Aishibu dyeing is a very time-consuming and advanced dyeing technique that involves dyeing the fabric a bright indigo blue and then layering it with persimmon tannin. The color is deeper than ordinary indigo dyeing, and the more you use it, the stronger the persimmon tannin color becomes. Kakishibu is also used as a Chinese herbal medicine and is said to have high antibacterial and deodorizing properties