Why use a conformal coating to protect a circuit board?

A fundamental question asked quite often is why do I need to coat?

After all, it costs money and it can be difficult to process. Not very attractive to use it!

However, there are several reasons why a traditional liquid conformal coating or Parylene could be used to protect a printed circuit board (PCB).

These reasons include:

  • Improving the insulation protection of the circuit
  • Increasing the protection of the circuit from attack from high moisture and humidity
  • Increasing the circuits chemical and temperature resistance
  • Making the circuit board more resilient through ruggedisation
  • Improving the dielectric properties of the printed circuit board
  • Creating barrier protection from liquids such as water, blood etc
  • Stopping the board surface getting dirty from contamination that can lead to corrosion long term

To find out more about these reasons read our section why use a conformal coating?

How can we improve Nexus?

Let me know your thoughts on the content and how we can improve our services ?

Contact me directly by email lhitchens@nexus3c.com now.

Dr Lee Hitchens, Author of Nexus website and ebook
Dr Lee Hitchens, Author of Nexus

How do I select a conformal coating?

Dr Lee Hitchens, Author of Nexus website and ebook
Dr Lee Hitchens, Author of Nexus

I am regularly asked how I would go about choosing a conformal coating?

I normally respond to the person involved by asking an awful lot of questions and they wonder what they got themselves in to!

Why do I have to ask a lot of questions?

The questions are there because choosing a conformal coating process is a complicated process usually balancing a lot of important trade-offs and compromises.

When I consider the question I actually see three major parts of the complete process.

These parts are:

  1. The conformal coating material
  2. The application method
  3. The circuit board design

When you consider these three points you have to balance them to create the best compromise process solution that suits your requirements.

This is what I call the Holistic Approach to conformal coating.

So, what should you do next?

It is tempting to consider one of these parts in isolation.

However, this could be a mistake.

After all, the wrong choice can be devastating to the conformal coating production process as a whole and even worse, the reliability of your product.


I feel that to identify the best conformal coating material and application process there are several key factors that you need to consider that, if you are lucky, will add up to at least one sensible process choice.

Factors to be considered include:

  • Temperature operating range
  • International, customer or National Standards
  • Environmental considerations of the circuit board
  • Requirement to rework the conformal coating
  • Conformal coating material type
  • Application process considerations
  • Curing the conformal coating
  • National, State, Regional Legislation and Insurance
  • Supplier performance and availability
  • Price

To find out more about these factors visit Nexus and see how we recommend you select a conformal coating through the holistic approach.


Where to start in Nexus?

Dr Lee Hitchens, Author of Nexus website and ebook
Dr Lee Hitchens, Author of Nexus

My name is Dr Lee Hitchens and I am the author of the Nexus conformal coating website and eBook.

If you’re reading this blog then the chances are you are looking for a piece of information on some area of conformal coating and this is exactly what Nexus was written for.

To start with I thought I would try and answer a few of the basic questions you may have so you can understand what Nexus and I stand for?

What is Nexus?

Nexus is an independent website and eBook dedicated to providing information on all areas of conformal coating and the related topics connected to the process.

This includes Parylene and other deposition processes, fluoropolymer technologies plus the traditional conformal coating materials.

It is made up of a lot of knowledge from many different people from the world of conformal coating that you should find useful.

Why create Nexus?

I have been working in the area of conformal coatings and electronics high reliability for over 25 years in various areas including sales and technical support.

I have also been training people in all areas of conformal coating for almost the same amount of time.

A few years ago I decided that people needed a specific place where they could find all of the useful knowledge on conformal coatings and use in their own production process.

So, Nexus was created and I began writing the website.

I explain a little more here on why I wrote Nexus?

Nexus is Peer Reviewed

This year I decided to re-launch Nexus and create an online eBook.

The major difference with the new site was that the information added was all peer reviewed.

That is people from all over the industry are helping with the quality of the content and helping peer review the information.

This is so the conformal coating knowledge you have from Nexus is as independent as it can ever be and should be able to guide you through most issues without risk of commercial bias.

I hope that you find it the case and the information you find is useful.

So where to start with Nexus?

If you are new to Nexus then a good place to go is our Start Here page.

When people visit our site they go to certain areas. I have tried to indicate these pages directly and help you save some time.

I hope that it works for you.

Finally, this is a continuous project and I am always looking to improve the content. If you need anything specific then let me know and I will be more than happy to help out.

I hope that you find this the case and that you will find all the knowledge you need on understanding conformal coatings and being successful in their application.

Let me know what you think?