Patent Application
20250101675
This disclosure is related to the field of antimicrobial garments, fabrics, filaments, and staple fibers. Particularly to antimicrobial garments and fabrics which obtain their antimicrobial function from plant-based compounds and maintain antimicrobial function through laundering.
The world is full of microorganisms. While many of these are beneficial, or even necessary, for human survival, a large number are, in fact, detrimental and downright dangerous to humans. It has long been recognized that a large number of human maladies can be traced to microorganisms and specifically viruses and bacteria. Maladies such as COVID-19, influenza, malaria, staphylococcus (staph), athlete's foot, and even the common cold can be traced to microorganisms or antigens acting on the human body.
Outside of recognized disease, even more common, but undesirable, conditions such as body odor can be traced to microorganisms. While conditions such as body odor are far from life threatening, they are undesirable and can cause stress and anxiety. As humans are social creatures, body odor which is not controlled is typically considered undesirable and can have major social implications. Further, while odor is essential for scent-based animals to identify each other, as humans are generally considered a sight-based species, the failure to control body odor is often seen as socially detrimental. Because of this, while many may think it is an unnecessary action, reducing the detrimental reactions to body odor is indelibly a part of modern human life.
The origin of human body odor is found in a variety of places. Much of the origin of body odor is associated with sweat, which, while inherently odorless, contains components that are broken down by microorganisms (typically bacteria) on human skin and associated articles in contact with skin (such as clothing) which convert certain proteins to acids. These bacteria, and the chemical process performed, do emit odor. For this reason, areas where sweat is most present (for example the armpits) are both washed regularly, but also often treated with substances to inhibit sweating, to conceal odor, or kill the bacteria present. These substances are often placed directly on the skin but for some people that can lead to rashes and irritation.
Because humans are essentially the only animals that wear clothes, sweat can also become trapped in the fabric of our clothes where microorganism action on the sweat can emit odor. Further, even when the microorganism action takes place on the skin, for certain fibers (particularly synthetic fibers like polyester), these odors can be adsorbed by the fibers and become a component of the fibers. This can cause the fibers to release the odor in later use, even without continued presence of the microorganisms or sweat. Thus, clothes can emit odor when worn, after having been removed, and when worn again. This is well known from the scent of dirty socks in a laundry hamper but is also very common in exercise or workout clothes which often are exposed to greatly increased amounts of sweat.
The primary issue encountered with microorganisms is that they are everywhere, and it is often that these are both beneficial as well as detrimental in some way. Part of the reason humans may find body odor noxious or offensive is because we associate it with potential danger. For example, most humans react negatively to the smell of rotting meat. This could very easily have been a defensive evolution so we do not eat it. Because of this, it is often desirable to simply minimize or eliminate microbial organisms from human contact. While complete elimination of microorganisms in or on humans would typically be fatal, minimizing certain microbial populations in certain circumstances is often beneficial.
Minimizing certain microbial populations can be particularly beneficial in situations where the human body is at an increased risk for infection. This can occur, for example, when the skin is broken (either by accident, or purposefully such as in surgery) or where a human has a decreased immune response due to age, immunosuppressant drugs, or other conditions. It can also be beneficial when the organism is external to our body and may result in unwanted results. This is the case in body odor where, while it is arguably unnecessary and cosmetic, removal can provide increased comfort and decreased stress and anxiety.
At the same time, microbes that can be a source of odor can also be beneficial to the skin. The presence of certain particularly odoriferous microbes on the skin, for example, has been linked to reductions in inflammation, eczema, and certain dangerous infections. For reasons such as these, it is often preferential to keep and protect microorganisms on the skin and reduce odor in other items in contact with the skin (such as clothing) to reduce overall body odor. Thus, fabric treatments that can kill microorganisms in fabric, or can reduce or inhibit release of odors trapped in the fabric, can be a preferable solution to skin treatments.
