EP0045457B1 - Continuous or semi-continuous process for dyeing knitting goods from circular knitting machines, and containing cellulosic fibres, with azoic developing dyes - Google Patents

Description

The invention explained below relates to the uniform dyeing of tubular chair knitted fabrics made of cellulose fibers, in particular cotton, with water-insoluble azo dyes produced on the fiber according to a continuous or semi-continuous method, the priming by pre-padding with a coupling component under alkaline conditions and the subsequent dye -Development wet-on-wet by padding with a diazo component in the presence of acid or acid-providing substances.

The dyeing of cotton fabrics with azo developing dyes on the foulard is well known. Normally, after priming with the coupling component, the textile material is then dried and then the dye is formed on the fiber by padding the pre-padded goods with the coupling-capable diazo component. When using voluminous textiles, however, this known method cannot be carried out because migration problems which are noticeable in the intermediate drying of the wet primer from the first stage cannot be solved. In principle, however, it would be possible to dispense with such intermediate drying at all and to pad wet-on-wet dyeing material with the diazo component. However, such a project could only be implemented in exceptional cases. In practice, however, attempts based on this working principle have failed because it has so far not been possible to dissolve the necessary amounts of diazo component in the additional amount of liquor absorbed from the (from priming) wet goods during the second padding, i.e. when padding with the development fleet, the fleet intake is insufficient under the given circumstances.

Also known for the production of azo dyes on the fiber is an application technique in which, in addition to the coupling component, a stabilized but non-coupling-capable diazo component is simultaneously applied to the textile material as part of the priming block. After this, wet-in-wet overlapping with acid causes the release of the diazonium compound together with the dye coupling. However, this process can only be carried out on non-voluminous, smooth textile webs, because in the case of voluminous textiles, the neutralization of the alkaline primer inside the product is faster than the formation of the coupling-capable diazonium compound, which ultimately results in the image of poor coloration due to uneven dye coupling between the outside of the product and the inside of the product results.

When dyeing tubular knitted fabrics in tubular form, the above-mentioned difficulties occur to an increased extent. Here too, not enough liquor can be applied to the goods during the second padding, or the solubility of the diazonium compounds is not sufficient to be able to dissolve enough of them in the additional liquor absorbed by the textile material.

On the other hand, with such a procedure, the concentration of the alkali binders to set the favorable coupling pH range becomes so high that local "over-neutralization" takes place the first time the primed, alkaline goods come into contact with the development liquor, and this slows down due to the higher product density running dye coupling additionally disturbs.

The object of the present invention was therefore to eliminate the disadvantages described above in the two-bath dyeing of round chair knitted fabrics in tubular form, wet-on-wet with the components for forming azo dyes on the fiber. The primary problem here was the means by which or in which way a higher liquor absorption by the textile material can be achieved in the second padding with the diazo component or only with acid.

This object is achieved according to the invention by adding 10 to 30 g / l of a polymer or copolymer of acrylic acid amide in the form of a 2 to 8, preferably 4 to 5% by weight, aqueous setting and 2 to 20 g of the alkaline primer liquor with the coupling component / I of an anionic wetting agent, and the acidic development liquor with the couplable diazo component likewise 30 to 60 g / I of a polymer or copolymer of acrylic acid amide in the form of a 2 to 8, preferably 4 to 5% by weight, aqueous setting and 2 to 20 g / I of the anionic or nonionic wetting agent is added.

• a) lineare oder verzweigte Polymerisate des Acrylsäureamids;
• b) Mischpolymerisate aus Acrylsäureamid und Halbestern der Maleinsäure mit Polyglykoläthern von natürlichen oder synthetischen Fettalkoholen (mit 12 bis 18 C-Atomen) mit 5 bis 10 Mol Äthylenoxid je Mol Fettalkohol, im Gewichtsverhältnis von 1:0,05 bis 1:0,5 (bezogen auf das Acrylsäureamid);
• c) Mischpolymerisate aus Acrylsäureamid und Acrylamidopropansulfonsäure im Gewichtsverhältnis von 1:0,05 bis 1:0,5 (bezogen auf das Acrylsäureamid);
• d) Mischpolymerisate aus Acrylsäureamid und N-Vinyl-N-methylacetamid im Gewichtsverhältnis von 1:0,05 bis 1:0,5 (bezogen auf das Acrylsäureamid);
• e) Mischungen der vorstehend unter a) bis d) genannten Polymerisate untereinander und gegebenenfalls in Kombination mit s-Caprolactam im Gewichtsverhältnis von 1:0,5 bis 1:1 (bezogen auf die Polymerisate).

