US20150361595A1

US20150361595A1 - Antimicrobial Multicomponent Synthetic Fiber and Method of Making Same

Info

Publication number: US20150361595A1
Application number: US14/302,050
Authority: US
Inventors: Jeffrey Keane; Jon Pavlansky; Greg Gianforcaro
Original assignee: Noble Fiber Technologies LLC
Current assignee: Noble Fiber Technologies LLC
Priority date: 2014-06-11
Filing date: 2014-06-11
Publication date: 2015-12-17

Abstract

A method of producing synthetic threads and yarns which utilize a multicomponent structure having silver in an external sheath. The threads and yarns are then texturized via a false-twist process to increase the amount of silver available at the exterior surfaces of the threads and yarns. The resultant yarns and threads are also provided.

Description

BACKGROUND OF THE INVENTION

1. Field of the Invention
This disclosure is related to the field of antimicrobial fibers, threads, and yarns. Particularly to antimicrobial multicomponent filament and filament bundles utilizing polymer materials in a multi-component construction.
2. Description of the Related Art
The world is full of microorganisms and 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 influenza, malaria, staphylococcus (staph), athlete's foot, and even the common cold can be traced to microorganisms or antigens acting on the human body. Further, even more common conditions such as body odor can be traced to microorganisms. The primary issue encountered with microorganisms is that they are everywhere and it is often difficult to separate the good from the bad. This can be particularly true in situations where the human body is at an increased risk for infection. This can occur 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.
The human immune system is incredibly effective at destroying dangerous microorganisms and supplies a multitude of different responses and attacks when the body is invaded by a non-recognized microorganism. However, even with this powerful response, there are microorganisms that the body can, and regularly does, miss. There is also the issue that while the body may respond to the presence of an antigen, the body may be unable to react fast enough to prevent the human host from suffering permanent injury or death.
In order to assist the body in the destruction of harmful microorganisms, a variety of things are used. Many of these are antibacterial compounds which target specific features of bacteria to kill them off. These are commonly used in conjunction with the human immune response to result in bacterial death. A concern with antibacterials is that while antibacterials can be very effective, they can have the side-effect of allowing bacteria to evolve which are immune to particular antibacterials. For this reason, they are commonly used sparingly.
Another classification of assistance devices are antimicrobials. Antimicrobials, and specifically, non-specific antimicrobials, have a major advantage over most antibiotics and other antigen specific responses in that they often have a much greater lethality which can readily prevent the spread of resistant bacteria. Certain antimicrobials (such as chlorine bleach) are so effective that they are readily accepted in widespread use.
Silver metal, silver nitride, and other forms of silver which act as a source for silver ions, can be effective non-specific antimicrobials. It is understood that the silver ion deactivates structural and metabolic membrane proteins, which will lead to microbial death and many microbes view certain forms of silver as a food source, allowing the silver ion to enter the microbe easier. The incorporation of silver and certain other antimicrobial materials into a variety of products has, therefore, become increasingly commonplace. One problem with silver as an antimicrobial, however, is that it is relatively expensive, and, in order to be effective, the silver particle (or silver ion) needs to be capable of being in contact with the microbe.
One area where silver 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 microbials, 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.
Traditionally, in order to provide for silver textiles, the textile thread or resultant textile product is essentially soaked in silver particles or otherwise coated with a thin film of metal. This film adheres to the thread or textile through a variety of forces such as electrostatics or by becoming wedged in small openings. While this is effective to get silver into the fabric and/or thread, it has a number of downsides. The most major of which is that the presence of silver can result in a discoloration or other modification of the fabric. For example, coating a thread with silver will generally make a silver thread. This can be visible in a resultant article of manufacture which may be undesirable.
A further problem with post-manufacture silver exposure is that the silver may be washed away by necessary exposure or laundering. For example, fabric or yarn that has been impregnated with silver may have the silver particles held within spaces or channels of the fabric or yarn. If the fabric or yarn is then used to absorb a liquid to expose the liquid to the antimicrobial silver, the liquid also competes to occupy the same space and channels and may knock the silver particles loose so that they free float in the liquid. In some applications, this may be perfectly acceptable, but for other ones it can result in displacement of the silver to a location where it's effect is lessened and can result in the antimicrobial effect being decreased with use, such as through repeated laundering.
In order to improve their holding power for silver, some threads are manufactured with silver particles placed directly into the material prior to thread formation. While this does not work for many natural threads unless the silver is spun into the thread with the fibers, it can work for a variety of synthetic polymer threads such as polyester and Nylon where small particles of silver are added to the polymer melt from which the original filaments are extruded and then spun into filament bundles. This allows for the silver to actually be contained as a part of the thread itself which inhibits it from separating from the fabric made from the thread.
While this internal assembly provides for a number of benefits, it also creates some additional problems. For one, the silver is expensive compared to the polymer and it must end up in physical contact with material to which the fabric is in contact to be effective. In many cases, where particularly small silver particles are used, the silver may be small enough to be entirely encased within the thread. In this case, the silver particle provides no benefit. This effect is obviously increased as smaller particles relative the size of the thread are used. However, with larger particles, the thread may have less structural integrity, the silver itself has less available surface area (nullifying cost benefits), and the thread may be unsuitable for particular tasks.
In manufacturing antimicrobial threads which will be formed into antimicrobial fabrics, there is a benefit to maximizing the surface exposure of silver on the thread and minimizing the amount of silver that is entirely within the thread. For polymer threads which are manmade, this can be accomplished through the process of co-extrusion.
In co-extrusion, the filament is made from two different materials. One of these materials includes silver, while the other does not. The latter is used as the core of the material to provide much of the strength and volume, while the other is used to maximize surface exposure. Some such arrangements are described in U.S. patent application Ser. No. 13/006,686, the entire disclosure of which is herein incorporated by reference. In this case, silver contact can be maximized while reducing the amount of silver used in the resultant thread as non-reactive components do not include any silver.
While these types of threads offer some potentially significant reductions in silver usage (and thus cost of manufacture) they can still have problems. In the first instance, the silver exposure is not necessarily maximized as some silver is still encased in the body of the sheath. Secondly, the silver presence can often result in the discoloration of the underlying thread. For example, the presence of significant amounts of silver in Nylon threads can result in the Nylon thread yellowing. This can result in in not being able to hold dyes as well and resulting in a less attractive thread and product. This can in turn mean that the total amount of silver used is reduced.

