EP4377430A1

EP4377430A1 - Method of producing a fabric conditioner

Info

Publication number: EP4377430A1
Application number: EP22747330.3A
Authority: EP
Inventors: Leandro Augusto de Paula EDUARDO; Thatiana Guisolphe CASTRO
Original assignee: Unilever Global IP Ltd; Unilever IP Holdings BV
Current assignee: Unilever Global IP Ltd; Unilever IP Holdings BV
Priority date: 2021-07-26
Filing date: 2022-07-08
Publication date: 2024-06-05
Also published as: WO2023006384A1; CN117716010A

Abstract

A method for the production of a fabric conditioner, wherein the method comprises the steps of: a) Production of a premix comprising fabric softening active and perfume; b) Optionally storing the premix and/or transporting the premix to a different geographical location; c) Diluting the premix in water; d) Separately dispersing a rheology modifier in water; and e) 5 Mixing the diluted premix and dispersed rheology modifier.

Description

Method of producing a fabric conditioner

Field of the invention

The present invention is in the field of manufacture of fabric conditioner compositions.

Background of the invention

Fabric conditioner compositions are traditionally formulated in a single process at a single factory, then packaged and distributed. This generally occurs at a central factory and the packaged product is shipped great distances. Alternatively multiple smaller factories may produce fabric conditioners; however it is burdensome on smaller factories to produces multiple variants (e.g. fabric conditioners having different fragrances and/or different concentrations of active materials). Neither of these solutions are optimal, therefore a new method of production is required. However the production of a fabric conditioner is a sensitive process, particularly when polymers and microcapsules are involved, which tend to effect viscosity or can make the product separate. There remains a need for improved, more versatile methods of manufacturing fabric conditioners.

Summary of the invention

It has been found that the method described herein allows for the production of a concentrated fabric conditioner premix which can either be shipped to local factories for dilution or stored and diluted when required. By following the method described herein, a stable composition can be produced.

Accordingly in one aspect of the present invention is provided a method for the production of a fabric conditioner, wherein the method comprises the steps of: a. Production of a premix comprising fabric softening active and perfume; b. Optionally storing the premix and/or transporting the premix to a different geographical location; c. Diluting the premix in water; d. Separately dispersing a rheology modifier in water; e. Mixing the diluted premix and the dispersed rheology modifier. Detailed description

These and other aspects, features and advantages will become apparent to those of ordinary skill in the art from a reading of the following detailed description and the appended claims. For the avoidance of doubt, any feature of one aspect of the present invention may be utilised in any other aspect of the invention. The word “comprising” is intended to mean “including” but not necessarily “consisting of” or “composed of.” In other words, the listed steps or options need not be exhaustive. It is noted that the examples given in the description below are intended to clarify the invention and are not intended to limit the invention to those examples per se. Similarly, all percentages are weight/weight percentages unless otherwise indicated. Except in the operating and comparative examples, or where otherwise explicitly indicated, all numbers in this description indicating amounts of material or conditions of reaction, physical properties of materials and/or use are to be understood as modified by the word “about”. Numerical ranges expressed in the format "from x to y" are understood to include x and y. When for a specific feature multiple preferred ranges are described in the format "from x to y", it is understood that all ranges combining the different endpoints are also contemplated. a. Production of a premix comprising fabric softening active and perfume;

In the first step of the process a premix is produced. Preferably the premix comprises a fabric softening active and water. More preferably the premix comprises a fabric softening active, perfume ingredients and water.

To produce the premix, preferably the fabric softening active is melted to form a pre-melt then added to any other ingredients. Preferably the fabric softening active melt is formed at a temperature above 50°C, more preferably above 55°C. The melted fabric softening active is then added to a mixture of water. The water is preferably at a temperature of about 40°C to about 60°C. The other ingredients may be mixed in the water before and/or after the fabric softening active is added. Preferably any encapsulated perfume or non-ionic surfactant present is dispersed in the water prior to the fabric softening active being added. The mixture is then cooled. It may be preferable to add some ingredients after the mixture has started to cool. Preferably any free perfume present in the composition is added after the composition has cooled to 40°C or bellow.

