FIELD OF THE INVENTION

The present invention is in the field of antimicrobial compositions. In particular, it relates to a composition comprising a modified amino acid antimicrobial active.

BACKGROUND OF THE INVENTION

Antibacterial household compositions are becoming more widely used with a focus on kitchen, bath and toilet cleaning. In addition to the sanitization or disinfection the compositions are required to clean and/or provide shine to the treated surface. Although there exists a number of hard surface antimicrobial treatment compositions, there is a desire to find more efficient and more environmentally friendly compositions. Furthermore, the development of isotropic formulations with gentle, biodegradable actives is desirable.

There is therefore the need for an antibacterial treatment composition that has a good environmental and human safety profile, that shows strong antibacterial efficacy, that can be used on food contact surfaces and that shows good cleaning, even on tough greasy soils, and/or leaves the surfaces shiny and without streaks.

SUMMARY OF THE INVENTION

According to the first aspect of the present invention, there is provided an antimicrobial composition.

According to the second aspect of the invention there is provided an article treated with the composition of the first aspect of the invention. The article is preferably in the form of any disposable or partially reusable substrate comprising one or more nonwoven layers. The article provides sanitization to surfaces, in particular hard surfaces. The article is sometimes herein referred to as “the article of the invention”.

According to the third aspect of the present invention, there is provided a method of sanitizing a surface using the composition of the invention. There is also provided the use of the composition of the invention to provide antimicrobial benefits to a surface, in particular to an inanimate surface.

The elements of the composition of the invention described in relation to the first aspect of the invention apply mutatis mutandis to the other aspects of the invention.

DETAILED DESCRIPTION OF THE INVENTION

The present invention encompasses an antimicrobial composition. The composition provides antimicrobial benefits. The composition comprises a modified amino acid and optionally a surfactant and/or organic solvent. The composition is preferably an aqueous composition comprising at least 50% by weight of the composition of water. The composition is especially suitable for treating hard surfaces.

As used herein, the phrase “chain atoms” means the sum of all atoms in an indicated group or moiety, excluding hydrogen atoms. The chain atoms may be in a linear configuration, a branched configuration, and/or a ring configuration.

All percentages, ratios and proportions used herein are by weight percent of the composition, unless otherwise specified. All average values are calculated “by weight” of the composition, unless otherwise expressly indicated. All ratios are calculated as a weight/weight level, unless otherwise specified.

All measurements are performed at 25° C. unless otherwise specified.

Unless otherwise noted, all component or composition levels are in reference to the active portion of that component or composition, and are exclusive of impurities, for example, residual solvents or by-products, which may be present in commercially available sources of such components or compositions.

Antimicrobial Composition

The composition of the invention is suitable to be used on surfaces, preferably on inanimate surfaces, more preferably on hard surfaces. The composition can be delivered onto the surface, by for example spraying the composition, followed by wiping the surface, preferably without rinsing or by using a substrate, such as a wipe impregnated with the composition of the invention. The composition provides good cleaning and/or shine to the treated surface. The composition can be a concentrated composition, that can be diluted before use or a ready-to-use composition. Preferably, the composition is a ready-to-use sprayable composition.

As used herein, the terms “microbe” or “microbial” should be interpreted to refer to any of the microscopic organisms studied by microbiologists or found in the use environment of a treated surface. Such organisms include, but are not limited to, bacteria and fungi as well as other single-celled organisms such as mould, mildew and algae. Viruses (enveloped and non-enveloped) and other infectious agents are also included in the term microbe.

“Antimicrobial” further should be understood to encompass both microbiocidal and microbiostatic properties. That is, the term includes microbe killing, leading to a reduction in number of microbes, as well as a retarding effect of microbial growth, wherein numbers may remain more or less constant (but nonetheless allowing for slight increase/decrease).

For ease of discussion, this description uses the term antimicrobial to denote a broad-spectrum activity (e.g., against bacteria and fungi, or against bacteria and viruses). When speaking of efficacy against a particular microorganism or taxonomic rank, the more focused term will be used (e.g., antifungal to denote efficacy against fungal growth in particular). Using the above example, it should be understood that efficacy against fungi does not in any way preclude the possibility that the same antimicrobial composition may demonstrate efficacy against another class of microbes.

By “hard surface”, it is meant herein hard surfaces found in households, especially domestic households. Surfaces to be cleaned include kitchens and bathrooms, e.g., floors, walls, tiles, windows, cupboards, sinks, showers, shower plastified curtains, wash basins, WCs, fixtures and fittings and the like made of different materials like ceramic, vinyl, no-wax vinyl, linoleum, melamine, glass, steel, kitchen work surfaces, any plastics, plastified wood, metal or any painted or varnished or sealed surface and the like. Household hard surfaces also include household appliances including, but not limited to refrigerators, freezers, washing machines, automatic dryers, ovens, microwave ovens, dishwashers and so on. Such hard surfaces may be found both in private households as well as in commercial, institutional and industrial environments.

The compositions herein are preferably aqueous compositions, comprising at least 50% by weight of the composition of water, preferably from 80% to 95% and more preferably from 90% to 96% by weight of the composition of water. Preferably, the compositions of the invention are clear compositions. Without wishing to be bound by theory, it is believed that in order to provide the best antimicrobial efficacy, the antimicrobial agent should be in solution. The composition should preferably be in the form of a clear, isotropic liquid.

The compositions of the present invention can be non-thickened, or water like, having a viscosity of from 1 mPa·s to 5 Pa·s, or can be thickened, having a viscosity of from 50 Pa·s to 1200 Pa·s, more preferably 100 Pa·s to 800 Pa·s, most preferably 200 Pa·s to 600 Pa·s when measured at with a AD1000 Advanced Rheometer from Atlas® shear rate 10 s⁻¹with a coned spindle of with a cone angle 2° and a truncation of ±60 μm.

The pH of the composition helps with antimicrobial efficacy. The pH of the composition is less than 9, preferably equal or less than 7, preferably from 2 to 5 as measured at 25° C. Accordingly, the compositions herein can comprise a pH adjusting agent.

Antimicrobial Composition

The composition of the invention comprises an antimicrobial agent. The antimicrobial agent needs only be present in germicidally effective amounts, which can be as little as 0.001% to less than 1% by weight of the composition. In more preferred compositions, the cleaning composition comprises the antimicrobial agent at a level of from about 0.0025 to about 10%, more preferably from 0.005% to 5%, more preferably from 0.01 to 1.5% by weight of the composition.

A germicidally effective amount of the antimicrobial agent typically results in at least a log 4 reduction of gram negative bacteria, using the method of EN13697 (Chemical Disinfectants Bactericidal Activity Testing), in 5 minutes.

Surfactant

The composition of the invention preferably comprises surfactants, more preferably from 0.01% to 10%, preferably from 0.05% to 8%, more preferably from 0.08% to 5%, more preferably 0.1% to 3% by weight of the composition of surfactant. The surfactant also contributes to the cleaning and/or shine provided by the composition. The composition of the invention can comprise an anionic surfactant. If the composition comprises an anionic surfactant, the mole ratio of antibacterial agent to anionic surfactant is greater than 1, preferably greater than 5, more preferably greater than 10.

Alkoxylated Alcohol Nonionic Surfactants

Suitable alkoxylated alcohol nonionic surfactants are according to the formula RO-(A)_nH, wherein: R is a primary C₄to C₁₈, preferably a C₆to C₁₆, more preferably a C₁₀to C₁₆and even more preferably from C₁₂to C₁₄branched or linear alkyl chain, or a C₆to C₂₈alkyl benzene chain; A is an ethoxy or propoxy or butoxy unit, or mixtures thereof, and wherein n is an integer from 1 to 30, preferably from 1 to 15, more preferably from 3 to 12 even more preferably from 3 to 8. Preferred R chains for use herein are the C₁₀to C₁₆linear or branched alkyl chains. Especially preferred for use herein is an alcohol alkoxylated having a C₁₂-C₁₄chain length and having from 8 to 10 ethoxy groups.

Suitable branched alkoxylated alcohols may be selected from the group consisting of: C₄-C₁₀alkyl branched alkoxylated alcohols, and mixtures thereof. The branched alkoxylated alcohol can be derived from the alkoxylation of C₄-C₁₀alkyl branched alcohols selected form the group consisting of: C₄-C₁₀primary mono-alcohols having one or more C₁-C₄branching groups.

