WO2008029387A1

WO2008029387A1 - Multi-layered material

Info

Publication number: WO2008029387A1
Application number: PCT/IL2007/001051
Authority: WO
Inventors: Jeffrey Gabbay
Original assignee: The Cupron Corporation
Priority date: 2006-09-10
Filing date: 2007-08-23
Publication date: 2008-03-13
Also published as: IL177979A0; IL177979A

Abstract

The present invention provides a multi-layered material, having anti-microbial, anti-viral and anti-fungal properties upon contact with a fluid, the material comprising at least one hydrophobic layer and at least one hydrophilic layer, and the material incorporating therein water insoluble copper oxide, the copper oxide releasing Cu++ and optionally Cu+ ions in cationic form in biocidal effective amounts when in contact with a fluid.

Description

MULTI-LAYERED MATERIAL

The present application relates to a multi-layered material having antimicrobial, anti-viral and anti-fungal properties upon contact with a fluid.

More particularly the present application relates to a multi-layered material incorporating therein water insoluble copper oxide, said copper oxide releasing Cu⁺⁺ and/or Cu+ ions in cationic form in biocidal effective amounts when in contact with a fluid.

In most hospital settings, especially where hospital staff who come in contact with body liquids that are possibly infected with viral, bacterial, and fungal pathogens, a hydrophobic quality of a garment or protective apron is the desired standard. The hydrophobic aspect of the garment or apron gives a barrier quality to the garment and thus prevents and/or barriers the pathogens from coming in contact with the person wearing the garment. While the logic of this is obvious, it creates serious environmental problems as infected blood or body liquids are not absorbed by the garment and therefore will either pour off the garment on to the shoes of the doctors or the floor or be absorbed or rubbed off on to other surfaces with possibly live pathogens in that liquid. In addition, a certain amount of the infected liquids remain on the garment (in folds or small cavities) where they retain their pathogenic nature. The pathogens can remain alive for extended periods of time, especially if these garments are not incinerated in a timely manner.

A primary demand of all medical personnel is the protection against exposure to infectious body liquids which is why all non-woven disposable garments today as well as non-disposable surgical barrier garments are made of highly hydrophobic materials. These fabrics act as barriers to protect the user in the event that pathogenic liquids splatter on or are deposited on the barrier surface.

Obviously the easiest way to make a hydrophobic barrier would be to use a hydrophobic base material such as polypropylene, polyethylene, polyolefin as examples. Further, there are a number of ways of introducing a hydrophobic quality to naturally hydrophilic materials such as cotton fabrics. In the case of a hydrophilic substrate or textile from woven or non-woven construction a coating can be added to the surface to impart the hydrophobic quality such as a fluro-carbon coating. Or, alternatively, a hydrophobic material in the form of a film can be laminated to the hydrophilic substrate thereby creating a barrier in back of the hydrophilic layer. In the case of the most commonly used non-woven materials, the material itself is made from polypropylene or some other material which is highly hydrophobic. In the case of woven medical barrier garments, most are made from either a polyester or nylon textile which are hydrophobic and as an added measure of safety are treated with a fluorocarbon or silicone compound to insure no penetration of liquids by even viral pathogens.

The proposed product discussed here is a woven, knit, spun bond, heat melt or other non-woven material which could also be a paper product or an extruded film that has both anti-microbial/anti-viral qualities, as well as hydrophobic/hydrophilic qualities or combination of any of the above.

More specifically, the present invention provides a multi-layered material, having anti-microbial, anti-viral and anti-fungal properties upon contact with a fluid, said material comprising at least one hydrophobic layer and at least one hydrophilic layer, and said material incorporating therein water insoluble copper oxide, said copper oxide releasing Cu⁺⁺ and optionally Cu⁺ ions in cationic form in biocidal effective amounts when in contact with a fluid.

In a first family of preferred embodiments of the present invention, said copper oxide is incorporated in said at least one hydrophilic layer.

In a further family of preferred embodiments of the present invention, said copper oxide is incorporated in said at least one hydrophobic layer.

In a third family of preferred embodiments of the present invention, said copper oxide is incorporated in at least one hydrophilic layer and in at least one hydrophobic layer of said material.

In preferred embodiments of the present invention, said hydrophilic layer is formed of a polymeric material.

In said preferred embodiments, preferably water-insoluble particles that release both Cu⁺⁺ and Cu⁺ are directly and completely encapsulated within said hydrophilic polymeric material.

In said preferred embodiments, alternatively, said hydrophilic layer comprises a mixture of water-insoluble particles that release both Cu⁺⁺ and Cu⁺, which particles are directly and completely encapsulated within said hydrophilic polymeric material and are the primary active component therein. In said alternative preferred embodiment, incorporating a hydrophilic polymeric layer for inactivation of a virus, said particles are preferably of a size of between about 1 and 10 microns.

In said alternative preferred embodiment, incorporating a hydrophilic polymeric layer for inactivation of a virus, said particles are present within said hydrophilic material in a concentration of about 1 to 10 w/w%.

In said preferred embodiments, preferably said hydrophilic polymeric material is selected from the group consisting of polyvinyl alcohol and cellulose based fibers.

In other preferred embodiments of the present invention, said hydrophobic layer is formed of a polymeric material.

