US2544902A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Preparation of soluble nitrocellulose having carboxyl groups in the primary position
Assignee: Eastman Kodak Co
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Filing: 1948-04-10
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Granted: 1951-03-13
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Expires: 1968-04-10
Abstract
No abstract record available.
Inventors
- 👤 William E Sillick
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 22:22
CPC Classifications
C; C08; C08B; C08B7/00
Claims Analysis
Total Claims: 1
Claim 1
Independent Claim
93 words
A METHOD OF PREPARING AN ACETONE-SOLUBLE CELLULOSE DERIVATIVE WHICH COMPRISES NITRATING CELLULOSE HAVING A CARBOXYL CONTENT OF .05% TO 6% ON THE PRIMARY GROUPS OF THE CELLULOSE WITH A NITRATING BATH ESSENTIALLY CONSISTING OF A MIXTURE OF HNO3 AND H2SO4, OF 80-98% STRENGTH, EACH ACID CONSTITUTING 40-60% OF THE TOTAL ACID PRESENT, SO AS TO IMPART A NITROGEN CONTENT OF 10.5-12.2% THERETO AN ACETONE-INSOLUBLE AND ALKALI-INSOLUBLE PRODUCT RESULTING AND SUBSEQUENTLY SOAKING THE PRODUCT SO OBTAINED IN DILUTE AQUEOUS SODIUM HYDROXIDE HAVING A CONCENTRATION OF .01-0.4% UNTIL A SUBSTANTIALLY COMPLETELY ACETONE-SOLUBLE PRODUCT IS OBTAINED.
References Cited (Backward Citations)
US2256391A
Cited
US2472591A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1954-03-12 | 1954-09-11 | 1955-03-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1958-03-12 | 1958-09-11 | 1959-03-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1962-03-12 | 1962-09-11 | 1963-03-13 | $7700.00 | Window Closed / Lapsed |