Degradable delivery particles from mixed isocyanates comprising an aromatic moiety and chitosan

Abstract

An improved delivery particle comprising a benefit agent core material and a shell encapsulating the core material is described, along with a process for forming such a delivery particle and articles of manufacture. The shell is a polymeric material that is the reaction product of chitosan derived from an aqueous phase, and a cross-linking agent comprising an isocyanate component comprising a mixture of two or more di- and / or poly-isocyanates derived from an oil phase, the di- and / or poly-isocyanates each comprising at least one aromatic moiety. The delivery particle of the invention has improved release characteristics with lower leakage in matrices and carriers, and with enhanced degradation characteristics in OECD test method 301B

Description

DEGRADABLE DELIVERY PARTICLES FROM MIXED ISOCYANATES COMPRISING AN AROMATIC MOIETY AND CHITOSANCROSS REFERENCE TO RELATED APPLICATIONSJOINT RESEARCH STATEMENT

[0001] Encapsys, LLC and The Procter & Gamble Company executed a Joint Research Agreement on or about July 29, 2021, and this invention was made as a result of activities undertaken within the scope of that Joint Research Agreement between the parties that was in effect on or before the date of this invention.Field of the Invention

[0002] This invention relates to capsule manufacturing processes and biodegradable delivery particles produced by such processes, the delivery particles comprising a core material and a shell encapsulating the core, the shell comprising a reaction product of a cross-linking agent, and a chitosan. The shell is made from chitosan and a cross-linking agent, where the crosslinking agent comprises an isocyanate component, the isocyanate component comprising a mixture of two or more di- and / or poly-isocyanates, derived from an oil phase, the di- and / or poly-isocyanates each containing an aromatic moiety.Description of the Related Art

[0003] Encapsulation also known as microencapsulation is a process where droplets of liquids, particles of solids or gasses are enclosed inside a solid shell and are generally in the micro-size range. The core material is separated from the surrounding environment by the shell. Encapsulation technology has a wide range of commercial applications for different industries. Overall, capsules are capable of one or more of (i) providing stability of a formulation or material via the mechanical separation of incompatible components, (ii) protecting the core material from the surrounding environment, (iii) masking or hiding an undesirable attribute of an active ingredient and (iv) controlling or triggering the release of the active ingredient to a specific time or location. All of these attributes can lead to an increase of the shelf-life of several products and a stabilization of the active ingredient in liquid formulations.

[0004] Various processes for encapsulation, and exemplary methods and materials are set forth in Schwantes (U.S. Pat. No. 6,592,990), Nagai et al. (U.S. Pat. No. 4,708,924), Baker et al. (U.S.Pat. No. 4,166,152), Woiciak (U.S. Pat. No. 4,093,556), Matsukawa et al. (U.S. Pat. No. 3,965,033), Qzono (U.S. Pat. No. 4,588,639), Irgarashi et al. (U.S. Pat. No. 4,610,927), Brown et al. (U.S. Pat. No. 4,552,811), Scher (U.S. Pat. No. 4,285,720), Jahns et al. (U.S. Pat. Nos. 5,596,051 and 5,292,835), Matson (U.S. Pat. No. 3,516,941), Foris et al. (U.S. Pat. Nos. 4,001,140; 4,087,376; 4,089,802 and 4,100,103), Greene et al. (U.S. Pat. Nos. 2,800,458; 2,800,457 and 2,730,456), Clark (U.S. Pat. No. 6,531,156), Hoshi et al. (U.S. Pat. No. 4,221,710), Hayford (U.S. Pat. No. 4,444,699), Hasler et al. (U.S. Pat. No. 5,105,823), Stevens (U.S. Pat. No. 4,197,346), Riecke (U.S. Pat. No. 4,622,267), Greiner et al. (U.S. Pat. No. 4,547,429), and Tice et al. (U.S. Pat. No. 5,407,609), among others and as taught by Herbig in the chapter entitled “Microencapsulation” in Kirk-Othmer Encyclopedia of Chemical Technology, V.16, pages 438-463.

[0005] Core-shell encapsulation is useful to preserve actives, such as benefit agents, in harsh environments and to release them at the desired time, which may be during or after use of goods incorporating the delivery particles. Among various mechanisms that can be used for release of benefit agent from the delivery particles, the one commonly relied upon is mechanical rupture of the capsule shell through friction or pressure. Selection of mechanical rupture as the release mechanism constitutes another challenge to the manufacturer, as rupture must occur at specific desired times, even if the capsules are subject to mechanical stress prior to the desired release time.

[0006] Industrial interest for encapsulation technology has led to the development of several polymeric capsules chemistries which attempt to meet the requirements of biodegradability, low shell permeability, high deposition, targeted mechanical properties and rupture profile. Increased environmental concerns have put the polymeric capsules under scrutiny, therefore manufacturers have started investigating sustainable solutions for the encapsulation of benefit agents.

[0007] Biodegradable materials exist and are able to form delivery particles via coacervation, spray-drying or phase inversion precipitation. However, the delivery particles formed using these materials and techniques are highly porous and not suitable for aqueous compositions containing surfactants or other carrier materials, since the benefit agent is prematurely released to the composition.

[0008] Non-leaky and performing delivery particles in aqueous surfactant-based compositions exist, however due to their chemical nature and cross-linking, they are not biodegradable.

[0009] Encapsulation can be found in areas as diverse as pharmaceuticals, personal care, textiles, food, coatings and agriculture. In addition, the main challenge faced in encapsulation is that a complete retention of the encapsulated active within the capsule is required throughout the whole supply chain, until a controlled or triggered release of the core material is applied. There are significantly limited microencapsulation technologies that can fulfill the rigorous criteria for long-term retention and active protection capability for commercial needs, especially when it comes to encapsulation of small molecules.

[0010] Delivery particles having a shell made at least in part from chitosan-based materials are known. However, such particles may not delivery the desired level of performance. Furthermore, chitosan can be a challenging material to work with due to its viscosity-building tendencies.

[0011] U.S. Patent Publication 2020 / 0252469 discloses treatment of chitosan in an acidic medium prior to the formation of microcapsules, for example by adjusting the pH with hydrochloric acid (HC1). 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, improvements in the performance of delivery particles are still desired.

[0012] Biodegradable capsules are needed that minimize capsule leakage or extend shelf life. During manufacture and / or during shelf storage, leakage into carriers and matrixes can be a function of water level and can even be influenced by surfactants and other adjuvants present in many products, which can lead to premature benefit agent release or leakage. Reduced benefit agent leakage across products such as fabric enhancer, single use unit dosage forms, laundry fragrance beads, spray dried particles, liquid or dry laundry, shampoo would be an advance in the art, enabling more efficient manufacture of consumer and industrial products containing encapsulated benefit agent such as fragrance.

[0013] There continues to be need for improved treatment compositions that include delivery particles made from sustainable materials such as chitosan-based materials. There continues to be need for improved treatment compositions that include delivery particles that successfully retain core contents to be available at desired points in the use cycle of treatment compositions and release the contents when beneficial. There continues to be a need for treatment compositions wherein the benefit agent is retained and stable during shelf storage, with reducedlevels of leakage into carriers and matrices. The compositions of the invention achieve improved retention and stability of the core materials of core-shell delivery particles in the presence of aqueous surfactants and other components of aqueous-based carriers and matrices while efficiently releasing the core at desired touchpoints, and meeting the need for degradability to achieve sustainability and are an advance in the art.Definitions

[0014] For ease of reference in this specification and in the claims, the term “monomer” or “monomers” as used herein with regard to the structural materials that form the wall polymer of the delivery particles is to be understood as monomers, but also is inclusive of oligomers and / or prepolymers formed of the specific monomers.

[0015] As used herein the term “water soluble material” means a material that has a solubility of at least 0.5% wt in water at 60 °C.

[0016] As used herein the term “oil soluble” means a material that has a solubility of at least 0.1 % wt in the core of interest at 50 °C.

[0017] As used herein the term “oil dispersible” means a material that can be dispersed at least 0.1% wt in the core of interest at 50 °C without visible agglomerates.

[0018] As used herein, “deliver}' particles,” “particles,” “encapsulates,” “microcapsules,” and “capsules” are used interchangeably, unless indicated otherwise. As used herein, these terms typically refer to core / shell delivery particles.Summary of the InventionThe invention describes a delivery particle comprising a core material and a shell encapsulating the core material. The core material can comprise a benefit agent. The shell comprises a polymer. More particularly, the invention discloses a composition comprising a population of core-shell encapsulates, the core comprising a benefit agent. The shell is a polymeric material comprising the reaction product of a cross-linking agent from an oil phase, and a chitosan derived from a water phase. The cross-linking agent comprises a mixture of two or more di- and / or poly-isocyanates, derived from the oil phase, the di- and / or poly-isocyanates each containing an aromatic moiety. Surprisingly, it has been found that leakage can be controlled as a function of two isocyanates, each comprising at least one aromatic moiety, which when combined with chitosan yield a low leakage delivery particle in different matrices and carriers, to an extent heretofore unachieved with degradable constructs. More particularly the cross-linking agent comprises an isocyanate component, wherein theisocyanate component comprises a mixture of two or more di- and / or poly-isocyanates, derived from an oil phase, the di- and / or poly-isocyanates each comprising an aromatic moiety; and each isocyanate is independently selected from the group consisting of an alpha aromatic isocyanate and a beta aromatic isocyanate. In embodiments, the mixture of di- and / or poly-isocyanates can comprise at least one alpha isocyanate and at least one beta isocyanate.Enhanced performance in terms of lower leakage and retention of core material in carrier material is surprisingly obtainable wherein the weighted %NCO of the aromatic isocyanate of the isocyanate component is from 15 to 32% or even from 20 to 26%, or even from 20 to 25% by weight, or even from 21 to 25% by weight.

[0019] The isocyanate component has a mass percent of alpha aromatic isocyanate in the range from 20 to 50% by weight, preferably from 25 to 40% by weight, most preferably from 30 to 35% by weight. The balance of the isocyanate component is the beta aromatic isocyanate in the mass percent calculation. Mass percent is understood as the mass fraction expressed as a percentage.

[0020] The invention in addition to the composition, also discloses a method of making the composition which is a population of core-shell delivery particles. The core comprises a benefit agent, and the shell comprises a polymeric material that is the reaction product of a crosslinking agent of at least two isocyanate monomers, oligomers, or prepolymers, and the chitosan, The method of making the composition of the invention comprises the steps of: forming a water phase dissolving or dispersing chitosan in water. Optionally, prior to capsule shell formation, the chitosan can be pretreated with one or more of a redox initiator such as a persulfate or with an acid or acids at a pH of from pH 3 to pH 6.5, or even a pH of from 4 to 6.5 at a temperature of at least 25 °C., for at least one hour or to achieve a viscosity of less than 1500 centipoise (cp) and preferably less than 500 cp, to form a treated chitosan; and, forming an oil phase comprising dissolving together at least one benefit agent and an isocyanate component comprising at least two isocyanates having an aromatic moiety wherein the weighted %NCO of the aromatic isocyanate of the isocyanate component is from 15 to 32% or even from 20 to 26%, or even from 20 to 25% by weight, or even from 21 to 25% by weight; and,forming an emulsion by mixing under high shear agitation the water phase and the oil phase into an excess of the water phase, thereby forming droplets of the oil phase dispersed in the water phase, and optionally adjusting the pH of the emulsion to be in a range from pH 3 to pH 6; and, curing the emulsion by heating to at least 40 °C., for a time sufficient to form a shell at an interface of the droplets with the water phase, the shell comprising the reaction product of the cross-linking component and the chitosan, and the shell surrounding the core comprising the droplets of the oil phase. Optionally the chitosan can be a treated chitosan. The droplets of the oil phase comprise the benefit agent in that the benefit agent is itself an oil or soluble in an added oil or soluble in the cross-linking agent.

[0021] In certain embodiments at least 21 wt % of the shell comprises chitosan. In embodiments, the isocyanate component comprises methylenediphenyl isocyanate and xylylene diisocyanate in a weight ratio of from 1 :2 to 1 : 1.75. In embodiments, the isocyanate component comprises by weight 30 to 40% methylenediphenyl isocyanate and from 60 to 70% xylylene diisocyanate.

