DE2149513A1 - Azo dyes - Google Patents

Description

DR. BERG DIPL.-ING. STAPF PATENT Attorneys £ | 4 si Q I v *

8 MUNICH 8O, MAUERKIRCHERSTR. 49

Df. Berg Dipl.-Ing. Stapf, 8 MOndien 80, MauerfcircherstraSe 45

Attorney's File No. 21 541

4 »OKt

Yours, your letter and sign. Date "" ^ll

UGINE KÜHLMANN
Paris, France

Azo dyes

The present invention relates to particularly interesting new azo dyes for dyeing or finishing of leathers of various tans. It is known that the monoazo dyes that differ from resorcinol derive, have practically no affinity for leather.

In the French patent specification 1 165 637 and the additional patent 72 418 monoazo dyes are described, which are derived from 2,4-dihydroxy-benzophenone and 2,2 *, 4,4'-tetrahydroxy-benzophenone. These dyes however, they have only a low affinity for leather and the dyeings obtained are opposite

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Washing is not sufficiently durable; on the other hand, the preparation uses the benzophenones listed above large amounts of phosphoric acid, phosphorus oxychloride or boron trifluoride and can, as a result, only in special and expensive fixtures. In the French patent specification 1 188 062 are also Monoazo dyes have been described which are derived from the 3,3'-dihydroxydiphenylamine. These dyes have a good affinity for leather; however, the dyeings obtained are not resistant to washing.

In accordance with the present invention it has now been found that the dyes of the general formula X R, R

(D

and their oxidized., nitrosated and metallhal term derivatives have an excellent affinity for leathers of different tanning, on which they give strong and - especially to light, wet tests, solvents, rubbing and grinding - very stable shades. In the formula (I), both X are identical and denote hydrogen atoms or hydroxyl groups, R _{1 and R 3 can be} identical or different and a

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Denotes hydrogen atom or a hydroxyl, alkyl or aryl group, R denotes a hydrogen atom or an alkyl or aryl group, Z denotes a hydrogen atom or any substituent, for example a solubilizing radical, a nitro or hydroxyl group, η is 0 or 1 and A denotes the residue of a diazotizable aromatic amine A-NH ₂ F which contains at least one sulfonic acid or carboxylic acid residue. The invention also includes dyes which are obtained by salt formation of the dyes of the formula (I) with amines or ammonium salts.

These dyes can be obtained by coupling the diazo compound of a molecule of the primary aromatic amine A-NH, with a molecule of a coupler of the formula X R, / R,

¹ /

N C -4 </ ^) - OH (II)

J \ -

i Z

in which the symbols X, Z, R ₁ , R ₀ , R, and η have the same meanings as in the formula (I) are prepared. The coupling takes place in the ortho position to a hydroxyl group.

The amines A-NH ₂ can belong to a wide variety of groups, such as the benzene, naphthalene, heterocyclic or azo group, but must have at least one sulfonic acid or carboxylic acid radical. It can

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for example the aminobenzene or JVminonaphthalene

Aminosulfonic acids, the aminophenol or naphthol sulfonic acids and the amino-diphenylamine-sulfonic acids and their substituted ones Derivatives are called.

Certain couplers of formula (II) are known; as such, the 2,4,2 ', 4'-tetrahydroxy-diphenylmethane, 2,4,2', 4'-tetrahydroxy-ß, ß-diphenylpropane and 2,4-dihydroxybenzhydrol to be named. The others are new and thus part of the invention. According to the nature of the substituents, the couplers of the formula (II) can be prepared by one or another of the following processes will:

a) Condensation in a strongly acidic environment of 2 molecules of resorcinol with one molecule of an aldehyde or one Ketones to the coupler of the formula

OH R 'OH

.. J ι ^Σ J-.

