Spot UV Problem - Double Sided Spot UV

[herbert]

Hi All

Here goes, ill try and explain the issue's.......

- B1 Sheet - 4/4 Spot UV Both Sides - Flexo Plates used for Spot UV
- 1 pass per Side
- The Sheets are printed on a Heidelberg CD102 6col with Dual Coating Units.
- Conventional Ink Set (We dont want to use UV inks)

The problem, when the Sheet are in the pile we found that when the Ink came into contact with UV from the reverse side, the Ink started to peal off leaving marks - The Job was rejected..I must say the Job looked great except for the Marks!!!!

I think the heat from the spot UV side was heating the ink up again causing the ink to set off (is this the right terminology?)

Based on what iam stating what is the best way to print such a Job

Any questions fire away.i think ive covered everything !!!

 

[uscollins]

Good luck if you are not using UV ink. If you are forced to use conventional, and it sounds like you are, allow the first side enough time to dry.

Also, check for proper drying of the spot UV, air knives, lamps etc. Also, reduce run speed to see if that helps your coating set. If the UV is not drying properly, and air knives and lamps are correct, engage your coating representative. We have had similar issues and Kelstar Actega (our coating supplier) came on-site with new formulations until the problem was fixed.

What don't you run UV inks? Press? Cost? Rollers and blankets?

JC