US4059457A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Chitin solution
Assignee: University of Delaware
•
Filing: 1976-09-30
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Granted: 1977-11-22
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Expires: 1996-09-30
Abstract
Abstract Solutions of chitin in dimethylacetamide, N-methylpyrrolidone or mixtures of these in combination with a minor proportion of lithium chloride.
Inventors
- 👤 Paul Rolland Austin
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 10:09
CPC Classifications
C; C08; C08L; C08L5/00; C08L5/08; C08B; C08B37/00; C08B37/0006; C08B37/0024; C08B37/0027; C08B37/003
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
22 words
A solution of chitin in dimethylacetamide or N-methylpyrrolidone or mixtures of these amides in conjunction with a minor amount of lithium chloride.
Claim 2
Dependent Claim
22 words
A solution of chitin in dimethylacetamide or N-methylpyrrolidone or mixtures of these amides in conjunction with a minor amount of lithium chloride.
Claim 3
Dependent Claim
24 words
The solution of claim 1 wherein the lithium chloride is present in the solution in an amount of at least 2% of the solvent.
Claim 4
Dependent Claim
29 words
The solution of claim 1 which has been held until the chitin which in solution originally, if it had dextro optical rotation, is converted to the levo rotatory form.
References Cited (Backward Citations)
US3068188A
Cited
US3892731A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-11-21 | 1981-05-23 | 1981-11-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-11-21 | 1985-05-23 | 1985-11-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-11-21 | 1989-05-23 | 1989-11-22 | $7700.00 | Window Closed / Lapsed |