JP2006193576A - Polyimide resin composition - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a polyimide resin composition having excellent processability, adhesiveness and heat resistance. <P>SOLUTION: This polyimide resin composition comprises a polyimide obtained by reacting an acid component with a diamine component, and an isoimide oligomer containing a triple bond at the molecular terminal, and a cured product thereof. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention is a multilayer printed wiring board having high reliability, a polyimide resin composition useful as an interlayer insulating material capable of high-density wiring, and a heat-resistant adhesive obtained by using the resin composition, a varnish, The present invention relates to a film, a film laminate, a metal laminate, a prepreg, and a cured product thereof.

  In recent years, small electronic devices such as mobile phones, digital still cameras, and PDAs have become more functional, thinner, and lighter. Accordingly, electronic components and boards mounted on electronic devices have also become highly functional and highly functional. There has been a demand for higher performance and higher density. Specifically, multi-layer printed wiring boards capable of routing three-dimensional wiring by laminating printed wiring boards are being actively developed. For example, the B2 it method (abbreviation of Buried Bump Interconnection Technology) The known interlayer connection technology supports high density wiring (see, for example, Patent Document 1). That is, the copper foil with bumps and the uncured insulating layer are alternately laminated, pressed under a predetermined temperature and pressure condition, and the insulating layer is penetrated by the bump, whereby the lower wiring layer and the upper layer through the insulating layer Electrical connection with the wiring layer is provided as appropriate.

  In these techniques, it is necessary to reliably penetrate the insulating layer with the bump and to protrude the bump head from the insulating layer. In general, a polyimide film, a liquid crystal polymer film, a polyphenylene sulfide film, a polyether ether ketone film, an epoxy-modified polyimide, or the like is used as these interlayer insulating materials. However, polyimide films, liquid crystal polymer films, polyphenylene sulfide films, polyether ether ketone films, and the like have high lamination temperatures due to their high glass transition temperatures, and are difficult to use for general printed wiring boards. In addition, the “flow” of the resin is poor, and the bump deforms when the bump penetrates the insulating layer, and the bump height and the protrusion amount of the bump head are likely to vary. Protruding or filling the base of the bump with resin was not sufficient, and the conduction reliability and insulation reliability were insufficient.

  On the other hand, the thing which provided the difference of the glass transition temperature before and behind hardening like an epoxy modified polyimide is developed. However, since such a polyimide has thermoplastic properties even after being cured, when sequentially laminated, the lower wiring layer and the insulating layer are curved, and there is a possibility of poor insulation and poor conduction. It was.

  On the other hand, a composition containing an aromatic polymer and an acetylene-terminated aromatic substance has been reported (for example, see Patent Document 2). Specifically, polyetherimide (Ultem D-1000: manufactured by General Electronic Co., Ltd.) is mixed with acetylene-terminated polyisoimide (Thermid resin: manufactured by Kanebo Nenessec Co., Ltd.) to improve the solvent crack resistance of aromatic polymers. It has been reported that it is possible. However, these resin compositions have a glass transition temperature after curing of 200 ° C. or lower, lacking heat resistance for printed wiring board applications, and exhibiting solvent resistance properties unless cured for a long time. There is. In addition, a semi-interpenetrating polymer network produced from a combination of a polyisoimide having the same main chain structural unit and an imide oligomer having an unsaturated end group has been reported (for example, see Patent Document 3). However, since polyisoimide has a high viscosity when the degree of polymerization increases, it is difficult to filter dicyclohexylurea (DCU) by-produced from N, N′-dicyclohexylcarbodiimide (DCC), which is a dehydrating agent used for ring-closing reaction from polyamic acid. There are manufacturing problems such as Furthermore, from the viewpoint of environmental problems, it is essential to deal with lead-free solder, and the development of insulating materials with higher heat resistance is desired.

JP 2001-015920 A JP-T 62-501369 Japanese Patent Publication No. Hei 3-502110

  The object of the present invention is to provide excellent workability and adhesiveness before curing, and excellent heat resistance, adhesiveness and electrical properties after curing, especially polyimide resin suitable for interlayer insulation of multilayer printed wiring boards It is to provide a composition.

  In the present invention, the following general formula (1) obtained by reacting a tetracarboxylic dianhydride component A and a diamine component B in a range of 0.95 ≦ A / B <1.10:

(Wherein n is a number of 21 or more, Ar ₁ is a tetracarboxylic acid residue, and Ar ₂ is a diamine residue), and a polyimide containing a repeating unit represented by the following general formula (2):

(In the formula, i is a number of 0 to 20, Ar ₃ is a tetracarboxylic acid residue, Ar ₄ is a diamine residue, Ar ₅ is a monoamine residue, R ₁ is hydrogen or 1 to 1 carbon atoms. It is related with the polyimide resin composition characterized by including the isoimide oligomer represented by this by a weight ratio of 5 / 95-95 / 5.

  The polyimide resin composition of the present invention comprises a polyimide obtained by reacting a tetracarboxylic dianhydride component A mole and a diamine component B mole in a range of 0.95 ≦ A / B <1.10, and a molecular terminal. Is mixed with an isoimide oligomer containing a crosslinkable group (a group containing a carbon-carbon triple bond) in at least a part thereof to form an uncured film. By mixing the oligomer component, the glass transition temperature before curing of the polyimide resin composition of the present invention is greatly shifted to a lower temperature side than the glass transition temperature of the polyimide not mixed with the oligomer component. As a result, the resin composition of the present invention is in a high flow state and is in a state where it can be easily processed and bonded. That is, the resin composition of the present invention can be easily penetrated through the bump, filled with the resin at the base of the bump, and bonded in the temperature range from the glass transition temperature to the curing temperature. Then, a glass transition temperature of the cured product of the polyimide resin composition of the present invention is obtained by performing a heat treatment (curing treatment) at 180 to 450 ° C. to crosslink the crosslinkable group of the oligomer component linearly and / or three-dimensionally. Shifts to a higher temperature than the glass transition temperature of the polyimide not mixed with the oligomer component. As a result, the cured product of the resin composition of the present invention is excellent in heat resistance, adhesiveness, electrical characteristics and the like, and is particularly suitable for an interlayer insulating material for multilayer printed wiring boards.

