CALCIUM ALGINATE PARTICLE

Description

[0001] Cosmetic products generally serve not only to make people look beautiful and attractive, but also contribute significantly to increased self-esteem and well-being. Accordingly, a wide variety of cosmetic products are used for the daily cleansing and care of human skin.

[0002] The prior art discloses various cosmetic preparations for the care of human skin. For example, WO 2015 / 169456 A1 discloses cosmetic preparations which have a gel phase in which beads, essentially spherical particles with a size of 0.1 to 20 mm, are suspended. The essentially spherical particles are obtainable by adding alginate (algin) to an emulsion and then dropping the emulsion into a solution containing calcium ions. The interaction of the alginate and the calcium ions leads to immediate and complete gelation of the drop. The essentially spherical particles thus obtained can be removed and suspended in a gel phase. The key advantage of using such particles in cosmetic preparations is that active ingredients can be incorporated into the particles, which might not be stable in the surrounding gel.

[0003] According to WO 2015 / 169456 A1, the cosmetic preparation is contained in a plunger dispenser. Upon removal, the spherical particles are crushed or broken up and mixed with the surrounding gel, forming a homogeneous cosmetic preparation and releasing the active ingredients.

[0004] A disadvantage of the spherical particles or beads disclosed in WO 2015 / 169456 A1 is the fact that they contain silicone oils, particularly cyclomethicone. This ingredient is often no longer desired by many consumers, despite its beneficial effects. Consequently, silicone oils are increasingly being formulated into cosmetic products.

[0005] However, when replacing silicone oils, the skilled person is faced with unforeseen problems that cannot be solved based on their specialist knowledge. If, for example, ester-based oils are used instead of silicone oils to form the alginate-based, essentially spherical emulsion particles, the emulsion components bleed into the aqueous solution containing calcium ions during the described addition of the emulsion to an aqueous solution containing calcium ions to form the particles. This means that the solution containing the calcium ions becomes cloudy. The reason for this is that more components from the emulsion pass into the solution instead of being bound in the formed particles.If the particles are subsequently removed from the solution to be incorporated into a cosmetic preparation, the emulsion originally used is no longer fully converted, so that the loss due to bleeding into the solution increases production costs.

[0006] The object of the present invention was therefore to overcome the described disadvantages of the prior art.

[0007] Furthermore, the skilled person is familiar with document EP 1413298 A1, which discloses calcium alginate-coated macrocapsules produced by a drop-depositing process. However, this document also failed to provide any indication of the present invention.

[0008] Surprisingly, it has now been found that the subject matter of the present invention does not have the disadvantages of the prior art.

[0009] The present invention relates to a process for producing calcium alginate particles containing an emulsion, comprising the following process steps: i. Providing a silicone-free oil-in-water emulsion comprising a. sodium alginate; b. an oil phase containing at least one ester oil, and c. at least one anionic surfactant having an alkyl chain with more than 12 carbon atoms; ii. Providing an aqueous solution containing calcium chloride; iii. Dropping the silicone-free oil-in-water emulsion into the aqueous solution to form the calcium alginate particles.

[0010] A further object of the present invention is a cosmetic product containing the calcium alginate particles produced by the process according to the invention.

[0011] A further object of the present invention are the calcium alginate particles produced by the process according to the invention.

[0012] When added dropwise to an aqueous solution containing at least one calcium salt, the emulsion according to the invention surprisingly shows no bleeding.

[0013] If weight percentages (wt%) are given without reference to a particular composition or specific mixture, these figures always refer to the total weight of the oil-in-water emulsion.

[0014] If ratios of components / substances / groups of substances are disclosed, these ratios refer to weight ratios of the named components / substances / groups of substances.

[0015] The oil-in-water emulsion used according to the invention, hereinafter referred to simply as the emulsion, contains sodium alginate. It is advantageous if the proportion of sodium alginate in the emulsion is from 0.2 to 3 wt.%, preferably from 0.5 to 2 wt.%, and particularly preferably from 0.75 to 1.5 wt.%, whereby the figures refer to the total weight of the emulsion.

[0016] Advantageously, the proportion of the oil phase in the emulsion is from 10 to 25% by weight, preferably from 12 to 20% by weight and in particular from 14 to 18% by weight, whereby the data relate to the total weight of the emulsion and surfactants and emulsifiers are not counted as oil phase by definition.

