HK1068380A - Equipment and process to finish fabrics in general - Google Patents

Description

Apparatus and method for finishing regular fabrics

The present invention relates generally to apparatus and methods for finishing conventional fabrics, and more particularly to preparing, washing, bleaching, dyeing and finishing fabrics (e.g., flat woven fabrics, tubular fabrics, Raschel warp knit fabrics, Kettentuntl, crepe fabrics and other forms of fabrics) that are commercially available for use in applications such as clothing, home, automotive, medical, and the like.

Today, there are generally various methods and apparatuses for finishing conventional fabrics. There are discontinuous treatments working with so-called exhaustion treatments. The finished fabric is immersed in a bath (water or other organic solvent) where the effective agents (bleach, dye, etc.) are transferred from the bath to the fabric and then to the dye bath solution, almost completely depleted.

Another discontinuous method, known as the Pad Batch (Pad Batch) method, applies a medicament by pressing on a fabric. The article is in winding contact with the medicament on a roller; a certain reaction time (up to 24 hours) must be allowed before the fabric can be finished. In pad steam dyeing, after impregnation with a finish, the fabric is passed through a steam generator to accelerate the above reaction by thermal energy. Both of these methods require washing the fabric in other equipment after the chemical reaction. Thus, both methods require expensive, time consuming preparation and post-processing.

Although the pad-pile tempering method and the pad steam dyeing method require a relatively small amount of water, their use is limited (they cannot be used for cylindrical fabrics); in fact, nowadays, the so-called exhaustion treatment is very important.

Another disadvantage of the above-mentioned conventional systems is that they are very suitable for relatively long fabrics in an economical and technical manner.

The greatest disadvantage of the processes and apparatuses using the so-called exhaustion process is that: the articles must be continuously immersed in a bath containing a bath and then they must be drained again until uniformity is obtained. To obtain uniformity, the fabric is forcibly withdrawn from the bath at one end by a high speed conveyor (up to 500 m/min) and then re-impregnated at the opposite end. This can result in undesirably high fabric mechanical stretch associated with longitudinal stretching and rubbing on the surface (edge peeling), which can negatively impact the quality of the final article. Typically, the fabric cannot be transported by the apparatus in open width form, but in rope form which will form crease marks on the more delicate fabric. The amount of water and electrical energy required to apply the agent and subsequently wash the fabric and during the performance of such processes is very large.

It is therefore an object of the present invention to provide a method and apparatus for finishing conventional textiles which can significantly reduce the electricity, water, time and energy requirements.

Another object of the present invention is to provide a method and an apparatus for finishing conventional fabrics which enable to reduce the costs of preparation and treatment, so that the method and apparatus can be economically applied also to fabrics of shorter length.

Another object of the present invention is to provide a method and a device for finishing conventional fabrics which are capable of minimizing mechanical stretch in the longitudinal direction as well as on the fabric surface, allowing finishing of very delicate and elastic fabrics with different grammage.

Another object of the present invention is to provide a method and an apparatus for finishing conventional fabrics, by which different types of fabrics, such as single layer woven fabrics, knitted fabrics, raschel, Kettenstul, crepe fabrics, non-woven fabrics, etc., can be submitted to a complete wet finishing process (preparation, relaxation, dyeing, washing, rinsing, softening, etc.).

Another object of the present invention is to provide a method and apparatus for finishing conventional fabrics, by which the finishing time and the processing speed of the fabrics can be greatly reduced compared to conventional methods and apparatuses.

Another object of the present invention is to provide a method and a device for finishing conventional fabrics, by means of which a large number of different fabrics to be finished can be quickly exchanged without changing the device.

Another object of the present invention is to provide a method and an apparatus for finishing conventional fabrics, by means of which it is possible to finish a large number of different sizes (between 100 and 350 kg) without changing the manufacturing costs.

