EP4532657A1 - Use of microcapsules in a laundry composition to improve the softness of a fabric - Google Patents

Abstract

Use of a composition comprising microcapsules to improve the softness of a fabric, wherein the microcapsules comprise: a microcapsule wall comprising a bio polymer; and polyisocyanate crosslinking agent.

Description

LAUNDRY COMPOSITION

Field of the Invention

The present invention is in the field of laundry compositions, in particular laundry compositions for improving the softness of a fabric. of the Invention

The softness of a fabric is an important attribute for consumers. Various ingredients have been added to laundry products to improve the softness of laundered fabrics. However, the addition of ingredients to a laundry composition has the drawback of increased complexity in formulation, increased cost and ingredients which may not meet the environmental credentials desired by the consumers.

Microcapsules are used in various laundry applications, to deliver active materials to fabrics. Microcapsules are known to provide various benefits, such as delayed release of protection of the active material against other ingredients in the laundry composition. Conventional microcapsules typically have a microcapsule wall formed of a synthetic polymer such as a melamine formaldehyde polymer or polyacrylate.

Summary of the Invention

It has been found that the use of a microcapsules comprising protein or polysaccharides leads to improved softening of fabrics.

Accordingly in a first aspect of the present invention is provided a use of microcapsules in a laundry composition to improve the softness of a fabric, wherein the microcapsules comprise: a) a microcapsule wall comprising a bio polymer; and b) polyisocyanate crosslinking agent. Detailed of the Invention

These and other aspects, features and advantages will become apparent to those of ordinary skill in the art from a reading of the following detailed description and the appended claims. For the avoidance of doubt, any feature of one aspect of the present invention may be utilised in any other aspect of the invention. The word “comprising” is intended to mean “including” but not necessarily “consisting of” or “composed of.” In other words, the listed steps or options need not be exhaustive. It is noted that the examples given in the description below are intended to clarify the invention and are not intended to limit the invention to those examples per se.

Similarly, all percentages are weight/weight percentages unless otherwise indicated. Except in the operating and comparative examples, or where otherwise explicitly indicated, all numbers in this description indicating amounts of material or conditions of reaction, physical properties of materials and/or use are to be understood as modified by the word “about”. Numerical ranges expressed in the format "from x to y" are understood to include x and y. When for a specific feature multiple preferred ranges are described in the format "from x to y", it is understood that all ranges combining the different endpoints are also contemplated.

By laundry composition it is herein understood to mean a consumer product suitable for use in a laundry process. Examples of such compositions include liquid laundry detergents, laundry detergent powders, fabric conditioners, ancillary laundry compositions such as scent boosters and fabric spray compositions.

By microcapsule composition it is herein understood to mean the composition comprising microcapsules which is added to a laundry composition. The microcapsule composition may comprise only microcapsules or may be in the form of a slurry comprising microcapsules.

By microcapsule it is herein understood to mean the microcapsule (wall and core) i.e. , without a solvent or slurry.

The laundry products of the present invention comprise microcapsules. The microcapsules may simply be provided as microcapsules but preferably are provided in a microcapsule composition comprising microcapsules in a slurry. The microcapsules comprise a microcapsule core comprising an active ingredient and microcapsule wall encapsulating the core. The microcapsule wall comprises a wall polymer and a crosslinking agent. Typically, the microcapsules comprise 10 wt.% to 98 wt.% core materials, 1 wt.% to 20 wt.% wall polymer and optionally 0.2 wt.% to 6 wt.% crosslinking agent. The microcapsules may be prepared by any suitable process including those exemplary processes described here.

Microcapsule wall materials

The microcapsule wall may also be referred to as the microcapsule shell. The microcapsule wall comprises a bio polymer. Bio polymers are natural polymers produced by the cells of living organisms and the derivatives of natural polymers, i.e. polymers derived from bio polymers. Non-limiting examples of suitable bio polymers include: lignin, polysaccharides, proteins and nucleic acids. The microcapsule wall preferably comprises proteins, polysaccharides and mixtures thereof. The biopolymer may be treated by various processes to provide derivatives, including but not limited to hydrolysis, condensation, functionalising such as ethoxylating, crosslinking, etc. Without wishing to be bound by theory, it is believed that the use of proteins or polysaccharides improves the ‘hand’ of a fabric when treated with compositions comprising the microcapsules described herein. The microcapsule wall materials are preferably in an aqueous solution. The microcapsule wall preferably comprises 20 wt.% to 98 wt.% protein, polysaccharide or combinations thereof, more preferably 30 wt.% to 95 wt.%, more preferably 35 wt.% to 95 wt.%, and most preferably 65 wt.% to 90 wt.% by weight of the microcapsule wall.

As is conventional in the art, a “polypeptide” or “protein” is a linear organic polymer composed of amino acid residues bonded together in a chain, forming part of (or the whole of) a protein molecule. “Polypeptide” or “protein” as used herein means a natural polypeptide, polypeptide derivative, and/or modified polypeptide. The polypeptide may exhibit an average molecular weight of from 1 ,000 Da to 40,000,000 Da, preferably greater than 10,000 Da, more preferably, 100,000 Da, most preferably greater than 1,000,000 Da and preferably less than 3,000,000 Da.

