阅读说明：本技术 包含防火剂的粉末状组合物 (Powdery composition comprising a fireproofing agent ) 是由 M·奥斯伯恩 B·曼德汉 于 2019-03-01 设计创作，主要内容包括：本发明涉及递送体系领域。更具体而言涉及一种粉末状组合物,其包含具有分散在聚合物基质中的疏水性活性成分的微粒,其中该粉末状组合物包含防火剂。本发明中定义的防火剂包括滑石,当该滑石存在于粉末状组合物中时,其在所述组合物的制造、处理或配制成消费品时防止粉尘爆炸的危险。(The present invention relates to the field of delivery systems. More particularly, it relates to a powdered composition comprising microparticles having a hydrophobic active ingredient dispersed in a polymer matrix, wherein the powdered composition comprises a fire retardant. Fire retardants as defined in the present invention include talc, which when present in a powdered composition, prevents the risk of dust explosion when the composition is manufactured, handled or formulated into a consumer product.)

1. A powdered composition comprising at least one dry particulate, wherein the particulate comprises a perfume or flavour oil dispersed in a polymer matrix, characterised in that the powdered composition comprises a fire retardant comprising talc.

2. A powdered composition according to claim 1, comprising:

(i) at least one dry microparticle, wherein the microparticle is made of a flavor oil or a flavor oil dispersed in a polymer matrix, and

(ii) a fire retardant comprising talc and, optionally, a flame retardant,

wherein the weight ratio between the microparticles and the talc in the powdered composition is from 10:90 to 90: 10.

3. The powdered composition according to claim 2, wherein the weight ratio between the microparticles and the talc is between 30:70 and 60:40, preferably between 40:60 and 55: 45.

4. A powdered composition according to claim 1 comprising at least one microparticle having:

-a polymer matrix,

-an oil phase comprising a flavor or flavor oil dispersed in the matrix,

wherein a fire retardant comprising talc is dispersed within the polymer matrix.

5. Powdered composition according to any of the preceding claims, wherein the powdered composition has a Minimum Ignition Energy (MIE) of ≥ 300 mJ.

6. A powdered composition according to any of the preceding claims wherein all of the flavor oil or flavor oil is not encapsulated in core-shell microcapsules in a matrix.

7. A powdered composition according to any one of claims 1 to 5 wherein all of the flavour oil or flavour oil is encapsulated in core-shell microcapsules in a matrix.

8. The powdered composition according to any one of claims 1 to 5 wherein at least a portion of the flavor oil or flavor oil is not encapsulated in core-shell microcapsules and at least a portion of the oil phase is encapsulated in core-shell microcapsules in a matrix.

9. A powdered composition according to any of the preceding claims, wherein it further comprises an anti-caking agent, preferably silicon dioxide.

10. Powder according to any of the preceding claims, characterized in that the polymer matrix is made of a water-soluble polymer comprising maltodextrin, modified starch or a mixture thereof.

11. A process for preparing a powdered composition according to any one of claims 1 to 3, 5 to 10, the process comprising the steps of: a fire retardant comprising talc is dry blended with microparticles comprising a flavor oil or a flavor oil dispersed in a polymer matrix to form a powdered composition.

12. A method according to claim 11 wherein the microparticles are obtained by spray drying an aqueous emulsion of a perfume or flavour oil in a water soluble polymer to form dried microparticles.

13. A process for preparing a powdered composition according to any one of claims 1, 4 to 10, the process comprising the steps of: a fireproofing agent comprising talc is added to an aqueous emulsion of a flavor or flavor oil in a water-soluble polymer and the resulting emulsion is spray-dried to form a powdered composition.

14. Use of talc in a powdered composition comprising microparticles made of a polymer matrix and a perfume or flavour oil dispersed in said matrix for reducing the violence of the composition to explode during its operation.

15. A powdered consumer product, preferably in the form of a dry hair cleaner, talc, a powder detergent, detergent beads, a solid fragrance, cat litter, a powder hair dye, an antiperspirant composition, a deodorant composition, comprising a powdered composition as defined in any one of claims 1 to 10.

Technical Field

The present invention relates to the field of delivery systems. More particularly, to a powdered composition comprising microparticles having a flavor oil or a flavor oil dispersed in a polymer matrix, wherein the powdered composition comprises a fire retardant. Fire retardants as defined in the present invention include talc, which prevents the risk of dust explosion during manufacture, handling or formulation of the composition.

Background

Microcapsules are widely used in the flavor (daily chemical) and seasoning (savory) industries. They constitute a delivery system for perfuming or flavoring ingredients and can be advantageously used in many applications. Encapsulation of an active such as a perfuming or flavoring ingredient simultaneously provides protection for the ingredient encapsulated therein from "attacks" such as oxidation or moisture, and on the other hand, the kinetics of flavor or fragrance release can be controlled to some extent to induce a sensory effect through sequential release.