[0017] By definition, emulsifiers and surfactants are understood to mean all substances listed in the International Cosmetic Ingredient Dictionary and Handbook, Thirteenth Edition 2010, (ISBN 1-882621-47-6) under the name "emulsifying agent and / or surfactant", unless the respective substances are assigned to a different substance class in this disclosure.

[0018] The oil phase of the emulsion used comprises at least one ester oil. Ester oils are esters that are liquid under normal conditions and immiscible with water. The ester oils according to the invention are advantageously selected from the group of triglycerides of linear or branched, saturated or unsaturated, optionally hydroxylated C8-30 fatty acids, as well as esters of branched saturated or unsaturated fatty alcohols with 2-30 carbon atoms with linear or branched saturated or unsaturated fatty acids with 2-30 carbon atoms, provided they are liquid under normal conditions. Preferred ester oils that are liquid at 20°C are selected from the group consisting of isopropyl palmitate, isopropyl stearate, isodecyl neopentanoate, cetearyl isononanoate, C12-15 alkyl benzoate, ethylhexyl stearate, caprylic capric triglyceride, cocoglycerides octyl cocoate, dibutyl adipate and octyl palmitate.It is particularly preferred if at least isodecyl neopentanoate is contained as ester oil.

[0019] It is particularly advantageous if the proportion of ester oils is from 10 to 25% by weight, preferably from 12 to 20% by weight and in particular from 14 to 18% by weight, based on the total weight of the emulsion.

[0020] Furthermore, it is advantageous if the oil phase of the emulsion comprises natural oils, particularly advantageously sunflower, soy, corn germ, almond, olive and / or rapeseed oil.

[0021] Furthermore, the emulsion used according to the invention contains at least one anionic surfactant having an alkyl chain with more than 12 carbon atoms. Such preferred surfactants are characterized by being selected from the group of glutamates, citrates, phosphates, and sulfates.

[0022] Surfactants to be advantageously selected according to the invention are in particular sodium stearoyl glutamate and / or sodium cetearyl sulfate and / or potassium cetyl phosphate, with the use of sodium stearoyl glutamate being particularly preferred.

[0023] Advantageously, the proportion of anionic surfactants having an alkyl chain with more than 12 carbon atoms is from 0.01 to 2.0 wt.%, preferably from 0.04 to 0.9 wt.% and particularly preferably from 0.05 to 0.6 wt.%, based on the total weight of the emulsion.

[0024] It is particularly advantageous if the proportion of sodium stearoyl glutamate and / or sodium cetearyl sulfate is from 0.01 to 0.8 wt.%, preferably from 0.04 to 0.4 wt.% and particularly preferably from 0.05 to 0.2 wt.%, based on the total weight of the emulsion.

[0025] Advantageously, the emulsion used according to the invention does not comprise any non-ionic emulsifiers or surfactants.

[0026] Furthermore, it is advantageous if the emulsion used according to the invention does not contain any anionic surfactants having an alkyl chain with 12 or fewer carbon atoms.

[0027] Furthermore, it is advantageous if the emulsion contains methylpropanediol, preferably in a proportion of 1 to 6% by weight, the percentage by weight relating to the total weight of the emulsion.

[0028] Furthermore, it is advantageous if the emulsion comprises phenoxyethanol, wherein the proportion of phenoxyethanol is preferably from 0.2 to 1 wt.%, based on the total weight of the emulsion.

[0029] Advantageous emulsions are further characterized in that they contain hexanediol, in particular 1,2-hexanediol, wherein the proportion of hexanediol, or the proportion of 1,2-hexanediol, is preferably from 0.3 to 1.5 wt.%, based on the total weight of the emulsion.

[0030] Furthermore, according to the present invention, it is advantageous if the emulsion comprises water in a proportion of at least 70 wt. Advantageously, the water content is from 70 wt.% to 80 wt.%, based on the total weight of the emulsion.

[0031] Furthermore, it is advantageous if the emulsion of the present invention comprises further active ingredients selected from the group consisting of glycyrrhetinic acid, arctiin, folic acid, coenzyme Q10 (ubiquinone), alpha-glucosylrutin, carnitine, carnosine, caffeine, natural and / or synthetic isoflavonoids, glyceryl glucose, creatine, creatinine, taurine, tocopherol, tocopherol acetate, vitamin C, vitamin C phosphate, vitamin C palmitate, niacinamide, vitamin A palmitate, retinol, panthenol, Glycyrrhiza inflata root extract, arctiin, licochalcone A, 4-butylresocinol, N-[(2,4-dihydroxyphenyl)thiazol-2-yl]isobutyramide, honociol and magnolol (also as a component of magnolia extracts), hyaluronic acid and / or silymarin (milk thistle extract).

