Patent US2777774A successfully refreshed from Google Patents.
US2777774A
Expired / Lapsed
US
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Optical glass
Assignee: Ernst Leitz Wetzlar GmbH
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Filing: 1953-01-21
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Granted: 1957-01-15
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Expires: 1973-01-21
Abstract
No abstract record available.
Inventors
- 👤 Weissenberg Gustav
- 👤 Meinert Norbert
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 15:46
CPC Classifications
C; C03; C03C; C03C3/00; C03C3/12; C03C3/16; C03C3/19; C03C3/21; Y; Y10; Y10S; Y10S501/00; Y10S501/90; Y10S501/903
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
82 words
OPTICAL CROWNS GLASS THE GLASS FORMING CONSTITUENTS OF WHICH CONSIST ESSENTIALLY OF AT LEAST ONE METAPHOSPHATE OF THE GROUP CONSISTING OF MAGNESIUM, CALCIUM, STRONITUM AND BARIUM, BORON TRIOXIDE AND AT LEAST OEN CARBONATE OF THE GROUP CONSISTING OF MAGNESIUM, CLCIUM, STRONTIUM, BARIUM AND LITHIUM AND BEING THE HEAT REACTION PRODUCT OF A BATCH HAVING FROM 57% TO 86% BY WEIGHT OF SAID METAPHOSPHATE AND FROM ABOUT 8.6% TO ABOUT 12.6% OF BORON TRIOXIDE AND FROM 0.9% TO 34.4% OF SAID CARBONATE GROUP.
Claim 2
Dependent Claim
82 words
OPTICAL CROWNS GLASS THE GLASS FORMING CONSTITUENTS OF WHICH CONSIST ESSENTIALLY OF AT LEAST ONE METAPHOSPHATE OF THE GROUP CONSISTING OF MAGNESIUM, CALCIUM, STRONITUM AND BARIUM, BORON TRIOXIDE AND AT LEAST OEN CARBONATE OF THE GROUP CONSISTING OF MAGNESIUM, CLCIUM, STRONTIUM, BARIUM AND LITHIUM AND BEING THE HEAT REACTION PRODUCT OF A BATCH HAVING FROM 57% TO 86% BY WEIGHT OF SAID METAPHOSPHATE AND FROM ABOUT 8.6% TO ABOUT 12.6% OF BORON TRIOXIDE AND FROM 0.9% TO 34.4% OF SAID CARBONATE GROUP.
References Cited (Backward Citations)
US2294844A
Cited
US2278501A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1960-01-15 | 1960-07-16 | 1961-01-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1964-01-15 | 1964-07-16 | 1965-01-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1968-01-15 | 1968-07-16 | 1969-01-15 | $7700.00 | Window Closed / Lapsed |