HumiSeal®️ UV50 is a single-component, high solids, dual-cure acrylated polyurethane conformal coating specifically developed for the following purposes:
• Cures tack-free using microwave or arc UV light
• Has a viscosity suitable for use with selective coating equipment
• Features a secondary curing mechanism that fully cures unexposed areas within 7 days under ambient conditions*
• Fluoresces under UV light to enable coating inspection and can be applied with all selective coating equipment
• Offers higher flexibility compared to other UV-curable conformal coatings, providing better adhesion and performance in thermal cycling tests
• Provides excellent chemical and moisture resistance
*This duration may be reduced at higher temperature or humidity levels.
It is non-flammable, contains no volatile organic compounds (VOC) or solvents, and is compliant with RoHS Directive 2015/863.
Properties of HumiSeal®️ UV50:
Density: 1.0 to 1.1 g/cm³
Minimum Solids Content: 95%
Viscosity: 300 to 450 centipoise
Recommended coating thickness: 25–130 microns
Recommended UV curing: See curing section below
Shelf life at room temperature: 12 months
Hardness: A88 / D34
Thermal shock (50 cycles according to MIL-I-46058C): -65°C to 125°C
Flammability: UL-94 V-0
Cleaning:
Alcohol-free solvents should be used to clean equipment and remove uncured material. The use of HumiSeal®️ Thinner 521 or Thinner 521EU is recommended.
Curing:
HumiSeal®️ UV50 is a highly cross-linked coating material. To achieve maximum cross-link density, the product must be exposed to the correct spectral irradiation. HumiSeal has modeled the performance of UV50 using arc and microwave-based UV curing equipment. The table below summarizes the dosage and irradiation levels required to eliminate tackiness of HumiSeal®️ UV50 after UV exposure with both types of equipment. Minimum values should provide a tack-free surface. The maximum recommendations represent the highest values tested by HumiSeal. Curing recommendations may change as curing technologies evolve.
| | Dose J/cm2 * | Irradiance W/cm2 * |
|---|
| | UVA | UVB | UVC | UVA | UVB | UVC |
|---|
| Min | Arc System |
1.5 |
1.5 |
0.40 |
0.50 |
0.50 |
0.10 |
|---|
| Min | Microwave System |
2.0 |
2.0 |
0.40 |
0.70 |
0.70 |
0.15 |
|---|
| Max | Arc System |
2.8 |
2.7 |
0.80 |
0.90 |
0.80 |
0.20 |
|---|
| Max | Microwave System |
3.0 |
3.0 |
0.60 |
1.15 |
1.15 |
0.24 |
|---|
*Values were measured using a Powerpuck II UV radiometer.
Rework
HumiSeal®️ UV50 is a highly cross-linked, UV-cured coating. The cured film exhibits a high level of environmental and chemical resistance and is more difficult to remove than conventional conformal coatings. Thermal displacement and mechanical abrasion are suitable options for reworking HumiSeal®️ UV50.
Storage:
Light-sensitive. The product should not be exposed to direct sunlight or full-spectrum fluorescent light. For maximum shelf life, store in tightly sealed opaque containers between 0°C and 25°C, away from excessive heat. Before use, allow the product to equilibrate at room temperature for 24 hours. It is a moisture-curing material, and care should be taken to protect process containers and partially filled containers from moisture. Partially filled containers should be purged with a dry, inert gas such as dry air, nitrogen, or argon before sealing; otherwise, premature polymerization may occur due to atmospheric moisture.
