Biodegradable chitosan microcapsules

Abstract

The present disclosure relates to biodegradable core-shell microcapsules having a shell composed of a biopolymer, such as chitosan, cross-linked with an isocyanate and a tannic acid, in particular a hydrolyzed tannic acid. The present disclosure also relates to methods for preparing the biodegradable core-shell microcapsules and consumer products containing the microcapsules.

Description

Technical Field

[0001] The present disclosure relates to biodegradable core-shell microcapsules having a shell composed of a biopolymer cross-linked with an isocyanate and tannic acid, particularly hydrolyzed tannic acid. In particular, the biopolymer is chitosan. The present disclosure also relates to a method for preparing the biodegradable core-shell microcapsules and consumer products containing the microcapsules. Background Art

[0002] Current commercial fragrance capsules, including melamine-formaldehyde and polyurea, are made of synthetic materials that are not readily biodegradable. This is a problem for a number of reasons. First, consumers are demanding more environmentally friendly products. Second, due to the possibility of new regulations, such as from the European Chemicals Agency (ECHA), the use of microplastics in various consumer products (e.g., cosmetics, detergents, etc.) may be banned. Therefore, the demand for fragrance delivery technologies continues to grow, in which the capsule wall materials are more biodegradable and / or sustainable, and will meet the requirements set forth in any currently existing and newly proposed regulations banning the use of microplastics.

[0003] Core-shell microcapsules based on gelatin have been described, which are indicated as being biodegradable. See WO 2021 / 122636 A1 (Firmenich) and WO 2021 / 122633A1 (Firmenich). In addition, microcapsules composed of chitosan and tannic acid have been described. See WO 2020 / 131890 A1 (International Flavors & Fragrances Inc.), CN 113453654A (International Flavors & Fragrances Inc.), WO 2020 / 209908A1 (International Flavors & Fragrances Inc.), and WO 2020 / 209907A1 (International Flavors & Fragrances Inc.). In addition, microcapsules composed of natural polymers such as chitosan, carrageenan or gum arabic have been proposed. See WO 2021 / 018947 A1 (Firmenich), WO 2021 / 122630 A1 (Firmenich), WO 2021 / 116306 A1 (Firmenich), and WO 2020 / 194910 A1 (Fujifilm). However, the degree or rate of biodegradability of these latter capsules has not been described. Even assuming that the microcapsules disclosed herein above can pass any current biodegradation test (e.g., OECD 301F or OECD 310), they may still not be 'truly' biodegradable and not fully compliant with ECHA. This means that the microcapsules may not meet the requirements of the proposed ECHA regulations, i.e., the material forming the microcapsule wall cannot be a "blend" of a biodegradable material (e.g., a biopolymer) and a non-biodegradable material. Alternatively, if the microcapsule wall is considered a blend, all components of the blend as a whole need to meet the requirements for biodegradability (eg, minimally meet at least the OECD 301F or OECD 310 test).

[0004] Therefore, there is still a need in the industry for microcapsules composed of sustainable and / or biodegradable materials that are chemically stable and / or deliver active materials such as fragrances in consumer products. Preferably, the material used to form the microcapsules does not form a blend of biodegradable materials and non-biodegradable materials. Alternatively, if the material used to form the microcapsule wall does form a blend, the blend contains only a small amount (i.e., ≤10%, ≤5%, ≤3%, ≤1%, or ≤0.5%) of non-biodegradable materials, or all components of the blend as a whole meet the requirements of biodegradability. The microcapsules preferably also provide acceptable fragrance characteristics and performance in use. The present invention meets this demand and other needs in the industry. Summary of the invention

[0005] The present invention is based on the discovery that biodegradable and / or sustainable microcapsule shells can be prepared by crosslinking biopolymers such as chitosan with multifunctional isocyanates and tannic acid.

[0006] Thus, the present invention provides biodegradable core-shell microcapsules, wherein: (i) the shell comprises chitosan (e.g., fungal chitosan) crosslinked with a polyfunctional isocyanate having at least two isocyanate functional groups and tannic acid that hydrolyzes at a pH between 5.0 and 8.5; and (ii) the core comprises an active material; wherein the shell of the microcapsule has a biodegradability of at least 20%, 30%, 40%, 50%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95% or 98% within 60 days according to OECD 301F or OECD 310, preferably at least 60% within 60 days according to OECD 301F. In some aspects, the shell further comprises carrageenan, gum arabic (gum arabic), or a combination thereof. In other aspects, the polyfunctional isocyanate is biuret, isocyanurate, allophanate, uretdione, oligomeric hexamethylene diisocyanate or a combination thereof. Preferably, the isocyanate is dispersed in a solvent. In yet other aspects, the shell is further cross-linked with an amino acid, preferably an amino acid selected from the group consisting of: lysine, arginine, ornithine, cysteine, serine, threonine, asparagine, glutamine and a combination thereof, more preferably an amino acid is lysine.

[0007] The active material is a fragrance, a flavoring agent, an agricultural active substance, a pesticide, an insecticide, a herbicide, a fungicide, a pharmaceutical active substance, a nutritional active substance, an animal nutritional active substance, a food active substance, a microbial active substance, a malodor counteractant, and / or a cosmetic active substance, preferably a fragrance. The present invention is also based on the following discovery: a high-performance fragrance composition composed of certain ultra-high-impact fragrance ingredients and high-impact fragrance ingredients provides improved perceived intensity, perceived persistence and / or perceived fidelity of the fragrance characteristics at various "contact points" related to the laundry experience (e.g., opening a fabric conditioner container, wet clothes when opening a washing machine after washing clothes, turning on a washer dryer after drying clothes, drying clothes on a drying rack, and wearing washed clothes). Preferably, the fragrance comprises at least one, at least two, at least three, at least four, at least five, at least six, at least seven, at least eight, at least nine or at least ten high-performance fragrance ingredients selected from the group consisting of ultra-high-impact fragrance ingredients as listed in Table 1 and high-impact fragrance ingredients as listed in Table 2, and optionally at least one additional fragrance ingredient.

[0008] Also provided is a method for preparing biodegradable core-shell microcapsules and biodegradable core-shell microcapsules obtainable by the method. According to the method, an aqueous solution comprising chitosan is emulsified with an oil phase comprising an active material to form an emulsion. Subsequently, chitosan is cross-linked by adding isocyanate and tannic acid hydrolyzed under a pH between 5.0 and 8.5 to the emulsion, thereby forming a biodegradable core-shell microcapsule. Preferably, chitosan is fungal chitosan, and isocyanate is a polyfunctional isocyanate with at least two isocyanate functional groups. In some aspects, the aqueous solution further comprises carrageenan, gum arabic (gum arabic) or a combination thereof. In other aspects, the polyfunctional isocyanate is biuret, isocyanurate, allophanate, uretdione, oligomeric hexamethylene diisocyanate or a combination thereof.

[0009] In yet another aspect, the present invention provides biodegradable core-shell microcapsules, wherein: (a) the biodegradable core-shell microcapsules have a level of self-condensed polyfunctional isocyanate of less than 10%, less than 5%, less than 3%, less than 1% or less than 0.5% relative to the total weight of polyfunctional isocyanate used to form the wall of the microcapsule; or (b) the material used to form the wall of the microcapsule does not form a combination of a biodegradable material and a non-biodegradable material; or (c) the material used to form the wall of the microcapsule forms a combination of a biodegradable material and a non-biodegradable material. (d) a material for forming the wall of the microcapsule forms a combination of biodegradable and non-biodegradable materials, wherein the biodegradability of all components of the combination within 60 days is at least 20%, 30%, 40%, 50%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95% or 98% according to OECD 301F.

