It's What's Inside That Counts

By Ellen Wuagneux, Associate Editor | December 8, 2005

nonwovens play expanding role in automotive interiors

These days, if you were to ask an OEM in the auto industry what’s under the hood, the answer would probably be “a nonwoven.” These materials now serve in an amazing array of automotive interior applications, a trend that began several years ago with nonwovens’ initial role as replacement materials in head, hood and trunk liners as well as in flooring, filtration and seating applications.

Today, spunbonded, stitchbonded, needled, thermal and binder bonded nonwovens are used as foam replacement materials in seating applications and as substitutions for PVC film in decorative interior end uses such as headliners, package trays and luggage covers. Nonwovens are also being used in moldable trunk, wheel arch and acoustic air duct systems as well as for insulation and heat shield purposes. Automotive tufted carpet reinforcements also feature nonwovens, as well as trim part alternatives, headliner facings, auto cabin air filters, self-supporting roof liners and rear shelf, sunshade, sun visor, seat back and seat cushion applications.

In the area of acoustics, nonwovens serve as both sound absorption and insulation materials and are meeting recent demands for lighter weight, acoustically tuned, underpads. These are replacing heavy weight EVA-type barriers. “Nonwoven acoustic packages are a clear trend for auto interior applications,” stated Yan Chen, associate professor at Louisiana State University, Baton Rouge, LA. “This means that nonwovens can be considered everywhere in a car for acoustic performance enhancement.”

At Precision Custom Coatings, needlepunched fabrics are being used as an acoustical component in headliner composites. “We have also made some exciting stretchable thermal bond nonwovens, which are being accepted extensively in the hoodliner market,” added Dan Kamat  PCC’s vice president Industrial Textile Division. “These products are made on our new line and have a 1:1 MD/CD ratio for tensile and elongation values.”

Freudenberg is the world’s leading supplier of automotive air cabin filters, shown here above in a variety of sizes; Pictured below is an example of an automotive interior headliner facing application from eswegee Vliesstoff GmbH.

German roll goods producer Sandler offers PET-based sawasorb nonwovens that offer sound absorption benefits. The materials cover almost all applications for acoustically effective components in the automotive industry and are found in more than 30 vehicle models throughout Europe, according to the company. For visible applications, all versions in the sawasorb family are also available in dark anthracite and are sold under the sawasorb shadow brand.

Recently Sandler developed a new Sawasorb article—Sawasorb exterior. “As the name suggests,” said Klaus Tröger, the company’s senior sales manager, “it will be mainly applied in the outer area of the car. Sawasorb exterior passes the high level targets for outer absorber materials regarding very low water absorption and quick dehumidifying. Sawasorb exterior works without any foil and is mostly placed together with outer wheelhouse liners. Optimal acoustical features combined with high mechanical figures make Sawasorb exterior an ideal material,” he said.

Another European supplier to the automotive industry is Colbond, Arnhem, The Netherlands, which supplies Colback as backing material for molded car carpets and option mats and as support medium for cabin air filters. In addition, the material’s properties offer an advantage in various other interior products, such as hood liners, trunk liners, door panels, package trays and car seats.

As a premium product, Colback is used in executive class cars, where quality and performance are of prime importance as well as in mid and lower end cars where its high performance can reduce total costs of the end product. The range of Colbond products for the automotive industry also comprises three-dimensional spacer material (Enka-Spacer) used prior to PUR foam injection or other RTM processes to hold the reinforcement layers applied in place and ExSpray, a spray absorbing matting used at the inside of mud flaps of trucks and buses.

In the U.S., Lydall, which is headquartered in Manchester, CT, has unveiled DbCore (gradient density) and PolyTack ZeroClearance. Gradient Density DbCore is a lightweight, recyclable acoustical barrier with enhanced noise abatement characteristics capable of tuning out specifically targeted noises. The product is currently employed as a dash insulator on a number of pick-up truck models. PolyTack ZeroClearance is an extension of its ZeroClearance product line that includes shields that adhere via a unique, high-temperature, pressure-sensitive adhesive to a variety of hot spots on the underbody of vehicles. The PolyTack shield is specifically designed to adhere to and insulate plastic (HDPE) components such as plastic gas tanks.


