Ricoh has announced a new thin film piezo-electric printhead, the TH6310F, which is described in the press release as “the flagship model amongst Ricoh’s family of industrial inkjet printheads.” It’s mainly designed for use in single pass packaging and textile printers, as well as high end scanning printers that use a large number of heads. Ricoh has adopted a Z-shape for this head, which should make it easier to slot the heads together to complete a print bar. It’s 104.6mm wide, with a 44.9mm depth and 104mm high. It can produce a print width of 66.7mm.
The head has 1600 nozzles in total, split across two modules in a staggered configuration. Each module has eight rows of nozzles, with 100 nozzles per row, giving a resolution of 75npi each or 600npi run total. Ricoh says that the nozzles have been arranged to minimize the level of turbulence in the air that’s normally created by the rapid ejection of ink, so that the ink drops can fall in a more predictable manner to the substrate surface. This in turn allows for a reasonably wide throw distance of 4mm and should prevent the dreaded woodgrain effect, where the drops fall according to the pattern of the air flow around the nozzle plate.
It has a firing frequency of 80kHz in binary mode with a 5pl drop size, or 40kHz in greyscale, with four multi-drop levels for 0, 5, 10 and 18pl, though Ricoh cautions that the drop sizes do depend on the type of ink used. There’s also an intermediate option of 60kHz for three levels. As such, this head should be capable of producing 600dpi at a speed of 100mpm.
According to the press release, it’s suitable for use with UV, solvent and aqueous but I understand that it will also work with oil-based inks. It has a built-in heater unit but can only cope with a relatively low 5.5 mPa•s viscosity, which is less than Ricoh’s bulk piezo printheads can handle.
The head has a single channel but is designed for full recirculation right past the back of the nozzle plate. This is essential for reliable high speed single pass printers, particularly in the textile market, in order to prevent the risk of nozzles being blocked.
I think it’s worth noting that this printhead has been a long time coming with Ricoh having shown a Z-shaped printhead for single pass use as a concept back at Fespa 2018. Graham Kennedy, head of Ricoh Europe’s commercial inkjet business, told me, “It’s been through a lot of iterations to make sure that it meets the demand in the market.” He added, “We are confident that this will be the fastest, most reliable printhead in the market.”
The new TH6310F is Ricoh’s second head with a MEMs actuator, following the TH5241 head that was announced last year. But where the existing model built on the Xaar 1201 head, Ricoh assures me that this new printhead is not related to Xaar’s 5601 despite the similar Z-shape and Ricoh’s previous collaboration with Xaar. Clearly, given the level of investment required to develop MEMs actuators, we will see more thin film heads from Ricoh.
Several OEMs have been evaluating this printhead and it should be generally available worldwide later this month. In the meantime, you can find further details on the TH6310F printhead from industry.ricoh.com.