JP7713212B2 - Aerosol products for hand sanitizer - Google Patents

Description

This invention relates to an aerosol product that contains a disinfectant to kill bacteria, mold, etc. that are attached to the user's hands and fingers.

Conventionally, disinfectants containing ethanol or other active ingredients have been known to kill bacteria, mold, and other contaminants on the user's hands and fingers.

For example, Patent Document 1 discloses, in Example 1, an aerosol product in which a stock solution consisting of benzalkonium chloride, 99% isopropyl alcohol, glycerin, and purified water is placed in an aerosol pressure-resistant container and carbon dioxide gas is filled as a propellant, and in Example 2, an aerosol product in which a stock solution consisting of benzalkonium chloride, 99% ethanol, and purified water is placed in an aerosol pressure-resistant container and carbon dioxide gas is filled as a propellant.

Japanese Patent Application Publication No. 6-327750

However, in the aerosol product of Patent Document 1, when the undiluted disinfectant is sprayed from the nozzle and applied to the user's hands, a high concentration of lower alcohol such as isopropyl alcohol or ethanol is sprayed to provide sufficient sterilizing and disinfecting properties even if some of it evaporates on the way from the nozzle to the hands. Since such lower alcohol is a flammable liquid, it may ignite if there is a fire nearby and spread from the source of the fire, causing a fire. In particular, since the spread of the novel coronavirus disease (COVID-19), public awareness of disinfection has increased, and disinfectants are frequently used in places where there is a fire, such as in kitchens and dining tables, so there are concerns about the spread of fire due to ignition caused by the use of disinfectants containing lower alcohol such as isopropyl alcohol or ethanol.

On the other hand, if the content of lower alcohols such as isopropyl alcohol or ethanol is too low due to concerns about flammability, it will not be able to kill bacteria, mold, etc., and will therefore be useless as a disinfectant.

The present invention aims to provide an aerosol product for disinfectant containing a lower alcohol with 1 to 3 carbon atoms that can kill bacteria, mold, etc., and that is unlikely to cause a fire by spreading from the source of fire even if it ignites in the presence of a flame close by, such as in the kitchen or on the dining table.

[1] That is, the present invention provides an aerosol product for hand disinfectant, which comprises an outer container, a hand disinfectant that contains 20 w/v% to 65 w/v% of a lower alcohol having 1 to 3 carbon atoms , a quaternary ammonium salt, an acid, a salt corresponding to the acid, and water and has a pH of 3.0 to 5.0 at 25°C , and only nitrogen as a non-flammable compressed gas filled in the outer container, wherein an ignited burner is placed 15 cm away from a nozzle for spraying the hand disinfectant, and when the hand disinfectant is sprayed from the nozzle so as to pass through the upper third of the burner flame, the burner flame ignites and the flame length, which is the length of the burner flame extending in the downstream direction of the spray, is 0 to 20 cm.

[2] The aerosol product for hand disinfection according to [1] above, characterized in that the acid is phosphoric acid .

According to the present invention, an aerosol product related to a disinfectant containing a lower alcohol having 1 to 3 carbon atoms can kill bacteria, mold, etc., and furthermore, even if it ignites in the presence of a flame close to home, such as in the kitchen or on the dining table, it is difficult for the fire to spread from the source and cause a fire.

FIG. 1 is a central cross-sectional view of an aerosol product for hand sanitizer in a first embodiment of the present invention. FIG. 11 is a central cross-sectional view of a hand sanitizer aerosol product in a second embodiment of the present invention.

The following is a detailed explanation of an embodiment of the hand sanitizer aerosol product of the present invention. Note that when the range in the explanation is indicated by "~", it includes the upper and lower limits.

The outer container 1 is the outermost part visible to the user in the hand disinfectant aerosol product of the present invention, and is a member that contains the hand disinfectant 2 inside. Since the inside of the outer container 1 is filled with a non-flammable compressed gas, it has pressure resistance so that it does not break below a certain pressure, such as a metal such as an aluminum alloy or a synthetic resin having a certain thickness. In this embodiment, the outer container 1 is a hollow cylinder with a bottom and an opening at the top. The opening at the top is sealed by a mounting cup 3 as shown in FIG. 1. In addition, when the hand disinfectant 2 described later is acidic with a pH of 3.0 to 5.0 at 25°C, in order to prevent the outer container 1 from being corroded and having holes, it is preferable that the inside of the outer container 1 that comes into contact with the hand disinfectant 2 has a coating layer applied to a certain thickness with a polyolefin such as polyethylene, polypropylene, or polyvinyl chloride, or a fluororesin such as polytetrafluoroethylene.