R Is For Replacement

As nonwovens continue to meet tougher technical requirements, their role as a replacement for traditional materials has expanded. Finer denier fabrics are now being used so that trim, such as seat backs and package trays, are more cloth-like than carpet-like. Malivlies is having its first application (as a Cobalt package tray) to address the same issue.

Freudenberg’s Lutradur spunbond polyester nonwovens are used as primary and secondary backings for molded automotive carpets

Evolon facings from Freudenberg offer advanced design options for car interior applications

Freudenberg’s Evolon monolayer facings are also used as pillar covers, requiring no adhesive or barrier and featuring light weights (50% reduction), high production readiness and in-mold-cutting.
Freudenberg Nonwovens is a leading player paying close attention to the trend toward more cloth-like fabrics. The company’s latest products incorporate prints that give the nonwoven a woven pattern appearance. Freudenberg has also noticed interest in products that are softer to the touch. Also interesting are headliner products printed with multiple pigments (e.g. blue and gray) that complement different interior color configurations, allowing the OEM to use a single headliner for all vehicles within one platform. “We have also explored nonwoven products that have superior cleanability properties versus traditional textiles,” said Walter Schwarz, president & CEO, Freudenberg Nonwovens North America. “In addition to headliner applications, we offer our Evolon materials in various sound attenuation applications. In cabin air filters, we continue to evolve filters that will remove odors from diesel engines and other odor sources.”

In addition to mimicking wovens, another successful approach for nonwovens suppliers has been responding to auto market needs with a variety of flexible products. This is the case at eswegee Vliesstoff GmbH, Hof, Germany, which is a partner to both OEMs and Tier-1 suppliers. “Our range of technologies—from needled, binder bonded, thermally bonded, Malivlies, Maliwatt, Kunit and Multiknit—allows us to offer material solutions for almost every application as far as nonwovens are concerned,” said Detlev Käppel, eswegee’s global sales director.

For its part, Sandler’s new developments cover a full range of interior applications including a passive in-seat air-conditioning system, custom-made products for fuel and oil filtration and air conditioning in the interior and engine and protective transport hoods for cars, trains and boats. This environmentally friendly packaging solution is designed to protect the vehicle and be easy to use.

Flexibility is not only important when it comes to product offerings, according to Freudenberg, it is also a key strategy in terms of supplier capability and interaction with customers. “The OEMs are turning to Freudenberg to manage design activity, rather than creating the design themselves,“ explained Mr. Schwarz. “We have stepped up to this challenge by increasing our design capabilities. In our carpet backing market, we have intense interface with customers on carpet design very early in the new vehicle design process. This requires continuous interface during the 24-36 month design cycle for a new car model. We have always been committed to intense customer focus and this has helped define our market position,“ he said.

Sandler is another nonwovens producer integrating its efforts directly into the product development of the OEMs. “The reasons are obvious,” Mr. Tröger explained. “Systematic producer-specific material developments permit integration into new concepts at an early stage. Companies that accept and quickly realize these signals will perceive the positive effects in the mid-term. This will be connected with much more intensive and extensive development work than was the case previously.”


Competition & Costs

In the face of steeply rising costs, companies are facing stiff competition from fellow suppliers as well as from new entrants into the automotive market. Mr. Käppel of eswegee described the market as an environment where competitors are fighting for orders and battling increasing raw material prices. “Even companies who have not been in the automotive business before are trying to enter the market because of decreasing demand for their other segments.” Mr. Käppel added that Hof is working on several new products and plans to further improve its competitiveness and products through capital investments. Details on these plans have not yet been released, he said.

From the point of view of Gajanan Bhat, associate director of TANDEC and a professor at the University of Tennessee, Knoxville, TN, the bottom line is that suppliers have to convince car makers that new products are as good or better than the products being used. “This is true with respect to properties, performance, appearance, processability and cost competitiveness,” he offered.

