WO2021223222A1

WO2021223222A1 - Liquid laundry detergent composition

Info

Publication number: WO2021223222A1
Application number: PCT/CN2020/089221
Authority: WO
Inventors: Haiyan Huang; Yijia CAO; Jiayao LU
Original assignee: The Procter & Gamble Company
Priority date: 2020-05-08
Filing date: 2020-05-08
Publication date: 2021-11-11
Also published as: CN114929847A; JP2023506052A; WO2021223552A1; EP4146776A1

Abstract

A liquid laundry detergent with improved malodor control benefit is provided, which contains from about 0.001 wt%to about 5 wt%of a hindered phenol antioxidant and a specific surfactant system including both nonionic (NI) surfactant (s) and anionic (AI) surfactant (s) at an NI-to-AI weight ratio of about 1-20.

Description

LIQUID LAUNDRY DETERGENT COMPOSITION

FIELD OF THE INVENTION

The present invention relates to a cleaning composition, and particularly a liquid laundry detergent composition that is useful for treating fabrics with improved malodor control benefit.

BACKGROUND OF THE INVENTION

Laundry wash processes are designed to eliminate soils and stains from fabrics. Some soils and stains can generate malodors on fabrics. In some instances, these malodors can persist even after the laundry wash operation.

There is a continuing need to provide laundry detergent products with improved malodor control and reduction benefit, without increasing the total surfactant content therein or enlarging the environmental “footprint” thereof.

SUMMARY OF THE INVENTION

It is a surprising discovery of the present invention that when the liquid laundry detergent compositions employ a hindered phenol antioxidant in combination with a specific surfactant system, i.e., one that contains both nonionic (NI) and anionic (AI) surfactants at a relatively high NI-to-AI weight ratio, the resulting malodor control and reduction benefit is further improved in comparison with liquid laundry detergent compositions that contain the same hindered phenol antioxidant but in a different surfactant system (e.g., with a lower NI-to-AI weight ratio) . Further, presence of the hindered phenol antioxidant in the liquid laundry detergent compositions of the present invention may further improve perfume release from such compositions.

In one aspect, the present invention relates to a liquid laundry detergent composition comprising:

a) from about 0.001 wt%to about 5 wt%of a hindered phenol antioxidant;

b) from about 5 wt%to about 60 wt%of one or more nonionic (NI) surfactants; and

c) from about 1 wt%to about 45 wt%of one or more anionic (AI) surfactants,

while the NI-to-AI weight ratio ranges from 1 to 20.

In a particularly preferred embodiment, the present invention relates to a liquid laundry detergent composition comprising:

1) from about 0.02 wt%to about 0.5 wt%of a hindered phenol antioxidant selected from the group consisting of C ₁-C ₂₂ linear alkyl esters of 3, 5-bis (1, 1-dimethylethyl) -4-hydroxy-benzenepropanoic acid and mixtures thereof;

2) from about 10 wt%to about 40 wt%of a nonionic surfactant (NI) selected from the group consisting of C ₈-C ₁₈ alkyl ethoxylated alcohols having a weight average degree of ethoxylation ranging from about 7 to about 10 and mixtures thereof; and

3) from about 5 wt%to about 20 wt%of a C ₁₀-C ₂₀ linear alkyl benzene sulphonate (LAS) and a C ₁₀-C ₂₀ linear or branched alkylethoxy sulfate (AES) having a weight average degree of ethoxylation ranging from about 1 to about 3,

wherein the weight ratio of NI to LAS+AES ranges from about 1.5 to about 8.

The present invention may also relate to the use of above-described liquid laundry detergent composition for treating fabrics.

These and other features of the present invention will become apparent to one skilled in the art upon review of the following detailed description when taken in conjunction with the appended claims.

DETAILED DESCRIPTION OF THE INVENTION

As used herein, the articles "a" and "an" when used in a claim, are understood to mean one or more of what is claimed or described.

As used herein, the terms “comprising, ” “comprises, ” "include" , "includes" and "including" are meant to be non-limiting.

As used herein, the term “substantially free of” or “substantially free from” means that the indicated material is present in an amount of no more than about 5 wt%, preferably no more than about 2%, and more preferably no more than about 1 wt%.

As used therein, the term “essentially free of” or “essentially free from” means that the indicated material is at the very minimal not deliberately added to the composition, or preferably not present at an analytically detectible level in such composition. It may include compositions in which the indicated material is present only as an impurity of one or more of the materials deliberately added to such compositions.

As used herein, the term “liquid” refers to a fluid having a liquid having a viscosity of from about 1 to about 2000 mPa*s at 25℃ and a shear rate of 20 sec- ¹. In some embodiments, the viscosity of the liquid may be in the range of from about 200 to about 1000 mPa*s at 25℃ at a shear rate of 20 sec- ¹. In some embodiments, the viscosity of the liquid may be in the range of from about 200 to about 500 mPa*s at 25℃ at a shear rate of 20 sec- ¹.

Unless otherwise specified, the term "molecular weight" as used herein refers to the weight average molecular weight (MWw) of the polymer chains in a polymer composition, which may be calculated using the equation:

MWw = (Σi Ni Mi ²) / (Σi Ni Mi)

wherein Ni is the number of molecules having a molecular weight Mi.

Unless otherwise specified, the term “alkyl” as used herein means a hydrocarbyl moiety which can be linear or branched, substituted or unsubstituted.

As used herein, the term “hydrocarbyl” is defined herein as any organic unit or moiety which is comprised of carbon atoms and hydrogen atoms. Included with the definition of “hydrocarbyl” are the aromatic (aryl) and non-aromatic carbocyclic rings. Further included within the term hydrocarbyl are heterocycles. The term “heterocycle” includes both aromatic (heteroaryl) and non-aromatic heterocyclic rings.