Suitable proteins for use in this invention include whey proteins, plant proteins and gelatine. Preferably the plant proteins are used. Suitable preferred proteins include proteins selected from: pea, potato proteins, brown rice, white rice, wheat, egg, barley, pumpkin seed, oat, almond, whey, casein, silk, gelatin, algae, rye, spelt, gluten, rapeseed, sunflower, corn, soybean, bean, chickpea, lentil, lupin, peanut, alfalfa, hemp, proteins resulting from fermentation, proteins from food waste and combinations thereof. Particularly preferred proteins include proteins selected from chickpea, pea proteins, potato proteins, brown rice proteins, white rice proteins, wheat proteins, barley proteins, pumpkin seed proteins, oat proteins, almond proteins, and combinations thereof. This includes derivatives of the aforementioned proteins. As used herein, whey protein refers to the protein contained in whey, a dairy liquid obtained as a supernatant of curds when milk or a dairy liquid containing milk components, is processed into cheese curd to obtain a cheese-making curd as a semisolid. Whey protein is generally understood in principle to include the globular proteins b-lactoglobulin and a-lactalbumin at various ratios such as 1: 1 to 5: 1 (e.g., 2: 1). It may also include lower amounts of serum albumin, immunoglobulin and other globulins. The term whey protein is also intended to include partially or completely modified or denatured whey proteins. Purified b-lactoglobulin and/or a- lactalbumin polypeptides may also be used in preparation of microcapsules of this invention.

Gelatin refers to a mixture of proteins produced by partial hydrolysis of collagen extracted from the skin, bones, and connective tissues of animals. Gelatin can be derived from any type of collagen, such as collagen type I, II, III, or IV. Such proteins are characterized by including Gly- Xaa-Yaa triplets wherein Gly is the amino acid glycine and Xaa and Yaa can be the same or different and can be any known amino acid. At least 40% of the amino acids are preferably present in the form of consecutive Gly-Xaa-Yaa triplets.

A preferred class of proteins are plant proteins. Plant proteins are proteins that accumulate in various plant tissues. Preferred plant proteins can be classified into two classes: seed or grain proteins and vegetable proteins. Seed/grain proteins are a set of proteins that accumulate to high levels in seeds/grains during the late stages of seed/grain development, whereas vegetable proteins are proteins that accumulate in vegetative tissues such as leaves, stems and, depending on plant species, tubers.

Preferred examples of seed/grain/legumes storage proteins are proteins from: soya, lupine, pea, chickpea, alfalfa, horse bean, lentil, and haricot bean; from oilseed plants such as colza, cottonseed and sunflower; from cereals like wheat, maize, barley, malt, oats, rye and rice (e.g., brown rice protein), or a combination thereof.

Preferred examples of vegetable protein are proteins form: potato or sweet potato tubers.

The term plant protein is intended to include a plant protein isolate, plant protein concentrate, or a combination thereof. Plant protein isolates and concentrates are generally understood to be composed of several proteins. For example, pea protein isolates and concentrates may include legumin, vicilin and convicilin proteins. Similarly, brown rice protein isolates may include albumin, globulin and glutelin proteins. The term “plant protein” is also intended to include a partially or completely modified or denatured plant storage protein. Individual polypeptides (e.g., legumin, vicilin, convicilin, albumin, globulin or glutelin) may also be used in preparation of microcapsules of this invention.

A native protein maybe preferred. However, the process may include a step of denaturing the protein by pH adjustment, heat, or adding a chaotropic agent to the oil-in-water emulsion or to the protein before adding to the oil-in-water emulsion.

Denaturation is a process in which proteins (polypeptides) lose the quaternary structure, tertiary structure, and secondary structure present in their native state, by application of a denaturation condition. During denaturation, proteins change their conformational structure by unfolding, thereby making amine and hydroxyl groups available for crosslinking (such as crosslinking with polyisocyanate) to form a microcapsule wall. Exemplary conditions for protein denaturation include, but are not limited to, radiation, exposure to heat or cold, changes in pH with an acid or base, exposure to denaturing agents such as detergents, inorganic salt, organic solvent (e.g., alcohol, ethyl acetate, and chloroform), urea, or other chaotropic agents, or mechanical stress including shear. Exemplary chaotropic agents are guanidine salts (e.g., guanidine hydrochloride and guanidine carbonate), urea, polysorbate, sodium benzoate, vanillin, o-cresol, phenol, propanol, formamide, ethanol, fructose, ammonium sulfate, ammonium chloride, ammonium nitrate, ammonium phosphate, potassium sulfate, potassium chloride, potassium iodide, potassium nitrate, potassium phosphate, sodium sulfate, sodium chloride, sodium bromide, sodium nitrate, sodium phosphate, guanidine thiocyanate, xylose, glycerol, benzyl alcohol, ethyl acetate, triton X-100, ethyl acetate, cetyltrimethylammonium halide, acetone, sodium dodecyl sulfate (SDS), hydrochloric acid, sulfuric acid, polyethylene glycol, glutaraldehyde, and combinations thereof. Any amount of the chaotropic agent can be used.

It may be preferred that the protein is denatured with a chaotropic agent so that 20 wt. % to 100 wt.% preferably 40 wt. % to 100 wt. %, more preferably 60 wt.% to 100 wt.%, most preferably 90 wt.% to 100 wt.% of the protein used in the preparation of the microcapsules is denatured.

The protein used in the microcapsule can also be derivatized or modified (e.g., derivatized or chemically modified). For example, the protein can be modified by covalently attaching sugars, lipids, cofactors, peptides, or other chemical groups including phosphate, acetate, methyl, and other natural or unnatural molecule.

Polysaccharides are a class of carbohydrates comprising multiple monosaccharide units.

“Polysaccharide” as used herein means a natural polysaccharide, polysaccharide derivative, and/or modified polysacharide. Suitable polysaccharides maybe selected from the group consisting of fibres, starch, sugar alcohols, sugars and mixtures thereof.

