Title of Invention

"A METHOD OF DYEING OF TEXTILE YARN AND FABRIC BY ELECRODEPOSITION AND PRODUCTS THEREOF"

Abstract

A method for dyeing yarn or fabric, by eletrodeposition is disclosed. The method comprising charging yarn or fabric with a charge in a charging device on one end, charging dye with opposite charge from another charging device on another end, interacting intimately the charged yarn or fabric and charged dye so obtained in a space/zone, removing the excess dye form the said zone and yarn or fabric to obtain yarn or fabric with dye deposited on it, heating the said yarn or fabric for ensuring effective fixing of deposited dye to obtain dyed yarn or fabric.

Full Text

The present invention relates to a method for dyeing of textile yam and fabric by electrodeposition and products thereof. Particularly, the invention relates to a method for dyeing of textile yam and fabric. More particularly, the invention relates to a method for dyeing of textile yarn and fabric by electrodepositiuon . Still more particularly, the invention relates to a method for dyeing of textile yam and fabric by electrodeposition and products thereof. Yet more particularly, the invention relates to a method for dyeing of textile yarn and fabric wherein the yam used is polyester yarn. BACKGROUND OF THE INVENTION: During the past few years, developments and improvements in textile wet processing have been principally at introducing processes that enable fast turn around, in-time delivery and shorter run loads. There have been attempt to achieve these goals and these goals have been achieved to some extent by keeping the systems very flexible with very small change over time. The conventional methods of dyeing of a textile yarn or fabric, particularly the polyester yarn or fabric with a dye, particularly with a dispersed dye involves dissolution of dye, particularly dispersed dye in water followed by treatment of yarn or fabric with dissolved dye at a temperature of about 130°C and above in a closed vessel. During this process in the closed vessel, water and or yarn or fabric are/is made to circulate. The dissolved dye penetrates through the surface of the yarn or fabric and gets fixed on to it. The yarn or fabric is allowed to cool. The yarn or fabric is subjected to repeated washings after removal of excess water from it by squeezing. The yarn or fabric is then dried at a temperature above 100 C, preferably at about 120°Ctol30°C. The conventional method of dyeing of a textile yarn or fabric, particularly the polyester yarn or fabric with a dye, particularly with a dispersed dye has many disadvantages. The main disadvantage of this method is that it involves usage of large quantity of water. The water used varies from 40 times to 60 times the weight of the yarn or fabric, which adds to the cost of the process. Further disadvantage of the conventional process is that, the water used is generally deionised and not the ordinary water or hard water, which further adds to cost of the overall process. Still further disadvantage of the conventional process is that, the recovered water generally can not be recycled for further process and can not be discarded in the environment directly. The recovered water has to be subjected for treatment before it is disposed in the environment stream for recovery of useful products and liquid effluent treatment. These requirements further adds to the steps of the dyeing process and to overall cost of the dyeing process. Still another disadvantage of the conventional process is that, the usage of water adds to steps of recovery of excess water and then drying of the yarn or fabric at a high temperature, which adds to cost of the overall dyeing process and results in poor colour fastness of the yarn or fabric. Yet another disadvantage of the conventional process is that, the change of dye colour is tedious process, as it requires to stop the process followed by cleaning of reactor and machines etc before use of another colour of the dye, which not only adds to cost of the process but also makes the overall process an inconvenient process, particularly when change of dye colour is frequently required. Still another disadvantage of the conventional process is that, the treated water is not completely free from the impurities, therefore, such disposed water leads to water pollution problem, when disposed in the environment. To overcome some of the disadvantages of usage of water, as described herein above, some developments have taken place in the area of dyeing of textile yarn or fabric, particularly polyester with a dye, particularly a dispersed dye, with an important aim to minimize the usage of water, if not to totally eliminate the usage of water. One of the known method of