摘要:
Inorganic material comprises a mixture of water glass and metakaolin obtained by heat treating a kaolin group clay mineral at 600.degree. to 900.degree. C. This inorganic material, when solidified by drying, exhibits excellent water resistance, and when solidified by heating to a temperature of 80.degree. to 500.degree. C., exhibits excellent water and hot water resistances. The inorganic material may further contain a hydrous magnesium silicate type clay mineral. Such material, when solidified by drying, exhibits further excellent water resistance and when solidified by heating to a temperature of 80.degree. to 500.degree. C., exhibits excellent resistances to water, hot water and boiling water.