US4374891A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Ultrathin polymer membranes
Assignee: General Electric Co
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Filing: 1981-03-02
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Granted: 1983-02-22
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Expires: 2001-03-02
Abstract
Abstract An ultrathin polyphenylene oxide/organopolysiloxane-polycarbonate copolymer film is described wherein the film contains from about 10 to about 35 percent by weight of the organopolysiloxane-polycarbonate copolymer.
Inventors
- 👤 William J. Ward, III
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 16:33
CPC Classifications
B; B01; B01D; B01D71/00; B01D71/06; B01D71/76; B01D71/80; B01D69/00; B01D69/12; B01D69/122; B29; B29D; B29D7/00; B29D7/01; Y; Y10; Y10T; Y10T428/00; Y10T428/31504; Y10T428/31652; Y10T428/31663
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
52 words
A film consisting of a blend of polyphenylene oxide and organopolysiloxane-polycarbonate copolymer exhibiting an oxygen/nitrogen separating factor having a value of at least 4.0, said film containing from about 10 to about 35% by weight of the total blend of organopolysiloxane-polycarbonate copolymer and having a thickness of less than about 200 A.
Claim 2
Dependent Claim
52 words
A film consisting of a blend of polyphenylene oxide and organopolysiloxane-polycarbonate copolymer exhibiting an oxygen/nitrogen separating factor having a value of at least 4.0, said film containing from about 10 to about 35% by weight of the total blend of organopolysiloxane-polycarbonate copolymer and having a thickness of less than about 200 A.
Claim 3
Dependent Claim
22 words
The film as recite in claim 1 wherein the percent by weight of organopolysiloxane-polycarbonate copolymer is about 20% of the total blend.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1986-02-21 | 1986-08-23 | 1987-02-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-02-21 | 1990-08-23 | 1991-02-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-02-21 | 1994-08-23 | 1995-02-22 | $7700.00 | Window Closed / Lapsed |