IT202100017894A1 - Antibacterial and antiviral treatment for coins, banknotes and tokens - Google Patents

Description

?Antibacterial and antiviral treatment for coins,

banknotes and tokens?

Technical field of the invention

The present invention finds application in the field of coins, paper money and tokens.

State of art

In this particular historical moment, the advent of COVID 19 has stimulated the development of means for cleaning, sanitizing, sanitizing, disinfecting surfaces and objects in order to make them uncontaminated by bacterial and viral loads. In this case, banknotes and coins were found to be a means of transmission of the SARS-Cov-2 virus (COVID-19) because, given the porous nature of the substrate, it is verified, through studies conducted, the survival of up to 28 days on surfaces such as banknotes and 3-4 days on metal and plastic, i.e. on coins and tokens. Therefore, using banknotes, coins and tokens constitutes a serious risk of the transmission of the virus among the population. In a single day the circulation of banknotes, coins and tokens and you can? hypothesize how the virus can be transmitted from person to person in a very short time. The resistance of viruses in the environment ? relatively low, even if some viruses (for example some respiratory viruses just like coronaviruses) can survive longer? for a long time, depending on the local environmental conditions and the type of substrate on which they are deposited. Analysis of 22 studies reveals that human coronaviruses such as severe acute respiratory syndrome coronavirus (SARS), Middle East respiratory syndrome coronavirus (MERS), or endemic human coronaviruses (HCoV) can persist on inanimate surfaces such as paper, fabrics , metal, glass or plastic up to 9 days, but can be effectively inactivated by surface disinfection procedures with specific products. According to a study conducted by? University? of Oxford, a European banknote contains an average of 26,000 bacteria, belonging to different species, some of which are pathogenic. The most contaminated ? the Danish krone (40,200 bacteria), followed by the Swiss franc (32,400 bacteria). The euro card instead? the "P? clean, with an average of 11,000 microorganisms present. This data ? of 2014, well before the advent of COVID 19. In a research more? recently dated 2020, researchers from New York University analyzed the presence of microorganisms on dollar bills. The study is part of the ?Dirty Money? project, which aims to reconstruct the state of health of citizens by analyzing the variety of of bacteria from the DNA of the microbes on the money in circulation, by sequencing the DNA present. Did the researchers succeed in this? to identify on paper money a great diversity? of bacteria, most relatively harmless to people, but some potentially dangerous. In total, more than 3,000 types of bacteria have been identified, including some drug-resistant species; only about 20% of bacterial DNA ? found to belong to known species, while for the rest they are micro-bacteriological charges not yet classified. The species most Abundant identified on paper money are the bacteria that cause acne, followed by the bacterial flora normally present on the skin. But ? The presence of pathogenic staphylococcal species and bacteria associated with gastric ulcer, pneumonia and food poisoning has also been found. From the moment in which thousands of bacteria, fungi and pathogens lurk on a banknote, it is clear that it can cause diseases such as skin infections, stomach ulcers, food poisoning, etc.

Summary of the invention

The inventors of the present patent application have surprisingly found that the above problems can be solved by the solution of the present invention, which provides permanent products, i.e. products which last over time once applied to a substrate, capable of eliminating said microorganisms such as bacteria and viruses, with functional chemical additives, capable of activating themselves even with a photochemical action, suitable for food contact, as well as? the methods to obtain them.

Object of the invention

In a first object, the present invention describes a solution for the antibacterial and antiviral treatment of coins, banknotes, tokens and the like.

In a second object, ? described a method for the preparation of the antibacterial and antiviral solution of the invention.

In a third object, ? described a method for the antibacterial and antiviral treatment of coins, banknotes, tokens and the like.

Coins, banknotes, tokens and the like treated according to the invention represent further objects of the present patent application.

Brief description of the figures

Figure 1 shows the industrial plant for the preparation of the solutions of the present invention; Figure 2 shows a plant for applying the solutions of the present invention onto banknotes with flexographic printing;

Figure 3 shows a plant for applying the solutions of the present invention to coins and tokens;

Figure 4 shows a graph with the results of the tests on the activity? photocatalytic;

Figure 5 shows the results obtained from the analysis of SARS-Cov-2 viral strains according to ISO 18184:2019.

Detailed description of the invention

Detailed description of the invention

Titanium dioxide

Titanium dioxide? a semiconductor material with a crystalline structure, having a valence band separated from a conduction band by a given energy difference.

Like most materials, titanium dioxide when struck by electromagnetic radiation absorbs energy from the radiation. When is the absorbed energy? greater than the energy difference between the valence band and the conduction band, an electron is promoted from the valence band to the conduction band, generating an excess of electronic charge (e-) in the conduction band and an electron hole (h+) in the valence band. Titanium dioxide? in the solid state at room temperature in crystalline form such as anatase, rutile or brookite. The anatase ? the most active crystalline form from the photocatalytic point of view and has an energy difference between the valence band and the conduction band of 3.2 eV. It follows that, if this material is irradiated with photons having an energy greater than 3.2 eV, ie? with electromagnetic radiation of wavelength from 380 nm to 420 nm, an electron is promoted from the valence band to the conduction band. There? happens in particular when the titanium dioxide ? affected by ultraviolet radiation (UV), for example emitted by an ultraviolet lamp, or by solar radiation. Electronic holes can oxidize most organic compounds. Such electronic holes can, for example, react with a water molecule (H2O) generating a hydroxyl radical (?OH) which ? highly responsive. The excess electrons have a very high reducing power and can react with the oxygen molecule to form the superoxide anion (O2?-).