In order to assist the body in the destruction of harmful or simply annoying microorganisms, a variety of things are used to eliminate microorganisms not from within our bodies, but from around them. Because many forms of bacteria are dangerous, many of these products are specific antibacterial compounds which typically target specific features of bacteria to kill them off before they ever impact our bodies. We are all familiar with antibacterial soaps, hand sanitizers, and the like which are designed to kill bacteria on the hands to inhibit us from transferring them internal to our bodies via touching a body orifice such as by wiping the nose or simply eating. A concern with antibacterials is that while antibacterials can be very effective, they do not kill everything and can have the side-effect of allowing bacteria to evolve which are immune to particular antibacterials. Further, most of them are intended for direct use on the skin and, thus, can destroy beneficial microorganisms as well. For this reason, they are commonly used sparingly as too much use can result in bacteria evolving which are increasingly dangerous to humans and immune from the antibacterial. Further, overuse on the body in places where odor may be more commonly generated, but which are less likely to transfer microbes to an internal area, can do more damage to the beneficial microorganisms than it helps with problematic ones.
Another classification of antimicrobials are disinfectants. Antimicrobials, and specifically, non-specific antimicrobials, can have a major advantage over other antibiotics and other antigen specific compounds in that they often have a much greater lethality which can readily prevent the spread of resistant bacteria. Antimicrobials are particularly effective when they are broad spectrum antimicrobials that do not specifically effect target bacteria, but are generally lethal to a broad spectrum of microscopic life. However, such antimicrobials are usually supplied in small amounts so that while they are highly lethal to smaller organisms, they generally have little effect on megafauna such as humans. Certain antimicrobials, such as chlorine bleach, are so effective that they are readily accepted in widespread use.
The term “antimicrobial,” however, is often also used specifically to refer to products which are really antibiotic. For this reason, materials which are antimicrobial are often referred to based on how they are used relative to humans. For example, human surfaces and materials which are for use on human surfaces (e.g. the skin) are often referred to as antiseptic if they are broadly antimicrobial. Meanwhile, materials which are used to eradicate microorganisms on non-human surfaces are often referred to as disinfectants. Regardless of which term is used, the end result is typically the same. These types of materials are designed to destroy multiple types of microorganisms that they come in contact with. In effect, they are dilute active substances provided at a level which is lethal to microorganisms, but insufficient to affect the humans that use them. For this reason, one must often be careful with disinfectants so that the user does not take them internally or become exposed to them in high concentration.
There are a large number of broad-spectrum antimicrobials known to humans. Products such as chlorine bleach, hydrogen peroxide, forms of copper, silver and zinc which act as a source for ions, alcohols, and iodine can be effective non-specific antimicrobials. The incorporation of these materials into a variety of products has, therefore, become increasingly commonplace. One can buy a plethora of disinfecting wipes, sprays, and sanitizers which include these substances and are designed to destroy microorganisms on the skin or on surfaces.
One area where such antimicrobial incorporation is seeing increased use is in fabrics and textiles. This can include such mundane uses as in socks or undergarments in order to destroy odor causing microbes, or in wound dressings where the human immune response is being given an aid in inhibiting dangerous microbes from entering the human body and potentially causing complications from an injury or medical procedure. Fabrics are a particularly valuable place to position antimicrobials as they are typically positioned close to (and typically on) humans, but do not involve the antimicrobial being placed directly on the skin. That means that the risk from absorption of the antimicrobial through the skin or from skin irritation from the antimicrobial can generally be reduced.
While the benefits of antimicrobial fabrics are becoming increasingly recognized and such products are becoming more and more common, there are also concerns arising about the antimicrobials being used. Many antimicrobials are generated through potentially dangerous chemical processes that can also produce undesirable and potentially toxic waste products.
Further, some utilize relatively rare elements which are in limited supply and can be hard to obtain. Finally, even beyond the antimicrobial itself, the process of binding the antimicrobial to a fabric can also generate harmful waste.
