US1877743A - Azo-dyestuff and process of making same - Google Patents

Description

Patented Sept. 13, 1932 UNITED STATES PATENT OFFICE FRITZ STRAUB AND WALTER ANDERAU, OF BASED, SWITZERLAND, ASSIGNORS TO FIRM OE SOCIETY OF CHEMICAL INDUSTRY IN BASLE, OF BASED, SWITZERLAND AZO-DYESTUFF AND PROCESS OF MAKING SAME e No Drawing. Application filed June 10, 1930, Serial No. 460,283, and in Switzerland June 12, 1929.

This invention relates to thefmanufacture of new azo-dyestuil's. It-comprises the proo ess of making these dyestuffs, the new dyestuffs themselves, as well as the materlal dyed therewith.

According to this invention valuable azodyestuffs containing an azine nucleus are obtained by coupling at least one molecular proportion of a diazo-compound of the general formula wherein It stands for an aryl residue which may contain substitu.ents,w1th an azine WlllCll is obtained by treating with acids the azodyestuffs of the general formula in which R and B stands for aryl residues which may contain substituents, one y is an OH-group and the other 2 a hydrogen atom, one a an SO H-group and the other 2 a hydrogen atom, the SO H-group and the OH-group being in meta-position to each other.

If the diam-compounds which are to come into use derive from compounds of the general formula in which :0 stands for such a group in orthoposition to the -N=N-OH residue which, in combinationwith the azo-ohromophore of the dyestufl", imparts to the latter the capability of binding metals adapted to, form lakes, and in which R stands for an aryl residue, which may contain further substituents, the azo-dyestufis which are obtained after the coupling with the said azines may yet be treated with agents yielding metals capable of forming lakes.

Azines of the stated kind may be made from an N-substituted 2-amino-5-hydroxynaphthalene-'T-s-ulfonic acid or from an N- substituted 2-amino-8-hydroxynaphthalene- I 6-sulfonic acid, by coupling a diazo-compound in an acidmedium and treatin g with an acid the ortho-amino-azo-dyestuif thus obtained. Among other compounds the following N-substitution products of 2-amino-5- hydroxynaphthalene-7-sulfonic acid or 2- amino 8 hydroxynaphthalene 6 sulfonic The azines can be coupled with any diazocompound. Azines which can be coupled twice, may be treated once or twice with the same or with different diam-compounds.

The dyestuiis may be produced on the fibre, in which case it is advantageous to pad the fibre with the azine in the form of its leuco-compound and, after oxidation, to develop the dyeing withthe diazo-compound. l

Dyestuiis which show mordant properties can be treated in substance, in the course of their manufacture, in the dye-bath or on the fibre with an agent yielding metal, whereby conversion into the metal compound may occur whether in acid, neutral or alkaline medium, with or without a suitable addition,

and at ordinary pressure or under increased 5 pressure. The metals which are suitable for the present processare those which can form complexes, for instance those Which have the atomic Weight 27 to 66, such as, for example, chromium, copper, iron, cobalt or nickel.

It is also possible to obtain dyestuffs containing several metals. The products of the invention may be used for dyeing wool, silk or cotton, viscose and varnishes.

The followingv example illustrates the manufacture of such azines which are being used for the production of dyestuffs in accordance with the present. invention, the parts being by Weight vTo the diazo-compound from 209 parts of sulfanilic acid there are added the freshly precipitated suspension, feebly acid with mineral acid, of 862 parts of 2-ortho-carboxy-phenylamine-5-hydroXynaphthalene-7- sulfonic acid and the mixture is stirred at r the ordinary temperature until the .diazocompound has pling is complete the whole is warmed on the water-bath until a sample of .the dyestufl dissolved to a, pure. yellow solution in dilute acetic acid. By adding 20-50parts of hydrochloric acid the formation of azine may be accelerated. When conversion is complete the liquid is nade alkaline with sodium disappeared. When coucarbonate and the sodium salt of the 2-sulfo- 4-hydroxy-a-fl-naphtho-8-carboxy-phenazine of the probable formula i soan to a green-blue'solution. Alkaline reducing agents convert the product into the dihydroazine which is soluble to a yellow solution. The azine is capable of coupling with diazocompounds.

The reaction may be extended to the various homologues of the 2-arylamino-hydroxynaphthalene-sulfonic acid series.

