A dyestuff of the formula: ##STR1## in which A is thiazolyl, isothiazolyl, benzothiazolyl, benzisothiazolyl, thiadiazolyl, thienyl, or imidazolyl which is unsubstituted or substituted by one to three substituents selected from chlorine, bromine, methyl, phenyl, nitro, cyano, thiocyano, acetyl, carbalkoxy containing 2 to 5 carbon atoms and alkylsulfonyl containing 1 to 4 carbon atoms; PA1 X is hydrogen, chlorine, methyl, ethyl, methoxy, ethoxy, formylamino, acetylamino, propanoylamino, benzoylamino or cinnamoylamino; PA1 Y is hydrogen, methyl, ethyl, methoxy or ethoxy; PA1 R is hydrogen, alkyl containing 1 to 4 carbon atoms or the group of formula: ##STR2## said alkyl being unsubstituted or substituted by one hydroxy, alkoxy containing 1 to 4 carbon atoms, phenoxy, acetyloxy, cyano, alkylsulfonyl containing 1 to 4 carbon atoms, carbalkoxy containing 2 to 5 carbon atoms or alkoxycarbonyloxy containing 2 to 5 carbon atoms; PA1 N is equal to 1, 2 or 3; and PA1 Z is 2-cyanovinyl, 2-cyanoethyl or 2-chloro-2-cyanoethyl and which are useful as dispersion dyestuffs for dyeing and printing fibers of fibrous materials which are based on organic substances with high molecular weight, are hydrophobic and are wholly or partially synthetic.

The present invention relates to new azo compounds which are scarcely 
soluble in water and can be used as dispersion dyestuffs for dyeing and 
printing fibres or fibrous materials which are based on organic substances 
with high molecular weight, are hydrophobic and are wholly or partially 
synthetic. 
According to the present invention dyestuffs are provided of the general 
formula: 
##STR3## 
in which m is equal to 0 or 1, n is equal to 1, 2 or 3, preferably 2, A 
represents the residue of an aromatic or heterocyclic diazotisable amine 
devoid of any solubilising acid groups such as sulphonic or carboxylic 
groups, the benzene ring B is unsubstituted or substituted by one or two 
atoms of chlorine or bromine or methyl, ethyl, methoxy, ethoxy or 
acylamino groups, X represents a hydrogen or chlorine atom or a methyl, 
ethyl, methoxy, ethoxy or acylamino group, Y represents a hydrogen atom or 
a methyl, ethyl, methoxy or ethoxy group, R represents a hydrogen atom, a 
mono substituted or unsubstituted alkyl group, or a group of the formula: 
##STR4## 
and Z represents a 2-cyano-vinyl residue, a 2-cyano-ethyl residue or a 
2-chloro-2-cyano-ethyl residue fixed in the ortho, meta or para postion. 
Examples of residue A are phenyl, naphthyl, thiazolyl, benzothiazolyl, 
benzisothiazolyl, thienyl, thiadiazolyl and imidazolyl. These residues may 
have from one to three substituents such as, for example, chlorine or 
bromine atoms or the nitro, cyano, thiocyano, acyl, carbalkoxy containing 
two to five carbon atoms or alkylsulphonyl groups containing 1 to 4 carbon 
atoms. 
The alkyl group, which may be represented by R or which is part of the 
alkylsulphonyl groups possibly present on the A residue preferably 
contains 1 to 4 carbon atoms. The carbalkoxy group possibly present on the 
A residue preferably contains 2 to 5 carbon atoms. 
The acyl residue of the acylamino groups which are possibly present on the 
B ring or may be represented by X, may be that of an aliphatic acid with a 
low molecular weight, such as for example formyl, acetyl or propanoyl, or 
that of an aromatic acid, for example benzoyl, or of an araliphatic acid, 
for example, cinnamoyl. 
The acetyl group may be mentioned more particularly as an acyl residue 
which is possibly present on the A residue. 
The hydroxy, alkoxy containing one to four carbon atoms, phenoxy, acyloxy, 
especially acetyloxy, nitrile, alkylsulphonyl, containing one to four 
carbon atoms, carbalkoxy, containing two to five carbon atoms, 
alkoxycarbonyloxy groups containing two to five carbon atoms may be 
mentioned as possible substituents of the alkyl group which may be 
represented by R. 
