Polyimide resins, resin compositions, cured products, adhesive sheets, resin-coated copper foils, copper-clad laminates, printed wiring boards, and polyimide films

Abstract

To provide: a polyimide resin that forms a cured material exhibiting high elongation and elastic modulus; and a resin composition containing the polyimide resin.SOLUTION: The invention relates to: a polyimide resin which is a reaction product of a group of monomers including a tetracarboxylic anhydride (a1) represented by general formula (1) and a diamine (a2) including a dimer diamine; and a resin composition, a cured product, an adhesive sheet, resin-attached copper foil, a copper-clad laminate, a printed wiring board and a polyimide film that comprise the polyimide resin. (R in Formula (1) represents a saturated polycyclic heterocyclic ring structure having an oxygen atom in the ring.)SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a polyimide resin, a resin composition, a cured product, an adhesive sheet, a resin-coated copper foil, a copper-clad laminate, a printed wiring board, and a polyimide film. [Background technology]

[0002] Polyimide resins are generally obtained by reacting tetracarboxylic anhydrides with diamines, and have various properties such as heat resistance, adhesion, and mechanical properties. Therefore, they are used in a variety of applications, such as protective films and insulating sealing films for semiconductors, and adhesives for flexible printed wiring boards and printed circuit boards.

[0003] In recent years, high-frequency electrical signals have been used to transmit and process large amounts of information at high speeds. However, because high-frequency signals are easily attenuated, there is a need for methods to minimize transmission loss in the multilayer wiring boards mentioned above. In this regard, polyimide resins, which have low dielectric properties (low dielectric constant, low dielectric dissipation factor), are useful.

[0004] Known examples of such polyimide resins include resins containing tetracarboxylic acid residues and diamine residues derived from dimer acid, which are used to form adhesive layers in metal-clad laminates having an insulating resin layer, an adhesive layer, and a metal layer (Patent Document 1). Because of the aromatic rings, these polyimide resins exhibit excellent solder heat resistance.

[0005] Furthermore, multilayer circuit boards such as flexible printed wiring boards and printed circuit boards are composed of an insulating sheet layer, a polyimide resin layer, and a conductor processed from copper foil, etc., and are used in bending sections. Therefore, such boards require flexibility, and if this flexibility is insufficient, the conductor may crack, leading to disconnection. Increasing the elongation and elastic modulus is considered to improve flexibility, but the polyimide resin in Patent Document 1 has poor elongation and elastic modulus. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Publication No. 2018-140544 Summary of the Invention [Problem to be solved by the invention]

[0007] The present invention provides a polyimide resin that gives a cured product exhibiting high elongation and elastic modulus, and a resin composition containing the polyimide resin. [Means for solving the problem]

[0008] The present inventors have conducted extensive research focusing on the structure of tetracarboxylic acid anhydrides, and have found that the above-mentioned problems can be solved, thereby completing the present invention. That is, the present invention provides the following.

[0009] 1. A polyimide resin which is a reaction product of a monomer group containing a tetracarboxylic acid anhydride (a1) represented by the general formula (1) and a diamine (a2) including a dimer diamine. [ka] (R in formula (1) represents a saturated polycyclic heterocyclic structure having an oxygen atom in the ring.)

[0010] 2. The polyimide resin according to item 1 above, wherein the component (a1) comprises a compound represented by formula (2): [ka]

[0011] 3. The polyimide resin according to item 1 or 2 above, wherein the component (a2) further contains an alicyclic diamine and / or an aromatic diamine.

[0012] 4. A resin composition comprising the polyimide resin according to any one of items 1 to 3 above and a crosslinking agent.

[0013] 5. A cured product of the resin composition described in the preceding paragraph 4.

[0014] 6. An adhesive sheet having the cured product according to item 5 on at least one surface of a support film.

[0015] 7. A resin-coated copper foil comprising the cured product described in the preceding paragraph 5 and a copper foil.

[0016] 8. A copper-clad laminate comprising the resin-coated copper foil according to the preceding paragraph 7 and a copper foil or an insulating sheet.

[0017] 9. A printed wiring board having a circuit pattern on the copper foil surface of the copper-clad laminate described in the preceding paragraph 8.

[0018] 10. A polyimide film which is a cured product of the polyimide resin according to any one of items 1 to 3 above. [Effects of the Invention]

[0019] The polyimide resin of the present invention and a resin composition containing the resin exhibit high elongation and elastic modulus when cured. This allows the cured product to be flexible and prevents breakage due to cracking of the conductor in resin-coated copper foils, copper-clad laminates, and printed wiring boards. Furthermore, during production of the polyimide resin, the resulting polyimide resin is highly soluble in organic solvents. DETAILED DESCRIPTION OF THE INVENTION

[0020] The polyimide resin of the present invention is a reaction product of a monomer group including a tetracarboxylic anhydride (a1) (hereinafter referred to as component (a1)) represented by general formula (1) and a diamine (a2) (hereinafter referred to as component (a2)) containing a dimer diamine. Hereinafter, this polyimide resin (A) will be referred to as component (A).

[0021] [ka] (R in formula (1) represents a saturated polycyclic heterocyclic structure having an oxygen atom in the ring.)

[0022] The component (a1) is a tetracarboxylic acid anhydride represented by the above-mentioned general formula (1).

[0023] The presence of an ester group in the general formula (1) imparts appropriate hardness to the resulting component (A), resulting in a cured product that exhibits high elongation and elastic modulus. Furthermore, the presence of a saturated polycyclic heterocyclic structure in which R has an oxygen atom in the ring makes the resulting component (A) more soluble in organic solvents.

[0024] A specific example of such component (a1) is preferably one represented by formula (2), as it exhibits the above-mentioned effects more effectively.

[0025] [ka]

[0026] In formula (2), the position where the ester group is bonded to the aromatic ring and the three-dimensional structure of the acid anhydride are not particularly limited. Commercially available products of formula (2) include "ISS-TME" (manufactured by Honshu Chemical Co., Ltd.).

[0027] The amount of the component (a1) used in 100 mol % of the monomers constituting the component (A) is not particularly limited, but is usually 10 to 90 mol %, and preferably 40 to 75 mol %.

[0028] The monomer group may also contain a tetracarboxylic acid anhydride (a1-1) other than the component (a1) (hereinafter referred to as the component (a1-1)). Examples of the component (a1-1) include 2,2',3,3'-biphenyltetracarboxylic acid dianhydride, 2,3',3,4'-biphenyltetracarboxylic acid dianhydride, 3,3',4,4'-biphenyltetracarboxylic acid dianhydride, pyromellitic acid dianhydride, 1,2,3,4-benzenetetracarboxylic acid anhydride, 3,3',4,4'-diphenylsulfonetetracarboxylic acid dianhydride, 4,4'-oxydiphthalic acid anhydride, and 4,4'-[propane-2,2-diylbis(1,4-phenyleneoxy)]diphthalic acid dianhydride. , 2,2',3,3'-benzophenonetetracarboxylic dianhydride, 2,3,3',4'-benzophenonetetracarboxylic dianhydride, 3,3',4,4'-benzophenonetetracarboxylic dianhydride, 2,3',3,4'-diphenyl ether tetracarboxylic dianhydride, bis(2,3-dicarboxyphenyl) ether dianhydride, bis(2,3-dicarboxyphenyl)methane dianhydride, bis(3,4-dicarboxyphenyl)methane dianhydride, 1,1-bis(2,3-dicarboxyphenyl)ethane dianhydride Water, 1,1-bis(3,4-dicarboxyphenyl)ethane dianhydride, 2,2-bis(2,3-dicarboxyphenyl)propane dianhydride, 2,2-bis(3,4-dicarboxyphenyl)propane dianhydride, bis(2,3-dicarboxyphenoxyphenyl)sulfone dianhydride, bis(3,4-dicarboxyphenoxyphenyl)sulfone dianhydride, 1,4,5,8-naphthalenetetracarboxylic anhydride, 2,3,6,7-naphthalenetetracarboxylic anhydride, 2,3,6,7-anthracenetetracarboxylic anhydride carboxylic acid dianhydride, 1,2,5,6-naphthalenetetracarboxylic acid dianhydride, 1,4,5,8-naphthalenetetracarboxylic acid dianhydride, 2,3,6,7-naphthalenetetracarboxylic acid dianhydride, 4,8-dimethyl-1,2,3,5,6,7-hexahydronaphthalene-1,2,5,6-tetracarboxylic acid dianhydride, 2,2-bis(3,4-dicarboxyphenyl)hexafluoropropane dianhydride, 2,2-bis(3,3',4,4'-tetracarboxyphenyl)tetrafluoropropane dianhydride, and the like.These may be used alone or in combination of two or more.