Examples of such polymers or copolymers of acrylic acid amide are:

• a) linear or branched polymers of acrylic acid amide;
• b) copolymers of acrylic acid amide and half-esters of maleic acid with polyglycol ethers of natural or synthetic fatty alcohols (with 12 to 18 carbon atoms) with 5 to 10 moles of ethylene oxide per mole of fatty alcohol, in a weight ratio of 1: 0.05 to 1: 0.5 ( based on the acrylic acid amide);
• c) copolymers of acrylic acid amide and acrylamidopropanesulfonic acid in a weight ratio of 1: 0.05 to 1: 0.5 (based on the acrylic acid amide);
• d) copolymers of acrylic acid amide and N-vinyl-N-methylacetamide in a weight ratio of 1: 0.05 to 1: 0.5 (based on the acrylic acid amide);
• e) Mixtures of the polymers mentioned above under a) to d) with one another and, if appropriate, in combination with s-caprolactam in a weight ratio of 1: 0.5 to 1: 1 (based on the polymers).

The polymers used The acrylic acid amide or its copolymers with the other monomers mentioned above under a) to e) have a molecular weight of 1.0-10 ⁶ to 2.5-10 ⁶ , preferably 1.5 × 106 to 2.0. 106 on.

The specific properties of the acrylic acid amide polymers mentioned surprisingly result in an increase in liquor absorption at the same roller pressure (in bar / cm ² ). This effect is roughly proportional to the amount of products used, ie the higher the application concentration, the greater the increase in liquor intake within a technically justifiable range (in line with the recommended concentrations of the added polymers).

Through the participation of polymers or copolymers of acrylic acid amide and a wetting agent in the context of the present invention, it is possible to increase the liquor uptake by the material to be dyed both in the primer and in the wet-on-wet padding with the developing liquor and to penetrate them through to promote the double-lying textile material in such a way that level, well-colored goods hoses are obtained.

In contrast to the dyeing results, omitting the combination of auxiliaries used according to the invention, surprisingly, according to the new working principle, depending on the setting and performance of the foulard used, padding with the priming liquor results in a liquor absorption of 70 to 120% (on the weight of the dry goods) ) and - which only enables the claimed process - in the second padding with the development fleet, fleet intake values of an additional 90 to 130% by weight, ie in the end, a total liquor absorption of 180 to 250 wt .-% with two padding. This is the only way to dissolve the necessary amount of diazo component in this additional amount of liquor. In addition, the alkali binder concentration is brought to normal values in this way, so that this no longer affects the coupling conditions. The wetting agent in turn causes a rapid, uniform penetration of the fabric hose with both padding liquors and thus contributes to the good and, above all, uniform coloring of the same.

The increased absorption of the liquor also means that irregularities which the textile material exhibits immediately after leaving the foulard are compensated for by diffusion, so that there is no marking of the squeezed edges of the knitted tube. Another deficiency that has occurred in previous attempts is also eliminated.

The use of the padding aids according to the method according to the invention makes it possible for the first time to dye even bulky tubular material with the components for forming water-insoluble azo dyes on the fiber perfectly and without intermediate drying. This means technical progress, because until now it was only possible to apply developing dyes in a wet-on-wet process on smooth and thin goods. In addition to the fact that the new process offers no advantage on this type of smooth product, it is surprising that the higher liquor uptake which is the basis of the invention cannot be achieved there either by adding the acrylic acid amide polymers and the wetting agent.

Now, with continuous dyeing, the use of acrylic acid amide polymers or corresponding mixed polymers in the padding liquors is no longer new. Thus, use is made of this in the process according to DE-A-28 15 511, which, taking into account the fixing conditions, amounts to suppressing the migration of disperse dyes to polyester / cellulose blended fabrics in the course of the intermediate drying and thus the occurrence of gray haze during thermal insulation. In the case of DE-A1-27 38 497, the aid is also used to prevent migration during intermediate drying. In these known techniques, the action of the acrylic polymers is based on counteracting the migration of the liquor or of the dye or finishing agent contained therein during intermediate drying. However, this finding cannot be interpreted in the direction of the present invention idea, where the opposite behavior of the polymer additive is decisive for the compensation of the liquor distribution.

