US4513034A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Variable permeability liquid crystalline membranes
Assignee: Merck and Co Inc
•
Filing: 1984-06-14
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Granted: 1985-04-23
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Expires: 2004-06-14
Abstract
Abstract The instant invention is directed to a variable permeability liquid crystalline membrane, comprising a porous structure containing a polymeric liquid crystal which can undergo a phase change. The instant invention is also directed to a process for regulating the flow of solutes or permeants through a liquid crystalline membrane, comprising changing the phase of a polymeric liquid crystal supported by a porous structure.
Inventors
- 👤 Randall V. Sparer
- 👤 Ravi K. Bhaskar
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 22:42
CPC Classifications
B; B01; B01D; B01D69/00; B01D69/14; B01D69/141; A; A61; A61K; A61K9/00; A61K9/10; A61K9/127; A61K9/1274; A61K9/20; A61K9/28; A61K9/2806; A61K9/2833; A61K9/2853; B01D61/00; B01D61/38; C; C09; C09K; C09K19/00; C09K19/04; C09K19/38; C09K19/3833; C09K19/389; G; G05; G05D; G05D7/00; G05D7/06; G05D7/0617; G05D7/0629; B01D71/00; B01D71/06; B01D71/08; B01D71/12; B01D71/14; C09K2323/00; C09K2323/06
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
21 words
A variable permeability liquid crystalline membrane, comprising a porous structure containing a polymeric liquid crystal which can undergo a phase change.
Claim 2
Dependent Claim
21 words
A variable permeability liquid crystalline membrane, comprising a porous structure containing a polymeric liquid crystal which can undergo a phase change.
Claim 3
Dependent Claim
15 words
The membrane of claim 1, wherein said porous substrate is a cellulose ester microporous membrane.
Claim 4
Dependent Claim
11 words
The membrane of claim 2, wherein said liquid crystal is poly-γ-benzyl-L-glutamate.
Claim 5
Dependent Claim
23 words
The membrane of claim 3, wherein 15 to 23%, by weight, of poly-γ-benzyl-L-glutamate and 77 to 85%, by weight, of solvent is used.
Claim 6
Dependent Claim
29 words
A process for regulating the diffusion of solutes or permeants through a liquid crystalline membrane, comprising changing the phase of a polymeric liquid crystal supported by a porous structure.
Claim 7
Dependent Claim
29 words
A process for regulating the diffusion of solutes or permeants through a liquid crystalline membrane, comprising changing the phase of a polymeric liquid crystal supported by a porous structure.
Claim 8
Dependent Claim
30 words
The process of claim 5, wherein the phase of said polymeric liquid crystal is changed by subjecting said crystal to an electric field of 300 to 500 volts per centimeter.
Claim 9
Dependent Claim
15 words
The process of claim 5, wherein said porous substrate is a cellulose ester microporous filter.
Claim 10
Dependent Claim
11 words
The process of claim 7, wherein said cellulose ester is poly-γ-benzyl-L-glutamate.
Claim 11
Dependent Claim
23 words
The process of claim 8, wherein 15 to 23%, by weight, of poly-γ-benzyl-L-glutamate and 77 to 85%, by weight, of solvent is used.
References Cited (Backward Citations)
US3871904A
Cited
US3977767A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1988-04-22 | 1988-10-22 | 1989-04-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-04-22 | 1992-10-22 | 1993-04-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-04-22 | 1996-10-22 | 1997-04-23 | $7700.00 | Window Closed / Lapsed |