EP2310480B1

EP2310480B1 - Improvements relating to fabric conditioners

Info

Publication number: EP2310480B1
Application number: EP09802479A
Authority: EP
Inventors: Jane Howard; Robert Allan Hunter; Jeremy Robert Westwell; Janice Elaine Wright
Original assignee: Unilever PLC; Unilever NV
Current assignee: Unilever PLC; Unilever NV
Priority date: 2008-07-29
Filing date: 2009-07-15
Publication date: 2013-01-02
Anticipated expiration: 2029-07-15
Also published as: ZA201100170B; WO2010012590A1; BRPI0916561A2; EP2310480A1; BRPI0916561B1; ES2402487T3; PL2310480T3; AR072841A1; CN102112591B; CN102112591A

Description

Technical Field

The present invention relates to stable liquid fabric softener compositions containing encapsulates.

Background and Prior Art

The use of encapsulated perfumes and perfume components (encamps) in fabric conditioners is now well known and is advantageous because it enables improved storage and delivery of perfumes and perfume components. Such technologies provide enhanced fragrance delivery over conventional free perfume oil by overcoming the issue of perfume loss during the drying process because the perfume is protected in the capsule.
WO2006/131846 discloses substantially non-aqueous cleaning or conditioning compositions comprising a fragrance encapsulated in aminoplast type microcapsules, and addresses the problem of instability of the perfume capsules themselves.
EP1589092 discloses fabric conditioner compositions comprising encapsulated fragrances, and describes the stabilising effect of non-ionic surfactants on the encapsulate slurry itself.
WO2008/016637 discloses fabric conditioner compositions comprising ester-linked quaternary ammonium compounds and particles having a polymeric wall material surrounding a benefit agent, which is a fragrance.
US2006/252669 discloses a fabric softener composition comprising cationic or non-ionic softening compound, a cross-linked cationic polymer and at least one fabric or skin beneficiating ingredient contained within a microcapsule.
Some known perfume encaps have weak acid groups present on the surface of the capsule wall or shell, for example, those disclosed in US2007/0138672 , EP-A-1407754 , EP-A-1533364 , EP-A-1797946 , EP-A-1797947 , EP-A-1407753 , EP-A-1589092 (all International Flavours and Fragrances Inc) and W02008/005693 (Colgate-Palmolive Company). These mainly arise from the use of a carboxylate based polymeric cross-linker during production of the polymeric shell.
However, we have found that, when incorporated into a fabric conditioner composition, such encaps lead to relatively poor visco-stability and a shorter shelf life of the composition. Even where a stable slurry of encaps is available, viscostability of the overall fabric conditioner composition is reduced. Compositions which contain encaps having all or a majority of strong acid groups on the wall surface instead of weak acid groups or which do not have any of the aforementioned weak or strong acid groups present on the surface are comparatively more stable.
Without being bound by theory, we believe that the fact that weak acids do not fully dissociate into the ionic form but are in dynamic equilibrium between the molecular (major) and ionic (minor) forms has a negative effect on the stability of the fabric conditioner compositions. Once the weak acid is in the ionic form it can complex with metal ions, protons or active molecules (such as quaternary ammonium softening active). This complexation results in a dynamic equilibrium forming between the minor ionic form and the major molecular form. This dynamic, ever shifting equilibrium between the two forms leads to an unstable system. This is particularly marked in the case where the weak acid groups complex with a quaternary ammonium compound as this forms a solid, the uncomplexed phase being a liquid. The problem is exacerbated by the fact that the weak acid equilibrium changes with pH and the pH of fabric conditioner compositions is known to change upon storage.
We have now found that this problem can be reduced or eliminated by the addition of a suitable mobile material, such as a water soluble quaternary ammonium compound or a nonionic surfactant into the formulation. Without wishing to be bound by theory, we believe that the weak acid complexes preferentially with the added mobile species, instead of the softening active, thus resulting in a more stable system.
This invention allows perfume encapsulates having surface weak acid groups to be incorporated into a fabric conditioner without loss of stability, thus enabling the use of a wider range of perfumes as well as extending the shelf life of the product.

