GB2349896A

GB2349896A - Delayed release product

Info

Publication number: GB2349896A
Application number: GB9911137A
Authority: GB
Inventors: Helen Elizabeth Herd; Mark Phillip Houghton
Original assignee: ROBERT MCBRIDE GROUP Ltd
Current assignee: ROBERT MCBRIDE GROUP Ltd
Priority date: 1999-05-14
Filing date: 1999-05-14
Publication date: 2000-11-15
Also published as: GB9911137D0

Abstract

A product having delayed release active material is described. The product includes a substrate and encapsulates of a volatile liquid distributed on and/or in the substrate. A barrier composition is present on the substrate to substantially isolate encapsulates distributed on and/or in the said substrate from the surrounding environment. A fabric conditioning composition is also described. The conditioning composition includes a fabric conditioning matrix and encapsulates of active material such as volatile liquid dispersed in the said matrix.

Description

2349896 A PRODUCT HAVING DELAYED RELEASE OF ACTIVE MATERIAL The invention

relates a product having delayed release of active material and also to an indicator system-to alert a user of a disposable product in sheet form that the product has performed its function and / or has exhausted its capacity for releasing an active material. The invention also relates to a process of using such a product.

In particular the invention is considered particularly suitable for a tumble dryer fabric conditioning sheet. Such sheets consist of a porous substrate, an impregnated softening compound and perform their function by being agitated with textiles, usually at elevated temperatures, such as to distribute the impregnated softening material. Such products are highly concentrated and occupy a smaller volume than a liquid conditioner and are widely used.

The process of tumble drying textiles with a conditioner sheet consists of two separate processes. The removal of water by a flow of hot air and the transfer of one or more active compositions from the sheet to the textile. The former process is often the rate determining step and hence the active materials on the sheet will be exposed to hot air flow for an extended period of time relative to that required for their action. This is particularly critical for odiferous compounds which are generally more volatile than water and hence give limited performance in fragrancing the textile. However, typically, such drying machines include a cool air flow for the final minutes of the drying process to allow polyester based garments to fall below their glass transition temperature and hence avoid deformation and creasing.

The use of wipes and tumble dryer sheets is well established. A wide range of substrate materials are also known (US 2228033, 1941, Martone, US 3,301,746,1967, Sanford et al. US 3,414,459, 1968, Wells. US 3,499,316, 1970, Krause, US 3,775,231, 1973, Thomas. US 3,837,996, 1974, Braun et al., US 4,231,370, 1980, Mroz et al..) Various product forms for delivering active materials, typically softeners and anti-static agents in tumble dryers have been disclosed. For example US 3, 634, 947, US 3, 686, 025 and US 3, 442, 692 disclose a fatty alkyl cationic surfactant based product with various methods of application in a dryer.

US 3,936,538 discloses a waxy surfactant softening agent and a film forming polymer added in a tumble dryer. No disclosure of the film forming polymer as an encapsulant or of the softening agent residing predominantly within a protective coating is disclosed.

US 5,783,552 (Trinh) discloses tumble dryer sheets with cyclodextrin 5 impregnation for retention of perfume activity.

U.S. Pat. No. 4,234,627, discloses the microencapsulation of fabric softener which is applied during a washing operation. No disclosure of the fabric softener protecting and coating an encapsulate, rather than being itself encapsulated is disclosed.

According to a first aspect of the present invention there is provided a product having delayed release active material, comprising a substrate and encapsulates of a volatile liquid distributed on and/or in the substrate, wherein a barrier composition is present on the substrate to substantially isolate encapsulates distributed on and/or in the said substrate from the surrounding environment.

According to a second aspect of the present invention there is provided a fabric conditioning composition comprising a fabric conditioning matrix and encapsulates of active material such as volatile liquid dispersed in the said matrix.

According to a third aspect of the present invention there is provided a product having a delayed release active material comprising a substrate and an active material distributed on and/or in the substrate, wherein a barrier composition is present on the substrate to substantially isolate the said active material from the surrounding environment.

The invention extends to any one or more active material known to have a beneficial effect, preferably, in laundry drying applications such as perfumes, colour indicators, cyclic silicones, volatile silicones, polydimethyl silicones, liquid surfactants, bleach precursors, antifoaming agents and/or perfume precursors.

Advantageously, the delayed release of an encapsulated liquid or active material is effected by each of the above aspects of the present invention. By isolating the active material or encapsulant its release may be delayed until removal of the barrier, in use. In the case of the second aspect, the encapsulates may be progressively exposed to the environment as the matrix is depleted thus providing a controlled, progressive release of the active material. A particular application of this second aspect is on substrates in accordance with the first or third aspect but it will be appreciated that it may be used as a liquid fabric conditioner directly.

Preferably, there is also a colour indicator component distributed on and/or in the substrate, wherein the barrier composition is also present on the substrate to substantially isolate colour indicator distributed on and/or in the said substrate from the surrounding environment. Preferably, the barrier composition forms a film or coating on the substrate which is, preferably, substantially continuous across at least one substrate area where material such as active material, encapsulate or indicator is present.

Advantageously, by the use of a barrier composition, the action of the isolated material may be delayed until such time as the barrier is removed at least to the extent that at least some of the previously isolated material is exposed to the environment surrounding the product.

Although it is not essential for the barrier to be coated across all the surface area of the substrate, it is preferred that the barrier composition be so distributed so that substantially all the active material is isolated by the composition.

Preferably the barrier composition is removed from the substrate by contact with other substances or articles.

Preferably, the barrier composition is progressively removed by contact with other substances or articles. Preferably, the barrier composition is liquid, more preferably, the barrier composition is liquid during removal in use.

Preferably, the barrier composition is liquid above 370C. The barrier composition may form a liquid film during use and, typically, be applied to the substrate as solid or liquid by a suitable method known to those skilled in the art such as coating, dipping or spraying.

In one preferred embodiment, the barrier composition is a fabric softener.

The substrate may be any suitable material known to those skilled in the art which will also preferably absorb colour indicator and act as a substrate for the barrier composition and encapsulate and/or other active material.

In one preferred embodiment, the substrate is a tumble dryer sheet of the type used as disposable tumble dryer sheets. The composition is then progressively removed during the drying action to gradually expose the isolated material to the surrounding environment.

In a further embodiment, of the second or third aspect of the invention, an encapsulated volatile liquid may be the active material distributed on and/or in the substrate and isolated by the said barrier composition.

