quinone imine dyes that are derivatives of oxazine (I). The most widely used oxazine dyes are the direct ones—light and dark blue in color—and those that are used as pigments—violet in color. The latter are prepared by condensation of chloranil (II) with aromatic or heterocyclic amines. Direct oxazine dyes are obtained by simultaneous condensation and sulfonation processes.
The important oxazine dyes—direct blue 107 (III), which is used in dyeing cotton fabric, and violet dioxazine pigment (IV)—are highly durable.