JPH08193139A - Prepreg for printed wiring board and metal-clad laminate using the same - Google Patents

Abstract

PURPOSE: To prepare a prepreg for a printed wiring board which can be thermally press-bonded at a temp. of 200 deg.C or below and has excellent heat resistance, dielectric properties and dimensional stability by impregnating a substrate with a compsn. comprising a particular polyimide resin and a thermosetting resin. CONSTITUTION: A prepreg for a printed wiring board, comprising a substrate impregnated with a compsn. comprising a straight-chain polyimide resin and a thermosetting resin. The prepreg is prepared by a dry coating system using a solvent. The content ratio of the resin compsn. to the substrate in the prepreg is pref. (30:70) to (80:20). The glass transition temp. of the straight-chain polyimide resin, when it, together with the thermosetting resin, constitutes the resin compsn., is pref. in the range of from 60 to 170 deg.C. Particularly pref., the polyimide resin is a silicone-modified polyimide resin, and the thermosetting resin is an epoxy resin. The substrate is made of pref. a glass fiber or an aramid fiber.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention can be pressure-hardened at low temperature,
The present invention also relates to a prepreg having excellent heat resistance, dielectric properties, and dimensional stability, and a metal-clad laminate for a printed wiring board obtained by thermocompression bonding the prepreg with a metal foil.

[0002]

2. Description of the Related Art As a printed wiring board, a board made of paper-phenol resin, glass fiber-epoxy resin, or a polyimide film, a polyethylene terephthalate film or the like and a metal foil bonded to each other have been conventionally used.

Various prepregs or adhesive films are used in the process of laminating printed wiring boards to prepare a multilayer wiring board or compounding different kinds of circuit materials. In the field of such prepregs and metal-clad laminates for printed circuit boards, substrates in which paper is impregnated with phenolic resin, and substrates in which textiles such as glass fiber are impregnated with epoxy-based or bismaleimide-based resin have been used. .

However, although the phenol-based or epoxy-based prepreg has excellent adhesiveness, it has insufficient heat resistance, and the resin exudes greatly during thermocompression bonding, resulting in poor dimensional stability. In addition, although the bismaleimide-based prepreg has excellent heat resistance, it is insufficient in flexibility and poor in filling in irregularities on the circuit surface.

On the other hand, as a means for solving these various problems, a polyimide prepreg has recently been proposed. For example, a prepreg using a thermoplastic polyimide resin disclosed in JP-A-4-252234 is known. However, such a polyimide requires a thermocompression bonding temperature of 200 ° C. or higher in order to bond base materials such as copper or a polyimide film with a sufficient adhesive strength, and therefore, circuit oxidation is likely to occur, which is not preferable. At the same time, there are difficulties in terms of practicality such as equipment and workability.

Further, in order to perform thermocompression bonding at a low temperature, an adhesive film made of a polyimide resin having a silicone unit and an epoxy resin has been proposed (JP-A-6-
2002216). However, although such a film satisfies the circuit filling property and heat resistance, the dimensional stability of the resin alone is insufficient, and there is a problem that waviness, warpage, etc. easily occur in the production of a multilayer wiring board. was there.

[0007]

DISCLOSURE OF THE INVENTION The present invention can be obtained by thermocompression bonding a prepreg which can be bonded under thermocompression bonding conditions of 200 ° C. or less and which is excellent in heat resistance, dielectric properties and dimensional stability, and a metal foil. An object is to provide a metal-clad laminate.

[0008]

That is, the present invention provides a prepreg for a printed wiring board obtained by impregnating a substrate with a resin composition comprising a linear polyimide resin and a thermosetting resin, and a prepreg for the metal foil. It is a metal-clad laminate obtained by thermocompression bonding.

The linear polyimide resin of the present invention may be any polyimide resin obtained from an aromatic tetracarboxylic acid and a diamine, but is preferably a glass when used as a resin composition with a thermosetting resin. Transition point is 60-1
It is a polyimide resin in the range of 70 ° C. A resin composition having a glass transition point of higher than 170 ° C. has insufficient fluidity under thermocompression bonding conditions of 200 ° C. or lower, and therefore does not sufficiently fill irregularities on a circuit surface, while having a temperature of less than 60 ° C. , The adhesiveness is good, but the heat resistance and chemical resistance are inferior, which is not preferable.

