Treatment composition with delivery particles made from acid-treated chitosan

Abstract

A treatment composition comprising a treatment adjuvant and a population of core / shell delivery particles wherein the shell is made from an acid-treated chitosan and a cross-linking agent wherein the acid-treated chitosan is produced by treating chitosan with a weak acid, or even a mixture of a strong acid and a weak acid. Related methods of making and using such compositions.

Description

Technical Field

[0001] The present disclosure relates to a treatment composition comprising a treatment adjuvant and a population of core / shell delivery particles, wherein the shell is made of acid-treated chitosan and a crosslinking agent, and wherein the acid-treated chitosan is produced by treating chitosan with a weak acid, or even a mixture of a strong acid and a weak acid. The present disclosure also relates to related methods of preparing and using such compositions. Background Art

[0002] Delivery particles, particularly core / shell delivery particles, are a convenient way to deliver beneficial agents in treatment compositions such as laundry products. For environmental reasons, it may be desirable to use delivery particles having a wall made of materials from natural sources and / or biodegradable materials.

[0003] Delivery particles having a shell made at least in part of a chitosan-based material are known. However, such particles may not deliver the desired level of performance. Additionally, chitosan can be a challenging material to work with due to its tendency to increase viscosity.

[0004] U.S. Patent Publication 2020 / 0252469 discloses treating chitosan in an acidic medium by adjusting the pH, for example with hydrochloric acid (HCl), prior to forming microcapsules. However, there are challenges associated with such treatment methods. For example, under certain conditions, hydrochloric acid can be corrosive to manufacturing equipment, which is typically made of steel. Additionally or alternatively, there remains a desire to improve the performance of the delivery particles.

[0005] There is a need for improved treatment compositions and related methods that comprise delivery particles made of chitosan-based materials. Summary of the Invention

[0006] The present disclosure relates to a treatment composition comprising chitosan-based core / shell delivery particles, wherein the chitosan is treated with a weak acid, or even a mixture of a strong acid and a weak acid. For example, the present disclosure relates to a treatment composition comprising a treatment adjuvant and a population of delivery particles, wherein the delivery particles comprise a core and a shell surrounding the core, wherein the core comprises a beneficial agent, wherein the shell comprises a polymeric material that is a reaction product of chitosan and a crosslinking agent, wherein the acid-treated chitosan is produced by treating chitosan with a mixture of a first acid and a second acid, the first acid comprising a strong acid and the second acid comprising a weak acid, wherein the first acid and the second acid are present in an equivalent concentration ratio of from about 20:80 to about 80:20, preferably from 35:65 to about 65:35, and wherein the chitosan is treated with the mixture at a pH of 6.5 or less and at a temperature of at least 25°C.

[0007] The present disclosure also relates to a treatment composition comprising a treatment adjuvant and a population of delivery particles, wherein the delivery particles comprise a core and a shell surrounding the core, wherein the core comprises a beneficial agent, wherein the shell comprises a polymeric material which is a reaction product of an acid-treated chitosan and a crosslinking agent, wherein the acid-treated chitosan is produced by treating chitosan with an acid, wherein the acid comprises one or more weak acids, and wherein the chitosan is treated with the acid at a pH of 6.5 or less and at a temperature of at least 25 °C; and wherein the treatment adjuvant comprises a conditioning active substance.

[0008] The present disclosure also relates to a method of preparing a treatment composition, wherein the method comprises the steps of: providing a base composition, wherein the base composition comprises a treatment adjuvant; and combining the population of delivery particles with the base composition.

[0009] The present disclosure also relates to a method of treating a surface, wherein the method comprises the steps of: contacting a surface, preferably a fabric, with a treatment composition as described herein. Detailed Description

[0010] The present disclosure relates to a treatment composition comprising delivery particles having a shell at least partially made of a chitosan-based material. Specifically, the delivery particles comprise a shell comprising a reaction product of chitosan and a crosslinking agent. Prior to shell formation, the chitosan used to prepare the particle shell is treated with a weak acid or even a mixture of acids (i.e., a mixture comprising strong and weak acids).

[0011] Typically, for example during the preparation of delivery particles, when chitosan is dissolved in water, the resulting mixture tends to be very viscous. This can lead to flowability and processing challenges and / or inhibit the full formation of the delivery particle shell. It has been found that acid treatment can result in a reduction in the viscosity of the mixture. Additionally, it is believed that acid treatment of chitosan can beneficially affect the molecular weight of chitosan, thereby improving shell formation and / or delivery performance.

[0012] That is, even when treating chitosan at a consistent pH, it has been found that the choice of acid can make a difference. For example, using a strong acid such as HCl alone may produce relatively suitable particles but may pose potential corrosion problems in a manufacturing facility.

[0013] Surprisingly, it has been found that treating chitosan with a weak acid or even an acid mixture comprising a weak acid can produce suitable delivery particles while reducing corrosion challenges to manufacturing equipment. Even more surprisingly, it has been found that careful selection of the acid (or rather, acids) can provide benefits in one or more carriers. For example, it is believed that treating chitosan with a mixed acid system comprising a strong acid and a weak acid (especially in a certain ratio) will produce delivery particles with good performance while reducing the corrosion risk in a manufacturing facility.

[0014] The acid-treated chitosan, delivery particles, treatment compositions, and related methods of the present disclosure are discussed in more detail below.

[0015] As used herein, the articles "a" and "an" when used in the claims are understood to mean one or more of the things claimed or described. As used herein, the terms "comprising," "including," and "containing" are intended to be non-limiting. The compositions of the present disclosure may comprise, consist essentially of, or consist of the components of the present disclosure.

[0016] The term "substantially free of" may be used herein. This means that the indicated material is present in very small amounts, not intentionally added to form part of the composition, or preferably the indicated material is not present at levels detectable by analysis. This means compositions that include those in which the indicated material is present only as an impurity in one of the other materials intentionally added. If present at all, the indicated material may be present at levels less than 1%, or less than 0.1%, or less than 0.01%, or even 0% by weight of the composition.

[0017] As used herein, "consumer product" means baby care products, beauty care products, fabric and home care products, household care products, feminine care products, and / or health care products or devices intended to be used or consumed in a sold form and not intended for subsequent commercial manufacture or modification. Such products include, but are not limited to, diapers, bibs, wipes; products and / or methods related to the treatment of human hair, which treatment includes bleaching, coloring, dyeing, conditioning, shampooing, styling; deodorants and antiperspirants; personal cleansing; skin care, including the application of creams, lotions, and other topically applied products for consumer use; and shaving products, products and / or methods related to the treatment of fabrics, hard surfaces, and any other surfaces in the fabric and home care areas, including: air care, automotive care, dishwashing, fabric conditioning (including softening), laundry detergency, laundry washing and rinse additives and / or care, hard surface cleaning and / or treatment, and other cleaning for consumer or business use; products and / or methods related to toilet paper, facial tissue, paper handkerchiefs, and / or paper towels; tampons, feminine sanitary pads; adult incontinence products; products and / or methods related to oral care, including toothpaste, teething gels, tooth cleaning, denture adhesives, teeth whitening; over-the-counter health care products, including cough and cold medicines; pest control products; and water purification.

[0018] As used herein, the phrase "fabric care composition" includes compositions and formulations designed to treat fabrics. Such compositions include, but are not limited to, laundry cleaning compositions and detergents, fabric softening compositions, fabric enhancing compositions, fabric freshening compositions, laundry pre-wash compositions, laundry pre-treatment agents, laundry additives, spray products, dry cleaning agents or compositions, laundry rinse additives, wash additives, post-rinse fabric treatment agents, ironing aids, unit dose formulations, delayed delivery formulations, detergents incorporated in or on a porous substrate or nonwoven sheet, and other suitable forms that would be apparent to one of ordinary skill in the art in light of the teachings herein. Such compositions can be used as laundry pre-treatment agents, laundry post-treatment agents, or can be added during the rinse cycle or wash cycle of a laundry operation.

[0019] As used herein, unless otherwise indicated, the terms "delivery particle", "particle", "encapsulate", "microcapsule", and "capsule" are used interchangeably. As used herein, these terms generally refer to core / shell delivery particles.

[0020] Unless otherwise indicated, all component or composition levels are based on the active portion of that component or composition and do not include impurities, such as residual solvents or by-products, that may be present in commercially available sources of such components or compositions.

[0021] Unless otherwise indicated, all temperatures herein are in degrees Celsius (°C). Unless otherwise indicated, all measurements herein are made at 20 °C and atmospheric pressure.

[0022] In all embodiments of the present disclosure, unless otherwise specifically stated, all percentages are by weight of the total composition. Unless otherwise specifically stated, all ratios are weight ratios.

[0023] It should be understood that every upper numerical limit given throughout this specification includes every lower numerical limit, as if such lower numerical limits were expressly written herein. Every lower numerical limit given throughout this specification will include every upper numerical limit, as if such upper numerical limits were expressly written herein. Every numerical range given throughout this specification will include every narrower numerical range that falls within such broader numerical range, as if such narrower numerical ranges were all expressly written herein.

[0024] Treatment composition

[0025] The present disclosure relates to treatment compositions (or simply "compositions" as used herein). The compositions of the present disclosure can comprise a population of delivery particles and a treatment adjuvant, each described in more detail below. The treatment compositions can be used in the methods of treating surfaces such as fabrics described herein.

[0026] The treatment composition is preferably a consumer product composition. The consumer product compositions of the present disclosure can be used in baby care products, beauty care products, fabric care products, home care products, household care products, feminine care products, and / or healthcare applications. The consumer product composition can be used to treat surfaces such as fabrics, hair, or skin. The consumer product composition is typically intended to be used or consumed in its sold form. The consumer product compositions of the present disclosure are generally not intended for subsequent commercial manufacturing or modification.

[0027] The consumer product composition can preferably be a fabric care composition, a hard surface cleaner composition, a dish care composition, a hair care composition (such as a shampoo or conditioner), a body cleansing composition, or a mixture thereof, preferably a fabric care composition.

[0028] The consumer product composition can be a fabric care composition, such as a laundry detergent composition (including heavy-duty liquid detergents or unit dose products), a fabric conditioning composition (including liquid fabric softening and / or enhancing compositions), a laundry additive, a fabric pretreatment composition (including sprays, pourable liquids, or sprays), a fabric freshener composition (including sprays), or a mixture thereof. The treatment composition is preferably a fabric conditioning composition, even more preferably a liquid fabric conditioning composition.

[0029] The composition can be a beauty care composition, such as a hair treatment product (including shampoos and / or conditioners), a skin care product (including creams, lotions, or other topically applied products for consumer use), a shaving care product (including shaving lotions, foams, or pre- or post-shave treatments), a personal cleansing product (including liquid bath products, liquid hand soaps, and / or bar soaps), a deodorant and / or antiperspirant, or a mixture thereof.

[0030] The composition can be a home care composition, such as air care, automotive care, dishwashing, hard surface cleaning and / or treatment, and other cleaning for consumer or institutional use.

[0031] The treatment composition can be in the form of a liquid composition, a particulate composition, an aqueous colloid, a single-compartment sachet, a multi-compartment sachet, a soluble sheet, a lozenge or bead, a fibrous article, a tablet, a stick, a bar, a wafer, a foam / mousse, a nonwoven sheet, or a mixture thereof.

[0032] The treatment composition can be in liquid form. The liquid composition preferably can contain about 50% to about 97%, preferably about 60% to about 96%, more preferably about 70% to about 95%, or even about 80% to about 95% water, based on the weight of the fabric treatment composition. The liquid composition can be a liquid fabric conditioner. The liquid can be packaged in a pourable bottle. The liquid can be packaged in an aerosol can or other spray bottle. Suitable containers are described in more detail below.

[0033] The treatment composition can be in solid form. The composition can be in the form of beads or tablets, which can be made from a liquid melt. The composition can be an extruded product. The treatment composition can be in the form of a powder or granules.

[0034] The composition can be in the form of a combined dose article such as a tablet, sachet, sheet, or fibrous article. Such sachets typically include a water-soluble film, such as a polyvinyl alcohol water-soluble film, which at least partially encapsulates the composition. Suitable films are available from MonoSol, LLC (Indiana, USA). The composition can be encapsulated in a single-compartment sachet or a multi-compartment sachet. The multi-compartment sachet can have at least two, at least three, or at least four compartments. The multi-compartment sachet can include compartments that are side-by-side and / or stacked. The composition contained in the sachet or its compartments can be liquid, solid (such as a powder), or a combination thereof. The sachet composition can have a relatively small amount of water, for example, less than about 20%, or less than about 15%, or less than about 12%, or less than about 10%, or less than about 8% water, based on the weight of the detergent composition.

[0035] The treatment composition can be in spray form and can be dispensed from a bottle, for example, via a trigger sprayer and / or an aerosol container having a valve.

