Transparent aqueous fragrance composition

Abstract

Clear aqueous fragrance microemulsion compositions are provided that include a fragrance, a sorbosurfactant, an ionic surfactant, optionally a nonionic surfactant, and water. The sorbosurfactant includes at least one monoalkyl glycerol ether having the formula R-O-CH2-CH(OH)-CH2OH, where R is selected from the group consisting of C8-C12 unbranched alkyl and C6-C7 unbranched terminal alkenyl. The aqueous fragrance microemulsions are stable and may be used in their concentrated form or diluted with water depending on the end use application.

Description

[Technical field]

[0001] The present invention relates generally to aqueous fragrance compositions, and more particularly to clear aqueous fragrance microemulsion compositions. [Background technology]

[0002] Traditionally, perfumes are provided dissolved in a suitable solvent, typically a lower aliphatic alcohol, such as ethanol, isopropanol, propylene glycol, glycol ethers, and other organic solvents, as well as mixtures of such solvents with water. Fragrances intended for application to the skin are often dissolved in ethanol or ethanol / water mixtures with a high ethanol content.

[0003] Ethanol and other lower aliphatic alcohols have several disadvantages as fragrance solvents. They are volatile and flammable, thus posing a fire hazard in manufacture and use. They are relatively expensive and are not completely harmless to health. Ethanol, which is most acceptable from a health point of view, is heavily taxed in many countries and is not permitted in some Islamic countries for religious reasons. Furthermore, ethanol and lower aliphatic alcohols have distinct odors that can interfere with perfumes.

[0004] It would therefore be advantageous to substantially eliminate these alcohols as perfume solvents and replace them instead with water, which is cheap, non-toxic, non-flammable and odorless. However, most perfumes are substantially immiscible with water, and therefore such mixtures would necessarily be emulsions. To be suitable for applications where alcoholic solutions have traditionally been used, such emulsions should be thermodynamically stable and substantially transparent, and therefore "microemulsions."

[0005] Perfume microemulsions in water that contain no or a small amount of ethanol are known in the art. However, the inherent hydrophobicity of most perfumes requires the presence of significant amounts of surfactants as solubilizers. The surfactants found to be suitable in the art for solubilizing perfumes in water have been anionic or mixtures thereof with small amounts of nonionics. Thus, JM Blakeway et al, Int. J. Cosmet. Sc. 1, (1979), 1-15, describe microemulsions containing up to 4% w / w perfume in water where at least three times the amount of sodium lauryl ether sulfate, monoethanolamine lauryl sulfate, or a combination thereof, with a small amount of coconut diethanolamide, was required to obtain a clear microemulsion. TJ Lin, Surfactants in Cosmetics, Surfactants Sci. Ser. Vol. 16, (1985), 29-52, notes that to prepare practical o / w microemulsions, the weight ratio of surfactant to oil must be much greater than unity.

[0006] GB2190681A, EP0316726A and EP0368146A all describe transparent aqueous perfume microemulsions for hard surface cleaning purposes. Although very broad theoretical limits for perfume, anionic surfactant and nonionic surfactant content are suggested, the disclosed examples only demonstrate a substantial excess of surfactant relative to the amount of perfume. Most examples specify a surfactant / perfume ratio of 7:1, with one specifying 7:3. The anionic / nonionic surfactant ratio is 4:3 in all examples. Additionally, an organic solvent such as a water-soluble lower alkanol of 2-4 carbon atoms is preferably added as a so-called auxiliary surfactant (co-surfactant).

[0007] Expired US Patent No. 4,170,655 discloses clear, stable aqueous solutions of fat-soluble perfumes using certain hydroxyalkyl ester and / or N-(hydroxyalkyl)amide-ethoxylates at concentrations of 0.1-20 wt%, preferably 0.5-5 wt%, to solubilize 0.1-1 wt% of perfume in the aqueous solution. Similarly, expired US Patent No. 4,299,737 discloses the use of hydroxyalkyl ether-propoxy ethoxylates in the same relative amounts for the same purpose. In both of these expired US patents, surfactant / perfume ratios of 7:3 and 8:2 were used in all examples.

[0008] The now-expired EP 0278660B describes clear homogeneous microemulsions containing at least 20% w / w of a hydrophobic phase, at most 20% of a hydrophilic phase, up to 20% of a cationic quaternary ammonium surfactant, and a wide range of compounds suitable as co-surfactants. The hydrophilic phase may contain a significant amount of alcohol.

[0009] WO2013095994A discloses the use of short chain monoalkyl glycerol ethers (substituted or unsubstituted C3-C5 alkyl chains), reported as a new class of green sorbosurfactants by Queste et al. Green Chem., 2006, 8, 822-830, as replacements for 1,2-hexanediol or 1,2-heptanediol, in various microemulsion formulations as disclosed in WO2005123028A1.

[0010] Although the basic understanding of microemulsions seems to suggest microemulsions as a formulation for aqueous-based fragrances, it is also recognized that oil-in-water emulsions typically incorporate significant amounts of surfactants compared to the oil phase. The need for such large amounts of surfactants in oil-in-water emulsions significantly limits the percentage of fragrance that can be added to the mixture. Furthermore, many surfactants mask, alter, or otherwise affect the olfactory response to fragrance ingredients, thus making dispersed microemulsions unsuitable as non-ethanol fragrance delivery systems. Furthermore, microbial growth tends to be a problem, even with the addition of typical preservatives.

[0011] Thus, there is a need to develop a clear aqueous fragrance composition that overcomes one or more of the drawbacks of conventional approaches, such as providing an efficient, optically clear, non-greasy, non-sticky fragrance microemulsion without altering or compromising the fragrance overtones, and that is resistant to microbial growth. Summary of the Invention

[0012] The present invention generally relates to aqueous fragrance compositions.The present invention is premised on the fact that clear aqueous fragrance microemulsion compositions can be created by using monoalkyl glycerol ethers with longer alkyl or alkylene chains in the absence of ethanol or other short chain alcohols or diols.

[0013] According to an embodiment of the present invention there is provided a clear aqueous fragrance microemulsion composition comprising (or consisting essentially of, or consisting of): (a) a fragrance material, the fragrance material being present in an amount in the range of 3 wt% to 65 wt%; (b) a sorbosurfactant comprising, consisting essentially of, or consisting of a monoalkyl glycerol ether having the formula (I): RO-CH2-CH(OH)-CH2OH, where R is selected from the group consisting of C8-C12 unbranched alkyl and C6-C7 unbranched terminal alkenyl, the sorbosurfactant being present in an amount in the range of 0.1 wt% to 25 wt%; (c) an ionic surfactant present in an amount ranging from 0.5 wt % to 20 wt %; (d) a nonionic surfactant present in an amount ranging from 0 wt % to 20 wt %; (e) a quantity (qs) of water; Including, Here, each wt % is based on the total weight of the microemulsion composition.

[0014] The present invention also relates to the use of a sorbosurfactant (b) as defined above for preparing a clear aqueous perfume microemulsion composition.

[0015] The objects and advantages of the present invention will be further understood in light of the following detailed description and examples. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0016] The present invention is premised on the recognition that in the absence of ethanol, clear, aqueous fragrance microemulsion compositions are surprisingly produced using monoalkyl glycerol ethers having longer (C8-C12) unbranched alkyl or (C6-C7) unbranched alkylene chains.

