WO2020016195A1

WO2020016195A1 - Benefit agent delivery particles

Info

Publication number: WO2020016195A1
Application number: PCT/EP2019/069045
Authority: WO
Inventors: Craig Warren Jones; Maria Fernanda Jimenez Solomon
Original assignee: Unilever Plc; Unilever N.V.; Conopco, Inc., D/B/A Unilever
Priority date: 2018-07-17
Filing date: 2019-07-15
Publication date: 2020-01-23
Also published as: EP3850074B1; CN112639067A; EP3850074A1; BR112021000726A2; BR112021000726B1; ZA202100029B; EP3850074B8

Abstract

The invention provides a benefit agent delivery particle having a core-shell structure in which a porous shell of polymeric material entraps a core containing the benefit agent; in which the pores in the shell are at least partially occluded by a wash-removable coating provided at the exterior surface of the shell; and characterized in that the wash-removable coating is formed from deposited melamine/acid complex.

Description

BENEFIT AGENT DELIVERY PARTICLES

Field of the Invention

The present invention relates to benefit agent (such as fragrance) delivery particles and compositions (such as laundry treatment compositions) comprising them.

Background and Prior Art

In laundry treatment compositions such as laundry detergents, the fragrance experienced by consumers is one of the most important attributes. Efficient delivery of the right fragrances to the fabric during the laundry process and release of that fragrance at key consumer moments is critical to the delivery of clean and fresh laundry.

The delivery of fragrance at key moments is a difficult task since laundry detergents are usually designed to carry oily materials or particulate solids away from the laundered fabric. Fragrances, however, are also typically oily materials.

Encapsulation of fragrance allows for improved deposition of fragrance to fabric, as well as delaying the release of fragrance when the consumer garment is being worn.

However, another important moment to the consumer is when the laundry is in the “damp” phase, which extends from when the garments are being removed from the washing machine, to when they are almost dry. There is a need for a composition that delivers a good fragrance experience during this phase without significant compromise of fragrance performance at other stages such as in the packaged composition before use and when the laundered garments are dry.

The present invention addresses this problem.

Summary of the Invention

The invention also provides a laundry treatment composition comprising a benefit agent delivery particle as defined above.

Detailed Description and Preferred Embodiments

The core of the benefit agent delivery particle of the invention is typically formed in an inner region of the particle and provides a sink for the benefit agent. The shell generally protects the benefit agent from the external environment and regulates the flow of benefit agent into and out of the core.

In the benefit agent delivery particle of the invention, the presence of the wash-removable coating serves to reduce the leakage of the entrapped benefit agent through the pores in the shell. Removal of the coating during a washing operation facilitates release of the entrapped benefit agent.

The term“washing operation” as used herein generally denotes a method of laundering fabric using a laundry treatment composition according to the invention.

The wash-removable coating is formed from deposited melamine/acid complex.

Melamine/acid complexes which may be used to form the wash-removable coating preferably have a solubility in distilled water (at 25°C and at atmospheric pressure) of less than about 10mg/L, preferably less than about 1 mg/L, to prevent the coating being removed too quickly in the wash.

Suitable melamine/acid complexes which may be used to form the wash-removable coating may be derived from the association of melamine with multifunctional organic acids. Melamine is a heterocyclic aromatic molecule and consists of a triazine ring with three amine groups at the 2, 4 and 6 positions. The solubility of melamine in distilled water (at 25°C and at atmospheric pressure) is about 0.3g/L.

Preferred multifunctional organic acids for use in the invention have a solubility in distilled water (at 25°C and at atmospheric pressure) of at least about 0.1 mg/L, more preferably at least about 1 mg/L of water; and are capable of interacting with melamine to form self- assembling complexes via organized intramolecular networks. Complex formation may be driven by various noncovalent interactions including ionic interactions, tt-p stacking and complementary hydrogen bonding. Examples of preferred multifunctional organic acids for use in the invention include polycarboxylic acids such as BTCA (1 ,2,3,4—

butanetetracarboxylic acid) and especially folic acid (N-[4-(2-Amino-3,4-dihydro-4-oxo-6- pteridinylmethylamino)-benzoyl]-L-glutamic acid).

Mixtures of any of the above described materials may also be suitable.

Most preferably the melamine/acid complex used to form the wash-removable coating corresponds to the following general formula (I):

In a suitable process used to prepare a benefit agent delivery particle of the invention, the melamine, followed by the multifunctional organic acid, are mixed into a slurry of pre formed particles having a core-shell structure in which a porous shell of polymeric material surrounds a core containing the benefit agent (hereinafter termed“pre-formed core-shell particles”).

Preferably the melamine and the multifunctional organic acid are mixed in a molar ratio of from about 2:1 to about 10:1.

Preferably the slurry of pre-formed core-shell particles is a dilute aqueous slurry with a water content of at least 60%, preferably at least 80% (by weight based on total weight). Dilution may help to facilitate solubilization of the multifunctional organic acid and/or prevent agglomeration.

Preferably the slurry is heated to at least 50°C, more preferably at least 60°C, to enable complexation of the melamine and the multifunctional organic acid. On cooling, the melamine/acid complex deposits by precipitation onto the exterior shell surface of the pre- formed core-shell particles. The coating is formed from the deposited melamine/acid complex, which typically forms lamellar structures such as flakes, platelets or leaves on the exterior shell surface. Secondary structures (such as membranes, spherulites and networks) may also be formed.

Successful coating of the core-shell particles may suitably be corroborated with high resolution SEM imaging.

Preferred pre-formed core-shell particles have a negative charge at their exterior shell surface and have a zeta potential of from -0.1 meV to -100meV, more preferably from - 10meV to -80 meV, and most preferably from - 20meV to -75meV. The zeta potential is suitably measured by a dynamic light scattering (DLS) method using a Zetasizer Nano™ ZS90 (Malvern Instruments Ltd, UK) at 25° C. A dispersion of the particles in deionised water with a solids content of around 500 ppm and a pH adjusted to about 7 is used for the measurement.

Pre-formed core-shell particles may suitably be made using methods known to those skilled in the art such as coacervation, interfacial polymerization, and polycondensation. The process of coacervation typically involves encapsulation of a generally water- insoluble core material by the precipitation of colloidal material(s) onto the surface of droplets of the material. Coacervation may be simple e.g. using one colloid such as gelatin, or complex where two or possibly more colloids of opposite charge, such as gelatin and gum arabic or gelatin and carboxymethyl cellulose, are used under carefully controlled conditions of pH, temperature and concentration.

Interfacial polymerisation typically proceeds with the formation of a fine dispersion of oil droplets (the oil droplets containing the core material) in an aqueous continuous phase. The dispersed droplets form the core of the future core-shell particle and the dimensions of the dispersed droplets directly determine the size of the future core-shell particle. Shell- forming materials (monomers or oligomers) are contained in both the dispersed phase (oil droplets) and the aqueous continuous phase and they react together at the phase interface to build a polymeric wall around the oil droplets thereby to encapsulate the droplets. An example of a core-shell particle produced by this method has a polyurea shell formed by reaction of diisocyanates or polyisocyanates with diamines or

polyamines.

Polycondensation involves forming a dispersion or emulsion of the core material in an aqueous solution of precondensate of polymeric materials under appropriate conditions of agitation to produce dispersed core material of a desired particle size, and adjusting the reaction conditions to cause condensation of the precondensate by acid catalysis, resulting in the condensate separating from solution and surrounding the dispersed core material to produce a coherent film and the desired particles. An example of a core-shell particle produced by this method has an aminoplast shell formed from the

polycondensation product of melamine (2,4,6-triamino-1 ,3,5-triazine) or urea with formaldehyde. Suitable cross-linking agents (e.g. toluene diisocyanate, divinyl benzene, butanediol diacrylate) may also be used and secondary wall polymers may also be used as appropriate, e.g. anhydrides and their derivatives, particularly polymers and co- polymers of maleic anhydride.

In the benefit agent delivery particle of the invention, the porous shell of polymeric material is preferably an aminoplast shell formed from the polycondensation product of melamine with formaldehyde. The shell is preferably of a generally spherical shape; and will typically comprise at most 20% by weight based on the total weight of the benefit agent delivery particle.

The benefit agent delivery particle of the invention will generally have an average particle size between 100 nanometers and 50 microns. Particles larger than this are entering the visible range. Examples of particles in the sub-micron range include latexes and mini- emulsions with an average particle size ranging from 100 to 600 nanometers. Core-shell particles suitable for use in the invention preferably have an average size of from 0.6 to 50 microns, more preferably from 2 to 30 microns and most preferably from 5 to 25 microns. The particle size distribution can be narrow, broad or multimodal. If necessary, the particles as initially produced may be filtered or screened to produce a product of greater size uniformity.

