CN119173142A

CN119173142A - Antimicrobial compositions

Info

Publication number: CN119173142A
Application number: CN202280077267.3A
Authority: CN
Inventors: S·阿帕沃; A·哈尔德
Original assignee: Unilever IP Holdings BV
Current assignee: Unilever IP Holdings BV
Priority date: 2021-11-24
Filing date: 2022-11-23
Publication date: 2024-12-20
Also published as: EP4436380A1; WO2023094466A1; AR127750A1

Abstract

The present invention relates to an antimicrobial composition, more particularly a liquid composition, which is not caustic on surfaces being cleaned and disinfected, such as fabrics and tableware, especially those washed by hand, and which is also useful for the sanitization of hands and other body surfaces. The present invention may also be used to develop products for use as multipurpose sanitary liquid compositions useful for cleaning/disinfecting any one or more of the above surfaces. This is achieved by combining an amino acid based surfactant having a specific pKa value with a C3-C9 alkane diol, while the composition has a pH in the range of 2.5 to 4.5.

Description

Antimicrobial compositions

Technical Field

The present invention relates to an antimicrobial composition, and more particularly to a liquid composition that is not caustic on surfaces being cleaned and disinfected, such as fabrics or dishes, especially those washed by hand, and also for the sanitization of hands and other body surfaces. The present invention may also be used to develop products for use as multipurpose sanitary liquid compositions useful for cleaning/disinfecting any one or more of the above surfaces.

Background

Disinfecting cleaning compositions are highly beneficial to individuals because proper use can generally reduce the number of pathogens and pathogens to which an individual is exposed. Such compositions may play an important role, for example, in reducing the occurrence and transmission of infectious diseases. Disinfecting compositions containing chlorine-based bleaching agents are known. These compositions are sometimes considered quite caustic because they may exhibit undesirable side effects such as corrosion, off-flavors (e.g., chlorine odors) and skin irritation or skin sensitization when contacted with an individual's skin or mucous membrane. Furthermore, surfactants such as soaps and other relatively caustic surfactants in combination with other compounds such as organic acids are known to provide relatively good antimicrobial activity. However, there are specific situations where such cleaning and disinfection is achieved when the composition is applied to a substrate by hand or in the case where the substrate is the hand itself. In such cases, consumers expect the sanitizing compositions to be mild on the hands, but still provide a high level of antimicrobial activity. Such substrates include tableware, clothing and other fabrics that are especially laundered by hand.

The present inventors have unexpectedly found during the development of various antimicrobial compositions that a combination of an amino acid based surfactant having a specific pKa value in a narrow pH range of 2.5 to 4.5 and a specific alkane diol is capable of achieving high antimicrobial activity. This is indeed surprising, since neither of these two components is known per se to have any significant antimicrobial activity. To the inventors' knowledge, such combinations of active substances have not been combined and used to provide high antimicrobial activity under the claimed conditions.

It is therefore an object of the present invention to provide antimicrobial compositions that are mild on the skin.

Disclosure of Invention

According to a first aspect of the present invention there is provided an antimicrobial composition comprising

(I) 0.01 to 2 wt% of an amino acid based surfactant having a pKa value in the range of 3 to 5;

(ii) 0.05 to 2 wt% of a C3-C9 alkane diol;

wherein the composition has a pH in the range of 2.5 to 4.5.

Detailed Description

For the avoidance of doubt, any feature of one aspect of the present invention may be used in any other aspect of the present invention. The word "comprising" is intended to mean "including", but not necessarily "consisting of. Thus, the term "comprising" is not meant to be limited to any subsequently stated elements, but optionally also includes non-specific elements of major or minor functional importance. In other words, the listed steps or options need not be exhaustive. Whenever the words "including" or "having" are used, these terms are meant to be equivalent to "comprising" as defined above. It should be noted that the examples given in the following description are intended to clarify the invention and are not intended to limit the invention to these examples per se. Except in the examples, or where otherwise explicitly indicated, all numbers in this description indicating amounts of material or conditions of reaction, physical properties of materials and/or use are to be understood as modified by the word "about". Unless otherwise indicated, numerical ranges expressed in the "x to y" format are understood to include x and y. When describing a plurality of preferred ranges in an "x-to-y" format for a particular feature, it should be understood that all ranges combining the different endpoints are also contemplated. Unless otherwise indicated, amounts used herein are expressed in weight percent, abbreviated as "wt%", based on the total weight of the composition.