_H0 _ ^ / X _{1 c} / V-OH (Ha)

^RI 2

in which R 'and R' ₂ each represent a hydrogen atom or an alkyl or aryl radical.

b) condensation in an alkaline environment of a molecule of resorcinol with a molecule of a benzaldehyde or of a phenone to form the coupler of the formula

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(lib)

to obtain.

c) Condensation in an aqueous medium of 2 molecules of resorcinol and 2 molecules of aldehyde or ketone with one Molecule of a chlorohydrate of a primary or secondary amine or with a molecule of ammonium chloride,

to the couplers of the formula OH R, R

7 ^

HO —T ^x > CNC

(lic)

to obtain.

The dyes of the formula (I) are soluble in water. They dye the leathers of various tannings in brown, black and green shades that are strong, fresh and - in particular, very resistant to light, wet tests, solvents and mechanical influences. The nitrosation of the dyes of the formula (I) has a hypsochromic effect on the hue of the starting dye. It may be in an acid medium, preferably a temperature of -10 to +90 ⁰ C, preferably 0 ° at a pH of 0.5-4 and - 30 ° C are performed. The amount of nitrous acid used can vary depending on the shade desired. The nitrosation takes place

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in ortho position to a hydroxyl group. The oxidation of the dyestuffs of the formula (I) gives dyestuffs which dye leather of various tannings in shades that are more brown than the original shade; although the oxidation of the previously nitrosated dyes of the formula (I) also has a weak hypsochromic effect on the hue. The oxidation can in a neutral or acidic medium ^1, preferably alkaline .Milieu be carried out, for example in the presence of ammonia or an alkali metal hydroxide, carbonates or bicarbonate. In particular, air, the hypochlorites, peroxides such as hydrogen peroxide, persalts such as sodium or potassium permanganate, sodium or potassium dichromate or metallic oxides such as manganese dioxide can be mentioned as oxidizing agents.

The hue of the dye obtained may vary slightly depending on the nature and amount of the dye used Oxidizing agent vary.

The dyes of the formula (I) in which the radical A in the ortho position to the azo bridge forms a complex-forming Radical, for example a hydroxyl, amino, alkoxy, acyloxy or carboxy radical, and the nitrosated Derivatives of the dyes of the formula (I) can be converted into metal complexes such as iron, copper, chromium, cobalt or Nickel complexes. The metallization can be carried out in an aqueous medium by methods known per se

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or in a mixture of 'Passer and an organic one Solvents such as alcohols, polyols, formamide and dimethylformamide at a temperature of 10 - 150 ° C and a pH of 1-11, preferably 5-8. As metallization means, for example the metal chlorides, fluorides, acetates, sulfates, oxides or hydroxyde are called, as well as the alkali chromates and bichromates. The metal-containing complexes obtained in this way give leather shades that have excellent resistance to light in particular.

The dyes of the formula (I) and their nitrosated, oxidized or metal-containing derivatives can also with With the help of an amine or a quaternary ammonium salt. As amines, for example, the Arylguanidines, Cyclohexylamiη and Dicyclohexylamine to be named. The salts obtained are insoluble in water, but soluble in organic solvents, especially in the alcohols and diols. They can be used for the dyeing finishing of leather, for example for the aniline dyeing refinement of previously dyed or hides not previously dyed and for the refinement of leathers with improved or artificial coloring, as well as for spray gun dyeing of full-grain leather, on which they have very fresh and - especially to light and wet rubbing - very resistant transparent color

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Giving fabrics, being used.

The following examples illustrate the invention. Parts are parts by weight, unless otherwise stated.

Example 1

18.9 parts of 2-aminophenol-4-sulfonic acid are diazotized in the customary manner and within 30 minutes the diazo compound obtained passes into a solution at pH 11 of 23.2 parts of 2, 4, 2 ', 4' -Tetrahydroxy-dipheny! methane in 500 parts of water to which 40 parts of sodium carbonate were added at 5 ° C.

