GB1595144A - Processing of cloth - Google Patents

Description

(54) IMPROVEMENTS IN OR RELATING TO THE PROCESSING OF CLOTH (71) We, SANDO IRON WORKS CO. LTD., a Japanese company, of No. 4-45, Usu, Wakayama-shi, Wakayama-ken, Japan, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement:- This invention relates to a method of and apparatus for processing a cloth under conditions of wet heat within a high pressure steamer.

It is known to subject a cloth to scouring, bleaching or dyeing treatments in a high temperature and high pressure steamer, in which a high pressure wet heat of about 1600C is maintained. Under such conditions, scouring, bleaching or dyeing treatments can be done at high speeds within a relatively short period of time, and many patent applications have been filed therefor for such methods and apparatus for performing them.

The steamer may be arranged to allow continuous feeding of cloth therethrough whilst the hot pressurised atmosphere is maintained therewithin. It has already been proposed for the desizing, scouring and bleaching of a cloth to impregnate the cloth with caustic soda solution, whereafter the cloth is desized and scoured by processing under the conditions of wet heat at about 1600C in the steamer, whereafter the processed cloth is impregnated with hydrogen peroxide solution for further processing under conditions of wet heat at about 1200C in another steamer for bleaching the cloth. In such a method, two high pressure steamers have to be used for the continuous desizing, scouring and bleaching of a cloth, thus there are the disadvantages that equipment costs are high, as well as the amount of factory space for the installation.

It is found that adjustment of the wet heat conditions in one steamer for both operations does not give satisfactory results. That is, hydrogen peroxide cannot withstand temperatures as high as 1600C, but caustic soda solution will have only a very slow and poor reactivity at a temperature as low as 120 C and a temperature higher than 120 C is required for reasonable operation.

Also, when different kinds of fibres are to be dyed simultaneously using for example disperse dyes and reactive dyes, the temperatures which the dyes can withstand are different. Disperse dyes can withstand a temperature of 160"C but a alkali for fixing reactive dyes will only function at a temperature of typically below 1200C.

Therefore, it has been found to be impossible to effect dying of mixed fibre cloths with different dyes such as disperse eyes and reactive dyes simultaneously within a steamer having a uniform temperature therewithin.

According to one aspect of this invention, there is provided a method of continuously processing cloth within a steamer vessel under conditions of wet heat with processing liquids to be used at different processing temperatures, the steamer vessel being divided into two chambers by means of a partition, in which method a relatively high temperature wet heat is maintained in one chamber and a relatively low temperature wet heat is maintained in the other chamber, and cloth is fed continuously through the steamer vessel for processing therewithin, the cloth initially being fed into the one chamber and then into the other chamber without leaving the steamer vessel and whilst being fed through the other chamber, the cloth is impregnated with a treatment liquid.

The partition may be arranged as a separate tank within the one chamber, with cloth inlet and outlet openings, so that the cloth can be fed back into the one chamber from the tank before leaving the steamer vessel.

In the case of a dyeing process, the cloth can be impregnated with disperse dye and reactive dye outside the steamer vessel, for instance by being passed through a tank containing the dyes, and after processing of the disperse dye in the one chamber, the cloth is fed into the other chamber and there impregnated with a alkali to fix the ractive dye. Such a process is especially useful with a mixed fibre cloth, such as a polyester/cotton cloth.

According to another aspect of this invention, there is provided apparatus for continuously processing cloth, which apparatus comprises a steamer vessel having a cloth inlet and a cloth outlet, sealing mechanisms being arranged over the inlet and outlet to allow the continuous passage of cloth therethrough whilst substantially maintaining the atmosphere in the steamer vessel, there being a partition within the steamer vessel to divide the vessel into a relatively high temperature wet heat chamber and a realtively low temperature wet heat chamber, and a sealing mechanism arranged on an opening through the partition to allow the continuous passage of cloth therethrough from one chamber to the other, there being a liquid bath arranged within the other chamber and through which the cloth passes after entering the other chamber, whereby cloth may first be processed in one chamber and then in the other utilising treatment liquid for the time being contained in the liquid bath.

