Metal carboxylate and method of production thereof

Abstract

The present invention refers to a metal carboxylate for deodorizing applications obtained by reacting at least one hydrophilic compound with at least one carbonyl compound, to form an intermediate compound having at least one free carboxylic acid group, and subsequently adding at least one metal compound to said intermediate compound to form said metal carboxylate. The use of the metal carboxylate as an odor-inhibition agent in cosmetics, household products, detergents and in technical applications is further proposed. In addition, a method for producing the metal carboxylate is disclosed herein.

Description

[0001] Metal carboxylate and method of production thereof

[0002] FIELD OF THE INVENTION

[0003] The present invention relates to a metal carboxylate for deodorizing applications, a use of the metal carboxylate as a deodorizing agent and a method for producing said metal carboxylate.

[0004] TECHNICAL BACKGROUND

[0005] In many areas of daily life such as household, personal care, pet supplies, industrial and public areas, there is a need to suppress unpleasant odors.

[0006] One of many strategies against unpleasant odors is the use of deodorizing agents, which are chemically designed to bind to volatile molecules that cause bad odors. Hence, unpleasant odors are absorbed by deodorizing agents. Deodorizing agents are used in products such as body deodorants, hygiene products in general, room air fresheners, animal bedding, water treatment, air filters and the like.

[0007] Cyclodextrins are a well-known class of water-soluble materials that are capable of inhibiting unpleasant odors. In detail, cyclodextrins are oligosaccharides consisting of a macrocyclic ring of glucose subunits joined by a-1 ,4 glycosidic bonds. The macrocyclic ring enables cyclodextrins to capture volatile molecules within the molecular ring structure. However, there is the drawback that depending on the ring size, this capturing only works for specific types of volatile molecules. Further, at higher temperatures, cyclodextrins tend to release volatile molecules again, which means that the bad odors can then reappear. Another disadvantage of cyclodextrins is that cyclodextrins are not specifically absorbing volatile molecules. Hence, they also trap fragrant odors such as perfume molecules. In addition, cyclodextrins are relatively expensive to produce.

[0008] Another class of deodorizing agents are zinc soaps, of which zinc ricinoleate currently plays the most important role commercially. The effectiveness of zinc ricinoleate is comparatively unspecific with respect to absorbing volatile molecules. Zinc ricinoleate tends to bind to nitrogen-containing and sulfur-containing molecules which typically cause an unpleasant odor, whereas pleasant odors are not absorbed by zinc ricinoleate. Desorption processes are usually not found. Another advantage is the good accessibility of the precursor materials for preparing zinc ricinoleates. Carboxylic acids such as ricinoleic acid can also be obtained from sustainable sources.

[0009] However, one major drawback of zinc ricinoleates is that they are hardly soluble in water and are not effective as deodorizing agents in their undissolved form. This drawback can be addressed by using suitable additives such as solubilizers to incorporate zinc ricinoleate in water-based liquid formulations. Nevertheless, solubilizers may not be desired in any case and are increasing the costs and complexity of such formulations.

[0010] DE 10 160 933 A1 discloses formulations with deodorizing effect, the formulations containing zinc ricinoleate, amino acids with additional amino function, surfactants and glycols as solubilizers.

[0011] US 2009 / 0 092 568 A1 discloses an odor absorbing composition comprising a zinc salt of ricinoleic acid, a solubility promoter including sodium iminodisuccinate and water.

[0012] In DE 40 14 055 A1 , ethoxylated fatty alcohols and tertiary amines are used as solubilizers in corresponding formulations.

[0013] To achieve sufficient water solubility, an additional complexing agent can also be used explicitly, as shown in WO 2009 / 0 83 070 A2.

[0014] In addition to zinc ricinoleates, other zinc salts of carboxylic acids are known in the prior art which have odor-absorbing properties as well.

[0015] WO 2018087 147 A1 discloses zinc neodecanoate, which is also hardly water- soluble, and formulations based thereon using solvents such as isopropyl myristate.

[0016] DE 28 33 291 A1 discloses zinc or magnesium salts of polycarboxylic acids that are accessible by Diels-Alder reaction and are based, for example, on linoleic acid as starting material. The proposed zinc or magnesium salts of polycarboxylic acids are lipophilic products designed for use in creams, lotions, gels or sticks.

[0017] In contrast, water-soluble zinc salts of shorter-chain carboxylic acids, polyvalent carboxylic acids and hydroxycarboxylic acids, such as zinc glycolate, lactate, citrate, malonate or salicylate, have hardly any deodorizing properties. Rather, they are used as anti-viral or dermal agents against skin inflammations. Reference is made herein to WO 2021 / 260649 A1 , WO 98 / 51 275 A1 and EP 1 816 116 A1 which disclose such zinc salts.

[0018] Water-soluble zinc complexes with deodorizing properties that are not based on zinc ricinoleate are also known. For example, US 2007 / 0092461 A1 discloses metal amino acid hydroxy acid complexes of transition metal ions (e.g. Zn) that are effective in the treatment of skin conditions as well as against body odor. However, these zinc compounds can only be obtained as long-term stable concentrates having complicated formulations. Moreover, they leave visible residues after drying.

[0019] Another way to obtain water-soluble zinc compounds with deodorizing properties is the use of zinc salts of polyitaconic acid, as disclosed in US 2016 / 0 194 493 A1. However, the production of polyitaconic acid is technically demanding and associated with high-energy consumption.

[0020] Thus, there is a need to provide suitable deodorizing compounds that can be easily incorporated into aqueous formulations without using additional solubilizers and that exhibit good deodorizing properties for a wide range of volatile molecules causing unpleasant odor. In addition, such deodorizing compounds should be obtainable via an easy synthesis route. Furthermore, the starting materials for preparing such compounds should be inexpensive, widely available and sustainable. Moreover, such compounds should be toxicologically harmless and feature a good skin compatibility. In addition, when used in formulations, no visible stains should appear on textiles after application. SUMMARY OF THE INVENTION

[0021] Thus, it is an objective of the present invention to provide a deodorizing compound that overcomes at least one of the aforementioned issues of the prior art.

[0022] In a first aspect, the invention relates to a metal carboxylate for deodorizing applications wherein the metal carboxylate is obtainable by reacting at least one hydrophilic compound with at least one carbonyl compound to form an intermediate compound having at least one free carboxylic acid group and reacting the intermediate compound with at least one metal compound to form said metal carboxylate.

[0023] The at least one hydrophilic compound is selected from the group consisting of polyols, amino alcohols, protein hydrolysates, peptides, and polyamines.

[0024] The at least one carbonyl compound is selected from the group consisting of dicarboxylic acids, polycarboxylic acids and carboxylic acid anhydrides thereof as well as diacyl chlorides and polyacyl chlorides.

