JP2023163314A - Polyimide resin, resin composition, cured product, adhesive sheet, resin-attached copper foil, copper-clad laminate, printed wiring board, and polyimide film - Google Patents

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

The present invention relates to polyimide resins, resin compositions, cured products, adhesive sheets, resin-coated copper foils, copper-clad laminates, printed wiring boards, and polyimide films.

Polyimide resin is generally a resin obtained by reacting a tetracarboxylic acid anhydride and a diamine, and has various performances such as heat resistance, adhesion, and mechanical properties. Therefore, it is 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.

Furthermore, in recent years, high-frequency electrical signals have been used to transmit and process large amounts of information at high speed, but since high-frequency signals are extremely susceptible to attenuation, the multilayer wiring board has also been designed to reduce transmission loss as much as possible. In this respect, polyimide resins having low dielectric properties (low dielectric constant, low dielectric loss tangent) are useful.

Such polyimide resins include resins containing tetracarboxylic acid residues and dimer acid-derived diamine residues for forming adhesive layers in metal-clad laminates having an insulating resin layer, an adhesive layer, and a metal layer. is known (Patent Document 1). Since the polyimide resin has an aromatic ring, it exhibits excellent solder heat resistance.

Furthermore, multilayer circuit boards such as flexible printed wiring boards and printed circuit boards are composed of conductors processed from insulating sheet layers, polyimide resin layers, copper foils, etc., and are used in bent portions. Therefore, such a substrate is required to have flexibility, and if this is insufficient, the conductor may crack, leading to disconnection. In order to improve flexibility, it is possible to increase elongation and elastic modulus, but the polyimide resin of Patent Document 1 has poor elongation and elastic modulus.

Japanese Patent Application Publication No. 2018-140544

An object of the present invention is to provide a polyimide resin that provides a cured product exhibiting high elongation and elastic modulus, and a resin composition containing the polyimide resin.

The present inventor focused on the structure of tetracarboxylic acid anhydride, and after intensive study, found that the above-mentioned problem could be solved, and completed the present invention. That is, the present invention provides the following.

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

2. The polyimide resin according to item 1 above, in which the component (a1) contains one represented by formula (2).

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

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

5. A cured product of the resin composition according to item 4 above.

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

7. A resin-coated copper foil comprising the cured product and copper foil according to item 5 above.

8. A copper-clad laminate comprising the resin-coated copper foil according to item 7 above, and a copper foil or an insulating sheet.

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

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

The polyimide resin of the present invention and the resin composition containing the resin exhibit high elongation and elastic modulus when cured. As a result, the cured product has flexibility, and disconnection due to conductor cracks can be prevented in resin-coated copper foil, copper-clad laminates, and printed wiring boards. Further, when producing the polyimide resin, the produced polyimide resin is easily dissolved in an organic solvent.

The polyimide resin of the present invention comprises a tetracarboxylic anhydride (a1) represented by the general formula (1) (hereinafter referred to as the (a1) component) and a diamine (a2) containing a dimer diamine (hereinafter referred to as the (a2) component). ) is a reactant of a group of monomers containing Hereinafter, the polyimide resin (A) will be referred to as component (A).

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

Component (a1) is a tetracarboxylic anhydride represented by the above-mentioned general formula (1).

When the general formula (1) has an ester group, appropriate hardness is imparted to the obtained component (A), and the cured product exhibits high elongation and elastic modulus. Further, when R has a saturated polycyclic heterocyclic structure having an oxygen atom in the ring, the generated component (A) becomes easily soluble in an organic solvent.

As a specific example of such component (a1), one represented by formula (2) is preferable because it further exhibits the above-mentioned effect.

In formula (2), the position where the ester group is bonded to the aromatic ring and the steric structure of the acid anhydride are not particularly limited. In addition, examples of commercially available products of formula (2) include "ISS-TME" (manufactured by Honshu Kagaku Co., Ltd.).

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

Further, the monomer group may include a tetracarboxylic anhydride (a1-1) other than the component (a1) (hereinafter referred to as the component (a1-1)). As the component (a1-1), for example, 2,2',3,3'-biphenyltetracarboxylic dianhydride, 2,3',3,4'-biphenyltetracarboxylic dianhydride, 3,3 ',4,4'-biphenyltetracarboxylic dianhydride, pyromellitic dianhydride, 1,2,3,4-benzenetetracarboxylic anhydride, 3,3',4,4'-diphenylsulfone tetra Carboxylic dianhydride, 4,4'-oxydiphthalic anhydride, 4,4'-[propane-2,2-diylbis(1,4-phenyleneoxy)]diphthalic dianhydride, 2,2',3 , 3'-benzophenone tetracarboxylic dianhydride, 2,3,3',4'-benzophenone tetracarboxylic dianhydride, 3,3',4,4'-benzophenone tetracarboxylic 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, 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 Anhydride, bis(3,4-dicarboxyphenoxyphenyl)sulfone dianhydride, 1,4,5,8-naphthalenetetracarboxylic anhydride, 2,3,6,7-naphthalenetetracarboxylic anhydride, 2 , 3,6,7-anthracenetetracarboxylic dianhydride, 1,2,5,6-naphthalenetetracarboxylic dianhydride, 1,4,5,8-naphthalenetetracarboxylic dianhydride, 2,3 , 6,7-naphthalenetetracarboxylic dianhydride, 4,8-dimethyl-1,2,3,5,6,7-hexahydronaphthalene-1,2,5,6-tetracarboxylic dianhydride, Examples include 2,2-bis(3,4-dicarboxyphenyl)hexafluoropropane dianhydride, 2,2-bis(3,3',4,4'-tetracarboxyphenyl)tetrafluoropropane dianhydride, etc. It will be done. These may be used alone or in combination of two or more.

The amount of component (a1-1) used in 100 mol% of the monomer group constituting component (A) is not particularly limited, and is usually 40 mol% or less, preferably 20 mol% or less, and more preferably, Preferably it is 10 mol% or less.

The amount of component (a1-1) used in 100 mol% of component (a1) is not particularly limited, and is usually 80 mol% or less, preferably 40 mol% or less, and more preferably 20 mol%. It is as follows.

