ANTIVIRAL AND ANTIMICROBIAL FABRIC TREATMENT AS WELL AS FABRICS

TREATED THEREWITH

TECHNICAL FIELD

The present invention relates to methods for the preparation of aqueous antibacterial and antiviral formulations for textile treatment, to formulations obtained by such a method, to uses of such formulations in particular for textile treatment, to textiles obtained using such formulations as well as methods for treating textiles with such formulations.

PRIOR ART

Viruses and bacteria are, in spite of medicine and hygienic conditions having improved, still a considerable threat to mankind. In particular lethal viruses regularly emerge for whichever reason, leading to epidemic or even pandemic situations.

There is therefore an urgent need for protective measures to avoid infection. In particular in the field of medical care, but also in the field of personal protection, textiles are used, in many forms, including for example masks, face coverings, protective suits, et cetera. These textiles, to be worn and handled, are preferably at least partially air permeable, and therefore cannot fully prevent penetration of viruses or bacteria carried around by aerosols or transferred through contact with contaminated surfaces and the like. Furthermore, even if these textiles are impermeable, they need to be handled after use, which may involve touching them with unprotected hands et cetera. Considering that viruses can survive several days, this can lead to further problems even if wearing protective clothing. US9487912 discloses a disinfectant composition for textile and related substrates, and a method of treating a substrate to provide disinfecting antibacterial, antiviral and antifungal, wash durable, optionally enhanced with multifunctional properties. The active substances (e.g. quaternary ammonium silane, silver salts, PHMB) are formulated in combination with antifungal agents thiabendazoles or propiconazoles.

WO2007135163 proposes the use of poly(hexamethylene biguanide)hydrochloride as an antiviral agent for treating textiles.

CN1285432 discloses an anti-virus, anti-bacteria finishing agent. Fabric treatment is based on alkyl-dimethyl-benzyl-ammonium chloride, octamethyl cyclotetrasiloxane polymer and sodium hydroxide.

US 9,144,237 discloses sterilizing and deodorizing agents targeting bacteria, odors, toxic substances, etc., which are made from silver as metal particles and titanium dioxide as ceramic particles by (1) thermal bonding or (2) pressure bonding or (3) thermal/pressure bonding and mixing the resultant with hydroxyapatite as an adsorptive material. The agent can be mixed with ink, bonding agents and paints and applied to a variety of substrates. CN-A-107823222 provides a nanoscale compound antibacterial agent and a preparation method and application thereof, which relate to the technical field of antibacterial agents. The nanoscale compound antibacterial agent is mainly prepared from nanosilver, graphene, protein, phospholipid, polysaccharide, cholesterol, vitamin and other raw materials, functional substances, such as the vitamin, are wrapped by a lipidosome formed by the protein, the phospholipid, the cholesterol and other materials, moreover, the nanosilver, the graphene and other materials are loaded inside or on the surface of the lipidosome after being compounded, and thereby the nanoscale compound antibacterial agent which is highly similar to a cellular structure is produced. The invention further provides the preparation method of the nanoscale compound antibacterial agent, and the method can realize the uniform mixing of all the materials, thus being favorable for the increase of the stability of the nanoscale compound antibacterial agent.

EP-A-2369923 relates generally to the field of antibacterials and to the treatment, inhibition and prevention of disorders caused by bacteria. More particularly, this invention concerns a method for inhibiting gram-positive bacteria with a composition comprising at least one non-phospholipid lipid vesicle.

CN-A-107604662 provides a bactericidal and antiviral composition for modifying textiles. By weight, the bactericidal and antiviral composition for modifying textiles includes 20-50 parts of a chitosan quaternary ammonium salt, 2-10 parts of a penetrant, 1-5 parts of a cationic surfactant, 3-15 parts of nano-silver loaded modified chitosan, and 30-50 parts of purified water. Specifically, the chitosan quaternary ammonium salt is chitosan grafted biquaternary ammonium salt A and biquaternary ammonium salt B, the preparation raw materials of the biquaternary ammonium salt A include: 1-beta-D-ribofuranose-1 , 2, 4-triazole-3- hydroxyamide, epichlorohydrin and long chain alkyl tertiary amine, and the preparation raw materials of the biquaternary ammonium salt B include: 1-hydroxyethyl-2-methyl-5- nitroimidazole, epichlorohydrin and long chain alkyl tertiary amine. And the modified chitosan is a chitosan organosilicon compound.