dyeing of textile fabric, particularly polyester with a dye, particularly a dispersed dye, which reduces the amount of water required as medium, is the thermosol dyeing. This process has advantage of reducing the amount of water to be used to a greater extent. This process is generally limited to fabric and involves number of dips and nips technique to dye the fabric. Another disadvantage of the known thermosol dyeing process is that, during this process a thin layer of dispersed dye is formed onto the fabric, but with deposition of auxiliary chemicals, such as dispersing agent, thickening agent, etc., which necessitates the step of washing of the dyed fabric followed by drying of the washed fabric. Still another disadvantage of the known thermosol dyeing process is that, the process involves two step drying of the dyed and washed fabric. The first drying is carried out to remove the excess of water at a temperature above 100°C, as in the conventional methods. The second drying is carried out after fixing the dye and such fixing step is carried out after first drying of the dyed fabric. The fixing is carried out at high temperature, preferably above 160°C followed by washing of the dyed fabric after the dye has been fixed properly, which in-turn is followed by second drying. Still further disadvantage of the known thermosol dyeing process is that, if the drying is not uniform while fixing the dye onto the fabric, the dyeing will also be non-uniform. The another known method of dyeing of a fabric, particularly a polyester fabric with a dye, particularly a dispersed dye, which minimizes the use of water and disadvantages associated with the same, is transfer dyeing. During this process of transfer dyeing a paper is first printed with a dye and subsequently the print is transfered from the paper to the fabric. This process involves preparation of colours with auxiliaries and water, followed by application of prepared dye paste onto the paper, which in-turn is dried, and the dried and printed paper is then placed in contact with the fabric with its (paper's) printed side facing towards the fabric. The paper and fabric are pressed against each other and heated at about 160°C and above. The print/dye is then transfered from the printed paper onto the fabric. This process of transfer dyeing has the advantage of minimizing the use of water, but does not totally eliminate the use of water. Further limitation of such known method of transfer dyeing is that, such method are generally limited to the fabric only and can be performed in batch. Still further limitation of such known method of transfer dyeing is that, this process involves an additional steps of selection of suitable paper, printing of paper by applying the prepared dye paste onto the paper and transfering the print/dye from the paper onto the fabric. Therefore, the known methods involving the usage of water, in any amount, as described herein above have many disadvantages as described herein above. To overcome the disadvantages of usage of water, as described herein above, recent developments have taken place in the area of dyeing of textile yarn or fabric, particularly polyester with a dye, particularly a dispersed dye, with an important aim to eliminate the usage of water, as use of water as the medium of dyeing process, substantially increases the cost of dyeing process. The increased cost of overall process is due to water procurement, which is to be preferably deionised and not the hard water or ordinary water. Further, the use of water necessitates water re-cycling and material drying operations, and calls for recovery of useful products from water and liquid effluent treatment before its disposal in the environment stream, as described herein above. The method of dyeing of textile yarn or fabric, particularly polyester with a dye, particularly a dispersed dye, which eliminates the use of water as dyeing medium and known in the art is the mass colouration process. During this process of mass colouration, the dyes are mixed before the filament yarn is made from molten polymer by melt Spinning process. Such known processes have many advantages, such as use of water is totally eliminated and hence the disadvantages associated with the use of water, as described herein above are also eliminated. Further, such known processes are generally one step process for dyeing and spinning together and result in uniform dyeing with better wash fastness property. Such known methods of mass colouration have limitation that, they are generally applicable to the yarn only and not to the fabric. Further limitation of such known methods of mass colouration is that, they are generally suitable for very large scale production of the yarn. For small scale