By C₄-C₁₀primary mono-alcohol, it is meant that the main chain of the primary mono-alcohol has a total of from 4 to 10 carbon atoms. The C₄-C₁₀primary mono-alcohol can be selected from the group consisting of: methyl butanol, ethyl butanol, methyl pentanol, ethyl pentanol, methyl hexanol, ethyl hexanol, propyl hexanol, dimethyl hexanol, trimethyl hexanol, methyl heptanol, ethyl heptanol, propyl heptanol, dimethyl heptanol, trimethyl heptanol, methyl octanol, ethyl octanol, propyl octanol, butyl octanol, dimethyl octanol, trimethyl octanol, methyl nonanol, ethyl nonanol, propyl nonanol, butyl nonanol, dimethyl nonanol, trimethyl nonanol and mixtures thereof.

The C₄-C₁₀primary mono-alcohol can be selected from the group consisting of: ethyl hexanol, propyl hexanol, ethyl heptanol, propyl heptanol, ethyl octanol, propyl octanol, butyl octanol, ethyl nonanol, propyl nonanol, butyl nonanol, and mixtures thereof. Preferably the C₄-C₁₀primary mono-alcohol is selected from the group consisting of: ethyl hexanol, propyl hexanol, ethyl heptanol, propyl heptanol, and mixtures thereof.

The C₄-C₁₀primary mono-alcohol is most preferably ethyl hexanol, and propyl heptanol. Especially preferred for use herein are ethoxylated ethyl hexanol comprising from 4 to 10 ethoxy groups.

In the branched alkoxylated alcohol, the one or more C₁-C₄branching group can be substituted into the C₄-C₁₀primary mono-alcohol at a C1 to C3 position, preferably at the C1 to C2 position, more preferably at the C2 position, as measured from the hydroxyl group of the starting alcohol.

The branched alkoxylated alcohol can comprise from 1 to 14, preferably from 2 to 7, more preferably from 4 to 6 ethoxylate units, and optionally from 1 to 9, preferably from 2 to 7, more preferably from 4 to 6 of propoxylate units.

The branched alkoxylated alcohol is preferably 2-ethyl hexan-1-ol ethoxylated to a degree of from 4 to 6, and propoxylated to a degree of from 4 to 6, more preferably, the alcohol is first propoxylated and then ethoxylated. Another preferred branched alkoxylated alcohols are 2-alkyl-1-alkanols such as alkoxylated C₁₀guerbet alcohols with 1 to 14, preferably from 2 to 7, more preferably from 3 to 6 ethoxylate or ethoxylate-propoxylate units.

Non-limiting examples of suitable branched alkoxylated alcohols are, for instance, Ecosurf® EH3, EH6, and EH9, commercially available from DOW, and Lutensol® XP alkoxylated Guerbet alcohols & Lutensol® XL ethoxylated Guerbet alcohols available from BASF.

Linear alcohol alkoxylated nonionic surfactants preferred herein are alkoxylated nonionic surfactants with a C₈, C₁₀, C₁₂, mixtures of C₈to C₁₀, mixtures of C₁₀to C₁₂, mixtures of C₉to C₁₁linear alkyl chain and 8 or less ethoxylate units, preferably 3 to 8 ethoxylate units.

Non-limiting examples of suitable linear alkoxylated nonionic surfactants for use herein are Dobanol® 91-2.5 (R is a mixture of C₉and C₁₁alkyl chains, n is 2.5), Dobanol® 91-5 (R is a mixture of C₉to C₁₁alkyl chains, n is 5); Dobanol® 91-10 (R is a mixture of C₉to C₁₁alkyl chains, n is 10); Greenbentine DE60 (R is a C10 linear alkyl chain, n is 6); Marlipal 10-8 (R is a C₁₀linear alkyl chain, n is 8); Neodol 91-8 (R is a mixture of C₉to C₁₁alkyl chains, n is 8); Empilan® KBE21 (R is a mixture of C₁₂and C₁₄alkyl chains, n is 21); Lutensol ON30 (R is C₁₀linear alkyl chain, n is 3); Lutensol ON50 (R is C₁₀linear alkyl chain, n is 5); Lutensol ON70 (R is C₁₀linear alkyl chain, n is 7); Novel 610-3.5 (R is mixture of C₆to C₁₀linear alkyl chains, n is 3.5); Novel 810FD-5 (R is mixture of C₈to C₁₀linear alkyl chains, n is 5); Novel 10-4 (R is C₁₀linear alkyl chain, n is 4); Novel 1412-3 (R is mixture of C₁₂to C₁₄linear alkyl chains, n is 3); Lialethl® 11-5 (R is a C₁₁linear alkyl chain, n is 5); Lialethl® 11-21 (R is a mixture of linear and branched C₁₁alkyl chain, n is 21), or mixtures thereof.

The alkoxylated nonionic surfactant may be a secondary alcohol ethoxylate such as for example the Tergitol™-15-S surfactants having the general formula shown below and commercially available from DOW

[Image Omitted]

Preferred secondary alcohol ethoxylate surfactants have 3-9 EO units.

Another suitable alkoxylated nonionic surfactant is an alkyl ethoxy alkoxy alcohol, preferably wherein the alkoxy part of the molecule is propoxy, or butoxy, or propoxy-butoxy. More preferred alkyl ethoxy alkoxy alcohols are of formula (II):

[Image Omitted]

wherein:

- R is a branched or unbranched alkyl group having 8 to 16 carbon atoms;
- R¹is a branched or unbranched alkyl group having 1 to 5 carbon atoms;
- n is an integer from 1 to 10; and m is an integer from 6 to 35.

R is preferably from 12 to 15, preferably 13 carbon atoms. R¹is preferably a branched alkyl group having from 1 to 2 carbon atoms. n is preferably an integer from 1 to 5. m is preferably an integer from 8 to 25. Preferably, the weight average molecular weight of the ethoxylated alkoxylated nonionic surfactant of formula (II) is from 500 to 2000 g/mol, more preferably from 600 to 1700 g/mol, most preferably 800 to 1500 g/mol.

The ethoxylated alkoxylated nonionic surfactant can be a polyoxyalkylene copolymer. The polyoxyalkylene copolymer can be a block-heteric ethoxylated alkoxylated nonionic surfactant, though block-block surfactants are preferred. Suitable polyoxyalkylene block copolymers include ethylene oxide/propylene oxide block polymers, of formula (III):

(EO)_x(PO)_y(EO)_x, or

(PO)_x(EO)_y(PO)_x

wherein EO represents an ethylene oxide unit, PO represents a propylene oxide unit, and x and y are numbers detailing the average number of moles ethylene oxide and propylene oxide in each mole of product. Such materials tend to have higher molecular weights than most non-ionic surfactants, and as such can range between 1000 and 30000 g/mol, although the molecular weight should be above 2200 and preferably below 13000 to be in accordance with the invention. A preferred range for the molecular weight of the polymeric non-ionic surfactant is from 2400 to 11500 Daltons. BASF (Mount Olive, N.J.) manufactures a suitable set of derivatives and markets them under the Pluronic trademarks. Examples of these are Pluronic (trademark) F77, L62 and F88 which have the molecular weight of 6600, 2450 and 11400 g/mol respectively.

Other suitable ethoxylated alkoxylated nonionic surfactants are described in Chapter 7 of Surfactant Science and Technology, Third Edition, Wiley Press, ISBN 978-0-471-68024-6.

Most preferably the alkoxylated nonionic surfactant is selected from the group consisting of: 2-propylheptyl EO8 (Lutensol XL89-BASF); 2-propylheptyl EO5 (Lutensol XL50-BASF); C₁₀alcohol EO5 (Lutensol ON 50-BASF); C₁₀-alcohol EO7 (Lutensol ON 70-BASF); C₈-C₁₀EO5 (Novel 810 FD5 Sasol); C₁₀EO4 (Novel 10-4 Sasol); Tergitol 15-S-3; Tergitol 15-S-5; Tergitol 15-S-7; and Ethyl hexanol PO5EO6 (Ecosurf EH6-Dow). These surfactants have surprisingly been found to potentiate the antibacterial efficacy of the modified amino acids.

Alkyl Polyglycosides

Alkyl polyglycosides are biodegradable nonionic surfactants which are well known in the art and can be used in the compositions of the present invention. Suitable alkyl polyglycosides can have the general formula C_nH_2n+1O(C₆H₁₀O₅)_xH wherein n is preferably from 8 to 16, more preferably 8 to 14, and x is at least 1. Examples of suitable alkyl polyglucoside surfactants are the TRITON™ alkyl polyglucosides from Dow; Agnique PG, Disponil APG, Glucopon alkyl polyglucosides from BASF and Plantaren 2000 from BASF. Preferred alkyl polyglucoside surfactants are those where n is 8 to 12, more preferably 8 to 10, such as for example Triton™ CG50 (Dow). These surfactants have surprisingly been found to enhance the antimicrobial efficacy of the modified amino acids.

