Patent ID: 7323096

Claim:
A method for surface treatment of an article to be treated such that a reaction vessel capable of accommodating an article to be treated and treating the surface thereof, and a separation vessel capable of separating a contaminant in a vapor phase surface treatment fluid are interposed in a surface treatment fluid circulation path, surface treatment fluids are introduced into the reaction vessel, surface treatment is performed, and thereafter, the surface treatment fluid in the reaction vessel is separated into vapor and liquid, the vapor phase surface treatment fluid is introduced into the separation vessel, and a contaminant is separated therefrom in the separation vessel, wherein a supercritical or subcritical surface treatment fluid and/or liquid surface treatment fluid is selectively introduced into the reaction vessel, surface treatment is performed, and thereafter, the surface treatment fluid in a vapor-liquid mixture state discharged from the reaction vessel is introduced into a treatment fluid recovery vessel, the surface treatment fluid is separated into vapor and liquid in the treatment fluid recovery vessel, and the separated vapor phase surface treatment fluid is refluxed to the circulation path.