production, such methods are generally uneconomically. Therefore, the small industries, particularly from the developing and under developed countries generally can not afford this process of mass colouration. Still another limitation of such known methods of mass colouration is that, the choice of number of colours is limited, because the dyes required are required to be stable at high temperature. The disadvantage of such known methods of mass colouration is that, the dyes used are generally very expensive and specific, which makes the process uneconomical. Further disadvantage of such known methods of mass colouration is that, for changing colour of the dye, lot of polymer has to be run, which is generally wasted, to clear the effects of the previous dye, otherwise the stains of the previous dye will remain onto the yarn, hence the overall process remains beyond the reach of the small and medium scale industries. Still another known method of dyeing of textile yarn or fabric, particularly polyester with a dye, particularly a dispersed dye, which eliminates the use of water as dyeing medium and known in the art is the super critical dyeing of polyester fabric or yarn. This process eliminates use of water as dyeing medium and the disadvantages associated with the same. During this process of super critical dyeing of the polyester fabric or yarn, the fabric or yarn is dyed at super critical temperature and pressure of corbon dioxide. The main disadvantage of such known method is the requirement of having super critical temperature and pressure of carbon dioxide, which need specilised technology to achieve such required conditions of super critical temperature and pressure of carbon dioxide. Further disadvantage of such known methods of super critical dyeing process of polyester yarn or fabric is that such processes are limited to batch dyeing. Still another disadvantage of such known methods of super critical dyeing process of polyester yarn or fabric is that such processes require sophisticated and advanced autoclaves and autoclaving process. Still further disadvantage of such known methods of super critical dyeing process is that such processes result in poor colour fastness and generaly dye comes out easily. Yet another disadvantage of such known methods of super critical dyeing process is that such processes have possibility of shade variation. Due to such disadvantages and limitations the super critical dyeing process of polyester yarn or fabric has not been commercialised. NEED OF THE INVENTION : Therefore, there is a need of a method for dyeing of yarn and fabric and products thereof, particularly of a method for dyeing of a textile yarn and fabric and products thereof, more particularly of a method for dyeing of a textile yarn and fabric by electrodeposition and products thereof, even more particularly of a method for dyeing of a polyester yarn and fabric by electrodeposition and products thereof, which can eliminate some of the disadvantages of the prior art, if not all, as described herein above and can still has some of the additional advantages over the prior art. OBJECTS OF THE INVENTION : This is the main object of the present invention to make a complete disclosure of a method for dyeing of yarn and fabric and products thereof, particularly of a method for dyeing of a textile yarn and fabric and products thereof, more particularly of a method for dyeing of a textile yarn and fabric by electrodeposition and products thereof, even more particularly of a method for dyeing of a polyester yarn and fabric by electrodeposition and products thereof, which can eliminate some of the disadvantages of the prior art, as described herein above and can still has some of the additional advantages over the prior art. This is another an object of the present invention is to make a complete disclosure of a method for dyeing of a yarn and fabric, and of products thereof, as stated herein above, which totally eliminates the use of water, and the disadvantages and limitations associated thereto, such as increase in the cost of dyeing process due to water procurement, particularly deionised water. It has been observed that, about 40% of the appareal cost of the textile, particularly of polyester production is due to use of water and techniques required to use it and to recycle and dispose it, in a process wherein water is used as dye medium. Still another an object of the present invention is to make a complete disclosure of a method and of products thereof, as stated herein above, which eliminates the problems of re-cycling of used water for recovery of useful products from water and liquid effluent treatment before its disposal in the environment stream and material drying operations, as described