Oil-in-water emulsions enriched with salt which are highly viscous and stable over time

Abstract

Disclosed is a composition in the form of an oil-in-water emulsion, including: 5-55 wt % of an oil phase; 0.025-3.75 wt % of at least one cross-linked anionic polyelectrolyte resulting from the polymerization of partially or completely salified 2-methyl 2-[(1-oxo 2-propenyl) amino] 1-propanesulfonic acid, with at least one neutral monomer selected from acrylamide, (2-hydroxy ethyl) acrylate, and N,N-dialkyl arylamides. Each alkyl group includes 1-4 carbon atoms, and at least one monomer, where R is an alkyl radical including 8-20 carbon atoms and n is a number no smaller than one and no larger than twenty, in the presence of a cross-linking agent; 0.025-3.75 wt % of a galactomannan having a degree of substitution of approximately 1/3; 37.5-94.95 wt % of a cosmetically acceptable aqueous phase, the aqueous phase including 1-25 wt % of a salt, the weight ratio between the galactomannan and the cross-linked anionic polyelectrolyte being 1:3 to 3:1.

Claims

1. A composition (C.sub.1) presented in the form of an oil-in-water type emulsion, comprising: from 5 to 55% by weight of an oil phase (P.sub.1) comprising at least one oil and optionally at least one wax; from 0.025% to 3.75% by weight of at least one cross-linked anionic polyelectrolyte (PA), the PA resulting from polymerisation of partially or completely salified 2-methyl 2-[(1-oxo 2-propenyl) amino] 1-propane sulfonic acid with at least one neutral monomer selected from the group consisting of: acrylamide, (2-hydroxy ethyl) acrylate, N,N-dialkyl acrylamide, wherein each of the alkyl groups comprises between one and four carbon atoms, and at least one monomer of formula (I): ##STR00004## wherein R represents a linear or branched alkyl radical comprising from eight to twenty carbon atoms and n represents a number greater than or equal to one and less than or equal to twenty, in the presence of at least one cross-linking agent; from 0.025% to 3.75% by weight of at least one galactomannan (GM) having a degree of substitution (DS) of approximately 1/3; and from 37.5% to 94.95% by weight of a cosmetically acceptable aqueous phase (P.sub.2), said aqueous phase (P.sub.2) comprising from 1% to 25% by weight of at least one salt (S) presented in a dissolved form, wherein for said composition (C.sub.1), the weight ratio between the at least one galactomannan (GM) and the cross-linked anionic polyelectrolyte (PA) is greater than or equal to 1/3 and less than or equal to 3/1.

2. The composition (C.sub.1) of claim 1, wherein said cross-linked anionic polyelectrolyte (PA) comprises: from 20% molar to 80% molar of monomeric units from said partially or completely salified 2-methyl-2-[(1-oxo-2-propenyl) amino] 1-propane sulfonic acid; from 15% molar to 75% molar of monomeric units from said neutral monomer; and from 0.5% to 5% molar of monomeric units from said monomer of formula (I).

3. The composition (C.sub.1) of claim 1, wherein said neutral monomer is acrylamide, (2-hydroxy ethyl) acrylate or N,N-dimethyl acrylamide.

4. The composition (C.sub.1) of claim 1, wherein said monomer of formula (I) is tetraethoxylated lauryl methacrylate.

5. The composition (C.sub.1) of claim 1, wherein said cross-linked anionic polyelectrolyte (PA) is a terpolymer of partially salified 2-methyl 2-[(1-oxo-2-propenyl) amino] 1-propane sulfonic acid in the form of ammonium salt, N,N-dimethyl acrylamide and tetraethoxylated lauryl methacrylate, cross-linked with trimethylol propanetriacrylate.

6. The composition (C.sub.1) of claim 1, wherein said cross-linked anionic polyelectrolyte (PA) is a terpolymer of partially salified 2-methyl 2-[(1-oxo 2-propenyl) amino] 1-propane sulfonic acid in the form of ammonium salt, (2-hydroxy ethyl) acrylate and tetraethoxylated lauryl methacrylate, cross-linked with trimethylol propanetriacrylate.

7. The composition (C.sub.1) of claim 1, wherein the salt (S) is an inorganic salt consisting of a cation that is an ammonium ion or a metal cation and of an anion selected from the elements of the group consisting of the halides, carbonates, bicarbonates, phosphates, nitrates, borates and sulfates.

8. The composition (C.sub.1) of claim 1, wherein the salt (S) is an organic salt consisting of a cation that is an ammonium ion and of a metal cation and an organic anion that is an organic compound having at least one carboxylic acid function in carboxylate form or at least one sulfonic acid function in sulfonate form or at least one sulfate function.

9. The composition (C.sub.1) of claim 1, wherein the salt (S) is an organic salt selected from the group consisting of sodium glycolate, sodium citrate, sodium salicylate, sodium lactate, sodium gluconate, zinc gluconate, manganese gluconate, copper gluconate and magnesium aspartate.