SUMMARY OF THE INVENTION

The following is a summary of the invention, which should provide to the reader a basic understanding of some aspects of the invention. This summary is not intended to identify critical elements of the invention or in any way to delineate the scope of the invention. The sole purpose of this summary is to present in simplified text some aspects of the invention as a prelude to the more detailed description presented below.
Described herein, among other things, is an extruded filament which comprises a polymer core and sheath where the core is substantially free of silver and the sheath includes silver. Filament bundles formed from the filaments, or the filaments themselves, are texturized to force silver particles to the surface of the sheath, and/or lightly damage the exterior surface of the sheath, to embed the silver particles where their exposure to the exterior surface is increased. This is particularly useful for Nylon filaments but can be used in any polymer filament forming a synthetic yarn. The filament bundles can also be texturized to open the filament bundle further increasing silver exposure.
In an embodiment there is described herein a multi-component filament comprising: a core; and a sheath, said sheath surrounding said core and including antimicrobial particles therein; wherein said filament has been texturized by a false-twist process, said false-twist process increasing the amount of antimicrobial accessible at an exterior surface of said sheath.
In an embodiment of the filament, the core comprises Nylon.
In an embodiment of the filament, the sheath comprises Nylon.
In an embodiment of the filament, the core comprises polyester.
In an embodiment of the filament, the sheath comprises polyester.
In an embodiment of the filament, the antimicrobial particles comprise silver metal.
In an embodiment of the filament, the antimicrobial particles comprise silver glass which may comprise glass particles coated with silver or glass particles including silver nitrate.
In an embodiment, a plurality of the above filaments are bundled together into a filament bundle or yarn.
There is also described herein a filament bundle comprising: a plurality of filaments, each of said filaments comprising: a core; and a sheath, said sheath surrounding said core and including antimicrobial particles therein; wherein said filament bundle has been texturized by a false-twist process to increase the amount of antimicrobial accessible by a fluid in exterior surface contact with said filament bundle.
In an embodiment of the filament bundle, the core comprises nylon.
In an embodiment of the filament bundle, the sheath comprises nylon.
In an embodiment of the filament bundle, the core comprises polyester.
In an embodiment of the filament bundle, the sheath comprises polyester.
In an embodiment of the filament bundle, the antimicrobial particles comprise silver metal.
In an embodiment of the filament bundle, the antimicrobial particles comprise silver glass which may be glass particles coated with silver or glass particles including silver nitrate.
There is also described herein a method of metalizing a synthetic filament bundle, the method comprising: providing a plurality of synthetic filaments, each of said filaments comprising: a core; and a sheath, said sheath surrounding said core and including silver particles therein; texturized said filament bundle by a false-twist process to increase the amount of silver accessible by a fluid in exterior surface contact with said filament bundle.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 depicts an embodiment of a multicomponent filament, specifically a bi-component filament, comprising a core and sheath with silver particles or other sources of silver ions embedded in the sheath.

