Thickening self-invertible inverse latex comprising, as an inverting agent, surfactant species of the polyglycerol ester family, and compositions containing same

Abstract

Disclosed is a self-invertible inverse latex including, as an inverting agent, surfactant species of the polyglycerol ester family; the use thereof as a thickening and/or emulsifying and/or stabilising agent for a cosmetic, dermopharmaceutical or pharmaceutical topical composition, and cosmetic, dermopharmaceutical or pharmaceutical topical compositions containing same. Also disclosed is a new surfactant composition containing polyglycerol esters.

Claims

1. A self-invertible inverse latex of a crosslinked anionic polyelectrolyte (P) comprising, per 100 mol %: (a.sub.1)—of a proportion of greater than or equal to 30 mol % and less than 100 mol % of monomer units resulting from 2-methyl-2-[(1-oxo-2-propenyl)amino]-1-propanesulfonic acid in free acid or partially or totally salified form; (a.sub.2)—of a proportion of greater than 0 mol % and less than or equal to 70 mol % of monomer units resulting from at least one monomer chosen from the elements of the group consisting of acrylic acid, methacrylic acid, 2-(carboxyethyl)acrylic acid, itaconic acid, maleic acid and 3-methyl-3-[(1-oxo-2-propenyl)amino]butanoic acid, the carboxyl functional group of said monomers being in the free acid, partially salified or completely salified form, and/or from the elements of the group consisting of 2-hydroxyethyl acrylate, 2,3-dihydroxypropyl acrylate, 2-hydroxyethyl methacrylate, 2,3-dihydroxypropyl methacrylate, or vinylpyrrolidone; (a.sub.3)—of a proportion of greater than 0 mol % and less than or equal to 1 mol % of monomer units resulting from at least one diethylenic or polyethylenic crosslinking monomer (AR); the sum of said molar proportions of monomer units according to a.sub.1), a.sub.2) and a.sub.3) being equal to 100 mol %; said self-invertible inverse latex being an emulsion of water-in-oil (W) comprising, per 100% of its weight: a)—from 10% by weight to 90% by weight of said crosslinked anionic polyelectrolyte (P); b)—from 5% by weight to 50% by weight of a fatty phase constituted of at least one oil (O); c)—from 1% by weight to 50% by weight of water; d)—from 0.5% by weight to 10% by weight of an emulsifying system of water-in-oil (S.sub.1); and e)—from 2% by weight to 10% by weight of an emulsifying system of oil-in-water (S.sub.2); the sum of the proportions by weight of a), b), c), d) and e) being equal to 100% by weight; wherein said emulsifying system of oil-in-water (S.sub.2) comprises, per 100% of its weight: f)—a proportion of greater than or equal to 50% by weight and less than or equal to 100% of a composition (C.sub.e) which comprises, per 100% of its weight; e.sub.1)—from 5% by weight to 15% by weight of at least one compound of formula (I):
HO—[CH.sub.2—CH(OH)—CH.sub.2—O].sub.n—H  (I) in which n represents an integer greater than or equal to 1 and less than or equal to 15; e.sub.2)—from 60% by weight to 80% by weight of at least one compound of formula (II):
R.sub.1—(C═O)—[O—CH.sub.2—CH(OH)—CH.sub.2].sub.p—OH  (II), in which p, which is different from or identical to n, represents an integer greater than or equal to 1 and less than or equal to 15; and in which the R.sub.1—(C═O)— group represents a saturated or unsaturated and linear or branched aliphatic radical comprising from 6 to 22 carbon atoms; and e.sub.3)—from 5% to 15% by weight of at least one composition (C.sub.11) represented by the formula (III):
HO—[CH.sub.2—CHOH—CH.sub.2—O-].sub.q-(G).sub.r-H  (III), in which q, which is different from or identical to n, represents an integer greater than or equal to 1 and less than or equal to 3, G represents the residue of a reducing sugar and r represents a decimal number greater than or equal to 1.05 and less than or equal to 5.00; said composition (C.sub.11) consisting of a mixture of the compounds of formulae (III.sub.1), (III.sub.2), (III.sub.3), (III.sub.4) and (III.sub.5):
HO—[CH.sub.2—CHOH—CH.sub.2—O—].sub.q—O-(G).sub.1-H  (III.sub.1),
HO—[CH.sub.2—CHOH—CH.sub.2—O—].sub.q—O-(G).sub.2-H  (III.sub.2),
HO—[CH.sub.2—CHOH—CH.sub.2—O—].sub.q—O-(G).sub.3-H  (III.sub.3),
HO—[CH.sub.2—CHOH—CH.sub.2—O—].sub.q—O-(G).sub.4-H  (III.sub.4),
HO—[CH.sub.2—CHOH—CH.sub.2—O—].sub.q—O-(G).sub.5-H  (III.sub.5), in molar proportions of said compounds of formulae (III.sub.1), (III.sub.2), (III.sub.3), (III.sub.4) and (III.sub.5) respectively equal to a.sub.1, a.sub.2, a.sub.3, a.sub.4 and a.sub.5, such that the sum (a.sub.1+a.sub.2+a.sub.3+a.sub.4+a.sub.5) is equal to 1, and that the sum (a.sub.1+2a.sub.2+3a.sub.3+4a.sub.4+5a.sub.5) is equal to r; the sum of the proportions by weight of e.sub.1), e.sub.2) and e.sub.3) being equal to 100% by weight.

