Multifunctional boosters for antimicrobial preservatives and applications thereof

Abstract

The present disclosure relates to certain ether compounds as described herein as new multifunctional boosters for enhancing the activity of antimicrobial preservatives and applications thereof in personal care products, cosmetic products and home care products.

Description

[0001] TITLE

[0002] Multifunctional Boosters for Antimicrobial Preservatives and Applications Thereof

[0003] FIELD OF INVENTION

[0004] The present invention relates generally to multifunctional boosters to enhance the antimicrobial activity of antimicrobial preservatives and applications thereof in personal care products, cosmetic products and home care products, and, more particularly, to certain ether compounds as such multifunctional boosters.

[0005] BACKGROUND OF THE INVENTION

[0006] Protection against microbial contamination of personal care products, cosmetic products, and home care products is of high importance to these product industries. Traditional preservatives, such as isothiazolinones, formaldehyde releasers, parabens, and IPBC, are under increased scrutiny from regulatory agencies and environmental working groups. In many cases, product formulators are seeking solutions to reduce the dosing levels of traditional preservatives without compromising the level of preservation. Many product formulators are also turning to soft preservatives, such as phenoxyethanol, alcohols and / or organic acids. Because soft preservatives alone often do not provide robust full-spectrum antimicrobial efficacy, particularly at desired dosing levels, formulators may use them in combination with booster compounds to provide more robust protection to product compositions. Furthermore, there is an increased demand for product formulations that provide multiple benefits in one product or product application.

[0007] There is a need to provide booster compounds that enhance the antimicrobial efficacy of antimicrobial preservatives in personal care, cosmetic and home care product compositions, thereby decreasing the number and / or concentration of antimicrobial preservatives otherwise required to achieve sufficient protection. Further, there is a need to provide compounds with multifunctional benefits, such as antioxidant, surfactant, humectant and / or chelating properties, allowing formulators to prepare products with reduced numbers and / or amounts of ingredients without compromising (and potentially even enhancing) the benefit of the end product.

[0008] Certain ether compounds have been disclosed for use in antimicrobial compositions.

[0009] WO 2014 / 191258A2 is directed to antimicrobial compositions comprising certain glyceryl ethers, and WO 2022 / 128882A1 is directed to a combination of n-heptyl-glyceryl ether and certain preservative compounds. These references do not disclose the allyl ether compounds of formula (I) of the present disclosure, the present compounds’ enhancement of the activity of antimicrobial preservatives or their multifunctional properties, as described herein.

[0010] In accordance with the present disclosure, it was discovered that the ether compounds of formula (I) as disclosed herein act as boosters to enhance the antimicrobial activity of antimicrobial preservatives, thereby allowing for the achievement of broad spectrum antimicrobial efficacy, while reducing the number and / or concentration of antimicrobial preservatives otherwise required to achieve sufficient broad spectrum protection. The presently disclosed ether compounds can further provide beneficial multifunctional properties, such as one or more of antioxidant, surfactant, humectant and / or chelating properties.

[0011] SUMMARY OF INVENTION

[0012] Provided is a personal care, cosmetic or home care product composition comprising an antimicrobial preservative and an antimicrobial booster agent comprising at least one ether compound of formula (I) wherein R is hydroxyl, an unsubstituted or substituted Ci-Cs alkoxy or an unsubstituted or substituted C2-C8 alkenyloxy, or R taken together with the carbon atom to which it is bonded forms an aldehyde, an unsubstituted or substituted Ci-Cs alkyl ester or an unsubstituted or substituted C2-C8 alkenyl ester, and n is from 3 to 30.

[0013] In another aspect, a method of providing antimicrobial activity to a personal care, cosmetic or home care product composition (e.g., controlling or inhibiting the growth of microorganisms in or preserving a product composition) comprises adding to the composition an antimicrobial preservative and an antimicrobial booster agent comprising at least one ether compound of formula (I) as described herein.

[0014] In a further aspect, the present disclosure provides for the use of an antimicrobial booster agent comprising at least one ether compound of formula (I) as described herein for enhancing the antimicrobial efficacy of an antimicrobial preservative in a personal care, cosmetic or home care product composition.

[0015] In another aspect, provided is a method of enhancing the antimicrobial efficacy of an antimicrobial preservative in a personal care, cosmetic or home care product composition comprising combining or mixing the antimicrobial preservative with an antimicrobial booster agent comprising at least one ether compound of formula (I) as described herein. The antimicrobial efficacy is enhanced as compared to an equal amount of the antimicrobial preservative without the at least one ether compound of formula (I).

[0016] In a further aspect, provided is a method of reducing the minimum amount of an antimicrobial preservative needed for preservation activity in a personal care, cosmetic or home care product composition, the method comprising combining or mixing the antimicrobial preservative with an antimicrobial booster agent comprising at least one ether compound of formula (I) as described herein, wherein after said combining or mixing with the at least one ether compound, the minimum amount of the antimicrobial preservative needed for preservation activity in the product composition is less than if the antimicrobial preservative was used alone.

[0017] In another aspect, an antimicrobial composition comprises an antimicrobial preservative and an antimicrobial booster agent comprising at least one ether compound of formula (I) as described herein.

[0018] DETAILED DESCRIPTION

[0019] The ether compounds of the present disclosure are of the formula (I) wherein R is hydroxyl, an unsubstituted or substituted Ci-Cs (preferably Ci-Ce or C1-C4) alkoxy or an unsubstituted or substituted C2-C8 (preferably C2-C6 or C2-C4) alkenyloxy, or R taken together with the carbon atom to which it is bonded forms an aldehyde, an unsubstituted or substituted Ci-Cs (preferably Ci-Ce or C1-C4) alkyl ester or an unsubstituted or substituted C2-C8 (preferably C2-C6 or C2-C4) alkenyl ester, and n is from 3 to 30, or, more particularly, from 4 to 30. More preferably, n is from 3 to 20, or, more particularly, from 4 to 20.

[0020] As used herein, “alkoxy” refers to the group -O-alkyl, wherein alkyl has the specified number of carbon atoms.

[0021] As used herein, “alkenyloxy” refers to the group -O-alkenyl, wherein alkenyl has the specified number of carbon atoms and refers to unsaturated hydrocarbon having at least one double bond, e.g., vinyl, allyl, etc.

[0022] In some embodiments, R in the formula (I) taken together with the carbon atom to which it is bonded forms an aldehyde, an unsubstituted or substituted Ci-Cs (preferably Ci-Ce or C1-C4) alkyl ester or an unsubstituted or substituted C2-C8 (preferably C2-C6 or C2-C4) alkenyl ester, as shown in the following subformula (II): where R1is H, -O-alkyl or -O-alkenyl, wherein the alkyl or alkenyl has the specified number of carbon atoms as described above and may be unsubstituted or substituted, and n is as described herein.

[0023] The alkyl or alkenyl in connection with the alkoxy, alkenyloxy and ester groups may be straight- chained or branched. The alkoxy, alkenyloxy and ester groups may be unsubstituted or substituted. That is, the alkyl or alkenyl group therein may be unsubstituted or substituted. For example, at least one hydrogen atom of the alkyl or alkenyl group may be substituted by hydroxyl and / or the alkyl or alkenyl may be interrupted by at least one oxygen atom, at least one carbonyl or a combination thereof.

[0024] Particular examples of suitable alkoxy groups substituted by at least one hydroxyl include, but are not limited to,-O-CH2CH2OH, -O-CH2-C(CH2OH)2(CH2CH3), -O-CH2-C(CH2OH)3,

[0025] Preferably, R in formula (I) is hydroxyl. Where R in formula (I) is alkenyloxy, in many embodiments R is vinyloxy or allyloxy. Where R in formula (I) is taken together with the carbon atom to which it is bonded to form an alkenyl ester, in many embodiments the alkenyl ester is vinyl ester or allyl ester (i.e., R1in formula (II) is -O-alkenyl and the alkenyl is vinyl or allyl).

[0026] In many embodiments, the booster agent of the present disclosure comprises a mixture of the ether compounds of the present disclosure. The at least one ether compound may be a mixture of two or more ether compounds of the formula (I) (or the formula (II)) wherein at least 2, or in many embodiments at least 3 or at least 4, of the compounds differ from one another at least in the value for n. For example, in many embodiments, the mixture of ether compounds may be a mixture of three or more, or a mixture of four or more, ether compounds wherein at least 3, or at least 4, of the compounds differ from one another at least in the value for n.

[0027] Examples of ether compounds of the present disclosure, including mixtures thereof, include, without limitation, those identified in Table 1 below in the Examples section.

[0028] The ether compounds may be synthesized according to known methods or may be obtained as commercially available compounds.