Now, in these fields, the numerous advantageous characteristics of microcapsules are contrary to other characteristics that must be considered during their preparation, transport, storage and handling, in particular when those microcapsules are in the form of powders (known as microgranules). In fact, such delivery systems constitute combustible dusts, due to their nature, in particular due to the fact that they encapsulate volatile and combustible substances, which can form a combustible mixture when dispersed in air or another oxygen-containing gas. Unfortunately, these particles have a tendency to explode.

This problem becomes important not only during the manufacture of microparticles, but also during the microparticle handling in a factory environment for the manufacture of consumer products to which such microparticles are added.

One of the parameters for knowing the dangerous characteristics of a product is a constant K_-StIt represents the maximum explosive behavior of combustible dust in a closed system.

At constant K_-StAnd dust hazard class there is a recognized correspondence: from St-1 (low explosiveness) to St-3 (high explosiveness).

It has to be noted that the classification of dust as one of St-1 to St-3 is only a statement of explosion violence (science). It showed no ignition sensitivity of the dust nor was there any indication of the possibility of dust explosion upon formation of particulates (most often by spray drying).

Therefore, another parameter, "minimum ignition energy" (MIE) must also be considered when hazard analysis is performed on the powdered material to assess the risk of explosion.

The MIE of the dust is defined as the lowest amount of electrical energy stored in the capacitor that, when discharged across the spark gap, is insufficient to ignite the most readily ignitable dust or air mixture at atmospheric pressure, ambient temperature, and the lowest possible turbulence in a series of ten consecutive tests. MIE indicates the possibility of igniting a dust cloud through the discharge of static electricity or other such ignition sources. MIE is in joules (J).

A composition with a very low MIE value means that very low energy is sufficient to initiate an explosion.

Test protocols are described in American Institute of Chemical Engineers ASTM-E2019, VDI-2263, Center for Chemical Process Safety CCPS Publication G-95, Guidelins Handling of Powders and Bulk Solids2005, and operatinginstructions for MIKE-3 devices by c.cesana and r.siwek (manufactured by K ü hner AG, Birsfelden, CH).

It is known from the prior art that certain compounds, known as fire retardants, can minimize the risk of explosion of the powdered composition.

WO03/043728a1 discloses perfuming or flavoring particles with a fire retardant dispersed or absorbed in a polymeric carrier material. However, the fire retardant disclosed in this document must be used in a large amount as compared with the amount of the fine particles.

Furthermore, depending on the storage conditions, the microparticles may be subjected to high humidity conditions and must be stable for long periods of time.

Accordingly, there is a need to provide a cost-effective and stable powdered composition that can be manufactured and/or handled under safe conditions.

The pulverulent composition according to the invention solves this problem because it comprises talc as a flameproofing agent, which prevents the risk of explosion of the microparticles (made of an oil phase dispersed in a water-soluble polymer matrix) during their preparation and/or their handling.

Disclosure of Invention

Surprisingly, it has been found that the presence of a novel fire retardant comprising talc in a powdered composition can reduce the violence of a possible explosion. Notably, the talc may be mixed directly with the microparticles in an effective amount to reduce potential explosions during handling and formulation in a factory environment. Thus, the MIE value of the powdery composition comprising the novel flameproofing agent can be effectively increased without using a large amount of talc, compared to the amount of fine particles.

Very surprisingly, this new explosion suppressant also reduces the hygroscopicity of the powder comprising the microparticles of the invention, since little or no anti-caking agent needs to be added during the preparation of the powdered composition to obtain a composition that is stable under high humidity conditions.

Accordingly, the present invention provides a powdered composition that is cost effective, stable under high temperature and high humidity conditions and can be safely manufactured and/or handled.

A first subject of the invention is therefore a pulverulent composition comprising at least one dry particulate, wherein the particulate comprises a perfume or flavour oil dispersed in a polymer matrix, characterized in that the pulverulent composition comprises a fireproofing agent comprising talc.

A second object of the present invention is a process for preparing a powdered composition as defined above, comprising the steps of: a fire retardant comprising talc is dry blended with microparticles comprising a flavor oil or a flavor oil dispersed in a polymer matrix to form a powdered composition.

A third object of the present invention is a process for preparing a powdered composition as defined above, comprising the steps of: a fireproofing agent comprising talc is added to an aqueous emulsion of a flavor or flavor oil in a water-soluble polymer and the resulting emulsion is spray-dried to form a powdered composition.

