[0001] This application claims priority from US Provisional application number

62756853 filed November 7, 2018. This provisional application is incorporated by reference in its entirety.

Background

[ 0002 ] Cotton based denim material was invented in approximately in the 1500’s in Genoa, Italy. Since then, denim has been used in the manufacturing of denim garments and home furnishings. The usage and appearance of denim has swayed with the needs and wants of the cultures within which it is produced. For decades, denim fashion has sought conflicting goals involving denim textiles with very deep or dark colors that are to be removed later wholly or partially through costly treatments on dry fabric or garment washing. Attaining the dark colors involved making the dyes adhere to the yarns increasingly well, but with the need to later wash or abrade the same materials into lighter colored results using unsustainable water, chemical, energy, and manual labor resources that have taxed the environment and manufacturers unimaginably. [ 0003] Denim involves many weaving pattern practices, but the most common is where the warp yams are dyed, and the weft yams are their original color or white. The iconic trait traditional denim possesses is where white warp yarns are immersed in indigo and/or sulfur dye, where the dye does not fully penetrate the yarn diameter. It is named“ring dye” because it is intended to leave a ring of indigo over a white core. This in itself does not necessarily create the iconic look, but rather the exposure to chemicals and/or physical wear (authentic or manufactured) where the indigo or sulfur dye is removed to create a wide array of looks, often resulting in the common “salt and pepper” look of contrasting highs and lows.

[ 0004 ] Figure 1 shows examples of garments that are dyed dark and then

processed through dry and wet processing methods to selectively remove color.

[ 0005] This manual wear or chemical treatment tends to result in areas where the whole or part of the previously dyed yarns reveals the white core, or a reduced darkness of original shade. With repeated exposure to wear, washing, and drying, garments often take on a unique weathered appearance. A pocket repeatedly filled with the same wallet may, after time, experience increased abrasion where the wallet pressed on the yams as the wearer repeatedly sat, rode, ran, stood, or lay for extended periods of time. This increased exposure to wear often leads to the increased rate of dye removal in that particular area, resulting in a garment with a wallet shaped pattern, lighter in color, or actually white (or near white). Commonly sought after attributes are garments with some areas of the garments look quite dark in color, but with other areas of the garment lightened in a naturally worn pattern as described. These wear patterns or chemical exposure are often replicated on garments designed for retail consumption. These characteristics of denim tend to personalize a garment to the wearer.

[ 0006] The fashion industry has struggled for decades with the demand for garments to begin the product cycle with deep rich color and still easily provide various color loss appearances. As denim involves a spun (open ended or ring spun), which is basically white yam being dyed in order to achieve the deep rich colors desired by the industry, denim mills have been developing techniques to better apply increasing amounts of indigo and other dyes to the warp yarns. This development occurs at the early stages of the dying process. Spun cotton warp begin as simple uncleaned of natural impurities and undyed cotton fibers that are natural and essentially near white. The spun warp yams are processed through a series of stages on what is commonly known as a“dye range.” The warp yarns are either treated singularly on a slasher type dye range or more commonly on what is referred to as a rope range. On a rope range, individual warp yarns are bunched into groups of approximately 350-400 parallel yams without twist in a grouping. Cotton is a naturally grown fiber that is exposed to contaminants and debris, both organic and inorganic. Along with the naturally contaminants from the growing fields are plant- based cell wall waxes that coat the cotton fibers. These contaminants and waxes act as barriers resisting chemical and dye penetration of the spun yam. Standard practice is thus to thoroughly clean the yarns in the early steps on the dye range.

[0007] This pre-dye process is generically referred to as scouring. The warp yarns are exposed to what is commonly known as a scour bath in order to remove the natural contaminants and waxes. Prior art teaches that in order to achieve the desirable dark colors the scour must penetrate the yarn as completely as possible in order remove the waxes and impurities, which then allows the dye to accumulate in deep bands on the yam. This deep yam penetration of the dyes is conventionally thought to be the only way to achieve the dark dyed colors desired. However, in doing so, other problems arise.

[ 0008 ] Penetration of the scouring agents is assisted through the use of high temperatures (traditionally -70-80° C.) and the heavy use of chemicals. These chemicals are traditionally comprised of a wetting agent with a concentration of approximately 8 g/L, caustic (50% NaOH) at a concentration of approximately 180 g/L. The high temperature caustic bath with the wetting agent swells the yarns for better removal of previously mentioned contaminants, debris, and waxes. After exposure to the scour bath, the yarns are processed through a series of heated or steam filled rollers to provide a high temperature dwell time for the chemicals to be allowed to penetrate and clean before rinsing. Traditional rinsing involves the yams passing through three traditional clean water rinsing vats, and then ultimately processed through a set of nip rollers to squeeze excess water and chemicals before proceeding to dyeing.