The following table shows the properties 9 of some of the azines which are used for the production of dyestuffs according to the present invention r Reactions Nomenclature (Richter) and Parent material consmunm cnaooon HOl 10 Soda Vat 5 E3 1 10 per cent per cent 10 per cent cent, NaOH Hated (1) 2 'sulfo 4 hydroxy a B 2-para' -l1ydroxy meta Orange Blue-red Red Blue-red Yellowish- Violetnaphtho- 10- hydroxy 9 (11) carboxyphenylamino-5- V 1 orange. black carboxyphenazine. naphthol' 7 sulfonic acid.

v N OH OH- O O OH N (2) 2 sulfo 4 hydroxy a B 2 pafa carboxyphenyl- Orange Red Red Red- Yellow Violet naphtha l0 carboxyphenazlne ammo 5 -rnaphthol 7- sulfonic acid OOOH Reactions Nomenclature (Richter) and Parent material c n titutl 11 5 omooon H0110 Soda fggg Vat 5 8; 5 10 per cent per cent 10 per cent cent NaOH trated n} (3) 2 sulfo 4 hydroxy a fl 2 para ethoxyphenyl Orange Red Red Orange Yellow Violetnaphtho 10 ethoxy phenaamino 5 naphthol 7 brown. zine snlfonic acid.

SO H

. N 011 v oaaao I U r m (4) 2 11 4 hydroxy a 2 ortho methoxyphe- Orange Bed pre- Orange Orange Yellow Green-blue naphtho 8 Inethoxyphenazine y q 5 D clpltate 7 sulfomc acid SIQaH /2\ 2e 1 3 r J 11 9 8 I 6 a 95 K N/ 00113 (5) 2-sulfo l hydtoxy a ,3 2 ortho pai a -dimeth- Brownish- B1ue-red Reddish- Red Yellow Blackishnaphtho 8:10 dimethylphena y p e y 5 aee o ange blue-viozine naphthol 7 sulfonic let S0311 a d 39 i (j OH 7 N CH3 as G:

(5) 2 sulfo 4 hydroxy a 2 Ineta ehlorophenyl- Orange Brownish- Red Red Yellow Violet naphtho-Q (11) -chlotophenazine 7 red 7 sulfomc acid The following examples illustrate the mansodinm carbonate in 450 parts of water. uiaoture and application of dyestuffs in ac- There are then added 16 parts of sodium be cordance With the invention, the parts being carbonate and the temperature is reduced to by Weight 56 C. by means ofice,v.rl1erenpon the diazo- Example 1 compound from 12.3 parts of ortho-anisidine -33 1 1 j v htho 1S IDlZIOClHCOQl. After a short time the cougg g fl g z ggz gfi Imp pling 1s finished and the dyestulif of the m: o formula du N I l N 30 I\N w soaz- H300 HOS a OH 7 are dissolved with aid of-5.5 parts of calcined may be filtered and dried. It is a dark pow J E azample 2 30 parts of 2-sulfo-4-hydroXyx-;8-naphth0- phenazine are dissolved in .330 parts of water with aid of 25 parts of calcined sodium carbonate, and the solution is coupled at 810 G. with the diazo-compound from 22 parts of 4 nitro 2- amino l-phenol-G-sulfonic acid. After some hours the coupling is complete and the dyestuff of the formula OH Hois- HOaS may be separated by salting out. It is a brown powder soluble in dilute acetic acid to an orange solution. In dilute sodium carbonate solution it dissolves to blackish-brownviolet (dichroitic) solution and in concentrated sulfuric acid to a green solution. It dyes wool in an acid bath blackish-green tints, which become fast blaekish-violet'by aftertreatment with a copper salt and a dark green on treatment with a chromium salt. Cotton is dyed in a bath alkaline with sodium carbonate grey tints, which yield a fast violet on In the presafter-treatment with copper. ence of chromium salts cottonls dyed olivegreen tints.

Ewample 3 The dyestufl' obtained as described in EX- :ample 2 is dissolved hot in 2000 parts of water and the solution is mixed with a solution of chromium fluoride corresponding with 16 parts of C130 the whole being boiled for 24 hours, water being supplied from time to time in place of that evaporated. The new chromium compound may then be salted out. YVhen dry it is a blackish powder, soluble in water. to blackish-brownsviolet 1 solution, in

sodium carbonate solution of 10 per cent. strength to a blackish-green solution and in concentrated sulfuric acid to an olive-brown solution. Wool and silk are dyed by this dye. stuff in an acid bath fast green tints. Cotton and artificialsilk of regenerated cellulose are dyed in a neutral bath or a bath alkaline with sodium carbonate green-grey tints which equalize well.

