Release coating composition and release sheet

A release coating composition comprising compound (A), compound (B) and diluent (C), wherein

• compound (A) is an alkyl addition compound which is a product from an additive reaction between a polyamine compound (a1) and a monoisocyanate compound (a2), said polyamine compound (a1) having at least two active hydrogen-containing amino groups per one molecule and being selected from the group consisting of polyalkyleneimines, polyalkylenepolyamines, polyvinylamines, polyallylamines and modified compounds of polyvinylamine or polyallylamine using as a copolymerizable monomer at least one selected from the group consisting of olefins, (meth)acrylamide, N,N-dimethyl (meth)acrylamide, unsaturated carboxylic acids, esters or anhydrides thereof, vinyl sulfonic acid, dimethylaminoethyl (meth)acrylate, vinylimidazole, vinylpyridine and vinylsuccinimide, and said monoisocyanate compound (a2) being an alkyl monoisocyanate having an alkyl group of 8 or more in carbon number;
• compound (B) has, per one molecule, at least two functional groups capable of reacting with an active hydrogen of the amino group, and is at least one member selected from the group consisting of a polyvalent isocyanate compound having at least two isocyanate groups, a polyvalent epoxy compound having at least two epoxy groups, a polyvalent (meth)acryloyl compound having at least two (meth)acryloyl groups, a polyvalent carbonyl compound having at least two carbonyl groups, a polyvalent active ester compound having at least two active ester groups, a polyvalent methylol compound having at least two methylol groups, and a polyvalent aziridinyl compound having at least two aziridinyl groups;
• and
• the diluent (C) is at least one selected from the group consisting of an organic solvent and water.