Application of Aqueous Dispersion of Magnesium Compound in Functional Finishing of Textiles

Abstract

The present invention provides a composition and an aqueous dispersion comprising magnesium oxide, wherein the magnesium oxide is used as the sole active agent or in combination with ammonium phosphate / polyammonium phosphate to impart antibacterial and / or antiviral properties to textile products. The present invention further provides a method for preparing the composition and the aqueous dispersion, and a method for using the composition and the aqueous dispersion for textile finishing.

Description

Technical Field

[0001] The present invention relates to aqueous dispersions comprising magnesium compounds, in particular magnesium oxides of specific grades, said magnesium compounds being present alone or in combination with ammonium phosphate or ammonium polyphosphate. The provided dispersions are used in the field of textile functional finishing, in particular as antiviral and antibacterial textile finishing agents. Background Art

[0002] Commercially used polymers contain additives to improve processing properties and to modify the properties of the polymers. For example, textile products contain flame retardants to increase fire resistance and also contain biocides to eliminate or at least inhibit the deposition and growth of microorganisms on or in the fabric. Different techniques are used to incorporate the additives into the finished textile products. For example, the additives can be formulated as a solution, an emulsion or an aqueous suspension, and then the fabric is soaked with the solution, squeezed to remove the excess liquid, and then dried.

[0003] Biocides commonly used in the textile industry include organocopper compounds, organotin compounds and chlorophenols (https: / / www.fibre2fashion.com / industry-article / 27 / biocides-in-textile). As discussed by Uddin (International Journal of Textile Science, 2014 3(1A) 15:20), silver-based microbial agents and metal-based inorganic compounds such as zinc oxide, zinc salts and copper salts have also been tested in fabrics.

[0004] Other examples can be found in the patent literature. CA 1334273 describes a microbial killing composition for textiles based on certain phosphates. Treatment of polyester fabrics with an antimicrobial agent consisting of an alkyl phosphate (as a quaternary ammonium salt) and a diisocyanate is described in JP 10088482. Antimicrobial finishing of cotton fabrics soaked in ammonium sulfate and ethoxylated alkylamines is described in CN 105297401.

[0005] There is an interest in the development of textile finishing agents with antibacterial and antiviral activity. Such finishing agents are particularly valuable as they can assist in preventing the spread of infectious diseases and enable textile materials to be used in hospitals without frequent disinfection. Summary of the Invention

[0006] Inorganic magnesium compounds with low solubility in water, especially specific grades of magnesium oxide (magnesia, MgO) and / or magnesium hydroxide, are available in different grades on the market, designed for various industrial needs. Magnesium oxide is used in the plastics industry (e.g., as an additive in rubber and resins), the pharmaceutical industry (e.g., for the production of granules for tablets), and the steel industry (manufacture of transformer steel sheets).

[0007] The inventors have tested the activity of certain grades of MgO in textile products and have currently found that MgO itself shows antibacterial, antiviral, and slightly antibacterial effects in these products (e.g., polyester fabrics), and when MgO is supplied to the fabric in combination with ammonium polyphosphate (APP), such as ammonium aluminum polyphosphate salt, the above-mentioned effects of MgO are strongly enhanced.

[0008] Both MgO and APP are water-insoluble powders. The inventors have prepared a co-formulation that disperses MgO and APP in water with the help of conventional additives (e.g., dispersants, thickeners) in the presence of a binder (required to adhere the active compounds to the fabric). The MgO / APP aqueous co-formulation can be used to deliver the active ingredients to the fabric by conventional techniques employed in the textile industry, such as padding, coating, and soaking.

[0009] Accordingly, one aspect of the present invention is a composition comprising magnesium oxide, a surfactant, and a thickener.

[0010] In some embodiments, the magnesium oxide according to the present invention is characterized by having a d 10 particle size distribution in the range of 0.5 to 1.5 μm, a d 50 in the range of 1.5 μm to 6.0 μm, and a d 90 in the range of 5.0 μm to 45.0 μm, wherein the magnesium oxide is further characterized by having:

[0011] a) a surface area in the range of 5.0 to 25.0 m 2 / gr,

[0012] b) a loss on ignition (LOI) in the range of 0.2% to 8.0%,

[0013] c) a bulk density in the range of 0.25 to 0.50 gr / ml, and

[0014] d) a citric acid activity (CAA 40) in the range of 25 to 200 seconds.

[0015] In other embodiments, the magnesium oxide according to the present invention is characterized by having: a d 10 in the range of 0.5 to 1.5 μm, a d 50 in the range of 1.5 to 6.0 μm, and a d90 A particle size distribution ranging from 5.0 to 45 μm, a surface area ranging from 5.0 to 25.0 m 2 / gr, an LOI ranging from 0.2 to 5.0%, a bulk density ranging from 0.30 to 0.50 gr / ml, and a citric acid activity (40) ranging from 80 to 200 seconds.

[0016] In a further embodiment, the magnesium oxide according to the invention is characterized by having: d 10 ranging from 0.8 to 1.5 μm, d 50 ranging from 2.5 to 6.0 μm and d 90 a particle size distribution ranging from 10.0 to 45 μm, a surface area ranging from 5.0 to 15.0 m 2 / gr, an LOI ranging from 2.0 to 8.0%, a bulk density ranging from 0.25 to 0.35 gr / ml, and a citric acid activity (40) ranging from 100 to 200 seconds.

[0017] In a still further embodiment, the magnesium oxide according to the invention is characterized by having: d 10 ranging from 1.0 to 1.5 μm, d 50 ranging from 2.5 to 6.0 μm and d 90 a particle size distribution ranging from 10.0 to 45.0 μm, a surface area ranging from 5.0 to 10.0 m 2 / gr, an LOI ranging from 0.2 to 6.0%, a bulk density ranging from 0.3 to 0.5 gr / ml, and a citric acid activity (40) ranging from 100 to 200 seconds.

[0018] In another aspect thereof, the present invention provides an antiviral and / or antibacterial textile finishing aqueous dispersion, which comprises the composition defined herein and optionally comprises a binder. In other words, the present invention provides an antiviral and / or antibacterial textile finishing aqueous dispersion, which comprises magnesium oxide, a surfactant, a thickener, and optionally comprises a binder. The aqueous dispersion defined herein contributes to textile finishing and imparts antiviral and / or antibacterial properties to textile products.

[0019] In some embodiments, the textile finishing aqueous dispersion according to the invention comprises:

[0020] 67 to 90% by weight of water;

[0021] 2 to 20% by weight of MgO;

[0022] 0.5 to 4% by weight of a surfactant; and

[0023] 0.1 to 0.5% by weight of a thickener.

[0024] In other embodiments, the textile finishing aqueous dispersion according to the present invention comprises:

[0025] 67 to 90% by weight of water;

[0026] 2 to 20% by weight of MgO;

[0027] 0.5 to 4% by weight of surfactant;

[0028] 0.1 to 0.5% by weight of thickener; and

[0029] 1.5 to 15% by weight of binder.

[0030] In a further embodiment, the textile finishing aqueous dispersion according to the present invention further comprises ammonium phosphate or ammonium polyphosphate, and optionally comprises a binder.

[0031] In certain embodiments, the ammonium polyphosphate according to the present invention is ammonium aluminum polyphosphate.

[0032] In other embodiments, the textile finishing aqueous dispersion according to the present invention comprises:

[0033] 37 to 94% by weight of water;

[0034] 5 to 20% by weight of MgO;

[0035] 0.5 to 4% by weight of ammonium aluminum polyphosphate;

[0036] 0.5 to 4% by weight of surfactant; and

[0037] 0.1 to 0.5% by weight of thickener.

[0038] In a further embodiment, the textile finishing aqueous dispersion according to the present invention comprises:

[0039] 37 to 94% by weight of water;

[0040] 5 to 20% by weight of MgO;

[0041] 0.5 to 4% by weight of ammonium aluminum polyphosphate;

[0042] 0.5 to 4% by weight of surfactant;

[0043] 0.1 to 0.5% by weight of thickener; and

[0044] 1.5 to 15% by weight of binder.

[0045] In some embodiments, the surfactant according to the invention is an anionic surfactant or a non-ionic surfactant. In other embodiments, the thickener according to the invention is a cellulose derivative or a swellable synthetic polymer. In further embodiments, the binder according to the invention is an acrylate / ester, a polyurethane or a PVC binder.

[0046] In a further aspect thereof, the invention provides a method for finishing or treating a textile product with an antiviral and / or antibacterial aqueous dispersion as defined herein, wherein a binder is present in the dispersion.

[0047] In some embodiments, the method according to the invention imparts virus-inhibiting or antiviral properties to the textile product. In certain embodiments, the method according to the invention imparts virus-inhibiting or antiviral properties to the textile product against viruses of the Coronaviridae family.

[0048] In further embodiments, the method according to the invention imparts bacteriostatic or antibacterial properties to the textile product. In certain embodiments, the method according to the invention imparts bacteriostatic or antibacterial properties to the textile product against bacteria associated with hospital infections. In still further embodiments, the hospital infections according to the invention are associated with Staphylococcus aureus or Escherichia coli or a combination thereof.

[0049] The invention further provides the use of magnesium oxide as at least one of a virus-inhibiting textile finishing agent, an antiviral textile finishing agent, a bacteriostatic textile finishing agent or an antibacterial textile finishing agent.

[0050] The invention still further provides the use of a combination of magnesium oxide and ammonium phosphate or ammonium polyphosphate as at least one of a virus-inhibiting textile finishing agent, an antiviral textile finishing agent, a bacteriostatic textile finishing agent or an antibacterial textile finishing agent.

[0051] In another aspect thereof, the invention provides a textile product coated with an antiviral or antibacterial finishing agent comprising magnesium oxide, wherein the amount of magnesium oxide is at least 2%, such as up to 15% or 20%, relative to the weight of the textile product.

[0052] The invention still further provides a textile product coated with an antiviral or antibacterial finishing agent comprising a combination of magnesium oxide and ammonium phosphate or ammonium polyphosphate, wherein the amount of magnesium oxide is at least 2%, such as up to 15% or 20%, relative to the weight of the textile product, and the amount of ammonium phosphate or ammonium polyphosphate is at least 0.5%, such as up to 2%.

[0053] In some embodiments, the textile product according to the invention is a medical textile product, a facial mask or a fabric filter. BRIEF DESCRIPTION OF THE DRAWINGS

[0054] Figures 1A - 1B : The figure shows the weight loss (%) of the HA4 grade MgO sample during the TGA test in the temperature range up to 600 °C ( Figure 1A ) or up to 900 °C ( Figure 1B ).