US-A-2012294919 relates to an antimicrobial metal composite formed by vaporizing an antimicrobial metal or antimicrobial metal salt such as silver, copper or salts thereof using an plasma system and cooling the formed vapor in the presence of a fluidized gas of filler powder. Alternatively, the filler or a filler precursor is entrained with the antimicrobial metal or antimicrobial metal precursor and vaporized and then upon cooling the antimicrobial metal vapor and filler vapor condense to form the composite. The composite shows high antimicrobial activity and can be incorporated into or onto polymers, coatings, textiles, paper, gels (for example for wound care), lubricants, adhesives and cosmetics or pharmaceutical, especially medical devices.

SUMMARY OF THE INVENTION

It is therefore the aim of the present invention to provide for highly efficient antiviral and antibacterial protection of in particular textiles. Bacteria and viruses contacting the textile impregnated with such a formulation shall be killed and/or inactivated as effectively as possible. The invention is however not limited to treating textiles, but is aiming at protecting any kind of object at the surface of which or within which an antibacterial and antiviral effect is desired. The field of application therefore extends to textiles, be it woven, nonwoven or knitted, but also to objects to be protected from viruses and bacteria, for example because these objects in their intended use are contacted by people using them, such as housings for medical devices, medical devices as such, protective glasses, foils and objects based on such foils, such as protective tools in particular for healthcare applications, such as viewing shields, protection hoods, protective suits, but also carpets, shieldings, division walls, carpets, covers, for example for lamps, beds, healthcare devices, packaging material for sensitive objects, et cetera.

The problem with known antiviral or antibacterial (textile) formulations is that they are not suitable for broadband protection, and impart protection for certain types of bacteria or certain types of viruses only. On the other hand, the chemical systems being the basis for the corresponding formulations are very different, and are incompatible to be combined in one single textile treatment formulation. It is therefore a further aim of the present invention to provide for a method for the preparation of a broadband antiviral and antibacterial textile treatment formulation.

More specifically, the invention proposes a method for the preparation of an aqueous antibacterial and antiviral formulation in particular for textile treatment, which in combination contains silver particles as well as non-phospholipid vesicles.

The proposed (textile) treatment combines two separately-produced functional formulation components:

Formulation A: Silver-based particles in aqueous suspension

Formulation B: An aqueous vesicle emulsion, preferably with cyclodextrin-based components.

Formulation A and formulation B may be blended in various proportions, and with other formulation components to form a stable Product formulation.

As concerns Formulation A, it is specifically pointed out that while being described in the following often times in combination with formulation B, the corresponding formulations A are also independently and without being mixed with formulation B considered as separate inventions. Also a separate invention is any kind of description being given in the following of methods preparing such formulations of the type A.

The combined product formulation, but also the formulation A alone, may be applied to fabric substrates (e.g. woven, knitted, and non-woven), or to any object to be protected as defined above, in order to achieve antimicrobial and antiviral functionality.

The mixture of formulation A and formulation B results in a combined aqueous formulation that involves a dispersion with silver-based particles and emulsion of non-phospholipid vesicles whereby these components are discrete dispersed components. This is in contrast to the teachings of CN-A-107823222 whereby a desired formulation is to have the antibacterial silver component intermingled with the lipidosome components in such a way that the antibacterial component is loaded inside or directly on the surface of the lipidosome structures with the teachings directing towards similarity to a cellular structure containing both components in single blended particle. This emphasis on a combined structure is further reflected in the emphasis of using a ultra-high pressure micro-jet circulation process that seeks to intimately combine the antibacterial components and the lipidosome components into highly amalgamated structures. In contrast the present invention involves blending of two separately prepared aqueous formulations that emphasizes the respective silver-based particles and non-phospholipid vesicles remaining as separate discrete structures in a combined aqueous medium. CN-A-107823222 specifically instructs that the inclusion of cholesterol in the product formulation is advantageous whereas the present invention specifically rather seeks to avoid the inclusion of cholesterol in the formulation as the non-phospholipid vesicles are designed to interact with and deplete the cholesterol layer surrounding enveloped viruses leading to antiviral effect. It is preferred not to have any cholesterol as lipid vesicle forming systems, because inclusion of cholesterol in the formulation may degrade the intended efficacy of the non-phospholipid vesicles. Application onto the various fabric substrates may variously be achieved through industrial processes (e.g. padding, dipping, coating, spraying, printing etc.).

Typical applications for fabrics or foils and objects based on foils treated with the formulation include textile or protective articles for use in sensitive environments including masks, filters, gowns, drapes, coverings, carpets etc.

More generally speaking, the proposed invention provides a method for the preparation of an aqueous antibacterial and antiviral formulation in particular for textile treatment comprising silver micro or nanoparticles, preferably silver-silica micro composite particles or silver chloride particles as well as non-phospholipid lipid vesicles (nPLV) or without such non-phospholipid lipid vesicles. The proposed method in case of the combination of both formulations is characterised in that separately

• a first aqueous formulation comprising silver nano or micro particles, preferably silver-silica micro composite particles and/or silver chloride particles, and no non phospholipid lipid vesicles (formulation A) and

• a second aqueous formulation comprising non-phospholipid lipid vesicles and no silver particles (formulation B) are prepared.

