DIAPHRAGM FOR ELECTROACOUSTIC TRANSDUCER

摘要

PURPOSE:To improve both specific elastic modulus and internal loss, by mixing a filler into thermoplastic resin to increase the Young's modulus and at the same time obtaining a lamination structure with the resin having a high internal loss. CONSTITUTION:Polypropylene is kneaded with the flaky mica powder underwent a epoxy silane coupling process and the flaky graphite powder underwent a titanate coupling process to obtain the 1st film of 220mum thickness by an extrusion molding process. While mixture resin of styrene-isoprene-styrene block copolymer, petroleum resin and atactic polypropylene is sliced by 150mum thickness to obtain the 2nd film. The 1st film is set on both sides of the 2nd film, and the 2nd film is fused and adhered with pressure to the 1st film. Thus a composite sheet of 500mum thickness containing an outer layer formed from the 1st film on both sides of a 60mum thickness intermediate layer formed from the 2nd film is obtained. This composite sheet is used to a diaphragm.