Component (a2) is a diamine including dimer diamine.

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

The dimer diamine described above is not particularly limited, and examples thereof include those represented by the following general formula (3). In general formula (3), m+n=6 to 17 is preferable, p+q=8 to 19 is preferable, and the broken line portion means a carbon-carbon single bond or a carbon-carbon double bond.

In addition, commercial products of dimer diamine include "Versamine 551", "Versamine 552" (all manufactured by Cognix Japan Co., Ltd.), "PRIAMINE1073", "PRIAMINE1074", and "PRIAMINE1075" (all manufactured by Croda Japan Co., Ltd.). (manufactured by), etc.

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

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

Further, the amount of dimer diamine used in 100 mol% of component (a2) is not particularly limited, and is usually 10 mol% or more, preferably 30 to 100 mol%.

Furthermore, the component (a2) may include a diamine (a2-1) other than dimer diamine (hereinafter referred to as component (a2-1)). Component (a2-1) may include, for example, aliphatic diamine, alicyclic diamine, aromatic diamine, diamino ether, and diamino polysiloxane. Note that these amines exclude dimer diamine.

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

Examples of alicyclic diamines include diaminodicyclohexane, 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, isophoronediamine, and the like.

Examples of aromatic diamines include 2,2'-diaminobiphenyl, 3,3'-diaminobiphenyl, 4,4'-diaminobiphenyl, 2,2'-dimethyl-4,4'-diaminobiphenyl, and 2,2'-diaminobiphenyl. Diaminobiphenyl such as '-diethyl-4,4'-diaminobiphenyl, 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;
Phenyl diamines such as p-phenylene diamine and m-phenylene diamine;
Diaminodiphenylsulfides such as 3,3'-diaminodiphenylsulfide, 3,4'-diaminodiphenylsulfide, 4,4'-diaminodiphenylsulfide;
Diaminodiphenylsulfones such as 3,3'-diaminodiphenylsulfone, 3,4'-diaminodiphenylsulfone, 4,4'-diaminodiphenylsulfone;
Diaminobenzophenones such as 3,3'-diaminobenzophenone, 3,4'-diaminobenzophenone, and 4,4'-diaminobenzophenone;
Diaminodiphenylmethane such as 3,3'-diaminodiphenylmethane, 3,4'-diaminodiphenylmethane, 4,4'-diaminodiphenylmethane, bis[4-(3-aminophenoxy)phenyl]methane;
Diaminophenylpropanes such as 2,2-di(3-aminophenyl)propane, 2,2-di(4-aminophenyl)propane, 2-(3-aminophenyl)-2-(4-aminophenyl)propane;
2,2-di(3-aminophenyl)-1,1,1,3,3,3-hexafluoropropane, 2,2-di(4-aminophenyl)-1,1,1,3,3, Diaminophenylhexafluoropropane such as 3-hexafluoropropane, 2-(3-aminophenyl)-2-(4-aminophenyl)-1,1,1,3,3,3-hexafluoropropane;
1,1-di(3-aminophenyl)-1-phenylethane, 1,1-di(4-aminophenyl)-1-phenylethane, 1-(3-aminophenyl)-1-(4-aminophenyl )-1-phenylethane and other diaminophenyl phenylethanes;
1,3-bis(3-aminophenoxy)benzene, 1,3-bis(4-aminophenoxy)benzene, 1,4-bis(3-aminophenoxy)benzene, 1,4-bis(4-aminophenoxy) Bisaminophenoxybenzene such as benzene;
1,3-bis(3-aminobenzoyl)benzene, 1,3-bis(4-aminobenzoyl)benzene, 1,4-bis(3-aminobenzoyl)benzene, 1,4-bis(4-aminobenzoyl) Bisaminobenzoylbenzene such as benzene;
1,3-bis(3-amino-α,α-dimethylbenzyl)benzene, 1,3-bis(4-amino-α,α-dimethylbenzyl)benzene, 1,4-bis(3-amino-α, bis-aminodimethylbenzylbenzenes such as α-dimethylbenzyl)benzene and 1,4-bis(4-amino-α,α-dimethylbenzyl)benzene;
1,3-bis(3-amino-α,α-ditrifluoromethylbenzyl)benzene, 1,3-bis(4-amino-α,α-ditrifluoromethylbenzyl)benzene, 1,4-bis(3- Bisaminoditrifluoromethylbenzylbenzenes such as amino-α,α-ditrifluoromethylbenzyl)benzene, 1,4-bis(4-amino-α,α-ditrifluoromethylbenzyl)benzene;
Aminophenoxybiphenyl such as 4,4'-bis(3-aminophenoxy)biphenyl, 4,4'-bis(4-aminophenoxy)biphenyl, 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;
Aminophenoxy phenyl ethers such as bis[4-(3-aminophenoxy)phenyl]ether and bis[4-(4-aminophenoxy)phenyl]ether;
2,2-bis[4-(3-aminophenoxy)phenyl]propane, 2,2-bis[3-(3-aminophenoxy)phenyl]-1,1,1,3,3,3-hexafluoropropane , 2,2-bis[4-(4-aminophenoxy)phenyl]-1,1,1,3,3,3-hexafluoropropane and other aminophenoxyphenylpropanes;
1,3-bis[4-(3-aminophenoxy)benzoyl]benzene, 1,3-bis[4-(4-aminophenoxy)benzoyl]benzene, 1,4-bis[4-(3-aminophenoxy) bis(aminophenoxybenzoyl)benzene such as benzoyl]benzene, 1,4-bis[4-(4-aminophenoxy)benzoyl]benzene;
1,3-bis[4-(3-aminophenoxy)-α,α-dimethylbenzyl]benzene, 1,3-bis[4-(4-aminophenoxy)-α,α-dimethylbenzyl]benzene, 1, Bis(amino Phenoxy-α,α-dimethylbenzyl)benzene;
Bis[(aminoaryloxy)benzoyl]diphenyl ether such as 4,4'-bis[4-(4-aminophenoxy)benzoyl]diphenyl ether;
Bis(amino-α,α-dimethylbenzylphenoxy)benzophenone such as 4,4′-bis[4-(4-amino-α,α-dimethylbenzyl)phenoxy]benzophenone:
Bis[amino-α,α-dimethylbenzylphenoxy]diphenylsulfone such as 4,4′-bis[4-(4-amino-α,α-dimethylbenzyl)phenoxy]diphenylsulfone;
Bis[aminophenoxyphenoxy]diphenylsulfone such as 4,4'-bis[4-(4-aminophenoxy)phenoxy]diphenylsulfone;
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 include 1-(4-aminophenyl)-2,3-dihydro-1,3,3-trimethyl-1H-inden-5-amine and 9,9-bis(4-aminophenyl)fluorene.

