JP5100894B2 - Polyimide resin, production method thereof, adhesive resin composition, coverlay film, and circuit board - Google Patents

Description

  The present invention relates to a polyimide resin useful as an adhesive in a circuit board such as a flexible printed wiring board, a production method thereof, and use thereof.

  In recent years, with the progress of downsizing, weight reduction, and space saving of electronic devices, flexible printed wiring boards (FPCs) that are thin, light, flexible, and have excellent durability even after repeated bending are used. The demand for Circuits) is increasing. FPC can be mounted three-dimensionally and densely in a limited space. For example, it can be used for wiring of movable parts of electronic devices such as HDDs, DVDs, mobile phones, and parts such as cables and connectors. It is expanding.

  For the FPC, a coverlay film is used for the purpose of protecting the wiring portion. The coverlay film is formed by laminating a coverlay film material made of a synthetic resin such as a polyimide resin and an adhesive layer. In manufacturing an FPC, a coverlay film material is attached to a circuit board through an adhesive layer by using a method such as hot pressing. The adhesive layer is required to have high adhesion to both the circuit wiring pattern such as copper wiring and the film material for coverlay. As an adhesive for such a coverlay film, it can be processed under relatively low temperature thermocompression bonding conditions, and it has excellent heat resistance and other characteristics, and it can be used as a mixed resin of polyimide resin and epoxy resin having a siloxane unit. In addition, an adhesive resin composition for printed circuit boards, in which one or more plasticizers selected from phosphoric acid ester-based, phthalic acid ester-based, polyester-based and fatty acid ester-based materials are blended has been proposed (for example, Patent Document 1). ).

  On the other hand, bis (3,4-dicarboxyphenyl) ether dianhydride and a specific structure are used for the purpose of improving the low temperature sticking property, low hygroscopicity, adhesive force during heating, and PCT resistance of polyimide resin used for an adhesive film. A method for producing a polyimide resin in which another acid anhydride and / or another diamine is reacted after reacting with another siloxane diamine has been proposed (for example, Patent Document 2). In addition, in order to safely and stably produce a high molecular weight polyimide resin having a silicone structure in the main chain, silicone-based diamine and silicone-based acid dianhydride are mixed in a specific molar ratio range, and heat dehydration condensation is performed. There is also proposed a method for producing a polyimide resin in which an aromatic diamine is added to a reaction solution at a predetermined molar ratio and reacted to cause a molecular weight to be controlled after the reaction is continued until no increase occurs (for example, Patent Document 3).

Japanese Unexamined Patent Publication No. 10-212468 Japanese Unexamined Patent Publication No. 2006-117945 Japanese Unexamined Patent Publication No. 2004-359874

  Since processing of FPC includes a soldering process almost indispensable, the adhesive used for the coverlay film is required to have high solder heat resistance. In this regard, polyimide resin with relatively excellent heat resistance is a material suitable as an adhesive for the coverlay film, but if the solder heat resistance can be further improved, the function as an adhesive for the coverlay film will be improved. Can be increased.

  In addition, in-vehicle electronic devices for automobiles using FPC are repeatedly placed in a high temperature environment of about 150 ° C., the adhesive strength between the FPC coverlay film and the wiring is lowered over a long period of use, and the wiring protection function is provided. There has been a problem of a significant drop. With the expansion of FPC applications, it is expected that the number of scenes where FPC is used not only in in-vehicle electronic devices but also in severe temperature environments will continue to increase. For this reason, in an FPC used in a high temperature environment, it is strongly required to take measures against a decrease in the adhesive strength of the coverlay film.

  Accordingly, an object of the present invention is to provide a polyimide resin that has excellent solder heat resistance and can form an adhesive layer that does not lower the adhesive force between the wiring layer and the coverlay film even in a use environment that is repeatedly exposed to high temperatures. Is to provide.

  As a result of intensive studies to solve the above problems, the inventors of the present invention remarkably improved the solder heat resistance of the polyimide resin when an amino compound having a primary amino group is reacted with the polyimide resin after imidization. In addition, the present inventors have found that the decrease in adhesive strength is greatly improved even when used in a high temperature environment, and completed the present invention.

  That is, the polyimide resin of the present invention is an amino compound having at least two primary amino groups as functional groups on a ketone group in polyimidesiloxane having structural units represented by the following general formulas (1) and (2). Since the amino group in the reaction reacts to form a C═N bond, the polyimidesiloxane has a structure crosslinked with the amino compound.

［式中、Ａｒは芳香族テトラカルボン酸無水物から誘導される４価の芳香族基、Ｒ_１はジアミノシロキサンから誘導される２価のジアミノシロキサン残基、Ｒ_２は芳香族ジアミンから誘導される２価の芳香族ジアミン残基をそれぞれ表し、Ａｒ及び／又はＲ_２中にはケトン基を含み、ｍ、ｎは各構成単位の存在モル比を示し、ｍは０．７５〜１．０の範囲内、ｎは０〜０．２５の範囲内である］

[Wherein Ar is a tetravalent aromatic group derived from an aromatic tetracarboxylic acid anhydride, R ₁ is a divalent diaminosiloxane residue derived from diaminosiloxane, and R ₂ is derived from an aromatic diamine. Each represents a divalent aromatic diamine residue, Ar and / or R ₂ contains a ketone group, m and n represent the molar ratio of each constituent unit, and m is from 0.75 to 1.0. N is in the range of 0 to 0.25]

The adhesive resin composition of the present invention comprises the following components (A) and (B),
(A) a polyimidesiloxane having a structural unit represented by the following general formulas (1) and (2) and having a weight average molecular weight of 10,000 to 200,000,
And (B) an amino compound having at least two primary amino groups as functional groups,
And the component (B) is contained so that the total amount of the primary amino group is within the range of 0.004 mol to 1.5 mol with respect to 1 mol of the ketone group in the component (A). .

［式中、Ａｒは芳香族テトラカルボン酸無水物から誘導される４価の芳香族基、Ｒ_１はジアミノシロキサンから誘導される２価のジアミノシロキサン残基、Ｒ_２は芳香族ジアミンから誘導される２価の芳香族ジアミン残基をそれぞれ表し、Ａｒ及び／又はＲ_２中にはケトン基を含み、ｍ、ｎは各構成単位の存在モル比を示し、ｍは０．７５〜１．０の範囲内、ｎは０〜０．２５の範囲内である］

[Wherein Ar is a tetravalent aromatic group derived from an aromatic tetracarboxylic acid anhydride, R ₁ is a divalent diaminosiloxane residue derived from diaminosiloxane, and R ₂ is derived from an aromatic diamine. Each represents a divalent aromatic diamine residue, Ar and / or R ₂ contains a ketone group, m and n represent the molar ratio of each constituent unit, and m is from 0.75 to 1.0. N is in the range of 0 to 0.25]

  The cured product of the present invention is obtained by curing the above adhesive resin composition.

The coverlay film of the present invention is a coverlay film in which an adhesive layer and a film material layer for coverlay are laminated,
The adhesive layer is formed using the adhesive resin composition.

  The circuit board of the present invention includes a base material, a wiring layer formed on the base material, and the coverlay film that covers the wiring layer. In this case, the peel strength between the wiring layer and the coverlay film after a long-term heat resistance test at 150 ° C. for 1000 hours in the air is preferably 0.2 kN / m or more.

The method for producing a polyimide resin of the present invention comprises a step of preparing a polyimide solution containing a polyimide siloxane having a ketone group,
Adding an amino compound having at least two primary amino groups as functional groups to the polyimide solution;
A step of causing a condensation reaction between the ketone group of the polyimidesiloxane and the primary amino group of the amino compound;
It has. In this case, it is preferable to add the amino compound so that the total amount of the primary amino group is within a range of 0.004 mol to 1.5 mol with respect to 1 mol of the ketone group. The method further comprises a step of reacting an acid anhydride component containing an aromatic tetracarboxylic dianhydride with a diamine component containing a diaminosiloxane and an aromatic diamine to form the polyimide siloxane. It is preferable that at least one of the aromatic tetracarboxylic dianhydride and the diamine component contains a ketone group.

A method for producing a circuit board according to the present invention is a method for producing a circuit board comprising a base material, a wiring layer formed on the base material, and a coverlay film covering the wiring layer,
A step of preparing a coverlay film having an adhesive layer by applying and drying the adhesive resin composition on the film material layer for coverlay in a solution state;
Arranging the cover lay film so that the adhesive layer contacts the wiring layer, and thermocompression bonding,
Simultaneously with the thermocompression bonding, the ketone group of the component (A) and the primary amino group of the component (B) are subjected to a condensation reaction to form a C═N bond.

  In each aspect of the present invention, the amino compound is preferably a dihydrazide compound.

The polyimide resin of the present invention has at least two primary amino groups on the ketone group contained in Ar and / or R _{2 of the} polyimidesiloxane having the structural units represented by the general formulas (1) and (2). Because it has a cross-linked structure obtained by reacting an amino compound having a functional group, it has excellent solder heat resistance and forms an adhesive layer that does not reduce the adhesion to the metal wiring layer even when it is repeatedly placed in a high temperature environment can do. Therefore, the peel strength of the coverlay film in which the adhesive layer is formed using the polyimide resin of the present invention can be increased, and the reliability of the circuit board using the coverlay film can be improved.

[Polyimide resin]
The polyimide resin of the present invention has at least two primary amino groups in the group Ar and / or the ketone group in the group R ₂ in the polyimide siloxane having the structural units represented by the general formulas (1) and (2). By reacting an amino compound having a group as a functional group to form a C═N bond, the polyimide siloxane has a structure crosslinked with an amino compound.

The group Ar in the general formulas (1) and (2) is a tetravalent aromatic group derived from an aromatic tetracarboxylic anhydride, and the group R ₁ is a divalent diaminosiloxane derived from a diaminosiloxane. And the group R ₂ is a divalent aromatic diamine residue derived from an aromatic diamine. The abundance of the structural unit represented by the formula (1) in the resin is in the range of 75 mol% to 100 mol%, preferably in the range of 80 mol% to 100 mol%.

[Polyimide siloxane]
The general formula (1), in the polyimide siloxanes having a structural unit represented by (2), during the group Ar and / or groups R _2, include a ketone group, the ketone group is, for reaction with the amino compound Involved.

  In the structural units represented by the general formulas (1) and (2), examples of the aromatic tetracarboxylic acid for forming the group Ar containing a ketone group include 3,3 represented by the following formula (3): Mention may be made of ', 4,4'-benzophenonetetracarboxylic dianhydride (BTDA).

  In addition, in the structural units represented by the general formulas (1) and (2), examples of the aromatic tetracarboxylic acid used as a raw material for forming the group Ar include, in addition to those having the ketone group, for example, 3, 3 ', 4,4'-biphenyltetracarboxylic dianhydride (BPDA), 3,3', 4,4'-diphenylsulfone tetracarboxylic dianhydride (DSDA), pyromellitic dianhydride (PMDA) Etc. can be used. These can be used alone or in combination of two or more.

