| abstract |
Provided are: a powder composition suitable for forming, by melt extrusion, films having excellent dielectric characteristics and having adhesion, processability, and low linear expansion; and a film suitable for use as a material for printed wiring boards.　The powder composition comprises a powder of a tetrafluoroethylene-based polymer including a unit based on a perfluoro(alkyl vinyl ether) or a unit based on hexafluoropropylene, a powder of an inorganic filler having a Mohs hardness of 3-9, and a powder of a thermoplastic aromatic polymer. The film comprises these ingredients and at least has a sea-island structure composed of a sea phase, which includes the aromatic polymer, and an island phase, which includes the tetrafluoroethylene-based polymer. |