Patent US2582009A successfully refreshed from Google Patents.
US2582009A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Preparation of cellulose acetate sulfates
Assignee: Eastman Kodak Co
•
Filing: 1949-07-13
•
Granted: 1952-01-08
•
Expires: 1969-07-13
Abstract
No abstract record available.
Inventors
- 👤 Carlton L Crane
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 11:53
CPC Classifications
C; C08; C08B; C08B7/00
Claims Analysis
Total Claims: 1
Claim 1
Independent Claim
42 words
A METHOD OF PREPARING CELLULOSE ACETATE SULFATES WHICH COMPRISES ESTERIFYING CELLULOSE IN AN ESTERIFICATION BATH MADE UP ESSENTIALLY OF 51-550 PARTS OF H2SO4 AND ACETIC ANHYDRIDE THE PARTS OF 100% ACETIC ANHYDRIDE PER 100 PARTS OF BONE DRY CELLULOSE BEING AT LEAST
References Cited (Backward Citations)
US1866532A
Cited
US2033787A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1955-01-07 | 1955-07-09 | 1956-01-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1959-01-07 | 1959-07-09 | 1960-01-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1963-01-07 | 1963-07-09 | 1964-01-08 | $7700.00 | Window Closed / Lapsed |