The influence of various substituent groups on the absorption spectra and pho tostability of some azo pyridone dyes has been examined in N,N-dimethyl-formamide. On exposure to a spectrum of ultraviolet radiation, photoreduction is mostly caused by radiation of 254 nm. The primary photochemical reaction with azo pyridone dyes involves hydrogen abstraction from the amide solvent. Two electron-withdrawing substituents in the diazo component of azo pyridone dye exert a bathochromic effect and increase the fading rate, while introduction of an alkylol group to the coupling component results in hypsochromic shifts and a decrease in the fading rate.
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References
1.
Ayyangar, N.R. , Lahoti, R.J., Lugade, A.G., and Otiv, S.R., Synthesis of Monoazo Disperse Dyes from 5Amino-3-methyl-1-(3',5-disubstituted)s-Triazinylpyrazoles and a Study of Their Visible Absorption and Dyeing Properties, J. Soc. Dyers Colour.102, 176-181 (1986).
2.
Bobbitt, J.M. , and Scola, D.A., Synthesis of Isoquinoline Alkaloids, II: The Synthesis and Reactions of 4-Methyl-3-Pyridinecarboxaldehyde and Other 4-Methyl-3-Substituted Pyridines, J. Org. Chem.25, 560-564 (1960).
3.
Bradiey, W., The Mechanism of the Coupling Process, J. Soc. Dyers Color.75, 289-291 (1959).
4.
Bridgeman, I. , and Petera, A.T., Photochemical Degradation of Aminoazobenzene Disperse Dyes in Ethanolic Solution, Part I: Effect of Concentration, Water, and Temperature, Textile Res. J.44, 639-645 (1974).
5.
Evans, N.A., Structural Functions, ch. 3 in "Photochemistry of Dyed and Pigmented Polymers," N. S. Allen and J. F. Mckeller, Eds., Applied Science, London, 1980, pp. 93-107.
6.
Giles, C.H., Johari, D.P., and Shah, C.D., SomeObservations on the Kinetics of Dye Fading, Textile Res. J.38, 1048-1056 (1968).
7.
Kuramoto, N. , and Kitao, T., The Photofading of 1-Arylazo-2-Naphthols in Solution, Part II: Contribution of Photoreduction to the Anomalous Photofading of 1-(p- and o-Nitrophenylazo)-2-Naphthols in Alcoholic Solvents, J. Soc. Dyers Colour.96, 529-534 (1980).
8.
Peters, A.T. , Substituent Effects on the Colour, Dyeing and Fastness Properties of Trisubstituted 4-N-β-Hydroxyethyl-N-β-Cyanoethylamino azobenzenes, J. Soc. Dyers Colour.101, 361-367 (1985).
9.
Peters, A.T. , Substituent Effects on the Colour, Dyeing and Fastness Properties of 4-Phenylazo-1-Naphthylamines and of 2-Acetylamino-5-Methoxy-4-N-β-Hydroxyethylamino azobenzene, J. Soc. Dyers Colour.104, 344-348 (1988).
10.
Peters, A.T. , and Chao, Y.C., Substituent Effects on the Colour, Dyeing and Fastness Properties of 4-Arylamino-8-Nitro-(and amino)-1,8-Dihydroxy-anthraquinone and 4-Arylamino-8-Nitro-(and amino)-1,5-Dihydroxyanthraquinone Disperse Dyes , J. Soc. Dyers Colour.104, 435-441 (1988).
11.
Takagi, K.M. , Kubo, Yuji, and Kitao, T., Quinone-Quinoneimine Tautomerism of 5,8-Bis(donor) substituted 1,4-Naphthoquinonoid Dyes, J. Soc. Dyers Colour.101, 140-143 (1985).
12.
Ukponmwan, D.O., Fastness Properties of Substituted Diamino-2-Methoxy-Anthraquinone Dyes, J. Textile Inst.58, 181-182 (1988).
