CH684482A5 - Disazo reactive dyes. - Google Patents

Description

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CH 684 482 A5

description

The invention relates to fiber-reactive disazo compounds and processes for their preparation. These compounds are used as reactive dyes in dyeing and printing processes.

The invention relates to compounds of the formula I.

so3h and its salts, in which D represents a radical (a) or (b),

3/3 k (/, 7— or nr4-Q

(a) (b)

each Ri and R3, independently of one another, hydrogen, -COOH or -SO3H, each R2 and R4, independently of one another, hydrogen, Ci-4alkyl or C2-4hydroxyalkyl, and

Q is a heterocyclic reactive radical or one of the following radicals -COCHY2-CH2Y1, -COCY2 = CH2

or -COCH2Y1, wherein

Yi for chlorine, bromine, -OSO3H or -SSO3H, and

Y2 represents hydrogen, chlorine or bromine,

m for 1 or 2,

n for 0, 1 or 2, and

Z stand for the rest «

H

h f with the proviso that the azo groups are each in the ortho position to the amino and hydroxyl group of the disulfonaphthyl radical. The invention also relates to mixtures of the compounds of the formula I and their salts.

Unless otherwise stated, in a compound of formula I any alkyl or alkoxy group can be linear or branched. In a hydroxy substituted alkyl group attached to nitrogen, the hydroxy group is preferably located on a carbon atom that is not attached directly to nitrogen.

The non-fixed sulfo group in the 1-amino-8-hydroxynaphthalene disulfonic acid residue is preferably in 3 position.

Ri preferably represents Ria as -SO3H or -COOH, in particular -SO3H.

R2 preferably represents R2a as hydrogen, methyl, ethyl or 2-hydroxyethyl; more preferred for R2b than hydrogen, methyl or ethyl; particularly preferred for hydrogen.

R3 preferably denotes R3a as hydrogen or -SO3H, in particular -SO3H.

R4 preferably represents R4a as hydrogen, methyl, ethyl or 2-hydroxyethyl; more preferred for R4b than hydrogen, methyl or ethyl; particularly preferred for hydrogen.

Q as a heterocyclic reactive radical is preferably a pyrimidine or triazine radical which carries a labile halogen substituent, in particular fluorine or chlorine.

H

<% H) m

2nd

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CH 684 482 A5

More preferably, Q as a heterocyclic reactive group means a radical of formula (c)

where T for = C - or = N-,

Yc for H, F, Cl, -CN, -CHO, -SRs, -SOR5, -SO2R5 or -SO2F, Zi for H, F, Cl, Br, -NR6R7 or -OR5,

Z2 for F, Cl Br or -®I

A ©

CORg

A © for a non-chromophoric anion,

R5 represents hydrogen, Ci-4alkyl, Ci-4hydroxyalkyl, phenyl or phenyl monosubstituted by carboxy or sulfo,

each R6 and R7, independently, is hydrogen; Ci ^ alkyl, C2-4 hydroxyalkyl, phenyl or phenyl monosubstituted by Ci ^ talkyl, Ci-4alkoxy, sulfo or carboxy; Phenyl (Ci_3alkyl) or Phenyl (Ct-3alkyl), whose phenyl ring is monosubstituted by Ci_4Alkyl, Ci ^ alkoxy, sulfo or carboxy

/ VS ° 2 "X

is; - (CH2) t -SO2-X, -CH2CH2-0- (CH2) t -SO2-X or —V, where t is 2 or 3,

X for -CH = CH2 or -CH2CH2-Y, and

Y stands for hydroxy or a group which can be split off under alkaline conditions, such as, for example, -OSO3H, Cl, Br, -OPO3H2, -SSO3H, -OCOCH3, -OCOCeHs or -OSO2CH3, or -NR6R7 for a piperidine, piperazine, N-methylpiperazine - Or morpholine ring and Rs are hydroxy, -NH2, methoxy or ethoxy.

Ae is preferably a chloride, acetate or methyl sulfate ion.

