US4979673A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Methods and devices for controlled release
Assignee: Individual
•
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 11:22
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.
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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) | 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 |