The fabric is conveyed through the apparatus in a conventional manner, as is currently the case with existing methods and apparatus, and sewn at the desired length. The fabric is thus gathered in the bath and on the conveyor belt, which first of all results in a smaller-sized arrangement. Thus, aggregation occurs in the following manner: as with the input and transport speeds, the transport speed of the web through the bath and on the conveyor belt is significantly lower. The fabric does not collect on the conveyor belt and no mechanical tension is applied to it.

Another advantage is that: smaller baths can be used for treatment, significantly reducing the water demand and the amount of generated sewage, i.e. by 30-75%.

Another advantage of the present invention is that the fabric being treated is subjected to several presses and/or suctions to ensure that the substrate is placed on the return belt with a defined residual moisture. This method provides a certain dwell time (reaction) which allows to produce speeds lower than 80 m/min, thus making it possible to ensure a treatment without stretching and rubbing.

The treatment time is also short, dyeing lasts about 30 minutes; whereas in the previous treatments 1.5 to 2 hours were required.

The dyebath may be run for about 20 minutes, which may take 3 to 5 hours in the past.

By reducing the dye bath and treatment time, energy consumption can be reduced.

The remainder of the bath after the pressing or suction is returned to the bath of the plant when the dyebath and/or bleaching is carried out; during the washing, the remainder is discharged from the apparatus.

The fabric immersed in the bath is conveyed through the bath itself (for example, by a circulating fluid). Once the feed can be easily set, the gathered web is allowed to run against a sensor, as mentioned in the patent of the invention. The feed rate of the single-layer woven fabric is set according to the force applied here.

In order to avoid the formation of crease marks on the selvedges of the fabric, the wet fabric is transported on a so-called stripping cylinder before the fabric is mechanically removed from the bath following the fabric.

Mechanical grouting can be carried out, for example, by suction or pressing with the aid of rollers. The previously wetted web is then conditioned on what is known as a centralized roll.

The pressed fabric is transported on a return conveyor by means of the guide device. The fabric is gathered on a return conveyor which allows a certain dwell time (e.g. 3 minutes) to occur. For example, when previously impregnated with a dye, they may react with the fibers (assembly) and simultaneously affect the homogeneity before subjecting them to a new impregnation. Also, this method can be applied to other applications such as exhaust.

After the fabric is taken off the conveyor belt, the shade of the colour is measured in a reliable manner to determine the end of the treatment before being re-conveyed to the dyebath, which is inevitably easier to treat with wet fabric than with wet fabric.

As mentioned before, the movement of the gathered web in the bath can be generated, for example, by means of a circulating fluid. Thus, relative movement between the fabric and the bath can facilitate transfer of the dyeing, bleaching or fiber washing pattern. It can also be produced by the back and forth movement of a conveyor belt (in which the fabric in the static bath is accelerated and stopped), so as to convey the fabric in a repeated manner.

Likewise, the movement of the dye bath material can be promoted by bath impingement or by a wet fabric on a vibrating conveyor belt. The size and frequency of the particles of the treatment substance are adjusted.

When finishing fabrics that are very shrinkable, it is advantageous, for example, for elastic articles. The fabric is pre-soaked with the bath before being guided into the bath at the first time, so that the shrunk fabric is guided into the bath. Therefore, a suitable spray (asperator) nozzle must be placed before the inlet opening of the bath; these nozzles are fed by the liquid contained in the bath itself. These nozzles may also be used to deliver the fabric to a chute and/or circular area at the bath inlet to assist in the gathering of the fabric.

The transport of the fabric gathered in the bath can also be carried out by the action of vibrations on a second, lower conveyor belt, which can be provided with vanes or suitable profiles to facilitate the transport of the fabric.

The space of the return belt is optionally closed, thermally conditioned and chemically controlled by introducing a gas such as nitrogen or ozone to avoid undesirable effects.

The conveyor optionally has a vibration generator to assist in bath dyeing by mechanical means.