Preferably, the barrier composition is hydrophobic and, in such cases, the isolated material is water sensitive. A hydrophobic coating is particularly advantageous where the isolated material is water sensitive. In this way water transfer across the barrier is prevented 10 either from the isolated material to the surrounding environment or from the surrounding environment to the isolated material. Preferably, the encapsulant comprises a protective encapsulating layer and active material held within the encapsulating layer. 15 Preferably, the protective encapsulating layer integrity is sensitive to the environment, in use, causing release of the active material. Preferably, the encapsulating layer integrity is dependent upon one or more 20 components present in the layer which may be lost or chemically changed in a suitable environment to cause the integrity of the layer to be lost, thus facilitating release of the active material. The integrity of the encapsulating layer may be sensitive to the loss or gain of a volatile component. Preferably, the encapsulating layer is sensitive to water gain and/or water loss, most 25 preferably, water loss and, in any case, to the extent that the integrity of the layer is lost as a result of such sensitivity. In the same way, the encapsulating layer may be sensitive to physical conditions such as temperature or pressure. The barrier composition layer is preferably 10 to 1000,4m thick, more 30 preferably from 20 to 20OAm thick most preferably between 100 and 150/Am thick on average and, preferably, the encapsulate is covered to these depths. These can be determined by microscopy. In one preferred embodiment, the isolated material is sensitive to water loss. 35 Such an isolated material, in particular, the encapsulant, may be used for tumble dryer applications. In such an embodiment, the barrier composition is progressively removed in use by contact with the dryer load until the encapsulant is directly exposed to the atmosphere in the dryer, resulting in loss of water or other volatile component from the protective layer of the 40 encapsulant and a resultant fragrance release. Such a fragrance release thus indicates that the softener has been exhausted and the cycle is complete.

In another embodiment, the barrier composition is hydrophobic and the isolated material such as encapsulant is sensitive to water gain. Such a combination could be used for a moisturising wipe where the hydrophobic coating is an emollient such as skin cream or the like. Exposure to water from the skin or the general environment will cause the encapsulant to absorb moisture and cause a fragrance release to accompany the hydrophobic coating use.

In a still further embodiment, other components are isolated by the composition such as indicator components which are thereby released once the barrier composition has been at least partially removed. This may take place directly or as a result of a secondary action due to exposure of the indicator component to water, heat, etc in the general environment or by contact with an external substance.

A binder may be utilised to bind the isolated material to the substrate. Similarly, suitable binders may be used to bind any of the other components to the substrate although it is preferred that the barrier composition is self adhering to the substrate, at least in use.

According to a fourth aspect of the present invention, there is provided a method of producing a delayed release encapsulant product comprising the steps of:- (a) distributing an encapsulant containing a volatile liquid component on and/or in a substrate; (b) adding a barrier composition to the substrate to substantially isolate the encapsulant distributed on and/or in the said substrate from the surrounding environment.

Preferably, a colour indicator is distributed on and/or in the substrate prior to step (b).

Preferably, the active material is an encapsulated volatile liquid.

Preferably, the second aspect of the invention may incorporate any one or more of the features or preferred features of the first, second or third aspect detailed above.

According to a fifth aspect of the present invention, there is provided a method of producing a delayed release active material product comprising the steps of- - (a) distributing an active material component on and/or in a substrate; (b) adding a barrier composition to the substrate to substantially isolate active material distributed on and/or in the said substrate from the surrounding environment.

Preferably, the fifth aspect of the invention may incorporate any one or more of the features or preferred features of the first, second, third or fourth aspect detailed above.

According to a sixth aspect of the present invention, there is provided a method of producing a delayed release active material composition comprising the steps of-.- (a) distributing an encapsulant containing an active material such as a volatile liquid component on and/or in a support matrix.

Preferably, the support matrix delays or regulates the exposure of the active material encapsulates to the surrounding environment. Preferably, the composition may be used alone or in combination with a substrate in accordance with any preceding aspect of the invention. Preferably, the support matrix is in accordance with one or more the preferred features of the barrier composition herein.

Preferably, the active material is an encapsulated volatile liquid.

Preferably, the second aspect of the invention may incorporate any one or more of the features or the preferred features of the first, second, third, fourth and fifth aspect detailed above.

Preferably, the present invention relates to a porous sheet like substrate in which a water sensitive substance is entrained, which sheet is then coated with a substantially hydrophobic material, such that when the hydrophobic material becomes exhausted in the process of using the article the entrained substance can change its hydration state and thereby become active.

The invention is particularly suitable for fabric conditioning tumble dryer sheets in which the hydrophobic coating is predominantly a hydrophobic cationic surfactant and the isolated material becomes active on the loss of water. The invention is also suitable for a moisturising wipe wherein the hydrophobic coating is an emollient such as skin cream or similar and the isolated material becomes active on the absorption of water. Furthermore a sheet in which such effects are provided by an odiferous encapsulate which gives a fragrance release on exhaustion of the coating, particularly by the incorporation of a water sensitive pro-fragrance, is particularly preferred as this counteracts consumer disappointment at the further inefficacy of the product.

Preferably, the substrate is in sheet form, with entrained isolated material that exhibits activity on the loss or gain of a volatile component. The volatile component may be, but is not necessarily, water. Preferably, the barr ier film or coating is a substantially hydrophobic coating which is delivered to articles,at, preferably, above ambient temperature, to which it is contacted. In this manner, it is substantially removed exposing the isolated material to an atmosphere of differential volatile component concentration thus bringing about activity, preferably, by release of volatile liquid. Preferably, the capsule wall is sensitive to a differential volatile component concentration in the surrounding environment.

A preferred embodiment of the invention is a tumble dryer sheet with entrained encapsulants and a barrier composition comprising hydrophobic fabric softener component. Preferably the encapsulated volatile liquid is a fragrance or volatile silicone, which is also, preferably, isolated by the barrier composition from the surrounding environment until the latter has been removed to the extent that the encapsulate is no longer isolated from the surrounding environment.

The invention is also suitable for use with emollient skin conditioning sheets wherein the sheet contains entrained encapsulants and a coating of substantially hydrophobic emollient material as the barrier composition. The sheet may also optionally contain other active materials. The entrained encapsulate of volatile liquid is preferably, a fragrance or volatile silicone, as hereinbefore described.

Alternatively, the encapsulate may be coated directly with the barrier composition. In a fiwffier alternative, the encapsulate may be suspended in the barrier composition.

It has been surprisingly found that by the use of an encapsulated volatile liquid in conjunction with a barrier composition which is liquid in use that optimum release of the liquid at the end of a process can be achieved. In particular the loss of volatile components early in a process, such as a cleaning process, using a textile sheet or wipe on a surface at above ambient temperature, is avoided whilst delivery when a barrier composition, which itself may have an active role in product performance, has been discharged is facilitated thus giving both a signal to the consumer of the end of such a process and a reduction in the loss of the volatile component.