Of the textile materials, round chair knitted fabrics made of cellulose fibers, in particular cotton, are suitable for the method according to the invention, which are used in tubular form, in which levelness is particularly important. As such knitted fabrics, even stool-raw goods (advantageous for very full or covered shades) can be used. The claimed method can of course also be carried out with sliced goods.

For the dyeing of the textiles according to the present invention, the chemical compounds listed in the Color Index, 3rd edition 1971, which are customary for the production of development dyes, are suitable as "Azoic Coupling Component" and "Azoic Diazo Component".

Some of the polymerization products of acrylic acid amide used according to the invention are known (DE-A-2 542 051, CASSELLA AKTIENGESELLSCHAFT), but they are used for a completely different purpose, namely to suppress the “frosting effect” when dyeing polyester fibers with disperse dyes.

• Zuerst wird das schlauchförmige Textilgut für die Klotzbehandlung breitgelegt. Die erste Klotzung zur Grundierung erfolgt üblicherweise auf dem Foulard mit einer alkalischen Lösung einer Kupplungskomponente unter Zusatz der erfindungsgemässen Kombination aus polymerisiertem Acrylsäureamid und Netzmittel in den vorgeschriebenen Mengenverhältnissen. Dabei erhält man in der Regel Flottenaufnahmewerte zwischen 70 und 120 Gew.-%. Nach einem Luftgang (kontinuierlich) oder einer zwischengeschobenen kurzen Verweilzeit (halbkontinuierlich) wird dann die so hergestellte Grundierung nass-in-nass in Gegenwart von Alkalibindemittel (Säure oder säureliefernde Substanzen) mit der eine kupplungsfähige Diazokomponente enthaltenden Entwicklungsflotte überklotzt, wobei man dieser zweiten Klotzflotte ebenfalls die erfindungsgemässe Kombination aus polymerisiertem Acrylsäureamid und Netzmittel in den angegebenen Mengen zusetzt.

The new procedure is carried out as follows:

• First, the tubular textile material for block treatment is laid out. The first block for priming is usually done the foulard with an alkaline solution of a coupling component with the addition of the combination of polymerized acrylic acid amide and wetting agent according to the invention in the prescribed proportions. Fleet absorption values of between 70 and 120% by weight are generally obtained. After an air passage (continuous) or an interposed short dwell time (semi-continuous), the primer thus produced is then wet-on-wet in the presence of alkali binders (acid or acid-providing substances) with the development liquor containing a coupling-capable diazo component, with this second pad liquor likewise being padded the combination of polymerized acrylic acid amide and wetting agent according to the invention is added in the stated amounts.

A modification of the claimed process is provided by the following procedure, the textile material in the first padding process consisting of alkaline liquor, which at the same time forms the coupling component together with a non-coupling-capable diazo component, either in the form of a diazonium compound which is not coupling-capable under the above conditions or in the form of a suitably prepared (finely dispersed or dissolved in organic solvents), diazotizable amine with the sodium nitrite necessary for diazotization, in addition to the mixture of auxiliaries according to the invention, is pre-padded for priming, after which only the acid which triggers the coupling or the diazotization and coupling is added in the second padding process applies to the goods together with the polyacrylic acid amide / wetting agent combination. This modified method can be further modified by applying the coupling component and sodium nitrite together with the auxiliary mixture in the first padding process and then in the second phase padding over a diazotizable amine, acid and the auxiliary mixture to develop the dye.

The following examples are not intended to represent any restriction, especially as far as the wetting agents used are concerned, but merely to explain the present invention. The percentages evident in the exemplary embodiments mean percentages by weight; in the case of wet treatment of textiles, such percentages with regard to liquor absorption relate to the weight of the dry goods.

example 1

300 kg of raw interlock tubing made from cotton are to be dyed semi-continuously. To do this, block the goods on the padder with a padding liquor of 20 ° C, containing an aqueous solution of:

At the first padding you get a 100% liquor absorption of the textile goods. Then you roll up the treated goods and let them linger for 1 hour while slowly rotating the chews. To develop the dye, the primer is padded wet-on-wet at 20 ° C. using an aqueous liquor containing:

This results in a 100% liquor absorption on the tubular knitted fabric, so the total liquor absorption is 200%. The dye formation is then completed in an air passage of 30 seconds and a hot water passage at 80 ° C. Then the color is soaped and dried as usual.

You get a uniform, completely dyed through hose in Bordo.

