Scientists at Bayer Polymers in co-operation with Swiss company Lumitec AG have succeeded in producing the first illuminated plastics parts. The plastics mouldings are produced in a single step to create an all-in-one, operational component, without the need for multiple assembly. A printed film made from a blend of polycarbonate and polybutylene terephthalate forms the ‘smart’ outer skin of the plastic component, which generates light when a voltage is applied.
‘This new development means we can meet the car industry’s desire to optimise the layout of car interiors with ‘ambient’ lighting so that drivers can find their way around,’ says Eckard Foltin, Head of the Creative Centre in Business Development Bayer Polymers. The concept behind the light source is more or less the opposite of a solar cell. The film is moulded over a multilayer electrode system, which uses electroluminescence to generate cold light on application of a voltage. The main focus of the development lay in the fact that the printed film could first be moulded and then, in a second stage, back injected with a thermoplastic, increasing its range of possible applications.
In addition to control panels, pictured, there is also scope to use the technology in other instrument panel elements in car interiors, as well as in door sills and other optically important components.
Some production examples include:
• The luminous rear registration plates on the Volkswagen Phaeton
• The sill plates with bright shiny logos on the BMW Z4
• The tachometer dials in the Mercedes E-Class which glow white in the dark
The process can operate on conventional batteries, and the light varied according to the voltage applied, which means the illuminated plastics moulded parts can also be put to good used in other applications, such as control panels and switches fitted to household appliances. Bayer Polymers are also looking at applications in which the illuminating feature can be used in handbags, suitcases, rucksacks and deep freezes. At this stage the scope of potential applications is endless, and because the plastic components are waterproof, the parts could be used in wet-process rooms or at the swimming pool.