COSMETIC EMULSION BASES (CEB)

Abstract

At least one embodiment, relates to a method for making cosmetic emulsions comprising the steps of preparing a uniform (suspension) dispersion of at least one water soluble polymer in a mixture containing at least one fatty alcohol. The mixture is to be sufficiently uniform to be processed by flaking, pastillating, prilling or otherwise solidifying the mixture which is then to be added to a cosmetic emulsion oil phase before combining with a water phase.

Claims

1. A method for making cosmetic emulsions comprising: preparing a uniformly dispersed suspension of at least one water soluble polymer in a mixture containing at least one fatty alcohol, and at least one high HLB surfactant the mixture to be sufficiently uniform to be processed by flaking, pastillating, prilling or otherwise solidifying; and adding said mixture to a cosmetic emulsion oil phase.

2. The method as in claim 1, further comprising the step of combining the fatty alcohol mixture with a low HLB surfactant and a high HLB surfactant to form a component in which at least one water soluble polymer is dispersed and suspended with sufficient uniformity then further processed by flaking, pastillating, prilling or otherwise solidifying said mixture which is then to be added to the oil phase of said cosmetic emulsion.

3. The method as in claim 2, wherein a solidified mixture of fatty alcohol, low HLB surfactant and high HLB surfactant with suspended water-soluble polymer is added to a water phase of said cosmetic emulsion.

4. The method of claim 2, wherein the oil phase of said cosmetic emulsion comprises at least one of: preservatives, medicaments, sunscreens, extracts, fragrances, colorants, pigments, clays, waxes, or polymers.

5. The method as in claim 4 wherein the water phase of said cosmetic emulsion comprises at least one of: preservatives, medicaments, sunscreens, extracts, fragrances, colorants, pigments, clays, polymers, humectants, moisturizers, proteins.

6. The process for creating an emulsion as in claim 3, wherein the step of adding the water phase comprises adding a 50% heated water phase.

7. The process as in claim 6, further comprising the step of adding the water phase comprises adding a remaining water phase in a cold form.

8. The method of claim 1. In which the fatty alcohol is cetyl alcohol, stearyl alcohol or a mixture of the two.

9. The method of claim 2. In which the low HLB surfactant is glyceryl monostearate.

10. The method of claim 2. In which the high HLB surfactant is anionic.

11. The method of claim 2. In which the high HLB surfactant is cationic.

12. The method of claim 2. In which the high HLB surfactant is nonionic.

13. A method for making cosmetic emulsions comprising the steps of: providing at least one fatty alcohol; providing at least one low HLB surfactant; providing at least one high HLB surfactant; mixing said at least one fatty alcohol with said at least one low HLB surfactant and said at least one high HLB surfactant together to form a substantially uniformly dispersed mixture; adding at least one water soluble polymer to the uniformly dispersed mixture to form an emulsifier blend; adding the emulsifier blend to a cosmetic emulsion oil phase; and adding the oil phase to the water phase.

14. A method for making cosmetic emulsions comprising the steps of: providing at least one fatty alcohol; providing at least one low HLB surfactant; providing at least one high HLB surfactant; mixing said at least one fatty alcohol with said at least one low HLB surfactant and said at least one high HLB surfactant together to form a substantially uniformly dispersed mixture; adding at least one water soluble polymer to the uniformly dispersed mixture to form an emulsifier blend; adding the emulsifier blend to a cosmetic emulsion water phase.

15. The method as in claim 14, further comprising the step of adding the water phase to the oil phase.

16. The method as in claim 14, further comprising the step of adding the oil phase to the water phase.

17. An emulsifying system comprising: a) an oil in water emulsifier having an HLB of at least 10; b) a fatty alcohol; c) glyceryl monostearate (GMS); and d) a water soluble, emulsion thickening and stabilizing polymer. wherein the system is in the form of a single solid form comprising at least one of a flake or pastille.

18. The emulsifying system as in claim 17, wherein the emulsifying system comprises an emulsifying wax.

19. An emulsifying system comprising a solid blend of at least one fatty alcohol, at least one low HLB surfactant and at least one high HLB surfactant that also contains from 1% to 15% (wt %) of a dispersed water soluble polymer.