If the dyeing described above was carried out analogously, but without the addition of acrylic acid amide polymer and wetting agent, liquor pickups of 90% were obtained on the first padding and only 20% on the second padding, and an uneven, partially not completely colored, i.e. still white in places, goods hose. Increasing the concentration of the diazonium compound to 270 g / l, as would be necessary with an additional liquor uptake of only 20%, fails because of the insufficient solubility thereof.

Example 2

150 kg of raw interlock tubular goods made of cotton are to be dyed. To do this, block the textile material on the foulard with an aqueous padding liquor of 20 ° C from:

In this way, a liquor absorption of 120% is obtained on the textile goods. After 3 minutes of air passage, the primer thus prepared is padded wet-on-wet on the foulard with an aqueous liquor at 80 ° C. containing: ..

This results in an additional liquor absorption of 120% on the tubular knitted fabric. An air passage of 45 seconds duration and a hot water passage at 80 ° C then complete the dye coupling.

After the aftertreatment, which is carried out in the usual way, an irrelevant and well-colored tube is obtained in a brilliant scarlet.

Example 3

Cotton interlock goods should be bleached and dyed at the same time. To do this, block the fabric hose on the foulard with a liquor absorption of 100% with an aqueous pad liquor at 20 ° C containing:

After padding, the primer prepared in this way is rolled up for 1 hour and then padded with an aqueous liquor at 80 ° C., which contains the following additives, without intermediate drying on the padder

The goods are then rolled up again and held for 3 hours at 85 ° C. for dye coupling. The additional liquor absorption in the second padding is 100%, so that the goods hose now contains 200% moisture.

After the residence time, the dyeing is rinsed and post-treated as usual. A shell-free, brilliantly red-colored goods tube is obtained; Color and levelness are flawless.

The second stage of the treatment of the fabric tube can also be carried out continuously with a similar result by steaming for 3 minutes at 103 ° C. instead of the three-hour dwell to complete the dye development.

Example 4

aufweist, kalt (20 °C) bei einer Flottenaufnahme von 120% geklotzt und diese Grundierung wird sodann für 1 Stunde aufgerollt. Die Farbstoffbildung wird nun durch Überklotzen des nassen Warenschlauches auf dem Foulard mit einer wässrigen Flotte enthaltend:

bei 20 °C und einer zusätzlichen Flottenaufnahme von 100% (die Gesamtflottenaufnahme beträgt also 220%) eingeleitet und durch einen Luftgang von 20 Sekunden Dauer sowie eine Heisswasserpassage bei 80 °C vervollständigt.250 kg of raw cotton interlock fabric in the form of a tube are to be dyed. To do this, the textile material is placed on the padder with a liquor that contains an aqueous solution of:

has, cold (20 ° C) padded with a liquor absorption of 120% and this primer is then rolled up for 1 hour. The dye formation is now obtained by padding the wet fabric hose on the foulard with an aqueous liquor:

at 20 ° C and an additional liquor intake of 100% (the total liquor intake is therefore 220%) and completed by an air passage of 20 seconds and a hot water passage at 80 ° C.

After the aftertreatment of the dyeing, which is carried out as usual, a perfectly dyed goods tube is obtained in a level, brilliant red shade.

Example 5

rollt die so hergestellte Grundierung auf und lässt diese 1 Stunde bei Raumtemperatur verweilen. Danach wird die Ware auf dem Foulard bei 20 °C und einer zusätzlichen Flottenaufnahme von 110% nass-in-nass überklotzt unter Verwendung einer wässrigen Entwicklungsflotte, die im Liter Wasser enthält:

For dyeing 60 kg of interlock raw material in tubular form made of cotton, the textile material is padded on the foulard at 20 ° C. and a liquor absorption of 90% with a pad liquor containing an aqueous solution of:

rolls up the primer prepared in this way and lets it linger for 1 hour at room temperature. The goods are then padded on the padder at 20 ° C and an additional liquor absorption of 110% wet-on-wet using an aqueous development liquor which contains in liters of water:

The dye formation is then completed by an air passage lasting 60 seconds and a hot water passage at 80 ° C. After the usual post-treatment of the dyeing, a dull red interlock tube of any color is obtained with good coloration.

Example 6

Continuous dyeing of raw cotton interlock fabric in tube form. In this case, the block liquor for priming contains as an aqueous solution:

So you block the fabric hose on the foulard at 20 ° C and a liquor absorption of 120%, place the textile goods treated in this way for 3 minutes in a chute and block them with an aqueous development liquor without intermediate drying and without interrupting the flow of goods on a second foulard:

The liquor absorption of the hose in this second block is 90%. Now there is an air passage of 40 seconds and a hot water passage at 80 ° C to complete the dye coupling.