[0010] In yet further aspects, the shell is further cross-linked with an amino acid, preferably an amino acid selected from the group consisting of lysine, arginine, ornithine, cysteine, serine, threonine, asparagine, glutamine, and combinations thereof, preferably lysine. Preferably, the active material is a fragrance, a flavoring agent, an agricultural active substance, a pesticide, a pharmaceutical active substance, a nutritional active substance, an animal nutritional active substance, a food active substance, a microbial active substance, a deodorant, and / or a cosmetic active substance, preferably a fragrance, more preferably a fragrance comprising at least one, at least two, at least three, at least four, at least five, at least six, at least seven, at least eight, at least nine or at least ten high performance fragrance ingredients selected from the ultra high impact fragrance ingredients as listed in Table 1 and the high impact fragrance ingredients as listed in Table 2, and optionally at least one additional fragrance ingredient.

[0011] Also provided are consumer products comprising the biodegradable core-shell microcapsules of the present invention, wherein the consumer product is preferably a fabric softener, a fabric conditioner, a detergent, a fragrance enhancer, a fabric refresher spray, a shower gel, a bath soap, a shampoo, a hair conditioner, a body spray, a hair refresher spray, a hair dye, a hair moisturizer, a skin moisturizer, a hair care agent, a skin care agent, an antiperspirant, a deodorant, an insect repellent, a candle, a surface cleaner, a bathroom cleaner, a bleach, a cat litter, a freshening spray, a pesticide, an insecticide, an herbicide, a fungicide, or a paint.

[0012] In a particular aspect, the present invention also provides biodegradable core-shell microcapsules, wherein the shell comprises a biopolymer cross-linked with an isocyanate and tannic acid hydrolyzed at a pH between 5.0 and 8.5, and the core comprises an active material, wherein the microcapsule shell has a biodegradation rate of at least 60% within 60 days according to OECD 301F, and the active material comprises a fragrance, a flavor, an agricultural active substance, a pesticide, an insecticide, a herbicide, a fungicide, a pharmaceutical active substance, a nutritional active substance, an animal nutritional active substance, a food active substance, a microbial active substance, a deodorant, and / or a cosmetic active substance, preferably a fragrance, more preferably a fragrance comprising at least one, at least two, at least three, at least four, at least five, at least six, at least seven, at least eight, at least nine or at least ten high-performance fragrance ingredients selected from the group consisting of super high-impact fragrance ingredients as listed in Table 1 and high-impact fragrance ingredients as listed in Table 2, and optionally at least one additional fragrance ingredient. Ideally, the biopolymer used according to this aspect comprises: (i) chitosan, pectin, chitooligosaccharide, carrageenan, modified guar gum, modified dextran, gum arabic (gum arabic), modified gum arabic (modified gum arabic), alginate, modified starch, modified cellulose, or a combination thereof, preferably the biopolymer is fungal chitosan; or (ii) protein, gelatin, collagen, glucoamylase, hydrolyzed protein, fermented protein, hydrophobin, enzyme, partially neutralized citrate, or a combination thereof; or (iii) a combination of (i) and (ii).

[0013] Unless otherwise indicated, all parts, percentages and ratios referred to herein and in the claims are by weight. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] While the specification concludes with claims particularly pointing out and distinctly claiming the invention, it is believed that the invention will be better understood from the following description of the accompanying drawings, in which:

[0015] Figure 1LC / MS analysis of hydrolyzed tannic acid at pH 5.5, 6.5 and 8.5 is shown. The relative amounts of different molecular weight species of hydrolyzed tannic acid (HTA) are shown, with greater amounts of gallic acid being produced as pH increases.

[0016] Figure 2 The biodegradation rate of microcapsule 7 is shown.

[0017] Figure 3 The biodegradation rate of the microcapsule 10 is shown. DETAILED DESCRIPTION

[0018] The foregoing general description and the following detailed description are exemplary and explanatory only and do not limit the invention as defined by the appended claims.Other features and benefits of any one or more embodiments will be apparent from the following detailed description and from the claims.

[0019] As used herein, the terms "comprises," "comprising," "includes," "including," "has," "having," or any other variation thereof, are intended to cover a non-exclusive inclusion. For example, a process, method, article, or apparatus that includes a list of elements is not necessarily limited to only those elements, but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. In addition, unless expressly stated to the contrary, "or" refers to an inclusive or and not to an exclusive or. For example, a condition A or B is satisfied by any of the following: A is true (or exists) and B is false (or does not exist), A is false (or does not exist) and B is true (or exists), and both A and B are true (or exist).

[0020] Moreover, "a / an" is used to describe the elements and components described herein. This is done only for convenience and to give a general sense of the scope of the invention. This description should be interpreted as including one / a or at least one / a, and the singular also includes the plural, unless it is obvious that it is otherwise intended.

[0021] When amount, concentration or other values ​​or parameters are given with scope, preferred range or a series of upper preferred values ​​and / or lower preferred values, this should be understood as particularly disclosing all scopes formed by any pairing of any upper range limit or preferred value and any lower range limit or preferred value, and whether these scopes are disclosed separately.When numerical range is enumerated herein, unless otherwise indicated, the scope is intended to include all integers and fractions in its endpoints and the scope.For example, when enumerating the scope of "1 to 10", the enumerated scope should be interpreted as including "1 to 8", "3 to 10", "2 to 7", "1.5 to 6", "3.4 to 7.8", "1 to 2 and 7-10", "2 to 4 and 6 to 9", "1 to 3.6 and 7.2 to 8.9", "1-5 and 10", "2 and 8 to 10", "1.5-4 and 8" and other scopes.

[0022] Although compositions and methods are described herein as "comprising" various components or steps, these compositions and methods can also "consist essentially of" or "consist of" the various components or steps, unless otherwise stated.

[0023] In the present invention, the flavor microcapsules are prepared using biopolymers such as chitosan (preferably chitosan derived from shellfish chitosan or fungal chitosan) and other natural and biodegradable materials such as carrageenan, gum arabic, tannic acid, etc. Compared with commercially available products prepared with melamine formaldehyde and polyurea polymers that are not easily biodegradable, the microcapsules prepared according to the method described herein have excellent biodegradation characteristics, robust stability and / or excellent system performance.

[0024] The biodegradable core-shell microcapsules of the present invention have a core comprising at least one active material, and a shell comprising at least one biopolymer crosslinked with a polyfunctional isocyanate having at least two isocyanate functional groups and tannic acid, wherein the tannic acid is preferably hydrolyzed tannic acid used alone or in combination with unhydrolyzed tannic acid.

[0025] As used herein, "biodegradable" with respect to a material (such as a microcapsule shell as a whole and / or a biopolymer of a microcapsule shell) has no real or perceived health and / or environmental issues and is capable of and / or does undergo physical, chemical, thermal, microbiological and / or biological degradation. Ideally, the microcapsule shell and / or biopolymer is considered "biodegradable" when it passes one or more of the following tests, including: Respirometric biodegradation in aquatic media, available from the Organization for Economic Co-operation and Development (OECD), the International Organization for Standardization (ISO, www.iso.org), and the American Society for Testing and Materials (ASTM), including but not limited to OECD 301F or 310 (ready biodegradation), OECD 302 (intrinsic biodegradation), ISO 17556 (solid irritation study), ISO 14851 (fresh water irritation study), ISO 18830 (marine sediment irritation study), OECD 307 (soil irritation study), OECD 308 (sediment irritation study), and OECD 309 (water irritation study). Preferably, the microcapsule is readily biodegradable as determined using the respirometric biodegradation method, OECD 301F or OECD 310 test in an aquatic medium. More preferably, the shell of the microcapsule is biodegradable if it has a biodegradation rate of at least 20%, 30%, 40%, 50%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95% or 98% based on the weight of the shell within 60 days according to the respirometry biodegradation method in an aquatic medium, the OECD 301F or OECD 310 test, or most preferably has a biodegradation rate of at least 60% based on the weight of the shell within 60 days according to the OECD 301F test.

