WO2023099595A1

WO2023099595A1 - Fabric softening composition

Info

Publication number: WO2023099595A1
Application number: PCT/EP2022/083910
Authority: WO
Inventors: Christopher Boardman; Louise Stephanie CONNELL-FIELDING; Martin Charles Crossman
Original assignee: Unilever Ip Holdings B.V.; Unilever Global Ip Limited; Conopco, Inc., D/B/A Unilever
Priority date: 2021-12-02
Filing date: 2022-11-30
Publication date: 2023-06-08

Abstract

A fabric softening composition comprising: a) Natural oil; b) Film forming polymer; and c) 0 to 4 wt.% anionic and/or cationic surfactant.

Description

FABRIC SOFTENING COMPOSITION

Field of the Invention

The present invention is in the field of fabric softening compositions.

Background of the Invention

Fabric softening is traditionally delivered by quaternary ammonium compounds. However, there is a desire for alternative softening compositions which deliver improved softening during the laundry process.

Summary of the Invention

It has been found that fabric softening compositions comprising a natural oil and a film forming polymer demonstrate improved softening; the natural oil and film forming polymer provide a synergistic softening effect. Equally by delivering the ingredients in a low surfactant composition, improved softening is also provided.

According in one aspect of the present invention is provided a fabric softening composition comprising: a. Natural oil; b. Film forming polymer; c. 0 to 4 wt.% anionic and/or cationic surfactant.

The invention further relates to a method of delivering softening to fabrics, wherein a composition as described herein is added in the wash or rinse stage of the laundry process.

The invention additionally relates to use of the fabric softening compositions as described herein to soften fabrics. Detailed Description of the Invention

These and other aspects, features and advantages will become apparent to those of ordinary skill in the art from a reading of the following detailed description and the appended claims. For the avoidance of doubt, any feature of one aspect of the present invention may be utilised in any other aspect of the invention. The word “comprising” is intended to mean “including” but not necessarily “consisting of” or “composed of.” In other words, the listed steps or options need not be exhaustive. It is noted that the examples given in the description below are intended to clarify the invention and are not intended to limit the invention to those examples per se.

Similarly, all percentages are weight/weight percentages unless otherwise indicated. Except in the operating and comparative examples, or where otherwise explicitly indicated, all numbers in this description indicating amounts of material or conditions of reaction, physical properties of materials and/or use are to be understood as modified by the word “about”. Numerical ranges expressed in the format "from x to y" are understood to include x and y. When for a specific feature multiple preferred ranges are described in the format "from x to y", it is understood that all ranges combining the different endpoints are also contemplated.

Fabric softening compositions

The fabric softening compositions of the present invention may be used to replace traditional fabric conditioner compositions or may be used in addition to a traditional fabric conditioner composition, i.e. , the compositions may be used by the consumer to supplement the benefits delivered by their traditional fabric conditioner.

Natural oil

The compositions of the present invention comprise natural oils. Natural oils comprise plant oils and/or the esterified fatty acids of plant oils. Natural oils exclude mineral oils derived from petroleum. Preferably the natural oil is a liquid or soft solid.

Plant oils include vegetable (e.g., olive oil), nut and seed oils. Plant oils also include microbial oils, which are oils produced by microbes or other organisms, including algal oils and including genetically modified or engineered microbes that produce oils. Plant oils preferably include triglycerides, free fatty acids, or a combination of both. Preferably the natural oil comprises seed oils or the esterified fatty acids thereof. Seed oils include almond, argan, babassu, borage, camelina, canola ®, castor, chia, cherry, coconut, corn, cotton, coffee, Cuphea Viscosissima, flax (linseed), grape, hemp, hepar, jatropha, jojoba, Lesquerella Fendleri oil, Moringa Oleifera oil, macadamia, mango, mustard, neem, oil palm, perilla, rapeseed, safflower, sesame, shea, stillingia, soybean, sunflower, tonka bean, tung. The natural oil may comprise a triglyceride or mixtures of triglycerides with varying degrees of alkyl chain length and unsaturation. Each triglyceride comprises one or two or more, preferably three fatty acids, bonded by a glycerol bridge.