[0029] The amount of component (a1-1) used in 100 mol % of the monomers constituting component (A) is not particularly limited, but is usually 40 mol % or less, preferably 20 mol % or less, and more preferably 10 mol % or less.

[0030] The amount of the (a1-1) component used in 100 mol % of the (a1) component is not particularly limited, but is usually 80 mol % or less, preferably 40 mol % or less, and more preferably 20 mol % or less.

[0031] The component (a2) is a diamine containing dimer diamine.

[0032] Dimer diamine is a dimer acid in which all carboxyl groups have been substituted with primary amino groups or primary aminomethyl groups (see, for example, JP-A-9-12712). Here, dimer acid mainly contains a dibasic acid having 36 carbon atoms obtained by dimerizing unsaturated fatty acids such as oleic acid, linoleic acid, and linolenic acid, and, depending on the degree of purification, includes a monomer acid having 18 carbon atoms, a trimer acid having 54 carbon atoms, and a polymerized fatty acid having 20 to 90 carbon atoms. Note that the dimer acid contains double bonds, and the degree of unsaturation may be reduced by, for example, a hydrogenation reaction.

[0033] The dimer diamine is not particularly limited, and examples thereof include those represented by the following general formula (3): In general formula (3), m+n preferably represents 6 to 17, and p+q preferably represents 8 to 19, and the dashed line represents a carbon-carbon single bond or a carbon-carbon double bond.

[0034] [ka]

[0035] Commercially available dimer diamine products include "VERSAMINE 551" and "VERSAMINE 552" (both manufactured by Cognics Japan Co., Ltd.), "PRIAMINE 1073", "PRIAMINE 1074", and "PRIAMINE 1075" (all manufactured by Croda Japan Co., Ltd.).

[0036] Furthermore, the dimer diamine may be used as it is, or may be used after being subjected to a purification treatment such as distillation.

[0037] The amount of dimer diamine used in 100 mol % of the monomers constituting the component (A) is not particularly limited, but is usually 5 mol % or more, and preferably 25 to 75 mol %.

[0038] The amount of dimer diamine used in 100 mol % of the component (a2) is not particularly limited, but is usually 10 mol % or more, preferably 30 to 100 mol %.

[0039] The component (a2) may also contain a diamine (a2-1) other than dimer diamine (hereinafter referred to as component (a2-1)). The component (a2-1) may also contain, for example, an aliphatic diamine, an alicyclic diamine, an aromatic diamine, a diaminoether, or a diaminopolysiloxane. Note that these amines exclude dimer diamine.

[0040] Examples of aliphatic diamines include ethylenediamine, 1,3-diaminopropane, 1,4-diaminobutane, 1,5-diaminopentane, 1,6-diaminohexane, 1,7-diaminoheptane, 1,8-diaminooctane, 1,9-diaminononane, 1,10-diaminodecane, 1,11-diaminoundecane, and 1,12-diaminododecane.

[0041] Examples of alicyclic diamines include diaminocyclohexane, diaminodicyclohexylmethane, dimethyldiaminodicyclohexylmethane, diaminodicyclohexylpropane, tetramethyldiaminodicyclohexylmethane, 1,3-bis(aminomethyl)cyclohexane, 1,4-bis(aminomethyl)cyclohexane, diaminobicyclo[2.2.1]heptane, bis(aminomethyl)-bicyclo[2.2.1]heptane, 3(4),8(9)-bis(aminomethyl)tricyclo[5.2.1.0(2,6)]decane, and isophoronediamine.

[0042] Examples of aromatic diamines include diaminobiphenyls such as 2,2'-diaminobiphenyl, 3,3'-diaminobiphenyl, 4,4'-diaminobiphenyl, 2,2'-dimethyl-4,4'-diaminobiphenyl, 2,2'-diethyl-4,4'-diaminobiphenyl, and 2,2'-di-n-propyl-4,4'-diaminobiphenyl; bisaminophenoxyphenylpropanes such as 2,2-bis[4-(3-aminophenoxy)phenyl]propane and 2,2-bis[4-(4-aminophenoxy)phenyl]propane; diaminodiphenyl ethers such as 3,3'-diaminodiphenyl ether, 3,4'-diaminodiphenyl ether, and 4,4'-diaminodiphenyl ether; Phenylenediamines such as p-phenylenediamine and m-phenylenediamine; Diaminodiphenyl sulfides such as 3,3'-diaminodiphenyl sulfide, 3,4'-diaminodiphenyl sulfide, and 4,4'-diaminodiphenyl sulfide; diaminodiphenyl sulfones such as 3,3'-diaminodiphenyl sulfone, 3,4'-diaminodiphenyl sulfone, and 4,4'-diaminodiphenyl sulfone; Diaminobenzophenones such as 3,3'-diaminobenzophenone, 3,4'-diaminobenzophenone, and 4,4'-diaminobenzophenone; diaminodiphenylmethanes such as 3,3'-diaminodiphenylmethane, 3,4'-diaminodiphenylmethane, 4,4'-diaminodiphenylmethane, and bis[4-(3-aminophenoxy)phenyl]methane; diaminophenylpropanes such as 2,2-di(3-aminophenyl)propane, 2,2-di(4-aminophenyl)propane, and 2-(3-aminophenyl)-2-(4-aminophenyl)propane; diaminophenylhexafluoropropanes such as 2,2-di(3-aminophenyl)-1,1,1,3,3,3-hexafluoropropane, 2,2-di(4-aminophenyl)-1,1,1,3,3,3-hexafluoropropane, and 2-(3-aminophenyl)-2-(4-aminophenyl)-1,1,1,3,3,3-hexafluoropropane; diaminophenylphenylethanes such as 1,1-di(3-aminophenyl)-1-phenylethane, 1,1-di(4-aminophenyl)-1-phenylethane, and 1-(3-aminophenyl)-1-(4-aminophenyl)-1-phenylethane; bisaminophenoxybenzenes such as 1,3-bis(3-aminophenoxy)benzene, 1,3-bis(4-aminophenoxy)benzene, 1,4-bis(3-aminophenoxy)benzene, and 1,4-bis(4-aminophenoxy)benzene; bisaminobenzoylbenzenes such as 1,3-bis(3-aminobenzoyl)benzene, 1,3-bis(4-aminobenzoyl)benzene, 1,4-bis(3-aminobenzoyl)benzene, and 1,4-bis(4-aminobenzoyl)benzene; bisaminodimethylbenzylbenzenes such as 1,3-bis(3-amino-α,α-dimethylbenzyl)benzene, 1,3-bis(4-amino-α,α-dimethylbenzyl)benzene, 1,4-bis(3-amino-α,α-dimethylbenzyl)benzene, and 1,4-bis(4-amino-α,α-dimethylbenzyl)benzene; bisaminoditrifluoromethylbenzylbenzenes such as 1,3-bis(3-amino-α,α-ditrifluoromethylbenzyl)benzene, 1,3-bis(4-amino-α,α-ditrifluoromethylbenzyl)benzene, 1,4-bis(3-amino-α,α-ditrifluoromethylbenzyl)benzene, and 1,4-bis(4-amino-α,α-ditrifluoromethylbenzyl)benzene; aminophenoxybiphenyls such as 4,4'-bis(3-aminophenoxy)biphenyl, 4,4'-bis(4-aminophenoxy)biphenyl, and bis[1-(3-aminophenoxy)]biphenyl; Aminophenoxyphenyl ketones such as bis[4-(3-aminophenoxy)phenyl]ketone and bis[4-(4-aminophenoxy)phenyl]ketone; Aminophenoxyphenyl sulfides such as bis[4-(3-aminophenoxy)phenyl]sulfide and bis[4-(4-aminophenoxy)phenyl]sulfide; aminophenoxyphenyl sulfones such as bis[4-(3-aminophenoxy)phenyl]sulfone and bis[4-(4-aminophenoxy)phenyl]sulfone; aminophenoxyphenyl ethers such as bis[4-(3-aminophenoxy)phenyl]ether and bis[4-(4-aminophenoxy)phenyl]ether; aminophenoxyphenylpropanes such as 2,2-bis[4-(3-aminophenoxy)phenyl]propane, 2,2-bis[3-(3-aminophenoxy)phenyl]-1,1,1,3,3,3-hexafluoropropane, and 2,2-bis[4-(4-aminophenoxy)phenyl]-1,1,1,3,3,3-hexafluoropropane; Bis(aminophenoxybenzoyl)benzenes such as 1,3-bis[4-(3-aminophenoxy)benzoyl]benzene, 1,3-bis[4-(4-aminophenoxy)benzoyl]benzene, 1,4-bis[4-(3-aminophenoxy)benzoyl]benzene, and 1,4-bis[4-(4-aminophenoxy)benzoyl]benzene; bis(aminophenoxy-α,α-dimethylbenzyl)benzenes such as 1,3-bis[4-(3-aminophenoxy)-α,α-dimethylbenzyl]benzene, 1,3-bis[4-(4-aminophenoxy)-α,α-dimethylbenzyl]benzene, 1,4-bis[4-(3-aminophenoxy)-α,α-dimethylbenzyl]benzene, and 1,4-bis[4-(4-aminophenoxy)-α,α-dimethylbenzyl]benzene; bis[(aminoaryloxy)benzoyl]diphenyl ethers such as 4,4'-bis[4-(4-aminophenoxy)benzoyl]diphenyl ether; Bis(amino-α,α-dimethylbenzylphenoxy)benzophenones such as 4,4'-bis[4-(4-amino-α,α-dimethylbenzyl)phenoxy]benzophenone: bis[amino-α,α-dimethylbenzylphenoxy]diphenyl sulfone such as 4,4'-bis[4-(4-amino-α,α-dimethylbenzyl)phenoxy]diphenyl sulfone; bis[aminophenoxyphenoxy]diphenyl sulfones such as 4,4'-bis[4-(4-aminophenoxy)phenoxy]diphenyl sulfone; diaminodiaryloxybenzophenones such as 3,3'-diamino-4,4'-diphenoxybenzophenone and 3,3'-diamino-4,4'-dibiphenoxybenzophenone; diaminoaryloxybenzophenones such as 3,3'-diamino-4-phenoxybenzophenone and 3,3'-diamino-4-biphenoxybenzophenone; Examples thereof include 1-(4-aminophenyl)-2,3-dihydro-1,3,3-trimethyl-1H-inden-5-amine and 9,9-bis(4-aminophenyl)fluorene.

