CPC H01G 9/07 (2013.01) [H01G 9/045 (2013.01); H01G 9/055 (2013.01); H01G 9/145 (2013.01); H01G 9/15 (2013.01)] | 10 Claims |
1. An electrode foil for an electrolytic capacitor, the electrode foil comprising:
a metal foil having a porous part; and
a dielectric layer covering a surface of a metal framework constituting the porous part, wherein:
the dielectric layer includes a first layer containing an oxide of a second metal different from a first metal contained in the metal framework, the first layer having a thickness T1,
the first layer contains at least one kind of additive element selected from the group consisting of carbon, phosphorus, boron, and nitrogen,
the first layer has an inner surface and an outer surface, the inner surface facing the metal framework, the outer surface being opposite to the inner surface,
the at least one kind of additive element is contained in a region from the outer surface of the first layer to a depth of at least 0.05×T1,
the first layer includes a first region and a second region, the first region being from the outer surface to a center of the first layer in a thickness direction, the second region being from the center to the inner surface, and
a content of the at least one kind of additive element in the first region is greater than a content of the at least one kind of additive element in the second region.
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