In preferred embodiments of the present invention, said at least one hydrophilic layer is in the form of a film.

In preferred embodiments of the present invention, said at least one hydrophobic layer is in the form of a film.

In said first family of preferred embodiments, wherein, said hydrophilic layer is formed of a polymeric material, preferably said polymer is selected from the group consisting of a polyamide, a polyester, acrylic, polypropylene, silastic rubber and latex.

In said preferred embodiments, preferably said copper oxide is in the form of microscopic water insoluble particles incorporated in the polymer.

In said first family of preferred embodiments, alternatively, said at least one hydrophiiic layer is a paper-based product, formed from paper mulch, said paper product incorporating fibers coated with a Cu⁺⁺ cationic water-insoluble form of copper, wherein said paper product is effective for the inactivation of viruses and bacteria in fluids brought in contact therewith.

Preferably in said embodiment, said coated fibers are disposed in said products as randomly scattered fibers in a paper layer.

In yet another preferred embodiment of the present invention, at least one of said layers is formed from fibers having Cu⁺⁺ and optionally Cu⁺ cationic ions directly bound thereto to form a water insoluble copper oxide molecule on the surface thereof.

In a first variation of said yet another preferred embodiment, said layer is formed of non-woven fibers. In a second variation of said yet another preferred embodiment said layer is formed into a knit material.

In a third variation of said yet another preferred embodiment said layer is formed into a woven fabric.

In another aspect of the present invention, there is provided a method for producing a multi-layered material, having anti-microbial, anti-viral and anti-fungal properties upon contact with a fluid, wherein said material comprises at least one hydrophobic layer and at least one hydrophilic layer, and said material incorporates therein water insoluble copper oxide, said copper oxide releasing Cu⁺⁺ and optionally Cu⁺ ions in cationic form in biocidal effective amounts when in contact with a fluid, said method comprising forming a hydrophilic material having said copper oxide incorporated therein and then coating one surface of said material to impart a hydrophobic quality thereto.

In a first preferred embodiment of said method, said hydrophilic material is provided on one surface with a fluoro-carbon coating.

In a second preferred embodiment of said method said hydrophilic material is provided on one surface with a hydrophobic polymeric coating.

Preferably in said second preferred embodiment of said method said hydrophobic polymeric coating is formed of a polymer selected from the group consisting of polyethylene, polypropylene and polyolefin.

The present invention also provides, a further method for producing a multi- layered material, having anti-microbial, anti-viral and anti-fungal properties upon contact with a fluid, wherein said material comprises at least one hydrophobic layer and at least one hydrophilic layer, and said material incorporates therein water insoluble copper oxide, said copper oxide releasing Cu⁺⁺ and optionally Cu⁺ ions in cationic form in biocidal effective amounts when in contact with a fluid, said method comprising forming a hydrophobic material having said copper oxide incorporated therein and then treating a surface of said material to impart a hydrophilic quality thereto.

In said further preferred method, preferably, a surface of said hydrophobic polymer is treated with a hydrophilic organic hydrocarbon monomer to render said surface hydrophilic. Preferably, said hydrophilic organic hydrocarbon monomer is Triton X-100® or any compounds that yield the same surface quality to hydrophobic materials.

The present invention also provides a method for producing a multi-layered material, having anti-microbial, anti-viral and anti-fungal properties upon contact with a fluid, wherein said material comprises at least one hydrophobic layer and at least one hydrophilic layer, and said material incorporates therein water insoluble copper oxide, said copper oxide releasing Cu⁺⁺ and optionally Cu⁺ ions in cationic form in biocidal effective amounts when in contact with a fluid, said method comprising forming a hydrophilic material having said copper oxide incorporated therein, forming a hydrophobic material and laminating said materials to each other.

The present invention also provides a multi-layered material having at least one porous hydrophobic outer layer and at least one hydrophilic inner layer wherein said inner layer has incorporated therein water-insoluble copper oxide, said copper oxide releasing Cu⁺⁺ and optionally Cu⁺ ions in cationic form in biocidal effective amounts when in contact with a fluid.

A preferred embodiment of this aspect of the present invention is a multi- layered gauze pad wherein the inner gauze layers are hydrophilic and contain said copper oxide while the outer layer, because of its hydrophobic nature, does not stick to an open wound and therefore does not cause the reopening of a healing wound upon the removal thereof.

Thus, in WO 2006/048879 there appears an example wherein a patient's foot is wrapped with a gauze containing 3% cellulose fibers as prepared according to the method described in US application 10/339886, corresponding to PCT/IL03/00230, wherein said treated cellulose fibers are coated with ionic copper selected from the group consisting of Cu⁺ and Cu⁺⁺ ions in that formed on the surface of said fibers are insoluble copper oxide compounds of Cu⁺ and Cu⁺⁺

According to the present invention, such a hydrophilic gauze pad would be provided with an outer wrapping of porous hydrophobic material to enhance its healing properties in that transport of liquid and of the healing copper ions is possible between the fibers of said hydrophobic material while said hydrophobic material does not itself stick to the exudates of a healing wound.

