摘要 |
<p>The novel, water-sol. azo dyes free from carboxylic acid and sulphonic acid gps., are of formula (I): (where R is H, halogen, CN, NO2, OH, NH2 or an organic radical; R' is H, opt. substd. hydrocarbon or heterocyclic radical, or opt. substd. NH2; R2 is opt. substd. >=3C alkyl, or opt. substd. aryl, or aralkyl; K + is a cationic radical; X - is an anion; and A may carry other substituents or may be condensed with a benzene ring). (I) are also used for acid-modified poly-amides and polyesters. They do not show instability in aq. solns. and loss in colour due to decomposition, on dyeing. (I) may be used for transfer printing processes under moist conditions. In an example, n-hexyl anthranilate is diazotised and coupled with 2-keto-3-(pyridinium chloride)-4-methyl-6-hydroxy-1:2-dihydropyridine.</p> |