US5008219A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for producing glass
Assignee: Hoya Corp
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Filing: 1989-12-11
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Granted: 1991-04-16
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Expires: 2009-12-11
Abstract
Abstract The present invention relates to a sol-gel glass producing process which comprises hydrolyzing a metal alkoxide in the presence of an organic solvent and an aqueous ammonia solution to obtain a sol solution, concentrating the sol solution to 1.00-1.95 times the volume of the metal alkoxide used, adding an acid catalyst to the resulting concentrate to allow the concentrate to gel, drying the resulting gel, and heating the dried gel to obtain a desired glass. According to the present invention, a large sized glass can be obtained without the formation of cracks.
Inventors
- 👤 Koichi A. Hara
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 05:53
CPC Classifications
C; C03; C03B; C03B19/00; C03B19/12; C03C; C03C1/00; C03C1/006; Y; Y10; Y10S; Y10S65/00; Y10S65/901
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
89 words
A process for producing a glass, comprising: (a) hydrolyzing a metal alkoxide selected from the group consisting of silicon, aluminum, titanium and zirconium in the presence of an organic solvent and an aqueous ammonia solution to obtain a sol solution, (b) concentrating the sol solution to 1.00-1.95 times the volume of the metal alkoxide used, (c) adding a hydrofluoric or hydrosilicofluoric acid catalyst to the resulting concentrate to allow the concentrate to gel, (d) drying the resulting gel, and (e) heating the dried gel to obtain the desired glass.
Claim 2
Dependent Claim
89 words
A process for producing a glass, comprising: (a) hydrolyzing a metal alkoxide selected from the group consisting of silicon, aluminum, titanium and zirconium in the presence of an organic solvent and an aqueous ammonia solution to obtain a sol solution, (b) concentrating the sol solution to 1.00-1.95 times the volume of the metal alkoxide used, (c) adding a hydrofluoric or hydrosilicofluoric acid catalyst to the resulting concentrate to allow the concentrate to gel, (d) drying the resulting gel, and (e) heating the dried gel to obtain the desired glass.
Claim 3
Dependent Claim
17 words
A process according to claim 1, wherein a metal salt is used together with the metal alkozide.
Claim 4
Dependent Claim
29 words
A process according to claim 1, wherein the concentration is effected by heating the sol solution to be concentrated while feeding air above the surface of the sol solution.
Claim 5
Dependent Claim
17 words
A process according to claim 3, wherein the concentration is effected in a hot air circulating oven.
References Cited (Backward Citations)
US4681615A
Cited
JPH09102833A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1994-04-15 | 1994-10-15 | 1995-04-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-04-15 | 1998-10-15 | 1999-04-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-04-15 | 2002-10-15 | 2003-04-16 | $7700.00 | Window Closed / Lapsed |