US4028132A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Cellulose solutions and products prepared therefrom
Assignee: Playtex Products LLC
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Filing: 1975-11-25
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Granted: 1977-06-07
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Expires: 1995-11-25
Abstract
Abstract Solutions of cellulose in hydrazine are formed by dissolving cellulose therein. The cellulose solutions formed may be utilized for the preparation of fibers, films, foams or other cellulose fabricated articles. Alternatively, the dissolution of cellulose in hydrazine may be employed as a means for the direct extraction of cellulose from lignocellulosic materials without the necessity of pulping operations.
Inventors
- 👤 Morton H. Litt
- 👤 Narayan Ganesh Kumar
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 21:40
CPC Classifications
C; C08; C08J; C08J9/00; C08J9/04; C08J9/12; C08J9/14; C08B; C08B1/00; C08B1/003; C08J2301/00; C08J2301/02
Claims Analysis
Total Claims: 21
Claim 1
Independent Claim
18 words
A solution of cellulose in hydrazine where in the solvent medium comprises at least 30% by weight hydrazine.
Claim 2
Dependent Claim
18 words
A solution of cellulose in hydrazine where in the solvent medium comprises at least 30% by weight hydrazine.
Claim 3
Dependent Claim
15 words
The solution of claim 1, in which the solvent medium comprises at least 50% hydrazine.
Claim 4
Dependent Claim
15 words
The solution of claim 1, in which the solvent medium comprises at least 70% hydrazine.
Claim 5
Dependent Claim
8 words
The solution of claim 1 containing a diluent.
Claim 6
Dependent Claim
10 words
The solution of claim 4, wherein the diluent is water.
Claim 7
Dependent Claim
33 words
A process for the preparation of a cellulose product, which comprises dissolving cellulose in a solvent medium having at least 30% by weight hydrazine, and preparing the cellulose product from the resulting solution.
Claim 8
Dependent Claim
33 words
A process for the preparation of a cellulose product, which comprises dissolving cellulose in a solvent medium having at least 30% by weight hydrazine, and preparing the cellulose product from the resulting solution.
Claim 9
Dependent Claim
22 words
The process of claim 6, wherein the solvent medium in which the cellulose is dissolved comprises at least 50% by weight hydrazine.
Claim 10
Dependent Claim
22 words
The process of claim 6 wherein the solvent medium in which the cellulose is dissolved comprises at least 70% by weight hydrazine.
Claim 11
Dependent Claim
18 words
The process of claim 6, wherein the cellulose is dissolved at temperatures of from 100° to 250° C.
Claim 12
Dependent Claim
20 words
The process of claim 6, in which the cellulose dissolved has a degree of polymerization of from 50 to 2,500.
Claim 13
Dependent Claim
14 words
The process of claim 6, wherein the hydrazine solvent is admixed with a diluent.
Claim 14
Dependent Claim
10 words
The process of claim 11, wherein the diluent is water.
Claim 15
Dependent Claim
15 words
The process of claim 6, in which the solution is spun into a cellulose fiber.
Claim 16
Dependent Claim
15 words
The process of claim 6, in which the solution is extruded into a cellulose film.
Claim 17
Dependent Claim
15 words
The process of claim 6, in which the solution is formed into a cellulose foam.
Claim 18
Dependent Claim
33 words
A process for the separation of cellulose from admixture with lignocellulosic materials, which comprises dispersing the mixture in a solvent medium having at least 30% by weight hydrazine and separating the cellulose therefrom.
Claim 19
Dependent Claim
33 words
A process for the separation of cellulose from admixture with lignocellulosic materials, which comprises dispersing the mixture in a solvent medium having at least 30% by weight hydrazine and separating the cellulose therefrom.
Claim 20
Dependent Claim
22 words
The process of claim 16, wherein the solvent medium in which the mixture is dispersed comprises at least 50% by weight hydrazine.
Claim 21
Dependent Claim
22 words
The process of claim 16, wherein the solvent medium in which the cellulose is dispersed comprises at least 70% by weight hydrazine.
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) | 1980-06-06 | 1980-12-06 | 1981-06-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-06-06 | 1984-12-06 | 1985-06-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-06-06 | 1988-12-06 | 1989-06-07 | $7700.00 | Window Closed / Lapsed |