[0025] The at least one metal compound comprises a metal selected from the group consisting of elements of the boron group, alkaline earth metals and transition metals.

[0026] The metal carboxylate obtainable as described above has a carboxylate group originating from the carbonyl compound bound to a hydrophilic residue originating from the hydrophilic compound by means of a chemically stable ester bond or amide bond, and surprisingly exhibits deodorizing properties for various volatile compounds causing bad odor. Further, the metal carboxylate is also water-soluble due to the hydrophilic residue, which renders said metal carboxylate suitable for a wide range of applications without the need for additional solubilizers.

[0027] Further, the metal carboxylate can be easily produced using widely available, inexpensive and sustainable starting materials. As disclosed above, the metal carboxylate can be obtained in a two-step synthesis using basic chemical reactions. In a first step, a hydroxyl group or amine group of the hydrophilic compound is coupled to a carboxylate group of the carbonyl compound by esterification or amide formation. The first reaction step then yields the intermediate compound in the form of a carboxylic acid having a free carboxylic acid group, which is bound to the hydrophilic residue via an ester bond or an amide bond, depending on the nature of the starting hydrophilic compound. The free carboxylic acid group of the intermediate compound is subsequently reacted with the metal compound to obtain the metal carboxylate in a simple manner. The above process can be carried out without the need of advanced technical equipment. Hence, the metal carboxylate can be obtained in a cost-efficient manner based on inexpensive and easily available starting materials. In particular, since isolation of the intermediate compound is not necessary, the metal carboxylate can be obtained in a one-pot reaction without requiring a complex handling of the intermediate compound and the starting materials.

[0028] DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

[0029] According to the invention, the metal carboxylate for deodorizing applications is obtainable by reacting at least one hydrophilic compound with at least one carbonyl compound to form an intermediate compound having at least one free carboxylic acid group and reacting the intermediate compound with at least one metal compound to form said metal carboxylate.

[0030] In the following, the starting materials to form the metal carboxylate are described in more detail. The description of the starting materials is given by way of examples but should not be understood in a limiting sense.

[0031] COMPOUND (A): HYDROPHILIC COMPOUND

[0032] According to the invention, the hydrophilic compound (A) is selected from the group consisting of polyols, amino alcohols, protein hydrolysates, peptides, and polyamines.

[0033] Compound (A1): Polyol

[0034] A polyol is defined herein as an organic chemical compound which has at least two hydroxyl groups in the molecule.

[0035] The polyol may comprise an aromatic or aliphatic hydrocarbon backbone.

[0036] Preferably, suitable polyols comprise a linear, branched or cyclic, saturated or unsaturated hydrocarbon backbone. Optionally the hydrocarbon backbone is interrupted by one or more heteroatoms. Suitable heteroatoms are oxygen and nitrogen.

[0037] The polyol may contain further substituents such as sulfonates, sulfates or phosphates.

[0038] The hydrocarbon backbone of short-chain polyols for use in the present invention preferably has 2 to 10 carbon atoms, more preferably, 2 to 6 carbon atoms.

[0039] Suitable short-chain polyols are glycerol, glycol and propane diol.

[0040] Even more preferably, the polyol may be a long-chain polyol.

[0041] The hydrocarbon backbone of long-chain polyols for use in the present invention preferably has 11 to 32 carbon atoms, more preferably, 14 to 22 carbon atoms.

[0042] Suitable long-chain polyols are polyester polyols such as bis-diglyceryl polyacyladipate-2.

[0043] Alternatively, the polyol may be a polymeric polyol.

[0044] Examples of polymeric polyols are polyether polyols such as polyglycerol or derivatives thereof. In particular, compounds such as polyglycerol-3 caprate or polyglycerol succinate (polyester) may be used.

[0045] Examples for polyols having an aromatic hydrocarbon backbone are polyphenols such as tannins. For example, tannic acid may be used.

[0046] The polyol may also be a carbohydrate. Such polyols are in particular sustainable.

[0047] Carbohydrates which may be used as polyols are preferably selected from the group consisting of saccharides, hydrolysates of carbohydrates, preferably maltodextrin, fructans, and sugar alcohols, preferably sorbitol. Saccharides may be selected from monosaccharides and disaccharides, preferably sucrose, lactose, maltose, maltulose, isomaltose and isomaltulose, as well as oligosaccharides and polysaccharides, and combinations thereof.

[0048] More preferably, the carbohydrate is selected from the group consisting of sucrose and glucose. Compound (A2): Amino Alcohols

[0049] An amino alcohol is defined herein as an organic chemical compound which has at least one amino group and at least one hydroxy group.

[0050] In principle, any compound (A1) listed above may be amino functionalized, i.e. , by replacing at least one hydroxy group by one or more amino groups, or by simply adding one amino group, to yield the corresponding amino alcohol (A2).

[0051] Preferably, the amino alcohol may be a polymeric amino alcohol.

[0052] Preferably, suitable amino alcohols comprise a linear, branched or cyclic, saturated or unsaturated hydrocarbon backbone. Optionally, the hydrocarbon backbone is interrupted by one or more heteroatoms. Suitable heteroatoms are oxygen and nitrogen.

[0053] The amino alcohols can contain further substituents such as sulfates, sulfonates and phosphates. Preferably, the amino alcohols comprise a number of ethylene oxide units as hydrocarbon backbone having a number of 1 to 12 ethylene oxide units.

[0054] Suitable polymeric amino alcohols are polyether amino alcohols with ethylene glycol units such as 11-amino-3,6,9-trioxaundecanol which is available as Amino- dPEG®4-OH from Merck.

[0055] In particular, suitable amino alcohols may be any carbohydrates, such as polysaccharides, which are functionalized with at least one amino group.

[0056] Preferred examples of such functionalized polysaccharides are chitosan and chitosan hydrolysate.

[0057] Alternatively, polysaccharides such as aminoglycosides may be used.

[0058] Suitable aminoglycosides such as oligomeric glucosamines may be used.

[0059] Compound (A3) Peptides and protein hydrolysates

[0060] The hydrophilic compound may also be a peptide or a protein hydrolysate which are in particular sustainable and widely available.

[0061] A peptide is defined herein as a compound comprising 2 to 100 or more amino acids, which are held together by amide bonds. A protein hydrolysate is a mixture of the aforementioned peptides with varying amounts of amino acids of each peptide. Free amino acids may also be included in the protein hydrolysate.

[0062] Peptides are preferably selected from the group consisting of hydrolysates of proteins. A suitable hydrolysate is soy protein acid hydrolysate, which is available from Merck.

[0063] Protein hydrolysates are preferably derived from plant-based raw materials.