Preferably the natural oil comprises an ester oil. Ester oils are the esterified fatty acids of any of the above oils. The glycerides (of the above oils) are first hydrolysed to release fatty acids from the glycerol moiety, and then the fatty acids are then reacted with alcohols (mono-, di-, tri-, tetra, etc.,) to form an ester oil. Preferably the natural oil comprises esterified fatty acids of seed oils.

Preferably, the ester oil is a polyol ester (i.e. , more than one alcohol group is reacted to form the polyol ester). Preferably the polyol ester is formed by esterification of a polyol (i.e., reacting a molecule comprising more than one alcohol group with acids). Preferably the polyol ester comprises at least two ester linkages. Preferably the polyol ester comprises no hydroxyl groups.

Preferably the ester oil is a pentaerythritol e.g., a pentaerythritol tetraisostearate. Exemplary structures of the compound are (I) and (II) below:

Preferably the ester oil is saturated.

Preferably, the ester oils are esters containing straight or branched, saturated or unsaturated carboxylic acids.

Suitable ester oils are the fatty ester of a mono or polyhydric alcohol having from 1 to about 24 carbon atoms in the hydrocarbon chain and mono or polycarboxylic acids having from 1 to about 24 carbon atoms in the hydrocarbon chain with the proviso that the total number of carbon atoms in the ester oil is equal to or greater than 16 and that at least one of the hydrocarbon radicals in the ester oil has 12 or more carbon atoms.

Preferably the viscosity of the natural oil is from 2 mPa. s to 400 mPa. s at a temperature of 25 C, more preferably a viscosity from 2 to 150 mPa. s, most preferably a viscosity from 10 to 100 mPa.s.

Preferably the refractive index of the natural oil is from 1.445 to 1.490, more preferred from 1.460 to 1.485.

The natural oil may be characterized by the percentage modern carbon in the oil. The percentage modern carbon (pMC) level is based on measuring the level of radiocarbon (C14) which is generated in the upper atmosphere from where it diffuses, providing a general background level in the air. The background level in the air represents 100% modern carbon. The level of C14, once captured (e.g. by biomass) decreases over time, in such a way that the amount of C14 is essentially depleted after 45,000 years. Hence the C14 level of fossil-based carbons, as used in the conventional petrochemical industry is virtually zero.

A pMC value of 100% would indicate that 100% of the carbon came from plants or animal byproducts (biomass) living in the natural environment (or as captured from the air) and a value of 0% would mean that all of the carbon was derived from petrochemicals, coal and other fossil sources. A value between 0-100% would indicate a mixture. The higher the value, the greater the proportion of naturally sourced components in the oil.

The pMC level can be determined using the % Biobased Carbon Content ASTM D6866-20 Method B, using a National Institute of Standards and Technology (NIST) modern reference standard (SRM 4990C). Such measurements are known in the art are performed commercially, such as by Beta Analytic Inc. (USA). The technique to measure the C14 carbon level is known since decades and most known from carbon-dating archaeological organic findings.

Natural oils preferably comprise 50 to 100 percent modern carbon, more preferably 80 to 100 percent modern carbon and most preferably 95 to 100 percent modern carbon.

The natural oil of the current invention may be in the form of a free oil or an emulsion.

The natural oil may be encapsulated. Suitable encapsulating materials, may comprise, but are not limited to; aminoplasts, proteins, polyurethanes, polyacrylates, polymethacrylates, polysaccharides, polyamides, polyolefins, gums, silicones, lipids, modified cellulose, polyphosphate, polystyrene, polyesters or combinations thereof. Particularly preferred materials are aminoplast microcapsules, such as melamine formaldehyde or urea formaldehyde microcapsules. Suitable microcapsules are disclosed in US 2003215417.

In one aspect of the present invention, the microcapsules shell maybe coated with polymer to enhance the ability of the microcapsule to adhere to fabric, as described in U.S. Patent Nos. 7,125,835; 7,196,049; and 7,119,057

The compositions described herein preferably comprise amount 0.1 wt. % to 15 wt.% natural oil, by weight of the composition, preferably 0.25 to 10 wt.%, more preferably 0.5 to 7 wt.% and most preferably 0.5 to 5 wt.% natural oil.

