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EP-4547732-B1 - POLYESTER POLYMER FOR USE IN HAIR CARE

EP4547732B1EP 4547732 B1EP4547732 B1EP 4547732B1EP-4547732-B1

Inventors

  • CHANDA, Sananda
  • SHIVANANDAREDDY, Avinash
  • MAKWANA, Ketan
  • CHAKRABORTY, Kaustav
  • WILSON, DAVID, JAMES
  • MASTROIANNI, SERGIO

Dates

Publication Date
20260506
Application Date
20230622

Claims (15)

  1. A polyester polymer prepared by polycondensation of at least the following monomers: (a) an aliphatic/aromatic unsulfonated dicarboxylic acid/ester; (b) an aliphatic diol; (c) an aliphatic/aromatic sulfonated dicarboxylic acid/ester; (d) an aliphatic/aromatic secondary or tertiary amine bearing two carboxylic acid/ester functions, or an aliphatic/aromatic quaternized amine bearing two carboxylic acid/ester functions.
  2. The polyester polymer according to claim 1, wherein the aliphatic/aromatic unsulfonated dicarboxylic acid/ester (a) is selected from: - alkyldicarboxylic acids/esters of formula ROOC-(CH2)n-COOR (I) where n = 2-4 and R is H, a C1 to C8 alkyl or phenyl group; - cyclopentanedicarboxylic acids/alkyl esters or cyclohexanedicarboxylic acids/alkyl esters, in particular 1,2-cyclopentanedicarboxylic acid, 1,3-cyclopentanedicarboxylic acid, 1,3-cyclohexanedicarboxylic acid or 1,4-cyclohexanedicarboxylic acid and their corresponding alkyl esters where the alkyl group can vary from methyl to octyl or can be a phenyl group; - terephthalic acid/alkyl esters and isophthalic acid/alkyl esters where the alkyl group can vary from methyl to octyl or can be a phenyl group.
  3. The polyester polymer according to claim 2, wherein the aliphatic/aromatic unsulfonated dicarboxylic acid/ester (a) is an aliphatic one, preferably a cyclohexane derivative, in particular 1,4-cyclohexanedicarboxylic acid (CHDA).
  4. The polyester polymer according to any one of claims 1 to 3, wherein the aliphatic diol (b) is selected from: - alkyl diols like ethylene glycol or propylene glycol, diethylene glycol, triethylene glycol; a polyethylene glycol having an ethylene oxide number ranging from ranging from 4 to 75; - cyclic saturated diols, preferably cyclopentane diols or cyclohexane diols, in particular 1,2-cyclopentane diol, 1,3-cyclopentane diol, 1,3-cyclohexane diol or 1,4-cyclohexane diol.
  5. The polyester polymer according to claim 4, wherein the aliphatic diol (b) is an alkyl diol, in particular ethylene glycol (EG).
  6. The polyester polymer according to any one of claims 1 to 5, wherein the aliphatic/aromatic sulfonated dicarboxylic acid/ester (c) is selected from: - isophthalic acid/esters, terephthalic acid/esters and naphthalenedicarboxylic acids/esters, in particular 2-sodiosulfoisophthalic acid/esters, 4-sodiosulfoisophthalic acid/esters, 5-sodiosulfoisophthalic acid/esters, 2-sodiosulfoterephthalic acid/esters, 2,6-dicarboxyl naphthalene-4-sodiosulfonic acid/esters and 2,6-dicarboxyl naphthalene-7-sodiosulfonic acid/esters; - dialkyl sodium sulfosuccinates.
  7. The polyester polymer according to claim 6, wherein the aliphatic/aromatic sulfonated (c) is an aromatic sulfonated dicarboxylic acid/ester, preferably 5-sodiosulfoisophthalic acid or an ester thereof, in particular 5-sodiosulfoisophthalic acid (SSIA).