[0043] Examples of diamino ethers include bis(aminomethyl) ether, bis(2-aminoethyl) ether, bis(3-aminopropyl) ether, bis[(2-aminomethoxy)ethyl]ether, bis[2-(2-aminoethoxy)ethyl]ether, bis[2-(3-aminoprotoxy)ethyl]ether, 1,2-bis(aminomethoxy)ethane, 1,2-bis(2-aminoethoxy)ethane, 1,2-bis[2-(aminomethoxy)ethoxy]ethane, 1,2-bis[2-(2-aminoethoxy)ethoxy]ethane, ethylene glycol bis(3-aminopropyl)ether, diethylene glycol bis(3-aminopropyl)ether, and triethylene glycol bis(3-aminopropyl)ether.

[0044] Examples of diaminopolysiloxanes include α,ω-bis(2-aminoethyl)polydimethylsiloxane, α,ω-bis(3-aminopropyl)polydimethylsiloxane, α,ω-bis(4-aminobutyl)polydimethylsiloxane, α,ω-bis(5-aminopentyl)polydimethylsiloxane, α,ω-bis[3-(2-aminophenyl)propyl]polydimethylsiloxane, and α,ω-bis[3-(4-aminophenyl)propyl]polydimethylsiloxane.

[0045] These components (a2-1) may be used alone or in combination of two or more. Among them, alicyclic diamines and aromatic diamines are preferred, and aromatic diamines are more preferred, in that the polyimide resin layer exhibits excellent solder heat resistance.

[0046] There are no particular restrictions on the amount of component (a2-1) used in 100 mol % of the monomers constituting component (A), but it is usually 90 mol % or less, and preferably 50 mol % or less.

[0047] The amount of the component (a2-1) used in 100 mol % of the component (a2) is not particularly limited, but is usually 90 mol % or less, and preferably 70 mol % or less.

[0048] Component (A) of the present invention can be obtained by various known production methods. Examples of such production methods include a step of polyaddition-reacting a group of monomers including components (a1) and (a2) at a temperature of preferably about 30 to 120°C, more preferably about 60 to 100°C, for a time of preferably about 0.1 to 2 hours, more preferably about 0.1 to 0.5 hours, to obtain a polyadduct, and a step of imidizing the resulting polyadduct, i.e., subjecting it to a dehydration ring-closing reaction, at a temperature of preferably about 80 to 250°C, more preferably about 100 to 170°C, for a time of preferably about 0.5 to 50 hours, more preferably about 1 to 20 hours. The method and order of mixing components (a1) and (a2) are not particularly limited.

[0049] In the imidization reaction step, various known reaction catalysts, dehydrating agents, and organic solvents may be used, and these may be used alone or in combination of two or more.

[0050] Examples of the reaction catalyst include aliphatic tertiary amines such as triethylamine, aromatic tertiary amines such as dimethylaniline, and heterocyclic tertiary amines such as pyridine, picoline, and isoquinoline. Examples of the dehydrating agent include aliphatic carboxylic acid anhydrides such as acetic anhydride, and aromatic carboxylic acid anhydrides such as benzoic anhydride.

[0051] Examples of the organic solvent include nitrogen-based organic solvents such as N-methyl-2-pyrrolidone, N,N-dimethylformamide, N,N-diethylformamide, N,N-dimethylacetamide, N,N-diethylacetamide, and diazabicycloundecene; aliphatic ketones such as methyl ethyl ketone, methyl-n-propyl ketone, methyl isopropyl ketone, n-butyl methyl ketone, isobutyl methyl ketone, diethyl ketone, ethyl-n-propyl ketone, ethyl isopropyl ketone, n-butyl ethyl ketone, and di-n-propyl ketone; Alicyclic ketones such as cyclopropyl methyl ketone, cyclobutanone, cyclobutyl methyl ketone, cyclopentanone, cyclohexanone, and methylcyclohexanone; aliphatic esters such as n-propyl formate, isopropyl formate, n-butyl formate, isobutyl formate, n-pentyl formate, isopentyl formate, ethyl acetate, n-propyl acetate, isopropyl acetate, n-butyl acetate, isobutyl acetate, n-pentyl acetate, isopentyl acetate, methyl propionate, ethyl propionate, n-propyl propionate, isopropyl propionate, and n-butyl propionate; alkyl carbonate esters such as dimethyl carbonate, ethyl methyl carbonate, and diethyl carbonate; Alicyclic esters such as methyl cyclopropanecarboxylate, ethyl cyclopropanecarboxylate, and methyl cyclobutanecarboxylate; aliphatic ethers such as ethyl-n-propyl ether, di-n-propyl ether, diisopropyl ether, 1,2-dimethoxyethane, 1,1-diethoxyethane, 1,2-diethoxyethane, 1,2-dimethoxypropane, 2,2-dimethoxypropane, 1,1-diethoxypropane, and 2,2-diethoxypropane; cyclic ethers such as tetrahydrofuran and dioxane; Alcohols such as methanol, ethanol, n-propyl alcohol, isopropyl alcohol, 1-methoxy-2-propyl alcohol, and t-butyl alcohol; aliphatic hydrocarbons such as 2-methylpentane, 3-ethylpentane, n-hexane, 2-methylhexane, 3-methylhexane, 3-ethylhexane, n-heptane, 2-methylheptane, 3-methylheptane, 4-methylheptane, 3-ethylheptane, n-octane, 2-methyloctane, 3-methyloctane, and 4-methyloctane; Alicyclic hydrocarbons such as methylcyclopentane, ethylcyclopentane, n-propylcyclopentane, isopropylcyclopentane, n-butylcyclopentane, isobutylcyclopentane, cyclohexane, methylcyclohexane, ethylcyclohexane, 1,1-dimethylcyclohexane, 1-ethyl-3-methylcyclohexane, and cycloheptane; Examples include aromatic hydrocarbons such as benzene, toluene, and xylene; dimethyl sulfoxide, etc. These may be used alone or in combination of two or more.

