How to Engrave on Plastic by 355nm laser

Methods of laser marking on plastics

Foaming

Foaming leaves a tangible mark on the material. It can be seen as laser-induced boiling, which melts the surface. Due to the rapid cooling, bubbles are encapsulated in the material. These bubbles leave a positive mark, which is tangible.

The laser works on a low power level and longer pulses. Foaming works on all polymers, but also on some metals. Depending on the material the mark is light or dark.

Carbonizing

Carbonizing enables strong contrasts on bright surfaces. During the carbonizing process the laser heats up the surface of the material (minimum 100° C) and oxygen, hydrogen or a combination of both gases is emitted. What's left is a darkened area with higher carbon concentration.

The laser works with lower energy, which leads to slightly longer marking times compared to other processes. Carbonizing can be used for polymers or bio-polymers such as wood or leather. Since carbonizing always leads to dark marks, the contrast on dark materials will be rather minimal.

Color change

Color change on the material