[0032] Furthermore, it is advantageous if the emulsion of the present invention contains additional UV-A, UV-B, and / or broadband filter substances. Particularly advantageous UV filter substances that are liquid at room temperature within the meaning of the present invention are homomenthyl salicylate (INCI: Homosalate), 2-ethylhexyl 2-cyano-3,3-diphenylacrylate (INCI: Octocrylene), 2-ethylhexyl 2-hydroxybenzoate (2-ethylhexyl salicylate, octyl salicylate, INCI: Octyl Salicylate), and esters of cinnamic acid, preferably 2-ethylhexyl 4-methoxycinnamate (INCI: Octyl Methoxycinnamate).

[0033] Advantageous UV-A filter substances within the meaning of the present invention are dibenzoylmethane derivatives, in particular 4-(tert-butyl)-4'-methoxydibenzoylmethane (CAS No. 70356-09-1), which is sold by Givaudan under the brand name Parsol ®< 1789 and by Merck under the trade name Eusolex ®< 9020.

[0034] Advantageous further UV filter substances within the meaning of the present invention are sulfonated, water-soluble UV filters, such as: Phenylene-1,4-bis-(2-benzimidazyl)-3,3'-5,5'-tetrasulfonic acid and its salts, in particular the corresponding sodium, potassium or triethanolammonium salts, in particular phenylene-1,4-bis-(2-benzimidazyl)-3,3'-5,5'-tetrasulfonic acid bis-sodium salt with the INCI name Bisimidazylate (CAS No.: 180898-37-7), which is available, for example, under the trade name Neo Heliopan AP from Symrise; 1,4-di(2-oxo-10-sulfo-3-bornylidenemethyl)-benzene (also: 3,3'-(1,4-phenylenediethylene)-bis-(7,7-dimethyl-2-oxo-bicyclo-[2.2.1]hept-1-ylmethane sulfonic acid) and its salts (especially the corresponding 10-sulfato compounds, in particular the corresponding sodium, potassium or triethanolammonium salt), which is also known as benzene-1,4-di(2-oxo-3-bornylidenemethyl-10-sulfonic acid). Benzene-1,4-di(2-oxo-3-bornylidenemethyl-10-sulfonic acid) has the INCI name Terephthalidene Dicamphor Sulfonic Acid (CAS. No.: 90457-82-2) and is available, for example, under the trade name Mexoryl SX from Chimex; advantageous broad-spectrum filters are, for example, triazine derivatives, such as 2,4-bis-{[4-(2-ethylhexyloxy)-2-hydroxy]-phenyl}-6-(4-methoxyphenyl)-1,3,5-triazine (INCI: Aniso Triazine), which is available from BASF under the trade name Tinosorb ®< S.

[0035] The emulsion according to the invention is further characterized by being free of silicone oils. Consequently, it contains no oils containing polydimethylsiloxane units.

[0036] Furthermore, it is advantageous if the emulsion is characterized by the fact that it does not contain any mineral oil.

[0037] The aqueous solution containing calcium chloride used according to the invention is advantageously characterized in that it contains calcium chloride in a total proportion of 0.5 to 5 wt.%, preferably 1 to 4 wt.% and particularly preferably 1.5 to 3 wt.%, wherein the wt.% information relates to the total weight of the aqueous solution.

[0038] Furthermore, the aqueous solution according to the invention advantageously comprises 1,2-hexanediol. If the aqueous solution contains 1,2-hexanediol, it is advantageous according to the invention if the proportion of 1,2-hexanediol is from 0.5 to 2 wt.%, based on the total weight of the aqueous solution.

[0039] Furthermore, it is advantageous if the aqueous solution contains methylpropanediol, wherein the proportion of methylpropanediol is preferably in the range of 1 wt.% to 5 wt.% based on the total weight of the aqueous solution.

[0040] It is also advantageous if the aqueous solution contains phenoxyethanol, the proportion of phenoxyethanol preferably being in the range of 0.5 wt.% to 1 wt.% based on the total weight of the aqueous solution.

[0041] It was surprisingly found that when using the process according to the invention, the turbidity in the aqueous phase during particle production is lower than when using a process not according to the invention. This is illustrated by the comparative experiments in the examples.

