How to inspect a shrink sleeve without stretching the measurement
Measure the print and the barcode of a shrink sleeve while it is still flat, before it shrinks. Do not measure the size after it is on the bottle. Shrink pulls the barcode and the register out of shape. That distortion is not a print defect, and it cannot prove the print was accurate.
Measure the print and the barcode of a shrink sleeve while it is still flat, before it shrinks. Do not wait until it is on the bottle and shrunk, and then measure the size. Shrink pulls the barcode and the register out of shape. That distortion is not a print defect, and it cannot be used to prove the print was accurate.
Why it is judged this way
The circumference of a sleeve shortens. If the barcode grade on the press is the basis for shipping, measure it on the flat roll. The check after the sleeve is on the bottle only answers whether it sits skewed or has a severe wrinkle. Write the two conclusions apart.
What to compare
| What you see | Call it | Do not |
|---|---|---|
| You must prove the printed barcode | The flat roll, before shrink | Grade it after it has shrunk |
| You must prove the sleeve position | After it is on the bottle | Substitute print register for that |
| A slight distortion from shrink | Do not record it as print ghosting | Send it back to the press |
Check at a job change or a new roll
- The release numbers for the barcode and the register come from before the shrink.
- The bottle station only looks for skew, splits, and severe wrinkles.
- Do not merge the two records into one pass.
