Static and Inkjet Printing on Bottles

One of the biggest issues in winter, besides being cold, is static.  An outside sales representative was responsible for selling and servicing industrial inkjet printers.  He started to receive more complaints about the quality of the print, especially from customers that used plastic bottles.  This customer was printing a date code on the outside of a soda bottle prior to packaging.  They noticed that the print on the back side was blurry and could be rejected by their distributor.  We discussed how static can cause issues like this with printers.

We had a good discussion about how to solve their problem because EXAIR is the leader in Static Eliminators. The quality of the image is based on the dots per inch, or DPI.  With very fine droplets, static charges can affect the “landing” area of the small droplets.  For the application above, the plastic bottles were generating static charge by bumping and rubbing against each other.  A static voltage is generated in either positive or negative charges.  The stronger the charge, the stronger the force.  To measure the static charges, EXAIR does offer a Static Meter to quantitatively measure the amount of voltage of the static surface. 


With a decrease in the moisture that is present in the air, static charges are able to build easier and to a much higher level.  Material is the other condition for static generation.  The type of non-conductive material will determine how easily it will pass or except electrons.  The soda bottles above are made from polyethylene terephthalate, or PET.  This material has a moderate ability to generate static electricity.  But the charge was enough to affect the print quality. 

Ionizing Bar
Low cost Ionizing Bars eliminate static cling.

                With the nature of static elimination, we want to target the affected area.  In this instance, it was just before the inkjet printer.  I recommended the model 8003 Gen4 Ionization Bar with the model 7960 Gen4 Power Supply.  The EXAIR Static Eliminators are able to produce both positive and negative ions to neutralize any type of static.  They were able to mount the Gen4 Ionizing Bar alongside the bottle near the print area.  After they added the Ionization Bar, the static was removed and the date code printing was clear.  They were so impressed that they contacted the manufacturer of the inkjet printer to have this as an option for similar applications.  Static is a nuisance, and EXAIR has nine different types of Static Eliminators to handle industrial areas as well as labs and clean rooms.  If you are experiencing static issues, you can contact EXAIR and speak to one of the Application Engineers.  We will be happy to help you select the best solution for your static problems.    

John Ball
International Application Engineer
Twitter: @EXAIR_jb