Liquid compositions with enhanced antimicrobial activity

Abstract

The present invention relates to a mild liquid composition with enhanced antimicrobial activity. The liquid composition of the present invention is mild and, unexpectedly, exhibits excellent antimicrobial activity when used in cleansing applications. The liquid composition comprises an anionic surfactant and an acid and is formulated to produce a cleaning solution having a pH of 2.9 to 5.2.

Description

[Technical field]

[0001] The present invention relates to a mild liquid composition with enhanced antimicrobial activity. In particular, the liquid composition of the present invention is mild and unexpectedly exhibits excellent antimicrobial activity when used in cleansing applications. The liquid composition comprises an anionic surfactant and an acid and is formulated to produce a cleaning solution with a pH of 2.9 to 5.2. Such liquid compositions can be produced by conventional blending techniques and can be formulated substantially free or free of ethanol, parabens, formaldehyde donors, silicones, sulfates, glycinates and / or halogenated antimicrobial actives. [Background technology]

[0002] Cleansing compositions, such as bars and liquids, are known to have many benefits for consumers who use them. In general, bacteria accumulate on hands, hair, clothes and hard surfaces and can be transmitted from person to person or from object to person through the air and / or daily and normal contact. For example, once on the hands, consumers constantly touch their eyes, nose and mouth, so infection by bacteria is inevitable, causing many diseases such as respiratory and digestive diseases. The Centers for Disease Control reports that washing hands with soap removes bacteria much more effectively than water alone, reducing the chances of catching common illnesses such as diarrhea and colds. In fact, regular use of cleansing compositions reduces the amount of antibiotics people use, making antibiotics less likely to be effective for those who need them.

[0003] Furthermore, cleansing compositions traditionally have biocidal activity against many gram-negative bacteria, and the biocidal activity of cleaning compositions against gram-negative and gram-positive bacteria is fairly limited, especially when the compositions are substantially free of soaps, sulfates, and halogenated actives and are formulated to be very mild on the skin. Summary of the Invention [Problem to be solved by the invention]

[0004] There is an increasing interest in developing liquid compositions that exhibit mild and excellent antimicrobial activity when applied to skin, hair, clothing, hard surfaces, etc. Accordingly, the present invention relates to liquid compositions that exhibit unexpectedly excellent antimicrobial activity when used in cleansing applications. The liquid compositions include an anionic surfactant and an acid, and are formulated to produce or create a cleaning solution having a pH of 2.9 to 5.2. Such compositions can be produced by conventional blending techniques and can also be formulated to be substantially free or free of ethanol, parabens, formaldehyde donors, silicones, sulfates, glycinates, and / or halogenated antimicrobial actives.

[0005] Additional Information Efforts to produce antibacterial soap bars have been disclosed. US Patent No. 6,794,344 describes a soap-based bar composition containing 50% soap with an alkyl chain length of 8 to 10 carbon atoms.

[0006] Other approaches to creating soap-based formulations have also been disclosed: US Patent Application Publication No. 2010 / 0098776 discloses soap-based liquid cleansing formulations with enhanced deposition of conditioning agents and / or skin appearance improving agents.

[0007] Other approaches to producing soap bar compositions have also been disclosed. WO16024090A1 describes a translucent soap bar composition with antibacterial properties.

[0008] Other approaches to producing antibacterial formulations have also been disclosed: US Patent No. 11,110,048 describes topical antiseptic formulations containing quaternary ammonium salts.

[0009] None of the additional information describes a liquid composition having enhanced antimicrobial activity as claimed herein. [Means for solving the problem]

[0010] In a first aspect, the present invention provides a method for producing a composition comprising the steps of: a) 2 to 20% by weight of an anionic surfactant; b) 0.2 to 8% by weight of at least one acid having a pKa of 1 to 8 and a logP of 0 to 4.95; and c) water, and d) Optionally, a liquid structurant A liquid composition comprising: The present invention relates to a liquid composition in which the composition has a pH of 2.9 to 5.2 when expressed as a 50% aqueous solution, and further, the composition is substantially free of sulfates.

[0011] In a second aspect, the present invention provides a method for producing a composition comprising the steps of: a) contacting the surface with a cleaning solution comprising a liquid composition from the first aspect of the invention and water; and b) rinsing said cleaning solution from said surface. 1. A method for reducing the presence of antimicrobial agents (both gram negative and gram positive) on a surface in need thereof, comprising: The liquid composition has antimicrobial activity in a 50% cleaning solution and has a Log 2 H of at least 1.0 after 15 seconds (preferably after 10 seconds) of contact with a surface (e.g., skin or countertop) requiring antimicrobial reduction, preferably at least 2.0 after 25 seconds (preferably after 20 seconds) of contact, and most preferably at least 2.75 (preferably 3.0) after 40 seconds (preferably after 35 seconds, most preferably after 30 seconds) of contact against E. coli ATCC 10536 and Staphylococcus aureus ATCC 6538. 10 The present invention relates to a method for providing a reduction

[0012] In a third aspect, the present invention provides a 50% aqueous solution that has a Log 2 H of at least 1.0 after 15 seconds of contact with a surface requiring antimicrobial reduction (e.g., skin or countertop), preferably at least 2.0 after 25 seconds of contact, and most preferably at least 3.0 after 35 seconds of contact against E. coli ATCC 10536 and S. aureus ATCC 6538. 10The present invention relates to the use of the liquid composition of the first aspect of the present invention to provide a reduction in

[0013] Skin as used herein is meant to include the skin of the arms (including armpits), face, feet, neck, chest, hands, legs, buttocks, and scalp (including hair). A liquid composition (i.e., end-use composition) is defined to mean a composition that is ready for use in cleansing applications, and thus it can be a shampoo, makeup remover, face wash, or personal wash for the body and / or hands. Such liquid compositions are also suitable for use as home care cleansers (for inanimate objects), such as cleansers for cars, tables, windows, sinks, toilets, or laundry cleansers (for inanimate objects). In one embodiment of the present invention, the liquid composition is a personal wash composition for the skin. In another embodiment, the liquid composition is a personal wash composition for the hands. The liquid composition is typically used at 30-70% by weight of the composition and 70-30% by weight of water to produce an aqueous solution or cleaning solution having a pH of 2.9-5.2. For the avoidance of doubt, a 50% aqueous solution (or cleaning solution) means 50% water and 50% liquid composition or end use composition by weight, thus 1:1 water:liquid composition dilution, and the liquid composition itself is considered to be formulated with water, without the water used for dilution. The pH of the liquid composition is considered to be essentially the same as the cleaning solution. The liquid compositions of the present invention are suitable for delivering pharmaceutical active ingredients (such as corticoids, antihistamines and / or antibiotics) in the cleaning solution. In a preferred embodiment, the liquid compositions and the resulting cleaning solutions are cosmetic and non-therapeutic compositions suitable for removing soils (water-soluble and oil-soluble) from the skin, particularly the skin of the hands. The liquid compositions and cleaning solutions are surprisingly mild while providing antibacterial benefits. Such slurries are surprisingly mild while providing antibacterial benefits. Mild as used herein means having a zein value of ≦7, as defined and measured by the method described in the Examples.Antimicrobial efficacy is a Log reduction against E. coli ATCC10536 and S. aureus ATCC6538 of at least 1.0 after 15 seconds of contact with a surface such as skin requiring antimicrobial reduction, preferably at least 2.0 after 25 seconds of contact, and most preferably at least 3 after 35 seconds of contact, for a 50% cleaning solution. 10 A liquid structurant means an ingredient that contributes to the stability of a liquid composition as a lamellar composition. As used herein, pKa is defined as the -log 10 Ka, where Ka is the acid dissociation constant. LogP is log 10 (Partition coefficient), and the partition coefficient P is [compound] オクタノール / [compound] 水 is equal to.