A particularly preferable polyimide resin from the above viewpoint is a silicone-modified polyimide resin having a silicone unit. As the silicone-modified polyimide resin, the following general formula (1)

Embedded image (However, in the formula, Ar ₁ represents a tetravalent aromatic group, R ₁ and R ₂ represent a divalent hydrocarbon group, and R _{3 to} R ₆ represent a hydrocarbon group having 1 to ₆ carbon atoms. , N represents an integer of 1 to 20) and the following general formula (2)

Embedded image (However, in the formula, Ar ₁ represents a tetravalent aromatic group, and Ar ₂
Is a polyimide resin having a repeating unit represented by a divalent aromatic group).

The polyimide resin having the repeating units represented by the above general formulas (1) and (2) can be obtained by reacting diaminosiloxane and aromatic diamine with tetracarboxylic dianhydride.

Specific examples of the tetracarboxylic acid dianhydride include 3,3 ', 4,4'-diphenyl ether tetracarboxylic acid dianhydride and 3,3', 4,4'-diphenylsulfone tetracarboxylic acid dianhydride. Things, 3,3 ', 4,4'
-Benzophenone tetracarboxylic dianhydride, 2,
The 2 ', 2,3'-benzophenone tetracarboxylic dianhydride is raised. In addition, as a part of the tetracarboxylic dianhydride component, 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride, 2,3,3 ′, 4′-biphenyltetracarboxylic dianhydride, Pyromellitic dianhydride,
1,4,5,8-naphthalenetetracarboxylic dianhydride, 1,4,5,6-naphthalenetetracarboxylic dianhydride, 3,4,9,10-perylenetetracarboxylic dianhydride, 3, 3,6,7-anthracene tetracarboxylic acid dianhydride, 1,2,7,8-phenanthrene tetracarboxylic acid dianhydride, 4,4 ′-(hexafluoroisopropylidene) phthalic acid dianhydride, etc. To be

The diaminosiloxane is represented by the following general formula (3)

Embedded image (However, in the formula, R ₁ and R ₂ represent a divalent hydrocarbon group, R _{3 to} R ₆ represent a hydrocarbon group having 1 to ₆ carbon atoms, and n
Represents an integer of 1 to 20) is used. As a specific example, preferably

[Chemical 4] Etc.

The average n number of these diaminosiloxanes is preferably in the range of 1-20, more preferably 5-15. By introducing a silicon unit into a polyimide resin by using these diaminosiloxanes, it is possible to impart fluidity at the time of thermocompression bonding and improve the filling property into the irregularities on the printed circuit board surface.

Specific examples of the aromatic diamine include
m-phenylenediamine, p-phenylenediamine,
4,4'-diaminodiphenylpropane, 4,4'-diaminodiphenylmethane, benzidine, 4,4'-diaminodiphenyl sulfide, 4,4'-diaminodiphenyl sulfone, 3,3'-diaminodiphenyl sulfone, 4,4 ' -Diaminodiphenyl ether, 3,3 '
-Diaminodiphenyl ether, 4,4'-diamino-
Examples thereof include p-terphenyl, but for the purpose of improving solubility in organic solvents, 2,2-bis (3-aminophenoxyphenyl) propane, 2,2-bis (4-aminophenoxyphenyl) propane, 3, 3-bis (3
-Aminophenoxyphenyl) sulfone, 4,4-bis (3-aminophenoxyphenyl) sulfone, 3,3-
Bis (3-aminophenoxyphenyl) sulfone, 4,
4-bis (4-aminophenoxyphenyl) sulfone,
2,2-bis (3-aminophenoxyphenyl) hexafluoropropane, 2,2-bis (4-aminophenoxyphenyl) hexafluoropropane, 1,4-bis (4-aminophenoxy) benzene, 4,4- ( p-phenylene diisopropylidene) bisaniline, 4,4-
A diamine having three or more aromatics such as (m-phenylenediisopropylidene) bisaniline can be used.

