| abstract |
PURPOSE: To prepare the stable titled emulsion capable of forming coating film with excellent water-resistance, by emulsifying a polyurethane resin containing blocked isocyanate groups using an anionic reactive surface active agent. n CONSTITUTION: A blocked isocyanate group-containing polyurethane resin wherein the terminal isocyanate group is blocked with a blocking agent, is dispersed and emulsified in water using 3W50wt%, based on the resin, of an anionic reactive surface active agent of formula [R is 7W26C alkyl, alkenyl, or 8W22C fatty acid residue; X is O, CO, COO, S, or NR' (R' is polyalkylene oxide or 1W22C alkyl); l is 0W200; m and n are 1W4 and m+n≤5; A is organic polyisocyanate residue]. By the thermal treatment of the emulsion, the blocking groups of both urethane resin and surface active agent are dissociated, and the components are incorporated in the same structure by the generated isocyanate groups. Consequently, a film free from ionic hydrophilic groups in the structure can be obtained without using an external emulsifier. n COPYRIGHT: (C)1981,JPO&Japio |