Fecha de publicación: -- Fuente: WIPO "tomato" Ortho-phthaldehyde is introduced as a versatile moiety to imbue ultraviolet-absorbing or visible chromophore compounds bearing this moiety with the capability to remain locally retained in the epidermis for days to weeks by virtue of a safe, efficient, and reagent-free reaction that bonds the ortho-phthalaldehyde moiety covalently to endogenous proteins in the stratum corneum of skin tissue by forming a phthalimidine linkage with primary aliphatic amines such as lysine and N-terminal residues, when applied topically on human or other mammalian skin from a suitable liquid, gel, or emulsion containing the ortho-phthalaldehyde compound with cosmetically acceptable alcohols, oils, and modifiers.