ARTICLE HAVING METALLIC SURFACE, TONE-TREATMENT METHOD THEREFOR, AND GAS PHASE OXIDATION DEVICE

The present invention improves rubbing fastness after a tone treatment has been performed on an article having a base material where at least the surface is composed of copper-zinc alloy. The presentinvention also provides a tone-treatment device that makes it possible to keep the amount of water used lower than with a wet treatment. Provided is an article having a base material 11 where at leastthe surface is composed of a copper alloy containing zinc, and an oxide layer 12 adjacent to the base material 11 surface, a ratio A of the mean zinc concentration to the mean copper concentration ina range of the depth of 10 to 20 nm with reference to the oxide layer 12 surface being higher than a ratio B of the mean zinc concentration to the mean copper concentration in the base material 11 surface. Also provided is a gas phase oxidation device for carrying out a tone-treatment method, the gas phase oxidation device being provided with: a gas phase reaction chamber 115 having an entrance and an exit and carrying out