Thermal Cleaning of Glass-Ceramic Powders and Achieving a White Sample After Sintering in an Inert Atmosphere
Original Publication Date: 1984-Oct-01
Included in the Prior Art Database: 2005-Feb-05
This article describes a thermal cleaning process for glass powders that does not affect their physical properties but prevents the formation of an undesired dark grey color in fired glass-ceramic. Glass powders being used in MLC (multilayer ceramic) and thin film substrates are prepared by ball-milling glass-ceramic cullets in a methanol grinding medium. When such powders are later sintered under an inert atmosphere at elevated temperatures, dark grey colored samples have been observed to result, due probably to unwanted carbonaceous residues associated with the methanol used in the ball-milling process. The thermal cleaning process here disclosed is imposed immediately following normal ball-milling and drying operations.