Skin cleansing composition

Abstract

The present invention relates to a skin cleansing composition, in particular a skin cleansing composition that provides improved antimicrobial benefits. The skin cleansing composition comprises an N-acyl (R-C = O) substituted diamine wherein R is an alkyl group of 1 to 8, preferably 1 to 4 linear or branched carbon atoms; and wherein the pH of the composition is in the range of from 4 to 11; and the composition is substantially free of bleaching agents.

Description

[0001] Invention Field This invention relates to a skin cleansing composition. In particular, this invention relates to a skin cleansing composition that provides improved antimicrobial benefits, especially in compositions that are substantially free of bleach. Background of the Invention Microorganisms (e.g., bacteria) tend to colonize surfaces (e.g., human skin). Some of these microorganisms can cause harmful effects if they enter the human system (e.g., through cuts in the skin and through ingestion). Therefore, it is generally desirable to maintain hygiene by eliminating these harmful microorganisms. For example, people tend to wash their hands from time to time with skin-cleaning compositions to help maintain hygiene.

[0003] Several skin cleansing compositions that provide antimicrobial benefits are known in the art, such as hand sanitizer / body wash compositions. These skin cleansing compositions are available in solid form (e.g., bars such as soap bars) and in liquid form (e.g., liquid hand sanitizer / body wash). Typically, the antimicrobial benefits provided by these skin cleansing compositions are provided by one or more active substances that may be present in them. For example, skin cleansing compositions containing antibacterial active substances are known in the art. Bleaching agents such as peroxides also provide good antibacterial efficacy. Peroxides and similar bleaching agents are generally oxidizing agents, which are considered by many to be caustic to the skin.

[0004] Given the above, there is a tendency to expect newer technologies that offer improved antimicrobial benefits while remaining gentle on the skin. Therefore, providing gentle skin-cleansing compositions that offer improved antimicrobial benefits remains a topic of interest.

[0005] It has been found that N-acyl-substituted diamines provide antimicrobial benefits when included in skin cleansing compositions with a selected pH. N-acyl-substituted diamine compounds such as tetraacetylethylenediamine (TAED) are known and widely used as bleach activators in laundry detergent compositions containing bleach. These bleach activators are typically included in laundry detergent compositions along with bleaching agents such as peroxides.

[0006] WO2016 / 204943 (The Dial Corp) discloses a cosmetic, detergent, and surface cleaning composition comprising the biosurfactant flavolipid, which is considered milder compared to conventional detergent active ingredients. It also discloses that bleaching agents such as percarbonates can be used in detergent compositions in conjunction with bleaching activators such as TAED.

[0007] CN106281757 discloses a broad-spectrum antibacterial liquid detergent, which is composed of the following components in parts by weight: 35 parts of 50% sodium C12 alkylbenzene sulfonate solution; 2 parts of traditional Chinese medicine; 10 parts of polyethylene glycol; 6 parts of tetraacetyl ethylenediamine; 15 parts of fatty polyethylene ether; 1 part of trisodium phosphate; 1 part of polystyrene latex; 0.02 parts of fragrance; 0.06 parts of citric acid; 0.02 parts of pigment; and 70 parts of water.

[0008] This invention relates to skin cleansing compositions that are substantially free of bleach but still achieve high antimicrobial efficacy. This is achieved by using an N-acyl-substituted diamine compound in the absence of bleach. This antimicrobial effect is further improved when the N-acyl-substituted amine is combined with a selected potassium salt. Invention Overview In a first aspect, the present invention relates to a skin cleansing composition comprising 0.1 to 4% by weight of an N-acyl (RC=O)-substituted diamine, wherein R is an alkyl group having 1 to 8 straight-chain or branched carbon atoms; and wherein the pH of the composition is in the range of 4 to 11. The composition contains virtually no bleach.

[0010] In a second aspect, the present invention relates to a method for providing antimicrobial benefits to a surface, comprising the following steps: a. Applying the composition of the first aspect to the surface; and b. Rinse the surface within 5 minutes of performing step a.