As indicated above, at least one of the layers of the multi-layered material is preferably formed of fibers having Cu⁺⁺ and optionally Cu⁺ cationic ions directly bound thereto to form a water insoluble copper oxide molecule on the surface thereof, wherein said layer is preferably formed of non-woven fibers forming a non- woven material, a knit material or a woven fabric.

In the case of a non-woven material, the finished material will be made of more than one layer. In principal the top layer will be one that has a hydrophilic quality and the bottom one has a hydrophobic quality or visa versa which is usually not a problem because most of these materials do not have a top or bottom side.

In the case of a non-disposable material such as a textile or a film, the finished material would also be more than one layer. Again, the top layer could be absorbent cotton or other fiber and the bottom layer could be a hydrophobic coating or laminated layer. Alternatively, conventional manufacturing processes allow for a topical chemical finish on one of the layers to obtain the same effect.

With this in mind, the addition of an anti-microbial quality to these same materials as discussed above will be described hereinafter. For the purpose of the present specification, the term biocidal and the term anti-microbial is intended to refer to a material that incorporates water insoluble copper oxide which releases Cu⁺⁺ and optionally Cu⁺ ions in cationic form in biocidal effective amounts when in contact with a fluid which kill bacteria, fungi, viruses, and mites.

The anti-microbial agent being used is a copper oxide compound which can be composed of either a cuprous oxide, a cupric oxide or a combination thereof, however, most preferred is an anti-microbial agent primarily composed of cupric oxide.

The use of metals as an anti-microbial agent has a historic background. However, with regard to today's science it is not a clear scientific issue. Specifically, in the case of silver which is very commonly used today, the silver must be elemental in form. However, once the silver has oxidized it loses its efficacy. This fact is probably the reason that copper oxides haven't been used as popular antimicrobials even through they are more effective than silver. Copper as elemental copper is a very poor anti-microbial agent and so the use of a copper oxide, if we were to follow the example of silver, would not obvious. In addition, copper compounds such as copper sulfate or copper peptide compounds only demonstrate limited efficacy. This is probably due to the fact that the additional attached molecules inhibit, rather than assist, in the releasing of the correct copper oxide. In addition, the use of metals can be difficult to use as anti-microbials because, unlike organic compounds such as tetracycline or benzyl benzoate, metal and metal oxides do not leach well and therefore need additional factors not obvious to those familiar with the art of anti-microbial textiles to make them fully functional.

It is well know, that hydrophobic polymeric materials having added antimicrobial materials in the form of a metal or metal oxide placed in them simply do not function well. For this reason, when an anti-microbial technology does show up in these products, it is almost always a topical organic compound that will leach off the fabric when exposed to water. However, if water touches a polypropylene substrate with a metal oxide included in it, it will not function.

Thus, for example in JP03/11301 1 , there is described a preparation of a hydrophobic polymeric fiber having germanium and copper incorporated therein. However, said publication states that "the copper compound and the germanium compound that have been dispersion blended are disposed in the inside of the polymer tissue having a dense structure, the dispersion medium used in combination slightly spreads the space between these compounds and the polymer chain thereby permitting a slight invasion of water, and the invaded water allows the dissolution and the oozing of the compound so that the anti-microbial effect and the health effect are exhibited".

The fact that the copper and germanium are disposed on the inside of the polymer of said Japanese publication and not on the surface, and that the mechanism for release is through holes and cracks formed in the polymer for water to enter into the center of the fibers, is expected from the teaching of said publication, since it is known that germanium is inert in a polymer and creates holes therein, and it is also known that in extrusion, heavier particles gravitate towards the center of the fiber and thus the copper and germanium particles having a higher specific gravity than the polymeric material, naturally go towards the center and are not found on the surface of the fibers of the Japanese publication

The failure of such hydrophobic polymers having bioactive materials introduced therein to function is caused by the fact that the hydrophobic quality keeps liquids from coming in contact and touching the bioactive component within the polymer. This touching is required to activate a releasing of copper ions. The copper ions will remain in the copper oxide compound as long as no mechanism allows their dispersal which will happen when the dried powder is exposed to water If there is no contact with a liquid there will be no ionic dispersion. This can be demonstrated by observing the surface tension and angle of contact which would be more than 90 degrees as observed by water beading on the material surface. This is due to the extreme hydrophobic nature of the polypropylene.

A solution to this problem is presented in European patent 1272037 and in corresponding US application 10/240993 in which there are described and claimed and anti-microbial and antiviral polymeric material comprising a polymer and having microscopic water insoluble particles of copper oxide incorporated in the polymer, wherein the particles release Cu⁺⁺ and wherein a portion of said particles and exposed and protruding from the surface of said material.

As indicated above, the present invention, in one of its embodiments, provides a different solution, in that a hydrophobic polymeric substrate is converted into a multi-layered sheet of material by treating a surface thereof to convert the same into a hydrophilic layer.

This can be done either by adding a surfactant to the layer or by adding a moisture control compound to the polymer when being extruded. An example of a hydrophilic additive which can achieve this result, is a compound selected from the group of hydrophilic organic hydrocarbon monomers such as Triton X-100. It is also at this time that the copper oxide is added to the polymer. These elements are added in a concentrated form which is called a master batch.