Further, the following general formula (4) has a functional group reactive with a thermosetting resin in a part of the aromatic diamine.

Embedded image (However, in the formula, Ar ₃ represents a trivalent or tetravalent aromatic group, X represents a hydroxyl group, an amino group, a carboxyl group, m
It is also possible to add an aromatic diamine represented by 1).

Examples of this aromatic diamine include 2,5
-Diaminophenol, 3,5-diaminophenol,
4,4 '-(3,3'-dihydroxy) diaminobiphenyl, 4,4'-(2,2'-dihydroxy) diaminobiphenyl, 2,2'-bis (3-amino-4-hydroxyphenyl) hexafluoro Propane, 3,3 ',
4,4'-biphenyltetraamine, 3,3 ', 4
4'-tetraaminodiphenyl ether, 4,4'-
(3,3′-dicarboxy) diphenylamine, 3,
3'-dicarboxy-4,4'-diaminodiphenyl ether and the like can be mentioned, and particularly preferably 4,4'-
(3,3′-dihydroxy) diphenylamine, 4,
It is 4 '-(2,2'-dihydroxy) diphenylamine. The use of these aromatic diamines reacts with the epoxy resin or the cyanate resin during thermocompression bonding to form a crosslinked structure, so that the adhesive strength and chemical resistance of the heat-resistant prepreg of the present invention can be further improved.

The silicone-modified polyimide resin is prepared by reacting the above-mentioned diaminosiloxane and aromatic diamine with a tetracarboxylic dianhydride in a solvent to form a precursor resin, which is then ring-closed by heating to give the above-mentioned general formulas (1) and ( A polyimide resin having a repeating unit represented by 2) can be produced. At this time, the constitutional ratio of the repeating units represented by the general formulas (1) and (2) is (1) / (2) = 50/5.
It is preferably in the range of 0 to 10/90. When the constitutional ratio of the repeating unit represented by the general formula (1) is less than 50, the fluidity of the resin is insufficient, and the filling property into the irregularities on the circuit surface is insufficient. Further, when it exceeds 90, the heat resistance and chemical resistance of the resin are inferior, smear is significantly generated during drilling, and the reliability of the obtained through hole is poor.

As the thermosetting resin to be mixed with the linear polyimide resin at the same time, any thermosetting resin such as urethane resin, formal resin, maleimide resin, cyanate resin can be selected, but epoxy resin is particularly preferable. is there.

When an epoxy resin is used as the thermosetting resin, the mixing ratio of the linear polyimide resin and the epoxy resin is 70 to 99% by weight of polyimide and 1 to 30 of epoxy resin.
It is preferably in the range of% by weight. By blending within this range, the adhesiveness and heat resistance can be improved without deteriorating the original properties of the polyimide.

Examples of the epoxy resin include bisphenol A, bisphenol F, bisphenol S, fluorene bisphenol, 4,4'-biphenol and 2,2 '.
-Phenols such as biphenol, hydroquinone, resorcin, or tris (4-hydroxyphenyl)
Trivalent or higher valent phenols such as methane, 1,1,2,2-tetrakis (4-hydroxyphenyl) ethane, phenol novolac and o-cresol novolac, 4,4 ′
-Diglycidyl diaminodiphenylmethane, 1-glycidyl ether, 3-diglycidylaminobenzene, 1,
3-diglycidyl diaminomethylbenzene can be mentioned, but for applications requiring flame retardancy, glycidyl ether compounds derived from halogenated bisphenols such as tetrabromobisphenol A and polyglycidyl ether of brominated novolak phenol novolac are used. preferable.

When the above-mentioned epoxy resin is used, an epoxy resin curing agent may be added for the purpose of promoting curing. Examples of the epoxy resin curing agent include phenol novolac, o-cresol novolac, phenol resole, diethylenetriamine, pyromellitic dianhydride,
Phthalic anhydride may be mentioned.

