Gun Ei Chemical Industry Co., Ltd.

Nippon Kayaku Kabushiki Kaisha

Akiyuki Kojima

Yukio Abe

Yoshiaki Kurimoto

Tsuyoshi Fukuda

Kaori Hasegawa

Ryoichi Hasegawa

Kenichi Kuboki

Yoshio Shimamura

Epoxy resin, epoxy resin composition and hardened product thereof

One of the objects of the present invention is to offer novolak type phenolic resins which use phenols and aldehydes as raw materials and give narrow molecular weight distributions. The novolak type phenolic resins of the present invention are those obtained by condensation reaction of phenols with aldehydes in the presence of an oxycarboxylic acid having carboxyl groups, --COOH, and alcoholic hydroxyl groups, --OH, in one molecule. Thus obtained novolak type phenolic resins show narrow molecular weight distributions, lower viscosity in molten state and, as a consequence, uniformity in curing time.

Novolak type phenolic resins and methods of manufacturing thereof

One of the objects of the present invention is to offer novolak type phenolic resins which use phenols and aldehydes as raw materials and give narrow molecular weight distributions. The novolak type phenolic resins of the present invention are those obtained by condensation reaction of phenols with aldehydes in the presence of an oxycarboxylic acid having carboxyl groups, --COOH, and alcoholic hydroxyl groups, --OH, in one molecule. Thus, obtained novolak type phenolic resins show narrow molecular weight distributions, lower viscosity in molten state and, as a consequence, uniformity in curing time.

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Gunma-ken, Japan

Akiyuki Kojima