In addition, examples of the group R ₁ in the structural unit represented by the general formula (1) include a diaminosiloxane residue derived from a diaminosiloxane represented by the following formula (4).

［ここで、Ｒ_３及びＲ_４は、それぞれ、酸素原子を含有していてもよい２価の有機基を示し、Ｒ_５〜Ｒ_８は、それぞれ炭素数１〜６の炭化水素基を示し、平均繰り返し数であるｍ_１は、１〜２０である］

[Wherein R ₃ and R ₄ each represent a divalent organic group that may contain an oxygen atom, R _{5 to} R ₈ each represent a hydrocarbon group having 1 to 6 carbon atoms, M ₁ that is the average number of repetitions is ₁ to 20]

In particular, as the group R ₁ , R ₃ and R ₄ in the formula (4) are each a divalent hydrocarbon group, and R _{5 to} R ₈ are each 1 to 1 carbon atoms in order to impart solubility of the polyimide. 6 having a mean repeating number of m ₁ of 5 to 15 is preferable.

  The above-mentioned diaminosiloxane residue is a group having a siloxane bond (Si-O-Si) obtained by removing an amino group from diaminosiloxane. By increasing the ratio of this siloxane bond, a plasticizer can be added. Sufficient flexibility is imparted to the adhesive layer, and warping of the coverlay film can be suppressed. Moreover, since many plastic groups are contained in the plasticizer, as an advantage of not containing the plasticizer, an adhesive using polyimidesiloxane having the structural units represented by the general formulas (1) and (2) It is mentioned that the amount of polar groups contained in the resin composition can be suppressed. For this reason, in this invention, the value of m in Formula (1) shall be 0.75 or more, Preferably it is 0.80 or more. If the value of m is less than 0.75, the effect of suppressing warpage cannot be obtained sufficiently. In addition, it is considered that increasing the siloxane bond also has an effect of reducing curing shrinkage due to a decrease in the imide bond site of polyimidesiloxane. Therefore, the value of n in the formula (2) is set to 0 to 0.25, preferably 0 to 0.2.

Thus, by introducing the siloxane skeleton into the polyimide using the diaminosiloxane represented by the above general formula (4), the resulting polyimidesiloxane is given fluidity at the time of thermocompression bonding, and on the printed circuit wiring. Fillability can be improved. As specific examples of the diaminosiloxane represented by the general formula (4), diaminosiloxanes represented by the following formulas (5) to (9) are preferable. Among these, the formula (5) or (6) is preferable. Aliphatic diaminosiloxanes are more preferred. These diaminosiloxanes can be blended in combination of two or more. Moreover, when mix | blending in combination of 2 or more types of diaminosiloxane, 90 weight part or more of aliphatic diaminosiloxane represented by Formula (5) or (6) may be mix | blended with respect to 100 weight part of all diaminosiloxanes. preferable. In the equation (4) to Formula (9), _{m 1} is an average repeating number is in the range of 1 to 20, preferably in the range of 5-15. When m ₁ is smaller than _1, the filling property when the adhesive is used is lowered, and when it exceeds 20, the adhesive property is lowered.

In the structural unit represented by the general formula (2), examples of the group R ₂ containing a ketone group (a divalent aromatic diamine residue derived from an aromatic diamine) include the following formulas (10) and (11 ) Can be mentioned. These can be used alone or in combination of two or more.

［ここで、Ｒ_９は独立に炭素数１〜６の１価の炭化水素基又はアルコキシ基を示し、ＸはＣＯを示し、ｎ_１は独立に０〜４の整数を示す］

[Wherein R ₉ independently represents a monovalent hydrocarbon group or alkoxy group having 1 to 6 carbon atoms, X represents CO, and n ₁ independently represents an integer of 0 to 4]

Examples of the aromatic diamine for forming the group R ₂ represented by the above formulas (10) and (11) include 4,4′-bis (3-aminophenoxy) benzophenone (BABP), 1,3- Bis [4- (3-aminophenoxy) benzoyl] benzene (BABB) and the like can be mentioned.

Further, in the structural unit represented by the general formula (2), as another aromatic diamine which is a raw material for forming the group R ₂ , for example, 2,2-bis (4-aminophenoxyphenyl) propane ( BAPP), 2,2′-divinyl-4,4′-diaminobiphenyl (VAB), 2,2′-dimethyl-4,4′-diaminobiphenyl (m-TB), 2,2′-diethyl-4, 4′-diaminobiphenyl, 2,2 ′, 6,6′-tetramethyl-4,4′-diaminobiphenyl, 2,2′-diphenyl-4,4′-diaminobiphenyl, 9,9-bis (4- And aminophenyl) fluorene. These aromatic diamines can be used alone or in combination of two or more.

  As for the above-mentioned acid anhydride and diamine, which are the raw materials for polyimide siloxane, only one kind thereof may be used or two or more kinds may be used in combination. In addition, acid anhydrides and diamines other than those described above can be used in combination.

  In order to improve long-term heat resistance when a polyimide resin is used as an adhesive, it is preferable to use an aromatic tetracarboxylic acid anhydride and an aromatic diamine as raw materials having few polar groups. Therefore, as the aromatic tetracarboxylic acid anhydride and aromatic diamine, the p value, which is an index representing the amount of polar groups contained in the molecule, calculated based on the following formulas (i) and (ii) It is preferable to use one that is 1.0 or less. In particular, the p value of the aromatic diamine is more preferably 0.7 or less, and further preferably 0.6 or less.

P value of aromatic tetracarboxylic anhydride = (A1 / B1) × 100 (i)
P value of aromatic diamine = (A2 / B2) × 100 (ii)
[Where A1 = (number of polar groups in group Ar) × (number of moles of group Ar)]
A2 = (number of polar groups in the radical _{R 2)} × (the number of moles of group _{R 2)}
B1 = (molecular weight of group Ar) × (number of moles of group Ar)
B2 = (molecular weight of group R ₂ ) × (number of moles of group R ₂ )]

The polar group serving as a reference for calculating the p value is classified into three stages based on the magnitude of the electric dipole moment. The first category is -X (where X is a halogen atom), -OH, -SH, -O-, -S-, -SO-, -NH-, -CO-, -CN, -P = O and -PO-, each of which is calculated as one polar group. The second category is —SO ₂ — and —CONH—, each of which is calculated as two polar groups. The third segment is —SO ₃ H, which is calculated as 3 polar groups.

[Synthesis of polyimide siloxane]
The polyimidesiloxane having the structural units represented by the general formulas (1) and (2) is obtained by reacting the aromatic tetracarboxylic acid anhydride, diaminosiloxane and aromatic diamine (if necessary) in a solvent, and a precursor resin. It can be produced by producing a polyamic acid which is For example, it is a polyimide precursor by dissolving an acid anhydride component and a diamine component in an approximately equimolar amount in an organic solvent and stirring and polymerizing at a temperature in the range of 0 to 100 ° C. for 30 minutes to 24 hours. A polyamic acid is obtained. In the reaction, the reaction components are dissolved so that the precursor to be produced is in the range of 5 to 30% by weight, preferably in the range of 10 to 20% by weight in the organic solvent. Examples of the organic solvent used for the polymerization reaction include N, N-dimethylformamide, N, N-dimethylacetamide (DMAC), N-methyl-2-pyrrolidone, 2-butanone, dimethyl sulfoxide, dimethyl sulfate, cyclohexanone, and dioxane. , Tetrahydrofuran, diglyme, triglyme and the like. Two or more of these solvents can be used in combination, and further, aromatic hydrocarbons such as xylene and toluene can be used in combination.

  The synthesized precursor is usually advantageously used as a reaction solvent solution, but can be concentrated, diluted, or replaced with another organic solvent if necessary. Moreover, since a precursor is generally excellent in solvent solubility, it is advantageously used. The method for imidizing the precursor is not particularly limited, and for example, heat treatment in which heating is performed in the solvent at a temperature within the range of 80 to 300 ° C. for 1 to 24 hours is suitably employed.

  When preparing the polyimidesiloxane having the structural units represented by the general formulas (1) and (2), the blending ratio of the acid anhydride component and the diamine component as raw materials is not particularly limited. From the standpoint that the terminal substituent of polyimide siloxane is an amino group, that is, the acid anhydride group is sealed with diamine and the polarity of the polyimide resin is suppressed, the acid anhydride component: diamine component has a molar ratio of 1. 000: 1.001 to 1.0: 1.2 is preferable.

Moreover, the polyimidesiloxane which has a structural unit represented by the said Formula (1) and (2) becomes an imide structure obtained by reaction with aromatic tetracarboxylic anhydride, diaminosiloxane, and aromatic diamine, For example, when used as an adhesive for a cover lay film, a completely imidized structure is most preferable in order to suppress copper diffusion. However, a part of the polyimide may be amic acid, and in this case, the unreacted amic acid site (—CONH— and —COOH) is regarded as a polar group that induces copper diffusion. That is, one amic acid is calculated as a substituent having four polar groups (two of -CONH- and two of -COOH). For this reason, it is preferable to complete imidization so that the P value described later is preferably 0.7 or less (more preferably 0.6 or less). The imidation ratio was measured at about 1015 cm ⁻¹ by measuring the infrared absorption spectrum of the polyimide thin film by a single reflection ATR method using a Fourier transform infrared spectrophotometer (commercial product: FT / IR620 manufactured by JASCO Corporation). Based on the absorbance of C═O stretching derived from an imide group of 1780 cm ⁻¹ , based on the benzene ring absorber.

[Amino compound]
In the polyimide resin of the present invention, amino having at least two primary amino groups as functional groups on the other side to be reacted with the ketone group of the polyimidesiloxane having the structural units represented by the above formulas (1) and (2) Examples of the compound include (I) aromatic diamine, (II) diaminosiloxane, (III) aliphatic amine, and (IV) dihydrazide compound.

(I) Aromatic diamine:
Examples of the aromatic diamine include those represented by the following formulas (12) and (13).

［ここで、Ｒ_１０は独立に炭素数１〜６の１価の炭化水素基又はアルコキシ基を示し、Ｚは単結合又は炭素数１〜１５の２価の炭化水素基、Ｏ、Ｓ、ＣＯ、ＳＯ、ＳＯ_２、ＮＨ若しくはＣＯＮＨから選ばれる２価の基を示し、ｎ_２は独立に０〜４の整数を示す］

[Wherein R ₁₀ independently represents a monovalent hydrocarbon group or alkoxy group having 1 to 6 carbon atoms, and Z represents a single bond or a divalent hydrocarbon group having 1 to 15 carbon atoms, O, S, CO , SO, SO ₂ , NH or CONH represents a divalent group, and n ₂ independently represents an integer of 0 to 4]

  Examples of such aromatic diamines include 4,4′-diaminodiphenyl ether, 2′-methoxy-4,4′-diaminobenzanilide, 1,4-bis (4-aminophenoxy) benzene, 1,3- Bis (4-aminophenoxy) benzene, 2,2′-bis [4- (4-aminophenoxy) phenyl] propane, 2,2′-dimethyl-4,4′-diaminobiphenyl, 3,3′-dihydroxy- Preferred examples include 4,4′-diaminobiphenyl, 4,4′-diaminobenzanilide, bisaniline fluorene and the like.