Alkyl Amine Oxide

Suitable amine oxide surfactants include: R₁R₂R₃NO wherein each of R₁, R₂and R₃is independently a saturated or unsaturated, substituted or unsubstituted, linear or branched hydrocarbon chain having from 1 to 30 carbon atoms. Preferred amine oxide surfactants are amine oxides having the following formula: R₁R₂R₃NO wherein R1 is a hydrocarbon chain comprising from 1 to 30 carbon atoms, preferably from 6 to 20, more preferably from 8 to 16 and wherein R₂and R₃are independently saturated or unsaturated, substituted or unsubstituted, linear or branched hydrocarbon chains comprising from 1 to 4 carbon atoms, preferably from 1 to 3 carbon atoms, and more preferably are methyl groups. R1 may be a saturated or unsaturated, substituted or unsubstituted linear or branched hydrocarbon chain.

Highly preferred amine oxides are C₈dimethyl amine oxide, C₁₀dimethyl amine oxide, C₁₂dimethyl amine oxide, C₁₄dimethyl amine oxide, and mixtures thereof C₈dimethyl amine oxide is commercially available under the trade name Genaminox® OC from Clariant; C₁₀dimethyl amine oxide is commercially available under the trade name Genaminox® K-10 from Clariant; C₁₂dimethyl amine oxide is commercially available under the trade name Genaminox® LA from Clariant and of Empigen OB from Huntsman; C₁₄amine oxide is commercially available under the trade name of Empigen OH 25 from Huntsman. Other suitable amine oxide surfactants are cocoyldiethoxy amine oxide available under the trade name of Genaminox CHE from Clariant, and cocamidopropyl amine oxide commercially available under the trade name of Empigen OS/A from Huntsman. Particularly preferred amine oxide surfactants are Cm dimethyl amine oxide such as Genaminox K-10. These surfactants have surprisingly been found to greatly enhance the antibacterial efficacy of the modified amino acids.

Alkyl Glucamide Surfactants

The composition of the invention may comprise an alkyl glucamide surfactant. Glucamide surfactants are non ionic surfactants in which the hydrophilic moiety (an amino-sugar derivative) and the hydrophobic moiety (a fatty acid) are linked via amide bonds. This results in a chemical linkage, which is highly stable under alkaline conditions. Particularly preferred alkyl glucamide surfactants are N-alkyl-N-acylglucamides of the formula

[Image Omitted]

Wherein Ra is a linear or branched, saturated or unsaturated hydrocarbyl group having 6 to 22 carbon atoms, and Rb is a C₁-C₄alkyl group. Particularly preferably, Rb in formula (III) is a methyl group. Non-limiting examples of these glucamide surfactants are: N-octanoyl-N-methylglucamide, N-nonanoyl-N-methylglucamide, N-decanoyl-N-methylglucamide, N-dodecanoyl-N-methylglucamide, N-cocoyl-N-methylglucamide, available under the trade name of GlucoPure Foam from Clariant, N-lauroyl/myristoyl-N-methylglucamide, (available under the trade name of GlucoPure Deg from Clariant, and N-octanoyl/decanoyl-N-methylglucamide, available under the trade name of GlucoPure Wet by Clariant.

Alkyl glucamine surfactants are suitable for the composition of the invention.

These surfactants are described in EP16184415 and US20190055496.

Zwitterionic and Amphoteric Surfactants

The hard surface cleaning composition may comprise an amphoteric surfactant, a zwitterionic surfactant, and mixtures thereof. Suitable zwitterionic surfactants typically contain both cationic and anionic groups in substantially equivalent proportions so as to be electrically neutral at the pH of use, and are well known in the art. Some common examples of zwitterionic surfactants are described in U.S. Pat. Nos. 2,082,275, 2,702,279 and 2,255,082.

Suitable zwitteronic surfactants include betaines such alkyl betaines, alkylamidobetaine, amidazoliniumbetaine, sulfobetaine (INCI Sultaines) as well as the phosphobetaine.

Suitable betaines are the alkyl betaines of the formula (Ia), the alkyl amido betaine of the formula (Ib), the sulfo betaines of the formula (Ic) and the amido sulfobetaine of the formula (Id);

R1-N+(CH3)2-CH2COO— (Ia)

R1-CO—NH(CH2)3-N+(CH3)2-CH2COO— (Ib)

R1-N+(CH3)2-CH2CH(OH)CH2SO3- (Ic)

R1-CO—NH—(CH2)3-N+(CH3)2-CH2CH(OH)CH2SO3- (Id)

in which R1 is a saturated or unsaturated C₆-C₂₂alkyl residue, preferably C₈-C₁₈alkyl residue. Particularly preferred are betaines of the formula Ia such as for example N-alkyl-N-dimethyl betaine like the one sold under the trade name of Empigen® BB by Huntsman.

If the composition comprises a zwitterionic surfactant, it is preferably a betaine of the formula Ia such as for example N-alkyl-N-dimethyl betaine like the one sold under the trade name of Empigen BB by Huntsman. It has been found these betaines greatly increase the antibacterial efficacy of the modified amino acids.

Amphoteric surfactants can be either cationic or anionic depending upon the pH of the composition. Suitable amphoteric surfactants include the products sold under the trade name Miranol by Solvay-Novecare such as, for example, sodium lauroamphoacetate (Miranol Ultra L-32E), sodium stearoampho acetate (Miranol DM), disodium cocoamphodiacetate (Miranol C2m Conc NP), disodium lauroamphodiacetate (Miranol BM Conc), disodium capryloampho dipropionate (Miranol JBS), sodium mixed C₈amphocarboxylate (Miranol JEM Conc), and sodium capryloampho hydroxypropyl sulfonate (Miranol JS). Other non-limiting examples of suitable amphoteric surfactants are disodium capryloamphodiacetate (Mackam 2CY 75-Solvay Novecare), octyliminodipropionate (Ampholak YJH40-Akzo Nobel), sodium lauriminodipropionate (Mirataine H2C-HA-Solvay Novecare), and sodium lauroamphohydroxypropylsulfonate (Mackam LS-Solvay Novecare). Amphoteric surfactants might not impact negatively the antimicrobial efficacy of the modify amino acids.

Other suitable additional surfactants can be found in McCutcheon's Detergents and Emulsifiers, North American Ed. 1980.

Cationic Surfactant

The compositions disclosed herein may comprise a cationic surfactant. Non-limiting examples of cationic surfactants include: the quaternary ammonium surfactants, which can have up to 26 carbon atoms and may include alkoxylate quaternary ammonium (AQA) surfactants, dimethyl hydroxyethyl quaternary ammonium, and/or dimethyl hydroxyethyl lauryl ammonium chloride; polyamine cationic surfactants; cationic ester surfactants; amino surfactants, e.g., amido propyldimethyl amine (APA); and mixtures thereof.

Suitable cationic surfactants also may include alkyl pyridinium compounds, alkyl quaternary ammonium compounds, alkyl quaternary phosphonium compounds, alkyl ternary sulphonium compounds, and mixtures thereof.

Suitable cationic detersive surfactants are quaternary ammonium compounds having the general formula:

(R)(R₁)(R₂)(R₃)N⁺X⁻

wherein, R is a linear or branched, substituted or unsubstituted C_6-18alkyl or alkenyl moiety, R₁and R₂are independently selected from methyl or ethyl moieties, R₃is independently selected from a linear or branched, substituted or unsubstituted C_6-18alkyl or alkenyl moiety or a hydroxyl, hydroxymethyl or a hydroxyethyl moiety, X is an anion which provides charge neutrality, suitable anions include: halides, for example chloride; sulphate; and sulphonate. Suitable cationic surfactants are mono-C_6-18alkyl mono-hydroxyethyl di-methyl quaternary ammonium chlorides. Highly suitable cationic surfactants are di-C_8-10alkyl di-methyl quaternary ammonium chloride, mono-C₁₆alkyl tri-methyl quaternary ammonium chloride, di-C_10-12alkyl di-methyl quaternary ammonium chloride and mono-C₁₀alkyl mono-hydroxyethyl di-methyl quaternary ammonium chloride.

