EP2307536A1 - Microcapsules in surfactant-containing compositions - Google Patents

Abstract

A composition comprising, 1-99%wt of surfactant and at least one micro-particle having a diameter of 100nm-2mm, said micro-particle comprising: i) a core comprising a hydrophobic benefit agent (preferably a perfume or a dye), and, ii) a shell comprising an uncharged hydrophobically-modified, water-soluble film-forming polymer (preferably a modified PVOH), whereby the film remains substantially intact in the presence of surfactant but dissolves when the concentration of surfactant is reduced, thereby releasing the benefit agent. The invention provides a process for treatment of surfaces comprising the step of contacting a composition according to the invention with fabric, hair, or living tissue. The invention also provides a method for preparing compositions according to claims 1-13 which comprises the steps of: a) providing an aqueous solution of uncharged, hydrophobically-modified, film forming polymer having a hydrophobic benefit agent dispersed therein, b) forming a layer of the uncharged, hydrophobically-modified, film forming polymer around the dispersed hydrophobic benefit agent, and c) stabilizing said layer with surfactant.

Description

MICROCAPSULES IN SURFACTANT- CONTAINING COMPOSITIONS

Field Of The Invention

The present invention relates to surfactant-containing compositions which include particles comprising a benefit agent and their use, particularly as laundry detergent or fabric conditioner products. The invention is also applicable to other surfactant-containing products such as those suitable for use on skin and hair and on hard surfaces.

Background and Prior Art

The invention will be particularly described with reference to the benefit agents being perfumes, dyes and cationic surfactants.

Perfumes are important and expensive components of laundry detergent compositions and other surfactant containing products. It is important to ensure that perfumes are not lost during processing or on storage of the compositions and that they deposit onto articles and surfaces being washed. Being volatile, perfumes are prone to evaporate from a composition, especially if the composition is subjected to elevated temperatures. Methods for deposition of perfume components and other benefit agents from surfactant-containing compositions are diverse and perfume is often incorporated into a carrier or other delivery system. Carrier systems for perfumes are typically based on encapsulation or entrapment of the perfume within a matrix. The perfume may simply be emulsified but deposition onto a substrate, such as fabric, skin or hair, is often inefficient and problems with poor retention or stability may be found. Preparation of materials by diffusion of the perfume into a carrier can suffer from complex preparation, long times of diffusion, poor retention of the perfume in the matrix and subsequent poor substrate deposition.

Perfume encapsulates have been proposed as a means of overcoming these problems. EP 332175 (Lion, 1988) discloses a method of producing water- insoluble microcapsules comprising the steps of mixing (i) an aqueous dispersion containing capsules having a wall-membrane containing PVOH and an aqueous solution containing an electrolyte and (ii) a cross-linking agent comprising an aldehyde. The electrolyte stabilises the capsules until the wall-membrane has been cross-linked. These particles are stable to water washing and in aqueous dispersion.

Commercially available perfume encapsulates are based on aminoplast materials and may be modified with cationic materials to improve deposition on surfaces such as textiles. These charged capsules encounter difficulties if used in an environment which contains anionic surfactants as the capsules and the surfactant will interact.

Poly-vinyl alcohol (PVOH) has been used to form water-soluble sachets containing cationic surfactants. WO 2004/031271 discloses modified poly-vinyl alcohol (PVOH) sachets which are surrounded by films with a preferred average thickness of from 50 to 500 microns. The sachets preferably contain from 0.5 ml to 100 ml of a material such as a laundry conditioner.

GB 0803165.0 (filed 8^th Feb 2008) discloses a microcapsule, having a diameter of less than 2mm comprising: (a) a benefit agent (such as perfume), and (b) a water soluble polymeric film-forming material modified with both a hydrophobic group and a first charged, dehvatising group(s). The film: remains substantially intact in the presence of a surfactant, and disintegrates when the concentration of the surfactant reduces sufficiently, thereby releasing the benefit agent.

Dyes are another useful component of many surfactant-containing compositions. For example, in laundry compositions dyes can be used as "shading" or "hueing" agents. Dyes may be present in hair products to colour the hair. As with perfumes, dyes are difficult to deposit from surfactant compositions as the surfactant has a tendency to assist removal of the dye from the article or surface being washed. The same is true of many other benefit agents.

Brief Description of the Invention

We have determined that a hydrophobically modified polymer (particularly modified polyvinyl alcohol (mPVOH)) which does not have the charged dehvatising group required by GB 0803165.0 can be used to coat micro-particles which comprise a benefit agent and that these particles, while stable at high surfactant concentrations, release the benefit agent at low surfactant concentrations. These micro-particles are far smaller than the sachets of WO 2004/031271 and unlike the cross-linked, water-insoluble particles of EP 332175, do not need to be crushed to release their contents.

Accordingly, the first aspect of the invention provides a composition comprising, 1 -99%wt of surfactant and at least one micro-particle having a diameter of 100nm-2mm, said micro-particle comprising:

i) a core comprising a hydrophobic benefit agent, and,

ii) a shell comprising an uncharged hydrophobically-modified, water-soluble film-forming polymer, whereby the film remains substantially intact in the - A -

presence of surfactant but dissolves when the concentration of surfactant is reduced, thereby releasing the benefit agent

Preferably, the micro-particles have a diameter of 1 -1000 microns, more preferably 1 -100 microns, most preferably 1 -50 microns.

According to a further aspect of the present invention there is provided a method for preparing a composition according to the present invention which consists of the steps of:

a) providing an aqueous solution of uncharged, hydrophobically-modified, film forming polymer having a hydrophobic benefit agent dispersed therein,

b) forming a layer of the uncharged, hydrophobically-modified, film forming polymer around the dispersed hydrophobic benefit agent, and

c) stabilizing said layer with surfactant.

In the context of the present invention, hydrophobic benefit agents have a ClogP greater than 0.5, preferably greater than 1 and more preferably greater than 2. Without wishing to be bound by theory, it is believed that when the core and the polymer are brought together, the hydrophobic moiety causes the polymer to aggregate at the water-core interface. In a particularly preferred embodiment, when the temperature of the solution is raised above the lower critical solution temperature (LCST) of the polymer, this coating crystallizes, becoming insoluble in water and forming part of the shell. When a suitable surfactant is added, a further layer is formed by interaction between the surfactant and the hydrophobic moieties on the polymer, thus creating a shell around the core. When the temperature is dropped below the LCST, the surfactant-polymer shell remains stable, provided that sufficient surfactant is present. The shell is stable in a surfactant containing product. However, upon dilution of the product the shell becomes unstable and the benefit agent is released.

