METHOD FOR IMPROVING HEAT RESISTANCE OF E-GLASS FIBER

摘要

PURPOSE:To improve heat resistance by eluting an acid soluble component in glass fiber components in the vicinity of the fiber surface by treating an E-glass fiber with an acid aq. solution to form the high siliceous surface layer. CONSTITUTION:The high siliceous surface layer is formed by treating the E-glass fiber with the acid aq. solution to elute components such as alumina, alkaline earth metal oxide, boron oxide, alkali metal oxide or the like except silica in the vicinity of the fiber surface. The acid treatment is executed in the range that the average SiO2 content in the whole fiber after treating does not exceed 68% until the SiO2 content in the region from the fiber surface to the depth of 120Angstrom becomes =90%. As one embodiment when 9-12% hydrochloric acid is used, the heat resistance of the E-glass fiber is improved so as to tolerate the heating at 900 deg.C for =30min from 700 deg.C.