[0026] As used herein, the terms "capsule", "microcapsule" and "core-shell microcapsule" are used interchangeably and refer to a substantially spherical structure having a well-defined core and a well-defined envelope or wall. The "core" is composed of any active material or material that is microencapsulated. The "wall" is a structure formed by a microencapsulated biopolymer surrounding a core of microencapsulated active material. Typically, the wall of a microcapsule is composed of a continuous polymeric phase having an inner surface and an outer surface. The inner surface is in contact with the microcapsule core. The outer surface is in contact with the environment in which the microcapsule is located, which is, for example, an aqueous phase, skin or hair. Ideally, the wall protects the core from deterioration due to the influence of oxygen, moisture, light, and other compounds or other factors; limits the loss of volatile core materials; and releases the core materials under desired conditions. In this regard, the core-shell microcapsules of the present invention provide controlled release and / or diffusion release of active materials. As used herein, "controlled release" refers to retaining the active material in the core until a specific triggering condition occurs. Such triggers include, for example, friction, swelling, pH change, enzymes, temperature change, ionic strength change, or a combination thereof.

[0027] As used herein, the terms "shell" and "wall" are used interchangeably and refer to the shell that encapsulates the core material of the microcapsule. As used herein, the terms "polyfunctional isocyanate" and "polyisocyanate" are used interchangeably.

[0028] As used in the context of the present disclosure, "biodegradable core-shell microcapsules" or "biodegradable core-shell microcapsule compositions" refer to slurries or suspensions of biodegradable core-shell microcapsules produced according to the methods and examples described herein. The biodegradable core-shell microcapsule compositions of the present invention can be used directly in consumer products, washed, coated, dried (e.g., spray dried) and / or combined with one or more other microcapsule compositions, active materials and / or carrier materials.

[0029] For the purposes of this disclosure, a "biopolymer" is a polymer obtained from a natural source (e.g., plant, fungus, bacteria, marine or animal) or a modified biopolymer thereof. In some aspects, the biopolymer used to prepare the microcapsules is water-soluble (i.e., water-soluble before cross-linking). In other aspects, the biopolymer is a polypeptide, a polysaccharide, or a polyphenolic compound. In certain aspects, the biopolymer of the microcapsule wall is a single type of polymer, such as a polypeptide, a polysaccharide, or a polyphenolic compound. In other aspects, the biopolymer of the microcapsule wall is a combination of multiple polymers and / or multiple types of polymers, for example, (a) a combination of at least one polypeptide and at least one polysaccharide, (b) a combination of at least one polypeptide and at least one polyphenolic compound, (c) a combination of at least one polysaccharide and at least one polyphenolic compound, (d) a combination of at least one polypeptide and at least one polysaccharide and at least one polyphenolic compound, or (e) a combination of two or more polysaccharides and at least one polyphenolic compound.

[0030] As used herein, the term "sustainable" with respect to materials such as microcapsule shells and / or active materials (e.g., flavor ingredients) refers to "bio-based" materials of atoms or molecules obtained from biomass (e.g., from materials containing organic carbon from a renewable source). Such sources of carbon can be derived from agricultural products, plants, animals, fungi, microorganisms, marine or forestry materials.

[0031] In some aspects, the shell of the biodegradable core-shell microcapsule comprises at least one polysaccharide selected from the group consisting of chitosan, pectin, chitosan oligosaccharide, carrageenan, modified guar gum, modified glucan, gum arabic (gum arabic), modified gum arabic (modified gum arabic), modified starch, modified cellulose, alginate, and mixtures thereof; at least one polypeptide selected from the group consisting of protein, gelatin, collagen, hydrolyzed protein, fermented protein, hydrophobic protein, enzyme, and mixtures thereof; partially neutralized citrate or any combination of the above-mentioned biopolymers and components. In some aspects, the shell of the biodegradable core-shell microcapsule comprises at least two, three, or four polysaccharides. In particular, the shell can comprise chitosan and carrageenan and / or gum arabic (gum arabic).

[0032] In a particular aspect, the shell of the core-shell microcapsule comprises chitosan. "Chitosan" is a linear polysaccharide composed of randomly distributed β-(1-4)-linked D-glucosamine (deacetylated units) and N-acetyl-D-glucosamine (acetylated units). The important characteristics that determine the functionality of chitosan are the degree of deacetylation (% DDA) and the molecular weight (M). w). Chitosan is technically defined as chitin with more than 60% DDA. Chitosan with a higher %DDA has more positively charged amine groups when dissolved in solution. In the production of chitosan traditionally derived from crustaceans, large amounts of high temperature caustic solutions are required to chemically remove the acetyl groups. Due to the nature of the fermentation, fungal production of chitosan allows very high %DDA values, with the ability to routinely produce up to 99% DDA. In a preferred aspect, chitosan is obtained from a fungal source or derived from fungal chitin by chemical deacetylation. Exemplary fungal sources that can be used to prepare chitosan include, but are not limited to, Pleurotus ostreatus and Aspergillus niger.

[0033] In some aspects, chitosan has a degree of deacetylation (DDA) of 50% to 95%, preferably 65% ​​to 90%. In other aspects, chitosan has a DDA of ≥80%. In some aspects, chitosan has an average molecular weight of 500Da to 1,000,000Da, preferably 2,000Da to 500,000Da, more preferably 10,000Da to 400,000Da, or most preferably 50,000Da to 250,000Da.

[0034] In order to achieve the desired performance characteristics (i.e., active material retention and controlled release), the biopolymer is cross-linked with one or more cross-linking agents. As used herein, "cross-link" is a bond, atom or group connecting a chain of atoms in a biopolymer. According to the present invention, a biopolymer (e.g., chitosan, carrageenan, and / or gum arabic) is cross-linked with a polyfunctional isocyanate having at least two isocyanate functional groups and tannic acid, wherein the tannic acid is hydrolyzed tannic acid, unhydrolyzed tannic acid, or a combination thereof. Alternatively, the biopolymer can be further cross-linked with an amino acid, preferably an amino acid selected from the group consisting of: lysine, arginine, ornithine, cysteine, serine, threonine, asparagine, glutamine and a combination thereof, more preferably the amino acid is lysine.

[0035] As used herein, the term "polyisocyanate" is a collective term for compounds containing at least two isocyanate groups in the molecule (which those skilled in the art will understand to mean free isocyanate groups having the following general structure: RN=C=O). The simplest form of polyisocyanates is diisocyanates. These have the general structure O=C=NRN=C=O, wherein R typically represents an aliphatic, alicyclic and / or aromatic group. In certain aspects, polyfunctional isocyanates are oligomeric polyisocyanates obtained from hexamethylene diisocyanate (HDI), which is a monomeric diisocyanate. In certain aspects, polyfunctional isocyanates are oligomeric polyisocyanates having, in particular, a biuret, isocyanurate, allophanate, uretdione and / or oligomeric HDI structure.

[0036] It has been found that comprising tannic acid, especially hydrolyzed tannic acid improves the biodegradability of microcapsules.Therefore, in some aspects, biopolymer, preferably chitosan is cross-linked with tannic acid, wherein the tannic acid is hydrolyzed tannic acid, unhydrolyzed tannic acid or its combination.Hydrolyzed tannic acid can be prepared as described herein by subjecting tannic acid to a pH between 5.0 and 8.5, preferably between 5.5 and 7.0, most preferably between 5.5 and 6.5 for a suitable amount of time to produce tannic acid significantly hydrolyzed to a variety of low molecular weight substances.Ideally, tannic acid is hydrolyzed so that gallic acid constitutes a considerable percentage of the hydrolyzate.

[0037] The core of the biodegradable core-shell microcapsule of the present invention comprises at least one active material. In some aspects, the microcapsule comprises two, three, four or more active materials in the core. The active materials that can be encapsulated in the core-shell microcapsule of the present invention include but are not limited to spices, flavoring agents, agricultural active substances, pesticides, insecticides, herbicides, fungicides, pharmaceutical active substances, nutritional active substances, animal nutritional active substances, food active substances, microbial active substances, deodorants, and / or cosmetic active substances, preferably spices, more preferably comprising at least one, at least two, at least three, at least four, at least five, at least six, at least seven, at least eight, at least nine or at least ten spices selected from the group of high-performance spices of the super high-impact spices listed in Table 1 and the high-impact spices listed in Table 2.

