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Conformal coatings have a long and storied history with printed circuit boards. A good conformal coating protects PCB components from moisture, corrosion, contaminants, and additional PCB threats like vibration and thermal shock. Coatings are a complicated science, and there isn’t one best coating or application method for every job. These choices are dependent on the design, use case, and assembly of the PCB. For instance, manual brushing PCB coating material is a slow, tedious process; but for small batch applications, it’s quite cost-effective.

Regardless of the chosen method, there are fundamental application errors that can occur, leading to defects forming in the coating which ultimately limit the functional service life of the PCB.

Conformal coating technology is on a continuous path of improvement, and we're excited to say the latest step on that path just happened. UV550 is the most recent innovation from HumiSeal, continuing the trend of industry-defining capabilities in the conformal coating space. This is to be expected from the original inventors of conformal coating material. But what sets UV550 apart from the rest?

Let's discuss how the ever-changing requirements of the automotive and white market space fueled the thresholds this uv-curable material attains, especially with regard to its durability under the most extreme thermal and mechanical cycling conditions.  

HumiSeal development specialists have been designing high-performance, UV-curable conformal coatings for approximately three decades. Compared to legacy solvent-borne and silicone technologies, UV- curable coatings provide some unique properties that can be of great value such as- 

• Nearly instantaneous, consistent curing 
• Superb moisture and environmental protection
• Little or no VOC content

These coatings also lend themselves well to high-speed and high-volume applications due to manufacturing advantages such as- 

• Minimal WIP due to immediate cure capability 
• Low material cost due to 100% solids chemistry
• Smaller manufacturing footprint due to much smaller curing equipment

We at HumiSeal are no strangers to conformal coatings; and if you’re reading our blogs, it’s likely you’re familiar with these coatings as well. The word “conformal” is descriptive of the function of the coatings which are expected to spread and conform evenly across all surfaces that are to be protected. This uniform and even distribution is necessary to protect delicate electronic components from things such as humidity, water, vibrations, and thermal damage (to name a few).

We at HumiSeal would like to dedicate a bit of time and space to one of the most often ignored factors related to successful conformal coating processes: Clean Air.

The transition to LED curable conformal coatings is beginning to build momentum, beginning as a slow evolution and developing into a revolution of sorts. The driving forces behind this include: 

• Improved processing equipment designs and availability 
• Aging or outdated application equipment replacements 
• Increasing range of LED curables commercially available or in development 
• Rising labor, equipment, and energy costs  

If you and your organization are faced with aging equipment and higher costs, there isn't a better time to consider the potential advantages of LED curable conformal coatings! 

Chase Corporation, through our HumiSeal® and Resin Designs divisions, has spent the past decade preparing protection and reliability solutions for complex electronics. Notably, within the emerging EV market, we have identified needs within the assembly of EV motors where superior adhesion and protection are particularly critical.  

Conformal coating with parylene is a very different process compared to coating with traditional solvent-borne or UV curable materials. Parylene coating has some advantages including

• a very thin application profile,
• uniform and complete surface coverage, and
• generally excellent protection and minimal outgassing potential.

On the other hand, parylene coating also presents unique challenges such as

• a significant investment in complex equipment,
• batch processes that limit productivity and increases costs, and
• the user’s inability to selectively control where the coating is applied.

It is this final challenge that we will concern ourselves with within the following discussion.

Most anyone over the age of 30 has probably seen Back to the Future and remembers Marty McFly. One line of Marty’s that inexorably drew him into ill-advised actions was the classic “Nobody calls me yellow.” Nothing good comes from yellow, and this turns out to be just as applicable in LCD screen manufacture as it was in the movie.

You have a lot of options regarding the packaging of your adhesives and coatings. In this blog installment, we will discuss characteristics, advantages, and concerns regarding one of the more unique alternatives: Bladder Bags