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Consider the following two questions:

1. Is your company a supplier of electronics or PCBs to the automotive industry?
2. Are you or your team responsible for assuring a steady supply of quality products such as conformal coatings and encapsulants? 

If so, we would respectfully ask you to consider adding IATF 16949 certification to your list of requirements for your key suppliers. 

Many coatings suppliers continue to focus on minimizing costs and maximizing profits. As a result, most have not taken the time or expense to get themselves IATF certified. In our conversations with major OEMs, we can assure you that the IATF certification of your suppliers can be of great value and help you sleep better at night.

Related Article: Understanding IPC-CC-830B Qualification Standards 

For decades, Chase Corporation and our Humiseal brand have been the originators and recognized leaders in PCB protection with conformal coatings. Humiseal also provides products and technical support for a complete line of encapsulants. While conformal coatings provide adequate protection in most instances, sometimes you just need a little more coverage! Humiseal encapsulants add a whole new level of protection against extreme temperature and chemical exposure.

So, if you currently use Humiseal conformal coatings, there are certain industry-established methods, both manual and automated, for applying them. This usually involves either spraying them, manually hand brushing conformal coatings, or dipping the entire board. Encapsulants are quite different and the following are some common application methods with pros and cons to help in your decisions.

Conformal coatings offer tremendous protection to printed circuit board assemblies, but this assumes they properly adhere to the PCB. Application errors are all too common, causing delamination and otherwise poor adhesion of the material. So before producing at scale, you should routinely conduct adhesion tests to validate the integrity of your production processes.

This blog post outlines the techniques required for the removal of HumiSeal UV cure conformal coating. The products covered in this article are:

• UV40, UV40-250
• UV50LV
• UV500, UV500LV

HumiSeal® has been manufacturing its products in Pune, India for over eight years.Duringthistime we have significantly invested in our site--including manufacturing equipment, quality test equipment, and staff.   

Our facility is now unmatched in its level of manufacturing equipment, technology, and product quality. Although the factory primarily supports the Indian market, it will also join our other manufacturing sites around the World to deliver manufacturing redundancy to our wider customer base around the globe as and when required. 

Conformal coating is generally the last step in the PCB manufacturing process and the method of protection for all those valuable functional components, but it's not always that simple. Let's look at a fairly common scenario.

Everything was moving along fine through the design and testing process. You have begun production spraying and suddenly there are wisps of translucent webs floating in the air. Your taller components look like a scene from the movie Arachnophobia. This is the oft-dreaded cobwebbing effect; and while it may appear confounding and a little scary, it is often one of the simplest problems to eliminate when conformal coating.

In this brief article, we will discuss the likely causes of this odd situation and provide some simple solutions to get you back to applying your coating in a defect-free manner.   Let's begin by exploring the phenomena in more detail.

If you're familiar with HumiSeal through our blogs, you know we are big fans of conformal coatings. This is for good reason; with advancing conformal coating technology, innovative LED and UV curable coatings offer incredible protection for a large range of applications.

Conformal coatings are just one method of circuit board protection available to engineers. Those involved with PCBs may be familiar with the terms encapsulation. Encapsulation is a tremendously powerful method to secure and protect PCBs by submerging them in a protective material. In many cases, this is more desirable than selectively applying conformal coatings.

Bubbles. They can be a real challenge in any adhesive or coating, but they are particularly undesirable when covering electronics and printed circuit boards (PCBs) with fluid conformal coating material. The technical support engineers at Humiseal have over five decades of experience in support of PCB manufacturers. They report that bubbles within the finished film are the most commonly reported technical issue they receive.

In this brief article, we will discuss many of the causes as well as many potential solutions to the problem of entrapped bubbles.

Toluene and Xylene: solvents that have shown value and utility within the adhesives and coatings industries for decades. However, they often serve as a double-edged sword, offering superior solvent and drying capabilities but accompanied by some negative health and environmental impacts.

Before we look at conformal coating in the 21st Century, it is worth looking at how our industry has changed since the 20th Century and the effect these changes have had on reliability. 

30 years ago, we had:

• Through-hole PCAs with axial components and wide conductor spacing (see fig. 1)
• Round axial components that were easy to conformably coat
• Wide conductor spacing (causing a few problems with dendritic growth)
• Leaded solder
• The widely adopted practice of cleaning before conformal coating

Fig. 1

Now move forward 30 years. In that time, surface mount components have been developed that are predominantly square with sharp edges, conductor spacing has been reduced, and packing densities have increased to levels never dreamt of in the past (see fig. 2).