Polycarbonate Stalled?

A major project announced in March 2005 to replace automotive glass with lightweight polycarbonate glazing has not yet gelled.

Cadence Innovations, the successor to the former bankrupt supplier Venture Industries, has planned a $30 million investment over the next six years in Czech Republic to produce polycarbonate glazing coated with a scratch-resistant “near-glass” layer. However, the company has not yet decided where to build its pilot plant. Last fall it expected to build the plant this year.

“We still have many internal discussions running, which are concerning PC (polycarbonate) glazing, especially the pilot project and its extent,” says Pavel Neuman, CEO of Cadence in Czech Republic. “This of course influences strongly the final decision about the location.”

At the Frankfurt auto show last September, Cadence and Inalfa Roof Systems, the Dutch supplier, showed a panoramic sunroof using polycarbonate louvers made with a scratch-proof process that Cadence has licensed from Exatec, a joint venture between resin suppliers GE Plastics and Bayer AG.

At the time, Inalfa and Cadence appeared to be developing a project sold to an auto maker.

This spring, however, Inalfa says the polycarbonate glazing remains in the testing stage.

“We want to be a little bit further in our development before we start publishing more about the subject, due to the relative negative experience with the products of some competitors,” says Eddy van der Vorst, Inalfa Roof Systems' business development director.

“With the negative press around those projects, we prefer to first develop our technology a little further and finish all the validation and testing,” he says

Van der Vorst did not elaborate on the negative experience or identify the competitors.

Polycarbonate, which can be molded into complex shapes, now practically is standard for headlight covers, but the first real incursion into traditional automotive “greenhouse” areas was the fixed rear window in the Smart Fortwo city car beginning in 1998. That window is supplied by Freeglass GmbH, a joint venture between Saint-Gobain Sekurit and Schefenacker AG.

Since then, Freeglass has supplied fixed side windows to the Smart roadster and Forfour (both now abandoned by Smart) and polycarbonate panels in sunroofs for the Mercedes-Benz A-Class and B-Class.

Freeglass last year began supplying its first component for a customer other than DaimlerChrysler AG: fixed rear windows for the Seat Leon that include a molded recess to access the handle for the rear door.

Concept-car designers like polycarbonate for its moldability. Engineers like the material for its strength and weight that is half that of glass.

This winter, Ford Motor Co. used it in the sunroof of the Aston Martin Rapide sedan shown at the Detroit auto show. At the subsequent Geneva auto show, Rinspeed's ZaZen concept used a 1-piece polycarbonate windshield-roof that resembled the bubble cockpit of an older jet fighter.

The material's main problem is its softness. Unless specially treated, polycarbonate scratches easily.

Freeglass has been using a wet-coat treatment in which the coating is applied like paint and cured. Exatec uses a plasma technique, in which a thin glass-like coating is applied in a vacuum chamber.

“The current leader in polycarbonate glazing is Freeglass,” Exatec CEO Clemens Kaiser tells Ward's. “They use a relatively well-known wet coating. There are well-known limitations to its resistance to abrasion and weathering that only Exatec 900 can meet for glazing. It extends the market potential (of polycarbonate glazing) because it enables windows and large roof systems.”

Exatec 900 essentially is the plasma coating process, which can be used on any part molded with a polycarbonate resin. Bayer markets its resin as Makrolon, and GE Plastic markets its resin as Lexan.

Kaiser says the first Exatec glazing will show up in 2008 or 2009, and “once it starts, you will see exponential growth.”

Exatec was formed in 1998 — the year the Smart Fortwo went into production — thus speedy adoption has been the paradoxical promise of polycarbonate glazing for almost a decade. Besides the problems of abrasion and durability, there is the problem of cost. Glass, while heavy, is faster and cheaper to manufacture.

In an article six years ago, then-Exatec President Doug Nutter said polycarbonate technology would never be as cheap as glass but still adds value.

“Let's just say doing the side glass in a vehicle costs an extra $150,” Nutter was quoted as saying. “For your investment, we can take 20 to 50 lbs. (9 to 22 kg) out of a car, we can offer colored glazing, styling freedom, modularization on encapsulated parts and protection from occupant ejection. That's a lot of value.”

Last fall, the National Highway Traffic Safety Admin. said polycarbonate could be used in vehicle windows if it meets the 10-year durability rules for glass, and Kaiser claims Exatec 900 does so.

Meanwhile, automotive trends seem to be moving in a direction to support PC growth. Big sunroofs and transparent roofs are becoming more popular at the same time concern about fuel efficiency is growing, which suggests weight savings, even at added cost, will have a higher priority again.

In North America, says Kaiser, PC roof systems are seeing limited success.

“The Japanese and Europeans are ahead on big roofs,” says Kaiser, but there are a few programs from North American OEMs, such as that for the Cadillac SRX.

“Where they are available as standard or an option they appear to be very popular with buyers, and they are increasing in popularity. There is more and more interest in a large roof with glass. Today they use laminates, which are heavy, and the shape is limited. Polycarbonate is half the mass of glass, and less than half compared to laminated glass,” Kaiser says.

Cadence Innovation has three plants in Czech Republic, in Liberec, Liban and Nymburk, now making plastic parts for auto makers. The pilot plant for its Exatec process is expected to be associated with one of those sites.

And Inalfa's van der Vorst says while “the quality of production and coating systems are not yet at the same level as where we will be,” the polycarbonate glazing in the roof module is now in the process of going though an intensive “Arizona Test” to validate its durability, the final step in persuading auto makers' purchasing departments to sign contracts.