Cosmetic or dermatological composition comprising a merocyanine and a gamma-butyrolactone and/or a gamma-butyrolactam

A method for solubilizing a merocyanine corresponding to the following formula (3) and also their geometrical isomer forms:

• in which:
• A is —O— or —NH—;
• R is a C1-C22 alkyl group, a C2-C22 alkenyl group, a C2-C22 alkynyl group, a C3-C22 cycloalkyl group or a C3-C22 cycloalkenyl group, it being possible for said groups to be interrupted by one or more O in the fatty phase and/or in the aqueous phase of a composition, which comprises including in the composition at least one compound chosen from gamma-butyrolactones and gamma-butyrolactams of the formula as defined below, and also the organic or mineral acid or base salts thereof, and the solvates thereof such as hydrates:
• in which:
• X represents an oxygen atom, a sulfur atom or a nitrogen atom bearing an R4 radical, with R4 representing a hydrogen atom or a linear or branched C1-C6,
• R1, R2 and R3 represent, independently of one another:
• a hydrogen atom,
• a linear or branched C1-C6 alkyl radical, or
• an —[O]n—C(O)—[O]p—R5 radical, where:
• n is equal to 0 or 1, p is equal to 0 or 1, with n+p equal to 1 or 2,
• R5 represents a hydrogen atom or a linear or branched C1-C6 alkyl radical.