The purpose of providing a first hydrophilic layer of anti-microbial material would be to allow the fabric to absorb the liquid containing pathogens. The active ingredient in the hydrophilic layer, the copper oxide powder, is allowed to wet and then releases its active material which destroys the pathogens. The second hydrophobic layer of the fabric may or may not have the anti-microbial component added to it but it's primary purpose is to be hydrophobic which adds the barrier quality to the fabric.

Unlike normal non-wovens, the first layer will no longer repel the liquids but absorb them thereby allowing for the destruction of the pathogens. The second layer would still afford the continued barrier protection the medical personnel desire.

What has been surprisingly found and proposed according to the present invention is the possibility of adding a hydrophilic quality to a hydrophobic material in order to allow the copper oxides to function. The copper oxides, i.e., cuprous oxide, copper oxide and combinations thereof, are normally, during extrusion, embedded in the interior of the polymer, for the reasons explained above, and if the polymer has a hydrophobic nature, that hydrophobicity will not allow the liquids to interact with the copper inside the material. As such, and as demonstrated in the examples provided herein, it is possible to see that there is substantially no effect by copper ions embedded within a hydrophobic polymer on the microbes (there is an effect but only after an extended time due to electro magnetic leaching of foreign particles in the water). However, when a hydrophilic material is added to the surface of the polypropylene or added as part of the master match to reduce the hydrophobic quality of the substrate, one can see a complete change in the biological qualities.

Thus, the present invention provides for a multi-layered material which can have two or more layers of different properties wherein at least one layer will by hydrophobic and a second layer will be hydrophilic.

In products such as pads, the top and bottom layer will be hydrophobic while the center layer is hydrophilic.

Thus the present invention provides two-layer products wherein one layer will be hydrophobic and can be spun bond or a film and one layer will be hydrophilic which layer can be a surfactant or a spun bond or can be formed from a wide variety of hydrophilic materials which includes knit and woven textiles, and non-woven materials such as needle punch materials, felt and paper-type products.

The present invention also provides in its preferred embodiments, three-layer products, wherein the top and bottom layer are hydrophobic and can be spun bond or a film, while the center layer, which is a sandwich layer, can be made of any gauze, felt or a needle punch type material which is highly absorbent. This center layer can be made from cotton or any synthetic cellulose material such as rayon and will have the water insoluble copper oxide which releases Cu⁺⁺ and optionally Cu⁺ ions in cationic form in biocidal effective amounts when in contact with a fluid incorporated therein.

Before describing the invention in more detail and with reference to examples of preparation and use, a brief review of the relevant prior art would be appropriate.

In both WO 98/06508 and WO 98/06509 there are taught various aspects of a textile with a full or partial metal or metal oxide plating directly and securely bonded to the fibers thereof, wherein metal and metal oxides, including copper, are bonded to said fibers.

More specifically, in WO 98/06509 there is provided a process comprising the steps of: (a) providing a metallized textile, the metallized textile comprising: (i) a textile including fibers selected from the group consisting of natural fibers, synthetic cellulosic fibers, regenerated fibers, acrylic fibers, polyolefin fibers, polyurethane fibers, vinyl fibers, and blends thereof, and (ii) a plating including materials selected from the group consisting of metals and metal oxides, the metallized textile characterized in that the plating is bonded directly to the fibers; and (b) incorporating the metallized textile in an article of manufacture.

In the context of said invention the term "textile" includes fibers, whether natural (for example, cotton, silk, wool, and linen) or synthetic yarns spun from those fibers, and woven, knit, and non-woven fabrics made of those yams. The scope of said invention includes all natural fibers; and all synthetic fibers used in textile applications, including but not limited to synthetic cellulosic fibers (i.e., regenerated cellulose fibers such as rayon, and cellulose derivative fibers such as acetate fibers), regenerated protein fibers, acrylic fibers, polyolefin fibers, polyurethane fibers, and vinyl fibers, but excluding nylon and polyester fibers, and blends thereof.

Said invention comprised application to the products of an adaptation of technology used in the electrolyses plating of plastics, particularly printed circuit boards made of plastic, with metals. See, for example, Encyclopedia of Polymer Science and Engineering (Jacqueline I. Kroschwitz, editor), Wiley and Sons, 1987, vol. IX, pp 580-598. As applied to textiles, this process included two steps. The first step was the activation of the textile by precipitating catalytic noble metal nucleation sites on the textile. This was done by first soaking the textile in a solution of a low- oxidation-state reductant cation, and then soaking the textile in a solution of noble metal cations, preferably a solution of Pd++ cations, most preferably an acidic PdCI₂ solution. The low-oxidation-state cation reduces the noble metal cations to the noble metals themselves, while being oxidized to a higher oxidation state. Preferably, the reductant cation is one that is soluble in both the initial low oxidation state and the final high oxidation state, for example Sn++, which is oxidized to Sn++++, or Ti+++, which is oxidized to Ti++++. The second step was the reduction, in close proximity to the activated textile, of a metal cation whose reduction was catalyzed by a noble metal. The reducing agents used to reduce the cations typically were molecular species, for example, formaldehyde in the case of Cu++. Because the reducing agents were oxidized, the metal cations are termed "oxidant cations" herein. The metallized textiles thus produced were characterized in that their metal plating was bonded directly to the textile fibers.

