Patent US4979673A successfully refreshed from Google Patents.
US4979673A
Expired / Lapsed
US
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Methods and devices for controlled release
Assignee: Individual
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Filing: 1986-12-18
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Granted: 1990-12-25
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Expires: 2006-12-18
Abstract
Abstract A device is disclosed which achieves a constant rate of release of an active ingredient in the temperature range of 5° to 45° C., which comprises a container having at least a portion of its surface membrane consisting essentially of polyethylene, polypropylene, or copolymers thereof, said membrane having a thickness of less than 6 mil, and within the container a solution of active ingredient in a solvent in contact with a negative release modulator, wherein the negative release modulator is less miscible with the solution at 5° C. than at 45° C.
Inventors
- 👤 Immanuel J. Wilk
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 11:38
CPC Classifications
A; A61; A61L; A61L9/00; A61L9/015; A61L9/04; A61L9/042; A01; A01N; A01N25/00; A01N25/18
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
97 words
A device which achieves a constant rate of release of an active ingredient over a temperature range of 5°-45° C., which comprises a container having as at least a portion of its surface a permeable membrane of thickness less than 6 mil; and within the container a solution of active ingredient in a solvent compatible with said permeable membrane in contact with a negative release modulator; wherein said permeable membrane is permeable to the active ingredient in said solution; and wherein said negative release modulator is less miscible with the solution at 5° than at 45° C.
Claim 2
Independent Claim
97 words
A device which achieves a constant rate of release of an active ingredient over a temperature range of 5°-45° C., which comprises a container having as at least a portion of its surface a permeable membrane of thickness less than 6 mil; and within the container a solution of active ingredient in a solvent compatible with said permeable membrane in contact with a negative release modulator; wherein said permeable membrane is permeable to the active ingredient in said solution; and wherein said negative release modulator is less miscible with the solution at 5° than at 45° C.
Claim 3
Dependent Claim
25 words
The device of claim 1 wherein the membrane consists essentially of polyethylene, polypropylene or copolymers thereof and the negative release modulator is a silicone oil.
Claim 4
Dependent Claim
23 words
A method for releasing an active ingredient into the environment, which comprises placing the device of claim 1 in contact with said environment.
References Cited (Backward Citations)
US3852419A
Cited
US4160335A
Cited
US3961628A
Cited
US3951622A
Cited
US4406883A
Cited
US4237113A
Cited
US4320873A
Cited
US4325941A
Cited
US4387849A
Cited
GB2137497A
Cited
JPS58189101A
Cited
US4608048A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1993-12-24 | 1994-06-25 | 1994-12-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-12-24 | 1998-06-25 | 1998-12-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-12-24 | 2002-06-25 | 2002-12-25 | $7700.00 | Window Closed / Lapsed |