Next, we will explain the hand sanitizer 2 contained in the outer container 1.

In the present invention, the lower alcohol having 1 to 3 carbon atoms is an alcohol having 1 to 3 carbon atoms in the molecule, such as methanol, ethanol, and isopropyl alcohol. By using such a lower alcohol, it is possible to destroy the cell membranes of bacteria, mold, and the like, thereby preventing harm to the human body, such as diseases caused by them. In addition, viruses can be destroyed by destroying the viral envelope and coagulating proteins such as enzymes.

The content of the lower alcohol having 1 to 3 carbon atoms in the hand disinfectant 2 is preferably 20 w/v% to 65 w/v%, and more preferably 25 to 63 w/v%. When the content of the lower alcohol having 1 to 3 carbon atoms is within this range, it is possible to kill or inactivate bacteria, mold, viruses, etc., and furthermore, when combined with an acid, it is more effective against viruses. The concentration is expressed as a percentage of grams (g) per 100 mL.

A quaternary ammonium salt can be blended in the hand disinfectant 2 of the present invention. The quaternary ammonium salt is a compound consisting of a quaternary ammonium ion and a counter anion, as generally represented by the chemical formula N ⁺ RX ^- (R: alkyl group, X ^- : chloride ion, etc.). Specific examples of the quaternary ammonium salt include benzalkonium chloride, benzethonium chloride, methylbenzethonium chloride, cetylpyridinium chloride, didecyldimethylammonium chloride, hexadodecyltrimethylammonium bromide, and tetraammonium bromide. These quaternary ammonium salts can be used alone, but may be used in combination of two or more. In this way, the inclusion of a quaternary ammonium salt makes it easier to destroy the cell membranes of bacteria, mold, etc., and can kill them. Furthermore, the envelopes of enveloped RNA viruses such as coronaviruses (especially COVID-19), influenza viruses, Ebola viruses, and human immunodeficiency viruses, and enveloped DNA viruses such as herpes viruses and smallpox viruses, can be easily destroyed and inactivated.

The content of quaternary ammonium salt in hand disinfectant 2 is preferably 0.01 w/v% to 2.0 w/v%, and more preferably 0.03 w/v% to 1.0 w/v%. If the content of quaternary ammonium salt is within this range, cell membranes of bacteria, etc. are more likely to be destroyed.

An acid can be added to the hand disinfectant 2 of the present invention. When present together with ethanol, quaternary ammonium salts, etc., the acid destroys the capsid that protects nucleic acid, promoting the penetration of ethanol, quaternary ammonium salts, etc. into cells, and further enhancing the effectiveness of inactivating a wide range of RNA and DNA viruses, regardless of whether they are enveloped or not.

Specific examples of acids that are preferred include organic acids such as citric acid, malic acid, acetic acid, boric acid, lactic acid, formic acid, oxalic acid, and propionic acid, and inorganic acids such as phosphoric acid and sulfuric acid. These acids can be used alone or in combination of two or more.

The acid content of the hand disinfectant 2 is preferably 0.1 w/v% to 3.0 w/v%, and more preferably 0.2 w/v% to 2.5 w/v%. When the acid content is within this range, it can be effective in inactivating viruses and killing bacteria.

In the hand disinfectant 2 of the present invention, a salt of the acid can be blended. The salt of the acid is a salt corresponding to the organic acid or inorganic acid described above. Specifically, for example, when citric acid is used as the acid, the salt is sodium citrate, potassium citrate, calcium citrate, etc., when malic acid is used, the salt is sodium malate, potassium malate, calcium malate, etc., and when phosphoric acid is used, the salt is sodium phosphate, potassium phosphate, calcium phosphate, etc. In this way, by including a salt corresponding to the acid, the hand disinfectant 2 has a pH in a predetermined range, and even if the lower alcohol having 1 to 3 carbon atoms or water in the hand disinfectant 2 volatilizes slightly after long use, large fluctuations in pH are suppressed, so that the user can use it in a predetermined range of liquidity.

The content of the acid salt in the hand sanitizer 2 is preferably 0.1 w/v% to 3.0 w/v%, and more preferably 0.2 w/v% to 2.5 w/v%. When the content of the acid salt is within this range, the pH of the hand sanitizer 2 can be maintained within a specified range.

