RU2758770C1 - Method for obtaining vinyl wallpaper with a bactericidal coating - Google Patents

Abstract

FIELD: vinyl wall covering.

SUBSTANCE: invention can be used for disinfection of surfaces and air in the premises of medical institutions. The method for producing vinyl wallpaper with a bactericidal coating includes obtaining silver nanoparticles on a carbon matrix, making a biocidal suspension including silver nanoparticles, and applying the resulting suspension to the front surface of the wallpaper. Silver nanoparticles are obtained by spraying a composite graphite electrode including silver powder in a plasma of a DC electric arc discharge in an inert gas atmosphere.

EFFECT: invention provides high and long-lasting bactericidal activity of wallpaper in relation to strains of different classes of microorganisms.

5 cl, 4 dwg

Description

The invention relates to methods for producing wallpaper with a bactericidal coating, which prevents the formation of bacteria and fungi on the surfaces of the glued products and is also capable of independently removing pathogenic microorganisms from the room air and inhibiting the process of their reproduction. The invention can be used for disinfection of surfaces and air in rooms, especially in crowded places, in medical institutions.

One of the options for solving the problems of disinfecting surfaces and air in rooms, especially in crowded places, in medical institutions, can be pasting surfaces with wallpaper with a bactericidal coating based on water-dispersed paintwork materials (paints and varnishes) with nanosized particles of silver, copper or gold with increased biocidal activity, which prevent the formation of bacteria and fungi on surfaces, and are also able to independently remove pathogenic microorganisms from the air of the room and inhibit the process of their reproduction.

Known antibacterial wallpaper and a method of obtaining them [CN 110157344, 2019-08-23, C08K 13/02; C08K 3/04; C08K 3/08; C08K 3/22; C08K 3/34; C08K 5/12; C08K 5/523; C08L 61/06; C08L 69/00; C08L 87/00; C08L 97/02; C09J 11/04; C09J 163/00; C09J 7/29; C09J 7/30; E04F 13/00]. The surface layer of the wallpaper contains silver nanoparticles, which provide their bactericidal properties. The method for making wallpaper includes the following steps: 1) Preparing a mixture containing an antibacterial agent by mechanically mixing the components of the mixture; 2) heat treatment of the mixture; 3) extrusion molding.

In this solution, the minimum content of silver nanoparticles by weight is more than 0.3% (1: 300). In the proposed solution - 0.01%. In this solution, there is no information on how silver nanoparticles are synthesized and stored, there is no data on the size of silver nanoparticles, there is no quantitative information on the effectiveness of antibacterial action and on the duration of bactericidal properties.

Known antibacterial wallpaper and a method of obtaining them [CN 102660908, 2012-09-12, В32В 33/00; D21H 27/20; E04F 13/075]. Wallpaper contains a backing, a printed layer, and an antibacterial layer. The antibacterial layer is formed by an ink containing the following components in parts by weight: 100 parts of a water-based printing varnish and 0.1 parts to 2 parts of an antibacterial agent. The water-based ink for printing is selected from matt water-based printing varnish or water-based clear varnish for printing. The antibacterial agent is silver, and examples of implementation of the invention are given for inorganic complexes such as silver-zirconium-phosphate and water glass with embedded silver ions. The backing is any wood pulp paper, non-woven paper and fabric.

In this solution, the antibacterial agent is added to the water-based paint or varnish and mechanically mixed until a homogeneous suspension is obtained. This solution does not use silver nanoparticles, there is no information on the durability of the bactericidal properties. It is stated that the bactericidal activity of wallpaper exceeds 99.99% for Escherichia coli, Staphylococcus aureus and other types of bacteria, but there is no supporting experimental information.

The closest in terms of the totality of features is the invention of wallpaper with bactericidal properties [RU 2417281; 11/30/2009; D21H 27/20; D21H 21/36; D21H 19/36; C09J 7/04; C09D 5/14]. The general technology for the manufacture of wallpaper, according to the description of the specified invention, includes:

1) coating the wallpaper with a germicidal agent, for example, by rolling or spraying; 2) removal of the water contained in the varnish after coating by exposing the front side of the wallpaper, for example, to warm air. Antibacterial coating of wallpaper is performed by applying a suspension, the ratio of ingredients in which is: 95-99.99 wt. % varnish and 0.01-5 wt. % powder of a porous carbon support with silver nanoparticles 2-50 nm in size, obtained by mixing using ultrasound.

