Patent ID: 7169476

Claim:
A zinc oxide-alumina-silica-based crystallized glass comprising a main component comprising zinc oxide (ZnO), alumina (Al 2 O 3 ) and silica (SiO 2 ); a nucleating agent comprising ZrO 2 ; and a modification component; wherein the main component comprises 20–30% by mass of zinc oxide, 15–25% by mass of alumina and 50–60% by mass of silica and amounts to 100% by mass in total; wherein the nucleating agent comprises 3–6 parts by mass of ZrO 2 based on 100 parts by mass of the main component; and wherein the modification component comprises at least one of niobium oxide (Nb 2 O 5 ) and tantalum oxide (Ta 2 O 5 ) in an amount of 0.1–0.05 parts by mass based on 100 parts by mass of the main component.