[0055] Figures 2A - 2B : The figure shows the virus counts measured at different time points in the AATCC test, which uses a spunbond nonwoven 100% polypropylene 30 GSM fabric coated with an aqueous dispersion containing HA4 grade MgO (“MgO HA4”) or an aqueous dispersion containing HA4 grade MgO and APP and is inoculated with Escherichia coli phage MS2 within the first 4 hours of the test ( Figure 2A ) or throughout the duration of the test ( Figure 2B ). “Control” refers to the uncoated fabric.

[0056] Figures 3A - 3B : The figure shows the bacterial counts measured at different time points in the AATCC test, which uses a spunbond nonwoven 100% polypropylene 30 GSM fabric coated with an aqueous dispersion containing HA4 grade MgO (“MgO HA4”) or an aqueous dispersion containing HA4 grade MgO and APP and is inoculated with Staphylococcus aureus within the first 6 hours of the test ( Figure 3A ) or throughout the duration of the test ( Figure 3B ). “Control” refers to the uncoated fabric.

[0057] Figures 4A - 4C : The figure shows the bacterial counts measured at the time points specified in the AATCC test, which is carried out on polyamide-Lycra fabric samples coated with an aqueous dispersion of HA4 grade MgO in the presence of Staphylococcus aureus, where the aqueous dispersion contains AC-178 ( Figure 4A ), AC-2403 ( Figure 4B ) or AC-75032 ( Figure 4C ) and has undergone 10, 20, 35 or 50 washing cycles. “Control” refers to the uncoated fabric. Detailed Description

[0058] In its most general form, the preparation of magnesium oxide is based on the calcination of magnesium hydroxide. The temperature distribution within the calcination kiln affects the properties and activity of the resulting magnesium oxide.

[0059] Magnesium oxide grades suitable for use in the present invention are selected to meet a set of criteria, such as:

[0060] - With d 10 , d 50 and d 90 The particle size distribution (PSD) characterized by values such that d 10 ≤ 1.5 μm (e.g., 0.5 to 1.5 μm, 0.5 to 1.0 μm, or 0.8 to 1.3 μm), 1.5 μm ≤ d 50 ≤ 6.0 μm (e.g., 1.5 to 5.0 μm) and 5.0 μm ≤ d 90 ≤ 45.0 μm (e.g., 8.0 μm ≤ d 90 ≤ 45.0 μm or 5.0 μm ≤ d 90 ≤ 30 μm) (measured by laser diffraction).

[0061] - Specific surface area greater than 5.0 m 2 / gr, preferably 5.0 to 25.0 m 2 / gr., more preferably 5.0 to 15.0 m 2 / gr, even more preferably 5.0 to 10 m 2 / gr or 5.0 to 9 m 2 / gr (measured by the BET method).

[0062] - Citric acid activity (CAA 40) ranges from 25 to 200 seconds, preferably 80 to 200 seconds, e.g., 150 to 200 seconds.

[0063] - Loss on ignition (LOI, a measure of the magnesium hydroxide residue) is in the range of 0.2 to 8.0 wt%, e.g., 4.0 to 8.0 wt%, preferably 0.2 to 3.0 wt% or 0.2 to 1.0 wt%.

[0064] - Bulk density is in the range of 0.25 to 0.50 gr / ml, e.g., 0.30 to 0.40 gr / ml or 0.25 to 0.35 gr / ml.

[0065] For example, as shown below, for a specific magnesium oxide (HA4 grade) formulation tested (TGA performed at temperatures up to 600 °C), the magnesium hydroxide residue (TGA) is 0.724%, as Figure 1A shown; while for another HA4 grade magnesium oxide formulation, the magnesium hydroxide residue (TGA) is 2.073%, as Figure 1B shown (relating to TGA performed at temperatures up to 900 °C).

[0066] Grades meeting the above properties are commercially available (e.g., MgO HA4 grade, MgO SIG-SC grade, or MgO SIG-S grade from ICL-IP). An illustrative preparation method of MgO used in the present invention is provided in the following experimental section, which is based on the grinding (dry grinding) of MgO products obtained by calcining magnesium hydroxide in the temperature range of 600 to 950 °C. Alternatively, the preparation of MgO used in the framework of the present invention can be based on the wet grinding of magnesium hydroxide before the above-mentioned calcination step. Magnesium hydroxide itself can be obtained by hydrating the thermal decomposition product of magnesium chloride (Aman method) or by precipitation reaction (i.e., the precipitation reaction between magnesium chloride and alkaline reagents such as sodium hydroxide, calcium hydroxide, or ammonium hydroxide, etc.).

[0067] The physical properties of the MgO grades applicable to the present invention can be determined based on methods well known in the art, such as those detailed in the following examples.

[0068] In one aspect thereof, the present invention provides an antibacterial and / or antiviral textile finishing aqueous dispersion, which comprises magnesium oxide, a surfactant, a thickener, and optionally a binder.

[0069] To prepare the composition of the present invention, magnesium oxide powder, a surfactant, and a thickener having the characteristics described herein are mixed by any method known to those skilled in the art. Preferred surfactants and thickeners are described below.

[0070] To prepare an aqueous dispersion of MgO, in the presence of one or more surfactants (such as a dispersant and an optionally present wetting agent), MgO powder (such as MgO HA4 grade from ICL-IP) is mixed with water on a laboratory scale with the aid of a dissolver stirrer / disperser operating at 300 to 600 revolutions per minute (rpm). Then, a thickener is added. The aqueous dispersion as defined herein may further comprise a binder, such as an acrylic binder, which is added to the dispersion last.

[0071] A stable dispersion of MgO in water is formed, wherein the content of MgO is not less than 2% by weight, for example 2 to 20% by weight, based on the total weight of the MgO dispersion. If a binder is present, the concentration of the binder is generally 1.5% to 15%. The concentration of the surfactant (such as a dispersant) is 0.5 to 4%. The concentration of the thickener is 0.1 to 0.5%. When a wetting agent is added, the concentration of the wetting agent is 0 to 0.4% (up to 0.4%). The MgO dispersion may optionally further comprise a softener and other textile additives known in the art.

[0072] Therefore, the preferred MgO aqueous dispersion of the present invention comprises (by weight percentage based on the total weight of the MgO aqueous dispersion):

[0073] 67 to 90% by weight of water, such as 70 to 80% by weight;

[0074] 2 to 20% by weight of MgO, such as 9.9 to 13.4% by weight;

[0075] 0.5 to 4% by weight of a surfactant (e.g., a dispersant), such as 0.9 to 1.5% by weight;

[0076] 0.1 to 0.5% by weight of a thickening agent, such as 0.3 to 0.5% by weight; and

[0077] 1.5% to 15% by weight of an adhesive, such as 9 to 15% by weight.

[0078] It should be understood that the term "aqueous dispersion" (which may be used interchangeably with "aqueous suspension") for the purposes of the present invention refers to a dispersion of the solids (powders) and additives described herein in an aqueous carrier. The aqueous dispersion is typically characterized by a solid concentration in the range of 20% to 40% by weight of the total weight of the aqueous dispersion / suspension. The solid components include all components of the dispersion other than the aqueous carrier, such as MgO powder, APP powder (i.e., ammonium phosphate or ammonium polyphosphate, if present), adhesive, surfactant (e.g., dispersant), etc.

[0079] As detailed herein, the inventors have found that the action of MgO is strongly enhanced when supplied to a fabric in admixture with ammonium polyphosphate (APP), such as ammonium aluminum polyphosphate. Without wishing to be bound by theory, the enhanced antibacterial and antiviral properties result, inter alia, from the uniform textile coverage provided by the addition of APP to the aqueous dispersion as defined herein.

[0080] Accordingly, the present invention further provides an antibacterial and / or antiviral textile finishing aqueous dispersion as described herein, which further comprises ammonium phosphate or ammonium polyphosphate.

[0081] The ammonium phosphate or ammonium polyphosphate suitable for use according to the present invention is preferably a multivalent metal complex of ammonium polyphosphate as described in WO 2016 / 199145, in particular the reaction product of: concentrated phosphoric acid (superphosphoric acid); a multivalent metal source (e.g., an aluminum compound, such as Al(OH)3); and ammonium hydroxide, which can be recovered as a white, free-flowing fine powder. The above reaction product, i.e., ammonium aluminum polyphosphate or ammonium aluminum superphosphate, is in an amorphous form, with a phosphorus content of up to more than 60% by weight, such as 70 to 80% by weight, calculated as PO4 3- ; a nitrogen content of more than 8% by weight, such as 9 to 10% by weight, calculated as NH4 + ; an Al content of more than 5% by weight, such as 6 to 8% by weight; and a water content of ~5 to 10% by weight. A suitable commercially available product is from ICL-IP AG, with a particle size distribution of d 50 <5 μm, d 90 <15 μm, and d 99 <35 μm. In this text, the symbol APP is used to represent any ammonium phosphate / polyammonium phosphate, including the polyvalent metal complexes exemplified and / or described above. Among other phosphorus reagents suitable for use according to the present invention, without the need for multiple washing cycles, there are also monoammonium phosphate (MAP) or sodium pyrophosphate decahydrate (NAPP).

[0082] In a specific embodiment, the MgO / APP co-dispersion defined herein contains MgO and ammonium phosphate / polyammonium phosphate, and the ammonium phosphate / polyammonium phosphate is AG (ammonium aluminum polyphosphate).

[0083] The MgO / APP co-formulation (which can be interchangeably referred to as co-dispersion) according to the present invention can be prepared by first separately formulating or dispersing each of the above-mentioned MgO and APP. Then the resulting separate MgO and APP dispersions are combined into an MgO / APP co-formulation, i.e., in the form of a dispersion. The weight ratio of MgO:APP in the co-formulation is, for example, in the range of 5:1 to a maximum of 20:1, such as 10:1, 15:1, etc.

[0084] Alternatively, the MgO / APP co-formulation according to the present invention can be prepared by co-suspending the two water-insoluble solids in a single dispersion. Specifically, in the presence of one or more surfactants (such as dispersants and optionally present wetting agents), at a laboratory scale, with the help of a dissolver stirrer / disperser operating at 300 to 600 revolutions per minute (rpm), MgO powder (for example, MgO HA4 grade from ICL-IP) is mixed with water. APP (for example, AG from ICL-IP) is continuously and gradually added while continuing to stir. The last components added are (optional) binders (such as acrylic binders), thickeners, and optionally present softeners.

