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US2681344A
Expired / Lapsed
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Coloring matters of the tetra-aza porphin series
Assignee: Imperial Chemical Industries Ltd
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Filing: 1951-01-03
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Granted: 1954-06-15
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Expires: 1971-01-03
Abstract
No abstract record available.
Inventors
- 👤 France Harold
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 21:46
CPC Classifications
C; C09; C09B; C09B47/00; C09B47/04; C09B47/06; C09B47/067
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
11 words
AS COLORING MATTERS, METAL-CONTAINING AND METAL-FREE TETRA-AZA-PORPHIN DERIVATIVES OF THE FORMULA:
Claim 2
Dependent Claim
11 words
AS COLORING MATTERS, METAL-CONTAINING AND METAL-FREE TETRA-AZA-PORPHIN DERIVATIVES OF THE FORMULA:
References Cited (Backward Citations)
CH215404A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1957-06-14 | 1957-12-14 | 1958-06-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1961-06-14 | 1961-12-14 | 1962-06-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1965-06-14 | 1965-12-14 | 1966-06-15 | $7700.00 | Window Closed / Lapsed |