EP2294167B1

EP2294167B1 - Improvements relating to fabric conditioners

Info

Publication number: EP2294167B1
Application number: EP09761580.1A
Authority: EP
Inventors: Richard Edward Bentley; Ian David Charlton
Original assignee: Unilever PLC; Unilever NV
Current assignee: Unilever PLC; Unilever NV
Priority date: 2008-06-11
Filing date: 2009-05-20
Publication date: 2016-06-22
Anticipated expiration: 2029-05-20
Also published as: CN102057028A; BRPI0915359B1; AR072079A1; WO2009150017A1; BRPI0915359A2; ZA201008203B; ES2592692T3; EP2294167A1; CN102057028B

Description

TECHNICAL FIELD

The present invention concerns a process for the preparation of encapsulated perfume in fabric softener compositions.

BACKGROUND OF THE INVENTION

The use of encapsulated perfume components (encaps) in fabric conditioners is advantageous in that it enables the 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 by protecting the perfume in the capsule.
The encaps themselves are relatively fragile and contain volatile perfume components which are depleted if rupture of the encap casing occurs. Accordingly, in a typical method of manufacture, the encaps are introduced into the active mixture at a late stage of the process in order to preserve them. Typically, water and minor ingredients such as antifoam and preservative are heated whilst the softening active is melted separately. The molten active is then added to the hot water with agitation before being allowed to cool. Only then is the encapsulated perfume added to the mixture, along with any free perfume oil. Such a sequence of steps, with the addition of the encaps taking place after the addition of the molten active to the water phase, helps to preserve the fragile encaps and minimises damage to these relatively delicate components.
However problems persist with poor dispersion of the encaps in the final product, which leads to aggregation. The result is poor visual appearance, and non-consistent performance.
WO 2007/028495 relates to aqueous conditioning compositions comprising benzalkonium chloride, calcium chloride and fatty acid. These compositions are characterised by excellent long term stability when prepared by a method wherein a slurry of encapsulated perfume is added to the charge water, followed by the addition of ester-comprising water-insoluble quaternary ammonium fabric conditioning agent and free perfume, at a temperature below the phase transition temperature of the compositions.
There remains a need for ways of introducing encaps into compositions such as fabric conditioner compositions, which allows acceptable dispersion of the encaps in the final composition, where the compositions are free from calcium chloride and benzalkonium chloride.
Surprisingly we have now found that adding the encaps to the water phase, before the addition of the molten active phase, gives good dispersion and corresponding good visual properties and consistent high performance, without any significant damage occurring to the encaps.

STATEMENT OF THE INVENTION

In a first aspect of the invention there is provided a process for preparing a composition comprising an ester-linked quaternary ammonium fabric softening active, an encapsulated perfume and a non-confined perfume, wherein the process comprises the step of dispersing the encapsulated perfume in water, before the addition of the fabric softening active to the water, and wherein the composition is free from calcium chloride and benzalkonium chloride.
In a second aspect of the invention, there is provided a composition obtained from the process of the first aspect of the invention.

DETAILED DESCRIPTION OF THE INVENTION

The Process

In the process of the invention, the encapsulated perfume is added to the water phase, before the addition of the molten active. The water phase may also contain minor components such as preservatives and antifoam.
The proportion of the encapsulated perfume that is added to the water phase prior to the addition of the molten active should be from about 20 to 100 %, preferably from 50 to 100 %, more preferably from 80 to 100, most preferably 100 %.
Non-confined perfume oil is added in the conventional way, after the active and water, phases have been combined and cooled.
A preferred process of the invention comprises the steps of:-

1) mixing perfume encaps, and optional minors such as preservatives and anti-foam, with heated water to form a water phase;
2) melting the fabric softening active to form a melt;
3) combining the water phase and the melt with agitation;
4) allowing the resulting mixture to cool; and
5) adding any non-confined perfume oil to the cooled mixture.

The molten active is added to the water phase, wherein the water phase contains perfume encapsulates. It is preferable that 100 % of the molten active is added at this stage, although the addition of a minor amount of molten active to the water phase before the encaps are added is also covered by the present invention. By minor amount is meant, for example, from 0.0001 to 25 %, for example 20, or 10 %.

