US3276989A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Cation permselective membranes and process for the production thereof
Assignee: Individual
•
Filing: 1961-07-24
•
Granted: 1966-10-04
•
Expires: 1981-07-24
Abstract
No abstract record available.
Inventors
- 👤 Nishihara Akira
- 👤 Oda Yoshio
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 16:14
CPC Classifications
C; C08; C08J; C08J5/00; C08J5/20; C08J5/22; C08J5/2287; C08G; C08G8/00; C08G8/04; C08G8/08; C08G8/24; C08J2353/00; C08J2353/02
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
135 words
A PROCESS FOR THE PRODUCTION OF CATION PERMSELECTIVE MEMBRANES HAVING SPECIALLY LOW PERMEABILITY TO POLYVALENT CATIONS, COMPRISING IMPREGNATING A REINFORCING MATERIAL WITH A COPOLYMER LATEX OF MONOVINYL AROMATIC, HYDROCARBON AND CONJUGATED ALIPHATIC POLYENE COMPOUND, THE ACID MONOVINYL AROMATIC HYDROCARBON BEING 20 TO 75% OF THE COPOLYMER, DRYING THE IMPREGNATED MATERIAL TO FORM A MEMBRANE OF THE SAID COPOLYMER, CONTACTING THE THUS-OBTAINED MEMBRANE WITH CONCENTRATED SULFURIC ACID IN ORDER TO SULFONATE AND SIMULTANEOUSLY TO CONVERT THE COPOLYMER INTO AN INSOLUBLE, INFUSIBLE STRUCTURE OF A SYNTHETIC SOLID POLYMERIC MATRIX AND DISSOCIABLE SULFONIC GROUP BONDED CHEMICALLY TO THE MATRIX, COATING THE SURFACE OF THE THUS-OBTAINED BASE MEMBRANE WITH A VISCOUS LIQUID OF LOW MOLECULAR CONDENSATION PRODUCT WHICH IS PRODUCED BY COPOLYCONDENSING IN ALKALINE AQUEOUS SOLUTION (1) AT LEAST ONE OF THE COMPOUNDS REPRESENTED BY THE FOLLOWING GENERAL FORMULA,
Claim 2
Dependent Claim
135 words
A PROCESS FOR THE PRODUCTION OF CATION PERMSELECTIVE MEMBRANES HAVING SPECIALLY LOW PERMEABILITY TO POLYVALENT CATIONS, COMPRISING IMPREGNATING A REINFORCING MATERIAL WITH A COPOLYMER LATEX OF MONOVINYL AROMATIC, HYDROCARBON AND CONJUGATED ALIPHATIC POLYENE COMPOUND, THE ACID MONOVINYL AROMATIC HYDROCARBON BEING 20 TO 75% OF THE COPOLYMER, DRYING THE IMPREGNATED MATERIAL TO FORM A MEMBRANE OF THE SAID COPOLYMER, CONTACTING THE THUS-OBTAINED MEMBRANE WITH CONCENTRATED SULFURIC ACID IN ORDER TO SULFONATE AND SIMULTANEOUSLY TO CONVERT THE COPOLYMER INTO AN INSOLUBLE, INFUSIBLE STRUCTURE OF A SYNTHETIC SOLID POLYMERIC MATRIX AND DISSOCIABLE SULFONIC GROUP BONDED CHEMICALLY TO THE MATRIX, COATING THE SURFACE OF THE THUS-OBTAINED BASE MEMBRANE WITH A VISCOUS LIQUID OF LOW MOLECULAR CONDENSATION PRODUCT WHICH IS PRODUCED BY COPOLYCONDENSING IN ALKALINE AQUEOUS SOLUTION (1) AT LEAST ONE OF THE COMPOUNDS REPRESENTED BY THE FOLLOWING GENERAL FORMULA,
References Cited (Backward Citations)
US804176A
Cited
US2636851A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1969-10-03 | 1970-04-04 | 1970-10-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1973-10-03 | 1974-04-04 | 1974-10-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1977-10-03 | 1978-04-04 | 1978-10-04 | $7700.00 | Window Closed / Lapsed |