The coupling is very quick. When it is finished, the "ionoazo dye" is precipitated by adding sodium chloride and hydrochloric acid to pH 7, filtered and dried. The sodium salt of [5-sulfo - 2-hydroxy-benzene3 - <1 azo 5> - f2,4,2 ', 4 - Tetrahydroxy-diphenylmethane]] colors the leather in different ways Tanned in brown-orange shades, which are particularly resistant to bottles, light and solvents are.

The dyeing yield of this dye is about twice as great as that of the corresponding monoazo dye, which starts from 7, 4,?. ' , 4 '-Tetrahvdroxv-benzophenone (patent of addition 72,418 last to French Patent 1 1Γ5 637, page 2 ^p eisr> iel the table) obtained wi rd; its constancy rreaenü ^ er "nsrhon is outside the ^ erdm ^ a

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clearly

To isolate the dye from the reaction medium, you can also ^{pulverize the solution of the dye in a 1} bottle in which a stream of hot air circulates.

Table I below summarizes other examples of the dyes prepared according to Example 1, wherein but the 2- »mino-phenol-4-sulfonic acid by the diazotizable Pmine A-NF-, the j η listed in the second column are replaced.

^m abelle T

Rex- (game

Arnin A-

Shade on leather

l- £ mino-u-naphthol ~ 3, fi-disulfonic acid j brown-red

4-Amino-4'-nitro-diphenylamine-2'-sulfonic acid

2-Amino-6-nitro-ph.enol-4-sulfonic acid

2 ~ 7 * mino- ^ nitro-phenol-fi-sulfonic * »Ure

brown-red

brown to strong red

brown-red

£ 4 ^l -nitro ~ 2 ^l -sulfo-diphenvlaminI] <4 azo 7> - ■ D- ^ mino-3,6-d.isulFo- dark brown > 8-hydroxy-naphthalene] ■ greenish i

Verrrl r Lr * "''. \ Ν · < ^:

; tr> fF: ·. i ·? ·!> -; ». j f j f-r · ϊ eil > ti

0 i) H i ¹ I /! fi 7 f;

t: oFf ^r lf>r; ^p t 'ί r.pi el er.?. dor

ΠΡ. ^ f? τ-Ή.γ; · -. dp γ Pn

^u nrti'M oi.ru?r vLo. 1

BATH ORIGINAL

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superior resistance to V7aschen.

Example 7

If, on the one hand, 2-amino-phenol-4-sulfonic acid is used in Example 1 by 31.9 parts of 1-amino-B-naphthol-3,6-disulfonic acid and on the other hand 2,4,2 ', 4'-tetrahydroxydiphenylniethane by 21.6 parts of 2,4-dihydroxy-benzhydrol replaced, one obtains the disodium salt of [3, 6-disulfo-8-hydroxy-naphthalene ^ I - <1 azo 5> - £ * 2,4-dihydroxy-

the

benzhydrolj, the leather of various tannings in - compared to usual samples - very resistant brown-red
Shades of color.

Table II below lists other examples of monoazo dyes made by coupling the diazo compound
of a diazotizable amine A-FH ₂ wit the 2,4-dihydroxybenzhydrol were obtained in an alkaline medium.

Table II

A-KH ₂ ! Hue on

leather

8 | 2-? Inino-5-sul.fo-benzoic acid brown-yellow

9; 2-amino-naphthalene-6-sulfonic acid brown-orange

10; l-Amino-naphthalip-4-sulfonic acid, bra \ in-oranae

11 "2-Amino-phenol-4-sulfonic acid. Brown-orange

12 ß-Mitro-2-anino-phenol-4-sulfonic acid brown-pchvarz-

blue

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Ipi comparison to yours in the first row of the table of Page 3 of the French patent specification 1,165,637 has the dye of the example 12 above has the advantage of a better dyeing yield and better resistance to washing.