All temperatures herein are in degrees Celsius (℃) unless otherwise indicated. Unless otherwise specified, all measurements herein are conducted at 25℃ and under the atmospheric pressure. In all embodiments of the present invention, all percentages are by weight of the total composition, unless specifically stated otherwise. All ratios are weight ratios, unless specifically stated otherwise.

It is understood that the test methods that are disclosed in the Test Methods Section of the present application must be used to determine the respective values of the parameters of Applicants’ inventions are described and claimed herein.

Hindered Phenol Antioxidant

The liquid laundry detergent composition of the present invention contains at least one hindered phenol antioxidant, preferably in an amount sufficient to provide at least 25 ppb, more preferably at least 100 ppb, even more preferably at least 250 ppb, even more preferably at least 500 ppb, most preferably at least 1000 ppb, of an antioxidant concentration in the treatment liquor. Without wishing to be bound by theory, it is believed that hindered phenol antioxidants may help to improve malodor control performance of the liquid laundry detergent compositions, particularly in combination with a surfactant system with a relatively high content of nonionic surfactants according to the present disclosure.

As used herein, the term “hindered phenol” is used to refer to a compound comprising a phenol group with substituent (s) at a position ortho to at least one phenolic -OH group. Preferably, the hindered phenol antioxidant used in the present invention comprises at least one phenolic -OH group having: (a) at least one C ₃-C ₂₂ branched alkyl at a position ortho to said at least one phenolic -OH group; or (b) substitutes at each position ortho to said at least one phenolic -OH group, wherein said substitutes are independently selected from the group consisting of hydroxy, C ₁-C ₆ alkoxy, C ₁-C ₂₂ linear alkyl, and combinations thereof.

Examples of such hindered phenol antioxidants may include, but are not limited to: 2, 6-bis (1-methylpropyl) phenol; 2, 6-bis (1, 1-dimethylethyl) -4-methyl-phenol (also known as hydroxy butylated toluene or “BHT” ) ; 2- (1, 1-dimethylethyl) -1, 4-benzenediol; 2, 4-bis (1, 1-dimethylethyl) -phenol; 2, 6-bis (1, 1-dimethylethyl) -phenol; 3, 5-bis (1, 1-dimethylethyl) -4-hydroxybenzene propanoic acid, methyl ester; 2- (1, 1-dimethylethyl) -4-methylphenol; 2- (1, 1-dimethylethyl) -4, 6-dimethyl-phenol; 3, 5-bis (1, 1-dimethylethyl) -4-hydroxybenzenepropanoic acid, 1, 1'- [2, 2-bis [ [3- [3, 5-bis (1, 1-dimethylethyl) -4-hydroxyphenyl] -1-oxopropoxy] methyl] -1, 3-propanediyl] ester; 3, 5-bis (1, 1-dimethylethyl) -4-hydroxybenzenepropanoic acid, octadecyl ester; 2, 2'-methylenebis [6- (1, 1-dimethylethyl) -4-methylphenol; 2- (1, 1-dimethylethyl) -phenol; 2, 4, 6-tris (1, 1-dimethylethyl) -phenol; 4, 4'-methylenebis [2, 6-bis (1, 1-dimethylethyl) -phenol; 4, 4', 4" - [ (2, 4, 6-trimethyl-1, 3, 5-benzenetriyl) tris (methylene) ] tris [2, 6-bis (1, 1-dimethylethyl) -phenol] ; N, N'-1, 6-hexanediylbis [3, 5-bis (1, 1-dimethylethyl) -4-hydroxybenzenepropanamide; 3, 5-bis (1, 1-dimethylethyl) -4-hydroxy benzoic acid, hexadecyl ester; P- [ [3, 5-bis (1, 1-dimethylethyl) -4-hydroxyphenyl] methylphosphonic acid, diethyl ester; 1, 3, 5-tris [ [3, 5-bis (1, 1-dimethylethyl) -4-hydroxyphenyl] methyl] -1, 3, 5-Triazine-2, 4, 6 (1H, 3H, 5H) -trione; 3, 5-bis (1, 1-5 dimethylethyl) -4-hydroxybenzenepropanoic acid, 2- [3- [3, 5-bis (1, 1-dimethylethyl) -4-hydroxyphenyl] -1-oxopropyl] hydrazide; 3- (1, 1-dimethyl ethyl) -4-hydroxy-5-methylbenzenepropanoic acid, 1, 1'- [1, 2-ethanediylbis (oxy-2, 1-ethanediyl) ] ester; 4- [ (dimethylamino) methyl] -2, 6-bis (1, 1-dimethylethyl) phenol; 4- [ [4, 6-bis (octylthio) -1, 3, 5-triazin-2-yl] amino] -2, 6-bis (1, 1-dimethylethyl) phenol; 3, 5-bis (1, 1-dimethylethyl) -4-hydroxy benzene propanoic acid, 1, 1'- (thiodi-2, 1-ethanediyl) ester; 3, 5-bis (1, 1-dimethylethyl) -4-hydroxybenzoic acid, 2, 4-bis (1, 1-dimethylethyl) phenyl ester; 3, 5-bis (1, 1-dimethylethyl) -4-hydroxybenzenepropanoic acid, 1, 1'- (1, 6-hexanediyl) ester; 3- (1, 1-dimethylethyl) -4-hydroxy-5-methylbenzenepropanoic acid, 1, 1'- [2, 4, 8, 10-tetraoxaspiro [5.5] undecane-3, 9-diylbis (2, 2-dimethyl-2, 1-ethanediyl) ] ester; 3- (1, 1-dimethylethyl) -b- [3- (1, 1-dimethylethyl) -4-hydroxy phenyl] -4-hydroxy-b-methylbenzenepropanoic acid, 1, 1'- (1, 2-ethanediyl) ester; 2- [ [3, 5-bis (1, 1-dimethylethyl) -4- hydroxyphenyl] methyl] -2-butylpropanedioic acid, 1, 3-bis (1, 2, 2, 6, 6-pentamethyl-4-piperidinyl) ester; 3, 5-bis (1, 1-dimethylethyl) -4-hydroxybenzenepropanoic acid, 1- [2- [3- [3, 5-bis (1, 1-dimethylethyl) -4-hydroxyphenyl] -1-oxopropoxy] ethyl] -2, 2, 6, 6-tetramethyl-4-piperidinyl ester; 3, 4-dihydro-2, 5, 7, 8-tetramethyl-2- [ (4R, 8R) -4, 8, 12-trimethyltridecyl] - (2R) -2H-1-benzopyran-6-ol; 2, 6-dimethylphenol; 2, 3, 5-trimethyl-1, 4-benzenediol; 2, 4, 6-trimethylphenol; 2, 3, 6-trimethylphenol; 4, 4'- (1-methylethylidene) -bis [2, 6-dimethylphenol] ; 1, 3, 5-tris [ [4- (1, 1-dimethylethyl) -3-hydroxy-2, 6-dimethylphenyl] methyl] -1, 3, 5-triazine-2, 4, 6 (1H, 3H, 5H) -trione; 4, 4'-methylenebis [2, 6-dimethylphenol] ; and mixtures thereof.