Preferably, the modified polymer has:

a) a solubility or dispersibility at 2O⁰C in water which contains a concentration of one or more anionic/non-ionic or cationic surfactants of greater than 1g/L of less than 0.5 g per hour, and,

b) a solubility or dispersibility of greater than 0.5 g per hour when the concentration of anionic/non-ionic or cationic surfactant in water is less than 1g/L.

The invention finds particular utility when applied to benefit agents which are droplets of oily material such as free perfume oil or even to particles which comprise pre-encapsulated perfumes, in particular to urethane or aminoplast encapsulates, (including, melamine-formaldehyde) encapsulates and to poly- olefinic encapsulates (including those based on poly(meth)acrylates). Other suitable oily materials include oils having oil-soluble dyes, or other benefit agents dispersed therein. In a preferred embodiment the benefit agent has a solubility in water (at 20 Celcius) of less than 600mg/L, preferably less than 200mg/L.

The invention can also be used to encapsulate charged species, preferably cationic materials, so that they can be added to a solution containing materials of the opposite charge without causing flocculation/instability.

Preferably, the hydrophobic dehvatising group of the polymer is derived from a parent material having a ClogP of greater than 0.5. According to a further aspect of the present invention there is provided a process for treatment of fabrics comprising the step of contacting a composition according the present invention, in neat or dilute form, with fabric. It should be noted that the use of the invention is not limited to laundry applications and can be used on other surfaces such as that of hair or living tissue. The present invention can be used to stabilize and deliver hydrophobic benefit agents from any surfactant-containing system which will undergo significant dilution during use. Accordingly, the invention further provides a process for the treatment of a surface comprising the step of contacting a composition according the present invention, in neat or dilute form, with the surface.

Detailed Description of the Invention

In order that the invention can be further understood it is described below with particular reference to the preferred features of specific elements of the invention.

Polymer

Polymers suitable for use as whole or part of the backbone of the hydrophobically modified water soluble polymer are preferably selected from the group consisting of polyvinyl alcohol, polyvinyl acetate, cellulose ethers, polyethylene oxide, starch, polyvinylpyrrolidone, polyacrylamide, polyvinyl methyl ether-maleic anhydride, polymaleic anhydride, styrene maleic anhydride, hydroxyethylcellulose, methylcellulose, polyethylene glycols, carboxymethylcellulose, polyacrylic acid salts, alginates, acrylamide copolymers, guar gum, casein, ethylene-maleic anhydride resin series, polyethyleneimine, ethyl hydroxyethylcellulose, ethyl methylcellulose and hydroxyethyl methylcellulose. Copolymeric mixtures of polymers derived from the aforementioned backbones are also suitable. Preferably the water soluble polymer has a backbone comprising side chain hydroxyl groups.

The most preferred backbone for the water soluble polymer comprises polyvinyl alcohol (PVAc), preferably with an average a molecular weight of from 10kD to 30OkD preferably from 2OkD to 20OkD most preferably from 75kD to 175kD. .

Polyvinyl alcohol (PVOH) can be supplied in a form comprising a certain amount of polyvinyl acetate (PVAc), in that a level of the hydroxyl groups (OH) of the PVOH material is substituted with acetate groups (OCOCH₃). Hydrolysis of PVAc is a common way to make PVOH. However, to achieve complete hydrolysis is expensive and typical materials are only up to around 99% hydrolysed. Thus the PVOH used herein generally comprise at some PVAc. The PVOH materials (either before or after hydrophobic modification) may comprise from 0.01 to 40% PVAc, preferably from 0.01 to 20%, more preferably from 0.1 to 15%, most preferably 0.5 to 10%, based on the % of the total number of monomers making up the polymer. As used herein, the term PVOH includes PVOH compounds with a PVAc level as previously defined. In this context, the reference to the material being uncharged means that the PVOH comprises no charged derivatising group as required by GB 0803165.0, not that it is free of residual PVAc.

Preferably the modified polymer has an average degree of hydrolysis within the range from 70 to 99%. Preferably, the modified polymer has a viscosity as a 4% solution at 20⁰C measured according to DIN 53 015 within the range 1 to 100 mPa.s.

As noted above, the water-soluble polymer is modified to comprise hydrophobic substituents. Preferred hydrophobic derivatisation groups include those based on parent groups selected from acetals, aldehydes, ketals, esters, fluorinated organic compounds, ethers, alkanes, alkenes and aromatics. Highly preferred hydrophobic substituents are hydrocarbyl groups of C₄ to C22 carbon chain length. These hydrocarbyl groups may be alkyl or alkenyl based, which can be straight chain, branched or comprise rings; it may also or alternatively incorporate aromatic moieties.

More preferably the hydrocarbyl group has a carbon chain length of from C₄ to C20, even more preferably from C₄ to C15, most preferably from C₄ to C10, for example, from C₄ to C₈.

Hydrocarbyl chain lengths greater than C22 are undesirable as the parent material from which the dehvatising group is obtained reacts poorly or not at all with the polymeric backbone. Hydrocarbyl groups shorter than C4 provide negligible additional hydrophobicity.

Especially preferred materials suitable for use to introduce the hydrophobic dehvatisation groups onto the water soluble polymer are aldehydes such as butyraldehyde, octyl aldehyde, dodecyl aldehyde, 2-ethyl hexanal, cyclohexane carboxy-aldehyde, citral and 4-aminobutyraldehyde dimethyl acetal.

The hydrophobic material is preferably present in the polymer at a level from 0.1 to 40% by weight, based on the total weight of the polymer, more preferably from 2 to 30%, most preferably from 5 to 15%.

Where the polymeric backbone is based on polyvinyl alcohol, the hydrophobic dehvatisation material is preferably present at a level such that the number ratio of the hydrophobic groups to the free hydroxyl pairs on the backbone is from 1 :3 to 1 :30, more preferably from 1 :4 to 1 :20, most preferably 1 :7 to 1 :15.

Variation of the level of derivatisation of the polymer enables the properties of the shell to be modified such that the shell will release the materials in the core at a particular level of surfactant. Thus, shells can be made which are stable in the surfactant-containing product but which become unstable at the level of surfactant found in a wash-liquor (for example, which become unstable in the main-wash of a laundry process or during skin or hair treatment with the product in the presence of water). Such systems can assist in the stability of the benefit agent during product storage. In the alternative, shells may be stable a wash liquor, but become unstable during rinsing of the wash-liquor from the surface or article being treated. Hence, particles can be formed which release the benefit agent during a rinsing process, and reduce the tendency of the benefit agent to be removed by the surfactant. More than one type of particle may be present in a given product to prevent interaction of components, for example sunscreens, which might otherwise interact.