Subsequently the first and second aqueous solutions are blended, optionally with addition of water and additional additives, at a temperature of at most 40°C, for the combination formulation.

Said first aqueous formulation (formulation A) is prepared in that silver micro or nanoparticles, preferably silver-silica micro composite or silver chloride particles, are added to water, together with at least one cationic or non-ionic surfactant, optionally with addition of further silver formulation additives, until a stable homogenous dispersion is formed containing silver micro or nanoparticles, preferably silver chloride particles or silver-silica micro composite particles, in association with said cationic or non-ionic polymeric or nonpolymeric surfactant. Preferably, in case of silver-silica micro composite particles a cationic surfactant is used, and in case of silver chloride particles a non-ionic surfactant is used. Preferably, the surfactants are polymeric surfactants. When talking about silver chloride particles in this application this includes silver chloride particles as such but also composite particles, in which silver chloride is embedded or in the form of aggregates with other particles, e.g. in the form of titanium dioxide particles which are aggregated with silver chloride particles.

Said second aqueous formulation, if used, is prepared in that at least one vesicle-forming non-phospholipid and optionally further vesicle formulation additives are added to water, are mixed at elevated temperature of more than 50°C, until homogeneous mixture is obtained, and subsequently cooled to a temperature of at most 40°C under formation of homogeneous emulsion.

The preferred silver component used in the formulation is based on a silver-silica composite powder. The particles particularly useful for use in the proposed invention can be obtained using the method as disclosed in US2009131517, the disclosure of which in terms of the making process is expressly included into this disclosure. Typically, the weight proportion of silver in relation with the amorphous silica in these particles is in the range of 1 :8-1 2, preferably in the range of 1:4, and/or the silver-silica micro composite particles preferably have an average size in the range of 0.1-10 pm, preferably in the range of 0.5 - 5.0 pm, and the silver is preferably embedded in these particles in the form of particles with an average diameter in the range of 1- 10 nm. Averages are given as number averages.

Alternatively, the silver component used in the formulation is based on silver chloride, preferably in the form of a combined silver chloride titanium dioxide composite product. The proportion (by weight) of silver chloride to titanium dioxide is preferably in the range of 10:90-30:70, and the particle size of the corresponding composite powder is above 100 nm, preferably in the range of 200-1000 nm (d50).

The silver material is formulated together with additional components to facilitate formulation properties such as stability, compatibility, ease of processing, durability etc., wherein of particular importance there is a cationic or non-ionic surfactant. So also non ionic surfactants can be added, particularly preferably if silver chloride titanium dioxide composite particles are used.

In addition or as an alternative to the silver metal - silicon dioxide composite material, therefore other silver-based solids may be employed such as particulate nanosilver, silver chloride particles either suspended directly or supported as part of a titanium dioxide composite (e.g. Clariant JMAC).

The vesicle formulation component is based on a non-phospholipid vesicle structure that interacts with enveloped virus types to render removal of the lipid envelop and subsequent denaturing of the virus RNA or DNA internal genetic materials. This technology as such is known in the art and has shown to be efficient for example from US 5,561 ,062 or US 8,889,398.

The problem associated with the co-formulation of a silver particle based antibacterial/antiviral formulation with a vesicle based formulation is that adding active silver particles simply to a vesicle based formulation will negatively influence the vesicles and/or silver materials and will mutually degrade them at the moment of mixing and in particular upon storage. Preparing a stable combined formulation with silver particles and antiviral vesicles is therefore not simply possible.

What has been found now is that surprisingly it is possible to co-formulate silver particles and vesicle based antiviral formulations by separately preparing a silver micro or nano particle based dispersion and vesicle based antiviral emulsion/formulation, and to then combine them essentially at room temperature only. The silver particle dispersion to this end is prepared in that the silver particles are co-formulated with a cationic or non-ionic surfactant, which forms a micro composite with a polymeric resin matrix or non-ionic matrix in close local proximity surrounding the micro composite structure effectively enveloping the silver particles. By first preparing these micro composites the negative interaction between the vesicle components and the silver particles and also between the cationic or non-ionic surfactants on the vesicles is surprisingly reduced and stable formulations can be obtained that can be used for textile treatment and that, e.g. on the textile, have a high antiviral and antibacterial effect.

