(19)
(11)EP 2 174 646 B1

(12)EUROPEAN PATENT SPECIFICATION

(45)Mention of the grant of the patent:
22.05.2019 Bulletin 2019/21

(21)Application number: 08790433.0

(22)Date of filing:  08.08.2008
(51)International Patent Classification (IPC): 
A61K 8/14(2006.01)
A61K 8/36(2006.01)
A61K 8/63(2006.01)
A61K 8/92(2006.01)
A61K 9/133(2006.01)
A61K 47/12(2006.01)
A61K 47/28(2006.01)
A61K 8/31(2006.01)
A61K 8/37(2006.01)
A61K 8/68(2006.01)
A61Q 19/00(2006.01)
A61K 47/06(2006.01)
A61K 47/18(2017.01)
(86)International application number:
PCT/JP2008/002176
(87)International publication number:
WO 2009/019891 (12.02.2009 Gazette  2009/07)

(54)

REVERSE VESICLE

UMGEDREHTES VESIKEL

VÉSICULE INVERSÉE


(84)Designated Contracting States:
AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MT NL NO PL PT RO SE SI SK TR

(30)Priority: 09.08.2007 JP 2007207539

(43)Date of publication of application:
14.04.2010 Bulletin 2010/15

(73)Proprietor: Kao Corporation
Chuo-Ku Tokyo 103-8210 (JP)

(72)Inventor:
  • OKUBO, Koji
    Tokyo 131-8501 (JP)

(74)Representative: Hoffmann Eitle 
Patent- und Rechtsanwälte PartmbB Arabellastraße 30
81925 München
81925 München (DE)


(56)References cited: : 
EP-A2- 0 420 722
FR-A1- 2 855 048
US-A- 5 716 639
US-A1- 2005 163 742
US-A1- 2005 287 095
EP-B1- 1 347 734
JP-A- 09 508 415
US-A1- 2005 013 839
US-A1- 2005 163 812
US-A1- 2007 104 774
  
  • KUNIEDA ET AL.: 'Formation of vesicles and microemulsions in a water/tetraethylene glycol dodecyl ether/dodecane system' LANGMUIR vol. 7, 1991, pages 1915 - 1919, XP008129207
  • NAKAMURA K. AND KUNIEDA H.: 'Normal and reverse vesicles with nonionic surfactant: solvent diffusion and permeability' LANGMUIR vol. 12, 1996, pages 3045 - 3054, XP008129208
  • KUNIEDA ET AL.: 'Formation of reversed vesicles' J. AM. CHEM. SOC. vol. 113, 1991, pages 1051 - 1052, XP000172752
  • KUNIEDA ET AL.: 'Spontaneous formation of reverse vesicles' J. PHYS. CHEM. vol. 97, 1993, pages 9525 - 9531, XP008129212
  
Note: Within nine months from the publication of the mention of the grant of the European patent, any person may give notice to the European Patent Office of opposition to the European patent granted. Notice of opposition shall be filed in a written reasoned statement. It shall not be deemed to have been filed until the opposition fee has been paid. (Art. 99(1) European Patent Convention).


Description

Field of the Invention



[0001] The present invention relates to a reverse vesicle composition.

Background of the Invention



[0002] The human stratum corneum, in which intercellular lipid forms a lamellar structure, is known to play an important role in barrier and moisturizing functions. Thus, in the production of skin agents for external application such as creams and emulsions, there is demand for a pharmaceutical product which enhances such functions and improves skin conditions.

[0003] From the viewpoint of enhancing barrier and moisturizing functions, a pharmaceutical product having the same lamellar structure as that of the skin is desired for the enhancement of skin permeability and moisturizing effect. Since the structure of a pharmaceutical product having a vesicle structure is similar to the structure of intercellular lipids in stratum corneum, such a pharmaceutical product is thought to have higher functions in terms of skin permeability, moisturizing effect.

[0004]  Hitherto, it has been known that vesicle compositions in which a continuous phase is an oily phase have been rarely employed. The only examples are a reverse vesicle formed of a nonionic surfactant, oil, and water (Non-Patent Document 1), and a water-free reverse vesicle containing sucrose monoalkanoate, hexaethylene glycerol hexadecyl ether, and heptane (Non-Patent Document 2).

[0005] However, reverse vesicle compositions having a lamellar structure have considerably poor stability, since the electrostatic repulsion force cannot be attained due to an oily continuous phase, which is problematic.

[Non-Patent Document 1]
Hironobu Kunieda et al., Langmuir, 1991, 7, 1915-1919

[Non-Patent Document 2]
Hironobu Kunieda et al., J. Phys. Chem., 1993, 97, 9525-9531


Summary of the Invention



[0006] The present invention provides a reverse vesicle composition which has excellent stability and provides good sensation in use.

[0007] The present inventor has found that, through use of the combination of a sphingosine, which is originally present in the skin, a salt derived from a specific fatty acid serving as an emulsifying agent, a hydrocarbon oil, and an ester oil, in specific compositional proportions, there can be produced a reverse vesicle composition which is stable for a long period, provides good sensation in use thereof, and exhibits an excellent moisturizing effect.

[0008] The present invention provides a method for producing a composition having a reverse vesicle structure according to claim 1.

[0009] As used herein, the term "reverse vesicle" refers to a microstructure containing an oil phase surrounded by a bilayer membrane formed of a lipid or an amphipathic compound having a hydrophilic moiety and a lipophilic moiety. The term "reverse vesicle structure" refers to a structure in which the hydrophobic moiety of the amphipathic compound having a hydrophilic moiety and a lipophilic moiety is aligned so as to face the oil phase, and the hydrophilic moiety forms the inner structure of the bilayer membrane.

[0010] The reverse vesicle composition is stable in a wide temperature range (from low to high), provides good sensation in use thereof, easily permeates the skin, and exhibits an excellent moisturizing effect.

Detailed Description of the Invention



[0011] The sphingosine serving as the ingredient (A) employed in the present invention is represented by the aforementioned formula (1).

[0012] In formula (1), R1 is a C4 to C30 linear alkyl group which may be substituted by a hydroxyl group, a carbonyl group, or an amino group, preferably a C7 to C24 linear alkyl group which may be substituted by a hydroxyl group. More preferred are a C10 to C24 linear alkyl group and a C10 to C24 linear alkyl group having a hydroxyl group on the carbon atom bonding to Y in formula (1). Specific examples of preferred alkyl groups include tridecyl, tetradecyl, pentadecyl, hexadecyl, 1-hydroxytridecyl, and 1-hydroxypentadecyl.

[0013] Y represents a methylene group (CH2), a methine group (CH), or an oxygen atom.

[0014] Each of X1, X2, and X3 is a hydrogen atom, a hydroxyl group, or an acetoxy group. X4 is a hydrogen atom, an acetyl group, or a glyceryl group, or a substituent which forms an oxo group together with the adjacent oxygen atom. In a preferred embodiment, 0 to 1 of X1, X2, and X3 is a hydroxyl group, and the remaining groups are a hydrogen atom, and X4 is a hydrogen atom. When Y is a methine group, one of X1 and X2 is a hydrogen atom, and the other is absent. When X4 forms an oxo group, X3 is absent.