Ewample 4 The dyestuff from 33 parts of 2-sulfo l- 'hydroxy-u-B-naphtho-phenazine and 22 parts of -nitro-2-amino-l-nheno-l-G-sulfonic acid described in EXample 2 is dissolved in 2000 parts of water and mixed, while hot, with 26 parts of crystallized copper sulfate. copper compound ofthe dyestuff is then obtained by salting out. When dry it is a bronze powder which dissolves in water and in dilute alkalies to a red-violet solution and in concentrated sulfuric acid to a green solution. It dyes cotton and artificial silk of regenerated cellulose in a bath containing Glaubers salt, which may be neutral or alkaline with sodium carbonate, violet tints.

if there be substituted for the 26 parts of copper sulfate an equivalent quantity of nickel suifate therewill be obtained the nickel compound similar to the copper compound. This nickel compound dissolves in water to a red-violet solution, in dilute alkalies to a brown-violet solution and in concentrated sulfuric acid to a green solution, and dyes cotton in a bath containing Glaubers salt greenishviolet tints.

Instead of the naphtho-phenazine used in Examples 14 there maybe used with like results the 2-sulfo-t-hydroxy-a-fi-naphtho-10- tolazine. The dyestuffs are very similar in tint and properties to those described.

Example 5 is isolated. l/Vhen dryit is a blackish powder soluble in water to a brown-red solution, in

The

When coupling is dilute alkalies to a red solution and inconcentrated sulfuric acid to a green solution. It dyes Wool in an acid bath Bordeaux-red tints which become faster when after-treated with copper; when after-chromed, the tint is a dark brown. On cotton, in presence of a chromium there is obtained a brown shade. i

If in this example on completion of the coupling the dyestuff is boiled with a solution of 25 parts of copper sulfate and filtered when cold, there is obtained the complex copper compound of the dyestuff. It is a dark powder which dissolves in water to a red solution, in dilute sodium carbonate solution to a blue-red solution and in concentrated sulfuric acid to a green solution. It dyes vegetable fibres in a bath containing Glaubers salt, and alkaline with sodium carbonate or neutral, violet tlnts.

E wamplc 6 4:? parts of 5 5dihydroxy-7 7 -disulfo-1: l'z2z2-dinaphthazine are dissolved in 500 parts of water with aid of 10.5 parts of sodium carbonate and coupled in presence of sodium bicarbonate and sodium acetate with the diaZo-compound from 44 parts of it-nitro- 1--aminobenzene-2sulfonic acid. When coupling is complete, the lyestufi' of the formula is isolated by salting out and dried. It is a dark powder soluble in water to a blue-red solution; in dilute sodium carbonate solution to a violet solution and in dilute caustic soda solution to ablue-violet solution. In concentrated sulfuric acid it dissolves to a green solution. It dyes wool in an acid bath reclbrown tints and cotton in a bath containing Glaubers salt and alkaline with sodium carbonate red-violet tints.

Example 7 47 parts of 5:5-dihydroxy-7:7-disulfo- 1:1:2:2-dinaphthazine are dissolved in 400 parts of water with aid of 40 parts of calcined sodium carbonate, and the solution is coupled with the diazo-compound from parts of 4-nitro-2-amino-l-phenol-G-sulfonic acid. -After some hours the azo-dyestufl' formed of the formula noa s N=N -s0=H -OH to. T\

noss- N=N- N02 may be salted out. lVhen dry it is a black powder, soluble in water to a blackish-green solution, in dilute alkalies to a blackish-green solution and in concentrated sulfuric acid to a green-blue solution. It dyes cotton in a neutral bath containing Glaubers salt greengrey tints which become fast reddish-grey when after-treated with copper. In presence of chromium salts it dyes cotton grey-green. In an acid bath it dyes wool a blackish-green, which becomes faster when after-chromed; when treated with copper the dyeing becomes grey.

Example 8 The copper complex compound of the dyestuff of Example 7 is obtained by heating the dyestuff formed on completion of the coupling with an ammoniacal solution of copper oxide made from 50 parts of crystallized copper sulfate. This complex copper compound is a black powder soluble in water to a reddish-violet solution, in dilute sodium carbonate solution to a blue-violet solution and in concentrated sulfuric acid to a bluegreen solution. It dyes cotton and artificial silk of regenerated cellulose in a bath containing Glaubers salt, and neutral or alkaline, very fast grey equal tints. It dyes Wool in an acid bath grey tints.