FIG. 2 depicts an embodiment of a multicomponent filament, specifically a bi-component filament, with silver particles in the sheath where a yarn including the filament has been texturized to expose additional silver.

FIG. 3 depicts an embodiment of a “fiber bundle” comprised of multicomponent fibers with silver particles showing opening of the bundle via texturing to expose additional silver.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT(S)

Because of problems in the art of forming yarns including sources of silver ions, there are described herein multi-component synthetic filaments including an antimicrobial such as a source of silver ions which utilize texturizing to increase antimicrobial exposure.
Texturizing is a process whereby partially oriented filament yarn (commonly called POY) or Fully Drawn Yarn (FDY) is stabilized through heating and drawing. This produces a crimped continuous filament yarn or Draw Textured Yarn (DTY). All types of synthetic yarns can be textured and polymer filaments and filament bundles such as, but not limited to, Nylon and polyester, are typically texturized with texturized Nylon used primarily in the production of ladies' hosiery although it has become much more common in a variety of other areas recently. Texturized polyester is used in various apparel and home furnishings products and, to a lesser extent, in industrial fabric. There are two types of common texturizing machines. As understood by one of ordinary skill in the art, the most common texturizing is provided by false-twist texturizing machines which serve to both twist the yarn one direction, and then twist it back. The resulting yarn is therefore not “twisted” in the conventional sense, but has still undergone a twisting process and that tends to emulate a real twisted or spun yarn and provides some material memory to the yarn.
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. The reason for this is because the process discussed herein can be used to produce any of these items. For the most part, however, this disclosure will focus on the production of “filaments”, which will be considered single strand synthetic fiber or polymer extrusions, and “yarns” or “filament bundles” which are structures comprising a number of filaments combined together. For example, filaments which are spun or otherwise interconnected, entangled, or arranged together form a filament bundle or yarn.
Filaments are generally formed by the melting of polymer pellets or another source of polymer which is then forced through an extrusion die to produce a continuous fiber. A filament can be a single continuous extrusion, or may be a chopped apart extrusion such as to form a staple. This fiber can then be texturized directly (which is uncommon), or can be combined with other filaments to form a filament bundle with the resultant filament bundle can then be texturized.
It is important to recognize that the texturizing process's effect on a yarn can be two-fold. It serves to both modify the structure of the yarn itself (the relationship between filaments in the bundle) and the structure of each filament. For this reason, this disclosure discusses modification of the filament as occurring on a single filament. While the modification may occur on a single filament (e.g. a filament which is not in a filament bundle), this disclosure contemplates that it may also occur on some or all of the filaments within a filament bundle. Further, this disclosure contemplates that the modifications to filaments within a filament bundle may occur in different amounts or at slightly different times depending on the nature of the texturing occurring and the specific arrangement of filaments in the filament bundle
FIG. 1 provides for an embodiment of a polymer filament (100), formed from a synthetic material such as, but not limited to, polyester, Nylon (polyamide 6 or polyamide 6,6), another polymer or combinations thereof. The filament (100) generally has a multicomponent structure including at least two, and potentially more, distinct regions. In particular, the filament (100) of FIG. 1 comprises a bi-component filament formed from an inner core (101) which is surrounded by an outer sheath (103) although side-by-side (adjacent) structures and other shapes and structures, such as, but not limited to, those that are not rounded in cross-section can also be used.
These two components of the filament (100) are generally formed by co-extrusion, although alternative manufacturing techniques can be used in alternative embodiments. When formed via co-extrusion, the inner core (101) is effectively extruded from a first material supply while the sheath (103) is extruded simultaneously, and in relative position to the core (101), from a second material supply. Thus, it is possible to manufacture the filament (100) from two different materials in a single step or from two different sources of the same material. The materials used will generally be synthetic polymers suitable for thread-making.
