US4529793A
Expired / Lapsed
US
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Selective permeable membranes comprising a polyquinazolone-based polymer
Assignee: Nitto Denko Corp
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Filing: 1983-06-20
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Granted: 1985-07-16
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Expires: 2003-06-20
Abstract
Abstract A selective permeable membrane comprising a polyquinazolone-based polymer including a repeating unit represented by the formula <IMAGE> wherein R1 is a tetravalent aromatic group, R2a and R2b are each independently, an alkyl group or aromatic group, and R3 is a divalent organic group.
Inventors
- 👤 Masao Abe
- 👤 Akio Iwama
- 👤 Yuzuru Noda
- 👤 Hisashi Ichinose
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 03:43
CPC Classifications
C; C08; C08G; C08G73/00; C08G73/06; C08G73/0683; C08G73/0694; B; B01; B01D; B01D71/00; B01D71/06; B01D71/58; B01D71/62
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
113 words
A selective permeable membrane comprising a polyquinazolone-based polymer having a repeating unit (Ia) represented by the formula ##STR26## wherein R 1 is a tetravalent aromatic group, R 2a and R 2b are each independently an alkyl group or aromatic group, and R 3 is a divalent organic group, and a repeating unit (Ib) represented by the formula ##STR27## wherein R 1 , R 2a and R 2b have the same meanings as defined above, R 4 is an aromatic group having a (p+2) valency, each Z is independently selected from the group consisting of COOH, --SO 3 H or a metal salt thereof, and p is an integer of from 1 to 4.
Claim 2
Dependent Claim
113 words
A selective permeable membrane comprising a polyquinazolone-based polymer having a repeating unit (Ia) represented by the formula ##STR26## wherein R 1 is a tetravalent aromatic group, R 2a and R 2b are each independently an alkyl group or aromatic group, and R 3 is a divalent organic group, and a repeating unit (Ib) represented by the formula ##STR27## wherein R 1 , R 2a and R 2b have the same meanings as defined above, R 4 is an aromatic group having a (p+2) valency, each Z is independently selected from the group consisting of COOH, --SO 3 H or a metal salt thereof, and p is an integer of from 1 to 4.
Claim 3
Dependent Claim
130 words
A selective permeable membrane as in claim 1 wherein R 1 is selected from the groups represented by the formulae ##STR28## wherein X is a divalent organic linking group, R 2a and R 2b are each independently alkyl groups containing from 1 to 4 carbon atoms or aromatic groups, R 3 is selected from the groups represented by the formulae ##STR29## wherein Y is a divalent organic linking group, and R 4 is selected from the groups represented by the formulae ##STR30## wherein X is a divalent organic linking group, Z is --COOH, --SO 3 H, or a metal salt thereof, and p is an integer of from 1 to 4, q, r, s, t and u are each an integer of from 0 to 4, and q+r=p and s+t+u=p.
Claim 4
Dependent Claim
62 words
The selective permeable membrane as in claim 1 wherein R 1 is a group represented by the formula ##STR31## R 2a and R 2b are each independently a methyl group or a phenyl group, R 3 is a group represented by the formulae ##STR32## and R 4 is selected from the groups represented by the formulae ##STR33## or a metal salt thereof.
Claim 5
Dependent Claim
27 words
A selective permeable membrane as in claim 1 wherein the unit (Ib) constitutes 70 mol % or less of the total of the units (Ia) and (Ib).
Claim 6
Dependent Claim
28 words
A selective permeable membrane as in claim 4 wherein the unit (Ib) constitutes from 5 to 60 mol % of the total of the units (Ia) and (Ib).
Claim 7
Dependent Claim
27 words
A selective permeable membrane as in claim 3 wherein the unit (Ib) constitutes 70 mol % or less of the total of the units (Ia) and (Ib).
Claim 8
Dependent Claim
28 words
A selective permeable membrane as in claim 6 wherein the unit (Ib) constitutes from 5 to 60 mol % of the total of the units (Ia) and (Ib).
References Cited (Backward Citations)
US4354017A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1988-07-15 | 1989-01-14 | 1989-07-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-07-15 | 1993-01-14 | 1993-07-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-07-15 | 1997-01-14 | 1997-07-16 | $7700.00 | Window Closed / Lapsed |