Another object of the invention is the use of talc in a powdered composition comprising microparticles made of a polymer matrix and a perfume or flavor oil dispersed in said matrix, for reducing the violence of the composition to explode during its operation.

A final object of the invention is a powdered consumer product, preferably in the form of a dry hair cleaner, talc, a powder detergent, detergent beads, a solid fragrance, cat litter, a powder hair dye, an antiperspirant composition, a deodorant composition, comprising a powdered composition as defined above.

Detailed Description

Unless otherwise indicated, percentages (%) refer to weight percentages of the composition.

"microparticle" (microparticle) as defined herein refers to a delivery system comprising a hydrophobic active ingredient dispersed in a polymeric matrix. According to the present invention, the hydrophobic active ingredient comprises a perfume or flavor oil that may be encapsulated in core-shell microcapsules and/or freely dispersed in a matrix (i.e. not encapsulated in core-shell microcapsules).

"microcapsule" or "core-shell microcapsule" (which is used indiscriminately in the present invention) refers to a delivery system comprising an oil-based core of a hydrophobic active ingredient encapsulated by a polymeric shell.

It will be appreciated that, according to a particular embodiment, the microparticles may comprise microcapsules when at least a portion of the oil phase dispersed in the matrix is encapsulated in the microcapsules.

According to the present invention, "unencapsulated oil" refers to oil that is simply entrapped (or freely dispersed) within the polymer matrix but is not encapsulated in the microcapsules.

In contrast, according to the present invention, "encapsulated oil" refers to oil encapsulated in microcapsules.

The unencapsulated oil comprises a first hydrophobic active ingredient, while the encapsulated oil comprises a second hydrophobic active ingredient which may be the same as or may be different from the first hydrophobic active ingredient.

According to the invention, the wording "average diameter" or "average size" is used indiscriminately.

The average size d (v,0.5) was measured by a laser diffraction particle size analyzer.

The present inventors have now found a method for reducing the explosive violence of powdered compositions, possibly due to suspension in the air during their preparation or during their handling, thanks to the use of fire-protection agents comprising talc. This is a very advantageous use considering that such delivery systems are mainly composed of highly volatile components, thus constituting combustible dusts.

Furthermore, the pulverulent compositions according to the invention have proven to be less sensitive to ignition, i.e. exhibit a reduced tendency to explode. This characteristic may be measured and expressed by a minimum ignition energy or MIE parameter.

Powdered composition

A first subject of the invention is therefore a pulverulent composition comprising at least one dry particulate, wherein the particulate comprises a perfume or flavour oil dispersed in a polymer matrix, characterized in that the pulverulent composition comprises a fireproofing agent comprising talc.

According to one embodiment, the powdered composition has a Minimum Ignition Energy (MIE) value of 300mJ or greater than 300 mJ. It is believed that the powdered composition with an MIE ≧ 300mJ will not be ignited by the discharge.

One of the essential features of the invention is that the pulverulent composition comprises talc as flameproofing agent.

In addition to the dried microparticles, a fire retardant may be added to form a powdered composition (thereby forming a blend of microparticles and talc) and/or it may be present in the microparticles within the polymer matrix. The latter has safety benefits for the preparation of the microparticles themselves, while the former has safety benefits for the handling and formulation of the microparticles into consumer products.

According to one embodiment, the powdered composition comprises:

(i) at least one dry microparticle, wherein the microparticle is made of a flavor oil or a flavor oil dispersed in a polymer matrix, and

(ii) a fire retardant comprising talc;

wherein the weight ratio between the microparticles and the talc in the powdered composition is from 10:90 to 90:10, preferably from 30:70 to 60:40, more preferably from 40:60 to 55: 45.

According to another embodiment, the powdered composition comprises at least one microparticle made of:

-a polymer matrix,

-an oil phase comprising a flavor or flavor oil dispersed in the matrix.

Wherein a fire retardant comprising talc is dispersed within the polymer matrix.

The microparticles as defined in the present invention are based on the presence of an oil phase comprising at least a perfume or flavour oil dispersed in a water-soluble polymer matrix.

By "dispersed in a water-soluble polymer matrix" is meant that the oil phase is dispersed in the matrix in a non-encapsulated form (free dispersion) and/or in an encapsulated form (encapsulated in microcapsules).

The average particle size of the particles as defined in the present invention is preferably greater than 15 microns, more preferably from 35 to 300 microns.

According to one embodiment, at least a portion of the oil phase is freely dispersed in the matrix (i.e., not encapsulated in microcapsules).

According to a particular embodiment, the entire oil phase is not encapsulated in the core-shell microcapsules (i.e. is freely dispersed in the matrix).

