Long-lasting easy wash-off cosmetic compositions
View Patent ↗Cosmetic compositions are provided, which are capable of forming a cosmetic film on a human integument when applied thereto. Cosmetic compositions according to the invention typically include a cosmetically acceptable vehicle, optionally, one or more colorants, and a pH-dependent film-forming polymer of poly(methacrylic acid-co-methyl methacrylate) having a ratio of methacrylic acid to methyl methacrylate of about 1:1 to about 1:2, an acid value of from about 150 to about 350 mg KOH/g, and a weight average molar mass between about 100,000 and about 150,000 g/mol. The compositions are capable of forming an adherent film on the integument that is substantially resistant to removal by water at a first pH, but readily dispersible or soluble in water at a second pH higher than said first pH.
1. A method for forming a cosmetic film on a human integument comprising: applying to said human integument a cosmetic composition comprising a cosmetically acceptable vehicle, optionally, one or more colorants, and a pH-dependent film-forming polymer of poly(methacrylic acid-co-methyl methacrylate) with a ratio of methacrylic acid to methyl methacrylate of about 1:1 to about 1:2, an acid value of from about 150 to about 350 mg KOH/g, and a weight average molar mass between about 100,000 and about 150,000 g/mol, wherein said polymer is capable of forming an adherent film on a human integument that is resistant to removal by water at a first pH, but readily dispersible or soluble in water at a second pH higher than said first pH, with the proviso that said film forming polymer is not in the form of a microcapsule, wherein said cosmetic composition is a mascara.
2. A method according to claim 1 , wherein said second pH is greater than about 5.5.
3. A method according to claim 1 , wherein said second pH is greater than about 6.5.
4. A method according to claim 1 , wherein said second pH is greater than about 7.5.
5. A method according to claim 1 , wherein said ratio of methacrylic acid to methyl methacrylate is about 1:1.
6. A method according to claim 1 , wherein said ratio of methacrylic acid to methyl methacrylate is about 1:2.
7. A method according to claim 1 , wherein said acid value is from about 150 to about 200 mg KOH/g.
8. A method according to claim 1 , wherein said acid value is from about 300 to about 350 mg KOH/g.
9. A method according to claim 1 , further comprising contacting said cosmetic composition with soap and water to raise the pH of the human integument from the first pH to the second pH, thereby removing the cosmetic composition from the human integument.
10. A method according to claim 1 , wherein said cosmetic composition is a mascara.
11. A cosmetic composition comprising a cosmetically acceptable vehicle, optionally, one or more colorants, and a pH-dependent film-forming polymer of poly(methacrylic acid-co-methyl methacrylate) with a ratio of methacrylic acid to methyl methacrylate of about 1:1 to about 1:2, an acid value of from about 150 to about 350 mg KOH/g, and a weight average molar mass between about 100,000 and about 150,000 g/mol, wherein said polymer is capable of forming an adherent film on a human integument that is resistant to removal by water at a first pH, but readily dispersible or soluble in water at a second pH higher than said first pH, with the proviso that said film forming polymer is not in the form of a microcapsule, wherein said cosmetic composition is a mascara.
12. A composition according to claim 11 , wherein said second pH is greater than about 5.5.
13. A composition according to claim 11 , wherein said second pH is greater than about 6.5.
14. A composition according to claim 11 , wherein said second pH is greater than about 7.5.
15. A composition according to claim 11 , wherein said ratio of methacrylic acid to methyl methacrylate is about 1:1.
16. A composition according to claim 11 , wherein said ratio of methacrylic acid to methyl methacrylate is about 1:2.
17. A composition according to claim 11 , wherein said acid value is from about 150 to about 200 mg KOH/g.
18. A composition according to claim 11 , wherein said acid value is from about 300 to about 350 mg KOH/g.