US2528634A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Ophthalmic glass
Assignee: Corning Glass Works
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Filing: 1949-09-16
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Granted: 1950-11-07
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Expires: 1969-09-16
Abstract
No abstract record available.
Inventors
- 👤 William H Armistead
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 10:04
CPC Classifications
C; C03; C03C; C03C3/00; C03C3/04; C03C3/076; C03C3/102; C03C3/105; Y; Y10; Y10S; Y10S501/00; Y10S501/90; Y10S501/903
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
128 words
A GLASS COMPRISING ESSENTIALLY 32% TO 48% SIO2, AT LEAST ONE ALKALI METAL OXIDE IN THE INDICATED PROPORTION SELECTED FROM THE GROUP CONSISTING OF UP TO 11% K2O, UP TO 11% NA2O, AND UP TO 2% LI2O, THE SELECTED ALKALI METAL OXIDE INCLUDING AN OXIDE SELECTED FROM THE GROUP CONSISTING OF K2O AND NA2O IN THE ABOVE-INDICATED PROPORTION, THE TOTAL ALKALI METAL OXIDE BEING BETWEEN 6.5% AND 11%, 36% TO 54% PBO, 0.5% TO 4% AL2O3, AND 0.5% TO 7% ZRO2, THE TOTAL AL2O3 AND ZRO2 BEING 2.5% TO 10% THE TOTAL OF THE ESSENTIAL CONSTITUENTS BEING AT LEAST 92%, THE INDEX OF REFRACTION (ND) BEING 1.61 TO 1.71 AND THE THERMAL EXPANSION COEFFICIENT BEING BETWEEN 84X10-7 AND 91X10-7 CM. PER CM. PER *C. BETWEEN 0* AND 300*C.
Claim 2
Dependent Claim
128 words
A GLASS COMPRISING ESSENTIALLY 32% TO 48% SIO2, AT LEAST ONE ALKALI METAL OXIDE IN THE INDICATED PROPORTION SELECTED FROM THE GROUP CONSISTING OF UP TO 11% K2O, UP TO 11% NA2O, AND UP TO 2% LI2O, THE SELECTED ALKALI METAL OXIDE INCLUDING AN OXIDE SELECTED FROM THE GROUP CONSISTING OF K2O AND NA2O IN THE ABOVE-INDICATED PROPORTION, THE TOTAL ALKALI METAL OXIDE BEING BETWEEN 6.5% AND 11%, 36% TO 54% PBO, 0.5% TO 4% AL2O3, AND 0.5% TO 7% ZRO2, THE TOTAL AL2O3 AND ZRO2 BEING 2.5% TO 10% THE TOTAL OF THE ESSENTIAL CONSTITUENTS BEING AT LEAST 92%, THE INDEX OF REFRACTION (ND) BEING 1.61 TO 1.71 AND THE THERMAL EXPANSION COEFFICIENT BEING BETWEEN 84X10-7 AND 91X10-7 CM. PER CM. PER *C. BETWEEN 0* AND 300*C.
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) | 1953-11-06 | 1954-05-08 | 1954-11-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1957-11-06 | 1958-05-08 | 1958-11-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1961-11-06 | 1962-05-08 | 1962-11-07 | $7700.00 | Window Closed / Lapsed |