[0011] In a third aspect, the present invention relates to the use of the composition of the first aspect for obtaining antimicrobial benefits. Invention Details Any feature of one aspect of the invention may be used in any other aspect of the invention. The word “comprising” is intended to mean “including”, but not necessarily “consisting of” or “made up of”. In other words, the listed steps or options need not be exhaustive. Except where explicitly stated in the operational and comparative examples, or elsewhere, all figures indicating the amount of material or reaction conditions, physical properties of the material, and / or uses herein should be understood to be modified by the word “about”. Numerical ranges expressed in the format “from x to y” are understood to include both x and y. When multiple preferred ranges are described in the format “from x to y” for a particular feature, it should be understood that all ranges combining different endpoints are also considered. Unless otherwise stated, quantities used herein are expressed as a weight percentage based on the total weight of the composition and may be abbreviated as “weight%”. The use of any and all instances or exemplary language (e.g., “as”) provided herein is merely for the purpose of better illustrating the invention and is not intended to limit the scope of the invention in any way.

[0013] For the purposes of this invention, the terms "antimicrobial benefit," "antimicrobial effect," or "antimicrobial efficacy" are used interchangeably and have the same meaning. Preferably, "antimicrobial benefit," "antimicrobial effect," or "antimicrobial efficacy" refers to a reduction in the number of microorganisms (e.g., bacteria, fungi, and viruses). This antimicrobial effect is obtained when the composition of the invention is preferably applied to a surface that may be inanimate or animate; and the surface is rinsed within 5 minutes of the application of the composition. More preferably, the composition is applied to a animate substrate, such as human skin. As used herein, "skin" preferably refers to skin on any part of the body, such as the face, neck, chest, back, arms, armpits, hands, legs, buttocks, and scalp.

[0014] The skin cleanser is essentially free of bleach. Therefore, the composition preferably contains less than 1% by weight, more preferably less than 0.1% by weight, even more preferably less than 0.05% by weight, and even more preferably less than 0.01% by weight of bleach. More preferably, the bleach is present only in a technically irrelevant amount, and ideally, the bleach is not present in the composition.

[0015] Bleach is a compound that produces a bleaching effect on a surface. These agents are typically chlorine or peroxide-type, preferably peroxide-type. Peroxide-type bleach refers to bleach containing a hydrogen peroxide source. This class of compounds includes perborates, percarbonates, peracids, and persulfates. They can also be persilicates or perphosphates. Bleach is typically an alkali metal salt, preferably a sodium salt.

[0016] The skin cleansing composition (composition) according to the invention comprises 0.1 to 4% by weight of an N-acyl (RC=O) substituted diamine, wherein R is an alkyl group having 1 to 8 straight-chain or branched carbon atoms; and wherein the pH of the composition is in the range of 4 to 11; and wherein the composition is substantially free of bleach.

[0017] When applied to a surface (living or non-living, preferably living), the composition provides an antimicrobial effect. Preferably, the antimicrobial effect is achieved within a timeframe of at least 5 minutes, such as 1 minute, 30 seconds, and 15 seconds.

[0018] N-acyl-substituted diamine The composition comprises an N-acyl (RC=O)-substituted diamine, wherein R is a straight-chain or branched alkyl group, consisting of 1 to 8, preferably 1 to 4 carbon atoms. Examples of N-acyl-substituted diamines suitable for use in this invention include tetraacetylethylenediamine (TAED), triacetylethylenediamine, diacetylethylenediamine (DAED), and mixtures thereof. Preferably, the N-acyl-substituted diamine is non-volatile.

[0019] The composition contains 0.1 to 4% by weight, preferably 0.5 to 3% by weight, of an N-acyl-substituted diamine.

[0020] It has been found that N-acyl-substituted diamines provide antimicrobial benefits when used in skin cleansing compositions with pH values ​​of 4 to 11.

[0021] Potassium salts Preferably, the composition further comprises a potassium salt selected from potassium chloride, potassium sulfate, potassium nitrate, potassium sorbate, potassium carbonate, potassium acetate, potassium hydrogen phosphate, potassium salts of fatty acids having 8 to 22 carbon atoms, and mixtures thereof. More preferably, the potassium salt is selected from potassium chloride, potassium sulfate, potassium nitrate, and potassium salts of fatty acids having 8 to 22 carbon atoms, and mixtures thereof. Examples of potassium salts of fatty acids having 8 to 22 carbon atoms include potassium laurate, potassium myristate, potassium palmitate, and potassium stearate. Even more preferably, the potassium salt is selected from potassium chloride, potassium sulfate, and potassium laurate, and mixtures thereof.

