Azo dyes having 2,6-diaminopyridine derivatives as coupling components

A dye of the formula ##STR801## wherein:

• D is phenyl substituted by chlorine, bromine, trifluoromethyl, methyl, methoxy, nitro, cyano, methylsulfonyl, phenylsulfonyl, carbalkoxy of a total of 2 to 5 carbon atoms, carbo-.beta.-alkoxy-ethoxy, said alkoxy having 1 to 4 carbon atoms, or N,N-dialkyl- or N-monoalkyl-substituted sulfamoyl, each alkyl having 1 to 4 carbon atoms;
• phenylazophenyl;
• phenylazophenyl substituted by methyl, chlorine, bromine or nitro;
• benzthiazolyl;
• benzthiazolyl substituted by nitro, cyano, methylsulfonyl or ethylsulfonyl;
• benzisothiazolyl substituted by chlorine, bromine, cyano or nitro;
• thiazolyl substituted by cyano or nitro;
• thienyl substituted by methyl, cyano, nitro or carbalkoxy of a total of 2 to 5 carbon atoms;
• or thiadiazolyl substituted by phenyl, methyl, chlorine, bromine, methylmercapto, ethylmercapto or alkoxycarbonylethylmercapto, said alkoxy having 1 to 4 carbon atoms;
• R is alkyl of 1 to 3 carbon atoms;
• X is carbamoyl or cyano;
• R.sup.1 and
• R.sup.2 may be the same or different with the proviso that one of R.sup.1 and R.sup.2 is C.sub.6 H.sub.5 ;
• ##STR802## (CH.sub.2).sub.3 OCH.sub.2 CH.sub.2 OH;
• (CH.sub.2).sub.3 O(CH.sub.2).sub.6 OH;
• ##STR803## (CH.sub.2).sub.3 OC.sub.2 H.sub.4 OR.sup.7, (CH.sub.2).sub.3 (OC.sub.2 H.sub.4).sub.q OR.sup.8, (CH.sub.2).sub.3 OR.sup.9 ;
• ##STR804## C.sub.2 H.sub.4 OC.sub.6 H.sub.5, C.sub.2 H.sub.4 OC.sub.6 H.sub.4 CH.sub.3 ;
• ##STR805## and the other of R.sup.1 and R.sup.2 is hydrogen;
• alkyl of 1 to 8 carbon atoms;
• alkyl of 2 to 8 carbon atoms substituted by hydroxy, alkoxy of 1 to 8 carbon atoms, formyloxy, acetoxy, propionyloxy, carboxy, cyclohexoxy, benzyloxy, phenylethoxy, phenoxy or pyrrolidonyl;
• cyclohexyl;
• methylcyclohexyl;
• benzyl;
• phenylethyl;
• .beta.-phenyl-.beta.-hydroxyethyl;
• phenyl;
• tolyl;
• CH.sub.2 CH.sub.2 OCH.sub.2 CH.sub.2 OH;
• (CH.sub.2).sub.3 OC.sub.6 H.sub.5 --CH.sub.3 ;
• (CH.sub.2).sub.3 O(CH.sub.2).sub.4 OH;
• ##STR806## (CH.sub.2).sub.3 OC.sub.2 H.sub.4 OCH.sub.3 ;
• (CH.sub.2).sub.3 OC.sub.2 H.sub.4 OC.sub.6 H.sub.5 ;
• ##STR807## (CH.sub.2).sub.3 OCH.sub.2 CH.sub.2 OH;
• (CH.sub.2).sub.3 O(CH.sub.2).sub.6 OH;
• ##STR808## (CH.sub.2).sub.3 OC.sub.2 H.sub.4 OR.sup.7 ;
• (CH.sub.2).sub.3 (oc.sub.2 H.sub.4).sub.q OR.sup.8 ;
• ##STR809## C.sub.2 H.sub.4 OC.sub.6 H.sub.4 CH.sub.3 ;
• ##STR810## R.sup.3 is alkyl of one to three carbon atoms, hydroxymethyl or hydroxyethyl;
• R.sup.4 is hydrogen, alkyl of one to three carbon atoms, hydroxymethyl or hydroxyethyl;
• R.sup.5 is hydrogen or hydroxyl;
• R.sup.6 is hydrogen, alkyl of 1 to 4 carbon atoms, methoxy, ethoxy or chloro;
• one of R.sup.3 to R.sup.5 providing a hydroxy group;
• R.sup.7 is ethyl, propyl, butyl, cyclohexyl, benzyl, phenylethyl or methylphenyl;
• R.sup.8 is hydrogen, alkyl of one to four carbon atoms, cyclohexyl, phenyl, methylphenyl, benzyl or phenylethyl;
• R.sup.9 is cyclohexyl, phenyl, methylphenyl, benzyl or phenylethyl;
• m is 1 or 2;
• n is zero, 1 or 2;
• q is 2, 3 or 4;
• and
• p is 1, 2, 3 or 4.