| abstract |
In the process of preparing metha xylylene diisocyanate from methaxylylenediamine via methaxylylenediamine hydrochloride, the reaction conditions are controlled by using an aqueous solution of hydrochloric acid and an organic solvent instead of hydrogen chloride gas and a solid triphosphene instead of phosgene gas. Thus, there is provided a method for producing metha xylylene diisocyanate and optical lens which is excellent in yield and quality while having little environmental problems. |