Advantageously, this invention discloses a product and a method for the delayed release of volatile materials until late in the process thus substantially avoiding their loss and therefore improving their efficacy.

Preferably, the product relates specifically to a porous sheet with entrapped encapsulated volatile materials coated with a hydrophobic substance with a melting point above ambient temperature and below the temperature at which the encapsulates spontaneously rupture. Preferably, the encapsulant contains a volatile plasticiser (e.g. water) and is embrittled on the loss of this 20 plasticiser when the barrier composition such as hydrophobic protective coating is exhausted and the volatile material may be lost.

The invention is particularly suitable for a fabric conditioning tumble dryer sheets in which the barrier composition is an hydrophobic coating which is, preferably, predominantly a hydrophobic cationic surfactant and the encapsulate becomes embrittled after the conditioning process is substantially complete due to the removal of the protective hydrophobic coating, the drying and eninbrittlement of the encapsulant and the subsequently facilitated release of its contents. The invention is also suitable for a moisturising wipe wherein the hydrophobic coating is a skin cream or similar substance and the encapsulate becomes exposed and looses strength on contact with water thus releasing fragrance. Furthermore a sheet in which such effects are combined with a water sensitive colourimetric indicator material is particularly preferred. Particularly suitable fragrances are water sensitive pro-fragrances these being of lower volatility until they come in to contact with water whereby chemical change (tautomerism 1 hydrolysis) releases volatile components. Hence, materials are particularly suitable which change their volatility by a hydrolytic process.

A preferred embodiment of the invention is a tumble dryer sheet with entrained encapsulate of volatile liquid, preferably a fragrance or volatile silicone. The sheet may optionally contain an entrained colourant and hydrophobic softener component which is also coated with the hydrophobic softener component.

Delivery system The present invention also relates to improved solid dryer-activated fabric softener compositions. The compositions may be incorporated into articles of manufacture. The compositions may contain small particle encapsulates in the form of particles (including, where appropriate, agglomerates, pellets, and tablets of said particles). Such compositions contain from about 10 % to about 95% of fabric softening agent and at least an effective amount of said small particle size liquid encapsulate preferably with a water sensitive coating.

Sheet material Substrate In preferred embodiments, the present invention encompasses a substrate comprising articles of manufacture. Representative articles are those that are adapted for use to provide unique perfume benefits and to soften fabrics in an automatic laundry dryer, of the types disclosed in U.S. Pat. Nos. 3,989, 631 Marsan, issued Nov. 2, 1976; 4,055,248, Marsan, issued Oct. 25, 1977; 4,073,996, Bedenk et al., issued Feb. 14, 1978; 4,022,938, Zaki et al., issued May 10, 1977; 4,764,289, Trinh, issued Aug. 16, 1988; 4,808,086, Evans et al., issued Feb. 28, 1989; 4,103,047, Zaki et al., issued Jul. 25, 1978; 3,736,668, Dillarstone, issued Jun. 5, 1973; 3,701,202, Compa et al. , issued Oct. 31, 1972; 3,634,947, Furgal, issued Jan. 18, 1972; 3,633,538, Hoeflin, issued Jan. 11, 1972; and 3,435,537, Rumsey, issued Apr. 1, 1969; and 4,000,340, Murphy et al., issued Dec. 28, 1976, all of said patents being incorporated herein by reference.

Suitable materials which can be used as a substrate in the invention herein include, among others, sponges, paper, and woven and non-woven cloth, all having the necessary absorbency requirements of adsorbing more than its own weight of softener composition. Woven substrates comprise a typical warp and weft, the materials of warp and weft optionally being of differential composition and weight of yarn. This allows one fabric orientation to be the primary adsorbent and the other the primary strength imparting component.

Alternatively such weaves may utilise alternating strands of materials in the warp and/or weft to achieve a similar purpose. A combined cloth of cotton and polyester is particularly suitable. The preferred non-woven cloth substrates can generally be defined as adhesively bonded fibrous or filamentous products having a web or carded fibre structure, or comprising fibrous mats in which the fibres or filaments are distributed haphazardly or in random or pseudo random array with partial orientation of the fibres. Such a non woven mat may be bonded by laying down a hot fibre on itself, as a separate process of spot welding or in continuous welded lines from a heated roller or as regular pattern produced in a similar manner. The latter may also include a textual message or similar. The fibres or filaments can be natural (eg. wool, silk, jute, hemp, cotton, lene, sisal or ramie and mixtures thereof) or synthetic (eg. cellulose ester, polyvinyl derivatives, polyethylene, polypropylene, rayon, polyamides, and polyesters and mixtures thereof).

Preferred polyester non-woven fabric substrates are prepared from a polyester fibre having a denier of from I to 200. The preferred adsorbent properties are obtained by building up the thickness of the cloth, ie. by superimposing a plurality of carded webs or mats to a thickness adequate to obtain the necessary absorbent properties, or by allowing a sufficient thickness of the fibres to deposit on the screen. Any diameter or denier of the fibre (generally up to 10 denier) can be used, inasmuch as it is the free space between each fibre that makes the thickness of the cloth directly related to the absorbent capacity of the cloth, and which, further, makes the non-woven cloth especially suitable for impregnation with a composition by means of capillary or intersectional action. Thus, any thickness necessary to obtain the required absorbent capacity can be used.

Papers suitable for the purpose preferably utilise softwood fibres with a fibre length of preferably greater than Imm more preferably greater than 2mm, most preferably with substantial proportion of length greater than 4mm.

Spruce fibres are particularly preferable. In addition or alternatively polyester fibres may be commingled to obtain suitable paper strength and durability.

Typical articles of manufacture of this type include compositions or articles comprising:

1. a fabric conditioning composition comprising: i. from about 30% to about.

95% of normally solid, dryer softenable material, typically fabric softening agent; and ii. an effective amount, preferably from about 0.25% to about %, of encapsulated volatile liquid having a primary particle size of less than about 25 microns, as described hereinbefore; iii. optionally, an effective amount, preferably from about 0.25% to about 10%, of colourimetric indicator, as described hereinbefore and, optionally,; H. a dispensing means which provides for release of an effective amount of said composition including an effective amount of ii, sufficient to odour release or volatile softener delivery, to fabrics in an automatic laundry dryer at automatic laundry dryer operating temperatures, e. g., from about 3 5. degree. C. to 115 Aegree. C. When the dispensing means is a flexible substrate, e.g., in sheet configuration, the fabric conditioning composition is releasably affixed on the substrate to provide a weight ratio of conditioning composition to dry substrate ranging from about 10: 1 to about 0. 5: 1, preferably from about 5: 1 to about 1: 1.

