VIBRATION DAMPING MATERIAL AND SLIDING PAET AND ACOUSTIC INSTRUMENT PART USING THE MATERIAL

摘要

PURPOSE:To provide a vibration damping material having excellent vibration- damping performance, mechanical properties, sliding properties, etc., at room temperature or thereabout and high sound velocity and capable of imparting the vibration and noise suppressing and reducing effect to sliding parts such as bearing and gear and acoustic instrument parts such as speaker diaphragm and speaker cabinet. CONSTITUTION:This vibration damping material is produced by mixing (A) 10-100 pts.wt. of a vinyl acetate-ethylene copolymer having a vinyl acetate content of >=70mol% with (B) 100 pts.wt. of a thermoplastic resin. This material has high loss coefficient tan delta representing the vibration damping performance and remarkably high flexural modulus compared with conventional damping material. It has high sound velocity and the sliding characteristics of the material is sufficiently improved by impregnating an oil in the material. Accordingly, the material is suitable also as a sliding part such as bearing and gear. When the material is used as a material for acoustic instrument, the sound quality can be improved in addition to the prevention of vibration and noise because the reverberation is quickly attenuated by the use of the material.