Optimizing White Ink Printing with Banded Anilox Rolls

Printing with white inks presents unique challenges, particularly in achieving optimal opacity, printability, and efficient drying. A banded anilox roll is a valuable tool that allows printers to test different cell volumes and geometries to enhance print performance. This approach helps optimize ink usage while improving print quality.

Enhancing Opacity for Full Coverage Print

Achieving high opacity when printing full-coverage areas can be difficult due to pin-holing, where spots of the substrate remain uncovered. This results in lower opacity readings than desired. To combat this, a banded anilox roll with varied cell volumes and geometries across the roll face can be used. Testing these engraving variations with modern printing plate technologies can also improve results. For example, using printing plates with “textured” surfaces has proven to enhance opacity by allowing better ink laydown.

Improving Printability Without Over-Impression

A common mistake when printing white ink is increasing print impression to improve opacity. While this might help, it goes against the recommended “kiss” impression method, which ensures optimal print quality. Excessive impression can lead to defects such as:

• Bounce:  Excessive impression forces the anilox roll away from the plate surface when coming in contact with the leading edge of the printing plate.  This “shock wave” shows up as horizontal lines of lighter and darker coverage. 
• Dirty Print: Over-impression leads to a build-up of dried ink along and over the edges of the plate surface, necessitating press stoppages for cleaning.

Using a banded anilox roll can help fine-tune the ideal volume and geometry combination, eliminating the need for excessive pressure adjustments.

Addressing Drying Challenges

In many cases, printers use a “double-bump” technique, using two print decks to apply white ink instead of one.  Instead of using one high volume anilox, two lower volume anilox rolls are used.  This method:

✔ Increases opacity
✔ Improves drying efficiency

However, each method has a downside. Double-bumping requires an additional print deck (if available), while a single-pass method usually reduces press speed to allow proper drying. Either way, the best approach depends on the anilox and plate specifications, which a banded roll trial can help determine.

The Role of Supplier Collaboration

Collaboration with suppliers—including plate and ink manufacturers—is highly recommended to maximize the efficiency of white ink printing. Optimizing your printing setup with the right anilox specifications can yield significant benefits for extended anilox roll and doctor blade life.

Conclusion

Utilizing a banded anilox roll removes the guesswork in white ink printing, helping printers optimize print quality, reduce ink waste, and prevent defects. By systematically testing different cell volumes and geometries, printers can achieve better opacity, improved printability, and efficient drying—ultimately reducing costs and increasing productivity.