Statement of the Invention

In a first aspect of the invention, there is provided a liquid softening composition comprising:

i) encapsulated perfume components,
ii) a fabric softening active, which is an ester-linked quaternary ammonium compound;
iii) a stabilising active selected from the group consisting of from 0.05 to 0.2 wt% by the total weight of the composition of water soluble non-ester-linked cationic quaternary ammonium compound(s), from 0.65 to 1.5 wt% by the total weight of the composition of non-ionic surfactant(s) and mixtures thereof, and
iv) from 0.005 to 0.1 wt% by the total weight of the composition of salt,

A second aspect of the invention provides a method of stabilising a liquid fabric conditioning composition comprising encapsulated perfume components, a fabric softening active, which is an ester-linked quaternary ammonium compound and from 0.005 to 0.1 wit% by the total weight of the composition of salt, wherein the encapsulates comprise a capsule wall having surface weak acid groups, comprising the step of adding a stabilising active selected from the group consisting of from 0.05 to 0.2 wt% by total weight of the composition of water soluble non-ester-linked cationic quaternary ammonium compounds, from 0.65 to 1.5 wt% by total weight of the composition of non-ionic surfactants and mixtures thereof to the composition, wherein the surface weak acid groups comprise carboxylate containing groups, represented by the formula (-C(OH)=O).

Detailed Description of the Invention

The Encaps

The encaps (also referred to herein as "capsules") for use in the present invention comprise a shell and a perfume core. The shell is comprised of materials having weak acid groups on the surface, such as surface carboxylic acid groups or moieties. In the context of this invention by "surface carboxylate containing groups or moieties" is meant that the encapsulate shell wall has a plurality of carboxylate containing groups on its outer surface, which can interact with species in the composition. By "weak acid groups" is meant those proton donating groups that are found on weak acids, i.e. acids that only partially dissociate in aqueous solution, for example, the so-called "organic acids".
Fragrance capsules known in the art and suitable for use in the present invention comprise a wall or shell comprising a three-dimensional cross-linked network of an aminoplast resin, more specifically a substituted or un-substituted acrylic acid polymer or co-polymer cross-linked with a ureaformaldehyde pre-condensate or a melamine-formaldehyde pre-condensate; and having surface weak acid groups.
Microcapsule formation, suitable for use in the present invention, using (i) melamine-formaldehyde or ureaformaldehyde pre-condensates and (ii) polymers containing substituted vinyl monomeric units having carboxy-proton-donating functional group moieties (e.g. carboxylic acid anhydride groups) bonded thereto is disclosed in UK published Patent Application GB 2,006,709 A .
The weak acid groups include any carboxylate containing group, represented by the following formula:-(-C(OH)=O)
These typically arise during the preparation of the encapsulate shell wall, when the shell wall is formed of one or a blend of the following cross-linking carboxylated polymers:-

(i) an acrylic acid polymer;
(ii) a methacrylic acid polymer;
(iii) an acrylic acid-methacrylic acid co-polymer;
(iv) an acrylamide-acrylic acid co-polymer;
(v) a methacrylamide-acrylic acid co-polymer;
(vi) an acrylamide-methacrylic acid co-polymer;
(vii) a methacrylamide-methacrylic acid co-polymer;
(viii) a C₁-C₄ alkyl acrylate-acrylic acid co-polymer;
(ix) a C₁-C₄ alkyl acrylate-methacrylic acid co-polymer;
(x) a C₁-C₄ alkyl methacrylate-acrylic acid co-polymer;
(xi) a C₁-C₄ alkyl methacrylate-methacrylic acid co-polymer;
(xii) a C₁-C₄ alkyl acrylate-acrylic acid-acrylamide co-polymer;
(xiii) a C₁-C₄ alkyl acrylate-methacrylic acid-acrylamide co-polymer;
(xiv) a C₁-C₄ alkyl methacrylate-acrylic acid-acrylamide co-polymer;
(xv) a C₁-C₄ alkyl methacrylate-methacrylic acid-acrylamide co-polymer;
(xvi) a C₁-C₄ alkyl acrylate-acrylic acid-methacrylamide co-polymer;
(xvii) a C₁-C₄ alkyl acrylate-methacrylic acid-methacrylamide co-polymer;
(xviii) a C₁-C₄ alkyl methacrylate-acrylic acid-methacrylamide co-polymer; and
(xix) a C₁-C₄ alkyl methaerylate-methacrylic acid-methacrylamide co-polymer.