The invention also comprises the method of use of such an article of manufacture utilising said colourimetric indicators, optionally encapsulated fragrance or softening agent and subsidiary components.

Softener co1pponents The term "fabric softening agent" as used herein includes cationic and nonionic fabric softeners used alone and also in combination with each other, A preferred fabric softening agent of the present invention is a mixture of cationic and nonionic fabric softeners. Examples of fabric softening agents that are especially useful in the substrate articles are the compositions described in U.S. Pat. Nos. 4,103,047, Zaki et al., issued Jul. 25, 1978;, 4,237,155, Kardouche, issued Dec. 2, 1980; 3,686,025, Morton, issued Aug.

22, 1972; 3,849,435, Diery et al., issued Nov. 19, 1974; and U.S. Pat. No.

4,073,996, Bedenk, issued Feb. 14, 1978; said patents are hereby incorporated herein by reference. Another preferred type of fabric softener is described in detail in U.S. Pat. No. 4,661,269, Toan Trinh, Errol H.

Wahl, Donald M. Swartley and Ronald L. Hemingway, issued Apr. 28, 1987, said patent being incorporated herein by reference. Examples of nonionic fabric softeners are the sorbitan esters, C. sub. 12 -C. sub. 26 fatty alcohols, and fatty amines described herein. More biodegradable fabric softener compounds can be desirable. Biodegradability can be increased, e. g., by incorporating easily destroyed linkages into hydrophobic groups. Such linkages include ester linkages, amide linkages, and linkages containing unsaturation and/or hydroxy groups. Examples of such fabric softeners can be found in U.S. Pat. Nos. 3,408,361, Mannheimer; 4,709,045, Kubo et al; 4,233,451, Pracht et al.; 4,127,489, Pracht et al.; 3,689,424, Berg et al. ; 4,128,485, Baumann et al.; 4,161,604, Oster et al.; 4,189,593, Wechsler et al.; and 4,339,391, Hoffinan et al., said patents being incorporated herein by reference. A preferred article of the present invention includes a fabric treatment composition which comprises from about 0.5% to about 30%, preferably from about 1 % to about 10 %, more preferably from about 1. 5 % to about 5%, of encapsulated volatile liquid, as discussed hereinbefore, and from about 30% to about 95%, preferably from about 40% to about 90%, of fabric conditioning (softening) agent. Preferably, said fabric softening agent is selected from cationic and nonionic fabric softeners and mixtures thereof. Preferably, said fabric softening agent comprises a mixture of about % to about 95 % of a cationic fabric softener and/or about 5 % to about 95 % of a nonionic fabric softener by weight of said fabric treatment agent. The selection of the components is such that the resulting fabric treatment composition has a melting point above about 37 Aegree. C. and is flowable 5 at dryer operating temperatures.

Fragrance co!jiponents, The perfume ingredients and compositions of this invention are the conventional ones known in the art. Selection of any perfume component, or amount of perfume, is based on aesthetic considerations. Suitable perfume compounds and compositions can be found in the art including U.S. Pat. Nos. 4,145,184, Brain and Cummins, issued Mar. 20, 1979; 4,209,417, Whyte, issued Jun. 24, 1980; 4,515,705, Moeddel, issued May 7, 1985; and 4,152,272, Young, issued May 1, 1979, all of said patents being incorporated herein by reference. Many of the art recognized perfume compositions are relatively substantive, as described hereinafter, to maximise their odour effect on substrates. However, the use of cyclodextrin/perfume complexes may de 20 used to improve substantivity andlongevity of perfume. A substantive perfume is one that contains a sufficient percentage of substantive perfume materials so that when the perfume is used at normal levels in products, it deposits a desired odour on the treated fabric. In general, the degree of substantivity of a perfume is roughly proportional to the percentage of 25 substantive perfume material used. Relatively substantive perfumes contain at least about 1%, preferably at least about 10%, substantive perfume materials. Substantive perfume materials are those odorous compounds that deposit on substrates via the treatment process and are detectable by people with normal olfactory acuity. Such materials typically have vapour pressures 30 lower than that of the average perfume material. Also, they typically have molecular weights of about 200 or above, and are detectable at levels below those of the average perfume material. Perfumes can also be classified according to their volatility, as mentioned hereinbefore. The highly volatile, low boiling, perfume ingredients typically have boiling points of about 250 35 Aegree. C. or lower. Many of the more moderately volatile perfume ingredients are also quickly lost. For example, substantially all of such perfumes are lost in the drying cycle of a typical laundry process. The moderately volatile perfume-ingredients are those having boiling points of from about 250 degree. C. to about 300 degree. C. The less volatile, high 40 boiling, perfume ingredients referred to hereinbefore are those having boiling points of about 300. degree. C. or higher. A significant portion of even these high boiling perfume ingredients, considered to be highly substantive, can be lost, during a laundry drying cycle, and it is desirable to have means to retain more of these ingredients on the fabrics. Many of the perfume ingredients as discussed hereinafter, along with their odour characters, and their physical and chemical properties, such as boiling point and molecular weight, are 5 given in Terfume and Flavour Chemicals (Aroma Chemicals), " Steffen Arctander, published by the author, 1969, incorporated herein by reference. Examples of the highly volatile, low boiling, perfume ingredients are: anethole, benzaldehyde, benzyl acetate, benzyl alcohol, benzyl formate, iso-bornyl acetate, camphene, cis-citral (neral), citronellal, citronellol, 10 citronellyl acetate, para-cymene, decanal, dihydrolinalool, dihydromyrcenol, dimethyl phenyl carbinol, eucaIyptol, geranial, geraniol, geranyl acetate, geranyl nitrile, cis-3-hexenyl acetate, hydroxycitronellal, d-limonene, linalool, linalool oxide, linalyl acetate, linalyl propionate, methyl anthranilate, alpha-methyl ionone, methyl nonyl acetaldehyde, methyl phenyl 15 carbinyl acetate, laevo-menthyl acetate, menthone, iso-menthone, myrcene, myrcenyl acetate, myrcenol, nerol, neryl acetate, nonyl acetate, phenyl ethyl alcohol, alpha-pinene, beta-pinene, gamma-terpinene, alpha- terpineol, beta-terpineol, terpinyl acetate, and vertenex (para-tertiary- butyl cyclohexyl acetate). Some natural oils also contain large percentages of highly volatile 20 perfume ingredients. For example, Iavandin contains as major components:

