Roll-to-roll processes have uses in rapid, cost-effective electronic parts manufacturing, and have long been involved in electrical engineering, micro-production, and solar technology. Conventional and other laser-based manufacturing processes have already been incorporated in roll-to-roll manufacturing, but attempts to integrate direct structuring operations conducted using pulsed lasers have so far met with little success. Until now, these processes have failed because of inadequate repetition frequency and low pulse energy, as well as the lack of speed and precision of the beam deflection.
Recognizing this, the Fraunhofer Institute for Production Technology (IPT; Aachen, Germany) is collaborating with the Fraunhofer Institute for Environmental, Safety and Energy Technology (UMSICHT; Oberhausen, Germany) and partners from industry to develop a module capable of direct laser microstructuring in a roll-to-roll process. The aim of the project, dubbed PoLaRoll, is to produce a sieve-like metal foil to serve as a demonstrator that will be used to protect glass facades from the effects of the sun. Their special geometry will lower the impact of solar radiation, thereby reducing the amount of energy required to cool and ventilate the building.
In this project, Fraunhofer IPT is responsible for developing the laser structuring process as well as the measuring and systems engineering. In addition, the industrial partners will refine two pivotal components: a femtosecond laser with high power output coupled with an extremely high pulse repetition rate and an innovative, dual polygon scanner system, whose purpose will be to ensure swift and accurate beam deflection. Fraunhofer UMSICHT is developing a new chromate-free, environmentally compatible coating that will be cured via UV lithography. It will ultimately be possible to structure both sides of the metal foil simultaneously using a laser.
|Laser structuring of metal foil. (Photo: Fraunhofer…