WO2017102402A1

WO2017102402A1 - Isotropic detergent composition comprising weight-efficient polymers

Info

Publication number: WO2017102402A1
Application number: PCT/EP2016/079732
Authority: WO
Inventors: Amalendu BANGAL; Sujitkumar Suresh HIBARE; Narayanan Subrahmaniam
Original assignee: Unilever N.V.; Unilever Plc; Conopco, Inc., D/B/A Unilever
Priority date: 2015-12-14
Filing date: 2016-12-05
Publication date: 2017-06-22

Abstract

The present invention is in the field of isotropic detergent compositions, in particular aqueous detergent compositions having more than usual amounts of polymers. It is an object of the present invention to provide stable aqueous detergent compositions comprising more than usual amounts of polymers. Disclosed is an aqueous isotropic detergent composition comprising: (i) total surfactant content of 4 to 50 % by weight; and, (ii) 5 to 15% of one or more polymeric ingredient having weight average molecular weight up to 120,000 Daltons, wherein at least 40 parts by weight of said total surfactant content is composed of alpha olefin sulphonate.

Description

ISOTROPIC DETERGENT COMPOSITION

COMPRISING WEIGHT-EFFICIENT POLYMERS

Field of the Invention

The present invention relates to isotropic detergent compositions, in particular aqueous detergent compositions having more than the usual amount of polymeric ingredients.

Background of the Invention

Liquid detergent compositions have gained consumer acceptance. Such compositions are useful for fabric cleaning and also household care applications such as dishwashing.

In addition to the surfactants and builders, which constitute a major part of such compositions, they invariably contain minor ingredients for specific benefits to the fabrics or other surfaces which are cleaned. Such ingredients include perfumes, coloured granules, enzymes, antifoam agents and shading dyes. A variety of polymers is also often included. Such polymers are usually included for anti-redeposition benefits or for soil-release benefits. Most detergent compositions contain at least two to three types of polymeric ingredients, each meant to perform an intended role. Non-limiting examples of the common polymeric ingredients include sodium carboxymethyl cellulose, acrylates, Sokalan® CP-5, polyvinyl pyrollidone and ethoxylated polyethylene imines.

Usually such polymers are present in minor quantities ranging approximately from 0.1 to 1.5 % by weight of a given detergent composition, and the amount largely depends on the intended application and the price of the product. The polymers are effective at lower levels. For this reason, they are also termed as weight-efficient ingredients.

If a formulator intends to include the usual amounts of such ingredients, there is generally no technical problem to be solved. However, if one desires to formulate a product containing more than the usual amount of an individual ingredient or to formulate a composition containing a combination of polymeric ingredients collectively adding up to more than the usual amounts, then certain formulation challenges need to be overcome. One way to do so is to include hydrotropes. A hydrotrope is a substance that improves the solubility of certain ingredients, usually surfactants, in water, particularly those systems containing high levels of builders or alkalinity. However, such an approach is not technically and economically sound because hydrotropes have no role other than the one discussed here.

Another approach is to reduce the total amount of surfactants, commonly also referred to as the Active Detergent (AD) level so as to create formulation space for additional weight-efficient ingredients. However decrease in the total surfactant content directly affects cleaning performance.

Therefore the problem to be solved is how to formulate detergent compositions with more than the usual levels of polymeric ingredients without reducing the surfactant content or without adding more hydrotropes in the compositions. WO09153184 A1 (Unilever) suggests that a laundry detergent liquid concentrate may be designed by replacing surfactant with a mixture of more weight efficient ingredients selected

from polymers and enzymes. A preferred composition uses a combination of ethoxylated polyethylene imine (EPEI) and a polyester soil release polymer (SRP) to achieve excellent oily soil and particulate detergency at significantly lower in-wash surfactant levels than would normally be delivered from a high performance liquid.

WO2004/074419 A1 (Novozyme) suggests the replacement of part of the surfactant, builder, bleach, and fillers with enzymes. It leads to significant reduction in the volume and weight of the detergent which is necessary for one wash. The drawback with the approach is that it depends on enzymes, which are expensive and are somewhat hazardous ingredients.

US5962398 B1 (Unilever) discloses isotropic liquids containing anionic polymers wherein the polymers are not hydrophobically modified but can still be incorporated into the compositions by using anionic nonionic compositions in which more than 25% of nonionic is sugar surfactant. US2002042354 A1 (Lang Frank-Peter) discloses a cleaning composition in which the cleaning performance of the soil-release polymers can be increased by the addition of a sec-alkanesulfonate and/or alpha-olefinsulfonate.

US2008/318830 A1 (Lang Frank-Peter) discloses a physically and chemically stable liquid washing and cleaning composition having dye fixatives in combination with a potential incompatible anionic surfactant in which the stability is achieved by using a surfactant system having anionic surfactant selected from linear alkylbenzenesulfonate and/or olefinsulfonate and/or alkylsulfate in combination with soap and a nonionic surfactant. We have determined that a solution to the problem discussed earlier lies in the inclusion of a certain minimum amount of alpha-olefin sulphonate in the composition as part of the total surfactant content. It is surprisingly observed that the composition provides an effective solution which allows to formulate aqueous detergent compositions containing significantly higher amount of polymeric ingredients. Such compositions may be delivered as a pourable liquid and are stable.