[0009] The dying process is performed in essentially two stages that are repeated as necessary, traditionally 5-12 times. In the first stage, the warp yams of denim are exposed by dipping or immersing into an indigo dye bath that coats the denim. This dye bath involves a high temperature (~60°C) chemical combination largely devoid of oxygen that when paired with caustic NaOH and sodium hydrosulfite (Na2S204) results in normally insoluble indigo becoming soluble (called the“leuco state” in the dye bath vat). The high heat and presence of caustic (50% NaOH) is for the purposes of further indigo penetration into the warp yarns. Between stages of dyeing, the yarns again pass through a set of nip rollers to squeeze the excess dye solution from the yams. For the second dyeing stage, the denim is“skyed.”“Skying” can be understood to mean that after immersing the yams in the indigo bath they are suspended between a series of rollers and exposed to oxygen for a period of time. This exposure to oxygen“fixes” the dye to the yams as it returns to its insoluble state while coated on the cotton yarns. The amount of time spent in the dye bath, relative to the time spent“skying” is often referred to as an immersion: oxidation ratio. Prior standard practices have dictated for decades that optimal oxidation time occurs at an immersion: oxidation ratio of 1 :6. These steps are repeated, as a single exposure to indigo dyeing and subsequent oxidation time is only capable of coating the yams minimally, resulting in a slightly deeper color change. The repetition of the

[ 0010 ] dyeing process increases the amount of indigo retained on the yams and consequently darkens the yarns to the desired tones. Each dye addition is commonly referred to as a dip.

[ 0011 ] After the yarns are exposed to the appropriate number of dye vats and subsequent skying stages, the yarns are mn through vats of water, traditionally 2-4 vats for rinsing and processed through a set of nip rollers to remove excess moisture and then are passed over heated dmms for drying. The dyed warp yarns are coated (also known as“sized” or“slashed”) in protective materials either on the latter stages of the dye range normally on another separate range before being passed over heated dmms for drying and re-beaming the individual warp yarns. The sizing may consist of rice starch, cornstarch, or potato starch, or a synthetic compound such as polyvinyl alcohol (PVA). The starch provides tensile strength to the warp yams, a smooth surface, and lubrication to reduce the number of yams broken in the weaving process. Alternately, the size can be applied on a slasher specifically designed for such.

[0012 ] The dyed yams are then woven with the weft yarns which are traditionally undyed. After weaving, many products undergo various stages of post-weaving finishing. Summary of the Invention

[ 0013] Through experimentation and analysis, the inventors discovered a series of inventive denim mill ring dye process changes capable of resolving the fashion industry’s conflicting goals, with the unheard of benefit of reducing both costs and environmental impact at both the denim mill, and garment finishing and washing (laundry) facilities.

Brief Description of the Drawings

[0014] Figure 1 shows different kinds of washed denim jeans;

[0015] Figure 2 shows a Schematic of Non-uniform Dye Penetration

[ 0016] Figure 3 shows a Schematic of Uniform Dye Penetration

[0017 ] Figure 4 shows Denim Abrasion with Potassium Permanganate Treatment; and

[0018] Figure 5 shows a typical dyeing treatment process.

Detailed Description

[0019] The Inventors realized that associating dye color with depth of yarn penetration of dye in the prior art will not produce the benefits of this invention.

Prior art and standard denim ring dye mill practices created opportunities to drive indigo deep into the yarn. However contrary to this well accepted practice, the inventors realized the importance of cleaning only the outside perimeter of the yam, while leaving the core of the yarn filled with the original waxes and impurities. This novel inventive concept resists dye penetration into the white yam core and consequently preserves a larger portion of the white core than common practices or prior art. Inventors realized that attempts at preserving the white core through various methods had the added benefit of also retaining the circular shape of the core to achieve a more uniform fastness or "fixing" of the dye to the yarns. Retaining the circular shape achieves greater uniformity of fastness, but does not necessarily, as a standalone step, increase fastness without other operations also discussed herein.

[ 0020 ] Additional benefits of a circular shaped core will be expanded later in this specification.

[0021 ] One embodiment of the disclosed invention begins at the yam stage. Yarns are twisted, with the twist counted as a number of twists per inch. Traditionally lower twist multiple ratios are favored as the lower twist multiple results in lower yarn density, which in turn allows for greater scour and dye penetration into the depths of the yam cores. A common twist multiple factor for traditionally dyed warp yarns may be from 3.0 - 4.5 and weft yarns 4.0-5.0. As disclosed in this invention, the inventors identified the novel value in retaining the white core through the

inimization of scour and/or dye penetration, and as a result, this invention uniquely favors relatively high twist multiple ratios. The increased twist multiple factor increases the density of the yarn, making the waxes and impurities resistant to removal, particularly from the inner core. One embodiment of this invention is the implementation of the favorable, high twist multiple ratios such as warp yam twist multiple ratios from about 4.4 to about 4.6 or higher and 4.9 - 5.1 for weft yams.

The inventors discovered that these higher twist ratios reduce penetration at both the scour and dye immersion steps.

[ 0022 ] The inventors challenged the prior art and traditional concepts of scouring and subsequently realized surprising benefits. Scouring with prior art practices involves several methods intent on thorough removal of waxes, debris, and

impurities. The inventive approach here is for thorough, yet minimally invasive scouring but only for the outer yarn surface. This unique concept results, for the first time, in an outer yam perimeter that is scoured while retaining a waxy, dye resistant core. Thus indigo dye can be removed from the outer yam perimeter more easily during dye process abrasion and the initial stone, enzyme, and bleach garment washing process.