20. The system as in claim 19, wherein the solid blend of at least one fatty alcohol, at least one low HLB surfactant and at least one high HLB surfactant that also contains from 2% to 10% (wt %) of a dispersed water soluble polymer.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Other objects and features of the present invention will become apparent from the following detailed description considered in connection with the accompanying drawings which disclose at least one embodiment of the present invention. It should be understood, however, that the drawings are designed for the purpose of illustration only and not as a definition of the limits of the invention.

[0021] In the drawings, wherein similar reference characters denote similar elements throughout the several views:

[0022] FIG. 1 is a listing of ingredients in wt % for a first example;

[0023] FIG. 2 is a listing of ingredients in wt % for examples 2-7;

[0024] FIG. 3 is a listing of ingredients in wt % for examples 8-13;

[0025] FIG. 4 is a listing of ingredients in wt % for examples 14-18;

DETAILED DESCRIPTION

[0026] A test emulsion formula was developed to allow comparison of the stability and physical parameters of the various emulsion bases. The test emulsion formula for a cosmetic lotion is given in Example 1 shown in FIG. 1.

[0027] The Test Lotion Formula (Example 1) is prepared by weighing and combining the Water and Oil phases separately. Both phases are mixed separately and heated to about 65 to 75° C. Triethanolamine (TEA) (or another base of choice) is needed to neutralize the fatty acid (if used—as in the anionic emulsion bases) and the C10-30 Alkyl Acrylates Cross polymer. TEA is not needed for the nonionic or cationic emulsion bases and can be replaced by water. Once both phases are mixed until uniform and at temperature, they are combined by adding the water to the oil phase with mixing. Mixing is continued with the temperature at about 65 to 75° C. for about ½ hour. The Test Lotion is then cooled to the desired drop temperature with mixing.

[0028] Alternatively, the oil phase can be added to the water phase with mixing with both phases at about 65 to 75° C. Mixing is continued for about ½ hour at about 65 to 75° C. and then the Test Lotion is cooled to the desired drop temperature with mixing. In at least one embodiment and as an option to at least one, more than one or all of the examples the water phase can be added as at least a 50% heated water phase. As an option the remaining step of adding water can be in the form of adding cold water for the remaining balance of water.

[0029] As written, the Test Lotion contains 5% Cosmetic Emulsion Base (CEB). This is for purposes of comparing the various CEBs. In practice, the amount can be adjusted to suit the aesthetics and particular needs of the emulsion formulator. For example, if the amount is increased, a thick lotion or a cream instead of a lotion can be produced.

[0030] The Test Lotions were evaluated for pH, viscosity and tested for stability at RT, 50° C. and Freeze/Thaw. Photomicrographs of the emulsions were taken.

[0031] The following examples are provided as illustrations of acceptable and unacceptable emulsion stabilizer systems, but they are not intended to provide a complete listing of all acceptable or unacceptable combinations. The Test Emulsion Formula, as provided in Example 1, is used to make finished emulsions with each of the following examples thus, the Examples can be compared for pH, viscosity, stability, particle size and distribution and aesthetic properties.

Experimental Results

[0032] There are six examples shown in shown in FIG. 2 which include examples 2-7 which are for anionic cosmetic emulsion bases.

[0033] These examples illustrate the concept of combining the high and low HLB surfactants and a stabilizing polymer to form a single composition using anionic high HLB surfactants. Anionic Emulsion Bases can be made with anionic and/or nonionic water soluble polymers. Cationic water soluble polymers will be incompatible.