However, in the description of the invention there is no information about the details of the method of dispersion used, which is important for obtaining a suspension with a high degree of dispersion.

In this solution, it is mentioned that the powder of a porous carbon support with silver nanoparticles is obtained by high-temperature evaporation of a composite graphite-silver electrode by known methods with varying the operating parameters of the process. However, in the description of the invention there is no information about the details of the method used, which affects the quality of the obtained material.

In this solution, there is no quantitative information about the effectiveness of the antibacterial effect of coated wallpaper based on a suspension with a concentration of Ag-C nanopowder of 0.01-5 wt. %. There is also no information on the duration of the bactericidal properties of the coating. There is no such information, since no studies were carried out for any of the indicated concentrations of the suspension, on any of the microorganisms.

In addition, the specified invention is aimed at achieving another result, namely, the creation of wallpaper having a single-layer antibacterial coating of low-component composition and a simple manufacturing technology.

It should also be noted that prior art methods are known for producing metal-carbon nanocomposites.

A known method for the synthesis of metal nanoparticles by deposition on a porous carbon material [RU 2685564, 09.01.2018, B22F 9/12, C23C 14/30, B82Y 40/00]. In this solution, the synthesis of the material is carried out by depositing metal nanoparticles, including silver, on an already prepared carbon matrix. The method is carried out in two stages: synthesis of a carbon matrix; deposition of metal nanoparticles by sputtering with an electron beam in a vacuum chamber.

This method has a number of both technical drawbacks and drawbacks in the properties of the synthesized material.

Known methods for the synthesis of metal-carbon nanocomposites in the plasma of a DC arc discharge, for example, a method for the synthesis of nanostructured composite CeO ₂ - PdO material [RU 2532756, 01.07.2013, В82В 3/00, B01J 37/34, C01F 17/00, B01J 23 / 63, B01J 23/44], a method for the synthesis of a powder of superparamagnetic nanoparticles Fe ₂ O ₃ [RU 2597093, 25.06.2015, C01G 49/06, В82В 3/00, B82Y 30/00, B22F 9/14, B22F 9/16 , H01F 1/01].

These solutions use a two-step synthesis method. The first stage of synthesis: synthesis of a metal-carbon nanostructured material in an arc discharge by spraying a composite metal-graphite electrode in an inert gas. Second stage: annealing in an oxygen-containing atmosphere.

The difference lies in the use of a different metal with a different range of determining parameters (current, voltage, pressure, composition of the sprayed electrode), as well as the simplicity of the method (the number of stages).

It should also be noted that known from the prior art methods of dispersing metal nanoparticles in a liquid by ultrasound, for example:

A method of preparing an aqueous solution of a silver-carbon nanocomposite [TW 201804478; 2018-02-01; B01J 19/10; B22F 9/24; Н01В 1/02; Н01В 1/04; H01B 13/00; H01G 11/30], which includes two stages. At the first stage, a stable aqueous suspension based on carbon materials is created, stabilized with a sulfonate anionic surfactant. At the second stage, water droplets with dissolved silver salt are added to the suspension and treated with ultrasound.

The method is difficult to implement. Silver nanoparticles in a liquid are subject to coagulation, since they are not covered with a carbon matrix, therefore, their bactericidal activity decreases depending on the rate of their coagulation and their growth in size.

A method of synthesizing a magnetic fluid based on water and magnetic nanoparticles on a carbon matrix [RU 2635621; 12/18/2015; H01F 1/44; В82В 3/00; B82Y 40/00; B82Y 99/00], including stabilization of magnetic nanoparticles with a surfactant, separation and ultrasonic dispersion of the resulting solution. The invention makes it possible to synthesize a magnetic fluid resistant to the coagulation of magnetic particles.

