US2801231A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Preparation of linear polyurethanes from alkyl diurethanes of aromatic diamines
Assignee: Eastman Kodak Co
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Filing: 1954-08-10
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Granted: 1957-07-30
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Expires: 1974-08-10
Abstract
No abstract record available.
Inventors
- 👤 John R Caldwell
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 17:20
CPC Classifications
C; C08; C08G; C08G71/00; C08G71/04; C08G18/00; C08G18/06; C08G18/28; C08G18/30; C08G18/32; C08G18/3203; C08G18/3206; C08G18/70; C08G18/701
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
39 words
THE METHOD OF MAKING A LINEAR POLYURETHANE BY DIRECT ESTER-INTERCHANGE BETWEEN AN A,W-GLYCOL AND AN ALKYL DIURETHANE OF AN AROMATIC DIAMINE WHICH COMPRISES HEATING A MIXTURE OF A BIFUNCTIONAL ALKYL DIRETHANE OF AN AROMATIC DIAMINE CHARACTERIZED BY THE STRUCTURE
Claim 2
Independent Claim
39 words
THE METHOD OF MAKING A LINEAR POLYURETHANE BY DIRECT ESTER-INTERCHANGE BETWEEN AN A,W-GLYCOL AND AN ALKYL DIURETHANE OF AN AROMATIC DIAMINE WHICH COMPRISES HEATING A MIXTURE OF A BIFUNCTIONAL ALKYL DIRETHANE OF AN AROMATIC DIAMINE CHARACTERIZED BY THE STRUCTURE
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1960-07-29 | 1961-01-28 | 1961-07-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1964-07-29 | 1965-01-28 | 1965-07-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1968-07-29 | 1969-01-28 | 1969-07-30 | $7700.00 | Window Closed / Lapsed |