According to another embodiment, at least a portion of the oil phase is encapsulated in microcapsules. According to a particular embodiment, at least a portion of the oil phase is encapsulated in microcapsules, while at least a portion is not encapsulated in core-shell microcapsules (i.e., is freely dispersed in the matrix).

According to another particular embodiment, the entire oil phase is encapsulated in microcapsules.

Hydrophobic active ingredients

By "hydrophobic active" is meant any active that forms a two-phase dispersion when mixed with water, either as a single ingredient, or as a mixture of ingredients.

In a preferred form of the invention, the hydrophobic active ingredient is defined as having a logP greater than 1, more preferably greater than 2.

Preferably, the hydrophobic active ingredient comprises at least 90% by weight of the compound having a logP of at least 1, more preferably it comprises at least 90% by weight of the ingredient having a logP of at least 2, relative to the total weight of the hydrophobic active ingredient. Even more preferably, the hydrophobic active ingredient comprises at least 99 wt.% of the ingredient having a logP of at least 1, most preferably it comprises at least 99 wt.% of the ingredient having a logP of at least 2, relative to the total weight of the hydrophobic active ingredient. logP is defined as the calculated logP obtained by calculation using the U.S. environmental protection agency EPI suite v3.10, 2000.

According to the invention, the hydrophobic active ingredient comprises a perfume or flavour oil. For the purposes of the present invention, the term "flavour or fragrance" encompasses flavour or fragrance ingredients or compositions of natural or synthetic origin currently used in the flavour and/or fragrance industry. Including single compounds and mixtures. Specific examples of such flavor or fragrance ingredients can be found in the current literature, e.g., Fenaroli's Handbook of flavor ingredients,1975, CRCPres; synthetic Food adjacents, 1947, by jacobs, edited by Van Nostrand; or S.arctander's Perfuel and flavour Chemicals,1969, Montclair, New Jersey (USA). Many other examples of current flavouring and/or perfuming ingredients can be found in the available patents and general literature. The flavouring or perfuming ingredients can be present in admixture with solvents, adjuvants, additives and/or other components, which are generally those currently used in the flavour and fragrance industry.

"flavouring ingredients" are well known to those skilled in the art of aromatisation because they are capable of imparting a flavour or taste to a consumable or of modifying the taste and/or flavour of said consumable, or still have its texture or mouthfeel.

By "perfuming ingredient" is understood, in the present context, a compound which is used as active ingredient in a perfuming formulation or composition, in order to impart a hedonic effect when applied to a surface. In other words, to be considered as perfuming compounds, these compounds must be recognized by a person skilled in the art of perfumery as being able to impart or modify in an active or pleasant way the odor of a composition or of an article or of a surface, and not just as having an odor. Moreover, this definition is also meant to include compounds that do not necessarily have an odor but are capable of modulating the odor of a perfuming composition, perfumed article or surface and thus modifying the perception by the user of the odor of such composition, article or surface. It also contains malodor counteracting ingredients and compositions. The term "malodor counteracting ingredient" as used herein refers to a compound that is capable of reducing the perception of malodor (i.e., unpleasant or objectionable odor to the nose of a human) by counteracting and/or masking the malodor. In a particular embodiment, these compounds have the ability to react with key compounds that cause known malodors. This reaction results in a reduction in the airborne level of malodorous substances, thereby reducing the perception of malodour. Thus, in one embodiment, the hydrophobic active comprises at least 5% by weight, preferably at least 10%, preferably at least 20%, more preferably at least 30%, most preferably at least 40% of a compound having a vapour pressure of at least 0.007Pa at 25 ℃, preferably at least 0.1Pa at 25 ℃, more preferably at least 1Pa at 25 ℃, most preferably at least 10Pa at 25 ℃, all percentages being by weight relative to the total weight of the hydrophobic active. Compounds meeting these criteria are generally considered volatile and therefore have an odor or flavor. Thus, the process of the present invention allows for the efficient encapsulation of large amounts of volatile ingredients. In a preferred embodiment of the invention, the hydrophobic active ingredient does not comprise any compound that remains odourless due to a volatility below any of the above-mentioned thresholds.

For the purposes of the present invention, the vapor pressure is determined by calculation. Thus, the method disclosed in the U.S. environmental Protection Agency (u.s.environmental Protection Agency)2000 "EPI suite" is used to determine the vapor pressure value of a particular compound or component of a hydrophobic active ingredient.

The amount of hydrophobic active ingredient in the powdered composition is preferably from 10 to 90% by weight, more preferably from 15 to 60% by weight, relative to the total weight of the composition.

According to a particular embodiment, at least a portion of the oil phase is encapsulated in the core-shell microcapsules, preferably in an amount of from 3 to 70%, preferably from 5 to 50%, based on the total weight of the microparticles.