In this solution, as one of the components of the dispersible solution, a powder of magnetic nanoparticles on a carbon matrix, obtained by the plasma-arc method by spraying an iron-graphite electrode with appropriate process parameters, is used. A surfactant (neonol) is used to create a stable aqueous suspension based on iron-carbon powder.

The specified method is similar to the stage of dispersing the silver-carbon nanopowder and the base fluid in the claimed invention in a number of ways:

• use powder of metal nanoparticles on a carbon matrix;

• powder obtained by plasma-arc method by spraying a composite metal-graphite electrode;

• dispersion is carried out by ultrasound;

• the resulting dispersion is defended and drained.

However, this method is intended to obtain a liquid with other components and for other purposes.

The proposed method includes, as steps, a number of methods known from the prior art, but at the same time a new result is achieved, namely, wallpaper with a bactericidal coating, which has a high and long-term bactericidal activity against strains of different classes of microorganisms.

The objective of the present invention is to provide a method for producing vinyl wall-paper with a bactericidal coating having a high and long-term bactericidal activity against strains of different classes of microorganisms that are pathogenic in relation to mammals and humans, and suitable for use in industrial and domestic premises, in children's and medical institutions, in crowded places, etc.

The problem is solved by the fact that a method is proposed for producing vinyl wallpaper with a bactericidal coating, which includes the following steps:

1.Production of an antibacterial agent, which is silver nanoparticles on a carbon matrix, by sputtering a DC electric arc discharge in an inert gas atmosphere at a pressure of 1-500 Torr, a discharge current of 100-300 A and a discharge voltage of 15-35 V of a composite electrode , which is a graphite rod, into the drilled cavity of which a mixture of silver and graphite powders with a silver content of 1 to 100 wt. %,

2. Obtaining a biocidal suspension by performing the following actions:

- introduction of silver nanoparticles on a carbon matrix into the base liquid, which is a water-dispersed paint and varnish material diluted with water to a conditional viscosity of no more than 35 seconds, so that the concentration of silver nanoparticles on a carbon matrix to the base liquid is from 1 to 5 wt. %,

- processing of the resulting composition in an ultrasonic bath with a power of 60-1200 W and a frequency of 15-40 kHz for 10-600 minutes with continuous stirring with a mixer with a rotation frequency of 1-20 Hz,

- settling for at least 4 hours,

- draining, preventing overflow of sediment,

- dilution with the base liquid so that the concentration of silver nanoparticles on the carbon matrix in the final product is from 0.1 to 0.01 wt. %,

3. application of the resulting biocidal suspension to the front surface of the wallpaper and heat treatment of the applied layer.

According to the invention, the inert gas, in the atmosphere of which silver nanoparticles are synthesized on a carbon matrix, is selected from the group: He, Ne, Ar, Kr, Xe.

According to the invention, the nanoparticles of silver on a carbon matrix synthesized by this method have sizes from 1 to 500 nm.

According to the invention, the water-dispersed paint and varnish material is selected from the group:

- transparent binder SI-WALL 794XXX series;

- binder for SI-WALL mother-of-pearl 794XXX series;

- glossy binder of the FTD 9XXX series - FOLCO® AQUAFLEX FTD 9XXX VERSCHNITT;

- glossy binder of the FSC 10-XXX series - FOLCO® AQUAFLEX FSC 10-XXX EFFEKTBINDEMITTEL;

- matt binder of the FSC 10-XXX series - FOLCO® AQUAFLEX FSC 10-XXX EFFEKTBINDEMITTEL;

- water-based printing ink for gravure printing of the 7.63XX series - Aquasafe GR GlitterInk Concentrate 7.63XX;

- water-based printing ink for gravure printing of the 7.64XX series - Aquasafe GR GlossInk Concentrate 7.64XX;

- water-based printing ink for screen printing series 80.50XX - Aquasafe R / S Glosslnk 80.50XX.

According to the invention, the obtained wallpaper with a bactericidal coating exhibit a bactericidal activity of 90% or more (for an exposure time of 60 minutes) for at least 3.4 years against microorganisms from the group: Candida ablicans; Staphylococcus aureus; Escherichia coli; Pseudomonas aeruginosa; Enterococcus faecalis; Staphylococcus epidermidis.