E ammple .9

mium compound of the dyestufl' is obtained.

It is soluble in water to a grey blue solution, in dilute alkalies to a green blue solution and in concentrated sulfuric acid to a green solution. Cotton and artificial silk of regenerated cellulose are dyed in a neutral or alkaline bath containing Glaubers salt very level 1 greenisltgrey tints On-Woolin'an acidibath the dyestulf yields green tints.

In place of the -nitro-2-amino-l-phenol- 6-sulfonic acid used as the diazotizing' com-' ponent in Example 79, there may be used t nitro-Q-amino-l-phenol. In this case dyestuffs are obtained Which have substantiallythe same properties and tints as those of the dyestuffs described above. is somewhat smaller:

4-chloro-2-amino-1-phenol-6+sulfonic acid.

Ewample 1O I A grounding bath is prepared from 18 grams of 5: 5-dihydroXy-7 7 -di s'ulfo-1 1 .2 2=dinaphthazine 50 cc..of caustic sodasolution of e0 per cent. strength perlitre of liquor,

and the warm bathis reduced to dihydroazine by. means ofjgrams of sodium hydrosulfite.

Cotton is handled under'the liquor in this .bath at room temperaturefor 11; hour; It is .thenrinsed, .whereby the azineis re-oxidized: is Development may thenfolloW in known man- ..ner by means of .a. neutralized Idiazo-compound-flWith paraenitrodiazobenzene there is -obtained a brown-olive ,tint,'. While With diazotized 2 .amino 4- .ch'lorobenzene-l 1-" phenylether an olive-brown dyeing is ob' tained.

IVhat We claim is 1. In the manufacture of metalliferous azo-dyes'tuffs containing the azine nucleus,

the steplwhich comprises coupling at least onemolecular proportion of a diazo-com pound of the generalformula Wrerein It stands for a benzene radiclev and mfor a lake-forming'. group in ortho-position to the azo-group, Withthe azines Which-are obtained by. treating Withacids the amdyestuffs of the general. formula V in'which R and R stand for aryl-radicles of-the benzene. and naphthalene series, one g is an.OI-Igr-oup and the other y a hydrogen :1 atom one .2 an O H-gnoup and the other .2

a hydrogen atom, the SO H group andthe .OI-I-groupbeing. in meta-position to each .other.

2. In the...manu-facture of metalliferous' azo-dyestufi'scontaining the azine nucleus;- "mthe step which comprises coupling ataleast.

Their solubility- Instead of the nitroaminophenolsulfonic acid there may be used one 'moleeular, proportion of a diazo-compound of. the generalformula I n N=n-on wherein" ad stands. for a lake-forming group in orthoposition to the azo-group and R stands for a benzene radicle With the v:azineswhich are obtained by treating with acids the. az o-dyestuffs of the general for 1 111113 in Which R and R stan'dfor aryl radicles of thebenzene: and naphthalene series.

3. In the manufacture: of metalliferous azo-dyestuffs containing the azine nucleus, the step which comprises coupling at least one molecular proportion of a diazo-compound of the general formula wherein :2? stands for a lake-forming group in -ortho-position to the azo group, and R stands fora 'benzeneradicle With the azines Which' are-obtained by treating With'acids the azodyestufis of the general formula III=NR1 nmsm m wherein vR-stands for a benzene radicle and the: OH-group stands in ortho-position to the -azo-group,-With the azines Which are obtained by treating With acids'the azo-dyestuffs of the general formula HOQS vSOaH inwhichi R stands for an aryl radicle of the benzenevand naphthalene series.

I. 5:. In-themanufacture of metalliferous azodyestuffs containing the azine nucleus, the

-.step.which comprises coupling two molecular proportions of a (haze-compound of the general formula on R 1 N=NOH wherein It stands for a benzene radicle and the OHgro-up stands in ortho-position to the az0-group with the azines which are obtained by treating with acids the zo-dyestuifs of i the general formula H038 NH SOaH J/ l on on in which R stands for an aryl radicle of the benzene and naphthalene series.

