Acrylic Coating | MS-467C
Miller-Stephenson’s Acrylic Coating is a non-flammable, tough, fast drying, abrasion resistant conformal coating providing protection against caustics and corrosives. The methacrylate copolymer resin offers excellent resistance to water, alcohol, dilute acids & alkalis, chemical fumes and corrosive or oxidizing environments. It offers excellent weatherability and superior abrasion resistance. The resin water-white in color and transparency, with high gloss and hardness which is solderable for ease of repair.
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.
Acrylic Conformal Coatings are 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. It also provides a barrier to air-borne contaminants from the operating environment, such as salt-spray, thus preventing corrosion. Some typical application examples include high-reliability defense, automotive and aerospace, where coatings are used to protect against various combinations of moisture, aggressive chemicals and vapours, salt sprays, large temperature variations, mechanical vibration, and even organic attack (e.g. fungus). The protective nature of conformal coatings also means that they not only protect, but also serve to enhance product reliability and thereby reduce the potential cost and damaging effects of early field failures.
The recommendation made here with and the information set forth with respect to the performance or use of our products are believed, but not warranted to be accurate. The products discussed are sold without warranty, as to fitness or performance, express or implied and upon condition that purchasers shall make their own test to determine suitability of such products for their particular purposes. Likewise, statements concerning the possible uses of our products are not intended as recommendations to use our products in the infringement of any patent.