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Title:
METHOD FOR MERCURISATION OF CELLULOSE-CONTAINING MATERIALS FOR IMPARTING BACTERICIDAL AND VIRUCIDAL ACTIVITY TO THEM
Document Type and Number:
WIPO Patent Application WO/2022/123553
Kind Code:
A1
Abstract:
Mercurisation of a cellulose-containing carrier material imparts bactericidal and virucidal properties to this carrier material and to articles manufactured from this carrier material. The method of the invention is based on photochemical mercurisation of a cellulose-containing carrier material with water-soluble mercury-containing compound under irradiation with full-spectrum bright light. The carrier material, which contains bound mercury ions after the irradiation, is subjected to fixation by briefly immersing said carrier material in a hot aqueous solution of alkali, thereby hydrating and neutralising the mercury ions. As a result of this hydration, the bound mercury ions are reduced and become neutral giving the distinct dark colour to the carrier material. The irradiation can be carried out through punctured/perforated or slotted/cut-out templates or heat-resistant negative glass slides resulting in dark coloured images or patterns produced on the carrier material or articles thereof.

Inventors:
MILOVANOV AKIM (IL)
Application Number:
PCT/IL2021/051309
Publication Date:
June 16, 2022
Filing Date:
November 04, 2021
Export Citation:
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Assignee:
MILOVANOV AKIM (IL)
IOULIA MILOVANOV (IL)
International Classes:
A01N25/10; A01N25/34; A01N43/16; A01N59/18; A01P1/00
Domestic Patent References:
WO2015011630A12015-01-29
WO2010015801A22010-02-11
WO2011129759A12011-10-20
Foreign References:
JPH05339115A1993-12-21
CN102669179A2012-09-19
US20160150793A12016-06-02
RU2619704C12017-05-17
US20140141073A12014-05-22
US7288264B12007-10-30
Attorney, Agent or Firm:
PAPPER, Vladislav et al. (IL)
Download PDF:
Claims:
CLAIMS

1. A method for mercurisation of a cellulose -containing carrier material or article obtained from said carrier material, for imparting bactericidal and virucidal activity to said carrier material, said method comprising:

(1) providing an aqueous solution of a water-soluble mercury-containing compound, a porous substrate and the cellulose-containing carrier material;

(2) contacting said porous substrate with said aqueous solution of the mercury-containing compound or soaking said porous substrate into said aqueous solution of the mercury- containing compound;

(3) placing said carrier material of Step (1) in a direct contact with and on top of said porous substrate obtained in Step (2) (wetted with or soaked in said aqueous solution of the mercury- containing compound) and pressing said cellulose-containing carrier material to ensure rapid diffusion of the mercury ions from the porous substrate into the carrier material;

(4) placing the wet carrier material obtained in Step (3) and containing diffused mercury ions in a horizontal position and irradiating said wet carrier material with full-spectrum bright light, thereby carrying out a photochemically initiated radical reaction of the abstraction of a hydrogen atom from cellulose molecules of the carrier material, and binding said mercury ions to cellulose molecules within the carrier material, wherein said mercury ions become tightly bound to the carrier material and consequently, impart bactericidal and virucidal properties to said carrier material;

(5) intermediate rinsing of the carrier material obtained in Step (4) with running water;

(6) fixing the rinsed carrier material obtained in Step (5), which contains the bound mercury ions, by shortly immersing said carrier material into a hot aqueous solution of alkali, thereby hydrating and neutralising the bound mercury ions;

(7) washing and rinsing the carrier material obtained in Step (6) with running water several times to remove water-soluble salts and water-insoluble (precipitated) oxides of mercury- containing compounds which did not react in the photochemical reaction; and

(8) air or vacuum drying of the washed carrier material from Step (7) to obtain the ready-to-use carrier material having bactericidal and virucidal properties.

