Process for producing glass material granules and process for producing glass product

摘要

To provide a process for producing glass raw material granules which are less likely to be formed into fine powders which cause a change of the glass composition at a time of forming a glass melt or defects of glass, and which can be preferably used for producing glass.;A process for producing glass raw material granules, which comprises a granulation step of adding boric acid to either one of or both of a glass raw material powder and an alkaline solution having a pH of at least 9 and mixing the glass raw material powder together with the alkaline solution. The glass raw material powder preferably contains at least 10 mass % of boric acid.

主权项

1. A process for producing glass raw material granules, comprising:
adding boric acid to at least one of or a glass raw material powder and an alkaline solution having a pH of at least 9; and mixing the glass raw material powder together with the alkaline solution after the addition of boric acid to obtain a glass raw material powder mixture; and granulating the glass raw material powder mixture to form the glass raw material granules; wherein the mixing and granulating are conducted by tumbling granulation; wherein the glass raw material powder is a borosilicate glass, comprising as represented by mass percentage based on oxides SiO2: from 40 to 85 mass %, Al2O3: from 1 to 22 mass %, B2O3: from 2 to 20 mass %, MgO: from 0 to 8 mass %, CaO: from 0 to 14.5 mass %, SrO: from 0 to 24 mass %, BaO: from 0 to 30 mass %, and R2O: from 0 to 10 mass % wherein R is an alkali metal.