  8. The polyester polymer according to any of claims 1 to 7, wherein monomer (d) is selected from: - N-methyldiethanolamine, ethylenediamine N,N' diacetic acid/alkyl diesters and iminodiacetic acid/ alkyl diesters, where the alkyl group can vary from methyl to octyl or can be a phenyl group; - pyridine derivatives like pyridine-2,6-dicarboxylic acid/alkyl diesters, pyridine-2,4-dicarboxylic acid/alkyl diesters, pyridine-3,5-dicarboxylic acid/alkyl diesters, pyridine-2,3-dicarboxylic acid/alkyl diesters and pyridine-2,5-dicarboxylic acid/alkyl diesters; of pyrazine derivatives like pyrazine-2,6-dicarboxylic acid/alkyl diesters, pyrazine-2,3-dicarboxylic acid/alkyl diesters and pyrazine-2,5-dicarboxylic acid/alkyl diesters; of imidazole derivatives like 1H-imidazole-2,5-dicarboxylic acid/alkyl diesters and 1H-imidazole-4,5-dicarboxylic acid/alkyl diesters; and of indole derivatives like 1H-indole-4,6-dicarboxylic acid/alkyl diesters, 1H-indole-2,5-dicarboxylic acid/alkyl diesters, 1H-indole-2,6-dicarboxylic acid/alkyl diesters, 1H-indole-3,5-dicarboxylic acid/alkyl diesters and 1H-indole-2,3-dicarboxylic acid/alkyl diesters, where the alkyl group can vary from methyl to octyl or can be a phenyl group.
  9. The polyester polymer according to any of claims 1 to 7, wherein monomer (d) is a quaternized form of an aromatic tertiary amine, preferably of a pyridine derivative, in particular of pyridine-2,6-dicarboxylic acid/esters, more particularly 2,6-bis(methoxycarbonyl)-1-methylpyridin-1-ium trifluoromethanesulfonate.
  10. The polyester polymer according to claim 8 or 9, wherein monomer (d) is an aromatic tertiary amine or quaternized amine, preferably pyridine-2,6-dicarboxylic acid (PDA) or 2,6-bis(methoxycarbonyl)-1-methylpyridin-1-ium trifluoromethanesulfonate (quatPDA).
  11. The polyester polymer according to any of claims 1 to 10, said polyester being prepared by polycondensation of the following monomers: (a) 1,4-cyclohexanedicarboxylic acid (CHDA); (b) ethylene glycol (EG); (c) 5-sodiosulfoisophthalic acid (SSIA); (d) pyridine-2,6-dicarboxylic acid (PDA) or 2,6-bis(methoxycarbonyl)-1-methylpyridin-1-ium trifluormethanesulfonate (quatPDA).
  12. A polyester polymer comprising the following repeat units: CHDA-EG, SSIA-EG and (quat)PDA-EG.
  13. A process for synthesizing a polyester polymer according to any of claims 1 to 11, said process comprising a step of polycondensation of monomers (a), (b), (c) and (d) in the presence of a catalyst, preferably a hydrolysis-stable catalyst, more preferably a chelate of a titanium salt or of zirconium salt derived from ethanol amines, in particular Titanium(IV) (triethanolaminato)isopropoxide.
  14. The process according to claim 13, wherein monomers (a), (b), (c) and (d) are first mixed and then reacted by polycondensation by raising temperature and/or reducing pressure.
  15. The use of a polyester polymer according to any of claims 1 to 12 or obtained by a process according to claim 13 or 14, in hair care compositions, in particular in hair straightening compositions.