In addition to heightened costs, a key challenge for Freudenberg is the increasing volatility of vehicle builds for each platform on a month-to-month basis. “This requires greater management of our production schedule to optimize utilization,” said Mr. Schwarz. “We have also struggled with the large run-up in raw material costs resulting from the rise in oil prices. The entire automotive supply chain has struggled with these cost increases and in some cases this has contributed to the bankruptcy of some major suppliers.”

Mr. Käppel of eswegee also pointed to certain U.S. and European companies that have recently filed for Chapter 11 as evidence of the difficulty suppliers face in handling soaring raw material costs. “OEMs and Tier-1 suppliers must address this problem and deal with it in a proper way. Otherwise there will definitely be an adjustment concerning the number of suppliers and sub-suppliers to the OEMs,” he opined.

“Raw material costs and supplies are the biggest hindrance in the supply chain to satisfy these market requirements of quality and cost,” agreed PCC’s Mr. Kamat.  “We have seen a steady increase in raw material costs, especially after Hurricane Katrina.”  

Something Natural?

Although efforts toward recyclability continue in the automotive sector, neither heightened consumer awareness nor environmental regulations are putting enough pressure on marketers to push for more environmentally friendly nonwoven materials. As TANDEC’s Dr. Bhat suggested, while there is continuing interest in natural fiber nonwovens and composites, as well as biodegradability, ultimately it is important that other desired properties are achieved. “As more research is being done,” he said, “other benefits of natural fibers, such as low cost and better thermal and acoustical insulation properties, are realized.”

Freudenberg’s Mr. Schwarz echoed this view. “We see some OEMs value a product that improves recycling capability, but this varies by customers and is not currently driven by regulations,” stated Freudenberg’s Mr. Schwarz. As an example, a 100% PET component has a value to certain customers due to improved recycleability versus a part that incorporates multiple polymers. This situation is the same in the company’s carpet backing business, where the focus is more on lighter weights for fuel economy than recyclability. “Our carpet backings do have recycled content, but this added feature is not a principal focus of our automotive customers,” he said.

A key environmental decision on the table today, according to Dr. Chen of LSU, is fiber material selection. “In the use of eco-friendly fiber materials, there are two directions: use of natural fibers or use of a single polymer. The use of natural fibers is consistent with the development of biobased products promoted by the National Energy Policy. The use of single polymer is focusing on increasing auto interior parts’ recyclability at ELV (end-of-life vehicles).” Dr. Chen added that an example of this is an €2 million research project called CONCLORE led by University of Bremen in Germany. “The goal of this project is to bring all manufacturers—from polymer producer to auto maker—to a single table to develop single-polymer auto interiors enabling recyclability at ELV.”

Going Global

Partially because of the vast worldwide manufacturing base of Tier-1 and Tier-2 suppliers, globalization is impacting the automotive sector even more significantly than most other nonwovens segments at all levels. “There is more research and development work being done in different parts of the world” commented Dr. Bhat of TANDEC, “and results can therefore be implemented much more quickly.”

For Freudenberg, integration is a key strategy in meeting the challenges of an increasingly global marketplace. “To succeed in this business, a first or second tier supplier must have the resources to work with its customers’ sourcing, design and engineering management anywhere in the world,” explained Mr. Schwarz. “Ford may outsource engineering work to Mazda in Japan for a platform that is to be manufactured in North American and Europe. Without an integrated global team, it is not possible to be successful.  Freudenberg has always demonstrated our global capability and this has provided dividends in growing our global share position in the automotive industry,” he said.

Another company finding its global presence to be a major advantage is eswegee. “From our plants in Germany and the U.S., we are able to supply two-thirds of the total world automotive market from domestic production,” confirmed the company’s Mr. Käppel. “Further plans for Asia are currently under consideration. Sales offices in Hong Kong and Shanghai are alreday implemented to serve the OEMs and Tier-1 suppliers domestically,” he said.