So the principle of the preparation is to surround the silver-silica microcomposite or silver chloride particle with polymeric resin matrix or a non-ionic matrix that contains a cationic /non-ionic surfactant component. The close association of the cationic/non-ionic surfactant component and the (polymeric) matrix is advantageous from a perspective of formulation stability and also efficacy of the formulated product. In case of surrounding silver chloride particles, in particular silver chloride titanium dioxide composite particles, preferably a nonionic surfactant is first surrounding the micro composite and is then stabilised for example with ethylene glycol.

The initial step of the procedure involves blending the silver-silica microcomposite or silver chloride into a solution of the matrix components e.g. followed by high intensity mixing through bead milling (typically for a time span in the range of 4 - 12 hours).

The matrix preparation procedure generates a homogeneous mixture where the matrix components penetrate into and surround the silver-silica microcomposite particles.

The balance of ingredients (surfactants and viscosity modifier components) can be formulated together prior to introduction of the matrix preparation via in-line high shear mixer.

The resulting formulation is a homogeneous dispersion with excellent storage and operational stability.

For the cationic or non-ionic surfactant component in the matrix a wide range of alternatives is given, including cosmetic cationic or non-ionic surfactants and amino-based surfactants and polymers.

The silver-based component in the example is a silver-silica composite, however alternative silver forms may be used separately or in combination (e.g. nanoparticulate silver, silver colloids, silver chloride particles, silver chloride supported on titanium dioxide, etc.). It is also possible to introduce further antimicrobial metal or metal oxide forms such as based on copper as an alternative or in combination with the silver material(s).

The use of silver silica particles is one preferred embodiment, however according to another preferred embodiment the silver in the formulation is in the form of a micro composite or nano composite particle comprising silver chloride and titanium dioxide. Preferably, such a system is generated by precipitating silver chloride on the surface of titanium dioxide particles, and the titanium dioxide particles preferably have a particle size (d50) in the range of 0.2 to 0.8 pm. In case one uses such silver chloride and titanium dioxide composite particles, using the above-mentioned cationic surfactant can still be beneficial but is not necessarily required any more. Matrix and auxiliary reagents may be substituted for various functionally similar components.

The final functionality of the product formulation requires stability of both vesicle structures and silver particles within the final product formulation.

While the vesicle structures are stable in the separately prepared vesicle formulation and the silver formulation, respectively, it is not obvious that a blended formulation of the two component formulations would achieve stability.

A stable combined formulation needs to preserve the vesicle structures and to maintain a homogeneous distribution of the silver particles throughout the mixture.

For a blended formulation involving vesicle structures, it is known art that there are many surfactants and auxiliary reagents that may disrupt the stability and structural integrity of the vesicles. Furthermore, agglomeration and flocculation of particulate dispersions such as the silver formulation can be induced through introduction of surfactants and other reagents.

A significant feature of the present invention is that it has been possible to achieve a stable formulation of the vesicle and silver particle components together in the same formulation. The formulation stability may be achieved across a range of blend ratios that cannot be predicted a priori.

A principle for achieving the blended formulation stability is the unique role of the silver formulation where the silver ingredients are embedded within a resinous matrix with close association with a cationic surfactant. This approach results in keeping cationic or non-ionic surfactants in close proximity with the silver ingredient rather than distributing homogenously in the final blended product formulation where it may be available for interacting with and potentially disrupting the vesicle structures.

A further principle for achieving stability of the combined formulation is maintaining similar pH character for each component formulation prior to blending.

The combined interaction of the silver (together with selected co-ingredients) and the non phospholipid vesicle enables an enhanced level of antiviral activity against both enveloped viruses and also non-enveloped viruses.

Silver (via silver ions and/or silver metal) provides antiviral action against both enveloped and non-enveloped viruses. It would be expected that the lipid layer of enveloped viruses provides greater resistance to diffusion of silver ions and subsequent interaction with the RNA or DNA material compared to non-enveloped viruses. In contrast, the lipid-mediating mechanism of the vesicle technology is specific to enveloped viruses.

The combined action of silver and vesicle structure therefore acts to enable greater activity of silver against enveloped viruses while also providing action against non-enveloped viruses. The selected formulation co-ingredients in principle lead to greater level of proximity of the silver materials with the virus materials, leading to enhanced antiviral action of the silver ions and/or silver-based particles. Some of the components may also have a basis for direct degrading action against viruses.

The silver materials are formulated with a range of co-ingredients including cationic surfactants (e.g. Cocobis(2-hydroxyethyl) methylammonium chloride) or non-ionic surfactants.