[0064] Compound (A4): Polyamines

[0065] A polyamine is defined herein as an organic chemical compound which has two or more amino groups.

[0066] The polyamine may comprise an aromatic or aliphatic hydrocarbon backbone.

[0067] Preferably, suitable polyamines comprise a linear, branched or cyclic, saturated or unsaturated hydrocarbon backbone. Optionally the hydrocarbon backbone is interrupted by one or more heteroatoms. Suitable heteroatoms are oxygen and nitrogen.

[0068] The hydrocarbon backbone of short-chain polyamines for use in the present invention preferably has 2 to 10 carbon atoms, more preferably, 2 to 6 carbon atoms.

[0069] Suitable short-chain polyamines are preferably selected from the group consisting of alkyl diamines and diamino acids.

[0070] For example, ethylene diamine or lysine may be used as suitable polyamines.

[0071] Optionally, the polyamine may comprise at least one hydroxy group resulting in the corresponding amino alcohol (A2).

[0072] COMPOUND (B): CARBONYL COMPOUND

[0073] According to the invention, the carbonyl compound is selected from the group consisting of dicarboxylic acids, polycarboxylic acids and carboxylic acid anhydrides thereof as well as diacyl chlorides and polyacyl chlorides. Mixtures of these compounds are also comprised of the term carbonyl compound. Accordingly, the carbonyl compound may have two, three, four, five or more carbonyl groups as part of respective carboxylic acid groups, diacyl chloride groups or carboxylic acid anhydrides.

[0074] The carbonyl compound (B) may be present in a reaction mixture together with the hydrophilic compound (A) as pre-synthesized starting reagent. Alternatively, the carbonyl compound (B) may be generated in situ before adding the hydrophilic compound or in the presence thereof.

[0075] Compound (B1): Cyclic carboxylic anhydride

[0076] Preferably, the carbonyl compound is a cyclic carboxylic anhydride.

[0077] More preferably, the carbonyl compound corresponds to a cyclic carboxylic anhydride of the following formula (I): wherein Z represents a hydrocarbon backbone.

[0078] The hydrocarbon backbone Z may be linear, branched or cyclic, saturated or unsaturated, and optionally the hydrocarbon backbone is interrupted by heteroatoms. Suitable heteroatoms are oxygen and nitrogen.

[0079] The hydrocarbon backbone preferably has 1 to 12 carbon atoms linking the carbonyl groups of the cyclic carboxylic anhydride, more preferably, 1 to 4 carbon atoms. More preferably, the carbon atoms linking the carbonyl groups of the cyclic carboxylic anhydride may form an alkyl chain or alkenyl chain.

[0080] Each carbon atom linking the carbonyl groups of the cyclic carboxylic anhydride can be saturated by one or two substituents why may be different or identical and are each independently selected from the group consisting of hydrogen atom, Ci- Cs alkyl group, C2-C10 alkenyl group, C2-C10 alkyl group, C6-C12 cycloalkyl group, C6-C12 aryl group, carboxyl group and combinations thereof. For the purposes of the invention, the term Ci-Cs alkyl includes linear or branched saturated hydrocarbon radicals having from one to eight carbon atoms. Preferred hydrocarbon radicals include, for example, methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, iso-butyl, tert-butyl, n-pentyl, iso-pentyl, 2,2- dimethylpropyl, n-hexyl, iso-hexyl, 2-ethylhexyl, n-heptyl, iso-heptyl, n-octyl and iso-octyl.

[0081] For the purposes of the invention, the term C2-C10 alkenyl includes linear or branched at least partially unsaturated hydrocarbon radicals having from two to ten carbon atoms, wherein the hydrocarbon radicals have at least one C-C double bond. Preferred hydrocarbon radicals include, for example, ethenyl, 1-propenyl, 2- propenyl, 1-n-butenyl, 2-n-butenyl, iso-butenyl, 1-pentenyl, 1-hexenyl, 1-heptenyl, 1-octenyl, 1-nonenyl and 1-decenyl.

[0082] For the purposes of the invention, the term C2-C10 alkyl includes linear or branched at least partially linear unsaturated hydrocarbon radicals having from two to ten carbon atoms, wherein the hydrocarbon radicals have at least one C-C triple bond. Preferred hydrocarbon radicals include, for example, ethynyl, 1-propynyl, 2- propynyl, 1-n-butynyl, 2-n-butynyl, iso-butynyl, 1-pentinyl, 1- hexynyl, 1-heptynyl, 1-octynyl, 1-nonynyl, and 1- decynyl.

[0083] For purposes of the invention, the term C6-C12 cycloalkyl includes cyclic, saturated hydrocarbon radicals having from six to twelve carbon atoms. Preferred hydrocarbon radicals include, for example, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclohexyl, cyclononyl and cyclodecanyl.

[0084] For purposes of the invention, the term C6-C12 aryl includes aromatic hydrocarbon radicals having from six to twelve carbon atoms. Preferred hydrocarbon radicals include, for example, phenyl, naphthyl and anthracyl.

[0085] Suitable cyclic carboxylic anhydrides are maleic anhydride, succinic anhydride, itaconic anhydride, citraconic anhydride, tricarballylic anhydride, acetyl glutamic anhydride, acetyl citric acid anhydride, glycolic acid anhydride, octenyl succinic anhydride, sebacic anhydride, O-di-acetyl tartaric anhydride and glutaric anhydride. In addition, corresponding tricarboxylic anhydrides such as aconitic anhydride may also be used.

[0086] The anhydride of succinic acid is particularly preferred. Compound (B2): Dicarboxylic or polycarboxylic acid

[0087] Alternatively, the carbonyl compound corresponds to a carboxylic acid of the following formula (II)

[0088] HOOC — Zn— COOH

[0089] (ID wherein Z represents a hydrocarbon backbone, and wherein n is 0 or 1.

[0090] The hydrocarbon backbone Z may be linear, branched or cyclic, saturated or unsaturated, optionally the hydrocarbon backbone is interrupted by heteroatoms. Suitable heteroatoms are oxygen and nitrogen.

[0091] The hydrocarbon backbone preferably has 1 to 12 carbon atoms linking the dicarboxylic acid groups, more preferably, 2 to 4 carbon atoms. More preferably, the carbon atoms linking the carboxylic acid groups may form an alkyl chain or alkenyl chain.

[0092] Each carbon atom can have one or two further substituents which are bonded thereto, respectively. The substituents may be identical or different and are each independently selected from the group consisting of hydrogen atom, Ci-Cs alkyl group, C2-C10 alkenyl group, C2-C10 alkyl group, C6-C12 cycloalkyl group, C6-C12 aryl group, hydroxide group, carboxyl group and amino group. Regarding to the selection of the alkyl, alkenyl, alkyl, cycloalkyl and aryl groups, reference is made to the above mentioned definitions for cyclic anhydrides which also applies here.