Examples of diaminoether 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, triethylene glycol bis(3-aminopropyl) ether, and the like.

Examples of the diaminopolysiloxane include α,ω-bis(2-aminoethyl)polydimethylsiloxane, α,ω-bis(3-aminopropyl)polydimethylsiloxane, and α,ω-bis(4-aminobutyl)polydimethylsiloxane. Dimethylsiloxane, α,ω-bis(5-aminopentyl)polydimethylsiloxane, α,ω-bis[3-(2-aminophenyl)propyl]polydimethylsiloxane, α,ω-bis[3-(4-amino) phenyl)propyl]polydimethylsiloxane and the like.

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

The amount of component (a2-1) used in 100 mol% of the monomer group constituting component (A) is not particularly limited, and is usually 90 mol% or less, preferably 50 mol% or less.

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

Component (A) of the present invention can be obtained by various known production methods. As for the manufacturing method, for example, a monomer group containing components (a1) and (a2) is heated at a temperature of preferably about 30 to 120°C, more preferably about 60 to 100°C, and for a time of preferably 0.1 to 100°C. A step of performing a polyaddition reaction for about 2 hours, more preferably about 0.1 to 0.5 hours to obtain a polyadduct, and heating the obtained polyadduct to a temperature of preferably about 80 to 250°C, more preferably 100 to 250°C. Examples include a method including a step of carrying out an imidization reaction, that is, a dehydration ring-closing reaction, at a temperature of about 170° C., preferably for about 0.5 to 50 hours, more preferably for about 1 to 20 hours. Note that the method and order of mixing the components (a1) and (a2) are not particularly limited.

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.

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. Further, examples of the dehydrating agent include aliphatic carboxylic acid anhydrides such as acetic anhydride and aromatic carboxylic acid anhydrides such as benzoic anhydride.

Examples of organic solvents include N-methyl-2-pyrrolidone, N,N-dimethylformamide, N,N-diethylformamide, N,N-dimethylacetamide, N,N-diethylacetamide, diazabicycloundecene, etc. Nitrogen-based organic solvent;
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, di-n-propyl ketone, etc. Aliphatic ketones;
Alicyclic ketones such as cyclopropyl methyl ketone, cyclobutanone, cyclobutyl methyl ketone, cyclopentanone, cyclohexanone, methylcyclohexanone;
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 , aliphatic esters such as methyl propionate, ethyl propionate, n-propyl propionate, isopropyl propionate, n-butyl propionate;
Alkyl carbonate esters such as dimethyl carbonate, ethyl methyl carbonate, diethyl carbonate;
Alicyclic esters such as methyl cyclopropanecarboxylate, ethyl cyclopropanecarboxylate, methyl cyclobutanecarboxylate;
Ethyl-n-propyl ether, di-n-propyl ether, diisopropyl ether, 1,2-dimethoxyethane, 1,1-diethoxyethane, 1,2-diethoxyethane, 1,2-dimethoxypropane, 2,2- Aliphatic ethers such as dimethoxypropane, 1,1-diethoxypropane, 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, t-butyl alcohol;
2-Methylpentane, 3-ethylpentane, n-hexane, 2-methylhexane, 3-methylhexane, 3-ethylhexane, n-heptane, 2-methylheptane, 3-methylheptane, 4-methylheptane, 3- Aliphatic hydrocarbons such as ethylheptane, n-octane, 2-methyloctane, 3-methyloctane, 4-methyloctane;
Methylcyclopentane, ethylcyclopentane, n-propylcyclopentane, isopropylcyclopentane, n-butylcyclopentane, isobutylcyclopentane, cyclohexane, methylcyclohexane, ethylcyclohexane, 1,1-dimethylcyclohexane, 1-ethyl-3-methyl Alicyclic hydrocarbons such as cyclohexane and cycloheptane;
Aromatic hydrocarbons such as benzene, toluene, and xylene; dimethyl sulfoxide, and the like. These may be used alone or in combination of two or more.

Further, the amount of the organic solvent used is adjusted so that the reaction concentration is 5 to 60% by weight, preferably 20 to 50% by weight.

The imide ring closure rate of component (A) is preferably about 90 to 100%, more preferably about 95 to 100%, from the viewpoint of obtaining component (A) with high softening point and high flexibility.
It is presumed that because the imide ring closure ratio of component (A) is within the above range, component (A) is likely to form a structure of hard segments and soft segments, and its softening point and flexibility are both high. The term "imide ring closure rate" as used herein means the content of cyclic imide bonds in the polyimide resin of component (A), and can be determined by various spectroscopic means such as NMR and IR analysis.

As for the physical properties of component (A), for example, the weight average molecular weight is preferably 10,000 to 100,000. Further, 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).

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

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

The content of the polyimide resin in the resin composition of the present invention is preferably about 5 to 95% by mass, more preferably about 50 to 90% by mass, with the nonvolatile content of the resin composition being 100% by mass.

The crosslinking agent is not particularly limited as long as it functions as a crosslinking agent for polyimide resin. Examples of the crosslinking agent include epoxy resin, benzoxazine, bismaleimide, cyanate ester, polyisocyanate, trimer triamine, and the like. These may be used alone or in combination of two or more.

