JP3031064B2 - Heat resistant adhesive - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a method for producing an epoxy compound comprising: (a) a soluble polyimide siloxane; (b) an epoxy / polyoxyalkylene-modified polysiloxane; (c) another epoxy compound having an epoxy group; and (d) an epoxy curing agent. The present invention relates to a heat-resistant adhesive characterized by being contained as a resin component at a specific composition ratio.

The heat-resistant adhesive of the present invention can bond various metal foils such as copper, aluminum and iron to heat-resistant supporting materials such as heat-resistant films and inorganic sheets at a relatively low temperature. In the laminate bonded with the above-mentioned heat-resistant adhesive, the adhesive layer shows a sufficient adhesive strength and also shows excellent heat resistance. For example, a flexible wiring board, TAB (Tape Automate) is used.
d Bonding) If used for the production of copper-clad substrates, etc., each substrate obtained by using the heat-resistant adhesive can perform various high-temperature processing steps such as soldering with confidence. The quality of the final product can be improved and the defect rate can be reduced.

[0003]

2. Description of the Related Art Conventionally, flexible wiring boards have often been manufactured by laminating an aromatic polyimide film and a copper foil using an adhesive such as an epoxy resin or a urethane resin. However, when the flexible wiring board manufactured using a known adhesive is exposed to a high temperature in a subsequent soldering process, there is a problem that the adhesive layer causes blistering or peeling, and the heat resistance of the adhesive is high. It has been desired to improve.

An imide resin-based adhesive has been proposed as a heat-resistant adhesive, for example, a precondensation comprising N, N '-(4,4'-diphenylmethane) bismaleimide and 4,4'-diaminodiphenylmethane. Things are known. However, since the precondensate itself is brittle, it is not suitable as an adhesive for a flexible wiring board.

[0005] As a method of improving the above disadvantage, for example,
JP-A-62-232475 and JP-A-62-23
No. 5382 discloses an adhesive film (dry film or bonding sheet) formed from a resin composition obtained by mixing an aromatic polyimide obtained from benzophenonetetracarboxylic acid and an aromatic diamine and polybismaleimide, and then forming the adhesive film. Is sandwiched between a heat-resistant film and a copper foil to perform thermocompression bonding.

However, the above-mentioned adhesive film has a softening point of 180 ° C. or higher, and can bond the heat-resistant film to the copper foil at a high temperature of about 260 to 280 ° C. and at a temperature of 30 to 60 kg / cm. ^It is necessary to carry out under a high pressure of about ^{2 and} under such bonding conditions, it is extremely difficult to continuously laminate the heat-resistant film and the copper foil using an organic resin pressure roll, This was problematic in terms of practicality.

On the other hand, as a coating composition for electronic parts such as wiring boards, a resin solution (varnish) in which an epoxy resin is blended with aromatic polyimide or the like is used as a heat-resistant coating layer made of the cured resin and a wiring board or the like. In order to improve the adhesiveness, various coating compositions have been proposed as known adhesives for bonding a copper foil and an aromatic polyimide film in the production of a copper-clad substrate as described above. Is the temperature of lamination or curing is high,
There is a problem that the compatibility between the aromatic polyimide and the epoxy resin or the compatibility between the aromatic polyimide and the solvent is low, or the adhesive layer after bonding and curing is not flexible. I couldn't do it.

[0008]

SUMMARY OF THE INVENTION An object of the present invention is to solve the problems of the above-mentioned known adhesives by applying an adhesive solution, drying, laminating a copper foil, and curing an adhesive layer. It is an object of the present invention to provide a heat-resistant adhesive exhibiting high adhesiveness at a high temperature and capable of suitably bonding a heat-resistant film and various metal foils through the following steps.

[0009] The inventors of the present invention have made it clear that (a) a specific soluble polyimide siloxane, (b) an epoxy / polyoxyalkylene-modified polysiloxane, (c) another epoxy compound having an epoxy group, and (d) an epoxy curing agent. When a resin component having a specific composition is used as an adhesive, a sea-island structure in which particles having a particle diameter of 0.1 to 5 μm are uniformly dispersed in a matrix resin of an adhesive layer after bonding and curing is exhibited. And found that it was an adhesive that could achieve the above object, and reached the present invention.

