| abstract |
In an embodiment, in the process of preparing diisocyanate from diamine through diamine hydrochloride, an aqueous hydrochloric acid solution may be used instead of hydrogen chloride gas and solid triphosgene may be used instead of phosgene gas. In addition, the embodiment provides a method for producing a diisocyanate composition and an optical lens having excellent yield and quality while reducing environmental problems by controlling the total content of cations in the diamine hydrochloride composition within a specific range. |