Coating reduces shielding costs for enclosures
APPLICOAT EC225 provides an order of magnitude better electrical shielding than nickel paints. The thickness is under half that of nickel, so the applied coating cost is significantly reduced.
Conductive paints are widely used for EMI / RFI shielding of plastic enclosures. They offer many advantages over alternative methods of shielding. these include: relatively short manufacturing lead-times; ability to coat selectively; suitability for low as well as high volume production; moderate to high levels of shielding and excellent adhesion to most plastics.
Paints can be made conductive by adding nickel, copper or silver particles to the resin.
Traditionally nickel paints were specified for low cost / low performance applications.
For high levels of shielding, silver is normally specified.
However these coatings are considerably more expensive than copper or nickel paints.
Applied Coating Technologies (ACT) has recently introduced a new coating, APPLICOAT EC225, based on paint containing silver-plated copper particles.
This coating costs less than nickel paint yet provides shielding performance comparable to silver paint.
To compare the applied thickness and sheet resistance of nickel, APPLICOAT EC225, and silver coatings: a nickel coating of 50-70 microns provides a sheet resistance (ohms/cm2 of 0.2-0.5 and 10-15 microns of silver, a sheet resistance of 0.03-0.05 ohms/cm2.
APPLICOAT EC225 of thickness 20-25mm provides a sheet reistance of 0.05-0.08 ohms/cm2 APPLICOAT EC225 provides an order of magnitude better shielding than nickel paints.
However as the applied thickness is less than half that of nickel, processing and material costs are reduced and hence the applied cost of the coating is significantly reduced.
APPLICOAT EC225 also offers other benefits; it is formulated using alcohol based solvents and hence has minimum impact on the intrinsic properties of the substrate.
ACT specialises in the application of shielding and decorative coatings onto plastic substrates.
The company also offers vacuum deposited and electroplated coatings for EMI / RFI Shielding.
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