Metal Solvent Dyes

Ink-Jet Dyes (see Section 5.6). Printing inks based on solvents such as methyl ethyl ketone or alcohol contain laked metallized solvent dyes, for example the statistically mixed 1 2 chromium complex 35 [60] ... 

The condensation on the fabric of 1-amino-3-iminoisoindo1enines or 2-amino-5-iminopyrro1enines with phloroglucinol, preferably in the presence of metal salts and solvents, yields fast dyeings in brown shades (158). Metallized azo dyes derived from phloroglucinol yield fast dyeings on leather (qv) or silk (qv) (159). 

By far the most important metal containing dyes are derived from OjO-dUiydroxyazo stmctures in which one of the two azo nitrogen atoms and the two hydroxyl oxygen atoms are involved in bonding with the metal ion. Thus these dyes serve as terdentate ligands. In the case of metal ions with a coordination number of four, eg, Cu(H), the fourth position is usuaUy occupied by a solvent molecule (47). 

Solvent dyes are used to colour the transparent paints used to exploit the special properties of metallic pigments, as mentioned earlier. Another use for solvent dyes is in the colouring of many plastic articles to supplement the colouring power of pigments, if the use of pigments alone in a particular application is found to have undesirable effects on the physical properties of the plastic. 

The new Colour Index volume Pigments and Solvent Dyes lists some 350 solvent dyes and gives their chemical structures, unlike earlier editions which named 800 dyes but included few structures. This fall in numbers is not because of any decreased use but rather the general contraction in numbers of all dyes used in the textile industry. Solvent dyes have been introduced not by attempts to synthesise new colorants but by selection and in some cases modification of known disperse dyes to meet the technical requirements. The majority of solvent dyes are azo compounds but among the blue dyes there are anthraquinones. The aqueous solubility of some of the parent sulphonated dyes has been reduced to acceptable levels by formation of their salts with heavy metals or long-chain alkylamines. 

Symmetrical premetallised 1 2 metal-dye complexes of unsulphonated monoazo structures with aluminium (5.57) or trivalent iron (5.58) have been patented recently for use as solvent dyes [36]. They contain a polar methoxypropylaminosulphone grouping in each diazo component and are marketed as alkylamine salts. It remains to be seen, however, whether a full colour gamut of bright aluminium and iron complex dyes can be discovered with light fastness performance equivalent to that of currently available chromium and cobalt complex dyes. 

Uses Preparation of 3,4-dichloroaniline solvent for a wide variety of organic compounds and for oxides of nonferrous metals solvent carrier in products of toluene diisocyanate intermediate for dyes fumigant insecticide for termites degreasing hides and wool metal polishes degreasing agent for metals, wood, and leather industrial air control disinfectant heat transfer medium. 

Solvent dyes [1] cannot be classified according to a specific chemical type of dyes. Solvent dyes can be found among the azo, disperse, anthraquinone, metal-complex, cationic, and phthalocyanine dyes. The only common characteristic is a chemical structure devoid of sulfonic and carboxylic groups, except for cationic dyes as salts with an organic base as anion. Solvent dyes are basically insoluble in water, but soluble in the different types of solvents. Organic dye salts represent an important type of solvent dyes. Solvent dyes also function as dyes for certain polymers, such as polyacrylonitrile, polystyrene, polymethacrylates, and polyester, in which they are soluble. Polyester dyes are principally disperse dyes (see Section 3.2). 

Solvent Dyes (see also Section 3.10). The 1 2 chromium and cobalt complex dyes devoid of any hydrophilic substituent have a considerable solubility in organic solvents, especially alcohols, ketones, and esters. Enhanced solubility can be achieved by converting the metal-complex sodium salts into salts of organic cations [57], Such cations may be cationic dyes, long-chain aliphatic ammonium ions, or protonated guanidines. For example, the bluish red solvent dye 34 reaches a solubility in organic solvents of up to 1000 g/L [58],... 

These laked 1 2 metal-complex dyes belonging to the generic class of solvent dyes have a broad application range, including transparent lacquers, wood stains, numerous office products, foil printing, and recently ink-jet printing [59],... 

Anionic dyes (brilliant acid dyes) and solvent dyes (unsulfonated metal-complex and other solvent-soluble dyes for brilliant shades) are used for shade correction. 

Most xanthene dyes are classified as basic dyes by their method of appHcation acid dyes can be produced by introduction of sulfonic acid groups. The fluoresceins, which contain carboxy and hydroxy substituents, are also acid dyes for coloration of sUk. Some of the fluoresceins in which the carboxy group has been esterified, are soluble in alcohol or other oiganic solvents and can be classified as solvent dyes. Mordant dyes can be produced by introducing o-dihydroxy or salicyhc acid groups (2), which when metallized can have very good lightfastness. 

Major uses include its use as a component of natural and synthetic resins metal solvent for formulation of soluble oils solvent for lacquers, lacquer thinners, dyeing, textiles, and varnish removers carrier for printing ink wafer fabrication process for semiconductor manufacturing and anti-icing additive for aviation fuels. 

MAJOR USES Used as raw materials for plastics, solvents, dyes, drugs, paints, pipe coatings, roads, roofing, pesticides, sealants, to produce hydrogen, to extract metal from their ores, to manufacture graphite and electrodes, coal tar used in treatment of skin disorders. 

ORIGIN/INDUSTRY SOURCES/USES manufacture of 3,4-dichloro-aniline solvent dyes fumigant and insecticide metal polishes industrial odor control, herbicides... 

For large metal complex dyes (>650Da), Feeder et al. [62] have demonstrated that intercellular diffusion of these materials occurs into wool fiber. Certain alcohols, such as butanols, are considered nonswelling solvents and have been shown by Jurdana and Leaver [63] not to penetrate into the cortex of wool but to penetrate readily into the cortex of human hair via the intercellular regions. 

Acetic acid is both a reactant and solvent in the manufacture of cellulose acetate, polyester fibers, and plastics. Other products that utilize acetic acid as a reactant include vinyl acetate, ester solvents, dyes, metallic salts, pharmaceuticals, and pesticides. Formic acid is used in textile dyeing and finishing, leather tanning and treatment, pharmaceuticals, and the synthesis of the versatile methyl formate solvent. n-Butanoic acid is used in the preparation of cellulose acetate butyrates used for lacquers and molding plastic compositions. The acid is also used for the production of useful coating ester solvents, plasticizers, and pharmaceuticals. 

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