EP1746191A2 - Method and device for the continuous steam treatment of a textile fabric to fix reactive dyestuffs on natural fibres - Google Patents

Abstract

The device has a transport device guiding textile fabric (1) horizontally through treatment chambers (12), and a steam-proof housing (10) enclosing all chambers. Each chamber is provided with a fan (14) and nozzle boxes (15) that are arranged above and below the textile fabric. Conveyor belt of the transport device is designed as filter belt, where the extent of opening of the filter belt amount to 50 to 90 percent.

Description

The invention relates to a device for continuous treatment of a textile web with steam for fixing reactive dye on native fibers according to the preamble of claim 1

For fixing reactive dye on native fibers, such as cotton or cellulose, it is known to first dry the wet web applied with reactive dye and then reacting the dye with the fibers of the web. For this purpose, aids such as urea, which are added to the reactive dye needed. The auxiliaries keep the reactive dye in solution during drying and evaporate on fixing. This applies to dyeing as well as printing by the reactive dye.

For fixing of reactive dye applied by printing, it is known to treat the dried web with saturated steam. A corresponding device with a steam chamber is in the EP 0607 762 B described. To reduce urea consumption, this device has a pre-wetting chamber.

A reduction of the amount of urea is, as in the DE 43 03 129 C2 described, also made possible by spraying the printed and dried goods immediately before entering the Hänschleleifendämpfer with water. These fixation methods in the hanging loop damper require an average steaming time of 10 to 15 minutes. The goods content is generally 80 to 490 m, resulting in a goods speed of 5 to 50 m / min.

In the hanging loop damper, the fixation of the reactive dye is usually carried out with saturated steam at about atmospheric pressure, that is, in a saturated steam atmosphere. A hanging loop damper with a product content of at least 80 m is not economically viable for smaller quantities to be dyed (smaller quantities).

Another is from the DE 23 10 195 C2 known. This damper has a treatment chamber and a transport device with an at least partially horizontal goods guide by means of a conveyor belt. The treatment chamber is designed as a downwardly open hood. This can precipitate entrained air from the downwardly open steam room, so that there is always a pure steam atmosphere available. A fixation of a dry web in this steam atmosphere, which is also a pure saturated steam atmosphere, is not possible without urea. Disadvantage of this damper is that due to the above-mentioned steaming time in saturated steam atmosphere of 10 to 15 minutes in continuous operation only low speeds of goods can be driven. Higher speeds would only be possible with large lengths of the damper with correspondingly high investment and operating costs. Also, this damper is not economical for smaller quantities to be dyed.

Another disadvantage of the above-mentioned method is that the web is first dried after exposure to reactive dye dissolved in water and only then the reactive dye is fixed to the fibers. The two stages of drying and fixing require two treatment devices. During printing, a printing mansard is usually used for drying and for fixing one of the abovementioned damping devices,

At a special, from the DE 196 33 101 known printing method, the web is moistened, wet printed and steamed in the wet state without intermediate drying. The damping is in one Saturated steam atmosphere for 1.0 to 20 min at 96 to 105 ° C carried out. Also in this process, when reactive dye is used to print cotton, urea is used in the usual amount.

Another special printing method in which the web first moistened, printed on the wet web and then subjected to an evaporative Thermosolfixierungsprozess is from the WO 96/28604 known. The evaporative thermosol fixation process takes place under saturated steam at temperatures of 90, 150 and 170 degrees. He therefore requires a pressure-tight fixing device, which is usually suitable only for a discontinuous operation.

The object of the invention is to develop a device for the continuous treatment of a textile web with steam for fixing reactive dye on native fibers according to the preamble of claim 1, which is economically usable for smaller Metragen to develop. In particular, the steam treatment should be more effective and thus faster to carry out. It should also be suitable for fixing printed webs.

The object is solved by the characterizing features of claim 1.

