JPH05162129A - Manufacture of prepreg - Google Patents

Abstract

PURPOSE:To obtain a prepreg which has no uneven surface and internal foaming, by drying a base material impregnated with a resin by drying air flow of 0.2-2m/sec speed. CONSTITUTION:A base material impregnated with a resin is dried in drying air flow of 0.2-2m/sec speed, and purged with an inert gas as required, thus manufacturing a prepreg. The resin of the resin-impregnated base material is prepared by adding inorganic powder fillers such as talc, clay, silica, calcium carbonate, aluminum hydroxide, etc., to a resin such as of a phenol resin, an epoxy resin, an unsaturated polyester resin, a polyimide resin, a polyamide resin, a polyethylene terephthalate resin, etc., alone, their modified resin, or their mixture as required. A woven fabric a nonwoven fabric, paper, etc., composed of inorganic fibers such as of glass, ceramic, etc., the organic fibers of vinyl alcohol, polyimide, etc., and natural fibers such as of cotton are employed as the base material. Accordingly, the prepreg which has no uneven surface and internal foaming, is acquired.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to electronic equipment, electric equipment,
The present invention relates to a method for manufacturing a prepreg for laminated plates used in computers, communication devices and the like.

[0002]

2. Description of the Related Art Conventionally, prepreg is an organic solvent in resin,
In order to avoid the explosion caused by the monomer, it was dried by using a hot air dryer or a radiant heat dryer to increase the wind power. Therefore, it is dried at a wind speed of 3 m / sec or more, but in a hot air dryer, the heat transfer from the air causes the temperature to rise from the surface of the resin-impregnated base material into a foamed state, resulting in surface irregularities, resulting in a prepreg with a lot of internal foaming. Become. Also, the radiant heat dryer can be improved as compared with the hot air dryer, but it is still not in a satisfactory state. Further, as a common drawback, there is a problem that the solvent rising speed becomes faster and foaming is more likely to occur.

[0003]

As described in the prior art, there is a problem in drying the conventional resin-impregnated base material. The present invention has been made in view of the above problems in the prior art, and an object of the present invention is to provide a method for producing a prepreg having no surface irregularities and no internal foaming.

[0004]

The present invention is characterized in that a base material impregnated with a resin is dried at a drying air velocity of 0.2 to 2 m / sec and, if necessary, purged with an inert gas. The above object can be achieved because of the method of manufacturing a prepreg, and the present invention will be described in detail below.

The resin of the resin-impregnated base material used in the present invention includes phenol resin, epoxy resin, unsaturated polyester resin, polyimide resin, polyamide resin, polyethylene terephthalate resin, polybutylene terephthalate resin,
Polyphenylene sulfide resin, polyphenylene oxide resin, fluorine resin, polybutadiene resin, etc., alone, modified, or mixed resin, with inorganic powder filler such as talc, clay, silica, calcium carbonate, aluminum hydroxide added as necessary. Is. As the base material, inorganic fibers such as glass, ceramics and asbestos,
Examples thereof include vinyl alcohol, polyimide, polyethylene terephthalate, polybutylene terephthalate, polyamide, polyphenylene sulfide, polyphenylene oxide, woven fabrics, non-woven fabrics and papers made of organic fibers such as fluororesin and natural fibers such as cotton. The amount of resin with which the substrate is impregnated is preferably 35 to 70% by weight as a resin solid content. Further, the resin may be impregnated only with the same resin, but may be made into a plurality of impregnations such as primary impregnation and secondary impregnation with the same resin or different type resin so that the impregnation becomes more uniform. As the dryer, a general dryer such as a hot air dryer or a radiant heat dryer can be used, but the drying wind speed is 0.2 to 2
It is necessary to dry at m / sec. That is 0.2 m
This is because if it is less than / sec, the drying property is deteriorated, and if it exceeds 2 m / sec, surface irregularities and internal foaming are not eliminated. For safety,
If necessary, it is purged with an inert gas such as nitrogen gas. Further, the dryer may be of any type such as vertical type or horizontal type, but it is preferable to use the vertical type. The present invention will be described below based on examples.

[0006]

[Example] A resin-impregnated base material, in which a hardener-containing epoxy resin was dried on a glass woven cloth having a thickness of 0.2 mm so that the amount of the resin was 45% by weight, was sent to a vertical radiant heat dryer, and dry wind was applied. It was dried at 0.8 m / sec to obtain a prepreg.

[0007]

[Comparative Example] A prepreg was obtained by treating in the same manner as in Example except that the dry wind power was changed to 3 m / sec.

Table 1 shows the performance of the prepregs of Examples and Comparative Examples.

[0009]

[Table 1]

[0010]

The present invention is constructed as described above. In the method for producing a prepreg having the structure described in the claims, it was confirmed that the present invention was excellent because there were no surface irregularities or internal foaming.

Claims (1)

[Claims] 1. A dry air velocity of 0.2
A method for producing a prepreg, which comprises drying at ˜2 m / sec and purging with an inert gas as necessary.