Ricoh G6 Printhead Overview
Ricoh announced the launch of its GEN 6 printhead (Ricoh G6 printhead) on February 28, 2019. There are three types of Ricoh G6 printheads launched this time. The printhead models are RICOH MH5320, RICOH MH5340, and RICOH MH5320 A type.
The new printheads will be launched as higher-spec models of the RICOH MH5420/5440 and RICOH MH5421/5441. Minimized 5-pl droplet size and improved jetting accuracy produce excellent print quality without graininess. In addition, the maximum frequency of grayscale is 50 kHz, which improves productivity.
Each printhead features enhanced bonding technology for improved durability. With these new features, the RICOH MH5320/5340/5320 Type A further enhances its compatibility with UV, solvent, and water-based inks. Specifically, the MH5320’s water-based ink compatibility and service life are more than twice those of the previous MH5421.
In the industrial printing market for sign graphics and textiles, there is an increasing need to meet various customer demands, such as smaller batch sizes and shorter lead times. This has led to the rapid digitization of industrial printing to provide greater flexibility and productivity and increased demand for inkjet printheads to enable high-resolution printing and higher productivity.
By launching this new printhead, Ricoh will meet these market needs. Ricoh will support customers' printer development and jointly create new value in digital printing.
In February 2018, Ricoh announced its growth strategy, "RICOH Ignite," which aims to strengthen its customer base by expanding its printing technology portfolio. Ricoh has been developing inkjet technology for more than 40 years, and today it is used not only for office printing but also for commercial and industrial printing applications in a variety of different sectors, including lifestyle. In addition, it has been enhancing its "display printing" functionality for paper as well as "applied printing," which combines processes and materials to create new customer value.
Ricoh G6 Printhead Specifications
| MH5320 | MH5340 | MH5320 Type A | |
| Method | Piston pusher with metallic diaphragm plate | ||
| Print Width | 54.1 mm (2.1') | ||
| Number of nozzles | 1,280 (4×320 channels), staggered | ||
| Nozzle spacing (4 color printing) | 1/150" (0.1693 mm) | ||
| Nozzle spacing (row-to-row distance) | A: 1.101 mm B: 11.811 mm | ||
| Compatible ink | UV, solvent, aqueous, others | ||
| Total printhead dimensions | 89(W)×66.3(D)×24.51(H) mm (3.5"×2.6"×1.0") | ||
| Weight | 228 g (including 45C cable) | ||
| Max. number of color inks | 2 colors | 4 colors | 4 colors |
| Operating temperature range | 60℃ | ||
| temperature control | Integrated heater and thermistor | ||
| Jetting frequency | 50 kHz (3 levels); 40 kHz (4 levels) | ||
| Grey-scale | 4 levels | ||
| Drop volume | Binary mode: 5 pl/ Gray-scale mode: 5-15 pl | ||
| Viscosity range | 10~12 mPa/s | ||
| Surface tension | 28~35 mN/m | ||
| Ink port | Yes | Yes | No |
| Separately sold parts | MH5320/MH5340/MH5320 Type A dedicated cable | ||
Ricoh G6 Characteristics
High Definition and High Productivity
MH5320 (1 head, 2 colors) MH5340 (1 head, 4 colors)
MH5320 20C (Length: 195 mm) MH5320 45C (Length: 453 mm)
When using 1 color: 150 dpi×4 rows/color → 600 dpi
When using 2 colors: 150 dpi × 2 rows/color → 300 dpi
When using 4 colors: 150 dpi × 1 row/color → 150 dpi
Ricoh MH5320/5340 print head product positioning
jet flow = number of nozzles × number of nozzle holes × ignition frequency, Gen6-MH5320/5340 print head is mainly for the field of industrial high-speed UV printing.
Three Features of Ricoh MH5320/5340 Print Head:
(1) High Productivity
Ignition frequency increased → Ink volume/unit time increased
MH5420 21pl, 20 kHz-512 µl/s
MH5320 15pl, 50 kHz-960 ul/s
MH5420 Binary mode: 30 kHz; gray-scale mode: 20 kHz
MH5320 Grey-scale mode: 50 kHz
MH5320 saves 1/2 of printing time vs. MH53420 under the same DPI.
Example: 600x1200 dpi stable drawing scheme
| car scanning speed | Ignition frequency | Pass number | |
| MH5320 scheme | 1.5 m/s | 35.4 kHz | 4 (x1; y4) |
| MH5420 scheme | 1.4 m/s | 17 kHz | 8 (x2; y4) |
Increase the ignition frequency and reduce the number of passes to achieve the same output image quality. Reduce the requirements for the speed increase of the trolley and reduce the difficulty of the trolley control design.
(2) High Definition
It supports multi-level grayscale printing and provides an optimized visual experience for different application scenarios. Small drops for ultra-close viewing; large drops for long-distance viewing; grayscale for close viewing; smooth tones; and fine type
MH5320 enables smooth and excellent print quality without gaininess. Compared with MH5320, MH5420 has been improved by 50% in ink droplet flight velocity deviation and has been improved by 37% in nozzle position accuracy deviation. The minimum ink drop of MH5320 is 5 pl, and the minimum ink drop of MH5420 is 7 pl.
(3) More Ink Tolerance
MH5420/5440 UV/solvent ink
MH5421/5441 water-based ink
MH5320/5340 UV/solvent/water-based ink. It is able to reduce inventory and extend life. Specifically, the aqueous ink compatibility and service life of the MH5320/5340 is enhanced.
MH5xxx Series Parameter Comparison
| General Properties | MH5320/MH5340 | MH5420/5440 MH5421/5441 |
| Print Width | 54.1 mm | 54.1 mm |
| # of Nozzles | 1,280 (4×320 channels) | 1,280 (4×320 channels) |
| DPI | 600 | 600 |
| Compatible Ink | UV, Solvent, Aqueous
(more ink tolerance) | MH5420/5440: UV, Solvent,
MH5421/5441: Aqueous |
| Max # of colors | 4 | 4 |
| Max Jetting Frequency | 50 kHz (high productivity) | 30 kHz |
| Drop Volume | 5-15 pl (high definition) | 7-21 pl |
| Viscosity Range | 10-12 mPa/s | 10-12 mPa/s |
| Cable Type | Detachable cable (flexible design) | Integrated cable |