In addition to the above-mentioned components, conventionally known curing accelerators, coupling agents, inorganic fillers, fibrous fillers, pigments and the like may be appropriately blended.

As the base material in the present invention, a non-conductive inorganic material or organic material can be used. Examples thereof include quartz glass, inorganic fibers such as asbestos, polyamide, polyester, polyacryl, polyvinyl alcohol, polyimide, organic fibers such as fluororesin, woven fabric of natural fibers such as cotton, non-woven fabric, paper, mat and the like. Preferably, it is a glass fiber woven fabric, a polyaramid fiber woven fabric or a non-woven fabric.

The prepreg for a printed wiring board of the present invention is
It is prepared by a conventional dry coating method using a solvent. That is, the base material is impregnated with the resin solution, and then the solvent is dried by heating to form a prepreg. The content weight ratio of the resin composition to the base material in the prepreg can be set arbitrarily, but is preferably in the range of 30/70 to 80/20. When the content of the resin composition is less than 30%, the filling property into the circuit is not sufficient, and when it exceeds 80%, the dimensional stability becomes low, and warp is likely to occur after lamination, which is not preferable.

Typical solvents used in the prepreg molding step are N, N-dimethylformamide, N, N-diethylformamide, N, N-dimethylacetamide, N, N-diethylacetamide,
N, N-dimethylmethoxyacetamide, dimethyl sulfoxide, N-methyl-2-pyrrolidone and other amide solvents, tetrahydrofuran, diethylene glycol dimethyl ether, diethylene glycol diethyl ether,
Examples thereof include dioxane, γ-butyrolactone, xylenol, chlorophenol, phenol, methyl cellosolve, ethyl cellosolve, methyl cellosolve acetate, ethyl cellosolve acetate, ethers such as toluene, xylene, and methyl ethyl ketone, and alcohol solvents. Further, the solvent used in the production of the polyimide resin may be used as it is as the solvent for the prepreg molding. The drying temperature of the solvent is preferably a temperature above the boiling point of the solvent.

Examples of the cyanate resin include bisphenol A dicyanate, tetramethylbisphenol A dicyanate, hexafluorobisphenol A dicyanate, 4,4 '-[1,3-phenylene bis (1-methylethylidene)] dicyanate and their prepolymers. Examples thereof include polymers.

The thus obtained prepreg for a printed wiring board can be used as an adhesive sheet for a multilayer board, an insulating protective sheet or a metal-clad laminate. In the case of a metal-clad laminate, a predetermined number of prepregs for a printed wiring board of the present invention are laminated, a metal foil or an inner layer circuit board is laminated on one side or both sides as necessary, and a metal-clad laminate is formed by a method of heating and pressing to cure. Can be made.

As the metal foil, it is possible to use copper, aluminum, brass, nickel, chromium, iron or the like alone, alloy, or composite foil. Moreover, the temperature and the range of 140-250 degreeC are preferable, and the conditions of pressure-hardening are 20-.
The range of 80 kg / cm ² is preferable, and the pressurization time is 30 to
A range of 480 minutes is preferred. If the temperature, pressure, and time ranges deviate from the above ranges, the heat resistance of the metal-clad laminate decreases.

[0030]

