PROBLEM TO BE SOLVED: To enhance the drying efficiency and the sterilizing effect of hydrogen peroxide by evenly blowing drying air to a cup conveyed by a retainer.SOLUTION: A cup 1 having a flange 3 is supported by a retainer 9, and after blowing the mist or the gas of hydrogen peroxide to inner and outer surfaces of the cup, the drying air b is blown to the cup to dry hydrogen peroxide. In this case, a cup opening part is covered by a covering plate 22 having a circumferential edge 22a for forming a space Q in the height direction of the cup in a space from the flange of the flange supported by the retainer, and a supply opening 22b smaller than a cup opening in the center, and the drying air is blown into the cup from the supply opening to dry hydrogen peroxide. Thus, the inner and outer surfaces of the cup are favorably sterilized, and hydrogen peroxide is dried and removed from the inner and outer surfaces of the cup.