Examples of the epoxy resin include phenol novolac type epoxy resin, cresol novolac type epoxy resin, bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, hydrogenated bisphenol A type epoxy resin, and hydrogenated bisphenol F type epoxy resin. Epoxy resin, stilbene type epoxy resin, triazine skeleton-containing epoxy resin, fluorene skeleton-containing epoxy resin, linear aliphatic epoxy resin, alicyclic epoxy resin, glycidylamine type epoxy resin, triphenolmethane type epoxy resin, alkyl-modified triphenol Methane type epoxy resin, biphenyl type epoxy resin, dicyclopentadiene skeleton-containing epoxy resin, naphthalene skeleton-containing epoxy resin, arylalkylene type epoxy resin, tetraglycidyl xylylene diamine, dimer acid modified epoxide which is a dimer acid modified product of the above epoxide, Examples include dimer acid diglycidyl ester. In addition, commercially available epoxy resins include "jER828", "jER834", "jER807", "jER604", "jER630", "jER871", "jER872" (manufactured by Mitsubishi Chemical Corporation), and "ST". -3000'', ``YD-172-X75'' (manufactured by Nippon Steel Chemical & Materials Co., Ltd.), ``Celoxide 2021P'' (manufactured by Daicel Corporation), ``TETRAD-X'' (manufactured by Mitsubishi Gas Chemical Co., Ltd.), Examples include "Sansocizer E-2000H" (manufactured by Shin Nihon Rika Co., Ltd.), "NC-513", "NC-514S", "NC-547" (manufactured by Cardolite Corp.), and the like. Among these, bisphenol A epoxide, bisphenol F epoxide, hydrogenated bisphenol A epoxide, and alicyclic epoxide are preferred from the viewpoint of the balance between soldering heat resistance and low dielectric properties.

Furthermore, when using an epoxy resin as a crosslinking agent, various known curing agents for epoxy resins and active ester curing agents can be used in combination. These curing agents may be used alone or in combination of two or more.

Examples of curing agents for epoxy resins include succinic anhydride, phthalic anhydride, maleic anhydride, trimellitic anhydride, pyromellitic anhydride, hexahydrophthalic anhydride, 3-methylhexahydrophthalic anhydride, 4-methyl- Hexahydrophthalic anhydride, mixture of 4-methylhexahydrophthalic anhydride and hexahydrophthalic anhydride, tetrahydrophthalic anhydride, methyl-tetrahydrophthalic anhydride, nadic anhydride, methylnadic anhydride, norbornane-2,3-dicarboxylic anhydride Acid anhydride curing agents such as acid anhydride, methylnorbornane-2,3-dicarboxylic anhydride, methylcyclohexenedicarboxylic anhydride, 3-dodecenylsuccinic anhydride, octenylsuccinic anhydride;
Dicyandiamide (DICY), aromatic diamines (“Lonzacure M-DEA”, “Lonzacure M-DETDA” (manufactured by Lonza Japan Co., Ltd.), etc.), aliphatic amines (“Vegechem Green V140”, “Vegechem Green”, etc.) Amine curing agents such as "V150" and "Vejichem Green G747" (manufactured by Tsukino Foods Co., Ltd.);
Phenol novolac resin, cresol novolac resin, bisphenol A type novolac resin, triazine-modified phenol novolac resin, phenolic hydroxyl group-containing phosphazene ("SPH-100" (manufactured by Otsuka Chemical Co., Ltd.), "NX-9001LP", "NX-9006" ”, “NX-9201LP” (manufactured by Cardolite Corp.), etc.);
Rosin-based curing agents such as maleic acid-modified rosin and its hydride;
Examples include cyclic phosphazene compounds.

Examples of active ester curing agents include those containing a dicyclopentadienyl diphenol structure described in JP 2019-183071, those containing a naphthalene structure, acetylated products of phenol novolak, benzoylated products of phenol novolak, etc. It will be done.
Commercially available active ester curing agents include, for example,
Those containing dicyclopentadienyl diphenol structure, "EXB9451", "EXB9460", "EXB9460S", "HPC-8000", "HPC-8000H", "HPC-8000-65T", "HPC-8150-"62T","HPC-8000H-65MT","HPC-8000L-65MT","EXB-8000L","EXB-8000L-65MT","EXB-8150-65T" (all manufactured by DIC Corporation);
Contains a naphthalene structure, “EXB9416-70BK” (manufactured by DIC Corporation);
An acetylated product of phenol novolak, "DC808" (manufactured by Mitsubishi Chemical Corporation);
Benzoylated products of phenol novolak include "YLH1026", "YLH1030", "YLH1048" (manufactured by Mitsubishi Chemical Corporation), and the like.

As the active ester curing agent, those produced by various known methods can also be used, such as those produced by reacting a polyfunctional phenol compound and aromatic carboxylic acids described in Japanese Patent No. 5152445. Can be mentioned.

Among the curing agents, active ester curing agents and phenol curing agents, particularly active ester curing agents, are preferred. The amount of the curing agent used is preferably about 0.1 to 40% by weight, more preferably about 1 to 20% by weight, based on 100% by weight of the nonvolatile content of the resin composition.

Furthermore, when an epoxy resin and a curing agent for epoxy resin are used together as a crosslinking agent, a reaction catalyst can be further used in combination. Examples of reaction catalysts include 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, 2-heptadecylimidazole; tributylphosphine, methyldiphenylphosphine, triphenylphosphine, diphenylphosphine, phenylphosphine organic phosphines such as; and tetraphenylboron salts such as tetraphenylphosphonium tetraphenylborate, 2-ethyl-4-methylimidazole tetraphenylborate, and N-methylmorpholine tetraphenylborate. These may be used alone or in combination of two or more. Further, the amount of the reaction catalyst used is preferably about 0.01 to 5% by mass, based on 100% by mass of the nonvolatile content of the resin composition.

Examples of the benzoxazine include 6,6-(1-methylethylidene)bis(3,4-dihydro-3-phenyl-2H-1,3-benzoxazine), 6,6-(1-methylethylidene)bis (3,4-dihydro-3-methyl-2H-1,3-benzoxazine) and the like. In addition, a phenyl group, a methyl group, a cyclohexyl group, etc. may be bonded to the nitrogen of the oxazine ring. Commercial products of benzoxazine include "Benzoxazine Fa type", "Benzoxazine P-d type" (manufactured by Shikoku Kasei Co., Ltd.), and "RLV-100" (manufactured by Air Water Co., Ltd.). ) etc.