Example 13

15 parts of an aqueous 20 Be solution of hydrochloric acid are added to the solution of a diazo compound of 17.3 parts of p-sulfanilic acid and then a solution of 23.2 parts of 2,4,2 ', 4'-tetrahydroxydiphenylmethane at pH 11 in 600 parts of water. ^? "to allowing the coupling reaction part, 2 hours to proceed and then returns within 1 hour a solution of 11 parts of sodium carbonate in 110 parts of t <\ ater to. The coupling is beencet very quickly. ^r 4an isolates the jVPulfo-benzolJ ~ -Cl azo 5 > - jj2, 4, 2 ", 4'-tetrahydroxy-diphenylTnethanj in the form of the sodium salt by customary methods. This dye dyes the leathers of various types in brown-orange, particularly those that are resistant to common samples.

Example 14

^T-7 If, in the previous example, the p-sulfanilic acid is replaced by 21, P ¹¹¹ OiIe l- ^A ninn-4-nitro-benzene-2-sulfonic acid, one obtains: one r'an Li ¹ "^ tro- 2 - Riilfo-benznlj

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<1 azo 5> - [j2,4,2 ', 4 ^I -tetrahydroxydiphenylmethaneJ in the form of the sodium salt. This dye dyes the leathers of various tans in redder shades.

Example 15

If in Example 13 the 2,4,2 ', 4'-tetrahydroxy-dipheny! Methane by 21.6 parts of 2,4-dihydroxy-benzhydrol replaced, the ^ 4-sulfobenzeneJ - 4I azo 5> is obtained Fe ^ 2,4-dihydroxy-benzhydrolJ in the form of the sodium salt; this dye has a similar hue and properties.

Table III below gives other examples of monoazo dyes on, which is obtained by coupling 2,4-dihydroxybenzhydrol with diazo compounds from in the second Amines A-NH- indicated in the column were obtained in an acidic medium became; they are obtained in the form of the sodium salt.

™ Table III

hf-.

! play * "" - """" 2

Amine A-HH,

Shade on leather

l ~ Amino-2,5-dichlorobenzene-4-, -n _-, j,

₁₄ - ..! brown-yellowish

sulfonic acid

1 ¹⁶

j öuiiuasiure j

I 17 i l-ATTiino-4 ~ chloro-benzene-3-sulfone-,

^: acidic brown-yellowish!

l-amino-4 "chloro-benzene-2-E! ulfon-

acid brown-aelJilich

19 ι l-amino-4-nitro-benzene - 2-sulfone-

acidic brown-reddish

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- J.J -

Example 20

In the solution of the diazo compound of 17.3 parts of p-sulfanilic acid one passes gradually a solution of 29.75 parts of bis (2,4-dihydroxy-benzyl) amine chlorohydrate in 200 parts of water. After coupling for 4 hours at about pH 2, the pH is brought to the fore by adding an aqueous solution Sodium carbonate solution to 3.5.

When the coupling is complete, the £ "4-sulfobenzene is isolated <1 azo 5> - [bis- (2,4-dihydroxy-benzyl) -amine] in the form of sodium sulfonate. This dye stains the leather of various tans in very persistent brown-yellow color tones.

The bis- (2,4-dihydroxybenzyl ) amine chlorohydrate can be prepared as follows. 110 parts of resorcinol are dissolved in 150 parts at 60.degree Water and then passes 27 parts of ammonium chloride and 100 parts of a 30% aqueous formaldehyde solution a. The mixture is heated to 85 ° C. and this temperature is maintained for 2 hours. You get such a clear, amber solution of bis (2,4-dihydroxy-benzyl) amine chlorohydrate (in quantitative yield). This solution is very stable and can be added by adding to be diluted by water in any amounts. When neutralized to pH 7, a white precipitate is obtained of bis (2,4-dihydroxy-benzyl) amine, a poorly stable product that becomes

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dissolving sodium hydroxide again.

Example 21

If in Example 13-the 2, 4, 2 ', 4'-tetrahydroxy-diphenylmethane through 26 parts 2, 4, 2 ', 4'-tetrahydroxy-ß, ßdiphenylpropane replaced, one obtains the Q-SuIfo-benzene / J - <1 azo 5> - £ 2,4,2 ', 4' -Tetrahydroxy-ß, P-dipheny! Propane) in the form of the sodium salt. This dye dyes the leathers of different tans in slightly more yellow shades.

