EP2791303A1 - Fabric treatment - Google Patents

Abstract

Use of a particle having a particle size in the range of from 10 nm to 1000 μm, wherein the particle comprises a polymer shell and a core; wherein the core comprises a phase change active, which is a material having a thermal phase transition temperature in the range 24 to 39°C to provide in-wear freshness on sweating, selected from fresh smell, perfume intensity and mixtures thereof, to the wearer of treated garments, wherein the particle is a component of a composition comprising a perfume.

Description

FABRIC TREATMENT

Technical Field The present invention relates to a use of a so-called "phase change active", which is a material having a thermal phase transition temperature in the range of from 24 to 39°C, to impart in-wear freshness on sweating, including fresh smell and perfume intensity, to the wearer of treated fabric. Background and Prior Art

On hot days and in hot climates and under humid conditions people can start to perspire excessively whilst going about their everyday lives. The effect of heat and humidity on the in-wear experience of their clothes can lead to loss of freshness and the perception of malodour due to perspiration. We have now discovered that freshness is a specific need during sweating.

WO03/014460 discloses a composition having a phase transition material that provides a temperature control benefit. The composition is directly applied to a consumer-treatable surface, including a hard surface such as walls, floors, ceilings, a soft surface including clothes, shoes, gloves, socks, curtains and human or animal skin and dried. Also, there is no messiness feeling when a phase change transition of the phase transition material occurs, preferably, also when the composition is directly applied to the consumer treatable surface. If the composition is in a liquid/gel form, it is dried before a phase transition occurs. The temperature control benefit can noticeably increase or decrease the temperature of the climate around the surface, so as to make the climate more comfortable. WO 2007022589 discloses methods and combinations for relieving or preventing the effects of stress, particularly the effects of chronic exposure to stress, comprising exposing a subject to a combination of scents. Compositions containing the combination of scents (specifically cw-3-hexen-l-ol, trans -2- hexenal and a-pinene) and articles impregnated with or including the combination of scents are also disclosed. The composition may be a cleaning composition, a personal hygiene composition, a massage oil, a laundry detergent, a furniture polish, a shoe polish, a cosmetic product, an air freshener, a fragrance

composition, an ink composition, an adhesive composition or a coating composition.

Our related European patent number EP07821655 discloses the use of a fabric softening composition comprising a fabric softening compound and a material having a thermal phase transition temperature in the range 24 to 39°C to impart a cool feel to a fabric.

It has now been found that it is possible to impart freshness on sweating to the wearer of treated garments by the use of a material having a thermal phase transition temperature in the range 24 to 39°C (hereinafter phase change active) in the treatment of the garments.

Summary of the Invention

According to a first aspect of the invention there is provided the use of a particle having a particle size in the range of from 10 nm to 1000 μητι, wherein the particle comprises a polymer shell and a core; wherein the core comprises a phase change active, which is a material having a thermal phase transition temperature in the range 24 to 39°C to provide in-wear freshness on sweating, selected from fresh smell, perfume intensity and mixtures thereof, to the wearer of treated garments, wherein the particle is a component of a composition comprising a perfume.

A laundry composition provides a convenient mode of delivery for the material having a thermal phase transition temperature in the range 24 to 39°C to provide the use of the first aspect of the invention.

Detailed Description of the Invention Phase change active

Phase change actives are materials that can absorb, store and release heat whilst the material changes its physical form. This is known as a phase change. Water changing from solid (ice) to liquid is an example of this phenomenon. During these phase changes large amounts of heat are absorbed or released.

The phase change active has a thermal phase transition temperature (TPTT) in the range 24 to 39°C. The TPTT may conveniently be measured by the Perkin & Elmer thermal analysis system.

The Perkin & Elmer thermal analysis system measures the heat flow into a material to be heated as a function of the temperature of the material. By investigating a material at various temperatures, a temperature profile is obtained. Such a temperature profile usually has one or more peaks, each peak

corresponding to a maximum for the heat flow into the material at a specific temperature. The temperature corresponding to the major peak in the

temperature profile is referred to as the thermal phase transition temperature. Generally a high TPTT corresponds to a high softening temperature of the material. The material has a TPTT in the range 24 to 39°C, preferably from 25 to 39°C, more preferably from 26 to 38°C and most preferably from 26 to 30°C.

Phase change actives possess a latent heat and show a phase transition phenomena between phases at a phase transition temperature. The phase transition of the present invention incorporated solid to liquid, liquid to vapor, solid to vapor, gel to liquid-crystalline phase changes. In the present invention, preferable phase transitions are solid to liquid phase or liquid to solid phase changes. At these phase changes, PTMs reversibly absorb or release heat from the environment at around the phase transition temperature, which is

accompanied with a corresponding change in the ambient temperature.

The phase change active may be in the form of a composition (or mixture) provided that the total composition has a TPTT in the range 24 to 39°C, preferably from 25 to 39°C, more preferably from 26 to 38°C and most preferably from 26 to 30°C.

Suitable compositions may comprise hydrocarbon materials comprising a linear or branched alkyl chain and preferably comprising an average of from 12 to 50 carbon atoms per molecule, preferably from 12 to 30 carbon atoms. Preferably, the hydrocarbon materials are either alkanes or alkenes. Relatively small amounts of non-alkyl substituent groups may be present provided the

hydrocarbon nature of the product is not substantially affected. Mixtures of these materials may be used.

Examples of suitable hydrocarbon materials for use in the hydrocarbon

composition are the liquid hydrocarbon materials of natural source. Other liquid hydrocarbon materials including the liquid fractions derived from crude oil, such as mineral oil, liquid paraffins, cracked hydrocarbons and mixtures thereof. A preferred material is paraffin wax (n-Octadecane).

Examples of solid or semi-solid hydrocarbon materials are the paraffinic materials of longer chain length, and hydrogenated versions of some of the liquid materials mentioned above.

