New Design for World s Best- Selling Sports Sunglasses

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1 Product Story No. 06, September 5,2008 New Design for World s Best- Selling Sports Sunglasses Optimal Framework Provided by Evonik s TROGAMID CX When the spring sunshine beckons and bicycles, inline skates, and walking shoes are pulled out of the closet where they ve been hibernating all winter, sunglasses are an indispensable accessory: Actually, 85 percent of Germans and two thirds of all Europeans own a pair. In the U.S., with its 300 million or so inhabitants, more than 350 million pairs of sunglasses are sold each year. And thanks to the latest polymer research, they keep pace with fashion trends. Contact

2 Product Story No. 06, Page 2, September 5,2008 Innovation in sunglasses can be achieved only via the material, says Rolf Obermeier, Managing Director of Alpina International in Friedberg, Bavaria. About 25 years ago his company set new standards with SWING functional sports glasses, of which more than three million pairs have since been sold. In a market where the customer can choose from thousands of models each year, SWING glasses remain the world s best selling functional sports glasses. Top Marks for Evonik Material On the 25th anniversary of SWING s debut, Alpina has launched the latest generation on the market: the SWING 44 and the somewhat slimmer women s model, SWING 33. As in the previous model, the frame, temples, and connectors are made from TROGAMID CX, a high-performance polyamide from Evonik Industries. Alpina has been using this plastic for more than six years on account of its high resistance to chemicals, stress cracking, abrasion, and UV radiation. It scores over its predecessor, polyamide 6, mainly in its higher light transmittance and a lower tendency to water absorption, which means that its excellent mechanical properties are retained even in high atmospheric humidity. For more than six years, Alpina has been using TROGAMID CX in the manufacture of the SWING s frames, sides, and connections, because this high-end material is tough against chemicals, stress cracking, abrasion, and UV light. This unusual property profile is due to the crystallinity of TROGAMID CX. Minute crystallites, known as microcrystallites, have the effect of mechanically reinforcing the polyamide. They are too small to be seen by the naked eye, however, so that the material appears crystal clear and transparent.

3 Product Story No. 06, Page 3, September 5,2008 Unlike other transparent plastics, therefore, TROGAMID CX combines the plus points of an amorphous and a semicrystalline polymer. The microcrystalline structure has the advantage that the positive features arising from the crystallinity, such as the stress cracking resistance, are retained without hazing of the material. The content of the crystalline component is so low, however, that it does not negatively impact the shrinkage behavior of the parts. That s what makes TROGAMID CX unique, says Klaus Hülsmann, Key Account Manager, Lifestyle, in Evonik s Performance Polymers Business Unit. The final assembly stage in Chamerau, Bavaria, Germany, where Alpina manufactures SWING goggles. The frame consists of twelve individual pieces, which are assembled by hand. Since TROGAMID CX can be easily drilled, ground, and milled, all parts fit together seamlessly. Design Without Limits Moreover, parts made from the high-performance polyamide are easily injection molded, drilled, ground, milled, and colored to any required shade, so that there are virtually no limits on design. Alpina exploits this advantage in a particularly attractive feature: by means of a filigree mechanism made of TROGAMID CX, the temple joint can be adjusted to five different inclinations. Wearers can therefore choose either to shield their eyes completely from drafts or to allow freer ventilation an option that, thanks to the mechanical strength of the high-performance polyamide, remains available for many years.

4 Product Story No. 06, Page 4, September 5,2008 The specialty polyamide has also brought about another design improvement: SWING has all-weather lens system consisting of two polycarbonate shields. Mounted on the fixed and light-tinted base shield, which allows undistorted all-round vision and screens out harmful UV radiation, is a second, dark-tinted covering shield that provides glare control. This can be very easily removed if, for example, the sun is obscured by clouds. In the previous model a metal push-button was used for this purpose, which has now been replaced by an almost invisible but equally stable solution based on TROGAMID CX. The frame, also made from the high-performance polyamide from Evonik, is in addition break-resistant, scratch-resistant, and non-allergenic. The high stress cracking resistance of the material means that the wearer can use perfume, sun creams, or cleansing agents without any problem. SWING, which weighs in at just 25 grams, is also available with optical glass lenses. Making the Choice Even More Difficult: A Wider Color Range for Lenses Barely was the new model ready when Martin Gehring, who is responsible for product development at Alpina, was looking at the next development stage - the expansion of the range of lens colors to afford even greater flexibility in color design. This could be realized by an injection molding production process of the type already used for frames. In contrast to the extrusion process that Alpina currently uses for lens production, injection molding allows rapid and efficient change of color even for small production runs, thus offering more design options. For sportspersons, engineering and function are of paramount importance. But the design must also be right, says Ronald Siller, head of marketing at Alpina. The injection molding process must first be worked out in the minutest detail. The process must be carried out in such a way that the one-millimeter-thick lenses have a thickness that is uniform and accurate to within one micrometer, and the surface is smooth and entirely free of streaks and air bubbles, is how Gehring describes the requirements. Because it s only in this way that the panoramic lenses attain the high Class I optical quality that is the norm at Alpina. They are then free from optical distortion even at the edges. Lenses that do not satisfy this condition could cause headaches in the long term.

5 Product Story No. 06, Page 5, September 5,2008 The filigree but robust mechanism made of tiny TROGAMID CX individual parts makes it possible to adjust the sides in five steps either toward the forehead to cut off drafts, or away from the forehead for ventilation. TROGAMID CX for More Reliable Performance Good experiences with TROGAMID CX and its excellent optical properties have taken this plastic to the number one position in the list of possible materials for injection-molded eyeglass lenses. Its advantages for optical applications include its outstanding light transmittance, high refractive index, and the high light transmission of 92 percent for a thickness of two millimeters. Additionally, the high-performance polyamide can easily be colored by mass coloration via colorants as well as by subsequent dip coating, and can also be provided with scratchresistant antireflective coatings or special filter functionalities. Fashion designers in particular have long used and valued TROGAMID CX as a material for lenses because it allows production of lightweight and robust sunglasses of very high quality in virtually any design, says Heinrich. At Alpina the first trials are already in progress. We can stay competitive in this market only by offering something special, time and time again, says Obermeier justifying the high investment in development and revealing the secret of the success of a product that for years has virtually been selling itself, despite ferocious competition from Chinese suppliers.