[0052] The amount of the organic solvent used is adjusted so that the reaction concentration is 5 to 60% by mass, preferably 20 to 50% by mass.

[0053] The imide ring closure rate of the component (A) is preferably 90 to 100%, and more preferably about 95 to 100%, in order to obtain a component (A) that has both a high softening point and high flexibility. It is presumed that when the imide ring closure rate of component (A) is within the above range, component (A) is likely to form a hard segment and soft segment structure, resulting in a high softening point and high flexibility. Here, the "imide ring closure rate" refers to the content of cyclic imide bonds in the polyimide resin of component (A), and can be determined by various spectroscopic means, such as NMR or IR analysis.

[0054] Regarding the physical properties of component (A), for example, the weight average molecular weight is preferably 10,000 to 100,000. Furthermore, the number average molecular weight of component (A) is preferably 5,000 to 50,000. The weight average molecular weight and number average molecular weight are determined, for example, as polystyrene-equivalent values ​​measured by gel permeation chromatography (GPC).

[0055] The softening point of component (A) of the present invention is preferably about 50 to 250° C., more preferably about 80 to 200° C., in order to facilitate processing by press hardening during the production of laminates such as copper-clad laminates. The softening point refers to the temperature at which the storage modulus begins to decrease in the profile of the storage modulus measured using a commercially available measuring device (product name "ARES-2KSTD-FCO-STD", manufactured by Rheometric Scientific Co., Ltd.).

[0056] [Resin composition] The resin composition of the present invention contains the polyimide resin of the present invention and a crosslinking agent.

[0057] The content of the polyimide resin in the resin composition of the present invention is preferably about 5 to 95 mass %, and more preferably about 50 to 90 mass %, based on 100 mass % of the nonvolatile content of the resin composition.

[0058] The crosslinking agent is not particularly limited as long as it functions as a crosslinking agent for polyimide resins. Examples of crosslinking agents include epoxy resins, benzoxazines, bismaleimides, cyanate esters, polyisocyanates, and trimer triamines. These may be used alone or in combination of two or more.

[0059] Examples of epoxy resins include phenol novolac type epoxy resins, cresol novolac type epoxy resins, bisphenol A type epoxy resins, bisphenol F type epoxy resins, bisphenol S type epoxy resins, hydrogenated bisphenol A type epoxy resins, hydrogenated bisphenol F type epoxy resins, stilbene type epoxy resins, triazine skeleton-containing epoxy resins, fluorene skeleton-containing epoxy resins, linear aliphatic epoxy resins, alicyclic epoxy resins, glycidylamine type epoxy resins, triphenolmethane type epoxy resins, alkyl-modified triphenolmethane type epoxy resins, biphenyl type epoxy resins, dicyclopentadiene skeleton-containing epoxy resins, naphthalene skeleton-containing epoxy resins, aryl alkylene type epoxy resins, tetraglycidylxylylenediamine, dimer acid-modified epoxides which are dimer acid-modified products of the above epoxides, and dimer acid diglycidyl esters. Commercially available epoxy resins include "jER828," "jER834," "jER807," "jER604," "jER630," "jER871," and "jER872" (all manufactured by Mitsubishi Chemical Corporation), "ST-3000," "YD-172-X75" (manufactured by Nippon Steel Chemical & Material Co., Ltd.), "Celloxide 2021P" (manufactured by Daicel Corporation), "TETRAD-X" (manufactured by Mitsubishi Gas Chemical Company, Inc.), "Sanso Cizer E-2000H" (manufactured by New Japan Chemical Co., Ltd.), "NC-513," "NC-514S," and "NC-547" (manufactured by Cardolite Corp.). Among these, bisphenol A epoxide, bisphenol F epoxide, hydrogenated bisphenol A epoxide, and alicyclic epoxide are preferred from the viewpoint of the balance between solder heat resistance and low dielectric properties.

[0060] When an epoxy resin is used as a crosslinking agent, various known curing agents for epoxy resins and active ester curing agents can be used in combination. These curing agents can be used alone or in combination of two or more.

[0061] Examples of epoxy resin curing agents include acid anhydride curing agents such as succinic anhydride, phthalic anhydride, maleic anhydride, trimellitic anhydride, pyromellitic anhydride, hexahydrophthalic anhydride, 3-methylhexahydrophthalic anhydride, 4-methyl-hexahydrophthalic anhydride, a mixture of 4-methylhexahydrophthalic anhydride and hexahydrophthalic anhydride, tetrahydrophthalic anhydride, methyl-tetrahydrophthalic anhydride, nadic anhydride, methylnadic anhydride, norbornane-2,3-dicarboxylic anhydride, methylnorbornane-2,3-dicarboxylic anhydride, methylcyclohexene dicarboxylic anhydride, 3-dodecenylsuccinic anhydride, and octenylsuccinic anhydride; Amine-based curing agents such as dicyandiamide (DICY), aromatic diamines (such as "Lonzacure M-DEA" and "Lonzacure M-DETDA" (both manufactured by Lonza Japan Co., Ltd.)), and aliphatic amines (such as "Vegichem Green V140," "Vegichem Green V150," and "Vegichem Green G747" (both manufactured by Tsuno Foods Industries Co., Ltd.)); phenolic curing agents such as phenol novolac resin, cresol novolac resin, bisphenol A novolac resin, triazine-modified phenol novolac resin, and phenolic hydroxyl group-containing phosphazenes ("SPH-100" (manufactured by Otsuka Chemical Co., Ltd.), "NX-9001LP", "NX-9006", and "NX-9201LP" (all manufactured by Cardolite Corp.), etc.); Rosin-based hardeners such as maleic acid-modified rosin and its hydrogenated derivatives; Examples include cyclic phosphazene compounds.

[0062] Examples of active ester-based curing agents include those containing a dicyclopentadienyldiphenol structure described in JP-A-2019-183071, those containing a naphthalene structure, acetylated phenol novolac, and benzoylated phenol novolac. Commercially available active ester curing agents include, for example: Those containing a dicyclopentadienyldiphenol structure, such as "EXB9451", "EXB9460", "EXB9460S", "HPC-8000", "HPC-8000H", "HPC-8000-65T", "HPC-8150-62T", "HPC-8000H-65MT", "HPC-8000L-65MT", "EXB-8000L", "EXB-8000L-65MT", and "EXB-8150-65T" (all manufactured by DIC Corporation); Those containing a naphthalene structure include "EXB9416-70BK" (DIC Corporation); Acetylated phenol novolac, "DC808" (Mitsubishi Chemical Corporation); Benzoylated phenol novolak compounds such as "YLH1026," "YLH1030," and "YLH1048" (manufactured by Mitsubishi Chemical Corporation) are examples.

[0063] The active ester curing agent may be one produced by various known methods, such as a reaction product of a polyfunctional phenol compound with an aromatic carboxylic acid, as described in Japanese Patent No. 5152445.