[0085] A stable dispersion / suspension of both MgO and APP in water is formed, wherein: based on the total weight of the MgO / APP dispersion, the MgO content is not less than 5% by weight, for example, 5 to 20% by weight; based on the total weight of the MgO / APP dispersion, the APP content is not less than 0.5% by weight, for example, 0.5 to 4% by weight. The concentration of the binder is 1.5 to 15%. The concentration of the surfactant (such as the dispersant) is 0.5 to 4%. The concentration of the thickener is 0.1 to 0.5%. When a wetting agent is added, the concentration of the wetting agent is 0.1 to 0.5%, and the MgO / APP dispersion can optionally further contain softeners and other textile additives known in the art.

[0086] Therefore, the present invention further provides an aqueous dispersion, which comprises:

[0087] 37 to 94% by weight of water;

[0088] 5 to 20% by weight of magnesium oxide;

[0089] 0.5 to 4% by weight of ammonium phosphate / polyphosphate;

[0090] 0.5 to 4% by weight of surfactant;

[0091] 0.1 to 0.5% by weight of thickener; and

[0092] 1.5 to 15% by weight of binder.

[0093] The preferred aqueous dispersion of the present invention comprises (weight percentages based on the total weight of the MgO / APP aqueous dispersion):

[0094] 37 to 94% by weight of water, such as 75 to 90% by weight;

[0095] 5 to 20% by weight of MgO; such as 9.9 to 13% by weight;

[0096] 0.5 to 4% by weight of ammonium polyphosphate, such as 0.9 to 2% by weight;

[0097] 0.5 to 4% by weight of dispersant, such as 2 to 4% by weight;

[0098] 0.1 to 0.5% by weight of thickener, such as 0.2 to 0.3% by weight; and

[0099] 1.5% to 15% by weight of binder, such as 5 to 10% by weight.

[0100] As is known to those skilled in the art, the amount of binder varies according to the required application. For example, when wash resistance is required, a larger amount of binder will be used. In contrast, when fabric flexibility is required, a smaller amount of binder will be used.

[0101] A binder is required to adhere magnesium oxide alone or in combination with APP to the fabric, so the binder is part of the aqueous dispersion of the present invention (although it can be added just before applying the dispersion to the fabric). Representative examples of binders suitable for textiles are described in WO2016 / 199145, including but not limited to acrylate / ester, polyurethane, and PVC binders. Preferably, the binder used in the dispersion described herein is acrylate / ester. The acrylic monomer structural units of the acrylate resin can be selected from alkyl acrylates and alkyl methacrylates (alkyl esters of acrylic or methacrylic acid), where the alkyl group is preferably a C1-C5 alkyl group, such as methyl, ethyl, propyl (e.g., n-propyl), and butyl (e.g., n-butyl). The parent acid - acrylic acid or methacrylic acid - can also be used in small amounts to obtain the resin. The acrylic monomers can be optionally functionalized. Other examples include 2-phenoxyethyl acrylate, propoxylated (2) neopentyl glycol diacrylate, polyethylene glycol diacrylate, pentaerythritol triacrylate, 2-(2-ethoxyethoxy)ethyl acrylate. Commercially available acrylate resins containing 47 to 90% solids (such as AC-170, AC-178, AC-2403, AC-75032, etc.).

[0102] The MgO or MgO / APP suspension / dispersion described herein further contains conventional additives. The main types of additives include:

[0103] One or more surfactants, namely dispersants, emulsifiers, wetting agents, combinations of dispersants / wetting agents (usually each at 0.5 to 4% by weight, e.g., each at 1.5 to 2.5% by weight);

[0104] One or more softeners (usually each at 2 to 5% by weight, e.g., each at 2 to 3% by weight);

[0105] One or more rheology modifiers, namely thickeners (usually each at 0.1 to 0.5% by weight, e.g., each at 0.2 to 0.5% by weight).

[0106] Based on the total weight of the individual suspension, a dispersant, wetting agent, or a dispersant having the necessary wetting properties is present in each individual MgO or MgO / APP suspension described herein, i.e., the concentration in each is 0.5 to 4.0% by weight (e.g., 1.5 to 2.5% by weight). The dispersant can be an oligomer, polymer, or alkoxylate, as described in WO 2016 / 199145. For example, to prepare MgO and MgO / APP suspensions, based on the total weight of the MgO or MgO / APP aqueous dispersion, a polymeric anionic surfactant (e.g., from Huntsman) can be used at 2-4% by weight 2735), sodium polymethacrylate (e.g., from Vanderbilt Minerals, LLC ) or a sulfonate-based anionic surfactant (e.g., alkylaryl sulfonate, such as sodium diisopropylnaphthalene sulfonate). A polymeric dispersant, such as a nonionic acrylate copolymer (such as ) can be obtained in emulsion form.

[0107] Based on the total weight of the MgO or MgO / APP aqueous dispersion, rheology additives, such as thickeners and anti-settling agents (e.g., water-soluble nonionic polymers, such as the commonly used hydroxyethyl cellulose (HEC) thickener), are usually added at a concentration of 0.1 to 0.5 wt% in each individual suspension / dispersion.

[0108] For example, to prepare the MgO and / or MgO / APP suspensions described herein, based on the total weight of the MgO or MgO / APP aqueous dispersion, 0.1 - 0.5 wt% of the thickener Cellosize TM QP 100MH (hydroxyethyl cellulose, high molecular weight HEC, Brookfield viscosity of 1% is 4400 - 6000 cp; particle size # mesh at least 98%) is used.

[0109] In each individual suspension, based on the total weight of the MgO or MgO / APP aqueous dispersion, one or more softeners (such as ethers and polyethylene glycol esters, ethoxylated products, paraffin wax, fats or fatty acid condensates) can be further added to the suspension of the present invention at a concentration of 2 to 5 wt% in the final stage of preparation.

[0110] Other textile additives that can be used to prepare the dispersions of the present invention include, but are not limited to, defoamers, preservatives, dyes, pigments, and any mixtures thereof.

[0111] As detailed herein, the present invention further provides a method for finishing or treating textile products with the antibacterial and / or antiviral aqueous dispersion defined herein, which is an aqueous dispersion comprising magnesium oxide, a surfactant, a thickener, a binder, and optionally ammonium phosphate / polyammonium phosphate.

[0112] Specifically, the present invention relates to a method that includes using any one of the aqueous dispersions described and defined herein to finish or treat textile products. The method of the present invention is used to impart at least one of the properties of inhibiting viruses, antiviral, antibacterial, or antibacterial to textile products.

[0113] The textile can be treated or coated with the dispersion described herein in any industrially acceptable manner, such as padding (a wet finishing process that involves impregnating the fabric with a preparation / dispersion and then squeezing the fabric between heavy rollers to remove any excess preparation), coating, spraying (or other means of applying the aqueous dispersion defined herein to the textile or fabric), to have antibacterial, antiviral, antimicrobial, and / or antiviral properties. The impregnated and coated fabric is typically cured at about 120 to 160 °C for 3 to 6 minutes (a heat treatment process that aims to evaporate the solvent and promote any necessary chemical reactions to fix the finishing agent on the textile / fabric). Other types of fabrics and techniques for treating fabrics with aqueous dispersions as defined herein are described in WO 2016 / 199145.

[0114] The application of the aqueous dispersion as defined herein to the textile may be affected by its manufacturer, for example, at the dyeing or finishing stage of the textile, or at a later stage (e.g., after the preparation of the textile product is completed). The application of the aqueous dispersion as defined herein to the textile is repeatable.

[0115] As described below, the aqueous dispersion of the present invention is added to the textile product or fabric in an amount effective to reduce microbial growth or at least arrest or inhibit its growth. The resulting textile product includes additives collectively referred to by the term "add-on". The "add-on" level (or percentage) refers to the total amount of additives (including inactive additives) loaded onto the treated textile product or fabric; it is calculated based on the weight difference of the fabric (i.e., the dry fabric) before and after treatment / curing. With the help of the MgO or MgO / APP aqueous suspension / dispersion as defined herein, sufficient antibacterial or antimicrobial, antiviral or antiviral properties, i.e., preventing microbial growth or reducing by 1 - 3 orders of magnitude in microbial culture as described separately in the following experimental section, were achieved at an "additive" level of 2 to 20% of the fabric weight.

[0116] Thus, in a further aspect thereof, the present invention provides a textile product treated or coated with an antiviral or antimicrobial finishing agent (aqueous dispersion) comprising magnesium oxide, a surfactant, a binder, a thickener, and optionally ammonium phosphate / polyammonium phosphate, wherein the amount of MgO is at least 2%, for example up to 15% or 20%, based on the weight of the textile product, and when APP is present, the amount of APP is at least 0.5%, for example up to 2%. The amount added to the total dry weight of the fabric by the dispersion as defined herein is 2 to 20%.

[0117] Experimental work carried out in support of the present invention has shown that MgO suspensions prepared as described herein, when applied to different types of fabric samples, exhibit bacteriostatic and slight antibacterial effects, and it can be clearly seen that the bacterial count has decreased by approximately one order of magnitude after up to 24 hours compared to the starting time point.

[0118] Strong antibacterial effects are shown in fabrics treated with a dispersion prepared as described herein containing a combination of MgO (HA4 grade) and APP( AG), since the bacterial count has decreased by approximately three (3) orders of magnitude after 24 hours compared to the starting time point (for example, as shown in Example 1).

[0119] Furthermore, the inventors have demonstrated the antiviral properties of the prepared suspensions in Example 2 and applied them to the fabrics detailed herein, which contain either MgO alone or MgO mixed with APP. After application of the above suspensions, the virus count has decreased by approximately three (3) orders of magnitude after 24 hours compared to the starting time point, which demonstrates the antiviral properties.

[0120] Accordingly, in another aspect thereof, the present invention provides the use of magnesium oxide as at least one of an antiviral textile finishing agent, an antibacterial textile finishing agent, a bacteriostatic textile finishing agent or an antimicrobial textile finishing agent.

[0121] By a further aspect, the present invention provides the use of magnesium oxide in combination with ammonium phosphate or ammonium polyphosphate as at least one of an antiviral textile finishing agent, an antibacterial textile finishing agent, a bacteriostatic textile finishing agent or an antimicrobial textile finishing agent.

[0122] In particular, the present invention relates to the use of magnesium oxide and optionally present ammonium phosphate or ammonium polyphosphate (or a textile finishing aqueous dispersion containing the above substances) as an antiviral textile finishing agent, and also relates to the use of magnesium oxide and optionally present ammonium phosphate or ammonium polyphosphate (or a textile finishing aqueous dispersion containing the above substances) as an antimicrobial textile finishing agent.

