Luminous glass ceramics
AssigneeKabushiki Kaisha Ohara
InventorsKazuo {overscore (O)}hara, Satoru Matsumoto, Naoyuki Goto
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Abstract
A luminous glass ceramic comprising a main crystallized phase of spinel or a solid solution of spinel including the components in weight %: SiO2 30-65 Al2O3 5-35 MgO 1-20 BaO 3-4 ZnO 5-35 TiO2 1-15 As2O3 + Sb2O3 0-3 wherein one or more rare earth elements are added to the glass ceramic in an amount of 0.1-30 wt %.
Claims9
A luminous glass ceramic, comprising:
- a main crystallized phase selected from the group consisting of spinel and solid solution of spinel;
- and
- at least one rare earth element in a phase selected from the group consisting of a glass phase, a crystallized phase and mixtures thereof;
- wherein the luminous glass ceramic having a thermal shock resistance |Δt|° C. of not less than 150, the thermal shock resistance |Δt| is obtained by following equation, |Δt|=(flexural strength)×(1−(Poisson's ratio))/((coefficient of thermal expansion)×(Young's modulus)).
The luminous glass ceramic as claimed in 1, wherein a grain size of a deposited crystal in the luminous glass ceramic is less than 300 Å, and the luminous glass ceramic has a coefficient of thermal expansion of 25×10−7 to 85×10−7/° C. in the temperature range of −60° C. to +160° C.
Dependencies are inferred from the claim text.