these sites. Thus, the metal can form a ternary complex on whichone site binds with the fiber and the other site binds with the dye(Bhattacharya and Shah, 2000). Stannous chloride and aluminumpotassium sulfate form weak coordination complexes with dye;they tend to form quite strong bonds with the dye but not with thefiber, so they block the dye and reduce the dye interaction with thefiber (Bhattacharya and Shah, 2000).