RISO ComColor® high-speed inkjet printers employ 24 in-line Piezo drop-on-demand print heads. Each of the four colors (cyan, magenta, yellow, and black – and in the case of the ComColor GD Series, the fifth color of gray) has six print heads in a row imaging the page.
Piezo print heads use vibration to create ink droplets. The print heads are stationary and the paper passes underneath them. As the paper moves beneath the print heads the print heads lay down the individual colors that make up the four-color print: cyan, black, magenta, yellow.
The fixed position of the print head makes possible the high printing speeds found in ComColor inkjet printers, and it also results in a longer life span for the equipment.