Particularly preferred surfactants for use herein include nonionic surfactants, in particular branched alcohol alkoxylates, more in particular 2-ethyl hexan-1-ol ethoxylated to a degree of from 4 to 6, and propoxylated to a degree of from 4 to 6, more preferably, the alcohol is first propoxylated and then ethoxylated, and 2-alkyl-1-alkanols such as alkoxylated C₁₀guerbet alcohols with 1 to 14, preferably 2 to 8, more preferably 3 to 6 ethoxylate or ethoxylate-propoxylate units. Other particularly preferred non-ionic surfactants include linear alcohol alkoxylated nonionic surfactants with C₈, C₁₀, C₁₂, C₁₄mixtures of C₈to C₁₀, mixtures of C₁₀to C₁₂, mixtures of C₁₂to C₁₄, mixtures of C₉to C₁₁linear alkyl chain and 10 or less ethoxylate units, preferably 3 to 9 ethoxylate units. Most preferably the alkoxylated nonionic surfactant is selected from the group consisting of: C₁₂-C₁₄alcohol EO9 (Surfonic L 24-9), 2-propylheptyl EO8 (Lutensol XL89-BASF); 2-propylheptyl EO5 (Lutensol XL50-BASF); Cm alcohol EO5 (Lutensol ON 50-BASF); C₁₀alcohol EO7 (Lutensol ON 70-BASF); C₈-C₁₀alcohol EO5 (Novel 810 FD5 Sasol); C₁₀alcohol EO4 (Novel 10-4 Sasol); and 2-ethyl-hexanol PO5EO6 (Ecosurf EH6-Dow).

Other particularly preferred surfactants for use here in include linear amine oxide surfactants, in particular C₈-C₁₂dimethyl amine oxide, more in particular C₁₀dimethyl amine oxide; alkyldimethylbetaine surfactants, more in particular N,N-Dimethyl-N-dodecylglycine betaine (Empigen BB-Huntsman); alkyl glucamide surfactants such as N-alkyl-N-acylglucamide preferably N-decanoyl-N-methylglucamine, and the alkyl glucamide surfactants sold under the name of GlucoPure®, GlucoTain®, and GlucoWet® by Clariant; alkylpolyglucoside surfactants, more in particular C₈to C₁₂alkyl polyglucosides, more preferably C₈to C₁₀alkyl polyglucosides such as for example Triton CG50 (Dow)

These surfactants improve the antimicrobial activity of the modified amino acid.

Non-Aqueous Solvent

The antimicrobial composition of the present invention comprises a non-aqueous solvent, the solvent comprises carbon, hydrogen and oxygen atoms. Preferred solvents for use herein include glycol ethers, diols and mixtures thereof. Suitable diols to use herein include 1,2-hexane diol, 1,2-octanediol and 1,4 butanediol. Especially preferred for use herein is 1, 4-butanediol. The composition of the invention preferably comprises a glycol ether of Formula 1:

Formula 1=R1O(R2O)nR3

wherein

- R1 is a linear or branched C4, C5 or C6 alkyl, a substituted or unsubstituted phenyl, preferably n-butyl. Benzyl is one of the substituted phenyls for use herein.
- R2 is ethyl or isopropyl, preferably isopropyl
- R3 is hydrogen or methyl, preferably hydrogen
- n is 1, 2 or 3, preferably 1 or 2

Suitable glycol ethers according to Formula 1 include ethyleneglycol n-butyl ether, diethyleneglycol n-butyl ether, triethyleneglycol n-butyl ether, propyleneglycol n-butyl ether, dipropyleneglycol n-butyl ether, tripropyleneglycol n-butyl ether, ethyleneglycol n-pentyl ether, diethyleneglycol n-pentyl ether, triethyleneglycol n-pentyl ether, propyleneglycol n-pentyl ether, dipropyleneglycol n-pentyl ether, tripropyleneglycol n-pentyl ether, ethyleneglycol n-hexyl ether, diethyleneglycol n-hexyl ether, triethyleneglycol n-hexyl ether, propyleneglycol n-hexyl ether, dipropyleneglycol n-hexyl ether, tripropyleneglycol n-hexyl ether, ethyleneglycol phenyl ether, diethyleneglycol phenyl ether, triethyleneglycol phenyl ether, propyleneglycol phenyl ether, dipropyleneglycol phenyl ether, tripropyleneglycol phenyl ether, ethyleneglycol benzyl ether, diethyleneglycol benzyl ether, triethyleneglycol benzyl ether, propyleneglycol benzyl ether, dipropyleneglycol benzyl ether, tripropyleneglycol benzyl ether, ethyleneglycol isobutyl ether, diethyleneglycol isobutyl ether, triethyleneglycol isobutyl ether, propyleneglycol isobutyl ether, dipropyleneglycol isobutyl ether, tripropyleneglycol isobutyl ether, ethyleneglycol isopentyl ether, diethyleneglycol isopentyl ether, triethyleneglycol isopentyl ether, propyleneglycol isopentyl ether, dipropyleneglycol isopentyl ether, tripropyleneglycol isopentyl ether, ethyleneglycol isohexyl ether, diethyleneglycol isohexyl ether, triethyleneglycol isohexyl ether, propyleneglycol isohexyl ether, dipropyleneglycol isohexyl ether, tripropyleneglycol isohexyl ether, ethyleneglycol n-butyl methyl ether, diethyleneglycol n-butyl methyl ether triethyleneglycol n-butyl methyl ether, propyleneglycol n-butyl methyl ether, dipropyleneglycol n-butyl methyl ether, tripropyleneglycol n-butyl methyl ether, ethyleneglycol n-pentyl methyl ether, diethyleneglycol n-pentyl methyl ether, triethyleneglycol n-pentyl methyl ether, propyleneglycol n-pentyl methyl ether, dipropyleneglycol n-pentyl methyl ether, tripropyleneglycol n-pentyl methyl ether, ethyleneglycol n-hexyl methyl ether, diethyleneglycol n-hexyl methyl ether, triethyleneglycol n-hexyl methyl ether, propyleneglycol n-hexyl methyl ether, dipropyleneglycol n-hexyl methyl ether, tripropyleneglycol n-hexyl methyl ether, ethyleneglycol phenyl methyl ether, diethyleneglycol phenyl methyl ether, triethyleneglycol phenyl methyl ether, propyleneglycol phenyl methyl ether, dipropyleneglycol phenyl methyl ether, tripropyleneglycol phenyl methyl ether, ethyleneglycol benzyl methyl ether, diethyleneglycol benzyl methyl ether, triethyleneglycol benzyl methyl ether, propyleneglycol benzyl methyl ether, dipropyleneglycol benzyl methyl ether, tripropyleneglycol benzyl methyl ether, ethyleneglycol isobutyl methyl ether, diethyleneglycol isobutyl methyl ether, triethyleneglycol isobutyl methyl ether, propyleneglycol isobutyl methyl ether, dipropyleneglycol isobutyl methyl ether, tripropyleneglycol isobutyl methyl ether, ethyleneglycol isopentyl methyl ether, diethyleneglycol isopentyl methyl ether, triethyleneglycol isopentyl methyl ether, propyleneglycol isopentyl methyl ether, dipropyleneglycol isopentyl methyl ether, tripropyleneglycol isopentyl methyl ether, ethyleneglycol isohexyl methyl ether, diethyleneglycol isohexyl methyl ether, triethyleneglycol isohexyl methyl ether, propyleneglycol isohexyl methyl ether, dipropyleneglycol isohexyl methyl ether, tripropyleneglycol isohexyl methyl ether, and mixtures thereof.

Preferred glycol ether solvents according to Formula 1 are ethyleneglycol n-butyl ether, diethyleneglycol n-butyl ether, triethyleneglycol n-butyl ether, propyleneglycol n-butyl ether, dipropyleneglycol n-butyl ether, tripropyleneglycol n-butyl ether, and mixtures thereof.

The most preferred glycol ether for use herein are selected from is the group consisting of of diethylene glycol butyl ether, di(propylene glycol) methyl ether and mixtures thereof.

The composition of the invention preferably comprises from about 0.1% to about 10%, more preferably from about 0.2 to about 6% by weight of the composition of the glycol ether, more preferably from about 0.2 to about 3% by weight of the composition of diethylene glycol butyl ether, di(propylene glycol) methyl ether and mixtures thereof.