A further problem exists in post-manufacture use in that an antimicrobial may be washed away by necessary exposure or laundering of a fabric. For example, fabric or yarn that has been impregnated with antimicrobials will often have the particles or compounds held within spaces or interstices of the fabric or yarn. If the fabric or yarn is then used to absorb a liquid to expose the liquid to the antimicrobial, the liquid also competes to occupy the same space and interstice and may knock the antimicrobial particles loose so that they free float in the liquid. In some applications (such as in wound dressings), this may be perfectly acceptable or even desirable, but for other uses it can result in displacement of the antimicrobial to a location where it may have environmental impact as well as lessened antimicrobial effect. This can be exaggerated with repeated use and through repeated laundering. This is particularly an issue with the use of antimicrobials in fabric to inhibit body odor as these products are also often heavily laundered as they often become dirtier due to sweat, soiling, and other exposures.
Because of concerns about the long-term sustainability and availability of antimicrobials, there has recently been a push to move away from manmade synthetic chemicals produced via industrial chemical processes, and from antimicrobials produced from mined and non-renewable resources, to using antimicrobials derived from or produced by other organisms. Organisms evolve in response to continued exposure to novel microbes and most produce their own defensive chemicals. These defensive chemicals can be reused by humans and allow for humans to gain the benefit of the organism's evolution against a novel microbe while simultaneously avoiding the need to produce chemicals via industrial processes or from non-renewable materials. To avoid harming megafauna and other larger, and potentially more intelligent, animal species, there has been a particular push to use plant-based or plant-derived products.
Plants have typically been seen as a good source of raw materials. In the first instance, plants occur naturally or spontaneously on the earth and as is often taught in early science classes, are effectively the opposite side of a continuing circle of life to humans and other animals. For example, many people learn in elementary school that humans use oxygen and expel carbon dioxide while plants take in carbon dioxide and expel oxygen. Thus, the two together can create a circular use of resources which is highly sustainable. For this reason, in recent years, there has been an increased push to have plants generate more materials useful to humans. This can encourage the planting and harvesting of plants, which can also be used as a way to sequester human produced carbon dioxide. It can also discourage the harvesting of animals and can discourage more synthetic production methods that often produce toxic, or at least less readily-disposable, by-products.
Humans have always used plants as raw materials. Wood was surely one of mankind's earliest building materials and it is known that many human cultures made fabrics and products from plant fibers. Plant fibers were also used in mined building materials such as clay to strengthen the resultant products. Even today, plants such as bamboo, cotton, wood (cellulose), and hemp are used in huge amounts as sources for fibers, wood is used in building and in the formation of paper, and large numbers of plants are consumed as food. However, in recent times plants have acquired increased interest as sources for alternatives to modern industrially created materials, particularly those from mined ingredients, as the plants can be harvested, used, and then replanted whereas a mined ingredient is removed and cannot be easily replaced when consumed. As an example, paper products (from plants) are beginning to replace plastics (from mined petroleum) which had often originally supplanted the paper products to begin with. Plants are, thus, increasingly being seen as a source for useful chemicals which have otherwise been synthesized or obtained from minerals or similar geologic sources. In these cases, it is not that plants are “more natural” sources, it is that they are seen as “more replaceable” sources.
As discussed above, many antimicrobial compounds are essentially manufactured and many materials that use such compounds can be considered relatively toxic to megafauna as well. As a simple example, household cleaners often incorporate chlorine bleach (sodium hypochlorite), other chlorides, or peroxides which are dangerous at certain concentrations to humans and other megafauna as well as being effective at killing microorganisms. These products often are forced to play a delicate dance of being effective at their primary purpose of eliminating microorganisms, while not being directly dangerous to humans who contact them. In many respects, this is a question of dilution. Further, disposal of used products can also present concerns as they will sometimes remain toxic, they may produce toxic byproducts when reacted in the environment, and their production can create undesirable toxic byproducts.