2. The self-invertible inverse latex as defined in claim 1, wherein said crosslinked anionic polyelectrolyte (P) is a a copolymer of 2-methyl-2-[(1-oxo-2-propenyl)amino]-1-propanesulfonic acid and of acrylic acid which are partially or completely salified in the sodium salt or ammonium salt form, crosslinked by triallylamine and/or methylenebis(acrylamide); a copolymer of 2-methyl-2-[(1-oxo-2-propenyl)amino]-1-propanesulfonic acid (γ) partially or completely salified in the sodium salt form and of acrylic acid (δ) partially or completely salified in the sodium salt form in a molar ratio (γ)/(δ) of greater than or equal to 30/70 and less than or equal to 90/10, crosslinked by triallylamine and/or methylenebis(acrylamide); or a copolymer of 2-methyl-2-[(1-oxo-2-propenyl)amino]-1-propanesulfonic acid (γ) partially or completely salified in the sodium salt form and of acrylic acid (δ) partially or completely salified in the sodium salt form in a molar ratio (γ)/(δ) of greater than or equal to 40/60 and less than or equal to 90/10, crosslinked by triallylamine and/or methylenebis(acrylamide).

3. The self-invertible inverse latex as defined in either claim 1, wherein, in the formula (I) as defined above, n represents an integer greater than or equal to 1 and less than or equal to 10, and wherein, in the formula (II) as defined above, p, which is identical to or different from n, represents an integer greater than or equal to 1 and less than or equal to 10, and the R.sub.1—(C═O)— group is chosen from octanoyl, decanoyl, W-undecylenoyl, dodecanoyl, tetradecanoyl, hexadecanoyl, octadecanoyl, 9-octadecenoyl or 9,12-octadecadienoyl radicals.

4. The self-invertible inverse latex as defined in claim 1, wherein, in said emulsifying system of oil-in-water (S.sub.2), said composition (C.sub.e) as defined above consists of, per 100% of its weight: e.sub.1)—from 5% by weight to 15% by weight of at least one compound of formula (I): as defined above; e.sub.2)—from 60% by weight to 80% by weight of at least one compound of formula (II) as defined above; and e.sub.3)—from 5% to 15% by weight of at least one composition (C.sub.11) represented by the formula (III):
HO—[CH.sub.2—CHOH—CH.sub.2—O-].sub.q-(G).sub.r-H  (III), in which q, which is different from or identical to n, represents an integer greater than or equal to 1 and less than or equal to 3, G represents the residue of a reducing sugar and r represents a decimal number greater than or equal to 1.05 and less than or equal to 5.00; said composition (C.sub.11) consisting of a mixture of the compounds of formulae (III.sub.1), (III.sub.2), (III.sub.3), (III.sub.4) and (III.sub.5):
HO—[CH.sub.2—CHOH—CH.sub.2—O—].sub.q—O-(G).sub.1-H  (III.sub.1),
HO—[CH.sub.2—CHOH—CH.sub.2—O—].sub.q—O-(G).sub.2-H  (III.sub.2),
HO—[CH.sub.2—CHOH—CH.sub.2—O—].sub.q—O-(G).sub.3-H  (III.sub.3),
HO—[CH.sub.2—CHOH—CH.sub.2—O—].sub.q—O-(G).sub.4-H  (III.sub.4),
HO—[CH.sub.2—CHOH—CH.sub.2—O—].sub.q—O-(G).sub.5-H  (III.sub.5), in molar proportions of said compounds of formulae (III.sub.1), (III.sub.2), (III.sub.3), (III.sub.4) and (III.sub.5) respectively equal to a.sub.1, a.sub.2, a.sub.3, a.sub.4 and a.sub.5, such that the sum (a.sub.1+a.sub.2+a.sub.3+a.sub.4+a.sub.5) is equal to 1, and that the sum (a.sub.1+2a.sub.2+3a.sub.3+4a.sub.4+5a.sub.5) is equal to r; the sum of the proportions by weight of e.sub.1), e.sub.2) and e.sub.3) being equal to 100% by weight.