A particularly useful combination of hydrocarbon materials is a mixture of mineral oil (for example, M85 ex Daltons Company) and petroleum jelly (for example, Silkolene 910 ex Daltons), wherein the weight ratio of mineral oil to petroleum jelly is chosen such that the TPTT of the mixture is in the range of from 24 to 39 °C. In our experiments this result was obtained by using a ratio of mineral oil to petroleum jelly of less than 3:1 , preferably from 2:1 to 1 :3. The mineral oil was a liquid mixture of linear and branched hydrocarbons having an average number of carbon atoms per molecule of 26. Petroleum jelly was a semi-solid mixture of linear and branched hydrocarbons having an average number of carbon atoms per molecule of 26, and having a softening temperature of about 50°C.

Encapsulated phase change active comprises a capsule and a phase change active. The capsule comprises a shell and a core. The capsule for the phase change material preferably has a shell that is permeable to the unconfined volatile benefit agent in the composition. A mixture of encapsulated phase change actives may be present. The phase change active may be encapsulated in a polymer shell to form encapsulated particles having a preferred particle size of from 10 nm to 1000 μιτι, preferably 50 nm to 100 μιτι, more preferably 0.2 to 30 μιτι. The use of encapsulated materials has the advantage that the materials may be readily dispersed without interference or interaction with the fabric softener compound. An additional advantage in that the encapsulated material does not cause a "messiness" feeling when deposited on the fabric which may be present with materials of a semi-liquid nature.

Suitable encapsulating polymers include those formed from melamine- formaldehyde or urea formaldehyde condensates, as well as similar types of aminoplasts. Additionally, capsules made via the simple or complex coacervation of gelatin are also preferred for use with the coating. Capsules having shell walls comprised of polyurethane, polyamide, polyolefin, polysaccaharide, protein, silicone, lipid, modified cellulose, gums, polyacrylate, polyphosphate, polystyrene, and polyesters or combinations of these materials are also functional.

Further examples of suitable phase change actives are those materials disclosed in WO 03/0144460 having a phase transition temperature of from 24 to 39 °C, referred to therein as "Phase Transition Materials" or "PTM's" at page 6, final paragraph to the penultimate line on page 8.

A preferred material is Lurapret TX PMC 28 commercially available from BASF which is a material, specifically paraffin wax (comprising n-Octadecane), encapsulated in polymethylmethacrylate having a particle size in the range 0.2 to 20μηη. This material has a phase transition temperature of about 28°C.

The phase change actives are generally deposited to apply from 0.2 to 1 %, preferably 0.2 to 0.5 % by weight of the fabric after drying. The encapsulated phase change actives are generally present in an amount of from 0.01 to 50 wt %, preferably 0.5 to 25 wt %, for example from 5 to 15 wt % by weight of the fabric softening composition. A particularly preferred embodiment contains an amount of from 0.01 to 15 wt %, more preferably 0.01 to 10 wt %, even more preferably from 0.05 to 5 wt %, still more preferably from 0.05 to 2 wt %, more preferably still from 0.05 to 1 wt % and most preferably from 0.05 to 0.5 wt % by weight of the fabric softening composition. Encapsulated phase change material comprises a shell that is permeable to the unconfined volatile benefit agent in the composition. Suitable encapsulating polymers include those formed from melamine-formaldehyde or urea

formaldehyde condensates, as well as similar types of aminoplasts. Additionally, capsules made via the simple or complex coacervation of gelatin are also preferred for use with the coating. Capsules having shell walls comprised of polyurethane, polyamide, polyolefin, polysaccaharide, protein, silicone, lipid, modified cellulose, gums, polyacrylate, polyphosphate, polystyrene, and polyesters or combinations of these materials are also suitable. A preferred material is polymethylmethacrylate.

Compositions

The use of the invention is preferably as a treatment applied by consumers in the home. The treatment may be applied directly to the fabric, e.g. as a spray, or via a laundry product, such as a detergent composition and a fabric conditioner composition. The composition for use in the present invention is preferably a liquid.

The laundry product will contain an active ingredient, which is preferably a surface active agent or a fabric conditioning agent. More than one active ingredient may be included. For some applications a mixture of active ingredients may be used.

The detergent compositions for use in the invention may contain a surface-active compound (surfactant) which may be chosen from soap and non-soap anionic, cationic, non-ionic, amphoteric and zwitterionic surface-active compounds and mixtures thereof. Many suitable surface-active compounds are available and are fully described in the literature, for example, in "Surface-Active Agents and

Detergents", Volumes I and II, by Schwartz, Perry and Berch. The preferred detergent-active compounds that can be used are soaps and synthetic non-soap anionic and non-ionic compounds.

The detergent compositions for use in the invention may contain linear

alkylbenzene sulphonate, particularly linear alkylbenzene sulphonates having an alkyl chain length of Cs-Ci₅. It is preferred if the level of linear alkylbenzene sulphonate is from 0 wt% to 30 wt%, more preferably 1 wt% to 25 wt%, most preferably from 2 wt% to 15 wt%.

The compositions for use the invention may contain other anionic surfactants in amounts additional to the percentages quoted above. Suitable anionic surfactants are well-known to those skilled in the art. Examples include primary and

secondary alkyl sulphates, particularly Cs-Cis primary alkyl sulphates; alkyl ether sulphates; olefin sulphonates; alkyl xylene sulphonates; dialkyl sulphosuccinates; and fatty acid ester sulphonates. Sodium salts are generally preferred.

The compositions for use in the invention may also contain non-ionic surfactant. Nonionic surfactants that may be used include the primary and secondary alcohol ethoxylates, especially the C8-C20 aliphatic alcohols ethoxylated with an average of from 1 to 20 moles of ethylene oxide per mole of alcohol, and more especially the C10-C15 primary and secondary aliphatic alcohols ethoxylated with an average of from 1 to 10 moles of ethylene oxide per mole of alcohol. Non-ethoxylated nonionic surfactants include alkyl-polyglycosides, glycerol monoethers, and polyhydroxyamides (glucamide). It is preferred if the level of nonionic surfactant is from 0 wt% to 30 wt%, preferably from 1 wt% to 25 wt%, most preferably from 2 wt% to 15 wt%.