The resulting vinyl wallpaper is a material for lining walls and ceilings indoors, the basis of which is non-woven or paper, and the top layer is polyvinyl chloride, on top of which a coating with an antibacterial agent is applied to impart bactericidal properties to the wallpaper.

Silver nanoparticles with sizes of 1-500 nm on a carbon matrix (carbon porous carrier) are used as an antibacterial agent. The porous carbon support has a specific density of 0.03-0.1 g / cm ³ , a specific surface area of 50-200 m ² / g, and a pore size of 5-50 nm. The content of silver nanoparticles in the porous carbon support is 1-60 wt. %.

Silver nanoparticles on a carbon matrix are synthesized by spraying in the plasma of an electric arc discharge of a direct current in an atmosphere of an inert gas (He, Ne, Ar, Kr, Xe) of a composite electrode, which is a graphite rod with a drilled cavity filled with a mixture of silver and graphite powders, the silver content in which is from 1 to 100 wt. %. Sputtering of the composite electrode is carried out at a buffer gas pressure of 1-500 Torr, a discharge current of 100-300 A, and a discharge voltage of 15-35 V.

The chosen method for the synthesis of a silver-containing bactericidal nanopowder makes it possible to obtain silver nanoparticles, which are reliably held by a carbon matrix, preventing their coagulation and retaining their bactericidal activity. The stability of silver nanoparticles on a carbon matrix to coagulation of silver nanoparticles will allow their transportation and long-term storage in the form of a powder.

G.,

N.,

F., Martinez-Mendoza J., Ruiz F. Synthesis and antibacterial activity of silver nanoparticles with different sizes // J. Nanoparticle Res. - 2008. - V. 10, No 8. - P. 1343-1348].The chosen method for the synthesis of a silver-containing bactericidal nanopowder, in addition, makes it possible to control the size of the synthesized nanoparticles by varying the process parameters. It is known that the smaller the size of nanoparticles, the higher their bactericidal activity [

G.,

N.,

F., Martinez-Mendoza J., Ruiz F. Synthesis and antibacterial activity of silver nanoparticles with different sizes // J. Nanoparticle Res. - 2008. - V. 10, No 8. - P. 1343-1348].

The bactericidal activity of the obtained silver-containing nanopowder was investigated on strains of a number of microorganisms:

1. Candida ablicans - yeast-like fungi;

2. Staphylococcus aureus - Staphylococcus aureus;

3. Escherichia coli - Escherichia coli;

4. Pseudomonas aeruginosa - Pseudomonas aeruginosa;

5. Enterococcus faecalis - enterococci;

6. Staphylococcu sepidermidis - epidermal staphylococcus.

To study the bactericidal properties, 20 mg of the synthesized material was placed in a 20 ml container of nat. solution for 6 hours. The second container contained just physical. solution. The same amount of Staphylococcus aureus bacteria was added to both containers and kept for 6 hours. After that, samples from both containers were placed in a nutrient medium, in which bacteria multiplied. Each living bacterium formed a colony. After two weeks, these colonies were visible with the eye. The number of colonies is proportional to the original number of living bacteria. Therefore, the ratio of the number of living bacteria in the "control" experiment to the number of living bacteria that were in physical. solution with the synthesized material, characterizes the bactericidal properties of the synthesized nanopowder. FIG. Figures 1 and 2 show photographs of the number of colonies in these experiments.

FIG. 1 - control (without nanopowder).

FIG. 2 - decrease in the number of colonies after interaction with Ag-C nanopowder.

Counting the number of colonies showed that under the conditions of the present experiment, the presence of synthesized silver nanopowder on a carbon matrix led to the death of more than 99% of bacteria.

A biocidal suspension is obtained by dispersing a base liquid and a silver-containing bactericidal nanopowder (silver nanoparticles on a carbon matrix) using ultrasound.