Cationic but also non-ionic surfactants in particular have shown potential for interaction with enveloped viruses, including in the presence of proteins. The apparent binding tendency of cationic surfactants with enveloped virions means that for silver components that are closely surrounded by the cationic surfactants, the virions may be actively brought into closer proximity to the silver source, leading in principle to greater antiviral efficacy of the silver. According to a first preferred embodiment, said cationic surfactant is a quaternary surfactant, preferably a polymeric quaternary ammonium surfactant, in particular based on fatty acid based building blocks, polyacrylate building blocks, polymethacrylate building blocks, C10-C20 alkyl building blocks, benzyl building blocks, or a combination or mixture thereof.

Said cationic surfactant is preferably selected from the group consisting of: quaternary ammonium polyacrylate, quaternary ammonium ethoxylate, quaternary ammonium propoxylate, quaternary ammonium fatty acid derivative, and is most preferably selected from the group consisting of: poly(2-(trimethylamino)ethyl methacrylate), coconut bis-(2- hydroxyethyl) methyl ammonium, oleyl bis-(2-hydroxyethyl)methyl ammonium, erucyl bis(2- hydroxyethyl)(methyl)ammonium, benzyl(2-hydroxyethyl)dimethylammonium chloride, dodecylbis(2-hydroxyethyl)methylammonium, or a combination or mixture thereof. The negatively charged counterions for the ammonium cation in these systems can e.g. be chloride or bromide or combinations thereof, but also other inorganic systems such as sulfates, phosphates are possible or organic counterions such as acetates, or polymeric organic anions.

Preferably in case of silver chloride particles, said non-ionic surfactant can be a polyethoxylated and/or polypropoxylated surfactant, in particular based on fatty acid based building blocks, C10-C40 alkyl, aryl or arylalkyl building blocks, or a combination or mixture thereof.

Preferably the non-ionic surfactant is selected from the group consisting of: alcohol C10- C28, preferably alcohol C10 - C20, most preferably alcohol C12 - C18 or alcohol C16-18, tristyrylphenol tridecyl ether, ethoxylated in each case with 3-70 EO units, preferably with 20-60 EO units, most preferably with 30-50 EO units, wherein most preferably a system of the type alcohol C16-C18+50EO is used.

The first aqueous formulation can be prepared in that the silver-silica micro composite particles are added to water together with said cationic surfactant, wherein the proportion of silver-silica micro composite particles is in the range of 0.1-1 %(w/w), preferably in the range of 0.2-0.5 %(w/w) and wherein the proportion of the cationic surfactant is in the range of 0.5-7.5% (w/w), preferably in the range of 1.5-5% (w/w) . Preferably the proportion of the cationic surfactant if chosen as an ammonium compound is given for the chloride or bromide form. The concentrations in this case are given for the final formulation A.

The first aqueous formulation can alternatively be prepared in that the in that the silver- chloride particles are added to water together with said non-ionic surfactant, wherein the proportion of silver-chloride particles is in the range of 5-15 %(w/w), preferably in the range of 7-12 %(w/w) and wherein the proportion of the non-ionic surfactant is in the range of 0.5- 12% (w/w), preferably in the range of 1-10% (w/w), and wherein the resulting mixture is mixed, preferably through milling, preferably through bead milling, for a time span of at least an hour, more preferably for a time span of more than 5 hours, at a temperature of at least 20°C, preferably at a temperature at or above room temperature. The concentrations in this case are given for the final formulation A.

According to another preferred embodiment, the silver formulation can be prepared in a two-step process, in a first step phase A is produced by suspending silver-containing particles within the cationic or non-ionic surfactant under intensive mixing, separately prepare an aqueous formulation with stabilising components such as rheology thickeners et cetera (phase B) and then introduce phase A into phase B in a manner to achieve homogeneous distribution within phase B, wherein phase B is the larger proportion of the final blend weight and forms more than 50% of the final formulation weight of formulation A. Preferably, the resulting mixture is mixed, preferably through milling, preferably through bead milling, for a time span of at least an hour, more preferably for a time span of more than 5 hours, at a temperature of at least 20°C, preferably at a temperature at or above room temperature.

Preferably as further silver formulation additives prior to mixing, or in the above process involving phase B, additives can be added selected from the group consisting of: alcohols, glycols, polyols, diols, phosphates, acids such as acetic acid, fragrance, colorants, nonionic surfactants, odorants, anti-foaming agents, foaming agents, rheology modifiers such as thickeners or a combination thereof. These additives or just some of them may also be added only after the mixing of the silver (silica) particles and the cationic or non-ionic surfactant, in particular additives such as thickeners are of this kind.

It is again to be stressed that all this description above about the composition and the method of preparing formulation A is also regarded as an independent invention independent of formulation B and the combined product involving formulation A as well as B.