Other Film Components

It can be advantageous for the water soluble film to be provided from a material which has a partly cross-linked polymeric structure. However, the level of cross- linking should be kept low so as to avoid the formation of an insoluble material. It is preferable that the material from which the film is made is not cross-linked at all.

Particularly suitable cross-linking agents include formaldehyde; polyesters; epoxides, amidoamines, anhydrides, phenols; isocyanates; vinyl esters; urethanes; polyimides; acrylics; bis(methacrylkoxypropyl) tetramethylsiloxane (styrenes, ethylmethacrylates); n-diazopyruvates; phenyboronic acids; cis-platin; divinylbenzene; polyamides; dialdehydes; thallyl cyanurates; N-(-2- ethanesulfonylethyl)pyhdinium halides; tetraalkyltitanates; mixtures of titanates and borates or zirconates; polyvalent ions of Cr, Zr, Ti; dialdehydes, diketones; alcohol complexes of organotitanates, zircoates and borates and copper (II) complexes. For PVOH-based films, the preferred cross-linking agent is a metalloid oxide such as borate, tellurate, arsenate, and precursors thereof. Other known cross-linkers include the vanadyl ion, titanium ion in the plus three valence state, or a permanganate ion (disclosed in patent US 3,518,242). Alternative cross-linkers are given in the book: Polyvinylalcohol - Properties and applications, Chapter 9 by CA. Finch (John Wiley & Sons, New York, 1973).

The film may incorporate a plasticiser and/or crystallinity disruptor. It is to be understood that the term "plasticiser" and phrase "crystallinity disruptor" are interchangeable such that a reference to one is an implicit reference to the other.

Water itself is a suitable plasticizer for mPVOH films but other common plasticizers include: Polyhydroxy compounds, e.g. glycerol, thmethylolpropane, diethylene glycol, triethylene glycol, sorbitol, dipropylene glycol, polyethylene glycol; starches, e.g. starch ether, estehficated starch, oxidized starch and starches from potato, tapioca and wheat; cellulosics/carbohydrates, e.g. amylopectin, dextrin, carboxymethyl-cellulose and pectin. Amines are particularly preferred plasticisers.

Suitable plasticisers for mPVP-based films may be chosen from one or more of: phosphates e.g. tris(2-ethylhexyl)phosphate, isopropyl diphenyl phosphate, tributoxyethylphosphate; polyols e.g. glycerol, sorbitol, diethylene glycol diperlargonate, polyethylene glycol di-2-ethylhexanoate, dibutyl tartrate; polyol esters e.g. hydroxy containing polycaprolactones, hydroxy containing poly-L- lactide; lower phthalates e.g. dimethyl phthalate, diethyl phthalate, dibutyl phthalate; and sulfonamides e.g. toluene sulfonamide, N-ethyltoluene sulfonamide.

Suitable plasticizers for mPEO-based films may be selected from one or more of: phosphates e.g. tris(2-ethylhexyl)phosphate, isopropyl diphenyl phosphate, tributoxyethylphosphate; polyols e.g. glycerol, sorbitol, diethylene glycol diperlargonate, polyethylene glycol di-2-ethylhexanoate, dibutyl tartrate; lower phthalates e.g. dimethyl phthalate, diethyl phthalate, dibutyl phthalate; and sulphonamides e.g. toluene sulphonamide, N-ethyltoluene sulphonamide.

Encapsulating Surfactants

The surfactant used to form the gel barrier with the film is preferably anionic, although nonionic or cationic surfactants can be used. If the particle is for use within a laundry detergent, the surfactant used is preferentially anionic or nonionic.

Anionic products are also typically used in hair and/or skin cleaning compositions.

If the particle is for use within a laundry rinse conditioner, then the surfactant is preferably cationic or nonionic. Similarly, cationic surfactants are typically used in hair conditioning products.

Suitable anionic surfactants are: linear alkyl benzene sulphonate (LAS), primary alkyl sulphate (PAS), fatty ether sulphates (LES), secondary alkane sulphonate, α-olefin sulphonate, α-sulphonic fatty acid methyl ester, methyl ester sulphonates (MES). The preferred surfactants are LAS, PAS, LES, and mixtures [hereof. Preferred materials include including sodium fatty alcohol sulphate, ammonium fatty alcohol sulphate, ammonium alcohol ether sulphate, sodium fatty ether sulphate, alcohol ether carboxylate and nonylphenol polyoxyethylene ether carboxylate. The most preferred surfactant for laundry compositions is LAS.

Suitable non-ionic surfactants include ethoxylated linear and branched alcohols, ethoxyiated alkyl phenols, fatty acid esters, amine and amide derivatives, aikylpoiygiycosides, EO/PO block copolymers, polyalcohols and ethoxyiated poiyaicohois. For hair and skin products the surfactant present is preferably an anionic surfactant has from 8 to 14 carbons, more preferably from 10 Io 12 and most preferably 12 carbons. More preferably, these carbons are present in a single alkyi group. Preferred anionic surfactants for hair and skin products comprise include alkali metal alky! sulphates, more preferably the alkyi ether sulphates. Particularly preferred anionic cleansing surfactants include sodium lauryl ether sulphate. Typically the cleansing phase of a hair or skin product (that is other than any conditioning or moisturising phase) comprises from 27 to 70% by weight cleansing surfactant, preferably from 35 to 50% by weight of the composition.

!n hair and skin conditioning products, preferred cationic surfactants have the formula N+(R¹)(R-)(R³)(R^"1), wherein R¹, R², R³ and R^A are independently (C 18 to C30) alkyi or benzyl. Preferably, one, two or three of R¹, R'^:, R^:i and R⁴ are independently (C18 to C30) aikyl and the other R¹. R², R³ and R^" group or groups are {C1-C6) alkyi or benzyl. Optionally, the alkyi groups may comprise one or more ester (-OGO- or -GOO-) and/or ether (-O-) linkages within the alkyi chain. Aikyl groups may optionally be substituted with one or more hydroxyl groups. Aikyl groups may be straight chain or branched and, for aikyl groups having 3 or more carbon atoms, cyclic. The aikyl groups may be saturated or may contain one or more carbon-carbon double bonds (e.g., oleyl). Alkyi groups are optionally ethoxyiated on the aikyl chain with one or more ethyleneoxy groups.