"Size" as used herein refers to diameter unless otherwise stated. For samples

with particle diameter no greater than 1 micron, diameter means the z-average particle size measured, for example, using dynamic light scattering (as set out in international standard ISO 13321 ) with an instrument such as a Zetasizer Nano™

ZS90 (Malvern Instruments Ltd, UK). For samples with particle diameter greater than 1 micron, diameter means the apparent volume median diameter (D50), measurable for example, by laser diffraction (as set out in international standard ISO 13320) with an instrument such as a Mastersizer™ 2000 (Malvern Instruments Ltd, UK).

The benefit agent delivery particle of the invention may be provided with a deposition aid at the exterior shell surface. Deposition aids serve to modify the properties of the exterior shell surface, for example to make the particle more substantive to a desired substrate. Desired substrates include cellulosics (including cotton) and polyesters (including those employed in the manufacture of polyester fabrics).

The deposition aid may suitably be provided at the exterior shell surface by means of covalent bonding, entanglement or strong adsorption. Preferably such a deposition aid is attached to the exterior shell surface by means of covalent bonding, either directly or via a linking species. Deposition aids for use in the invention may suitably be selected from polysaccharides having an affinity for cellulose. Such polysaccharides may be naturally occurring or synthetic and may have an intrinsic affinity for cellulose or may have been derivatised or otherwise modified to have an affinity for cellulose. Suitable polysaccharides have a 1-4 linked b glycan (generalised sugar) backbone structure with at least 4, and preferably at least 10 backbone residues which are b1-4 linked, such as a glucan backbone (consisting of b1-4 linked glucose residues), a mannan backbone (consisting of b1 -4 linked mannose residues) or a xylan backbone (consisting of b1 -4 linked xylose residues). Examples of such b1 -4 linked polysaccharides include xyloglucans, glucomannans, mannans, galactomannans, b(1-3),(1-4) glucan and the xylan family incorporating glucurono-, arabino- and glucuronoarabinoxylans. Preferred b1 -4 linked polysaccharides for use in the invention may be selected from xyloglucans of plant origin, such as pea xyloglucan and tamarind seed xyloglucan (TXG) (which has a b1 -4 linked glucan backbone with side chains of a-D xylopyranose and b-D-galactopyranosyl-(1-2)-a-D-xylo-pyranose, both 1-6 linked to the backbone); and galactomannans of plant origin such as locust bean gum (LBG) (which has a mannan backbone of b1 -4 linked mannose residues, with single unit galactose side chains linked a1-6 to the backbone).

Also suitable are polysaccharides which may gain an affinity for cellulose upon hydrolysis, such as cellulose mono-acetate; or modified polysaccharides with an affinity for cellulose such as hydroxypropyl cellulose, hydroxypropyl methylcellulose, hydroxyethyl

methylcellulose, hydroxypropyl guar, hydroxyethyl ethylcellulose and methylcellulose.

Deposition aids for use in the invention may also be selected from phthalate containing polymers having an affinity for polyester. Such phthalate containing polymers may have one or more nonionic hydrophilic segments comprising oxyalkylene groups (such as oxyethylene, polyoxyethylene, oxypropylene or polyoxypropylene groups), and one or more hydrophobic segments comprising terephthalate groups. Typically, the oxyalkylene groups will have a degree of polymerization of from 1 to about 400, preferably from 100 to about 350, more preferably from 200 to about 300. A suitable example of a phthalate containing polymer of this type is a copolymer having random blocks of ethylene terephthalate and polyethylene oxide terephthalate. Mixtures of any of the above described materials may also be suitable.

Deposition aids for use in the invention will generally have a weight average molecular weight (M_w) in the range of from about 5 kDa to about 500 kDa, preferably from

about 10 kDa to about 500 kDa and more preferably from about 20 kDa to about 300 kDa.

In the benefit agent delivery particle of the invention, the core contains a benefit agent. Preferred benefit agents in the context of fabric laundering include fragrance formulations, clays, enzymes, antifoams, fluorescers, bleaching agents and precursors thereof

(including photo-bleach), dyes and/or pigments, conditioning agents (for example cationic surfactants including water-insoluble quaternary ammonium materials, fatty alcohols and/or silicones), lubricants (e.g. sugar polyesters), colour and photo-protective agents (including sunscreens), antioxidants, ceramides, reducing agents, sequestrants, colour care additives (including dye fixing agents), unsaturated oil, emollients, moisturizers, insect repellents and/or pheromones, drape modifiers (e.g. polymer latex particles such as PVAc) and antimicrobial or microbe control agents.

Mixtures of any of the above described materials may also be suitable. The most preferred benefit agents in the context of this invention are fragrance formulations.

Fragrance formulations for use in the invention will typically contain a blend of selected fragrant components, optionally mixed with one or more excipients. The combined odours of the various fragrant components produce a pleasant or desired fragrance.

The term“fragrant component” in the context of this invention denotes a material which is used essentially for its ability to impart a pleasant odour to a composition (into which it is incorporated), and/or a surface (to which it is applied), either on its own or in admixture with other such materials. Materials having these characteristics are generally small, lipophilic molecules of sufficient volatility to be transported to the olfactory system in the upper part of the nose.

Fragrant components for use in the invention will typically have molecular weights of less than 325 atomic mass units, preferably less than 300 atomic mass units and more preferably less than 275 atomic mass units. The molecular weight is preferably greater than 100 atomic mass units and more preferably greater than 125 atomic mass units, since lower masses may be too volatile and/or insufficiently lipophilic to be effective.

Fragrant components for use in the invention will preferably have a molecular structure which does not contain halogen atoms and/or strongly ionizing functional groups such as sulfonates, sulfates, or quaternary ammonium ions.

Fragrant components for use in the invention will more preferably have a molecular structure containing only atoms from among, but not necessarily all, of the following: hydrogen, carbon, oxygen, nitrogen and sulphur. Most preferably the fragrant components will have a molecular structure containing only atoms from among, but not necessarily all, of the following: hydrogen, carbon and oxygen.

Examples of fragrant components include aromatic, aliphatic and araliphatic

hydrocarbons having molecular weights from about 90 to about 250; aromatic, aliphatic and araliphatic esters having molecular weights from about 130 to about 250; aromatic, aliphatic and araliphatic nitriles having molecular weights from about 90 to about 250; aromatic, aliphatic and araliphatic alcohols having molecular weights from about 90 to about 240; aromatic, aliphatic and araliphatic ketones having molecular weights from about 150 to about 270; aromatic, aliphatic and araliphatic lactones having molecular weights from about 130 to about 290; aromatic, aliphatic and araliphatic aldehydes having molecular weights from about 90 to about 230; aromatic, aliphatic and araliphatic ethers having molecular weights from about 150 to about 270; and condensation products of aldehydes and amines having molecular weights from about 180 to about 320.

Specific examples of fragrant components for use in the invention include: i) hydrocarbons, such as, for example, D-limonene, 3-carene, a-pinene, b-pinene, a- terpinene, g-terpinene, p-cymene, bisabolene, camphene, caryophyllene, cedrene, - farnesene, longifolene, myrcene, ocimene, valencene, (E,Z)-1 ,3,5-undecatriene, styrene, and diphenylmethane; ii) aliphatic and araliphatic alcohols, such as, for example, benzyl alcohol, 1 -phenylethyl alcohol, 2-phenylethyl alcohol, 3-phenylpropanol, 2-phenylpropanol, 2-phenoxyethanol, 2,2-dimethyl-3-phenylpropanol, 2,2-dimethyl-3-(3-methylphenyl)propanol, 1 , 1 -dimethyl-2- phenylethyl alcohol, 1 ,1 -dimethyl-3-phenylpropanol, 1 -ethyl-1 -methyl-3-phenylpropanol, 2-methyl-5-phenylpentanol, 3-methyl-5-phenylpentanol, 3-phenyl-2-propen-1-ol, 4- methoxybenzyl alcohol, 1 -(4-isopropylphenyl)ethanol, hexanol, octanol, 3-octanol, 2,6- dimethylheptanol, 2-methyl-2-heptanol, 2-methyl-2-octanol, (E)-2-hexenol, (E)- and (Z)-3- hexenol, 1 -octen-3-ol, a mixture of 3,4,5,6,6-pentamethyl-3/4-hepten-2-ol and 3, 5,6,6- tetramethyl-4-methyleneheptan-2-ol, (E,Z)-2,6-nonadienol, 3,7-dimethyl-7-methoxyoctan-