[0010]

[Means for Solving the Problems] The present invention provides (a)
3,3 ′, 4′-biphenyltetracarboxylic acid or 3,3 ′, 4,4′-biphenyltetracarboxylic acid, a dianhydride of the acid, or an ester of the acid
100 mol% and 3,3 ′, 4,4′-diphenylethertetracarboxylic acid, bis (3,4-dicarboxyphenyl) methane, 2,2-bis (3,4-dicarboxyphenyl) propane, An aromatic tetracarboxylic acid component comprising pyromellitic acid, a dianhydride of the acid, or an ester of the acid in an amount of 0 to 40 mol%;

[0010]

Embedded image

H ₂ N—R— [Si (R ₁ ) (R ₂ ) —O
-] N-Si (R ₃ ) (R ₄ ) -R-NH ₂ (I) (wherein R is a divalent hydrocarbon residue comprising a methylene group or a phenylene group having 2 to 6 carbon atoms) And R
₁ , R ₂ , R ₃ and R ₄ each represent a lower alkyl group having 1 to 5 carbon atoms or a phenyl group, and n is 3 to 60, preferably 5 to
Indicates an integer of 50. Diaminopolysiloxane 10-80 mol% represented by), and the general formula _{H 2 N-Bz-Bz-} NH 2 _{below, H 2 N-Bz-O} -Bz-
_{NH 2, H 2 N-Bz} -CO-Bz-NH 2, H 2 N-Bz-SO 2
_{-Bz-NH 2, H 2 N} -Bz-CH 2 -Bz-NH 2, H 2 N-Bz-C
_{(CH 3) 2 -Bz-NH} 2, H 2 N-Bz-C (CF 3) 2 -Bz-NH 2, H 2 N-Bz-O-Bz-O-Bz-NH 2, H 2 N- B
_{z-Bz-Bz-NH 2} , H 2 N-Bz-O-Bz-C 3 F 6 -Bz-O-Bz-NH
_{2, H 2 N-Bz-} O-Bz-C 3 H 6 -Bz-O-Bz-NH
_2, or _{H 2 N-Bz-O-} Bz-SO 2 -Bz-O-Bz-NH 2 ( however, Bz represents a benzene ring.) At least one 20 to 90 mole% of an aromatic diamine represented by 100 parts by weight of a soluble polyimide siloxane obtained from a diamine component comprising: (b) an epoxy-polyoxyalkylene-modified poly (polysiloxane) having at least one epoxy group and one polyoxyalkylene group at the terminal or side chain of the polysiloxane. 1 to 60 parts by weight of siloxane, (c) bisphenol A
Type epoxy resin, bisphenol F type epoxy resin, phenol novolak type epoxy resin, alkyl polyvalent phenol type epoxy resin, polyfunctional type epoxy resin, glycidyl ether type epoxy resin, glycidyl ester type epoxy resin, or glycidyl The present invention relates to a heat-resistant adhesive comprising 15 to 250 parts by weight of an epoxy compound having an epoxy group, which is an amine type epoxy resin, and (d) an epoxy curing agent as a resin component.

The aromatic tetracarboxylic acid component mainly composed of biphenyltetracarboxylic acids used in the present invention includes 3,3 ′, 4,4′-biphenyltetracarboxylic acid, 2,3,3 ′, 4 '-Biphenyltetracarboxylic acid, or a biphenyltetracarboxylic acid such as an acid dianhydride or esterified product thereof in an amount of 60 mol% or more,
Particularly, an aromatic tetracarboxylic acid component containing 80 to 100 mol% is used. Among them, in particular,
3 ′, 4′-biphenyltetracarboxylic dianhydride is
The polyimide siloxane is suitable because it has excellent solubility in an organic polar solvent, compatibility with an epoxy compound, and the like.

The aromatic tetracarboxylic acid component which can be used together with the biphenyltetracarboxylic acids used in the present invention includes, for example, 3,3 ′, 4,
4'-benzophenonetetracarboxylic acid, 3,3 ',
4,4′-diphenylethertetracarboxylic acid, bis (3,4-dicarboxyphenyl) methane, 2,2-bis (3,4-dicarboxyphenyl) propane, pyromellitic acid, or their acid dianhydrides, Preference is given to esterified products and the like. However, if the amount of these is too large, the polyimide siloxane becomes insoluble in an organic polar solvent or the compatibility with an epoxy resin deteriorates, which is not suitable.

In the present invention, as the diaminopolysiloxane represented by the general formula (1), R in the formula has 2 carbon atoms.
A divalent hydrocarbon residue consisting of a plurality of methylene groups or a phenylene group of up to 6, especially 3 to 5, R _{1 to} R ₄
Is preferably a lower alkyl group having 1 to 5 carbon atoms such as a methyl group, an ethyl group, or a propyl group, or a phenyl group,
Furthermore, it is preferable that n is especially about 5 to 20, and more preferably about 5 to 15. If the number of carbon atoms of R and R _{1 to} R ₄ is too large, the heat resistance is deteriorated. If the number of n is too large, the reactivity with the aromatic tetracarboxylic acid component is reduced, or the molecular weight of the obtained polyimide siloxane is reduced. The above-mentioned range is appropriate because the solubility is lowered, the solubility in an organic polar solvent is reduced, and the compatibility with other organic compounds is deteriorated.

Specific examples of the diaminopolysiloxane represented by the general formula (1) include ω, ω′-bis (2-aminoethyl) polydimethylsiloxane and ω, ω′-bis (3
-Aminopropyl) polydimethylsiloxane, ω, ω '
-Bis (4-aminophenyl) polydimethylsiloxane, ω, ω'-bis (4-amino-3-methylphenyl) polydimethylsiloxane, ω, ω'-bis (3-aminopropyl) polydiphenylsiloxane, and the like. be able to.