  Further, other examples of the aromatic diamine include 2,2-bis- [4- (3-aminophenoxy) phenyl] propane, bis [4- (4-aminophenoxy) phenyl] sulfone, bis [4- (3 -Aminophenoxy) phenyl] sulfone, bis [4- (4-aminophenoxy)] biphenyl, bis [4- (3-aminophenoxy) biphenyl, bis [1- (4-aminophenoxy)] biphenyl, bis [1- (3-Aminophenoxy)] biphenyl, bis [4- (4-aminophenoxy) phenyl] methane, bis [4- (3-aminophenoxy) phenyl] methane, bis [4- (4-aminophenoxy) phenyl] ether Bis [4- (3-aminophenoxy) phenyl] ether, bis [4- (4-aminophenoxy)] benzophenone, bis 4- (3-aminophenoxy)] benzophenone, bis [4,4 ′-(4-aminophenoxy)] benzanilide, bis [4,4 ′-(3-aminophenoxy)] benzanilide, 9,9-bis [4 -(4-aminophenoxy) phenyl] fluorene, 9,9-bis [4- (3-aminophenoxy) phenyl] fluorene, 2,2-bis- [4- (4-aminophenoxy) phenyl] hexafluoropropane, 2,2-bis- [4- (3-aminophenoxy) phenyl] hexafluoropropane, 4,4′-methylenedi-o-toluidine, 4,4′-methylenedi-2,6-xylidine, 4,4′- Methylene-2,6-diethylaniline, 4,4′-diaminodiphenylpropane, 3,3′-diaminodiphenylpropane, 4,4′-diamino Diphenylethane, 3,3′-diaminodiphenylethane, 4,4′-diaminodiphenylmethane, 3,3′-diaminodiphenylmethane, 4,4′-diaminodiphenyl sulfide, 3,3′-diaminodiphenyl sulfide, 4,4 ′ -Diaminodiphenyl sulfone, 3,3'-diaminodiphenyl sulfone, 4,4'-diaminodiphenyl ether, 3,3-diaminodiphenyl ether, 3,4'-diaminodiphenyl ether, benzidine, 3,3'-diaminobiphenyl, 3,3 '-Dimethyl-4,4'-diaminobiphenyl, 3,3'-dimethoxybenzidine, 4,4' '-diamino-p-terphenyl, 3,3' '-diamino-p-terphenyl, m-phenylenediamine , P-phenylenediamine, 2,6-diaminopyridy 1,4-bis (4-aminophenoxy) benzene, 1,3-bis (4-aminophenoxy) benzene, 4,4 ′-[1,4-phenylenebis (1-methylethylidene)] bisaniline, 4, 4 ′-[1,3-phenylenebis (1-methylethylidene)] bisaniline, bis (p-aminocyclohexyl) methane, bis (p-β-amino-t-butylphenyl) ether, bis (p-β-methyl) -Δ-aminopentyl) benzene, p-bis (2-methyl-4-aminopentyl) benzene, p-bis (1,1-dimethyl-5-aminopentyl) benzene, 1,5-diaminonaphthalene, 2,6 -Diaminonaphthalene, 2,4-bis (β-amino-t-butyl) toluene, 2,4-diaminotoluene, m-xylene-2,5-diamine, p-xylene-2,5-di Examples include amines, m-xylylenediamine, p-xylylenediamine, 2,6-diaminopyridine, 2,5-diaminopyridine, 2,5-diamino-1,3,4-oxadiazole, piperazine and the like. it can.

  The above aromatic diamines may be used alone or in combination of two or more.

(II) Diaminosiloxane:
As diaminosiloxane, diaminosiloxane represented by the following general formula (14) or an oligomer thereof is preferably exemplified.

（ここで、Ｒ_１１及びＲ_１２は２価の炭化水素基を示し、Ｒ_１３〜Ｒ_１６は炭素数１〜６の炭化水素基を示し、ｍ_１は１〜２０の数、好ましくは１〜１０の数を示す。）

(Here, R ₁₁ and R ₁₂ represent a divalent hydrocarbon group, R _{13 to} R ₁₆ represent a hydrocarbon group having 1 to 6 carbon atoms, and m ₁ represents a number of ₁ to 20, preferably 1 to 1. Indicates a number of 10.)

  Examples of such diaminosiloxanes include diaminopropyltetramethyldisiloxane and diaminosiloxanes represented by the above general formulas (5) to (9).

  The above diaminosiloxanes may be used alone or in combination of two or more.

(III) Aliphatic amines:
Examples of the aliphatic amine include 1,4-diaminobutane, 1,5-diaminopentane, 1,6-diaminohexane, 2-methyl-1,5-diaminopentane, 1,7-diaminoheptane, and 1,8. -Diaminooctane, 1,3-bis (aminomethyl) cyclohexane, 1,4-bis (aminomethyl) cyclohexane, 1,9-diaminononane, 1,10-diaminodecane, 1,11-diaminoundecane, 1,12- Diaminoalkanes such as diaminododecane, 4,4′-methylenebiscyclohexylamine, tris (2-aminoethyl) amine, N, N′-bis (2-aminoethyl) -1,3-propanediamine, bis (3 -Aminopropyl) ethylenediamine, 1,4-bis (3-aminopropyl) piperazine, diethylenetriamine, N-methyl-2,2'-dia Nodiethylamine, 3,3′-diaminodipropylamine, amines containing nitrogen atoms such as N, N-bis (3-aminopropyl) methylamine, bis (3-aminopropyl) ether, 1,2-bis Amines containing oxygen atoms such as (2-aminoethoxy) ethane, 3,9-bis (3-aminopropyl) -2,4,8,10-tetraoxaspiro [5.5] -undecane, Examples include amines having a sulfur atom such as 2'-thiobis (ethylamine).

  These aliphatic amines may be used alone or in combination of two or more.

(IV) Dihydrazide compound:
Examples of the dihydrazide compound include those represented by the following general formula (15).

In the general formula (15), examples of R ₁₇ include a single bond, an aliphatic group, and an aromatic group. What is preferable as R ₁₇ is described with reference to examples of dihydrazide compounds. For example, oxalic acid dihydrazide, malonic acid dihydrazide, succinic acid dihydrazide, glutaric acid dihydrazide, adipic acid dihydrazide, pimelic acid dihydrazide, suberic acid dihydrazide, azelaic acid dihydrazide, sebacic acid dihydrazide dihydrazide, maleic acid dihydrazide Diglycolic acid dihydrazide, tartaric acid dihydrazide, malic acid dihydrazide, phthalic acid dihydrazide, isophthalic acid dihydrazide, terephthalic acid dihydrazide, 2,6-naphthoic acid dihydrazide, 4,4-bisbenzenedihydrazide, 1,4-naphthoic acid dihydrazide, 2 , 6-pyridinedihydrazide, itaconic acid dihydrazide and the like.

  The above dihydrazide compounds may be used alone or in combination of two or more.

  Of the amino compounds having at least two primary amino groups as functional groups as described above, dihydrazide compounds are most preferable. When the dihydrazide compound is used, the curing time of the adhesive resin composition can be shortened as compared with the case where another amino compound is used. This is because the product obtained by reacting the primary amino group of the dihydrazide compound with the ketone group has a semicarbazone-like molecular structure, and forms a dimer structure by hydrogen bonding between NHs between molecules. Because the stability of the product is improved, the equilibrium of the reaction is biased toward the product side, and the reverse reaction in the direction of generating the ketone group of the polyimidesiloxane that is the raw material and the amino group of the dihydrazide compound is less likely to occur. It is considered a thing.

  In addition, amino compounds such as (I) aromatic diamine, (II) diaminosiloxane, (III) aliphatic amine, and (IV) dihydrazide compound are, for example, combinations of (I) and (II), (I) and ( It can also be used in combination of two or more types across categories, such as combinations with (III), combinations of (I), (II) and (III), and combinations of (I) to (IV). In particular, by combining the amino compound of (I), (II) or (III) and the dihydrazide compound of (IV) at a predetermined blending ratio, taking advantage of the properties of the amino compound of (I) to (III) It is expected to obtain an effect of shortening the curing time depending on the blending ratio of the dihydrazide compound (IV).

[Production of polyimide resin]
In the polyimide resin of the present invention, an amino compound having at least two primary amino groups as functional groups is added to a resin solution containing polyimide siloxane having the structural units represented by the general formulas (1) and (2). Thus, it is produced by a condensation reaction between a ketone group of polyimide siloxane and a primary amino group of an amino compound. By this condensation reaction, the adhesive resin composition is cured to become a cured product. In this case, the added amount of the amino compound is 0.004 mol to 1.5 mol, preferably 0.005 mol to 1.2 mol, more preferably 0.001 mol to 1.2 mol in total for the primary amino group with respect to 1 mol of the ketone group. It is preferable to add the amino compound so as to be 0.03 mol to 0.9 mol, particularly preferably 0.04 mol to 0.5 mol. Adhesive containing a polyimide resin because the addition of amino compounds such that the total amount of primary amino groups is less than 0.004 moles per mole of ketone groups is insufficient for crosslinking of the polyimide siloxane with the amino compounds. Solder heat resistance tends to be difficult to develop in the cured product after curing the resin composition, and when the added amount of the amino compound exceeds 1.5 mol, the unreacted amino compound acts as a thermoplastic agent and is cured. There is a tendency that the solder heat resistance is lowered in the object, and the long-term heat resistance at high temperature is lowered.

The conditions for the condensation reaction are not particularly limited as long as the ketone group in the polyimidesiloxane and the primary amino group of the amino compound react to form an imine bond (C═N bond). Depending on the type of amino compound, for example, when an aliphatic amine is used, it can be condensed with a ketone group in polyimide siloxane even at room temperature, but it is preferable to promote the condensation reaction by heating. When an aliphatic amine is used, it is preferable to perform heat condensation within a range of 60 to 200 ° C., for example. When an aromatic amine is used, heat condensation is performed within a range of 120 to 220 ° C., for example. preferable. The temperature of the heat condensation is, for example, 120 for the purpose of releasing water generated by the condensation out of the system or simplifying the condensation step when the heat condensation reaction is subsequently performed after the synthesis of the polyimidesiloxane. Within the range of -220 degreeC is preferable, and the inside of the range of 140-200 degreeC is more preferable. The reaction time is preferably about 1 to 24 hours, and the end point of the reaction is 1670 cm by measuring the infrared absorption spectrum using, for example, a Fourier transform infrared spectrophotometer (commercially available product: FT / IR620 manufactured by JASCO Corporation). reduction of the absorption peak derived from the ketone group in the polyimide siloxane near ^-1 or loss, and can be confirmed by the appearance of the absorption peak derived from the imine group 1635cm around ^-1.

The heat condensation of the ketone group of polyimide siloxane and the primary amino group of the amino compound is, for example,
(A) Following the synthesis (imidation) of polyimide siloxane, adding an amino compound and heating,
(B) charging an excess amount of an amino compound in advance as a diamine component and heating the polyimide siloxane together with the remaining amino compound not involved in imidization (or amidation) following the synthesis (imidization) of the polyimide siloxane; Or
(C) heating after processing the polyimidesiloxane composition to which the amino compound has been added into a predetermined shape (for example, after being applied to an arbitrary base material or after being formed into a film),
Etc.

