Sol-gel process of making glass, particulary gradient-index glass
US5308802A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jun 25, 1993 |
| Grant date | May 3, 1994 |
| Priority date | — |
| Expiry date | Jun 25, 2013 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC03C1/006
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
The present invention relates to a process for making glass by the sol-gel process. A mixture of silicon alkoxide, at least two other metal alkoxides, and alcohol in a solution sufficiently acidic to hydrolyze partially the silicon alkoxide is formed. Water is then added under agitation to convert the metal alkoxides to a network of corresponding metal oxides suitable for gelation. The mixture containing the network of metal oxides is then molded for a sufficient time to form a gel. Substantially only oxides of one of the at least two other metals is then removed from the gel, which is then fixed in a liquid capable of arresting such additional removal. The fixed gel is then dried and sintered to form a glass. The step of removing the at least one other metal oxide from the gel can be followed with a step of withdrawing partially oxides of one of the remaining at least two other metals in order to form a transparent gradient-index glass after sintering.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.