10. The composition (C.sub.1) of claim 1, wherein the salt (S) is an organic salt selected from the group consisting of sodium 2-phenylbenzimidazole-5-sulfonate and sodium 4-hydroxy 2-methoxy 5-(oxo-phenylmethyl)benzene sulfonate.

11. The composition (C.sub.1) of claim 1, wherein the dynamic viscosity thereof measured at a temperature of 20 C., by means of a Brookfield type viscometer, is greater than or equal to 30,000 mPa.Math.s and less than or equal to 200,000 mPa.Math.s.

12. A method for preparing the composition (C.sub.1) of claim 1, comprising: at least one step a) for preparing a phase (P.sub.1) by mixing the cross-linked anionic polyelectrolyte (PA) and galactomannan (GM) in the oil phase (P.sub.1); and at least one step b) for emulsifying said phase (P.sub.1) obtained following step a) with a cosmetically acceptable aqueous phase (P.sub.2).

13. The composition (C.sub.1) of claim 2, wherein said neutral monomer is chosen from acrylamide, (2-hydroxy ethyl) acrylate or N,N-dimethyl acrylamide.

14. The composition (C.sub.1) of claim 2, wherein said monomer of formula (I) is tetraethoxylated lauryl methacrylate.

15. The composition (C.sub.1) of claim 3, wherein said monomer of formula (I) is tetraethoxylated lauryl methacrylate.

16. The composition (C.sub.1) of claim 2, wherein said cross-linked anionic polyelectrolyte (PA) is a terpolymer of partially salified 2-methyl 2-[(1-oxo 2-propenyl) amino] 1-propane sulfonic acid in the form of ammonium salt, N,N-dimethyl acrylamide and tetraethoxylated lauryl methacrylate, cross-linked with trimethylol propanetriacrylate.

17. The composition (C.sub.1) of claim 3, wherein said cross-linked anionic polyelectrolyte (PA) is a terpolymer of partially salified 2-methyl 2-[(1-oxo 2-propenyl) amino] 1-propane sulfonic acid in the form of ammonium salt, N,N-dimethyl acrylamide and tetraethoxylated lauryl methacrylate, cross-linked with trimethylol propanetriacrylate.

18. The composition (C.sub.1) of claim 4, wherein said cross-linked anionic polyelectrolyte (PA) is a terpolymer of partially salified 2-methyl 2-[(1-oxo 2-propenyl) amino] 1-propane sulfonic acid in the form of ammonium salt, N,N-dimethyl acrylamide and tetraethoxylated lauryl methacrylate, cross-linked with trimethylol propanetriacrylate.

19. The composition (C.sub.1) of claim 2, wherein said cross-linked anionic polyelectrolyte (PA) is a terpolymer of partially salified 2-methyl 2-[(1-oxo 2-propenyl) amino] 1-propane sulfonic acid in the form of ammonium salt, (2-hydroxy ethyl) acrylate and tetraethoxylated lauryl methacrylate, cross-linked with trimethylol propanetriacrylate.

Description

(1) The experimental report hereinafter illustrates the invention, without limiting the invention.

1.1 Preparation of a Terpolymer of Ammonium 2-methyl 2-[(1-oxo 2-propenyl)amino]1-propane sulfonate, NN-dimethyl acrylamide and Tetraoxylated Lauryl Methacrylate [AMPSNH4/DMAM/MAL(4OE) 77.4/19.2/3.4 Molar], Cross-Linked with Trimethylol Panetriacrylate (TMPTA) [Example According to the Invention]

(2) 592 g of an aqueous solution containing 15% by weight of ammonium 2-methyl 2-[(1-oxo 2-propenyl)amino]1-propane sulfonate (AMPSNH.sub.4) in a tert-butanol/water mixture (97.5/2.5 by volume), 10.1 g of NN-dimethyl acrylamide (DMAM), 4.2 g of tetraethoxylated lauryl methacrylate [MAL(4OE)] and 0.75 g of TMPTA are loaded into a reactor maintained at 25 C. under stirring.

(3) After sufficient time to achieve satisfactory homogenisation of the solution, the solution is deoxygenated by bubbling nitrogen heated to 70 C. 0.42 g of dilauroyl peroxide is then added and the reaction medium is then maintained for approximately 60 minutes at 70 C. and 2 hours at 80 C.

(4) After cooling, the powder that formed during polymerisation is filtered and dried to obtain the required product, hereinafter referred to as: Polyelectrolyte PA.sub.1.

