| abstract |
The present invention manufactures a high-quality fine particle removal treatment water, which is used in ultra-pure water manufacturing process and the like, and has a primary amine group, a secondary amine group, a tertiary amine group, and a quaternary amine group. The MF membrane or UF membrane with any one or more functional groups in the ammonium group suppresses the influence caused by the functional groups introduced into the MF membrane or UF membrane when removing fine particles in water, and is suitable as an electronic part manufacturing step or a cleaning step The ultrapure water used. Before being used to remove fine particles, use an alkaline agent with a pH value of 9 or higher to clean the MF membrane or UF having any one or more functional groups of the primary amine group, the secondary amine group, the tertiary amine group, and the quaternary ammonium group The membrane is then used to remove fine particles. |