6. In the manufacture of a metalhferous azo-dyestuii' containing the azine nucleus, the

step which comprises coupling two molecular proportlons of (liazotized i-mtro-Zannnolphenol-G-sulfornc acid of the formula with the azine which is obtained by treating with acids the aze-dyestufi of the formula HOaS- NH SO3H.

tn (m 7. In the manufacture of metalliferous azodyestuffs containing the azine nucleus, the step which comprises treating with an agent yielding metal capable of forming lakes with the lake-forming groups of the azo-dyestuffs,

, the azo-dyestuffs which are obtained by cou- 1/ wherein R and R stand for aryl radicles of the benzene and naphthalene series, one 3/ l3 '1 an OH-group and the other T/ a hydrogen atom, one a an SO HgrQup and the other e a hydrogen atom, the SO H-group and the Off-group being in meta position to each other.

8. In the manufacture of metalliferous azodyestuffs containing the azine nucleus, the step which comprises treating with an agent yielding metal capable of forming lakes with the lake-forming groups of the azo-dyestuffs, the aze-dyestuffs which are obtained by coupling at least one molecular proportion of a diazo-compound of the general formula wherein It stands for a benzene radicle and a; for a lake-forming group in ortho position to the azo-group, with the azines which themselves are formed by treating with acids the azoclyestuifs of the general formula wherein R and R stand for aryl radicles of the benzene and naphthalene series.

9. in the manufacture of metalliferous azodyestuf s containing the azine nucleus, the step which comprises treating with an agent yielding metal capable of forming lakes with the lake-forming groups of the azo-dyestuffs, the azo-dyestuifs which are obtained by coupling at least one molecular proportion of a diazo-compound of the general formula wherein R stands for a benzene radicle and w for a lake-forming group in'ortho position to the azo-group, with the azines which themselves are formed by treating with acids the azo-dyestuffs of the general formula wherein R stands for an aryl radicle of the benzene and naphthalene serles.

10. In the manufacture of metalliferous size-dyestuffs containing the azine nucleus, the step which comprises treating with an agent yielding metal of the atomic weigl'it 27 to 66 capable of forming lakes with the lake-forming groups of the azo-dyestuffs, the azo-dyestufis which are obtained by coupling at least one molecular proportion of a diazo-compound of the general formula wherein R stands for a benzene radicle and :0 for a lake-forinlng group in ortho-pos1t1on to the azo-group, with the azines which themselves are formed by treating with acids the azo-dyestuffs of the general formula OH OH wherein R stands for an aryl radicle of the benzene and naphthalene series.

11. In the manufacture of metalliferous azo-dyestuffs containing the azine nucleus, the step which comprises treating with an agent yielding metal of the atomic weight 52 to 66 capable of forming lakes with the lakeforming groups of the azo-dyestuffs, the azodyestuffs which are obtained by coupling at least one molecular proportion of a diazo compound of the general formula wherein R stands for a benzene radicle and m for a lakeforming group in ortho-position to the azo-group, with the azines which are formed by treating with acids the azo-dyestuffs of the general formula 3 R\N=NOH wherein R stands for a benzene radicle and w for a lake-forming group in ortho-position to the azo-group, with the azines which are formed by treating with acids the azo-dyestuffs of the general formula wherein R stands for an aryl radicle of the benzene and naphthalene series.

I OH

13. In the manufacture of metalliferous azo-dyestuffs containing the azine nucleus, the step which comprises treating with an agent yielding metal of the atomic weight 52 to 56 capable of forming lakes with the lake-forming groups of the azo-dyestuffs, the azo-dyestufi's which are obtained by coupling two molecular proportions of a diazocompound of the general formula wherein R stands for a benzene radicle and the OI-I-group stands in ortho-position to the azogroups with the azines which are formed by treating with acids the azo-dyestuffs of the general formula wherein It, stands for an aryl radicle of the benzene and naphthalene series.

14. In the manufacture of a chromiferous azo-dyestufi containing the azine nucleus, the step which comprises treating with an agent yielding chromium the azo-dyestuif which is obtained by coupling two molecular proportions of dia'zotized 4-nitr0-2-amino-L phenol-6-sulfonic acid of the formula HOaS N=N-OH with the azine which itself is formed by treating with acids the azo-dyestuff of the formula N=NO-S 0311 15. Process for the manufacture of metalliferous azo-dyestuffs containing the azine nucleus, consisting in coupling at least one molecular proportion of a diazo-compound of the general formula wherein R stands for a benzene radicle, and at for a lake-forming group in ortho-position to the azo-group with the azines which are -i' formedby treating with acids the azo-dyestufis of the generalformula N=N--n1 wherein R and R stand for aryl radicles,

of the benzene and naphthalene series, one 9 is an OH-group and the other 3 a hydrogen atom, one a an SO H-group andthe others a hydrogen atom, the sogH-group and the OH-group being in meta-position to each other, and then treating the azo-dyestufi's containingthe azine nucleus thus obtained with agents yielding metal capable of forming lakes with the lake-forming groups of the azo-clyestufis.

