Silicones 2A53
Model No: 2A53

HumiSeal® 2A53 is a two component epoxy conformal coating supplied as Parts A and B, suitable for general printed circuit boards and applications where exceptional resistance to solvents or other chemicals is required. HumiSeal® 2A53 fluoresces under UV light for inspection purposes.

 Product Enquiry

Application of HumiSeal® 2A53

Cleanliness of the substrate is of extreme importance for the successful application of a conformal coating. Surfaces must be free of moisture, dirt, wax, grease, flux residues and all other contaminants. Contamination under the coating could cause problems that may lead to assembly failures. Mixing ratio of Part A to Part B is 1:1 by volume. Prior to application, HumiSeal® 2A53 Parts A and B should be thoroughly mixed until a homogenous blend is achieved. Vigorous mixing is not recommended. The mixed coating should be allowed to settle for 30 minutes prior to use, so that any air bubbles formed during blending.


Product Specification

Density, per ASTM D1475

0.93 ± 0.03 g/cm³


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

54 ± 5 %

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

350 ± 150 centipoise


455 grams/litre

Recommended Coating Thickness

25 - 75 microns

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

5 hrs

Time Required to Reach Optimum Properties

7 days

Optional Curing Conditions to Reach Optimum Properties

2 hrs @ 93°C

Recommended Thinner

HumiSeal® Thinner 535

Pot Life at Room Temperature

24 hours

Shelf Life at Room Temperature, DOM

12 months

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

-65°C to 125°C

Glass Transition Temperature – DSC


Coefficient of Thermal Expansion – TMA

56 ppm/°C

Modulus – DMA

32.2 MPa

Flammability, per MIL-I-46058C


Dielectric Withstand Voltage, per MIL-I-46058C

>1500 volts

Dielectric Breakdown Voltage, per ASTM D 149

8000 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

2.0 x 1014 ohms (200TΩ)

Moisture Insulation Resistance, per MIL-I-46058C

2.8 x 1010 ohms (28GΩ)

Fungus Resistance, per ASTM G21


Resistance to Chemicals



Other Products in this Category