[0022] Preferably, the composition contains 0.1 to 15% by weight, more preferably 1 to 13% by weight, even more preferably 2 to 12% by weight, further more preferably 3 to 10% by weight, and even more preferably 5 to 8% by weight of potassium salt.

[0023] It has been found that when potassium salts are used in combination with the aforementioned N-acyl-substituted diamines, improved antimicrobial benefits are obtained.

[0024] surfactants Preferably, the composition further comprises a surfactant. Preferably, the surfactant is selected from anionic surfactants, nonionic surfactants, cationic surfactants, amphoteric surfactants, and mixtures thereof. More preferably, the surfactant is selected from anionic surfactants, amphoteric surfactants, and mixtures thereof. Even more preferably, the surfactant is anionic. A preferred anionic surfactant is a soap.

[0025] Anionic surfactants Preferably, the selected anionic surfactant is selected from one or more synthetic anionic surfactants. Preferably, the synthetic anionic surfactant is selected from alkyl sulfates (AS), alkyl ether sulfates (AES), α-olefin sulfonates (AOS), and mixtures thereof. Examples of ASs that can be used as anionic surfactants in the composition include sodium lauryl sulfate (SLS), sodium myristyl sulfate, sodium palmitate sulfate, and mixtures thereof. Examples of AESs that can be used as anionic surfactants include anionic surfactants having the following general formula: R1-(OR') n -O-SO3- M + ,in: R1 is a saturated or unsaturated C8-C. 16 C is preferred 12 -C 14 Alkyl chain; preferably, R1 is a saturated C8-C chain. 16 More preferably saturated C 12 -C 14 Alkyl chain; R' is ethylene; n is 1 to 18; preferably 1 to 15, more preferably 1 to 10, even more preferably 1 to 5, and even more preferably 1 to 3. M + It is a suitable cation that provides electrical neutrality, preferably sodium, calcium, potassium or magnesium, more preferably sodium cation.

[0026] Examples of AES that can be used as anionic surfactants in compositions include sodium lauryl ether sulfate (SLES), sodium myristyl ether sulfate, and sodium palmityl ether sulfate, and mixtures thereof. Preferred AES are SLES having 1 to 3 ethylene oxide units per molecule. More preferably, SLES have 1 to 2 ethylene oxide units per molecule.

[0027] Optionally, but preferably, the anionic surfactant may be selected from sodium salts of fatty acids having 8 to 22 carbon atoms, such as sodium lauryl ester, sodium myristate, sodium palmitate, sodium stearate, and mixtures thereof.

[0028] It should be understood that, if used, the potassium salt of a fatty acid having 8 to 22 carbon atoms is used as the potassium salt in the composition, i.e., it is not used as a soap. In other words, if a potassium salt of a fatty acid having 8 to 22 carbon atoms, such as potassium laurate, is used in the composition, the anionic surfactant can be selected from synthetic anionic surfactants or from non-potassium salts of fatty acids having 8 to 22 carbon atoms or mixtures thereof, as described above. In other words, according to the present invention, the term "soap" is used to refer to any soap other than potassium laurate.

[0029] Nonionic surfactants Preferably, the nonionic surfactant can be selected from: - Fatty alcohol ethoxylates with saturated carbon chains and HLB values ​​higher than 15.5, such as Brij ® 35 (also known as Brij) ® L23), - Ethoxylated fatty alcohols with unsaturated carbon chains and an HLB greater than 12, such as Brij ® 97 and Brij ® 99, - Alkylphenol ethoxylates with an HLB greater than 15; for example, Triton TM X 405, - Polyoxyethylene dehydrated sorbitan alkyl ester, having a saturated C12 to C16 carbon chain and an HLB greater than 12; for example, Tween ® 20, - Polyoxyethylene dehydrated sorbitan alkyl esters having an unsaturated C18 carbon chain and an HLB greater than 9; for example, Tween ® 80. Tween ® 81; and Tween ® 85; and its mixtures.

