Patent ID: 7071132
Filing Date: 2006-07-04
Classification: C03C,G02B

Abstract:
1. Low expansion transparent glass-ceramics obtained by heat treating a base glass containing 3–15% ZnO in mass % based on the total amount of oxides present and which is produced at a melting temperature of 1530° C. or below, said glass-ceramics containing β-quartz or β-quartz solid solution as a predominant crystal phase and 50%–60% SiO 2 in mass % on the basis of amount of total oxides, being free of K 2 O and Na 2 O, having an average linear thermal expansion coefficient (α) within a range from +6×10 −7 /° C. to +35×10 −7 /° C. within a temperature range from 100° C. to 300° C. and having 80% transmittance wavelength (T 80 ) of 700nm or below.