[0029] In a further aspect of the present disclosure, the ether compounds as described herein have one or more properties chosen from antioxidant, surfactant, humectant and chelating properties, such as described or demonstrated herein. Preferably, the ether compound of the present disclosure or mixture thereof has at least an antioxidant property, at least a chelating property or a combination thereof. With respect to the antioxidant property, the ether compound or mixture thereof preferably shows a pM Trolox equivalents (TE) value (i.e., pmol Trolox / L sample) of at least 50 pM TE, more preferably at least 75 pM TE or at least 100 pM TE, in particular at least 150 pM TE, at least 200 pM TE or at least 250 pM TE, where the TE value is determined according to the assay procedure of the Activated ABTS Antioxidant Assay Kit (Cat# AOX-14) (instruction manual ZBM0123.00, April 2021). With respect to the chelating property, the ether compound or mixture thereof preferably shows a pM EDTA equivalents value (i.e., pmol EDTA / L sample) of at least 100 pM EDTA equivalents, more preferably at least 125 pM EDTA equivalents or at least 150 pM EDTA equivalents, in particular at least 200 pM EDTA equivalents, at least 250 pM EDTA equivalents or at least 300 pM EDTA equivalents, where the EDTA equivalents value is determined according to the assay procedure of the Cupric Ion Chelating Assay Kit (Cat# AOX-16) (instruction manual ZBM0125.00, July 2021).

[0030] As the antimicrobial preservative, traditional and / or soft preservatives may be used. The ether compounds of the present disclosure can be used to decrease the number and / or amount of such antimicrobial preservatives otherwise required to achieve desired preservation activity in personal care products, cosmetics products and home care products. Suitable antimicrobial preservatives for personal care products, cosmetic products, and home care products are known in the art. Examples of such traditional preservatives include isothiazolinones (e.g., 5 -chloro-2 -methyl -4-isothiazolin-3 -one (CMIT), 2-methyl-4-isothiazolin-3-one (MIT), and l,2-benzisothiazolin-3-one (BIT)), formaldehyde releasers (e.g., bronopol and l,3-bis(hydroxymethyl)-5,5-dimethylimidazolidine-2, 4-dione), and parabens (e.g., methylparaben, ethylparaben, propylparaben, and butylparaben). The antimicrobial preservative may be a soft preservative.

[0031] Preferably, the antimicrobial preservative comprises an isothiazolinone (e.g., CMIT, MIT, BIT, combinations thereof), an alkylhydroxamic acid and / or salt thereof (e.g., hexanohydroxamic acid, caprylhydroxamic acid, decanohydroxamic acid, laurohydroxamic acid, salts thereof, combinations thereof, preferably caprylhydroxamic acid and / or a salt thereof), an aromatic aldehyde (e.g., cinnamic aldehyde), an alcohol (e.g., an aromatic alcohol, such as benzyl alcohol, dichlorobenzyl alcohol, phenethyl alcohol, cinnamic alcohol, a phenolic compound, such as hydroxyacetophenone, combinations thereof), a diol (e.g., bronopol, glycols, such as 1,2-propanediol, 1,3 -butanediol, 1,2- pentanediol, 1,2 -hexanediol, 1,2-heptanediol, 1,2-octanediol (i.e., caprylyl glycol), combinations thereof), a glyceryl ether (e.g., ethylhexylglycerin, chlorphene sin), an aromatic ether (e.g., phenoxyethanol), a pyrithione (e.g., zinc pyrithione, sodium pyrithione), an organic acid (e.g., benzoic acid, propionic acid, salicylic acid, sorbic acid, formic acid, citric acid, hexa-2,4-dienoic acid, 4- hydroxybenzoic acid, combinations thereof), a salt and / or ester of an organic acid (e.g., esters and / or salts of the above organic acids, such as salts of sodium, potassium, calcium, magnesium or ammonium, including, e.g., sodium benzoate, potassium sorbate and the like, and esters of methyl, ethyl, propyl, isopropyl, butyl, isobutyl or phenyl, including butyl benzoate and the like), ethyl lauroyl arginate (LAE), or any combination of the foregoing.

[0032] For example, the antimicrobial preservative may comprise an alkylhydroxamic acid and / or salt thereof (preferably, hexanohydroxamic acid, caprylhydroxamic acid, decanohydroxamic acid, laurohydroxamic acid and / or salt thereof or combination thereof, particularly caprylhydroxamic acid and / or salt thereof), phenoxyethanol, benzyl alcohol, hydroxyacetophenone, dichlorobenzyl alcohol, phenethyl alcohol, cinnamic aldehyde, cinnamic alcohol, 1,2-propanediol, 1,3-butanediol, 1,2- pentanediol, 1,2 -hexanediol, 1,2-heptanediol, 1,2-octanediol (i.e., caprylyl glycol), bronopol, ethylhexylglycerin, chlorphenesin, CMIT, MIT, BIT, benzoic acid, propionic acid, salicylic acid, sorbic acid, formic acid, citric acid, hexa-2,4-dienoic acid, 4-hydroxybenzoic acid, a salt and / or ester of the foregoing acids, zinc pyrithione, sodium pyrithione or a combination thereof.

[0033] Preferably, the antimicrobial preservative comprises an isothiazolinone, an aromatic aldehyde, an aromatic alcohol, an aromatic ether, an organic acid, a salt or ester of an organic acid, a pyrithione, ethyl lauroyl arginate (LAE) or a combination thereof.

[0034] In particular, the antimicrobial preservative may comprise caprylhydroxamic acid, phenoxyethanol, benzyl alcohol, 2,4-dichlorobenzyl alcohol, phenethyl alcohol, ethyl lauroyl arginate (LAE), CMIT, MIT, BIT, benzoic acid, propionic acid, salicylic acid, sorbic acid, formic acid, citric acid, hexa-2,4- dienoic acid, 4-hydroxybenzoic acid, an ester or salt of said organic acids (e.g., sodium benzoate, potassium sorbate and the like), or a combination thereof. For example, the antimicrobial preservative may preferably comprise phenoxyethanol, benzyl alcohol, benzoic acid, a salt of benzoic acid (e.g., sodium benzoate), ethyl lauroyl arginate, CMIT, MIT, BIT or a combination thereof.

[0035] More than one antimicrobial preservative may be present or used in the compositions and methods of the present disclosure.

[0036] Optimized amounts of an antimicrobial preservative and the booster agent comprising the at least one ether compound of formula (I) (or formula (II)) may vary depending, for example, on the particular compound(s) and preservative selected, the end use application, the desired level of preservation, the final properties of the product, and the like. In general, the at least one ether compound is provided or is present in an amount effective to enhance the antimicrobial efficacy (e.g., enhance a desired preservative, antibacterial and / or antifungal effect) of an antimicrobial preservative in a product composition, such as a personal care, cosmetic or home care composition, (e.g., to meet or even exceed industry standards for antimicrobial efficacy) as compared to an equal amount of the antimicrobial preservative without the at least one ether compound. In addition, the amount of the at least one ether compound may also be influenced by the desired multifunctional benefits, such as one or more of antioxidant, surfactant, humectant and / or chelating properties, as described herein.

[0037] In general, the weight ratio of the at least one ether compound of formula (I) (or formula (II)) to an antimicrobial preservative may range from about 1:50 to about 50: 1, such as from about 1:20 to about 20: 1, from about 1: 15 to about 15: 1, from about 1: 10 to about 10: 1, or from about 1:5 to about 5: 1, although other ratios may be used. The present application provides for the use of the presently disclosed ether compounds and antimicrobial preservatives in product compositions, such as personal care products, cosmetic products and home care products. In general, the at least one ether compound and an antimicrobial preservative each may be provided to or present in the product composition in an amount ranging from about 0.001 wt%, from about 0.005 wt%, preferably from about 0.01 wt%, from about 0.05 wt%, more preferably from about 0.1 wt%, from about 0.3 wt%, or from about 0.5 wt% to about 5 wt%, preferably to about 3 wt%, to about 2 wt%, more preferably to about 1.5 wt%, or to about 1 wt%, based on the weight of the product composition, according to any combination of the foregoing lower and upper boundaries and any range therebetween. Other amounts may alternatively be used. Depending upon the antimicrobial preservative, it is envisioned that even lower amounts of the antimicrobial preservative may be used, such as from about 0.0001 wt% or higher or from about 0.0005 wt% or higher. In embodiments where such small amounts of the antimicrobial preservative is used, the amount by weight of the ether compound may be substantially proportionally higher than the amount by weight of the antimicrobial preservative, such as a ratio of the ether compound to the antimicrobial preservative as high as 100: 1, as high as 500: 1, as high as 1000: 1, as high as 5000: 1, or higher.

[0038] Typically, the combined amount of the at least one ether compound of the present disclosure and the antimicrobial preservative ranges from about 0.05 wt%, more preferably from about 0.1 wt%, from about 0.3 wt% or from about 0.5 wt% to about 10 wt%, preferably to about 5 wt%, more preferably to about 3 wt%, to about 2 wt%, to about 1.5 wt% or to about 1 wt%, based on the weight of the product composition, according to any combination of the foregoing lower and upper boundaries and any range therebetween. For example, the combined amount may be from about 0.05 to about 7 wt%, such as from about 0. 1 to about 5 wt%, from about 0.1 to about 4 wt%, from about 0. 1 to about 3 wt%, or from about 0.1, from about 0.3 or from about 0.5 to about 3, to about 2 or to about 1 wt%, based on the weight of the product composition.

