Acid dyes phthalocyanine

Phthalocyanine sulfonic acids, which can be used as direct cotton dyes (1), are obtained by heating the metal phthalocyanines in oleum. One to four sulfo groups can be introduced in the 4-position by varying concentration, temperature, and reaction time (103). Sulfonyl chlorides, which are important intermediates, can be prepared from chlorosulfonic acid and phthalocyanines (104). The positions of the sulfonyl chloride groups are the same as those of the sulfonic acids (103). Other derivatives, eg, chlormethylphthalocyanines (105—107), / /f-butyl (108—111), amino (112), ethers (109,110,113—116), thioethers (117,118), carboxyl acids (119—122), esters (123), cyanides (112,124—127), and nitrocompounds (126), can be synthesized. 

Most reported phthalocyanine derivatives (sulfo-, nitro-, amino-, triphenylmethyl-, polymeric, etc.) are copper complexes, although at present the synthetic chemistry of other d- and /-metal Pc derivatives is being rapidly developed (Examples 30-36) [5,6,116-118]. Some of them (in particular, copper phthalocyanine sulfonic acids) are of industrial interest because of their usefulness as dyes. Phthalocyanine sulfonic acids themselves are prepared both by urea synthesis from sulfonated phthalic anhydride and by the sulfonation of the phthalocyanine [6], Some substituted metal phthalocyanines can be obtained by chemical or electrochemical reduction [118e]. Among a number of reported peculiarities of substituted phthalocyanines, the existence of three electronic isomers for magnesium derivative PcMn was recently confirmed [118f]. 

According to their chemical structures and the Cl system, dyes can be classified into 17 groups nitro dyes, triphenylmethane derivatives, xanthenes, acridine derivatives, quinoline derivatives, azines, ant-hraquinones, indigoid dyes, phthalocyanines dyes, oxydation bases, insoluble azo dye precursors, and azo dyes (classes XII-XVII). In practice, dyes are classified into different application classes disperse, acid, basic, direct, vat, fiber-reactive, sulfur, preme-tallic, solvent dyes, and naphthols. 

This consists of the phthalocyanine dyes, an example of this group being Coomassie Turquoise Blue 3G. This is a trisulphonated derivative of copper phthalocyanine. It dyes wool a very bright greenish blue shade. Its fastness to light is better than the triphenylmethane acid dyes which alone will give comparable shades. 

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. 

Salih Agirtas, M., MetinQelebi, Sel9ukGumus. (2013). New water soluble phenoxy phenyl diazenyl benzoic acid substituted phthalocyanine derivatives Synthesis, antioxidant activities, atypical aggregation behavior and electronic properties. Dyes and Pigments 99, 423 31. 

Phthalic anhydride. The feedstocks are either naphthalene or o-xylene, the process being a catalysed air oxidation (see Vol. I, pp. 293, 317, 368). The product is required in large quantities by the plastics industry, the intake in the dye industry being only minor in quantity. It is the feedstock for phthalocyanine production and in the synthesis of anthraquinone intermediates, e.g. quinizarin (for disperse dyes) and 2-methylanthraquinone (for acid dyes). 

Although acid dyes have been typically used for the coloration of ink jet inks, phthalocyanine pigments are now replacing these dyes, especially in industrial applications such as signs, advertisements and textiles, to improve the water resistance and light fastness. For cyan inks, C.l. Pigment Blue 15 3 and 15 4 have been used. 

There are some exceptions to this, e.g, the spectra in concentrated sulfuric acid of phthalocyanine pigments and certain vat dyes and the charge-resonance spectra of hepta- and higher polymethine-cyanines and of the beta-carotene-antimony trichloride complex [ ], all of which have peaks in the near infrared beyond 800 m/i. 

The phthalocyanines must be suitably dis-p>ersed to be used as pigments or they can be sulphonated to water-soluble forms for dyeing and for precipitation as lakes. The dispersion is carried out by solution in sulphuric acid, followed by precipitation in water. 

Phthalocyanine Dyes. In addition to their use as pigments, the phthalocyanines have found widespread appHcation as dyestuffs, eg, direct and reactive dyes, water-soluble dyes with physical or chemical binding, solvent-soluble dyes with physical or chemical binding, a2o reactive dyes, a2o nonreactive dyes, sulfur dyes, and wet dyes. The first phthalocyanine dyes were used in the early 1930s to dye textiles like cotton (qv). The water-soluble forms Hke sodium salts of copper phthalocyanine disulfonic acid. Direct Blue 86 [1330-38-7] (Cl 74180), Direct Blue 87 [1330-39-8] (Cl 74200), Acid Blue 249 [36485-85-5] (Cl 74220), and their derivatives are used to dye natural and synthetic textiles (qv), paper, and leather (qv). The sodium salt of cobalt phthalocyanine, ie. Vat Blue 29 [1328-50-3] (Cl 74140) is mostly appHed to ceUulose fibers (qv). 

Dyes and Pigments. Several thousand metric tons of metallated or metal coordinated phthalocyanine dyes (10) are sold annually in the United States. The partially oxidized metallated phthalocyanine dyes are good conductors and are called molecular metals (see Semiconductors Phthalocyanine compounds Colorants forplastics). Azo dyes (qv) are also often metallated. The basic unit for a 2,2 -azobisphenol dye is shown as stmcture (11). Sulfonic acid groups are used to provide solubiHty, and a wide variety of other substituents influence color and stabiHty. Such complexes have also found appHcations as analytical indicators, pigments (qv), and paint additives. 

Phthalocyanine Dyes. These days are synthesized as the metal complex on the textile fiber from, eg, phthalonittile and metal salts. A print paste typicaUy contains phthalonittile dissolved in a suitable solvent and nickel or copper salts. During a heat or steam fixation of 3—5 min, the dye is formed. The color range is restricted to blue and green shades and can be influenced to some extent by the choice of metal salt. A hot acid bath during afterscouting completes the process. 

The penetration of ions from the subphase into the shell of spread particles is a general phenomenon and can be used to modify and functionalize the particle surface. For example, metal ions, such as Ba and Fe, or cationic polyelectrolytes, such as the polycation of polyallylamine, can be adsorbed at anionic particles, while anionic water-soluble dyes, such as phthalocyanine tetrasulfonic acid and 1.4-diketo-3.6-diphenylpyrrolo[3.4-c]pyrrole-4, 4 -disulfonic acid (DPPS) [157], can be adsorbed at cationic particles. However, since only a monolayer of the dye is adsorbed, a deep coloration of the particles is not obtained unless a dye with very high absorption coefficient is used [156],... 

A detailed comparison [181] of three vinylsulphone dyes included a low-substantivity monoazo N-acetyl H acid derivative (Cl Reactive Red 35), a monoazo N-acetyl J acid type of higher substantivity (Cl Reactive Orange 82) and a phthalocyanine turquoise somewhat prone to aggregation (Cl Reactive Blue 21). Dyeings of these individual products were subjected to three wash-off procedures ... 

Water-soluble phthalocyanine dyes may contain only sulfonic acid groups but normally contain both sulfonic acid and sulfonamido groups. They are used as direct dyes for paper and as reactive dyes for cotton. Representative examples are Cl Direct Blue 199 (38) and Cl Reactive Blue 71 (39). These dyes are also used for the ink jet printing of textiles (see Section 9.12.6.2). 

There have also been attempts to obtain a black phthalocyanine dye for ink jet printing. Thus, a patent47 from Nippon Kayaku describes reacting the amino phthalocyanine (59) with acrylic or methacrylic acid to produce the black dyes (60). 

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