Film forming polymer

The compositions of the present invention comprise film forming polymers. The term film forming polymer is well known in the art and refers to polymers which deposit on the surface of a fabric and provide a so-called film on the surface of the fabric. The film-forming polymers may be selected from synthetic organic polymers, natural polymers, modified natural polymers and combinations thereof.

Examples of suitable film forming polymers include: polyvinyl alcohol; polyvinyl pyrroiidone; polyethylene glycols; polyvinylpyrrolidones; polyesters including copolyesters; polyurethanes; vinylpyrrolidone I vinyl ester copolymers; modified proteins such as hydrolysed proteins from animals, such as collagen, keratin and milk or from plants, such as wheat, corn, rice, potatoes, soybeans or almonds, from marine life forms, such as collagen, fish or algae or biotechnology- derived protein and derivatives of hydrolysed proteins; and combinations thereof.

The film forming polymer preferably has a weight-average molecular weight Mw in the range from 300 g I mol to 5,000,000 g I mol, preferably from 300 g I mol to 3,000,000 g I mol and more preferably from 500 g I mol to 2,000,000 g I mol. The average molecular weight Mw can be determined, for example, by gel permeation chromatography (GPC) (Andrews P., "Estimation of the Molecular Weight of Proteins by Sephadex Gel Filtration"; Biochem J., 1964, 91, pages 222 to 233). The use of protein hydrolysates with average molecular weights in this range leads to a particularly effective perfume benefits.

Preferred film forming polymers are selected from polymers comprising: polyvinyl alcohol; polyvinyl pyrrolidone; polyethylene glycol; polyethylene oxide; polyesters including copolyesters; hydrolysed proteins and derivatives thereof or any combinations thereof. More preferably the film forming polymer is selected from polymers comprising: hydrolysed proteins or polyesters, including co-polyesters; and combinations thereof.

Protein hydrolysates for use in the present invention are proteins which are obtainable by hydrolysis of proteins. Hydrolysis can be achieved by chemical reactions, in particular by alkaline hydrolysis, acid hydrolysis, enzymatic hydrolysis or combinations thereof. For alkaline or acid hydrolysis, methods such as prolonged boiling in a strong acid or strong base may be employed. For enzymatic hydrolysis, all hydrolytic enzymes are suitable, for example alkaline proteases. The production of protein hydrolysates is described, for example, by G. Schuster and A. Domsch in soaps and oils Fette Wachse 108, (1982) 177 and Cosm.Toil, respectively. 99, (1984) 63, by H.W. Steisslinger in Parf.Kosm. 72, (1991) 556 and F. Aurich et al. in Tens. Surf. Det. 29, (1992) 389 appeared.

The hydrolysed proteins of the present invention may come from a variety of sources. The proteins may be naturally sourced, e.g., from plants or animal sources, or they may be synthetic proteins. Preferably the protein is a naturally sourced protein or a synthetic equivalent of a naturally sourced protein. A preferred class of proteins are plant proteins, i.e. , proteins obtained from a plant or synthetic equivalents thereof. Preferably the protein is obtained from a plant. Preferred plant sources include nuts, seeds, beans, and grains. Particularly preferred plant sources are grains. Examples of grains include cereal grains (e.g., millet, maize, barley, oats, rice and wheat), pseudocereal grains (e.g., buckwheat and quinoa), pulses (e.g., chickpeas, lentils and soybeans) and oilseeds (e.g. mustard, rapeseed, sunflower seed, hemp seed, poppy seed, flax seed). Most preferred are cereal grains, in particular wheat proteins or synthetic equivalents to wheat proteins.

It is preferred that the protein hydrolysate is cationically modified. Preferably, a cationically modified wheat protein hydrolysate. Preferably the hydrolyses protein is a quaternised protein. Preferably the hydrolysed protein contains at least one radical of the formula:

R1-N⁺(CH³)₂-CH₂-CH(OH)-CH₂ -XR

R1 is an alkyl group having 1 to 30 carbon atoms, an alkenyl group having 1 to 30 carbon atoms, or a hydroxyalkyl group having 1 to 30 carbon atoms. R1 is preferably selected from, a methyl group, a C 10-18 alkyl, or a C 10-13 alkenyl group, X is O, N or S

R represents the protein residue. The term "protein residue" is to be understood as meaning the backbone of the corresponding protein hydrolyzate formed by the linking of amino acids, to which the cationic group is bound.