Preferably, the partition is made of a thermally-insulating material, so as to reduce the transfer of heat when in use, from the one chamber, at a relatively high temperature, to the other chamber at a relatively low temperature.

In one embodiment of this invention, the partition is formed to define a separate tank within the steamer vessel, there being a cloth inlet to and a cloth outlet from the tank, the cloth being fed into the tank from the one chamber, and after processing in the tank, the cloth is fed back into the one chamber before leaving the steamer vessel through the cloth outlet.

When the apparatus is to be used for a dyeing process, the liquid bath may contain an alkali, to fix reactive dyes impregnated on the cloth prior to the cloth entering the steamer vessel.

It will be understood from the foregoing that with the method and apparatus of this invention, cloth may continuously be processed with treatments such as desizing, scouring, bleaching or multi-colour dyeing with different kinds of dyes, in one high pressure steamer. In this way, a reduction in equipment cost and installation area, as well as a saving of heat energy can be achieved.

By way of illustration of this invention, certain specific embodiments thereof will now be described, reference being made to the accompanying drawings, in which: Figure 1 is a schematic drawing of a first example of apparatus constructed in accordance with this invention; Figure 2 is a schematic drawing of a second example of such apparatus; Figure 3 is a longitudinal sectional view of a third example of apparatus constructed in accordance with this invention; and Figure 4 is a transverse sectional view of the apparatus shown in Figure 3.

Figure 1 shows an example of apparatus of this invention, for the desizing, scouring and bleaching of a cloth. A high pressure steamer vessel 1 is fitted with an inlet sealing mechanism 2 and an outlet sealing mechanism 3 at a cloth inlet to and a cloth outlet from the vessel 1, which mechanisms are arranged to allow the continuous feeding of cloth through the vessel 1 whilst a wet heat atmosphere is maintained therewithin. A bulkhead 4 having heat insulation properties is provided within the vessel 1, the portion of the vessel towards the cloth inlet from the bulkhead 4 being a relatively high temperature wet heat chamber 5, while the portion of the vessel towards the cloth outlet from the bulkhead 4 being a relatively low temperature wet heat chamber.A cloth passage 8 which is sealed by a pair of rubber sealing rolls 7 is provided through the bulkhead 4 so that cloth may be passed from one chamber to the other whilst the different temperatures are maintained therein.

Also within the vessel 1, guide rolls 9 are disposed to define a zig-zag path for cloth being transported through the vessel, there being dancer rolls 10 to regulate the tension of the cloth being transported. Drip protection plates 11 are provided one within each of the high temperature wet heat chamber 5 and the low temperature wet heat chamber 6, to protect the cloth from condensation drips. A liquid tank 12 is disposed in the path of the cloth in the chamber 6, adjacent the bulkhead 4, to supply hydrogen peroxide solution to the cloth. In addition, a water tank 13 is arranged further along the cloth path in the chamber 6, in which water may be contained if required.

The above described apparatus functions as follows.

Initially, the temperatures within the chambers are adjusted so that the temperature in the high temperature wet heat chamber is about 1600C while that within the low temperature wet heat chamber is about 1200C. Cloth is fed through the vessel from the inlet to the outlet, and desizing and scouring of the cloth are done by impregnating the same with caustic soda liquid either before the cloth is fed through the inlet sealing mechanism 2 of the steamer vessel 1, or just after the cloth has passed through the sealing mechanism, and processing the cloth with wet heat at about 1600C in the relatively high temperature wet heat chamber 5.

The cloth, having had the desizing and scouring process performed, is immediately fed into the relatively low temperature wet heat chamber 6.

