ELECTRIZATION OF A HIGH-ORIENTED MULTILAYER POLYMER FILM DURING CORONA TREATMENT
Modern technology for printing on polymer films is characterized by high speeds (from 50 to 300 m / min). Since corona treatment is carried out in one of the sections of the printing press at a speed of the main technological process, the exposure time to the polymer film is very short, therefore it is of interest to identify factors that increase the adhesive properties of polymer films. Corona treatment of the film was carried out in a steady-state regime on a laboratory treater KP1-200 at a power of 750 W for 0.5 s. In this work, the distribution of electric charges on the surface of a highly oriented multilayer polymer film that occurs during the short-term corona treatment process using the method of evaporation of fine powders of various nature, is studied. It was established that after the corona treatment of the film, the distribution pattern of the powders used changes, a certain structuring appears, areas with an increased and reduced concentration of powders are formed, and the grammage of fixed powders increases. It was shown that the largest grammage growth on the surface of the treated film is observed when using XEROX PHASER 3116 toner powder (15-fold growth compared to the surface of the untreated film) and PSE-1 polystyrene powder (8-fold growth). It has been established that the main reason for powder fixing is the nature of the powder, namely its dielectric properties. Toner, which is a filled polyester powder, exhibits the greatest ability to be fixed on the charged surface areas of the treated polymer film. It was shown that during the corona treatment of the film for 0.5 s, uncharged electric fields are formed on the surface of the films, which can remain after mechanical removal of the evaporated powder and after exposure to the film surface with a solvent.