herein above. This is further an object of the present invention to make a disclosure of a method and of products thereof, as stated herein above, which eliminates the steps of washing and subsequent drying of the dyed fabric and yarn. Still further an object of the present invention is to make a complete disclosure of a method and of products thereof, as stated herein above, which eliminates the problem of disposal of water (used water) and hence the problem of pollution due to disposed water. This is yet an object of the present invention to make a disclosure of a method and of products thereof, as stated herein above, which is suitable for both, the yarn and the fabric, and is a continous process in nature with a provision of modification as batch process. Yet another an object of the present invention is to make a disclosure of a method and of products thereof, as stated herein above, which does not result in deposition of auxiliary chemicals onto the surface of the dyed fabric and yarn, and result in the uniform dyeing thereof. This is further an object of the present invention to make a disclosure of a method and of products thereof, as stated herein above, which is suitable for small and large scale production and hence is suitable and economical for small and medium scale industries. This is still an object of the present invention to make a disclosure of a method and of products thereof, as stated herein above, wherein choice of colours is possible and wide range of dyes can be used for dyeing the fabric and yarn, particularly polyester fabric and yarn. Still further an object of the present invention is to make a disclosure of a method and of products thereof, as stated herein above, wherein change of colour of dye or change of dye is easy and does not involve running of unwanted length of the fabric and yarn, and hence avoids such financial and material losses. This is yet an object of the present invention to make a disclosure of a method and of products thereof/as stated herein above, wherein the process of dyeing does not call for use of sophisticated and high tech instrumentation. Yet another an object of the present invention is to make a disclosure of a method and of products thereof, as stated herein above, which results in the dyed products having better properties, such as colour and wash fastness, uniform dyeing etc. Other objects will be more apparent from the following description of the present invention. BRIEF DESCRIPTION OF THE INVENTION: Accordingly the present invention provides a method for dyeing of textile yarn or fabric by electrodeposition and product thereof, which comprises charging yam or fabric with a charge in a charging device on one end, charging dye with opposite charge from another charging device on another end, interacting intimately the charged yarn or fabric and charged dye so obtained in a space/zone, removing the excess dye form the said zone and yarn or fabric to obtain yarn or fabric with dye deposited on it, collecting the said removed dye if so desired, heating the said yarn or fabric up to 220 C for ensuring effective fixing of deposited dye to obtain dyed yarn or fabric. In accordance with the preferred embodiment of the present invention the yarn or fabric used may be polyester yarn or polyester fabric. In accordance with other preferred embodiment of the present invention the dye used may be in dispersed form and may be mixed with compressed air. In accordance with another preferred embodiment of the present invention the yarn or fabric may generally be charged with negative charge and the dye used may be charged with the positive charge. The charging of yarn or fabric is effected either by direct contact with the charging electrode or by passing the same through electric field with desired charge. Spraying the charged dye using nozzle(s) carries out the intimate interaction between yarn or fabric and dye. The excess dye from the said space /zone and from the yarn or fabric is collected in preferably separate collectors for the purpose of reuse /recycle. Further, the excess dye is removed from the yarn or fabric (11) by passing the said yarn or fabric through vibrator or air jet. The heating is conducted at a temperature of 120°C to 220°C. According to another preferred embodiment of the present invention two seperate charging devices are used to charge the yarn or fabric, particularly the polyester yarn or fabric and the dye. particularly the dispersed dye, and such charging devices are generally placed at an angle, preferably at right angle to each other. Further, in accordance to another preferred embodiment of the present invention the charging devices comprises of two electrodes generating electric field and one of the electrode