Common Troubleshooting Solutions in UV Ink Curing
UV ink curing involves polymerizing monomers in the ink binder into polymers using LED UV light of different wavelengths and energies. However, several common problems may arise during the curing process, along with their corresponding solutions:
Poor Drying and Sticky Surface:

Main Reasons:

  • Insufficient UV light intensity
  • Aging or weakened UV lamp
  • Prolonged storage of UV varnish
  • Excessive addition of non-reactive diluent
  • High machine speed


  • Ensure UV lamp energy intensity meets requirements. (Check with your UV ink supplier for requirements, and check with the UV curing lamp.)
  • Regularly update UV lamps and use UV energy tester for monitoring.
  • Opt for LED UV curing lamps with right UV wavelength.
  • Consider adding UV varnish curing accelerator if necessary.
  • Contact IUV for help about any UV Curing, UV drying.
UV Curing ink and uv led curing ink

IUV has many years of experience in the production of LED UV curing equipment. The UV LED curing products have received unanimous praise from customers.

The UV energy of the UV LED light source is as high as 25W/c㎡.  Widely used in UV offset printing machines and flexographic printing machines, satellite label printing machines and other large-scale UV printing equipment.

IUV is in a leading position in the industry and is deeply loved and praised by the majority of UV printing equipment manufacturers and UV printing customers.

Poor Gloss and Brightness
  • Low Viscosity and Thin Coating

Adjust viscosity and coating amount of UV varnish based on paper conditions.

  • Uneven Application of UV Oil

Ensure even application of UV oil.

  • Highly Absorbent Paper

Apply primer on highly absorbent paper before UV coating.

  • Excessive Dilution with Non-Reactive Solvents

Avoid excessive dilution of UV varnish with non-reactive solvents.

  • Insufficient Oil Supply from Anilox Roller

Opt for a thicker anilox roller or increase oil supply if needed.

Inability to Apply or Staining of UV Ink
  • Causes

  • Low viscosity and thin coating of UV varnish
  • Presence of excessive adjusting or drying oil in ink
  • Crystallization of ink surface
  • Anti-stick materials on ink surface
  • Thin rubberized anilox roller
  • Solutions

  • Apply UV ink appropriately and with sufficient thickness
  • Consider using primer or special ink for UV glazing
  • Address ink surface issues such as crystallization or presence of anti-stick materials
  • For high-quality UV curing solutions, use IUV’s LED UV curing equipment with exceptional UV energy output
Importance of Proper UV Curing

UV ink curing involves polymerizing monomers in the ink binder into polymers using ultraviolet light of different wavelengths and energies. This process is crucial for achieving proper drying, gloss, and adhesion of UV inks on printed surfaces.

Proper UV ink curing is essential to avoid these issues and ensure high-quality printed products that meet customer expectations.


  • Poor drying and stickiness

  • Lack of gloss and brightness

  • Inability to apply or staining


  • Affects print quality, handling, and further processing

  • Diminishes visual appeal and perceived quality

  • Causes defects, rejects, and potential customer complaints

Key Takeaways

Regularly check and maintain UV lamp intensity to ensure proper curing.

  • Monitor UV Lamp Intensity

  • Adjust Ink and Varnish Properties

Optimize viscosity, coating thickness, and dilution levels of UV inks and varnishes.

  • Address Surface Issues

Resolve any issues with ink surface, such as crystallization or anti-stick materials.

  • Consider IUV High-Quality UV Curing Equipment

Invest in reliable UV curing equipment like IUV’s LED UV lamps for optimal results.