Brightening and/or dyeing agent with urea derivatives

摘要

Urea, thiourea or guanidine derivatives (I) are used to improve the lightening action of hair bleaches or lightening dyes. Urea, thiourea or guanidine derivatives of formula R3>R4>N-CX-NR1>R2> (I) are used to improve the lightening action of hair bleaches or lightening dyes. X : O, S or NR5>; R1>-R5>H or optionally substituted aryl, 1-24C alkyl or 2-24C alkenyl. An independent claim is also included for a product for dyeing and/or lightening keratin fibers, especially human hair, comprising 0.01-10 wt.% (I).