Suitable cationic surfactants for use in conditioner compositions according to the invention include cetyltπmethylamrnomurn chloride, behenyltrimethylammoπium chloride, cetyipyridinium chloride, tetramethylammonium chloride. tetraethylammonium chloride, stearyldirnethylbeπzylarnmoπium chloride, cocotπmethyiammonlum chloride, PEG-2-oleammonιum chloride and the corresponding hydroxides thereof. Further suitable cationic surfactants include those materials having the CTFA designations Guaternium-5. Quatemium-31 and Quaternium-18. Mixtures of any of the foregoing materials may also be suitable. A particularly useful cationic surfactant for use in conditioners according to the invention is cetyitπmethyiammonium chloride, available commercially, for example as GENAMIN CTAG. ex Hoechst Gelanese. Another particularly useful cationic surfactant for use in conditioners according to the invention is behenyltrimethylammonium chloride, available commercially, for example as GENAMIN KDMP, ex Ciariant

Another example of a class of suitable cationic surfactants for use in the invention, either alone or in admixture with one or more other cationic conditioning surfactants, are amidoammes. Preferred amidoammes useful herein include sfearamido-propyidimethylamine, stearamidopropyidielhyiamine, stearamidoethyldiethylamine, stearamidoethyldimethyiamine, palmitamido- propyidimelhyiamsne. palmit-amidopropyidiethylamine, palmitamidoethyldiethylamine, palmitamido-ethyldimethylamine. behenamidopropyldimethylarnine. behenamido-propyldiethylmine, behenamidoethyidiethyiamine, behenamidoethyidimethylamine, arachidamidopropyidimethylamine, arachidamidopropyldiethylamine, arachid- amidoethyidielhyiamine, arachidamidoelhyidimethyiamiπe, and mixtures thereof.

Particularly preferred amsdoamsnes useful herein are stearamidopropyidimethylamine. stearamidoethyldiethylamine, and mixtures thereof.

Commercially available amidoammes useful herein include: stearamidopropyidimethylamine with tradenames LEXAMiNE S-13 available from Index (Philadelphia Pennsylvania, USA) and AMiDOAMINE MSP available from Nikko (Tokyo, Japan), sfearamidoethyidiethyiamine with a tradename AMSDOAMSNE S available from Nikko, behenamidopropyldimethylamine with a lradename INCROMINE BB available from Croda (North Humberside, England), and various amidoamines with tradenames SCHERCODINE series available from Scher (Ciiflon New Jersey, USA).

The level of cahonic surfaclant in hair conditioning products will generally range from 0.01 to 10%, more preferably 0.02 to 7.5%, most preferably 0.05 to 5% by total weight of cationic surfactant based on the total weight of the composition.

A variety of benefit agents can be incorporated using this invention. Preferred benefit agents include perfumes, lubricants any other oily materials. Particularly preferred benefit agents include, but not limited to, the following:

a) silicone oils, resins, and modifications thereof such as linear and cyclic polydimethylsiloxanes, amino-modified, allcyl, aryl, and alkylaryl silicone oils, which preferably have a viscosity of greater than 50,000 cst;

b) perfume components including fragrance, perfumery, and essential oils and resins;

c) photo-active materials including dyes and pigments, including inorganic compounds with hydrophobically-modified surface and/or dispersed in an oil or a hydrophobic liquid, also including fluorescing agents: for example: 2,5-bis(2-benzoxazolyl) thiophene for use on fabrics (such as cotton, nylon, polycotton or polyester) in laundry products; UV protecting agents: such as sunscreens for example: octyl methoxycinnamate (Parsol MCX), butyl methoxydibenzoylmethane (Parsol 1789) and benzophenone-3 (Uvinul M- 40), and ferulic acid, organic sunscreen actives, for example, octylmethoxy cinnamate; d) antimicrobial agents, for example, 2-hydroxy-4,2,4-trichlorodiphenylether; antidandruff agents: for example: zinc pyhthione;

e) skin lightening agents, for example 4-ethylresorcinol

f) ester solvents; for example, isopropyl myristate;

g) lipids and lipid like substance, for example, cholesterol; fish and vegetable oils, hydrophobic plant extracts; waxes;

h) hydrocarbons such as paraffins, petrolatum, and mineral oil

i) pre-encapsulated materials e.g. perfume encapsulates

j) surfactants of the opposite charge to the encapsulating surfactants.

k) further pharmaceutically and otherwise biologically active compounds, such as biocides and agrochemicals

Among the most preferred benefit agents are perfume components. Perfume components include both odiferous materials and pro-fragrance materials whether encapsulated or not. Also among the preferred benefit agents are oily materials used as carriers for minor amounts of oil-soluble benefit agents, i.e. in amounts of less than 50%wt of the carrier. Such oil soluble benefit agents include hydrophobic dyes and other hydrophobic actives such as agrochemicals.

The pro-fragrance can, for example, be a food lipid. Food lipids are oily materials and typically contain structural units with pronounced hydrophobicity. The majority of lipids are derived from fatty acids. In these 'acyl' lipids the fatty acids are predominantly present as esters and include mono-, di-, triacyl glycerols, phospholipids, glycolipids, diol lipids, waxes, sterol esters and tocopherols. In their natural state, plant lipids comprise antioxidants to prevent their oxidation. While these may be at least in part removed during the isolation of oils from plants some antioxidants may remain. These antioxidants can also be pro-fragrances. In particular, the carotenoids and related compounds including vitamin A, retinol, retinal, retinoic acid and provitamin A are capable of being converted into fragrant species including the ionones, damascones and damscenones. Preferred pro- fragrance food lipids include olive oil, palm oil, canola oil, squalene, sunflower seed oil, wheat germ oil, almond oil, coconut oil, grape seed oil, rapeseed oil, castor oil, corn oil, cottonseed oil, safflower oil, groundnut oil, poppy seed oil, palm kernel oil, rice bran oil, sesame oil, soybean oil, pumpkin seed oil, jojoba oil and mustard seed oil. Perfume components which are odiferous materials are described in further detail below.

Perfumes as benefit agents:

The perfume is typically present in an amount of from 10-85% by total weight of the particle, preferably from 20 to 75% by total weight of the particle. The perfume suitably has a molecular weight of from 50 to 500.

Useful components of the perfume 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 Flavour Ingredients, 1975, CRC Press; Synthetic Food Adjuncts, 1947 by

M. B. Jacobs, edited by Van Nostrand; or Perfume and Flavour 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, i.e., of imparting an odour and/or a flavour or taste to a consumer product traditionally perfumed or flavoured, or of modifying the odour and/or taste of said consumer product.

By perfume in this context is not only meant a fully formulated product fragrance, but also selected components of that fragrance, particularly those which are prone to loss, such as the so-called 'top notes'.

Top notes are defined by Poucher (Journal of the Society of Cosmetic Chemists 6(2):80 [1955]). Examples of well known top-notes include citrus oils, linalool, linalyl acetate, lavender, dihydromyrcenol, rose oxide and cis-3-hexanol. Top notes typically comprise 15-25%wt of a perfume composition and in those embodiments of the invention which contain an increased level of top-notes it is envisaged at that least 20%wt would be present within the encapsulate.

