JPH0376760A - Thermosetting resin composition - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention has excellent not only heat resistance but also moldability and high-temperature mechanical properties, and can be used as an interlayer insulation material for semiconductors, HICs, printed wiring board materials, etc. The present invention relates to a thermosetting resin composition that can be used.

[Prior art/problems to be solved by the invention] Polyimide resin is the most typical heat-resistant material used as interlayer insulation material (MOL, August 1985 issue, 28- (See page 36).

Conventionally, as a method for forming polyimide, a method has been used in which a polyamic acid varnish, which is a polyimide precursor, is used, the solvent of the varnish is dried, and then the varnish is cured by heating to form a polyimide film. However, this method has problems such as polyamic acid is chemically unstable, condensed water generated during imidization can cause voids, and heating to high temperatures is required for curing. There is.

In order to solve these problems, cyclization condensation (imidization)
Soluble thermoplastic polyimides that are soluble in organic solvents even in a high molecular weight state have been developed. However, such thermoplastic polyimides have extremely high varnish viscosity and poor moldability, and unlike thermosetting resins, they suffer from high-temperature mechanical properties such as being deformed by heat even once shaped. It has the disadvantage of being inferior to

[Means for Solving the Problems] The present invention not only has excellent heat resistance, etc., but also has excellent moldability and can form thick films, has excellent high-temperature mechanical properties, and is suitable for interlayer insulation materials. The purpose is to provide a thermosetting resin composition that can be widely used, and includes a soluble polyimide represented by (wherein, n represents an integer) and general formula (1): (wherein, Ar represents a divalent aryl group).

[Example] A soluble polyimide represented by the following formula (wherein n represents an integer) is used.

This soluble polyimide is soluble in solvents such as γ-butyrolactone and N-methyl-2-pyrrolidone, so this polyimide can be dissolved in a solvent as it is to make a varnish, and it is chemically stable and can be used at relatively low temperatures. Film can be formed using

The soluble polyimide represented by the general formula (I) preferably has an intrinsic viscosity of 0.2 to 5.0 dl/g (in γ-butyrolactone, 30°C).

Such a polyimide can be produced by a conventional method from a corresponding acid anhydride and an amine.

The composition of the present invention has the following formula (■): Contains bismaleimide.

Ar in the general formula (1) is not particularly limited as long as it is a divalent aryl group.

Specific examples of such bismaleimides include N,N'-(methylenedi-p-phenylene)bismaleimide, N,N'-(sulfonedi-p-phenylene)bismaleimide, and N,N'-(oxydi-p-phenylene)bismaleimide. p-phenylene)
Bismaleimide, N,N'-(sulfonedi■-phenylene)bismaleimide, N,N'-2,4-tolylenebismaleimide, N,N'-2,6-tolylenebismaleimide, N,N' -Otori-phenylene bismaleimide, N
, N'-p-phenylene bismaleimide, N,N'-ethylene bismaleimide, N,N'-hexamethylene bismaleimide, and the like. These may be used alone or in combination of two or more.

Regarding the blending ratio of soluble polyimide and bismaleimide, it is preferable that the ratio of bismaleimide in the total solid component of both is 10 to 80% (weight %, the same applies hereinafter). If the blending ratio of bismaleimide is less than 10%, the fluidity of the resulting resin composition varnish will be low and the processability will be reduced, making it difficult to form a thick film. The mechanical strength of the cured product of the composition tends to decrease.

Although there are no particular limitations on the method for preparing the resin composition of the present invention, for example, soluble polyimide, bismaleimide, etc.
A common method is to mix them in an organic solvent such as -methyl-2-pyrrolidone or γ-butyrolactone to form a resin composition varnish.

The resin composition varnish thus obtained can be cast onto a glass plate or the like, dried, and then heated and cured to form a cured film. Alternatively, an uncured product that has been cast onto a glass plate or the like and dried can be used as a film sheet as it is. That is, instead of the commonly used glass/epoxy prepreg, an uncured film sheet is used, laminated in the same manner as glass/epoxy, and then thermally cured.
It can be used as an interlayer insulating film for printed circuit boards. In addition, it is also possible to impregnate a base material such as glass cloth or carbon cloth and dry it to use it as pudding or leg. Moreover, the above-mentioned well-known fillers, reinforcing materials, etc. can be blended and used as a composite material.

As described above, the resin composition of the present invention has a low varnish viscosity that allows the formation of a thick film, has flexibility that allows processing into a sheet even in an uncured state, and is chemically It is stable, and by thermosetting it becomes a cured product that is tough, heat resistant, and has excellent high-temperature mechanical properties.

