PURPOSE: To enable quick and easy bonding of parts without heating unnecessary parts, by passing a magnetic field energy through the bonding face between bonding objects and converting the magnetic energy into heat generated by eddy current loss, thereby melting and vulcanizing the resin at the surface of the bonding objects, accelerating the reaction and evaporating the solvent.

CONSTITUTION: A part A to be bonded (e.g. carpet face material) 4 and a part B (e.g. carpet backing) 5 are supplied through respective feeding rolls 10, 12 and an electrically conductive heat-generation material 1 is supplied with a feeding roll 11 between the parts 4 and 5. The sheets are laminated with tension rolls 13, 14 and a high-frequency current is passed through an electromagnetic induction-heating coil 3 to generate magnetic field. The magnetic field energy passed through the parts is converted to heat generated by eddy current loss by an dielectric heat-generation material 1 to effect the melting, vulcanization, acceleration of reaction and evaporation of solvent in the resin on the surface of the bonding object to obtain adhesive surfaces. The adhesive parts are bonded with each other and wound with a winding rill 15 to obtain a composite product composed of the parts A and B bonded with each other.