PROBLEM TO BE SOLVED: To provide washing water having high stability, and having effect of sterilizing and washing bacteria and viruses by producing high concentration of hypochlorous acid at the time of washing.SOLUTION: In an aqueous solution containing hypochlorous acid and hypochlorite ions produced by diaphragmless electrolysis, its effective residual chlorine concentration is adjusted from 500 ppm to 2,000 ppm, and its hydrogen ion concentration index is adjusted from pH 8.5 to pH 9.5 to prepare washing water exhibiting high sterilization and washing effect at the time of use while maintaining long-term stability.SELECTED DRAWING: Figure 2