Typical perfume components which it is advantageous to encapsulate include those with a relatively low boiling point, preferably those with a boiling point of less than 300, preferably 100-250 Celsius.

It is also advantageous to encapsulate perfume components which have a low LogP (i.e. those which will be partitioned into water), preferably with a LogP of less than 3.0. These materials, of relatively low boiling point and relatively low LogP have been called the "delayed blooming" perfume ingredients and include the following materials:

AIIyI Caproate, Amyl Acetate, Amyl Propionate, Anisic Aldehyde, Anisole,

Benzaldehyde, Benzyl Acetate, Benzyl Acetone, Benzyl Alcohol, Benzyl Formate, Benzyl lso Valerate, Benzyl Propionate, Beta Gamma Hexenol, Camphor Gum, Laevo-Carvone, d-Carvone, Cinnamic Alcohol, Cinamyl Formate, Cis-Jasmone, cis-3-Hexenyl Acetate, Cuminic Alcohol, Cyclal C, Dimethyl Benzyl Carbinol, Dimethyl Benzyl Carbinol Acetate, Ethyl Acetate, Ethyl Aceto Acetate, Ethyl Amyl Ketone, Ethyl Benzoate, Ethyl Butyrate, Ethyl Hexyl Ketone, Ethyl Phenyl Acetate, Eucalyptol, Eugenol, Fenchyl Acetate, Flor Acetate (tricyclo Decenyl Acetate), Frutene (thcyclco Decenyl Propionate), Geraniol, Hexenol, Hexenyl Acetate, Hexyl Acetate, Hexyl Formate, Hydratropic Alcohol, Hydroxycitronellal, Indone, lsoamyl Alcohol, lso Menthone, lsopulegyl Acetate, Isoquinolone, Ligustral, Linalool, Linalool Oxide, Linalyl Formate, Menthone, Menthyl Acetphenone, Methyl Amyl Ketone, Methyl Anthranilate, Methyl Benzoate, Methyl Benyl Acetate, Methyl Eugenol, Methyl Heptenone, Methyl Heptine Carbonate, Methyl Heptyl Ketone, Methyl Hexyl Ketone, Methyl Phenyl Carbinyl Acetate, Methyl Salicylate, Methyl-N-Methyl Anthranilate, Nerol, Octalactone, Octyl Alcohol, p-Cresol, p-Cresol Methyl Ether, p-Methoxy Acetophenone, p-Methyl Acetophenone, Phenoxy Ethanol, Phenyl Acetaldehyde, Phenyl Ethyl Acetate, Phenyl Ethyl Alcohol, Phenyl Ethyl Dimethyl Carbinol, Prenyl Acetate, Propyl Bornate, Pulegone, Rose Oxide, Safrole, 4-Terpinenol, Alpha-Terpinenol, and /or Viridine

It is commonplace for a plurality of perfume components to be present in a formulation. In the encapsulates of the present invention it is envisaged that there will be four or more, preferably five or more, more preferably six or more or even seven or more different perfume components from the list given of delayed blooming perfumes given above present in the encapsulated perfume.

Another group of perfumes with which the present invention can be applied are the so-called 'aromatherapy' materials. These include many components also used in perfumery, including components of essential oils such as Clary Sage, Eucalyptus, Geranium, Lavender, Mace Extract, Neroli, Nutmeg, Spearmint, Sweet Violet Leaf and Valerian. By means of the present invention these materials can be transferred to textile articles that will be worn or otherwise come into contact with the human body (such as handkerchiefs and bed linen). As noted above the core of the particles of the present invention can itself be an encapsulated perfume such a melamine/urea/formaldehyde encapsulate. The present invention can be used to "improve" leaky capsules by adding a further layer which is impervious to the perfume. In use in a cleaning process, the further layer (PVOH and surfactant), is removed. The capsules can then release perfume over a period of time and/or, in the case of laundry, when garments are worn and the capsules are crushed.

As will be illustrated below with reference to specific examples, the present invention can be employed to encapsulate pre-encapsulated benefit agents (such as perfumes) which have been, in their first encapsulation, provided with a cationic capsule. Such cationic capsules are believed to show better deposition on, for example, cloth than uncharged capsules. However, they show negative interactions with anionic surfactants. By further encapsulating these capsules according to the present invention these unwanted interactions can be reduced.

Dyes as Benefit Agents

Dyes are a benefit agent which may be present in the particles as an alternative to or in addition to perfumes. Dyes are typically present at levels which make them effective as hueing (shading) dye. The hueing dye is preferably blue or violet. Suitable and preferred hueing dyes are those described in WO05/003274, WO06/032327, WO 06/032397, EP08167033, WO 06/045375, WO 06/053598 and WO 08/017570. Mixtures of hueing dyes may be used.

Preferred classes of hueing dyes are cationic thiazolium dyes, cationic isothiazolium dyes, cationic azine dyes, cationic pyridine/pyridazine dyes, acid azine dyes, hydrophobic anthraquinone dyes and hydrophobic azo dyes. The most preferred hueing dyes are those selected from: Direct Violet 9; Direct Violet 35; Direct Violet 51 ; Direct Violet 99; Acid Violet 50; Disperse Violet 28 and, Solvent Violet 13. Where some other benefit agent is encapsulated according to the present invention, the dyes may be present as an additional adjunct either within the capsule or in the bulk of the product.

Surfactants as Benefit Agents

The benefit agent may itself be a surfactant or may include a surfactant. In laundry products, for example, the benefit agent may be a cationic surfactant which is prevented from interacting with anionic surfactant in the bulk of the product by the shell formed around it. For laundry products, suitable such cationic surfactants are water soluble cationic species having at least one alkyl or alkenyl chain. It is preferable that the sum of the length of the alkyl chains is less than 20. Preferred cationic surfactants are: quaternary ammonium compounds having single long-chain aliphatic groups. Cetylthmethylammonium chloride is particularly preferred.

Other Benefit Agents

The benefit agent may comprise a silicone, preferably as a conditioning agent, especially for products suitable for use in hair and skin products. In the alternative or in addition silicone conditioning agents may be present in the bulk of the composition. Particularly preferred silicone conditioning agents are silicone emulsions such as those formed from silicones such as polydiorganosiloxanes, in particular polydimethylsiloxanes which have the CTFA designation dimethicone, polydimethyl siloxanes having hydroxyl end groups which have the CTFA designation dimethiconol, and amino-functional polydimethyl siloxanes which have the CTFA designation amodimethicone.

