FIELD OF THE INVENTION

¾ The present invention in general relates to a fabric manufacturing process and more particularly, to a process of manufacturing of a denim-like corduroy fabric that behaves like denim and a fabric therefrom.

BACKGROUND OF THE INVENTION

¾ In today s textile industries, all fabric producers supply the corduroy fabric that is being dyed by either a batch dyeing process or a continuous process wherein reactive dyes for cotton fabric and disperse dyes for polyester fabric are used for dyeing.

Presently, a tone-to-tone colour variation in the corduroy fabric is obtained ¾ by using a pigment dyeing or coating the fabric. In the pigment dyeing process, a layer of dye is formed on either side of the fabric. Further, by using coating process, a colour variation may be achieved on both sides of the fabric. In this process the fabric is coated by a coating agent. The coating agent may be applied in a foam form or a paste form. However, it ttl is found that the dye only forms a superficial coating layer over the yarns of the fabric and does not penetrate into the fabric. The superficially attached dye gets removed easily and result into defective dyed fabric. The dyes/pigments are fixed on fabric surface by mechanical/chemical bonding. It is purely an adhesion and no chemical reaction involved. However, the pigment dyeing process and the coating process have limitations. These processes do not give a denim-like look to the garment.

¾ Another option is colouring the yarns of the corduroy fabric at yarn stage.

However, the yarn dyeing process itself is a lengthy process that involves various steps like winding on soft package, preparation, dyeing of yarn, drying and rewinding of coloured yarns. These processes increase the cost of the corduroy fabric. The coloured yarn thus produced generates

¾ coloured fluff during the corduroy fabric manufacturing processes which may not be allowed to dispose as the disposal of the coloured fluff is more harmful to the environment.

Therefore, there is need of a process of manufacturing denim-like corduroy fabric that involves the less number of processing steps. Also, ¾ there is need of a process that eliminates a formation of coloured fluff generation during various processes like weaving, cutting, brushing and the like.

S U MMARY OF T H E INVE NTION

ttl Accordingly, in first aspect, the present invention provides a process for manufacturing of a denim-like corduroy fabric. The process comprises the steps of: providing a pre-dyed corduroy fabric having a plurality of pile yarns at least on face side, foam dyeing the pre-dyed corduroy fabric with a dye having fading characteristics, on at least face side by allowing the foam to collapse at least on the face side of the pre-dyed corduroy fabric to deliver dye on the surface of the pre-dyed corduroy fabric using a foam dyeing technology, and washing and drying the corduroy fabric having

¾ denim-like attribution.

In an embodiment, the step providing a pre-dyed corduroy fabric includes a step of a providing a greige corduroy fabric having a plurality of pile yarns at least on face side and pre-dyeing the corduroy fabric for providing a base colour to the corduroy fabric.

¾ In second aspect the present invention provides a denim-like corduroy fabric comprising plurality weft yarns, weft yarns and a plurality of pile yarns at least on a face side of the fabric, wherein the fabric is pre-dyed to provide base colour and the face side is foam dyed to deliver fading dye on the surface of the corduroy fabric to have a denim-like attribution to the corduroy fabric.

According to an embodiment of the invention, the pile yarns of the corduroy fabric are either of warp yarns or weft yarns.

In third another aspect, the present invention provides a garment comprising a denim-like corduroy fabric according to the first aspect of the ttl present invention or denim-like corduroy fabric manufactured by a process according to the second aspect of the present invention. B rief des c ription of the drawings

FIG . 1A is a representative fabric cross-section view of a woven fabric before cutting, in accordance with the present invention;

FIG . 1 B is a representative fabric cross-section after cutting a float weft ¾ from FIG . 1 A;

FIG . 2 is a side view of a corduroy cutting machine;

FIG . 3 is a cross sectional view of a weft-cut dyed yarn of a corduroy fabric, in accordance with the present invention; and

FIG .4 is a process for manufacturing of a denim-like corduroy fabric ¾ according to the one of the embodiment of the present invention.

