EP0244706A2 - Process for dyeing mixtures of polyamide and cotton - Google Patents

Abstract

In the dyeing of polyamide-cotton mixtures with azoic dyes only it is important to have dye-forming components which exhaust conjointly on at least one of the two fibres. Another prerequisite is that the coupling and diazo components in question remain stable side by side in the same exhaust bath under the conditions of the first impregnation without precipitation of azo dyes already formed in this liquor as a result of coupling or any other separation, which would have an adverse effect on the fastness of the dyeings to be produced only on the fibre. The lately available liquid preparations of specially dispersed aromatic amines, then, are diazo component precursors which meet the requirements mentioned, so that the two different constituent fibres of the blend can be coloured, admittedly in succession, but with one and the same class of dye. In addition, owing to the separate dyeing of the two fibre portions, it is possible, by varying the amines used as diazo components, to obtain bicolour effects.

Description

The present invention relates to a new process for dyeing textile mixtures of synthetic polyamide fibers and cellulose fibers, especially cotton, by drawing out from an aqueous medium with water-insoluble azo dyes produced from the coupling component and diazo component on the fiber.

In textile practice, there has long been interest in blends of polyamide fibers and cotton, due to the composition of which the components are usually in a ratio of 40:60 to 60:40 (but other mixing ratios are also known), genuine and simple Way of coloring.

Textile articles made from such blends have become particularly important in the sportswear sector, with fashion preferring garments in contrasting colors, which are then intended to withstand intensive washing without the colored parts mutually bleeding into one another or colored parts bleeding into white. The latter problem in particular has so far only been inadequately solved and naturally requires very cumbersome, expensive dyeing processes.

• Dazu behandelt man die Fasermischung bei erhöhter Temperatur (60°C) zunächst mit alkalischen Bädern, die gemeinsam eine gelöste Kupplungskomponente (Naphtholat) sowie eine dispergierte, nicht kupplungsfähige Diazokomponente (Ofna-perl Salz) enthalten. Nach dieser Grundierungsphase wird der hierbei auf die Cellulosefaser aufgezogene Anteil der Kupplungskomponente durch die Einwirkung einer dem Färbevorgang frisch zugeführten, umsetzungsfähigen Diazoniumverbindung einer Echtbase zum Farbstoff entwickelt und erst dann wird die bisher von sich aus nicht kupplungsfähige Diazokomponente, welche im Verlauf der Vorgrundierung zugleich auf die Polyamidfaser gezogen war, durch eine einfache Säurebehandlung des Textilgutes kupplungsfähig gemacht und somit (in der PA-Faser) ebenfalls zum Azofarbstoff gekuppelt. Im Anschluß an diese Maßnahmen sind beide Faserarten in der gewünschten Nuance eingefärbt. Das bewährte Verfahren steht der Praxis jedoch nicht weiterhin zu Verfügung, weil sich keine solchen stabilisierten, nicht kupplungsfähigen Diazoniumverbindungen mehr im Handel befinden.

In this regard, as a state of the art a leaflet Hoe 2277 "Ofna-perl Salt RAA" and Hoe 2314 "Ofna-perl Salt BBA" from Farbwerke Hoechst AG from 1953 and 1954 show a generic process for mixed textiles made of synthetic materials Polyamide fibers and cellulose fibers can be dyed as follows:

• To do this, the fiber mixture is first treated at an elevated temperature (60 ° C.) with alkaline baths, which together contain a dissolved coupling component (naphtholate) and one contain dispersed, non-couplable diazo component (Ofna-perl salt). After this priming phase, the portion of the coupling component drawn onto the cellulose fiber is developed into the dye by the action of a diazonium compound of a real base which is freshly supplied to the dyeing process and only then is the diazo component which has so far not been able to be coupled, which, during the course of the pre-priming, simultaneously applied to the Polyamide fiber was drawn, made couplable by a simple acid treatment of the textile material and thus (in the PA fiber) also coupled to the azo dye. Following these measures, both types of fiber are dyed in the desired shade. However, the proven method is no longer available in practice because there are no longer any stabilized, non-coupling-capable diazonium compounds on the market.

Another known process in the field in question uses a mixture of coupling component and aromatic amine for dyeing synthetic fiber materials, preferably PES fibers, both of which are primed under HT conditions on the fabric and then diazotized at a higher temperature (70 ° C.) In the case of fiber blends, however, only the synthetic fiber is dyed according to this method, however a simultaneous coloring of the cellulose fiber is not possible.

