Conformal Coating (Silicone Type) (Dow-Corning 1-2577 ´ëġǰ)
DESCRIPTION
RX-2577 conformal coating is a transparent silicone resin that offers good dielectric properties at both high and low frequencies and better thermal shock resistance than previously available silicone resins. It also has high resistance to moisture and excellent light transmission capabilities for solar applications.
The cured coating exhibits good weatherability and resistance to ultraviolet light. Other features include:
• Good electrical properties when cured
• Ease of application by spraying, dipping, brushing or flow coating
• Choice of room-temperature cure or heat cure
• Flame resistance
• Electrical (for coating printed-circuit-board assemblies)
• Flexibility over a wide temperature range from -65 to 200 C (-85 to 390 F)
• Easy repairability
• Contains ultraviolet indicator for ease in inspection under a black light
• Now available in convenient aerosol package
USES
RX-2577 conformal coating is used as a protective coating for rigid and flexible circuit boards and thick film circuitry, and for impregnating porous substances such as ceramics to improve moisture resistance.
HOW TO USE
Surface Preparation
For best adhesion, the surface to be coated with CHEMSOL RX-2577 conformal coating should be clean
and dry prior to application. RX-2577 conformal coating has excellent adhesion on clean boards under most conditions.
Application
RX-2577 conformal coating can be applied by spraying, dipping, brushing or flow coating.
For low-volume spray applications using a hand-held spray gun, dilution to 40 percent solids using dry aromatic
solvents, such as xylene or toluene, or dry 1 ,1, 1 -trichloroethane is recommended. For automated spray equipment, dilution to 50 percent solids using PMA (propylene glycol methyl ether acetate) is recommended.
Mixtures of PMA and RX-2577 conformal coati.ng should be used within 5 days of mixing.
One dip coat of RX-2577 conformal coating typically produces a film thickness of 5 to 8 mils. Thinner coatings can be achieved by diluting RX-2577 conformal coating with dry xylene, toluene or 1,1,1-trichloroethane. Figure I provides guidelines for dilution to achieve a desired coating thickness. Recommended withdrawal speed is approximately 12 inches per minute. For aerosol application, hold the can a distance of 4 to 8 inches from the substrate to be coated. Spray in a slightly overlapping pattern until the substrate is completely coated. Turn 90 degrees and repeat the spray pattern. Resultant coating thickness is approximately 1 mil (0.001 inch) per sequence.
Contact Point:
E-mail: kmb3d@hanmail.net (010-5522-8588)
TEL: 054-443-9497
FAX: 054-443-9498
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