WO2007101617A1

WO2007101617A1 - Process for the semi-continuous dyeing of woven and knitted fabric and also equipment for practicing the process

Info

Publication number: WO2007101617A1
Application number: PCT/EP2007/001804
Authority: WO
Inventors: Klaus-Uwe Moll; Hans Seelen; Stefan Krebs; Jürgen SÜSS-LEONHARDT; Peter Tolksdorf
Original assignee: Küsters Textile GmbH
Priority date: 2006-03-03
Filing date: 2007-03-02
Publication date: 2007-09-13
Also published as: DE102006010432A1

Abstract

The pad cold-batch process comprising the steps of applying dyeing liquor to the fabric, winding the fabric up, batching the fabric, unwinding the fabric, washing the fabric and drying the fabric is characterized in that the fabric(s) is heated to an elevated temperature after the applying of dyeing liquor to the fabric (5).

Description

Method for the semi-continuous dyeing of woven and knitted fabric and apparatus for using the method

The invention relates to the pad-cold stay process (short KKV process) for the semi-continuous dyeing of woven and knitted fabric of cellulosic fibers with reactive dyes, comprising the following steps:

- Order of dyeing liquor on the goods; Winding up the goods; Stay the goods; Unwinding the goods; Washing the goods; - drying the goods.

The KKV process is a widely used technique. The dye solution and the alkali required for fixation are fed to a container (dyeing trough or dyeing chassis) in which the product is impregnated (padded).

After padding, the product is wound into a roll of goods and usually wrapped in foil to prevent drying out of the fabric edges and the upper layers of the roll during the residence time, otherwise there is a migration of the dye. The fabric wrap dwells in this state, depending on the dye composition for a period of four to twelve hours, until the reaction of the reactive dyes is completed. Subsequently, the product is unwound from the goods roll again and fed to a usually continuous washing device for washing of unfixed dyes, alkali, etc. After the washing device, the product passes through a likewise usually continuous drying device to finally be wound up again to a goods roll.

Although the KKV process has found widespread use, it is disadvantageous that there is a considerable period of time between the application of paint and the final winding after drying. This period limits production flexibility, making production planning difficult.

In addition, the large time interval between the application of paint and the final result, which can only be checked after drying, makes it difficult to take corrective measures if the color loss on the final product is not desired.

The invention is therefore based on the object to further develop the known KKV method such that the production planning is facilitated.

This object is achieved by the method given in claim 1.

Surprisingly, it has been found that heating the fabric after the dye liquor is applied to the fabric at an elevated temperature leads to such an acceleration of the dyeing reaction that the residence time can be substantially reduced without this leading to a deterioration in the quality of the color failure.

The method requires that the dye liquor is at least substantially thermally stable up to this elevated temperature, ie, even at this temperature over a prolonged period does not tend to Hydrolysis. Because after the liquor order on the goods even when increasing the reaction rate of the dye with the goods, due to the elevated temperature, still requires a considerable amount of time until the reaction of the dye liquor with the goods at least largely completed and the bond is made. Dye, which is on the goods and has not yet reacted with the web, tends as well to the hydrolysis, as the same dye at the same temperature in the liquor basin. Since the liquor exchange times in dyebases with minimized liquor volumes are within a maximum of two to three minutes, the advantage of a preferably cooled liquor in the dyebox is largely that at lower liquor temperature, the lift behavior of the individual dyestuff components is usually less different from the substantivity differences than at higher liquor temperatures temperatures. A lower temperature in the dyebath therefore leads to lower color shifts on the product until equilibrium is reached in the dye bath, ie the length of time from color shifts is significantly reduced. Because of the low liquor exchange times (time of renewal of the dyebath) of a few minutes and compared to the significantly higher mean reaction times of the paint on the web, the hydrolysis in the dyebath, slowed by the reduced bath temperature, has an effect on the total hydrolysis (dyebath and ware). a rather subordinate influence.

Experiments have shown that to reduce the residence time with almost unrestricted dyeing quality, a heating of the product after the order of the dyeing liquor to a temperature of about 45 ° C is particularly suitable.

In a preferred embodiment of the method, the product is provided after winding with a sheath, for example by wrapping the fabric roll with an air-impermeable film to prevent drying of the edges of the product and the upper layers of the fabric roll.

In one embodiment of the method according to the invention, the product is supplied to a room after winding. This embodiment of the method has the particular advantage that the goods - as to increase the Reaction rate and thus reducing the residence time required for the complete reaction is particularly advantageous - can be kept at the elevated temperature by the atmosphere in the room is heated to the elevated temperature.

The temperature of the goods roll can also be done with a heating or even insulating sleeve to reduce the cooling rates.

In order to maintain the most even distribution of the dyeing liquor over the entire goods wrap during the residence time, it is advantageous if the goods wrap is rotated during the stay around the winding axis. This prevents dyeing liquor from accumulating in the lower area of the fabric wrap, which would lead to a divergence in color loss.

The achievable with the method according to the invention productivity can be further increased if the goods wraps are continuously displaced by the heated space. Depending on the size of the room and the length of stay, several fabric wraps can then be moved through the room at the same time.

Experiments have shown that with a warming of the goods and holding them during the residence time to about 45 ⁰ C, the residence time required for the course of the reaction typically 8 hours reduced to about 1, 5 hours.