[0014] By substantially free is meant 3.5% by weight or less of the total weight of the liquid composition, preferably less than 1.5% by weight of the total weight of the liquid composition. In yet another embodiment, substantially free means less than 1% by weight, preferably less than 0.5% by weight of the total weight of the liquid composition. As used herein, "substantially free" means comprising 0.00001% to 3.5% by weight, or 0.00001% to 1% by weight, or 0.00001% to 0.5% by weight, or 0.0% by weight of the total weight of the liquid composition. With respect to soap, substantially free (of soap) means less than 5.5% by weight, preferably less than 4.5% by weight, and most preferably less than 3.75% by weight of soap, based on the total weight of the liquid composition. In one embodiment of the present invention, the liquid composition comprises 0.00001 to 3.5% by weight or 0.001 to 3.35% by weight of soap. In another embodiment, the liquid composition is free of soap (0.0% by weight).

[0015] As used herein, betaine (or sultaine) refers to the surfactant derived therefrom. In the case of betaine, for example, the surfactant derived therefrom is cocoamidopropyl betaine.

[0016] In yet another embodiment of the invention, the liquid composition can be formulated to be substantially free of ethanol, parabens, formaldehyde donors, sulfates, glycinates, glutamates, halogenated antimicrobial actives, and any ingredients that have been tested on animals. In yet another embodiment of the invention, the aqueous solution or cleaning solution (1:1, water:liquid composition, respectively) contains less than 1% or 0.0% by weight of C. 16-18 methyl ester sulfonates, glycinates, carboxylates, glutamates, and / or alpha olefin sulfonates. In yet another embodiment, the cleaning composition contains less than 2% by weight silicone or 0.0% by weight silicone (e.g., no cyclosiloxanes such as decamethylcyclopentasiloxane).

[0017] Skin benefit agents may be used in the liquid compositions of the present invention, and such agents may be water-soluble or oil-soluble. The liquid compositions have a viscosity of 2000-15000 mPa, and a 50% aqueous solution has a viscosity of 20-1,500 mPa.s, as measured by a Brookfield heipath helipath TD at 4 rpm for 1 minute at 25°C, unless otherwise stated. All ranges described herein are intended to include all ranges contained therein, unless expressly stated otherwise. The term comprising is intended to include the terms consisting essentially of and consisting of. For the avoidance of doubt and for the sake of illustration, an aqueous solution comprising water, an anionic surfactant, and an acid is intended to include solutions consisting essentially of and consisting of. Except in comparative operating examples, or unless otherwise expressly stated, all numbers in this description indicating amounts or proportions of ingredients or conditions and / or physical properties and / or uses of ingredients should be understood to be modified by the word "about". DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0018] With respect to anionic surfactants suitable for use in the liquid compositions of the present invention, such surfactants include glutamates, aspartates, aliphatic sulfonates, such as primary alkanes (e.g., C8-C 22 ) sulfonates, primary alkanes (e.g., C8-C 22 ) Disulfonate, C8-C 22 Alkenesulfonates, C8-C 22 They may be hydroxyalkanesulfonates or alkyl glyceryl ether sulfonates (AGS), as well as aromatic sulfonates such as alkylbenzene sulfonates.

[0019] The anionic surfactants used in the present invention may optionally contain some alkyl sulfates (e.g., C 12 -C 18 The sulfates may include alkyl sulfates (including alkyl ether sulfates) and / or alkyl ether sulfates (including alkyl glyceryl ether sulfates). As noted herein, the liquid compositions of the present invention are substantially free of sulfates (e.g., free of sulfate surfactants). If used, suitable sulfates include those having the formula: [ka]

[0020] where R is an alkyl or alkenyl having 8 to 18 carbons, preferably 12 to 18 carbons, n has an average value of at least 1.0, preferably less than 5, and most preferably 1 to 4, and M is a solubilizing cation such as sodium, potassium, ammonium, or substituted ammonium. As stated above, sulfate salts, if optionally used, constitute no more than 3.5% by weight of the liquid composition.

[0021] In one embodiment of the invention, the anionic compounds include alkyl sulfosuccinates (monoalkyl and dialkyl, e.g., C6-C 22 including sulfosuccinates); alkyl and acyl taurates (often methyl taurate), alkyl and acyl sarcosinates, sulfoacetates, phosphates and phosphonates C8-C22 Alkyl, alkyl phosphate esters and alkoxyalkyl phosphate esters, acyl lactates, succinic and maleic acids C8-C 22 Monoalkyls, sulfoacetates, alkylglucosides and acylisethionates are also possible.

[0022] The sulfosuccinate is a monoalkyl sulfosuccinate having the formula: [ka]

[0023] and amide-MEA sulfosuccinate of the formula: [ka]

[0024] In the formula, R 1 is C8-C 22 It is an alkyl group.

[0025] The sarcosinates suitable for use are generally represented by the formula: [ka]

[0026] In the formula, R 2 is C8-C 20 It is an alkyl group.

[0027] Taurates suitable for use are generally characterized by the formula: [ka]

[0028] In the formula, R 3 is C8-C 20 is an alkyl group, R 4 is a C1-C4 alkyl group and M is a solubilizing cation as previously described.

[0029] Suitable isethionates for use in the liquid compositions include C8-C 18 Acyl isethionate (C 1-4 The esters may be substituted with head groups such as alkyl, preferably methyl, etc. These esters are typically prepared by reaction of an alkali metal isethionate with mixed aliphatic fatty acids having 6-18 carbon atoms and an iodine value of less than 20. Often at least 75% of the mixed fatty acids have 12-18 carbon atoms and up to 25% have 6-10 carbon atoms. Isethionates with head-substituted isomers are described in WO 94 / 09763 and U.S. Pat. Nos. 2,810,747 and 2,820,818, the disclosures of which are incorporated herein by reference.

[0030] The acyl isethionates that can be used can be alkoxylated isethionates such as those described in U.S. Patent No. 5,393,466, entitled "Polyalkoxylated Fatty Acid Esters of Isethionic Acid," issued to Ilardi et al. on Feb. 28, 1995, and incorporated herein by reference. The compounds have the general formula: [ka]

[0031] In the formula, R 5 is an alkyl group having 8 to 18 carbon atoms, m is an integer of 1 to 4, X and Y are each independently hydrogen or an alkyl group having 1 to 4 carbon atoms, and M is the above-mentioned solubilizing cation.

[0032] Examples of glutamate salts suitable for use in the present invention include sodium lauroyl glutamate, sodium cocoyl glutamate, potassium lauroyl glutamate, potassium cocoyl glutamate, disodium cocoyl glutamate, mixtures thereof, etc. Illustrative examples of aspartic acids suitable for use alone or together with glutamate salts and / or other anionic surfactants include sodium lauroyl aspartate, potassium lauroyl aspartate, sodium cocoyl aspartate, potassium cocoyl aspartate, mixtures thereof, etc.