Examples of suitable fibres include: particular cellulose, cellulose derivatives such as hydroxyethyl cellulose, in particular quaternized hydroxyethyl cellulose, carboxymethylcellulose (CMC) and microcrystalline cellulose (MCC), hemicelluloses, lichenin, chitin, chitosan, lignin, xanthan, plant fibers, in particular cereal fibers, potato fibers, apple fibers, citrus fibers, bamboo fibers, extracted sugar beet fibers; oat fibers and soluble dietary fibers, in particular inulin, especially native inulin, highly soluble inulin, granulated inulin, high performance inulin, pectins, alginates, agar, carrageenan, gum arabic (Senegal type, Seyal type), konjac gum, gellan gum, curdlan (paramylon), guar gum, locust bean gum, xanthan gum, raffinose, xylose, polydextrose and lactulose and combinations thereof. This includes derivatives of the aforementioned polysaccharides.

Examples of suitable starches include starch from: wheat, potatoes, corn, rice, tapioca and oats, modified starch, and starch derivatives, e.g., dextrins or maltodextrins, in particular dextrins and maltodextrins from wheat, potatoes, corn, rice, pea, chickpea and oats, oligosaccharides, in particular oligofructose. Preferred starches are selected from: corn starch, potato starch, rye starch, wheat starch, barley starch, oat starch, rice starch, pea starch, chickpea starch, tapioca starch, and mixtures thereof.

Examples of suitable sugar alcohols include: sorbitol, mannitol, isomalt, maltitol, maltilol syrup, lactitol, xylitol, erythritol.

An example of suitable sugar includes: glucose.

Particularly preferred polysaccharides include: gum Arabic, dextrins and maltodextrins are particularly preferred.

The polysaccharide used in the microcapsule can also be derivatized or modified (e.g., derivatized or chemically modified). For example, the protein can be modified by covalently attaching sugars, lipids, cofactors, peptides, or other chemical groups including phosphate, acetate, methyl, and other natural or unnatural molecule. Examples of suitable polysaccharide derivatives include: starch glycolate, carboxymethyl starch, hydroxyalkyl cellulose and crosslinked modified cellulose.

The microcapsules as described herein may optionally comprise additional polymers in the microcapsule walls. Such additional polymers may include: a sol-gel polymer (e.g., silica), polyacrylate, polyacrylamide, poly(acrylate-co-acrylamide), polyurea, polyurethane, starch, gelatin and gum Arabic, poly(melamine-formaldehyde), poly(urea-formaldehyde), and combinations thereof. However preferably the microcapsule wall polymers consist essentially for proteins, polysaccharides, or combinations thereof.

The microcapsule preferably comprises from 0.1 wt.% to 30 wt.% microcapsule wall, preferably 0.5 wt.% to 25 wt.%, more preferably 1 wt.% to 20 wt.% and 2 wt.% to 15 wt.% microcapsule wall by weight of the microcapsule.

The microcapsule wall polymers described herein are crosslinked. The microcapsules comprise polyisocyanate cross-linking agents. The polyisocyanate cross linking agent is preferably present at a level of 0.1 wt.% to 10 wt.% by weight of the microcapsule more preferably 0.5 wt.% to 9 wt.% by weight of the microcapsule, even more preferably 1 to 8 wt.% by weight of the microcapsule.

Without wishing to be bound by theory, the selection of an isocyanate cross linking agent improves the softening of a fabric treated with a composition comprising the microcapsules.

Polyisocyanates each have at least two isocyanate (-NCO) groups reactive towards proteins or polysaccharides. The polyisocyanate can be aromatic, aliphatic, linear, branched, or cyclic, preferably the polyisocyanate comprises polyisocyanates selected from aliphatic, cycloaliphatic, hydroaromatic, aromatic or heterocyclic polyisocyanate, their substitution products and mixtures thereof, most preferably selected from aromatic, aliphatic polyisocyanate and combinations thereof. It is particularly preferred, that more than one polyisocyanate is present. The isocyanate may be, water soluble or water dispersible, alternatively, it can be soluble in an organic solvent or fragrance oil. Preferably, the polyisocyanate is water insoluble. Preferably, the polyisocyanate comprises, 2 to 4 isocyanate groups. More preferably, the polyisocyanate comprises 3 to 4 isocyanate functional groups.

Examples of suitable polyisocyanate include a trimer of hexamethylene diisocyanate, a trimer of isophorone diisocyanate, a biuret of hexamethylene diisocyanate, a polyisocyanurate of toluene diisocyanate, a trimethylol propane-adduct of toluene diisocyanate, a trimethylol propane - adduct of xylylene diisocyanate, and combinations thereof.

Preferably the polyisocyanate used in this invention is an aromatic poly isocyanate. Preferably, the aromatic polyisocyanate includes a phenyl, tolyl, xylyl, naphthyl or diphenyl moiety as the aromatic component. Particularly preferably, the aromatic polyisocyanate is a polyisocyanurate of toluene diisocyanate, a trimethylol propane -adduct of toluene diisocyanate or a trimethylol propane -adduct of xylylene diisocyanate.

One class of suitable aromatic polyisocyanates are those having the generic structure shown below, and its structural isomers wherein n can vary from zero to a desired number (e.g., 0-50, 0-20, 0-10, and 0-6) depending on the type of crosslinker used. Preferably, the number of n is limited to less than 6. The starting polyisocyanate may also be a mixture of polyisocyanates where the value of n can vary from 0 to 6. In the case where the starting polyisocyanate is a mixture of various polyisocyanates, the average value of n preferably falls in between 0.5 and 1.5.

