DE2511536C2 - Process for the continuous dyeing of cellulose fibers with sulfur dyes and their derivatives - Google Patents

Description

Dc: s dyeing of sulfur, leuco sulfur and thiosulfato dyes on cellulose fibers has been since known for a long time.

Likewise, continuous KIotz dyeing processes are known for these dye classes, in which the Leuco (sulfhydryl) form of the dyes from cold and warm liquors padded onto the goods, through a steam pro / ß fixed and by an oxidizing after-treatment in the broad state in the water-insoluble Disulfide form of dyes (basic form of sulfur dyes. Starting form for their water-soluble ones Derivatives such as leuco-sulfur and thiosulfato dyes) on the fiber / is regressed. the The leuco form of the sulfur and thiosulfato dyes is thereby preferred by reducing agents Sulfur sodium, formed in one or two baths. Against it the leuco sulfur dyes are already present as a reduced (sulfhydryl) level and do not require any Reducing agent additives. The fixation of the I. end connections on the fiber is always done by steaming.

The dyeing of these dye classes Mi is also more analogous Way on the roller skid. i.e. after a continuous exhaust process, preferably without a steaming process, is exercised in practice. The different affinity behavior of the individual dye components and the unfavorable ratio of goods to fleet makes this procedure particularly difficult, The amount and timing of the follow-ups must be monitored very carefully in order to be reasonably correct to achieve cendengleich.cn and level colorations,

For the dyeing of light to medium depths of color, see W. B e r η a r d, »Practice of bleaching and Dyeing of textiles ", Springer-Verlag 1966, page 208 ff. Known a method in which water-soluble Sulfur dyes with full, unreduced additions of reducing agents, i.e. sodium sulfide or sodium hydrogen sulfide, padded at over 60 ° C, in an air passage of at least 20 seconds fixed and then oxidized. This procedure

there is the great disadvantage that the dyes are fully reduced and with a very negative redox potential be padded onto the fiber. Due to the negative redox potential transferred to the entire product arise in the air passage and in the

ίο subsequent oxidation difficulties because of it there is a strong tendency to spontaneous oxidation before the dye is properly fixed. A hint for this fact, the recommendation provides dye and reducing agent because of better color penetration to block separately from each other.

It has now been found that the continuous dyeing of cellulose fibers in Bahn'orm with sulfur, leuco-sulfur and thiosulfato dyes by a single-bath, economical process in which the textile material from a small trough with a temperature above 6Ü ^J C heated, aqueous liquor of one or more of these dyestuffs in leuco form, the goods treated in this way are subjected to an air cycle of at least 10 seconds, preferably 30 to 40 seconds, expediently at room temperature, and then immediately afterwards without prior intermediate drying and steaming (in the otherwise The reoxidation of continuous sulfur dyeings usual way) on the wide washing machine by rinsing, acidic oxidation and rinsing the water-insoluble disulfide form of the dyes on the fiber back again, the above-mentioned problems can be remedied if a dye solution is used as the padding liquor, which a sodium polysulfi before use d of the formula Na ₀ S ₁ , in which .r is a number from 2 to 5, has been added in the form of its aqueous solution, and when this liquor is applied to the textile material at 90 to 95.degree.

The use of the sodium polysulfide solution in the Klotzfiotte according to the invention Procedure prevents the spontaneous oxidation of the leuco dyes by the oxygen in the air during of the air passage.

The very negative redox potential of the excess sodium sulfide (low rH value) is due to Formation of disulphides with a more positive redox potential weakened (somewhat higher rH value). through which the aggressiveness of the oxygen in the air is canceled for the duration of the air passage. Takes place at the same time a decrease in fascru, ullage. what to the Coloring through is very beneficial. The spontaneous oxidation in the air passage is so annoying because it causes the compensating diffusion into the interior of the fiber is interrupted, which affects both the levelness (product image) and dye yield (the dye remains on the surface of the fiber) and on the dyeing (inside of the thread or fiber) less dye) has a detrimental effect.

The use of a small Hottentrog or of a chassis with a displacement body a very quick flotation, so that the Affinity of the leuco form of the dye for the fiber does not have an effect in terms of an end mismatch

«S kafiti.

The sodium polysulphide used in the process of the invention becomes the padlocks expediently as about 15% aqueous solution in one

Amount of 15 to 25 cnWl added.

On the following technical advantages of the method according to the invention over the method of State of the art is referred to:

Excellent color loss in terms of levelness, color penetration and the same ends.