[0038] Table 1 - High Impact Fragrance Ingredients 1 Available from International Flavors & Fragrances.

[0039] Table 2 - High Impact Fragrance Ingredients 1 Available from International Flavors & Fragrances, New York. 2 Available from TRIPPER PTE Ltd. (Indonesia). 3 Available from TREATT & CO. Ltd. (UK).

[0040] In addition to the fragrance ingredients listed in Table 1 and Table 2, the fragrance may further include at least one additional fragrance ingredient. Preferably, the fragrance may further include 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 15, 20, 25, 30, 35, 40 or more additional fragrance ingredients not listed in Table 1 and Table 2. Non-limiting examples of such additional fragrance ingredients include those described in US2018 / 0325786 A1, US 4,534,891, US 5,112,688 and US 5,145,842. Other suitable active materials that may be encapsulated include active materials listed on pages 38-50 of WO 2016 / 049456.

[0041] The additional perfume ingredients make up the total perfume composition when combined with one or more perfume ingredients of Table 1 and Table 2. In this aspect, the balance of 100 wt % relative to the total weight of the perfume component consists of one or more super high impact perfume ingredients of Table 1 and high impact perfume ingredients of Table 2 and one or more additional perfume ingredients.

[0042] It has been unexpectedly found that perfumes containing certain types of ultra-high impact and high impact perfume ingredients produce high-performance perfume ingredients for fabric care compositions, preferably fabric conditioners, thereby improving the performance of the fragrance characteristics and / or system. As used herein, the term "fragrance characteristics" means the description of the perceived fragrance by the nose of a person at any time. The fragrance characteristics may change over time. The fragrance characteristics are the result of a combination of the base notes, middle notes and top notes (if any) of the fragrance. The characteristics of the base notes are to provide animal, woody, sweet, amber or musky characteristics, and are not prone to volatility. The middle notes are related to the desired characteristics (such as floral characteristics (e.g., jasmine, rose), fruity, marine, aromatic or spicy characteristics). "Top notes (top note / head note)" provide citrus, green, light or fresh characteristics and tend to evaporate quickly due to their high volatility. The fragrance characteristics consist of two characteristics: "intensity" and "characteristics". "Intensity" refers to the perceived intensity, while "characteristics" refers to the odor impression or quality of the fragrance, i.e., fresh, clean, etc.

[0043] In some embodiments, the active material is an agricultural active substance, a pesticidal agent, an insecticide, a herbicide, and / or a fungicide. Encapsulating agricultural active substances, pesticidal agents, insecticides, herbicides, and / or fungicides can increase their efficacy, extend their shelf life and protect the environment. In some embodiments, the insecticide is an organophosphate insecticide. In some embodiments, the insecticide can be an organophosphate insecticide selected from the group consisting of: acephate, methyl azinphos-methyl, chlorpyrifos, chloroxyfos, methyl chlorpyrifos, diazinon, dimethoate, ethoxychlor, cypermethrin, fenthion, fenamiphos, thiamethoxam, malathion, methamidophos, methidathion, oxydemeton, sulfone, parathion, methyl parathion, phorate, phosmet, propylbromophos, trichlorfon, and mixtures thereof. In some embodiments, the insecticide is selected from the group consisting of: cypermethrin, bifenthrin, lambda-cyhalothrin, and mixtures thereof. In some embodiments, the herbicide is selected from the group consisting of clomazone, acetochlor, pendimethalin, and mixtures thereof. In some embodiments, the fungicide is tebuconazole.

[0044] In addition to the active material, the present invention also contemplates incorporating additional components, including solvents and core regulator materials, in the core encapsulated by the microcapsule wall. Other components include solubility regulators, density regulators, stabilizers, viscosity regulators, pH regulators, deposition aids, capsule formation aids, catalysts, processing aids, or any combination thereof. These components may be present in the wall or core of the capsule, or outside of the capsule in the microcapsule composition to improve solubility, stability, deposition, capsule formation, etc. In addition, these additional components may be added after and / or during the preparation of the microcapsule composition of the present invention. Suitable solvents or dispersants include, for example, isopropyl alcohol, ethyl acetate, acetic acid, caprylic acid triglyceride, polyoxyethylated castor oil, anionic, nonionic and cationic block polymers, etc., or any combination thereof.

[0045] Suitable solvents for dispersing isocyanates include ethyl acetate, 3-methoxybutyl acetate, diethylene glycol monoethyl ether acetate (DGMEA), propylene glycol diacetate, diethyl malonate, glycerol triacetate, triethyl citrate, ethyl acetoacetate, benzyl acetone, butyl carbitol acetate, and the like, or any combination thereof.

[0046] In some aspects, the shell of the core-shell microcapsule comprises between 0.2% and 11.0%, preferably between 1.2% and 4.5% of the biopolymer based on the weight of the shell; and between 0.1% and 10%, preferably between 0.5% and 5% of the crosslinking agent based on the weight of the shell. In some aspects, the core of the core-shell microcapsule comprises between 0.5% and 1.0%, preferably between 0.1% and 0.5% of the dispersant based on the weight of the core; between 10.0% and 90.0%, preferably between 15.0% and 40.0% of the active material based on the weight of the core; between 5.0% and 90.0%, preferably between 10.0% and 50.0% of the modifier based on the weight of the core; and optionally between 0.01% and 0.5%, preferably between 0.05% and 0.2% of the rheology modifier based on the weight of the core.

[0047] In certain aspects, the shell of the core-shell microcapsule comprises at least one, two, or three biopolymers. In certain aspects, the shell comprises between 0% and 5.0%, preferably between 0.2% and 2.0%, carrageenan based on the dry weight of the microcapsule; between 0.1% and 3.5%, preferably between 0.5% and 3.0%, gum arabic (gum arabic) based on the dry weight of the microcapsule; and / or between 0.1% and 3.0%, preferably between 0.5% and 1.5%, chitosan based on the dry weight of the microcapsule.

[0048] In certain aspects, one crosslinking agent or a combination of two, three, or four crosslinking agents is used. In particular, the crosslinking component of the microcapsule comprises between 0.01% and 2.0%, preferably between 0.05% and 0.5%, of polyisocyanate based on the weight of the microcapsule; between 0.0% and 10%, preferably between 0.1% and 5.0%, of tannic acid based on the weight of the microcapsule; between 0.1% and 10%, preferably between 0.2% and 5.0%, of hydrolyzed tannic acid based on the weight of the microcapsule; and / or between 0.0% and 1.8%, preferably between 0.0% and 1.0%, of L-lysine based on the weight of the microcapsule.

[0049] The active material component (e.g., perfume) of the core-shell microcapsule is preferably present at between 5.0% and 90.0% by weight, preferably between 10.0% and 40.0% by weight of the microcapsule. When the perfume comprises a combination of the super high impact perfume ingredients listed in Table 1 and the high impact perfume ingredients listed in Table 2, the perfume can be used in an aqueous fabric conditioner product at a significantly reduced dosage (e.g., at least 2, 5 to 10 times lower level) compared to a standard perfume that does not comprise the super high impact perfume ingredients listed in Table 1 and the high impact perfume ingredients listed in Table 2.

[0050] In particular, the perfume of the present invention can be used at a dosage level of ≤1 wt% relative to the total weight of the microcapsule composition without significant effect on the fragrance characteristics (i.e., perceived fragrance intensity, perceived fragrance persistence and / or perceived fragrance fidelity), especially for selected properties (e.g., freshness and / or cleanliness). In some aspects, the perfume is used at a dosage level of less than or equal to 1 wt%, 0.99 wt%, 0.95 wt%, 0.9 wt%, 0.8 wt%, 0.7 wt%, 0.6 wt%, 0.5 wt%, 0.4 wt%, 0.3 wt%, 0.2 wt%, 0.1 wt%, 0.05 wt% or 0.01 wt%, or any range defined by any pair of the foregoing values, based on the total weight of the aqueous fabric conditioner composition.

