Film capacitor, and exterior case for film capacitor
A film capacitor that includes a capacitor element having a metallized film including a resin film and a metal layer on a surface of the resin film; an outer case that houses the capacitor element; and a filling resin that fills a space between the capacitor element and the outer case, wherein a surface free energy of an inner surface of the outer case in contact with the filling resin is 44 mN/m or less.
1. A film capacitor comprising:
a capacitor element having a metallized film including a resin film and a metal layer on a surface of the resin film;
an outer case that houses the capacitor element; and
a filling resin that fills a space between the capacitor element and the outer case,
wherein a surface free energy of an inner surface of the outer case in contact with the filling resin is 44 mN/m or less.
2. The film capacitor according to claim 1 , wherein the surface free energy is 34 mN/m or less.
3. The film capacitor according to claim 1 , wherein the surface free energy is 25 mN/m to 44 mN/m.
4. The film capacitor according to claim 1 , wherein a difference in coefficient of linear expansion between the outer case and the filling resin is 11 ppm/° C. or less.
5. The film capacitor according to claim 4 , wherein the difference in coefficient of linear expansion is more than 0 ppm/° C.
6. The film capacitor according to claim 1 , wherein the outer case is made of a resin composition.
7. The film capacitor according to claim 6 , wherein the resin composition contains a liquid crystal polymer.
8. The film capacitor according to claim 6 , wherein the resin composition contains polyphenylene sulfide.
9. The film capacitor according to claim 7 , wherein the resin composition further contains an inorganic filler, and an amount of the inorganic filler in the resin composition is 54 wt % or less.
10. The film capacitor according to claim 8 , wherein the resin composition further contains an inorganic filler, and an amount of the inorganic filler in the resin composition is 60 wt % or less.
11. The film capacitor according to claim 9 , wherein the amount of the inorganic filler in the resin composition is 30 wt % to 54 wt %.
12. The film capacitor according to claim 11 , wherein the inorganic filler contains a glass filler as a main component thereof.
13. The film capacitor according to claim 1 , wherein the outer case is made of a metal or an alloy.
14. The film capacitor according to claim 1 , wherein the filling resin contains an epoxy resin.
15. An outer case of a film capacitor, the outer case constructed to house a capacitor element having a metallized film including a resin film and a metal layer on a surface of the resin film, and to house a filling resin in a space between the capacitor element and the outer case, wherein a surface free energy of an inner surface of the outer case is 44 mN/m or less.
16. The outer case according to claim 15 , wherein the surface free energy is 34 mN/m or less.
17. The outer case according to claim 15 , wherein the surface free energy is 25 mN/m to 44 mN/m.
18. The outer case according to claim 15 , wherein the outer case is made of a resin composition.
19. The outer case according to claim 18 , wherein the resin composition contains a liquid crystal polymer.
20. The outer case according to claim 18 , wherein the resin composition contains polyphenylene sulfide.
21. The outer case according to claim 19 , wherein the resin composition further contains an inorganic filler, and an amount of the inorganic filler in the resin composition is 54 wt % or less.
22. The outer case according to claim 20 , wherein the resin composition further contains an inorganic filler, and an amount of the inorganic filler in the resin composition is 60 wt % or less.
23. The outer case according to claim 21 , wherein the amount of the inorganic filler in the resin composition is 30 wt % to 54 wt %.
24. The outer case according to claim 23 , wherein the inorganic filler contains a glass filler as a main component thereof.
25. The outer case according to claim 15 , wherein the outer case is made of a metal or an alloy.