Patent ID: 6274523
Filing Date: 2001-08-14
Classification: C03C

Abstract:
A neutral gray colored glass composition having a base glass portion comprising:SiO.sub.2 66 to 75 percent by weight Na.sub.2 O 10 to 20 percent by weight CaO 5 to 15 percent by weight MgO 0 to 5 percent by weight Al.sub.2 O.sub.3 0 to 5 percent by weight K.sub.2 O 0 to 5 percent by weightand a colorant portion consisting essentially of:Fe.sub.2 O.sub.3 (total iron) 0.6 to 1.1 percent by weight FeO up to 0.30 percent by weight CoO 60 to 180 PPM Se 10 to 30 PPM NiO 25 to 550 PPMthe glass having a luminous transmittance of 20 to 44.5 percent at a thickness of 3.9 millimeters.