Techspray offers SR, AR and UR conformal coating formulas for a wide variety engineering requirements including thermal, moisture & static resistance. All coatings are IPC-CC-830B and UL94 V-0 qualified.
Techspray offers a variety of conformal coating formulas for differing field or engineering requirements and is IPC CC 830B and UL94-0 Qualified or rated. Specifications generally depend on the type of protection needed: e.g., thermal, moisture, or static resistance.
Coatings contain Opti/Scan (except LED Coating) to allow quality control inspection of coverage and evenness of the coating on a PCB. A coated board can be passed under a standard, low-cost UV (short-wave black) light to fluoresce the coated areas. The brighter the glow, the thicker the coating.
Whether or not conformal coating is required depends on the environment the electronic device will operate in, the reliability requirement of the device, and the cost of failure, whether in dollars or human lives. Typical consumer devices are generally not coated because cost is one of the top driving factors, and a coating step certainly adds to that. Devices operating in harsh environments may require coating, and the type of stresses and contamination will point to the best option, whether that is acrylic resin (AR), silicone resin (SR), urethane resin (UR), or some other type of protection. Aviation, aerospace, and medical devices often require coating because of the mission critical nature of these applications.
Full cure is when it meets all the final specifications. There might be some out-gassing, but it will be as hard as it is going to be, and adhesion is as good as it gets. Tack-free is as the name suggests, not sticky so you can move it along the assembly process.
While conformal coatings can offer a moisture resistant layer of protection, most cannot be considered waterproof. Even if applied heavily, most coatings are semi-permeable, so allow some amount of moisture through. Conformal coating can, however, prevent current leakage or corrosion due to ambient moisture. To truly waterproof electronics, you either need gasketing to seal the electronics within the packaging or cover the electronics with a waterproof encapsulant or potting compound.
No, conformal coatings are non-conductive, or insulative. The job of conformal coating is to isolate the PCB or components from the environment and even components (i.e. high voltage or high heat) from the rest of the board. To do that properly, a coating must have electrically insulating properties with as high of a dielectric withstand voltage (or strength) as possible.
Every organization using hazardous chemicals within their facility has the responsibility to equip their facility and personnel to maintain exposure levels below the TLV. Personal monitoring badges can be used to measure exposure of a specific material. Then, depending on the threshold limit and the application, exposure can be controlled with PPE like masks, face shields, respirators, and even coveralls. If they don’t reduce exposure below the recommended limit, you will need to consider a special ventilation hood or even containment booth. As you can see, as the exposure limit gets down to a certain level, the equipment required to safely use the solvent can get impractical. At that point, your best option is to consider a safer alternative.
The dielectric strength is material intrinsic property and withstand voltage is surface property which depend on thickness of the material. They can be slightly different for thicker materials, but for conformal coating, the two numbers should be very close or the same. That is because we test coating at 3-5 mils thickness, calculate, then report the value per mil.