TITLE OF THE INVENTION Detergent Compositions Containing Zinc Salts

CROSS REFERENCE TO RELATED APPLICATIONS

[0001] This application claims priority to U.S. Application Serial No. 61/055,499, filed on 23 May 2008, which is incorporated here in by reference.

BACKGROUND OF THE INVENTION

[0002] The present invention relates to surfactant-based cleansing compositions that are effective for cleaning, with minimum skin irritation potential. The surfactant-based compositions may be hand dishwashing liquids, liquid skin cleansers or any type of cleaning or cleansing product based on surfactants. Zinc salts have been found to decrease the skin irritation potential, even in already optimized surfactant-based product containing other types of counter-irritants such as amphoteric or nonionic secondary surfactants while maintaining antibacterial efficacy.

[0003] In formulating detergent compositions that will contact a user's skin, such as, for example, light duty liquid or gel dishwashing detergent compositions, laundry bars, personal cleansing compositions (such as shampoos and body washes) and the like, there is a need for compositions that can provide superior cleaning and antibacterial properties while being mild enough for prolonged contact with users' skin.

BRIEF SUMMARY OF THE INVENTION

[00041 A detergent composition comprising an organic zinc salt and a surfactant [0005] A detergent composition comprising:

(i) a organic zinc salt;

(ii) an amine oxide surfactant;

(iii) an ethoxylated alkyl ether sulfate surfactant; and

(iv) a solubilizer. J0006] A detergent composition comprising;

(i) about 0, 1 to about 2% of an organic zinc salt;

(ii) about 0.1 to about 10% of an amine oxide surfactant:

(iii) about 0.1 to about 30% of an ethoxylated alkyl ether sulfate surfactant; and

(iv) about 0.1 to about 30% of a solubilizer. [OCM)Tj A light duty liquid detergent composition comprising:

(i) an organic zinc salt;

(ii) ail amine oxide surfactant having the formula:

R ₁ (C ₂ H ₄ O) _n N— *~ O

R ₃ wherein

R] is an alkyl, 2-hydroxyalkyl. 3-hydroxyalkyl. or 3-alkoxy-2-hydroxypropyl radical in which the alkyl and alkoxy, respectively, contain 8 to 18 carbon atoms;

RT and R ₃ are each independently methyl, ethyl, propyl, isopropyl. 2- hydroxyethyl, 2-hydroxypropyl, or 3-hydroxypropyl; and n is O to 10;

(iii) an ethoxylated alkyl ether sulfate surfactant chosen from magnesium, sodium, potassium, ammonium and ethanolammonium salts of linear Cg-C i ₆ alkyl benzene sulfonates; C ₁₀ -C ₂₀ paraffin sulfonates, alpha olefin sulfonates containing 10 to 24 carbon atoms and Cg-C ig alkyl sulfates and mixtures thereof; and

(iv) a solubilizer chosen from C2-C ₅ mono-, di-, and polyhydroxy alkanols; urea; and alkali metal salts of cumene, toluene or xylene sulfonates and mixtures thereof; wherein the light duty liquid detergent composition exhibits reduced redness or reduced skin barrier damage than a product comprising no organic zinc salt,

[0008] A method of making a detergent composition, said method comprising the steps of combining the following:

(i) an organic zinc salt:

(ii) an amine oxide surfactant having the formula:

R ₂

R ₁ (C ₂ H ₄ O) _n -N-~*~ O

I

R ₃ wherein Ri is an alk\l, 2-hydroxyalkyl, 3-hydroxyalkyl, or 3-alkoxy-2-hydroxypropyl radical in which the alkyl and alkoxy. respectively, contain 8 to 18 carbon atoms;

R. ₂ and R ₃ are each independently methyl, ethyl, propyl, isopropyl, 2- hydroxyethyl, 2-hydroxypropyl, or 3-hydroxypropyl; and 11 is O to 10;

(iii) an ethoxylated alkyl ether sulfate surfactant chosen from magnesium, sodium, potassium, ammonium and ethanolammonium salts of linear Cg-Ci ₆ alkyl benzene sulfonates: C ₁ Q-C _2O paraffin sulfonates, alpha olefin sulfonates containing 10 to 24 carbon atoms and Cg-Cjg alkyl sulfates and mixtures thereof; and

(iv) a solubilizer chosen from C ₂ -C ₅ mono-, di-, and polyhydroxy alkanols; urea; and alkali metal salts of cumene, toluene or xylene sulfonates and mixtures thereof.