[0022] In further constructs, the delivery particles of the invention can be fashioned into new articles by incorporation into various articles of manufacture. Such article can be selected from the group consisting of an agricultural formulation, a slurry encapsulating an agricultural active, a population of dry encapsulates encapsulating an agricultural active, an agricultural formulation encapsulating an insecticide, and an agricultural formulation for delivering a preemergent herbicide. The agricultural active can be selected from the group consisting of an agricultural herbicide, an agricultural pheromone, an agricultural pesticide, an agricultural nutrient, an insect control agent and a plant stimulant.Brief Description of DrawingsFig. 1 f.v a depiction of leakage data of a delivery particle of a combination of two isocyanates comprising an aromatic moiety. Figure 1 depicts leakuge profile oj delivery particles comprising differing concentrations of an alpha aromatic isocyanate in a combination oj alpha isocyanate and beta isocyanate as described in

[0023] Table 1.

[0024] Fig. 2 is a depiction of leakage data of a delivery particle of a combination of two isocyanates comprising an aromatic moiety. Figure 2 depicts leakage profile of delivery particles comprising differing concentrations of %NCO of the aromatic isocyanate of the isocyanate component as described in Table 3.Detailed Description

[0025] The invention describes a delivery particle comprising a core material and a shell encapsulating the core material. The core material can comprise a benefit agent. The shell comprises a polymeric material that is the reaction product of chitosan derived from an aqueous phase, and a cross-linking agent comprising an isocyanate component comprising a mixture of two or more di- and / or poly-isocyanates, derived from an oil phase, the di- and / or poly-isocyanates each comprising an aromatic moiety. The isocyanates are di-isocyanates, triisocyanates or a mixture of di- and tri-isocyanates.

[0026] Controlling leakage into matrices and carriers in the presence of water is challenging. Shelf stability of products in terms of low leakage into the carrier or matrix in the presence of water is important in maintaining the ability to deliver benefit agent such as fragrance at desired touch points. Benefit agent prematurely leaked into matrices or carrier is less available at desired later touchpoints. Encapsulation is used to retain the benefit agent for increased product shelf life. In certain articles of manufacture, such as treatment compositions for fabrics and textiles, it is desirable to retain the benefit agent for expression at later stage touch points such as after the wash, in the dry cycle, or during wearing. Leaked benefit agent is generally not available for desired expression at such later stages, though such expression is highly sought after, yet difficult to achieve successfully. Surprisingly, it has been found that leakage can be controlled as a function of two isocyanates each comprising an aromatic moiety, which when combined with chitosan yield a low leakage delivery particle in different matrices and carriers, to an extent heretofore unachieved with degradable constructs.Low leakage can be achieved with careful selection of a mixture of di- and / or polyisocyanates, comprising alpha or beta isocyanates, especially those combinations comprising at least one alpha isocyanate and at least one beta isocyanate. In embodiments, surprisingly low leakage into carrier material is seen when the weighted %NCO of the aromatic isocyanate of the isocyanate component is from 15 to 32% or even from 20 to 26%, or evenfrom 20 to 25% by weight, or even from 21 to 25% by weight. In particular the compositions of the invention comprise an isocyanate component comprising an alpha and / or beta aromatic isocyanate. The alpha aromatic isocyanate is selected from the group consisting of:andIVwherein R is a biuret, a uretdione, a isocyanurate, a polyol having a pendant urethane group, a polyamine having a urea pendant group, a polyacid with an anhydride group, a poly-isocyanate comprising a biuret, a poly-isocyanate comprising a uretdione, or a polyisocyanate comprising an isocyanurate.R in structures I, II, III and IV and XII and XIII for example comprises moieties with at least two or more functional groups that link into the respective di- or tri-isocyanate. R in structures I, II, III and IV and XII and XIII for example can comprise polyol, or a polyol having one or more pendant urethane groups, or a polyamine, such as a polyamine having one or more urea pendant groups or other linking groups, a polyacid with an anhydride group, a poly-isocyanate comprising a biuret, a poly-isocyanate comprising a uretdione, or a polyisocyanate comprising an isocyanurate. In structures I, II, III and IV and XII and XIII for example the R moieties include at least two or more functional groups that link into the respective di- or tri-isocyanate. R bonds into the above structures I, II, III and IV and XII and XIII respectively, via a linking group which comprises a functional group such as an amine, a hydroxy, an anhydride and similar groups that can bond into the listed structure.The aromatic isocyanates of formulas I-XVI are based on derivative variations of generally commercially available isocyanates such as xylylene diisocyanate (XDI), toluene diisocyanate (TDI) and methylene diphenyl diisocyanates (MDI).The above selected aromatic isocyanates are generally available commercially. For example, Covestro in Leverkusen, Germany is a supplier of polyisocyanates and prepolymers under the Desmodur brand. Polyisocyanates conforming to the structures I-XVI disclosed herein are available under the Desmodur E brand of isocyanates and prepolymers, and / or can also be derived synthetically. Optionally aromatic isocyanates are also commercially available from sources such as Mitsui Chemicals, Inc., Tokyo, Japan such as the Takenate brand of isocyanates, e.g., Takenate D-110N adducts based on xylylene diisocyanate.Specific examples of alpha aromatic isocyanates useful in the invention can be selected from the group consisting of:Vwherein n is an integer from 1 to 24.The beta aromatic isocyanate useful in the invention can be selected from the group consisting of:wherein R is a biuret, a uretdione, a isocyanurate, a polyol having a pendant urethane group, a polyamine having a urea pendant group, a polyacid with an anhydride group, a poly-isocyanate comprising a biuret, a poly-isocyanate comprising a uretdione, a polyisocyanate comprising an isocyanurate.Specific examples of beta aromatic isocyanates useful in the invention can be selected from the group consisting of:The present disclosure relates to treatment compositions that include delivery particles having shells made, at least in part, from chitosan-based materials. In particular, the delivery particles include a shell comprising a reaction product of chitosan and a cross-linking agent.The cross-linking agent comprises an isocyanate component comprising a mixture of two or more di- and / or poly-isocyanates, derived from an oil phase, the di- and / or poly-isocyanates each containing an aromatic moiety. The isocyanate component can comprise at least two di- and / or poly-isocyanates selected from methylene diphenyl diisocyanate and xylylene diisocyanate. In embodiments, the xylylene diisocyanate comprises a trimethylol propaneadduct of xylylene diisocyanate, the methylene diphenyl diisocyanate can be selected from 2,2’-methylenediphenyl diisocyanate and 4,4’-methylenediphenyl diisocyanate. Preferably the isocyanate components are in a weight ratio of from 1:2 to 1: 1.75. Desirably the isocyanate component comprises by weight 30 to 40% of a methylene diphenyl diisocyanate and from 60 to 70% of a xylylene diisocyanate. Usefully, the isocyanate component comprises by weight about 34% methylene diphenyl diisocyanate and about 66% xylylene diisocyanate. Chitosan in combination with the isocyanate component within this isocyanate range or ratio surprisingly is able to efficiently deliver benefit agent at desired touchpoints. Leakage into matrice components and / or carriers is surprisingly reduced as a function of the combination with two isocyanates with the chitosan. The mixture of isocyanates having an aromatic moiety for example can comprise for example trimers of xylylene diisocyanate (XDI) or oligomers or pre-polymers of methylene diphenyl diisocyanate (MDI).

[0027] Optionally, prior to shell formation, the chitosan used to make the particle shells can be treated such with acid, or even a mixture of acids such as describe in US Serial 63429232 filed Dec 1 , 2022, or with a redox initiator preferably persulfate such as described in US Serial 63429240 filed Dec 1, 2022, incorporated herein by reference. The redox initiator is selected from any of persulfate or a peroxide. Preferably, the redox initiator is selected from the group consisting of ammonium persulfate, sodium persulfate, potassium persulfate, cesium persulfate, benzoyl peroxide, hydrogen peroxide, and mixtures thereof.

[0028] Typically, when chitosan is dissolved in water, for example during the process of making delivery particles, the resulting mixture tends to be quite viscous. This can result in flowability and processing challenges, and / or inhibit the adequate formation of delivery particle shells. It has been described in US Serial No. 63429232 that acid treatment can result in a decrease of the mixture’s viscosity and an improved shell structure. Additionally, it is believed that acid treating the chitosan can beneficially affect the molecular weight of the chitosan, thereby leading to improved shell formation and / or delivery performance.

[0029] The delivery particles have shells made, at least in part, from chitosan-based materials. In particular, the delivery particles include a shell comprising a reaction product of chitosan and the isocyanate component.

[0030] Without wishing to be bound by theory, it is believed that careful selection of the chitosan and isocyanate combination within the weight ratios of the invention is advantageous in surprisingly achieving a long shelf-life composition containing delivery particles. For example, selection of an isocyanate component according to the invention result in delivery particles that perform better at certain touchpoints. It is believed that the combination of isocyanates of the invention yields a higher density delivery particle. It is believed that the surprising effect of reduced leakage is attributable to not only density of the polymeric material but also related to the presence of aromatic moieties in combination with the reactive sites of the isocyanate component.

[0031] Furthermore, chitosan tends to present processing challenges, particularly its viscosity, in aqueous environments. The viscosity can affect the flowability of solutions and / or inhibit the adequate formation of particle walls. Optionally treatment with acid can aid in lowering of solution viscosity. Without wishing to be bound by theory, it is believed that careful selection of the chitosan’s molecular weight can be advantageous. For example, selection of a chitosan having a molecular weight above a certain threshold can result in delivery particles that perform better at certain touchpoints compared to particles made from chitosan of a lower molecular weight. Surprisingly treatment with acid can yield achitosan at a 3.5% concentration, typically having a starting viscosity or approximately 4000 cP, displaying a viscosity reduction of 60% or even exceeding 60%, to a viscosity of 1500 cP, or even 1000 cP at the same concentration as compared to an untreated chitosan.

[0032] The invention teaches a composition comprising a core-shell encapsulate, also known as a delivery particle, including a process of making such encapsulates or delivery particles. The core comprises a benefit agent, preferably a perfume, and the shell can comprise for example a polyurea resin polymeric material which is the reaction product of a cross-linking agent comprising a mixture of two or more di- and / or poly- isocyanates derived from an oil phase the di- and / or poly-isocyanates each comprising an aromatic moiety. In forming the composition of the invention, chitosan dissolved or dispersed in an aqueous phase and optionally treated with an acid, preferably at a pH of from 3 to about 6.5. The chitosan is treated with acid at a pH of 6.5 or less, or even less than pH 6.0, or even at a pH of from 3 to 6, or even at a pH of 3.5 to 6, or even at a pH of 4 to 6, or even at a pH of 5 to 6, and a temperature of at least 25 °C. for at least one hour. Typically, this treatment step is measurable as a period to obtain a chitosan solution having a viscosity of 1500 centipoise, or less than 1500 centipoise (cp) and preferably less than 500 cp.

[0033] The chitosan is characterized by a weight average molecular weight of from about 100 to about 80,000 kDa, or even from 100 kDa to about 600 kDa. Preferably, the chitosan is characterized by a weight average molecular weight (Mw) of from about 100 kDa to about 500 kDa, preferably from about 100 kDa to about 400 kDa, more preferably from about 100 kDa to about 300 kDa, even more preferably from about 100 kDa to about 200 kDa. The method used to determine the chitosan’s molecular weight and related parameters is provided in the Test Methods section below and uses gel permeation chromatograph with multi-angle light scatter and refractive index detection (GPC-MALS / RI) techniques. Selecting chitosan having the preferred weight average molecular weight can result in capsules having suitable shell formation and / or desirable processibility. For clarity the chitosan weight average molecular weight is measured prior to treatment, such as with acid and / or redox initiator as herein described.

[0034] The ratio of the isocyanate component cross-linking agent to chitosan, based on weight, is 79:21 to 10:90, or even 2:1 to 1 : 10, or even 1 :1 to 1 :7. In certain embodiments, the isocyanates can be each present in at least 20 mole percent of the total isocyanate component.

[0035] The shell can comprise 1 to 25 percent by weight of the core-shell encapsulate.