Throughout this specification, the term "disinfection" refers to reducing the number of viable microorganisms in a given medium or on a given surface. Typically, disinfection involves the destruction or inactivation of microorganisms. Both animate and inanimate media and surfaces are contemplated.

The term "antimicrobial agent" refers to a compound capable of killing microorganisms, inhibiting or controlling the growth of microorganisms at a locus, and includes bactericides, fungicides and algicides, although the invention is more useful for bacteria.

The compositions of the present invention are preferably used for non-therapeutic purposes, more particularly preferably for cleaning surfaces such as those on tableware, clothing and other fabrics and body surfaces such as hands.

The composition comprises an amino acid based surfactant having a pKa value in the range of 3-5. They are preferably selected from one or more of sodium lauroyl sarcosinate, sodium oleoyl glutamate, sodium oleoyl glycinate, disodium cocoyl glutamate, sodium cocoyl glutamate, disodium lauroyl glutamate, sodium cocoyl glycinate and sodium lauroyl glycinate. Among them, the sarcosinate surfactant is more preferable than the glutamate surfactant, and the glutamate surfactant is more preferable than the glycinate surfactant. Thus, the most preferred amino acid surfactants for use in the present invention are selected from one or both of sodium lauroyl sarcosinate and sodium oleoyl sarcosinate.

The amino acid surfactant is contained in an amount of 0.01 to 2%, preferably 0.02 to 1% by weight of the composition.

The compositions of the present invention comprise a C3-C9 alkane diol. Preferred alkane diols are selected from one or more of propylene glycol, hexylene glycol, and octylene glycol. The alkane diol is comprised at 0.05 to 2%, preferably 0.05 to 1% by weight of the composition.

Without wishing to be bound by theory, the inventors believe that the selected alkane diol finds a good membrane permeabilizer, which ensures that the amino acid surfactant can then more easily enter the bacterial cells to destroy them, thereby enhancing antibacterial properties.

The composition is effective at a pH in the range of 2.5 to 4.5, preferably in the range of 2.5 to 3.5.

The composition preferably comprises an organic acid. Preferred organic acids for use in the present invention are one or more of lactic acid, glycolic acid, tartaric acid and citric acid. The most preferred acid is citric acid. The organic acid may also be present in the form of a salt. Alkali metal or alkaline earth metal salts are preferred, more preferably alkali metal salts, with sodium salts being most preferred. The composition comprises 0.1 to 5 wt%, preferably 0.5 to 3 wt%, even more preferably 1 to 2.5 wt% of an organic acid or salt thereof.

The composition is typically in liquid form. It contains a large amount of water. The water is generally present at 80-97%, preferably 90-94% by weight of the composition.

Liquid laundry detergent compositions

The composition may be provided as a laundry detergent composition which may contain a surfactant in addition to the essential ingredients of the present invention.

The laundry detergent compositions in which the present invention may be implemented are preferably in liquid form. The term "liquid" may include emulsions, suspensions, and compositions having a flowable but harder consistency, referred to as gels or pastes. The pourable liquid detergent composition preferably has a viscosity of 200 to 1,500mpa.s, preferably 200 to 700 mpa.s. Such compositions typically have an aqueous continuous phase. Preferably, the composition comprises at least 50% by weight water, more preferably at least 70% by weight water. The water is generally present in an amount of from 20% to 99.9%, preferably from 40% to 80% by weight of the composition.