[0093] Suitable examples of dicarboxylic acids are succinic acid, oxalic acid, malonic acid, glutaric acid, adipic acid, pimelic acid and N-acetyl-L-glutamic acid, and itaconic acid.

[0094] Compound (B3): Diacyl or polyacyl chlorides

[0095] The diacyl or polyacyl chloride is at least difunctional with respect to the acyl chloride groups.

[0096] More preferably, the carbonyl compound corresponds to a diacyl chloride of the following formula (III) CIOC — Zn— COCI

[0097] (III) wherein Z represents a hydrocarbon backbone, and wherein n is 0 or 1.

[0098] The hydrocarbon backbone Z may be linear, branched or cyclic, saturated or unsaturated, optionally the hydrocarbon backbone is interrupted by heteroatoms. Suitable heteroatoms are oxygen and nitrogen.

[0099] The hydrocarbon backbone preferably has 1 to 12 carbon atoms linking the dicarboxylic acid groups, more preferably, 2 to 4 carbon atoms. More preferably, the carbon atoms linking the carboxylic acid groups may form an alkyl chain or alkenyl chain.

[0100] Each carbon atom can have one or two further substituents which are bonded thereto, respectively. The substituents may be identical or different and are each independently selected from the group consisting of hydrogen atom, Ci-Cs alkyl group, C2-C10 alkenyl group, C2-C10 alkyl group, C6-C12 cycloalkyl group, C6-C12 aryl group, and carboxyl group. Regarding to the selection of the alkyl, alkenyl, alkyl, cycloalkyl and aryl groups, reference is made to the above mentioned definitions for cyclic anhydrides which also apply here.

[0101] Suitable diacyl chlorides include adipoyl dichloride or sebacoyl dichloride.

[0102] COMPOUND (C): METAL COMPOUND

[0103] According to the invention, at least one metal compound is reacted with the intermediate compound having a free carboxyl group to form the metal carboxylate, wherein the metal is selected from the group consisting of elements of the boron group, alkaline earth metals and transition metals.

[0104] In principle, the anion of the metal compound is not limited and may be any suitable anion for the above metal which is known in the art to be replaced by a carboxylate group to form the metal carboxylate. Preferably, the metal compound is a metal oxide, hydroxide, carbonate, formate or acetate. The metal is selected from the group as defined above. Anions such as formates or acetates are preferably removed after the synthesis under vacuum.

[0105] One particular preferred example of a metal selected from the elements of the boron group is aluminum.

[0106] As a transition metal copper, iron, zinc, molybdenum, vanadium, manganese or zirconium may be used. Preferably, zinc is used as a transition metal.

[0107] Suitable examples for alkaline earth metals are magnesium and calcium.

[0108] For example, aluminum ch loro hydrate, calcium hydroxide, magnesium acetate, zinc oxide or a mixture thereof may be used as metal compounds.

[0109] Compound (C1): Zinc compound

[0110] It is preferred that the metal compound is a zinc compound which is selected from the group consisting of zinc oxide, zinc carbonate and zinc hydroxide, and mixtures thereof.

[0111] PROPERTIES OF THE METAL CARBOXYLATE

[0112] The metal carboxylate for deodorizing applications obtainable from the above described starting materials has one or more of the following properties:

[0113] - the metal carboxylate is miscible with water in any ratio, whereby the solubility of the metal carboxylate in aqueous media is at least 1% (w / w) related to the metal ion;

[0114] - the metal carboxylate has an average molecular weight Mn(number average) in a range from 200 g / mol to 1 ,000,000 g / mol.

[0115] Without wishing to be bound by theory, the metal carboxylate may be present in the form of a labile chelate complex which is capable to encage and bind volatile molecules having an unpleasant odor, and in particular volatile molecules having nitrogen or sulfur atoms. The stability of the said complex may be reduced by the high number of bridging atoms between Lewis donors and anionic carboxylate as a result of reduction of thermal movement of bond atoms. The resulting reduced stability of the said complex may facilitate ligand exchange with Lewis donor molecules, such as volatile odor molecules. At the same time, the hydrophilic compound incorporated in the metal carboxylate provides for a high solubility in water or other polar solvents. These effects together render the metal carboxylate suitable for a wide range of applications in aqueous solutions without the need for additional solubilizers.

[0116] USE OF THE METAL CARBOXYLATE

[0117] Therefore, according to a further aspect of the invention, the metal carboxylate according to the above-disclosed embodiments is used as a deodorizing agent in cosmetics, household products, detergents and in technical applications.

[0118] Deodorizing means that the metal carboxylate is capable to trap volatile molecules causing unpleasant odor, which leads to a decrease of the concentration of such volatile molecules in the ambient air. In contrast to fragrances, the metal carboxylate does not only mask or overlap the presence of said volatile molecules.

[0119] At the same time, fragrances are not affected by the deodorizing effect of the metal carboxylate.

[0120] According to a further embodiment, the metal carboxylate according to the invention is included in a deodorizing concentrate for deodorizing applications, the concentrate comprising the metal carboxylate according to the above-disclosed embodiments; and a polar solvent, preferably a solvent selected from the group consisting of water, short-chain, optionally polyhydric alcohols having 1 to 4 carbon atoms, glycols, glycol ethers, triglycerides, and mixtures thereof.

[0121] Since the concentrate is a liquid formulation, the metal carboxylate can be easily handled and used for range of applications. For example, a liquid formulation can be easier transported, stored and processed into further products.

[0122] Preferably, the metal carboxylate is completely dissolved without the need of any solubilizers. However, depending on the specific application, certain solubilizers may be included in the formulation to stabilize and / or increase the solubility of the metal carboxylate and / or other compounds.

[0123] In the deodorizing concentrate, the metal carboxylate may have a concentration of 0.1 mol / L to 8 mol / L, preferably 0.1 mol / L to 1.5 mol / L, with respect to the total volume of the concentrate. For application by the end user, the concentration of the metal carboxylate in the formulation can be adjusted in a range of from 3 mmol / L to 0.1 mol / L.

[0124] The polar solvent preferably comprises at least one of water, glycol, glycol ether, and mixtures thereof. More preferably, the polar solvent comprises water, and the metal carboxylate is in an aqueous formulation.

[0125] According to another embodiment, the deodorizing concentrate has a pH in a range of 4 to 10, including the skin neutral pH range. This pH range renders the concentrate suitable for the application in body care products, in particular skin care products. Even more preferably, the pH is in the range of 5.5 to 7.5.