Summary of the Invention

Disclosed is an aqueous isotropic detergent composition, comprising:

(i) total surfactant content of 4 to 50 % by weight; and,

(ii) 5 to 15.0 % by weight of one or more polymeric ingredient having weight average molecular weight up to 120,000 Daltons, wherein at least 40 parts by weight of said total surfactant content is composed of alpha olefin sulphonate.

Detailed Description of the Invention

Isotropic liquid detergent formulations have little innate ability to suspend solid particles, for example cues and polymeric ingredients. Whilst it is possible to obtain a suspending medium by appropriate manipulation of surfactant, thickening polymers and electrolyte levels in a detergent formulation to control viscosity, such processes impose undesirable constraints on the formulation.

The present invention relates to aqueous isotropic detergent compositions comprising more than the usual levels of polymeric ingredients. Currently known isotropic detergent liquids have very low levels of performance boosting or weight efficient polymers, usually less than 1.0 % by weight and occasionally about 1.5 % by weight. However, in order to achieve enhanced technical benefits from detergent compositions, such as enhanced anti-redeposition or more/better soil release, such ingredients are required at higher than their usual levels. If a formulator intends to enter the domain of concentrated liquids with high levels of functional ingredients like surfactants, polymers or enzymes with minimal level of non-functional ingredients, then it is difficult to formulate isotropic liquids. However, it is difficult to do so on account of several factors which include instability of the resulting products. One way to do it is to include significantly high levels of hydrotropes but that will add to the cost of the raw materials. Another way is to reduce the total surfactant content in order to create formulation space for the additional polymeric ingredients.

Aqueous laundry detergent compositions contain a substantial amount of surfactants, which usually are anionic surfactants or a combination of anionic and non-ionic surfactants. The most widely used surfactants are alkyl benzene sulphonates, closely followed by ethoxylated sulphates. Anionic surfactants are ideally suited for laundry applications because they combine excellent detergency on a wide range of soils with high foaming. In the parlance of laundry detergent compositions, the total surfactant content is usually expressed as the total Active Detergent (A.D.) level. It may range anywhere from 3 % by weight to 50 % by weight of a given composition.

The aqueous detergent compositions in accordance with the invention comprises total surfactant content of 4 to 50% by weight, of which at least 20 parts by weight is alpha olefin sulphonate. In other words, the A.D. level of compositions in accordance with this invention is from 4 to 50 % by weight.

The invention disclosed herein provides detergent compositions with more than the usual levels of polymeric ingredients without reducing the total surfactant content or without increasing the amount of hydrotropes.

The compositions in accordance with the invention are aqueous isotropic detergent compositions.

The term 'aqueous' implies that the compositions are non-solid. The excluded, solid forms include detergent powders, tablets and cakes. The term also implies that the composition comprise substantial amount of water which may range from 20 % by weight to 80 % by weight of the composition. It is preferred that the compositions in accordance with the invention comprise 20 % by weight to 60 % by weight water. ln general, isotropic compositions are clear liquids wherein all the ingredients are in dissolved state. Laundry liquids generally face the problem of physical stability, especially over a prolonged period of time as surfactants and other ingredients tend to aggregate and separate out. This causes the composition to become hazy and physically unstable. Moreover, as the polymeric ingredients are also present in high concentrations, these ingredients may also separate out themselves or may affect the solubility of other ingredients. The net effect is that the compositions may not be clear to begin with or alternatively, may lose the clear and transparent nature within a few hours or days. The term isotropic is defined for the present purpose as liquid detergent compositions wherein the surfactants do not form liquid crystalline phases, like multi-lamellar droplets of surfactant material. Isotropic liquids are generally not birefringent under static conditions but may be birefringent under flow.

Total surfactant content Although there may not be need for any surfactant other than alpha olefin sulphonates, the compositions in accordance with this invention may, and preferably do, include surfactants other than alpha olefin sulphonates, which make up the remainder of the total surfactant content. Such surfactants may be anionic, non-ionic, cationic or zwitterionic surfactants or a combination of two or more types of surfactants.

The total surfactant content of compositions in accordance with the invention is 4 to

50 % by weight. It is preferred that the total surfactant content is 5 to 30 % by weight. More preferably it is 10 to 25 % by weight. The term total surfactant content denotes the total amount of surfactants present in the composition.

It is preferred that anionic surfactants other than alpha olefin sulphonate are selected from alkyl benzene sulphonates, ester sulphonates, alkyl sulfates or alkoxylated alkyl sulphates.