The oxidation reaction of the water molecule? shown in the diagram (?) and the reduction reaction of? oxygen ? shown in the diagram (??):

TiO2(h+) H2O? TiO2 ?OH H<+>; (?)

TiO2(e-) O2? TiO2 O2?- (??)

The hydroxyl radical (?OH) ? particularly active both for the oxidation of organic substances, for example present in the air, and for the inactivation of microorganisms, which for example can be harmful to humans.

In particular, organic compounds are oxidized to carbon dioxide (CO2) and water (H2O), nitrogen compounds are oxidized to nitrate ions (NO3-), sulfur compounds to sulphate ions (SO4<2->). Titanium dioxide? also capable of decomposing many gases or harmful substances, such as thiols or mercaptans, formaldehyde, ammonia, having an unpleasant odor. The decomposition of these gases or substances eliminates the bad odors associated with them.

The different behavior of rutile titanium dioxide compared to anatase titanium dioxide? due to the different quantity? of energy necessary for the excitation of an electron from the valence band to the conduction band of these two forms: 388 nm for anatase and 413 nm for rutile, and by the different reducing/oxidizing power, respectively of the excited electron and of the electronic gap generated, that ? high for anatase and low for rutile.

In accordance with a first object of the invention, ? described a solution to activities? antibacterial and antiviral.

For the purposes of the present invention, with the term ?activity? antibacterial? do you mean the property? of a solution according to the present invention to be effective against a broad spectrum of bacteria; this activity? ? tested in UNI ISO analyzes with Escherichia coli (Gram negative) and Staphylococcus aureus (Gram positive).

For the purposes of the present invention, with the term ?activity? antimicrobial? do you mean the property? of a solution according to the present invention to be effective against bacteria, mold and fungi and to continuously inhibit the growth of microorganisms on surfaces for very long periods of time.

For the purposes of the present invention, with the term ?activity? antiviral? do you mean the property? of a solution according to the present invention to be effective against viruses, such as, for example, COVID-19 and H1N1 (Influenza A), determined by a test according to ISO standards.

For purposes of the present invention, the solution comprises titanium dioxide and one or more? mixed additives.

The solution of the invention can be an aqueous solution or an alcoholic solution, in particular based on ethanol.

Alternatively, the solution of the invention can be a water/alcohol solution.

For the purposes of the present invention, titanium dioxide is represented by amorphous photocatalytic titanium dioxide.

In one aspect of the invention, the amorphous photocatalytic titanium dioxide is in colloidal form.

Pi? in particular, titanium dioxide ? included in the solution of the invention in a quantity? by about 0.01-30% (w/w).

Preferably, titanium dioxide ? included in the solution of the invention in a quantity? about 0.5%-3% (w/w), preferably about 0.9-1.2 (w/w) and more? preferably about 0.99% (w/w).

The rest of the solution? represented by water, a mixture of water/alcohol, in particular ethanol) and additives.

For the purposes of the present invention, water is preferably osmotic water or distilled water or purified water.

For the purposes of the present invention, such additives can be selected from the group comprising: powdered titanium dioxide. In particular, this can be represented by:

- powdered titanium dioxide of the Anastasio type

- powdered titanium dioxide of the Rutile type

- powdered titanium dioxide of the Brookite type.

Other additives can be selected from the group comprising:

- silver; alternatively, silver can? be for example in the form chosen from: silver chloride, silver nitrate, silver acetate, silver phosphate glass (or silver borophosphate glass or silver phosphoborate glass), silver zeolite, copper zeolite silver, silver sodium hydrogen zirconium phosphate, silver zinc zeolite;

- copper; alternatively, copper can? be, for example, in the form selected from: Bis(1-hydroxy-1H-pyridine-2-thionato-O,S)copper (pyrithione copper), Bis(N-cyclohexyl-diazenium-dioxy)-copper, copper hydroxide, oxide copper(I), copper(II) oxide, copper sulfate pentahydrate, copper thiocyanate, copper(II) carbonate-copper(II) hydroxide (1:1), copper powder, copper granules.

- soccer; football can be, for example, in the form chosen from: calcium oxide, calcium and magnesium oxide, calcium hydroxide, calcium dihydroxide, caustic lime, hydrated lime, slaked lime, lime, burnt lime, dolomitic lime, Quicklime.

Other additives can be represented by: Bronopol, salicylic acid, zinc, zinc pyrithione, calcium and magnesium oxide, chlorine dioxide (for example generated by acidification of sodium chlorite).

In accordance with a second object, ? described a process for the preparation of the solutions of the invention.

In particular, this process includes the phases of:

I) add water to amorphous photocatalytic titanium dioxide or to an alcoholic solution of amorphous photocatalytic titanium dioxide,

II) add to the solution obtained from phase I) one or more? additives.

According to one aspect of the present invention, in phase I) the titanium dioxide is included in the aqueous solution or in the alcoholic solution in a quantity? about 0.5%-3%, preferably about 0.9-1.2 (w/w) and more? preferably about 0.99% (w/w).

In particular, the alcoholic solution of titanium dioxide ? a 1-99% v/v aqueous solution of ethanol having an alcohol concentration of 60-99.9% v/v.

As regards phase II), the additives can be added in a quantity? by weight of about 0.0001-5%.

As regards some specific additives, these are preferably included in the following quantities:

- 0.5% silver on phosphate glass and/or

- 0.1% silver chloride and/or

- 0.001% silver acetate.