  In the case of (b) above, the excess amino compound is consumed in the reaction of sealing the acid anhydride group as a terminal substituent during the production of polyimidesiloxane, and the molecular weight of the resulting polyimidesiloxane may be extremely reduced. Therefore, it tends to be difficult to obtain sufficient heat resistance in the cured product. Therefore, when an excess amount of an amino compound is charged in advance [the above (b)], it is preferably used as long as the effects of the present invention are not impaired. In order to effectively react at least two primary amino groups in an amino compound with a ketone group to form a C═N bond, the amino compound is synthesized from polyimide siloxane as in (a) or (c) above. It is preferable to add after completing (imidization). In the case of (c) above, the heat condensation is performed by, for example, the heat of heat treatment performed when the adhesive layer of the coverlay film is formed from a composition in which an amino compound and polyimide siloxane are mixed, or the adhesive layer is formed. After that, it can also be performed by using heat at the time of thermocompression bonding to the circuit board having the wiring layer.

  When the polyimide resin of the present invention obtained as described above is used as an adhesive for a coverlay film or the like, the following mathematical formula (iii) is used in order to maintain the adhesive force even when repeatedly placed in a high temperature environment. The P value calculated based on is preferably 0.7 or less, and more preferably 0.6 or less. As shown in Formula (iii), the P value is calculated based on the number of moles and molecular weight of the aromatic tetracarboxylic anhydride residue and aromatic diamine residue in the polyimide resin, and the polar group contained in those residues. Can be determined from the number.

P value = {(A1 + A2) / (B1 + B2)} × 100 (iii)
[Where A1, A2, B1, and B2 have the same meaning as described above, and the number of polar groups is calculated in the same manner as in the case of the p value]

  This P value is an index representing the amount of polar groups contained in the polyimide resin, and the larger the P value, the larger the amount of polar groups in the polyimide resin. When used as an adhesive for a coverlay film or the like, the polar group contained in the adhesive layer becomes a factor inducing copper diffusion from the copper wiring. That is, if a large amount of polar groups are contained in the adhesive layer, copper from the copper wiring diffuses widely into the adhesive layer while heating is repeated. As a result, it is considered that the adhesive strength of the adhesive layer is weakened and the coverlay film is easily peeled off. In the present invention, the P value of the polyimide resin is preferably 0.7 or less (more preferably 0.6 or less), thereby reducing the amount of polar groups contained in the polyimide resin and suppressing the decrease in adhesive force. it can.

In the present invention, the calculation of the P value is carried out by the group Ar (aromatic tetracarboxylic anhydride residue) and the group R ₂ (aromatic group) of polyimidesiloxane having the structural units represented by the general formulas (1) and (2). the reason for polar group contained in the diamine residue) in the basis is the amount of polar groups contained in these groups Ar and in the radical R _2, because the polarity of the entire polyimide resin generally is determined. Therefore, the polar group included in the diaminosiloxane residue or amino compound residue and the polar group involved in the imide bond are not considered in calculating the P value.

[Action]
The reaction between the ketone group of the polyimidesiloxane having the structural units represented by the general formulas (1) and (2) and the primary amino group of the amino compound is a dehydration condensation reaction, and the carbon of the ketone group in the polyimidesiloxane As a result of the atom and the nitrogen atom of the primary amino group forming a C═N bond, it is considered that the chain polyimidesiloxane is crosslinked with an amino compound to form a network polymer. Polyimide siloxane does not easily cause intermolecular interaction, so it is difficult to control the orientation of polyimide siloxane. However, when such a crosslinked structure occurs, not only the apparent increase in molecular weight of polyimide siloxane but also the polyimide siloxane molecules It is considered that the heat resistance of the polyimide resin is improved and extremely excellent solder heat resistance can be obtained. Moreover, the nitrogen atom vicinity in C = N bond becomes three-dimensionally bulky, thereby reducing the nucleophilic ability of the copper atom of the polar group contained in the polyimide resin, thereby reducing the copper adhesive layer from the copper wiring. It is considered that diffusion can be suppressed and an effect of suppressing a decrease in adhesive strength in use in a high temperature environment can be obtained. For these reasons, the amino compound used in the present invention needs to have at least two amino groups, and the number of amino groups is preferably 2 to 5, more preferably 2 to 3. In addition, in an amino compound having three or more amino groups, the cross-linked structure after the two amino groups form a C═N bond becomes three-dimensionally bulky, so that the remaining unreacted amino group is a ketone group. It is particularly preferable that the number of amino groups is 2. Furthermore, from the viewpoint of shortening the curing time of the adhesive resin composition as described above, it is most preferable to use a dihydrazide compound as the amino compound. Further, from the viewpoint of making the network structure formed by crosslinking of the amino compound more dense, the amino compound used in the present invention has a molecular weight (weight average molecular weight when the amino compound is an oligomer) of 5,000 or less. It is preferably 90 to 2,000, more preferably 100 to 1,500. Among these, amino compounds having a molecular weight of 100 to 1,000 are particularly preferable. When the molecular weight of the amino compound is less than 90, one amino group of the amino compound only forms a C = N bond with the ketone group of the polyimide siloxane, and the remaining amino group is sterically bulky so that it remains. The amino group tends to be difficult to bond C═N.

[Adhesive resin composition]
The adhesive resin composition of the present invention comprises a polyimidesiloxane [(A) component] having a structural unit represented by the above general formulas (1) and (2) and at least two primary amino groups as functional groups. And an amino compound [component (B)] as an essential component. This adhesive resin composition is obtained by mixing or kneading the component (A) and the component (B) and / or heating in a state containing the component (A) and the component (B), so that the polyimide siloxane And the primary amino group of the amino compound undergo a condensation reaction to form a C═N bond. That is, it changes to the polyimide resin of the present invention by a condensation reaction between polyimide siloxane and an amino compound. In the adhesive resin composition of the present invention, the weight average molecular weight of the component (A) is preferably 10,000 to 200,000, and more preferably 20,000 to 150,000. When the weight average molecular weight of the component (A) is less than 10,000, it becomes difficult to control the fluidity when the adhesive resin composition is made into a solution, and the heat resistance of the cured product tends to decrease. . On the other hand, when the weight average molecular weight exceeds 200,000, the solubility in the solvent tends to be impaired.

  The adhesive resin composition has a total of primary amino groups of 0.004 mol to 1.5 mol, preferably 0.005 mol to 1.2 mol, more preferably 0.03 mol per mol of ketone groups. An amino compound is contained so that it may become mol-0.9 mol, Most preferably, it is 0.04 mol-0.5 mol.

  The adhesive resin composition of the present invention may contain a plasticizer together with the polyimide siloxane and amino compound. However, some plasticizers contain a large number of polar groups, and there is a concern that this may promote the diffusion of copper from the copper wiring. Therefore, it is preferable not to use the plasticizer as much as possible. Further, in the adhesive resin composition of the present invention, by setting the molar ratio of the diaminosiloxane of the general formula (4) in the total diamine component of the raw material to 75 mol% or more, without adding a plasticizer, Sufficient flexibility can be obtained and warping of the coverlay film can be prevented. For this reason, when using a plasticizer, it is preferable to mix | blend in the range which does not impair the effect of this invention.

  In addition to the polyimide siloxane, amino compound, and optional plasticizer, the adhesive resin composition of the present invention may further include other resin components such as an epoxy resin, a curing accelerator, and a cup as necessary. A ring agent, a filler, a pigment, a solvent, and the like can be appropriately blended. When these optional components are blended, the P value of the entire adhesive resin composition including all optional components can be obtained by the following mathematical formula (iv) obtained by modifying the mathematical formula (iii). Also in this case, the amount of polar groups contained in the adhesive resin composition is reduced by setting the P value of the entire adhesive resin composition to preferably 0.7 or less (more preferably 0.6 or less). , A decrease in adhesive strength can be suppressed.

P value = {(A1 + A2 + An) / (B1 + B2 + Bn)} × 100 (iv)
[Where A1, A2, B1, B2 have the same meaning as above,
An = (number of polar groups in one optional component) × (number of moles of optional component)
Bn = (molecular weight of one arbitrary component) × (number of moles of arbitrary component)
It is assumed that An and Bn are added for each arbitrary component. The number of polar groups in the optional component is calculated in the same manner as in the case of the p value]

  When blending optional components in the adhesive resin composition of the present invention, for example, the total amount of optional components is preferably 1 to 10 parts by weight with respect to 100 parts by weight of the polyimide resin, and 2 to 7 weights. It is more preferable to set it as a blending amount of parts.

  The adhesive resin composition of the present invention obtained as described above has excellent flexibility and thermoplasticity when it is used to form an adhesive layer, such as FPC, rigid flex circuit board, etc. It has preferable characteristics as an adhesive for a coverlay film that protects the wiring part. When used as an adhesive layer of a cover lay film, after applying the adhesive resin composition of the present invention in a solution state (for example, a varnish containing a solvent) on one side of a cover lay film material, for example, 60 to By carrying out thermocompression bonding at a temperature of 220 ° C., the coverlay film of the present invention having a coverlay film material layer and an adhesive layer can be formed. In this case, it is possible to heat-condense the ketone group of the polyimide siloxane and the primary amino group of the amino compound using heat at the time of thermocompression bonding. Moreover, even when heat condensation at the time of thermocompression bonding is not sufficient, heat treatment can be further performed after thermocompression bonding for heat condensation. When heat treatment is performed after thermocompression bonding, the heat treatment temperature is preferably, for example, 60 to 220 ° C, and more preferably 80 to 200 ° C. Moreover, it peels, after apply | coating the adhesive resin composition of this invention in the state of a solution (for example, varnish shape containing a solvent) on arbitrary base materials, for example, drying at the temperature of 80-180 degreeC. The film having the coverlay film material layer and the adhesive layer can also be formed by thermocompression bonding the adhesive film with the coverlay film material at a temperature of 60 to 220 ° C., for example. The coverlay film of the invention can be formed. In this case as well, the ketone group of the polyimide siloxane and the primary amino group of the amino compound can be heat-condensed using the heat during thermocompression bonding. As described above, the adhesive resin composition of the present invention can be used after being processed into various forms in a state where the ketone group of polyimidesiloxane and the primary amino group of the amino compound are unreacted. Furthermore, the adhesive resin composition of the present invention can be used by forming a coating film in the form of a solution by screen printing on an arbitrary substrate and drying it at a temperature of, for example, 80 to 180 ° C. . Preferably, a cured product can be formed by further heat-treating at a temperature of 130 to 220 ° C. for a predetermined time to completely cure the coating film. In this case as well, heat condensation can be performed using heat at the time of curing.

