Composite sheets of acoustic insulation - consists of layer of foam adhering to layer of heavier mixt. of tacky resin dispersion and water absorbing e.g. mineral filler

摘要

A composite material, and sound insulation in partic., has a layer of foam bonded to a heavier layer which consists of a permanently tacky dispersion of a synthetic resin such as a copolymerised acrylic ester and a water-absorbing binder. The heavier layer can contain e.g. cement or plaster as the water-absorbing material, this takes up water liberated when the acrylic resin hardens off. By making the content of the filler appropriate this dispenses with need to dry out the prod. The prod. can have several layers altogether. ADVANTAGE - The method of prodn. is efficient and the prod. has good acoustic properties. The prodn. requires no drying process and it can make large size sheets. The heavier layer can be heavily filled, e.g. with e.g. barytes or quartz sand to obtain a surface gravity of greater than 2. This layer can be applied to any desired places. It can also be filled partic. with e.g. metallic fillers for specific purposes.