[0023] This alone can generate significant savings in overhead costs, water, energy, and chemicals in the laundry process for denim jeans.

[ 0024 ] Another embodiment is a change in the scouring temperature. The scouring in one embodiment, reduces temperatures from the conventional 70° C. to about 30° C or even room temperature,

[ 0025] Yet another embodiment of the invention is the reduced concentration of the chemicals used within the scouring stage. Concentration of wetting agents in the scour vat is reduced from the -8 g/L traditionally used to about 2 g/L. Caustic, which

is key to the scouring process for yarn penetration, is also reduced from a traditional vat concentration of -180 g/L to about 60 g/L.

[ 0026] Yet another embodiment is to reduce immersion time in the scour vat. The immersion time could be reduced by: 1). skipping rollers, 2). changing the path of rollers, 3). lowering the diameter of the rollers, 4). removing rollers, 5).reducing the collective volume of chemicals relative to the size of the vat or 6). Any other practice that results in reduced immersion time in the scour vats. One embodiment is where skipping rollers or changing the path of rollers involve entirely skipping scour boxes. Each of these practices are contrary to the well accepted practices in the conventional ring or rope or indigo dye mill practices. However, any one of these inventive concepts change the scouring depth and degree and can result in much improved denim garment washing processes. Employment of some or all of these contrary practices have a dramatic effect on the denim garment washing process in terms of sustainability, cost savings, water usage, energy, chemical usage, and washing time.

[ 0027 ] Different adjustments and variations to temperature, concentrations, chemicals, immersion time, etc. can be used depending on the mill, but the goal is still the same, to scour the outer yam perimeter while retaining a waxy dye-resistant core.

[ 0028 ] An embodiment of this invention defines a reduction in dwell time and reduction in temperatures between the scouring vat and the rinsing stages. As disclosed above, traditionally yarns are exposed to the scour vat and then passed through a series of heated rollers.

[ 0029] In an embodiment, a goal is only to scour the outer perimeter of the yarn while retaining the dye resistant waxy core with higher density, this embodiment involves the significant reduction in both dwell time and roller temperatures. The roller temperature may be reduced from ~ 70° C to about 30° C. or even room temperature. A further embodiment is to reduce dwell time by the skipping of some of the rollers, reducing the diameter of the rollers, eliminating rollers, or shortening the spans between the rollers involved with dwell time between scour and scour rinsing stages. A reduction in dwell time occurred when the number of rollers used for dwell time at this stage was reduced from 6 to 3 which resulted in the dwell time to be reduced from about 60 seconds to about 30 seconds. In this embodiment,

Dwell time on rollers refers to the rollers that the yarns pass through from one tank to the next.

[ 0030 ] The rinsing of the scour chemicals traditionally involves 3 rinsing vats. Inventors have experienced increased dye penetration with repeated exposure to water, thus another embodiment of the disclosed invention is reducing the rinsing stages from 3 to 2 or even 1. Reduction in exposure to water and temperature is a repeating factor and should be covered for each stage.

[ 0031 ] Throughout the scouring and dyeing process, the warp yarns are exposed to a series of chemicals. Whether scouring, rinsing, dyeing, or sizing, the chemicals are applied through exposure in vats which, to varying degrees, soak the yarns. To remove the excess chemicals, the production involves several nip or squeeze rollers. The yarns are pinched between the nip rollers which creates a wringing and squeezing action, reducing the volume of water, chemicals, or dye on the yarns. Nip rollers squeeze out the scour and dye before the yam enters a new immersion stage, or dwell and oxidation stages. With scour it reduces dwell time, with dye vats it reduces dwell time and conceivably increases oxidation. Traditionally the goal was to maximize scour and maximize the dye penetration. Consequently, the nip pressures were kept relatively low, -4 bar, allowing a relatively high volumes of chemical or dye continue to dwell on the yarns. However, this invention again goes against the prior art such that another embodiment of this invention is to increase nip pressures to a range of about 5.0 to as high as 7.0 bar throughout the scour, dye, and rinse stages. This increased nip pressure serves the novel effect of reduced

penetration of scour, of water, or dye through the reduction of volume of each chemical or dye between stages which is an embodiment of this invention.

[ 0032 ] Yams, having been spun, scoured, rinsed and squeezed through nip rollers then proceed to the first indigo or sulfur dye vat. Traditional practices continue the theme of maximum dye penetration. Traditional dye vats are operated at a

temperature of about 60° C. with a pH range of 11.0 - 12.5 Sodium Hydrosulfite (used to reduce or make soluble the indigo) levels are maintained between about 1.0 - 2.0 g/L with millivolts kept in a range from 680 - 710. Each of these variables creates a dye vat more conducive for indigo or other dyes to penetrate to the core of the warp yarn - the exact opposite of our invention that intends to limit such penetration so as to realize marked benefits in the denim garment dry process and/or washing procedures.