[Coverlay film / bonding sheet]
The film material for the coverlay in the coverlay film of the present invention is not limited, but, for example, a polyimide resin film such as a polyimide resin, a polyetherimide resin, a polyamideimide resin, a polyamide resin film, or a polyester resin. A film or the like can be used. Among these, it is preferable to use a polyimide resin film having excellent heat resistance. The thickness of the coverlay film material layer is not particularly limited, but is preferably 5 μm or more and 100 μm or less, for example. The thickness of the adhesive layer is not particularly limited, but is preferably 10 μm or more and 50 μm or less, for example.

  Moreover, what formed the adhesive resin composition of this invention in the film form can be utilized also as a bonding sheet of multilayer FPC, for example. When used as a bonding sheet, an adhesive film obtained by applying the adhesive resin composition of the present invention in the form of a solution on an arbitrary base film, drying at a temperature of, for example, 80 to 180 ° C., and then peeling. May be used as a bonding sheet as it is, or may be used in a state where this adhesive film is laminated with an arbitrary substrate film. Also when used as a bonding sheet, the heat of thermocompression bonding can be used to heat-condense the polyimidesiloxane ketone group and the primary amino group of the amino compound. Heat condensation can also be performed.

  Moreover, a coverlay film and a bonding sheet are good also as a form which has a release material layer by bonding a release material on the adhesive surface. The material of the release material is not particularly limited as long as it can be peeled without impairing the form of the coverlay film or the bonding sheet. For example, resin films such as polyethylene terephthalate, polyethylene, and polypropylene, and these resin films And the like laminated on paper can be used.

  The cover lay film and bonding sheet obtained by molding using the adhesive resin composition of the present invention and causing the above-mentioned heat condensation reaction by heat treatment are obtained by reacting polyimide resin obtained by reaction of polyimide siloxane and amino compound. Since it contains, it has excellent solder heat resistance. More specifically, as shown in Examples below, the solder heat resistance (drying) is 260 ° C. or higher, preferably 280 ° C. or higher, more preferably 300 ° C. or higher, and the solder heat resistance (humidity resistance) is 200 ° C. or higher. The temperature is preferably 260 ° C. or higher, more preferably 280 ° C. or higher. Thus, by having extremely excellent solder heat resistance, the occurrence of deformation or peeling in the soldering process is prevented, and it is possible to contribute to the improvement of the yield and reliability of the circuit board to be manufactured.

[Circuit board]
As long as the circuit board of this invention is provided with the coverlay film and bonding sheet which are obtained as mentioned above, there is no restriction | limiting in particular in the structure. For example, the preferred form of the circuit board of the present invention includes at least a base material, a wiring layer made of a metal such as copper formed on the base material in a predetermined pattern, and the cover lay film of the present invention covering the wiring layer. And. The base material of the circuit board is not particularly limited, but in the case of FPC, the same material as the coverlay film material is preferably used, and the base material made of polyimide resin is preferably used.

By using the cover lay film of the present invention, the circuit board of the present invention is filled with an adhesive layer having excellent flexibility and thermoplasticity between the wirings, and high adhesion between the cover lay film and the wiring layer is obtained. It is done. In addition, by forming an adhesive layer containing a polyimide resin obtained by the reaction of polyimide siloxane and an amino compound, copper diffusion from the copper wiring is suppressed, and even if repeated use in a high temperature environment is excellent Adhesion can be maintained over a long period of time. More specifically, after a long-term heat resistance test at 150 ° C. and 1000 hours in the atmosphere, the measurement of the energy dispersive X-ray (EDX) analyzer (see Examples below) shows that the copper on the adhesive layer The amount of diffusion can be suppressed to 2.5% or less. As a result, it is possible to maintain the peel strength between the copper wiring layer and the coverlay film material layer after the long-term heat resistance test at 0.2 kN / m or more. In particular, by selecting the group Ar, the group R ₁ and the group R ₂ in the general formulas (1) and (2), it is possible to obtain an extremely high peel strength of 0.4 kN / m or more. In addition, by setting the blending ratio of diaminosiloxane to the total diamine component of the raw material to 75 mol% or more, it is possible to obtain excellent solubility and prevent warping of the coverlay film without blending a plasticizer. it can.

  The circuit board of the present invention may be configured as a multilayer circuit board. In this case, the adhesive film obtained from the adhesive resin composition of the present invention can be used not only for the coverlay film but also for the bonding sheet.

  The production of the circuit board of the present invention is not particularly limited. For example, after the metal foil of a metal-clad laminate such as a copper-clad laminate is processed into a predetermined pattern by a method such as chemical etching, the circuit is produced. For example, a method of laminating a cover lay film on the necessary portion above and performing thermocompression bonding using, for example, a hot press apparatus can be used. In this case, the pressure bonding conditions are not particularly limited. For example, the pressure bonding temperature is preferably 130 ° C. or higher and 220 ° C. or lower, more preferably 140 ° C. or higher and 200 ° C. or lower, and the pressure is 0.1 MPa or higher and 4 MPa or lower. It is preferable. In addition, when the ketone group of polyimide siloxane and the primary amino group of the amino compound are unreacted in the state of the cover lay film, condensation is performed using heat when the cover lay film is thermocompression bonded to the circuit wiring. A reaction can be caused. That is, it arrange | positions so that the adhesive bond layer of a coverlay film may contact | connect a wiring layer, and the process of carrying out the thermocompression bonding of both members, and the ketone group of (A) component contained in an adhesive bond layer, and (B) component It is possible to carry out a condensation reaction with a primary amino group to form a C═N bond.

  EXAMPLES Hereinafter, the present invention will be specifically described with reference to examples, but the present invention is not limited to these examples. In the following examples, various measurements and evaluations are as follows unless otherwise specified.

[Measurement of adhesive strength]
The adhesive strength of the test piece cut out to a width of 10 mm and a length of 100 mm was placed on a glossy surface of copper foil (thickness of 35 μm) (with rust-proof metal removed), temperature 170 ° C., pressure 1 MPa, Pressed under the conditions of 1 minute for the time, and then heated in the oven at the temperature of 150 ° C. for the time of 24 hours (however, for Example 21, thermocompression bonding was performed at the temperature of 200 ° C., the pressure of 1 MPa, the time of 60 minutes, After the subsequent heat treatment is omitted), a tensile tester (manufactured by Toyo Seiki Co., Ltd., Strograph-M1) is used to determine the force at the time of peeling at a speed of 50 mm / min in the 180 ° direction as the adhesive strength. In this experiment, the case where the adhesive strength was 0.2 kN / m or more was determined as “good”, and the case where it was 0.35 kN / m or more was determined as “good”.

[Measurement of weight average molecular weight (Mw)]
The weight average molecular weight was measured by a gel permeation chromatograph (manufactured by Tosoh Corporation, using HLC-8220GPC). Polystyrene was used as a standard substance, and N, N-dimethylacetamide was used as a developing solvent.

[Evaluation method of warpage]
The warpage was evaluated by the following method. A polyimide adhesive was applied onto a 25 μm thick Kapton film so that the thickness after drying was 35 μm. In this state, the Kapton film was placed on the lower surface, and the average of the heights at which the four corners of the film were warped was measured.

[Method for evaluating solder heat resistance (drying)]
A circuit of polyimide copper-clad laminate (manufactured by Nippon Steel Chemical Co., Ltd., trade name: Espanex MC18-25-00FRM) was formed, and a circuit with wiring width / wiring interval (L / S) = 1 mm / 1 mm was formed. A printed circuit board is prepared, and the adhesive surface of the test piece is placed on the wiring of the printed circuit board, pressed under conditions of a temperature of 170 ° C., a pressure of 1 MPa, and an hour of 1 minute, and then heated in an oven at a temperature of 150 ° C. for an hour of 24 hours. The sample was heated under the conditions (however, in Example 21, thermocompression bonding was performed under the conditions of a temperature of 200 ° C., a pressure of 1 MPa, and a time of 60 minutes, and the subsequent heat treatment was omitted). This test piece with copper foil was left at 105 ° C. and 50% relative humidity for 1 hour, then immersed in a solder bath set to each evaluation temperature for 10 seconds, and observed for adhesion, foaming, blistering and peeling. The presence or absence of such defects was confirmed. The heat resistance is expressed by an upper limit temperature at which no defect occurs. For example, “320 ° C.” means that no defect is observed when evaluated in a solder bath at 320 ° C. (see Tables 2 to 4 below).

[Method for evaluating solder heat resistance (moisture resistance)]
A circuit of polyimide copper-clad laminate (manufactured by Nippon Steel Chemical Co., Ltd., trade name: Espanex MC18-25-00FRM) was formed, and a circuit with wiring width / wiring interval (L / S) = 1 mm / 1 mm was formed. A printed circuit board is prepared, and the adhesive surface of the test piece is placed on the wiring of the printed circuit board, pressed under conditions of a temperature of 170 ° C., a pressure of 1 MPa, and an hour of 1 minute, and then heated in an oven at a temperature of 150 ° C. for an hour of 24 hours. The sample was heated under the conditions (however, in Example 21, thermocompression bonding was performed under the conditions of a temperature of 200 ° C., a pressure of 1 MPa, and a time of 60 minutes, and the subsequent heat treatment was omitted). The test piece with the copper foil was allowed to stand at 85 ° C. and a relative humidity of 85% for 24 hours, then immersed in a solder bath set to each evaluation temperature for 10 seconds, and observed for adhesion, foaming, blistering and peeling. The presence or absence of such defects was confirmed. The heat resistance is expressed by an upper limit temperature at which no defect occurs. For example, “280 ° C.” means that no defect is observed when evaluated in a solder bath at 280 ° C. (see Tables 2 to 4 below).

[Tensile test]
A sample made of a polyimide resin film having a thickness of 35 μm was cut into a strip shape having a width of 12.5 mm and a length of 120 mm to obtain a test piece, and a tensile testing machine (Strograph-R1 manufactured by Toyo Seiki Co., Ltd.) was used. Then, measurement is performed at a crosshead speed of 25 mm / min and a distance between chucks of 101.6 mm, and the value obtained by dividing the measurement load by the cross-sectional area (0.31 mm ² ) of the test piece is taken as the tensile strength.

The abbreviations used in the examples represent the following compounds.
BTDA: 3,3 ′, 4,4′-benzophenonetetracarboxylic dianhydride (BTDA polar group; 1, p value = 0.56)
BPDA: 3,3 ′, 4,4′-diphenyltetracarboxylic dianhydride (BPDA polar group; 0, p value = 0)
BAPP: 2,2-bis (4-aminophenoxyphenyl) propane (polar group of BAPP; 2, p value = 0.53)
DAPE: 4,4′-diaminodiphenyl ether TPE-R: 1,3-bis (4-aminophenoxy) benzene p-PDA: p-phenylenediamine m-TB: 2,2′-dimethyl-4,4′-diamino Biphenyl BAFL: Bisaniline fluorene HMDA: 1,6-hexamethylenediamine PSX-A: Diaminosiloxane represented by the above formula (5) (However, the number average value of m ₁ is in the range of 1 to 20, and the weight. The average molecular weight is 740)
N-12: dodecanedioic acid dihydrazide _{(R 17} is _C 10 _{H 20} in the formula (15))
ADH: adipic acid dihydrazide (R ₁₇ in the above formula (15) is C ₄ H ₈ )

Synthesis example 1
In a 1000 ml separable flask, 71.30 g PSX-A (0.0964 mol), 9.89 g BAPP (0.0241 mol), 38.66 g BTDA (0.120 mol), 168 g N-methyl. 2-Pyrrolidone and 112 g of xylene were charged and mixed well at room temperature for 1 hour to obtain a polyamic acid solution. This polyamic acid solution was heated to 190 ° C., heated and stirred for 20 hours to obtain a polyimide solution a having completed imidization. The weight average molecular weight (Mw) of the polyimide resin in the obtained polyimide solution a was 122,000. At this time, the mol% of the diaminosiloxane component relative to the total diamine component is 80% (m value = 0.8). In addition, "m value" means the presence molar ratio of the structural unit represented by the said General formula (1) contained in the obtained polyimide resin (hereinafter the same). Moreover, P value which is a parameter | index showing the quantity of the polar group contained in the obtained polyimide resin is 0.55.