[0036] The cross-linking agent of the composition optionally can comprise additional polyisocyanate to the mixture of two or more di- or poly- isocyanates. The additional crosslinking agent can be an aliphatic or aromatic monomer, oligomer or prepolymer, usefully of two or more isocyanate functional groups Additional crosslinking agents of the isocyanate type, for example, can be selected from aromatic toluene diisocyanate and its derivatives used in wall formation for delivery particles, or aliphatic monomer, oligomer or prepolymer, for example, hexamethylene diisocyanate and dimers or trimers thereof, or 3,3,5-trimethyl-5- isocyanatomethyl-l-isocyanato cyclohexane tetramethylene diisocyanate, polyisocyanurate of toluene diisocyanate, a trimethylol propane adduct of toluene diisocyanate, toluene diisocyanate, tetramethylxylidene diisocyanate, naphthalene- 1,5-diisocyanate, phenylene diisocyanate, l,3-diisocyanato-2-methylbenzene, hydrogenated MDI, bis(4- isocyanatocyclohexyl) methane, dicyclohexylmethane-4,4’ -diisocyanate, and oligomers and prepolymers thereof. The additional isocyanates useful in the invention comprise isocyanate monomers, oligomers or prepolymers, or dimers or trimers thereof, having at least two isocyanate groups. Optimal cross-linking can be achieved with isocyanates having at least three functional groups. This listing is illustrative and not intended to be limiting.

[0037] Additional crosslinking agents of the isocyanate type can be formed from adducts of polyisocyanates. An adduct is the product of a molecule with itself and / or with another molecule. In the case of adducts of polyisocyanates with themselves, the isocyanate moieties of the polyisocyanate molecule can react with each other, forming a larger polyisocyanate product containing biuret, uretdione, and / or isocyanurate moieties. In the case of polyol adducts of polyisocyanates, the isocyanate moieties of the polyisocyanate molecule can react with the hydroxyl moieties of a polyol, forming a larger polyisocyanate product containing urethane moieties. In the case of polyamine adducts of polyisocyanates, the isocyanate moieties of the polyisocyanate molecule can react with the amine moieties of a polyamine, forming a larger polyisocyanate product containing urea moieties. In the case of polyacid adducts of polyisocyanates, the isocyanate moieties of the polyisocyanate molecule can react with the carboxylic moieties of a polyacid, forming a larger polyisocyanate product containing anhydride moieties. Where a polyisocyanate is a molecule containing 2 or more isocyanate moieties.

[0038] When formulated according to the teachings of the invention, the shell degrades at least 40% or even at least 60% of its mass after at least 60 days when tested according to test method OECD 301B.

[0039] The core-shell encapsulate has a ratio of core to shell of at least 75:25, or 85:15, or 90: 10, or even up to 99: 1, or even at least 99.5:0.5, on the basis of weight.

[0040] The benefit agent is selected from the group consisting of perfume, fragrance, agricultural active, phase change material, essential oil, lubricant, colorant, preservative, antimicrobial active, antifungal active, herbicide, antiviral active, antiseptic active, antioxidant, biological active, deodorant, emollient, humectant, exfoliant, ultraviolet absorbing agent, corrosion inhibitor, silicone oil, wax, bleach particle, fabric conditioner, malodor reducing agent, dye, optical brightener, antiperspirant active and mixture thereof.

[0041] Unless otherwise noted, all component or composition levels are in reference to the active portion of that component or composition, and are exclusive of impurities, for example, residual solvents or by-products, which may be present in commercially available sources of such components or compositions.Shell

[0042] To create the delivery particle of the invention a water phase is prepared, comprising a water solution or dispersion of an amine-containing natural material having free amino moieties. The amine containing natural material is a bio-based material. Such materials for example include chitosan. The amine-containing natural material is dispersed in water. In thecase of chitosan, the material, in embodiments, can even be hydrolyzed thereby protonating at least a portion of the amine groups and facilitating dissolving in water. Hydrolysis is carried out with heating for a period at an acidic pH such as about 3 to about 6.5, or even about 5 or 5.5.

[0043] The oil phase is prepared by dissolving the isocyanate component in oil at 25 °C. Diluents, for example isopropyl myristate, may be used to adjust the hydrophilicity of the oil phase. The oil phase is then added into the water phase and milled at high speed to obtain a targeted size. The emulsion is then cured in one or more heating steps, such as heating to 40 °C in 30 minutes and holding at 40 °C for 60 minutes. Times and temperatures 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 with the water continuous phase. For example, the emulsion is heated to 85 °C in 60 minutes and then held at 85 °C for 360 minutes to cure the capsules. The slurry is then cooled to room temperature.

[0044] Volume weighted median particle size of delivery particles according to the invention can range from 5 microns to 150 microns, or even from 10 to 50 microns, preferably 15 to 50 microns.

[0045] The cross-linking agent of the invention is a mixture or bi- or poly-functional isocyanates. When referring to useful cross-linking agents reference to polyisocyanate should be understood for purposes hereof as inclusive of isocyanate monomer, isocyanate oligomer, isocyanate prepolymer, or dimer or trimer of an aliphatic or aromatic isocyanate. All such monomers, prepolymers, oligomers, or dimers or trimers of aliphatic or aromatic isocyanates are intended by the term “polyisocyanate” as used herein.

[0046] The capsule shell could also be reinforced using additional co-crosslinkers such as multifunctional amines and / or polyamines such as diethylene triamine (DETA), polyethylene imine, and polyvinyl amine.

[0047] The shell may also be reinforced using additional co-crosslinkers such as multifunctional amines and / or polyamines, such as diethylene triamine (DETA), polyethylene imine, polyvinyl amine, or mixtures thereof. Acrylates may also be used as additional co- crosslinkers, for example to reinforce the shell.

[0048] The polymeric material may be formed in a reaction, where the weight ratio of the chitosan present in the reaction to the cross-linker present in the reaction is from about 1 : 10 to about 1 :0.1. It is believed that selecting desirable ratios of the biopolymer to the cross-linkingagent can provide desired ductility benefits, as well as improved biodegradability. It may be preferred that at least 21 wt % of the shell is comprised of moieties derived from chitosan, preferably from acid-treated chitosan. Chitosan as a percentage by weight of the shell may be from about 21% up to about 95% of the shell. The ratio of chitosan in the water phase as compared to the isocyanate in the oil phase may be, based on weight, from 21:79 to 90:10, or even from 1:2 to 10:1, or even from 1 :1 to 7:1. The shell may comprise chitosan at a level of 21 wt% or even greater, preferably from about 21 wt% to about 90 wt%, or even from 21 wt % to 85 wt%, or even 21 wt% to 75 wt%, or 21 wt% to 55 wt% of the total shell being chitosan. The chitosan of this paragraph may optionally be acid-treated chitosan or treated with a redox initiator such as persulfate or both.

[0049] Chitosan may be added into water in a jacketed reactor and optionally pre-treated with one or both of redox initiator or at a pH from 3 to 6.5, adjusted using an acid (such as one or more of HC1, formic acid or acetic acid). The optional pretreatment step can be accomplished by heating to elevated temperature, such as 85 °C in 60 minutes, and then holding at this temperature from 1 minute to 1440 minutes or longer. The water phase then may be cooled to 25 °C. Optionally, a deacetylating step may be added to further facilitate or enhance depolymerization or deacetylation of the chitosan such as by enzymes. An oil phase is prepared by dissolving a mixture of isocyanates, comprising an aromatic moiety, in oil at 25 °C. Diluents, for example isopropyl myristate, may be used to adjust the hydrophobicity of the oil phase. The oil phase may then be added into the water phase and milled at high speed to obtain a targeted size. The emulsion may then 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. Times and temperatures 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 with the water continuous phase. For example, the emulsion may be heated to 85 °C in 60 minutes and then held at 85 °C for 360 minutes to cure the particles. The slurry may then be cooled to room temperature.

[0050] The shell may degrade at least 50% after 20 days (or less) when tested according to test method OECD 301B. The shell may degrade at least 60% of its mass after 60 days (or less) when tested according to test method OECD 301B. The shell may preferably degrade at least 60% of its mass after 60 days (or less) when tested according to test method OECD 301B. The shell may degrade from 30-100%, preferably 40-100%, 50-100%, 60-100%, or 60-95%, in 60 days, preferably 50 days, more preferably 40 days, more preferably 28 days, more preferably 14 days.

[0051] The delivery particles of the present disclosure include a core. The core comprises a benefit agent. The core optionally comprises a partitioning modifier.

[0052] The core of a particle is surrounded by the shell. When the shell is ruptured, the benefit agent in the core is released. Additionally, or alternatively, the benefit agent in the core may diffuse out of the particle, and / or it may be squeezed out. Suitable benefit agents located in the core may include benefit agents that provide benefits to a surface.Core

[0053] The core may comprise from about 5% to about 100%, by weight of the core, of a benefit agent, which may preferably comprise a fragrance. The core may comprise from about 45% to about 95%, preferably from about 50% to about 80%, more preferably from about 50% to about 70%, by weight of the core, of the benefit agent, which may preferably comprise a fragrance.

[0054] The benefit agent may comprise an aldehyde-comprising benefit agent, a ketone- comprising benefit agent, or a combination thereof. Such benefit agents, such as aldehyde- or ketone-containing perfume raw materials, are known to provide preferred benefits, such as freshness benefits. The benefit agent may comprise at least about 20%, preferably at least about 25%, more preferably at least about 40%, even more preferably at least about 50%, by weight of the benefit agent, of aldehyde-containing benefit agents, ketone-containing benefit agents, or combinations thereof.

[0055] The benefit agent may be a hydrophobic benefit agent. Such agents are compatible with the oil phases that are common in making the delivery particles of the present disclosure.

[0056] The benefit agent in the core preferably comprises fragrance material (or simply “fragrance”), which may include one or more perfume raw materials. Fragrance is particularly suitable for encapsulation in the presently described delivery particles, as the fragrancecontaining particles can provide freshness benefits across multiple touchpoints.

[0057] The term “perfume raw material” (or “PRM”) as used herein refers to compounds having a molecular weight of at least about 100 g / mol and which are useful in imparting an odor, fragrance, essence or scent, either alone or with other perfume raw materials. Typical PRMs comprise inter alia alcohols, ketones, aldehydes, esters, ethers, nitrites and alkenes, such as terpene. A listing of common PRMs can be found in various reference sources, for example, “Perfume and Flavor Chemicals”, Vols. 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).

[0058] The PRMs may be characterized by their boiling points (B.P.) measured at the normal pressure (760 mm Hg), and their octanol / water partitioning coefficient (P), which may be described in terms of logP, determined according to the test method below. Based on these characteristics, the PRMs may be categorized as Quadrant I, Quadrant II, Quadrant III, or Quadrant IV perfumes, as described in more detail in U.S. Patent 6,869,923. Suitable Quadrant I, II, III, and IV perfume raw materials are disclosed therein.

[0059] Perfume raw materials having a boiling point B.P. lower than about 250 °C and a logP lower than about 3 are known as Quadrant I perfume raw materials. Quadrant I perfume raw materials are preferably limited to less than 30% of the fragrance material.

[0060] The fragrance may comprise perfume raw materials that have a logP of from about 2.5 to about 4. It is understood that other perfume raw materials may also be present in the fragrance.

[0061] The delivery particles of the present teaching include a benefit agent which comprises one or more ingredients that are intended to be encapsulated. The benefit agent is selected from a number of different materials such as chromogens and dyes, flavorants, perfumes, sweeteners, fragrances, oils, fats, pigments, cleaning oils, pharmaceuticals, pharmaceutical oils, perfume oils, mold inhibitors, antimicrobial agents, fungicides, bactericides, disinfectants, adhesives, phase change materials, scents, fertilizers, nutrients, and herbicides: by way of illustration and without limitation. The benefit agent and oil comprise the core. The core can be a liquid or a solid. With cores that are solid at ambient temperatures, the wall material can usefully enwrap less than the entire core for certain applications where availability of, for example, an agglomerate core is desired on application. Such uses can include scent release, cleaning compositions, emollients, cosmetic delivery and the like. Where the encapsulate core is phase change material, uses can include such encapsulated materials in mattresses, pillows, bedding, textiles, sporting equipment, medical devices, building products, construction products, HVAC, renewable energy, clothing, athletic surfaces, electronics, automotive, aviation, shoes, beauty care, laundry, and solar energy.

