US4042496A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for preparing improved cation-exchange membranes
Assignee: Asahi Kasei Corp
•
Filing: 1975-05-28
•
Granted: 1977-08-16
•
Expires: 1995-05-28
Abstract
Abstract An improved cation-exchange membrane, onto which have been adhered fine particles of a crosslinked high molecular weight substance having anion-exchange groups and which can maintain a specific permselectivity for monovalent cations over a long period of time, is prepared with ease by treating a cation-exchange membrane with a suspension of fine particles of the said crosslinked high molecular weight substance.
Inventors
- 👤 Sakae Tsushima
- 👤 Teruyuki Misumi
- 👤 Masahiko Murakoshi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 04:03
CPC Classifications
C; C08; C08J; C08J5/00; C08J5/20; C08J5/22; C08J5/2287; C08J2339/00; C08J2339/04; C08J2339/08; C08J2453/00; C08J2453/02
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
49 words
A process for improving a cation-exchange membrane in specific permselectivity for monovalent ions which comprises contacting the cation-exchange membrane with a suspension, in water or in an aqueous solution of a salt containing said monovalent ions, of particles of a crosslinked high molecular weight substance having an anion-exchange group.
Claim 2
Dependent Claim
49 words
A process for improving a cation-exchange membrane in specific permselectivity for monovalent ions which comprises contacting the cation-exchange membrane with a suspension, in water or in an aqueous solution of a salt containing said monovalent ions, of particles of a crosslinked high molecular weight substance having an anion-exchange group.
Claim 3
Dependent Claim
19 words
A process for electrolyzing sodium chloride by use of a cation-exchange membrane treated with the process of claim 1.
Claim 4
Dependent Claim
39 words
A process according to claim 1, wherein the crosslinked high molecular weight substance is a compound prepared by converting into a quaternary ammonium salt a copolymer composed of a basic nitrogen-containing vinyl compound monomer and a polyvinyl compound monomer.
Claim 5
Dependent Claim
35 words
A process according to claim 2, wherein the cation-exchange membrane is a membrane prepared from a quaternary ammonium salt of a copolymer composed of a basic nitrogen-containing vinyl compound monomer and a polyvinyl compound monomer.
Claim 6
Dependent Claim
25 words
A process for treating water containing lower and higher molecular weight substances with use of a cation-exchange membrane treated with the process of claim 1.
Claim 7
Dependent Claim
40 words
A process as in claim 1 wherein the particles have the following characteristics: 1. exchange capacity: at least 0.5 m. equiv/g (dry), 2. particle diameter: up to 10.0 microns, 3. degree of crosslink: 0.0 to 10% based on bifunctional monomer.
Claim 8
Dependent Claim
15 words
A process as in claim 5 wherein the particles are based on quaternary ammonium salt.
Claim 9
Dependent Claim
26 words
A process as in claim 1 wherein the concentration of polymer particles in the suspension is from 1 to 50 grams of dry resin per liter.
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) | 1980-08-15 | 1981-02-14 | 1981-08-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-08-15 | 1985-02-14 | 1985-08-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-08-15 | 1989-02-14 | 1989-08-16 | $7700.00 | Window Closed / Lapsed |