APPLICATION OF THE MAGNETRON ACTIVATED DEPOSITION PROCESS (MAD-PROCESS) TO COAT POLYMER-FILMS WITH ALUMINA IN WEB COATERS

There is an increasing interest in thin transparent oxide layers as pe rmeation barriers for packaging applications. Nevertheless, these prod ucts are entering high volume industrial production only slowly. One m ain barrier to the broad introduction of thin oxide layers are the hig h investment costs for a new production plant. A possible way to promo te the commercialization of aluminum oxide layers is to modify already existing roll coaters. This concept leads to three technological task s: (a) reactive evaporation of aluminum from boat evaporators at high deposition rates; (b) process control for quality assurance of alumina coatings; (c) plasma-activated deposition at high deposition rates an d large web width. From this point of view, the plasma activated depos ition process of alumina layers in a conventional roll coater has been studied at high web speeds.