[0064] Among the curing agents, active ester curing agents and phenolic curing agents are preferred, with active ester curing agents being particularly preferred. The amount of curing agent used is preferably about 0.1 to 40% by mass, and more preferably about 1 to 20% by mass, based on 100% by mass of the nonvolatile content of the resin composition.

[0065] When using an epoxy resin and an epoxy resin curing agent as a crosslinking agent, a reaction catalyst can also be used. Examples of reaction catalysts include tertiary amines such as 1,8-diaza-bicyclo[5.4.0]undecene-7, triethylenediamine, benzyldimethylamine, triethanolamine, dimethylaminoethanol, and tris(dimethylaminomethyl)phenol; imidazoles such as 2-methylimidazole, 2-phenylimidazole, 2-phenyl-4-methylimidazole, and 2-heptadecylimidazole; organic phosphines such as tributylphosphine, methyldiphenylphosphine, triphenylphosphine, diphenylphosphine, and phenylphosphine; and tetraphenylboron salts such as tetraphenylphosphonium tetraphenylborate, 2-ethyl-4-methylimidazole tetraphenylborate, and N-methylmorpholine tetraphenylborate. These may be used alone or in combination. The amount of the reaction catalyst used is preferably about 0.01 to 5% by mass, with the nonvolatile content of the resin composition being 100% by mass.

[0066] Examples of benzoxazines include 6,6-(1-methylethylidene)bis(3,4-dihydro-3-phenyl-2H-1,3-benzoxazine) and 6,6-(1-methylethylidene)bis(3,4-dihydro-3-methyl-2H-1,3-benzoxazine). A phenyl group, a methyl group, a cyclohexyl group, or the like may be bonded to the nitrogen of the oxazine ring. Commercially available benzoxazines include "Benzoxazine Fa type" and "Benzoxazine Pd type" (both manufactured by Shikoku Chemicals Corporation), and "RLV-100" (manufactured by Air Water Inc.).

[0067] Examples of bismaleimides include 4,4'-diphenylmethane bismaleimide, m-phenylene bismaleimide, bisphenol A diphenyl ether bismaleimide, 3,3'-dimethyl-5,5'-diethyl-4,4'-diphenylmethane bismaleimide, 4-methyl-1,3-phenylene bismaleimide, 1,6'-bismaleimide-(2,2,4-trimethyl)hexane, 4,4'-diphenyl ether bismaleimide, 4,4'-diphenylsulfone bismaleimide, etc. Commercially available bismaleimides include "BAF-BMI" (manufactured by JFE Chemical Corporation), "BMI-1000H" (manufactured by Daiwa Chemical Industry Co., Ltd.), and "BMI-689" (manufactured by DESIGNER MOLECULES Inc.).

[0068] Examples of cyanate esters include 2-allylphenol cyanate ester, 4-methoxyphenol cyanate ester, 2,2-bis(4-isocyanatophenyl)-1,1,1,3,3,3-hexafluoropropane, bisphenol A cyanate ester, diallylbisphenol A cyanate ester, 4-phenylphenol cyanate ester, 1,1,1-tris(4-cyanatophenyl)ethane, 4-cumylphenol cyanate ester, 1,1-bis(4-cyanatophenyl)ethane, 4,4'-bisphenol cyanate ester, and 2,2-bis(4-cyanatophenyl)propane. Commercially available cyanate esters include "PRIMASET BTP-6020S" (manufactured by Lonza Japan Co., Ltd.).

[0069] Examples of polyisocyanates include linear aliphatic diisocyanates such as methylene diisocyanate, dimethylene diisocyanate, trimethylene diisocyanate, tetramethylene diisocyanate, pentamethylene diisocyanate, hexamethylene diisocyanate, heptamethylene diisocyanate, octamethylene diisocyanate, nonamethylene diisocyanate, and decamethylene isocyanate; Branched aliphatic polyisocyanates such as trimethylbutylene diisocyanate, trimethylpentylene diisocyanate, and trimethylhexamethylene diisocyanate; Alicyclic polyisocyanates such as dicyclohexylmethane-4,4'-diisocyanate, isophorone diisocyanate, cyclopentylene diisocyanate, 1,4-cyclohexylene diisocyanate, cycloheptylene diisocyanate, norbornene diisocyanate, norbornenemethane diisocyanate, adamantane diisocyanate, cyclohexane-1,4-diylbis(methylene)diisocyanate, 3,5,5-trimethylcyclohexylene diisocyanate, tricyclodecylene diisocyanate, hydrogenated xylylene diisocyanate, hydrogenated tolylene diisocyanate, hydrogenated tetramethylxylylene diisocyanate, hydrogenated diphenylmethane diisocyanate, hydrogenated dimethyldiphenylmethane diisocyanate, and hydrogenated naphthalene diisocyanate; Examples of the aromatic polyisocyanate include xylylene diisocyanate, tolylene diisocyanate, phenylene diisocyanate, tetramethyl xylylene diisocyanate, diphenylmethane diisocyanate, dimethyldiphenylmethane diisocyanate, m-tetramethyl xylylene diisocyanate, and naphthalene diisocyanate.

[0070] As the polyisocyanate, biuret, isocyanurate, allophanate, and adduct of the above polyisocyanates can also be used. These polyisocyanates can be used alone or in combination of two or more.

[0071] Commercially available polyisocyanates include, for example: Examples of biuret compounds include "Duranate 24A-100," "Duranate 22A-75P," and "Duranate 21S-75E" (all manufactured by Asahi Kasei Corporation), and "Desmodur N3200A" (all manufactured by Sumitomo Bayer Urethane Co., Ltd.). Examples of isocyanurate compounds include "Duranate TPA-100," "Duranate TKA-100," "Duranate MFA-75B," and "Duranate MHG-80B" (all manufactured by Asahi Kasei Corporation), "Coronate HXR" (manufactured by Tosoh Corporation), "Takenate D-131N," "Takenate D204EA-1," and "Takenate D-127N" (all manufactured by Mitsui Chemicals, Inc.), and "VESTANAT T1890 / 100" (manufactured by Evonik Japan Co., Ltd.). Examples of allophanate compounds include "Takenate D-178N" (manufactured by Mitsui Chemicals, Inc.), Examples of the adduct include "Duranate P301-75E" (manufactured by Asahi Kasei Corporation), "Takenate D110N" and "Takenate D160N" (all manufactured by Mitsui Chemicals, Inc.), and "Coronate L" (manufactured by Tosoh Corporation).

[0072] Trimer triamines are trimer acids, which are trimers of unsaturated fatty acids such as oleic acid, linoleic acid, and linolenic acid (see, for example, JP-A-2013-505345), in which all carboxyl groups have been substituted with primary amino groups, and various known compounds can be used. Non-limiting examples of such compounds include those described in, for example, JP-A-2017-186551.

[0073] An example of a commercially available trimer triamine is "PRIAMINE 1071" (manufactured by Croda Japan Co., Ltd.) The content of trimer triamine in the commercially available product is about 15 to 20% by mass, and the remainder may be more than 80% by mass of dimer diamine.

[0074] The content of the crosslinking agent in the resin composition of the present invention is preferably about 1 to 900 parts by mass per 100 parts by mass (nonvolatile content) of the component (A) in the resin composition.

[0075] The content of the crosslinking agent in the resin composition of the present invention is preferably about 1 to 80% by mass, with the nonvolatile content of the resin composition being 100% by mass.

[0076] The resin composition of the present invention may contain a flame retardant. The flame retardant may be used alone or in combination of two or more. Examples of the flame retardant include phosphorus-based flame retardants and inorganic fillers.

[0077] Examples of phosphorus-based flame retardants include polyphosphoric acid, phosphate esters, and phosphazene derivatives that do not have a phenolic hydroxyl group. Among the phosphazene derivatives, cyclic phosphazene derivatives are preferred in terms of flame retardancy, heat resistance, bleed-out resistance, etc. Commercially available cyclic phosphazene derivatives include "SPB-100" (manufactured by Otsuka Chemical Co., Ltd.) and "Ravitor FP-300B" (manufactured by Fushimi Pharmaceutical Co., Ltd.).