In a preferred embodiment, the underlying polymer materials will be the same, e.g. both the core (101) and sheath (103) will be of the same polymer (e.g. polyester or Nylon) but this is by no means required. Alternatively, the core (101) and sheath (103) will generally comprise different materials. However, regardless of their respective base materials, the material of the sheath (103) will include an additive therein that is generally not present in the material of the core, or is present in the core in a far smaller percentage. The additive will comprise an antimicrobial material and generally a particulate silver (301) material acting as a source of silver ions. The silver (301) can be in metallic form, or can be included within or on another material, but it ultimately will be provided in the form of a generally solid particulate. In an embodiment, the silver (301) is provided in the form of silver glass. Generally, a majority of the material in the multi-component filament will be in the core and the core may comprise 50% or more, 60% or more, 70% or more, 80% or more or 90% or more of the multi-component filament, but this is by no means required.
Silver glass comprises small beads of glass which may either be coated or partially coated with silver metal, or which may include silver as a metal (either internally or as a coating) or as a compound of silver, for example silver nitrate or nitride, within their structure in such fashion that silver ions are available at the glass surface and the silver glass acts as an antimicrobial. Silver glass is a product well understood by those of ordinary skill in the art and is available in a variety of sizes, shapes, and compositions such as, but not limited to, products produced by Potters Industries, LLC.
As can be seen in FIG. 1, upon extrusion, the silver particles (301) will generally be positioned in one of three positions. Firstly, some of silver (301A) will either be positioned at the exterior surface (105) of the thread either extending outward from the exterior surface, flush with the surface, or otherwise in position that the silver ions can exit the exterior of the thread. Depending on the form of silver (301) used and properties of the polymer, this can allow the silver (301A) to be below the level of the exterior surface (105), while still providing exterior ions. The specific distance may depend on the polymer's hydrophilicity (e.g. absorbency) with water.
Secondly, some of the silver (301B) will generally be positioned entirely within the sheath (103). This silver (301B) is not in contact with any surface of the sheath and sufficiently internal that it generally cannot supply silver ions to a material exterior of the sheath (103). Finally, some of the silver (301C) will be in contact with the interior surface (113) of the sheath and thus in contact with the core (101). In most cases, the silver (301C) will not be entirely within the core (101) as the core initially included no silver (301), but it is possible that a significant percentage of the silver particle (301C) could extend beyond the sheath (103) and either be located in a void between the core (101) and sheath (103), or extend into the structure of the core (101). When the filament (100) is formed by co-extrusion of similar underlying materials, the later would be the expected case as the dividing line (interior surface (113) of the sheath (103)) between the core (101) and the sheath (103) would generally not be immediately clear.
As should be visible from FIG. 1, to the extent that this filament (100) is to be used in an antimicrobial yarn or textile, only the silver (301A) which is in the first position, that is having at least a portion of this structure in ionic transfer with something outside the exterior surface of the sheath (103), has any chance of providing antimicrobial properties to the filament (100). As the silver (301) would need to be able to transfer ions to the microbes in order to kill them, silver (301B) and (301C) which is buried within the filament (100) simply cannot have ion-transfer with a microbe and thus cannot produce any significant antimicrobial effect.
It should be apparent from the discussion of FIG. 1 that in order to provide for a certain level of antimicrobial effect, a certain amount of silver (301A) needs to be present at the exterior surface (105) of the sheath (103). To the extent this needs to be increased, the prior methodology was simply to increase the amount of silver (301) present in the sheath (103) material. As this amount went up, the amount at the exterior surface (105) would necessarily increase proportionally.
The problem with simply increasing the amount of silver (301) used is that silver (301), as a precious metal, is quite expensive compared to the polymer making up the thread (100). Thus, a need to increase the antimicrobial capacity of a thread (100) three-fold could result in a significant extra expense since as little as one-third of the silver (301) used may be present on the outer surface. Further, if too much silver (301) was placed in the sheath (103), the silver (301) could affect the properties of the thread (100). Most notably, with Nylon threads, a greater percentage of silver (301) could result in a discoloration of the thread (100) with it tending to appear more yellow.
The discoloration can present a number of major problems. In the first instance, it can make the thread (100) appear to be old or brittle, which can lead to it being less marketable. In a second instance, the silvered Nylon was often unable to take on dye as well as white nylon and resulting colored threads or fabrics often could not be provided with particular color combinations or results. Because of this, most synthetic threads and yarns which include silver are made from polyester. Silvered Nylon was generally only produced by coating the Nylon in silver (giving it a metallic silver color). While this is superb for certain applications, it is not useable in a variety of others.
