| 摘要 |
PURPOSE:To produce a glass body having a large area in spite of a large thickness by adding a specified amt. of ethylene glycol to sol when bulky glass is produced by a sol-gel process. CONSTITUTION:When glass is produced by a sol-gel process with at least alkyl silicate and fine silica powder as starting materials, 0.1-5 times (mol) as much ethylene glycol as the alkyl silicate is added to sol. The added ethylene glycol forms a chelate, makes a reaction moderate and reduces strain in gel. Accordingly, stress as the cause of cracking is reduced, the gel is hardly cracked and a thick large-sized quartz glass block is obtd. |