[0036] The treatment composition can have a viscosity at 20s -1 and 21 °C of from 1 centipoise to 1500 centipoise (1 mPa·s to 1500 mPa·s), from 100 centipoise to 1000 centipoise (100 mPa·s to 1000 mPa·s), or from 200 centipoise to 500 centipoise (200 mPa·s to 500 mPa·s).

[0037] The treatment composition of the present disclosure may be characterized by a pH of from about 2 to about 12, or from about 2 to about 8.5, or from about 2 to about 7, or from about 2 to about 5. The treatment composition of the present disclosure may have a pH of from about 2 to about 4, preferably from about 2 to about 3.7, more preferably from about 2 to about 3.5, and is preferably in the form of an aqueous liquid. It is believed that such pH levels are beneficial for the stability of the quaternary ammonium ester compound (if present). On the other hand, the detergent composition is generally characterized by a pH of from about 7 to about 12, preferably from about 7.5 to about 11. The pH of the composition is measured by dissolving / dispersing the composition in deionized water at about 20 °C to form a 10% strength solution.

[0038] The additional components and / or features of the composition are discussed in more detail below.

[0039] Delivery particle population

[0040] The treatment composition of the present disclosure comprises a population of delivery particles. The delivery particles comprise a core and a shell surrounding the core. The core may comprise a beneficial agent and optionally a partitioning modifier. The core may be liquid or solid at room temperature, preferably liquid.

[0041] The treatment composition may comprise from about 0.05% to about 20%, or from about 0.05% to about 10%, or from about 0.1% to about 5%, or from about 0.2% to about 2% by weight of the composition of the delivery particles. The composition may comprise a sufficient amount of the delivery particles to provide from about 0.05% to about 10%, or from about 0.1% to about 5%, or from about 0.1% to about 2% by weight of the composition of the encapsulated beneficial agent, which may preferably be a fragrance ingredient. When discussing the amount or weight percentage of the delivery particles herein, it means the sum of the wall material and the core material.

[0042] The population of delivery particles according to the present disclosure may be characterized by a volume-weighted median particle size of from about 1 micron to about 100 microns, preferably from about 10 microns to about 100 microns, preferably from about 15 microns to about 50 microns, more preferably from about 20 microns to about 40 microns, and even more preferably from about 25 microns to about 35 microns. For certain compositions, preferably, the population of delivery particles is characterized by a volume-weighted median particle size of from about 1 micron to about 50 microns, preferably from about 5 microns to about 20 microns, and more preferably from about 10 microns to about 15 microns. Different particle sizes can be obtained by controlling the droplet size during the emulsification process.

[0043] The delivery particles may be characterized in that, by weight, the ratio of the core to the shell is up to 99:1, or even 99.5:0.5. The shell may be present at a level of about 1% to about 25%, preferably about 1% to about 20%, preferably about 1% to 15%, more preferably about 5% to about 15%, even more preferably about 10% to about 15%, and even more preferably about 10% to about 12% based on the weight of the delivery particles. The shell may be present at a content of at least 1%, preferably at least 3%, more preferably at least 5% based on the weight of the delivery particles. The shell may be present at a level of up to about 25%, preferably up to about 20%, more preferably up to about 15%, more preferably up to about 12% based on the weight of the delivery particles.

[0044] The delivery particles may be cationic in nature, preferably cationic at a pH of 4.5. The delivery particles may be characterized by a ζ potential of at least 15 millivolts (mV) at a pH of 4.5. The delivery particles may be made to have a ζ potential of at least 15 millivolts (mV) at a pH of 4.5, or even a ζ potential of at least 40 mV at a pH of 4.5, or even a ζ potential of at least 60 mV at a pH of 4.5. Polyurea capsules prepared with chitosan generally exhibit a positive ζ potential. Such capsules have improved deposition efficiency on fabrics. At higher pH values, the particles can be made nonionic or anionic.

[0045] The delivery particles of the present disclosure include a shell surrounding a core. (As used herein, "shell" and "wall" may be used interchangeably with respect to the delivery particles unless otherwise specified.) The shell contains a polymeric material. The polymeric material is a reaction product of chitosan and a crosslinking agent.

[0046] The chitosan may be characterized in that it has a weight-average molecular weight of about 100 kDa to about 600 kDa. Preferably, the chitosan is characterized in that it has a weight-average molecular weight (Mw) of about 100 kDa to about 500 kDa, preferably about 100 kDa to about 400 kDa, more preferably about 100 kDa to about 300 kDa, and even more preferably about 100 kDa to about 200 kDa. Methods for determining the molecular weight and related parameters of chitosan are provided in the Test Methods section below and use gel permeation chromatography with multi-angle light scattering and refractive index detection (GPC-MALS / RI) technology. Selecting chitosan with a preferred weight-average molecular weight can produce capsules with suitable shell formation and / or desired processability.

[0047] Chitosan preferably used in the materials of the present disclosure is acid-treated chitosan. For example, chitosan (which may also be referred to as raw chitosan or parent chitosan before acid treatment) can be preferably acid-treated at a temperature of about 25 °C to about 99 °C, preferably about 75 °C to about 95 °C, at a pH of 6.5 or less for one hour, preferably one hour to about three hours. The acid can be selected from strong acids (such as hydrochloric acid), weak acids (such as formic acid or acetic acid), or mixtures thereof. The chitosan can be preferably acid-treated at a pH of 2 to 6.5, preferably 3 to 6, and even more preferably 4 to 6.

[0048] The acid-treated chitosan can be formed by treating chitosan with a mixture of acids (e.g., a mixed acid system). Preferably, the acid-treated chitosan is produced by treating chitosan with a mixture comprising a first acid and a second acid, where the first acid comprises a strong acid and where the second acid comprises a weak acid. As described in more detail above, it is believed that using the mixtures of acids described herein provides delivery particles with sufficient performance while, for example, minimizing risks to manufacturing equipment.

[0049] Preferably, chitosan is treated with the mixture at a pH of 6.5 or less, preferably at a pH less than 6.5, more preferably at a pH of 3 to 6, and at a temperature of at least 25 °C, preferably about 25 °C to about 99 °C, preferably about 75 °C to about 95 °C. Too low a temperature may result in incomplete reaction; too high a temperature may lead to undesired degradation of chitosan.

[0050] Acid treatment of chitosan can advantageously reduce the viscosity of the chitosan solution; a mixture with a lower viscosity can be more easily processed and / or result in improved capsule formation. It may be desirable to acid-treat chitosan for at least one hour, preferably about one hour to about three hours. It may be desirable to treat chitosan for a period of time to obtain a chitosan solution with a viscosity not exceeding about 1500 cps, preferably not exceeding 500 cps.

[0051] Treating chitosan according to the present disclosure enables a surprising reduction in the viscosity measured at the same concentration for a 3%, preferably 3.5%, more preferably 4% or higher concentration of chitosan solution. The viscosity of chitosan at such concentrations is typically in the range of 4000 centipoise (cP). The acid-treated chitosan at the same concentration treated according to the method of the present disclosure can show a viscosity reduction of 60% or even more than 60%, reaching a viscosity of 1500 cP, or even 1000 cP, or even 500 cP at the same concentration. By way of illustration, chitosan at a 3.5% concentration treated according to the present disclosure (which typically has an initial viscosity of 4000 cP) shows a viscosity reduction of 60% or even more than 60%, reaching a viscosity of 1500 cP or even 1000 cP at the same concentration.

[0052] It has been found that it is advantageous to use certain relative amounts of each acid in the mixture. For example, the first acid and the second acid are preferably present in an equivalent concentration ratio of from about 20:80 to about 80:20, preferably from about 35:65 to about 65:35. Without wishing to be bound by theory, it is believed that selecting the correct ratio results in delivery particles that are efficiently prepared, perform well and / or minimize the risk of corrosion.

[0053] The first acid may comprise, consist essentially of, or consist of a strong acid selected from the group consisting of hydrochloric acid, perchloric acid, nitric acid, sulfuric acid, and mixtures thereof, preferably hydrochloric acid.

[0054] The weak acid and / or the second acid may comprise, consist essentially of, or consist of a weak acid selected from the group consisting of formic acid, acetic acid, ascorbic acid, glutamic acid, lactic acid, maleic acid, malic acid, succinic acid, citric acid, acrylic acid, oxalic acid, tartaric acid, and mixtures thereof, preferably formic acid, acetic acid, and mixtures thereof.

[0055] The acid can be a monoprotic acid, a diprotic acid, or a polyprotic acid. For the purposes of the present disclosure, "polyprotic acid" includes "triprotic acid". It should be understood that a diprotic or polyprotic acid will have more than one ionizable hydrogen and thus will have a first or initial pKa and additional pKa values for the additional ionizable hydrogens. For the purposes herein, "first pKa" refers to the first or initial ionizable hydrogen when the acid is a diprotic or polyprotic acid.

[0056] The first acid preferably has a first pKa of less than 1. The second acid preferably has a first pKa of from about 1 to about 5.5. Preferably, both are true, where the first acid has a first pKa of less than 1 and the second acid has a first pKa of from about 1 to about 5.5.

[0057] As described above, the acid-treated chitosan can be formed by treating chitosan with a weak acid. To reduce the risk of corrosion, it is preferred that the chitosan used to prepare the shell of the delivery particles can be treated only with a weak acid. The weak acid can include a single weak acid, or the weak acid can include a mixture of weak acids. Suitable weak acids are described above.

[0058] Without wishing to be bound by theory, it is believed that the choice of weak acid may affect the final shell formation and the resulting properties of the delivery particles, at least in some product matrices. For example, as shown in the Examples section below, it is believed that chitosan treated with acetic acid can produce delivery particles that perform particularly well in liquid fabric softener compositions. Accordingly, the present disclosure relates to a treatment composition, such as a treatment composition that is a liquid fabric softener ("LFE") composition, wherein the composition comprises a population of delivery particles formed from acid-treated chitosan as described herein, wherein the acid-treated chitosan is produced by treating chitosan with an acid, wherein the acid comprises one or more weak acids and does not contain strong acids, and wherein the chitosan is treated with the acid at a pH of 6.5 or less and at a temperature of at least 25°C. Preferably, in such cases, the weak acid comprises acetic acid, or even consists essentially of acetic acid. Such compositions may comprise a conditioning active, such as an ester quaternary compound, which may be present in the composition at a level of from about 1% to about 35%, preferably from 2% to about 20% by weight of the composition. Suitable conditioning actives are described in more detail above.

[0059] Chitosan may include anionically modified chitosan, cationically modified chitosan, or combinations thereof. Modifying chitosan in an anionic and / or cationic manner alters the characteristics of the shell of the delivery particles, e.g., by changing the surface charge and / or zeta potential, which affects the deposition efficiency of the particles and / or the formulation compatibility.

[0060] As described above, the shell is a polymeric material that is the reaction product of chitosan and a crosslinker. Preferably, the crosslinker comprises a polyisocyanate. Accordingly, the shell of the delivery particles may comprise a polyurea resin, wherein the polyurea resin comprises the reaction product of a polyisocyanate and chitosan.

[0061] For the purposes of this disclosure, polyisocyanate materials useful in the present disclosure should be understood to be isocyanate monomers, isocyanate oligomers, isocyanate prepolymers, or dimers or trimers of aliphatic or aromatic isocyanates. "Polyisocyanate" means a material or compound containing two or more isocyanate moieties. All such monomers, prepolymers, oligomers, or dimers or trimers of aliphatic or aromatic isocyanates are intended to be encompassed by the term "polyisocyanate" herein. Polyisocyanates useful in the present disclosure include isocyanate monomers, oligomers, or prepolymers having at least two isocyanate groups, or dimers or trimers thereof. Polyisocyanates having at least three functional groups may be used to achieve preferred crosslinking.

[0062] Aromatic polyisocyanates may be preferred; however, aliphatic polyisocyanates and their blends may be useful. Aliphatic polyisocyanates are understood to be polyisocyanates that do not contain any aromatic moieties. Aliphatic polyisocyanates are understood to be polyisocyanates that contain at least one aromatic moiety. The crosslinking agent may comprise a mixture of aromatic polyisocyanates and aliphatic polyisocyanates.

[0063] When the polyisocyanate is aromatic, it may be, but is not limited to, methylene diphenyl diisocyanate, toluene diisocyanate, tetramethylxylidene diisocyanate, the polyisocyanurate of toluene diisocyanate (commercially available from Bayer under the trade name RC), the trimethylolpropane adduct of toluene diisocyanate (commercially available from Bayer under the trade name L75), the trimethylolpropane adduct of naphthalene-1,5-diisocyanate, phenylene diisocyanate or xylylene diisocyanate (commercially available from Mitsui Chemicals under the trade name D-110N).

[0064] Aliphatic polyisocyanates may include the trimer of hexamethylene diisocyanate, the trimer of isophorone diisocyanate, the trimethylolpropane adduct of hexamethylene diisocyanate (available from Mitsui Chemicals), or the biuret of hexamethylene diisocyanate (commercially available from Bayer under the trade name N 100).

