PURPOSE: To provide a rational method of producing a modified cellulose ether wherein a modifier reacts at a high efficiency and there is no need of using a large amount of an organic solvent and which therefore is economical and contributes to the prevention of working-atmosphere pollution.
CONSTITUTION: A water-soluble cellulose ether dispersed in an organic solvent is reacted with an epoxyalkane and/or an alkyl glycidyl ether each having an 8-24C alkyl in the presence of an alkali to replace the hydrogen atoms of part of the hydroxyl groups of the ether by the alkyl group, thereby giving a modified cellulose ether. The amount of the solvent is 0.5-3 times, preferably 0.5-1.0 time, by weight the amount of the ether. The reaction is conducted in a reactor equipped with a stirrer having two rotating blades 2. The ether is preferably hydroxypropylmethyl cellulose and/or hydroxyethyl cellulose.
MINEMURA KATSUYOSHI
MARUYAMA KAZUMASA
MUTO YASUAKI
