NO FLASH IN THE PAN (Laser digital converting presents compe
Laser digital converting's efficiency and flexibility present compelling competition for conventional diecutting.
by Sue Friedman, Editor
WITH ALL ITS flashy trappings, laser digital converting technology could have been hyped to the max. The process, which actually vaporizes material in order to accomplish various finishing operations, is instead quietly edging toward mainstream applications. How deep a niche will it ultimately etch?
A typical laser digital converting system can include a CO2 laser, power unit, chiller, controller, software, smoke containment system, and web handling system (if not integrated into an existing press or finishing line). Camera-based vision systems may be needed for critical registration requirements. All in all, converters considering this technology should expect an investment to the tune of $180,000-$300,000—similar to the costs involved in a major prepress upgrade, notes John Dillon, VP/sales and marketing for LasX.
Older systems used a fixed laser with a moving x-y table underneath; some potential customers shied away from this technology because of speed limitations, relates Chris Chow, VP/converting at Laser Machining. Newer "galvo" systems (which employ scanning galvanometers) use steered beams and rotating mirrors to help the laser move faster. Typical processing speeds reported range from 80 ips to 600 ips.
A roll-to-roll laser system can be step and repeat, running with an intermittent or indexing motion, or cut on the fly, continuously moving as the laser follows the programmed pattern. Material is through-cut by adjusting the cutting speed to allow the beam to fully penetrate the material. By applying different laser parameters, material can be kiss-cut to a liner, scored to a depth, or perforated.
Tracing parameters and benefits
Laser digital converting harbors a notable array of benefits. From a flexibility standpoint, any programmed shape can be processed; lasers can cut in any direction. Die shapes can be changed on the fly, without tooling, offering potential for complete personalization of a run of packages or labels. Accuracy, too, is a digital system strong point. Laser converting is said to routinely achieve 3 mil tolerances, and can even compensate for inaccuracies inherent in the printing and finishing process. "Materials may stretch," notes Chow, "and lasers can adjust to this. A die cannot."