To obtain a homogeneous preparation, the emulsification is carried out by means of mechanical stirring at about 11,500 RPM for about 30 minutes.

For the industrial production of the solutions of the invention can? be used a system like the one shown in Figure 1.

For the preparations of the amorphous photocatalytic solutions of the invention ? It is possible to use an industrial plant completely in stainless steel SS316L, explosion-proof, composed of a hermetically closed container 101, capable of containing 150 liters of solution. The titanium dioxide is fed through the tank 102 by gravity. All ingredients are pre-weighed and prepared, so as indicated in the preparations of the photocatalytic solutions described above.

Stirring motor 103 is put into operation, ? a homogenizer with 2.2 kW of power, which spins at 2,800 RPM. From the tank 104 the titanium dioxide is introduced and homogenised for 30 minutes. From the previously emptied tank 102, the additives are introduced and stirred for another 30 minutes. The solutions are made and, through the pump 105, by opening the three-way valve 106, they are transferred into the drums through the outlet 107.

In accordance with a third object of the invention, ? described a method for the antibacterial and antiviral treatment of coins, banknotes and tokens which comprises the use of the solutions described above.

For the purposes of the present invention, this method is in particular described with reference to coins, paper money (banknotes) and tokens, where the method ? equally applicable to a number of similar products.

For example, the method pu? be equally applied to certificates, watermarked paper, checks and stamps, stamps, tax bands, passport paper, visa paper, event tickets (concerts, theater performances, exhibitions), meal voucher paper (such as the well-known ticket restaurants) , certificates of educational qualifications, etc.

In particular, such notes consist of sheets of at least 80% cotton fiber and, in one aspect of the present invention, 100% cotton fiber.

For the purposes of the present invention, the application of a solution of the invention to coins, banknotes, tokens or the like can be carried out using appropriate techniques, chosen for example from: spray application, flexographic printing, immersion.

In particular, the application on banknotes and paper money, cheques, watermarked paper and ?paper? ? preferably carried out by spray application or flexographic printing, while the application on coins, tokens and the like? conducted preferably by spray.

In particular, a solution of the invention can be applied in a quantity? approximately 1 g/m<2>, 2 g/m<2>, 3 g/m<2>, 4 g/m<2>, 5 g/m<2>, 6 g/m<2>, 7 g/m<2>, 8 g/m<2>, 9 g/m<2>, 10 g/m<2>, 11 g/m<2>, 12 g/m<2>, 13 g /m<2>, 14 g/m<2>, 15 g/m<2>, 16 g/m<2>, 17 g/m<2>, 18 g/m<2>, 19 g/m <2 >and 20 g/m<2>.

In one aspect of the invention, a solution according to what is described above is applied in a quantity? of about 5-15 g/m<2>, preferably of 6 g/m<2>,

After l?application pu? a drying phase must be provided, at room temperature or by heating, for example with jets of hot air, flame systems or resistance systems.

The application with flexographic printing on banknotes can? for example, be conducted using the system shown in Figure 2.

Banknotes are coated after being printed.

A further printing module (200) is provided, consisting of an anilox printing cylinder (201) which, partially immersed in the tank (202), transfers the antibacterial and antiviral solution to the printing plate (203). A back pressure cylinder (204) allows to generate a pressure such as to allow the solution to be applied to the printing sheet (210).

On the back side of the anilox print cylinder (201) ? installed a doctor blade (205) which serves to eliminate and/or clean the excess solution after depositing it on the printing sheet (210).

The anilox rolls (201) are made of ceramic and/or Teflon, and/or polymeric and/or other materials, they are engraved with different methods and the quality? of print is defined by lines/cm. Pi? the lines/cm are greater, the lower it will be? the quantity? of solution cm<3>/m<2 > transferred to the printing sheet (210) or more? the lines/cm are smaller, the greater it will be? the quantity? of solution cm<3>/m<2 > transferred to the printing sheet (210).

Anilox rolls (201) will therefore be used which, through the printing plate (203) will be able to transfer on the printing sheet (210) from 0.1 cm<3>/m<2 > to 30 cm3/m2 the solution preferably anilox rolls (201) will be used which, through the printing plate (203) will be able to transfer on the printing sheet (210) from 5 cm<3>/m<2 > to 8 cm3/m<2> . The directions of movement of the press sheet (210) are represented by arrows (250).

The directions of movement of the cylinders (201), (203) and (204) are represented by arrows (252).

The press sheet (210) will have to? be printed on both sides, i.e. on both the front side (211) and the back side (212).

? is it possible to insert a machine (300) that turns the print sheet (210) down? printed on one side (211) and uses an additional printing module (200) to print on the opposite side (212), or can? be flipped manually. The arrows (301) indicate that the press sheet (210) is been turned over by the machinery (300).

The power supply of the printing module (200) can? be single sheet (210), and/or multisheet (220), and/or reel (230), and all (210), (220) and (230), in both manual and automatic operation.

As regards the application of a solution according to the invention to coins or tokens, it can be used a system like the one shown in Figure 3.

To apply the solution of the invention, the coins and tokens (400) are inserted into a containment hopper (410), which automatically, through a photocell (420), feeds a vibrating system also with screw feeder (411), to then be disposed neatly on a conveyor belt (412). The coins and tokens (400) enter the machine (450) which ? equipped with one or more nozzles (460) for spraying the solution directly onto the upper side (401) of said coins and tokens (400). The nozzle or nozzles (460) can be fixed or they can be self-propelled or move horizontally with respect to the vertical feed direction of the conveyor belt (412). The arrows (430) indicate the direction of movement of the coins and tokens (400). Once the coins and tokens (400) come out of the machine (450), they are turned over on the side opposite to (401), or where the solutions have not yet been applied (402). An additional machine (450) always equipped with one or more? nozzles (460), apply solution to the opposite side (402). Hot air jets and/or flame systems and/or resistance systems (470) dry the coins or tokens (400).

