GB2073265A

GB2073265A - A continuous method for dyeing a relatively thick cloth

Info

Publication number: GB2073265A
Application number: GB8110011A
Authority: GB
Original assignee: Sando Iron Works Co Ltd
Current assignee: Sando Iron Works Co Ltd
Priority date: 1980-04-01
Filing date: 1981-03-31
Publication date: 1981-10-14
Also published as: GB2073265B; DE3112408A1; JPS56140158A; MX155721A

Abstract

A continuous method for dyeing a relatively thick cloth, comprising transporting the thick cloth 1 continuously through a high pressure steamer 2 the conditions within which are maintained at a high pressure wet heat in the range of from 100 DEG to 160 DEG C, so the cloth becomes swollen. The cloth 1 is then soaked with a dye solution at a high temperature, by passing e.g. through dye solution tanks 71 and 72. On following the path defined by rolls 11, the cloth is subjected to the wet heat conditions which fix the dye on the cloth. <IMAGE>

Description

SPECIFICATION A continuous method for dyeing a relatively thick cloth The present invention relates to a continuous method for dyeing a relatively thick close, such as one suitable for use as a carpet, a blanket or the like.

Conventional continuous methods for dyeing a long web of a relatively thick cloth for use as a carpet, blanket or the like involve the application of a dye solution to the cloth at ordinary temperatures and pressures and then the fixing of the dye under conditions of wet heat by supplying the cloth to a wet-heat chamber at the ordinary pressure. However, such a method has various problems, particularly when the cloth is relatively broad with a width of more than 4 m, so far as the means for applying the dye solution to the cloth and for wet-heat fixing the dye are concerned.

It is very difficult sufficiently and uniformly to soak with a dye solution a high grade thick cloth having long naps right to the core part of the cloth when the process is conducted at ordinary temperatures, resulting in uneven fixing of the dye.

Furthermore, if the cloth soaked with a dye solution is squeezed in the usual way prior to the wet-heat treatment by means of a pair of squeeze rolls, the squeeze rolls are bent by the squeezing operation, particularly if the thick cloth is broad, causing different nip pressures at the central part and the two sides of the cloth. This results in unavoidable uneven squeezing, with the two sides being squeezed the most. In the case of a relatively thick cloth, there is the further problem that the amount of dye solution squeezed differs at the core part and at the surface part, the surface part being more strongly squeezed, and this also causes uneven dyeing. If the squeezing rate is appropriately controlled for the surface part, the core part will contain excess dye solution, causing wastage of the dye solution.

In the case of the conventional batch-type dyeing method, there are the disadvantages that large quantities of heat energy, dye and processing water are consumed uneconomically.

Furthermore, the tone of dyeing differs between lots, thus frequently producing faulty goods.

In view of the foregoing, it is a prime object of the present invention to offer a superior method for the dyeing of a relatively thick cloth.

Accordingly, this invention provides a continuous method for dyeing a relatively thick cloth, comprising feeding a thick cloth continuously through a high pressure steamer the conditions within which are maintained at high pressure wet-heat with a temperature in the range of from 1000 to 1 600C so that the cloth becomes swollen by those conditions of wet heat, soaking the thus-swollen cloth all over with dye solution at an elevated temperature so that the dye solution penetrates to the core part of the cloth, and then fixing the dye to the cloth under the conditions of the high temperature wet heat within the steamer.

It will be appreciated that by the method of this invention, a relatively thick cloth can be uniformly soaked with a dye solution, and in the following wet-heat treatment in the high pressure steamer the dyeing of the thick cloth can be done effectively and uniformly in a short time.

The cloth may be soaked when swollen with dye solution by being immersed in one, or repeatedly immersed in more than one, dye solution tank within the steamer. Alternatively, the dye solution may be sprayed on to the swollen cloth, on issuing from a plurality of liquid jet nozzles disposed within the steamer.

Preferably, the dye solution applied to the swollen cloth is at a temperature substantially equal to the internal temperature within the steamer. Following soaking of the cloth, excess dye may be aqueezed from the cloth by means for instance of squeeze bars.

This invention extends to a relatively thick cloth whenever dyed by a method of this invention as discussed above.

By way of illustration of this invention, one specific example thereof will now be described in detail, referring to the accompanying drawing which shows a diagrammatic section through an apparatus suitable for performing the method of dyeing a relatively thick cloth.

Referring to Figure 1, a relatively thick cloth 1 having a pile or napped long hairs to be used as a carpet, blanket or the like, is treated on a continuous basis on being passed through a high pressure steamer body 2. The steamer body 2 is provided with a cloth inlet 3 and a cloth outlet 4, and the cloth inlet 3 and the cloth outlet 4 are provided respectively with an inlet seal mechanism 5 and an outlet seal mechanism 6 which allow the transport of the cloth 1 continuously therethrough whilst maintaining the interior conditions of a high temperature wet heat under pressure within the steamer body 2. The present Applicants have made various proposals for suitable seal mechanisms, and an appropriate mechanism for the present case may be selected from those.However, since the seal mechanisms 5 and 6 form no part of the present invention, a detailed discussion of their construction will not be given here.