This dyeing is then aftertreated, as is usual with dyeings with development dyes. In this way, a brilliant orange-colored product hose is obtained; Equality and color are good.

If, however, the wetting agent and the acrylic acid amide polymer are omitted when carrying out the dyeing operation described above in the primer and development liquor, a liquor absorption of 120% can also be obtained with appropriate setting of the padding pad in the primer. However, it is then impossible to achieve an additional fleet intake with the second padding. In this case, the development liquor is almost no longer penetrated into the goods hose and an unegal orange shade is obtained, with no coloring at all inside the hose.

Claims (11)

1. A process for the even dyeing of a tubular knitted fabric in hose form and consisting of or containing cellulose fibers, with water-insoluble azo dyestuffs produced on the fiber according to a continuous or semi-continuous method, in which the impregnation is performed by pre- padding the hose fabric with a coupling component under alkaline conditions, and subsequently the development of the dyestuff is effected, wet- in-wet, by slop-padding the textile goods with a diazo component in the presence of an acid and/ or an acid-forming substance, which comprises adding to the alkaline impregnation bath containing the coupling component an auxiliaries' combination of polymers or copolymers of acrylic acid amide, said polymeric component being incorporated in an amount of from 10 to 30 g/I in the form of a 2 to 8% (by weight), preferably 4 to 5% (by weight), aqueous formulation, and of from 2 to 20 g/I of an anionic wetting agent; and likewise adding to the acidic developing liquor containing the diazo component capable of being coupled an auxiliaries' combination of polymers or copolymers of acrylic acide amide, said polymeric component being incorporated in an amount of from 30 to 60 g/I in the form of a 2 to 8% (by weight), preferably 4 to 5% (by weight), aqueous formulation, and of from 2 to 20 g/I of an anionic or nonionic wetting agent.

2. A process as claimed in claim 1, wherein as polymeric component linear or branched homopolymers of acrylic acid amide are added.

3. A process as claimed in claim 1, wherein as polymeric component copolymers of acrylic acid amide and semiesters of maleic acid with polyglycol ethers of natural or synthetic fatty alcohols (of from 12 to 18 carbon atoms) with from 5 to 10 mols of ethylene oxide per mol of fatty alcohol, in a weight ratio of from 1:0.05 to 1:0.5 (calculated on the acrylic acid amide) are added.

4. A process as claimed in claim 1, wherein as polymeric component copolymers of acrylic acid amide and acrylamido-propane-sulfonic acid in a weight ratio of from 1:0.05 to 1:0.5 (calculated on the acrylic acid amide) are added.

5. A process as claimed in claim 1, wherein as polymeric component copolymers of acrylic acid amide and N-vinyl-N-methyl-acetamide in a weight ratio of from 1:0.05 to 1:0.5 (calculated on the acrylic acid amide) are added.

6. A process as claimed in claims 2 to 5, wherein mixtures of the specified polymeric components one with another are added.

7. A process as claimed in claims 2 to 6, wherein to the specified polymeric components s-caprolactam is further added in a weight ratio of from 1:0.5 to 1:1 (calculated on the weight of the polymeric component).

8. A process as claimed in claims 1 to 7, wherein the applied polymers of acrylic acid amide or the copolymers thereof have a molecular weight of from 1.0 .106 to 2.5 1 Os.

9. A modification of the process as claimed in claims 1 to 8, wherein the alkaline impregnation bath contains, in addition to the auxiliaries' combination, the coupling component and a diazonium compound not capable of being coupled of a diazotizable amine; and the acidic developing liquor contains, in addition to the auxiliaries' combination, substantially only acid.

10. A modification of the process as claimed in claims 1 to 8, wherein the alkaline impregnation bath contains, in addition to the auxiliaries' combination, the coupling component, a diazotizable amine and sodium nitrite; and the acidic developing liquor contains, in addition to the auxiliaries' combination, substantially only acid.

11. A modification of the process as claimed in claims 1 to 8, wherein the alkaline impegnation bath contains, in addition to the auxiliaries' combination, the coupling component and sodium nitrite; and the acidic developing liquor contains, in addition to the auxiliaries' combination, a diazotizable amine and acid.