Phthalocyanine dyes

The water-soluble reactive phthalocyanine dyes (see Section 2.8) yield brilliant turquoise and green shades not available from any other dye category. The most important reactive phthalocyanine dyes contain copper or nickel as their central atom they are substituted with sulfonic acid groups and also with reactive groups joined via sulfonamide bridges. An example is C.I. Reactive Blue 15, 74459 [12225-39-7] (23)  

The synthesis of selected reactive dyes is illustrated by the following examples taken from the patent literature. 

Azo Dyes. The dye obtained by coupling diazotized 4-(2-sulfooxyethylsulfonyl)ani-line with l-amino-8-naphthol-3,6-disulfonic acid at pH 1 - 2 is coupled at pH 6 - 7 with a diazonium compound synthesized from the condensation product derived from l,3-diaminobenzene-6-sulfonic acid and 2,4,6-trifluoro-5-chloropyrimidine. The crude material is salted out of the solution and isolated. This product (24) gives a blue solution in water and dyes cotton in a marine blue to black color  

Metal-Complex (Formazan) Dyes. The hydrazone from 2-carboxyphenylhydra-zine-4-sulfonic acid and benzaldehyde is suspended in water and then dissolved by adding aqueous sodium hydroxide to obtain pH 6.5 -7.0. This solution is added to the aqueous diazonium salt solution obtained from a typical aqueous diazotiza-tion of 4-(2-sulfooxyethylsulfonyl)-2-aminophenyl-6-sulfonic acid. The mixture is then dripped into an aqueous solution of copper sulfate, while the pH is maintained with soda at 5.5 - 6.5. After complete coupling the pH is adjusted to 1 with concentrated hydrochloric acid. The strongly acidic solution is then neutralized with alkali to pH 5.5. The copper - formazan complex is salted out along with sodium chloride, filtered, washed with dilute aqueous sodium chloride solution, and dried. A dark powder results which gives a dark blue solution in water. It consists of an electrolyte-containing powdered sodium salt of the acid 25  

This compound is a very effective dye that renders cotton and regenerated cellulose fibers a clear blue shade on prolonged treatment in the presence of an acid-binding agent. The resulting color prove to be veiy light- and waterfast. 

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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. 

Dyes may be classified according to chemical stmcture or by thek usage or appHcation method. The former approach is adopted by practicing dye chemists who use terms such as a2o dyes, anthraquinone dyes, and phthalocyanine dyes. The latter approach is used predominantiy by the dye user, the dye technologist, who speaks of reactive dyes for cotton and disperse dyes for polyester. Very often, both terminologies are used, for example, an a2o disperse dye for polyester and a phthalocyanine reactive dye for cotton. 

Like phthalocyanine dyes, triphendioxa2ine dyes are large molecules, and therefore their use is restricted to coloring the more open-stmctured substrates such as paper and cotton. 

Of all the metal complexes evaluated, copper phthalocyanines give the best combination of color and properties and consequentiy the majority of phthalocyanine dyes are based on copper phthalocyanine Cl Direct Blue 86 [1330-38-7] (Cl 74180) (68) is a typical dye. 

Phthalocyanine Dyes. The phthalocyanine molecule is much too big to be used on hydrophobic fibers and therefore is only used in its sulfonated form as the basis for direct and reactive dyes (see Phthalocyanine compounds). Its forces of attraction are different from a small linear yeUow a2o dye with which it is used to form bright greens. CompatibiHty between the two is likely to be a problem in practice and to overcome this, green dyestuffs containing a phthalocyanine dye linked via a saturated chromophore blocker (—x—) have been made, eg,... 

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. 

In view of the immense commercial importance of phthalocyanines as pigments, it is perhaps surprising that only a few are of importance as textile dyes. This is primarily due to the size of the molecules they are too large to allow penetration into many fibres, especially the synthetic fibres polyester and polyacrylonitrile. An example of a phthalocyanine dye which may be used to dye cellulosic substrates such as cotton and paper is C. I. Direct Blue 86 (96), a disulfonated copper phthalocyanine. In addition, a few blue reactive dyes for cotton incorporate the copper phthalocyanine system as the chromophoric unit (Chapter 8). 

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). 

The blue aluminum phthalocyanine dye, Tinolux BBS (74), marketed by Ciba, is a commercial SOG.77,78 Zinc phthalocyanines, such as (75), which absorb in the near infrared at 725 nm, are also very good SOGs.73... 