Examples of the bismaleimide include 4,4'-diphenylmethane bismaleimide, m-phenylene bismaleimide, bisphenol A diphenyl ether bismaleimide, and 3,3'-dimethyl-5,5'-diethyl-4,4'-diphenylmethane bismaleimide. , 4-methyl-1,3-phenylenebismaleimide, 1,6'-bismaleimide-(2,2,4-trimethyl)hexane, 4,4'-diphenyl ether bismaleimide, 4,4'-diphenylsulfone bismaleimide etc. In addition, commercially available bismaleimide products include "BAF-BMI" (manufactured by JFE Chemical Co., Ltd.), "BMI-1000H" (manufactured by Daiwa Kasei Kogyo Co., Ltd.), and "BMI-689" (manufactured by DESIGNER MOLECULES Inc.). ) etc.

Examples of the cyanate ester 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, diallyl bisphenol A cyanate ester, 4-phenylphenol cyanate ester, 1,1,1-tris(4-cyanatophenyl)ethane, 4-cumylphenol cyanate ester, 1,1-bis(4- Examples thereof include cyanatophenyl)ethane, 4,4'-bisphenol cyanate ester, and 2,2-bis(4-cyanatophenyl)propane. Furthermore, commercially available cyanate esters include "PRIMASET BTP-6020S" (manufactured by Lonza Japan Co., Ltd.).

Examples of polyisocyanates include straight chain fatty acids such as methylene diisocyanate, dimethylene diisocyanate, trimethylene diisocyanate, tetramethylene diisocyanate, pentamethylene diisocyanate, hexamethylene diisocyanate, heptamethylene diisocyanate, octamethylene diisocyanate, nonamethylene diisocyanate, and decamethylene diisocyanate. Group diisocyanates;
Branched aliphatic polyisocyanates such as trimethylbutylene diisocyanate, trimethylpentylene diisocyanate, trimethylhexamethylene diisocyanate;
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, hydrogen Alicyclic polyisocyanates such as dimethyldiphenylmethane diisocyanate and hydrogenated naphthalene diisocyanate;
Aromatic polyisocyanates such as xylylene diisocyanate, tolylene diisocyanate, phenylene diisocyanate, tetramethylxylylene diisocyanate, diphenylmethane diisocyanate, dimethyldiphenylmethane diisocyanate, m-tetramethylxylylene diisocyanate, naphthalene diisocyanate, and the like.

Furthermore, as the polyisocyanate, biuret, isocyanurate, allophanate, and adduct forms of the above-mentioned polyisocyanates can also be used. These polyisocyanates may be used alone or in combination of two or more.

Commercially available polyisocyanates include, for example,
The biuret bodies are "Duranate 24A-100", "Duranate 22A-75P", "Duranate 21S-75E" (all manufactured by Asahi Kasei Corporation), and "Desmodur N3200A" (all manufactured by Sumitomo Bayer Urethane Co., Ltd.). etc. are mentioned,
The isocyanurates include "Duranate TPA-100", "Duranate TKA-100", "Duranate MFA-75B", "Duranate MHG-80B" (manufactured by Asahi Kasei Corporation), and "Coronate HXR" (manufactured by Tosoh Corporation). ), "Takenate D-131N", "Takenate D204EA-1", "Takenate D-127N" (manufactured by Mitsui Chemicals Co., Ltd.), "VESTANAT T1890/100" (manufactured by Evonik Japan Co., Ltd.) etc. are mentioned,
Examples of allophanates include "Takenate D-178N" (manufactured by Mitsui Chemicals, Inc.),
Adduct bodies include "Duranate P301-75E" (manufactured by Asahi Kasei Corporation), "Takenate D110N", "Takenate D160N" (all manufactured by Mitsui Chemicals, Inc.), "Coronate L" (manufactured by Tosoh Corporation), etc. can be mentioned.

Trimer triamine is a trimer of unsaturated fatty acids such as oleic acid, linoleic acid, and linolenic acid (see Japanese Patent Application Publication No. 2013-505345), with all carboxyl groups replaced with primary amino groups. Various known ones can be used. Non-limiting examples of the structure include those described in JP-A No. 2017-186551 and the like.

Examples of commercially available trimer triamines include "PRIAMINE1071" (manufactured by Croda Japan Co., Ltd.). The content of trimer triamine in commercially available products is approximately 15 to 20% by mass, and the remainder may contain more than 80% by mass of dimer diamine.

The content of the crosslinking agent in the resin composition of the present invention is preferably about 1 to 900 parts by mass based on 100 parts by mass of component (A) in the resin composition (in terms of nonvolatile content).

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.

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

Examples of the phosphorus flame retardant include polyphosphoric acid, phosphoric acid ester, and phosphazene derivatives having no phenolic hydroxyl group. Among the phosphazene derivatives, cyclic phosphazene derivatives are preferred in terms of flame retardancy, heat resistance, bleed-out resistance, and the like. Commercially available cyclic phosphazene derivatives include "SPB-100" (manufactured by Otsuka Chemical Co., Ltd.) and "Rabitor FP-300B" (manufactured by Fushimi Pharmaceutical Co., Ltd.).

Examples of the inorganic filler include silica filler, phosphorus filler, fluorine filler, and inorganic ion exchange filler. Note that the silica filler may be one whose surface has been modified with a treatment agent such as a silane coupling agent. In addition, commercially available inorganic fillers include "FB-3SDC", "SFP-20M" (manufactured by Denka Corporation), "SC-2500-SPJ", "SC-2500-SXJ", "SC- 2500-SVJ", "SC-2500-SEJ" (manufactured by Admatex Co., Ltd.), "Exolit OP935" (manufactured by Clariant Chemicals Co., Ltd.), "KTL-500F" (manufactured by Kitamura Co., Ltd.), " IXE" (manufactured by Toagosei Co., Ltd.).

The content of the flame retardant in the resin composition of the present invention is preferably 1 to 150 parts by mass based on 100 parts by mass (in terms of nonvolatile content) of component (A) in the resin composition.

