Branched alkyl esters of omega-unsaturated carboxylic acids as silicone replacers

Abstract

The present invention lies in the field of cosmetics and provides novel compounds that can serve as silicone replacers in cosmetic applications. Furthermore, cosmetic compositions as well as uses of the disclosed silicone replacers are provided.

Description

[0001] Eisenfuhr Speiser

[0002] Munich, 30. September 2024

[0003] Our Ref.: SM 6974-01 WO SOE / HGR

[0004] Applicant: Symrise AG

[0005] Serial Number: New Application

[0006] Symrise AG

[0007] MuhlenfeldstraBe 1 , 37603 Holzminden,

[0008] Germany

[0009] New cosmetic compounds as silicone replacers

[0010] The present invention lies in the field of cosmetics and provides novel compounds that can serve as silicone replacers in cosmetic applications. Furthermore, cosmetic compositions as well as uses of the disclosed silicone replacers are provided.

[0011] 5 Silicones are a versatile group of synthetic materials derived from silica and are extensively used in cosmetics and personal care products due to their unique properties that enhance formulation and performance. Common types of silicones include dimethicone, cyclomethicone, dimethiconol, amodimethicone, and silicone elastomers. Dimethicone is frequently used for its smooth application and skin0 protection properties, forming a barrier that reduces water loss. Cyclomethicone, a volatile silicone, evaporates quickly, leaving a silky, non-greasy feel without residue. Dimethiconol offers conditioning benefits and is often found in hair care products, while amodimethicone adheres well to hair, providing conditioning and anti-frizz benefits. Silicone elastomers create a gel-like texture, used to thicken5 products and provide a silky, powdery finish in skincare and makeup.

[0012] Silicones offer numerous benefits, such as smooth application, non-comedogenic properties, water resistance, barrier formation, lightweight feel, and improved texture. These properties make them ideal for use in various cosmetic products. In moisturizers, silicones help lock in moisture without feeling heavy or greasy. Primers benefit from silicones by creating a smooth base for makeup application, blurring imperfections, and prolonging the wear of foundation. In foundations, silicones enhance spreadability and provide a flawless finish. Sunscreens utilize silicones to improve water resistance and skin feel, while hair care products benefit from silicones like dimethicone and amodimethicone, which provide shine, reduce frizz, and improve manageability. Anti-aging products also use silicones to fill in fine lines and wrinkles, providing a temporary smoothing effect.

[0013] Despite these benefits, there are some considerations and controversies associated with silicones. Environmental concerns arise because silicones are not biodegradable, raising issues about their impact, particularly in aquatic environments. Additionally, with focus on a more sustainable industry, it is desired to have compounds with the same benefits and conditions as currently available silicones, but can be produced from a natural source. Currently used silicone substances are inorganic synthetic polymers and are not biodegradable.

[0014] The European patent EP 2323969 B1 describes natural esters being an esterification product from undecylenic acid and a vegetable-derived fatty alcohol. The Patent furthermore describes the use of this compound as ingredient in cosmetic compositions as emollient and that the provided compounds have an improved spreadability. The objective technical problem as disclosed in this European patent was to provide esters providing a light skinfeel when incorporated as an emollient into personal care formulations, which meet a “natural” standard.

[0015] Other compounds that can be used as silicone alternatives are mentioned in Goussard, J. M. Aubry, V. Nardello-Rataj, Adv Colloid Interface Sci 2022, 304, 102679 “Bio-based alternatives to volatile silicones: Relationships between chemical structure, physicochemical properties and functional performances" or M. C. Montiel et al., Eng Life Sci. 2019; 19, 370-388 “Biocatalytic solutions to cyclomethicones problem in cosmetics". However, the need for new substances that can serve as silicone replacers is continuously high. It was thus the primary object of the present invention to provide new compounds having desired properties for the use in cosmetic compositions.