Additional antioxidants may be employed. Examples of suitable additional antioxidants for use include, but are not limited to, the group consisting of α-, β-, γ-, δ-tocopherol, ethoxyquin, 2, 2, 4-trimethyl-1, 2-dihydroquinoline, 2, 6-di-tert-butyl hydroquinone, tert-butyl hydroxyanisole, lignosulphonic acid and salts thereof, and mixtures thereof. It is noted that ethoxyquin (1, 2-dihydro-6-ethoxy-2, 2, 4-trimethylquinoline) is marketed under the name Raluquin ^TM by the company Raschig ^TM. Other types of antioxidants that may be used in the composition are 6-hydroxy-2, 5, 7, 8-tetramethylchroman-2-carboxylic acid (Trolox ^TM) and 1, 2-benzisothiazoline-3-one (Proxel GXL ^TM) . Antioxidants such as tocopherol sorbate, butylated hydroxyl benzoic acids and their salts, gallic acid and its alkyl esters, uric acid and its salts, sorbic acid and its salts, and dihydroxyfumaric acid and its salts may also be useful. Other useful antioxidants may include tannins, such as tannins selected from the group consisting of gallotannins, ellagitannins, complex tannins, condensed tannins, and combinations thereof.

Preferably, the hindered phenol antioxidant comprises at least one phenolic -OH group having at least one C ₃-C ₆ branched alkyl at a position ortho to said at least one phenolic -OH group. For example, the hindered phenol antioxidant may be 2, 6-bis (1, 1-dimethylethyl) -4-methyl-phenol (BHT) .

More preferably, the hindered phenol antioxidant is an ester of 3, 5-bis (1, 1-dimethylethyl) -4-hydroxy-benzenepropanoic acid, and most preferably a C ₁-C ₂₂ linear alkyl ester of 3, 5-bis (1, 1-dimethylethyl) -4-hydroxy-benzenepropanoic acid. Commercially available C ₁-C ₂₂ linear alkyl esters of 3, 5-bis (1, 1-dimethylethyl) -4-hydroxy-benzenepropanoic acid include

from Raschig USA (Texas, USA) , which is a methyl ester of 3, 5-bis (1, 1-dimethylethyl) -4-hydroxy-benzenepropanoic acid, and

TS from BASF (Ludwigshafen, Germany) , which is an octadecyl ester of 3, 5-bis (1, 1-dimethylethyl) -4-hydroxy-benzenepropanoic acid.

The hindered phenol antioxidants may also help to reduce yellowing that may be associated with amines, allowing the amines to be formulated at a relatively higher level. In this respect, it is desirable to use non-yellowing hindered phenol antioxidants, may be preferred. Antioxidants that form yellow by-products are undesirable because they may lead to perceptible negative attributes in the consumer experience (such as deposition of yellow by-products on fabric, for example) . The skilled artisan is able to make informed decisions regarding the selection of antioxidants to employ. Further,

The above-described hindered phenol antioxidant may be present in the liquid laundry detergent composition of the present invention in an amount ranging from about 0.001 wt%to about 5 wt%, preferably from about 0.005 wt%to about 2 wt%, more preferably from about 0.01 wt%to about 1 wt%, most preferably from about 0.02 wt%to about 0.5 wt%.

In a particularly preferred embodiment, the liquid laundry detergent composition contains from about 0.02 wt%to about 0.5 wt%of a C ₁-C ₂₂ linear alkyl ester of 3, 5-bis (1, 1-dimethylethyl) -4-hydroxy-benzenepropanoic acid.

Surfactant System

In addition to the hindered phenol antioxidants described hereinabove, the liquid laundry detergent composition of the present invention also includes a surfactant system comprising one or more surfactants selected from the group consisting of anionic surfactants, nonionic surfactants, zwitterionic surfactants, amphoteric surfactants, cationic surfactants, and combinations thereof. The total surfactant content of such liquid laundry detergent composition may range from about 10%to about 90%, preferably from about 10%to about 80%, more preferably from about 15%to about 60%by total weight of the composition.