  The polyimide resin composition of the present invention will be specifically described. First, the following general formula (1) obtained by reacting A mol of tetracarboxylic dianhydride component and B mol of diamine component in the range of 0.95 ≦ A / B <1.10 used in the present invention. :

(Wherein n is a number of 21 or more, Ar ₁ is a tetracarboxylic acid residue, and Ar ₂ is a diamine residue), a polyimide containing a repeating unit represented by a tetracarboxylic dianhydride component And a diamine component can be reacted and produced by a known method via imidation of the resulting polyamic acid.

  In the production of polyimide, first, a tetracarboxylic dianhydride component and a diamine component are reacted to produce a corresponding polyamic acid. The production of the polyamic acid is not particularly limited, except that the tetracarboxylic dianhydride component A mole and the diamine component B mole are reacted in the range of 0.95 ≦ A / B <1.10. It is usually done in a solvent. Here, in the production of the polyimide resin composition of the present invention, when the polyimide and the isoimide oligomer are mixed, if a free amino group is present at the end of the polyimide, it reacts with the isoimide ring, and the polyimide Undesirable gelation may occur in the composition. Therefore, the tetracarboxylic dianhydride component is preferably used in an equimolar amount or more, particularly in the range of 1.00 ≦ A / B <1.10.

For example, specific examples of the tetracarboxylic dianhydride used here (that is, those that form the tetracarboxylic acid residue of Ar ₁ ) include pyromellitic dianhydride, 3,3 ′, 4,4′- Biphenyltetracarboxylic dianhydride, 2,3 ′, 3,4′-biphenyltetracarboxylic dianhydride, 2,2 ′, 3,3′-biphenyltetracarboxylic dianhydride, 4,4′-oxydiphthalate Acid dianhydride, 3,4'-oxydiphthalic dianhydride, 3,3'-oxydiphthalic dianhydride, 4,4'-benzophenone tetracarboxylic dianhydride, 4,4'-diphenylsulfone tetracarboxylic acid Dianhydride, 2,2-bis (3,4-dicarboxyphenyl) propane dianhydride, 2,2-bis (3,4-dicarboxyphenyl) hexafluoropropane dianhydride, 1,2,7, 8-Naph Such as Ren tetracarboxylic acid dianhydride. In addition, it is desirable that the polyimide represented by the general formula (1) is soluble in a solvent, and therefore, depending on the type of aromatic diamine selected, 4,4′-oxydiphthalic dianhydride, 3,4 '-Oxydiphthalic dianhydride, 3,3'-oxydiphthalic dianhydride, 4,4'-benzophenone tetracarboxylic dianhydride, 4,4'-diphenylsulfone tetracarboxylic dianhydride, 2,2- The use of bis (3,4-dicarboxyphenyl) propane dianhydride, 2,2-bis (3,4-dicarboxyphenyl) hexafluoropropane dianhydride is desirable. Two or more of the above acid dianhydrides may be mixed and used.