Fabric Softening Compound

The particle for use in the present invention is preferably a component of a laundry composition. The laundry composition is preferably a fabric conditioner. The fabric conditioner preferably comprises a fabric softening active. The fabric softening active is preferably different from the phase change active. Suitable fabric softening compounds are described below.

The fabric conditioning agents (also referred to herein as a fabric softening active or compound) may be cationic or non-ionic.

Fabric conditioning compositions for use in accordance with the invention may be dilute or concentrated. Dilute products typically contain up to about 8 %, generally about 2 to 8 % by weight of softening active, whereas concentrated products may contain up to about 50 wt %, preferably from about 8 to about 50 %, more preferably from 8 to 25 % by weight active. Overall, the products of the invention may contain from 2 to 50 wt %, preferably from 3 to 25 wt % of softening active.

The preferred softening active for use in rinse conditioner compositions of the invention is a quaternary ammonium compound (QAC). The preferred quaternary ammonium fabric conditioner for use in compositions of the present invention are the so called "ester quats". Particularly preferred materials are the ester-linked triethanolamine (TEA) quaternary ammonium compounds comprising a mixture of mono-, di- and tri- ester linked components. Typically, TEA-based fabric softening compounds comprise a mixture of mono, di- and tri-ester forms of the compound where the di-ester linked component comprises no more than 70 % by weight of the fabric softening compound, preferably no more than 60 wt % of the fabric softening compound and at least 10 % of the monoester linked component.

A first group of quaternary ammonium compounds (QACs) suitable for use in the present invention is represented by formula (I):

[(CH₂)_n(TR)]_m

I

R¹-N⁺-[(CH₂)n(OH)]_3-m X- (I) wherein each R is independently selected from a C_5-3₅ alkyl or alkenyl group; R¹ represents a Ci_-4 alkyl, C2_-4 alkenyl or a Ci_-4 hydroxyalkyl group; T is generally O- CO. (i.e. an ester group bound to R via its carbon atom), but may alternatively be CO-O (i.e. an ester group bound to R via its oxygen atom); n is a number selected from 1 to 4; m is a number selected from 1 , 2, or 3; and X^" is an anionic counter- ion, such as a halide or alkyl sulphate, e.g. chloride or methylsulphate. Di-esters variants of formula I (i.e. m = 2) are preferred and typically have mono- and tri- ester analogues associated with them. Such materials are particularly suitable for use in the present invention.

Especially preferred agents are preparations which are rich in the di-esters of triethanolammonium methylsulphate, otherwise referred to as "TEA ester quats". Commercial examples include Stepantex™ UL85, ex Stepan, Prapagen™ TQL, ex Clariant, and Tetranyl™ AHT-1 , ex Kao, (both di-[hardened tallow ester] of triethanolammonium methylsulphate), AT-1 (di-[tallow ester] of

triethanolammonium methylsulphate), and L5/90 (di-[palm ester] of

triethanolammonium methylsulphate), both ex Kao, and Rewoquat™ WE15 (a di- ester of triethanolammonium methylsulphate having fatty acyl residues deriving from C10-C20 and C16-C18 unsaturated fatty acids), ex Witco Corporation. Also, soft quaternary ammonium actives such as Stepantex VK90, Stepantex VT90, SP88 (ex-Stepan), Prapagen TQ (ex-Clariant), Dehyquart AU-57 (ex- Cognis), Rewoquat WE18 (ex-Degussa) and Tetranyl L190 P, Tetranyl L190 SP and Tetranyl L190 S (all ex-Kao) are suitable. A second group of QACs suitable for use in the invention is represented by formula (II):

(R¹)₃N⁺-(CH₂)_n-CH-TR² X^" (II)

I CH₂TR² wherein each R¹ group is independently selected from Ci_-4 alkyl, hydroxyalkyl or C2_-4 alkenyl groups; and wherein each R² group is independently selected from Cs- 28 alkyl or alkenyl groups; and wherein n, T, and X^" are as defined above.

Preferred materials of this second group include 1 ,2 £>/s[tallowoyloxy]-3- trimethylammonium propane chloride, 1 ,2 £>/s[hardened tallowoyloxy]-3- trimethylammonium propane chloride, 1 ,2-i /s[oleoyloxy]-3-trimethylammonium propane chloride, and 1 ,2 i /s[stearoyloxy]-3-trimethylammonium propane chloride. Such materials are described in US 4,137,180 (Lever Brothers).

Preferably, these materials also comprise an amount of the corresponding mono- ester. A third group of QACs suitable for use in the invention is represented by formula (III):

(R¹ )2-N⁺-[(CH₂)n-T-R²]₂ X^" (III) wherein each R¹ group is independently selected from Ci_-4 alkyl, or C2_-4 alkenyl groups; and wherein each R² group is independently selected from Cs-28 alkyl or alkenyl groups; and n, T, and X^" are as defined above. Preferred materials of this third group include bis(2-tallowoyloxyethyl)dimethyl ammonium chloride, partially hardened and hardened versions thereof.

The iodine value of the quaternary ammonium fabric conditioning material is preferably from 0 to 80, more preferably from 0 to 60, and most preferably from 0 to 45. The iodine value may be chosen as appropriate. Essentially saturated material having an iodine value of from 0 to 5, preferably from 0 to 1 may be used in the compositions of the invention. Such materials are known as "hardened" quaternary ammonium compounds.

A further preferred range of iodine values is from 20 to 60, preferably 25 to 50, more preferably from 30 to 45. A material of this type is a "soft" triethanolamine quaternary ammonium compound, preferably triethanolamine di-alkylester methylsulphate. Such ester-linked triethanolamine quaternary ammonium compound comprises unsaturated fatty chains. lodine value as used in the context of the present invention refers to the measurement of the degree of unsaturation present in a material by a method of nmr spectroscopy as described in Anal. Chem., 34, 1 136 (1962) Johnson and Shoolery.