5. The self-invertible inverse latex as defined in claim 1, wherein, in the formula (III) as defined above, q is equal to 1, G represents the residue of glucose and r represents a decimal number greater than or equal to 1.05 and less than or equal to 2.5.

6. The self-invertible inverse latex as defined in claim 2, wherein, in the formula (I) as defined above, n represents an integer greater than or equal to 1 and less than or equal to 10, and wherein, in the formula (II) as defined above, p, which is identical to or different from n, represents an integer greater than or equal to 1 and less than or equal to 10, and the R1-(C═O)—group is chosen from octanoyl, decanoyl, ω-undecylenoyl, dodecanoyl, tetradecanoyl, hexadecanoyl, octadecanoyl, 9-octadecenoyl or 9,12-octadecadienoyl radicals.

7. A self-invertible inverse latex of a crosslinked anionic polyelectrolyte (P) comprising, per 100 mol %: (a.sub.1)—of a proportion of greater than or equal to 30 mol % and less than 100 mol % of monomer units resulting from 2-methyl-2-[(1-oxo-2-propenyl)amino]-1-propanesulfonic acid in free acid or partially or totally salified form; and (a.sub.2)—of a proportion of greater than 0 mol % and less than or equal to 1 mol % of monomer units resulting from at least one diethylenic or polyethylenic crosslinking monomer (AR); the sum of said molar proportions of monomer units according to a.sub.1) and a.sub.2) being equal to 100 mol %; said self-invertible inverse latex being an emulsion of water-in-oil (W) comprising, per 100% of its weight: a)—from 10% by weight to 90% by weight of said crosslinked anionic polyelectrolyte (P); b)—from 5% by weight to 50% by weight of a fatty phase constituted of at least one oil (O); c)—from 1% by weight to 50% by weight of water; d)—from 0.5% by weight to 10% by weight of an emulsifying system of water-in-oil (S.sub.1); and e)—from 2% by weight to 10% by weight of an emulsifying system of oil-in-water (S.sub.2); the sum of the proportions by weight of a), b), c), d) and e) being equal to 100% by weight; wherein said emulsifying system of oil-in-water (S.sub.2) comprises, per 100% of its weight: f)—a proportion of greater than or equal to 50% by weight and less than or equal to 100% of a composition (C.sub.e) which comprises, per 100% of its weight; e.sub.1)—from 5% by weight to 15% by weight of at least one compound of formula (I):
HO—[CH.sub.2—CH(OH)—CH.sub.2—O].sub.n—H  (I) in which n represents an integer greater than or equal to 1 and less than or equal to 15; and e.sub.2)—from 60% by weight to 80% by weight of at least one compound of formula (II):
R.sub.1—(C═O)—[O—CH.sub.2—CH(OH)—CH.sub.2].sub.p—OH  (II), in which p, which is different from or identical to n, represents an integer greater than or equal to 1 and less than or equal to 15; and in which the R.sub.1—(C═O)— group represents a saturated or unsaturated and linear or branched aliphatic radical comprising from 6 to 22 carbon atoms; and e.sub.3)—from 5% to 15% by weight of at least one composition (C.sub.11) represented by the formula (III):
HO—[CH.sub.2—CHOH—CH.sub.2—O-].sub.q-(G).sub.r-H  (III), in which formula (III) q, which is different from or identical to n, represents an integer greater than or equal to 1 and less than or equal to 3, G represents the residue of a reducing sugar and r represents a decimal number greater than or equal to 1.05 and less than or equal to 5.00, said composition (C.sub.11) consisting of a mixture of the compounds of formulae (III.sub.1), (III.sub.2), (III.sub.3), (III.sub.4) and (III.sub.5):
HO—[CH.sub.2—CHOH—CH.sub.2—O—].sub.q—O-(G).sub.1-H(III.sub.1),
HO—[CH.sub.2—CHOH—CH.sub.2—O—].sub.q—O-(G).sub.2-H(III.sub.2),
HO—[CH.sub.2—CHOH—CH.sub.2—O—].sub.q—O-(G).sub.3-H(III.sub.3),
HO—[CH.sub.2—CHOH—CH.sub.2—O—].sub.q—O-(G).sub.4-H(III.sub.4),
HO—[CH.sub.2—CHOH—CH.sub.2—O—].sub.q—O-(G).sub.5-H(III.sub.5), in molar proportions of said compounds of formulae (III.sub.1), (III.sub.2), (III.sub.3), (III.sub.4) and (III.sub.5) respectively equal to a.sub.1, a.sub.2, a.sub.3, a.sub.4 and a.sub.5, such that the sum a.sub.1+a.sub.2+a.sub.3+a.sub.4+a.sub.5 is equal to 1, and that the sum a.sub.1+2a.sub.2+3a.sub.3+4a.sub.4+5a.sub.5 is equal to r; the sum of the proportions by weight of e.sub.1), e.sub.2) and e.sub.3) being equal to 100% by weight.

