Volume 34, Number 1, January 1999


K ’98 Plastics Exposition German Plastics Expo

Highlights Auto and Fenestration Applications

by Walter Morham

There are plastics shows held every year around the world, in Japan, Mexico, the United States, Canada, Great Britain, but, there is only one K (for Kunstoffe) show held every three years and the whole world attends. More than 265,000 people attended K ’98 held at the Dusseldorf Messe from October 22-29. All 15 buildings were filled with processing equipment, materials and tooling. Visitors represented over 103 countries.


Resin and equipment suppliers were on hand to demonstrate the increasing level of plastic parts in new automobiles. Bayer (resin supplier) had on display a cut away of a complete autobody showing all the plastics parts for which they supply resin. Engel (injection molding machines) was demonstrating a new thermoformed/injection molded autobody panel.

General Electric displayed the European "MCC Smart Car" designed for faster urban transportation and built by Mercedes/Swatch. It is a first production application of tinted polycarbonate (PC) for a fixed side window, replacing glass, in the rear quarter panel of an automobile.

The General Electric and Bayer displays indicated that automotive applications were a major market goal of the joint venture GE Bayer Silicones. One of the primary market targets of the new company is automotive glass. Both General Electric (Lexan) and Bayer (Makrolon) are producers of polycarbonate resin.

While polycarbonate yields a tough clear sheet material, it has poor abrasion and scratch resistance and therefore, by itself, is not suitable for windshield or side door glazing applications. If, however, a hard coating could be applied to the PC sheet that would greatly enhance abrasion resistance, it would increase its technical acceptability as an automotive window glazing.

GE Bayer Silicones was demonstrating their line of existing "hardcoats" for polycarbonate and acrylics. Spokespeople for the company said research is currently being conducted to coat a plastic sheet material such as polycarbonate with a very thin film of silicon glass by a deposition method known as sputtering. It is a process whereby gas ions, accelerated by high voltage, bombard a source, i.e. silicon, in a vacuum chamber. Atoms from the silicon are deposited on the polycarbonate substrate and form a thin glass film. This research concept is only one of several experimental developments now in progress. Not only do they have to provide the required physical and chemical properties, they must be cost competitive. The K ’98 show displays demonstrated that major plastic resin manufacturing corporations are joining forces to raise the large amounts of research money and the talent needed to replace glass in a major market.

Why would a corporation spend large amounts of research time, money, and talent on such an application when standard auto glass has such a traditional commanding market presence? The answer lies with an untapped new market, large volume and a competitive advantage — weight reduction. The future of plastics is as a substitute for traditional materials — wood, metal and glass.

As much as 75 pounds in weight could be saved by the substitution of plastic for glass in the average four-door sedan.

Weight reduction improves gas mileage. Federal and state governments are pressuring automakers to meet higher gas mileage and lower emissions limits. On the average 13 to 17 million cars and trucks are sold in the U.S. market annually.

At K ’98, there were many automotive and window glazing applications of "silicone hard coat" on display illustrating the broad application of plastic coating technology to provide abrasion resistance. Both polycarbonate and Acrylic (PMMA) substrates are used.

• Polycarbonate glazing for nursery greenhouses, protected exterior walkways, shopping malls, building entrances, kiosks, office room dividers.

• Polycarbonate for auto headlamps, fog lights, and sidelite glazing.

• Acrylic for outdoor signs, auto/truck rear brake & backup lights.


Ensinger Technische Kunstoffe GmbH & Co., Nufringen, Germany is utilizing pultrusion technology for the manufacture of high quality security window and door lineals. Pultrusion is a manufacturing process by which continuous fiber reinforcement is drawn through a thermosetting resin bath and pulled through a heated die to form lineal profiles.

Ensinger displayed a variety of high strength, thermal insulating, glass fiber reinforced pultruded lineals in different shapes together with a cut-away of an actual window. Pultruded lineals are used to replace aluminum as internal slide components. Pultruded lineals are generally not used for exterior window components because they do not have a fine smooth surface.

New tooling designed to speed up extrusion production line changeovers was on display. The concept is ideal for a line used for short production runs. Emil Lihotzky Maschinenfabrik GmbH & Co. Plattling, Germany is marketing an extruder tool die changer modeled on a horizontal slide screen changer. It allows a die to be changed in three seconds. A complete changeover including moving downstream equipment into place, such as the calibration unit, can be accomplished in five to ten minutes. For profile extrusion the calibration unit has to be modified to a quick-change setup, so it can be shifted into exact position consistently.

Twin and triple wall sheet has been extruded using Polycarbonate, and Polyethylene Terephthalate (Glycol) (PETG) for some time. Previously, straight Polyethylene Terephthalate has consistently resisted twin wall sheet extrusion because of its heat characteristics. Straight PET flows like water.

Politec-Polimeri Tecnici S.A. of Switzerland exhibited a clear twin wall extruded sheet of straight PET under the trade name Macrolite. An ultraviolet (UV) stabilizer is compounded into the PET resin to keep the sheet from yellowing with age. It is produced by Sukano Products Ltd. of Switzerland.

This new development is of particular interest to builders using extruded clear twin wall sheet for interior applications. An example is as a replacement for glass or PC room dividers or partitions in offices or homes. The current price of Polycarbonate extrusion grade is $1.71/lb., Polyethylene Terephthalate G (PETG) is $0.98/lb. and straight Polyethylene Terephthalate (PET) is $0.50/lb. The potential savings in material costs are significant with no decrease in strength or clarity.

Walter Morham is vice president of the International Plastics Consultants Corporation (IPCC) in Stamford, CT. IPCC is a consulting organization that serves the plastics processing industry.


Copyright 1999 Key Communications, Inc. All rights reserved. No reproduction of any type without expressed written permission.