DE TAIL E D DE S C RIPTION OF TH E INVE NTION

The invention described herein is explained using specific exemplary details for better understanding. However, the invention disclosed can be ¾ worked on by a person skilled in the art without the use of these specific details.

References in the specification to "one embodiment" or "an embodiment" means that a particular feature, structure, characteristic, or function described in connection with the embodiment is included in at least one ttl embodiment of the invention. The appearances of the phrase Ίη one embodiment _, in various places in the specification are not necessarily all referring to the same embodiment. References in the specification to ^' preferred embodiment _, means that a particular feature, structure, characteristic, or function described in detail thereby omitting known constructions and functions for clear description of the present invention.

¾ The present invention in general provides a denim-like corduroy fabric and a process for manufacturing the same. The process for manufacturing a denim-like corduroy fabric involves steps of providing a pre-dyed corduroy fabric having a plurality of pile yarns at least on face side which is, foam dyed with a dye having fading characteristics on at least face side and

¾ washing and drying the corduroy fabric having denim-like attribution. The step of foam dyed is carried out by a foam dyeing machine wherein foam of dye allowed to collapse at least on the face side of the pre-dyed corduroy fabric to deliver dye on the surface of the pre-dyed corduroy fabric.

¾ According to the present invention, the step providing a pre-dyed corduroy fabric includes a step of a providing a corduroy fabric having a plurality of pile yarns at least on face side and dyeing the corduroy fabric for providing a base colour to the corduroy fabric.

According to the present invention, warp and weft count of yarn ranges of ttl the denim-like corduroy fabric is from 8 Ne to 60 Ne, more particularly, 10 Ne to 40 Ne. The weight of the denim-like corduroy fabric is between 4 Oz/square yard to 1 6 Oz/square yard more particularly, 6 Oz/square yard to 1 1 Oz/square yard. According to the present invention, the pile yarns of the corduroy fabric are either of warp yarn or weft yarn.

The present invention is illustrated with reference to the accompanying drawings, throughout which reference numbers indicate corresponding

¾ parts in the various FIG . 1 -4.

In one aspect, the present invention provides a woven corduroy fabric and garments made thereof that behaves like a denim by fading colour in each wash. Referring now to FIG S . 1 A, 1 B and 2, a woven corduroy fabric 100A and 100B includes weft yarns 102 and warp yarns 104. The weft yarns

¾ 102 and warp yarns 104 are arranged in a predetermined manner such that the weft yarn 102 passes over and under at least 4 and maximum of 1 6 warp yarns 104 to form a loop portion. However, it is understood that the weft yarn 102 may include any number of warp yarns to form the loop portion in other alternative embodiments of the present invention.

¾ The weft yarn 102 include a hard yarn 106, an elastomeric yarn 108 and a combination thereof or the weft yarn is hard yarn only. In one embodiment the weft yarn 102 arranged in a predetermined manner such that the at least one hard yarn 106 is arranged with the at least one elastomeric yarn 108. The warp yarn 104 includes a hard un-dyed yarn. The weft yarn 102 ttl passes along a back side 105 of the warp yarn 104 to form an under portion 1 12. The weft yarn 102 passes along a face side 107 of the warp yarn 104 to form an over-portion 1 1 0. In another embodiment, the weft yarn 102 may include either the hard yarns 106 or the elastomeric yarns 108. It is understood here that the hard yarn 106 and the elastomeric yarn 108 may be of different type in other alternative embodiments of the present invention.

In another aspect, the present invention provides a process for

¾ manufacturing a denim-like corduroy fabric. S pecifically, the process is described in conjunction with FIG . 1 -2 and 4. The process described herein below also includes a conventional method for manufacturing an un-dyed or greige corduroy fabric by way of example and does not limit the invention to the said conventional method for a step 410 of providing a

¾ greige corduroy fabric for the present invention.