A plant suitable for the application of the method according to the invention comprises an application device for applying the dye liquor to the goods, a winding device for winding the web after the application of the dyeing liquor to a goods roll and according to the invention a heating device for heating the goods to an elevated temperature before winding the goods to the goods winding. The heater may be configured as a heat radiator or steam ejector. The device according to the invention preferably further comprises a space into which the goods roll can be introduced.

This space is - particularly preferably - equipped with a heating device by means of which the goods roll can be kept at the elevated temperature. Due to this measure, it is unnecessary to provide the goods wrap for holding at the elevated temperature with heating or insulating sleeves.

Extensive automation of the implementation of the method according to the invention can be achieved if a conveying device is provided, by means of which the goods roll is continuously or discontinuously conveyed through the space and rotatable about the winding axis. The conveyor can then be operated at a speed which results in a retention of the fabric roll for the desired dwell time at the elevated temperature and with rotation of the fabric roll to avoid the accumulation of dye liquor in individual areas of the fabric roll.

The method according to the invention and the system suitable for the use of the method will now be described with reference to the attached drawing. Show it:

Fig. 1 - schematically - the equipment required for paint application and retention of the goods winding part in a side view and

Fig. 2 - also schematically - the need for washing and drying further part of the system.

The plant designated as a whole by 100 in the drawing comprises an unwinding station 1 in which a web-shaped, ready-to-use product 2 is unwound from a goods roll 3. The product 2 is continuously supplied to an application device 4 designed as a padder in the drawing for application of dyeing liquor to the product 2. The applicator can be equipped with a cooling device not shown in the drawing for cooling the fleet.

After application of the dyeing liquid, the now padded product 5 is heated by means of a heater 6, which is designed as an infrared radiator, uniformly over the entire width of the goods to a temperature of about 45 ° C. The radiated heating energy is symbolized in Fig. 1 with the arrow P. The heated, padded product 5 is fed to a winding station 7, in which it is wound up into a goods roll 8.

At the winding station 7 a device for film processing 9 is shown only schematically, by means of which the goods roll 8 can be wrapped with a film to prevent drying of the fabric edges and the upper layers of the roll.

Subsequently, a space 10 is fed by means of a symbolized by the arrows Q and T, not shown in detail conveyor the goods roll. It comprises a heating device 12, by means of which the atmosphere 11 located in it can be heated to a temperature which causes the goods roll 8 to be held at the elevated temperature of approximately 45 ° C.

The goods roll 8 is passed through the space 10 with rotation about the winding axis, as should be symbolized by the arrows R and S, wherein the speed is selected such that the goods wrap 8 is in the space 10 for the required residence time.

After the expiry of the residence time, which is typically about 1, 5 hours, the goods roll 8 is transferred to a further unwinding station 13, in which the web unwound and downstream, continuously working washing and drying devices 15, 16 is supplied. In the wash Device 15 unfixed dye and other residues from the web are washed out in a known manner and dried in the drying device 16, the product of the washing liquid.

After the drying process, the product is checked for color loss and fed to a winding station 14. The dyed, dried goods are wound up here to wrap goods.

LIST OF REFERENCE NUMBERS

100 plant

2 ready-to-use goods

3 goods winding

4 application device

5 padded goods

6 heating device

7 winding station

8 goods wrapping

9 device

10 room

11 atmosphere

12 heating device

13 unwinding station

14 winding station

15 washing device

16 drying device

P arrow

Q arrow

R arrow

S arrow

T arrow

Claims

claims:

1. pad cold padding process for the semi-continuous dyeing of fabric and knit fabric of cellulosic fibers with reactive dyes, with the steps

Order of dyeing liquor on the finished product (2); Winding up the padded goods (5); - lingering of the padded goods (5);

Unwinding of the goods (5); Washing the goods (5); Drying the product (5), characterized in that the padded product (5) is heated to an elevated temperature after the application of the dyeing liquor to the finished product (2).

2. The method according to claim 1, characterized in that the goods (5) after the order of the dyeing liquor is heated to an elevated temperature of about 45 ° C.

3. The method according to claim 1 or 2, characterized in that the liquor is cooled before and / or during the job.

4. The method according to any one of claims 1 to 3, characterized in that the goods (5) is provided after winding with an air-impermeable envelope.

5. The method according to any one of claims 1 to 4, characterized in that the goods after winding a room (10) is supplied.

6. The method according to any one of claims 1 to 5, characterized that the product (5) is held after winding at an elevated temperature.

7. The method according to claim 6, characterized in that the goods roll (8) is rotated during holding at the elevated temperature about the winding axis.

8. The method according to any one of claims 5 to 7, characterized in that the goods roll (8) is continuously displaced by the space (10).

9. Plant (100) for the application of the method according to one of claims 1 to 8, with an applicator device (4) for applying the dye liquor to the goods, with a winding station (7) for winding the goods (5) after the order of the dyeing liquor to a goods roll (8), characterized in that a heating device (6) for heating the goods (5) to an elevated temperature before winding the goods to the goods roll (8) is provided.

10. Plant according to claim 9, characterized in that a cooling device is provided for cooling the liquor before and / or during the job.

11. Plant according to claim 9 or 10, characterized in that a space (10) is provided, in which the goods roll (8) can be introduced.

12. Plant according to claim 11, characterized in that the space (10) comprises a heating device (12), by means of which the goods winding

(8) can be maintained at the elevated temperature.

13. Plant according to claim 11 or 12, characterized in that a conveying device is provided, by means of which the goods roll (5) continuously or discontinuously through the space (10) is conveyable and rotatable about the winding axis.