The vesicle-forming non-phospholipid can be selected from the group consisting of, the values in brackets indicating the hydrocarbon chain: fatty alcohol (C12-C20), fatty acid (C12-C20), ethoxylated (C12-C20) fatty alcohol, glycol ester of (C12-C20) fatty acid, ethoxylated of (C12-C20) fatty acid, glycerol fatty acid (C12-C20) monoester, glycerol fatty acid diester (C12-C18), ethoxylated glycerol fatty acid ester (C16-C18), fatty acid diethanolamide (C12-C20), fatty acid dimethyl amide (C12-C20), fatty acid sarcosinates (C12-C20), or a combination thereof.

Preferably, the vesicle-forming non-phospholipid is selected from a polyoxyethylene cetyl ether, palmitic acid, hexadecyl trimethylammonium bromide or chloride, oleic acid or a combination thereof.

Said vesicle formulation additives may comprise enhancers for the antiviral effect, e.g. selected from the group consisting of: poly- or oligosaccharides such as xylitol, in particular cyclodextrin or derivatives thereof, or a steroidogenic acute regulatory protein.

The second aqueous formulation can be prepared in that said vesicle-forming nonphospholipid and optionally further vesicle formulation additives are added to water, are mixed at elevated temperature of more than 55°C, until homogeneous mixture is obtained, and subsequently cooled to a temperature of at most 30°C under formation of homogeneous emulsion. Typically the proportion of the at least one vesicle-forming non phospholipid is in the range of 1-8 %(w/w), preferably in the range of 2-5 %(w/w) and wherein the proportion of the enhancer if present is in the range of 1-8 % (w/w), preferably in the range of 2-6 % (w/w).

The second aqueous formulation preferably comprises, as non-phospholipid, a mixture of polyoxyethylene (2) cetyl ether with hexadecyltrimethylammonium (which can be in the chloride or bromide form, preferably in the bromide form), preferably in a weight proportion of 20: 1-5:1, most preferably 12:1-8:1, in a total concentration (taking the sum of polyoxyethylene (2) cetyl ether with hexadecyltrimethylammonium (bromium)) in the range of 3-5% (w/w).

Further preferably, the second aqueous formulation comprises, as enhancer, cyclodextrin, preferably (2-hydroxypropyl)-beta-cyclodextrin, in a proportion of 1-7% (w/w), preferably in the range of 3-6% (w/w).

The first and second aqueous solutions can be blended at a temperature of at most 40°C, preferably around room temperature, and wherein preferably 5-20% (w/w) of said first aqueous formulation are combined with 70-90% (w/w) of said second aqueous formulation, supplemented with water to a total of 100% (w/w).

The present invention further relates to an aqueous antibacterial and antiviral formulation in particular for textile treatment comprising silver-silica micro composite particles or silver chloride particles alone or in combination with, i.e. as well as non-phospholipid lipid vesicles (nPLV), preferably obtained using a method as described above.

Such a formulation comprises the silver-silica micro composite particles or silver chloride particles in association with said cationic or non-ionic polymeric surfactant, wherein preferably the silver-silica micro composite particles are present in a proportion in the range of 0.01-0.1% (w/w), preferably in a proportion in the range of 0.02-0.05% (w/w), wherein the at least one cationic polymeric surfactant is present in a proportion in the range of 0.1-0.5% (w/w), preferably in the range of 0.2-0.4% (w/w), and wherein said at least one vesicleforming non-phospholipid is present in a proportion in the range of 2-5% (w/w), preferably in the range of 2.5-4% (w/w).

In case of silver-chloride particles these are preferably present in a proportion 5-15 %(w/w), preferably in the range of 7-12 %(w/w), and wherein the at least one non-ionic polymeric surfactant is present in a proportion in the range of 0.5-12% (w/w), preferably in the range of 1-10% (w/w).

Also the present invention relates to the use of a formulation, formulation A alone or the combined product comprising formulation A as well as formulation B, as detailed above or as obtained using a method as detailed above for the treatment of objects, in particular leather, fibrous materials such as paper and cardboard articles, polymeric surfaces including polyurethane, tarps, tents, bags, luggage, or of textiles, in particular for the treatment of woven, knitted or nonwoven textiles, preferably in the field of textiles for antiviral and/or antibacterial applications including masks, filters, gowns, drapes, coverings, carpets et cetera in particular for healthcare/hospital uses.

In addition to that, the present invention relates to an object in particular an object to wear, touch or to carry by a human to be protected, in particular leather, fibrous materials such as paper and cardboard articles, polymeric surfaces including polyurethane, tarps, tents, bags, luggage, a woven or knitted or nonwoven textile treated with a formulation (formulation A alone or combined product) obtained using a method as detailed above or treated with the formulation as detailed above, preferably in the field of textiles for antiviral and/or antibacterial applications including masks, filters, gowns, drapes, coverings, carpets et cetera in particular for hospital uses.