The viscosity of the premix is preferably 400 to 800 mPa.s-1, more preferably 500 to 750 mPa.s-1. Viscosity is measured at Thermo Scientific Haake Viscotester 550 model with a MV1 Sensor System for 15 seconds using 106 viscosity range with temperature of 25°C. The premix preferably comprises a fabric softening active. Preferably the premix comprises more than 5 wt. % fabric softening active, more preferably more than 8 wt. % fabric softening active, most preferably more than 10 wt. % fabric softening active by weight of the premix. Preferably the premix of the present invention comprises less than 60 wt. % fabric softening active, more preferably less than 40 wt. % fabric softening active, most preferably less than 35 wt. % fabric softening active by weight of the premix. Suitably the premix comprises 5 to 60 wt. % fabric softening active, preferably 8 to 40 wt.% fabric softening active and more preferably 10 to 35 wt. % fabric softening active by weight of the premix.

The fabric softening active may be any material known to soften fabrics. These may be polymeric materials or compounds known to soften materials. Examples of suitable fabric softening actives include: quaternary ammonium compounds, silicone polymers, polysaccharides, clays, amines, fatty esters, dispersible polyolefins, polymer latexes and mixtures thereof.

The fabric softening actives may preferably be cationic or non-ionic materials. Preferably, the fabric softening actives of the present invention are cationic materials. Suitable cationic fabric softening actives are described herein.

The preferred softening actives for use in the premix of the invention are quaternary ammonium compounds (QAC).

The QAC preferably comprises at least one chain derived from fatty acids, more preferably at least two chains derived from fatty acids. Generally fatty acids are defined as aliphatic monocarboxylic acids having a chain of 4 to 28 carbons. Fatty acids may be derived from various sources such as tallow or plant sources. Preferably the fatty acid chains are derived from plants. Preferably the fatty acid chains of the QAC comprise from 10 to 50 wt. % of saturated C18 chains and from 5 to 40 wt. % of monounsaturated C18 chains by weight of total fatty acid chains. In a further preferred embodiment, the fatty acid chains of the QAC comprise from 20 to 40 wt. %, preferably from 25 to 35 wt. % of saturated C18 chains and from 10 to 35 wt. %, preferably from 15 to 30 wt. % of monounsaturated C18 chains, by weight of total fatty acid chains.

The preferred quaternary ammonium fabric softening actives for use in compositions of the present invention are ester linked quaternary ammonium compounds or 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 wt.% of the fabric softening compound, preferably no more than 60 wt.% e.g. no more than 55%, or even no more that 45% of the fabric softening compound and at least 10 wt.% 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 C5 to C35 alkyl or alkenyl group; R1 represents a C1 to C4 alkyl, C2 to C4 alkenyl or a C1 to C4 hydroxyalkyl group; T may be either O-CO. (i.e. an ester group bound to R via its carbon atom), or 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 methylsulfate. 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.

Suitable actives include soft quaternary ammonium actives such as Stepantex VT90, Rewoquat WE18 (ex-Evonik) and Tetranyl L1/90N, Tetranyl L190 SP and Tetranyl L190 S (all ex-Kao).

Also suitable are actives rich in the di-esters of triethanolammonium methylsulfate, otherwise referred to as "TEA ester quats".