2-ol, 9-decenol, 10-undecenol, and 4-methyl-3-decen-5-ol; iii) cyclic and cycloaliphatic alcohols, such as, for example, 4-tert-butylcyclohexanol, 3,3,5-trimethylcyclohexanol, 3-isocamphylcyclohexanol, 2,6,9-trimethyl-Z2,Z5,E9- cyclododecatrien-1-ol, 2-isobutyl-4-methyltetrahydro-2H-pyran-4-ol, alpha, 3,3- trimethylcyclo-hexylmethanol, 2-methyl-4-(2,2,3-trimethyl-3-cyclopent-1 -yl)butanol, 2- methyl-4-(2,2,3-trimethyl-3-cyclopent-1-yl)-2-buten-1 -ol, 2-ethyl-4-(2,2,3-trimethyl-3- cyclopent-1 -yl)-2-buten-1-ol, 3-methyl-5-(2,2,3-trimethyl-3-cyclopent-1-yl)-pentan-2-ol, 3- methyl-5-(2,2,3-trimethyl-3-cyclopent-1-yl)-4-penten-2-ol, 3,3-dimethyl-5-(2,2,3-trimethyl-

3-cyclopent-1 -yl)-4-penten-2-ol, 1 -(2,2,6-trimethylcyclohexyl)pentan-3-ol, and 1 -(2,2,6- trimethylcyclohexyl)hexan-3-ol; iv) aliphatic aldehydes and their acetals, such as, for example, hexanal, heptanal, octanal, nonanal, decanal, undecanal, dodecanal, tridecanal, 2-methyloctanal, 2- methylnonanal, 2-methylundecanal, (E)-2-hexenal, (Z)-4-heptenal, 2,6-dimethyl-5- heptenal, 10-undecenal, (E)-4-decenal, 2-dodecenal, 2,6,10-trimethyl-5,9-undecadienal, heptanal-diethylacetal, 1 ,1 -dimethoxy-2,2,5-trimethyl-4-hexene, and citronellyl oxyacetaldehyde; v) aliphatic ketones and oximes thereof, such as, for example, 2-heptanone, 2-octanone, 3-octanone, 2-nonanone, 5-methyl-3-heptanone, 5-methyl-3-heptanone oxime, and 2,4,4,7-tetramethyl-6-octen-3-one; vi) aliphatic sulfur-containing compounds, such as, for example, 3-methylthiohexanol, 3- methylthiohexyl acetate, 3-mercaptohexanol, 3-mercaptohexyl acetate, 3-mercaptohexyl butyrate, 3-acetylthiohexyl acetate, and 1-menthene-8-thiol; vii) aliphatic nitriles, such as, for example, 2-nonenenitrile, 2-tridecenenitrile, 2,12- tridecenenitrile, 3,7-dimethyl-2,6-octadienenitrile, and 3,7-dimethyl-6-octenenitrile; viii) aliphatic carboxylic acids and esters thereof, such as, for example, (E)- and (Z)-3- hexenylformate, ethyl acetoacetate, isoamyl acetate, hexyl acetate, 3,5,5-trimethylhexyl acetate, 3-methyl-2-butenyl acetate, (E)-2-hexenyl acetate, (E)- and (Z)-3-hexenyl acetate, octyl acetate, 3-octyl acetate, 1-octen-3-yl acetate, ethyl butyrate, butyl butyrate, isoamyl butyrate, hexylbutyrate, (E)- and (Z)-3-hexenyl isobutyrate, hexyl crotonate, ethylisovalerate, ethyl-2-methyl pentanoate, ethyl hexanoate, allyl hexanoate, ethyl heptanoate, allyl heptanoate, ethyl octanoate, ethyl-(E,Z)-2,4-decadienoate, methyl-2- octinate, methyl-2-noninate, allyl-2-isoamyl oxyacetate, and methyl-3, 7-dimethyl-2, 6- octadienoate; ix) acyclic terpene alcohols, such as, for example, citronellol; geraniol; nerol; linalool; lavandulol; nerolidol; farnesol; tetrahydrolinalool; tetrahydrogeraniol; 2,6-dimethyl-7- octen-2-ol; 2,6-dimethyloctan-2-ol; 2-methyl-6-methylene-7-octen-2-ol; 2,6-dimethyl-5,7- octadien-2-ol; 2,6-dimethyl-3,5-octadien-2-ol; 3,7-dimethyl-4,6-octadien-3-ol; 3,7- dimethyl-1 ,5,7-octatrien-3-ol 2,6-dimethyl-2,5,7-octatrien-1-ol; as well as formates, acetates, propionates, isobutyrates, butyrates, isovalerates, pentanoates, hexanoates, crotonates, tiglinates and 3-methyl-2-butenoates thereof; x) acyclic terpene aldehydes and ketones, such as, for example, geranial, neral, citronellal, 7-hydroxy-3,7-dimethyloctanal, 7-methoxy-3,7-dimethyloctanal, 2,6,10- trimethyl-9-undecenal, osinensal, b-sinensal, geranylacetone, as well as the dimethyl- and diethylacetals of geranial, neral and 7-hydroxy-3,7-dimethyloctanal; xi) cyclic terpene alcohols, such as, for example, menthol, isopulegol, alpha-terpineol, terpinen-4-ol, menthan-8-ol, menthan-1-ol, menthan-7-ol, borneol, isoborneol, linalool oxide, nopol, cedrol, ambrinol, vetiverol, guaiol, and the formates, acetates, propionates, isobutyrates, butyrates, isovalerates, pentanoates, hexanoates, crotonates, tiglinates and 3-methyl-2-butenoates of alpha-terpineol, terpinen-4-ol, methan-8-ol, methan-1-ol, methan-7-ol, borneol, isoborneol, linalool oxide, nopol, cedrol, ambrinol, vetiverol, and guaiol; xii) cyclic terpene aldehydes and ketones, such as, for example, menthone, isomenthone, 8-mercaptomenthan-3-one, carvone, camphor, fenchone, a-ionone, b-ionone, a-n- methylionone, b-n-methylionone, a-isomethylionone, b-isomethylionone, alpha-irone, o damascone, b-damascone, b-damascenone, d-damascone, g-damascone, 1 -(2,4,4- trimethyl-2-cyclohexen-1-yl)-2-buten-1-one, 1 ,3,4,6,7,8a-hexahydro-1 ,1 ,5,5-tetramethyl- 2H-2,4a-methanonaphthalen-8(5H)-one, nootkatone, dihydronootkatone and cedryl methyl ketone; xiii) cyclic and cycloaliphatic ethers, such as, for example, cineole, cedryl methyl ether, cyclododecyl methyl ether, (ethoxymethoxy)cyclododecane; alpha-cedrene epoxide, 3a,6,6,9a-tetramethyldodecahydronaphtho[2,1-b]furan, 3a-ethyl-6,6,9a- trimethyldodecahydronaphtho[2,1-b]furan, 1 ,5,9-trimethyl-13-oxabicyclo[10.1.0]-trideca- 4, 8-diene, rose oxide and 2-(2,4-dimethyl-3-cyclohexen-1-yl)-5-methyl-5-(1-methylpropyl)- 1 ,3-dioxane; xiv) cyclic ketones, such as, for example, 4-tert-butylcyclohexanone, 2,2,5-trimethyl-5- pentylcyclopentanone, 2-heptylcyclopentanone, 2-pentylcyclopentanone, 2-hydroxy-3- methyl-2-cyclopenten-1-one, 3-methyl-cis-2-penten-1-yl-2-cyclopenten-1-one, 3-methyl-2- pentyl-2-cyclopenten-1-one, 3-methyl-4-cyclopentadecenone, 3-methyl-5- cyclopentadecenone, 3-methylcyclopentadecanone, 4-(1 -ethoxyvinyl)-3, 3,5,5- tetramethylcyclohexanone, 4-tert-pentylcyclohexanone, 5-cyclohexadecen-1-one, 6,7- dihydro-1 ,1 ,2,3,3-pentamethyl-4(5H)-indanone, 5-cyclohexadecen-1-one, 8- cyclohexadecen-1-one, 9-cycloheptadecen-1-one and cyclopentadecanone; xv) cycloaliphatic aldehydes and ketones, such as, for example, 2,4-dimethyl-3- cyclohexene carbaldehyde, 2-methyl-4-(2,2,6-trimethyl-cyclohexen-1-yl)-2-butenal, 4-(4- hydroxy-4-methylpentyl)-3-cyclohexene carbaldehyde, 4-(4-methyl-3-penten-1 -yl)-3- cyclohexene carbaldehyde, 1-(3,3-dimethylcyclohexyl)-4-penten-1-one, 1-(5,5-dimethyl-1- cyclohexen-1-yl)-4-penten-1-one, 2,3,8,8-tetramethyl-1 ,2,3,4,5,6,7,8-octahydro-2- naphtalenyl methyl-ketone, methyl-2,6,10-tri methyl-2, 5, 9-cyclododecatrienyl ketone and tert-butyl-(2,4-dimethyl-3-cyclohexen-1 -yl) ketone; xvi) esters of cyclic alcohols, such as, for example, 2-tert-butylcyclohexyl acetate, 4-tert- butylcyclohexyl acetate, 2-tert-pentylcyclohexyl acetate, 4-tert-pentylcyclohexyl acetate, decahydro-2-naphthyl acetate, 3-pentyltetrahydro-2H-pyran-4-yl acetate, decahydro- 2,5,5,8a-tetramethyl-2-naphthyl acetate, 4,7-methano-3a,4,5,6,7,7a-hexahydro-5 or 6- indenyl acetate, 4,7-methano-3a,4,5,6,7,7a-hexahydro-5 or 6-indenyl propionate, 4,7- methano-3a,4,5,6,7,7a-hexahydro-5 or 6-indenyl-isobutyrate and 4,7-methanooctahydro- 5 or 6-indenyl acetate; xvii) esters of cycloaliphatic carboxylic acids, such as, for example, allyl 3-cyclohexyl- propionate, allyl cyclohexyl oxyacetate, methyl dihydrojasmonate, methyl jasmonate, methyl 2-hexyl-3-oxocyclopentanecarboxylate, ethyl 2-ethyl-6,6-dimethyl-2- cyclohexenecarboxylate, ethyl 2,3,6,6-tetramethyl-2-cyclohexenecarboxylate and ethyl 2- methyl-1 ,3-dioxolane-2-acetate; xviii) esters of araliphatic alcohols and aliphatic carboxylic acids, such as, for example, benzyl acetate, benzyl propionate, benzyl isobutyrate, benzyl isovalerate, 2-phenylethyl acetate, 2-phenylethyl propionate, 2-phenylethyl isobutyrate, 2-phenylethyl isovalerate, 1- phenylethyl acetate, a-trichloromethylbenzyl acetate, a,a-dimethylphenylethyl acetate, a,a-dimethylphenylethyl butyrate, cinnamyl acetate, 2-phenoxyethyl isobutyrate and 4- methoxybenzyl acetate; xix) araliphatic ethers and their acetals, such as, for example, 2-phenylethyl methyl ether, 2-phenylethyl isoamyl ether, 2-phenyethyl cyclohexyl ether, 2-phenylethyl-1-ethoxyethyl ether, phenylacetaldehyde dimethyl acetal, phenylacetaldehyde diethyl acetal, 2- phenylpropionaldehyde dimethyl acetal, phenylacetaldehyde glycerol acetal, 2,4,6- trimethyl-4-phenyl-1 ,3-dioxane, 4,4a,5,9b-tetrahydroindeno[1 ,2-d]-m-dioxin and

