GB2079800A

GB2079800A - Continuous wet-heat treatment of cloth

Info

Publication number: GB2079800A
Application number: GB8121772A
Authority: GB
Original assignee: Sando Iron Works Co Ltd
Current assignee: Sando Iron Works Co Ltd
Priority date: 1980-07-16
Filing date: 1981-07-15
Publication date: 1982-01-27
Also published as: DE3127537A1; JPS594074Y2; JPS5727495U

Abstract

High pressure steamer for pre- treating or dyeing a cloth includes a pre-washing tank 8 within the steamer body and the cloth outlet has an outlet seal mechanism 5 provided with a slow cooling tank 52, the pre-washing tank 8 being supplied with washing water continuously from the outside of the steamer body by providing a water supply line whereby hot water overflowing at 11 from the slow cooling tank is passed via tank 9 by pump to to the pre-washing tank 8. <IMAGE>

Description

SPECIFICATION High pressure steamer for the continuous wet-heat treatment of cloth The present invention relates to a high pressure steamer for pretreating or dyeing a cloth by a wet-heat treatment at an elevated pressure.

In the pretreatment or dyeing of a long length of cloth produced commercially, the cloth conventionally has been soaked in, for example, a dye solution by immersing the cloth to be treated in a tank containing a dye solution and then the cloth has been subjected to a wet-heat treatment on a batch basis is a steamer at a temperature below 100,C. In such a conventional dyeing method, since the treatment is discontinuous a large amount of heat energy is consumed uneconomically and the degree of dyeing differs from batch to batch. Moreover and in particular, an uneconomically long time is required to fix the dye sufficiently to the cloth when the wet-heat treatment temperature is below 100 C.

The present Applicants have developed after a great deal of research over a long period of time a high pressure steamer with which a long length of cloth can be pretreated or dyed continuously in a relatively short time of, say, several seconds. This steamer, which has been used in practice produces a cloth which is in a swollen state after wet-heat treatment, and such a swollen cloth can be washed very effectively. Therefore, a high pressure steamer provided with a pre-washing tank in the vicinity of the outlet of the steamer body to which washing water is supplied continuously from the outside of the steamer body has also been developed by the present Applicants and used in practice.

However, the interior of a high pressure steamer body is usually maintained under wetheat conditions at a temperature of about 1 50,,C and the washing liquid to be supplied from outside to within the steamer body is usually at ambient temperature (e.g. about 20 C). This means that there is a large temperature difference between the washing liquid and the atmosphere in the steamer body so that when washing water at a low temperature is brought into the steamer body maintained under wet-heat conditions condensation of steam in the steamer body occurs. This condensation decreases the temperature and degree of wet-heat in the steamer body and a significant amount of heat energy must be supplied to maintain wet-heat conditions at a sufficiently high temperature within the steamer body.

We have now found, according to the present invention, that the above disadvantage can be avoided in a high pressure steamer provided with a pre-washing tank within the steamer body by supplying hot washing water from outside into the pre-washing tank, thus reducing or preventing the condensation of steam in the steamer body. The principle of the invention comprises the provision of a water supply line for supplying previously heated hot water overflowing from the slow cooling tank provided in the vicinity of the cloth outlet of the steamer body to the prewashing tank.

Accordingly, the present invention provides a high pressure steamer for the continuous wet-heat treatment of a cloth, which steamer comprises a steamer body including a prewashing tank therein and having a cloth inlet and a cloth outlet permitting cloth to be continuously passed through the steamer body, the cloth outlet having an outlet seal mechanism provided with a slow cooling tank, and the steamer including means to supply hot overflow water from the slow cooling tank to the pre-washing tank.

The invention also provides a method of continuously treating cloth, which method comprises subjecting the cloth to a wet-heat treatment at a temperature in excess of 1 00 C and at superatmospheric pressure, sufficient to support a saturated vapour as required, the cloth being passed in one step through a prewashing liquid under said conditions and subsequently through a cooling liquid, and cooling liquid which has been heated by the cloth being used to supply fresh pre-washing liquid.

By using the present invention the condensation of steam in the steamer body can be substantially prevented in a satisfactory manner, and the wet-heat treatment of a cloth can be performed under stable conditions to produce a uniform product. Moreover, since the waste hot water obtained in the slow cooling tank is utilized for supplying hot water to the pre-washing tank, heat energy is saved and water resources are conserved.

The invention will now be described by way of example with reference to the accompanying drawing which shows a diagrammatic section through a high pressure steamer according to the present invention.

Referring to the drawing, the steamer shown comprises a steamer body 1 having a cloth inlet 2 and a cloth outlet 3. The cloth inlet 2 and the cloth outlet 3 are provided respectively with an inlet seal mechanism 4 and an outlet seal mechanism 5 for allowing cloth to be passed through the steamer while maintaining the necessary conditions of high temperature and humidity in the steamer body 1 without leakage. The inlet side seal mechanism 4 comprises a pair of rubber seal rolls 4, pressed against each other and the outlet side seal mechanism 5 comprises a pair of rubber seal rolls 51, together with a substantially Jshaped slow cooling tank 52 and a liquid supply pipe 53. The liquid supply pipe 53 supplies a cooling liquid, which serves also to wash the treated cloth, to the slow cooling tank from the outside of the steamer.

