Moreover, as an example, a method including the following steps may be mentioned.
(1) A step of creating a silicon wafer on which a circuit element having a predetermined function and a plurality of electrode pads electrically connected to the circuit element are formed.
(2) A step of creating semiconductor chip pieces through dicing.
(3) A process of widely arranging and fixing the semiconductor chips via the film on the support in such a positional relationship that the distance between the semiconductor chips has a sufficient space for forming a fan-out ball array in a later step. .
(4) A step of laminating the adhesive film of the present invention so as to fill the space between the semiconductor chips from the surface side on which the semiconductor chips are fixed.
(5) A step of curing the adhesive film, peeling the support, etching the insulating layer on the pad of the semiconductor chip, forming an opening, and forming a conductive layer in the opening.
(6) A step of forming a fan-out pattern and an electrode on the insulating layer using a photoresist and forming a solder ball on the electrode pad.

  Hereinafter, the present invention will be described more specifically with reference to synthesis examples, examples and comparative examples. However, the present invention is not limited by the following synthesis examples and the like, and can be applied to the above and the following purposes. It is of course possible to carry out the invention with appropriate modifications, and these are all included in the technical scope of the present invention. In the following, “%” and “part” mean “% by weight” and “part by weight” unless otherwise specified.

  The equivalent described in the following synthesis examples and the like means a value obtained by dividing the molecular weight of a compound having a functional group, which is the target of equivalent, by the number of functional groups of the compound, that is, the molecular weight per functional group. . For example, the acid anhydride equivalent is a value obtained by dividing the molecular weight of a compound having an acid anhydride group (carbonyloxycarbonyl group) by the number of acid anhydride groups of the compound contained in one molecule, ie, acid anhydride. It means the molecular weight per substance group.

Synthesis Example 1: Production of polyimide resin (A1) Polycarbonate diol (number average molecular weight: about 2,000, hydroxyl group equivalent: 1,000, nonvolatile content: 100%, “C-2015N” manufactured by Kuraray Co., Ltd.) in a reaction vessel 80 g and 0.01 g of dibutyltin dilaurate were uniformly dissolved in 37.6 g of diethylene glycol monoethyl ether acetate (“Ethyl diglycol acetate” manufactured by Daicel Corporation). Next, the mixture was heated to 50 ° C., and further stirred, 13.9 g of toluene-2,4-diisocyanate (isocyanate group equivalent: 87.08) was added, and the reaction was performed for about 3 hours. The reaction was then allowed to cool to room temperature, after which 14.3 g benzophenone tetracarboxylic dianhydride (anhydride equivalent: 161.1), 0.11 g triethylenediamine, and diethylene glycol monoethyl ether acetate (( 70.5 g of “Ethyl Diglycol Acetate” manufactured by Daicel Corporation) was added, the temperature was raised to 130 ° C. with stirring, and the reaction was performed for about 4 hours. The disappearance of the NCO peak at 2250 cm ⁻¹ was confirmed by FT-IR. After confirming the disappearance of the NCO peak, the reaction was regarded as the end point of the reaction, and the reaction product was cooled to room temperature and then filtered through a filter cloth having an opening of 100 μm to obtain a polyimide resin (A1) varnish having an imide structure and a urethane and carbonate structure. Got.

The viscosity and non-volatile content of the obtained polyimide resin (A1) varnish, the number average molecular weight of the polyimide resin (A1), and the glass transition temperature are described below.
Viscosity of polyimide resin (A1) varnish: 6 Pa · s (25 ° C., E-type viscometer)
Nonvolatile content of polyimide resin (A1) varnish: 50%
Number average molecular weight of polyimide resin (A1): 11,500
Glass transition temperature of polyimide resin (A1): -1 ° C