The aromatic diamine used together with the diaminopolysiloxane is generally an aromatic diamine compound having two or more, especially 2 to 5, aromatic rings such as a benzene ring, for example, a biphenyl-based diamine compound and a diphenyl ether. Diamine compound, benzophenone diamine compound, diphenylsulfone diamine compound, diphenylmethane diamine compound, diphenylpropane diamine compound, 2,2-bis (phenyl) hexafluoropropane diamine compound, diphenylene sulfone diamine compound, di ( Phenoxy) benzene-based diamine compound, di (phenyl) benzene-based diamine compound, bis (phenoxyphenyl) sulfone-based diamine compound, bis (phenoxyphenyl) hexafluoropropane-based diamine compound , It can be exemplified bis (phenoxyphenyl) propane based diamine compounds, they alone or can be used as a mixture.

Specific examples of the aromatic diamine include 1,4
Diamine diphenyl compounds such as diaminodiphenyl ether and 1,3-diaminodiphenyl ether, 1,3-di (4-diaminophenoxy) benzene,
Di (phenoxy) benzene based diamine compound such as 1,4-bis (4-aminophenoxy) benzene, 2,2-bis [4- (4-aminophenoxy) phenyl] propane, 2,2-bis [4- ( Bis (phenoxyphenyl) propane-based diamine compounds such as 3-aminophenoxy) phenyl] propane, di [bis (4- (4-aminophenoxy) phenyl] sulfone, and di [bis (4- (3-aminophenoxy) phenyl] sulfone) Aromatic ring such as (phenoxyphenyl) sulfone diamine compound
Preferred are aromatic diamine compounds having up to 5 aromatic diamine compounds.

In the present invention, the diaminopolysiloxane and the aromatic diamine are preferably 10 to 80 mol%, preferably 15 to 70 mol%, more preferably 20 to 60 mol%, and the latter 20 to 90 mol%. Is 30-85
Mol%, more preferably 40 to 80 mol%. If either component is too large or too small to fall outside these ranges, the solubility of the polyimidesiloxane in the organic polar solvent will decrease, the compatibility with other organic compounds will deteriorate, and the elastic modulus will decrease. Not suitable because it will be too expensive.

In the present invention, the polyimide siloxane (a) is produced by the following method. (A ₁₎ an aromatic tetracarboxylic acid component and a diaminopolysiloxane and diamine component aromatic diamines, continuously and substantially equimolar used in an organic polar solvent temperature 15 to 2
A method of obtaining polyimide siloxane by polymerization and imidization at 50 ° C.

(A ₂ ) The diamine component is separated, and an excess amount of the aromatic tetracarboxylic acid component and diaminopolysiloxane are polymerized and imidized in an organic polar solvent at a temperature of 15 to 250 ° C. to obtain an average degree of polymerization. An imidosiloxane oligomer having an acid or acid anhydride group at about 1 to 10 terminals is prepared. Separately, an aromatic tetracarboxylic acid component and an excess amount of an aromatic diamine are mixed in an organic polar solvent at a temperature of 15 to 250.
C. to polymerize and imidize at an average degree of polymerization of 1 to 10 to prepare an imide oligomer having an amino group at a terminal,
Then, the two are mixed so that the acid component and the diamine component are substantially equimolar, and reacted at a temperature of 15 to 60 ° C., and the temperature is further increased to 130 to 250 ° C. to obtain a block type polyimide siloxane. Method.

(A ₃ ) An aromatic tetracarboxylic acid component, a diaminopolysiloxane component and an aromatic diamine component are used in approximately equimolar amounts, and are first heated to a temperature of 20 to 80 in an organic polar solvent.
There is a method in which a polyamic acid is once obtained by polymerization at a temperature of ° C. and then imidized to obtain a polyimide siloxane.

The organic polar solvent used in the production of polyimidesiloxane in the present invention includes, for example, N, N-dimethylacetamide, N, N-diethylacetamide,
Contains amide solvents such as N, N-dimethylformamide, N, N-diethylformamide, N-methyl-2-pyrrolidone, and sulfur atoms such as dimethylsulfoxide, diethylsulfoxide, dimethylsulfone, diethylsulfone, and hexamethylsulfonamide. Solvent, cresol,
Examples thereof include phenol solvents such as phenol and xylenol, solvents having an oxygen atom in the molecule such as acetone, methanol, ethanol, ethylene glycol, dioxane and tetrahydrofuran, and other solvents such as pyridine and tetramethylurea. Further, if necessary, other types of organic solvents such as aromatic hydrocarbon solvents such as benzene, toluene and xylene, and solvent naphtha and benzonitrile can be used in combination.

In the present invention, as the polyimide siloxane, those obtained by any of the above methods (a ₁ ) to (a ₃ ) may be used. What can be dissolved at a high concentration of at least 3% by weight or more, especially about 5 to 40% by weight is preferable since an adhesive having good bonding operation and bonding performance can be obtained.