The content of the flame retardant in the resin composition of the present invention is preferably about 1 to 75% by mass, with the nonvolatile content of the resin composition being 100% by mass.

The resin composition of the present invention has a general formula: W-Si(R ¹ ) _a (OR ² ) _3-a (wherein, W is a group containing a functional group that reacts with an acid anhydride group, and R ¹ is a group containing a functional group that reacts with an acid anhydride group. Hydrogen or a hydrocarbon group having 1 to 8 carbon atoms, R ² is a hydrocarbon group having 1 to 8 carbon atoms, and a is 0, 1 or 2). good. The reactive alkoxysilyl compound allows the melt viscosity of the resin composition layer to be adjusted while maintaining low dielectric properties. As a result, the interfacial adhesion (so-called anchor effect) between the layer of the resin composition and the support can be enhanced, while the bleeding of the cured layer from the edges of the support can be suppressed.

Examples of the reactive functional group included in W in the general formula include an amino group, an epoxy group, and a thiol group.

Compounds in which W contains an amino group include N-2-(aminoethyl)-3-aminopropylmethyldimethoxysilane, N-2-(aminoethyl)-3-aminopropyltrimethoxysilane, and 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, and 3-glycidoxypropyltrimethoxysilane. Examples include sidoxypropylmethyldiethoxysilane and 3-glycidoxypropyltriethoxysilane. Examples of the compound 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 they have good reactivity and flow control effects.

The content of the reactive alkoxysilyl compound in the resin composition of the present invention is 0.01 to 5 parts by mass based on 100 parts by mass (in terms of nonvolatile content) of the component (A) of the present invention in the resin composition. preferable.

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.

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.

Additives include ring-opening esterification reaction catalyst, dehydrating agent, plasticizer, weathering agent, antioxidant, heat stabilizer, lubricant, antistatic agent, brightener, coloring agent, conductive agent, mold release agent, and surface treatment. agent, viscosity modifier, silica filler, fluorine filler, etc.

The content of the additive may be less than 1% by mass, less than 0.1% by mass, less than 0.01% by mass, 0% by mass, etc., based on 100% by mass of nonvolatile content of the resin composition.

The content of the additive is less than 1 part by mass, less than 0.1 part by mass, less than 0.01 part by mass, and 0 part by mass with respect to 100 parts by mass of component (A) in the resin composition (in terms of nonvolatile content). Departments, etc.

The resin composition of the present invention can be obtained by dissolving the crosslinking agent and, if necessary, the flame retardant, reactive alkoxysilyl compound, and additives in the polyimide resin of the present invention. In addition, in preparing the resin composition, the above-mentioned organic solvent may be further blended.

[Cured product]
The present invention also includes a cured product of the resin composition. The method for producing the cured product includes a method including a step of coating the resin composition on a suitable support, a step of curing by heating to volatilize the organic solvent, a step of peeling off the support, etc. Can be mentioned. Further, 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. Furthermore, when producing a cured product, the resin composition and various known resin compositions other than the resin composition may be used in combination.

[Adhesive sheet]
The adhesive sheet of the present invention contains the cured product of the present invention on at least one side of the support film.

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

The support film is made of polyimide, polyester, polyimide-silica hybrid, polyethylene, polypropylene, polyethylene terephthalate, polyethylene naphthalate, polymethyl methacrylate resin, polystyrene resin, polycarbonate resin, acrylonitrile-butadiene-styrene resin, ethylene terephthalate, phenol, phthalate. Aromatic polyester resins obtained from acids, hydroxynaphthoic acid, etc. and parahydroxybenzoic acid (so-called liquid crystal polymers; "Vexter" (manufactured by Kuraray Co., Ltd.), etc.), cycloolefin polymers, fluorine-based resins (polytetrafluoroethylene (PTFE), perfluoroalkoxyalkane (PFA), polyvinylidene fluoride (PVDF), etc.). Polyimide includes the polyimide film of the present invention.

When coating the resin composition of the present invention on the support film, examples of the coating method include comma, die, knife, lip, and other coaters. The thickness of the coating layer after drying is preferably about 1 to 100 μm, more preferably about 3 to 50 μm. Moreover, the cured material layer of the adhesive sheet may be protected with various protective films.

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

The thickness of the copper foil is preferably about 1 to 100 μm, more preferably about 2 to 38 μm. In addition, examples of the coating means include the methods described above.

Further, the resin composition layer or cured product of the resin-coated copper foil may be partially or completely cured under heating. The partially cured resin composition layer or cured product is in a so-called B stage state. Further, the thickness of the resin composition layer or cured product is preferably about 0.5 to 30 μm. Further, a resin can be further bonded to the copper foil of the resin-coated copper foil to obtain a double-sided resin-coated copper foil.

[Copper-clad laminate]
The copper-clad laminate of the present invention includes the resin-coated copper foil and the copper foil or the insulating sheet of the present invention. A copper clad laminate is also called CCL (Copper Clad Laminate). Specifically, the copper-clad laminate is made 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 pasting on one side, a material different from the resin-coated copper foil may be crimped onto the other side. Further, the number of resin-coated copper foils, copper foils, and insulating sheets in the copper-clad laminate is not particularly limited.

In one embodiment, the insulating sheet is preferably a prepreg or the support film described above. Prepreg is a sheet-like material made by impregnating a reinforcing material such as glass cloth with resin and curing it to B stage (JIS C 5603). As the resin, an insulating resin such as the polyimide resin (A) of the present invention, phenol resin, epoxy resin, polyester resin, liquid crystal polymer, or aramid resin is used. The thickness of the insulating sheet is preferably about 20 to 500 μm. The heating/pressing conditions are preferably about 150 to 280°C (more preferably about 170 to 240°C), and preferably about 0.5 to 20 MPa (more preferably about 1 to 8 MPa).

