US3356477A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of increasing stain resistance of a glass body subjected to an ion exchange strengthening set-up
Assignee: PPG Industries Inc
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Filing: 1967-04-17
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Granted: 1967-12-05
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Expires: 1987-04-17
Abstract
No abstract record available.
Inventors
- 👤 Raymond S Chisholm
- 👤 George E Sleighter
- 👤 Fred M Ernsberger
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 23:00
CPC Classifications
C; C03; C03C; C03C21/00; C03C21/001; C03C21/002
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
87 words
A METHOD OF STRENGTHENING AN ALKALI SILICATE GLASS WHICH COMPRISES CONTACTING THE GLASS WITH A SALT OF AN ALKALI METAL HAVING A LARGER IONIC DIAMETER THAN AN ALKALI METAL IN SAID GLASS AT A TEMPERATURE BELOW THE GLASS STRAIN POINT FOR A PERIOD OF TIME SUFFICIENT TO ACHIEVE ALKALI METAL ION EXCHANGE IN AN AMOUNT SUFFICIENT TO OBTAIN A COMPRESSIVE STRESS AT THE SURFACE OF THE GLASS WHILE MAINTAINING THE ALKALINITY OF SAID SALT SUFFICIENTLY LOW TO PREVENT STAINING OF SAID GLASS WHEN SUBJECTED TO CYCLIC HUMIDITY.
Claim 2
Independent Claim
87 words
A METHOD OF STRENGTHENING AN ALKALI SILICATE GLASS WHICH COMPRISES CONTACTING THE GLASS WITH A SALT OF AN ALKALI METAL HAVING A LARGER IONIC DIAMETER THAN AN ALKALI METAL IN SAID GLASS AT A TEMPERATURE BELOW THE GLASS STRAIN POINT FOR A PERIOD OF TIME SUFFICIENT TO ACHIEVE ALKALI METAL ION EXCHANGE IN AN AMOUNT SUFFICIENT TO OBTAIN A COMPRESSIVE STRESS AT THE SURFACE OF THE GLASS WHILE MAINTAINING THE ALKALINITY OF SAID SALT SUFFICIENTLY LOW TO PREVENT STAINING OF SAID GLASS WHEN SUBJECTED TO CYCLIC HUMIDITY.
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) | 1970-12-04 | 1971-06-05 | 1971-12-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1974-12-04 | 1975-06-05 | 1975-12-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1978-12-04 | 1979-06-05 | 1979-12-05 | $7700.00 | Window Closed / Lapsed |