WO2024011342A1

WO2024011342A1 - Use of graft copolymer in adjusting viscosity of laundry detergent composition

Info

Publication number: WO2024011342A1
Application number: PCT/CN2022/104843
Authority: WO
Inventors: Hongxin GAO; Ming Tang; Renae Dianna Fossum; Dongpeng WANG; Jia PENG; Xiaoyi Ren
Original assignee: The Procter & Gamble Company
Priority date: 2022-07-11
Filing date: 2022-07-11
Publication date: 2024-01-18
Also published as: WO2024011999A1

Abstract

Use of a graft copolymer in adjusting the viscosity of a laundry detergent composition containing the graft copolymer is provided. Also, a laundry detergent composition containing the graft copolymer is provided.

Description

USE OF GRAFT COPOLYMER IN ADJUSTING VISCOSITY OF LAUNDRY DETERGENT COMPOSITION

FIELD OF THE INVENTION

The present invention relates to use of a graft copolymer in adjusting the viscosity of a laundry detergent composition containing the graft copolymer. The present invention also relates to a laundry detergent composition containing the graft copolymer.

BACKGROUND OF THE INVENTION

Managing viscosity is one of important aspects in laundry detergent formulation work so as to provide products with consumer desirable viscosity and processible in the plant. And, in some regions, consumers prefer liquid detergent products which have relatively low viscosity because consumers in these regions believe high viscosity corresponds to “messy” and difficult to manipulate. Too high viscosity also makes it hard to agitate and fill into bottles during product making. Although some known approaches including the addition of water and/or solvents have been leveraged for adjusting the viscosity, these approaches may limit the flexibility of formulation or even may not work in some certain circumstances. For example, in compact or super-compact detergent products, the tolerable amount of water and/or solvents might not be sufficient for adjusting the viscosity.

Furthermore, although some compact or super-compact detergent products themselves have appropriate viscosity, they might sometimes undergo “gelling” due to the formation of lamellar phase or hexagonal phase when they are added into water, i.e. the liquid might become extremely viscous (e.g. more than 10000 cPs, or even more than 100000 cPs) . Then, such detergent products would become difficult to be dissolved or dispersed. In this case, the cleaning performance would be significantly compromised.

Thus, there is a need for other approaches of adjusting viscosity of liquid detergent products.

SUMMARY OF THE INVENTION

It is a surprising and unexpected discovery of the present invention that a graft copolymer is useful as a viscosity-adjusting agent in liquid detergent products.

Correspondingly, the present invention in one aspect relates to the use of a graft copolymer in adjusting the viscosity of a laundry detergent composition containing the graft copolymer, wherein the graft copolymer comprising:

a) polyalkylene oxide which has a number average molecular weight of from 1000 to 20,000 Daltons and is based on ethylene oxide, propylene oxide, butylene oxide or mixtures thereof;

b) N-vinylpyrrolidone; and

c) vinyl ester derived from a saturated monocarboxylic acid containing from 1 to 6 carbon atoms and/or a methyl or ethyl ester of acrylic or methacrylic acid;

wherein the weight ratio of (a) : (b) is from 1: 0.1 to 1: 2, and

wherein the amount, by weight, of (a) is greater than the amount of (c) ;

In one embodiment according to the present application, in the graft polymer, a) the polyalkylene oxide comprises and preferably consists of ethylene oxide units, and c) the vinyl ester comprises and preferably consists of vinyl acetate.

In another embodiment according to the present application, in the graft polymer, a) the polyalkylene oxide comprises and preferably consists of ethylene oxide units and propylene oxide units, and c) the vinyl ester comprises and preferably consists of vinyl acetate.

In one embodiment according to the present application, the polyalkylene oxide has a number average molecular weight of from 1000 to 20,000 Daltons.

In one embodiment according to the present application, in the graft polymer, the weight ratio of (a) : (c) is from 1.0: 0.1 to 1.0: 0.99, preferably from 1.0: 0.3 to 1.0: 0.9.

In one embodiment according to the present application, in the graft polymer, from 1.0 mol%to 60 mol%, preferably from 20 mol%to 60 mol%, more preferably from 30 mol%to 50mol%of the grafted-on monomers of component (c) are hydrolyzed.

In one embodiment according to the present application, the graft polymer has a weight average molecular weight of from 4,000 Da to 100,000 Da, preferably from 5,000 Da to 100,000 Da, more preferably from 5,000 Da to 50,000 Da, most preferably from 8,000 Da to 20,000 Da.

In one embodiment according to the present application, the composition according to the present application comprises from about 0.01%to about 15%, preferably from about 0.05%to about 10%, more preferably from about 0.1%to about 5%, and most preferably from about 0.2%to about 3%, by weight of the composition, of the graft copolymer.

In one embodiment according to the present application, the composition according to the present application further comprises from about 1%to about 99%, preferably from about 5%to about 90%, more preferably from about 10%to about 85%, and most preferably from about 15%to about 80%, by weight of the composition, of a surfactant system. Preferably, the surfactant system may comprise C ₆-C ₂₀ linear alkylbenzene sulfonate (LAS) , C ₆-C ₂₀ alkyl sulfates (AS) , C ₆-C ₂₀ alkyl alkoxy sulfates (AAS) , C ₆-C ₂₀ methyl ester sulfonates (MES) , C ₆-C ₂₀ alkyl ether carboxylates (AEC) , a C ₆-C ₂₀ alkoxylated alcohol having a weight average degree of alkoxylation ranging from 1 to 20, a fatty acid, or any combinations thereof. More preferably, the surfactant system may comprise a C ₆-C ₂₀ alkoxylated alcohol having a weight average degree of alkoxylation ranging from 1 to 20, wherein the C ₆-C ₂₀ alkoxylated alcohol is present in an amount ranging from 15%to 50%by weight of the composition.

