Parylene conformal coatings are used in many different industries. With their hardness, chemical inertness and ability to perfectly coat any surface, they have expanded well beyond their original military and aerospace applications. Whether it's a protective coating for an LED or a protective shell around a coronary artery stent, the compound is found in places where you might not expect to find it.
Parylene Coating Blog by Diamond-MT
From front to back, LEDs are improved by conformal coatings. Whether the coating is improving the LED's color accuracy, protecting it from damage or keeping the electronics functioning well, conformal coating of LED electronics extends the suitability of LED technology. Here are the top six ways that conformal coating and LEDs go well together
For all of Parylene's strengths, it has one key drawback—Parylene's resistance to ultraviolet (UV) radiation is limited. Most formulations of Parylene gradually yellow when exposed to the kind of UV light that's produced by the sun. While this isn't a problem when Parylene gets used to conformally coat a printed circuit board that's sealed in a box, it can be a problem when a display made of Parylene-coated LEDs is installed outdoors.
Parylene's benefits as a conformal coating are well known. It resists heat, cold, moisture, and pressure; salt spray, electricity, and solvents can't permeate it. And while these attributes of parylene contribute to the conformal coating's appeal, they also present distinct challenges, particularly in regards to parylene removal, rework, and repair.
The quality of a conformal coating job is directly related to the cleanliness of the substrate that is being coated. Clean substrates coat well, and contaminated ones don't. The only way to manage the problem is to inspect and clean the board or other item before applying the coating -- once it's coated, it's essentially too late.
More and more, cars aren't just made of steel, aluminum, plastic and silicon. Parylene is becoming one of the most useful tools in an automaker's arsenal. From protecting internal sensors and circuit boards to keeping LED indicator lights bright and color-accurate, Parylene conformal coatings are an important part of protecting today's sensitive automotive electronics.
It is imperative to obtain proper adhesion of the coating to the substrate in order to truly reap the benefits of parylene conformal coating. Poor parylene adhesion, after all, can negate some of parylene's most-prized properties, including corrosion resistance, chemical resistance, moisture resistance, and dielectric strength. So, it's in an engineer's best interest to understand the importance of parylene adhesion and how to obtain it.
Coronary stents are tubular medical implants that serve as a scaffold to open clogged or narrowed arteries in an effort to increase blood flow and reduce the potential for adverse cardiac events such as heart attacks. And providing critical support to these support structures is parylene conformal coating.