TRIPLE GUN BUBBLE JET PRINTING
Original Publication Date: 1985-Aug-31
Included in the Prior Art Database: 2004-Apr-04
Xerox Disclosure Journal
In the existing thermal ink jet printers, also referred to as bubble ink jet printers, ink droplets are ejected therefrom on demand by pulse heating small resistors in capillary ink-filled channels. The channels terminate at one end with a nozzle or orifice and the other end connects to an ink supply chamber. Each channel has one individually addressable resistor located near the nozzle. When the resistor is selectively addressed with a current pulse, the ink in contact with the resistor is momentarily vaporized to produce a bubble that causes the ink to bulge from the nozzle. At the start of the bubble collapse, the bulging ink breaks away from the nozzle and is propelled toward a recording medium. This method is quite satisfactory for low density capillary channels, such as 150 per inch, but channel wall thickness necessarily causes a dimensional problem with high densities.