SOUND ABSORBING AND INSULATING MATERIAL AND ITS PREPARATION

摘要

PROBLEM TO BE SOLVED: To provide a sound absorbing and insulating material which can ensure both sound absorbing properties and sound insulating properties by integral molding without bonding together a plurality of materials and its method for preparation. SOLUTION: After a molten resin prepd. by plasticizing fiber-contg. thermoplastic resin pellets contg. specified reinforcing fiber is injected into a mold, a cavity is expanded by retreating a movable core to expand the molten resin by a spring-back phenomenon. Interstice layers 43 provided with excellent sound absorbing properties by a number of interstices and skin layers 41 and 42 with high density and high rigidity and provided with excellent sound insulating properties are integrally formed thereby. Then, when the skin layer 41 on one side is removed, a sound absorbing and insulating material 2A in which both sound absorbing properties and sound insulating properties are ensured is obtd. even by integral molding of the same material.