To provide a liquor vessel from which the dissolution of Fe is inhibited, by modifying the passive film so as to substancially consist of Cr.
The liquor vessel made from a stainless steel comprises the stainless steel for a base material and the passive film inside the vessel, which Fe concentration is reduced to 30 atomic % or lower and which mainly consists of oxide or hydrate of Cr. The passive film is formed by means of selectively dissolving Fe component from the passive film till the Fe concentration of the passive film is decreased to 30 atomic % or less, through contacting the inner surface of the vessel to an acid rinse/washings including an organic acid, after the stainless steel was formed into liquor vessel shape. The acid rinse/ washings includes one kind or two kinds of the group consisting of citric acid, lactic acid, malic acid, and succinic acid, for the organic acid, and is preferably prepared to pH of 3.0-4.5 and a solution temperature of 50°C.
ADACHI TOSHIRO
NAGOSHI TOSHIRO
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