[0016] The primary object of this invention was solved by providing a compound of formula

[0017] (I), wherein n is selected from 3 to 11 and, wherein R is selected from a C3 to C8 branched alkyl group, and wherein each branch individually is selected from methyl or ethyl.

[0018] Further objects underlying the present invention follow from the description below and the present patent claims.

[0019] Surprisingly, it was found in terms of the present invention that compounds according to the invention exhibit the same desired properties as petrochemically derived silicones, such as dimethicone, dimethiconol, amodimenthicone and cyclopentosilxane. Thus, the compounds according to the invention can serve as replacers for petrochemically silica-derived silicones in cosmetic compositions. Furthermore, it was observed that the compounds of the present invention could also exhibit superior cosmetic properties in comparing to petrochemically silicaderived silicones.

[0020] A “replacer” in terms of the present invention means a compound having the same or similar properties in comparison to another substance, which should not be used due to toxicological, environmental or health concerns. In terms of the present invention, the inventive compounds described herein should replace cosmetic compounds known in the art as “silicones”, as these substances are not biodegradable and derived from petrochemical origins.

[0021] Preferably, the present invention also relates to mixtures of a compound of formula (I) and isomers thereof. Especially preferably, the ration between compounds of formula (I) and isomers is from 99.9 : 0.1 to 0.1 to 99.9. preferably from 75:25 to 25:75 and especially preferably 70:30.

[0022] The compound according to the invention is an ester derived from an esterification or transesterification process of suitable acids or alcohols. Especially preferably, these compounds are derived from a natural origin and not petrochemically derived.

[0023] Suitable starting materials may be 10-undecylenic acid preferably obtained from castor oil, Isoamyl alcohol and / or 2-ethylhexanol preferably obtained by fermentation of sugar cane, Isobutanol preferably obtained from biotechnological processes or 9-decenoic acid preferably obtained by ethenolysis of oleic acid.

[0024] The terms “petrochemical” or “petrochemically derived” define the source of the educt as originating from natural gas and / or crude oil, i.e. from sources that are not sustainable and will be exhausted in the next few years. A “non-petrochemical” substance is therefore obtained from a natural and not a petrochemical source.

[0025] Methods for determining whether and what proportion of the carbon in a compound is petrochemically and / or non-petrochemically derived are known to the person skilled in the art.

[0026] In the context of the present invention, radiocarbon dating, e.g. according to the ASTM D6866-16 method, is preferably used. The method is based on the observation that the ratio of 12C and 14C is an indicator of non-petrochemical carbon content. Natural sources include renewable and therefore sustainable raw materials so that, in contrast to petrochemical sources, they are (theoretically) not finite but part of the biological carbon cycle. Preferably, the compounds according to the present invention have a natural carbon content of at least 70 %, preferably at least 75 %, preferably at least 80 %, preferably 85 %, further preferably at least 90 %, particularly preferably at least 95 %, further preferably at least 97.5 % and most preferably 100 % of non- petrochemical origin, based on the total carbon content of the respective compound, determined by radiocarbon dating. It is particularly preferred that the compounds according to the present invention are non-petrochemical, i.e. the total carbon of the respective compound is non-petrochemically derived carbon, based on the total carbon content of the respective compound as determined by radiocarbon dating.

[0027] Preferably, the branched alkyl group is branched in alpha, beta and / or gamma position in relation to oxygen.

[0028] Preferably, the branched alkyl group is branched in beta and / or gamma-position in relation to oxygen.

[0029] The branching nomenclature refers to the carbon atoms starting from the oxygen of the compound according to formula (I). The positions referring to the corresponding branches are depicted in formula II exemplarily.

[0030] Preferably, the residue R of formula I is selected from a C4 to C8 branched alkyl group. A C4 to C8 alkyl group in terms of the present invention means an alkyl group having the corresponding number of carbon atoms. In particular a C4 to C8 alkyl group is a butyl, pentyl, hexyl, heptyl or octyl group and a “branched” alkyl group is one of the aforementioned having alkyl branches at one or more carbon atoms.

