hdi low viscosity covesro n3600   characterization : aliphatic polyisocyanate (low-viscosity hdi trimer). use as the hardener component for flexible, lightfast polyurethane coating systems. specification: property value unit of measurement method nco content 23.0 ± 0.5 % % m105-iso 11909 viscosity at 23 °c 1,200 ± 300 mpa·s m014-iso 3219/a.3 color value (hazen) ≤ 40 m017-en 1557...