1-2: Preparation of a Terpolymer of Ammonium 2-methyl 2-[(1-oxo 2-propenyl)amino]1-propane sulfonate, (2-hydroxy ethyl) acrylate and Tetraoxylated Lauryl Methacrylate [AMPSNH4/HEA/MAL(4OE) 77.4/19.2/3.4 Molar], Cross-Linked with (TMPTA) [Example According to the Invention]

(5) Using the operating conditions of the method described in paragraph 1.1 above, the quantity required by weight of an aqueous solution containing 15% by weight of AMPSNH.sub.4 in a tert-butanol/water mixture (97.5/2.5 by volume) so as to introduce 77.4 molar equivalents of AMPSNH.sub.4, the quantity required by weight of (2-hydroxy ethyl) acrylate (HEA) so as to introduce 19.2 molar equivalents of HEA, the quantity required by weight of [MAL(4OE) so as to introduce 3.4 molar equivalents of [MAL(4OE)], and the quantity required by weight of TMPTA so as to obtain the same molar proportion of TMPTA as in paragraph 1-1 are loaded into a reactor maintained at 25 C. under stirring.

(6) After sufficient time to achieve satisfactory homogenisation of the solution, the solution is deoxygenated by bubbling nitrogen heated to 70 C. 0.42 g of dilauroyl peroxide is then added and the reaction medium is then maintained for approximately 60 minutes at 70 C. and 2 hours at 80 C.

(7) After cooling, the powder that formed during polymerisation, is filtered and dried to obtain the required product, hereinafter referred to as: Polyelectrolyte PA.sub.2.

1-3: Preparation of a Copolymer of Ammonium 2-methyl 2-[(1-oxo 2-propenyl)amino]1-propane sulfonate and Tetraoxylated Lauryl Methacrylate [AMPS/MAL(4OE) 95/5 Molar], Cross-Linked with TMPTA [Comparative Example]

(8) Using the operating conditions of the method described in paragraph 1.1 above, the quantity required by weight of an aqueous solution containing 15% by weight of AMPSNH.sub.4 in a tert-butanol/water mixture (97.5/2.5 by volume) so as to introduce 95 molar equivalents of AMPSNH.sub.4, the quantity required by weight of [MAL(4OE)] so as to introduce 5 molar equivalents of [MAL(4OE)], and the quantity required by weight of TMPTA so as to obtain the same molar proportion of TMPTA as in paragraph 1-1 are loaded into a reactor maintained at 25 C. under stirring.

(9) After a sufficient time to achieve satisfactory homogenisation of the solution, the solution is deoxygenated by bubbling nitrogen heated to 70 C. 0.42 g of dilauroyl peroxide is then added and the reaction medium is then maintained for approximately 60 minutes at 70 C. and 2 hours at 80 C.

(10) After cooling, the powder that formed during polymerisation, is filtered and dried to obtain the required product, hereinafter referred to as: Polyelectrolyte PA.sub.3.

1-4: Preparation of a Copolymer of 2-methyl 2-[(1-oxo 2-propenyl)amino]1-propane sulfonate and (2-hydroxy ethyl) acrylate [AMPS/HEA 90/10 Molar], Cross-Linked with TMPTA [Comparative Example]

(11) Using the operating conditions of the method described in paragraph 1.1 above, the quantity required by weight of an aqueous solution containing 15% by weight of AMPSNH.sub.4 in a tert-butanol/water mixture (97.5/2.5 by volume) so as to introduce 90 molar equivalents of AMPSNH.sub.4, the quantity required by weight of HEA so as to introduce 10 molar equivalents of HEA, and the quantity required by weight of TMPTA so as to obtain the same molar proportion of TMPTA as in paragraph 1-1 are loaded into a reactor maintained at 25 C. under stirring.

(12) After a sufficient time to achieve satisfactory homogenisation of the solution, the solution is deoxygenated by bubbling nitrogen heated to 70 C. 0.42 g of dilauroyl peroxide is then added and the reaction medium is then maintained for approximately 60 minutes at 70 C. and 2 hours at 80 C.

(13) After cooling, the powder that formed during polymerisation is filtered and dried to obtain the required product, hereinafter referred to as: Polyelectrolyte PA.sub.4.

2-1: Preparation of Oil-in-Water Emulsions According to the Invention

(14) Thirteen oil-in-water emulsions according to the invention, referenced (E.sub.1) to (E.sub.13), of which the proportions by weight of the constituents thereof are recorded in table 1 below, are prepared using the following method: in a first beaker, at a temperature of 20 C., one of the polyelectrolytes PA.sub.1 or PA.sub.2 and Tara gum are dispersed progressively and successively in an oil phase under mechanical stirring at 80 revolutions per minute; in a second beaker, at a temperature of 20 C., the aqueous phase comprising the water and the quantity by weight of salt required is prepared; the content of the first beaker is progressively poured into the second beaker at a temperature of 20 C., under mechanical stirring by means of a deflocculator at 1200 revolutions per minute; the mixture obtained is maintained under stirring for 10 minutes, then drained to obtain the oil-in-water emulsions (E.sub.1) to (E.sub.13).