[0039] Typically, the at least one ether compound and the antimicrobial preservative each is present in the product composition in an amount not exceeding about 2 wt%, preferably not exceeding about 1.5 wt% or not exceeding about 1 wt%, based on the weight of the product composition. Often each is present below 1 wt%. Preferably, the combined amount of the at least one ether compound and the antimicrobial preservative does not exceed about 3 wt% or does not exceed about 2 wt%, such as ranging from about 1.5 wt% or less (e.g., from about 0.1 wt% or from about 0.3 wt% to about 1.5 wt%), from about 1.2 wt% or less (e.g., from about 0. 1 wt% or from about 0.3 wt% to about 1.2 wt%) or from about 1 wt% or less (e.g., from about 0. 1 wt% or from about 0.3 wt% to about 1 wt%), based on the weight of the product composition.

[0040] The at least one ether compound of the present disclosure may be combined with an antimicrobial preservative or added to a product composition in any suitable manner. The at least one ether compound may be added to a product composition prior to the addition of the antimicrobial preservative, concurrently with the addition of the antimicrobial preservative or after the addition of the antimicrobial preservative.

[0041] The ether compounds of the present disclosure can be incorporated into any number and variety of different personal care, cosmetic and home care products, particularly aqueous-based formulations, whether water soluble or using water as a carrier, including emulsions (whether oil-in-water, water-in- oil, silicone -in-water, water-in-silicone, etc.). Examples include, without limitation, household products and cleaners, fabric detergents and softeners, dish detergents, cleansers, soaps, bubble baths, disinfectants, deodorizers, hygiene compositions, infant care products, antimicrobial soaps, hand sanitizers, deodorants, antiperspirants, dermatological compositions, skin conditioners, skin moisturizers, anti -wrinkle formulations, sunscreens, tanning lotions, hair products, shampoos, shower gels, conditioners, shaving creams, etc. Personal care products include, for example, products used in skincare, hair care, oral care, personal cleaning or hygiene, sun protection and other applications. Examples of personal care products include shampoos, conditioners, shower gels, liquid soaps, skin lotions, and liquids for any personal care wet wipe application. Examples of cosmetic products include face creams, makeup, makeup removers, mascaras and wet wipes. Examples of home care products include dish soaps, laundry detergents, cleaning wipes and cleaning formulations.

[0042] The product compositions may contain numerous and different ingredients depending on the end use application, that is, one or more additional ingredients suitable for use in a personal care, cosmetic or home care product composition. In one example, a personal care composition comprises an antimicrobial preservative and an antimicrobial booster agent comprising at least one ether compound of formula (I) (or formula (II)), as described herein, and one or more additional ingredients suitable for use in a personal care composition. In another example, a cosmetic composition comprises an antimicrobial preservative and an antimicrobial booster agent comprising at least one ether compound of formula (I) (or formula (II)), as described herein, and one or more additional ingredients suitable for use in a cosmetic composition. The personal care or cosmetic composition may be, for example, any formulation for skin care, hair care, cosmetics, personal cleaning, hygiene, sun protection and other similar applications. Examples of such products include, without limitation, skin toners, skin cleansers, night creams, skin creams, shaving creams, skin lotions, makeup, mascara, lipstick, blush, gloss, eye-liner, makeup removers, sunscreens, lip balms, fragrances, massage oils, shampoos, conditioners, hair styling gels, hair reparatives, hair tonics, hair fixatives, hair mousses, bath and shower gels, liquid soaps, moisturizing sprays, bath additives, ophthalmic preparations, foaming soaps and body washes, liquids for any personal care wet wipe application, etc.

[0043] Depending on the application, the personal care or cosmetic composition may contain numerous and different compatible ingredients, such as any of solvents, surfactants, emulsifiers, rheology modifiers, conditioners, emollients, skin care ingredients, moisturizers, thickeners, humectants, fillers, antioxidants, active ingredients, such as dermatologically active ingredients typically suited for topical application, fragrances and the like, and various mixtures thereof. .

[0044] As another example, a home care composition comprises an antimicrobial preservative and an antimicrobial booster agent comprising at least one ether compound of formula (I) (or formula (II)), as described herein, and one or more additional ingredients suitable for use in a home care composition. Examples include dish soaps, laundry detergents, cleaning wipes, cleaning formulations and other home care applications. Depending on the application, the home care composition may contain, for example, detergents, emulsifiers, surfactants, thickeners, gelling agents, bleaches, whiteners, deodorizers, enzymes, stabilizers, fragrances and the like, and various mixtures thereof.

[0045] Examples of the foregoing ingredients and other agents used in personal care, cosmetic and home care product compositions are known in the art.

[0046] The ether compounds of the present disclosure may be included in product compositions of a variety of different forms, for example, liquids, pastes, serums, hydrogels, creams, emulsions, lotions, gels, oils, wipes, ointments, semi-solid compositions, and aerosol sprays. For example, they can be used in hair care products, such as shampoos, hair conditioners, hair dyes, hair tonic, hair gel, hair dressings, hair grooming aids and other hair care preparations; shaving applications such as shaving cream, aftershave lotions, and other shaving applications; personal cleaners for the body and hands, such as liquid bath soaps and detergents; fragrance preparations, such as perfumes, after bath splashes, and other similar fragrant preparations, skin care products, such as moisturizers, creams, and lotions and other similar skin care products, make-up products, such as mascara, base foundations and the like; make-up removal products, sun care products, indoor tanning products and other similar personal care products; in formulations used to saturate wipes used for personal cleaning and hygiene, for example, baby wipes, wet toilet wipes, make-up removal wipes and exfoliating wipes and the like, or wet wipe formulations for home care.

[0047] Typically, the product composition has a pH ranging from about 3.0, from about 4.0, from about 5.0, from about 5.5, or from about 6.0 to about 11, such as from about 3.0 to about 10, from about 4.0 to about 8.5, or from about 5.0 to about 7.5. Unless otherwise specified, pH values or ranges refer to pH at room temperature (20-25 °C). The selected pH will vary depending, for example, on the particular end use application. For example, the personal care or cosmetic composition preferably has a pH ranging from about 3.0 or from about 4.0 to about 8.0, such as from about 4.0 or from about 5.0 to about 7.5 or to about 7.0. The home care composition preferably has a pH ranging from about 3.0 to about 11, such as from about 4.0 or from about 5.0 to about 10, or from about 5.0 or from about 6.0 to about 9.0, to about 8.0, to about 7.5 or to about 7.0.

[0048] In another aspect of the present disclosure, a method of providing antimicrobial activity to a personal care, cosmetic or home care product composition comprises adding to the composition an antimicrobial preservative and an antimicrobial booster agent comprising at least one ether compound of formula (I) (or formula (II)).

[0049] The present disclosure is not limited to any particular technique for preparing a product composition, and the antimicrobial preservative and the booster agent comprising the at least one ether compound may be added to a product composition in any suitable manner. For example, the antimicrobial preservative and the booster agent comprising the at least one ether compound of formula (I) (or formula (II)) can be applied to a product formulation as a mixture or applied individually to the formulation at the same time or in any order.

[0050] In a further aspect, the present disclosure provides for the use of an antimicrobial booster agent comprising at least one ether compound of formula (I) (or formula (II)) as described herein for enhancing the antimicrobial efficacy of an antimicrobial preservative in a personal care, cosmetic or home care product composition.

[0051] In another aspect, provided is a method of enhancing the antimicrobial efficacy of an antimicrobial preservative in a personal care, cosmetic or home care product composition comprising combining or mixing the antimicrobial preservative with an antimicrobial booster agent comprising at least one ether compound of formula (I) (or formula (II)) as described herein. The antimicrobial efficacy is enhanced as compared to an equal amount of the antimicrobial preservative without the ether compound.

[0052] In a further aspect, provided is a method of reducing the minimum amount of an antimicrobial preservative needed for preservation activity in a personal care, cosmetic or home care product composition, the method comprising combining or mixing the antimicrobial preservative with an antimicrobial booster agent comprising at least one ether compound of formula (I) (or formula (II)) as described herein, wherein after said combining or mixing with the at least one ether compound, the minimum amount of the antimicrobial preservative needed for preservation activity in the product composition is less than if the antimicrobial preservative was used alone.

[0053] It shall be understood that the descriptions herein with respect to the at least one ether compound of the present disclosure, the antimicrobial preservative, exemplary ratios and amounts, product compositions and ingredients, etc. also apply to the methods of the present disclosure.