DETAILED DESCRIPTION OF THE INVENTION

[0009J As used throughout, ranges are used as a shorthand for describing each and every value that is within the range. Any value within the range can be selected as the terminus of the range. In addition, all references cited herein are hereby incorporated by reference in their entireties. In the event of a conflict in a definition in the present disclosure and that of a cited reference, the present disclosure controls.

[OOIOJ In certain embodiments, the invention relates to an antibacterial light duty liquid detergent composition with desirable cleansing properties, such as good grease cutting and excellent disinfecting properties, as well as mildness to the human skin, wherein the composition includes at least one zinc salt, at least one amine oxide surfactant, at least one ethoxylated alkyl ether sulfate surfactant, and at least one solubilizer, and optionally including at least one of an additional compound chosen from a fragrance agent, a perfume, a preservative, and an additional surfactant.

[0011] In certain embodiments, the present invention relates to an antibacterial light duty liquid cleaning composition comprising: (i) an organic zinc salt; (H) an amine oxide surfactant; (iϋ) an ethoxylated alky! ether sulfate surfactant: and (iv ) a solubilizer.

[0U12| The zinc salts used in the instant compositions may include, but are not limited to, organic zinc salts such as the following: zinc acetate, zinc gluconate, zinc glycerate, zinc glycolate, zinc formate, zinc lactate, zinc picolinate. zinc proprionate, zinc salicylate, /inc tartrate, /inc undecvlenate, /inc butyrate, /inc borate, zinc carbonate, zinc citrate, zinc lactate.

zinc oleate, zinc oxalate, zinc propionate, zinc salicylate, zinc selenate. zinc silicate, zinc stearatc, zinc tannate, zinc tartrate, zinc valerate, zinc aspartate, zinc cysteinate, zinc dibutyl carbamate, zinc lactate, zinc phenol sulfonate, zinc pyrithic sulfate, zinc undecilate and mixtures thereof.

[00131 The amine oxides useful for the compositions of the present invention include, for example, semi-polar nonionic surfactants such as, e.g., compounds and mixtures of compounds having the formula:

R ₂ R ₁ (C ₂ H ₄ O) _n N— »-0

R ₃ wherein

R] is an alkyl, 2-hydroxyalkyl, 3-hydroxyalkyl, or 3-alkoxy-2-hydroxypropyl radical in which the alkyl and alkoxy, respectively, contain from 8 to 18 carbon atoms;

RT and R ₃ are each independently methyl, ethyl, propyl, isopropyl, 2-hydroxyethyl, 2- hydroxypropyl, or 3-hydroxypropyl; n is O to 10.

[0014] In various embodiments the amine oxides have the formula:

R ₉

R ₈ N— *-0

R-19 wherein Rg is a Ct ₂ . i6 alkyl group or amido radical;

O H

_{Rii C N (CH2)n} wherein Rn is an alkyl group about 9 to 19 carbon atoms and a is an integer having a value of 1 to 4 and R., and R^ are methyl or ethyl. The abo\e ethylene oxide condensates, amides, and amine oxides are also discussed in U.S. Pat. No, 4,316.824, | 001 SJ In certain embodiments, the amine oxide may be. for example, coeoamidoprop>l dimethyl amine oxide, lauryol amine oxide or cocoamidopropyl amine oxide. In various embodiments, the concentration of the amine oxide in the instant compositions is about 1 to about 30 wt °, o, or about 4 to about 10 wt. %.

(0016] The compositioDS of the present invention also include at least one ethoxylated alkyl ether sulfate. Another anionic surfactant that may be utilized in the instant composition at a concentration of about 2 to 15% or about 4 to 14% by weight is a metal salt of an ethoxylated Cg-C ig alk) 1 ether sulfate. The ethoxylated alkyl ether sulfate may be depicted by the formula:

R-(OCH(CH ₃ )CH ₂ )X OSO ₃ M

[0017] In various embodiments, x is 1 to 22 or 1 to 10. In various embodiments, R is an alkyl group having about 8 to about 18 carbon atoms or about 12 to about 15 carbon atoms. In certain embodiments, for example, R is C^ -Ci ₄ . Co-Co and Co-is and M is an alkali metal cation such as lithium, potassium and sodium and an alkali earth metal cation such as magnesium. Other examples of anionic ethoxylated sulfate include the Cg.is ethoxylated alkyl ether sulfate salts having the formula:

