Needle-punched fabrics

Principle appHcations of needle-punched nonwovens for the 1990s include automotive, apparel components, blankets, carpeting, carpet pa dding, coating substrates, filtration, furniture, geotextiles, insulation, roofing substrates, and wall coverings. In 1990, the production of needle-punched fabric was estimated to approach 91,000 t and 606 million square meters (15). 

Geotextiles. Nonwoven fabrics have played an important part in the development of geotextile appHcations. Both needle-punch fabrics... 

High Pile and Needle Punch Fabric Bonding... 

The activated carbon granules were coated in substrates (e.g., polyurethane foam and non-woven pads) for use as an interliner in the clothing system however, the coated polyurethane foam usually has low air and water vapour permeabihty, and it is reported that needle-punched fabrics coated with activated carbon have better thermal comfort properties. The coated activated carbon material is combined with other textile materials in permeable CPC to provide two main functions ... 

Non-woven fabrics are formed directly from short fibers that are assembled in sheets. The fibers are connected together to enhance the handlability of such sheet of otherwise loose fibers. Rows of needles are sometimes used to punch through the sheet of fibers and reorient some of the fibers to achieve mechanical adhesion between the fibers (needle punched fabrics). This process, although very successful with polymer fibers such as para-aramids, has less success with brittle ceramic fibers such as glass and carbon because fibers can easily break. Another method used to connect the short fibers is by using an adhesive to glue the short fibers to one another. In the case of short fiber composites, this glue will typically have a chemical affinity to the resins. 

Table 10.6 Uses of felted needle-punched fabrics...

This market received a boost in the early 1990s when the EPA issued the first federal standards for municipal solid waste landfills. The main objective was to prevent leakage and protect groundwater and soil near the landfills. Needle-punched fabrics are used as a geotextile cushion specifically where there is need for puncture protection, often on top of the liner, and as blankets in drainage systems inside the landfill, as a tarpaulin on the outside of the landfill, and underneath as a foundation for erosion control. 

Nonwoven fabrics have played an important part in the development of geotextile applications. Needle-punch fabrics manufactured from either staple fibers or spunbonded continuous filaments have found worldwide acceptance on the basis of field performance. In 2000, it is estimated that North America consumed approximately 300 million m of geotextiles (62). 

Needle-punched nonwoven fabrics are made from various fibrous webs (usually carded webs) in which hbres are bonded together mechanically through fibre entanglement and frictions after hne needle barbs repeatedly penetrated through the fibrous web. Needle-punched fabrics have characteristic periodicities in their structural architecture that result from the interaction of fibres with the needle barbs. Fibre segments are reorientated and migrated from the surface of the web towards the interior of the fabric, forming pillars of hbre orientated approximately perpendicular to the plane. 

Bell et al., 1977). This work culminated in the first US Federal Highway Administration design and construction guidelines (Steward et al., 1977 Bell et al., 1975 Mohney, 1977 Steward et al., 1977 Bell and Steward, 1977). An altogether different application was developed in 1966 by Phillips Petroleum Co. using field bitumen-saturated nonwoven needle-punched fabrics to control reflective cracking in asphalt pavement overlays (Dykes, 1985). 

---