[0033] Citrates such as laureth-7 citrate are suitable for use as anionic surfactants, as are carboxylates such as sodium laureth-5 carboxylate, sodium lauryl glucose carboxylate, sodium alkylpaleth-8 carboxylate, sodium alkylpaleth-12 carboxylate, etc. Sulfonated tallow fatty acids are yet another class of anionic materials suitable for use.

[0034] Succinates suitable for use in the liquid compositions of the present invention include disodium laureth sulfosuccinate, disodium lauryl sulfosuccinate, MEA-sulfosuccinate, or mixtures thereof. Sarcosinates such as sodium and / or potassium lauroyl sarcosinate are also suitable for use.

[0035] In one embodiment of the invention, the anionic surfactant used is sodium cocoyl isethionate, sodium lauroyl isethionate, sodium myristoyl isethionate, sodium oleoyl isethionate, ammonium oleoyl isethionate or mixtures thereof. Other isethionate salts suitable for use include acyl alkyl isethionates such as acyl 1-alkyl, 2-alkyl and 1,2-alkyl isethionates, the alkyl groups of which are often C1-C4-alkyl, preferably C1 and / or C2 alkyl, most preferably methyl. In one embodiment of the invention, mixtures of acyl 1-alkyl and acyl 2-alkyl isethionates in weight ratios of 1:25 to 1:2, preferably 1:20 to 1:3, most preferably 1:18 to 1:4, respectively, can be used, the alkyl groups of which are C1-C6 alkyl, preferably methyl and / or ethyl. In yet another embodiment of the invention, the acyl alkyl isethionate is sodium lauroyl methyl isethionate in a mixture in which at least 50-95% by weight, preferably 60-85% by weight, and most preferably 65-80% by weight, of the methyl group is on carbon 2 of the isethionate group, based on the total weight of the isethionate in the liquid composition.

[0036] In yet another embodiment, the anionic surfactant is a taurate such as sodium lauroyl taurate, sodium methyl lauroyl taurate, sodium methyl cocoyl taurate, sodium methyl oleoyl taurate, sodium methyl myristoyl taurate, potassium methyl myristoyl taurate, calcium methyl lauroyl taurate, potassium methyl lauroyl taurate, ammonium methyl lauroyl taurate, or mixtures thereof.

[0037] In yet another embodiment of the present invention, the anionic surfactant used in the liquid composition of the present invention is a mixture of any of those described herein.

[0038] However, in another embodiment, the anionic surfactant used is an isethionate, a taurate, or a mixture thereof. In the case of a mixture of an isethionate and a taurate, the mixture typically has a weight ratio of taurate to isethionate of 99:1 to 1:99, preferably 15:85 to 85:15, and most preferably 25:75 to 75:25, based on the total weight of the taurate and the isethionate in the liquid composition. In yet another embodiment, the weight ratio of taurate to isethionate in the liquid composition is 35:65 to 65:35, or 58:42 to 42:58, based on the total weight of the taurate and the isethionate in the liquid composition.

[0039] In many cases, and in another embodiment, the anionic surfactant in the liquid composition of the present invention is at least 60% by weight isethionate and / or taurate, preferably at least 65% by weight isethionate and / or taurate, and most preferably at least 70-100% by weight isethionate and / or taurate, based on the total weight of the anionic surfactant in the bar composition. Liquid compositions in which the anionic surfactant is 100% by weight isethionate or 100% by weight taurate (based on the total weight of the anionic surfactant in the liquid composition) are also within the scope of the present invention. It is also within the scope of the present invention for the liquid composition to comprise only anionic surfactant (i.e., 100%) as the surfactant in the composition, and thus a liquid composition comprising an anionic surfactant and 0.0% by weight betaine is within the scope of the present invention. In yet another embodiment of the invention, the anionic surfactant and the zwitterionic surfactant are used in a weight ratio of anionic surfactant to zwitterionic surfactant of 5:1 to 1.35:1, or 4:1 to 3.5:1, or 3.5:1 to 2.75:1, or 3:1 to 2.65:1. In yet another embodiment of the invention, the anionic surfactant is a taurate, an isethionate, or both, and the zwitterionic surfactant is a betaine. In an often desirable embodiment, the anionic surfactant is a taurate and the zwitterionic surfactant is a betaine, used in the liquid composition in the specified weight ratios.

[0040] The anionic surfactant typically comprises 2 to 20% by weight, preferably 3 to 15% by weight, and most preferably 4 to 9% by weight of the liquid composition. In one embodiment of the present invention, the anionic surfactant comprises 3 to 12% by weight, 3 to 10% by weight, or 4 to 9% by weight of the liquid composition.

[0041] Optionally, amphoteric surfactants (which can be zwitterionic depending on pH) suitable for use in the present invention include sodium acylamphoacetate, sodium acylamphopropionate, disodium acylamphodiacetate, and disodium acylamphodipropionate, in which the acyl (i.e., alkanoyl group) is C7-C 18 The amphoteric surfactant may include an alkyl moiety. Illustrative examples of amphoteric surfactants suitable for use include sodium lauroamphoacetate, sodium cocoamphoacetate, or mixtures thereof. When present, such surfactants comprise 0.00001 to 5.0% by weight of the liquid composition, preferably 0.1 to 4.5% by weight, and most preferably 0.1 to 3.5% by weight. The liquid composition may comprise 0.00001 to 2% by weight of the liquid composition of an amphoteric surfactant, or may be completely free (0.0% by weight).

[0042] Regarding the zwitterionic surfactants that may optionally be used in the present invention, such surfactants contain at least one acid group. Such acid group may be a carboxyl or sulfonic acid group. They often contain a quaternary nitrogen and therefore may be quaternary amino acids. They often contain an alkyl or alkenyl group of 7 to 18 carbon atoms and typically conform to the overall structural formula: [ka]

[0043] In the formula, R 6 is an alkyl or alkenyl having 7 to 18 carbon atoms; R 7 and R 8each independently represents an alkyl, hydroxyalkyl, or carboxyalkyl group having 1 to 3 carbon atoms; q is 2 to 4 and r is 0 to 1; A is an alkylene group having 1 to 3 carbon atoms which may be substituted with hydroxyl, and B is -CO2- or -SO3-.

[0044] Suitable zwitterionic surfactants for optional use in the present invention include betaines of the formula: [ka]

[0045] and amidobetaines of the following formula: [ka]

[0046] In the formula, t is 2 or 3.

[0047] In both equations, R 6 , R 7 and R 8 is as defined above. R 6 In particular, coconut oil-derived C 12 and C 14 A mixture of alkyl groups means that R 6 At least half, preferably at least three quarters, of the groups have 10 to 14 carbon atoms. 7 and R 8 is preferably methyl.

[0048] Another option is where the zwitterionic surfactant is a sulfobetaine of the formula: [ka]

[0049] or [ka]

[0050] [wherein u is 2 or 3.] or -(CH2)3SO3 - -CH2C(OH)(H)CH2SO3 - These are variants of the .

[0051] In these formulas, R 6 , R 7 and R 8 is as defined above.