linalool; linalyl acetate; geraniol; and citronellol. Lemon oil and orange terpenes both contain about 95 % of d-limonene. Examples of moderately volatile perfume ingredients are: amyl cinnamic aldehyde, iso- arnyl salicylate, beta-caryophyllene, cedrene, cinnamic alcohol, coumarin, dimethyl benzyl 25 carbinyl acetate, ethyl vanillin, eugenol, isoeugenol, flor acetate, heliotropine, 3-cis-hexenyl salicylate, hexyl salicylate, lilial (para- tertiarybutyl-alpha-methyl hydrocinnamic aldehyde), gamma-methyl ionone, nerolidol, patchouli alcohol, phenyl hexanol, beta-selinene, trichloromethyl phenyl carbinyl acetate, triethyl citrate, vanillin, and 30 veratraldehyde. Cedarwood terpenes are composed mainly of alpha- cedrene, beta-cedrene, and other C. sub. 15 H. sub. 24 sesquiterpenes. Examples of the less volatile, high boiling, perfume ingredients are: benzophenone, benzyl s a 1 i c y 1 a t e, ethylene brassylate, g a 1 a x o 1 i d e (1,3, 4,6,7,8-hexahydro-4,6,6,7,8,8-hexamethyl-cyclo-penta-gama-2-benzopy 35 ra n), hexyl cinnamic aldehyde, lyral (4-(4-hydroxy-4-methyl pentyl)-3 -cyclohexene- 1 0-carboxaldehyde), methyl cedrylone, methyl dihydro jasmonate, methyl-beta-naphthyl ketone, musk indanone, musk ketone, musk tibetene, and phenylethyl phenyl acetate.

EncUsulation As used herein the term encapsulate refers to a particulate material in which comprises a liquid or substantially liquid phase or phases surrounded completely by a barrier or membrane which is substantially impermeable to the said liquid phase material(s).

The encapsulated liquid may be any volatile liquid such as those with a detergent function examples being:

Cyclic Silicones, Volatile silicones, Polydimethyl siloxanes Liquid surfactants (eg Synperonic A3, A3 {ICI}) Bleach precursor (eg Glycerol triacetate) Antifoarn (e.g. poly dimethyl siloxane) Perfumes Perfume precursors (e.g. esters, enols of volatile aldehydes and ketones) also mixtures of the above or in combination with solid components such that the viscosity of the encapsulate remains essentially liquid, i.e. with a viscosity of less than 10 Pascal seconds at 20s-1 shear rate (as for example measured by a Haake viscometer with a cylindrical measuring cup and bob).

The encapsulating material may be any material which gives a particulate encapsulate where no part of the encapsulated liquid can directly contact its surrounding. It is recognised that in commercial production some encapsulate material will inevitably remain un-encapsulated and some coating remain unused. This invention does not therefore rely on the success of the encapsulation procedure or of the amount or proportion of any liquid or liquids present that have been encapsulated but on the presence of encapsulated material per se.

Suitable encapsulating materials are illustrated by the following nonlimiting examples:

Organic polymers - Addition polymers - e.g. Poly Vinyl; ethers, 35 esters, amides, carboxylates, maleates, methacrylates, acrylates, alcohols, acetates and copolymers thereof. - Corlensation polymers - eg Poly; esters, and urethanes, gelatin, xanthan gums, guar gum, 40 alginates.

The encapsulates will typically consist of largely spherical structures filled at least in part with the desired liquid, the remainder being either liquid vapour, air, nitrogen, argon or similar. These structures may consist of aggregates of multiples of these primary structures as may typically be produced during the 5 encapsulation process.

The encapsulates may typically be produced by emulsifying the desired liquid in another liquid, the introduction of an amphiphillic polymer or monomer which will reside largely at the interface of the droplets. This emulsion or suspension is then reacted to polymerise and / or cross link to form suspended encapsulate which is then used as such or removed by filtration, centrifugation or other suitable means.

The invention is also suitable for use in an emollient hand cleansing sheet or similar in which case a softening component will typically consist of a hydrophobic emollient oil.

Colourimetric indicator coAppound The preferred colourimetric indicators are Copper Sulphate or Cobalt Chloride. These materials will typically be entrained in the fabric relying on simple physical entrapment or with the aid of a polymeric adjuvant. Particle sizes of between 100 and 1Ogm are preferred. In particular the colourimetric indicator may be applied in a hydrated for and subsequently dried in situ on the sheet. In this case the indicator may be added as a solution. Alternatively the fine indicator particles will be mixed to a paste like composition with polyvinyl alcohol and an inert filler such as sodium sulphate or sodium chloride. Such a paste can be injected on to the sheet either as localised patches or in a pattern form such as to give a textual message.

Other colourimetric indicators are disclosed in SU 1,269,007 and include dyes which change their shade depending upon the concentration of water present. Such dyes as change their colour by 2 delta E units or more, preferably by 5 units or more on the CIElab colour scale as known in the art and described R McDonald, -Society of Dyers and in 'Colour Physics for Industry.

Colourists, 1987 are considered suitable. Such a colour change should occur on a change in their water content from 0. 5 % to 500 % water by weight (ie dry to very concentrated solution). Suitable materials are as described in the Colour Index, Society of Dyers and Colourists (UK) and include example materials of Colour index numbers 10020, 13015, 10316, 13065, 14720, 14600, 14700, 14720, 14815, 15510, 15620, 15850, 15980, 15985, 16035, 16150, 16155, 16135, 16230, 16255, 16290, 17200, 18050, 18130, 18690, 18736, 18820, 18950, 18956, 19140, 20470, 24790, 27290, 27755, 28440, 40215, 42051, 42052, 42053. It is noted that the person skilled in the art would choose the crystalline form of such materials so as to best facilitate the observation of the shade change consistent with the hydration and drying of these materials.

Emollient oils Suitable emollient oils can be chosen from the wide range known in the art, for example Lanolin. Esters with a combined alkyl chain length of between 20 and 40 are particularly preferred. Examples include PELEMOL CA, Cetyl Acetate, PELEMOL CL, Cetyl Lactate, PELEMOL SPO, Cetearyl Octanoate, PELEMOL 168, Cetyl Octanoate, PELEMOL CP, Cetyl Palmitate, PELEMOL CR, Cetyl Ricinoleate, PELEMOL 1215L, C12-15 Alkyl Lactate, PELEMOL 30013, C20-40 Alkyl Behenate, PELEMOL DO, Decyl Oleate, PELEMOL DES, Diethyl Sebacate, PELEMOL HAB, Dihydroabietyl Behenate, PELEMOL DIA, Diisopropyl Adipate, PELEMOL DIPS, Diisopropyl Sebacate, PELEMOL DNPA, Dipropyl Adipate, PELEMOL DOA, Dioctyl Adipate, PELEMOL DOM, Dioctyl Maleate, PELEMOL DICA, Diisocetyl Adipate, PELEMOL G7A, Glycereth-7 Triacetate, all materials ex Pheonix chemicals, Pelemol is a Trademark.

