Conformal coatings are applied in thin layers to printed circuit boards (PCBs) to provide environmental and mechanical protection against elements such as moisture, dust, chemicals, and extreme temperatures. Conformal coatings extend the useable life of a PCB by protecting against contaminants and preventing short circuits and corrosion. Selecting the right coating and method of application for a particular industry such as military/aerospace, industrial, automotive, etc. will also help extend the life of the PCB. Here is a quick roundup from several PCB coatings suppliers.
Cytec
Coatings for improved safety and environmental compliance
Cytec’s CONAP conformal coatings for PCB applications aim to provide specific focus on improved safety, environmental compliance and faster processing. The CONAP product family of acrylic and polyurethane conformal coatings provide humidity resistance, hydrolytic stability, and UL94 V0 fire rating. Qualified for military and IPC specifications, Cytec’s CONAP conformal coatings are designed for high reliability applications used aerospace, biomedical, electronics and automotive industries. Cytec can also formulate custom materials to meet specific performance and quality standards.
Dow Corning
Circuit protection in severe service environments
Dow Corning coatings are well suited to protect electronic circuitry in severe service environments, ranging from every day temperature and humidity extremes seen in consumer electronics, to the harsher automotive under-hood applications, up to the extremes demanded in military or industrial applications. Dow Corning aims to provide a variety of conformal coatings and processing options, including several environmentally friendly products, to protect circuitry against diverse operating conditions and applications. All conformal coatings contain a UV indicator enabling black light visualization of the coating.
Dymax
Light-curable coatings for streamlined manufacturing
Conformal coatings from Dymax are designed to cure quickly upon exposure to UV/visible light and aim to streamline manufacturing assembly processes. The goal of Dymax’s light-curable coatings is to increase throughput by eliminating time-consuming steps of traditional thermal-cure and room temperature-cure conformal coatings. They are electrically insulated so they can be applied over the entire PCB surface or in select areas to provide protection from service environments. Their solvent-free conformal coatings require no mixing and contain low VOCs to help improve worker safety and minimize environmental impact.
Henkel
Eco-friendly materials for harsh environments
Henkel’s conformal coating materials are well suited to protect electronic circuitry from a variety of adverse conditions such as thermal shock and moisture corrosion and aim to address long product life cycles in harsh marine, automotive, aerospace and consumer electronics applications. Henkel's product range of conductive, dielectric and other functional polymer thick film inks have been used to apply selective coatings on a variety of flexible and rigid substrates, via screen, flexographic and rotogravure printing methods. Henkel has migrated to solvent-free, low-VOC materials and processes and their conductive coatings and inks can be effectively dried or cured through heat or UV radiation.
Humiseal
Conformal coatings qualified to military and IPC standards
Humiseal aims to provide a wide variety of conformal coatings from all chemistries, including acrylics, urethanes and silicones, both water-based and UV-curable to protect electronic circuits from harsh environments for a wide variety of applications. HumiSeal’s formulations designed specifically for military and aerospace applications are tested against stringent performance criteria and are qualified to MIL-I-46058C and IPC-CC-830 standards. The goal of Humiseal’s wide range of coatings is not only protect, but also serve to enhance product reliability and thereby reduce the potential cost and damaging effects of early field failures. Humiseal can also create special formulations customized for a particular application.
Master Bond
Environmentally friendly PCB protection
Master Bond’s conformal coatings are designed to protect electronic circuitry against moisture, chemicals, abrasion, thermal cycling, elevated temperatures, mechanical shock, etc. Their custom formulated products are designed to meet specific performance properties in a number of different industries, including the aerospace, medical, optical, electrical, electronic and other manufacturing industries. Master Bond’s 100% reactive coatings contain no solvents or diluents and aim to minimize the impact on the environment. Ultra low viscosity coatings are also available for use in confined spaces to minimize health risks.
MG Chemicals
Conformal coatings for different applications
MG Chemicals aims to provide acrylic, silicone and urethane based conformal coatings to meet different application requirements. MG Chemicals’ acrylic coatings are fast drying and do not require special equipment to apply. They are particularly useful in manufacturing processes that require quick turnaround times. Silicone and urethane coating products from MG Chemicals are designed to protect PCBs against moisture, corrosion, and thermal shock, and their optically clear conformal coating epoxy is used mainly in corrosive environments to improve reliability, operational range and lengthen the life of electronic and LED parts.