As soon as the cloth enters the low temperature wet heat chamber 6, it is fed into the tank 12, wherein the cloth is impregnated with hydrogen peroxide solution. The cloth thus impregnated with hydrogen peroxide solution is processed under wet heat of about 1200C or below within the relatively low temperature wet heat chamber 6. In this way, effective bleaching is performed, without the hydrogen peroxide solution being spoilt.

The embodiment of Figure 2 will now be described, this embodiment being for the continuous dyeing of different kinds of fibres of a cloth 15, for instance consisting of 50% polyester fibre and 50% cotton fibre.

Disperse dyes are used for polyester fibres and reactive dyes are used for cotton fibres, but since the heat resistant temperatures and reaction temperatures of disperse dyes and of reactive eyes (or of alkalis which fix reactive dyes) are different, effective processing cannot be obtained with uniform exhaustion of the chamicals if the cloth is processed under a uniform temperature within a single high pressure steamer.

In this embodiment, a high pressure steamer body 16 is divided into a relatively high temperature we heat chamber 17 in which a temperature of about 1600C is maintained and a relatively low temperature wet heat chamber 18 in which a temperature of about 120"C is maintained, as in the preceding example. A sealing mechanism 19 is provided on a partition between the two chambers 17 and 18 so that the cloth 15 can be passed continusouly from chamber 17 to chamber 18. An inlet sealing mechanism 20 is arranged over the inlet opening to the high temperature wet heat chamber 17, and an outlet sealing mechanism 21 is arranged over the outlet opening from the low temperature wet heat chamber 18, these mechanism allowing continuous transfer of cloth therethrough.Liquid tanks, such as tank 22, are disposed in chamber 18, the structure of these being similar to that of the preceding example, and these will not therefore be explained again. Following the outlet sealing mechanism, a water tank 23 is arranged, through which the cloth is guided to pass.

The operation of the above embodiment will now be described. The cloth is impregnated with the required disperse and reactive dyes by being passed through a liquid tank (not shown in the drawing), which contains the two kinds of dyes. Then the cloth is fed into the high temperature wet heat chamber 17 through mechanism 20, the cloth being subjected there to wet heat at about 160"C, and the disperse dyes will be exhausted only on the polyester fibre. Then the cloth is fed into the low temperature wet heat chamber 18 through the sealing mechanism 19 and is impregnated with a reducing agent contained in the liquid tank 22. Once treated, under wet heat of about 120"C exhaustion of the reactive dyes will be performed on the cotton fibres.The cloth, after exhaustion of both kinds of dye, is taken out of the high pressure steamer body through mechanism 21 and is cleaned in the water washing tank 23 before being sent to the next processing step.

The third example of apparatus of this invention will now be described referring to Figures 3 and 4. Parts similar to those of Figure 1 are given like reference characters and will not be described in detail again.

Within the steamer vessel 1, there is provided a closed liquid tank 24, made of a heat insulating material, and arranged so that cloth passes therethrough as the cloth is transported through the vessel 1. The tank 24 is disposed beyond the half-way point of the path for cloth passing through the vessel 1, as shown. Liquid within the tank 24 is maintained at a relatively low temperature and is protected from the relatively high temperature of typically 1600C in the steamer. Heat insulating sealing rolls 25 are provided over the cloth inlet to and cloth outlet from the liquid tank 24. A liquid exhaust pipe 26 and a liquid supply pipe 27, communicating to outside the steamer vessel 1 are connected to the liquid tank 24, the pipe 26 supplying liquid drained from the tank 24 to a recovery tank 28.Fresh liquid can be added to the recovery tank 28 from a liquid replenishing pipe 29, or the liquid can from there be led to a heat exchanger (not shown in the drawing) for cooling. Liquid can be pumped as required froni the recovery tank 28 by a pump 30 through pipe 27 to the liquid tank 24 inside the steamer vessel.

