Method for manufacturing resin film for thin film-capacitor and the film therefor

Abstract

The present invention provides a resin film for a film capacitor making it possible to obtain the excellent heat resistance, materialize a reduction in a size of the film capacitor and an increase in a capacity thereof and satisfy a reduction in a thickness of the film and a high voltage resistance thereof. In a manufacturing method in which an extruding equipment 10 is charged with a molding material 1 to extrude a film 2 for a film capacitor from a T die 20, in which the above extruded film 2 for a film capacitor is interposed between plural rolls in a receiving device 30 and cooled and in which the above cooled film 2 for a film capacitor is wound on a winding tube 42 of a winding device 40 , 100 parts by mass of a polyetherimide resin is blended with 1 to 10 parts by mass of a fluorocarbon resin to prepare the molding material 1; the above molding material 1 is extruded through a filter 50 having apertures 51 which are 0.5 to 6 times or less as large as an average thickness of the film. 2 for a film capacitor, which is provided between the extruding equipment 10 and the T die 20; and a thickness of the film 2 for a film capacitor is controlled to 10 pm or less.

1 - 2 . (canceled) 
     
     
         3 . A film for a film capacitor manufactured by a method comprising the steps of:
 charging an extruding equipment with a molding material to extrude a film for a film capacitor from an extruding die and interposing the extruded film between plural rolls to cool the extruded film, wherein:   100 parts by mass of at least a polyetherimide resin is blended with 1 to 10 parts by mass of a fluorocarbon resin to prepare the molding material;   the molding material is extruded through a filter having apertures which are 0.5 to 6 times or less as large as an average thickness of the extruded film the filter being provided between the extruding equipment and the extruding dice de;   the thickness of the extruded film is controlled to 10 pm or less; and   the method excludes biaxial stretching.