Synthesis example 2
In a 1000 ml separable flask, 71.30 g PSX-A (0.0964 mol), 9.89 g BAPP (0.0241 mol), 38.66 g BTDA (0.120 mol), 168 g N-methyl. 2-Pyrrolidone and 112 g of xylene were charged and mixed well at room temperature for 1 hour to obtain a polyamic acid solution. This polyamic acid solution was heated to 190 ° C., heated and stirred for 6 hours to obtain a polyimide solution b in which imidization was completed. The weight average molecular weight (Mw) of the polyimide resin in the obtained polyimide solution b was 36,700. The mol% of the diaminosiloxane component with respect to the total diamine component at this time is 80% (m value = 0.8). Moreover, P value which is a parameter | index showing the quantity of the polar group contained in the obtained polyimide resin is 0.55.

Synthesis example 3
In a 1000 ml separable flask, 73.41 g PSX-A (0.0992 mol), 10.21 g BAPP (0.0249 mol), 36.46 g BPDA (0.1239 mol), 168 g N-methyl. 2-Pyrrolidone and 112 g of xylene were charged and mixed well at room temperature for 1 hour to obtain a polyamic acid solution. This polyamic acid solution was heated to 190 ° C., heated and stirred for 6 hours to obtain a polyimide solution c in which imidization was completed. The weight average molecular weight (Mw) of the polyimide resin in the obtained polyimide solution c was 27,900. At this time, the mol% of the diaminosiloxane component relative to the total diamine component is 80% (m value = 0.8). Moreover, P value which is a parameter | index showing the quantity of the polar group contained in the obtained polyimide resin is 0.18.

  Synthesis Examples 1 to 3 are summarized in Table 1.

Reference example 1
The polyimide solution a obtained in Synthesis Example 1 is applied to one side of a polyimide film (manufactured by DuPont, trade name: Kapton ENS, length × width × thickness = 200 mm × 300 mm × 25 μm), and dried at 80 ° C. for 15 minutes. A coverlay film having an adhesive layer thickness of 35 μm was obtained. Absorption of a ketone group derived from BTDA near 1673 cm ⁻¹ by measuring the infrared absorption spectrum of the adhesive layer in the coverlay film using a Fourier transform infrared spectrophotometer (commercial product: FT / IR620 manufactured by JASCO) It was confirmed. Next, the obtained cover lay film is placed on a copper foil from which the surface anticorrosive metal layer has been removed, pressed under conditions of a temperature of 170 ° C., a pressure of 1 MPa, and an hour of 1 minute, and then in an oven at a temperature of 150 ° C. for an hour. It heated on the conditions for 24 hours and obtained the evaluation sample. The evaluation results are shown in Table 2.

[Example 1]
To the polyimide solution a obtained in Synthesis Example 1, 5.78 g of BAPP (0.014 mol) was blended and further stirred for 1 hour to obtain a polyimide solution 1.

The obtained polyimide solution 1 was applied to one side of a polyimide film (manufactured by DuPont, trade name: Kapton ENS, length × width × thickness = 200 mm × 300 mm × 25 μm), dried at 80 ° C. for 15 minutes, and adhesive A coverlay film 1 having a layer thickness of 35 μm was obtained. This cover lay film 1 is placed on a copper foil from which the anticorrosive metal layer has been removed, pressed at a temperature of 170 ° C., a pressure of 1 MPa, and a time of 1 minute, and then in an oven at a temperature of 150 ° C. and a time of 24 hours. And an evaluation sample 1 was obtained. The adhesive strength between the copper foil after curing the adhesive layer and the coverlay film was 1.9 kN / m. Moreover, the warp of the coverlay film was no problem. When the infrared absorption spectrum of the adhesive layer in the evaluation sample 1 was measured using a Fourier transform infrared spectrophotometer (commercially available product: FT / IR620 manufactured by JASCO Corporation), the absorption of the ketone group derived from BTDA was observed in the vicinity of 1673 cm ^−1. It was confirmed that it decreased, and absorption of an imine group was further confirmed in the vicinity of 1635 cm ⁻¹ .

  Next, the evaluation sample 1 was heat-treated in an oven at 150 ° C. for 1000 hours in an oven. It was 0.80 kN / m when the copper foil after a process and the adhesive strength of a coverlay film were measured. The peeling surface at this time was an interface between copper and the adhesive layer.

  Further, a printed board having a circuit {wiring width / wiring interval (L / S) = 25 μm / 25 μm} formed of copper on both sides of the polyimide film is prepared. The coverlay film 1 obtained in Example 1 is printed board. Placed on the circuit surface, pressed at a temperature of 170 ° C., a pressure of 1 MPa, and a time of 1 minute, and then heated in an oven at a temperature of 150 ° C. and a time of 24 hours to obtain a wiring board 1 provided with a coverlay film. It was.

[Example 2]
After obtaining the polyimide solution 2 in the same manner as in Example 1 except that 5.78 g of DAPE (0.029 mol) was added instead of 5.78 g of BAPP in Example 1. The coverlay film 2 was obtained and the evaluation sample 2 was obtained. The adhesive strength between the copper foil after curing of the adhesive layer and the coverlay film was 1.55 kN / m. Moreover, the warp of the coverlay film was no problem.

  Next, heat treatment was performed on the evaluation sample 2 in an oven in the air at 150 ° C. for 1000 hours. It was 0.63 kN / m when the copper foil after a process and the adhesive strength of a coverlay film were measured. The peeling surface at this time was an interface between copper and the adhesive layer.

  Further, in the same manner as in Example 1, a printed circuit board on which a circuit {wiring width / wiring interval (L / S) = 25 μm / 25 μm} is prepared, and the coverlay film 2 obtained in Example 2 is printed. It was placed on the circuit surface of the substrate and thermocompression bonded to obtain a wiring substrate 2 provided with a coverlay film.

[Example 3]
A polyimide solution 3 was obtained in the same manner as in Example 1 except that 5.78 g of p-PDA (0.053 mol) was added instead of 5.78 g of BAPP in Example 1. After that, a coverlay film 3 was obtained, and an evaluation sample 3 was obtained. The adhesive strength between the copper foil after curing of the adhesive layer and the coverlay film was 1.0 kN / m. Moreover, the warp of the coverlay film was no problem.

  Next, the evaluation sample 3 was heat-treated in an oven at 150 ° C. for 1000 hours in the atmosphere. It was 0.54 kN / m when the copper foil after a process and the adhesive strength of the coverlay film were measured. The peeling surface at this time was an interface between copper and the adhesive layer.

  Further, in the same manner as in Example 1, a printed circuit board on which a circuit {wiring width / wiring interval (L / S) = 25 μm / 25 μm} is prepared, and the coverlay film 3 obtained in Example 3 is printed. Placed on the circuit surface of the substrate and thermocompression bonded, a wiring substrate 3 provided with a coverlay film was obtained.

[Example 4]
A polyimide solution 4 was obtained in the same manner as in Example 1 except that 5.78 g of m-TB (0.027 mol) was added instead of 5.78 g of BAPP in Example 1. After that, a coverlay film 4 was obtained, and an evaluation sample 4 was obtained. The adhesive strength between the copper foil after curing of the adhesive layer and the copper foil of the coverlay film was 1.18 kN / m. Moreover, the warp of the coverlay film was no problem.

  Next, the evaluation sample 4 was heat-treated in an oven in the atmosphere at 150 ° C. for 1000 hours. It was 0.46 kN / m when the copper foil after a process and the adhesive strength of a coverlay film were measured. The peeling surface at this time was an interface between copper and the adhesive layer.

  Further, similarly to Example 1, a printed circuit board on which a circuit {wiring width / wiring interval (L / S) = 25 μm / 25 μm} is prepared, and the coverlay film 4 obtained in Example 4 is printed. Placed on the circuit surface of the substrate and thermocompression bonded, a wiring substrate 4 provided with a coverlay film was obtained.

[Example 5]
A polyimide solution 5 was obtained in the same manner as in Example 1 except that 5.78 g of TPE-R (0.020 mol) was added instead of 5.78 g of BAPP in Example 1. After that, a coverlay film 5 was obtained, and an evaluation sample 5 was obtained. The adhesive strength between the copper foil after curing of the adhesive layer and the coverlay film was 2.0 kN / m. Moreover, the warp of the coverlay film was no problem.

  Next, heat treatment was performed on the evaluation sample 5 in an oven in the air at 150 ° C. for 1000 hours. It was 0.66 kN / m when the copper foil after a process and the adhesive strength of the coverlay film were measured. The peeling surface at this time was an interface between copper and the adhesive layer.

  Further, a printed circuit board on which a circuit {wiring width / wiring interval (L / S) = 25 μm / 25 μm} is prepared in the same manner as in Example 1, and the coverlay film 5 obtained in Example 5 is printed. Placed on the circuit surface of the substrate and thermocompression bonded, a wiring substrate 5 provided with a coverlay film was obtained.

[Example 6]
After obtaining polyimide solution 6 in the same manner as in Example 1, except that 5.78 g of BAPP in Example 1 was blended instead of 5.78 g of BAFL (0.017 mol). The coverlay film 6 was obtained and the evaluation sample 6 was obtained. The adhesive strength between the copper foil after curing of the adhesive layer and the coverlay film was 1.22 kN / m. Moreover, the warp of the coverlay film was no problem.

  Next, the evaluation sample 6 was heat-treated in the atmosphere at 150 ° C. for 1000 hours in an oven. It was 0.65 kN / m when the copper foil after a process and the adhesive strength of a coverlay film were measured. The peeling surface at this time was an interface between copper and the adhesive layer.

  Further, similarly to Example 1, a printed circuit board on which a circuit {wiring width / wiring interval (L / S) = 25 μm / 25 μm} is prepared, and the coverlay film 6 obtained in Example 6 is printed. Placed on the circuit surface of the substrate and thermocompression bonded, a wiring substrate 6 provided with a coverlay film was obtained.