Commercial examples include Praepagen™ TQL (ex-Clariant), and Tetranyl™ AHT-1 (ex- Kao), (both di-[hardened tallow ester] of triethanolammonium methylsulfate), AT-1 (di-[tallow ester] of triethanolammonium methylsulfate), and L5/90 (di-[palm ester] of triethanolammonium methylsulfate), (both ex-Kao), and Rewoquat™ WE15 (a di-ester of triethanolammonium methylsulfate having fatty acyl residues deriving from C10-C20 and C16-C18 unsaturated fatty acids) (ex-Evonik). A second group of QACs suitable for use in the invention is represented by formula (II): wherein each R1 group is independently selected from C1 to C4 alkyl, hydroxyalkyl or C2 to C4 alkenyl groups; and wherein each R2 group is independently selected from C8 to C28 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):

(R ' JsrN ^*-KCH₂)„-T-R²)₂ X (III) wherein each R1 group is independently selected from C1 to C4 alkyl, or C2 to C4 alkenyl groups; and wherein each R2 group is independently selected from C8 to C28 alkyl or alkenyl groups; and n, T, and X- are as defined above. Preferred materials of this third group include bis(2-tallowoyloxyethyl)dimethyl ammonium chloride, partially hardened and hardened versions thereof.

A particular example of the fourth group of QACs is represented the by the formula: A fourth group of QACs suitable for use in the invention are represented by formula (V)

R1 and R2 are independently selected from C10 to C22 alkyl or alkenyl groups, preferably C14 to C20 alkyl or alkenyl groups. X- is as defined above.

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 methylsulfate. Such ester- linked triethanolamine quaternary ammonium compounds comprise unsaturated fatty chains.

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 the quaternary ammonium materials present. Likewise, if there are any saturated quaternary ammonium materials present in the composition, the iodine value represents the mean iodine value of the parent acyl compounds of fatty acids of all of the quaternary ammonium materials present.

Iodine value as used in the context of the present invention refers to, the fatty acid used to produce the QAC, the measurement of the degree of unsaturation present in a material by a method of nmr spectroscopy as described in Anal. Chem. , 34, 1136 (1962) Johnson and Shoolery.

A further type of softening compound may be a non-ester quaternary ammonium material represented by formula (VI): wherein each R1 group is independently selected from C1 to C4 alkyl, hydroxyalkyl or C2 to C4 alkenyl groups; R2 group is independently selected from C8 to C28 alkyl or alkenyl groups, and X- is as defined above.

The premix further comprises perfume ingredients. The perfume ingredients may be a free oil perfume and/or perfume microcapsules.

Preferably the premix comprises 0.1 to 30 wt.% perfume ingredients, more preferably 0.2 to 20 wt.% perfume ingredients, most preferably 0.5 to 15 wt. % perfume ingredients by weight of the premix. By perfume ingredients it is meant the combined free perfume and any encapsulated perfume.

Useful perfume components may 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.

Particularly preferred perfume components are blooming perfume components and substantive perfume components. Blooming perfume components are defined by a boiling point less than 250°C and a LogP greater than 2.5. Substantive perfume components are defined by a boiling point greater than 250°C and a LogP greater than 2.5. Preferably a perfume composition will comprise a mixture of blooming and substantive perfume components. The perfume composition may comprise other perfume components.

It is commonplace for a plurality of perfume components to be present in a perfume composition. In the compositions for use in the present invention it is envisaged that there will be three or more, preferably four or more, more preferably five or more, most preferably six or more different perfume components. An upper limit of 300 perfume ingredients may be applied. Free perfume may preferably be present in an amount from 0.01 to 28 wt. %, more preferably 0.1 to 20 wt.%, more preferably from 0.1 to 15 wt.%, even more preferably from 0.1 to 10 wt.%, most preferably from 0.2 to 6 wt. %, based on the total weight of the composition.

Preferably some of the perfume components are contained in a microcapsule. Suitable encapsulating materials may comprise, but are not limited to; aminoplasts, proteins, polyurethanes, polyacrylates, polymethacrylates, polysaccharides, polyamides, polyolefins, gums, silicones, lipids, modified cellulose, polyphosphate, polystyrene, polyesters or combinations thereof.

Perfume components contained in a microcapsule may comprise odiferous materials and/or pro-fragrance materials.

Particularly preferred perfume components are as described for free perfumes.