In WO 98/06508 there is described and claimed a composition of matter comprising:

(a) a textile including fibers selected from the group consisting of natural fibers, synthetic cellulosic fibers, regenerated protein fibers, acrylic fibers, polyolefin fibers, polyurethane fibers, vinyl fibers, and blends thereof; and

(b) a plating including materials selected from the group consisting of metals and metal oxides; the composition of matter characterized in that said plating is bonded directly to said fibers.

Said publication also claims a composition of matter comprising:

(b) a plurality of nucleation sites, each of said nucleation sites including at least one noble metal; the composition of matter characterized by catalyzing the reduction of at least one metallic cationic species to a reduced metal, thereby plating said fibers with said reduced metal.

In addition, said publication teaches and claims processes for producing said products.

A preferred process for preparing a metallized textile according to said publication comprises the steps of: a) selecting a textile, in a form selected from the group consisting of yarn and fabric, said textile including fibers selected from the group consisting of natural fibers, synthetic cellulosic fibers, regenerated protein fibers, acrylic fibers, polyolefin fibers, polyurethane fibers, vinyl fibers, and blends thereof; b) soaking said textile in a solution containing at least one reductant cationic species having at least two positive oxidation states, said at least one cationic species being in a lower of said at least two positive oxidation states; c) soaking said textile in a solution containing at least one noble metal cationic species, thereby producing an activated textile; and d) reducing at least one oxidant cationic species in a medium in contact with said activated textile, thereby producing a metallized textile.

Said publications, however, are limited to coated fibers and textiles prepared according to said processes and do not teach or suggest the possibility of incorporating copper oxide into a polymeric slurry and forming a multi-layered sheet of material comprising at least one hydrophobic layer and at least one hydrophilic layer having anti-microbial and antiviral polymeric properties, as described and exemplified herein.

In WO 94/15463 there are described anti-microbial compositions comprising an inorganic particle with a first coating providing anti-microbial properties and a second coating providing a protective function wherein said first coating can be silver or copper or compounds of silver, copper and zinc and preferred are compounds containing silver and copper (II) oxide. Said patent, however, is based on the complicated and expensive process involving the coating of the metallic compositions with a secondary protective coating selected from silica, silicates, borosilicates, aluminosilicates, alumina, aluminum phosphate, or mixtures thereof and in fact all the claims are directed to compositions having successive coatings including silica, hydrous alumina and dioctyl azelate.

In contradistinction, the present invention is directed to a multi-layered sheet of material, having anti-microbial, anti-viral and anti-fungal properties upon contact with a fluid, said sheet comprising at least one hydrophobic layer and at least one hydrophilic layer, and said sheet of material incorporating therein water insoluble copper oxide, said copper oxide releasing Cu⁺⁺ ions in cationic form in biocidal effective amounts when in contact with a fluid and methods for the preparation thereof.

In EP 427858 there is described an antibacterial composition characterized in that inorganic fine particles are coated with an antibacterial metal and/or antibacterial metal compound and said patent does not teach or suggest the possibility of incorporating copper oxide into a polymeric slurry and forming a multi- layered sheet of material comprising at least one hydrophobic layer and at least one hydrophilic layer having anti-microbial and antiviral polymeric properties, as described and exemplified herein.

In DE 4403016 there is described a bacteriacidal and fungicidal composition utilizing copper as opposed to ionic Cu⁺⁺ and said patent also does not teach or suggest the possibility of incorporating copper oxide into a polymeric slurry and forming a multi-layered sheet of material comprising at least one hydrophobic layer and at least one hydrophilic layer having anti-microbial and antiviral polymeric properties, as described and exemplified herein.

In JP-01 046465 there is described a condom releasing sterilizing ions utilizing metals selected from copper, silver, mercury and their alloys which metals have a sterilizing and sperm killing effect, wherein the metal is preferably finely powdered copper. While copper salts such as copper chloride, copper sulfate and copper nitrate are also mentioned, as is known, these are water soluble salts which will dissolve and break down the polymer in which they are introduced. Similarly, while cuprous oxide is specifically mentioned, this is a Cu⁺ ionic form, and therefore said patent does not teach or suggest the possibility of incorporating copper oxide into a polymeric slurry and forming a multi-layered sheet of material comprising at least one hydrophobic layer and at least one hydrophilic layer having anti-microbial and antiviral polymeric properties, as described and exemplified herein.