Example 22

If in Example 13 the 2,4,2 ', 4'-tetrahydroxy-dipheny! Methane by 23.2 parts of 2,4,3'-trihydroxy-benzhydrol replaced, one obtains the £ 4-sulfobenzeneJ < 1 azo 5> - £ 2,4,3'-trihydroxy-benzhydrol3 in the form of Sodium salt. This dye dyes the leathers of different tans in slightly more yellow shades. The 2,4,3'-trihydroxybenzhydrol used in this example can be prepared as follows: 110 parts of resorcinol are dissolved in 1200 parts of water and set Share a 40% sodium hydroxide solution and then 122 parts of 3-hydroxy-benzaldehyde. One heats up up to 70 ° C and maintains this temperature for 3 hours. This falls through the addition of 20 ° Fe-hydrochloric acid 2,4,3'-trihydroxy-benzhvdrol.

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Example 23

If in Example 13 the 2,4,2 ', 4'-tetrahydroxy-diphenylmethane by 26.1 parts of 3'-nitro-2,4-dihydroxybenzhydrol replaced, one obtains the / ~ 4-sulfo ~ benzene7- <1 azo 5> - / j3'-nitro-2,4-dihydroxy-benzhydrolj, das dyes the leather of various tans in brown shades.

Example 24

As indicated in Example 13, a monoazo dye is prepared starting from 17.3 parts of p-sulfanilic acid and 23.2 parts of 2,4,2 ', 4'-tetrahydroxy-diphenylmethane. When the coupling is complete, the mixture is heated to 70 ° C. and 100 parts of a 20 ° Be ammonia solution are added then 5 parts of a 35% strength hydrogen peroxide solution. The mixture is heated to 70 ° C. for 1 hour and then isolated the oxidation product. This dye colors the leathers of different tans into slightly brown ones Shades than those obtained with the dye of Example 13.

Example 25

The diazo compound is coupled from 17.3 parts of p-sulfanilic acid with 23.2 parts of 2,4,2 ', 4'-tetrahydroxy-diphenylmethane; when the clutch is finished, you bet

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35 parts of a 2O ⁰ Be hydrogen chloride solution and then gradually within 30 minutes a solution of 21 parts of sodium nitrite in 42 parts of water. The mixture is then stirred at 10 ° C. until the nitrosation has ended. Touching paper impregnated with potassium iodide and starch reveals that the nitrous acid has been consumed. The resulting ^ 4-sulfo-benzo! Q- <1 azo 5> -f2,4,2 ', 4'-tetrahydroxy-3,3.5.5 -trinitroso-diphenylmethane is then isolated. This dye dyes the leathers of various tannings in shades that are clearly more yellow than those obtained with the dye of Example 13.

The mitt-sized shades tetrahydroxy-S-nitroso-diphenylmethanJ ^ between - if you 7 parts of sodium nitrite used instead of 21 parts, we obtain the / _4-sulfo benzolJ- <1 azo 5 - £ J 2.4, 2 ¹ ^ ' those obtained with the dye of Example 13 and those obtained with the dye nitrosated with the aid of 21 parts of sodium nitrite.

Example 26

If in Example 25 p-sulfanilic acid by 4-nitro-l

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Replaced amino-benzene-2-sulfonic acid, one gets Dye that dyes the leathers of various tans in brown shades.

Example 27

As indicated in Example 25, the monoazo dye is nitrosated, according to the information in Example 13 starting from 17.3 parts of p-sulfanilic acid and 23.2 parts

len 2,4,2 ', 4'-tetrahydroxy-diphenymethane was obtained. The mixture is heated to 70 ° C. and then 100 parts of an aqueous 20 ° Re ammonia solution are added and then 5 parts of a 35% hydrogen peroxide solution. The mixture is kept at 70 ° C. for 1 hour and the dye is then isolated by customary methods. He dyes leather in a variety of ways Tanned in slightly yellower and stronger shades than those obtained with the dye of Example 25.

