PROBLEM TO BE SOLVED: To provide a surface treatment method for bringing out an excellent surface treatment effect by performing a coating treatment on the powder surface without using additive or dispersant, or by suppressing the used amount, and a powder on which a coating treatment is preformed by the method, and furthermore a cosmetic containing the surface-treated powder.SOLUTION: Such a method is accomplished by irradiating plasma to a powder in water, as pre-treatment of surface treatment of the powder. That is, the pre-treatment is performed by having the configuration of the electrodes to generate plasma to be such that the one of the pair electrodes be in a state submerged in water, or be in contact with water surface, and the other electrode be in a state placed in the air above water surface, and by applying a high voltage between both electrodes to generate plasma. Also, in this pre-treatment by plasma, the powder is in water and is in a state in which the powder surface is coated with water.COPYRIGHT: (C)2014,JPO&INPIT【課題】添加物や分散剤を使わない、又はその使用量を抑えて、粉体表面に被覆処理を施して優れた表面処理効果を引き出すための表面処理方法、及びその方法で被覆処理された粉体、さらには、その表面処理粉体を含有する化粧料を提供する。【解決手段】粉体の表面処理の前処理として、水中の粉体にプラズマを照射する。すなわち、プラズマを発生させる電極構成が、一対の電極のうち、一方の電極は水中に入れた、又は水面に接触した状態とし、他方の電極は水面上部の気中に配置された状態とし、この両電極間に高電圧を印加してプラズマを発生させ前処理を行う。また、このプラズマによる前処理では、粉体は水中にあり、粉体表面が水に覆われた状態である。【選択図】図1