[0123] In other words, the present invention provides a method for preventing or reducing the growth of bacteria or viruses on a textile product (or a part thereof), the method comprising finishing or treating the textile product with an antiviral and / or antimicrobial aqueous dispersion comprising magnesium oxide, a surfactant, a thickener, a binder, and optionally ammonium phosphate or ammonium polyphosphate.

[0124] Accordingly, the present invention further provides a method for imparting antiviral or virus-inhibiting properties, antibacterial or bacteriostatic properties to a textile product, said method comprising treating or processing the textile product with an aqueous dispersion comprising magnesium oxide, a surfactant, a thickening agent, a binder, and optionally ammonium phosphate or ammonium polyphosphate.

[0125] As shown in the following examples, textiles treated with an aqueous dispersion (containing MgO alone or containing MgO mixed with APP) showed antibacterial and antiviral effects, where the textiles were challenged (or inoculated) with Staphylococcus aureus, Escherichia coli phage MS2, and Escherichia coli.

[0126] The growth of microorganisms known in the art is affected by microorganisms or their combinations. The present invention relates to any microorganism, including but not limited to: viruses, such as viruses of the Coronaviridae family; and bacteria, such as Escherichia coli or bacteria associated with hospital infections, such as but not limited to Staphylococcus aureus (e.g., methicillin-resistant Staphylococcus aureus) and Pseudomonas aeruginosa. The present invention may contribute to inhibiting the growth of other microorganisms, such as archaea, algae, fungi (such as yeasts and molds), protozoa, and their combinations.

[0127] As used herein, the term "reducing microbial growth" means slowing the reproduction rate, or stopping reproduction, or eliminating live microbial cells, at a ratio of, for example, about 1, 10, 15, 20, 30, 40, 50% or more up to 100% compared to an untreated textile article.

[0128] The antibacterial and / or antiviral properties (as well as virus-inhibiting or bacteriostatic properties) of the aqueous dispersion of the present invention can be determined by any method known in the art, such as by performing the AATCC 100 test method for textile testing. The AATCC 100 test method evaluates the antibacterial properties of textiles during a 24-hour contact period (which may be extended), and quantitatively assesses the biostatic (growth inhibition) or biocidal (killing of microorganisms) properties. The test method consists of sample preparation, disinfection, inoculation, incubation, washing / shaking out, and counting.

[0129] Textile finishing as defined herein involves imparting antiviral and / or antibacterial properties to textiles, including virus-inhibiting and bacteriostatic properties, respectively. The term "biocide" known in the art refers to a substance that kills microorganisms and their spores. Depending on the type of microorganism affected, biocides can be further defined as bactericides (or antibacterial agents), fungicides (antifungal agents), antiviral agents, algicides, etc. The general term "biostatic" refers to a substance that prevents the growth (reproduction) of microorganisms and their spores, including bacteriostatic substances (relating to bacteria), virus-inhibiting substances (relating to viruses), fungistatic substances, and algistatic substances.

[0130] As shown in the following examples, the aqueous dispersions of the present invention containing MgO alone or in combination with APP (MgO / APP) are applicable to a variety of textiles (fabrics or cloths), woven / knitted articles, or non-woven fabrics (e.g., for manufacturing filters such as air-conditioning filters), which are natural, synthetic, or mixtures thereof, and are composed of fibers selected from the following: wool, silk, cotton, nylon, polypropylene, linen, hemp, ramie, jute, acetate fiber, lyocell fiber, acrylic fiber, polyolefin fiber, polyamide fiber, polylactic acid fiber, polyester fiber, rayon, viscose fiber, spandex (also known as elastane fiber, such as polyamide-Lycra fiber), metal composite materials, ceramic fibers, glass fibers, carbon fibers, or carbonized composite materials, as well as any combination of the above. Exemplary textiles are woven 12% nylon 66, 88% cotton at 170 grams per square meter (GSM), spunbond non-woven fabric of 100% polypropylene at 30 GSM, 20 GSM, and Lycra fiber.

[0131] Therefore, the textile products defined herein are made of woven / knitted fabrics or non-woven fabrics. The amount (percentage) of MgO in the fabric and the amount (percentage) of APP when present (by weight) are determined based on considerations known to those skilled in the art and based on the fabric type.

[0132] The dispersions defined herein are applicable to any textile product, including but not limited to medical textiles (e.g., protective medical masks, medical filters, medical bandages, medical dressings, etc.), clothing articles (e.g., masks), fabric filters (e.g., for producing air-conditioning filters), garments, diapers, linens, decorative textiles, industrial textiles, drapery, carpets, tents, sleeping bags, toys, wall fabrics, mattresses, or upholstery.

[0133] Every day, many healthcare professionals are exposed to bacteria on their clothes. In addition, among other factors, disposable protective masks can be replaced in whole or in part with washable textile product masks.

[0134] Therefore, the aqueous dispersion defined herein is particularly applicable to medical textiles such as masks.

[0135] As further shown in the attached examples, within the first 6 hours of the test, the aqueous dispersions containing MgO alone or in combination with APP exhibited a significant antibacterial effect ( Figure 3A ). Then, a slow increase in the bacterial count was observed ( Figure 3B), Nevertheless, it was significantly lower than the increase in bacterial count observed in the control measurement, showing an overall antibacterial effect. Importantly, the antibacterial effect observed was stable during the remaining period of the test, i.e., up to 48 hours.

[0136] Similar effects were observed when the textiles were inoculated with Escherichia coli phage MS2, where it was demonstrated that within the first 4 hours of the test, the aqueous dispersions containing either MgO alone or in combination with APP had a significant antiviral effect ( Figure 2A ). However, in this case, a continuous further decrease in virus count (antiviral effect) could be observed throughout the entire test period up to 24 hours.

[0137] The above results demonstrate the durability of the textiles coated with the aqueous dispersions described herein (containing either MgO alone or in combination with APP), which are able to withstand multiple washing cycles and can be used as antibacterial / antiviral and / or antimicrobial / antiviral textile products for a duration of 2 to 24 hours prior to cleaning or disinfecting the textile product.

[0138] The present invention will be further described and illustrated by the following examples.

[0139] Examples

[0140] Materials

[0141] The materials used in the following examples for preparing the formulations (aqueous dispersions) are listed in Table 1 (FR is the abbreviation for flame retardant):

[0142] Table 1: Materials

[0143]

[0144] Methods

[0145] Fabric Coating (Application): Padding treatment of fabrics with a preparation (interchangeably referred to as "aqueous dispersion"). Padding is carried out using a padding mangle (Rapid HORIZONTAL PADDING MANGLE - Air - Pad), where the preparation is placed between the two rollers of the padding mangle and the fabric is passed through the two rollers to impregnate both sides of the fabric, so that the preparation is adsorbed into the fabric, and the fabric is squeezed to the desired moisture content by adjusting the pressure on the rollers. Another method is to use a knife to roll - back coat only one side of the fabric. The coated fabric is cured at 160 °C for 4 minutes, washed 10 times at 60 °C according to AATCC Standard Practice for Home Laundry or washed once, 20, 35 or 50 times (as shown below) and completely dried, and tested according to AATCC Test Method 100 - 2019: "Antimicrobial Finishes on Textile Materials", details are as follows.

[0146] AATCC Test Method 100 - 2019 : The AATCC 100 method is the standard for antimicrobial fabric performance in the US textile industry and consists of six key steps: preparation of fabric samples (e.g., as described above), disinfection (e.g., in an autoclave at 1.2 atmospheres and a temperature of 121 °C for 20 minutes), inoculation by applying a microbial suspension (e.g., applying 1 ml at 1x10 5 CFU / ml on the fabric), incubation at 37 °C for the required incubation period (e.g., approximately 20 minutes to approximately 48 hours), washing / shaking out (e.g., by applying a neutralization buffer on the fabric sample and collecting the culture with the neutralization buffer), and counting (the formed colonies). Microorganisms are incubated under favorable conditions to clearly show the antimicrobial properties of the test fabric.

[0147] Specifically, the test is carried out as follows: Samples are prepared by padding the fabric with the above - mentioned preparation (aqueous dispersion) and cutting the fabric into 4.8 cm circular pieces. Then the fabric samples are disinfected in an autoclave and then inoculated with 1 ml of a suspension of the test microorganism (e.g., Escherichia coli phage MS2, also known as Escherichia coli virus MS2 (ATCC 15597); Staphylococcus aureus (ATCC 6538); and Escherichia coli (ATCC 8739)), with a bacterial inoculation amount of 1x10 5 CFU / ml and a viral inoculation amount of 1x10 5 PFU / ml. Then the samples are incubated at 37 °C for different incubation (contact) times. At the start of the timing and other different time points (e.g., after 20 minutes, 1.5, 2, 3, 4, 5 or 24 hours), a neutralization solution (20 ml of universal neutralizer, by mixing 3 g of lecithin, 30 80, 7.84 g of Na2S2O3·5H2O, 1 g of histidine, 30 g of saponin, 1 g of tryptone and 8.5 g of NaCl were used to prepare) to wash the fabric samples. The extracted microbial culture was inoculated according to the method applicable to the relevant microorganisms. Specifically, it was inoculated at 37 °C until 48 hours.

[0148] Measurement of the Average Secondary Particle Size of Magnesium Oxide Particles : The average secondary particle size measurement of MgO was carried out as follows. Approximately 0.15 g of the sample was placed in a 50 ml dry beaker, approximately 20 ml of isopropanol was added as a dispersion medium, and the mixture was stirred with a magnetic stirrer for about 10 - 15 seconds, then dispersed in an ultrasonic homogenizer (Elmasonic P) for three (3) minutes, and the particle size distribution was measured using a laser diffraction scattering type particle size distribution analyzer (Malvern Mastersizer 2000).

[0149] Citric Acid Activity (CAA 40) : CAA 40 was measured as the time (seconds) for the weighed product of 40% to react with an equivalent volume of citric acid. For this purpose, 100 ml of 0.4 N citric acid with phenolphthalein was adjusted to 30 °C. Magnesium oxide particles (2 gr sample) were added to the resulting solution, and the solution was stirred using a magnetic stirrer. The time (seconds) from adding magnesium oxide powder to the solution until the color of the measured solution changed from colorless to pink was measured, and it was determined as the CAA value in seconds.

[0150] Measurement of Surface Area : According to the BET method (based on the method of Brunauer, Emmett, and Teller), surface area analysis was measured using a Quantachrome NOVA e2000 instrument with the multi - point BET method.

[0151] Measurement of Apparent Density : The sample was gently poured into a 250 ml receiver until it reached the 250 ml mark to measure the apparent density. The weight of the contents of the receiver was measured. Apparent density (g / ml) = mass of the sample in the receiver (gr): volume of the receiver (250 ml).