Y as a group which can be split off under alkaline conditions preferably represents -OSO3H, CI or -SSO3H; particularly preferred for -OSO3H.

X preferably denotes Xa as -CH = CH2, -CH2CH2OH or -CH2CH2OSO3H; more preferably Xb than —CH = CH2 or -CH2CH2OSO3H; especially Xc as -CH2CH2OSO3H.

The radical (c) preferably represents a radical (ci) or (C2),

wherein

Zi 'for Cl, -OCi-2alkyl or -NR6aR7a,

each R6a and R7a, independently of one another, for hydrogen, methyl, ethyl, 2-hydroxyethyl, phenyl or phenyl monosubstituted by methyl, methoxy, sulfo or carboxy, - (CH2) t -S02-Xa or

-CH2CH2-0 (CH2) t -SO2-Xa, or

-NR6aR7a for a piperidine or morpholine ring,

Z2 'for F or CI,

(Ci)

(c2)

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CH 684 482 A5

Yc for hydrogen, Cl, -CN, -CHO or -SO2CH3,

Zi "stands for hydrogen, F or Cl and Z2" for F or Cl.

The following radicals are particularly worth mentioning as radical (ci) or (02):

■ -ff

NH2 NHCH2CH2OH NH (CH2) t-SO2-Xc z; zi z.

-ö. -rt, -K

[= / '\ = / -' N = / _ '

NHCH CH -0- (CH) -SO -X N H) NO

\ _V \ /

/ Z2, Z2 Z9

, N ^ V, N- / h V

C.

N / 'N

W * '~~ C_ / \ j ~ \ N UI3

^ W 'W \ 2

"CH _ / \

% -K 'n

CH. JL \ = / I

3 3 CH2CH3

Z1

L1

or

-4.

H

'SH

m v \

S03H

wherein Z2 ', t and Xc are as defined above, or

,> N ¥ C1. ^ yH.

) - () —F / \

H F H HF Cl F

H

£ - / vv? "3kr" cl j. N - ^ 'Ci i-f ■% "" pf

PI T? r> l / \

Cl F Cl wherein Yc is as defined above.

Y; Cl

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CH 684 482 A5

More preferably, (ci) represents the radical (s) as the radical (ci), in which Zi 'denotes Ci or -NR6aR7a; and (C2) for the radical (02 ') as radical (02), in which Yc' is hydrogen, CI or -CN and Zi "F or CI.

Q preferably represents Qa as radical (c), -COCHY2-CH2Y1 or -COCY2 = CH2; more preferred for Qb as residue (ci) or (C2); even more preferred for Qc as residue (ci ') or (c2') l particularly preferred for Qd as residue (02 ').

The radical (a) preferably denotes the radical (ai),

where -NR4b-Qb is in position 4 or 5;

(ai)

more preferably the rest (a2),

wherein -NH-Qc is in position 4 or 5;

(a2)

in particular the residue (83) as residue (a2), where Qc is Qd. The rest (b) preferably stands for (bi),

J m

'5 k

(CH2) n-NH-Ql wherein n 'is 0 or 1;

(bi)

more preferred for (b2) as residue (bi), where Qb is Qc and the positions are as follows:

(i) n '= 1, -CH2-NH-Qc at position 5; m = 1 and the sulfo group in position 1;

(ii) n '= 1, -CH2-NH-Qc in position 5, m = 2 with the sulfo groups in positions 1 and 7;

(iii) n '= O, -NH-Qc in position 6, m = 2 with the sulfo groups in positions 4 and 8; particularly preferred for (b3) as radical (b2), where Qc is Qd.

D preferably denotes Di as radical (ai) or (bi); more preferably D2 as residue (a2) or (b3); even more preferably D3 as residue (a2); especially D4 as residue (a3).

Preferred compounds of the formula I correspond to the formula Ia la and their salts, in which the azo groups are each in the ortho positions to the amino and hydroxyl group of the disulfonaphthyl radical and D2, Ria, R2b and Z are as defined above.

