DE3151466A1 - "METHOD AND DEVICE FOR FIXING CATIONIC DYES ON POLYACRYLNITRILE FIBERS IN THE GEL STATE" - Google Patents

Description

HOECHST AKTIENGESELLSCHAFT HOE 81 / E 334 + H Dr.CZ/cr

Method and device for fixing cationic dyes on polyacrylonitrile fibers in the gel state

The present invention relates to the continuous Fixing of cationic dyes in the course of the manufacturing process on cables made of polyacrylonitrile fibers in a conventional wet spinning process Gel state according to a dip dyeing / dwell technique.

According to the methods currently used in practice anionically modified polyacrylonitrile fibers in the gel state dipped in a liquor with cationic dyes for dyeing, for dye fixation continuous operation during a. Leave residence time between 5 and 20 seconds in the dyebath and then rinsed to complete the dyeing with or without prior squeezing of the fiber material.

15. In most cases, a large amount of dye is contained in the dye liquor carried along by the transport of goods Dye washed out again, i.e. strongly colored washing water results and you therefore suffer a noticeable Loss of dye. Apart from the heavily polluted wastewater that contributes to environmental pollution, also leave the authenticity properties of in such Colorings obtained in this way as a result of insufficient dye fixation much to be desired.

In order to achieve better staining results in this regard, in many cases one has gone over to the textile material treated with the dye liquor has more time available through a certain period of dwell to provide adequate fixation of the dyes

bring about. Such a dwell under |

When dyeing a web of goods, goods can be deposited without i

further switched on in the dyeing process, at \

Yarns and threads, however, are already difficult to find l to accomplish, in the case of gel fibers, however, one has because of

the sensitivity of this material such an approach hitherto not considered possible, quite apart from the fact that a continuous lingering of gel fibers unaffected * - is known.

· The object of the present invention is now, while maintaining the favorable aspects of a Gel coloring to eliminate the problems identified in this connection and the disadvantages mentioned above to avoid this way of working. In addition, in the context of the coloring of fiber cables made of acrylonitrile polymers in the gel state, it is very difficult, especially in the case of a total titre of more than 1,000,000 dtex is a uniform penetration and a quick and uniform fixation over the entire fiber cable cross-section to achieve. An improvement in the known dyeing technique should therefore be based on a short Residence process can be tapped, but without questioning the continuous process principle.

.

According to the invention, this object is achieved in that Following the coagulation process, the spun material, which runs continuously in strand form and is then soaked with dye liquor, after intensive squeezing of the liquid Keitseitses introduces for dye fixation by lingering in a goods store while there the passage, e.g. when put down or guided over rollers, sieve belts or sieve drums, the action of exposing it to moist heat and then continuously removing it from the store, whereupon the so-colored Fiber cable is rinsed and further treated ".

The conception of the measures applied according to the invention is thus based on the fact that one can use the dye liquor introduces relatively saturated goods after sufficient squeezing into a dwell zone in which the

Dye is given a reasonable time to fix. If necessary, the goods are heated up immediately before they enter the dwell zone, which means that the fixing time is reduced shortened. Since the process takes place continuously, it can be used immediately after leaving the dwell zone the dyed fiber tow can be rinsed and washed. Instead of a very cumbersome and time-consuming one The dyeing process is therefore a continuously running, easily surveyable and controllable dyeing process kicked. By using the reference method for dye fixation according to the new process is achieved that the fixation of the cationic dyes on the gel fibers not only continuously but also extremely gentle on the fibers at the same time as well as quickly. The dye fixation is complete, the fastness properties of the dyed fibers are good.

In detail, the dyeing process proceeds according to the process the following way abt

The fiber cable coming from the immersion bath or from the impregnation bath and soaked with dye liquid is first squeezed off and freed from the excess liquor. The squeegee located behind the dye bath for this purpose, the cable harness should be as good as possible to a liquor pick-up of 100 to 200% (based on the weight of the dry goods), preferably 120-170% by weight are desired. The more the material is squeezed the faster the dye fixation then takes place.

The dye liquor is normally applied at room temperature or at a moderately elevated temperature. To increase the fixing speed, it is in principle possible to apply the pre-heated preparation liquid. It is considered to be much more expedient for this project

315U66

-6-

- as already mentioned above - but proved that impregnated with the dye preparation fiber cable after squeezing, however, heat immediately prior to entry into the product storage during one pass through a heating tunnel at 50 ° to 100 ⁰ C and to bring approximately at fixing temperature.

Following the impregnation treatment for dye application, the reduction of the goods from excess fleet quantities and, if necessary, after interim After heating, the moist strand material is fed to a dwell zone, which it is in accordance with that for the Dye fixation required time passes more or less rapidly. Only when the fixation of the When the dye is finished, the rinsing of the dyed fiber tow with water, as well as the measures, follow for further treatment such as stretching, relaxing, drying, etc.

The article storage itself, ie the residence zone may be operated with or without a separate heating, for example at 20 ° to 60 ⁰ C, but preferably is allowed to the product at an elevated temperature, ie, stay at 50 ° to 100 ⁰ C. .