acts as negative end and another electrode acts as positive end. In accordance to one of the preferred embodiments of the present invention the yarn or fabric is made to make a contact with one of the electrode of the charging device. Further, in accordance to another preferred embodiment of the present invention, the charged yarn or fabric, particularly the charged polyester yarn or fabric is made to interact with the charged dye, particularly the charged dispersed dye in a common space/origin, preferably in between the two electrodes of the charging device of the dye, particularly the dispersed dye. In accordance to one of the prefered embodiments of this invention the charged dye is sprayed onto the charged yarn or fabric through a nozel or a set of nozels in a common space/origin in between the two electrodes of the charging device of the dye. In accordance to one of the preferred embodiments of this invention the yarn or fabric with deposited dye is made to pass through a vibrator or air jets to remove extra dye and then allowed to pass through a heater or an oven at a temperature of about 120°C or above, preferably upto 2$0°C, which results in the dyed yarn or fabric with fixed dye. Further, in accordance to one of the preferred embodiment of the present invention the extra dye is collected in the dye collector, and one such dye collector is preferably placed below the common space/origin of interaction of charged dye and charged yarn or fabric and another such dye collector is placed below the vibrator or the air jet. Further objects and preferred embodiments of the present invention will be more apparant when read in-conjuction with the accompanied figures, which are not intended to limit the scope of the invention, but are given for better understanding of the invention and the manner in which it is to be performed. DESCRIPTION OF THE FIGURES : Figure-1 shows the plan view of the method and instruments of dyeing of a yarn in accordance to one of the preferred embodiments of the present invention. Figure-2 shows the plan view of the method and instruments of dyeing of a fabric in accordance to one of the preferred embodiments of the present invention. DETAILED DESCRIPTION AND PREFERRED EMBODIMENTS OF THE INVENTION : In accordance to the present invention a method for dyeing of a yarn or fabric, particularly of a textile yarn or fabric, more particularly of a textile yarn or fabric by electrodeposition, even more particularly of a polyester yarn or fabric by electrodeposition and products thereof are disclosed, wherein the method comprises of charging of a yarn or fabric with a charge from the charging device on one end and charging of the dye with a charge from another charging device on another end, and passing the charged yarn or fabric and charged dye through a space/origin, wherein the charged yarn or fabric is made to interact with the charged dye to result in the yarn or fabric with deposited dye, which in-turn is subjected to the heating through a heater or an oven after passing through a vibrator or air jet to remove the extra dye from the yarn or fabric. The dyed yarn or fabric as obtained in accordance to the preferred embodiments of the present invention has better properties, such as better colour and wash fastness, uniform dyeing and uniform shade of colour. Now referring to figure 1, which shows the method and instrumentation of dyeing. of a yarn in accordance to the preferred embodiments of the present invention wherein the method comprises of charging of a, uncharged yarn 1 with the help of charging device 2 on one end 3, and charging of uncharged dye 4 with another charging device 5 on another end 6, and passing the charged yarn 8 and charged dye 9 through a space/zone 10, wherein the charged yarn 8 and charged dye 9 are made to interact to result in the charged yarn 8 with deposited charged dye 9, [labelled as 11 to differentiate from charged yarn 8 or charged dye 9], which [11] in-turn is preferably made to pass through a vibrator or air jet 12 to remove the extra dye 9 from the yarn 8, followed by passing the charged yarn 8 with adequately deposited charged dye 9, [labelled as 13 to differentiate from charged yarn 8 or 11, or charged dye 9], through a heater or an oven 14, wherein the dye 9 penetrates through the yarn 8 and result in the dyed yarn 15 having better properties, such as better depth of dyeing, colour and wash fastness, uniform dyeing and uniform shade of colour. In accordance to one of the preferred embodiments of the present invention, the extra dye 9 from the zone 10 is collected in a dye collector 16, preferably placed adjacent to charging device 5, and extra dye 9ifrom the yarn 11 is collected in another dye collector 17, preferably placed