(15) TABLE-US-00001 TABLE 1 Emulsion (E.sub.1) (E.sub.2) (E.sub.3) (E.sub.4) (E.sub.5) (E.sub.6) Oil phase: C8-C10 15% 15% 15% 15% 15% .sup.15% Triglycerides Stabilising system: Polyelectrolyte 1% 1% 1% 1% 1% 1.25% (PA.sub.1) Tara gum .sup.(2) 1% 1% 1% 1% 1% 0.75% Aqueous phase: Water Qs Qs Qs Qs Qs Qs 100% 100% 100% 100% 100% 100% Sodium 2% 4% 6% 8% 10% 2% chloride Geogard 0.6%.sup. 0.6%.sup. 0.6%.sup. 0.6%.sup. 0.6% 0.6% 221.sup.(1) Emulsion (E.sub.7) (E.sub.8) (E.sub.9) (E.sub.10) (E.sub.11) Oil phase: C8-C10 .sup.15% .sup.15% 15% 15% 15% Triglycerides Stabilising system: Polyelectrolyte 1.25% 1.25% 0.5% 0.5% 0.5% (PA.sub.1) Tara gum .sup.(2) 0.75% 0.75% 1.50% 1.50% 1.50% Aqueous phase: Water Qs Qs Qs Qs Qs 100% 100% 100% 100% 100% Sodium 4% .sup.10% .sup.4% 10% .sup.4% chloride Geogard 0.6% 0.6% 0.6% 0.6% 0.6% 221.sup.(1) Emulsion (E.sub.12) (E.sub.13) Oil phase: C8-C10 15% 15% Triglycerides Stabilising system: Polyelectrolyte 1% 1% (PA.sub.1) Tara gum .sup.(2) 1% 1% Aqueous phase: Water Qs Qs 100% 100% Sodium chloride 2% 10% Geogard 221.sup.(1) 0.6%.sup. 0.6% .sup.(1)Geogard 221 is a mixture of dehydroacetic acid and benzyl alcohol used as a preservative and marketed by the company LONZA. .sup.(2) Tara gum (CAS number: 39300-88-4) is marketed under the name Tara gum by the company Starlight.

2-2: Preparation of Oil-in-Water Emulsions According to the Prior Art

(16) Ten oil-in-water emulsions, referenced (F.sub.1) to (F.sub.10), of which the proportions by weight of the constituents thereof are recorded in table 2 below, are prepared using the following method: in a first beaker, at a temperature of 20 C., one of the polyelectrolytes PA.sub.1 or PA.sub.2 and Tara gum are dispersed progressively and successively in an oil phase under mechanical stirring at 80 revolutions per minute; in a second beaker, at a temperature of 20 C., the aqueous phase comprising the water and the quantity by weight of salt required is prepared; the content of the first beaker is progressively poured into the second beaker at a temperature of 20 C., under mechanical stirring by means of a deflocculator at 1200 revolutions per minute; the mixture obtained is maintained under stirring for 10 minutes, then drained to obtain the oil-in-water emulsions (F.sub.1) to (F.sub.10).

(17) TABLE-US-00002 TABLE 2 Emulsion (F.sub.1) (F.sub.2) (F.sub.3) (F.sub.4) (F.sub.5) Oil phase: C8-C10 15% 15% 15% 15% 15% Triglycerides Stabilising system: Polyelectrolyte 1% 2% 2% 0% 1.25% (PA.sub.1) Tara gum 1% 0% 0% 2% 0.75% Aqueous phase: Water Qs Qs Qs Qs Qs 100% 100% 100% 100% 100% Sodium chloride 0% 2% 4% 4% 0% Geogard 221 0.6% 0.6% 0.6% 0.6% 0.6% Emulsion (F.sub.6) (F.sub.7) (F.sub.8) (F.sub.9) (F.sub.10) Oil phase: C8-C10 15% 15% 15% 15% 15% Triglycerides Stabilising system: Polyelectrolyte 0.5% 0% 0% 0% 0% (PA.sub.1) Polyelectrolyte 0% 1% 1% 0% 0% (PA.sub.3) Polyelectrolyte 0% 0% 0% 1% 1% (PA.sub.4) Tara gum 1.50% 1% 1% 1% 1% Aqueous phase: Water Qs Qs Qs Qs Qs 100% 100% 100% 100% 100% Sodium chloride 0% 2% 10% 2% 10% Geogard 221.sup.(1) 0.6% 0.6% 0.6% 0.6% 0.6%

2-3: Demonstration of the Properties and Characteristics of the Oil-in-Water Emulsions According to the Invention Compared to Oil-in-Water Emulsions According to the Prior Art