[0017] "Substantially free of ethanol", in the context of the present invention, means that less than 1 weight percent (wt%) (wt%), preferably less than 0.1 wt%, and more preferably no ethanol is intentionally added to the material ("ethanol-free").

[0018] As used herein, "monoalkyl glycerol ether" or "MAGE" refers to a glycerol-based compound that has only one unbranched alkyl or unbranched alkylene group on one of the primary hydroxyl groups of glycerol (1,2,3-trihydroxypropane), with the remaining two hydroxyl groups being unsubstituted. As used herein, MAGE compounds are "sorbosurfactants" useful for forming clear aqueous fragrance microemulsion compositions.

[0019] The term "microemulsion" as used herein means a pseudo one-phase transparent mixture of (i) two immiscible fluids and (ii) at least one monoalkyl glycerol ether sorbosurfactant. Microemulsions are isotropic solutions that can solubilize both water and oil, are thermodynamically stable, and typically form spontaneously. They are stable due to the presence of an interfacial membrane that contains surface-active molecules. Microemulsions are transparent and do not exhibit the turbidity (milky white color) of standard emulsions. There are several types of microemulsions, which depend mainly on the rigidity of the amphiphilic monolayer that separates the oily and aqueous microdomains. There are three types of microemulsions: oil-swollen micelles, water-swollen reverse micelles, and bicontinuous structures. The particle size of the resulting micelles or structures is small enough that the resulting mixture is optically transparent.

[0020] For the purposes of the present invention, the term "optically clear" is used to define a composition that is "transparent" (i.e., transmits light without distortion), meaning that the size of the emulsion particles in the composition is reduced to a size where the particles are not observable by optical (viewing) means. The turbidity / clarity of the microemulsion compositions was measured at room temperature on samples taken at various time intervals and aging temperatures: a) 1.5 hours at room temperature, b) 24 hours at 5°C and 50°C, c) 1 week at 5°C and 50°C, and d) 2 weeks at 5°C and 50°C. Turbidity measurements were made at room temperature using a calibrated AQUALYTIC® TurbiDirect turbidimeter (following the manufacturer's instructions and standards) and averaged from three consecutive measurements on the same sample, reported in nephelometric turbidity units (NTU). As used herein, an optically clear (transparent) aqueous fragrance microemulsion composition has a room temperature turbidity value of 12 NTU or less. Preferably, the optically clear perfume microemulsions of the present invention have turbidity values ​​of 12 NTU or less after aging for two weeks at 5°C and 50°C.

[0021] According to an embodiment of the present invention, the substantially ethanol-free aqueous fragrance microemulsion composition comprises the following components: (a) a fragrance material; (b) a sorbosurfactant; (c) an ionic surfactant; (d) an optional nonionic surfactant; and (e) water. The aqueous fragrance microemulsion composition may also optionally contain one or more additional components, such as antioxidants, chelating agents, UV filters, preservatives, thickeners, cosmetic actives, moisturizers, humectants, emollients, opacifiers, pearly gloss impacting substances, pigments, colorants, dyes, and defoamers.

[0022] The aqueous fragrance microemulsion compositions of the present invention comprise one or more sorbosurfactants, which comprise, consist essentially of, or consist of monoalkyl glycerol ethers having the formula (I): RO-CH2-CH(OH)-CH2OH, where R is selected from the group consisting of C8-C12 unbranched alkyl and C6-C7 unbranched terminal alkenyl (i.e., C6-C7 alkenyl with a carbon-carbon double bond at the end of the carbon chain). In one embodiment, R is selected from C8-C12 unbranched alkyl, such as n-octyl, n-nonyl, n-decyl, or n-undecyl. In another embodiment, R is selected from C6-C7 unbranched terminal alkenyl, such as hex-5-enyl or hept-6-enyl. Preferably, the monoalkyl glycerol ether sorbosurfactant is selected from the group consisting of 1-octyl glycerol ether, 1-nonyl glycerol ether, 1-decyl glycerol ether, 1-undecyl glycerol ether, 1-hex-5-enyl glycerol ether, 1-hept-6-enyl glycerol ether, and combinations thereof. More preferably, the monoalkyl glycerol ether sorbosurfactant is selected from the group consisting of 1-octyl glycerol ether, 1-decyl glycerol ether, and combinations thereof.

[0023] Other types of sorbosurfactants disclosed in the prior art, such as 1,2-hexanediol or 1-pentylglycerol ether, are highly soluble in water. However, sorbosurfactants within the scope of formula (I) have relatively low water solubility, yet are surprisingly efficient in forming stable, clear, aqueous perfume microemulsion compositions.

[0024] The amount of sorbosurfactant present in the aqueous fragrance microemulsion composition generally ranges from about 0.1 wt % to about 25 wt %, preferably from about 0.1 wt % to about 20 wt %, more preferably from about 0.5 wt % to about 20 wt %, and most preferably from about 0.5 wt % to about 15 wt %, based on the total weight of the aqueous fragrance microemulsion composition.

[0025] Monoalkyl glycerol ethers can be synthesized using standard organic chemistry techniques such as reacting glycidol with a suitable alcohol under basic conditions. For example, 1-octyl glycerol ether can be synthesized by reacting 1-octanol and glycidol in the presence of a catalytic amount of sodium hydroxide. Alternatively, monoalkyl glycerol ethers can be synthesized by alkylating solketal (2,2-dimethyl-4-((octyloxy)methyl)-1,3-dioxolane) with the appropriate alkyl or alkenyl halide, followed by hydrolysis of the acetonide protecting group. For example, 1-octyl glycerol ether can be synthesized by reacting 1-bromooctane with the anion of solketal, followed by acidic hydrolysis of the acetonide protecting group.

[0026] The aqueous fragrance microemulsion compositions of the present invention further comprise ionic surfactants, such as anionic, cationic, amphoteric, and mixtures thereof, and may further comprise nonionic surfactants. Preferred surfactant combinations include mixtures of anionic and nonionic surfactants, mixtures of cationic and nonionic surfactants, and mixtures of zwitterionic and nonionic surfactants.