The Quaternary Ammonium Compound

The softening active for use in the process and compositions of the invention is an ester-linked quaternary ammonium compound.
Preferred ester-linked quaternary ammonium compounds for use in the process of the invention have unsaturated chains, i.e. are the so-called "soft" quats. Such compounds are typically derived from fatty acyl or fatty acid feed stock having an Iodine Value of from 20 to 140, preferably from 20 to 60, more preferably from 20 to 50, most preferably from 25 to 45. The unsaturated chains come from the unsaturated fatty feed stock.
If there is a mixture of quaternary ammonium materials present in the composition, the iodine value, referred to above, represents the mean iodine value of the parent fatty acyl compounds or fatty acids of all of the quaternary ammonium materials present. Likewise, if there is any saturated quaternary ammonium quaternary ammonium materials present in the composition, the iodine value, referred to above, represents the mean iodine value of the parent fatty acyl compounds or fatty acids of all of the quaternary ammonium materials present.
Iodine value is defined as the number of grams of iodine absorbed per 100 g of test material. NMR spectroscopy is a suitable technique for determining the iodine value of the softening agents of the present invention, using the method described in Anal. Chem., 34, 1136 (1962) by Johnson and Shoolery and in EP 593,542 (Unilever, 1993 ).
The quaternary ammonium compound is preferably present in the compositions of the invention at a level of from 8 % to 20 %, preferably from 10 % to 15 %, for example from 8 to 16 % by weight of the total composition. The compositions of the invention are preferably concentrated fabric conditioners.
Particularly preferred materials are the ester-linked triethanolammonium (TEA) quaternary ammonium compounds comprising a mixture of mono-, di- and tri-ester linked components.
Typically, such TEA-based fabric softening compounds comprise a mixture of mono, di- and tri-ester forms of the compound. Typically 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):

[(CH₂)_n(TR)]_m-(R¹).N⁺ - [(CH₂)_n(OH)]_3-m X^- (I)

wherein each R is independently selected from a C_5-35 alkyl or alkenyl group; R¹ represents a C_1-4 alkyl, C_2-4 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 Tetranyl™ ex Kao, AT-1 (di-[tallow ester] of triethanolammonium methylsulphate), and L5/90 (di-[palm ester] of triethanolammonium methylsulphate), both ex Kao, and Rewoquat™ WE15 (a di-ester of triethanolammonium methylsulphate having fatty acyl residues deriving from C₁₀-C₂₀ and C₁₆-C₁₈ unsaturated fatty acids), ex Witco Corporation and the Stepantex (ex Stepan) soft range, Stepantex VT90, VA90 and SP90.
A second group of quaternary ammonium compounds suitable for use in the invention is represented by formula (II):

(R¹)₃N⁺-(CH₂)_n-CH. (CH₂TR²)-TR² X^- (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 and 1,2-bis[oleoyloxy]-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.

Encaps

The compositions derived from the process of the present invention comprise one or more perfumes. The perfume is present in encapsulated and non-confined forms. The total amount of encapsulated and non-confined perfume present is preferably an amount of 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 0.5 to 3.0 % by weight, based on the total weight of the composition. The amount of encaps present is from 0.01 to 0.9 %, preferably from 0.05 to 0.7 %, more preferably from 0.15 to 0.5 % and most preferably from 0.2 to 0.5 % by weight of the total composition.
The encapsulated perfume is preferably in the form of a slurry having a viscosity of from greater than water to 1000 cps at 21 s^-1 and 25 °C.
The perfume loading of the encaps, that is to say the amount of the total encap weight that is perfume, is preferably from 20 to 40 wt %, more preferably from 28 to 32 wt %, by total weight of the encaps.
The encaps (or "capsules") for use in the process of the present invention comprise a shell. The shell is preferably comprised of materials including aminoplasts, proteins, polyurethanes, polysaccharides, gums, celluloses, and any other encapsulating material which may be used effectively in the present invention, such as polymethylmethacrylate. Preferred encapsulating polymers include those formed from melamine formaldehyde or urea formaldehyde condensates, as well as similar types of aminoplasts. Most preferably the shell comprises melamine formaldehyde.
Additionally, microcapsules made via the simple or complex coacervation of gelatin are also preferred for use with the coating. Microcapsules having shell walls comprised of polyurethane, polyamide, polyolefin, polysaccaharide, protein, silicone, lipid, modified cellulose, gums, polyacrylate, polystyrene, and polyesters or combinations of these materials are also possible.
A representative process used for aminoplast encapsulation is disclosed in U.S. Patent No. 3,516,941 though it is recognized that many variations with regard to materials and process steps are possible. A representative process used for gelatin encapsulation is disclosed in U.S. Patent No, 2,800,457 though it is recognized that many variations with regard to materials and process steps are possible. Both of these processes are discussed in the context of fragrance encapsulation for use in consumer products in U.S. Patent Nos. 4,145,184 and USA 5,112,688 respectively.
Encapsulation can provide pore vacancies or interstitial openings depending on the encapsulation techniques employed.
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 urea-formaldehyde pre-condensate or a melamine-formaldehyde pre-condensate.
Microcapsule formation using mechanisms similar to the foregoing mechanism, using (i) melamine-formaldehyde or urea-formaldehyde pre-condensates and (ii) polymers containing substituted vinyl monomeric units having proton-donating functional group moieties (e.g. sulfonic acid groups or carboxylic acid anhydride groups) bonded thereto is disclosed in U.S. Patent 4,406,816 (2-acrylamido-2-methyl-propane sulfonic acid groups), UK published Patent Application GB 2,062,570 A (styrene sulfonic acid groups) and UK published Patent Application GB 2,006,709 A (carboxylic acid anhydride groups).
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 3 to 30 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.

