PURPOSE: To obtain the titled ether having a stable aqueous solution viscosity and being capable of holding a high aqueous solution viscosity, by directly drying a reaction product between an alkylene oxide and a mixture of galactomannan, a basic substance and water.
CONSTITUTION: A reaction product obtained by reacting an alkylene oxide with a mixture containing galactomannan, a basic substance and water under high- speed agitation is directly dried. Of the basic sustances which can be used, ammonia, organic amines, and quaternary ammonium salts not only allow the reaction to proceed satisfactorily but also are easily evaporated in a step for drying the product just after the reaction, so that, these organic amines have an advantage of being recovered and recirculated. As it is possible to adopt a method in which the reaction product is dried without subjecting it to treatments such as neutralization or purification, the process can be shortened markedly. For example, it is possible to adopt a metho in which the reaction product is cast into film which is then dried and ground.
TABUCHI TAKU
KOBAYASHI MASAO
MITSUBISHI RAYON CO