2. The method of claim 1 , wherein said metal-containing compound is selected from water-soluble salts of mercury. The method of claim 2, wherein said water-soluble salts of mercury are water-soluble mercury halides. The method of claim 3, wherein said water-soluble mercury halide is mercury chloride (HgCh). The method of claim 1 , wherein said cellulose-containing carrier material is selected from cotton fabrics, cardboard, cellophane film, polymeric film, fibre, filament, sheath, woven or non-woven fabrics, knit fabrics, or any type of fabrics or material that is used to make protective bactericidal masks, filters for air conditioners for sterilising air supplied to clean rooms or operating rooms, bactericidal underwear for soldiers and people engaged in extreme and dangerous activities, wound dressings, plasters and gauzes in surgery and therapy or in the treatment of skin burns and wounds, purulent wounds, fistulas and bedsores, in surgical drapes and overalls for medical personnel, antimicrobial packaging of sterile instruments, medicines and pharmaceuticals, dosage forms coating, household wipes for the prevention of intestinal diseases, toilet paper and facial wipes. The method of claim 1 , wherein said porous substrate is selected from filter paper, foam rubber, cloth, fabric and other water-swellable materials. The method of claim 1 , wherein said full-spectrum bright light contains UV radiation within the wavelength range of about 250-450 nm. The method of claim 1, wherein a punctured, or perforated, or cut-out, or slotted template, or a heat-resistant negative glass slide is further placed over the wet carrier material in Step (4), and the irradiation with full-spectrum bright light is carried out through said template or said heat- resistant negative glass slide to obtain the dark pattern or image on the carrier material, wherein said dark pattern or image has bactericidal and virucidal activity. The method of claim 1 , wherein the temperature of said hot aqueous solution of alkali, into which said carrier material is immersed in Step (5) for fixation is 70-80 °C. The carrier material having bactericidal and virucidal activity, obtained by the method of any one of claims 1 to 9, where said carrier material is suitable for use in protective bactericidal and virucidal masks. The carrier material having bactericidal and virucidal activity, obtained by the method of any one of claims 1 to 9, where said carrier material is suitable for use in filters for air conditioners for sterilising air supplied to clean rooms or operating rooms. The carrier material having bactericidal and virucidal activity, obtained by the method of any one of claims 1 to 9, where said carrier material is suitable for use in bactericidal underwear for soldiers and people engaged in extreme and dangerous activities. The carrier material having bactericidal and virucidal activity, obtained by the method of any one of claims 1 to 9, where said carrier material is suitable for use in wound dressings, plasters and gauzes in surgery and therapy, or in the treatment of skin bums and wounds, purulent wounds, fistulas and bedsores, and in surgical drapes or overalls for medical personnel. The carrier material having bactericidal and virucidal activity, obtained by the method of any one of claims 1 to 9, where said carrier material is suitable for use in antimicrobial packaging of sterile instruments, medicines and pharmaceuticals, dosage forms coating, household wipes for the prevention of intestinal diseases, toilet paper or facial wipes.

17

Description:
METHOD FOR MERCURISATION OF CELLULOSE-CONTAINING MATERIALS FOR IMPARTING BACTERICIDAL AND VIRUCIDAL ACTIVITY TO THEM

TECHNICAL FIELD

[0001] The present application relates to the field of material metallisation in general, and to the method for photochemical mercurisation of cellulose-containing carrier materials or products thereof for imparting them bactericidal and virucidal properties, in particular.

BACKGROUND

[0002] In recent years, the number of viral and bacteriological infections has significantly increased, which is a global threat due to their constant migration. One solution to this problem is the development of antiviral vaccines, but because of their specificity, vaccines are only effective for preventing infections caused by specific bacteria or viruses. Because vaccine production is a long and laborious process, it is often difficult to stock up on the right amount of a particular vaccine ahead of time. Therefore, there is an urgent need for agents demonstrating virucidal and bactericidal activity against a wide range of bacteria and viruses.

[0003] To solve the problem described above, inorganic bactericidal and virucidal drugs have been developed, the spectrum of which is wider than that of organic antiviral drugs. It is well known that metal ions, such as Cu(I), Cu(II), Ag(I), Hg(I), Zn (II), Bi(III), Fe(II) etc., even at relatively low concentrations, have bactericidal properties due to the oligodynamic effect arising from their toxicity on living cells, algae, mould, spores, fungi, viruses and prokaryotic and eukaryotic microorganisms. This oligodynamic effect is demonstrated, for example, by the ions of mercury, silver, copper, iron, lead, zinc, bismuth, gold, aluminium and other metals, with mercury ions being the most effective in this list. This determines the existence of a sufficient number of works on methods of obtaining metallised materials for wide applications in general and mercurised materials in particular.