Core-shell microcapsules (if present)

The core-shell microcapsules defined in the present invention comprise a polymeric shell and an oil-based core comprising a flavor or fragrance oil.

The nature of the polymeric shell of the microcapsules of the present invention may vary. As a non-limiting example, the shell may be made of a material selected from the group consisting of: polyureas, polyurethanes, polyamides, polyacrylates, polysiloxanes, polycarbonates, polysulfonamides, urea-formaldehyde, melamine-formaldehyde resins or aromatic polyols crosslinked with polyisocyanates, melamine-urea-formaldehyde resins, melamine-glyoxal resins, gelatin/gum arabic shell walls and mixtures thereof.

According to one embodiment, the shell of the microcapsule is based on a melamine formaldehyde resin or a melamine formaldehyde resin crosslinked with at least one polyisocyanate or aromatic polyol.

According to another embodiment, the shell of the microcapsules is polyurea-based.

The shell may also be composite, i.e. organic-inorganic, such as a composite shell consisting of at least two crosslinked inorganic particles, or a shell resulting from hydrolysis and condensation reactions of a polyalkoxysilane macromonomer composition.

According to one embodiment, the shell comprises an aminoplast copolymer, such as melamine-formaldehyde or urea-formaldehyde or cross-linked melamine formaldehyde or melamine glyoxal.

According to a particular embodiment, the core-shell microcapsules are crosslinked melamine formaldehyde microcapsules obtainable by a process comprising the steps of:

1) mixing a perfume oil with at least one polyisocyanate having at least two isocyanate functional groups to form an oil phase;

2) dispersing or dissolving an aminoplast resin and optionally a stabilizer in water to form an aqueous phase;

3) adding the oil phase into the water phase to form an oil-in-water dispersion by mixing the oil phase and the water phase, wherein the average droplet size is 1-100 microns;

4) performing a curing step to form the wall of the microcapsule; and

5) optionally drying the final dispersion to obtain dried core-shell microcapsules;

this method is described in more detail in WO2013/092375 and WO2015/110568, the contents of which are incorporated herein by reference.

According to another embodiment, the shell is a polyurea-based shell made from, for example, but not limited to, isocyanate-based monomers and an amine-containing crosslinking agent such as guanidine carbonate and/or guanazole. Preferred polyurea-based microcapsules comprise: a polyurea wall that is the polymerization reaction product between at least one polyisocyanate comprising at least two isocyanate functional groups and at least one reactant selected from the group consisting of amines (e.g., water-soluble guanidinium salts and guanidinium); a colloidal stabilizer or emulsifier; and encapsulated perfume. However, the use of amines may be omitted.

According to another embodiment, the shell is polyurethane-based, made from, for example, but not limited to, polyisocyanates and polyols, polyamides, polyesters, and the like.

According to a particular embodiment, the colloidal stabilizer comprises from 0.1% to 0.4% of polyvinyl alcohol, from 0.6% to 1% of an aqueous solution of a cationic copolymer of vinylpyrrolidone and quaternized vinylimidazole (all percentages being defined by weight relative to the total weight of the colloidal stabilizer). According to another embodiment, the emulsifier is an anionic or amphiphilic biopolymer, preferably selected from the group consisting of polyacrylates (and copolymers with acrylamide in particular), gum arabic, soy protein, gelatin, sodium caseinate and mixtures thereof.

According to a particular embodiment, the polyisocyanate is an aromatic polyisocyanate, preferably comprising phenyl, toluyl, xylyl, naphthyl or diphenyl moieties. Preferred aromatic polyisocyanates are biurets and polyisocyanurates, more preferably the polyisocyanurate of toluene diisocyanate (available from Bayer under the trade nameRC), trimethylolpropane adduct of toluene diisocyanate (available from Bayer under the trade name of r)3575 available from Mitsui Chemicals), trimethylolpropane adduct of xylylene diisocyanate (available under the trade name Mitsui Chemicals)D-110N available). According to a particular embodiment, the polyisocyanate is a trimethylolpropane adduct of xylylene diisocyanate (available under the trade name Mitsui Chemicals)D-110N available).

The preparation of aqueous dispersions/slurries of core-shell microcapsules is well known to those skilled in the art in one aspect, the microcapsule wall materials may comprise any suitable resin and include, inter alia, melamine, glyoxal, polyurea, polyurethane, polyamide, polyester, and the like, suitable resins include reaction products of aldehydes with amines, suitable aldehydes include formaldehyde and glyoxal, suitable amines include melamine, urea, benzoguanamine, glycoluril, and mixtures thereof suitable melamines include methylolmelamine, methylated methylolmelamine, iminomelamine, and mixtures thereof suitable ureas include dimethylol urea, methylated dimethylol urea, urea-resorcinol, and mixtures thereof suitable materials of manufacture are available from one or more of Solutia inc. (St L ouis, Missouri u.s.a.), Cytec Industries (westerson, New Jersey u.s.a.), Sigma-rich (St. L is, missrsai.s.a.).

