Tonen Corporation

Toa Nenryo Kogyo Kabushiki Kaisha

Sadahisa Wada

Hiroshi Inoue

Osamu Watanabe

Shinkichi Murakami

Makoto Miyazaki

Makiji Miyao

Makoto Takezawa

Shinichi Murakami

Osamu Watanebe

The present invention relates to a hybrid prepreg having reinforcing carbon fibers and foreign fibers. The carbon fibers have a diameter ranging from 5-30 microns and are unidirectionally arranged. The foreign fibers are composed either of single monofilaments having a diameter ranging from between about 50-150 microns or of strands formed by bundling together a plurality of single monofilaments having a diameter ranging from between about 5-50 microns. If strands are employed, they have a conversion diameter (D.sub.0) which is less than about 500 microns. The conversion diameter (D.sub.0) is represented by the following equation: ##EQU1## wherein n is the number of monofilaments used in forming the strand, and wherein d is the diameter of these monofilaments. Examples of foreign fibers which can be used when practicing this invention include boron fibers, metal fibers and organic fibers. These foreign fibers are spaced at fixed intervals, arranged in the same direction as the direction of the reinforcing carbon fibers, and positioned approximately at or near the center of the resulting prepreg. The prepreg prepared in accordance with the present invention also includes a thermosetting matrix resin in which the reinforcing carbon fibers and the foreign fibers are impregnated.

Method of making a hybrid prepreg

An epoxy resin composition useful as a matrix for fiber-reinforced composites is disclosed which includes a mixture containing 30-95% by weight of a tetrafunctional epoxy resin, 3-40% by weight of an admixture of trifunctional epoxy resin oligomers and 2-50% by weight of a bisphenol A epoxy resin having a number average molecular weight of 450-1,300 and such a weight average molecular weight as to provide a ratio of the weight average molecular weight to the number average molecular weight of 1.3-3.0.

Composition of tetraglycidyl, triglycidyl and diglycidyl epoxy resins

Hybrid prepreg containing carbon fibers and at least one other

A two component-type curing agent composition is disclosed which comprises a first curing agent which is capable of cross-linking an epoxy resin and which is at least one member selected from primary amines, phenolic compounds and acid anhydrides, and a second curing agent which is at least one compounds represented by the following general formula: ##STR1## wherein X is --CR.sub.1 R.sub.2 --, --CO--, --COO--, --SO.sub.2 --, --SO--, --S--, --O--, --NR.sub.1 --, --SiR.sub.1 R.sub.2 -- or --POR.sub.1 -- where R.sub.1 and R.sub.2 each stands for hydrogen, a lower alkyl or a phenyl; Y and Y' each stands for hydrogen, a lower alkyl or an electron attracting group; R is a lower alkyl; and m and n each is an integer of 1-4.

Epoxy resin curing agent based on blends containing disecondary aromatic

A new thermosetting resin composition is disclosed which comprises a Bisphenol A-type epoxy resin having a number average molecular weight of smaller than 650 but not smaller than 450 and a ratio of the weight average molecular weight thereof to the number average molecular weight thereof of in the range of 1.3-3.0; and a curing agent capable of cross-linking the epoxy resin. The curing agent is preferably a compound represented by the following general formula: ##STR1## wherein X is --CR.sub.1 R.sub.2 --, --CO--, --COO--, --SO.sub.2 --, --SO--, --S--, --O--, --NR.sub.1 --, --SiR.sub.1 R.sub.2 -- or --POR.sub.1 -- where R.sub.1 and R.sub.2 each stands for hydrogen, a lower alkyl or a phenyl; Y and Y' each stands for hydrogen, a lower alkyl or an electron attractive group; R is a lower alkyl; and m and n each is an integer of 1-4, or a mixture thereof with a primary amine, a phenolic compound or an acid anhydride.

Thermosetting epoxy resin composition

A new thermocurable composition is disclosed which comprises a Bisphenol A-type epoxy resin having a number average molecular weight of 650-1300, 10-40% by weight of the Bisphenol A-type epoxy resin having an epoxy equivalent of 180-195; and a curing agent capable of cross-linking the epoxy resin. The curing agent is preferably a compound represented by the following general formula: ##STR1## wherein X is --CR.sub.1 R.sub.2 --, --CO--, --COO--, --SO.sub.2 --, --SO--, --S--, --O--, --NR.sub.1 --, --SiR.sub.1 R.sub.2 -- or --POR.sub.1 -- where R.sub.1 and R.sub.2 each stands for hydrogen, a lower alkyl or a phenyl; Y and Y' each stands for hydrogen, a lower alkyl or an electron attractive group; R is a lower alkyl; and m and n each is an integer of 1-4, or a mixture thereof with a primary amine, a phenolic compound or an acid anhydride.

Growing community of inventors

Kamifukuoka, Japan

Sadahisa Wada