Kanegafuchi Kagaku Kogyo Kabushiki Kaisha

Hidenari Tsunemi

Toshinobu Nakata

Asaichi Nishimura

Yasuo Fushiki

Yousuke Kawai

Satoshi Tonoki

Koyoyuki Namura

Kunihisa Abe

Dislcosed is a curable composition of a partially trimerized prepolymer of the dicyanate ester of the formula ##STR1## wherein R.sub.1 and R.sub.2 are the same or different and each is alkyl, perfluoroalkyl, aryl or halogen; and A is a bridge selected from the group consisting of a direct bond, methylene optionally mono- or disubstituted by alkyl, perfluoroalkyl and/or aryl, a five or six membered cycloalkylene, sulfonyl, thio, oxy, carbonyl, phenylene, and xylylene optionally substituted by alkyl at on or both methylene carbon atoms is useful in the manufacture of electrical laminates having excellent dielectric properties in the GHz region.

Bifunctional aromatic cyanates, prepolymers and electrical laminates

A novel dicyanate ester of the formula: ##STR1## wherein R.sub.1, R.sub.2, R.sub.3 and R.sub.4 are the same or different and each is hydrogen, alkyl, perfluoroalkyl, aryl or halogen; A is a bridge selected from the group consisting of direct bond, methylene optionally mono- or di-substituted by alkyl, perfluoroalkyl and/or aryl, a five or six membered cycloalkylene, sulfonyl, thio, oxy, carbonyl, phenylene, and xylylene optionally substituted by alkyl at one or both methylene carbon atoms; with the proviso that when the cyanato group is at the para-position relative to the bridge A, both R.sub.1 and R.sub.2 are not hydrogen, and its prepolymer are useful in the manufacture of electrical laminates having excellent dielectric properties in GHz region.

A flame-retarded thermosetting resin composition is provided by blending about 5 to 45 mole % of a phenylcyanate having at least one halogen substituent at the ortho or para position relative to the cyanato group, and about 55 to 95 mole % of a halogen-free bis-4-phenylcyanate. A flame retardancy of V-O grade of UL94 is achieved in the thermoset resin of the composition without compromising dielectric, heat resistance, moisture absorption and other properties.

Flame-retarded thermosetting resin composition, prepregs and electrical

An unsaturated polyester composition is provided comprising an unsaturate polyester component, a cross-linking monomer and as a modifier of the resin a polyoxyalkylene alcohol at least partially esterified with a polymerizable unsaturated carboxylic acid. The modifier is produced by esterifying the hydroxy group of a polyoxyalkylene mono- or polyalcohol at least partially with a polymerizable carboxylic acid such as a maleic acid.

Unsaturated polyester resin compositions and electrical laminates made

An unsaturated polyester composition is provided comprising an unsaturate polyester component, a cross-linking monomer and as a modifier of the resin a polyoxyalkylene alcohol at least partially esterified with a polymerizable unsaturated carboxylic acid. The modifier is produced by esterifying the hydroxy group of a polyoxyalkylene mono- or polyalcohol at least partially with a polymerizable carboxylic acid such as maleic acid.

An unsaturated polyester resin composition is provided comprising a hard unsaturated polyester component, a soft unsaturated polyester component and a cross-linking monomer. The soft polyester component contains a polyoxyalkylene segment having a molecular weight from 600 to 6000 in the backbone thereof and is dispersed in the hard polyester component forming fine particles having a particle size not greater than 4 microns. The resin composition, when cured, exhibits a Tg corresponding to the hard polyester component from 100.degree. C. to 200.degree. C. and another Tg corresponding to the soft polyester component from -100.degree. C. to 0.degree. C.

Growing community of inventors

Adogawacho, Japan

Hidenari Tsunemi