PURPOSE: To obtain an excellent acoustic characteristic whose heat resistance, solvent resistance and rigidity are improved by using graphite for a foaming core member.
CONSTITUTION: The title diaphragm has a foaming core member 21 and a skin member 22 provided on at least one of the front face and the rear face of the foaming core member 21 and the graphite is used at least for the foaming core member 21. Consequently, the manufacturing efficiency of the diaphragm can be improved, various deformations, etc., in a manufacturing process can be prevented and the heat resistance, the solvent resistance and the rigidity can be improved. Thus, the excellent acoustic characteristic can be realized. Further, by molding the graphite integrally, lightening and the unification of weight can be attained and the manufacturing efficiency is more improved.
OKUZAWA KAZURO
OKAZAKI MASATOSHI