[0062] The core constitutes the material encapsulated by the delivery particles. Typically, particularly when the core material is a liquid material, the core material is combined with one or more of the compositions from which the internal wall of the delivery particles is formed or solvent for the benefit agent or partitioning modifier. If the core material can function as theoil solvent in the capsules, e.g., acts as the solvent or carrier for either the wall forming materials or benefit agent, it is possible to make the core material the major material encapsulated, or if the carrier itself is the benefit agent, can be the total material encapsulated. Usually however, the benefit agent is from 0.01 to 99 weight percent of the capsule internal contents, preferably 0.01 to about 65 by weight of the capsule internal contents, and more preferably from 0.1 to about 45% by weight of the capsule internal contents. With certain applications, the core material can be effective even at just trace quantities.

[0063] Where the benefit agent is not itself sufficient to serve as the oil phase or solvent, particularly for the wall forming materials, the oil phase can comprise a suitable carrier and / or solvent, i.e., an added oil. In this sense, the oil is optional, as the benefit agent itself can at times be the oil. These carriers or solvents are generally an oil, preferably have a boiling point greater than about 80 °C. and low volatility and are non-flammable. Though not limited thereto, they preferably comprise one or more esters, preferably with chain lengths of up to 18 carbon atoms or even up to 42 carbon atoms and / or triglycerides such as the esters of C6 to C12 fatty acids and glycerol. Exemplary carriers and solvents include, but are not limited to: ethyldiphenylmethane; isopropyl diphenylethane; butyl biphenyl ethane; benzylxylene; alkyl biphenyls such as propylbiphenyl and butylbiphenyl; dialkyl phthalates e.g. dibutyl phthalate, dioctylphthalate, dinonyl phthalate and ditridecylphthalate; 2,2,4-trimethyl-l,3-pentanediol diisobutyrate; alkyl benzenes such as dodecyl benzene; alkyl or aralkyl benzoates such as benzyl benzoate; diaryl ethers; di(aralkyl)ethers and aryl aralkyl ethers; ethers such as diphenyl ether, dibenzyl ether and phenyl benzyl ether; liquid higher alkyl ketones (having at least 9 carbon atoms); alkyl or aralkyl benzoates, e.g., benzyl benzoate; alkylated naphthalenes such as dipropylnaphthalene; partially hydrogenated terphenyls; high-boiling straight or branched chain hydrocarbons; alkaryl hydrocarbons such as toluene; vegetable and other crop oils such as canola oil, soybean oil, corn oil, sunflower oil, cottonseed oil, lemon oil, olive oil and pine oil; methyl esters of fatty acids derived from transesterification of vegetable and other crop oils, methyl ester of oleic acid, esters of vegetable oil, e.g. soybean methyl ester, straight chain paraffinic aliphatic hydrocarbons, and mixtures of the foregoing.

[0064] Useful benefit agents include perfume raw materials, such as alcohols, ketones, aldehydes, esters, ethers, nitriles, alkenes, fragrances, fragrance solubilizers, essential oils, phase change materials, lubricants, colorants, cooling agents, preservatives, antimicrobial or antifungal actives, herbicides, antiviral actives, antiseptic actives, antioxidants, biological actives, deodorants, emollients, humectants, exfoliants, ultraviolet absorbing agents, self- healing compositions, corrosion inhibitors, sunscreens, silicone oils, waxes, hydrocarbons, higher fatty acids, essential oils, lipids, skin coolants, vitamins, sunscreens, antioxidants,glycerine, catalysts, bleach particles, silicon dioxide particles, malodor reducing agents, dyes, brighteners, antibacterial actives, antiperspirant actives, cationic polymers and mixtures thereof. Phase change materials useful as benefit agents can include, by way of illustration and not limitation, paraffinic hydrocarbons having 13 to 28 carbon atoms, various hydrocarbons such n-octacosane, n-heptacosane, n-hexacosane, n-pentacosane, n-tetracosane, n-tricosane, n- docosane, n-heneicosane, n-eicosane, n-nonadecane, octadecane, n-heptadecane, n- hexadecane, n-pentadecane, n-tetradecane, n-tridecane. Phase change materials can alternatively, optionally in addition include crystalline materials such as 2,2-dimethyl-l,3- propanediol, 2-hydroxymethyl-2-methyl-l, 3-propanediol, acids of straight or branched chain hydrocarbons such as eicosanoic acid and esters such as methyl palmitate, fatty alcohols and mixtures thereof.

[0065] Preferably, in the case of fragrances, a perfume oil acts as benefit agent and solvent for the wall forming material, as illustrated in the examples herein.

[0066] Optionally the water phase may include an emulsifier. Non-limiting examples of emulsifiers include water-soluble salts of alkyl sulfates, alkyl ether sulfates, alkyl isothionates, alkyl carboxylates, alkyl sulfosuccinates, alkyl succinamates, alkyl sulfate salts such as sodium dodecyl sulfate, alkyl sarcosinates, alkyl derivatives of protein hydrolyzates, acyl aspartates, alkyl or alkyl ether or alkylaryl ether phosphate esters, sodium dodecyl sulphate, phospholipids or lecithin, or soaps, sodium, potassium or ammonium stearate, oleate or palmitate, alkylarylsulfonic acid salts such as sodium dodecylbenzenesulfonate, sodium dialkylsulfosuccinates, dioctyl sulfosuccinate, sodium dilaurylsulfosuccinate, poly(styrene sulfonate) sodium salt, isobutylene-maleic anhydride copolymer, gum arabic, sodium alginate, carboxymethylcellulose, cellulose sulfate and pectin, poly(styrene sulfonate), isobutylenemaleic anhydride copolymer, carrageenan, sodium alginate, pectic acid, tragacanth gum, almond gum and agar; semi-synthetic polymers such as carboxymethyl cellulose, sulfated cellulose, sulfated methylcellulose, carboxymethyl starch, phosphated starch, lignin sulfonic acid; and synthetic polymers such as maleic anhydride copolymers (including hydrolyzates thereof), polyacrylic acid, polymethacrylic acid, acrylic acid butyl acrylate copolymer or crotonic acid homopolymers and copolymers, vinyl benzenesulfonic acid or 2-acrylamido-2- methylpropanesulfonic acid homopolymers and copolymers, and partial amide or partial ester of such polymers and copolymers, carboxy modified polyvinyl alcohol, sulfonic acid-modified polyvinyl alcohol and phosphoric acid-modified polyvinyl alcohol, phosphated or sulfated tristyrylphenol ethoxylates, palmitamidopropyltrimonium chloride (Varisoft PATC™, available from Degussa Evonik, Essen, Germany), distearyl dimonium chloride, cetyltrimethylammonium chloride, quaternary ammonium compounds, fatty amines, aliphaticammonium halides, alkyldimethylbenzylammonium halides, alkyldimethylethylammonium halides, polyethyleneimine, poly(2-dimethylamino)ethyl methacrylate) methyl chloride quaternary salt, poly(l-vinylpyrrolidone-co-2-dimethylaminoethyl methacrylate), poly(acrylamide-co-diallyldimethylammonium chloride), poly(allylamine), poly[bis(2- chloroethyl) ether-alt-l,3-bis[3-(dimethylamino)propyl]urea] quatemized, and poly(dimethylamine-co-epichlorohydrin-co-ethylenediamine), condensation products of aliphatic amines with alkylene oxide, quaternary ammonium compounds with a long-chain aliphatic radical, e.g. distearyldiammonium chloride, and fatty amines, alkyldimethylbenzylammonium halides, alkyldimethylethylammonium halides, polyalkylene glycol ether, condensation products of alkyl phenols, aliphatic alcohols, or fatty acids with alkylene oxide, ethoxylated alkyl phenols, ethoxylated aryl phenols, ethoxylated polyaryl phenols, carboxylic esters solubilized with a polyol, polyvinyl alcohol, polyvinyl acetate, or copolymers of polyvinyl alcohol polyvinyl acetate, polyacrylamide, poly(N- isopropylacrylamide), poly(2 -hydroxypropyl methacrylate), poly(-ethyl-2-oxazoline), poly(2- isopropenyl-2-oxazoline-co-methyl methacrylate), poly(methyl vinyl ether), and polyvinyl alcohol-co-ethylene), and cocoamidopropyl betaine. Emulsifier, if employed, is typically from about 0.1 to 40% by weight, preferably 0.2 to about 15% by weight, more typically 0.5 to 10% be weight, based on total weight of the formulation.100671 The delivery particles may encapsulate a partitioning modifier in addition to the benefit agent. Non-limiting examples of partitioning modifiers include isopropyl myristate, mono-, di- , and tri-esters of C4-C24 fatty acids, castor oil, mineral oil, soybean oil, hexadecanoic acid, methyl ester isododecane, isoparaffin oil, polydimethylsiloxane, brominated vegetable oil, and combinations thereof. Delivery particles may also have varying ratios of the partitioning modifier to the benefit agent so as to make different populations of delivery particles that may have different bloom patterns. Such populations may also incorporate different perfume oils so as to make populations of delivery particles that display different bloom patterns and different scent experiences. Patent publication US 2011-0268802 discloses other non-limiting examples of delivery particles and partitioning modifiers and is hereby incorporated by reference.

[0068] Optionally, if desired, the delivery particles can be dewatered such as through decanting, filtration, centrifuging or other separation technique. Alternatively, the aqueous slurry delivery particles can be spray dried.

[0069] In some examples of the process and compositions, the delivery particles may consist of one or more distinct populations. The composition may have at least two different populations of delivery particles that vary in the exact make-up of the perfume oil and in themedian particle size and / or partitioning modifier to perfume oil (PM:PO) weight ratio. In some examples, the composition includes more than two distinct populations that vary in the exact make up the perfume oil and in their fracture strengths. In some further examples, the populations of delivery particles can vary with respect to the weight ratio of the partitioning modifier to the perfume oil(s). In some examples, the composition can include a first population of delivery particles having a first ratio that is a weight ratio of from 2:3 to 3:2 of the partitioning modifier to a first perfume oil and a second population of delivery particles having a second ratio that is a weight ratio of less than 2:3 but greater than 0 of the partitioning modifier to a second perfume oil.

[0070] In some embodiments, each distinct population of delivery particles is preparable in a distinct slurry. For example, the first population of delivery particles can he contained in a first slurry and the second population of delivery particles contained in a second slurry. It is to be appreciated that the number of distinct slurries for combination is without limit and a choice of the formulator such that 3, 10, or 15 distinct slurries may be combined. The first and second populations of delivery particles may vary in the exact make-up of the benefit agent, such as the perfume oil, and in the median particle size and / or PM:PO weight ratio.

[0071] In some embodiments, the composition, can be prepared by combining the first and second slurries with at least one adjunct ingredient and optionally packaged in a container. In some examples, the first and second populations of delivery particles can be prepared in distinct slurries and then spray dried to form a particulate. The distinct slurries may be combined before spray drying, or spray dried individually and then combined together when in particulate powder form. Once in powder form, the first and second populations of delivery particles may be combined with an adjunct ingredient to form the composition useful as a feedstock for manufacture of consumer, industrial, medical or other goods. In some examples, at least one population of delivery particles is spray dried and combined with a slurry of a second population of delivery particles. In some examples, at least one population of delivery particles is dried, prepared by spray drying, fluid bed drying, tray drying, or other such drying processes that are available.

[0072] In some examples, the slurry or dry particulates can include one or more adjunct materials such as processing aids selected from the group consisting of a carrier, an aggregate inhibiting material, a deposition aid, a particle suspending polymer, and mixtures thereof. Nonlimiting examples of aggregate inhibiting materials include salts that can have a chargeshielding effect around the particle, such as magnesium chloride, calcium chloride, magnesium bromide, magnesium sulfate, and mixtures thereof. Non-limiting examples of particlesuspending polymers include polymers such as xanthan gum, carrageenan gum, guar gum, shellac, alginates, chitosan; cellulosic materials such as carboxymethyl cellulose, hydroxypropyl methyl cellulose, cationically charged cellulosic materials; polyacrylic acid; polyvinyl alcohol; hydrogenated castor oil; ethylene glycol distearate; and mixtures thereof.

[0073] In some embodiments, the slurry can include one or more processing aids, selected from the group consisting of water, aggregate inhibiting materials such as divalent salts; particle suspending polymers such as xanthan gum, guar gum, carboxy methyl cellulose.