In a process for the continuous treatment of a textile web with steam, in which a reactive dye acted upon wet web of native fibers is contacted with steam, hereinafter also called steaming, fixing or dye fixing, the steam in the form of superheated steam, the is used as superheated steam at about atmospheric pressure. The superheated steam consists of at least 80% by volume, preferably 95 to 100% by volume (pure superheated steam) of water vapor.

The superheated steam has a temperature of 130 to 230 ° C, in particular from 160 to 230 ° C, on.

In addition to the high web temperature, which is 100 ° C with pure superheated steam, allows the additional temperature difference between the superheated steam and the web of 30, in particular 60, to 130 ° C, an acceleration of the reaction of the reactive dye with the native fibers. This leads, compared to a Flxierbehandlung in saturated steam atmosphere, to lower heating and fixing times, correspondingly lower residence times in a steam treatment apparatus, thus enabling devices that are economically viable for smaller Metragen.

Essential for the process is also that the moist web is dried during the steam treatment by the use of superheated steam. It has been found that drying the web during the fixing treatment leads to an acceleration of the reaction of the reactive dye with the native fibers. This results in a further reduction of the fixing time.

In the treatment method according to the invention can be dispensed with the use of urea for most reactive dyes. This applies to the dyeing of textile webs, in which the reactive dyed webs have a moisture content of, for example, 40 to 80%. This also applies to the printing of textile webs, in which the printed with reactive dye webs have a moisture content of, for example, 10 to 40%.

Surprisingly, this treatment process with superheated steam and with increased drying results in good fixing results, namely good color yield and good color quality, which correspond to the results of the prior art.

The web is at least partially transported horizontally through at least one treatment chamber during the steam treatment. A horizontal web guide allows gentle transport of the reactive dye acted upon, moist web. In contrast, there is the risk of color gradients in a roll gear damper or in a hanging loop damper by the vertical web guide. The use of a horizontal web guide, which requires a large volume of construction in a saturated steam atmosphere based on the product content, can also be used for smaller quantities in connection with the effective steam treatment with superheated steam.

The superheated steam is inflated in the treatment chambers through nozzle boxes arranged above and below the material web onto the material web. Preferably, the superheated steam is conducted in the recirculation method. Unlike the one from the DE 23 10 195 C2 known, self-adjusting saturated steam atmosphere without appreciable flow velocity is therefore the web with hot steam sprayed. The spraying allows a higher rate of exchange of the treatment vapor on the surface of the web and thereby a greater energy input per time than a stationary Dampfatmoshäre. By spraying the steam treatment is further improved and the applicability of the method according to the invention for small Metragen improved.

The use of superheated steam has the advantage of a lower risk of condensation in the recirculation system compared to saturated steam in the case of spraying via a recirculation system,

When using the method according to the invention for printing textile webs, the moisture content of the printed web is adjusted to 10 to 40%, in particular 15 to 25% before the steam treatment and the web during the steam treatment to a residual moisture content of 1 to 10%, in particular 3 to 7% is dried. Surprisingly, it has been found that in the process for a printed web optimal Fixing results with a residual moisture of the web smaller than the equilibrium moisture content can be achieved according to claim 2. The equilibrium moisture content is under normal conditions about 10% moisture based on the weight of the web in cellulose and about 8% moisture in cotton, a regulation of the residual moisture of the web in the treatment chambers is not necessary.

The residence time of the web in the treatment chambers may be 5 to 60 seconds, preferably 10 to 20 seconds. This time is sufficient for drying and complete fixation with good color yield and allows a device of small size.

By transporting the fabric web by means of a wire belt on the one hand, a transport of the web through the treatment chamber without touching the possibly printed surfaces and on the other hand allows a steam supply from above and from below onto the web.

An apparatus according to claim 1 is suitable for carrying out this method. A steam-tight housing enclosing all treatment chambers allows the use of superheated steam. With the help of the recirculation devices with at least one circulating air fan and nozzle cheeses arranged above and below the material web, the steam treatment with superheated steam can also be made effective in the gentle, horizontal material web guidance.

This device is therefore particularly suitable for fixing small coins.

