wherein R1 and R2 each represent an organic group or a halogen atom, and m and n each represent an integer of 0 to 4, and when m or n is an integer of 2 to 4, R1 and R2 may be the same or different, and A represents an organic group that is the same as or different from R1 and R2; and a thermoplastic resin, wherein the thermoplastic resin composition for masterbatches contains a phosphorus conten