[0004] All known works on the methods of metallisation of materials to give them bactericidal and antiviral properties are reduced to three main directions. The first direction is the application of metalcontaining compounds to the surface of the carrier material in the form of varnishes, paints, gels, etc., including mechanical, electrochemical, adsorption and other methods. WO 2011129759 Al, for example, proposes a method for preparing antimicrobial compositions in the form of gels containing at least five components, including a silver salt, which have a bactericidal effect. The gel obtained after evaporation is applied to the surface of the carrier material and is used for medical purposes in the treatment of bums, scars, bacterial infections, and viral/fungal infections. CN 102669179 B relates to a method for preparing a composition containing a nanosilver colloid, an organic antibacterial agent, a solvent, a polymer binder and water. This formulation applied to medical masks ensures safe handling and rapid elimination of H1N1 influenza virus and H5N1 avian influenza vims.

[0005] US 20160150793 Al relates to an additive with biocidal properties based on an active agent having antimicrobial and antifouling properties, wherein the additive corresponds to a supporting inert substrate or carrier, which has been modified with antimicrobial agents. US 20160150793 Al further provides a process for producing a surface-metalised fibre, yarn, or fabric, the process comprising feeding a continuous fibre, yam, or fabric from a feeder roller into a graphene deposition chamber containing therein a graphene dispersion and further coating it with a metal from a solution containing compounds of Co, Hg, Mg and others.

[0006] All works related to the first direction of imparting bactericidal and antiviral properties to the carrier material with the composition of metal-containing compounds applied to its surface have one common drawback: the relatively weak adhesion of metal-containing compositions to the surface of the carrier material. The compositions are relatively easy to remove when washing or rinsing the product, which significantly reduces the scope of these materials, as well as the possibility of their reuse.

[0007] The second direction of work on the metallisation of materials to impart bactericidal and antiviral properties to them is the encapsulation, intercalation, saturation or modification of the carrier material with nanoparticles or metal ions. RU 2619704 Cl describes a method for producing a textile material with antibacterial properties for workwear, which includes the process of treating the material with a high-frequency capacitive discharge in a low-temperature plasma at reduced pressure, followed by impregnation with a colloidal aqueous solution of silver nanoparticles and drying. The disadvantages of the method include a relatively narrow applicability (the method is applicable only for cotton and modified cotton fabrics), as well as technological cumbersomeness.

[0008] US 20140141073 Al describes a method for imparting antiviral properties to a hydrophilic polymeric material, which includes preparing a suspension of a hydrophilic polymer, dispersing a mixture of copper ions powder containing copper oxide and copper oxide in this suspension, and then extrusion or moulding the suspension to form a hydrophilic polymeric material. In this case, the waterinsoluble particles that release the Cu(I) and Cu(II) ions are directly and completely encapsulated in the hydrophilic polymeric material. The disadvantages of this method include both its technological cumbersomeness and the fact that the composite obtained in this way requires further refinement on the production line.

[0009] US 7288264 Bl provides a combination of an adherent antimicrobial coating including a nitrogen-containing polycationic polymer matrix immobilised on a material surface, and biocidal nonleaching metallic materials bound to the matrix. The antimicrobial materials contain a combination of organic materials that form the matrix immobilised on the surface of the product due to covalent bonds and ionic interactions. The antimicrobial coating does not release the metallic materials for at least five days. The main disadvantage of all the works in the second direction is the relatively weak chemical bond of metals or related compounds intercalated into the carrier material with the matrix, which leads to a decrease in the duration of their bactericidal action, as well as to their undesirable leakage into the environment.

[0010] In general, bactericidal properties of various metals are well known, in particular, mercury, copper, silver, platinum and gold. Metallisation with the last three is economically impractical because of their very high cost. In addition, silver coating of the support material is unstable.

[0011] An attempt was also made to metallise cellulose-containing supports with copper using the proposed method, but to no avail. Since the radius of the copper ion is much smaller than the radius of the mercury ion, the binding energy of the Cu ligand is much higher than that of the Hg ligand. The copper ion attracts an electron of the ligand so strongly that it strips this electron away from the ligand. As a result, the copper ion is reduced, thus passing to a lower oxidation state. The copper ion is not bound (or poorly bound) to the cellulose molecule and is easily washed out by washing the cellulose carrier with water and treating with alkali. Consequently, the set goal of rigidly binding the metal ion to the carrier material is not achieved.

