WO2009088382A1

WO2009088382A1 - Application of the finishing material on the warp

Info

Publication number: WO2009088382A1
Application number: PCT/TR2008/000062
Authority: WO
Inventors: Erdinc Taskoparan
Original assignee: Gap Guneydogu Tekstil Sanayi Ve Ticaret Anonim Sirketi
Priority date: 2008-01-11
Filing date: 2008-06-03
Publication date: 2009-07-16
Also published as: TR200800218A2

Abstract

The invention relates to a denim fabric production method comprising the process steps of thread production, rope winding, rope dyeing, rope opening in the denim fabric production, wherein during the size application process, a thread-coating composition, comprising preferably a polyurethane- or polyethylene-containing solution or the similar, is applied on the warp threads in such a way that the thread appearance and properties will not be hindered.

Description

APPLICATION OF THE FINISHING MATERIAL ON THE WARP Technical Field

The invention relates to a process, which will provide innovative features for the fabric in the denim fabric production, by eliminating the traditional sizing application.

The invention relates in particular to a process, wherein a solution containing a thread-coating material such as polyurethane or the like is applied on the warp threads during the sizing process of the denim fabric production.

State of the Art Today, there are two different process flows in the denim fabric production, namely "the rope dyeing" and "the beam dyeing". Of these, according to the method referred to as "the rope dyeing", following process steps are sequentially performed to obtain the denim fabric:

Thread Production: The ginned cotton fiber, which is generally supplied in the form of bales, is opened and cleaned in the blowroom machine, after which the fibers are brought into parallel form as a band and strip, respectively in the carding machine and draw frame. If the thread is to be produced according to the open- end spinning technique, the slivers are fed into the open-end thread machine to be converted to the open-end thread, and said open-end thread is the classical thread for the denim fabric. However, during the recent years, the ring thread has also found a rather intensive use. In case of conversion into the thread by means of ring spinning, the slivers will need to be thinned once more in the flyer, to be brought into cord form. The desired ring thread is obtained by feeding the cords to the ring machine. During the recent years, the threads with special effects have also been preferred as a design element for the denim fabrics. Coreyarn threads, corespun threads and polyester threads are the demanded threads that provide the effects.

Rope winding: The threads that arrive in the form of bobbins from the spinning mills or the external thread producers are brought into rope form according to the desired number of yarns. Rope dyeing: The ropes are passed through the dye troughs according to the desired darkness and effect.

Rope opening: Each rope is wound onto a beam such that the threads will be parallel. Size application: The raw weaving beams are duplicated according to the desired warp spacing, and these are subjected to the sizing solution in the sizing machine that will increase the resistance of the threads against the tensions they will experience during the weaving, and thus the weaving beam is prepared.

Weaving: The warp threads having only the outer surface thereof dyed by means of indigo dyeing are woven in the weaving machine in a way to form a fabric with the weft threads, with the application of designs. In this way, the raw denim fabric is obtained.

Fabric Fixing: Raw denim fabric is passed in stretched state through the hot cubicles in the ram to be fixed according to the desired width. Finishing/Compactor: The denim fabric whose width has been fixed is first subjected in a continuous manner to the burning process to remove its surface piles. Then it is subjected to the twisting process according to the twisting ratio envisaged, in order to enable the fabric to remain stable after the washing. Finally, the fabric is exposed to the pressing process by a felt that forms high pressure around a drum heated with steam.

Confection and Stone Washing: The denim fabric that has been subjected to the aforesaid processes is now a ready-to-use fabric. After this fabric is converted into the trousers- or jacket-type of dress by means of the confection process, it is washed in the stone washing machine with the abrasive stones and chemicals to abrade the indigo dyes on the outer surfaces of the warp threads and thus to obtain the blue-white appearance, which is the classical outlook for the denim.

Many improvements have been made in the whole denim fabric production or the sub-processes thereof; hence many patents have been granted and also many patent applications have been filed. Of these, some are mentioned below: In the patent document no. TR96/00795 titled "Sizing apparatus for the weaving warp", the invention relates to sizing the weaving warp by means of a biological sizing component that is readily dissolved, based on the principle of applying the vertical weaving warp path-sizing. The main components: Warp drum, size application section, drying section and warp wood. The size application section comprises the following: a) At least one lower warp path changing roller, which serves as the tangential warp management roller relative to the lower size application roller, b) two size application equipment (K) located on both ends of the weaving warp path, each comprising two rollers, which rollers have the duty of equally distributing the sizing component to the weaving warp and have their layer thickness adjustable via the Gap Adjustment (S). The fixed thickness extent of the sizing layer in the weaving warp is maintained by means of the difference in the travel speeds between the roller and the weaving warp.