[0126] The concentrate may further comprise any fragrances known in the art, such as commercially available soap perfumes such as Meeresfrisch PCMF AF (Dullberg Konzentra GmbH & Co. KG). Since the metal carboxylate is specific towards certain types of volatile molecules, in particular towards molecules containing sulfur atoms or nitrogen atoms, fragrant substances are not likely to be absorbed by the metal carboxylate. Hence, fragrant substances and the metal carboxylate can be used within the same concentrate without interfering with each other.

[0127] METHOD FOR PRODUCING THE METAL CARBOXYLATE

[0128] According to a further aspect of the invention, a method for producing the metal carboxylate is disclosed, wherein the method comprises the steps of: a) providing the hydrophilic compound selected from the group consisting of polyols, amino alcohols, protein hydrolysates, peptides, and polyamines, and optionally heating of the hydrophilic compound; b) combining the hydrophilic compound with the at least one carbonyl compound, the carbonyl compound being selected from the group consisting of dicarboxylic acids, polycarboxylic acids and carboxylic acid anhydrides thereof, as well as diacyl chlorides and polyacyl chlorides, and reacting the hydrophilic compound and the carbonyl compound to form the intermediate compound having at least one free carboxylic acid group; and c) reacting the intermediate compound with at least one metal compound, wherein the metal is selected from the group consisting of the boron group, alkaline earth metals and transition metals, to form the metal carboxylate.

[0129] Preferably, the metal compound is a zinc compound selected from the group consisting of zinc oxide, zinc carbonate, zinc hydroxide and mixtures thereof.

[0130] Further, at least one of steps a) to c) can be carried out solvent-free, which means without adding an inert solvent.

[0131] According to another embodiment, step c) is carried out with the addition of a polar solvent preferably selected from the group consisting of water, short-chain alcohols, optionally polyhydric alcohols, having 1 to 4 carbon atoms, glycols, glycol ethers, triglycerides and mixtures thereof.

[0132] Prior to step a), an additional step may be carried out, in which the carbonyl compound can be prepared in-situ. Preferably, the carbonyl compound is prepared in the presence of the hydrophilic compound. More preferably, the cyclic carboxylic anhydride is prepared in-situ.

[0133] For example, the cyclic carboxylic anhydride may be obtained by reacting a dicarboxylic acid and a carboxylic anhydride.

[0134] EXAMPLES

[0135] Compounds used in the examples:

[0136] Hydrophilic compound (A) - Polyols (A1)

[0137] Polyglycerol-3 (A 1.1)

[0138] - Sucrose (A 1.2)

[0139] - Maltodextrin (A 1.3)

[0140] Propanediol (A 1.4)

[0141] - Tannic acid (A 1.5)

[0142] Polyglycerol-3 caprate (A 1 .6)

[0143] Polyglycerol succinate (polyester) (A 1.7)

[0144] Hydrophilic compound (A) - Amino alcohol (A2)

[0145] - Glucosamine (A 2.1) Hydrophilic compound (A) - Peptides, protein hydrolysates (A3)

[0146] - Soy protein acid hydrolysate (A 3.1)

[0147] Hydrophilic compound (A) - Polyamines (A4)

[0148] Ethylene diamine (A 4.1)

[0149] Lysine (A 4.2)

[0150] Carbonyl compound (B)

[0151] Carbonyl compound (B) - Cyclic carboxylic anhydride (B1)

[0152] - Succinic anhydride (B 1.1)

[0153] N-Acetyl glutamic anhydride (B 1.2)

[0154] - Glycolic acid anhydride (B 1 .3)

[0155] - O-Di-acetyl tartaric anhydride (B 1.4)

[0156] - Octenyl succinic anhydride (B 1.5)

[0157] Itaconic anhydride (B 1.6)

[0158] - O-Acetyl citric anhydride (B 1.7)

[0159] - Maleic anhydride (B 1.8)

[0160] - Sebacic anhydride (B 1.9)

[0161] Carbonyl compound (B) - Dicarboxylic acid (B2)

[0162] - Succinic acid (B 2.1)

[0163] Carbonyl compound (B) - Diacyl chloride (B3)

[0164] - Adipoyl dichloride (B 3.1)

[0165] Metal compound (C)

[0166] - Zinc oxide (C1)

[0167] - Aluminum chlorohydrate (C2)

[0168] - Calcium hydroxide (C3)

[0169] - Magnesium acetate (C4)

[0170] Unless otherwise noted, the following examples have been carried out at room temperature (25 °C). Water used in the examples is deionized water.

[0171] Synthesis of the metal carboxylate

[0172] The synthesis of the metal carboxylate according to the invention is demonstrated by the following examples 1 and 3 - 24. Example 1 - Zinc polyqlycerol-3 succinate:

[0173] In a beaker equipped with a magnetic stirrer and hot plate, 15 g of polyglycerol- 3 is heated to 120°C. Thereafter, 15 g of succinic anhydride is added and stirred. After the mixture turned clear, the solution is cooled to 80 °C and stirred for one hour to obtain polyglycerol-3 succinate. Then 5 g of zinc oxide is added and stirred until complete dissolution indicating that the chemical conversion of zinc oxide is complete.

[0174] The viscosity of the mixture can be reduced by additional addition of water or glycerol.

[0175] Example 2 - Deodorizing concentrate:

[0176] 5 g of zinc polyglycerol-3 succinate from example 1 is mixed with an additional amount of 1.5 g polyglycerol-3 succinate and 10 ml of water, and then the pH is adjusted with potassium hydroxide solution to the desired pH between 5.5 and 7.5 whilst stirring. A clear, low viscosity solution is obtained which shows low foaming ability and is suitable for spray applications. 1 ml of the concentrate vs. 1 ml of deionized water (blank sample) are sprayed onto black cotton fabric. The fabric is dried at room temperature. The concentrate does not show light stains on the fabric.

[0177] Example 3 - Zinc sucrose succinate:

[0178] In a single-neck flask, 16 g sucrose, 5 g polyglycerol-3 and 5 ml fully demineralized water are placed and dissolved at 100 °C. The water is then completely removed under vacuum. The flask is then fitted with a stirrer and heated to 100 °C on a hot plate with an oil bath. 14.5 g of succinic anhydride is added subsequently, and the solution is brought to 120 °C for a short time until the solids are dissolved. The temperature of the mixture is then lowered to 80 °C, and the clear solution is stirred for one hour. Thereafter, 20 g glycerol and 4.8 g zinc oxide are added and stirred until the solution was clear. The pH value is adjusted to 7 with diluted sodium hydroxide.

