Abstract: The product is a laminar composite of two or more adhesively bonded layers of sheet material, one of which has a corrugated surface contour at the interface between the layers. The layers are bonded together at the ridges of the corrugated surface of the one layer, and the bond on each ridge consists essentially of a series of relatively localized spots of a plastically deposited but adhesively set adhesive material. The spots are located at intervals spaced apart from one another lengthwise of the ridge, and are characterized with oblate cross sections in planes normal to the interface between the layers, resulting from the fact that the spots undergo compression in the plastic state thereof during the process. The bonding operation is accomplished by causing relative motion between the corrugated web and a series of spaced parallel lines of adhesive material which are disposed crosswise of the ridges of the web and contacted with the ridges so as to deposit the spots thereon.