Laser engravings on plastic have to be of different and contrasting colour.

Plastic articles that can be engraved by laser usually have special thermal additives or are multilayered. Laser engravings on such articles are especially contrasting and of high quality.

Engraved area on light colored plastic usually looks black or gray. Sometimes special black paint, which absorbs into micro pores left by the laser beam, is used to make the contrast stronger.

The majority of dark coloured plastics used in computer industry that do not have special additives change colour under laser treatment. The colour contrast is usually good.