Laser engraving, which is a subset of laser marking, is the practice of using lasers to engrave an object. Laser marking, on the other hand, is a broader category of methods to leave marks on an object, which also includes color change due to chemical/molecular alteration, charring, foaming, melting, ablation, and more. The technique does not involve the use of inks, nor does it involve tool bits which contact the engraving surface and wear out, giving it an advantage over alternative engraving or marking technologies where inks or bit heads have to be replaced regularly.
The impact of laser marking has been more pronounced for specially designed “laserable” materials and also for some paints. These include laser-sensitive polymers and novel metal alloys. Plastic security seals have a special additive impregnated in material which is sensitive to length wave of laser resulting the laser printing on plastic seals. Metal seals being made from metals and alloys that are heat resistant materials, marking them with laser requires a high-density laser irradiation. So the laser power leads to melting the metal and the peak power causes evaporation of the metallic material of the security seals.
The machines for laser engraving and laser marking are the same so that the two terms are sometimes confused by those without knowledge or experience in the practice.
Once the laser engraving is done on the security seals, being them plastic or metal seals, this is a permanent printing solution. The laser print is very resistant on chemichal fluids, schratches or other mechanical actions compared to the thermo tranfer printing solutions.
Aldo Security has in 14 laser marking units (YAG and UV) as a stand-alone unit or integrated into automatic stations.