Acrylic Conformal Coating
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. HumiSeal® 1B73 coating is MIL-I-46058C qualified, IPC-CC-830 and RoHS Directive 2002/95/EC compliant, and recognized under UL File Number E105698.
Application of HumiSeal® 1B73
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.
Depending on the complexity, density and configuration of components on the assembly, it may be necessary to reduce the viscosity of HumiSeal® 1B73 with HumiSeal® Thinner 73 in order to obtain a uniform film. Once optimum viscosity is determined, a controlled rate of immersion and withdrawal (5-15 cm/min) will further ensure even deposition of the coating and ultimately a uniform film. During the application, evaporation of solvent causes an increase in viscosity that should be adjusted by adding small amounts of HumiSeal® Thinner 73. Viscosity in the dip tank should be checked regularly, using a simple measuring device such as a Zahn or Ford viscosity cup.
HumiSeal® 1B73 can be sprayed using conventional spraying equipment. Spraying should be done in an environment with adequate ventilation so that the vapour and mist are carried away from the operator. The addition of HumiSeal® Thinner 73 is necessary to ensure a uniform spray pattern resulting in pinhole-free film. The amount of thinner and spray pressure will depend on the specific type of spray equipment used and operator technique. The recommended ratio of HumiSeal® 1B73 to HumiSeal® Thinner 73 is 1:1 by volume; however the ratio may need to be adjusted to obtain a uniform coating.
HumiSeal® 1B73 may be brushed with a small addition of HumiSeal® Thinner 73. Uniformity of the film depends on component density and operator's technique.
HumiSeal® 1B73 should be stored away from excessive heat or cold, in tightly closed containers. HumiSeal® products may be stored at temperatures of 0 to 35°C. Prior to use, allow the product to equilibrate for 24 hours at a room temperature of 18 to 32°C.
Application of HumiSeal® Conformal Coatings should be carried out in accordance with local and National Health and Safety regulations.
The solvents in HumiSeal® Conformal Coatings are flammable. Material should not be used in presence of open flame or sparks. Use only in well-ventilated areas to avoid inhalation of vapours or spray. Avoid contact with skin and eyes.
Consult MSDS/SDS prior to use.