EP0189850A2 - Pad-dyeing process for wool - Google Patents

Abstract

1. A cold pad-batch process for dyeing wool with a reactive dye, which comprises padding the fiber material with an aqueous liquor containing the dissolved reactive dye at a pH between 9 and 13 and then, to fix the dye, batching this padded material in the moist state at temperatures of not more than 25 degrees C, preferably at room temperature, for 6 to 24 hours under the entrained strongly alkaline conditions.

Description

The present invention relates to a pad-cold retention process for dyeing wool with reactive dyes.

Cold retention dyeing processes for wool have long been known to the colorist. Here, the textile material is padded with acid, metal complex or reactive dyes from an acidic medium and generally stored at room temperature for a certain period of time for dye fixation. In addition to the dyes used for this, the padding liquors used usually contain high amounts (up to 300 g / 1) of urea. Under these conditions, reactive dyes, especially those of the vinyl sulfone type, only incompletely fix and result in reduced fastness properties.

In practice, there is always the requirement to be able to offer matching plain colors for printing with reactive dyes on wool and created with the same dyes, which can be realized in a non-complex manner. Apart from the simplified warehousing, the background for this may be mainly to be seen in the fact that in the case of Composb articles, both the printed and the uncolored part of the textile goods are in agreement with the evening color that is decisive for wool articles, which is otherwise the case when using different dye combinations for such a design project is not given. In addition, the adjustment of the shade of the coloring based on an existing printing recipe is far less difficult.

The above-mentioned situation thus led to the task of developing an inexpensive dyeing process that requires little mechanical effort, namely a pad-cold-residence process for dyeing wool with reactive dyes, which does not have the shortcomings or disadvantages of the prior art shown above .

This object is achieved in that the fiber material is padded with the aqueous reactive liquors having dissolved reactive dyes at a pH between 9 and 13 and then this padding for dye fixation in the moist state for 6 to 24 hours, generally 12 to 18 hours , at temperatures up to a maximum of 25 ° C, preferably in the range of room temperature, under the traditionally strongly alkaline conditions.

The following can be used as fixative alkali for the reactive dyes in the padding liquors according to the present invention: sodium hydroxide solution in amounts of 5 g / 1 to 60 g / 1, if appropriate together with up to 50 g / 1 sodium chloride or Glauber's salt, i.e. in amounts as known from the block-dwell process known for cotton, or mixtures of sodium hydroxide solution with water glass in a ratio of 1: 1 to 1:10 and in amounts of 5 g / 1 to 250 g / l.

Such a procedure in the alkaline medium, as practiced by the claimed process, was completely new for the wool dyer. According to his previous ideas, severe wool damage caused by the strong alkali present and the long storage times required for fixation had to be expected. Long-held and well-founded prejudices have to be overcome in order to arrive at the invention set forth herein.

Surprisingly, it was found in this connection that the damage to the wool is significantly less than expected, especially if urea is not added to the padding liquors.

Now the fixation of reactive dyes from an alkaline environment by lingering according to the European patent application EP-A1-0 126 026 has probably already been proposed for the dyeing of silk or silk-containing mixed fiber materials. However, silk, especially wild silk, is far less sensitive to alkaline influences in the field of work in this field than was assumed for wool. For example, the degassing of silk is carried out using soda-alkaline liquors. For the reasons set out above, the use of alkaline conditions in general for the treatment of wool fibers has therefore remained closed. If measures of this kind were occasionally unavoidable, then they were carried out as briefly as possible and at most from ammoniacal baths. A transfer of the experience gained in the silk field for use on wool was in no way obvious under these circumstances.

Suitable reactive dyes for carrying out the process according to the invention are all chemical compounds listed in the Color Index, 3rd edition 1971 and supplements 1975 under the generic term "reactive dyes", which form a covalent bond with fibers containing OH groups and / or NH groups are able to. In particular, such dyes with reactive groups of the vinyl sulfone type give significantly higher color yields and better fastness properties under the conditions of this invention than in the case of the known processes when using acid padding liquors.

In addition to the dye, other padding aids of the usual kind, such as wetting agents or aids for promoting or preventing dye migration, can be used in the padding liquors, should this prove to be necessary.