8. A thickening and/or emulsifying and/or stabilizing agent for a topical cosmetic composition, comprising said self-invertible inverse latex as defined in claim 1.

9. A topical cosmetic composition (F), comprising, as thickening agent, per 100% of its total weight, between 0.1% and 10% by weight of said self-invertible inverse latex as defined in claim 1.

10. A topical pharmaceutical composition (G), comprising, as thickening agent, per 100% of its total weight, between 0.1% and 10% by weight of said self-invertible inverse latex as defined in claim 1.

Description

DESCRIPTION OF THE PREFERRED EMBODIMENTS

(1) The following examples illustrate the invention without, however, limiting it.

I—Preparation of Surface-Active Compositions According to the Invention and Comparative Compositions

I.SUB.A.—Preparation of a Composition Comprising Glyceryl Polyglucoside and Glycerol

(2) 650 grams of glycerol, i.e. 5 molar equivalents, are introduced into a jacketed glass reactor provided with efficient stirring, in which jacket a heat-exchange fluid circulates. The glycerol is brought to a temperature of approximately 100° C.

(3) 423.9 grams, i.e. 1 molar equivalent, of glucose are then gradually added to the reaction medium in order to allow it to homogeneously disperse. An acidic catalytic system consisting of 0.51 gram of 98% sulfuric acid is added to the mixture thus obtained.

(4) The reaction medium is placed under a partial vacuum at 30 mbars, and maintained at a temperature of 100° C.-105° C. for a period of time of four hours, with evacuation of the water formed by means of a distillation assembly.

(5) The reaction medium is subsequently cooled to 95° C.-100° C. and neutralized by addition of 30% sodium hydroxide, in order to bring the pH of a 1% solution of this mixture to a value of approximately 7.0.

(6) The reaction mixture is emptied in order to obtain the composition referenced (E.sub.IB).

(7) The analytical characteristics of the composition (E.sub.IB) thus obtained are as follows: Appearance (visual): clear liquid; pH 1% solution: 6.8; Residual glycerol: 55.1%; Residual glucose: <1%; Glyceryl polyglucosides: 44.7%

I.SUB.B.—Preparation of the Composition (EM.SUB.2.) Based on Decaglycerol Laurate (EM.SUB.1.) and on Hexaglycerol

(8) 71.5 grams of decaglycerol monolaurate sold under the brand name Decaglyn 1-L (hereinafter denoted by the term “Composition (EM.sub.1)”) and 28.5 grams of polyglycerol-6 (sold under the brand name Polyglycerol 6™ by Spiga) are introduced into a jacketed glass reactor provided with efficient mechanical stirring, in which jacket a heat-exchange fluid circulates, at a temperature of 35° C. under mechanical stirring of anchor type at a speed of 80 revolutions/minute. After mixing under such conditions for 30 minutes, the mixture is emptied in order to obtain the composition (EM.sub.2).