[0015] Each of R2 and R3 is a hydrogen atom, a hydroxyl group, a hydroxymethyl group, or an acetoxymethyl group. R3 is preferably a hydrogen atom.

[0016] The number of "a" is 2 or 3. When a is 2, Rs correspond to R4 and R5, and when a is 3, Rs correspond to R4, R5, and R6.

[0017] Each of R4, R5, and R6 represents a hydrogen atom, an amidino group, or a linear-chain alkyl group optionally having a substituent selected from among a hydroxyl group, a hydroxyalkoxy group, an alkoxy group, and an acetoxy group and containing 1 to 8 carbon atoms in total. The hydroxyalkoxy group which may be substituted by an alkyl group is preferably a C1 to C7 linear or branched hydroxyalkoxy group. The alkoxy is preferably a C1 to C7 linear or branched alkoxy group. Examples of R4, R5, and R6 include hydrocarbon groups each having 1 to 8 carbon atoms in total and being substituted by 1 to 6 substituents. Examples of the substituents include a hydrogen atom; linear- or branched- alkyl groups such as methyl, ethyl, propyl, 2-ethylhexyl, and isopropyl; alkenyl groups such as vinyl and allyl; an amidino group; hydroxyl groups such as hydroxymethyl, 2-hydroxyethyl, 1,1-dimethyl-2-hydroxyethyl, 2-hydroxypropyl, 2,3-dihydroxypropyl, 2-hydroxy-3-methoxypropyl, 2,3,4,5,6-pentahydroxyhexyl, 1,1-bis(hydroxymethyl)ethyl, 2-(2-hydroxyethoxy)ethyl, 2-methoxyethyl, 1-methyl-2-hydroxyethyl, 3-hydroxypropyl, 3-methoxypropyl, and 1,1-bis(hydroxymethyl)-2-hydroxyethyl; hydroxyalkoxy groups, and alkoxy groups.

[0018] Among them, more preferred are a hydrogen atom and alkyl groups each being substituted by 1 to 3 groups selected from among methyl, hydroxyl groups such as 2-hydroxyethyl, 1,1-dimethyl-2-hydroxyethyl, 1,1-bis(hydroxymethyl)ethyl, and 2-(2-hydroxyethoxy)ethyl, and hydroxyalkoxy groups.

[0019] The sphingosine represented by formula (1) is preferably a natural or natural-type sphingosine represented by formula (3):

(wherein R12 represents a C7 to C24 linear alkyl group which may be substituted by a hydroxyl group; Y1 represents a methylene group or a methine group; each of X8, X9, and X10 represents a hydrogen atom, a hydroxyl group, or an acetoxy group; X11 represents a hydrogen atom or forms an oxo group together with the adjacent oxygen atom (wherein when Y1 is a methine group, one of X8 and X9 is a hydrogen atom, and the other is absent, and when X11 forms an oxo group, X10 is absent); R13 represents a hydroxymethyl group or an acetoxymethyl group; a is a number of 2 or 3; each of (R1)a represents a hydrogen atom, an amidino group, or a linear alkyl group optionally having a substituent selected from among a hydroxyl group, a hydroxyalkoxy group, an alkoxy group, and an acetoxy group and containing 1 to 4 carbon atoms in total; and the broken line represents an optional unsaturated bond) or a derivative thereof (hereinafter, these compounds are collectively referred to as "natural sphingosine").

[0020] The group R12 is preferably a C7 to C24 linear alkyl group, more preferably a C13 to C24 linear alkyl group. The number of "a" is preferably 2, and each of (R1)a is preferably a hydrogen atom or a C1 to C4 linear alkyl group.

[0021] Specific examples of the natural sphingosine represented by formula (3) include sphingosine, dihydrosphingosine, phytosphingosine, sphingadienine, dehydrosphingosine, and dehydrophytosphingosine, which are all naturally occurring compounds, and N-alkyl derivatives thereof (e.g., N-methyl derivatives).

[0022] Regarding these sphingosines, either a natural type optically active form (D(+) form) or a non-natural type optically active form (L(-) form) may be used. Furthermore, a mixture of a natural type form and a non-natural type form may also be used. The relative configuration of the aforementioned compound may be of natural type, of non-natural type, or of mixed type.

[0023] Examples of preferred sphingosines further include phytosphingosine (INCI nomenclature; 8th Edition) and the compounds represented by the following formulas.











m = 15 to 17, 1 = 1 to 13

[0024] These compounds may be a natural extract or a synthetic compound, and a commercial product thereof may be used.

[0025] Examples of the commercial product of natural sphingosine include D-sphingosine (4-sphingenine) (product of SIGMA-ALDRICH), DS-phytosphingosine (product of DOOSAN), and phytosphingosine (product of COSMOFERM).

[0026] The sphingosine of ingredient (A) forms with the below-described ingredient (B) an amphipathic salt having a hydrophilic moiety and a lipophilic moiety. The salt serves an ingredient forming a bilayer membrane in the below-described ingredients (C) and (D).

[0027] One or more species of ingredient (A) may be used. The total ingredient (A) content of the composition is preferably 0.001 to 10 mass%, more preferably 0.005 to 3 mass%, even more preferably 0.01 to 3 mass%, from the viewpoints of formation of the reverse vesicle and the stability of the formed reverse vesicle.

[0028] The fatty acid of ingredient (B) employed in the method of the present invention forms a salt through acid-base neutralization with an amine group(s) of the sphingosine, to thereby cationize the sphingosine, forming a hydrophilic moiety. The thus-formed salt is thought to serve as an agent like a surfactant. The thus-formed sphingosine salt may be identified through a conventional method for determining the structure of a compound; such as infrared absorption spectrometry or proton nuclear magnetic resonance spectrometry.

[0029] The fatty acid serving as ingredient (B) is required to have 16 to 30 carbon atoms. From the viewpoints of easy formation of a bilayer membrane of the vesicle composition, a C16 to C22 saturated or unsaturated fatty acid is preferred. When a C16 to C30 fatty acid is employed, a reverse vesicle composition which is stable in a mixed-type oil medium can be produced. Specific examples of the fatty acid include saturated fatty acids such as palmitic acid, stearic acid, eicosanoic acid, and behenic acid; and unsaturated fatty acids such as oleic acid, linoleic acid, linolenic acid, recinoleic acid, eicosapentaenoic acid, and docosahexaenoic acid.

[0030] Of these, C16 to C22 linear-chain saturated fatty acids are preferred, with palmitic acid, stearic acid, and behenic acid being more preferred, from the viewpoints of good sensation of use of the composition and stability of the composition.

[0031] One or more species of the fatty acids of ingredient (B) may be used. The total ingredient (B) content of the composition is preferably 0.001 to 10 mass%, more preferably 0.005 to 6 mass%, even more preferably 0.01 to 3 mass%, from the viewpoints of formation of bilayer membrane and the stability of the formed reverse vesicle.