4,4a,5,9b-tetrahydro-2,4-dimethylindeno[1 ,2-d]-m-dioxin; xx) aromatic and araliphatic aldehydes and ketones, such as, for example, benzaldehyde; phenylacetaldehyde, 3-phenylpropanal, 2-phenyl propanal, 4-methylbenzaldehyde, 4- methylphenylacetaldehyde, 3-(4-ethylphenyl)-2,2-dimethylpropanal, 2-methyl-3-(4- isopropylphenyl)propanal, 2-methyl-3-(4-tert-butylphenyl)propanal, 3-(4-tert- butylphenyl)propanal, cinnamaldehyde, alpha-butylcinnamaldehyde, alpha- amylcinnamaldehyde, alpha-hexylcinnamaldehyde, 3-methyl-5-phenylpentanal, 4- methoxybenzaldehyde, 4-hydroxy-3-methoxybenzaldehyde, 4-hydroxy-3- ethoxybenzaldehyde, 3,4-methylene-dioxybenzaldehyde, 3,4-dimethoxybenzaldehyde, 2- methyl-3-(4-methoxyphenyl)propanal, 2-methyl-3-(4-methylendioxyphenyl)propanal, acetophenone, 4-methylacetophenone, 4-methoxyacetophenone, 4-tert-butyl- 2,6-dimethylacetophenone, 4-phenyl-2-butanone, 4-(4-hydroxyphenyl)-2-butanone, 1-(2- naphthalenyl)ethanone, benzophenone, 1 ,1 ,2,3,3,6-hexamethyl-5-indanyl methyl ketone, 6-tert-butyl-1 , 1 -dimethyl-4-indanyl methyl ketone, 1-[2,3-dihydro-1 ,1 ,2,6-tetramethyl-3-(1- methyl-ethyl)-1 H-5-indenyl]ethanone and 5',6',7',8'-tetrahydro-3',5',5',6',8',8'-hexamethyl- 2-acetonaphthone; xxi) aromatic and araliphatic carboxylic acids and esters thereof, such as, for example, benzoic acid, phenylacetic acid, methyl benzoate, ethyl benzoate, hexyl benzoate, benzyl benzoate, methyl phenylacetate, ethyl phenylacetate, geranyl phenylacetate, phenylethyl phenylacetate, methyl cinnamate, ethyl cinnamate, benzyl cinnamate, phenylethyl cinnamate, cinnamyl cinnamate, allyl phenoxyacetate, methyl salicylate, isoamyl salicylate, hexyl salicylate, cyclohexyl salicylate, cis-3-hexenyl salicylate, benzyl salicylate, phenylethyl salicylate, methyl 2,4-dihydroxy-3,6-dimethylbenzoate, ethyl 3- phenylglycidate and ethyl 3-methyl-3-phenylglycidate; xxii) nitrogen-containing aromatic compounds, such as, for example, 2,4,6-trinitro-1 ,3- dimethyl-5-tert-butylbenzene, 3,5-dinitro-2,6-dimethyl-4-tert-butylacetophenone, cinnamonitrile, 5-phenyl-3-methyl-2-pentenonitrile, 5-phenyl-3-methylpentanonitrile, methyl anthranilate, methyl-N-methylanthranilate, Schiff's bases of methyl anthranilate with 7-hydroxy-3,7-dimethyloctanal, 2-methyl-3-(4-tert.-butylphenyl)propanal or 2,4- dimethyl-3-cyclohexene carbaldehyde, 6-isopropylquinoline, 6-isobutylquinoline, 6-sec- butylquinoline, indole, skatole, 2-methoxy-3-isopropylpyrazine and 2-isobutyl-3- methoxypyrazine; xxiii) phenols, phenyl ethers and phenyl esters, such as, for example, estragole, anethole, eugenol, eugenyl methyl ether, isoeugenol, isoeugenol methyl ether, thymol, carvacrol, diphenyl ether, beta-naphthyl methyl ether, beta-naphthyl ethyl ether, beta-naphthyl isobutyl ether, 1 ,4-dimethoxybenzene, eugenyl acetate, 2-methoxy-4-methylphenol, 2- ethoxy-5-(1-propenyl)phenol and p-cresyl phenylacetate; xxiv) heterocyclic compounds, such as, for example, 2,5-dimethyl-4-hydroxy-2H-furan-3- one, 2-ethyl-4-hydroxy-5-methyl-2H-furan-3-one, 3-hydroxy-2-methyl-4H-pyran-4-one, 2- ethyl-3-hydroxy-4H-pyran-4-one; xxv) lactones, such as, for example, 1 ,4-octanolide, 3-methyl-1 ,4-octanolide, 1 ,4- nonanolide, 1 ,4-decanolide, 8-decen-1 ,4-olide, 1 ,4-undecanolide, 1 ,4-dodecanolide, 1 ,5- decanolide, 1 ,5-dodecanolide, 1 ,15-pentadecanolide, cis- and trans-1 '-pentadecen-1 ,15- olide, cis- and trans-12-pentadecen-1 ,15-olide, 1 ,16-hexadecanolide, 9-hexadecen-1 ,16- olide, 10-oxa-1 ,16-hexadecanolide, 11-oxa-1 ,16-hexadecanolide, 12-oxa-1 ,16- hexadecanolide, ethylene-1 , 12-dodecanedioate, ethylene-1 ,13-tridecanedioate, coumarin, 2,3-dihydrocoumarin, and octahydrocoumarin.

Naturally occurring exudates such as essential oils extracted from plants may also be used as fragrant components in the invention. Essential oils are usually extracted by processes of steam distillation, solid-phase extraction, cold pressing, solvent extraction, supercritical fluid extraction, hydrodistillation or simultaneous distillation-extraction.

