| 摘要 |
Disclosed is an energy conversion film having a high ability to convert energy, wherein a porous resin film having a high expansion ratio is obtained by forming a thermoplastic resin stretched film having a specific structure even without employing an expansion treatment with high-pressure gas so that a larger amount of electric charge can be held due to pores in the inside of the film. The energy conversion film (i) comprises a core layer (A) composed of a thermoplastic resin stretched film containing a thermoplastic resin and at least one of an inorganic powder and an organic filler, and is characterized in that the core layer (A) contains pores having a height in the film thickness direction through the observation of the cross-section in the thickness direction of 3 to 30 µm and having a diameter in the film plane direction of 50 to 500 µm at a density of 100 to 3,000 pores/mm2. |