[0065] Derivatives of polyisocyanates may include oligomers or polymers of isocyanate monomers. As a non-limiting example, the polyisocyanate may preferably include oligomers or polymers of diphenylmethane diisocyanate (MDI), such as MR-Light.

[0066] The polyisocyanate may preferably be selected from the group consisting of: the polyisocyanurate of toluene diisocyanate; the trimethylolpropane adduct of toluene diisocyanate; the trimethylolpropane adduct of xylylene diisocyanate; 2,2'-methylenediphenyl diisocyanate; 4,4'-methylenediphenyl diisocyanate; 2,4'-methylenediphenyl diisocyanate; [diisocyanato(phenyl)methyl]benzene; toluene diisocyanate; tetramethylxylidene diisocyanate; naphthalene-1,5-diisocyanate; 1,4-phenylene diisocyanate; 1,3-diisocyanatobenzene; their derivatives (such as their prepolymers, oligomers and / or polymers); and combinations thereof.

[0067] Additional co-crosslinking agents such as polyfunctional amines and / or polyamines such as diethylenetriamine (DETA), polyethyleneimine, polyvinylamine, or mixtures thereof can also be used to strengthen the particle shell. Acrylates can also be used as additional co-crosslinking agents, for example, to strengthen the shell.

[0068] The polymeric material can be formed in a reaction where the weight ratio of chitosan present in the reaction to the crosslinking agent present in the reaction is from about 1:10 to about 1:0.1. It is believed that selecting the desired ratio of biopolymer to crosslinking agent can provide desired ductility benefits as well as improved biodegradability. Preferably, at least 21 wt% of the shell can comprise a portion derived from chitosan, preferably from acid-treated chitosan. The weight percentage of chitosan in the shell can be from about 21% to about 95% of the shell. Based on weight, the ratio of chitosan in the aqueous phase to isocyanate in the oil phase can be from 21:79 to 90:10, or even from 1:2 to 10:1, or even from 1:1 to 7:1. The shell can contain chitosan in an amount of 21 wt% or even higher, preferably from about 21 wt% to about 90 wt%, or even from 21 wt% to 85 wt%, or even from 21 wt% to 75 wt%, or 21 wt% to 55 wt% of the total shell of chitosan. The chitosan in this paragraph can preferably be acid-treated chitosan.

[0069] A population of delivery particles can be prepared according to a method comprising the steps of: (a) forming an aqueous phase by treating the chitosan with a mixture of a first acid and a second acid, the first acid comprising a strong acid and the second acid comprising a weak acid, wherein the chitosan is treated at a pH of 6.5 or less, or even less than pH 6.5, or even at a pH of 3 to 6 and at a temperature of less than 25 °C for at least one hour, preferably from one hour to three hours; (b) forming an oil phase comprising dissolving at least one beneficial agent and at least one crosslinking agent, preferably a polyisocyanate, optionally with an added oil (e.g., a partitioning modifier) and / or a solvent; (c) forming an emulsion by mixing the aqueous phase and the oil phase into an excess of the aqueous phase under high-shear agitation, thereby forming droplets of the oil phase (which contains the beneficial agent) dispersed in the aqueous phase, and optionally adjusting the pH of the emulsion to within the range of pH 2 to pH 6; (d) curing the emulsion by heating to at least 40 °C for a time sufficient to form a shell at the interface between the droplets and the aqueous phase, the shell comprising the reaction product of the crosslinking agent and the acid-treated chitosan, and the shell surrounding the core comprising the beneficial agent.

[0070] Chitosan can be added to the water in a jacketed reactor and adjusted using strong acids (such as concentrated HCl) and weak acids (such as formic acid or acetic acid) at a pH of 2 or even 3 to 6.5. The chitosan in the mixture can be acid-treated by heating to an elevated temperature (such as 85 °C) for 60 minutes and then held at that temperature for 1 minute to 1440 minutes or longer. Then the aqueous phase can be cooled to 25 °C. Optionally, deacetylation can also be further promoted or enhanced by enzymes to depolymerize or deacetylate the chitosan. The oil phase can be prepared by dissolving an isocyanate such as a trimer of xylylene diisocyanate (XDI) or a polymer of methylene diphenyl diisocyanate (MDI) in oil at 25 °C. A diluent (e.g., isopropyl myristate) can be used to adjust the hydrophobicity of the oil phase. Then the oil phase can be added to the aqueous phase and ground at high speed to obtain the target size. Then the emulsion can be cured in one or more heating steps, such as heating to 40 °C in 30 minutes and holding at 40 °C for 60 minutes. The time and temperature are approximate. The temperature and time are selected to be sufficient to form and cure a shell at the interface of the droplets of the oil phase and the water continuous phase. For example, the emulsion can be heated to 85 °C in 60 minutes and then held at 85 °C for 360 minutes to cure the particles. Then the slurry can be cooled to room temperature.

[0071] When tested according to test method OECD 301B, the shell can degrade by at least 50% after 20 days (or less). When tested according to test method OECD 301B, the shell can degrade at least 60% of its mass after 60 days (or less). When tested according to test method OECD 301B, the shell can preferably degrade at least 60% of its mass after 60 days (or less). The shell can degrade 30% to 100%, preferably 40% to 100%, 50% to 100%, 60% to 100% or 60% to 95% after 60 days, preferably 50 days, more preferably 40 days, more preferably 28 days, more preferably 14 days.

[0072] The delivery particles of the present disclosure include a core. The core contains a beneficial agent. The core optionally contains a dispensing modifier.

[0073] The core of the particle is surrounded by a shell. When the shell ruptures, the beneficial agent in the core is released. Additionally or alternatively, the beneficial agent in the core can diffuse out of the particle, and / or the beneficial agent can be extruded. Suitable beneficial agents located in the core can include beneficial agents that provide beneficial effects to surfaces (such as fabrics or hair).

[0074] The core can contain from about 5% to about 100% of the beneficial agent by weight of the core, which can preferably contain a fragrance. The core can contain from about 45% to about 95%, preferably from about 50% to about 80%, more preferably from about 50% to about 70% of the beneficial agent by weight of the core, which can preferably contain a fragrance.

[0075] The beneficial agent may include an aldehyde-containing beneficial agent, a ketone-containing beneficial agent, or a combination thereof. Such beneficial agents (e.g., aldehyde / ketone-containing fragrance raw materials) are known to provide preferred beneficial effects, such as a refreshing beneficial effect. The beneficial agent may include at least about 20%, preferably at least about 25%, more preferably at least about 40%, and even more preferably at least about 50% of an aldehyde-containing beneficial agent, a ketone-containing beneficial agent, or a combination thereof, based on the weight of the beneficial agent.

[0076] The beneficial agent may be a hydrophobic beneficial agent. Such agents are compatible with the oil phase commonly used in preparing the delivery particles of the present disclosure.

[0077] The beneficial agent is selected to provide a benefit in the case of preferably using the treatment composition. The beneficial agent in the core may be selected from the group consisting of: fragrance materials, silicone oils, waxes, hydrocarbons, higher fatty acids, essential oils, lubricants, lipids, skin coolants, vitamins, sunscreens, antioxidants, glycerin, catalysts, bleaching agent particles, silica particles, malodor attenuators, odor control materials, chelating agents, antistatic agents, softeners, insect and moth repellents, colorants, base agents, disinfection drapes and morphology control agents, smoothers, wrinkle control agents, hygienic treatment agents, disinfectants, microbial control agents, mildew control agents, mold control agents, antiviral agents, desiccants, antifouling agents, detergents, fabric fresheners and freshness extenders, chlorine bleach odor control agents, dye fixatives, dye transfer inhibitors, color retention agents, optical brighteners, color recovery / restoration agents, anti-fading agents, whiteness enhancers, anti-abrasion agents, anti-wear agents, fabric integrity agents, anti-pilling agents, defoaming agents, ultraviolet protection agents, photo-fading inhibitors, anti-allergic agents, enzymes, water repellents, fabric comfort agents, anti-shrinkage agents, anti-stretching agents, stretch recovery agents, skin care agents, synthetic or natural active substances, antibacterial active substances, antiperspirant active substances, cationic polymers, dyes, and mixtures thereof.

[0078] The beneficial agent in the core preferably includes a fragrance material (or simply referred to as "fragrance"), which may include one or more fragrance raw materials. The fragrance is particularly suitable for encapsulation in the delivery particles described in the present invention because the fragrance-containing particles can provide a refreshing beneficial effect across multiple contact points.

[0079] As used herein, the term "perfume raw material" (or "PRM") refers to a compound having a molecular weight of at least about 100 g / mol, and which can be used alone or in combination with other perfume raw materials to impart an odor, aroma, fragrance or scent. Typical PRMs include, in particular, alcohols, ketones, aldehydes, esters, ethers, nitrites and olefins, such as terpenes. Lists of common PRMs can be found in various references, such as "Perfume and Flavor Chemicals", Volumes I and II; Steffen Arctander Allured Pub. Co. (1994) and "Perfumes: Art, Science and Technology", Miller, P.M. and Lamparsky, D., Blackie Academic and Professional (1994).

[0080] PRMs can be characterized by their boiling point (B.P.) measured at normal pressure (760 mmHg), and their octanol / water partition coefficient (P), which can be described as logP and is determined according to the test methods below. Based on these properties, PRMs can be classified as Quadrant I perfumes, Quadrant II perfumes, Quadrant III perfumes or Quadrant IV perfumes, as described in more detail in U.S. Patent 6,869,923. Suitable Quadrant I perfume raw materials, Quadrant II perfume raw materials, Quadrant III perfume raw materials and Quadrant IV perfume raw materials are disclosed herein.

[0081] Perfume raw materials having a boiling point B.P. of less than about 250 °C and a logP of less than about 3 are referred to as Quadrant I perfume raw materials. Quadrant I perfume raw materials are preferably limited to less than 30% of the fragrance material.

[0082] The fragrance can include perfume raw materials having a logP of about 2.5 to about 4. It should be understood that other perfume raw materials may also be present in the fragrance.

[0083] The core of the delivery particles of the present disclosure can include a partitioning modifier that can promote more robust shell formation. The partitioning modifier can be combined with the perfume oil material of the core before incorporation of the wall-forming monomers. The partitioning modifier can be present in the core at a level of 0% to 95%, preferably about 5% to about 55%, preferably about 10% to about 50%, more preferably about 20% to about 50%, and even more preferably about 25% to about 50% by weight of the core.

[0084] The partitioning modifier can include materials selected from the group consisting of vegetable oils, modified vegetable oils, C4-C 24Mono-esters, di-esters and tri-esters of fatty acids, isopropyl myristate, lauryl benzophenone, lauryl laurate, methyl behenate, methyl laurate, methyl palmitate, methyl stearate and mixtures thereof. The partitioning modifier may preferably comprise isopropyl myristate or even consist of isopropyl myristate. The modified vegetable oil may be esterified and / or brominated. The modified vegetable oil may preferably comprise castor oil and / or soybean oil. U.S. Patent Application Publication 20110268802, which is incorporated herein by reference, describes other partitioning modifiers that may be used in the delivery particles described herein.

[0085] When the beneficial agent itself is not sufficient to serve as the oil phase or solvent, particularly during the formation of the shell of the delivery particle of the wall-forming material, the oil phase may comprise a suitable carrier and / or solvent. In this sense, the oil is optional since the beneficial agent itself can sometimes be an oil. These carriers or solvents are generally oils, preferably having a boiling point greater than about 80 °C and low volatility and being non-flammable. Although not limited thereto, they preferably comprise one or more esters, preferably esters having a chain length of up to 18 carbon atoms or even up to 42 carbon atoms and / or triglycerides, such as esters of C6 to C12 fatty acids and glycerol.

[0086] Optionally, the aqueous phase may comprise an emulsifier. Non-limiting examples of emulsifiers include anionic surfactants (such as alkyl sulfates, alkyl ether sulfates and / or alkyl benzene sulfonates), non-ionic surfactants (such as alkoxylated alcohols, preferably containing ethoxy), polyvinyl alcohol, and / or polyvinyl pyrrolidone. It is possible in the present application that dissolved chitosan may provide emulsification benefits. The emulsifier, if employed, is typically from about 0.1 wt% to 40 wt%, preferably 0.2 wt% to about 15 wt%, more typically 0.5 wt% to 10 wt% based on the total weight of the aqueous phase.

[0087] The population of delivery particles may be provided as a slurry, preferably an aqueous slurry. The slurry may comprise one or more processing aids, which may include water, aggregation-inhibiting materials such as divalent salts, or particulate suspension polymers such as xanthan gum, guar gum, cellulose (preferably microfibrillated cellulose) and / or carboxymethyl cellulose. When the delivery particles are characterized by a cationic nature (e.g., when the shell is at least partially derived from chitosan), non-anionic structuring agents, preferably non-ionic structuring agents may be preferred, for example to avoid detrimental charge interactions that may lead to undesirable aggregation.