Preferred cross-linking polymers include those given in the list above. The encaps are formed by reaction with a suitable monomer to form an insoluble shell. Most preferably the encaps are formed from melamine formaldehyde or urea formaldehyde condensates, as well as similar types of monomers, with the cross-linking polymers given above. Most preferably the shell comprises melamine formaldehyde.
Encapsulation can provide pore vacancies or interstitial openings depending on the encapsulation techniques employed.
The capsules for use in the invention have a perfume or perfume component core.
A carrier oil may also be present in the encaps core, in addition to the fragrance compound(s). These oils are hydrophobic materials that are miscible in the perfume materials used in the present invention, suitable oils are those having reasonable affinity for the fragrance chemicals. Suitable materials include, but are not limited to triglyceride oil, mono and diglycerides, mineral oil, silicone oil, diethyl phthalate, polyalpha olefins, castor oil and isopropyl myristate. Preferably, where present, the oil is a triglyceride oil, most preferably a capric/caprylic triglyceride oil.
For the liquid compositions of the invention, the capsules may be used in the form of a slurry, which preferably comprises about 40 % solids. The amount of such a 4C% solids. The amount of such a 40% capsule slurry to be used in a composition is up to 10%, preferably from 0.1 to 5%, more preferably from 1 to 2% by weight of the total composition.
When the encaps are in a powder or solid form the level is in the range of from 0.1 to 0.7 wt%, by weight of the total composition.
Particle size and average diameter of the capsules can vary from about 10 nanometers to about 1000 microns, preferably from about 50 nanometers to about 100 microns, more preferably from about preferably from about 2 to about 40 microns, even more preferably from about 4 to 15 microns. A particularly preferred range is from about 5 to 10 microns, for example 6 to 7 microns. The capsule distribution can be narrow, broad or multimodal. Multimodal distributions may be composed of different types of capsule chemistries.
The capsules can be combined with the composition at any time during the preparation of the laundry treatment composition. The capsules can be added to the composition or vice versa. For example, the capsules may be post dosed to a pre-made composition or may be combined with other ingredients such as water, during the preparation of the composition.

The Stabilising Active

The stabilizing active of the present invention is a mobile species which is capable of binding with weak acid groups. In the compositions of the invention, the weak acid groups bind with the stabilising active in preference to the fabric conditioning active.
The stabilising actives are selected from the group consisting of water soluble non-ester-linked cationic quaternary ammonium compounds, non-ionic surfactants and mixtures thereof, preferably non-ionic surfactants.
Suitable water soluble cationic quaternary ammonium compounds include single long chain ethoxylated cationic surfactant with a counter ion which is preferably an alkyl sulphate, such as methyl sulphate and ethyl sulphate, and most preferably is a methylsulphate counter-ion. The chains are not linked via ester groups.
The single long chain cationic surfactants alternatives are alkoxylated cationic quaternary ammonium surfactants. Those suitable for use in this invention are generally derived from fatty alcohols, fatty acids, fatty methyl esters, alkyl substituted phenols, alkyl substituted benzoic acids, and/or alkyl, substituted benzoate esters, and/or fatty acids that are converted to amines which can optionally be further reacted with another long chain alkyl or alkyl-aryl group; this amine compound is then alkoxylated with one or two alkylene oxide chains each having less than or equal to about 50 moles alkylene oxide moieties (e.g. ethylene oxide and/or propylene oxide) per mole of amine. Typical of this class are products obtained from the quaternization of aliphatic saturated or unsaturated, primary, secondary, or branched amines having one hydrocarbon chain from about 12 to about 22 carbon atoms alkoxylated with one or two alkylene oxide chains on the amine atom each having less than or equal to about 50 alkylene oxide moieties. The amine hydrocarbons for use herein have from about 12 to about 22 carbon atoms, and are preferably in a straight chain configuration. Suitable quaternary ammonium surfactants are made with one or two alkylene oxide chains attached to the amine moiety, in average amounts of less than or equal to about 50 moles of alkylene oxide per alkyl chain, more preferably from about 3 to about 20 moles of alkylene oxide, and most preferably from about 5 to about 12 moles of alkylene oxide per hydrophobic, e.g., alkyl group. Examples of suitable stabilizers of this type include Ethoquad® 18/25, C/25, and O/25 from Akzo and Variquat®-66 (soft tallow alkyl bis(polyoxyethyl) ammonium ethyl sulfate with a total of about 16 ethoxy units) from Goldschmidt.
Preferably, the compounds of the ammonium alkoxylated cationic surfactants have the following general formula:

{R1_m-Y- [(R2-O)_z-H]_p}⁺ X^-.