[0051] Additional components of the core-shell microcapsules include between 0.1% and 1.0%, preferably between 0.1% and 0.3%, based on the weight of the microcapsule, of a dispersant such as polyoxyethylated castor oil; between 5.0% and 90.0%, preferably between 10% and 50.0%, based on the weight of the microcapsule, of a core conditioning agent such as caprylic and capric triglyceride; and optionally between 0.05% and 1.0%, preferably between 0.1% and 0.5%, based on the weight of the microcapsule, of a rheology conditioning agent such as xanthan gum.

[0052] The microcapsules of the present invention each have a size (diameter) in the range of 0.1 μm to 1000 μm (e.g., 0.5 μm to 500 μm, 1 μm to 200 μm, 1 μm to 100 μm, and 1 μm to 50 μm), with the lower limit being 0.1 μm, 0.5 μm, 1 μm, 2 μm, 5 μm, or 20 μm, and the upper limit being 1000 μm, 500 μm, 200 μm, 100 μm, 75 μm, 50 μm, 30 μm, 20 μm, 10 μm, or 5 μm.

[0053] Another aspect of the present invention is to turn to the use of flavor ingredients and / or microcapsules derived from the concept of "green chemistry". Green chemistry focuses on the design of products and processes that minimize environmental impact, especially by using renewable feedstocks. In other words, the raw materials or feedstocks used to make flavor ingredients and / or microcapsules should be sustainable and not depleted, where technically and economically feasible. Preferably, the flavor components and / or microcapsules of the present invention have a biorenewable carbon (BRC) content of at least 50%, at least 55%, at least 60%, at least 65%, at least 70%, at least 75%, at least 80%, at least 85%, at least 90% or at least 95%. As used herein, "BRC" refers to carbon and non-fossil-based carbon that is part of the earth's natural environment. BRC is a naturally occurring renewable, reused and / or upgraded carbon resource that can be supplemented by natural reproduction or other recycling processes in a limited time (such as in a person's lifetime) to replace the part that is exhausted by use and consumption. BRC will not include carbon from virgin crude oil.

[0054] In some aspects, one or more non-restricted or non-encapsulated active materials may also be included in the microcapsule composition after curing. Such active materials may be the same or different from the encapsulated active materials and may be included at a level of 0.01% to 20% by weight, or more preferably 2% to 10% by weight of the microcapsule composition (i.e., microcapsule slurry).

[0055] The microcapsules of the present invention can also be combined with one or more other delivery systems, such as polymer-assisted delivery compositions (US 8,187,580), fiber-assisted delivery compositions (US2010 / 0305021), cyclodextrin host-guest complexes (US 6,287,603 and US2002 / 0019369), pro-perfumes (WO 2000 / 072816 and EP 0 922 084), and any combination thereof. More exemplary delivery systems that can be incorporated are coacervate capsules, cyclodextrin delivery systems, and pro-perfumes.

[0056] In addition, microcapsules with one or more different features can be combined to provide desired or customized release profiles and / or stability.Especially, the microcapsule composition can comprise the combination of two or more types of microcapsules, the difference of these microcapsules being the weight ratio between their encapsulation wall material, microcapsule size, wall material amount, wall thickness, degree of polymerization, degree of crosslinking, wall material and active material, core regulator, scavenger, active material, curing temperature, heating rate during curing, curing time, rupture force or fracture strength or its combination.In some respects, the microcapsule composition comprises two, three, four, five, six, seven or more different types of capsules, the difference of these capsules being one or more in the above-mentioned feature mentioned.

[0057] When evaluating storage stability, the retention of fragrances in the microcapsules can be measured directly after storage in the consumer product base at a desired temperature and time period (such as four weeks, six weeks, two months, three months or longer). The preferred way is to measure the total headspace of the consumer product at a specified time and compare the result with the headspace of the control consumer product, which indicates a 0% retention rate by directly adding the total amount of fragrances present in the control consumer product. Alternatively, the consumer product can be tested for performance after the storage period and compared with the performance of the fresh product by analysis or sensory evaluation. This measurement usually involves measuring the fragrance headspace above the substrate used with the product, or the odor evaluation of the same substrate. In some aspects, the retention of active materials in the core of the microcapsule is evaluated in the consumer product base, for example, under storage conditions for a long period of time such as in the range of 25°C to 40°C, or more preferably in the range of 30°C to 37°C, or most preferably at a temperature of 37°C for at least 2 weeks, 4 weeks, 6 weeks, 8 weeks, 16 weeks or 32 weeks. In some aspects, when added to the consumer product base, the microcapsules of the present invention retain at least 30% of the active material. In particular aspects, when added to a consumer product base, the microcapsules of the present invention retain between 40% and 90% of the active material after storage at 37°C for at least 4 weeks, 8 weeks, or 12 weeks.

[0058] Typically, the biodegradable core-shell microcapsules of the present invention are prepared by: (i) an aqueous solution comprising chitosan is emulsified with (ii) an oil phase comprising an active material to form an emulsion; and (b) chitosan is cross-linked by adding isocyanate and tannic acid, preferably tannic acid hydrolyzed at a pH between 5.0 and 8.5 to the emulsion to form a biodegradable core-shell microcapsule. In some aspects, the chitosan is fungal chitosan, the isocyanate is a polyfunctional isocyanate (e.g., biuret, isocyanurate, allophanate, uretdione, oligomeric hexamethylene diisocyanate, or a combination thereof) with at least two isocyanate functional groups, and the tannic acid is a hydrolyzed tannic acid, an unhydrolyzed tannic acid, or a combination thereof. In other aspects, the aqueous solution optionally further comprises carrageenan, gum arabic (gum arabic), or a combination thereof and / or the shell is further optionally cross-linked with an amino acid. Preferably, the amino acid is selected from the group consisting of: lysine, arginine, ornithine, cysteine, serine, threonine, asparagine, glutamine, and combinations thereof. Preferably, the amino acid is lysine. In addition, the preparation method may further include the step of curing the microcapsules. As used herein, "curing" refers to the process of toughening or hardening the polymer by cross-linking the polymer chains through heat, chemical additives or light radiation. In some aspects, the microcapsules are cured at an elevated temperature, for example, between 35°C and 150°C, preferably between 55°C and 90°C, for between 1 hour and 5 hours.

[0059] The preparation method may alternatively or further include a step of drying the microcapsules to remove water. The drying temperature is in the range of 20°C to 250°C, or at room temperature. In some aspects, the microcapsules are dried by a dehumidifier configured to supply dry air to the microcapsules, a radiant heat source for promoting the drying of the microcapsules, or placing the microcapsules under airflow to obtain dry, free-flowing microcapsules. It should be understood that any standard method known to those skilled in the art for such drying is also applicable.

[0060] Compared to conventional polyisocyanate and biodegradable polymer microcapsules, the wall of the microcapsules of the present invention is formed by chitosan crosslinked with a polyfunctional isocyanate having at least two isocyanate functional groups and tannic acid, wherein the polyfunctional isocyanate is added in a manner whereby self-condensation of the polyisocyanate is substantially or completely eliminated during the microcapsule preparation process. Preferably, the biodegradable core-shell microcapsules of the present invention are substantially or completely free of self-condensing polyisocyanates and thus exhibit superior (or "true") biodegradability properties (i.e., by reducing or avoiding blends of biodegradable and non-biodegradable materials). In particular, the biodegradable core-shell microcapsules have a level of self-condensing polyfunctional isocyanates (i.e., polyureas and / or polyurethanes) of less than 10%, less than 5%, less than 3%, less than 1% or less than 0.5% relative to the total weight of the polyfunctional isocyanate used to form the wall of the microcapsule.