[0088] The slurry may comprise one or more carriers selected from the group consisting of: polar solvents including, but not limited to, water, ethylene glycol, propylene glycol, polyethylene glycol, glycerol; non-polar solvents including, but not limited to, mineral oil, perfume raw materials, silicone oil, hydrocarbon paraffin oil; and mixtures thereof. An aqueous slurry may be preferred. The slurry may comprise unencapsulated ( "free") perfume raw materials that differ in unit and / or amount from those encapsulated in the core of the delivery particles.

[0089] The slurry may comprise a deposition aid, which may include polymers selected from the group comprising: polysaccharides such as chitosan, cationically modified starch and / or cationically modified guar gum; polysiloxanes; diallyldimethylammonium halide; copolymers of diallyldimethylammonium chloride and polyvinylpyrrolidone; compositions comprising polyethylene glycol and polyvinylpyrrolidone; acrylamide; imidazole; imidazoline halide; polyvinylamine; copolymers of polyvinylamine and N-vinylformamide; polyvinylformamide, polyvinyl alcohol; polyvinyl alcohol crosslinked with boric acid; polyacrylic acid; polyglycerol ether silicone crosslinked polymer; copolymers of polyacrylic acid, polyacrylate, polyvinylamine and polyvinyl alcohol oligomers with amines, in one aspect, diethylenetriamine, ethylenediamine, bis(3-aminopropyl)piperazine, N,N-bis-(3-aminopropyl)methylamine, tris(2-aminoethyl)amine and mixtures thereof; polyethyleneimine, derivatized polyethyleneimine, in one aspect, ethoxylated polyethyleneimine; polymeric compounds comprising at least two moieties on the backbone of polybutadiene, polyisoprene, polybutadiene / styrene, polybutadiene / acrylonitrile, carboxyl-terminated polybutadiene / acrylonitrile or combinations thereof, the at least two moieties being selected from the group consisting of carboxylic acid moieties, amine moieties, hydroxyl moieties and nitrile moieties; preformed coacervates of anionic surfactants in combination with cationic polymers; polyamines, and mixtures thereof.

[0090] At least one population of delivery particles may be included in an agglomerate and then combined with a different population of delivery particles and at least one adjuvant material. The agglomerate may comprise materials selected from the group consisting of: silica, citric acid, sodium carbonate, sodium sulfate, sodium chloride and substrates such as sodium silicate, modified cellulose, polyethylene glycol, polyacrylate, polyacrylic acid, zeolite, and mixtures thereof.

[0091] Suitable apparatuses for use in the methods disclosed herein can include continuous stirred tank reactors, homogenizers, turbine agitators, recycle pumps, paddle mixers, plowshare shear mixers, ribbon blenders, vertical axis granulators, and tumbling mixers (the latter two of which can be in batch process configurations and continuous process configurations (when available)), spray dryers, and extruders. Such apparatuses can be purchased from Lodige GmbH (Paderborn, Germany), Littleford Day, Inc. (Florence, Ky., U.S.A.), Forberg AS (Larvik, Norway), Glatt Ingenieurtechnik GmbH (Weimar, Germany), Niro (Soeborg, Denmark), Hosokawa Bepex Corp. (Minneapolis, Minn., U.S.A.), Arde Barinco (New Jersey, U.S.A.).

[0092] Adjuvant component

[0093] In addition to delivering particles, the treatment compositions of the present disclosure can include one or more adjuvant materials. The adjuvant materials can provide beneficial effects in the intended end use of the composition, or they can be processing aids and / or stabilizing aids.

[0094] Suitable adjuvant materials can include: surfactants, conditioning actives, deposition aids, rheology modifiers or structurants, bleaching systems, stabilizers, builders, chelating agents, dye transfer inhibitors, dispersants, enzymes and enzyme stabilizers, catalytic metal complexes, polymeric dispersants, clays and soil removal / anti-redeposition agents, optical brighteners, defoamers, silicones, hueing agents, aesthetic dyes, additional fragrances and fragrance delivery systems, structural elasticizers, carriers, hydrotropes, processing aids, anti-caking agents, coatings, formaldehyde scavengers, and / or pigments. Preferably, the adjuvant materials include additional fabric conditioners, dyes, pH control agents, solvents, rheology modifiers, structurants, cationic polymers, surfactants, fragrances, additional fragrance delivery systems, chelating agents, antioxidants, preservatives, or mixtures thereof.

[0095] Depending on the desired form, formulation, and / or end use, the compositions of the present disclosure may not contain one or more of the following adjuvant materials: bleach activators, surfactants, builders, chelating agents, dye transfer inhibitors, dispersants, enzymes and enzyme stabilizers, catalytic metal complexes, polymeric dispersants, clays and soil removal / antiredeposition agents, optical brighteners, antifoaming agents, dyes, additional fragrances and fragrance delivery systems, structurants, fabric softeners, carriers, hydrotropes, processing aids, structurants, anti-caking agents, coatings, formaldehyde scavengers, and / or pigments.

[0096] The exact nature and the amounts incorporated of these additional components will depend on the physical form of the composition and the nature of the operations for which it is used. However, when one or more adjuvants are present, such one or more adjuvants may be present as detailed below. The following is a non-limiting list of suitable additional adjuvants.

[0097] A. Surfactant

[0098] The compositions of the present disclosure may contain surfactants. For example, surfactants can be used to provide cleaning benefits. The composition may contain a surfactant system, which may contain one or more surfactants.

[0099] The compositions of the present disclosure may contain from about 0.1% to about 70%, or from about 2% to about 60%, or from about 5% to about 50% by weight of the composition of the surfactant system. Liquid compositions may contain from about 5% to about 40% by weight of the composition of the surfactant system. Compact formulations, including compact liquids, gels, and / or compositions suitable for unit dosage forms, may contain from about 25% to about 70% or from about 30% to about 50% by weight of the composition of the surfactant system.

[0100] The surfactant system may include anionic surfactants, nonionic surfactants, zwitterionic surfactants, cationic surfactants, amphoteric surfactants, or combinations thereof. The surfactant system may include linear alkylbenzene sulfonates, alkyl ethoxylated sulfates, alkyl sulfates, nonionic surfactants such as ethoxylated alcohols, amine oxides, or mixtures thereof. The surfactant may be at least partially derived from natural sources, such as natural raw material alcohols.

[0101] Suitable anionic surfactants can include any conventional anionic surfactant. This can include sulfate detergent surfactants (such as alkoxylated and / or non-alkoxylated alkyl sulfate materials) and / or sulfonate detergent surfactants (such as alkylbenzene sulfonates). The anionic surfactant can be linear, branched, or a combination thereof. Preferred surfactants include linear alkylbenzene sulfonates (LAS), alkyl ethoxylated sulfates (AES), alkyl sulfates (AS), or mixtures thereof. Other suitable anionic surfactants include branched-modified alkylbenzene sulfonates (MLAS), methyl ester sulfonates (MES), sodium lauryl sulfate (SLS), sodium lauryl ether sulfate (SLES), and / or alkyl ethoxylated carboxylates (AEC). The anionic surfactant can be present in acid form, salt form, or a mixture thereof. The anionic surfactant can be partially or fully neutralized with, for example, an alkali metal (such as sodium) or an amine (such as monoethanolamine). Due to the presence of the cationic ester quaternary compound material, it may be desirable to limit the amount of the anionic surfactant to avoid undesirable interactions of the materials; for example, the composition can contain less than 5%, preferably less than 3%, more preferably less than 1%, even more preferably less than 0.1% of the anionic surfactant by weight of the composition.

[0102] The surfactant system can include nonionic surfactants. Suitable nonionic surfactants include alkoxylated fatty alcohols, such as ethoxylated fatty alcohols. Other suitable nonionic surfactants include alkoxylated alkylphenols, alkylphenol condensates, mid-chain branched alcohols, mid-chain branched alkyl alkoxylates, alkyl polysaccharides (such as alkyl polyglycosides), polyhydroxy fatty acid amides, ether-capped poly(alkoxylated) alcohol surfactants, and mixtures thereof. The alkoxylate units can be ethyleneoxy units, propyleneoxy units, or a mixture thereof. The nonionic surfactant can be linear, branched (such as mid-chain branched), or a combination thereof. Specific nonionic surfactants can include alcohols having an average of about 12 to about 16 carbon atoms and an average of about 3 to about 9 ethoxy groups, such as a C12-C14 EO7 nonionic surfactant.

[0103] Suitable zwitterionic surfactants can include any conventional zwitterionic surfactant, such as betaines, including alkyl dimethyl betaines and coco dimethyl amidopropyl betaines, C8 to C 18 (e.g., C 12 to C 18 ) amine oxides (e.g., C 12-14 dimethyl amine oxide), and / or sulfobetaines and hydroxybetaines, such as N-alkyl-N,N-dimethylamino-1-propane sulfonates, where the alkyl group can be C8 to C 18 or C 10 to C 14The zwitterionic surfactant may include amine oxide.

[0104] Depending on the formulation and / or intended end use, the composition may be substantially free of certain surfactants. For example, liquid fabric enhancer compositions, such as fabric softeners, may be substantially free of anionic surfactants because such surfactants can interact unfavorably with cationic components.

[0105] b. Conditioning active substance

[0106] The compositions of the present disclosure may contain conditioning actives. Compositions containing conditioning actives may provide softness, wrinkle resistance, antistatic, conditioning, anti-stretch, color, and / or appearance benefits.

[0107] The conditioning actives may be present at a level of about 1% to about 99% by weight of the composition. The composition may contain about 1%, or about 2%, or about 3% to about 99%, or up to about 75%, or up to about 50%, or up to about 40%, or up to about 35%, or up to about 30%, or up to about 25%, or up to about 20%, or up to about 15%, or up to about 10% by weight of the composition of the conditioning actives. The composition may contain about 5% to about 30% by weight of the conditioning actives.

[0108] Conditioning actives suitable for the compositions of the present disclosure may include quaternary ammonium ester compounds, silicones, non-ester quaternary ammonium compounds, amines, fatty esters, sucrose esters, silicones, dispersible polyolefins, polysaccharides, fatty acids, softening or conditioning oils, polymer latexes, or combinations thereof. Preferably, the treatment composition is a fabric care composition, wherein the one or more adjuvant components comprise a quaternary ammonium ester substance; such materials are particularly suitable for use in fabric enhancing / conditioning / softening compositions.

[0109] The composition may contain a quaternary ammonium ester compound, silicone, or a combination thereof, preferably a combination. The total amount of the combination of the quaternary ammonium ester compound and silicone may be about 5% to about 70%, or about 6% to about 50%, or about 7% to about 40%, or about 10% to about 30%, or about 15% to about 25% by weight of the composition. The composition may contain a quaternary ammonium ester compound and silicone in a weight ratio of about 1:10 to about 10:1, or about 1:5 to about 5:1, or about 1:3 to about 1:3, or about 1:2 to about 2:1, or about 1:1.5 to about 1.5:1, or about 1:1.

[0110] The composition may contain a mixture of different types of conditioning actives. The compositions of the present disclosure may contain certain conditioning actives but be substantially free of other conditioning actives. For example, the composition may be free of quaternary ammonium ester compounds, silicones, or both. The composition may contain a quaternary ammonium ester compound but be substantially free of silicones. The composition may contain silicones but be substantially free of quaternary ammonium ester compounds.

[0111] C. Deposition aid

[0112] The compositions of the present disclosure may include deposition aids. As described above, due to the synergistic beneficial effects from the ester quaternary ammonium compound materials and the delivery particles of the present disclosure, relatively little (or even no) deposition aid may be required to provide similar or even improved performance; alternatively, deposition aids may be used in the compositions of the present disclosure to further enhance performance.

[0113] Deposition aids may facilitate the deposition of delivery particles, conditioning actives, fragrances, or combinations thereof, thereby improving the performance benefits of the composition and / or allowing for more efficient formulation of such beneficial agents. The composition may include from 0.0001% to 3%, preferably from 0.0005% to 2%, more preferably from 0.001% to 1%, or about 0.01% to about 0.5%, or about 0.05% to about 0.3% by weight of the composition of the deposition aid. The deposition aid may be a cationic polymer or an amphoteric polymer, preferably a cationic polymer.

[0114] Generally speaking, cationic polymers and their methods of manufacture are known in the literature. Suitable cationic polymers may include quaternary ammonium polymers referred to as "polyquaternium" polymers, as designated by the International Nomenclature for Cosmetic Ingredients, such as polyquaternium-6 (poly(diallyldimethylammonium chloride)), polyquaternium-7 (copolymer of acrylamide and diallyldimethylammonium chloride), polyquaternium-10 (quaternized hydroxyethyl cellulose), polyquaternium-22 (copolymer of acrylic acid and diallyldimethylammonium chloride), and the like.

