PROCESS FOR SOLIDIFICATION OF PHOSPHORIC ESTER FLAME RETARDANTS

摘要

The invention provides a process for the solidification of a phosphoric ester flame retardant which can dispense with high purification and stress load. The invention relates to a process for the solidification of a phosphoric ester flame retardant which comprises adding 1 to 50 parts by mass of seed crystals at 55°C or below to 100 parts by mass of one or more phosphoric esters of the general formula (I) which are in a molten state: (I) [wherein R1 and R2 are each independently hydrogen or methyl; and n is a number of 1 to 5]. It is preferable that the content of phosphoric esters of the general formula (I) wherein n is 1 be less than 90% by mass and R1 and R2 be hydrogen.