16. Process for the manufacture of metalliferous azo-dyestuifs containing the azine nucleus, consisting in coupling at least one molecular proportion of a diazo compound of the general formula N=N0H wherein R stands for a benzene radicle, and a? for a lake-forming group in ortho-position to the azogroup,- with-the azineswhicli are formed by treating "with acidsthe azodyestuffs of the general formula f ITT==NR1 wherein Rjand R stand for aryl radicles of the benzene and naphthalene series, and then treating the azo-dyestulf's containing the azine nucleus thus obtained with agents yielding metal capable of forming lakes with'the lake-forming groups of: the azo-dyestuffs= 17 Process for the manufacture ofimetal liferous azo-dyestuffs containing the azine nucleus, consisting in. coupling-at least one molecular proportion of a diazo-compound of the general formula I H i N=N--o11 wherein R stands for a-benzene radicle, and

. a: for a lake-forming group in ortho-position to the azo-group, with the azines which are formed by treating with acids the azo-dyestufls of the general formula V i i V N=N-R1n a i i on a wherein R stands for anaryl radicleof the benzene and naphthalene series, andthen formed by treating with l acids the azo dyev stuffs of the generahformula H 1- I=N-Ri n H wherein R stands for an aryl radicle of the benzene and naphthalene series, and then treating the azo dyestufis containing the azine nucleus thus obtainedwith agents yielding metal of the atomic weight 27' to 66 capable of forming lakes withthelake-forming groups of the a-zo dyestulfs.

.19. Process forthe manufacture of metalliferous azo-dyestuffs containing the azine nucleus, consisting in coupling at least one molecular proportion of a diazo-compouncl of the general formula a i R i 7 N==N-OH wherein R standsfor a benzene radicle, and for a lake-forming group in ortho-positiomtothe azo-group, with the azines which are forinedby treating with acids the amdyestuffs of the general formula wherein R stands for an aryl radicle of the benzene and naphthalene series, and then treating the azo-dyestuifs containing the azine nucleus thus obtained with agents yielding metal of the atomic weight 52 to 66 capable ofzforming lakes with the lake-forming groups of the azo-idyestulf's.

20. Process for. the manufacture of metalliferous azo dyestuffs containing the azine nucleus, consisting-in coupling at least one molecular proportion of a di'a'zo-compouncl V of the general formula N==N-OH wherein R stands for a benzene radicle, and wfor a lake-formmggroup 1n ortho-positlon to the azo-group,with the azines which are formed by treating With acids the azo-dyestuffs of the'general formula' wherein R stands for an aryl radicle of the benzene and naphthalene series, and then vtreating the azo-dyestuiis containing the azine nucleus thus, obtained with agents yielding metalof the atomic weight 52 to 56 capable of forming lakes with the lake-forming groups of theazo-dyestuffs. r

21. Processfor themanufacture of metalliferous azo-dyestuffs containing the azine nucleus,vconsisting in coupling two molecular proportions of a diazo-compound of the general formula wherein stands-for a benzene radicle and the OHi-group stands in ortho-position to the a zoegroup, with the. azines which are formed; by treating with acids the amdyestufl's of the general formula l 0,11 OH v wherein R stands foran aryl radicle of the benzene'and napththalene series, and then treating the azo-dyestufi's' containing the azine nucleus thus obtained with agents yielding metal of the atomic weight 52 to 56 capable of forming lakes with the lake-forming groups of the azo-dyestufls.