Essential oils may be derived from several different parts of the plant, including for example leaves, flowers, roots, buds, twigs, rhizomes, heartwood, bark, resin, seeds and fruits. The major plant families from which essential oils are extracted include Asteraceae, Myrtaceae, Lauraceae, Lamiaceae, Myrtaceae, Rutaceae and Zingiberaceae. The oil is "essential" in the sense that it carries a distinctive scent, or essence, of the plant.

Essential oils are understood by those skilled in the art to be complex mixtures which generally consist of several tens or hundreds of constituents. Most of these constituents possess an isoprenoid skeleton with 10 atoms of carbon (monoterpenes), 15 atoms of carbon (sesquiterpenes) or 20 atoms of carbon (diterpenes). Lesser quantities of other constituents can also be found, such as alcohols, aldehydes, esters and phenols.

However, an individual essential oil is usually considered as a single ingredient in the context of practical fragrance formulation. Therefore, an individual essential oil may be considered as a single fragrant component for the purposes of this invention. Specific examples of essential oils for use as fragrant components in the invention include cedarwood oil, juniper oil, cumin oil, cinnamon bark oil, camphor oil, rosewood oil, ginger oil, basil oil, eucalyptus oil, lemongrass oil, peppermint oil, rosemary oil, spearmint oil, tea tree oil, frankincense oil, chamomile oil, clove oil, jasmine oil, lavender oil, rose oil, ylang-ylang oil, bergamot oil, grapefruit oil, lemon oil, lime oil, orange oil, fir needle oil, galbanum oil, geranium oil, grapefruit oil, pine needle oil, caraway oil, labdanum oil, lovage oil, marjoram oil, mandarin oil, clary sage oil, nutmeg oil, myrtle oil, clove oil, neroli oil, patchouli oil, sandalwood oil, thyme oil, verbena oil, vetiver oil and wintergreen oil.

The number of different fragrant components contained in the fragrance formulation will generally be at least 4, preferably at least 6, more preferably at least 8 and most preferably at least 10, such as from 10 to 200 and more preferably from 10 to 100.

Typically, no single fragrant component will comprise more than 70% by weight of the total weight of the fragrance formulation. Preferably no single fragrant component will comprise more than 60% by weight of the total weight of the fragrance formulation and more preferably no single fragrant component will comprise more than 50% by weight of the total weight of the fragrance formulation.

The term“fragrance formulation” in the context of this invention denotes the fragrant components as defined above, plus any optional excipients. Excipients may be included within fragrance formulations for various purposes, for example as solvents for insoluble or poorly-soluble components, as diluents for the more potent components or to control the vapour pressure and evaporation characteristics of the fragrance formulation.

Excipients may have many of the characteristics of fragrant components but they do not have strong odours in themselves. Accordingly, excipients may be distinguished from fragrant components because they can be added to fragrance formulations in high proportions such as 30% or even 50% by weight of the total weight of the fragrance formulation without significantly changing the odour quality of the fragrance formulation. Some examples of suitable excipients include ethanol, isopropanol, diethylene glycol monoethyl ether, dipropylene glycol, diethyl phthalate and triethyl citrate. Mixtures of any of the above described materials may also be suitable. A suitable fragrance formulation for use in the invention comprises a blend of at least 10 fragrant components selected from hydrocarbons i); aliphatic and araliphatic alcohols ii); aliphatic aldehydes and their acetals iv); aliphatic carboxylic acids and esters thereof viii); acyclic terpene alcohols ix); cyclic terpene aldehydes and ketones xii); cyclic and cycloaliphatic ethers xiii); esters of cyclic alcohols xvi); esters of araliphatic alcohols and aliphatic carboxylic acids xviii); araliphatic ethers and their acetals xix); aromatic and araliphatic aldehydes and ketones xx) and aromatic and araliphatic carboxylic acids and esters thereof xxi); as are further described and exemplified above.

The content of fragrant components preferably ranges from 50 to 100%, more preferably from 60 to 100% and most preferably from 75 to 100% by weight based on the total weight of the fragrance formulation; with one or more excipients (as described above) making up the balance of the fragrance formulation as necessary.

The fragrance formulation will typically comprise from about 10 to about 60% and preferably from about 20 to about 40% by weight based on the total weight of the benefit agent delivery particle. The amount of fragrance formulation may be measured by taking a slurry of the benefit agent delivery particles, extracting into ethanol and measuring by liquid chromatography.

The benefit agent delivery particles of the invention are suitable for incorporation into laundry treatment compositions of all physical forms.

In a typical laundry treatment composition according to the invention the level of benefit agent delivery particles will generally range from 0.01 to 10%, preferably from 0.1 to 5%, more preferably from 0.3 to 3% (by weight based on the total weight of the composition).

Product Form

A laundry treatment composition according to the invention is preferably in liquid form.

The term“liquid” in the context of this invention denotes that a continuous phase or predominant part of the composition is liquid and that the composition is flowable at 15°C and above. Accordingly, the term“liquid” may encompass emulsions, suspensions, and compositions having flowable yet stiffer consistency, known as gels or pastes. The viscosity of the composition may suitably range from about 200 to about 10,000 mPa.s at 25°C at a shear rate of 21 sec¹. This shear rate is the shear rate that is usually exerted on the liquid when poured from a bottle. Pourable liquid compositions generally have a viscosity of from 200 to 2,500 mPa.s, preferably from 200 to 1500 mPa.s.

Liquid compositions which are pourable gels generally have a viscosity of from 1 ,500 mPa.s to 6,000 mPa.s, preferably from 1 ,500 mPa.s to 2,000 mPa.s.

Product Types

Preferably the laundry treatment composition according to the invention is a laundry detergent.

Laundry detergents

The term“laundry detergent” in the context of this invention denotes formulated compositions intended for and capable of wetting and cleaning domestic laundry such as clothing, linens and other household textiles. The term“linen” is often used to describe certain types of laundry items including bed sheets, pillow cases, towels, tablecloths, table napkins and uniforms. Textiles can include woven fabrics, non-woven fabrics, and knitted fabrics; and can include natural or synthetic fibres such as silk fibres, linen fibres, cotton fibres, polyester fibres, polyamide fibres such as nylon, acrylic fibres, acetate fibres, and blends thereof including cotton and polyester blends.

Examples of laundry detergents include heavy-duty detergents for use in the wash cycle of automatic washing machines, as well as fine wash and colour care detergents such as those suitable for washing delicate garments (e.g. those made of silk or wool) either by hand or in the wash cycle of automatic washing machines.

To provide cleaning effect, a laundry detergent according to the invention generally comprises at least 3%, such as from 5 to 60% (by weight based on the total weight of the composition) of one or more detersive surfactants. The choice of detersive surfactant, and the amount present, will depend on the intended use of the laundry detergent. For example, different surfactant systems may be chosen for hand-washing products and for products intended for use in different types of automatic washing machine. The total amount of surfactant present will also depend on the intended end use and may, in fully formulated products, be as high as 60% (by weight based on the total weight of the composition) in a composition for washing fabrics by hand. In compositions for machine washing of fabrics, an amount of from 5 to 40%, such as 15 to 35% (by weight based on the total weight of the composition) is generally appropriate.

The term“detersive surfactant” in the context of this invention denotes a surfactant which provides a detersive (i.e. cleaning) effect to laundry treated as part of a domestic laundering process.

Preferred detersive surfactants may be selected from non-soap anionic surfactants, nonionic surfactants and mixtures thereof.

Non-soap anionic surfactants are principally used to facilitate particulate soil removal. Non-soap anionic surfactants for use in the invention are typically salts of organic sulfates and sulfonates having alkyl radicals containing from about 8 to about 22 carbon atoms, the term“alkyl” being used to include the alkyl portion of higher acyl radicals. Examples of such materials include alkyl sulfates, alkyl ether sulfates, alkaryl sulfonates, alpha- olefin sulfonates and mixtures thereof. The alkyl radicals preferably contain from 10 to 18 carbon atoms and may be unsaturated. The alkyl ether sulfates may contain from one to ten ethylene oxide or propylene oxide units per molecule, and preferably contain one to three ethylene oxide units per molecule. The counterion for anionic surfactants is generally an alkali metal such as sodium or potassium; or an ammoniacal counterion such as monoethanolamine, (MEA) diethanolamine (DEA) or triethanolamine (TEA). Mixtures of such counterions may also be employed.