Synthesis Example 2 Production of Polyimide Resin (A2) Polycarbonate diol (number average molecular weight: about 1,000, hydroxyl group equivalent: 500, nonvolatile content: 100%, (“C-1015N” manufactured by Kuraray Co., Ltd.)) 80 g in a reaction vessel And 0.01 g of dibutyltin dilaurate were uniformly dissolved in 37.6 g of diethylene glycol monoethyl ether acetate (“Ethyl Diglycol Acetate” manufactured by Daicel Corporation), and the mixture was heated to 50 ° C. While further stirring, 27.8 g of toluene-2,4-diisocyanate (isocyanate group equivalent: 87.08) was added, and the reaction was carried out for about 3 hours. Benzophenone tetracarboxylic dianhydride (acid anhydride equivalent: 161.1) 14.3 g, triethylenedia 0.12 g of min and 84.0 g of diethylene glycol monoethyl ether acetate (“Ethyl diglycol acetate” manufactured by Daicel Corporation) were added, the temperature was raised to 130 ° C. with stirring, and the reaction was carried out for about 4 hours. The disappearance of the NCO peak at 2250 cm ⁻¹ was confirmed by IR, and the reaction was regarded as the end of the reaction by confirming the disappearance of the NCO peak, and the reaction product was cooled to room temperature and filtered through a filter cloth having an opening of 100 μm. A polyimide resin (A2) varnish having an imide structure and a urethane skeleton and a carbonate structure was obtained.

The viscosity and non-volatile content of the obtained polyimide resin (A2) varnish, the number average molecular weight of the polyimide resin (A2), and the glass transition temperature are described below.
Viscosity of polyimide resin (A2) varnish: 3 Pa · s (25 ° C., E-type viscometer)
Nonvolatile content of polyimide resin (A2) varnish: 50%
Number average molecular weight of polyimide resin (A2): 8,500
Glass transition temperature of polyimide resin (A2): 5 ° C

Example 1
40 parts of liquid bisphenol A type epoxy resin (epoxy equivalent: 180, “jER828EL” manufactured by Mitsubishi Chemical Corporation), 1 part of curing accelerator (imidazole derivative, “2P4MZ” manufactured by Shikoku Kasei Co., Ltd.), polyimide resin (A1) 260 parts of varnish, 300 parts of methyl ethyl ketone (hereinafter abbreviated as “MEK”), 20 parts of liquid naphthalene type epoxy resin (epoxy equivalent: 151, “HP-4032” manufactured by DIC Corporation), and inorganic filler {phenylaminosilane type 920 parts of spherical fused silica (“SO-C2” manufactured by Admatechs Co., Ltd., average particle size: 0.5 μm)} surface-treated with a coupling agent (“KBM573” manufactured by Shin-Etsu Chemical Co., Ltd.) is mixed. The resin varnish was prepared by uniformly dispersing with a high-speed rotary mixer. The composition of the obtained resin varnish (excluding the solvent) is shown in Table 1 below.

Example 2
40 parts of liquid bisphenol A type epoxy resin (epoxy equivalent: 180, “jER828EL” manufactured by Mitsubishi Chemical Corporation), 1 part of curing accelerator (imidazole derivative, “2P4MZ” manufactured by Shikoku Kasei Co., Ltd.), polyimide resin (A2) 260 parts of varnish, 300 parts of MEK, 20 parts of liquid naphthalene type epoxy resin (epoxy equivalent: 151, manufactured by DIC Corporation, HP-4032), and inorganic filler {phenylaminosilane coupling agent (Shin-Etsu Chemical Co., Ltd.) 920 parts of spherical fused silica (manufactured by Admatechs Co., Ltd., “SO-C2”, average particle size: 0.5 μm)} surface-treated with “KBM573” (made by “KBM573”) and uniformly dispersed with a high-speed rotary mixer A resin varnish was prepared. The composition of the obtained resin varnish (excluding the solvent) is shown in Table 1 below.

Comparative Example 1
40 parts of liquid bisphenol A type epoxy resin (epoxy equivalent: 180, “jER828EL” manufactured by Mitsubishi Chemical Corporation), 1 part of curing accelerator (imidazole derivative, “2P4MZ” manufactured by Shikoku Kasei Co., Ltd.), acrylic acid ester 866 parts of polymer (“SG-P3” manufactured by Nagase ChemteX), 300 parts of MEK, 20 parts of liquid naphthalene type epoxy resin (epoxy equivalent: 151, “HP-4032” manufactured by DIC Corporation), and inorganic filler {phenyl 920 parts of spherical fused silica (“SO-C2” manufactured by Admatechs Co., Ltd., average particle size 0.5 μm) surface-treated with an aminosilane coupling agent (“KBM573” manufactured by Shin-Etsu Chemical Co., Ltd.)} The mixture was mixed and dispersed uniformly with a high-speed rotary mixer to prepare a resin varnish. The composition of the obtained resin varnish (excluding the solvent) is shown in Table 1 below.