below vibrator 12. However, the present invention is not restricted with the exact location of the dye collectors 16 and 17. In accordance to the preferred embodiments of the present invention, seperate charging devics 2 and 5 are used to charge the yarn 1 or fabric 1 (shown in figure 2). and. the dye 4 respectively, and such charging devices 2 and 5 are preferably placed at angle, preferably at right angle to each other. However, the present invention is not restricted with the respective location of the charging devices 2 and 5. Further, in accordance to another preferred embodiment of the present invention the charging device 2 comprises of two electrodes 18 and 19 generating an electric field 20 and one of the electrode 18/19 acts as negative end and another electrode 19/18 acts as positive end. Similarly, the charging device 5 comprises of two electrodes 21 and 22 generating an electric field 23 and one of the electrode 21/22 acts as negative end and another electrode 22/21 acts as positive end. In accordance to one of the preferred embodiments of the present invention the yarn 1 or fabric 1 (shown in figure 2) is made to make a direct contact with one of the electrode 18 of the charging device 2 at an end 24 of the electrode 18, wherein the yarn 1 or fabric 1 gets charged with the same charge as that of the electrode 18 and the charged yarn 8 is made to pass through end 25 of the electrode 19 to the zone 10. In accordance to another preferred embodiment of the present invention the yarn 1 or fabric 1, as the case may be, can alternately be made to have direct contact with the end 24 of one of the electrode 18 as shown in figure 1 A. Similarly, the dye 4 is made to make direct contact with one of the electrode 21 of the charging device 5 at an end 26 of the electrode 21, wherein the dye 4 gets charged with the same charge as that of the electrode 21 and the charged dye 9 is directed or sprayed onto the charged yarn 8 or fabric 8 (shown in figure 2) in the zone 10. In accordance to one of the preferred embodiments of the present invention, the extra dye 9 from the zone 10 is made to pass through the end 27 of the electrode 22 and collected in the dye collector 16. According to the preferred embodiment of the present invention the dye 4 from the dye hopper 28 is mixed with the compressed air 29 from the air compressor 30 in the air-dye mixer 31 before passing through the charging device 5. This arrangement helps to make spray of charged dye 9 onto the charged yarn 1 or fabric 1 (shown in figure 2). In accordance to the preferred embodiment of the present invention the charged dye 9 is the dye 4 mixed with compressed air 29 in order to spray it onto the charged yarn 1 or fabric 1, as the case may be, and the dye 4 mixed with the compressed air 29 has been labelled as 32 to differentiate it from uncharged dye 4 or charged dye 9. Now referring to figure 2, which shows the method and instrumentation of dyeing of a fabric in accordance to the preferred embodiments of the present invention. The method and instrumentation for dyeing the fabric 1 is almost same as that for the dyeing of yarn 1 as shown in the figure 1 with some variations of configurations of some of the parts of the instrumentation. Same numerals have been used in figure 2 as that of figure 1, to indicate same parts of the instrumentation and same stages of the method of dyeing. However, for the convenience of understanding of the manner in which it is to be performed and to highlight the differences in the instrumentation of the method of dyeing of the fabric 1 is expliained herein below with the help of figure 2. In accordance to the preferred embodiments of the presently disclosed invention, the method comprises of charging of a uncharged fabric 1 with the help of charging device 2 on one end 3, and charging of uncharged dye 4 with another charging device 5 on another end 6, and passing the charged fabric 8 and charged dye 9 through a space/zone 10, wherein the charged fabric 8 and charged dye 9 are made to interact to result in the charged fabric 8 with deposited charged dye 9, [labelled as 11 to differentiate from charged fabric 8 or charged dye 9], which [11] in-turn is preferably made to pass through a vibrator or air jet 12 to remove the extra dye 9 from the fabric 8, followed by passing the charged fabric 8 with adequately deposited charged dye 9, [labelled as 13 to differentiate from charged fabric 8 or 11, or charged dye 9], through a heater or an oven 14, wherein the dye 9 penetrates through the fabric 8 and result in the dyed fabric 15 having better properties, such as better depth of dyeing, colour and wash fastness, uniform dyeing and uniform shade of colour. In accordance to one of the preferred embodiments of