The joint push for plant-based products and for products which may be effective antimicrobials without having as great a danger to humans has resulted in a push to locate plant-based and plant-produced cleaners and disinfectants. Because plants are typically natural prey to bugs and microorganisms, it has been discovered that many plants that were already in common use by humans for other purposes are highly effective producers of antimicrobials as the plants effectively produced antimicrobial chemicals as part of their own protection. Oils from plants such as cinnamon, lemongrass, basil, lavender, citronella, and tea tree have all provided effective antimicrobials. Further, products such as mustard seed are desired as a human spice precisely because of their evolved toxicity to smaller lifeforms. Further, naturally occurring acids, primarily citric acid and lactic acid, have also proven to be effective antimicrobials.
In many respects, the fact that many plants include natural antimicrobials should be obvious. The human immune system, as discussed above, is built to attack and destroy invading microorganisms and one would expect that plants, and other animals, would do the same. Plants, however, due to their position generally opposite the animals of the earth, provide a particularly intriguing source of raw materials and their defense response is also readily captured from their structure. Typically, it is recognized that keeping the amount of plants and animals on earth in good balance should allow the population of humanity to greatly increase while not reducing the ability of the earth to successfully sustain them. This can be beneficial for everyone (and everything).
The following is a summary of the invention in order to provide a basic understanding of some aspects of the invention. This summary is not intended to identify key or critical elements of the invention or to delineate the scope of the invention. The sole purpose of this section is to present some concepts of the invention in a simplified form as a prelude to the more detailed description that is presented later.
Because of these and other problems in the art, described herein is a process, and the resultant product, for effectively binding plant-based antimicrobials to various fabrics which provides for long term antimicrobial effect of the fabric and the resultant fabric.
There is also described herein a process, and the resultant product, for effectively binding plant-based materials to various fabrics to provide for antimicrobial effect of the fabric. The fabrics and methods will typically maintain microbial reduction characteristics even after repeated laundering.
There is described herein, among other things, a method of forming an antimicrobial fabric (and the resultant fabric), the method comprising: providing an aqueous solution comprising tea tree oil and citric acid. The tea tree oil and citric acid work jointly to provide an antimicrobial effect, but in different formulations their relative percentages can be different. Regardless of chosen relative percentages, it has been found that the combination tends to remain in or on fabric longer than either chemical individually and can provide a much longer lasting antimicrobial effect. In an embodiment, a relatively small amount of the chemicals may be used with an aqueous solution being used to treat fabric that is from 0.01% to 1% tea tree oil and often less than 0.1%, from 0.1% to 5% citric acid, from 0.5% to 15% of a binder, and at least 75% water, by weight. In an alternative formulation, a formulation may be made which is from 1%-20% tea tree oil, from 1% to 20% citric acid, and from 1% to 20% of a binder by weight. In either embodiment, an emulsifier or stabilizer may optionally be included. If included it will typically be from 0.5% to 5%, by weight. The solution is typically used by exposing a fabric to the aqueous solution for a period of time and then drying the fabric after the exposing.
In an embodiment of the method, the binder comprises a polymer that serves to crosslink reactive end groups of the solution to the fabric surface.
In an embodiment of the method, the binder is a biological-based, plant-based, or plant-derived binder. In an embodiment, the binder is polysaccharide-based.
In an embodiment of the method, the exposing includes a wet process with the aqueous solution being applied to the fabric with an application load level of between 1% and 20%.
In an embodiment of the method, the application load level is between 5% and 15%.
In an embodiment of the method, the wet process comprises a continuous “Pad-Dry” process.
In an embodiment of the method, the wet process comprises an “exhaust” process.
In an embodiment of the method, the drying comprises: placing the fabric on a tenter frame containing heating zones which activate the binder.