A further type of softening compound is a non-ester quaternary ammonium material represented by formula (IV):-

wherein each R¹ group is independently selected from Ci_-4 alkyl, hydroxyalkyl or C2_-4 alkenyl groups; R² group is independently selected from Cs-28 alkyl or alkenyl groups, and X^" is as defined above. Oily sugar derivatives

The compositions for use in the invention may contain a non-cationic softening material, which is preferably an oily sugar derivative. An oily sugar derivative is a liquid or soft solid derivative of a cyclic polyol (CPE) or of a reduced saccharide (RSE), said derivative resulting from 35 to 100 % of the hydroxyl groups in said polyol or in said saccharide being esterified or etherified. The derivative has two or more ester or ether groups independently attached to a C8-C22 alkyl or alkenyl chain. Advantageously, the CPE or RSE does not have any substantial crystalline character at 20°C. Instead it is preferably in a liquid or soft solid state as herein defined at 20°C. The liquid or soft solid (as hereinafter defined) CPEs or RSEs suitable for use in the present invention result from 35 to 100% of the hydroxyl groups of the starting cyclic polyol or reduced saccharide being esterified or etherified with groups such that the CPEs or RSEs are in the required liquid or soft solid state. These groups typically contain unsaturation, branching or mixed chain lengths.

Typically the CPEs or RSEs have 3 or more ester or ether groups or mixtures thereof, for example 3 to 8, especially 3 to 5. It is preferred if two or more of the ester or ether groups of the CPE or RSE are independently of one another attached to a Cs to C22 alkyi or alkenyl chain. The Cs to C22 alkyi or alkenyl groups may be branched or linear carbon chains.

Preferably 35 to 85 % of the hydroxyl groups, most preferably 40-80 %, even more preferably 45-75 %, such as 45-70 % are esterified or etherified. Preferably the CPE or RSE contains at least 35 % tri or higher esters, e.g. at least 40 %.

The CPE or RSE has at least one of the chains independently attached to the ester or ether groups having at least one unsaturated bond. This provides a cost effective way of making the CPE or RSE a liquid or a soft solid. It is preferred if predominantly unsaturated fatty chains, derived from, for example, rape oil, cotton seed oil, soybean oil, oleic, tallow, palmitoleic, linoleic, erucic or other sources of unsaturated vegetable fatty acids, are attached to the ester/ether groups. These chains are referred to below as the ester or ether chains (of the CPE or RSE).

The ester or ether chains of the CPE or RSE are preferably predominantly unsaturated. Preferred CPEs or RSEs include sucrose tetratallowate, sucrose tetrarapeate, sucrose tetraoleate, sucrose tetraesters of soybean oil or cotton seed oil, cellobiose tetraoleate, sucrose trioleate, sucrose triapeate, sucrose pentaoleate, sucrose pentarapeate, sucrose hexaoleate, sucrose hexarapeate, sucrose triesters, pentaesters and hexaesters of soybean oil or cotton seed oil, glucose tiroleate, glucose tetraoleate, xylose trioleate, or sucrose tetra-,tri-, penta- or hexa- esters with any mixture of predominantly unsaturated fatty acid chains. The most preferred CPEs or RSEs are those with monounsaturated fatty acid chains, i.e. where any polyunsaturation has been removed by partial

hydrogenation. However some CPEs or RSEs based on polyunsaturated fatty acid chains, e.g. sucrose tetralinoleate, may be used provided most of the polyunsaturation has been removed by partial hydrogenation.

The most highly preferred liquid CPEs or RSEs are any of the above but where the polyunsaturation has been removed through partial hydrogenation.

Preferably 40 % or more of the fatty acid chains contain an unsaturated bond, more preferably 50 % or more, most preferably 60% or more. In most cases 65 % to 100 %, e.g. 65 % to 95 % contain an unsaturated bond. CPEs are preferred for use with the present invention. Inositol is a preferred example of a cyclic polyol. Inositol derivatives are especially preferred.

In the context of the present invention, the term cyclic polyol encompasses all forms of saccharides. Indeed saccharides are especially preferred for use with this invention. Examples of preferred saccharides for the CPEs or RSEs to be derived from are monosaccharides and disaccharides.

Examples of monosaccharides include xylose, arabinose, galactose, fructose, sorbose and glucose. Glucose is especially preferred. Examples of

disaccharides include maltose, lactose, cellobiose and sucrose. Sucrose is especially preferred. An example of a reduced saccharide is sorbitan.

The liquid or soft solid CPEs can be prepared by methods well known to those skilled in the art. These include acylation of the cyclic polyol or reduced

saccharide with an acid chloride; trans-esterification of the cyclic polyol or reduced saccharide fatty acid esters using a variety of catalysts; acylation of the cyclic polyol or reduced saccharide with an acid anhydride and acylation of the cyclic polyol or reduced saccharide with a fatty acid. See for instance US 4 386 213 and AU 14416/88 (both P&G).

It is preferred if the CPE or RSE has 3 or more, preferably 4 or more ester or ether groups. If the CPE is a disaccharide it is preferred if the disaccharide has 3 or more ester or ether groups. Particularly preferred CPEs are esters with a degree of esterification of 3 to 5, for example, sucrose tri, tetra and penta esters.

Where the cyclic polyol is a reducing sugar it is advantageous if each ring of the CPE has one ether or ester group, preferably at the Ci position. Suitable examples of such compounds include methyl glucose derivatives.

Examples of suitable CPEs include esters of alkyl(poly)glucosides, in particular alkyl glucoside esters having a degree of polymerisation of 2. The length of the unsaturated (and saturated if present) chains in the CPE or RSE is C8-C22, preferably Ci2-C22- It is possible to include one or more chains of C Cs, however these are less preferred. The liquid or soft solid CPEs or RSEs which are suitable for use in the present invention are characterised as materials having a solid:liquid ratio of between 50:50 and 0:100 at 20°C as determined by T₂ relaxation time NMR, preferably between 43:57 and 0:100, most preferably between 40:60 and 0:100, such as, 20:80 and 0:100. The T₂ NMR relaxation time is commonly used for

characterising solid:liquid ratios in soft solid products such as fats and margarines. For the purpose of the present invention, any component of the signal with a T₂ of less than 100 με is considered to be a solid component and any component with T₂ > 100 με is considered to be a liquid component. For the CPEs and RSEs, the prefixes (e.g. tetra and penta) only indicate the average degrees of esterification. The compounds exist as a mixture of materials ranging from the monoester to the fully esterified ester. It is the average degree of esterification which is used herein to define the CPEs and RSEs. The HLB of the CPE or RSE is typically between 1 and 3.