the present invention, the extra dye 9 from the zone 10 is collected in a dye collector 16, preferably placed below the zone 10, and extra dye 9 from the fabric 11 is collected in another dye collector 17, preferably placed below the vibrator or air jet 12. However, the present invention is not restricted with the exact location of the dye collectors 16 and 17. In accordance to the preferred embodiments of the present invention, seperate charging devics 2 and 5 are used to charge the fabric 1 and the dye 4 respectively, and such charging devices 2 and 5 are/preferably placed at right angle to each other. However, the present invention is not restricted with the respective location of the charging devices 2 and 5. Further, in accordance to another preferred embodiment of the present invention the charging device 2 comprises of two electrodes 18 and 19 generating an electric field 20 and one of the electrode 18/19 acts as negative end and another electrode 19/18 acts as positive end. Similarly, the charging device 5 comprises of two electrodes 21 and 22 generating an electric field 23 and one of the electrode 21/22 acts as negative end and another electrode 22/21 acts as positive end. In accordance to one of the preferred embodiments of the present invention the fabric 1 is made to make a direct contact with one of the electrode 18 of the charging device 2 at an end 24 of the electrode 18, wherein the fabric 1 gets charged with the same charge as that of the electrode 18 and the charged fabric 8 is made to pass through the zone 10, wherein the charged fabric 8 interacts with the charged dye 9, as described herein below. Similarly, the dye 4 is made to make direct contact with one of the electrode 21 of the charging device 5 at an end 26 of the electrode 21, wherein the dye 4 gets charged with the same charge as that of the electrode 21 and the charged dye 9 is directed or sprayed onto the charged fabric 8 in the zone 10, wherein the charged fabric 8 interacts with the charged dye 9. In accordance to one of the preferred embodiments of the present invention, the charged dye 9 is directed or sprayed onto the charged fabric 8 in the zone 10 from both the sides 6 and 7 [the numeral 7 has not been used to indicate any part of the method or the instrumentation of figure 1] and under such arrangements the dye 4/32 is charged with same charge with the help of two charging devices 5 and 5a preferably placed onto the opposite sides 6 and 7 of the charged fabric 8. The charging device 5a preferably has the same construction as that of the charging device 5, that is has two electrodes 21 a and 22a forming electric field 23a. The dye 4/32 makes a direct contact with one of electrode 21 a at an end 26a, wherein it (4/32) gets charged with the same charge as that of the electrode 21 a and the charged dye 9a is directed or sprayed onto the charged fabric 8 in the zone 10 through electrode 22a from the side 7. The suffix "a" has been added to each numeral 21, 22, 23, 26 and 27 to indicate same parts of the charging device 5a as that of the charging device 5. In accordance to the another preferred embodiment of the present invention, the charged dye 9/9a is sprayed onto the charged fabric 8 through a nozel or a set of nozels 33/33a without touching the electrode 22/22a from both the sides 6 and 7 of the charged fabric 8. In accordance to one of the preferred embodiments of the present invention, the extra dye 9/9a from the zone 10 is collected in the dye collector 16, and collected dye 9/9a losses its charge and is recycled in the process, which result in minimizing wastage of dye and hence reducing the cost of the dyeing process. According to the preferred embodiment of the present invention the dye 4 from the dye hopper 28 is mixed with the compressed air 29 from the air compressor 30 in the air-dye mixer 31 before passing through the charging device 5 and 5a, and has been labelled as 32 to differentiate it from uncharged dye 4 or charged dye 9/9a. This arrangement (not shown in the figure) is also same as that of the figure 1, with line 32 dividing into two lines (not shown in the figure) to reach both the charging devices 5 and 5a and helps to make spray of charged dye 9/9a onto the charged fabric 1 through a nozel or a set of nozels 33 and 33a. In accordance to one of the preferred embodiments of the present invention the charge on the yarn 1 or fabric 1, particularly on the polyester yarn 1 or fabric 1 is opposite to that of the dye 4, particularly of the dispersed dye 4, that is, if the charged yarn 8 or fabric 8, particularly the polyester yarn 8 or fabric 8 is of negative charge, then the charged dye 9, particularly the charged dispersed dye 9 is of positive charge. Further, in accordance to another