The imidation ratio of the polyimide siloxane is as follows:
The imidation ratio is 9 as measured by infrared absorption spectrum analysis.
0% or more, especially 95% or more is preferred. In the infrared absorption spectrum analysis, a high imidization ratio is obtained such that substantially no absorption peak relating to the amide-acid bond of the polymer is found and only the absorption peak relating to the imide ring bond is observed. Preferably, there is.

The logarithmic viscosity of the polyimidesiloxane (measured concentration: 0.5 g / 100 ml solvent, solvent: N-methyl-2-pyrrolidone, measurement temperature: 30 ° C., viscometer: Cannon-Fenske viscometer) is 0.05. To 4, more preferably about 0.1 to 3.

Further, when the above-mentioned polyimidesiloxane is molded into a film, its elastic modulus is 250 kg / m.
m ² or less, especially 0.5 to 200 kg / mm ² ,
Thermal decomposition initiation temperature is 250 ° C. or higher, particularly 300 ° C. or higher, and secondary rearrangement temperature is −10 ° C. or higher, particularly 10 to 250 ° C.
It is preferable to achieve the object of the present invention.

The amount of the epoxy / polyoxyalkylene-modified polysiloxane (b) used in the present invention is 1 to 100 parts by weight of the polyimide siloxane.
60 parts by weight, preferably 1.5 to 15 parts by weight. If the amount is too large or too small, the compatibility with other components is poor and a uniform solution is not obtained, and the effect is not exhibited. Therefore, the above range is appropriate.

The epoxy / polyoxyalkylene-modified polysiloxane used in the present invention includes a reactive polysiloxane oil having a hydroxyl group, a carboxyl group, or an amino group at a terminal, a bisphenol type epoxy resin, a phenol novolak type epoxy resin, Glycidyl ether type epoxy resin, epoxy compound such as glycidyl ester type epoxy resin and polyoxypropylene, obtained by reacting with a polyoxyalkylene compound such as polyoxyethylene at a temperature of about 80 to 140 ° C. Any epoxy-polyoxyalkylene-modified polysiloxane having at least one epoxy group therein and further having at least one polyoxyalkylene group may be used.

As the epoxy / polyoxyalkylene-modified polysiloxane, those having a melting point of 90 ° C. or less or those which are liquid at 30 ° C. or less are preferred. Further, the epoxy / polyoxyalkylene-modified siloxane compound preferably has at least one epoxy group and further has at least one polyoxyalkylene group. For example, the epoxy / polyoxyalkylene-modified silicone oil ( Toray Dow Corning Silicone Co., Ltd., SF-8421EG, BY-16-845,
BY-16-876 etc.).

The proportion of the other epoxy compound (c) having an epoxy group used in the present invention is from 1 to 250 parts by weight, preferably from 20 to 150 parts by weight, based on 100 parts by weight of the polyimide siloxane. If it is too small or too small, the uncured adhesive becomes sticky and lacks flexibility after curing, and the softening point of the uncured adhesive is too high, and the adhesive properties after curing deteriorates. It is desirable.

Other epoxy compounds having an epoxy group used in the present invention include epoxy compounds having one or more epoxy groups, for example, bisphenol A
Or bisphenol F type epoxy resin (manufactured by Yuka Shell Co., Ltd., trade names: Epikote 807, Epikote 82)
8), phenol novolak type epoxy resin, alkyl polyphenol type epoxy resin (manufactured by Nippon Kayaku Co., Ltd., RE701, RE550S, etc.), polyfunctional epoxy resin (manufactured by Sumitomo Chemical Co., Ltd., ELM-100, etc.), glycidyl Ether type epoxy resin, glycidyl ester type epoxy resin, glycidyl amine type epoxy resin (manufactured by Mitsubishi Gas Chemical Co., Ltd., trade name: Tetrad X, etc.) or the like can be used alone or in combination. If the melting point of the epoxy compound is too high, the softening point of the uncured adhesive increases, so that the melting point is 90 ° C. or less, especially about 0 to 80 ° C., or the liquid is a temperature of 30 ° C. or less. Is preferred.

The epoxy curing agent (d) used in the present invention includes known curing agents such as imidazoles, tertiary amines, triphenylphosphines, dicyandiamides, hydrazines, and fragrances. Examples thereof include aromatic diamines, phenol novolak type curing agents having a hydroxyl group, and organic peroxides, and these can be used together with known curing accelerators.

The epoxy curing agent used in the present invention is used in an amount of 0.01 to 110 parts by weight based on 100 parts by weight of the epoxy compound.

