Cationic dyes according to application properties and chemical structure of two classification categories. According to the performances of China's existing dyes are divided into ordinary-type, x-type and m-type. According to the chemical structure is based on the dye molecules in cationic charge and dye chromophore of conjugated forms divided into isolated and conjugated two ways.
(1) isolation of cationic dyes: dye molecules are in charge by isolating the radicals and dye chromophore of conjugated systems connected to positive charge is fixed on the Quaternary nitrogen atoms. Characteristics of cationic dyes are for the color is a little lower, coloured light is not very bright, but heat, drying, acid and alkali, the stability is good. For example, cationic red GTL (C.I. Basic Red 18 (C.I.11085) (English name Cationic Red GTL),
Conjugate-type cationic dye: dye molecules in the positive charge is part of dye chromophore of conjugated system, positive charge are not fixed on an atomic, you can move domains. Azo dyes are characterized by bright, colourability, but light fastness of medium. For example, cationic yellow X-6G (C.I.48056) (English name Catinic Yellow X-6G).