Anionic surfactants The alkyl or alkenyl groups of the anionic surfactants are preferably straight chain primary groups but may optionally be secondary, or branched chain groups. The expression alkoxylated refers to anionic surfactants typically containing from 1 to 20 oxyalkylene groups. For example, the sulphonated or sulphated surfactant may be sodium dodecyl benzene sulphonate, potassium hexadecyl benzene sulphonate, sodium dodecyl dimethyl benzene sulphonate, sodium lauryl sulphate, sodium tallow sulphate, potassium oleyl sulphate, ammonium lauryl monoethoxy sulphate, or monoethanolamine cetyl 10 mole ethoxylate sulphate. Other examples of suitable anionic surfactants include: sodium lauryl ether sulphate, ammonium lauryl sulphosuccinate, ammonium lauryl sulphate, ammonium lauryl ether sulphate, sodium cocoyl isethionate, sodium lauroyl isethionate, and sodium N-lauryl sarcosinate. Mostly preferably, the synthetic anionic surfactants comprise linear alkylbenzene sulphonate (LAS). It is preferred that the ethoxylated anionic surfactant is C12 alcohol ethoxy-ether sulphate (SLES).

Nonionic surfactants The total surfactant content may and preferably does include nonionic surfactants. The nonionic surfactant may be e.g. a Cioto22alkanolamide of a mono or di- lower alkanolamine, such as coconut monoethanolamide. Other preferred nonionic surfactants include ethoxylated alcohols, ethoxylated carboxylic acids, ethoxylated amines, ethoxylated alkylolamides, ethoxylated alkylphenols, ethoxylated glyceryl esters, ethoxylated sorbitan esters, ethoxylated phosphate esters, and the propoxylated or ethoxylated and propoxylated analogues of all the aforesaid ethoxylated nonionics, all having a Csto22 alkyl or alkenyl group and up to 20 ethyleneoxy and/or propyleneoxy groups, or any other nonionic surfactant which has hitherto been incorporated in powder or liquid detergent compositions e. g. amine oxides. Cationic surfactants

The total surfactant content may alternatively or in addition to anionic and non-ionic surfactants, contain cationic surfactants. Cationic surfactants include quaternary amines having two long chain (e.g., Ci2to22, especially Ci6to2o) alkyl or alkenyl groups and either two short chain (e.g., Ci to4) alkyl groups, or one short chain and one benzyl group. They also include imidazoline and quaternised imidazolines having two long chain alkyl or alkenyl groups, and amido amines and quaternised amido amines having two long chain alkyl or alkenyl groups.

Amphoteric surfactants

Compositions in accordance with the invention may contain amphoteric surfactants forming part of the total surfactant content. Amphoteric surfactants include betaines, sulphobetaines and phosphobetaines formed by reacting a suitable tertiary nitrogen compound having a long chain alkyl or alkenyl group with the appropriate reagent, such as chloroacetic acid or propane sultone.

Examples of suitable tertiary nitrogen containing compounds include: tertiary amines having one or two long chain alkyl or alkenyl groups, optionally a benzyl group and any other substituent such as a short chain alkyl group; imidazoline having one or two long chain alkyl or alkenyl groups and amidoamines having one or two long chain alkyl or alkenyl groups. Those skilled in the detergent art will appreciate that the specific surfactant types described above are only exemplary of the common surfactants suitable for use according to the invention. Any surfactant capable of performing a useful function in the wash liquor may be included. A fuller description of the principal types of surfactant which are commercially available is given in "Surface Active Agents and Detergents" by Schwartz Perry and Berch.

It is particularly preferred that in the compositions according to the invention, the total surfactant content comprises alpha-olefin sulphonate and linear alkylbenzene sulphonate in which alpha-olefin sulphonates account for 20 to 80 parts by weight of the total surfactant content. Alternatively, it is preferred that in the compositions according to the invention, the total surfactant content comprises alpha-olefin sulphonate where 20 to 80 parts by weight of the total surfactant content is composed of alpha olefin sulphonate. The balance is composed of a mixture of linear alkylbenzene sulphonate, alkyl ether sulphate and nonionic surfactant, preferably in the ratio of 4:5:1 parts by weight of the part of the total surfactant content made up by these three surfactants. For example, if 40 parts by weight of the total surfactant content is composed of alpha-olefin sulphonates, then the balance 60 parts by weight is made up alkylbenzene sulphonate, alkyl ether sulphate and nonionic surfactant in the ratio of 4:5:1 parts by weight.

Alpha-olefin sulphonate

In accordance with the invention, at least 40 parts by weight of said total surfactant content is composed of alpha olefin sulphonate (AOS). For example, in case a composition has total surfactant content of 30.0 % by weight, then at least 6.0 % by weight is alpha olefin sulphonate and the balance 24.0 % is made of other surfactants. The 6.0 % by weight AOS account for 20 parts by weight of the total surfactant content. While there is a minimum amount of AOS which needs to be present in the compositions in accordance with the invention, there is no upper limit. In other words, it is also possible that all or substantially all, e.g. 90 parts by weight or more than that, of total surfactant content is composed of alpha olefin sulphonate. It is preferred that the total surfactant content includes at least 40 parts by weight olefin sulphonate, more preferably at least 60 parts by weight alpha olefin sulphonate, still more preferably at least 80 parts by weight alpha olefin sulphonate. As disclosed earlier, it is also possible that alpha olefin sulphonates is the sole surfactant in which case all of the Active Detergent content is attributed to olefin sulphonates. The technical benefit of having more amount of the alpha olefin sulphonate is that it allows for inclusion of more and more polymeric ingredients. In other words, it is observed that the amount of polymeric ingredients that can be included in the aqueous isotropic detergent compositions is directly proportional to the amount of alpha-olefin sulphonate in the total surfactant content.

