Patent US3573076A successfully refreshed from Google Patents.
US3573076A
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US
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Glass-ceramic article and method
Assignee: Corning Glass Works
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Filing: 1969-03-03
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Granted: 1971-03-30
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Expires: 1989-03-03
Abstract
Abstract THIS INVENTION RELATES TO THE STRENGTHENING OF GLASS CERAMIC ARTICLES WHEREN THE CRYSTAL CONTENT THEREOF COMPRISES THE PREDOMINANT PORTION AND CONTAINING BETA-QUARTZ STUFFED WITH LITHIUM AND MAGENSIUM IONS AS THE PRINCIPAL CRYSTAL PHASE. THE STRENGTHENING EFFECT IS ACHIEVED THROUGH AN ION EXCHANGE PROCESS TAKING PLACE WITHIN A SURFACE LAYER OF THE GLASS-CERAMIC ARTICLE WHEREIN POTASSIUM IONS FROM AN EXTERNAL SOURCE ARE EXCHANGE DFOR LITHIUM IONS IN THE BETA-QUARTZ, BUT WHEREIN THE STRUCTURAL NATURE OF THE CRYSTALS REMAIN ESSENTIALLY UNCHANGED, TO CAUSE COMPRESSIVE STRESSES TO BE DEVELOPED IN THIS SURFACE LAYER.
Inventors
- 👤 Hermann L Rittler
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 17:03
CPC Classifications
C; C03; C03B; C03B23/00; C03B23/04; C03B23/08; C03B23/09; C03B23/095; C03C; C03C10/00; C03C10/0018; C03C10/0027; C03C10/0036; C03C10/0045; C03C21/00; C03C21/001; C03C21/002
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) | 1974-03-29 | 1974-09-28 | 1975-03-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-03-29 | 1978-09-28 | 1979-03-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-03-29 | 1982-09-28 | 1983-03-30 | $7700.00 | Window Closed / Lapsed |