[0061] The biodegradable core-shell microcapsule composition of the present invention is very suitable for inclusion in any of a variety of consumer products that require controlled release of active materials (e.g., spices or flavors). The microcapsule composition of the present invention can be added directly to a consumer product base, or printed onto a product base or a movable product conveyor (e.g., a non-stick belt) for drying. See WO 2019 / 212896Al. The biodegradable core-shell microcapsules can be added to a consumer product base at a level in the range of 0.001% to 50% by weight, or more preferably 0.01% to 50% by weight of the consumer product base. In particular, the biodegradable core-shell microcapsules are suitable for inclusion in consumer products such as fabric softeners, fabric conditioners, detergents, fragrance enhancers, fabric refresher sprays, body washes, bath soaps, shampoos, hair conditioners, body sprays, hair refresher sprays, hair dyes, hair moisturizers, skin moisturizers, hair care products, antiperspirants, deodorants, skin care products, insect repellents, candles, surface cleaners, bathroom cleaners, bleaches, cat litter, freshener sprays, pesticides, insecticides, herbicides, fungicides, or paints.

[0062] The values ​​and dimensions disclosed herein should not be understood as being strictly limited to the exact numerical values ​​recited. Instead, unless otherwise specified, each such value is intended to mean the recited value and a functionally equivalent range around that value. For example, a value disclosed as "50%" is intended to mean "about 50%". Examples

[0063] The following non-limiting examples are provided to further illustrate the present invention but should not be construed as limitations of the present invention as many variations of the invention are possible without departing from the spirit or scope of the invention. Example 1: Materials and Methods

[0064] Sample preparation for biodegradability assessment. To ensure a clear and accurate biodegradability assessment, the microcapsules were subjected to a rigorous cleaning process to purify the microcapsule shell prior to the biodegradability assessment. The purpose of the cleaning process is to remove material that is not part of the microcapsule shell and / or is not tightly bound to the microcapsule shell.

[0065] To clean the microcapsules, 300 grams (g) of the microcapsule slurry was washed with water at least three times and then centrifuged at 6000 rpm for 15 minutes (Sorvall LYNX 6000 ultracentrifuge). After centrifugation, the flavor capsules formed a cake layer and settled on the top layer. The water layer and the sediment layer were separated by a peristaltic pump at 300 rpm ( The water wash was repeated twice more and the wet capsule cake was collected and freeze-dried (Millrock Technology, Laboratory Series Dryer, Model LD53) to remove water. The dried spice microcapsules were subjected to multiple methanol extractions at 65°C (50 g of dry capsules in 300 mL of methanol, Universal Extractor E-800) until the residual fragrance in the purified wall was less than 2% (w / w). The cleaned capsule wall was vacuum dried at 30°C until completely dry and then used for biodegradability evaluation as set forth in OECD301F / OECD310.

[0066] Preparation of hydrolyzed tannic acid (HTA). A 30% tannic acid solution was adjusted to pH 5.5, 6.0, 6.5, 7.5 and 8.5 with an aqueous solution of NaOH (5 to 25 wt / wt.%). The treated solution was stirred at 300 rpm for 18 hours at room temperature. Optionally, the hydrolysis reaction was quenched by adjusting the pH to 4.0 using a 30% citric acid solution. LC / MS analysis demonstrated that tannic acid was significantly hydrolyzed into a variety of low molecular weight substances, among which a larger amount of gallic acid ( Figure 1 ). Exemplary microcapsules 9 to 13 were prepared using tannic acid hydrolyzed at pH 5.5 / 6.0.

[0067] General process for preparing microcapsules. Biodegradable microcapsules are produced by: dissolving the wall-forming biomaterial in water to prepare an aqueous phase; preparing an oil phase containing the core material and the core modifier; forming an emulsion by mixing the aqueous phase and the oil phase under shear; adding a solution containing an isocyanate dissolved in an organic solvent to the emulsion to form a slurry; adding a hydrolyzed tannic acid and lysine solution to the slurry, and curing the microcapsules at a temperature of 35°C to 150°C. All percentages are by weight unless otherwise indicated. Example 2: Chitosan / tannic acid microcapsules (microcapsules 1)

[0068] First, the oil phase was mixed with 102 g of Eden (a fragrance commercially available from International Flavors & Fragrances, New York (NY)) and 11.34 g of caprylic / capric triglyceride (a core solvent commercially available under the trade name Oil M-5 is commercially available; Stepan, Chicago, IL. In a separate beaker, fungal chitosan (9.0 g), gum arabic (6.0 g), and polyoxyethylated castor oil (1.8 g, a capsule forming aid, available under the trade name 8240 is commercially available; Stepan Company, Chicago, IL) was dissolved in water to obtain 457.11 g of an aqueous solution. The oil phase was then emulsified into the water phase using an IKA T25 shearing device at a shear rate of 8600 rpm for three minutes to form an oil-in-water emulsion.

[0069] An oil-in-water emulsion was prepared at room temperature with constant mixing. An aliphatic polyisocyanate (1.2 g) (polyisocyanate based on hexamethylene diisocyanate (HDI), sold under the trade name N100A is commercially available; Bayer, Leverkusen, Germany) in ethyl acetate (4.5 g) (Sigma-Aldrich, St. Louis, MO) was added to the emulsion. The mixture was cured at room temperature for 30 minutes. Then, the mixture was cured at 60°C for 1 hour. Subsequently, 10.8 g of a 30% aqueous solution of tannic acid (Tanal-02; Ajinomoto, Japan) was added with constant mixing. The slurry was cured at 60°C for 2 hours. L-Lysine (4.131 g of a 15% solution; Sigma-Aldrich, St. Louis, MO) was added, and the slurry was cured for another hour to obtain microcapsules 1 dispersed in the aqueous phase. Example 3: Chitosan / carrageenan microcapsules (microcapsules 2)

[0070] First, the oil phase was prepared by mixing 102 g of a model fragrance and 11.34 g of caprylic / capric triglyceride (core solvent, sold under the trade name oil M-5 commercially available; Stepan Company, Chicago, IL). In a separate beaker, fungal chitosan (9.0 g), gum arabic (encapsulation aid, 6.0 g), carrageenan A-CAT (IFF, Nutrition and Biosciences, Wilmington, DE) (6.0 g), and polyoxyethylated castor oil (1.8 g, as 8240 is commercially available; Stepan Company, Chicago, IL) was dissolved in water to obtain 457.11 g of an aqueous solution. The oil phase was then emulsified into the water phase at a shear rate of 8600 rpm for three minutes to form an oil-in-water emulsion.

[0071] An oil-in-water emulsion was prepared at room temperature with constant mixing. Aliphatic polyisocyanate (1.2 g) (HDI-based polyisocyanate, as N100A is commercially available; Bayer, Leverkusen, Germany) in ethyl acetate (4.5 g) (Sigma-Aldrich, St. Louis, MO) was added to the emulsion. The mixture was cured for 30 minutes at room temperature. Subsequently, 6.0 g of a 30% aqueous tannic acid solution (Tanal-02; Ajinomoto Co., Japan) was added for 30 minutes with constant mixing. Lysine (9.3 g of a 15% solution; Sigma-Aldrich, St. Louis, MO) was added, and the mixture was incubated for 30 minutes. The mixture was then heated to 60°C. Two 6.0 g portions of a 30% aqueous tannic acid solution (same as above) and two 9.3 g portions of a 15% L-lysine (same as above) were added alternately to the mixture; for each successive addition, a 30 minute cure was allowed. A total of 18.0 grams of tannic acid and 27.9 grams of lysine solution were added over a 2 hour period. The obtained slurry containing microcapsules 2 is dispersed in an aqueous phase. Example 4: Chitosan / carrageenan microcapsules (microcapsules 3)

[0072] Microcapsules 3 were prepared following the procedure described in Example 3, except that after the 2 hour cure time at 60°C, an additional one hour cure at 80°C was added. Example 5: Chitosan / carrageenan microcapsules (microcapsules 4-6)

[0073] Microcapsules 4-6 were prepared by the same method described in Example 3 using the formulations provided in Table 3.