The transport of the web through a belt designed as a belt conveyor allows for a non-contact transport of the printed surface of the web steam delivery from the top and bottom of the web. The

Device is therefore particularly suitable for color fixing printed webs.

A large opening degree of the screen belt of 50 to 90% allows a large contact surface of the web to superheated steam. This leads to a high exchange rate and thus to a more effective steam treatment.

To arrange the guide rollers for the trained as a wire belt conveyor belt according to claim 2 outside of the vapor-tight housing, simplifies the construction of the device. Only slots for the entry and exit of the conveyor belt must be provided.

A return of the conveyor belt below the housing according to claim 3 requires only one inlet and one outlet slot for the conveyor belt and allows the arrangement of a clamping system and a drive for the conveyor belt outside of the vapor-tight housing. This simplifies the construction of the device.

A according to claim 4 at an acute angle to the vertical through the entrance lock extending guide belt, which may be formed by the conveyor belt itself or another band, allows deflections of the web by angles> 90 °. As a result, the risk of impairment of the printed image due to excessive deflections of the web, as they might occur at a deflection of 90 °, reduced. The acute angle is preferably 30 to 60 °.

A supply belt projecting in the vicinity of the conveyor belt running through the treatment chambers according to claim 5 simplifies the supply of the beginning of a new web to the conveyor belt.

A feed belt extending through the entrance gate according to claim 6 is particularly suitable for devices having a conveyor belt returning through the treatment chamber.

According to claim 7, the device according to the invention in front of and behind the housing in each case a lock on. The locks extend from the floor to the transport plane of the web and are divided into a lower, downwardly open pre-chamber and a main chamber arranged above. Intake channels or suction boxes can be connected to the antechambers. Compared to those from the DE-A 195 46 344 known inlet and outlet slots with suction boxes is prevented by the separate locks with pre-chamber and Absaugeinrlchtungen the penetration of air and thus condensation of steam to water safer. One from the DE 198 58 839 Known lock in which steam is blown onto the web in front of the inlet slot of the housing, is less suitable for fixing dye because of the risk of color gradients.

The invention will be further explained with reference to two examples schematically illustrated in the drawing. Figure 1 shows a system for printing a textile web with a device for fixing the ink of the first example according to the invention and Figure 2 shows this device with reference to a schematic cross section. A device according to the invention for fixing the color of the second example is likewise illustrated with reference to a schematic cross section in FIG.

• Eine Anlage zum Bedrucken einer textilen Warenbahn 1 aus nativen Fasern, zum Beispiel aus Baumwolle oder Zellulose, mit Reaktivfarbstoff weist in Transportrichtung hintereinander angeordnet einen Warenspeicher 2, eine Zufuhrvorrichtung 3, eine Druckvorrichtung 40, eine Vorrichtung zum Farbfixieren 6, eine weitere Zufuhrvorrichtung 7 und einen weiteren Warenspeicher 8 auf. In diesem Beispiel sind der vordere Warenspeicher 2 als Wickler, die vordere Zufuhrvorrichtung 3 als Galgen, die hintere Zufuhrvorrichtung 7 als Abtafler und der hintere Warenspeicher 8 als Behälter ausgebildet. Die Druckvorrichtung 40 ist als Rotationsdruckmaschine ausgebildet. Alternativ kann auch eine andere Druckmaschine, wie zum Beispiel eine Flachbettdruckmaschine oder eine Ink-Jet-Druckmaschine, eingesetzt sein.

Example 1 (Figure 1 and Figure 2):

• A plant for printing a textile web 1 of native fibers, for example of cotton or cellulose, with reactive dye has arranged in the transport direction one behind the other a goods storage 2, a feed device 3, a printing device 40, a device for ink fixation 6, another supply device 7 and a another goods storage 8. In this example, the front goods storage 2 as winder, the front Feed device 3 as a gallows, the rear feed device 7 as Abtafler and the rear goods storage 8 formed as a container. The printing device 40 is designed as a rotary printing machine. Alternatively, another printing machine, such as a flatbed printing machine or an inkjet printing machine, may be used.

