DE622753C - Process for dyeing leather - Google Patents

Description

Process for through-dyeing leather During further processing of the Group of azo dyes, which have the important property of leather, in particular Chrome leather to be dyed largely or completely, it has been found that aminoazobenzenesulfonic acids, the mono- or polyoxyalkyl-substituted amino groups in the coupling component and which can also be substituted in another way in the nucleus, with N-alkyl groups with more than two carbon atoms should be excluded also ideally suited for extensive dyeing of chrome leather. So far, N-oxalkylated acidic azo dyes have only been used for dyeing textile fibers been.

Yellow azo dyes used for dyeing leather, such as Orange II from diazotized I-aminobenzene-4-sulfonic acid and # -naphthol (S ch u l t z, Dye Tables, 6th Edition, No. I45) or Metanil yellow extra from diazotized I-aminobenzene-3-sulfonic acid and diphenylamine (Schultz, op. Cit., No. IX or der nitrated azo dye from diazotized I-aminobenzene-4-sulfonic acid and diphenylamine (Schultz, op. Cit., No. I4I), can only color chrome leather on the surface. In contrast, the new dyes penetrate deeply into the leather, mostly for the most part even color it all the way through. Leather dyed in this way, especially chrome leather, have great advantages. They have colored interfaces, and if injured the surface or wear and tear through use no longer shows the uncolored core revealed.

Dyes that penetrate deep into the dermis or chrome leather able to dye completely, have so far only become known in individual cases; z. B. yellow monoazo dyes made from diazotized 2-chloro-4-amino-I-methyl-6-sulfonic acid and resorcinol, whose substitution products and homologues are obtained, chrome leather completely through. By finding the oxalkyl-substituted aminoazobenzene dyes, which penetrate the interior of the leather without the addition of alkali and largely color it through, the technology is enriched significantly.

The dyes can be used according to the following coloring methods: Dyeing instructions The neutralized pelts are in a barrel with 150 to 200% water stained at 65 ° C. The keg is set in motion and the dye solution is then added through the hollow axis too. After 45 minutes, add the fat liquor and stir another 45 minutes. If the hides are very heavy, the dyeing time is to be extended accordingly. In general, z to 2% of the shaved weight is sufficient calculated dye in order to achieve strong colorations.

The dyes are prepared by the usual method, to its Explanation in the examples below and in the Tabel Production, composition and coloring properties of some representatives of these Group of dyes of the aminoazobenzot series are indicated without a want to give a complete list of all possible dyes.

Example I 173 parts by weight of 3-aminobenzene-I-sulfonic acid are, as customary, diazotized and at 0 to 3 ° C with 18I parts by weight of dioxäthylaminobenzene, which were previously dissolved with the necessary amount of hydrochloric acid in weak Congo acidic conditions, coupled. The reaction is kept weakly Congo acidic by adding sodium acetate solution. To The end of the dye formation is made weakly alkaline with soda and the mixture is heated up and salt out. The dye is a yellow, crystalline powder. He dyes leather in particular chrome leather, according to the above dyeing instructions, bright yellow through.

EXAMPLES I27.5 parts by weight of 2-chloro-I-aminobenzene are customary Acetic acid diazotization with 26I parts by weight of 3-dioxäthylaminobenzene-I-sulfonic acid coupled. After the dye formation has ended, the dye becomes alkaline with soda isolated by appearance. It forms a yellow powder, the surface and core of Chrome leather colors bright yellow. Example 3 I38 parts by weight of 4-nitro-1-aminobenzene are diazotized and with a solution of 225 parts by weight of 3-N-Äthyloxäthylaminobenzol-I-sulfonic acid united. The clutch is driven to an end using acetic acid. Then it becomes soda-alkaline and the dye precipitated with salt as a crystalline, dark powder. It colors chrome leather in even, strong brownish-red tones on both the Surface as in the core.