[0052] Specific examples of zwitterionic surfactants suitable for use include coco betaine, cocoamidopropyl betaine, lauryl betaine, lauryl hydroxysulfobetaine, lauryl dimethyl betaine, cocoamidopropyl hydroxysulfobetaine, behenyl betaine, capryl / capramidopropyl betaine, coco dimethyl carboxymethyl betaine, stearyl betaine, lauryl amidopropyl betaine, mixtures thereof, etc. Additional zwitterionic surfactants suitable for use include lauryl hydroxysultaine and / or cocamidopropyl sultaine. In a preferred embodiment, the zwitterionic surfactant used in the liquid composition of the present invention is cocamidopropyl betaine.

[0053] When zwitterionic surfactants are used, they may comprise 0.0001-15% by weight, preferably 1.0-12% by weight, and most preferably 1.5-10% by weight of the liquid composition. The liquid composition may comprise 0.0001-6.5% by weight of the liquid composition of zwitterionic surfactant, 1.5-5.5% by weight, or 1.6-4% by weight of the liquid composition of zwitterionic surfactant, or may be completely free of zwitterionic surfactant (0.0% by weight). In another embodiment of the present invention, the zwitterionic surfactants such as betaines and / or sultaines as used in the present invention comprise 0.05-50% by weight, preferably 0.08-30% by weight, and most preferably 0.5-20% by weight of the total weight of the zwitterionic surfactant and anionic surfactant used in the liquid composition. In yet another embodiment, the betaines and / or sultaines comprise 1-12% by weight of the liquid composition and the anionic surfactant comprises 2-15% by weight. In another embodiment, the betaine and / or sultaine comprises 1.5-7% by weight and the anionic surfactant comprises 2.5-8% by weight of the liquid composition.

[0054] In yet another embodiment, when betaine and / or sultaine are used in the liquid composition of the present invention, the anionic surfactant comprises less than 5% by weight, preferably 20% by weight, most preferably 15% by weight of isethionate based on the total weight of the anionic surfactant in the liquid composition. In yet another embodiment, when betaine and / or sultaine are used in the liquid composition of the present invention, the anionic surfactant comprises more than 15% by weight, preferably more than 20% by weight, most preferably more than 25% by weight of taurate based on the total weight of the anionic surfactant in the liquid composition. In yet another embodiment, when betaine and / or sultaine are used, the anionic surfactant is 0.001-7.5% by weight of taurate or 3.5-5.5% by weight of taurate based on the total weight of the liquid composition.

[0055] In yet another embodiment of the invention, the anionic surfactant and the zwitterionic surfactant are used in a weight ratio of the anionic surfactant to the zwitterionic surfactant of 5:1 to 1.35:1, or 4:1 to 3.5:1, or 3.5:1 to 2.75:1, or 3:1 to 2.65:1. In yet another embodiment of the invention, the anionic surfactant is a taurate, an isethionate, or both, and the zwitterionic surfactant is a betaine. In an often desirable embodiment, the anionic surfactant is a taurate and the zwitterionic surfactant is a betaine, which are used in the liquid composition in the specified weight ratio.

[0056] In a further embodiment, when the anionic surfactant used is 95-100% by weight of taurate (based on the total weight of the anionic surfactant), 7-40% by weight, preferably 8-35% by weight, most preferably 9-32% by weight of a zwitterionic surfactant (such as a betaine) is used, based on the total weight of the anionic and zwitterionic surfactants used in the liquid composition, in which case 1.8-3.2% by weight, or 2-3% by weight, or 2.25-2.75% by weight of an acid having a pKa of 1-8 and a logP of 0-4.95, based on the total weight of the liquid composition, is used, especially when the pH of such composition is 3.5-4.5.

[0057] Nonionic surfactants may be used in the liquid compositions of the present invention. When nonionic surfactants are used, they are typically present at low levels of 0.05, 0.15, 1, 1.5 or 2% by weight to high levels of 6, 8, 10 or 12% by weight of the liquid composition. Nonionic materials that can be used include, in particular, compounds having a hydrophobic group and a reactive hydrogen atom, such as the reaction products of aliphatic alcohols, acids, amides or alkylphenols with alkylene oxides, especially ethylene oxide alone or with propylene oxide. Specific nonionic surfactant compounds include alkyl (C6-C 22 ) Phenol ethylene oxide condensate, aliphatic (C8-C 18) The condensation products of primary or secondary straight or branched chain alcohols with ethylene oxide, and the products produced by the condensation of ethylene oxide with the reaction products of propylene oxide and ethylenediamine.Other nonionic surfactants include long chain tertiary amine oxides, long chain tertiary phosphine oxides, dialkyl sulfoxides, etc.

[0058] Nonionic surfactants that may be used include fatty acid / alcohol ethoxylates having the following structure: a) HOCH2(CH2) s (CH2CH2O) v H or b) HOOC(CH2) c (CH2CH2O) d H, in which s and v are each independently an integer up to 18, and c and d are each independently an integer greater than or equal to 1. In one embodiment of the invention, s and v are each independently an integer between 6 and 18, and c and d are each independently an integer between 1 and 30. Other options for nonionic surfactants include those of the formula HOOC(CH2) l -CH=CH-(CH2) k (CH2CH2O) z H, in which i and k are each independently 5 to 15, and z is 5 to 50. In another embodiment of the present invention, i and k are each independently 6 to 12, and z is 15 to 35.

[0059] The nonionic surfactant may also be a sugar amide, such as a polysaccharide amide. Specifically, the surfactant may be one of the lactobionamides described in U.S. Patent No. 5,389,279 to Au et al., entitled "Compositions Containing Nonionic Glycolipid Surfactants," issued on February 14, 1995, which is incorporated herein by reference. Or, it may be one of the sugar amides described in U.S. Patent No. 5,009,814 to Kelkenberg, entitled "Use of N-Polyhydroxyalkyl Fatty Acid Amides as Thickeners for Liquid Aqueous Surfactant Systems," issued on April 23, 1991, which is incorporated herein by reference.

[0060] In one embodiment of the present invention, cationic surfactants may be used in the liquid compositions of the present invention. One class of optional cationic surfactants includes heterocyclic ammonium salts such as cetyl or stearyl pyridinium chloride, alkylamidoethyl pyridinium methylsulfate, and lapyrium chloride.

[0061] Tetraalkylammonium salts are another useful class of cationic surfactants suitable for any application. Examples include cetyl or stearyl trimethylammonium chloride or bromide, coconut or tallow trimethylammonium halide, behenyl trimethylammonium halide or methyl sulfate, decyl isononyl dimethyl ammonium halide, ditallow (or distearyl) dimethyl ammonium halide, and behenyl dimethyl ammonium chloride.

[0062] Still other types of cationic surfactants that can be used include various ethoxylated quaternary amines and ester quats, such as PEG-5 stearyl ammonium lactate (e.g., Genamin KSL from Clariant), PEG-2 coco ammonium chloride, PEG-15 hydrogenated tallow ammonium chloride, PEG 15 stearyl ammonium chloride, dipalmitoyl ethyl methyl ammonium chloride, dipalmitoyl hydroxyethyl methyl sulfate, and stearyl amidopropyl dimethylamine lactate.

[0063] Further optional cationic surfactants suitable for any use also include quaternized hydrolysates of silk, wheat and keratin proteins, and it is within the scope of the present invention to use mixtures of the aforementioned cationic surfactants.