[0054] Various different microorganisms may be controlled in accordance with the present disclosure. For example, a combination of an antimicrobial preservative and the at least one ether compound of the present disclosure preferably controls gram positive bacteria, gram negative bacteria, and fungi, among other microorganisms. Non-limiting examples include Staphylococcus aureus, Staphylococcus epidermidis. Pseudomonas aeruginosa, Escherichia coli, Enterohacter gergoviae, Klebsiella pneumoniae, Burholderia cepacia, Pseudomonas putida, Candida albicans, Aspergillus brasiliensis, and mixtures thereof. As known in the art, an antimicrobial effect may be demonstrated by various suitable antimicrobial effectiveness tests. Preferably, when added to a product composition, the antimicrobial preservative and the at least one ether compound of the present disclosure provide an antimicrobial effect according to the challenge test procedures in the below Examples achieving a passing growth rating according to the criteria associated with Table 4 and the associated description herein. In a further aspect of the present disclosure, an antimicrobial composition comprises an antimicrobial preservative and an antimicrobial booster compound comprising at least one ether compound of formula (I) (or formula (II)) as described herein, preferably wherein the antimicrobial preservative and the at least one ether compound collectively constitute from 50 to 100 wt% of the active ingredients in the antimicrobial composition, further preferably wherein the antimicrobial preservative comprises an isothiazolinone (e.g., CMIT, MIT, BIT, combinations thereof), an alkylhydroxamic acid and / or salt thereof (e.g., hexanohydroxamic acid, caprylhydroxamic acid, decanohydroxamic acid, laurohydroxamic acid, salts thereof, combinations thereof, preferably caprylhydroxamic acid and / or a salt thereof), an aromatic aldehyde (e.g., cinnamic aldehyde), an alcohol (e.g., an aromatic alcohol, such as benzyl alcohol, dichlorobenzyl alcohol, phenethyl alcohol, cinnamic alcohol, a phenolic compound, such as hydroxy acetophenone, combinations thereof), a diol (e.g., bronopol, glycols, such as 1,2-propanediol, 1,3-butanediol, 1,2-pentanediol, 1,2-hexanediol, 1,2-heptanediol, 1,2-octanediol (i.e., caprylyl glycol), combinations thereof), a glyceryl ether (e.g., ethylhexylglycerin, chlorphene sin), an aromatic ether (e.g., phenoxyethanol), a pyrithione (e.g., zinc pyrithione, sodium pyrithione), an organic acid (e.g., benzoic acid, propionic acid, salicylic acid, sorbic acid, formic acid, citric acid, hexa-2,4-dienoic acid, 4 -hydroxybenzoic acid, combinations thereof), a salt and / or ester of an organic acid (e.g., esters and / or salts of the above organic acids, such as salts of sodium, potassium, calcium, magnesium or ammonium, including, e.g., sodium benzoate, potassium sorbate and the like, and esters of methyl, ethyl, propyl, isopropyl, butyl, isobutyl or phenyl, including butyl benzoate and the like), ethyl lauroyl arginate (LAE), or a combination thereof.

[0055] For example, the antimicrobial preservative may comprise an alkylhydroxamic acid and / or salt thereof (preferably, hexanohydroxamic acid, caprylhydroxamic acid, decanohydroxamic acid, laurohydroxamic acid and / or salt thereof or combination thereof, particularly caprylhydroxamic acid and / or salt thereof), phenoxyethanol, benzyl alcohol, hydroxyacetophenone, dichlorobenzyl alcohol, phenethyl alcohol, cinnamic aldehyde, cinnamic alcohol, 1,2-propanediol, 1,3-butanediol, 1,2- pentanediol, 1,2-hexanediol, 1,2-heptanediol, 1,2-octanediol (i.e., caprylyl glycol), bronopol, ethylhexylglycerin, chlorphenesin, CMIT, MIT, BIT, benzoic acid, propionic acid, salicylic acid, sorbic acid, formic acid, citric acid, hexa-2,4-dienoic acid, 4-hydroxybenzoic acid, a salt and / or ester of the foregoing acids, zinc pyrithione, sodium pyrithione or a combination thereof.

[0056] Preferably, the antimicrobial preservative comprises an isothiazolinone, an aromatic aldehyde, an aromatic alcohol, an aromatic ether, an organic acid, a salt or ester of an organic acid, a pyrithione, ethyl lauroyl arginate (LAE) or a combination thereof.

[0057] In particular, the antimicrobial preservative may comprise caprylhydroxamic acid, phenoxyethanol, benzyl alcohol, 2,4-dichlorobenzyl alcohol, phenethyl alcohol, ethyl lauroyl arginate (LAE), CMIT, MIT, BIT, benzoic acid, propionic acid, salicylic acid, sorbic acid, formic acid, citric acid, hexa-2,4- dienoic acid, 4-hydroxybenzoic acid, an ester or salt of said organic acids (e.g., sodium benzoate, potassium sorbate and the like), or a combination thereof. For example, the antimicrobial preservative may preferably comprise phenoxyethanol, benzyl alcohol, benzoic acid, a salt of benzoic acid (e.g., sodium benzoate), ethyl lauroyl arginate, CMIT, MIT, BIT or a combination thereof.

[0058] Typically, the antimicrobial composition comprises an antimicrobial preservative and an antimicrobial booster agent comprising at least one ether compound of formula (I) (or formula (II)) such that the antimicrobial preservative and the at least one ether compound are present in a combined amount that is a majority (>50 wt%) of the active ingredients in the antimicrobial composition, such as at least 60 wt% or at least 70 wt%, preferably at least 80 wt%, more preferably at least 85 wt%, at least 90 wt%, at least 95 wt%, at least 96 wt%, at least 97 wt%, at least 98 wt% or at least 99 wt%, based on the total weight of active ingredients in the antimicrobial composition. The antimicrobial composition often contains from about 60 to 100 wt%, preferably from about 65 to 100 wt%, from about 70 to 100 wt%, from about 75 to 100 wt%, from about 80 to 100 wt%, from about 85 to 100 wt%, from about 90 to 100 wt%, or from about 95 or from about 97 to 100 wt%, of an antimicrobial preservative and the at least one ether compound combined, based on the total weight of active ingredients in the antimicrobial composition. In many embodiments, the antimicrobial composition comprises active ingredients consisting essentially of, or in further embodiments consisting of, an antimicrobial preservative and the at least one ether compound.

[0059] Preferably, the antimicrobial composition comprises an antimicrobial preservative and at least one ether compound of the present disclosure in a combined amount of 50 to 100 wt% of the total weight of the antimicrobial composition, typically a majority (>50 wt%) of the antimicrobial composition, such as at least 60 wt% or at least 70 wt%, preferably at least 80 wt%, more preferably at least 85 wt%, at least 90 wt%, at least 95 wt%, at least 96 wt%, at least 97 wt%, at least 98 wt% or at least 99 wt%, based on the total weight of the antimicrobial composition. The antimicrobial composition often contains from about 60 to 100 wt%, preferably from about 70 to 100 wt%, from about 75 to 100 wt%, from about 80 to 100 wt%, from about 85 to 100 wt%, from about 90 to 100 wt%, or from about 95 or about 97 to 100 wt%, of an antimicrobial preservative and the at least one ether compound combined, based on the total weight of the antimicrobial composition. In many embodiments, the antimicrobial composition consists essentially of, or in further embodiments consists of, an antimicrobial preservative and the at least one ether compound.

[0060] The antimicrobial composition may, but need not, comprise one or more added solvents or carriers. If present, the solvent or carrier typically constitutes from about 10 wt%, from about 20 wt% or from about 30 wt% to about 90 wt%, to about 85 wt%, to about 80 wt%, to about 70 wt%, to about 60 wt% or to about 50 wt%, based on the total weight of the antimicrobial composition. Solvents or carriers may be chosen according to their compatibility or suitability for a desired end application or end product formulation, such as in a personal care, cosmetic or home care composition, (e.g., a cosmetically acceptable solvent or carrier). Suitable solvents and carriers include, but are not limited to, water, water-miscible solvents, C1-C4 alcohols, C1-C4 diols (e.g., glycols), glycerin and the like.

[0061] The antimicrobial composition may, but need not, contain one or more excipients, typically in minor quantities. Excipients may similarly be chosen according to their compatibility or suitability for a desired end application or end product formulation, such as in a personal care, cosmetic or home care composition, (e.g., a cosmetically acceptable excipient). Examples of excipients include, but are not limited to, a dispersant, solubilizer, buffer, and / or stabilizer. The antimicrobial composition may comprise, for example, from 0 to about 10 wt% of one or more excipients, such as from about 0.001 wt%, from about 0.01 wt%, from about 0.05 wt% or from about 0. 1 wt% to about 5 wt%, to about 3 wt%, or to about 1 wt%, based on the total weight of the antimicrobial composition. For example, the amount of excipients may range from 0 to about 5 wt%, from 0 to about 3 wt% from about 0.01 to about 5 wt%, from about 0.1 to about 5 wt%, from about 0.01 to about 3 wt%, from about 0.1 to about 3 wt%, from about 0.01 to about 1 wt%, or from about 0. 1 to about 1 wt%.