Also suitable are silicone emulsions in which certain types of surface active block copolymers of a high molecular weight have been blended with the silicone emulsion droplets, as described for example in WO03/094874. In such materials, the silicone emulsion droplets are preferably formed from polydiorganosiloxanes such as those described above. One preferred form of the surface active block copolymer is according to the following formula:

HO(CH₂CH₂θ)χ(CH(CH₃)CH₂θ)_y(CH2CH2O)_x H

wherein the mean value of x is 4 or more and the mean value of y is 25 or more.

Another preferred form of the surface active block copolymer is according to the following formula:

(HO(CH2CH2θ)_a(CH(CH3)CH2θ)_b)2-N-CH2-CH2-N((OCH2CH(CH3))b(OCH₂CH2)a OH)2

wherein the mean value of a is 2 or more and the mean value of b is 6 or more.

Mixtures of any of the above described silicone emulsions may also be used.

The above-described silicone will generally be present in a composition of the invention at levels of from 0.05 to 15%, preferably from 0.5 to 12% by total weight of silicone based on the total weight of the composition.

Further hydrophobic benefit agents can be envisaged. Many agrochemical materials are hydrophobic and maybe potentially hazardous in use. Such materials can be present as a solution in an oily material which forms the core of the particles according to the present invention. The presence of the surfactant stabilized shell around these cores is believed to retard the release of these materials until the composition is diluted, preferably just prior to use, thus reducing unwanted exposure.

Specific water-insoluble agrochemical materials, with a solubility of less than or equal to 200mg/L include: Gamma-cyhalothrin, Deltamethrin, Fluvalinate, Fenvalerate, Esfenvalerate, Flucycloxuron, Cyfluthhn, Metaflumizone, Clofentezine, Bifenthrin, Novaluron, Alpha-cypermethrin, Flufenoxuron, Lambda- cyhalothrin, Acequinocyl, Cypermethrin, Zeta-cypermethhn, Ethalfluralin, Teflubenzuron, Pyhdaben, Cyflufenamid, Fenbutatin oxide, Tefluthrin, Chlorfluazuron, Acrinathrin, Etofenprox, Fenpyroximate, Hexaflumuron, Cyflumetofen, Flubendiamide, Bisthfluron, Dimethomorph, Thflumuron, Azocyclotin, Silthiofam, Lufenuron, Picolinafen, Quinoxyfen, Diflufenican, Spirodiclofen, Benzobicyclon, Cinidon-ethyl, Diafenthiuron, Sulphur, Quinclorac, Benfluralin, Prothiofos, Etoxazole, Diflubenzuron, Pyraflufen, Cycloprothrin, Bifenox, Chlorethoxyfos, Hexythiazox, Amitraz, Fenazaquin, Carbosulfan, Famoxadone, Chlorfenapyr, Cyazofamid, Oxyfluorfen, Benzofenap, Spiromesifen, Fluazinam, Dinocap, Flumiclorac, Noviflumuron, Permethhn, Indoxacarb, Propargite, Pentoxazone, Thfluralin, Diflovidazin, Meptyldinocap, Paclobutrazol, Quizalofop, Pencycuron, Butralin, Endosulfan, Pendimethalin, Fenpropathhn, Fluacrypyhm, Oxadiargyl, Pyriproxyfen, Dithianon, Quintozene, Buprofezin, Metrafenone, Chlorthal, Lactofen, Oxadiazon, Thfloxystrobin, Propaquizafop, Zoxamide, Metamifop, Cyhalofop, Tolclofos-methyl, Diclomezine, Naproanilide, Bensultap, Dicofol, Folpet, Chlorothalonil, Tebufenozide, Fluthiacet, Milbemectin, Fenoxaprop, Tolylfluanid, Isoxaben, Proquinazid, Ziram, Fluazifop, Cyhexatin, Chinomethionat, Chlorantraniliprole, Chlorpyrifos, Thdemorph, Chromafenozide, Fluquinconazole, Abamectin, Dichlofluanid, Dithiopyr, Aclonifen, Phosalone, Pyridate, Phoxim, Haloxyfop, Oryzalin, Imibenconazole, Flumioxazin, Pyriftalid, Phenmedipham, Fludioxonil, Carpropamid, Isoxathion, Pyraclostrobin, Ethion, Kresoxim-nnethyl, Metiram, Benomyl, Bifenazate, Mepanipyrim, MCPA-thioethyl, Fluoxastrobin, Fentrazamide, Tebufenpyrad, Procymidone, Cafenstrole, Thiazopyr, Phthalide, Nitrothal-isopropyl, Lenacil, Flusulfamide, Fluopicolide, Picoxystrobin, Quizalofop-P-tefuryl, Beflubutamid, Methoxyfenozide, Vinclozolin, Pyribenzoxim, Bromobutide, Fenbuconazole, Fipronil, Bitertanol, Mefenacet, Clodinafop, Diniconazole, Triallate, Fenthion, Mandipropamid, Pyrazophos, Dimoxystrobin, Fenpropimorph, Terbufos, Azinphos-methyl, Boscalid, Ethaboxam, Esprocarb, Simazine, Captan, Profoxydim, Tralkoxydim, Isoxaflutole, Mancozeb, Diclosulam, Cyclosulfamuron, Terbuthylazine, Azoxystrobin, Imazosulfuron, Ipconazole, Desmedipham, Epoxiconazole, Penthiopyrad, Thifluzamide,

Acibenzolar, Fenamidone, Fenoxycarb, Carbendazim, Flutolanil, Benfuracarb, Uniconazole, Lindane, Propazine, Propyzamide, Trifohne, Fentin, Carbaryl, Thticonazole, Butafenacil, Bacillus thuringiensis, Propineb, Zineb, Triflumizole, Flurtamone, Thenylchlor, Pirimiphos-methyl, Phenthoate, Flamprop-M, Iprodione, Halofenozide, Mepronil, Cyprodinil, Bupirimate, Benthiavalicarb, Prosulfocarb, Anilofos, Fenarimol, Tecloftalam, Pyrazosulfuron, Dichlobenil, Difenoconazole, Phosmet, Thiram, Thiobencarb, Indanofan, Quinalphos, Iprovalicarb, Hexaconazole, Fenitrothion, Butachlor, Dimepiperate, Alanycarb, Spinetoram, Fenhexamid, Thiophanate, Thidiazuron, Quinoclamine, Carfentrazone, Terbutryn, Thiodicarb, Imazalil, Emamectin benzoate, Disulfoton, Nuarimol, Diethofencarb, Methiocarb, Profenofos, Benalaxyl, Spirotetramat, Benzoximate, Fenothiocarb, Thiabendazole, Metconazole, Prometryn, Pyraclofos, Diflumetorim, Norflurazon, Prochloraz, Atrazine, Thazophos, Flurochlohdone, Diuron, Tebuconazole, Bromuconazole, Flusilazole, Cyclanilide, Ethofumesate, Ethametsulfuron, Pretilachlor, Fomesafen, Phorate, Cycloxydim, Isoprothiolane, Parath ion-methyl, Flufenacet, Edifenphos, Simeconazole, Methabenzthiazuron, Diazinon, Cinmethylin, Linuron, Bensulfuron, Primisulfuron, Sulfometuron, Triadimefon, Isoproturon, Fubehdazole, Triadimenol, Penconazole, Chlorotoluron, Napropamide, Orysastrobin, Oxpoconazole, Bromoxynil, Cyproconazole, Pyridaphenthion, Dodemorph, Fluometuron, Flucetosulfuron, Etridiazole, Pyrimethanil, Myclobutanil, Metominostrobin, Flutriafol, Carboxin, Malathion, Propiconazole, Tetraconazole, Mesotrione, Prohexadione, Maneb, Cloransulam, Thiacloprid, Metaldehyde, Pinoxaden, and Ametryn. It is envisaged that these materials may be formulated as described in the present specification.