The apparatus of the invention further comprises a bath filled with a treatment liquid (such as a bleaching agent, a dyeing agent or a washing liquid) which can be adapted to the fabric transport device.

In the circulation direction, at the rear of the bath outlet, there are squeezing rolls to which the fabric being squeezed or sucked is transported from the bath. After the press roll, a guide device is provided, by means of which the wet fabric can be placed on the return belt. The return belt circulates at a slower speed in order to gather the fabric on said return belt.

An auxiliary guide allowing the return of the fabric to the bath is connected at the end of the return belt outlet.

Such equipment may also take the form of a sealed pressurized crankcase for finishing at higher pressures and temperatures.

In the transport direction, an auxiliary guide is provided at the rear of the press roll, in order to place the finished fabric in a tray by means of a folder after the sewing thread has been unraveled.

In the bath, the transport speed of the conveyor belt is as low as the feed and start speed, so that the accumulation occurs there. To avoid jamming the bath, a sensor is provided at its end, the gathered web contacts the sensor, and the feed rate is controlled in accordance with the force exerted by the web.

The bath itself has a base with a large heat exchange area in its lower part to avoid temperature changes.

A discharge opening can be connected to the bath, through which the bath can be supplied to the spray nozzles by means of a pump; these nozzles are able to spray the bath on the fabric introduced into the bath, allowing pre-shrinking of the fabric and transport of the fabric to the inside of the bath in a gathered manner.

A slide and/or circular area is provided at the inlet of the bath. In addition, the bath has a conveyor belt for transporting the collected web, the lower part of which can be easily introduced into the bath. The fabric floats under it and is slowly transported through the bath. For this purpose, the conveyor belt may have a blade. The delivery device may be designed to be reversible periodically to allow for repeated deliveries.

Finally, we propose to provide a pressure variation system on the press roll, whatever the physical characteristics of the fabric, in order to obtain a predetermined pressing value (residual moisture) so as to be able to place it on the return belt.

The invention is described below with reference to the accompanying drawings, in which:

FIG. 1 is a schematic view of an apparatus for finishing a conventional fabric, in particular a single-layer woven fabric;

FIG. 2 is another schematic diagram showing a variation of the apparatus for finishing a conventional fabric in a similar apparatus for small quantities of fabric having a U-shaped chute;

FIG. 3 is another schematic diagram showing a variation of the apparatus used to finish a conventional fabric in a similar apparatus used for inclined baths for cylindrical fabrics;

fig. 4 is another schematic diagram showing an apparatus for finishing a conventional fabric in an apparatus provided in an autoclave tank.

Fig. 1 shows a finishing apparatus consisting of a member E provided with a conveyor belt 3A at the bottom. Below this, a finishing bath 3 is provided, and the fabric T is circulated between them. At the inlet of the apparatus, there is a feeding, concentrating and stripping device 1, which has at least one input drum 2 that can be perforated and has, on the side, at least one device constituted by a nozzle (asperator) 2A, which determines the initial, rapid and uniform penetration of the water with the chemical on the fabric T to be finished. This rapid penetration may cause the fabric T to shrink before coming into contact with the bath itself.

By continuously feeding the fabric T to the finishing bath on the feeding, collecting and trimming device 1 and on the input cylinder 2, the fabric T is gathered there, i.e. the fabric itself can be gathered.

The gathered fabric is slowly conveyed through the bath 3 by means of a suitable conveyor, the inlet of the bath 3 being provided with a chute and/or circular zone 10 and in this zone with a conveyor belt 3A; the fabric floats between the lower part of the conveyor belt and the bottom of the bath 3 and is conveyed by friction or by means of a suitable profile structure. Alternatively, this can be achieved by a design with one or more blades or by a fluid only.

The fabric at the end of the bath is moved against the signalling device 4 for effecting the synchronous movement and controlling the feeding of the fabric T. The feed rate of the fabric gathered in the bath can be adjusted so as not to block the bath.

