Polyurethane, as known as urethane conformal coating
Advantages
- Good moisture, temperature, and dielectric characteristics
- High level of chemical resistance
- Polyurethanes can be soldered during rework
Disadvantages
- Re-work can prove difficult and costly
- For repair or replace a component, a special stripper compound must be used (need properly cleaned)
- The coating may develop a brownish residue that only impacts its appearance.
Categories
- 1 component: Even though single-component polyurethanes are simple to apply, they may need 3-10 days at room temperature to fully cure.
- In contrast, two-component formulations attain their optimal properties at high temperatures within 1-3 hours, but their usable lifespan ranges from 30 minutes to 3 hours.