[0074] Table 3 Example 6: Chitosan / carrageenan / HTA microcapsules (microcapsules 7-9)

[0075] Microcapsules 7-9 were prepared according to the procedure described in Example 3, except that 9.0 g or 18.0 g of HTA (hydrolyzed tannic acid) solution was used instead of untreated tannic acid solution. The formulations used for microcapsules 7-9 are provided in Table 4.

[0076] Table 4 Example 7: Chitosan / HTA microcapsules (microcapsules 10-13)

[0077] In the absence of carrageenan, microcapsules containing chitosan and hydrolyzed tannic acid (HTA) were prepared using the same method as in Example 3, except that a total of 39 grams of HTA solution was added in three equal portions. The compositions of microcapsules 10 to 13 are provided in Table 5.

[0078] Table 5 Example 8: Microcapsules from water-in-oil-in-water (W / O / W)

[0079] All solutions were prepared off-line and heated to 50°C before processing. Water-in-oil emulsions were prepared by adding the aqueous phase to the oil phase and shearing at 10,000 rpm for 1 minute using an Ultraturax mixer. Carrageenan / oil emulsions (emulsion A) were prepared by mixing 500 g of a 3% wt. solution of K carrageenan (aqueous phase A) with 250 g of Eden / MO / PGPR (80 / 17 / 2.5%) (oil phase) at 50°C and shearing at 10,000 rpm for 1 minute, wherein Eden is a fragrance oil, and MO is a mineral oil (primol), and PGPR is polyglycerol polyricinoleate (PG Polyricinoleate). Tannic acid / oil emulsion (emulsion B) was prepared by mixing 83.3 g of 20% tannic acid (aqueous phase B) with 167 g of Eden / MO / PGPR (80 / 17.5 / 2.5% wt.) (oil phase) at 50° C. and shearing at 10,000 rpm for 1 minute. The final W / O emulsion (emulsion C) was prepared by mixing emulsion A and emulsion B and gently stirring.

[0080] Microcapsules were prepared by adding 1 kg of 3 wt% chitosan solution (W2) to emulsion C and allowing the chitosan solution to sink to the bottom. 3.2 g of N100A (Bayer, Leverkusen, Germany) solution (75% 100N / 25% cymene). The mixture was gently stirred. Subsequently, the W / O / W was sheared at 7000 rpm for 1 minute using an Ultraturax. The WOW system was transferred to an overhead mixer, stirred at 500 rpm, and heated to 80°C. The temperature was maintained at 80°C for 1.5 hours. The heat was then removed and the slurry was stirred at 500 rpm for 5 hours. Example 9: Microcapsule performance

[0081] To evaluate fragrance profile performance, the microcapsule slurry was blended into a model fabric conditioner base (19% active level) as shown in Table 6.

[0082] Table 6

[0083] The fragrance loading was 0.2% net oil equivalent (NOE). The fragrance intensity of the fragrance encapsulated by the microcapsule was evaluated by performing laundry experiments using a European washing machine (Miele) using a recognized experimental protocol. Towel fabrics were used for the washing experiments and washed with European fabric conditioners containing capsules loaded with fragrance. The washed samples were removed from the washing machine and hung to dry overnight. The samples were evaluated by a panel of 12 trained judges at three different stages and rated with scores ranging from 0 to 30.

[0084] "Pre-rub" means that the towel was evaluated by the panelists before it was folded. "Gentle handling" means that the towel was evaluated after it was folded twice by the panelists. "After rubbing" means that the cloth was rubbed at least once with both hands to rupture the capsules with mechanical force, and then the signs of fragrance release were evaluated. A value of 0 indicates that the fabric produced no signs of fragrance release, 5 indicates that the fabric produced only weak intensity, and 30 indicates a very strong fragrance released from the microcapsules. The results presented in Tables 7 and 8 represent the results obtained with microcapsules encapsulating two different fragrances, Eden fragrance and Mermaid fragrance, respectively.

[0085] Table 7

[0086] Table 8

[0087] These results indicate that biodegradable microcapsules prepared according to the methods and biopolymers herein have superior performance compared to neat fragrance. Example 10: Biodegradation of chitosan microcapsules

[0088] Microcapsules 7 and 10 were washed and evaluated according to the protocol described in OECD 301F. These capsules were found to achieve >60% biodegradation within 60 days. The results for microcapsules 7 and 10 are presented in the graphs at Figure 2 and Figure 3 As a comparison, the biodegradation of MF capsules was also evaluated. The results showed that, using the same test protocol, MF capsules had only a biodegradation rate of less than 10% (data not shown). By analyzing the wall of the capsules, it was also observed that microcapsules 7 and 10 prevented the blending of biodegradable and non-biodegradable materials. Example 11: Encapsulated High Performance Fragrance Composition

[0089] High performance fragrance examples 1 and 2 are provided in Table 9 and represent fragrance formulations containing encapsulated high performance fragrance ingredients according to the present invention. Comparative fragrance example 1 is provided in Table 9 and represents an encapsulated standard fragrance that is not intended to form a high performance fragrance of the present invention. The following fragrance formulations were made by mixing the listed ingredients in the proportions listed in Table 9 at room temperature. The capsules used were microcapsules 7 and 10.

[0090] Table 9 Example 12: Fragrance Performance Using Encapsulated High Performance Fragrance

[0091] The purpose of this example is to illustrate the perfume performance benefits of using an encapsulated high performance perfume in a fabric conditioner product. A fabric conditioner composition comprising the perfume composition in Table 9 was washed with laundry and evaluated by 12 trained panelists as described in Example 9. The results from the sensory panelists were then averaged.

[0092] When compared to the benchmark encapsulated perfume composition (i.e., comparative perfume example 1), the addition of the encapsulated perfume composition comprising the high performance perfume ingredient of the present invention to the fabric conditioner base (i.e., high performance perfume examples 1 and 2) improves the fragrance intensity before drying and in the gentle drying stage. Therefore, when using the encapsulated high performance perfume according to the present invention, the fragrance intensity perception before drying and in the gentle drying stage can be further improved. Example 13: Exemplary Product Compositions

[0093] Composition A is an example of a premium fragrance composition according to the present invention. The composition was prepared by blending the components described in Table 10 in the proportions shown.

[0094] Table 10 Element <![CDATA[Composition A (wt%) 1 ) <!-- 23 -->]]> Ethanol SD-40 60-80 <![CDATA[Microcapsule 2 > 2.5-25 DI water Moderate total 100 1 The wt % is relative to the total weight of the composition. 2 The encapsulation level depends on the fragrance loading relative to 0.3% NOE.

[0095] Composition B is an example of a fabric conditioner composition according to the present invention. This composition is prepared by admixing the components described in Table 11 in the proportions shown.

[0096] Table 11 Element <![CDATA[Composition B (wt%) 1 )]]> Platform 12 Fabric Conditioner Base 90 <![CDATA[Microcapsule 2 > 0.5–3.0 DI water Moderate total 100 1 The wt % is relative to the total weight of the composition. 2 The encapsulation level depends on the fragrance loading relative to 0.2% NOE.

[0097] Composition C is an example of a liquid detergent composition according to the present invention. This composition is prepared by admixing the components described in Table 12 in the proportions shown.

[0098] Table 12 Element <![CDATA[Composition C (wt%) 1 )]]> Black bull liquid laundry detergent 90 <![CDATA[Microcapsule 2 > 0.5-3.0 DI water Moderate total 100 1 The wt % is relative to the total weight of the composition. 2 The encapsulation level depends on the fragrance loading relative to 0.2% NOE.

[0099] Composition D is an example of a powdered detergent composition according to the present invention. This composition is prepared by admixing the components described in Table 13 in the proportions shown.

[0100] Table 13 1 The wt % is relative to the total weight of the composition. 2 The encapsulation level depends on the fragrance loading relative to 0.2% NOE.