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CH 684 482 A5

Compounds of the formula Ib h “n oh so-h d3 — N = N are more preferred

N = N

Ib so3h so3h h and their salts, in which D3, R2b and Z are as defined above and in which -NR2b-Z is in position 4 or 5.

Compounds of the formula Ib, in which

(1) R2b is hydrogen;

(2) those of (1), wherein the -NH-Z radical is in the 5-position;

(3) those of (1) or (2), wherein D3 is D4.

The nature of the cation of the sulfo groups and any additionally present car-boxy groups in compounds of the formula I, if these are in salt form, is not a critical factor, but can be any non-chromophoric cation which is customary in the chemistry of reactive dyes . The prerequisite for this is that the corresponding salts fulfill the condition of water solubility.

Examples of suitable cations are alkali metal ions or unsubstituted or substituted ammonium ions, such as, for example, lithium, sodium, potassium, ammonium, mono-, di-, tri- and tetramethylammonium, triethylammonium and mono-, di- and triethanolammonium. Preferred cations are the alkali metal ions and ammonium, of which sodium is particularly preferred.

In general, in a compound of formula I the cations of the sulfo groups and optionally carboxy groups may be the same or different and represent a mixture of the above-mentioned cations, i.e. the compound can also be in mixed salt form.

The invention further comprises a process for the preparation of the compounds of the formula I, characterized in that coupling is carried out on both sides to 1-amino-8-hydroxynaphthalene-3,6- or -4,6-disulfonic acid

on the one hand with the diazonium salt of the amine of the formula II,

D-NH2 II

where D is as defined above,

- and on the other hand with the diazonium salt of the amine of formula III,

where Ri, R2 and Z are as defined above.

Both coupling reactions can be carried out according to a known method. The coupling on the NH2 side is preferably carried out first using an acidic reaction medium, preferably at pH 2-3, to which the coupling on the OH side is connected in a neutral to slightly alkaline medium, preferably at pH 7.5-9 .

The compounds of the formula I can be isolated in a manner known per se; e.g. the compounds can be separated from the reaction mixture by conventional salting out with alkali metal salts, filtered off and dried (in vacuo) at a slightly elevated temperature.

Depending on the reaction and isolation conditions, a compound of formula I is obtained as a free acid or preferably in salt form or as a mixed salt and then contains, for example, one or more of the cations mentioned above. Salts or mixed salts can, however, also be prepared starting from the free acid in a conventional manner and vice versa, or a conventional salting-out process can also be carried out.

III

H

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CH 684 482 A5

The rest Z of the formula

H F

can exist in two isomeric forms with the unfixed fluorine substituent either in position 2 or in position 6 of the pyrimidine ring. Other pyrimidine residues, such as those listed as the meaning of Q and which carry non-fixed substituents, can occur in analogous isomeric forms.

In general, it is preferred to use the isomeric compound mixture obtained as such; a separation into the individual isomers is not necessary, but could, if desired, be carried out according to conventional methods.

The starting compounds of the formulas II and III are either known or can be obtained from known starting materials analogously to methods known per se. Amines of the formula III are obtained, for example, by condensation of compounds of the formula IV,

wherein Ri and R2 are as defined above, obtained with 2,4,6-trifiuoropyrimidine; this condensation is carried out at temperatures between 0 ° -40 ° C, preferably 0 ° -20 ° C, and pH 6-9.

Amines of the formula II are obtained analogously to the above procedure by appropriately condensing a benzene or naphthalene diamine with a compound introducing group Q.

The compounds of formula I and mixtures thereof are reactive dyes; they are suitable for dyeing or printing organic substrates containing hydroxyl groups or nitrogen. The preferred substrates are leather and fiber materials which consist of or contain natural or synthetic polyamides and in particular natural or regenerated cellulose, such as cotton, viscose or cotton wool. The most preferred substrate is textile material that consists of or contains cotton.

The compounds of the formula I can be used in dyeing liquors or in printing pastes by all dyeing or printing processes customary for reactive dyes. Dyeing is preferably carried out using the exhaust process, a temperature range of 30-80 ° C. and in particular 50-60 ° C. being used.