[ 0033] Applying the novel approach of lessening yarn penetration with dye, as well as other chemicals, several additional embodiments of the disclosed invention are associated with the dye vat stage. One such embodiment is continued reduction in temperature from the traditional about 60° C. to about 30° C. or even room temperature. An additional embodiment is to further reduce temperature below room temperature. Yet another embodiment is a narrower pH range which is ideally between 12.0 - 12,5, but is tolerant of a range between 11.0 - 12.5. Different

[ 0034 ] Sodium hydrosulfite levels are an embodiment of the disclosed invention as they are maintained in a low, narrower band of 0.8 - 1.2 g/L, An additional embodiment is the levels of caustic, which are raised from -5.0 g/L to -5.5 g/L to offset the reduced levels of hydrosulfite where millivolts are slightly higher than traditional, from a range of -680 to -710 to a range of -680 to about 775.

[0035] Yet another embodiment is the nature of the indigo itself. Traditionally mills dye their goods with pre-reduced 20%-40% leuco indigo paste. Inventors have found surprising results using dye cakes or powdered indigo forms that are not pre- reduced. Inventors have found that this novel chemistry state in the dye box is the most conducive for the complete saturation of the outer perimeter of the yarn, while leaving the waxy impure core much more uniformly shaped and white or natural coloring, which is critical in this invention. Traditional dyeing techniques with traditional scouring techniques result in indigo on weight of warp yarns being -2.0% whereas the application of disclosed inventive techniques shared within this document result in indigo on weight of warp yarns being 0.75% - 1.25%, a marked and most unusual reduction while still maintaining the same dark appearance on the warp yam exterior. This weight reduction is yet another embodiment of the invention.

[ 0036] Sodium hydrosulfite (or sodium dithionite) is currently a common chemical used as an indigo reducing agent. The levels of sodium hydrosulfite are tailored so as to reduce the openness of the yarns while still successful in putting the indigo into“leuco” reduction state. Yet another embodiment is the implementation of monosaccharides and/or disaccharides as a reduction agent at volumes and concentrations that achieve parallel results with the disclosed vat chemistry with or without intent of replicating disclosed invention. The development of pectin as a reducing agent, when used in a manner that achieves the same goal as that disclosed in the invention regarding reduction agents is another embodiment. Yet another embodiment would invol ve a combination of the disclosed reducing agents, or even the use of yet discovered, realized, or implemented reducing agents when used in such a way that similar results are achieved. Purposeful avoidance of yarn dye penetration beyond the outer perimeter is an embodiment. The outer perimeter could be defined as within 10 35% depth penetration in an embodiment.

[ 0037 ] In another embodiment, dyes penetrate the core but experience little or no fastness, but percentages should be entirely avoided for scouring. [ 0038 ] In embodiments, the reference to lack of penetration into the core means that the dye carries out less penetration into the core. There may still be some dye penetration into the core, but a small enough amount that the dye does not color the core discussion of There is room for a reasonably convincing debate on whether or not the scour penetrates the core, but is simply less effective due to other variables involved.

[ 0039] After the warp yams proceed through the immersion stage in the dye box, involving a series of rollers within the vat, the yams are again passed through nip rollers with increased pressures as disclosed within this specification.

[ 0040 ] After the nip rollers, the yarns then are exposed to the“skying” process. This is the stage where the yams, coated with the soluble“leuco” indigo state dwell in open air, exposing the indigo to oxidize and“fixing” it to the yarn as it returns to its insoluble state. Traditionally and after years of experience operating rope dye ranges, it was believed that the ideal ratio of immersion to oxidation is 1 : 6.

Inventors have conducted trials where fastness, or fixing of the indigo to the yams, appears to greatly increase with continued oxidation time or skying beyond this conventional ratio. One embodiment of the disclosed invention is increasing the oxidation time to shift the ratio higher than 1 :6. Ratios of 1 :6 to 1 : 15 could produce even better results. Incremental increases in oxidation time greater than 1:6 qualifies as an embodiment of this invention. [ 0041 ] This cycle of exposing the yams to dye and then oxidizing them may he repeated numerous times - even 8 or more times. After the dyeing vat boxes, the yarns again pass through a nip roller before being passed through a final rinsing stage. The prior art again calls for repeatedly exposing the yams to water with most dye ranges having 2-4 rinse vats with all available traditionally used. One

embodiment of this invention is to further lessen the yams exposure to water, and eliminate all but one of the rinse cycles since the lower indigo applied on weight of the warp yams is fully oxidized, pass through the nip rollers before proceeding into the sizing operation. Conventional methods and processing techniques would involve using all rinse tanks available. As such, the reduction of the number of rinse tanks from 4 to 3, 4 to 2, and 3 to 2 or 1 would also qualify as an embodiment of the disclosed invention.

[ 0042 ] Sizing (or slashing) is traditionally a natural starch that is added to the yams via an additional vat immersion that can be on the indigo dye range, but is normally a separate equipment finish range. The addition of starches or polyvinyl alcohols (PVA) to the yams acts to strengthen the warps yarns, act as a lubricant, and smooth the warp yarn surface for the violent weaving process, thus reducing physical stress and breakage. Starches most commonly used include potato starch, rice starch, and corn starch, but synthetic waxes and PVA may be employed completely or to complement the starches. The disclosed invention yields greatly improved yam dyeing qualities with all of these common starches, but corn starch is the preferred starch because of the elevated viscosity and improved durability of protective coating of this starch. It is for this reason that the implementation of corn starch alone is not novel, but as it is complementary to the process disclosed, it is an embodiment of the invention when other factors are considered, or when being used with other embodiments disclosed within the invention to achieve improved characteristics of dye penetration, retention, and relative whiteness of core.