According to the invention in the patent document no. TR2002/01870 titled "Method for preparing the warp threads for weaving", in the production of the fabrics with or without design, the warp threads are wound onto the adjustable narrow beams with a width of about 30-60 cm, with an intensity that is equal to or higher than that in the weaving beam, according to the serial warp method. Once an amount of beams sufficient to form a lot has been wound, the beams are attached to a bar with no intervals therebetween, in order to obtain a one-piece beam. Depending on the requirement, said one-piece beam is delivered to size application, weaving, drawing-in room and transfer. During the size application, the threads unwound from separate beams included in the one-piece beam, which is placed on the stand, are passed through the separator plates, the tension adjusters assigned to each beam and the combiner card, and are delivered to the sizing trough and to the drying apparatus. The threads leaving the drying apparatus are passed through the separator card and the distributor card, and are conveyed to the sizing beam. The band is adhered on the ends of both threads, in order to connect together the new and the old threads in the sizing machine.

Application of a finishing material, such as polyurethane, on the warp is not able to be performed according to the methods currently known. In the woven fabric production, the technology for preparing the warp threads for the weaving process is conventionally carried out as follows depending on the fabric production and the type of the warp threads used: In the production of the fabrics with simple knits having no design, the warp threads are unwound from a certain number of bobbins placed into the creel of the serial warp machine, and are wound onto the warp beam in parallel. Then a lot is formed from said beams, and the threads are subjected to the size application and/or transfer to the weaving beam processes. The number of warp threads in the whole lot is equal to the number of warp threads in the fabric to be woven. The intensity of the threads in the warp beam is less than the intensity in the weaving beam, by an extent proportional to the number of beams in the lot. During the size application, the beams are placed on the stands in the rear part of the sizing machine, and the threads in these beams are brought together. Then these threads and the ends of the previous thread bundle remaining from the previous lot located to the rear of the sizing trough are subjected together to sizing in the sizing trough by way of knotting at three or more locations, dried in the drying zone, and are passed through the cross bars and the distributor cards to be wound onto the sizing beam. The obtained sizing beams are conveyed to the drawing-in room or to the weaving looms. For the production of the fabrics with design, the warp threads are unwound from the bobbins in the low-capacity creels in the conical warp machines, and are wound onto a conical drum in the form of bands forming the color report. The number of threads wound onto the drum is kept equal to the number of threads to be wound onto the weaving beam. The length of one band is equal to the warp length in the beam. After the necessary number of bands are wound onto the drum, all the bands are unwound from the drum and are transferred onto the beam. When the transfer process is complete, this beam is conveyed to the size application, drawing-in and/or weaving loom. The technology for preparing the warp threads for the weaving according to the present method has the following drawbacks:

1. There are rather excessive time losses during the charging of the beams in a lot onto the sizing and transfer machines (aligning the beams on the stand, applying the separator threads, removing and re-attaching the separator cross bars, manually passing the threads through the teeth of the distributor card),

2. The threads unwound from separately placed warp beams have varying tensions. 3. The braking system is not in the same configuration for each warp bean,

4. It is necessary for the sizing and warp transfer machines to have a consiα length, because a high number (2 to 12) of warp beams and the correspondinl number of cross bars are used in said machines. 5. The efficiency is low in the conical warp process.

6. There is a significantly high thread wastage during the charging of the new beam lots.

According to said patent document, in the production of the fabrics with or without design, the warp threads are wound onto the adjustable narrow beams with a width of about 30-60 cm, with an intensity that is equal to or higher than that in the weaving beam, according to the serial warp method. Once an amount of beams sufficient to form a lot has been wound, the beams are attached to a bar with no intervals therebetween, in order to obtain a one-piece beam. Depending on the requirement, said one-piece beam is delivered to size application, weaving, drawing-in room and transfer. During the size application, the threads unwound from separate beams included in the one-piece beam, which is placed on the stand, are passed through the separator plates, the tension adjusters assigned to each beam and the combiner card, and are delivered to the sizing trough and to the drying apparatus. The threads leaving the drying apparatus are passed through the separator card and the distributor card, and are conveyed to the sizing beam. The band is adhered on the ends of both threads, in order to connect together the new and the old threads in the sizing machine, and said ends are wound for several runs onto a cylindrical bar. Then, they are flexibly tied to each other at several locations on the edges and in the middle of this bar. The characteristic chemicals such as polyurethane are applied on the fabric during the finishing process to provide brightness and a better appearance for the denim fabric. During said application on the fabric, both the warp and the weft threads contact polyurethane. This in turn leads to the disappearance of the contrast between the warp and weft thread, and impairs the natural outlook of the denim. Size application is one of the known manufacturing processes for the denim fabric. In this process, it is aimed to prevent the fuzzing out and the break likely to occur due to the impacts the warp thread will be exposed to during the weaving. In order to prevent these from occurring, the thread is coated with a material called size component, which comprises starch, oil and various chemicals. Size component covers the surface of the thread in a film-like manner to provide the same with strength, thus it also reduces the subsequent breaks occurring during the difficult process of weaving, and it improves the yield and quality. However, the size material that improves the yield and quality of weaving considerably affects the appearance and the structure of the fabric. Consequently, the fabric is subjected to many processes after the weaving, in order to remove the size material in an effort to return the fabric to the previous appearance and the structure. Unfortunately, these processes both increase the costs associated with the fabric production and fail to enable the fabric to revert to its original appearance. According to the new method, the use of the size material is avoided to eliminate the negative impact of this material on the denim production process.

