Commercially Available Dioxazine Pigments and Their Application

The three-dimensional crystal structure of Pigment Violet 23 (117) elucidates molecular staples whereby the stables of the single molecular planes are arranged in an almost perpendicular orientation to each other. Interactions of the -ir-orbitals as well as van der Waals forces are responsible for the cohesion of the structure. The degree of overlapping is especially high in the dioxazine part of the molecule [3], 

4 Commercially Available Dioxazine Pigments and Their Application 

At present, this class produces only two representatives which continue to be used industrially Pigment Violet 23,51319 (117) and Pigment Violet 37,51345 (117a)  

While P. V.23 is used in considerable volume, P.V.37 is a specialty product. Pigments of the P.V.34 and 35 type, which are much inferior in terms of tinctorial strength and sometimes also migration fastness, especially in plastics, have been discontinued several years ago. These compounds typically contained ethoxyani-line with acetylamino or benzoylamino moieties instead of the carbazole group of P.V.23 [7-9], 

also referred to as Carbazole Violet, is a universally useful product. Its color, a bluish violet shade, is not accessible with other Pigments. P.V.23 is used in almost all media which are typically colored with pigments. The list of suitable systems ranges from coatings and paints to plastics, printing inks, and other special-purpose media. P.V.23 is entirely fast to many organic solvents. At standardized conditions (Sec. 1.6.2.1), it is fast to alcohols, esters, and aliphatic hydrocarbons as well as to plasticizers such as dibutyl and dioctyl phthalate. Other solvents, such as ketones, are colored slightly (step 4). 

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