[0064] If a cationic surfactant is used, it will comprise no more than 1.75% by weight of the liquid composition. If present, it will typically comprise from 0.001 to 0.75% by weight of the liquid composition, more typically from 0.01 to 0.5% by weight or 0.0% by weight.

[0065] In one embodiment of the invention, the liquid composition of the invention can optionally contain 0.0001-0.5 wt.% of a polymeric quaternary ammonium compound (including salts thereof). In another embodiment, the liquid composition contains less than 0.3 wt.% of a polymeric quaternary ammonium compound. In yet another embodiment, the liquid composition contains less than 0.01 wt.% of a polymeric quaternary ammonium compound. In yet another embodiment, the liquid composition is free of polymeric quaternary ammonium compounds (i.e., 0.0 wt.%).

[0066] Surfactants suitable for use in the present invention are available from suppliers such as Stepan Company, Clariant AG, Croda, Galaxy Surfactants, Sino Lion, Innospec, and Dow Chemical.

[0067] The acid suitable for use in the present invention is limited only insofar as it is suitable for use in consumer products and has a pKa of 1 to 8 and a logP of 0 to 4.95. Such acids are meant to include acids that are mono- and dicarboxylic acids, unsaturated acids, aromatic acids, phosphonic acids, or mixtures thereof.

[0068] In one embodiment of the invention, the acid (or mixture of acids used) has a pKa of 1.5 to 7, preferably 2 to 6.5, most preferably 2 to 5.5. In another embodiment of the invention, the pKa of the acid used is 2.5 to 4.8. In yet another embodiment, the pKa is 2.75 to 3.25. In one embodiment of the invention, the logP of the acid used is 0.65 to 4, preferably 1 to 3.3, most preferably 1.2 to 3. In yet another embodiment, the logP of the acid is 1.4 to 2.8 or 1.6 to 2.6.

[0069] With regard to the carboxylic acids suitable for use, illustrative examples include propionic acid, n-butyric acid, isobutyric acid, pentanoic acid, hexanoic acid, heptanoic acid, octanoic acid, nonanoic acid and / or decanoic acid. Dicarboxylic acids suitable for use include adipic acid and / or pimelic acid. Carboxylic acids may also include unsaturated ones such as but-3-enoic acid, but-2-ynoic acid, crotonic acid, isocrotonic acid, sorbic acid, angelic acid, tiglic acid and / or tetrol acid. It is also within the scope of the present invention to use the class of aromatic acids or in combination with other acids. Aromatic acids suitable for use include coumaric acid, benzoic acid, p-aminobenzoic acid, salicylic acid, capryloyl salicylic acid, 3-hydroxybenzoic acid, 4-hydroxybenzoic acid and / or gallic acid. Phosphonic acids suitable for use include 4-ethoxyphenylphosphonic acid, 4-methylphenylphosphonic acid, 4-chlorophenylphosphonic acid, phenylphosphonic acid, or mixtures thereof.

[0070] It is within the scope of the present invention to include any combination of acids having a pKa of 1-8 and a logP of 0-4.75, as described herein. In one embodiment of the present invention, the acid used is benzoic acid, p-aminobenzoic acid, capryloyl salicylic acid, and / or salicylic acid. In another embodiment, the acid used comprises salicylic acid and benzoic acid in a weight ratio of 5:95-95:5, preferably 25:75-75:25, and most preferably 40:60-60:40. In another embodiment of the present invention, the acid used consists essentially of salicylic acid and benzoic acid in a weight ratio of 5:95-95:5, preferably 25:75-75:25, and most preferably 40:60-60:40. In yet another embodiment of the present invention, the acids used are salicylic acid and benzoic acid in a weight ratio of 5:95 to 95:5, preferably 25:75 to 75:25, most preferably 40:60 to 60:40.

[0071] In yet another embodiment of the invention, the acids used are all benzoic acids (100% by weight of acids having pKa 1-8 and logP 0-4.75) or all salicylic acids.

[0072] The acid used constitutes 0.2-8% by weight of the liquid composition, preferably 0.5-7% by weight, most preferably 1-6%, 1-4.5%, 1.5-3.5% or 2-3% by weight.

[0073] The liquid composition of the present invention may be isotropic or lamellar, and if lamellar, it may contain from 0.1 to 12% by weight, preferably from 0.15 to 10% by weight, and most preferably from 0.2 to 8% by weight of a liquid (i.e., lamellar) structuring agent, based on the total weight of the liquid composition of the present invention.

[0074] Such structuring agents are typically fatty acids (or ester derivatives thereof) or fatty alcohols. Such materials include C8-C9 fatty acids such as caprylic acid, lauric acid, myristic acid, oleic acid, isostearic acid, linoleic acid, linolenic acid, ricinoleic acid, elaidic acid, arachidonic acid, myristoleic acid, palmitoleic acid, and mixtures thereof. 22 Acids, etc. Ester derivatives include propylene glycol isostearate, propylene glycol oleate, glyceryl isostearate, glyceryl oleate, and polyglyceryl diisostearate, mixtures thereof, etc. With regard to fatty alcohols suitable for use, these include cetyl alcohol, stearyl alcohol, behenyl alcohol, mixtures thereof, etc.

[0075] The structuring agent is preferably a fatty acid. More preferably, the structuring agent is selected from the group consisting of caprylic acid, lauric acid, myristic acid or mixtures thereof. In a particularly preferred embodiment, the structuring agent is lauric acid.

[0076] Water-soluble / water-dispersible polymers are optional components that are often desirable to add to the liquid compositions of the present invention to aid in enhancing and stabilizing the stability and viscosity of the composition. The water-soluble / or water-dispersible polymers used may be cationic, anionic, amphoteric or nonionic and typically have a weight average molecular weight of more than 100,000 Daltons. Such polymers comprise 0.05-6% by weight, preferably 0.07-5% by weight, and most preferably 0.1-4% by weight of the total weight of the liquid composition.

[0077] Examples of such polymers useful in the present invention include carbohydrate gums such as cellulose gum, microcrystalline cellulose, cellulose gel, hydroxyethyl cellulose, hydroxypropyl cellulose, sodium carboxymethyl cellulose, hydroxymethyl or carboxymethyl cellulose, methyl cellulose, ethyl cellulose, guar gum, karaya gum, tragacanth gum, arabic gum, acacia gum, agar gum, xanthan gum, and mixtures thereof; modified and unmodified starch granules having a gelatinization temperature of 30-85° C., and pregelatinized cold water soluble starches; polyacrylates; Cabopols; alkali soluble emulsion polymers such as Aculyn 28, Acuyln 22, or Carbopol Aqua SF1; cationic polymers such as modified polysaccharides including cationic guar available under the trade names Jaguar C13S, Jaguar C14S, Jaguar C17, or Jaguar C16 from RhonePoulenc; UCARE Polymer from Amerchol Corporation. Cationic modified celluloses such as JR30 or JR40; N-Hance 3000, N-Hance 3196, N-Hance GPX 215, or N-Hance GPX 196 from Hercules; synthetic cationic polymers such as MerQuat 100, MerQuat 280, Merquat 281, and Merquat 550 from Nalco; cationic starches such as StaLok® 100, 200, 300, and 400 from Henkel, Inc.'s Galactasol 800 series; Quadrosoft Um-200; and Polyquaternium-24.