[0078] Examples of inorganic fillers include silica fillers, phosphorus-based fillers, fluorine-based fillers, and inorganic ion exchange fillers. Silica fillers whose surfaces have been modified with a treatment agent such as a silane coupling agent may also be used. Commercially available inorganic fillers include "FB-3SDC" and "SFP-20M" (all manufactured by Denka Co., Ltd.), "SC-2500-SPJ," "SC-2500-SXJ," "SC-2500-SVJ," and "SC-2500-SEJ" (all manufactured by Admatechs Co., Ltd.), "Exolit OP935" (manufactured by Clariant Chemicals Co., Ltd.), "KTL-500F" (manufactured by Kitamura Co., Ltd.), and "IXE" (manufactured by Toagosei Co., Ltd.).

[0079] The content of the flame retardant in the resin composition of the present invention is preferably 1 to 150 parts by mass per 100 parts by mass (nonvolatile content) of the component (A) in the resin composition.

[0080] The content of the flame retardant in the resin composition of the present invention is preferably about 1 to 75 mass % based on 100 mass % of the nonvolatile content of the resin composition.

[0081] The resin composition of the present invention contains a compound having the general formula: W-Si(R 1 ) a (OR 2 ) 3-a (Wherein, W represents a group containing a functional group reactive with an acid anhydride group, R 1represents hydrogen or a hydrocarbon group having 1 to 8 carbon atoms, R 2 represents a hydrocarbon group having 1 to 8 carbon atoms, and a represents 0, 1, or 2. The reactive alkoxysilyl compound may contain a reactive alkoxysilyl compound represented by the following formula: (wherein a represents a hydrocarbon group having 1 to 8 carbon atoms, and a represents 0, 1, or 2). The reactive alkoxysilyl compound can adjust the melt viscosity of the resin composition layer while maintaining the low dielectric properties of the resin composition layer. As a result, the interfacial adhesion between the resin composition layer and the support (the so-called anchor effect) can be increased, while bleeding of the cured layer from the edge of the support can be suppressed.

[0082] Examples of the reactive functional group contained in W in the general formula include an amino group, an epoxy group, and a thiol group.

[0083] Examples of compounds in which W contains an amino group include N-2-(aminoethyl)-3-aminopropylmethyldimethoxysilane, N-2-(aminoethyl)-3-aminopropyltrimethoxysilane, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, and 3-ureidopropyltrialkoxysilane. Examples of compounds in which W contains an epoxy group include 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, and 3-glycidoxypropyltriethoxysilane. Examples of compounds in which W contains a thiol group include 3-mercaptopropyltrimethoxysilane, 3-mercaptopropyltriethoxysilane, 3-mercaptopropylmethyldimethoxysilane, and 3-mercaptopropylmethyldiethoxysilane. Among these, compounds in which W contains an amino group are preferred because of their good reactivity and flow control effects.

[0084] The content of the reactive alkoxysilyl compound in the resin composition of the present invention is preferably 0.01 to 5 parts by mass per 100 parts by mass (non-volatile content) of the component (A) of the present invention in the resin composition.

[0085] The content of the reactive alkoxysilyl compound in the resin composition of the present invention is preferably about 0.01 to 8% by mass, with the nonvolatile content of the resin composition being 100% by mass.

[0086] The resin composition of the present invention may contain an additive other than the polyimide resin of the present invention, a crosslinking agent, a flame retardant, or a reactive alkoxysilyl compound.

[0087] Examples of the additives include a ring-opening esterification reaction catalyst, a dehydrating agent, a plasticizer, a weathering agent, an antioxidant, a heat stabilizer, a lubricant, an antistatic agent, a whitening agent, a colorant, a conductive agent, a release agent, a surface treatment agent, a viscosity modifier, a silica filler, and a fluorine filler.

[0088] The content of the additives may be less than 1 mass %, less than 0.1 mass %, less than 0.01 mass %, or 0 mass % relative to 100 mass % of the nonvolatile content of the resin composition.

[0089] The content of the additive may be less than 1 part by mass, less than 0.1 part by mass, less than 0.01 part by mass, or 0 part by mass per 100 parts by mass (nonvolatile content) of the component (A) in the resin composition.

[0090] The resin composition of the present invention can be obtained by dissolving the crosslinking agent, and optionally the flame retardant, reactive alkoxysilyl compound, and additives in the polyimide resin of the present invention. In preparing the resin composition, the organic solvent may be further added.

[0091] [Cured product] The present invention also relates to a cured product of the resin composition. Examples of methods for producing the cured product include a method including the steps of applying the resin composition to a suitable support, curing the composition by heating to volatilize the organic solvent, and peeling off the support. The thickness of the cured product is preferably 3 to 40 μm. Examples of the support include release paper, release film, and the support film described below. When producing the cured product, the resin composition may be used in combination with various known resin compositions other than the resin composition.

[0092] [Adhesive sheet] The adhesive sheet of the present invention comprises a support film and the cured product of the present invention on at least one surface thereof.

[0093] The adhesive sheet can be obtained, for example, by applying the resin composition of the present invention onto a support film and curing it by heating, or by laminating the cured product of the present invention onto a support film.

[0094] Examples of the support film include polyimide, polyester, polyimide-silica hybrid, polyethylene, polypropylene, polyethylene terephthalate, polyethylene naphthalate, polymethyl methacrylate resin, polystyrene resin, polycarbonate resin, acrylonitrile-butadiene-styrene resin, ethylene terephthalate, aromatic polyester resin obtained from phenol, phthalic acid, hydroxynaphthoic acid, or the like and parahydroxybenzoic acid (so-called liquid crystal polymer; "Vextar" (manufactured by Kuraray Co., Ltd.), etc.), cycloolefin polymer, fluorine-based resin (polytetrafluoroethylene (PTFE), perfluoroalkoxyalkane (PFA), polyvinylidene fluoride (PVDF), etc.), etc. Polyimide includes the polyimide film of the present invention.

[0095] When the resin composition of the present invention is applied to the support film, examples of the application method include a comma, die, knife, lip, or other coater. The thickness of the coating layer after drying is preferably about 1 to 100 μm, more preferably about 3 to 50 μm. The cured layer of the adhesive sheet may be protected with various protective films.

[0096] [Resin-coated copper foil] The resin-coated copper foil of the present invention includes the cured product of the present invention and a copper foil. Specifically, the resin composition of the present invention is applied to a copper foil and then heat-cured, or the cured product of the present invention is laminated to the copper foil. Examples of the copper foil include rolled copper foil and electrolytic copper foil, and those that have been subjected to various surface treatments (roughening, rust prevention, etc.) can also be used. Examples of rust prevention treatments include so-called mirror-finish treatments such as plating using a plating solution containing Ni, Zn, Sn, etc., and chromate treatment.

[0097] The thickness of the copper foil is preferably about 1 to 100 μm, more preferably about 2 to 38 μm. Coating means include the methods described above.

[0098] The resin composition layer or cured product of the resin-coated copper foil may be partially or completely cured under heat. The partially cured resin composition layer or cured product is in a state known as B-stage. The thickness of the resin composition layer or cured product is preferably about 0.5 to 30 μm. Furthermore, a resin can be laminated to the copper foil of the resin-coated copper foil to produce a double-sided resin-coated copper foil.

[0099] [Copper-clad laminate] The copper-clad laminate of the present invention comprises the resin-coated copper foil of the present invention and a copper foil or insulating sheet. The copper-clad laminate is also called CCL (Copper Clad Laminate). Specifically, the copper-clad laminate is formed by pressing the resin-coated copper foil onto at least one or both sides of various known copper foils or insulating sheets under heat. When laminating onto one side, a different material from the resin-coated copper foil may be pressed onto the other side. Furthermore, the number of resin-coated copper foils, copper foils, and insulating sheets in the copper-clad laminate is not particularly limited.

