Controlling the position of printed artwork relative to the packaging operation, such as aligning a preprinted web with the blister layout and cutting position.
Also called: print mark registration; eyemark registration; print alignment; eye mark control.
What does a registration mark tell the machine?
An eyemark or contrast mark provides a positional reference for an operation such as printing or cutting. It relates artwork to the machine operation; detecting the mark does not identify the product contents or verify the printed information.
State which mark or pattern is used and which downstream position it references on the proposed blister layout. The mark-to-operation relationship belongs with the format drawing. Detecting a mark somewhere on the web does not establish that the printed panel sits correctly on every finished card.
A contrast sensor can respond to other artwork in its scan path when the intended mark is not sufficiently distinct. Changes in web tension can separately alter repeat geometry and alignment. An extra or missed reference signal and a stretched repeat are different issues to investigate.
Investigate an offset using the artwork, sensor path, web material and running conditions. Sensor response and material stretch need different evidence, so a repeated offset alone does not identify which caused it.
Does good registration verify the printed batch code?
No. Positional registration and information verification answer different questions. A reference mark can be correctly aligned while other printed information is missing or incorrect. Specify which system, if any, verifies the required content and readability; an eyemark detector alone is not that evidence.