Commercially-available polyisocyanates include products under the trade names of LUPRANATE® M20 (chemical name: polymeric methylene diphenyl diisocyanate, i.e.,“PMDI”; commercially available from BASF containing isocyanate group “NCO” 31.5 wt%), where the average n is 0.7; PAPI™ 27 (PMDI commercially available from Dow Chemical having an average molecular weight of 340 and containing NCO 31.4 wt%) where the average n is 0.7; MON DUR® MR (PMDI containing NCO at 31 wt% or greater, commerciallyavailable from Covestro, Pittsburg, Pennsylvania) where the average n is 0.8; MONDUR® MR Light (PMDI containing NCO 31.8 wt%, commercially available from Covestro) where the average n is 0.8; MONDUR® 489 (PMDI commercially available from Covestro containing NCO 30-31.4 wt%) where the average n is 1; poly[(phenylisocyanate)-co-formaldehyde] (Aldrich Chemical, Milwaukee, Wl), other isocyanate monomers such as DESMODUR® N3200 (poly(hexamethylene diisocyanate) commercially available from Covestro), and Takenate™ D-l 10N (trimethylol propane -adduct of xylylene diisocyanate, Mitsui Chemicals America, Inc., Rye Brook, NY, containing NCO 11.5 wt%), DESMODUR® L75 (a polyisocyanate base on toluene diisocyanate commercially available from Covestro), and DESMODUR® IL (another polyisocyanate based on toluene diisocyanate commercially available from Covestro). An alternate suitable class of polyisocinates are diisocyanates with the general structure O=C=N-R-N=C=O, wherein R represents aliphatic, alicyclic or aromatic radicals, are used. Preferably, the radicals have five or more carbon atoms.

Other examples of the aromatic polyisocyanate include 1,5-naphthylene diisocyanate, 4,4'- diphenylmethane diisocyanate (MDI), hydrogenated MDI, xylylene diisocyanate (XDI), tetramethylxylol diisocyanate, 4,4'-diphenyldimethylmethane diisocyanate, di- and tetraalkyldiphenylmethane diisocyanate, 4,4'-dibenzyl diisocyanate, 1,3-phenylene diisocyanate, 1,4- phenylene diisocyanate, the isomers of tolylene diisocyanate (TDI), 4,4'-diisocyanatophenyl- perfluoroethane, phthalic acid bisisocyanatoethyl ester, also polyisocyanates with reactive halogen atoms, such as 1 -chloromethylphenyl 2,4-diisocyanate, 1 -bromomethyl -phenyl 2,6- diisocyanate, and 3,3-bischloromethyl ether 4,4'-diphenyldiisocyanate, and combinations thereof.

The weight average molecular weight of useful polyisocyanates is preferably from 200 Da to 2500 Da, more preferably 250 Da to 1000 Da and most preferably from 275 Da to 500 Da.

The polyisocyanate is preferably present in the wall in an amount of 0.1 wt.% to 40 wt.%, more preferably 0.2 wt.% to 25 wt.%, even more preferably 0.25 wt.% to 15 wt.%, and most preferably 0.5 wt.% to 5 wt.%, by weight of the microcapsule wall. Preferably the ratio of polysaccharide and/or protein to polyisocyanate is 1 : 1 to 10: 1.

During the process of preparing the microcapsule composition of this invention, polyisocyanate can be added to the aqueous phase, the oil phase, or the oil-in-water emulsion.

More suitable polyisocyanate examples can be found in WO 2004/054362 and WO 2017/192648.

The microcapsule may optionally comprise further crosslinking agents. The further crosslinking agent maybe selected from the group consisting of transglutaminase, peroxidase, secondary plant substances selected from the group consisting of polyphenols, in particular tannin, gallic acid, ferulic acid, hesperidin, cinnamaldehyde, vanillin, carvacrol, and mixtures of two or more of the aforementioned crosslinking agents. Microcapsule core materials

The core may also be referred to as the internal phase. The core of the microcapsule comprises active material and optionally further comprises solvents, crosslinking agents as described above, or combinations thereof. The core is preferably non-aqueous.

The internal non-aqueous phase may preferably comprise from 20 to 80 wt. %, preferably from 25 to 75 wt.% and even more preferably from 33 to 50 wt.% active material to be encapsulated and preferably from 0.1 to 5 wt.%, preferably from 0.15 to 3.5 wt.% and even more preferably from 0.5 to 2.5 wt.% crosslinking agent and the remaining composition solvent.

Exemplary active materials include: fragrance; malodour agents for example: uncomplexed cyclodextrin, odor blockers, reactive aldehydes, flavonoids, zeolites, activated carbon, and mixtures thereof; dye transfer inhibitors; shading dyes; silicone oils, resins, and modifications thereof such as linear and cyclic polydimethylsiloxanes, amino-modified, allcyl, aryl, and alkylaryl silicone oils, which preferably have a viscosity of greater than 50,000 cst; insect repellents; organic sunscreen actives, for example, octylmethoxy cinnamate; antimicrobial agents, for example, 2-hydroxy-4, 2,4- trichlorodiphenylether; ester solvents, for example isopropyl myristate; lipids and lipid like substance, for example, cholesterol; hydrocarbons such as paraffins, petrolatum, and mineral oil; fish and vegetable oils; hydrophobic plant extracts; waxes; pigments including inorganic compounds with hydrophobically- modified surface and/ or dispersed in an oil or a hydrophobic liquid; sugar-esters, such as sucrose polyester (SPE); and combinations thereof.