The water of the present invention is a solvent for making a homogeneous solution of a lower alcohol having 1 to 3 carbon atoms, an acid, a salt of the acid, and a quaternary ammonium salt. Specifically, the water is preferably water conforming to the Japanese Pharmacopoeia standard, and examples of the water include ordinary water such as tap water and well water, purified water obtained by treating ordinary water by distillation, ion exchange treatment using an ion exchange membrane, ultrafiltration treatment using an ultrafiltration membrane, or a combination thereof, and sterilized purified water obtained by sterilizing purified water by heating or the like. The blending ratio of water is the remainder excluding the lower alcohol having 1 to 3 carbon atoms, an acid, a salt of the acid, and a quaternary ammonium salt used in the present invention, and is preferably 30 w/v% to 75 w/v%, and more preferably 32 w/v% to 65 w/v%.

In addition to the above-mentioned ingredients, hand disinfectant 2 may contain, as necessary, polyhydric alcohols such as glycerin, propylene glycol, butylene glycol, and sorbitol; moisturizing agents such as polysaccharides or salts thereof such as hyaluronic acid and sodium hyaluronate; thickeners such as hydroxyethyl methylcellulose and hydroxypropyl methylcellulose; fragrances; and colorants. For example, adding a moisturizing agent can further prevent rough skin.

Hand disinfectant 2 containing the above-mentioned components has a pH at 25°C, which indicates the degree of acidity or alkalinity, of preferably 3.0 to 5.0, and more preferably 3.0 to 4.0. When the pH of hand disinfectant 2 is in this range, it is effective in killing bacteria and inactivating various viruses.

When the hand disinfectant 2 thus formulated is sprayed from the nozzle 71, the average particle diameter at 20 cm from the nozzle 71 is preferably 15 to 150 μm, and more preferably 20 to 120 μm. If the average particle diameter is within this range, when the hand disinfectant 2 is sprayed from the nozzle 71 of the aerosol product and adheres to the user's hands, it exhibits sufficient bactericidal and disinfecting properties even if the lower alcohol with 1 to 3 carbon atoms evaporates during the process, and since it does not contain an excessive amount of lower alcohol with 1 to 3 carbon atoms, it is difficult for the fire to spread from the source even if it ignites a nearby fire. The average particle diameter is preferably measured by a laser diffraction/scattering method.

The non-flammable compressed gas of the present invention is filled into the outer container 1 together with the hand disinfectant 2, and is a gas that does not ignite or burn when exposed to fire at normal temperatures of about 10 to 30°C, which are normally used, and is in a state of pressure higher than atmospheric pressure within the outer container 1. In the first embodiment, the non-flammable compressed gas is discharged to the outside together with the hand disinfectant 2 by pressing the actuator 7 described below, and in the second embodiment, the bag body 11 is pressed. Specifically, the non-flammable compressed gas is preferably at least one selected from nitrogen, carbon dioxide, nitrous oxide, helium, and argon. If the non-flammable compressed gas is one of these gases, it will not ignite even if a fire is present near the user when it is discharged from the spray nozzle 71, and therefore the aerosol product for hand disinfectant of the present invention can be used safely.

The pressure of the non-flammable compressed gas filled in the outer container 1 together with the hand sanitizer 2 is preferably 0.10 MPa or more and less than 1.0 MPa at 35°C, more preferably 0.2 to 0.9 MPa, and most preferably 0.6 to 0.85 MPa. When the pressure of the non-flammable compressed gas is within this range, the hand sanitizer 2 is smoothly discharged by the non-flammable compressed gas.

In the first embodiment, the aerosol product is composed of an outer container 1, a hand sanitizer 2, a mounting cup 3, a stem 4, an elastic spring 5, a tube 6, an actuator 7, etc., as shown in FIG. 1. The hand sanitizer 2 and non-flammable compressed gas contained in the outer container 1 are at a higher pressure than the outside of the outer container 1. Therefore, when the actuator 7 is pressed down, the elastic spring 5 also presses down the stem 4 against the biasing force, and the stem hole 41 communicates with the inside of the bag body 11, and the hand sanitizer 2 and non-flammable compressed gas are discharged to the outside from the spray nozzle 71 of the actuator 7 through the bag body 11, the tube 6, the stem 4. In addition, the aperture of the spray nozzle 71 of the actuator 7 is preferably 0.05 to 1 mm, more preferably 0.1 to 0.7 mm, and most preferably 0.2 to 0.4 mm. When the aperture of the spray nozzle 71 is in this range, the hand sanitizer 2 is discharged in a mist form by the non-flammable compressed gas.

