Hoechst Aktiengesellschaft

Heinrich Hamal

Rudolf Kuhne

Erwin Dietz

Frank Prokschy

A process for the preparation of 2-(arylamino)-3-carboxy-9(10H)-acridones of the formula A ##STR1## in which R and R' represent hydrogen, fluorine, chlorine or bromine atoms, alkyl(C.sub.1 -C.sub.4)-, oxalkyl(C.sub.1 -C.sub.4)- or carbonamide groups and x and y denote integers from 1 to 4, by cyclizing 2,5-diarylaminoterephthalic acids of the formula D ##STR2## in which R, R', x and y have the meanings mentioned previously, in a 5- to 15-fold amount by weight of polyphosphoric acid (P.sub.4 O.sub.10 content 80 to about 85%) or of an acidic polyphosphate (P.sub.4 O.sub.10 contents 75 to about 85%) as a water-abstracting agent at about 60.degree. C. to about 100.degree. C.

Process for the preparation of 2-(arylamino)-3-carboxy-9(10H)-acridones

When a diamine of the formula ##STR1## in which n is 1 to 4, is bis-diazotized and the resulting bis-diazo compound is coupled with 2 moles of one or more coupling components of the formula ##STR2## in which R.sup.1 is hydrogen, chlorine, bromine, methyl or methoxy and R.sup.2 is hydrogen or, if R.sup.1 is hydrogen, also methyl or ethyl, disazo compounds are obtained which are colorants. Due to their high fastness to light and to migration and their heat stability and dispersibility, these compounds are useful for pigmenting high molecular weight materials, especially polyolefins.

Diazo compounds, a process for their preparation and their use as

Symmetrical and asymmetrical disazo compounds of the formula: ##STR1## wherein: the R.sup.1 's are identical or different and are hydrogen, chlorine, bromine, methyl or methoxy;

Symmetrical and asymmetrical disazo compounds having a bis-aryloxy

Compounds of the formula ##STR1## wherein one of the pairs of substituents X and X' on the one hand and Y and Y' on the other hand stands for nitro and the other for amino and wherein n is 1 to 4, are diazo components, especially for disazo pigments of high tinctorial strength and purity of shade.

Nitroamines, processes for their manufacture and their use as diazo

Symmetrical and asymmetrical disazo compounds of the formula ##STR1## wherein K is the radical of an enolized or enolizable coupling component,

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Heinrich Hamal