wherein R1 is selected from the group consisting of saturated or unsaturated, primary, secondary chain alkyl or alkyl-aryl hydrocarbons; said hydrocarbon chain having a length of from 12 to 22; each R2 is selected from the following groups or combinations of the following groups: -(CH₂)n- and/or - [CH(CH₃)CH_2]-; Y is selected from the following groups: = N⁺-(A)_q; -(CH₂)_n-N⁺-(A)_q; -B-(CH₂)_n-N⁺-(A)₂; - (phenyl) -N⁺-(A)_q; -(B-phenyl)-N⁺-(A)_q; with n being from about 1 to about 4.
Each A is independently selected from the following groups: H; R1; -(R2O)_z-H; -(CH₂)_xCH₃; phenyl, and substituted aryl; where 0 ≤ x ≤ about 3; and B is selected from the following groups : -O-; -NA-; -NA₂; -C(O)O-; and-C(O)N(A)-; wherein R2 is defined as hereinbefore; q = 1 or 2; and X^- is and m is from 1 to 4.
Preferred structures are those in which m = 1, p = 1 or 2, and 5 ≤ z ≤ 50, more preferred are structures in which m = 1, p = 1 or 2, and 7 ≤ z ≤ 20, and most preferred are structures in which m = 2, p = 1 or 2, and 9 < z ≤ 12.
Preferred examples are Benzalkonium Chloride (Barquat MB-50); ex LONZA
Water soluble quat are selected from mono-long chain quaternary ammonium compound of general formula R(R1)3N+X- or alkyl benzyl quaternary ammonium compound of a general formula R2R3(R4)2N+X-
Where R is selected from C8-C22 alkyl or alkenyl group R1 is selected from C1-C3 alkyl group, R2 is selected from C6-C18 alkyl or alkenyl group, R3 is benzyl group, R4 is selected from C1-C3 alkyl group, and X is an anion selected from chloride, bromide, iodide, nitrate, sulphate, methyl sulphate, ethyl sulphate, acetate and phosphate.
It is preferred that the water soluble quat of the present invention is either the alkyl benzyl quaternary ammonium chloride or the mono-long chain quaternary ammonium compound and most preferable the alkyl benzyl quaternary ammonium chloride.
The level of water soluble cationic ammonium compounds is suitably from 0.005 to 0.2 wt%.
Suitable non-ionic 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-(C₂H₄O)_z-CH₂-CH₂-OH

where R is selected from the group consisting of primary, secondary and branched chain alkyl and/or acyl hydrocarbyl groups; 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 11.
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.
Preferred examples are Lutensol AT25, a non-ionic surfactant; ex BASF and Genapol™ C200 (Clariant), which is based on coco chain and 20 EO groups.
The nonionic surfactant is present in an amount of from greater than 0.65 to 1.5%, more preferably, from 0.7 to 1% by weight, most preferably from 0.7 to 0.9% based on the total weight of the composition.

The Salt

Salts suitable for use in the compositions of the invention generally include any of the alkaline metals or alkaline earth metal salts of the mineral acids. NaCl, CaCl₂, MgCl₂ and similar salts of alkaline and alkaline earth meals are preferred and CaCl₂ is especially preferred. Generally, amounts of electrolyte salt needed are from 0.005 to 0.1 wt%, preferably from 0.01 to 0.07 wt%, by weight of the total composition.

Unconfined Perfume

The compositions of the invention preferably comprise one or more unconfined perfume, by which is meant a non-encapsulated perfume. Any suitable perfume or mixture of perfumes may be used. The perfume must be compatible with the carrier oil as described above and must be able to permeate the shell of the capsule. Those with skill in the art will appreciate that the present invention may contain a single ingredient, but it is much more likely that the present invention will comprise at least eight or more fragrance chemicals, more likely to contain twelve or more and often twenty or more fragrance chemicals. The present invention also contemplates the use of complex fragrance formulations containing fifty or more fragrance chemicals, seventy five or more or even a hundred or more fragrance chemicals in a fragrance formulation. Suitable unconfined perfumes for use in the present invention include those disclosed in EP1533364A2 (IFF).
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 0.2 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 logarithm to base 10 of the octanol/water partition coefficient (P). The octanol/water partition coefficient of a 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-Isopropylphenol, 3-Isopropylphenol, 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, mEthylphenol, (+)-Pulegone, 2,4-Dimethylbenzaldehyde, Isoxylaldehyde, Ethyl sorbate, Benzyl propionate, 1,3-Dimethylbutyl acetate, Isobutyl isobutanoate, 2,6-Xylenol, 2,4-Xylenal, 2,5-Xylenol, 3,5-Xylenol, Methyl cinnamate, Hexyl methyl ether, Benzyl ethyl ether, Methyl salicylate, Butyl propyl ketene, 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 of the present invention it is envisaged that there will be four or more, preferably five or more, more preferably six or more or even seven or more different perfume components from the list given of delayed blooming perfumes given above 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.

