PRODUCTION OF CELLULOSE FIBER REINFORCED GYPSUM BOARD

摘要

PURPOSE:To enable remarkable improvement in the machine screw retention power of a gypsum board obtd. by using a slurry prepd. by adding specific cellulose fibers to calcined gypsum. CONSTITUTION:The slurry prepd. by the following method A or B is poured between the sheets of the raw paper of the gypsum board and is cured. The cellulose fibers which are in a 100-650ml range of the Canadian standard freeness specified in JIS (Japanese Industrial Standards) P 8121 are added in the form of dry cellulose fibers at 1.5-6.0pts.wt. to (A) 100pts.wt. calcined gypsum and are mixed dry; thereafter, water is added and mixed to and with the mixture. The above-mentioned cellulose fibers are then dispersed as (B) dry cellulose fibers at 1.5-6.0pts.wt. in water and 100pts.wt. calcined gypsum are added and mixed to and with thereto. The kinds of the cellulose fibers are not particularly limited.