EXAMPLES Next, the present invention will be described with reference to examples, but the present invention is not limited to these examples. The abbreviations used in this example indicate the following compounds. ODPA: 3,3 ', 4,4'-diphenyl ether tetracarboxylic dianhydride DSDA: 3,3', 4,4'-diphenylsulfone tetracarboxylic dianhydride BTDA: 3,3 ', 4,4' -Benzophenone tetracarboxylic acid dianhydride BPDA: 3,3 ', 4,4'-biphenyltetracarboxylic acid dianhydride TMEG: ethylene glycol bistrimellitate dianhydride PSX-A: diaminosiloxane having an average molecular weight of 740 PSX- B: diaminosiloxane having an average molecular weight of 1240 PSX-C: diaminosiloxane having an average molecular weight of 2000 BAPP: 2,2'-bis (4-aminophenoxyphenyl) propane BAPSM: bis (3-aminophenoxyphenyl) sulfone BisAM: 4,4 -(M-phenylenediisopropylidene) bisaniline B sAF-A: 2,2- (4-aminophenoxyphenyl) hexafluoropropane o-DAP: 2,5-diaminophenol o-HAB: 4,4 ′-(3,3′-dihydroxy) diaminobiphenyl m-HAB : 4,4 '-(2,2'-dihydroxy) diaminobiphenyl POPA-A: Polyoxypropylenediamine having an average molecular weight of 230 POPA-B: Polyoxypropylenediamine having an average molecular weight of 400 DGEBA: Bisphenol A type epoxy resin (190
g / eq) o-CNB: o-cresol novolac type epoxy resin (275 g / eq) DGAPM: 4,4′-diglycidyl diaminodiphenylmethane (120 g / eq) BCNB: polyglycidyl ether of brominated phenol novolac (200 g / eq) ) BADC: Bisphenol A dicyanate PNB: Phenol novolac 2MZ: 2-methylimidazole

Example 1 ODPA 37.1 in a 1000 ml separable flask.
4 g (0.11 mol), N-methyl-2-pyrrolidone 2
00g and diethylene glycol dimethyl ether 20
0 g was added and mixed well at room temperature. Next, PSX-A3
1.56 g (n = 8.4, 0.035 mol) was added dropwise using a dropping funnel, and the reaction solution was ice-cooled with stirring to obtain BAPP3.
0.3 g (0.075 mol) was added, and the mixture was stirred at room temperature for 2 hours to obtain a polyamic acid. This polyamic acid solution was heated to 190 ° C., heated and stirred for 20 hours, and ring-closed while azeotroping diethylene glycol dimethyl ether and condensed water to obtain a polyimide solution having a logarithmic viscosity of 0.9 dl / g.

Next, the solid content of the obtained polyimide solution is 7
5 parts by weight of o-cresol novolac type epoxy resin (Yukaka Shell Epoxy Co., Ltd., Epicoat 180)
H-65) 25 parts by weight, and further N-methyl-2-
20 g of pyrrolidone was added and stirred at room temperature until uniform. This resin solution was impregnated into a glass cloth (Arisawa Seisakusho Co., Ltd., 1080) having a thickness of 0.60 μm and then dried at a temperature of 180 ° C. at a speed of 3 m / min to remove the solvent to obtain a prepreg. .

Thermogravimetric measuring device T for this prepreg
The resin amount measured by GA was 60%. The prepreg was cut into 100 mm square pieces, and the volatile matter was measured from the change in weight after heating at 150 ° C. for 20 minutes, and it was 0.4%. Thermo-mechanical analysis of this prepreg T
The glass transition point by MA was 125 ° C., and the linear expansion coefficient from room temperature to the glass transition point was 10 × 10 ⁻⁶ / ° C. The tensile strength at break, the tensile elastic modulus, the dielectric constant, and the dielectric loss tangent of this prepreg were measured based on JIS-C2330. Table 2 shows the results.

The prepreg thus obtained was processed into two polyimide films (Kagafuchi Chemical Co., Ltd., Apical).
It was then sandwiched between 180 ° C., 60 minutes, and a pressure-bonding test was conducted under the conditions of 25 kg / cm ^{−2. As} a result, the adhesive strength by the 180 ° peel test was 2.4 kg / cm. Similarly, two pieces of the oxidized copper foil and the sulfuric acid-treated copper foil were thermocompression bonded under the same conditions, and the adhesive strength was measured by a 180 ° peel test. Each was 1.8 kg / cm,
It was 1.2 k / cm. After heat-pressing the copper foil under the same conditions and immersing it in a solder bath at 300 ° C. for 30 seconds, the adhesion state was observed, but no swelling or peeling was observed, indicating good solder heat resistance. . Prepreg and copper foil (3
(5 μm) was subjected to thermocompression bonding under the same conditions and the dimensional change rate was measured to be −0.02%.