In the conventional method, initial step includes warping yarns to form a beam of warp yarns. For beam making, the yarns from the cone or cheese packages are wound in a parallel position. The beam is made from a set of number of warp yarns of same count or differential count. However, it is

¾ understood here that the count of the yarns depends on the type and structure of the fabric. In the next step of the conventional method, the process involves sizing of the warp yarns. The sizing is carried out using a sizing machine wherein a protective adhesive coating is applied upon the warp yarns. F or sizing, the warp yarns are laid in a parallel orientation. The ttl warp yarn is withdrawn from the warp beam and is placed on a back side of the sizing machine. F urther, the warp yarn is passed through a size box and immersed in a sizing solution. After removing the surplus solution from the warp yarns, the warp yarns are dried and arranged on a loom beam. The sizing with a mixture strengthens the warp yarns to withstand a rigorous weaving.

In the next step of the conventional method, the process involves making a woven corduroy fabric from the sized warp and the weft yarn.

¾ In the next step of the conventional method, the process involves forming a weft pile fabric by cutting a weft float 1 14 of the weft yarn 102 of the woven fabric to formed a greige corduroy fabric having weft pile yarns. The raised yarns after cutting the weft float are called as or known as yarn piles. The weft float 1 14 of the weft yarn 102 is cut using a corduroy

¾ cutting machine 200 as shown in FIG . 2. The corduroy cutting machine 200 has a shaft that includes a plurality of circular knives and a plurality of needles thereon. The knives are mounted adjacent to one another. E ach needle has a longitudinal slot :L ~ The knives A dip into respective longitudinal slots L formed in the plurality of needles E . The plurality of

¾ needles is pushed into the floating wefts 1 14 to cut open in the direction opposite to that of the fabric web and lower and upper contact strips which are respectively disposed below and above the points of the needles. A gap between the periphery of the circular knives and a cutting edge of the machine 200 is adjusted such that the floating wefts 1 14 of the web ttl travelling through are cut without damaging the ground web or backing.

In a further step of the conventional method, the process involves brushing the weft pile fabric 302 causing alignment of the weft pile fabric 302 in a vertical direction to a fabric plain thereby forming a corduroy fabric. The weft pile fabric 302 is raised onto the surface of the fabric. The weft pile fabric 302 is known as a cord and a fabric obtained by the brushing process is known as the corduroy fabric having weft piles. Alternatively, fabric may have warp yarns as piles wherein fabric having warp float is

¾ formed and cut to form yarn piles in warp direction. In other words, the corduroy fabric is a corduroy fabric having warp pile yarns.

In the next step of the conventional method, the process involves singeing the corduroy fabric at a predefined temperature. The brushed corduroy fabric has hairy fibers that protrude from cut yarn and base fabric as well.

¾ This operation keeps the pile intact but removes protruding fibers. The singeing operation is carried out to remove these fibers. In an embodiment the corduroy fabric passes at a predetermined speed through a flame having a temperature that ranges from about 900 degree centigrade to about 1 100 degree centigrade for removing the protruding

¾ fibers and hairiness from the fabric.

In the further step of the conventional method, the process involves de- sizing of the corduroy fabric wherein the size from the warp yarn is removed. F urther, the corduroy fabric is sent for a scouring/bleaching to remove impurities, natural yellowness of cotton, cotton-seed skin and ttl improve whiteness thereof to obtain a greige corduroy fabric having a plurality of pile yarns.

According to the present invention, referring FIG . 4 shows the process for manufacturing a denim-like corduroy fabric involving a step 410 of providing a greige corduroy fabric and a step 420 of pre-dyeing of the greige corduroy fabric wherein the dyeing of the corduroy fabric with a base dye is carried out using a continuous dyeing machine. According to the present invention, the pre-dyeing is achieved by using the base dye

¾ selected from the group consisting of an indigo dye and a sulphur dye and a reactive dye to give a base colour to the corduroy fabric.

