Broken Lines or Missing Characters in Inkjet Printing: Causes and Solutions | Cheef Inkjet

Broken Lines or Missing Characters in Inkjet Printing: Causes and Solutions

When an inkjet printer outputs text with incomplete strokes, broken lines, or missing characters, it directly impacts product traceability and compliance. This common issue affects all types of systems—CIJ, TIJ, and DOD—and is typically linked to nozzle obstruction, ink instability, or software malfunctions. Here’s a detailed guide to diagnosing and fixing this printing defect.

Common Symptoms

• ⚠️ Characters with missing dots or partial strokes
• ⚠️ Entire words or numbers occasionally skipped
• ⚠️ Vertical lines or barcodes appear fragmented
• ⚠️ Intermittent defects that vary by speed or product surface

Major Causes and Solutions

1. Clogged or Partially Blocked Nozzles

• Cause: Dried ink or dust particles obstruct droplet ejection
• Fix:
  • Clean nozzle using approved solvent and soft cloth
  • Run multiple auto-clean cycles or backflush (CIJ/DOD)
  • Replace cartridge (TIJ) if cleaning fails

2. Ink Flow Inconsistency

• Cause: Air bubbles, clogged filters, or worn pump cause pressure drops
• Fix:
  • Check for air in tubing, run prime cycle
  • Replace ink and makeup filters regularly
  • Inspect pump pressure and replace if degraded

3. Environmental Factors

• Cause: Humidity, temperature, or static electricity affecting ink jetting
• Fix:
  • Maintain ambient temperature between 18–30°C and RH <60%
  • Use anti-static brushes or grounding strips near the printhead

4. Incorrect Printhead Distance or Angle

• Cause: Printhead too far or not perpendicular to product surface
• Fix:
  • Position head within optimal range (CIJ: 2–6mm; TIJ: 1–2mm)
  • Align head using mounting tools or guides

5. Software/Message Layout Errors

• Cause: Field not properly linked or variable not recognized
• Fix:
  • Check and recreate message layout if needed
  • Verify all dynamic fields are connected and updated properly

Best Practices

• ✅ Conduct nozzle test prints during every shift change
• ✅ Log any printing irregularities to track pattern or frequency
• ✅ Use fresh ink within shelf life and mix properly before use
• ✅ Protect printer from airflow, dust, and rapid temperature shifts

FAQs

• Can I temporarily bypass a missing nozzle? Some DOD printers allow compensation; TIJ requires full cartridge replacement
• Why does it only happen at high speed? High speeds amplify minor flow or timing errors—consider slowing the line for critical products

Conclusion

Broken or missing characters compromise the effectiveness of any coding system. By targeting root causes—from hardware to layout—these defects can be quickly resolved. For diagnostics tools, replacement parts, or remote assistance, contact Cheef Inkjet at sales@cheef.cn.