US4678684A
Expired / Lapsed
US
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Method for impregnating a thermoplastic polymer
Assignee: Hercules LLC
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Filing: 1986-03-21
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Granted: 1987-07-07
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Expires: 2006-03-21
Abstract
Abstract Disclosed is a method for impregnating a thermoplastic polymer with an impregnation material such as a fragrance or pest control agent or pharmaceutical composition. A thermoplastic polymer is impregnated by (1) dissolving an impregnation material such as a fragrance or pest control agent or pharmaceutical composition material in a volatile swelling agent maintained at or near supercritical conditions for the volatile swelling agent, (2) swelling the thermoplastic polymer by contacting it at or near supercritical conditions for the volatile swelling agent with the impregnation material-laden volatile swelling agent and then (3) reducing the pressure so that the volatile swelling agent diffuses out of the thus impregnated thermoplastic polymer.
Inventors
- 👤 Michael L. Sand
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 02:51
CPC Classifications
A; A61; A61K; A61K9/00; A61K9/70; A61K9/7007; A61L; A61L9/00; A61L9/015; A61L9/04; A61L9/042; B; B29; B29C; B29C71/00; C; C08; C08J; C08J7/00; C08J7/04; C08J7/06; C08J7/065; D; D06; D06M; D06M23/00; D06M23/10; D06M23/105; B29C71/0009; B29C2071/0018; B29C2071/0054; B29K; B29K2105/00; B29K2105/0005; B29K2105/0011; B29K2105/0029; Y; Y02; Y02P; Y02P20/00; Y02P20/50; Y02P20/54; Y10; Y10T; Y10T428/00; Y10T428/249921; Y10T428/249953; Y10T428/249954; Y10T428/249994; Y10T428/249995; Y10T428/249997
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
103 words
A method of forming an impregnated thermoplastic polymer, comprising: dissolving an impregnation material in a volatile swelling agent maintained at or near supercritical conditions for the volatile swelling agent, said impregnation material being selected from the group consisting of fragrances, pest control agents and pharmaceuticals; said swelling agent being selected from the group consisting of carbon dioxide, nitrous oxide; swelling the thermoplastic polymer by contacting it with the impregnation material-laden volatile swelling agent at or near supercritical conditions of temperture and pressure for the volatile swelling agent; and reducing the pressure whereby the volatile swelling agent diffuses out of the impregnated thermoplastic polymer.
Claim 2
Independent Claim
103 words
A method of forming an impregnated thermoplastic polymer, comprising: dissolving an impregnation material in a volatile swelling agent maintained at or near supercritical conditions for the volatile swelling agent, said impregnation material being selected from the group consisting of fragrances, pest control agents and pharmaceuticals; said swelling agent being selected from the group consisting of carbon dioxide, nitrous oxide; swelling the thermoplastic polymer by contacting it with the impregnation material-laden volatile swelling agent at or near supercritical conditions of temperture and pressure for the volatile swelling agent; and reducing the pressure whereby the volatile swelling agent diffuses out of the impregnated thermoplastic polymer.
Claim 3
Independent Claim
96 words
A method for impregnating a solid with an impregnation material comprising contacting the solid with a volatile solvent in which the impregnation material is dissolved and then reducing the pressure said solid being a thermoplastic polymer and the solvent also being a swelling agent for the polymer, the impregnation material being a fragrance, pest control agent or pharmaceutical agent and being less volatile than the volatile solvent, the polymer being contacted with and swollen by the solvent containing the impregnation material in solution at or near the supercritical conditions of temperature and pressure of the solvent.
Claim 4
Independent Claim
96 words
A method for impregnating a solid with an impregnation material comprising contacting the solid with a volatile solvent in which the impregnation material is dissolved and then reducing the pressure said solid being a thermoplastic polymer and the solvent also being a swelling agent for the polymer, the impregnation material being a fragrance, pest control agent or pharmaceutical agent and being less volatile than the volatile solvent, the polymer being contacted with and swollen by the solvent containing the impregnation material in solution at or near the supercritical conditions of temperature and pressure of the solvent.
Claim 5
Dependent Claim
12 words
The method of claim 2 wherein said impregnation material is a pharmaceutical.
Claim 6
Dependent Claim
14 words
The impregnation method as claimed in claim 2, wherein swelling agent is nitrous oxide.
Claim 7
Dependent Claim
15 words
The impregnation method as claimed in claim 2 wherein the swelling agent is carbon dioxide.
Claim 8
Dependent Claim
23 words
The impregnation method as claimed in claim 2 wherein the impregnation material is musk, rose oil, honeysuckle oil, pineoil, jasmine or oak musk.
Claim 9
Dependent Claim
17 words
The impregnation method as claimed in claim 2 wherein the impregnation material is pheromone or a pyrethrin.
Claim 10
Dependent Claim
23 words
The impregnation method as claimed in claim 2 wherein the impregnation material is a perfume, fruit fragrance, flower fragrance or pest control agent.
Claim 11
Dependent Claim
12 words
The impregnation method of claim 2 wherein said swelling agent is lipophilic.
Claim 12
Dependent Claim
12 words
The impregnation method of claim 2 wherein said impregnation material is fat-soluble.
Claim 13
Dependent Claim
10 words
The method of claim 3 wherein said pharmaceutical is scopolamine.
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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) | 1990-07-06 | 1991-01-05 | 1991-07-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-07-06 | 1995-01-05 | 1995-07-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-07-06 | 1999-01-05 | 1999-07-07 | $7700.00 | Window Closed / Lapsed |