| 摘要 |
804,930. Glass compositions. PITTSBURGH PLATE GLASS CO. Sept. 28, 1956 [Oct. 20, 1955], No. 29665/56. Drawings to Specification. Class 56. Colour controlling constituents of a yellowgreen glass coloured with chromium oxides, consist of 0À2 to 1 per cent. by weight of arsenic oxide, chromium oxides equivalent to 0-3 to 0À9 per cent. by weight of Cr 2 O 3 and 0À02 to 0À09 per cent. by weight of copper oxide, the ratio of Cr 2 O 3 to CuO being between 10 to 1 and 15 to 1. Suggested other components in per cent. by weight include : SiOz 70À4 to 71À4, Na2O 13À9 to 15À2, K 2 O 0À1 to 1À6, CaO 11À7 to 12À4, Na 2 SO 4 0À2 to 1À2. |