22. Process for the manufacture of a chromiferous azodyestufl containing the azlne nucleus,. cons1st1ng in coupling tWo molecular proportions of diazotized l-nitro 2-amino-l-phenol-6-sulfonic acid of the formula N02 with the mine which is formed by treating the azo-dyestufi of theformula j on on with acids, and then treating the azo-dyestu'li containingthe azine nucleus thus'obtained with an agent yieldingchromium 23. As new products the metal compounds of the azo-dyestuffs containing the azine nucleus, which azo dyestuiis are obtained by 1 coupling at least one molecular proportion of a dlazo-compound of the general formula N=NOH wherein R stands for a benzene radicle, and as for a lake-forming group in ortho-position to the azo-group, with the azines which themselves are formed by treatingwith acids the azo-dyestufi's of the general formula wherein R and R stand foraryl radicles of the benzene and naphthalene series, one y is an OH-group and the other y a hydrogen atom, one a an SOgH group and the other 2 a hydrogen atm,.the SO H-group and the OH-group being in meta-position toeach other,'which products form black to brown powders which dissolve in concentrated sulfuric acid to blue-green to green to olivebrown solutions, dyeing vegetable and animal fibres violet to green to grey tints.

24. As new products themetal compounds :1

VN=N-B1 HOsS- NHR2 wherein and R5 stand for aryl radicles of the benzene and naphthalene series, which products form black to brown powders which dissolve in concentrated sulfuric acid to blue-green to green to olive brown solutions, dyeing vegetable and animal fibres violet to green to grey tints.

25. As new products the metal compounds of the azo-dyestufls containing 'the' azine nucleus, which azo-dyestufls are obtained by coupling at least one molecular proportion of a d1azo-compound of the general formula wherein R stands for a benzene radicle, and m for a lake-forming group in ortho-position to the azo-group, with the azines which themselves are formed by treating with acids the azo-dyestulfs of the general formula wherein R stands for a benzene radicle, and

00 for a lake-forming group in orthoposition to the azo-group, with the azmes which themselves are formed by treating with acids the azo-dyestuffs of the general formula l ll=N-Ri Ho3s NH son1 wherein R stands for an aryl radicle of the benzene and naphthalene series, which products form black to brown powders which dissolve in concentrated sulfurlcacid to bluegreen to green to olive-brown solutions, dye- N=N--0H wherein R stands for a benzene radicle, and

m for a lake-forming group in ortho-position to the azo-group, with the azines which themselves are formed by treating with acids the azo-dyestuffs of the general formula OH OH wherein R stands for an aryl radicle of the benzene and naphthalene series, which products form black to brown powders which dissolve in concentrated sulfuric :acid to bluegreen to green to olive-brown solutions, dyeing vegetable and animal fibres violet togreen to grey tints.

l 28. As new products the metal compounds of the azo-dyestuffs containing the azine nucleus and metals of the atomic weight of 52 to 56 capable of forming lakes with the lake-forming groups of the azo-dyestuffs, which azo-dyestulfs are obtained from coupling two molecular proportions of a diazocompound of the general formula wherein R stands for a benzene radicle, and w for a lake-forming group in ortho-position to the azo-group, with the azines which themselves are formed by treating with acids the azo-dyestuffs of the general formula HOaS- NH soar OH OH wherein R stands for an aryl radicle of the benzene and naphthalene series, which products form black to brown powders which dissolve in concentrated sulfuric acid to blue green to green to olive-brown solutions, dyein g vegetable and animal fibres violet to green to grey tints.

V 29. As new products the metal compounds of the azo-dyestuffs containing the azine nucleus and metals of the atomic weight of 52 to 56 capable of forming lakes with the lakeforming groups of the azo-dyestufls, which azo-dyestufls are obtained by coupling two molecular proportions of a diazo-compound of the general formula wherein R stands for a benzene radicle, and

the OH-group 1n ortho-pos1t1on to the amgroup, "ith the azines which themselves are formed by treating with acids the azo-dyes stufls of the general formula N=NR1 wherein R stands for an aryl radicle of the benzene and naphthalene series, which products form black to brown powders which dissolve in concentrated sulfuric acid to bluegreen to green to olive-brown solutions, dyeing Vegetable and animals fibres violet to green to grey tints.

30. As a new product the chromium compound of the azo-dyestuff containing the azine nucleus, which azo-dyestuff is obtained by coupling two molecular proportions of diazotized l-nitro-2-amino-l-phenol-(i-sulfonie acid of the formula with the azine which is itself formed by treating the azo-dyestufi' of the formula With acids, which product forms a black powder which dissolves in concentrated sulfuric acid to a green solution, dyeing the vegetable and animal fibres green-grey to green tints.

In witness whereof we have hereunto signed our names this 31st day of May, 1980.

FRITZ STRAUB. WALTER ANDERAU.