Examples of aromatic diamines (ie those that form a diamine residue of Ar ₂ ) include those having one aromatic group; p-phenylenediamine, m-phenylenediamine, p-aminobenzylamine, m-amino Those having two aromatic groups such as benzylamine, diaminotoluenes, diaminoxylenes, diaminonaphthalenes, diaminoanthracenes; 4,4′-diaminobiphenyl, 3,4′-diaminobiphenyl, 3,3′- Diaminobiphenyl, o-tolidine, m-tolidine, o-dianisidine, 4,4'-diaminodiphenylmethane, 3,4'-diaminodiphenylmethane, 3,3'-diaminodiphenylmethane, 4,4'-diaminodiphenyl ether, 3,4 '-Diaminodiphenyl ether, 3,3'-diaminodiphenyl ether, 4 , 4'-diaminodiphenyl sulfone, 3,4'-diaminodiphenyl sulfone, 3,3'-diaminodiphenyl sulfone, 4,4'-diaminodiphenyl ketone, 3,4'-diaminodiphenyl ketone, 3,3'-diamino Aromatic such as diphenyl ketone, 2,2-bis (4-aminophenoxy) propane, 2,2-bis (3-aminophenoxy) propane, 2- (3-aminophenyl) -2- (4-aminophenyl) propane Having three group groups; 1,4-bis (4-aminophenoxy) benzene, 1,4-bis (3-aminophenoxy) benzene, 1,3-bis (4-aminophenoxy) benzene, 1,3 -Bis (3-aminophenoxy) benzene, 1,4-bis (4-aminobenzoyl) benzene, 1,4-bis (3-aminobenzoyl) benzene Zen, 1,3-bis (4-aminobenzoyl) benzene, 1,3-bis (3-aminobenzoyl) benzene, 9,9-bis (4-aminophenyl) fluorene, etc., having four or more aromatic groups 2,2-bis [4- (4-aminophenoxy) phenyl] propane, 4,4′-bis (4-aminophenoxy) biphenyl, 4,4′-bis (3-aminophenoxy) biphenyl, bis [ 4- (4-aminophenoxy) phenyl] sulfone, bis [4- (3-aminophenoxy) phenyl] sulfone, bis [4- (4-aminophenoxy) phenyl] ether, bis [4- (3-aminophenoxy) Phenyl] ether, 4,4′-bis (4-aminophenoxy) benzophenone, 4,4′-bis (3-aminophenoxy) benzophenone, 1,4 Bis [4- (2-, 3- or 4-aminophenoxy) benzoyl] benzene, 1,3-bis [4- (2-, 3- or 4-aminophenoxy) benzoyl] benzene, 1,4-bis [ 3- (2-, 3- or 4-aminophenoxy) benzoyl] benzene, 1,3-bis [3- (2-, 3- or 4-aminophenoxy) benzoyl] benzene, 4,4′-bis [4 -(2-, 3- or 4-aminophenoxy) benzoyl] diphenyl ether, 4,4'-bis [3- (2-, 3- or 4-aminophenoxy) benzoyl] diphenyl ether, 4,4'-bis [4 -(2-, 3- or 4-aminophenoxy) benzoyl] biphenyl, 4,4'-bis [3- (2-, 3- or 4-aminophenoxy) benzoyl] biphenyl Enyl, 4,4′-bis [4- (2-, 3- or 4-aminophenoxy) benzoyl] diphenylsulfone, 4,4′-bis [3- (2-, 3- or 4-aminophenoxy) benzoyl ] Diphenyl sulfone etc. are mentioned. In addition, it is desirable that the polyimide having the repeating unit represented by the general formula (1) is solvent-soluble. Therefore, the aromatic group may vary depending on the type of aromatic tetracarboxylic dianhydride selected. Use of a diamine containing two or more is preferred. In consideration of the solubility in addition to the solvent solubility, 4,4′-diaminodiphenyl ether, 3,4′-diaminodiphenyl ether, 1,4-bis (4-aminophenoxy) benzene, 1, 4-bis (3-aminophenoxy) benzene, 1,3-bis (4-aminophenoxy) benzene, 1,3-bis (3-aminophenoxy) benzene, 2,2-bis [4- (4-aminophenoxy) ) Phenyl] propane, 4,4′-bis (4-aminophenoxy) biphenyl, 4,4′-bis (3-aminophenoxy) biphenyl, bis [4- (4-aminophenoxy) phenyl] sulfone, bis [4 The use of-(3-aminophenoxy) phenyl] sulfone, 9,9-bis (4-aminophenyl) fluorene is preferred.

  In particular, a combination of tetracarboxylic dianhydride and diamine that is preferable from the viewpoint of solvent solubility is 4,4′-oxydiphthalic dianhydride and 2,2-bis [4- (4-aminophenoxy) phenyl] propane. And a combination of 2,2-bis (3,4-dicarboxyphenyl) hexafluoropropane dianhydride and 1,3-bis (3-aminophenoxy) benzene.

  Furthermore, the following general formula (3):

(In the formula, p is an integer mixed value of 0 to 20, R ₂ represents a methyl group, an isopropyl group, a phenyl group or a vinyl group, and R ₃ represents a divalent carbon atom having 1 to 7 carbon atoms. A siloxane diamine represented by a hydrogen group (for example, trimethylene, tetramethylene, phenylene, etc.) may be mixed as a diamine component in an amount of 1 to 50 mol%.

  The solvent used for the reaction of the polyamic acid is not particularly limited as long as it is an inert solvent. For example, N, N-dimethylformamide, N, N-dimethylacetamide, N-methyl-2-pyrrolidone, dimethyl sulfoxide, tetra Methylurea and the like can be used alone or in a mixed form. Particularly preferred are N, N-dimethylacetamide and N-methyl-2-pyrrolidone. Further, these solvents may be used by mixing benzene, toluene, xylene, mesitylene, chlorobenzene, diglyme, triglyme and the like in an arbitrary ratio. The reaction is usually carried out at a solute concentration of 5 to 80%.

  Throughout this specification and claims, “soluble” or “solvent soluble” means that 5 parts by weight or more of a solute is dissolved in 100 parts by weight of a solvent. For example, “solvent soluble polyimide” It means that 5 parts by weight or more of polyimide is dissolved in 100 parts by weight of at least one solvent selected from the solvents listed above. More preferably, at least one solvent 100 selected from N, N-dimethylformamide, N, N-dimethylacetamide, N-methyl-2-pyrrolidone, dimethyl sulfoxide, tetramethylurea and mixtures thereof at 25 ° C. It means that 5 parts by weight or more of polyimide containing the repeating unit represented by the formula (1) of the present invention is dissolved in parts by weight.

  Next, the imidization reaction is performed by dehydrating the polyamic acid obtained by the above reaction by a known method. For example, the chemical imidization method is not particularly limited to the polyamic acid solution obtained by the above reaction, but is not limited to acetic anhydride, trifluoroacetic anhydride, polyphosphoric acid, phosphorus pentoxide, phosphorus pentachloride, thionyl chloride. The dehydrating agent such as is used alone or in combination of two or more. A catalyst such as pyridine may be used. In the thermal imidization method, a solvent such as benzene, toluene, xylene, mesitylene, chlorobenzene, diglyme, and triglyme is mixed in an arbitrary ratio to the polyamic acid solution obtained by the above reaction, heated, and produced by ring closure. The water is drained while draining the water out of the system. These solvents may be used alone or in combination of two or more.

  The imidation rate in the imidization reaction from polyamic acid to polyimide is preferably 80% or more in order to avoid generation of volatile components during molding, generation of voids due to dehydration, and reaction of isoimide oligomer and amine. Is preferably 90% or more, more preferably 95% or more.

Here, the imidization ratio, infrared spectrum (IR) imide and characteristic absorption bands of amide by measuring (respectively, 1375 cm and around 1540cm around ^{-1 -1)} absorbance was calculated from the respective peak intensities detected in The following formula:
(Absorbance of imide) ÷ [(Absorbance of imide) + (Absorbance of amic acid)] × 100
The value obtained by inserting into.