The number of carbon atoms in the alpha olefin sulfonates is preferably in the range of 8 to 18 carbon atoms, more preferably 14 or 16 to 22, e.g., a mixture of principally Cu, Ci6 and Cis, having an average of about 16 carbon atoms.

The polymeric ingredient

Compositions in accordance with the invention comprise 5 to 15.0 % by weight of one or more polymeric ingredient having weight average molecular weight up to 120,000 Daltons. Beyond this molecular weight, it may generally be difficult to include more than the usual amount of polymeric ingredients. Therefore, it is preferred that the weight average molecular weight of the one or more polymeric ingredient is in the range of 1000 to 80,000 Daltons. More preferred range is 1000 to 60,000 Daltons.

Polymers can assist in the cleaning process by helping to retail soil in solution or suspension and/or preventing the transfer of dyes. Polymers can also assist soil removal. Good weight efficiency is desirable because it enables the use of a lower amount of polymer to achieve a certain benefit such as anti-redeposition of dirt, compared with a less weight efficient polymer. They are weight-efficient, meaning that a smaller quantity of any polymer can provide the technical effects, when compared to other detergent ingredients.

In some cases, it may not be easy to include even as little as 1.0 % by weight of a polymer. An example is sodium carboxymethyl cellulose. While the number may appear small, the nature of some polymers and their inherent incompatibility with some other ingredients make it difficult to include anything more than e.g., 0.5 % by weight of such ingredients.

The composition in accordance with the present invention comprises 5 to 15% by weight of the one or more polymeric ingredient. It is preferred that the compositions in accordance with this invention comprise 5 to 12 % by weight of the one or more polymeric ingredient. It is preferred that the polymeric ingredient is at least one of a soil release polymer, an anti- redeposition polymer, a dye transfer inhibitor, a conditioning polymer or a chelating polymer.

Soil release polymer

It is preferred that the polymeric ingredient is a soil release polymer.

It is preferred that the soil release polymer is at least one of polyacrylic acid, a copolymer containing polyacrylic acid, a starch derivative, a cellulose derivative, a copolymer of polyethylene terepahalate and polyoxyethylene terephthalate or a copolymer of polyethylene terephthalate and polyethylene glycol.

Generally soil release polymers include polymers of aromatic dicarboxylic acids and alkylene glycols (including polymers containing polyalkylene glycols).

Alternatively, the polymeric soil release ingredients useful herein, and not explicitly covered earlier include those soil release agents having:

(a) one or more nonionic hydrophilic components consisting essentially of:

(i) polyoxyethylene segments with a degree of polymerization of at least 2, or

(ii) oxypropylene or polyoxypropylene segments with a degree of polymerization of from 2 to 10, wherein said hydrophile segment does not encompass any oxypropylene unit unless it is bonded to adjacent moieties at each end by ether linkages, or

(iii) a mixture of oxyalkylene units comprising oxyethylene and from 1 to about 30

oxypropylene units wherein said mixture contains a sufficient amount of oxyethylene units such that the hydrophile component has hydrophilicity great enough to increase the hydrophilicity of conventional polyester synthetic fiber surfaces upon deposit of the soil release agent on such surface, said hydrophile segments preferably comprising at least about 25% oxyethylene units and more preferably, especially for such components having about 20 to 30 oxypropylene units, at least about 50% oxyethylene units; or

(b) one or more hydrophobe components comprising: (i) C3 oxyalkylene terephthalate segments, wherein, if said hydrophobe components also comprise oxyethylene terephthalate, the ratio of oxyethylene terephthalate : C3 oxyalkylene terephthalate units is about 2:1 or lower,

(ii) C₄ to C6 alkylene or oxy C₄ to C6 alkylene segments, or mixtures therein,

(iii) poly (vinyl ester) segments, preferably polyvinyl acetate) , having a degree of

polymerization of at least 2, or (iv) Ci to C₄ alkyl ether or C₄ hydroxyalkyl ether substituents, or mixtures therein, wherein said substituents are present in the form of Ci to C₄ alkyl ether or C₄ hydroxyalkyl ether cellulose derivatives, or mixtures therein, and such cellulose derivatives are amphiphilic, whereby they have a sufficient level of Ci to C₄ alkyl ether and/or C₄ hydroxyalkyl ether units to deposit upon conventional polyester synthetic fiber surfaces and retain a sufficient level of hydroxyls, once adhered to such conventional synthetic fiber surface, to increase fiber surface hydrophilicity, or a combination of (a) and (b). Typically, the polyoxyethylene segments of (I) (i) will have a degree of polymerization of from about 200, although higher levels can be used, preferably from 3 to about 150, more preferably from 6 to about 100. Suitable oxy C₄ to C6 alkylene hydrophobe segments include, but are not limited to, end- caps of polymeric soil release agents such as M03S(CH2)_n OCH2 CH20^~ where M is sodium and n is an integer from 4 to 6.

Soil release agents characterized by poly (vinyl ester) hydrophobe segments include graft copolymers of poly (vinyl ester), e.g., Ci to C6 vinyl esters, preferably poly (vinyl acetate) grafted onto polyalkylene oxide backbones, such as polyethylene oxide backbones. Commercially available soil release agents of this kind include the SOKALAN type of material, e.g., SOKALAN HP-22, available from BASF (West Germany).