[0115] The deposition aid may be selected from the group consisting of polyvinylformamide, partially hydroxylated polyvinylformamide, polyvinylamine, polyvinylimine, ethoxylated polyvinylimine, polyvinyl alcohol, polyacrylate, and combinations thereof. The cationic polymer may include cationic acrylates.

[0116] The deposition aid may be added simultaneously with the delivery particles (simultaneously with, for example, the encapsulated beneficial agent) or added directly / independently to the consumer product composition. As measured by size exclusion chromatography relative to a polyethylene oxide standard using refractive index (RI) detection, the weight average molecular weight of the polymer may be from 500 Daltons to 5,000,000 Daltons, or from 1,000 Daltons to 2,000,000 Daltons, or from 2,500 Daltons to 1,500,000 Daltons. The weight average molecular weight of the cationic polymer may be from 5,000 Daltons to 37,500 Daltons.

[0117] D. Rheology modifier / structurant

[0118] The compositions of the present disclosure may comprise a rheology modifier and / or a structuring agent. The rheology modifier can be used to "thicken" or "thin" a liquid composition to a desired viscosity. The structuring agent can be used to promote phase stability and / or suspend or inhibit aggregation of particles in a liquid composition, such as the delivery particles described herein.

[0119] Suitable rheology modifiers and / or structuring agents can include non-polymeric crystalline hydroxy-functionalized structuring agents (including those based on hydrogenated castor oil), polymeric structuring agents, cellulose fibers (e.g., microfibrillated cellulose, which can be derived from bacterial, fungal, or plant sources, including wood), diacylamino gelling agents, or combinations thereof.

[0120] The polymeric structuring agents can be of natural origin or synthetic origin. Polymeric structuring agents of natural origin can include: hydroxyethyl cellulose, hydrophobically modified hydroxyethyl cellulose, carboxymethyl cellulose, polysaccharide derivatives, and mixtures thereof. Polysaccharide derivatives can include: pectin, alginate, arabinogalactan (gum arabic), carrageenan, gellan gum, xanthan gum, guar gum, and mixtures thereof. Synthetic polymeric structuring agents can include: polycarboxylates, polyacrylates, hydrophobically modified ethoxylated polyurethanes, hydrophobically modified nonionic polyols, and mixtures thereof. Polycarboxylate polymers can include polyacrylates, polymethacrylates, or mixtures thereof. Polyacrylates can include copolymers of unsaturated monocarboxylic or dicarboxylic acids with C1-C 30 alkyl esters of (meth)acrylic acid. Such copolymers are available from Noveon under the trade name Carbopol Aqua 30. Crosslinked polymers, such as crosslinked polyacrylates, and / or polymers and / or copolymers, such as those further comprising nonionic monomers (such as acrylamide or methacrylamide monomers), can be used as structuring agents. Another suitable structuring agent is sold under the trade name Rheovis CDE and is available from BASF.

[0121] E. Other adjuvants

[0122] The treatment compositions of the present disclosure can comprise other adjuvants suitable for inclusion in a product and / or suitable for end use. For example, the treatment composition can comprise neat fragrance, fragrance delivery technologies (such as pre-fragrances and / or encapsulates having non-polyisocyanate / chitosan wall materials), cationic surfactants, cationic polymers, solvents, antifoaming agents, or combinations thereof.

[0123] Method for preparing a treatment composition

[0124] The present disclosure also relates to methods for preparing treatment compositions, such as those treatment compositions and / or consumer product compositions described herein.

[0125] The method may comprise the steps of: providing a base composition, wherein the base composition comprises the treatment adjuvant; and combining the population of delivery particles with the base composition. The population of delivery particles may preferably be provided as an aqueous slurry. The base composition is in the form of a liquid composition.

[0126] When the delivery particles are in one or more forms (including slurry form, pure particle form, and / or spray-dried particle form), preferably in slurry form, the delivery particles may be combined with one or more adjuvant components. The delivery particles may be combined with such adjuvants by methods including mixing and / or spraying.

[0127] At least a portion of the method of preparing the treatment composition may occur on manufacturing equipment comprising stainless steel, preferably 316L stainless steel. The population of delivery particles may be part of an aqueous slurry that contacts at least a portion of the stainless steel, preferably 316L stainless steel. Since stainless steel is susceptible to corrosion, for example, in the presence of chloride ions, it may be desirable to keep the amount of chloride ions to a minimum. Thus, preferably, the slurry may comprise less than 0.4%, preferably less than or equal to 0.37%, preferably less than 0.2%, more preferably less than or equal to 0.17% chloride ions (Cl - ) by weight of the slurry. When forming the delivery particles, reducing the amount of HCl used and / or using a weak acid to treat chitosan may reduce the relative amount of chloride ions.

[0128] The treatment composition of the present disclosure may be formulated into any suitable form and prepared by any method chosen by the formulator. The one or more adjuvant components and the delivery particles may be combined in a batch method, in a recycle loop method, and / or by an in-line mixing method. Suitable equipment for use in the methods disclosed herein may include continuous stirred tank reactors, homogenizers, turbine agitators, recycle pumps, paddle mixers, high-shear mixers, static mixers, plow shear mixers, ribbon blenders, vertical axis granulators, and drum mixers (the latter two may be in batch process configurations and continuous process configurations (when available)), spray dryers, and extruders.

[0129] The treatment composition may be placed in a container to form a consumer product as described herein. The container may be a bottle, preferably a plastic bottle. The treatment composition may be placed in an aerosol or other spray container according to known methods.

[0130] Treatment method

[0131] The present disclosure also relates to a method of treating a surface, preferably a fabric. Generally, the method comprises the step of contacting the surface, preferably the fabric, with a treatment composition according to the present disclosure, wherein the treatment composition comprises a population of delivery particles as described herein.

[0132] Additionally or alternatively, the method may include the step of contacting a surface, preferably a fabric, with a population of delivery particles as described herein. The population of delivery particles may be included in a treatment composition according to the present disclosure, preferably a fabric care composition.

[0133] The method may include the step of contacting a fabric (such as a piece of clothing) with a treatment composition. The treatment composition includes a population of delivery particles. The contacting step results in the deposition of one or more of the delivery particles on the surface of the fabric. The delivery particles include a core and a shell surrounding the core, wherein the core includes a benefit agent, preferably an aromatic material, which aromatic material includes one or more fragrance ingredients. The shell includes a polymeric material, for example, the polymeric material is a reaction product of chitosan of a specific molecular weight and a crosslinking agent. Suitable treatment compositions and delivery particles are described in more detail above.

[0134] The contacting step may occur in a washbasin during a manual laundry process, such as when handling the fabric by hand, or during an automatic laundry process, such as in an automatic washing machine. The contacting step may occur during the wash cycle of an automatic washing machine; in such cases, the treatment composition may be a laundry detergent or a laundry wash additive. The contacting step may preferably occur during the rinse cycle of an automatic washing machine; in such cases, the treatment composition may be a fabric enhancer, preferably a liquid fabric enhancer. The contacting step may even occur during the drying step of a laundry process, such as in an automatic dryer; in such cases, the treatment composition may be in the form of a nonwoven dryer sheet or a dryer bar. The contacting step may occur due to, for example, directly applying the treatment composition to the fabric during a pretreatment operation or during a "refreshing" step (e.g., for a fabric that has been used or worn since its last wash); in such cases, the treatment composition may be in the form of a liquid, a bar, or a spray, preferably a spray. Contacting the target fabric relatively late in a laundry process (e.g., during the rinse cycle) increases the likelihood or efficiency of deposition onto the fabric because the treatment composition is less likely to be rinsed down the drain at this time.

[0135] The contacting step may occur in the presence of water. The treatment composition may be diluted with water to form a treatment liquid. The treatment composition may be diluted from about 100-fold to about 1500-fold, preferably from 300-fold to about 1000-fold.

[0136] A liquid containing the disclosed composition may have a pH of from about 3 to about 11.5. Such compositions are typically used at a concentration of from about 500 ppm to about 15,000 ppm in solution when diluted. When the wash solvent is water, the water temperature is typically in the range of from about 5 °C to about 90 °C, and the ratio of water to fabric may typically be from about 1:1 to about 30:1.

[0137] Dilution can occur in the drum of an automatic washing machine. The treatment composition can be placed in the dispensing drawer of the automatic washing machine. During the treatment process, the treatment composition can be dispensed from the dispensing drawer into the drum.

[0138] As described above, the method can further include a step of drying the fabric that has one or more delivery particles on the surface of the fabric. The drying step can include a passive drying process, such as on a clothesline or drying rack. The drying step can include an automatic drying process, such as in an automatic dryer.

[0139] Combination

[0140] Specifically contemplated combinations of the present disclosure are described herein in the following lettered paragraphs. These combinations are illustrative in nature and not restrictive.

[0141] A. A treatment composition, the treatment composition comprising a treatment adjuvant and a population of delivery particles, wherein the delivery particles comprise a core and a shell surrounding the core, wherein the core comprises a beneficial agent, wherein the shell comprises a polymeric material that is a reaction product of an acid-treated chitosan and a crosslinking agent, wherein the acid-treated chitosan is produced by treating chitosan with a mixture of a first acid and a second acid, the first acid comprising a strong acid, the second acid comprising a weak acid, wherein the first acid and the second acid are present in an equivalent concentration ratio of from about 20:80 to about 80:20, preferably from 35:65 to about 65:35, and wherein the chitosan is treated with the mixture at a pH of 6.5 or less and at a temperature of at least 25°C.

[0142] B. The treatment composition according to paragraph A, wherein the first acid comprises a strong acid selected from the group consisting of hydrochloric acid, perchloric acid, nitric acid, sulfuric acid, and mixtures thereof, preferably hydrochloric acid.

[0143] C. The treatment composition according to any one of paragraphs A or B, wherein the second acid comprises a weak acid selected from the group consisting of formic acid, acetic acid, ascorbic acid, glutamic acid, lactic acid, maleic acid, malic acid, succinic acid, citric acid, acrylic acid, oxalic acid, tartaric acid, and mixtures thereof, preferably formic acid, acetic acid, and mixtures thereof.

[0144] D. The treatment composition according to any one of paragraphs A to C, wherein the first acid has a first pKa of less than 1, and the second acid has a first pKa of from about 1 to about 5.5.

[0145] E. A treating composition according to any one of paragraphs A to D, wherein the chitosan is characterized in that the weight average molecular weight is from about 100 kDa to about 600 kDa, preferably from about 100 kDa to about 500 kDa, more preferably from about 100 kDa to about 400 kDa, more preferably from about 100 kDa to about 300 kDa, and even more preferably from about 100 kDa to about 200 kDa.

[0146] F. A treating composition according to any one of paragraphs A to E, wherein the crosslinking agent comprises a polyisocyanate, preferably a polyisocyanate selected from the group consisting of: polyisocyanurate of toluene diisocyanate; trimethylolpropane adduct of toluene diisocyanate; trimethylolpropane adduct of xylylene diisocyanate; 2,2'-methylenediphenyl diisocyanate; 4,4'-methylenediphenyl diisocyanate; 2,4'-methylenediphenyl diisocyanate; [diisocyanato(phenyl)methyl]benzene; toluene diisocyanate;

[0147] tetramethylbenzene diisocyanate; naphthalene-1,5-diisocyanate; 1,4-phenylene diisocyanate; 1,3-diisocyanatobenzene; their derivatives (such as their prepolymers, oligomers and / or polymers); and combinations thereof.

[0148] G. A treating composition according to any one of paragraphs A to F, wherein the reaction product is formed in a reaction, and the weight ratio of the chitosan present in the reaction to the crosslinking agent present in the reaction is from about 1:10 to about 1:0.1.

[0149] H. A treating composition according to any one of paragraphs A to G, wherein the beneficial agent is an aromatic material, preferably an aromatic material comprising a perfume raw material, and the perfume raw material is characterized in that the logP is from about 2.5 to about 4.5.

[0150] I. A treating composition according to any one of paragraphs A to H, wherein the core further comprises a partitioning modifier optionally present in the core at a level of from about 5% to about 55%, preferably from about 10% to about 50%, more preferably from about 25% to about 50% by weight of the core, and preferably a partitioning modifier selected from the group consisting of: vegetable oil, modified vegetable oil, monoesters, diesters and triesters of C4-C 24 isopropyl myristate, lauryl benzophenone, lauryl laurate, methyl behenate, methyl laurate, methyl palmitate, methyl stearate and mixtures thereof, and more preferably isopropyl myristate.