By means of the guide 11, the edging cylinder 5 and by means of a centraliser 13 able to control the deflection detected by the sensor 12, the fabric T reaches the press roll 6, where the excess liquid is removed mechanically. In the impregnation process (dyeing, bleaching, etc.), the pressed fabric is returned to the bath. In the washing process, the pressed fabric is removed from the apparatus.

By means of the auxiliary guide 11 the fabric reaches the return belt 7A, where it is placed on a vertically inclined guide 9, i.e. with a transport speed lower than that of the single-layer woven fabric. The fabric can stay in wet condition on the extension of the return belt 7A. Thus, the gap and pressure between the squeeze rolls 6 can be adjusted. The moisture of the fabric is adjusted, if possible, at the exit of the rolls and on the return belt 7A.

In the vicinity of the input drum 2, a series of nozzles 2A are provided, which are connected to a pipe system 17 having a pump 18 and a filter 19 connected to the pump 18.

As shown in fig. 1, the dyeing process is performed in three steps (bleaching, drying and washing) in the apparatus. It was found by the following basic measurements that the bath had a length of 2m, a volume of 600 liters and the return strip had a length of 4 m. A towel fabric of 300m with a width of 2,45m is circulated in the apparatus. In three steps, the apparatus was adjusted in the same way; the fabric speed measured at the press roll was 50m/min and the residual moisture was 70%.

The retention time of the fabric in the bath and on the return belt was 3 minutes; 150m of fabric was kept in the bath and 150m on the return belt. The procedure (pretreatment/dyeing/washing) is carried out in a conventional manner by means of temperature and chemicals (hydrogen peroxide, reactive dyes, Remazol dyes (Remazol), detergents, etc.) and the following procedure is carried out: 5 pretreatments, 8 dyeings, and 3 washes. The total water consumption for the 3 cycles is 16.66 liters per kilogram of fabric in total, which is much less than the state of the art for almost 110 liters per kilogram of fabric. The dye bath change time was 6 minutes.

Fig. 2 shows a variant of the apparatus for small quantities of textile material, with a U-shaped chute.

Here, the fabric T is also sewn and brought to the following treatment process by the apparatus. Here, the bath 3 is U-shaped and the fabric T is gathered when it is introduced into the bath. Here, the transport through the bath is carried out in a simple manner by gravity. Without the use of a signaling device, the second layer may deviate from the one that has been created.

The wet fabric T reaches the mud jacking roller 6 through the guiding device 11, the edge peeling roller 5 and the concentration roller 13; from there, onto the extension of the return belt 7A, from which the fabric is re-immersed in the bath 3. A further cloth folder 8 may be provided at the outlet of the apparatus.

Fig. 3 shows a variant of the apparatus, which has a vertically inclined bath 3, in whose chute the liquor circulating in the bath 3 is collected downwards together with the fabric T, which is continuously moving on the press roll 6 via a return belt 7A, as shown.

The present variant is directed to a tubular fabric which, before being extruded, is blown in a known manner by means of air jets 14.

Figure 4 shows the looping of the apparatus in the autoclave tank 15 where the return strip 7A and bath 3 are circular. Here, the transport of the gathered web T through the bath 3 is effected by a dipping drum 16 which has one or more blades or similar devices and can be driven in reverse.

This variant, in which the return belt 7A is constituted almost by the bath 3, enables a very small structure to be formed, thus reducing the cost of the autoclave tank 15. In such an apparatus, polyester fabrics can be dried, for example under the action of pressure and elevated temperature.

A PLC orientation sensor is arranged behind the squeezing roller 6. These sensors are used to determine whether the fabric T can be returned for one or more treatments; it is then placed on a return belt 7A in the device 7 in front of the member E or brought to the end rear, i.e. the folder 8, for removing the treated fabric T from the apparatus E.

All monitoring and overall synchronism of the equipment E is achieved by capacitive sensors, which are able to guide a PLC (programmable logic controller), which in turn can control all the movements of the equipment E during operation.