[0152] LOI (Loss on Ignition) : The LOI test was carried out as follows. The weighed sample was calcined at 1000 °C for 15 minutes. After cooling the sample in a desiccator, the sample was weighed again. LOI was calculated by the following formula: [(initial sample weight - sample weight after calcination) / initial sample weight] x 100%.

[0153] TGA (Thermogravimetric Analysis): TGA is a method of measuring the mass of a sample as a function of temperature, carried out using a TA discovery TGA5500 instrument and a 10 mg sample of the product under test. The sample is heated from room temperature to 600 °C or 900 °C in a disposable aluminum crucible, depending on the expected maximum thermal stability of the compound under test at 10 °C / min in an air or nitrogen environment.

[0154] Preparation 1: Preparation of Different Grades of Magnesium Oxide

[0155] A) Preparation of Magnesium Oxide SIG / HA4 Grade

[0156] In a reactor, a magnesium chloride (MgCl2) solution with a concentration of 400 - 550 gr / l is calcined at a high temperature (700 - 850 °C). The magnesium chloride thus decomposes into magnesium oxide (MgO) and hydrochloric acid (HCl). At a temperature of 60 - 90 °C, the magnesium oxide (MgO) is hydrated to magnesium hydroxide (Mg(OH)2). The magnesium hydroxide is washed out from the soluble salts, ground to the desired particle size, and then fed into a high-temperature (600 to 950 °C) kiln, where the magnesium hydroxide decomposes into magnesium oxide and water. This MgO grade is named "SIG" (the term "SIG" refers to magnesium oxide derived from magnesium hydroxide, characterized by a very low LOI, indicating that there is almost no hydroxide in the powder). The kiln consists of several layers, and the temperature of each layer is controlled separately. The product (powder) moves from one layer to another through rabble arms. The rotation speed of the rabble arms determines the residence time at each layer at a specific layer temperature. The analysis results of the SIG grade MgO sample are shown in Table 2 below.

[0157] Table 2: Analysis Results of MgO SIG Grade Samples

[0158] Testing Unit Specification Typical Results Analysis Based on Magnesium Oxide MgO ％ 96-100.5 99.7 Chlorine Based on Cl ppm 1000 712 <![CDATA[Boron calculated as B2O3]]> ppm 200 max 122 <![CDATA[Aluminum calculated as Al2O3]]> ppm 500 max 59 <![CDATA[Silicon calculated as SiO2]]> ppm 500 max 73 Sodium Based on Na ppm 200 max 172 Surface Area S.A. <![CDATA[m 2 / gr]]> 5 min 7.0 <![CDATA[Sulfate is calculated as SO4]]> ％ 0.4 max 0.09 Calcium Based on CaO ％ 0.5 max 0.12 <![CDATA[Iron calculated as Fe2O3]]> ppm 700 max 56 Loss on Ignition ％ 3.0 max 0.2 Bulk Density (Un-tapped) g / cc 0.25 min 0.46 Particle Size: 325 Mesh Residue (Wet Screening) ％ 25 max 5.4 Particle Size: 100 Mesh Residue (Wet Screening) ％ 5.0 max 0.3

[0159] B) Preparation of Magnesium Oxide HA4 Grade

[0160] The SIG grade obtained according to the above process is ground in a dry grinding system (jet mill or pin mill), which operates within a range of dry air pressure from 2 to 4.5 atmospheres, with a powder flow rate of 100 to 200 kg / hr. To control the particle size distribution, loss on ignition (LOI), and surface area, the jet mill is maintained at a slight negative pressure (very close to zero pressure). This grade is called HA4. The analysis results of the HA4 grade MgO sample are shown in Table 3 below.

[0161] Table 3: Analysis Results of MgO HA4 Grade Samples

[0162]

[0163]

[0164] The characteristics of the MgO HA4 grade are that d 10 is less than 1.5 microns (i.e., 10% of the particles are smaller than this size), d 50 ranges from 1.5 to 6.0 microns (i.e., 50% of the particles are smaller than this size), d 90 ranges from 8.0 to 45 microns (i.e., 90% of the particles are smaller than this size), the BET specific surface area is greater than 5.0 m 2 / g, the citric acid activity (40) ranges from 25 to 200 seconds, the loss on ignition (LOI) ranges from 0.2 to 4.0%, and the bulk density (untapped) is not less than 0.25 g / ml.

[0165] The analysis results of the HA4 grade MgO sample (subjected to TGA test) are as Figure 1A and Figure 1B shown. Figure 1A Covered temperature changes up to 600 °C and demonstrated that the sample weight remained at 99.276%, indicating that the residual amount of magnesium hydroxide was 0.724%. Figure 1B Covered temperature changes up to 900 °C and showed that the sample weight was 97.927%, indicating that the residual amount of magnesium hydroxide was 2.073%.

[0166] C) Preparation of Magnesium Oxide SIG - S Grade

[0167] The MgO SIG grade obtained by the method according to Example 1(A) was treated with steam. The resulting product was designated as the "SIG-S" grade.

[0168] D) Preparation of Magnesium Oxide SIG - SC Grade

[0169] The MgO SIG grade obtained by the method according to Example 1(A) was treated with steam and carbon dioxide. The resulting product was designated as the "SIG-SC" grade.

[0170] According to the analysis characteristics, the SIG-SC grade sample is characterized by d 10 ranging from 0.8 to 1.5 microns, d 50 ranging from 2.6 to 6.0 microns, d 90 ranging from 10.0 to 45 microns, the surface area ranges from 5.0 to 15.0 m 2 / g, the citric acid activity (40) ranges from 100 to 200 seconds, the loss on ignition (LOI) ranges from 2.0 to 8.0%, and the bulk density (tapped 10 times) ranges from 0.25 to 0.35 g / ml.

[0171] Table 4 shows some properties of various grades of MgO prepared according to Examples 1(A - D).

[0172] Table 4: Properties of MgO Samples

[0173]

[0174] CAA, citric acid activity; SA, surface area

[0175] E) Preparation of Other Magnesium Oxide Grades

[0176] Other grades of magnesia were prepared by varying the properties of the kiln (such as time, temperature, etc.) to vary the particle size distribution, surface area, and reactivity of magnesia grains. Other examples of tested MgO grades are E-10A and RA-40 (periclase mineral), which are characterized by having 2 - 12% magnesium hydroxide and / or magnesium carbonate. The characteristics of the E-10A and RA-40 MgO grades are shown in Table 5 below.

[0177] The physical properties of the SIG grade MgO prepared as described above and commercially available E-10A and RA-40 MgO are shown in Table 5 below. Magnesium hydroxide samples are provided for reference.

[0178] Table 5: Particle Size Distribution and Surface Area of MgO and Mg(OH)2 Compounds

[0179]

[0180] Preparation 2: Aqueous Dispersion of Magnesia

[0181] An aqueous dispersion of magnesia was prepared using any grade of magnesia (prepared as described above or commercially available) according to the following procedure. First, water was added. Then a liquid dispersant (such as TERSPERSE 2735) was added to the water and stirred. While stirring, the required grade of MgO powder was gradually added and stirring was continued for 30 minutes (dissolver IKA, 300 - 600 rpm). Then, an acrylic binder was added, and finally, a thickener (such as HEC QP-100MH) was added as needed to modify the viscosity.

[0182] The compositions of two exemplary HA4 grade MgO aqueous suspensions (one for knitted / woven fabrics and the other for non-woven fabrics) prepared according to the above procedure are listed in Tables 6 and 7, respectively.

[0183] Table 6: MgO Dispersion for Coating Knitted / Woven Fabrics

[0184]

[0185] Table 7: MgO Dispersion for Coating Lightweight Non-Woven Fabrics

[0186]

[0187] When adding a softening agent, the final concentration is 2% by weight.

[0188] The preparation of aqueous dispersions containing different grades of MgO (such as SIG grade, E-10A, and RA-40) is carried out according to the above procedure, for example, according to the specific amounts of the components shown in Table 6 above or as shown in the following examples.

[0189] The water content in the dispersion varies according to the water absorption capacity of the fabric type and the final addition percentage required for the fabric (approximately 2% to 20%). It is noted that the diluted formulation is suitable for coating absorbent fabrics, while the concentrated formulation is suitable for coating non-absorbent fabrics.

[0190] Preparation 3: Aqueous dispersion of ammonium polyphosphate (APP)

[0191] Ammonium polyphosphate (also referred to herein as ammonium metaphosphate or AG, 300 g) was added to a container pre-filled with water (484.5 g), a dispersant ( 2010, 12 g) and a wetting agent ( WP, 1.2 g), and stirred at a rate of 300 to 600 RPM (using an IKA dissolver). The dispersion was continuously stirred for 15 minutes, and then an acrylic binder (AC-178, 150 g) was added. Finally, a thickening agent (hydroxyethyl cellulose, Cellosize HEC QP-100MH, 0.57 g) was added. Stirring was continued for an additional 30 minutes. The concentration of ammonium metaphosphate in the dispersion was 31.6% by weight. The composition is shown in Table 8 below.

[0192] Table 8: Aqueous dispersion of ammonium metaphosphate containing 40% solids

[0193]

[0194] Preparation 4: Aqueous dispersion of MgO / APP

[0195] The formulation containing MgO powder and AG was prepared as follows. First, water was added. Then, a liquid dispersant (TERSPERSE 2735, 5.28 g) was added to the water and stirred at a rate of 300 rpm (using a dissolver). While stirring, MgO powder (48 g) was gradually added and stirring was continued for 30 minutes. Then, AG dispersion (40 g of a dispersion containing 40% solids, prepared as described in Table 8 above) was added. Next, an acrylic binder (AC-178, 54.4 g) was added. Finally, a thickening agent (HEC QP-100MH, 1 g) was added. The amounts of the components are shown in Table 9 below:

[0196] Table 9: Suspension of MgO HA4 grade and AG

[0197]

[0198] The amount of binder varies according to the desired application. For example, when wash resistance is required, a higher amount of binder is used; in contrast, when fabric flexibility is required, a lower amount of binder is used.

[0199] Preparation 5: Aqueous dispersion of Mg(OH)2 (S-10 grade)

[0200] For reference, an aqueous dispersion of Mg(OH)2 (S-10 grade) was also prepared by adding an acrylic binder, a surfactant, and a polymeric thickener to the Mg(OH)2 slurry, as detailed below.

[0201] First, solid Mg(OH)2 (60 g, ICL-IP FR-S-10) was dispersed in deionized water (219 g) with a dispersant (Tersperse 2735, Huntsman) (6.6 g), 50% acrylic binder (AC-178, B.G. polymer) (15 g), and hydroxyethyl cellulose (HEC) QP-100MH (Dow) (1 g). This dispersion was used for 50% polyester / cotton fabric.