I.SUB.C.—Preparation of the Composition (EM.SUB.3.) Based on Decaglycerol Laurate (EM.SUB.1.) and on Decaglycerol

(9) 71.5 grams of decaglycerol monolaurate sold under the brand name Decaglyn 1-L (hereinafter denoted by the term “Composition (EM.sub.1)”) and 28.5 grams of polyglycerol-10 (sold under the brand name Polyglycerin 10™) are introduced into a jacketed glass reactor provided with efficient mechanical stirring, in which jacket a heat-exchange fluid circulates, at a temperature of 35° C. under mechanical stirring of anchor type at a speed of 80 revolutions/minute.

(10) After mixing under such conditions for 30 minutes, the mixture is emptied in order to obtain the composition (EM.sub.3).

I.SUB.D.—Preparation of the Composition (EM.SUB.4.) Based on Decaglycerol Laurate (EM.SUB.1.), on Glyceryl Polyglucoside and on Glycerol (E.SUB.IB.)

(11) 71.5 grams of decaglycerol monolaurate sold under the brand name Decaglyn 1-L (hereinafter denoted by the term “Composition (EM.sub.1)”) and 28.5 grams of the composition (E.sub.IB), the preparation of which is described above, are introduced into a jacketed glass reactor provided with efficient mechanical stirring, in which jacket a heat-exchange fluid circulates, at a temperature of 35° C. under mechanical stirring of anchor type at a speed of 80 revolutions/minute. After mixing under such conditions for 30 minutes, the mixture is emptied in order to obtain the composition (EM.sub.4).

I.SUB.E.—Preparation of the Composition (EM.SUB.5.) Based on Decaglycerol Laurate (EM.SUB.1.) and on Glycerol

(12) 71.5 grams of decaglycerol monolaurate sold under the brand name Decaglyn 1-L (hereinafter denoted by the term “Composition (EM.sub.1)”) and 28.5 grams of glycerol are introduced into a jacketed glass reactor provided with efficient mechanical stirring, in which jacket a heat-exchange fluid circulates, at a temperature of 35° C. under mechanical stirring of anchor type at a speed of 80 revolutions/minute. After mixing under such conditions for 30 minutes, the mixture is emptied in order to obtain the composition (EM.sub.5).

(13) The analytical characteristics of the compositions (EM.sub.1), (EM.sub.2), (EM.sub.3), (EM.sub.4), (EM.sub.5) and (EM.sub.6) are recorded in table 1 below.

(14) TABLE-US-00001 TABLE 1 Proportions of constituents Emulsifying composition (% by weight) (EM.sub.1) (EM.sub.2) (EM.sub.3) (EM.sub.4) (EM.sub.5) Decaglycerol monolaurate 100% 71.5% 71.5% 71.5% 71.5% Proportion by weight of  0% 28.5   0%   0%   0% hexaglycerol Proportion by weight of  0%   0% 28.5     0%   0% decaglycerol Proportion by weight of  0%   0%   0% 12.8%   0% glyceryl polyglucoside Proportion by weight of  0%   0%   0% 15.7% 28.5   glycerol

II—Preparation and Evaluation of Self-Invertible Inverse Latexes of a Crosslinked Copolymer of the Sodium Salt of 2-methyl-[(1-oxo-2-propenyl)amino]-1-propanesulfonic Acid and of Partially Salified Acrylic Acid

(15) An aqueous phase is prepared by successively pouring, into a beaker and with stirring, 75.4 grams of glacial acrylic acid, 577.5 grams of a 55% aqueous solution of sodium salt of 2-methyl-[(1-oxo-2-propenyl)amino]-1-propanesulfonic acid, 42.5 grams of a 48% by weight aqueous sodium hydroxide solution, 0.45 gram of a commercial 40% by weight aqueous sodium diethylenetriaminepentaacetate solution and 0.167 gram of methylenebis(acrylamide). The pH of this aqueous phase is subsequently adjusted to 5.5.

(16) Independently, an organic phase is prepared by mixing 208 grams of the mixture of alkanes sold under the brand name Emogreen™ L15, 14 grams of Montane™ 80, 9.5 grams of Montane™ 70 and 0.2 gram of azobis(isobutyronitrile) (AIBN).

(17) The aqueous phase prepared is subsequently gradually added to the oily phase and then dispersed using a rotor-stator of Ultra-Turrax type sold by IKA.

