CROSS REFERENCE TO RELATED APPLICATIONS

This is a national stage application of PCT/EP2016/072462, filed internationally on Jul. 26, 2016, which claims priority to Japanese Application No. 2015-149542, filed on Jul. 29, 2015, both of which are incorporated by reference herein in their entireties.

TECHNICAL FIELD

The present invention relates to a composition, in particular a cosmetic composition, for a keratin substance such as skin.

BACKGROUND ART

The thickening or gelation of aqueous media with polymers has been the subject of research for a long time, especially in the cosmetic and pharmaceutical industries. In some cosmetic and pharmaceutical compositions, an associative thickener has been used for thickening and/or gelling the compositions.

The associative thickener is capable of reversibly associating with itself or with other molecules or particles. This physical association can give rise to thixotropic or shear-thinning macromolecular systems, i.e. systems whose viscosity depends on the shear forces to which they are subjected.

However, the use of an associative thickener may pose a certain number of problems, such as a rather unpleasant texture.

Furthermore, an associative thickener may cause soaping (foaming) on application, when it is used for an aqueous medium to prepare a transparent gel. The soaping is not preferable, because the foam prepared looks white and this appearance does not leave a good impression on consumers.

DISCLOSURE OF INVENTION

An objective of the present invention is to provide a composition, preferably a cosmetic composition for a keratin substance, such as skin, which can prevent soaping and can provide excellent texture, when used, while providing sufficient thickening or gelling effects.

The above objective of the present invention can be achieved by a composition comprising:(a) at least one associative thickener;(b) at least one alkyleneoxide derivative represented by the following chemical formula (I):
Z—{O(AO)l(EO)m-(BO)nH}a(I)whereinZ denotes a residue obtained by removing hydroxyl group(s) from a compound having 3 to 9 hydroxyl groups;AO denotes an oxyalkylene group having 3 to 4 carbon atoms;EO denotes an oxyethylene group;BO denotes an oxyalkylene group having 4 carbon atoms;a denotes 3 to 9;l, m, and n denote the average addition mole numbers of AO, EO and BO, respectively, and 1≤l≤50, 1≤m≤50 and 0.5≤n≤5;a weight ratio of AO to EO (AO/EO) ranges from 1/5 to 5/1; andAO and EO may have been added randomly or in the form of blocks;(c) at least one nonionic surfactant, other than (b), with an HLB value of 13.0 or less; and(d) water.

The (a) associative thickener may be an associative polymeric thickener, preferably an associative polyurethane thickener.

The (a) associative thickener may preferably be a nonionic associative polyurethane/polyether which has both at least one hydrophilic moiety and at least one hydrophobic moiety.

The (a) associative thickener may be selected from polyurethane/polyethers comprising in their chain at least one polyoxyethylenated hydrophilic block and at least one of hydrophobic blocks containing at least one sequence chosen from aliphatic sequences, cycloaliphatic sequences, and aromatic sequences, preferably polyurethane/polyethers comprising at least two hydrocarbon-based lipophilic chains having from 8 to 30 carbon atoms, separated by a hydrophilic block, and wherein the hydrocarbon-based chains are chosen from pendent chains and chains at the end of the hydrophilic block, and more preferably Steareth-100/PEG-136/HDI Copolymer, PEG-240/HDI Copolymer Bis-decyltetradeceth-20 ether, and mixtures thereof.

The amount of the (a) associative thickener in the composition may be from 0.01 to 10% by weight, preferably from 0.1 to 5% by weight, and more preferably from 0.3 to 1% by weight, relative to the total weight of the composition.

The (b) alkyleneoxide derivative may be represented by the following chemical formula (II):
Gly-{O(PO)s(EO)t-(BO)u—H}3(II)

wherein

Gly denotes a residue obtained by removing hydroxyl groups from glycerin;

PO denotes an oxypropylene group;

EO denotes an oxyethylene group;

s and t denote the average addition mole numbers of PO and EO, respectively, and have a value ranging from 1 to 50;

the weight ratio of PO to EO (PO/EO) ranges from 1/5 to 5/1;

BO denotes an oxyalkylene group having 4 carbon atoms; and

u denotes the average addition mole number of BO, and ranges from 0.5 to 5.

The amount of the (b) alkyleneoxide derivative in the composition may be from 0.01 to 10% by weight, preferably from 0.1 to 5% by weight, and more preferably from 0.5 to 2% by weight, relative to the total weight of the composition.

The (c) nonionic surfactant with an HLB value of 13.0 or less may be selected from:

(1) (1-40 EO) and polyoxypropylenated (5-30 PO) alkyl (C16-C30) ethers, and preferably (15-40 EO) and polyoxypropylenated (5-30 PO) alkyl (C16-C24) ethers;

(2) mono- or polyoxyethylenated fatty ethers/esters, preferably polyoxyethylenated fatty esters, and more preferably polyoxyethylenated C8-C40fatty ester having a polyoxyethylene moiety derived from 2 to 100 polyoxyethylenes;

(3) mono- or polyglycerolated fatty ethers/esters, preferably polyglycerolated fatty esters, and more preferably polyglycerolated C8-C40fatty ester having a polyglycerol moiety derived from 2 to 10 glycerols; and

(4) silicone surfactants, preferably dimethicone copolyol.

The amount of the (c) nonionic surfactant with an HLB value of 13.0 or less in the composition may be from 0.01 to 10% by weight, preferably from 0.05 to 5% by weight, and more preferably from 0.1 to 2% by weight, relative to the total weight of the composition.

The amount of the (d) water in the composition may be from 50 to 95% by weight, preferably from 60 to 90% by weight, and more preferably from 70 to 90% by weight, relative to the total weight of the composition.

The viscosity of the composition may be 530 mPa·s or more, preferably 550 mPa·s or more, and more preferably 580 mPa·s or more.

It is preferable that the composition according to the present invention be in the form of a gel, and more preferably a transparent gel.

The composition according to the present invention may be a cosmetic composition, preferably a cosmetic composition for a keratin substance, and more preferably a skin cosmetic composition.

The present invention also relates to a cosmetic process for a keratin substance such as skin, comprising the step of: applying onto the keratin substance the composition according to the present invention.