The cationization of the protein hydrolysates with the above-described residues can be achieved by reacting the protein hydrolyzates, in particular the reactive groups of the amino acids of the protein hydrolysates, with halides which otherwise correspond to compounds of the above formula (wherein the X-R moiety is replaced by a halogen).

The hydrolysed protein may a be hydrolysed protein-silicone copolymer. The silicone component may be covalently bonded to amino groups of the protein groups. Silicone components may form cross-links between different protein chains. The protein component of a protein-silicone copolymer may represent from 5 to 98% by weight of the copolymer, more preferably from 50 to 90%.

Preferably, the silicone component is organofunctional silane/silicone compounds. The protein- silicone copolymer may be prepared by covalently attaching organofunctional silane/silicone compounds to the protein amino groups to form larger polymer molecules including protein cross-linking. In addition, further polymerisation may occur through condensation of silanol groups, and such further polymerisation increases the amount of cross-linking. The organofunctional silicone compounds used for reaction with the protein component to form the copolymer must contain a functional group capable of reacting with the chain terminal and/or side chain amino groups of the protein. Suitable reactive groups include, for example, acyl halide, sulphonyl halide, anhydride, aldehyde and epoxide groups. The silicone component may be any compound which contains a siloxane group (Si-O-Si) or any silane capable of forming a siloxane in situ by condensation of silanol (Si-OH) groups or any alkoxysilane or halosilane which hydrolyses to form a corresponding silanol and then condenses to form a siloxane group.

Wheat protein hydrolysates are commercially available, for example, from Croda under the trade name ColtideRadiance.

Polyester polymers for use in the invention may include a variety of charged (e.g., anionic) as well as non-charged monomer units and structures may be linear, branched or star shaped. The polyester structure may also include capping groups to control molecular weight or to alter polymer properties such as surface activity.

Polyesters for use in the invention may suitably be selected from copolyesters of dicarboxylic acids (for example adipic acid, phthalic acid or terephthalic acid), diols (for example ethylene glycol or propylene glycol) and polydiols (for example polyethylene glycol or polypropylene glycol). The copolyester may also include monomeric units substituted with anionic groups, such as for example sulfonated isophthaloyl units. Examples of such materials include oligomeric esters produced by transesterification/oligomerization of poly(ethyleneglycol) methyl ether, dimethyl terephthalate (“DMT”), propylene glycol (“PG”) and poly(ethyleneglycol) (“PEG”); partly- and fully-anionic-end-capped oligomeric esters such as oligomers from ethylene glycol (“EG”), PG, DMT and Na-3,6-dioxa-8-hydroxyoctanesulfonate; nonionic-capped block polyester oligomeric compounds such as those produced from DMT, Me-capped PEG and EG and/or PG, or a combination of DMT, EG and/or PG, Me-capped PEG and Na-dimethyl-5-sulfoisophthalate, and copolymeric blocks of ethylene terephthalate or propylene terephthalate with polyethylene oxide or polypropylene oxide terephthalate. Suitable polyesters can be obtained from Clariant under the trade name Texcare®.

Preferred polyesters for use in the invention include copolyesters formed by condensation of terephthalic acid ester and diol, preferably 1 ,2 propanediol, and further comprising an end cap formed from repeat units of alkylene oxide capped with an alkyl group. Examples of such materials have a structure corresponding to general formula (III):

in which R¹ and R² independently of one another are X-(OC2H4)n-(OC3H6)_{m ;} in which X is CM alkyl and preferably methyl; n is a number from 12 to 120, preferably from 40 to 50; m is a number from 1 to 10, preferably from 1 to 7; and a is a number from 4 to 9.

Because they are averages, m, n and a are not necessarily whole numbers for the polymer in bulk.

Mixtures of any of the above described materials may also be used.

The compositions described herein preferably comprise 0.005 to 10 wt.% film forming polymer, by weight of the composition, more preferably 0.01 to 5 wt.%, even more preferably 0.02 to 4 wt.% and most preferably 0.05 to 3 wt.%.

