Patent US4011393A successfully refreshed from Google Patents.
US4011393A
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Polygalactomannan gum formate esters
Assignee: Stein Hall and Co Inc
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Filing: 1975-04-28
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Granted: 1977-03-08
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Expires: 1995-04-28
Abstract
Abstract This invention provides novel guar gum formate esters having a degree of substitution between about 0.01 and 3.0, and further provides a process for producing guar gum formate esters by the interaction of guar gum powder or guar gum splits with concentrated formic acid. The invention process represents a general method for formylation of polygalactomannan gums. The polygalactomannan gum formate esters are useful as flocculants, and as sizing agents for paper and textiles.
Inventors
- 👤 Louis E. Trapasso
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 12:55
CPC Classifications
C; C08; C08B; C08B37/00; C08B37/006; C08B37/0087; C08B37/0093; C08B37/0096
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
73 words
A process for producing polygalactomannan gum formate esters which consists essentially of contacting solid polygalactomannan gum with concentrated formic acid solution, and a fluid organic medium which is a solvent for formic acid and essentially a non-solvent for solid polygalactomannan gum at a temperature between 0° and 60° C., and wherein the contact time is for a period sufficient to provide a predetermined degree of substitution by formate groups in the polygalactomannan gum.
Claim 2
Dependent Claim
73 words
A process for producing polygalactomannan gum formate esters which consists essentially of contacting solid polygalactomannan gum with concentrated formic acid solution, and a fluid organic medium which is a solvent for formic acid and essentially a non-solvent for solid polygalactomannan gum at a temperature between 0° and 60° C., and wherein the contact time is for a period sufficient to provide a predetermined degree of substitution by formate groups in the polygalactomannan gum.
Claim 3
Dependent Claim
18 words
A process in accordance with claim 1 wherein the polygalactomannan gum is guar gum or locust bean gum.
Claim 4
Dependent Claim
17 words
A process in accordance with claim 1 wherein the fluid organic medium is an aromatic hydrocarbon solvent.
Claim 5
Dependent Claim
16 words
A process in accordance with claim 3 wherein the aromatic hydrocarbon solvent is benzene or toluene.
References Cited (Backward Citations)
US3580841A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-03-07 | 1980-09-06 | 1981-03-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-03-07 | 1984-09-06 | 1985-03-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-03-07 | 1988-09-06 | 1989-03-08 | $7700.00 | Window Closed / Lapsed |