PURPOSE: To prepare easily, surely, with good reproducibility, inexpensively and efficiently a vibration-damping composite material wherein a resonance circuit with a specified vibrational period, a leakage circuit or an electric circuit being close to these circuits is constituted inside and a vibration with a specified vibrational period or a period being close to the vibrational period is attenuated by means of this electric circuit.
CONSTITUTION: A composite functional particle 4 is prepd. by coating the surface of a piezoelectric particle 1 having a relatively large particle diameter with both an electrically conductive particle or a semiconductive particle 2 having a relatively small particle diameter and a particle 3 of the third ingredient having a small particle diameter and the composite functional particle 4A is dispersed in a polymer matrix 5. In another method, a composite functional particle is prepd. by coating the surface of a piezoelectric particle having a relatively large particle diameter with an electrically conductive particle or a semiconductive particle having a relatively small particle diameter and then, a particle of the third ingredient having a small particle diameter and the composite functional particle is dispersed in a polymer matrix.
KIDOGUCHI AKIRA
INABA TOSHIHARU