Film forming polymers can have a negative effect on the softening delivered from a fabric conditioner composition. However, it has been found that in the presence of a natural oil softening is improved and a synergistic effect is provided.

Anionic and Cationic surfactants

The compositions of the present invention comprise low levels or most preferably no anionic or cationic surfactant.

The compositions comprise 0 to 4 wt.% anionic and/or cationic surfactant, preferably 0 to 2 wt.% anionic and/or cationic surfactant, more preferably, 0 to 1 wt.% anionic and/or cationic surfactant, even more preferably 0 to 0.85 wt. % and most preferably 0 to 0.5 wt. % anionic and/or cationic surfactant. The composition can be completely free of anionic and cationic surfactant.

By ‘0 to 4 wt.% anionic and/or cationic surfactant’ it is intended that the composition can contain a maximum level of 4 wt. % combined anionic and cationic surfactant, or in other words; if only cationic surfactant is present, 0 to 4 wt.% cationic surfactant, or if only anionic surfactant is present, 0 to 4 wt.% anionic surfactant or if both anionic and cationic surfactant are present a combined amount of 0 to 4 wt. % anionic and cationic surfactant.

The softening benefit provided by the compositions described herein is enhanced by the low levels of anionic and cationic surfactants in the compositions.

Non-ionic surfactants

The fabric softening composition may preferably comprise non-ionic surfactant. Preferably the composition comprises 0.5 to 15 wt.% non-ionic surfactant, more preferably 0.5 to 10 wt.% non- ionic surfactant, most preferably 0.5 to 8 wt.% non-ionic surfactant. The correct amount of non- ionic surfactant is important to achieve the desired delivery of the perfume. The compositions may require sufficient non-ionic surfactant to carry the benefit agent, however too much non- ionic surfactant will interfere with the action of the laundry liquid or powder with which it is used and will prevent release of the perfume due to insufficient dilution.

The non-ionic surfactants will preferably have an HLB value of 12 to 20, more preferably 14 to 18.

Examples of non-ionic surfactant materials include: ethoxylated materials, polyols such as polyhydric alcohols and polyol esters, alkyl polyglucosides, EO-PO block copolymers (Poloxamers). Preferably, the non-ionic surfactant is selected from ethoxylated materials. Preferred ethoxylated materials include: fatty acid ethoxylates, fatty amine ethoxylates, fatty alcohol ethoxylates, nonylphenol ethoxylates, alkyl phenol ethoxylate, amide ethoxylates, Sorbitan(ol) ester ethoxylates, glyceride ethoxylates (castor oil or hydrogenated castor oil ethoxylates) and mixtures thereof.

More preferably, the non-ionic surfactant is selected from ethoxylated surfactants having a general formula: R¹O(R²O)_XH

R¹ = hydrophobic moiety.

R² = C2H4 or mixture of C2H4 and C3H6 units x = 4 to 120

R¹ preferably comprises 8 to 25 carbon atoms and mixtures thereof, more preferably 10 to 20 carbon atoms and mixtures thereof most preferably 12 to 18 carbon atoms and mixtures thereof. Preferably, R is selected from the group consisting of primary, secondary and branched chain saturated and/or unsaturated hydrocarbon groups comprising an alcohol, carboxy or phenolic group. Preferably R is a natural or synthetic alcohol.

R² preferably comprises at least 50% C2H4, more preferably 75% C2H4, most preferably R² is C2H4.

X is preferably 8 to 90 and most preferably 10 to 60.

Examples of commercially available, suitable non-ionic surfactants include: Genapol C200 ex. Clariant and Eumulgin CO40 ex. BASF.

Perfume

The compositions of the present invention preferably comprise perfume i.e., free oil perfume or non-confined perfumes. The compositions my preferably also comprise perfume microcapsules. The compositions of the present invention may comprise one or more perfume compositions. The perfume compositions may be in the form of a mixture of free perfume compositions or a mixture of encapsulated and free oil perfume compositions.

Preferably the compositions of the present invention comprise 0.5 to 20 wt.% perfume ingredients, more preferably 1 to 15 wt.% perfume ingredients, most preferably 2 to 10 wt. % perfume ingredients. By perfume ingredients it is meant the combined free perfume and any encapsulated perfume.