The benefit agents may be dissolved in a solvent. Examples of suitable solvents include vegetable oils, glycerides, esters of fatty acids and branched alcohols, hydrocarbon, etc. specific examples include: diethyl phthalate, isopropyl myristate, Abalyn® (rosin resins, available from Eastman), benzyl benzoate, ethyl citrate, limonene or other terpenes, triacetin or isoparaffins, preferably Abalyn®, benzyl benzoate, limonene or other terpenes, isoparaffins, or combinations thereof. Preferably, if present, the solvent is 0 to 30 wt.% of the active material, more preferably 0 to 20 wt.% and most preferably 0 to 10 wt.% of the active material.

Most preferably the active material comprises fragrance. Perfume components are well known in the art. Useful perfume components may include materials of both natural and synthetic origin. They include single compounds and mixtures. Specific examples of such components may be found in the current literature, e.g., in Fenaroli's Handbook of Flavor Ingredients, 1975, CRC Press; Synthetic Food Adjuncts, 1947 by M. B. Jacobs, edited by Van Nostrand; or Perfume and Flavor Chemicals by S. Arctander 1969, Montclair, N.J. (USA). These substances are well known to the person skilled in the art of perfuming, flavouring, and/or aromatizing consumer products.

Particularly preferred perfume components are blooming perfume components and substantive perfume components. Blooming perfume components are defined by a boiling point less than 250°C and a LogP greater than 2.5. Preferably encapsulated perfume compositions comprise at least 20 wt.% blooming perfume ingredients, more preferably at least 30 wt.% and most preferably at least 40 wt.% blooming perfume ingredients. Substantive perfume components are defined by a boiling point greater than 250°C and a LogP greater than 2.5. Preferably encapsulated perfume compositions comprises at least 10 wt.% substantive perfume ingredients, more preferably at least 20 wt.% and most preferably at least 30 wt.% substantive perfume ingredients. Boiling point is measured at standard pressure (760 mm Hg). Preferably a perfume composition will comprise a mixture of blooming and substantive perfume components. The perfume composition may comprise other perfume components.

It is commonplace for a plurality of perfume components to be present in a microcapsule. In the compositions for use in the present invention it is envisaged that there will be three or more, preferably four or more, more preferably five or more, most preferably six or more different perfume components in a microcapsule. An upper limit of 300 perfume components may be applied.

Preferably the amount of encapsulated active material is from 5 wt.% to 95 wt.%, preferably 10 wt.% to 90 wt.% more preferably 15 wt.% to 85 wt.%, and most 20 wt.% to 80 wt.% by weight of the microcapsule.

Additional microcapsule ingredients

The microcapsule composition may comprise further ingredients. A preferred further ingredient are polyphenols. Particularly preferred are phenols having a 3,4,5-trihydroxyphenyl group or 3,4-dihydroxypheny group such as tannic acid. In additional to polyphenols, other polyols can also be used to prepare the microcapsule compositions of this invention. Examples include pentaerythritol, dipentaerythritol, glycerol, polyglycerol, ethylene glycol, polyethylene glycol, trimethylolpropane, neopentyl glycol, sorbitol, erythritol, threitol, arabitol, xylitol, ribitol, mannitol, galactitol, fucitol, iditol, inositol, volemitol, isomalt, maltitol, lactitol, maltotriitol, maltotetraitol, polyglycitol, polyphenol, and combinations thereof. Polyphenols, polyols, and multi-functional aldehydes are preferably present at a level of 0 wt.% to 40 wt.%, preferably 1 wt.% to 35 wt.% more preferably 5 wt.% to 35 wt.% and most preferably 10 wt.% to 30 wt.%.

Microcapsule composition

The microcapsules described herein preferably have a diameter of 0.1 microns to 1000 microns, more preferably 0.5 microns to 500 microns, even more preferably 1 micron to 200 microns, and most preferably 1 micron to 100 microns.

The microcapsules can be positively or negatively charged with a zeta potential of preferably - 200 mV to +200 mV, more preferably 25 mV to 200 mV, and most preferably 40 mV to 100 mV. Preferably, the microcapsules are positively charged. Zeta potential is a measurement of electrokinetic potential in the microcapsule. From a theoretical viewpoint, zeta potential is the potential difference between the water phase (/. e. , the dispersion medium) and the stationary layer of water attached to the surface of the microcapsule. The zeta potential can be calculated using theoretical models and an experimentally-determined electrophoretic mobility or dynamic electrophoretic mobility. The zeta potential is conventionally measured by methods such as microelectrophoresis, or electrophoretic light scattering, or electroacoustic phenomena. For more detailed discussion on measurement of zeta potential, see Dukhin and Goetz, "Ultrasound for characterizing colloids", Elsevier, 2002.

The microcapsule composition of this invention can be a slurry containing a solvent, preferably water. The microcapsules are preferably present in the slurry as 0.1 wt.% to 80 wt.%, more preferably 1 wt.% to 65 wt.% and most preferably 5 wt.% to 45 wt.% by weight of the microcapsule composition. The slurry may comprise a thickening or suspending agent such as xanthan gum, carboxymethyl cellulose (CMC), microcrystalline cellulose (MCC) or guar gum.

Alternatively, the microcapsule composition of this invention can also be dried, e.g., spray dried, heat dried, and belt dried, to a solid form.

