Acrylics Conformal coating 1B73
Model No: 1B73

HumiSeal® 1B73 is a single component, fast drying, acrylic conformal coating intended for use on printed circuit assemblies. HumiSeal® 1B73 demonstrates excellent flexibility and electrical properties, fluoresces under UV light for ease of inspection and is easily repaired.

 Product Enquiry

HumiSeal® 1B73 conformal coating is:

  • an acrylic chemistry
  • fast drying
  • single component
  • recognized under UL File Number E105698
  • used in combination with Thinner 73


HumiSeal® 1B73 conformal coating has:

  • excellent moisture and environmental protection for printed circuit assemblies
  • excellent flexibility
  • fluorescence under UV light for ease of inspection
  • rework ability with ease
  • MIL-I-46058C qualification
  • IPC-CC-830 compliance
  • RoHS Directive 2002/95/EC compliance


Application of HumiSeal® 1B73 Conformal Coating

Conformal coatings can be successfully applied to substrates that have been cleaned prior to coating and also to substrates assembled with low residue “no clean” materials. Users should perform adequate testing to confirm compatibility between the conformal coating and their particular assembly materials, process conditions and cleanliness level.


Product Specification

Density, per ASTM D1475

0.92 ± 0.02 g/cm³

Solids Content, % by weight per Fed-Std-141, Meth. 4044

29.5 ± 2 %

Viscosity, per Fed-Std-141, Meth. 4287

250 ± 20 centipoise


661 grams/liter

Drying Time to Handle per Fed-Std-141, Meth. 4061

30 minutes

Recommended Coating Thickness

25 -75 microns

Recommended Curing Conditions

24 hrs @ RT or 2 hrs @ 76°C

Time Required to Reach Optimum Properties

7 days

Recommended Thinner

HumiSeal® Thinner 73

Recommended Stripper

HumiSeal® Stripper 1080, 1080A

Shelf Life at Room Temperature, DOM

24 months

Thermal Shock, 50 cycles per MIL-I-46058C

-65°C to 125°C

Coefficient of Thermal Expansion – TMA

67 ppm/°C

Glass Transition Temperature – DSC


Modulus – DMA

11.1 MPa

Flammability, per UL 94


Dielectric Withstand Voltage, per MIL-I-46058C

>1500 volts

Dielectric Breakdown Voltage, per ASTM D149

6300 volts

Dielectric Constant, at 1MHz and 25°C, per ASTM D150-98


Dissipation Factor, at 1MHz and 25°C, per ASTM D150-98


Insulation Resistance, per MIL-I-46058C

5.5 x 1014 ohms (550TΩ)

Moisture Insulation Resistance, per MIL-I-46058C

7.0 x 1010 ohms (70GΩ)

Fungus Resistance, per ASTM G21