Useful perfume components may include materials of both natural and synthetic origin. They include single compounds and mixtures. Specific examples of such components may be found in the current literature, e.g., in Fenaroli's Handbook of Flavor Ingredients, 1975, CRC Press; Synthetic Food Adjuncts, 1947 by M. B. Jacobs, edited by Van Nostrand; or Perfume and Flavor Chemicals by S. Arctander 1969, Montclair, N.J. (USA). These substances are well known to the person skilled in the art of perfuming, flavouring, and/or aromatizing consumer products.

Particularly preferred perfume components are blooming perfume components and substantive perfume components. Blooming perfume components are defined by a boiling point less than 250°C and a LogP greater than 2.5. Substantive perfume components are defined by a boiling point greater than 250°C and a LogP greater than 2.5. Preferably a perfume composition will comprise a mixture of blooming and substantive perfume components. The perfume composition may comprise other perfume components.

It is commonplace for a plurality of perfume components to be present in a free oil perfume composition. In the compositions for use in the present invention it is envisaged that there will be three or more, preferably four or more, more preferably five or more, most preferably six or more different perfume components. An upper limit of 300 perfume ingredients may be applied. Free perfume may preferably be present in an amount from 0.01 to 20 wt. %, more preferably 0.1 to 15 wt.%, more preferably from 0.1 to 10 wt.%, even more preferably from 0.1 to 6.0 wt.%, most preferably from 0.5 to 6.0 wt. %, based on the total weight of the composition.

Preferably some of the perfume components are contained in a microcapsule. Suitable encapsulating materials may comprise, but are not limited to; aminoplasts, proteins, polyurethanes, polyacrylates, polymethacrylates, polysaccharides, polyamides, polyolefins, gums, silicones, lipids, modified cellulose, polyphosphate, polystyrene, polyesters or combinations thereof.

Perfume components contained in a microcapsule may comprise odiferous materials and/or pro-fragrance materials.

Particularly preferred perfume components contained in a microcapsule are blooming perfume components and substantive perfume components. Blooming perfume components are defined by a boiling point less than 250°C and a LogP greater than 2.5. Substantive perfume components are defined by a boiling point greater than 250°C and a LogP greater than 2.5.

Preferably a perfume composition will comprise a mixture of blooming and substantive perfume components. The perfume composition may comprise other perfume components. It is commonplace for a plurality of perfume components to be present in a microcapsule. In the compositions for use in the present invention it is envisaged that there will be three or more, preferably four or more, more preferably five or more, most preferably six or more different perfume components in a microcapsule. An upper limit of 300 perfume ingredients may be applied.

Encapsulated perfume may preferably be present in an amount from 0.01 to 20 wt.%, more preferably 0.1 to wt.15 %, more preferably from 0.1 to 10 wt.%, even more preferably from 0.1 to 6.0 wt.%, most preferably from 0.5 to 6.0 wt.%, based on the total weight of the composition.

Rheology modifier

The compositions described herein preferably comprise a rheology modifier. Rheology modifiers are particularly preferred in compositions comprising microcapsules. Rheology modifiers may be inorganic or organic, polymeric or non polymeric. Non-limiting examples of suitable rheology modifiers include: pectine, alginate, arabinogalactan, carageenan, gellan gum, polysaccharides such as xanthum gum, guar gum, acrylates/acrylic polymers, water-swellable clays, fumed silicas, acrylate/aminoacrylate copolymers, salts and mixtures thereof.

Preferred rheology modifier for compositions comprising microcapsules herein include those selected from the group consisting of acrylate/acrylic polymers, gellan gum, fumed silicas, acrylate/aminoacrylate copolymers, water-swellable clays, polysaccharides such as xanthum gum and mixtures thereof. Most preferably the rheology modifier is selected from polysaccharides such as xanthum gum, acrylate/acrylic polymers, acrylate/aminoacrylate copolymers, and water-swellable clays. Most preferred rheology modifier are polysaccharides such as xanthum gum.