One type of preferred soil release agent is a copolymer having random blocks of ethylene terephthalate and polyethylene oxide (PEO) terephthalate. The molecular weight of this polymeric soil release agent is in the range of from about 25,000 to about 55,000 Daltons.

Another preferred polymeric soil release agent is a polyester with repeat units of ethylene terephthalate units contains 10 to 15% by weight of ethylene terephthalate units together with 90 to 80% by weight of polyoxyethylene terephthalate units, derived from a polyoxyethylene glycol of average molecular weight 300 to 5,000 Daltons. Another preferred polymeric soil release agent is a sulfonated product of a substantially linear ester oligomer comprised of an oligomeric ester backbone of terephthaloyl and oxyalkyleneoxy repeat units and terminal moieties covalently attached to the backbone. Still another preferred soil release agent is an oligomer with repeat units of terephthaloyl units, sulfoisoterephthaloyl units, oxyethyleneoxy and oxy-1 ,2- propylene units. The repeat units form the backbone of the oligomer and are preferably terminated with modified isethionate end-caps. A particularly preferred soil release agent of this type comprises about one sulfoisophthaloyl unit, 5 terephthaloyl units, oxyethyleneoxy and oxy-1 ,2- propyleneoxy units in a ratio of from about 1.7 to about 1.8, and two end-cap units of sodium 2- (2-hydroxyethoxy) - ethanesulfonate.

The most preferred soil release agents are the water soluble/miscible or dispersible polyesters such as: linear polyesters sold under the Repel-O-Tex® brand by Rhodia

(Gerol®), lightly branched polyesters sold under the Texcare® brand by Clariant, especially Texcare® SRN170, and heavily branched polyesters such as those available from Sasol and described in US 7119056.

Anti-redeposition agents:

Alternatively, the weight-efficient non surface-active polymer is an anti-redepostion polymer.

It is preferred that the anti-redeposition polymer is at least one of a copolymer of maleic and acrylic acids, an ethoxylated polyethylene imine, a copolymer of ethylene glycol and vinyl acetate or a sulphated ethoxylated hexamethylenediamine quatemised. Anti-redeposition polymers are typically polycarboxylate materials. Polycarboxylate materials, which can be prepared by polymerizing or copolymerizing suitable unsaturated monomers, are preferably admixed in their acid form. Unsaturated monomelic acids that can be polymerized to form suitable polycarboxylates include acrylic acid, maleic acid (or maleic anhydride), fumaric acid, itaconic acid, aconitic acid, mesaconic acid, citraconic acid and methylenemalonic acid. The presence in the polycarboxylates herein of monomelic segments, containing no carboxylate radicals such as vinylmethyl ether, styrene, ethylene, etc. is suitable provided that such segments do not constitute more than about 40% by weight of the polymer. Particularly suitable polycarboxylates can be derived from acrylic acid. Such acrylic acid-based polymers which are useful herein are the water- soluble salts of polymerized acrylic acid. The average molecular weight of such polymers in the acid form preferably ranges from about 2,000 to 10,000, more preferably from about 4,000 to 7,000 and most preferably from about 4,000 to 5,000. Water-soluble salts of such acrylic acid polymers can include, for example, the alkali metal, ammonium and substituted ammonium salts. Soluble polymers of this type are known materials. Acrylic/maleic-based copolymers may also be used as a preferred component of the anti- redeposition agent. Such materials include the water-soluble salts of copolymers of acrylic acid and maleic acid. The average molecular weight of such copolymers in the acid form preferably ranges from about 2,000 to 100,000 Daltons more preferably from about 5,000 to 75,000 Daltons. Polyethylene glycol (PEG) can act as a clay soil removal anti-redeposition polymer. Typical molecular weight ranges for these purposes range from about 1000 to about 100,000 Daltons. Any polymeric anti-redeposition agent known to those skilled in the art can be employed in compositions according to the invention. Polymeric anti-redeposition agents are characterized by having both hydrophilic segments, to hydrophilize the surface of hydrophobic fibres, such as polyester and nylon, and hydrophobic segments, to deposit upon hydrophobic fibres and remain adhered thereto through completion of washing and rinsing cycles and, thus, serve as an anchor for the hydrophilic segments. This can enable stains occurring subsequent to treatment with the anti-redeposition agent to be more easily cleaned in later washing procedures. The anti-redeposition agent may be selected from an anionic polymers, cationic polymers, polysaccharides, amphiphilic polymers, or nonionic polymers. Preferably the anti-redeposition polymer is an anionic polymer. Suitable examples of polysaccharides include but are not limited to sodium carboxymethylcellulose, starch derivatives and hydroxypropyl cellulose. Suitable examples of amphiphilic polymers include but are not limited to copolymers of acrylic acid and styrene or lauryl methacrylate. Suitable examples of non-ionic polymers include but are not limited to N-oxides, ethoxylated polyalkylenimines and vinylpyrrolidone-containing polymers.