(18) The emulsion obtained is transferred into a reactor in order to be subjected to sparging with nitrogen in order to remove the oxygen and cooled to approximately 5-6° C. 5 cm.sup.3 of a 0.42% by weight solution of cumene hydroperoxide in Emogreen™ L15 are added to the emulsion which is kept stirred, followed by gradual introduction of a 0.1% by weight aqueous sodium metabisulfite solution at a flow rate of 0.5 cm.sup.3 per minute, in order to initiate the polymerization reaction. The temperature of the medium increases until a stationary phase is reached. The reaction medium is subsequently heated at 85° C. for 1 hour and then the combined mixture is cooled down to approximately 35° C. in order to obtain the mixture denoted (M.sub.2).

(19) The mixture (M.sub.2) obtained above is divided up into different portions, to which the different surface-active compositions (EM.sub.1), (EM.sub.2), (EM.sub.3), (EM.sub.4) and (EM.sub.5), as described above, preheated to 60° C., are added in proportions by weight as shown in table 2 below.

(20) The self-invertible inverse latexes resulting from these mixtures are respectively denoted (IL.sub.1), (IL.sub.2), (IL.sub.3), (IL.sub.4) and (IL.sub.5) and are evaluated by the observation of their appearance at 25° C., by the rate of inversion during the preparation of an aqueous gel comprising 2% by weight of self-invertible inverse latex and by the viscosity of this aqueous gel comprising 2% by weight of a self-invertible inverse latex.

(21) The method for evaluation of the duration of inversion of the self-invertible inverse latexes consists in introducing, into a 2 liter beaker, the amount of water necessary for the preparation of 800 grams of an aqueous gel. A mechanical helical stirrer of Turbotest™ type, version 2004, sold by VMI, connected to a motor, is placed toward the bottom of the beaker. Stirring is started at a speed of 900 revolutions/minute and the necessary amount of self-invertible inverse latex to be evaluated is introduced into the beaker with stirring. This stirring creates a vortex which disappears when the polymer inverts and the gel is formed. The duration of inversion, measured in seconds, of the self-invertible inverse latexes corresponds to the time elapsed between the start of the addition of the self-invertible inverse latex tested and the disappearance of the vortex, resulting in a smooth gel, devoid of lumps, being obtained. This evaluation is carried out on conclusion of the manufacture of the inverse latexes tested (t=0) and then after a period of storage at 25° C. of 3 months (t=3 months). The results obtained are recorded in table 2 below. The viscosity of an aqueous gel comprising 2% by weight of self-invertible inverse latex (μ) is measured at t=0 and then at t=3 months, by means of a Brookfield RVT viscometer (Spindle 6 Speed 5). Likewise, the appearance of the self-invertible inverse latex is evaluated visually at t=0.

(22) TABLE-US-00002 TABLE 2 Self-invertible inverse latexes (IL.sub.1) (IL.sub.2) (IL.sub.3) (IL.sub.4) (IL.sub.5) Reference of the surface-active composition tested (EM.sub.1) (EM.sub.2) (EM.sub.3) (EM.sub.4) (EM.sub.5) Amount tested 5% 7% 7% 7% 7% (EM.sub.i)/(IL.sub.i) (% by weight) Measurements at t = 0 μ (in mPa .Math. s) 120 000 116 000 104 000 98 000 104 000 Duration of inversion 130 s 38 s 38 s 60 s 16 s Appearance of the Lme* Lme* Lme* Lme* Lme* self-invertible latex at 25° C. Measurements at t = 3 months (3 M) μ (in mPa .Math. s)  97 000  98 000 100 000 94 000  95 000 Duration of inversion 151 s 55 s 78 s 78 s 17 s Lme*: Liquid milky emulsion

(23) The self-invertible inverse latexes (IL.sub.2), (IL.sub.3), (IL.sub.4) and (IL.sub.5) according to the invention and devoid of alkoxylated derivatives and more particularly of ethoxylated derivatives make it possible to obtain smooth gels, with a duration of inversion far lower than that observed for the self-invertible inverse latex (IL.sub.1), comprising only decaglycerol monolaurate alone as constituent of the inverting surface-active system, while retaining excellent thickening properties. Furthermore, they are characterized by a better reproducibility of the rate of inversion and of the thickening properties after storage for three months than for the comparative self-invertible inverse latex (IL.sub.1).