It is an important feature of the present invention that the surfactant system of the liquid laundry detergent composition comprises both nonionic (NI) and anionic (AI) surfactants at a specific NI-to-AI weight ratio ranging from about 1 to about 20, preferably from about 1.1 to about 15, more preferably from about 1.2 to about 10, most preferably from about 1.5 to about 8. The total amount of NI and AI surfactants in the liquid laundry detergent composition may range from about 6 wt%to about 90 wt%, preferably from about 10 wt%to about 80 wt%, more preferably from about 12 wt%to about 60 wt%.

Nonionic surfactants that can be included into the liquid laundry detergent composition of the present invention may be any conventional nonionic surfactants, including but not limited to: alkyl alkoxylated alcohols, alkyl alkoxylated phenols, alkyl polysaccharides, polyhydroxy fatty acid amides, and the like. Preferred nonionic surfactants are those of the formula R ¹ (OC ₂H ₄) _nOH, wherein R ¹ is a C ₈-C ₁₈ alkyl group or alkyl phenyl group, and n is from about 1 to about 80. Particularly preferred are C ₈-C ₁₈ alkyl ethoxylated alcohols having a weight average degree of ethoxylation from about 1 to about 20, preferably from about 5 to about 15, more preferably from about 7 to about 10, such as

nonionic surfactants commercially available from Shell.

Other non-limiting examples of nonionic surfactants useful herein include: C ₆-C ₁₂ alkyl phenol alkoxylates where the alkoxylate units may be ethyleneoxy units, propyleneoxy units, or a mixture thereof; C ₁₂-C ₁₈ alcohol and C ₆-C ₁₂ alkyl phenol condensates with ethylene oxide/propylene oxide block polymers such as

from BASF; C ₁₄-C ₂₂ mid-chain branched alcohols (BA) ; C ₁₄-C ₂₂ mid-chain branched alkyl alkoxylates, BAE _x, wherein x is from 1 to 30; alkyl polysaccharides, specifically alkyl polyglycosides; Polyhydroxy fatty acid amides; and ether capped poly (oxyalkylated) alcohol surfactants. Suitable nonionic surfactants also include those sold under the tradename

from BASF.

The nonionic surfactants can be provided in the liquid laundry detergent compositions of the present invention at levels ranging from about 5 wt%to about 60 wt%, preferably from about 8 wt%to about 50 wt%, more preferably from about 9 wt%to about 45 wt%, most preferably from about 10 wt%to about 40 wt%. In one particularly preferred embodiment, the liquid laundry detergent composition contains from about 10 wt%to about 40 wt%of a C ₈-C ₁₈ alkyl ethoxylated alcohol having a weight average degree of ethoxylation ranging from about 7 to about 10.

Anionic surfactants that are used in the liquid laundry detergent compositions of the present invention are preferably non-soap synthetic anionic surfactants, such as the water-soluble salts, preferably the alkali metal salts and/or ammonium salts, of organic sulphonic reaction products having in their molecular structure an alkyl group (included in the term "alkyl" is the alkyl portion of acyl groups) containing from about 10 to about 20 carbon atoms and a sulphonic/phosphonic acid or sulfuric/phosphoric acid ester group. Examples of suitable synthetic anionic surfactants include, but are not limited to: C ₁₀-C ₂₀ linear alkyl benzene sulphonates, C ₁₀-C ₂₀ linear or branched alkyl sulfates, C ₁₀-C ₂₀ linear or branched alkylethoxy sulfates having a weight average degree of ethoxylation ranging from 0.1 to 5.0, C ₁₀-C ₂₀ linear or branched alkyl ester sulfates, C ₁₀-C ₂₀ linear or branched alkyl sulphonates, C ₁₀-C ₂₀ linear or branched alkyl ester sulphonates, C ₁₀-C ₂₀ linear or branched alkyl phosphates, C ₁₀-C ₂₀ linear or branched alkyl phosphonates, C ₁₀-C ₂₀ linear or branched alkyl carboxylates, and combinations thereof (including their sodium, potassium, and/or ammonium salts) .

Especially preferred for the practice of the present invention are anionic surfactants containing C ₁₀-C ₂₀ linear alkyl benzene sulphonates (LAS) and C ₁₀-C ₂₀ linear or branched alkylethoxy sulfates (AES) having a weight average degree of ethoxylation ranging from about 0.1 to about 5, preferably from about 0.5 to about 4, more preferably from about 1 to about 3. In a particularly preferred embodiment of the present invention, the liquid laundry detergent composition comprises both the LAS and AES.

The anionic surfactants can be provided in the liquid laundry detergent compositions of the present invention at levels ranging from about 1 wt%to about 45 wt%, more preferably from about 2 wt%to about 30 wt%, more preferably from about 3 wt%to about 25 wt%, and most preferably from about 5 wt%to about 20 wt%. In one particularly preferred embodiment, the liquid laundry detergent composition contains from about 5 wt%to about 20 wt%of LAS and AES, while the AES has a weight average degree of ethoxylation ranging from about 1 to about 3. The weight ratio between LAS and AES preferably ranges from 1: 2 to 8: 1, preferably from 1: 1 to 5: 1, more preferably from 1.5: 1 to 4: 1. Most preferably, the NI-to- (LAS+AES) weight ratio ranges from about 1.5 to about 8.

Other surfactants useful herein include amphoteric surfactants, zwitterionic surfactants and cationic surfactants. Such surfactants are well known for use in laundry detergents and are typically present at levels from about 0.1 wt%, 0.2 wt%or 0.5 wt%to about 5 wt%, 10 wt%or 20 wt%.

In a preferred but not necessary embodiment of the present invention, the liquid laundry detergent composition further contains from about 0.2 wt%to about 10 wt%of one or more amphoteric and/or zwitterionic surfactants.