[0012] In view of the above, there is a long-felt need for an industrial carrier material mercurisation process that is simple, economically viable, and versatile for a wide range of bactericidal and virucidal materials.

SUMMARY

[0013] The present invention relates to a method for mercurisation of a cellulose-containing carrier material or article obtained from said carrier material, for imparting bactericidal and virucidal properties to said carrier material, said method comprising:

(1) providing an aqueous solution of a water-soluble mercury -containing compound, a porous substrate and the cellulose-containing carrier material;

(2) contacting said porous substrate with said aqueous solution of the mercury-containing compound or soaking said porous substrate into said aqueous solution of the mercury-containing compound;

(3) placing said carrier material of Step (1 ) in a direct contact with and on top of said porous substrate obtained in Step (2) (wetted with or soaked in said aqueous solution of the mercury-containing compound) and pressing said cellulose-containing carrier material to ensure rapid diffusion of the mercury ions from the porous substrate into the carrier material;

(4) placing the wet carrier material obtained in Step (3) and containing diffused mercury ions in a horizontal position and irradiating said wet carrier material with full-spectrum bright light, thereby carrying out a photochemically initiated radical reaction of the abstraction of a hydrogen atom from cellulose molecules of the carrier material and binding said mercury ions to cellulose molecules within the carrier material, wherein said mercury ions become tightly bound to the carrier material and consequently, impart bactericidal and virucidal properties to said carrier material;

(5) intermediate rinsing of the carrier material obtained in Step (4) with running water;

(6) fixing the rinsed carrier material obtained in Step (5), which contains the bound mercury ions, by shortly immersing said carrier material into a hot aqueous solution of alkali, thereby hydrating and neutralising the bound mercury ions;

(7) washing and rinsing the carrier material obtained in Step (6) with running water several times to remove water-soluble salts and water-insoluble (precipitated) oxides of mercury-containing compounds which did not react in the photochemical reaction; and

(8) air or vacuum drying of the washed carrier material from Step (7) to obtain the ready-to-use carrier material having bactericidal and virucidal properties.

[0014] The selective mercurisation of the carrier material to obtain a bactericidal or virucidal image on this carrier material or article obtained from said carrier material can also be performed in all steps of the method (1-8). However, in Step 4, light irradiation is performed through a negative slide or slotted stencil. DETAILED DESCRIPTION

[0015] In the following description, various aspects of the present application will be described. For purposes of explanation, specific details are set forth in order to provide a thorough understanding of the present application. However, it will also be apparent to one skilled in the art that the present application may be practiced without the specific details presented herein. Furthermore, well-known features may be omitted or simplified in order not to obscure the present application.

[0016] The term "comprising", used in the claims, is "open ended" and means the elements recited, or their equivalent in structure or function, plus any other element or elements which are not recited. It should not be interpreted as being restricted to the means listed thereafter; it does not exclude other elements or steps. It needs to be interpreted as specifying the presence of the stated features, integers, steps or components as referred to, but does not preclude the presence or addition of one or more other features, integers, steps or components, or groups thereof. Thus, the scope of the expression "a composition comprising x and z" should not be limited to compositions consisting only of components x and z. Also, the scope of the expression "a method comprising the steps x and z" should not be limited to methods consisting only of these steps.