The heat-resistant adhesive of the present invention comprises the above-mentioned polyimide siloxane (a), epoxy-polyoxyalkylene-modified polysiloxane compound (b), another epoxy compound having an epoxy group (c), and an epoxy curing agent ( d)
Can be easily obtained by uniformly stirring and mixing a predetermined amount of When mixing, it can be mixed in a suitable organic polar solvent to obtain a solution composition of a heat-resistant adhesive. As the organic polar solvent, an organic polar solvent that can be used for obtaining the polyimide siloxane, for example, a solvent having an oxygen atom in a molecule such as dioxane or tetrahydrofuran or an amide-based solvent such as N-methyl-2-pyrrolidone is preferably used. Is done.

The concentration of the solution composition is suitably from 3 to 50% by weight, preferably from 5 to 40% by weight.
C) is from 0.1 to 10,000 poise, especially from 0.2 to 50 poise.
It is preferably about 00 poise, more preferably about 0.3 to 1000 poise.

The heat-resistant adhesive of the present invention has a softening point (temperature at which softening starts on a hot plate) of the composition containing only the uncured resin component of 150 ° C. or lower, particularly 140 ° C. or lower, and more preferably 0 ° C. or lower. It is preferable that it is about 130 degreeC.

The heat-resistant adhesive of the present invention is obtained by preparing a solution composition of the heat-resistant adhesive in which all of the above-mentioned resin components are dissolved in an organic polar solvent, by using a suitable metal foil, aromatic polyimide film, aromatic polyester. Or the like, or a film surface of a thermoplastic resin such as polyethylene, and apply the applied layer at a temperature of 80 to 200 ° C. for 20 seconds to 1 hour.
By drying for 00 minutes, the uncured heat-resistant adhesive thin film (thickness: substantially less than 1% by weight of the solvent, preferably less than 0.5% by weight of the residual solvent). About 1-200 μm).

The uncured heat-resistant adhesive thin film produced as described above has a suitable flexibility, and is wound around a paper tube or the like, or is punched by a punching method or the like. It is also possible to further laminate a laminated sheet in which a thin layer of an uncured heat-resistant adhesive is formed on the heat-resistant or thermoplastic film and a metal foil or a heat-resistant film for transfer destination. Then, by passing between a pair of rolls (lamination rolls) heated to a temperature of about 20 to 200 ° C., a sheet layer of a heat-resistant adhesive may be transferred onto a metal foil or a heat-resistant film for a transfer destination. It is possible.

In order to form a laminate such as a copper-clad substrate by bonding a heat-resistant film and a metal foil or the like using the heat-resistant adhesive of the present invention, for example, a thin film formed as described above is used. Through the heat-resistant adhesive layer of the heat-resistant film and the metal foil at a temperature of 80 ~ 200 ℃, especially 120 ~ 180 ℃,
The laminate is laminated under pressure (0.2 to 8 kg / cm ² ), and the laminated product is heated at a temperature of about 140 to 250 ° C., particularly 150 to 230 ° C. for 3 hours.
By heating and curing the heat-resistant adhesive layer by heating for 0 minute to 40 hours, particularly 1 to 30 hours, the laminate can be easily and continuously manufactured without any trouble.

The heat-resistant adhesive of the present invention is bonded to a heat-resistant film such as an aromatic polyimide film, a polyamide film, a polyetheretherketone film or a polyethersulfone film and a suitable metal foil such as copper, aluminum or iron. It can be suitably used for
Further, the heat-resistant adhesive of the present invention may contain a small proportion of other thermosetting resin such as bismaleimide resin as a resin component.

Using the heat-resistant adhesive of the present invention,
When the section of the adhesive layer after curing is observed with a transmission electron microscope (FIG. 1), dispersed particles having a particle size of 0.1 to 5 μm are formed as independent particles in the matrix resin of the adhesive layer. It is observed that the adhesive layer has a sea-island structure. If the particle size of the dispersed particles is larger than 5 μm, the bonding surface becomes non-uniform, so that the strength of the adhesive layer is weakened, which is not preferable. By adopting such a sea-island structure after bonding and curing, it has excellent characteristics of balance between heat resistance and flexibility, and also contributes to stability of adhesion. Such a form tends to change the failure mode to cohesive failure in the peel test, and the adhesive strength is stabilized.

[0042]

The present invention will be described below in further detail with reference to examples. In the following examples, logarithmic viscosities (η
_inh ) is a solution prepared by uniformly dissolving polyimide siloxane in N-methyl-2-pyrrolidone so that the concentration becomes 0.5 g / 100 ml of a solvent, and the solution is prepared using a Cannon-Fenske viscometer. And the viscosity of the solvent were measured at 30 ° C., and the values were calculated from the following formula.

[0043]

(Equation 1)

The softening temperature of the polyimide siloxane film is a value obtained by measuring the tan δ (high temperature side) of a viscoelastic peak in a viscoelasticity test using a mechanical spectrometer: RDS-2 manufactured by Rheometrics.

The modulus of elasticity of the polyimide siloxane film was measured using a tensile tester manufactured by Intesco Co., Ltd.
It is a result measured under the condition of mm / min.