Where present, the CPE or RSE is preferably present in the composition in an amount of 0.5-50% by weight, based upon the total weight of the composition, more preferably 1 -30% by weight, such as 2-25%, e.g. 2-20%.

The CPEs and RSEs for use in the compositions of the invention include sucrose tetraoleate, sucrose pentaerucate, sucrose tetraerucate and sucrose pentaoleate. Co-softeners and fatty complexing agents

Co-softeners may be used. When employed, they are typically present at from 0.1 to 20% and particularly at from 0.5 to 10%, based on the total weight of the composition. Preferred co-softeners include fatty esters, and fatty N-oxides. Fatty esters that may be employed include fatty monoesters, such as glycerol monostearate, fatty sugar esters, such as those disclosed WO 01/46361

(Unilever). The compositions for use in the present invention may comprise a fatty

complexing agent.

Especially suitable fatty complexing agents include fatty alcohols and fatty acids. Of these, fatty alcohols are most preferred.

Fatty complexing material may be used to improve the viscosity profile of the composition.

Preferred fatty acids include hardened tallow fatty acid (available under the tradename Pristerene™, ex Uniqema). Preferred fatty alcohols include hardened tallow alcohol (available under the tradenames Stenol™ and Hydrenol™, ex Cognis and La u rex™ CS, ex Albright and Wilson).

The fatty complexing agent is preferably present in an amount greater than 0.3 to 5% by weight based on the total weight of the composition. More preferably, the fatty component is present in an amount of from 0.4 to 4%. The weight ratio of the mono-ester component of the quaternary ammonium fabric softening material to the fatty complexing agent is preferably from 5:1 to 1 :5, more preferably 4:1 to 1 :4, most preferably 3:1 to 1 :3, e.g. 2:1 to 1 :2. Non-ionic surfactant

The compositions for use in the present invention may further comprise a nonionic surfactant. Typically these can be included for the purpose of stabilising the compositions. These are particularly suitable for compositions comprising hardened quaternary ammonium compounds.

Suitable nonionic surfactants include addition products of ethylene oxide and/or propylene oxide with fatty alcohols, fatty acids and fatty amines. Any of the alkoxylated materials of the particular type described hereinafter can be used as the nonionic surfactant.

Suitable surfactants are substantially water soluble surfactants of the general formula:

R-Y-(C₂H₄0)_z-CH₂-CH₂-OH where R is selected from the group consisting of primary, secondary and branched chain alkyl and/or acyl hydrocarbyl groups (when Y = -C(O)O, R≠ an acyl hydrocarbyl group); primary, secondary and branched chain alkenyl hydrocarbyl groups; and primary, secondary and branched chain alkenyl- substituted phenolic hydrocarbyl groups; the hydrocarbyl groups having a chain length of from 8 to about 25, preferably 10 to 20, e.g. 14 to 18 carbon atoms.

In the general formula for the ethoxylated nonionic surfactant, Y is typically:

-O- , -C(O)O- , -C(O)N(R)- or -C(O)N(R)R- in which R has the meaning given above or can be hydrogen; and Z is at least about 8, preferably at least about 10 or 1 1 .

Preferably the nonionic surfactant has an HLB of from about 7 to about 20, more preferably from 10 to 18, e.g. 12 to 16. Genapol™ C200 (Clariant) based on coco chain and 20 EO groups is an example of a suitable nonoionic surfactant.

If present, the nonionic surfactant is present in an amount from 0.01 to 10%, more preferably 0.1 to 5 by weight, based on the total weight of the composition.

Shading Dyes

Optional shading dyes can be used. Preferred dyes are violet or blue. Suitable and preferred classes of dyes are discussed below. Moreover the unsaturated quaternary ammonium compounds are subject to some degree of UV light and/or transition metal ion catalysed radical auto-oxidation, with an attendant risk of yellowing of fabric. The presence of a shading dye also reduces the risk of yellowing from this source. Different shading dyes give different levels of colouring. The level of shading dye present in the compositions of the present invention depend, therefore, on the type of shading dye. Preferred overall ranges, suitable for the present invention are from 0.00001 to 0.1 wt %, more preferably 0.0001 to 0.01 wt %, most preferably 0.0005 to 0.005 wt % by weight of the total composition. Direct Dyes

Direct dyes (otherwise known as substantive dyes) are the class of water soluble dyes which have an affinity for fibres and are taken up directly. Direct violet and direct blue dyes are preferred.

Preferably the dye are bis-azo or tris-azo dyes are used.

Most preferably, the direct dye is a direct violet of the following structures:

wherein:

ring D and E may be independently naphthyl or phenyl as shown;

Ri is selected from: hydrogen and C1 -C4-alkyl, preferably hydrogen;

F¾ is selected from: hydrogen, C1 -C4-alkyl, substituted or unsubstituted phenyl and substituted or unsubstituted naphthyl, preferably phenyl; R3 and R₄ are independently selected from: hydrogen and C1 -C4-alkyl, preferably hydrogen or methyl;

X and Y are independently selected from: hydrogen, C1 -C4-alkyl and C1 -C4- alkoxy; preferably the dye has X= methyl; and, Y = methoxy and n is 0, 1 or 2, preferably 1 or 2.

Preferred dyes are direct violet 7, direct violet 9, direct violet 1 1 , direct violet 26, direct violet 31 , direct violet 35, direct violet 40, direct violet 41 , direct violet 51 , and direct violet 99. Bis-azo copper containing dyes such as direct violet 66 may be used.

The benzidene based dyes are less preferred.

Preferably the direct dye is present at 0.00001 wt% to 0.0010 wt% of the formulation.

