According to the same source, the dissemination of nonwovens on product group shows that insulations represent 17% (sqm) from the total applications. Others applications are: carpet related products (43%), trunk (13%), hood liner (10%), seat (6%), headliner (6%), rear shelf (3%), door (1%), others (1%).

Within a car the acoustic materials can be used in structures such as: door panels, headliners, A-B-C pillars, luggage compartment, under bonnet/hood liner, floor carpet underlay mat. According to the specific destinations, automotive nonwovens insulations can have different appearance and can be separated into three categories:

1)      Composite /laminates used as replacement of PUR

2)      Pressed /molded interior components from renewable raw materials.

3)      Bulky, wadding, acoustical parts.

Nonwovens used as replacement of PUR:

Textile composite used in cars refers to combination of one or more textile and/or non-textile materials, e.g. foam and warp knitted fabrics used as upholstery or interior trim materials. However, three-dimensional nonwovens are lately considered as replacement for PUR foam. Some of the advantages of such "textile foam" are:

• reduced fogging and unwanted odors
• environmental-friendly laminating process
• surface material uniformity
• possibility of using reclaimed fibers
• recycling into reclaimed or recycled fibers

 

Some technologies to process bulky, compression-elastic nonwovens are:

• carding and vertical lapping: e.g. STRUTO, WA VEMAKER
• Stichbonding processes: KUNIT, MULTlKNlT, MALlVLlES; e.g. Caliweb is a trademark of products manufactured by use of Kalitherm technique. It refers to mechanical (Kunit and/or Multiknit), thermal bonded and calibrated nonwovens as well as for 'the composite lamination of such nonwovens with any surface fabric.
• 3D Weblinker, NAPCO technology for 3D structures

 

3.2. Pressed components from materials molded interior renewable raw materials:

 

After having been almost completely replaced by their synthetic counterparts in 60's and 70's, natural materials are gaining ground in automotive applications as moulded fiber part components: interior trim parts/door panels, roof linings, luggage compartment linings, parcel selves.

 

Fibers with high strength and low elongation properties are required for composites, and most of the bast fibers fulfil these requirements. With a good availability and a comparatively low price, flax, sisal, jute and coconut play the most important role. Though hemp provides stronger fibers than flax, as the processing of hemp fiber is not yet sufficiently sophisticated, flax remains the commercially most important plant fiber. Some comparisons between flax and other reinforcing fibers can be seen in table 3.