[0027] Suitable anionic surfactants can include any conventional anionic surfactant, including, for example, sulfate detergent surfactants for alkoxylated and / or non-alkoxylated alkyl sulfate materials, and / or sulfonate detergent surfactants, such as alkylbenzene sulfonates. The anionic surfactants can be linear, branched, or a combination thereof. Non-limiting examples of anionic surfactants include C11-C18 alkylbenzene sulfonates; primary or branched C10-C20 alkyl sulfates; unsaturated sulfates such as oleyl sulfate; C10-C18 alkyl alkoxy sulfates, especially those containing 1-7 ethoxy groups; C10-C18 alkyl alkoxy carboxylates, especially those containing 1-5 ethoxy groups; C10-C18 alkyl polyglycosides and their corresponding sulfated polyglycosides, C12-C18 α-sulfonated fatty acid esters, monoalkyl sulfosuccinates (monoalkyl sulfosuccinates), and dialkyl sulfosuccinates (dialkyl sulfosuccinates). Other anionic surfactants useful herein are the water-soluble salts of alkylphenol ethylene oxide ether sulfates and the water-soluble salts of esters of alpha-sulfonated fatty acids. Fatty acid-based anionic surfactants include saturated and / or unsaturated fatty acids obtained from natural sources or prepared synthetically. Other exemplary anionic surfactants include acyl glycinate salts, such as sodium cocoyl glycinate; acyl hydrolyzed wheat protein salts, such as sodium cocoyl hydrolyzed wheat protein, and cocoamphodiacetate salts, such as disodium cocoamphodiacetate.Other exemplary anionic surfactants include acyl glutamates such as sodium cocoyl glutamate, sodium lauroyl glutamate, sodium caproyl glutamate, sodium myristoyl glutamate, sodium stearoyl glutamate, sodium oleoyl glutamate, sodium palmitoyl glutamate, or sodium linoleoyl glutamate; and other anionic surfactants such as sodium cocoyl sulfate, sodium isethionate, or sodium surfactin. Examples of suitable fatty acids include, but are not limited to, capric acid, lauric acid, myristic acid, palmitic acid, stearic acid, arachidic acid, and behenic acid. Other fatty acids include palmitoleic acid, oleic acid, linoleic acid, linolenic acid, and ricinoleic acid. Examples of monoalkyl sulfosuccinates include, but are not limited to, disodium monooctyl sulfosuccinate, and disodium laureth sulfosuccinate. Examples of suitable dialkyl sulfosuccinate include, but are not limited to, dioctyl sodium sulfosuccinate, dinonyl ammonium sulfosuccinate, diamyl sodium sulfosuccinate, dicapryl sodium sulfosuccinate, diethylhexyl sodium sulfosuccinate, diheptyl sodium sulfosuccinate, dihexyl sodium sulfosuccinate, diisobutyl sodium sulfosuccinate, ditridecyl sodium sulfosuccinate, and combinations thereof. Examples of commercially available dioctyl sodium sulfosuccinate products include AEROSOL® OT-70 PG from Solvay (Brussels, Belgium) or TEGO® sulfosuccinate DO 75 from Evonik Operations GmbH (Essen, Germany).

[0028] Suitable cationic surfactants include quaternary ammonium surfactants such as alkyl trimethyl ammonium halides. Examples of suitable quaternary ammonium surfactants include, but are not limited to, cetrimonium chloride, coconut trimethyl ammonium chloride (chloride) or bromide, coconut methyl dihydroxyethyl ammonium chloride or bromide, decyl triethyl ammonium chloride, decyl dimethyl hydroxyethyl ammonium chloride or bromide, C12-C15 dimethyl hydroxyethyl ammonium chloride or bromide, coconut dimethyl hydroxyethyl ammonium chloride or bromide, myristyl trimethyl ammonium methyl sulfate, lauryl dimethyl benzyl ammonium chloride or bromide, lauryl dimethyl (ethenoxy) 4 ammonium chloride or bromide, and choline esters.

[0029] Suitable zwitterionic surfactants can include any conventional zwitterionic surfactants, including betaines, including alkyl dimethyl betaines and coco dimethyl amidopropyl betaines, C8-C18 (e.g., C12-C14) amine oxides (e.g., C12-C14 dimethyl amine oxide), and / or sulfo and hydroxy betaines (wherein the alkyl group can be C8-C18 or C10-C14), such as N-alkyl-N,N-dimethylamino-1-propanesulfone.

[0030] The ionic surfactant is present in the aqueous fragrance microemulsion composition in an amount ranging from about 0.5 wt % to about 20 wt %, for example, from about 3 wt % to about 19 wt %, and more preferably, from about 5 wt % to about 18 wt %, based on the total weight of the aqueous fragrance microemulsion composition.

[0031] According to one embodiment of the present invention, the aqueous fragrance microemulsion composition of the present invention may further comprise a non-ionic surfactant. Suitable non-ionic surfactants include alkoxylated fatty alcohols, such as ethoxylated fatty alcohols. Other suitable non-ionic surfactants include alkoxylated alkylphenols, alkylphenol condensates, mid-chain branched alcohols, mid-chain branched alkyl alkoxylates, alkyl glucosides, alkyl polysaccharides (e.g., alkyl polyglycosides), polyhydroxy fatty acid amides, ether-capped poly(oxyalkylated) alcohols, polyglyceryl esters, and mixtures thereof. The alkoxylate units may be ethyleneoxy units, propyleneoxy units, or mixtures thereof. The non-ionic surfactants may be linear, branched (e.g., mid-chain branched), or combinations thereof. Particular non-ionic surfactants may include alcohols having an average of about 12 to about 16 carbons and an average of about 3 to about 9 ethoxy groups (e.g., C12-C14 EO7 non-ionic surfactants). Exemplary nonionic surfactants include ethoxylated alkylphenol ethers, especially octyl and nonylphenol ethers containing 5-20 EO; ethoxylated aliphatic C6-C20 alcohols, which may be linear or branched, and Guerbet-type alcohols containing 2-30 EO; ethoxylated sterols containing 5-20 EO; polyethylene glycol (2-10 EO) mono- and diesters of aliphatic C5-C11 carboxylic acids; ethoxylated castor oil or hydrogenated castor oil derivatives containing 10-60 EO, such as PEG-40 hydrogenated castor oil (e.g., CREMOPHOR® RH 40; BASF, Germany). Non-limiting examples of suitable non-ionic surfactants include polyglyceryl-4-caprate, decyl glucoside or polyglucoside, lauryl glucoside or polyglucoside, coco glucoside or polyglucoside, or PEG-40 hydrogenated castor oil.

[0032] The amount of (optional) non-ionic surfactant present in the aqueous perfume microemulsion composition is generally present in an amount ranging from 0 wt% to about 20 wt%. If a non-ionic surfactant is present in the composition, the amount of surfactant is preferably from about 0.5 wt% to about 20 wt%, and more preferably from about 2 wt% to about 15 wt%, based on the total weight of the aqueous perfume microemulsion composition.

[0033] Examples of preferred surfactant systems include combinations of anionic and nonionic surfactants. Examples of particularly preferred surfactants include combinations of anionic and nonionic surfactants, such as a combination of dialkyl sulfosuccinate and ethoxylated hydrogenated castor oil. In one embodiment, the surfactant used in combination with the monoalkyl glycerol ether sorbosurfactant includes a mixture of dioctyl sodium sulfosuccinate and PEG-40 hydrogenated castor oil.

[0034] The total amount of surfactants (ionic and nonionic) that may be used in the compositions of the present invention generally ranges from about 0.5 wt % to about 45 wt %, preferably from about 5 wt % to about 40 wt %, more preferably from 10 to about 30 wt %, and most preferably from about 15 to about 25 wt %, based on the total weight of the aqueous fragrance microemulsion composition.

[0035] According to one embodiment of the invention, the mass ratio between the mass of the fragrance substance and the (total) mass of the sorbosurfactant / surfactant mixture is generally between 1:1 and 10:1, preferably between 1:1 and 6:1, more preferably between 1:1 and 5:1, and most preferably between 1:1 and 4:1.

