Missing or Broken Characters in Inkjet Printing: Causes and Fixes

When characters in your inkjet-printed code appear incomplete, distorted, or partially missing, it not only affects readability but also risks traceability failures. This issue can stem from multiple sources—from fluid flow to mechanical misalignment. In this article, we break down the most common causes and offer practical solutions for CIJ, TIJ, and DOD inkjet systems.

Symptoms of the Problem

• ⚠️ Horizontal or vertical strokes in characters are missing
• ⚠️ Letters appear partially formed or faded
• ⚠️ Dots in 2D codes or barcodes are incomplete
• ⚠️ The issue occurs intermittently or only in specific positions

Main Causes and Solutions

1. Nozzle Clogging or Partial Blockage

• Cause: Ink dried at the nozzle tip or internal clogging from contaminants
• Fix:
  • Use a cleaning cycle or flush nozzle with recommended solvent
  • Manually wipe nozzle using lint-free swab and alcohol
  • In persistent cases, replace the nozzle or cartridge

2. Ink Pressure Instability (CIJ/DOD)

• Cause: Ink pump failing to deliver consistent pressure or flow
• Fix:
  • Check pump RPM and pressure gauge values
  • Clean or replace ink filters
  • Inspect ink lines for air bubbles or leaks

3. Cartridge Defect or Low Fill Level (TIJ)

• Cause: Low ink or failed chip on thermal inkjet cartridge
• Fix:
  • Replace cartridge and ensure proper installation
  • Verify cartridge chip is recognized by the printer

4. Incorrect Font or Layout File

• Cause: Corrupted character design or incompatible layout
• Fix:
  • Recreate the layout file or select a different font
  • Run a test print with default system font

5. Electrostatic or Environmental Interference

• Cause: Excess humidity, static electricity, or strong air currents affect droplet path
• Fix:
  • Use anti-static devices or shields around the printhead
  • Control humidity between 40–60%
  • Eliminate fan airflow across printhead area

Prevention Tips

• ✅ Clean nozzles daily or before each shift
• ✅ Replace ink filters on schedule (every 3–6 months)
• ✅ Avoid using expired ink or third-party cartridges not certified
• ✅ Run test patterns weekly to detect early issues

FAQs

• Can this issue affect barcode scannability? Absolutely—missing dots or lines in 2D or linear barcodes can render them unreadable by scanners
• Is character breakage a printhead failure? Not always—it could be a flow or firmware issue; rule those out before replacing hardware

Conclusion

Missing or broken characters in inkjet printing can arise from nozzle issues, ink instability, or digital layout faults. Regular maintenance and prompt troubleshooting are essential to keeping print quality intact. For spare parts, certified ink, or expert repair assistance, contact Cheef Inkjet at sales@cheef.cn.