[0202] Alternatively, solid Mg(OH)2 (60 g) was dispersed in deionized water (478 g) with a surfactant (such as TERSPERSE 2735 (6.6 g)), 50% acrylic binder (such as AC-170, B.G. Polymer) (34 g), and a thickener (such as HEC, 2 g). This dispersion was applied to 100% cotton textiles.

[0203] The compositions of the two dispersions (for coating 50% and 100% cotton fabrics) prepared as described above are shown in Table 10.

[0204] Table 10: Mg(OH)2 fabric dispersion

[0205]

[0206] Example 1: Antibacterial properties of fabrics coated with MgO HA4 alone or in combination with AG

[0207] The purpose of the study reported in this example was to evaluate the antibacterial effect of applying a dispersion containing only MgO HA4 grade to fabrics, and at the same time to evaluate the antibacterial effect of a dispersion containing MgO HA4 grade and APP ( Antibacterial effect of the (AG) combination dispersion.

[0208] For this purpose, each of the following dispersions (prepared as described above) was used to separately fill the woven 12% nylon 66, 88% cotton 170 GSM fabric samples in the manner described above: the dispersion containing HA4 grade MgO (Preparation 1), the dispersion containing AG (Preparation 2), or the dispersion containing both of these reagents (Preparation 3).

[0209] The samples were separately labeled 1A, 2A, and 3A, as shown in Table 11 below, to refer to the first experiment conducted. Additional experiments were labeled with "B", "C", etc.

[0210] Then, the fabrics were tested according to the above AATCC Test Method 100 - 2019. Briefly, the fabrics were cut into 4.8 cm discs and sterilized in an autoclave. Then, the fabric discs were inoculated with 1 ml of a suspension of bacteria (Staphylococcus aureus and Escherichia coli). At the start of the timing and after 24 hours, the discs were washed with a neutralizing solution (20 ml of the general neutralizer detailed above), and the extracted bacteria were inoculated onto an agar nutrient medium by the pour plate method. The inoculated petri dishes were incubated at 37 °C for 48 hours.

[0211] Tables 11 and 12 below show the results of two experiments conducted as described above on two different fabric types: woven 12% nylon 66, 88% cotton 170 GSM (grams per square meter); and woven 12% nylon 66, 88% cotton 170 GSM for pocketing.

[0212] Table 11: Antibacterial effect against Staphylococcus aureus and Escherichia coli

[0213]

[0214] * "Percent addition" relates to the weight percentage of the solids (MgO, APP, or their combination and all additives, such as binders) included in the dispersion in the total fabric weight.

[0215] ** "Percent MgO" relates to the weight percentage of MgO in the total fabric weight.

[0216] As can be seen from Table 11, the bacterial count on the untreated fabric (control) increased by four (4) orders of magnitude.

[0217] Magnesia had an antibacterial effect on the fabric sample 1A treated with HA4 grade MgO, and the bacterial count did not show a change after 24 hours compared to the start of the timing. The fabric sample 2A treated with AG showed a similar antibacterial effect.

[0218] However, on fabric sample 3A treated with the combination of HA4 grade MgO and AG, a strong antibacterial effect was shown, as the bacterial count decreased by approximately three (3) orders of magnitude after 24 hours compared to the starting time of timing.

[0219] Table 12 below shows other test results obtained by coating 12% nylon 66, 88% cotton 170 GSM woven for pockets with a fabric using either HA4 grade MgO alone (sample labeled 1B) or a combination of this substance and AG (sample labeled 3B) and inoculating the fabric with bacteria.

[0220] Table 12: Antibacterial effects against Staphylococcus aureus and Escherichia coli

[0221]

[0222] * "% addition" refers to the weight percentage of solids (MgO, APP or their combination and all additives such as binders) included in the dispersion in the total fabric weight.

[0223] ** "%MgO" refers to the weight percentage of MgO in the total fabric weight.

[0224] As shown in Table 12, on the untreated fabric samples (two control samples), the bacterial count increased by approximately four (4) orders of magnitude.

[0225] On the fabric sample labeled 1B, after treatment with HA4 grade MgO (7.6%), magnesia had a strong bacteriostatic effect and a relatively small antibacterial effect, and the bacterial count decreased by approximately one order of magnitude after 24 hours compared to the starting time of timing.

[0226] However, on the fabric sample labeled 3B treated with the combination of HA4 grade MgO (5.9%) and AG (1.5%), a strong antibacterial effect was shown, as the bacterial count decreased by approximately three (3) orders of magnitude after 24 hours compared to the starting time of timing.

[0227] The above results indicate that fabric coating with a dispersion containing a combination of HA4 grade MgO and AG has an antibacterial effect.

[0228] Example 2: Antiviral properties of fabrics coated with HA4 grade MgO alone or a combination of this substance and AG

[0229] The purpose of the study reported in this example was to evaluate the antiviral effect of applying a dispersion containing MgO HA4 grade to fabrics, where the dispersion contains MgO HA4 grade alone or contains a combination of MgO HA4 grade and AG.

[0230] For this purpose, a spunbond nonwoven 100% polypropylene 30 GSM fabric was coated with a dispersion containing only HA4 grade MgO (Preparation 1) or a dispersion containing a combination of HA4 grade MgO and AG (Preparation 3). Then the fabric was tested according to AATCC Test Method 100 - 2019.

[0231] Briefly, the fabric was cut into 4.8 cm discs and sterilized in an autoclave. The fabric discs were inoculated with 1 ml of suspended Escherichia coli phage MS2 (ATCC 15597). At the start of the timing and after 1.5, 2, 3, 4, and 24 hours, the discs were washed with a neutralizing solution (20 ml of the universal neutralizer detailed above), and the extracted Escherichia coli phage was inoculated according to the double - layer method (Standard Methods for the Examination of Water and Wastewater. 22nd Edition. American Public Health Association, American Water Works Association, Water Environment Federation, Section: SM 9224C).

[0232] Table 13 below shows the results obtained from the above experiment. The samples treated with MgO and with the MgO / APP dispersion are labeled 1C and 3C respectively.

[0233] Table 13: Antiviral effect against Escherichia coli phage MS2

[0234]

[0235] * Virus count is similar to the virus count obtained from the control measurement at the start of the timing.

[0236] “% MgO” refers to the weight percentage of MgO in the total fabric weight. Abbreviations: Treat., treatment; Cont., control; hr, hour.

[0237] As shown in Table 13 above, throughout the experiment, the virus count on the untreated (control) fabric samples remained at approximately the same level, as expected.

[0238] On the fabric sample labeled 1C treated with MgO (8.66%), a strong antiviral effect was observed, showing a reduction in virus count by approximately three (3) orders of magnitude after 24 hours compared to the starting time of counting. As can be seen from Table 13, the reduction in virus count was gradual during the measurement time, and there was still an obvious antiviral effect even after 24 hours of cultivation.

[0239] The fabric sample labeled 3C treated with a combination of HA4 grade MgO (7%) and AG (0.7%) showed a similar antiviral effect.

[0240] The above results indicate that fabric coating with a dispersion containing HA4 grade MgO or a combination of HA4 grade MgO and AG also provides an antiviral effect.

[0241] The antiviral activities shown in Table 13 above are also presented in graphical form, with the results obtained within the first 4 hours of the experiment shown in Figure 2A and the results obtained within 24 hours throughout the experiment shown in Figure 2B As

[0242] shown, within the first 4 hours of the experiment, fabric coating with a dispersion containing only MgO was slightly more efficient than fabric coating with a dispersion containing both reagents. However, over time (i.e., the 24-hour experiment, Figure 2A ), the dispersion containing only MgO and the dispersion containing MgO and Figure 2B AG showed similar antiviral activities. AG showed similar antiviral activities.

[0243] Example 3: Duration of antibacterial effect of fabrics coated with HA4 grade MgO alone or in combination with AG

[0244] Then, over an extended duration up to 48 hours, the antibacterial effects of fabrics coated with HA4 grade MgO were studied in the absence and presence of AG.

[0245] For this purpose, spunbond non-woven fabric 100% polypropylene 30GSM was impregnated with the dispersions detailed above. Briefly, as shown in Table 14 below, the fabric was coated with a dispersion containing only HA4 grade MgO (Preparation 1), the fabric was coated with a dispersion containing only HA4 grade MgO in the presence of a softener (Preparation 1S), or the fabric was coated with a dispersion containing HA4 grade MgO and AG (Preparation 3).

[0246] At higher addition levels, a softener is required in the dispersion. The following analysis tested whether the addition of a softener to the dispersion has any effect on the antibacterial activity of the dispersion, among other factors.

[0247] The fabrics were tested based on the above-mentioned standard AATCC Test Method 100 - 2019. Briefly, the coated fabrics were cut into 4.8 cm discs, sterilized in an autoclave, and then inoculated with 1 ml of a suspension of bacteria (Staphylococcus aureus, ATCC 6538). At the start of the timing and after 15 minutes, 60 minutes, 2, 6, 24, and 48 hours, the discs were washed with a neutralizing solution (20 ml), and the extracted bacteria were inoculated on nutrient agar at 37 °C for 48 hours. The results are shown in Table 14 below.

[0248] Table 14: Time-course of antibacterial effect against Staphylococcus aureus

[0249]

[0250] “% MgO” refers to the weight percentage of MgO in the total fabric weight. Abbreviations: Treat., treatment; soften., softener; TexFR, AG; Sam.No., sample number; Cont., control.

[0251] As shown in Table 14, within the 48-hour experiment, on the untreated (control) fabric samples, the bacterial count increased continuously by approximately four (4) orders of magnitude.

[0252] Fabrics were coated with a dispersion containing HA4 grade MgO (Sample 1D), a dispersion containing HA4 grade MgO and a softener (Sample 1SD), or a dispersion containing HA4 grade MgO and AG (Sample 3D), and as a result, a strong antibacterial effect was observed throughout the test time range, i.e., up to 48 hours.

[0253] Notably, after six hours, a moderate antibacterial effect was observed for all tested fabrics (i.e., Samples 1D, 1SD, and 3D), with the bacterial count decreasing by one to two orders of magnitude compared to the start of the timing. The reduction in the bacterial count of the above samples after six hours is also shown in graphical form in Figure 3A where only the control sample and Samples 1D and 3D are shown.

[0254] As mentioned above, a softener is required at higher addition levels. The above results indicate that the addition of a softener does not weaken the antibacterial activity of the dispersion.