EXAMPLES The resin composition of the present invention will be explained in detail below based on Examples, but the present invention is not limited to these Examples.

Example 1 and Comparative Example 1 5% γ of soluble polyimide represented by general formula (11)
-Butyrolactone solution (70 cps, 25°C) 200
By mixing 5.4 g of N,N'-(methylenedi-p-phenylene) bismaleimide with g and stirring at room temperature for 1 hour to make them compatible, a soluble polyimide/bismaleimide with a resin content of 7.5% was obtained. A varnish with a uniform resin composition having a ratio of about 2/l was obtained.

This varnish was cast onto a glass plate, dried at 80°C for 30 minutes while open, and then heated and cured at 200°C for 1 hour, 250°C for 30 minutes, and 350°C for 1 hour to harden the film thickness to 35Ia. I got the film.

The high-temperature mechanical properties (penetration behavior at elevated temperature) of the resulting cured film were investigated. The results are shown in Figure 2.

In addition, as a comparative example, a cured film was prepared by preparing a varnish containing only the above-mentioned soluble polyimide at the same concentration, and the high-temperature mechanical properties of the film were investigated.
It was as follows. From the results shown in Figure 2, the glass transition temperature of the cured film made of the composition of the present invention is 350°C.
From the above, it was found that the mechanical properties at high temperatures are considerably improved compared to the film made only of the soluble polyimide represented by the general formula (1). Furthermore, it was found that the viscosity of the varnish of the composition of the present invention was reduced to about half that of a varnish of the same concentration containing only soluble polyimide.

Incidentally, Figure 1 shows the varnish obtained by examining the viscosity at 20°C of a varnish prepared by dissolving the above-mentioned soluble polyimide and bismaleimide in γ-butyrolactone so that the resin concentration was 20%. FIG. 2 is a graph showing the relationship between viscosity and the proportion of bismaleimide in the total resin content of Varnish 7, and FIG. 2 is a graph showing the relationship between needle depth and temperature in a cured product from the resin composition of the present invention. It is.

Example 2 The viscosity of the varnish was measured in the same manner as in Example 1 except that the mixing ratio of soluble polyimide/bismaleimide in Example 1 was changed to 1/1 by weight.
) It was found that the viscosity was lowered to about 173 compared to the viscosity of a varnish containing only soluble polyimide.

Then, a cured film with film thicknesses ao and n was produced in the same manner as in Example 1, and the high-temperature mechanical properties (penetration behavior at elevated temperature) of this film were measured. The results are shown in the mountains in Figure 2. From Figure 2 (b), the glass transition temperature of the cured film is 35
0°C or higher, and the mechanical properties at high temperatures are those of general formula (I)
It was found that this was considerably improved compared to a film made only of polyimide represented by

Example 3 10% γ-butyrolactone solution 1 of soluble polyimide represented by the same general formula (1) as used in Example 1
00g l: N,N'-(sulfonedi-p-phenylene)bismaleimide lO,og were mixed and stirred at room temperature for 1 hour to make them compatible, resulting in a resin content of 18.2
The weight ratio of % soluble polyimide/bismaleimide is 1/
A varnish with a uniform resin composition of No. 1 was obtained.

The obtained varnish was cast onto a glass plate, dried at 80°C for 30 minutes, and then heated and cured at 200°C for 1 hour, 250°C for 30 minutes, and 350°C for 1 hour to obtain a film thickness of approximately 3.
After 2 printings, a strong film with a glass transition temperature of 350°C or higher was obtained.

[Effects of the Invention] The resin composition of the present invention not only has excellent stability, flexibility, and heat resistance, but also has a low viscosity of varnish, so it has high moldability and can be formed into a thick film.

Furthermore, since the cured product has improved high-temperature mechanical properties, it can be applied to various uses such as interlayer insulation films.

[Brief explanation of drawings]

FIG. 1 is a graph showing the relationship between the varnish viscosity of the resin composition of the present invention and the proportion of bismaleimide in the solid content of the varnish;
FIG. 2 is a graph showing the thermomechanical property measurement results (TMA, penetration method) of a cured product from the resin composition of the present invention, and is a graph showing the relationship between penetration amount and temperature. Agent Masuo Hitoishi Viscosity (CplS) Needle insertion amount→

Claims (1)

[Claims] (1) General formula (I): ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ Soluble polyimide represented by (I) (in the formula, n represents an integer) and general formula (II): ▲ Numerical formulas, chemical formulas, tables, etc. ▼(II) A thermosetting resin composition consisting of bismaleimide represented by (wherein, Ar represents a divalent aryl group).