PURPOSE: To prepare a methyl sulfoethyl cellulose which has very high solution quality and is useful as thickners, dispersants or binders with minimum amount of an etherifying agent by alkalizing cellulose and etherifying in the presence of a base or a catalyst.
CONSTITUTION: (a) Cellulose is alkalized by reacting with an alkali, preferably in an inert organic solvent, in the presence of a compound which transfers alkyl groups. Next, (b) the alkali cellulose is etherified in the presence of a base using at least one etherifying agent requiring at least catalyst quantity of a base. Thereby, a sulfoethyl cellulose which has a degree of substitution (DS) by sulfoethyl groups, substituting at least one substituent, typical of cellulose derivatives of below 0.4, especialy below 0.35 is obtained.
RUNE KIIZEBETSUTAA
KURAUSU SUZABURIKOUSUKI