  Next, the isoimide oligomer according to the present invention will be described. First, the “oligomer” in the isoimide oligomer means that i in the general formula (2) is 0-20. “Isoimide” corresponds to a positional isomer of imide, and is represented by the following general formula (4):

In the molecule, it has a structure shown in (2), and it undergoes a transition in the molecule at a temperature of 180 to 300 ° C. to become an imide.

  Next, production of the isoimide oligomer according to the present invention will be described. The following general formula (2):

(Wherein i is a number from 0 to 20, more preferably a number from 0 to 10, more preferably a number from 0 to 5, Ar ₃ is a tetracarboxylic acid residue, Ar ₄ is a diamine residue, Ar ₅ is a monoamine residue, and R ₁ is hydrogen or an organic group having 1 to 24 carbon atoms.) The production of an isoimide oligomer represented by Manufacture. The production of the amic acid oligomer is not particularly limited and may be a known method, and is usually performed in a solvent. For example, it is produced by reacting an aromatic tetracarboxylic dianhydride, an aromatic diamine, and a molecular terminal sealing material in a polar solvent. Specific examples of the tetracarboxylic dianhydride used here (that is, the one forming the tetracarboxylic acid residue of Ar ₃ ) include pyromellitic dianhydride, 3,3 ′, 4,4′-biphenyltetra Carboxylic dianhydride, 2,3 ′, 3,4′-biphenyltetracarboxylic dianhydride, 2,2 ′, 3,3′-biphenyltetracarboxylic dianhydride, 4,4′-oxydiphthalic acid Anhydride, 3,4'-oxydiphthalic dianhydride, 3,3'-oxydiphthalic dianhydride, 4,4'-benzophenone tetracarboxylic dianhydride, 4,4'-diphenylsulfone tetracarboxylic dianhydride 2,2-bis (3,4-dicarboxyphenyl) propane dianhydride, 2,2-bis (3,4-dicarboxyphenyl) hexafluoropropane dianhydride, 1,2,7,8- Naphthalene Such Rakarubon acid dianhydride. In addition, it is desirable that the isoimide oligomer represented by the general formula (2) is soluble in the solvent. Therefore, although it varies depending on the molecular weight and the kind of the aromatic diamine selected, 4,4′-oxydiphthalic dianhydride , 3,4'-oxydiphthalic dianhydride, 3,3'-oxydiphthalic dianhydride, 4,4'-benzophenone tetracarboxylic dianhydride, 4,4'-diphenylsulfone tetracarboxylic dianhydride 2,2-bis (3,4-dicarboxyphenyl) propane dianhydride and 2,2-bis (3,4-dicarboxyphenyl) hexafluoropropane dianhydride are desirable. Two or more of the above acid dianhydrides may be mixed and used.

Examples of aromatic diamines (ie, those that form a diamine residue of Ar ₄ ) have one aromatic group; p-phenylenediamine, m-phenylenediamine, p-aminobenzylamine, m- Aminobenzylamine, diaminotoluenes, diaminoxylenes, diaminonaphthalenes, diaminoanthracenes and the like having two aromatic groups; 4,4′-diaminobiphenyl, 3,4′-diaminobiphenyl, 3,3 ′ -Diaminobiphenyl, o-tolidine, m-tolidine, o-dianisidine, 4,4'-diaminodiphenylmethane, 3,4'-diaminodiphenylmethane, 3,3'-diaminodiphenylmethane, 4,4'-diaminodiphenyl ether, 3, 4′-diaminodiphenyl ether, 3,3′-diaminodiphenyl ether, 4,4′-diaminodiphenyl sulfone, 3,4′-diaminodiphenyl sulfone, 3,3′-diaminodiphenyl sulfone, 4,4′-diaminodiphenyl ketone, 3,4′-diaminodiphenyl ketone, 3,3′- Diaminodiphenyl ketone, 2,2-bis (4-aminophenoxy) propane, 2,2-bis (3-aminophenoxy) propane, 2- (3-aminophenyl) -2- (4-aminophenyl) propane, etc. Having three aromatic groups; 1,4-bis (4-aminophenoxy) benzene, 1,4-bis (3-aminophenoxy) benzene, 1,3-bis (4-aminophenoxy) benzene, 1, 3-bis (3-aminophenoxy) benzene, 1,4-bis (4-aminobenzoyl) benzene, 1,4-bis (3-aminobenzoyl) 4 or more aromatic groups such as benzene, 1,3-bis (4-aminobenzoyl) benzene, 1,3-bis (3-aminobenzoyl) benzene, 9,9-bis (4-aminophenyl) fluorene 2,2-bis [4- (4-aminophenoxy) phenyl] propane, 4,4′-bis (4-aminophenoxy) biphenyl, 4,4′-bis (3-aminophenoxy) biphenyl, bis [ 4- (4-aminophenoxy) phenyl] sulfone, bis [4- (3-aminophenoxy) phenyl] sulfone, bis [4- (4-aminophenoxy) phenyl] ether, bis [4- (3-aminophenoxy) Phenyl] ether, 4,4′-bis (4-aminophenoxy) benzophenone, 4,4′-bis (3-aminophenoxy) benzophenone, 1, -Bis [4- (2-, 3- or 4-aminophenoxy) benzoyl] benzene, 1,3-bis [4- (2-, 3- or 4-aminophenoxy) benzoyl] benzene, 1,4-bis [3- (2-, 3- or 4-aminophenoxy) benzoyl] benzene, 1,3-bis [3- (2-, 3- or 4-aminophenoxy) benzoyl] benzene, 4,4′-bis [ 4- (2-, 3- or 4-aminophenoxy) benzoyl] diphenyl ether, 4,4′-bis [3- (2-, 3- or 4-aminophenoxy) benzoyl] diphenyl ether, 4,4′-bis [ 4- (2-, 3- or 4-aminophenoxy) benzoyl] biphenyl, 4,4′-bis [3- (2-, 3- or 4-aminophenoxy) benzoyl] Phenyl, 4,4′-bis [4- (2-, 3- or 4-aminophenoxy) benzoyl] diphenylsulfone, 4,4′-bis [3- (2-, 3- or 4-aminophenoxy) benzoyl ] Diphenyl sulfone etc. are mentioned. It is desirable that the isoimide oligomer represented by the general formula (2) is soluble in a solvent, and therefore, depending on the molecular weight and the aromatic tetracarboxylic dianhydride selected, two aromatic groups are present. Use of the diamine containing above is preferable. In consideration of easy availability in addition to solvent solubility, 4,4′-diaminodiphenyl ether, 3,4′-diaminodiphenyl ether, 1,4-bis (4-aminophenoxy) benzene, 1 , 4-bis (3-aminophenoxy) benzene, 1,3-bis (4-aminophenoxy) benzene, 1,3-bis (3-aminophenoxy) benzene, 2,2-bis [4- (4-amino Phenoxy) phenyl] propane, 4,4′-bis (4-aminophenoxy) biphenyl, 4,4′-bis (3-aminophenoxy) biphenyl, bis [4- (4-aminophenoxy) phenyl] sulfone, bis [ Preference is given to using 4- (3-aminophenoxy) phenyl] sulfone, 9,9-bis (4-aminophenyl) fluorene.