[0030] Amphoteric surfactants When added to the composition, the amphoteric surfactant provides improved foaming. Preferably, the amphoteric surfactant is selected from cocamidopropyl betaine (CAPB), cocamidopropyl alcohol amide (CMEA), cocamidopropyl acetate, and mixtures thereof.

[0031] cationic surfactants Preferably, the cationic surfactant can be selected from hexadecyltrimethylammonium chloride, dodecyltrimethylammonium chloride, hexadecylpyridine chloride, tetramethylammonium chloride, tetraethylammonium chloride, octyltrimethylammonium chloride, dodecyltrimethylammonium chloride, hexadecyltrimethylammonium chloride, octyldimethylbenzylammonium chloride, decyldimethylbenzylammonium chloride, stearyldimethylbenzylammonium chloride, didodecyldimethylammonium chloride, dioctadecyldimethylammonium chloride, tallow trimethylammonium chloride, dihydrotallow dimethylammonium chloride (e.g., Arquad 2HT / 75 from Akzo Nobel), cocotrimethylammonium chloride, PEG-2-oleoylammonium chloride, and their corresponding hydroxides. Other suitable cationic surfactants include those designated by CTFA as Quaternium-5, Quaternium-31, and Quaternium-18. Mixtures of any of the foregoing substances may also be suitable. A particularly useful cationic surfactant is hexadecyltrimethylammonium chloride, which is commercially available, for example, as GENAMIN. ® CTAC. Another particularly useful cationic surfactant is docosyltrimethylammonium chloride, which is commercially available, for example, as GENAMIN. ® KDMP. Another preferred cationic surfactant is stearamidopropyl dimethylamine.

[0032] The composition contains 1 to 85% by weight of surfactant, preferably 5 to 80% by weight, more preferably 10 to 75% by weight, even more preferably 15 to 70% by weight, even more preferably 25 to 66% by weight, even more preferably 35 to 60% by weight, and even more preferably 40 to 55% by weight of surfactant.

[0033] pH The pH of the composition is in the range of 4 to 11, preferably 4.5 to 10.5, even more preferably 5.0 to 10.0, further more preferably 5.5 to 9.5, even more preferably 6.0 to 9.0, even more preferably 6.5 to 8.5, and even more preferably 7.0 to 8.0. For example, the pH of the composition can be in the range of 9.6 to 10.2. Suitable pH adjusters, such as sodium hydroxide and sodium bicarbonate, can be used to adjust the pH of the composition.

[0034] If the composition is in liquid form, the pH of the composition is preferably in the range of 4 to 11 when measured at 25 to 35°C before dilution or preferably after dilution to a 50% concentration.

[0035] If the composition is in solid form, the pH of the composition is preferably in the range of 4 to 11 when measured at a temperature of 25 to 35°C using a 1 to 8% (e.g., 8%) aqueous solution of the composition in demineralized water. The pH range described above is generally considered to be skin-friendly.

[0036] Forms of the composition Preferably, the composition is in liquid or solid form. More preferably, the composition is in solid form, for example, in bars. Even more preferably, the composition is in the form of soap bars.

[0037] Therefore, the composition is preferably a liquid skin cleansing composition comprising 0.1 to 15% by weight of an N-acyl (RC=O) substituted diamine, wherein R is 1 to 8, preferably 1 to 4, straight-chain or branched carbon atoms of an alkyl group; and wherein the pH of the composition is in the range of 4 to 11, preferably 4 to 7.

[0038] Optionally, but preferably, the composition is a solid skin cleansing composition comprising 0.1 to 15% by weight of an N-acyl (RC=O)-substituted diamine, wherein R is 1 to 8, preferably 1 to 4, straight-chain or branched alkyl groups; and wherein the pH of the composition is in the range of 4 to 11.

[0039] More preferably, the composition is a soap bar composition comprising 0.1 to 15% by weight of an N-acyl (RC=O) substituted diamine, wherein R is 1 to 8, preferably 1 to 4, straight-chain or branched alkyl groups; and wherein the pH of the composition is in the range of 8 to 11.