The device 6 for color fixing has an entrance lock 9, a vapor-tight, heat-insulated housing 10 and an exit lock 11. The housing 10 comprises one or more, preferably one to four, modularly juxtaposed treatment chambers 12; that is, the interior of the housing 10 is divided by the treatment chamber 12 in one or more consecutively arranged fields. The housing 10 is not subdivided and comprises all treatment chambers, in this example a treatment chamber 12.

In each treatment chamber 12 is a recirculation device, that is a device for guiding superheated steam in a cycle, also called recirculation method, arranged with at least one Umluftventilatar 14, at least one heating device not shown in the drawing and with nozzle boxes 15 with targeting the web 1 nozzle openings , The nozzle boxes 15 are arranged above and below the web 1 and extend transversely across the web 1. In a treatment chamber 12, one or more upper and lower nozzle boxes 15 may be arranged one behind the other. In this example, the treatment chamber 12 is provided with four upper and four lower nozzle boxes 15 and two circulating fans 14. Each of the recirculation fans 14 is associated with two upper and two lower nozzle boxes 15. The upper and lower nozzle boxes 15 may be arranged opposite to each other or offset from each other. The nozzle openings of the nozzle boxes 15 are preferably formed as slots.

The transport device has a trained as a sieve belt 41, circulating conveyor belt, by two upper guide rollers 42, 43 with its upper Run through the treatment chamber 12 and through two lower guide rollers 44, 45 with its lower run under the treatment chamber 12 and below the housing 10 is guided. The upper front guide roller 42 is completely in the entrance lock 9 and the upper rear guide roller 43 completely in the exit lock 11. Their arrangement is such that the web 1 in the treatment chamber 12 is flat and horizontal, that is in a horizontal transport plane, out , One of the lower guide rollers 44, 45 is connected to a drive, not shown.

The transport device further comprises a, not shown, conventional tensioning device, through which the screen belt 41 is stretched, and optionally not shown support devices in the treatment chamber 12. The support devices may be formed by longitudinal slide rails attached to the sides on the nozzle boxes 15 or by support rollers mounted between the nozzle boxes 15.

The screen belt 41 has an open area of at least 50% to a maximum of 90%. It consists in this example of a metal link belt with an open area of 80% and has chain links on its sides. Accordingly, the guide rollers 42, 43, 44 and 45 on their sides on gears. Alternatively, the screen belt 41 may be formed as a perforated metal strip or as a glass cloth tape.

The housing 10 has on a front wall 26 an inlet slot 27 and on a rear wall 28 an outlet slot 29, through which the web 1 is guided in the housing 10 and out of it.

The entrance lock 9 has a parallel to the front wall 26 extending, in the vicinity of a lower edge 30 to above the inlet slot 27 extending front plate 31, a ceiling plate 32 and two side plates, not shown. The sheets 31, 32 of the entrance lock 9 are vapor-tight with each other and connected to the front wall 26. The entrance lock 9 is characterized by intermediate plates 33, 34 extending from the front panel 31 and the front wall 26 into the interior of the entrance lock 9 and between them leave a gap 35 for the web 1 and possibly a conveyor belt, divided into an upper main chamber 38 and a lower prechamber 37. The pre-chamber 37 is open at the bottom. To the antechamber 37, a suction device, in this example connected to a fan, not shown suction channel 38 is connected. Optionally located, as in this example, suction boxes 39, to which the suction channel 38 is connected, in the antechamber 37. The guide roller 44 of the transport device is located directly below the prechamber 37 and the guide roller 42 in front of the inlet slot 27th

The exit lock 11 is constructed analogously to the entrance lock 9. The guide rollers 43, 45 are arranged analogously to those of the entrance lock 9. The transport device also has a guide roller 46 arranged behind the guide roller 45 for deflecting the web 1 and for separating from the wire 41 and a feed belt 47 for feeding the web 1 to the device 6 on. The feed belt 47 guided around two rollers 48, 49 extends horizontally in this example and extends below the pre-chamber 37 of the inlet lock 9.