The microcapsule composition maybe purified by washing the capsule slurry with water until a neutral pH (pH of 6 to 8) is achieved. For the purposes of the present invention, the capsule suspension can be washed using any conventional method including the use of a separatory funnel, filter paper, centrifugation and the like. The capsule suspension can be washed one, two, three, four, five, six, or more times until a neutral pH, e.g., pH 6-8 and 6.5-7.5, is achieved. The pH of the purified capsules can be determined using any conventional method including, but not limited to pH paper, pH indicators, or a pH meter. In certain embodiments of this invention, the purification of the capsules includes the additional step of adding a salt to the capsule suspension prior to the step of washing the capsule suspension with water. Exemplary salts of use in this step of the invention include, but are not limited to, sodium chloride, potassium chloride or bi-sulphite salts. See US 2014/0017287.

Preparation of the microcapsules

When preparing the microcapsule, the polymers may be provided in a solvent. Suitable solvents for preparing the microcapsule wall include water or mixtures of water with at least one water- miscible organic solvent. Suitable organic solvents include glycerol, 1 ,2-propanediol, 1 ,3- propanediol, ethanediol, diethylene glycol, triethylene glycol, and other analogues. Preferably the solvent is water.

A stabiliser may also be present. A stabiliser maybe be selected from acrylic co-polymers, preferably with sulphonate groups, copolymers of acrylamides and acrylic acid, copolymers of alkyl acrylates and N-vinylpyrrolidone, such as LUVISKOL® K15, K30 or K90 (BASF); sodium polycarboxylates, sodium polystyrene sulfonates, vinyl and methyl vinyl ether-maleic acid anhydride copolymers as well as ethylene, isobutylene or styrene-maleic acid anhydride copolymers, microcrystalline cellulose, which is commercially available, for example, under the name VIVAPUR®, diutan gum, xanthan gum or carboxymethyl celluloses.

The crosslinking of the microcapsule preferably involves a catalyst. The catalyst may be present in the microcapsule core active material or added separately to the oil-in-water emulsion or dispersion. A preferred catalyst for the formation of microcapsules according to the present invention is diazabicyclo[2.2.2]octane (DABCO), also known as triethylenediamine (TEDA). Also suitable are catalysts based on bismuth or tin, transglutaminase, peroxidase, secondary plant compounds selected from the group, which consists of polyphenols, in particular tannin, gallic acid, ferulic acid, hesperidin, cinnamaldehyde, vanillin, carvacrol, and mixtures thereof.

Alternatively, or additionally the formation of the microcapsules may be catalyst by heating the oil-in-water emulsion or dispersion. For example, heating to a temperature range of a temperature in the range of 60 °C to 90 °C.

Various suitable methods of production may be implemented to produce the microcapsules suitable for use in the present invention. One suitable method if interfacial polymerization. An examples of interfacial polymerization involves the steps of:

(i) Providing the microcapsule core materials including at least one first crosslinking agent, wherein the crosslinking agent is substantially dissolved together with the core materials, this is the oil phase. A non-aqueous solvent many optionally be present;

(ii) Providing the microcapsule wall materials comprising at least one protein, at least one polysaccharide, or combinations thereof. This is the aqueous phase. An aqueous solvent many optionally be present;

(iii) Emulsifying or dispersing the microcapsule core materials with the microcapsule wall materials. Preferably in a ratio of from 70 : 30 to 60 : 40, preferably in a range from 30 : 70 to 60 : 40. Optionally an emulsifier may be used. Emulsification may be achieved by use of high-speed mixing. After completion of this stage, an oil-in-water emulsion or dispersion is present in which the internal phase with the active materials to be encapsulated is finely emulsified or dispersed in the external wall material phase in the form of droplets;

(iv) First crosslinking optionally by the addition of at least one catalyst to obtain a microcapsule slurry, optionally with the addition of further protein, polysaccharide polymers, or combination thereof;

(v) Curing the microcapsule slurry, preferably at a temperature of at least 60 °, preferably for at least 30 minutes, followed by cooling;

(vi) Optionally drying, using methods such as spray drying, filtration, or freeze drying.

An alternative method involves 3D printing the microcapsules. Both the microcapsule shell and microcapsule core can be printed using a printing system. See WO2016172699A1. The printing steps generally include depositing the active materials and the microcapsule shell material in a layer-by-layer fashion, preferably through separate printer heads.

Laundry composition

The laundry compositions of the present invention comprise 0.05 to 20 wt.% microcapsules, by weight of the composition. More preferably 0.075 to 10 wt.% microcapsules, most preferably 0.1 to 6 wt.% microcapsules. The laundry compositions described herein may be any suitable laundry composition. The compositions may be selected from: liquid detergents, powder detergents, fabric conditioners, ancillary compositions such as liquid fragrance boosters or fragrance beads and fabric sprays. Preferably the composition is a fabric conditioner, ancillary composition, or a fabric spray. More preferably the composition is a fabric conditioner.

Liquid and powder detergents are cleaning compositions intended for use in the wash stage of the laundry process. Detergents comprise anionic and or non-ionic surfactants for cleaning fabrics. Preferably liquid detergents comprise at least 3%, preferably from 5 to 60%, and more preferably from 6 to 50% (by weight based on the total weight of the composition) of one or more anionic and/or non-ionic surfactants. Preferred anionic surfactants include: alkylbenzene sulfonates, preferably linear alkylbenzene sulfonates (LAS); alkyl ether, preferably sulfates sodium lauryl ether sulfate (SLES); alkyl sulfate surfactant, preferably primary alkyl sulfanant (PAS). Particularly preferred anionic surfactants are selected from: linear alkyl benezene sulphonates, sodium lauryl ether sulphonates with 1 to 3 moles (average) of ethoxylation, primary alkyl sulphonates, methyl ether sulphates and secondary alkyl sulphonates or mixtures thereof. Preferred non-ionic surfactants are polyoxyalkylene compounds. Particularly preferred non-ionic surfactants are selected from: C8 to C22 alkyl phenol ethoxylates with an average of from 5 to 25 moles of ethylene oxide per mole of alkyl phenol; and C8 to C18 aliphatic alcohol ethoxylates with an average of from 2 to 40 moles of ethylene oxide per mole of alcohol.

