Principle of curing UV powder coating

Wood and wood composites Solid wood as well as particleboard and medium-density fiberboard (MDF) are suitable substrates for powder coating. They tend to emit volatiles such as entrapped air and moisture, and therefore require curing temperatures below 100°C (212°F) and preferably nof higher than 80°C (144°F). A typical curing procedure for MDF is in Table 7.8. 

Preassembled parts Preassembled parts may contain components made from heat-sensitive substrates (e.g., plastic inserts, wiring). In contrast to the conventional method, where individual components are coated prior to assembly to avoid heat damage, UV powder coating permits the manufacturer to fully assemble a part prior to coating. 

Large-mass parts Conventional coating of large-mass parts requires exceedingly long times in convection ovens. A considerable reduction of times required for cure is to melt the powder with IR and use fast UV-initiated free radical curing reactions. 

Process Variable Clear Type of Coating Pigmented Note 

Type of UV lamp Mercury Gallium-doped mercury Microwave or arc lamps 

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