An alternative to machinery (450) ? the machinery (490), mainly consisting of a stainless steel revolving drum (491). Inside said drum, are inserted one or more? nozzles (460) for spraying the solution directly onto said coins and tokens. The nozzles (460) are preferably stationary (461). The cylinder (491) inside? equipped with specific grooves (492) to turn the coins or tokens (400) and at the same time mix the solution directly on said coins and tokens (400) for a better application. At the end of this operation, ? it is advisable to use jets of hot air and/or flame systems and/or resistance systems (470) to dry the coins or tokens (400).

According to an alternative aspect of the present invention, the solutions described can be used for the preparation of the special paper used for printing banknotes.

Coins, banknotes, tokens and the like treated according to the invention represent further objects of the present patent application.

EXAMPLE 1

Preparation of 1 liter of solution:

Alcoholic Base

Using a percentage of additives preferably of 5 g per 1 liter of solution to be made, 474 ml is added to a beaker. of purified water to which is added a quantity? of Silver on phosphate glass (CAS 308069-39-8) having density? of 2.4 g/cm<3>, average particle size from 5 micron to 50 micron, in which the percentage of only Ag ? equal to about 2%. The prepared ingredients are dispersed in the beaker with the H2O on a magnetic stirrer at about 6,000 RPM, the operation lasts about 20 minutes. Subsequently the mixture is homogenized at 12,000-15,000 RPM with a shear emulsifier for about 20 minutes. Yet another process which consists in the sonication of the previously obtained compound using a 600 Watt Misonix 3000 for 10 minutes. If you want to create solutions greater in quantities?, the sonicator? equipped with Flocells?, capable of continuously processing up to 20 l/min of solution.

The resulting mixture is placed in a 1-litre separating funnel, dripped by gravity. slowly, in a funnel equipped with a paper filter for 1300/80 separations. The filtrate is collected in a flask. If the solutions to be filtered are too dense and/or concentrated for gravity filtration, you can? intervene using vacuum and/or reduced pressure filtration. In this case the flask for filtering has a lateral tail open on the upper side which, through a rigid tube, can be connected to a vacuum pump. On the top? of the flask, a neoprene gasket is placed, and a Buchner funnel is placed, the bottom of which is covered with filter paper for 1300/80 separations. By then activating the vacuum pump, the solution is sucked up, precipitates to the bottom of the flask and is separated from the solid material. To eliminate the impurities of the solution, and not clog the? plant, you can? to use Celite? 545 which has the average particle size from 0.02mm to 0.1mm. The pores of the paper are therefore not clogged and the holes more? free allow very fine particles to pass unhindered. Of the solution obtained you measure the quantity? of Ag through atomic absorption which must be between 0.01 mg/l and 20 g/l, preferably 100 mg/l. The additive solution is prepared.

In another beaker we added 414 mL of 96% CAS 64-17-5 ethanol and stirred magnetically at 6,000 RPM.

In a 1 liter separating funnel, we dripped by gravity the slowly 112 ml of a photocatalytic titanium dioxide solution (TiO2) whose active ingredient is Ti content, determined through atomic absorption according to EPA 6010D:2018 ? of 4.499 mg/Kg and stirred for 30 minutes.

Subsequently, always in the same 1 liter separating funnel, we dripped by gravity? slowly 474 ml of previously prepared additive containing 100 mg/kg of Ag and stirred for 30 minutes. After magnetic stirring, the mixture is emulsified at 11,500 RPM for 30 minutes. Is it obtained like this? a first solution of the invention.

EXAMPLE 2

Preparation of 1 liter of solution:

Water based

Using a percentage of additives preferably of 5 g per 1 liter of solution to be made, 474 ml of purified water is added to a beaker to which is added a quantity of Silver on phosphate glass (CAS 308069-39-8) having density? of 2.4 g/cm<3>, average particle size from 5 micron to 50 micron, in which the percentage of Ag ? equal to about 2%. The prepared ingredients are dispersed in the beaker with the H2O on a magnetic stirrer at about 6,000 RPM, the operation lasts about 20 minutes. Subsequently the mixture is homogenized at 12.00015.000 RPM with a shear emulsifier for about 20 minutes. Yet another process which consists in the sonication of the previously obtained compound using a 600 Watt Misonix 3000 for 10 minutes. If you want to create solutions greater in quantities?, the sonicator? equipped with Flocells?, capable of continuously processing up to 20 l/min of solution.

The resulting mixture is placed in a 1-litre separating funnel, dripped by gravity. slowly, in a funnel equipped with a paper filter for 1300/80 separations. The filtrate is collected in a flask. If the solutions to be filtered are too dense and/or concentrated for gravity filtration, you can? intervene using vacuum and/or reduced pressure filtration. In this case the flask for filtering has a lateral tail open on the upper side which, through a rigid tube, can be connected to a vacuum pump. On the top? of the flask, a neoprene gasket is placed, and a Buchner funnel is placed, the bottom of which is covered with filter paper for 1300/80 separations. By then activating the vacuum pump, the solution is sucked up, precipitates to the bottom of the flask and is separated from the solid material. To eliminate the impurities of the solution, and not clog the? plant, you can? to use Celite? 545 which has the average particle size from 0.02mm to 0.1mm. The pores of the paper are therefore not clogged and the holes more? free allow very fine particles to pass unhindered. Of the solution obtained you measure the quantity? of Ag through atomic absorption which must be between 0.01 mg/l and 20 g/l, preferably 100 mg/l. The additive is prepared.

