The CF6 printhead (formerly Toshiba's) of RISO TECHNOLOGIES was shown at the 2024 Japan Inkjet Technology Expo, printing 2pt font lowercase letters with an increased gap of 6 mm.
The CF6 printhead that RISO introduced this year is based on the previous CF3 printhead, which is air-cooled and measures 96.7 x 29.3 x 100.7 mm. There is also a CF6R variant that has the same specifications except that it uses water cooling and is slightly thicker at 31.3 mm, with the same width and height. The CF6 and CF6R are 1.5 times faster than their CF3 counterparts. Daijiro Kikuchi, manager of RISO's overseas sales department, said the main differences between the CF3 and CF6 are droplet volume and frequency. The CF6/R produces a native droplet size of 6 pL, but can eject up to three drops, producing droplet volumes of 12 pL and 18 pL at a frequency of 12 kHz.
The new printhead can handle both UV-curable and oil-based inks. Like the CF3 series, the printheads are fully recirculated. With a total of 1,278 nozzles arranged in two rows, the printhead offers a resolution of 600 npi and a single-pass print width of 53.95 mm. However, the printhead can also be configured as a dual-pass with half the number of nozzles and half the resolution and a print width of 53.91 mm.
In addition to this, it is designed as a replacement for the CF3/R, so the dimensions, electronic connections, and plumbing are the same as the older printhead. "This means that if a customer has already developed a printer with CF3, tomorrow the customer can use the CF6 printhead," explains Daijiro Kikuchi.
The printheads are suitable for a range of markets, including the decoration of items such as glass, wood, and plastic, as well as direct forming and PCB production, coding and marking, and label and corrugated printing.
He acknowledged that in Europe, many customers are moving to single-pass corrugated printing with water-based inks, but said that different applications require different qualities of corrugated paper, and some customers will continue to use oil-based inks for corrugated printing, while others will use UV inks. He added, "We believe that this printhead will be suitable for corrugated printing applications using UV-curable inks."
Key Features of the Inkjet Printhead CF6/CF6R
The 600 npi printhead is capable of producing a minimum droplet size of 6pL, which increases productivity by 150% compared to conventional models ("CF3/CF3R").
1. Droplet volume control for each nozzle (fine adjustment)
The ability to control the droplet volume for each nozzle helps to further improve image quality.
2. Full-channel inkjet head ink circulation feature
Nozzle-level ink recirculation, high jetting reliability, and low environmental impact
Stable jetting is possible even with large particles or high-density inks.
| 1 color | 2 colors | |
| Print method | On-demand piezo technology | |
| Ink recirculation structure | Ink recirculation through all channels | |
| Print Width | 53.95 mm | 53.91 mm |
| Number of nozzles | 1,278 | 639 |
| Nozzle resolution | 600 npi | 300 npi |
| Number rows | 2 | |
| Nozzle spacing (row-to-row distance) | 7.94 mm | |
| Greyscale levels | 4 levels/0-3 drops | |
| Drop volume | 18 pl/3 drops | |
| Minimum drop volume | 6 pl | |
| Frequency | 12 kHz/3 drops | |
| Printhead power voltage | +7V~+15V, -7V~-15V | |
| Driver circuit power voltage | 5v, 24v | |
| Ink types | UV-curing & oil-based | |
| Built-in temperature sensor | Included | |
| Head cooling method | CF6: Air-coolingCF6R: Water-cooling (includes water cooling port) | |
| Size, weight | CF6: 96.7mm (W) * 29.3mm (D) * 100.7mm (H), 255gCF6R: 96.7mm (W) * 31.3mm (D) * 100.7mm (H), 285g | |
CF6/CF6R is a native 600 npi printhead with two rows of nozzles that are staggered 1/600 inch laterally. When used with 2 colors, the dot positions are staggered accordingly.
Gradation levels and droplet volumes depend on the type of ink used. Maximum print speed and linear frequency can be increased by reducing the number of drops per dot (dpd).
CF6 and CF6R have the same specifications as CF3 and CF3R except for droplet volume and frequency.
Six power supply units are required to drive the printhead (one unit for +5 V, one unit for +24 V, two units for +7 to +15 V, and two units for -7 to -15 V).
