Patent US3971556A successfully refreshed from Google Patents.
US2536634A
Expired / Lapsed
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Process for the preparation of cellulosic esters
Assignee: Rhodiaceta SA
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Filing: 1947-09-23
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Granted: 1951-01-02
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Expires: 1967-09-23
Abstract
No abstract record available.
Inventors
- 👤 Fraizy Jean
- 👤 Rony Louis
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 12:52
CPC Classifications
C; C08; C08B; C08B3/00
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
64 words
A PROCESS FOR ACETYLATING CELLULOSE BY MEANS OF A BATH CONTAINING AN ACETYLATING AGENT, AN ACID CATALYST AND A SOLVENT FOR THE ACETATE TO BE FORMED, SAID PROCESS COMPRISING THE STEP OF NEUTRALIZING THE CATALYST BY ADDITION TO THE REACTION MIXTURE, DURING THE ACETYLATION REACTION PROPER, OF AN ORGANIC SUBSTANCE WITH A BASIC FUNCTION, SELECTED FROM THE GROUP CONSISTING OF ANILINE, PYRIDINE AND ACETAMIDE.
Claim 2
Dependent Claim
64 words
A PROCESS FOR ACETYLATING CELLULOSE BY MEANS OF A BATH CONTAINING AN ACETYLATING AGENT, AN ACID CATALYST AND A SOLVENT FOR THE ACETATE TO BE FORMED, SAID PROCESS COMPRISING THE STEP OF NEUTRALIZING THE CATALYST BY ADDITION TO THE REACTION MIXTURE, DURING THE ACETYLATION REACTION PROPER, OF AN ORGANIC SUBSTANCE WITH A BASIC FUNCTION, SELECTED FROM THE GROUP CONSISTING OF ANILINE, PYRIDINE AND ACETAMIDE.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1954-01-01 | 1954-07-03 | 1955-01-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1958-01-01 | 1958-07-03 | 1959-01-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1962-01-01 | 1962-07-03 | 1963-01-02 | $7700.00 | Window Closed / Lapsed |