| 摘要 |
PURPOSE:To realize a diaphragm which features a high sound velocity and a large internal loss, by using the substance in which the graphite is combined with the organic binder resin for the diaphragm material. CONSTITUTION:The substance in which the natural or artificial graphite is combined with the organic binder is used for the diaphragm material. The composition ratio between the graphite and the binder resin is preferably set to 40-95% in weight for the amount of the graphite to the entire diaphragm. If the amount of the graphite is less than 40%, the sufficiently high speed cannot be obtained for the high sound speed diaphragm and with reduction of the internal loss. On the other hand, an amply large internal loss is obtained when the content of graphite is >85%. However, contrarily the strength is lowered to produce a brittle diaphragm. In such way, the production becomes possible for a diaphragm which features a higher sound velocity than the Al diaphragm as well as a similar degree of loss to the paper. |