In a second beaker we added 414 ml of purified water CAS 7732-18-5 and stirred magnetically at 6,000 RPM. In a 1 liter separating funnel, we slowly dripped by gravity, always in the second beaker, 112 ml of a solution of photocatalytic titanium dioxide (TiO2) whose active principle is Ti content, determined through absorption atomic according to EPA 6010D:2018 ? of 4.499 mg/Kg and stirred for 30 minutes. Subsequently, always in the same 1 liter separating funnel, we dripped by gravity? slowly 474 ml of previously prepared additive containing 100 mg/kg of Ag and stirred for 30 minutes. After magnetic stirring, the mixture is emulsified at 11,500 RPM for 30 minutes. A second solution according to the invention? what? prepared.

EXAMPLE 3

Preparation of 1 liter of solution:

Water based

Using a percentage of additives preferably of 0.01 g per 1 liter of solution to be made, 474 ml of purified water is added to a beaker to which is added a quantity of Silver Acetate 99.99% (CAS 563-63-3) having density? of 166.91 g/mol, traces of heavy metals present ?150 PPM, powder. The prepared ingredients are dispersed in the beaker with the H2O on a magnetic stirrer at about 6,000 RPM, the operation lasts about 60 minutes. Subsequently the mixture is homogenized at 12,000-15,000 RPM with a shear emulsifier for about 30 minutes. Yet another process which consists in the sonication of the previously obtained compound using a 600 Watt Misonix 3000 for 10 minutes. If you want to create solutions greater in quantities?, the sonicator? equipped with Flocells?, capable of continuously processing up to 20 l/min of solution.

The resulting mixture is placed in a 1-litre separating funnel, dripped by gravity. slowly, in a funnel equipped with a paper filter for 1300/80 separations. The filtrate is collected in a flask. If the solutions to be filtered are too dense and/or concentrated for gravity filtration, you can? intervene using vacuum and/or reduced pressure filtration. In this case the flask for filtering has a lateral tail open on the upper side which, through a rigid tube, can be connected to a vacuum pump. On the top? of the flask, a neoprene gasket is placed, and a Buchner funnel is placed, the bottom of which is covered with filter paper for 1300/80 separations. By then activating the vacuum pump, the solution is sucked up, precipitates to the bottom of the flask and is separated from the solid material. To eliminate the impurities of the solution, and not clog the? plant, you can? to use Celite? 545 which has the average particle size from 0.02mm to 0.1mm. The pores of the paper are therefore not clogged and the holes more? free allow very fine particles to pass unhindered. Of the solution obtained you measure the quantity? of Ag through atomic absorption which must be between 0.01 mg/l and 20 g/l, preferably 10 mg/l. The additive is prepared.

In a second beaker we added 414 ml of purified water CAS 7732-18-5 and stirred magnetically at 6,000 RPM. In a 1 liter separating funnel, we slowly dripped by gravity, always in the second beaker, 112 ml of a solution of photocatalytic titanium dioxide (TiO2) whose active principle is Ti content, determined through absorption atomic according to EPA 6010D:2018 ? of 4.499 mg/Kg and stirred for 30 minutes. Subsequently, always in the same 1 liter separating funnel, we dripped by gravity? slowly 474 ml of previously prepared additive containing 10 mg/kg of Ag and stirred for 30 minutes. After magnetic stirring, the mixture is emulsified at 11,500 RPM for 30 minutes. A third solution according to the invention? what? prepared.

EXAMPLE 4

Preparation of 1 liter of solution:

Water based

Using a percentage of additives preferably from 1 g per 1 liter of solution to be made, 474 ml of an aqueous solution of halide anions is added to a beaker, to which is added a quantity of Silver Chloride 99.998% (CAS 7783-90-6) having density? of 143.32 g/mol, traces of heavy metals present ?25 PPM, powder. The prepared ingredients are dispersed in the beaker with the H2O on a magnetic stirrer at about 6,000 RPM, the operation lasts about 60 minutes. Subsequently the mixture is homogenized at 12,000-15,000 RPM with a shear emulsifier for about 30 minutes. Yet another process which consists in the sonication of the previously obtained compound using a 600 Watt Misonix 3000 for 10 minutes. If you want to create solutions greater in quantities?, the sonicator? equipped with Flocells?, capable of continuously processing up to 20 l/min of solution.

The resulting mixture is placed in a 1-litre separating funnel, dripped by gravity. slowly, in a funnel equipped with a paper filter for 1300/80 separations. The filtrate is collected in a flask. If the solutions to be filtered are too dense and/or concentrated for gravity filtration, you can? intervene using vacuum and/or reduced pressure filtration. In this case the flask for filtering has a lateral tail open on the upper side which, through a rigid tube, can be connected to a vacuum pump. On the top? of the flask, a neoprene gasket is placed, and a Buchner funnel is placed, the bottom of which is covered with filter paper for 1300/80 separations. By then activating the vacuum pump, the solution is sucked up, precipitates to the bottom of the flask and is separated from the solid material. To eliminate the impurities of the solution, and not clog the? plant, you can? to use Celite? 545 which has the average particle size from 0.02mm to 0.1mm. The pores of the paper are therefore not clogged and the holes more? free allow very fine particles to pass unhindered. Of the solution obtained is measured the quantity? of Ag through atomic absorption which must be between 0.01 mg/l and 20 g/l, preferably 100 mg/l. The additive is prepared.

