Which defects matter most on a flexible-packaging web
On flexible packaging the defects that matter most are dirt and pinholes in the heat-seal zone, the barcode, and missing or wrong text that would mislead. A small spot in a decorative solid follows the dirt table. A heat-seal defect can leak. Do not use the same release scale as ordinary dirt.
On flexible packaging the defects that matter most are dirt and pinholes in the heat-seal zone, the barcode, and missing or wrong text that would mislead. A small spot in a decorative solid follows the dirt table. A defect in the heat-seal zone can leak. Do not use the same release scale as ordinary dirt.
Why it is judged this way
A white spot on film may be missing print, or it may be a lamination bubble. Both look like one spot. Separate the regions first: a spot on the seal band is stopped and looked at, a spot in the middle of the design follows the table. If it is not on the table, keep the sheet and ask the customer.
What to compare
| What you see | Call it | Do not |
|---|---|---|
| Dirt or a bubble in the heat-seal zone | Stop and look. Do not release it straight away | Use the scale of a decorative solid |
| A broken barcode bar, or a quiet zone that is occupied | Cannot be released | Let it pass because a scanner still reads |
| A small white spot in the middle of the design | Follow the dirt table | Write a millimetre number of your own |
Check at a job change or a new roll
- On the template, mark the heat-seal zone and the barcode, and keep their sensitivity apart.
- Try the alarm with one dirt spot on the seal band.
- If the grade is not clear, keep the sample. Do not ship it first.