Description

FIELD OF THE INVENTION The present invention provides a polyester polymer for use in hair care formulations, namely in hair straightening compositions. BACKGROUND OF THE INVENTION Human hair is made of keratin which in turn is made of polypeptide chains bonded together by disulfide bonds, hydrogen bonds and salt linkages. Temporary straightening, using physicochemical techniques such as dryer, flat iron and the old hot comb, lasts only until the next wash. More permanent straightening of hair can be achieved by chemically altering the disulfide bonds of keratin, but this weakens the hair fibers. Conditioning polymers can also improve the hair manageability and make the hair softer and smoother. Cationic polymers are preferred as they are hold by the negatively charged hair proteins by electrostatic forces, whereas nonionic polymers are more easily washed off by surfactants. However, most of the currently available conditioning polymers are not biodegradable so when they end up in wastewater, they potentially lead to the formation of microplastics. US 5662893 discloses an hair spray comprising a sulfopolyester which contains repeat units from 20 to 26 mole percent dimethyl-5-sodiosulfoisophthalate and 74 to 80 mole percent isophthalic acid, based on 100 mole percent dicarboxylic acid; 10 to 30 mole percent 1,4-cyclohexanedimethanol and 70 to 90 mole percent diethylene glycol, based on 100 mole percent diol. This document does not address the problem of long term hair straightening, but merely addresses the problem of providing human hair with a particular shape or configuration by applying a thin film of a resin or gum onto the hair to adhere adjacent hairs together so that they retain the particular shape or configuration at the time of application. It doesn't address the problem of degradability either. US 6 749 836 B1 discloses a hair care formulation comprising a sulfopolyester comprising the condensation polymerization product of inter alia sodiosulfoisophthalate, isophthalic acid and cyclohexanedimethanol. An object of the present invention is to provide a polyester polymer that is effective in long-term hair straightening. Another object of the present invention is to provide a polyester polymer that is biodegradable. In another aspect of the present invention, a method of synthesis for a polyester polymer is provided. Finally, the present invention also relates to the use of given polyester polymers in hair care compositions, especially in hair straightening compositions. DETAILED DESCRIPTION OF THE INVENTION The polyester polymer of the present invention is prepared by polycondensation of at least the following monomers: (a) an aliphatic/aromatic unsulfonated dicarboxylic acid/ester;(b) an aliphatic diol;(c) an aliphatic/aromatic sulfonated dicarboxylic acid/ester;(d) an aliphatic/aromatic secondary or tertiary amine bearing two carboxylic acid/ester functions, or an aliphatic/aromatic quaternized amine bearing two carboxylic acid/ester functions. The aliphatic unsulfonated dicarboxylic acid/ester according to the invention may be linear or cyclic. Preferred linear aliphatic unsulfonated dicarboxylic acids/esters according to the invention are alkyldicarboxylic acids/esters of formula ROOC-(CH2)n-COOR (I) where n = 2-4 and R is H, a C1 to C8 alkyl or phenyl group. Preferred cycloaliphatic unsulfonated dicarboxylic acids/esters according to the invention are based on cycles with 5 or 6 C atoms i.e. cyclopentanedicarboxylic acids/alkyl esters or cyclohexanedicarboxylic acids/alkyl esters, in particular 1,2-cyclopentanedicarboxylic acid, 1,3-cyclopentanedicarboxylic acid, 1,3-cyclohexanedicarboxylic acid or 1,4-cyclohexanedicarboxylic acid and their corresponding alkyl esters where the alkyl group can vary from methyl to octyl or can be a phenyl group. Preferred aromatic unsulfonated dicarboxylic acids/esters according to the invention are terephthalic acid/alkyl esters and isophthalic acid/alkyl esters where the alkyl group can vary from methyl to octyl or can be a phenyl group. The aliphatic/aromatic unsulfonated dicarboxylic acid/ester (a) of the invention is preferably an aliphatic one, more preferably a cyclohexane derivative. In particular 1,4-cyclohexanedicarboxylic acid (CHDA) gives good results in the frame of the present invention. The aliphatic diol used in the present invention can be a linear aliphatic diol selected from the group consisting of alkyl diols like ethylene glycol or propylene glycol, diethylene glycol, triethylene glycol or a polyethylene glycol having an ethylene oxide number ranging from 4 to 75. Alternatively, it can be a cyclic saturated diol preferably comprising 5 or 6 C atoms i.e. a cyclopentane diol or a cyclohexane diol, in particular 1,2-cyclopentane diol, 1,3-cyclopentane diol, 1,3-cyclohexane diol or 1,4-cyclohexane diol. Preferably, linear aliphatic diols are used, more preferably alkyl diols, in particular ethylene glycol (EG). The aliphatic/aromatic sulfonated