In the present arrangement, by having a reduced amount of silver particles (301) in the sheath (103), and then by shrinking the relative projection of the sheath (103) to the core (101) the yellowing can be substantially reduced. In particular, Nylon is generally semi-translucent, thus, as the sheath (103) is decreased in proportional volume, its thickness is reduced allowing more light to pass through and the core (101) to be more visible. As the core (101) includes essentially no silver, its white appearance (which can be changed or altered by dye) will serve to “whiten” the filament (100) as a whole.
While the multicomponent filament (100) of FIG. 1 manages to create a significant improvement on the amount of silver (301) needed without further modification, since no silver (301) is provided as part of the core (101) material, the necessity of having to have the sheath (103) have a definitive thickness still means that not all silver (301) of the sheath (103) material is generally useable. Further, while the silver (301) particles are often very small (being on the general scale of 1-5 microns in an embodiment), it is generally a manufacturing reality that the sheath (103) cannot be made sufficiently thin so as to be less than the diameter of the silver or silver glass particles (301) used. Specifically the filament will often be on the order of 100 microns to a millimeter in diameter with the sheath comprising from 10% to 50% of the total diameter.
In order to increase the silver (301) percentage accessible at the exterior surface (105) of the sheath (103), the filament (100) of FIG. 1 is textured, generally using a false-twist texturing process which is performed on the filament bundle or yarn (300). In this process, a continuous run of yarn is drawn through a rotating die, belt, or similar structure which serves to twist it (generally in the manner of a helix). This is commonly done under heat in order to allow for thermosetting of the yarn (300). Once the yarn (300) has passed the rotation, it continues to be drawn. However, because the yarn (300) is drawn after the rotating die, the yarn (300) after the die is effectively rotated in the opposite direction to the same yarn (300) prior to the die. This serves to effectively untwist it so that at the end of the process, the filaments (100) making up the yarn (300) have been twisted and untwisted by essentially the same amount. Thus, as opposed to a real twist process, where the yarn (300) is actually twisted, the yarn (300) really has no resultant twist. However, it has been observed that the twist is still visible and thus the filament (100) has been structurally altered by the process. Specifically, each filament in the yarn (300) is twisted (and untwisted) to some extent resulting in a filament with some “memory” of twisting. Further, each filament (100) is drawn or “stretched” by the texturing process reducing its mass in any given length (denier).
In addition to texturing the filament (100) using the false-twist process, it is also the case that a filament bundle (300), made from a plurality of filaments (100), that has been texturized alters the arrangement between the filaments (100). This can also improve the reactivity of a resultant yarn. Specifically, in texturing a filament bundle (300) the component filaments (100) will tend to pull from each other and the bundle (300) will open or “fluff-up.” This process is often referred to as “entangling” and may result from blowing air on the filaments. Thus, external surfaces (115) of the component filaments (100) are generally more exposed as they are not interacting with each other. This can result in an increased surface area of available silver (301). This is illustrated in FIG. 3.
It has, however, been determined that running a multicomponent thread (100) through a false-twist texturing process will cause the percentage of silver (301) accessible at the exterior surface (115) to increase as compared to a non-texturized multicomponent thread including an identical amount of silver by a greater amount than is to be expected solely by opening the filament bundle (300). Without being bound by any particular theory of operation, it is believed this is caused via multiple potential structural changes to the filament (100). The first of these is because the false-twisting process acts like the effect of wringing a fabric. In particular, as the filament (100) is initially twisted, components of the filament (100) are pushed closer together. Generally, the interior of the filament (100) is more crushed by this process that the outer surfaces of the filament (100) due to the conservation of angular momentum.
As the multicomponent filament (100) core (101) is twisted, the core (101) will simply compress eliminating any space within the components of the core (101). As the core (101) includes no additives, it will simply twist as expected. Further, as the twist occurs, the inclusion of heat will generally exceed the glass transition temperature of the polymer, but will generally not surpass the melting temperature of the polymer. This is believed to allow for material within the polymer of the core (101) to move within the core (101) as the molecular chains of the polymer are allowed to move past each other. The outer sheath (103) reacts similarly. However, the outer sheath (103) includes the silver particles (301) which are essentially contaminants in the flowable polymer. As the silver particles (301) are still a solid, these particles (301) are not affected by the heat but are now present in an environment where the polymer can more readily flow.