[0031] Preferably n is selected from an even number between 6 and 10. Especially preferably, n is 8.

[0032] Especially preferably, the cosmetic compound according to formula I is a compound of formula II

[0033]

[0034] For obtaining an ester according to formula II, undecylenic acid may be used as educt, which is derived from castor oil. Castor oil is a vegetable oil pressed from castor beans and thus of natural origin.

[0035] Also, the present invention preferably relates to mixtures comprising at least one compound of formula (II) as well as at least one compound of formula (III) Another aspect of the present invention relates to a cosmetic composition comprising the compound according to the invention. Preferably, the cosmetic composition is a dermatological, skin care or hair care product.

[0036] Also preferably, the cosmetic composition comprises a mixture of compounds of formula (I) and isomers thereof as described herein. Also preferably, the cosmetic composition comprises a mixture of compounds of formula (II) and (III) as described herein. Preferably, the cosmetic composition comprises the compound according to the present invention in an amount of from 0.001 to 100 wt.-%, preferably of from 0.01 to 50 wt.-%, especially preferable of from 0.05 to 20 wt.-% and moreover especially preferable of between 0.1 to 10 wt.-% depending on the total weight of the composition.

[0037] In case, the cosmetic composition comprises the compound according to the present invention in an amount of 100 wt.-%, no other components are present and the compound according to the invention is the cosmetic composition.

[0038] Preferably the composition comprises at least one further substance selected from the group consisting of skin and hair care conditioning agents, skin and hair care softening agents and skin and hair care repairing agents;

[0039] 1.2-alkandiols, preferably selected from the group consisting of 1 ,2-pentanediol,

[0040] 1.2-hexanediol, 1 ,2-heptanediol, 1 ,2-octanediol, 1 ,2-nonanediol and 1 ,2- decanediol or mixtures thereof, preferably wherein the at least one 1 ,2-alkanediol is 1 ,2-pentanediol, 1 ,2-hexanediol, 1 ,2-heptanediol or 1 ,2-octanediol; preservatives, preferably selected from the group consisting of acidic preservatives, parabens or phenylhydroxyalkyl ethers; specifically other cosmetically active substances, preferably selected from the group consisting of abrasives, anti-acne agents and sebum reduction agents, antiaging agents, antibacterial agents, anti-cellulite agents, anti-inflammatory agents, irritation-preventing agents, anti-irritants (anti-inflammatory, irritation-inhibiting and irritation-preventing agents), antioxidants, astringents, antiseptic agents, antistatic agents, binders, buffers, carriers, chelating agents, cell stimulants, cleansing agents, surface-active substances, deodorants and antiperspirants, emulsifiers, enzymes, essential oils, fibers, film formers, fixers, foaming agents, foam stabilizers, antifoaming agents, foam boosters, fungicides, gelling agents and gelforming, moisture regulators, osmolytes, compatible solutes, bleaching agents, optical brightening agents, impregnating agents, turbidity agents, opacifiers, brighteners, polymers, powders, proteins and protein hydrolysates, refattening agents, abrasive agents, skin soothing agents, skin cleansing agents, skin caring agents, skin repair agents, skin whitening agents, skin protecting agents, skin softening agents, skin cooling agents, UV absorbing agents and UV filters, benzylidene-beta-dicarbonyl compounds, alpha-benzoyl cinnamic acid nitriles, detergents, skin tanning agents, thickening agents, vitamins, oils, waxes and fats, phospholipids, fatty acids, surfactants, yeast extracts, extracts of algae or microalgae, electrolytes, liquefiers and organic solvents.

[0041] Preferably, the at least one additional compound is comprised in an amount of from 0.001 to 80 wt.-%, preferably of from 0.002 to 50 wt.-%, particular preferably 0.05 to 30 wt.-% dependent on the total weight of the cosmetic preparation.