[0179] Example 4 - Zinc maltodextrin succinate:

[0180] In a single-neck flask, 15 g of maltodextrin (Maltodextrin 19 from Nutricia Milupa GmbH, Maltodextrin 19 having a dextrose equivalent of 18 - 20), 15 g of polyglycerol-3 and 5 ml of demineralized water are placed and dissolved at 100°C. The water is then completely removed under vacuum. The flask is then equipped with a stirrer and heated to 100 °C on a hot plate with an oil bath. 15 g of succinic anhydride is added subsequently, and the solution is brought to 120 °C for a short time until the solids are dissolved. The clear solution is then stirred for one hour. Thereafter, 20 g of glycerol and 5 g of zinc oxide are added and stirred until the solution was clear. The pH value was adjusted to 7 with diluted sodium hydroxide.

[0181] Example 5 - Zinc polyglvcerol-3 N-acetylglutamate

[0182] 10.4 g of monosodium glutamate is added to 10 g of acetic anhydride and 0.1 g of concentrated sulfuric acid and the obtained mixture is slowly heated to 120 °C while stirring. A further 20 g of acetic anhydride is slowly added through a dropping funnel. The reaction mixture is then stirred for 30 minutes at 125 °C. From the reaction the carbonyl compound N-acetyl glutamic anhydride is obtained in-situ. The acetic acid is removed under vacuum (20 mbar, 2.5 h) at 120°C. Then, 16.5 g of polyglycerol-3 is added and the obtained mixture is stirred at 120 °C for 2 h. Afterwards, 8.3 g of the obtained mixture is mixed with 15 ml water and 200 mg of zinc oxide is added thereto. The pH value is adjusted to 7 with diluted sodium hydroxide solution.

[0183] Example 6 - Zinc 1 ,2-propanediol succinate

[0184] 4 g of succinic anhydride is added to 6 ml of 1 ,2-propanediol and then heated to 110 °C and stirred at this temperature for 1 hour. Then, 0.75 g of zinc oxide in 10 ml water is added to the mixture and the pH value of the mixture is adjusted by using diluted sodium hydroxide solution to a pH of 7.

[0185] Example 7 - Zinc polyglycerol-3 diglycolate

[0186] 10.2 g of diglycolic acid is added to 10 g of acetic anhydride and the obtained mixture is then heated to 100°C while stirring. Subsequently, 0.5 g of pyridine is added and then a further 25 g of acetic anhydride. The mixture is stirred for 1 h to obtain in-situ the carbonyl compound diglycolic anhydride. Subsequently, the acetic acid is removed under vacuum (20 mbar, 1 h) at 120 °C and 20 ml of glacial acetic acid is added thereto and also removed under vacuum (20 mbar, 2.5 h) at 120°C. Then, 15 g of polyglycerol-3 is added and the obtained mixture is stirred at 120 °C for 1 h. Afterwards, 12 g of the mixture is added and dissolved in water with 700 mg of zinc oxide. The pH value is adjusted to a pH of 5.8 with diluted sodium hydroxide solution.

[0187] Example 8 - Zinc polyglycerol-3 di-O-acetyl tartrate

[0188] 10 g of tartaric acid is mixed with 10 g of acetic anhydride and then 0.01 g of concentrated sulfuric acid is added. The solution is slowly heated to 100 °C, then a further 25 g of acetic anhydride is gradually added. The solution is stirred for 3 h at 120 °C to obtain in-situ the carbonyl compound di-O-acetyl tartaric anhydride. Afterwards, the acetic acid and acetic anhydride are removed under vacuum (20 mbar, 2.5 h) at 120 °C. Then, 15 g of polyglycerol-3 is added and the obtained mixture is stirred at 120 °C for 1 h. 12 g from this mixture is dissolved in water with 700 mg of zinc oxide. The pH value is adjusted to 6.5 with diluted sodium hydroxide solution.

[0189] Example 9 - Zinc tannin succinate

[0190] 8 g of tannic acid is dissolved in 15 ml of pyridine. Then, 4 g of succinic anhydride is added thereto and the obtained solution is stirred for 2 h at 110 °C. Then, 30 ml of water is added and the solution is concentrated under vacuum. This process is repeated three times. The obtained solid is dissolved in 10 ml of water and 0.75 g of zinc oxide is added and dissolved with stirring. The pH value is adjusted to a pH of 7 with diluted sodium hydroxide solution.

[0191] Example 10 - Aluminum polyglycerol-3 succinate

[0192] 5.5 g of polyglycerol-3 succinate (see Example 1) is mixed with 10 ml of water. Then, 350 mg aluminum chlorohydrate (available as Aloxicoll SD 100 from Elementis PLC) is added and dissolved. The pH value is adjusted to a pH of 7 with diluted sodium hydroxide solution.

[0193] Example 11 - Calcium polyglycerol-3 succinate

[0194] 5.5 g of polyglycerol-3 succinate (see Example 1) is provided and 1 g of lime milk, corresponding to 300 mg calcium hydroxide, is added thereto with 10 ml water and stirred until a clear solution is obtained. The pH value is adjusted to a pH of 7 with diluted sodium hydroxide solution. Example 12 - Magnesium polyqlycerol-3 succinate

[0195] 5.5 g of polyglycerol-3 succinate (see Example 1) is provided and 350 mg of magnesium acetate in 5 ml water is added thereto. Water and acetic acid are then removed under vacuum. Thereafter, 10 ml of water is added and the pH is adjusted to a pH of 7 with diluted sodium hydroxide solution.

[0196] Example 13 - Zinc polyglycerol-3 caprate succinate

[0197] 8 g of polyglycerol-3 caprate and 2 g of succinic anhydride are added and then heated to 110 °C for 2 hours whilst stirring. After cooling, 460 mg of zinc oxide in 10 ml of water is added and the obtained mixture is stirred until a clear solution is obtained. The pH value is then adjusted to a pH of 7 with diluted sodium hydroxide solution.

[0198] Example 14 - Zinc polyglycerol-3 adipate

[0199] 5 g of polyglycerol-3 is added and dissolved in 40 ml pyridine. Thereafter, 20 g of adipoyl dichloride is slowly added thereto while stirring. The reaction mixture is slowly heated and stirred at 80 °C for 2 hours. Then, 2 ml of water is slowly added to the mixture which is stirred for further 30 min. The supernatant is decanted and pyridine is removed under reduced pressure. 3 g of the obtained product is mixed with 320 mg of zinc oxide in 2 ml of water. The pH is then adjusted to a pH of 7 with diluted sodium hydroxide solution.

[0200] Example 15 - Zinc polyglycerol-3 octenyl succinate

[0201] 4 g of octenyl succinic anhydride is added to 4 g of polyglycerol-3 (see Example 1) and stirred at 60°C for 8 h. Then, 370 mg zinc oxide in 10 ml water is added thereto and the obtained mixture is stirred until a clear solution is obtained. The pH value is then adjusted to 7 with diluted sodium hydroxide solution.