Further, when the prepreg and the copper foil (35 μm) were pressure-bonded at 220 ° C. for 30 minutes under the condition of 40 kg / cm ⁻² to produce a copper-clad laminate, warpage and waviness were not observed. . Furthermore, the copper foil of this copper-clad laminate is processed into a circuit with a line width of 0.1 mm and a line spacing of 1 mm, and the patterns are made to face each other at right angles through the prepreg at 180 ° C for 60 minutes
After press-bonding under a condition of 25 kg / cm ⁻² , the filling property to the circuit was observed, but no voids or unfilled parts were observed and good filling property was shown.

Example 2 DSDA 38.4 in a 1000 ml separable flask.
4 g (0.11 mol), dimethylacetamide 250 g
And m-xylene (150 g) were added and mixed well at room temperature. Next, PSX-A31.56g (n = 8.4, 0.035mol)
Was added dropwise using a dropping funnel, the reaction solution was cooled with ice under stirring, and 30.3 g (0.075 mol) of BAPP was added to obtain a polyamic acid. 160 of this polyamic acid solution
The temperature was raised to 0 ° C., the mixture was heated and stirred for 20 hours, and the ring was closed while azeotropically distilling m-xylene and condensed water to obtain a polyimide solution having a logarithmic viscosity of 0.6 dl / g.

Next, the solid content of the obtained polyimide solution was 7
To 5 parts by weight, 25 parts by weight of a brominated novolak type epoxy resin (BREN-S manufactured by Nippon Kayaku Co., Ltd.) was blended,
Further, 15 g of dimethylacetamide was added, and the mixture was stirred at room temperature until uniform. An aramid non-woven fabric having a thickness of 0.66 μm (manufactured by Dupon Corp .; THERMO
UNT E-220) after impregnation, the temperature of 160 ℃,
Dry to remove the solvent at a speed of 3 m / min,
I got a prepreg.

For this prepreg, the amount of resin, volatile matter, glass transition point, tensile breaking strength, tensile elastic modulus, linear expansion coefficient, adhesive strength, solder heat resistance, dimensional change rate, and filling property were measured in the same manner as in Example 1. went. The physical properties are shown in Table 2.

Examples 3 to 8 After preparing a resin solution having the composition shown in Table 1, a prepreg was prepared and the same properties as in Example 1 were measured. Its composition is shown in Table 1.
The physical properties are shown in Table 2.

Example 9 TMEG 45.1 was added to a 1000 ml separable flask.
0 g (0.11 mol), N-methyl-2-pyrrodone 25
0 g and m-xylene 150 g were added and mixed well at room temperature. Next, 25.30 g of POPA-A (n = 2.6, 0.11 mol; manufactured by Texaco Chemical Co., Ltd.) was added while stirring under ice cooling, and this reaction solution was stirred at room temperature for 2 hours to obtain a polyamic acid. . This polyamic acid solution at 160 ° C
The temperature was raised to 0, and the mixture was heated and stirred for 20 hours, and the ring was closed while azeotropically distilling m-xylene and condensed water to obtain a polyimide solution having an inherent viscosity of 0.5 dl / g.

Next, the solid content of the obtained polyimide solution was 7
To 5 parts by weight, 25 parts by weight of bisphenol A type epoxy resin (Epicoat 828, manufactured by Yuka Shell Epoxy Co., Ltd.) was added, and 15 g of N-methyl-2-pyrrodone was further added, and the mixture was heated to room temperature until uniform. And stirred.

This resin solution was impregnated with 0.80 μm-thick glass cloth (Arisawa Seisakusho Co., Ltd .; 0808) and dried at a temperature of 160 ° C. at a speed of 3 m / min to remove the solvent to obtain a prepreg. Got

For this prepreg, the amount of resin, volatile matter, glass transition point, tensile breaking strength, tensile elastic modulus, linear expansion coefficient, adhesive strength, solder heat resistance, dimensional change rate, and filling property were measured in the same manner as in Example 1. went. The physical properties are shown in Table 2.

Comparative Example 1 After preparing a resin solution having the same composition as in Example 1, this resin solution was applied onto a glass plate and dried to form a film, which was used as an adhesive film.

