When Not to Use Acrylic Conformal Coating

While acrylic conformal coating does have many benefits, it is not the best solution if an application will be exposed to solvents, needs to withstand high temperatures or requires coating hardness.

Solvent exposure

Acrylic conformal coating can be removed with a weaker solvent such as isopropyl alcohol or xylene. If the coating encounters even stronger solvents, it will not provide the protection that is needed. Other coatings, such as urethane or Parylene conformal coatings, offer better resistance to solvents than acrylics.

High temperature requirements

The max continuous operating temperature of one of the most popular acrylic coatings, HumiSeal^® 1B31, is 125ºC. Silicone conformal coating offers an operating temperature that can exceed 200ºC. For higher temperature requirements, silicone conformal coatings provide a level of protection that acrylics cannot match.

Coating hardness

For substrates that will face mechanical wear, acrylics are not the best solution. While they do have a better mechanical wear resistance than silicones, urethane and epoxy conformal coating offer superior mechanical properties.