The Fabric Softening Composition

The conditioning agents are cationic.
The fabric softening compositions of the invention may be dilute or concentrated. Dilute products typically contain up to about 8%, preferably from 2 to 8% by weight of softening active, whereas concentrated products may contain from about 8 to about 50%, preferably from 8 to 25% by weight active. Compositions of more than about 25% by weight of active are defined as "super concentrated", depending on the active system, and are also intended to be covered by the present invention. The fabric conditioning agent may, for example, be used in amounts of from 0.5% to 35%, preferably from 2% to 30% more preferably from 5% to 25% and most preferably from 8% to 20% by weight of the composition.
The preferred softening active for use in rinse conditioner compositions of the invention is a quaternary ammonium compound (QAC). The quaternary ammonium fabric conditioners 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%, e.g. no more than 55%, or even no more than 45% 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):
wherein each R is independently selected from a C_5-35 alkyl or alkenyl group; R¹ represents a C_1-4 alkyl, C_2-9 alkenyl or a C_1-4 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-C₁₆ unsaturated fatty acids), ex Witco Corporation.
A second group of QACs suitable for use in the invention is represented by formula (II):
wherein each R¹ group is independently selected from C_1-4 alkyl, hydroxyalkyl or C_2-4 alkenyl groups; and wherein each R² group is independently selected from C_8-28 alkyl or alkenyl groups; and wherein n, T, and X^- are as defined above.
Preferred materials of this second group include 1,2 bis[tallowoyloxy]-3-trimethylammonium propane chloride, 1,2 bis[hardened tallowoyloxy]-3-trimethylammonium propane chloride, 1,2-bis[oleoyloxy]-3-trimethylammonium propane chloride, and 1,2 bis[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 C_1-4 alkyl, or C_2-4alkenyl groups; and wherein each R² group is independently selected from C_6-26 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 and hardened versions thereof.
In one embodiment, 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 comprise unsaturated fatty chains. Typical ester quat ratios of these materials are in the range of from 25 to 45% mono ester quat, from 45 to 60% diester quat and from 5 to 20% triester quat, preferably from 30 to 40% mono ester quat, from 50 to 55% diester quat and from 10 to 15% triester quat.
Iodine 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., 3a, 1136 (1962) Johnson and Shoolery.
Iodine value is defined as the number of grams of iodine absorbed per 100g of the test material. Olefinic materials absorb 1 gram of iodine per atom of olefinic hydrogen. Hence measurement can be converted to the equivalent Iodine Value. The hydrogen nmr spectrum at 360 MHz is obtained for the test material. The integral intensity, I_s, of the band derived from olefinic hydrogen in the alkyl chain and the integral intensity, I_m, of the band derived from terminal methyl groups in the alkyl chains are measured.
The number of olefinic hydrogens per molecule is given by: $\frac{I_{s}}{I_{m}} x 6$

and the Iodine Value is given by: $\frac{I_{3} x 127 x 100 x 6}{I_{m} x MMW}$

where MMW is the mean molecular weight of the test material.

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 autooxidation, with an attendant risk of yellowing of fabric. The present of a shading dye also reduces the risk of yellowing from this source.

Direct Dyes

Direct dyes (otherwise known as substantive dyes) are the class of water soluble dyes which have a 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;
R₁ is selected from: hydrogen and C1-C4-alkyl, preferably hydrogen;
R₂ 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 11, 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, an 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, Cl, 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 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, 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 11, 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.

Further Components

Co-softeners may be used. When employed, they are typically present at from 0.1 to 20% and particularly at from 0.3 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 of the present invention will preferably comprise a fatty complexing agent. Especially suitable fatty complexing agents include fatty alcohols.
Without being bound by theory it is believed that the fatty complexing material improves the viscosity profile of the composition by complexing with mono-ester component of the fabric conditioner material thereby providing a composition which has relatively higher levels of di-ester and tri-ester linked components. The di-ester and tri-ester linked components are more stable and do not affect initial viscosity as detrimentally as the mono-ester component.
It is also believed that the higher levels of mono-ester linked component present in compositions comprising quaternary ammonium materials based on TEA may destabilise the composition through depletion flocculation. By using the fatty complexing material to complex with the mono-ester linked component, depletion flocculation is significantly reduced.
In other words, the fatty complexing agent at the increased levels, as required by the present invention, "neutralises" the mono-ester linked component of the quaternary ammonium material. This in situ di-ester generation from mono-ester and fatty alcohol also improves the softening of the composition.
Preferred fatty alcohols include hardened tallow alcohol (available under the trade names Stenol™ and Hydrenol™, ex Cognis and Laurex™ CS, ex Albright and Wilson).
The fatty complexing agent is preferably present in an amount of greater than 0.1 to 10%, such as from 0.2 to 5% by weight based on the total weight of the composition. More preferably, the fatty component is present in an amount of from 0.3 to 4 weight %. The weight ratio of the mono-ester component of the quaternary ammonium fabric softening material to the fatty complexing agent is preferably from 10:1 to 1:10, more preferably from 20:1 to 1:20.
A preferred composition in accordance with the present invention comprises,