[0040] More preferably, the composition is a soap bar composition comprising: -0.1 to 15% by weight of an N-acyl-substituted diamine selected from diacetylethylenediamine, tetraacetylethylenediamine, and mixtures thereof; and -0.1 to 15% by weight of one or more of the above potassium salts, The pH value of the composition is in the range of 8 to 11.

[0041] In this case, one or more anionic surfactants in the composition are preferably selected from synthetic anionic surfactants or non-potassium salts of fatty acids having 8 to 22 carbon atoms, such as sodium laurylate, sodium myristate, sodium palmitate, and sodium stearate.

[0042] Structured agents Preferably, the composition comprises a structuring agent. Preferably, the structuring agent is selected from silica, talc, calcite, pumice, tricalcium phosphate, chalk, bleaching clay, kaolin, starch, gum, colloidal silica, sodium polyacrylate, tetraalkyl and / or trialkylarylammonium chlorothiazene, chemically modified magnesium aluminum silicate, organically modified montmorillonite clay, hydrated aluminum silicate, fumed silica, carboxyvinyl polymers, sodium carboxymethyl cellulose, ethylene glycol monostearate, and mixtures thereof.

[0043] Talc is a magnesium silicate mineral material with a platy silicate structure and Mg3Si4(OH). 22 It is composed of substances that can be obtained in a hydrated form. It has a plate-like morphology and is essentially oleophilic / hydrophobic, meaning it is wetted by oil rather than water.

[0044] Starch can be used directly or modified during the preparation of the strip composition to make it gelatinized, partially or completely gelatinized. Another suitable starch is pregelatinized starch, which is gelatinized before being added as an ingredient to the strip composition of the present invention. Various forms of gelatinization at different temperatures are available, for example, cold water-dispersible starch. An example of commercially available pregelatinized starch is farmal. ® CS 3400.

[0045] Preferably, the composition contains 1 to 50% by weight, more preferably 3 to 45% by weight, even more preferably 10 to 30% by weight, and even more preferably 15 to 25% by weight of a structuring agent.

[0046] polymer Preferably, the composition further comprises a water-soluble polymer. Preferably, such polymer is selected from polyvinyl alcohol, polyvinylpyrrolidone, sodium carboxymethyl cellulose, polyethylene glycol, methyl cellulose, hydroxypropyl methyl cellulose, and mixtures thereof.

[0047] Preferably, the composition contains 1 to 20% by weight, more preferably 3 to 17% by weight, even more preferably 5 to 15% by weight, further more preferably 7 to 13% by weight, and still more preferably 9 to 12% by weight of a water-soluble polymer.

[0048] This polymer can be added to a mixture of compositions or used to coat a composition. For example, if the composition is in the form of a strip or tablet, these polymers can form a water-soluble coating on such a strip or tablet.

[0049] If the composition is formulated into bars, it preferably contains a polyol (also called a polyhydric alcohol) or a mixture of polyols. A polyol is the term used herein to refer to a compound having multiple hydroxyl groups (at least two, preferably at least three), which is highly water-soluble, preferably readily soluble in water. Many types of polyols are available, including relatively low molecular weight short-chain polyhydroxy compounds such as glycerol and propylene glycol; sugars such as sorbitol, mannitol, sucrose, and glucose; modified carbohydrates such as hydrolyzed starch, dextrin, and maltodextrin; and polymerized synthetic polyols such as polyalkylene glycols, for example, polyoxyethylene glycol (PEG) and polypropylene glycol (PPG). Particularly preferred polyols are glycerol, sorbitol, and mixtures thereof. The most preferred polyol is glycerol. If the composition is formulated into bars, it preferably contains 0 to 8% by weight, more preferably 1 to 7.5% by weight, and even more preferably 2 to 5% by weight of a polyol.

[0050] Preferably, the composition further comprises a light-blocking agent. Examples of light-blocking agents include titanium dioxide, zinc oxide, etc. An optional light-blocking agent is zinc stearate.

[0051] The preferred formulation may additionally contain up to 30% by weight of beneficial agents. Preferred beneficial agents include moisturizers, emollients, sunscreens, and anti-aging compounds. These agents may be added at appropriate steps during the preparation of the composition.