[0036] In a further embodiment, the sorbo-surfactant within the scope of formula (I) can be used in combination with other known sorbo-surfactants outside the scope of formula (I). For example, the present sorbo-surfactant within the scope of formula (I) can be used in combination with 1,2-alkanediols such as 1,2-pentanediol, 1,2-hexanediol, 1,2-octanediol, or mixtures thereof; butylene glycol; short chain (C1-C5) monoalkyl glycerol ethers such as 1-butyl glycerol ether; isosorbide derivatives such as endo- and exo-forms of propyl isosorbide, butyl isosorbide, pentyl isosorbide, or dimethyl isosorbide; diisopropylidene glycerol (solketal or Augeo® crystals), or mixtures thereof; or mixtures of two or more of the foregoing. When using such combinations, the mass ratio between the sorbo-surfactant of formula (I) and the alternative known sorbo-surfactant can be 100:1 to 1:1, preferably 10:1 to 1:1. In another embodiment, the aqueous perfume microemulsion may be void of any 1,2-alkanediol, short chain (C1-C5) monoalkyl glycerol ether, and / or isosorbide derivative.

[0037] The aqueous perfume microemulsion compositions of the present invention comprise one or more perfume materials (a), such as natural and / or synthetic perfume raw materials. Of particular interest are oil-soluble perfume oils, which may or may not be in admixture with water-soluble perfume oils, and individual perfume compounds. Oil-soluble perfume oils are natural or essential oils, concretes, absolutes, resins, resinoids, balsams and tinctures such as ambergris tincture; amyris oil; angelica seed oil; angelica root oil; anise oil; valerian oil; basil oil; wood moss absolute; laurel oil; almoise oil; benzoin resin; bergamot oil; beeswax absolute; birch tar oil; bitter almond oil; savory oil; buchu leaf oil; cabreuva oil; juniper oil; iris decoction; camphor oil; cananga oil; cardamom oil; cascarilla oil; cassia oil; cassie absolute; castoreum absolute; cedarwood oil; cedarwood oil; cistus oil. oil);citronella oil;lemon oil;copaiba balsam;copaiba balsam oil;coriander oil;costus root oil;cumin oil;cypress oil;davana oil;dill weed oil;dill seed oil;eau de brouts absolute;oakmoss absolute;elemi oil;tarragon oil;eucalyptus citriodora citriodora oil;eucalyptus oil;fennel oil;fir needle oil;galbanum oil;galbanum resin;geranium oil;grapefruit oil;gruyun oil;gruyun balsam;gruyun balsam oil;helichrysum absolute;helichrysum oil;ginger oil;iris root absolute;iris root oil;jasmine absolute;calamus oil;blue chamomile oil;roman chamomile oil;carrot seed oil;cascarilla oil;pine needle oil;spearmint oil;caraway oil;labdanum oil;labdanum absolute;labdanum resin;lavandin absolute;lavandin oil;lavender absolute;lavender oil;lemongrass oil;lovage oil;distilled lime oil;expressed lime oil;linaloe oil;Litsea cubeba oil;bay leaf oil;mace oil;marjoram oil;mandarin oil;massoi bark oil;mimosa absolute;ambrette seed oil;mus tinkling;clary sage oil;nutmeg oil;myrrh absolute;myrrh oil;periwinkle oil;clove leaf oil;clove bud oil;neroli oil;olibanum absolute;olibanum oil;opopanax oil;orange flower absolute;orange oil;oregano oil;palmarosa oil;patchouli oil;perilla oil;pew balsam balsam oil;parsley leaf oil;parsley seed oil;petitgrain oil;mint oil;pepper oil;pimento oil;pine oil;pennyroyal oil;rose absolute;rosewood oil;rose oil;rosemary oil;dalmatian sage oil;spanish sage oil;sandalwood oil;celery seed oil;spike lavender oil;star anise oil;styrax oil;tagetes oil;fir needle oil;tea tree oil;turpentine;thyme oil;tolu balsam;tonka bean absolute;tuberose absolute;vanilla extract;violet leaf absolute;verbena oil;vetiver oil;juniper berry The essential oil may be a natural-identical essential oil selected from the group consisting of extracts of natural sources, such as berry oil; sake lees oil; mugwort oil; wintergreen oil; ylang-ylang oil; hyssop oil; civet absolute; cinnamon leaf oil; cinnamon bark oil, and fractions thereof or components isolated therefrom;

[0038] Further, the one or more aromatic substances may be selected from the group consisting of: aliphatic aldehydes and their acetals; aliphatic ketones and their oximes; aliphatic sulfur-containing compounds; aliphatic nitriles; esters of aliphatic carboxylic acids; formates, acetates, propionates, isobutyrates, butyrates, isovalerates, pentanoates, hexanoates, crotonates, tiglates, or 3-methyl-2-butenoates of acyclic or cyclic (cyclic) terpene alcohols; acyclic terpene aldehydes and ketones; cyclic terpenes. The odorants may be selected from individual odorants from: aldehydes and ketones; cyclic and alicyclic ethers; cyclic and macrocyclic ketones; alicyclic aldehydes and ketones, esters of cyclic and alicyclic alcohols; esters of alicyclic carboxylic acids, esters of araliphatic alcohols and aliphatic carboxylic acids; araliphatic ethers; aromatic and araliphatic aldehydes; aromatic and araliphatic ketones; aromatic and araliphatic carboxylic acids and esters; nitrogen-containing aromatic compounds; phenyl ethers and phenyl esters; heterocyclic compounds; and combinations thereof.

[0039] Exemplary hydrocarbons include, but are not limited to, 3-carene, alpha-pinene, β-pinene, alpha-terpinene, gamma-terpinene, p-cymene, bisabolene, camphene, caryophyllene, cedrene, farnesene, limonene, longifolene, myrcene, ocimene, valencene, (E,Z)-1,3,5-undecatriene, styrene, and diphenylmethane.

[0040] Representative aliphatic aldehydes and their acetals include, but are not limited to, hexanal, heptanal, octanal, nonanal, decanal, undecanal, dodecanal, tridecanal, 2-methyloctanal, 2-methylnonanal, (E)-2-hexenal, (Z)-4-heptenal, 2,6-dimethyl-5-heptenal, 10-undecenal, (E)-4-decenal, 2-dodecenal, 2,6,10-trimethyl-9-undecenal, 2,6,10-trimethyl-5,9-undecadienal, heptanal diethyl acetal, 1,1-dimethoxy-2,2,5-trimethyl-4-hexene, citronellyloxyacetaldehyde, and 1-(1-methoxypropoxy)-(E / Z)-3-hexene.

[0041] Exemplary aliphatic ketones and their oximes include, but are not limited to, 2-heptanone, 2-octanone, 3-octanone, 2-nonane, 5-methyl-3-heptanone, 5-methyl-3-heptanone oxime, 2,4,4,7-tetramethyl-6-octen-3-one, and 6-methyl-5-hepten-2-one.

[0042] Exemplary aliphatic sulfur-containing compounds include, but are not limited to, 3-methylthiohexanol, 3-methylthiohexyl acetate, 3-mercaptohexanol, 3-mercaptohexyl acetate, 3-mercaptohexyl butyrate, 3-acetylthiohexyl acetate, and 1-menthene-8-thiol.