Example 28

One oxidizes like I? < previous example the nitrosated dye described in Example 26. You get such a dye, which makes the leathers different Gerbuncipn colors in yellower and stronger shades than those obtained with the dye of Example 26 became.

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Example 29

Fan nitrosated, as indicated in Example 25, after the data of Example 13 obtained from 17.3 parts of p-sulfanilic acid monoazo dye. One gives 16.3 parts of iron (III) chloride, dissolved in 75 parts of ™ water, and brings the pH by adding a 36 ° Ee solution of Sodium hydroxide to 5.5. fan lets react until the Formation of the iron (III) complex is complete, which can be detected by paper chromatography, the dye precipitates by adding sodium chloride, filtered and dried. The complex obtained dyes the leathers in different ways Tanned in brown-yellow shades that go green and have excellent resistance to it usual samples.

Example 30

The monoazo dye is prepared according to the information in Example 15, that from the coupling of the niazo compound of 17.3 parts of p-sulfanilic acid and 21.6 parts of 2,4-dihydroxybenzhydrol was obtained. 35 parts of a 20 ° Be solution of hydrochloric acid are added to the solution of the dye and then passes a solution of 7 parts of sodium nitrite in 14 parts of water within 30 minutes a. The mixture is then stirred at 10 ° C. until fitrosation is complete, and isolates the dye nitrosated by the customary methods. He colors the leather in different

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dener tanning in slightly redder shades than those obtained with the dye of Example 25.

Example 31

If in the previous example p-sulfanilic acid Replaced by 4-nitro-l-aminobenzene-2-sulfonic acid, a nitrosated dye is obtained, which the leather different tannins in slightly redder shades.

Example 32

^M to nitrosated, as indicated in Example 30, the monoazo dye obtained in Example 15 and then oxidized by. WasserPtoffperoxyd according to the information in Example 27. The dye thus obtained dyes the leather of various tannings in slightly redder shades than those obtained with the dye of Example 27.

Example 33

The monoazo described in Example 19 is nitrosated dye as in Example 30 and then oxidized as in Example 27. A dye is obtained which has the Leather of various tans in slightly redder tones than that with the nitrosated and oxidized dye of nn.Example 3 2 obtained colors.

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Example 34

18.4 parts of 4,4'-diamino-diphenyl are tetrazqtated in the customary manner and a solution of 31.9 parts of 1-amino-8-naphthol-3,6-disulfonic acid is then added to the solution of the tetraazo compound in the course of 1 hour 200 parts of water at pH 7 are added. Fan stirs for 1 hour and then slowly passes in an aqueous solution of sodium carbonate in order to bring the pH to about 3. When the coupling is complete, 40 parts of sodium carbonate are added and then gradually the solution of the diazo compound of 17.3 parts of p-sulfanilic acid. When the coupling has ended, a solution of 21.6 parts of 2,4-dihydroxybenzhydrol in 400 parts of X ^iT water at pH 8 is then added to the diazodisazo compound. The trisazo dye obtained is isolated according to the usual methods. Ex dyes the leather of various tannings in black, somewhat greenish shades.

Example 3 5

If in the previous example the 2,4-dihydroxybenzhydrol by 23.2 parts of 2, 4, 2 ', 4'-tetrabydroxy-di-phenylmethane replaced, one obtains a dye that turns the leather of various tannings into black, something colors more greenish hues.

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Example 36

T * ⁷ hen to the 2,4-dihydroxy-benzhydrol in Example 34 by 26 parts of 2,4,2 ', 4'-tetrahydroxy -. ^ Ss-diphenylpro-

the

When replacing pan, one obtains a dye which is different from one another Tanned in black, slightly greener shades of color.