Accordingly, it is an object of the present invention to provide a replacement for the dyeing technique with azo developing dyes known from the aforementioned information documents, which allows dyeings to be made on polyamide fiber / cellulose fiber mixtures without the need for complex process steps which meet the high authenticity requirements, as described above. The object is achieved according to the invention by treating the textile material at elevated temperature in alkaline baths which contain at least one dissolved coupling component and the dispersion of at least one specially prepared aromatic amine (real dye base), then - optionally with or without intermediate rinsing - develops the portion of the coupling component previously drawn onto the cellulose fiber by reaction with a couplable diazo component (dye salt or diazot. amine) freshly introduced into the dyeing process there, then the aromatic amine originating from the primer and drawn onto the polyamide fiber by diazotizing in transferred a coupling-capable diazonium compound and developed there with the portion of the coupling component which is at the same time on the polyamide fiber to form a dye and finally the dyeing thus created on the two constituents of the fiber mixture as usual usually treated.

A dyeing process on the basis of the invention has not yet been possible because it has only recently been possible to bring the amine required for this into a sufficiently finely divided form which is stable under the alkaline conditions to be used and which is suitable for the actual dyeing.

Only the breakthrough in the course of the procedures for the preparation of aromatic amines (liquid preparations of dispersed bases), such as those e.g. described in the German patents DE-C-23 14 938, 25 52 711 and 26 40 138 and in the German patent application DE-A-29 09 639 has opened up the possibility of considering such a dyeing method for the fiber mixtures mentioned , although it was by no means certain whether the way in which the amines were prepared would not affect their pulling ability on the polyamide fiber or at least considerably interfere with it.

It is known to the person skilled in the art that the anionic and / or nonionic auxiliaries used for the preparation of the aromatic amines in question have a strong retarding effect, especially in the case of synthetic polyamide, when dyeing synthetic fibers. It was therefore surprising that the aromatic amines dispersed in this way nevertheless display a high drawability with respect to the polyamide fiber under the dyeing conditions explained.

As a remarkable advantage of the invention compared to the conventional coloring methods for the fiber mixtures considered here, it should be emphasized that instead of two separate dyeing processes so far, together with the use of two different dye classes, in which one of the dyeings obtained in this way often did not meet the expected authenticity requirements, now only a dye class is used and high authenticity requirements can be met.

In the course of carrying out the new process, there is also the choice of using the diazonium compound of a different shade of aromatic amine than the one used for dyeing the polyamide fiber component in the production of the dye on the cellulose fiber portion of the fiber mixture, and one wins so simple two-color effects. In addition, it is still possible to vary between the use of ready-to-use, stabilized diazonium compounds, the so-called true-color salts, or the use of aromatic amines which have been converted into the corresponding diazonium compound by diazotization. In all cases, it is possible according to the invention to obtain real and tone-on-tone colored or, if desired, also bicolor-colored mixed textiles.

Of course, the claimed method can also be used solely for dyeing the polyamide fiber content of mixed textiles. For this purpose, the goods are primed - at high temperature - with coupling component and amine and after the intermediate rinsing, without the addition of table salt, only the amine applied to the fiber is simply diazotized, whereupon the resulting dye development with the coupling component also present there Coloring (only of the PA portion) then further treated as usual.

The chemical compounds used to produce azo development dyes by the process according to the invention are listed in the COLOR INDEX, 3rd edition 1971 together with additions in 1975 under the term "Azoic Coupling Component" and as "Azoic Diazo Component".

The measures for priming the fiber mixtures are generally carried out at temperatures between 50 'and 80 ° C according to the novel dyeing method, but this treatment process is also initially carried out at temperatures in the range from 50 ^* to 80 ° C and then the temperature of the pull-out bath to values can drop to 30'C. The subsequent intermediate rinsing of the primed goods is expediently carried out in the cold under alkaline conditions. Sodium nitrite and mineral acids are usually used to diazotize the amine drawn onto the polyamide fiber portion of the goods and this step is generally carried out at temperatures up to 50 ° C.

The following examples serve to explain the claimed dyeing methods and also show process variants, but they are in no way intended to limit the inventive concept. The percentages given here are percentages by weight.

example 1

• 1,5 ml/l Natronlauge (32,5 %ig) sowie
• 1,5 g/1 eines anionischen Schutzkolloids auf Basis eines Fettsäure-Eiweißhydrolysat-Kondensationsproduktes.

