Field of the Invention
The present invention relates to particulate laundry detergents which contain fragrance, and especially concerns particulate laundry detergents which contain a combination of encapsulated and free fragrance.
Background and Prior Art
In particulate laundry detergents such as laundry detergent powders, 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. However, there is equally a desire to reduce manufacturing costs and raw material wastage, particularly in the case of high value ingredients such as fragrances.
The present invention addresses this problem.
Summary of the Invention
The present invention provides a particulate laundry detergent composition comprising:
- a) from 3 to 60% by weight based on the total weight of the composition of one or more detersive surfactants selected from non-soap anionic surfactants, nonionic surfactants and mixtures thereof;
- b) from 0.01 to 1% by weight based on the total weight of the composition of a fragrance formulation (f1) which is in the form of free droplets dispersed in the composition;
- c) from 0.01 to 1% by weight based on the total weight of the composition of a fragrance formulation (f2) which is entrapped within discrete polymeric microparticles dispersed in the composition;
in which the total amount of fragrance formulation (f1) and fragrance formulation (f2) ranges from 0.05 to 1.5% by weight based on the total weight of the composition; and in which the weight ratio of fragrance formulation (f1) to fragrance formulation (f2) in the composition ranges from of 60:40 to 30:70.
Detailed Description and Preferred Embodiments
Fragrance formulation (f1)
The fragrance formulation (f1) 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, α-pinene, β-pinene, α-terpinene, γ-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, α-sinensal, β-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, α-ionone, β-ionone, α-n-methylionone, β-n-methylionone, α-isomethylionone, β-isomethylionone, alpha-irone, α-damascone, β-damascone, β-damascenone, δ-damascone, γ-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-trimethyl-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, α-trichloromethylbenzyl acetate, α,α-dimethylphenylethyl acetate, α,α-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)-1H-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
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 constiuents 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 (f1) 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 fragrance formulation (f1). Preferably no single fragrant component will comprise more than 60% by weight of the total weight of fragrance formulation (f1) and more preferably no single fragrant component will comprise more than 50% by weight of the total weight of fragrance formulation (f1).
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 (f1) 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 fragrance formulation (f1); with one or more excipients (as described above) making up the balance of the fragrance formulation (f1) as necessary.
Fragrance formulation (f1) is in the form of free droplets dispersed in the composition. The term "free droplets" in the context of this invention denotes droplets which are not entrapped within discrete polymeric microparticles.
In a typical particulate laundry detergent composition according to the invention the level of fragrance formulation (f1) preferably ranges from 0.05 to 0.15% (by weight based on the total weight of the composition).
Fragrance formulation (f2)
A fragrance formulation (f2) for use in the invention will typically contain a blend of selected fragrant components, optionally mixed with one or more excipients, as described above for fragrance formulation (f1).
Fragrance formulation (f2) and fragrance formulation (f1) may be the same or different.
Fragrance formulation (f2) is entrapped within discrete polymeric microparticles dispersed in the composition. One type of microparticle suitable for use in the invention is a microcapsule. Microencapsulation may be defined as the process of surrounding or enveloping one substance within another substance on a very small scale, yielding capsules ranging from less than one micron to several hundred microns in size. The material that is encapsulated may be called the core, the active ingredient or agent, fill, payload, nucleus, or internal phase. The material encapsulating the core may be referred to as the coating, membrane, shell, or wall material.
Microcapsules typically have at least one generally spherical continuous shell surrounding the core. The shell may contain pores, vacancies or interstitial openings depending on the materials and encapsulation techniques employed. Multiple shells may be made of the same or different encapsulating materials, and may be arranged in strata of varying thicknesses around the core. Alternatively, the microcapsules may be asymmetrically and variably shaped with a quantity of smaller droplets of core material embedded throughout the microcapsule.
