Or relating to curing agents

A curative composition comprising a combination of adipic acid dihydrazide or isophthalic dihydrazide and a clathrate, said clathrate comprises a host component and a guest component, said guest component comprising at least one compound selected from the group consisting of a compound represented by formula:

• in which R1 represents a hydrogen atom, a C1-C10 alkyl group, an aryl group, an arylalkyl group, or a cyanoethyl group, and R2 to R4 each independently represent a hydrogen atom, a nitro group, a halogen atom, a C1-C20 alkyl group, a C1-C20 alkyl group substituted with a hydroxy group, an aryl group, an arylalkyl group, or a C1-C20 acyl group;
• and a part with a dashed line represents a single bond or a double bond, and diazabicycloalkanes (DBCA);
• and
• said host component comprising 4,4′-bis(4′-hydroxyphenyl) valeric acid (BHPVA) or 4,4-bis(p-hydroxyphenyl) propionic acid (BHPPA).