Another solution for printing on glass, laser marking produces permanent high-resolution codes on nearly any color or type of glass. The permanent marks protect codes from being tampered with by unauthorized channels. Moreover, the high quality marks enable clear coding and help instill brand confidence with customers.
Laser marking systems like the Videojet 3640 CO2 laser and Videojet 7810 UV laser produce micro cracks that etch into the glass surface to produce serial numbers, internal tracking numbers, and traceability information on clear and colored glass.
When a laser places a code or mark on a plastic surface, it does so by using high heat to melt the plastic material, ablating (removing) part of it and leaving a mark in the surface. By thus altering the surface, the laser leaves a mark more permanent than a printed one that can be altered by being placed on a wet bottle surface, washed away during processing or damaged by abrasion during handling.
When a laser hits glass, however, the result is completely different: the glass fractures. Natural grains and crystalline structures in the surface, when heated very quickly, will separate a microscopic sized “chip” from the surface as the hot piece expands rapidly relative to its surroundings. In this way, lasers are used to etch or engrave on glass, and if the power, speed and focus are all well controlled, excellent results can be achieved.