Dye solution tanks 71 and 72 are provided in the vicinity of the cloth inlet 3 within the steamer body 2, in which dye solution 8 is stored at constant levels so that the solution can be applied to the cloth 1. A cleansing tank 9 is provided in the vicinity of the cloth outlet 4 within the steamer body 2, in which a constant amount of hot water is contained, for cleansing the treated cloth. A plurality of cloth guide rolls 11 define a zig-zag path having runs extending generally up and down and along which the cloth 1 is constrained to pass on being transported through the steamer body 2, so that the cloth is subjected to the wet-heat conditions within the body 2.The temperature of the wet-heat conditions in the steamer body can be selected appropriately to lie within the range of from 1000 to 1600 C, depending upon the nature of the cloth to be treated. Squeeze bars 12 are disposed to squeeze excess dye solution absorbed in the cloth 1, after the cloth leaves the dye solution tanks 7, and 72. A droplet catch plate 13 serves to prevent water droplets falling on the cloth 1, and a slow cooling and liquid seal tank 14 is provided in the outlet seal mechanism 6.

Continuous dyeing of a thick cloth using the above described apparatus proceeds, for instance, as follows.

At first, superheated steam is blown into the steamer body 2 so as to obtain conditions of wetheat in the interior of the steamer body, for instance at a temperature of 1 500 C. A dye solution 8 is introduced in the dye solution tanks 71 and 72, and hot water 9 is introduced in the cleansing tank 9. Thus, the dye solution 8 and hot water 9 are heated up to nearly 1 500 C, in accordance with the temperature in the steamer body 2. The preferable range for the wet-heat treating temperature is from 1300 to 1 C.

Then, a thick cloth 1 to be dyed is supplied to the steamer body 2 through the inlet seal mechanism 5. The thick cloth 1 at once swells due to the wet heat conditions in the steamer body 2.

The thick cloth 1 thus swollen is repeatedly immersed in the hot dye solution 8, first in the dye solution tank 71 and then in tank 72, so that the thick cloth 1 is soaked with the dye solution 8 rapidly and sufficiently right to the core part thereof. Since the cloth 1 is squeezed by the squeeze bars 12 each time after leaving a dye solution tank, the excess dye solution, particularly at the surface part of the cloth 1, is removed to render uniform the dye solution content of the cloth.The resultant cloth 1 is sufficiently wet-heat treated in a short time for fixing the dye in the cloth uniformly on the cloth passing through the steamer body 2 along the path defined by the cloth guide rolls 1 The cloth 1 is then cleansed preliminarily on passing through the hot water 10 in the cleansing tank 9, cooled on passing through the slow cooling tank 14 and taken out of the steamer body 1 through the seal 6.

While the application of hot dye solution to the swollen cloth is done in the described apparatus by immersing the cloth in the dye solution, the method of this invention is not limited to such a step. For instance, the dye solution may be jetted on to the swollen cloth by means of a plurality of liquid jet nozzles provided near the cloth inlet of the steamer body, so as to soak the cloth sufficiently with the dye solution. The use of the squeeze bars 12 can of course be dispensed with in this instance.

Though the object of the present invention is to provide a method of dyeing a thick cloth, the method can naturally also be applied in general to the dyeing of a thin cloth.

As has been explained above, in the method of this invention a cloth in a swollen state is soaked with a dye solution, for instance by immersing the cloth in the dye solution or by jetting the dye solution on to the cloth, when the cloth is in the steamer body. This ensures that the dye solution is absorbed right to the core part of the cloth, uniformly and sufficiently in a short time, even if the cloth is relatively thick. The cloth thus soaked with a dye solution is wet-heat treated with saturated steam at a high temperature and pressure to fix the dye in the cloth. In this way, a relatively thick cloth can be dyed uniformly all over the cloth and right to the core part thereof.

Claims

1. A continuous method for dyeing a relatively thick cloth, comprising feeding a thick cloth continuously through a high pressure steamer the conditions within which are maintained at high pressure wet-heat with a temperature in the range of from 1000 to 1 600C so that the cloth becomes swollen by those conditions of wet heat, soaking the thus-swollen cloth all over with dye solution at an elevated temperature so that the dye solution penetrates to the core part of the cloth, and then fixing the dye to the cloth under the conditions of the high temperature wet heat within the steamer.

2. A continuous method for dyeing a relatively thick cloth according to claim 1, in which the cloth is soaked with the dye solution by being passed through dye solution contained within a tank provided within the steamer.

3. A continuous method for dyeing a relatively thick cloth according to claim 2, in which the cloth is repeatedly soaked with dye solution contained in separate tanks within the steamer.

4. A continuous method for dyeing a relatively thick cloth according to claim 2 or claim 3, in which the cloth is constrained to pass around a guide roll provided within the or each tank.

5. A continuous method for dyeing a relatively thick cloth according to claim 1, in which the cloth is soaked with the dye solution on passing jets of the solution issuing from a plurality of liquid jet nozzles disposed within the steamer.

6. A continuous method for dyeing a relatively thick cloth according to any of the preceding claims, in which the dye solution applied to the swollen cloth is at a temperature substantially equal to the internal temperature within the steamer.

7. A continuous method for dyeing a relatively thick cloth according to any of the preceding claims, wherein the cloth is squeezed following the soaking thereof.

8. A continuous method for dyeing a relatively thick cloth according to claim 1 and substantially as hereinbefore described, with reference to the accompanying drawing.

9. A relatively thick cloth whenever dyed by a method according to any of the preceding claims.