Encapsulated perfume may preferably be present in an amount from 0.01 to 25 wt.%, more preferably 0.05 to 20 wt. %, more preferably from 0.05 to 15 wt.%, even more preferably from 0.1 to 10 wt.%, most preferably from 0.1 to 6 wt.%, based on the total weight of the premix.

The premix preferably comprises non-ionic surfactants. 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 (VII): R-Y-(C₂H40)_Z-CH2-CH2-0H (VII) 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(0)0- , -C(0)N(R)- or -C(0)N(R)R- in which R has the meaning given above for formula (VII), 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 EO groups is an example of a suitable nonionic surfactant.

A class of preferred non-ionic surfactants include addition products of ethylene oxide and/or propylene oxide with fatty alcohols, fatty acids and fatty amines. These are preferably selected from addition products of (a) an alkoxide selected from ethylene oxide, propylene oxide and mixtures thereof with (b) a fatty material selected from fatty alcohols, fatty acids and fatty amines.

Suitable surfactants are substantially water soluble surfactants of the general formula (VIII): R-Y-(C2H40)z-CH2-CH2-0H (VIII) where R is selected from the group consisting of primary, secondary and branched chain alkyl and/or acyl hydrocarbyl groups (when Y = -C(0)0, R ¹ an acyl hydrocarbyl group); primary, secondary and branched chain alkenyl hydrocarbyl groups; and primary, secondary and branched chain alkenyl-substituted phenolic hydrocarbyl groups; the hydrocarbyl groups having a chain length of from 10 to 60, preferably 10 to 25, e.g. 14 to 20 carbon atoms.

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

-O- , -C(0)0- , -C(0)N(R)- or -C(0)N(R)R- in which R has the meaning given above for formula (VIII), or can be hydrogen; and Z is at least about 6, preferably at least about 10 or 11.

Lutensol™ AT25 (BASF) based on C16:18 chain and 25 EO groups is an example of a suitable non-ionic surfactant. Other suitable surfactants include Renex 36 (Trideceth-6), ex Croda; Tergitol 15-S3, ex Dow Chemical Co.; Dihydrol LT7, ex Thai Ethoxylate ltd; Cremophor CO40, ex BASF and Neodol 91-8, ex Shell.

Non-ionic surfactants may preferably be present in an amount from 0.001 to 10 wt.%, more preferably 0.005 to 5 wt. %, more preferably from 0.01 to 3 wt.%, most preferably from 0.05 to 1 wt.%, based on the total weight of the premix.

The premix may comprise other ingredients of fabric conditioner liquids as will be known to the person skilled in the art. Among such materials there may be mentioned: co-softeners, fatty complexing agents, antifoams, insect repellents, shading or hueing dyes, 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, dyes, colorants, sunscreens, anti-corrosion agents, drape imparting agents, anti static agents, sequestrants and ironing aids. The products of the invention may contain pearlisers and/or opacifiers. A preferred sequestrant is HEDP, an abbreviation for Etidronic acid or 1-hydroxyethane 1,1-diphosphonic acid. b. Optionally storing the premix and/or transporting the premix to a different geographical location;

The second step optional involves storing the premix and/or transporting the premix to a different geographical location, for example a different factory in a different region, or even a different country.

Storing the premix allows a concentrated batch to be made and then portions of the batch diluted as and when required. Preferably if the premix is stored, storage is for 24 hours to 60 days.

Transporting the premix to other locations allows localised dilution of a fabric conditioner and therefore reduces transport costs and carbon emissions. Transport may be my any suitable means, for example road, rail, sea or air.

The premix may be stored before and/or after transportation. c. Diluting the premix in water;

The third step involves diluting the premixin a quantity of water. The premix is diluted by mixing with a quantity of water. Preferably the quantity of water is 30% to 90% by weight of the final fabric conditioner composition, preferably 40% to 80 % by weight of the final fabric conditioner composition, more preferably 45 % to 75 % by weight of the final fabric conditioner composition.

