US3874986A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Laminated porous/non-porous membranes
Assignee: General Electric Co
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Filing: 1974-05-20
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Granted: 1975-04-01
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Expires: 1994-05-20
Abstract
Abstract A unified laminate of layers of polymer is disclosed, the laminate consisting of a layer of microporous substrate and an ultrathin layer of polyphenylene oxide (PPO) with an ultrathin layer of organopolysiloxane-polycarbonate copolymer disposed therebetween. The organopolysiloxane-polycarbonate copolymer layer serves to join the outer two layers together and provide cushioning to compensate for minor surface imperfections in the substrate.
Inventors
- 👤 Warella R Browall
- 👤 Robert M Salemme
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 04:40
CPC Classifications
B; B32; B32B; B32B27/00; B32B27/06; B32B27/08; B01; B01D; B01D69/00; B01D69/12; B01D69/1213; B01D69/1216; B32B27/28; B32B27/283; B32B27/30; B32B27/304; B32B27/36; B32B27/365; Y; Y10; Y10T; Y10T428/00; Y10T428/249921; Y10T428/249953; Y10T428/249978; Y10T428/24998; Y10T428/249982; Y10T428/249985; Y10T428/31504; Y10T428/31507; Y10T428/31652; Y10T428/31663; Y10T428/31855; Y10T428/31909; Y10T428/31913; Y10T428/3192
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
49 words
A COMPOSITE CONTAINING UNIFIED LYERS OF POLYMER CONISTING OF A NON-POROUS LAYER OF POLYPHENYLENEOXIDE/ORGANOPOLYSILOXANE-POLYCARBONATE COPOLYMER, A BACKING LAYER OF A MATERIAL SELECTED FROM THE GROUP CONSISTING OF MICROPOROUS POLYVINYL CHLORIDE-ACRYLONITRILE COPOLYMER AND MICROPOROUS POLYCARBONATE AND AN INTERMEDIATE LAYER OF ORGANOPOLYSILOXANE-POLYCARBONATE COPOLYMER ADHERING SAID NON-POROUS LAYER TO SAID BACKING LAYER.
Claim 2
Dependent Claim
49 words
A COMPOSITE CONTAINING UNIFIED LYERS OF POLYMER CONISTING OF A NON-POROUS LAYER OF POLYPHENYLENEOXIDE/ORGANOPOLYSILOXANE-POLYCARBONATE COPOLYMER, A BACKING LAYER OF A MATERIAL SELECTED FROM THE GROUP CONSISTING OF MICROPOROUS POLYVINYL CHLORIDE-ACRYLONITRILE COPOLYMER AND MICROPOROUS POLYCARBONATE AND AN INTERMEDIATE LAYER OF ORGANOPOLYSILOXANE-POLYCARBONATE COPOLYMER ADHERING SAID NON-POROUS LAYER TO SAID BACKING LAYER.
Claim 3
Dependent Claim
12 words
The composite of claim 1 wherein the backing layer is microporous polycarbonate.
Claim 4
Dependent Claim
14 words
The composite of claim 1 wherein the backing layer is microporous polyvinyl chloride-acryLonitrile copolymer.
References Cited (Backward Citations)
US3740305A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-03-31 | 1978-09-30 | 1979-04-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-03-31 | 1982-09-30 | 1983-04-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-03-31 | 1986-09-30 | 1987-04-01 | $7700.00 | Window Closed / Lapsed |