  Furthermore, the following general formula (3):

(In the formula, p is an integer mixed value of 0 to 20, R ₂ represents a methyl group, an isopropyl group, a phenyl group or a vinyl group, and R ₃ represents a divalent carbon atom having 1 to 7 carbon atoms. A siloxane diamine represented by a hydrogen group (for example, trimethylene, tetramethylene, phenylene, etc.) may be mixed as a diamine component in an amount of 1 to 50 mol%.

  As an example of the molecular end sealing material, the following general formula (5):

(Wherein, Ar ₅ is a monoamine residue, and R ₁ is hydrogen or an organic group having 1 to 24 carbon atoms).

R ₁ is hydrogen and the following general formula (6):

(Wherein X is a single bond, —O—, —CO—, —COO—, —C (CH ₃ ) ₂ —, —C (CF ₃ ) ₂ —, which may be the same or different from each other. And Ar ₅ is selected from the group consisting of organic groups represented by the following general formula (7):

(Wherein X is a single bond, —O—, —CO—, —COO—, —C (CH ₃ ) ₂ —, —C (CF ₃ ) ₂ —, which may be the same or different from each other. ) Is selected from the group consisting of organic groups represented by

  The branch end-capping material represented by the general formula (5) is, specifically, in consideration of availability, specifically o-aminophenylacetylene, m-aminophenylacetylene, p-aminophenylacetylene, Examples include 2-phenylethynylaniline, 3-phenylethynylaniline, 4-phenylethynylaniline, and preferably m-aminophenylacetylene, p-aminophenylacetylene, 3-phenylethynylaniline, 4-phenylethynylaniline. . In addition, m-aminophenyl acetylene can be manufactured by the method described, for example in Unexamined-Japanese-Patent No. 10-36325 and p-aminophenyl acetylene, for example in Unexamined-Japanese-Patent No. 9-143129.

  Particularly, a combination of tetracarboxylic dianhydride, diamine and molecular end-capping material suitable for solvent solubility is 4,4′-oxydiphthalic dianhydride and 1,3-bis (3-aminophenoxy) benzene. And a combination of benzophenone tetracarboxylic dianhydride, 1,3-bis (3-aminophenoxy) benzene and m-aminophenyl acetylene.

  The solvent used in the reaction of the amic acid oligomer is not particularly limited as long as it is an inert solvent for the reaction. For example, N, N-dimethylformamide, N, N-dimethylacetamide, N-methyl-2-pyrrolidone, dimethyl sulfoxide, Tetramethylurea, tetrahydrofuran and the like can be used alone or in a mixed form. Particularly preferred are N, N-dimethylacetamide, N-methyl-2-pyrrolidone and tetrahydrofuran. Further, these solvents may be used by mixing a solvent such as benzene, toluene, xylene, mesitylene, chlorobenzene, diglyme, triglyme in an arbitrary ratio. The reaction is usually carried out at a solute concentration of 5 to 80%.

  The charged amount of the molecular end sealing material varies depending on the molecular weight of the target isoimide oligomer, but is usually 1 to several times the number of moles of the difference between the number of moles of acid anhydride and diamine, and preferably 1 .5-4 times the number of moles.

  The isoimidization reaction is performed by dehydrating the amic acid oligomer obtained by the above reaction by a known method. For example, although not particularly limited to the amic acid oligomer obtained by the above reaction, dehydration is performed by using a dehydrating agent such as trifluoroacetic anhydride or DCC alone or in combination of two or more.

  In the case of the myriad trifluoroacetic acid method, after the reaction is completed, in order to remove by-produced trifluoroacetic acid, the reaction system is poured into isopropanol to precipitate oligomer crystals, which are collected by filtration, washed and dried. Isoimide oligomers. On the other hand, in the case of the DCC method, after the reaction is completed, the reaction system is first filtered in order to remove by-produced DCU. Next, the filtrate may be poured into isopropanol or the like to take out oligomer crystals, but in the case of the present invention, it is preferable to obtain an isoimide oligomer in a solution state for mixing with polyimide. Therefore, the DCC method is adopted, and it is preferable to use the solution after removing the DCU as it is in the next step.