(18) The oil-in-water emulsions (E.sub.1) to (E.sub.13) according to the invention and the oil-in-water emulsions (F.sub.1) to (F.sub.10) according to the prior art prepared in this way, are then stored in an insulated climatic chamber regulated at a temperature of 20 C. for 7 days. After this 7-day period and for each oil-in-water emulsion: the visual appearance is observed, the dynamic viscosity () of each emulsion is measured at 20 C., by means of a Brookfield LVT type viscometer at a speed of 6 revolutions per minute (V6) when said dynamic viscosity is less than equal to approximately 100,000 mPa.Math.s, equipped with a suitable mobile assembly or by means of a Brookfield RVT type viscometer at a speed of 5 revolutions per minute when said dynamic viscosity is greater than 100,000 mPa.Math.s, equipped with a suitable mobile assembly. The conductivity at 20 C. is measured by means of an LF 196 conductimeter by the company WTW equipped with a Tetracon 96 electrode.

(19) The oil-in-water emulsions are then replaced and stored in the same insulated climatic chamber regulated at a temperature of 20 C. for up to three months. After a period of months, each emulsion is removed from the climatic chamber to observe the appearance thereof. The results obtained for the oil-in-water emulsions (E1) to (E13) according to the invention are recorded in table 3 below and the results obtained for the comparative oil-in-water emulsions (F.sub.1) to (F.sub.10) are recorded in table 4 hereinafter.

(20) TABLE-US-00003 TABLE 3 Emulsion (E.sub.1) (E.sub.2) (E.sub.3) (E.sub.4) (E.sub.5) (E.sub.6) E.sub.7) Visual appearance ++ ++ ++ ++ ++ ++ ++ after 7 days at 20 C. Viscosity (Brookfield 83,000 75,000 78,000 71,000 82,000 86,000 62,500 LVT, V6) in mPas. Conductivity in 32.6 54.8 76.6 96.5 116.5 31.8 55.0 mS .Math. cm.sup.1 Visual appearance ++ ++ ++ ++ ++ ++ ++ after 3 months at 20 C. Emulsion (E.sub.8) (E.sub.9) (E.sub.10) (E.sub.11) (E.sub.12) (E.sub.13) Visual appearance ++ ++ ++ ++ ++ ++ after 7 days at 20 C. Viscosity (Brookfield 68,000 95,000 124,000* 54,000 84,000 90,000 LVT, V6) in mPas. Conductivity in 113.9 55.1 113.4 56.5 32.3 120.4 mS .Math. cm.sup.1 Visual appearance ++ ++ ++ ++ ++ ++ after 3 months at 20 C. ++: Homogeneous and smooth appearance *dynamic viscosity measured at 20 C. with the Brookfield RVT viscometer, speed 5 revolutions per minute

(21) TABLE-US-00004 TABLE 4 Emulsion (F.sub.1) (F.sub.2) (F.sub.3) (F.sub.4) (F.sub.5) Visual () () () () () appearance after 7 days at 20 C. Viscosity 175,000* 72,500 55,000 47,000 133,000* (Brookfield LVT, V6) in mPas. Conductivity 1.4 31.6 57.0 55.4 1.7 in mS .Math. cm.sup.1 Visual () () () () () appearance after 3 months at 20 C. Emulsion (F6) (F7) (F8) (F9) (F10) Visual () () () () () appearance after 7 days at 20 C. Viscosity 142,000* 33,000 41,000 31,000 40,000 (Brookfield LVT, V6) in mPas. Conductivity 0.7 31.4 120.7 31.5 120.6 in mS .Math. cm.sup.1 Visual () () () () () appearance after 3 months at 20 C. *dynamic viscosity measured at 20 C. with the Brookfield RVT viscometer, speed 5 revolutions per minute. (): Presence of lumps and clusters (): Heterogeneous appearance with presence of lumps and clusters

2-4: Analysis of the Results

(22) The results are deemed to be satisfactory when the visual appearance of an oil-in-water emulsion is deemed to be homogenous and smooth after a storage period of three months at 20 C. of said oil-in-water emulsion, and when the dynamic viscosity thereof measured at 20 C., by means of a Brookfield LVT type viscometer at a speed of 6 revolutions per minute, equipped with the suitable mobile assembly, is greater than or equal to 30,000 mPa.Math.s.

(23) The emulsions (E.sub.1) to (E.sub.13) according to the invention have a smooth appearance, devoid of lumps and clusters, even following a prolonged storage period of 3 months at 20 C.

(24) On the other hand, the results obtained with the emulsions (F.sub.2) and (F.sub.3) show that, when the stabilising system of the oil-in-water emulsion consists solely of the polyelectrolyte (PA.sub.1) in the presence of a quantity of 2% and 4% of sodium chloride, oil-in-water emulsions having a homogeneous and smooth appearance after a storage period of 7 days at 20 C. are not obtained.

