Pigment Yellow Solvent Blue

Although treated as separate classes in the Colour Index, these structural types are closely related and the few diphenylmethane dyes such as auramine (1.28 Cl Basic Yellow 2) are now of little practical interest. Commercial usage of the triarylmethane dyes and pigments has also declined considerably in favour of the major chemical classes. They were formerly noteworthy contributors to the acid, basic, mordant and solvent ranges, primarily in the violet, blue and green sectors. Numerous structural examples are recorded in the Colour Index. The terminal groupings can be amine/quinonimine, as in auramine and crystal violet (1.29 Cl Basic Violet 3), hydroxy/quinone, or both. The aryl nuclei are not always benzenoid (section 6.5). 

P.Y.12 and considerably more so in comparison with P.Y.13. A number of the P.Y.14 types are appreciably greener than the standard yellow on the European Scale. P.Y.14 is not only weaker than comparable P.Y.13 varieties with similar physical characteristics, such as specific surface area but it is also less lightfast by 1 to 2 steps on the Blue Scale. Its resistance to solvents is also comparatively poor. This somewhat limits its use for process inks in offset and letterpress application to special cases, which is equally true for P.Y.14 blends with reddish pigments. Types with fine particle sizes, which match highly transparent versions of P.Y.12 and 13, are not available in Europe. 

P.O.38 is broad in scope. The list of applications includes special media, such as wax crayons, artists colors, and wood stains, including those that are solvent based. The products are very lightfast (step 7 on the Blue Scale) and fast to overcoating. Blends of P.O.38 with yellow pigments, such as P.Y.83 or P.Y.120, or with carbon black produce useful shades of brown. 

Apart from these areas of application, P.V.32 is also used in solvent-based wood stains. The lightfastness of the products equals step 6 on the Blue Scale, which is very good. These systems may safely be overcoated. Pigment blends with yellow pigments, such as with P.Y.83, and blends with black provide interesting shades of brown. 

Solvent dyes are really intermediate between dyes and pigments being insoluble in water but soluble in solvents, especially hydrocarbons. Structurally many solvent dyes bear a close similarity and relationship with disperse dyes. The Colour Index has an issne on Solvent Dyes, where several hundred dyes are described, unfortunately many of the strnctnres remain confldential. The structures of the disclosed dyes range from very simple monoazo dyes, e.g. Cl Solvent Yellow 14 (2.78) to the higher performing anthraquinones, e.g. Cl Solvent Yellow 163 (2.79) and Blue 36 (2.80), quinophthalones... 

Molybdic acid anhydride Molybdic anhydride Molybdic oxide Molybdic trioxide Natural molybdite NSC 216191. Source of Mo reagent for analytical chemistry agriculture manufacture of metallic molybdenum corrosion inhibitor ceramic glazes enamels pigments catalyst. Yellow-blue powder mp = 795° bp = 1155° 4.696 soluble in H2O (0.49 g/l), insoluble in organic solvents LDso (rat orl) = 2689 mg/kg, AAA Molybdenum Atomergic Chemetals Cerac Climax Molybdenum Co. 

PCBs and PCDDs. In Diarylide Yellow manufacture, the use of formate buffer to enhance pigment transparency for offset ink was discontinued in the nineteen seventies, when it was realized that polychlorinated biphenyls were being produced as an undesirable by-product of the coupling reaction. In Phthalocyanine Blue crude synthesis, the commonly used solvent, trichlorobenzene, was also discontinued in the US, as a potential source of poly-chlorinated biphenyls. More recently, use of chloranil, manufactured from chlorinated phenols, has been discontinued in the synthesis of dioxazine violet crude and sulfonated dioxazine acid dyes, so as to minimize by-product formation of polychlorinated dibenzodioxins and dibenzofurans (PCDDs/PCDFs). A new grade ofhigh purity chloranil is now produced from hydroquinone for dye and pigment manufacture. 

Disperse blue 72 Pigment red 122 Solvent green 3 Solvent green 28 Solvent red 111 Solvent red 135 Solvent violet 13 Solvent yellow 93 Solvent yellow 160 colorant, PVC... 

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