Reference example 2
A polyimide solution to which BAPP was added was obtained in the same manner as in Example 1 except that the polyimide solution c obtained in Synthesis Example 3 was used instead of the polyimide solution a in Example 1. This polyimide solution is applied to one side of a polyimide film (DuPont, trade name: Kapton ENS, length x width x thickness = 200 mm x 300 mm x 25 µm), dried at 80 ° C for 15 minutes, and the thickness of the adhesive layer A 35 μm coverlay film was obtained. The coverlay film was evaluated in the same manner as in Example 1.

  The results of Examples 1 to 6 and Reference Examples 1 and 2 are summarized in Table 2. In Table 2, adhesive strength 1 indicates the adhesive strength between the copper foil after curing of the adhesive layer and the coverlay film, and adhesive strength 2 indicates the copper foil and coverlay after heat treatment at 150 ° C. in air for 1000 hours. The adhesive strength with the film is shown (the same applies to Tables 4 and 5). In addition, the molar ratio in Table 2 means the total molar ratio of the primary amino group in the amino compound to 1 mole of the ketone group in the polyimidesiloxane (the same applies to Tables 3, 4 and 5). ).

[Example 7]
A cover lay film 7 is obtained after obtaining a polyimide solution 7 in the same manner as in Example 1 except that the polyimide solution b obtained in Synthesis Example 2 is used instead of the polyimide solution a in Example 1. Evaluation sample 7 was obtained. The evaluation results are shown in Table 3.

  Further, in the same manner as in Example 1, a printed circuit board on which a circuit {wiring width / wiring interval (L / S) = 25 μm / 25 μm} is prepared, and the coverlay film 7 obtained in Example 7 is printed. Placed on the circuit surface of the substrate and thermocompression bonded, a wiring substrate 7 provided with a coverlay film was obtained.

[Example 8]
Instead of the polyimide solution a in Example 2, the polyimide solution 8 was obtained in the same manner as in Example 2 except that the polyimide solution b obtained in Synthesis Example 2 was used, and then the coverlay film 8 was obtained. Evaluation sample 8 was obtained. The evaluation results are shown in Table 3.

  Further, similarly to Example 1, a printed circuit board on which a circuit {wiring width / wiring interval (L / S) = 25 μm / 25 μm} is prepared, and the coverlay film 8 obtained in Example 8 is printed. Placed on the circuit surface of the substrate and thermocompression bonded, a wiring substrate 8 provided with a coverlay film was obtained.

[Example 9]
Instead of the polyimide solution a in Example 3, the polyimide solution 9 was obtained in the same manner as in Example 3 except that the polyimide solution b obtained in Synthesis Example 2 was used, and then the coverlay film 9 was obtained. Evaluation sample 9 was obtained. The evaluation results are shown in Table 3.

  Further, in the same manner as in Example 1, a printed circuit board on which a circuit {wiring width / wiring interval (L / S) = 25 μm / 25 μm} is prepared, and the coverlay film 9 obtained in Example 9 is printed. Placed on the circuit surface of the substrate and thermocompression bonded, a wiring substrate 9 provided with a coverlay film was obtained.

[Example 10]
Instead of the polyimide solution a in Example 4, the polyimide solution 10 was obtained in the same manner as in Example 4 except that the polyimide solution b obtained in Synthesis Example 2 was used, and then the coverlay film 10 was obtained. Evaluation sample 10 was obtained. The evaluation results are shown in Table 3.

  Further, in the same manner as in Example 1, a printed circuit board on which a circuit {wiring width / wiring interval (L / S) = 25 μm / 25 μm} is prepared, and the coverlay film 10 obtained in Example 10 is printed. Placed on the circuit surface of the substrate and thermocompression bonded, a wiring substrate 10 provided with a coverlay film was obtained.

[Example 11]
A cover lay film 11 is obtained after obtaining a polyimide solution 11 in the same manner as in Example 5 except that the polyimide solution b obtained in Synthesis Example 2 is used instead of the polyimide solution a in Example 5. Evaluation sample 11 was obtained. The evaluation results are shown in Table 3.

  Further, a printed circuit board on which a circuit {wiring width / wiring interval (L / S) = 25 μm / 25 μm} is prepared in the same manner as in Example 1, and the coverlay film 11 obtained in Example 11 is printed. It was placed on the circuit surface of the substrate and thermocompression bonded to obtain a wiring substrate 11 provided with a coverlay film.

[Example 12]
Instead of the polyimide solution a in Example 6, the polyimide solution 12 was obtained in the same manner as in Example 6 except that the polyimide solution b obtained in Synthesis Example 2 was used, and then the coverlay film 12 was obtained. Evaluation sample 12 was obtained. The evaluation results are shown in Table 3.

  Further, in the same manner as in Example 1, a printed circuit board on which a circuit {wiring width / wiring interval (L / S) = 25 μm / 25 μm} is prepared, and the coverlay film 12 obtained in Example 12 is printed. Placed on the circuit surface of the substrate and thermocompression bonded, a wiring substrate 12 provided with a coverlay film was obtained.

Reference example 3
The polyimide solution b obtained in Synthesis Example 2 is applied to one side of a polyimide film (manufactured by DuPont, trade name: Kapton ENS, length × width × thickness = 200 mm × 300 mm × 25 μm), and dried at 80 ° C. for 15 minutes. A coverlay film having an adhesive layer thickness of 35 μm was obtained. The coverlay film was evaluated in the same manner as in Example 1. The evaluation results are shown in Table 3.

  The results of Examples 7 to 12 and Reference Example 3 are summarized in Table 3.

[Example 13]
After obtaining polyimide solution 13 in the same manner as in Example 1 except that 0.18 g of BAPP (0.28 mmol) was added instead of 5.78 g of BAPP in Example 1. The coverlay film 13 was obtained and the evaluation sample 13 was obtained. The evaluation results are shown in Table 4.

[Example 14]
After obtaining polyimide solution 14 in the same manner as in Example 1 except that 0.58 g of BAPP (1.4 mmol) was blended instead of blending 5.78 g of BAPP in Example 1. The coverlay film 14 was obtained, and the evaluation sample 14 was obtained. The evaluation results are shown in Table 4.

[Example 15]
After obtaining polyimide solution 15 in the same manner as in Example 1 except that 1.78 g of BAPP (2.8 mmol) was blended instead of blending 5.78 g of BAPP in Example 1. The coverlay film 15 was obtained, and the evaluation sample 15 was obtained. The evaluation results are shown in Table 4.

[Example 16]
After obtaining the polyimide solution 16 in the same manner as in Example 1 except that 3.46 g of BAPP (8.4 mmol) was blended instead of blending 5.78 g of BAPP in Example 1. The coverlay film 16 was obtained and the evaluation sample 16 was obtained. The evaluation results are shown in Table 4.

[Example 17]
After obtaining polyimide solution 17 in the same manner as in Example 1 except that 11.53 g of BAPP (0.028 mol) was added instead of 5.78 g of BAPP in Example 1. The coverlay film 17 was obtained and the evaluation sample 17 was obtained. The evaluation results are shown in Table 4.

[Example 18]
After the polyimide solution 18 was obtained in the same manner as in Example 1 except that 17.29 g of BAPP (0.042 mol) was added instead of 5.78 g of BAPP in Example 1. The coverlay film 18 was obtained and the evaluation sample 18 was obtained. The evaluation results are shown in Table 4.

[Example 19]
After obtaining polyimide solution 19 in the same manner as in Example 1 except that 5.78 g of BAPP in Example 1 was blended instead of blending 23.05 g of BAPP (0.056 mol). The coverlay film 19 was obtained, and the evaluation sample 19 was obtained. The evaluation results are shown in Table 4.

[Example 20]
After obtaining polyimide solution 20 in the same manner as in Example 1 except that 28.82 g of BAPP (0.070 mol) was blended instead of blending 5.78 g of BAPP in Example 1. The coverlay film 20 was obtained and the evaluation sample 20 was obtained. The evaluation results are shown in Table 4.

[Example 21]
To the polyimide solution a obtained in Synthesis Example 1, 5.78 g of BAPP (0.014 mol) was blended, and further stirred for 1 hour to obtain a polyimide solution 21.

The obtained polyimide solution 21 was applied to one side of a polyimide film (manufactured by DuPont, trade name: Kapton ENS, length × width × thickness = 200 mm × 300 mm × 25 μm), dried at 80 ° C. for 15 minutes, and adhesive A coverlay film 21 having a layer thickness of 35 μm was obtained. The cover lay film 21 was placed on a copper foil from which the rust-proof metal layer was removed, and thermocompression bonded under the conditions of a temperature of 200 ° C., a pressure of 1 MPa, and a time of 60 minutes. The adhesive strength between the copper foil after curing of the adhesive layer and the coverlay film was 2.0 kN / m. Moreover, the warp of the coverlay film was no problem. Measurement of the infrared absorption spectrum of the adhesive layer in the evaluation sample 21, it is confirmed that the absorption of ketone group of BTDA from around 1673cm ^-1 is reduced, further absorption confirmation of the imine group near 1635 cm ^-1 It was done. From this measurement result, in the evaluation sample 21, it is presumed that the condensation reaction between the ketone group in the polyimide resin and the amino compound (BAPP) occurred simultaneously with the thermocompression bonding of the coverlay film and the copper foil. The evaluation results of the evaluation sample 21 are shown in Table 4.

  The results of Examples 13 to 21 are summarized in Table 4.

  From Tables 2 to 4, after the amino compound was added to the polyimide resin, the cover lay films of Examples 1 to 21 in which the condensation reaction between the ketone group and the amino compound in the polyimide resin was caused, were all solder heat resistant. (Dry) is 280 ° C. or higher, solder heat resistance (humidity resistance) is 260 ° C. or higher, and excellent adhesion strength significantly exceeding 0.2 kN / m even after heat treatment in air at 150 ° C. for 1000 hours is obtained. It was. Moreover, the curvature of the coverlay film was also suppressed.

[Example 22]
1.16 g of N-12 (0.004 mol) was added to the polyimide solution a obtained in Synthesis Example 1, and the mixture was further stirred for 1 hour to obtain a polyimide solution 22.

The obtained polyimide solution 1 was applied to one side of a polyimide film (manufactured by DuPont, trade name: Kapton ENS, length × width × thickness = 200 mm × 300 mm × 25 μm), dried at 80 ° C. for 15 minutes, and adhesive A coverlay film 22 having a layer thickness of 35 μm was obtained. This cover lay film 22 is placed on a copper foil from which the surface rust-proof metal layer has been removed, pressed under conditions of a temperature of 170 ° C., a pressure of 1 MPa, and a time of 1 minute, and then in an oven at a temperature of 150 ° C. and a time of 6 hours And an evaluation sample 22 was obtained. There was no problem with the warping of the coverlay film. When the infrared absorption spectrum of the adhesive layer in the evaluation sample 1 was measured using a Fourier transform infrared spectrophotometer (commercially available product: FT / IR620 manufactured by JASCO Corporation), the absorption of the ketone group derived from BTDA was observed in the vicinity of 1673 cm ^−1. It was confirmed that it decreased.

