Solve critical BOPP label printing issues like streaking, ink adhesion failure, and color shifts. Optimize your flexo process for high-quality "label printing" with actionable fixes for "BOPP label" challenges.

1. Intermittent Spotting

Issue: Random ink gaps in solid-color areas due to uneven ink transfer.

Causes:

- Mismatched anilox roller (incorrect LPI/ink volume).

- Poor BOPP film flatness or surface irregularities.

Solutions:

- Replace/clean worn anilox rollers; optimize LPI for BOPP film.

- Upgrade to premium-grade BOPP materials; calibrate web tension controls.

2. Dot Gain

Issue: Blurred edges or oversized dots, reducing color accuracy.

Causes:

- Excessive plate cylinder pressure.

- Low ink viscosity or high anilox LPI (e.g., 800+).

Solutions:

- Reduce printing pressure; use high-viscosity inks.

- Lower anilox LPI (e.g., 600→400) to limit ink release.

3. Pinholes

Issue: Tiny voids in solid areas caused by trapped air/static.

Causes:

- Static attracting dust; poor ink wettability on BOPP film.

Solutions:

- Install anti-static bars; use low-surface-tension inks.

- Apply corona treatment to enhance BOPP adhesion.

4. Streaking

Issue: Vertical/horizontal lines from scratched anilox rollers or ink clumps.

Causes:

- Damaged rollers; ink drying too fast.

Solutions:

- Deep-clean anilox rollers regularly.

- Adjust ink solvents/add slow-drying agents.

5. Poor Ink Adhesion & Flaking

Issue: Ink peeling off BOPP labels.

Causes:

- Mismatched ink-film compatibility; incomplete drying.

Solutions:

- Use BOPP-specific inks with primers/additives.

- Optimize UV curing systems; add drying agents.

6. Color Fading/Shifting

Issue: Inconsistent hues across batches.

Causes:

- Plate wear; material surface energy variations.

Solutions:

- Replace aging flexo plates; calibrate printing pressure.

- Test new BOPP batches for surface energy consistency.

7. Wrinkling

Issue: Film creasing causing misregistration.

Causes:

- Incorrect web tension; thermal expansion mismatches.

Solutions:

- Install precision tension controls; monitor humidity/temperature.

- Adjust tension settings for different BOPP widths.

8. Material Property Changes

Issue: Challenges with biodegradable/compostable films.

Causes:

- Variable surface energy affecting ink adhesion.

Solutions:

- Collaborate with suppliers to test ink formulations.

- Modify drying methods (e.g., IR vs. UV) for new films.

Mastering BOPP label printing requires balancing anilox roller specs, ink chemistry, and tension controls. Addressing these 8 flexo defects ensures vibrant, durable labels—critical for dominating competitive markets like "label printing" and "BOPP packaging."

Struggling with BOPP label quality? Talk with us on www.sigapackaging.com for tailored flexo troubleshooting and ink optimization guides!