Dye transfer inhibitors Further alternatively the polymer of the invention is a 'dye-transfer inhibitor¹. These prevent migration of dyes, especially during long soak times. Any suitable dye-transfer inhibitors may be used in accordance with the present invention. It is preferred that the dye transfer inhibitor is at least one of a polyvinylpyrrolidone, a polyamine N-oxide, a copolymer of N-vinylpyrrolidone and N-vinylimidazole, a polyvinyloxazolidone or a polyvinylimidazole. Nitrogen-containing, dye binding, DTI polymers are preferred. Of these polymers and co-polymers of cyclic amines such as vinyl pyrrolidone (PVP), and/or vinyl imidazole (PVI) are preferred. Polyamine N-oxide polymers suitable for use herein contain units having the following structural formula: R-AcP; wherein P is a polymerizable unit to which an N-0 group can be attached or the N- O group can form part of the polymerizable unit; A is one of the following structures: - NC(O)-, - C(0)0-, -S-, -0-, -N=; x is 0 or 1 ; and R is an aliphatic, ethoxylated aliphatic, aromatic, heterocyclic or alicyclic group or combination thereof to which the nitrogen of the N-0 group can be attached or the N-0 group is part of these groups, or the N-0 group can be attached to both units . Preferred polyamine N-oxides are those wherein R is a heterocyclic group such as pyridine, pyrrole, imidazole, pyrrolidine, piperidine and derivatives thereof. The N-0 group can be represented by the following general structures: N (O) (R') ob3, or =N (O) (R') ob i, wherein each R' independently represents an aliphatic, aromatic, heterocyclic or alicyclic group or combination thereof; and the nitrogen of the N-0 group can be attached or form part of any of the aforementioned groups. The amine oxide unit of the polyamine N-oxides has a pKa<10, preferably pKa<7, more preferably pKa< 6.

Copolymers of N-vinylpyrrolidone and N-vinylimidazole polymers (as a class, referred to as PVPVI) are also preferred. Preferably the PVPVI has an average molecular weight range from 5,000 to 1 ,000,000, more preferably from 5,000 to 100,000 Daltons. The preferred PVPVI copolymers typically have a molar ratio of N-vinylimidazole to N-vinylpyrrolidone from 1 :1 to 0.2:1 , more preferably from 0.8:1 to 0.3:1 , most preferably from 0.6:1 to 0.4:1. These copolymers can be either linear or branched. Suitable PVPVI polymers include Sokalan^™' HP56, available commercially from BASF, Ludwigshafen, Germany.

Also preferred as dye transfer inhibitors are polyvinylpyrrolidone polymers (PVP) having an average molecular weight of from about 5,000 to about 100,000 Daltons. The modified ethoxylated polyamines (EPEI) are described above and are generally linear or branched poly (>2) amines. The amines may be primary, secondary or tertiary. A single or a number of amine functions are reacted with one or more alkylene oxide groups to form a polyalkylene oxide side chain. The alkylene oxide can be a homopolymer (for example ethylene oxide) or a random or block copolymer. The terminal group of the alkylene oxide side chain can be further reacted to give an anionic character to the molecule (for example to give carboxylic acid or sulphonic acid functionality).

Preferably the composition according to the present invention comprises a dye transfer inhibitors selected from polyvinylpyrridine N-oxide (PVNO), polyvinyl pyrrolidone (PVP), polyvinyl imidazole, N-vinylpyrrolidone and N-vinylimidazole copolymers (PVPVI), copolymers thereof, and mixtures thereof.

Chelating polymers Further alternatively the polymeric ingredient is a chelating polymer.

Preferably the chelating polymer is an amino group-containing water-soluble copolymer. Preferred amino group-containing water-soluble copolymer has weight-average molecular weight in the range of from about 5000 to 100,000 Daltons. It is preferred that the chelating polymer is a

polyphosphate.

Conditioning polymers

Yet further alternatively the polymer is a conditioning polymer. It is preferred that the chelating polymer is a polyphosphonate.

One type of preferred conditioning polymer is an organic quaternary ammonium polymers selected from: (a) quaternary ammonium group-containing carbohydrate polymers, wherein the

carbohydrate comprises one or more of a glycogen derivative, a gum derivative and a chitin derivative; (b) quaternary ammonium group-containing proteinaceous polymers; or (c) quaternary ammonium group-containing synthetic polymers selected from one or more of Polyquaternium 1 to 47.

Other optional and preferred ingredients

In addition to the surfactants and the polymeric ingredient(s), the compositions in accordance with the invention may comprise other ingredients usually present in detergent compositions. These are as follows: Hydrotrope

It is preferred that the compositions in accordance with this invention comprise a hydrotrope, however, if and when present, the amount thereof is not more than 2 % by weight of the composition. Hydrotropes are solvents that is neither water nor conventional surfactants and they aid the solubilisation of the surfactants and other components in the aqueous liquid to render it isotropic. Suitable hydrotropes include MPG (monopropylene glycol), glycerol, sodium cumene sulphonate, ethanol, other glycols, e.g. di propylene glycol, diethers and urea. Water swellable clay

Suitable water swellable clays used in laundry applications are hydrous aluminium phylosilicates, sometimes with variable amounts of iron, magnesium, alkali metals, alkaline earths, and other cations. Clays form flat hexagonal sheets similar to the micas. Clays are ultrafine-grained (normally considered to be less than 2 micrometres in size on standard particle size classifications).