[0151] J. A treating composition according to any one of paragraphs A to I, wherein the delivery particles are characterized by a volume weighted median particle size of from about 1 micron to about 100 microns, preferably from about 10 microns to about 100 microns, preferably from about 15 microns to about 50 microns, more preferably

[0152] from about 20 microns to about 40 microns, and even more preferably from about 25 microns to about 35 microns. K. A treating composition according to any one of paragraphs A to J, wherein the delivery particles

[0153] can be obtained from a method comprising the steps of: forming an aqueous phase by treating the chitosan with the mixture of the first acid and the second acid, wherein the chitosan is treated at a pH of 6.5 or less, preferably at a pH of less than 6.5, more preferably at a pH of 3 to 6 and at a temperature of at least 25 °C for at least one hour to form acid-treated chitosan; forming an oil phase, the forming step comprising: dissolving at least one beneficial agent and at least one crosslinking agent, preferably a polyisocyanate, optionally with an added oil, preferably a partitioning modifier; forming an emulsion by: preferably mixing the oil phase into an excess of the aqueous phase under high shear agitation to form droplets of the oil phase dispersed in the aqueous phase, and optionally adjusting the pH of the emulsion to within the range of pH 2 to pH 6; curing the emulsion at a temperature of at least 40 °C for a time sufficient to form a shell at the interface between the droplets and the aqueous phase, the shell comprising the reaction product of the crosslinking agent and the acid-treated chitosan, and the shell surrounding the core comprising the oil phase of the droplets.

[0154] L. A treating composition according to any one of paragraphs A to K, wherein the delivery particles are cationic, preferably wherein the delivery particles are characterized by a ζ potential of at least 15 mV at a pH of 4.5.

[0155] M. A treating composition according to any one of paragraphs A to L, wherein when tested according to test method OECD 301B, the shell of the delivery particles degrades by at least 60% within 60 days.

[0156] N. A treatment composition according to any one of paragraphs A to M, wherein the treatment adjuvant is selected from the group consisting of: surfactants, conditioning actives, deposition aids, rheology modifiers or structurants, bleaching systems, stabilizers, builders, chelating agents, dye transfer inhibitors, dispersants, enzymes, enzyme stabilizers, catalytic metal complexes, polymeric dispersants, clays and soil removal / antiredeposition agents, optical brighteners, antifoaming agents, silicones, colorants, aesthetic dyes, perfume, additional perfume delivery systems, structure elasticizers, carriers, hydrotropes, processing aids, antiagglomerants, coatings, formaldehyde scavengers, pigments, and mixtures thereof.

[0157] O. A treatment composition according to any one of paragraphs A to N, wherein the treatment adjuvant comprises an anionic surfactant, a cationic conditioner, or a mixture thereof.

[0158] T. A treatment composition according to any one of paragraphs A to O, wherein the treatment composition is a fabric care composition, a hard surface cleaner composition, a dish care composition, a hair care composition, a body cleansing composition, or a mixture thereof, preferably a fabric care composition, more preferably a fabric care composition as a laundry detergent composition, a fabric conditioner composition, a laundry additive, a fabric pretreatment composition, a fabric freshener composition, or a mixture thereof.

[0159] Q. A treatment composition according to any one of paragraphs A to P, wherein the treatment composition is in the form of a liquid composition, a particulate composition, an aqueous colloid, a single-compartment sachet, a multi-compartment sachet, a soluble sheet, a lozenge or bead, a fibrous article, a tablet, a bar, a strip, a wafer, a foam / mousse, a nonwoven sheet, or a mixture thereof, preferably in the form of a liquid composition.

[0160] R. A treatment composition according to any one of paragraphs A to Q, wherein the treatment composition comprises from about 50% to about 99% water, preferably from about 60% to about 98%, more preferably from about 80% to about 96% water, by weight of the treatment composition.

[0161] S. A method of preparing a treatment composition according to any one of paragraphs A to R, the method comprising the steps of: providing a base composition, wherein the base composition comprises the treatment adjuvant; and combining the delivery particle population with the base composition.

[0162] T. A method according to paragraph S, wherein the delivery particle population is part of an aqueous slurry, wherein the slurry comprises less than 0.4%, preferably less than or equal to 0.37%, preferably less than 0.2%, more preferably less than or equal to 0.17% chloride ions (Cl -)。

[0163] U. A method according to any one of paragraphs S or T, wherein the method takes place on manufacturing equipment comprising 316L stainless steel, and wherein the slurry contacts at least a portion of the 316L stainless steel.

[0164] V. A method of treating a surface, the method comprising the step of contacting the surface, preferably a fabric, with a treatment composition according to any one of paragraphs A to R.

[0165] W. A treatment composition comprising a treatment adjuvant and a population of delivery particles, wherein the delivery particles comprise a core and a shell surrounding the core, wherein the core comprises a beneficial agent, wherein the shell comprises a polymeric material which is a reaction product of an acid-treated chitosan and a crosslinking agent, wherein the acid-treated chitosan is produced by treating chitosan with an acid, wherein the acid comprises one or more weak acids, and wherein the chitosan is treated with the acid at a pH of 6.5 or less and at a temperature of at least 25 °C; and wherein the treatment adjuvant comprises a conditioning active substance.

[0166] X. A treatment composition according to paragraph W, wherein the acid does not contain strong acids.

[0167] Y. A treatment composition according to any one of paragraphs W or X, wherein the weak acid is selected from

[0168] the group consisting of formic acid, acetic acid, ascorbic acid, glutamic acid, lactic acid, maleic acid, malic acid, succinic acid, citric acid, acrylic acid, oxalic acid, tartaric acid, and mixtures thereof, preferably formic acid, acetic acid, and mixtures thereof, and even more preferably acetic acid.

[0169] Test method

[0170] It should be understood that the test methods disclosed in the test method section of the present application should be used to determine the corresponding parameter values of the subject matter claimed by the applicant as claimed and described herein.

[0171] Determination of polymer molecular weight and related parameters

[0172] The method described below for gel permeation chromatography with multi-angle light scattering and refractive index detection (GPC-MALS / RI) is used to find the molecular weight distribution measurements and related values of the polymers described herein.

[0173] Gel Permeation Chromatography with Multi-Angle Light Scattering (MALS) and Refractive Index (RI) Detection (GPC-MALS / RI) allows the measurement of the absolute molecular weight of polymers without the need for column calibration methods or standards. The GPC system allows molecules to be separated according to their molecular size. MALS and RI allow the obtaining of information on the number-average (Mn) and weight-average (Mw) molecular weights.

[0174] The Mw distribution of water-soluble polymers such as chitosan is typically measured using a liquid chromatography system (e.g., an Agilent 1260 Infinity pump system with OpenLab Chemstation software, Agilent Technology, Santa Clara, CA, USA) and a column set operating at 40 °C (e.g., 2 Tosoh TSKgel G6000WP 7.8×300 mm 13 um pore size, guard column A0022 6 mm×40 mm PW xl-cp, King of Prussia, PA). The mobile phase is an aqueous solution of 0.1 M sodium nitrate containing 0.02% sodium azide and 0.2% acetic acid. The mobile phase solvent is pumped isocratically at a flow rate of 1 mL / min. Using a multi-angle light scattering (18-Angle MALS) detector controlled by Wyatt software v8.0 and a differential refractive index (RI) detector (Wyatt Technology, Santa Barbara, California, USA).

[0175] Typically, samples are prepared by dissolving the chitosan material in the mobile phase at approximately 1 mg / ml and hydrating the solution by mixing overnight at room temperature. Before GPC analysis, the sample is filtered through a 0.8 μm Versapor membrane filter (PALL, Life Sciences, NY, USA) into an LC autosampler vial using a 3 ml syringe.

[0176] The number-average molecular weight (Mn), weight-average molecular weight (Mw), z-average molecular weight (Mz), molecular weight at the peak maximum (Mp), and polydispersity (Mw / Mn) are determined using the dn / dc value (differential change of refractive index with concentration, 0.15) by the Astra detector software.

[0177] Viscosity

[0178] The viscosity of the liquid finished product is measured using an AR 550 rheometer / viscometer from TA Instruments (New Castle, DE, USA), with parallel steel plates having a diameter of 40 mm and a gap size of 500 μm. 20 s-1 The high-shear viscosity at and 0.05 s -1 The low-shear viscosity at is obtained from a logarithmic shear rate sweep from 0.01 s -1 to 25 s -1 over a 3-minute period at 21 °C.

[0179] Test method for determining logP

[0180] Calculate the logarithm (logP) of the octanol / water partition coefficient for each material tested (e.g., each PRM in the flavor blend). Calculate the logP of the individual material (e.g., PRM) using the Consensus logP Computational Model version 14.02 (Linux) purchased from Advanced Chemistry Development Inc. (ACD / Labs) (Toronto, Canada) to provide a dimensionless logP value. The Consensus logP Computational Model from ACD / Labs is part of the ACD / Labs model suite.

[0181] Volume-weighted particle size and size distribution

[0182] Determine the volume-weighted particle size distribution by single particle optical sensing (SPOS) (also known as optical particle counting (OPC)) using an AccuSizer 780AD instrument and the accompanying software CW788 version 1.82 (Particle Sizing Systems, Santa Barbara, California, U.S.A.) or equivalent. The instrument is configured with the following conditions and selections: flow rate = 1 ml / sec; lower size threshold = 0.50 μm; sensor model = LE400-05 or equivalent; auto dilution = on; collection time = 60 seconds; number of channels = 512; container fluid volume = 50 ml; maximum coincidence = 9200. Start the measurement by flushing the sensor with water until the background count is less than 100 to bring it to a cold state. Introduce the sample in suspension of the delivery capsule and adjust the density of the capsule with DI water by auto dilution as needed to obtain a capsule count of at least 9200 / ml. Analyze the suspension over a 60-second period. Plot and record the resulting volume-weighted PSD data and determine the values of the volume-weighted particle sizes required (e.g., median / 50th percentile, 5th percentile, and / or 90th percentile).

[0183] Procedure for determining % degradation

[0184] To determine % degradation, the procedure described in the "OECD Guideline for Testing of Chemicals" 301B CO2 Evolution (Modified Sturm Test), adopted on July 17, 1992, was used. For ease of reference, this test method is referred to herein as Test Method OECD 301B.

[0185] Fabric treatment method

[0186] A Miele washing machine was used to process the fabric. For each treatment, the washing machine was loaded with 3 kg of fabric, which consisted of 1100 g of knitted cotton fabric and 1100 g of polyester cotton fabric (50 / 50). Additionally, 18 thick terrycloth cotton tracers were added, with a total weight of approximately 780 g.

[0187] Before the test treatment, the load was pretreated twice, each time using a 95 °C short cotton cycle with 79 g of unperfumed IEC A basic detergent (purchased from WFK Testgewebe GmbH), followed by two additional 95 °C washes without detergent.

[0188] For the test treatment, the load was washed using a 40 °C short cotton cycle, a spin speed of 1200 rpm, and 79 g of IEC A basic detergent, which was added to the appropriate dispenser at the start of the wash cycle. A 35 g dose of the test fabric treatment composition (i.e., LFE according to the example) was added to the appropriate dispenser. At the end of the treatment cycle, the thick terrycloth tracers were removed from the washing machine and air-dried overnight.

[0189] The next day, the dried thick terrycloth tracers were analyzed by the rapid headspace GC / MS (gas chromatography - mass spectrometry) method described below. All treatments washed and analyzed on the same day for comparison purposes were reported as "one - wash tests".

[0190] Olfactory assessment method

[0191] After the fabric was treated, a professional perfumer performed an olfactory assessment of the fragrance intensity at the DRY contact point (dry fabric odor = DFO) and the RUB contact point (rubbed fabric odor = RFO) on the dry fabric. The fabric was dried for one day, the DFO was smelled, then the fabric was manually manipulated by rubbing it against itself, and the RFO was smelled again; the scores were averaged. The scores were based on a fragrance odor intensity scale of 0 to 100, where 0 = no fragrance odor, 25 = slight fragrance odor, 50 = moderate fragrance odor, 75 = strong fragrance odor, and 100 = extremely strong fragrance odor.

[0192] Method for determining the headspace concentration above a treated dry fabric

[0193] The cotton tracer was analyzed by a rapid headspace GC / MS (gas chromatography - mass spectrometry) method. A 4X4 cm aliquot of the flannel towel cotton tracer was transferred to a 25 mL headspace vial. The fabric sample was equilibrated at 65 °C for 10 minutes. The headspace above the fabric was sampled for 5 minutes via the SPME (50 / 30 μm DVB / Carboxen / PDMS) method. Subsequently, the SPME fiber was thermally desorbed immediately into the GC. The analytes were analyzed by rapid GC / MS in the full - scan mode. The total HS response above the test leg and the fragrance headspace composition were calculated using ion extraction of specific masses with PRM.

[0194] Examples

[0195] The examples provided below are essentially intended to be illustrative and not restrictive.

[0196] Comparative Example 1.