Liquid laundry detergent compositions typically comprise from 1 to 30 wt%, preferably from 2 to 15 wt%, of one or more surfactants. Surfactants are generally anionic in nature. Amino acid based surfactants, which are an essential feature of the compositions of the present invention, are also anionic surfactants. However, it should be understood that throughout the specification, the use of the term "anionic surfactant" is intended to mean an anionic surfactant other than an amino acid based surfactant. Preferred anionic surfactants are organic sulphates and sulphonates having alkyl radicals containing from about 8 to about 22 carbon atoms, the term "alkyl" being used to include the alkyl portion of higher acyl radicals. Examples of such materials include alkyl sulfates, alkyl ether sulfates, alkylaryl sulfonates, alpha olefin sulfonates, and mixtures thereof. The alkyl group preferably contains 10 to 18 carbon atoms and may be unsaturated. The alkyl ether sulfate may contain 1 to 10 ethylene oxide or propylene oxide units per molecule, preferably 1 to 3 ethylene oxide units per molecule. The counter ion of the anionic surfactant is typically an alkali metal such as sodium or potassium, or an ammonia counter ion such as Monoethanolamine (MEA), diethanolamine (DEA) or Triethanolamine (TEA). Mixtures of these counterions can also be used. Sodium and potassium are preferred.

The most preferred surfactants are the alkylbenzene sulfonate types, especially Linear Alkylbenzene Sulfonates (LAS) having an alkyl chain length of 10 to 18 carbon atoms. Some alkyl sulfate surfactants (PAS) may be used, such as non-ethoxylated primary and secondary alkyl sulfates having alkyl chain lengths of 10-18.

Preferably, the composition comprises 5 to 20 wt% nonionic surfactant based on the total weight of the composition. A preferred class of nonionic surfactants for use in the present invention comprises aliphatic C ₈-C₁₈, more preferably C ₁₂-C₁₅ linear primary alcohol ethoxylates having an average of from 3 to 20, more preferably from 5 to 10 moles of ethylene oxide per mole of alcohol. Preferred nonionic surfactants are C16/18 alcohol ethoxylates.

In addition to the ingredients described above, liquid laundry detergent compositions typically contain agents such as soil release polymers, hydrotropes, cosurfactants, builders, polymeric thickeners and shading dyes. Soil Release Polymers (SRPs) help improve soil release from fabrics by modifying the surface of the fabric during laundering.

The SRP structure may also include end capping groups to control molecular weight or to alter polymer properties such as surface activity. Preferred SRPs for use in the present invention include copolyesters formed from the condensation of terephthalic acid esters and diols, preferably 1, 2-propanediol, and also include end-capped copolyesters formed from repeating units of an alkyl-capped alkylene oxide. When included, the SRP can range from 0.1 to 10%, desirably from 0.3 to 7%, and more preferably from 0.5 to 5% by weight of the composition.

The compositions of the present invention may be blended with non-aqueous carriers such as hydrotropes, co-solvents and phase stabilizers. Such materials are typically low molecular weight, water soluble or water miscible organic liquids such as C1-C5 monohydric alcohols (e.g., ethanol and n-propanol or isopropanol), C2-C6 glycols (e.g., monopropylene glycol and dipropylene glycol), C3-C9 triols (e.g., glycerol), polyethylene glycols having a weight average molecular weight (M _w) ranging from about 200 to 600, C1-C3 alkanolamines such as monoethanolamine, diethanolamine and triethanolamine, and alkylaryl sulfonates having up to 3 carbon atoms in the lower alkyl groups (e.g., sodium and potassium xylene, toluene, ethylbenzene and cumene (cumene) sulfonates). When included, the non-aqueous carrier may be present in an amount ranging from 0.1 to 3%, preferably from 0.5 to 1% by weight of the composition. Preferred hydrotropes are monopropylene glycol and glycerol.

In addition to the non-soap anionic and/or nonionic detersive surfactants described above, the liquid laundry detergent compositions of the present invention may comprise one or more co-surfactants (e.g., amphoteric (zwitterionic) and/or cationic surfactants). When included, such cosurfactants may be present in an amount ranging from 0.1 to 5% by weight of the composition.

The liquid laundry detergent composition may optionally also comprise relatively low levels of organic detergent builder or chelant material. Examples include alkali metal citrates, succinates, malonates, carboxymethyl succinates, carboxylates, polycarboxylates, aminocarboxylates and polyacetylcarboxylates. If used, the organic builder material may comprise about 0.5% to 20% by weight of the composition, preferably 1% to 10% by weight.

When the composition is a liquid laundry detergent composition, it may be diluted with water in a ratio in the range of 1:5 to 1:300 (e.g., such as a ratio of 1:50 or 1:100, 1:200) to form a wash liquor.