Moreover, since the threads are very dense in the warp beams in the normal sizing machines, said machines comprise two troughs designed so as to perform an effective size application owing to the sizing of one half of the threads in one trough and the other half of the threads in a second trough.

As a result, the presence of the need for the application of the finishing materials on the warp and the inadequacy of the existing solutions have made it necessary to provide an improvement in the relevant art.

Object of the Invention

In order to eliminate the disadvantages of the state of the art, the objects of the invention are as follows:

• The fabric is enabled to attain a brighter and a more distinguished appearance, as well as increasing its fastness to washing, touch and some specific performances.

• This will be the beginning of a new era in denim production. In addition, the size material, which is mandatory in the standard denim production process, is not used. Thus, the negative effect left by this material on the fabric is also prevented. • Some modifications have been provided in the sizing machine, in order to perform the new method with success in the sizing machine.

• In this method, the warp path is reduced to only one trough in the sizing machine and all the warps are enabled to pass through a single trough. • Improvement is observed in the crocking values of the fabrics produced according to the new method, as compared to the fabrics produced according to the standard method.

• The weft thread remains clean in the application of the warp, and the fabric attains better breathing capacity. • Since no size material is used, there is no need for a size component removal process both for denim finish and the trousers.

• Owing to the warp application, a much better appearance is obtained than the appearance obtained by the application on the fabric.

• According to the new method, the wet and dry croching values are better, with the other side of the fabric remaining cleaner as compared to the classical method.

• In the case of application on the warp, the problems with the warp and weft strength, which are encountered in the application on the fabric, are encountered to a lesser extent. • The coating flotte is provided between the warp and the delivery cylinder, to form an artificial chamber/reservoir between the warp and the cylinder.

• The appearance and the performance features are improved by means of addition of the coloring pigments, glimmer-providing metal powders or the additional performance enhancer particulates such as Tiθ₂ or nano silver ions to improve the appearance of the threads, to the polyurethane which is the coating material used.

• Only the surfaces of the warp threads are coated with the material enhancing the thread appearance and features. Detailed Description of the Invention

The invention relates to a process wherein a thread-coating material, such as a polyurethane- or polyethylene-containing solution or the similar, is applied on the warp threads during the size application process of the denim fabric production. The invention also relates generally to the performance of the process steps of the thread production, rope winding, rope dyeing, rope opening, sizing, weaving, fabric fixing, compaction, confection and stone washing under the method referred to as "rope dyeing", wherein the said step of sizing is carried out without the use of a size material. The most important difference of this patent subject, for which the application is being made, from the standard denim fabric production process occurs in the size application process. In said process, the rope winding, indigo and rope opening processes, which are the steps of the denim fabric production up to the size application process, have no difference than the standard denim fabric production process. The weaving and denim finishing processes that take place after the size application step are not either different from the standard process. Below are the process steps for said denim fabric production:

Thread Production: The ginned cotton fiber, which is generally supplied in the form of bales, is opened and cleaned in the blowroom machine, after which the fibers are brought into parallel form as a band and strip, respectively in the carding machine and draw frame. If the thread is to be produced according to the open- end spinning technique, the slivers are fed into the open-end thread machine to be converted to the open-end thread, and said open-end thread is the classical thread for the denim fabric. However, during the recent years, the ring thread has also found a rather intensive use. In case of conversion into the thread by means of ring spinning, the slivers will need to be thinned once more in the flyer, to be brought into cord form. The desired ring thread is obtained by feeding the cords to the ring machine. During the recent years, the threads with special effects have also been preferred as a design element for the denim fabrics. Coreyam threads, corespun threads and polyester threads are the demanded threads that provide the effects. Rope winding: The threads that arrive in the form of bobbins from the spinning mills or the external thread producers are brought into rope form according to the desired number of yarns.

