Humiseal 2A64 | Urethane Conformal Coating


Main features
  • Exceptional Electrical Insulation
  • Easy Quality Control
  • High environmental resistance

Product Description

HumiSeal® 2A64 is a two-component polyurethane conformal coating supplied as Parts A and B for general PCB applications. 

HumiSeal® 2A64 offers high solids and low viscosity, making it easy to apply by brushing, dipping, or spraying. The coating fluoresces under UV light to allow quick inspection and is qualified to MIL-I-46058C, compliant with IPC-CC-830 and RoHS Directive 2011/65/EU. 

Mixed it has a density of about 1.07 g/cm³, viscosity of 130 cP, and solids of 55% by weight. Recommended film thickness is 25–75 µm. It is dry-to-handle in about 15 minutes and reaches full properties after curing 3 hours at 76 °C. Electrical performance is strong, with dielectric breakdown of 3,500 V, insulation resistance of 4.5×10¹⁴ Ω, and moisture insulation resistance of 4.8×10¹⁰ Ω.

The product is mixed 1:1 by volume, has an 8-hour pot life, and should be allowed to settle 30 minutes after mixing. It withstands −65 °C to +125 °C in thermal shock testing and is self-extinguishing per MIL-I-46058C. Shelf life is 12 months when stored between 0–35 °C.

Target applications:

  • PCB assembly protection requiring thin, uniform coatings
  • Automotive and industrial control modules exposed to moisture and contaminants
  • High-reliability electronics needing strong dielectric and insulation resistance
  • Assemblies requiring UV inspection for quality control
  • Processes using brush, dip, or spray application
Product Family
HS-2A64  
5L Can

Catalog Product

Unlike other products we offer, the products listed on this page cannot currently be ordered directly from the website.
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Packaging
TDS, SDS & Technical documents

Technical Specifications

General Properties
Density (g) 1.07 g/cm3
Pot Life
Pot Life
Pot life is the amount of time it takes for the viscosity of a material to double (or quadruple for lower viscosity materials) in room temperature after a material is mixed.

It is closely related to work life but it is not application dependent, less precise and more of a general indication of how fast a system is going to cure.
 8 hours
Solids 55 %
Shelf Life
Shelf Life
Shelf life is the amount of time after manufacturing that a product is guaranteed to retain its properties.

It differs vastly per product and it is based on temperature and storage conditions.

The properties can be guaranteed for the temperature and time range indicated on the TDS since those are the ones tested to be the best for the product.
Shelf Life @ 25°C 365 days
Electrical Properties
Breakdown Voltage
Breakdown Voltage
Breakdown voltage is the minimum voltage necessary to force an insulator to conduct some amount of electricity.
It is the point at which a material ceases to be an insulator and becomes a resistor that  conducts electricity at some proportion of the total current. 

After dielectric breakdown, the material may or may not behave as an insulator any more because of the molecular structure alteration. The current flow tend to create a localised puncture that totally alters the dielectric properties of the material.

This electrical property is thickness dependent and is the maximum amount of voltage that a dielectric material can withstand before breaking down. The breakdown voltage is calculated by multiplying the dielectric strength of the material times the thickness of the film.
 3500 V
Thermal Properties
Coefficient of Thermal Expansion (CTE)
Coefficient of Thermal Expansion (CTE)
CTE (Coefficient of thermal expansion) is a material property that is indicative of the extent to which a material expands with a change in temperature. This can be a change in length, area or volume, depending on the material.

Knowing the CTE of the layers is helpful in analyzing stresses that might occur when a
system consists of an adhesive plus some other solid component.
Coefficient of Thermal Expansion (CTE) , α1
Coefficient of Thermal Expansion (CTE) , α1
CTE α1 (alpha 1) is the slope of the Coefficient of thermal expansion in a temperature range below the Glass transition temperature (Tg).

It explains how much a material will expand until it reaches Tg.
 82 ppm/°C
Coefficient of Thermal Expansion (CTE), α2
Coefficient of Thermal Expansion (CTE), α2
CTE α2 (alpha 2) is the slope of the Coefficient of thermal expansion in a temperature range above the Glass transition temperature (Tg).