[0034] The Examples 2, 3 and 6 were made by combining the first four ingredients. These components are heated, with mixing, to about 80 to 85° C., ensuring that all components are melted, then cooling with mixing to 65 to 75° C. The polymer (C10-30 Alkyl Acrylates Cross polymer) is added with mixing and mixed until it is visibly uniform, keeping the temperature at 65 to 75° C. When the mixture was uniform, it was poured onto aluminum foil, allowed to cool to room temperature, removed from the aluminum foil and broken into suitably sized pieces. Examples 4 and 5 were made by combining the first three ingredients, heating, with mixing, to about 80 to 85° C., ensuring that all components were melted, then cooling with mixing to 65 to 75° C. The polymer was added with mixing and mixed until the mixture was uniform. When the mixture was uniform, it was poured onto aluminum foil, allowed to cool to room temperature, removed from the aluminum foil and broken into suitably sized pieces. It was determined that the addition of Glyceryl Tricaprate/caprylate (used in Examples 2 and 3) produced a flake that was too soft and would present difficulties upon storage and shipping. Examples 4, 5 and 6 remedied that, but Example 4 produced an undesirable “rubbery” texture in the Test Lotion (Example 1) upon ageing, while Examples 5 and 6 do not. Example 5 makes a high viscosity lotion (light cream) with acceptable stability. Example 6 allows the Test Lotion (Example 1) to be made without the use of Triethanolamine to neutralize the stearic acid because sufficient base is provided by the sodium stearate to neutralize both the stearic acid and the C10-30 Alkyl Acrylates Cross polymer. If only sodium stearate is used (instead of a combination of stearic acid and sodium stearate, as in Example 6), it reacts with the C10-30 Alkyl Acrylates Cross polymer causing it to precipitate and clump up in the Cosmetic Emulsion Base formula. The Example 7 was made by combining the first four ingredients. These components are heated, with mixing, to about 80 to 85° C., ensuring that all components are melted, then cooling with mixing to 65 to 75° C. The polymer (C10-30 Alkyl Acrylates Cross polymer) is then added with mixing and mixed until it is visibly uniform, keeping the temperature at 65 to 75° C. When the mixture is uniform, it is poured onto aluminum foil, allowed to cool to room temperature, removed from the aluminum foil and broken into suitably sized pieces.

[0035] Example 7 also allows the Test Lotion (Example 1) to be made without the use of Triethanolamine to neutralize the stearic acid because sufficient base is provided by the sodium stearate to neutralize both the stearic acid and the C10-30 Alkyl Acrylates Cross polymer. The Example 7 lotion is stable for 2 months @50° C. and for at least 6 months at Room Temperature.

[0036] FIG. 3 shows the ingredients in wt % for examples 8-13 which are examples of cationic emulsion bases.

[0037] With these examples, the Test Emulsions were evaluated for pH, viscosity and tested for stability at RT, 50° C. and Freeze/Thaw. Photomicrographs of the emulsions were taken.

[0038] These examples illustrate the concept of combining the high and low HLB surfactants and a stabilizing polymer to form a single composition using cationic high HLB surfactants. Cationic Emulsion Bases can be made with cationic and /or nonionic water soluble polymers. Anionic water soluble polymers will be incompatible

[0039] Example 8 was made by combining the first four ingredients then heating with mixing to melt and solubilize them. Once uniform, the mixture was cooled to 65 to 75° C. and the polymer was added with mixing. Once uniform, this mixture was poured onto aluminum foil, allowed to cool to room temperature, removed from the aluminum foil and broken into suitably sized pieces. This formula made too soft a flake and Example 9 was made to correct that by removing the Glyceryl Tricaprate/caprylate and increasing the cationic surfactant and the cetearyl alcohol. Example 9 was made by combining the first three ingredients then heating with mixing to melt and solubilize them. Once uniform, the mixture was cooled to 65 to 75° C. and the polymer was added with mixing. Once uniform, this mixture was poured onto aluminum foil, allowed to cool to room temperature, removed from the aluminum foil and broken into suitably sized pieces. This resulted in a flake that was not uniform because the Polyquaternium 37 formed lumps when mixed with the high and low HLB surfactants. Switching to Guarhydroxypropyltrimonium chloride (Example 10) resolved the lumping problem. Example 10 was made by combining the first three ingredients then heating with mixing to melt and solubilize them. Once uniform, the mixture was cooled to 65 to 75° C. and the polymer was added with mixing. Once uniform, this mixture was poured onto aluminum foil, allowed to cool to room temperature, removed from the aluminum foil and broken into suitably sized pieces. Example 10 produced Test Lotion Formulas that showed signs of instability. Increasing the Behentrimonium chloride and using both Polyquaternium 37 and Guarhydroxypropyltrimonium Chloride gave Example 11—which was made by combining the first three ingredients then heating with mixing to melt and solubilize them. Once uniform, the mixture was cooled to 65 to 75° C. and the (combined) polymers were added with mixing. Once uniform, this mixture was poured onto aluminum foil, allowed to cool to room temperature, removed from the aluminum foil and broken into suitably sized pieces. The Test Lotion Formula for Example 11 produced stable emulsions.