As mentioned above, the polyester fibre in a cloth has to be dyed with disperse dyes while the cotton fibre in the same cloth has to be dyed with reactive dyes. The cloth is impregnated with both kinds of dyes in a single bath liquid tank (not shown in the drawing) located outside the steamer vessel and in which the disperse dyes and reactive dyes are mixed. From there, the cloth is fed into the steamer vessel 1 and is processed under the wet heat within the steamer vessel. Exhaustion of the disperse dyes thus occurs on the polyester fibre. After exhaustion of the disperse dyes, the cloth is guided into the liquid tank 24 which contains a reducing agent, so that impregnation of the cloth occurs to fix the reactive dyes, and exhaustion of the reactive dyes will occur on the cotton fibre.Since the alkali which fixes the reactive dyes is maintained at a relatively low temperature, typically below 120"C, by the heat-insulated structure of the liquid tank 24, effective exhaustion of the reactive dyes can be secured without spoiling the reducing agent by the high temperature within the major part of the steamer vessel.

As has been explained above, if a cloth is to be processed under conditions of high pressure wet heat using processing liquids which have different processing temperatures or different heat resistant temperatures, a single high pressure steamer vessel can be used by dividing the vessel into relatively high temperature and relatively low temprature wet heat chambers, in accordance with the invention. When in use, each of the different processes can be performed continuously at wet heat temperature suitable for each processing agent respectively. Thus the invention has the advantage of allowing effective high pressure wet heat processing without spoiling the processing agents.Also, in the second example of the invention, the structure is such as to allow dismantling of the high temperature wet heat chamber 17 from the low temperature wet heat chamber 18, and this permits repairs, maintenance and inspection to be effected easily.

WHAT WE CLAIM IS: 1. A method of continuously processing cloth within a steamer vessel under conditions of wet heat with processing liquids to be used at different processing temperatures, the steamer vessel being divided into two chambers by means of a partition, in which method a relatively high temperature wet heat is maintained in one chamber and a relatively low temperature wet heat is maintained in the other chamber, and cloth is fed continuously through the steamer vessel for processing therewithin, the cloth initially being fed into the one chamber and then into the other chamber without leaving the steamer vessel and whilst being fed through the other chamber, the cloth is impregnated with a treatment liquid.

2. A method as claimed in claim 1, wherein thecloth is fed back into the one chamber from the other chamber before leaving the steamer vessel.

3. A method as claimed in claim I or claim 2, wherein the cloth is impregnated with disperse dye and reactive dye outside the steamer vessel, and after processing of the disperse dyes in the one chamber, the cloth is fed into the other chamber and impregnated with an alkali to fix the reactive dye in the other chamber.

4. A method of continuously processing cloth substantially as hereinbefore described, with reference to the accompnaying drawings.

5. Apparatus for continuously processing cloth, which appartus comprises a steamer vessel having a cloth inlet and a cloth outlet, sealing mechanisms being arranged over the inlet and outlet to allow the continuous passage of cloth therethorugh whislt substantially maintaining the atmosphere in the steamer vessel, there being a partition within the steamer vessel to divide the vessel into a relatively high temperature wet heat chamber and a relatively low temperature wet heat chamber, and a sealing mechanism arranged on an opening through the partition to allow the continuous passage of cloth therethourgh from one chamber to the other, there being a liquid bath arranged within the other chamber and through which the cloth passes after entering the other chamber, whereby cloth may first be processed in one chamber and then in the other, utilising treatment liquid for the time being contained in the liquid bath.

6. Apparatus as claimed in claim 5, wherein the partition is made of a thermallyinsulating material.

7. Apparatus as claimed in claim 5 or claim 6, wherein the partition is formed to define a separate tank within the steamer vessel, there being a cloth inlet to and a cloth outlet from the tank, the cloth being fed into the tank from the one chamber, and after processing in the tank, the cloth is fed back into the one chamber before leaving the steamer vessel through the cloth outlet.