[0100] In one embodiment, the insulating sheet is preferably a prepreg or the support film. Prepreg refers to a sheet-like material in which a reinforcing material such as glass cloth is impregnated with a resin and cured to the B stage (JIS C 5603). The resin may be an insulating resin such as the polyimide resin (A) of the present invention, a phenolic resin, an epoxy resin, a polyester resin, a liquid crystal polymer, or an aramid resin. The thickness of the insulating sheet is preferably about 20 to 500 μm. Heating and pressing conditions are preferably about 150 to 280°C (more preferably about 170 to 240°C) and about 0.5 to 20 MPa (more preferably about 1 to 8 MPa).

[0101] [Printed wiring board] The printed wiring board of the present invention has a circuit pattern on the copper foil surface of the copper-clad laminate of the present invention. Patterning methods for forming a circuit pattern on the copper foil surface of the copper-clad laminate include subtractive and semi-additive methods. Semi-additive methods include patterning the copper foil surface of the copper-clad laminate with a resist film, electrolytic copper plating, removing the resist, and etching with an alkaline solution. The thickness of the circuit pattern layer in the printed wiring board is not particularly limited. A multilayer substrate can also be obtained by laminating the same printed wiring board or another known printed wiring board or printed circuit board on the printed wiring board as a core. During lamination, the resin composition can be used in combination with other known resin compositions. The number of layers in the multilayer substrate is not particularly limited. Via holes may be inserted and the interiors may be plated after each lamination. The line / space ratio of the circuit pattern is not particularly limited, but is preferably about 1 μm / 1 μm to 100 μm / 100 μm. The height of the circuit pattern is not particularly limited, but is preferably about 1 to 50 μm.

[0102] [Polyimide film] The polyimide film of the present invention is a cured product of the polyimide resin of the present invention.

[0103] The method for producing the polyimide film of the present invention includes coating the polyimide resin on the support, curing the polyimide resin by heating to form a polyimide resin layer, and peeling the support from the polyimide resin layer.

[0104] The polyimide resin can be applied to a support by the above-mentioned coating method, and the heat treatment conditions include, for example, heating at a temperature of about 100 to 180°C for about 0.5 to 3 hours.

[0105] The thickness of the polyimide resin layer after the heat treatment is preferably about 1 to 50 μm after drying.

[0106] The polyimide resin used in the polyimide film of the present invention may contain various additives, as long as they do not impair the effects of the present invention, such as a dehydrating agent, a plasticizer, a weathering agent, an antioxidant, a heat stabilizer, a lubricant, an antistatic agent, a brightener, a colorant, a conductive agent, a release agent, a surface treatment agent, a viscosity modifier, an inorganic filler, an inorganic pigment, and an organic pigment.

[0107] Examples of inorganic fillers include silica fillers, phosphorus-based fillers, fluorine-based fillers, and inorganic ion exchange fillers. Silica fillers whose surfaces have been modified with a treatment agent such as a silane coupling agent may also be used. Commercially available inorganic fillers include "FB-3SDC" and "SFP-20M" (all manufactured by Denka Co., Ltd.), "SC-2500-SPJ," "SC-2500-SXJ," "SC-2500-SVJ," and "SC-2500-SEJ" (all manufactured by Admatechs Co., Ltd.), "Exolit OP935" (manufactured by Clariant Chemicals Co., Ltd.), "KTL-500F" (manufactured by Kitamura Co., Ltd.), and "IXE" (manufactured by Toagosei Co., Ltd.).

[0108] Examples of inorganic pigments include cadmium red, cadmium lemon yellow, cadmium yellow orange, titanium dioxide, carbon black, black iron oxide, and black complex inorganic pigments.

[0109] Examples of organic pigments include aniline black, perylene black, anthraquinone black, benzidine-based yellow pigments, phthalocyanine blue, and phthalocyanine green.

[0110] The content of the additive in the polyimide resin of the present invention is preferably 1 to 150 parts by mass per 100 parts by mass of the component (A) (calculated as nonvolatile content). [Example]

[0111] The present invention will be described in more detail below with reference to examples, but is not limited to these. Unless otherwise specified, all "%" is by mass.

[0112] <Weight average molecular weight> The weight average molecular weight of the polyimide resin was measured under the following conditions. (Measurement conditions) Model: Product name "HLC-8320GPC" (manufactured by Tosoh Corporation) Column: Product name "TSKgel SuperHZM-M" (manufactured by Tosoh Corporation) Developing solvent: tetrahydrofuran Flow rate: 0.35mL / min Measurement temperature: 40℃ Detector: RI Standard: Polystyrene Sample concentration: 0.4 wt%

[0113] Example 1 A reaction vessel equipped with a stirrer, a water divider, a thermometer, and a nitrogen gas inlet tube was charged with 40.00 g of tetracarboxylic acid anhydride (trade name "ISS-TME", manufactured by Honshu Chemical Co., Ltd.) (hereinafter referred to as ISS-TME) having the structure shown in the following paragraph and 181.24 g of cyclohexanone, and heated to 60°C. Next, 41.64 g of dimer diamine (trade name "PRIAMINE 1075", manufactured by Croda Japan Co., Ltd.; hereinafter referred to as PRIAMINE 1075) was gradually added, followed by the addition of 30.21 g of methylcyclohexane. The imidization reaction was carried out at 140°C for 8 hours, yielding a solution of polyimide resin (A-1) with a weight average molecular weight of 30,000 (non-volatile content 30%).

[0114] [ka]

[0115] Example 2 40.00 g of ISS-TME and 152.45 g of cyclohexanone were charged into a reaction vessel similar to that used in Example 1 and heated to 60° C. Next, 42.45 g of PRIAMINE 1075 was gradually added, followed by the addition of 30.49 g of methylcyclohexane, and the imidization reaction was carried out at 140° C. for 8 hours to obtain a solution of polyimide resin (A-2) having a weight-average molecular weight of 36,000 (non-volatile content 30%).

[0116] Comparative Example 1 A reaction vessel similar to that used in Example 1 was charged with 210.00 g of 3,3',4,4'-benzophenonetetracarboxylic dianhydride (trade name: "BTDA", manufactured by Daicel Chemical Industries, Ltd.), 1006.32 g of cyclohexanone, and 201.26 g of methylcyclohexane, and the mixture was heated to 60°C. Next, 340.02 g of PRIAMINE 1075 was gradually added, and the imidization reaction was carried out at 120°C for 14 hours to obtain a solution of polyimide resin (A'-1) having a weight-average molecular weight of 37,000 (non-volatile content: 30%).

[0117] Comparative Example 2 In a reaction vessel similar to that used in Example 1, 320.00 g of 4,4'-[propane-2,2-diylbis(1,4-phenyleneoxy)]diphthalic dianhydride (trade name "BisDA-1000", manufactured by SABIC Innovative Plastics Japan, LLC) and 876.82 g of cyclohexanone were charged and heated to 60 ° C. Next, 212.18 g of PRIAMINE 1075 and 26.30 g of 1,3-bisaminomethylcyclohexane (manufactured by Mitsubishi Gas Chemical Company, Inc.) were gradually added, followed by the addition of 262.99 g of 1,2-dimethoxyethane and 146.09 g of methylcyclohexane. The imidization reaction was carried out at 120 ° C. for 20 hours to obtain a solution of polyimide resin (A'-2) with a weight average molecular weight of 37,000 (non-volatile content 30%).

[0118] Comparative Example 3 Into a reaction vessel similar to that used in Example 1, 65.00 g of p-phenylene bis(trimellitate anhydride) (manufactured by Manac Corporation) and 247.56 g of cyclohexanone were charged and heated to 60°C. Next, 68.88 g of PRIAMINE 1075 was gradually added, followed by the addition of 49.51 g of methylcyclohexane, and the imidization reaction was carried out at 140°C for 5 hours, but the reaction solution gelled and no polyimide resin was obtained.