[0043] Exemplary aliphatic nitriles include, but are not limited to, 2-nonenoic acid nitrile, 2-undecenoic acid nitrile, 2-tridecenoic acid nitrile, 3,12-tridecadienoic acid nitrile, 3,7-dimethyl-2,6-octadienoic acid nitrile, and 3,7-dimethyl-6-octenoic acid nitrile.

[0044] Exemplary esters of aliphatic carboxylic acids include (E)- and (Z)-3-hexenyl formate, ethyl acetoacetate, isoamyl acetate, hexyl acetate, 3,5,5-trimethylhexyl acetate, 3-methyl-2-butenyl acetate, (E)-2-hexenyl acetate, (E)- and (Z)-3-hexenyl acetate, octyl acetate, 3-octyl acetate, 1-octen-3-yl acetate, ethyl butyrate, butyl butyrate, isoamyl butyrate, hexyl butyrate, (E)- and (Z)-3-hexenyl isobutyrate, hexyl crotonate, and the like. Examples of ethyl 2-methyl-3,4-dihydro-1,1-dihydro-2,1-dihydro-1,1-dihydro-2,1-dihydro-1,1-dihydro-2,1-dihydro-1,1-dihydro-2,1-dihydro-1,1-dihydro-2,1-dihydro-1,1-dihydro-2,1-dihydro-1,1-dihydro-2,1-dihydro-1,1-dihydro-2,1-dihydro-1,1-dihydro-2,1-dihydro-1,1-dihydro-2,1-dihydro-1,1-dihydro-2,1-dihydro-1,1-dihydro-2,1-dihydro-1,1-dihydro-2,1-dihydro-1

[0045] Exemplary formate, acetate, propionate, isobutyrate, butyrate, isovalerate, pentanoate, hexanoate, crotonate, tiglate or 3-methyl-2-butenoate acyclic and cyclic terpene alcohols include citronellol, geraniol, nerol, linalool, lavandulol, nerolidol, farnesol, tetrahydrolinalool, tetrahydrogeraniol, 2,6-dimethyl-7-octen-2-ol, 2,6-dimethyloctan-2-ol, 2-methyl-6-methylene-7-octen-2-ol, 2,6-dimethyl-5,7-octadien-2-ol, 2,6-dimethyl-3,5-octadien-2-ol, 2,6-dimethyl-4,4-diene-2-ol, 2,6-dimethyl-5,7-octadien-2-ol, 2,6-dimethyl-6,4-diene-2-ol, 2,6-dimethyl-5,7-octadien-2-ol, 2,6-dimethyl-3,5-octadien-2-ol, 2,6-dimethyl-5,7 ... 2-ol, 3,7-dimethyl-4,6-octadien-3-ol, 3,7-dimethyl-1,5,7-octatrien-3-ol, and 2,6-dimethyl-2,5,7-octatrien-1-ol, as well as esters derived from cyclic terpene alcohols, such as, but not limited to, menthol, isopulegol, α-terpineol, terpinenol-4, menthan-8-ol, menthan-1-ol, menthan-7-ol, borneol, isoborneol, linalool oxide, nopol, cedrol, ambrinol, vetiverol, and guaiol.

[0046] Exemplary acyclic terpene aldehydes and ketones include, but are not limited to, geranial, neral, citronellal, 7-hydroxy-3,7-dimethyloctanal, 7-methoxy-3,7-dimethyloctanal, 2,6,10-trimethyl-9-undecenal, geranyl acetone, and their dimethyl and diethyl acetals, such as the dimethyl and diethyl acetals of geranial, neral, and 7-hydroxy-3,7 dimethyloctanal.

[0047] Exemplary cyclic terpene aldehydes and ketones include menthone, isomenthone, 8-mercaptomenthan-3-one, carvone, camphor, phenthone, α-ionone, β-ionone, α-n-methylionone, β-n-methylionone, α-isomethylionone, β-isomethylionone, α-iron, alpha damascone, beta damascone, beta damascenone, delta damascone, gamma damascone, 1-(2,4,4-trimethyl-2-cyclohexene-1-yl)-1,2-dimethyl-2,3-dimethyl ... Examples of the acetylated methyl ketone include, but are not limited to, 1,3,4,6,7,8a-hexahydro-1,1,5,5-tetramethyl-2H-2,4a-methanonaphthalen-8(5H)-one, 2-methyl-4-(2,6,6-trimethyl-1-cyclohexen-1-yl)-2-butenal, nootkatone, dihydronootkatone, 4,6,8-megastigmatrien-3-one, alpha-sinensal, beta-sinensal, and acetylated cedar wood oil (methyl cedryl ketone).

[0048] Exemplary cyclic and cyclic aliphatic ethers include, but are not limited to, cineole, cedryl methyl ether, cyclododecyl methyl ether, 1,1 dimethoxycyclododecane, (ethoxymethoxy)cyclododecane, alpha-cedrene epoxide, 3a,6,6,9a-tetramethyldodecahydronaphtho[2,1-b]furan, 3a-ethyl-6,6,9a-trimethyldodecahydronaphtho[2,1-b]furan, 1,5,9-trimethyl-13-oxabicyclo[10.1.0]trideca-4,8-diene, rose oxide, and 2-(2,4-dimethyl-3-cyclohexen-1-yl)-5-methyl-5-(1-methylpropyl)-1,3-dioxane.

[0049] Exemplary cyclic and macrocyclic ketones include 4-tert-butylcyclohexanone, 2,2,5-trimethyl-5-pentylcyclopentanone, 2-heptylcyclopentanone, 2-pentylcyclopentanone, 2-hydroxy-3-methyl-2-cyclopenten-1-one, 3-methyl-cis-2-penten-1-yl-2-cyclopenten-1-one, 3-methyl-2-pentyl-2-cyclopenten-1-one, 3-methyl-4-cyclopentadecenone, 3-methyl-5-cyclopentadecenone, 3-methyl ... These include, but are not limited to, pentadecanone, 4-(1-ethoxyvinyl)-3,3,5,5-tetramethylcyclohexanone, 4-tert-pentylcyclohexanone, 5-cyclohexadecen-1-one, 6,7-dihydro-1,1,2,3,3-pentamethyl-4(5H)-indanone, 8-cyclohexadecen-1-one, 7-cyclohexadecen-1-one, (7 / 8)-cyclohexadecen-1-one, 9-cycloheptadecen-1-one, cyclopentadecanone, and cyclohexadecanone.

[0050] Exemplary cycloaliphatic aldehydes and ketones include 2,4-dimethyl-3-cyclohexenecarbaldehyde, 2-methyl-4-(2,2,6-trimethylcyclohexen-1-yl)-2-butenal, 4-(4-hydroxy-4-methylpentyl)-3-cyclohexenecarbaldehyde, 4-(4-methyl-3-penten-1-yl)-3-cyclohexenecarbaldehyde, 1-(3,3-dimethylcyclohexyl)-4-penten-1-one, 2,2-dimethyl-1-(2,4- These include, but are not limited to, dimethyl-3-cyclohexen-1-yl)-1-propanone, 1-(5,5-dimethyl-1-cyclohexen-1-yl)-4-penten-1-one, 2,3,8,8-tetramethyl-1,2,3,4,5,6,7,8-octahydro-2-naphthalenyl methyl ketone, methyl-2,6,10-trimethyl-2,5,9-cyclododecatrienyl ketone, and tert-butyl-(2,4-dimethyl-3-cyclohexen-1-yl) ketone.