In another embodiment the direct dye may be covalently linked to the photo- bleach, for example as described in WO2006/024612. Acid dyes

Cotton substantive acid dyes give benefits to cotton containing garments.

Preferred dyes and mixes of dyes are blue or violet. Preferred acid dyes are: (i) azine dyes, wherein the dye is of the following core structure:

wherein R_a, R_b, R_c and R_d are selected from: H, a branched or linear C1 to C7- alkyl chain, benzyl a phenyl, and a naphthyl;

the dye is substituted with at least one SO3^" or -COO^" group;

the B ring does not carry a negatively charged group or salt thereof;

and the A ring may further substituted to form a naphthyl;

the dye is optionally substituted by groups selected from: amine, methyl, ethyl, hydroxyl, methoxy, ethoxy, phenoxy, CI, Br, I, F, and NO2.

Preferred azine dyes are: acid blue 98, acid violet 50, and acid blue 59, more preferably acid violet 50 and acid blue 98.

Other preferred non-azine acid dyes are acid violet 17, acid black 1 and acid blue 29.

Preferably the acid dye is present at 0.0005 wt% to 0.01 wt% of the formulation. Hydrophobic dyes

The composition for use in the invention may comprise one or more hydrophobic dyes selected from benzodifuranes, methine, triphenylmethanes, napthalimides, pyrazole, napthoquinone, anthraquinone and mono-azo or di-azo dye

chromophores. Hydrophobic dyes are dyes which do not contain any charged water solubilising group. Hydrophobic dyes may be selected from the groups of disperse and solvent dyes. Blue and violet anthraquinone and mono-azo dye are preferred.

Preferred dyes include solvent violet 13, disperse violet 27 disperse violet 26, disperse violet 28, disperse violet 63 and disperse violet 77.

Preferably the hydrophobic dye is present at 0.0001 wt% to 0.005 wt% of the formulation. Basic dyes

Basic dyes are organic dyes which carry a net positive charge. They deposit onto cotton. They are of particular utility for used in composition that contain predominantly cationic surfactants. Dyes may be selected from the basic violet and basic blue dyes listed in the Colour Index International.

Preferred examples include triarylmethane basic dyes, methane basic dye, anthraquinone basic dyes, basic blue 16, basic blue 65, basic blue 66, basic blue 67, basic blue 71 , basic blue 159, basic violet 19, basic violet 35, basic violet 38, basic violet 48; basic blue 3, basic blue 75, basic blue 95, basic blue 122, basic blue 124, basic blue 141 .

Reactive dyes Reactive dyes are dyes which contain an organic group capable of reacting with cellulose and linking the dye to cellulose with a covalent bond. They deposit onto cotton. Preferably the reactive group is hydrolysed or reactive group of the dyes has been reacted with an organic species such as a polymer, so as to the link the dye to this species. Dyes may be selected from the reactive violet and reactive blue dyes listed in the Colour Index International.

Preferred examples include reactive blue 19, reactive blue 163, reactive blue 182 and reactive blue 96.

Dye conjugates

Dye conjugates are formed by binding direct, acid or basic dyes to polymers or particles via physical forces.

Dependent on the choice of polymer or particle they deposit on cotton or synthetics. A description is given in WO2006/055787. They are not preferred.

Particularly preferred dyes are: direct violet 7, direct violet 9, direct violet 1 1 , direct violet 26, direct violet 31 , direct violet 35, direct violet 40, direct violet 41 , direct violet 51 , direct violet 99, acid blue 98, acid violet 50, acid blue 59, acid violet 17, acid black 1 , acid blue 29, solvent violet 13, disperse violet 27 disperse violet 26, disperse violet 28, disperse violet 63, disperse violet 77 and mixtures thereof.

Perfume The compositions for use in the present invention may comprise one or more perfumes if desired. The perfume is preferably present in an amount from 0.01 to 10 % by weight, more preferably from 0.05 to 5 % by weight, even more

preferably from 0.1 to 4.0 %, most preferably from 0.15 to 4.0 % by weight, based on the total weight of the composition. 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 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, 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.

Some or all of the perfume or pro-fragrance may be encapsulated, 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 and pro-fragrances which can produce such components. It is also advantageous to encapsulate perfume components which have a low Clog P (i.e. those which will be partitioned into water), preferably with a Clog P of less than 3.0. These materials, of relatively low boiling point and relatively low Clog P have been called the "delayed blooming" perfume ingredients and include the following materials:

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

Benzaldehyde, Benzyl Acetate, Benzyl Acetone, Benzyl Alcohol, Benzyl Formate, Benzyl Iso 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 (tricyclco Decenyl Propionate), Geraniol, Hexenol, Hexenyl Acetate, Hexyl Acetate, Hexyl Formate, Hydratropic Alcohol, Hydroxycitronellal, Indone, Isoamyl Alcohol, Iso Menthone, Isopulegyl 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.

Preferred non-encapsulated perfume ingredients are those hydrophobic perfume components with a ClogP above 3. As used herein, the term "ClogP" means the re

calculated logarithm to base 10 of the octanol/water partition coefficient (P). The octanol/water partition coefficient of a perfume raw material (PRM) is the ratio between its equilibrium concentrations in octanol and water. Given that this measure is a ratio of the equilibrium concentration of a PRM in a non-polar solvent (octanol) with its concentration in a polar solvent (water), ClogP is also a measure of the hydrophobicity of a material-the higher the ClogP value, the more hydrophobic the material. ClogP values can be readily calculated from a program called "CLOGP" which is available from Daylight Chemical Information Systems Inc., Irvine Calif., USA. Octanol/water partition coefficients are described in more detail in U.S. Pat. No. 5,578,563.