The workability of the adhesive is as follows: in the process of forming various laminates using a heat-resistant adhesive, tackiness (adhesion with a protective film), punching property of the laminate, and heat bonding. Is a comprehensive evaluation of the workability of
◎ indicates excellent, indicates good, △ indicates normal, and × indicates poor.

The adhesive strength was measured using a tensile tester manufactured by Intesco Corporation at a peeling rate of 50 mm / min and a measurement temperature of 25 ° C.
At a measurement temperature of 180 ° C. and a 180 ° peel test at a measurement temperature of 180 ° C.

A copper-clad substrate is formed using a heat-resistant adhesive, and the radius of curvature indicating the curl resistance of the wiring board after the copper foil is removed by etching is JIS standard C5012.
[Radius of curvature (mm) = L ² / 8h
(L: length of sample, h: height of sled)].

[Production of Imidosiloxane Oligomer] Reference Example 1 2, 3, 3 ', 4' was placed in a 500 ml glass flask equipped with a thermometer, a charging / discharging port, and a stirrer.
-Biphenyltetracarboxylic dianhydride (a-BPD
A) 0.054 mol, ω, ω′-bis (3-aminopropyl) polydimethylsiloxane (manufactured by Shin-Etsu Silicon Co., Ltd., X-22-161AS, n: 9) 0.027 mol,
And 160 g of N-methyl-2-pyrrolidone (NMP) were added, the temperature was raised to 50 ° C. in a stream of nitrogen, and the mixture was stirred at this temperature for 2 hours to form an amic acid oligomer. Temperature, and at that temperature
After stirring for an hour, an imide siloxane oligomer having an anhydride group at the terminal (A-1 component, average degree of polymerization: 1) was produced.

Reference Examples 2 to 3 The amounts of a-BPDA and diaminopolysiloxane [X-22-161AS, manufactured by Shin-Etsu Silicon Co., Ltd.]
n: 9) and an imide siloxane oligomer having an anhydride group at the terminal (A-2, average degree of polymerization: 2 and A-3, average degree of polymerization: 6) in the same manner as in Reference Example 1 except that NMP was used. Was manufactured respectively.

[Production of imide oligomer] Reference Example 4 The amount of a-BPDA, 2,3,3 ', 4'-
Bis [4- (4-aminophenoxy) phenyl] propane (BAPP) and NMP were charged in the same manner as in Reference Example 1 and stirred at 50 ° C. for 2 hours in a nitrogen stream to produce an amic acid oligomer. Reaction solution 200
C., and stirred at that temperature for 3 hours to obtain an imide oligomer B-1 having an amino group at the terminal (average degree of polymerization: 1).
Was generated.

Reference Examples 5 to 7 In the same manner as in Reference Example 4, except that a-BPDA, BAPP and NMP shown in Table 1 were used, imide oligomer B-2 having an amino group at the terminal (average degree of polymerization) :
2), B-3 (average degree of polymerization: 5), and B-4 (average degree of polymerization: 10) were produced.

[0053]

[Table 1]

[Production of Polyimide Siloxane] Reference Example 8 The imide siloxane oligomer (A-
3) 0.0025 mol of 20 wt% NMP solution and 0.002 of imide oligomer (B-4) produced in Reference Example 7
5 mol of a 20% by weight NMP solution was charged into a glass flask having a capacity of 500 ml, and heated in a nitrogen stream and stirred at 50 ° C. for 1 hour to produce a polyamic acid block polymer in the same manner as in Reference Example 1. Then, the mixture was heated and stirred at 200 ° C. for 3 hours to produce a polyimidesiloxane (block polymer). This polyimide siloxane had an imidization ratio of 95% or more and an intrinsic viscosity of 0.45.

Reference Examples 9 to 11 Reference Examples 8 to 9 were conducted except that the oligomers prepared in the above Reference Examples 1 to 7 were used in the amounts and reaction conditions shown in Table 2.
In the same manner as in the above, polyimide siloxane (block polymer) was produced. Table 2 shows the logarithmic viscosities of each of the produced polyimide siloxanes, the elastic modulus when molded into a film, and the softening temperature.

REFERENCE EXAMPLE 12 a-B was placed in a glass flask having a capacity of 500 ml.
0.048 mol of PDA, diaminopolysiloxane [X-22-161AS, n: 9, manufactured by Shin-Etsu Silicon Co., Ltd.]
0.016 mol, BAPP 0.032 mol and NMP1
After charging 65 g, 5 g in a nitrogen stream as in Reference Example 1.
The mixture was stirred at 0 ° C. for 2 hours to form a polyamic acid oligomer, and then the reaction solution was heated to 200 ° C. and stirred for 3 hours to form a polyimide siloxane (random polymer). Table 2 shows the physical properties of these polyimide siloxanes.