[0074] In other examples of the invention, the slurry can include 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; nonpolar solvents, including but not limited to, mineral oil, perfume raw materials, silicone oils, hydrocarbon paraffin oils, and mixtures thereof.

[0075] In some examples, said slurry may include a deposition aid that may comprise a polymer selected from the group comprising: polysaccharides, in one aspect, cationically modified starch and / or cationically modified guar; polysiloxanes; poly diallyl dimethyl ammonium halides; copolymers of poly diallyl dimethyl ammonium chloride and polyvinyl pyrrolidone; a composition comprising polyethylene glycol and polyvinyl pyrrolidone; acrylamides; imidazoles; imidazolinium halides; polyvinyl amine; copolymers of poly vinyl amine and N-vinyl formamide; polyvinyl formamide, polyvinyl alcohol; polyvinyl alcohol crosslinked with boric acid; polyacrylic acid; polyglycerol ether silicone cross-poly mers; polyacrylic acids, polyacrylates, copolymers of polyvinylamine and polvyinylalcohol oligomers of amines, in one aspect a diethylenetriamine, ethylene diamine, bis(3- aminopropyljpiperazine, N,N-Bis-(3-aminopropyl)methylamine, tris(2-aminoethyl)amine and mixtures thereof; polyethyleneimine, a derivatized polyethyleneimine, in one aspect an ethoxylated polyethyleneimine; a polymeric compound comprising, at least two moieties selected from the moieties consisting of a carboxylic acid moiety, an amine moiety, a hydroxyl moiety, and a nitrile moiety on a backbone of polybutadiene , polyisoprene, polybutadiene / styrene, polybutadiene / acrylonitrile, carboxyl- terminated polybutadiene / acrylonitrile or combinations thereof; pre-formed coacervates of anionic surfactants combined with cationic polymers; polyamines and mixtures thereof.

[0076] In some additional examples to illustrate the invention, at least one population of delivery particles can be contained in an agglomerate and then combined with a distinct population of deliver}' particles and at least one adjunct material. Said agglomerate maycomprise materials selected from the group consisting of silicas, citric acid, sodium carbonate, sodium sulfate, sodium chloride, and binders such as sodium silicates, modified celluloses, polyethylene glycols, polyacrylates, polyacrylic acids, zeolites and mixtures thereof.

[0077] Suitable equipment for use in the processes disclosed herein may include continuous stirred tank reactors, homogenizers, turbine agitators, recirculating pumps, paddle mixers, plough shear mixers, ribbon blenders, vertical axis granulators and drum mixers, both in batch and, where available, in continuous process configurations, spray dryers, and extruders. Such equipment can be obtained 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.).Water soluble unit dose article

[0078] Water-soluble unit dose articles, often referred to as a single use unit dose “SUD” comprises a water-soluble film, preferably a polyvinyl alcohol film and a laundry detergent composition, wherein the water-soluble film encloses the laundry detergent composition. The laundry detergent composition comprises capsules. The term “capsules” is inclusive or interchangeable with terms such as “delivery particles,” “particles,” “encapsulates,” and “microcapsules”. It was found that when formulated into water-soluble unit dose articles comprising a detergent composition enclosed into a water-soluble film, there was lower than desired consumer noticeable freshness benefits on fabrics following a wash operation. Encapsulates is unit does articles and / or in laundry detergent compositions have been found to leak perfume when formulated in surfactant comprising formulations, especially when formulated in low water surfactant comprising formulations. Perfume leakage can compromise freshness delivery onto fabrics, as well as potentially causing some product discoloration when perfume raw materials react with other components formulated in the detergent formulation such as amines. The present invention provide perfume encapsulates with reduced petrochemically derived content that are less sensitive to leakage when formulated within a low water surfactant comprising detergent formulation, and which are capable of providing improved freshness benefits on fabrics during and after the wash operation when formulated in a water-soluble unit dose detergent composition enclosed in a water-soluble film. The invention also achieves lower leakage when encapsulates according to the invention are dispersed in laundry detergent compositions and / or unit dosage articles. In embodiments a dried encapsulate is also described.

[0079] Water-soluble unit dose articles comprise a water-soluble film, preferably a water- soluble polyvinyl alcohol film, shaped such that the unit-dose article comprises at least one internal compartment surrounded by the water-soluble film. The unit dose article may comprise a first water-soluble film and a second water-soluble film sealed to one another such to define the internal compartment. The water-soluble unit dose article is constructed such that the detergent composition does not leak out of the compartment during storage. However, upon addition of the water-soluble unit dose article to water, the water-soluble film dissolves and releases the contents of the internal compartment into the wash liquor.

[0080] The compartment should be understood as meaning a closed internal space within the unit dose article, which holds the detergent composition. During manufacture, a first water- soluble film may be shaped to comprise an open compartment into which the detergent composition is added. A second water-soluble film is then laid over the first film in such an orientation as to close the opening of the compartment. The first and second films are then sealed together along a seal region.

[0081] The film of the water-soluble unit dose articles is soluble or dispersible in water. The water-soluble film preferably has a thickness of from 20 to 150 micron, preferably 35 to 125 micron, even more preferably 50 to 110 micron, most preferably about 76 micron.

[0082] Preferably, the film has a water- solubility of at least 50%, preferably at least 75% or even at least 95%, as measured by the method set out here after using a glass-filter with a maximum pore size of 20 microns:

[0083] 5 grams > 0.1 gram of film material is added in a pre-weighed 3L beaker and 2L * 5ml of distilled water is added. This is stirred vigorously on a magnetic stirrer, Labline model No. 1250 or equivalent and 5 cm magnetic stirrer, set at 600 rpm, for 30 minutes at 30oC. Then, the mixture is filtered through a folded qualitative sintered-glass filter with a pore size as defined above (max. 20 micron). The water is dried off from the collected filtrate by any conventional method, and the weight of the remaining material is determined (which is the dissolved or dispersed fraction). Then, the percentage solubility or dispersability can be calculated.

[0084] Laundry detergent composition

[0085] The laundry detergent composition may be any suitable composition. The composition may be in the form of a solid, a liquid, or a mixture thereof.

[0086] A solid can be in the form of free-flowing particulates, compacted solids or a mixture thereof. It should be understood, that a solid may comprise some water, but is essentially free of water. In other words, no water is intentionally added other than what comes from the addition of various raw materials.

[0087] In relation to the laundry detergent composition of the present invention, the term ‘liquid’ encompasses forms such as dispersions, gels, pastes and the like. The liquid composition may also include gases in suitably subdivided form. The term ‘liquid laundry detergent composition’ refers to any laundry detergent composition comprising a liquid capable of wetting and treating fabric e.g., cleaning clothing in a domestic washing machine. A dispersion for example is a liquid comprising solid or particulate matter contained therein.

[0088] The laundry detergent composition can be used as a fully formulated consumer product, or may be added to one or more further ingredient to form a fully formulated consumer product. The laundry detergent composition may be a ‘pre-treat’ composition which is added to a fabric, preferably a fabric stain, ahead of the fabric being added to a wash liquor.

[0089] The laundry detergent composition comprises capsules or encapsualtes and said capsules are described in more detail in this specification.

[0090] Preferably, the laundry detergent composition comprises a non-soap surfactant. The non-soap surfactant is preferably selected from non-soap anionic surfactant, non-ionic surfactant or a mixture thereof. Preferably, the laundry detergent composition comprises between 10% and 60%, more preferably between 20% and 55% by weight of the laundry detergent composition of the non-soap surfactant.

[0091] Preferably, the anionic non-soap surfactant comprises linear alkylbenzene sulphonate, alkyl sulphate, alkoxylated alkyl sulphate, or a mixture thereof. Preferably, the alkoxylated alkyl sulphate is an ethoxylated alkyl sulphate.

[0092] Preferably, the laundry detergent composition comprises between 5% and 60%, preferably between 15% and 55%, more preferably between 25% and 50%, most preferably between 30% and 45% by weight of the detergent composition of the non-soap anionic surfactant.

[0093] Preferably, the non-soap anionic surfactant comprises linear alkylbenzene sulphonate and alkoxylated alkyl sulphate, wherein the ratio of linear alkylbenzene sulphonate to alkoxylated alkyl sulphate preferably the weight ratio of linear alkylbenzene sulphonate to ethoxylated alkyl sulphate is from l: 10 to 10: 1, preferably from 6: 1 to 1:6, more preferably from 4:1 to 1 :4, even more preferably from 4:1 to 1: 1. Alternatively the weight ratio of linear alkylbenzene sulphonate to ethoxylated alkyl sulphate is from 1:2 to 1 :4. The alkoxylated alkyl sulphate can be derived from a synthetic alcohol or a natural alcohol, or from a blend thereof, pending the desired average alkyl carbon chain length and average degree of branching. Preferably, the synthetic alcohol is made following the Ziegler process, OXO-process, modified OXO-process, the Fischer Tropsch process, Guerbetprocess or a mixture thereof. Preferably, the naturally derived alcohol is derived from natural oils, preferably coconut oil, palm kernel oil or a mixture thereof.

[0094] Preferably, the laundry detergent composition comprises between 0% and 30%, preferably between 1% and 25%, more preferably between 3% and 20%, most preferably between 5% and 20% by weight of the laundry detergent composition of a non- ionic surfactant. Preferably the weight ratio of non-soap anionic surfactant to nonionic surfactant is from 1:2 to 20: 1, from 1 : 1.5 to 15:1, from 1: 1 to 10:1, or from 1.5: 1 to 5: 1. The non-ionic surfactant is preferably selected from alcohol alkoxylate non-ionic surfactant, including naturally derived alcohol, synthetic derived alcohol based alcohol alkoxylate non-ionic surfactants, and mixtures thereof, pending the desired average alkyl carbon chain length and average degree of branching. The alcohol alkoxylate nonionic surfactant can be a primary or a secondary alcohol alkoxylate nonionic surfactant, preferably a primary alcohol alkoxylate nonionic surfactant. Synthetically derived alcohol alkoxylate non-ionic surfactants include Ziegler-synthesized alcohol alkoxylate, an oxo-synthesized alcohol alkoxylate, a modified oxo-process synthesized alcohol alkoxylate, Fischer-Tropsch synthesized alcohol alkoxylates, Guerbet alcohol alkoxylates, alkyl phenol alcohol alkoxylates, or a mixture thereof. The alkoxylation chain can be a mixed alkoxylation chain comprising ethoxy, propoxy and / or butoxy units, or can be a purely ethoxylated alkyl chain, preferably a purely ethoxylated alkyl chain.

[0095] Preferably, the laundry preferably liquid laundry detergent composition comprises between 1% and 20%, more preferably between 2% and 15%, even more preferably between 3% and 10%, most preferably between 4% and 8% by weight of the laundry detergent composition of soap, preferably a fatty acid salt, more preferably an amine neutralized fatty acid salt, wherein preferably the amine is an alkanolamine more preferably selected from monoethanolamine, diethanolamine, triethanolamine or a mixture thereof, more preferably monoethanolamine.

[0096] Preferably, the laundry detergent composition comprises a non-aqueous solvent, preferably wherein the non-aqueous solvent is selected from ethanol, 1 ,2-propanediol, dipropylene glycol, tripropyleneglycol, glycerol, sorbitol, ethyleneglycol, polyethylene glycol, polypropylene glycol, or a mixture thereof, preferably wherein the polypropyleneglycol has a molecular weight of 400. Preferably the liquid laundry detergent composition comprises between 10% and 40%, preferably between 15% and 30% by weight of the liquid laundry detergent composition of the non-aqueous solvent. Without wishing to be bound by theory the non-aqueous solvents ensure appropriate levels of film plasticization so the film is not too brittle and not too ‘floppy’ . Without wishing to be boundby theory, having the correct degree of plasticization will also facilitate film dissolution when exposed to water during the wash process.

[0097] Preferably, the liquid laundry detergent composition comprises between 1% and 20%, preferably between 5% and 15% by weight of the liquid laundry detergent composition of water.

[0098] Preferably, the laundry detergent composition comprises an ingredient selected from the list comprising cationic polymers, polyester terephthalate polymers, amphiphilic graft co-polymers, alkoxylated preferably ethoxylated polyethyleneimine polymers, carboxymethylcellulose, enzymes, bleach or a mixture thereof.

