Ivory color in opaque glass-ceramic
AssigneeCorning Incorporated
InventorRobert W. Pfitzenmaier
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Abstract
An ivory-colored, opaque glass-ceramic having a beta-spodumene solid solution as its primary crystal phase, and a method of controlling color in the glass-ceramic. The glass-ceramic is produced from a Li.sub.2 O--Al.sub.2 O.sub.3 --SiO.sub.2 precursor glass containing 3-6% TiO.sub.2 +ZrO.sub.2 as a nucleating agent and having colorants controlled at levels of up to 20 ppm Co.sub.3 O.sub.4, up to 1000 ppm Fe.sub.2 O.sub.3 and 1000-2000 ppm CeO.sub.2.
Claims9
An ivory-colored, opaque, Li.sub.2 O--Al.sub.2 O.sub.3 --SiO.sub.2 glass-ceramic having beta-spodumene as its primary crystal phase, having a CeO.sub.2 content of 1000-2000 ppm, and having color coordinates, based on the CIE system (Illuminant C) of x=0.3100-0.3200, y=0.3180-0.3270 and Y=65-90.
A method of producing an ivory color in a glass-ceramic material having beta-spodumene solid solution as its predominant crystal phase, the method comprising melting a mixture of raw materials containing between 1000 ppm and 2000 ppm of CeO.sub.2 in the precursor glass, forming an article from the glass, cooling the glass below its transformation range, and subsequently crystallizing the glass article by a thermal treatment step.
Dependencies are inferred from the claim text.