As a base liquid, water-dispersive paints and varnishes (LKM) are used, diluted with water until the required viscosity is reached. The relative viscosity of the base liquid for the manufacture of a biocidal suspension, measured with a VZ-4 viscometer, should be no more than 35 seconds. If the viscosity is higher, the base fluid is diluted with water until the required viscosity is reached. An increase in viscosity above this value leads to a noticeable attenuation of ultrasonic waves, which leads to unsatisfactory dispersion of the silver-carbon material and a decrease in the biocidal efficiency of the suspension.

Paints and varnishes for use in a biocidal suspension are selected from the following list:

- transparent binder SI-WALL 794XXX series;

- binder for SI-WALL mother-of-pearl 794XXX series;

- glossy binder of the FTD 9XXX series - FOLCO® AQUAFLEX FTD 9XXX VERSCHNITT;

- glossy binder of the FSC 10-XXX series - FOLCO® AQUAFLEX FSC 10-XXX EFFEKTBINDEMITTEL;

- matt binder of the FSC 10-XXX series - FOLCO® AQUAFLEX FSC 10-XXX EFFEKTBINDEMITTEL;

- water-based printing ink for gravure printing of the 7.63XX series - Aquasafe GR GlitterInk Concentrate 7.63XX;

- water-based printing ink for gravure printing of the 7.64XX series - Aquasafe GR Glosslnk Concentrate 7.64XX;

- water-based printing ink for screen printing series 80.50XX - Aquasafe R / S Glosslnk 80.50XX.

Each of the above paints and varnishes has a safety data sheet in accordance with Regulation (EC) No 1907/2006 (REACH) and amended by Regulation (EU) 2015/830.

Silver nanoparticles on a carbon matrix are introduced into the base liquid so that the concentration of silver nanoparticles on the carbon matrix to the base liquid is from 1 to 5 wt. %. Then, the resulting composition is dispersed by ultrasound.

The use of ultrasound makes it possible to obtain a monodisperse suspension. The homogeneity and high degree of dispersion provides a higher bioavailability of silver nanoparticles. In addition, suspensions obtained using ultrasound are more stable during storage than those obtained by mechanical dispersion.

Received a biocidal suspension as follows.

A bactericidal nanopowder was poured into a heat-resistant glass beaker, into which the base liquid was poured, while the bactericidal nanopowder was one part, and the base liquid was 10 parts. The glass was placed in an ultrasonic bath with a power of 60-1200 W and a frequency of 15-40 kHz. Ultrasonic treatment was carried out for 10-600 minutes with continuous stirring with a stirrer with a rotation frequency of 1-20 Hz. The resulting suspension was defended for at least 4 hours. After that, the resulting suspension was poured into a clean sealed vessel, preventing the overflow of sediment, which in a small amount dropped out at the bottom of the glass.

For application to wallpaper, the resulting suspension was diluted with a base liquid so that the concentration of the bactericidal nanopowder in the final product (biocidal suspension) was from 0.1 to 0.01 wt. %.

Such a biocidal suspension is suitable for application to wallpaper with giving them bactericidal properties, makes it possible to create on the surface of the wallpaper a durable transparent polymer film containing silver nanoparticles, which serve as a bactericidal agent that decontaminates the air in the room. The suspension is suitable for application to any type of wallpaper: vinyl, paper, textile, non-woven.

After applying the slurry to the front surface of the vinyl wallpaper, the coating is heat treated, which removes water and polymerizes the varnish component. The covering of the wallpaper is an elastic polymer film, which gives the wallpaper bactericidal properties without affecting the color and appearance of the wallpaper. The coating is chemically inert and environmentally friendly.

The bactericidal properties of vinyl wall coverings with a coating based on silver nanoparticles on a carbon matrix were investigated for wallpaper samples, both made and after artificial aging, which meets the requirements of Rospotrebnadzor and corresponds to a certain durability of bactericidal properties.

The accelerated aging process was carried out in accordance with GOST 9.401-2018 “Unified system of protection against corrosion and aging (ESZKS). Paint and varnish coatings. General requirements and methods of accelerated tests for resistance to climatic factors ". The service life is calculated on the basis of clause 6.5.9 "Calculation of the estimated service life" GOST 9.401-2018.