[0099] The laundry detergent composition can comprise encapsulates and can comprise nonencapsulated perfume.

[0100] The laundry detergent composition may comprise an adjunct ingredient, wherein the adjunct ingredient is selected from hueing dyes, aesthetic dyes, builders preferably citric acid, chelants, cleaning polymers, dispersants, dye transfer inhibitor polymers, fluorescent whitening agent, opacifier, antifoam, preservatives, anti-oxidants, or a mixture thereof. Preferably the chelant is selected from aminocarboxylate chelants, aminophosphonate chelants, or a mixture thereof.

[0101] Preferably, the laundry detergent composition has a pH between 6 and 10, more preferably between 6.5 and 8.9, most preferably between 7 and 8, wherein the pH of the laundry detergent composition is measured as a 10% dilution in demineralized water at 20°C.

[0102] The liquid laundry detergent composition may be Newtonian or non-Newtonian. Preferably, the liquid laundry detergent composition is non-Newtonian. Without wishing to be bound by theory, a non-Newtonian liquid has properties that differ from those of a Newtonian liquid, more specifically, the viscosity of non-Newtonian liquids is dependent on shear rate, while a Newtonian liquid has a constant viscosity independent of the applied shear rate. The decreased viscosity upon shear application for non-Newtonian liquids is thought to further facilitate liquid detergent dissolution. The liquid laundry detergent composition described herein can have any suitable viscosity depending on factors such as formulated ingredients and purpose of the composition. When Newtonian the composition may have a viscosity value, at a shear rate of 20s-l and a temperature of 20°C, of 100 to 3,000 cP, alternatively 200 to 2,000 cP, alternatively 300 to 1,000 cP, following the method described herein. When non-Newtonian, the composition may have a high shear viscosity value, at a shear rate of 20s- 1 and a temperature of 20°C, of 100 to 3,000 cP, alternatively 300 to 2,000 cP, alternatively 500 to 1,000 cP, and a low shear viscosity value, at a shear rate of 1 s-1 and a temperature of 20°C, of 500 to 100,000 cP, alternatively 1000 to 10,000cP, alternatively 1,300 to 5,000 cP, following the method described herein. Methods to measure viscosity are known in the art. According to the present disclosure, viscosity measurements are carried out using a rotational rheometer e.g. TA instruments AR550. The instrument includes a 40mm 2° or 10cone fixture with a gap of around 50-60ptr| for isotropic liquids, or a 40mm flat steel plate with a gap of 1000 ptq for particles containing liquids. The measurement is carried out using a flow procedure that contains a conditioning step, a peak hold and a continuous ramp step. The conditioning step involves the setting of the measurement temperature at 20°C, a pre-shear of 10 seconds at a shear rate of 10s 1 , and an equilibration of 60 seconds at the selected temperature. The peak hold involves applying a shear rate of 0.05sl at 20°C for 3min with sampling every 10s. The continuous ramp step is performed at a shear rate from 0.1 to 1200s 1 for 3min at 20°C to obtain the full flow profile.

[0103] Preferred film materials are preferably polymeric materials. The film material can, for example, be obtained by casting, blow-moulding, extrusion or blown extrusion of the polymeric material, as known in the art.

[0104] The water-soluble film preferably comprises polyvinyl alcohol. Preferably, the water- soluble film comprises at least 50%, preferably at least 60%, by weight of the water-soluble film of polyvinyl alcohol. The water-soluble film may comprise between 50% and 100%, or even between 60% and 99%, by weight of the water-soluble film of polyvinyl alcohol.

[0105] Preferably, the water-soluble film comprises a polyvinyl alcohol selected from a polyvinyl alcohol homopolymer or a polyvinyl alcohol copolymer, or a blend thereof, preferably a blend of polyvinylalcohol homopolymers and / or polyvinylalcohol copolymers, preferably wherein the polyvinyl alcohol copolymers are selected from sulphonated and carboxylated anionic polyvinylalcohol copolymers especially carboxylated anionic polyvinylalcohol copolymers, most preferably wherein the polyvinyl alcohol comprises a blend of a polyvinylalcohol homopolymer and a carboxylated anionic polyvinylalcohol copolymer, or a blend of polyvinyl alcohol homopolymers. Alternatively, the water-soluble film comprises a single carboxylated polyvinyl alcohol copolymer.

[0106] Preferred films exhibit good dissolution in cold water, meaning unheated distilled water. Preferably such films exhibit good dissolution at temperatures of 24oC, even more preferably at lOoC. By good dissolution it is meant that the film exhibits watersolubility of at least 50%, preferably at least 75% or even at least 95%, as measured by the method set out here after using a glass-filter with a maximum pore size of 20 microns, described above.

[0107] Preferred films are those supplied by Monosol under the trade references M8630,M8900, M8779, M8310.

[0108] The film may be opaque, transparent or translucent. The film may comprise a printed area.Delivery particles

[0109] The laundry detergent composition comprises capsules (delivery particles), wherein the capsules have a core and a shell and wherein the shell surrounds the core.

[0110] The laundry detergent composition preferably comprises the capsules in an amount from 0.05% to 20%, more preferably from 0.05% to 10%, even more preferably from 0.1% to 5%, most preferably from 0.2% to 3%, by weight of the laundry detergent composition.

[0111] The core material comprises a perfume. The shell comprises a polymer. More particularly, the invention discloses a composition comprising a population of core-shell encapsulates (capsules), the core comprising a perfume. The shell is a polymeric material comprising the reaction product of a cross-linking agent preferably derived from an oil phase, and a chitosan preferably derived from a water phase. The cross-linking agent comprises a mixture of two or more di- and / or poly-isocyanates, preferably derived from the oil phase, the di- and / or poly-isocyanates each containing an aromatic moiety. Surprisingly, it has been found that leakage can be controlled as a function of two isocyanates, each comprising at least one aromatic moiety, which when combined with chitosan yield a low leakage capsule in different matrices and carriers, to an extent heretofore unachieved with degradable constructs. More particularly the cross-linking agent comprises an isocyanate component, wherein the isocyanate component comprises a mixture of two or more di- and / or poly-isocyanates, derived from an oil phase, the di- and / or poly-isocyanates each comprising an aromatic moiety; and each isocyanate is independently selected from the group consisting of an alpha aromatic isocyanate and a beta aromatic isocyanate. The mixture of di- and / or poly-isocyanates comprises at least one alpha isocyanate and at least one beta isocyanate as described herein.

[0112] It is understood that the test methods disclosed in the Test Methods section of the present application should be used to determine the respective values of the parameters of Applicant’s claimed subject matter as claimed and described herein.TEST METHODSDetermination of a Polymer’s Molecular Weight and Related Parameters

[0113] The following method describing gel permeation chromatograph with multi-angle light scatter and refractive index detection (GPC-MALS / RI) is used to find molecular weight distribution measurements and related values of the polymers described herein.

[0114] Gel Permeation Chromatography (GPC) with Multi- Angle Light Scattering (MALS) and Refractive Index (RI) Detection (GPC-MALS / RI) permits the measurement of absolute molecular weight of a polymer without the need for column calibration methods or standards. The GPC system allows molecules to be separated as a function of their molecular size. MALS and RI allow information to be obtained on the number average (Mn) and weight average (Mw) molecular weight.

[0115] The Mw distribution of water-soluble polymers like chitosan is typically measured by using a Liquid Chromatography system (e.g., Agilent 1260 Infinity pump system with OpenLab Chemstation software, Agilent Technology, Santa Clara, CA, USA) and a column set (e.g., 2 Tosoh TSKgel G6000WP 7.8x300mm 13um pore size, guard column A0022 6mmx 40mm PW xl-cp, King of Prussia, PA) which is operated at 40 °C. The mobile phase is 0. IM sodium nitrate in water containing 0.02% sodium azide and 0.2% acetic acid. The mobile phase solvent is pumped at a flow rate of 1 mL / min, isocratically. A multiangle light scattering (18- Angle MALS) detector DAWN® and a differential refractive index (RI) detector (Wyatt Technology of Santa Barbara, Calif., USA) controlled by Wyatt Astra® software v8.0 are used.

[0116] A sample is typically prepared by dissolving chitosan materials in the mobile phase at ~1 mg per ml and by mixing the solution for overnight hydration at room temperature. The sample is filtered through a 0.8 pm Versapor membrane filter (PALL, Life Sciences, NY, USA) into the LC autosampler vial using a 3-ml syringe before the GPC analysis.

[0117] A dn / dc value (differential change of refractive index with concentration, 0.15) is used for the number average molecular weight (Mn), weight average molecular weight (Mw), Z- average molecular weight (Mz), molecular weight of the peak maxima (Mp), and polydispersity (Mw / Mn) determination by the Astra detector software.

[0118] An illustrative example of these points on a hypothetical graph of a polymer’s molecular weight distribution is shown in FIG. 1 , where: Mn is indicated with structure number 1; Mp is indicated with structure number 2; Mw is indicated with structure number 3; and Mz is indicated with structure number 4.Viscosity

[0119] Viscosity of liquid finished product is measured using an AR 550 rheometer / viscometer from TA instruments (New Castle, DE, USA), using parallel steel plates of 40 mm diameter and a gap size of 500 μm. The high shear viscosity at 20 s'1and low shear viscosity at 0.05 s1is obtained from a logarithmic shear rate sweep from 0.01 s1to 25 s1in 3 minutes time at 21 °C.Test Method for Determining logP

[0120] The value of the log of the Octanol / Water Partition Coefficient (logP) is computed for each material (e.g., each PRM in the perfume mixture) being tested. The logP of an individual material (e.g., a PRM) is calculated using the Consensus logP Computational Model, version 14.02 (Linux) available from Advanced Chemistry Development Inc. (ACD / Labs) (Toronto, Canada) to provide the unitless logP value. The ACD / Labs’ Consensus logP Computational Model is part of the ACD / Labs model suite.Volume-weighted particle size and size distribution

[0121] The volume- weigh ted particle size distribution is determined via single-particle optical sensing (SPOS), also called optical particle counting (OPC), using the AccuSizer 780 AD 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 pm; Sensor Model Number = Sensor Model Number = LE400-05 or equivalent; Autodilution = On; Collection time = 60 sec; Number channels = 512; Vessel fluid volume = 50ml; Max coincidence = 9200. The measurement is initiated by putting the sensor into a cold state by flushing with water until background counts are less than 100. A sample of delivery capsules in suspension is introduced, and its density of capsules adjusted with DI water as necessary via autodilution to result in capsule counts of at least 9200 per ml. During a time period of 60 seconds the suspension is analyzed. The resulting volume-weighted PSD data are plotted and recorded, and the values of the desired volume-weighted particle size (e.g., the median / 50thpercentile, 5thpercentile, and / or 90thpercentile) are determined.Procedure for Determination of % Degradation

[0122] % degradation is determined by the “OECD Guideline for Testing of Chemicals” 301B CO2 Evolution (Modified Sturm Test), adopted 17 July 1992. For ease of reference, this test method is referred to herein as test method OECD 30 IBProcedure for Determination of Free Oil

[0123] This method measures the amount of oil in the water phase and uses as an internal standard solution 1 mg / ml dibutyl phthalate (DBP) / hexane.

[0124] Weigh a little more than 250 mgs of DBP into a small beaker and transfer to a 250 ml volumetric rinsing the beaker thoroughly. Fill with hexane to 250 ml.

[0125] Sample Prep: Weigh approximately 1.5-2 grams (40 drops) of the capsule slurry into a 20 ml scintillation vial and add 10 ml’s of the ISTD solution, cap tightly. Shaking vigorously several times over 30 minutes, pipette solution into an autosampler vial and analyze by GC.

[0126] Additional details. Instrumentation: HP5890 GC connected to HP Chem Station Software; Column: 5m x 0.32mm id with 1pm DB-1 liquid phase; Temperature 50 °C; for 1 minute then heat to 320 °C; @ 15 deg / min; Injector: 275 °C; Detector: 325 °C; 2 ul injection.

[0127] Calculation: Add total peak area minus the area for the DBP for both the sample and calibration.

[0128] Delivery particles can be prepared that exhibit positive zeta potentials. Such capsules have improved deposition efficiency, such as on fabrics.