i) encapsulated perfume components,
ii) from 8 to 50 wt %, preferably from 8 to 20 wt % of a fabric softening active, which is an ester-linked triethanolamine quaternary ammonium compound comprising unsaturated fatty chains,
iii) from 0.65 to 1.5 wt %, preferably from 0.7 to 1 wt %, most preferably from 0.7 to 0.9 wt % of a stabilising active, which is a non-ionic surfactant,
iv) from 0.005 to 0.1 wt % of salt, which is CaCl₂ and
v) from greater than 0.3 to 5 % of tallow alcohol, wherein the encapsulates comprise a capsule wall having surface weak acid groups or moieties (and where weights are by the total weight of the composition).

Further Optional Ingredients

The compositions of 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, anti-oxidants, sunscreens, anti-corrosion agents, drape imparting agents, anti-static agents and ironing aids. The products of the invention preferably contain pearlisers and/or opacifiers.
It is believed that those polymers which deposit on cloth as a part of their activity may assist in the deposition of the photobleach and other perfume components present. These include cationic polymeric deposition aids. Suitable cationic polymeric deposition aids include cationic guar polymers such as Jaguar™ (ex Rhone Poulenc), cationic cellulose derivative such as Celquats™ (ex National Starch), Flocaid™ (ex National Starch), cationic potato starch such as SoftGel™ (ex Aralose), cationic polyacrylamides such as PCG (ex Allied Colloids).

Product Form

The compositions of the present invention are liquid rinse-added softening compositions suitable for use in a laundry process.
The compositions are liquids.
The liquid compositions have a pH ranging of about 2.5.
The formaldehyde level in the final product should be below 70 ppm, preferably below 15 ppm and most preferable below 10 ppm.
The active ingredient in the compositions is a fabric softening agent. More than one active ingredient may be included.
A composition for use in the invention is 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 watersoluble species, such as mineral salts or short chain (C_1-4) alcohols.
The compositions of the invention may also contain pH modifiers such as hydrochloric acid or lactic acid. The short chain alcohols include primary alcohols, such as ethanol, propanol, and butanol, and secondary alcohols such as isopropanol. The short chain alcohol may be added with the cationic softening agent during the preparation of the composition.
The composition is preferably a fabric softener or fabric conditioner composition, and 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, though less desirable, 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 of the compositions of the invention The compositions of the invention may be made by combining a melt comprising the fabric softening active with an aqueous phase comprising the encapsulated perfume components. Where the stabilising active may be melted with the fabric softening active, or it may be post dosed into the composition after combination of the melt and water phase. Salt is then added to obtain the desired viscosity.

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.

Example 1:- Preparation of Compositions 1, 2 and 3 in accordance with the invention, Comparative Examples A, B and C, and a control.

Preparation of Compositions A & B

1. The water was heated to 40°C with stirring.
2. Anti foam and preservative were then added.
3. The encap slurry was then added to the water phase and stirred for 2 minutes.
4. The fabric softening active and fatty complexing agent were melted and added to the water phase over 3-5 minutes.
5. Hydrochloric acid was then added to the desired pH and the dye was added to the mixture.
6. Free perfume was then added
7. CaCl₂ was added to obtain the desired viscosity then the product was cooled.

Preparation of Composition C

1. The water was heated to 40°C with stirring.
2. Anti foam and preservative were then added.
3. The encap slurry was then added to the water phase and stirred for 2 minutes.
4. The fabric softening active, fatty complexing agent and Genapol C200 were melted and added to the water phase over 3-5 minutes.
5. Hydrochloric acid was then added to the desired pH and the dye was added to the mixture.
6. Free perfume was then added
7. CaCl₂ was added to obtain the desired viscosity then the product was cooled.

