Novel inverse latices of copolymers of amps and of n,n-dimethylacrylamide; cosmetic use

Abstract

Composition comprising an oil phase, an aqueous phase, at least one emulsifying system of water-in-oil (W/O) type, optionally at least one emulsifying system of oil-in-water (O/W) type, in the form of an inverse latex comprising from 20% to 70% by mass and preferably from 25% to 50% by mass of a branched or crosslinked polyelectrolyte, characterized in that the said polyelectrolyte is a copolymer of 2-acrylamido-2-methylpropanesulfonic acid partially or totally salified with N,N-dimethylacrylamide and optionally one or more monomers chosen from monomers containing a partially or totally salified weak acid function and neutral monomers. Cosmetic use.

1 . A composition comprising:
 an oil phase;   an aqueous phase;   at least one water-in-oil (W/O) emulsifying system;   optionally at least one oil-in-water (O/W) emulsifying system; and   from 20% to 70% by mass of a branched or crosslinked polyelectrolyte, wherein,   said polyelectrolyte is a copolymer of partially or totally salified 2-acrylamido-2-methylpropanesulfonic acid, of N,N-dimethylacrylamide, and of one or more monomers chosen from monomers containing a weak acid function and/or neutral monomers other than N,N-dimethylacrylamide,   the mole proportion of all of the monomers chosen from the monomers containing a weak acid function and the neutral monomers other than N,N-dimethylacrylamide is greater than 0% and less than or equal to 30%,   the mole ratio between the N,N-dimethylacrylamide and all of the monomers chosen from the monomers containing a weak acid function and the neutral monomers other than N,N-dimethylacrylamide is greater than or equal to 1, and   said composition is an inverse latex.   
   
   
       2 . The composition according to  claim 1 , wherein the branched or crosslinked polyelectrolyte is 25% to 50% by mass. 
   
   
       3 . The composition according to  claim 1 , comprising an emulsifying system of oil-in-water (O/W) type. 
   
   
       4 . The composition according to  claim 1 , wherein the polyelectrolyte is selected from the group consisting of:
 crosslinked copolymers of 2-methyl-2-[(1-oxo-2-propenyl)amino]-1-propanesulfonic acid partially salified in the form of the sodium salt and of N,N-dimethylacrylamide,   crosslinked copolymers of 2-methyl-2-[(1-oxo-2-propenyl)amino]-1-propanesulfonic acid partially salified in the form of the ammonium salt and of N,N-dimethylacrylamide,   crosslinked copolymers of 2-methyl-2-[(1-oxo-2-propenyl)amino]-1-propanesulfonic acid partially salified in the form of the potassium salt and of N,N-dimethylacrylamide,   crosslinked terpolymers of 2-methyl-2-[(1-oxo-2-propenyl)amino]-1-propanesulfonic acid partially salified in the form of the sodium salt, of the potassium salt or of the ammonium salt, of acrylic acid partially salified in the form of the sodium salt, the potassium salt or the ammonium salt and of N,N-dimethylacrylamide,   crosslinked tetrapolymers of 2-methyl-2-[(1-oxo-2-propenyl)amino]-1-propanesulfonic acid partially salified in the form of the sodium salt, the potassium salt or the ammonium salt, of acrylic acid partially salified in the form of the sodium salt, the potassium salt or the ammonium salt, of N,N-dimethylacrylamide and of acrylamide,   crosslinked terpolymers of 2-methyl-2-[(1-oxo-2-propenyl)amino]-1-propanesulfonic acid partially salified in the form of the sodium salt, the potassium salt or the ammonium salt, of N,N-dimethylacrylamide and of acrylamide   crosslinked terpolymers of 2-methyl-2-[(1-oxo-2-propenyl)amino]-1-propanesulfonic acid partially salified in the form of the sodium salt, the potassium salt or the ammonium salt, of N,N-dimethylacrylamide and of N-isopropylacrylamide,   crosslinked terpolymers of 2-methyl-2-[(1-oxo-2-propenyl)amino]-1-propanesulfonic acid partially salified in the form of the sodium salt, the potassium salt or the ammonium salt, of N,N-dimethylacrylamide and of N-[2-hydroxy-1,1-bis(hydroxymethyl)ethyl]propenamide,   crosslinked tetrapolymers of 2-methyl-2-[(1-oxo-2-propenyl)amino]-1-propanesulfonic acid partially salified in the form of the sodium salt, the potassium salt or the ammonium salt, of acrylic acid partially salified in the form of the sodium salt, the potassium salt or the ammonium salt, of N,N-dimethylacrylamide and of (2-hydroxyethyl)acrylate, and   crosslinked terpolymers of 2-methyl-2-[(1-oxo-2-propenyl)amino]-1-propanesulfonic acid partially salified in the form of the sodium salt, the potassium salt or the ammonium salt, of N,N-dimethylacrylamide and of (2-hydroxyethyl)acrylate.   
   
   
       5 . A cosmetic, dermopharmaceutical or pharmaceutical composition, comprising as thickening and/or emulsifying compound at least one inverse latex as defined in  claim 1 . 
   
   
       6 . A sunscreen composition, comprising at least one sunscreen; and the inverse latex as defined in  claim 1 . 
   
   
       7 . A self-tanning composition, comprising an effective amount of dihydroxyacetone and the inverse latex as defined in  claim 1 . 
   
   
       8 . The cosmetic, dermopharmaceutical or pharmaceutical composition according to  claim 5 , further comprising:
 dihydroxyacetone; and   a component selected from the group consisting of lactic acid, gluconic acid, at least one sunscreen agent, at least a moisturizing agent, and caffeine.   
   
   
       9 . The sunscreen composition according to  claim 6 , further comprising:
 dihydroxyacetone; and   a component selected from the group consisting of lactic acid, gluconic acid, at least one sunscreen agent, at least a moisturizing agent, and caffeine.