III—Preparation and Evaluation of Self-Invertible Inverse Latexes of a Crosslinked Copolymer of the Sodium Salt of 2-methyl-[(1-oxo-2-propenyl)amino]-1-propanesulfonic Acid and of Partially Salified Acrylic Acid

(24) Example II, described above, is repeated, the 208 grams of Emogreen™ L15 being replaced with 208 grams of isohexadecane, in order to obtain the mixture denoted (M.sub.3), which is divided up into different portions, to which the different surface-active compositions (EM.sub.1), (EM.sub.2) and (EM.sub.3), as described above, preheated to 60° C., are added in proportions by weight as shown in table 3 below. The self-invertible inverse latexes resulting from these mixtures are respectively denoted (IL.sub.6), (IL.sub.7) and (IL.sub.8) and are evaluated by the observation of their appearance at 25° C., by the rate of inversion during the preparation of an aqueous gel comprising 2% by weight of self-invertible inverse latex (the method of which is described above) and by the viscosity of this aqueous gel comprising 2% by weight of a self-invertible inverse latex (μ; Brookfield RVT viscometer (Spindle 6 Speed 5)). This evaluation is carried out on conclusion of the manufacture of the inverse latexes tested (t=0) and then after a period of storage at 25° C. of 3 months (t=3 months).

(25) The results obtained are recorded in table 3 below.

(26) TABLE-US-00003 TABLE 3 Self-invertible inverse latexes (IL.sub.6) (IL.sub.7) (IL.sub.8) Surface-active composition tested (EM.sub.1) (EM.sub.2) (EM.sub.3) Amount tested (EM.sub.i)/(IL.sub.i) 5% 7% 7% (% by weight) Measurements at t = 0 μ (in mPa .Math. s) 108 000 106 000 110 000 Duration of inversion 125 s 60 s 25 s Appearance of the self-invertible Lme* Lme* Lme* latex at 25° C. Measurements at t = 3 months μ (in mPa .Math. s)  97 000 102 000 105 000 Duration of inversion 155 s 70 s 72 s Lme*: Liquid milky emulsion

(27) The self-invertible inverse latexes (IL.sub.7) and (IL.sub.8) according to the invention and devoid of alkoxylated derivatives and more particularly of ethoxylated derivatives make it possible to obtain smooth gels, with a duration of inversion far lower than that observed for the self-invertible inverse latex (IL.sub.6), comprising only decaglycerol monolaurate alone as constituent of the inverting surface-active system, while retaining excellent thickening properties. Furthermore, they are characterized by a better reproducibility of the rate of inversion and of the thickening properties after storage for three months than for the comparative self-invertible inverse latex (IL.sub.1).

IV: Illustrative Cosmetic Formulations

(28) In the following formulations, the percentages are expressed as percentage by weight per 100% of the weight of the formulation.

Example IV-1

Care Cream

(29) Cyclomethicone: 10% Self-invertible inverse latex (IL.sub.2): 0.8% Montanov™ 68: 2% Stearyl alcohol: 1% Stearic alcohol: 0.5% Preservative: 0.65% Lysine: 0.025% EDTA (disodium salt): 0.05% Xanthan gum: 0.2% Glycerol: 3% Water: q.s. for 100%

Example IV-2

Antisun Milk

(30) Formula

(31) A Montanov™ 68: 3.0% Sesame oil: 5.0% Parsol™ MCX: 5.0% λ-Carrageenan: 0.10% B Water: q.s. for C Self-invertible inverse latex (IL.sub.3): 0.80% D Fragrance: q.s. Preservative: q.s.
Procedure

(32) Emulsify B in A at 60° C., then add C at approximately 60° C., then D at approximately 30° C. and adjust the pH, if necessary.

