| 摘要 |
PROBLEM TO BE SOLVED: To obtain glass excellent in mechanical strength and surface smoothness after polishing by consisting of a principal component provided with CaO, Al2 O3 and SiO2 in a specified ratio expressed in terms of the oxides and an arbitrary specified component. SOLUTION: This glass comprises, on the basis of weight expressed in terms of the oxides, 100 parts principal component consisting of CaO, Al2 O3 and SiO2 in a ratio of about 2:1:2 and 0-15 parts one or more components selected from among 0-10 parts MgO, 0-10 parts BaO, 0-10 parts SrO, 0-10 parts ZnO, 0-10 parts TiO2 , 0-15 parts ZrO2 , 0-10 parts Y2 O3 , 0-10 parts La2 O3 , 0-5 parts As2 O3 + Sb2 O3 , 0-10 parts Fe2 O3 , 0-10 parts Cr2 O3 , 0-10 parts NiO, 0-10 parts V2 O5 , 0-10 parts CuO, 0-10 parts Ag2 O 0-10 parts MnO2 and 0-10 parts MoO3 (where, 0 parts <=Fe2 O3 +Cr2 O3 +NiO+V2 O5 +CuO+Ag2 O+MnO2 +MoO3 <=10 parts). |