Preferred amphoteric surfactants are selected from the group consisting of amine oxide surfactants, such as, for example, alkyl dimethyl amine oxide or alkyl amido propyl dimethyl amine oxide, more preferably alkyl dimethyl amine oxide and especially coco dimethyl amino oxide. Amine oxide may have a linear or mid-branched alkyl moiety. Typical linear amine oxides are characterized by a formula R ₁–N (R ₂) (R ₃) -O, wherein R ₁ is a C _8-18 alkyl, and wherein R ₂ and R ₃ are independently selected from the group consisting of C _1-3 alkyls and C _1-3 hydroxyalkyls, such as methyl, ethyl, propyl, isopropyl, 2-hydroxethyl, 2-hydroxypropyl and 3-hydroxypropyl. As used herein “mid-branched” means that the amine oxide has one alkyl moiety having n1 carbon atoms with one alkyl branch on the alkyl moiety having n2 carbon atoms. The alkyl branch is located on the α carbon from the nitrogen on the alkyl moiety. This type of branching for the amine oxide is also known in the art as an internal amine oxide. The total sum of n1 and n2 is from about 10 to about 24 carbon atoms, preferably from about 12 to about 20, and more preferably from about 10 to about 16. The number of carbon atoms for the one alkyl moiety (n1) should be approximately the same number of carbon atoms as the one alkyl branch (n2) such that the one alkyl moiety and the one alkyl branch are symmetric. As used herein “symmetric” means that | n1 –n2 | is less than or equal to 5, preferably 4, most preferably from 0 to 4 carbon atoms in at least about 50 wt%, more preferably at least about 75 wt%to about 100 wt%, of the mid-branched amine oxides for use herein. Particularly preferred amphoteric surfactants are C ₁₀-C ₁₄ alkyl dimethyl amine oxides.

Preferred zwitterionic surfactants are betaine surfactants, such as, for example, alkyl betaines, alkylamidobetaines, amidazoliniumbetaines, sulfobetaines (also referred to as sultaines) as well as phosphobetaines. A particularly preferred betaine is cocoamidopropylbetaine.

Water-soluble salts of the higher fatty acids, i.e., "soaps" , are also useful anionic surfactants in the liquid laundry detergent compositions of the present invention, although such soaps are not counted when calculating the NI-to-AI weight ratio in the present invention. Suitable soaps include alkali metal salts (such as the sodium, potassium, ammonium, and alkyl ammonium salts) of higher fatty acids containing from about 8 to about 24 carbon atoms, and preferably from about 12 to about 18 carbon atoms. Soaps can be made by direct saponification of fats and oils or by the neutralization of free fatty acids. Particularly useful are the sodium and potassium salts of the mixtures of fatty acids derived from coconut oil and tallow, i.e., sodium or potassium tallow and coconut soap. However, the liquid laundry detergent compositions of the present invention preferably contain soaps at a relatively low level, e.g., no more than about 6 wt%, more preferably not more than about 2 wt%or 1 wt%, and most preferably said liquid laundry detergent compositions are substantially or essentially free of soaps.

Liquid Laundry Detergent Compositions

The liquid laundry detergent composition of the present invention is suitable for fabric cleaning application, including automatic machine washing or hand-washing of fabrics, or cleaning auxiliaries, such as for example, bleach, rinse aids, additives or pre-treat types.

The liquid laundry detergent composition can be a fully formulated laundry detergent product. Liquid compositions contained in encapsulated and/or unitized dose products are included, as are compositions which comprise two or more separate but jointly dispensable portions. Preferably, the liquid laundry detergent composition contains water as an aqueous carrier, and it can contain either water alone or mixtures of organic solvent (s) with water as carrier (s) . Suitable organic solvents are linear or branched lower C ₁-C ₈ alcohols, diols, glycerols or glycols; lower amine solvents such as C ₁-C ₄ alkanolamines, and mixtures thereof. Exemplary organic solvents include 1, 2-propanediol, ethanol, glycerol, monoethanolamine and triethanolamine. The carriers are typically present at levels in the range of from about 0.1%to about 98%, preferably from about 10%to about 95%, more preferably from about 25%to about 75%by total weight of the liquid laundry detergent composition. In some embodiments, water is from about 85 to about 100 wt%of the carrier. In other embodiments, water is absent and the composition is anhydrous. Highly preferred compositions afforded by the present invention are clear, isotropic liquids.

The liquid laundry detergent composition of the present invention has a viscosity from about 1 to about 2000 centipoise (1-2000 mPa·s) , or from about 200 to about 800 centipoises (200-800 mPa·s) . The viscosity can be determined using a Brookfield viscometer, No. 2 spindle, at 60 RPM/s, measured at 25℃.

The liquid laundry detergent composition of the present invention is preferably characterized by a pH value of no more than 9, preferably no more than 8.7, more preferably no more than 8.5. Such pH value is measured by using the liquid laundry detergent composition as a neat (i.e., undiluted) product. If the pH value of the liquid laundry detergent composition is too high, the hindered phenol antioxidant may become destabilized to yield yellow by-products that may result in undesirable color shift of the composition.

