An inspection machine checks the print quality. The film is unwound and rewound again.

A plastic film printed in gravure or in flexo printing is controlled on an inspection machine with regard to its print quality. Instead of the inspection machine, however, the printing press can also be followed by a slitter rewinder or a coating machine. In all cases, the plastic film is unwound at the unwinder.

This results in electrostatic charges that are difficult to eliminate.

Depending on how highly the plastic film has been charged by the process in the gravure or in the flexo press, high to extremely high electrostatic charges of well over 100 KV occur during unwinding, with flashes on the plastic reel. The high-energy flashes can injure the operators and dirt or even insects from the environment are attracted to the film. The web speed is approx. 400 m/min.

Our solution

The extremely highly charged plastic film can be discharged by using 2 to 3 discharging bars. Correct positioning and the type of bar used is crucial for success.