A preferred class of non-soap anionic surfactant for use in the invention includes alkylbenzene sulfonates, particularly linear alkylbenzene sulfonates (LAS) with an alkyl chain length of from 10 to 18 carbon atoms. Commercial LAS is a mixture of closely related isomers and homologues alkyl chain homologues, each containing an aromatic ring sulfonated at the“para” position and attached to a linear alkyl chain at any position except the terminal carbons. The linear alkyl chain typically has a chain length of from 11 to 15 carbon atoms, with the predominant materials having a chain length of about C12. Each alkyl chain homologue consists of a mixture of all the possible sulfophenyl isomers except for the 1-phenyl isomer. LAS is normally formulated into compositions in acid (i.e. HLAS) form and then at least partially neutralized in-situ.

Also suitable are alkyl ether sulfates having a straight or branched chain alkyl group having 10 to 18, more preferably 12 to 14 carbon atoms and containing an average of 1 to 3EO units per molecule. A preferred example is sodium lauryl ether sulfate (SLES) in which the predominantly C12 lauryl alkyl group has been ethoxylated with an average of 3EO units per molecule.

Some alkyl sulfate surfactant (PAS) may be used, such as non-ethoxylated primary and secondary alkyl sulphates with an alkyl chain length of from 10 to 18.

Mixtures of any of the above described materials may also be used. A preferred mixture of non-soap anionic surfactants for use in the invention comprises linear alkylbenzene sulfonate (preferably Cn to C1₅ linear alkyl benzene sulfonate) and sodium lauryl ether sulfate (preferably C1₀ to C1₈ alkyl sulfate ethoxylated with an average of 1 to 3 EO).

In a laundry detergent according to the invention, the total level of non-soap anionic surfactant may suitably range from 5 to 30% (by weight based on the total weight of the composition).

Nonionic surfactants may provide enhanced performance for removing very hydrophobic oily soil and for cleaning hydrophobic polyester and polyester/cotton blend fabrics.

Nonionic surfactants for use in the invention are typically polyoxyalkylene compounds, i.e. the reaction product of alkylene oxides (such as ethylene oxide or propylene oxide or mixtures thereof) with starter molecules having a hydrophobic group and a reactive hydrogen atom which is reactive with the alkylene oxide. Such starter molecules include alcohols, acids, amides or alkyl phenols. Where the starter molecule is an alcohol, the reaction product is known as an alcohol alkoxylate. The polyoxyalkylene compounds can have a variety of block and heteric (random) structures. For example, they can comprise a single block of alkylene oxide, or they can be diblock alkoxylates or triblock alkoxylates. Within the block structures, the blocks can be all ethylene oxide or all propylene oxide, or the blocks can contain a heteric mixture of alkylene oxides. Examples of such materials include Cs to C22 alkyl phenol ethoxylates with an average of from 5 to 25 moles of ethylene oxide per mole of alkyl phenol; and aliphatic alcohol ethoxylates such as Cs to Ci₈ primary or secondary linear or branched alcohol ethoxylates with an average of from 2 to 40 moles of ethylene oxide per mole of alcohol.

A preferred class of nonionic surfactant for use in the invention includes aliphatic Cs to Ci₈, more preferably C12 to C15 primary linear alcohol ethoxylates with an average of from 3 to 20, more preferably from 5 to 10 moles of ethylene oxide per mole of alcohol.

Mixtures of any of the above described materials may also be used.

In a laundry detergent according to the invention, the total level of nonionic surfactant may suitably range from 0 to 25% (by weight based on the total weight of the

composition).

A laundry detergent according to the invention is preferably in liquid form.

A liquid laundry detergent according to the invention may generally comprise from 5 to 95%, preferably from 10 to 90%, more preferably from 15 to 85% water (by weight based on the total weight of the composition). The composition may also incorporate non- aqueous carriers such as hydrotropes, co-solvents and phase stabilizers. Such materials are typically low molecular weight, water-soluble or water-miscible organic liquids such as C1 to C5 monohydric alcohols (such as ethanol and n- or i-propanol); C2 to C6 diols (such as monopropylene glycol and dipropylene glycol); C3 to C9 triols (such as glycerol); polyethylene glycols having a weight average molecular weight (M_w) ranging from about 200 to 600; C1 to C3 alkanolamines such as mono-, di- and triethanolamines; and alkyl aryl sulfonates having up to 3 carbon atoms in the lower alkyl group (such as the sodium and potassium xylene, toluene, ethylbenzene and isopropyl benzene (cumene) sulfonates).

Mixtures of any of the above described materials may also be used.

Non-aqueous carriers, when included in a liquid laundry detergent according to the invention, may be present in an amount ranging from 0.1 to 20%, preferably from 1 to 15%, and more preferably from 3 to 12% (by weight based on the total weight of the composition). Builders

A laundry detergent according to the invention may contain one or more builders. Builders enhance or maintain the cleaning efficiency of the surfactant, primarily by reducing water hardness. This is done either by sequestration or chelation (holding hardness minerals in solution), by precipitation (forming an insoluble substance), or by ion exchange (trading electrically charged particles).

Builders for use in the invention can be of the organic or inorganic type, or a mixture thereof. Non-phosphate builders are preferred.

Inorganic, non-phosphate builders for use in the invention include hydroxides, carbonates, silicates, zeolites, and mixtures thereof.

Suitable hydroxide builders for use in the invention include sodium and potassium hydroxide.

Suitable carbonate builders for use in the invention include mixed or separate, anhydrous or partially hydrated alkali metal carbonates, bicarbonates or sesquicarbonates.

Preferably the alkali metal is sodium and/or potassium, with sodium carbonate being particularly preferred.

Suitable silicate builders include amorphous forms and/or crystalline forms of alkali metal (such as sodium) silicates. Preferred are crystalline layered sodium silicates

(phyllosilicates) of the general formula (I)

NaMSi_x0_2x+i.yH₂0 (I)

in which M is sodium or hydrogen, x is a number from 1.9 to 4, preferably 2 or 3 and y is a number from 0 to 20. Sodium disilicates of the above formula in which M is sodium and x is 2 are particularly preferred. Such materials can be prepared with different crystal structures, referred to as a, b, y and d phases, with d-sodium disilicate being most preferred. Zeolites are naturally occurring or synthetic crystalline aluminosilicates composed of (Si0₄)⁴ and (AI0₄)⁵ tetrahedra, which share oxygen-bridging vertices and form cage-like structures in crystalline form. The ratio between oxygen, aluminium and silicon is 0:(AI + Si) = 2:1. The frameworks acquire their negative charge by substitution of some Si by Al. The negative charge is neutralised by cations and the frameworks are sufficiently open to contain, under normal conditions, mobile water molecules. Suitable zeolite builders for use in the invention may be defined by the general formula (II):

Na_x[(AI0₂)_x(Si0₂)y]-zH₂0 (II)

in which x and y are integers of at least 6, the molar ratio of x to y is in the range from about 1 to about 0.5, and z is an integer of at least 5, preferably from about 7.5 to about 276, more preferably from about 10 to about 264.

Preferred inorganic, non-phosphate builders for use in the invention may be selected from zeolites (of the general formula (II) defined above), sodium carbonate, d-sodium disilicate and mixtures thereof.

Suitable organic, non-phosphate builders for use in the invention include

polycarboxylates, in acid and/or salt form. When utilized in salt form, alkali metal (e.g. sodium and potassium) or alkanolammonium salts are preferred. Specific examples of such materials include sodium and potassium citrates, sodium and potassium tartrates, the sodium and potassium salts of tartaric acid monosuccinate, the sodium and potassium salts of tartaric acid disuccinate, sodium and potassium

ethylenediaminetetraacetates, sodium and potassium N(2-hydroxyethyl)-ethylenediamine triacetates, sodium and potassium nitrilotriacetates and sodium and potassium N-(2- hydroxyethyl)-nitrilodiacetates. Polymeric polycarboxylates may also be used, such as polymers of unsaturated monocarboxylic acids (e.g. acrylic, methacrylic, vinylacetic, and crotonic acids) and/or unsaturated dicarboxylic acids (e.g. maleic, fumaric, itaconic, mesaconic and citraconic acids and their anhydrides). Specific examples of such materials include polyacrylic acid, polymaleic acid, and copolymers of acrylic and maleic acid. The polymers may be in acid, salt or partially neutralised form and may suitably have a molecular weight (Mw) ranging from about 1 ,000 to 100,000, preferably from about 2,000 to about 85,000, and more preferably from about 2,500 to about 75,000. Preferred organic, non-phosphate builders for builders for use in the invention may be selected from polycarboxylates (e.g. citrates) in acid and/or salt form and mixtures thereof.

Mixtures of any of the above described materials may also be used.