Re-example 37

T ^'7 a hen in Example 34, the solution of the 2,4-Dihydroxybenzhydrols through a solution of 29.75 parts of bis (2,4-Dihydroxy-benzyl) -amine hydrochloride in 200 parts of water

replaced, one obtains a dye that turns the leathers of different tans into black, greener ones Shades of color.

Example 38

66.1 parts of bis (ß-ITydroxy-ethylaminosulfonyl) are tetrazotized -bis- (3-amino-4-sulfo-phenylaminosulfonyl) -copper phthalocyanines, their production in example

9 French Patent 1,530,577 describes and gives then within 30 minutes, the solution of the Tetraazoverbindung to a solution of 23.2 ^m rush 2,4,2 ', 4'-Tetrahvdroxy-diphenylmethane iswasser in 400 parts of T ^ at pH 11 zn, cOm 20 parts of sodium carbonate were added.

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When the coupling has ended, the dyestuff is isolated by the usual methods. F, r dyes the leather of various tannings in dark green-yellow shades.

Example 39

If the 2,4,2 ', 4'-tetrahydroxy-diphenylmetban in the previous example is replaced by 26 parts of 2,4,2', 4'-tetrahydroxy-β _f β-diphenylpropane, a dye with similar properties is obtained.

Example 40

If you have the 2,4,2 ', 4'-tetrahydroxy-dipheny! Methane in Example 38 by 21.6 parts of 2,4-dihydroxy-benzhydrol replaced, one obtains a dye, deryLeather of different tanning in dark green, a little less yellow Shades of color.

Example 41

45.4 parts according to Example 1 are dissolved in 500 parts of water obtained dye (sodium salt) and adds 8.2 parts of iron (III) chloride as a solution in 50 parts of water. The pH is brought to 5.5 and by adding an aqueous solution of sodium hydroxide. lets stir for 2 hours. The iron complex of the monoazo dye of Example 1 is isolated by the customary methods. It colors the

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Leather of various tannins in dark brown to strong yellow shades.

Table IV below combines other examples of metal complexes made by conventional procedures from dyes described in the previous examples. The cobalt and chromium complexes are Ir2 Eoiuplexes; they contain a metal atom, bound to 2 molecules of dye.

Table T.V

Jexample

metal

Dye of the example

Shade on leather

! 45
! 46
! 47
! 48
^! 49

; Fisen
IF.isen
copper

copper
copper
^: Copper
nickel
nickel

5O nickel 51 cobalt 52 iFickel 53 nickel 54 iNickel 55 t
! F, isen 56 ■ Fisen

4 5 1

4 5

12 1

5 5 8

11 12

11 12

Brown

dark brown yellow
brown-red brown-red brown-red brown-red j brown-orange j

brown to black-blue brown-red brown-red brown-orange brown-orange j

S strong brown

j red

! brown greenish. brown-yellow

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The dyes of Examples 44 and 47 above show affinity for the leather and durability compared to washing, which is clearly superior to that of the corresponding copper complexes starting from 2,4,2 ', 4'-tetrahydroxy-benzophenone or 2,4-dihydroxy-benzophenone can be obtained.

Example 57

48.3 parts of the sodium salt of the example are dissolved 12 prepared dye in 2000 parts of water at 60 ° C. A solution is passed within 1 hour of 23.9 parts of di-ortho-tolylguanidine in 250 parts Water and 11 parts of a 10 ISF solution of hydrochloric acid a. The dye is filtered off in the form of the amine salt, washed with water and dried. He is completely insoluble in water, but readily soluble in alcohols such as ethanol and in the monomethyl ether of ethylene glycol. Its dilute alcoholic solutions are brown.

Example 58

If you take the 23.9 parts of di-ortho-tolvlquanidine in Example 57 replaced by 21.2 parts of diphenylguanidine, a dye is obtained in the form of the amine salt similar properties.

