Dioxazine properties

To obtain the necessary fastness properties, high-quality pigments are generally used for security printing. The range of suitable products covers disazo, disazo condensation, benzimidazolone, naphthol AS, isoindolin, perinone, anthanthrone, dioxazine and quinacridone pigments. 

Although very few detailed studies have been carried out, the acid-base properties of polyheteroatom six-membered rings are fairly predictable. The fully reduced systems behave as typical secondary amines, although the inclusion of extra heteroatoms often reduces their basicity. Thus the reduced dithiazines (68) (thialdine) and (69), and the related thiadiazine (70), are weak bases with pKz values of 2.7, 2.8 and 2.0 respectively (58JCS2893). The weak basicity is due to the inductive effect of the /3-heteroatoms. This inductive effect of /3-heteroatoms is also apparent in the dioxazine (71), which exhibits no tendency to... 

PY 153 Nickel dioxazine Red shade excellent fastness properties poor acid resistance... 

Dioxazines, Oxathiazines, and Dithiazines Table 1 Some physical properties of various dioxa-, oxathia- and dithiazines. 

CAS 6358-30-1 EINECS/ELINCS 228-767-9 Synonyms Carbazole violet Cl 51319 8,18-Dichloro-5,15-diethyl-5,15-dihydrodiindolo [3,2-b 3, 2 -m] triphenodioxazine Dioxazine violet RL Classificatbn Oxazine color Empirical Cs4H22Cl2N402 Properties M.w. 589.49 Toxicology TSCA listed... 

Imidazolone-annellated triphenedioxazine pigments, also called benzimidazo-lone-dioxazine pigments, are a relatively new class of violet pigments with very good fastness properties and extremely high color strengths. The stractural formula is shown in Figure 20.1. 

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