In JP-01 246204 there is described an anti-microbial molded article in which a mixture of a powdery copper compound and organic polysiloxane are dispersed into a thermoplastic molded article for the preparation of cloth, socks, etc. Said patent specifically states and teaches that metal ions cannot be introduced by themselves into a polymer molecule and requires the inclusion of organopolysiloxane which is also intended to provide a connecting path for the release of copper ions to the fiber surface. Thus, as will be realized said copper compound will be encapsulated and said patent does not teach or suggest the possibility of incorporating copper oxide into a polymeric slurry and forming a multi-layered sheet of material comprising at least one hydrophobic layer and at least one hydrophilic layer having anti-microbial and antiviral polymeric properties, as described and exemplified herein. In JP-03 113011 there is described a fiber having good antifungus and hygienic action preferably for producing underwear wherein said synthetic fiber contains copper or a copper compound in combination with germanium or a compound thereof, however, said patent teaches and requires the presence of a major portion of germanium and the copper compounds disclose therein are preferably metallic copper, cuprous iodide which is a monovalent Cu⁺ compound and water soluble copper salts. Furthermore, as described above, said patent clearly states that "the copper compound and the germanium compound are disposed on the inside of the polymer tissue" and that in fact the dispersion medium used and the germanium compound spreads the space between the compound and the polymer chain thereby rendering the entire polymer hydrophilic despite its initial hydrophobic nature. Therefore, just as the water can dissolve and ooze through the now permeable polymer, so can pathogens, since this polymer no longer acts as a water insoluble barrier. Thus, said patent does not teach or suggest the possibility of incorporating copper oxide into a polymeric slurry and forming a multi-layered sheet of material comprising at least one hydrophobic layer and at least one hydrophilic layer having anti-microbial and antiviral polymeric properties, as described and exemplified herein.

In EP 116865 there is described and claimed a polymer article containing zeolite particles at least part of which retain at least one metal ion having a bacterial property and thus said patent does not teach or suggest the possibility of incorporating copper oxide into a polymeric slurry and forming a multi-layered sheet of material comprising at least one hydrophobic layer and at least one hydrophilic layer having anti-microbial and antiviral polymeric properties, as described and exemplified herein.

In EP 253653 there is described and claimed a polymer containing amorphous aluminosilicate particles comprising an organic polymer and amorphous aluminosilicate solid particles or amorphous aluminosilicate solid particles treated with a coating agent, at least some of said amorphous aluminosilicate solid particles holding metal ions having a bactericidal actions. Thus, said patent does not teach or suggest the possibility of incorporating copper oxide into a polymeric slurry and forming a multi-layered sheet of material comprising at least one hydrophobic layer and at least one hydrophilic layer having anti-microbial and antiviral polymeric properties, as described and exemplified herein.

While the invention will now be described in connection with certain preferred embodiments in the following examples so that aspects thereof may be more fully understood and appreciated, it is not intended to limit the invention to these particular embodiments. On the contrary, it is intended to cover all alternatives, modifications and equivalents as may be included within the scope of the invention as defined by the appended claims. Thus, the following examples which include preferred embodiments will serve to illustrate the practice of this invention, it being understood that the particulars shown are by way of example and for purposes of illustrative discussion of preferred embodiments of the present invention only and are presented in the cause of providing what is believed to be the most useful and readily understood description of formulation procedures as well as of the principles and conceptual aspects of the invention. EXAMPLE 1 Step A

A master batch is prepared in concentrations ranging from 25% to 40% active anti-microbial ingredient and around 1% to 3% wetting agent. Ultimately, this master batch will be diluted down to between Vz⁰Zo to 3% in most finished polymeric products. Pigments can be added to the master batch to change color of the product as desired.

The concentrated master batch is added to a hot vat of the desired polymer which is in slurry form. The slurry is usually heated to around 250C and is in a liquid state. The master batch is mixed into the polymer. At that point, the master batch is blended homogenously into the polymer and is then transferred to a spinneret. A spinneret is usually a large tub with fine holes on the bottom of it through which the liquid polymer with the mixed master batch are passed forming the strands of the fibers. These strands solidify when exposed to air forming the fiber.

The fibers are then run between a series of barrels that compress the fiber and give it its sheath form. The thickness of the produced sheath is usually a function of the speed with which the machine is run and in normal production weights of between 10 grams per square meter and 50 grams per square meter are not considered unusual. The resultant fibers will contain both the copper oxide master batch and the hydrophilic additive in the final product. Step B - A multi-layer product

At the same time, a second layer is prepared in a subsequent machine which is usually attached to the same frame as the first machine which also extrudes a spun bond layer or heat melt layer or any other desired layer as is known in SMS systems. In the case of the second layer, no hydrophilic additive is added to the slurry. The copper oxide addition in the second layer is optional because of the hydrophobic nature of the material. It may be included to serve as a physiological advantage even though the test results attached show a reduced efficacy due to the hydrophobic nature of the materials that inhibit the transfer of ions by inhibition of a water bridge. The two layers are produced in a similar fashion and pressed together since they are still hot enough to bond to one another forming a single layer non- woven fabric. EXAMPLE 2

Using the procedure of Example 1 , but as a variation thereof, a 2 layer fabric is produced using different types of non-wovens (i.e. a spun bond layer and a heat melt layer which are well known in the industry). EXAMPLE 3

Following the procedure of Example 1 , but as a further variation thereof, a 3 layered fabric is produced using 3 different types of non-wovens. The polymer of choice can be almost any polymer but the most commonly used are polypropylene, polyethylene and polyolefm. EXAMPLE 4 A Non-Disposable Product

A staple fiber is made by adding copper oxide master batch as described above with a hydrophilic addition to an extruder producing these fibers or a cellulose staple is treated by an electroless plating system to obtain a copper oxide plating. While, in the case of the staple product the hydrophilic agent can be added to the master batch, it is also possible to add it as a general textile treatment which can also be done in example #1 but is usually less economic. The prepared copper oxide treated staple fibers are then mixed with cotton or any other absorbing fibers and converted into yarns and then either woven, needle punched to form a non- woven layer, or knit into a fabric. At the end of this process, an absorbing textile with anti-microbial qualities is obtained.

