Methods for dyeing hair keratin fibers comprising the application of a composition comprising a (poly)carbodiimide compound and a colorant and the application of a composition comprising an acid
By using a composition containing (poly)carbodiimide compounds and acids, the problem of color coatings being unable to withstand shampoo washing and external stress in existing dyeing methods is solved, achieving a uniform and long-lasting coloring effect on the hair.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- LOREAL SA
- Filing Date
- 2024-12-20
- Publication Date
- 2026-06-12
AI Technical Summary
Existing dyeing methods produce color coatings on hair that are not resistant to shampoo washing and external stresses such as brushing and friction, making it difficult to achieve a uniform and long-lasting coloring effect.
A composition comprising a (poly)carbodiimide compound and selected from pigments, direct dyes and mixtures thereof, combined with a composition comprising an acid, is used to form a uniform colored coating by applying these compositions to hair keratin fibers, wherein the pH of the acid is less than or equal to 6.
A uniform color coating is achieved on the hair, improving its resistance to shampoo washing and external stress, and ensuring the longevity of the coloring effect.
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Abstract
Citation Information
Patent Citations
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