INSOLUBLE MONO- AND DISAZO DYESTUFFS CONTAINING A 1,3 - BENZOXAZOLIN - 2 - ONE GROUP

The invention provides water-insoluble dyes of general formula in which K is the radical of a coupling component of the aromatic or 1-alkyl or 1-aryl-pyrazole series and K1 is the radical of a coupling component of the aromatic or heterocyclic series, m is 0 when K is a 1-alkyl or 1-aryl pyrazole compound and is 0 or 1 when K is an aromatic radical. The dyes are free from sulphonic or carboxylic acid groups but may contain other non-ionic substituents. The dyes are prepared by diazotizing an amine of formula i.e., 5 - amino - benzoxazolin - (1,3)-one - (2) and coupling with a 1-aryl or 1-alkyl-pyrazole or an aromatic coupling component, the latter when having an amino group may then be diazotized and coupled with an aromatic or heterocyclic compound. Red-yellow shades are obtained on cellulose ester and polyamide materials.ALSO:Dyes of general formula in which K is a coupling component of the aromatic or 1-alkyl or 1-aryl-pyrazole series and K1 is a coupling component of the aromatic or hetrocyclic series, or is O when K is a radical of the 1-alkyl or 1-aryl-pyrazole series and for 0 or 1 when K is an aromatic radical, the dyes being free from sulphonic and carboxylic acid groups but may possess other non-ionic substituents, are used for dyeing cellulose ester, polyamide and polyester materials. In Example 1 polyester fibres are dyed at 40-60 DEG C rising to boiling at pH about 4.5 in presence of 2-hydroxy-diphenyl.