[0032] In order to cationize the amine group(s) of the sphingosine serving as ingredient (A), the composition preferably contain ingredient (B) in an amount of 0.3 mol or more with respect to 1 mole of ingredient (A), more preferably 0.3 to 5 mol, even more preferably 0.5 to 3 mol, from the viewpoints of formation of reverse vesicle and the stability of the formed reverse vesicle.

[0033] The hydrocarbon oil serving as ingredient (C) employed in the method of the present invention includes those which are in the liquid, semi-solid, or solid form at 25°C and are synthetic or natural products. Examples of the liquid hydrocarbon oil include liquid lanolin, liquid paraffin, liquid isoparaffin, α-olefin oligomer, polybutene, hydrogenated polyolefin, and squalane, and examples of the semi-solid or solid hydrocarbon oil include waxes such as vaseline, lanolin, ceresine, and microcrystalline wax.

[0034] Among them, liquid hydrocarbon oils are preferred, with liquid isoparaffin, α-olefin oligomer, polybutene, squalane, etc. being more preferred, from the viewpoint of the stability of reverse vesicle.

[0035] One or more species of the hydrocarbon oil of ingredient (C) may be used. The total ingredient (C) content of the composition is preferably 0.1 to 50 mass%, more preferably 0.1 to 30 mass%, even more preferably 1 to 15 mass%, from the viewpoint of the stability of the formed reverse vesicle.

[0036]  The ester oil which is in liquid form at 25°C serving as ingredient (D) employed in the method of the present invention is preferably an ester of a fatty acid with cholesterol, a C12 to C22 higher alcohol, an alcohol having carbon atoms of 4 or less, or a polyhydric alcohol. Examples of such an ester include diisostearyl malate, octyldodecyl lactate, isopropyl palmitate, diisopropyl adipate, propylene glycol dicaprate, octyl isononanoate, phytosteryl isostearate, glyceryl triundecylate, glyceryl triisopalmitate, isotridecyl isononanoate, isopropyl isostearate, octyldodecyl myristate, and cholesterol isostearate. However, the ester (D) does not include esters formed from a sugar and a fatty acid.

[0037] Among them, isopropyl palmitate, diisopropyl adipate, propylene glycol dicaprate, octyl isononanoate, phytosteryl isostearate, glyceryl triundecylate, glyceryl triisopalmitate, and cholesterol isostearate are preferred.

[0038] One or more species of the ester oil of ingredient (D) may be used. The total ingredient (D) content of the composition is preferably 0.01 to 50 mass%, more preferably 0.01 to 30 mass%, even more preferably 0.1 to 15 mass%, from the viewpoint of the stability of the formed reverse vesicle.

[0039] The ratio by mass of ingredient (C) to ingredient (D) satisfies the following relationship: 1≤(C)/(D)<1000, preferably 9≤(C)/(D)≤70, more preferably 9≤(C)/(D)≤10.

[0040] Through controlling the ratio by mass (C)/(D) to fall within the aforementioned ranges, the amphipathic compound formed from ingredients (A) and (B) yields a robust bilayer membrane, and a reverse vesicle composition having high stability can be produced.

[0041] The composition may further contain (E) a ceramide. The ceramide is preferably employed, since it aligns at the interface in the bilayer membrane formed of an amphipathic compound produced from ingredients (A) and (B), to thereby further enhance the stability of the formed reverse vesicle.

[0042] The ceramide is preferably a compound represented by formula (2):

(wherein R7 represents a hydrogen atom or a C4 to C30 linear, branched or cyclic, saturated or unsaturated hydrocarbon group which may be substituted by a hydroxyl group, a carbonyl group, or an amino group; Z represents a methylene group, a methine group, or an oxygen atom; each of X5, X6, and X7 represents a hydrogen atom, a hydroxyl group, or an acetoxy group; X4 represents a hydrogen atom, an acetyl group, or a glyceryl group, or forms an oxo group together with the adjacent oxygen atom (wherein when Z is a methine group, one of X5 and X6 is a hydrogen atom, and the other is absent, and when X4 forms an oxo group, X7 is absent); each of R8 and R9 represents a hydrogen atom, a hydroxyl group, a hydroxymethyl group, or an acetoxymethyl group; R10 represents a C5 to C60 linear-chain, branched-chain or cyclic, saturated or unsaturated hydrocarbon group which may be substituted by a hydroxyl group, a carbonyl group, or an amino group, and which may have an ether bond, an ester bond, or an amido bond in a main chain thereof; R11 represents a hydrogen atom or a linear-chain or branched-chain, saturated or unsaturated hydrocarbon group optionally having a substituent selected from among a hydroxyl group, a hydroxyalkoxy group, an alkoxy group, and an acetoxy group and containing 1 to 30 carbon atoms in total (wherein, when R7 is a hydrogen atom and Z is an oxygen atom, R11 is a hydrocarbon group having 10 to 30 carbon atoms in total, and when R7 is a hydrocarbon group, R11 is a hydrocarbon group having 1 to 8 carbon atoms in total); and the broken line represents an optional unsaturated bond).

[0043] In formula (2), R7 is a hydrogen atom or a linear, branched or cyclic, saturated or unsaturated hydrocarbon group optionally having a substituent selected from among a hydroxyl group, a carbonyl group, or an amino group (preferably a hydroxyl group) and containing 4 to 30 (preferably 7 to 22) carbon atoms in total.

[0044] Z represents a methylene group, methine group, or an oxygen atom.

[0045] Each of X5, X6, and X7 represents a hydrogen atom, a hydroxyl group, or an acetoxy group. Preferably, 0 to 1 of X5, X6, and X7 is a hydroxyl group, and each remaining group is a hydrogen atom. When Z is a methine group, only one of X5 and X6 is a hydrogen atom, and the other is absent. X4 is preferably a hydrogen atom or a glyceryl group.

[0046] Each of R8 and R9 is a hydrogen atom, a hydroxyl group, a hydroxymethyl group, or an acetoxymethyl group. Preferably, R8 is a hydrogen atom or a hydroxymethyl group, and R9 is a hydrogen atom.

[0047] R10 represents a C5 to C60 linear, branched, or cyclic, saturated or unsaturated hydrocarbon group which may be substituted by a hydroxyl group, a carboxyl group, or an amino group, and which may have an ether bond, an ester bond, or an amido bond in a main chain thereof. R10 is preferably a C5 to C35 linear-chain, branched-chain, or cyclic, saturated or unsaturated hydrocarbon group which may be substituted by a hydroxyl group or an amino group, or such a hydrocarbon group to which a C8 to C22 linear, branched, or cyclic, saturated or unsaturated fatty acid which may be substituted by a hydroxyl group is bonded at the ω-position via ester bonding or amido bonding. The fatty acid bonding to R10 is preferably isostearic acid, 12-hydroxystearic acid, or linoleic acid.