The compounds according to the invention can be used as a single dye or because of their good combinability as a combination element with other reactive dyes of the same class, which have comparable dyeing properties e.g. regarding general fastness properties, pull-out value, etc. can be used. The combination dyeings obtained show good fastness properties as do the dyeings with individual dye.

With the compounds of the formula I, good extraction and fixing values are obtained. The unfixed dye can be easily washed out. The dyeings and prints obtained show good lightfastness. They also have good wet fastness properties, e.g. in terms of fastness to washing, water, seawater and sweat and have good resistance to oxidative influences such as chlorine-containing water, hypochlorite bleach, peroxide bleach and detergents containing perborate.

Particularly noteworthy is the resistance of the dyeings to acid hydrolysis, which is surprising for this class of dyes. For example, when exposed to dilute acetic acid, the dyeings show only slight soiling of undyed accompanying tissue.

The following examples serve to illustrate the invention. In the examples, parts mean parts by weight or volume and percentages mean percent by weight or volume; the temperatures are given in degrees Celsius.

188 parts of 2,4-diaminobenzenesulfonic acid are suspended in 1700 parts of water and dissolved at pH 7 by adding 30% sodium hydroxide solution. At this pH 140 parts of 2,4,6-trifluoropy

IV

example 1

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CH 684 482 A5

added dropwise rimidin. After three hours of reaction at 0 °, the reaction product is diazotized in the usual manner with sodium nitrite.

152 parts of finely ground 1-amino-8-hydroxynaphthalene-3,6-disulfonic acid are sprinkled into the diazonium salt solution obtained above. The pH of the reaction mixture is first raised gradually to 2.5 within two hours by adding sodium acetate solution and then to pH 7.5 by adding sodium carbonate solution. The reaction mixture is salted out with sodium chloride and filtered off. The dye is dried at 60 ° in a vacuum; he has the formula (cited as free acid)

h rpH = H

Vy *

* h and dyes cotton in deep blue tones. These dyeings have excellent fastness properties such as light and wet fastness, and are also resistant to oxidative influences.

Examples 2-42

Analogously to the method described in Example 1, further compounds of the formula I can be prepared using appropriate starting materials, which are listed in the following table. The dyes correspond to the formula (A)

NH-Q

n = n-

h2n oh

"TÎÏ

—N = n

! rr

^ so.h so, h

3rd

nh-z

(a)

for which the variables are listed in the table. In the event that various residues of diazo components are present, i.e. if, for example, Q and Z have different meanings, the coupling reactions must be carried out in successive separate steps, an equimolar amount of each individual diazo component being used at the specific pH as described in Example 1.

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In the table, Z represents the rest of the formula

H F

and Q for the radicals Q1-Q17 in the following meaning: Qi as the radical Z;

Qa as

Cl F

H

Q3 as -w Cl F

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CH 684 482 A5

Q4 as m / C1

CN Cl

C1 v

Q5 as - \ N Qio as __ // Y *

M H

"" 2 KH.

Cl

2 F

, N- / N- /

N QX1 as - ((N

NHCH2CH20H NHCH2CH2OH

Cl F

, N- / N- /

Q7 as —U n Q12 as —0 n

N = (/ \ N == ^ / - A

NO NO

W \ /

Cl F

Qe as —v N Qi 3 as —v n

N = (M

NHCH2CH2SO-Xc NHCH2CH2S02-Xc

Cl F

N- / N— /

Qg as N Q14 as - ^ N

NHCH2CH20CH2CH2S02-Xc NHCH2CH20CH2CH2S02-Xc where Xc is -CH2CH20S03H;

Cl

Q15 as - / s SO, H

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CH 684 482 AS

The compounds of Examples 2-42 can be applied to substrates which consist of or contain cellulose fibers, and in particular to textile material made of cotton, using the customary pull-out method or printing method known per se. Colorings and prints in deep navy blue tones are obtained. The dyeings and prints on cotton show good light and wet fastness properties and are also resistant to oxidative influences.

