Лако-красочные материалы — производство

Virtually every conceivable chromophore has been used in the synthesis of reac­tive dyes, including monoazo and disazo species, metal complexes of azo dyes, formazan dyes, anthraquinones, triphenodioxazines, and phthalocyanines. The product lines offered by the major dye producers in most cases feature compar­able chromophores, differing primarily in the nature of the reactive systems and the particular substitution patterns adopted.

3.1.1.1 Azo Dyes [12], [37]

Most reactive dyes fall in the category of azo dyes. Virtually every hue in the dye spectrum can be achieved by appropriate structural modifications (mono — and disazo dyes, combinations involving either single or multiple aromatic and het­erocyclic ring systems).

Monoazo dyes with heterocyclic coupling components, such as pyrazolone or pyridone, are yellow to greenish yellow. Other suitable coupling components include aniline and naphthylamine derivatives. Substituted anilines or amino- naphthalenesulfonic acids are employed as diazo components. Examples are C. I. Reactive Yellow4, C. I. Reactive Yellow 17 (see Section 3.1.5).

A particularly important class of coupling components are the aminohydroxy- naphthalenesulfonic acids. Appropriate variation of the disazo component per­mits the development of shades ranging from orange to black. Orange and scarlet are achieved with I-acid (6-amino-1-hydroxy-naphthalene-3-sulfonic acid) and y-acid (7-amino-1-hydroxynaphthalene-3-sulfonic acid), whereas H-acid (8-amino- 1-hydroxynaphthalene-3,6-disulfonic acid) and K-acid (8-amino-1-hydroxy- naphthalene-3,5-disulfonic acid) derivatives are useful for red to bluish-red hues. Extremely lightfast red shades are also accessible with disazo dyes (“brown dyes”). For chemical structures see Section 3.1.5).

When H-acid is used as a double coupling component, as in 13, in which reac­tive groups are present in both diazo functions, the resulting dye color ranges from blue to black.