In another aspect, the present invention is related to a laundry detergent composition, comprising:

1) from 0.01%to 15%, by weight of the composition, a graft copolymer comprising:

b) N-vinylpyrrolidone; and

wherein the weight ratio of (a) : (b) is from 1: 0.1 to 1: 2, and

wherein the amount, by weight, of (a) is greater than the amount of (c) ; and

2) from 35%to 90%, by weight of the composition, of a surfactant system.

b) N-vinylpyrrolidone; and

wherein the weight ratio of (a) : (b) is from 1: 0.1 to 1: 2, and

wherein the amount, by weight, of (a) is greater than the amount of (c) ; and

2) from 20%to 35%, by weight of the composition, of a surfactant system comprising a nonionic surfactant,

wherein the nonionic surfactant is present in an amount ranging from 6.5%to 35%by weight of the composition.

In some embodiments, the composition according to the present application may comprise less than 15%, preferably less than 10%, more preferably less than 7%, most preferably less than 5%, of a non-aqueous solvent by weight of the composition. Preferably, the non-aqueous solvent is selected from the group consisting of ethylene glycol, 1, 2-propanediol (p-diol) , 1, 3-propanediol, methylpropanediol, butanediol, glycerine, butanetriol, pentaerythritol and any combinations.

In a particular embodiment, the composition according to the present application is a final product. In another particular embodiment, the composition according to the present application is an intermediate composition during making process.

In one embodiment according to the present application, the composition further comprises a treatment adjunct which is preferably selected from the group consisting of a surfactant system, fatty acids and/or salts thereof, enzymes, encapsulated benefit agents, soil release polymers, hueing agents, builders, chelating agents, dye transfer inhibiting agents, dispersants, enzyme stabilizers, anti-oxidants, catalytic materials, bleaching agents, bleach catalysts, bleach activators, polymeric dispersing agents, soil removal/anti-redeposition agents, polymeric grease cleaning agents, amphiphilic copolymers, brighteners, suds suppressors, dyes, hueing agents, perfume, structure elasticizing agents, fabric softeners, carriers, fillers, hydrotropes, solvents, anti-microbial agents and/or preservatives, neutralizers and/or pH adjusting agents, processing aids, rheology modifiers and/or structurants, opacifiers, pearlescent agents, pigments, anti-corrosion and/or anti-tarnishing agents, and mixtures thereof.

In one embodiment according to the present application, said composition is in the form of a liquid composition, a single-compartment pouch, a multi-compartment pouch, or a mixture thereof.

In another aspect, the present invention is related to the use of the combination of the graft copolymer according to the present application and fatty acid in inhibiting re-deposition of soil during the wash.

It is an advantage of the laundry detergent composition to provide an appropriate viscosity, especially which is desirable for consumers.

It is another advantage of the laundry detergent composition to provide an anti-gelling effect in super-compact liquid detergent composition.

DETAILED DESCRIPTION OF THE INVENTION

Definitions

As used herein, the articles including “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 “comprise” , “comprises” , “comprising” , “include” , “includes” , “including” , “contain” , “contains” , and “containing” are meant to be non-limiting, i.e., other steps and other ingredients which do not affect the end of result can be added. The above terms encompass the terms “consisting of” and “consisting essentially of” .

As used herein, when a composition is “substantially free” of a specific ingredient, it is meant that the composition comprises less than a trace amount, alternatively less than 0.1%, alternatively less than 0.01%, alternatively less than 0.001%, by weight of the composition, of the specific ingredient.

As used herein, the term “laundry detergent composition” means a composition for cleaning soiled materials, including fabrics. Such compositions may be used as a pre-laundering treatment, a post-laundering treatment, or may be added during the rinse or wash cycle of the laundering operation. The laundry detergent composition compositions may have a form selected from liquid, powder, unit dose such as single-compartment or multi-compartment unit dose, pouch, tablet, gel, paste, bar, or flake. Preferably, the laundry detergent composition is a liquid or a unit dose composition. The term of “liquid laundry detergent composition” herein refers to compositions that are in a form selected from the group consisting of pourable liquid, gel, cream, and combinations thereof. The liquid laundry detergent composition may be either aqueous or non-aqueous, and may be anisotropic, isotropic, or combinations thereof. The term of “unit dose laundry detergent composition” herein refers to a water-soluble pouch containing a certain volume of liquid wrapped with a water-soluble film.

As used herein, the term "alkyl" means a hydrocarbyl moiety which is branched or unbranched, substituted or unsubstituted. Included in the term "alkyl" is the alkyl portion of acyl groups.

As used herein, the term “washing solution” refers to the typical amount of aqueous solution used for one cycle of laundry washing, preferably from 1 L to 65 L, alternatively from 1 L to 20 L for hand washing and from 20 L to 65 L for machine washing.

As used herein, the term “soiled fabric” is used non-specifically and may refer to any type of natural or artificial fibers, including natural, artificial, and synthetic fibers, such as, but not limited to, cotton, linen, wool, polyester, nylon, silk, acrylic, and the like, as well as various blends and combinations.

Composition

The compositions of the present disclosure may be selected from the group of light duty liquid detergents compositions, heavy duty liquid detergent compositions, detergent gels commonly used for laundry, fabric enhancer compositions, and mixtures thereof.

The composition may be in any suitable form. The composition may be in the form of a liquid composition, a single-compartment pouch, a multi-compartment pouch, or a mixture thereof.

The composition can be an aqueous liquid laundry detergent composition. For such aqueous liquid laundry detergent compositions, the water content can be present at a level of from 5.0 %to 80%, e.g. 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, 60%, 70%, 80%or any ranges therebetween.

The pH range of the detergent composition is from 6.0 to 8.9, preferably from pH 7 to 8.8.