  In the isoimidization reaction from an amic acid oligomer to an isoimide oligomer, imidization may occur along with isoimidation. In order to avoid generation of volatile components at the time of molding and generation of voids due to dehydration, the total of the imidization rate and isoimidization rate is preferably 80% or more, 90% or more, and more preferably 95% or more. More desirable. At this time, the isoimidization rate is sufficient if the generated oligomer is soluble in the solvent, and is at least 1%, preferably 40% or more, and more preferably 60% or more.

Here, the imidization rate or isoimidization rate, infrared spectrum (IR) isoimide by measurement, characteristic absorption bands of imide and amic acid (respectively, 937Cm around ^-1, 1375 cm ^-1 and around 1540cm around ^-1 The absorbance calculated from the peak intensities detected in) is expressed by the following formula:

The value obtained by inserting into.

  Next, the manufacturing method of a polyimide resin composition is demonstrated. The polyimide resin composition containing the polyimide containing the repeating unit represented by the general formula (1) obtained by the above reaction and the isoimide oligomer represented by the general formula (2) is mixed in a predetermined weight ratio. It is obtained by doing. The mixing ratio (weight) of the polyimide containing the repeating unit represented by the general formula (1) and the isoimide oligomer represented by the general formula (2) is in the range of 5/95 to 95/5, preferably 10/90 to 90/10, more preferably 65/35 to 80/20.

  The polyimide resin composition of the present invention includes a polyimide containing a repeating unit represented by the general formula (1) in the form of powder or varnish, and an isoimide oligomer represented by the general formula (2) in the form of powder or varnish. Is obtained by mixing. That is, polyimide powder and isoimide oligomer powder, polyimide powder and isoimide oligomer varnish, polyimide varnish and isoimide oligomer varnish, polyimide varnish and isoimide oligomer varnish are mixed and obtained in powder, varnish or film form Can do.

  The varnish of the present invention can be prepared from the polyimide resin composition of the present invention. The solvent used for preparing the varnish is not particularly limited as long as it is soluble in each component, and may preferably be a reaction solvent used for preparing each component. As the solvent, for example, N, N-dimethylformamide, N, N-dimethylacetamide, N-methyl-2-pyrrolidone, dimethyl sulfoxide, tetramethylurea, tetrahydrofuran and the like can be used alone or in a mixed form. Particularly preferred are N, N-dimethylacetamide, N-methyl-2-pyrrolidone and tetrahydrofuran. Further, these solvents may be used by mixing a solvent such as benzene, toluene, xylene, mesitylene, chlorobenzene, diglyme, triglyme in an arbitrary ratio. Moreover, after completion | finish of reaction of each component, the solution obtained by performing an appropriate post-process may be mixed and a varnish may be prepared. The concentration of the polyimide resin composition of the present invention contained in the varnish is appropriately selected depending on the solubility of each component, the use mode of the varnish, and the like, without particular limitation, and is, for example, a solute concentration of 5 to 80%.

  The heat-resistant adhesive of the present invention can be prepared from the polyimide resin composition of the present invention or the varnish. The solvent used for the preparation of the heat-resistant adhesive is not particularly limited as long as it is not chemically reactive with each component and is soluble, and the solvent used for the preparation of the varnish, or lower alcohols (for example, Methanol, ethanol, propanol, isopropanol, butanol, etc.), lower alkanes (pentane, hexane, heptane, cyclohexane, etc.), ketones (acetone, methyl ethyl ketone, methyl isobutyl ketone, etc.), halogenated hydrocarbons (dichloromethane, carbon tetrachloride, Fluorobenzene, etc.), aromatic hydrocarbons (benzene, toluene, xylene, etc.), esters (methyl acetate, ethyl acetate, butyl acetate, etc.) and the like may be used alone or in a mixed form. . The concentration of the polyimide resin composition of the present invention contained in the heat-resistant adhesive is not particularly limited and is appropriately selected according to the solubility of each component, the use mode of the heat-resistant adhesive, etc., for example, 5 to 80% Preferably, the solute concentration is Further, various fillers or additives may be mixed within a range not impairing the object of the present invention.

  By applying the polyimide resin composition of the present invention, usually a varnish containing the polyimide resin composition of the present invention to a substrate such as glass, aluminum, copper, stainless steel, PET film, polyimide film, and drying the solvent. The film can be obtained as a film having a desired thickness, preferably 1 μm to 200 μm, more preferably 1 to 100 μm. The obtained film is appropriately subjected to a curing treatment at 180 to 450 ° C. to obtain a cured product.

  A varnish containing the polyimide resin composition of the present invention can be directly applied to a heat-resistant film such as Kapton, or a metal such as copper, stainless steel or aluminum and dried to obtain a laminated film or a metal laminate. Alternatively, a film obtained from the polyimide resin composition of the present invention is laminated on at least one surface of a heat-resistant film such as Kapton, or a metal foil such as copper, stainless steel, or aluminum, and is thermocompression-bonded to form a laminated film or a metal laminated film You may get a body. The obtained laminated film or metal laminate is appropriately subjected to a curing treatment at 180 to 450 ° C. to obtain a cured product of the laminated film or metal laminate.

  Furthermore, the varnish containing the polyimide resin composition of the present invention is impregnated into carbon fiber, glass fiber, aramid fiber, polyarylate fiber (fully aromatic polyester fiber) or boron fiber, or a woven or non-woven fabric using them. To form a prepreg. The obtained prepreg is appropriately subjected to a curing treatment at 180 to 450 ° C. to obtain a cured product.