There is also described herein, in various embodiments, an antimicrobial fabric comprising: interconnected synthetic or natural fibers; the interconnected synthetic or natural fibers having been exposed to an aqueous solution comprising in a first embodiment from 0.02% to 1% tea tree oil, from 0.1% to 5% citric acid, from 0.5% to 15% of a binder, and at least 75% water, by weight. In a second embodiment, the interconnected synthetic or natural fibers have been exposed to an aqueous solution comprising 1% to 20% tea tree oil, from 1% to 20% citric acid, from 1% to 20% of a binder, from 0.5% to 5% of an emulsifier, and from 0% to 5% of a defoamer for a period of time and then dried.
In an embodiment of the fabric, the defoamer comprises an oil-based defoamer made up mostly of petroleum products.
In an embodiment of the fabric, there is included an anti-fungal material preservative.
In an embodiment, the binder may be a biological-based, plant-based, or plant-derived binder. In an embodiment, these may be combined or replaced with a synthetic binder including, but not limited to, acrylic-based or urethane-based synthetic binders.
In an embodiment of the fabric, the emulsifier comprises polyoxyethylene castor oil, ethoxylated castor oil, or polyoxl n castor oil (n=40-60) which may also be included for other purpose in alternative embodiments.
In an embodiment of the fabric, the exposing includes a wet process with the aqueous solution being applied to the fabric with an application load level of between 1% and 20%.
As discussed herein, the terms “thread”, “yarn,” and “fiber” are often used interchangeably although those terms are often provided with specific meaning in the art. However, they are all, in some respects, the act of interconnecting “filaments” to form suitable materials for fabric construction.
Fibers and textiles of fiber includes natural and synthetic fibers and specifically includes, but is not limited to: abaca, acetate, acrylic, alfa, alginate, alpaca, angora, anidex, aramid, azlon, bamboo, beaver hair, broom, camel hair, cashgora, cashmere, chitin, chiengora, chlorofibre, coir, cotton, cupro, elastane, elasterell-p, elastodiene, elastoester, elastolefin, elastomultiester, flax, fluorofibre, glass, guanaco, hemp, henequen, jute, kapok, kenaf, lambswool, lastol, lastrile, llama, lycra, lyocell, maguey, melamine, metallic, modacrylic, modal, mohair, novoloid, nylon, nytril, olefin, other animal hairs, papyrus, pina, polyamide, polybenzimidazole (PBI), polylactic acid (PLA), polycarbamide, polyester, polyethylene, polyethylene, terephthalate, polyimide, polylactide, polyphenylene sulphide, polypropylene, polyurethane, polyvinyl chloride, protein, qiviut, rabbit, raffia, rayon, ramie, rubber, saran, silk, sisal, soy silk, spandex, sulfar, sunn, tencel, triacetate, triexta, trivinyl, vicuna. vinal, vinyla, vinyon, viscose, wool, and yak fibers and/or hairs.
Further “fabric” as used herein will generally comprise any form of material made through the interconnection of any combination of filaments, threads, yarns, or fibers. Although the fabrics may be described as a woven material, this description is not intended to be limited only to weaves and woven material, those are simply a common and well understood example. Materials and fabrics within the scope of this disclosure include without limitation any materials woven, knitted, bound, bonded, crocheted, knotted, tatted, felted, braided, or otherwise formed.
Such materials include fabrics or other materials formed by application of heat and/or pressure to filaments or other materials. For example, and without limitation, this application includes within its scope non-woven materials made to form fabrics that are not woven or knitted, such as felts. Accordingly, as would be appreciated by a person of ordinary skill in the art, the teachings herein are applicable to fabrics made by any method known to persons of ordinary skill in the art. Further, the use of the term “garment” as used herein is primarily to indicate any article of clothing and particularly those constructed from a fabric. However, it should be recognized that the systems and methods discussed herein can be used on other fabric objects which may not be garments such as, but not limited to, industrial fabrics, outdoor textiles, or architectural fabrics, or may be used on fabric objects which may occasionally be used as garments even if it is not their primary purpose.