[0062] In general, the antimicrobial composition may comprise a combined amount of an antimicrobial preservative and at least one ether compound of the present disclosure of from about 10 to 100 wt%, such as from about 15 wt% or from about 20 wt%, from about 30 wt%, from about 40 wt%, from about 50 wt% or from about 60 wt% to 100 wt%, to about 99 wt%, to about 97 wt%, to about 95 wt%, to about 90 wt%, to about 80 wt%, or to about 70 wt%, based on the total weight of the antimicrobial composition; optionally one or more solvents or carriers in an amount from 0 to about 90 wt%, such as from about 10 wt%, from about 20 wt% or from about 30 wt% to about 90 wt%, to about 85 wt%, to about 80 wt%, to about 70 wt%, to about 60 wt%, to about 50 wt%, or to about 40 wt%, based on the total weight of the antimicrobial composition; and optionally one or more excipients in an amount from about 0 to about 10 wt%, such as from about 0.001 wt%, from about 0.01 wt%, from about 0.05 wt% or from about 0. 1 wt% to about 5 wt%, to about 3 wt%, or to about 1 wt%, based on the total weight of the antimicrobial composition. For example, the combined amount of an antimicrobial preservative and the at least one ether compound may be from about 10 wt% to about 90 wt%, from about 20 wt% to about 80 wt%, or from about 30 wt% to about 70 wt%, and the amount of solvent or carrier may be from about 10 wt% to about 90 wt%, from about 20 wt% to about 80 wt%, or from about 30 wt% to about 70 wt%, optionally further comprising one or more excipients.

[0063] In many embodiments, the antimicrobial composition consists essentially of, or in further embodiments consists of, an antimicrobial preservative, at least one ether compound of the present disclosure, optionally one or more solvents or carriers and optionally one or more excipients.

[0064] The antimicrobial composition can be added to a product composition in an amount effective to achieve a desired level of antimicrobial efficacy in or preservation of the product composition. It shall be understood that the descriptions herein with respect to the at least one ether compound of the present disclosure formula (I), the antimicrobial preservative, exemplary ratios and amounts, product compositions and ingredients, etc. also apply to the antimicrobial composition of the present disclosure and / or its addition to product compositions, particularly personal care, cosmetic or home care product compositions.

[0065] The present disclosure further includes, without limitation, the following exemplary embodiments.

[0066] Embodiment 1 : An antimicrobial composition comprising an antimicrobial preservative and an antimicrobial booster agent comprising at least one ether compound of formula (I) wherein R is hydroxyl, an unsubstituted or substituted Ci-Cs (preferably Ci-Ce or C1-C4) alkoxy or an unsubstituted or substituted C2-C8 (preferably C2-C6 or C2-C4) alkenyloxy, or R taken together with the carbon atom to which it is bonded forms an aldehyde, an unsubstituted or substituted Ci-Cs (preferably Ci-Ce or C1-C4) alkyl ester or an unsubstituted or substituted C2-C8 (preferably C2-C6 or C2-C4) alkenyl ester, and n is from 3 to 30, or, more particularly, n is from 4 to 30, preferably wherein n is from 3 to 20, or, more particularly, n is from 4 to 20.

[0067] Embodiment 2: A product composition comprising an antimicrobial preservative and an antimicrobial booster agent comprising at least one ether compound of formula (I) as described in Embodiment 1, wherein the product composition is chosen from personal care products, cosmetic products, and home care products.

[0068] Embodiment 3 : A method of providing antimicrobial activity to a product composition, comprising adding to the product composition an antimicrobial preservative and an antimicrobial booster agent comprising at least one ether compound of formula (I) as described in Embodiment 1, and the product composition is chosen from personal care products, cosmetic products, and home care products.

[0069] Embodiment 4: A method of enhancing the antimicrobial efficacy of an antimicrobial preservative in a product composition, comprising adding to the product composition an antimicrobial booster agent comprising at least one ether compound of formula (I) as described in Embodiment 1, wherein the product composition is chosen from personal care products, cosmetic products, and home care products.

[0070] Embodiment 5 : A method of enhancing the antimicrobial efficacy of an antimicrobial preservative in a product composition, comprising combining or mixing the antimicrobial preservative with an antimicrobial booster agent comprising at least one ether compound of formula (I) as described in Embodiment 1, wherein the product composition is chosen from personal care products, cosmetic products, and home care products.

[0071] Embodiment 6: Use of an antimicrobial booster agent comprising at least one ether compound of formula (I) as described in Embodiment 1 for enhancing the antimicrobial efficacy of an antimicrobial preservative in a product composition, wherein the product composition is chosen from personal care products, cosmetic products, and home care products.

[0072] Embodiment 7 : The antimicrobial composition, product composition, method or use according to any preceding Embodiment, wherein R in formula (I) is hydroxyl, an unsubstituted or substituted Ci-Cs (preferably Ci-Ce or C1-C4) alkoxy or an unsubstituted or substituted C2-C8 (preferably C2-C6 or C2- C4) alkenyloxy.

[0073] Embodiment 8: The antimicrobial composition, product composition, method or use according to any preceding Embodiment, wherein R in formula (I) is hydroxyl.

[0074] Embodiment 9: The antimicrobial composition, product composition, method or use according to any one of Embodiments 1-6, wherein R taken together with the carbon atom to which it is bonded forms an aldehyde, an unsubstituted or substituted Ci-Cs (preferably Ci-Ce or C1-C4) alkyl ester or an unsubstituted or substituted C2-C8 (preferably C2-C6 or C2-C4) alkenyl ester.

[0075] Embodiment 10: The antimicrobial composition, product composition, method or use according to any preceding Embodiment, wherein the antimicrobial booster agent comprises a mixture of ether compounds of formula (I).

[0076] Embodiment 11 : The antimicrobial composition, product composition, method or use according to Embodiment 10, wherein the mixture of ether compounds of formula (I) contains at least two compounds differing from one another at least in the value for n.

[0077] Embodiment 12: The antimicrobial composition, product composition, method or use according to Embodiment 11, wherein the mixture of ether compounds of formula (I) contains at least three compounds differing from one another at least in the value for n.

[0078] Embodiment 13: The antimicrobial composition, product composition, method or use according to Embodiment 12, wherein the mixture of ether compounds of formula (I) contains at least four compounds differing from one another at least in the value for n.

[0079] Embodiment 14: The antimicrobial composition, product composition, method or use according to any preceding Embodiment, wherein the ratio of the antimicrobial preservative to the at least one ether compound of formula (I) ranges from about 1:50 to about 50: 1, preferably from about 1:20 to about 20: 1, from about 1 : 15 to about 15: 1, from about 1 : 10 to about 10 : 1 , or from about 1 : 5 to about 5: 1. Embodiment 15: The antimicrobial composition of any one of Embodiments 1 and 7-14, wherein the antimicrobial composition contains greater than or about equal to 50 wt% of the antimicrobial preservative and the at least one ether compound of formula (I) combined, based on the total weight of active ingredients in the antimicrobial composition, preferably from about 60 to 100 wt%, from about 70 to 100 wt%, from about 75 to 100 wt%, from about 80 to 100 wt%, from about 85 to 100 wt%, from about 90 to 100 wt%, or from about 95 or from about 97 to 100 wt%, based on the total weight of active ingredients in the antimicrobial composition.

[0080] Embodiment 16: The antimicrobial composition of any one of Embodiments 1 and 7-15, wherein the antimicrobial composition comprises active ingredients consisting essentially of, or in further embodiments consisting of, the antimicrobial preservative and the at least one ether compound of formula (I).

[0081] Embodiment 17: The antimicrobial composition of any one of Embodiments 1 and 7-16, wherein the antimicrobial composition contains greater than or about equal to 50 wt% of the antimicrobial preservative and the at least one ether compound of formula (I) combined, based on the total weight of the antimicrobial composition, preferably from about 60 to 100 wt%, from about 70 to 100 wt%, from about 75 to 100 wt%, from about 80 to 100 wt%, from about 85 to 100 wt%, from about 90 to 100 wt%, or from about 95 or from about 97 to 100 wt%, based on the total weight of the composition.

[0082] Embodiment 18: The antimicrobial composition of any one of Embodiments 1 and 7-17, wherein the antimicrobial composition consists essentially of, or in further embodiments consists of, the antimicrobial preservative, the at least one ether compound of formula (I), optionally one or more solvents or carriers and optionally one or more excipients.