A plurality of cloth guide rolls 6 are provided in an up and down zigzag arrangement within the steamer body 1 and serve to transport cloth to be treated continuously through the body 1. The cloth guide rolls 6 have tension control rolls 6' included at appropriate positions in their arrangement. A tank 7 for treating solution is provided in the vicinity of the cloth inlet 2, and a pre-washing tank 8 is provided in the vicinity of the cloth outlet 3.

In addition, the body includes a tank 9 which can hold hot liquid overflowing from the slow cooling tank 52, and a pump 10 to supply hot liquid stored in the hot liquid tank 9 successively or continuously to the pre-washing tank 8. An overflow outlet 11 is provided in the slow cooling tank 53, and a discharge outlet 1 2 for waste liquid is provided in the prewashing tank 8.

The above description sets out the construction of a high pressure steamer provided with a device for supplying liquid to the washing tank according to the present invention. A continuous treatment such as a pretreatment or a dyeing operation effected on a long length of cloth by using such a high pressure steamer may be carried out, for example, as follows: The interior of the steamer body 1 is maintained under conditions of wet heat, for exam ple, at a pressure of about 5.5 kg/cm2 and at a temperature of about 1 60 C, and water is supplied successively from the liquid supply pipe 53 to the slow cooling tank 52 at ambient temperature.The temperature of water in the slow cooling tank 52 is raised due to the high temperature within the steamer body, the temperature of water being relatively low (about 50"C as an example based on the above figures) in the vicinity of the rubber seal rolls and relatively high (about 1 30 C as an example based on the above figures) in the vicinity of the cloth outlet 3. While a cloth to be treated is transported continuously through the steamer body 1, high temperature water overflowing from the slow cooling tank 52 passes through the overflow outlet 11 into the hot liquid tank 9 and is supplied successively to the pre-washing tank 8 by means of the pump 1 0. Water in the pre-washing tank 8 is discharged successively through the discharge outlet 12.

By supplying hot water continuously to the pre-washing tank 8 provided in the steamer body 1, the condensation of steam in the steamer body is effectively prevented so that the interior of the steamer body can be maintained with a wet heat at a uniformly high temperature and pressure. The cloth is steamed effectively, and thus a cloth can be usefully treated thereby.

Moreover, since in the present invention one employs water from the slow cooling tank, which itself is heated by heat exchange with cloth heated by the wet-heat in the steamer body, as the hot water to be supplied to the pre-washing tank, water resources and heat energy can be saved. Thus, the present invention offers an economical apparatus for wet-heat treating a cloth in a continuous manner.

Claims

1. A high pressure steamer for the continuous wet-heat treatment of a cloth, which steamer comprises a steamer body including a pre-washing tank therein and having a cloth inlet and a cloth outlet permitting cloth to be continuously passed through the steamer body, the cloth outlet having an outlet seal mechanism provided with a slow cooling tank, and the steamer including means to supply hot overflow water from the slow cooling tank to the pre-washing tank.

2. A high pressure steamer according to claim 1, wherein the steamer includes a tank into which hot water from the slow cooling tank can overflow and collect.

3. A high pressure steamer according to claim 2, wherein the slow cooling tank includes an overflow pipe which directs an overflow of hot water into the hot water collector tank and the hot water collector tank includes a pipe and pump arranged to pump water from the hot water collector tank to the pre-washing tank.

4. A high pressure steamer according to any one of the preceding claims, which includes inlet and outlet seal mechanisms each comprising a pair of rubber seal rolls.

5. A high pressure steamer according to any one of the preceding claims, wherein the outlet seal includes a J-shaped slow cooling tank.

6. A high pressure steamer according to any one of the preceding claims, which includes a plurality of cloth guide rolls in a zigzag arrangement, together with tension control rolls.

7. A high pressure steamer substantially as hereinbefore described with reference to and as illustrated in the accompanying drawing.

8. A method of continuously treating cloth, which method comprises subjecting the cloth to a wet-heat treatment at a temperature in excess of 1 00 C and at superatmospheric pressure, sufficient to support a saturated va- -i pour as required, the cloth being passed in one step through a pre-washing liquid under said conditions and subsequently through a cooling liquid, and cooling liquid which has been heated by the cloth being used to supply fresh pre-washing liquid.

9. A method according to claim 8, wherein the treatment temperature is from about 150 to about 160"C.

1 0. A method according to claim 8 or claim 9, wherein the treatment is a dyeing treatment.

11. A method according to claim 8 sub stantia lly as hereinbefore described specifically.

1 2. The use of a water supply line to supply hot water overflowing from a slow cooling tank in the outlet of a high pressure steamer to a pre-washing tank within the body of the steamer.