In a second beaker we added 414 ml of purified water CAS 7732-18-5 and stirred magnetically at 6,000 RPM. In a 1 liter separating funnel, we slowly dripped by gravity, always in the second beaker, 112 ml of a solution of photocatalytic titanium dioxide (TiO2) whose active principle is Ti content, determined through absorption atomic according to EPA 6010D:2018 ? of 4,499 mg/kg. and stirred for 30 minutes.

Subsequently, always in the same 1 liter separating funnel, we dripped by gravity? slowly 474 ml of previously prepared additive containing 100 mg/kg of Ag and stirred for 30 minutes. After magnetic stirring, the mixture is emulsified at 11,500 RPM for 30 minutes. A fourth solution according to the invention? what? prepared.

EXAMPLE 5

Color results

Solutions obtained according to Examples 1 to 4 were applied on banknotes of 20 ? through an HVLP system, with a 0.3 mm nozzle, Sata 4400 B airless model. They were applied according to different concentrations. Preparation of specimens

The banknotes were shielded with a non-absorbent sheet on 50% of the surface, in order to be able to verify the chromatic impact of the solutions and establish any color variations.

We applied the solutions on banknotes to the following quantities: 1 g/m<2>, 2 g/m<2>, 3 g/m<2>, 4 g/m<2>, 5 g/m<2> , 6 g/m<2>, 7 g/m<2>, 8 g/m<2>,9 g/m<2>, 10 g/m<2>, 11 g/m<2>, 12 g/m<2>, 13 g/m<2>, 14 g/m<2>, 15 g/m<2>, 16 g/m<2>, 17 g/m<2>, 18 g/ m<2>, 19 g/m<2 >and 20 g/m<2>. Colorimetric variation results:

Banknotes coated with the solution of Example 1

Banknotes from 1 g/m<2 >to 7 g/m<2 >= Imperceptible;

Banknotes from 8 g/m<2 >to 12 g/m<2 >= Barely perceptible; Banknotes from 13 g/m<2 > to 17 g/m<2 >= Perceptible;

Banknotes from 18 g/m<2 > to 20 g/m<2 >= marked.

Banknotes coated with the solution of Example 2

Banknotes from 1 g/m<2 >to 8 g/m<2 >= Imperceptible;

Banknotes from 9 g/m<2 >to 13 g/m<2 >= Barely perceptible;

Banknotes from 14 g/m<2 > to 17 g/m<2 >= Perceptible;

Banknotes from 18 g/m<2 > to 20 g/m<2 >= marked.

Banknotes coated with the solution of Example 3

Banknotes from 1 g/m<2 >to 8 g/m<2 >= Imperceptible;

Banknotes from 9 g/m<2 >to 12 g/m<2 >= Barely perceptible;

Banknotes from 13 g/m<2 > to 17 g/m<2 >= Perceptible;

Banknotes from 18 g/m<2 > to 20 g/m<2 >= marked.

Banknotes coated with the solution of Example 4

Banknotes from 1 g/m<2 >to 6 g/m<2 >= Imperceptible;

Banknotes from 7 g/m<2 >to 12 g/m<2 >= Barely perceptible;

Banknotes from 13 g/m<2 > to 15 g/m<2 >= Perceptible;

Banknotes from 16 g/m<2 > to 20 g/m<2 >= Marked.

EXAMPLE 6

A) Photocatalytic analysis

To analyze the photocatalytic solutions based on amorphous colloidal titanium dioxide obtained according to what is reported in Examples 1 to 4, ? was used a spectroscope UV-Vis laser beam that measures the? photocatalytic through absorbance variations resulting from the decomposition of pollutants (organic pigments) by a photocatalyst. ? basically constituted by a? unit? (sensor unit) which includes: two lamps, one for UV (black light) and one for visible light, an emitting element and a light receiving element. The incident light beam? characterized by the wavelength relative to the absorbance of Methylene Blue, 660 nm. At the intensity of each light signal that reaches the receiver corresponds proportionally to an electric signal for which, by defining the transmittance T as the fraction of incident light that is transmitted by a material, the instrument will detect? this quantity with %T = (Vn-V0)/(V100-V0) x 100 in which the denominator shows the electrical signal relating to the incident light beam (acquired by the receiver placing a completely reflecting surface) while the numerator c?? the electrical signal relating to the light beam transmitted after a time n. As can be seen in the formula, both electrical signals are reduced by the term V0 relating to that portion of light which does not reach the receiver (obtained by placing the sensor on its side in such a way that the receiver can acquire only an infinitesimal fraction of the transmitted beam ). What has been said so far can? clearly be extended also to the absorbance, which is defined as the decimal logarithm of the reciprocal of the transmittance: A = log10(1/T). Consequently, the? output of the instrument will be able? be expressed in terms of Transmittance (%T), Absorbance (ABS) and/or Voltage (V). The instrument is calibrated before each analysis. Furthermore, the tool equipped with two independent channels, CH1 and CH2, which allow simultaneous measurements on portions of a substrate treated and untreated with titanium dioxide. Four comparative analyzes were performed, each on a different substrate, comparing each photocatalytic solution with an uncoated portion that we will call Tal Quali (As Such).

