abstract |
METHOD FOR PREVENTING COLORATION OF AROMATIC ISOCYANATE COMPOUNDS ABSTRACT OF THE DISCLOSURE A method for preventing coloration of an aromatic isocyanate compound, which is characterized in that an organic phosphite ester of formula: wherein R1, R2, R3 and R4 are, the same or different, each a C4-20 hydrocarbon group, 2,6-di-tert.-butyl-4-methylphenol and triphenyl phos-phite are added to the aromatic isocyanate compound. |