[0051] Exemplary esters of cyclic and cyclic aliphatic alcohols include 2-tert-butylcyclohexyl acetate, 4-tert-butylcyclohexyl acetate, 2-tert-pentylcyclohexyl acetate, 4-tert-pentylcyclohexyl acetate, 3,3,5-trimethylcyclohexyl acetate, decahydro-2-naphthyl acetate, 2-cyclopentylcyclopentyl crotonate, 3-pentyltetrahydro-2H-pyran-4-yl acetate, decahydro-2,5,5,8-tetramethylcyclohex ... Examples of suitable aryl esters include, but are not limited to, a-tetramethyl-2-naphthyl acetate, 4,7-methano-3a,4,5,6,7,7a-hexahydro-5- or 6-indenyl acetate, 4,7-methano-3a,4,5,6,7,7a-hexahydro-5- or 6-indenyl propionate, 4,7-methano-3a,4,5,6,7,7a-hexahydro-5- or 6-indenyl isobutyrate, 4,7-methanooctahydro-5- or 6-indenyl acetate, and 1-cyclohexylethyl crotonate.

[0052] Exemplary esters of alicyclic carboxylic acids include, but are not limited to, allyl-3-cyclohexyl propionate, allylcyclohexyl oxyacetate, cis- and trans-methyl dihydrojasmonate, cis- and trans-methyl jasmonate, methyl-2-hexyl-3-oxocyclopentanecarboxylate, ethyl-2-ethyl-6,6-dimethyl-2-cyclohexenecarboxylate, ethyl-2,3,6,6-tetramethyl-2-cyclohexenecarboxylate, and ethyl-2-methyl-1,3-dioxolane-2-acetate.

[0053] Exemplary esters of araliphatic alcohols and aliphatic carboxylic acids include, but are not limited to, benzyl acetate, benzyl propionate, benzyl isobutyrate, benzyl isovalerate, 2-phenylethyl acetate, 2-phenylethyl propionate, 2-phenylethyl isobutyrate, 2-phenylethyl isovalerate, 1-phenylethyl acetate, α-trichloromethylbenzyl acetate, α,α-dimethylphenylethyl acetate, α,α-dimethylphenylethyl butyrate, cinnamyl acetate, 2-phenoxyethyl isobutyrate, and 4-methoxybenzyl acetate.

[0054] Exemplary aromatic aliphatic ethers include, but are not limited to, 2-phenylethyl methyl ether, 2-phenylethyl isoamyl ether, 2-phenylethyl 1-ethoxyethyl ether, phenylacetaldehyde dimethyl acetal, phenylacetaldehyde diethyl acetal, hydratropaldehyde dimethyl acetal, phenylacetaldehyde glycerol acetal, 2,4,6-trimethyl-4-phenyl-1,3-dioxane, 4,4a,5,9b-tetrahydroindeno[1,2-d]-m-dioxin, and 4,4a,5,9b-tetrahydro-2,4-dimethylindeno[1,2-d]-m-dioxin.

[0055] Exemplary aromatic and araliphatic aldehydes include benzaldehyde, phenylacetaldehyde, 3-phenylpropanal, hydratropaldehyde, 4-methylbenzaldehyde, 4-methylphenylacetaldehyde, 3-(4-ethylphenyl)-2,2-dimethylpropanal, 2-methyl-3-(4-isopropylphenyl)propanal, 2-methyl-3-(4-tert-butylphenyl)propanal, 2-methyl-3-(4-isobutylphenyl)propanal, 3-(4-tert-butylphenyl)propanal, cinnamaldehyde, phenylacet ... Aldehydes include, but are not limited to, α-butylcinnamaldehyde, α-amylcinnamaldehyde, α-hexylcinnamaldehyde, 3-methyl-5-phenylpentanal, 4-methoxybenzaldehyde, 4-hydroxy-3-methoxybenzaldehyde, 4-hydroxy-3-ethoxybenzaldehyde, 3,4-methylenedioxybenzaldehyde, 3,4-dimethoxybenzaldehyde, 2-methyl-3-(4-methoxyphenyl)propanal, and 2-methyl-3-(4-methylenedioxyphenyl)propanal.

[0056] Illustrative aromatic and aromatic aliphatic ketones include acetophenone, 4-methylacetophenone, 4-methoxyacetophenone, 4-tert-butyl-2,6-dimethylacetophenone, 4-phenyl-2-butanone, 4-(4-hydroxyphenyl)-2-butanone, 1-(2-naphthalenyl)ethanone, 2-benzofuranylethanone, (3-methyl-2-benzofuranyl)ethanone, benzophenone, 1,1 , 2,3,3,6-hexamethyl-5-indanyl methyl ketone, 6-tert-butyl-1,1-dimethyl-4-indanyl methyl ketone, 1-[2,3-dihydro-1,1,2,6-tetramethyl-3-(1-methylethyl)-1H-5-indenyl]ethanone, and 5',6',7',8'-tetrahydro-3,5,5,6,8,8-hexamethyl-2-acetonaphthone.

[0057] Exemplary aromatic and araliphatic carboxylic acids and esters thereof include, but are not limited to, benzoic acid, phenylacetic acid, methyl benzoate, ethyl benzoate, hexyl benzoate, benzyl benzoate, methyl phenyl acetate, ethyl phenyl acetate, geranyl phenyl acetate, phenylethyl phenyl acetate, methyl cinnamate, ethyl cinnamate, benzyl cinnamate, phenylethyl cinnamate, cinnamyl cinnamate, allyl phenoxyacetate, methyl salicylate, isoamyl salicylate, hexyl salicylate, cyclohexyl salicylate, cis-3-hexenyl salicylate, benzyl salicylate, phenylethyl salicylate, methyl-2,4-dihydroxy-3,6-dimethylbenzoate, ethyl-3-phenylglycidate, and ethyl-3-methyl-3-phenylglycidate.

[0058] Exemplary nitrogen-containing aromatic compounds include, but are not limited to, 2,4,6-trinitro-1,3-dimethyl-5-tert-butylbenzene, 3,5-dinitro-2,6-dimethyl-4-tert-butylacetophenone, cinnamonitrile, 3-methyl-5-phenyl-2-pentenoic acid nitrile, 3-methyl-5-phenylpentanoic acid nitrile, methyl anthranilate, methyl-N-methyl anthranilate, the Schiff base of 7-hydroxy-3,7-dimethyloctanal and methyl anthranilate, 2-methyl-3-(4-tert-butylphenyl)propanal or 2,4-dimethyl-3-cyclohexenecarbaldehyde, 6-isobutylquinolone, 6-sec-butylquinolone, 2-(3-phenylpropyl)pyridine, indole, skatole, 2-methoxy-3-isopropylpyrazine, and 2-isobutyl-3-methoxypyrazine.

