| 摘要 |
PURPOSE:To obtain a speaker having a flat frequency characteristics, by mixing mica flakes into a thermoplastic synthetic resin as reinforcing material. CONSTITUTION:For example, polypropylene, polyethylene, polybutene, polybutadiene, methylpentene, etc. are suitable as the thermoplastic synthetic resin for this purpose, and average diameter of the mica flakes to be mixed to the synthetic resin can be selected out of a range from <=20->=1,400mu depending on the specification of a desired vibration diaphragm. To mix the mica flake into the thermoplastic resin, a mixer having a low shearing force is used to prevent breakage of the mica flake. To make reinforcing effectively, the interface between the mica flake and the synthetic resin is brought into strongly sticked. The mixture is molded to the shape of a vibration diaphragm by vacuum or air-pressure molding after the mixture is formed to a film by extrusion molding at first, or the mixture is directly molded to a diaphragm by injection molding, etc. |
