Alston & Bird LLP
Anodic oxide coating, treatment method therefor, and piston for internal combustion engine
Provided are an anodic oxide coating for an aluminum-based material, a treatment method therefor, and a piston for an internal combustion engine, the anodic oxide coating having both high heat insulation properties and high corrosion resistance, high durability and high impact resistance, and high water-repellent and oil-repellent functions. The treatment method includes the steps of: forming a second anodic oxide coating 2b by application of AC-DC superimposition electrolysis to an aluminum-based material 1; and, after the step, forming a first anodic oxide coating 2a by application of direct-current electrolysis to the aluminum-based material 1, wherein the second anodic oxide coating 2b is formed on the first anodic oxide coating 2a. 
SUZUKI MOTOR CORPORATION
C C C F C F
C25D C25D C25D F02F C25D F02F
inventional inventional inventional inventional inventional additional
Masahiro Haruhiko
Fujita Murakami