It is believed that as the filament (100) is twisted, particles (301) which are in the sheath (100) (e.g. particles (301B)) will generally be forced upward (more exterior) in the sheath (103). This likely occurs because the material of the sheath (103) which is more interior will be more tightly compressed than that toward the exterior. Thus, the inner layers are progressively more dense. As the silver particle (301) is generally rigid within the viscous liquid environment, it cannot crush under the twisting action and will instead seek to move through the structure of the filament (100) toward the exterior surface (105). In effect, the polymer will flow around the particle (301) and toward the interior of the filament (100). Thus, silver particles (301B) and (301C) in the interior of the sheath (103), or on the interior surface (113) of the sheath (103), will generally be pushed more toward the external surface (105).
Thus, once twisted, particles (301B) which were near the external surface (105), but still too far away to be reactive, will be pushed into proximity with the exterior surface (105) and may be pushed to a point where they are now capable of ion transfer with an exterior compound. In the false twisting process, once the twist has been completed and is being reversed, the filament (100) has been thermoset and the silver particles (301) will be held more rigidly because the flowable nature of the polymer is decreased. However, even if this is not the case, as the filament (100) is untwisted, the silver particles (301) will generally have no reason to move back toward their initial position and will instead remain in the later position migrated toward the exterior surface.
Secondly, it is believed that the texturing process reduces the diameter of the filament (100). Specifically, it has been observed that a yarn which has been texturized has a lower denier than the same yarn prior to texturizing. Thus, as the material flows, the yarn is clearly gaining length. It is theorized, that the texturizing process will likely cause the sheath (103) to both thin out (increasing the silver in ionic transfer distance) and become “damaged.” By damaged, the sheath (103) will have an increase in cavities, voids, holes, and other related structures which will generally increase its effective surface area. The presence of these structures (401) will exposure further internal silver as indicated in FIG. 2.
Once the texturing process is complete, it should be apparent that a greater percentage of silver particles (301A) is now in proximity to or extending from an exterior surface of the filament (100) than was prior to texturing. Thus, the silver reactivity and antimicrobial effect of the thread has increased without altering the amount of silver present. This is generally shown by comparing FIG. 1 to FIG. 2.
While the above contemplates the effect of texturing on a single filament (100), it should also be recognized that the false-twist process will generally be used on a yarn (300) made up of multiple filaments (100) (whether continuous filaments or chopped-up filaments in the form of staple). Without being bound to a particular theory of operation, applying the false-twist process to a multithread yarn (300) will serve to provide each filament (100) in the yarn (300) with a slight memory of the twist. The filaments (100) will then seek to push apart from each other after the process. This act of texturing will effectively create small air spaces between the filaments (100). As each filament (100) has silver particles in the sheath (103) surrounding it, by separating the filaments (100) (even by a very small amount) the yarn (300) will have an improved ability to absorb fluid and there will be a dramatically increased available silver surface area due to the increased surface area of each of the filaments (100) in the yarn (300).
It should be recognized that utilizing the false twist texturing process on a single component filament (100) and associated filament bundle (300) comprised of single component filaments (100) is also expected to increase the amount of silver accessible from the exterior of each filament (100), however, the effect will be significantly less. To use a simple comparison, in the multicomponent yarn (300), 100% of the silver in the sheath (103) would effectively be in surface contact before any material in the core would be in surface contact. Thus, in a multicomponent filament (100), the amount of silver present on the surface compared to the amount of silver used in the filament (100) construction is dramatically improved.
While the above contemplates that the purpose of the texturing is to increase silver contact, it should be recognized that if silver glass is used as the form of silver (301), the glass component can also provide for valuable characteristics, and the amount of glass available at the exterior surface will also be increased.
While the invention has been disclosed in conjunction with a description of certain embodiments, including those that are currently believed to be the preferred 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.