Detergents may further comprise: co-surfactants such as amphoteric (zwitterionic) and/or cationic surfactants) in addition to the anionic and/or nonionic surfactants; builders such as hydroxides, carbonates, silicates, zeolites, and mixtures thereof; fatty acids such as aliphatic carboxylic acids; dye transfer inhibitors; anti-redeposition polymers; soil release polymers; transition metal chelating agents; hydrotrope; shading dye; fluorescent agents; enzymes; and combinations thereof.

Fabric conditioners are compositions for use in the rinse stage of the laundry process. Fabric conditioners comprise fabric softening actives. The fabric softening active maybe selected from: quaternary ammonium compounds, silicone polymers, polysaccharides, clays, amines, fatty esters, dispersible polyolefins, polymer latexes and mixtures thereof. Preferably the fabric softening active is a quaternary ammonium compound, preferably an esterlinked quaternary ammonium compound, for example ester-linked triethanolamine (TEA) quaternary ammonium compounds or diethyldialkylester dimethyl ammonium chloride. Fabric conditioners may further comprise: non-ionic surfactants; co-softeners such as fatty esters and fatty alcohols; cationic polymers; rheology modifiers; and combinations thereof.

Ancillary compositions are compositions intended to be used in addition to a detergent or fabric conditioner composition. Ancillary compositions deliver additional benefit agents in the laundry process. Being a separate product, these compositions allow the consumer to tailor the benefit agents to suit the laundry load and their personal preferences. The ancillary laundry compositions may be liquid or solid.

Liquid ancillary laundry compositions comprise a liquid carrier, preferably water and the microcapsules described herein. Liquid ancillary laundry compositions may preferably comprise ingredients such as: non-ionic surfactants, emulsifiers, rheology modifiers, non-encapsulated benefit agents.

Solid ancillary laundry compositions comprise a solid carrier. The carrier material may be selected from the group consisting of: synthetic polymers (e g, polyethylene glycol, ethylene oxide/propylene oxide block copolymers, polyvinyl alcohol, polyvinyl acetate, and derivatives thereof), proteins (e.g., gelatin, albumin, casein), saccharides (e.g. dextrose, fructose, galactose, glucose, isoglucose, sucrose), polysaccharides (e.g., starch, xanthan gum, cellulose, or derivatives thereof), water-soluble or water dispersible fillers (e.g. sodium chloride, sodium sulfate, sodium carbonate/bicarbonate, zeolite, silica, clay), vegetable soap (e.g. coconut soap beads or palm soap), ethoxylated non-ionic surfactants (having a formula RIO(R2O)XH, wherein Ri preferably comprises 12 to 20 carbon atoms, R2 is C2H4 or mixture of C2H4 and C3H6 units and x = 8 to 120), urea and combinations thereof. Preferred carrier materials may be selected from the group consisting of synthetic polymers (e g, polyethylene glycol, ethylene oxide/propylene oxide block copolymers, polyvinyl alcohol, polyvinyl acetate, and derivatives thereof), polysaccharides (e.g., starch, xanthan gum, cellulose, or derivatives thereof), saccharides (e.g, dextrose, fructose, galactose, glucose, isoglucose, sucrose), vegetable soap (e.g. coconut soap beads or palm soap), ethoxylated non-ionic surfactants (having a formula RIO(R2O)XH, wherein R1 preferably comprises 12 to 20 carbon atoms, R2 is C2H4 or mixture of C2H4 and C3H6 units and x = 8 to 120) and combinations thereof. The solid ancillary composition may preferably comprise ingredients such as: non-encapsulated benefit agents and dyes.

Fabric sprays are compositions suitable for spraying onto a fabric. The spray comprises a liquid carrier, preferably water and the microcapsules described herein. The spray composition may preferably comprise ingredients such as: non-ionic surfactants, non-encapsulated benefit agents, lubricants, structuring polymers, anti-malodor ingredients and combinations thereof.

The laundry compositions described herein preferably comprises 0.01 to 20 wt.% perfume microcapsules, more preferably 0.05 to 15 wt. % perfume microcapsules, more preferably 0.1 to 10 wt. % perfume microcapsules more preferably 0.5 to 8 wt. % perfume microcapsules by weight of the laundry composition.

The laundry compositions described herein preferably comprise free perfume in addition to the microcapsules described herein. The compositions preferably comprises 0.1 to 15 wt.% free perfume, more preferably 0.5 to 8 wt. % free perfume.

Particularly preferred perfume components are blooming perfume components and substantive perfume components. Blooming perfume components are defined by a boiling point less than 250°C and a LogP or greater than 2.5. Substantive perfume components are defined by a boiling point greater than 250°C and a LogP greater than 2.5. Boiling point is measured at standard pressure (760 mm Hg). Preferably a perfume composition will comprise a mixture of blooming and substantive perfume components. The perfume composition may comprise other perfume components.