[0017] Unless specifically stated, as used herein, the term "about" is understood as within a range of normal tolerance in the art, for example within two standard deviations of the mean. In one embodiment, the term "about" means within 10% of the reported numerical value of the number with which it is being used, preferably within 5% of the reported numerical value. For example, the term "about" can be immediately understood as within 10%, 9%, 8%, 7%, 6%, 5%, 4%, 3%, 2%, 1%, 0.5%, 0.1%, 0.05%, or 0.01% of the stated value. In other embodiments, the term "about" can mean a higher tolerance of variation depending on for instance the experimental technique used. Said variations of a specified value are understood by the skilled person and are within the context of the present invention. As an illustration, a numerical range of "about 1 to about 5" should be interpreted to include not only the explicitly recited values of about 1 to about 5 , but also include individual values and sub-ranges within the indicated range. Thus, included in this numerical range are individual values such as 2, 3, and 4 and sub-ranges, for example from 1-3, from 2-4, and from 3-5, as well as 1, 2, 3, 4, 5, or 6, individually. This same principle applies to ranges reciting only one numerical value as a minimum or a maximum. Unless otherwise clear from context, all numerical values provided herein are modified by the term "about". Other similar terms, such as "substantially", "generally", "up to" and the like are to be construed as modifying a term or value such that it is not an absolute. Such terms will be defined by the circumstances and the terms that they modify as those terms are understood by those of skilled in the art. This includes, at very least, the degree of expected experimental error, technical error and instrumental error for a given experiment, technique or an instrument used to measure a value.

[0018] As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items. Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the specification and relevant art and should not be interpreted in an idealized or overly formal sense unless expressly so defined herein. Well-known functions or constructions may not be described in detail for brevity and/or clarity.

[0019] It will be understood that when a material or a material layer, such as a carrier material is referred to as being "on", "attached to", "connected to", "coupled with", "contacting", etc., another material layer, such as a substrate material, it can be directly on, attached to, connected to, coupled with or contacting the other material layer or intervening layers may also be present. In contrast, when a material layer is referred to as being, for example, "directly on", "directly attached to", "directly connected to", "directly coupled with", “placing in a direct contact" or "directly contacting" another material layer, there are no intervening layers present. It will also be appreciated by those of skill in the art that references to a structure or feature that is disposed "adjacent" another feature may have portions that overlap or underlie the adjacent feature.

[0020] The present invention describes a method for mercurisation of a cellulose-containing carrier material or article obtained from said carrier material, for imparting bactericidal and virucidal properties to said carrier material, said method comprising:

(1) providing an aqueous solution of a mercury-containing compound, a porous substrate and the cellulose-containing carrier material;

(2) contacting said porous substrate with said aqueous solution of the mercury-containing compound or soaking said porous substrate into said aqueous solution of the mercury-containing compound;

(3) placing said carrier material of Step (1 ) in a direct contact with and on top of said porous substrate obtained in Step (2) (wetted with or soaked in said aqueous solution of the mercury-containing compound) and pressing said cellulose-containing carrier material to ensure rapid diffusion of the mercury ions from the porous substrate into the carrier material;

(4) placing the wet carrier material obtained in Step (3) and containing diffused mercury ions in a horizontal position and irradiating said wet carrier material with full-spectrum bright light, thereby carrying out a photochemically initiated radical reaction of the carrier material and binding said mercury ions to cellulose molecules within the carrier material, wherein said mercury ions become tightly bound to the carrier material and consequently, impart bactericidal and virucidal properties to said carrier material;

(5) intermediate rinsing of the carrier material obtained in Step (4) with running water;

(6) fixing the rinsed carrier material obtained in Step (5), which contains the bound mercury ions, by shortly immersing said carrier material into a hot aqueous solution of alkali, thereby hydrating and neutralising the bound mercury ions;

(7) washing and rinsing the carrier material obtained in Step (6) with running water several times to remove water-soluble salts and water-insoluble (precipitated) oxides of mercury-containing compounds which did not react in the photochemical reaction; and

(8) air or vacuum drying of the washed carrier material from Step (7) to obtain the ready-to-use carrier material having bactericidal and virucidal properties.

[0021] Unless otherwise defined, "mercurisation" in the present invention refers to the process of impregnating of cellulose-containing carrier materials with mercury atoms or ions capable of forming strong chemical bonds with these carrier materials, for imparting bactericidal and virucidal properties to these carrier materials. In fact, mercury has bactericidal and virucidal properties and can be used in the present invention due to its oligodynamic effect, which is a biocidal or virucidal effect of a metal that occurs even in low concentrations.

[0022] Unless specifically stated, the "mercury-containing compound" in the present invention refers to any water-soluble salt of mercury capable of imparting bactericidal and virucidal properties to carrier materials. Non-limiting examples of the mercury-containing compounds are water-soluble mercury halides, for example mercury chloride (HgCh).

