Mechanical Print Damage
Printing Flaws

[Flexo Flaw Fixing] Mechanical Print Damage

This article is part of the FLEXO FLAW FIXING series

In the dynamic world of flexo printing, the quality of the printed result is paramount. However, a common problem in flexo printing that often undermines this quality is mechanical print damage. This phenomenon, featuring an easy scraping or peeling of printed images on the print production line, is a significant challenge. Addressing it requires a thorough understanding of its causes, as well as effective remedies and prevention strategies.

Causes and Remedies of Mechanical Print Damage

Improper ink formulation or damaged ink
  • Cause: The foundation of a durable print is the ink you use. An inappropriate ink formulation or degraded ink quality can drastically reduce print durability.
  • Remedy: The remedy is twofold: first, the ink system must be thoroughly clean by the removal of any residues or contaminants. This is followed by replacing the old ink with a new batch, correctly formulated for the application, to ensure a robust foundation for printing.
Insufficient Anilox Roller Volume
  • Cause: A critical component in the transfer of ink, the anilox roller volume, if inadequate, will result in an inadequate layer of ink on the substrate. This thin layer is more susceptible to damage.
  • Remedy: The remedy is simple – replacing the current anilox roller with one that has the appropriate volume capacity is essential to ensure a sufficient ink layer and therefore print durability.
Inappropriate Solvent Use
  • Cause: The role of the solvent in the ink formulation cannot be overemphasised, as its improper selection can affect the adhesion of the ink to the substrate.
  • Remedy: The use of a properly mixed solvent, preferably fresh, is critical. This will ensure that ink adhesion is optimised, reducing the likelihood of mechanical damage to the print.
Insufficient Corona Pre-treatment
  • Cause: Corona pre-treatment is necessary for the ink to adhere effectively to the substrate, especially in the case of films. Inadequate treatment results in poor ink adhesion, which increases the susceptibility of the print to mechanical damage.
  • Remedy: The implementation of an inline corona pre-treatment process can significantly improve the ink adhesion properties and strengthen the print against damage.
Low Abrasion Resistance
  • Cause: The ability of an ink to withstand physical contact without wearing away is critical. Low abrasion resistance is a direct route to mechanical damage to the print.
  • Remedy: Incorporating a wax additive into the ink formulation can significantly improve the abrasion resistance of the ink, thereby increasing the durability of the print.

Conclusion

Addressing mechanical print damage in flexo printing is not just about fixing a defect. It’s about ensuring the integrity and longevity of the printed material. Through careful consideration and application of the remedies outlined, practitioners can significantly reduce the incidence of such damage.

Adopting these preventive strategies represents a commitment. It improves the quality and durability of printed output that are hallmarks of excellence in flexo printing. The industry can continue to thrive in this way. Also, it ensures the delivery of products that meet and exceed the demands of an ever-evolving marketplace.