There are no clear advantages in terms of functional performance between the two classes of dyes, except that phthalocyanines are generally more light stable but tend to be more expensive to synthesize and modify. Phthalocyanine dyes are not suitable for DVD-R media, since the main chromophore cannot readily be modified to produce a sufficiently large hypsochromic shift. Other dyes potentially suitable for DVD-R include metal azo complexes, quinophthalones, and diphenyl-methanes. The cyanine dyes are particularly useful as they can be readily modified to tailor the optical absorbance requirements for all current optical disk recording applications.199... 

A number of these dyes were applied, mixed with a polymer for the control of the aggregation state, to CD-R and DVD-R recording systems. The aggregation state in the recording layer was controlled by choosing the set of axial substituents (Scheme 8 R1, R2, and R3). The interaction between the phthalocyanine dyes and the polymers was dependent on the length of the axial substituents or, more carbon atoms in the alkyl group were found to be necessary for the axial substituents to mix with the polymers.218... 

Shen, S. Liu, K. Huijun, X. Gu, D. Tang, F. Chen, Q. Spectroscopic properties of phthalocyanine dyes for optical recording medium. Proc. SPIE Vol. 2931, 73-77. Fourth International Symposium on Optical Storage (ISOS 96), Gan, F.X., Ed. 

The relative and absolute configurations of diepoxydicarbazoles involving the 2,6-dioxa-4,8-diazaadamantane system were determined in the course of a study on indole and indole alkaloids.242 Water-soluble azo, anthraquinone, and phthalocyanine dyes which are substituted by a 4-chloro-s-triazin-2-ylamino group can be quaternized with a l-aza-3-methyl-4,6,10-trioxa-adamantane unit in aqueous medium at 40 50"C.243 Dyes mixed with... 

Abbreviation for parts per hundred of rubber. Phthalocyanine Dyes... 

They were introduced in the late 1940s for the textile printing of cellulosic fabrics under the trade names Alcian (ICI) and Phthalogen (BAY). Both types resulted in the insolubilisation of copper phthalocyanine or related pigments within the fibre, although the respective application techniques differed considerably. Reactive phthalocyanine dyes in the 1960s superseded these early approaches to the attainment of fast bright blues and turquoises on cellulosic fabrics [63]. 

An appropriate ion-specific electrode was found to provide a convenient, precise and relatively inexpensive method for potentiometry of copper(II) ion in copper-complex azo or formazan dyes. Copper(II) ion in copper phthalocyanine dyes can be quantified after anion exchange. Twelve commercial premetallised dyes evaluated using this technique contained copper(II) ion concentrations in the range 0.007 to 0.2%. Thus many copper-complex direct or reactive dyes are likely to contribute low but possibly significant amounts of ionic copper to textile dyeing effluents [52]. 

Aerobic biodegradation processes often show unsatisfying results because a number of azo dyes are resistant to aerobic microbiological attack. The main process for removal of dyes in the aerobic part of a CWWT is based on an adsorption of the dyes on the biomass. Further problems in the destruction of chromophores result during the treatment of phthalocyanine dyes, anthraquinoid dyes, and vat and sulfur dyes, which contain rather persistent chromophores. 

The second dye system is based on an almost clear yellow-green phthalocyanine dye. The estimated lifetime of a disc based on the phthalocyanine dye is 100 years. The third dye system is based on azo dyes. The azo dye used in the process has a deep blue color partially caused by its unique silver alloy reflective layer. Again, a projected lifetime of 100 years is cited. 

Alloway DM, Armstrong NR (2009) Organic heterojunctions of layered perylene and phthalocyanine dyes characterization with UV-photoelectron spectroscopy and luminescence quenching. Appl Phys A 95 209... 

Unfortunately there are no experimental results which could be compared with these theoretical curves. All experiments reported in the literature are either made with cyanine dyes showing some excited state absorption or with phthalocyanine dyes which have an extremely high intersystem crossing rate so that triplet populations cannot be neglected. 

Another class of ballasted dye releasers is represented by the sulfonylhydrazone (88). These compounds interact with oxidized p-phenylenediamines to give sulfinate-solubilized dyes (89). Y can be the residue of an azo, anthraquinone or phthalocyanine dye (73BRP1321046, 75BRP1407362). 

Ink -dewatering of [DEWATERING] (Vol 8) -fluorescent pigments in [LUMINESCENTMATERIALS - FLUORESCENT PIGMENTS (DAYLIGHT)] (Vol 15) -as paper contaminant [RECYCLING - PAPER] (Vol 21) -phthalocyanine dyes [PHTHALOCYANINE COMPOUNDS] (Vol 18)... 

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