The Smectite group includes dioctahedral smectites such as montmorillonite and nontronite and trioctahedral smectites for example saponite, as well as bentonite, pyrophylite, hectorite, sauconite, talc, beidellite. Other 2:1 clay types include sepiolite or attapulgite, clays with long water channels internal to their structure. Phylosilicates include: Halloysite, Kaolinite, lllite, Montmorillonite, Vermiculite, Talc, Palygorskite, Pyrophylite. Montmorillonite is a smectite phylosilicate

(Na,Ca)o.33(AI,Mg)2(Si₄Oi o)(OH)2^>>nH20. Montmorillonite is a very soft phylosilicate group of minerals that typically form in microscopic crystals to form a clay. Montmorillonite, is a 2:1 clay, meaning that it has 2 tetrahedral sheets sandwiching a central octahedral sheet. The particles are plate-shaped with an average diameter of approximately one micrometre. Montmorillonite is the main constituent of bentonite - a volcanic ash weathering product. Hectorite is a natural smectite clay with high silica content. Natural hectorite is a rare soft, greasy, white clay mineral.

Suitable water-swellable clays include: smectites, kaolins, ilites, chlorites and attapulgites. Specific examples of such clays include bentonite, pyrophylite, hectorite, saponite, sauconite, nontronite, talc and beidellite as smectite type clays. The water- swellable clay is preferably a smectite-type clay. Briqhteners

Any optical brighteners or other brightening or whitening agents known in the art may be incorporated at levels typically from about 0.05 percent to about 1.2 percent, by weight, into the liquid detergent formulations.

Commercial optical brighteners, which may be useful in the present invention, may be classified into subgroups, which include, but are not necessarily limited to: derivatives of stilbene, pyrazoline, cournarin, carboxylic acid, methinecyanines, dibenzothiphene-5,5- dioxide, azoles, 5- and 6- membered- ring heterocycles, and other miscellaneous agents. Examples of such brighteners are disclosed in "The Production and Application of Fluorescent Brightening Agents", M. Zahradnik, Published by John Wiley and Sons, New York (1982). Dye Transfer Inhibiting Agents.

Bleaches

Optionally, the compositions according to the present invention may contain a bleach or bleach system. This bleach or bleach system may be, for example: (a) a peroxygen bleach species alone and/or in combination with a bleach activator and/or a transition metal catalyst; and (b) a transition metal catalysts in a formulation substantially devoid of peroxygen species. Bleaching catalysts for stain removal have been developed over recent years and may be used in the process of the present invention. Examples of transition metal bleaching catalysts that may be used are found, for example, in:

Builders and Sequestrants

Compositions in accordance with the invention may also optionally contain relatively low levels of organic detergent builder or sequestrants. Examples include the alkali metal, citrates, succinates, malonates, carboxymethyl succinates,

carboxylates, polycarboxylates and polyacetyl carboxylates. Specific examples include sodium, potassium and lithium salts of oxydisuccinic acid, mellitic acid, benzene polycarboxylic acids, and citric acid.

If utilized, the organic builder materials may comprise from about 0.5% to 20 wt%, preferably from 1 wt% to 10 wt%, of the composition. The preferred builder level is less than 10 wt% and preferably less than 5 wt% of the composition. A preferred sequestrant is HEDP (1 -Hydroxyethylidene -1 , 1 ,- diphosphonic acid), for example sold as Dequest 2010. Also suitable but less preferred as it gives inferior cleaning results is Dequest® 2066 (Diethylenetriamine penta(methylene phosphonic acid or Heptasodium DTP MP). Buffers

Compositions in accordance with the invention may also optionally contain buffers. In addition to the 1 % TEA the presence of buffer is preferred for pH control; preferred buffers are MEA, and TEA. Visual cues

The compositions may comprise visual cues made of solid materials insoluble the composition. Preferably they are used in combination with an external structurant to ensure that they remain in suspension.

Viscosity and other properties

It is preferred that viscosity of the compositions in accordance with this invention is in the range of 50 to 2000 cP, more preferably 100 to 2000 cP. The viscosity is measured at a shear rate of 20 s^"1 at 25 °C.

It is preferred that pH of the composition of the present invention (undiluted) is in the range of 2 to 7, more preferably 2 to 5 and most preferably 2 to 4. Product Form

The aqueous isotropic detergent compositions of the present invention a physical form, which is pourable liquid. The liquids may be further thickened by addition of conventional thickeners.

Packaging

The formulations may be packaged in any form of container. Typically a plastic bottle with a detachable closure/pouring spout. The bottle may be rigid or defoimable. A defoimable bottle allows the bottle to be squeezed to aid dispensing. If clear bottles are used they may be formed from PET. Polyethylene or clarified polypropylene may be used. Preferably the container is clear enough that the liquid, with any visual cues therein, is visible from the outside. The bottle may be provided with one or more labels, or with a shrink wrap sleeve which is desirably at least partially transparent, for example 50 percent of the area of the sleeve may be transparent. The adhesive used for any transparent label should not adversely affect the transparency.