Manufacturing Process (polymer)

The modification of the polymer can be accomplished by a range of known processes. For example in the manufacture of modified PVOH, an acidic solution of PVOH (preferably formed at a temperature of above 80 Celsius) is reacted at around 70 Celsius with an aldehyde/acetal (preferably added dropwise). After the addition of the components the reaction is allowed to proceed for several hours at STP. However, suitable polymer materials are commercially available and include Mowiflex™ LPFX 416 (ex Kuraray).

Particularly preferred embodiments of the present invention are main wash detergent compositions comprising an anionic surfactant. The surfactants are preferably present in the composition at a level of from 1 % to 60% by weight. Suitable anionic surfactants are well known to the person skilled in the art and include alkyl benzene sulphonate, primary and secondary alkyl sulphates, particularly C₈-Ci₅ primary alkyl sulphates; alkyl ether sulphates; olefin sulphonates; alkyl xylene sulphonates, dialkyl sulphosuccinates; ether carboxylates; isethionates; sarcosinates; fatty acid ester sulphonates and mixtures thereof. The sodium salts are generally preferred. When included therein the composition usually contains from about 1 % to about 50%, preferably 10 wt%-40 wt% based on the fabric treatment composition of an anionic surfactant such as linear alkylbenzenesulfonate, alpha-olefinsulfonate, alkyl sulfate (fatty alcohol sulfate), alcohol ethoxysulfate, secondary alkanesulfonate, alpha-sulfo fatty acid methyl ester, alkyl- or alkenylsuccinic acid or soap. Preferred surfactants are alkyl ether sulphates and blends of alkoxylated alkyl nonionic surfactants with either alkyl sulphonates or alkyl ether sulphates. Preferred alkyl ether sulphates are C8-C15 alkyl and have 2-10 moles of ethoxlation. Preferred alkyl sulphates are alkylbenzene sulphonates, particularly linear alkylbenzene sulphonates having an alkyl chain length of Cs-Ci₅. The counter ion for anionic surfactants is typically sodium, although other counter-ions such as TEA or ammonium can be used. Suitable anionic surfactant materials are available in the marketplace as the 'Genapol'™ range from Clariant. In these preferred embodiments the benefit agent is selected from:

a) perfume per se;

b) encapsulated perfume; and,

c) cationic surfactant.

In order that the present invention may be further and better understood it will be illustrated below with reference to particular examples.

Particle Size Measurement

Two methods were employed for measuring particle size.

1. The particles in solution were imaged using a Olympus BX-41 optical microscope fitted with a digital camera. Images were captured using the Olympus Cell P software which allows particle sizes to be measured. 2. The particles were air-dried onto a non-absorbent surface and imaged in a Hitachi TM-1000 desktop scanning electron microscope. The particle size was determined using the length scale added to the image by the associated software.

Examples:

Example 1 : Perfume and Dye as Benefit Agents

1 a) Control solution containing no polymer:

30ml demineralised water

500μl AKK^* perfume + 5μl Oil Red EGN (^*model 15-component perfume)

The perfume, water and Oil Red EGN are mixed using a high-speed stirrer for 20 minutes (1200rpm, Jiffy® stirrer). The temperature is then elevated to 55°C using a water bath and the product is mixed for a further 10 minutes. 10ml of a 20% active solution of linear alkyl benzene sulphonate (LAS) are added. The product is mixed for a further 10 minutes @ 800rpm then allowed to cool to room temperature with stirring over a period of 20 minutes @ 800 rpm.

1 b) Polymer-modified solution:

10ml Mowiflex LPFX 416 (5% active mPVOH ex. Kuraray)

500μl AKK^* perfume + 5μl Oil Red EGN (^*model 15-component perfume) 20ml demineralised water

The perfume, water and Oil Red EGN are mixed using high-speed stirrer for 10 minutes (1200rpm, Jiffy® stirrer). The Mowiflex LPFX 416 is added and stirring continued for a further 10 minutes. The temperature is then elevated to 55°C using a water bath and mixing continued for a further 10 minutes. 10ml of a 20% active solution of linear alkyl benzene sulphonate (LAS) is added and mixing continued for a further 10 minutes @ 800 rpm. The product is allowed to cool to room temperature with stirring over 20 minutes @ 800 rpm.

After 24 hours, the control solution (1a) had a pronounced red layer of free perfume and dye. The solution containing Mowiflex (1 b) was still homogeneous.

Example 2: Perfume and Dye as Benefit Agents

1 ml of the solution prepared in Example (1 b) was dispersed in a 19ml aliquot of un-fragranced detergent base to form product (2a) 1 ml of the solution prepared in Example (1 b) was also dissolved in 19ml of demineralised water to form product (2b).

Both solutions were placed in glass vials, sealed and left at room temperature for 24 hours. After this time, both samples were assessed for the presence of perfume in the headspace.

In the case of (2a), no perfume was detected. In (2b), perfume was detected.

Example 3: Cationic Surfactant as Benefit Agent

(3a) control encapsulate with no polymer

1.75g of Praepagen™ TQ (thethanolamine di-ester quat methosulphate ex

Clariant) was dispersed in 46.5ml of demin water at 50⁰C. The solution was then cooled to 20⁰C and 0.5ml of AKK model perfume added. The solution was then stirred using a high-speed stirrer for 10 minutes. The solution was then warmed to 60°C and stirred for a further 10 minutes. 1.25ml of a 20% linear alkyl benzene sulphonate (LAS) solution was then added and the solution stirrer for a further 10 minutes. The solution was then cooled to 20⁰C and stirred over a further 20 minutes.