(25) In addition, the results obtained with the emulsion (F.sub.4) show that when the stabilising system of the oil-in-water emulsions solely consists of Tara gum in the presence of 4% NaCl, oil-in-water emulsions having a homogeneous and smooth appearance after a storage period of 7 days at 20 C. are not obtained.

(26) For tara gum to polyelectrolyte (PA.sub.1) ratios by weight respectively equal to 1/1, 3/5 and 3/1 and in the absence of sodium chloride, the results obtained with the emulsions (F.sub.1), (F.sub.5) and (F.sub.8) show that oil-in-water emulsions having a homogeneous and smooth appearance after a storage period of 7 days at 20 C. are not obtained.

(27) The results obtained with the emulsions (F.sub.7) and (F.sub.8), (F.sub.9) and (F.sub.10) comprising respectively 2% by weight and 4% by weight of sodium chloride show that when the stabilising system consists of Tara gum and one of the polyelectrolytes (PA.sub.3) or (PA.sub.4), oil-in-water emulsions having a homogeneous and smooth appearance after a storage period of 7 days at 20 C. are not obtained.

(28) The comparison of the results obtained with the oil-in-water emulsions (E.sub.1) to (E.sub.13) according to the invention with those obtained with the oil-in-water emulsions (F.sub.1) to (F.sub.6) according to the prior art, allow an improvement in the appearance of the salt-enriched oil-in-water emulsions to be shown, while retaining a high degree of viscosity, representing an additional technical effect induced by the invention according to the present patent application.

3-1: Preparation of Oil-in-Water Emulsions According to the Prior Art

(29) Two oil-in-water emulsions, referenced (F.sub.11) to (F.sub.12), of which the proportions by weight of the constituents thereof are recorded in table 5 below, are prepared using the following method: in a first beaker, at a temperature of 20 C., the polyelectrolyte PA.sub.1 and Xanthan gum are dispersed progressively and successively in an oil phase under mechanical stirring at 80 revolutions per minute; in a second beaker, at a temperature of 20 C., the aqueous phase comprising the water and the quantity by weight of salt required is prepared; the content of the first beaker is progressively poured into the second beaker at a temperature of 20 C., under mechanical stirring using a deflocculator at 1200 revolutions per minute; the mixture obtained is maintained under stirring for 10 minutes, then drained to obtain the oil-in-water emulsions (F.sub.11) to (F.sub.12).

(30) TABLE-US-00005 TABLE 5 Emulsion (F.sub.11) (F.sub.12) Oil phase: C8-C10 15% 15% Triglycerides Stabilising system: Polyelectrolyte 1% 1% (PA.sub.1) Keltrol CG-T.sup.(3) 1% 1% Aqueous phase: Water Qs 100% Qs 100% Sodium chloride 2% 10% Geogard 221 0.6% 0.6% .sup.(3)Keltrol CG-T is xanthan gum marketed by the company CP Kelco

3-2: Preparation of Oil-in-Water Emulsions of the Remodelling Rinse-Off Cream Mask Type for Stressed and Weakened Hair According to the Invention and According to the Prior Art

(31) One oil-in-water emulsion according to the prior art referenced (F.sub.13) and one oil-in-water emulsion according to the invention referenced (E.sub.14), of which the proportions by weight of the constituents thereof are recorded in table 1 below, are prepared using the following method: in a first beaker, an oil phase is prepared by successively introducing Lanol P, Lanol 99, jojoba oil and Montanov 82 at a temperature of 80 C., and then the polyelectrolyte PA.sub.1 is successively dispersed, then Tara gum or xanthan gum under mechanical stirring at 80 revolutions per minute; in a second beaker, at a temperature of 20 C., the aqueous phase comprising water, whereon butylene glycol, N-cocoyl amino acids, PECOSIL SPP 50, AMONYL DM, SEPICIDE HB and SEPICIDE CI are poured progressively and successively, is prepared; the content of the first beaker is progressively poured into the second beaker at a temperature of 20 C., under mechanical stirring using a deflocculator at 1200 revolutions per minute; the mixture obtained is maintained under stirring for 10 minutes, then drained to obtain the oil-in-water emulsions (F.sub.13) and (E.sub.14).

