GB429936A - Manufacture and application of new monoazo dyestuffs - Google Patents

Abstract

Monoazo dyes are made by coupling a diazotized 4-nitroaniline, in which the 2- and 6-positions are occupied by chlorine and/or bromine, with a p-coupling amine of the formula Ar--NRR1, where Ar is a benzene residue, R=H or alkyl, and R1=sulphatoethyl or sulphatopropyl. Alternatively, the sulphato group is introduced subsequent to coupling when R1=hydroxyethyl or hydroxypropyl. They dye or print acetate artificial silk, silk, tin-weighted silk, leather and wool in orange-brown to red-brown shades. In examples, dyes from the following components are described: 2 : 6-dichloro-, 2 : 6-dibromo- and 2-chloro-6-bromo-4-nitroaniline; N-methyl- or ethylsulphatoethylaniline, N - sulphatoethyl - m - amino - p - cresol methylether, N - methyl - or ethyl - N - g - sulphato - n - propylaniline. The dyestuff 2 - chloro - 6 - bromo - 4 - nitroaniline --> N - n - butyl - b - hydroxyethyl - m - toluidine is treated with 100 per cent sulphuric acid. Specifications 181,750 and 237,739, [both in Class 2 (iii)], are referred to. N - sulphatoalkyl compounds are made by treating the corresponding hydroxyalkyl compound with chlorsulphonic acid in tetrachloroethane or ethylene dichloride solution. N - n - butyl - b - hydroxyethyl - m - toluidine is obtained from N-b -hydroxyethyl-m-toluidine and n-butylchloride.