Other applications Covestro Desmodur N3390 BA/SN HDI trimer curing agent standard light-resistant curing agent Type aliphatic polyisocyanate (hexamethylene diisocyanate trimer) Form of Supply about90%Butyl ... 11/15117Covestro Desmodur N3390 BA/SN HDI trimer curing agent standard light-resistant curing agent