[0052] The composition may further comprise one or more of the following components: The composition may preferably further comprise a skin whitening agent selected from ammonium lactate, arbutin, azelaic acid, kojic acid, butylated hydroxyanisole, butylated hydroxytoluene, citrate, 3-diphenylpropane derivatives, ellagic acid, glucono-1-ascorbic acid ester, gluconic acid, glycolic acid, hydroquinone, 4-hydroxyanisole, linoleic acid, magnesium ascorbate phosphate, 2,4-resorcinol derivatives, 3,5-resorcinol derivatives, vitamins such as vitamin B6, vitamin B12, vitamin C, vitamin A, resorcinol derivatives, and mixtures thereof.

[0053] If the composition is formulated into a bar, it preferably contains 10 to 20% by weight, more preferably 14 to 18% by weight of water. Alternatively, if the composition is formulated into a liquid form, it preferably contains 40 to 90% by weight of water, more preferably 60 to 85% by weight of water.

[0054] The composition may preferably further comprise a preservative to protect it against the growth of potentially harmful microorganisms. Particularly preferred preservatives include hydantoin derivatives, propionates, various quaternary ammonium compounds, phenoxyethanol, imidazolidinyl urea, sodium dehydroacetate, and benzyl alcohol. Preferably, the preservative is used in an amount ranging from 0.01% to 2% by weight.

[0055] Diluents other than water can include liquid or solid emollients, solvents, humectants, thickeners, and powders. Examples of each of these types of mediators, which can be used alone or as a mixture of one or more mediators, are as follows: Emollients such as stearyl alcohol, glyceryl monoricinoleate, mink oil, cetyl alcohol, isopropyl isostearate, stearic acid, isobutyl palmitate, isocetyl stearate, oleyl alcohol, isopropyl laurate, hexyl laurate, decyl oleate, octadecane-2-ol, isocetyl alcohol, eicosanol, behenyl alcohol, cetyl palmitate, silicone oils such as dimethyl polysiloxane, di-n-butyl sebate, isopropyl myristate, isopropyl palmitate, isopropyl stearate, butyl stearate Esters, polyethylene glycol, triethylene glycol, lanolin, cocoa butter, corn oil, cottonseed oil, olive oil, palm kernel oil, rapeseed oil, safflower seed oil, evening primrose oil, soybean oil, sunflower seed oil, avocado oil, sesame oil, coconut oil, peanut oil, castor oil, acetylated lanolin alcohol, petrolatum, mineral oil, butyl myristate, isostearic acid, palmitic acid, isopropyl linoleate, lauryl lactate, myristyl lactate, decyl oleate, myristyl myristate.

[0056] In addition, the composition preferably contains other optional ingredients, such as antioxidants, fragrances, polymers, chelating agents, colorants, deodorants, dyes, emollients, moisturizers, enzymes, foam promoters, foaming agents, skin conditioning agents, pH adjusters, and stabilizers, which may be added in suitable amounts. Preferably, these ingredients are added after the saponification step. Preferably, sodium metabisulfite, ethylenediaminetetraacetic acid (EDTA), borax, or ethylenedihydroxybisphosphonic acid (EHDP) are added to the formulation. The amount of these ingredients in the composition may be 0 to 7% by weight, more preferably 1 to 5% by weight, and even more preferably 2 to 4% by weight.

[0057] In a second aspect, the present invention relates to a method for providing antimicrobial benefits, comprising the following steps: a. Applying the composition according to the first aspect to a surface; and b. Rinse the surface within 5 minutes of performing step a.

[0058] Step a includes applying the composition of the first aspect to a surface. The surface is preferably a non-living or living surface. More preferably, the surface is a living surface, such as human skin. As used herein, "skin" preferably refers to skin on any part of the body, such as the face, neck, chest, back, arms, armpits, hands, legs, buttocks, and scalp. Step a is preferably performed in which the user applies the composition of the first aspect to the surface along with an amount of water sufficient to produce foam.