[0119] <Preparation of evaluation sample (1)> The polyimide resin of Example 1 was coated onto a release paper (manufactured by San-A Kaken Co., Ltd.), dried at 150°C for 5 minutes, then at 170°C for 30 minutes, and the release paper was then peeled off to obtain a polyimide film with a thickness of 25 μm. Two of these films were laminated and melted by a heat press at 120°C to prepare evaluation sample (1). Evaluation samples (1) were also prepared in the same manner for the polyimide resins of Example 2 and Comparative Examples 1 to 3.

[0120] <Breaking elongation and elastic modulus> Each of the evaluation samples (1) cut to 5 mm x 40 mm was placed in a Tensilon universal testing machine (model name: "RTC-1250A", manufactured by Orientec Co., Ltd.), and a tensile test was performed at a spacing of 20 mm and a tensile speed of 5 mm / min to measure the stress at break (MPa) and the elongation at break (%). The modulus of elasticity was calculated by determining the slope of the curve consisting of stress and strain. In both cases, the higher the numerical value, the better the results. The results are shown in Table 1.

[0121] [Table 1]

[0122] The abbreviations in Table 1 are as follows: <Tetracarboxylic acid anhydride> ·a-1: Product name “ISS-TME”, manufactured by Honshu Chemical Co., Ltd. BTDA: 3,3',4,4'-benzophenonetetracarboxylic dianhydride, trade name: "BTDA", manufactured by Daicel Chemical Industries, Ltd. BisDA: 4,4'-[propane-2,2-diylbis(1,4-phenyleneoxy)]diphthalic dianhydride, product name: "BisDA-1000", manufactured by SABIC Innovative Plastics Japan, LLC TAHQ: p-phenylenebis(trimellitate anhydride), manufactured by Manac Corporation <Diamine> DDA: Dimer diamine, product name: "PRIAMINE 1075", manufactured by Croda Japan Co., Ltd. 1,3-BAC: 1,3-bisaminomethylcyclohexane, manufactured by Wakayama Seika Kogyo Co., Ltd.

[0123] <Preparation of Resin Composition> Evaluation example 1 233.3 g of polyimide resin (A-1) (70.0 g of nonvolatile content), 30.0 g of epoxy resin (trade name: "jER630", manufactured by Mitsubishi Chemical Corporation) as a crosslinker (30.0 g of nonvolatile content), and 136.7 g of cyclopentanone as an organic solvent were mixed and stirred thoroughly to obtain a resin composition with a nonvolatile content of 25%.

[0124] Evaluation example 2, comparative evaluation examples 1 and 2 The same method as in Evaluation Example 1 was carried out using each of the polyimide resins shown in Table 2, to obtain resin compositions each having a non-volatile content of 25%.

[0125] <Relative permittivity and dielectric loss tangent> The resin composition of Evaluation Example 1 was coated on a release paper (manufactured by San-A Kaken Co., Ltd.), dried at 150°C for 5 minutes and then at 170°C for 30 minutes, and then the release paper was peeled off to obtain a polyimide film with a thickness of 25 μm. Two of these films were laminated and melted by a heat press at 120°C to prepare Evaluation Sample (2). Evaluation Sample (2) was also prepared in the same manner for the resin compositions of Evaluation Example 2 and Comparative Evaluation Examples 1 and 2.

[0126] Using a network analyzer (Keysight Technologies, device name: "P5003A") and a split post dielectric resonator (QWED) with a measurement frequency of 10.124 GHz, the resonant frequency and peak Q value of the resonator alone with nothing inserted were measured. Next, each of the evaluation samples (2) was cut into a size of 4 cm x 5 cm to prepare a test piece, which was then inserted into a resonator, and the resonance frequency and Q value were measured when the test piece was inserted. The dielectric constant (Dk) was calculated from the difference in resonance frequency between the resonator alone and when the test piece was inserted, and the dielectric loss tangent (Df) was calculated from the difference in Q value and the difference in resonance frequency between the resonator alone and when the test piece was inserted. The results are shown in Table 2.

[0127] <Breaking elongation and elastic modulus> The elongation at break and modulus of elasticity of each of the evaluation samples (2) were measured in the same manner as described in the previous paragraph. The results are shown in Table 2.

[0128] [Table 2] *1: The weight parts of each component represent the weight of the non-volatile content.

[0129] <Preparation of Resin Composition> Evaluation example 3 A resin composition with a nonvolatile content of 25% was prepared by mixing 250.0 g of polyimide resin (A-1) (75.0 g of nonvolatile content), 11.4 g of an epoxy resin (trade name: "jER828" manufactured by Mitsubishi Chemical Corporation) as a crosslinking agent (11.4 g of nonvolatile content), 13.5 g of an active ester curing agent (trade name: "HPC-8000-65MT" manufactured by DIC Corporation) (13.5 g of nonvolatile content), 0.10 g of an imidazole epoxy resin (trade name: "Curesol 2E4MZ-A" manufactured by Shikoku Chemicals Corporation) (0.10 g of nonvolatile content), and 125 g of cyclopentanone as an organic solvent. The mixture was thoroughly stirred to obtain a resin composition with a nonvolatile content of 25%.

[0130] Comparative evaluation example 3 A resin composition with a nonvolatile content of 25% was obtained in the same manner as in Evaluation Example 3, except that the polyimide resin (A'-1) was used instead.

[0131] Evaluation samples (3) were prepared in the same manner as above using the resin compositions of Evaluation Example 3 and Comparative Evaluation Example 3, and the dielectric constant, dielectric loss tangent, elongation at break, and modulus of elasticity of each obtained evaluation sample (3) were measured. The results are shown in Table 3.

[0132] [Table 3] *2: The weight parts of each component represent the weight of the non-volatile content.

[0133] <Preparation of adhesive sheet> The resin composition of Evaluation Example 1 was applied to a commercially available polyimide film (trade name: Kapton 100EN, film thickness: 25 μm, thermal expansion coefficient: 15 ppm / °C, manufactured by DuPont-Toray Co., Ltd.) (hereinafter referred to as Kapton) using a gap coater so that the dried thickness would be 25 μm, and then dried at 150°C for 5 minutes to obtain an adhesive sheet (Kapton / cured product layer). Adhesive sheets were also prepared in the same manner for the resin compositions of Evaluation Examples 2 and 3 and Comparative Evaluation Examples 1 to 3.

[0134] <Preparation of copper clad laminate> The cured layer side of the adhesive sheet (Kapton / cured layer) was placed on the mirror side of commercially available electrolytic copper foil (product name "F2-WS", manufactured by Furukawa Electric Co., Ltd.) (film thickness 18 μm) to produce a laminate (Kapton / cured layer / electrolytic copper foil). The foil was then placed on a pressing support, and hot-pressed from above with a support made of the same material at a pressure of 10 MPa and a temperature of 180°C for 30 seconds, followed by thermal curing at a temperature of 170°C for 30 minutes to produce a copper-clad laminate.

[0135] <Solder heat resistance test> The copper-clad laminates were left in a thermostatic chamber at a temperature of 23°C and a humidity of 50% for 24 hours, and then floated, copper foil side down, in a solder bath at 288°C to check for the presence of bubbles. No bubbles were observed in any of the copper-clad laminates.

Claims

1. A polyimide resin which is a reaction product of a group of monomers including a tetracarboxylic acid anhydride (a1) represented by formula (2) and a diamine (a2) including a dimer diamine: 【Chemistry 2】

2. 2. The polyimide resin according to claim 1, wherein the component (a2) further comprises an alicyclic diamine and / or an aromatic diamine.

3. A resin composition comprising the polyimide resin according to claim 1 or 2 and a crosslinking agent.

4. A cured product of the resin composition according to claim 3.

5. An adhesive sheet having the cured product according to claim 4 on at least one surface of a support film.

6. A resin-coated copper foil comprising the cured product according to claim 4 and a copper foil.

7. A copper-clad laminate comprising the resin-coated copper foil according to claim 6 and a copper foil or an insulating sheet.

8. A printed wiring board having a circuit pattern on the copper foil surface of the copper-clad laminate according to claim 7.

9. A polyimide film which is a cured product of the polyimide resin according to claim 1 or 2.

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