| 摘要 |
PURPOSE:To improve acoustic characteristics and make construction stable and rigid as well as to reduce variations of characteristics and deformation with time against humdity, etc. by adhering a metal plate to a specific thermoplastic resin molding by way of a non-drying tacky material. CONSTITUTION:A thermoplastic resin material such as polymethyl methacrylate is injection-molded, whereby the molding composed of a core layer having expanded at expansion rates 1.05 to 1.80 and a skin layer covering said core layer is molded to wall thicknesses 6 to 30mm. A non-drying tacky material such as a mixture of natural rubber, rosin, wax and ZnO is coated on the abovementioned molding or metal plate material. Or the one which has beforehand been fabricated to sheet form is affixed. The thickness thereof is desirably 30 to 500mu. Next, the metal plate is joined to the molding and the laminate is compression bonded. |
