Patent US2777255A successfully refreshed from Google Patents.
US2777255A
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Method for producing improved monocrystalline refractive material
Assignee: NL Industries Inc
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Filing: 1953-02-02
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Granted: 1957-01-15
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Expires: 1973-02-02
Abstract
No abstract record available.
Inventors
- 👤 Merker Leon
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 17:17
CPC Classifications
C; C04; C04B; C04B35/00; C04B35/51; C04B35/01; C04B35/46; C04B35/48; C04B35/50; C30; C30B; C30B29/00; C30B29/10; C30B29/16; C30B29/22; C30B29/26; Y; Y10; Y10S; Y10S117/00; Y10S117/918
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
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US1436164A
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US1298540A
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GB243251A
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FR662782A
Cited
CH252698A
Cited
GB608453A
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US2507253A
Cited
GB664889A
Cited
US2610129A
Cited
US2628156A
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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 |