[0023] Unless otherwise defined, the "carrier material" in the present invention refers to any industrial cellulose-containing carrier material of choice, which is required to be mercurised, depending on its application. Non-limiting examples of such material are cotton and linen fabrics, cardboard, cellophane film, polymeric film, fibre, filament, sheath, woven or non-woven fabrics, knit fabrics, or any type of fabric or material that is used to make an article having bactericidal or virucidal properties. Non -limiting examples of articles obtained from this carrier material are protective bactericidal masks, filters for air conditioners for sterilising air supplied to clean rooms or operating rooms, bactericidal underwear for soldiers and people engaged in extreme and dangerous activities, wound dressings, plasters and gauzes in surgery and therapy, for example, in the treatment of skin bums and wounds, surgical drapes and overalls for medical personnel, antimicrobial packaging of sterile instruments, medicines and pharmaceuticals, dosage forms coating, household wipes for the prevention of intestinal diseases, toilet paper, facial wipes etc.

[0024] Unless otherwise defined, the "porous substrate" in the present invention refers to any support material of choice having a high degree of porosity and hydrophilicity, and providing support for the carrier material. Non-limiting examples of such porous substrates are a filter paper, foam rubber, cloth, fabric etc.

[0025] In Step (4) of the method of the present invention, the wet carrier material which is obtained in Step (3) and contains the diffused mercury ions, is horizontally positioned and irradiated with full-spectrum bright light including UV and IR light. Unless otherwise defined, "full-spectrum bright light" is light that covers the electromagnetic spectmm from infrared to near-ultraviolet of all corresponding wavelengths. In some embodiments, the full-spectrum bright light includes a UV light with the wavelength range of approximately 250-450 nm.

[0026] If the carrier material is thick enough (such as cotton fabrics or cloth, cardboard, etc.), the temperature -dependent diffusion coefficient of the solution becomes isotropic when exposed to IR heating of the surface. In other words, heating the surface of the carrier material with the IR radiation causes the diffusion coefficient to become different in all directions, which leads to the development of an intense vertical flow of the solution. This is accompanied by the evaporation of the solvent and the accumulation of solutes in the near-surface layer of the carrier material. On the other hand, if the carrier material is thin (cellophane film, etc.), the process of accumulation of the solutes occurs throughout the entire thickness of the film.

[0027] At the same time, under the UV irradiation of the carrier material containing the diffused mercury ions, the photochemically initiated radical reaction takes place. Mechanism behind this reaction still remains unclear. However, the present inventors speculated that under the UV irradiation, as a result of the cleavage of the C-H bond of the pyranose ring, the abstraction of a hydrogen atom in the cellulose-containing material occurs with the formation of a macroradical of the cellulose molecule. This step is intermediate. Further, in the course of this photochemical reaction, mercury ions from the diffused aqueous solution are added to the cellulose radicals yielding organometallic compounds, in which the mercury ions are attached to the cellulose molecules of the carrier material via the strong mercury-carbon bond, which is highly covalent. The oxidation state of the mercury ions decreases, thereby imparting bactericidal and vimcidal properties to this carrier material. Below is the proposed mechanism for the photochemically induced radical reaction of cellulose in the presence of mercury ions together with the intermediate step:

[0028] The concentration of mercury ions in the carrier material depends on the irradiation intensity, including the power of the light source, distance to the light source and the time of exposure. The observed colour of the mercury-carrier material in Step (4) is milky white.

[0029] In step (6) of the method according to the present invention, the carrier material obtained in step (4), which contains bound mercury ions, is "fixated" (subjected to fixation) by briefly immersing said carrier material in a hot aqueous solution of alkali, thereby hydrating and neutralising the mercury ions. In this step, the hydroxyl ions of the alkali bind to the mercury ions through iondipole bonds of mainly electrostatic character, which is part of the organometallic structure shown above. As a result of this hydration, the mercury ions are reduced and become neutral, while the carrier material undergoing this photochemical reaction becomes coloured (depending on the concentration of the original solution and the exposure time). The obtained colour of the carrier material originates from the reduced mercury and supports the proposed above mechanism.

[0030] Molecules of the mercury-containing compound, such as mercury chloride (HgCh), that did not participate in the photochemical reaction in Step (4), when combined with alkali in Step (5), are converted into water-soluble alkali mercury salts and insoluble mercury oxides, while the latter are precipitated. Further intensive flushing and rinsing with running water in Step (6) leads to the washing out of all aforementioned, unreacted and not participating in the photochemical reaction, soluble and water-insoluble compounds. After air or vacuum drying in Step (7), the product is ready for use.