[0078] Also suitable for use are gel-forming polymers such as modified or unmodified starch granules, xanthan gum, Carbopol, alkali soluble emulsion polymers and cationic guar gums such as Jaguar C13S, cationic modified celluloses such as UCARE polymers JR30 or JR40, etc. Also suitable for use are citrus peel fibers available under the name FiberDesign™ Sensation from suppliers such as Cargill.

[0079] The liquid composition of the present invention may contain a fatty acid, which is often a C8 to C 18 , preferably C 12 ~C 18 , most preferably C 16 ~C 18 Particularly preferred are palmitic acid and / or stearic acid, most preferably stearic acid.

[0080] Suitable additional fatty acids for optional inclusion are unsaturated fatty acids such as linoleic acid (C18:2), oleic acid (C18:1) or mixtures thereof. In one embodiment of the invention, when a fatty acid is used, it comprises less than 3% by weight, preferably less than 2% by weight, and most preferably less than 1% by weight of the total weight of the liquid composition. In another embodiment, the fatty acid comprises 0.0001-0.5% by weight of the total weight of the liquid composition, and no more than 35% by weight, preferably no more than 25% by weight, and most preferably no more than 18% by weight of the total weight of the unsaturated fatty acids used in the bar composition is oleic acid.

[0081] With regard to soaps suitable for optional use in the liquid compositions of the present invention, they are C8-C 10 soaps such as sodium, potassium or ammonium laurate, palmitate or stearate soaps (laurate, palmitate and / or stearate soaps). 14 and / or C. 16 ~C 18 Mention may be made of soap salts.

[0082] If optionally used, soap will typically comprise from 0.0001 to 6.5% by weight of the liquid composition, preferably from 0.1 to 5% by weight, most preferably from 1.5 to 2.25% by weight. Liquid compositions containing 0.0% by weight of soap are also within the scope of the present invention.

[0083] Water typically accounts for 35 to 85% by weight, preferably 45 to 80% by weight, and most preferably 55 to 80% by weight of the liquid composition before dilution with water to obtain an aqueous solution or cleaning solution.

[0084] For the cleaning solution, its pH is 2.9-5.2, preferably 3.3-4.9, most preferably 3.9-4.8. In another embodiment, the pH of the cleaning solution is 4-4.7 or 4.3-4.6. The liquid composition (i.e., end-use composition) solution has a viscosity of 2,000-15,000 mPa·s, preferably 3,000-10,000 mPa·s, most preferably 4,000-9,000 mPa·s. The cleaning solution has a viscosity of 20-1500 mPa·s, preferably 30-1250 mPa·s, most preferably 40-1000 mPa·s.

[0085] Optional but preferred ingredients that can be used in the liquid compositions of the present invention include preservatives to prevent the growth of potentially harmful microorganisms when preparing the end-use cleaning composition. Suitable conventional preservatives that can be used include propionate salts and various quaternary ammonium compounds. Often preferred preservatives are potassium sorbate, iodopropynyl butylcarbamate, phenoxyethanol, wasabi-based preservatives, imidazolidinyl urea, sodium dehydroacetate, and benzyl alcohol. Often desirable additives suitable for use in the liquid compositions of the present invention are 1,2-alkanediols, such as 1,2-octanediol, 1,2-hexanediol, or mixtures thereof. The liquid compositions may be comprised of a preservative system that is formaldehyde-free, paraben-free, or both.

[0086] When conventional preservatives and / or vicinal diol components are used, they comprise no more than 2% by weight of the liquid composition, preferably no more than 1% by weight, and most preferably 0.2-0.85% by weight. In one embodiment of the invention, 0.2-0.8% by weight of preservatives and / or vicinal diol components are used, based on the total weight of the liquid composition. Preferably, preservatives are used in the liquid compositions of the invention.

[0087] Conventional fragrance ingredients may be added to the liquid composition, such as eugenol, coumarin, linalyl acetate, citronellal, iris concentrate, terpinyl acetate, terpineol, thymol, pinenes (e.g., α-pinene and β-pinene), and citronellol, etc. Such ingredients will comprise 0.01 to 1.2% by weight of the liquid composition at the time of use, preferably 0.1 to 1% by weight, and most preferably 0.1 to 0.65% by weight.

[0088] Other optional ingredients suitable for use, particularly when the liquid composition is used as an anti-dandruff shampoo, include zinc pyrithione, octopirox, or mixtures thereof. Each of these substances may range from 0.05 to 3% by weight, preferably from 0.1 to 2% by weight, of the total weight of the liquid composition.

[0089] Additional optional ingredients that may be used include sensory oils and / or exfoliants. Desirable oils include rose, lime, coconut, lavender, argan, sweet almond oil, or mixtures thereof. Exemplary exfoliants that may be used include salt, sugar, apricot, walnut shells, rice, nutmeg, and / or oatmeal powder. If used, sensory oils and exfoliants may comprise 0.1-2% by weight of the liquid composition, with the proviso that the combined amount of fragrance and sensory oil does not exceed 2.5% by weight of the composition, and preferably does not exceed 2.0% by weight of the composition.

[0090] The liquid composition may contain vitamins. Examples of vitamins include vitamin B2, vitamin B3 (niacinamide), vitamin B6, vitamin C, vitamin E, folic acid and biotin. Derivatives of vitamins may also be used. For example, vitamin C derivatives include ascorbyl tetraisopalmitate, magnesium ascorbyl phosphate and ascorbyl glycoside. Derivatives of vitamin E include tocopheryl acetate, tocopheryl palmitate and tocopheryl linoleate. DL-panthenol and derivatives may also be used. The total amount of any vitamins, if present, may range from 0.001 to 5%, preferably 0.01 to 3%, optimally 0.1 to 1% by weight of the composition.

[0091] Other optional additives suitable for use include resorcinols such as 4-ethylresorcinol, 4-hexylresorcinol, 4-phenylethylresorcinol, dimethoxytolylpropylresorcinol, 4-cyclopentylresorcinol, 4-cyclohexylresorcinol, thiamidol, etc.; alpha- and / or beta-hydroxy acids; retinoic acid and its derivatives (e.g., cis and trans); retinal; retinol; retinyl esters such as retinyl acetate, retinyl palmitate, and retinyl propionate; petroselinic acid; conjugated linoleic acid; 12-hydroxystearic acid; mixtures thereof, etc. Conditioning agents such as polyquaternium compounds (e.g., polyquaternium-67) may also be desirable for inclusion in the present invention. Such additives, if used, collectively constitute 0.001 to 3%, preferably 0.01 to 2%, and most preferably 0.1 to 1.5% by weight of the liquid composition.

[0092] Desquamation promoters may be present. Examples include alpha-hydroxycarboxylic acids, beta-hydroxycarboxylic acids. The term "acid" refers to the free acid as well as its salts, C1-C 30It is also meant to include alkyl or aryl esters, and lactones formed by removing water to form cyclic or linear lactone structures. Representative acids are glycolic acid and its derivatives, lactic acid, and malic acid. The amount of these materials, when present, can range from 0.01 to 3%, preferably 0.1 to 2%, by weight of the liquid composition.