It is commonplace for a plurality of perfume components to be present in a free oil perfume composition. In the compositions for use in the present invention it is envisaged that there will be three or more, preferably four or more, more preferably five or more, most preferably six or more different perfume components. An upper limit of 300 perfume components may be applied.

The laundry compositions may further comprise other ingredients of laundry compositions as will be known to the person skilled in the art. Among such materials there may be mentioned: antifoams, insect repellents, shading or hueing dyes, preservatives (e.g. bactericides), pH buffering agents, hydrotropes, anti-redeposition agents, soil-release agents, polyelectrolytes, anti-shrinking agents, anti-wrinkle agents, anti-oxidants, dyes, colorants, sunscreens, anticorrosion agents, drape imparting agents, anti-static agents, sequestrants, pearlisers, opacifiers and ironing aids. Use of the compositions

The microcapsules in the compositions described herein are used to improve softening. The compositions are applied to a fabric during the laundry process and improved softening is achieved. Softening can be assessed either by a sensory evaluation of using mechanical measurements. An improvement in softening can be measured using a PhabrOmeter® supplied by Nu Cybertek, Inc.

The following microcapsules were used to assess the effects of the compositions described herein:

• Microcapsules A - Pea protein and sodium alginate mix and with salt crosslinking

• Microcapsules 1 -Pea protein and crosslinked with polyisocyanate (Poly[(phenyl isocyanateO-co-formaldehyde])

The same model fragrance composition was used in all microcapsules.

Microcapsule A was prepared as follows: a 10% w/v solution of pea protein was prepared in demineralised water and the pH was adjusted to pH9 using a few drops of sodium carbonate solution. This was heated to 85 °C and mixed at 300RPM mixed on a tornado mixer for 2hrs. After 2hrs the pH was dropped to pH7 with a few drops of 2M HCI solution and 1.5g of sodium alginate was added.

This was further mixed at 300RPM for 90min until homogeneous and then was left overnight to cool down. Once cool the next day 22.5g of fragrance oil was added and mixed at 300RPM for 1 hr. The prepolymer mix was then added into a 80ml solution containing tween 80, calcium chloride and DI water at varying concentrations. The solution was homogenised to produce a suspension. Table 1: Microcapsule A composition

Microcapsule 1 was prepared as follows: an oil phase was first prepared by mixing 23.2g of a model fragrance and 4.8g of caprylic/capric triglyceride, 0.38g of benzyl benzoate and an aromatic polyisocyanate 0.38g. In a separate beaker, an aqueous solution was obtained by mixing 1.182g of a pea protein isolate in 170g of water. The oil phase was then emulsified into the aqueous phase to form an oil-in-water emulsion using an ultra turrax mixer at a shear rate of 5000 Revolutions Per Minute (RPM). The oil-in-water emulsion was then cured at 55°C for 2 hours.

Table 2: Microcapsule 1 composition Preparation of fabric conditioner

Table 3: Fabric conditioner composition

Fabric softening active¹ - Dialkyloxyethyl Hydroxyethyl Methyl Ammonium Methyl sulphate

The fabric conditioner was prepared by melting the fabric softening active at ~65 °C. Water was heated to ~40°C. The minors and fabric softening active were added with stirring. The water was then cooled slightly. The composition was then cooled to room temperature. The perfume microcapsules were then added to the compositions. 2 wt.% is based of weight of microcapsules.

Wash method

The washes took place in a Terg-O-Tometer pot. 0.5 ml of the test fabric conditioner composition and 1 L of water were added to the tergo pot, followed by 40g of knitted cotton. The test monitors were rinsed in the liquor for 10 minutes and spun for 30 seconds. The fabrics were then hung to dry in ambient conditions.

Analysis

The properties of the fabrics were assessed using a Phabrometer by NUCybertek*. A 11 ,3cm disc is cut out from the test fabric. The fabric measurements were performed using a Phabrometer and according to AATCC standard TM202. 10 repeat measurements were taken for each fabric, and the results averaged. Table 4: Results A higher number indicates an improved softening performance. The fabrics treated with a laundry product comprising microcapsules having a polyisocyanate crosslinking agent are softer.

Claims

1. Use of microcapsules in a laundry composition to improve the softness of a fabric, wherein the microcapsules comprise: a) a microcapsule wall comprising a bio polymer; and b) polyisocyanate crosslinking agent.

2. Use according to claim 1, wherein the microcapsules encapsulate fabric benefit agents.

3. Use according to any preceding claim wherein the microcapsules encapsulate perfume.

4. Use according to any preceding claim, wherein the laundry composition comprises 0.05 to 20 wt.% microcapsules.

5. Use according to any preceding claim, wherein the laundry composition is selected from: liquid laundry detergents, powdered laundry detergents, fabric conditioners, ancillary laundry compositions and fabric sprays.

6. Use according to any preceding claim wherein the laundry composition is a fabric conditioner composition.

7. Use according to any preceding claim wherein the biopolymer comprises a polymer selected from proteins, polysaccharides or combinations thereof.

8. Use according to any proceeding claims, wherein the microcapsules comprise 0.1 wt.% to 40 wt.% crosslinking agent by weight of the microcapsule.

9. Use according to any proceeding claims, wherein the polyisocyanate crosslinking agent comprises 2 to 4 isocyanate groups.

10. Use according to any proceeding claims, wherein the polyisocyanate crosslinking agent comprises an aromatic poly isocyanate.

11. Use according to any proceeding claims, wherein the polyisocyanate crosslinking agent has a weight average molecular from 200 Da to 2500 Da.