Hidden on the inside of a bottle cap you will often find laser-marked characters and codes, e.g. production data. An end-user might be much more interested to look “under cover” once there is a code to be found for participation in a sweepstake.
The crown caps shown here have been marked using the color change method with a 100-watt fiber laser or a 60-watt CO2 laser. The inside paint-coated colored area was laser marked with a paint removal process.
If the cap itself or the coating on the inside of the crown cap is made of plastic, UV or CO2 laser marking systems are used. In any case, the laser-marked characters are pin sharp and food safe, durable and tamper-proof.
Usually, bottle caps are marked at high speed in the “marking-on-the-fly” method on a continuous line. The connection of the laser marking system to a production data environment makes it possible to label serial characters, numbers or codes continuously.