[0048] R11 represents a hydrogen atom or a linear or branched, saturated or unsaturated hydrocarbon group optionally having a substituent selected from among a hydroxyl group, a hydroxyalkoxy group, an alkoxy group, and an acetoxy group and containing 1 to 30 carbon atoms in total. When R7 is a hydrogen atom and Z is an oxygen atom, R11 is a hydrocarbon group having 10 to 30 carbon atoms in total. When R7 is a hydrocarbon group, R11 is a hydrocarbon group having 1 to 8 carbon atoms in total. R11 is preferably a hydrogen atom, or a hydrocarbon group having 1 to 8 carbon atoms in total which group may be substituted by 1 to 3 substituents selected from among a hydroxyl group, a hydroxyalkoxy group, and an alkoxy group. Preferably, the hydroxyalkoxy group and the alkoxy group each have 1 to 7 carbon atoms.

[0049] The ceramide represented by formula (2) is preferably a ceramide represented by the following formula (4) or (5).
  1. (I): Natural or natural-type ceramide and derivatives thereof (hereinafter referred to as "natural ceramide") represented by formula (4):

    (wherein R21 represents a C7 to C19 linear, branched or cyclic, saturated or unsaturated hydrocarbon group which may be substituted by a hydroxyl group; Z1 represents a methylene group or a methine group; each of X12, X13, and X14 represents a hydrogen atom, a hydroxyl group, or an acetoxy group; X15 represents a hydrogen atom, or forms an oxo group together with the adjacent oxygen atom (wherein when Z1 is a methine group, one of X12 and X13 is a hydrogen atom, and the other is absent, and when X15 forms an oxo group, X14 is absent) ; R22 represents a hydroxymethyl group or an acetoxymethyl group; R23 represents a hydrogen atom or a C1 to C4 alkyl group; R24 represents a C5 to C30 linear, branched or cyclic, saturated or unsaturated hydrocarbon group which may be substituted by a hydroxyl group, or such an alkyl group to which a C8 to C22 linear or branched, saturated or unsaturated fatty acid which may be substituted by a hydroxyl group is bonded at the ω-end via ester bonding; and the broken line represents an optional unsaturated bond).
    In a preferred compound, R21 is a C7 to C19 (more preferably C13 to C15) linear alkyl group; R24 is a C9 to C27 linear alkyl group which may be substituted by a hydroxyl group, or a C9 to C27 linear alkyl group to which linoleic acid is bonded via ester bonding. Preferably, X15 is a hydrogen atom or forms an oxo group together with an oxygen atom. R24 is preferably tricosyl, 1-hydroxypentadecyl, 1-hydroxytricosyl, heptadecyl, 1-hydroxyundecyl, or nonacosyl to which linoleic acid is bonded at the ω-position via ester bonding.
    Specific examples of the natural ceramide include sphingosine, dihydrosphingosine, phytosphingosine, and amidated sphingadienines (ceramides of Types 1 to 7) (see, for example, pig-origin and human-origin ceramides shown in Fig. 2 in J. Lipid Res., 24: 759 (1983) and Fig. 4 in J. Lipid. Res., 35: 2069 (1994)).
    The ceramides also encompass N-alkyl forms (e.g., N-methyl form) thereof.
    Regarding these ceramides, either a natural type optically active form (D(-) form) or a non-natural type optically active form (L(+) form) may be used. Furthermore, a mixture of a natural type form and a non-natural type form may also be used. The relative configuration of the aforementioned compound may be of natural type, of non-natural type, or of mixed type. Further, preferred are compounds: CERAMIDE 1, CERAMIDE 2, CERAMIDE 3, CERAMIDE 5, CERAMIDE 611, (INCI, 8th Edition), and those represented by the following formulas.








    These ceramides may be natural extracts or synthetic products. Commercial products thereof may also be employed in the invention.
    Examples of such natural ceramide commercial products include Ceramide I, Ceramide III, Ceramide IIIA, Ceramide IIIB, Ceramide IIIC, and Ceramide VI (COSMOFERM); Ceramide TIC-001 (Takasago International Corporation); CERAMIDE II (Quest International); DS-Ceramide VI, DS-CLA-Phytoceramide, C6-Phytoceramide, and DS-ceramide Y3S (DOOSAN); and CERAMIDE2 (Sederma).





  2. (II): Pseudo-ceramides represented by formula (5):


(wherein R25 represents a hydrogen atom or a C10 to C22 linear, branched, or cyclic, saturated or unsaturated hydrocarbon group which may be substituted by a hydroxyl group; X16 represents a hydrogen atom, an acetyl group, or a glyceryl group; R26 represents a C5 to C22 linear, branched, or cyclic, saturated or unsaturated hydrocarbon group which may be substituted by a hydroxyl group or an amino group, or such a hydrocarbon group to which a C8 to C22 linear, branched, saturated or unsaturated fatty acid which may be substituted by a hydroxyl group is bonded at the ω-end via ester bonding; and R27 represents a hydrogen atom or an alkyl group optionally having a substituent selected from among a hydroxyl group, a hydroxyalkoxy group, an alkoxy group, and an acetoxy group and containing 1 to 30 carbon atoms in total).

[0050] R26 is preferably nonyl, tridecyl, pentadecyl, undecyl to which linoleic acid is bonded at the ω-position thereof via ester bonding, pentadecyl to which linoleic acid is bonded at the ω-position thereof via ester bonding, pentadecyl to which 12-hydroxystearic acid is bonded at the ω-position thereof via ester bonding, or undecyl to which branched isostearic acid is bonded at the ω-position thereof via amido bonding.

[0051] When R25 is a hydrogen atom, R27 is an alkyl group optionally substituted by a hydroxyl group, a hydroxyalkoxy group, an alkoxy group, or an acetoxy group and containing 10 to 30 (preferably 12 to 20) carbon atoms in total. When R25 is a C10 to C22 linear, branched, or cyclic, saturated or unsaturated hydrocarbon group which may be substituted by a hydroxyl group, R27 is preferably a hydrogen atom or an alkyl group optionally substituted by a hydroxyl group, a hydroxyalkoxy group, an alkoxy group, or an acetoxy group and containing 1 to 8 carbon atoms in total. The hydroxyalkoxy or alkoxy group in R27 preferably contains 1 to 7 carbon atoms.





[0052] Preferred pseudo-ceramides represented by formula (5) are the case where R25 is hexadecyl, X16 is a hydrogen atom, R26 is pentadecyl, and R27 is hydroxyethyl; the case where R25 is hexadecyl, X16 is a hydrogen atom, R26 is nonyl, and R27 is hydroxyethyl; and the case where R25 is hexadecyl, X16 is glyceryl, R26 is tridecyl, and R27 is 3-methoxypropyl. More preferred pseudo-ceramides represented by formula (5) are the case where R25 is hexadecyl, X16 is a hydrogen atom, R26 is pentadecyl, and R27 is hydroxyethyl.





[0053] One or more species of ceramides serving as ingredient (E) may be used. The total ingredient (E) content of the composition is preferably 0.0001 to 10 mass%, more preferably 0.001 to 3 mass%, even more preferably 0.01 to 1 mass%.

[0054] The reverse vesicle composition contains water (F) preferably in an amount of 1 to 90 mass% with respect to the total amount of the composition, more preferably 7 to 70 mass%, even more preferably 15 to 60 mass%.