Preferably the level of phosphate builders in a laundry detergent of the invention is no more than 1 %, more preferably no more than 0.1% and most preferably 0% (by weight based on the total weight of the composition). The term“phosphate builder” in the context of this invention denotes alkali metal, ammonium and alkanolammonium salts of polyphosphate, orthophosphate, and/or metaphosphate (e.g. sodium tripolyphosphate).

The overall level of builder, when included, may range from about 0.1 to about 80%, preferably from about 0.5 to about 50% (by weight based on the total weight of the composition).

Polymeric cleaning boosters

A laundry detergent according to the invention may also include one or more polymeric cleaning boosters such as antiredeposition polymers, soil release polymers and mixtures thereof.

Anti-redeposition polymers stabilise the soil in the wash solution thus preventing redeposition of the soil. Suitable anti-redeposition polymers for use in the invention include alkoxylated polyethyleneimines. Polyethyleneimines are materials composed of ethylene imine units -CH2CH2NH- and, where branched, the hydrogen on the nitrogen is replaced by another chain of ethylene imine units. Preferred alkoxylated

polyethylenimines for use in the invention have a polyethyleneimine backbone of about 300 to about 10000 weight average molecular weight (M_w). The polyethyleneimine backbone may be linear or branched. It may be branched to the extent that it is a dendrimer. The alkoxylation may typically be ethoxylation or propoxylation, or a mixture of both. Where a nitrogen atom is alkoxylated, a preferred average degree of alkoxylation is from 10 to 30, preferably from 15 to 25 alkoxy groups per modification. A preferred material is ethoxylated polyethyleneimine, with an average degree of ethoxylation being from 10 to 30, preferably from 15 to 25 ethoxy groups per ethoxylated nitrogen atom in the polyethyleneimine backbone. Another type of suitable anti-redeposition polymer for use in the invention includes cellulose esters and ethers, for example sodium

carboxymethyl cellulose.

Mixtures of any of the above described materials may also be used.

The overall level of anti-redeposition polymer, when included, may range from 0.05 to 6%, more preferably from 0.1 to 5% (by weight based on the total weight of the composition).

Soil release polymers help to improve the detachment of soils from fabric by modifying the fabric surface during washing. The adsorption of a SRP over the fabric surface is promoted by an affinity between the chemical structure of the SRP and the target fibre.

SRPs for use in the invention may include a variety of charged (e.g. anionic) as well as non-charged monomer units and structures may be linear, branched or star-shaped. The SRP structure may also include capping groups to control molecular weight or to alter polymer properties such as surface activity. The weight average molecular weight (M_w) of the SRP may suitably range from about 1000 to about 20,000 and preferably ranges from about 1500 to about 10,000.

SRPs for use in the invention may suitably be selected from copolyesters of dicarboxylic acids (for example adipic acid, phthalic acid or terephthalic acid), diols (for example ethylene glycol or propylene glycol) and polydiols (for example polyethylene glycol or polypropylene glycol). The copolyester may also include monomeric units substituted with anionic groups, such as for example sulfonated isophthaloyl units. Examples of such materials include oligomeric esters produced by transesterification/oligomerization of poly(ethyleneglycol) methyl ether, dimethyl terephthalate (“DMT”), propylene glycol (“PG”) and poly(ethyleneglycol) (“PEG”); partly- and fully-anionic-end-capped oligomeric esters such as oligomers from ethylene glycol (“EG”), PG, DMT and Na-3,6-dioxa-8- hydroxyoctanesulfonate; nonionic-capped block polyester oligomeric compounds such as those produced from DMT, Me-capped PEG and EG and/or PG, or a combination of DMT, EG and/or PG, Me-capped PEG and Na-dimethyl-5-sulfoisophthalate, and copolymeric blocks of ethylene terephthalate or propylene terephthalate with polyethylene oxide or polypropylene oxide terephthalate

Other types of SRP for use in the invention include cellulosic derivatives such as hydroxyether cellulosic polymers, Ci-C4 alkylcelluloses and C₄ hydroxyalkyl celluloses; polymers with poly(vinyl ester) hydrophobic segments such as graft copolymers of poly(vinyl ester), for example C1-C6 vinyl esters (such as poly(vinyl acetate)) grafted onto polyalkylene oxide backbones; poly(vinyl caprolactam) and related co-polymers with monomers such as vinyl pyrrolidone and/or dimethylaminoethyl methacrylate; and polyester-polyamide polymers prepared by condensing adipic acid, caprolactam, and polyethylene glycol.

Preferred SRPs for use in the invention include copolyesters formed by condensation of terephthalic acid ester and diol, preferably 1 ,2 propanediol, and further comprising an end cap formed from repeat units of alkylene oxide capped with an alkyl group. Examples of such materials have a structure corresponding to general formula (I):

in which R¹ and R² independently of one another are X-(OC2H4)_n-(OC3H6)_{m ;}

in which X is C1-4 alkyl and preferably methyl;

n is a number from 12 to 120, preferably from 40 to 50;

m is a number from 1 to 10, preferably from 1 to 7; and

a is a number from 4 to 9.

Because they are averages, m, n and a are not necessarily whole numbers for the polymer in bulk.

Mixtures of any of the above described materials may also be used.

The overall level of SRP, when included, may range from 0.1 to 10%, preferably from 0.3 to 7%, more preferably from 0.5 to 5% (by weight based on the total weight of the composition). Transition metal ion chelating agents

A liquid or particulate laundry detergent according to the invention may contain one or more chelating agents for transition metal ions such as iron, copper and manganese. Such chelating agents may help to improve the stability of the composition and protect for example against transition metal catalysed decomposition of certain ingredients.

Suitable transition metal ion chelating agents include phosphonates, in acid and/or salt form. When utilized in salt form, alkali metal (e.g. sodium and potassium) or

alkanolammonium salts are preferred. Specific examples of such materials include aminotris(methylene phosphonic acid) (ATMP), 1-hydroxyethylidene diphosphonic acid (HEDP) and diethylenetriamine penta(methylene phosphonic acid (DTPMP) and their respective sodium or potassium salts. HEDP is preferred. Mixtures of any of the above described materials may also be used.

Transition metal ion chelating agents, when included, may be present in an amount ranging from about 0.1 to about 10%, preferably from about 0.1 to about 3% (by weight based on the total weight of the composition).

Fatty Acid

A laundry detergent according to the invention may in some cases contain one or more fatty acids and/or salts thereof.

Suitable fatty acids in the context of this invention include aliphatic carboxylic acids of formula RCOOH, where R is a linear or branched alkyl or alkenyl chain containing from 6 to 24, more preferably 10 to 22, most preferably from 12 to 18 carbon atoms and 0 or 1 double bond. Preferred examples of such materials include saturated C12-18 fatty acids such as lauric acid, myristic acid, palmitic acid or stearic acid; and fatty acid mixtures in which 50 to 100% (by weight based on the total weight of the mixture) consists of saturated C12-18 fatty acids. Such mixtures may typically be derived from natural fats and/or optionally hydrogenated natural oils (such as coconut oil, palm kernel oil or tallow). The fatty acids may be present in the form of their sodium, potassium or ammonium salts and/or in the form of soluble salts of organic bases, such as mono-, di- or triethanolamine.

Mixtures of any of the above described materials may also be used.

Fatty acids and/or their salts, when included, may be present in an amount ranging from about 0.25 to 5%, more preferably from 0.5 to 5%, most preferably from 0.75 to 4% (by weight based on the total weight of the composition).

For formula accounting purposes, in the formulation, fatty acids and/or their salts (as defined above) are not included in the level of surfactant or in the level of builder.

Rheology modifiers

A liquid laundry detergent according to the invention may comprise one or more rheology modifiers. Examples of such materials include polymeric thickeners and/or structurants such as hydrophobically modified alkali swellable emulsion (HASE) copolymers.

Exemplary HASE copolymers for use in the invention include linear or crosslinked copolymers that are prepared by the addition polymerization of a monomer mixture including at least one acidic vinyl monomer, such as (meth)acrylic acid (i.e. methacrylic acid and/or acrylic acid); and at least one associative monomer. The term“associative monomer” in the context of this invention denotes a monomer having an ethylenically unsaturated section (for addition polymerization with the other monomers in the mixture) and a hydrophobic section. A preferred type of associative monomer includes a polyoxyalkylene section between the ethylenically unsaturated section and the

hydrophobic section. Preferred HASE copolymers for use in the invention include linear or crosslinked copolymers that are prepared by the addition polymerization of (meth)acrylic acid with (i) at least one associative monomer selected from linear or branched C8-C40 alkyl (preferably linear C12-C22 alkyl) polyethoxylated (meth)acrylates; and (ii) at least one further monomer selected from C1-C4 alkyl (meth) acrylates, polyacidic vinyl monomers (such as maleic acid, maleic anhydride and/or salts thereof) and mixtures thereof. The polyethoxylated portion of the associative monomer (i) generally comprises about 5 to about 100, preferably about 10 to about 80, and more preferably about 15 to about 60 oxyethylene repeating units. Mixtures of any of the above described materials may also be used.

