The Kyocera Water Printhead KJ4B‑QL is a high‑precision industrial inkjet printhead engineered for high‑speed printing with aqueous (water‑based) inks. It belongs to Kyocera’s KJ4B family of printheads, which are widely recognized in wide‑format and industrial digital printing applications for their stable jetting performance, consistent droplet control, and reliable durability. 

This printhead is specifically optimized for printing at 600 × 600 dpi resolution, delivering crisp images and smooth gradients at high production speeds. With a maximum drive frequency of up to 30 kHz, it provides excellent throughput suitable for signage, textile, décor, and large‑format graphics printed with water‑based ink formulations.

At the heart of the KJ4B‑QL is its wide nozzle array, consisting of 2,656 total nozzles arranged across a 108.25 mm (approx. 4.26″) print width with a tight 0.042 mm pitch. This configuration enables precise ink deposition across a broad swath, improving printing consistency and print quality.

Key Features

• Designed for high‑speed aqueous ink printing — supports rapid output while maintaining print fidelity

• 600 dpi resolution — ideal for detailed graphics and photographic quality prints.

• Large nozzle count and wide print width — 2,656 nozzles across 108.25 mm for broad coverage and efficient printing.

• Small drop volume options — capable of ejecting droplets in 5 pL, 7 pL, 12 pL, and 18 pL sizes to balance speed and quality.

• Internal filtration system — prevents debris from reaching the nozzle plate, enhancing reliability and reducing clogging risks.

• Built‑in temperature control (internal heater) — helps maintain optimal ink viscosity and consistent jetting behavior during extended runs.

• Robust industrial build quality — designed for demanding production environments where uptime and durability are critical.

Technical Highlights

• Ink Type: Aqueous (water‑based) ink formulations.

• Nozzles: 2,656 jets arranged at 0.042 mm pitch.

• Print Width: ~108.25 mm effective width

• Resolution: 600 × 600 dpi.

• Drive Frequency: Up to 30 kHz.

• Drop Volume: 5 pL, 7 pL, 12 pL, 18 pL options.

• Maximum Linear Speed: ~75 m/min (high throughput).

• Dimensions: Approx. 200 × 25 × 59.3 mm.

• Dry Weight: ~420 g.

• Optimal Ink Viscosity: 5.0–6.0 mPa·s.

• Country of Origin: Japan.

Usage & Compatibility

The KJ4B‑QL model is available in multiple versions, including standard configurations and versions with integrated head cables for specific printer platforms, such as MS printers and EFI Reggiani systems. Care must be taken to choose the correct model, as these are not interchangeable across all machines.

This printhead is compatible with a variety of roll‑fed or flatbed industrial printers that use water‑based ink for high‑resolution production printing, including MS Italy JP6, MCS Eagle, Xerox Rialto 900, and other wide‑format systems