IMPROVEMENT OF HEAT RESISTANCE OF CERAMIC FIBER AND CERAMIC FIBER-CONTAINING HEAT INSULATOR

摘要

PURPOSE: To improve the heat resistance of amorphous aluminosilicate ceramic fibers by fixing specified amts. of a water-soluble boron compd. and a water-soluble phosphorus compd. forming B2 O3 and P2 O5 , respectively by heating them in air on the surfaces of the ceramic fibers. CONSTITUTION: An aq. soln. contg. a water-soluble boron compd. (e.g. boric acid) and a water-soluble phosphorus compd. (e.g. triammonium phosphate) forming B2 O3 and P2 O5 , respectively at =900 deg.C when heated in air is prepd. and stuck to the surfaces of amorphous aluminosilicate ceramic fibers, and then the boron and phosphorus compds. are fixed on the surface of the fiber by drying. At this time, the boron and phosphorus compds. are stuck on the surface of the fiber by 0.1-5wt.% (expressed in terms of B2 O3 and P2 O5 ) in total of boron and phosphorus compds. (based on the wt.) of the fiber so that the molar ratio of B2 O3 to (B2 O3 +P2 O5 ) is regulated to 0.1-0.5 by regulating the concns. of the boron and phosphorus compds. in the aq. soln. contg. and the coating weight of the soln. on the surface of the fiber and ceramic fiber excellent in heat resistance and fit for a heat insulator are obtd.