Comparative Example 2
40 parts of liquid bisphenol A type epoxy resin (epoxy equivalent: 180, "jER828EL" manufactured by Mitsubishi Chemical Corporation), 22 parts of naphthalene type tetrafunctional epoxy resin (epoxy equivalent: 163, "HP-4710" manufactured by DIC Corporation) , 1 part of curing accelerator (imidazole derivative, “2P4MZ” manufactured by Shikoku Kasei Co., Ltd.), phenoxy resin solution (“YX-6554” manufactured by Mitsubishi Chemical Co., Ltd.), mixed solution of MEK and cyclohexanone, nonvolatile content: 30% ) 20 parts, 30 parts of MEK solution (non-volatile content: 50%) of naphthol-based curing agent (hydroxyl equivalent: 215, “SN-485” manufactured by Nippon Steel & Sumikin Co., Ltd.), 30 parts of MEK, and inorganic filler {phenyl Spherical fused silica (Admatech Co., Ltd.) surface-treated with an aminosilane coupling agent ("KBM573" manufactured by Shin-Etsu Chemical Co., Ltd.) Ltd., "SO-C2", average particle diameter 0.5 [mu] m)} 300 parts were mixed, and uniformly dispersed in a high-speed rotary mixer to prepare a resin varnish. The composition of the obtained resin varnish (excluding the solvent) is shown in Table 1 below.

<Evaluation of hydrophilicity>
On the support (polyethylene terephthalate film), each resin varnish obtained in Examples 1 and 2 and Comparative Examples 1 and 2 was coated with Daiko so that the thickness of the thermosetting resin composition layer after drying was 80 μm. The adhesive film which apply | coated with a ter and dried for 10 minutes at 80-120 degreeC (average 100 degreeC) formed the thermosetting resin composition layer on the support body was manufactured. Using a batch type vacuum pressure laminator (“CVP-600” manufactured by Nichigo Morton Co., Ltd.), this adhesive film is bonded to a 6-inch silicon wafer (625 μm), and the support is peeled off. The cured product layer was formed by heating the resin composition layer at 160 ° C. for 60 minutes. The contact angle of water of the obtained cured product layer was measured with a contact angle meter (“DM-500” manufactured by Kyowa Interface Science Co., Ltd.).
Those having a water contact angle of less than 60 degrees were evaluated as “good”, those having 60 to 80 degrees as “slightly poor”, and those exceeding 80 degrees as “defective”. The results are shown in Table 1 below.

<Evaluation of elastic modulus>
On the support (polyethylene terephthalate film), each resin varnish obtained in Examples 1 and 2 and Comparative Examples 1 and 2 was coated with Daiko so that the thickness of the thermosetting resin composition layer after drying was 80 μm. Was applied at a temperature of 80 to 120 ° C. (average 100 ° C.) for 10 minutes to form a thermosetting resin composition layer on the support to produce an adhesive film. The cured product layer was formed from the thermosetting resin composition layer by thermosetting the film at 180 ° C. for 2 hours. The support was peeled from the cured product layer, and a tensile test based on JIS K7127 was performed using a Tensilon universal testing machine (manufactured by A & D Co., Ltd.) to measure the elastic modulus of the cured product layer.
Those having an elastic modulus of 10 GPa or less were evaluated as “good”, and those having an elastic modulus exceeding 10 Gpa were evaluated as “bad”. The results are shown in Table 1 below.

  As shown from the contact angle of water shown in Table 1, the cured product layer obtained from the resin varnishes of Examples 1 and 2 using the polyimide resin (A1) or (A2) satisfying the requirements of the present invention is Compared to the cured product layers obtained from the resin varnishes of Comparative Examples 1 and 2 that do not use a polyimide resin, the hydrophilicity is excellent. In addition, the cured product obtained from the resin varnish of Comparative Example 2 using a phenoxy resin and a naphthol-based curing agent without using the polyimide resin has an elastic modulus even though the content of the inorganic filler is small. it was high.

  The thermosetting resin composition of the present invention is useful for forming an insulating layer of a circuit board such as a flexible circuit board or a wafer level chip size package.