The temperature control in the goods store, as well as in a possibly preceding heating zone, can by means of high-frequency radiators (microwaves), by means of direct steam or by means of indirect steam, e.g. by heated guide rollers take place. The higher the dwell temperature, the shorter the fixing time for the dye. The stay of the dyed spun material in the dwell zone is, according to the invention, from 5 to 120 seconds, preferably 10 to 60 seconds.

In the context of the above measures, the dwell operation comes the crucial importance that the

3Ί5Η66

Dyes evenly over the entire cable cross-section let fix. In contrast to previous methods, even large amounts of dye are really fixed here. In the case of deep dyeings, however, you will never work without a heated dwell zone.

The effectiveness of the dwell operation can with the invention The method can be reinforced by the fact that the fiber cable during the passage through the Repeatedly heated goods storage system, possibly also squeezed alternately from different sides. In this respect it was extraordinarily surprising and could not have been foreseen that such a thing mechanical treatment in the dwell zone, i.e. in a heated chamber, for a very quick fixation, leads.. . . .

One for carrying out the novel dip dyeing / dwell process suitable device, to which the present invention also relates, consists - each referred to in the direction of movement of the continuously running cable strand (1) - essentially from one Impregnation zone (2) containing chassis for immersion or impregnation bath (not shown), including the following Pair of rollers (3), placed transversely to the flow of goods, for dewatering the soaked with excess dye liquor Spun material (1) by squeezing pressure; a heating zone (4), essentially for the application of radiant energy, Steam or contact heat on the goods; and a dwell zone (5), which is designed as a goods storage (6) and means for guiding the strand material (1) through with little tension during the dwell phase for dye fixation having. This residence zone (5) is according to the invention characterized in that therein (5) transversely to the direction of goods travel - at least at the goods inlet and the goods outlet - In addition, several squeezing units / roller pairs (7) for the transported through the Waronspcicher (6)

Cable (1), in a parallel position to one another or advantageous are arranged in a position rotated against one another by an angle of up to 90 °, if necessary alternately in combination with heating fields (8).

With this design of the dwell zone, it is envisaged that impregnation liquor stuck together, Filaments of the strand adhering to one another in parallel are detached from one another again and the strands are thereby loosened and opened, whereby a higher uniformity of the coloration of the cable harness as well results in better dwell operation efficiency.

The goods storage, which is used to linger for the fiber tow soaked with dye liquor and often already preheated can be designed quite differently: In the simplest case, it is a heated chamber with an inclined floor on which, due to the inclined position, the spinning material is in an approximately paneled state after Exit to glides - Systems in a kind of roller skid are also usable for this purpose, also let use chambers with sieve drums. Finally, they are suitable for transporting materials through the warehouse endlessly circulating sieve belts, if necessary subdivided on several individual belts and arranged one above the other, on which the strand material is placed.

Particularly advantageous conditions exist when within the scope of the device according to the invention, heating zone (4) and dwell zone (5) / i.e. Goods storage (6) including nip rollers (7) and heating fields (8) _7 in a closed by means of goods inlet and outlet, common container (9) are housed. Residence zones with heated chambers that are spacious enough in order to offer both crushing devices at the entrance and exit, as well as a storage space, therefore have the highest Efficiency.

VL .. Ί \ ^: .: ^:: "^ 315U66

Another variant in the formation of such dwell zones is that at the entrance to the dwell chamber a microwave heater is attached, which heats the material to the desired temperature and in the chamber there is again a heater in order to to prevent the fiber cable from cooling down. In such systems, the residence time is low, as a result the speed of the goods is relatively high.

The present invention will be explained with reference to drawings explained in more detail. The figures shown show the side view of a schematic representation Continuous road, whereby according to Figure 1, the goods storage is designed as a slide on which the boarded Strand material is exposed to the dwell operation α Figure 2 contains a variant of such a device, according to which the goods storage device alternates between squeezing units and over the length of the dwell path Heating fields is interrupted. The reference symbols used here are the same as those in the above text for this Purpose used digits identical.

For the process according to the invention, cationic : Dyes from both mono-cjuartar and bisquaternary Type are used., Which belong to the most diverse chemical compound classes, so in particular the class of monoazo dyes, disazo dyes, the methine, azamethine and diazamethine dyes and the naphthalactam dyes.

.

Besides, the polymers of acrylonitrile come for the Use according to the claimed process as substrates to be spun, copolymers of acrylonitrile with other vinyl compounds into consideration, v / obei these copolymers at least 50 wt .-%, preferably have at least 85% by weight of acrylonitrile units.

3T5U66

-Ίο-

The acrylonitrile homopolymers or their copolymers used are mostly acid-modified.

For dyeing, in the present case, the undrawn fibers or filaments - without being dried - treated at temperatures between 10 ° and 100 ⁰ C, preferably between 20 ° and 80 ⁰ C, with the dissolved in an aqueous or solvent-based dyeing dyes. The dyeing time is generally between 0.5 and 20 seconds, preferably between 2 and 20 seconds. The stated dyeing time corresponds to the contact time (residence time) of the polymer with the dye solution after spinning.