Antimicrobial Agent

The antimicrobial composition of the invention comprises an antimicrobial agent. The antimicrobial agent comprises a modified amino acid. The amino acid is selected from the group consisting of alanine, valine, isoleucine, leucine, methionine, tyrosine, phenylalanine and tryptophan. The amino acid has been modified by replacing the c-terminus oxygen atom by a nitrogen atom, creating an amide, with said nitrogen atom being attached to a hydrocarbon moiety. The hydrocarbon moiety may be selected to increase the overall hydrophobicity of the resulting compound, which is believed to improve the antimicrobial efficacy.

The antimicrobial agent of the composition of the invention comprises an antimicrobial agent comprising a compound according to Formula I,

[Image Omitted]

wherein R1 is the side group of a protogenic amino acid, the amino acid is selected from the group consisting of alanine (—CH₃), valine (—CH(CH₃)₂), phenylalanine (—CH₂C₆H₅), methionine (CH₂CH₂SCH₃), tyrosine (CH₂(p-C₆H₄—OH)), isoleucine (CH(CH₃)CH₂CH₃), leucine (CH₂CH(CH₃)₂) and tryptophan

[Image Omitted]

Preferably R¹is selected from phenylalanine, tyrosine and tryptophan. R²represents a hydrocarbon moiety having from 4 to 10 carbon atoms and preferably R²is bound to the nitrogen atom (N) by a CH₂moiety. R³is independently selected from H or a hydrocarbon moiety having from 4 to 10 carbon atoms, preferably R3 is H. Specially preferred antimicrobial agents for use in the composition of the invention comprise compounds of formula I in which R1 is selected from —CH₂C₆H₅, CH₂(p-C₆H₄—OH) and

[Image Omitted]

Specially preferred antimicrobial agents for use in the composition of the invention comprise compounds of formula I in which R2 is bound to the nitrogen atom (N) by a CH₂moiety and the hydrocarbon moiety has from 4 to 10 carbon atoms, more preferably R₂from 6 to 10 and specially 8 carbon atoms.

Specially preferred are antimicrobial agents of formula I in which R1 is selected from —CH₂C₆H₅, CH₂(p-C₆H₄—OH) and

[Image Omitted]

and in which R2 is bound to the nitrogen atom (N) by a CH₂moiety and the hydrocarbon moiety has from 6 to 10 and specially 8 carbon atoms and R3 is H.

Preferably, the compound of Formula I has a log P of from about 1.5 to about 6.0, preferably from about 2.0 to about 5.0 as calculated using the Consensus log P Computational Model, version 14.5 (Linux). Compositions comprising compounds of Formula I with a log P of from about 1.5 to about 6.0, preferably from about 2.0 to about 5.0 provide good antimicrobial benefits.

Other Optional Ingredients
Chelating Agent

The antimicrobial composition can comprise a chelating agent. Suitable chelating agents, in combination with the surfactant system, improve the shine benefit. Chelating agent can be incorporated into the compositions in amounts ranging from 0.02% to 5.0%, preferably from 0.1% to 3.0%, more preferably from 0.2% to 2.0% and most preferably from 0.2% to 0.4% by weight of the composition.

Suitable phosphonate chelating agents include ethylene diamine tetra methylene phosphonates, and diethylene triamine penta methylene phosphonates (DTPMP), and can be present either in their acid form or as salts.

A preferred biodegradable chelating agent for use herein is ethylene diamine N,N′-disuccinic acid, or alkali metal, or alkaline earth, ammonium or substitutes ammonium salts thereof or mixtures thereof. A more preferred biodegradable chelating agent is L-glutamic acid N,N-diacetic acid (GLDA) commercially available under tradename Dissolvine 47S from Akzo Nobel.

Suitable amino carboxylates include ethylene diamine tetra acetates, diethylene triamine pentaacetates, diethylene triamine pentaacetate (DTPA), N-hydroxyethylethylenediamine triacetates, nitrilotriacetates, ethylenediamine tetrapropionates, triethylenetetraaminehexa-acetates, ethanoldiglycines, and methyl glycine diacetic acid (MGDA), both in their acid form, or in their alkali metal, ammonium, and substituted ammonium salt forms. Particularly suitable amino carboxylate to be used herein is propylene diamine tetracetic acid (PDTA) which is, for instance, commercially available from BASF under the trade name Trilon FS® and methyl glycine di-acetic acid (MGDA). Most preferred aminocarboxylate used herein is diethylene triamine pentaacetate (DTPA) from BASF. Further carboxylate chelating agents for use herein include salicylic acid, aspartic acid, glutamic acid, glycine, malonic acid or mixtures thereof.

Suitable polycarboxylates include itaconic acid and sodium polyitaconate which is, for instance, commercially available from Itaconix under the trade name of Itaconix® DSP 2K™, and Itaconix® CHT121™.

Polymers

The antimicrobial composition may comprise an additional polymer. It has been found that the presence of a specific polymer as described herein, when present, allows further improving the grease removal performance of the composition due to the specific sudsing/foaming characteristics they provide to the composition. Suitable polymers for use herein are disclosed in EP2272942 and EP2025743.

The polymer can be selected from the group consisting of: a vinylpyrrolidone homopolymer (PVP); a polyethyleneglycol dimethylether (DM-PEG); a vinylpyrrolidone/dialkylaminoalkyl acrylate or methacrylate copolymers; a polystyrenesulphonate polymer (PSS); a poly vinyl pyridine-N-oxide (PVNO); a polyvinylpyrrolidone/vinylimidazole copolymer (PVP-VI); a polyvinylpyrrolidone/polyacrylic acid copolymer (PVP-AA); a polyvinylpyrrolidone/vinylacetate copolymer (PVP-VA); a poly acrylic polymer or polyacrylicmaleic copolymer; and a polyacrylic or polyacrylic maleic phosphono end group copolymer; and mixtures thereof.

Typically, the antimicrobial composition may comprise from 0.005% to 5.0%, preferably from 0.10% to 4.0%, more preferably from 0.1% to 3.0% and most preferably from 0.20% to 1.0% by weight of the composition of said polymer.

Thickener

The antimicrobial composition of the invention can further comprise a thickener. Suitable thickeners herein include polyacrylate based polymers, preferably hydrophobically modified polyacrylate polymers; amide polymers; hydroxyl ethyl cellulose, preferably hydrophobically modified hydroxyl ethyl cellulose, xanthan gum, hydrogenated castor oil (HCO) and mixtures thereof.

Other Optional Ingredients

The composition of the invention may comprise a variety of other optional ingredients depending on the technical benefit aimed for and the surface treated. Suitable optional ingredients for use herein include perfume, builders, other polymers, buffers, hydrotropes, colorants, stabilisers, radical scavengers, abrasives, soil suspenders, brighteners, anti-dusting agents, dispersants, dye transfer inhibitors, pigments, silicones and/or dyes.

A preferred composition according to the invention comprises

- a) from 0.01% to 5% by weight of the composition of a non-ionic surfactant selected from the group consisting of alkyl polyglucoside, alkoxylated alcohol and mixtures thereof;
- b) from 0.01% to 10% by weight of the composition of a solvent selected from the group consisting of diethylene glycol butyl ether, di(propylene glycol) methyl ether and mixtures thereof;
- c) from 0.001 to 1% by weight of the composition of an antimicrobial agent selected from the group consisting of compounds of Formula I wherein the compound of Formula I has a log P of from about 1.5 to about 6.0, preferably from about 2.0 to about 5.0 as calculated using the Consensus log P Computational Model, version 14.5 (Linux);
- d) at least 50% by weight of the composition of water; and wherein the composition has a pH less than or equal to 7, preferably from pH 2 to 7 as measured at 25° C.
  
  A preferred composition according to the invention comprises
- a) from 0.01% to 5% by weight of the composition of a non-ionic surfactant comprising an alkoxylated alcohol comprising from 6 to 16 carbon atoms and from 2 to 12 alkoxy groups, preferably from 4 to 10 ethoxy groups; or a branched ethoxylated propoxylated alcohol;
- b) from 0.01% to 10% by weight of the composition of a solvent is selected from the group consisting of glycol ethers, diols and mixtures thereof;
- c) from 0.001 to 1% by weight of the composition of an antimicrobial agent selected from the group consisting of compounds of Formula I wherein:
  - i) R¹is selected from CH₂(p-C₆H₄—OH),

[Image Omitted]

- and CH₂C₆H₅and R²is a carbon chain comprising 8 carbon atoms and R3 is H;
- d) from 85% to 98% by weight of the composition of water; and
  - wherein the composition has a pH less than or equal to 7, preferably a pH from 2 to 7 as measured at 25° C.
    
