Contact glue also known as contact cement are rubber based and can be made from natural or synthetic rubbers. These adhesives are very good for bonding veneer or plastic laminate to manufactured boards, for example for making kitchen cabinets. Contacting adhesives are harder to work with compared to other adhesives such as PVA glue because they require a great deal of accuracy. The adhesive is applied to both surfaces being bonded and is then left until touch dry. The two surfaces are then secured with some pressure and the bond is immediate and permanent. Contacting adhesives have great holding strength and don’t require clamps to hold the timber together.
Most contact glues used to be polychloroprene based but are now replaced by polyurethane (also see polyurethane glue for the environmental profile). Most are solvent based, although there are waterbased and even natural ones on the market.