[0059] The method includes an additional step, step b, in which the surface to which the composition is applied is rinsed with water to remove the composition from the surface. Step (b) is performed within less than 5 minutes, more preferably less than 3 minutes, even more preferably less than 1 minute, and further preferably less than 35 seconds, for example, 10 to 30 seconds, after step a. When the method is performed as described in the second aspect, an antimicrobial benefit is obtained, namely, a reduction in microorganisms (e.g., bacteria) from the surface to which the composition is thus applied. Preferably, the method is inherently non-therapeutic and / or cosmetic.

[0060] In a third aspect, the present invention relates to the use of the composition of the first aspect for obtaining antimicrobial benefits. Preferably, the use is non-therapeutic.

[0061] In a fourth aspect, the present invention relates to the use of N-acyl-substituted diamines in substantially bleach-free compositions for obtaining antimicrobial benefits, wherein the pH of the composition is in the range of 4 to 11. Preferably, the use is non-therapeutic.

[0062] In a fifth aspect, the present invention relates to the use of a combination of an N-acyl-substituted diamine and a potassium salt in a substantially bleach-free composition in the pH range of 4 to 11 for obtaining antimicrobial benefits. Preferably, the use is non-therapeutic.

[0063] The invention is further described through the following non-limiting embodiments: Example Experimental protocol The skin cleansing compositions in the form of soap bars (as shown in Table 2) are prepared as follows: Soap strips are prepared using oils, such as palm oil (PO) and palm kernel oil (PKO) in the desired ratio (e.g., 80:20; PO:PKO), through saponification and processing with water, glycerol, electrolytes such as sodium chloride, preservatives such as EDTA, EHDP, and / or fillers into strips (as shown in Table 1). Alternatively, soap strips can be prepared using, for example, PO:PKO ratios of 70:30, 85:15, or 90:10. Saponification is carried out via a spiral agitator, a continuous saponification tank, or a plow shear mixer. The final material is cooled and extruded into soap strips. These soap strips, having the desired PKO values ​​(10, 20, 25, 30, and 40) and an IV (iodine value) ranging from 30 to 45, are manufactured internally.

[0064] Soap bars are pulverized in a Sigma mixer for up to 5 minutes. After the bars are completely pulverized, solid ingredients such as soda ash and talc are added and mixed. Active ingredients such as TAED are added at this stage and mixed, followed by the polymer and colorant (if desired), and mixed for up to 3 minutes. Alternatively, the colorant can be added during the bar pulverization process. Finally, fragrance is added and mixed for up to 3 minutes. After this mixing, the material is processed through a three-roll mill and pressed into bars using a bar press, and then stamped as needed.

[0065] Antibacterial effect: The antimicrobial efficacy of the compositions listed in Table 2 below was evaluated using ASTM 2783, a standard test method for evaluating the antimicrobial activity of water-miscible compounds using a time-killing procedure. *Escherichia coli* (ATCC 10536) and *Staphylococcus aureus* (ATCC 6538) were used as test organisms.

[0066] Preparation of working cultures for the test organism: Approximately 48 hours before the test, sterile trypsin-soy broth (TSB) tubes were inoculated from stock glycerol containing the challenge (test) microorganism. The broth culture was incubated at 35±2°C for 24 hours. Approximately 24 hours before the test, the broth culture was inoculated onto sterile trypsin-soy agar (TSA) surfaces and incubated at 35±2°C for approximately 24 hours.

[0067] Suspension bacterial challenge test and suspension validation test (prepared just before use): Prepare a suspension of the challenge microorganism in sterile 0.9% saline and adjust the optical density at 620 nm to obtain approximately 7 × 10⁻⁶. 8 cfu / mL up to 9×10 8 The challenge suspension concentration was determined by diluting the challenge microorganisms in sterile saline to prepare a neutralization challenge test suspension containing approximately 3000–10000 cfu / mL. The challenge suspension was prepared by diluting the challenge microorganisms in sterile saline.

[0068] Preparation of 8% soap paste: Finely grind the soap bar sample and weigh 8 g into a sterile bottle. Preheat 92 mL of sterile distilled water (DW) at 50±1℃, add 8 g of the soap sample, and mix using a submersible magnetic stirrer for 25 to 30 minutes to prepare an 8% soap slurry. After 25 to 30 minutes, transfer 10 mL portions of the sample to vials placed at 40±1℃, maintain for 3 to 5 minutes to reach equilibrium, and mix using a submersible magnetic stirrer.

