How to inspect a clear-on-clear print on transparent material
A clear-on-clear print on transparent material often cannot be seen in straight light. Use backlight to bring the artwork out. If the outline cannot be seen, do not start the template.
A clear-on-clear print on transparent material often cannot be seen in straight light. Use backlight to bring the artwork out. If the outline cannot be seen, do not start the template. After the backlight is stable, look for broken lines and dirt as ordinary defects.
Why it is judged this way
A transparent label with little varnish or white ink disappears in front of a white background. With the camera facing a white roller, the view is almost empty. With backlight, the type becomes a dark outline, and a missing stroke can be seen. Running a clear job with the front-light settings used for paper is the same as not inspecting.
What to compare
| What you see | What to call it | What not to do |
|---|---|---|
| The view is almost empty | Add backlight first | Turn the sensitivity to the maximum |
| A missing stroke under backlight | Stop it as missing print | Pass it because the material is clear |
| The backlight flickers | Fix the lamp first | Redo the print |
At job change or when a roll is opened
- When the job changes to clear, look first for an outline in the view.
- If there is none, change to backlight. Do not move the threshold.
- Use one missing stroke and confirm the alarm.