Perfume

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.
It is 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.

Suitable non-encapsulated perfume ingredients include 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-Xylenol, 2,5-Xylenol, 3,5-Xylenol, Methyl cinnamate, Hexyl methyl ether, Benzyl ethyl ether, Methyl salicylate, Butyl propyl ketone, Ethyl amyl ketone, Hexyl methyl ketone, 2,3-Xylenol, 3,4, Xylenol, Cyclopentadenanolide and Phenyl ethyl 2 phenylacetate 2.
It is commonplace for a plurality of perfume components to be present in a formulation.
Another group of perfumes with which the present invention can be applied are the so-called 'aromatherapy' materials. These include many components also used in perfumery, including components of essential oils such as Clary Sage, Eucalyptus, Geranium, Lavender, Mace Extract, Neroli, Nutmeg, Spearmint, Sweet Violet Leaf and Valerian.

Further Components

Co-softeners may be used. When employed, they are typically present at from 0.1 to 20% and particularly at from 0.5 to 10%, based on the total weight of the composition. Preferred co-softeners include fatty esters, and fatty N-oxides. Fatty esters that may be employed include fatty monoesters, such as glycerol monostearate, fatty sugar esters, such as those disclosed WO 01/46361 (Unilever ).
The compositions of the present invention will preferably comprise a fatty alcohol.
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 acids include hardened tallow fatty acid (available under the trade name Pristerene™, ex Uniqema).
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 greater than 0.3 to 5% by weight based on the total weight of the composition. More preferably, the fatty component is present in an amount of from 0.4 to 4%. The weight ratio of the mono-ester component of the quaternary ammonium fabric softening material to the fatty complexing agent is preferably from 5:1 to 1:5, more preferably 4:1 to 1:4, most preferably 3:1 to 1:3, e.g. 2:1 to 1:2.
The compositions may further comprise a nonionic surfactant, especially where the level of quaternary ammonium compound is above about 8 % by weight of the total composition. Typically these can be included for the purpose of stabilising the compositions.
Suitable nonionic surfactants include addition products of ethylene oxide and/or propylene oxide with fatty alcohols, fatty acids and fatty amines. Any of the alkoxylated materials of the particular type described hereinafter can be used as the nonionic surfactant.
Suitable surfactants are substantially water soluble surfactants of the general formula:

R-Y-(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. Genapol™ C200 (Clariant) based on coco chain and 20 EC groups is an example of a suitable nonionic surfactant.
Where present, the nonionic surfactant is present in an amount from 0.01 to 10%, more preferable C.1 to 5 by weight, based on the total weight of the composition.
Alternative stabilising agents may be used. Alternative stabilisers 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 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.
Another class of possible alternatives to non-ionic stabilisers are the long chain cationic surfactants based on quaternized amido-amine surfactants of the general structure;

R1-C(:O)-NH-[C(R2)(R3)]_n-N(CH₃) (R4) (R5)⁺ X^-

in which R1 = C12-30-alkyl, -alkenyl, -arylalkyl, and - (cycloalkyl)alkyl; R2 and R3 = H or C1-4-alkyl; R4 and R5 = C1-4-alkyl, -alkoxyalkyl, and -hydroxyalkyl; X- is a halide or methylsulphate anion, preferably a methylsulphate anion counterion and n = 1-10.
Preferred commercial surfactants include Rewoquat V3351, a tallow alkyl amido-amine methyl sulphate quat (ex Goldschmidt), Surfac ARF, a tallow amine ethoxy ammonium methyl sulphate (ex Surfachem).
The amido-amine single long chain cationic surfactants for use in the present invention may be alkoxylated. These alkoxylated amido-amine single chain cationic surfactants comprise one or more 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. The preferred alkoxylated surfactants for use in the present invention comprise at least one ethoxylate group.
Yet other class of possible alternatives are given WO 95/27771 and include amphoteric surfactants including betaines and tegobetaines.