8. Apparatus for the continuous treatment of cloth under conditions of wet heat, substantially as hereinbefore described with reference to and as illustrated in Figure 1 or in Figure 2 or in Figures 3 and 4 of the accompanying drawings.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims (8)

**WARNING** start of CLMS field may overlap end of DESC **. guided into the liquid tank 24 which contains a reducing agent, so that impregnation of the cloth occurs to fix the reactive dyes, and exhaustion of the reactive dyes will occur on the cotton fibre. Since the alkali which fixes the reactive dyes is maintained at a relatively low temperature, typically below 120"C, by the heat-insulated structure of the liquid tank 24, effective exhaustion of the reactive dyes can be secured without spoiling the reducing agent by the high temperature within the major part of the steamer vessel. As has been explained above, if a cloth is to be processed under conditions of high pressure wet heat using processing liquids which have different processing temperatures or different heat resistant temperatures, a single high pressure steamer vessel can be used by dividing the vessel into relatively high temperature and relatively low temprature wet heat chambers, in accordance with the invention. When in use, each of the different processes can be performed continuously at wet heat temperature suitable for each processing agent respectively. Thus the invention has the advantage of allowing effective high pressure wet heat processing without spoiling the processing agents.Also, in the second example of the invention, the structure is such as to allow dismantling of the high temperature wet heat chamber 17 from the low temperature wet heat chamber 18, and this permits repairs, maintenance and inspection to be effected easily. WHAT WE CLAIM IS:

1. A method of continuously processing cloth within a steamer vessel under conditions of wet heat with processing liquids to be used at different processing temperatures, the steamer vessel being divided into two chambers by means of a partition, in which method a relatively high temperature wet heat is maintained in one chamber and a relatively low temperature wet heat is maintained in the other chamber, and cloth is fed continuously through the steamer vessel for processing therewithin, the cloth initially being fed into the one chamber and then into the other chamber without leaving the steamer vessel and whilst being fed through the other chamber, the cloth is impregnated with a treatment liquid.

2. A method as claimed in claim 1, wherein thecloth is fed back into the one chamber from the other chamber before leaving the steamer vessel.

3. A method as claimed in claim I or claim 2, wherein the cloth is impregnated with disperse dye and reactive dye outside the steamer vessel, and after processing of the disperse dyes in the one chamber, the cloth is fed into the other chamber and impregnated with an alkali to fix the reactive dye in the other chamber.

4. A method of continuously processing cloth substantially as hereinbefore described, with reference to the accompnaying drawings.

5. Apparatus for continuously processing cloth, which appartus comprises a steamer vessel having a cloth inlet and a cloth outlet, sealing mechanisms being arranged over the inlet and outlet to allow the continuous passage of cloth therethorugh whislt substantially maintaining the atmosphere in the steamer vessel, there being a partition within the steamer vessel to divide the vessel into a relatively high temperature wet heat chamber and a relatively low temperature wet heat chamber, and a sealing mechanism arranged on an opening through the partition to allow the continuous passage of cloth therethourgh from one chamber to the other, there being a liquid bath arranged within the other chamber and through which the cloth passes after entering the other chamber, whereby cloth may first be processed in one chamber and then in the other, utilising treatment liquid for the time being contained in the liquid bath.

6. Apparatus as claimed in claim 5, wherein the partition is made of a thermallyinsulating material.

7. Apparatus as claimed in claim 5 or claim 6, wherein the partition is formed to define a separate tank within the steamer vessel, there being a cloth inlet to and a cloth outlet from the tank, the cloth being fed into the tank from the one chamber, and after processing in the tank, the cloth is fed back into the one chamber before leaving the steamer vessel through the cloth outlet.

8. Apparatus for the continuous treatment of cloth under conditions of wet heat, substantially as hereinbefore described with reference to and as illustrated in Figure 1 or in Figure 2 or in Figures 3 and 4 of the accompanying drawings.