In the next step and according to the present invention, the process for manufacturing a denim-like corduroy fabric involves a step 430 of re- dyeing the pre-dyed corduroy fabric on a face side 107 and/or a back side

¾ 105 thereof using a foam dyeing technology. In this process, the dye liquid is converted into a foam and applied on the fabric face. The foam collapses at least on the face of the corduroy fabric and delivers dye on the surface of the corduroy fabric. It is understood here, that different intensities and/or shades of dyes may be applied on either the face side or

¾ both face and back sides of the fabric as per the requirement. This process facilitates the dye delivery on the yarn surface such as ring dyeing that facilitates washing down like denim in the garment form. The foam dyeing includes a dye selected from the group consisting of an indigo dye and sulphur dye.

ttl In a further step, the process involves a step 440 of washing and drying of the corduroy fabric. The dyed fabric is first washed with known wetting agent for wetting the fabric, known soaping agents and chelating agents, at around 60 degree centigrade and then washed with hot water at around 55 degree centigrade. The washed corduroy fabric is further washed with hot water followed by a cold wash in a continuous washing machine. The fabric obtained is the denim-like corduroy fabric having fading characteristics substantially similar to the denim fabric.

¾ With reference to the present invention, the dyeing process can be proceeds in such a way that only top layer 304, the warp yarn 104 and weft pile fabric 302 of the corduroy fabric get dyed with higher concentration of same dye or with different dye as shown in FIG . 3. The base layer 306 of fabric can be dyed with a lighter shade of the same dye

¾ or with different dye.

In summary, the present invention discloses a process for producing a denim-like corduroy fabric with un-dyed warp and weft yarn 102. The steps involve warping, sizing, weaving of the corduroy woven denim fabric that is dyed in continuous dyeing machine with indigo, sulphur or reactive dyes to

¾ obtain the base coloured corduroy fabric. F urther, the dyed fabric is again dyed with indigo or sulphur or combinations thereof on the face side 304 or the back side 306. The process gives the denim-like corduroy fabric having tone-to-tone colour or the colour differ from the face side 304 and the back side 306. The denim-like corduroy fabric may be rinsed washed, ttl desized washed, enzyme washed, stone washed, sandblast, hand scrapped, sprayed with colour removing chemicals or treated in other ways that allows varying amounts of the un-dyed cores 308 of the yarns to become visible. The garments stitched or manufactured from the denim-like corduroy fabric of the present invention exhibit fading properties substantially similar to the denim fabric. In other words, the garment made from the denim-like corduroy fabric of the present invention gets every time fresh appearance

¾ like how denim garments after every wash.

The present invention has created a new category of corduroy fabric that behaves like denim and allows all creative washes same as denim. Moreover, same or different dyes with same or different color shades, intensities can be used in pre-dyeing and foam dyeing process for

¾ manufacturing the denim-like corduroy fabric which gives a different appearance to the denim-like corduroy fabric and garments made thereof. The dyeing with foam helps to reduce the use of steam, water and energy. The foregoing description of specific embodiments of the present invention has been presented for purposes of illustration and description. They are

¾ not intended to be exhaustive or to limit the present invention to the precise forms disclosed, and obviously many modifications and variations are possible in light of the above teaching.

The embodiments were chosen and described in order to best explain the principles of the present invention and its practical application, to thereby ttl enable others, skilled in the art to best utilize the present invention and various embodiments with various modifications as are suited to the particular use contemplated. The various modifications such as the step 410 of providing a pre-dyed corduroy fabric includes buying a greige corduroy fabric and pre-dyeing at one place or buying pre-dyed corduroy fabric and only foam dyeing the said corduroy fabric at another place to achieve fabric of the present invention may be made without departing from the invention in its broader aspects, some of which changes and ¾ modifications being matters of routine engineering or design, and others being apparent after study.

It is understood that various omission and substitutions of equivalents are contemplated as circumstance may suggest or render expedient, but such are intended to cover the application or implementation without departing ¾ from the scope of the present invention. Accordingly, the aim of the appended claims is to cover all such changes and modifications as fall within the scope of the invention.