[0083] Embodiment 19: The antimicrobial composition, product composition, method or use according to any preceding Embodiment, wherein the antimicrobial preservative comprises an isothiazolinone (e.g., CMIT, MIT, BIT, combinations thereof), an alkylhydroxamic acid and / or salt thereof (e.g., hexanohydroxamic acid, caprylhydroxamic acid, decanohydroxamic acid, laurohydroxamic acid, salts thereof, combinations thereof, preferably caprylhydroxamic acid and / or a salt thereof), an aromatic aldehyde (e.g., cinnamic aldehyde), an alcohol (e.g., an aromatic alcohol, such as benzyl alcohol, dichlorobenzyl alcohol, phenethyl alcohol, cinnamic alcohol, a phenolic compound, such as hydroxyacetophenone, combinations thereof), a diol (e.g., bronopol, glycols, such as 1,2-propanediol, 1,3-butanediol, 1,2-pentanediol, 1,2-hexanediol, 1,2-heptanediol, 1,2-octanediol (i.e., caprylyl glycol), combinations thereof), a glyceryl ether (e.g., ethylhexylglycerin, chlorphenesin), an aromatic ether (e.g., phenoxyethanol), a pyrithione (e.g., zinc pyrithione, sodium pyrithione), an organic acid (e.g., benzoic acid, propionic acid, salicylic acid, sorbic acid, formic acid, citric acid, hexa-2,4-dienoic acid, 4-hydroxybenzoic acid, combinations thereof), a salt and / or ester of an organic acid (e.g., esters and / or salts of the above organic acids, such as salts of sodium, potassium, calcium, magnesium or ammonium, including, e.g., sodium benzoate, potassium sorbate and the like, and esters of methyl, ethyl, propyl, isopropyl, butyl, isobutyl or phenyl, including butyl benzoate and the like), ethyl lauroyl arginate (LAE), or a combination thereof.

[0084] Embodiment 20: The antimicrobial composition, product composition, method or use according to any one of Embodiments 1-18, wherein the antimicrobial preservative comprises an isothiazolinone (e.g., CMIT, MIT, BIT, combinations thereof), an aromatic aldehyde (e.g., cinnamic aldehyde), an aromatic alcohol (e.g., benzyl alcohol, dichlorobenzyl alcohol, phenethyl alcohol, cinnamic alcohol, a phenolic compound, such as hydroxyacetophenone, combinations thereof), an aromatic ether (e.g., phenoxyethanol), an organic acid (e.g., benzoic acid, propionic acid, salicylic acid, sorbic acid, formic acid, citric acid, hexa-2,4-dienoic acid, 4 -hydroxybenzoic acid, combinations thereof), a salt or ester of an organic acid (e.g., esters and / or salts of the above organic acids, such as salts of sodium, potassium, calcium, magnesium or ammonium, including, e.g., sodium benzoate, potassium sorbate and the like, and esters of methyl, ethyl, propyl, isopropyl, butyl, isobutyl or phenyl, including butyl benzoate and the like), a pyrithione (e.g., zinc pyrithione, sodium pyrithione), ethyl lauroyl arginate (LAE) or a combination thereof.

[0085] Embodiment 21 : The antimicrobial composition, product composition, method or use according to any one of Embodiments 1-18, wherein the antimicrobial preservative comprises an alkylhydroxamic acid and / or salt thereof (preferably, hexanohydroxamic acid, caprylhydroxamic acid, decanohydroxamic acid, laurohydroxamic acid and / or salt thereof or combination thereof, particularly caprylhydroxamic acid and / or salt thereof), phenoxyethanol, benzyl alcohol, hydroxyacetophenone, dichlorobenzyl alcohol, phenethyl alcohol, cinnamic aldehyde, cinnamic alcohol, 1,2-propanediol, 1,3-butanediol, 1,2-pentanediol, 1,2-hexanediol, 1,2-heptanediol, 1,2-octanediol (i.e., caprylyl glycol), bronopol, ethylhexylglycerin, chlorphene sin, CMIT, MIT, BIT, benzoic acid, propionic acid, salicylic acid, sorbic acid, formic acid, citric acid, hexa-2,4-dienoic acid, 4-hydroxybenzoic acid, a salt and / or ester of the foregoing acids, zinc pyrithione, sodium pyrithione or a combination thereof.

[0086] Embodiment 22: The antimicrobial composition, product composition, method or use according to any one of Embodiments 1-18, wherein the antimicrobial preservative comprises caprylhydroxamic acid, phenoxyethanol, benzyl alcohol, 2,4-dichlorobenzyl alcohol, phenethyl alcohol, ethyl lauroyl arginate (LAE), CMIT, MIT, BIT, benzoic acid, propionic acid, salicylic acid, sorbic acid, formic acid, citric acid, hexa-2,4-dienoic acid, 4-hydroxybenzoic acid, an ester or salt of said organic acids (e.g., sodium benzoate, potassium sorbate and the like), or a combination thereof; or the antimicrobial preservative comprises phenoxyethanol, benzyl alcohol, benzoic acid, a salt of benzoic acid (e.g., sodium benzoate), ethyl lauroyl arginate, CMIT, MIT, BIT or a combination thereof.

[0087] Embodiment 23: The product composition, method or use according to any one of Embodiments 2-14 and 19-22, wherein the at least one ether compound of formula (I) is present in the product composition in an amount ranging from about 0.05 wt%, preferably from about 0.1 wt%, from about 0.3 wt%, or from about 0.5 wt% to about 10 wt%, preferably to about 5 wt%, more preferably to about 3 wt%, to about 2 wt%, in particular to about 1.5 wt%, or to about 1 wt%, based on the total weight of the product composition.

[0088] Embodiment 24: The product composition, method or use according to any one of Embodiments 2-14 and 19-23, wherein the at least one ether compound of formula (I) and the antimicrobial preservative are each present in the product composition in an amount ranging from about 0.05 wt%, preferably from about 0.1 wt%, from about 0.3 wt%, or from about 0.5 wt% to about 5 wt%, preferably to about 3 wt%, to about 2 wt%, more preferably to about 1.5 wt%, or to about 1 wt%, based on the total weight of the product composition.

[0089] Embodiment 25: The product composition, method or use according to any one of Embodiments 2-14 and 19-24, wherein the at least one ether compound of formula (I) and the antimicrobial preservative are present in the product composition in a combined amount of from about 0. 1 wt%, from about 0.3 wt% or from about 0.5 wt% to about 10 wt%, preferably to about 5 wt%, more preferably to about 3 wt%, to about 2 wt%, to about 1.5 wt% or to about 1 wt%, based on the weight of the product composition.

[0090] Embodiment 26: The product composition, method or use according to any one of Embodiments 2-14 and 19-25, wherein the at least one ether compound of formula (I) and the antimicrobial preservative each is present in the product composition in an amount not exceeding 2 wt%, preferably not exceeding 1.5 wt% or not exceeding 1 wt%, based on the weight of the product composition.

[0091] Embodiment 27: The product composition, method or use according to any one of Embodiments 2-14 and 19-26, wherein the combined amount of the at least one ether compound of formula (I) and the antimicrobial preservative does not exceed 3 wt%, preferably does not exceed 2 wt%, such as from about 1.5 wt% or less (e.g., from about 0.1 wt% or from about 0.3 wt% to about 1.5 wt%), from about 1.2 wt% or less (e.g., from about 0. 1 wt% or from about 0.3 wt% to about 1.2 wt%) or from about 1 wt% or less (e.g., from about 0. 1 wt% or from about 0.3 wt% to about 1 wt%), based on the weight of the product composition.

[0092] Embodiment 28: The antimicrobial composition, product composition, method or use according to any preceding Embodiment, wherein the at least one ether compound of formula (I) has one or more properties chosen from antioxidant, surfactant, humectant and chelating properties, preferably wherein the at least one ether compound of formula (I) has at least an antioxidant property, at least a chelating property or at least a combination thereof.

[0093] Embodiment 29: The antimicrobial composition, product composition, method or use according to Embodiment 28, wherein the antioxidant property is a pM Trolox equivalents (TE) value (i.e., pmol Trolox / L sample) of at least 50 pM TE, more preferably at least 75 pM TE or at least 100 pM TE, in particular at least 150 pM TE, at least 200 pM TE or at least 250 pM TE, where the Trolox equivalents value is determined according to the assay procedure of the Activated ABTS Antioxidant Assay Kit (Cat# AOX-14) (instruction manual ZBM0123.00, April 2021).

[0094] Embodiment 30: The antimicrobial composition, product composition, method or use according to claim 28 or 29, wherein the chelating property is a pM EDTA equivalents value (i.e., pmol EDTA / L sample) of at least 100 pM EDTA equivalents, more preferably at least 125 pM EDTA equivalents or at least 150 pM EDTA equivalents, in particular at least 200 pM EDTA equivalents, at least 250 pM EDTA equivalents or at least 300 pM EDTA equivalents, where the EDTA equivalents value is determined according to the assay procedure of the Cupric Ion Chelating Assay Kit (Cat# AOX-16) (instruction manual ZBM0125.00, July 2021).

[0095] Embodiment 31 : The product composition, method or use according to any one of Embodiments 2-14 and 19-30, wherein the product composition is formulated as a liquid, paste, serum, hydrogel, cream, emulsion, lotion, gel, oil, wipe, ointment, semi-solid composition, or aerosol spray.

[0096] Embodiment 32: The product composition, method or use according to any one of Embodiments 2-14 and 19-31, wherein the product composition is a personal care or cosmetic product chosen from shampoos, conditioners, shower gels, liquid soaps, skin lotions, liquids for a wet wipe, face creams, hair treatments, makeup, and makeup removers.

