| 摘要 |
PROBLEM TO BE SOLVED: To provide a cleaning agent and cleaning method for the inner face of a copper tube, capable of effectively removing a carbon coating formed on the inner face of a copper tube while suppressing damages on the inner face of a copper tube to maintain durability.SOLUTION: A cleaning agent for the inner face of a copper tube is used for removing a carbon coating formed on the inner face of a copper tube, and includes an aqueous solution of organic acid, sulfamic acid or a chelating agent and an oxidizing agent, as active ingredients to remove the carbon coating. The organic acid is preferably citric acid, the chelating agent is preferably an ethylenediaminetetraacetic acid salt such as ethylenediaminetetraacetic acid sodium. The oxidizing agent is preferably hydrogen peroxide, or percarbonate such as sodium percarbonate. |
