Лако-красочные материалы — производство

2.3.1 Introduction Indigoid dyes represent one of the oldest known class of organic dyes. For 5000 years they have been used for dyeing textiles such as wool, linen, and cotton. For example, 6,6′-dibromoindigo is Tyrian Purple, the dye made famous by the Romans. Tyrian Purple was so expensive that only the very wealthy were able […]

These dyes contain one or more carbonyl groups linked by a quinonoid system. They tend to be relatively large molecules built up from smaller units, typically anthraquinones. Since they are applied to the substrate (usually cellulose) by a vatting process, the polycyclic aromatic carbonyl dyes are often referred to as anthraquinonoid vat dyes. In the […]

The benzodifuranone (BzDF) dyes are challenging anthraquinone dyes in the red shade area. The BzDF chromogen is one of the very few commercially useful novel chromogens to have been discovered in the twentieth century. As with many other discoveries [2] the BzDF chromogen was detected by accident. The pentacenequinone structure (3) assigned to the intensely […]

The principal advantages of anthraquinone dyes are brightness and good fastness properties, including lightfastness, but they are both expensive and tinctorially weak. However, they are still used to some extent, particularly for red and blue shades, because other dyes cannot provide the combination of properties offered by anthraquinone dyes, albeit at a price. Metallization would […]

Anthraquinone dyes are prepared by the stepwise introduction of substituents onto the preformed anthraquinone skeleton (1) or ring closure of appropriately substituted precursors. The degree of freedom for producing a variety of different structures is restricted, and the availability of only eight substitution centers imposes a further restriction on synthetic flexibility. Therefore, there is signifi­cantly […]

2.1.3 Introduction Once the second most important class of dyes, it also includes some of the oldest dyes; they have been found in the wrappings of mummies dating back over 4000 years. In contrast to the azo dyes, which have no natural counterparts, all the important natural red dyes were anthraquinones [1]. However, the importance […]

A long-term aim of dyes research has been to combine the brightness and fast­ness properties of anthraquinone dyes with the strength and economy of azo dyes. This aim is now being realized with heterocyclic azo dyes, which fall into two main groups: those derived from heterocyclic coupling components and those derived from heterocyclic diazo components. […]

These dyes are the backbone of most commercial dye ranges. Based entirely on benzene and naphthalene derivatives, they provide yellow, red, blue, green, and black colors for all the major substrates such as polyester, cellulose, nylon, poly­acrylonitrile, and leather. Typical structures are (79)-(84). C. I. Disperse Yellow 3 (79) is used to dye polyester; C. […]

2.1.1.1 Tautomerism In theory, azo dyes can undergo tautomerism: azo/hydrazone for hydroxyazo dyes; azo/imino for aminoazo dyes, and azonium/ammonium for protonated azo dyes. A more detailed account of azo dye trautomerism can be found elsewhere [2] . Azo/hydrazone tautomerism was discovered in 1884 [3]. The same orange dye was obtained by coupling benzenediazonium chloride with […]