Both the 1µm and 10.6µm wavelengths can be used for laser marking plastics. Which laser to use is determined by the type of plastic.
Cast acrylic is best processed by a 10.6µm laser where it is possible to engrave with some depth. Extruded acrylic does not mark with much contrast because of its lower melting point.
Some acrylic laminated materials exist where removal of one layer reveals a different coloured layer underneath. Such materials come in special versions for laser processesing and should be used in preference to a standard variety.
Polycarbonate is best processed by a 1µm laser where it is possible to mark with very high contrast (black). ABS is a commonly marked plastic, especially in the electronics industry.
Some plastics, such as Polypropylene will not mark without the addition of a laser enhancer during the moulding process but when such enhancers are added the results can be extremely good.
Acrylic is by far the most commonly used plastic for laser cutting where the 10.6µm must be used. The resulting cut is fast and accurate to produce.
Compared to other cutting technologies the laser process produces minimal by-product and allows for unique advantages such as a polished edge and the ability to cut with the protective films intact.
Other plastics, such as polycarbonate or polypropylene for example, offer cutting possibilities limited to material thickness because of adverse reactions to the heat of the 10.6µm laser increasing with the thickness of material.