[0055] The reverse vesicle composition contains a surfactant having a molecular weight of 1,000 or less in an amount of 1 mass% or less, preferably 0.5 mass% or less, even more preferably 0.1 mass% or less. When the structure formed from ingredients (A) and (B) contains a large amount of such a surfactant, the surfactant impairs the orderness of the structure. As a result, the reverse vesicle structure is not stabilized, and in some cases, the reverse vesicle structure per se fails to be formed.

[0056] In addition to the aforementioned ingredients, the reverse vesicle composition may further contain ingredients generally employed in cosmetics. Examples of such additional ingredients include oily ingredients other than the aforementioned oily ingredients such as silicone oil; moisturizers such as 1,3-butylene glycol, propylene glycol, dipropylene glycol, glycerin, diglycerin, sorbitol, maltitol, polyethylene glycol, glycine betaine, xylytol, trehalose, mannitol, erythritol, urea, and amino acids; aqueous thickeners such as xanthane gum, hydroxyethyl cellulose, methyl cellulose, and hydroxypropyl guar gum; drug ingredients such as allantoin and tocopheryl acetate; organic material powders such as cellulose powder, nylon powder, urethane powder, cross-linked silicone powder, cross-linked methylpolysiloxane, porous cellulose powder, and porous nylon powder; powders of inorganic material such as anhydrous silica, zinc oxide, or titanium oxide; refreshing flavoring agents such as mentol and camphore; and other additives such as pH-buffers, anti-oxidants, UV-absorbers, preservatives, perfumes, sterilizing agents, and colorants.

[0057] Hitherto, production and practical use of a reverse vesicle composition have been thought to be very difficult. However, according to the present invention, a reverse vesicle composition can be produced through the following conceivable mechanism.

[0058] When ingredients (A), (B), and (C), and water are combined, a W/O emulsion is formed. When an ester oil which is in the form of liquid at 25°C is added to the W/O emulsion, the layer formed from ingredients (A) and (B) at the water-oil interface is solubilized, to thereby be readily mixed with the oil phase, considerably reducing stability of the layer and resulting in difficulty in emulsification. Therefore, in the case where the product contains a large amount of ester oil in the form of liquid at 25°C, a sphingosine having a linear-chain alkyl group is combined with a fatty acid (particularly linear saturated fatty acid). Conceivably, in this case, interaction between alkyl chains in the layer formed from ingredients (A) and (B) is enhanced, and the bi-layer structure (bilayer membrane structure) is stabilized. In addition, a layer formed merely from ingredients (A) and (B), having high crystallinity, does not form a soft bi-layer film (bilayer membrane). However, conceivably, through incorporation of a specific amount of the ester oil, the crystallinity of the layer decreases to a certain degree, and a soft bi-layer film (bilayer membrane) can be produced, whereby a stable reverse vesicle composition can be produced.

[0059] As compared with simple application of a W/O emulsion to the skin, the reverse vesicle composition of the present invention exhibits a higher skin-permeation property. As a result, skin occlusive effect can be enhanced, whereby the barrier function of the skin and moisturized sensation of the skin can be enhanced. In W/O emulsion, water is dispersed in oil, and at the interface therebetween, a hydrophilic portion of a hydrophobic surfactant is oriented toward water (inside), while a hydrophobic portion thereof is oriented toward oil (outside). In contrast, the reverse vesicle composition has a liquid crystal structure at the W/O interface, and assumes a lipid bi-layer film whose hydrophobic portions are oriented toward both the inside and outside. Thus, the continuous phase and the enclosed phase assume an oil phase. Therefore, as compared with a conventional W/O emulsion, the reverse vesicle composition is highly compatible with the skin, and permeability of the composition is enhanced by virtue of the liquid crystal structure formed at the W/O interface.

[0060] The reverse vesicle composition may be produced through mixing ingredients (A) to (D) and optional ingredient (E), to thereby form an oil phase; heating the oil phase at a temperature at which the ingredients are dissolved or higher; adding, to the oil phase , an aqueous phase which contains ingredient (F) and an optional water-soluble ingredient and which has been heated to a temperature equivalent to the temperature of the oil phase, to thereby form an emulsion; and cooling the emulsion to room temperature. When the emulsion is cooled to room temperature, the rotation rate of the employed stirring apparatus is controlled while the conditions of the emulsion are visually observed so as to prevent discharge of water. The rotation rate is preferably adjusted such that power consumption per unit volume of the emulsion is controlled to fall within a range of 1,000 W/m3/h (W: watts required for stirring, m3: volume of the composition stirred, and h: time) to 100,000 W/m3/h, more preferably 3,000 W/m3/h to 50,000 W/m3/h. More specifically, the rotation rate of the stirring apparatus (e.g., homogenizer, propeller) may be adjusted by monitoring the indicated current amperage (A).

[0061] Formation of the reverse vesicle may be confirmed through a method generally employed for observing liquid crystal. For example, during observation of the composition through polarization microscopy, when anisotropy at the vesicle interface (i.e., an anisotropic pattern attributed to a structure indicating the presence of non-reverse micelle) is observed, formation of the reverse vesicle can be confirmed. More specifically, formation of the reverse vesicle can be confirmed by the presence of a Maltese cross (allowing more clear observation, by observation under an electron microscope).

[0062] The reverse vesicle composition may be used as a cosmetic product or a pharmaceutical product. Particularly, the composition of the present invention is preferably employed as a cosmetic product such as a milky lotion, cream, foundation, hair cream, more preferably as a cream-type cosmetic product.

Examples


Examples 1 to 8, and Comparative Examples 1 to 4



[0063] Compositions each having a formulation as shown in Tables 1 and 2 were produced. Formation of a reverse vesicle and the stability of the formed vesicle formation were confirmed with respect to the produced compositions. Tables 1 and 2 also show the results.

(Production method)



[0064] In the production of each composition, oil phase ingredients (A), (B), (C), and (D) were heated at 90°C for melting, and the melt was stirred, to thereby form a uniform oily mixture. An aqueous phase ingredient which had been heated to 90°C was added to the oily mixture, and the resultant mixture was emulsified. Subsequently, the emulsion was cooled at a cooling rate of 1 degree/min. During cooling, the rotation rate was adjusted so as to prevent water discharge through application of shear, whereby the power consumption per volume was adjusted to about 3,000 W/m3/h. As a production apparatus, an agi-homo-mixer 2M-2 (2L size) (product of Tokushukika) was employed.

(Evaluation methods)


(1) Formation of reverse vesicle:



[0065] Each as-produced composition was observed through a method generally employed for observing liquid crystal under a polarization microscope, whereby formation of reverse vesicle was confirmed.