[ 0043 ] After immersion in the sizing vat and once again passing through nip rollers, the threads are processed over a series of heated roller drums to dry the individual warp yarns before being separated to be rolled onto loom beams. These loom beams of dyed warp yarns are then woven with the weft yarns respective of the desired look.

[ 0044 ] Yams have now been spun, scoured, rinsed, dyed and oxidized repeatedly, rinsed, treated with sizing, and now woven. Many denim products are completed at this stage. Most are further processed for finishing.

[ 0045 ] Traditional stages of finishing may start with fabric mercerization. Fabric mercerization involves relatively high concentrations of sodium hydroxide caustic (50% NaOH) ~ 300 g/L at -42° Ban me at temperatures as high as 70° C. This high dosage of caustic strips the denim of the previously applied sizing and, depending on application, may provide a luster, as well as added tensile strength to the material. An additional added benefit is that the dye that appears to linger in the core, but is not fasted to the core, appears to be removed, creating a much whiter core.

Traditional mercerization is by itself not novel, but when being used to enhance other embodiments of the disclosed invention it itself becomes a complementary embodiment.

[ 0046] Another mercerization related embodiment involves reducing the

temperature of the caustic solution from the typical -70° C. to a range of room temperature to 50° C. Another benefit of fabric mercerization with this invention is that laser because there is less or no starch to

penetrating into the white core, which is an embodiment. Also, there will be less laser ash, which will be easier to remove in wet processing. In addition to reduction of dwell time and exposure to water, temperature reduction is immensely important as it tends to cause the yarns to more readily accept chemicals such as scour and dye.

[ 0047 ] Another traditional step in finishing involves skewing or torquing the denim fabric. The fabric is exposed to water that is traditionally 45°- 50° C. and then so as to assure that the weft yams are moved slightly diagonal to the sel vedge edges to compensate for natural cotton movement back towards neutral positioning when washed The novelty of the invention can be improved at this stage as well. One embodiment of the disclosed invention is to reduce the temperature of the water used at the skew/torque range stage. Yet another embodiment of the disclosed invention is to skip the skew/torque stage entirely to forgo exposure to the high temperature water.

[0048] Another traditional step in finishing involves sanforization. Sanforization involves the exposure of the denim material to steam or hot (70° or hotter) water before being rolled over a steam heated steel roller while being compressed by a high pressure rubberized roller. The sanforization reduces the warp directional shrinkage experienced in subsequent sewing, industrial wash, wear, or consumer washing. One embodiment of the disclosed invention is to skip sanforization for the sake of furthering the benefits of the disclosed invention by reducing any exposure to water.

[ 0049] After denim is woven at the denim mill, most of it is sent to garment manufacturing. Garment manufacturing involves cutting, sewing and then both dry processing and garment wash procedures. Dry processing is a generic term for a series of processes that involve no or very little water. Dry processing may involve sandblasting (no longer allowed by most labels), hand sanding with sandpaper, laser abrasion treatment, destruction caused by lasers, knives, rotary brushing tools, the application of resin, and bleach rubs as examples. Wet processing typically involves the use of environmentally challenging amounts of water, as well as many chemicals and abrasive substrates such as stones. The inventive concepts introduced for the first time in this invention can dramatically reduce wet process costs from USD $0.50 to USD $1.00 per garment and potentially even greater savings. Reduction in the amount of water, stones, auxiliary chemicals, enzymes, and color reduction agents to wash the jeans to a previously determined standard will he significant and produce new environmental and sustainability benefits the marketplace has been begging for. Additionally the laser and ozone process would be faster to remove indigo and sulfur color from denim produced from this invention because the laser or ozone would not have to penetrate as far into the core, Early results indicate that the time to laser abrade a pair of denim jeans could be cut in half with these inventive concepts.

[ 0050 ] The denim mills, in the attempt to attain the desirable dark colors on their yams, expend vast amounts of energy and chemicals to maximize the penetration and fastness of dyes. Quite often the primary purpose of both wet and dry processing is to remove, lighten, or otherwise alter these indigo and sulfur dyes applied at the dye mill. The disclosed invention involves a reduction in chemicals and water usage at the mill, as well as a savings in energy costs as the various immersion tanks are heated much less or not at all. Hence, these inventive concepts surprisingly reduce costs at both the mill and the garment processing laundry.

[ 0051 ] Traditional methods of scouring and dyeing is focused on opening and penetrating the yarn with dye, but yarn penetration of dyestuffs is unpredictable.

This unpredictability increases with escalated penetration. This has resulted in yet another problem with which the industry struggles . Garments made from traditionally dyed cotton denims often undergo extensive wet processing to selectively lighten the shades. The increasingly unpredictable nature of exaggerated yarn penetration of dye results in yams being dyed with equally exaggerated non uniformity with regards to shape of the dyed areas in comparison to the shape of the yams. Figure 2 is a representation of what yams may look like with exaggerated non-uniformity with regards to the shape of the dyed areas in comparison to the shape of the yams.