R'(OCH ₂ CH ₂ )n OSO ₃ M

(0018] In certain embodiments, R' is alkyl of 8 to 18 carbon atoms and n is 1 to 22 or 1 to 5. In one embodiment, M is a sodium cation. The ethoxylated alkyl ether sulfates may be made by sulfating the condensation product of ethylene oxide and C g-is alkanol, and neutralizing the resultant product. The ethoxylated alkyl ether sulfates differ from one another in the number of carbon atoms in the alcohols and in the number of moles of ethylene oxide reacted with one mole of such alcohol. In another embodiment, ethoxylated alkyl ether sulfates contain 10 to 6 carbon atoms in the alcohols and in the alkyl groups thereof. [0019] Ethoxylated C _8-I s alkylphenyl ether sulfates containing about 2 to about 6 moles of ethylene oxide in the molecule also are suitable for use in the present niicroemulsion compositions. These detergents can be prepared by reacting an alkyl phenol with 2 to 6 moles of ethylene oxide and sulfating and neutralizing the resultant ethoxylated alkylphenol about 5 to 20%. about 16%, for example, about 13%, and the resulting composition, which will also contain free hydroxy 1 ions, will be of a pH of at least about 12, at least about 13, such as in the ranges of about 12 to 14 and about 13 to 14, for example, about 13.5 or 14. [0020] The instant cleaning compositions may contain, in various embodiments, about 0.25 wt, % to about 10 wt. %, or about 1 vvt. % to about 8 wt. %, of at least one solubilizer. Useful solubilizers include, but are not limited to, CVs mono, dihydroxy or polyhydroxy alkanols such as ethanol. isopropanol, alkylene glycols such as hexylene glycol, glycerol ethylene glycol, glycol and propylene glycol and mixtures thereof and alkali metal ciiniene or xylene sulfonates such as sodium cumene sulfonate aad sodium xylene sulfonate. The

solubilizers may be included in order to control low temperature cloud clear properties. Urea can be optionally employed in the instant composition as a supplemental solubilizer at a concentration of, in various embodiments, up to about 10 % or about 0,5 to about 8 % of the composition.

[0021] Finally, the compositions of the present invention contain water. The proportion of water in the compositions generally is in the range of about 35% to 90% or about 50% to 85% by weight of the cleaning composition.

[0022J The stabilized compositions may optionally contain one or more additional surfactants such as anionic, amphoteric, zwitterionic, nonionic, cationic, or combinations thereof. [0023] The anionic surfactant may be any of the anionic surfactants known or previously used in the art of aqueous surfactant compositions. Suitable anionic surfactants include but are not limited to alkyl sulfates, alkyl ether sulfates, alkaryl sulfonates, alkyl succinates, alkyl sulfosuccinates, N-alkoyl sarcosinates, alkyl phosphates, alkyl ether phosphates, alkyl ether carboxylates, alkylamino acids, alkyl peptides, alkoyl taurates, carboxylic acids, acyl and alkyl glutamates, alkyl isethionates, and alpha-olefin sulfonates, especially their sodium, potassium, magnesium, ammonium and mono-, di- and triethanolamine salts. The alkyl groups generally contain from 8 to 18 carbon atoms and may be unsaturated. The alkyl ether sulfates, alkyl ether phosphates and alkyl ether carboxylates may contain from 1 to 10 ethylene oxide or propylene oxide units per molecule, and in certain embodiments contain 1 to 3 ethylene oxide units per molecule.

[0024 J Examples of suitable anionic surfactants include sodium and ammonium lauryl ether sulfate (with 1 , 2, and 3 moles of ethylene oxide), sodium, ammonium, and triethanolamine lauryl sulfate, disodium laureth sulfosuccinate, sodium cocoyl isethionate, sodium C _{J 2} -C _H olefin sulfonate, sodium laureth-6 carboxylate, sodium Cj ₂ -C _1S pareth sulfate, sodium methyl cocoyl taurate, sodium dodecylbenzene sulfonate, sodium cocoyl sarcosinate, triethanolamine monolauryl phosphate, and fatty acid soaps.

[0025] The nonionic surfactant can be any of the nonionic surfactants known or previously used in the art of aqueous surfactant compositions. Suitable nonionic surfactants include but are not limited to aliphatic (Ce-Cjg) primary or secondary linear or branched chain acids, alcohols or phenols, alkyl ethoxy lates. alkyl phenol alkoxylates (especially ethoxylates and mixed cthoxy/propoxy), block alkylene oxide condensate of alkyl phenols, alkylene oxide condensates of alkanols, ethylene oxide-'propylene oxide block copolymers, semi-polar nυniomcs (e.g., amine oxides and pfaøspine oxides i, as well as alkyl amine oxides. Other suitable nonionics include mono or di alkyl alkanolamides and alky i polysaccharides.