[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. Examples of patterning methods for forming a circuit pattern on the copper foil surface of a copper-clad laminate include a subtractive method and a semi-additive method. Examples of the semi-additive method include a method in which the copper foil surface of the copper-clad laminate is patterned with a resist film, electrolytic copper plating is performed, the resist is removed, and etching is performed with an alkaline solution. Moreover, the thickness of the circuit pattern layer in the printed wiring board is not particularly limited. Moreover, a multilayer board can also be obtained by using the printed wiring board as a core and laminating the same printed wiring board or other known printed wiring boards or printed circuit boards thereon. At the time of lamination, the above-mentioned resin composition and other known resin compositions other than the above-mentioned resin composition can be used together. Furthermore, the number of layers in the multilayer substrate is not particularly limited. Alternatively, a via hole may be inserted each time the layers are laminated, and the inside may be plated. 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 also not particularly limited, but is preferably about 1 to 50 μm.

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

The method for producing the polyimide film of the present invention includes coating the polyimide resin on the support, curing it by heating to form a polyimide resin layer, and peeling off the support from the polyimide resin layer. can be mentioned.

Examples of the method for coating the polyimide resin on the support include the above-mentioned coating means. Further, the heat treatment conditions include, for example, a method of heating at a temperature of about 100 to 180° C. for about 0.5 to 3 hours.

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

The polyimide resin used in the polyimide film of the present invention may contain various additives as long as the effects of the present invention are not impaired. The additives include dehydrating agents, plasticizers, weathering agents, antioxidants, heat stabilizers, lubricants, antistatic agents, whitening agents, coloring agents, conductive agents, mold release agents, surface treatment agents, viscosity modifiers, Examples include inorganic fillers, inorganic pigments, and organic pigments.

Examples of the inorganic filler include silica filler, phosphorus filler, fluorine filler, and inorganic ion exchange filler. Note that the silica filler may be one whose surface has been modified with a treatment agent such as a silane coupling agent. In addition, commercially available inorganic fillers include "FB-3SDC", "SFP-20M" (manufactured by Denka Corporation), "SC-2500-SPJ", "SC-2500-SXJ", "SC- 2500-SVJ", "SC-2500-SEJ" (manufactured by Admatex Co., Ltd.), "Exolit OP935" (manufactured by Clariant Chemicals Co., Ltd.), "KTL-500F" (manufactured by Kitamura Co., Ltd.), " IXE" (manufactured by Toagosei Co., Ltd.).

Examples of the inorganic materials include cadmium red, cadmium lemon yellow, cadmium yellow orange, titanium dioxide, carbon black, black iron oxide, and black complex inorganic materials.

Examples of the organic pigment include aniline black, perylene black, anthraquinone black, benzidine yellow pigment, phthalocyanine blue, and phthalocyanine green.

The content of the additive in the polyimide resin of the present invention is preferably 1 to 150 parts by mass based on 100 parts by mass of component (A) (calculated as nonvolatile content).

Hereinafter, the present invention will be specifically explained with reference to Examples, but the present invention is not particularly limited thereto. Furthermore, unless otherwise specified, all "%" are based on mass.

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

Example 1
In a reaction vessel equipped with a stirrer, a water separator, a thermometer, and a nitrogen gas inlet tube, a tetracarboxylic acid anhydride (trade name "ISS-TME", manufactured by Honshu Kagaku Co., Ltd.) having the structure shown in the next paragraph ( 40.00 g of ISS-TME (hereinafter referred to as ISS-TME) and 181.24 g of cyclohexanone were charged and heated to 60°C. Next, 41.64 g of dimer diamine (trade name "PRIAMINE1075", manufactured by Croda Japan Co., Ltd., hereinafter referred to as PRIAMINE1075) was gradually added, and then 30.21 g of methylcyclohexane was added, and the mixture was heated at 140°C for 8 hours. By carrying out the imidization reaction, a solution (non-volatile content: 30%) of polyimide resin (A-1) having a weight average molecular weight of 30,000 was obtained.

Example 2
40.00 g of ISS-TME and 152.45 g of cyclohexanone were placed in the same reaction vessel as in Example 1, and heated to 60°C. Next, 42.45 g of PRIAMINE 1075 was gradually added, followed by 30.49 g of methylcyclohexane, and an imidization reaction was carried out at 140°C for 8 hours to form a polyimide resin (A-2) with a weight average molecular weight of 36,000. A solution (30% non-volatile content) was obtained.

Comparative example 1
In a reaction vessel similar to Example 1, 210.00 g of 3,3',4,4'-benzophenonetetracarboxylic dianhydride (trade name: "BTDA", manufactured by Daicel Chemical Industries, Ltd.) and cyclohexanone were added. 1006.32g and 201.26g of methylcyclohexane were charged and heated to 60°C. Next, after gradually adding 340.02 g of PRIAMINE1075, an imidization reaction was carried out at 120°C for 14 hours to obtain a solution (non-volatile content: 30%) of polyimide resin (A'-1) with a weight average molecular weight of 37,000. Obtained.

Comparative example 2
In a reaction vessel similar to Example 1, 4,4'-[propane-2,2-diylbis(1,4-phenyleneoxy)]diphthalic dianhydride (trade name "BisDA-1000", manufactured by SABIC Innovative Plastics) was added. 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 Co., Ltd.) were gradually added, and then 262.99 g of 1,2-dimethoxyethane and 146 g of methylcyclohexane were added. By adding 0.9 g to the solution and carrying out an imidization reaction at 120° C. for 20 hours, a solution (non-volatile content: 30%) of polyimide resin (A'-2) having a weight average molecular weight of 37,000 was obtained.

Comparative example 3
Into the same reaction vessel as in Example 1, 65.00 g of p-phenylene bis(trimelitate anhydride) (manufactured by Manac Co., Ltd.) 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 49.51 g of methylcyclohexane, and an imidization reaction was carried out at 140°C for 5 hours, but the reaction solution gelled and polyimide resin could not be obtained. .

<Preparation of evaluation sample (1)>
The polyimide resin of Example 1 was coated on release paper (manufactured by San-A Kaken Co., Ltd.) and dried at 150°C for 5 minutes and then at 170°C for 30 minutes, and then the release paper was peeled off to form a film with a thickness of 25 μm. A polyimide film was obtained. An evaluation sample (1) was prepared by laminating two such films and melting them using a hot press at 120°C. Evaluation samples (1) were similarly prepared for the polyimide resins of Example 2 and Comparative Examples 1 to 3, respectively.