Preparation of Composition D

1. The water was heated to 50°C with stirring.
2. Anti foam and preservative were then added.
3. The encap slurry was then added to the water phase and stirred for 2 minutes.
4. The fabric softening active, fatty complexing agent and Lutensol were melted and added to the water phase over 3-5 minutes.
5. Hydrochloric acid was then added to the desired pH and the dye was added to the mixture.
6. Free perfume was then added and the product was cooled

Preparation of Composition E

1. The water was heated to 40°C with stirring.
2. Anti foam and preservative were then added.
3. The encap slurry was then added to the water phase and stirred for 2 minutes.
4. The fabric softening active and fatty complexing agent were melted and added to the water phase over 3-5 minutes.
5. Hydrochloric acid was then added to the desired pH and the dye was added to the mixture.
6. Free perfume was then added and the product was cooled

Preparation of Compositions 1 & 2

1. The water was heated to 40°C with stirring.
2. Anti foam and preservative were then added.
3. The encap slurry was then added to the water phase and stirred for 2 minutes.
4. The fabric softening active, fatty complexing agent and Lutensol were melted and added to the water phase over 3-5 minutes.
5. Hydrochloric acid was then added to the desired pH and the dye was added to the mixture.
6. Free perfume was then added
7. CaCl2 was added to obtain the desired viscosity then the product was cooled.

Preparation of Composition 3

1.The water was heated to 40°C with stirring.
2. Anti foam and preservative were then added.
3. The encap slurry was then added to the water phase and stirred for 2 minutes.
4. The fabric softening active and fatty complexing agent were melted and added to the water phase over 3-5 minutes.
5. Hydrochloric acid was then added to the desired pH and the dye was added to the mixture.
6. Free perfume was then added.
7. Benzalkonium Chloride (BKC) was then added
8. CaCl₂ was added to obtain the desired viscosity then the product was cooled.

Preparation of the Control

1. The water was heated to 40°C with stirring.
2. Anti foam and preservative were then added.
3. The fabric softening active and fatty complexing were melted and added to the water phase over 3-5 minutes.
4. Hydrochloric acid was then added to the desired pH and the dye was added to the mixture.
5. Free perfume was then added.
6. CaCl₂ was added to obtain the desired viscosity then the product was cooled.

The resulting compositions are shown in Table 1 below.

Table 1: Compositions (wt%) of the liquid fabric softeners 1-3, A, B and Control (Cont).

Cmpn	Active¹	Free perfume²	Encap perfume LF₃	Encap perfume MF⁴	CaCl₂ ⁸	Lutensol AT25⁵	Genapol C200⁷	BKC⁶
A	10.5	1.7	0.5	-	0.014	-	-	-
B	10.5	1.7	-	0.5	0.017	-	-	-
C	10.5	1.7	0.5	-	0.014	-	0.175	-
D	10.5	1.7	0.5	-	-	0.75	-	-
E	10.5	1.7	0.5	-	-	-	-	-
1	10.5	1.7	0.5	-	0.02	0.75	-	-
2	13.1	1.7	0.5	-	0.0086	0.75	-	-
3	10.5	1.7	0.5	-	0.048	-	-	0.2
Cont	10.5	2.2	-	-	0.0057	0.0057	-	-

1 - VT90 - Tallow based soft TEA Quat; ex Stepan
2 - Free perfume oil; ex IFF
3 - Encapsulated perfume LF, low formaldehyde level in product, less than 10 ppm; ex IFF
4 - Encapsulated perfume MF, medium formaldehyde level in product, less than 70 ppm; ex IFF
5 - Lutensol AT25, a non-ionic surfactant; ex BASF
6 - Benzalkonium Chloride (Barquat MB-50); ex LONZA
7 - Genapol C200, non-ionic surfactant, ex Clariant
8 - CaCl₂, ex Aldrich

Each sample was placed into a "cup and bob" geometry and the viscosity continuously measured under shear at 1s^-1 for 60 seconds, followed by 60 seconds at 1000s^-1, followed by 60 seconds at 1s^-1, at 25°C. The difference between the viscosities at the end of the first low shear and at the end of the second low shear regions was calculated (designated "difference"). The percent difference between the viscosities at the end of the first low shear and at the end of the second low shear regions was also calculated (designated "percent difference").
The results are given in Table 2 below:- Table 2: Difference and percent difference between the viscosities at the end of the first low shear and at the end of the second low shear regions of the liquid fabric softeners 1, 2 and A-D.

Composition Difference Percent Difference

A 68 105

B 141 201

C 807 621

D 1790 213

E 5820 451

1 -2 -3

2 -1 -1%

3 25 3%

Control 9 7%
It will be seen that the presence of nonionic surfactant in combination with salt is critical for the stabilization of the encapsulate containing compositions. It will further be seen that the correct level of nonionic surfactant is also essential for successful stabilization to be achieved.

Example 2:- Preparation of Composition 3 in accordance with the invention, and Comparative Example F.

Preparation of Composition F

1. The water was heated to 40°C with stirring.
2. Anti foam and preservative were then added.
3. The encap slurry was then added to the water phase and stirred for 2 minutes.
4. The fabric softening active and fatty complexing agent were melted and added to the water phase over 3-5 minutes.
5. Hydrochloric acid was then added to the desired pH and the dye was added to the mixture.
6. Free perfume was then added
7. CaCl₂ was added then the product was cooled.