[0202] Example 16 - Zinc ethylene diamine succinate

[0203] 2.6 g of succinic anhydride and 18 ml of ethylene diamine are mixed with each other and the obtained mixture is heated slowly while stirring. The so obtained clear solution is stirred at 110°C for 30 min. After heating, the excess ethylene diamine is removed under vacuum. Then, 0.5 g of zinc oxide in 20 ml water is added and the pH is neutralized with dilute hydrochloric acid and stirred until a clear solution has formed. Example 17 - Zinc polyqlycerol-3 itaconate

[0204] 5 g of polyglycerol-3 and 5 g of itaconic anhydride are mixed with each other and heated while stirring. After 2 h at 110°C, the mixture is cooled to room temperature and 0.8 g of zinc oxide in 10ml water is added thereto. The pH value is then adjusted to a pH of 7 with diluted sodium hydroxide solution.

[0205] Example 18 - Zinc polyqlycerol-3 O-acetylcitrate

[0206] 15 g of citric acid monohydrate is added to 35 g of acetic anhydride and then stirred at 110°C for 2 hours to obtain in-situ the carbonyl compound O-acetyl citric anhydride. Acetic acid and the excess acetic anhydride are then removed under vacuum at 110°C. Thereafter, 15 g of polyglycerol-3 is added and the obtained mixture is heated very slowly until a homogeneous phase has formed. The mixture is then stirred at 100°C for 2 hours. 3 g of the obtained intermediate is suspended after stirring with 700 mg of zinc oxide in 7 ml of water and stirred until a clear solution has formed. The pH value is then adjusted to a pH of 7 with diluted sodium hydroxide solution.

[0207] Example 19 - Zinc polyqlvcerol-3 malate

[0208] 3 g of polyglycerol-3 and 3 g of maleic anhydride are added and then slowly heated to 110°C. After a clear mixture as formed, the solution is cooled to 80°C and stirred for one hour. Then, 1 g of zinc oxide in 4 ml of water is added and the obtained mixture is stirred until the zinc oxide is completely dissolved. The pH value is adjusted to a pH of 7 with diluted sodium hydroxide solution.

[0209] Example 20 - Zinc lysine succinate

[0210] 5 g of L-lysine monohydrochloride is mixed with 4 g of succinic anhydride and 20 ml of pyridine is added thereto and the obtained mixture is slowly heated to 80°C while stirring. The supernatant is decanted and the solvent is removed under reduced pressure to form the intermediate. Then, 0.8 g of zinc oxide in 8 ml of water is added to the intermediate and the obtained mixture is stirred until the zinc oxide is completely dissolved. The pH value is adjusted to a pH of 7 with diluted sodium hydroxide solution.

[0211] Example 21 - Zinc polyqlycerol-3 sebacate

[0212] 10 g of sebacic acid dichloride is added to 20 ml of pyridine and the obtained mixture is stirred while 12 g of sebacic acid and 25 ml of n-hexane are added thereto. The obtained solution is stirred at 70°C for 2 h and then cooled and allowed to rest. After 2.5 h, the supernatant is decanted and transferred to a flask to remove the solvent at reduced pressure to obtain in-situ the carbonyl compound sebacic anhydride. 5 g of the solvent-free sebacic anhydride is then removed and slowly heated with 17 g of polyglycerol-3. The solution obtained therefrom is then stirred at 100°C for 3 hours. 5 g of the prepared polyglycerol sebacate is mixed with 300 mg zinc oxide in 8 ml water and dissolved with gentle heating. The pH value of the solution is then adjusted to a pH of 6.5 with diluted potassium hydroxide solution.

[0213] Example 22 - Zinc polyglycerol succinate (polyester)

[0214] 10 g of glycerol, 26 g of succinic acid and 0.25 g of hydrochloric acid (37%) are provided in a one-necked flask and are heated to 180°C while stirring until no more water separation is visible, wherein polyglycerol succinate as a hyperbranched polyester with free carboxylic groups is formed in-situ. The excess succinic acid is then removed under vacuum. The polyglycerol succinate (polyester) is cooled to approx. 100°C and 10 ml of water is added and then cooled further. Then, 2 g of zinc oxide in 5 ml of water is added and dissolved. The pH value is adjusted to a pH of 7 with sodium hydroxide solution.

[0215] Example 23 - Zinc protein hydrolysate succinate

[0216] Soy protein acid hydrolysate is dried over phosphorus pentoxide for 2 weeks. Then, 5 g of the dried hydrolysate is mixed with 1.5 g of succinic anhydride and 25 ml pyridine. The obtained mixture is stirred at 110°C for 2 hours. Pyridine is removed under vacuum and water is added several times and also removed under vacuum. Then, 0.3 g of zinc oxide in 3 ml of water is added thereto and the pH is adjusted to a pH of 6.5 with diluted sodium hydroxide solution.

[0217] Example 24 - Zinc glucosamine succinate

[0218] 2 g of glucosamine hydrochloride and 10 ml of pyridine are added in a singlenecked flask. Subseguently, 0.9 g of succinic anhydride is added thereto, and the obtained mixture is slowly heated to 110°C while stirring for 2 hours. The obtained solution is cooled slowly, and the formed supernatant is decanted. The solvent is then removed under reduced pressure and water is added and also removed under reduced pressure. Afterwards, 2 g of the intermediate is mixed with 120 mg of zinc oxide in 0.4 ml of water and the mixture is stirred until a clear solution has formed. The pH value is then adjusted to 6.5 with diluted sodium hydroxide solution.

[0219] Deodorizing tests

[0220] Preparation of stock solutions:

[0221] In a sample vial, 5 mg of skatole and 5 ml of ethanol are placed and mixed well. Then 0.3 ml of this solution are mixed with 250 ml of water. In addition, a 1% (w / w) ammonia solution and a 1 % (w / w) butyric acid solution are prepared.

[0222] Performing odor deodorizing tests with metal carboxylate of example 2:

[0223] 1 g of the solution from Example 2 is added to three 150 ml beakers and 10 ml of water. Thereafter, 0.5 ml of the stock solutions is added to each beaker. The beakers are first mixed well, then covered and allowed to stand for 1 h. Afterwards, no odor can be perceived.

[0224] If the tests are repeated without adding the solution from example 2 (blind sample), on the other hand, the respective odor of skatole was clearly perceptible.

[0225] In the same way, tests are carried out with a commercially available odor absorber for spray applications, based on modified p-cyclodextrin (Febreze Fabric Refresher from Procter & Gamble Company; reference sample) using an ammonia solution, butyric acid solution and skatole.