[0197] The aqueous phase was prepared by dispersing 92.19 g of chitosan (ULV grade, Primex EHF, Siglufjörður, Iceland) into 1956.6 g of water while mixing in a jacketed reactor. Then, the pH of the aqueous phase was adjusted to 5.37 using 39.16 g of concentrated HCl (hydrochloric acid, 32% to 38%, Avantor Performance Materials, Radnor, Pennsylvania) with stirring. Then, the temperature of the aqueous phase was raised to 95 °C within 90 minutes and then held at 95 °C for a period of time (such as 2 hours) for acid treatment of the chitosan. Then, after the acid - treatment step, the temperature of the aqueous phase was lowered to 25 °C within a 90 - minute period.

[0198] The oil phase was prepared by mixing 716.36 g of fragrance oil and 179.10 g of isopropyl myristate (Acme - Hardesty Co., Blue Bell, Pennsylvania) together with 19.59 g of Takenate D - 110N (Mitsui Chemicals America, Inc., Rye Brook, New York) at room temperature. The oil phase was added to the aqueous phase under high - shear milling to obtain an emulsion. The emulsion was heated to 65 °C within 45 minutes and then to 85 °C within 60 minutes. Then, the emulsion was held at that temperature for 6 hours while mixing. The delivered particle population of the final slurry had a volume - weighted median particle size of 28.84 microns.

[0199] Comparative Example 2.

[0200] The aqueous phase was prepared by dispersing 101.26 g of chitosan (ULV grade, Primex EHF, Siglufjördur, Iceland) into 2153.18 g of water while mixing in a jacketed reactor. Then, 8.42 g of concentrated HCl (hydrochloric acid, 32% to 38%, Avantor Performance Materials, Radnor, PA) was added to the chitosan mixture with stirring. Then, the pH of the aqueous phase was adjusted to 5.43 using 16.26 g of 90% formic acid (Brenntag Great Lakes, LLC, Wauwatosa, WI). Then, the temperature of the aqueous phase was raised to 95 °C within 90 minutes and then held at 95 °C for a period of time (such as 2 hours) for acid treatment of the chitosan. Then, after the acid treatment step, the temperature of the aqueous phase was lowered to 25 °C within a 90-minute period.

[0201] The oil phase was prepared by mixing 786.74 g of flavor oil and 196.71 g of isopropyl myristate (Acme-Hardesty Co., Blue Bell, PA) together with 21.53 g of Takenate D-110N (Mitsui Chemicals America, Inc., Rye Brook, NY) at room temperature. The oil phase was added to the aqueous phase under high-shear milling to obtain an emulsion. The emulsion was heated to 65 °C within 45 minutes and then to 85 °C within 60 minutes. Then, the emulsion was held at that temperature for 6 hours while mixing. The delivered particle population of the final slurry had a volume-weighted median particle size of 26.26 microns.

[0202] Comparative Example 3.

[0203] The aqueous phase was prepared by dispersing 12.35 lb of chitosan (ULV grade, Primex EHF, Siglufjördur, Iceland) into 262.10 lb of water while mixing in a jacketed tank. Then, the pH of the aqueous phase was adjusted to 5.19 using 2.7 lb of 90% formic acid (Brenntag Great Lakes, LLC, Wauwatosa, WI) with stirring. Then, the temperature of the aqueous phase was raised to 95 °C within 90 minutes and then held at 95 °C for a period of time (such as 2 hours) for acid treatment of the chitosan. Then, after the acid treatment step, the temperature of the aqueous phase was lowered to 25 °C within a 90-minute period.

[0204] The oil phase was prepared by mixing 78.2 pounds of spice oil and 42 pounds of isopropyl myristate (Acme-Hardesty Co., Blue Bell, Pennsylvania) together with 2.6 pounds of Takenate D-110N (Mitsui Chemicals America, Inc., Rye Brook, New York) in a jacketed tank at room temperature. The oil phase was added to the aqueous phase under high-shear milling to obtain an emulsion. The emulsion was heated to 65 °C in 45 minutes and then to 85 °C in 60 minutes. The emulsion was then held at that temperature for 6 hours while mixing. The delivery particle population of the final slurry had a volume-weighted median particle size of 32.11 microns.

[0205] Example 1.

[0206] The aqueous phase was prepared by dispersing 101.31 g of chitosan (ULV grade, Primex EHF, Siglufjörður, Iceland) into 2149.03 g of water while mixing in a jacketed reactor. Then 25.19 g of concentrated HCl (hydrochloric acid, 32% to 38%, Avantor Performance Materials, Radnor Township, Pennsylvania) was added to the chitosan mixture with stirring. Then the pH of the aqueous phase was adjusted to 5.43 using 8.5 g of 90% formic acid (Brenntag Great Lakes, LLC, Wauwatosa, Wisconsin) with stirring. Then the temperature of the aqueous phase was raised to 95 °C in 90 minutes and then held at 95 °C for a period of time (such as 2 hours) for acid treatment of the chitosan. Then the temperature of the aqueous phase was lowered to 25 °C in a 90-minute period after the acid treatment step.

[0207] The oil phase was prepared by mixing 786.70 g of spice oil and 196.68 g of isopropyl myristate (Acme-Hardesty Co., Blue Bell, Pennsylvania) together with 21.57 g of Takenate D-110N (Mitsui Chemicals America, Inc., Rye Brook, New York) in a jacketed tank at room temperature. The oil phase was added to the aqueous phase under high-shear milling to obtain an emulsion. The emulsion was heated to 65 °C in 45 minutes and then to 85 °C in 60 minutes. The emulsion was then held at that temperature for 6 hours while mixing. The delivery particle population of the final slurry had a volume-weighted median particle size of 25.65 microns.

[0208] Example 2.

[0209] The aqueous phase was prepared by dispersing 12.31 lbs of chitosan (ULV grade, Primex EHF, Siglufjördur, Iceland) into 261.33 lbs of water while mixing in a jacketed tank. Then, 3.07 lbs of concentrated HCl (hydrochloric acid, 32% to 38%, Avantor Performance Materials, Radnor, PA) was added to the chitosan mixture with stirring. Then, the pH of the aqueous phase was adjusted to 5.22 using 1.11 lbs of 90% formic acid (Brenntag Great Lakes, LLC, Wauwatosa, WI) with stirring. Then, the temperature of the aqueous phase was raised to 95 °C within 90 minutes and then held at 95 °C for a period of time (such as 2 hours) to acid-treat the chitosan. Then, after the acid-treatment step, the temperature of the aqueous phase was lowered to 25 °C within a 90-minute period.

[0210] The oil phase was prepared by mixing 95.68 lbs of spice oil and 23.92 lbs of isopropyl myristate (Acme-Hardesty Co., Blue Bell, PA) together with 2.62 lbs of Takenate D-110N (Mitsui Chemicals America, Inc., Rye Brook, NY) in a jacketed tank at room temperature. The oil phase was added to the aqueous phase under high-shear milling to obtain an emulsion. The emulsion was heated to 65 °C within 45 minutes and then to 85 °C within 60 minutes. Then, the emulsion was held at that temperature for 6 hours while mixing. The delivered particle population of the final slurry had a volume-weighted median particle size of 28.82 microns. According to the 301B test, the percentage of shell degradation was 54.95% at 28 days.

[0211] Example 3.

[0212] The aqueous phase was prepared by dispersing 101.30 g of chitosan (ULV grade, Primex EHF, Siglufjördur, Iceland) into 2148.95 g of water while mixing in a jacketed reactor. Then, 16.80 g of concentrated HCl (hydrochloric acid, 32% to 38%, Avantor Performance Materials, Radnor, PA) was added to the chitosan mixture with stirring. Then, the pH of the aqueous phase was adjusted to 5.43 using 12.44 g of 90% formic acid (Brenntag Great Lakes, LLC, Wauwatosa, WI) with stirring. Then, the temperature of the aqueous phase was raised to 95 °C within 90 minutes and then held at 95 °C for a period of time (such as 2 hours) to acid-treat the chitosan. Then, after the acid-treatment step, the temperature of the aqueous phase was lowered to 25 °C within a 90-minute period.

[0213] The oil phase was prepared by mixing 786.73 g of perfume oil and 196.69 g of isopropyl myristate (Acme-Hardesty Co., Blue Bell, Pennsylvania) together with 21.56 g of Takenate D-110N (Mitsui Chemicals America, Inc., Rye Brook, New York) at room temperature. The oil phase was added to the aqueous phase under high-shear milling to obtain an emulsion. The emulsion was heated to 65 °C in 45 minutes and then to 85 °C in 60 minutes. The emulsion was then held at that temperature for 6 hours while mixing. The delivery particle population of the final slurry had a volume-weighted median particle size of 26.57 microns.

[0214] Example 4.

[0215] The aqueous phase was prepared by dispersing 101.26 g of chitosan (ULV grade, Primex EHF, Siglufjördur, Iceland) into 2149.6 g of water while mixing in a jacketed reactor. Then 25.22 g of concentrated HCl (hydrochloric acid, 32% to 38%, Avantor Performance Materials, Radnor Township, Pennsylvania) was added to the chitosan mixture with stirring. Then the pH of the aqueous phase was adjusted to 5.45 using 24.34 g of 40% acetic acid (Columbus Chemical Industries, Inc., Columbus, Wisconsin) with stirring. Then the temperature of the aqueous phase was raised to 95 °C in 90 minutes and then held at 95 °C for a period of time (such as 2 hours) for acid treatment of the chitosan. Then the temperature of the aqueous phase was lowered to 25 °C in a 90-minute period after the acid treatment step.

[0216] The oil phase was prepared by mixing 786.71 g of perfume oil and 196.68 g of isopropyl myristate (Acme-Hardesty Co., Blue Bell, Pennsylvania) together with 21.51 g of Takenate D-110N (Mitsui Chemicals America, Inc., Rye Brook, New York) at room temperature. The oil phase was added to the aqueous phase under high-shear milling to obtain an emulsion. The emulsion was heated to 65 °C in 45 minutes and then to 85 °C in 60 minutes. The emulsion was then held at that temperature for 6 hours while mixing. The delivery particle population of the final slurry had a volume-weighted median particle size of 30.93 microns.

[0217] Example 5.

[0218] The aqueous phase was prepared by dispersing 101.28 g of chitosan (ULV grade, Primex EHF, Siglufjörður, Iceland) into 2139.74 g of water while mixing in a jacketed reactor. Then 16.82 g of concentrated HCl (hydrochloric acid, 32% to 38%, Avantor Performance Materials, Radnor, PA) was added to the chitosan mixture with stirring. Then the pH of the aqueous phase was adjusted to 5.45 using 36.78 g of 40% acetic acid (Columbus Chemical Industries, Inc., Columbus, WI) with stirring. Then the temperature of the aqueous phase was raised to 95 °C over 90 minutes and then held at 95 °C for a period of time (such as 2 hours) to acid-treat the chitosan. Then after the acid treatment step, the temperature of the aqueous phase was lowered to 25 °C over a 90-minute period.

[0219] The oil phase was prepared by mixing 786.74 g of fragrance oil and 196.68 g of isopropyl myristate (Acme-Hardesty Co., Blue Bell, PA) together with 21.51 g of Takenate D-110N (Mitsui Chemicals America, Inc., Rye Brook, NY) at room temperature. The oil phase was added to the aqueous phase under high shear milling to obtain an emulsion. The emulsion was heated to 65 °C over 45 minutes and then to 85 °C over 60 minutes. Then the emulsion was held at that temperature for 6 hours while mixing. The delivered particle population of the final slurry had a volume-weighted median particle size of 28.84 microns.

[0220] Example 6. Chitosan treated with a single acid

[0221] To compare the performance of delivered particles made from chitosan materials that had been treated with various single acids, three populations of delivered particles were prepared.

[0222] Chitosan was treated with hydrochloric acid, formic acid, and acetic acid, respectively. Perfume delivery particles were prepared according to the present disclosure, wherein the shell was made of acid-treated chitosan and crosslinked with polyisocyanate. The core of the delivered particles on average contained approximately 80% of a first perfume and approximately 20% of a partitioning modifier (i.e., isopropyl myristate). The volume-weighted average particle size of the particle populations was approximately 12 to 14 microns.

[0223] To test the freshness performance of the resulting delivered particles, samples of a liquid fabric enhancer (“LFE”) were prepared using the different delivered particles described above. The test LFE composition contained approximately 6 wt% of a diester quaternary compound. Based on the weight of the LFE composition, the chitosan-based delivered particles were present in the test LFE composition at a level to provide approximately 0.2% of the encapsulated fragrance. The pH of the test LFE composition was adjusted to approximately 3.

[0224] The fabric is treated according to the fabric treatment method provided in the Test Methods section above. The fabric is evaluated for dry fabric odor (DFO) and rubbed fabric odor (RFO) according to the olfactory evaluation method provided in the Test Methods section above. The results are provided in Table 1 below.

[0225] Additionally, delivery particles are provided to a heavy-duty liquid (HDL) detergent matrix and leakage is tested after one week of storage. The percentage of leakage is provided in Table 1.

[0226] Table 1 .