Example IV-3

Body Milk

(33) Montanov™ 202: 3.5% Lanol™ 37T: 8.0% Solagum™ L: 0.05% Water: q.s. for Benzophenone-3: 2.0% Dimethicone 350 cPs: 0.05% Self-invertible inverse latex (IL.sub.2): 2.5% Preservative: 0.2% Fragrance: 0.4%

Example IV-4

Makeup-Removing Emulsion Comprising Sweet Almond Oil

(34) Montanov™ 202: 5% Sweet almond oil: 5% Water: q.s. for 100% Self-invertible inverse latex (IL.sub.2): 0.3% Glycerol: 5% Preservative: 0.2% Fragrance: 0.3%

Example IV-5

Moisturizing Cream for Greasy Skin

(35) Montanov™ 68: 5% Cetylstearyl octanoate: 8% Octyl palmitate: 2% Water: q.s. for 100% Self-invertible inverse latex (IL.sub.4): 2.6% Micropearl™ M100: 3.0% Mucopolysaccharides: 5% Sepicide™ HB: 0.8% Fragrance: 0.3%

Example IV-6

Makeup-Removing Milk

(36) Montanov™ 68: 3% Primol™ 352: 8.0% Sweet almond oil: 2% Water: q.s. for 100% Self-invertible inverse latex (IL.sub.2): 0.8% Preservative: 0.2%

Example IV-7

Antisun Milk

(37) Montanov™ L: 3.5% Lanol™ 37T: 10.0% Parsol™ MCX: 5.0% Eusolex™ 4360: 2.0% Water: q.s. for 100% Self-invertible inverse latex (IL.sub.2): 1.8% Preservative: 0.2% Fragrance: 0.4%

Example IV-8

Sunless Tanning Emulsion

(38) Lanol™ 99: 15% Montanov™ 68: 3.0% Parsol™ MCX: 3.0% Water: q.s. for 100% Dihydroxyacetone: 5.0% Monosodium phosphate: 0.2% Self-invertible inverse latex (IL.sub.5): 2.5% Fragrance: 0.3% Sepicide™ HB: 0.8% Sodium hydroxide: q.s. pH=5

Example IV-9

Care Cream

(39) Cyclomethicone: 10% Self-invertible inverse latex (IL.sub.4): 2.8% Montanov™ 202: 4.5% Preservative: 0.65% Lysine: 0.025% EDTA (disodium salt): 0.05% Xanthan gum: 0.2% Glycerol: 3% Water: q.s. for 100%

Example IV-10

Antisun Cream

(40) Simulsol™ 165: 3% Montanov™ 68: 2% C12-C15 benzoate: 8% Pecosil™ PS 100: 2% Dimethicone: 2% Cyclomethicone: 5% Octyl para-methoxycinnamate: 6% Benzophenone-3: 4% Titanium oxide: 8% Xanthan gum: 0.2% Butylene glycol: 5% Demineralized water: q.s. for 100% Self-invertible inverse latex (IL.sub.2): 1.5% Preservative, fragrance: q.s.

Example IV-11

Antisun and Self-Tanning Gel

(41) Montanov™ 68: 3.0% Glyceryl triheptanoate: 10.0% Deepaline™ PVB: 1.05% Self-invertible inverse latex (IL.sub.2): 2.2% Water: q.s. 100% Dihydroxyacetone: 5% Fragrance: 0.1% Sepicide™ HB: 0.3% 30 Sepicide™ CI: 0.1% Parsol™ MCX: 4.0%

(42) The definitions of the products used in the examples are as follows: Micropearl™ M 100 is an ultrafine powder which is very soft to the touch and which has a mattifying action, sold by Matsumo. Sepicide™ CI, imidazolidinyl urea, is a preservative sold by Seppic. Simulsol™ 165 is self-emulsifying glycerol stearate, sold by Seppic. Sepicide™ HB, a mixture of phenoxyethanol, methylparaben, ethylparaben, propylparaben and butylparaben, is a preservative sold by Seppic. Parsol™ MCX is octyl para-methoxycinnamate, sold by Givaudan. Lanol™ 37T is glycerol triheptanoate, sold by Seppic. Solagum™ L is a carrageenan, sold by Seppic. Eusolex™ 4360 is a sunscreen, sold by Merck. Deepaline™ PVB is an acylated wheat protein hydrolyzate, sold by Seppic. Primol™ 352 is a mineral oil, sold by Exxon. Pecosil™ PS 100 is Dimethicone PEG-7, sold by Phoenix. Montanov™ 68 (INCI name: cetearyl alcohol (and) cetearyl glucoside) is an emulsifying agent, sold by Seppic. Montanov™ L (INCI name: C14-22 alcohols (and) C12-20 alkyl glucoside) is an emulsifying agent, sold by Seppic. Montanov™ 202 (INCI name: arachidyl alcohol & behenyl alcohol & arachidyl) is an emulsifying agent, sold by Seppic.