US3756798A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Of making same novel glass ceramic article and water content crystallization process
Assignee: PPG Industries Inc
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Filing: 1971-03-16
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Granted: 1973-09-04
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Expires: 1991-03-16
Abstract
Abstract NOVEL GLASS-CERAMIC ARTICLES OF SUPERIOR STRENGTH AND SUPERIOR THERMAL STABILITY ARE CHARACTERIZED AS HAVING SURFACE ZONES IN COMPRESSION, INTERIOR ZONES IN TENSION AND BEING COMPRISED OF RANDOMLY-ORIENTED CRYSTALS OF SUBSTANTIALLY UNIFORM COMPOSITION DISPOSED SUBSTANTIALLY UNIFORMLY THROUGHOUT. SUCH ARTICLES ARE PRODUCED BY CONTROL LING THE RELATIVE RATES OF CRYSTALLIZATION AT THE SURFACE AND IN THE INTERIOR OF GLASS-CERAMIC BY CONTROLLING THE RELATIVE WATER CONTENT AT THE SURFACE AND IN THE INTERIOR OF THE GLASS-CERAMIC DURING NUCLEATION AND CRYSTALLIZATION.
Inventors
- 👤 F Ernsberger
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 14:03
CPC Classifications
C; C03; C03C; C03C10/00; C03C10/0018; C03C10/0027
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-09-03 | 1977-03-05 | 1977-09-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-09-03 | 1981-03-05 | 1981-09-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-09-03 | 1985-03-05 | 1985-09-04 | $7700.00 | Window Closed / Lapsed |