The apparatus E is directed to the finishing of fabrics T of any kind or pattern, which can be placed on cars, pallets and/or cloth rolls loaded into a feeding, collecting and stripping device 1 with a feed inlet of the apparatus.

Although described and illustrated as a preferred construction, it should be noted that: variations in the schemes are possible and can be made without altering the scope of the invention.

Claims (29)

1. A process for finishing conventional fabrics, characterized by:

-transporting the fabric (T) in a treatment bath (3) in accumulation and in the bath (3) itself; thereafter, the fabric (T) is taken out of the bath so as to be able to squeeze the liquid through the squeezing rollers (6); the fabric can then be conveyed by the return belt (7A) to a new finishing cycle or the finishing can be finished directly; the fabric is removed from the apparatus by a folder (8).

2. A process for finishing conventional textiles as claimed in claim 1, characterised in that: the amount of fabric (T) passing in the bath (3) is controlled by signal means (4) for determining the synchronism and movement of the fabric in the bath (3).

3. A process for finishing conventional textiles according to claim 1 or 2, characterised in that: the fabric (T) passes through the trimming roller (5) both when entering the apparatus via the conveyor (1) and when leaving the bath (3) through the trimming roller (5).

4. A method for finishing regular textiles according to any of claims 1 to 3, characterised in that: when the fabric (T) has passed through the stripping cylinder (5) and the collecting device (13), the excess liquid contained in the fabric (T) is drained off by means of the squeezing roller (6).

5. The method for finishing regular fabrics according to any of claims 1 to 4, characterized in that: the fabric (T) receives the dye bath liquid through the nozzle (2A) before the first contact with the bath itself.

6. The method for finishing regular fabrics according to any of claims 1 to 5, characterized in that: the fabric (T) is introduced into the bath (3) by means of a chute and/or a circular zone (10).

7. The method for finishing regular fabrics according to any of claims 1 to 6, characterized in that: the fabric (T) is transported in a bath (3) in a gathered state and allowed to float below a conveyor belt (3A).

8. The method for finishing regular fabrics according to any of claims 1 to 7, characterized in that: alternatively, the fabric (T) accumulated in the bath (3) can be conveyed by means of a circulating fluid and/or present a reciprocating motion between the fabric and the bath, this motion being achieved by means of a conveyor belt (3A) itself in which the fabric in a static bath can be accelerated and stopped so as to be conveyed repeatedly.

9. The method for finishing regular textiles according to any of claims 1 to 8, characterized in that: alternatively, the bath (3) and/or the conveyor belt (3A) are provided with vibration means.

10. A method for finishing regular textiles according to any of the claims 1 to 9, characterised in that: alternatively, the fabric collected on the return belt (7A) is closed, thermally conditioned and chemically controlled by introducing air in the area of the return belt (7A).

11. The method for finishing regular textiles according to any of claims 1 to 10, characterized in that: alternatively, the fabric (T) is taken out of the bath (3) so that the liquid can be extracted by suction means.

12. Apparatus for finishing regular fabrics, characterized in that: comprises a component (E) provided with a bath (3), a conveyer belt (3A) is arranged in the bath and provided with at least one signal device (4); after the conveyor belt (3A) there are arranged a squeezing roller (6) and a PLC-oriented sensor capable of determining whether to finish or return the treatment or finishing the fabric (T) one or more times; a device (7) consisting of a return belt (7A) is arranged at the front of the apparatus, and a folding machine (8) is arranged at the rear of the apparatus.

13. The apparatus for finishing regular textiles according to claim 12, characterised in that: the component (E) is provided with a stripping roller (5) at the inlet of the device in the feeding device (1) and a stripping roller (5) after the outlet of the bath (3).

14. The apparatus for finishing regular textiles according to claim 12 or 13, characterised in that: a supply device (1) consisting of a tensioning, collecting and trimming drum is provided, and at least one drum (2) is arranged in sequence, which can be perforated and is provided with at least one device consisting of a nozzle (2 a).