The anti-microbial textile is then either coated with a hydrophobic compound or laminated with a film that barriers the fabric. The film can be a wide range of products that would include a spun bond, heat melt, or extruded film made from a variety of polymers such as PE, PP, etc.

In both cases, a fabric or substrate will have been created that will absorb water based liquids on one side while repelling water on the other side. As the liquids containing the pathogens are absorbed, the ionic activity of the copper oxide in the absorbent layer will destroy the pathogens in the liquids while the hydrophobic layer will act as a barrier to protect the wearer.

This same process can be applied not just to textiles but to any multilayer substrate made from any non-woven, woven, knit, or extruded film. Example 5 Conversion of a Hydrophobic Material to one having a Hvdrophilic Ion Releasing Surface

A polymer is selected from a group that is naturally hydrophobic. This includes such polymers as polypropylene, polyethylene, and polyester, etc. ( In the following table spun-bond polypropylene and polyethylene films were prepared and tested.)

A master batch that is compatible with the base hydrophobic polymer is prepared that includes in its contents a copper oxide powder. Normally this master batch would also include dispersement agents as well as compounds to prevent agglomeration of the copper oxide powder so as to obtain an evenly dispersed suspension of the heavy copper oxide powder in the polymer after the master batch is melted and added to the polymeric slurry.

While in a mixed slurry, the polymer is extruded into the desired form of a sheath, film or other form and as stated in the following table, spun bound polypropylene and polyethylene film were prepared and tested.

To both the spun bound polypropylene and the polyethylene film, there were added a wetting agent or surfactant and examples of commercially available surfactants include Dynol ® from Air Products Ltd. and Faze-Wet ® by Mi Swaco

The wetting agent, or surfactant forms a weak bond with the surface of the polymer and in fact creates a hydrophilic layer which lowers the surface tension of a liquid brought into contact with the material, allowing easier spreading and lowering of the interfacial tensions between the liquid and the surface upon which it is placed and ready transport of the copper ions into said liquid to inactivate pathogens therein. As stated, there are many surfactants that are appropriate for the desired ion release and said surfactants can be organic compounds that are amphipathic, meaning they contain both hydrophobic and hydrophilic groups.

Surfactants can be included in the master batch as described in Example 4 but to avoid the issue of thermal stability they can be applied as a post extrusion treatment as described herein. The application of the surfactant to the material is preferably by means of a spray at room temperature forming a layer of the surfactant on the material which layer is dried by hot air.

The following table presents the results of laboratory testing of materials produced according to the present invention and the same material without copper oxide added thereto, said material being included as controls, with regard to their efficacy against various organisms as a function of time, of exposure and percent of reduction.

Table 1

All experiments were repeated on E. CoIi and Candida Albicans demonstrating the same exact results. All experiments were done in triplicate.

As can be seen from the above table, spun bound polypropylene and polyethylene film exhibit no biological efficacy. On the other hand a hydrophobic material such as spun-bound polypropylene or polyethylene film which has 3% copper oxide incorporated therein according to the present invention and which then is treated with a surfactant to form a hydrophilic layer enhancing the contact between a liquid and the material and the copper oxide contained therein, exhibit a 99.99% reduction in the presence of the test organisms.

Thus there is produced a material which is hydrophilic on one of its surfaces with enhanced efficacy and hydrophobic on its other surface, said hydrophobic surface serving as a barrier to the passage of pathogen containing liquids therethrough.

According to other preferred embodiments of the present invention a first untreated hydrophobic material and a second treated, copper oxide containing hydrophilic material are laminated together and as such the hydrophobic side shows no activity and the hydrophilic side shows activity.

Thus the hydrophobic side acts as a barrier whereas the hydrophilic acts to destroy the microbes.

It will be evident to those skilled in the art that the invention is not limited to the details of the foregoing illustrative examples and that the present invention may be embodied in other specific forms without departing from the essential attributes thereof, and it is therefore desired that the present embodiments and examples be considered in all respects as illustrative and not restrictive, reference being made to the appended claims, rather than to the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein.

Claims

WHAT IS CLAIMED IS:

1. A multi-layered material, having anti-microbial, anti-viral and anti-fungal properties upon contact with a fluid, said material comprising at least one hydrophobic layer and at least one hydrophilic layer, and said material incorporating therein water insoluble copper oxide, said copper oxide releasing Cu⁺⁺ and optionally Cu⁺ ions in cationic form in biocidal effective amounts when in contact with a fluid.

2. A multi-layered material according to claim 1 , wherein said copper oxide is incorporated in said at least one hydrophilic layer.

3. A multi-layered material according to claim 1 , wherein said copper oxide is incorporated in said at least one hydrophobic layer.

4. A multi-layered material according to claim 1 , wherein said copper oxide is incorporated in at least one hydrophilic layer and in at least one hydrophobic layer of said material.

5. A multi-layered material according to claim 1 wherein said hydrophilic layer is formed of a polymeric material.

6. A multi-layered material according to claim 1 wherein said hydrophobic layer is formed of a polymeric material.

7. A multi-layered material according to claim 6 wherein said polymer is selected from the group consisting of a polyamide, a polyester, acrylic, polypropylene, silastic rubber and latex.