[0097] Unless otherwise specified, the following terms are defined as follows:

[0098] As used herein, the articles “a”, “an”, and “the” preceding an element or component of the invention are intended to be nonrestrictive regarding the number of instances (i.e., occurrences) of the element or component. Therefore “a”, “an”, and “the” should be read to include one or at least one, and the singular word form of the element or component also includes the plural unless the number is obviously meant to be singular.

[0099] As used herein, the term “comprising” means the presence of the stated features, integers, steps, or components as referred to in the claims, but does not preclude the presence or addition of one or more other features, integers, steps, components or groups thereof. The term “comprising” is intended to include embodiments encompassed by the terms “consisting essentially of’ and “consisting of,” unless the context dictates otherwise. As used herein, the term “about” modifying the quantity of an ingredient or reactant employed refers to variation in the numerical quantity that can occur, for example, through typical measuring and liquid handling procedures used for making concentrates or use solutions in the real world; through inadvertent error in these procedures; through differences in the manufacture, source, or purity of the ingredients employed to make the compositions or carry out the methods; and the like.

[0100] Where present, all ranges are inclusive and combinable. For example, when a range of “1 to 5” is recited, the recited range should be construed as including ranges “1 to 4”, “1 to 3”, “1-2”, “1-2 & 4- 5”, “1-3 & 5”, and the like.

[0101] When a parameter is given either as a range, preferred range, or a list of upper preferable values and lower preferable values, this is to be understood as specifically disclosing all ranges formed from any pair of any upper range limit or preferred value and any lower range limit or preferred value, regardless of whether ranges are separately disclosed. Where a range of numerical values is recited herein, unless otherwise stated, the range is intended to include the endpoints thereof, and all integers and fractions within the range. The scope of the invention is not intended to be limited to the specific values and examples as recited in the specification.

[0102] EXAMPLES

[0103] The following examples demonstrate that the ether compounds of formula (I) of the present disclosure, when incorporated into various product formulations, enhanced the preservation efficacy of antimicrobial preservatives against a full spectrum of different bacteria and fungi, thereby enabling reduction in required preservative levels for protecting such products against microbial growth. The ether compounds of the present disclosure further showed significant antioxidant properties based on determined Trolox equivalent values and significant chelating properties based on determined EDTA equivalent values. Samples 1-5 shown in Table 1 are compounds representative of the presently disclosed ether compounds and used in the following experimental examples.

[0104] Table 1.

[0105] Example 1.

[0106] The preservative activity in representative rinse-off and leave-on product compositions was evaluated using a modification of the Personal Care Products Council (PCPC - formerly the Cosmetic, Toiletry and Fragrance Association) protocol (Machtiger, et al. 2001. Determination of the Efficacy of Preservation of Non-Eye Area Water Miscible Cosmetic and Toiletry Formulations: Collaborative Study. J of AO AC International. 84: 1, 101-109)

[0107] This evaluation was conducted using a four week, two-cycle microbial preservative efficacy test (i.e., challenge test) at 25°C to determine the preservative efficacy of each treatment. The presently disclosed ether compounds were tested alone and in combination certain antimicrobial preservatives. The compounds were dosed and mixed thoroughly at room temperature into a lotion composition (leave-on, Table 2). The lotion composition of Table 2 was prepared by heating the aqueous (A) and oil (B) phases separately to 75-80 °C. The oil phase was poured into the aqueous phase and mixed by a homogenizer at approximately 45 °C. The formed oil-in-water emulsion was cooled to room temperature. Triethanolamine was used to adjust the final pH to 6.3.

[0108] Table 2. Representative Lotion Formulation with Carbomer

[0109] After dosing, the samples were divided into two separate aliquots of 5 grams each. One aliquot was inoculated with 50 pl of a diluted bacterial pool, the second aliquot was inoculated with 50 pl of a diluted fungal pool as described below. Unpreserved product samples were included in the test as a growth control.

[0110] A mixed bacterial inoculum was prepared using 24-hour cultures of the test bacteria (Table 3) grown in trypticase soy broth (TSB). Equal volumes of the bacterial test strains were combined and diluted one to ten in phosphate buffer to obtain an inoculum of approximately 5 x 107to 5 x 108colony forming units per ml (cfu / ml). The test samples were inoculated with 1% of the mixed bacterial inoculum. A mixed fungal inoculum was prepared using cell suspensions of the yeast Candida albicans ATCC # 10231 and the mold Aspergillus brasiliensis ATCC #16404 in phosphate buffer. Equal volumes of the fungal test strains were combined and diluted one to ten with phosphate buffer to obtain an inoculum of approximately 5 x 106to 5 x 107cfu / ml. The test samples were inoculated with 1% of the mixed fungal inoculum.

[0111] Table 3. Mixed Bacterial Inoculum

[0112] The samples were subjected to microbial challenge at time zero and inoculated a second time after seven days. The number of microorganisms added to each sample was determined by a standard Most Probable Number (MPN) determination in Trypticase Soy Broth (TSB) for bacteria and Potato Dextrose Broth (PDB) for fungi. Samples were incubated at 25 °C for the test duration of four weeks. Samples were monitored for bacterial and fungal contamination after 2, 7, 14, 21, and 28 days. Samples challenged with bacteria were streak -plated onto Trypticase Soy Agar (TSA) and incubated at 30°C for 24 hours. Samples challenged with fungi were streak-plated onto Potato Dextrose Agar (PDA) and incubated at 25 °C for 7 days. After incubation, plates were given a Growth Rating to determine the colony forming units per gram (CFU / g) present in each test sample at the testing time point. Table 4 represents the growth score. A rating of excellent, good, and adequate were all considered to be a pass for the challenge test. As is used by various challenge test methods, the passing criteria was more stringent for bacteria than for fungi. A rating of 2, 3, or 4 at 21 and / or 28 days was considered a fail for bacteria. For fungi, a rating of 2 at 21 and / or 28 days was considered a pass.

[0113] Table 4. Growth score used to determine CFU / mL in test samples.

[0114] The dosed lotion formulations were adjusted to be at pH of 6.3. As shown in Table 5, the lotion formulations showed moderate bacteria contamination (i.e., rating = 3 after 21 or 28 days) and light to moderate fungi contaminations (i.e., rating = 2 or 3 after 21 or 28 days) when dosed with phenoxyethanol (POE) alone. Each of Samples 1-3 (from Table 1) and Comparative Sample A (from Table 1), dosed alone, showed no antimicrobial efficacy against either bacteria or fungi. When POE was combined with the respective Samples 1-3, significant improvement of the POE preservative efficacy was demonstrated, as the lotions showed no contamination or only light contamination after 28 days against both bacteria or fungi. In contrast, Comparative Sample A did not improve the antimicrobial efficacy when combined with POE.

[0115] The lotion formulations dosed with benzyl alcohol (BA) alone showed heavy fungi contamination (i.e., rating = 4 after 21 or 28 days) and moderate bacteria contaminations (i.e., rating = 3 after 21 or 28 days). When BA was combined with the respective Samples 1-3 (from Table 1), significant improvement of the BA preservative efficacy was demonstrated as the lotions showed no contaminations after 28 days against bacteria. In contrast, Comparative Sample A (from Table 1) did not improve the antimicrobial efficacy when combined with BA.

[0116] Table 5. Challenge test data

[0117]

[0118] Example 2: Antioxidant properties.

[0119] Antioxidant properties were studied using the activated ABTS Antioxidant Assay Kit (Cat# AOX-14) from Zen -Bio for the following experiments. The water-soluble analogue of a-tocopherol (a commonly known vitamin E antioxidant), Trolox, was used as a reference. A series of Trolox at different concentrations (0, 4.7, 9.4, 18.75, 37.5, 75, 150, and 300 pM) were used as the calibration curve for quantifying the antioxidant properties. The absorbance of the Trolox and the multifunctional additives were measured in triplicates using the Multimode Microplate Reader, BioTek Synergy Hl, at a wavelength of 405 nm. Table 6 summarizes the corresponding Trolox equivalent values of the Samples 1-3 from Table 1. The Samples showed surprisingly strong intrinsic antioxidant properties, as quantified by the pM Trolox equivalents. As a comparison, benzyl alcohol showed no antioxidant property as indicated by the low Trolox equivalent value.

[0120] Table 6. Trolox equivalents (calculated from a Trolox calibration curve)

[0121] Example 3: Chelation properties.

