EP0176664A1
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Process for producing a water-absorbent resin
Assignee: Sumitomo Seika Chemicals Co Ltd
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Filing: 1985-05-29
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Granted: —
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Expires: 2005-05-29
Abstract
Abstract A water-absorbent resin usable as a suitable water absorbent in sanitary materials and other fields can be produced by subjecting an aqueous solution of an alpha , beta -unsaturated carboxylic acid and of an alkali metal salt thereof to polymerization with a radical polymerization initiator in a petroleum-based hydrocarbon solvent in the presence or absence of a crosslinking agent and, in this polymerization, using a saccharose-fatty acid ester as a protective colloid agent.
Inventors
- 👤 Morio Nakamura
- 👤 Shigeji Obayashi
- 👤 Takushi Yamamoto
- 👤 Toshikazu Nakanishi
- 👤 Hitoshi Tanaka
- 👤 Yuji Sakamoto
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-08 12:16
CPC Classifications
C; C08; C08F; C08F20/00; C08F20/02; C08F20/04; C08F20/06; A; A61; A61L; A61L15/00; A61L15/16; A61L15/42; A61L15/60; C08F2/00; C08F2/32
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
58 words
A process for producing a water-absorbent resin wherein an aqueous solution of an α,β-unsaturated carboxylic acid and of an alkali metal salt thereof is subjected to polymerization with a radical polymerization initiator in a petroleum-based hydrocarbon solvent in the presence or absence of a crosslinking agent, characterized by using a saccharose-fatty acid ester as a protective colloid agent.
Claim 2
Dependent Claim
58 words
A process for producing a water-absorbent resin wherein an aqueous solution of an α,β-unsaturated carboxylic acid and of an alkali metal salt thereof is subjected to polymerization with a radical polymerization initiator in a petroleum-based hydrocarbon solvent in the presence or absence of a crosslinking agent, characterized by using a saccharose-fatty acid ester as a protective colloid agent.
Claim 3
Dependent Claim
14 words
A process according to Claim 1, wherein the α,8-unsaturated carboxylic acid is acrylic acid.
Claim 4
Dependent Claim
35 words
A process according to Claim 1, wherein the petroleum-based hydrocarbon solvent is one member or a mixture of at least two members selected from the group consisting of n-hexane, n-heptane, cyclohexane, benzene, toluene and xylene.
Claim 5
Dependent Claim
13 words
A process according to Claim 3, wherein the petroleum-based hydrocarbon solvent is n-heptane.
Claim 6
Dependent Claim
14 words
A process according to Claim 1, wherein the radical polymerization initiator is potassium persulfate.
Claim 7
Dependent Claim
12 words
A process according to Claim 1, wherein the crosslinking agent is N,N-methylenebisacrylamide.
Claim 8
Dependent Claim
15 words
A process according to Claim 1, wherein the crosslinking agent is ethylene glycol diglycidyl ether.
Claim 9
Dependent Claim
23 words
A process according to Claim 1, wherein the protective colloid agent is a saccharose-fatty acid ester having a HLB of 2 to 16.
Claim 10
Dependent Claim
57 words
A process according to Claim 8, wherein the saccharose-fatty acid ester is such that the fatty acid component is at least one member selected from the group consisting of stearic acid, palmitic acid, lauric acid and oleic acid and the number of esters per unit of saccharose is at least one selected from mono-, di- and tri-.
Claim 11
Dependent Claim
16 words
A process according to Claim 9, wherein the saccharose-fatty acid ester consists mainly of saccharose distearate.
Claim 12
Dependent Claim
18 words
A process according to Claim 9, wherein the saccharose-fatty acid ester consists mainly of saccharose di- and tristearates.
Claim 13
Dependent Claim
18 words
A process according to Claim 9, wherein the saccharose-fatty acid ester consists mainly of saccharose mono- and distearates.
Claim 14
Dependent Claim
37 words
A process according to Claim 1, wherein the saccharose-fatty acid ester is used in an amount of 0.1 to 10% by weight based on the total of the α,β-unsaturated carboxylic acid and the alkali metal salt thereof.
References Cited (Backward Citations)
DE3210513A1
Cited
GB2104904A
Cited
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