[ 0052 ] One issue with the exaggerated, non-uniformity in dye penetration is in dry processing. With a series of yams that, in close proximity, have vastly different levels of dye penetration, attempts at abrasion with sprayed bleach medium, hand sanding, rotary bmshing, laser processing, ozone, or even water jet sprays commonly produce unfavorable results. Some yarns may be abraded in areas that experience 10% dye penetration, and other yarns (or areas of the same yarn) may have dye penetrations as high as 60%. The abrasion process cannot account for

changes in dye penetrations, so some yarns in a particular batch that are supposed to have 50% color reduction may instead experience 80% color reduction, and other yarns may experience no color change at all. This uneven nature of the indigo or sulfur dye penetration and the need to partially expose the white core of deeply dyed warp yams results in damage to the tensile and tear strength of the exposed warp yarns, which decreases overall strength and longevity of the denim garments.

[0053] Another embodiment of the disclosed invention is a dye penetration and fastness that is significantly more uniform. These terms are together purposefully.

Dye penetration that is nonuniform is of little concern when the fastness is uniform. Dye located in areas that lack fastness because of a waxy core rinses off very easily and therefore is insignificant. This uniformity can be understood to mean that the dye experiences both similar penetration and oxidized fixation in a shape that follows the outer surface outline of a given warp yam. Figure 3 is an example of yarns with dye penetration and fixing that follows the outside perimeter of the yarn. An important distinction within this embodiment is that the wash fastness is uniform. Yams processed from the dye range may have cores that have dye present within them, but exposure to caustic immersion, such as in mercerization, or even regular laundering steps will remove dye that is present, but not fixed within the inner portions of the yam. These loose dyes are located in or near the core of the yarn and were not properly attached through oxidation steps to the warp yarn are simply washed away harmlessly and easily. This is in contrast to the traditionally processed yarns where fastness to the portions within the inner areas of the core is more likely and costly to remove for reasons stated throughout this invention disclosure. [ 0054 ] This invention is described throughout the document to involve indigo dye, but the embodiments pertain to other dyes as well, including dyes such as sulfurs, other vat dyes, and other dyes. Sulfur dyes may be introduced within the dye range before the indigo. This is commonly referred to as sulfur bottom, and when paired with the disclosed invention, will provide a largely (>60%) white core. Sulfur dye vats using the disclosed invention are an embodiment and as they use the same sodium hydrosulfide as a reducing agent the conditions are consistent with those disclosed within the invention. The nip pressures and oxidation times disclosed throughout the invention related to indigo are also applied to sulfur and other dyes.

[ 0055] Sulfur dyes may be used after the application of indigo dyes. This is commonly known as sulfur topping. The conditions associated with sulfur top applications pertaining to the invention are consistent with those of sulfur bottom or pure indigo dyeing.

Table 1 below provides much of the information shared across many of the disclosed embodiments.

Table 1. CleanKore vs Conventional Parameters

[ 0056] The inventors believe these embodiments to be revolutionary to the textile industry for a host of reasons. Reduced concentrations of chemicals, paired with overall reduced volume of water involved with dyeing provide much needed relief to industrially taxed water systems. The reduction in chemicals, in addition to fewer and more safe chemicals on many Restricted Substance Lists (RSL), involves savings from the logistics of shipping and storing those chemicals. With lessening chemical harshness of the scour comes the added benefit of lower turnover of the water that is involved because of lowered contamination rates, so easier wastewater treatment for effluent OR re-use in other mill processes. In addition to reducing water and chemicals, a critical cost savings element is time. The reduction in time to achieve a standard wash pattern could be quite dramatic in increasing the number of wash loads per unit of time and thus the throughput of the laundry process.

Associated cost savings could be significant and unprecedented in the industry. [ 0057 ] Increased nip pressures involve greater retention of chemicals used in scouring, dyeing, rinsing, sizing, and fabric finishing operational stages. This novel embodiment alone benefits the process as a whole since lower use of harsh chemicals that must be treated in wastewater facilities.

[ 0058 ] Furthermore, better retention of a white core through embodiments that reduce yam penetration of the dye greatly reduces dependence on chemical and physical methods to remove color to reveal the white core. Uniformity in the shape of the dyed areas of the yarns greatly improves the aesthetics of the denim resulting in far fewer seconds of fabric and garments. Reduction in dye penetration has significant, up to 50%, beneficial impact on the speed and / or efficiency of the laser systems or hand sanding to create the often intricate wear patterns, such as those shown in Figure 1.

[ 0059] In addition to increasing the efficiency of abrasion and wash processes, inventors realized that the disclosed technology could be a contributing factor to the elimination of potassium permanganate. Potassium permanganate (PP) is often used as a localized or global bleaching agent and considered necessary within the fashion industry to counter the excessive dye penetration that the denim industry

conventionally produced. Examples of PP being used as a bleaching agent to enhance abrasion methods can be seen in Figure 4. [ 0060 ] When methods to physically remove indigo to reveal the white core fail,

PP is commonly used. PP is not only dangerous to the laborers that apply it, but it involves additional washing and wastewater treatment steps that result in millions of gallons of water being used annually around the world for this purpose. In addition, the reaction of PP and indigo produces isatin which

[ 0061 ] rapidly form anthranilic acid which in turn yellows along with the article treated. The inventive embodiments disclosed involve a much shallower ring of dye (indigo or sulfur), which is more consistently and successfully removed via conventional garment abrasion methods. Therefore a key benefit and an embodiment of this invention is the elimination or major reduction in the use of PP and the marked cost reduction that results.