Claims

1. A multi-component filament comprising:

a core; and

a sheath, said sheath surrounding said core and including antimicrobial particles therein;

wherein said filament has been texturized by a false-twist process, said false-twist process increasing the amount of antimicrobial accessible at an exterior surface of said sheath.

2. The filament of claim 1 wherein said core comprises Nylon.

3. The filament of claim 1 wherein said sheath comprises Nylon.

4. The filament of claim 1 wherein said core comprises polyester.

5. The filament of claim 1 wherein said sheath comprises polyester.

6. The filament of claim 1 wherein said antimicrobial particles comprise silver metal.

7. The filament of claim 1 wherein said antimicrobial particles comprise silver glass.

8. The filament of claim 7 wherein said silver glass comprises glass particles coated with silver.

9. The filament of claim 7 wherein said silver glass comprises glass particles including silver nitrate.

10. A filament bundle comprising a plurality of filaments of claim 1

11. A filament bundle comprising:

a plurality of filaments, each of said filaments comprising:

a core; and

wherein said filament bundle has been texturized by a false-twist process to increase the amount of antimicrobial accessible by a fluid in exterior surface contact with said filament bundle.

12. The filament bundle of claim 11 wherein said core comprises nylon.

13. The filament bundle of claim 11 wherein said sheath comprises nylon.

14. The filament bundle of claim 11 wherein said core comprises polyester.

15. The filament bundle of claim 11 wherein said sheath comprises polyester.

16. The filament bundle of claim 11 wherein said antimicrobial particles comprise silver metal.

17. The filament bundle of claim 11 wherein said antimicrobial particles comprise silver glass.

18. The filament bundle of claim 17 wherein said silver glass comprises glass particles coated with silver.

19. The filament bundle of claim 17 wherein said silver glass comprises glass particles including silver nitrate.

20. A method of metalizing a synthetic filament bundle, the method comprising:

providing a plurality of synthetic filaments, each of said filaments comprising:

a core; and

a sheath, said sheath surrounding said core and including silver particles therein;

texturized said filament bundle by a false-twist process to increase the amount of silver accessible by a fluid in exterior surface contact with said filament bundle.