[0040] Example 12 was made to reduce the amount of high HLB surfactant and to increase the viscosity of the Test Lotion Formula. Example 12 was made by combining the first four ingredients then heating with mixing to melt and solubilize them. Once uniform, the mixture was cooled to 65 to 75° C. and the polymers were added with mixing. Once uniform, this mixture was poured onto aluminum foil, allowed to cool to room temperature, removed from the aluminum foil and broken into suitably sized pieces. The Test Lotion Formula DID NOT produce stable emulsions—showing separation at 50° C. after one week and the viscosity was significantly lower than that of Example 11.

[0041] The Test Emulsions were evaluated for pH, viscosity and tested for stability at RT, 50° C. and Freeze/Thaw. Photomicrographs of the emulsions were taken.

[0042] Example 13 discloses the use of Chitosan Citrate as a hydrophilic emulsion stabilizing polymer. The process for making Chitosan Citrate Powder starts with dissolving 5 grams of Chitosan Powder in 90 grams of water with 5 grams of citric acid. When uniform and clear, this mixture is dried for 24 hrs in a 65° C. oven. The brittle solid is then pulverized and classified with a 300 micron screen. The resulting powder is used to make Example 13. The first 3 ingredients are mixed and heated to 90 to 100° C. to completely dissolve all material. Once uniform, the mixture is cooled to 65 to 75° C. and the chitosan citrate powder is added with mixing. Once the mixture is uniform and the polymer powder is evenly dispersed, it is poured onto aluminum foil, allowed to cool to room temperature, removed from the aluminum foil and broken into suitably sized pieces. The test lotion made from Example 13 is stable for 4 weeks at 50° C.

[0043] FIG. 4 shows the ingredients in wt % for examples 14-18 which are for nonionic cosmetic emulsion bases.

[0044] These examples illustrate the concept of combining the high and low HLB surfactants and a stabilizing polymer to form a single composition using nonionic high HLB surfactants. Nonionic Emulsion Bases can be made with cationic, anionic and nonionic water soluble polymers or combinations. However, combinations of anionic and cationic water soluble polymers will generally be incompatible. Note that if anionic or cationic polymers are used, the resulting emulsion blend will not be nonionic.

[0045] The Examples 14 and 15 were made by combining the first four ingredients then heating with mixing to melt and solubilize them. Once uniform, the mixture was cooled to 65 to 75° C. and the polymer was added with mixing. Once uniform, the mixture was poured onto aluminum foil, allowed to cool to room temperature, removed from the aluminum foil and broken into suitably sized pieces. This formula made too soft a flake and the further Examples were made without the Glyceryl Tricaprate/caprylate and with increased cetearyl alcohol. The first attempt with Polysorbate 60 (Example 16) was made by combining the first three ingredients then heating with mixing to melt and solubilize them. Once uniform, the mixture was cooled to 65 to 75° C. and the polymer was added with mixing. Once uniform, the mixture was poured onto aluminum foil, allowed to cool to room temperature, removed from the aluminum foil and broken into suitably sized pieces. Example 16 did not make stable emulsions when used in the Test Lotion Formula (Example 1) without Triethanolamine. The last two Examples (17 and 18) were made by combining the first three ingredients then heating with mixing to melt and solubilize them. Once uniform, the mixture was cooled to 65 to 75° C. and the polymer was added with mixing. Once uniform, the mixture was poured onto aluminum foil, allowed to cool to room temperature, removed from the aluminum foil and broken into suitably sized pieces. The change to Polyglyceryl-10 Stearate (Example 17) produced better stability results with the Test Lotion Formula (Example 1), but ultimately, it was found that reducing the Polyglyceryl-10 Stearate to 15% (Example 18) gave improved stability when used in the Test Lotion Formula.

[0046] The Test Emulsions were evaluated for pH, viscosity and tested for stability at RT, 50° C. and Freeze/Thaw. Photomicrographs of the emulsions were taken.

[0047] Accordingly, while several embodiments of the present invention have been shown and described, it is to be understood that many changes and modifications may be made thereunto without departing from the spirit and scope of the invention as defined in the appended claims.