(2) Stability:



[0066] Each composition was allowed to stand for one week at 50°C, room temperature (25°C), and -5°C. The appearance of the composition was visually observed and evaluated on the basis of the following ratings. Specifically, the number of reverse vesicles remaining after one week storage and observed in a vision field (×100) under a polarization microscopy was counted, and percent reverse vesicle remaining was calculated with respect to 100%, corresponding to the number of reverse vesicles observed immediately after the production of the composition and in a vision field (×100) under a polarization microscopy.
  1. A: 60% or more of reverse vesicles remained
  2. B: 10% or more, but less than 60% of reverse vesicles remained
  3. C: Virtually no reverse vesicle was observed
[Table 1]
Ingredients (mass%)ExamplesComparative Examples
12312
  Alkyl-branch pseudo-sphingosine*1       0.2  
A Sphingosine     0.2    
A Phytosphingosine 0.2 0.2     0.2
  Myristic acid         0.3
B Palmitic acid   0.3   0.3  
B Behenic acid 0.3   0.3    
C Squalane 6 6 6 6 6
C Liquid isoparaffin 3 3 3 3 3
D Cholesteryl isostearate 1 1 1 1 1
E Pseudo-ceramide *2 0.4 0.4 0.4 0.4 0.4
  Dimethylpolysiloxane (6cs) 5 5 5 5 5
  Dimethylcyclopolysiloxane (D5) 8.4 8.4 8.4 8.4 8.4
  Silicone polymer (KSG16) 5 5 5 5 5
  Glycerin 16 16 16 16 16
  Dipropylene glycol 3 3 3 3 3
  Purified water balance balance balance balance balance
Total 100 100 100 100 100
(C)/(D) 9 9 9 9 9
Presence of reverse vesicle yes yes yes no no
Stability: 50°C A B A C C
  25°C A B A C C
  -5°C A B A C C
*1: (formula)


*2: Compound represented by formula (5) (R25 = hexadecyl; X16 = hydrogen; R26 = pentadecyl; and R27 = hydroxyethyl)
[Table 2]
Ingredients (mass%)ExamplesComp. Exs.
4567834
A Phytosphingosine 0.2 0.2 0.2 0.2 0.2 0.2 0.2
B Behenic acid 0.3 0.3 0.3 0.3 0.3 0.3 0.3
C Squalane 6 6 6 2 9 15 6
C Liquid isoparaffin 3 3 3 1 4.5 16 3
D Cholesteryl isostearate 0.13 0.3 0.9 3 0.015 0.03 10
E Pseudo-ceramide *2 0.4 0.4 0.4 0.4 0.4 0.4 0.4
  Dimethylpolysiloxane (6cs) 5 5 5 5 5 5 5
  Dimethylcyclopolysiloxane (D5) 8.4 8.4 8.4 8.4 8.4 8.4 8.4
  Silicone polymer (KSG16) 5 5 5 5 5 5 5
  Dimethicone copolyol (BY11-030) 2 2 2 2 2 2 2
  Glycerin 16 16 16 16 16 16 16
  Dipropylene glycol 3 3 3 3 3 3 3
  Purified water balance balance balance balance balance balance balance
Total 100 100 100 100 100 100 100
(C)/(D) 70 30 10 1 900 1,033 0.9
Presence of reverse vesicle yes yes yes yes yes no no
Stability: 50°C A A A B B C C
  25°C A A A B B C C
  -5°C A A A B B C C

Example 9 (Skincare cream)



[0067] A skincare cream having the following formulation was produced through the same method as employed for producing the compositions of Examples 1 to 8.

(Ingredients) 
Phytosphingosine 0.1 (mass%)
Behenic acid 0.15
Pseudo-ceramide*2 0.4
Squalane 6
Liquid isoparaffin 3
Dimethylpolysiloxane (6cs) 5
Decamethylcyclopentanesiloxane 8.4
Silicone polymer (KSG16) 5
Cholesteryl isostearate 1
Glycerin 16
Dipropylene glycol 3
Water balance

Example 10 (Skincare cream)



[0068] A skincare cream having the following formulation was produced through the same method as employed for producing the compositions of Examples 1 to 8.

(Ingredients) 
Phytosphingosine 0.05 (mass%)
Behenic acid 0.075
Pseudo-ceramide*2 0.4
Squalane 6
Liquid isoparaffin 3
Dimethylpolysiloxane (6cs) 5
Decamethylcyclopentanesiloxane 8.4
Silicone polymer (KSG16) 5
Cholesteryl isostearate 1
Glycerin 16
Dipropylene glycol 3
Water balance

Example 11 (UV-protect cream)



[0069] A UV-protect cream having the following formulation was produced through the same method as employed for producing the compositions of Examples 1 to 8.

(Ingredients) 
Phytosphingosine 0.05 (mass%)
Behenic acid 0.075
Octyl methoxycinnamate 5
t-Butylmethoxybenzoylmethane 1
PEG·PPG-19/19 dimethicone 5.2
Pseudo-ceramide*2 7
Liquid isoparaffin 3
Magnesium stearate 1
Squalane 3
Paraffin wax 0.5
Dimethicone/vinyldimethicone cross-polymer 5
Dimethylpolysiloxane (6cs) 5
Decamethylcyclopentanesiloxane 9
Glycerin 15
Dipropylene glycol 3
Thujopsis dolabrata extract 2
Seaweed extract 1
Eucalyptus extract 1
Magnesium sulfate 1
Methyl p-oxybenzoate 0.25
Tocopherol 0.1
Perfume 0.075
Water balance


[0070] In all the cream products of Examples 9 to 11, a reverse vesicle structure was observed. In addition, these products exhibited excellent stability in a wide temperature range, and gave good sensation in use thereof.


Claims

1. A method for producing a composition having a reverse vesicle structure, the composition comprising the following ingredients (A), (B), (C), (D), and (F):

(A) a sphingosine represented by formula (1):

wherein R1 represents a C4 to C30 linear-chain alkyl group which may be substituted by a hydroxyl group, a carbonyl group, or an amino group;

Y represents a methylene group, a methine group, or an oxygen atom; each of X1, X2, and X3 represents a hydrogen atom, a hydroxyl group, or an acetoxy group;

X4 represents a hydrogen atom, an acetyl group, or a glyceryl group, or forms an oxo group together with the adjacent oxygen atom;

wherein when Y is a methine group, one of X1 and X2 is a hydrogen atom, and the other is absent, and when X4 forms an oxo group, X3 is absent;

each of R2 and R3 represents a hydrogen atom, a hydroxyl group, a hydroxymethyl group, or an acetoxymethyl group; a is a number of 2 or 3;

each of the "a" groups of Rs represents a hydrogen atom, an amidino group, or a linear-chain alkyl group optionally having a substituent selected from among a hydroxyl group, a hydroxyalkoxy group, an alkoxy group, and an acetoxy group and containing 1 to 8 carbon atoms in total; and the broken line represents an optional unsaturated bond,

(B) a C16 to C30 fatty acid,

(C) a hydrocarbon oil,

(D) an ester oil which is in liquid form at 25°C, and

(F) water,

wherein the ratio by mass of ingredient (C) to ingredient (D) satisfies the following relationship:

and the composition contains a surfactant having a molecular weight of 1,000 or less in an amount of 1 mass% or less,
the method comprising the steps of mixing ingredients (A), (B), (C), and (D), to thereby form an oil phase;
heating the oil phase at a temperature at which ingredients (A), (B), and (C) are dissolved or higher;
adding, to the oil layer, an aqueous phase which contains ingredient (F) and which has been heated to a temperature equivalent to the temperature of the oil phase, to thereby form an emulsion; and
cooling the emulsion to room temperature.
 