The glass transition point of this adhesive film by thermomechanical analysis TMA was 115 ° C., and the linear expansion coefficient from room temperature to the glass transition point was 50 × 10 ⁻⁶ / ° C. About this adhesive film, tensile breaking strength, tensile modulus,
Dielectric constant, dielectric loss tangent, adhesive strength, solder heat resistance, and filling property were measured in the same manner as in Example 1. Table 3 shows the results.

Further, this adhesive film and copper foil are
Thermocompression bonding under conditions of 25 kg / cm ^-2 for 60 minutes at ℃,
When the dimensional change rate before and after crimping was measured, it was -0.30%.
Therefore, the warp to the copper foil side occurred.

Comparative Example 2 A polyimide solution having the same composition as in Example 2 was prepared, and
66 μm thick polyaramid non-woven fabric (manufactured by Dupont;
THERMOUNT E220) was impregnated and then dried to remove the solvent at a temperature of 160 ° C. and a speed of 3 m / min to obtain a prepreg. The same characteristics as in Example 1 were measured for this prepreg. The characteristics are shown in Table 3.

Comparative Example 3 50 parts by weight of a brominated novolac type epoxy resin (BREN-S manufactured by Nippon Kayaku Co., Ltd.) was added to a 1000 ml flask.
Phenol novolac (Pump manufactured by Gunei Chemical Industry Co., Ltd.)
-4324) 48 parts by weight, 2-methylimidazole 2 parts by weight, and methyl ethyl ketone 400 parts by weight were added and stirred at room temperature for 2 hours to prepare an epoxy resin solution.

A glass cloth having a thickness of 0.60 μm (1080 made by Arisawa Seisakusho Co., Ltd.) was impregnated with this resin solution, and then dried at a temperature of 100 ° C. at a speed of 3 m / min to remove the solvent, and prepreg was prepared. Got

The same properties as in Example 1 were measured for this prepreg. Its composition is shown in Table 1 and its physical properties are shown in Table 3.

Comparative Examples 4 to 7 After preparing a resin solution having the composition shown in Table 1, a prepreg was prepared in the same manner as in Example 1 and the same physical properties as in Example 1 were measured. Its composition is shown in Table 1 and its physical properties are shown in Table 3.

[0052]

[Table 1]

[0053]

[Table 2]

[0054]

[Table 3]

[0055]

The prepreg for printed circuit board of the present invention is
Compared to conventional polyimide adhesives, thermocompression bonding is possible at 200 ° C or lower without compromising the original heat resistance, chemical resistance, and electrical characteristics of polyimide, and the expansion coefficient after pressure bonding and curing is low. It is characterized by excellent dielectric properties and dimensional stability. Therefore, the heat-resistant prepreg for a printed circuit board according to the present invention can be suitably used as an adhesive for a multilayer printed circuit board, an adhesive for a composite circuit board, an insulating protective sheet and the like. In addition, a heat-resistant prepreg for a printed circuit board of the present invention can be used in a metal-clad laminate having the above-mentioned properties by laminating a metal foil on one side or both sides.

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Claims (6)

[Claims] 1. A prepreg for a printed wiring board obtained by impregnating a base material with a resin composition comprising a linear polyimide resin and a thermosetting resin. 2. The glass transition point of the resin composition is 60 to 17.
The heat resistant prepreg for printed wiring according to claim 1, wherein the temperature is 0 ° C. 3. The prepreg for a printed wiring board according to claim 1, wherein the substrate is a substrate made of glass fiber or aramid fiber. 4. The content weight ratio of the resin composition and the base material is 30 /.
70-80 / 20, It is characterized by the above-mentioned 1-3.
A prepreg for a printed wiring board according to any one of 1. 5. The prepreg for a printed wiring board according to claim 1, wherein the linear polyimide resin is a silicone-modified polyimide resin and the thermosetting resin is an epoxy resin. 6. A metal-clad laminate obtained by thermocompressing a metal foil on one side or both sides of the prepreg according to claim 1.