This laser marking example was produced to exaggerate the contrast levels that can be obtained when plastic has laser receptive additives. The end user was a little sceptic regarding laser marking, so we had to do something to grab his attention. The product would not normally be marked in this fashion, however, contrast is always a primary requirement.
The result was to spend time developing a process and equipment for a plant in Ireland. The equipment was able to automatically handle and laser mark a wide range of plastic devices. Mark data included company branding, ID numbers and traceability details.
There are a number of differing changes to the material surface during laser marking and it is very dependent on the material itself as to which one occurs.
- A thermochemical foaming, creating gas bubbles to the surface of the material, is the most common. The light scatters across the affected area producing the light marking that appears.
- Bleaching is another effect that is common. Here the pigment used to achieve the product colour is removed creating a visual difference.
- The third mechanism is vaporisation where the material is heated, very quickly, to the point where it vaporises and is removed leaving behind the created image.
These three laser marking effects can be enhanced by the adding of laser sensitive additives and can generate considerable advantages. The additive acts as an abortion barrier, boosting the ability of the laser to process better. In some materials, the laser marking ability would not be possible without this additive.
CO2 could be used for the plastics, while it will mark the materials, it creates little if no contrast without additives, as it would be unable to mark ceramic components.
If you would like further information on this laser marking application, or any other application, please request a call back or talk to one of our laser marking specialists on 01737 826902.