2. The method for producing a composition having a reverse vesicle structure according to claim 1, wherein, during cooling the emulsion to room temperature, the emulsion is stirred such that the power consumption per unit volume of the emulsion is controlled to fall within a range of 1,000 W/m3/h to 100,000 W/m3/h; wherein

W: watts required for stirring,

m3: volume of the composition stirred, and

h: time.


 
3. The method for producing a composition having a reverse vesicle structure according to claim 1 or 2, wherein as ingredient (E), a ceramide represented by formula (2) is further mixed with the ingredients (A), (B), (C) and (D):

wherein R7 represents a hydrogen atom or a C4 to C30 linear, branched or cyclic, saturated or unsaturated hydrocarbon group which may be substituted by a hydroxyl group, a carbonyl group, or an amino group; Z represents a methylene group, a methine group, or an oxygen atom;

each of X5, X6, and X7 represents a hydrogen atom, a hydroxyl group, or an acetoxy group;

X4 represents a hydrogen atom, an acetyl group, or a glyceryl group, or forms an oxo group together with the adjacent oxygen atom;

wherein when Z is a methine group, one of X5 and X6 is a hydrogen atom, and the other is absent, and when X4 forms an oxo group, X7 is absent;

each of R8 and R9 represents a hydrogen atom, a hydroxyl group, a hydroxymethyl group, or an acetoxymethyl group; R10 represents a C5 to C60 linear, branched or cyclic, saturated or unsaturated hydrocarbon group which may be substituted by a hydroxyl group, a carbonyl group, or an amino group, and which may have an ether bond, an ester bond, or an amido bond in a main chain thereof;

R11 represents a hydrogen atom or a linear-chain or branched-chain, saturated or unsaturated hydrocarbon group optionally having a substituent selected from among a hydroxyl group, a hydroxyalkoxy group, an alkoxy group, and an acetoxy group and containing 1 to 30 carbon atoms in total;

wherein, when R7 is a hydrogen atom and Z is an oxygen atom, R11 is a hydrocarbon group having 10 to 30 carbon atoms in total, and when R7 is a hydrocarbon group, R11 is a hydrocarbon group having 1 to 8 carbon atoms in total; and the broken line represents an optional unsaturated bond.


 


Ansprüche

1. Verfahren zur Erzeugung einer Zusammensetzung mit einer umgedrehten Vesikelstruktur, wobei die Zusammensetzung die folgenden Bestandteile (A), (B), (C), (D) und (F) enthält:

(A) ein Sphingosin mit der Formel (1):

worin R1 eine lineare C4-30-Alkylgruppe ist, die durch eine Hydroxylgruppe, Carbonylgruppe oder Aminogruppe substituiert sein kann,

Y eine Methylengruppe, Methingruppe oder Sauerstoffatom ist, jedes von X1, X2 und X3 ein Wasserstoffatom, Hydroxylgruppe oder Acetoxygruppe ist,

X4 ein Wasserstoffatom, Acetylgruppe oder Glycerylgruppe ist oder eine Oxogruppe zusammen mit dem benachbarten Sauerstoffatom bildet,

worin dann, wenn Y eine Methingruppe ist, eines von X1 und X2 ein Wasserstoffatom ist und das andere abwesend ist und wenn X4 eine Oxogruppe ist, X3 abwesend ist,

jedes von R2 und R3 ein Wasserstoffatom, Hydroxylgruppe, Hydroxymethylgruppe oder Acetoxymethylgruppe ist; a eine Zahl von 2 oder 3 ist,

jede der "a"-Gruppen von Rs ein Wasserstoffatom, Amidinogruppe oder lineare Alkylgruppe, wahlweise mit einem Substituenten ausgewählt aus einer Hydroxylgruppe, Hydroxyalkylgruppe, Alkoxygruppe und Acetoxygruppe und mit 1 bis 8 Kohlenstoffatomen insgesamt ist; und die gestrichelte Linie eine wahlweise ungesättigte Bindung ist,

(B) eine C16-30-Fettsäure,

(C) ein Kohlenwasserstofföl,

(D) ein Esteröl, das bei 25°C in flüssiger Form vorliegt, und

(F) Wasser,

worin das Massenverhältnis des Bestandteils (C) zum Bestandteil (D) die folgende Beziehung erfüllt:

und die Zusammensetzung ein Tensid mit einem Molekulargewicht von 1000 oder weniger in einer Menge von 1 Massen-% oder weniger enthält,
wobei das Verfahren die Schritte des Mischens der Bestandteile (A), (B), (C) und (D), unter Bildung einer Ölphase,
Erwärmen der Ölphase bei einer Temperatur, bei der die Bestandteile (A), (B) und (C) aufgelöst sind, oder höher,
Zugabe einer wässrigen Phase zu der Ölschicht, wobei die wässrige Phase einen Bestandteil (F) enthält und auf eine Temperatur erwärmt ist, die zu der Temperatur der Ölphase äquivalent ist, unter Bildung einer Emulsion, und
Kühlen der Mischung auf Raumtemperatur enthält.
 
2. Verfahren zur Erzeugung einer Zusammensetzung mit einer umgekehrten Vesikelstruktur nach Anspruch 1, worin während der Kühlung der Emulsion auf Raumtemperatur die Emulsion so gerührt wird, dass der Energieverbrauch pro Einheitsvolumen der Emulsion so eingestellt wird, dass er innerhalb des Bereiches von 1000 bis 100000 W/m3/h fällt, worin

W: Watt, das zum Rühren erforderlich ist,

m3: Volumen der gerührten Zusammensetzung und

h: Zeit.


 
3. Verfahren zur Erzeugung einer Zusammensetzung mit einer umgekehrten Vesikelstruktur nach Anspruch 1 oder 2, worin als Bestandteil (E) ein Ceramid mit der Formel (2) weiter mit den Bestandteilen (A), (B), (C) und (D) vermischt wird:

worin R7 ein Wasserstoffatom oder eine lineare, verzweigte oder cyclische, gesättigte oder ungesättigte C4-30-Kohlenwasserstoffgruppe ist, die durch eine Hydroxylgruppe, Carbonylgruppe oder Aminogruppe substituiert sein kann, Z eine Methylengruppe, Methingruppe oder Sauerstoffatom ist,

jedes von X5, X6 und X7 ein Wasserstoffatom, Hydroxylgruppe oder Acetoxygruppe ist,

X4 ein Wasserstoffatom, Acetylgruppe oder Glycerylgruppe ist oder eine Oxygruppe zusammen mit dem benachbarten Sauerstoffatom bildet,

worin dann, wenn Z eine Methingruppe ist, eines von X5 und X6 ein Wasserstoffatom ist und das andere abwesend ist, und wenn X4 eine Oxogruppe ist, X7 abwesend ist,

jedes von R8 und R9 ein Wasserstoffatom, Hydroxylgruppe, Hydroxymethylgruppe oder Acetoxymethylgruppe ist; R10 eine lineare, verzweigte oder cyclische, gesättigte oder ungesättigte C5-60-Kohlenwasserstoffgruppe ist, die durch eine Hydroxylgruppe, Carbonylgruppe oder Aminogruppe substituiert sein kann und die eine Etherbindung, Esterbindung oder Amidobindung in einer Hauptgruppe davon aufweisen kann,

