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US4244729A Expired / Lapsed US ⏱️ 0.0 years remaining

Sustained release pesticide compositions and process for making same

Assignee: Westvaco Corp
•
Filing: 1976-06-08
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Granted: 1981-01-13
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Expires: 1996-06-08
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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 03:45
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)

US3470148A Cited
US3699091A Cited
US3718639A Cited
US3726850A Cited
US3865803A Cited
US3905926A Cited
US3886101A Cited

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

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