[0129] In embodiments, delivery particles according to the invention have a zeta potential of at least 1 mV at a pH of 4.5.Sample preparation for biodegradability measurements

[0130] The water soluble or water dispersible material is purified via crystallization till a purity of above 95% is achieved and dried before biodegradability measurement.

[0131] The oily medium comprising the benefit agent needs to be extracted from the delivery particle slurry in order to only analyze the polymer wall. Therefore, the delivery particle slurry is freeze dried to obtain a powder. Then, it is further washed with organic solvents via Soxhlet extraction method to extract the oily medium comprising the benefit agent till weight percentage of oily medium is below 5% based on total delivery particle polymer wall. Finally, the polymer wall is dried and analyzed.

[0132] Weight ratio of delivery particle to solvent is 1 :3. Residual oily medium is determined by thermogravimetric analysis (60 minutes isotherm at 100 °C and another 60 minutes isotherm at 250 °C). The weight loss determined needs to be below 5%.Leakage

[0133] The amount of benefit agent leakage from the benefit agent containing delivery particles is determined according to the following method: i) Obtain two 1 g samples of the raw material slurry of benefit agent containing delivery particles. ii) Add 1 g of the raw material slurry of benefit agent containing delivery particles to 99 g of the consumer product matrix in which the particles will be employed and label the mixture as Sample 1. Immediately use the second 1 g sample of raw material particle slurry in Step d below, in its neat form without contacting consumer product matrix, and label it as Sample 2. iii) Age the delivery particle-containing product matrix (Sample 1) for 1 week at 35 °C in a sealed glass jar. iv) Using filtration, recover the particles from both samples. The particles in Sample 1 (in consumer product matrix) are recovered after the aging step. The particles in Sample 2 (neat raw material slurry) are recovered at the same time that the aging step began for sample 1. v) Treat the recovered particles with a solvent to extract the benefit agent materials from the particles. vi) Analyze the solvent containing the extracted benefit agent from each sample, via chromatography.vii) Integrate the resultant benefit agent peak areas under the curve and sum these areas to determine the total quantity of benefit agent extracted from each sample. viii) Determine the percentage of benefit agent leakage by calculating the difference in the values obtained for the total quantity of benefit agent extracted from Sample 2 (S2) minus Sample 1 (SI), expressed as a percentage of the total quantity of benefit agent extracted from Sample 2 (s2), as represented in the equation below:For a sample of powder, two duplicates of this procedure are done, and the results are averaged. The standard deviation is calculated from the two points and provided with the average value.Method of olfactive evaluation

[0134] After the fabrics have been treated, expert perfumers perform an olfactive assessment for on the dry fabrics perfume intensity at the DRY touchpoints (Dry Fabric Odor = DFO), at a RUB touchpoint (Rubbed Fabric Odor = RFO; fabrics are dried for one day, smelled for DFO, then manually manipulated by rubbing the fabric against itself and smelled again for RFO), and the scores are averaged. Scores are based on a perfume odor intensity scale from 0 to 100, where 0=no perfume odor, 25=slight perfume odor, 50=moderate perfume odor, 75=strong perfume odor, and 100=extremely strong perfume odor. The “Delta RFO” can be reported, which is the difference between the RFO and the DFO.

[0135] The broadness index can be calculated by determining the particle size at which 95% of the cumulative particle volume is exceeded (95% size), the particle size at which 5% of the cumulative particle volume is exceeded (5% size), and the median particle size (50% size — 50% of the particle volume both above and below this size). Broadness Index = ((95% size) -(5% size) / 50% size).

[0136] Method to determine headspace concentration above treated dry fabrics.

[0137] The cotton tracers are analyzed by a fast headspace GC / MS (gas chromatography mass spectrometry) approach. 4X4 cm aliquots of the terry towel cotton tracers were transferred to 25 ml headspace vials. The fabric samples were equilibrated for 10 minutes®65 °C. The headspace above the fabrics was sampled via SPME (50 / 30pm DVB / Carboxen / PDMS) approach for 5 minutes. The SPME fiber was subsequently on-line thermally desorbed into the GC. The analytes were analyzed by fast GC / MS in full scan mode. Ion extraction of the specific masses of the PRMs was used to calculate the total HS response and perfume headspace composition above the tested legs.

[0138] %NCOThe % NCO of Isocyanate compounds is calculated as below Equation:Where Number of NCO groups is the count of isocyanate groups present in the compound, MW NCO group is the molecular weight of a single NCO group,MW Isocyanate compound is the molecular weight of the entire isocyanate compound, excluding any solvent or other substances that may be mixed with the isocyanate.When isocyanate is used as a mixture of multiple isocyanates, the %NC0 is reported as the weighted sum of mass percentages for each individual isocyanate within the mixture.

[0139] All temperatures herein are in degrees Celsius (°C) unless otherwise indicated.Unless otherwise specified, all measurements herein are conducted at 20 °C and under the atmospheric pressure.

[0140] All percentages and ratios are calculated by weight unless otherwise indicated. All percentages and ratios are calculated based on the total composition unless otherwise indicated.

[0141] It should be understood that every maximum numerical limitation given throughout this specification includes every lower numerical limitation, as if such lower numerical limitations were expressly written herein. Every minimum numerical limitation given throughout this specification will include every higher numerical limitation, as if such higher numerical limitations 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.

[0142] In the following examples, the abbreviations, materials or tradenames correspond to the materials listed in Table 1. The examples are intended to be illustrative in nature and are not intended to be limiting.Table 1. Materials - chitosanThe di- and / or poly- isocyanates comprise an aromatic moiety. The isocyanates employed have two functional groups: an isocyanate group and an aromatic moiety. For ease of reference, the isocyanate molecules can be subdivided into several classifications.A first grouping can be on the basis of the presence or absence of an aromatic moiety within the whole molecule; hence the following two classification are defined:1- isocyanate comprising at least one aromatic moiety.2- isocyanate not comprising any aromatic moiety.For convenience, the presence of the aromatic moiety can be further classified as either alpha or beta based on carbon-atom naming. Hence the isocyanate comprising an aromatic moiety can be subdivided.1. i) isocyanate comprising an alpha aromatic moiety; and,1. ii) isocyanate comprising a beta aromatic moiety.For ease of reference, Group 1, i) and ii) classifications are then referred to as:1. i) alpha aromatic1. ii) beta-aromatic and Group 2 as2. “non-aromatic”This naming convention is reflected in Table 2 below:Table 2. Materials - isocyanateIt is theorized that the aromatic ring can affect reactivity. Surprisingly it was found that isocyanate comprising alpha aromatic moieties are more reactive than isocyanate comprising beta aromatic moieties. This is believed due to the nature of the electron-withdrawing aromatic ring, enhancing the electrophilic character of the isocyanate group (NCO). Isocyanate comprising alpha aromatic moiety or moieties have a phenyl ring attached to the NCO group, which is theorized to enhance reactivity. The delocalization of electrons in the aromatic ring is believed to make the alpha carbon even more electron-deficient, making it a stronger electrophile, hence more prone to nucleophilic interaction with amines such with the chitosan amine group. Isocyanate comprising a beta aromatic moiety or moieties, on the other hand, have less of the influence of an electron-withdrawing aromatic ring and are attached to the beta carbon. While they are still reactive, they are generally less reactive than their alpha aromatic counterparts. This can lead to faster reaction rates, making the alpha aromatics, such as of Group 1 i), more efficient in certain applications. However, their high reactivity can also make them more challenging to handle and may require additional precautions such as the potential unwanted reactivity with PRMs. Surprising, unexpected improvements were found when theisocyanate component is selected to comprises a mixture of two or more isocyanates each comprising an aromatic moiety; and each isocyanate is independently selected from the group consisting of an alpha aromatic isocyanate and a beta aromatic isocyanate. It is to be understood that the isocyanate can be di- or polyisocyanate.EXAMPLES

[0143] The examples provided below are intended to be illustrative in nature and are not intended to be limiting.Example protocol for; Comparative Example 1, Examples 1A, IB, 1C

[0144] Comparative examples and examples were prepared following procedures below:

[0145] An acid and potassium persulfate treated chitosan solution is prepared by dispersing 134.79 g chitosan into 2875 g water while mixing in a jacketed reactor at 60°C. If needed, Potassium persulfate (“KPS”) was then added to the chitosan dispersion under mixing, at a level such that after the hydrolyzing and depolymerize step, the chitosan solution viscosity is between 50cP-2000cP. The pH of the chitosan solution was then adjusted to 5.9 using 36.8g 32% hydrochloric acid and 4.2g 90% formic acid under mixing. The temperature of the chitosan solution is then increased to 85 °C over 60 minutes and then held at 85 °C for a period of time to hydrolyze and depolymerize the chitosan. The temperature is then reduced to 25 °C after the hydrolyzing step over a period of 90 minutes to obtain the acid and potassium persulfate treated chitosan solution. The formed chitosan stock solution was used for preparation of capsule in Comparative Examples and Examples below.

[0146] A water phase is prepared by mixing 435.07 g of the chitosan stock solution in a jacketed reactor. An oil phase is prepared by mixing 127.25 g perfume and 31.82 g isopropyl myristate together along with isocyanates at room temperature according to the weight listed on Table 2 and 3. The oil phase is added to the water phase under high shear milling, preferably in under 20 minutes, to obtain an emulsion with desired particle size. The emulsion is heated to 60 °C over 45 and then heated to 85 °C in 60 minutes and maintained at this temperature for 6 hours while mixing before cools down to 25°C in 90 minutes.

[0147] Example protocol for Examples: ID, IE, IF, 1G

[0148] Comparative examples and examples were prepared following procedures below:

[0149] An acid and potassium persulfate treated chitosan solution is prepared by dispersing 146.0 g chitosan into 3100 g water while mixing in a jacketed reactor at 60°C. If needed, Potassium persulfate (“KPS”) was then added to the chitosan dispersion under mixing, at a level such that after the hydrolyzing and depolymerize step, the chitosan solution viscosity is between 50cP-2000cP. 49.82g 32% hydrochloric acid was added under mixing. The temperature of the chitosan solution is then increased to 85 °C over 60 minutes and then held at 85 °C for a period of time to hydrolyze and depolymerize the chitosan. The temperature is then reduced to 25 °C after the hydrolyzing step over a period of 90 minutes to obtain the acid and potassium persulfate treated chitosan solution. The formed chitosan stock solution was used for preparation of capsule in Comparative Examples and Examples below.

[0150] A water phase is prepared by mixing 354.0 g of the chitosan stock solution along with 82.6g RO water in a jacketed reactor. An oil phase is prepared by mixing 105 g perfume and 26.2 g isopropyl myristate together along with isocyanates at room temperature according to the weight listed on Tables 2 and 3. The oil phase is added to the water phase under high shear milling to obtain an emulsion with desired particle size. The emulsion is heated to 60 °C over 45 and then heated to 85 °C in 60 minutes and maintained at this temperature for 6 hours while mixing before cools down to 25 °C in 90 minutes.• Perfume leakage in Unit Dose ArticlePerfume leakage in a unit-dose article (detergent composition detailed in Table 5) was assessed according to the method “ Perfume Leakage” provided in the Test Methods section above. Table 3 Comparatives illustrate a single Beta-aromatic isocyanate and a single Alphaaromatic isocyanate, respectively, exhibit higher perfume leakage than the Examples.Table 1 : Samples at different level of Alpha and Beta IsocyanateThe leakage profile of delivery particles comprising differing concentrations of an alphaaromatic isocyanate in a combination with Beta- aromatic isocyanate is graphed in Figure 1. Figure 1 visually illustrates the surprising reduction in the relative leakage in SUD detergent wherein the ratio of the alpha aromatic isocyanate to the beta aromatic isocyanate is from 5 to 70% by weight, preferably from 25 to 65% by weight, most preferably from 30 to 50% by weight of the isocyanate component.Example protocol for Examples: Comparative Example 3, Comparative Example 4, Comparative Example 5, Example 1G:All samples of Table are made with the same weight concentration 66% for Isocyanate 1 and 34% for Isocyanate 2. As illustrated in Table , delivery particles using a combination of aromatic isocyanates according to the invention achieve significantly lower leakage in dosage form (“SUD”) matrices.