Essential oils of various plants are used in a large number of human applications. They are commonly used for flavoring in cooking as well as in various skin creams, balms, and salves. In many respects, essential oils can be considered a distillation of the chemical composition of a plant into a particularly concentrated form. Most have a strong scent or taste which is often what they are valued for (for example, vanilla or orange oil), however, it has recently been discovered that many plant oils may have other properties. One interesting plant-based antimicrobial compound is Terpinen-4-ol. It is an isomer of terpinol and a monoterpene and is found in a number of plants including in oranges, mandarins, oregano, New Zealand lemonwood tree, Japanese cedar and black pepper. However, it is most known as being a primary component of tea tree (Maelaleuca alternifolia) oil. Terpinen-4-ol has been placed into a variety of human uses in body products.
While tea tree oil is an effective antimicrobial, its traditional uses are on the skin where it is either absorbed to assist the skin's own auto-defense functions, or is placed into direct contact with microbes whose elimination is desired (such as in the treatment of wounds). In fabric, tea tree oil is generally an ineffective antimicrobial as it is readily removed by laundering and therefore lacks the ability to function over a time of extended use. After as few as ten washings, the effectiveness of tea tree oil treated fabric has typically fallen well below the level as to be effective.
Effectiveness of an antimicrobial is typically measured by its elimination capability. No antimicrobial will completely kill all microbes which it ends up in proximity to, however, a significant reduction in concentration is effectively complete removal as the small amount remaining are typically unable to reproduce fast enough to avoid destruction from a human immune system, or to simply not be noticed (e.g. in the case of odor causing bacteria). Elimination of greater than 99% of a particular form of microbe is typically required for a product to be considered antimicrobial and most actually destroy around 99.9% to 99.99% of such microbes. Tea tree oil can destroy well over 99.9% of bacteria in certain forms and applications. However, after just 25 washings after being placed in or on fabric, its effectiveness can have fallen to as low as 65% which is, most all intents and purposes, sufficiently low as to have no noticeable antimicrobial effect.
Citric Acid is also known to be an antimicrobial although it is more commonly used as a pH adjuster, chelating agent, or preservative in various cleaners. Citric Acid is primary encountered naturally in citrus fruits (such as lemons, limes and oranges) and it is what gives them their tart sour flavor. However, it may be produced at large scale via molds or through certain synthesis reactions. Citric acid is naturally produced in a large number of plants as citrate, which is a primary part of the TCA cycle present in the central metabolic pathway.
In order to provide for an effective antimicrobial fabric which obtains its antimicrobial properties from plant-based materials, it is desirable to provide a blend of citric acid and tea tree oil. The blend will typically be provided to the fabric or to the underlying yarns as a topical treatment where it can be bound to the fabric or yarn via a binding agent. This will typically occur once the fabric has been constructed into a garment but may occur at the fabric or thread stage. The fabric to which it is applied may be natural (e.g. wool or cotton) or may be from synthetic fibers (such as polyester or spandex). The synthetic fibers may be virgin fibers or may be recycled from other materials. In an alternative embodiment, if the fabric is intended to have antimicrobial properties when manufactured, the binding agent may be included as part of such synthetic fibers during manufacturing to prepare the yarn or fabric for exposure to the tea tree oil and citric acid blend. This is, however, generally not preferred.
Synthetic fibers are particularly common in exercise clothing due to their light weight, quick dry, stretchability, and skin hugging capability. As this type of clothing is also one which is commonly exposed to large amounts of sweat, it can also be associated with substantial odor between launderings. Further, injuries during exercise and sports can also regularly occur which can make microbial colonies in exercise clothing particularly dangerous. For at least these reasons, providing antimicrobial capability to fabric including synthetic fibers (either alone or in combination with natural fibers) can be particularly valuable. However, synthetic fiber-based fabrics can also be more difficult to effectively impregnate with other materials due to the structure of synthetic fibers when compared to more naturally occurring fibers.
