Takenaka Corporation

Fujisawa Pharmaceutical Company, Ltd.

Nippon Nyukazai Co., Ltd.

Mitsubishi Materials Corporation

Keihin Ryoko Concrete Industry Corporation

Takemoto Oil and Fat Corporation

Kunio Yanagibashi

Toshio Saito

Masaharu Sakuta

Mitsuo Kinoshita

Mitsuo Sato

Toshio Yonezawa

Kenrou Mitsui

Etsurou Asakura

Tooru Okuno

Yousaku Ikeo

Hisatsugu Yoshida

The hydraulic substance according to the present invention comprises a certain amount of solid particles A (such as portland cement and mixed cement comprising portland cement), an average diameter thereof is 5 to 50 .mu.m, and solid particles B (such as silica fume comprising amorphous silica), an average diameter thereof is less than 1/5 of the particles A, and the particles B have such characteristic that they cohere to the surfaces of the particles A in water, and the quantity of the particles B is arranged such that they cover at least to make a single layer over the whole or part of surfaces of the particles A to cover whole or part of surfaces of particles A with particles B at least with a single layer, and the quantity of the water is arranged such that it is less than 60% of the total amount of the particles A and particles B.

Hydraulic substance with water stable particle coating

The present invention provides a method for improving the durability of cement-hydraulic substances, the method decreasing the dry shrinkage of cement-hydraulic-set substances such as concrete, mortar or related substances, and increasing resistance to a repetition of the freezing and thawing of the cement-hydraulic-set substances, by the use of terminal alkyletherified compounds or terminal alkylesterified compounds of polymers having --C.sub.2 H.sub.5 O-- and/or --C.sub.3 H.sub.6 O-- as a repetitive unit.

Durability improving agent for cement-hydraulic-set substances, method

Growing community of inventors

Narashino, Japan

Kunio Yanagibashi