Full dye yield even in deep shades, which also have improved wet and rub fastness properties compared to roller skid dyeing as a result of the undisturbed diffusion of the dye into the fiber became.

The practical application of the principle according to the invention is shown in the following examples, but not limited to these.

example 1

A cotton twill is at a liquor pick-up of 80% (of the fabric weight) and a fabric speed from 30 m / min on a padder with a small chassis with a 90 to 95 ° C hot, - ° padded aqueous liquor, which contains per liter:

140 g of the dye Leuco Sulfur Green 9,

Cl no. 53005,
20 g of the dye Leuco Sulfur Brown 51,

Cl no. 53377,
3 g of an anionic wetting agent based on alkanesulfonate and

20 g of a 15% strength aqueous solution of a sodium polysulphide with an average S content of 2 to 5 atoms per molecule.

3 g of an anionic wetting agent based on

Alkanesulfonate,
120g of 21% aqueous sodium hydrogen

sulfide solution,
20 g soda lime. and

20g of a 15% strength aqueous solution of a sodium polysulfide with an average S content of 2 to 5 atoms per molecule.

After padding, the goods have a 15 m air passage (corresponding to 30 seconds). The sodium polysulphide prevents the spontaneous oxidation of the sulfhydryl form of the dyes in the air passage and thus enables in the exposure time of 30 seconds a complete and undisturbed diffusion of the dyes and their uniform fixation.

The textile material treated in this way is, as is customary for sulfur dyeing on piece goods, on the Wide washing machine further treated by rinsing, acidic oxidation and rinsing.

The result is an olive shade with a very good shade, calm fabric appearance, good equality of ends and one that corresponds to the amount of dye used Color depth.

₄₀

After padding, the goods are air-walked 15 m (corresponding to 30 seconds).

The further and post-treatment of the padding is then carried out on the wide washing machine by rinsing, acid oxidation and rinsing, as is customary for dyeing with sulfur dyes on piece goods.

The result is a deep olive nuance with very good color penetration, a smooth appearance, good end smoothness and full dye yield on the dense twill.

Example 2

A cotton twill is at a liquor pick-up of 80 ",, (from the weight of the goods) and a goods speed of 30 m / min on a padder with a liquor trough and displacement body with a aqueous liquor padded from 90 to 95'C, which contains per liter:

55 g of the dye Solubilized Sulfur Green 9,

CM no. 53006.
10 g of the dye Solubilized Sulfur Brown 60, Cl no. 53326.

Example 3

A heavy cotton fabric is ^{padded with a liquor pick-up of 80 D} "(of the fabric weight) and a fabric speed of 30 m / min on a padder with a low volume liquor chassis with an aqueous liquor of 90 to 95 ° C, which contains per liter:

45 g of the dye Sulfur Brown 10,
Cl no. 53055,

30 g of the dye Sulfur Red 6,
Cl no. 53 720,

25 g of the dye Sulfur Brown! 6,
Cl no. 53285,

80 g sodium sulfide (sulfur sodium conc.),

20g of a 15 "strength aqueous solution of a sodium polysulfide with an average S content of 2 to 5 atoms per molecule, and
3 g of an anionic wetting agent based on alkanesulfonate

After padding, the goods are ventilated 15 m (corresponding to 30 seconds) and post-treatment on the wide washing machine by rinsing, acidic oxidation and rinsing, in the other for dyeing with sulfur dyes in the usual way.

It results in a running brown shade with a very good one Dyeing through, smooth product appearance, good end uniformity and full dye yield.

Claims (2)

25 claims: 1. Continuous process for single-bath dyeing of cellulose fibers in web form with sulfur (CI Sulfur Dyes), leuco sulfur (CI Leuco Sulfur Dyes) and thiosulfate (CI Solubilized Sulfur Dyes) dyes, whereby the textile material from a small liquor trough with a heated to temperatures above 60 ° C, aqueous liquor of one or more of these dyes in leuco form, subjects the treated goods to an air passage of at least 10 seconds and through reoxidation on the wide washing machine, the water-insoluble disulfide form of the dyes on the fiber back again, characterized in that a dye solution is used as padding liquor to which a sodium polysulfide of the formula Na., S _x , where χ is a number from 2 to 5, has been added in the form of its aqueous solution before use, and that this liquor is at 90 to 95 ° C is applied to the textile material. 2. The method according to claim 1, characterized in that padding liquors are used, 15 to 25 cnvVl of an approximately 15% aqueous solution of the defined in claim 1 before use Sodium polysulfide has been added.