PURPOSE: To obtain inexpensively the titled compound capable of keeping an aqueous solution of galactomannan at high viscosity free from reduction in viscosity caused by decomposition, by reacting galactomannan with an alkylene oxide in a galactomannan suspension to which a nitrogen-containing basic substance is added.
CONSTITUTION: In a suspension obtained by adding (D) a nitrogen-containing basic substance (e.g., ammonia, etc.) to a mixture of (A) a hydrophilic organic solvent (preferably acetone, etc.), (B) water, and (C) galactomannan, the component C is reacted with (E) an alkylene oxide (e.g., ethylene oxide, etc.) in an amount to give preferably 0.1W2mol based on unit anhydro saccharide of the component C usually at 30W100°C, and the reaction product is dried, to give the desired compound. A weight ratio of the component A to the component B is preferably (30:70)W(95:5).
EFFECT: When it is dissolved in water, powdery particles will not cause solid granulation and a high-quality compound with low ash is obtained.
TABUCHI TAKU
KOBAYASHI MASAO
MITSUBISHI RAYON CO