  The laminated film, metal laminate or prepreg thus obtained or a cured product thereof can be used not only in the electric and electronic fields but also in automobiles, aerospace industry, building materials and the like.

  In the production of a multilayer printed wiring board using the polyimide resin composition of the present invention, first, a copper foil with bumps and the film of the present invention are laminated and pressed under desired pressure and temperature conditions. The polyimide resin composition of this invention has a glass transition temperature lower than the polyimide which is not mixing the isoimide oligomer component, and the glass transition temperature before hardening is 200 degrees C or less suitably. That is, in the temperature range from the glass transition temperature to the curing start temperature, the fluidity of the resin composition is high, so by pressing in that temperature range, the punch-through property of the bump and the resin composition fillability at the base of the bump Therefore, the interlaminar adhesion and electrical properties of the multilayer printed wiring board are not impaired.

  Next, a curing process is performed at 180 to 450 ° C., the insulating layer is cured, and circuit processing is performed. By performing the curing treatment, the molecular terminal triple bond of the isoimide oligomer forms a crosslinked structure, so that the glass transition temperature after thermosetting is high, and preferably the glass transition temperature after thermosetting is 201 ° C. or higher. In addition, the glass transition temperature is 40 ° C. or higher, preferably 60 ° C. or higher, more preferably 80 ° C. or higher, compared to the glass transition temperature before curing. For this reason, the cured resin composition has excellent mechanical properties, electrical properties, heat resistance, and solvent resistance.

  Furthermore, in order to laminate successive conductor layers and insulating layers and perform bump penetration, filling resin composition at the base of bumps, bonding, etc., press again in the temperature range from the glass transition temperature to the curing start temperature. At this time, since the insulating layer of the lower wiring board is already cured, the glass transition temperature is higher than the glass transition temperature of the insulating layer of the upper wiring board as described in the above paragraph. The temperature is 40 ° C or higher, preferably 60 ° C or higher, more preferably 80 ° C or higher. Therefore, the insulating layer of the lower wiring board does not deform in that temperature region. For this reason, by using the resin composition of the present invention, a product having excellent reliability such as electrical characteristics in the production of a multilayer printed wiring board in which processes such as lamination, hot pressing, curing, and circuit processing are repeated is provided. It became possible.

  The ratio (α1 / α2) of the thermal expansion coefficient before and after curing of the polyimide resin composition of the present invention is 3 or more, and exhibits excellent heat resistance in a high temperature region. Here, α1 is a coefficient of thermal expansion in the temperature range from the glass transition temperature of the polyimide resin composition of the present invention before curing to the glass transition temperature + 50 ° C., and α2 is the polyimide resin composition of the present invention after curing. It is a thermal expansion coefficient in a temperature range from the glass transition temperature to the glass transition temperature + 50 ° C.

  In order to clarify aspects of the present invention, examples and comparative examples are shown below, but the present invention is not limited to only the examples shown here.

Example 1
Synthesis of polyimide: 4,4′-oxydiphthalic dianhydride 24.8172 g (0.08 mol), 2,2-bis [4- (4-aminophenoxy) phenyl] propane 32.8406 g (0 .08 mol), 327.4 g of N-methyl-2-pyrrolidone (NMP) and 33.0 g of xylene were charged, and the mixture was stirred in a nitrogen stream at room temperature for 2 hours to synthesize polyamic acid. Subsequently, the flask was heated to 200 ° C. and refluxed for 8 hours while allowing water from imidization to flow out of the system together with xylene. Cooling was performed to obtain a polyimide solution having a solute concentration of 15% and a viscosity (B-type viscometer: manufactured by Tokyo Keiki Co., Ltd.) of 80000 mPa · s.

  Synthesis of isoimide oligomer: 44.8172 g (0.08 mol) of 4,4′-oxydiphthalic dianhydride, 14.7371 (0.04 mol) of 4,4′-bis (4-aminophenoxy) biphenyl in a four-necked flask ), M-aminophenylacetylene 9.3717 g (0.08 mol) and NMP 215.9 g were charged and stirred at room temperature for 3 hours in a nitrogen stream. While cooling the flask to 5 ° C., a solution obtained by dissolving 33.0 g (0.16 mol) of DCC in 61.3 g of NMP was added dropwise from a dropping funnel over 1 hour. Then, after returning to room temperature and stirring for 2 hours, DCU produced as a by-product in the reaction was filtered off to obtain an isoimide oligomer solution having a solute concentration of 15%.

  Sample A; 20:80, Sample B; 70:30, Sample C; 60:40, Sample D; 50:50, Sample by weight ratio of solutes of polyimide and isoimide oligomer obtained as described above E: 40:60 was mixed and stirred for 3 hours. The film was cast on a glass plate and dried at 70 to 220 ° C. to obtain a film having a thickness of 25 μm. Next, the obtained film was subjected to heat treatment (300 ° C., 30 minutes) to be cured.

From the obtained film before and after the heat treatment, a test piece of 5 × 17 mm was prepared, and the glass transition temperature and the thermal expansion coefficient were measured as follows:
Glass transition temperature: Using a thermomechanical analysis (TMA) device (manufactured by Shimadzu Corporation, TMA-60), the rate of temperature increase was 5 ° C./min in a constant load mode with a distance of 15 mm between chucks and a load of 4 g. When the temperature was raised from 40 to 400 ° C., the glass transition temperature was calculated from the TMA extrapolation point by using the analysis software.
Thermal expansion coefficient: The thermal expansion coefficient was calculated based on the slope of the TMA curve in the temperature range from the glass transition temperature determined as described above to a temperature higher by 50 ° C. than the glass transition temperature.

  Table 1 shows the glass transition temperature of each test piece obtained.