Perfume components with a ClogP above 3 comprise: Iso E super, citronellol, Ethyl cinnamate, Bangalol, 2,4,6-Trimethylbenzaldehyde, Hexyl cinnamic aldehyde, 2,6-Dimethyl-2-heptanol, Diisobutylcarbinol, Ethyl salicylate, Phenethyl isobutyrate, Ethyl hexyl ketone, Propyl amyl ketone, Dibutyl ketone, Heptyl methyl ketone, 4,5-Dihydrotoluene, Caprylic aldehyde, Citral, Geranial, Isopropyl benzoate, Cyclohexanepropionic acid, Campholene aldehyde, Caprylic acid, Caprylic alcohol, Cuminaldehyde, 1 -Ethyl-4-nitrobenzene, Heptyl formate, 4- Isopropylphenol, 2-lsopropylphenol, 3-lsopropylphenol, Allyl disulfide, 4-Methyl-1 - phenyl-2-pentanone, 2-Propylfuran, Allyl caproate, Styrene, Isoeugenyl methyl ether, Indonaphthene, Diethyl suberate, L-Menthone, Menthone racemic, p-Cresyl isobutyrate, Butyl butyrate, Ethyl hexanoate, Propyl valerate, n-Pentyl propanoate, Hexyl acetate, Methyl heptanoate, trans-3,3,5-Trimethylcyclohexanol, 3,3,5- Trimethylcyclohexanol, Ethyl p-anisate, 2-Ethyl-1 -hexanol, Benzyl isobutyrate, 2,5-Dimethylthiophene, Isobutyl 2-butenoate, Caprylnitrile, gamma-Nonalactone, Nerol, trans-Geraniol, 1 -Vinylheptanol, Eucalyptol, 4-Terpinenol, Dihydrocarveol, Ethyl 2-methoxybenzoate, Ethyl cyclohexanecarboxylate, 2-Ethylhexanal, Ethyl amyl carbinol, 2-Octanol, 2-Octanol, Ethyl methylphenylglycidate, Diisobutyl ketone, Coumarone, Propyl isovalerate, Isobutyl butanoate, Isopentyl propanoate, 2-Ethylbutyl acetate, 6-Methyl-tetrahydroquinoline, Eugenyl methyl ether, Ethyl dihydrocinnamate, 3,5-Dimethoxytoluene, Toluene, Ethyl benzoate, n- Butyrophenone, alpha-Terpineol, Methyl 2-methylbenzoate, Methyl 4- methylbenzoate, Methyl 3, methylbenzoate, sec. Butyl n-butyrate, 1 ,4-Cineole, Fenchyl alcohol, Pinanol, cis-2-Pinanol, 2,4, Dimethylacetophenone, Isoeugenol, Safrole, Methyl 2-octynoate, o-Methylanisole, p-Cresyl methyl ether, Ethyl anthranilate, Linalool, Phenyl butyrate, Ethylene glycol dibutyrate, Diethyl phthalate, Phenyl mercaptan, Cumic alcohol, m-Toluquinoline, 6-Methylquinoline, Lepidine, 2-Ethylbenzaldehyde, 4-Ethylbenzaldehyde, o-Ethylphenol, p- Ethylphenol, m-Ethylphenol, (+)-Pulegone, 2,4-Dimethylbenzaldehyde,

Isoxylaldehyde, Ethyl sorbate, Benzyl propionate, 1 ,3-Dimethylbutyl acetate, Isobutyl isobutanoate, 2,6-Xylenol, 2,4-Xylenol, 2,5-Xylenol, 3,5-Xylenol, Methyl cinnamate, Hexyl methyl ether, Benzyl ethyl ether, Methyl salicylate, Butyl propyl ketone, Ethyl amyl ketone, Hexyl methyl ketone, 2,3-Xylenol, 3,4, Xylenol, Cyclopentadenanolide and Phenyl ethyl 2 phenylacetate 2.

It is commonplace for a plurality of perfume components to be present in a formulation. In the compositions for use in 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 and/or the list of perfume components with a ClogP above 3 present in the 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. Further Optional Ingredients

The compositions for use in the invention may contain one or more other ingredients. Such ingredients include further preservatives (e.g. bactericides), pH buffering agents, perfume carriers, hydrotropes, anti-redeposition agents, soil- release agents, polyelectrolytes, anti-shrinking agents, anti-wrinkle agents, antioxidants, sunscreens, anti-corrosion agents, drape imparting agents, anti-static agents, ironing aids, silicones, antifoams, colourants, pearlisers and/or opacifiers, natural oils/extracts, processing aids, eg electrolytes, hygiene agents, eg anti- bacterials and antifungals, thickeners and skin benefit agents.

The Fabric softening compositions may also comprise viscosity modifiers.

Suitable viscosity modifiers are disclosed, for example, in WO 02/08161 1 ,

US 2004/0214736, US 6827795, EP 0501714, US 2003/0104964, EP 0385749 and EP 331237.

Product Form

The compositions for use in the present invention are preferably rinse-added softening compositions.

The compositions have a pH ranging from about 2.5 to 6, preferably from about 2.5 to 4.5, most preferably about 2.5 to 2.8. The compositions for use in the invention may also contain pH modifiers such as hydrochloric acid or lactic acid.

A composition for use in the invention is preferably in liquid form. The

composition may be a concentrate to be diluted in a solvent, including water, before use. The composition may also be a ready-to-use (in-use) composition. Preferably the composition is provided as a ready to use liquid comprising an aqueous phase. The aqueous phase may comprise water-soluble species, such as mineral salts or short chain (Ci_-4) alcohols.

The composition is preferably for use in the rinse cycle of a home textile laundering operation, where, it may be added directly in an undiluted state to a washing machine, e.g. through a dispenser drawer or, for a top-loading washing machine, directly into the drum. Alternatively, it can be diluted prior to use. The compositions may also be used in a domestic hand-washing laundry operation. It is also possible for the compositions of the present invention to be used in industrial laundry operations, e.g. as a finishing agent for softening new clothes prior to sale to consumers.

Preparation Compositions used in the invention can be prepared by any method suitable for preparing dispersed, emulsified systems. One method involves the forming of a molten premixture of the active materials in water at an elevated temperature, adding additional water to obtain the desired active concentration, and then cooling to ambient temperature. When desired, some minor ingredients such as electrolytes, colouring agents, etc. may be post-dosed. A second method involves the forming of the product by phase inversion of a water in hydrocarbon emulsion, wherein the cationic material is either part of the hydrocarbon phase or added as a separate predispersion. This method is advantageous, because this provides very finely divided hydrocarbon particles in the final product. In an alternative method the encapsulated phase change active may be post dosed in the form of an aqueous slurry.