[0255] In addition, as shown in Table 14 and in graphical form in Figure 3BAs shown, the bacterial count of the tested coated fabric increased slightly after six hours. However, after 48 hours, a significant reduction in the bacterial count (a 4 - 5 order of magnitude decrease) was observed compared to the control sample, indicating that the antibacterial effect was stable throughout the test period.

[0256] The above examples show that the fabric as described above exhibited strong antibacterial properties for up to 6 hours and can thus be used for at least 6 hours before washing or disinfection.

[0257] Example 4: Effect of multiple washing cycles on the antibacterial activity of MgO dispersion on fabric

[0258] The effect of multiple washing cycles on fabrics coated with HA4 - grade MgO dispersion was further examined. For this purpose, three different HA4 - grade MgO aqueous dispersions were prepared according to the above - mentioned method, and each aqueous dispersion contained a different binder, namely AC - 178, AC - 2403, or AC - 75032. The composition of the prepared aqueous dispersions is shown in Table 6 above in detail.

[0259] As described above, the above - mentioned dispersions were filled (respectively) on polyamide - Lycra fiber samples. After coating with various MgO dispersions, the fabric samples were cured at 160 °C for 4 minutes, washed 10, 20, 35, or 50 times and dried, and tested according to the AATCC Test Method 100 - 2019 as described above.

[0260] Briefly, the fabric was cut into 4.8 - cm discs, sterilized in an autoclave, and inoculated with 1 ml of suspended bacteria (Staphylococcus aureus, ATCC 6538). At the start of the timing and after 2, 5, and 24 hours, the discs were washed with a neutralizing solution (20 ml), and the extracted bacteria were inoculated on nutrient agar at 37 °C for 48 hours. Table 15 below shows the results of the above experiment.

[0261] Table 15: Antibacterial effect of HA4 - grade MgO - coated fabric against Staphylococcus aureus after multiple washing cycles

[0262]

[0263]

[0264] * The bacterial count at the start of the timing was similar to the bacterial count obtained from the control measurement at the start of the timing. “% MgO” refers to the weight percentage of MgO in the total fabric weight. Abbreviations: Treat., treatment; Sam.No., sample number; Cont., control; cycles, washing cycles.

[0265] As shown in Table 15 above, similar to the observations in the previous examples, in the absence of the MgO coating, an increase in the bacterial count was observed (specifically, an increase of four orders of magnitude).

[0266] Notably, in the presence of MgO dispersions containing various binder types (i.e., AC-178, AC-2403, and AC-75032), as shown respectively in Figure 4A , Figure 4B and Figure 4C after five (5) hours of incubation, a decrease in the bacterial count by one to two orders of magnitude was observed. This is evidence of the antibacterial effect. From this time point until the end of the experiment, the bacterial count gradually increased, but in any case, the bacterial count was observed to be at least two orders of magnitude lower than the bacterial count of the control measurement.

[0267] Analysis of the bacterial counts of various dispersions obtained under different washing conditions of 10, 20, 35, and 50 cycles showed that the number of washing cycles applied to the coated fabric had a slight effect. For example, when using the AC-178 or AC-2403 binder, as shown respectively in Figure 4A and Figure 4B 10 or 20 washing cycles were advantageous; while when using the AC-75032 binder, as shown in Figure 4C 20 washing cycles were advantageous.

[0268] Notably, as shown in Figure 4C when analyzing the bacterial counts obtained after a 24-hour incubation period, the dispersion containing the AC-75032 binder had an advantage over the other binders used, as the fabric samples behaved similarly regardless of the number of washing cycles applied to the fabric.

[0269] Furthermore, at all time points, relative to the control measurement, even after the fabric samples had undergone 50 washing cycles and in the case of using all types of dispersions, a significant bacteriostatic effect and a slight antibacterial effect were still shown. These effects were particularly evident after a five-hour incubation period.

[0270] Without wishing to be bound by theory, a slight change in the percentage of MgO added in the total fabric weight does not affect the antibacterial or bacteriostatic activity of the MgO dispersion.

[0271] Example 5 (Reference Example): Antibacterial Activity of Mg(OH)₂-Impregnated Textiles

[0272] As a reference, the use of aqueous dispersions containing different concentrations of Mg(OH)₂ as antimicrobial finishes for textiles was further examined. Two types of textiles were used: 50% / 50% polyester / cotton 175 g / m 2 and 100% cotton 200 g / m2 .

[0273] First, the fabric was coated with a Mg(OH)2 dispersion, prepared and diluted (with water) according to the above method to obtain the final (added) percentage required for Mg(OH)2, and then cured at 160 °C for 4 minutes. By filling the fabric with different dispersions, several fabrics were obtained with different total solids and Mg(OH)2 percentages. Table 16 below gives the percentage of total solids (also referred to here as the "added" percentage) and the percentage of Mg(OH)2 deposited on the fabric samples for 50 / 50 fabrics and 100% cotton fabrics.

[0274] Table 16: Percentages of total solids and Mg(OH)2 in the coated fabrics

[0275]

[0276] Then, as described above, both fabric types were tested according to AATCC Test Method 100 - 2019 by inoculating the fabrics with Staphylococcus aureus (ATCC 6538).

[0277] For both fabric types, the percentage of bacteria reduction increased with the increase in the amount of Mg(OH)2 in the fabric. As shown in Table 17 below, for 50% / 50% polyester / cotton fabrics, the percentage of bacteria reduction increased from 0 at 2.36% Mg(OH)2 content to 83.4% reduction at 8.9% Mg(OH)2 content. On the control fabric, a 0.5 order of magnitude increase in bacterial growth was observed (data not shown).

[0278] Table 17: Reduction in bacterial count (%) of Staphylococcus aureus on 50 / 50 woven cotton polyester coated with Mg(OH)2 dispersion after 24 hours of incubation

[0279] <![CDATA[Mg(OH)2 (% in textiles)]]> Bacteria Reduction (%) 2.36 0.0 4.8-5.1 60.7 5.65-6.75 72.4 7.2 77.6 8.9 83.4

[0280] Filling the same fabric types with a further Mg(OH)2 - containing dispersion reduced the bacterial count, as shown in Table 18:[[]]

[0281] Table 18: Reduction in bacterial count (%) of Staphylococcus aureus on 50 / 50 woven cotton polyester coated with Mg(OH)2 dispersion after 24 hours of incubation

[0282] <![CDATA[Mg(OH)2 (% in textiles)]]> Bacteria Reduction (%) 6.53-7.59 60.69 7.60-8.7 81.92

[0283] In addition, after 5 washing machine cycles, the antibacterial activity of 100% cotton knitted fabrics filled with a Mg(OH)2 - containing dispersion is shown in Table 19:[[]]

[0284] Table 19: Percentage reduction (%) in the bacterial count of Staphylococcus aureus on 100% cotton knitted fabric containing Mg(OH)2 after 5 washing machine cycles and 24 hours of incubation time

[0285]

[0286] In additional experiments on 100% cotton fabrics filled with a dispersion containing Mg(OH)2 after several washing machine cycles, the results are shown in Table 20 below. The percentage reduction in bacteria increased from 75.4% at 4.3% Mg(OH)2 content in the textile to 98.9% reduction at 12.8% Mg(OH)2 content in the textile. In contrast, the control fabric samples showed a two-order-of-magnitude increase in the number of bacteria.

[0287] Table 20: Percentage reduction in the bacterial count of Staphylococcus aureus on 100% cotton knitwear containing Mg(OH)2 after 24 hours of incubation time

[0288] <![CDATA[Mg(OH)2 (% in textiles)]]> Bacteria Reduction (%) 4.3 75.4 5.2-6 91.6 6.6-7.1 97.0 12.80 98.9

[0289] Example 6: Antibacterial activity of 100% cotton knitted fabrics coated with different magnesium oxide compounds

[0290] Then, the antibacterial activity of aqueous dispersions containing different grades of magnesium oxide coated on 100% cotton knitted fabrics against Staphylococcus aureus (ATCC 6538) was tested. As a reference, the antibacterial activity of fabrics coated with an aqueous dispersion containing Mg(OH)2 was also determined.

[0291] First, different aqueous dispersions (60 g each) of Mg(OH)2 or MgO were prepared generally as described above, where MgO was of SIG, E-10A, and RA-40 grades, and Mg(OH)2 was of S-10, HD-5, and HD-12 grades (Table 6).

[0292] These dispersions were filled into 100% cotton textiles, and the fabrics were cured at 160 °C for 4 minutes. The percentage of Mg(OH)2 / MgO deposited on the fabric samples was 5% to 10%, as detailed in Table 21 below. The antibacterial activity of the test fabrics was tested without washing the coated and cured fabrics or after 5 washing machine cycles. The results are shown in Table 21 below.

[0293] Table 21: Percentage reduction and log reduction in the bacterial count of Staphylococcus aureus on 100% cotton knitted fabrics containing Mg(OH)2 or MgO after 24 hours of incubation time

[0294]

[0295] After examining Table 21, it was first found that the antibacterial efficacy of all MgO grades was superior to that of the Mg(OH)2 grades. Among the three tested MgO grades, the aqueous dispersion containing MgO SIG grade had the highest efficacy against the tested bacteria.

[0296] Furthermore, in most cases, washing the fabric after the coating step had no significant effect on the properties of the fabric.

[0297] To evaluate the effect of the stability of magnesia dispersion on bacterial activity, after aging the magnesia dispersion for one week, it (i.e., the magnesium oxide dispersion) was immediately filled onto the fabric. No significant difference in the fabric antimicrobial activity of the two treated fabrics was observed (data not shown).

[0298] Example 7: Antibacterial Activity of Commercially Available Products

[0299] As another reference, the test was repeated on commercially available antibacterial socks and kitchen towels (Table 22). Briefly, the antibacterial socks and kitchen towels detailed in Table 22 below were inoculated with Staphylococcus aureus using the method for magnesia-coated fabrics detailed above. As shown by the results presented in Table 22 below, only the active ingredient triclosan (kitchen towel with the product name "Ultra-Fresh NM-V2") had antibacterial activity similar to that of MgO.

[0300] Table 22: Percentage reduction and log reduction of bacterial counts of Staphylococcus aureus on silver socks, towels and triclosan towels after 24 hours of incubation

[0301]

[0302] As an additional reference, the test was repeated on commercially available fabrics containing zinc oxide or copper, which were used for the preparation of face masks among other uses. These fabrics were compared with the spunbond nonwoven polypropylene 30GSM filled with the dispersion containing MgO prepared as described above.

