PURPOSE: To prepare crystalline calcium silicate hydrate having improved heat and fire resistance and heat insulating property on molding into a molded article, by the hydrothermal reaction of calcium silicate hydrate in hot water or hot aqueous solution of an alkali preheated to the reaction temperature.
CONSTITUTION: Water or an aqueous solution of an alkali metallic hydroxide, e.g. NaOH or KOH, in about 1W2 N alkali concentration is introduced into an autoclave, and heated at 100W400°C. 1pt.wt. calcium silicate hydrate, e.g. amorphous calcium silicate hydrate or hydrate of cement, is injected into 100pts.wt. hot water or hot aqueous solution of the alkali by a booster pump to carry out the hydrothermal reaction and give the aimed crystalline calcium silicate hydrate having improved heat and fire resistance and heat insulating property on molding into a molded article and lightweight properties in a short time.
SHIMIZU YUKIHISA
DOI YUUICHI