It explains the extent to which a material will expand after it passes Tg.
 255 ppm/°C
Glass Transition Temperature (Tg)
Glass Transition Temperature (Tg)
The glass transition temperature for organic adhesives is a temperature region where the polymers change from glassy and brittle to soft and rubbery. Increasing the temperature further continues the softening process as the viscosity drops too. Temperatures between the glass transition temperature and below the decomposition point of the adhesive are the best region for bonding.

The glass-transition temperature Tg of a material characterizes the range of temperatures over which this glass transition occurs.
 12 °C

Additional Information

Frequently Asked Questions About HumiSeal® 2A64

What are typical applications for HumiSeal® 2A64?


HumiSeal® 2A64 is used for protecting printed circuit boards in high-reliability electronics requiring moisture, chemical, and electrical insulation.

  • Electronics manufacturing (PCB assembly)
  • Automotive control modules
  • Industrial electronics in harsh environments

Why choose HumiSeal® 2A64 over alternatives?


It combines high solids, low viscosity for easy application, UV inspection capability, and compliance with MIL-I-46058C, IPC-CC-830, and RoHS standards.

What is the shelf life of HumiSeal® 2A64?

12 months from date of manufacture when stored at 0°C to 35°C in tightly sealed containers.

How do I clean tools after applying HumiSeal® 2A64?

Use HumiSeal® Stripper 1072 or the recommended thinner immediately after use to prevent curing on tools.

What happens after shelf life?

Performance and application properties may degrade, risking incomplete curing or reduced protection.

How do I cure HumiSeal® 2A64?

Allow to dry to handle in 15 minutes, then cure for 3 hours at 76°C for optimum properties.

What thickness should I apply?

Apply at 25–75 microns for optimal performance.

How is it applied and removed?

Can be applied by brushing, dipping, or spraying with proper thinning; remove with HumiSeal® Stripper 1072.

What temperatures can it withstand?

Passes thermal shock from -65°C to +125°C.

Any safety or storage tips?

Store between 0°C and 35°C; keep away from flames, use in ventilated areas, avoid contact with skin and eyes.

What are the key material properties?

  • Appearance: Transparent, fluoresces under UV
  • Rheology: Low viscosity
  • Specific gravity: 1.07 ± 0.03 g/cm³
  • Tg: 12°C; Modulus: 4101 MPa @ -40°C; 2777 MPa @ 25°C; 2 MPa @ 80°C
  • Compliance: MIL-I-46058C, IPC-CC-830, RoHS

Is it compatible with metals and coatings?

Compatible with most PCB metals and coatings; verify compatibility when used over “no-clean” flux residues.

 

Learn More About HumiSeal® 2A64

HumiSeal® 2A64 is a high-solids, two-component polyurethane coating that provides durable PCB protection, excellent dielectric insulation, and fast, UV-inspectable application.

Key Features at a Glance

  • ✔ High solids, low viscosity
  • ✔ Fast dry to handle
  • ✔ Moisture & fungus resistant
Product Benefits

Versatile Application Methods 🧰

Application Methods 🧰

Mix Parts A and B 1:1 by volume until homogenous (avoid vigorous mixing). Apply by:

  • Brush: For precise applications and touch-ups
  • Spray: With conventional spray equipment and recommended thinner
  • Dip: For complete coverage of assemblies, adjusting viscosity as needed

Curing: 3 hrs at 76°C for full properties. Dry to handle in 15 minutes.

Application Compatibility ✔

Suitable for a variety of PCB types and electronic assemblies, including:

  • Mission-critical electronics
  • Moisture-sensitive devices
  • High-vibration environments

UV tracer allows fast inspection under UV light to confirm coverage.

Repairable and Reworkable 🔁

Coated assemblies can be reworked using HumiSeal® Stripper 1072 or mechanical removal methods.

Reliable Across Environments 🌍

Performs consistently under -65°C to +125°C thermal shock conditions, providing moisture, fungus, and dielectric protection in harsh environments.

Compliance You Can Trust ✅

HumiSeal® 2A64 meets or exceeds key industry standards:

  • MIL-I-46058C Qualified
  • IPC-CC-830 Compliant
  • RoHS Directive 2011/65/EU
  • Fungus resistance per ASTM G21
  • Self-extinguishing flammability
  • High insulation resistance