Beidseitige Innen‐ und Außenbeschichtung von PET‐Getränkeflaschen

Double‐sided interior and exterior coating of PET beverage bottles Plasma‐enhanced methods for the interior coating of PET beverage bottles have already been put into practice in the industry. Thereby the achieved barrier properties are limited due to defects in the coating, which emerge during the layer growth and allow a higher permeability. One possible way to improve barrier properties is the double‐sided coating. The implementation of the concept in form of a demonstrator plant is presented. By means of optical emission spectroscopy (OES) as a very versatile and easy to use method for the surveillance of industrial plasma processes, the influence of the gas composition on the plasma homogeneity and barrier properties of the coating is demonstrated. Permeation measurements are carried out, showing the potential of the combined coating process for the deposition of effective coatings.