Nonwovens - since 2002, these diverse textile fabrics have seen something of a stratospheric rise with six percent annual growth in terms of its utilization for geotextiles. According to expert reports from the organization ‘Bayern Innovativ’, the construction sector was conversely the second-largest purchaser of nonwovens in 2010 with 18.2 percent of the overall market – just behind the cleaning cloth market. This cross-fertilization with the development of innovative products and the opening of new applications for the construction industry will ensure even wider utilization and greater demand over the coming years.

Important driving forces behind this trend are the increasing orientation of the construction industry on topics such as heat preservation, energy consumption and (sound) insulation including the corresponding legal guidelines. Even in thin layers, polyester nonwovens, for example, protect – as in the case of functional textiles – against overcooling and absorb very little moisture. For example, they easily adapt to roof constructions and are quick and easy to use as insulating materials and to replace render or cover cracks in fa?ade systems and can also benefit impact insulation. In both refurbishments and new-builds, they are therefore an excellent alternative to foams, glass and mineral wool, particularly in view of the fact that these materials frequently lack the required flexibility for optimum sealing. Not least, nonwovens are resistant to environmental influences and can be recycled to a high extent.

Flexible textiles have a very promising future – and are also entering the high-tech sector. To this end, we already have smart nonwovens, which integrate conductors or conducting materials. In the case of “intelligent floors”, they can automatically – by means of sensors – activate lights and are able to register the fact that a senior citizen has fallen over in a retirement home.

Roofing: trend towards spunbonds

In terms of industrial nonwoven applications, so-called roofing currently has the lion’s share of the global market with in excess of 420,000 tons per year. On the one hand, this application focuses on calandered polypropylene spunbonds, which are laminated with a breathable PP film and inserted between roof tiles and the load-bearing wood construction. In addition to these roofing underlayment membranes, bitumen roofing as a cover layer is predominantly used for flat roofs. The material comprises needle punched and heat-set PET spunbond that has been treated with an acrylic binder.

These nonwoven applications excel as a result of a series of functional properties: they provide a moisture barrier, but are nonetheless air-permeable and resistant to mold and mildew as well as being stable in terms of their dimensions and temperature; they can be installed easily onsite and be glued or welded together; they are resistant to fatigue, impact and penetration as well as resilient to debonding and work well with standard paints and lacquers.

With systems and equipment for manufacturing substrates for bitumen roofing membranes, for roofing underlayment and also for geotextiles, Oerlikon Neumag, one of the leading suppliers of nonwoven technologies, offers the complete spunbond process – from polymer granulate all the way through to rolled goods. “The combination of effectiveness, productivity and nonwoven product is particularly innovative in the case of the spunbond process. “Our plants not only have a significantly higher throughput by a comparable working width, they also help save operating costs for energy and maintenance as well as for operating personnel” explained Dr Ingo Mahlmann. The Oerlikon Neumag nonwovens expert sees growing opportunities for spunbonds within the construction sector, also because they are particularly inexpensive to manufacture: “The trend is very clearly moving towards utilizing spunbonds, also as a substitute for fiberglass products. Bitumen roofing and geotextiles are perfect examples of this, but this trend fundamentally also applies to many other construction nonwovens, such as those used for reinforcement or drainage.”