The shell may have a barrier function protecting the core material from the environment external to the microcapsule, but it may also act as a means of modulating the release of core materials such as fragrance. Thus, a shell may be water soluble or water swellable and fragrance release may be actuated in response to exposure of the microcapsules to a moist environment. Similarly, if a shell is temperature sensitive, a microcapsule might release fragrance in response to elevated temperatures. Microcapsules may also release fragrance in response to shear forces applied to the surface of the microcapsules.
A preferred type of polymeric microparticle suitable for use in the invention is a polymeric core-shell microcapsule in which at least one generally spherical continuous shell of polymeric material surrounds a core containing the fragrance formulation (f2). The shell will typically comprise at most 20% by weight based on the total weight of the microcapsule. The fragrance formulation (f2) 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 microcapsule. The amount of fragrance (f2) may be measured by taking a slurry of the microcapsules, extracting into ethanol and measuring by liquid chromatography.
Polymeric core-shell microcapsules for use in the invention may be prepared 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 microcapsule and the dimensions of the dispersed droplets directly determine the size of the subsequent microcapsules. Microcapsule 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 and form core-shell microcapsules. An example of a core-shell microcapsule produced by this method is a polyurea microcapsule with a 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 capsules of a desired 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 microcapsules. An example of a core-shell microcapsule produced by this method is an aminoplast microcapsule with a 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 copolymers of maleic anhydride.
One example of a preferred polymeric core-shell microcapsule for use in the invention is an aminoplast microcapsule with an aminoplast shell surrounding a core containing the fragrance formulation (f2). More preferably such an aminoplast shell is formed from the polycondensation product of melamine with formaldehyde.
Polymeric microparticles suitable for use in 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 a typical size range of 100 to 600 nanometers. The preferred particle size range is in the micron range. Examples of particles in the micron range include polymeric core-shell microcapsules (such as those further described above) with a typical size range of 1 to 50 microns, preferably 5 to 30 microns. The average particle size can be determined by light scattering using a Malvern Mastersizer with the average particle size being taken as the median particle size D (0.5) value. The particle size distribution can be narrow, broad or multimodal. If necessary, the microcapsules as initially produced may be filtered or screened to produce a product of greater size uniformity.
Polymeric microparticles suitable for use in the invention may be provided with a deposition aid at the outer surface of the microparticle. Deposition aids serve to modify the properties of the exterior of the microparticle, for example to make the microparticle 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 outer surface of the microparticle by means of covalent bonding, entanglement or strong adsorption. Examples include polymeric core-shell microcapsules (such as those further described above) in which a deposition aid is attached to the outside of the shell, preferably by means of covalent bonding. While it is preferred that the deposition aid is attached directly to the outside of the shell, it may also be attached 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 β glycan (generalised sugar) backbone structure with at least 4, and preferably at least 10 backbone residues which are β1-4 linked, such as a glucan backbone (consisting of β1-4 linked glucose residues), a mannan backbone (consisting of β1-4 linked mannose residues) or a xylan backbone (consisting of β1-4 linked xylose residues). Examples of such β1-4 linked polysaccharides include xyloglucans, glucomannans, mannans, galactomannans, β(1-3),(1-4) glucan and the xylan family incorporating glucurono-, arabino- and glucuronoarabinoxylans. Preferred β1-4 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 β1-4 linked glucan backbone with side chains of α-D xylopyranose and β-D-galactopyranosyl-(1-2)-α-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 β1-4 linked mannose residues, with single unit galactose side chains linked α1-6 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 (Mw
) 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.
One example of a particularly preferred polymeric core-shell microcapsule for use in the invention is an aminoplast microcapsule with a shell formed by the polycondensation of melamine with formaldehyde; surrounding a core containing the fragrance formulation (f2); in which a deposition aid is attached to the outside of the shell by means of covalent bonding. The preferred deposition aid is selected from β1-4 linked polysaccharides, and in particular the xyloglucans of plant origin, as are further described above.
In a typical particulate laundry detergent composition according to the invention the level of fragrance formulation (f2) preferably ranges from 0.05 to 0.2% (by weight based on the total weight of the composition).