(32) TABLE-US-00006 TABLE 6 Emulsion (F.sub.13) (E.sub.14) Oil phase: Jojoba oil 1% 1% LanolP.sup.(4) 6% 6% Lanol99.sup.(5) 5% 5% Montanov82.sup.(6) 3% 3% Stabilising system: Polyelectrolyte 1% 1% (PA1) Keltrol CG-T.sup.(3) 1% 0% Tara gum.sup.(2) 0% 1% Aqueous phase: Water Qs. 100% Qs. 100% Butylene Glycol 3% 3% N-cocoyl amino 0.7% 0.7% acids PECOSILSPP 0.75% 0.75% 50.sup.(7) AMONYLDM.sup.(8) 1% 1% SEPICIDEHB.sup.(9) 0.3% 0.3% SEPICIDECI.sup.(12) 0.2% 0.2% .sup.(4)LANOL P is a glycol palmitate used as an additive with a stabilising effect, and marketed by the company SEPPIC. .sup.(5)LANOL 99 is isononyl isononanoate marketed by the company SEPPIC. .sup.(6)MONTANOV 82 is an emulsifying agent based on cetearyl alcohol and cocoylglucoside. .sup.(7)PECOSIL SPP 50 is a potassium dimethicone PEG-7 panthenyl phosphate, marketed by the company PHOENIX. .sup.(8)AMONYL DM is a cationic surfactant presented in the form of a quaternary ammonium salt, the INCI name of which is Polyquaternium 82, and marketed by the company SEPPIC. .sup.(9)SEPICIDE HB, which is a mixture of phenoxyethanol, methylparaben, ethylparaben and butylparaben, is a preservative marketed by the company SEPPIC. (10): SEPICIDE CI, imidazoline urea, is a preservative marketed by the company SEPPIC.

3-3: Demonstration of the Properties and Characteristics of the Oil-in-Water Emulsions According to the Invention Compared to Oil-in-Water Emulsions According to the Prior Art

(33) The oil-in-water emulsions (F.sub.11), (F.sub.12) and (F.sub.13) according to the prior art and the emulsion (E.sub.14) according to the invention are evaluated according to the experimental protocol described in paragraph 2-3 above.

(34) The results obtained with the oil-in-water emulsions (F.sub.11), (F.sub.12) and (F.sub.13) according to the prior art and the results obtained with the emulsions (E.sub.14) according to the invention are recorded in table 7 below.

(35) TABLE-US-00007 TABLE 7 Emulsion (F.sub.11) (F.sub.12) (F.sub.13) (E.sub.14) Visual appearance after () () () (++) 7 days at 20 C. Viscosity (Brookfield 56,500 52,000 300,000* 305,000* LVT, V6) in mPas. Conductivity in 32.8 120.6 3.7 3.5 mS .Math. cm.sup.1 Visual appearance after () () () (++) 3 months at 20 C. (++): Homogeneous and smooth appearance (): Presence of lumps and clusters (): Heterogeneous appearance with presence of lumps and clusters *dynamic viscosity measured at 20 C. with the Brookfield RVT viscometer, speed 5 revolutions per minute.

(36) 3-4: Analysis of the Results

(37) The results are deemed to be satisfactory when the visual appearance of an oil-in-water emulsion is deemed to be homogenous and smooth after a storage period of three months at 20 C. of said oil-in-water emulsion, and when the dynamic viscosity thereof measured at 20 C., by means of a Brookfield LVT type viscometer at a speed of 6 revolutions per minute, equipped with the suitable mobile assembly, is greater than or equal to 30,000 mPa.Math.s.

(38) The emulsions (F.sub.11) and (F.sub.12) according to the prior art should be compared respectively to the emulsions (E.sub.1) and (E.sub.5) according to the invention as they only differ in the compositions thereof by the use of xanthan gum instead of Tara gum in the stabilising system. The emulsions (E.sub.1) and (E.sub.5) have a smooth appearance, devoid of lumps and clusters, following a prolonged storage period of 3 months at 20 C., whereas the emulsions (F.sub.11) and (F.sub.12) exhibit a heterogeneous appearance with the presence of lumps and clusters after the same storage period under the same operating conditions.

(39) Similarly, the oil-in-water emulsion (E.sub.14) according to the invention has a smooth appearance, devoid of lumps and clusters, following a prolonged storage period of 3 months at 20 C., whereas the emulsion (F.sub.13) according to the prior art exhibits a heterogeneous appearance with the presence of lumps and clusters after the same storage period under the same operating conditions.

(40) The comparison of the results obtained with the oil-in-water emulsions (E.sub.1), (E.sub.5) and (E.sub.14) according to the invention with those obtained with the oil-in-water emulsions (F.sub.11), (F.sub.12) and (F.sub.13) according to the prior art, also enable an improvement in the appearance of the salt-enriched oil-in-water emulsions to be demonstrated, while retaining a high degree of viscosity, representing an additional technical effect induced by the invention according to the present patent application.

Example of Illustrative Formulas

4-1: Body Moisturising Treatment Cream Gel

(41) Formula:

(42) TABLE-US-00008 A Jojoba oil 14.10% C12-C15 Alkyl Benzoate 6.7% DC 25 4.2% DL alpha Tocopherol 0.05% B Maris Aqua 70.85% AQUAXYL 3% C Polyelectrolyte (PA.sub.1) 2% Tara gum.sup.(2) 1% D Euxyl PE9010 1% Fragrance 0.1%
Operating Method:

(43) Mix the constituents of the oil phase A at a temperature of 80 C. under stirring. Then successively add the ingredients of phase C.

