A phosphorous-containing compound is represented by Formula (I): ##STR00001## wherein n is an integer ranging from 1 to 4; R.sup.1 represents hydrogen or a linear or branched C.sub.1-C.sub.4 alkyl group, and a plurality of R.sup.1s are the same or different when n is larger than 1; R.sup.2 represents hydrogen, ##STR00002## or ##STR00003## wherein Ep is an epoxy resin moiety; or ##STR00004## represents ##STR00005## wherein Ar represents a linear or branched C.sub.1-C.sub.12 alkyl group or a C.sub.6-C.sub.12 aryl group; and R.sup.3 represents hydrogen or methyl. |