Patent ID: 6492288
Filing Date: 2002-12-10
Classification: C03C

Abstract:
A glass ceramic comprising a main crystal phase which comprises at least one selected from a group consisting of &bgr;-eucryptite (&bgr;-Li2O.Al2O3.2SiO2), &bgr;-eucryptite solid solution (&bgr;-Li2O.Al2O3.2SiO2 solid solution), &bgr;-quartz (&bgr;-SiO2), and &bgr;-quartz solid solution (&bgr;-SiO2 solid solution),wherein an average grain size of the main crystal phase is less than 5 &mgr;m, and a coefficient of thermal expansion thereof is âˆ’30Ã—10âˆ’7 to âˆ’90Ã—10âˆ’7/Â° C. in a temperature range of âˆ’40Â° C. to +160Â° C., and a hysteresis of the coefficient of thermal expansion is not more than 20 ppm.