For printing, the web 1 is withdrawn from the goods storage 2 via the feed device 3 designed as a gallows and supplied to the device 6 for color fixing by the printing device 40 designed as a rotary printing press.

The web 1 is transported over the feed belt 47 of the transport device to below the antechamber 37 of the entrance lock 9. There, the screen belt 41 takes over the transport from below through the prechamber 37, through the gap 35 in the main chamber 36 to the guide roller 42 around, through the inlet slot 37 and through the treatment chamber 12. For this, the web 1, possibly automatically, to the screen belt 41 is clamped. The web 1 leaves the Device 6 through the exit slot 29 and the exit lock 11. It is supplied via the designed as Abtafler supply device 7 designed as a container goods storage 8. The web speed is, for example, 40 m / min.

In the printing device 40, the web 1 is applied with printing paste. The moist web 1 is, while it is being transported through the treatment chamber 12 of the device 6, applied via the above and below the web 1 arranged nozzle boxes 15 directed to the web 1 nozzle openings with superheated steam. The nozzle pressure is 200 to 1000 PA and the heat transfer capacity about 240 W / m ² .

The temperature of the superheated steam is 130, in particular 160, to 230 ° C and the residence time of the web 1 in the treatment chamber 12 5 to 60 seconds, preferably 10 to 20 seconds. The residual moisture of the web 1 when leaving the housing 10 during printing is less than the equilibrium moisture content under normal conditions, that is, it is less than 10%. In the treatment chamber 12 and in the main chambers 36 of the inlet and outlet lock 9, 11 a slight overpressure is maintained. The steam content, preferably between 95 and 100% by volume, is maintained by varying the amount of superheated steam extracted via the suction channels 38 of the antechambers 37 of the inlet and outlet sheaths 9, 11. A regulation of a certain residual moisture of the web 1 is not necessary

Print example:

A web 1 of cotton (BG), which has been treated with printing paste of a reactive dye without urea and has a product weight of 80 g / m ² , is transported through the device 6 at a web speed of 40 m / min. The temperature of the pure hot steam is 180 ° C. The nozzle pressure at the nozzle openings of the nozzle boxes 15 is 700 PA. Even after a residence time of 5 seconds, the vast majority of the dye has reacts with the fibers of the web 1 and is fixed. After another 5 seconds, the web 1 is completely dried and the remaining part of the dye is fixed. The input moisture of about 20% is reduced in the device 6 to a value less than or about 5%. The total residence time in the device 6 is 10 seconds.

Example 2 (FIG. 3):

The color fixing apparatus 6 of Example 2 is the same as that of Example 1 except for the features described below.

Your housing 10 includes three treatment chambers 12, each treatment chamber 12 is provided with a circulating air fan 14 and an upper and a lower nozzle box 15.

Your transport device also has a designed as a sieve belt 51, circulating conveyor belt, which is guided in contrast to Example 1 by two guide rollers 52 and 53 with its upper and with its lower run through the treatment chambers 12; that is, the conveyor belt is returned through the treatment chambers 12. Also, the guide roller 52 is completely in the entrance lock 9 and the guide roller 53 completely in the exit lock 11. Their arrangement is also such that the web 1 is guided in a horizontal transport plane. The deflection roller 53 in the exit lock 11 is connected to a drive, not shown. In the exit lock 11 is also a clamping device, not shown, for the conveyor belt.

The transport device furthermore has support rollers 54 in the field impacts, that is to say in the regions in which the treatment chambers 12 abut one another.

The entrance lock 9 of this device 6 for color fixing runs at an acute angle to the vertical. For this purpose, the front plate 31 is arranged at this acute angle to the vertical and the side plates, not shown, are shaped accordingly. The outgoing of the front wall 26 intermediate plate 34 is extended according to the deflection of the front plate 31 and has at its front end to such a fold 55 that it ends with respect to the outgoing from the front plate 31 intermediate plate 33. Also, the outgoing from the front wall 26 nozzle box 39 is extended and folded accordingly.

