Process for foaming an adhesive using moisture in a backing

摘要

Adhesive laminates and their preparation. According to one embodiment, an adhesive laminate comprising a foamed pressure sensitive adhesive layer and a release liner applied thereto is prepared by applying hot pressure sensitive adhesive material in layer form to a release coated surface of a release paper or other release liner. Moisture is transferred from the release liner to the hot molten adhesive layer, causing the latter to foam. According to a second embodiment, a coextrudate comprising a thermoplastic carrier with an adhesive coating on one or both sides thereof is formed by the coextrusion of the adhesive taking place with the carrier over at least a short distance and at a temperature of about 350 DEG F.