Last but not least the present invention relates to a method for rendering an object to be protected, in particular an object based on leather, fibrous materials such as paper and cardboard articles, polymeric surfaces including polyurethane, tarps, tents, bags, luggage, woven or nonwoven textile antibacterial and/or antiviral by treating it with a formulation (again formulation A alone or the combined product in each case) obtained using a method as detailed above, or with a formulation as described above, wherein the formulation is preferably applied by padding, dipping, coating, spraying, printing or a combination thereof, and wherein the formulation is further preferably added to the textile in the range of 2-30% (weight of fabric basis), preferably in the range of 5-20%.

Further embodiments of the invention are laid down in the dependent claims.

DESCRIPTION OF PREFERRED EMBODIMENTS Preferred embodiments of the invention are described in the following with reference to the examples, which are for the purpose of illustrating the present preferred embodiments of the invention and not for the purpose of limiting the same.

Vesicle formulation:

An illustrative vesicle formulation composition is as follows:

Preparation procedure

Blending of components at elevated temperature (e.g. >60°C) until homogeneously mixed. Cool to ambient temperature while mixing and/or high shear in-line mixer.

The resulting formulation is a homogeneous emulsion with excellent storage and operational stability.

Variations and extensions

Non-phospholipid components (B1) may be substituted as detailed above. Hexadecyltrimethylammonium bromide (B2) may be substituted by Hexadecyltrimethylammonium chloride (CAS 112-02-7).

(2-hydroxypropyl)-beta-cyclodextrin (B3) may be substituted or used in combination with other cyclodextrin-based compounds as detailed above. Furthermore, other sugars, oligosaccharides and polysaccharides may be used as substitutes for or in combination with the cyclodextrin-based compounds. Silver particle formulation (1):

An illustrative silver formulation composition is as follows: Preparation procedure:

The principle of the preparation is to surround the silver-silica microcomposite with polymeric resin matrix that contains a cationic surfactant component. The close association of the cationic surfactant component and the polymeric matrix is advantageous from a perspective of formulation stability and also efficacy of the formulated product. The initial step of the procedure involves blending the silver-silica microcomposite into a solution of the matrix components (A1 through A6 in the above table) followed by high intensity mixing through bead milling (ca. 8 hours).

The matrix preparation procedure generates a homogeneous mixture where the matrix components penetrate into and surround the silver-silica microcomposite particles. The balance of ingredients (surfactants and viscosity modifier components) are formulated together prior to introduction of the matrix preparation via in-line high shear mixer.

The resulting formulation is a homogeneous dispersion with excellent storage and operational stability.

Silver particle formulation (2): Another illustrative silver formulation composition is as follows:

* As part of silver chloride - titanium dioxide microcomposite particle.

Preparation procedure in more detail:

The silver chloride - titanium dioxide microcomposite particles are, generally speaking, prepared as follows:

1. Titanium dioxide particles are suspended in aqueous solution of silver nitrate;

2. Addition of sodium chloride leading to precipitation of silver chloride on the surface of the titanium dioxide particles;

3. Addition of other formulation components such as surfactants and stabilizers.

More specifically, the silver chloride - titanium dioxide microcomposite particles used here were processed using the following recipe:

The principle of the preparation is to surround the silver chloride - titanium dioxide microcomposite with either a cationic surfactant or non-ionic surfactant component. Optionally a polymeric matrix component may be added to give additional material surrounding the microcomposite. The close association of the cationic surfactant or non- ionic surfactant components and the polymeric matrix is advantageous from a perspective of formulation stability and also efficacy of the formulated product.

The initial step of the procedure involves blending the silver chloride - titanium dioxide microcomposite and additional titanium dioxide particles into a solution of the matrix components (ethylene glycol, alcohol C16C18, ethoxylated, and polysiloxane) followed by high intensity mixing through bead milling (ca. 8 hours).

The matrix preparation procedure generates a homogeneous mixture where the matrix components penetrate into and surround the silver chloride - titanium dioxide microcomposite particles.

The balance of ingredients (surfactants and viscosity modifier components, i.e. ethylene glycol, ethyl cellulose (thickener) and additional polysiloxane defoamer are formulated together prior to introduction of the matrix preparation via in-line high shear mixer. The resulting formulation is a homogeneous dispersion with excellent storage and operational stability.

More specifically the following process steps can be used to manufacture silver-containing formulations where the silver material is particulate in nature:

The Phase B formulation is the larger proportion of the final blend weight.

