US4306031A
Expired / Lapsed
US
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Weakly acidic cation exchange resin and process for producing same
Assignee: Mitsubishi Chemical Corp
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Filing: 1980-08-04
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Granted: 1981-12-15
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Expires: 2000-08-04
Abstract
Abstract A weakly acidic cation exchange resin which is obtainable by a reaction of glyoxylic acid and a polyvinyl alcohol cross-linked by cross-linking groups each containing two or more carbon atoms, and has an exchange capacity of 3 meq/g or greater and a swelling volume of 10 ml/g or smaller, as well as a process for producing such cation exchange resin.
Inventors
- 👤 Takaharu Itagaki
- 👤 Hidenaga Ouchi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 18:01
CPC Classifications
B; B01; B01J; B01J39/00; B01J39/08; B01J39/16; B01J39/18; B01J39/20; C; C08; C08F; C08F8/00; C08F8/48; C08F2810/00; C08F2810/20
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
64 words
A process for producing a weakly acidic cation exchange resin which comprises bringing a polyvinyl alcohol into reaction with a cross-linking reagent capable of forming cross-linking groups each containing two or more carbon atoms to form a cross-linked polyvinyl alcohol and bringing said cross-linked polyvinyl alcohol into reaction with glyoxylic acid in the presence of a mineral acid and a water soluble inorganic salt.
Claim 2
Dependent Claim
64 words
A process for producing a weakly acidic cation exchange resin which comprises bringing a polyvinyl alcohol into reaction with a cross-linking reagent capable of forming cross-linking groups each containing two or more carbon atoms to form a cross-linked polyvinyl alcohol and bringing said cross-linked polyvinyl alcohol into reaction with glyoxylic acid in the presence of a mineral acid and a water soluble inorganic salt.
Claim 3
Dependent Claim
13 words
The process as defined in claim 1, wherein said cross-linking reagent is glutaraldehyde.
Claim 4
Dependent Claim
13 words
The process as defined in claim 1, wherein said cross-linking reagent is epichlorohydrin.
Claim 5
Dependent Claim
87 words
A process for producing a weakly acidic cation exchange resin which comprises: suspending an aqueous solution containing a cross-linking reagent capable of forming cross-linking groups each containing two or more carbon atoms, a polyvinyl alcohol and a water soluble inorganic salt, into a dispersing medium thereby making said cross-linking reagent react with said polyvinyl alcohol to form a porous cross-linked polyvinyl alcohol and; bringing said porous cross-linked polyvinyl alcohol into reaction with glyoxylic acid in the presence of a mineral acid and a water soluble inorganic salt.
Claim 6
Dependent Claim
87 words
A process for producing a weakly acidic cation exchange resin which comprises: suspending an aqueous solution containing a cross-linking reagent capable of forming cross-linking groups each containing two or more carbon atoms, a polyvinyl alcohol and a water soluble inorganic salt, into a dispersing medium thereby making said cross-linking reagent react with said polyvinyl alcohol to form a porous cross-linked polyvinyl alcohol and; bringing said porous cross-linked polyvinyl alcohol into reaction with glyoxylic acid in the presence of a mineral acid and a water soluble inorganic salt.
Claim 7
Dependent Claim
13 words
The process as defined in claim 4, wherein said cross-linking reagent is glutaraldehyde.
Claim 8
Dependent Claim
13 words
The process as defined in claim 4, wherein said cross-linking reagent is epichlorohydrin.
Claim 9
Dependent Claim
115 words
A process for producing a weakly acidic cation exchange resin which comprises: forming an aqueous solution in which a cross-linking reagent capable of forming cross-linking groups each containing two or more carbon atoms and a polyvinyl alcohol are dissolved and fine particles of water-insoluble inorganic salt are dispersed; suspending said aqueous solution into a dispersing medium thereafter making said cross-linking reagent react with said polyvinyl alcohol to form a cross-linked polyvinyl alcohol containing said fine particles of water-insoluble inorganic salt therein; removing said water-insoluble inorganic salt from said resulted cross-linked polyvinyl alcohol and; bringing said cross-linked polyvinyl alcohol into reaction with glyoxylic acid in the presence of a mineral acid and a water-soluble inorganic salt.
Claim 10
Dependent Claim
115 words
A process for producing a weakly acidic cation exchange resin which comprises: forming an aqueous solution in which a cross-linking reagent capable of forming cross-linking groups each containing two or more carbon atoms and a polyvinyl alcohol are dissolved and fine particles of water-insoluble inorganic salt are dispersed; suspending said aqueous solution into a dispersing medium thereafter making said cross-linking reagent react with said polyvinyl alcohol to form a cross-linked polyvinyl alcohol containing said fine particles of water-insoluble inorganic salt therein; removing said water-insoluble inorganic salt from said resulted cross-linked polyvinyl alcohol and; bringing said cross-linked polyvinyl alcohol into reaction with glyoxylic acid in the presence of a mineral acid and a water-soluble inorganic salt.
Claim 11
Dependent Claim
13 words
The process as defined in claim 7, wherein said cross-linking reagent is glutaraldehyde.
Claim 12
Dependent Claim
13 words
The process as defined in claim 7, wherein said cross-linking reagent is epichlorohydrin.
Claim 13
Dependent Claim
120 words
A process for producing a weakly acidic cation exchange resin which comprises: forming an aqueous solution in which a cross-linking reagent capable of forming cross-linking groups each containing two or more carbon atoms and a polyvinyl alcohol are dissolved and fine particles of water-insoluble inorganic salt are dispersed; suspending said aqueous solution in a dispersing medium thereafter making said cross-linking reagent react with said polyvinyl alcohol to form a cross-linked polyvinyl alcohol containing said fine particles of water-insoluble inorganic salt therein; bringing said cross-linked polyvinyl alcohol thus formed into reaction with glyoxylic acid in the presence of a mineral acid and a water soluble inorganic salt and; removing said water-insoluble inorganic salt contained in the inside of the reaction products.
Claim 14
Dependent Claim
120 words
A process for producing a weakly acidic cation exchange resin which comprises: forming an aqueous solution in which a cross-linking reagent capable of forming cross-linking groups each containing two or more carbon atoms and a polyvinyl alcohol are dissolved and fine particles of water-insoluble inorganic salt are dispersed; suspending said aqueous solution in a dispersing medium thereafter making said cross-linking reagent react with said polyvinyl alcohol to form a cross-linked polyvinyl alcohol containing said fine particles of water-insoluble inorganic salt therein; bringing said cross-linked polyvinyl alcohol thus formed into reaction with glyoxylic acid in the presence of a mineral acid and a water soluble inorganic salt and; removing said water-insoluble inorganic salt contained in the inside of the reaction products.
Claim 15
Dependent Claim
13 words
The process as defined in claim 10, wherein said cross-linking reagent is glutaraldehyde.
Claim 16
Dependent Claim
13 words
The process as claimed in claim 10, wherein said cross-linking reagent is epichlorohydrin.
Claim 17
Dependent Claim
15 words
The product of the process of any one of claims 1, 4, 7, and 10.
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) | 1984-12-14 | 1985-06-15 | 1985-12-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-12-14 | 1989-06-15 | 1989-12-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-12-14 | 1993-06-15 | 1993-12-15 | $7700.00 | Window Closed / Lapsed |