[0031] The method of the present invention also allows to obtain selectively mercurised materials or products/articles obtained from this carrier material, in which the irradiated areas form a dark pattern or image having grey to black colour, that also possess the bactericidal and virucidal properties. In this case, mercurisation is performed in all steps, and the irradiation in Step (4) is carried out through a punctured/perforated or slotted/cut-out template or a heat-resistant negative glass slide.

[0032] The method of the present invention has several advantages over the known methods: • Bactericidal and virucidal materials obtained by the method of the present invention have a wide spectrum of bactericidal and virucidal effects.

• Obtaining bactericidal and virucidal materials according the method of the present invention does not require changing or modifying the existing technologies for obtaining the carrier materials, since both industrial carrier materials and products from them can be successfully used in the present method.

• The method of the present invention is distinguished by technological simplicity, which makes it possible to obtain bactericidal and virucidal materials in a minimum number of simple process steps.

• The method of the present invention does not require expensive reagents and can be used in an inexpensive conveyor manufacture.

• The present method can be easily adapted to the existing manufacturing technologies, which allow large-scale production with minimal cost.

• The method of the present invention allows manufacturing of coloured bactericidal and virucidal materials or having dark pattern or image formed by the bactericidal and virucidal materials.

• The present method makes it possible to manufacture highly bactericidal and virucidal materials without almost any leachable substances in the solutions with which they contact. This imparts the materials stability in alkaline solutions and allows a large number of washes with commercial washing products.

• The mechanism of bactericidal and virucidal action of mercury-containing materials allows them to maintain stable biological activity when exposed to many microorganisms, i.e., with prolonged use.

[0033] The bactericidal and virucidal material produced by the method of the present invention can be used in the following applications: protective bactericidal masks, filters for air conditioners for sterilising air supplied to clean rooms or operating rooms, bactericidal and virucidal plasters for external use, bactericidal underwear for soldiers and people engaged in extreme and dangerous activities, wound dressings, plasters and gauzes in surgery and therapy, for example, in the treatment of skin bums and wounds, purulent wounds, fistulas and bedsores, in surgical drapes and overalls for medical personnel, antimicrobial packaging of sterile instruments, medicines and pharmaceuticals, dosage forms coating, household wipes for the prevention of intestinal diseases, toilet paper, facial wipes etc. EXAMPLES

Example 1: Mercurisation of coton fabric or coton-fabric articles

[0034] Aqueous solutions of mercury chloride (HgCh) having concentrations from 0.1 M to 0.01 M are prepared in advance. In this example, the optional concentrations of two solutions are 0.1 M and 0.01 M. Also, 7-10% aqueous alkali solution (KOH in the present example) is prepared in advance.

[0035] Ashless filter paper is soaked in or wetted with the prepared aqueous solution of the mercury chloride (HgCh) and placed on the bottom of the glass bath in 2-3 layers. A cotton fabric is placed over the wet filter paper and pressed tightly. The resulting sample is irradiated with full-spectrum bright light from a high-pressure mercury lamp (power 1 kW) located at a height of 20-25 cm from the surface of the sample for 5-10 minutes. After that, the cotton fabric is immersed for 7-10 seconds in the prepared alkali solution heated to 70-80 °C, in which the cotton fabric becomes dark.

[0036] The final colour of the product and, accordingly, the mercury concentration in the carrier material depends on the concentration of the initial mercury solution, as well as the power of the luminous flux incident on the carrier material, the irradiation time and distance to the light source (mercury lamp in the present example). The last three parameters are combined in the following table in the "Total Irradiation Energy" column.