    A preferred composition according to the invention comprises
- a) from 0.01% to 5% by weight of the composition of a non-ionic surfactant selected from the group consisting of alkyl polyglucoside, alkoxylated alcohols and mixtures thereof;
- b) from 0.01% to 10% by weight of the composition of a solvent is selected from the group consisting of diethylene glycol butyl ether, di(propylene glycol) methyl ether and mixtures thereof;
- c) from 0.001 to 1% by weight of the composition of an antimicrobial agent selected from the group consisting of compounds of Formula I wherein:
  - i) R¹is selected from CH₂(p-C₆H₄—OH),

[Image Omitted]

- and CH₂C₆H₅and R²is a carbon chain comprising 8 carbon atoms and R3 is H;
- d) from 85% to 98% by weight of the composition of water; and
  - wherein the composition has a pH less than or equal to 7, preferably a pH from 2 to 7 as measured at 25° C.

Wipe

The present invention also relates to an article treated with the composition of the invention. The article is preferably a wipe. Suitable wipes can be fibrous. Suitable fibrous wipes can comprise polymeric fibres, cellulose fibres, and combinations thereof. Suitable cellulose-based wipes include kitchen wipes, and the like. Suitable polymeric fibres include polyethylene, polyester, and the like. Polymeric fibres can be spun-bonded to form the wipe. Methods for preparing thermally bonded fibrous materials are described in U.S. application Ser. No. 08/479,096 (see especially pages 16-20) and U.S. Pat. No. 5,549,589 (see especially Columns 9 to 10). Suitable pads include foams and the like, such as HIPE-derived hydrophilic, polymeric foam. Such foams and methods for their preparation are described in U.S. Pat. No. 5,550,167; and U.S. patent application Ser. No. 08/370,695.

The load factor is defined as the weight ratio of antimicrobial solution to nonwoven substrate is preferably from about 3× to about 10×. Preferably, the load factor is between 4× and 8×, or from 4.5× to 7.5×, or from 5× to 7×. It is found that higher load factors for the pre-moistened wipes of the invention are preferable since they help increase product mileage.

Method of Cleaning a Surface

The composition of the invention is particularly suited for cleaning of inanimate surfaces preferably selected from the group consisting of: ceramic, enamel, stainless steel, Inox®, Formica®, vinyl, no-wax vinyl, linoleum, melamine, glass, plastics and plastified wood, and combinations thereof. In particular, the compositions are particularly suited for reducing the microbial population, while leaving surfaces clean, shiny and grease free.

The compositions described herein can be used neat or can be achieved by diluting with water a concentrated composition prior to applying to the surface. In preferred methods, the composition is applied neat, more preferably, the hard surface cleaning composition is sprayed onto the hard surface.

The composition can be applied by any suitable means, including using a mop, sponge, cloth, paper towel, or other suitable implement.

The surface may be rinsed, preferably with clean water, in an optional further step, and also as a further step, wiped, such as with a cloth or a paper towel.

In another preferred embodiment of the present invention said method of cleaning an inanimate surface includes the steps of applying, preferably spraying, said liquid composition onto said surface, leaving said liquid composition to act onto said surface for a period of time with or without applying mechanical action, and optionally removing said liquid composition, preferably removing said liquid composition by rinsing said hard surface with water and/or wiping said hard surface with an appropriate implement, e.g., a sponge, a paper or cloth towel and the like. Such compositions are often referred to as “ready-to-use” compositions. In preferred methods, the surface is a hard surface. Preferably the surface is not rinsed after application of the antimicrobial composition.

It is believed that antimicrobial compositions comprising specific surfactants, non-aqueous solvents and the modified amino acid of Formula I deliver very good antimicrobial efficacy at very low levels of antimicrobial agent. The antimicrobial composition of the present invention exhibits improved antimicrobial efficacy, good grease cleaning and/or streak-free shine.

Test Methods
pH Measurement

The pH is measured on the neat composition, at 25° C., using a pH meter with compatible gel-filled pH probe (such as Sartarius PT-10P meter with Toledo probe part number 52 000 100), calibrated according to the instruction manual.

Test Method for Determining Log P

The value of the log of the Octanol/Water Partition Coefficient (log P) is computed for a modified amino acid material as described here.

The log P of an individual material is calculated using the Consensus log P Computational Model, version 14.5 (Linux) available from Advanced Chemistry Development Inc. (ACD/Labs) (Toronto, Canada) to provide the unitless log P value. The ACD/Labs' Consensus log P Computational Model is part of the ACD/Labs model suite.

Surface Antimicrobial Kill Testing Method

Inoculum is prepared by streaking microorganism onto a Tryptic Soy Agar (TSA) plate and incubating for 24 h at 33° C. Plated bacteria is resuspended in saline until the transmittance percentage falls within the accepted range for ˜10⁸cfu/mL. For K. pneumonia (Kp) and P. aeruginosa (Pa), this is 31.00-33.00% T. For S. aureus (Sa) this is 23.00-25.00% T. A 10× concentration is made by spinning down the prepared inoculum, removing the supernatant saline from the bacterial pellet, then resuspending the pellet in 1/10th of the original volume of saline. The final inoculum is prepared with 5% of “soil” in the form of Fetal Bovine Serum (FBS).

A 18×18 mm sterile glass coverslip is placed into an appropriate container (e.g., petri dish). 20 μL of prepared inoculum is added to the glass coverslip. Inoculum is then air-dried for 30 minutes in a 36° C. incubator. After drying, 40 μL of test sample is added on top of the dried inoculum. This is incubated at room temperature for the desired contact time. 5 mL of neutralizing media (Modified Letheen Broth+Tween+Lecithin (MLBTL)) is added to the coverslip and shaken on an orbital shaker for 5 minutes to ensure proper neutralization and extraction. Viability is then assessed of the neutralized and extracted sample by traditional/alternative microbiological techniques.

Normalization of Antimicrobial Activity Method

The normalized antimicrobial activity reported in the performance examples below was generated from detection time data obtained as described in the Surface Antimicrobial Kill Test Method. To account for day-to-day variability an internal standard was tested with each series. The internal standard was a composition of 0.25 wt % Triclosan, Sigma Aldrich (St. Louis, MO, USA; CAS #3380-34-5, 97.0-103.0% (active substance, GC)), 50 wt % DMSO, and 49.75 wt % H₂O, with a final solution pH of 7.7. Normalized activity is reported following the equation 1 below.

Normalized Activity=(αΔDT−βΔDT)/(γΔDT−βΔDT) equation 1.

where, αΔDT is the average detection time of the antimicrobial compound, and γΔDT is the average detection time of the reference triclosan internal standard, and βΔDT is the average detection time of the background unperturbed bacteria.

Formulation Method for Surface Kill Testing

Modified amino acids of the present disclosure were tested as aqueous solutions in the Surface Antimicrobial Kill Testing Method above. To prepare test solutions modified amino acids were first dissolved in the appropriate solvent. Second the selected surfactant is added to the mixture. After vortex (1 min, Vortex-2 Genie, vortex speed 8) mixing, the samples were then diluted with ½ portion of reverse osmosis water (RO water, Millipore Direct-Q™, pH 6). The aqueous solution was then vortexed (1 min, Vortex-2 Genie, vortex speed 8), to which the second ½ portion of water is added. The pH of the solution was then adjusted to the target pH using either 1N HCl, Glacial Acetic Acid, or 1N NaOH. The final solution was then vortexed (1 min, Vortex-2 Genie, vortex speed 8). An example batch sheet is provided below in Table 1.

Surfactant description and vender: Tween® 80 (Sigma Aldrich, St. Louis, MO, USA), Plantaren® 2000 N UP (BASF, Florham Park, NJ, USA), EcoSurf™ EH6 (Sigma Aldrich, St. Louis, MO, USA), EcoSurf™ EH9 (Sigma Aldrich, St. Louis, MO, USA), Surfonic® L24-9 (Huntsman Holland BV, Botlek-Rotterdam, Netherlands), Miranol® Ultra L-32 (Solvay S.A., Brussels, Belgium), Cetyltrimethylammonium chloride (CTAC, 25 wt % in H2O, Sigma Aldrich, St. Louis, MO, USA), Sodium Lauryl Sulfate (SLS, 29 wt % in H2O, Stepan, Northfield, IL, USA), Tergitol™ TMN-6 (Sigma Aldrich, St. Louis, MO, USA), C₁₀dimethyl amine oxide is commercially available under the trade name Genaminox® K-10 from Clariant.

