| 摘要 |
PURPOSE:To obtain a lightweight, high-elasticity speaker diaphragm by laminating a composite layer consisting of propylene resin and a flat inorganic filler and a proplylene resin layer having metal vapor-deposited on one surface. CONSTITUTION:Propylene resin pellets containing the flat inorganic filler are made into a sheet with 0.4mm. thickness at 240 deg.C by using an extruder which has a T die. When the fused sheet from the T-die is passed between a couple of metallic rolls whose surfaces are finished into specular surfaces so that the thickness of the sheet is 0.4mm., the proplylene resin is passed between the metallic roll and fused sheet at the same time to obtain a sheet on which the proplylene resin layer is laminated. This laminated sheet is treated at 180 deg.C sheet surface temperature by using a vacuum forming machine to manufacture the speaker diaphragm. |
