Blocked isocyanates and polyurethane prepolymers enable 1K polyurethane systems with lower free isocyanates, improved storage stability, and reduced moisture sensitivity. In coatings, they are widely applied in electro-deposition, electrostatic spray, powder coatings, wire insulation, and coil coatings, delivering heat-curable performance with fewer health risks. In adhesives and sealants, blocked prepolymers support epoxy-amine adhesives, hotmelts, pressure-sensitive adhesives, and sealants.

Blocking agents such as MEKO, alcohols, ɛ-caprolactam, amides, imidazoles, and pyrazoles define cure profile and final properties. With health concerns over traditional phenols, demand is growing for safer, cost-effective alternatives.