Solvents and vender: 1,4-Butanediol (99%, Sigma Aldrich, St. Louis, MO, USA), Ethylene Glycol (99%, Sigma Aldrich, St. Louis, MO, USA), Diethylene glycol mono-n-butyl ether (99%, DEGBE, Thermo Fisher Scientific, Ward Hill, MA, USA), Di(propylene glycol)methyl ether, mixture of isomers (99%, DPGME, Sigma Aldrich, St. Louis, MO, USA), Dimethyl sulfoxide (99%, DMSO, Sigma Aldrich, St. Louis, MO, USA), Hexylene Glycol (99%, Sigma Aldrich, St. Louis, MO, USA), 2-Phenoxyethanol (99%, Sigma Aldrich, St. Louis, MO, USA), Di(ethylene glycol) hexyl ether (95%, Sigma Aldrich, St. Louis, MO, USA).

TABLE 1

Illustrative formulation sheet for modified amino acids

solutions for surface antimicrobial kill testing.

Ingredients
Quantity (g)

Amino Acid Active (g)
0.1
g

EcoSurf EH-9 (g)
0.2
g

DEGBE (g)
1.0
g

Reverse Osmosis Water (g)
18.7
g

Total Batch Size
20.00

TABLE 2

Illustrative formulation sheet for modified amino acids

solutions for surface antimicrobial kill testing.

Ingredients
Quantity (g)

Amino Acid Active (g)
0.1
g

EcoSurf EH-9 (g)
0.2
g

Hexylene Glycol (g)
1.0
g

Reverse Osmosis Water (g)
18.7
g

Total Batch Size
20.00

TABLE 3

Illustrative formulation sheet for modified amino acids

solutions for surface antimicrobial kill testing.

Ingredients
Quantity (g)

Amino Acid Active (g)
0.1
g

Surfonic L 24-9 (g)
0.2
g

Ethylene Glycol
1.0
g

Reverse Osmosis Water (g)
18.7
g

Total Batch Size
20.00

TABLE 4

Illustrative formulation sheet for modified amino acids

solutions for surface antimicrobial kill testing.

Ingredients
Quantity (g)

Amino Acid Active (g)
0.1
g

Tergitol TMN-6 (g)
0.2
g

Di(ethylene glycol) hexyl ether (g)
1.0
g

Reverse Osmosis Water (g)
18.7
g

Total Batch Size
20.00

TABLE 5

Illustrative formulation sheet for modified amino acids

solutions for surface antimicrobial kill testing.

Ingredients
Quantity (g)

Amino Acid Active (g)
0.1
g

EcoSurf EH-6 (g)
0.2
g

2-Phenoxyethanol (g)
1.0
g

Reverse Osmosis Water (g)
18.7
g

Total Batch Size
20.00

TABLE 6

Illustrative formulation sheet for modified amino acids

solutions for surface antimicrobial kill testing.

Ingredients
Quantity (g)

Amino Acid Active (g)
0.1
g

Surfonic L 24-9 (g)
0.2
g

2-Phenoxyethanol (g)
0.2
g

DPGME
0.8
g

Reverse Osmosis Water (g)
18.7
g

Total Batch Size
20.00

TABLE 7

Illustrative formulation sheet for modified amino acids

solutions for surface antimicrobial kill testing.

Ingredients
Quantity (g)

Amino Acid Active (g)
0.1
g

Genaminox ® K-10 (g)
0.1
g

DEGBE
1.0
g

Reverse Osmosis Water (g)
18.8
g

Total Batch Size
20.00

TABLE 8

Illustrative formulation sheet for modified amino acids

solutions for surface antimicrobial kill testing.

Ingredients
Quantity (g)

Amino Acid Active (g)
0.1
g

Didecyldimethylammonium chloride
0.1
g

DEGBE
1.0
g

Reverse Osmosis Water (g)
18.8
g

Total Batch Size
20.00

TABLE 9

Illustrative formulation sheet for modified amino acids

solutions for surface antimicrobial kill testing.

Ingredients
Quantity (g)

Amino Acid Active (g)
0.1
g

Surfonic L 24-9
0.1
g

Tween 80
0.1
g

DEGBE
1.0
g

Reverse Osmosis Water (g)
18.7
g

Total Batch Size
20.00

TABLE 10

Illustrative formulation sheet for modified amino acids

solutions for surface antimicrobial kill testing.

Ingredients
Quantity (g)

Amino Acid Active (g)
0.05
g

EcoSurf EH-9 (g)
0.1
g

DEGBE (g)
0.5
g

Reverse Osmosis Water (g)
19.35
g

Total Batch Size
20.00

SYNTHESIS & COMPARATIVE EXAMPLES
Methods of Preparing Antimicrobial Compounds (e.g., Modified Amino Acid Amides)

In the following synthesis examples, the materials are generally obtained/available from Sigma-Aldrich (St. Louis, MO, USA), except as indicated below. The amino acids are generally provided at >98% or even >99% purity. Amines are generally provided at >95% or even >99% purity (St. Louis, MO, USA).

General Method A: To a round bottom flask is added 3 equiv. of an alkyl amine and 1 equiv. of a free base amino acid starting material. The mixture is then diluted with tert-amyl methyl ether and fitted with a Dean-Stark apparatus. To the gently refluxing mixture is added 1 equiv. of B(OCH₂CF₃)₃. A West condenser was fitted, and the reaction mixture stirred for 24 to 72 hours. Upon completion, the reaction mixture was concentrated in vacuo and dry loaded onto silica gel for column chromatography eluting with a DCM:MeOH mixture. The combined fractions were then recrystallized from Et₂O.

General Method B: As described above for Method A, but with 1 equiv. of Ti(OiPr)₄instead of B(OCH₂CF₃)₃.

Synthetic Example 1

As according to method A, a stirred suspension of hexylamine (4.9 g, 48.5 mmol) and L-Tryptophan (3.3 g, 16.2 mmol) in tert-amyl methyl ether (TAME, 50 mL) with a Dean-Stark was heated to reflux and 1 equiv. of B(OCH₂CF₃)₃(5.0 g, 16.2 mmol) was added through the Dean-Stark. A West condenser was fitted, and the reaction mixture stirred for 24 hours under N₂. Upon completion, the reaction mixture was concentrated in vacuo and dry loaded onto silica gel for column chromatography. After purification 1 was obtained as a powdery white solid.

Synthetic Example 2

As according to method B, a stirred suspension of octylamine (2.9 g, 22.0 mmol) and L-Tryptophan (1.5 g, 7.4 mmol) in tert-amyl methyl ether (TAME, 50 mL) with a Dean-Stark was heated to reflux and 1 equiv. of Ti(OiPr)₄(3.1 g, 11.0 mmol) was added through the Dean-Stark. A West condenser was fitted, and the reaction mixture stirred for 24 hours under N₂. Upon completion, the reaction mixture was concentrated in vacuo and dry loaded onto silica gel for column chromatography. After purification 2 was obtained as a powdery white solid.

Synthetic Example 3

As according to method B, a stirred suspension of nonylamine (3.2 g, 22.0 mmol) and L-Tryptophan (1.5 g, 7.4 mmol) in tert-amyl methyl ether (TAME, 50 mL) with a Dean-Stark was heated to reflux and 1 equiv. of Ti(OiPr)₄(3.1 g, 11.0 mmol) was added through the Dean-Stark. A West condenser was fitted, and the reaction mixture stirred for 24 hours under N₂. Upon completion, the reaction mixture was concentrated in vacuo and dry loaded onto silica gel for column chromatography. After purification 3 was obtained as a powdery white solid.

Synthetic Example 4

As according to method B, a stirred suspension of octylamine (32.1 g, 248.4 mmol) and L-Tyrosine (15.0 g, 82.8 mmol) in tert-amyl methyl ether (TAME, 50 mL) with a Dean-Stark was heated to reflux and 1 equiv. of Ti(OiPr)₄(47.1 g, 165.6 mmol) was added through the Dean-Stark. A West condenser was fitted, and the reaction mixture stirred for 24 hours under N₂. Upon completion, the reaction mixture was concentrated in vacuo and dry loaded onto silica gel for column chromatography. After purification 4 was obtained as a powdery white solid.

Synthetic Example 5

As according to method B, a stirred suspension of octylamine (23.5 g, 181.6 mmol) and L-phenylalanine (10.0 g, 60.5 mmol) in tert-amyl methyl ether (TAME, 50 mL) with a Dean-Stark was heated to reflux and 1 equiv. of Ti(OiPr)₄(18.9 g, 66.6 mmol) was added through the Dean-Stark. A West condenser was fitted, and the reaction mixture stirred for 24 hours under N₂. Upon completion, the reaction mixture was concentrated in vacuo and dry loaded onto silica gel for column chromatography. After purification 2 was obtained as a powdery white solid.

