| 摘要 |
PURPOSE:To obtain the title low-viscosity glass having chemical durability while maintaining desired refractive index and coefficient of expansion, containing SiO2, B2O3, Al2O3, CaO+MgO, PbO, ZnO, BaO+SrO, Li2O, Na2O+K2 O, As2O3+Sb2O3 and F so as to give a specific composition. CONSTITUTION:Raw material compounds are blended so as to contain 60-74wt.% SiO2, 0-10wt.% B2O3, 0-8wt.% Al2O3, 0-12wt.% CaO+MgO, 3-15wt.% PbO, 0-10wt.% ZnO, 6-15wt.% PbO+ZnO, 0-5wt.% BaO+SrO, 0.2-7wt.% Li2O, 5-20wt.% Na2O+K2O, 0-1wt.% As2O3+Sb2O3 and 0-5wt.% F and the blend is used as a starting raw material and made into glass. |