Preparation of specimens

The substrates were coated by spray coating with the titanium dioxide solutions according to what is reported in Examples 1 to 4, by spraying on the surface to be analyzed a quantity of 10 ml/m<2 >respectively, with an HVLP system, with a 0.3 mm nozzle, Sata 4400 B airless model.

Results:

From the graph of Figure 4 it is clear that the best activity? photocatalytic in terms of speed? of decomposition of organic compounds deposited on the surface, after 60 minutes, and parity? of quantity? applied to the substrate that of the solution of Example 1, setting the absorbance (ABS) at -0.019321.

B) Global migration analysis in aqueous food simulant by total immersion

For the realization of this analysis of conformity? food, according to EN 11861:2002 and EN 11863:2002, so? as established by the D.M.72 of 09/05/2019 which updates the D.M. 21/03/73 Reg. 1935/2004.

Preparation of specimens

The substrates were coated by spray coating with the solution of Example 1 by spraying on the surface to be analyzed a quantity of 5 ml/m<2 >with an HVLP system, with a 0.3 mm nozzle, Sata 4400 B airless model. The specimens are 5 x 5 cm stainless steel plates, so? as established by law. The simulant used for the test, cos? as established by the legislation, ? 3% (w/v) acetic acid. Test temperature: 40?C, days of exposure: 10 days. The laboratory test is repeated 3 times, both on the specimens treated with (10), and on specimens as such (not treated).

Results:

The result obtained in all 6 cases analyzed?: NQ (NQ = not quantifiable, indicates a value lower than LoQ).

The product ? therefore compliant to come into contact with food substances.

Legislative references: D.M.72 of 09/05/2019 which updates the D.M. 21/03/73 Reg. 1935/2004.

The calculations were made assuming that 1 kg of food comes into contact with 6 dm<2 > of product.

C) Analysis with Bioluminometer

Bioluminometers are able to detect in a few seconds the presence of ATP (adenosine triphosphate), a molecule present in all animal, vegetable, bacterial, yeast and mold cells.

? a portable instrument which, combined with Lucipac A3 Surface swabs, detects ATP+AMP+ADP contamination in real time, linked to bacterial and organic contamination, and therefore to the degree of cleanliness of the surfaces.

The test, quick and accurate, ? usable for sanitization control in all areas, for example healthcare, HO.RE.CA, industrial, public offices, etc. and for the verification of a substrate of any kind.

Are you 50 bills? they were withdrawn from a vending machine (ATM) and placed in a wallet.

Preparation of specimens

The following day, three banknotes were coated with 5 g/m<2 > of the solution of EXAMPLE 2 with an HVLP system, with a 0.3 mm nozzle, Sata 4400 B airless model.

All banknotes were exposed to UVA light for 3 hours and subsequently analyzed with the bioluminometer.

Results:

The simple average of the three unprocessed banknotes ? of 1,825 RLU.

The simple average of the three banknotes treated with the solution of EXAMPLE 2 ? of 48 RLU.

The reduction delta is: 97.38%.

D) Analysis on banknotes - SARS-Cov-2 virus

Were analyzes performed on viral strains according to ISO 18184:2019 ?Textiles ? Determination of antiviral activity of textile products?.

The banknotes were coated by spray coating with the solution of EXAMPLE 2, by spraying on the surface to be analyzed two quantities i.e. 3 g/m<2 >and 6 g/m<2 >with an HVLP system, with a 0.3 mm nozzle, Sata 4400 B airless model.

The procedure provides for the comparative analysis between treated specimens and three untreated specimens.

Before testing, all samples were sterilized with UV-A rays for 4 hours;

Dimension of treated and untreated specimens: 20 x 20 mm; The viral strain used: SARS-CoV-2_COV2019 ITALY/INMI1; Test inoculum volume: 300 uL.

Test temperature: 25?C ? 1?C;

Incubation temperature: 37?C ? 1?C;

Contact time: 1 hour;

Permissive host cell line: TRUE E6.

Calculation of? Activity? antiviral

The activity antiviral ? calculated with the following formula:

Mv = lg (Va) ? lg (Vc) (???)

Where

- Mv ? the evaluation of? activity? antiviral;

- lg (Va) the logarithm of the mean of TCID50 of the three replicates at time T0 detected on the control;

- lg (Vc) the logarithm of the mean of TCID50 of the three replicates at time T detected on the treated sample Log TCID50 inoculum: 4.75.

Results:

Treated sample 3 g/m<2 >(% reduction with respect to T0) = 82.22%;

Treated sample 6 g/m<2 >(% reduction with respect to T0) = 94.38%.

The results of the assays are reported in the tables of Figure 5.

E) Artificial aging according to ASTM G155/13.

The purpose of the experiment? simulate accelerated aging both on specimens of plastic material treated with photocatalytic solutions obtained according to Example 1, and on specimens as such. This operation is performed inside the accelerated aging chamber. The aging chamber simulates the environmental conditions of light and temperature, one of the main causes of material aging.

Test parameters according to ASTM G155/13:

Equipment used: Q-Sun;

Lamps: 3 x 1500 Watt air-cooled xenon lamps;

Filter used: Daylight Q;

Black panel temperature (?C): 63 ?3;

Humidity? of the room (%): 65 ?5;

Irradiance at 340 nm (W/m2nm); 0.35

Exposure cycle: 18 minutes of light and rain for every 102 minutes of light only;

Test duration (h): 1000

For color measurement and to highlight chromatic variations, we referred to one of the most? used, the CIELAB system, in which the three coordinates that describe the color space that the human eye perceives, are indicated with the letters L* (brightness), a* (first coordinated colour) and b* (second coordinated colour) . In Lab space, then, a color is defined by specifying three coordinates: the luminosity? L* which goes by convection from 0 (zero brightness) to 100 (maximum brightness, in particular the white chosen as a reference), the a* coordinate (which expresses red when it is positive and green when it is negative) and the coordinate b* (which expresses yellow when it is positive and blue when it is negative). Can the coordinates a* and b* vary from minus to pi? infinite, but for L*=0 and L*=100, a* and b* can only assume the value 0.