The detergent composition can also be encapsulated in a water-soluble film, to form a unit dose article. Such unit dose articles comprise a detergent composition of the present invention, wherein the detergent composition comprises less than 20%, preferably less than 15%, more preferably less than 10%by weight of water, and the detergent composition is enclosed in a water-soluble or dispersible film. Such unit-dose articles can be formed using any means known in the art. Suitable unit-dose articles can comprise one compartment, wherein the compartment comprises the liquid laundry detergent composition. Alternatively, the unit-dose articles can be multi-compartment unit-dose articles, wherein at least one compartment comprises the liquid laundry detergent composition.

Graft copolymers

The detergent composition may comprise one or more graft copolymer. The graft copolymer can be present at a level of from about 0.01%to about 15%, preferably from about 0.05%to about 10%, more preferably from about 0.1%to about 5%, and most preferably from about 0.2%to about 3%, e.g. 0.1%, 0.15%, 0.2%, 0.25%, 0.3%, 0.35%, 0.4%, 0.45%, 0.5%, 1%, 2%, or 3%, by weight of the composition.

The graft copolymer comprises: (a) polyalkylene oxide which has a number average molecular weight of from 1000 to 20,000 Daltons and is based on ethylene oxide, propylene oxide, butylene oxide or mixtures thereof, (b) N-vinylpyrrolidone, and (c) vinyl ester derived from a saturated monocarboxylic acid containing from 1 to 6 carbon atoms, wherein the weight ratio of (a) : (b) is from 1: 0.1 to 1: 2, preferably from 1: 0.3 to 1: 1, and wherein the amount, by weight, of (a) is greater than the amount of (c) .

The weight ratio of (a) : (c) is from 1.0: 0.1 to 1.0: 0.99, or from 1.0: 0.3 to 1.0: 0.9. The weight ratio of (b) : (c) can be from 1.0: 0.1 to 1.0: 5.0, or to 1.0: 4.0.

The amount, by weight of the polymer, of (a) is greater than the amount of (c) . The polymer may comprise at least 50%by weight, preferably at least 60%by weight, more preferably at least 75%by weight of (a) polyalkylene oxide.

The graft copolymer comprises and/or is obtainable by grafting (a) a polyalkylene oxide which has a number average molecular weight of from 1000 to 20000 Da, or to 15000, or to 12000 Da, or to 10000 Da and is based on ethylene oxide, propylene oxide, or butylene oxide, preferably based on ethylene oxide, with (b) N-vinylpyrrolidone, and further with (c) a vinyl ester derived from a saturated monocarboxylic acid containing from 1 to 6 carbon atoms, preferably a vinyl ester that is vinyl acetate or a derivative thereof.

Suitable polyalkylene oxides may be based on homopolymers or copolymers, with homopolymers being preferred. Suitable polyalkylene oxides may be based on homopolymers of ethylene oxide or ethylene oxide copolymers having an ethylene oxide content of from 40 mol%to 99 mol%. Suitable comonomers for such copolymers may include propylene oxide, n-butylene oxide, and/or isobutylene oxide. Suitable copolymers may include copolymers of ethylene oxide and propylene oxide, copolymers of ethylene oxide and butylene oxide, and/or copolymers of ethylene oxide, propylene oxide, and at least one butylene oxide. The copolymers may include an ethylene oxide content of from 40 to 99 mol%, a propylene oxide content of from 1.0 to 60 mol%, and a butylene oxide content of from 1.0 to 30 mol%. The graft base may be linear (straight-chain) or branched, for example a branched homopolymer and/or a branched copolymer.

Branched copolymers may be prepared by addition of ethylene oxide with or without propylene oxides and/or butylene oxides onto polyhydric low molecular weight alcohols, for example trimethylol propane, pentoses, or hexoses.

The alkylene oxide unit may be randomly distributed in the polymer or be present therein as blocks.

The polyalkylene oxides of component (a) may be the corresponding polyalkylene glycols in free form, that is, with OH end groups, or they may be capped at one or both end groups. Suitable end groups may be, for example, C1-C25-alkyl, phenyl, and C1-C14-alkylphenyl groups. The end group may be a C1-alkyl (e.g., methyl) group. Suitable materials for the graft base may include PEG 300, PEG 1000, PEG 2000, PEG 4000, PEG 6000, PEG 8000, PEG 10000, PEG 12000, and/or PEG 20000, which are polyethylene glycols, and/or MPEG 2000, MPEG 4000, MPEG 6000, MPEG 8000 and MEG 10000 which are monomethoxypolyethylene glycols that are commercially available from BASF under the tradename PLURIOL and/or block copolymers made from ethylene oxide-propylene oxide-ethylene oxide (EO-PO-EO) or from propylene oxide-ethylene oxide-propylene oxide (PO-EO-PO) such as PE 6100, PE 6800 or PE 3100 commercially available from BASF under the tradename PLURONIC.

The graft copolymers of the present disclosure may be characterized by relatively low degree of branching (i.e., degree of grafting) . In the graft copolymers of the present disclosure, the average number of grafting sites may be less than or equal to 1.0, or less than or equal to 0.8, or less than or equal to 0.6, or less than or equal to 0.5, or less than or equal to 0.4, per 50 alkylene oxide groups, e.g., ethylene oxide groups. The graft copolymers may comprise, on average, based on the reaction mixture obtained, at least 0.05, or at least 0.1, graft site per 50 alkylene oxide groups, e.g., ethylene oxide groups. The degree of branching may be determined, for example, by means of ¹³C NMR spectroscopy from the integrals of the signals of the graft sites and the -CH ₂-groups of the polyalkylene oxide.

The number of grafting sites may be adjusted by manipulating the temperature and/or the feed rate of the monomers. For example, the polymerization may be carried out in such a way that an excess of component (a) and the formed graft copolymer is constantly present in the reactor. For example, the quantitative molar ratio of component (a) and polymer to ungrafted monomer (and initiator, if any) is generally greater than or equal to 10: 1, or to 15: 1, or to 20: 1.

