| 摘要 |
PROBLEM TO BE SOLVED: To provide a sapphire material-cleaning method allowing simple and effective cleaning of a sapphire material with gas-dissolving water obtained by dissolving a low-cost and safe gas.SOLUTION: In a cleaning method where a sapphire material is cleaned by contacting the sapphire material with a cleaning liquid, the cleaning liquid is nitrogen gas-dissolving water and a supersonic wave is applied in cleaning. The pH of the nitrogen gas-dissolving water is preferably greater than 7. The concentration of the nitrogen gas in the nitrogen gas-dissolving water is preferably 8 mg/L to 20 mg/L. After alkaline cleaning of the sapphire material, it is preferable to clean with the nitrogen gas-dissolving water. |