The amount of premix diluted in the water is preferably 3 wt.% to 50 wt. %, more preferably 5 to 40 wt.%, most preferably 5 wt.% to 30 wt.% by weight of the final fabric conditioner composition.

The temperature of the water is preferably 15 to 30°C.

The premix and water are preferably agitated, for example by mechanical mixing. Preferably the premix and water are mixed or agitated for at least 1 minute, preferably at least 2 minutes. Preferably the energy input for agitation is 0.1 to 0.2 W/kg (watts/kilogram), more preferably 0.14 to 0.18 W/kg. d. Separately dispersing a rheology modifier in water;

The fourth step involves dispersing a rheology modifier in water. This step may occur before, after or concurrently with step c. Preferably the quantity of water is 5% to 40% by weight of the final fabric conditioner composition, preferably 5% to 35 % by weight of the final fabric conditioner composition, more preferably 10 % to 30 % by weight of the final fabric conditioner composition.

The temperature of the water is preferably 15 to 30°C.

Generally to disperse the rheology modifier, mechanical mixing is required. Preferably the water and rheology modifier are mixed or agitated for at least 1 minute, preferably 5 minutes. Preferably the energy input for agitation is 0.22 to 0.32, preferably 0.25 to 0.3 W/kg.

In the method of the present invention a rheology modifier is employed. Rheology modifiers may be used to "thicken" or "thin" liquid compositions to a desired viscosity.

The amount of rheology modifier dispersed in the water is preferably 0.01 wt.% to 1 wt. %, more preferably 0.1 to 0.5 wt.%, most preferably 0.18 wt.% to 0.3 wt.% by weight of weight of the final fabric conditioner composition.

Suitable rheology modifiers are preferably polymeric materials. The rheology modifier may be synthetic alternatively the rheology modifier may be wholly or partly derived from natural sources such as cellulosic fibres (for example, m icrof i b ri 11 ated cellulose, which may be derived from a bacterial, fungal, or plant origin, including from wood).

Naturally derived polymeric rheology modifiers may comprise hydroxyethyl cellulose, hydrophobically modified hydroxyethyl cellulose, carboxymethyl cellulose, polysaccharide derivatives and mixtures thereof. Polysaccharide derivatives may comprise pectine, alginate, arabinogalactan (gum Arabic), carrageenan, gellan gum, xanthan gum, guar gum and mixtures thereof.

Synthetic polymeric rheology modifiers may comprise polycarboxylates, polyacrylates, hydrophobically modified ethoxylated urethanes, hydrophobically modified non-ionic polyols and mixtures thereof. Polycarboxylate polymers may comprise a polyacrylate, polymethacrylate or mixtures thereof. Polyacrylates may comprise a copolymer of unsaturated mono- or di-carbonic acid and C1-C30 alkyl ester of the (meth)acrylic acid. Such copolymers are available from Noveon Inc. under the tradename Carbopol Aqua 30. Another suitable structurant is sold under the tradename Rheovis CDE, available from BASF.

Preferably the rheology modifier is selected from polyacrylates, polysaccharides, polysaccharide derivatives, or combinations thereof. Polysaccharide derivatives typically used as rheology modifiers comprise polymeric gum materials. Such gums include pectin, alginate, arabinogalactan (gum Arabic), carrageenan, gellan gum, xanthan gum and guar gum.

The rheology modifier may preferably be a cationic polymer. Cationic polymer refers to polymers having an overall positive charge. Cationic polymers may comprise non-cationic structural units, but the rheology modifier preferably have a net cationic charge.

Preferred synthetic rheology modifiers comprise may comprise: acrylamide structural units, methacrylate structural units, acrylate structural units, methacrylic acid units and combinations thereof.

