In the manufacture of parts such as rubber gaskets, it is common practice to reinforce the rubber material with a sheet of another or a reinforcing material such as metal or a high temperature melting plastic. Moreover, it is known to provide an adhesive bond between the rubber and the other material to form a composite sheet which combines the characteristics of both materials.
It has been found that a chemical bond between the rubber and the reinforcing material may break down in certain applications when subjected to certain extreme conditions. For example, when such a composite structure is used to form a gasket for an automobile headlamp, the adhesive (chemical) bond between the rubber and the metal reinforcement may break down under the heat generated by the headlamp. Since the forces applied to such bond are primarily in shear, a breakdown of the adhesive bond can result in significant damage to the gasket.
Accordingly, there is a need to provide a mechanical bond for composite articles wherein rubber is adhered to a reinforcing material, and to provide a mechanical bond which generally resists shear forces which would otherwise tend to break down a chemical bond (i.e. an adhesive joinder) between the materials.