[0042] According to the invention, it is advantageous if, after the emulsion has been added dropwise to the aqueous solution, the resulting particles remain in the bath for at least 30 minutes to achieve curing. Consequently, the particles become structurally more stable and are less likely to be broken up and / or crushed.

[0043] Furthermore, it is advantageous if the particles are removed from the solution after production, for example advantageously by sieving, and are subsequently suspended in a cosmetic preparation for the production of a cosmetic product.

[0044] It is also advantageous if the particles are washed with demineralized water before being suspended in a cosmetic preparation.

[0045] The preparation and suspension is advantageously carried out at a temperature of 10 to 30°C, whereby the temperature refers to the outside temperature and the temperature of the emulsion and the aqueous solution.

[0046] The resulting particles advantageously have a diameter of 0.1 to 20 mm, preferably 0.5 to 5 mm. The diameter of the particles can be determined by measuring with a caliper or by sieving. Vergleichsversuche und Beispiele

[0047] The following examples are intended to illustrate the present invention without limiting it. Unless otherwise stated, all quantities, proportions, and percentages are based on the weight and the total amount or the total weight of the preparations.

[0048] The spherical particles according to the invention were prepared as follows: First, the following emulsions were prepared, with examples E.1 and E.2 being emulsions according to the invention, while E.3 to E.5 are comparative examples not according to the invention: Inhaltstoff E.1 E.2 E.3 E.4 E.5 Sodium Alginate 1 1 1 1 1 Aqua Ad 100 Ad 100 Ad 100 Ad 100 Ad 100 Cocoglycerides 6 6 6 6 6 Isodecyl Neopentanoate 10 10 10 10 10 1,2- Hexandiol 1 1 1 1 1 Methylpropandiol 4 4 4 4 4 Phenoxyethanol 0,8 0,8 0,8 0,8 0,8 Sodium Stearoyl Glutamate 0,3 - Sodium Cetearyl Sulfate 0,3 Polyglyceryl-3 Methylglucose Distearate 0,3 Sodium Laureth Sulfate 0,3 Polyglyceryl-10 Stearate 0,075

[0049] In addition, an aqueous solution containing the following ingredients was provided: Inhaltsstoffe Wässrige Lösung Aqua Ad 100 1,2-Hexandiol 1 Methylpropanediol 4 Phenoxyethanol 0,8 Calciumchlorid 2

[0050] To prepare the emulsion, the respective emulsion was added dropwise to a beaker containing 250 ml of the aqueous solution using a separating funnel under standard conditions. 50 ml of the emulsion was added dropwise to each beaker. Calcium alginate particles containing the emulsion formed in each sample.

[0051] After sieving out the formed particles, the solution was shaken from the beaker until a homogeneous composition was obtained. A transmission spectrum was immediately recorded at 400 nm using a 1 cm cuvette and a 2 nm slit against water as a reference. The measured values ​​are listed below: Probe Enthaltenes Tensid Transmission bei 400nm E.1 Sodium Stearoyl Glutamate 97 % E.2 Sodium Cetearyl Sulfate 67 % E.3 Polyglyceryl-3 Methylglucose Distearate 18% E.4 Sodium Laureth Sulfate 17% E.5 Polyglyceryl-10 Stearate 2%

[0052] Surprisingly, it was found that using the surfactants according to the invention resulted in significantly lower turbidity, demonstrated by high transmittance. Consequently, bleeding during production was prevented. Non-ionic surfactants / emulsifiers are unsuitable for preventing bleeding (see E.3 and E.5). Other anionic surfactants are also unsuitable (see E.4).

[0053] Further emulsions which can be used according to the invention are listed below. Inhaltstoff E.6 E.7 E.8 E.9 E.10 Sodium Alginate 1 1 1 1 1 Aqua Ad 100 Ad 100 Ad 100 Ad 100 Ad 100 Cocoglycerides 5 16 6 6 Isodecyl Neopentanoate 10 10 Caprylic / Capric Triglyceride 4 3 8 Ethylhexylstearat 4 Isopropylpalmitat 8 8 8 Sonnenblumenöl 0,5 0,5 1,2- Hexandiol 1 1 1 1 1 Methylpropandiol 4 4 4 4 4 Phenoxyethanol 0,8 0,8 0,8 0,8 0,8 Sodium Stearoyl Glutamate 0,3 0,3 0,3 0,3 Sodium Cetearyl Sulfate 0,3 Kalium Cetylphosphate 1,5 Ubichinone 0,1 Klettenfruchtextrakt (Arctiin) 0,3 Ascorbylpalmitat 0,1 Kreatin 0,3 Magnolol 0,1 TiO 2 0,5 Bis-Ethylhexyloxyphenol Methoxyphenyl Triazine 1 0,5 Butyl Methoxydibenzoylmethane 1 0,5 Octocrylene 3 2 Ethylhexyl Salicylate 3 Homosalate 2 Octyl Methoxycinnamate 1