For dyeing a mixed fabric made of 40% polyamide 66 fiber (nylon) and 60% cotton by pulling out at a liquor ratio of 1:20, a bath is made up from 70 ° C warm, soft water and loaded with

• 1.5 ml / l sodium hydroxide solution (32.5%) and
• 1.5 g / 1 of an anionic protective colloid based on a fatty acid-protein hydrolyzate condensation product.

• 1,5 g/1 einer handelsüblichen, flüssigen Aufbereitung von Azoic Diazo Component 46 mit der C.I.-Nr. 37080 (Echtscharlach TR Base) als nicht-diazotiertes Amin,
• 1,5 g/l des obengenannten anionischen Schutzkolloids, 3 ml/l Spiritus (Ethanol denat.) und
• 4,5 ml/l Natronlauge (32,5 fig) in ca. der 5-fachen Menge Wasser bei 70°C dispergiert, sowie ebenfalls bei 70°C eine wäßrige Lösung hergestellt (ohne Zusatz von Formaldehyd) aus
• 5 g/l einer handelsüblichen, flüssigen Einstellung von Azoic Coupling Component 8 mit der C.I.-Nr. 37525, verdünnt mit
• 5 ml/l Spritus (Ethanol denat.).

In the meantime, each has prepared two product batches with the following composition (based on the liquor ratio 1:20), which are stirred into the alkaline bath in the order given:

• 1.5 g / 1 of a commercially available, liquid preparation of Azoic Diazo Component 46 with the CI no. 37080 (Echtscharlach TR Base) as non-diazotized amine,
• 1.5 g / l of the above-mentioned anionic protective colloid, 3 ml / l of alcohol (ethanol denat.) And
• 4.5 ml / l sodium hydroxide solution (32.5 fig) dispersed in about 5 times the amount of water at 70 ° C, and also at 70 ° C prepared an aqueous solution (without the addition of formaldehyde)
• 5 g / l of a commercial, liquid formulation of Azoic Coupling Component 8 with the CI no. 37525, diluted with
• 5 ml / l spritus (ethanol denat.).

In this priming liquor prepared in this way, the textile material is now treated for 30 minutes at 70 ° C After 10 minutes of treatment, 10 g / l table salt is added to the bath in several portions. Thereafter, the goods are left to act on the priming liquor for a further 30 minutes while the bath is cooling, and another 10 g / l of sodium chloride are added as soon as the bath temperature has dropped below 50 ° C.

To ensure good fastness to rubbing of the dye to be developed subsequently, the mixed fabric primed in this way is now rinsed for 15 minutes in an aqueous medium, cold (20 ° C.) and with the participation of 20 g / l sodium chloride and 1 ml / l sodium hydroxide solution (32.5%) .

• 1,5 g/l von nach herkömmlicher Vorschrift diazotierter Azoic Diazo Component 46 mit der C.I.-Nr. 37080 (Echtscharlach TR Base),
• 10 g/l Natriumacetat und
• 0,3 ml/l Essigsäure (80 %ig)

während 30 Minuten vorgenommen.The development of the color on the cotton portion of the goods is then treated by treating them in an aqueous bath (first development liquor) at 20 ° C.

• 1.5 g / l of Azoic Diazo Component 46 diazotized according to conventional instructions with the CI no. 37080 (Echtscharlach TR Base),
• 10 g / l sodium acetate and
• 0.3 ml / l acetic acid (80%)

made during 30 minutes.

Now the dyeing from the first stage is rinsed thoroughly with water and the same is then used to produce the color on the polyamide fiber component of the goods in an aqueous bath (second development liquor) at 20 ° C starting from the action of 2 g / 1 sodium nitrite and 3 ml / l subjected to sulfuric acid (96%), increasing the temperature to 40 ° C and finally the diazotization of the during the priming phase brings up the amine and the coupling in this position over the course of 20 minutes at the set temperature.

• a) für 10 Minuten bei 60°C im wäßrigen Medium mit 25 ml/l eines lösungsmittelhaltigen Nachbehandlungsmittels auf Basis eines Alkarylpolyglykolether-Gemisches, 2 g/1 Soda kalz. und 2 g/l eines komplexbildenden Polyphosphats. sowie dann noch
• b) nach warmem Spülen (bei 80°C) für 10 Minuten bei 95°C im wäßrigen Medium mit 0,5 g/1 eines Dispergiermittels auf Basis von mit 22 Mol Ethylenoxid oxethyliertem Oleylalkohol, 1 g/l Soda kalz. und 1 g/l eines komplexbildenden Polyphosphats.