The rheology modifier may preferably be cross-linked. Preferably the rheology modifier is crosslinked with 50 to 1000 ppm of a difunctional vinyl addition monomer cross-linking agent. Particularly preferred crosslinked polymers are cross-linked copolymers of acrylamide and methacrylate cross-linked with a difunctional vinyl addition monomer, such as methylene bisacrylamide. Preferred cationic cross-linked polymers are derivable from the polymerization of from 5 to 100 mole percent of cationic vinyl addition monomer, from 0 to 95 mole percent of acrylamide and from 50 to 1000 ppm of a difunctional vinyl addition monomer cross-linking agent. Particularly preferred polymers are copolymers of 20% acrylamide and 80% MADAM methyl chloride (MADAM: dimethyl amino ethyl methacrylate) cross-linked with from 450 to 600 ppm of methylene bisacrylamide.

In one embodiment, the rheology modifier may be a cationic acrylamide copolymer which is a cationic copolymer obtained by Hofmann rearrangement in aqueous solution in the presence of an alkali and/or alkaline earth hydroxide and an alkali and/or alkaline earth hypohalide, on a base copolymer comprising:

(i) at least 5 mole % of a non-ionic monomer selected from the group consisting of acrylamide, methacrylamide, N,N-dimethylacrylamide, acrylonitrile, and combinations thereof; and

(ii) at least one comonomer selected from the group consisting of unsaturated cationic ethylenic comonomer, non-ionic comonomer, or combinations thereof, provided that the non-ionic comonomer is not acrylamide, methacrylamide, N,N- dimethylacrylamide, or acrylonitrile.

The cationic copolymer thus obtained has a desalination coefficient (Cd) of greater than 0.6 (e.g., greater than 0.65 and greater than 0.7). Cd is calculated as Real polymeric active matter (% by weight of the copolymer)* Polymer filler density Conductivity of the solution containing 9% of active matter. See also U.S. Pat. No. 8,242,215.

The unsaturated cationic ethylenic comonomer can be selected from the group consisting of dialkylaminoalkyl(meth)acrylamide monomers, diallylamine monomers, methyldiallylamine monomers, and quaternary ammonium salts or acids thereof, such as dimethyldiallylammonium chloride (DADMAC), acrylamidopropyltrimethyl-ammonium chloride (APTAC), methacrylamidopropyltrimethylammonium chloride (MAPTAC). Examples of the non-ionic comonomer are N-vinyl acetamide, N-vinyl formamide, N-vinylpyrrolidone, vinyl acetate, and combinations thereof.

The base copolymer is preferably branched in the presence of a branching agent selected from the group consisting of methylene bisacrylamide, ethylene glycol di-acrylate, polyethylene glycol dimethacrylate, diacrylamide, cyanomethylacrylate, vinyloxyethylacrylate, vinyloxyethylmethacrylate, triallylamine, formaldehyde, glyoxal, and a glycidylether type compound. More examples of the cationic acrylamide copolymers can be found in U.S. Pat. No. 8,242,215.

Examples of suitable rheology modifiers are commercially available from SNF Floerger under the trade names Flosoft FS 200, Flosoft FS 222, Flosoft FS 555, and Flosoft FS 228 and are commercially available from BASF under the trade names Rheovis CDE and Rheovis FRC. See also WO 2007141310, US 20060252668, and US 20100326614. e. Mixing the diluted premix and the dispersed rheology modifier.

The last step of the process involves mixing the diluted premix from step (c) and the dispersed rheology modifier from step (d). Once mixed, the final fabric conditioner composition is obtained. The mixing may occur by adding the diluted premix to a vessel containing the dispersed rheology modifier, adding the dispersed rheology modifier to a vessel comprising the diluted premix or concurrently adding both compositions to one vessel. Preferably mechanical mixing or agitation occurs for example stirring, preferably the compositions are mixed or agitated for at least 1 minute, more preferably 2 minutes. Preferably the energy input for agitation is 0.22 to 0.32, preferably 0.25 to 0.3 W/kg.

The viscosity of the fabric conditioner is preferably 40 to 100 mPa.s ¹, more preferably 50 to 100 mPa.s ¹. Viscosity is measured at Thermo Scientific Haake Viscotester 550 model with a

MV1 Sensor System for 15 seconds using 106 viscosity range with temperature of 25°C.