[0054] The respective emulsions E.6 to E.10 were added dropwise under normal conditions using a separating funnel into a beaker filled with 250 ml of the aqueous solution described above. 50 ml of the emulsion was added dropwise to each beaker. Calcium alginate particles containing the emulsion formed in each sample.

Claims

1. Process for producing calcium alginate particles containing an emulsion, comprising the following process steps: i. providing a silicone-free oil-in-water emulsion comprising a. sodium alginate; b. an oil phase containing at least one ester oil, c. at least one anionic surfactant having an alkyl chain with more than 12 carbon atoms; ii. providing an aqueous solution containing calcium chloride iii. adding the silicone-free oil-in-water emulsion dropwise into the aqueous solution to form the calcium alginate particles.

2. Process according to Claim 1, characterized in that the proportion of sodium alginate in the emulsion is from 0.2% to 3% by weight, preferably from 0.5% to 2% by weight and especially preferably from 0.75% to 1.5% by weight, where the figures relate to the total weight of the emulsion.

3. Process according to either of the preceding claims, characterized in that the proportion of the oil phase in the emulsion from 10% to 25% by weight, preferably from 12% to 20% by weight and in particular from 14% to 18% by weight, where the figures relate to the total weight of the emulsion and surfactants and emulsifiers by definition are not considered to be part of the oil phase.

4. Process according to any of the preceding claims, characterized in that at least one ester oil selected from the group of triglycerides of linear or branched, saturated or unsaturated, optionally hydroxylated C8-30 fatty acids, and esters of linear or branched, saturated or unsaturated fatty alcohols with 2 - 30 carbon atoms with linear or branched, saturated or unsaturated fatty acids with 2 - 30 carbon atoms, provided that they are liquid under standard conditions.

5. Process according to any of Claims 1 to 3, characterized in that the at least one ester oil is selected from the group of isopropyl palmitate, isopropyl stearate, Isodecyl Neopentanoate, cetearyl isononanoate, C12-15 alkyl benzoate, ethylhexyl stearate, Caprylic / Capric Triglyceride, octyl cocoate, cocoglycerides, dibutyl adipate and octyl palmitate.

6. Process according to any of the preceding claims, characterized in that the proportion of the ester oils is from 10% to 25% by weight, preferably from 12% to 20% by weight and in particular from 14% to 18% by weight, based on the total weight of the emulsion.

7. Process according to any of the preceding claims, characterized in that the oil phase of the emulsion comprises natural oils, especially advantageously sunflower, soybean, maize germ, almond, olive and / or rapeseed oil.

8. Process according to any of the preceding claims, characterized in that the at least one anionic surfactant having an alkyl chain with more than 12 carbon atoms is selected from the group of glutamates, citrates, phosphates and sulfates.

9. Process according to any of the preceding claims, characterized in that the at least one anionic surfactant having an alkyl chain with more than 12 carbon atoms is selected from Sodium Stearoyl Glutamate and / or Sodium Cetearyl Sulfate and / or Potassium Cetyl Phosphate, with the use of Sodium Stearoyl Glutamate being especially preferred.

10. Process according to any of the preceding claims, characterized in that the proportion of the anionic surfactants having an alkyl chain with more than 12 carbon atoms from 0.01% to 2.0% by weight, preferably from 0.04% to 0.9% by weight and especially preferably from 0.05% to 0.6% by weight, based on the total weight of the emulsion.

11. Process according to any of the preceding claims, characterized in that the emulsion is free of mineral oils.

12. Process according to any of the preceding claims, characterized in that the aqueous solution containing calcium chloride is characterized in that it contains calcium chloride in a total proportion of from 0.5% to 5% by weight, preferably 1% to 4% by weight and especially preferably from 1.5% to 3% by weight, where the figures in % by weight relate to the total weight of the aqueous solution.

13. Particles produced according to any of Claims 1 to 12.

14. Particles according to Claim 13, characterized in that they have a diameter of 0.1-20 mm, preferably 0.5-5 mm.

15. Cosmetic product containing the particles produced according to any of Claims 1 to 12.