US4391973A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Readily hydratable cellulose and preparation thereof
Assignee: Morca Inc
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Filing: 1981-08-17
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Granted: 1983-07-05
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Expires: 2001-08-17
Abstract
Abstract Readily hydratable cellulose products prepared by acid treatment of highly fibrillated filbrillatable cellulose precursor such as wood pulps. Highly flocculent slurries are formed when the products are mixed in water. The slurries exhibit slow settling rates and the material gradually settles, after prolonged standing, into a highly flocculent, uncompacted mass below a layer of crystal clear aqueous medium.
Inventors
- 👤 Mamerto M. Cruz, Jr.
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 23:15
CPC Classifications
C; C08; C08B; C08B1/00; C08B15/00; C08B15/02
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
46 words
The method of producing water-insoluble cellulose particles that form floc-like slurries when mixed in water which comprises subjecting a mechanically fibrillated fibrillatable cellulose precursor to hydrolysis by the use of an aqueous solution of a non-derivatizing mineral acid and recovering water-insoluble, highly hydrated, floc-like cellulose particles.
Claim 2
Independent Claim
46 words
The method of producing water-insoluble cellulose particles that form floc-like slurries when mixed in water which comprises subjecting a mechanically fibrillated fibrillatable cellulose precursor to hydrolysis by the use of an aqueous solution of a non-derivatizing mineral acid and recovering water-insoluble, highly hydrated, floc-like cellulose particles.
Claim 3
Dependent Claim
29 words
The method as defined in claim 1 wherein the mechanically fibrillated, fibrillatable cellulose precursor is a wood pulp having a Schopper-Riegler (ml/SR) of between about 100 and about 650.
Claim 4
Dependent Claim
26 words
The method as defined in claim 1 wherein the mechanically fibrillated, fibrillatable cellulose precursor is a wood pulp having a Schopper-Riegler (ml/SR) of 100 to 450.
Claim 5
Dependent Claim
24 words
The method as defined in claim 1 wherein the aqueous solution of mineral acid is an 8 to 10% aqueous solution of hydrochloric acid.
Claim 6
Dependent Claim
18 words
The method as defined in claim 1 wherein the recovered water-insoluble, highly hydrated, floc-like cellulose particles are dried.
Claim 7
Dependent Claim
23 words
The method as defined in claim 1 wherein the recovered water-insoluble, highly hydrated, floc-like cellulose particles are recovered as a slurry in water.
Claim 8
Dependent Claim
58 words
As an article of manufacture, water-insoluble, non-gritty cellulose particles characterized in forming water-insoluble, highly hydrated floc-like particles when slurried in an aqueous medium, the slurries settling into highly flocculent, uncompacted masses below a layer of crystal clear aqueous medium upon prolonged standing of the slurries and further characterized in having been prepared by the method of claim 1.
Claim 9
Dependent Claim
25 words
An article of manufacture as defined in claim 7 wherein the cellulose particles are in the form of floc-like particles slurried in an aqueous solution.
Claim 10
Dependent Claim
18 words
An article of manufacture as defined in claim 7 wherein the cellulose particles are in a dry state.
References Cited (Backward Citations)
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1986-07-04 | 1987-01-03 | 1987-07-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-07-04 | 1991-01-03 | 1991-07-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-07-04 | 1995-01-03 | 1995-07-05 | $7700.00 | Window Closed / Lapsed |