In addition to the ingredients described hereinabove, the liquid laundry compositions of the present invention may comprise an external structurant, which may be present in an amount ranging from about 0.001%to about 1.0%, preferably from about 0.05%to about 0.5%, more preferably from about 0.1%to about 0.3%by total weight of the composition. A particularly preferred external structurant for the practice of the present invention is hydrogenated castor oil, which is also referred to as trihydroxylstearin and is commercially available under the tradename

In addition to those ingredients described hereinabove, the balance of the liquid laundry detergent composition of the present invention typically contains from about 5 wt%to about 70 wt%, or about 10 wt%to about 60 wt%of adjunct ingredients. Suitable adjunct ingredients for laundry detergent products include: builders, chelating agents, dye transfer inhibiting agents, dispersants, rheology modifiers, enzymes, and enzyme stabilizers, catalytic materials, bleach activators, hydrogen peroxide, sources of hydrogen peroxide, preformed peracids, polymeric dispersing agents, clay soil removal/anti-redeposition agents, brighteners, suds suppressors, dyes, photobleaches, structure elasticizing agents, fabric softeners, carriers, hydrotropes, processing aids, solvents, hueing agents, anti-microbial agents, perfumes (including neat perfume oils and/or perfume microcapsules) , and/or pigments. The precise nature of these adjunct ingredients and the levels thereof in the liquid laundry detergent composition will depend on factors like the specific type of the composition and the nature of the cleaning operation for which it is to be used.

The liquid laundry detergent composition of the present invention may be formed by any suitable process. For example, it can be formed by mixing the above-mentioned ingredients simultaneously or sequentially. In a preferred embodiment, the hindered phenol antioxidant is added as a part of an emulsified pre-mixture that is formed by mixing the hindered phenol antioxidant with an emulsifier. Further, in order to stabilize the hindered phenol antioxidant and protect it against alkalinity during the manufacturing process, it is desirable to add a small amount of weak acid into the pre-mixture.

Methods of Using the Liquid Laundry Detergent Composition

The present invention in one aspect is directed to a method of using the above-described liquid laundry detergent composition for treating fabrics, the method comprising the steps of: (i) providing a liquid laundry detergent composition as described above; (ii) forming a laundry liquor by diluting the liquid laundry detergent composition with water; (iii) washing fabric in the laundry liquor; and (iv) rinsing the fabric in water.

Machine laundry methods may comprise treating soiled fabrics with an aqueous wash solution in a top-loading or front-loading automatic or semi-automatic washing machine having dissolved or dispensed therein an effective amount of a liquid laundry cleaning composition in accord with the invention. An “effective amount” of the liquid laundry detergent composition means from about 10g to about 300g of product dissolved or dispersed in a wash solution of volume from about 5L to about 65L. The water temperatures may range from about 5℃ to about 100℃. The water to soiled fabric ratio may be from about 1: 1 to about 30: 1. The liquid laundry detergent compositions may be employed at concentrations of from about 200 ppm to about 15,000 ppm in solution. The detergent dosage levels may also vary depending not only on the type and severity of the soils and stains, but also on the wash water temperature, the volume of wash water, and the type of washing machine (e.g., top-loading, front-loading, vertical-axis Japanese-type automatic washing machine) .

The liquid laundry detergent compositions herein may be used for laundering of fabrics at reduced wash temperatures. These methods of laundering fabric comprise the steps of delivering a liquid laundry detergent composition to water to form a wash liquor and adding a laundering fabric to said wash liquor, wherein the wash liquor has a temperature of from about 0℃ to about 20℃, or from about 0℃ to about 15℃, or from about 0℃ to about 9℃. The fabric may be contacted to the water prior to, or after, or simultaneous with, contacting the liquid laundry detergent composition with water.

Hand washing/soak methods, and combined handwashing with semi-automatic washing machines, are also included.

TEST METHODS

A. Malodor Reduction Test Method

The following method is used to test the malodor reduction benefits of a composition.

Fatty acids and malodor markers are added into 100 ml glass gar with Teflon-lined cap according to Table A and mixed well using a vortex.

Table A. Malodor marker composition

Body Soil Malodor Composition is then prepared by adding the specified amount of each material according to Table B into a 200 mL glass jar with Teflon lined cap. Artificial body soil (ABS) is commercially available by Accurate Product Development; 2028 Bohlke Blvd, Fairfield, OH 45014.

Table B. Body soil malodor composition

Next, sixteen (16) malodor test fabrics per wash load are prepared by applying 300 μl of Body soil malodor composition described in Table B to de-sized 2X5 inch white polycotton 50/50 (PCW50/50) swatches. About 51 grams of each liquid laundry detergent to be tested (see, e.g., Example 1, Table 1) is added to Japan National top loading automatic washing machine set to Normal cycle; 68 °F wash cycle followed by a 68 °F rinse cycle. Cincinnati, OH, USA soft water is mixed with hard water at known ratio to meet hardness target -This is done automatically by mixing station equipment installed on washing machines and coded algorithm. Malodor test fabrics are washed in 3gpg wash water with 2.7 kg, 50 X 50 cm clean cotton and poly-cotton ballast then dried in a Maytag tumble drier set to low for 20 minutes. The dried fabrics are placed in a mylar bag and sealed for 24 hours.

Subsequently, the malodor reduction using ABS/Squalene malodor sensors are quantitatively determined by Gas Chromatography Mass Spectroscopy using an Agilent gas chromatograph 7890B equipped with a mass selective detector (5977B) , a Chemstation quantitation package and a Gerstel multi-purpose sampler equipped with a solid phase micro-extraction (SPME) probe. Calibration standards of 6-Methyl-5-hepten-2-one (CAS 110-93-0) , Trans-2-heptenal (18829-55-5) and 3-methyl-2-Butenal (107-86-8) are prepared by dissolving a known weight of these materials in light mineral oil (CAS 8020-83-5) (each material available from Sigma Aldrich) . Fabrics are cut into uniform 2 inch by 2.5 inch pieces and placed in 10 mL headspace crimp vials. Vials are equilibrated greater than 12 hours before analysis. The following settings are used in the auto sampler: 80 C incubation temperature, 90 min incubation time, VT32-10 sample tray type, 22 mm vial penetration, 20 min extraction time, 54mm injection penetration and 300 s desorption time. The following settings are used for the Front Split/Splitless inlet helium: split mode, 250 C temperature, 12 psi pressure, 79.5 mL/min total flow, 3 mL/min septum purge flow, 50: 1 split ratio and 22.5 min GC run time. The follow settings are used in the oven: 40C initial temperature, 12C/min heating program, 250C temperature and 5 min hold time. Based on the partition coefficients (K at 80C) of each component, the total nMol/L liter of 6-Methyl-5-hepten-2-one (K = 3353) , Trans-2-heptenal (K=3434) , and 3-methyl-2-Butenal (K=1119) are calculated.