According to the method, the dyeing operation itself is continuous in the course of the manufacturing process of the fiber tow made, i.e. as long as the freshly spun acrylonitrile polymers are in gel-like form. It can be carried out during or shortly after the coagulation process of the polymer.

The colored fiber cables are then cleaned under normal conditions with steam or hot air fixed, stretched, finished and, if necessary, dried with the approval of shrinkage.

The following examples serve to illustrate the invention. The parts and percentages given therein are parts by weight and percentages by weight, unless otherwise noted.

- ff -

example 1

An acrylonitrile copolymer of 85% acrylonitrile, 14.5% vinyl acetate and 0.5% sodium vinyl sulfonate is produced in the form of a 28% spinning solution in dimethylformamide according to standard conditions at 80 ^° C. using a 100-hole spinneret with a hole diameter of 80 µm wet spun, using a coagulation bath at 50 ° C., which consists of 50% dimethylformamide and 50% water.

After a squeezing process, the thread material obtained passes through an impregnation zone without prior drying. in which a solution of 0.1 g of a mono-quaternary dye made to pH 4.5 by means of acetic acid formula

N =

/ Λ

-N-CH ₂ -CH ₂ -CN

ZnCl

acts on the material in 25 l of water at room temperature. Thereafter, the spun material is squeezed off, was heated by microwave at 80 ⁰ C and introduced into a chamber where it passes through 4 horizontally and vertically standing nips then stored briefly, rolled twice and is finally guided back from the 80 ⁰ C hot chamber. The total dwell time during the passage of the goods is 40 seconds. The threads treated in this way are then rinsed with water, stretched as usual, relaxed and dried.

A blue dyeing with excellent fastness properties, mainly particularly good wet fastness properties, is obtained very good light fastness.

Example 2

An acrylonitrile copolymer made of 94% acrylonitrile » 4% vinyl acetate, 1% Na itaconic acid and 1% Na methallyl sulfonate is in the form of a 28% spinning solution in dimethylformamide according to standard conditions such as spun wet in Example 1 and passed through a coagulation bath.

The thread material obtained is squeezed off and passes through an impregnation zone without prior drying, in which is a solution of 0.1 g of a bis-quaternary dye made to pH 4.3 by means of acetic acid formula

0-CH ₂ -CH ₂ -N (CH ₃ )

2 BF

allowed to act on the material in 2.5 l of room temperature water. Thereafter, the spun material is squeezed, heated by means of indirect vapor at about 70 ⁰ C and passes at about the same temperature, a chamber in which it is continuously exposed to the action of nip rolls. The passage of goods under these conditions takes place without tension, so that the material opens again after each squeezing. The material remains in the chamber for a total of 10 seconds. After leaving the chamber, the threads treated in this way are rinsed with water, then stretched, relaxed and dried as usual.

-W-

A reddish-tinged yellow is obtained on the fiber cable excellent fastness properties, mainly particularly good wet fastness properties and very good light fastness properties.

- // if.

Blank page

Claims (1)

. HOE 81 / F 33-4 + Η PATENT CLAIMS ο Process for the continuous fixation of cationic Dyes in the course of the manufacturing process on cables produced by a conventional wet spinning process made of polyacrylonitrile fibers in the gel state, characterized in that, following the coagulation process, the continuously running in strand form and then spun material soaked with dye liquor after intensive squeezing off of the excess liquid for dye fixation by staying in one Bringing goods storage, exposing there to the action of moist heat during the passage and finally continuously removed from the goods store, whereupon the fiber cable dyed in this way is rinsed and further treated will. 2- A method according to claim 1, characterized in that the fiber cable is heated immediately prior to entry into the product storage during the passage through a heating duct at 50 ° to 100 ⁰ C. 3 "Method according to claim 1 or 2, characterized in that that the fiber cable is additionally heated during the passage through the goods storage. 4. The method according to claims 1 to 3, characterized in that the fiber cable during the passage through the storage device is repeatedly and severely squeezed off and, if necessary, alternately. 5. Process according to Claims 1 to 4, characterized in that that the dwell time of the fiber cable in the goods storage 5 to 120 seconds, preferably 10 to 60 seconds. ffl HOE 81 / F 334 + H 6. Device for performing the method according to Claims 1 to 5, consisting - each in the direction of movement of the cable harness to be treated - from an impregnation zone and subsequent Pair of squeeze rollers, positioned transversely to the flow of goods; a heating zone; as well as a dwell zone, which is called Goods storage is formed and has transport means for the strand material to be passed through, thereby characterized in that in the dwell zone (5) transversely to the direction of movement of the goods - at least at the goods inlet and at the goods outlet - additional squeezing devices (7) for the cable guided through the goods storage (6), in a parallel position to one another or advantageously rotated to one another by an angle of up to 90 ° Position are arranged, optionally alternately in combination with heating fields (8). 7. Apparatus according to claim 6, characterized in that the heating zone (4) and dwell zone (5) J_ goods storage (6) including nip rollers (7) and heating fields (8) _7 housed in a common container (9) closed by means of goods inlet and goods outlet are.