Further Optional Ingredients

The compositions of the invention may contain one or more other ingredients. Such ingredients include photobleaches, fluorescent agents, dyes, preservatives (e.g. bactericides), pH buffering agents, preferably inorganic or organic based such as hydrochloric acid, lactic acid and sodium lactate, etc, 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.
It is believed that those polymers which deposit on cloth as a part of their activity may assist in the deposition of 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 derivatives 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

A composition for use in the invention may be in solid or liquid form. The composition may be a concentrate to be diluted, rehydrated and/or dissolved in a solvent, including water, before use. The composition may also be a ready-to-use (in-use) composition. Preferably the composition is provided as a ready to use liquid comprising an aqueous phase. The aqueous phase may comprise water-soluble species, such as mineral salts or short chain (C_1-4) alcohols.
The mineral salts may aid the attainment of the required phase volume for the composition, as may water soluble organic salts and cationic deflocculating polymers, as described in EP 41,698 A2 (Unilever ). Such salts may be present at from 0.001 to 1% and preferably at from 0.005 to 0.1% by weight of the total composition. Examples of suitable mineral salts for this purpose include calcium chloride and magnesium chloride. The compositions of the invention may also contain pH modifiers such as hydrochloric 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, being a fabric softener or fabric conditioner composition, is preferably for use in the rinse cycle of a home textile laundering operation, where, it may be added directly in an undiluted state to a washing machine, e.g. through a dispenser drawer or, for a top-loading washing machine, directly into the drum. Alternatively, it can be diluted prior to use. The compositions may also be used in a domestic hand-washing laundry operation.

EXAMPLES

Embodiments of the invention are now illustrated with reference to the following non-limiting examples. Unless stated otherwise, all proportions are given in weight percent by weight of the total composition.

Example 1: Preparation of Composition 1 and Comparative Example A

In the following examples, where perfume encaps were used as a slurry, sufficient slurry was added to reach 0.5 % encapsulated perfume within the final formulation.

Composition 1 and Comparative Example A both have the same composition but Composition 1 was prepared using the process of the invention, whilst Comparative Example A was prepared using the process of the prior art.

Ingredients	Composition 1 (wt %, by weight of total composition)	Comparative Example A (wt %, by weight of total composition)
Water	85	85
Minors (antifoam, preservative, dye and pH buffer)	1	1
Perfume encaps³	2	2
Free perfume²	1	1
softening active¹	11	11
HCl	to stable pH	to stable pH

¹Softening active is Stepantex UL90 (Stepan)
²Free perfume oil is Azure (IFF)
³Encapsulated perfume slurry is Blue Touch (IFF)

Preparation of Composition 1

1. The water was heated to 65°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 was 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. The resulting product was then milled until the required viscosity had been reached.
7. The product was then cooled to 45°C.
8. Free perfume was then added to the cooled product.

Preparation of Comparative Example A

1. The water was heated to 65°C with stirring.
2. Anti foam and preservative were then added.
3. The fabric softening active was 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. The resulting product was then milled until the required viscosity had been reached.
6. The product was then cooled to 45°C.
7. The encap slurry and free perfume were then added to the cooled mixture.

The resulting compositions were studied using light microscopy to assess dispersion of the encaps in the compositions. The comparative example had poor visual properties with significant aggregation of the encaps. In contrast, the composition according to the invention showed minimal aggregation and had excellent visual appearance. Further, it was noted that the viscosity properties were not affected in Composition 1 and no damage to the encaps was apparent.

Claims

A process for preparing a composition comprising an ester-linked quaternary ammonium fabric softening active, an encapsulated perfume and a non-confined perfume, wherein the process comprises the step of dispersing the encapsulated perfume in water before the addition of the fabric softening active to the water, and wherein the composition is free from calcium chloride and benzalkonium chloride.
A process as claimed in claim 1, wherein the proportion of fabric softening active that is added to the water after the dispersion of the encapsulated perfume is 100%.
A process as claimed in claim 1 or claim 2, wherein the level of encapsulated perfume that is dispersed in water, before the addition of the fabric softening active is from 20 to 100%, preferably from 50 to 130%, more preferably from 80 to 100, most preferably 100%, by weight of the total amount of encapsulates.
A process as claimed in any preceding claim, wherein the fabric softening active is derived from fatty acyl or fatty acid feed stock having an Iodine Value of from 20 to 60.
A process as claimed in any preceding claim, wherein the fabric softening active is present in the composition at a level of from 8 % to 16 %, by weight of the total composition.
A process as claimed in any preceding claim, wherein the encapsulated and non-confined perfume is present in a total amount of from 0.01 to 10 % by weight of the total composition.
A process as claimed in any preceding claim, wherein the encapsulated perfume is present in an amount of from 0.15 to 0.5 % by weight of the total composition.
A process as claimed in any preceding claim, wherein the encapsulated perfume is in the form of a slurry having a viscosity of from greater than water to 1000 cps at 21 s^-1 and 25 °C.
A process as claimed in any preceding claim, wherein the composition further comprises at least one pH buffering agent.
A process as claimed in any preceding claim, which comprises the steps of:-
1) mixing perfume encaps, and optional minors such as preservatives and anti-foam, with heated water, to form a water phase;

2) melting the fabric softening active to form a melt;

3) combining the water phase and the melt with agitation;

4) allowing the resulting mixture to cool; and

5) adding any non-confined perfume oil to the cooled mixture.
A composition obtained from the process of any one of the preceding claims.