8. A multi-layered material according to claim 6 wherein said copper oxide is in the form of microscopic water insoluble particles incorporated in the polymer.

9. A multi-layered material according to claim 1 wherein said at least one hydrophilic layer is a paper-based product, said paper product incorporating fibers coated with a Cu⁺⁺ and optionally Cu⁺ cationic water- insoluble form of copper, wherein said paper product is effective for the inactivation of viruses and bacteria in fluids brought in contact therewith.

10. A multi-layered material according to claim 9 wherein said coated fibers are disposed in said products as randomly scattered fibers in a paper layer.

11. A multi-layered material according to claim 5 wherein water-insoluble particles that release both Cu⁺⁺ and Cu⁺ are directly and completely encapsulated within said hydrophilic polymeric material.

12. A multi-layered material according to claim 5 wherein said hydrophilic layer comprises a mixture of water-insoluble particles that release both Cu⁺⁺ and Cu⁺, which particles are directly and completely encapsulated within said hydrophilic polymeric material and are the primary active component therein.

13. A multi-layered material according to claim 12 incorporating a hydrophilic polymeric layer for inactivation of a virus wherein said particles are of a size of between about 1 and 10 microns.

14. A multi-layered material according to claim 12 incorporating a hydrophilic polymeric layer for inactivation of a virus wherein said particles are present within said hydrophilic material in a concentration of about 1 to 10 w/w%.

15. A multi-layered material according to claim 12 incorporating a hydrophilic polymeric material for inactivation of a virus wherein said hydrophilic polymeric material is selected from the group consisting of polyvinyl alcohol and cellulose based fibers.

16. A multi-layered material according to claim 1 wherein at least one of said layers is formed from fibers having Cu⁺⁺ and optionally Cu⁺ cationic ions directly bound thereto to form a water insoluble copper oxide molecule on the surface thereof.

17. A multi-layered material according to claim 16 wherein said layer is formed of non-woven fibers.

18. A multi-layered material according to claim 16 wherein said layer is formed into a knit material.

19. A multi-layered material according to claim 16 wherein said layer is formed into a woven fabric.

20. A multi-layered material according to claim 1 wherein said at least one hydrophilic layer is in the form of a film.

21. A multi-layered material according to claim 1 wherein said at least one hydrophilic layer is in the form of a film.

22. A multi-layered material according to claim 1 wherein said at least one hydrophobic layer is in the form of a film.

23. A method for producing a multi-layered material, having anti-microbial, anti-viral and anti-fungal properties upon contact with a fluid, wherein said material comprises at least one hydrophobic layer and at least one hydrophilic layer, and said material incorporates therein water insoluble copper oxide, said copper oxide releasing Cu⁺⁺ and optionally Cu⁺ ions in cationic form in biocidal effective amounts when in contact with a fluid, said method comprising forming a hydrophilic material having said copper oxide incorporated therein and then coating one surface of said material to impart a hydrophobic quality thereto.

24. A method according to claims 23, wherein said hydrophilic material is provided on one surface with a fluoro-carbon coating.

25. A method according to claims 23, wherein said hydrophilic material is provided on one surface with a hydrophobic polymeric coating.

26. A method according to claim 25 wherein said hydrophobic polymeric coating is formed of a polymer selected from the group consisting of polyethylene, polypropylene and polyolefin.

27 A method for producing a multi-layered material, having anti-microbial, antiviral and anti-fungal properties upon contact with a fluid, wherein said material comprises at least one hydrophobic layer and at least one hydrophilic layer, and said material incorporates therein water insoluble copper oxide, said copper oxide releasing Cu⁺⁺ and optionally Cu⁺ ions in cationic form in biocidal effective amounts when in contact with a fluid, said method comprising forming a hydrophobic material having said copper oxide incorporated therein and then treating a surface of said material to impart a hydrophilic quality thereto.

28 A method according to claim 27 wherein a surface of said hydrophobic polymer is treated with a hydrophilic organic hydrocarbon monomer to render said surface hydrophilic.

29. A method according to claim 28 wherein said hydrophilic organic hydrocarbon monomer is Triton X-100®.

30. A method for producing a multi-layered material, having anti-microbial, antiviral and anti-fungal properties upon contact with a fluid, wherein said material comprises at least one hydrophobic layer and at least one hydrophilic layer, and said material incorporates therein water insoluble copper oxide, said copper oxide releasing Cu⁺⁺ and optionally Cu⁺ ions in cationic form in biocidal effective amounts when in contact with a fluid, said method comprising forming a hydrophilic material having said copper oxide incorporated therein, forming a hydrophobic material and laminating said materials to each other.

31. A multi-layered material having at least one porous hydrophobic outer layer and at least one hydrophilic inner layer wherein said inner layer has incorporated therein water-insoluble copper oxide, said copper oxide releasing Cu⁺⁺ and optionally Cu⁺ ions in cationic form in biocidal effective amounts when in contact with a fluid.

32. A multi-layered material according to claim 31 comprising a multi-layered gauze pad wherein the inner gauze layers are hydrophilic and contain said copper oxide and the outer layer is formed of a porous hydrophobic material.