Polymeric thickeners, when included, may be present in an amount ranging from 0.1 to 5% (by weight based on the total weight of the composition).

A liquid laundry detergent according to the invention may also have its rheology modified by use of one or more external structurants which form a structuring network within the composition. Examples of such materials include hydrogenated castor oil, microfibrous cellulose and citrus pulp fibre. The presence of an external structurant may provide shear thinning rheology and may also enable materials such as encapsulates and visual cues to be suspended stably in the liquid.

Enzymes

A laundry detergent according to the invention may comprise an effective amount of one or more enzymes selected from the group comprising, pectate lyase, protease, amylase, cellulase, lipase, mannanase and mixtures thereof. The enzymes are preferably present with corresponding enzyme stabilizers.

A liquid laundry detergent according to the invention preferably has a pH in the range of 5 to 9, more preferably 6 to 8, when measured on dilution of the composition to 1 % (by weight based on the total weight of the composition) using demineralised water.

Further Optional Ingredients

A laundry treatment composition of the invention may contain further optional ingredients to enhance performance and/or consumer acceptability. Examples of such ingredients include foam boosting agents, preservatives (e.g. bactericides), antioxidants, sunscreens, anticorrosion agents, colorants, pearlisers and/or opacifiers, and shading dye. Each of these ingredients will be present in an amount effective to accomplish its purpose.

Generally, these optional ingredients are included individually at an amount of up to 5% (by weight based on the total weight of the composition). Packaging and dosing

A laundry treatment composition of the invention may be packaged as unit doses in polymeric film soluble in the wash water. Alternatively, a composition of the invention may be supplied in multidose plastics packs with a top or bottom closure. A dosing measure may be supplied with the pack either as a part of the cap or as an integrated system.

A method of treating fabric using a laundry detergent according to the invention will usually involve diluting the dose of detergent to obtain a wash liquor, and washing fabrics with the wash liquor so formed. The method of laundering fabric may suitably be carried out in an automatic washing machine, or can be carried out by hand.

In automatic washing machines, the dose of detergent is typically put into a dispenser and from there it is flushed into the machine by the water flowing into the machine, thereby forming the wash liquor. Alternatively, the dose of detergent may be added directly into the drum. Dosages for a typical front-loading washing machine (using 10 to 15 litres of water to form the wash liquor) may range from about 10 ml to about 60 ml, preferably about 15 to 40 ml. Dosages for a typical top-loading washing machine (using from 40 to 60 litres of water to form the wash liquor) may be higher, e.g. up to about 100 ml. Lower dosages of detergent (e.g. 50 ml or less) may be used for hand washing methods (using about 1 to 10 litres of water to form the wash liquor). A subsequent aqueous rinse step and drying the laundry is preferred. Any input of water during any optional rinsing step(s) is not included when determining the volume of the wash liquor.

The laundry drying step can take place either in an automatic dryer or in the open air.

The invention will now be further described with reference to the following non-limiting Examples. EXAMPLES

All weight percentages are by weight based on total weight unless otherwise specified.

Melamine-formaldehyde core-shell particles were prepared having a shell of melamine- formaldehyde and a core containing a 15-component model fragrance, an average particle diameter of approximately 13pm and a zeta potential of approximately -20mV (when measured as described above). The particles were obtained in an aqueous slurry having a solids content of about 30 wt.%.

Example 1

0.7g of the aqueous slurry of core-shell particles was diluted with 25g water, and the diluted slurry placed in a reaction vessel. Coating was achieved using a two-stage process involving the sequential addition of coating ingredients (melamine and folic acid) using a 50% weight ratio of coating ingredients to core-shell particles. To form the coating, melamine is added to the slurry of core-shell particles in the reaction vessel and the mixture stirred for 10 minutes at 70°C. Folic acid is then added to the reaction vessel and the mixture stirred for 10 minutes at 70°C. The mixing of melamine and folic acid forms a complex. The mixture is cooled down in ice and the complex precipitates onto the surface of the core-shell particles to form a coating.

Successful coating of the core-shell particles was corroborated with high resolution SEM imaging.

Example 2

The aqueous slurry was diluted (x4) with water, and placed in a reaction vessel and heated to 62°C. The coating ingredients (melamine and BTCA) were added to the slurry of core-shell particles in the reaction vessel using a 50% weight ratio of coating ingredients to core-shell particles. The mixing of melamine and BTCA forms a complex. The complex precipitates onto the surface of the core-shell particles on cooling to form a coating. Control

0.7g of the aqueous slurry was diluted with 25g water, and stirred for 15 minutes at 70°C, followed by cooling down in ice. No coating ingredients were added. To test the leakage of fragrance from the core-shell particles, 1 ml of test particle slurry was mixed with 9ml of laundry liquid having ingredients shown in Table 1.

Table 1

Each test mixture was then placed on a roller for 24 hours, followed by centrifugation for 30 minutes at H OOOrpm. The supernatant liquid was then removed and filtered through a 3.1 pm filter. 1 ml of the filtrate was then placed in a 20ml headspace vial. The headspace above the filtrate was measured after incubation for 10 minutes at 40°C on a CombiPAL autosampler. Sampling was achieved using a PDMS/Carboxen/DVB fibre with an exposure time of 60 seconds. The fibre was then desorbed for 5 minutes at 270°C in the inlet of an Agilent 6890 gas chromatograph. Separation was achieved using a 30m BPX-5 capillary column. Peak identification was achieved using an Agilent 5973N inert mass detector in conjunction with the appropriate software/NIST library. Integrations for the peaks from the fragrance were summed to give a total fragrance level. A calibration plot, constructed by adding known amounts of free fragrance to the model laundry liquid, allowed the result to be converted into a percentage leakage figure.

The results showed that the coated particles of Example 1 according to the invention gave a 25% reduction in fragrance leakage compared to the uncoated control particles when incorporated into laundry liquid. The coated particles of Example 2 according to the invention gave a 9% reduction in fragrance leakage compared to the uncoated control particles when incorporated into laundry liquid.

When the laundry liquid is diluted in a washing operation (typically 35ml liquid into 21 L water) the coatings are removed.

In this way, the particles of the invention provide an improvement in the stability of the fragrance toward leakage in product, whilst providing an enhanced fragrance experience in the early stages post wash.

Claims

1. A benefit agent delivery particle having a core-shell structure in which a porous shell of polymeric material entraps a core containing the benefit agent; in which the pores in the shell are at least partially occluded by a wash-removable coating provided at the exterior surface of the shell; and characterized in that the wash- removable coating is formed from deposited melamine/acid complex.

2. A particle according to claim 1 , in which the benefit agent is a fragrance

formulation comprising a blend of at least 10 fragrant components selected from hydrocarbons; aliphatic and araliphatic alcohols; aliphatic aldehydes and their acetals; aliphatic carboxylic acids and esters thereof; acyclic terpene alcohols; cyclic terpene aldehydes and ketones; cyclic and cycloaliphatic ethers; esters of cyclic alcohols; esters of araliphatic alcohols and aliphatic carboxylic acids;

araliphatic ethers and their acetals; aromatic and araliphatic aldehydes and ketones; and aromatic and araliphatic carboxylic acids and esters thereof.

3. A particle according to claim 1 or claim 2, in which the fragrance formulation

comprises from 20 to 40% by weight based on the total weight of the benefit agent delivery particle.

4. A particle according to any one of claims 1 to 3, in which the melamine/acid

complex has a solubility in distilled water (at 25°C and at atmospheric pressure) of less than 10mg/L.

5. A particle according to claim 4, in which the melamine/acid complex is derived from the association of melamine with a multifunctional organic acid.

6. A particle according to claim 5, in which the melamine/acid complex corresponds to the following general formula (I):

7. A process of preparing a benefit agent delivery particle as defined in any one of claims 1 to 6, in which the melamine, followed by the multifunctional organic acid, are mixed into a slurry of pre-formed core-shell particles.

8. A process according to claim 7, in which the slurry of pre-formed core-shell

particles is a dilute aqueous slurry with a water content of at least 80% (by weight based on total weight).

9. A process according to claim 7 or claim 8, in which the melamine and the

multifunctional organic acid are mixed in a molar ratio of from 2:1 to 10:1.

10. A laundry treatment composition comprising a benefit agent delivery particle as defined in any one of claims 1 to 6.