Environmental Technologies:Technology Development:Products
–Improvement of Ink Use Efficiency–

Ricoh’s GELJET printer features high-viscosity ink, developed to enable high-speed duplex printing on plain paper with high picture quality to support work at offices. Furthermore, to achieve high-volume continuous output, the print head and ink cartridges are separate from each other. To ensure stable printing performance with this layout and using a viscous ink, a state of negative pressure¹ needs to be maintained inside the print head. Previously, to create a constant negative pressure condition within the print head, the GELJET printer was designed to regularly eject ink, even when the machine was not in a printing operation, resulting in the unnecessary consumption of ink. Seeking solutions to this problem caused by the repeated ink ejection pattern, Ricoh developed a new technology to create a constant negative pressure condition within the print head. The key element is a newly developed pump that can convey ink in two directions between the head and the cartridge, as opposed to the conventional one that allows ink to flow only in one direction, from the cartridge to the head. The new dual-direction pump enables the printer to create and maintain a negative pressure status inside the print head by sucking ink from the head towards the cartridge, thus saving ink by eliminating the need for ejection while the printer is not in operation. The new method is also beneficial as it has remarkably improved ink usage efficiency, because less ink is consumed for printing the same volume. This benefit is particularly notable for low print volume users², for whom the frequency of the motion for creating negative pressure is relatively high in proportion to print volume. After the first mounting of the innovative pump on the IPSiO GX e3300 printer, released in May 2009, it was employed on the IPSiO GX e5500 series, which was launched in February 2010. Following this recent utilization, the new technology will be mounted on newer models rolled out in the years to come.

• 1Refers to a condition of a given area in which gauge pressure is below zero
  (i.e., negative) compared with the ambient air pressure.
• 2Users whose monthly print output ranges approx. from 50 to 100 pages.