Electroluminescent lamps facilitate 'light-effects' on paper
prelonic, an Austrian company, has been working on an electroluminescent lamps (EL) technology to enable the printing of 'light-effects' directly onto paper and cardboard via conventional printing processes working in a regular printing environment. According to the company, applications of the technology include flashing lights on packaging, illuminated magazine covers and books with 'highlighted' areas.
Friedrich Eibensteiner, founder of the company, stated that there are still some critical technological barriers that need to be overcome. "It is not the printed lamp, that is an old and mature technology, it is the driver and the integration, which are really challenging," said Eibensteiner. "Most of the parts are already printed and fully integrated. The lamp, connectivity, switch and battery are printed directly to the paper or cardboard. But with the driver, we are only half the way there. Most parts of the driver are already printed. However, some are still under development. And we are working on miniaturization, because at the moment, the area is more than an A5 sheet of paper. In the end it will come down to a fully printed driver and few square centimeters."
Eibensteiner believes electroluminescence still seems to be the only light technology that can be printable and will be available in the next years with reasonable effort. Although LEDs are available, Eibensteiner points out that they are not printable and they still require pick place processes. LEDs also only produce small light spots, even if they are robust and bright. OLEDs offer area lighting, but are not suitable for the printing applications for a number of reasons including the need for clean room processes, encapsulation and high costs.
Full development and roll-out of EL printing on paper will take some time, said Eibensteiner, but he reckons after that a cost efficient technology for lights on magazines, books and packaging will be available.
prelonic expects the first EL printing applications will be hybrid ones because the driver is still not fully developed. But prelonic has realized a solution that enables printing by using most of the driver components that can be completed with few simple conventional printing functionalities.
The hybrid approach could enable conventional screen printing in a normal paper and cardboard environment to be achievable, which is a pre-condition for low cost mass production.
- Paul Buckley
EE Times Europe