sorbitan fatty acid esters, polyoxyethylene sorbitan fatty acid esters, polyoxyethylene sorbitol esters, polyoxyethylene acids, and polyoxyethylene alcohols. Examples of suitable nonionic surfactants include coco mono or diethanolamide, coco diglucoside, alkyl polyglucoside, cocoamidopropyl and lauramine oxide, polysorbate 20, ethoxylated linear alcohols, cctearyl alcohol, lanolin alcohol, stearic acid, glyceryl stearate, PEG-100 stearate. and oleth 20. [0026] Amphoteric and zwitterionic surfactants are those compounds which have the capacity of behaving either as an acid or a base. These surfactants can be any of the surfactants known or previously used in the art of aqueous surfactant compositions. Suitable materials include but are not limited to alkyl betaines, alkyl amidopropyl betaines, alkyl sulphobetaines, alkyl glycinatcs, alkyl carboxyglycinates, alkyl amphopropionates, alkyl amidopropyl hydroxysultaines, acyl taurates and acyl glutamates wherein the alkyl and acyl groups have from 8 to 18 carbon atoms. Examples include cocoamidopropyl betaine, sodium cocoamphoacetate, cocoamidopropyl hydroxysultaine, and sodium cocamphopropionate. [0027] The cationic surfactants can be any of the cationic surfactants known or previously used in the art of aqueous surfactant compositions. Suitable cationic surfactants include but are not limited to alkyl amines, alkyl imidazolines, ethoxylated amines, quaternary compounds, and quaternized esters. In addition, alkyl amine oxides can behave as a cationic surfactant at a low pH. Examples include lauramine oxide, dicetyldimonium chloride, cetrimonium chloride and the like.

[0028] Other surfactants that can be utilized in the present invention are set forth in more detail in WO 99/21530. U.S. Pat. No. 3.929,678; U.S. Pat. No. 4,565,647; U.S. Pat. No. 5,720,964; and U.S. Pat. No. 5,858,948. Other suitable surfactants are described in McCutcheon's Emulsifiers and Detergents (North American and International Editions, by Schwartz, Perry and Berch).

[0029] While amounts of the additional optional surfactant can vary widely, in various embodiments, the amount is about 1% to about 80%, about 5% to about 65%, about 6% to about 30% or about 8% to 20% weight based upon the total weight of the composition. [CM)SOJ In certain embodiments, the compositions of the present invention are directed to light duty liquid detergents especially useful for household applications such as cleaning dishes and utensils. However, the compositions of the present invention have a wide number of applications such as personal care applications, home care applications, industrial and institutional applications, pharmaceutical applications, textile compounds, and the like, {0031] Examples of various personal care applications include products such as the following: Shampoos. Skin and Body Cleansers. Creams and Lotions, or Skin and Hair Cjeis.

|(MB2] Examples of home care applications include products such as: home care and industrial and institutional applications, such as laundry detergents; dishwashing detergents (automatic and manual); hard surface cleaners; hand soaps, cleaners and sanitizers; polishes, protectants, and the like.

[0033) Examples of pharmaceutical applications include topical formulations in the form of creams, lotions, ointments, or gels, where the surfactant may be used as a wetting aid for the pharmaceutically active material, or as a skin penetration enhancer, or as an emulsifier for a solvent phase having an aesthetic effect, or present to enhance the solubility or bioavailability of the pharmaceutically active material.

[0034] In addition to the previously mentioned useful constituents of the light duty liquid detergents, one may also employ normal and conventional adjuvants, provided they do not adversely affect the properties of the detergents. Thus there may be used a cationic antibacterial agent, coloring agents and perfumes; polyethylene glycol, ultraviolet light absorbers such as the Uvinuls, which are products of GAF Corporation; pH modifiers; etc. The proportion of such adjuvant materials, in total will normally not exceed 15% by weight of the detergent composition, and the percentages of illustrative examples of such individual components will be about 5% by weight.

[0035] In various embodiments, the compositions of the present invention may include preservatives. Examples of useful preservatives include, e.g., formalin, cis l-(3-chloroallyl)- 3,5,7-triaza-l-azoniaadamantane chloride, hexahydro-l,3,5-tris (2-hydroxyethyl)-s-triazine, 4,4-dimethyl-oxazolidine, 5-hydroxymethoxymethyl-l-l aza-3,7-dioxabicyclo-octane, dimethyloldimethyldantoin, N,N"-methylene bis [N'-[hydroxymethyl)-2,5-dioxo-4- imidazolidinyljurea], N-(hydroxymethyl)-N-(l,3-dihydroxymethyl-2,5-dioxo-4- imidazolidinyl)-N'-(hydroxymethyl) urea, and l,3-bis(hydroxymethyl)-5,5- dimethylimidazolidine-2,4-dione, or sodium formate or formalin or those known commercially as Quaternium 15 (Dowicil 75). In certain embodiments, the preservative may be l ,3-dimethvlol-5.5-dimethyl hydantoin (DMDMH). In various embodiments, the preservative is present in an amount of about 0.0! to about 2% or about 0.1 to about 1,5% by weight of the composition.

