GB421592A - Improvements in or relating to the manufacture of new dyestuffs of the triarylmethane series - Google Patents

Abstract

Triarylmethane dyes are prepared by introducing the group Alk--SO3H, wherein "Alk" stands for an alkyl group of at least three carbon atoms, into the primary or secondary amino group of a triarylmethane compound by condensing a halogen-alkylsulphonic acid containing an alkyl group of at least 3 carbon atoms with a dyestuff of the triarylmethane series containing at least one primary or secondary amino group. Or an aromatic aminosulphonic acid of the formula <FORM:0421592/IV/1> wherein R stands for hydrogen, alkyl, aralkyl or aryl, and "Alk" stands for an alkyl group of at least three carbon atoms, is condensed with components customary for the manufacture of triarylmethane dyes, and the resulting compounds oxidized. In an example, butylphenylaminopropane-sulphonic acid (prepared by introducing b -hydroxypropylbutylaniline-(propyleneoxide on butylaniline)- into concentrated sulphuric acid, neutralizing the resulting ester and boiling this with sodium sulphite) is condensed with o-chlorbenzaldehyde and the product oxidized to a green dye for animal fibres. Also ethylphenylaminobutane sulphonic acid (prepared by condensing ethylaniline with butyleneoxide under pressure, converting the resulting oxybutylethylaniline into the sulphuric ester by means of mono-hydrate, neutralizing and boiling with aqueous sodium sulphite) is condensed with o-chlorbenzaldehyde in presence of hydrochloric acid, and the leuco compound oxidized to the dye. The Specification as open to inspection under Sect. 91 relates to the production of triarylmethane dyes by the introduction of the specified group alk--SO3H into triarylmethane compounds by methods known per se, but this subject-matter does not appear in the Specification as accepted.