(44) Prepare the aqueous phase B and heat it to 80 C. under stirring.

(45) Add the aqueous phase B progressively to the mixture of phases A+C and emulsify by means of a stirrer equipped with a Silverson rotor-stator mobile assembly.

(46) Then cool to 25 C., then add phase D.

(47) Appearance after 1 day at 20 C.: homogeneous compact cream.

(48) Dynamic viscosity after 1 day at 20 C.: 117,000 mPa.Math.s (Brookfield RVT, M7, V5)

(49) Appearance after 7 days at 20 C.: homogeneous compact cream.

(50) Dynamic viscosity after 7 days at 20 C.: 105,000 mPa.Math.s (Brookfield RVT, M7, V5)

(51) Appearance after 1 month at 20 C.: homogeneous compact cream.

(52) Dynamic viscosity after 1 month at 20 C.: 110,000 mPa.Math.s (Brookfield RVT, M7, V5).

4-2: Face Mask Cream Gel

(53) Formula:

(54) TABLE-US-00009 A Triglycerides 4555 (C8C10) 9% C12-C15 Alkyl Benzoate 4% Isohexadecane 2% DL alpha Tocopherol 0.10% B Maris Aqua qsp 100% C Polyelectrolyte (PA.sub.1) 1.3% Tara gum.sup.(2) 0.7% D Euxyl PE9010 1% Fragrance 0.1%
Operating Method:

(55) Mix the constituents of the oil phase A at a temperature of 80 C. under stirring. Then successively add the ingredients of phase C.

(56) Prepare aqueous phase B and heat it to 80 C. under stirring.

(57) Add aqueous phase B progressively to the mixture of phases A+C then emulsify by means of a stirrer equipped with a Silverson rotor-stator mobile assembly.

(58) Then cool to 25 C. and add phase D.

(59) Appearance after 1 day at 20 C.: Homogeneous compact cream.

(60) Dynamic viscosity after 1 day at 20 C.: 71,000 mPa.Math.s (Brookfield LVT, M4 V6)

(61) Appearance after 7 days at 20 C.: Homogeneous compact cream.

(62) Dynamic viscosity after 7 days at 20 C.: 78,400 mPa.Math.s (Brookfield LVT, M4 V6)

(63) Appearance after 1 month at 20 C.: Homogeneous compact cream.

(64) Dynamic viscosity after 1 month at 20 C.: 79,100 mPa.Math.s (Brookfield LVT, M4 V6).

4-3: Body Cream

(65) Formula:

(66) TABLE-US-00010 Triglycerides 4555 (C8C10) 12% C12-C15 Alkyl Benzoate 5.3% Isohexadecane 2.7% Cetyl alcohol 2% DL alpha Tocopherol 0.10% Polyelectrolyte (PA.sub.1) 1.5% Tara gum.sup.(2) 0.5% Water qsp 100% Givobio GZn 1% Sepicalm S 3% Euxyl PE9010 1% Fragrance 0.1%

4-4: Organomineral Sun Spray

(67) Formula:

(68) TABLE-US-00011 A Isodecyl neopentanoate 20% Cyclodimethicone 5% Ethylhexylmethoxicinnamate 6% Butyl Methoxydibenzoylmethane 3% DL alpha Tocopherol 0.05% B Water Qs. 100% Tetrasodium EDTA 0.2% Glycerin 7% Phenyl benzimidazole sulfonic acid 3% (salified with necessary molar quantity of soda) C Polyelectrolyte (PA.sub.1) 1.3% Tara gum.sup.(2) 0.7% D SEPICIDE HB 1% Fragrance 0.1%
AQUAXYL (INCI name: Xylitylglucoside & Anhydroxylitol & Xylitol): Moisturising composition marketed by the company SEPPIC.
Euxyl PE9010 (INCI name: Phenoxyethanol & Ethylhexyl Glycerin): composition used as preservative.
GIVOBIO GZn (INCI name: Zinc Gluconate): composition marketed by the company SEPPIC.
LANOL 99 (INCI name: Isononyl Isononanoate): ester used as oil phase in cosmetic composition preparation and distributed by the company SEPPIC.
Maris Aqua: sea water containing 8% sodium chloride.
SEPICIDE HB (INCI name: Phenoxyethanol/Methylparaben/Ethylparaben/Propylparaben/Butylparaben): preservative containing phenoxyethanol, marketed by the company SEPPIC.
SEPICALM S: (INCI name: Sodium Cocoyl Amino acids And Sarcosine And Potassium Aspartate And Magnesium Aspartate): anti-inflammatory composition marketed by the company SEPPIC.
SERENIKS 207 (INCI name: Tsuga Canadensis Leaf Extract And Water And Butylene Glycol) is an anti-aging composition.