Process for producing a water-absorbent resin
AssigneeSeitetsu Kagaku Co., Ltd.
InventorsMorio Nakamura, Shigeji Obayashi, Takushi Yamamoto, Toshikazu Nakanishi, Hitoshi Tanaka, Yuji Sakamoto
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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.
Claims10
A process for producing a water-absorbent resin wherein an aqueous solution of an .alpha.,.beta.-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 as a colloid agent, a saccharose-fatty acid ester having an HLB of 2 to 16 in an amount of 0.1 to 10% by weight based on the total of the .alpha., .beta.-unsaturated carboxylic acid and the alkali metal salt thereof, the fatty acid component of the saccharose-fatty acid ester being 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 being at least one selected from mono-, di-, and tri-.
Dependencies are inferred from the claim text.