| 摘要 |
PROBLEM TO BE SOLVED: To provide a method of removing metal impurities, which can remove efficiently metal impurities adhering to experimental instruments made of a fluororesin, etc. in a short time.SOLUTION: An ultrasonic cleaning of an acid solution in which an object to be cleaned made of the fluororesin is immersed is carried out in a warming state. Further, the method comprises a first cleaning process of immersing the object to be cleaned made of the fluororesin in a first acid solution to carry out the ultrasonic cleaning in the warming state, and a second cleaning process of immersing the object to be cleaned made of the fluororesin which finishes the first cleaning process in a second acid solution to carry out the ultrasonic cleaning in the warming state. |