The present inventors have surprisingly observed that it is possible to reduce the total level of fragrance included in the composition of the invention without sacrificing the overall fragrance experience delivered to the consumer at key stages in the laundry process. A reduction in the total level of fragrance is advantageous for cost and environmental reasons.
Accordingly, the total amount of fragrance formulation (f1) and fragrance formulation (f2) in the composition of the invention suitably ranges from 0.1 to 0.5%, preferably from 0.15 to 0.3% (by weight based on the total weight of the composition).
The weight ratio of fragrance formulation (f1) to fragrance formulation (f2) in the composition of the invention preferably ranges from 60:40 to 45:55. Particularly good results have been obtained at a weight ratio of fragrance formulation (f1) to fragrance formulation (f2) of around 50:50.
Particulate 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.
The term "particulate" in the context of this invention denotes free-flowing or compacted solid forms such as powders, granules, pellets, flakes, bars, briquettes or tablets.
One preferred form for the composition according to the invention is a free-flowing powdered solid, with a loose (unpackaged) bulk density generally ranging from about 200g/l to about 1,300 g/l, preferably from about 400 g/l to about 1,000 g/l, more preferably from about 500g/l to about 900 g/l.
The composition of the invention comprises from 3 to 60%, preferably from 10 to 60%, and more preferably from 15 to 50% by weight based on the total weight of the composition of one or more detersive surfactants selected from non-soap anionic surfactants, nonionic surfactants and mixtures thereof.
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.
Non-soap anionic surfactants are principally used to facilitate particulate soil removal. Non-soap anionic surfactants for use in the invention may typically be selected from 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, 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.
Mixtures of any of the above described materials may also be used.
In a composition of the invention the total level of non-soap anionic surfactant may suitably range from 5 to 25% (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 C8
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 C8
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 C8
, more preferably C12
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 composition of the invention the total level of nonionic surfactant may suitably range from 1 to 10% (by weight based on the total weight of the composition).
Examples of suitable mixtures of non-soap anionic and/or nonionic surfactants for use in the invention include mixtures of linear alkylbenzene sulfonate (preferably C11
linear alkyl benzene sulfonate) with sodium lauryl ether sulfate (preferably C10
alkyl sulfate ethoxylated with an average of 1 to 3 EO) and/or ethoxylated aliphatic alcohol (preferably C12
primary linear alcohol ethoxylate with an average of from 5 to 10 moles of ethylene oxide per mole of alcohol). The level of linear alkylbenzene sulfonate (preferably C11
linear alkyl benzene sulfonate) in such mixtures is preferably at least 50%, such as from 50 to 95%(by weight based on the total weight of the mixture).
A composition of the invention may also contain one or more cosurfactants (such as amphoteric (zwitterionic) and/or cationic surfactants) in addition to the non-soap anionic and/or nonionic detersive surfactants described above.
Specific cationic surfactants include C8
alkyl dimethyl ammonium halides and derivatives thereof in which one or two hydroxyethyl groups replace one or two of the methyl groups, and mixtures thereof. Cationic surfactant, when included, may be present in an amount ranging from 0.1 to 5% (by weight based on the total weight of the composition).
Specific amphoteric (zwitterionic) surfactants include alkyl amine oxides, alkyl betaines, alkyl amidopropyl betaines, alkyl sulphobetaines (sultaines), alkyl glycinates, alkyl carboxyglycinates, alkyl amphoacetates, alkyl amphopropionates, alkylamphoglycinates, alkyl amidopropyl hydroxysultaines, acyl taurates and acyl glutamates, 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. Amphoteric (zwitterionic) surfactant, 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 composition of the invention may also include one or more builders. Builders are principally used to reduce 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 can also supply and maintain alkalinity, which assists cleaning, especially of acid soils; help keep removed soil from redepositing during washing; and emulsify oily and greasy soils.
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 carbonates, silicates, zeolites, and mixtures thereof.
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)
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 α, β, γ and δ phases, with δ-sodium disilicate being most preferred.