  This application is based on Japanese Patent Application No. 2015-023364 filed in Japan, the contents of which are incorporated in full herein.

Claims (20)

(A) Structure represented by formula (1-a) and structure represented by formula (1-b):

[Wherein R1 represents a residue obtained by removing a hydroxy group of a polycarbonate diol, R2 represents a residue obtained by removing a carboxy group or an acid anhydride group of a polybasic acid or its anhydride, and R3 represents an isocyanate of a diisocyanate compound. The residue without a group is shown. ]
And (B) one or more selected from epoxy resin, bismaleimide resin, cyanate ester resin, bisallyl nadiimide resin, vinyl benzyl ether resin, benzoxazine resin, and a polymer of bismaleimide and diamine A thermosetting resin composition containing a thermosetting resin. The polyimide resin as the component (A) is represented by the formula (abc):

[Wherein, R1 to R3 are as defined in claim 1, and n and m represent integers. ]
The thermosetting resin composition of Claim 1 which has a structure represented by these.   The thermosetting resin composition according to claim 1 or 2, wherein the polycarbonate diol has a number average molecular weight of 500 to 5,000. R1 is represented by the formula (1-c):

[Wherein, k + 1 R4 each independently represents an optionally substituted alkylene group having 1 to 20 carbon atoms, and k represents an integer of 5 to 30. ]
The thermosetting resin composition according to claim 1, wherein the thermosetting resin composition is a divalent group represented by: R2 is represented by the following formula:

[Wherein, A is an oxygen atom, a sulfur atom, CO, SO, SO ₂ , CH ₂ , CH (CH ₃ ), C (CH ₃ ) ₂ , C (CF ₃ ) ₂ , or C (CCl ₃ ) ₂ Indicates. In the formula, a hydrogen atom bonded to a carbon atom may be substituted with a substituent selected from a halogen atom and an alkyl group having 1 to 8 carbon atoms. ]
The thermosetting resin composition according to claim 1, wherein the thermosetting resin composition is one or more selected from the group of tetravalent groups represented by any one of: R3 is represented by the following formula:

[Wherein, the hydrogen atom bonded to the carbon atom may be substituted with a substituent selected from a halogen atom and an alkyl group having 1 to 8 carbon atoms. ]
The thermosetting resin composition according to claim 1, wherein the thermosetting resin composition is at least one selected from the group of divalent groups represented by any one of:   The number average molecular weight of the polyimide resin which is a component (A) is 5,000-25,000, The thermosetting resin composition as described in any one of Claims 1-6.   The number average molecular weight of the polyimide resin which is a component (A) is 5,000-20,000, The thermosetting resin composition as described in any one of Claims 1-6.   The glass transition temperature of the polyimide resin which is a component (A) is 30 degrees C or less, The thermosetting resin composition as described in any one of Claims 1-8.   The thermosetting resin which is a component (B) is an epoxy resin, The thermosetting resin composition as described in any one of Claims 1-9.   The thermosetting resin composition according to claim 10, wherein an epoxy equivalent of the epoxy resin is 90 to 500.   The thermosetting resin composition according to claim 10 or 11, wherein the epoxy resin is a liquid epoxy resin.   The content of the thermosetting resin as the component (B) is 15 to 80 parts by weight with respect to 100 parts by weight of the polyimide resin as the component (A). Thermosetting resin composition.   Furthermore, the thermosetting resin composition as described in any one of Claims 1-13 containing an inorganic filler.   The thermosetting resin composition according to claim 14, wherein the inorganic filler is silica.   The thermosetting resin composition according to claim 14 or 15, wherein the content of the inorganic filler is 50 to 95% by weight in the nonvolatile content of the thermosetting resin composition.   Furthermore, the thermosetting resin composition as described in any one of Claims 1-16 containing a hardening accelerator.   The adhesive film which has the layer formed from the thermosetting resin composition as described in any one of Claims 1-17 on a support body.   The printed wiring board which has the hardened | cured material formed from the thermosetting resin composition as described in any one of Claims 1-17 as an insulating layer.   The wafer level chip size package which has the hardened | cured material formed from the thermosetting resin composition as described in any one of Claims 1-17 as an insulating layer.