The polyalkylene oxides are grafted with N-vinylpyrrolidone as the monomer of component (b) . Without wishing to be bound by theory, it is believed that the presence of the N-vinylpyrrolidone ( “VP” ) monomer in the graft copolymers according to the present disclosure provides water-solubility and good film-forming properties compared to otherwise-similar polymers that do not contain the N-vinylpyrrolidone monomer. The vinyl pyrrolidone repeat unit has amphiphilic character with a polar amide group that can form a dipole, and a non-polar portion with the methylene groups in the backbone and the ring, making it hydrophobic.

The polyalkylene oxides are grafted with a vinyl ester as the monomer of component (c) . The vinyl ester may be derived from a saturated monocarboxylic acid, which may contain 1 to 6 carbon atoms, or from 1 to 3 carbon atoms, or from 1 to 2 carbon atoms, or 1 carbon atom. Suitable vinyl esters may be selected from the group consisting of vinyl formate, vinyl acetate, vinyl propionate, vinyl butyrate, vinyl valerate, vinyl iso-valerate, vinyl caproate, or mixtures thereof. Preferred monomers of component (c) include those selected from the group consisting of vinyl acetate, vinyl propionate, or mixtures thereof, preferably vinyl acetate.

Conventionally, molecular weights are expressed by their “K-values, ” which are derived from relative viscosity measurements. The graft copolymers may have a K value of from 5.0 to 200, optionally from 5.0 to 50, determined according to H. Fikentscher in 2%strength by weight solution in dimethylformamide at 25C.

The graft copolymers of the present disclosure may be characterized by a relatively narrow molar mass distribution. For example, the graft copolymers may be characterized by a polydispersity M _w/M _n of less than or equal to 3.0, or less than or equal to 2.5, or less than or equal to 2.3. The polydispersity of the graft copolymers may be from 1.5 to 2.2. The polydispersity may be determined by gel permeation chromatography using organic solvent such as hexafluoroisopropanol (HFIP) with multi-angle laser light scattering detection.

The graft copolymers may be prepared by grafting the suitable polyalkylene oxides of component (a) with the monomers of component (b) in the presence of free radical initiators and/or by the action of high-energy radiation, which may include the action of high-energy electrons. This may be done, for example, by dissolving the polyalkylene oxide in at least one monomer of group (b) , adding a polymerization initiator and polymerizing the mixture to completion. The graft polymerization may also be carried out semicontinuously by first introducing a portion, for example 10%, of the mixture of polyalkylene oxide to be polymerized, at least one monomer of group (b) and/or (c) and initiator, heating to polymerization temperature and, after the polymerization has started, adding the remainder of the mixture to be polymerized at a rate commensurate with the rate of polymerization. The graft copolymers may also be obtained by introducing the polyalkylene oxides of group (a) into a reactor, heating to the polymerization temperature, and adding at least one monomer of group (b) and/or (c) and polymerization initiator, either all at once, a little at a time, or uninterruptedly, optionally uninterruptedly, and polymerizing.

In the preparation of the graft copolymers, the order in which the monomers (b) and (c) are grafted onto component (a) may be immaterial and/or freely chooseable. For example, first N-vinylpyrrolidone may be grafted onto component (a) , and then a monomer (c) or a mixture of monomers of group (c) . It is also possible to first graft the monomers of group (c) and then N-vinylpyrrolidone onto the graft base (a) . It may be that a monomer mixture of (b) and (c) are grafted onto graft base (a) in one step. The graft copolymer may be prepared by providing graft base (a) and then first grafting N-vinylpyrrolidone and then vinyl acetate onto the graft base.

Any suitable polymerization initiator (s) may be used, which may include organic peroxides such as diacetyl peroxide, dibenzoyl peroxide, succinyl peroxide, di-tert-butyl peroxide, tert-butyl perbenzoate, tert-butyl perpivalate, tert-butyl permaleate, cumene hydroperoxide, diisopropyl peroxodicarbamate, bis (o-toluoyl) peroxide, didecanoyl peroxide, dioctanoyl peroxide, dilauroyl peroxide, tert-butyl perisobutyrate, tert-butyl peracetate, di-tert-amyl peroxide, tert-butyl peracetate, di-tert-amyl peroxide, tert-butyl hydroperoxide, mixtures thereof, redox initiators, and/or azo starters. The choice of initiator may be related to the choice of polymerization temperature.

The graft polymerization may take place at from 50℃ to 200℃, or from 70℃ to 140℃. The graft polymerization may typically be carried out under atmospheric pressure, but may also be carried out under reduced or superatmospheric pressure.

The graft polymerization may be carried out in a solvent. Suitable solvents may include: monohydric alcohols, such as ethanol, propanols, and/or butanols; polyhydric alcohols, such as ethylene glycol and/or propylene glycol; alkylene glycol ethers, such as ethylene glycol monomethyl and -ethyl ether and/or propylene glycol monomethyl and -ethyl ether; polyalkylene glycols, such as di-or tri-ethylene glycol and/or di-or tri-propylene glycol; polyalkylene glycol monoethers, such as poly (C2-C3-alkylene) glycol mono (C1-C16-alkyl) ethers having 3-20 alkylene glycol units; carboxylic esters, such as ethyl acetate and ethyl propionate; aliphatic ketones, such as acetone and/or cyclohexanone; cyclic ethers, such as tetrahydrofuran and/or dioxane; or mixtures thereof.

The graft polymerization may also be carried out in water as solvent. In such cases, the first step may be to introduce a solution which, depending on the amount of added monomers of component (b) , is more or less soluble in water. To transfer water-insoluble products that can form during the polymerization into solution, it is possible, for example, to add organic solvents, for example monohydric alcohols having 1 to 3 carbon atoms, acetone, and/or dimethylformamide. In a graft polymerization process in water, it is also possible to transfer the water-insoluble graft copolymers into a finely divided dispersion by adding customary emulsifiers or protective colloids, for example polyvinyl alcohol. The emulsifiers used may be ionic or nonionic surfactants whose HLB value is from 3.0 to 13. HLB value is determined according to the method described in the paper by W. C. Griffin in J. Soc. Cosmet. Chem. 5 (1954) , 249.

