JPH0611779B2 - Thermosetting resin manufacturing method - Google Patents

Description

TECHNICAL FIELD The present invention relates to a method for producing a thermosetting resin which is effective for producing a laminated plate that requires room temperature punching workability and chemical resistance.

2. Description of the Related Art Conventionally, tung oil-modified phenolic resin has been used for a laminated plate which requires punching workability. The tung oil-modified phenolic resin is obtained by reacting phenols with tung oil under an acidic catalyst and then adding formaldehyde to proceed the resolization reaction under a basic catalyst. A phosphoric acid ester compound is added to the tung oil-modified phenolic resin to improve the low temperature punching workability of the laminated plate.

Problems to be Solved by the Invention However, if the addition amount of the phosphate ester compound is increased,
Although the low temperature punching workability of the laminated plate is improved, there is a drawback that the interlayer adhesion in the high temperature region is lowered and the chemical resistance is also remarkably lowered. On the other hand, when the addition amount of the phosphoric acid ester compound is small, the punching temperature range is narrowed and the chemical resistance is somewhat lowered because the phosphoric acid ester compound is added.

It is an object of the present invention to provide a tung oil-modified phenolic resin which is effective in producing a laminate having excellent room-temperature punchability and chemical resistance.

Means for Solving the Problems In order to achieve the above object, the present invention relates to a tung oil-modified phenol in which phenols and tung oil are reacted under an acidic catalyst and then formaldehydes are added to proceed a resolization reaction under a basic catalyst. In the production of resin, a phosphoric acid ester compound is added during the resolization reaction to produce a high molecular weight compound (
≈4000) in the range of 20 to 25% by weight in the reaction product.

Effect The present invention does not add a phosphate ester compound to the produced tung oil-modified phenol resin, but adds a phosphate ester compound during the resolization reaction in the reaction process for obtaining a tung oil-modified phenol resin, thereby punching at room temperature. Thus, a tung oil-modified phenolic resin which is effective for producing a laminate having excellent processability and chemical resistance can be obtained. When the amount of the high molecular weight substance (≈4000) at the end of the reaction is less than 20% by weight, the chemical resistance of the laminate and the interlayer adhesion at high temperature are deteriorated. On the other hand, if the amount of the high molecular weight compound exceeds 25% by weight, the viscosity of the reaction product will sharply increase and there will be a problem in productivity.
When it is made into a laminated plate, the hardness is increased and the punching workability is deteriorated (it becomes a high temperature punching).

EXAMPLES In carrying out the present invention, the molar ratio of phenols to formaldehydes in the resolization reaction is preferably 1.1 to 1.5 moles of formaldehydes to 1 mole of phenols. The tung oil-modified phenolic resin obtained according to the present invention is impregnated into a base material such as paper and dried to form a prepreg, and a predetermined number of the prepreg are laminated and heat-pressed to form a laminate.

Examples will be described below.

Example 1 First, 864 g of phenol, 96 g of orthocresol,
517 g of tung oil and p-toluenesulfonic acid were put into a three-necked flask and reacted at 80 ° C. for 90 minutes. Next, 86%
Paraformaldehyde 422g, triethylamine 38
g, and after 1 hour of the resolization reaction, a phosphoric acid ester (trade name: Reophos) was added to further advance the reaction,
A resin having a high molecular weight (≈4000) in the product of 20% by weight was obtained. Methanol was added to this resin to form a resin-solidified 50% by weight varnish, which was impregnated into an 11 mils paper base material and dried to form a prepreg with a resin amount of 47%. 60 under pressure of ²
After heating and pressurizing for a minute, a 1.6 mm thick copper clad laminate was obtained.

The molecular weight of the reaction product is measured by high performance liquid chromatography analysis.

Example 2 The resolization reaction was carried out in the same manner as in Example 1 to obtain a resin containing 25% by weight of a high molecular weight substance (≈4000) in the product. Methanol was added to this resin to make the resin solid type 50% by weight, and a copper clad laminate having a thickness of 1.6 mm was obtained in the same manner as in Example 1.

Comparative Example 1 The resolization reaction was carried out in the same manner as in Example 1 to obtain a resin having a high molecular weight (≈4000) of 26% by weight in the product. However, this resin had a high viscosity, and it took a long time to dissolve even if methanol was added. Using this varnish, a copper-clad laminate having a thickness of 1.6 mm was obtained in the same manner as in Example 1.

Comparative Example 2 The resolization reaction was carried out in the same manner as in Example 1 to obtain a resin in which the high molecular weight substance (≈4000) in the product was 19% by weight. Methanol was added to this resin to make the resin solid type 50% by weight, and a copper clad laminate having a thickness of 1.6 mm was obtained in the same manner as in Example 1.

Conventional example First, phenol 864g, orthocresol 96g,
517 g of tung oil and p-toluenesulfonic acid were put into a three-necked flask and reacted at 80 ° C. for 90 minutes. Next, 86%
Paraformaldehyde 316g, 37% formalin 24
5 g and 30 g of trimethylamine were added, a resolization reaction was performed at 70 ° C., and dehydration was performed at a gel time of 6 minutes to 6 minutes 30 seconds. After completion of the dehydration, the same phosphoric acid ester and methanol as in Example 1 were added to obtain a resin-solidified 50% by weight varnish, and in the same manner as in Example 1, a 1.6 mm-thick copper clad laminate was obtained.

Table 1 shows the characteristics of the laminates obtained in the above Examples, Comparative Examples and Conventional Examples.

EFFECTS OF THE INVENTION As is clear from Table 1, the laminate using the thermosetting resin according to the present invention has both room temperature stamping workability and chemical resistance. This is because the phosphoric acid ester compound was added in the process of the resolization reaction during the production of tung oil-modified phenolic resin, and the high molecular weight product (≈4000) in the product
Can be achieved by adjusting the content of the compound in the range of 20 to 25% by weight.

In addition, there is no particular problem with heat resistance and the like, and it is possible to provide a laminated plate that sufficiently satisfies the properties particularly required in the electronic device field, and its industrial value is extremely large.

Claims (1)

[Claims] 1. A phosphoric acid ester at the time of resolization reaction in the production of tung oil-modified phenol resin in which phenols and tung oil are reacted under an acidic catalyst and then formaldehydes are added to proceed the resolization reaction under a basic catalyst. A process for producing a thermosetting resin, which comprises adding a compound and reacting so that a high molecular weight substance (≈4000) at the reaction end point is in the range of 20 to 25% by weight in the reaction product.