Functional dyes have special functions or special specialty, Their special functions usually depend on modern high and new technologies involving photo, electric, heat, chemical and biochemical property. This type of dyes absorbs tin energy and gives special functions, so featuring low consumption, high price and good economic benefit.

So far functional dyes have been widely used in some hi-tech fields like liquid crystal display, temperature sensitive and pressure sensitive recording, optical disc recording, photochemical catalysis, and photochemistry treatment. Japanese large dyes companies have regarded functional dyes as their development emphasis. While in China functional dyes, except for photo, Xerox and copy, have little use in other areas or still in trial production stage, without enough attention to be paid to. Especially functional dyes are just its initial stage in dyeing and finishing. The relevant research, manufacturing, application and management are far behind advanced countries. It can be said that functional dyes sector is worthy of the attention and efforts of dye operators and dyeing and finishing workers.