R11 ein Wasserstoffatom oder eine lineare oder verzweigte, gesättigte oder ungesättigte Kohlenwasserstoffgruppe, wahlweise mit einem Substituenten ist, ausgewählt aus einer Hydroxylgruppe, Hydroxyalkylgruppe, Alkoxygruppe und Acetoxygruppe und mit 1 bis 30 Kohlenstoffatomen insgesamt ist,

worin dann, wenn R7 ein Wasserstoffatom und Z ein Sauerstoffatom ist, R11 eine Kohlenwasserstoffgruppe mit 10 bis 30 Kohlenstoffatomen insgesamt ist und wenn R7 eine Kohlenwasserstoffgruppe ist, R11 eine Kohlenwasserstoffgruppe mit 1 bis 8 Kohlenstoffatomen insgesamt ist und die gestrichelte Linie eine wahlweise ungesättigte Bindung ist.


 


Revendications

1. Procédé pour produire une composition ayant une structure de vésicule inversée, la composition comprenant les constituants (A), (B), (C), (D) et (F) suivants :

(A) une sphingosine représentée par la formule générale (1) :

dans laquelle R1 représente un groupement alkyle à chaîne linaire de 4 à 30 atomes de carbone qui peut être remplacé par un groupement hydroxyle, un groupement carbonyle, ou un groupement amino ;

Y représente un groupement méthylène, un groupe méthine, ou un atome d'oxygène ; chacun des X1, X2 et X3 représente un atome d'hydrogène, un groupement hydroxyle, ou un groupement acétoxy ;

X4 représente un atome d'hydrogène, un groupement acétyle, ou un groupement glycéryle, ou forme un groupement oxo avec l'atome d'oxygène adjacent ;

dans laquelle quand Y est un groupement méthine, l'un de X1 et de X2 est un atome d'hydrogène, et l'autre est absent, et quand X4 forme un groupement oxo, X3 est absent ;

chacun de R2 et de R3 représente un atome d'hydrogène, un groupement hydroxyle, un groupement hydroxyméthyle, ou un groupement acétoxyméthyle ; a est un nombre de 2 ou 3 ;

chacun des « a » groupements de Rs représente un atome d'hydrogène, un groupement amidino, ou un groupement alkyle à chaîne linéaire ayant optionnellement un substituant sélectionné parmi un groupement hydroxyle, un groupement hydroxyalcoxy, un groupement alcoxy, et un groupement acétoxy et contenant de 1 à 8 atomes de carbone au total ; et la ligne brisée représente une liaison insaturée optionnelle,

(B) un acide gras ayant 16 à 30 atomes de carbone,

(C) une huile hydrocarbonée,

(D) une huile d'ester qui est à l'état liquide à 25 °C, et

(F) de l'eau,

dans laquelle le rapport massique entre le constituant (C) et le constituant (D) satisfait la relation suivante : 1≤(C)/(D)<1000, et
la composition contient un tensioactif ayant un poids moléculaire égal ou inférieur à 1000 dans une quantité égale ou inférieure à 1 % en poids,
le procédé comprenant les étapes de mélange de constituants (A), (B), (C) et (D), pour ainsi former une phase huileuse ;
de chauffage de la phase huileuse à une température à laquelle les constituants (A), (B) et (C) sont dissous ou plus élevée ;
d'ajout à la couche huileuse, d'une phase aqueuse qui contient le constituant (F) et qui a été chauffée à une température équivalant à la température de la phase huileuse, pour ainsi former une émulsion ; et
de refroidissement de l'émulsion à température ambiante.
 
2. Procédé pour produire une composition ayant une structure de vésicule inversée selon la revendication 1, dans lequel, durant le refroidissement de l'émulsion à température ambiante, l'émulsion est agitée de telle sorte que la consommation d'énergie par volume unitaire de l'émulsion est régulée pour tomber dans une plage de 1 000 W/m3/h à 100 000 W/m3/h ; dans lequel

W : watts requis pour l'agitation,

m3 : volume de la composition agitée, et

h : temps.


 
3. Procédé pour produire une composition ayant une structure de vésicule inversée selon la revendication 1 ou 2, dans lequel en tant que constituant (E), un céramide représenté par la formule générale (2) est en outre mélangé aux constituants (A), (B), (C) et (D) :

dans laquelle R7 représente un atome d'hydrogène ou un groupement hydrocarbure saturé ou insaturé, linaire, ramifié ou cyclique ayant 4 à 30 atomes de carbone qui peut être remplacé par un groupement hydroxyle, un groupement carbonyle, ou un groupement amino ; Z représente un groupement méthylène, un groupement méthine, ou un atome d'oxygène ;

chacun des X5, X6 et X7 représente un atome d'hydrogène, un groupement hydroxyle, ou un groupement acétoxy ;

X4 représente un atome d'hydrogène, un groupement acétyle, ou un groupement glycéryle, ou forme un groupement oxo avec l'atome d'oxygène adjacent ;

dans laquelle quand Z est un groupement méthine, l'un de X5 et de X6 est un atome d'hydrogène, et l'autre est absent, et quand X4 forme un groupement oxo, X7 est absent;

chacun de R8 et de R9 représente un atome d'hydrogène, un groupement hydroxyle, un groupement hydroxyméthyle, ou un groupement acétoxyméthyle ; R10 représente un groupement hydrocarbure saturé ou insaturé, linaire, ramifié ou cyclique ayant 5 à 60 atomes de carbone qui peut être remplacé par un groupement hydroxyle, un groupement carbonyle, ou un groupement amino, et qui peut avoir une liaison d'éther, une liaison d'ester ou une liaison amido dans une chaîne principale de celui-ci ;

R11 représente un atome d'hydrogène ou un groupement hydrocarbure saturé ou insaturé, à chaîne linaire ou chaîne ramifiée ayant optionnellement un substituant sélectionné parmi un groupement hydroxyle, un groupement hydroxyalcoxy, un groupement alcoxy et un groupement acétoxy et contenant 1 à 30 atomes de carbone au total ;

dans laquelle, quand R7 est un atome d'hydrogène et Z est un atome d'oxygène, R11 est un groupement hydrocarbure ayant 10 à 30 atomes de carbone au total, et quand R7 est un groupement hydrocarbure, R11 est un groupement hydrocarbure ayant 1 à 8 atomes de carbone au total ; et la ligne brisée représente une liaison insaturée optionnelle.


 






Cited references

REFERENCES CITED IN THE DESCRIPTION



This list of references cited by the applicant is for the reader's convenience only. It does not form part of the European patent document. Even though great care has been taken in compiling the references, errors or omissions cannot be excluded and the EPO disclaims all liability in this regard.

Non-patent literature cited in the description