Crosslinking agent for fibers or leather
A crosslinking agent for fibers or leather according to the present invention contains a blocked isocyanate which is obtained by blocking, by means of a blocking agent, an isocyanate group of a hydrophilic group-containing polyisocyanate that is a reaction product of a polyisocyanate and a hydrophilic group-containing active hydrogen compound. The blocking agent contains a secondary amine compound wherein: two carbon atoms are directly bonded to the nitrogen atom of a secondary amine; and at least one of the two carbon atoms is a tertiary carbon atom.