The amount of surfactant used in the graft polymerization process may be from 0.1 to 5.0 %by weight of the graft copolymer. If water is used as the solvent, solutions or dispersions of graft copolymers may be obtained. If solutions of graft copolymers are prepared in an organic solvent or in mixtures of an organic solvent and water, the amount of organic solvent or solvent mixture used per 100 parts by weight of the graft copolymer may be from 5 to 200, optionally from 10 to 100, parts by weight.

After the graft polymerization, the graft copolymer may optionally be subjected to a partial hydrolysis. In the graft copolymer, from 1.0 mol%to 60 mol%, preferably from 20 mol%to 60 mol%, more preferably from 30 mol%to 50mol%of the grafted-on monomers of component (c) are hydrolyzed. For instance, the hydrolysis of graft copolymers prepared using vinyl acetate or vinyl propionate as component (c) gives graft copolymers containing vinyl alcohol units. The hydrolysis may be carried out, for example, by adding a base, such as sodium hydroxide solution or potassium hydroxide solution, or alternatively by adding acids and if necessary, heating the mixture.

Surfactant system

The composition may comprise from 1%to 99%, preferably from 4%to 80%, e.g., 5%, 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, 60%, 70%, 80%, 90%or any ranges therebetween, by weight of the composition, of a surfactant system. Particularly, the surfactant system may comprise an anionic surfactant and a nonionic surfactant.

The anionic surfactant suitable for the composition in the present invention may be selected from the group consisting of C ₆-C ₂₀ linear alkylbenzene sulfonates (LAS) , C ₆-C ₂₀ alkyl sulfates (AS) , C ₆-C ₂₀ alkyl alkoxy sulfates (AAS) , C ₆-C ₂₀ methyl ester sulfonates (MES) , C ₆-C ₂₀ alkyl ether carboxylates (AEC) , and any combinations thereof. For example, the laundry detergent composition may contain a C ₆-C ₂₀ alkyl alkoxy sulfates (AA _xS) , wherein x is about 1-30, preferably about 1-15, more preferably about 1-10, most preferably x is about 1-3. The alkyl chain in such AA _xS can be either linear or branched, with mid-chain branched AA _xS surfactants being particularly preferred. A preferred group of AA _xS include C ₁₂-C ₁₄ alkyl alkoxy sulfates with x of about 1-3. In some embodiments, the composition comprises from 1%to 30%, preferably from 2%to 25%, more preferably from 3%to 20%, for example, 4%, 5%, 6%, 7%, 8%, 9%, 10%, 12%, 14%, 16%, 18%, 20%, or any ranges therebetween, by weight of the composition of the anionic surfactant.

The nonionic surfactant suitable for the composition in the present invention may be selected from the group consisting of alkyl alkoxylated alcohols, alkyl alkoxylated phenols, alkyl polysaccharides, polyhydroxy fatty acid amides, alkoxylated fatty acid esters, sucrose esters, sorbitan esters and alkoxylated derivatives of sorbitan esters, and any combinations thereof. Non-limiting examples of nonionic surfactants suitable for use herein include: C ₁₂-C ₁₈ alkyl ethoxylates, such as

nonionic surfactants available from Shell; C ₆-C ₁₂ alkyl phenol alkoxylates wherein the alkoxylate units are a mixture of ethyleneoxy and propyleneoxy units; C ₁₂-C ₁₈ alcohol and C ₆-C ₁₂ alkyl phenol condensates with ethylene oxide/propylene oxide block alkyl polyamine ethoxylates such as

available from BASF; C ₁₄-C ₂₂ mid-chain branched alkyl alkoxylates, BAEx, wherein x is from about 1 to about 30; alkylpolysaccharides, specifically alkylpolyglycosides; polyhydroxy fatty acid amides; and ether capped poly (oxyalkylated) alcohol surfactants. Also useful herein as nonionic surfactants are alkoxylated ester surfactants such as those having the formula R ¹C (O) O (R ₂O) nR ³ wherein R ¹ is selected from linear and branched C ₆-C ₂₂ alkyl or alkylene moieties; R ² is selected from C ₂H ₄ and C ₃H ₆ moieties and R ³ is selected from H, CH ₃, C ₂H ₅ and C ₃H ₇ moieties; and n has a value between about 1 and about 20. Such alkoxylated ester surfactants include the fatty methyl ester ethoxylates (MEE) and are well-known in the art. In some particular embodiments, the alkoxylated nonionic surfactant contained by the laundry detergent composition of the present invention is a C ₆-C ₂₀ alkoxylated alcohol, preferably C ₈-C ₁₈ alkoxylated alcohol, more preferably C ₁₀-C ₁₆ alkoxylated alcohol. The C ₆-C ₂₀ alkoxylated alcohol is preferably an alkyl alkoxylated alcohol with an average degree of alkoxylation of from about 1 to about 50, preferably from about 3 to about 30, more preferably from about 5 to about 20, even more preferably from about 5 to about 9. In some embodiments, the composition comprises from 1%to 30%, preferably from 2%to 25%, more preferably from 3%to 20%, for example, 4%, 5%, 6%, 7%, 8%, 9%, 10%, 12%, 14%, 16%, 18%, 20%, or any ranges therebetween, by weight of the composition of the nonionic surfactant.

The ratio of anionic surfactant to nonionic surfactant may be between 0.01 and 100, preferably between 0.05 and 20, e.g. 0.1, 0.2, 0.5, 0.8, 1, 2, 3, 5, 8, 10, or any ranges therebetween.

