PREPARATION OF SEMICONDUCTOR TREATING SOLUTION

摘要

PURPOSE:To obtain a high-purity choline aqueous solution excellent in stability in operation and maintenance, by a method wherein trimethylamine aqueous solution and ethylene oxide aqueous solution are introduced into a reactor at the same time and mixed together so as to be uniformly dispersed to react. CONSTITUTION:Trimethylamine aqueous solution containing one or more mols of trimethylamine with respect to one mol of ethylene oxide, and ethylene oxide aqueous solution or liquid ethylene oxide are introduced into a reactor at the same time. Then, they are rapidly mixed together so as to be uniformly dispersed to react. The time to bring them into the state promptly is preferably shorter than one fifth of the time required to reach the highest temperature of the mixing reaction (generally 30-60 deg.C in case of mixing both the solutions having ordinary temperatures).