U.S. patent application Ser. No. 17/734,784, the entire disclosure of which is herein incorporated by reference, provides for systems and methods of producing an antimicrobial fabric, along with the resultant fabric, that utilizes a combination of citric acid and tea tree oil to provide antimicrobial efficacy which is resistant to removal in washing. The mixture will typically be applied in an aqueous solution in the same manner as a fabric dye or treatment with the solution acting as the liquor bath in the treatment process. The solution may comprise, in an embodiment, from 1-20% tea tree oil, from 1-20% citric acid, from 1-20% binder, from 0.5%-5% emulsifier, and from 0%-5% defoamer, by weight with the remainder of the solution comprising water.
It has further been determined that substantially smaller amounts of both the tea tree oil and the citric acid may be used and still produce an effective antimicrobial fabric. Specifically, the antimicrobial effect can be obtained with greater reliance on the inclusion of citric acid as the primary antimicrobial agent with a tea tree oil compound acting as more of an excipient in the resultant coating making the antimicrobial effect of the citric acid more pronounced. Alternatively the tea tree oil may act as a binder in the binding of the citric acid to the fabric or may fulfill both the role of excipient and binder to a greater or lesser degree. In embodiments of such an alternative formulation, the antimicrobial bath is comprised of an aqueous solution comprising from about 0.01% to 1% tea tree oil which will often be in the form of a tea tree oil compound which may be from about 1% to about 5% of the resulting bath. In an embodiment, the tea tree oil compound may be a micro-encapsulated form of tea tree oil. The bath will typically comprise from 0.1% to 5% citric acid which may also be provided in the form of a compound, from 0.5% to 15% of a binder, and at least 75% water. Typically, the remaining ingredients may be standard additions for chemical materials such as stabilizing materials, preservatives, and materials to alter the chemical handling of the antimicrobial formulation. In an embodiment, the tea tree oil may be provided in the form of a micro encapsulation.
The treatment solution will be applied to the fabric via any form of fabric wet process methodology. Typically, the solution will be applied to the fabric with the specific application load level of the solution being around 1-20% with 5-15% typically being more preferred. However, the specific amount of solution used for a fabric may depend on the particular type of fabric, and the specific fiber content of the fabric to which the solution is being applied, as well as the treatment methodology used. In many cases, the fabric will comprise a fabric including both synthetic and natural fibers in combination. However, such solutions may also be used on fabrics formed of purely synthetic fabrics (either of uniform fiber type or with combinations of fibers of different types) or on fabrics including only natural fibers (again including those of uniform fiber type or with combinations of fibers of different types).
In an embodiment, the fabric would be treated using a continuous “Pad-Dry” method for fabric finishing as that term is commonly understood by one of ordinary skill in the art. In such a method, a continuous roll of fabric would typically be immersed in a trough containing a particular strength of the antimicrobial solution and then padded through rubber squeeze rollers (also called a mangle or wringer) to impart a consistent wet pick up level. The pad operation is normally on the entry end of a tenter frame which contains heating zones used to dry the fabric and impart durability from activating the binder.
Alternatively, the fabric may be treated using the “exhaust” method of wet processing where a certain weight or length of fabric (a “batch”) will typically be placed within a bath of the solution (liquor) and “exhausted” on to the fabric at elevated temperatures for a specified period of time before it is removed. The fabric is then run down the tenter frame as previously mentioned to dry the fabric and impart durability. Exhaust methods typically utilize a jet machine but can be accomplished by other machines such as a jigger, winch, beam, or garment machine. As previously mentioned above, the specific application load level of the solution in any of the above methodologies will typically be within the same 1-20% and often within 5%-15%.