In some embodiments, the anionic surfactant comprises a C ₆-C ₂₀ linear alkylbenzene sulfonate surfactant (LAS) , preferably C ₁₀-C ₁₆ LAS, and more preferably C ₁₂-C ₁₄ LAS.

In some particular embodiments of the present invention, the anionic surfactant may be present as the main surfactant, preferably as the majority surfactant, in the composition. Preferably, the ratio of anionic surfactant to nonionic surfactant may be between 1.05 and 100, preferably between 1.1 and 20, more preferably between 1.2 and 10, and most preferably between 1.3 and 5. Particularly, the anionic surfactant may comprise C ₆-C ₂₀ linear alkylbenzene sulfonates (LAS) .

In some particular embodiments of the present invention, the nonionic surfactant may be present as the main surfactant, preferably as the majority surfactant, in the composition. Preferably, the ratio of anionic surfactant to nonionic surfactant may be between 0.01 and 0.95, preferably between 0.05 and 0.9, more preferably between 0.1 and 0.85, and most preferably between 0.2 and 0.8. Particularly, the nonionic surfactant may comprise C ₆-C ₂₀ alkoxylated alcohol.

The laundry detergent composition of the present invention may further comprise a cationic surfactant. Non-limiting examples of cationic surfactants include: quaternary ammonium surfactants, which can have up to 26 carbon atoms include: alkoxylate quaternary ammonium (AQA) surfactants; dimethyl hydroxyethyl quaternary ammonium compounds; dimethyl diisopropyl quaternary ammonium compounds; dimethyl hydroxyethyl lauryl ammonium chloride; polyamine cationic surfactants; and amino surfactants, specifically amido propyldimethyl amine (APA) .

The laundry detergent composition of the present invention may further comprise an amphoteric surfactant. Non-limiting examples of amphoteric surfactants include: amine oxides, derivatives of secondary and tertiary amines, derivatives of heterocyclic secondary and tertiary amines, or derivatives of quaternary ammonium, quaternary phosphonium or tertiary sulfonium compounds. Preferred examples include: C ₆-C ₂₀ alkyldimethyl amine oxides, betaine, including alkyl dimethyl betaine and cocodimethyl amidopropyl betaine, sulfo and hydroxy betaines, such as N-alkyl-N, N-dimethylammino-1-propane sulfonate where the alkyl group can be C ₈-C ₁₈ or C ₁₀-C ₁₄.

Other ingredients

The laundry detergent composition according to the present disclosure may further comprise from 0.01%to 10%, preferably from 0.1%to 5%, more preferably from 0.2%to 3%, most preferably from 0.3%to 2%, by weight of the composition, of a surfactant boosting polymer, preferably polyvinyl acetate grafted polyethylene oxide copolymer.

The laundry detergent composition of the present invention may further comprise a cationic surfactant. Non-limiting examples of cationic surfactants include: quaternary ammonium surfactants, which can have up to 26 carbon atoms include: alkoxylate quaternary ammonium (AQA) surfactants; dimethyl hydroxyethyl quaternary ammonium; dimethyl hydroxyethyl lauryl ammonium chloride; polyamine cationic surfactants; and amino surfactants, specifically amido propyldimethyl amine (APA) .

The laundry detergent composition herein may comprise adjunct ingredients. Suitable adjunct materials include but are not limited to: builders, chelating agents, rheology modifiers, dye transfer inhibiting agents, dispersants, 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, perfumes, perfume microcapsules, structure elasticizing agents, fabric softeners, carriers, hydrotropes, processing aids, solvents, hueing agents, structurants and/or pigments. The precise nature of these adjunct ingredients and the levels thereof in the laundry detergent composition will depend on the physical form of the composition and the nature of the cleaning operation for which it is to be used.

In some embodiments, the laundry detergent composition according to the present disclosure may further comprise from 0.01%to 10%, preferably from 0.1%to 5%, more preferably from 0.2%to 3%, most preferably from 0.3%to 2%, by weight of the composition, of a fatty acid (e.g. C _12-18 fatty acid) .

Composition Preparation

The laundry detergent composition of the present invention is generally prepared by conventional methods such as those known in the art of making laundry detergent compositions. Such methods typically involve mixing the essential and optional ingredients in any desired order to a relatively uniform state, with or without heating, cooling, application of vacuum, and the like, thereby providing laundry detergent compositions containing ingredients in the requisite concentrations.

Method of Use

Another aspect of the present invention is directed to a method of using the laundry detergent composition to treat a fabric. Such method can deliver a color protection benefit. The method comprises the step of administering from 5 g to 120 g of the above-mentioned laundry detergent composition into a laundry washing basin comprising water to form a washing solution. The washing solution in a laundry washing basin herein preferably has a volume from 1 L to 65 L, alternatively from 1 L to 20 L for hand washing and from 10 L to 65 L for machine washing. The temperatures of the laundry washing solution preferably range from 5℃ to 60℃.

In some embodiments, the composition is added to a washing machine via a dispenser (e.g. a dosing drawer) . In some other embodiments, the composition is added to an automatic dosing washing machine via an automatic dosing mechanism. In some other embodiments, the composition is added to directly a drum of a washing machine. In some other embodiments, the composition is added directly to the wash liquor.

The dosing amount in the method herein may be different depending on the washing type. In one embodiment, the method comprises administering from about 5 g to about 60 g of the laundry detergent composition into a hand washing basin (e.g., about 2-4 L) . In an alternative embodiment, the method comprises administering from about 5 g to about 100 g, preferably from about 10 g to about 65 g of the laundry detergent composition into a washing machine (e.g., about 10-45 L) .