Preparation of Composition 4

1. The water was heated to 40°C with stirring.
2. Anti foam and preservative were then added.
3. The encap slurry was then added to the water phase and stirred for 2 minutes.
4. The fabric softening active and fatty complexing agent were melted and added to the water phase over 3-5 minutes.
5. Hydrochloric acid was then added to the desired pH and the dye was added to the mixture.
6. Free perfume was then added.
7. Benzalkonium Chloride (BKC) was then added
8. CaCl₂ was added then the product was cooled.

The resulting compositions are shown in Table 3 below.

Table 3: Compositions of the liquid fabric softeners 4 and E.

Composition	Active¹ (wt %)	Free perfume² (wt %)	Encapsulated perfume LF³ (wt %)	CaCl₂ ⁸ (wt %)	BKC⁶ (wt %)
F	10.5	1.7	0.5	0.011	-
4	10.5	1.7	0.5	0.011	0.2

1 - VT90 - Tallow based soft TEA Quat; ex Stepan
2 - Free perfume oil; ex IFF
3 - Encapsulated perfume LF, low formaldehyde level in product; ex IFF
6 - Benzalkonium Chloride (Barquat MB-50); ex LONZA
8 - CaCl₂, ex Aldrich

The physical properties of the compositions were measured as described above.
The results are given in Table 4 below:- Table 4: Viscosities of the liquid fabric softeners 3 and E.

Viscosity at 106s^-1

Time at 45°C (days) 0 6 22 29 33 41 53 81

F 57 36 19 19 23 20 27 >500

4 40 20 20 21 22 20 25 79
It will be seen that the time to solidification is greater in the composition in accordance with the invention.

Claims

A liquid softening composition comprising:
i) encapsulated perfume components,

ii) a fabric softening active, which is an ester-linked quaternary ammonium compound;

iii) a stabilising active selected from the group consisting of from 0.05 to 0.2 wt% by the total weight of the composition of water soluble non-ester-linked cationic quaternary ammonium compound(s), from 0.65 to 1.5 wt% by the total weight of the composition of non-ionic surfactant(s) and mixtures thereof, and

iv) from 0.005 to 0.1 wt% by the total weight of the composition of salt,
wherein the encapsulates comprise a capsule wall having surface weak acid groups, wherein the surface weak acid groups comprise carboxylate containing groups, represented by the formula (-C(OH)=O).
A composition as claimed in claim 1, wherein the level of non-ionic surfactant is from 0.7 to 0.9%.
A composition as claimed in any preceding claim, wherein the capsule wall comprises melamine formaldehyde or urea formaldehyde.
A composition as claimed in claim 3, wherein the capsule wall comprises melamine formaldehyde.
A composition as claimed in any preceding claim, wherein the capsule has a particle size of from about 5 to 10 microns.
A composition as claimed in any preceding claim, wherein the formaldehyde level is below 15 ppm.
A composition as claimed in any preceding claim, wherein the ester-linked compound is an ester-linked triethanolamine quaternary ammonium compound comprising unsaturated fatty chains.
A composition as claimed in any preceding claim, wherein the fabric softening active is present in an amount of from 8 to 50 wt%, by weight of the total composition.
A composition as claimed in any preceding claim, wherein the stabilising active is a non-ionic surfactant.
A composition as claimed in any preceding claim, wherein the salt is calcium chloride.
A composition as claimed in any preceding claim, which further comprises a fatty complexing agent.
A composition as claimed in claim 11, wherein the fatty complexing agent is tallow alcohol.
A composition as claimed in any preceding claim, which further comprises one or more unconfined perfume.
A composition as claimed in claim 13, wherein the perfume is present at a level of from 0.05 to 5% by weight, based on the total weight of the composition.
A method of stabilising a liquid fabric conditioning composition comprising encapsulated perfume components, a fabric softening active, which is an ester-linked quaternary ammonium compound and from 0.005 to 0.1 wt% by the total weight of the composition of salt, wherein the encapsulates comprise a capsule wall having surface weak acid groups, comprising the step of adding a stabilising active selected from the group consisting of from 0.05 to 0.2 wt% by total weight of the composition of water soluble non-ester-linked cationic quaternary ammonium compounds, from 0.65 to 1.5 wt% by total weight of the composition of non-ionic surfactants and mixtures thereof to the composition, wherein the surface weak acid groups comprise carboxylate containing groups, represented by the formula (-C(OH)=O).