Meaning
A precise material modification process uses a highly concentrated light beam to mark, engrave, or alter the surface of a plastic component or steel injection mould. Implementing laser etching on plastic parts allows for the permanent marking of serial numbers, bar codes, or branding directly on the polymer surface without using inks or solvent-based chemicals. This technique provides high-contrast, durable markings that resist wear, chemicals, and environmental exposure.
Polymer Interaction
Success of the process depends on how the specific polymer absorbs the wavelength of the laser beam. Amorphous resins like ABS and polycarbonate respond well to laser energy, often changing color through localized carbonization or foaming to create a high-contrast mark. Semi-crystalline resins like polyethylene or polypropylene often require special laser-marking additives to achieve the same clarity, as they tend to melt rather than change color.
To achieve the desired contrast and depth, the operator adjusts the laser’s power, speed, and frequency to match the resin’s thermal properties.
Process Control
Precise control of the laser parameters is necessary to prevent surface damage or degradation of the underlying polymer structure. Excessive laser power can burn through thin-walled parts or cause micro-cracks that weaken the component. Consistent calibration of the laser focus and scanning speed ensures uniform marking quality across high-volume production runs.
Surface Finish
On the steel mould itself, this process can create micro-textures that are transferred to the moulded part during injection. This allows for the direct creation of matte finishes or decorative patterns. It eliminates the need for secondary texturing steps.
