Patent US4244729A successfully refreshed from Google Patents.
US4244729A
Expired / Lapsed
US
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Sustained release pesticide compositions and process for making same
Assignee: Westvaco Corp
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Filing: 1976-06-08
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Granted: 1981-01-13
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Expires: 1996-06-08
Abstract
Abstract A sustained release composition is disclosed which provides an improved carrier for an organic pesticide. The improved carrier is a reversibly swellable lignin gel made by cross-linking an alkali lignin with epichlorohydrin using particular conditions.
Inventors
- 👤 Humbert T. Dellicolli
- 👤 Peter Dilling
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 04:03
CPC Classifications
C; C08; C08H; C08H6/00; A; A01; A01N; A01N25/00; A01N25/08; A01N25/10
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
60 words
In a process for making a controlled release pesticide carrier, the improvement comprising, (a) reacting alkali lignin solution at a concentration of between 10% and 25% by volume with from 1 to 5 moles of epichlorohydrin at a temperature between about 50° C. and 100° C. for from 5 minutes to 2 hours to thereby form a reversibly swellable gel.
Claim 2
Dependent Claim
60 words
In a process for making a controlled release pesticide carrier, the improvement comprising, (a) reacting alkali lignin solution at a concentration of between 10% and 25% by volume with from 1 to 5 moles of epichlorohydrin at a temperature between about 50° C. and 100° C. for from 5 minutes to 2 hours to thereby form a reversibly swellable gel.
Claim 3
Dependent Claim
37 words
The process of claim 1 wherein up to 50% of a barrier material from the group consisting of sodium bicarbonate and sulfomethylated black liquor is added during the reaction, and washed out after the gel is formed.
References Cited (Backward Citations)
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US3718639A
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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) | 1984-01-13 | 1984-07-14 | 1985-01-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-01-13 | 1988-07-14 | 1989-01-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-01-13 | 1992-07-14 | 1993-01-13 | $7700.00 | Window Closed / Lapsed |