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table

Compounds of Formula (A) - Examples 2-42

Example No.

Q

Position -NH-Q

r3

Position S03H

Ri

Position -NH-Z

2nd

Qi

5

SO3H

4th

SO3H

5

3rd

Qi

5

SO3H

3rd

COOH

5

4th

Qi

4th

SO3H

3rd

SO3H

5

5

Qi

3rd

H

3rd

SO3H

5

6

Qi

5

SO3H

4th

SO3H

4th

7

q2

5

SO3H

3rd

S03H

5

8th

Qa

5

SO3H

4th

COOH

4th

9

Qa

5

SO3H

3rd

SO3H

5

10th

q3

5

SO3H

3rd

SO3H

4th

11

Qs

3rd

H

4th

SO3H

5

12th

Û4

5

so3h

3rd

SO3H

5

13

q4

5

SO3H

4th

SO3H

5

14

Qs

4th

SO3H

3rd

SO3H

5

15

Qs

5

S03H

4th

COOH

4th

16

Qio

5

SO3H

4th

SO3H

4th

17th

Qio

5

SO3H

3rd

SO3H

5

18th

Qe

3rd

H

3rd

SOsH

5

19th

Qe

5

SO3H

3rd

SO3H

5

20th

Qe

3rd

H

4th

SOsH

5

21

Qu

5

SO3H

3rd

SO3H

5

22

Qu

4th

SO3H

4th

SO3H

5

23

Q7

3rd

H

3rd

SO3H

5

24th

Q7

5

SO3H

3rd

SO3H

5

25th

Ql2

5

SO3H

3rd

SO3H

5

26

Ql2

5

SO3H

4th

so3h

5

27

Qa

3rd

H

3rd

COOH

5

28

Qs

5

SO3H

3rd

COOH

5

29

Qs

3rd

H

4th

SO3H

5

30th

Ql3

3rd

H

3rd

SOsH

5

31

Ql3

5

SO3H

3rd

so3h

5

32

Q9

5

SO3H

3rd

SO3H

5

33

Qg

5

SO3H

3rd

COOH

5

34

Ql4

5

SO3H

3rd

SO3H

5

35

Ql4

5

H

3rd

SO3H

5

36

Ql5

4th

H

3rd

SO3H

5

37

Ql5

3rd

H

4th

SO3H

5

38

Ql5

4th

SO3H

3rd

so3h

5

39

Ql6

3rd

H

3rd

SO3H

5

40

Ql6

4th

SO3H

4th

COOH

5

41

Ql7

4th

H

3rd

SOsH

4th

42

Ql7

5

SO3H

3rd

COOH

4th

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CH 684 482 A5

According to the method described in Example 1, the dyes of Examples 1 to 42 are obtained as sodium salts. Depending on the reaction and isolation conditions chosen or by subsequent measures, they can be prepared in a manner known per se in the form of the free acid or in another salt form or else mixed salt form and then, for example, one or more of the cations listed further in the description contain.

As already mentioned in the introduction to the description, the dyes of Examples 1-42 represent the reactive radical Z of the formula

Mixtures of isomers; they contain the compound in which the unfixed fluorine substituent in the pyrimidine ring is in the 2-position, in addition to the corresponding compound in which the fluorine substituent is in the 6-position, the latter compound normally predominating in terms of quantity. The same applies to the rest Q in the meaning of Qi, Q2 or Q4.

These isomer mixtures obtained as a result of production can be used as such in customary dyeing and printing processes. Isolation of a single isomeric compound is normally not necessary for this.

Possible uses of the dyes described are illustrated below.

