Patent ID: 8124578

Claim:
A delivery system in the form of a dynamic mixture obtainable by reacting: i) at least one hydrazine derivative of formula wherein R 1 represents a hydrogen atom, a C 1 to C 5 alkyl group or a phenyl group optionally substituted by up to three R 3 groups; R 3 represents a group selected from the group consisting of OR, NR 2 , SO 3 R, C 1-4 alkyl group and COOR, R representing a hydrogen atom, a C 1 to C 10 alkyl or polyethylene- or polypropylene-glycol group, a phenyl group or a C 6 to C 9 alkylaryl group; A represents a functional group selected from the group consisting of C═O, SO 2 , C═S and C═NR; and m is 0 or 1; n is 1, 2, 3 or 4; and R 2 represents a mono-, di-, tri- or tetra-radical from a C 1 to C 18 linear, branched or cyclic hydrocarbon group optionally comprising one, two, or three nitrogen or oxygen atoms, or from a phenyl group, or from a C 4-5 hetero-aromatic group, the R 2 being optionally substituted by up to three R 3 groups; with ii) at least one volatile perfuming ingredient comprising an active aldehyde or ketone having a molecular weight of between 80 and 230 g/mol; with the reacting conducted in a water-containing medium to reversibly form a hydrazone derivative.