| abstract |
A low-volatile flame retardant for styrene resin comprising aromatic phosphoester of formula (I), wherein a, b, and c are integer of 1 to 3; R1, R2 and R3 respectively are hydrogen or alkyl having from 1 to 30 carbon atoms and not containing halogen and not as isopropyl, the average carbon number of substitution groups R1, R2 and R3 of the aromatic phosphoester per molecule is in the range of 12 to 25, but when the flame retardant contains a plurality of aromatic phosphate ester with different substitution groups, the total number of carbon atom of substitution groups R1, R2 and R3 in the retardant is expressed by the total average number in the retardant which is the total of the weight percentage of each aromatic phosphoester times the total carbon atoms of the substitution group in the respective aromatic phosphoester. |