Makers of modular automobile windows - assemblies of sheet glass and hardware overmolded into a single part-are adopting new materials and process technologies to win a bigger share of business from automakers. A new study by ITB Group Ltd. of Novi, Mich., predicts strong growth for the $650 million modular window market. The research group says window manufacturers are making strong gains in cost reduction and part consolidation.
Donnelly Corp. of Holland, Mich., was one of the first firms in the market when encapsulated windows began appearing on cars in the early 1970s.
John F. Donnelly, senior vice president for modular window systems, expects the market to grow to $1 billion by the end of the decade. Part of that growth will be driven by greater integration of windows with surrounding body trim or hardware.
``We are expanding from encapsulated glass to full window systems,'' Donnelly said.
Modular windows, manufacturers say, provide a number of benefits compared with conventional window systems, which are still in widespread use in the industry. Because modular windows are installed as finished products, often with robotic tools, they can reduce the need for inventory, trim labor costs and speed assembly.
The windows are built of sheet glass and a plastic molding, usually PVC or reaction injection molded polyurethane, which encapsulates a number of components such as the frame, grommet, trim and hardware.
Conventional window systems consist of a frame and window glass, which are installed at the automobile assembly plant.
More and more hardware is being molded into the modular window. Window makers are incorporating hinges into the molding, introducing flush-surface windows encapsulated on the inside surface, bonding hardware directly to glass and even molding color-matched body trim into the finished piece.
Libbey-Owens-Ford Co. of Toledo, Ohio, makes both conventional auto glass and modular windows. The benefits of modular windows are greatest when the supplier's design engineers are involved at the earliest stages of product development, said Richard A. Sahler, original equipment marketing director.
That way, a maximum of product features can be incorporated into the modular design.
``The more you can do to that part while you're in the mold, the better off you are,'' Sahler said. Modular windows ``can be made to do a multitude of things,'' he added.
The trick is to convince original equipment manufacturers that the higher cost of modular windows offers a real payback in manufacturing efficiency and long-term reliability.
There is also concern about the aftermarket replacement cost for modular windows. The retail price for a lift-gate window on the four-door 1995 GM Mini-Blazer ranges from $640-$1,000, depending on the type of glass tint and hardware needed.
Still, the growth in resin consumption in the modular window market is evidence that molders are grabbing a bigger share of the business.
The ITB study said modular window makers in the United States and Canada consumed 11.4 million pounds of PVC and 17.8 million pounds of RIM PU in the 1994-model year. During the past five years, PVC use has been growing at an annual rate of 7.4 percent and RIM PU at an annual rate of 4.1 percent, ITB said.
Of the two dominant molding materials, PVC is cheaper and does not require painting. But PVC can be difficult to mold, particularly on larger windows.
Reaction injection molded PU, on the other hand, is of two types: aromatic and aliphatic. The aromatic needs to be painted, usually through an in-mold coating process, to improve weatherability. The aliphatic, which is increasingly preferred, is more stable and does not need to be painted, ITB said.
Several companies are working with ethylene propylene diene monomer rubber, long used to seal roll-up windows, for molding modular windows.
Earlier this year, Kingston-Warren Corp. and General Motors Corp. announced a joint project to develop a glass run channel and an EPDM-encapsulated quarter-window module. Production of the windows, which is set to begin for the 19961/2-model year, uses technology developed by two German companies: Saar-Gummiwerk, a rubber supplier, and Pfaff GmbH, a supplier of window encapsulation molds.
Kingston-Warren, based in Farmington Hills, Mich., is investing $3.5 million in new production equipment at its Churchill, Tenn., plant to prepare for production of the EPDM-encapsulated windows by mid-1995.
Compared to PVC, the thermoset EPDM material makes a better seal, looks better and has none of the environmental drawbacks, claims Brian Benninger, vice president of sales, marketing and product design at Kingston-Warren.
``There will be a major shift,'' he predicted.
At Excel Industries Inc., production is under way for a RIM PU-encapsulated windshield for the all-new 1995 GM J-car. The Elkhart, Ind., company uses both RIM PU and PVC and foresees continued acceptance of the materials, said Joseph A. Robinson, chief financial officer.
Robinson said he does not see ``as much pressure here in North America as in Europe'' to find substitutes for PVC.
