| abstract |
(57) [Abstract] [Purpose] There is no contamination on the membrane surface, there is almost no decrease in water permeability, there is no safety problem due to dyes and impurities, and the location of the leak can be identified and the membrane defect can be repaired. A method for detecting defects in a permeable membrane is provided. In a method for detecting a defect of a reverse osmosis membrane using a dye solution, a food dye that is not adsorbed on the reverse osmosis membrane is used as a dye, and the food dye is adsorbed and ion exchange is performed as a means for detecting the dye leaked from the defect. A method for detecting defects in a reverse osmosis membrane, which comprises using a porous sheet-like material having an ability. |