The values of these three measurements (in nmoles/L) are added together to provide the Total ABS/Squalene Markers (nmoles/L) for a given test leg.

The %Malodor Reduction Oxidation Products is provided as a percentage comparing the reduction of the amount of selected malodor markers as provided by the test composition compared to the (nil-antioxidant) reference composition. The value is determined as follows:

%Reduction Oxidation Products = (Markersref –Markerstest) x 100 /Markersref

Values for Markersref and Markerstest are defined as follows:

Markersref = Total ABS/Squalene Markers (nmoles/L) of the fabrics washed with the formulation without antioxidant (e.g., the reference or control formulation)

Markerstest = Total ABS/Squalene Markers (nmoles/L) of the fabrics washed with the formulation with the tested antioxidant

As the measured oxidation products are typically considered malodorous, it is believed that the greater the %reduction of oxidation products provided by a composition, the less malodorous the treated fabrics are likely to be. Therefore, greater values of %Malodor Reduction Oxidation Products are typically preferred. The compositions and processes of the present disclosure may provide a %Malodor Reduction Oxidation Products value of at least about 10%, or at least about 20%, or at least about 30%, or at least about 40%, or at least about 50%, or at least about 60%, or at least about 70%, or at least about 80%.

Malodor reduction may also be reported as the difference between Markersref and Markerstest, thereby showing an absolute difference (e.g., Delta ABS/Squalene Oxidation) .

C. Perfume Headspace Test Method

Perfume total intensity in fabric headspace are assayed using SPME (Solid Phase Micro Extraction) sampling technique and Gas Chromatography-Mass Spectrometry (GC-MS) using Agilent Technologies Gas Chromatograph 7890B system equipped with Agilent Technologies 5977B Mass Selective Detector &

J&W ^TM DB-5ms Ultra Inert Column (30 m length x 0.25 mm internal diameter x 0.25 μm film thickness) . Fabric is cut into 5 × 8 cm and slide into 20 mL headspace vial. After three presses with 2 kg weight, the headspace vials are conditioned in air on bench for 1hour and immediately sealed before analysis.

The following settings are used in the Multipurpose Auto Sampler MPS (GERSTEL) : 65℃ incubation temperature, 15min incubation time, VT15-20-CVM sample tray type, 2cm Gray-Notched SPME fiber coated with DVB/CAR/PDMS (Supelco 57299-U) , 30mm vial penetration, 5min extraction time, 43mm injection penetration and 180s desorption time. The following setting was used for Front Split/Splitless inlet helium: splitless mode, heat at 270℃, 12.9psi pressure, 1.6mL/min flow. The following setting was used for oven: 40℃ initial temperature and 0.5 min hold time, 17℃/min heating program, 270℃ and 1min hold time. The following setting was used for MSD: Full Scan mode with range of 35 to 300 m/z.

EXAMPLES

Example 1: Comparative Examples Exhibiting Impact of Different NI-to-AI Weight Ratios on Malodor Reduction Benefit of Antioxidant-Containing Liquid Laundry Detergent Compositions

Three (3) liquid laundry detergent compositions A-C are provided, among which composition A is a comparative composition, and compositions B and C are inventive compositions. All of three compositions A-C contain about 0.075 wt%of a hindered phenol antioxidant and about 22.0 wt%of surfactants including both a NI surfactant and two AI surfactants (LAS and AES) . The NI-to-AI weight ratios in these liquid laundry detergent compositions vary from about 0.5 (comparative) to 1.5 and 5 (inventive) . Following are the detailed compositional breakdown of the liquid laundry detergent compositions A-C:

TABLE 1

¹Methyl ester of 3, 5-bis (1, 1-dimethylethyl) -4-hydroxy-benzenepropanoic acid.

²A C ₁₂-C ₁₄ alkyl ethoxylated alcohol with a weight average degree of ethoxylation of 7.

³A C ₁₁-C ₁₂ linear alkylbenzene sulphonate.

⁴A C _12-14 alkyl ethoxylated sulfate with a weight average degree of ethoxylation of about 3.

To show the malodor reduction effects of the hindered phenol antioxidant in different surfactant systems with different NI-to-AI ratios, the liquid detergent compositions A-C are tested for their %Malodor Reduction Oxidation Products value (i.e., reduction vs. control compositions that contain the same ingredients but without the hindered phenol antioxidant) according to Test Method A disclosed hereinabove. Results are shown below in Table 2.

TABLE 2

Example 2: Exemplary Liquid Laundry Detergent Compositions

Liquid laundry detergent compositions 1-6 are made by mixing together the ingredients listed in the proportions shown:

TABLE 3

²Octadecyl ester of 3, 5-bis (1, 1-dimethylethyl) -4-hydroxy-benzenepropanoic acid.

³A C12-C14 alkyl ethoxylated alcohol with a weight average degree of ethoxylation of 7.

⁴A C12-C14 alkyl ethoxylated alcohol with a weight average degree of ethoxylation of 9.