Liquid dishwashing composition

The compositions of the present invention may be used for the care of kitchen items, for example, appliances and dishes that may be cleaned using liquid dishwashing compositions. Various components other than the essential components claimed in the present invention are summarized as follows. Among the various ingredients, anionic surfactants, nonionic surfactants, and hydrotropes as detailed in liquid laundry detergent compositions are useful in liquid dishwashing compositions. In addition, other ingredients that may be included are detailed below:

Preferably, the composition further comprises an amphoteric surfactant. Preferably, the amphoteric surfactant is selected from the group consisting of alkylamine oxides, alkyl betaines, alkylamidopropylbetaines, alkyl sulfobetaines (sulfobetaines), alkyl glycinates, alkyl carboxyglycinates, alkyl amphoacetates, alkyl amphopropionates, alkyl amphoglycinates, alkylamidopropylhydroxysulfobetaines, acyl taurates, and acyl glutamates, having an alkyl group containing from about 8 to about 22 carbon atoms, the term "alkyl" being used for alkyl moieties including higher acyl groups. More preferably, the amphoteric surfactant is selected from alkylamidopropyl betaines, even more preferably cocamidopropyl betaines. When included, the amphoteric surfactant may be present in an amount ranging preferably from 0.1 to 5% by weight, more preferably from 0.1 to 4% by weight, even more preferably from 1 to 3% by weight. Mixtures of any of the above materials may also be used. A good combination of surfactants for use in the present invention in the form of a dishwashing composition is a combination having 1 to 30 wt% anionic surfactant and 0.1 to 5 wt% amphoteric surfactant.

The liquid dishwashing composition may preferably comprise an organic acid or salt thereof as disclosed hereinabove. Preferred is citric acid or a salt thereof, such as trisodium citrate.

Preferably, the liquid dishwashing composition further comprises water in an amount of from 5 to 99 wt%, more preferably from 10 to 90 wt%, even more preferably from 15 to 80 wt%, still more preferably from 20 to 70 wt%, yet more preferably from 30 to 65 wt%, still more preferably from 35 to 60 wt%, yet still more preferably from 40 to 55 wt%.

Preferably, the liquid dishwashing composition further comprises one or more chelants. Preferably, the composition comprises a chelating agent, which may be present in an amount of 0.1 to 5 wt%, more preferably 0.25 to 4 wt%, even more preferably 0.5 to 2.5 wt%.

The preferred chelating agent is phosphonic acid or a salt thereof. The phosphonic acid (or salt thereof) chelating agent is preferably selected from the group consisting of 1-hydroxyethylidene-1, 1-diphosphonic acid (HEDP; commercially available as Dequest (R) 2010), diethylenetriamine penta (methylenephosphonic acid) (DTPMP; commercially available as Dequest (R) 2066), hexamethylenediamine tetra (methylenephosphonic acid) (HDTMP), aminotri (methylenephosphonic Acid) (ATMP), ethylenediamine tetra (methylenephosphonic acid) (EDTMP), tetramethylenediamine tetra (methylenephosphonic acid) (TDTMP), and phosphonobutane tricarboxylic acid (PBTC). The most preferred chelating agent is 1-hydroxyethylidene-1, 1-diphosphonic acid (HEDP). Preferably the chelating agent is added to the formulation in the form of an acid.

Optionally, the liquid dishwashing composition further comprises an enzyme with or without a suitable enzyme stabilizer. Preferably, the composition further comprises an effective amount of at least one enzyme with or without a suitable enzyme stabilizer. Examples of suitable enzymes include pectate lyase, protease, amylase, cellulase, lipase, mannanase, with or without suitable stabilizers.

Preferably, the viscosity of the composition may suitably be in the range of from about 200mpa.s to about 10,000mpa.s at a shear rate of 21sec ^-1 at 25 ℃. The shear rate is the shear rate that is normally applied to a liquid when pouring from a bottle. The pourable liquid home care composition typically has a viscosity of from 200 to 1,500mpa.s, preferably from 100 to 800 mpa.s.