In the second embodiment, as shown in FIG. 2, the aerosol product has a bag body 11 housed in an outer container 1, and the hand sanitizer 2 is contained in the bag body 11. The bag body 11 is a flexible member. Since the bag body 11 is housed in the outer container 1, the hand sanitizer 2 contained in the bag body 11 does not directly contact the outer container 1, so that corrosion of the outer container 1 can be prevented when the hand sanitizer 2 contains acid and is acidic, and since it is constantly pressed by the non-flammable compressed gas filled in the space between the outer container 1 and the bag body 11, the hand sanitizer 2 contained in the bag body 11 can be used up to the end, and even if the aerosol product is turned upside down from the state in FIG. 1 and sprayed with the actuator 7 at the bottom, the hand sanitizer 2 is smoothly discharged. In addition, when the hand disinfectant 2 contained in the bag 11 is acidic, it is stored at a pressure higher than normal pressure, and there is concern that the bag 11 may deteriorate or break. Therefore, the bag 11 is preferably made of polyolefins such as polyethylene, polypropylene, and polyvinyl chloride, or fluororesins such as polytetrafluoroethylene, at least on the surface that contacts the hand disinfectant 2, so as not to be hydrolyzed. Among polyethylenes, high-density polyethylene with a specific gravity of 0.92 to 0.96 and a deflection temperature under load of 130°C or less as specified in JIS K7191-3 or the like is more preferable. The above polyolefins and fluororesins may of course be formed as copolymers. And, in order to prevent non-flammable compressed gas from flowing into the bag 11 or to prevent the contained hand disinfectant 2 from leaking from the bag 11 into the space S, other synthetic resins, metals such as aluminum, and metal oxides such as silicon dioxide and aluminum trioxide may be laminated on the outside of the above-mentioned polyolefins such as polyethylene and polypropylene or fluororesins to form a multi-layer film of two or more layers.

The aerosol product of the second embodiment is composed of hand disinfectant 2, mounting cup 3, stem 4, elastic spring 5, tube 6, actuator 7, etc., as in the first embodiment. The bag 11 contained in the outer container 1 is constantly pressed by the non-flammable compressed gas filled in the space S between the outer container 1 and the bag 11. Therefore, when the actuator 7 is pressed down, the elastic spring 5 also presses down the stem 4 against the biasing force, so that the stem hole 41 communicates with the inside of the bag 11, and the hand disinfectant 2 pressed by the non-flammable compressed gas through the bag 11 is discharged to the outside from the spray nozzle 71 of the actuator 7 through the tube 6 and stem 4. As in the first embodiment, the aperture of the spray nozzle 71 of the actuator 7 is preferably 0.05 to 1 mm, more preferably 0.1 to 0.7 mm, and most preferably 0.2 to 0.4 mm.

Below, the hand disinfectant 2 of the present invention will be specifically described. Note that the present invention is not limited to the following examples.

Example 1
At room temperature of 20°C, 20 g of ethanol as a lower alcohol having 1 to 3 carbon atoms, 0.5 g of phosphoric acid as an acid, 0.25 g of trisodium phosphate as a salt corresponding to the acid, 0.1 g of concentrated benzalkonium chloride solution 50 as a quaternary ammonium salt (0.05 g as benzalkonium chloride), 0.2 g of glycerin as a moisturizer, and purified water as the remainder were added to a 200 ml Griffin beaker and stirred to obtain a total of 100 ml of hand sanitizer.

<Examples 3 and 5, Comparative Examples 1 and 2>
In Examples 3 and 5, a lower alcohol having 1 to 3 carbon atoms and, if necessary, an acid, a salt corresponding to the acid, and a quaternary ammonium salt were formulated as shown in Table 1, and a total of 100 ml of hand disinfectant was obtained in the same manner as in Example 1.

Then, the above-mentioned hand disinfectant 2 was placed in the outer container 1, nitrogen was sealed in as a non-flammable compressed gas so that the internal pressure was 0.8 MPa, and an actuator 7 with a spray nozzle diameter of 0.3 mm was attached to produce an aerosol product in the second embodiment. The performance of the aerosol product containing the hand disinfectant 2 thus obtained was confirmed by the following evaluation method. The aerosol product in the second embodiment can also be produced and evaluated in the same manner.