[0122] Chelation properties were measured using the ZenBio Cupric Ion Chelating (CIC) Assay (Cat# AOX- 16, instruction manual ZBM0125.00, July 2021). The assay measured the capacity of the samples to chelate free cupric ions in solution, thereby inhibiting Cu(II) binding to pyrocatechol violet (PV) for generating a highly colored complex. The absorbance of the Cupric -PV complex was measured at a wavelength of 632 nm. The Cupric Ion Chelating activity was determined as the percent of total PV over the Cu(II) binding. Ethylenediaminetetraacetic acid (EDTA), a well-known chelating agent, was used as a positive control. A series of EDTA with 7 different concentrations from 0 to 1000 pM were prepared and their corresponding absorbance measured and used as the calibration curve (Cupric ion chelating (%) vs. EDTA concentration). Percent Cupric ion chelating was determined applying the following calculations and equation 1. The background absorbance value was determined by averaging the absorbance values of the three background wells (no C11SO4 or sample). The average background absorbance was then subtracted from all the sample absorbance values. The maximal absorbance value (Absmax) was determined by averaging the absorbance values of the three wells containing C11SO4. PV and assay buffer. Abstest in equation 1 was the absorbance of the test sample.

[0123] Cupric ion chelating (%) = 100 x (Absmax - Abstest) / Absmax (Equation 1)

[0124] The calibration curve (Cupric ion chelating (%) vs. EDTA concentration) was fit using a polynomial curve after loglO transforming the concentrations (R2>0.98).

[0125] The chelating activity of each of Samples 1-3 from Table 1 is shown in Table 7. Based on the determined EDTA equivalents values, the Samples exhibited significant chelating properties. For comparison, neither ethylhexylglycerin (a commonly used multifunctional ingredient in personal care and cosmetic formulations) nor phenoxyethanol (a representative soft preservative commonly used in personal care and cosmetic formulations) showed chelating properties, with a negligible Cupric ion chelating (%) value (slightly negative) after subtracting the background absorbance (i.e., approximately 0 pM of the EDTA equivalent).

[0126] Table 7. EDTA equivalents

Claims

What is claimed is:

1. A personal care, cosmetic or home care product composition comprising an antimicrobial preservative and an antimicrobial booster agent comprising at least one ether compound of formula (I)wherein R is hydroxyl, an unsubstituted or substituted Ci-Cs alkoxy or an unsubstituted or substituted C2-C8 alkenyloxy, or R taken together with the carbon atom to which it is bonded forms an aldehyde, an unsubstituted or substituted Ci-Cs alkyl ester or an unsubstituted or substituted C2-C8 alkenyl ester, and n is from 3 to 30.

2. The product composition of claim 1, wherein R is hydroxyl, C1-C4 alkoxy, or C2-C4 alkenyloxy.

3. The product composition of claim 1, wherein R is hydroxyl.

4. The product composition of any one of claims 1-3, wherein n is 3 to 20.

5. The product composition of any preceding claim, wherein the antimicrobial booster agent comprises a mixture of ether compounds of formula (I).

6. The product composition of claim 5, wherein the mixture of ether compounds of formula (I) contains at least two compounds differing from one another at least in the value for n.

7. The product composition of claim 6, wherein the mixture of ether compounds of formula (I) contains at least three compounds differing from one another at least in the value for n.

8. The product composition of any preceding claim, wherein the antimicrobial preservative comprises an isothiazolinone, an alkylhydroxamic acid and / or salt thereof, an aromatic aldehyde, an alcohol, a diol, a glyceryl ether, an aromatic ether, a pyrithione, an organic acid, a salt and / or ester of an organic acid, ethyl lauroyl arginate (LAE), or a combination thereof, preferably wherein the antimicrobial preservative comprises an isothiazolinone, an aromatic aldehyde, an aromatic alcohol, an aromatic ether, an organic acid, a salt or ester of an organic acid, a pyrithione, ethyl lauroyl arginate (LAE) or a combination thereof.

9. The product composition of any preceding claim, wherein the antimicrobial preservative comprises an alkylhydroxamic acid and / or salt thereof, phenoxyethanol, benzyl alcohol, hydroxyacetophenone, dichlorobenzyl alcohol, phenethyl alcohol, cinnamic aldehyde, cinnamic alcohol, 1,2-propanediol, 1,3 -butanediol, 1,2-pentanediol, 1,2-hexanediol, 1,2-heptanediol, 1,2- octanediol, bronopol, ethylhexylglycerin, chlorphenesin, CMIT, MIT, BIT, benzoic acid, propionic acid, salicylic acid, sorbic acid, formic acid, citric acid, hexa-2,4-dienoic acid, 4-hydroxybenzoic acid, a salt and / or ester of the foregoing acids, zinc pyrithione, sodium pyrithione, or a combination thereof.

10. The product composition of any preceding claim, wherein the composition comprises the at least one ether compound of formula (I) in an amount of from about 0.01 wt% to about 5 wt%, based on the total weight of the product composition.

11. The product composition of any preceding claim, wherein the at least one ether compound of formula (I) has at least an antioxidant property, at least a chelating property or a combination thereof.

12. A method of providing antimicrobial activity to a personal care, cosmetic or home care product composition, comprising adding to the composition an antimicrobial preservative and an antimicrobial booster agent comprising at least one ether compound of formula (I)wherein R is hydroxyl, an unsubstituted or substituted Ci-Cs alkoxy or an unsubstituted or substituted C2-C8 alkenyloxy, or R taken together with the carbon atom to which it is bonded forms an aldehyde, an unsubstituted or substituted Ci-Cs alkyl ester or an unsubstituted or substituted C2-C8 alkenyl ester, and n is from 3 to 30.

13. Use of an antimicrobial booster agent comprising at least one ether compound of formula (I) for enhancing the antimicrobial efficacy of an antimicrobial preservative in a personal care, cosmetic or home care product composition:wherein R is hydroxyl, an unsubstituted or substituted Ci-Cs alkoxy or an unsubstituted or substituted C2-C8 alkenyloxy, or R taken together with the carbon atom to which it is bonded forms an aldehyde, an unsubstituted or substituted Ci-Cs alkyl ester or an unsubstituted or substituted C2-C8 alkenyl ester, and n is from 3 to 30.

14. An antimicrobial composition comprising an antimicrobial preservative and an antimicrobial booster agent comprising at least one ether compound of formula (I)wherein R is hydroxyl, an unsubstituted or substituted Ci-Cs alkoxy or an unsubstituted or substituted C2-C8 alkenyloxy, or R taken together with the carbon atom to which it is bonded forms an aldehyde, an unsubstituted or substituted Ci-Cs alkyl ester or an unsubstituted or substituted C2-C8 alkenyl ester, and n is from 3 to 30, and wherein at least 75 wt%, based on the total weight of active ingredients in the antimicrobial composition, constitutes the combined amount of the antimicrobial preservative and the at least one ether compound of formula (I).

15. The method, use or composition of any one of claims 12-14, wherein R is hydroxyl, C1-C4 alkoxy, or C2-C4 alkenyloxy.

16. The method, use or composition of claim 15, wherein R is hydroxyl.

17. The method, use or composition of any one of claims 12-16, wherein n is from 3 to 20.

18. The method, use or composition of any one of claims 12-17, wherein the antimicrobial booster agent comprises a mixture of ether compounds of formula (I).

19. The method, use or composition of claim 18, wherein the mixture of ether compounds of formula (I) contains at least two compounds differing from one another at least in the value for n.

20. The method, use or composition of claim 19, wherein the mixture of ether compounds of formula (I) contains at least three compounds differing from one another at least in the value for n.

21. The method, use or composition of any one of claims 12-20, wherein the antimicrobial preservative comprises an isothiazolinone, an alkylhydroxamic acid and / or salt thereof, an aromatic aldehyde, an alcohol, a diol, a glyceryl ether, an aromatic ether, a pyrithione, an organic acid, a salt and / or ester of an organic acid, ethyl lauroyl arginate (LAE), or a combination thereof, preferably wherein the antimicrobial preservative comprises an isothiazolinone, an aromatic aldehyde, an aromatic alcohol, an aromatic ether, an organic acid, a salt or ester of an organic acid, a pyrithione, ethyl lauroyl arginate (LAE) or a combination thereof.

22. The method, use or composition of claim 21, wherein the antimicrobial preservative comprises an alkylhydroxamic acid and / or salt thereof, phenoxyethanol, benzyl alcohol, hydroxyacetophenone, dichlorobenzyl alcohol, phenethyl alcohol, cinnamic aldehyde, cinnamic alcohol, 1,2-propanediol, 1,3 -butanediol, 1,2-pentanediol, 1,2-hexanediol, 1,2-heptanediol, 1,2- octanediol, bronopol, ethylhexylglycerin, chlorphenesin, CMIT, MIT, BIT, benzoic acid, propionic acid, salicylic acid, sorbic acid, formic acid, citric acid, hexa-2,4-dienoic acid, 4-hydroxybenzoic acid, a salt and / or ester of the foregoing acids, zinc pyrithione, sodium pyrithione, or a combination thereof.

23. The method, use or composition of any one of claims 12-22, wherein the at least one ether compound of formula (I) has at least an antioxidant property, at least a chelating property or a combination thereof.

24. The antimicrobial composition of claim 14, wherein at least 50 wt%, based on the total weight of the antimicrobial composition, constitutes the combined amount of the antimicrobial preservative and the at least one ether compound of formula (I).

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