[0036J The present light duty liquid detergents such as dishwashing liquids are readily made by simple mixing methods from readily available components which, on storage, do not adversely affect the entire composition. A solubilizing agent such as ethanol. hexylene glycol, sodium chloride and/or sodium xylene or sodium xylene sulfonate may be used to assist in solubilizing the surfactants, fn certain embodiments, the viscosity of the light duty

liquid composition will be at least about 100 centipoises (cps) at room temperature, but may be up to about 1.000 centipoises as measured with a Brooktleld Viscometer using a number 21 spindle rotating at 20 rpm. The viscosity of the light duty liquid composition may approximate those of commercially acceptable light duty liquid compositions now on the market. The viscosity of the light duty liquid composition and the light duty liquid composition itself remain stable on storage for lengthy periods of time, without color changes or settling out of any insoluble materials. The pH of the composition is, in various embodiments, about 3 to about 8, about 4 to about 7.8 or about 4.5 to about 7.5. The pH of the composition can be adjusted by the addition of, for example, Na ₂ O (caustic soda) to the composition.

[0037 J The following examples illustrate liquid cleaning compositions of the described invention. Unless otherwise specified, all percentages are by weight. The exemplified compositions are illustrative only and do no limit the scope of the invention. Unless otherwise specified, the proportions in the examples and elsewhere in the specification are by weight. It will be understood by those of skill in the art that numerous and various modifications can be made without departing from the spirit of the present invention. Therefore, it should be clearly understood that the forms of the present invention described herein are illustrative only and are not intended to limit the scope of the invention.

Example 1

[0038] Example 1 illustrates illustrative ultra light duty liquid detergent formulations with and without l,3-bis(liydroxymeth\l)-5.5-dimethylimidazolidine-2,4-dione (DMDM hydantoin or DMDMH) and zinc chloride salt at a pH of about 6.5 to about 7.5. Example 1 illustrates illustrative embodiments containing zinc chloride salt resulted in the largest preservative effect as illustrated by micro-robustness test (MRT). The addition of zinc chloride appeared to increase the preservative effect in the formulations.

Example 2

[0039] Example 2 illustrates illustrative traditional light duty liquid detergent formulations with and without formalin and zinc citrate salt at a pH of about 6.5 to about 7.5, Example 2 illustrates that illustrative embodiments containing zinc chloride salt resulted in the largest preservative effect as illustrated by microrobustness test (MRT). The following compositions are reported in % Active Ingredients. The addition of zinc citrate appeared to increase the preservative effect in the formulations.

Example 3

[0040] Example 3 illustrates illustrative light liquid detergent formulations with and without zinc oxide nanopaiticles arid zinc citrate salt at varying pH. Example 3 illustrates embodiments containing /ϊπe oxide nanopaiticles precipitated at pH above about 6.5. while zinc citrate remains soluble e\en at neutral and alkaline pH. Example 2 also illustrates that illustrative embodiments containing amounts of zinc citrate greatly improves the mildness of dish washing liquids

ϊ I

[0042] The Frosch-Kligman Soap Chamber Test with samples diluted at 1.5% w/v, Formula B with 0.26% Zinc Citrate caused less skin surface dehydration and less alteration to the skin banner than Formula A (without zinc citrate).

Example 4

[0043J Example 4 illustrates illustrative light duty liquid deterg ^» ent formulations with various zinc salts at pH . 5.

[01144 J The Fiosch-Kligman Soap Chamber lest with samples diluted at 50% w/\. Pioducts

E, F, G and II (with organic salts of zinc) resulted in less redness and less skin barrier damage than product D (without zinc salt).

Example 5

J0045] Example 5 illustrates illustrative light duty liquid detergent formulations with and without zinc citrate salt at var> ing pH. Example 5 illustrates that embodiments containing zinc citrate caused less irritation than embodiments without zinc citrate.

[0046] The Frosch-Kligman Soap Chamber Test with samples diluted at 1.5% w/v, product K (with zinc citrate) caused less redness than product J (without zinc salt).