[0303] The results of the ATCC test conducted in the presence of Escherichia coli phage MS2 are shown in Table 23 below. It can be clearly seen from Table 23 below that, compared with the control or commercially available products of zinc oxide-based face masks or copper (nonwoven fabric)-based face masks, the spunbond nonwoven polypropylene 30GSM fabric filled with the dispersion containing MgO was the most effective in reducing virus counts after 24 hours of incubation.

[0304] Table 23: ATCC test with Escherichia coli phage MS2 on commercially available products and spunbond nonwoven polypropylene 30GSM

[0305]

[0306] Example 8: Antibacterial Activity of Dispersions Containing Different Grades of Magnesium Oxide Coated on 65% Polyester 35% Cotton Fabric

[0307] In addition to the above experimental results, textile formulations of various MgO grades (i.e., HA4, SIG-S, and SIG-SC MgO grades, prepared as described above) were further prepared. Specifically, when preparing the dispersions listed in Table 6 above, 27.2 and 1.44 gr of AC-2403 (adhesive) and HEC (thickener) were used, respectively. The dispersions were allowed to mix for 2 hours.

[0308] Then, the above-described dispersions containing HA4, SIG-S, or SIG-SC, or the dispersions containing HA4, SIG-S, or SIG-SC and diluted two-fold with water, were filled on 65% polyester 35% cotton 200 gr / m 2 fabric.

[0309] As described above, the antibacterial activity of the fabric was tested using the ATCC 100-2004 method. Briefly, the fabric was cut into samples with a diameter of 4.8 cm and sterilized by autoclave. Then, two (2) samples of each test fabric were inoculated with Staphylococcus aureus bacteria (2 ml, ATCC 6538). The samples were tested at the starting time (0) and after 24 hours of incubation. At this time, a neutralizing agent (20 ml) was added, the samples were inoculated on agar plates, and incubated at 37°C for 48 hours. The results are summarized in Table 24 below.

[0310] Table 24: Antibacterial Activity of Dispersions Containing Different MgO Grades Coated on 65% Polyester 35% Cotton Fabric after 24 Hours of Incubation

[0311]

[0312] * “% addition” refers to the weight percentage of the solids (MgO, APP, or their combination and all additives, such as adhesives) included in the dispersion in the total fabric weight.

[0313] ** “% MgO” refers to the weight percentage of MgO in the total fabric weight.

[0314] As shown in Table 24, on the fabric without MgO treatment, the bacterial count increased by three (3) orders of magnitude.

[0315] Fabric samples treated with HA4 grade MgO (for obtaining percentages of 7.35% and 3.71% in the fabric) and fabric samples treated with SIG-S grade MgO (for obtaining a percentage of 5.05% in the fabric) showed that magnesia has a strong antibacterial effect, and no change in bacterial count was observed after 24 hours compared to the starting time point.

[0316] Fabric samples treated with SIG-S and SIG-SC grade MgO respectively (final percentages being 9.36% and 8.76% respectively) showed a strong biostatic effect and a slight antibacterial effect, with a reduction in bacterial count by one order of magnitude after 24 hours compared to the starting time point.

[0317] Notably, fabric samples treated with SIG-SC grade MgO (final percentage being 4.31%) showed a strong antibacterial effect, with a reduction in bacterial count by four (4) orders of magnitude after 24 hours compared to the starting time point.

[0318] Example 9: Antibacterial Activity of a Dispersion Containing HA4 Grade MgO Coated on One Surface of a 100% Polypropylene Nonwoven Fabric

[0319] Next, the antibacterial effect of the dispersion containing HA4 grade MgO was tested. The dispersion containing HA4 grade MgO was used to obtain total addition percentages of 10.0% and 10.4%. The dispersion was prepared as detailed above (Table 6).

[0320] In this example, the dispersion was applied only to one of the fabric surfaces (by back coating, the surfaces are referred to as surface "A" or "B", i.e., only on surface A or only on surface B), and the antibacterial effects of the treated fabrics were compared. Table 25 below shows the results of these experiments.

[0321] Table 25: Bacterial Count of Staphylococcus aureus (ATCC6538) on 100% Polypropylene Fabrics Coated with MgO HA4 Grade Dispersion

[0322]

[0323] As shown in Table 25, an increase in bacterial count by two orders of magnitude was observed on fabric samples without magnesia treatment (control).

[0324] Fabric samples treated with HA4 grade MgO (addition percentages of 10.0% or 10.4%) showed that magnesia has a strong antibacterial effect, and no change in the number of bacteria was observed after 24 hours compared to the starting time point.

[0325] Furthermore, it can be seen that for the two dispersions tested, the antibacterial effect obtained when filling the dispersion on surface A is similar to that obtained when filling the dispersion on surface B, meaning that the magnesia penetrates the fabric and reaches both sides.

[0326] Similar results were obtained for 100% polypropylene fabric samples after inoculation with Escherichia coli, where one surface of the 100% polypropylene fabric samples was coated with the MgO HA4 grade dispersion (i.e., the total addition percentage was 10.0% or 10.4%) prepared as described above. Table 26 below shows the results of these experiments.

[0327] Table 26: Bacterial counts of Escherichia coli on 100% polypropylene fabric coated with MgO HA4 grade dispersion

[0328]

[0329] As can be seen from Table 26, on the fabric without magnesia treatment (control), an increase in bacterial count by four orders of magnitude was observed.

[0330] In contrast, all fabric samples treated with HA4 grade MgO showed that the magnesia had an antibacterial effect, with a relatively small change in bacterial count after 24 hours compared to the starting time.

[0331] Furthermore, it can be seen that regardless of which side the magnesia was applied, antibacterial effects were shown on both sides of the fabric, meaning that the magnesia penetrated the fabric and reached both sides.

[0332] Example 10: Effect of changing the percentage of MgO in the fabric on the antibacterial activity of the fabric coated with HA4 grade MgO dispersion

[0333] Finally, with the percentage of MgO in the fabric changed, the antibacterial effect of the aqueous dispersion containing HA4 grade MgO coated on 100% polyester non-woven fabric against Staphylococcus aureus was tested. For this purpose, the dispersions prepared as described in Table 7 above were prepared and diluted.

[0334] Table 27: Bacterial counts of Staphylococcus aureus (ATCC 6538) on 100% polyester fabric

[0335]

[0336] * “% addition” refers to the percentage by weight of the solid included in the dispersion in the total fabric weight.

[0337] ** “% Mg” and “% MgO” refer to the weight percentages of Mg and MgO respectively in the total fabric weight.

[0338] As can be seen from Table 27, on the fabric without magnesia treatment (i.e., the control sample), an increase in the bacterial count by three (3) orders of magnitude was observed.

[0339] In contrast, for the fabric samples treated with HA4 grade MgO, overall addition percentages of 7.34%, 7.30% and 6.80% were obtained, indicating that magnesia has an antibacterial effect, showing a relatively small change in the bacterial count after 24 hours compared to the starting time.

[0340] Importantly, it is noted that, as shown in the last row of Table 27, the dispersion applied to the fabric samples contained all the formulation components (i.e., binder, surfactant, thickener and water), except for the absence of magnesia. An increase in the bacterial count by three (3) orders of magnitude was observed for this fabric sample, indicating that magnesia particles are crucial for antibacterial or bactericidal activity.

[0341] Although the invention has been described using some specific embodiments, there may still be many modifications and variations. Therefore, it should be understood that the invention is not intended to be limited in any way except within the scope of the appended claims.

Claims

1. An antibacterial textile finishing aqueous dispersion, the aqueous dispersion comprising: 67 to 90% by weight of water; 2 to 20% by weight of magnesium oxide; 0.5 to 4% by weight of a polymeric anionic surfactant; 0.1 to 0.5% by weight of a hydroxyethyl cellulose thickener; and An acrylate or acrylate binder.

2. The textile finishing aqueous dispersion according to claim 1, wherein The magnesium oxide is characterized by having: d 10 a particle size distribution ranging from 0.5 to 1.5 µm, d 50 a particle size distribution ranging from 1.5 µm to 6.0 µm, and d 90 a particle size distribution ranging from 5.0 µm to 45.0 µm, a surface area ranging from 5.0 to 25.0 m 2 / gr, a loss on ignition ranging from 0.2% to 8.0%, a bulk density ranging from 0.25 to 0.50 gr / ml, and a citric acid activity CAA 40 ranging from 25 to 200 seconds, where CAA 40 is measured as the time for the reaction of 40% of the weighed product with an equivalent volume of citric acid.

3. The textile finishing aqueous dispersion according to claim 1 or claim 2, wherein The magnesium oxide is characterized by having: d 10 a particle size distribution ranging from 1.0 to 1.5 µm, d 50 a particle size distribution ranging from 2.5 to 6.0 µm, and d 90 a particle size distribution ranging from 10.0 to 45.0 µm, a surface area ranging from 5.0 to 10.0 m 2 / gr, a loss on ignition ranging from 0.2 to 6.0%, a bulk density ranging from 0.3 to 0.5 gr / ml, a citric acid activity CAA 40 ranging from 100 to 200 seconds, where CAA 40 is measured as the time for the reaction of 40% of the weighed product with an equivalent volume of citric acid.

4. The textile finishing aqueous dispersion according to claim 1, the aqueous dispersion comprising 1.5 to 15% by weight of an acrylate or acrylate binder.

5. The textile finishing aqueous dispersion according to claim 1 or claim 2, the aqueous dispersion further comprising ammonium phosphate or ammonium polyphosphate.

6. The textile finishing aqueous dispersion according to claim 1 or claim 2, wherein, The aqueous dispersion further comprises ammonium aluminum polyphosphate.

7. The textile finishing aqueous dispersion according to claim 6, comprising: 67 to 90% by weight of water; 5 to 20% by weight of magnesium oxide; 0.5 to 4% by weight of ammonium aluminum polyphosphate; 0.5 to 4% by weight of a polymeric anionic surfactant; 0.1 to 0.5% by weight of a hydroxyethyl cellulose thickener; and An acrylate or acrylate binder.

8. The textile finishing aqueous dispersion according to claim 1 or claim 2, the textile finishing aqueous dispersion comprising: 67 to 90% by weight of water; 5 to 20% by weight of magnesium oxide; 0.5 to 4% by weight of a polymeric anionic surfactant; 0.1 to 0.5% by weight of a hydroxyethyl cellulose thickener; and An acrylate or acrylate binder.

9. A method for finishing a textile product with the textile finishing aqueous dispersion according to any one of claims 1 to 8.

10. The method according to claim 9, the method imparting antibacterial or antimicrobial properties to the textile product against bacteria associated with hospital infections.

11. The method according to claim 10, wherein, The bacteria associated with hospital infections are Staphylococcus aureus or Escherichia coli or a combination thereof.

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