[ 0062 ] Summary of these points, along with new additional subject matter follow in the paragraphs below:

[ 0063 ] Increase warp yarn twist multiple of 5.0-5.3 before warp dyeing to increase yarn density, further limit surface area, and tighten yam fiber cable effect.

[ 0064 ] Increase weft/filling twist multiple up to 6 5 for increased design aesthetic that we believe will elevate warp twill line that may increase wash abrasion contrast or yield unique design effect

[ 0065 ] White core technology lends many benefits to the textile mill through cost savings in the reduction of chemical consumption, energy savings with lower temperatures in scouring and oxidation stages, and does so while improving the aesthetics and quality of the product.

[ 0066] The manufacturers of garments and articles produced save significant overhead and chemical consumption during the wet processing stage with the “CleanKore” technology through massively decreased wash-down times. This frees up large, costly washing machines, and space and making great strides in reducing environmental impact.

[ 0067 ] Still, a significant portion of the positive impact this“CleanKore” technology offers the textile industry may come at the dry processing stage. Dry processing traditionally involves heavy implementation of hand sanding operations. Operators labor to abrade garments manually, while loosely following often simplified versions of a designers original pattern. Operator

[ 0068 ] fatigue, repetitive injuries, high employee turnover, inconsistencies between operators, personal protective equipment, health and safety monitoring, and the necessity of potassium permanganate spray, all make hand sanding an expensive necessity in achieving the worn look.

[ 0069] This“CleanKore” technology, paired with RevoLaze's patented laser technology, will change the manufacturing landscape for the better. For decades, lasers, just as laborers, have struggled with traditional dyeing techniques of textile goods. Excessive dye penetration at the mill requires either excessive labor or laser energy to remove the necessary indigo or sulfur dye to reveal the white core. Often times, garments would receive laser treatment but still require PP spray to lessen the effect of the irregularly shaped core and the color retention involved with it.

[ 0070 ] PP spray has been known for decades to be a health hazard to the long term lung health of the operators required to spray and handle it.

[ 0071 ] With“CleanKore” technology, lasers can much more effectively and precisely remove dye from indigo and sulfur-dyed textiles. This increase in efficacy has the potential to eliminate the dependence on PP spray for selective bleaching and also greatly improves the aesthetics of the achievable patterns. A greater reliance on laser will result in designers realizing their designs, patterns, logos, and textures and improve the overall marketability of denim on the whole. It will also positively impact the tear and tensile strength of the fabric after laser etching, because less energy will be required to achieve the worn look. Not since the original introduction of laser to the denim manufacturing world has there been such an exciting and revolutionary opportunity for laborer safety, cost savings, flexibility in dry process design, and an improved product desirability to increase sales. Laser abrading CleanKore fabric is also associated with generating worn patterns with higher contrast vs. laser abrading traditional denim fabric.

[ 0072 ] By preserving a larger percentage of the white core and generating a more uniform shape of the white core relative to the shape of the yarn, this allows improved laser quality, consistency and throughput. The larger percentage of the white warp core allows the laser to penetrate the core faster, and therefore less laser intensity is needed. By having a more uniform shape of the white core relative to the shape of the yarn, when the laser penetrates the core, it will have a much more consistent result throughout the core compared to the standard white core which is more jagged in shape. The concept of this invention is the same throughout. The mill wants the yams dyed to a certain color, but with the least amount of dye penetration as necessary. Achieving this goal results in the mill saving money on chemicals and dye, and the dry processing saves money on laser/hands and energy due to the fact that it takes less effort to reveal the white core the closer to the surface it is, and unimaginable water savings in washing for the same reason.

[ 0073] A major benefit of this invention is that when using the laser technology, it can replace potassium permanganate spray (PP spray), which is a very hazardous and industry regulated chemical. PP spray is used to add brightness or whiteness to the abraded area. Laser etching or hand sanding alone cannot achieve the brightness necessary on normal denim fabric. PP spray also requires additional water and strong neutralization chemicals for its removal. However, by using methods in this invention, it is now possible to replicate the look of PP spray by laser alone. By laser etching on the rigid fabric, it can achieve a similar brightness or whiteness compared to PP spray. For optimal results, laser etching should occur on the washed garment to properly replace PP spray. However, both methods can be used. These results are possible because once the laser penetrates into the dyed warp core, a brightness or whiteness automatically appears, which has a similar look to PP spray. An

embodiment therefore is the improvement of the laser to penetrate the core with the white core technology compared to conventional denim fabric.

[ 0074 ] A critical embodiment is to couple CleanKore with RevoLaze’s LightLaze software, as described in Patent application number 16155203 , filed October 9,

2019; the entire contents of which are herewith incorporated herein. This white core technology invention to give optimal laser etching and product performance results. Since LightLaze enhances the laser file, more high and low contrast differences within the file will be visible on this denim compared to normal denim fabric; and the resolution will be subsequently improved. The details and quality of design will improve on this unique fabric, along with increased laser throughput. Filters incorporated into the LightLaze software will replace hand sand touch ups and give much more detailed textures and hand sand looks with the white core fabric compared to normal denim fabric.

