Process of producing fiber-reinforced hardened body of gypsum system (US Patent 4,146,402, 1979)

Kinichi Kira, Yoshio Makino, Tadashi Matumoto and Yoshihiko Murata received US Patent No. 4,146,402 on March 27, 1979, filed March 13, 1978.

The patent's abstract:

A process for producing a fiber-reinforced hardened body comprising mixing gypsum and slag in a ratio by weight of the former to the latter between 3:7 and 7:3 to prepare a main starting material, adding to the main starting material 1 - 30% by weight of reinforcing fiber, 0.1 - 5% by weight of alkali salt substance and 0.1 - 5% by weight of aluminum sulfate-containing substance, the respective amounts being based on the weight of the main starting material, further adding water to knead and mold the resulting starting material mixture, and curing the molded starting material mixture under normal condition or steam-curing the molded starting material mixture at 90° C. or below.

Where it was listed

• Asbestos, June 1979, in its patents department (the year's issues)