[0093] The cosmetic cleansing composition of the present invention may optionally contain various herbal extracts. Representative extracts include those extracted from green tea, yarrow, ginseng, marigold, hibiscus, ginkgo, chamomile, licorice, aloe vera, grape seed, unshu mandarin, willow bark, sage, and rosemary. Humectants such as glycerol and other polyols (e.g., sorbitol) may also be included. Humectants and / or extracts such as sorbitol, when used, typically comprise 0.01 to 5% by weight, preferably 0.01 to 4% by weight, and most preferably 0.02 to 3% by weight of the liquid composition.

[0094] Another optional additive suitable for use includes cannabis oil containing 2.5 to 25% by weight of cannabigerol and / or 0.5 to 10% by weight of cannabidiol. If used, such oil will comprise 0.0001 to 5% by weight of the composition, preferably 0.01 to 3% by weight of the liquid composition.

[0095] Also suitable for use are optionally chelating agents (e.g., EDTA), opacifiers (TiO2, particle size 50-1200 nm, preferably 50-350 nm), kaolin, bentonite, zinc oxide, iron oxide, mica, C 8-22Materials such as fatty acid substituted sugars, lipoic acid, retinoxytrimethylsilane (available from Clariant Corp. under the trade name Silcare 1M-75), dehydroepiandrosterone (DHEA), or mixtures thereof. Ceramides (such as ceramide 1, ceramide 3, ceramide 3B, and ceramide 6) and pseudoceramides can also be optionally included, as can 10-hydroxystearic acid. When these additional and optional materials are used, the amount can range from 0.0001 to 3%, preferably 0.001 to 2%, and most preferably 0.001 to 1.5% by weight of the liquid composition.

[0096] Colorants or dyes may also be included in the liquid composition. These materials may range from 0.05 to 5% by weight of the liquid composition, preferably from 0.1 to 2%.

[0097] Conditioning agents such as hydroxypropyltrimonium chloride, 5-ureidohydantoin and / or glyoxyldiureide can be used. If used, these ingredients comprise 0.5 to 4% by weight of the liquid composition, preferably 0.75 to 3% by weight, and most preferably 1 to 2% by weight.

[0098] The bar compositions of the present invention may also optionally include a sunscreen active. Particularly preferred are materials such as ethylhexyl p-methoxycinnamate available as Parsol MCX®, Avobenzene available as Parsol 1789®, and Benzophenone-3, also known as Oxybenzone. Inorganic sunscreen actives such as particulate titanium dioxide, zinc oxide, polyethylene, and various other polymers may also be used. Amounts of sunscreen when present may generally range from 0.01 to 3%, preferably from 0.5 to 2%, optimally from 0.75 to 1.5% by weight of the liquid composition.

[0099] Conventional buffers / pH adjusters can be used, including commonly used additives such as sodium hydroxide, potassium hydroxide, hydrochloric acid, citric acid / citric acid buffer, triethanolamine, or mixtures thereof, and pH is measured using a Thermo Fisher Scientific pH meter.

[0100] Any antimicrobial component may be used, but is not required. Exemplary components include quaternary ammonium compounds such as cetylpyridinium chloride, cetyltrimethylammonium chloride, cetyltrimethylammonium bromide, benzalkonium chloride, benzethonium chloride, cetrimide, or mixtures thereof. Cetrimonium chloride and / or bromide, chloroxylenol, antimicrobial lipids, antimicrobial peptides, or mixtures thereof may also be used. Triclosan may also be used, but is generally undesirable. A mixture of thymol and terpineol is often desired in use, typically in a weight ratio of 1:3 to 3:1, or 1:2 or 2:1, or 1:0.7 to 0.7:1. If used, such optional antimicrobial components will comprise 0.001 to 6%, preferably 0.01 to 5%, and most preferably 0.01 to 2.5% by weight of the liquid composition.

[0101] In preparing liquid compositions, conventional techniques may be used, including moderate shear mixing at atmospheric pressure and a temperature of 25-50°C.

[0102] A wide variety of packaging can be used for the liquid composition of the present invention. Laminated boxes and bags as well as plastic containers can be used. Preferably, the packaging used for the composition of the present invention is packaging made from recycled materials such as post-consumer resin or biodegradable materials. Most preferably, the liquid composition is sold in biodegradable packaging materials such as post-consumer resin.

[0103] The following examples are provided to facilitate understanding of the invention and are not intended to limit the scope of the claims. EXAMPLES

[0104] Example I The formulations shown in Table I as Samples 1A-D were prepared in accordance with the present invention. Sample 1E formulation is provided as a comparative formulation. All weight percentages (wt %) are based on the total weight of active in the prepared liquid composition. [Table 1]

[0105] Example II Antibacterial efficacy evaluation method The antimicrobial efficacy of the formulation samples in Table I was evaluated by a procedure similar to that described in ASTM International Test Method ASTM E2315-16 entitled "Standard Guide for Evaluation of Antimicrobial Activity Using the Time-Kill Procedure," which is incorporated herein by reference. The data are provided in Table II.

[0106] E. coli ATCC10536 and S. aureus ATCC6538 were used in this study to represent Gram-negative and Gram-positive bacteria, respectively. The bacteria were stored at -80°C. Fresh isolates were grown in duplicate on tryptic soy agar plates at 37°C for 24 hours before each experiment. From these cultures, 1.5 x 10 8 ~5×10 8 Vegetative bacterial cultures in colony forming units / mL (CFU / mL) were prepared and used as challenge inoculum for the experiments. Dilutions of 50% test formulation were exposed to the inoculum at 25°C. After 10, 20, 30 or 60 seconds of exposure, the mixture was neutralized to stop the antibacterial activity of the test solution. The neutralized bacterial solutions were serially diluted, plated on solid media, incubated for 24 hours, and viable cells were enumerated by colony counting. Bactericidal activity is defined as the log reduction in CFU / mL relative to cultures not exposed to any test solution, i.e., untreated controls. The log reduction is calculated according to the following formula: Log 10 Decrease=Log 10 (Untreated control CFU)-Log 10(Test sample CFU) was used for the calculation. [Table 2]

[0107] The data in Table II show that liquid compositions 1B, 1C, and 1D made according to the present invention unexpectedly exhibited superior antimicrobial efficacy against both gram-positive and gram-negative bacteria, providing at least a 1 log reduction after 10 seconds of contact, a 2 log reduction after 20 seconds of contact, or a 3 log reduction after 30 seconds of contact. In contrast, comparative liquid composition 1E exhibited marginal efficacy, especially against gram-positive bacteria, when the level of organic acids was reduced.

[0108] Additionally, trained panelists repeatedly washed their hands with liquid compositions according to the present invention (1A-1D) as well as with a composition having a lower level of organic acid (1E). Unexpectedly, all panelists concluded that the liquid compositions made according to the present invention and having a higher level of organic acid were at least as gentle on the skin as the comparative formulations having less organic acid.

[0109] Example III Mildness rating Liquid compositions prepared according to the present invention were evaluated for skin mildness using the zein solubilization assay.

