| 摘要 |
An infra red and ultra violet soda-lime-silica glass of a neutral tint (as defined in the specification) containing 0.25% to 1.75% by weight total iron expressed as Fe2O3 and a ferrous content by weight calculated from the equation: <IMAGE> the glass further including one or more colourants selected from Se, Co3O4, Nd2O3, NiO, V2O5, CeO2, TiO2, CuO, MnO and SnO such that the glass, in a 4 mm thickness has a visible light transmission of at least 32%, a direct solar heat transmission at least seven percentage points lower than the visible light transmission and an ultra violet transmission of less than 25%. When Se is present at least one of the specified further oxides is present in an amount at least 1.5 times that of the Se. The dominant wavelength is preferably below 570 nm; if higher, the colour purity is below 4 when the visible light transmission exceeds 60%. |