[0151] Comparative examples and examples were prepared following procedures below:

[0152] An acid and potassium persulfate treated chitosan solution is prepared by dispersing 42.03 g chitosan into 893 g water while mixing in a jacketed reactor at 60°C. If needed, Potassium persulfate (“KPS”) was then added to the chitosan dispersion under mixing, at a level such that after the hydrolyzing and depolymerize step, the chitosan solution viscosity is between 50cP-2000cP. 11.48g 32% hydrochloric acid and 1.28g 90% formic acid was then added under mixing. The temperature of the chitosan solution is then increased to 85 °C over 60 minutes and then held at 85 °C for a period of time to hydrolyze and depolymerize the chitosan. The temperature is then reduced to 25 °C after the hydrolyzing step over a period of 90 minutes to obtain the acid and potassium persulfate treated chitosan solution. Four batches of this process were combined to form the chitosan stock solution used for preparation of capsule in Comparative Examples 2, 3, and 4 and Examples 1H.

[0153] A water phase is prepared by mixing 440.8 g of the chitosan stock solution in a jacketed reactor. An oil phase is prepared by mixing 128.9 g perfume and 32.23 g isopropyl myristate together along with isocyanates at room temperature according to the weight listed on Table 4. The oil phase is added to the water phase under high shear milling to obtain an emulsion with desired particle size. The emulsion is heated to 60 °C over 45 and then heated to 85 °C in 60 minutes and maintained at this temperature for 6 hours while mixing before cools down to 25 °C in 90 minutes.Table 2: Samples with different types of isocyanates

[0154] Capsules according to the invention can have core to wall ratios even as high as 95% core to 1% wall by weight. In applications where enhanced degradability is desired, higher core to wall ratios can be used such as 99% core to 1% wall, or even 99.5% to 0.5% by weight or higher. With appropriate selection of core to wall ratios, the shell of the composition according to the invention can be selected to achieve a % degradation of at least 40% degradation after 28 days, and of at least 60% degradation after at least 60 days when tested according to test method OECD 301B.Headspace perfume concentration above treated fabricsFabrics were treated with a unit-dose article (detergent composition detailed in Table 5) according to the Fabric Treatment Method provided in the Test Methods section above (via the “Method to determine headspace concentration above treated fabrics'’).According to the data in Table 5, the comparative example shows no DFO and RFO Headspace benefit, while Example ID displays significant higher headspace values at DFO and RFO. It is believed that the benefit of Example ID compared to the comparative example is due to the optimal combination of Beta-aromatic isocyanate and Alpha- aromatic isocyanate which leads to a lower perfume leakage in a unit dose article as highlighted in Table 3, which subsequently leads to higher Headspace Concentration above dry and rubbed fabrics.Table 5; Headspace perfume concentration• Detergent composition in Unit Dose ArticleThe following is an exemplary water-soluble unit dose base formulation, prepared through mixing of the individual starting materials in a batch type process. The below composition can be enclosed in a water-soluble film, preferably a polyvinyl alcohol based water soluble film, more specifically a water soluble film comprising a blend of a polyvinylalcohol homopolymer and a carboxylated anionic polyvinylalcohol copolymer, alternatively a blend of polyvinylalcohol homopolymers, alternatively a water soluble film comprising a carboxylated anionic polyvinylalcohol copolymer such as M8630 or M8310 ex the MonoSol company, alternatively a combined use thereof.Table 6: Liquid detergent composition*Nuclease enzyme is as claimed in co-pending European application 19219568.3**Lutensol FP620 ex BASF - ethoxylated polyethyleneimine (PEI600 EO20)***poly ethylene glycol graft polymer comprising a polyethylene glycol backbone (PluriolE6000) and hydrophobic vinyl acetate side chains, comprising 40% by weight of the polymersystem of a polyethylene glycol backbone polymer and 60% by weight of the polymer system of the grafted vinyl acetate side chains**** Lutensit Z96 (zwitterionic poly amine ex BASF - zwitterionic hexamethylene diamine according to below formula : 100% quatemized and about 40% of the polyethoxy (EO24) groups are sulfonated).

[0155] Uses of singular "a," "an," are intended to cover both the singular and the plural, unless otherwise indicated herein or clearly contradicted by context. The terms "comprising," "having," "including," and "containing" are to be construed as open-ended terms. All references, including publications, patent applications, and patents, cited herein are hereby incorporated by reference. Any description of certain embodiments as "preferred" embodiments, and other recitation of embodiments, features, or ranges as being preferred, or suggestion that such are preferred, is not deemed to be limiting. The invention is deemed to encompass embodiments that are presently deemed to be less preferred and that may be described herein as such. All methods described herein can be performed in any suitable order unless otherwise indicated herein or otherwise clearly contradicted by context. The use of any and all examples, or exemplary language (e.g., "such as") provided herein, is intended to illuminate the invention and does not pose a limitation on the scope of the invention. Any statement herein as to the nature or benefits of the invention or of the preferred embodiments is not intended to be limiting. This invention includes all modifications and equivalents of the subject matter recited herein as permitted by applicable law. Moreover, any combination of the above-described elements in all possible variations thereof is encompassed by the invention unless otherwise indicated herein or otherwise clearly contradicted by context. The description herein of any reference or patent, even if identified as "prior," is not intended to constitute a concession that such reference or patent is available as prior art against the present invention. No unclaimed language should be deemed to limit the invention in scope. Any statements or suggestions herein that certain features constitute a component of the claimed invention are not intended to be limiting unless reflected in the appended claims.

Claims

ClaimsWhat is claimed is:

1. A composition comprising a population of delivery particles, wherein the delivery particles comprise a core and shell surrounding the core, wherein the core comprises a benefit agent, wherein the shell comprises a polymeric material that is the reaction product of chitosan derived from an aqueous phase, and a cross-linking agent, wherein the cross-linking agent comprises an isocyanate component, the isocyanate component comprising a mixture of two or more di- and / or polyisocyanates, derived from an oil phase, the di- and / or poly-isocyanates each comprising an aromatic moiety; and, wherein each isocyanate is independently selected from the group consisting of an alpha aromatic isocyanate and a beta aromatic isocyanate, and wherein the mixture of di- and / or poly-isocyanates comprises at least one alpha isocyanate and at least one beta isocyanate.

2. The composition according to claims 1 wherein the weighted %NCO of the aromatic isocyanate of the isocyanate component is from 15 to 32% or even from 20 to 26%, or even from 20 to 25% by weight, or even from 21 to 25% by weight.

3. The composition according to claim 1 wherein the mass percent of the alpha aromatic isocyanate in the isocyanate component is from 1 to 99% by weight, preferably from 5 to 90% by weight, most preferably from 30 to 60% by weight.

4. The composition according to claim 1 wherein the alpha aromatic isocyanate is selected from the group consisting of:šndwherein R is a biuret, a uretdione, a isocyanurate, a polyol, a polyol having a urethane group, a urea, a polyamine, a polyamine having a urea group, a polyacid with an anhydride group, a poly-isocyanate comprising a biuret, a poly-isocyanate comprising a uretdione, or a polyisocyanate comprising an isocyanurate.

5. The composition according to claim 1 wherein the alpha aromatic isocyanate is selected from the group consisting of:wherein n is an integer from 1 to 24,šndThe composition according to claim 1 wherein the beta aromatic isocyanate is selected from the group consisting of:wherein R is a biuret, a uretdione, a isocyanurate, a polyol, a polyol having a urethane group, a urea, a polyamine, a polyamine having a urea group, a polyacidwith an anhydride group, a poly-isocyanate comprising a biuret, a poly-isocyanate comprising a uretdione, or a polyisocyanate comprising an isocyanurate.

7. The composition according to claim 1 wherein the beta aromatic isocyanate selected from the group consisting of:

8. The composition according to claim 1 wherein the chitosan is pretreated at a pH of6.5 or less, and at a temperature of at least 25 °C., or pretreated with a redox initiator, or both.

9. The composition according to claim 1 wherein the isocyanate component comprises at least two di- and / or poly-isocyanates selected from methylenediphenyl diisocyanate, polymeric methylenediphenyl isocyanate, and a trimethylol propane-adduct of xylylene diisocyanate.

10. The composition according to claim 1, wherein the beta aromatic isocyanate is selected from the group consisting of xylylene diisocyanate, trimethylolpropane adducts of xylylene diisocyanate, tetramethylxylidene diisocyanate, isomers thereof, adducts thereof, and combinations thereof,11. The composition according to claim 1, wherein the alpha aromatic isocyanate is selected from the group consisting of toluene diisocyanate, methylene diphenyl diisocyanate, polymeric methylene diphenyl diisocyanate, naphthalene diisocyanate, phenylene diisocyanate, isomers thereof, adducts thereof, and combinations thereof.

12. The composition according to claim 1 wherein the isocyanate component comprises methylenediphenyl isocyanate, polymeric methylenediphenyl isocyanate, and a trimethylol propane- adduct of xylylene diisocyanate in a weight ratio of alpha isocyanate to beta isocyanate of from 1 :2 to 1 :1.75.

13. The composition according to claim 1 wherein the isocyanate component comprises by weight 30 to 55%, preferably 34% of a combination of methylenediphenyl isocyanate and polymeric methylenediphenyl isocyanate and from 45 to 70%, preferably 66% of a trimethylol propane-adduct of xylylene diisocyanate.

14. The composition according to claim 1, wherein the chitosan, is characterized by a weight average molecular weight of from about lOOkDa to about 80,000 kDa, or even from 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, even more preferably from about 100 kDa to about 200 kDa.

15. The composition according to claim 1 wherein the required isocyanates are each present in at least 20 mole percent of the total isocyanate component.

16. The composition according to claim 1 wherein the ratio of chitosan to the crosslinking agent, based on weight, is 79:21 to 10:90, or even 67:33 to 11:89, or even 50:50 to 13:87.

17. The composition of claim 1, wherein the shell has a biodegradability above 30% CO2 in 60 days when tested according to test method OECD 30 IB, preferably above 40% CO2, more preferably above 50% CO2, even more preferably above 60% CO2 (maximum 95%).

18. The composition according to claim 1 wherein at least 21 wt % of the shell is comprised of moieties derived from the chitosan.

19. The composition according to claim 1 wherein the core-shell encapsulate has a ratio of core to shell of at least 75:25, or at least 99: 1, or even at least 99.5:

0. 5, on the basis of weight.

20. The composition according to claim 1 wherein the benefit agent is selected from the group consisting of perfume, fragrance, agricultural active, phase change material, essential oil, lubricant, colorant, preservative, antimicrobial active, antifungal active, herbicide, antiviral active, antiseptic active, antioxidant, biological active, deodorant, emollient, humectant, exfoliant, ultraviolet absorbing agent, corrosion inhibitor, silicone oil, wax, bleach particle, fabric conditioner, malodor reducing agent, dye, optical brightener, antiperspirant active and mixture thereof.

21. The composition according to claim 1, wherein the benefit agent is a fragrance, preferably a fragrance comprising perfume raw materials characterized by a logP of from about 2.5 to about 4.5.

22. The composition according to claim 1, wherein the core comprises in addition a partitioning modifier selected from the group consisting of isopropyl myristate, vegetable oil, modified vegetable oil, mono-, di-, and tri-esters of C4-C24 fatty acids, dodecanophenone, lauryl laurate, methyl behenate, methyl laurate, methyl palmitate, methyl stearate, and mixtures thereof, preferably isopropyl myristate.

23. The composition according to claim 1 wherein the delivery particles have a median particle size of from 1 to 200 microns.

24. The composition according to claim 1 wherein the encapsulate has a zeta potential of at least 1 mV at a pH of 4.5.

25. An article of manufacture incorporating the delivery particles according to any of the preceding claims.

26. The article of manufacture according to claim 25 wherein the article is selected from the group consisting of an agricultural formulation, a slurry encapsulating an agricultural active, a population of dry encapsulates encapsulating an agricultural active, an agricultural formulation encapsulating an insecticide, and an agricultural formulation for delivering a preemergent herbicide.

27. The article of manufacture according to claim 26 wherein the agricultural active is selected from the group consisting of an agricultural herbicide, an agricultural pheromone, an agricultural pesticide, an agricultural nutrient, an insect control agent and a plant stimulant.

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