[0059] Exemplary phenyl ethers and phenyl esters include, but are not limited to, estragole, anethole, eugenyl methyl ether, isoeugenyl methyl ether, diphenyl ether, β-naphthyl methyl ether, β-naphthyl ethyl ether, β-naphthyl isobutyl ether, 1,4-dimethoxybenzene, eugenyl acetate, and p-cresyl phenyl acetate.

[0060] Exemplary heterocyclic compounds include 2,5-dimethyl-4-hydroxy-2H-furan-3-one, 2-ethyl-4-hydroxy-5-methyl-2H-furan-3-one, 3-hydroxy-2-methyl-4H-pyran-4-one, 2-ethyl-3-hydroxy-4H-pyran-4-one, and lactones such as 1,4-octanolide, 3-methyl-1,4-octanolide, 1,4-nonanolide, 1,4-decanolide, 8-decen-1,4-olide, 1,4-undecanolide, 1,4-dodecanolide, 1,8-decanolide, 1,5-dodecanolide, 4-methyl-1,4-decanolide, 1,15-pentadecanolide, cis- and trans-1,4-dihydro-1,4-dihydro-1,4-dihydro-1,4-dihydro-1,4-dihydro-1,4-dihydro-1,4-dihydro-1,4-dihydro-1,4-dihydro-1 These include, but are not limited to, 1-pentadecen-1,15-olide, cis- and trans-12-pentadecen-1,15-olide, 1,16-hexadecanolide, 9-hexadecen-1,16-olide, 10-oxa-1,16-hexadecanolide, 11-oxa-1,16-hexadecanolide, 12-oxa-1,16-hexadecanolide, ethylene-1,12-dodecanedioate, ethylene-1,13-tridecanedioate, coumarin, 2,3-dihydrocoumarin, and octahydrocoumarin. Further examples of odorants are known from literature such as "Perfume and Flavor Chemicals", edited by S. Arctander, 1969, Montclair NJ (USA).

[0061] The aqueous perfume microemulsion composition advantageously comprises about 65 weight percent (wt%) or less of perfume material. For example, the aqueous perfume microemulsion composition may comprise from 1 wt% to about 65 wt%, preferably from about 2 wt% to about 50 wt%, and most preferably from about 3 wt% to about 40 wt% of such perfume material, based on the total weight of the aqueous perfume microemulsion composition.

[0062] The aqueous perfume microemulsion composition further comprises a quantity (quantum satis) (qs) of water and may further comprise one or more optional ingredients. In accordance with one embodiment of the present invention, the water may be process water or purified water (e.g., permeated, deionized, or distilled). The amount of water in the composition is generally about 5 wt% to about 95 wt%, preferably about 10 wt% to about 90 wt%, and more preferably about 20 wt% to about 85 wt%, based on the total weight of the aqueous perfume microemulsion composition.

[0063] Additional optional ingredients such as antifoaming agents, antioxidants, chelating agents, UV filters, buffers, preservatives, thickeners, cosmetic actives, moisturizers, humectants, emollients, opacifiers, pearlescent impact materials, pigments, colorants, dyes, and / or defoamers may also be present in the aqueous fragrance microemulsion compositions of the present invention. For example, in one embodiment, an antifoaming agent such as dimethylpolysiloxane may be present to minimize foaming during the microemulsion formation process. In another embodiment, carbonate and / or bicarbonate may be combined with water to provide an aqueous carbonate buffer. In yet another aspect, the carbonate or bicarbonate may be present in an amount sufficient to provide an aqueous buffer having a pH in the range of 4.5 to 8. Optional additional ingredients are generally present in the compositions of the present invention at about 0 wt% to about 5 wt%, preferably about 0.1 wt% to about 3 wt%, and more preferably about 0.2 wt% to about 1 wt%, based on the total weight of the aqueous fragrance microemulsion composition.

[0064] Advantageously, the monoalkyl glycerol ether sorbosurfactant of formula (I) also has antibacterial activity.According to another embodiment, the clear aqueous perfume microemulsion composition may therefore not contain additional preservatives, such as, for example, phenoxyethanol.In yet another embodiment, the clear aqueous perfume microemulsion composition does not contain any antioxidants.

[0065] The clear aqueous fragrance microemulsion compositions according to the present invention can be prepared, for example, by stirring by hand or by simply mixing with a mechanical mixer, the desired components, and any optional components to form a homogeneous mixture. The components of the present invention can be added together to a suitable reaction vessel and mixed in any order using conventional processes known to those skilled in the art. The microemulsions can be made at room temperature or at elevated temperatures, for example, below 90°C, preferably below 55°C, and more preferably near room temperature (e.g., 21-25°C).

[0066] The aqueous fragrance microemulsion compositions of the present invention containing monoalkyl glycerol ether sorbosurfactants are uniquely useful. The monoalkyl glycerol ether sorbosurfactants have low odor and can be formulated as stable, clear, aqueous fragrance compositions with high fragrance loadings in several different product forms. The monoalkyl glycerol ethers are very low odor, so the olfactory profile of the fragrance is not altered. This allows the fragrance to retain the desired odor profile of the fully formulated fragrance. The aqueous fragrance microemulsion compositions containing monoalkyl glycerol ether sorbosurfactants use relatively small amounts of surfactant, and as such are comfortable to use, feeling like a smooth emollient without the oiliness or stickiness of most currently known fragrance microemulsions.

[0067] The aqueous fragrance microemulsion compositions are optically clear, stable at about 5°C to about 50°C, and can be formulated to contain a wide variety of fragrance loadings, for example, about 1 wt% to about 65 wt% fragrance, preferably about 2 wt% to about 50 wt%, and most preferably about 3 wt% to about 40 wt% of such fragrance materials. Advantageously, higher fragrance content microemulsions can be prepared and subsequently diluted with water to the desired concentration relevant to their end use, such as air fresheners (fragrances), eau de toilettes, aqueous fragrances, body sprays, body deodorants, bath products, and products such as refreshing and cleaning wet wipes, aqueous cosmetic compositions, household cleaners, fabric fresheners (e.g., scent boosters, fabric softeners, etc.), air fresheners, and sprayable formulations. Many of these uses require different fragrance loadings, all of which can be readily obtained using the present invention. A single properly formulated perfume microemulsion containing a monoalkyl glycerol ether can be diluted with water, for example, from about 5 wt% water to about 90 wt% water, without losing stability, i.e., the resulting product remains as a microemulsion.Furthermore, aqueous perfume microemulsion compositions containing the monoalkyl glycerol ether of formula (I) can be prepared stably despite the addition of other ingredients such as dyes, gelling agents, iridescent materials, and sparkling materials.

[0068] The following examples are given to illustrate the present invention.These examples are presented for illustrative purposes only, and the present invention embodied herein should not be limited thereto.Unless otherwise stated, all parts and percentages are by weight.