[0042] It is preferred that the cosmetic composition according to the invention is of natural origin.

[0043] Preferably, the composition is selected from the group consisting of emulsions, milks, lotions, creams, balms, ointments, gels, tonics, serums, cleansers, granules, powders, stick preparations, leave-on styling products, foams, aerosols, concentrated and / or solid formulations or sprays.

[0044] Moreover preferably, the composition is selected from the group consisting of leave-on or rinse-off personal care products, preferably selected from the group consisting of shampoos, cleansing products, preferably shower gels, body washes and soaps, wet wipes, leave-on and rinse-off conditioners, hair butters and waxes, beard care and hair oils.

[0045] Another aspect of the present invention relates to the use of a compound according to the invention as silicone replacer in cosmetic compositions. Especially preferably, the compound is an ester of formula II.

[0046] Preferably, in terms of the use according to the invention, the cosmetic composition is selected from the group consisting of shampoos, cleansing products, preferably shower gels, body washes and soaps, wet wipes, leave-on and rinse-off conditioners, hair butters and waxes, beard care and hair oils.

[0047] In the following, the invention is further characterized using exemplary, non-limiting examples.

[0048] 1. Instrumental test

[0049] Within the scope of the examples, the inventive compound 1 having the following structural formula (II). The Greek letters a, and y represent the branching positions in relation to oxygen.

[0050] Formula (II)

[0051] The easiness of comb bleached hair when wet and dry was evaluated using the MTT175 from Dia-Stron. Five hair tresses (3 g and 25 cm long) were evaluated per treatment. A standard shampoo formulation was applied to each tress followed by the application of a rinse-off conditioner containing or not 2% of tested compounds. Five measurements were performed for each hair tress. The average energy necessary to comb the tresses (total work) was calculated and the results of the ester or silicone containing treatment groups were compared to that of placebo- treated one. P-values below 0.05 on Student’s T test were considered significant.

[0052] The results are shown below in table 1 . The parameter “compatibility” means the ease of combing.

[0053] Table 1 : Results of compatibility test

[0054] Improvement versus placebo (%)

[0055] „ Combability Wet Combability Dry amp es (Conditioner @2%) (Conditioner @2%)

[0056] Compound 1 18* 15*

[0057] CYCLOPENTASILOXANE -9 -19*

[0058] P=<0.05 2. Sensory test

[0059] Textured hair tresses (curl type IV- 3 g and 17 cm long) were treated with standard shampoo formulation and a rinse-off conditioner containing or not 2% of tested compounds. Sensory attributes of dry hair such as softness, ease of combing, shine, volume and frizz control, and alignment were evaluated by a trained panel (n=15). Scores from 0 (worst possible) to 10 (best possible) were given for each attribute using a 10 cm linear scale. The average score for each attribute was calculated for each treatment and compared with the placebo.

[0060] The results are shown in table 2

[0061] Table 2: Results of the sensory test

[0062] Sensory test: Improvement versus placebo (%);

[0063] Samples (Conditioner .. Ease of . . Volume Frizz . .. .

[0064] @2%) SoftnesscombingShineConlro| Contro|Alignment

[0065] Compound 1 25* 20* 3 61* 48* 42*

[0066] AMODI METH ICON E 5 10 -5 38* -4 5

[0067] CYCLOPENTASILOXANE 5 -6 -8 45* 25* 24*

[0068] DIMETHICONE &

[0069] DIMETHICONOL

[0070] *P<0.05

[0071] 3. Formulation examples

[0072] 3.1 Rinse-off conditioner

[0073] Ingredient Concentration

[0074] (INCI name) (w / w%)

[0075] Aqua q.s. 100

[0076] Disodium EDTA 0.05

[0077] Phenoxyethanol, Hydroxyacetophenone, Caprylyl Glycol, 1.00

[0078] Water (Aqua)

