Thickener containing a cationic polymer and softening composition containing said thickener, in particular for textiles

1. A method for softening laundry comprising the following steps:

providing a softening composition comprising at least one textile softener and at least one thickener, the at least one thickener containing a cationic polymer obtained by polymerization:

of a cationic monomer;

of a monomer with a hydrophobic nature, of formula (I):

wherein

R1=H or CH 3

R2=alkyl chain having at least 16 carbon atoms

X=O, m≧5, y=z=0;

of a nonionic monomer; and

applying the softening composition to at least one textile material during a laundering process.

2. The method of claim 1 further comprising the step of washing the at least one textile material as part of the laundering process and wherein said step of applying the softening composition is performed simultaneously with said washing step.

3. The method of claim 1 further comprising the step of washing the at least one textile material as part of the laundering process and wherein said step of applying the softening composition is performed subsequent to said washing step.

4. The method of claim 1 , wherein the thickener consists of a cationic terpolymer obtained by polymerization:

of a cationic monomer;

of a monomer with a hydrophobic nature, of formula (I):

wherein

R1=H or CH 3

R2=alkyl chain having at least 16 carbon atoms

X=O, m≧5, y=z=0;

of a nonionic monomer.

5. The method of claim 1 , wherein the hydrophobic monomer is selected from the group consisting of: ethoxylated cetyl methacrylate (EO 25), ethoxylated behenyl methacrylate (EO 25) and mixtures of these compounds.

6. The method of claim 1 , wherein the hydrophobic monomer is ethoxylated behenyl methacrylate (EO 25).

7. The method of claim 1 , wherein a content of hydrophobic monomer represents between 0.1% by weight and 20% by weight relative to the weight of the cationic polymer.

8. The method of claim 7 , wherein the content of hydrophobic monomer represents between 0.5% by weight and 5% by weight relative to the weight of the cationic polymer.

9. The method of claim 1 , wherein the cationic monomer is selected from the group consisting of: diallyldialkylammonium salts; acidified or quaternized salts of dialkylaminoalkyl acrylates and methacrylates; and acidified or quaternized salts of dialkyl- aminoalkylacrylamides or methacrylamides.

10. The method of claim 9 , wherein the cationic monomer is diallyldimethylammonium chloride (DADMAC).

11. The method of claim 9 , wherein the cationic monomer is selected from the group consisting of acidified or quaternized salts of dialkylaminoethyl acrylate (ADAME) and acidified or quaternized salts of dialkylaminoethyl methacrylate (MADAME).

12. The method of claim 1 , wherein a content of cationic monomer represents between 25% by weight and 99.9% by weight relative to the weight of the cationic polymer.

13. The method of claim 12 , wherein a content of cationic monomer represents between 50% by weight and 99.5% by weight relative to the weight of the cationic polymer.

14. The method of claim 1 , wherein the cationic polymer is crosslinked in the presence of a crosslinking agent selected from the group consisting of: methylenebisacrylamide (MBA), ethylene glycol diacrylate, polyethylene glycol dimethacrylate, diacrylamide, cyanomethyl acrylate, vinyloxyethyl acrylate or methacrylate, triallylamine, formaldehyde, glyoxal, compounds of glycidyl ether type, epoxies, and mixtures of these compounds.

15. The method of claim 14 , wherein the cationic polymer is crosslinked in the presence of a transfer agent selected from the group consisting of isopropyl alcohol, sodium hypophosphite, mercaptoethanol and mixtures of these compounds.

16. The method of claim 1 , wherein the cationic polymer is obtained by inverse emulsion polymerization.

17. The method of claim 1 , wherein the cationic polymer is in the form of an inverse emulsion comprising an oily phase, an aqueous phase, at least one water-in-oil (W/O) emulsifier, at least one oil-in-water (O/W) emulsifier and from 20% to 60% by weight of said cationic polymer.

18. The method of claim 1 , wherein the cationic polymer is obtained by polymerization:

of chloromethylated dimethylaminoethyl methacrylate;

of acrylamide; and

of ethoxylated behenyl methacrylate (EO 25).

19. The method of claim 1 , wherein the cationic polymer is obtained by polymerization:

of chloromethylated dimethylaminoethyl methacrylate;

of acrylamide; and

of ethoxylated cetyl methacrylate (EO 25).

20. The method of claim 1 , wherein a content of thickener represents 0.05% to 10% relative to the weight of the softening composition.