Synthetic Example 6

Synthetic Example 6 was purchased from Sigma Aldrich (St. Louis, MO, USA) and used directly.

Synthetic Example 7

As according to method B, a stirred suspension of dodecylamine (33.7 g, 181.6 mmol) and L-phenylalanine (10.0 g, 60.5 mmol) in tert-amyl methyl ether (TAME, 50 mL) with a Dean-Stark was heated to reflux and 1 equiv. of Ti(OiPr)₄(18.9 g, 66.6 mmol) was added through the Dean-Stark. A West condenser was fitted, and the reaction mixture stirred for 24 hours under N₂. Upon completion, the reaction mixture was concentrated in vacuo and dry loaded onto silica gel for column chromatography. After purification 7 was obtained as a powdery white solid.

Structures of the Synthetic Examples

Table 11 below illustrates the structures of the Synthetic Examples 1-7. Calculated log P values for the total molecule are provided and were obtained using the Test Method for Determining log P described above.

TABLE 11

Structural representation and logP values of the Synthesis Examples.

Structures of the Synthetic Examples.

No.
Modified Amino Acid
logP

1

[Image Omitted]

2.9

2

[Image Omitted]

4.1

3

[Image Omitted]

5.0

4

[Image Omitted]

4.9

5

[Image Omitted]

3.8

6

[Image Omitted]

2.7

7

[Image Omitted]

6.1

Table 12 below illustrates the structure of Comparative Example C1. Calculated log P value for the total molecule is provided and was obtained using the Test Method for Determining log P described above. The comparative sample C1 was purchased and used as received from Sigma Aldrich (St. Louis, MO, USA).

TABLE 12

Structural representation and logP values of the Comparative Examples.

No.
Modified Amino Acid
logP

C1

[Image Omitted]

0.6

PERFORMANCE EXAMPLES

In Performance Examples 1-5 below, formulations comprising solvent, surfactant, and antimicrobial agents according to the present disclosure (e.g., based on modified amino acid amides), are evaluated via microbial surface kill tests according to the Surface Antimicrobial Kill Testing Method provided above. After treatment, microbial growth is referenced and reported to a triclosan sample and unaltered microbes according to the Normalization of Antimicrobial Activity provided above. Therefore, values greater than one would be more active above the internal triclosan control, with values less than one but greater than zero still having antimicrobial activity. The data below shows the benefits afforded by hydrophobically modified amino acids.

Performance Example 1. Antimicrobial Efficacy of Aged Amide Formulas of Tryptophan

Results of Antimicrobial Surface Testing are provided below in Table 1.

Gram Positive

Antimicrobial

Referenced

Compound
Aged
Surfactant
Microbial

(0.5 wt %)^α
Samples
(1 wt %)
Activity

1
Synthetic
—
Surfonic L 24-9
1.0

Example 2

2
Synthetic
14 days
Surfonic L 24-9
1.1

Example 2

^αContaining 5 wt % DPGME and remaining wt % fraction composed of water, where the final formulas are adjusted to pH 4.5 using either HCl or NaOH.

As shown in Table 1, amides demonstrate good stability over time.

Performance Example 2. Examination of Alkyl Substitution of Amides on the Antimicrobial Efficacy of Modified Phenylalanine Solutions

TABLE 2A

Materials
R²and R³alkyl groups
LogP of total Molecule

Competitive Example C1

[Image Omitted]

0.6

Synthetic Example 5

[Image Omitted]

3.8

Synthetic Example 6

[Image Omitted]

2.7

Synthetic Example 7

[Image Omitted]

6.1

Results of Antimicrobial Surface Testing are provided below in Table 2B.

Gram Negative
Gram Positive

Antimicrobial

Referenced
Referenced

Compound
Solvent
Surfactant
Microbial
Microbial

(0.5 wt %)^α
(5 wt %)
(1 wt %)
Activity
Activity

1
—
DPGME
Surfonic L24-9
−0.1
0.1

2
Comparative Example C1
DPGME
Surfonic L24-9
0.2
0.1

3
Synthetic Example 5
DPGME
Surfonic L24-9
≥3.9
0.7

4
Synthetic Example 6
DPGME
Surfonic L24-9
2.7
0.2

5
Synthetic Example 7
DPGME
Surfonic L24-9
0.1
0.1

^αRemaining wt % fraction composed of 0.1M Acetic acid buffer pH 4.5.

Table 2B illustrates examples of both secondary and tertiary amides providing an antimicrobial benefit. However, chain length and conformational structure may be more vital for driving antimicrobial efficacy. For example, the short alkyl chain of Comparative Example C1 and the long alkyl chain of Synthetic Example 7 fail to show any meaningful benefit. Synthetic Example 5 and 6, both containing a total of eight carbons, demonstrate meaningful gram-negative activity. Synthetic Example 5 with eight linear carbons shows improvement against gram-negative and gram-positive bacteria.

Performance Example 3. Examination of Alkyl Chain Length of Amides on the Antimicrobial Efficacy of Modified Tryptophan Solutions

TABLE 3A

Materials
R3 is H, R²alkyl group

Synthetic Example 1

[Image Omitted]

Synthetic Example 2

[Image Omitted]

Synthetic Example 3

[Image Omitted]

Results of Antimicrobial Surface Testing are provided below in Table 3B.

Gram Negative
Gram Positive

Antimicrobial

Referenced
Referenced

Compound
Solvent
Surfactant
Microbial
Microbial

(0.5 wt %)^α
(5 wt %)
(1 wt %)
Activity
Activity

1
—
DPGME
Surfonic L24-9
−0.1
0.1

3
Synthetic Example 1
DPGME
Surfonic L24-9
2.2
0.3

4
Synthetic Example 2
DPGME
Surfonic L24-9
2.5
1.0

5
Synthetic Example 3
DPGME
Surfonic L24-9
2.2
0.3

^αRemaining wt % fraction composed of 0.1M Acetic acid buffer pH 4.5.

As demonstrated in Table 3B, each of the synthetic examples show improved activity over the control solution. From this study the most preferred chain length for the exemplified formulas may be about eight carbons.

Performance Example 4. Examination of Surfactant on Surface Antimicrobial Efficacy of Synthetic Example 2 Formulas

Results of Antimicrobial Surface Testing are provided below in Table 4.

Gram Negative
Gram Positive

Referenced
Referenced

pH of
Surfactant
Microbial
Microbial

Formula
(1 wt %)
Activity
Activity

1
4.5
Surfonic L24-9
2.5
1.0

2
4.5
EH6
≥4.9
1.6

3
4.5
Tween 80
≥4.9
1.2

4
4.5
Plantaren 2000
≥4.9
1.3

5
4.5
Miranol Ultra
≥4.9
0.7

6
9
Surfonic L24-9
0.7
0.2

7
9
Miranol Ultra
0.1
0.2

8
9
SLS
0.0
0.2

^αContaining 5 wt % DPGME, Synthetic Example 2 at 0.5 wt %, and the remaining wt % fraction composed of water, where the final formulas is adjusted to the reported pH using either HCl or NaOH.

Synthetic Example 2 shows antimicrobial efficacy for both gram-negative and gram-positive bacteria with a variety of surfactants. A cutoff at pH 9 is observed for Synthetic example 2.

The dimensions and values disclosed herein are not to be understood as being strictly limited to the exact numerical values recited. Instead, unless otherwise specified, each such dimension is intended to mean both the recited value and a functionally equivalent range surrounding that value. For example, a dimension disclosed as “40 mm” is intended to mean “about mm.”

Every document cited herein, including any cross referenced or related patent or application and any patent application or patent to which this application claims priority or benefit thereof, is hereby incorporated herein by reference in its entirety unless expressly excluded or otherwise limited. The citation of any document is not an admission that it is prior art with respect to any invention disclosed or claimed herein or that it alone, or in any combination with any other reference or references, teaches, suggests or discloses any such invention. Further, to the extent that any meaning or definition of a term in this document conflicts with any meaning or definition of the same term in a document incorporated by reference, the meaning or definition assigned to that term in this document shall govern.

While particular embodiments of the present invention have been illustrated and described, it would be obvious to those skilled in the art that various other changes and modifications can be made without departing from the spirit and scope of the invention. It is therefore intended to cover in the appended claims all such changes and modifications that are within the scope of this invention.