In contrast to previous effect foil applications, for which a letterpress or flexographic unit is necessary, FoilStar applies the cold foil using two conventional offset printing units. The first unit uses its inking unit and an offset printing plate to apply glue either as a spot application or to the entire sheet.
The second, actual cold foil unit features take-up and take-off units for applying the foil. Along with the sheet, the foil is fed into the nip between the blanket and the impression cylinders and applied by pressure to the parts of the printing stock coated with glue. When the backing is removed, the metal layer remains on the sheet. Subsequent overprinting of the foil enables a great variety of color nuances to be achieved. The flexibility of varying the number (one to six) and width of the foil webs enables foil consumption to be precisely adapted to the current job. Web tension in foil take-up and take-off and the individual reel diameters are automatically recorded by sensors and permanently monitored. A further benefit is that both printing units can be changed over rapidly and are then immediately available for printing.