After thorough rinsing with water, the resulting color is finally soaped, first

• a) for 10 minutes at 60 ° C in an aqueous medium with 25 ml / l of a solvent-containing aftertreatment agent based on an alkaryl polyglycol ether mixture, 2 g / 1 soda salt. and 2 g / l of a complex-forming polyphosphate. as well as then
• b) after warm rinsing (at 80 ° C) for 10 minutes at 95 ° C in an aqueous medium with 0.5 g / 1 of a dispersant based on oleyl ethoxylated with 22 moles of ethylene oxide, 1 g / l of soda. and 1 g / l of a complex-forming polyphosphate.

The blended fabric results in a clear, real scarlet coloration of both the polyamide fiber and the cotton content of the goods.

If the tone-on-tone coverage of cotton fiber to polyamide fiber is not sufficient, after the primer bath has cooled, appropriate amounts of Azoic Coupling Component 8 can be added to it, which then only pull onto the cotton.

Example 2

To dye a polyamide fiber / cotton blend (ratio 60:40) in a fashionable two-tone effect, the textile material is first treated with the pull-out liquor having the two dye-forming components, as in Example 1. As soon as the temperature of the primer bath has dropped to approx. 30 ° C or has also been cooled, 3 g / 1 of Azoic Coupling Component 8 with the CI no. 37525 entered in the form of an aqueous solution and the goods are exposed to the liquor for a further 30 minutes under the changed conditions.

Instead of dye development with the diazonium compound from Azoic Diazo Component 46 with the C.I. 37080 (Echtscharlach TR Base), however, after completion of the priming phase, the coupling of the dye on the cotton portion of the fiber mixture by means of diazotized Azoic Diazo Component 51 with the C.I. 37195 (Real Navy Blue Salt RAS). This process is carried out here in the treatment of the pre-primed fabric in a (first) development liquor containing, as an aqueous solution, 6 g / l of a commercially available, stabilized diazonium compound from Azoic Diazo Component 51 with the C.I. 37195 in accordance with the regulation evident from example 1.

After the goods have been rinsed in the usual way, the process is carried out as in Example 1 to bring about the coloration on the polyamide fiber component (second development liquor).

A dyeing with navy blue-nuanced cotton content and red polyamide content is obtained on the fiber material, which have good fastness properties.

Example 3

If the dye formation from naphtholate and diazotized amine on the cotton (first process step) is omitted in the production of the dyeing according to the working instructions of Example 1, then only the polyamide fiber portion of the blended fabric is colored red.

Claims (5)

1. Process for dyeing textile mixtures of synthetic polyamide fibers and cellulose fibers by pulling them out of an aqueous medium with water-insoluble azo dyes produced from the coupling component and diazo component on the fiber, characterized in that the textile material is treated with alkaline baths at an elevated temperature for priming, at least one next to the other contain a dissolved coupling component and the dispersion of at least one specially prepared aromatic amine, then - optionally with or without intermediate rinsing - develop the portion of the coupling component previously drawn onto the cellulose fiber by reaction with a coupling-capable diazo component freshly introduced into the dyeing process there, then the dye Aromatic amine originating from the primer and drawn onto the polyamide fiber is converted into a coupling-capable diazonium compound by diazotization and also attached to the polyamide fiber The proportion of the coupling component developed there to the dye and the resulting color on the two components of the fiber mixture post-treated as usual. 2. The method according to claim 1, characterized in that the textile is treated for priming at temperatures between 50 ° and 80 ^* C with the dissolved coupling component and the specially prepared aromatic amine. 3. Process according to claims 1 and 2, characterized in that the textile material is first primed at temperatures between 50 'and 80 ^* C with treated the coupling component and the specially prepared aromatic amine and then the temperature of the bath can drop to values of up to 30 ° C. 4. Process according to claims 1 to 3, characterized in that the fabric is rinsed cold alkaline after treatment with the coupling component and the aromatic amine. 5. Process according to claims 1 to 5, characterized in that the aromatic amine applied to the textile by priming is diazotized at temperatures up to 50 ° C using sodium nitrite and mineral acids.