[0069] Working Example: Synthesis of monoalkyl glycerol ethers: The sorbosurfactants were synthesized according to a general procedure of alkylation of solketal ((2,2-dimethyl-1,3-dioxolan-4-yl)methanol, CAS number 100-79-8) with a 1-bromoalkane or 1-bromoalkene, followed by acidic removal of the acetonide protecting group. More specifically, 1 equivalent of solketal and 1.1 equivalents of 1-bromoalkane (or 1-bromoalkene) were dissolved in toluene (to provide about 4M solketal), mixed with 1.5 equivalents of potassium hydroxide and 0.05 equivalents of tetrabutylammonium bromide, and heated to 80° C. for about 2 hours. Once analysis showed substantial conversion of solketal, the reaction mixture was removed from the heat, diluted with water, and the organic phase was separated and washed with water. The organic phase was concentrated and used in the next step without further purification. Removal of the acetonide protecting group can be accomplished by treating the crude reaction product with concentrated hydrochloric acid (about 32%) and water and heating to 40° C. After cooling the reaction mixture to room temperature, the crude monoalkyl glycerol ether can be isolated from the reaction mixture by extraction with methyl tert-butyl ether (MTBE). The MTBE phase can be washed with saturated NaHCO3, then saturated NaCl solution, and then concentrated under reduced pressure to obtain the crude reaction mixture containing the monoalkyl glycerol ether. The purified monoalkyl glycerol ether can be isolated from the crude reaction mixture using standard techniques (e.g., crystallization or distillation).

[0070] [Table 1]

[0071] A clear aqueous fragrance microemulsion composition was formed by mixing the desired amounts of fragrance 1 (Table 2 below), sorbosurfactant, surfactants, and additives in distilled water at room temperature. The turbidity / clarity of the microemulsion composition was measured at room temperature for samples taken at various time intervals and aging temperatures: a) 1.5 hours at room temperature, b) 24 hours at 5°C and 50°C, c) 1 week at 5°C and 50°C, and d) 2 weeks at 5°C and 50°C. Turbidity measurements were performed at room temperature using a calibrated turbidimeter (following the manufacturer's instructions and standards) AQUALYTIC® TurbiDirect, and averaged three measurements taken consecutively at room temperature with the same sample.

[0072] [Table 2]

[0073] [Table 3-1] [Table 3-2]

[0074] To prepare inventive Examples 1, 3, and 5-19, the ingredients listed in Tables 2, 3, or 4 (fragrance, sorbosurfactants 1A-1G, surfactants) are mixed with distilled water until a clear microemulsion is formed. The inventive examples remained stable for 2 weeks at 5° C. and 50° C. Examples 2 and 4 were prepared by diluting aliquots of Examples 1 and 3, respectively (26.8%), with distilled water (73.2%) to obtain clear microemulsions that also remained stable for 2 weeks at 5° C. and 50° C.

[0075] [Table 4]

[0076] To evaluate the efficiency, Comparative Examples C-1 to C-4 were prepared by substituting 1,2-hexanediol, 1-butyl glycerol ether, 1-pentyl glycerol ether, and 1-hexyl glycerol ether, respectively, in the sorbosurfactants of the present invention. The ingredients listed in Table 4 were mixed with distilled water until a clear microemulsion was formed. Turbidity measurements of samples aged for 2 weeks at 5° C. and 50° C. confirmed that the sorbosurfactants of the present invention produce stable, clear, aqueous fragrance microemulsion compositions with similar efficiency as prior art compounds, despite their significantly lower water solubility.

[0077] Unless otherwise explained, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs. In case of conflict, the present specification, including explanations of terms, controls. The singular terms "a," "an," and "the" include plural references unless the context clearly indicates otherwise. Similarly, the word "or" is intended to include "and" unless the context clearly indicates otherwise. The term "comprising" means "including," and thus "comprising A or B" means including A or B, as well as including A and B.

[0078] The present invention has been described by way of a description of one or more embodiments thereof, and although the embodiments have been described in considerable detail, it is not intended to limit the scope of the appended claims to such details. Additional advantages and improvements will readily occur to those skilled in the art. The invention in its broader aspects is therefore not limited to the specific details, representative products and / or methods, and examples shown and described. The various features of the exemplary embodiments described herein may be used in any combination. Thus, departures may be made from such details without departing from the scope of the general inventive concept.

Claims

1. A transparent aqueous flavor microemulsion composition comprising: (a) an aroma substance present in an amount in the range of 3 wt% to 65 wt%; (b) The sorbo surfactant comprising a monoalkyl glycerol ether having the formula (I): R-O-CH 2 -CH(OH)-CH 2 OH, wherein the sorbo surfactant is present in an amount in the range of 0.1 wt% to 25 wt%, and (c) an ionic surfactant present in an amount in the range of 0.5 wt% to 20 wt%; (d) a nonionic surfactant present in an amount in the range of 0 wt% to 20 wt%; (e) an appropriate amount (q.s.) of water; wherein wt% is based on the total weight of the microemulsion composition, and the composition is substantially ethanol-free, aqueous flavor microemulsion composition.

2. The aqueous flavor microemulsion composition according to claim 1, wherein the mass ratio of the mass of the aroma substance to the total mass of the sorbo surfactant, the ionic surfactant and the nonionic surfactant is greater than 1.

3. The aqueous flavor microemulsion composition according to claim 1, wherein R in the monoalkyl glycerol ether of formula (I) is selected from unbranched alkyls of C8 - C12.

4. The aqueous flavor microemulsion composition according to claim 1, wherein R in the monoalkyl glycerol ether of formula (I) is n-octyl or n-decyl.

5. The aqueous flavor microemulsion composition according to claim 1, wherein R in the monoalkyl glycerol ether of formula (I) is selected from unbranched terminal alkenyls of C6 - C7.

6. The aqueous flavor microemulsion composition according to claim 1, wherein the ionic surfactant is selected from the group consisting of anionic surfactants, cationic surfactants, zwitterionic surfactants, and combinations thereof.

7. The aqueous flavor microemulsion composition according to claim 1, wherein the ionic surfactant comprises an anionic surfactant.

8. The aqueous flavor microemulsion composition according to claim 1, wherein the ionic surfactant comprises a dialkyl sulfosuccinate, preferably dioctyl sulfosuccinate.

9. The aqueous flavor microemulsion composition according to claim 1, wherein the ionic surfactant comprises a cationic surfactant.

10. The aqueous flavor microemulsion composition according to claim 1, wherein the ionic surfactant comprises a quaternary ammonium surfactant, preferably cetrimonium chloride.

11. The aqueous flavor microemulsion composition according to claim 1, wherein the nonionic surfactant is selected from the group consisting of polyethoxylated hydrogenated castor oil.

12. The aqueous flavor microemulsion composition according to claim 1, wherein the nonionic surfactant contains PEG-40 hydrogenated castor oil.

13. The ionic surfactant contains dioctyl sulfosuccinate, The aqueous flavor microemulsion composition according to claim 1, wherein the nonionic surfactant contains PEG-40 hydrogenated castor oil.

14. The aqueous flavor microemulsion composition according to claim 1, further comprising a carbonate-based buffer for providing a pH in the range of 4.5 to 8.

15. An amount of defoaming agent sufficient to minimize foaming, and / or 1,2-hexanediol, The aqueous flavor microemulsion composition according to claim 1, further comprising.

16. Use of the sorbo surfactant according to claim 1 or any one of claims 3 to 5 for preparing a transparent aqueous flavor microemulsion composition.