Such materials may be used alone or in combination and may include subsidiary components such as coulourants, dissolved fragrance, bactericides, other preservatives, solvents anti-ageing ceramides and other materials known in the art for such purposes.

Substrate In a preferred substrate article embodiment, the fabric trealtment compositions are provided as an article of manufacture in combination with a dispensing means such as a flexible substrate which effectively releases the composition in an automatic laundry (clothes) dryer or by sustained manual use. Such dispensing means can be designed for single usage or for multiple uses. The dispensing means can also be a "carrier material" that releases the fabric softener composition and then is dispersed and/or exhausted from the dryer. The dispensing means will normally carry an effective amount of fabric treatment composition. Such effective amount typically provides sufficient fabric conditioning agent and/or anionic polymeric soil release agent for at least one treatment of a minimum load in an automatic laundry dryer. Amounts of fabric treatment composition for multiple uses, e.g., up to about 30, can be used. Typical amounts for a single article can vary from about 0.25 g to about 100 g, preferably from about 0.5 g to about 20 g, most preferably from about 1 g to about 10 g. One such article comprises a sponge material releasably enclosing enough fabric treatment composition to effectively impart fabric soil release and softness benefits during several cycles of clothes. This multi-use article can be made by filling a hollow sponge with about 20 grams of the fabric treatment composition. Other devices and articles suitable for dispensing the fabric treatment composition into automatic dryers include those described in U.S. Pat. Nos. 4,103,047, Zaki et al., issued Jul. 25, 1978; 3,736,668, Dillarstone, issued Jun. 5, 1973; 3,701,202, Compa et al., issued Oct. 31, 1972; 3,634,947, Furgal, issued Jan. 18, 1972; 3,633,538, Hoeflin, issued Jan. 11, 1972; and 3,435,537, Rumsey, issued Apr. 1, 1969. All of these patents are incorporated herein by reference. Highly preferred paper, woven or non-woven "absorbent" substrates useful herein are fully disclosed in U. S. Pat. No. 3,686,025, Morton, issued Aug. 22, 1972, incorporated herein by reference. It is known that most substances are able to absorb a liquid substance to some degree; however, the term "absorbent" as used herein, is intended to mean a substance with an absorbent capacity (i.e., a parameter representing a substrate's ability to take up and retain a liquid) from 4 to 12, preferably 5 to 7, times its weight of water.

Method of product application The substrate embodiment of this invention can be used for imparting the above-described fabric treatment composition to fabric to provide odour control and/or perfume effects and/or softening and/or antistatic effects to fabric in an automatic laundry dryer comprises: commingling pieces of damp fabric by tumbling said fabric under heat in an automatic clothes dryer with an effective amount of the fabric treatment composition, at least the continuous phase of said composition having a melting point greater than about 37.degree. C.

Subsidiary components Well known optional components included in fabric conditioning compositions are narrated in U.S. Pat. No. 4,103,041, Zaki et al., issued Jul. 25, 1978, for "Fabric Treatment Compositions," incorporated herein by reference. Another preferred additional ingredient in the compositions herein is free perfume, other than the perfume which is present as or in any complex or as a pro-perfume. A pro-perfume being one which releases an active oderific substituent or component on chemical reaction induced by a condition peculiar to an in-use condition, which is also very useful for imparting the - is - odour benefits. Uncomplexed perfume is preferably present at a level of from about 0. 10 % to about 10 % by weight of the total. For example, perfume delivery both via free perfume and encapsulates, in solid, dryer- activated, fabric conditioning compositions in laundry fabric dryers is desirable in two ways. Product malodours can be covered by the addition of free perfume to the softener composition to obtain a more preferred product odour, and complexed perfume can be transferred onto fabric with the softener actives in the laundry fabric dryer to provide better in-wear fabric odour. (Preferably, such uncomplexed perfume comprises at least about 1 %, more preferably at least about 10% by weight of said uncomplexed perfume, of substantive perfume materials.) The following are non limiting examples Two encapsulates were prepared Encapsulate a - Hydro-sensitve coating Testor' Perfume composition 78 % Gelatine encapsulant 21 %, glycerol gelatine plasticiser 1 % Encapsulate b - Hydro insensitive coating Testor' Perfume composition 85 % Acrylonitrile encapsulant 15 % The encapsulates were prepared by methods known in the art by Callesence UK Ltd.

Each encapsulant was dusted on to the sheet material to a weight of about 7 % and then sprayed with 0. 1 g square centimetre of polyvinyl alcohol MW 50,000 in ethanol (30% wlw) binder and left to air dry.

Testor' perfume composition Component wt.

Alpha Pinene 5.0 Benzyl Acetate 5.0 Cournarin 5.0 Eugenol 5.0 Benzyl Salicylate 10.0 Dihydro Myrcenol 10.0 Lavandin 20.0 Lemon Oil CP 20.0 Hexyl Cinnamate 20.0 Total 100.0 5 All chemicals were ex Aldrich Chemical Co.

Coating of tumble d1yer sheets Ditallowalkyldi-methylammonium sulphate (ex Sherex Chemical Co.) is melted at about 90.degree. C. and then sprayed on to the pre-prepared sheet material at a distance of about 15cm at such a rate as to avoid heating the sheets about 25'C. The material was added to form a total of between 60 and 65% weight/weight of final sheet. An average thickness of the layer was determined to be 150/4m by microscopy. The appropriate stages were omitted to prepare the various variants tabulated. Post addition of the encapsulate was achieved by coating the sheet with softener and then dusting the sheet with the encapsulate.

Coating of cosmetic emollient wip Lanolin ex Aldrich is melted at about 120 Aegree. C. and then sprayed on to the pre-prepared sheet material at a distance of about l5cm. at such a rate as to avoid heating the sheets above 25C. The material was added to form a total of between 50 and 55% weight/weight of final sheet. The average thickness of the protective coating was 150,um determined by microscopy. The appropriate stages were omitted to prepare the various variants tabulated.

Textile washing and conditioning 30 A dryer (White knight model Sensodry on 'high setting) was loaded with 4kg of wet terry towelling pre-washed (Hotpoint 1200 washing machine with spin speed of 1200rpm). The wash was performed using soft water (6'Fh) and 30g of sodium silicate and 5g of Synperonic A7 (ex ICI) surfactant in 90'C main wash cycle.