Test Method

Test 1: Clay deposition test

Clay deposition test is conducted by using Tergotometer (Model: NE6-COP, from Copley Scientific Ltd) as below:

Clay Source: BJ clay

Clay level: 2.5 g in 0.8L city water

Water volume: 0.8L

Water type: city water

HDL Concentration: 1900 ppm

Fabric Tracer: 8cm x 8cm nil-brightener CW98 (100%Heavy Cotton, purchased from Danxin Textile Co. Beijing, China) , 2 pieces, which were pre-stripped with China National Standard powder detergent (from Taiyuan, China) in DI water by 6 times

Measure the L*ab of the fabric tracers before washing according to the clay deposition test method below.

1, Add city water

2, Add HDL and dissolve for 3 minutes.

3, Add the clay and dissolve for 3 minutes.

4, Put in fabric tracers and start stirring (main wash) .

5, The main wash time is 16 minutes.

6, Rinse twice after the main wash.

7, Remove the fabrics from the rinse container and squeeze dry.

8, Add city water, Put in fabric tracers and start stirring (rinse)

9, The rinse time is 3 minutes.

10, Repeat steps 7 and 8 again.

11, Remove the fabrics from the rinse container and natural air.

12, Measure the L*ab of the tracer washed with detergent and the clay by using IA measurement, and calculate the ΔE.

EXAMPLES

Synthesis Example 1: Synthesis of Graft Copolymer

A graft polymer which is PVP/PVAc-g-PEG at a weight ratio of 20: 30: 50 ratio with a weight average molecular weight 16, 800 Dalton was prepared as follows.

A polymerization vessel equipped with stirrer and reflux condenser was initially charged with 720g of PEG (6000 g/mol) and 60g 1, 2-propane diol (MPG) under nitrogen atmosphere. The mixture was homogenized at 70℃.

Then, 432 g of vinyl acetate (in 2 h) , 288 g of vinylpyrrolidone in 576 g of MPG (in 5 h) , and 30.2 g of tert. -butyl perpivalate in 196.6 g MPG (in 5.5 h) were metered in. Upon complete addition of the feeds, the solution was stirred at 70℃ for 1 h. Subsequently, 3.8 g tert. -butyl perpivalate in 25.0 g MPG (in 1.5 h) were metered in followed by 0.5 h of stirring.

The volatiles were removed by vacuum stripping. Then, 676.8 g deionized water were added and a steam distillation was conducted at 100℃ for 1 h.

The temperature of the reaction mixture was reduced to 80℃ and 160.6 g of aqueous sodium hydroxide solution (50 %, 40 mol%respective VAc) was added with maximum feed rate. Upon complete addition of the sodium hydroxide solution, the mixture was stirred for 1 h at 80℃and subsequently cooled to ambient temperature.

The resulting graft polymer is characterized by a K-value of 24. The solid content of the final solution is 45 %.

Example 1: Viscosity-adjusting Effect of Graft Copolymer in Laundry Detergent Composition

Eight (8) sample liquid laundry detergent compositions were prepared containing the following ingredients. Comparative Samples 1-4 do not contain a graft copolymer and Inventive Samples 1-4 contain a graft copolymer.

Table 1

1 Graft copolymer described in Synthesis Example 1 with PVP/PVAc-g-PEG at a weight ratio of 20: 30: 50 ratio with a weight average molecular weight.

Viscosity of the sample liquid laundry detergent compositions (cP under 0.5 s ^-1) were determined with TA Instruments DHR3 by employing 40mm flat steel plate with gap height 1000 μm under the temperature of 20 ℃, and shown in the following table. The results clearly indicate that the addition of the graft copolymer significantly reduces the viscosity to an appropriate value (i.e., around 1000 cP) .

Table 2

Example 2: Anti-gelling Effect of Graft Copolymer in Super-compact Liquid Detergent Composition

Four (4) sample liquid laundry detergent compositions were prepared containing the following ingredients. Comparative Samples 5 and 6 do not contain a graft copolymer and Inventive Samples 5 and 6 contain a graft copolymer.

Table 3

Viscosity (cP under 0.5 s ^-1 and 20 s ^-1) of the sample liquid laundry detergent compositions themselves, the mixture of the sample liquid laundry detergent compositions and 40%or 100%water (i.e. the ratio of laundry detergent composition to water is 1: 0.4 or 1: 1) were determined similarly as in Example 1 and shown in the following table. The mixing of the sample liquid laundry detergent compositions and water are used for simulating the scenario where the laundry detergent compositions are added into water. The results indicate that the phenomenon of “gelling” occurs when Comparative Samples 5 and 6 were mixed with water (i.e., the viscosity increases by more than 100-fold or even 1000-fold) , while the addition of the graft copolymer in Inventive Samples 5 and 6 significantly reduces the “gelling” . In other words, without the graft copolymer, the super-compact liquid detergent composition turns into gel upon touching water, while with the graft copolymer, the viscosity is sufficiently low to ensure good dissolution.

Table 4a

Table 4b

Example 3: Synergistically anti-deposition effect of Graft Copolymer and Fatty Acid in Laundry Detergent Composition

Twelve (12) sample liquid laundry detergent compositions (Samples A to L) were prepared containing the following ingredients as shown in Table 5a to 5c.

Table 5a

Table 5b

Table 5c

In accordance with Test 1: Clay deposition test as described hereinabove, the △E for these samples were measured. The higher △E indicates the worse clay deposition, while the lower △E indicates less clay deposition (i.e. stronger anti-deposition effect) .

The results shown in the Table 6a to 6c below, in which the combination of the graft copolymer and fatty acid in the context of various formula can achieve less △E compared to the composition containing the graft copolymer alone or fatty acid alone. In other words, this data indicates a synergy for anti-deposition performance between the graft copolymer and fatty acid.

