UV Coating Planning Tips

The UV Coating process is constantly evolving...

This guide is intended to be your most comprehensive guide to the UV Coating process at Apex. Bypassing or failing to acknowledge any of the following specifics will undoubtedly result in unsatisfactory UV Coating. Accordingly, we cannot accept liability for unsatisfactory UV Coating found to be the result of neglect of any of the following, standard procedures as they relate to UV Coating at Apex Die Corporation:

  1. Inks should be free of paraffin waxes, silicones or other slip additives. UV Coatings do not adhere properly to such. Also, avoid inks with alkaline pigments. Alkaline pigments are found in Reflex blue, Rhodamine red, PMS purple or any dark blue-to-violet color ink, regardless of pigment. Although these inks can normally be coated, they have a tendency to bleed and can cause the overall color to change significantly. Contact your ink supplier for availability of inks without alkaline pigments. If you are concerned about a 'marginal' ink, send us a printed sample in advance of the actual job, and we will test coat it for you. Please note: Apex cannot accept liability for unsatisfactory UV Coating found to be the result of ink or compatibility problems; we have no control over the ink application and resulting issues.
  2. Spray powder on a printed sheet will only be intensified by the UV coating process and will give the sheet an undesirable 'sandpaper' effect. If spray powder must be used, use only a minimum amount of any uncoated, small particle powder (30 - 50 micron). To further minimize the problem, a 'dusting' or 'dead-heading' pass on an offset press is highly recommended.
  3. Apex has installed a sheet cleaning unit to minimize the problem associated with spray powder on the sheet. As always, spray powder applied during the printing process should be absolutely minimized, however the addition of the sheet cleaning unit will relieve some of the undesirable 'sandpaper' effects (see note 2).
  4. Inks must be completely dry before UV Coating. Normally, 24 to 48 hours should elapse before coating. If emulsified at all, additional time may be required to ensure their dryness. Additionally, if the job is to be coated on 2 sides, an extra day should be scheduled between the coating runs.
  5. UV Coating should be applied to a smooth stock with a clay or enamel coated surface. No uncoated stocks. Cast coated stocks such as Kromekote should also be avoided.
  6. Any scoring required on a job should be done after the sheets have been coated– not before.
  7. Most foil stamping (including foil embossing) can be coated over. However, coated sheets normally cannot be foil stamped.
  8. Optimum stock thickness for UV Coating is .0045 and up, especially if it requires folding. Lightweight stocks tend to curl up and may crack when folded.
  9. Normally leave job in press sheet size. Do not trim before coating. This is particularly true if pattern or 'spot' coating is to register to printing. Also, be sure to clearly mark the gripper and guide on a sample sheet.
  10. Supply a clearly defined rule-out or film positive of the area to be coated. When supplying a film positive, the areas of the sheet to be coated should be black on the film, leaving clear the non-coated areas of the sheet.
  11. Due to the 'deep mirror-gloss finish' that UV Coating gives, it also has a tendency to reflect fingerprints on the finished piece when dark, solid colors have been used. Try to avoid these colors whenever possible.
UV printed and coated paper can be recycled into tissue and/or fine paper grades using commercially available equipment.