Protective coating MS-477C

abrasion-resistantacrylicfor the aerospace industry

Miller-Stepheson Acrylic Conformal Coating MS-477C offers superior toughness and abrasion resistance, excellent dielectric properties, fungal resistance, and moisture and environmental protection. Our formulation is 100% non-flammable. Printed circuit boards covered with acrylic coatings are repairable. Simply heat the coating with a soldering iron to remove the components. 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. Printed circuit boards covered with acrylic conformal coatings are repairable. Simply heat the coating with a soldering iron to remove the components. Drying and curing of acrylic coating depends upon evaporation of the solvent. Air dry coated boards for 30 minutes at 77°F/25°C to remove solvents before curing in oven or applying additional coats. The recommended cure time is 45 minutes at 167°F/75°C. The alternate cure is 24 hours at 77°F/25°C. Acrylic coating will be tack-free in one hour, semi-hard in four hours, and fully cured in 24 hours. Deaeration is not recommended. MS-477C Acrylic Conformal Coating is probably the easiest coating to remove and repair. The coating can be removed completely or locally by using specifically designed stripping chemistries. The board can then be re-coated completely of just in area of the repair. By being electrically insulating, it maintains long-term surface insulation resistance (SIR) levels and thus ensures the operational integrity of the assembly.