UV lamp mercury vs metal halide

Wed, 24 Jun 2026 07:50:06 +0800

On the floor, when you get color drift in pad or screen work, it’s almost never just the ink. It’s the UV spectral output being mismatched. If your photoinitiators are built to run on 365nm and the lamp is peaking at 385nm, the cross-linking kinetics shift. You end up with under-cure at the nip, then over-exposure that starts to bleach pigments. The payoff is metamerism and batches that don’t hit spec. What actually matters Mercury vapor lamps put strong energy around 365nm, with broad tails that run up into the visible. Metal halide lamps push and intensify peaks toward 385–405nm, adding more long-wave energy. In practice, that means different photoinitiator packages reach full conversion at different spectral doses. Measure it properly with a spectral radiometer: peak irradiance at the substrate, energy density in mJ/cm², and the lamp’s spectral curve as it ages. Reflector dichroic coatings and the quartz envelope shape what spectrum actually hits the ink. Swap in a reflector that’s off-target, and you can skew the very wavelengths your chemistry is counting on. Why this matters on pad and screen Pad and screen jobs run tight tolerances—opaque whites, fluorescents, fine halftones that can’t take inconsistency. When lamp output matches the ink’s photoinitiator window, cure stabilizes on the first pass. Dot gain stays predictable. Color stays predictable. And you stop throwing away work because the surface didn’t cure through. With spectral output that holds steady, you can lock your process windows, cut makeready, and run faster without chasing color shifts every shift. The details you live with Metal halide lamps can deliver more long-wave energy, which helps penetrate thicker ink layers, but they demand stable ballast and consistent arc gaps. Mercury lamps give you tighter 365nm performance, but they can age faster when you’re cycling on and off a lot. Make sure the lamp plays nicely with your press reflector geometry and the shutter duty cycle. Expect output to drop as the arc tube erodes. Schedule periodic spectral checks, and keep a running log of irradiance at the substrate plane so color stays consistent across the lamp’s life.

Metal on UV Curing Supply

UV lamp mercury vs metal halide