(3b) with modified PVOH

The same process was repeated using 42.75ml of demin water, 1.75g Praepagen TQ, 0.5ml of AKK model perfume and 3.75ml of a 5% solution of modified polyvinyl alcohol (Mowiflex™ LPFX 416 ex. Kuraray).

On preparation of the control solution (3a), extensive flocculation was observed when the LAS was added, indicating that an insoluble complex had formed between the LAS and the Praepagen TQ as expected.

However, when the solution (3b) containing the modified PVOH was prepared, no flocculation was observed, indicating that the perfume/Praepagen TQ droplets were protected from the anionic surfactant by the Mowiflex shell. Example 4: Perfume Encapsulates as Benefit Agent

As in example 3 but the Praepagen TQ was replaced with cationically-modified perfume encaps (Coolwear™ ex. Firmenich).

On completion, the solution containing the modified PVOH was translucent with clearly dispersed encapsulates visible under light microscopy. The control solution was opaque with few encaps. After 24 hours, the control solution exhibited both sedimentation and creaming, neither of which was present in the solution containing the modified PVOH.

As in example 3, the presence of the modified PVOH effectively screens the cationic charge on the encapsulate from the anionic surfactant, thus making it stable in anionic-hch detergent products.

Example 5: Dye as Benefit Agent is a Range of Products

In these examples the benefit agent selected was Solvent Violet 13, a cosmetic grade hydrophobic dye, which is suitable for use as a fabric shading agent. The dye (0.1 g) was mixed with 10ml of mineral oil (white, light, ex Sigma Aldrich, CAS No. 8042-47-5) until fully dissolved.

Product samples comprising encapsulated SV13, were obtained as follows: 50OuI of oil/SV13 was dispersed in 50ml of demin water using a Jiffy stirrer @ 1200rpm for 10 minutes. The solution was then heated to 50⁰C, 10ml of 20% LAS solution was added and the stirring speed reduced to 800rpm. After 3 minutes, the solution was cooled to 20⁰C with stirring at 800rpm. Product samples comprising encapsulated SV13 were obtained as follows: 50OuI of oil/SV13 was dispersed in 32ml of demin water using a Jiffy stirrer @ 1200rpm for 5 minutes. 18ml of a 5% solution if Mowiflex LPFX416 was then added and the solution stirred for a further 5 minutes. The solution was then heated to 50⁰C, 10ml of 20% LAS solution was added and the stirring speed reduced to 800rpm. After 3 minutes, the solution was cooled to 20⁰C with stirring at 800rpm.

To test whether or not the dye had been successfully encapsulated, 3ml of each of the solutions was added to 10ml of a commercially available surfactant- containing product. The reflectance spectra of the solution was then measured by filling a 1 cm PMMA cuvette with the solution, covering three sides with white paper and the placing the open face against the apeture of a Color i7 spectrophotometer (6mm apeture plate, specular excluded, UV excluded). A larger -b^* value indicates that more dye has been released into the product.

It can be seen that in all of the examples 5a-5f the encapsulation of the dye significantly reduced the extent to which the dye coloured the bulk of the product.

Claims

1. A composition comprising, 1 -99%wt of surfactant and at least one micro- particle having a diameter of 100nm-2mm, said micro-particle comprising:

i) a core comprising a hydrophobic benefit agent, and,

ii) a shell comprising an uncharged hydrophobically-modified, water- soluble film-forming polymer, whereby the film remains substantially intact in the presence of surfactant but dissolves when the concentration of surfactant is reduced, thereby releasing the benefit agent

2. A composition according to claim 1 wherein the or each particle has a diameter of 1-1000 microns, preferably 1 -100 microns, most preferably

1 -50 microns.

3. A composition according to any preceding claim wherein the backbone of the film-forming polymer is selected from the group consisting of: polyvinyl alcohol, polyvinyl acetate, cellulose ethers, polyethylene oxide, starch, polyvinylpyrrolidone, polyacrylamide, polyvinyl methyl ether-maleic anhydride, polymaleic anhydride, styrene maleic anhydride, hydroxyethylcellulose, methylcellulose, polyethylene glycols, carboxymethylcellulose, polyacrylic acid salts, alginates, acrylamide copolymers, guar gum, casein, ethylene-maleic anhydride resin series, polyethyleneimine, ethyl hydroxyethylcellulose, ethyl methylcellulose, hydroxyethyl methylcellulose, and mixtures thereof.

4. A composition according to any preceding claim wherein the hydrophobic modification is obtained by pre-reaction of the film-forming polymer with an acetal or aldehyde.

5. A composition according to any preceding claim wherein the modified polymer has:

a) a solubility or dispersibility at 2O⁰C in water which contains a concentration of one or more anionic/non-ionic or cationic surfactants of greater than 1 g/L of less than 0.5 g per hour, and,

b) a solubility or dispersibility of greater than 0.5 g per hour when the concentration of anionic/non-ionic or cationic surfactant in water is less than 1g/L.

6. A composition according to any preceding claim wherein the modified polymer is derived from polyvinyl alcohol with a molecular weight of from

10kD to 30OkD preferably from 2OkD to 20OkD most preferably from 75kD to 175kD.

7. A composition according to any preceding claim wherein the modified polymer is derived from polyvinyl alcohol with a hydrolysis range of from 60-99%.

8. A composition according to any preceding claim wherein the modified polymer is derived from polyvinyl alcohol and has a viscosity as a 4% solution within the range 1 to 100 mPa.s at 20⁰C measured according to DIN 053 015.

9. A composition according to any preceding claim wherein the polymer is modified with a hydrophobic, derivatising group which is derived from a parent material having a ClogP of greater than 0.5.

10. A composition according to any preceding claim wherein the parent material for the hydrophobic, derivatising group is selected from the group comprising: butyraldehyde, octyl aldehyde, dodecyl aldehyde, 2-ethyl hexanal, cyclohexane carboxy-aldehyde, citral, propionaldehyde, (2-methoxyethoxy) acetaldehyde dimethylacetal, and benzaldehyde,

11. A composition according to any preceding claim wherein the surfactant is selected from anionic detersive surfactant or cationic surfactant which is a conditioning softening active.

12 A composition according to any preceding claim wherein benefit agent comprises a perfume.

13. A process for treatment of surfaces comprising the step of contacting a composition according to any of claims 1 -12 with fabric, hair or living tissue.

14. A method for preparing compositions according to claims 1 -13 which comprises the steps of:

a) providing an aqueous solution of uncharged, hydrophobically- modified, film forming polymer having a hydrophobic benefit agent dispersed therein,

b) forming a layer of the uncharged, hydrophobically-modified, film forming polymer around the dispersed hydrophobic benefit agent, and

stabilizing said layer with surfactant.