[0057]

[Table 2]

Example 1 [Preparation of solution composition of heat-resistant adhesive] In a 500-ml glass flask, the polyimidesiloxane (block polymer, A-3
-B-4) 50 g, epoxy polyoxyalkylene-modified polysiloxane [SF-8421EG, manufactured by Dow Corning Toray Silicone Co., Ltd.], epoxy resin [Epicoat 807, manufactured by Yuka Shell Epoxy Co., Ltd.] 3
0 g, 20 g of a phenol novolak type curing agent (H-1 manufactured by Meiwa Kasei Co., Ltd.) and 0.1 parts of an imidazole curing agent
g and 185 g of dioxane at room temperature (25 ° C.)
For about 2 hours to prepare a uniform heat-resistant adhesive solution composition (viscosity at 25 ° C .: 7 poise). This solution composition maintained a uniform solution state even when left at room temperature for one week.

[Production of Laminate Using Heat-Resistant Adhesive] A solution of the above-mentioned heat-resistant adhesive was applied to a polyimide film (trade name: UPILEX-S, manufactured by Ube Industries, Ltd., thickness: 7).
5 μm) with a doctor blade to a thickness of 125 μm, then apply the applied layer at 50 ° C. for 30 minutes to 100 μm.
After drying by heating at 30 ° C. for 30 minutes, a heat-resistant adhesive layer (uncured dried layer, softening temperature: 50 ° C.) having a thickness of about 25 μm was formed on the polyimide film.

The polyimide film having the heat-resistant adhesive layer and the one-sided roughened copper foil (35 μm) are superposed,
The laminate was pressure-bonded by passing the laminate between rolls heated to 130 ° C. while applying pressure, and the pressed laminate was heated at 100 ° C. for 1 hour, 120 ° C. for 1 hour, and 160 ° C. for 1 hour.
Heat treatment was performed for 0 hour to cure the heat-resistant adhesive layer, thereby producing a laminate. The adhesive strength of the obtained laminate was measured, and the results are shown in Table 3.

Examples 2 to 6 Polyimide siloxanes (block polymers) produced in Reference Examples 9 to 11 as shown in Table 3 were used, and the composition of each component was changed as shown in Table 3. In the same manner as in Example 1, a solution composition of the heat-resistant adhesive was prepared. Example 1 was repeated except that the above solution compositions were used.
In the same manner as in, laminates were respectively manufactured. Table 3 shows the performance of the laminate.

Example 7 A heat-resistant adhesive was prepared in the same manner as in Example 1 except that the polyimidesiloxane (random polymer) produced in Reference Example 12 was used and the composition of each component was as shown in Table 3. The solution compositions of the agents were respectively adjusted. Laminates were produced in the same manner as in Example 1 except that each of the above solution compositions was used. Table 3 shows the performance of the laminate. An electron micrograph of the adhesive layer is shown in FIG. 1 (× 9000). Each example was the same as FIG.

[0063]

[Table 3]

Comparative Example 1 80 g of the polyimidesiloxane prepared in Reference Example 8 and an epoxy / polyoxyalkylene-modified polysiloxane [FS-842, manufactured by Dow Corning Toray Silicone Co., Ltd.]
1EG], 1 g of bisphenol A type epoxy resin [Epicoat 828, manufactured by Yuka Shell Co., Ltd.], 1 g of phenol novolak (H-1 manufactured by Meiwa Kasei Co., Ltd.)
A solution composition of a heat-resistant adhesive was prepared in the same manner as in Example 1 except that only 7 g and 230 g of dioxane were used. Except that the solution composition was used, the solution composition was applied on a polyimide film and dried in the same manner as in Example 1 to obtain an adhesive layer (uncured dried adhesive layer, thickness:
20 μm).

The adhesive layer formed on the above-mentioned polyimide film has poor tackiness and is easily peeled off from the polyimide film, and it is substantially impossible to manufacture a laminate by laminating with a copper foil. Was. Table 3 shows the results.

Comparative Example 2 The polyimide siloxane 50 produced in the above-mentioned Reference Example 9
g, epoxy resin [Eicoat 8 manufactured by Yuka Shell Co., Ltd.]
07] 20 g, polyfunctional epoxy resin [Sumitomo Chemical Co., Ltd.
Except that only 8 g of ELM-100 and 150 g of dioxane were used to prepare a solution composition of a heat-resistant adhesive. Except for using the solution composition, the solution composition was applied on a polyimide film and dried in the same manner as in Example 1 to obtain an adhesive layer (uncured dried adhesive layer, thickness: 20 μm). ) Formed. A laminate was manufactured in the same manner as in Example 1, except that the polyimide film having the adhesive layer was used. The results of the performance test of the laminate are shown in Table 3, where the radius of curvature of the etched film was 30 mm and the curl was extremely large.