Instructions for use A

In a dyebath containing 0.3 part of the dye from Example 1 and 15 parts of Glauber's salt (calcined) in 300 parts of demineralized water, 10 parts of cotton fabric (bleached) are introduced at 40 °. After 30 minutes at 40 °, a total of 6 parts of soda (calcined) are added at intervals of 10 minutes, in portions of 0.2; 0.6; 1,2 and finally 4 parts, keeping the temperature at 40 °. The dyeing is then continued at 40 ° for one hour. The dyed material is then rinsed in running cold water for 3 minutes, then in running hot water for 3 minutes. The dyeing is boiled for 15 minutes in 500 parts of demineralized water in the presence of 0.25 part of Marseille soap. After rinsing in running water (hot for 3 minutes), centrifugation is carried out and the color is dried in a drying cabinet at approx. 70 °. A deep blue cotton dyeing of very good fastness properties is obtained, which in particular shows high wet fastness properties and is stable against oxidative influences.

Application regulation B

10 parts of cotton material (bleached) are added to a dyebath containing 10 parts of Glauber's salt (calcined) in 300 parts of demineralized water. The bath is heated to 40 ° within 10 minutes, then 0.5 part of the dye from Example 1 is added. After a further 30 minutes at 40 °, 3 parts of soda (calcined) are added, after which the dyeing is continued for a further 45 minutes at 40 °.

The dyed material is rinsed with running cold water, then with hot water and washed boiling analogously to that described for regulation A. After rinsing and drying, a deep blue cotton dyeing is obtained which has the properties listed for regulation A.

The dyes of Examples 2-42 or dye mixtures of Examples 1-42 can be used for dyeing in an analogous manner to that described in Regulations A and B. The deep blue dyeings obtained have good fastness properties.

H F

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CH 684 482 A5

Instructions for use C

A printing paste with the ingredients

40 parts of the dye from Example 1

100 parts of urea

350 parts of water

500 parts of a 4% sodium alginate thickener

10 parts of sodium bicarbonate

A total of 1000 parts is applied to cotton material using the usual printing processes. The printed material is steamed for 4-8 minutes at 102-104 ° and then rinsed cold and hot. The fixed cotton material is then washed at the boil (analogous to regulation A) and dried. The navy blue print obtained shows good general fastness properties.

Analogously to regulation C, the dyes of Examples 2-42 or dye mixtures of Examples 1-42 can also be used for printing on cotton. In all cases, deep blue prints with good fastness properties are obtained.

Claims (1)