[0110] Zein powder (Sigma. 23625-1 kg, Lot No. SLBZ2926 or Acros Organic™ Zein), 0.3 g, was added to 10 mL of a 5% diluted aqueous solution of the test formulation and mixed for 30 minutes at room temperature. After 30 minutes, the resulting sample was visually inspected to determine if excess undissolved zein was present. If no excess zein was present, an additional 0.3 g of zein was added and mixed for an additional 30 minutes. The resulting sample was then filtered using a 0.45 micron filter. The filtrate was diluted with a 2% sodium dodecyl sulfate solution and the absorbance at 298 nm was measured to determine the amount of dissolved zein. A control experiment with a liquid composition without zein was prepared in a similar manner and measured at 298 nm to determine the background. The amount of dissolved zein is reported as follows:

[0111] Zein absorbance = [Absorbance of Zein in Liquid Composition (298 nm) - Absorbance of Background Sample (298 nm)] x Dilution Factor. Milder products will have less dissolved zein and lower absorbance values. Zein absorbance ranges that allow for a ranking of product mildness with respect to their ability to irritate the skin are defined and illustrated in Table III below. [Table 3]

[0112] Zein absorbance values ​​for all compositions shown in Table I (1A-1D) according to the present invention were measured to be between 3 and 7, which unexpectedly indicates that such compositions are mild to the skin yet have excellent antimicrobial efficacy.

[0113] Example IV Comparative samples of liquid compositions having different organic acid types The data showed that liquid compositions (4A, 4B, 4C, and 4D) having acids according to the invention and therefore within the claimed criteria, unexpectedly exhibited superior antimicrobial efficacy. In contrast, the liquid composition (4E) containing the specified non-claimed organic component (pKa=15.4, logP=1.1) had little or no efficacy. [Table 4]

[0114] Example V: The 10 second antimicrobial efficacy against S. aureus for formulations containing organic acid using the test procedure described above is shown in Table V, which demonstrates the unexpected additive synergistic effect of organic acid and surfactant. The data surprisingly shows that the use of both anionic surfactant and the preferred levels of organic acid enhances antimicrobial efficacy. In contrast, surfactants containing low levels of organic acid (5B) or organic acid alone without anionic surfactant (5C) provide no antimicrobial efficacy at all. All weight percentages (wt%) are based on the total weight of active material in the liquid composition produced. [Table 5]

[0115] Example VI Liquid compositions containing the same organic acid and varying ratios of anionic surfactant to zwitterionic surfactant were evaluated for antimicrobial efficacy against S. aureus at 10 seconds using the test procedure described above in this Example. The data in Table VI unexpectedly show that increasing the ratio of anionic surfactant to zwitterionic surfactant results in superior efficacy. [Table 6]

Claims

1. a) 2 to 20% by weight of an anionic surfactant; b) 0.2 to 8% by weight of at least one acid having a pKa of 1 to 8 and a logP of 0 to 4.95, the acid being benzoic acid, salicylic acid or a mixture thereof; c) water; and d) Optionally, a liquid structurant A liquid composition comprising: said composition in a 50% aqueous solution having a pH of 2.9 to 5.2; further comprising: 1.8-3.2% by weight, or 2-3% by weight, or 2.25-2.75% by weight, of an acid having a pKa of 1-8 and a logP of 0-4.95 is used based on the total weight of the liquid composition, when the anionic surfactant is 95-100% by weight of a taurate salt based on the total weight of the anionic surfactant, and the composition further comprises 7-40% by weight, preferably 8-35% by weight, and most preferably 9-32% by weight of a zwitterionic surfactant based on the total weight of the anionic surfactant and the zwitterionic surfactant used in the liquid composition, such that the composition has a pH of 3.5-4.

5.

2. 2. The liquid composition of claim 1, wherein the anionic surfactant is a taurate, an isethionate or a mixture thereof, and the composition containing 3.5% by weight or less of sulfate is isotropic or lamellar, and is a shampoo, a hand, body and / or face wash, or a home care cleanser.

3. 10. The liquid composition of any one of the preceding claims, wherein the acid is one or more of propionic acid, n-butyric acid, isobutyric acid, pentanoic acid, hexanoic acid, heptanoic acid, octanoic acid, nonanoic and / or decanoic acid, adipic acid, but-3-enoic acid, but-2-ynoic acid, crotonic acid, isocrotonic acid, sorbic acid, angelic acid, tiglic acid, tetrolic acid, coumaric acid, benzoic acid, p-aminobenzoic acid, salicylic acid, capryloylsalicylic acid, 3-hydroxybenzoic acid, 4-hydroxybenzoic acid, gallic acid, 4-ethoxyphenylphosphonic acid, 4-methylphenylphosphonic acid, 4-chlorophenylphosphonic acid, phenylphosphonic acid, or mixtures thereof.

4. 10. A liquid composition according to any one of the preceding claims, wherein the acid constitutes 0.5 to 7% by weight of the liquid composition, most preferably 1 to 6% or 1 to 4.5% by weight, or 1.5 to 3.5% by weight or 2 to 3% by weight.

5. 2. A liquid composition according to any one of the preceding claims, wherein the composition has a zein value of 7 or less.

6. The composition has antimicrobial activity in a 50% cleaning solution and has a Log β value against E. coli ATCC 10536 and S. aureus ATCC 6538 of at least 1.0 after 15 seconds of contact with a surface, preferably at least 10 seconds of contact, preferably at least 2.0 after 25 seconds of contact, preferably at least 20 seconds of contact, and most preferably at least 2.75, preferably 3.0 after 40 seconds of contact, preferably 35 seconds of contact, and most preferably at least 30 seconds of contact. １０ 20. The liquid composition of any one of the preceding claims, providing a reduction.

7. 8. The liquid composition of claim 7, wherein the surface is skin, hair or an inanimate object requiring antimicrobial reduction.

8. 2. A liquid composition according to any one of the preceding claims, wherein the composition further comprises a zwitterionic surfactant which is a betaine, a sultaine or a mixture thereof.

9. 10. The liquid composition of any one of the preceding claims, wherein the composition further comprises niacinamide, 12-hydroxystearic acid, retinol, resorcinol, thymol, terpineol, benzalkonium chloride, or a mixture thereof.

10. a) contacting the surface with a cleaning solution comprising a liquid composition according to any one of claims 1 to 9 and water; and b) rinsing the cleaning solution from the surface.

1. A method for reducing the presence of both gram-negative and gram-positive antimicrobial agents on a surface in need of antimicrobial reduction, comprising: The liquid composition has antimicrobial activity in a 50% wash solution and has a Log 200% antibacterial activity against E. coli ATCC 10536 and S. aureus ATCC 6538 of at least 1.0 after 15 seconds, preferably after 10 seconds, preferably after 25 seconds, preferably after 20 seconds, and most preferably after 40 seconds, preferably after 35 seconds, most preferably after 30 seconds, of at least 2.75, preferably 3.0, after 40 seconds, preferably after 35 seconds, most preferably after 30 seconds of contact. １０ and further wherein said liquid composition has a zein value of 7 or less.

11. Use of a composition according to any one of claims 1 to 10 to provide an antimicrobial effect on a surface, wherein the composition in a 50% cleaning solution has a Log 20 activity against E. coli ATCC 10536 and S. aureus ATCC 6538 of at least 2.75, preferably 3.0, after 15 seconds, preferably 10 seconds, of contact with a surface, being skin or hair or an inanimate object, and preferably at least 2.0, after 25 seconds, preferably 20 seconds, of contact, and most preferably at least 2.75, preferably 3.0, after 40 seconds, preferably 35 seconds, most preferably 30 seconds, of contact. １０ 4. The method of claim 1, wherein the liquid composition has a zein value of 7 or less.

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