The liquid dishwashing composition may further comprise one or more polymers. Preferably, the polymer may be of the cationic, anionic, amphoteric or nonionic type having a molecular weight higher than 100,000 daltons. They are known to increase the viscosity and stability of liquid compositions to enhance the sensory feel of the skin during and after use and to enhance foam creaminess and foam stability. Examples of polymers include polyvinyl alcohol, polyacrylic acid, silanes, siloxanes, and mixtures thereof. If present, the polymer may be present in the composition in an amount of preferably 0.001 to 10 wt%, more preferably 0.1 to 6 wt%, still more preferably 1 to 3 wt%.

Preferably, the composition may be used as such, i.e. in neat form, or may be diluted prior to use. The degree of dilution is generally dependent on market choice. In some markets more concentrated products are required, while in other markets more diluted products are preferred. When the composition is a liquid dishwashing composition, it is typically diluted with water in a weight ratio in the range of from 1:1 to 1:10.

The liquid dishwashing composition may optionally contain ingredients such as fragrances, colorants, suds boosters, and odor absorbing materials.

Multipurpose liquid spray composition

The compositions of the present invention are useful as multipurpose liquid spray compositions comprising nonionic surfactant and 50-90% water. This is typically dispensed from the bottle using a spray pump. These types of multi-purpose liquid spray compositions are useful for cleaning and disinfecting inanimate or animate surfaces. Inanimate surfaces include hard surfaces such as floors, walls, windows, doors, furniture, and desktops in various indoor and outdoor locations. Other types of hard surfaces cleaned by such compositions include articles found in homes, offices, and other public places. These products can also be used to disinfect the local surface of the human or animal body. They are useful as bath water, as water for shaving, cleaning infants between diaper changes, for disinfecting pets and hands in homes, hospitals and medical clinics, and many other personal disinfecting applications.

The multipurpose liquid spray composition may include a stability enhancer as a nonionic surfactant. The nonionic surfactant used in the present invention is preferably selected from the group comprising fatty alcohol ethoxylates, fatty acid ethoxylates, alkylphenol ethoxylates or polyoxyethylene sorbitan alkyl esters. The nonionic surfactant is preferably included in the multipurpose liquid spray composition of the present invention in an amount of from 0.01 to 10%, preferably from 0.1 to 5% by weight of the composition.

The compositions of the present invention may be provided as disinfectant compositions comprising 20-50% C2-C3 alcohol and 45-75% water. Above 60% by weight of the composition, alcohol is one of the most effective antimicrobial compositions along with water. They kill bacteria and viruses almost immediately. However, such a composition with a high alcohol content is caustic on the skin, as it dries out the moisture present on the surface and to some extent below the skin surface. Thus, many people prefer hand sanitizers with low alcohol content. However, 20-50 wt% of the alcohol in the composition does not provide complete antimicrobial protection. In these cases, the present invention comprising an amino acid surfactant and an alkane diol can supplement the antimicrobial activity of the alcohol to provide complete protection. Such hand sanitizers can be contained in vials for sanitizing hands when people travel without the opportunity to use soap and water to clean the hands. Such disinfectants may also be placed at the entrances of buildings such as apartments, homes, offices, restaurants, and public places such as airports, trains, and bus stops. They are particularly useful in hospitals and clinics to minimize the spread of pathogens through hand contact.

Suitable alcohols for inclusion in the disinfectant compositions of the present invention are ethanol, propanol, isopropanol, and combinations thereof. Ethanol is the most preferred alcohol. The composition preferably comprises a combination of ethanol and isopropanol. When ethanol is present, it is preferably included at 25-45% by weight of the composition. When isopropanol is present, it is preferably contained at 1-10% by weight of the composition, preferably 1-5% by weight.

The disinfectant composition may optionally comprise a nonionic surfactant. The nonionic surfactants described above for use in the multipurpose liquid spray compositions are useful in disinfectant compositions.

The disinfectant composition may optionally comprise from 0.01 to 1 wt%, preferably from 0.05 to 0.8 wt%, more preferably from 0.05 to 0.5 wt% of a thickener.