Rope dyeing: The ropes are passed through the dye troughs according to the desired darkness and effect.

Rope opening: Each rope is wound onto a beam such that the threads will be parallel.

Size application: The raw weaving beams are duplicated according to the desired warp spacing, and during the size application process in the sizing machine, a thread-coating material, such as a polyurethane- or polyethylene-containing solution or similar, is applied on the warp threads without subjecting these to a size material, so that the resistance of the threads is increased against the tensions they will experience while they are joined in the weaving step, and thus the weaving beam is prepared.

Weaving: The warp threads having only the outer surface thereof dyed by means of indigo dyeing are woven in the weaving machine in a way to form a fabric with the weft threads, with the application of designs. In this way, the raw denim fabric is obtained. Fabric Fixing: Raw denim fabric is passed in stretched state through the hot cubicles in the ram to be fixed according to the desired width.

Finishing/Compactor: The denim fabric whose width has been fixed is first subjected in a continuous manner to the burning process to remove its surface piles. Then it is subjected to the twisting process according to the twisting ratio envisaged, in order to enable the fabric to remain stable after the washing. Finally, the fabric is exposed to the pressing process by a felt that forms high pressure around a drum heated with steam.

According to the new method, the characteristic chemicals such as polyurethane or polyethylene may be applied on the warp thread during the sizing process, consequently, the weft thread does not contact the chemical. This enables the contrast between the warp and the weft threads to be preserved, and the natural appearance of the denim is maintained.

Also, the system involving the circulation of the flotte (solution) from the lower trough to the upper trough is modified by providing the flotte between the warp and the cylinder by means of a jet nozzle, thus an artificial chamber/reservoir is formed between the warp and the cylinder. Owing to this artificial reservoir, the efficiency of application is increased by the supply of flotte from the top on the warp.

The solution used according to the new method is prepared in cold water, and comprises 250 g/lt polyurethane (the commercial product named PERAPRET PU or similar products), 25 g/lt catalyst (the commercial product named PERAPRET TX or similar products), 10 g/lt wetting agent (the commercial product named LEONIL or similar products), 0,5 g/lt anti-foam agent (the commercial product named DEFOMER or the similar products).

The protective scope of this application is determined in the section of the claims, and the scope may by no means be limited to the description above provided only for exemplary purposes. It is obvious that a person skilled in the art may provide the innovation put forward by the invention also by using the similar embodiments and/or may apply this embodiment to the other fields used in the relevant art for similar purposes. Consequently, such embodiments would obviously lack the criterion of innovative step.

Claims

1. The invention is a denim fabric production method comprising the process steps of thread production, rope winding, rope dyeing, rope opening in the denim fabric production characterized in that during the size application process, a thread-coating composition, comprising preferably a polyurethane- or polyethylene-containing solution or the similar, is applied on the warp threads in such a way that the thread appearance and properties will not be hindered, without any size material being applied.

2. A method according to Claim 1 characterized in that the warp coating process is preferably carried out in a single trough.

3. A method according to Claim 1 characterized in that in the warp coating process, the coating composition is supplied between the warp and the delivery cylinder, and thus an artificial chamber/reservoir is formed between the warp and the cylinder.

4. A method according to Claim 1 characterized in that the coloring pigments, glimmer-providing metal powders or the additional performance enhancer particulates such as TΪO₂ or nano silver ions are added to said coating composition to improve the appearance of the threads.

5. The invention is a coating composition for use in the size application step of a denim fabric production method comprising the process steps of thread production, rope winding, rope dyeing, rope opening in the denim fabric production characterized in that it contains the certain proportions of polyurethane, catalyst, wetting agent and anti-foam agent prepared in water.

6. A composition according to Claim 5 characterized in that it is prepared in cold water.

7. A composition according to Claim 5 characterized in that it contains 240 to 260 g/lt polyurethane.

8. A composition according to Claim 5 characterized in that it contains 23 to 27 g/lt catalyst.

9. A composition according to Claim 5 characterized in that it contains 8 to 12 g/lt wetting agent.

10. A composition according to Claim 5 characterized in that it contains 0,3 to 0,7 g/lt anti-foam agent.

11. The invention is a denim fabric comprising the process steps of thread production, rope winding, rope dyeing, rope opening in the denim fabric production characterized in that it is a fabric, which is coated, during the size application process, with the coating composition according to Claims 5 to 10, without any size material being applied.

12. A fabric according to Claim 11 characterized in that it is a fabric that will comprise the warp to be obtained by way of coating process of only the warp thread surfaces with the materials that will enhance the appearance and the properties of the thread, and that it is a fabric that will be woven from said warp.