Table 6a

Table 6b

Table 6c

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

Use of a graft copolymer in adjusting the viscosity of a laundry detergent composition containing the graft copolymer, wherein the graft copolymer comprising:

a) polyalkylene oxide which has a number average molecular weight of from 1000 to 20,000 Daltons and is based on ethylene oxide, propylene oxide, butylene oxide or mixture thereof;

b) N-vinylpyrrolidone; and

c) vinyl ester derived from a saturated monocarboxylic acid containing from 1 to 6 carbon atoms and/or a methyl or ethyl ester of acrylic or methacrylic acid;

wherein the weight ratio of (a) : (b) is from 1: 0.1 to 1: 2, and

wherein the amount, by weight, of (a) is greater than the amount of (c) .
The use according to Claim 1, wherein in the graft polymer

a) the polyalkylene oxide comprises and preferably consists of ethylene oxide units, and

c) the vinyl ester comprises and preferably consists of vinyl acetate.
The use according to any preceding claim, wherein in the graft polymer, the weight ratio of (a) : (c) is from 1.0: 0.1 to 1.0: 0.99, preferably from 1.0: 0.3 to 1.0: 0.9.
The use according to any one of the preceding claims, wherein in the graft polymer, from 1.0 mol%to 60 mol%, preferably from 20 mol%to 60 mol%, more preferably from 30 mol%to 50mol%of the grafted-on monomers of component (c) are hydrolyzed.
The use according to any one of the preceding claims, wherein the graft polymer has a weight average molecular weight of from 5,000 Da to 100,000 Da, preferably from 5,000 Da to 50,000 Da, more preferably from 8,000 Da to 20,000 Da.
The use according to any one of the preceding claims, wherein the composition comprises from about 0.01%to about 15%, preferably from about 0.05%to about 10%, more preferably from about 0.1%to about 5%, and most preferably from about 0.2%to about 3%, by weight of the composition, of the graft copolymer.
The use according to any one of the preceding claims, wherein the composition further comprises from about 1%to about 99%, preferably from about 5%to about 90%, more preferably from about 10%to about 85%, and most preferably from about 15%to about 80%, by weight of the composition, of a surfactant system.
A laundry detergent composition, comprising:

1) from 0.01%to 15%, by weight of the composition, a graft copolymer comprising:

a) polyalkylene oxide which has a number average molecular weight of from 1000 to 20,000 Daltons and is based on ethylene oxide, propylene oxide, butylene oxide or mixture thereof;

b) N-vinylpyrrolidone; and

c) vinyl ester derived from a saturated monocarboxylic acid containing from 1 to 6 carbon atoms and/or a methyl or ethyl ester of acrylic or methacrylic acid;

wherein the weight ratio of (a) : (b) is from 1: 0.1 to 1: 2, and

wherein the amount, by weight, of (a) is greater than the amount of (c) ; and

2) from 35%to 90%, by weight of the composition, of a surfactant system.
The laundry detergent composition according to Claim 8, wherein said surfactant system comprises C ₆-C ₂₀ linear alkylbenzene sulfonate (LAS) , C ₆-C ₂₀ alkyl sulfates (AS) , C ₆-C ₂₀ alkyl alkoxy sulfates (AAS) , C ₆-C ₂₀ methyl ester sulfonates (MES) , C ₆-C ₂₀ alkyl ether carboxylates (AEC) , a C ₆-C ₂₀ alkoxylated alcohol having a weight average degree of alkoxylation ranging from 1 to 20, a fatty acid, or any combinations thereof.
The laundry detergent composition according to Claim 8 or 9, wherein said surfactant system comprises a C ₆-C ₂₀ alkoxylated alcohol having a weight average degree of alkoxylation ranging from 1 to 20, wherein the C ₆-C ₂₀ alkoxylated alcohol is present in an amount ranging from 15%to 50%by weight of the composition.
The laundry detergent composition according to any one of Claims 8 to 10, wherein said composition comprises less than 15%of a non-aqueous solvent by weight of the composition,

preferably, wherein said non-aqueous solvent is selected from the group consisting of ethylene glycol, 1, 2-propanediol (p-diol) , 1, 3-propanediol, methylpropanediol, butanediol, glycerine, butanetriol, pentaerythritol and any combinations.
A laundry detergent composition, comprising:

1) from 0.01%to 15%, by weight of the composition, a graft copolymer comprising:

a) polyalkylene oxide which has a number average molecular weight of from 1000 to 20,000 Daltons and is based on ethylene oxide, propylene oxide, butylene oxide or mixture thereof;

b) N-vinylpyrrolidone; and

c) vinyl ester derived from a saturated monocarboxylic acid containing from 1 to 6 carbon atoms and/or a methyl or ethyl ester of acrylic or methacrylic acid;

wherein the weight ratio of (a) : (b) is from 1: 0.1 to 1: 2, and

wherein the amount, by weight, of (a) is greater than the amount of (c) ; and

2) from 20%to 90%, by weight of the composition, of a surfactant system comprising a nonionic surfactant,

wherein the nonionic surfactant is present in an amount ranging from 6.5%to 90%by weight of the composition.
The laundry detergent composition according to Claim 12, wherein the composition comprises from 20%to 75%, preferably from 20%to 60%, more preferably from 20%to 45%and most preferably 20-35%, by weight of the composition, of the surfactant system, and/or

wherein the nonionic surfactant is present in an amount ranging from 6.5%to 75%, more preferably from 6.5%to 60%, even more preferably from 6.5%to 45%and most preferably 6.5-35%by weight of the composition.
The laundry detergent composition according to Claim 12 or 13, wherein said nonionic surfactant comprises a C ₆-C ₂₀ alkoxylated alcohol having a weight average degree of alkoxylation ranging from 1 to 20, preferably from 5 to 15, more preferably from 7 to 10.
The laundry detergent composition according to Claim 12 or 13, wherein said composition comprises less than 15%, preferably less than 10%, more preferably less than 7%, most preferably less than 5%, of a non-aqueous solvent by weight of the composition,

preferably, wherein said non-aqueous solvent is selected from the group consisting of ethylene glycol, 1, 2-propanediol (p-diol) , 1, 3-propanediol, methylpropanediol, butanediol, glycerine, butanetriol, pentaerythritol and any combinations.