Abstract:
A GLASS SURFACE COATING COMPOSITION WHICH WHEN HEATFUSED ON A GLASS SURFACE PROVIDES THE GLASS SURFACE WITH A PROTECTIVE SCRATCH RESISTANT AND OPTICALLY TRANSPARENT COATING IN ADDITION TO PROVIDING ANTI-GLARE AND HIGH OPTICAL RESOLUTION CHARACTERISTICS. THE COATED GLASS SURFACE IS PRODUCED BY A METHOD COMPRISING THE STEPS OF HEAT-BONDING ONTO THE GLASS SURFACE AN AQUEOUS COMPOSITION CONSISTING ESSENTIALLY OF THE FOLLOWING CONSTITUENTS IN THE INDICATED RANGE OF PERCENT BY WEIGHT: CONSTITUENTS: PERCENTAGE BY WEIGHT CONSTITUENPHOSPHORIC ACID 0-30 ALUMINUM PHOSPHATE 5-14 TOGETHER WITH OTHER BENEFICIAL CONSTITUENTS IN THE FOLLOWING INDICATED RANGE OF PERCENTAGE BY WEIGHT: CONSTITUENTS: PERCENTAGE BY WEIGHT SODIUM PHOSPHATE 0-30 AMMONIUM PHOSPHATE 0-10 ANILINE PHOSPHATE 0-7 MAGNESIUM OXIDE, CARBONATE OR NITRATE 0-7 ZINC OXIDE, CARBONATE OR NITRATE 0-7 ALUMINUM HALIDE 0-7 IRON HALIDE 0-7 TOTAL OTHER BENEFICIAL CONSTITUENTS $1
Abstract:
Provided are sealing glass compositions particularly useful for sealing together alumina ceramic components in microelectronic circuitry. The sealing glass compositions are crystallizable and comprise a devitrifiable solder glass admixed with (1) a refractory material and (2) a pre-crystallized glass which together are employed in an amount sufficient to substantially reduce the time necessary to effect in situ crystallization and at the same time form a strong hermetic seal. The sealing glass compositions may be employed in any conventional form and are fired at about 400*-500* C. for about one minute to less than about 60 minutes to form a seal as described.