| 摘要 |
<p>PURPOSE:To obtain the title glass with little restriction on the content of Al2O3 and being easily controllable in the pore size by heat-treating a base glass moulding consisting of SiO2, Al2O3, B2O3, Na2O, and CaO of a specified compsn., and removing the acid-soluble component. CONSTITUTION:A raw material consisting by weight % of 45-70 SiO2 5-15 Al2O3 8-30 B2O3, 5-10 Na2O and 8-25 CaO, or 4-20 CaO+ 1.6-12.5 MgO, is calcined at ca. 1,200 deg.C, and melted then at 1,300-1,400 deg.C for 1-2hr and the product is molded to obtain a base glass molding. The, the molding is heat- treated for 2-72hr at a fixed temp. within a range between 680-800 deg.C, then dipped for 2-24hr in an acid at 50-100 deg.C to remove acid-soluble components. Thus, a porous molded product of glass consisting of 60-80 SiO2, 7-15 Al2O3, 6-12 B2O3, 3-7 Na2O, 3-7 CaO, and having cylindrical pores of 200-10,000nm pore size, and 0.3-1.2cm<3>/g pore volume, is obtd.</p> |