When tested for bactericidal activity, bacteria were applied to the surface of the wallpaper. At the same time, the number of remaining living bacteria was monitored after a certain time.

1. Evaluation of the bacterial activity of vinyl wallpaper coated with silver nanoparticles on a carbon matrix.

Materials:

1) test strain Staphylococcus aureus ATCC25923;

2) wallpaper samples:

• coated with a suspension containing 0.1 wt. % carbon-silver material (denoted in Fig. 3 as 100%),

• coated with a suspension containing 0.05% wt. % carbon-silver material (denoted in Fig. 3 as 50%),

• a control sample coated with a suspension without a bactericidal component.

Method for assessing bactericidal activity

The S. aureus strain was stored in a liquid salt-free LB medium with 25% glycerol at -70 ° C. Before use, the cultures were plated on LB agar medium (Difco, USA) and incubated at 37 ° C for one day. Next, LB liquid nutrient medium was inoculated to obtain an overnight broth culture. To assess the bactericidal activity of the wallpaper, wallpaper samples with an area of 4 cm ^{2 were used} , on which 25 μl of a suspension culture containing 1 × 10 ⁵ CFU of S. aureus was applied. The suspension was evenly spread with a spatula over the silver-treated wallpaper surface and incubated at room temperature. The exposure time was 0, 30, and 60 minutes. Then each sample was placed in 10 ml of saline and mixed, then successive tenfold dilutions of the suspension were prepared and plated on agar LB medium. Petri dishes were incubated at 37 ° C for a day and the number of grown colonies was counted. The experiment was repeated twice, each time in three technical repetitions.

The bactericidal efficacy of the coating was evaluated by calculating the percentage of surviving cells using the formula: (Number of colonies on a coated sample / Number of colonies on a control sample) × 100%. The data from all experiments were averaged.

results

FIG. 3 shows the percentage of surviving cells (colonies) on experimental samples depending on the exposure time, where 1 - (marked in blue) a sample containing 0.05% by weight of carbon-silver material (indicated in FIG. 3 as 50%), 2 - (marked in red) a sample containing 0.1% by weight of carbon-silver material (indicated in FIG. 3 as 100%).

It was found that both versions of the coating have a bactericidal effect, but this effect is more pronounced in the sample with 100% coverage. For wallpaper with 50% coverage, the bactericidal effect did not differ statistically significantly at exposure times of 30 and 60 minutes. For wallpapers with 100% coverage, increasing the exposure time from 30 to 60 minutes significantly increased the bactericidal effect: the percentage of surviving cells decreased from 15% to 8%.

Conclusion

Experimental samples of wallpaper coated with silver nanoparticles have a bactericidal effect when bacteria are exposed on the surface of the wallpaper for 60 minutes:

1. 100% coverage (0.1 wt.% Bactericidal powder in suspension) ensures the death of more than 90% of S. aureus cells (decrease in the number of viable bacteria by 12.5 times);

2. 50% coating (0.05 wt.% Bactericidal powder in suspension) ensures the death of more than 65% of S. aureus cells (reducing the number of viable bacteria by 3 times).

2. Evaluation of the bacterial activity of artificially aged vinyl wallpaper coated with silver nanoparticles on a carbon matrix.

Materials:

1) test strain Staphylococcus aureus ATCC 25923

2) wallpaper samples:

• artificially aged wallpaper "OldAg" with a coating containing silver nanoparticles,

• uncoated control sample. Method for assessing bactericidal activity.

The S. aureus strain was stored in a liquid salt-free LB medium with 25% glycerol at -70 ° C. Before use, the cultures were plated on LB agar medium (Difco, USA) and incubated at 37 ° C for one day. Next, LB liquid nutrient medium was inoculated to obtain an overnight broth culture. To assess the bactericidal activity of the wallpaper, wallpaper samples with an area of 4 cm ^{2 were used} , on which 25 μl of a suspension culture containing 1 × 10 ⁵ CFU of S. aureus was applied. The suspension was evenly spread with a spatula over the silver-treated wallpaper surface and incubated at room temperature. The exposure time was 30 and 60 min. Then each sample was placed in 10 ml of physiological solution (0.9% NaCl) and kept under constant stirring to wash the deposited cells into the solution. Sequential tenfold dilutions of the resulting cell suspension were plated on agar LB medium and incubated at 37 ° C for a day, after which the number of grown colonies was counted.