The transport device has in this example a guide roller 56 at the exit of the exit lock 11 and a feed belt 57. The feed belt 57, which is guided around two rollers 58, 59, runs parallel to the front plate 31 and extends through the front chamber 37 and the main chamber 36 of the entrance lock 9; i.e. the supply belt 57 forms at an acute angle to the vertical, through the entrance lock 9 extending guide band. The gap 35 between the intermediate plates 33 and 34 and the distance between the suction boxes 39 is formed correspondingly wide. The upper roller 59 of the feed belt 58 is arranged slightly in front of and slightly above the deflection roller 52 and the roller 56 in front of the prechamber 37 of the entrance lock 9.

When printing the applied with printing paste, moist web 1 is transported via the feed belt 57 through the entrance lock 9, placed on the wire 51 from above and transported on the wire 51 through the treatment chambers 12 to the exit lock 11. From the exit lock 11, the web 1 is withdrawn via the guide roller 56.

LIST OF REFERENCE NUMBERS

1

web

2

goods storage

3

feeding apparatus

4

-

5

-

6

Device for color fixing

7

Feeding device (Abtafler)

8th

goods storage

9

entry lock

10

casing

11

exit lock

12

treatment chamber

13

-

14

circulation fan

15

nozzle box

16 to 25

-

26

front wall

27

inlet slot

28

behind wall

29

outlet slot

30

lower case edge

31

front plate

32

decking

33

intermediate plate

34

intermediate plate

35

gap

36

main chamber

37

antechamber

38

suction

39

suction box

40

printing device

41

screen belt

42

upper front deflecting roller

43

Upper rear deflecting roller

44

lower front guide roller

45

lower rear guide roller

46

guide roller

47

feed belt

48

roller

49

roller

50

-

51

screen belt

52

front deflecting roller

53

rear deflecting roller

54

supporting roll

55

fold

56

guide roller

57

feed belt

58

roller

59

roller

Claims (7)

Apparatus for the continuous treatment of a textile web (1) with steam, with at least one treatment chamber (12),
with a transport device (1) horizontally through the treatment chambers (12) leading with a vapor-tight, all treatment chambers (12) enclosing the housing (10), each treatment chamber (12) with at least one recirculation device with at least one recirculation fan (14) and above and below the web (1) arranged nozzle boxes (15) is provided, characterized by a
as a screen belt (41, 51) formed conveyor belt of the transport device, wherein the opening degree of the screen belt (41, 51) is 50 to 90%. Device according to claim 1, comprising an entrance lock (9) and an exit lock (11), characterized in that
the transport device for the conveyor belt has at least two deflecting rollers (42, 43, 44, 45, 52, 53), the deflecting rollers (42, 43, 44, 45, 52, 53) outside the housing (10) and at least upper deflecting rollers (42 , 43, 52, 53) are arranged completely in the entrance lock (9) and the exit lock (11). Apparatus according to claim 2, characterized in that the
Transport device next to the conveyor belt four guide rollers (42, 43, 44, 45), wherein the conveyor belt by two upper guide rollers (42, 43) through the treatment chambers (12) of the housing (10) and by two lower guide rollers (44,45) is guided below the housing (10). Device according to one of claims 1 to 3, characterized in that
the transport device has a guide strip running at an acute angle to the vertical through the entrance slash (9). Device according to one of claims 1 to 4, characterized by a front of the housing (10) arranged in the vicinity of the conveyor belt projecting supply belt (47, 57). Apparatus according to claim 5, wherein the conveyor belt passes through the
Treatment chambers (12) is returned, characterized in that the supply belt (57) through the entrance lock (9) extends. Device according to one of claims 1 to 6, in which the entrance lock (9) and the exit lock (11) are provided with suction devices, characterized in that the entrance lock (9) and the exit lock (11) from ground level to above a transport plane of the Web (1) extend, in its lower portion are open at the bottom and in each case in an upper main chamber (36) and in a near the bottom, lower suction connected to the prechamber (37) are divided.

Images