  The adhesive strength between the copper foil after the adhesive layer curing of the evaluation sample 22 and the coverlay film was 1.85 kN / m. Next, the evaluation sample 22 was heat-treated in an oven at 150 ° C. for 1000 hours in the air. It was 0.73 kN / m when the copper foil after a process and the adhesive strength of a coverlay film were measured.

[Example 23]
A polyimide solution 23 was prepared in the same manner as in Example 22 except that 3.16 g of N-12 (0.013 mol) was blended instead of blending 1.16 g of N-12 in Example 22. After that, a coverlay film 23 was obtained, and an evaluation sample 23 was obtained.

  The adhesive strength between the copper foil and the cover lay film after curing of the adhesive layer of Evaluation Sample 23 was 1.62 kN / m. Next, the evaluation sample 23 was heat-treated in an oven at 150 ° C. for 1000 hours in the air. It was 0.62 kN / m when the copper foil after a process and the adhesive strength of a coverlay film were measured.

[Example 24]
A polyimide solution 24 was obtained in the same manner as in Example 22 except that 5.78 g of N-12 (0.022 mol) was blended instead of blending 1.16 g of N-12 in Example 22. After that, a coverlay film 24 was obtained, and an evaluation sample 24 was obtained.

  The adhesive strength between the copper foil after the adhesive layer curing of the evaluation sample 24 and the coverlay film was 1.36 kN / m. Next, the evaluation sample 24 was heat-treated in an oven in the atmosphere at 150 ° C. for 1000 hours. It was 0.58 kN / m when the copper foil after a process and the adhesive strength of the coverlay film were measured.

[Example 25]
A polyimide solution 25 was obtained in the same manner as in Example 22 except that 1.16 g of ADH (0.007 mol) was added instead of 1.16 g of N-12 in Example 22. After that, a coverlay film 25 was obtained, and an evaluation sample 25 was obtained.

  The adhesive strength between the copper foil and the cover lay film after curing of the adhesive layer of the evaluation sample 25 was 1.65 kN / m. Next, the evaluation sample 25 was heat-treated in an oven in the atmosphere at 150 ° C. for 1000 hours. It was 0.7 kN / m when the adhesive strength of the copper foil after a process and a coverlay film was measured.

[Example 26]
A polyimide solution 26 was obtained in the same manner as in Example 22 except that 3.16 g of ADH (0.020 mol) was added instead of 1.16 g of N-12 in Example 22. After that, a coverlay film 26 was obtained, and an evaluation sample 26 was obtained.

  The adhesive strength between the copper foil and the cover lay film after curing of the adhesive layer of the evaluation sample 26 was 1.32 kN / m. Next, the evaluation sample 26 was heat-treated in an oven at 150 ° C. for 1000 hours in the air. It was 0.56 kN / m when the copper foil after a process and the adhesive strength of the coverlay film were measured.

[Example 27]
A polyimide solution 27 was obtained in the same manner as in Example 22 except that 5.16 g of ADH (0.033 mol) was added instead of 1.16 g of N-12 in Example 22. After that, a coverlay film 27 was obtained, and an evaluation sample 27 was obtained.

  The adhesive strength between the copper foil after the adhesive layer curing of the evaluation sample 27 and the coverlay film was 1.02 kN / m. Next, the evaluation sample 27 was heat-treated in an oven at 150 ° C. for 1000 hours in the air. It was 0.48 kN / m when the copper foil after a process and the adhesive strength of a coverlay film were measured.

Reference example 4
A coverlay film was obtained in the same manner as in Example 1. The obtained cover lay film was placed on a copper foil from which the rust-proof metal layer on the surface was removed, pressed under conditions of a temperature of 170 ° C., a pressure of 1 MPa, and an hour of 1 minute, and then heated in an oven at a temperature of 150 ° C. for an hour of 6 hours. The sample was heated under conditions to obtain an evaluation sample. The evaluation results are shown in Table 5.

  The results of Examples 22 to 27 and Reference Example 4 are summarized in Table 5.

  From Table 5, after adding a dihydrazide compound to a polyimide resin, the cover lay films of Examples 22 to 27 in which a condensation reaction between a ketone group and an amino compound in the polyimide resin was caused to significantly increase the curing time after pressing. Despite shortening, both have solder heat resistance (dry) of 260 ° C. or higher, solder heat resistance (humidity resistance) of 200 ° C. or higher, and 0.2 kN even after heat treatment in air at 150 ° C. for 1000 hours. Excellent adhesive strength significantly exceeding / m was obtained. Moreover, the curvature of the coverlay film was also suppressed.

  As mentioned above, although embodiment of this invention was described in detail for the purpose of illustration, this invention is not restrict | limited to the said embodiment. Those skilled in the art can make many modifications without departing from the spirit and scope of the present invention, and these are also included within the scope of the present invention. For example, in the above embodiment, the polyimide resin of the present invention has been exemplified by adhesives for circuit board coverlay films and bonding sheets such as FPC, but other uses such as tape automated bonding. (TAB), chip size package (CSP) and the like can be used for forming an adhesive resin.

Claims (20)

Structural units represented by the following general formulas (1) and (2):

[Wherein Ar is a tetravalent aromatic group derived from an aromatic tetracarboxylic acid anhydride, R ₁ is a divalent diaminosiloxane residue derived from diaminosiloxane, and R ₂ is derived from an aromatic diamine. Each represents a divalent aromatic diamine residue, Ar and / or R ₂ contains a ketone group, m and n represent the molar ratio of each constituent unit, and m is from 0.75 to 1.0. N is in the range of 0 to 0.25 . However, when n is 0, Ar contains the ketone group. ]
The total number of amino groups of the amino compound having at least two primary amino groups as a functional group is 0.1% with respect to 1 mol of the ketone group in the polyimidesiloxane having a weight average molecular weight of 10,000 to 200,000 . The said amine compound is mix | blended so that it may become in the range of 004 mol-1.5 mol, The said ketone group and the said amino group react, and the said polyimidesiloxane is formed by forming the C = N bond. A polyimide resin having a structure crosslinked with the amino compound.   The polyimide resin according to claim 1, wherein in the general formula (2), n is at least 0.2.   The polyimide resin according to claim 1, wherein the amino compound is a dihydrazide compound.   Ar represents the following formula (3),

4. The polyimide resin according to claim 1, which is a tetravalent aromatic group derived from an aromatic tetracarboxylic acid anhydride represented by the formula:   R ₂ Is the following formula (10) or (11),

[Where R ₉ Independently represents a monovalent hydrocarbon group or alkoxy group having 1 to 6 carbon atoms, X represents CO, n ₁ Independently represents an integer of 0-4]
The polyimide resin according to claim 1, which is represented by: The following components (A) and (B),
(A) Structural units represented by the following general formulas (1) and (2):

[Wherein Ar is a tetravalent aromatic group derived from an aromatic tetracarboxylic acid anhydride, R ₁ is a divalent diaminosiloxane residue derived from diaminosiloxane, and R ₂ is derived from an aromatic diamine. Each represents a divalent aromatic diamine residue, Ar and / or R ₂ contains a ketone group, m and n represent the molar ratio of each constituent unit, and m is from 0.75 to 1.0. N is in the range of 0 to 0.25 . However, when n is 0, Ar contains the ketone group. ]
Having a weight average molecular weight of 10,000 to 200,000,
And (B) an amino compound having at least two primary amino groups as functional groups,
And the component (B) is contained so that the total amount of the primary amino group is within the range of 0.004 mol to 1.5 mol with respect to 1 mol of the ketone group in the component (A). Adhesive resin composition.   The adhesive resin composition according to claim 6, wherein in the general formula (2), n is at least 0.2. The adhesive resin composition according to claim 6 or 7 , wherein the amino compound is a dihydrazide compound.   Ar represents the following formula (3),

The adhesive resin composition according to any one of claims 6 to 8, which is a tetravalent aromatic group derived from an aromatic tetracarboxylic acid anhydride represented by the formula:   R ₂ Is the following formula (10) or (11),

[Where R ₉ Independently represents a monovalent hydrocarbon group or alkoxy group having 1 to 6 carbon atoms, X represents CO, n ₁ Independently represents an integer of 0-4]
The adhesive resin composition according to any one of claims 6 to 9, which is represented by: The hardened | cured material obtained by hardening | curing the adhesive agent resin composition of any one of Claim 6 to 10 . A cover lay film in which an adhesive layer and a cover lay film material layer are laminated,
The coverlay film, wherein the adhesive layer is formed using the adhesive resin composition according to any one of claims 6 to 10 . The circuit board provided with the base material, the wiring layer formed on this base material, and the coverlay film of Claim 12 which coat | covers this wiring layer. The circuit board according to claim 13 , wherein the peel strength between the wiring layer and the coverlay film after a long-term heat resistance test at 150 ° C. for 1000 hours in the air is 0.2 kN / m or more. Structural units represented by the following general formulas (1) and (2):

[Wherein Ar is a tetravalent aromatic group derived from an aromatic tetracarboxylic acid anhydride, R ₁ is a divalent diaminosiloxane residue derived from diaminosiloxane, and R ₂ is derived from an aromatic diamine. Each represents a divalent aromatic diamine residue, Ar and / or R ₂ contains a ketone group, m and n represent the molar ratio of each constituent unit, and m is from 0.75 to 1.0. N is in the range of 0 to 0.25. However, when n is 0, Ar contains the ketone group. ]
Preparing a polyimide solution containing polyimidesiloxane having a weight average molecular weight of 10,000 to 200,000 ,
In the polyimide solution, an amino compound having at least two primary amino groups as functional groups, and an amino compound having at least two primary amino groups as functional groups with respect to 1 mole of the ketone group in the polyimide siloxane. Adding the amino compound so that the total amino groups are within the range of 0.004 mol to 1.5 mol ,
A step of causing a condensation reaction between the ketone group of the polyimidesiloxane and the primary amino group of the amino compound;
A method for producing a polyimide resin comprising:   In the said General formula (2), n is at least 0.2, The manufacturing method of the polyimide resin of Claim 15. The method for producing a polyimide resin according to claim 15 or 16 , wherein the amino compound is a dihydrazide compound.   Ar represents the following formula (3),

The method for producing a polyimide resin according to any one of claims 15 to 17, which is a tetravalent aromatic group derived from an aromatic tetracarboxylic acid anhydride represented by:   R ₂ Is the following formula (10) or (11),

[Where R ₉ Independently represents a monovalent hydrocarbon group or alkoxy group having 1 to 6 carbon atoms, X represents CO, n ₁ Independently represents an integer of 0-4]
The method for producing a polyimide resin according to any one of claims 15 to 18, which is represented by: A circuit board manufacturing method comprising: a base material; a wiring layer formed on the base material; and a coverlay film that covers the wiring layer,
A coverlay film having an adhesive layer is prepared by applying and drying the adhesive resin composition according to any one of claims 6 to 10 on a coverlay film material layer in a solution state. Process,
Arranging the cover lay film so that the adhesive layer contacts the wiring layer, and thermocompression bonding,
Simultaneously with the thermocompression bonding, the ketone group of the (A) component and the primary amino group of the (B) component are subjected to a condensation reaction to form a C = N bond.