Carbazole Violet Pigments

The quinacridone pigments are represented on the HPV Ust of substances that require review under SIDS protocol. Again, it would appear likely that sufficient data, much of it currently unpublished, will be available to avoid significant and costly mammalian toxicity testing for the quinacridone pigments represented on the Ust. 

Carbazole violet pigments, like most of the other organic pigments types, may possibly contain chlorinated trace contaminants, at part per bUUon levels, which may be included in the finished pigments. These trace contaminants are established PBT substances. Therefore, if a manufacturer or importer has sufficient information to estimate the total amount of PBT substances present at trace levels, then that manufacturer or importer would be required to assess and if necessary submit a TRI emission form to EPA. 

EPA recently published a Proposed Significant New Use Rule, which if finalized as proposed, could require the notification to EPA for products produced from chloranil, particularly if those products are produced from chloranil containing more than 20 ppb incidented dioxin and furan concentrations measured as Tetrachloro Dibenzodioxin Threshold Equivalency Quotient (TEQ). 

The perylenes were not found to be PBTs under CEPA. The ITC recently published a voluntary data submission list for 58 Potentially Persistent Dyes and Pigments . This list, which indicates that the ITC is considering a TSCA data collection under TSCA Section 8, includes two perylene pigments. The ITC is reviewing many chemicals that do not appear on the HPV lists for possible risk and PBT characteristics. The end result of this process did not require mandatory information gathering rules under TSCA for both perylene and quinacridone pigments. 

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Dioxazine. Carbazole Violet (Pigment Violet 23) is a bluish violet pigment that is uncommonly strong, resistant to solvents, and shows fair weatherfastness. It is used primarily as a shading pigment with copper phthalocyanines and for toning whites in a variety of systems. 

One such pigment is Carbazole Violet, Pigment Violet 23 (XXXIX) (52) synthesized as shown in Scheme XV. It is a brilliant violet... 

The principle of each process is briefly described ia the Hterature (170). Some anthraquiaoae dyes and pigments appear to be used ia combination with other dye or pigment classes such as phthalocyaniaes and carbazole violets, etc. Two examples described ia pateats are the red pigment and blue dye that foUow ... 

Other chemical types of high-performance organic pigments are exemplified by the tetrachloroisoindolinone 222 (C. I. Pigment Yellow 110) and the dioxazine 223 (Carbazole Violet, C. I. Pigment Violet 23). Considerable research has been carried out in an attempt to exploit the potential of metal complex chemistry to provide high-performance pig-... 

Most pigments derived from vat dyes are structurally based on anthraquinone derivatives such as indanthrone, flavanthrone, pyranthrone, or dibromoan-thanthrone. There are other polycyclic pigments which may be used directly in the form in which they are manufactured. This includes derivatives of naphthalene and perylene tetracarboxylic acid, dioxazine (Carbazole Violet), and tetrachloro-thioindigo. Quinacridone pigments, which were first introduced in 1958, and recently DPP pigments have been added to the series. 

P.V.23, 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). 

Carbazole Violet. These pigments are chloranil-derived compounds. In 1991, the EPA investigated the manufacture and use of these pigments as they and their precursors were suspected of being carcinogenic. No further action has been taken to date as a result of this investigation. 

H-Carbazole. See Carbazole Carbazole violet. See Pigment violet 23 Carbazotic acid. See Picric acid Carbendazim... 

As part of a general program to improve performance characteristics of the traditional carbazole dioxazine pigment in such areas as bleed resistance, solvent fastness and heat stability, and at the same time to extend the range of shades beyond violet, a new class of dioxazine pigment bearing quinoxalinedione and benzimidazo-lone moieties in place of carbazole residue has been developed at Clariant (Figure 20-14). By simple manipulation of the substituents on the heterocyclic... 

Benzimidazolone-dioxazine pigments identified for commercialization thus far are red-violet to reddish-blue in shade. They are characterized by an exceptionally high tinting strength, and their heat stability and resistance to aggressive solvents and plasticizers is much superior to that of carbazole dioxazine pigments. 

Permanent Violets n (1) A light resistant, tungstated or molybdated methyl violet pigment used in printing inks. (2) Carbazole violet. 

Purple Pigments. Methyl violet is the most commonly used purple pigment. It is also widely used for toning black inks. In packaging, although very expensive, Carbazole and Vat violets are used where permanence and resistance properties are needed. 

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