EXAMPLE 4 218 parts by weight of 5-nitro-2-aminobenzene-I-sulfonic acid are diazotized with the necessary amount of nitrite and hydrochloric acid and coupled with 21.5.5 parts by weight of 3-chloro-I-dioxäthylaminobenzene, a trace of Congo acidic solution. The reaction is always kept slightly acidic to the Congo by adding sodium acetate. After the formation of the dye has ended, it is made alkaline with soda and the dye is isolated as usual. It is obtained as a dark red powder that colors the surface of chrome leather in deep burgundy red and the core in dark red-violet tones. Dye leather dye Diazo component Azo component on the surface inside 2-chloro-I-aminobenzene 3-Dioxäthylaminobenzol- strong yellow strong yellow I-sulfonic acid 2, 5-dichloro-I-aminobenzene the same. Deep orange deep orange 3,4-dichloro-I-aminobenzene similarly strong orange-yellow strong orange-yellow 2-nitro-I-aminobenzene similar brownish orange strong brownish orange 3-Nitro-I-aminobenzene like prangy yellow orange-yellow 3-Nitro-I-aminobenzene 3-N-Ethyloxäthylamino- strong yellow strong yellow benzene-I-sulfonic acid 4-Nitro-I-aminobenzene 3-Dioxäthylaminobenzene pale claret red deep claret I-sulfonic acid 4-Nitro-I-aninobenzol 3 -N Äthyloxäthylaminö- strong brownish- strong brownish- benzene-I-sulfonic acid red red 4-chloro-z-nitro-I-amino- 3-dioxäthylaminobenzene- brown orange strong brown- benzene I-sulfonic acid orange 2,6-dichloro-4-nitro-I-amide like pale yellow brown orange brown nobenzol z, 4-Dinitro-i-aningbenzene like. - red violet deep red violet - 3-Nitro-4-amino-i-methyl - _ the same. ° reddish yellow strong reddish yellow - benzene - Dye leather dye Diazo component Azo component on the surface inside 4-Nitro-2-amino-I-meth- 3-Dioxäthylaminobenzol- brownish orange strong brownish- oxybenzene I-sulfonic acid orange 4 - nitro - 2 - amino - I - ox- like brownish orange brownish orange ethyloxybenzene 3-Nitro-4-amino-I-ethoxy like orange brown, strong orange brown benzene 6-nitro-3-amino-4-meth- like dark red-brown deep dark red-brown oxy-I-methylbenzene 3-aminobenzene-I-sulfone-dioxäthyläminobenzol pure yellow strong pure yellow acid the same. Di- (ß, y-dioxy) _- propyl- yellow yellow aminobenzene 4-aminobenzene-i-sulfone-Dioxäthylaminobenzol yellow bright yellow acid the same. Di - (ß, y - dioxy) - propyl- reddish yellow reddish yellow aminobenzene 4 - chlorine - 2 - aminobenzene- .3-Dioxäthylaminobenzol- reddish yellow reddish yellow i-sulfonic acid i-sulfonic acid ' 6 - chlorine - 3 - aminobenzene - di - (ß, y - dioxy) - propyl - strong reddish yellow strong reddish yellow i-sulfonic acid aminobenzene- _ 2, 5-dichloro-4-aminoben- 3-dioxäthylaminobenzol- pale brownish orange-brown zol-i-sulfonic acid i-sulfonic acid. orange 2, 5-dichloro-3-aminobes like brownish orange brownish orange zol-i-sulfonic acid 3 - nitro - 4 - aminobenzene- di- (ß, y - dioxy) - propyl- brown-orange strong brown-orange i-sulfonic acid aminobenzene 4 - Nitro - 2 - aminobenzene- 3-N-Ethyloxäthylamino- brownish yellow strong brownish- i-sulfonic acid benzene-i-sulfonic acid yellow Likewise. Oxäthylaminobenzol dull yellow brownish yellow the same. 3 - Oxäthylamino - i - brown-yellow, strong brown-orange ethylbenzene Likewise. 3-Dioxäthylamino-i-me- orange brown deep orange brown ethylbenzene the same. 4-chloro-2-dioxäthylami- brown yellow brown yellow no-i-methoxybenzene the same. 3-Dioxäthylamino-i-oxy- strong brownish- strong brownish- benzene yellow yellow 5 - Nitro - 2 - aminobenzene- 3-N-Ethyloxäthylamino- deep burgundy deep red purple i-sulfonic acid benzene-i-sulfonic acid the same. Oxäthylaminobenzol violet brown violet brown The same. Dioxäthylaminobenzol pure Bordeaux red, strong burgundy red the same. 3 - Oxäthylamino - i - me- burgundy red bordeaux red ethylbenzene Likewise. 3-Dioxäthylamino-i-me- burgundy red deep dark violet ethylbenzene Dye leather dye Diazo component Azo component on the surface inside g - nitro - 2 - aminobenzene- 3-di -. (ß; y-dioxy) -propyl- pale burgundy red 'burgundy red i-sulfonic acid amino-i-methylbenzene the same. 3 - chlorodioxäthylamino deep burgundy, dark red-violet benzene the same. 3-chlorodi- (ß, y-dioxy) - burgundy red deep burgundy red propylaminobenzene Likewise. 3-Oxäthylamino-4-meth- violet brown deep violet brown oxy-i-methylbenzene the same. 3-Dioxäthylamino- gray-brown gray q.-methoxy- i -methyl- benzene Likewise. 3-Di- (ß, y-dioxy) -propyl- red-brown red-brown amino-q-methoxy- i-methylbenzene. Likewise. 2-Dioxäthylamino-i, 4-di-yellow-brown brown-violet methylbenzene

Claims (1)

PATENT CLAIM Process for dyeing leather through, marked through the use of salts of aminoazobenzenesulfonic acids that are in the coupling component Contain mono- or polyoxalkylamino groups and also in a different way may be substituted in the nucleus, with N-alkyl groups having more than two carbon atoms should be excluded.