[0037] Finally, the coloured cotton fabric is intensively washed and rinsed with running water to remove all unreacted water-soluble and insoluble mercury compounds. After air drying, the sample of the bactericidal and antiviral cotton fabric is ready for use. The results of these experiments are presented in Table 1:

Table 1: Mercurisation of cotton fabric

[0038] To determine the bactericidal properties of the materials obtained, the microbiological analysis for the bactericidal activity of the mercurised cotton-fabric samples was carried out and evaluated by "HyLabs", certified by ISO and ISRAC and accredited by the Israeli Ministry of Health. [0039] HyLabs adhered to the following procedure for microbiological analysis. TSA plates were inoculated with 500 pl from Staphylococcus aureus ATCC 6538 and Pseudomonus aeruginosa ATCC 9027 10 5 6 CFU/ml suspension by spreading technique. In the middle of the plates, a 1 cm x 1 cm fabric was placed. The TSA plates were incubated at 30-35 °C for 24 hours. Done in duplicates. For positive control, the same procedure as above, but without the fabric was carried out. For negative control - the same procedure as above, but without the inoculation step. The results of this study are presented in Table 2:

Table 2: Bactericidal properties ofmercurised cotton fabric

[0040] As seen in above Table 2, all tested samples showed a very good bactericidal effect against bacteria Pseudomonus aeruginosa and Staphylococcus aureus. Of particular note is the excellent bactericidal effect of the tested materials against Pseudomonas aeruginosa, against which there are still no reliable drugs.

[0041] To determine the virucidal activity of the materials obtained, antiviral tests assessing virucidal activity of the mercurised cotton tissue samples against human coronavirus NL63 were carried out using protocol ISO 18184 by "Virology Research Services Ltd." (London, UK), certified by ISO/IEC 17025:2017 Accreditation No. 111376. The results of the study are presented in Table 3:

Table 3: The average infectious units per ml recovered from the test and reference control materials at a contact time of 2 hours with the NL63 coronavirus

[0042] As seen in above Table 3, under the conditions tested, samples of mercurised cotton fabric display virucidal activity against human coronavirus NL63 when using a contact time of 2 hours. The average recovered titre for the treated material was 791 TCID50/sample compared to the average recovered titre of 45,900 TCID50/sample for the reference control. The Mv value (antiviral activity) was 2.57. The average infectious units per ml recovered from the test and reference control at a contact time of 2 hours with the virus are shown in Table 4:

Table 4: The average infectious units per ml recovered from the test and reference control at a contact time of 2 hours with the virus

Example 2: Mercurisation of cellophane film

[0043] Aqueous solutions of mercury chloride (HgCh) and KOH are prepared as in Example 1. Ashless filter paper is soaked in or wetted with the prepared aqueous solution of mercury chloride and placed on the bottom of the glass bath in 2-3 layers. A cellophane film is placed over the wet filter paper and pressed tightly. The resulting sample is irradiated with the full-spectrum bright light mercury lamp (power 1 kW), fixated with the alkali solution, washed and dried as in Example 1. The final colour of the product and, accordingly, the mercury concentration in the carrier material depends on the concentration of the initial mercury solution, as well as the power of the luminous flux incident on the carrier material, the irradiation time and distance to the mercury lamp light source. The last three parameters are combined in the table in the "Total irradiation energy" column. The results of this experiment are presented in the Table 5:

Table 5: Mercurisation of cellophane film

[0044] Bactericidal properties of the mercurised cellophane film of the present example were tested by "HyLabs ". The test procedure was the same as in Example 1. The results of this study are presented in Table 6: Table 6: Bactericidal properties ofmercurised cellophane film

[0045] Tested samples showed a very good bactericidal effect against different bacteria, such as Pseudomonas aeruginosa, Staphylococcus aureus , Shigella flexneri, and Salmonella typhimurium. Of particular note is the excellent bactericidal effect of the tested materials against Pseudomonas aeruginosa, against which there are still no reliable drugs.

Example 3: Selective mercurisation and obtaining a bactericidal image on a carrier material [0046] Aqueous solutions of mercury chloride (HgCh) and KOH are prepared as in Example 1. Ashless filter paper is soaked in or wetted with the prepared aqueous solution of mercury chloride and placed on the bottom of the glass bath in 2-3 layers. A carrier material (cellophane film or cotton fabric) is placed over the wet filter paper and pressed tightly. A slotted template made of opaque synthetic material is applied over it. The resulting sample is irradiated with a bright light of a total spectrum mercury lamp (power IkW), fixated, washed and dried as in Example 1. The results of this experiment are presented in Table 7:

Table 7: Selective mercurisation of cellophane film and cotton fabric