This color space is used to calculate the visual difference between two colors, ?E, using this formula:

?And= ? (difference between the values of L)<2>+ (difference between the values of a)<2>+(difference between the values of b)<2 >(??). Results:

Sample as it is: L*=86.58 a*=-14.88 b=60.57

Sample with 10 after 1,000h.: L*=85.91 a*=-14.09 b=61.22 ?E= 1.22

In practice, the values of ?E are a way to communicate the difference between the two colors.

This list of values of ?E pu? serve as a guide for interpreting the psychometric significance of color differences:

< 0.2: the difference is not ? perceptible;

Between 0.2 and 0.5: the difference? very small;

Between 0.5 and 1.5: the difference? small;

From 2 to 3: c'? a discernible color change;

From 3 to 6: the difference? quite distinguishable;

From 6 to 12: strong color difference, typical of poor quality systems;

> 12: means different colors.

Claims (19)

1. A solution for the antibacterial and antiviral treatment of a substrate, in particular for the treatment of coins, banknotes, tokens and the like, comprising titanium dioxide and one or more? blend additives. 2. The solution to activities? antibacterial and antiviral according to claim 1, wherein said solution is an aqueous solution, or an alcoholic solution or a water/alcohol solution. 3. The solution to activities? antibacterial and antiviral according to claim 2, wherein said alcoholic solution is based on ethanol. 4. The solution to activities? antibacterial and antiviral according to any one of the preceding claims, wherein said titanium dioxide is amorphous photocatalytic titanium dioxide. 5. The solution to activities? antibacterial and antiviral according to claim 4, wherein said amorphous photocatalytic titanium dioxide is in colloidal form. 6. The solution to activities? antibacterial and antiviral according to any one of the preceding claims, wherein said titanium dioxide is included in a quantity? of about 0.5%-3% (w/w). 7. The solution to activities? antibacterial and antiviral according to any one of the preceding claims, wherein said additive is represented by titanium dioxide powder. 8. The solution to activities? antibacterial and antiviral according to the previous claim, wherein said additive represented by powdered titanium dioxide? chosen between: - powdered titanium dioxide of the Anastasio type, - powdered titanium dioxide of the Rutile type, or - powdered titanium dioxide of the Brookite type; or from a mixture thereof. 9. The solution to activities? antibacterial and antiviral according to any one of the preceding claims, wherein said additives can be selected from the group comprising: - silver, - copper, - soccer. 10. The solution to activities? antibacterial and antiviral according to claim 9, wherein said silver can be in the form chosen from: silver chloride, silver nitrate, silver acetate, silver phosphate glass, silver zeolite, silver copper zeolite, silver sodium hydrogen zirconium phosphate, silver zinc zeolite. 11. The solution to activities? antibacterial and antiviral according to claim 9, wherein said copper can be in the form selected from: Bis(1-hydroxy-1H-pyridine-2-thionato-O,S)copper (copper pyrithione), Bis(N-cyclohexyldiazenium-dioxy)-copper, copper hydroxide, copper oxide (I ), copper(II) oxide, copper sulfate pentahydrate, copper thiocyanate, copper(II) carbonate-copper(II) hydroxide (1:1), copper powder, copper granules. 12. The solution to activities? antibacterial and antiviral according to claim 9, wherein said calcium can be in the form chosen from: calcium oxide, calcium magnesium oxide, calcium hydroxide, calcium dihydroxide, caustic lime, hydrated lime, slaked lime, lime, burnt lime, dolomitic lime, Quicklime. 13. The solution to activities? antibacterial and antiviral according to any one of the preceding claims, wherein said additives can be selected from the group comprising: Bronopol, salicylic acid, zinc, zinc pyrithione, calcium and magnesium oxide, chlorine dioxide. 14. A method for preparing the solution according to any one of claims 1 to 13, comprises the steps of: I) adding water to photocatalytic titanium dioxide; II) add to the solution obtained from phase I) one or more? additives. 15. The method for preparing the solution according to the preceding claim, comprising the further step of emulsifying at about 11,500 RPM for about 30 minutes. 16. The method for preparing the solution according to claim 14 or 15, wherein in step I) the titanium dioxide is? in a quantity about 0.5%-3%, preferably about 0.9-1.2 (w/w) and more? preferably about 0.99% (w/w). A method of treating a substrate with the solution according to any one of claims 1 to 13 comprising the steps of: - applying the solution according to any one of claims 1 to 13, - possibly a drying phase, at room temperature or by heating, in which said substrate ? chosen from the group comprising wherein said substrate ? represented by coins, banknotes, tokens, certificates, watermarked paper, checks and revenue stamps, cash registers, tax bands, passport paper, visa paper, tickets for events (concerts, theater shows, exhibitions), meal voucher paper, certificates of qualifications. 18. The method for treating a substrate according to the preceding claim wherein in step I) ? applied a quantity? of solution from 5 to 15 g/m<2>, preferably of 6 g/m<2>. 19. The method according to claim 17 or 18, wherein said application is conducted for spray application or for flexographic or immersion printing.