If coating drying time is holding up a PCB or metal parts line, a UV-curable coating can cure in seconds under a UV lamp instead of air-drying. Micron 3608 Protektor PolyCoat UV is a UV-curable polyurethane photopolymer coating whose page says it cures instantly under a medium-pressure mercury vapour UV lamp, is solvent-free, and is for PCBs, metal tools, fixtures, sheet metals and machined parts. It needs a UV lamp line with operator shielding. Without a lamp, an air-drying acrylic such as Micron 3100 is the alternative.
Why it happens
- Solvent-based coatings need time to dry. An air-drying acrylic such as 3100 takes about 30 minutes to be dry to touch, so parts queue up or need racks and space.
You will see drying time becoming the line bottleneck, and sometimes concerns about solvent emissions in the coating area.
How to fix it
- High-throughput line with UV lamp curing: Micron 3608 Protektor PolyCoat UV, 5 L. Its page describes a transparent, glossy film, cross-hatch adhesion passed (ASTM D3359), resistance to wear, abrasion and chemicals, and a VOC-compliant, solvent-free formula. It says the cured surface is ready for handling immediately, with full chemical resistance developing within 24 hours.
- No UV lamp available: Micron 3100 Protektor Conformal Coating, an acrylic that air-dries to touch in about 30 minutes.
From the 3608 page, in outline:
- Surface must be clean, dry and free from oil, dust or oxidation. Use a suitable degreaser or solvent wipe.
- Apply by spray, dip or roller, uniformly. The page gives a recommended wet film thickness; follow it and the TDS.
- Cure under a medium-pressure mercury vapour UV lamp. The page states the lamp power, curing distance and line speed; set your line to the TDS values.
- Make sure UV safety shields are in place to protect operators during curing.
Plan the line before buying: lamp, conveyor, shielding and ventilation all need to be in place.
Questions to answer before switching:
- Do you already have a medium-pressure mercury UV lamp and conveyor, or does one need to be bought and installed?
- Can every coated surface see the lamp, or are there tall components and recesses that will be in shadow?
- Is there space for UV shielding around the curing zone?
- Will you spray, dip or roll, and does your applicator suit the coating's viscosity?
What to avoid
- 3608 requires a medium-pressure mercury UV lamp. It will not cure properly without one.
- Operators need UV safety shields during curing, as the page states.
- Avoid skin and eye contact; use appropriate PPE. Do not use in confined spaces without adequate ventilation.
- Store 3608 in a cool, dark, dry place away from sunlight and ignition sources.
- The 3100 aerosol propellant is flammable (stated): coat unpowered boards, ventilate, and keep away from ignition.
When to ask an expert
Ask Micron technical about:
- lamp selection, conveyor speed and line layout;
- whether your parts' shapes leave shadowed areas the UV light cannot reach;
- matching the coating to a customer specification.
FAQ
What does UV-cured mean?
The coating hardens when exposed to a UV lamp, rather than by solvent evaporating. That is why it can be handled straight after curing.
Is 3608 the same as the UV-traceable coating?
No. 3608 is UV-cured. 3110 Protektor Conformal Coating UV is UV-traceable: it glows under UV light for inspection. They are different products for different jobs.
Can I use 3608 on metal parts as well as PCBs?
Yes. Its page lists PCBs, metal tools, fixtures, sheet metals and machined parts.
What happens to areas the lamp cannot reach?
UV coatings need light to cure, so shadowed areas under tall components or in recesses may stay uncured. Discuss part geometry with Micron technical before switching.
Does 3608 contain solvent?
Its page describes it as VOC-compliant and solvent-free.
See the product: Micron 3608 Protektor PolyCoat UV. Related: 3100 Protektor Conformal Coating. More electronics fixes: electronics hub.