Triboelectric effect is simply a large word that means when two materials of a certain nature come into direct contact with one another, they will become electrically charged. The “certain nature” that I mentioned above usually means materials that are electrically non-conductive. Wool, glass and PVC plastic would be three very good examples.

This is where things begin to not make much sense. Think about it, materials that are electrically non-conductive generate an electric charge when they are brought into close contact with one another. Notice I didn’t say anything about friction or rubbing action to cause the electric charge generation. The materials simply have to come together for this to happen. Friction or rubbing can be a component, but is not necessary.

It isn’t until you go to separate these materials in an application where you really begin to see the problem. This was the case for a customer who printed onto PVC boards. The board faces were covered with a protective film to protect against damage. Everything was going OK in the application until the film was peeled off the PVC board. The simple action of peeling off that protective film generated huge static charges due to the imbalance of positive and negative charges on each material surface. Again, note that there was no vibration, rubbing or friction of any kind.

Another good example of this kind of effect is when a material such as mylar is fed into a machine from a master roll. The action of the top layer of mylar separating from the roll will, again, produce a rather large static electricity imbalance.

EXAIR makes static eliminators and we can certainly help you with these static issues. I wanted to write an article to help people where to look within their application and why they would want to look in such places as it may not always be obvious what exactly is causing the static electricity to generate. If you know where the problem resides, you can then apply our static eliminating solutions more effectively.

Neal Raker
Application Engineer
nealraker@exair.com