GB973238A - New chromium-complex and cobalt-complex compounds of monoazo-dyestuffs, their manufacture and use - Google Patents

Abstract

The invention comprises chromium complex or cobalt complex compounds of ortho-hydroxyortho1 - amino - monoazo - dyestuffs of the azo naphthalene series that contain a sulphonic acid alkyl amide group, the alkyl group of which is substituted by the acid radical of an inorganic oxy acid and that contain as residue of the coupling component that of a naphthylamine bound to the azo group vicinal to the amino group. The inorganic oxy acid referred to may be for example phosphoric or sulphuric acid. Particularly useful dyes are those of the kind defined having a sulphonic acid amide group of the formula <FORM:0973238/C4-C5/1> in which m and n each represent a whole number not greater than 3. The characteristic sulphonic amide group can be bound to an aromatic nucleus or in the residue of a coupling or diazo component or both. Especially valuable are the cobalt- and chromium-complexes of ortho-hydroxy-ortho1-amino-monoazo dyes that contain nitro groups and a sulphonamide group of the kind defined e.g. a sulphonic acid-N-a -sulphatoalkylamide group, especially 1 : 2-eobalt complexes of monoazo dyes of the formula <FORM:0973238/C4-C5/2> in which R represents a nitrobenzene residue bound to the azo bridge in ortho-position to the hydroxyl group, R1 represents a naphthylamine residue bound to the azo bridge in a position vicinal to the amino group, preferably a phenyl-amino group, one X represents a -SO2-NH-CH2CH2-OSO3H grouping, or 1 : 2-chromium or cobalt complexes of monoazo dyes of the formula <FORM:0973238/C4-C5/3> in which 2 represents an acylamino group or a hydrogen or a chlorine atom or a methyl or nitro group or an -SO2NH-CH2CH2-OSO3H grouping. Also mentioned are mixed complexes that contain a nitrophenol-azo-b -naphthylamine dye of the kind defined above and an ortho : ortho1-dihydroxy - dihydroxy - monoazo-dye of the keto methylene series. The metal complexes are obtained by treating the appropriate metal free dyes with chromium- or cobalt yielding agents in slightly acid to slightly alkaline media. The monoazo dyes used as starting materials can be obtained by esterification of appropriate dyes containing a sulphonic acid-N-hydroxyalkylamide group with e.g. phosphorus pentoxide, phosphorus oxychloride, concentrated sulphuric acid or chlorosulphonic acid. The esterification may be carried out in an inert organic solvent, e.g. dimethyl formamide. Additional substituents which may be present include halogen atoms, nitro, nitrile, acylamino, alkyl, alkoxy, sulphone, carboxylic acid, carboxylic ester, sulphonic and other sulphonamide groups. The dyes may also be made by esterifying appropriate complexes containing cobalt or chromium. The dyes are suitable for wool, silk, leather, polyamides and polyhydroxylated materials of fibrous structure, e.g. cellulose, especially cotton. Examples of the preparation of the dyes and their use in dyeing are furnished.