Automotive Industry Trends
July 2005
Automotive Glazing: Like Sci-Fi Today, to Market Tomorrow
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Automotive glazing is poised to become a technological marvel that only a short time ago would have looked and sounded like science fiction. Advancements in design, nanotechnology, and materials science will allow car makers to create glazing profiles with never-before-seen capabilities.
Materials innovations will give designers the freedom to accomplish what until now has been thought impossible. One of the key assets in this progress is polycarbonate. Although polycarbonate is more than 50 years old, for the purposes of auto glazing, it is only now about to come of age. The thermoplastic is desirable for its high impact resistance, its light weight, and its ability to be molded into almost any shape.
Designers are expanding the area of the vehicle that is made up of glazing to dramatic effect. Some renderings look almost like an open carriage, with virtually the entire top half of the vehicle made of glass. A foremost obstacle to this “open-to-the-sky” design has been the weight of such a large amount of glazing. Polycarbonate may reduce that weight by 50 percent, in side windows, rear windows, and panoramic sunroofs. (Current U.S. regulations do not permit the use of polycarbonate for windshields.) Polycarbonate allows imaginative sculptural effects, giving vehicles ever more distinctive looks.
Until now, the promise of this compound has been blunted by limits of abrasion-resistance and weatherability. However, plasma technology is on the verge of a solution—a glazing layer with a glass-like plasma topcoat with superior abrasion properties and a 10-year weathering life. Nanotechnology, using nanoscale additives to create compounds with entirely new properties, will also play a significant role in tomorrow’s emerging technology, for example, improving the scratch-resistance of topcoats with microparticles of silicon dioxide.
Polycarbonate’s other drawback is cost. As a technology based on oil, it will always be more costly to manufacture than sand-based glass. However, there will be a tradeoff. Reducing the weight of vehicles by the use of polycarbonate for glazing will significantly reduce fuel costs for consumers, especially as more of the car’s surface is devoted to glazing.
At one time, the unassuming windshield was a nothing more than a barrier between the driver, the rush of air ahead, road debris, and the occasional insect. The glazing on future cars will perform far more sophisticated tasks. In addition to light and heat absorbance and reflection and UV protection, light transmission through the glazing will be controlled with the turn of a knob or left to automatic dimmers. Electrochromic (EC) glass will be manipulated by choice, providing dimming by 40 percent to as low as 2 percent.
Competing with EC for a place in the market is the quick-reacting suspended particle device. SPD works through a thin film sandwiched in the interlayer that conducts low-voltage electricity. As the current passes through it, suspended particles either gather or disperse, allowing more or less light to pass, ranging from totally light to completely dark when the car is shut off and the current is cut.
Also integrated in the interlayer will be a nearly invisible set of antennas no thicker than a strand of spider’s web. The antennas will provide communications links for Telematics devices for Internet, cell phones, navigation, and entertainment.
Another feature ready now for adoption by auto makers is a hydrophobic windshield coating. This safety innovation prevents water drops from splattering when they hit the glass. The drops remain spherical and simply fall off the vehicle.
These and other developments in automotive glazing will allow manufacturers to transport stunning designs from minds of today’s designers and scientists to the real-world showrooms of tomorrow.
The total area of an automobile that is made up of glazing has increased since the days of Ford’s Model T. With increased area has come added weight. A mid-range car in 1990 might have carried 85 pounds of glazing, whereas today it could be as much as 100 pounds or more.