The binder present in the solution can comprise a variety of binders and/or binder packages (including, for example, a bunder and cross-linking agent in combination) and essentially serves to provide chemical attachment to the surface of the fabric to impart further durability for maintaining the citric acid and/or tea tree oil to the fabric through extended laundering cycles. The binder, in an embodiment, will be a polymer that serves to crosslink reactive end groups of the solution to the fabric surface. While a variety of binders can be used and may be altered depending on the composition of the substrate fabric, in order to provide a more biological-based bath, the binder may comprise a biological-based, plant-based, and/or plant-derived binder or binder blend. In an embodiment, the binder may be a polysaccharide-based binder. The binder may be activated by heat in the drying process or via another mechanism.
The emulsifier or stabilizer present in the solution will often act as a rheology modifier and can comprise a variety of emulsifiers and/or stabilizers and is primarily included to provide viscosity and stability to the solution as would be understood by a person of ordinary skill in the art. At the same time, inclusion of a emulsifier of certain types could improve retention of the tea tree oil and citric acid combination in the fabric. The emulsifier, in an embodiment, will be a non-ionic surfactant such as those typically used in dyeing or other aspects of the manufacture of fabric and may have a pH of about 5.5 to about 8.0 (in 5% solution). In an embodiment, the emulsifier comprises polyoxyethylene castor oil, ethoxylated castor oil, polyoxl n castor oil (n=40-60), or any similar compound or combination of compounds. In an alternative embodiment, such compounds could be included for alternative effect including to directly provide for additional anti-microbial capability.
The defoamer, if present in the solution as it is optional, can comprise a variety of defoamers and/or antifoamers and is primarily included to provide for foam control during processing as would be understood by a person of ordinary skill in the art. In an embodiment, the defoamer will comprise a nonionic non-silicone defoamer for aqueous solutions. This will often comprise an oil-based defoamer made up mostly of petroleum products, but oil-based materials may also be based on synthetic oils, vegetable oils, or other oils. The defoamer will typically have a pH of about 6.0 to about 7.0 in 2% solution
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The qualifier “generally,” and similar qualifiers as used in the present case, would be understood by one of ordinary skill in the art to accommodate recognizable attempts to conform a device to the qualified term, which may nevertheless fall short of doing so. This is because terms such as “circular” are purely geometric constructs and no real-world component or relationship is truly “circular” in the geometric sense. Variations from geometric and mathematical descriptions are unavoidable due to, among other things, manufacturing tolerances resulting in shape variations, defects and imperfections, non-uniform thermal expansion, and natural wear. Moreover, there exists for every object a level of magnification at which geometric and mathematical descriptors fail due to the nature of matter. One of ordinary skill would thus understand the term “generally” and relationships contemplated herein regardless of the inclusion of such qualifiers to include a range of variations from the literal geometric meaning of the term in view of these and other considerations.
While the invention has been disclosed in conjunction with a description of certain embodiments, including those that are currently believed to be useful embodiments, the detailed description is intended to be illustrative and should not be understood to limit the scope of the present disclosure. As would be understood by one of ordinary skill in the art, embodiments other than those described in detail herein are encompassed by the present invention.
Modifications and variations of the described embodiments may be made without departing from the spirit and scope of the invention.
It will further be understood that any of the ranges, values, properties, or characteristics given for any single component of the present disclosure can be used interchangeably with any ranges, values, properties, or characteristics given for any of the other components of the disclosure, where compatible, to form an embodiment having defined values for each of the components, as given herein throughout. Further, ranges provided for a genus or a category can also be applied to species within the genus or members of the category unless otherwise noted.
This Application is a Continuation-In-Part (CIP) of U.S. patent application Ser. No. 17/734,784, filed May 2, 2022, which claims the benefit of U.S. Provisional Patent Application Ser. No. 63/182,548 filed Apr. 30, 2021. The entire disclosure of all the above documents is herein incorporated by reference.
| Number | Date | Country | |
|---|---|---|---|
| 63182548 | Apr 2021 | US |
| Number | Date | Country | |
|---|---|---|---|
| Parent | 17734784 | May 2022 | US |
| Child | 18965738 | US |