Example:

Fabric conditioners were prepared by various methods. Table 1: Premix composition

Fabric softening active ¹ - Dialkyloxyethyl Hydroxyethyl Methyl Ammonium Methyl sulphate Non-ionic surfactant ² - Alcohol ethoxylate having C16: 18 chain and 25 EO groups The rheology modifier used in all examples was a cationic acrylamide.

The premix was prepared by heating water to 50°C, adding the encapsulated perfume, non ionic surfactant and minors with agitation. Separately pre-melting the fabric softening active at a temperature of ~65°C. Adding the fabric softening active to the water and other ingredients with stirring. The mixture was then cooled and the free perfume added.

Example process A:

Rheology modifier was added directly to the premix and mixed.

Water equating to 80% of the final fabric conditioner composition was then added with siring. Example process B:

Rheology modifier was added directly to water equating to 80% of the final fabric conditioner composition.

The premix was then added to the composition with stirring. Example process C:

The premix and rheology modifier were added simultaneously, directly to water equating to 80% of the final fabric conditioner composition and the mixture stirred.

Example process 1:

The rheology modifier was mixed with room temperature water: 0.24 wt.% by weight of the final fabric conditioner formulation of rheology modifier and 25 wt.% by weight of the final fabric conditioner formulation of water. The mixture was stirred for 12 minutes, until the polymer was dispersed.

The premix was then mixed with room temperature water: 14 wt.% by weight of the final fabric conditioner formulation of premix and 60 wt.% by weight of the final fabric conditioner formulation of water. The mixture was stirred for 5 minutes

The dispersed rheology modifier was then mixed with the diluted premix stirred for a further 5 minutes. The final fabric conditioner composition was obtained, having a consumer acceptable viscosity. Table 2: results

As demonstrated, only by following the process described herein is a stable fabric conditioner, having a consumer acceptable viscosity obtained.

Claims

1) A method for the production of a fabric conditioner, wherein the method comprises the steps of: a. Production of a premix comprising fabric softening active and perfume; b. Optionally storing the premix and/or transporting the premix to a different geographical location; c. Diluting the premix in water; d. Separately dispersing a rheology modifier in water; e. Mixing the diluted premix from step (c) and dispersed rheology modifier from step (d) to produce the final fabric conditioner composition.

2) A method according to claim 1 , wherein the fabric softening active comprises quaternary ammonium compounds.

3) A method according to any proceeding claim, wherein the premix is produced by forming a pre-melt of fabric softening active and mixing the pre-melt with the remaining ingredients in the premix.

4) A method according to any preceding claim, wherein, the amount of premix diluted in the water in step (c) is 3 wt.% to 50 wt. % premix, by weight of the final fabric conditioner composition.

5) A method according to any preceding claim, wherein the premix is diluted with a quantity of water, the quantity of water being 30% to 90% by weight of the final fabric conditioner composition.

6) A method according to any preceding claim, wherein the amount of rheology modifier dispersed in water in step (d) is 0.01 wt.% to 1 wt. % rheology modifier by weight of the final fabric conditioner composition.

7) A method according to any preceding claim, wherein the rheology modifier is dispersed in a quantity of water, the quantity of water being 5% to 40% by weight of the final fabric conditioner composition.

8) A method according to any preceding claim, wherein the rheology modifier is polymeric. 9) A method according to any preceding claim, wherein the rheology modifier comprises hydroxyethyl cellulose, hydrophobically modified hydroxyethyl cellulose, carboxymethyl cellulose, polysaccharide derivatives, polycarboxylates, polyacrylates, hydrophobically modified ethoxylated urethanes, hydrophobically modified non-ionic polyols and mixtures thereof.

10) A method according to any preceding claim wherein the rheology modifier is cross linked. 11) A method according to any preceding claim wherein the rheology modifier is cationic.