In the column of "Type of epoxy / polyoxyalkylene-modified polysiloxane" in Table 3, "SF-
8421EG "," BY-16-845 "," BY-1
6-876 "represents an epoxy polyoxyalkylene-modified polysiloxane manufactured by Dow Corning Toray Silicone Co., Ltd. In the column of" Types of other epoxy compounds "in Table 3," Epicoat 807 " And "Epicoat 828" represent a bisphenol A type or bisphenol F type epoxy resin manufactured by Yuka Shell Co., Ltd.
"RE701" indicates an alkyl polyhydric phenol type epoxy resin manufactured by Nippon Kayaku Co., Ltd., "ELM-100" indicates a polyfunctional epoxy resin manufactured by Sumitomo Chemical Co., Ltd., and "Tetrad X" indicates Mitsubishi. The glycidylamine type epoxy resin manufactured by Gas Chemical Co., Ltd. is shown. Similarly, in the column of "Type of epoxy curing agent" in Table 3, "H-1" and "H-
5 "indicates a phenol novolak type curing agent manufactured by Meiwa Kasei Co., Ltd.

[0068]

According to the heat-resistant adhesive of the present invention, an uncured and thin heat-resistant adhesive layer can be easily formed by applying the solution composition on a support film and drying at a relatively low temperature. And the thin heat-resistant adhesive layer has sufficient flexibility, and the thin heat-resistant adhesive layer on the support film is subjected to perforation processing. There is no problem at all, and it is also possible to transfer onto another heat-resistant support film at an appropriate temperature, and to laminate the heat-resistant film and the copper foil at a relatively low temperature. Workability is good.

Furthermore, the heat-resistant adhesive of the present invention has excellent heat resistance, flexibility and the like even after being heat-cured to form a laminate, and has excellent properties after etching a copper foil or the like. Since the curl of the etching film is small, it can be suitably used particularly as an adhesive for a flexible wiring board, a copper-clad board for TAB, and the like.

[Brief description of the drawings]

FIG. 1 is a transmission electron micrograph showing a particle structure of an adhesive layer according to an example of the present invention.

Continuation of front page (72) Inventor Kenji Sonoyama 3-10 Nakamiyakitamachi, Hirakata-shi, Osaka Ube Industries, Ltd. Examiner at the Hirakata Research Laboratory Tatsuya Ando (56) References JP-A-5-25453 (JP, A) JP-A-60-130666 (JP, A) JP-A-2-158681 (JP, A) JP-A-1-121325 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) C09J 1 / 00-201/10 CA (STN) REGISTRY (STN)

Claims (1)

(57) [Claims] (A) 2,3,3 ', 4'-biphenyltetracarboxylic acid or 3,3', 4,4'-biphenyltetracarboxylic acid, a dianhydride of the acid, or an ester of the acid 60 to 100 mol% and 3,3 ', 4
4'-diphenylethertetracarboxylic acid, bis (3,4-dicarboxyphenyl) methane, 2,2-bis (3,4-dicarboxyphenyl) propane, pyromellitic acid, dianhydrides of these acids, Alternatively the aromatic tetracarboxylic acid component consisting of ester 0-40 mol%, their acids, formula _{I H 2 n-R- [Si} (R 1) (R 2) -O-] n-Si (R
₃ ) (R ₄ ) —R—NH ₂ (I) (wherein R represents a divalent hydrocarbon residue comprising a methylene group or a phenylene group having 2 to 6 carbon atoms;
₁ , R ₂ , R ₃ and R ₄ each represent a lower alkyl group having 1 to 5 carbon atoms or a phenyl group, and n represents an integer of 3 to 60. )
10 to 80 mol% of the following general formula: H ₂ N—Bz—Bz—NH ₂ , H ₂ N—Bz—O—Bz—
_{NH 2, H 2 N-Bz} -CO-Bz-NH 2, H 2 N-Bz-SO 2
_{-Bz-NH 2, H 2 N} -Bz-CH 2 -Bz-NH 2, H 2 N-Bz-C
_{(CH 3) 2 -Bz-NH} 2, H 2 N-Bz-C (CF 3) 2 -Bz-NH 2, H 2 N-Bz-O-Bz-O-Bz-NH 2, H 2 N- B
_{z-Bz-Bz-NH 2} , H 2 N-Bz-O-Bz-C 3 F 6 -Bz-O-Bz-NH
_{2, H 2 N-Bz-} O-Bz-C 3 H 6 -Bz-O-Bz-NH
_2, or _{H 2 N-Bz-O-} Bz-SO 2 -Bz-O-Bz-NH 2 ( however, Bz represents a benzene ring.) At least one 20 to 90 mole% of an aromatic diamine represented by (B) an epoxy / polyoxyalkylene-modified poly having at least one epoxy group and one polyoxyalkylene group at the terminal or in the side chain of the polysiloxane. Siloxane 1
60 parts by weight, (c) bisphenol A type epoxy resin, bisphenol F type epoxy resin, phenol novolak type epoxy resin, alkyl polyvalent phenol type epoxy resin, polyfunctional type epoxy resin, glycidyl ether type An epoxy resin, a glycidyl ester type epoxy resin, or 15 to 250 parts by weight of an epoxy compound having an epoxy group which is a glycidylamine type epoxy resin, and (d) an epoxy curing agent, which is contained as a resin component. Heat resistant adhesive.