Bayer MaterialScience offers a diverse product range for DirectCoating technology
A customized, harmonious interior design is an important factor for an increasing number of car buyers. Surfaces should exude quality, feel good and be robust enough to withstand everyday wear and tear. At the same time, the automotive industry is committed to reducing the cost of manufacturing components and significantly improving productivity. The DirectCoating/DirectSkinning technology co-developed by Bayer MaterialScience fulfills all of these requirements. Combined with special plastic grades, the process allows coated components to be manufactured efficiently in a single step.
The surfaces of various components can be freely designed over a broad range to meet individual customer demands. “Transparent or colored coatings based on Bayer raw materials have been formulated in such a way that their appearance can vary from matte to glossy to a piano-like finish,” says Dr. Johannes Scherer, project manager of the DirectCoating/DirectSkinning. “The feel can be set to hard or soft. Pebbled and structured surfaces are also possible with the appropriate mold design.” This development is part of a new, integrated material concept from Bayer MaterialScience for the future of automotive interior design.
Production in a single mold
In the DirectCoating process, a plastic substrate is injection molded in the first cavity of a two-component mold. When it is then placed in the second cavity of the mold, a narrow gap results that is flooded with a polyurethane coating as the second component. “After opening the mold, the ready-coated part can be removed immediately for further processing,” explains processing engineering expert Jan Helmig. “The surface structure of the mold has been transferred perfectly to the polyurethane.”
Optimized substrate materials
Bayer MaterialScience provides various materials made from its Bayblend® and Makroblend® lines of PC blends. These all possess outstanding heat resistance and impact strength. Specially developed for this process, the products are also characterized by excellent adhesion to polyurethane systems that also stands up to weathering.
The new Bayblend® grades for car interiors, for example, exhibit significantly improved coating adhesion compared to standard blends. Materials in the Makroblend® series demonstrate impressive low-temperature, weather and media resistance, making them ideal for exterior use. Good coating adhesion is particularly crucial for car exteriors when the vehicle is exposed to a variety of weather conditions, including UV radiation.
The concept developed by Bayer MaterialScience provides customers and end users with a matched system that fulfills the desire for high-quality materials with decorative and robust surfaces. These products are already available for customer projects.
Versatile look and feel
While it is the substrate materials that ensure the components are lightweight and robust, the decorative look and pleasant feel come from the coating. Bayer MaterialScience’s partners offer various, solvent-free coating systems for the DirectCoating process. They are based on raw materials from the Desmodur® and Desmophen® lines, and are characterized by excellent resistance to weathering, chemicals and scratching. Self-healing systems can also be used.
Depending on requirements, transparent and colored coatings are available that provide high-gloss, matte or structured surfaces as desired. Haptic coatings for the interior are also available in various degrees of softness. One example is a Bayflex® polyurethane system that gives a compartment in a production sedan the look and feel of natural leather using the DirectSkinning process.