<Elongation at break and elastic modulus>
Each evaluation sample (1) cut to 5 mm x 40 mm was set in a Tensilon universal testing machine (equipment name: "RTC-1250A", manufactured by Orientec Co., Ltd.), and the conditions were set at a spacing of 20 mm and a tensile speed of 5 mm/min. A tensile test was conducted, and the stress at cutting (MPa) and elongation at break (%) were measured. The elastic modulus was calculated by determining the slope of the curve consisting of stress and strain. In both cases, the higher the value, the better the result. The results are shown in Table 1.

The abbreviations in Table 1 are as follows.
<Tetracarboxylic acid anhydride>
・a-1: Product name "ISS-TME", manufactured by Honshu Kagaku Co., Ltd. ・BTDA: 3,3',4,4'-benzophenonetetracarboxylic dianhydride, product name: "BTDA", Daicel Chemical Industries, Ltd. Co., Ltd.)
・BisDA: 4,4'-[propane-2,2-diylbis(1,4-phenyleneoxy)]diphthalic dianhydride, trade name: "BisDA-1000", manufactured by SABIC Innovative Plastics Japan LLC ・TAHQ : p-phenylene bis (trimelitate anhydride), manufactured by Manac Co., Ltd. <Diamine>
・DDA: Dimer diamine, product name: "PRIAMINE1075", manufactured by Croda Japan Co., Ltd. ・1,3-BAC: 1,3-bisaminomethylcyclohexane, manufactured by Wakayama Seika Kogyo Co., Ltd.

<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 crosslinking agent (30.0 g of nonvolatile content), and By mixing 136.7 g of cyclopentanone as an organic solvent and stirring well, a resin composition with a nonvolatile content of 25% was obtained.

Evaluation example 2, comparative evaluation examples 1 and 2
Using the polyimide resins shown in Table 2, the same method as in Evaluation Example 1 was conducted to obtain resin compositions each having a non-volatile content of 25%.

<Relative permittivity and dielectric loss tangent>
The resin composition of Evaluation Example 1 was coated on release paper (manufactured by San-A Kaken Co., Ltd.) and dried at 150°C for 5 minutes and then at 170°C for 30 minutes, and then the release paper was peeled off to determine the film thickness. A 25 μm polyimide film was obtained. An evaluation sample (2) was prepared by laminating two of the films and melting them using a hot press at 120°C. Evaluation samples (2) were similarly prepared for the resin compositions of Evaluation Example 2 and Comparative Evaluation Examples 1 and 2, respectively.

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

<Elongation at break and elastic modulus>
The elongation at break and elastic modulus of each evaluation sample (2) were measured in the same manner as described in the previous paragraph. The results are shown in Table 2.

*1: Parts by weight of each component represent the weight of non-volatile content.

<Preparation of resin composition>
Evaluation example 3
250.0 g of polyimide resin (A-1) (75.0 g of nonvolatile content), 11.4 g of epoxy resin (product name: "jER828", manufactured by Mitsubishi Chemical Corporation) as a crosslinking agent (11.4 g of nonvolatile content), Active ester curing agent (product name: "HPC-8000-65MT", manufactured by DIC Corporation) 13.5g (nonvolatile content 13.5g), imidazole-based epoxy resin (product name: "Curezol 2E4MZ-A", Shikoku) (manufactured by Kasei Kogyo Co., Ltd.) (non-volatile content: 0.10 g) and 125 g of cyclopentanone as an organic solvent were mixed and thoroughly stirred to obtain a resin composition with a non-volatile content of 25%.

Comparative evaluation example 3
In 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 polyimide resin (A'-1) was used.

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

*2: Parts by weight of each component represent the weight of non-volatile content.

<Preparation of adhesive sheet>
The resin composition of Evaluation Example 1 was coated with a commercially available polyimide film (trade name: "Kapton 100EN", film thickness: 25 μm, coefficient of thermal expansion: 15 ppm/°C, manufactured by DuPont-Toray Co., Ltd.) (hereinafter referred to as Kapton). After coating with a gap coater so that the thickness after drying was 25 μm, it was dried at 150° C. for 5 minutes to obtain an adhesive sheet (Kapton/cured material layer). Adhesive sheets were similarly produced for the resin compositions of Evaluation Examples 2 and 3 and Comparative Evaluation Examples 1 to 3, respectively.

<Production of copper-clad laminate>
Layer the cured layer side of the adhesive sheet (Kapton/cured layer) on the mirror side of a commercially available electrolytic copper foil (product name "F2-WS", manufactured by Furukawa Electric Co., Ltd.) (film thickness 18 μm). A laminate (Kapton/cured material layer/electrolytic copper foil) was produced. Next, it was placed on a press support and heated from above through a support obtained from the same material at a pressure of 10 MPa and a temperature of 180°C for 30 seconds, and then heat-cured at a temperature of 170°C for 30 minutes. , a copper-clad laminate was produced.

<Solder heat resistance test>
After leaving the copper-clad laminate described above in a constant temperature room at 23°C and 50% humidity for 24 hours, it was floated with the copper foil side down in a 288°C solder bath to check for foaming. No foaming was observed in the copper-clad laminate.

Claims (10)

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.
(R in formula (1) represents a saturated polycyclic heterocyclic structure having an oxygen atom in the ring.) The polyimide resin according to claim 1, wherein component (a1) contains one represented by formula (2).
The polyimide resin according to claim 1 or 2, wherein component (a2) further contains an alicyclic diamine and/or an aromatic diamine. A resin composition comprising the polyimide resin according to any one of claims 1 to 3 and a crosslinking agent. A cured product of the resin composition according to claim 4. An adhesive sheet having the cured product according to claim 5 on at least one side of a support film. A resin-coated copper foil comprising the cured product according to claim 5 and the copper foil. A copper-clad laminate comprising the resin-coated copper foil according to claim 7 and a copper foil or an insulating sheet. A printed wiring board having a circuit pattern on the copper foil surface of the copper-clad laminate according to claim 8. A polyimide film which is a cured product of the polyimide resin according to any one of claims 1 to 3.