[0069] Evaluation of bacterial reduction efficacy: Place 10 mL of the test solution in a vial and incubate in a water bath to maintain the test temperature for 3 to 5 minutes to equilibrate. Transfer 0.1 mL of the challenge suspension to the vial containing the test solution and mix thoroughly using a submersible magnetic stirrer. Using a calibrated minute and second timer, expose the challenge suspension to the test solution for the required contact time, e.g., less than 5 minutes, e.g., 30 seconds. After the contact time has elapsed, transfer 1 mL of the sample aliquot from the vial containing the test solution / challenge suspension to a test tube containing 9.0 mL of pre-validated neutralizing agent and mix thoroughly using a vortex mixer. Prepare an additional 10-fold dilution (10 mL of test solution) by transferring 1 mL of the sample aliquot to 9 mL of neutralizing agent. -2 10 -3 10 -4 and 10 -5 Using TSA to 10 -1 Up to 10 -5 Each diluted 1.0 mL aliquot was inoculated in duplicate using the pour plate technique. The plates were incubated under the given incubation conditions.

[0070] The logarithmic reduction in each challenge suspension at each timed exposure, attributable to the test solution, is calculated as follows: Log 10 Decrease = Log 10 Average (NC) - Log 10Average (Pex) Where NC = population control CFU / mL, and Pex = post-exposure population CFU / mL Table 1: Composition of the thin strips

[0071] Table 2: Soap bars and the obtained antimicrobial effects The antimicrobial effects obtained using the compositions according to the invention (Examples 1 to 8) and controls (A and B) are summarized below:

[0072] # Polymers, colorants, and fragrances; Staphylococcus aureus ATCC 6538; contact time = 30 seconds.

Claims

1. A skin cleansing composition comprising 0.1 to 4% by weight of an N-acyl (RC=O)-substituted diamine, wherein R is an alkyl group having 1 to 8 straight-chain or branched carbon atoms; and wherein the pH of the composition is in the range of 4 to 11; The composition described herein is substantially free of bleach.

2. The composition of claim 1, wherein the N-acyl-substituted diamine is selected from diacetylethylenediamine, triacetylethylenediamine, tetraacetylethylenediamine, and mixtures thereof.

3. The composition of any one of claims 1 or 2, wherein the N-acyl-substituted diamine is tetraacetylethylenediamine.

4. The composition according to any one of claims 1 to 3, wherein the composition further comprises 0.1 to 15% by weight of a potassium salt.

5. The composition of claim 4, wherein the potassium salt is selected from potassium chloride, potassium sulfate, potassium nitrate, potassium sorbate, potassium carbonate, potassium acetate, potassium hydrogen phosphate, potassium salts of fatty acids having 8 to 22 carbon atoms, and mixtures thereof.

6. The composition of claim 5, wherein the potassium salt is selected from potassium chloride, potassium sulfate, potassium nitrate, and potassium salts of fatty acids having 8 to 22 carbon atoms, and mixtures thereof.

7. The composition of claim 6, wherein the potassium salt is selected from potassium chloride, potassium sulfate, and potassium laurate and mixtures thereof.

8. The composition of any one of claims 1 to 7, wherein the composition further comprises 1 to 85% by weight of a surfactant.

9. The composition of claim 8, wherein the surfactant is soap.

10. The composition of any one of claims 1 to 9, wherein the pH of the composition is in the range of 8 to 10.

11. The composition according to any one of claims 1 to 10, wherein the composition is in solid form.

12. A method for providing antimicrobial benefits to a surface, comprising the steps of: a. Applying the composition according to any one of claims 1 to 11 to the surface; and b. Rinse the surface within 5 minutes of performing step a.

13. Use of the composition according to any one of claims 1 to 11 for obtaining antimicrobial benefits.

14. Use of N-acyl-substituted diamines in substantially bleach-free compositions for obtaining antimicrobial benefits, wherein the pH of the compositions is in the range of 4 to 11.

15. Use of a combination of an N-acyl-substituted diamine and a potassium salt in a substantially bleach-free composition for obtaining antimicrobial benefits, wherein the pH of the composition is in the range of 4 to 11.

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