A single tumble dryer sheet weighing 25g was added to the dryer and the load dried until the weight of the cloth was reduced in weight to less than 2.3kg (i.e. dry to the touch).

The odour of two separate pieces of towelling was then scored on a scale of 40 0 to 5. 0 no odour, 5 is very strong odour, by five assessors. The scores were then averaged and rounded to the first decimal.

Tumble dryer sheet Perfume evaluation Substrate Conditioner Encapsulate Encapsulate Post addition only A only A and fabric of conditioner Encapsulate A Paper 0 0.5 3.0 0.7 Non-woven 0 0.8 3.5 0.7 polyester Knitted 0 0.9 3.2 0.8 cotton table continuation Substrate Encapsulate B and fabric conditioner Paper 2.4 Non-woven 2.7 polyester Knitted 2.4 cotton Cosmetic emollient Eipe 20 Each sheet type was used by ten panellists who had previously washed their hands in a 10% solution of Synperonic A7 (ex ICI) surfactant, thoroughly rinsed. One use of the sheet constituted placing the sheet between the palm of one hand resting on the back of the other and rotating the hands to swap the upper and lower hands in a stereotypical hand wringing motion for a total of ten passes. The odour of the hands was then score on a scale of 0 to 5. 0 no odour, 5 is very strong odour by three assessors. The scores were then averaged and rounded to the first decimal.

The sheets were stored at ambient conditions in a ventilated room for 12 hours between uses.

Sheet odour Initial after use 1 after use 2 after use 3 Sheet only 0 0 0 0 Sheet with 1.4 5 0.3 0.1 encapsulate A Sheet with 0.5 3 2.3 0.1 emollient and encapsulate A Sheet with 0.5 3 2.1 1.7 emollient and encapsulate B Emollient loss was determined by soxhlet extraction of the sheet with acetone, drying the residue taking this as the residual emollient after deducting the weight of encapsulate used and hence extracted.

Emollient efficacy, % loss of emollient from sheet Initial after use 1 after use 2 after use 3 Sheet only 0 0 0 0 Sheet with 0 0 0 0 encapsulate A Sheet with 0% 78% 88% 93% emollient and encapsulate A Sheet with 0% 75% 89% 91% emollient and encapsulate B This demonstrates the continued presence of fragrance from encapsulate B after the sheet has lost its emollient efficacy whereas water sensitive encapsulate A rapidly looses fragrance activity after the emollient efficacy has been substantially lost.

The following are non limiting examples Three colourants were prepared Colourant A - Copper Sulphate, Average particle size 10Ogin Colourant B Cobalt Chloride, Average particle size 125gm Colourant C - Iragon Blue ABL 80 ex Ciba Each colourant was dusted on to the sheet material to a weight of about 7 % and then sprayed with 0. l g square centimetre of polyvinyl alcohol MW 50,000 in ethanol (30% w/w) binder and left to air dry.

All chemicals were ex Aldrich Chemical Co. unless stated otherwise Coating of tumble dryer sheets Ditallowalkyldi-methylammonium sulphate (ex Sherex Chemical Co.) is melted at about 90.degree. C. and then sprayed on to the pre-prepared sheet material at a distance of about 15cm at such a rate as to avoid heating the sheets above 25'C. The material was added to a total weight of pre-prepared sheet between 60 and 65%. The appropriate stages were omitted to prepare the various variants tabulated.

Coating of cosmetic emollient wipe The sheet with colourant was first dryed at 90C to constant weight. Lanolin ex Aldrich is melted at about 120 degree. C. and then sprayed on to the pre- prepared sheet material at a distance of about 15cm at such a rate as to avoid heating the sheets above 5WC. The material was added to a total weight of preprepared sheet between 50 and 55 %. The appropriate stages were omitted to prepare the various variants tabulated.

Textile washing and conditioning A dryer (White knight model Sensodry on 'high setting3 was loaded with 4kg of wet terry towelling pre-washed (Hotpoint 1200 washing machine with spin speed of 120Orpm). The wash was performed using soft water (6"Fh) and 30g of sodium silicate and 5g of Synperonic A7 (ex ICI) surfactant in 9WC main wash cycle.

The odour of two separate pieces of towelling was then scored on a scale of 0 to 5. 0 no odour, 5 is very strong odour, by five assessors. The scores were then averaged and rounded to the first decimal.

Colour measurement The colour of the sheets was measured using a McBeth Colour Eye 3100_ colourimeter using the CIElab L, a, b (CIE 1976) colour space measurements. The difference in the colour in terms of delta E ab (i.e. the square root of the sum of the squares of the differences in the L, a and b measures before and after the use of the product). was then determined for an area of the sheet. Results were rounded to the first decimal. Each reading was 5 an average of five separate readings.

Tumble dryer sheet Colour change, delta E, readings evaluation AE After 5 minutes drying at which time the load was still predominantly wet, Substrate Conditioner Colourant A Colourant A Colourant A only only and fabric and fabric conditioner conditioner on separate halves of the sheet Paper 0 > 10 0.1 >10 Non-woven 0 >10 0.1 > 10 polyester Knitted 0 >10 0.2 >10 cotton Read from most intensely coloured part of the sheet.

AE After drying.

Substrate Conditioner Colourant A Colourant A Colourant A only only and fabric and fabric conditioner conditioner on separate halves of the sheet Paper 0 >10 >10 >10 Non-woven 0 > 10 >10 >10 polyester Knitted 0 >10 >10 >10 cotton Read from most intensely coloured part of the sheet.

Cosmetic emollient wip Each sheet type was used by ten panellists who had previously washed their hands in a 10% solution of Synperonic A7 (ex ICI) surfactant, thoroughly rinsed. One use of the sheet constituted placing the sheet between the palm of one hand resting on the back of the other and rotating the hands to swap the upper and lower hands in a stereotypical hand wringing motion for a specified number of passes. The colour of the sheet was measured before and after.

AE After five hand movements.

Substrate Emollient Colourant A Colourant A Colourant A only only and emollient and emollient on separate halves of the sheet Paper 0 > 10 4.0 >10 Non-woven 0 >10 3.1 >10 polyester Knitted 0 > 10 4.3 >10 cotton Read from most intensely coloured part of the sheet.

AE After ten hand movements.

Substrate Emollient Colourant A Colourant A Colourant A only only and and emollient Emollient on separate halves of the sheet Paper 0 >10 >10 > 10 Non-woven 0 >10 >10 > 10 polyester Knitted 0 >10 >10 >10 cotton Read from most intensely coloured part of the sheet.

Emollient loss was determined by soxhiet extraction of the sheet with acetone, drying the residue taking this as the residual emollient after deducting the weight of encapsulate used and hence extracted.

