| 摘要 |
PURPOSE:To impart water resistance to a hollow silicate with a simple procedure by incorporating water into a hollow body of silicate contg. salts which are eluted with water with a specified degree of elution. CONSTITUTION:7-12% water is incorporated into a hollow silicate body which is eluted with water to eliminate its salts contained therein by 0.3-1.2% when 3g hollow silicate body is charged in 200cc water at 60 deg.C and stirred for 1hr at 80rpm. The compsn. of the hollow silicate body consists for example of SiO2, Na2O, B2O3, K2O, Al2O3, etc., and the hollow body is prepd. by, for example, spray-drying soln. of silicate contg. boric acid and heat treating obtd. powder to obtain a hollow body, etc. To control the degree of elution of the hollow silicate body to the above described value, a silane compd. expressed by the formula (R is H, CH3, CH2=CH2, etc.; X is Cl, OR, etc.) is sprayed on the hollow body or allowed to contact in the gaseous state, and then heat-treated at 200-300 deg.C. |