The experiment was repeated twice, performing from three to six technical repetitions in each series of experiments.

FIG. 4 shows the results, namely, the number of living cells after exposure for 30 and 60 minutes, depending on the type of coating.

The results show that the test sample "OldAg" showed the highest bactericidal activity after 60 minutes exposure, which provided more than 90% cell death relative to the control wallpaper sample (uncoated). Artificial aging of the OldAg wallpaper sample with applied silver nanoparticles, simulating their storage, did not worsen its bactericidal properties.

Exposure for 30 minutes did not have a statistically significant effect on the bactericidal properties of the samples.

Conclusion

Experimental samples of "OldAg" wallpaper coated with silver nanoparticles have a bactericidal effect when bacteria are exposed on the surface of the wallpaper for 60 minutes: this sample of wallpaper, after exposure to simulating aging of the sample, ensured the death of 91% of S. aureus cells applied to the surface (a decrease in the number viable bacteria 11 times), that is, the bactericidal properties did not deteriorate.

Based on the studies carried out and the calculation of the service life on the basis of clause 6.5.9 "Calculation of the estimated service life" GOST 9.401-2018, the bactericidal activity of the wallpaper coating is maintained for at least 3.4 years.

Thus, the vinyl wallpaper obtained by the proposed method has a high, 90% or more, and long-term, at least 3, 4 years, bactericidal activity against pathogenic microorganisms, and can be recommended for use in places of large concentrations of people, including in children's and medical institutions, in industrial and domestic premises, etc.

Claims (13)

1. A method of obtaining vinyl wall-paper with a bactericidal coating, including: - obtaining an antibacterial agent, which is silver nanoparticles on a carbon matrix, by high-temperature evaporation of a composite electrode, - obtaining a biocidal suspension by mixing under the influence of ultrasonic vibrations of a water-dispersed paint and varnish material and an antibacterial agent, - applying the resulting biocidal suspension to the front surface of the wallpaper and drying the applied layer, characterized in that the preparation of an antibacterial agent, silver nanoparticles on a carbon matrix, is carried out by spraying a DC electric arc discharge in an inert gas atmosphere at a pressure of 1-500 torr, a discharge current of 100-300 A and a discharge voltage of 15-35 V of a composite electrode, which is a graphite rod, into the drilled cavity of which a mixture of silver and graphite powders with a silver content of 1 to 100 wt.% is pressed, the biocidal suspension is obtained by performing the following actions: - introduction of silver nanoparticles on a carbon matrix into the base liquid, which is a water-dispersed paint and varnish material diluted with water to a conditional viscosity of no more than 35 seconds, so that the concentration of silver nanoparticles on a carbon matrix to the base liquid is from 1 to 5 wt .%, - processing of the resulting composition in an ultrasonic bath with a power of 60-1200 W and a frequency of 15-40 KHz for 10-600 minutes with continuous stirring with a mixer with a rotation frequency of 1-20 Hz, - settling for at least 4 hours, - draining, preventing overflow of sediment, - dilution with the base liquid so that the concentration of silver nanoparticles on the carbon matrix in the suspension is from 0.1 to 0.01 wt%. 2. A method for producing vinyl wallpaper with a bactericidal coating according to claim 1, characterized in that the inert gas, in the atmosphere of which silver nanoparticles are synthesized on a carbon matrix, is selected from the group: He, Ne, Ar, Kr, Xe. 3. The method according to claim 1, characterized in that the silver nanoparticles on the carbon matrix have sizes from 1 to 500 nm. 4. The method according to claim 1, characterized in that the resulting wallpaper exhibit a bactericidal activity of 90% or more for at least 3, 4 years against microorganisms from the group: Candida ablicans; Staphylococcus aureus; Escherichia coli; Pseudomonas aeruginosa; Enterococcus faecalis; Staphylococcus epidermidis.

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