When present, a rheology modifier is preferably present in an amount of 0.001 to 10 wt.% percent, preferably from 0.005 to 5 wt.%, more preferably 0.01 to 3 wt.% of the composition.

Deposition polymers

The fabric softening composition of the present invention preferably comprises a cationic deposition polymer. The cationic polymer may be naturally derived or synthetic. Examples of suitable cationic polymers include: acrylate polymers, cationic amino resins, cationic urea resins, and cationic polysaccharides, including: cationic celluloses, cationic guars and cationic starches.

Preferably the cationic polymer is selected from; cationic polysaccharides and acrylate polymers. More preferably the deposition polymer is a cationic polysaccharide.

Examples of cellulosic polymers are those sold under the trade name LICARE ex. Dow, examples crosslinked polyacrylic acid polymers are available under the trade name Carbopol ex. Lubrizol.

The molecular weight of the cationic polymer is preferably greater than 50 000 g/mol, more preferably greater than 100 000 g/mol. The molecular weight is preferably less than 5 000 000 g/mol.

The compositions preferably comprise a cationic polymer at a level of from 0.05 to 5 wt.% of the composition, preferably from 0.1 to 4 wt.%, more preferably from 0.1 to 3 wt.%, even more preferably from 0.25 to 2.5 wt.%, most preferably from 0.25 to 1.5 wt.%.

Preservatives

The composition of the present invention preferably comprises preservatives. Preservatives are preferably present in an amount of 0.001 to 1 wt.% of the composition. More Preferably 0.005 to 0.5 wt. %, most preferably 0.01 to 0.1 wt.% of the composition

Preservatives can include anti-microbial agents such as isothiazolinone-based chemicals (in particular isothiazol-3-one biocides) or glutaraldehyde-based products. Also suitable are preservatives such as organic acids, sorbates and benzoates. Examples of suitable preservatives include Benzisothiazoline, Cloro-methyl-isothiazol-3-one, Methyl-isothiazol-3-one and mixtures thereof. Suitable preservatives are commercially available as Kathon CG ex. Dow and Proxel ex Arxada.

Optional ingredients

The compositions of the present invention may contain further optional laundry ingredients. Such ingredients include pH buffering agents, perfume carriers, hydrotropes, polyelectrolytes, anti-shrinking agents, anti-oxidants, anti-corrosion agents, drape imparting agents, anti-static agents, ironing aids, antifoams, colorants, pearlisers and/or opacifiers, natural oils/extracts, processing aids, e.g. electrolytes, hygiene agents, e.g. anti-bacterials and antifungals, thickeners, low levels of cationic surfactants such as quaternary ammonium compounds and skin benefit agents.

Form of composition

Preferably the fabric softening composition is an aqueous composition.

The viscosity of the fabric softening composition is preferably 30 to 15000 mPa.s, more preferably 50 to 1000 mPa.s, most preferably 80 to 800 mPa.s. The viscosity measurement can be carried out at 25°C, using a 4cm diameter 2°cone and plate geometry on a DHR-2 rheometer ex. TA instruments. In detail, the measurement can be conducted using a TA- Instruments DHR-2 rheometer with a 4cm diameter 2 degree angle cone and plate measuring system. The lower Peltier plate is used to control the temperature of the measurement to 25°C. The measurement protocol is a ‘flow curve’ where the applied shear stress is varied logarithmically from 0.01 Pa to 400 Pa with 10 measurement points per decade of stress. At each stress the shear strain rate is measured over the last 5 seconds of the 10 second period over which the stress is applied with the viscosity at that stress being calculated as the quotient of the shear stress and shear rate.

The fabric softening composition as described herein may be manufactured simply by adding mixing the ingredients with stirring. Preferably any free oil perfume and the natural oil are premixed with a non-ionic surfactant. If a rheology modifier is present, preferably it is pre-dispersed in water to form a homogenous mixture.

In use

The fabric softening composition may be added to the laundry process in either the wash or the rinse phase of the laundry process. Preferably the fabric softening composition is added during the rinse phase of the laundry process.