The invention will be illustrated by the following Examples. Examples

Embodiments of the invention will now be illustrated by the following non-limiting examples. Further modifications will be apparent to the person skilled in the art.

Examples of the invention are represented by a number. Comparative examples are represented by a letter.

Unless otherwise stated, amounts of components are expressed as a percentage of the total weight of the composition.

Example 1 :- Preparation and composition of Fabric Conditioner 1 , for use in accordance with the invention, and Comparative Example A. Composition 1 and Comparative Example A were dilute liquid fabric conditioners, comprising 4.5 % of softening active. The compositions are shown in Table 1 .

Table 1 : Connposition of Fabric Conditioner 1 (wt %, based on 100 % active ingredients)

Valm based soft TEA Quat

2Pearlescer, preservative, sequestrant, etc

³Based on 100 % activity Example 2:- Treatment of Garments using Composition 1 and Comparative Example A

Test garments

Black trousers and white tops were used as test garments. Garments for the study were tailor-made for each participant to ensure consistency of garment design and fit across all participants. All test garments were first washed in commercially available washing powder in an automatic washing machine and line dried. The wash conditions were as follows;

Treatment with Composition 1 and Comparative Example A

Garments were added to an automatic washing machine and the rinse cycle selected. 42 g of the fabric conditioner was added to the washing machine drawer. The garments were then line dried. Panel Test Method and Conditions

A blind, unbranded test regime was adopted. The test took place during a hot and humid period in Bangkok and involved 30 participants wearing the test garments all day. Each participant wore garments treated with the comparative example and composition 1 on separate days. Control garments (wash only) were also included. Participants were not asked to compare one set of garments to another. They went about their normal routine of travelling to and from work, having their lunch outdoors, and working indoors in air-conditioned offices at other times. The weather was monitored during the experiment and was found to be relatively consistent, averaging around 32°C/50% RH at midday.

Participants recorded fresh smell as well as perfume intensity levels at the event of onset of sweating .

Statistical analysis was carried out using a repeated measurement model fitted to the data; "repeated" meaning that each participant in the study was measured several times. Such a model incorporates the time and also reflects that there are several layers of random influences present in the way the data was collected. These layers are: the "within participant" variation over time, the "between participant" variation due to different features of the participant and treatment and the overall external random influences and measurement errors. A linear effects model was used to describe the three sources of variability. This model consists of a classical linear model (some function of the controlled and observed influences) and a random effects model. Only after fitting both is the error variance determined. Therefore, the output of the model is a functional description of the population trend and, for each individual, a fit of the deviation from this trend.

The statistics package R (version 3.1 -94) was used for the repeated measurement and linear mixed effects models. The p values shown below indicate Confidence at 95% Significance. The confidence for the perfume intensity was generated from the on-set of sweating event data. Example 3:- Fresh smell and perfume intensity on sweating imparted by garments treated with Composition 1 and Comparative Example A

Table 2: Fresh smell and perfume intensity levels at the onset of sweating for garments treated with comparative example A and Composition 1 .

It will be seen that garments treated in accordance with the invention conferred improved fresh smell and intensity of perfume on sweating to the wearer.

Claims

1 . Use of a particle having a particle size in the range of from 10 nm to

1000 μητι, wherein the particle comprises a polymer shell and a core; wherein the core comprises a phase change active, which is a material having a thermal phase transition temperature in the range 24 to 39°C to provide in- wear freshness on sweating, selected from fresh smell, perfume intensity and mixtures thereof, to the wearer of treated garments, wherein the particle is a component of a composition comprising a perfume.

2. Use as claimed in claim 1 , wherein the particle is a component of a laundry composition.

3. Use as claimed in claim 2 in which the laundry composition is a fabric

conditioner.

4. Use as claimed in claim 2 or claim 3 in which the particle comprising the

phase change active is present in an amount from 0.05 to 50 wt %, preferably 0.5 to 25 wt %, most preferably from 5 to 15 wt % by weight of the

composition.

5. Use as claimed in claim 3 in which the fabric conditioner comprises a fabric conditioning agent selected from an oily sugar derivative, a cationic fabric softening compound and mixture thereof.

6. Use as claimed in claim 5 in which the cationic fabric softening compound is a quaternary ammonium compound having at least two Ci2-28 groups

connected to the nitrogen head group that may independently be alkyl or alkenyl groups, preferably being connected to the nitrogen head group by an ester link.

7. Use as claimed in any one of claims 2 to 6, which additionally comprises one or more ingredients selected from perfume, non-ionic surfactant, fatty acid, fatty alcohol and viscosity modifier.

8. Use as claimed in any preceding claim, wherein the shell comprises

encapsulating polymers selected from melamine-formaldehyde and urea formaldehyde condensates. 9. Use as claimed in any preceding claim, wherein the phase change active comprises hydrocarbon materials comprising a linear or branched alkyl chain and preferably comprising an average of from 12 to 50 carbon atoms per molecule, preferably from 12 to 30 carbon atoms. 10. Use as claimed in any preceding claim, wherein the phase change material comprises a mixture of mineral oil and petroleum jelly and wherein the weight ratio of mineral oil to petroleum jelly is such that the thermal phase transition temperature of the mixture is from 27°C to 38°C. Use as claimed in claim 10, wherein the mineral oil is a liquid mixture of linear and branched hydrocarbons having an average number of carbon atoms per molecule of 26 and the petroleum jelly is a semi-solid mixture of linear and branched hydrocarbons having an average number of carbon atoms per molecule of 26, and having a softening temperature of about 50°C.

Use as claimed in any one of claims 1 to 8, wherein the phase change active is selected from mineral oil, liquid paraffins, cracked hydrocarbons and mixtures thereof.

13. Use as claimed in claim 12, wherein the phase change active is n- octadecane.