[Disinfecting and disinfecting test]
Regarding the sterilization and disinfection properties, the effect of the hand disinfectant 2 sprayed from the aerosol product against Escherichia coli and Staphylococcus aureus was confirmed. Specifically, first, assuming that the aerosol product would be sprayed on the hands when used, various actuators 7 with different diameters of the spray nozzle 71 were pressed with a predetermined force and sprayed for about 1 second on about 10 ⁵ bacteria smeared on a plate medium in a petri dish at a position 20 cm away from the spray nozzle 71. Then, each medium was cultured at 35°C for about 8 hours, and the number of bacteria was measured. Those with an efficacy of 99.9% or more of the number of bacteria killed by contact with the hand disinfectant 2 relative to the initial number of bacteria smeared on the medium were evaluated as "◎", those with an efficacy of 99% or more but less than 99.9% were evaluated as "○", and those with an efficacy of less than 99% were evaluated as "×". At this time, "◎" and "○" were judged to be excellent as having sufficient sterilization and disinfection properties, and "×" was judged to be poor as having insufficient sterilization and disinfection properties.

[Flame length test]
In accordance with the test for the length of the sprayed flame in the "Voluntary Standards for the Testing and Inspection of Aerosols, etc." (revised on April 25, 2017) by the Japan Aerosol Association, an ignited burner is placed at a position 15 cm away from the nozzle 71 of the aerosol product, and the actuator 7 is pressed with a specified force so that the hand sanitizer 2 passes through the upper third of the burner flame, and the hand sanitizer 2 is sprayed from the nozzle 71 of the aerosol product. At this time, the burner flame is ignited, and the length of the ignition flame extending from the burner flame along the downstream direction of the spray is measured. Since the flame is constantly flickering, it is measured whether it is within the range of the marks at 5 cm intervals in the background. In Table 1, the length of the ignition flame extending from the burner flame is expressed as "0-5" if it is 0 cm or more and less than 5 cm, "5-10" if it is 5 cm or more and less than 10 cm, and "10-15" if it is 10 cm or more and less than 15 cm. The length of the ignition flame extending from the burner flame was evaluated as "◎" when it was less than 5 cm, "◯" when it was 5 cm or more but less than 20 cm, and "×" when it was 20 cm or more. In this case, "◎" and "◯" were judged as excellent, meaning that the flame did not easily spread from the source of the fire, and "×" was judged as poor, meaning that the flame easily spread from the source of the fire. The results of the flame length test when hand disinfectant 2 was sprayed are shown in Table 1.

As an overall evaluation based on the results of these bactericidal disinfection tests and flame length tests, formulations that received a rating of "◎" or "○" in both the bactericidal disinfection test and the flame length test were rated as "○" as they could actually be used, while those that received an "×" rating were rated as "×" as they could not actually be used.

As shown in Table 1, the aerosol products of Examples 1 , 3, and 5 showed bactericidal disinfection against bacteria such as Escherichia coli and Staphylococcus aureus at a specified distance even though ethanol evaporated during spraying, and the length of the ignition flame extending from the burner flame, which is the source of the fire, was less than 20 cm, so it was found that it was difficult to spread even if it ignited, and it was actually usable. However, the aerosol product of Comparative Example 1 had a very short flame length and extremely low risk of fire spreading when the ethanol content was less than the specified amount, but the ethanol content was low and the ethanol evaporated during spraying, so the bactericidal disinfection was insufficient and it was difficult to actually use it. In addition , the aerosol product of Comparative Example 2 had sufficient bactericidal disinfection when the ethanol content was more than the specified amount, but the flame length was long and there was a high risk of fire spreading, so it was difficult to actually use it.

1: Outer container 11: Bag body 2: Hand sanitizer 3: Mounting cup 4: Stem 41: Stem hole 5: Elastic spring 6: Tube 7: Actuator 71: Spray nozzle S: Space

Claims (2)

An outer container;
a hand disinfectant contained in the outer container, the hand disinfectant containing 20 w/v % to 65 w/v % of a lower alcohol having 1 to 3 carbon atoms , a quaternary ammonium salt, an acid, a salt corresponding to the acid, and water, and having a pH of 3.0 to 5.0 at 25°C;
The outer container is filled with only nitrogen as a non-flammable compressed gas,
An aerosol product for hand disinfectant, characterized in that when an ignited burner is placed 15 cm away from a nozzle for spraying the hand disinfectant, and the hand disinfectant is sprayed from the nozzle so as to pass through the upper third of the burner flame, the burner flame ignites and the flame length, which is the length of the burner flame extending in the downstream direction of the spray, is 0 to 20 cm. 2. The hand sanitizer aerosol product of claim 1, wherein the acid is phosphoric acid .