CPC C07C 263/10 (2013.01) [B29D 11/00009 (2013.01); C08G 18/3876 (2013.01); C08G 18/73 (2013.01); C08G 18/755 (2013.01); C08G 18/7642 (2013.01); G02B 1/041 (2013.01)] | 8 Claims |
1. A process for preparing a diisocyanate composition, which comprises:
(1) reacting a diamine composition with an aqueous hydrochloric acid solution to obtain a diamine hydrochloride composition;
(2) adding a first organic solvent to obtain the diamine hydrochloride composition in a solid phase; and
(3) reacting the diamine hydrochloride composition obtained in step 2 with triphosgene to obtain a diisocyanate composition,
wherein the diisocyanate composition has a b* value according to the CIE color coordinate of 0.1 to 2.0.
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