The compositions comprise less than 4 wt. % cationic and/or anionic surfactant (i.e. 0 to 4 wt.%). Therefore, the fabric softening composition alone does not deliver any detersive action, nor does it deliver fabric softening cationic surfactants. The compositions are intended for use either alone, or in combination with traditional laundry liquids (detergent or fabric conditioner) or powder. The fabric softening compositions described herein maybe used as a replacement for a fabric conditioner.

Preferably 2-150 ml, more preferably a volume of 2-100 ml, even more preferably a volume of ml 2-75ml, most preferably 2-50ml of the composition is added to the laundry process.

In another aspect of the present invention there is provided a method of softening fabrics, wherein a fabric softening composition as described herein is added to the rinse stage of a laundry process. In another aspect of the present invention there is provided a use of the compositions described herein to soften fabrics.

Examples

Table 1: Compositions

Natural oil: Pentaerythritol Tetrastearate¹ - Priolube 3987 ex. Croda

Film forming polymer: hydrolysed protein² - Coltide radiance ex. Croda

Non-ionic surfactant ³ - Eumulgin CO40 ex. BASF

Rheology modifier ⁴ - xanthan gum Example composition 2 was prepared by the following method. The rheology modifier was dispersed in cold water with vigorous mixing, then hot water using high shear mixing until a homogenous mixture was obtained. The film forming polymer was added to the dispersed rheology modifier with vigorous mixing. Separately, the non-ionic was melted at a temperature of about 60°C, then the free perfume and natural oil added to the non-ionic with medium stirring. The fragrance and oil premix was then added to the rheology modifier and film former with vigorous mixing. The perfume microcapsules and minors were then added and the mixture mixed until homogenous.

Table 2: Example fabric softening formulations

Ester oil: Pentaerythritol Tetrastearate¹ - Priolube 3987 ex. Croda

Hydrolysed protein ² - Coltide radiance ex. Croda

Samples of terry towel were washed 3 times with 35ml of a non-bio commercial laundry detergent in the wash and 20g of fabric softening compositions in the rinse according to Table 1. The wash conditions were as follows:

Fabrics: 12 terry towel clothes, ballast of woven cotton and woven polyester in 50:50 ratio

Wash cycle: 40°C cotton cycle

Machine: European front loading washing machine

Wash product: 35ml non-bio

Rinse product: 20g fabric softening composition according to table 1

Number of washes: 3 Drying: Terry towelling air dried, ballast tumble dried

After 3 washes the terry toweling clothes were assessed using a PhabrOmeter ex. Nu Cybertek.

The mean average relative hand values were calculated.

Table 3: Results

The combination of a natural oil and film forming polymer provides improved relative hand value. This represents improved softening.

Claims

1. A fabric softening composition comprising: a Natural oil; b Film forming polymer; c 0 to 4 wt.% anionic and/or cationic surfactant wherein the natural oil comprises plant oils and/or the esterified fatty acids of plant oils, and wherein the film forming polymer comprises: polyvinyl alcohol; polyvinyl pyrrolidone; polyethylene glycol; polyethylene oxide; polyesters including co-polyesters; hydrolysed proteins and derivatives thereof or any combinations thereof.

2. A fabric softening composition according to claim 1 , wherein the natural oil comprises seed oils and/or the esterified fatty acids thereof.

3. A fabric softening composition according to any preceding claim, wherein the natural oil is selected from; triglycerides and/or ester oils.

4. A fabric softening composition according to any preceding claim, wherein the composition comprises 0.25 wt. % to 15 wt.% natural oil.

5. A fabric softening composition according to any preceding claim, wherein the film forming polymer is selected from polymers comprising hydrolysed proteins and/or polyesters, including co-polyesters.

6. A fabric softening composition according to any preceding claim, wherein the composition comprises 0.005 to 10 wt.% film forming polymer.

7. A fabric softening composition according to any preceding claim, wherein the composition comprises 0.5 to 15 wt.% non-ionic surfactant.

8. A fabric softening composition according to any preceding claim, wherein the composition comprises 0.5 to 20 wt.% perfume ingredients.

9. A fabric softening composition according to any preceding claim, wherein the composition comprises rheology modifier. A method of delivering softening to fabrics, wherein a fabric softening composition according to claims 1 to 9 is added in the wash or rinse stage. Use of a fabric softening composition according to claims 1 to 9 to soften fabrics.