RADICAL POLYMERIZATION CONTROL AGENT AND RADICAL POLYMERIZATION CONTROL METHOD

The radical polymerization control agent contained in a radical polymerizable composition of the present invention functions as a radical polymerization inhibitor for example stored in a dark place, but loses its radical polymerization inhibiting effect when polymerization is initiated while being irradiated with light at a certain specific wavelength at the time of polymerization. Thus, radical polymerization of the radical polymerizable compound is easily initiated without increasing the amount of a radical polymerization initiator. That is, the radical polymerization control agent of the present invention is a radical polymerization control agent which is a corn pound having an effect to inhibit radical polymerization of a radical polymerizable compound and which loses the radical polymerization inhibiting effect under irradiation with light rays containing light within a wavelength range of from 300 nm to 500 nm.