Zeolites are naturally occurring or synthetic crystalline aluminosilicates composed of (SiO4
tetrahedra, which share oxygen-bridging vertices and form cage-like structures in crystalline form. The ratio between oxygen, aluminium and silicon is O:(Al + 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):
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.
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.
Mixtures of any of the above described materials may also be used. Preferred builders for use in the invention may be selected from zeolites (of the general formula (II) defined above), sodium carbonate, δ-sodium disilicate and mixtures thereof.
Preferably the level of phosphate builders in a composition of the invention is less than 1% (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).
Builder, when included, may be present in a total amount ranging from about 10 to about 80%, preferably from about 15 to 50% (by weight based on the total weight of the composition).
A composition of the invention may also include one or more fillers to assist in providing the desired density and bulk to the composition. Suitable fillers for use in the invention may generally be selected from neutral salts with a solubility in water of at least 1 gram per 100 grams of water at 20° C; such as alkali metal, alkaline earth metal, ammonium or substituted ammonium chlorides, fluorides, acetates and sulfates and mixtures thereof. Preferred fillers for use in the invention include alkali metal (more preferably sodium and/or potassium) sulfates and chlorides and mixtures thereof, with sodium sulfate and/or sodium chloride being most preferred.
Filler, when included, may be present in a total amount ranging from about 1 to about 80%, preferably from about 5 to about 50% (by weight based on the total weight of the composition).
A composition of the invention may 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.
A composition of the invention may also include one or more polymeric cleaning boosters. such as soil release polymers, antiredeposition polymers, and mixtures thereof.
Soil release polymers adsorb onto a fabric surface assisting soil removal. Suitable soil release polymers for use in the invention include 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). An example of such a material has a midblock formed from propylene terephthalate repeat units and one or two end blocks of capped polyalkylene oxide, typically PEG 750 to 2000 with methyl end capping. The weight average molecular weight (Mw
) of such materials generally ranges from about 1000 to about 20,000 and preferably ranges from about 1500 to about 10,000.
Mixtures of any of the above described materials may also be used.
When included, a composition of the invention will preferably comprise from 0.05 to 6%, more preferably from 0.1 to 5% (by weight based on the total weight of the composition) of one or more soil release polymer(s) such as, for example, the copolyesters which are described above.
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 -CH2
NH- 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 (Mw
). 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.
When included, a composition of the invention will preferably comprise from 0.05 to 6%, more preferably from 0.1 to 5% (by weight based on the total weight of the composition) of one or more anti-redeposition polymers such as, for example, the alkoxylated polyethyleneimines and/or cellulose esters and ethers which are described above.
A composition of the invention may also include an oxidising agent to facilitate removal of tough food stains and other organic stains by chemical oxidation. The oxidising agent may, for example oxidize polyphenolic compounds commonly found in coffee, tea, wine, and fruit stains. Oxidation by the oxidising agent may also aid in bleaching, whitening, and disinfecting fabrics, and may also provide additional washing machine cleanliness and odour prevention. Suitable oxidising agents for use in the invention include peroxy bleach compounds such as sodium perborate monohydrate and tetrahydrate, and sodium percarbonate.
When included, a composition of the invention will preferably comprise from 5 to 35%, preferably from 8 to 20% (by weight based on the total weight of the composition) of one or more oxidising agents such as the peroxy bleach compounds which are described above.
A bleaching activator such as N,N,N',N'-tetraacetylethylenediamine (TAED) or sodium nonanoyloxybenzenesulfonate (NOBS) may be included in conjunction with the one or more oxidising agents to improve bleaching action at low wash temperatures.
A bleaching catalyst may also be included in addition to or instead of a bleach activator. Typical bleaching catalysts include complexes of heavy metal ions such as cobalt, copper, iron, manganese or combinations thereof; with organic ligands such as 1,4,7-triazacyclononane (TACN), 1,4,7-trimethyl-1,4,7-triazacyclononane (Me3
-TACN), 1,5,9-trimethyl-1,5,9-triazacyclononane, 1,5,9-triazacyclododecane, 1,4,7-triazacycloundecane, tris[2-(salicylideneamino)ethyl]amine or combinations thereof.
