My colleagues Alistair Little and Jade Bridges have been sharing their invaluable insights into encapsulation resins and thermal management products for the last few months. But this month I’m back on columnist duty. This is my first of many columns for 2018, and I have decided to share some top trending queries that concern many different applications and areas. LEDs are always a hot topic, as are volatile organic compounds (VOCs) and harsh environment concerns.
I have quite a few years of experience and knowledge of the coatings business, but of course, I’m still learning. Some queries tend to crop up more frequently than others, and I’m happy to provide some insight into these. Without further ado, here are my top queries.
Q. So, I understand that historically the most widely used coatings are solvent-based. Can you explain the main benefits of solvent-free conformal coatings?
A. These are very easy to summarise. Generally, solvent-free coatings tend to use less hazardous raw materials, have lower odour levels, and can be safer for the operator. Additionally, many solvent-free coatings are non-flammable, having a positive impact upon business insurance premiums. Environmental compliance is a growing trend and solvent-free alternatives certainly help to minimise the emissions of VOCs.
Q. How has the trend of miniaturisation affected the development of coatings?
A. The trend towards miniaturisation is most evident within consumer electronics, and has led to the development of ultra-thin coating materials (with thicknesses of less than 12 microns). In the case of mobile phones, for example, the reduced coating thickness in combination with internal gasketing and better case design has enabled the production of increasingly more water-resistant mobile devices.
Considering more traditional applications, such as aerospace and automotive, there is a double whammy effect of finer-pitch components (i.e., reduced space between the conductors) and a requirement to reduce weight, resulting in less protection being afforded by the board housing. Ultimately, the impact of this criteria means that coatings need to function more as a primary mitigation strategy against the environment, and the performance requirements of the materials are increasing dramatically. This is particularly evident in the case of condensation resistance.
To read this entire column, which appeared in the February 2018 issue of Design007 Magazine, click here.
Visit I-007eBooks to download your copy of Electrolube's micro eBook today: The Printed Circuit Assembler's Guide to Conformal Coatings for Harsh Environments.