Abstract
The colorants were extracted from black soybean using a buffer solution. Dyeing properties and the fastness of silk fabric dyed with black soybean extracts were investigated. K/S values of dyed fabric were increased with concentration of black soybean extracts. Magnesium sulfate, nickel sulfate and calcium chloride as mordants are used to obtain reddish purple color. Optimum dyeing temperature of black soybean extracts was $30^{\circ}C$. Fastness were generally good except for light fastness which was extremely poor.