| abstract |
A water-based polyurethane resin capable of imparting excellent rust resistance without performing a chromate treatment on a steel sheet / steel material surface, which has environmental problems. A diisocyanate such as tolylene diisocyanate, diphenylmethane diisocyanate, hydrogenated diphenylmethane diisocyanate or the like is used alone or in combination as an organic isocyanate component, and 1,4-cyclohexanedimethanol and a glycol-based polyether are used as a polyol component. A water-based polyurethane resin for rust prevention, which is obtained by emulsifying a prepolymer obtained by reacting a diol or a triol containing a carboxyl group with a chain extender and which is not subjected to chromium-based treatment and used for steel sheets and steel materials. |