A composition of the invention may also contain one or more chelating agents for transition metal ions. Such chelating agents may also have calcium and magnesium chelation capacity, but preferentially bind heavy metal ions such as iron, manganese and copper. Such chelating agents may help to improve the stability of the composition and protect for example against transition metal catalyzed 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). Mixtures of any of the above described materials may also be used.
A composition of the invention may also comprise an effective amount of one or more enzyme 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 composition of the invention may contain further optional ingredients to enhance performance and/or consumer acceptability. Examples of such ingredients include dye transfer inhibitors (e.g. polyvinylpyrrolidone), foam control agents, preservatives (e.g. bactericides), anti-shrinking agents, anti-wrinkle agents, antioxidants, sunscreens, anticorrosion agents, drape imparting agents, anti-static agents, ironing aids, colorants, fluorescers, 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 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 laundering fabric using a composition of the invention will usually involve diluting the dose of detergent composition with water to obtain a wash liquor, and washing fabrics with the wash liquor so formed. In automatic washing machines the dose of detergent composition 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. From 5 up to about 65 litres of water may be used to form the wash liquor depending on the machine configuration. The dose of detergent composition may be adjusted accordingly to give appropriate wash liquor concentrations.
The dilution step preferably provides a wash liquor which comprises inter alia
from about 3 to about 20 g/wash of detersive surfactants (as are further defined above). The wash liquor preferably has a pH of from above 7 to less than 13, preferably from above 7 to less than 10.5.
A subsequent aqueous rinse step and drying the laundry is preferred.
The invention will now be further described with reference to the following non-limiting Examples.
Detergent compositions were prepared by adding encapsulated fragrance and free fragrance in varying ratios to a base powder (UK Persil™ Non-Bio powdered laundry detergent).
The absolute and relative levels of free fragrance (f1) and encapsulated fragrance (f2) respectively in each of the formulations is shown below in Table 1.
Examples 1 to 4 represent formulations according to the invention. Examples A to E represent comparative examples (not according to the invention).
All weight percentages are by weight based on total weight of the formulation, unless otherwise specified.
|Example||Level of f1||Level of f2||Total level of (f1+f2)||Weight ratio f1: f2|
Each of the above formulations were evaluated for fragrance performance by trained expert sensory panellists.
Firstly, the fragrance intensity was assessed for each test formulation per se
(i.e. prior to use). Each test formulation was then used to machine wash 2kg loads of test fabric (50:50 cotton / polyester split) using a 30°C cotton short wash programme. Fragrance intensity of the washed test fabric was assessed at the damp stage (1 hour after removal from the washing machine) and at the dry stage (24 hours after removal from the washing machine).
The results are shown below in Table 2.
|Example||Fragrance intensity (formulation per se)||Fragrance intensity (damp test fabric)||Fragrance intensity (dry test fabric)|
These results show that Example A, containing mostly free fragrance, has little effect on the fragrance intensity of the dry test fabric. However, the Example 4 formulation (according to the invention) provides a comparable fragrance intensity to Example A for the formulation per se
and on the damp test fabric, and a significantly better result on the dry test fabric, despite containing a significantly lower level of total fragrance than Example A.
Example B contains a similar amount of total fragrance as Example 1 (according to the invention), but the Example 1 formulation performs significantly better on the damp test fabric.
Example D contains a similar amount of total fragrance as Example 4 (according to the invention). The two formulations gave comparable results in the tests on the formulation per se
and on the damp test fabric but the Example 4 formulation performs significantly better on the dry test fabric.
These results show the enhanced balance of sensory effect overall from the inventive formulations (Examples 1 to 4) when assessed for the three stages of: (i) formulation prior to use; (ii) damp laundry after a wash process and (iii) dry laundry. This enhanced balance is observed even at a reduced total perfume level.