US3870701A
Expired / Lapsed
US
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Benzyl hydroxypropyl cellulose acetate and process
Assignee: Anheuser Busch Companies LLC
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Filing: 1973-10-15
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Granted: 1975-03-11
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Expires: 1993-10-15
Abstract
Abstract This disclosure involves the acetate ester of benzyl hydroxypropyl cellulose. This particular cellulose ester is useful as a gelling agent for organic solvents. The benzyl hydroxypropyl cellulose acetate is prepared by the simultaneous hydroxypropylation and benzylation of cellulose and by the continuation of the cellulose derivatization into acetylation. The overlapping relationship of the hydroxypropylation and acetylation processes is found to be effecient and economical in that it eliminates the difficulty of isolation and recovery of the water insoluble benzyl hydroxypropyl cellulose.
Inventors
- 👤 James Teng
- 👤 Marcella C Stubits
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 13:55
CPC Classifications
C; C08; C08B; C08B13/00
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
56 words
THE COMPOUND BENZYL HYDROXYPROPYL CELLULOSE ACETATE HAVING A DEGREE OF MOLAR SUBSTITUTION OF ABOUT 2 TO ABOUT 6 HYDROXYPROPYL GROUPS, A DEGREE OF SUBSTUTION OF BENZYL GROUPS OF ABOUT 0.1 TO ABOUT 0.8 AND A DEGREE OF SUBSTITUTION OF ACETYL GROUPS OF ABOUT 1.0 TO ABOUT 2.5 AND FURTHER CHARACTERIZED BY BEING SOLUBLE IN ORGINIC SOLVENTS.
Claim 2
Dependent Claim
56 words
THE COMPOUND BENZYL HYDROXYPROPYL CELLULOSE ACETATE HAVING A DEGREE OF MOLAR SUBSTITUTION OF ABOUT 2 TO ABOUT 6 HYDROXYPROPYL GROUPS, A DEGREE OF SUBSTUTION OF BENZYL GROUPS OF ABOUT 0.1 TO ABOUT 0.8 AND A DEGREE OF SUBSTITUTION OF ACETYL GROUPS OF ABOUT 1.0 TO ABOUT 2.5 AND FURTHER CHARACTERIZED BY BEING SOLUBLE IN ORGINIC SOLVENTS.
Claim 3
Dependent Claim
56 words
The compound benzyl hydroxypropyl cellulose acetate having a degree of molar substitution of about 2 to about 6 hydroxypropyl groups, a degree of substitution of benzyl groups of about 0.1 to about 0.8 and a degree of substitution of acetyl groups of about 1.0 to about 2.5 and further characterized by being soluble in organic solvents.
Claim 4
Dependent Claim
56 words
The compound benzyl hydroxypropyl cellulose acetate having a degree of molar substitution of about 2 to about 6 hydroxypropyl groups, a degree of substitution of benzyl groups of about 0.1 to about 0.8 and a degree of substitution of acetyl groups of about 1.0 to about 2.5 and further characterized by being soluble in organic solvents.
Claim 5
Dependent Claim
67 words
The process of preparing benzyl hydroxypropyl cellulose acetate which comprises the steps of hydroxypropylation, benzylation and acetylation of cellulose, and recovering a benzyl hydroxypropyl cellulose acetate having a degree of molar substitution of hydroxyl groups of about 2 to 6, a degree of substitution of benzyl groups of about 0.1 to about 0.8 and a degree of substitution of acetyl groups of about 1.0 to about 2.5.
Claim 6
Dependent Claim
67 words
The process of preparing benzyl hydroxypropyl cellulose acetate which comprises the steps of hydroxypropylation, benzylation and acetylation of cellulose, and recovering a benzyl hydroxypropyl cellulose acetate having a degree of molar substitution of hydroxyl groups of about 2 to 6, a degree of substitution of benzyl groups of about 0.1 to about 0.8 and a degree of substitution of acetyl groups of about 1.0 to about 2.5.
Claim 7
Dependent Claim
12 words
The process of claim 2 wherein propylene oxide is the hydroxyalkylation reagent.
Claim 8
Dependent Claim
12 words
The process of claim 2 wherein benzyl chloride is the benzylation reagent.
Claim 9
Dependent Claim
12 words
The process of claim 2 wherein acetic anhydride is the acetylation reagent.
Claim 10
Dependent Claim
31 words
The process of claim 2 wherein the steps of hydroxypropylation and benzylation occur simultaneously and the acetylation commences prior to the ending of the simultaneous hydroxypropylation and benzylation of the cellulose.
Claim 11
Dependent Claim
76 words
A gelled or thickened organic solvent composition comprising a major amount of an organic solvent having a solubility parameter of about 8 to about 12 and an effective amount of benzyl hydroxypropyl cellulose acetate having a degree of molar substitution of hydroxypropyl groups of about 2 to about 6, a degree of substitution of benzyl groups of about 0.1 to about 0.8, and a degree of substitution of acetyl groups of about 1.0 to about 2.5.
Claim 12
Dependent Claim
76 words
A gelled or thickened organic solvent composition comprising a major amount of an organic solvent having a solubility parameter of about 8 to about 12 and an effective amount of benzyl hydroxypropyl cellulose acetate having a degree of molar substitution of hydroxypropyl groups of about 2 to about 6, a degree of substitution of benzyl groups of about 0.1 to about 0.8, and a degree of substitution of acetyl groups of about 1.0 to about 2.5.
Claim 13
Dependent Claim
12 words
The process of claim 7 wherein the solvent is an organic solvent.
Claim 14
Dependent Claim
12 words
The process of claim 7 wherein the benzylation reagent is benzyl chloride.
Claim 15
Dependent Claim
12 words
The process of claim 7 wherein the hydroxypropylation reagent is propylene oxide.
Claim 16
Dependent Claim
82 words
A process of gelling an organic solvent fluid having a solubility parameter between about 8 and about 12, comprising adding to said fluid benzyl hydroxypropyl cellulose acetate in an amount to thicken or gel said fluid, said benzyl hydroxypropyl cellulose acetate having a degree of molar substitution of hydroxyl groups of about 2 to 6, a degree of substitution of benzyl groups of about 0.1 to about 0.8 and a degree of substitution of acetyl groups of about 1.0 to about 2.5.
Claim 17
Dependent Claim
82 words
A process of gelling an organic solvent fluid having a solubility parameter between about 8 and about 12, comprising adding to said fluid benzyl hydroxypropyl cellulose acetate in an amount to thicken or gel said fluid, said benzyl hydroxypropyl cellulose acetate having a degree of molar substitution of hydroxyl groups of about 2 to 6, a degree of substitution of benzyl groups of about 0.1 to about 0.8 and a degree of substitution of acetyl groups of about 1.0 to about 2.5.
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) | 1978-03-10 | 1978-09-09 | 1979-03-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-03-10 | 1982-09-09 | 1983-03-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-03-10 | 1986-09-09 | 1987-03-11 | $7700.00 | Window Closed / Lapsed |