419E – Premium Acrylic Conformal PCB Coating

For most electronic components, the main issue with their endurance is their direct environment. Notably, moisture and dust can corrode metals or create paths to shorting. Acrylic coatings provide circuits with a protective layer against these hazards so the circuit can maintain function and endure. Acrylics are user-friendly with short curing times, requiring no special equipment.

Acrylics are a common type of coating since they are so easy to use. The coating cures by drying and reaches full properties at room temperature. The coating contains a dye that makes it easy to inspect coverage under black lamp. Its low odor is ideal when using the coating within a confined space.

The cured coating has many key electrical features such as a high dielectric strength and high insulation resistance. The coating resists moisture and salt spray but is prone to attack from solvents like acetone or alcohols. Acrylics perform well in the right climate but cannot withstand harsh exposure to chemicals. Ensure the direct environment of the coating does not contain chemicals that could degrade it over time.

Acrylics are single component materials that make for easy conformal coating application. Most users opt to spray the coating for improved coverage and finish but there are many options for your coating process. For touch ups and light repair, you can brush apply the coating. Others may want to dip coat since this method is easy and requires little skill or equipment.

Users may need to apply special masking to certain electronic components to prevent malfunction. Since the coating is electrically insulating, masking must occur over male contact pins. This measure ensures the pins remain conductive without current impedance. Removing coating in keep-out areas is simple with use of any solvent.   

For high volume applications, users can thin out the coating and dispense via automated spray equipment. This method ensures high precision and does not require users to mask parts of the board. The 419E works on major equipment supplier platforms, giving consistent film thickness and sharp edge coverage.

The 419E received qualification as a conformal coating per the IPC-CC-830C standard. This standard replaces MIL-STD-46058C for conformal coating compliance. The standard covers a range of functions the coating must comply to ensure its fitness for use. 

The 419E is also compliant to the UL746E standard as a conformal coating. This standard ensures the coating withstands its dielectric performance after prolonged exposure to harsh stresses. These stresses include exposure to heat, humidity and thermal cycling. The test measures whether the coating withstands high voltage shocks without breakdown.

Included in both standards is testing for flame retardance. The IPC standard measures flame spread on a coated plastic strip while the UL standard checks for compliance per UL94 testing. In the UL94 test, the coating is applied over brominated plastic strips on both sides of the strip. The strip is mounted in a clamp vertically and set on fire.

The test measures whether the coated strip extinguishes itself within a given timeframe, thus ensuring fire will not spread. The 419E attained the highest flame rating for this test of V-0. The results mean an ignited strip coated with 419E will self-extinguish within 10 seconds if set on fire. The result pertains to a brominated FR4 substrate and does not mean the designation applies to other substrates.   

This PCB conformal coating is a promising option for PCB moisture protection. The conformal coating material protects against humidity, condensation, corrosion, fungus, dirt and dust. The coating protects from mechanical and thermal stresses like thermal shock, short circuits, high-voltage arcing, and static discharge.

This product is also available with other application methods in mind, like spray and pen packaging. These options are turnkey, ideal for small runs or designers making a prototype. Take note that the IPC and UL designations apply to the different packaging options. Aerosol makes spray application economical without the need for advanced equipment while pens are ideal solutions for touchups.

For higher temperature applications, we have a silicone/acrylic hybrid conformal coating, 422B. For more chemically resistance, try our polyurethane, 4223F. For high chemical resistance and fast cure response, consider our UV-curable option 4200UV.