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Example 59

If you take the 23.9 parts of di-ortho-tolylguanidine in Example 57 replaced by an equivalent amount of a technical mixture of alkyldimethylbenzylammonium chloride, of which the alkyl group is a linear or branched alkyl radical with 12 carbon atoms, a dye is obtained in the form of the amine salt with similar properties.

Table V below combines other examples of dyes saponified with di-ortho-tolylguanidine.

Table V

at
game Dye of the example j hue of the thinned ■
; ten alcoholic
¹ solutions 60 11 brown-orange 61 1 brown-yellow 62 4th Brown 63 5 Brown 64 41 brown-yellow 65 48 brown-yellow

Example 66

A sample of 100 parts of pure chrome box calf leather is rinsed, neutralized and then rinsed again (calculated on the furrowed leather). This leather is put into a walker which has a solution of 1 part of the

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Dye of Example 27 in 500 parts of water 60 ° C. It is drummed for 45 minutes at 60 ° C. and conducted then a feed suspended in 50 parts of water with the aid of a conventional dispersant and still rolls 30 minutes. The boxing calf leather is turned into a

Fresh brown-yellow color, which is resistant to light, washing and solvents.

Example 67

100 parts of pure chrome suede are soaked in the presence of a little ammonia, it is rinsed and passed into a walker which contains a solution of 6 parts of the dye of Example 27 in 2000 parts of water at 60.degree. It is drummed for 1 hour at 50.degree. C., then 3 parts of formic acid are passed in and drummed for a further 30 minutes. The leather is dried and subjected to the usual mechanical treatments. The result is a fresh brown-9 ^e l ^ben shade which is resistant to light, washing, solvents and grinding.

Example 68

Bring 2 layers of a 10 part solution

Dye of Example 64 in 100 parts of Γίοηο-methyl ether of ethylene glycol and 250 parts of ethanol on a full-grain vachette skin. One dries and then applies a layer of binder, given

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if stained with the previous solution, click on to the Increase opacity. You dry, apply a new layer of binder and dry again. Man fixed with a formalin solution, dries, smooths and plates. A uniformly colored leather is obtained in this way in a brown-yellow shade that is particularly resistant to light, solvents, washing and mechanical Actions is. The finish obtained is particularly transparent and leaves the surface of the leather step through.

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Claims (7)

P a ten t claims 1. Azo dyes of the general formula XR ^R i ^H0 I / \> _ c ---- NC - \ . 'v-OH (I) ZR ₂ \ R ₃ in which both X are identical and denote hydrogen atoms or hydroxyl groups, R, and R can be identical or different and denote a hydrogen atom or a hydroxyl group, an alkyl or aryl group, R ₃ denotes a hydrogen atom or an alkyl or aryl group, Z denotes a hydrogen atom or is any substituent, η is 0 or 1 and A is the radical of a diazotizable primary aromatic amine A-NH ₂ which contains at least one sulfonic or carboxylic acid radical. 2. Colorants obtained by nitrosation of the colorants according to claim 1. 3. Dyes obtained by oxidation of the dyes according to Claims 1 and 2. 209815 / 167G 2U9513 4. Metal-containing complexes of the dyestuffs according to Claim 1, in which the radical A is in the ortho position to the azo bridge carries a complex-forming radical, and the dyestuff according to claim 2. 5. Organosoluble dyes obtained by salt formation of a dye according to claims 1-4 with an amine or a quaternary ammonium salt. 6. Couplers of the general formula X R, OH -OH and No. ¹ X R, H = ⁷ ! ^Λ 2 ^Λ 3 ^Λ 2 in which Z ¹ denotes any substituent, X, Z, R ₁ , R ₂ and R _{3 have} the same meanings as in claim 1. 7. A method for dyeing leathers of various tannings, characterized in that it consists in that on this the dyes defined under 1, their oxidized, nitrosated or metal-containing derivatives - 30 209815 / 1B7G or the organosoluble salts of said dyes or their derivatives are applied. 209815/1676