According to a particular embodiment, the core-shell microcapsules are formaldehyde-free capsules. A typical process for preparing aminoplast formaldehyde-free microcapsule slurries comprises the steps of:

1) preparing an oligomeric composition comprising the reaction product of, or obtained by reacting together:

a) in the form of melamine or melamine with at least one catalyst comprising two NH groups₂C of functional group₁-C₄A polyamine component in the form of a mixture of compounds;

b) glyoxal, C_4-6Aldehyde component in the form of a mixture of a 2, 2-dialkoxyacetal and optionally a glyoxylate, glyoxal/C of said mixture_4-6The molar ratio of the 2, 2-dialkoxyethanol is from 1/1 to 10/1; and

c) a protic acid catalyst;

2) preparing an oil-in-water dispersion, wherein the droplet size is 1 to 600 μm, and comprising:

i. an oil;

aqueous medium

At least one oligomeric composition as obtained in step 1;

at least one cross-linking agent selected from the group consisting of:

A)C₄-C₁₂aromatic or aliphatic di-or triisocyanates and their biuret, triurea, trimer, trimethylolpropane adducts and mixtures thereof; and/or

B) Di-or tri-oxirane compounds of the formula

A- (Oxiran-2-ylmethyl)_n

Wherein n represents 2 or 3 and l represents C optionally containing 2 to 6 nitrogen and/or oxygen atoms₂-C₆A group;

v. optionally, containing two NH groups₂C of functional group₁-C₄A compound;

3) heating the dispersion;

4) cooling the dispersion.

This method is described in more detail in WO2013/068255, the content of which is incorporated herein by reference.

According to another embodiment, the shell of the microcapsules is polyurea-based or polyurethane-based. Examples of processes for preparing polyurea-based and polyurethane-based microcapsule slurries are described, for example, in WO2007/004166, EP2300146, EP2579976, the contents of which are also incorporated herein by reference. The process generally used for preparing polyurea-based or polyurethane-based microcapsule slurries comprises the following steps:

a) dissolving at least one polyisocyanate having at least two isocyanate groups in an oil to form an oil phase;

b) preparing an aqueous solution of an emulsifier or colloidal stabilizer to form an aqueous phase;

c) adding the oil phase to the water phase to form an oil-in-water dispersion, wherein the average droplet size is 1-500 μm, preferably 5-50 μm;

d) conditions sufficient to initiate interfacial polymerization are applied and microcapsules in the form of a slurry are formed.

According to the present invention, it is understood that, after encapsulation, the inner core of the capsule is made only of a core oil consisting of perfume oil, regardless of the nature of the microcapsule.

The microparticles defined in the present invention may contain microcapsules which may be varied by the core perfume oil inside them and/or by the walls (different chemistry, or the same chemistry but different process parameters, such as cross-linking temperature or duration).

According to a particular embodiment of the invention, the microcapsules have an outer coating selected from the group consisting of nonionic polysaccharides, cationic polymers and mixtures thereof.

Such a coating will help to drive the capsules to deposit and remain on the substrate during the washing process so that a large part of the capsules that are not destroyed at the washing stage/foaming will be transferred to the substrate (skin, hair fabric) and available for perfume release when the capsules break by rubbing after drying.

Nonionic polysaccharide polymers are well known to those skilled in the art. Preferred nonionic polysaccharides are selected from the group consisting of locust bean gum, xyloglucan, guar gum, hydroxypropyl cellulose, and hydroxypropyl methylcellulose.

Cationic polymers are also well known to those skilled in the art. Preferred cationic polymers have a cationic charge density of at least 0.5meq/g, more preferably at least about 1.5meq/g, but also preferably less than about 7meq/g, more preferably less than about 6.2 meq/g. The cationic charge density of the cationic polymer can be determined by Kjeldahl method as described in the united states pharmacopeia in chemical tests for nitrogen determination. Preferred cationic polymers are selected from those units containing primary, secondary, tertiary and/or quaternary amine groups, which may form part of the main polymer chain or may be carried by a pendant substituent directly attached thereto. The cationic polymer preferably has a weight average molecular weight (Mw) of 10,000 to 2M daltons, more preferably 50,000 to 3.5M daltons.