By adding up to a maximum of 50 g / 1 urea, a better one can often be carried out under the risk of greater wool damage. Product image, especially with regard to the so-called gray veil can be obtained.

• a) Verfahren mit Natronlauge/Kochsalz als Fixieralkali
  • Zum Ansetzen der wäßrigen Klotzflotte werden zunächst 2 Lösungen hergestellt. Die erste enthält Farbstoff und Kochsalz, die andere die benötigte Natronlauge. Beide Lösungen weisen Raumtemperatur auf.
  • Unmittelbar vor dem Klotzen der Wolle werden diese beiden Lösungen im bestimmten Verhältnis vereinigt und die so erhaltene Flotte wird dann auf das Textilgut aufgeklotzt. Die Flottenaufnahme kann dabei in weiten Grenzen (zwischen 50 und 130 Gew.-%) variieren. Danach wird zur Farbstoff-Fixierung die geklotzte Ware 6 bis 24 Stunden bei Raumtemperatur verweilt, was üblicherweise im aufgerollten Zustand unter langsamem Rotieren der Kaule erfolgt. Zweckmäßigerweise wird diese Maßnahme unter weitgehendem Luftabschluß vorgenommen, was durch Einschlagen der aufgedockten Ware in eine Plastikfolie erreicht wird. Bei entsprechend niedriger Flottenaufnahme kann der Verweilprozeß mit dem feuchten Textilgut auch in abgetafeltem Zustand bewerkstelligt werden. Anschließend wird hergestellte Färbung gespült, gewaschen und abgesäuert.
  • Das Verfahren nach Variante a) weist gegenüber dem nachfolgenden (Variante b) den Vorteil auf, daß nach Abschluß der Färbebehandlung die nicht umgesetzte Lauge leichter ausgespült werden kann als ein Gemisch Lauge/ Wasserglas; gegebenenfalls kann die erhaltene Färbung direkt mit Säure neutralisiert und sauer gestellt werden.
• b) Verfahren mit Natronlauge/Wasserglas als Fixieralkali
  • Bei größeren Metragen an zu färbender Ware werden die wäßrige Farbstofflösüng und die Lösung von Natronlauge/ Wasserglas ebenfalls getrennt angesetzt und dann unter Mischung entsprechend dem vorgegebenen Verhältnis kontinuierlich oder portionsweise in den Foulardtrog eindosiert.
  • Im Falle der Färbung kleinerer Metragen können die wäßrigen Flotten gemeinsam angesetzt werden, wobei allerdings das Gemisch Natronlauge/Wasserglas der Färbeflüssigkeit erst unmittelbar vor dem Klotzvorgang zugegeben wird. Diese Variante kann auch in Betracht gezogen werden, wenn niedrige Natronlauge/Wasserglas-Mengen zur Anwendung gelangen (siehe Beispiel 1). Im übrigen wird zur Farbstoff-Fixierung wie beim Verfahren gemäß Variante a) vorgegangen.
  • Bei der Nachbehandlung der Färbung gemäß Variante b) ist zu beachten, daß die Ware zunächst gründlich mit Wasser gespült wird, bis alles Wasserglas ausgewaschen ist. Erst dann darf die so erzeugte Wollfärbung angesäuert werden.

The two process variants are generally carried out as follows:

• a) Process with sodium hydroxide solution / table salt as fixing alkali
  • To prepare the aqueous padding liquor, 2 solutions are first prepared. The first contains dye and table salt, the other the necessary sodium hydroxide solution. Both solutions are at room temperature.
  • Immediately before padding the wool, these two solutions are combined in a certain ratio and the resulting liquor is then padded onto the textile material. The liquor intake can vary within wide limits (between 50 and 130% by weight). Thereafter, the padded goods are held for 6 to 24 hours at room temperature for dye fixation, which usually takes place in the rolled-up state with slow rotation of the ball. This measure is expediently carried out with the absence of air, which is achieved by wrapping the docked goods in a plastic film. If the liquor intake is correspondingly low, the dwelling process with the moist textile goods can also be carried out in a de-tabulated state. The dye is then rinsed, washed and acidified.
  • The method according to variant a) has the advantage over the following (variant b) that according to Ab conclusion of the dyeing treatment, the unreacted alkali can be washed out more easily than a mixture of alkali / water glass; if necessary, the dyeing obtained can be neutralized directly with acid and made acidic.
• b) Process with sodium hydroxide solution / water glass as fixing alkali
  • For larger amounts of goods to be dyed, the aqueous dye solution and the solution of sodium hydroxide solution / water glass are also prepared separately and then metered into the padding trough continuously or in portions, in accordance with the predetermined ratio.
  • In the case of coloring smaller batches, the aqueous liquors can be prepared together, although the sodium hydroxide solution / water glass mixture is only added to the coloring liquid immediately before the padding process. This variant can also be considered if low amounts of sodium hydroxide / water glass are used (see example 1). Otherwise, the dye fixation is carried out as in the method according to variant a).
  • When treating the dyeing according to variant b), it should be noted that the goods are first rinsed thoroughly with water until all the water glass has been washed out. Only then can the wool dyeing so produced be acidified.

