Application in the Chemistry of Dyes

In recent years advances in the chemistry of leuco dyes have taken place particularly in the areas of structural identification by means of H- and 13C-NMR and selective syntheses of aminoquinones, etc. New applications of leuco quinones such as in electro-optical devices and information recording media have enhanced their importance. In these applications, the chemistry of leuco quinones is interesting mainly due to switching from a colored to a colorless system by a redox process. 

Volume 9 is concerned with actual and potential applications of metal coordination complexes. Major developments since the 1980s in the uses of coordination compounds have occurred in catalysis and medicine. There have been important developments of coordination chemistry in the technology of dyes and optical materials, for solar energy harvesting, for hydrometallurgical extraction, and in providing MOCVD precursors for new electronic materials. As mentioned above, the last volume in the series contains the indexes. 

Porous materials with large internal surface areas have attracted considerable attention in surface chemistry, catalysis and chromatography. In principle, a vast choice of porous materials is available. While some inspiration can indeed be drawn from chemical applications, the choices for useful photovoltaic substrate materials are considerably narrowed by the requirement to have thin-film constituency, transparency and electronic conductivity. Indeed, these requirements are so stringent that only a few substrate types and materials have so far been found suitable. Sintered nanocrystalline oxide films are one major class of these. Much development work on these materials has been reported in the context of dye-sensitised cells, and this is... 

This series in heterocychc chemistry is being introduced to collectively make available critically and comprehensively reviewed hterature scattered in various journals as papers and review articles. All sorts of heterocyclic compounds originating from synthesis, natural products, marine products, insects, etc. will be covered. Several heterocyclic compounds play a significant role in maintaining life. Blood constituents hemoglobin and purines, as well as pyrimidines, are constituents of nucleic acid (DNA and RNA). Several amino acids, carbohydrates, vitamins, alkaloids, antibiotics, etc. are also heterocyclic compounds that are essential for life. Heterocyclic compounds are widely used in clinical practice as drugs, but all applications of heterocyclic medicines can not be discussed in detail. In addition to such applications, heterocyclic compounds also find several applications in the plastics industry, in photography as sensitizers and developers, and the in dye industry as dyes, etc. 

Another noted and prolific Japanese author in the field of functional dyes, Masaru Matsuoka of the Laboratory of Materials Science, Kyoto Women s University, has written the second chapter, dealing with leuco-quinone dyes. These are the traditional redox leuco systems employed for so many years in the vat dyeing industry, and this chapter is an invaluable review of the chemistry of these systems, drawing on recent mechanistic and structural investigations. Applications considered include not only textile dyeing, but also other more specialized areas, such as hair dyeing, color formers, and photoimaging materials. 

The chemistry of these phthalides has much in common with that of the compounds reviewed in the next chapter, i.e., the feMco-triarylmethanes, and in fact, the parent dyes of the two classes share the same basic chromophoric system. However, the latter are true redox systems, rather than pH indicators, and consequently have a different range of technical applications. The situation is complicated further in that the triarylmethane cationic dyes can also bleach at high pH, giving a hydroxide addition... 

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