US Patent 7902097 Neutral gray glass composition

The present invention is to provide a neutral gray colored glass composition that has a soda-lime-silica glass base composition containing as major colorants 0.30 to 0.70% by weight Fe2O3; 0 to 30 ppm of Co3O4; 1 to 20 ppm of Se; and 20 to 200 ppm of CuO. The glass provides an illuminant “A” light transmission greater of 65%, a total solar energy transmittance of less than or equal to 60%, a solar ultraviolet transmittance of less than 46%; a dominant wavelength from 490 nm to 600; and an excitation purity of less than 6.