The dyestuffs of formula (I) may be prepared for example by coupling the 
diazo derivative of an amine of the formula: 
##STR5## 
with an ester of the formula: 
##STR6## 
or with an alcohol of the formula: 
##STR7## 
and, in this latter case, subsequently esterifying the dyestuff thus 
obtained of the formula: 
##STR8## 
for example by means of an acid chloride of the formula: 
##STR9## 
In formulae (III) to (VII), m, n, A, B, R, X, Y and Z have the same 
meanings as given above. 
The amine of formula (III) may be diazotised for example in a known manner 
by means of sodium nitrite in a hydrochloric or sulphuric medium or by 
means of nitrosyl sulphuric acid mixed with sulphuric acid or possibly a 
carboxylic acid such as acetic or propionic acid, at a temperature of 
approximately 0.degree. C. 
The coupling with the ester (IV) or with the alcohol (V) may also be 
effected for example in a known manner in a neutral or acid aqueous medium 
at a temperature of from 0.degree. C. to 5.degree. C. 
The dyestuff of formula (VI) is preferably esterified by means of the acid 
chloride of formula (VII) in an inert organic solvent, in the presence of 
a proton acceptor such as for example pyridine, piperidine or a trialkyl 
amine such as triethyl amine. Examples of inert organic solvents are 
halogenated hydrocarbons such as methylene chloride, trichlorethylene or 
chlorobenzene, ketones such as acetone or methyl ethyl ketone and ethers 
such as diethyl ether, dioxan and methoxy benzene. 
The esters of formula (IV) are new products and, as such, form part of the 
invention. They may be prepared for example, by esterifying the alcohol of 
formula (V) by means of an acid chloride of formula (VII) under the same 
conditions as those given above for the esterification of the dyestuffs of 
formula (VI). 
The acid chlorides of formula (VII) may be prepared for example by reacting 
thionyl chloride with the corresponding acids of the formula: 
##STR10## 
wherein Z has the same meaning as that given above. 
The acids of formula (VIII), in which Z represents the 2-chloro 2-cyano 
ethyl residue (--CH.sub.2 --CHCl--CN), may be prepared, for example, by 
the Meerwein reaction between acrylonitrile and the diazonium chloride of 
2-,3- or 4-amino benzoic acid. By means of a dehydro halogenation process 
with an alkaline agent, the acids of formula (VIII) are then obtained, in 
which Z represents the 2-cyano vinyl residue. The acids of formula (VIII), 
in which Z represents the 2-cyano ethyl residue, may be obtained for 
example by reducing (2-chloro-2-cyano ethyl)benzoic acids. 
The new dyestuffs of formula (I), and more particularly those in which m is 
equal to zero, Y represents a hydrogen atom, X represents a hydrogen or 
chlorine atom or a methyl or acetylamino group, R represents an ethyl or 
.beta.-cyanoethyl group and n is equal to 2, are remarkable disperse 
dyestuffs which are highly suitable for dyeing and printing fibres and 
fabrics based on aromatic polyesters or cellulose triacetate. Some of 
these dyestuffs are also suitable for dyeing cellulose diacetate and 
polyamides. Before they are used, it is recommended that they be converted 
into tinctorial preparations, i.e., that they be pre-dispersed with 
dispersing agents such as soap, the residual lyes of sulphite cellulose, 
the products resulting from condensing naphthalene-sulphonic acids with 
formaldehyde, in particular the dinaphthyl-methane-disulphonate, the 
sulphonated esters of succinic acid, the products obtained by condensing 
cresols with formaldehyde and naphtholsulphonic acids. 
Polyester fibres may be dyed in the presence of carriers at temperatures 
ranging from 80.degree. C. to 125.degree. C. or without a carrier under 
pressure between 100.degree. C. and 140.degree. C. They may also be 
foularded or printed with aqueous dispersions of the new dyestuffs which 
are then fixed at 140.degree. C. to 220.degree. C. 
The dyestuffs of formula (I) have excellent affinity for these fibres which 
they dye in shades which are very fast, particularly to sublimation and 
light. 
Compared with the close known dyestuffs of formula (I), in which the 
residue 
##STR11## 
is replaced by an acetyl, benzoyl, p-chlorobenzoyl or cinnamoyl residue, 
the new dyestuffs of the invention generally have superior fastness to 
sublimation whilst retaining an excellent tinctorial affinity. 
The invention is illustrated by the following Examples, in which the parts 
indicated are parts by weight unless otherwise mentioned.