Issue link: https://iconnect007.uberflip.com/i/1487920
36 DESIGN007 MAGAZINE I DECEMBER 2022 Do you see the future of coatings as "greener," or will there always be a demand for the more traditional solvent-based coatings? Solvent-based conformal coatings are the most used conformal coatings in the electron- ics market, and there are many reasons why: ey are easy to use, cost-effective, and there is a wide selection available. Whilst solvent- based conformal coatings are incredibly popu- lar and will surely stay with us for quite some time, we are currently seeing a shi to a more careful attitude regarding our finite resources and a desire for more environmentally friendly and sustainable conformal coating products. Specifically with younger generations on the electronics consumer side, but also in the work- place with product designers, electronic design engineers, chemical engineers, marketers, and others, there is a growing interest in sustain- ability and environmentally friendly solutions, as well as a willingness to create products that really make a difference. is attitude shi has been filtering through the supply chain, creat- ing pressure to meet this demand for a greener approach to manufacturing and, ultimately, a greener future overall. Alongside this environmentally conscious perspective, a demand for protective mate- rials that will allow electronics to withstand harsher environments has also materialized in the industry. Such requirements are becoming more stringent every day, and the pressure is on manufacturers to meet this evolving need. As it turns out, our research has shown that natural materials—including materials from food waste, for instance—can provide similar or better properties and protection than con- ventional options. With such promising char- acteristics, it seems only logical to dig into these renewables for coating product develop- ment. Nature is providing us with better solu- tions that are as sustainable as they are effi- cient, so there appears to be a definite future for "greener" conformal coatings. What is the benefit of a secondary chemical cure in UV curing conformal coatings? When we look at the traditional UV-cure conformal coatings, we find materials that have a UV primary cure and a secondary mois- ture cure. is means that wherever the cor- rect UV light wavelength reaches the coating, it will cure the material within a matter of sec- onds. However, the issues lie within the areas that are not reached by the UV light. Between high components or under component parts, we still want the conformal coating to cure to ensure even protection. For those areas, we will need the secondary cure. Many common UV-cure coatings use atmo- spheric moisture for their secondary cure, which can release by-products that produce a strong odor. In applications where the PCB is placed in an airtight enclosure, the available moisture can be limited, potentially resulting in an insufficient cure and limited protection of the electronics. erefore, it is important to leave the coated PCB until the secondary cure has fully taken place. Depending on the UV coating, the secondary cure can take days, weeks, and, in some cases, even months. However, with a chemical cure as the second- ary cure, the chemical cure will happen with the conformal coating. is is because, rather than relying on a single component material, this process uses a material that consists of two parts, part "A" and part "B," that will react when mixed to complete the cure. So, aer the UV primary cure has taken place, the material will go into the secondary cure phase without the need for any environmental input. Nature is providing us with better solutions that are as sustainable as they are efficient...