⁵A C ₁₁-C ₁₂ linear alkylbenzene sulphonate.

⁶A C _12-14 alkyl ethoxylated sulfate with a weight average degree of ethoxylation of about 3.

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

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

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

Claims

A liquid laundry detergent composition comprising:

a) from 0.001 wt%to 5 wt%of a hindered phenol antioxidant;

b) from 5 wt%to 60 wt%of one or more nonionic surfactants; and

c) from 1 wt%to 45 wt%of one or more anionic surfactants,

wherein the weight ratio of said one or more nonionic surfactants to said one or more anionic surfactants ranges from 1 to 20.
The liquid laundry detergent composition of claim 1, wherein the weight ratio of said one or more nonionic surfactants to said one or more anionic surfactants ranges from 1.1 to 15, preferably from 1.2 to 10, more preferably from 1.5 to 8.
The liquid laundry detergent composition of claim 1 or 2, wherein the hindered phenol antioxidant comprises at least one phenolic -OH group having: (a) at least one C ₃-C ₂₂ branched alkyl at a position ortho to said at least one phenolic -OH group; or (b) substitutes at each position ortho to said at least one phenolic -OH group, wherein said substitutes are independently selected from the group consisting of hydroxy, C ₁-C ₆ alkoxy, C ₁-C ₂₂ linear alkyl, and combinations thereof; wherein the hindered phenol antioxidant preferably comprises at least one phenolic -OH group having at least one C ₃-C ₆ branched alkyl at a position ortho to said at least one phenolic -OH group; wherein the hindered phenol antioxidant is more preferably an ester of 3, 5-bis (1, 1-dimethylethyl) -4-hydroxy-benzenepropanoic acid; and wherein said hindered phenol antioxidant is most preferably a C ₁-C ₂₂ linear alkyl ester of 3, 5-bis (1, 1-dimethylethyl) -4-hydroxy-benzenepropanoic acid.
The liquid laundry detergent composition according to any one of the preceding claims, wherein said hindered phenol antioxidant is present in said liquid laundry detergent composition at an amount ranging from 0.005 wt%to 2 wt%, preferably from 0.01 wt%to 1 wt%, more preferably from 0.02 wt%to 0.5 wt%.
The liquid laundry detergent composition according to any one of the preceding claims, wherein said one or more nonionic surfactants are selected from the group consisting of alkyl alkoxylated alcohols, alkyl alkoxylated phenols, alkyl polysaccharides, polyhydroxy fatty acid amides, and mixtures thereof; and wherein preferably said one or more nonionic surfactants comprise a C ₈-C ₁₈ alkyl ethoxylated alcohol having a weight average degree of ethoxylation ranging from 1 to 20, preferably from 5 to 15, more preferably from 7 to 10.
The liquid laundry detergent composition according to any one of the preceding claims, wherein said one or more nonionic surfactants are present in said liquid laundry detergent composition at an amount ranging from 8 wt%to 50 wt%, preferably from 9 wt%to 45 wt%, more preferably from 10 wt%to 40 wt%.
The liquid laundry detergent composition according to any one of the preceding claims, wherein said one or more anionic surfactants are selected from the group consisting of C ₁₀-C ₂₀ linear alkyl benzene sulphonates, C ₁₀-C ₂₀ linear or branched alkyl sulfates, C ₁₀-C ₂₀ linear or branched alkylethoxy sulfates having a weight average degree of ethoxylation ranging from 0.1 to 5.0, C ₁₀-C ₂₀ linear or branched alkyl ester sulfates, C ₁₀-C ₂₀ linear or branched alkyl sulphonates, C ₁₀-C ₂₀ linear or branched alkyl ester sulphonates, C ₁₀-C ₂₀ linear or branched alkyl phosphates, C ₁₀-C ₂₀ linear or branched alkyl phosphonates, C ₁₀-C ₂₀ linear or branched alkyl carboxylates, and mixtures thereof; and wherein preferably said one or more anionic surfactants comprise a C ₁₀-C ₂₀ linear alkyl benzene sulphonate and a C ₁₀-C ₂₀ linear or branched alkylethoxy sulfate having a weight average degree of ethoxylation ranging from 0.1 to 5, preferably from 0.5 to 4, more preferably from 1 to 3.
The liquid laundry detergent composition according to any one of the preceding claims, wherein said one or more anionic surfactants are present in said liquid laundry detergent composition at an amount ranging from 2 wt%to 30 wt%, preferably from 3 wt%to 25 wt%, more preferably from 5 wt%to 20 wt%.
The liquid laundry detergent composition according to any one of the preceding claims, characterized by a pH value of no more than 9, preferably no more than 8.7, more preferably no more than 8.5.
A liquid laundry detergent composition comprising:

1) from 0.02 wt%to 0.5 wt%of a hindered phenol antioxidant selected from the group consisting of C ₁-C ₂₂ linear alkyl esters of 3, 5-bis (1, 1-dimethylethyl) -4-hydroxy-benzenepropanoic acid and mixtures thereof;

2) from 10 wt%to 40 wt%of a nonionic surfactant (NI) selected from the group consisting of C ₈-C ₁₈ alkyl ethoxylated alcohols having a weight average degree of ethoxylation ranging from 7 to 10 and mixtures thereof; and

3) from 5 wt%to 20 wt%of a C ₁₀-C ₂₀ linear alkyl benzene sulphonate (LAS) and a C ₁₀-C ₂₀ linear or branched alkylethoxy sulfate (AES) having a weight average degree of ethoxylation ranging from 1 to 3,

wherein the weight ratio of NI to LAS+AES ranges from 1.5 to 8.
Use of the liquid laundry detergent composition according to any one of the preceding claims for treating fabrics.