Method of use

Following the teaching in WO2009/153184 A1 the liquids according to the invention are intended to be formulated to allow them to be dosed to a typical front loading automatic washing machine at a dosage level of 20 ml_. However, the invention is also suitable for the more conventional dosage levels of about 35 ml_, to obtain suitable liquids of this type all that is necessary is to add further water and possibly perfume to the 20 mL type of liquid. The weight efficient non-surface-active polymer claimed are also stable in these more dilute compositions.

The invention will now be described with reference to the following non-limiting examples. Examples Example 1 : Effect of AOS on the inclusion of acrylate polymer

Compositions as given in table 1 were prepared by mixing the given amounts of ingredients. In general the compositions were kept as simple as possible by including only the surfactants mentioned as total surfactant content in column 1 , the amount of polymer mentioned in column 3 and the balance was water. Viscosity of each composition was measured as described earlier.

The following test was performed in order to ascertain whether the compositions were stable or not.

100 ml of each composition was taken in a Tarson® tube. These samples were then stored under standard laboratory conditions where the temperature during the day was maintained in the range of 23 to 25 °C. The samples were observed after 72 hours for any visible signs of phase separation, or in other words whether they were isotropic or not. Table 1

Note: In table 1

• AOS means Alpha olefin sulphonate

• SLES means Sodium lauryl ether sulphate

• LAS means Sodium salt of linear alkyl benzene sulphonates

• Nl means non-ionic surfactant, C12 fatty alcohol having 3 moles of ethoxylation

• Pbw means 'parts by weight'

• Weight average molecular weight of the polymer was 60,000 Daltons.

The data in the table 1 shows how the amount of AOS positively affects the formulation's ability to assimilate/stabilise more and more amount of polymeric ingredient. This effect is achieved by keeping the total surfactant content constant at 21 % by weight. The effect of AOS is clear even at 20 parts by weight AOS. As the amount of AOS is from 20 to 40 parts by weight and beyond, the formulation allows introduction of more and more polymeric ingredient, whilst still being stable after 72 hours. It is generally believed that if a formulation is stable for 72 hours it is very likely to remain stable for an extended period. A full AOS-containing formulation (100 parts by weight AOS) allows for inclusion of as much 11 % by weight of the polymer in the case of Composition 1.

Composition 2 contained AOS making up from 20 to 80 parts by weight of the total surfactant content. The remainder of the surfactant content was composed of three other surfactants, LAS, SLES and non-ionic surfactants with their respective amounts in the remainder of the total surfactant content, also mentioned in the table. In this case also the observation is identical to that of Composition 1.

The observations pertaining to Composition 3 are similar to that for Composition 1.

Example 2: Effect of AOS on the inclusion of cellulosic polymer

Compositions as given in table 2 were prepared. The viscosity of each composition was measured as described earlier. Stability tests were performed as described earlier.

The data is summarised in table 2.

Table 2

Table 2 confirms the observations shown in table 1. The results indicate how AOS facilitates the inclusion of SCMC in the compositions. SCMC is a particularly difficult polymer as far as its inclusion in liquid detergents is concerned. It is usually dosed at about 0.5 % by weight but the present invention allows inclusion of upto 5.0 % by weight without compromising on the stability.

Claims

1. An aqueous isotropic detergent composition comprising:

(i) total surfactant content of 4 to 50 % by weight; and,

2. A composition as claimed in claim 1 wherein balance of said total surfactant content

comprises anionic surfactants other than alpha olefin sulphonate, or cationic surfactants or zwitterionic surfactants or non-ionic surfactants or a combination thereof.

3. A composition as claimed in claim 2 wherein said anionic surfactants other than alpha olefin sulphonate are selected from alkyi benzene sulphonates, ester sulphonates, alkyi sulfates or alkoxylated alkyi sulphates.

4. A composition as claimed in any one of the preceding claims 1 to 3 wherein the polymeric ingredient is at least one of a soil release polymer, an anti-redeposition polymer, a dye transfer inhibitor, a conditioning polymer or a chelating polymer.

5. A composition as claimed in claim 4 wherein said soil release polymer is at least one of polyacrylic acid, a copolymer containing polyacrylic acid, a starch derivative, a cellulose derivative, a copolymer of polyethylene terephthalate and polyoxyethylene terephthalate or a copolymer of polyethylene terephthalate and polyethylene glycol.

6. A composition as claimed in claim 4 wherein the anti-redeposition polymer is at least one of a copolymer of maleic acid and acrylic acid, an ethoxylated polyethylene imine, a copolymer of ethylene glycol and vinyl acetate or a sulphated ethoxylated hexamethylenediamine quatemised.

7. A composition as claimed in claim 4 wherein the dye transfer inhibitor is at least one of a polyvinylpyrrolidone, a polyamine N-oxide, a copolymer of N-vinylpyrrolidone and N- vinylimidazole, a polyvinyloxazolidone or a polyvinylimidazole.

8. A composition as claimed in claim 4 wherein the chelating polymer is a polyphosphonate.

9. A composition as claimed in any one of the preceding claims 1 to 8, wherein the amount of hydrotrope in said composition is not more than 2 % by weight.