Disperse Quinophthalone Dyes

Quinophthalone Dyes. Currently, 3 -hydroxyquinophthalone [7576-65-0] is employed extensively in a number of product lines used to dye synthetic fibers in greenish yellow hues with good lightfastness and generally sufficient sublimation-fastness. Suitable substitution in the phthalic acid residue or the quinoline nucleus may improve thermosetting fastness [29], An example is C.I. Disperse Yellow54, 47020 [7576-65-0] (10) ... 

Quinophthalones provide important dyes for the coloration of plastics (eg, Cl Solvent Yellow 33 (71), R = H [5662-03-3]) and for the coloration of polyester. For example. Cl Disperse Yellow 54 (71) R = OH, is the lea ding yellow dye for the transfer printing of polyester. 

The name of this structural class ( quinoline ) in the Colour Index is not ideal because quinoline derivatives feature in other related classes, such as the methine basic dyes with a quinolinium cationic group. The class is more precisely associated with quinophthalone (1.15), the characteristic chromogen derived by condensation of quinoline derivatives with phthalic anhydride. This small class of yellow compounds contributes to the disperse, acid, basic and solvent ranges of dyes. 

Quinophthalone (6.229) and its derivatives [86] also fall into the methine category, although they appear in the Colour Index under quinoline colouring matters. The parent compound was discovered in 1882 by Jacobsen, who condensed 2-methylquinoline (quinaldine) with phthalic anhydride. The product, quinoline yellow, is used as a solvent dye (Cl Solvent Yellow 33). The light fastness is improved by the presence of a hydroxy group in the quinoline ring system. Derivatives of this type provide greenish yellow disperse dyes for polyester. The moderate sublimation fastness of Cl Disperse Yellow 54 (6.230 R = H) is improved by the introduction of an adjacent bromine atom in Cl Disperse Yellow 64 (6.230 R = Br). 

E. Jacobson in 1882 fused phthalic anhydride with quinoline bases obtained from coal tar, which also contained quinaldine (136). He thus received quinophthalone (137). Quinophthalone derivatives bearing sulfonic or carboxylic acid functions represent suitable anionic dyes. Derivatives carrying basic side chains containing quarternary nitrogen, on the other hand, provide cationic dyes. The compounds are used especially as disperse dyes [1]. 

Quinophthalones, made by the condensation of phthalic anhydride with quinaldine derivatives, are one snch gronp, exemplified by Cl Disperse Yellow 54 (2.17a) and Yellow 64 (2.17b) nsed for polyester, especially for transfer printing and also as solvent dyes. 

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... 

Industrially applied disperse dyes are based on numerous chromophore systems. Approximately 60 % of all products are azo dyes, and ca. 25 % are anthraqui-none dyes, with the remainder distributed among quinophthalone, methine, naphthalimide, naphthoquinone, and nitro dyes [9],... 

Quinophthalone colorants have a long history as dyes, especially as disperse dyes, acid dyes and paper dyes l... 

Quinophthalone (3) and its derivatives are normally products with good solubility in organic media. Neutral compounds like 3-hydroxyquinophthalone and its bromi-nated derivatives are often used as disperse dyes for the coloration of polyester fibres and styrenics. Sulfonated derivatives represent suitable anionic dyes for the coloration of wool, silk, paper and food. Products carrying basic side chains with quaternary nitrogen atoms are used for coloring paper. ... 

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