15. An apparatus for finishing regular fabrics according to any of claims 12 to 14, characterized in that: the overall monitoring and synchronization is achieved by capacitive PLC-directional sensors, which themselves are able to control the motion of all the devices during their operation.

16. An apparatus for finishing regular textiles according to any of claims 12 to 15, characterised in that: the inlet of the bath (3) is provided with a slideway and/or a circular area (10).

17. An apparatus for finishing regular fabrics according to any of claims 12 to 16, characterized in that: alternatively, the bath (3) and/or the conveyor belt (3A) have a vibration generator.

18. An apparatus for finishing regular textiles according to any of claims 12 to 17, characterised in that: alternatively, the fabric (T) transport device or belt (3A) has one or more blades or suitable profiles to transport the fabric.

19. An apparatus for finishing regular textiles according to any of the claims 12 to 18, characterised in that: the lower part of the bath (3) is provided with a heat exchanger.

20. An apparatus for finishing regular textiles according to any of claims 12 to 19, characterised in that: alternatively, a pressure variation system is provided on the press roll (6) in order to obtain a predetermined pressing value (residual moisture) irrespective of the physical characteristics of the fabric.

21. An apparatus for finishing regular fabrics according to any of claims 12 to 20, characterized in that: alternatively, the transport of the fabric (T) gathered in the bath (3) can also be carried out by means of undulation oscillations on a second lower conveyor belt, which may have one or more blades or suitable profiles to facilitate the transport of the fabric.

22. Structurally modified apparatus for finishing conventional textile fabrics, characterized in that: comprising a member (E) provided with a bath (3), a squeezing roller (6) or a PLC-oriented sensor determining whether the treatment is finished or whether the treatment is to be returned for one or more fabric (T) treatments, where a return belt (7A) is provided at the front of the apparatus and a cloth folder (8) is provided at the end of the apparatus.

23. The apparatus for finishing regular textiles according to claim 22, characterised in that: the inlet of the device comprises a feeding device (1), and a stripping roller (5), a squeezing roller (6) and a guiding device (11) are arranged behind the bath (3).

24. Another structurally modified apparatus for finishing conventional fabrics, characterized in that: comprising a member (E) provided with a vertically inclined bath (3) with a conveyor belt (3A) followed by a squeezing roller (6) and PLC-directional sensors; the PLC-oriented sensor determines whether to end the treatment of the fabric (T) or to return to one or more finishing treatments of the fabric (T); a return belt (7A) is arranged at the front part of the equipment, and a cloth folding machine (8) is arranged at the tail end of the equipment.

25. An apparatus for finishing regular textiles as claimed in claim 24, characterised in that: comprising a feeding device (1) at the inlet of the apparatus and a plurality of squeezing rollers (6) after the bath (3).

26. An apparatus for finishing regular textiles according to claim 24 or 25, characterised in that: an air nozzle (14) for blowing air to the cylindrical fabric is provided in front of the press roll (6).

27. Another structurally modified apparatus for finishing conventional fabrics, characterized in that: comprising a member (E) in the form of an autoclave tank (15) provided with a circular bath (3) and a return belt (7A), and comprising an immersion drum (16) followed by a squeezing roller (6) and PLC-oriented sensors which determine whether the treatment of the fabric (T) is finished or returned for one or more finishing treatments of the fabric (T), wherein a return belt (7A) is provided at the front of the apparatus and a cloth folder (8) is provided at the end of the apparatus.

28. An apparatus for finishing regular textiles as claimed in claim 27, characterised in that: the component (E) is provided with a stripping roller (5) at the inlet of the device in the feeding device (1) and a stripping roller (5) after the outlet of the bath (3).

29. An apparatus for finishing regular textiles according to any of the claims 12 to 28, characterised in that: alternatively, the member (E) is provided with suction means (6) after said belt (3A).