The Phase A formulation is prepared as a particle concentrate and generally forms less than 50% of the final formulation weight. The Phase A formulation component typically forms between 10% and 40% of the final formulation weight.

The silver materials may optionally be added to the Phase A preparation as a dry powder or as an aqueous pre-suspension. If a pre-suspension form is used, corresponding adjustments are made to the water balance and mixture proportions to accommodate this.

Example silver formulations indicating example compositions of Phase A and Phase B preparations together with the blending proportions for achieving the final product composition are as follows:

Example 1 : Silver-silica basis

Blend ratio

^* silver - silicon dioxide composite

Example 2: Silver-silica basis

Blend ratio

^* silver - silicon dioxide composite

Example 3: Silver-silica basis

Blend ratio

^* silver - silicon dioxide composite Example 4: Silver chloride - titania basis

Blend ratio

^* silver chloride - titanium dioxide composite

Example 5: Silver chloride - titania basis

Blend ratio

^* silver chloride - titanium dioxide composite

Example 6: Silver chloride - titania basis

Blend ratio

^* silver chloride - titanium dioxide composite Total product formulation (1):

A typical example formulation for the combined product formulation, using the above first silver-silica formulation is as follows:

Preparation procedure The product formulation is produced by blending the silver formulation and the vesicle formulation together with addition of water (that may optionally contain additional auxiliary or functional components).

The blending procedure (with simple vessel agitation) proceeds in the following order. The blending ratio reflects the ratios needed to produce the exemplar product composition above.

Steps 2 and 3 may optionally be reversed. The resulting formulation is a homogeneous emulsion with excellent storage and operational stability.

Total product formulation (2): Another example formulation for the combined product formulation, using the above first, silver chloride - titanium dioxide formulation is as follows:

^* As part of silver chloride - titanium dioxide microcomposite particle.

Preparation procedure The product formulation (2) is produced by blending the silver formulation and the vesicle formulation together with addition of water (that may optionally contain additional auxiliary or functional components).

The blending procedure (with simple vessel agitation) proceeds in the following order. The blending ratio reflects the ratios needed to produce the exemplar product composition above.

Steps 2 and 3 may optionally be reversed. The resulting formulation is a homogeneous emulsion with excellent storage and operational stability.

Total product formulation (3):

Another example formulation for the combined product formulation, using the above first, silver chloride - titanium dioxide formulation is as follows:

^* As part of silver chloride - titanium dioxide microcomposite particle.

Preparation procedure

The product formulation (3) is produced by blending the silver formulation and the vesicle formulation together with addition of water (that may optionally contain additional auxiliary or functional components). The blending procedure (with simple vessel agitation) proceeds in the following order. The blending ratio reflects the ratios needed to produce the exemplar product composition above.

Steps 2 and 3 may optionally be reversed. The resulting formulation is a homogeneous emulsion with excellent storage and operational stability. Product use:

The product formulation may be applied onto fabric substrates through standard industrial processes (e.g. padding, dipping, coating, spraying, printing etc.).

Typical addition rate to the fabrics is in the range of 2% to 30% (weight of fabric basis).

A preferred range for treatments is 5% to 20% (weight of fabric basis) with dosing dependent on application and functional requirements.

Product effect:

The product exhibits excellent antibacterial properties for example as tested according to ISO 20743 (Textiles - Determination of antibacterial activity of antibacterial finished products).

Two fabrics were treated with the product formulation (1 ) applied to the fabric at 20% (weight of fabric basis). The fabrics were treated using a lab padder and lab dryer (Drying at 120°C for 2 minutes). Fabric A was a 100% polyester woven fabric. Fabric B was a 100% cotton knit fabric. An untreated 100% polyester woven fabric was used as a control. The ISO 20743 method was used to evaluate the antibacterial efficacy of both fabrics against Staphylococcus aureus (ATCC 6538P) and Klebsiella pneumoniae (ATCC 4352). Both fabrics achieved >5 log reduction of bacteria (>99.999% reduction). The product exhibits excellent antiviral properties for example as tested according to ISO 18184 (Textiles — Determination of antiviral activity of textile products).

A 100% polyester knit fabric was treated with the product formulation (3) applied to the fabric at 10% (weight of fabric basis). The fabric was treated using a lab padder and lab dryer (Drying at 120°C for 2 minutes). The ISO 18184 method was used to evaluate the antiviral efficacy of the fabric against Betacoronavirus 1, strain OC43 (ATCC VR-1558). Testing was conducted on samples initially and also after 15x and 30x laundry cycles at 60°C (according to ISO 6330) The fabric showed >3 log reduction of Betacoronavirus initially and >2 log reduction after 30x laundry cycles.