There are a few possible reasons why you might be seeing ink marks on both sides of an offset printed sheet after it has been laminated. One possibility is that the ink was not completely dry before the lamination process began. This can happen if the printing press was not running at the correct temperature or if the ink was not applied correctly. Another possibility is that the lamination roll was not cut properly. If the roll is not cut flush, it can leave gaps between the sheets of laminate, which can allow the ink to bleed through. Finally, if the laminated sheets were not stored properly overnight, the moisture in the air can cause the ink to reactivate and bleed through the laminate.
To troubleshoot this issue, you can try the following:
- Check the printing press settings to make sure that the temperature is correct and that the ink is being applied properly.
- Make sure that the lamination roll is cut flush.
- Store laminated sheets in a cool, dry place.
If you have tried all of these things and you are still seeing ink marks, you may need to contact the manufacturer of your lamination machine or the printer who produced the sheets for assistance.
Here are some additional tips to help prevent ink marks from appearing on laminated sheets:
- Use high-quality inks and laminates.
- Make sure that the printing press and lamination machine are properly calibrated.
- Store laminated sheets in a cool, dry place.
- Inspect laminated sheets carefully before using them.