Patent ID: 7059153
Filing Date: 2006-06-13
Classification: C03B,C03C

Abstract:
1. A method for manufacturing a solid glass powder having a desired average particle size which comprises providing a mixed solution comprising (a) a raw material oxide powder comprising a glass network-forming element, said raw material powder having an average particle size which is not more than about ⅕ of said average particle size of said glass powder, and (b) an aqueous solution of a water-soluble compound comprising a different glass-forming element; identifying the amount of said raw material oxide powder based on the total of the amount of said raw material oxide powder and the amount of said water-soluble compound calculated as an oxide (oxide-converted), the melting point of said glass powder and the average particle size of the raw material oxide powder; and spray-thermal decomposing the mixed solution by application of radiant heat at a decomposition temperature which is: when the amount of said raw material oxide powder is less than about 45% by weight based on the total of the amount of said raw material oxide powder and the amount of said water-soluble compound calculated as an oxide (oxide-converted), and the average particle size of said glass powder is more than about 1/25 of the average particle size of said solid glass powder, the spray-thermal decomposition temperature is not less than the melting point of said glass powder plus about 50° C.; when the amount of said raw material oxide powder is less than about 45% by weight based on the total of the amount of said raw material oxide powder and the amount of said water-soluble compound calculated as an oxide (oxide-converted) and the average particle size of said glass powder is not more than about 1/25 of the average particle size of said solid glass powder, the spray-thermal decomposition temperature is not less than the melting point of said glass powder plus about 20° C.; when the amount of said raw material oxide powder is more than about 45% by weight based on the total of the amount of said raw material oxide powder and the oxide-converted amount of said water-soluble compound, and the raw material oxide powder has an average particle size which is more than about 1/25 of the average particle size of said glass powder, the spray-thermal decomposition temperature is not less than the melting point of said glass powder plus about 30° C.; and when the amount of said raw material oxide powder is more than about 45% by weight based on the total of the amount of said raw material oxide powder and the oxide-converted amount of said water-soluble compound, and the raw material oxide powder has an average particle size which is not more than about 1/25 of the average particle size of said glass powder, the spray-thermal decomposition temperature is not less than the melting point of said glass powder.