[0079] Behentrimonium Chloride 1.00

[0080] Compound 1 2.00

[0081] Cetearyl Alcohol 4.50

[0082] Ceteareth-20 0.80

[0083] Stearamidopropyl Dimethylamine 0.50

[0084] Capryl ic / Capric triglyceride 3.50

[0085] Citric Acid q.s. pH 3.5-4.5 .2 Pearlized shampoo

[0086] Ingredient Concentration

[0087] (INCI name) (w / w%)

[0088] Aqua q.s. 100

[0089] Disodium EDTA 0.10

[0090] Sodium Laureth Sulfate 25.00

[0091] Acrylates Copolymer 6.50

[0092] Sodium Hydroxide q.s. pH 6.8-7.0

[0093] Cocoamidopropyl Betaine 7.00

[0094] Compound 1 1.00

[0095] Phenoxyethanol, Hydroxyacetophenone, Caprylyl Glycol, 1.00

[0096] Water (Aqua)

[0097] Cocamide MEA 3.00

[0098] Glycol Distearate (and)Sodium Laureth Sulfate (and) 3.00

[0099] Water

[0100] Citric Acid q.s. pH 5.5-6.5

Claims

Claims1. Compound of formula I,wherein n is selected from 3 to 11 and, wherein R is selected from a C3 to C8 branched alkyl group, and wherein each branch is individually selected from methyl or ethyl.

2. Compound according to claim 1, wherein the branched alkyl group is branched in alpha, beta and / or gamma position in relation to oxygen.

3. Compound according to claim 1 or 2, wherein R is selected from a C4 to C8 branched alkyl group.

4. Compound according to any one of the preceding claims, wherein the branched alkyl group is branched in beta and / or gamma-position in relation to oxygen.

5. Compound according to any one of the preceding claims, wherein n is selected from 6 to 10, preferably, wherein n is 8.

6. Compound according to any one of the preceding claims, wherein the compound of formula I is a compound of formula II7. Compound according to any one of the preceding claims, wherein the ester of formula I or formula II is derived from a natural origin.

8. Cosmetic composition comprising the compound according to any one of claims 1 to 7.

9. Cosmetic composition according to claim 8, wherein the compound is comprised in an amount of from 0.001 to 100 wt.-%, preferably of from 0.01 to 50 wt.-%, especially preferable of from 0.05 to 20 wt.-% and moreover especially preferable of between 0.1 to 10 wt.-% depending on the total weight of the composition.

10. Cosmetic composition according to any one of the preceding claims, wherein the composition comprises at least one additional compound selected from the group consisting of preservatives and other cosmetically active substances.

11. Cosmetic composition according to claim 10, wherein the at least one additional compound is comprised in an amount of from 0.001 to 80 wt.-%, preferably of from 0.002 to 60 wt.-%, particular preferably of from 0.05 to 40 wt.-% dependent on the total weight of the cosmetic preparation.

12. Cosmetic composition according to any one of claims 8 to 11 , wherein the preparation is selected from the group consisting of emulsions, milks, lotions, creams, balms, ointments, gels, tonics, serums, cleansers, granules, powders, stick preparations, leave-on styling products, foams, aerosols, concentrated and / or solid formulations or sprays.

13. Cosmetic composition according to any one of claims 8 to 12, wherein the preparation is selected from leave-on or rinse-off personal care products, preferably selected from the group consisting of shampoos, cleansing products, preferably shower gels, body washes and soaps, wet wipes, leave- on and rinse-off conditioners, hair butters and waxes, beard care and hair oils.

14. Use of an ester as defined in any one of claims 1 to 7, preferably a compound of formula (II), as silicone replacer in cosmetic preparations.

15. Use according to claim 14, wherein the cosmetic composition is selected from the group consisting of shampoos, cleansing products, preferably shower gels, body washes and soaps, wet wipes, leave-on and rinse-off conditioners, hair butters and waxes, beard care and conditioners.

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