Patent US3007764A successfully refreshed from Google Patents.
US3007764A
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Process of preparing viscose rayon
Assignee: EIDP Inc
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Filing: 1957-10-01
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Granted: 1961-11-07
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Expires: 1977-10-01
Abstract
No abstract record available.
Inventors
- 👤 Gage Thomas Barton
- 👤 Walker Joseph Frederic
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 05:38
CPC Classifications
D; D01; D01F; D01F2/00; D01F2/06; D01F2/08; D01F2/10
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
102 words
IN THE PROCESS OF PRODUCING A SHAPED STRUCTURE OF REGENERATED CELLULOSE BY EXTRUDING VISCOSE INTO A FORMALDEHYDE-CONTAINING, 4 TO 12% SULFURIC ACID BATH CONTAINING 5 TO 25% SODIUM SULFATE, THE IMPROVEMENT WHICH COMPRISES EXTRUDING THE VISCOSE IN THE PRESENCE OF A NITROGEN DERIVATIVE TO PREVENT THE FORMATION OF HARD CRYSTALLINE DEPOSITS CONSISTING PRIMARILY OF TRITHIANE, SAID NITROGEN DERIVATIVE BEING SELECTED FROM THE GROUP CONSISTING OF AMMONIUM SULFATE, FORMAMIDE, N-METHYL FORMAMIDE, ACETAMIDE, N-METHYL ACETAMIDE, N,N-DIMETHYL ACETAMIDE, N,N''-DIMETHYL UREA AND 3,3-DIMETHYL HYDANTOIN, THE MAXIMUM AMOUNT OF FORMALDEHYDE IN THE BATH BEING A MOLAR AMOUNT APPROXIMATELY EQUAL TO THE MOLAR AMOUNT OF SAID NITROGEN DERIVATIVE.
Claim 2
Dependent Claim
102 words
IN THE PROCESS OF PRODUCING A SHAPED STRUCTURE OF REGENERATED CELLULOSE BY EXTRUDING VISCOSE INTO A FORMALDEHYDE-CONTAINING, 4 TO 12% SULFURIC ACID BATH CONTAINING 5 TO 25% SODIUM SULFATE, THE IMPROVEMENT WHICH COMPRISES EXTRUDING THE VISCOSE IN THE PRESENCE OF A NITROGEN DERIVATIVE TO PREVENT THE FORMATION OF HARD CRYSTALLINE DEPOSITS CONSISTING PRIMARILY OF TRITHIANE, SAID NITROGEN DERIVATIVE BEING SELECTED FROM THE GROUP CONSISTING OF AMMONIUM SULFATE, FORMAMIDE, N-METHYL FORMAMIDE, ACETAMIDE, N-METHYL ACETAMIDE, N,N-DIMETHYL ACETAMIDE, N,N''-DIMETHYL UREA AND 3,3-DIMETHYL HYDANTOIN, THE MAXIMUM AMOUNT OF FORMALDEHYDE IN THE BATH BEING A MOLAR AMOUNT APPROXIMATELY EQUAL TO THE MOLAR AMOUNT OF SAID NITROGEN DERIVATIVE.
References Cited (Backward Citations)
US2227367A
Cited
US2225604A
Cited
US2452130A
Cited
US2535045A
Cited
US2535044A
Cited
US2893821A
Cited
US2860480A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1964-11-06 | 1965-05-08 | 1965-11-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1968-11-06 | 1969-05-08 | 1969-11-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1972-11-06 | 1973-05-08 | 1973-11-07 | $7700.00 | Window Closed / Lapsed |