[0226] The results are summarized in the following table:

[0227] Table 1. Deodorizing tests

[0228] Odor reduction performance tests:

[0229] An odorizing stock solution consisting of thioglycolic acid as a model compound for thio compounds (1 wt.%); pyridine as a model compound for basic heterocycles (0.25 wt.%) and skatole as a heterocyclic compound with an extremely low odor threshold (0.1 % of the described ethanolic skatole solution) is prepared as an aqueous solution.

[0230] 2 g of the respective solution from the examples 1 , 3 - 24, is provided in a 100 ml screw-top jar and 17 g of water is subsequently added thereto. The mixture is mixed well. Then, 1 ml of the odorizing stock solution is added by using a pipette and the obtained solution thoroughly mixed and stored in closed screw-top jar for 1 h. Three odor tests are carried out on each of the individual samples after 1 h and compared with the blank sample. The results are summarized in table 2.

[0231] As it can be retrieved from the odor reduction test results, all of the tested metal carboxylates reduce the perception of bad smelling odor throughout the odorizing stock solutions. In contrast to this, odor from the reference sample was clearly perceptible.

[0232] Further, it is demonstrated that the odor reduction is achieved by using aluminum (Example 10), calcium (Example 11), magnesium (12) and zinc (Examples 1 , 3 - 9, 13 - 24) as metal ions. Notably, the most efficient odor reduction is achieved by using zinc ions for forming the metal carboxylate.

[0233] The carbonyl compound can be added as a pre-formed starting reagent to the hydrophilic compound. However, as seen from Examples 5, 7, 8, 18, 21 and 22, the carbonyl compound can also be prepared in-situ, either subsequent before adding the hydrophilic compound or in presence of the hydrophilic compound. In principle, the cyclic carboxylic anhydride (B1) can be obtained by reacting a dicarboxylic acid and a carboxylic anhydride together.

[0234] Example 15 shows that the intermediate product from a carbonyl compound and a hydrophilic compound can also be used as a polyol compound (A1). Table 2. Odor reduction tests

[0235]

Claims

Claims1. A metal carboxylate for deodorizing applications, wherein the metal carboxylate is obtainable by reacting at least one hydrophilic compound with at least one carbonyl compound to form an intermediate compound having at least one free carboxylic acid group, and reacting the intermediate compound with at least one metal compound to form said metal carboxylate, wherein the at least one hydrophilic compound is selected from the group consisting of polyols, amino alcohols, protein hydrolysates, peptides, and polyamines, wherein the at least one carbonyl compound is selected from the group consisting of dicarboxylic acids, polycarboxylic acids and carboxylic acid anhydrides thereof as well as diacyl chlorides and polyacyl chlorides, and wherein the at least one metal compound has a metal selected from the group consisting of elements of the boron group, alkaline earth metals and transition metals.

2. The metal carboxylate according to claim 1, wherein the metal compound is an aluminum, calcium, magnesium, zirconium or zinc compound, preferably a zinc compound selected from the group consisting of zinc oxide, zinc carbonate, zinc hydroxide, and mixtures thereof.

3. The metal carboxylate of claim 1 or 2, wherein the hydrophilic compound is selected from the group of polyols, amino alcohols, peptides and protein hydrolysates, polyamines and combinations thereof.

4. The metal carboxylate according to claim 3, wherein the hydrophilic compound is a polyol selected from the group consisting of polyetherpolyols, carbohydrates, and mixtures thereof.

5. The metal carboxylate according to claim 4, wherein the carbohydrates are selected from the group consisting of monosaccharides and disaccharides, preferably sucrose, glucose, lactose, maltose, maltulose, isomaltose and isomaltulose, as well as oligosaccharides and polysaccharides, and combinations thereof.

6. The metal carboxylate according to any one of the preceding claims, wherein the at least one carbonyl compound is a cyclic carboxylic anhydride.

7. The metal carboxylate of claim 6, wherein the cyclic carboxylic anhydride is selected from the group consisting of maleic anhydride, succinic anhydride, itaconic anhydride, citraconic anhydride, tricarballylic anhydride, and glutaric anhydride.

8. The metal carboxylate according to any one of the preceding claims, wherein the at least one carbonyl compound corresponds to a carboxylic acid of the following formula (II)HOOC — Zn— COOH(ID wherein Z represents a hydrocarbon backbone, and wherein n is 0 or 1.

9. The metal carboxylate according to any one of the preceding claims, wherein the at least one carbonyl compound corresponds to a diacyl chloride of the following formula (III)CIOC — Zn— COCI(III) wherein Z represents a hydrocarbon backbone, and wherein n is 0 or 1 .

10. The metal carboxylate of claim 8 or 9, wherein the hydrocarbon backbone Z comprises a linear, branched or cyclic, saturated or unsaturated, optionally heteroatom-substituted hydrocarbon backbone, preferably wherein the hydrocarbon backbone has a chain of 1 to 12 carbon atoms linking the carboxylic acid or acyl chloride groups, more preferably a chain of 2 to 4 carbon atoms.

11. The metal carboxylate according to any one of the preceding claims, characterized in that the metal carboxylate has one or more of the following features: the metal carboxylate is miscible with water in any ratio, whereby the solubility of the metal carboxylate in aqueous media is at least 1% (w / w) related to the metal ion;the metal carboxylate has an average molecular weight Mn(number average) in a range from 200 g / mol to 1 ,000,000 g / mol.

12. Use of the metal carboxylate according to any one of the preceding claims as a deodorizing agent in cosmetics, household products, detergents and in technical applications.

13. A method for producing the metal carboxylate of any one of preceding claims 1 to 11, wherein the method comprises the steps of: a) providing the hydrophilic compound selected from the group consisting of polyols, amino alcohols, protein hydrolysates, peptides, and polyamines, and optionally heating of the hydrophilic compound; b) combining the hydrophilic compound with the at least one carbonyl compound, the carbonyl compound being selected from the group consisting of dicarboxylic acids, polycarboxylic acids and carboxylic acid anhydrides thereof, as well as diacyl chlorides and polyacylchlorides, and reacting the hydrophilic compound and the carbonyl compound to form the intermediate compound having at least one free carboxylic acid group; and c) reacting the intermediate compound with at least one metal compound, wherein the metal is selected from the group consisting of elements of the boron group, alkaline earth metals and transition metals, to form the metal carboxylate.

14. The method for producing the metal carboxylate according to claim 13, wherein the method at least one of steps a) to c) is carried out solvent-free.

15. The process for preparing the metal carboxylate according to claim 13 or 14, wherein step c) is carried out with the addition of a polar solvent preferably selected from the group consisting of water, short-chain, optionally polyhydric, alcohols having 1 to 4 carbon atoms, glycols, glycol ethers, triglycerides and mixtures thereof.

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