Patent US3228760A successfully refreshed from Google Patents.
US3228760A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of tempering by heat treating vitreous silica
Assignee: Thermal Syndicate Ltd
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Filing: 1962-08-24
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Granted: 1966-01-11
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Expires: 1982-08-24
Abstract
No abstract record available.
Inventors
- 👤 Jack Kenneth Henderson
- 👤 Winterburn John Alexander
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 10:27
CPC Classifications
C; C03; C03B; C03B25/00; C03B25/02; C03B32/00
Claims Analysis
Total Claims: 1
Claim 1
Independent Claim
100 words
IN A PROCESS OF ANNEALING VITREOUS SILICA, THE METHOD OF STRESSING A BODY OF VITREOUS SILICA, COMPRISING THE STEPS OF DETERMINING THE WATER CONTENT OF SAID BODY OF VITREOUS SILICA; SUBJECTING SAID BODY OF VITREOUS SILICA TO ANNEALING WITHIN AN ELEVATED TEMPERATURE RANGE OF BETWEEN 850* C. AND 1000*C. AND THREAFTER TO COOLING TO A SUBSTANTIALLY LOWER TEMPERATURE; AND SIMULTANEOUSLY CONTROLLING THE WATER CONTENT OF THE AMBIENT ATMOSPHERE SO THAT THE PARTIAL WATER VAPOR PRESSURE INSAID AMBIENT ATMOSPHERE IS GREATER THAN THAT REQUIRED FOR EQUILIBRIUM, AT SAID ELEVATED TEMPERATURE, WITH SAID DETERMINED WATER CONTENT OF SAID BODY OF VITREOUS SILICA.
References Cited (Backward Citations)
US176066A
Cited
US2982053A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1969-01-10 | 1969-07-12 | 1970-01-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1973-01-10 | 1973-07-12 | 1974-01-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1977-01-10 | 1977-07-12 | 1978-01-11 | $7700.00 | Window Closed / Lapsed |