According to the present invention, dyeings with good color yields and high fastness properties are obtained in these two ways, even with dyes of the vinylsulfone type.

Particularly good dyeing results can be achieved on chlorinated wool qualities or those which have been given a felt-free or low-felt finish by applying a polyacrylic or polyimine resin film.

example 1

• 15 g/1 des Farbstoffes Reactive Blue 19 mit der _C._I.-_Nr. ₆₁₂₀₀,
• 2 g/1 eines Netzmittels auf Basis von mit 8 Mol Ethylenoxid pro Mol umgesetztem Isotridecylalkohol,
• 5 em3/1 Natronlauge 32,5 %ig (38° Be) und
• ₅ cm³/1 Wasserglas von 38°C Bé.

zusammengesetzt ist. Die Flottenaufnahme beträgt hierbei 94 %, bezogen auf das Gewicht des trockenen Fasermaterials. Nach dem Klotzen sowie Abquetschen des Flottenüberschusses wird das feuchte Textilgut aufgedockt und zur Farbstoff-Fixierung 16 Stunden bei Raumtemperatur unter langsamem Rotieren der Kaule gelagert.A fabric is knocked out of wool which has not been pretreated with anti-felting equipment by means of a liquor of 20 ° C. which is made up of an aqueous solution of

• 15 g / 1 of the dye Reactive Blue 19 with the _{C. I N} .- r. ₆₁₂₀₀ ,
• 2 g / 1 of a wetting agent based on isotridecyl alcohol reacted with 8 moles of ethylene oxide per mole,
• 5 em3 / 1 sodium hydroxide solution 32.5% (38 ° Be) and
• ₅ ^cm3 / 1 Water glass of 38 ° C Bé.

is composed. The liquor absorption is 94%, based on the weight of the dry fiber material. After padding and squeezing off the excess liquor, the damp textile material is docked and stored for 16 hours at room temperature with slow rotation of the ball to fix the dye.

Then the wool dyeing produced in this way is first rinsed thoroughly with water at 20 ° C. Avoid temperatures higher than 40 ° C during the rinsing process as long as the goods are alkaline. The colored substrate is then neutralized by treatment with acetic acid and rinsed again with water.

A clear, level blue dyeing of the wool is obtained.

By adding up to 50 g / 1 urea to the padding liquor, the surface appearance of the dyeing can be further improved. In this case, urea does not act as a swelling agent for the fiber, but serves to increase the solubility of the dye.

Example 2

• (I) 37,5 g/1 des Farbstoffes Reactive Black 5 mit der C.I.-Nr. 20505,
• 6,25 g/l eines Netzmittels auf Basis eines Umsetzungsproduktes von 1 Mol Isotridecylalkohol mit 8 Mol Ethylenoxid, sowie
• 37,5 g/1 Kochsalz
  enthält, sowie eine zweite wäßrige Flotte von etwa gleicher Temperatur aus
• (_II) ₇₀ cm³/1 Natronlauge 32,5 %ig (38° Bé).

An aqueous liquor of (25 ° C.) is prepared, which

• (I) 37.5 g / 1 of the dye Reactive Black 5 with the CI no. 20505,
• 6.25 g / l of a wetting agent based on a reaction product of 1 mol of isotridecyl alcohol with 8 mol of ethylene oxide, and
• 37.5 g / 1 table salt
  contains, as well as a second aqueous liquor of approximately the same temperature
• _{(II) 70} cm ^3/1 sodium hydroxide solution of 32.5% strength (38 ° Be).