Example 2 (Adhesion test)
The film before heat treatment (polyimide / oligomer mixing ratio 50/50) obtained in Example 1 was sandwiched between electrolytic copper foils (18 μm thick) and thermocompression bonded at 250 ° C. and 5 MPa for 30 minutes. The 90 ° peel adhesion strength to the copper foil was measured according to IPC-TM-650 method 2.4.9 and found to be 0.8 kN / m. Furthermore, thermocompression bonding was performed at 300 ° C. and 5 MPa for 30 minutes. The 90 ° peel adhesion strength to the copper foil was 1.0 kN / m.

Example 3 (Solder heat resistance test)
A film sample sandwiched between the electrolytic copper foils obtained in Example 2 and thermocompression bonded at 300 ° C. and 5 MPa for 30 minutes was cut into about 2 cm square and immersed in a solder bath at 290 ° C. for 10 seconds. I couldn't see it.

Example 4 (Solvent resistance test)
The film samples obtained before and after the heat treatment obtained in Example 1 were immersed in NMP, chloroform, and THF solvents at 25 ° C. for 24 hours, and the solvent resistance was visually observed. The film before the heat treatment was dissolved in various solvents, whereas the film after the heat treatment was not completely dissolved in the solvent.

Example 5
In the same manner as in Example 1, various components were changed to prepare a polyimide resin composition. The composition and results are shown in Table 2. However, the mixing ratio of polyimide and isoimide oligomer is 50/50.

The abbreviations in the table indicate the following.
4-ODPA: 4,4′-oxydiphthalic dianhydride BAPP: 2,2-bis [4- (4-aminophenoxy) phenyl] propane APB: 1,3-bis (3-aminophenoxy) benzene m-APA : M-aminophenoxyacetylene BTDA: benzophenone tetracarboxylic dianhydride.

Comparative Example 1
The polyimide solution obtained in Example 1 was cast on a glass plate and dried at 70 to 220 ° C. to obtain a film containing no oligomer component with a thickness of 25 μm. When thermal analysis was performed, there was almost no change in the glass transition temperature before and after the heat treatment. Further, an adhesion test was performed in the same manner as in Example 2, but the adhesive strength was only 0.2 kN / m. Further, when the solder heat resistance test was performed in the same manner as in Example 3, blistering was observed, and even the heat-treated film showed solubility in NMP.

Comparative Example 2
In the synthesis of the isoimide oligomer, an isoimide having no triple bond at the end of 25 μm in thickness was used in the same manner as in Example 5 except that 7.4501 g (0.08 mol) of aniline was used instead of m-aminophenylacetylene. A film having an oligomer content of 50% was prepared. As a result of thermal analysis, the polyimide solution obtained before and after the heat treatment was cast on a glass plate and dried at 70 to 220 ° C. to obtain a film containing no oligomer component having a thickness of 25 μm. When thermal analysis was performed, there was almost no change in the glass transition temperature before and after the heat treatment. Further, an adhesion test was performed in the same manner as in Example 2, but the adhesion strength was only 0.3 kN / m. Further, when the solder heat resistance test was performed in the same manner as in Example 3, blistering was observed, and even the heat-treated film showed solubility in NMP.

  The polyimide resin composition of the present invention is excellent in meltability and fluidity at relatively low temperatures, and has good workability at low temperatures. Further, a cured product obtained by crosslinking and curing by heat treatment is excellent in adhesiveness, solder heat resistance, and electrical properties, and is particularly suitable as an interlayer insulating material for multilayer printed wiring boards.

Claims (14)

The following general formula (1) obtained by reacting a tetracarboxylic dianhydride component A and a diamine component B in a range of 0.95 ≦ A / B <1.10:

(Wherein n is a number of 21 or more, Ar ₁ is a tetracarboxylic acid residue, and Ar ₂ is a diamine residue), and a polyimide containing a repeating unit represented by the following general formula (2):

(In the formula, i is a number of 0 to 20, Ar ₃ is a tetracarboxylic acid residue, Ar ₄ is a diamine residue, Ar ₅ is a monoamine residue, R ₁ is hydrogen or 1 to 1 carbon atoms. The polyimide resin composition is characterized in that it contains an isoimide oligomer represented by a weight ratio of 5/95 to 95/5.   The polyimide resin composition of Claim 1 which contains a polyimide and an isoimide oligomer by the weight ratio of 65/35-20/80.   The polyimide resin composition of Claim 1 or 2 whose polyimide containing the repeating unit represented by General formula (1) is a solvent soluble polyimide.   The polyimide resin composition according to any one of claims 1 to 3, wherein a difference in glass transition temperature between before and after curing of the polyimide resin composition is 40 ° C or more.   The varnish containing the polyimide resin composition of any one of Claims 1-4.   A heat-resistant adhesive comprising the polyimide resin composition according to claim 1.   The film obtained by apply | coating the varnish of Claim 5 to a base material, and drying.   A laminated film obtained by laminating the polyimide resin composition according to any one of claims 1 to 4 on at least one side of a heat resistant film.   A cured product obtained by thermally curing the laminated film according to claim 8.   The metal laminated body formed by laminating | stacking the polyimide resin composition of any one of Claims 1-4 on the at least single side | surface of metal foil.   A metal laminate cured product obtained by thermosetting the metal laminate according to claim 10.   A prepreg obtained by impregnating the varnish according to claim 5 into carbon fiber, glass fiber, aramid fiber, polyarylate fiber, boron fiber, or a woven or non-woven fabric using the same.   A cured product obtained by thermally curing the prepreg according to claim 12.   The multilayer printed wiring board formed using the polyimide resin composition of any one of Claims 1-13, a heat resistant adhesive, a varnish, a film, a laminated film, a metal laminated body, a prepreg, or those hardened | cured materials.