US4528125A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Sustained release compositions
Assignee: Dow Chemical Co
•
Filing: 1983-03-03
•
Granted: 1985-07-09
•
Expires: 2003-03-03
Abstract
Abstract Dispersions capable of the sustained release of active organic agents comprising an aqueous dispersion of a water-insoluble cellulose ether which cellulose ether particles have reversibly diffused therein the active agent. The dispersions may be used as dispersions, dewatered to form a powder, or coalesced to form films or other articles all of which are capable of sustained release of the active agent.
Inventors
- 👤 Daniel A. Alderman
- 👤 Maurice L. Zweigle
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 14:42
CPC Classifications
C; C08; C08L; C08L1/00; C08L1/08; C08L1/26; A; A61; A61K; A61K8/00; A61K8/18; A61K8/72; A61K8/73; A61K8/731; A61K9/00; A61K9/14; A61K9/141; A61K9/146; A61Q; A61Q11/00; A61Q13/00
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
54 words
An aqueous dispersion capable of a sustained release of a fragrance, said dispersion comprising a plurality of particles of a water-insoluble, organophilic cellulose ether dispersed into an aqueous phase, said cellulose ether having reversibly diffused therein an organic fragrance which fragrance exhibits a greater affinity for the cellulose ether than for the aqueous phase.
Claim 2
Dependent Claim
54 words
An aqueous dispersion capable of a sustained release of a fragrance, said dispersion comprising a plurality of particles of a water-insoluble, organophilic cellulose ether dispersed into an aqueous phase, said cellulose ether having reversibly diffused therein an organic fragrance which fragrance exhibits a greater affinity for the cellulose ether than for the aqueous phase.
Claim 3
Dependent Claim
13 words
The dispersion of claim 1 wherein the cellulose ether is ethylcellulose or ethylhydroxypropylmethylcellulose.
Claim 4
Dependent Claim
19 words
The dispersion of claim 1 wherein the fragrance comprises an essential oil, a plant extract, or an aroma chemical.
Claim 5
Dependent Claim
21 words
The dispersion of claim 1 further comprising a compatibilizing material which increases the compatibility of the fragrance and the cellulose ether.
Claim 6
Dependent Claim
37 words
The dispersion of claim 4 wherein the compatibilizing material comprises a fatty acid or salt or ester thereof; phthallic acid or esters thereof; a fatty alcohol; a phosphate ester; or a glycol ester of a carboxylic acid.
Claim 7
Dependent Claim
19 words
The dispersion of claim 5 wherein the fragrance comprises an essential oil, a plant extract, or an aroma chemical.
Claim 8
Dependent Claim
18 words
The dispersion of claim 6 wherein the compatibilizing material is dibutylphthalate or a fatty acid or salt thereof.
Claim 9
Dependent Claim
13 words
The dispersion of claim 7 wherein the cellulose ether is ethylcellulose or ethylhydroxypropylmethylcellulose.
Claim 10
Dependent Claim
58 words
The dispersion of claim 1 wherein the aqueous dispersion comprises particles of ethylcellulose or ethylhydroxypropylmethylcellulose, which particles are plasticized with a plastizicing composition comprising a carboxylic acid which is a plasticizer for said cellulose ether, and the aqueous phase has a pH sufficiently high that sufficient of the carboxylic acid is in salt form to stabilize the dispersion.
Claim 11
Dependent Claim
13 words
The dispersion of claim 9 wherein the carboxylic acid is a fatty acid.
Claim 12
Dependent Claim
19 words
The dispersion of claim 10 wherein the fragrance comprises an essential oil, a plant extract, or an aroma chemical.
Claim 13
Dependent Claim
18 words
A powder containing an organic fragrance, which powder is formed by dewatering of the dispersion of claim 1.
Claim 14
Dependent Claim
18 words
A powder containing an organic fragrance, which powder is formed by dewatering of the dispersion of claim 9.
Claim 15
Dependent Claim
25 words
A film or other article containing the organic fragance, which film or other article is formed by the coalescence of the dispersion of claim 1.
Claim 16
Dependent Claim
25 words
A film or other article containing the organic fragrance, which film or other article is formed by the coalescence of the dispersion of claim 9.
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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) | 1988-07-08 | 1989-01-07 | 1989-07-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-07-08 | 1993-01-07 | 1993-07-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-07-08 | 1997-01-07 | 1997-07-09 | $7700.00 | Window Closed / Lapsed |