The definitions vary
The nonwovens industry is colorful and heterogeneous. Opinions differ greatly on how exactly to describe what "Smart Nonwovens" actually are and how they can be differentiated from other nonwovens. Even the precise definition of them as an "intelligent material" is still not quite accurate enough. For many people the nonwoven product simply has to perform a "smart" or clever task – without it necessarily having to forcibly undergo a change of any kind as the result of external influences.
Geotextiles – quite simply intelligent
A very simple example of a Smart Nonwoven is a needled geotextile, as used in highway or waterway construction. It prevents different materials such as sand and pebbles from getting mixed together. This makes the construction job cheaper, more stable and more durable. The water flow and the good filtration properties of the material are supported by the mechanical properties of the geotextile. This guarantees that water can flow through without a problem, but not fine particles – a clever solution!
There are other geotextiles that change their properties as a result of environmental influences. These geotextiles are structured in several layers and needled together. A material is integrated into the intermediate layer which expands on contact with moisture. The geotextile thus becomes water-impermeable. These special geotextiles are used for applications such as soil-covers during the construction of garbage dumps. They prevent the soil and the groundwater from becoming contaminated.
Nonwovens that think along with us – economic benefits
Smart Nonwovens also contain nonwoven products that "think along", however. These change their properties or transmit information via integrated electronics. Here, electronics is turning conventional nonwoven products into smart and intelligent end products.
One example is the attachment of conducting paths to nonwovens to test the body's vital functions. Nonwovens with very high-quality surfaces are the most suitable for this purpose. In comparison to woven or knitted textiles, their surface is especially uniform and even. The uneven surface of woven and knitted materials often requires integration of a conducting path into the product in the form of a metallic thread. The printing-on of the conducting paths that is possible in the case of nonwovens is normally far less expensive than having to work them into a textile, however. No wonder, therefore, that nonwovens are often the first choice!
The precise production methods for these innovative nonwoven products are exceptionally complex, and vary from one manufacturer to the next. One very frequent production method is hydroentanglement. A special challenge where printing of conducting paths is concerned is optimum application of the conducting ink to the nonwoven product. The ink has to penetrate the fabric far enough not to be washed out after the first machine cycle, but it must not run either. The material properties of the ink and the nonwoven have to be very well coordinated.
Smart and tailormade – the Groz-Beckert portfolio
Smart end products are inconceivable without smart precision components. It has to be guaranteed that the conducting path, consisting of conductive ink, is not interrupted by overly uneven surfaces. The most stringent requirements have to be placed on surface uniformity! Poor-quality jetstrips or felting needles are no alternative here. The quality of the surface would be endangered because of the lack of precision.
Good that Groz-Beckert is around. The company's broad portfolio of products for the nonwovens industry always offers suitable solutions in every case, all of them distinctive for the highest quality and process reliability:
In the case of hydroentangled nonwoven products, the jetstrip plays a crucial role where surface quality is concerned. Alongside the HyTec® Boothard jetstrip, Groz-Beckert also offers two especially innovative models: HyTec® GEBEDUR® – with special coating for long service life while retaining the highest quality – and the newly-developed HyTec® D. With regard to hardness and resilience, the new jetstrips have been optimally adapted for use in spunlace machines.
Increasingly, however, waterjet-hydroentangled products are having to be needled first before the entanglement process. In this case, two different precision components from Groz-Beckert come into play: not only jetstrips but also high-performance felting needles.
For the production of geotextiles, on the other hand, the felting needles Tri STAR® and Cross STAR® are ideal. With their concave working-part sides and more acutely angled edges, Tri STAR® needles are impressive for their improved fiber transport and enhanced grip of fibers in the barb. Cross STAR® needles are especially suitable for very thick geofelts, even where heavier materials are concerned.
Attractive & promising – Smart Nonwovens have potential
However "intelligent materials" and "Smart Nonwovens" are precisely defined, ultimately it's the results that count. A world-famous and appealing example of how geotextiles can aid artificial land reclamation is of course "The Palm, Jumeirah". The artificial island extends from the harbor of Jebel Ali to downtown Dubai, and has now established itself as a unique tourist attraction.
Nonwoven products that "think along" still have their future ahead of them. The amazing speed of development in microelectronics and the manufacture of new fibers and textile products will very soon ensure that Smart Nonwoven products are as normal as the electric car in the garage.
The Palm, Jumeirah, Dubai