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Parylene Coating Blog by Diamond-MT
Conformal coatings frequently play a critical role in protecting medical, electronics, defense, aerospace, LED, and automotive applications from contaminants and other potentially hazardous substances. But they're not infallible.
Maintaining proper thickness for silicone conformal coating is critical because it is applied very thick compared to other conformal coatings. If a coating is applied too thick, it may create excessive stresses on solder joints and components (particularly glass-bodied components). If a coating is applied too thin, it may not reach the optimum properties described on the Technical Data Sheet. For this reason, the IPC created the J-STD-001 to regulate and standardize the thickness that coatings are applied at. For silicones, the J-STD-001 calls out 0.00197 to 0.00827 in. Our operators strive to hit between .002” and .008” for silicone applications.
Last week, we discussed what the causes of bubbles in conformal coating are. Now, let’s go through the various ways to remedy the bubbles.
Stripping or removal of unwanted conformal coating from a printed circuit board (PCB) can be a relatively simple process or a very messy difficult job. It does depend on several factors including the type of conformal coating you need to remove, where the coating is found and the type of components on the board.
Silicone conformal coating is becoming an increasingly popular choice for conformal coating applications. Because of its high temperature capabilities, moisture protection, and ease of application/rework, people are strongly considering silicone coatings for their projects.
One potential issue with considering selective conformal coating with a robotic conformal coating system is misaligned components on the PCB which can potentially damage the spray heads which are moving along a set pattern on the board and the components themselves be damaged as they travel. Spray heads are one of the most critical parts on the spray robot. Repairing damage can get costly.
Tags: acrylic conformal coating, Diamond-MT, conformal coating, conformal coating equipment, HumiSeal 1B31, conformal coating methods, conformal coating service, conformal coating removal, conformal coating rework