US2768870A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Production of artificial filaments and other materials
Assignee: Textile & Chemical Res Co
•
Filing: 1953-05-11
•
Granted: 1956-10-30
•
Expires: 1973-05-11
Abstract
No abstract record available.
Inventors
- 👤 Drisch Nicolas
- 👤 Herrbach Paul
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 07:52
CPC Classifications
D; D01; D01F; D01F2/00; D01F2/24; D01F2/28
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
73 words
A PROCESS FOR THE PRODUCTION OF ARTIFICIAL FILAMENTS AND FILMS, WHICH COMPRISES ACETYLATION OF CELLULOSE WITH A MIXTURE OF ACETIC ACID AND ACETIC ANHYDRIDE IN THE PRESENCE OF SULPHURIC ACID AS A CATALYST, AND HYDRATION OF THE RESIDUAL ACETIC ANHYDRIDE, AND EXTRUDING THE THUS OBTAINED PRIMARY SOLUTION OF CELLULOSE TRIACETATE IN ACETIC ACID, IN THE PRESENCE OF RESIDUAL SULPHURIC ACID, INTO A BATH OF DILUTE ACETIC ACID AT A TEMPERATURE BELOW 25* C.
Claim 2
Dependent Claim
73 words
A PROCESS FOR THE PRODUCTION OF ARTIFICIAL FILAMENTS AND FILMS, WHICH COMPRISES ACETYLATION OF CELLULOSE WITH A MIXTURE OF ACETIC ACID AND ACETIC ANHYDRIDE IN THE PRESENCE OF SULPHURIC ACID AS A CATALYST, AND HYDRATION OF THE RESIDUAL ACETIC ANHYDRIDE, AND EXTRUDING THE THUS OBTAINED PRIMARY SOLUTION OF CELLULOSE TRIACETATE IN ACETIC ACID, IN THE PRESENCE OF RESIDUAL SULPHURIC ACID, INTO A BATH OF DILUTE ACETIC ACID AT A TEMPERATURE BELOW 25* C.
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) | 1959-10-30 | 1960-04-30 | 1960-10-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1963-10-30 | 1964-04-30 | 1964-10-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1967-10-30 | 1968-04-30 | 1968-10-30 | $7700.00 | Window Closed / Lapsed |