US3945926A
Expired / Lapsed
US
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Integral microporous high void volume polycarbonate membranes and a dry process for forming same
Assignee: GELSUB Inc
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Filing: 1972-10-02
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Granted: 1976-03-23
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Expires: 1992-10-02
Abstract
Abstract Integral, skinned and unskinned, microporous microfiltration and ultrafiltration, electrophoresis membranes having high void volumes (above 50% void) composed of polycarbonates and copolymers of polycarbonates with polyalkylene oxides and the dry process for producing such membranes are disclosed.
Inventors
- 👤 Robert E. Kesting
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 18:12
CPC Classifications
B; B01; B01D; B01D71/00; B01D71/06; B01D71/50; B01D69/00; B01D69/02; C; C08; C08G; C08G64/00; C08G64/18; C08G64/183; C08J; C08J9/00; C08J9/28; C08J2369/00
Claims Analysis
Total Claims: 25
Claim 1
Independent Claim
46 words
As an article of manufacture, integral, high void volume polycarbonate resin membrane prepared by the dry phase inversion process being composed of polycarbonate polymer or polycarbonate-polyalkylene oxide copolymer having a molecular weight greater than about 46,000 (η = 75), and having a void volume above 65%.
Claim 2
Dependent Claim
46 words
As an article of manufacture, integral, high void volume polycarbonate resin membrane prepared by the dry phase inversion process being composed of polycarbonate polymer or polycarbonate-polyalkylene oxide copolymer having a molecular weight greater than about 46,000 (η = 75), and having a void volume above 65%.
Claim 3
Dependent Claim
28 words
The membranes as defined in claim 1 wherein the molecular weight is in the range of from about 46,000 [η = 75) to about 145,000 (η = 190).
Claim 4
Dependent Claim
19 words
The membranes as defined in claim 2 wherein the void volume is above 65% and the membrane is unskinned.
Claim 5
Dependent Claim
18 words
The membranes as defined in claim 2 wherein the void volume is between about 70% and about 85%.
Claim 6
Dependent Claim
28 words
The membranes as defined in claim 2 wherein the molecular weight is in the range of from about 70,000 (η = 100) to about 145,000 (η = 190).
Claim 7
Dependent Claim
29 words
The membranes as defined in claim 5 wherein the molecular weight is in the optimum range of from about 110,000 (η = 150) to about 130,000 [η = 175).
Claim 8
Dependent Claim
20 words
The membranes as defined in claim 6 wherein the membranes are unskinned and have a matte finish on both sides.
Claim 9
Dependent Claim
18 words
The membranes as defined in claim 6 wherein the void volume is between about 70% and about 85%.
Claim 10
Dependent Claim
20 words
The membranes as defined in claim 8 wherein the membranes are unskinned and have a matte finish on both sides.
Claim 11
Dependent Claim
18 words
The membranes as defined in claim 5 wherein the void volume is between about 70% and about 85%.
Claim 12
Dependent Claim
20 words
The membranes as defined in claim 10 wherein the membranes are unskinned and have a matte finish on both sides.
Claim 13
Dependent Claim
137 words
Integral, microporous membranes having a void volume above 50% consisting essentially of polycarbonate resin having the structure ##EQU10## or the structure ##EQU11## wherein : n is an integer greater than about 180, x is an integer from about 180 to about 600, y is an integer from about 1 to about 6, z is an integer from about 13 to about 450, R is a radical selected from the group consisting of H--, (CH 3 ) 2 CH--, and ##SPC7## R' is a radical selected from the group consisting of ##SPC8## and ##EQU12## and substituted derivatives thereof, and wherein R" is a radical selected from the group consisting of ##EQU13## and ##EQU14## wherein a and b are integers ranging from about 3 to about 10 and c is an integer ranging from about 20 to about 50.
Claim 14
Dependent Claim
137 words
Integral, microporous membranes having a void volume above 50% consisting essentially of polycarbonate resin having the structure ##EQU10## or the structure ##EQU11## wherein : n is an integer greater than about 180, x is an integer from about 180 to about 600, y is an integer from about 1 to about 6, z is an integer from about 13 to about 450, R is a radical selected from the group consisting of H--, (CH 3 ) 2 CH--, and ##SPC7## R' is a radical selected from the group consisting of ##SPC8## and ##EQU12## and substituted derivatives thereof, and wherein R" is a radical selected from the group consisting of ##EQU13## and ##EQU14## wherein a and b are integers ranging from about 3 to about 10 and c is an integer ranging from about 20 to about 50.
Claim 15
Dependent Claim
15 words
The membranes as defined in claim 12 wherein the void volume is above about 65%.
Claim 16
Dependent Claim
20 words
The membranes as defined in claim 13 wherein the membranes are unskinned and have a matte finish on both sides.
Claim 17
Dependent Claim
18 words
The membranes as defined in claim 13 wherein the void volume is between about 70% and about 85%.
Claim 18
Dependent Claim
20 words
The membranes as defined in claim 15 wherein the membranes are unskinned and have a matte finish on both sides.
Claim 19
Dependent Claim
21 words
The membranes as defined in claim 12 wherein the molecular weight of the polycarbonate resin is above 46,000 (η = 75).
Claim 20
Dependent Claim
28 words
The membranes as defined in claim 17 wherein the molecular weight of the polycarbonate resin is between about 70,000 (η = 100) and about 145,000 (η = 190).
Claim 21
Dependent Claim
15 words
The membranes as defined in claim 18 wherein the void volume is above about 65%.
Claim 22
Dependent Claim
20 words
The membranes as defined in claim 19 wherein the membranes are unskinned and have a matte finish on both sides.
Claim 23
Dependent Claim
28 words
The membranes as defined in claim 19 wherein the molecular weight to the polycarbonate resin is between about 110,000 (η = 150) and about 130,000 (η = 175).
Claim 24
Dependent Claim
18 words
The membranes as defined in claim 21 wherein the void volume is between about 70% and about 85%.
Claim 25
Dependent Claim
20 words
The membranes as defined in claim 22 wherein the membranes are unskinned and have a matte finish on both sides.
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) | 1979-03-23 | 1979-09-22 | 1980-03-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-03-23 | 1983-09-22 | 1984-03-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-03-23 | 1987-09-22 | 1988-03-23 | $7700.00 | Window Closed / Lapsed |