According to a particular embodiment, cationic polymers based on acrylamide, methacrylamide, N-vinylpyrrolidone, quaternized N, N-dimethylaminomethacrylates, diallyldimethylammonium chloride, quaternized vinylimidazoles (3-methyl-1-vinyl-1H-imidazol-3-ium chloride), vinylpyrrolidone, acrylamidopropyltrimethylammonium chloride, cassia hydroxypropyltrimethylammonium chloride, guar hydroxypropyltrimethylammonium chloride or polygalactomannan 2-hydroxypropyltrimethylammonium chloride ether, starch hydroxypropyltrimethylammonium chloride and cellulose hydroxypropyltrimethylammonium chloride will be used. Preferably the copolymer should be selected from the group consisting of polyquaternium-5, polyquaternium-6, polyquaternium-7, polyquaternium 10, polyquaternium-11, polyquaternium-16, polyquaternium-22, polyquaternium-28, polyquaternium-43, polyquaternium-44, polyquaternium-46, cassia seed hydroxypropyltrimethylammonium chloride, guar hydroxypropyltrimethylammonium chloride or polygalactomannan 2-hydroxypropyltrimethylammonium chloride ether, starch hydroxypropyltrimethylammonium chloride and cellulose hydroxypropyltrimethylammonium chloride.

Specific examples of commercially available products includeSC60 (cationic copolymer of acrylamidopropyltrimethylammonium chloride and acrylamide, source: BASF) orSuch as PQ 11N, FC 550 or Style (polyquaternium-11-68 or a copolymer source quaternized with vinylpyrrolidone: BASF), or(C13S or C17, source Rhodia).

Polymer matrix

The polymer matrix as defined in the present invention is a water-soluble polymer matrix.

Any water-soluble polymer may be used for the purposes of the present invention.

For the purposes of the present invention, "water-soluble biopolymer" is intended to encompass any biopolymer that forms a one-phase solution in water. Preferably, it forms a one-phase solution when dissolved in water at a concentration of up to 20% by weight, more preferably even up to 50% by weight. Most preferably, it forms a one-phase solution when dissolved in water at any concentration.

Preferably, the water soluble polymer comprises a carbohydrate. For example, the water-soluble polymer comprises monosaccharides, oligosaccharides, and/or polysaccharides, wherein the prefixes "oligo" and "poly" are defined below.

In one embodiment of the invention, the water-soluble polymer comprises a monomeric, oligomeric or polymeric carrier material, or a mixture of two or more of these. The oligomeric carrier is a carrier, wherein 2-10 monomer units are connected through covalent bonds. For example, if the oligomeric carrier is a carbohydrate, the oligomeric carrier may be sucrose, lactose, raffinose, maltose, trehalose, fructooligosaccharides (fructo-oligosaccharides), to name a few.

Examples of monomeric carrier materials are e.g. glucose, fructose, mannose, galactose, arabinose, fucose, sorbitol, mannitol.

Polymeric vectors have more than 10 monomeric units linked by covalent bonds. Non-limiting examples of the latter include polyvinyl acetate, polyvinyl alcohol, dextrin, maltodextrin, natural or modified starch, vegetable gums, pectin, xanthan gum, alginates, carrageenan or cellulose derivatives, such as carboxymethyl cellulose, methyl cellulose or hydroxyethyl cellulose, and all materials commonly used today for encapsulating volatile substances. Preferably, the polymeric carrier comprises maltodextrin. Most preferably, it comprises maltodextrin and a modified starch, such as an alkenyl succinated starch.

The polymer matrix is preferably present in an amount of 25 to 50 wt.%, based on the total weight of the microparticle.

Fire-retardant agent

The pulverulent composition according to the invention is distinguished in that it contains a flameproofing agent comprising talc. In a particular embodiment, the fire retardant consists of talc.

According to another embodiment, talc is used in combination with another fire retardant selected from the group consisting of sodium carbonate, zeolite, sodium sulfate and mixtures thereof.

Without being bound by any theory, applicants believe that according to embodiments in which talc is present as a blend with the particulates, the talc may cover the particulate surfaces in the dust cloud, thus reducing the risk of explosion.

Thus, according to one embodiment, the average particle size of the talc is smaller than the average particle size of the microparticles. Preferably, the talc has an average particle size of 5 to 50 microns, preferably 10 to 20 microns.

Anti-caking agent

The powdered composition may comprise an anti-caking agent, preferably hydrophobic and/or hydrophilic silica, to increase the flowability of the powder.

Since the powdered composition shows good stability under humid conditions, only very small amounts or even no amounts of anti-caking agents are required.

According to a particular embodiment, the amount of anti-caking agent in the powdered composition is from 1 to 15% by weight, preferably from 2.5 to 10% by weight, based on the total weight of the composition.

According to another particular embodiment, the powdered composition does not contain any anti-caking agent.

