Patent US2764492A successfully refreshed from Google Patents.
US2764492A
Expired / Lapsed
US
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Borate optical glass
Assignee: Ernst Leitz Wetzlar GmbH
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Filing: 1951-06-12
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Granted: 1956-09-25
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Expires: 1971-06-12
Abstract
No abstract record available.
Inventors
- 👤 Weissenberg Gustav
- 👤 Ungemach Otto
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 05:33
CPC Classifications
C; C03; C03C; C03C3/00; C03C3/04; C03C3/062; C03C3/07; C03C3/072; C03C3/12; C03C3/23; Y; Y10; Y10S; Y10S501/00; Y10S501/90; Y10S501/901; Y10S501/903
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
96 words
OPTICAL GLASS CONSISTING ESSENTIALLY OF BORIC ACID ANHYDRIDE, AT LEAST ONE FLUORIDE OF AN ELEMENT OF THE GROUP CONSISTING OF LITHIUM, MAGNESIUM, CALCIUM, STRONTIUM, BARIUM, ZINC, CADMIUM AND MERCURY AND AT LEAST ONE OXIDE OF AN ELEMENT OF THE GROUP CONSISTING OF LITHIUM, MAGNESIUM, CALCIUM, STRONTIUM, ZINC, BARIUM, CADMIUM AND MERCURY, IN WHICH THE MOL PROPORTION OF BORIC ACID ANHYDRIDE TO THE FLUORIDES LIES BETWEEN 10:1 AND 1:1 AND THE BORIC ACID ANHYDRIDE AND FLUORIDES TOGETHER ARE BETWEEN 8.3 BY WEIGHT AND 91% BY WEIGHT OF THE GLASS THE BALANCE BEING OXIDES OF THE ABOVE GROUP.
Claim 2
Dependent Claim
96 words
OPTICAL GLASS CONSISTING ESSENTIALLY OF BORIC ACID ANHYDRIDE, AT LEAST ONE FLUORIDE OF AN ELEMENT OF THE GROUP CONSISTING OF LITHIUM, MAGNESIUM, CALCIUM, STRONTIUM, BARIUM, ZINC, CADMIUM AND MERCURY AND AT LEAST ONE OXIDE OF AN ELEMENT OF THE GROUP CONSISTING OF LITHIUM, MAGNESIUM, CALCIUM, STRONTIUM, ZINC, BARIUM, CADMIUM AND MERCURY, IN WHICH THE MOL PROPORTION OF BORIC ACID ANHYDRIDE TO THE FLUORIDES LIES BETWEEN 10:1 AND 1:1 AND THE BORIC ACID ANHYDRIDE AND FLUORIDES TOGETHER ARE BETWEEN 8.3 BY WEIGHT AND 91% BY WEIGHT OF THE GLASS THE BALANCE BEING OXIDES OF THE ABOVE GROUP.
References Cited (Backward Citations)
GB190708704A
Cited
US1529259A
Cited
GB462304A
Cited
DE694213C
Cited
US2420644A
Cited
US2578325A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1959-09-25 | 1960-03-26 | 1960-09-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1963-09-25 | 1964-03-26 | 1964-09-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1967-09-25 | 1968-03-26 | 1968-09-25 | $7700.00 | Window Closed / Lapsed |