Both fleets I and II are mixed immediately before padding by means of a metering device in a volume ratio of 4: 1 and thus a fabric made of wool which has been made felt-free by chlorination is padded with a liquor absorption of 100% by weight. The moist textile web is then docked as in Example 1, the residence time for dye fixing at room temperature in this case is 24 hours.

For post-treatment, the dyed goods are first rinsed thoroughly with water, neutralized with acetic acid, then washed for 15 minutes at 60 ° C by treatment with ammonia in an alkaline medium at pH 8.5, rinsed again with water and finally acidified (acetic acid).

You get a level, real anthracite color of the wool.

Example 3

• (I) 60 g/1 des Farbstoffes Reactive Black 5 mit der C.I.-Nr. 20505 und 10 g/1 des Netzmittels aus Beispiel 1,
• (II) 290 cm³/1 Wasserglas von 38° Be und 4₀ cm³/1 Natronlauge 32,5 %ig (38° Be),

A woolen fabric made from Schur wool is padded at 100% by weight liquor absorption with an aqueous liquor at 20.degree. C., which is prepared by metering together the two stock solutions I and II given below in a volume ratio of 1: 1, the same as water as further constituents in detail

• (I) 60 g / 1 of the dye Reactive Black 5 with the CI no. 20505 and 10 g / 1 of the wetting agent from Example 1,
• (II) 290 ^cm3 / 1 Water glass of 38 ° Be, and 4 ₀ cm ^3/1 sodium hydroxide solution of 32.5% strength (38 ° Be)

exhibit. Otherwise, the block procedure is as in Example 1. The residence time for dye fixation here is 24 hours.

Under the above conditions, the result is a slightly weaker anthracite color than that according to Example 2, which is due to the use of chlorinated wool as a textile in the previous example.

Example 4

• (I) 40 g/1 des Farbstoffes Reactive Red 4 mit der C.I.-Nr. 18105, 6 g/1 eines nichtschäumenden, anionischen Netzmittelgemisches und 30 g/1 eines Klotzhilfsmittels auf Basis von Acrylsäureester-Copolymerisaten.
• (II) 100 cm³/1 Wasserglas von 38° Bé und 100 cm³/1 Natronlauge 32,5 %lg (38° Bé).

The procedure for padding a wool jersey, which is equipped with a polyimine resin coating to make it felt-free, is as in Example 3, but in the present case the following aqueous padding liquors are used, which are mixed together according to the ratio described there before the application operation:

• (I) 40 g / 1 of Reactive Red 4 dye with CI no. 18105, 6 g / 1 of a non-foaming, anionic wetting agent mixture and 30 g / 1 of a padding aid based on acrylic acid ester copolymers.
• (II) 100 ^cm3 / 1 Water glass of 38 ° Bé and 100 cm ^3/1 sodium hydroxide 32.5% lg (38 ° Be).

After the dwell time of 12 hours, subsequent rinsing, subsequent ammoniacal aftertreatment and finally acidifying the goods, a real, red color of the wool jersey is obtained.

Claims (6)

1. pad-cold dwelling process for dyeing wool with reactive dyes, characterized in that the fiber material with the dissolved reactive dyes having aqueous liquors pad at a pH between 9 and 13 and then this padding for dye fixation in the moist state 6 can stay up to 24 hours at temperatures up to a maximum of 25 ° C, preferably in the range of room temperature, under the customary strongly alkaline conditions. 2. The method according to claim 1, characterized in that a mixture of sodium hydroxide solution and water glass in the ratio of 1: 1 to 1:10 and in amounts of 5 g / 1 to 250 g / 1 is used in the padding liquors as fixing alkali. 3. The method according to claim 1, characterized in that one uses in the padding liquors as fixing alkali sodium hydroxide in amounts of 5 g / 1 to 60 g / 1. 4. The method according to claim 3, characterized in that the padding liquors additionally contain up to 50 g / 1 table salt or Glauber's salt. 5. The method according to one or more of claims 1 to 4, characterized in that the padding liquors do not contain urea. 6. The method according to one or more of claims 1 to 5, characterized in that pretreated by chlorination, or provided with a pad made of a polyimine resin or a polyacrylic resin, low or felt-free finished wool.