Polyurethane Delayed Action Catalysts in Microelectronic Encapsulation Materials: A Comprehensive Review Abstract: Microelectronic encapsulation plays a crucial role in protecting sensitive electronic components from environmental stressors and ensuring long-term device reliability. Polyurethane (PU) resins are increasingly employed as encapsulation materials due to their tunable properties, excellent adhesion, and cost-effectiveness. However, the rapid reaction kinetics of...