preferred embodiment of the present invention, the charged yarn 8 or fabric 8, particularly the charged polyester yarn 8 or fabric 8 is made to interact with the charged dye 9, particularly the charged dispersed dye 9 in a common space/origin/zone 10, which is preferably in between the two electrodes 21 and 22 of the charging device 5 of the dye 4/32 (figure 1) or in between the electrode 22 of the charging device 5 and electrode 22a of the charging device 5a of the dye 4/32 (figure 2). In accordance to the another prefered embodiment of this invention the charged dye 9/9a is sprayed onto the charged yarn 8 or fabric 8 through a nozel or a set of nozels 33/33a in a common space/origin/zone 10 in between the two electrodes 21 and 22 of the charging device 5 of the dye 4/32 (figure 1) or in between the electrode 22 of the charging device 5 and electrode 22a of the charging device 5a of the dye 4/32 (figure 2). In accordance to one of the preferred embodiments of this invention the charged yarn 8or charged fabric 8 with deposited charged dye 9/9a, labelled as 11, is made to pass through a vibrator or air jets 12 to remove extra dye 9/9a and then allowed to pass through a heater or an oven 14 at a temperature of about 120°C or above, preferably upto 2200 C, which results in the dyed yarn 15 or fabric 15 with fixed dye. It is understood from the foregoing decsription that, the presently disclosed method and instrumentation for dyeing of a yarn and fabric has various advantages over the prior art and has overcome many of the disadvantages and limitations of the known methods and instrumentations of the prior art, as described herein above. The present invention has been explained with the help of the accompanying figures 1 and 2, which represent two alternative methods and instrumentations of the presently disclosed invention. The instrumentation of figure 2M7 can also be used for dyeing of a yarn. The present description has been directed for polyester yarn and fabric, however, the presently disclosed method and instrumentation can be used for dyeing of other classes of textile yarns and fabrics. Further, the presently disclosed method and instrumentation for dye deposition and fixation could be carried-out on-line in a continuous manner and in batch manner to give uniformly dyed yarn or fabric. It is obvious to those, working in this field, that many alternatives are possible to the preferred embodiments of the presently disclosed invention, which has been explained with the help of the accompanied figures, which are not intended to limit the scope of the invention, but are given for better understanding of the invention and the manner in which it is to performed, without deviating from the scope of the present invention. WE CLAIM: 1. A method for dyeing of textile yarn or fabric by electrodeposition and product thereof, which comprises charging yarn or fabric (1), with a charge in a charging device (2) on one end (3), charging dye (4) with opposite charge from another charging device (5) on another end (6), interacting intimately the charged yarn or fabric and charged dye so obtained in a space/zone (10), removing the excess dye form the said zone (10) and yarn or fabric (11) to obtain yarn or fabric with dye adequately deposited on it (13), collecting the said removed dye if so desired, heating the said yarn or fabric 220 C for ensuring effective fixing of deposited dye to obtain dyed yarn or fabric. 2. A method as claimed in claim 1 wherein the yam or fabric used is polyester yarn or polyester fabric. 3. A method as claimed in claim 1 wherein the dye used is mixed with compressed air. 4. A method as claimed in claim 1 wherein the yam or fabric is generally charged with negative charge and the dye used is charged with the positive charge. 5. A method as claimed in claim 1 wherein the interaction between yarn or fabric and dye is carried out by spraying the charged dye using nozzle(s). 6. A method as claimed in claim 1 wherein, the excess dye is removed from the yarn or fabric (11) by passing the said yarn or fabric through vibrator or air jet. 7. A method as claimed in claim 1 wherein heating is conducted at a temperature of l20°C to 220°C. 8. A method for dyeing textile yam or fabric substantially herein described with reference to the drawings accompanying this specification.

Documents:

2954-del-1998-abstract.pdf

2954-del-1998-claims.pdf

2954-del-1998-correspondence-others.pdf

2954-del-1998-correspondence-po.pdf

2954-del-1998-description (complete).pdf

2954-del-1998-drawings.pdf

2954-del-1998-form-1.pdf

2954-del-1998-form-13.pdf

2954-del-1998-form-19.pdf

2954-del-1998-form-2.pdf

2954-del-1998-form-26.pdf

2954-del-1998-form-3.pdf

2954-del-1998-form-6.pdf

2954-del-1998-gpa.pdf