Modified wool and process of imparting shrink-proofing property to wool

Modified wool having improved shrink-proofing property is obtained by a two step process in which raw material wool is first immersed in a first aqueous bath containing a water-soluble organic phosphine and is then immersed in a second aqueous bath containing a modifying agent selected from epoxy compounds, ethyleneimine compounds, urea, substituted urea compounds, thiourea, substituted thiourea compounds, alkylene carbonates, unsaturated carboxylic acids, derivatives of unsaturated carboxylic acids, unsaturated nitriles, unsaturated alcohols, esters of an unsaturated alcohol, sulfonic acid salts having a vinyl group, cyanic acid salts, nonionic surfactants of a poly(alkylene oxide) type, salts of sulfates of the nonionic surfactants and silane coupling agents having a vinyl group. The treatment may also be performed by a one step process in which wool is immersed in an aqueous bath containing the above phosphine compound and a modifying agent selected from the above.