[0101] The scope of the present invention is not intended to be limited to the specific embodiments disclosed, which are provided for example to illustrate various aspects of the present invention. Based on the description and teachings herein, various modifications to the described compositions and methods will become apparent. Such changes can be implemented without departing from the true scope and spirit of the present disclosure, and such changes are intended to fall within the scope of the present disclosure. Although the present invention can be described in conjunction with specific preferred embodiments, it should be understood that the claimed invention should not be unduly limited to such specific embodiments. In fact, various modifications to the described modes that are apparent to those skilled in the art for implementing the present invention are intended to fall within the scope of the following claims.

Claims

1. A biodegradable core-shell microcapsule, wherein: (i) the shell comprises chitosan cross-linked with a polyfunctional isocyanate having at least two isocyanate functional groups and tannic acid that hydrolyzes at a pH between 5.0 and 8.5; and (ii) the core comprises an active material; wherein the microcapsule shell has a biodegradability of at least 20%, 30%, 40%, 50%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95% or 98% based on the weight of the microcapsule shell within 60 days according to OECD 301F.

2. The biodegradable core-shell microcapsule according to claim 1, wherein: (a) the shell further comprises carrageenan, gum arabic (gum arabic), or a combination thereof; and / or (b) The polyfunctional isocyanate is biuret, isocyanurate, allophanate, uretdione, oligomeric hexamethylene diisocyanate, or a combination thereof.

3. The biodegradable core-shell microcapsule according to claim 1 or 2, wherein: (a) the biodegradable core-shell microcapsules have a level of self-condensed polyfunctional isocyanate of less than 10%, less than 5%, less than 3%, less than 1% or less than 0.5% relative to the total weight of polyfunctional isocyanate used to form the wall of the microcapsules; or (b) the material used to form the wall of the microcapsule does not form a combination of a biodegradable material and a non-biodegradable material; or (c) the material used to form the wall of the microcapsule forms a combination of biodegradable material and non-biodegradable material, wherein the level of non-biodegradable material is less than 10%, less than 5%, less than 3%, less than 1% or less than 0.5% by weight of the microcapsule wall; or (d) the material used to form the wall of the microcapsule forms a combination of a biodegradable material and a non-biodegradable material, wherein the biodegradability of all components of the combination is at least 20%, 30%, 40%, 50%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95% or 98% within 60 days according to OECD 301F.

4. The biodegradable core-shell microcapsule according to any one of the preceding claims, wherein The shell is further cross-linked with an amino acid, preferably the amino acid is selected from the group consisting of lysine, arginine, ornithine, cysteine, serine, threonine, asparagine, glutamine, and combinations thereof, more preferably the amino acid is lysine.

5. The biodegradable core-shell microcapsule according to any one of the preceding claims, wherein The chitosan is derived from shellfish chitosan or fungal chitosan, preferably fungal chitosan, and preferably the microcapsules have a biorenewable carbon (BRC) content of at least 50%, at least 55%, at least 60%, at least 65%, at least 70%, at least 75%, at least 80%, at least 85%, at least 90% or at least 95%.

6. The biodegradable core-shell microcapsule according to any one of the preceding claims, wherein The active materials include fragrances, flavors, agricultural active substances, pesticides, insecticides, herbicides, fungicides, pharmaceutical active substances, nutritional active substances, animal nutritional active substances, food active substances, microbial active substances, deodorants, and / or cosmetic active substances, preferably fragrances, more preferably fragrances comprising at least one, at least two, at least three, at least four, at least five, at least six, at least seven, at least eight, at least nine or at least ten high-performance fragrance ingredients selected from the group consisting of super high-impact fragrance ingredients as listed in Table 1 and high-impact fragrance ingredients as listed in Table 2, and optionally at least one additional fragrance ingredient.

7. A biodegradable core-shell microcapsule, wherein the shell comprises a biopolymer crosslinked with an isocyanate and tannic acid hydrolyzed at a pH between 5.0 and 8.5, and the core comprises an active material, wherein the microcapsule shell has a biodegradation rate of at least 60% based on the weight of the microcapsule shell within 60 days according to OECD 301F, and the active material comprises a fragrance, a flavor, an agricultural active substance, a pesticide, an insecticide, a herbicide, a fungicide, a pharmaceutical active substance, a nutritional active substance, an animal nutritional active substance, a food active substance, a microbial active substance, a deodorant, and / or a cosmetic active substance, preferably a fragrance, more preferably a fragrance comprising at least one, at least two, at least three, at least four, at least five, at least six, at least seven, at least eight, at least nine or at least ten high performance fragrance ingredients selected from the group consisting of the super high impact fragrance ingredients listed in Table 1 and the high impact fragrance ingredients listed in Table 2, and optionally at least one additional fragrance ingredient.

8. The biodegradable core-shell microcapsule according to claim 7, wherein The biopolymers include: (i) chitosan, pectin, chito-oligosaccharide, carrageenan, modified guar gum, modified dextran, gum arabic (gum arabic), modified gum arabic (modified gum arabic), alginate, modified starch, modified cellulose, or a combination thereof, preferably the biopolymer is fungal chitosan; or (ii) protein, gelatin, collagen, glucoamylase, hydrolyzed protein, fermented protein, hydrophobin, enzyme, partially neutralized citrate ester, or a combination thereof; or (iii) A combination of (i) and (ii).

9. A method for preparing biodegradable core-shell microcapsules, the method comprising: (a) emulsifying (i) an aqueous solution comprising chitosan with (ii) an oil phase comprising an active material to form an emulsion; as well as (b) cross-linking the chitosan by adding isocyanate and tannic acid hydrolyzed at a pH between 5.0 and 8.5 to the emulsion to form the biodegradable core-shell microcapsules; Preferably, the chitosan is fungal chitosan and the isocyanate is a polyfunctional isocyanate having at least two isocyanate functional groups.

10. The method of claim 9, wherein: The aqueous solution further comprises carrageenan, gum arabic (gum arabic), or a combination thereof.

11. The method according to claim 9 or 10, wherein: The multifunctional isocyanate is a biuret, an isocyanurate, an allophanate, a uretdione, an oligomeric hexamethylene diisocyanate, or a combination thereof, and the isocyanate is preferably dispersed in a solvent, more preferably ethyl acetate, 3-methoxybutyl acetate, diethylene glycol monoethyl ether acetate (DGMEA), propylene glycol diacetate, diethyl malonate, glycerol triacetate, triethyl citrate, ethyl acetoacetate, benzyl acetone, butyl carbitol acetate, or any combination thereof.

12. The method according to any one of claims 9 to 11, wherein: The shell is further cross-linked with amino acids, preferably selected from the group consisting of lysine, arginine, ornithine, cysteine, serine, threonine, asparagine, glutamine, and combinations thereof, preferably lysine.

13. The method according to any one of claims 9 to 12, wherein: The active materials include fragrances, flavors, agricultural active substances, pesticides, insecticides, herbicides, fungicides, pharmaceutical active substances, nutritional active substances, animal nutritional active substances, food active substances, microbial active substances, deodorants, and / or cosmetic active substances, preferably fragrances, more preferably fragrances comprising at least one, at least two, at least three, at least four, at least five, at least six, at least seven, at least eight, at least nine or at least ten high-performance fragrance ingredients selected from the group consisting of super high-impact fragrance ingredients as listed in Table 1 and high-impact fragrance ingredients as listed in Table 2, and optionally at least one additional fragrance ingredient.

14. A consumer product comprising the biodegradable core-shell microcapsules according to any one of claims 1 to 8, preferably the consumer product is a fabric softener, a fabric conditioner, a detergent, a fragrance enhancer, a fabric refresher spray, a shower gel, a bath soap, a shampoo, a hair conditioner, a body spray, a hair refresher spray, a hair dye, a hair moisturizer, a skin moisturizer, a hair care agent, a skin care agent, an antiperspirant, a deodorant, an insect repellent, a candle, a surface cleaner, a bathroom cleaner, a bleach, a cat litter, a freshening spray, a pesticide, an insecticide, a herbicide, a fungicide, or a paint.

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