Introduction
In Continuous Inkjet (CIJ) printing, pigment-based inks are essential for high-contrast marking — especially on dark or low-energy surfaces like black cable, rubber, or plastic. However, pigment inks present unique challenges due to the presence of solid particles in the formula.
This article explains what pigment dispersion stability is, why it matters, and how to maintain stable printing performance by preventing settling and clogging.
1. What Are Pigment Inks?
Pigment inks contain finely ground solid colorants (e.g., titanium dioxide for white, diarylide for yellow) suspended in a solvent like MEK. Unlike dye inks, pigments do not dissolve — they require proper dispersion and agitation to stay suspended.
Common Pigment Ink Applications:
- White/yellow print on black cable, tubing, or plastic
- Contrast marking on automotive parts
- Permanent codes on non-porous materials
2. The Problem: Pigment Settling
Over time, pigment particles can begin to settle at the bottom of the ink reservoir or cartridge. If not properly re-dispersed, this can cause:
- Nozzle clogging or blockage
- Inconsistent color density
- Irregular droplet formation
- Filter fouling and pressure drop
3. Why Pigment Stability Matters
Stable dispersion ensures that pigment particles remain evenly distributed throughout the ink. This leads to:
- Reliable color density and contrast
- Consistent jetting and drop shape
- Longer printhead and filter life
- Lower cleaning and maintenance frequency
4. Key Factors Affecting Pigment Stability
| Factor | Effect |
|---|---|
| Particle size | Finer particles are more stable, but harder to jet |
| Ink viscosity | Too low: fast settling; too high: clogging risk |
| Printer agitation | Recirculation or shaking keeps pigment suspended |
| Storage time and temperature | Settling is faster in heat or long idle periods |
5. Cheef Ink Technology for Pigment Stability
At ChinaCIJInk.com, our pigment inks use:
- Advanced dispersants to prevent flocculation
- Micro-milled particles for high fluidity and color strength
- Anti-settling agents that reduce particle sedimentation
- Formulas optimized for popular printers like Videojet, Domino, Linx
Popular Cheef Pigment Inks:
| Ink Code | Color | Application |
|---|---|---|
| C-W485WHITE | White | Black cable, auto parts |
| C-Y490YELLOW | Yellow | Tube marking, rubber hoses |
| C-SL502SILVER | Silver | Decorative, branding marks |
6. How to Prevent Pigment Ink Issues in CIJ Printers
✔ Agitate Before Use
- Shake ink bottles thoroughly before filling tanks
- Use ultrasonic or mechanical stirrers for large reservoirs
✔ Use Circulating Ink Systems
- CIJ printers with circulation (like Domino A-series+) prevent settling
- Avoid long idle times without circulation
✔ Maintain Regular Cleaning
- Flush nozzles and filters weekly
- Use compatible solvent (e.g., Cheef C-V901 cleaner) to dissolve binder buildup
7. Storage and Handling Best Practices
- Store ink between 10–30°C in original packaging
- Avoid exposure to direct sunlight or vibration
- Do not mix different pigment ink batches unless approved
Conclusion
Pigment inks offer powerful advantages in visibility and permanence, but only when properly stabilized and maintained. By understanding dispersion behavior and using professional-grade inks like those from ChinaCIJInk.com, you can ensure consistent print performance, reduce maintenance, and extend the life of your equipment — even in the most demanding industrial environments.