The thickener in the disinfectant composition according to the present invention is preferably selected from the group consisting of homopolymers, copolymers and combinations thereof, wherein the homopolymers and copolymers comprise monomers selected from the group consisting of acrylic acid, acrylic esters, compounds comprising an acrylic ester group and combinations thereof. Most preferred thickeners for disinfectant compositions are those of the carbomer class. In preferred embodiments, the disinfectant composition may comprise from 0 to 15 wt% of optional ingredients, such as chelating agents, colorants, fragrances, skin conditioning agents, vitamins such as vitamin B3, and combinations thereof. The disinfectant composition preferably comprises skin conditioning agents, and these skin conditioning agents are preferably selected from silicones, siloxanes, and combinations thereof. The composition preferably comprises vitamins other than vitamin B3 and these vitamins are preferably selected from vitamin a, vitamin E or a combination thereof. Even more preferably, the composition comprises vitamin E acetate.

The invention will now be illustrated by the following non-limiting examples.

Examples

Examples A-J,1-6 effects of compositions outside the present invention on antimicrobial efficacy compared to compositions within the present invention:

the following compositions shown in Table-1 below were prepared.

Table-1:

the antimicrobial efficacy of the above compositions against staphylococcus aureus (s.aureus) and enterococcus hainanensis (e.hirae) was tested using the procedure given below.

European Standard EN1276 (quantitative suspension test for evaluating the bactericidal activity of chemical disinfectants and preservatives used in food, industrial, household and institutional areas) was used to measure log kill.

Data on bacterial efficacy in log kill at 5 minutes exposure to various compositions is given in table 2 below:

TABLE-2

Examples	Staphylococcus aureus, log kill	Enterococcus hai log kill
			A	2.1	1.3
B	0.2	0.5
			1	5.0	5.0
C	0.5	0.3
			2	>5	>5
D	3.1	3.0
			E	0.3	0.4
3	>5	>5
			F	4.6	3.5
G	1.8	1.8
			4	>5	>5
H	0.5	0.1
			I	0.1	0.5
5	1.5	0.6
			J	0.7	-
6	3.1	-

In the above table, >5log kill means that starting from 10 ⁷ bacteria, a "no growth" of bacteria was observed after 5 minutes of treatment with the composition (indicating almost complete kill of bacteria).

The data in table 2 above show that the compositions according to the invention (examples 1 to 6) provide synergistic antimicrobial killing over a contact time of 5 minutes compared to the killing provided by the individual components (examples a to J).

Claims

1. An antimicrobial composition comprising

(i) 0.01 to 2 wt % of an amino acid based surfactant having a pKa value in the range of 3 to 5;

(ii) 0.05 to 2 wt. % of a C3-C9 alkane diol;

wherein the composition has a pH in the range of 2.5 to 4.5.

2. The composition of claim 1, wherein the amino acid surfactant is selected from one or more of sodium lauroyl sarcosinate, sodium oleoyl sarcosinate, sodium oleoyl glutamate, sodium oleoyl glycinate, disodium cocoyl glutamate, sodium cocoyl glutamate, disodium lauroyl glutamate, sodium cocoyl glycinate and sodium lauroyl glycinate.

3. The composition of claim 1 or 2, wherein the alkane diol is selected from one or more of propylene glycol, hexylene glycol or octanediol.

4. A composition as claimed in any preceding claim comprising 0.02-1 wt% of an amino acid based surfactant.

5. A composition as claimed in any preceding claim comprising an organic acid.

6. The composition of claim 5, wherein the organic acid is selected from one or more of lactic acid, glycolic acid, tartaric acid and citric acid; preferably citric acid.

7. A composition as claimed in claim 5 or 6, wherein the organic acid comprises 0.1 to 5% by weight of the composition.

8. A composition as claimed in any one of the preceding claims 1 to 7 which is a liquid laundry detergent composition additionally comprising from 1 to 30 wt% of anionic surfactant.

9. A composition as claimed in any one of the preceding claims 1 to 7 which is a liquid dishwashing composition additionally comprising from 1 to 30 wt% of anionic surfactant and from 0.1 to 5 wt% of amphoteric surfactant.

10. A composition as claimed in any one of the preceding claims 1 to 7 which is a multi-purpose liquid spray composition comprising a nonionic surfactant and 50 to 90% water.

11. A composition as claimed in any one of the preceding claims 1 to 7 which is a disinfectant composition further comprising 20 to 50% of a C2-C3 alcohol and 45 to 75% of water.