[0227]

[0228] * = Comparative example

[0229] As shown in Table 1, compared to delivery particles made from chitosan treated with strong acid (i.e., hydrochloric acid), delivery particles made from chitosan treated with weak acid (i.e., formic acid or acetic acid) provide comparable or even better freshness performance based on olfactory evaluation. It is also expected that the weak acid will improve the corrosion curve of the relevant slurry.

[0230] Interestingly, when delivery particles are provided to an LFE product, acetic acid seems to provide improved freshness performance compared to formic acid. However, as shown in Table 2, compared to particles made from chitosan treated with formic acid, particles made from chitosan treated with acetic acid show a relatively poor leakage curve in an HDL product. Additionally, it should be noted that the slurry of particles made from chitosan treated with acetic acid shows some gelling, which may pose processing challenges.

[0231] Example 7. Effect of mixed acid treatment on the freshness performance of particles

[0232] To compare the freshness performance of delivery particles made from chitosan materials that have undergone various acid treatments, samples of liquid fabric enhancer ("LFE") are prepared with the different delivery particles described above.

[0233] For each trial, the core of the delivery particles on average contains approximately 65% to 80% of a second fragrance and approximately 20% to 35% of a partitioning modifier (i.e., isopropyl myristate).

[0234] Test LFE compositions with the general formula provided in Table 2 are prepared. Based on the weight of the LFE composition, chitosan-based delivery particles are present in the test LFE composition at a level to provide approximately 0.2% of encapsulated fragrance. The pH of the test LFE composition is adjusted to approximately 3.

[0235] Table 2 .

[0236] Ingredients Active substance % (w / w) <![CDATA[Diester quaternary ammonium compound 1 > 6％ Encapsulated perfume oil provided in chitosan-based delivery particles 0.2％ Formic acid 0.045％ Hydrochloric acid 0.0075％ Sodium hydroxyethanediphosphonate 0.0071％ <![CDATA[Structuring agent (cationic polymer) 2 > 0.11％ Defoamer (silicone) 0.004％ Water Balance pH Approximately 3

[0237] 1 N,N - bis(tallow acyloxyethyl)-N,N - dimethyl ammonium chloride, from Evonik

[0238] 2 Flosoft FS222, from SNF

[0239] Treat the fabric according to the fabric treatment method provided in the Test Methods section above. Evaluate the fabric for dry fabric odor (DFO) and rubbed fabric odor (RFO) according to the olfactory evaluation method provided in the Test Methods section above.

[0240] A. Formic acid

[0241] Results for capsules made from chitosan that has been at least partially treated with formic acid are provided in Table 3 below.

[0242] Table 3 .

[0243]

[0244] * = Comparative Example

[0245] Based on the data in Table 3, compared to delivery particles formed from chitosan treated solely with HCl, delivery particles formed from chitosan treated with a mixed acid system (e.g., strong:weak equivalent concentration ratio from 80:20 to 20:80, where the weak acid is formic acid) provide comparable olfactory performance (e.g., RFO > 50). However, due to the presence of the weak acid, it is believed that such systems will have relatively low corrosivity.

[0246] The data in Table 3 also show that delivery particles made from chitosan treated with an acid system having a relatively high amount (e.g., equivalent concentration ratio less than 20:80) of formic acid (weak acid) result in relatively poor performance (e.g., RFO below 46).

[0247] B. Acetic acid

[0248] Results for capsules made from chitosan that has been at least partially treated with acetic acid are provided in Table 3 below.

[0249] Table 4 .

[0250]

[0251] * = Comparative Example

[0252] Based on the data in Table 4, compared to the delivery particles formed from chitosan treated solely with HCl, the delivery particles formed from chitosan treated with a mixed acid system (e.g., a strong:weak equivalent concentration ratio from 80:20 to 20:80, where the weak acid is acetic acid) provide comparable or even improved olfactory performance (e.g., RFO > 50). However, due to the presence of the weak acid, it is believed that such systems will have relatively low corrosivity.

[0253] In addition, based on the individual data collected by the applicant, it is believed that the delivery particles formed from chitosan treated solely with acetic acid (e.g., in terms of leakage in a liquid detergent matrix) are sub-optimal. Therefore, for performance reasons, it is believed that there is a desire for a certain minimum level of strong acid such as HCl.

[0254] Example 8. Effect of slurry chloride level on corrosion

[0255] The following tests were run to examine the effect of the chloride level in the delivery particle slurry on the corrosion of stainless steel materials commonly used in manufacturing equipment.

[0256] Chitosan was treated with formic acid and used to prepare fragrance delivery particles according to the method described in the present disclosure. Samples of the resulting particle slurry were admixed with magnesium chloride (MgCl2) to provide slurries with different chloride levels.

[0257] Stainless steel specimens (grade = 316L SS; dimensions = 3 / 4" × 2" × 1 / 8", with a 120 grit sandblasted finish) were placed in trays at approximately 38 °C and subjected to a wet / dry test that included periodically wetting the specimens with the slurry samples over the course of twenty-eight days (i.e., dipped on the first day and then every seven days). At the end of the treatment, the specimens were examined for pitting due to corrosion. The total number of pits on the front and back of the specimens was counted and reported in Table 5 below.

[0258] Table 5 .

[0259] Group Chloride in slurry wt % Total number of pits I* 0.64％ 8 J* 0.49％ 8 K 0.37％ 2 L 0.17％ 0

[0260] * = Comparative Example

[0261] As shown in Table 5, relatively low amounts of chloride ions in the slurry result in fewer pits, indicating less corrosion. Based on the data in Table 5, slurries with a chloride level of less than 0.4% are preferred, with a level of less than 0.2% being even more preferred.

[0262] The dimensions and values disclosed herein are not to be understood as being strictly limited to the exact numerical values recited. Instead, each such dimension is intended to mean the recited value and a functionally equivalent range surrounding that value. For example, a dimension disclosed as "40 mm" is intended to mean "about 40 mm".

[0263] Unless expressly excluded or otherwise limited, each document cited herein, including any cross-referenced or related patent or patent application and any patent application or patent to which this application claims priority or benefits thereof, is hereby incorporated by reference in its entirety. The citation of any document is not an admission that it is prior art with respect to any invention disclosed or claimed herein or that it alone, or in any combination with any one or more other references, teaches, suggests, or discloses any such invention. Further, when any meaning or definition of a term in this invention conflicts with any meaning or definition of the same term in a document incorporated by reference, the meaning or definition assigned to the term in this invention shall govern.

[0264] Although specific embodiments of the invention have been illustrated and described, it will be apparent to those skilled in the art that various other changes and modifications can be made without departing from the spirit and scope of the invention. Accordingly, it is intended that all such changes and modifications that fall within the scope of the invention be covered by the appended claims.

Claims

1. A treatment composition, the treatment composition comprising a treatment adjuvant and a population of delivery particles, wherein the delivery particles comprise a core and a shell surrounding the core, wherein the core comprises a beneficial agent, wherein the shell comprises a polymeric material which is a reaction product of an acid-treated chitosan and a crosslinking agent, wherein the acid-treated chitosan is produced by treating chitosan with a mixture of a first acid and a second acid, the first acid comprising a strong acid, the second acid comprising a weak acid, wherein the first acid and the second acid are present in an equivalent concentration ratio of about 20:80 to about 80:20, preferably about 35:65 to about 65:35, and wherein the chitosan is treated with the mixture at a pH of 6.5 or less and at a temperature of at least 25 °C.

2. The treatment composition according to claim 1, wherein the first acid comprises a strong acid selected from the group consisting of hydrochloric acid, perchloric acid, nitric acid, sulfuric acid, and mixtures thereof, preferably hydrochloric acid.

3. The treatment composition according to any one of claims 1 or 2, wherein the second acid comprises a weak acid selected from the group consisting of formic acid, acetic acid, ascorbic acid, glutamic acid, lactic acid, maleic acid, malic acid, succinic acid, citric acid, acrylic acid, oxalic acid, tartaric acid, and mixtures thereof, preferably formic acid, acetic acid, and mixtures thereof.

4. The treatment composition according to any one of the preceding claims, wherein the first acid has a first pKa of less than 1, and the second acid has a first pKa of about 1 to about 5.

5.

5. The treatment composition according to any one of the preceding claims, wherein the chitosan is characterized by a weight average molecular weight of about 100 kDa to about 600 kDa, preferably about 100 kDa to about 500 kDa, more preferably about 100 kDa to about 400 kDa, more preferably about 100 kDa to about 300 kDa, even more preferably about 100 kDa to about 200 kDa.

6. The treatment composition according to any one of the preceding claims, wherein the crosslinking agent comprises a polyisocyanate, preferably a polyisocyanate selected from the group consisting of polyisocyanurate of toluene diisocyanate; trimethylolpropane adduct of toluene diisocyanate; trimethylolpropane adduct of xylylene diisocyanate; 2,2'-methylenediphenyl diisocyanate; 4,4'-methylenediphenyl diisocyanate; 2,4'-methylenediphenyl diisocyanate; [diisocyanato(phenyl)methyl]benzene; toluene diisocyanate; tetramethylxylylene diisocyanate; naphthalene-1,5-diisocyanate; 1,4-phenylene diisocyanate; 1,3-diisocyanatobenzene; derivatives thereof (such as their prepolymers, oligomers, and / or polymers); and combinations thereof.

7. The treatment composition according to any one of the preceding claims, wherein the reaction product is formed in a reaction, wherein the weight ratio of the chitosan present in the reaction to the crosslinking agent present in the reaction is about 1:10 to about 1:0.

1.

8. The treatment composition according to any one of the preceding claims, wherein the beneficial agent is an aromatic material, preferably an aromatic material comprising a perfume raw material, the perfume raw material being characterized in that the logP is from about 2.5 to about 4.

5.

9. The treatment composition according to any one of the preceding claims, wherein the core further comprises a partitioning modifier optionally present in the core at a level of from about 5% to about 55%, preferably from about 10% to about 50%, more preferably from about 25% to about 50% by weight of the core, Preferably select a dispensing modifier from the group consisting of: vegetable oil, modified vegetable oil, mono-esters, di-esters and tri-esters of C4-C 24 isopropyl myristate, lauryl benzophenone, lauryl laurate, methyl behenate, methyl laurate, methyl palmitate, methyl stearate and mixtures thereof, more preferably isopropyl myristate.

10. The treatment composition according to any one of the preceding claims, wherein the delivery particles are characterized in that the volume weighted median particle size is from about 1 micron to about 100 microns, preferably from about 10 microns to about 100 microns, preferably from about 15 microns to about 50 microns, more preferably from about 20 microns to about 40 microns, even more preferably from about 25 microns to about 35 microns.

11. The treatment composition according to any one of the preceding claims, wherein the delivery particles can be obtained from a method comprising the steps of: forming an aqueous phase by treating the chitosan with the mixture of the first acid and the second acid, wherein the chitosan is treated at a pH of 6.5 or less, preferably at a pH of less than 6.5, more preferably at a pH of 3 to 6 and at a temperature of at least 25 °C for at least one hour to form an acid-treated chitosan; forming an oil phase, the forming step comprising: dissolving at least one beneficial agent and at least one crosslinking agent, preferably a polyisocyanate, optionally with an added oil, preferably a partitioning modifier, together; forming an emulsion by: preferably mixing the oil phase into an excess of the aqueous phase under high shear agitation to form droplets of the oil phase dispersed in the aqueous phase, and optionally adjusting the pH of the emulsion to within the range of pH 2 to pH 6; curing the emulsion at a temperature of at least 40 °C for a time sufficient to form a shell at the interface between the droplets and the aqueous phase, the shell comprising the reaction product of the crosslinking agent and the acid-treated chitosan, and the shell surrounding the core comprising the droplets of the oil phase.

12. The treatment composition according to any one of the preceding claims, wherein the delivery particles are cationic, preferably wherein the delivery particles are characterized in that the ζ potential is at least 15 mV at a pH of 4.

5.

13. The treatment composition according to any one of the preceding claims, wherein when tested according to test method OECD 301B, the shell of the delivery particles degrades by at least 60% within 60 days.

14. The treatment composition according to any one of the preceding claims, wherein the treatment adjuvant is selected from the group consisting of: surfactants, conditioning actives, deposition aids, rheology modifiers or structuring agents, bleaching systems, stabilizers, builders, chelating agents, dye transfer inhibitors, dispersants, enzymes, enzyme stabilizers, catalytic metal complexes, polymeric dispersants, clays and soil release / anti-redeposition agents, optical brighteners, defoamers, silicones, colorants, aesthetic dyes, perfume, additional perfume delivery systems, structuring elastifiers, carriers, hydrotropes, processing aids, anti-caking agents, coatings, formaldehyde scavengers, pigments and mixtures thereof.

15. The treatment composition according to any one of the preceding claims, wherein the treatment adjuvant comprises an anionic surfactant, a cationic conditioner or a mixture thereof.

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