US3720663A
Expired / Lapsed
US
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Preparation of starch esters
Assignee: Indopco Inc
•
Filing: 1971-06-24
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Granted: 1973-03-13
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Expires: 1991-06-24
Abstract
Abstract Aqueous slurries or dispersions of starch are reacted with imadazolides of carboxylic or sulfonic acids to yield starch ester derivatives. These starch products can also be prepared in non-aqueous solvents or by a dry reaction process.
Inventors
- 👤 M Tessler
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 15:56
CPC Classifications
C; C08; C08B; C08B31/00; C08B31/02; C08B31/06
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
32 words
A process for preparing esters of a starch having free reactive hydroxyl groups comprising the steps of: a. reacting said starch with an imidazolide-acid reaction product selected from the group consisting of
Claim 2
Dependent Claim
32 words
A process for preparing esters of a starch having free reactive hydroxyl groups comprising the steps of: a. reacting said starch with an imidazolide-acid reaction product selected from the group consisting of
Claim 3
Dependent Claim
47 words
A process according to claim 1 wherein said starch is reacted with said imidazolide in an aqueous medium at a pH of from about 4.0 to about 12.5 and at a temperature of about 35* to 125* F. for a period of from 1 to 24 hours.
Claim 4
Dependent Claim
35 words
A process according to claim 1 wherein the reaction is carried out in a non-aqueous liquid medium at a temperature of about 35* to 125* F. for a period of from 1 to 24 hours.
Claim 5
Dependent Claim
36 words
A process according to claim 1 wherein the reaction is carried out employing a substantially dry reaction medium at a temperature of about 80* to 160* F. for a period of from 0.5 to 6 hours.
Claim 6
Dependent Claim
12 words
A process according to claim 1 wherein said starch is corn starch.
Claim 7
Dependent Claim
12 words
A process according to claim 1 wherein said starch is waxy maize.
Claim 8
Dependent Claim
13 words
A process according to claim 1 wherein the starch is reacted with 1,1''-carbonyldiimidazole.
Claim 9
Dependent Claim
17 words
A process according to claim 1 wherein the starch is reacted with the diimidazolide of succinic acid.
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) | 1976-03-12 | 1976-09-11 | 1977-03-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-03-12 | 1980-09-11 | 1981-03-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-03-12 | 1984-09-11 | 1985-03-13 | $7700.00 | Window Closed / Lapsed |