[ 0075] Good results are obtained with increased immersio oxidation ratios as high as 1 : 15.

[ 0076] One embodiment of the invention is an oxidation“skying” range formed of range rollers with dynamic oxidation times. This would involve controlling oxidation times through nonconventional methods, possibly with oxidation rollers that move according to oxidation specification. These oxidation times could be varied through the number of rollers, the distance between the rollers, or similar means.

[ 0077 ] The invention of dynamic oxidation fixation control can allow a mill to have several target shades met through the modification in oxidation time rather than the purging of all dye vats and this is a new embodiment of this invention.

[ 0078 ] The invention of dynamic oxidation times could allow a mill to counter atmospheric conditions, such as temperature, humidity, airflow, dew point etc which can have an impact on the oxidation rate which can have a dramatic impact on the resultant shade. These variables could be accounted for with pre-programmed responses to changes measured by sensors, or modified manually. The invention of dynamic oxidation times could allow a mill to more effectively counter the impact of more or less polluted cotton without having to adjust or purge scouring baths or dye tanks

[ 0079] Typically, coarser yarns have a higher dye pickup rate than finer yams. The invention of dynamic oxidation times could allow a mill to more effectively counter the impact of yarn fineness without adjusting throughput within the dye range, without adjusting the scour bath, or adjusting the dye vats themselves

[ 0080 ] Buffered indigo dye bath pH to 11.0 (lower) and to 12.5 (higher). [ 0081 ] Excellent results can be obtained from the following: : Cooled dye range boxes to further slow indigo penetration into warps with lower temperature— used cooling, such as with dry ice and/or other refrigeration. With dry ice, the nitrogen unexpectedly forced oxygen out of the system to reveal deep shade on thin exterior ring dye. The cooling of dye range boxes including the use of dry ice is yet another embodiment of this invention. Another embodiment is to use traditional

refrigeration techniques would be much more efficient and consistent, consequently more likely.

[ 0082 ] Controlling the actual dye bath temperature continuously could

significantly benefit the throughput of the operation and improve the laydown of the dye on the yarn and this is yet another embodiment of this invention.

[ 0083] Other embodiments include the removal of fabric mercerization completely in final finishing or reducing fabric mercerization by 50% or more in final finishing.

Reduction in mercerization could be attained through reduction in time exposed to chemicals, reduction in chemicals, or reduction in temperature of chemicals.

[ 0084 ] The techniques described herein can be used as part of a conventional ring dye system.

[ 0085 ] Ring dyeing is typically performed using rope dyeing or slasher dyeing methods. Rope dyeing is described in U.S. Patent No. 7,201,780. Yarn is gathered in “ropes”, typically made of 300 to 400 yarns. These ropes (typically 18 to 48 ropes/machine) are sent through a continuous rope dyeing machine made up of one circulating dye bath separated by a number of boxes as shown in Figure 10. The ropes travel through the dye baths for approximately 15 to 20 seconds submerged, allowing soluble leuco-indigo dye to coat an outer layer of color onto the yarn. This yarn then proceeds into a“skying” segment where the soluble leuco-indigo is oxidized rendering it insoluble, adhering the indigo to the cotton yarns by its exposure to air, to create the oxidized blue indigo. The process repeats with successive dye exposure to continue to build color yield on the perimeter of the yam. Dye penetration depths be also controlled with manipulation of the textile auxiliary chemicals in the bath (e.g., caustic (NaOH) or a reducing agent such as sodium hydrosulfite or a sodium borohydride/bisulfite combination. Although there are several critical steps in ring dying and denim mill processing, the inventors believe that the ratio of the time the warp yam spends in the immersion box to the time the warp yam spends in the oxidation segment is one critical factor to achieving different and improved denim fabric characteristics and properties.

[ 0086] Figure 5 shows a diagram of a conventional slasher continuous dyeing machine in which this system can be used and in which oxidation and immersion dye box steps are labeled. As described elsewhere herein, yam 100 is held between idlers 105 as it travels along a path. The path causes the yarn to travel through immersion dye boxes such as 110, which is filled with dye. This allows the leuco- indigo dye in the box 110 to paint an outer layer of color onto the yarn. This yarn is held between idlers 111, 112, 112 in the dye box 110, for a time dependent on the speed of the yarn along the path. The yam then proceeds on idlers 115, out of the box 110, into a“skying” or oxidation segment where the yam is held between idlers over the box, and the leuco-indigo is transformed to the oxidized blue indigo with air. The process repeats, by going through another box 130, to another oxidation 140, and continues, to continue to build color yield on the perimeter of the yam.

[ 0087 ] Although only a few embodiments have been disclosed in detail above, other embodiments are possible and the inventors intend these to be encompassed within this specification. The specification describes certain technological solutions to solve the technical problems that are described expressly and inherently in this application. This disclosure describes embodiments, and the claims are intended to cover any modification or alternative or generalization of these embodiments which might be predictable to a person having ordinary skill in the art. For example, other materials can be used.