Claims 1. Compounds of formula I. D-N = N and their salts, in which D represents a radical (a) or (b), (SO, H). or (CH2) n — NR4-Q (b) each Ri and R3, independently of one another, hydrogen, -COOH or -SO3H, each R2 and R4, independently of one another, hydrogen, Ci-4alkyl or C2-4hydroxyalkyl, and Q is a heterocyclic reactive radical or one of the following radicals -COCHY2-CH2Y1, -COCY2 = CH2, or -COCH2Y1, wherein Yi represents chlorine, bromine, -0S03H or -SSO3H, and y2 represents hydrogen, chlorine or bromine, m for 1 or 2, n for 0, 1 or 2, and Z for the rest H H F stand, 14 5 10th 15 20th 25th 30th 35 40 45 50 55 60 65 CH 684 482 A5 with the proviso that the azo groups are each in the ortho position to the amino and hydroxyl groups of the disulfonaphthyl radical. 2. Compounds according to claim 1, wherein Q is a heterocyclic reactive radical for a pyrimidine or triazine radical which carries a labile halogen substituent. 3. Compounds according to claim 1 or 2, wherein D represents a radical of formula (a). 4. Compounds according to any one of claims 1-3, wherein Ri is Ria as -COOH or -SO3H, and R3 is R3a as hydrogen or -SO3H. 5. Compounds according to any one of claims 1-4, wherein R2 is R2a and R4 are R4a, each R2a and R4a, independently of one another, is hydrogen, methyl, ethyl or 2-hydroxyethyl. 6. Compounds according to any one of claims 1-5, wherein Q is Qa as a radical (c), z2 fs (c) z, as -COCHY2-CH2Y1 or -COCY2 = CH2, where Yi is chlorine, bromine, -OSO3H or -SSO3H, and Y2 is hydrogen, chlorine or bromine, ? T for = C— or = N-, Yc for H, F, CI, -CN, -CHO, -SR5, -SOR5, -SO2R5 or -SO2F, Zi for H, F, CI, Br, -NR6R7 or -OR5, Z2 for F, CI, Br or ^ A®, and CORg A © stand for a non-chromophoric anion, R5 is hydrogen, Cwalkyl, Ci_4hydroxyalkyl, phenyl or phenyl monosubstituted by carboxy or sulfo, each R6 and R7, independently of one another, is hydrogen; Ci-4 alkyl, C2-4 hydroxyalkyl; Phenyl or phenyl monosubstituted by Ci-4alkyl, Ci-4alkoxy, sulfo or carboxy; Phenyl (Ci-3alkyl) or phenyl (Ci-3alkyi), the phenyl ring of which is monosubstituted by Ci_4alkyl, Ci-4alkoxy, sulfo or carboxy; - (CH2) t -SO2-X, SO - X -CH2CH2-0- (CH2) t-S02-X or ■ \ 2, where t is 2 or 3, X for -CH = CH2 or -CH2CH2-Y, and Y represents hydroxy or a group which can be split off under alkaline conditions, or -NR6R7 is a piperidine, piperazine, N-methylpiperazine or morpholine ring, and Rö is hydrogen, -NH2, methoxy or ethoxy. 7. Compounds according to claim 1, which correspond to the formula la Ia and their salts, in which the azo groups are each in the ortho positions to the amino and hydroxyl groups of the disulfonaphthyl radical, 15 5 10th 15 20th 25th 30th 35 40 45 50 55 CH 684 482 A5 Z is as defined in claim 1, Ria for -COOH or -SO3H, R2b for hydrogen, methyl or ethyl; and D2 represents a radical (a2) or (b3), SCLH T wherein -NH-Qc is in the 4- or 5-position; (& 2) (Sn where m is 1 or 2 and n 'is 0 or 1, (CH2) n-NH-Qd (b3) and the substituents occupy the following positions: (i) n '= 1, -CH2-NH-Qd at position 5; m = 1 with the sulfo group in position 1; (ii) n '= 1, -CH2-NH-Qd at position 5; m = 2 with the sulfo groups in positions 1 and 7; (iii) n '= 0, -NH-Qd at position 6; m = 2 with the sulfo groups in positions 4 and 8; Qc is a residue (ci ') or (02'), and Qd represents a radical (c2 '), where (er) stands for (ci) and (C2') stands for (C2), wherein Zi 'for chlorine or -NR6aR7a, each Röa and Rza independently, for hydrogen, methyl, ethyl, 2-hydroxyethyl, phenyl, phenyl monosubstituted by methyl, methoxy, sulfo or carboxy, - (CH2) t -S02-Xa or —CH2CH2-0 (CH2) t— S02-Xa, where t is 2 or 3, and Xa stands for -CH = CH2, -CH2CH2OH or -CH2CH2OSO3H, or -NR6aR7a for a piperidine or morpholine ring, Z2 'for F or CI, Yc 'is hydrogen, CI or -CN, and each Zi "and Z2" are F or CI. 2nd (Ci) (c2) 16 5 10th 15 20th 25th 30th 35 40 45 50 55 60 65 CH 684 482 A5 8. Compounds according to claim 7, which correspond to the formula Ib, h2n oh so3h d3 — n = n n = n Ib so3h so3h h and their salts, in which R2b and Z are as defined in claim 7, and -NR2b-Z is in the 4- or 5-position, and Ü3 means a radical (a2) as defined in claim 7. 9. Compounds according to claim 8, wherein R2b is hydrogen and -NH-Z is in the 5-position. 10. A process for the preparation of compounds of formula I, defined in claim 1, characterized in that coupling on both sides to 1-amino-8-hydroxynaphthalene-3,6- or -4,6-disulfonic acid on the one hand with the diazonium salt of the amine of the formula II, D-NH2 II wherein D is as defined in claim 1, and on the other hand with the diazonium salt of the amine of the formula III, iii h wherein Ri, Ra and Z are as defined in claim 1. 17th