Method for preparing a powdered composition

The embodiments described for the powdered composition are also applicable to the process for preparing the composition.

There are several options for preparing the powdered compositions defined in the present invention.

According to one embodiment, when the talc is present in a blend with the microparticles, the process for preparing the powdered composition comprises the following steps: a fire retardant comprising talc is dry blended with microparticles comprising a flavor oil or a flavor oil dispersed in a polymer matrix to form a powdered composition.

After dry blending, the talc covers the microparticles to prevent the risk of explosion of the microparticles during handling of the resulting powdered composition (in the form of a blend).

There is no limitation on the manner in which the dried microparticles are obtained.

Among those methods, spray drying, which is a well-known method for encapsulating active ingredients, can be cited, for example.

However, other drying methods can also be cited, such as extrusion, fluidized bed, or even drying at room temperature using materials (carriers, desiccants) that meet specific criteria (see, for example, WO 2017134179).

According to one embodiment, the composition comprises spray-dried microparticles obtained by a process comprising the steps of: spray drying an aqueous emulsion of a flavor oil or flavor oil in a water-soluble polymer.

More particularly, when the oily phase comprises at least one portion freely dispersed in the matrix, the dry microparticles are obtained by a process comprising the following steps:

(i) preparing an aqueous phase comprising a water-soluble polymer,

(ii) preparing an oil phase comprising a flavor oil or a flavor oil; and mixing the oil phase with the water phase to obtain an emulsion.

(iii) (iii) optionally mixing the emulsion of step (ii) with a microcapsule slurry comprising at least one microcapsule having an oil-based core and a polymeric shell; and is

(iv) (iv) drying, preferably spray drying, the slurry of step (iii) to obtain spray dried microparticles,

when the oily phase comprises at least one portion encapsulated in a matrix, the dry microparticles may be obtained by a process comprising the following steps:

(i) preparing an aqueous phase comprising a water-soluble polymer,

(ii) optionally, preparing an oil phase comprising a flavor oil or a flavor oil; and mixing the oil phase with the water phase to obtain an emulsion.

(iii) (iii) mixing the aqueous phase of step (i) or the emulsion of step (ii) with a microcapsule slurry comprising at least one microcapsule having an oil-based core and a polymeric shell; and is

(iv) (iv) drying, preferably spray drying, the slurry of step (iii) to obtain spray dried microparticles,

according to a particular embodiment, an anti-caking agent is added during and/or after step (iii) and/or step (iv) of the above process.

According to another embodiment, when talc is present in the microparticles, the process for preparing the powdered composition comprises the steps of: a fireproofing agent comprising talc is added to an aqueous emulsion of a flavor or flavor oil in a water-soluble polymer and the resulting emulsion is spray-dried to form a powdered composition.

The powdered composition obtained by the process described in the above embodiments is also an object of the present invention.

Method for reducing the explosive violence of a powdered composition

Another object of the invention is the use of talc in a powdered composition comprising microparticles made of a polymer matrix and a perfume or flavor oil dispersed in said matrix, for reducing the violence of the composition to explode during its operation.

Another object of the invention is a method of reducing the violence of an explosion of a powdered composition comprising microparticles made of a polymer matrix and a perfume or flavor oil dispersed in said matrix, comprising the steps of:

-adding a fire retardant comprising talc to the powdered composition, and/or,

-incorporating a fire retardant comprising talc in and/or within the particles of the powdered composition, and/or,

-blending a fire retardant comprising talc with the powdered composition.

Powdered consumer product

The microcapsules of the invention can be advantageously used in many fields of application and in consumer products. The microcapsules can be used in powder form, suitable for use in powdered consumer products.

Preferably in the form of a laundry care product, a home care product, a body care product, a skin care product, a hair care product, an air care product or a hygiene product, a consumer product comprising microcapsules as defined above, or a perfuming composition as defined above is also an object of the present invention.

Another object of the present invention is a powdered consumer product comprising

(a) 2 to 65% by weight, relative to the total weight of the consumer product, of at least one surfactant;

(b) a powdered composition as defined above.

(c) Alternatively, perfume powders other than microcapsules as defined above, which are also an object of the present invention.

According to a particular embodiment, the consumer product is selected from dry hair cleaners, talcum powder, powder detergents, detergent beads, solid fragrances, cat litter, powder hair dyes, antiperspirant compositions, deodorant (body perfuming) compositions.

Preferably, the consumer product comprises 0.05 wt%, preferably 0.1 to 15 wt%, more preferably 0.2 to 5 wt% of the powdered composition of the invention, these percentages being by weight relative to the total weight of the consumer product. Of course, the above concentrations can be adjusted according to the olfactory effect desired for each product.

The invention will now be illustrated by, but not limited to, the following examples.