US3626045A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for making tubular filaments
Assignee: COUSTAULDS Ltd
•
Filing: 1969-12-15
•
Granted: 1971-12-07
•
Expires: 1989-12-15
Abstract
Abstract A controllable commercial process for producing tubular regenerated cellulose filaments comprises extruding a viscose of a specific composition and containing sodium carbonate into a sulfuric acid spin bath of a specific composition to form filaments followed by stretching of the filaments. Tubular filaments with increased wet modulus and a tendency to crimp are produced by stretching the filaments by an amount approaching their breaking stretch.
Inventors
- 👤 Calvin R Woodings
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 10:53
CPC Classifications
D; D01; D01F; D01F2/00; D01F2/06; D01F2/08; D01F2/10; D01D; D01D5/00; D01D5/24; Y; Y10; Y10T; Y10T428/00; Y10T428/29; Y10T428/2913; Y10T428/2973; Y10T428/2975
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
21 words
A process as claimed in claim 1 in which the filaments are stretched in a hot, aqueous bath containing sulfuric acid.
Claim 2
Dependent Claim
24 words
A process as claimed in claim 1 in which the filaments are stretched by an amount approaching the stretch at which the filaments break.
Claim 3
Dependent Claim
29 words
A process as claimed in claim 3 in which the filaments are stretched by an amount which is about 10 percent below the stretch at which the filaments break.
References Cited (Backward Citations)
US1464048A
Cited
US2136463A
Cited
US2476293A
Cited
US2835551A
Cited
US3156605A
Cited
US3318990A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-12-06 | 1975-06-07 | 1975-12-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-12-06 | 1979-06-07 | 1979-12-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-12-06 | 1983-06-07 | 1983-12-07 | $7700.00 | Window Closed / Lapsed |