Emollient efficacy, % loss of emollient from sheet Initial after 5 after 10 hand after 20 hand hand movements movements movements Sheet only 0 0 0 0 Sheet with 0 0 0 0 colourant A Sheet with 0% 58% 75% 81% emollient and colourant A This demonstrates the apposite nature of the colour change in relation to the potential residual emollient efficacy of the sheet.

AE After five hand movements.

Substrate Emollient Colourant B Colourant B Colourant B only only and and Emollient Emollient hand 10 hand movements movements Paper 0 >10 1.8 9.3 Non-woven 0 >10 2.0 >10 polyester Knitted 0 >10 1.4 8.1 cotton Read from most intensely coloured part of the sheet.

AE After ten hand movements.

Substrate Emollient Colourant C Colourant C Colourant C only only and and Emollient Emollient hand 10 hand movements movements Paper 0 >2 0.7 >2 Non-woven 0 > 2 0.3 > 2 polyester Knitted 0 > 2 0.4 > 2 cotton The reader's attention is directed to all papers and documents which are filed concurrently with or previous to this specification in connection with this application and which are open to public inspection with this specification, and the contents of all such papers and documents are incorporated herein by reference.

All of the features disclosed in this specification (including any accompanying claims, abstract and drawings), and/or all of the steps of any method or process so disclosed, may be combined in any combination, except combinations where at least some of such features and/or steps are mutually exclusive.

Each feature disclosed in this specification (including any accompanying claims, abstract and drawings), may be replaced by alternative features serving the same, equivalent or similar purpose, unless expressly stated otherwise. Thus, unless expressly stated otherwise, each feature disclosed is one example only of a generic series of equivalent or similar features.

The invention is not restricted to the details of the foregoing embodiment(s). The invention extends to any novel one, or any novel combination, of the features disclosed in this specification (including any accompanying claims, abstract and drawings), or to any novel one, or any novel combination, of the steps of any method or process so disclosed.

Claims

1. A product having delayed release active material, comprising a substrate and encapsulates of a volatile liquid distributed on and/or in the substrate, wherein a barrier composition is present on the substrate to substantially isolate encapsulates distributed on and/or in the said substrate from the surrounding environment.

2. A fabric conditioning composition comprising a fabric conditioning matrix operable as a barrier composition and encapsulates of active material dispersed in the said matrix.

3. A product having a delayed release active material comprising a substrate and an active material distributed on and/or in the substrate, wherein a barrier composition is present on the substrate to substantially isolate the said active material from the surrounding environment.

4. A product according to claim 3, wherein the active material is a volatile liquid encapsulated by an encapsulating material.

5. A product according to any of claims 2 to 4, wherein the active material is known to have a beneficial effect in laundry drying applications.

6. A product according to any of claims 2 to 5, wherein the active material is selected from perfumes, colour indicators, cyclic silicones, volatile silicones, polydimethyl silicones, liquid surfactants, bleach precursors, antifoaming agents and/or perfume precursors.

7. A method of producing a delayed release active material product comprising the steps of:- (a) distributing an active material component on and/or in a substrate; (b) adding a barrier composition to the substrate to substantially isolate active material distributed on and/or in the said substrate from the surrounding environment.

8. A method according to claim 7, wherein a colour indicator is distributed on and/or in the substrate prior to step (b).

9. A method of producing a delay release active material composition comprising the step of:

(a) distributing an encapsulant containing an active material component on and/or in a support matrix of fabric conditioner.

10. A method according to claim 9, wherein a colour indicator is distributed on and/or in the substrate prior to step (b).

11. A product or method according to any of claims 1 or 3 to 8, wherein there is a colour indicator component distributed on and/or in the substrate, wherein a barrier composition is present on the substrate to also substantially isolate colour indicator distributed on and/or in the said substrate from the surrounding environment.

12. A method according to any of claims 7 to 11, wherein the active material is a volatile liquid encapsulated by an encapsulating material.

13. A product or method according to any preceding claim, wherein the barrier composition forms a film or coating on the substrate, at least in use.

14. A product or method according to claim 13, wherein the film or coating is substantially continuous across at least one substrate area where active material is present.

15. A product or method according to claim 13 or 14, wherein the barrier composition forms a film or coating across all the surface area of the substrate so that substantially all the active material is isolated by the barrier composition.

16. A product or method according to any of claims 1 to 8 or 11 to 15, wherein the baff ier composition is, in use, removed from the substrate by contact with other substances or articles.

17. A product or method according to claim 16, wherein the barrier composition is, in use, progressively removed by contact with other.

substances or articles.

18. A product or method according to claim 16 or 17, wherein the barrier composition is a fabric softener.

19. A product or method according to claim 1, wherein the volatile liquid is a volatile fragrance.

20. A product or method according to any of claims I or 3, wherein the substrate is a tumble dryer sheet of the type used as disposable tumble dryer sheets.

21. A product according to claim 20, wherein the composition is operable to be progressively removed during the drying action to gradually expose the active material to the surrounding environment in the dryer.

22. A product or method according to any of claims I to 8 or 11 to 2 1, wherein the barrier composition is hydrophobic.

23. A product or method according to any of claims 3 to 8 or 11 to 22, wherein the active material is sensitive to a differential concentration of volatile component in the surrounding environment.

24. A product or method according to claim 23, wherein the active material component is sensitive to water.

25. A product or method according to any of claims 23 or 24, wherein the barrier composition is hydrophobic and the active material is sensitive_ to water gain. 25

26. A product or method according to any of claims 23 to 25, wherein the barrier composition is hydrophobic and the active material is sensitive to water loss. 30

27. A product or method according to claim 23, wherein the barrier composition is, in use, progressively removed by contact with a dryer load until the active material is directly exposed to the atmosphere in the dryer, resulting in loss of water or other volatile component from the active material and a resultant activation of active material. 35

28. A product or method according to any of claims I or 3 to 8, wherein the substrate is a moisturising wipe.

29. A product or method according to claim 28, wherein the barrier 40 composition is an emollient cream or the like.

30. A product or method as hereinbefore described with reference to any one or more of the examples.

31. A method of softening clothes comprising the step of: 5 locating a product according to any of claims 1-3, having a barrier composition which comprises a fabric softener, in contact with a dryer load in a dryer for a period of time suitable to remove at least some of the fabric softener and to thereby at least partially expose the encapsulates or active material to the environment in the dryer.

32. A method according to claim 31, which includes the step of exposing the encapsulates to the environment in the dryer for a period of time suitable to cause the protective layer of the encapsulate to at least is partially release the encapsulate contents.