# State of the art of waterproofing

There is a new electronics waterproofing material / technique branded as Liquipel. Not much info is available, but supposedly it is a hydrophobic compound that is applied to the target electronic device by using vapor deposition in a vacuum while ionizing the target device so that the Liquipel particles are attracted to coat every nook and cranny of the device on the microscale.

Unfortunately, no one has chemically tried to identify the composition of Liquipel yet -- for all I know, it could be the same as Rain-X or something equally cheap. And it is not possible to buy Liquipel canisters; the company only applies this coating as a service.

Given that electrostatically-targeted, vapor-deposited, microscale hydrophobic coating seems to be the best way to waterproof arbitrary electronic devices, what is the state of the art in non-proprietary versions of this technique or a similar technique? Does anyone know a chemical that would work in this way? Any instructions for DIY vapor deposition? Or is there any simpler approach, like dipping the whole circuit board in some hydrophobic yet sticky liquid?

• I don't see how this is even remotely related to electrical engineering, or electrical anything in any way. It's maybe suited for physics or chemistry.stackexchange. The only thing related to electronics in the question is a few of the tools. – Connor Wolf May 7 '13 at 2:44
• It seems to me that if someone posts a good answer, it will be a fundamental and valuable technique to most of the electronics engineers here on this forum – AlcubierreDrive May 7 '13 at 3:04
• Yes, but that's true of basically every field that deals with the weather or moisture in any way. By that logic, it would be equally valid on bicycling.stackexchange.com, or howtotakecareofyourfishtank.stackexchange.com. EE.se seeks to address electrical engineering specific issues. – Connor Wolf May 7 '13 at 3:10
• @ConnorWolf I don't agree, because there might bee some EE-specific techniques for water-proofing circuit boards, and the information can be useful to other designers with the same issue. – clabacchio May 7 '13 at 6:52

The best existing solution is something that is called parylene, if you can put a film of this down without pin holes then you can have a water barrier and dielectric barrier. Often used in space and extreme environments. I've seen a 20KV voltage source that looked like a bare board that you can hold in your hand.

Parylene is relatively expensive, partly because of raw material cost, partly because of application technique. It is applied as an evaporative coating, which can be very wasteful as it coats the inside of the chamber so only a small percentage ends up on the board.

Whether of not this Liquipel can be used in electronics will have to be tested. What is important is that you form a physical barrier that bonds to the surface. The material that I saw demonstations of in the past (80% that it is this Liquipel) used a nano-layer to entrain/entrap air as a buffering layer. This material will wear off eventually and counts on a rough surface (nanoscopically) to entrap air which then form the "barrier". So it is using van der waals forces and not covalent bonds. These bonds could be saturated with other materials after mechanical abrasion/contact. Also at corners, say the edges of leads on a IC package I could see that this would be a place where this material might fail as a nanoscale structure might not conform around a corner fully.

But these are areas to look at, not necessarily a reason to reject it until proven not to work.

Paralyne coatings are not similar to the coating that is mentioned by Liquipel. One is a pinhole free thick (micrometer) coating. The other is a thin (nanometer) CF chain coating that covalently bonded to the surface of the material assuming it is not a surface like steel that it won't bond to. This process is used by liquipel and other companies to help protect an electrical device from accidental water damage. Motorola Razr has this on its phones, but it is provided by another company as Liquipel is only user end applications. One thing I can see wrong with using LP is that it will void the warranty since it ruins the LDLs inside the device. Where purchasing a precoated phone from the Manufacture ensures the device is protected against accidents and safe for warranty. The nanometer coating is cheaper to apply to a device as it doesn't require masking since it won't interrupt electrical connections. Its surface morphology increase the available surface area of the device and thus increases it's water repellency. It works in a similar fashion that the tiny hairs on a lilly pad work. Neat stuff it really is. And assuming it is bonded well to the surface of a device it won't just rub off. An at home solution isn't really available unless you have a plasma generator and a high vacuum chamber and the chemical to add. There are after market solutions but you are spray painting the device.

Your description makes it sound very like Parylene which rawbrawb mentioned.

BUT other mentions on web make it sound less so.

So that I am actually answering at least part of your question :-).

Does anyone know a chemical that would work in this way?

Answer: Apparently not, and include Liquipel amongst them.
There are a number of reports of it not working with valuable equipment under well-enough-controlled circumstances.

For the very large amount of money paid (I've seen $60 and$100 mentioned) it seems a very poor deal.

Failure examples:

(1) Here is an online fails in front of your eyes You Tube video

Full immersion at of an iPhone about 29:30 - about 7 seconds immersed. Video start slightly before then.

and end result about 1 hour later here. Reportedly, they had ruder things to say post-show. &

Treatment

• To try out the process we had Liquipel applied to an iPhone 3GS and an iPad 2, lodged via separate retail outlets on different days.

"Test"

• So, we did our own full-immersion experiment in the CHOICE labs, dunking both our devices in a tub of water to see if they would be immune.

Result

• Unfortunately, they weren't. Both devices malfunctioned almost immediately. And, despite being thoroughly drained and dried over several days, neither device recovered.**

• UPDATE: After several weeks of drying out and periodic re-checking, the iPhone has not recovered any useability at all. The iPad, however, has regained some functionality.

• The water markings on the inside of the display screen faded noticeably after about three weeks and the iPad appears to be mostly usable but the hardware Power/Sleep button at the top edge is still NOT working at all, so it can't be used to put the device to sleep, wake it up or shut it down completely.

• The workaround for the sleep/wake function is to use an Apple magnetic SmartCover or to enable the Assistive Touch software options under the Accessibility menu. This presents a software option onscreen that can be used to put the iPad to sleep. However, you can't use this to turn it off. So, for example, it couldn't be taken on a plane because electronic devices must be turned off completely for takeoff and landing.

They added: Liquipel is obviously confident in its claims, providing samples of Liquipel-treated paper tissue with each device returned from treatment. We also subjected them to water to see how they held up. Initial results showed that the process appears to provide a certain amount of water repellency, but from the results we obtained with our electronic devices, obviously we can’t recommend this treatment.

• read my post more carefully, I never said it looked like parylene. I use parylene as a gold standard/reference to an ideal coating. – placeholder May 7 '13 at 17:33
• @rawbrawb - Your answer was fine. I read it carefully and I was not commenting on it per se. Read my post more carefully :-). What I intended to convey (and onviously failed to manage :-) ) was that when I saw HIS question the application description made it sound like Parylene. viz " ... by using vapor deposition in a vacuum while ionizing the target device ...". THEN I saw your answer. Then I looked Liquipel up. – Russell McMahon May 7 '13 at 22:02

Parylene provides a thin conformal barrier layer onto electronics and other devices. The thickness is usually in the 3-15 micron range. The parylene deposition process turns the raw material, which is a powder, into gas in a vacuum chamber. The gas then deposits as a solid all over the parts to provide a thin high-performance polymer layer on top of any circuits or electronics. It is also implantable so electronics can be implanted into the body if they are parylene coated.

Parylene has been used for decades and is the ultimate way to protect electronics. Parylene is a vacuum deposition process and it is typically put onto parts by service providers. It might be more expensive than some coatings, but it is definitely the highest performing conformal coat.

Liquipel only modifies the surface energy to repel water. This works for a while in "splash" conditions but it won't hold up in water submersion over time.