Needle Felt: The Next-Generation Material for Occupant Safety Systems

BY ALT Technologies | 06th February 2022

In line with new and improved automotive safety standards and vehicle developments, needle felt leads the way as a vital material in airbag cover manufacturing.

Side Airbag
New felt cover may be used in the passenger or knee airbag, or side airbag inside the seat


Airbags are a crucial component in overall vehicle safety features. Although an airbag’s sole purpose is to keep car occupants safe, how are airbags themselves protected? After all, they are supposed to last the lifetime of the vehicle.

Airbags need a cover that can withstand harsh environments while also being fragile enough to allow the airbag to inflate in a fraction of a second. Through working with all the major car brands globally,

ALT has developed a new airbag cover made from needle felt that meets OEM’s stringent testing requirements.

In this article, we will outline how we created this enhanced airbag cover and its many features and benefits.

Today’s Vehicles Require Lightweight Solutions

Fifteen years is a long time for materials to waste away or become weakened by vibrations and other vehicle movements.

If the airbag inflates, that explosion must be contained to protect the car occupants.

On top of these, the cover also needs to guide the airbag in the right direction so it does not tear or malfunction.

airbags in new Mercedes
Airbags deployed in a modern Mercedes-Benz car in a safety demonstration at the IAA Mobility 2021 motor show in Munich, Germany – September 6, 2021


An airbag cover clearly needs to meet a lot of functionality requirements.

How do we also ensure we are meeting updated automotive features?

Having previously worked with PP non-wovens to create a metal bucket and plastic top airbag cover, this proved to be too heavy to continue developing.

We are now investing in needle felt material to craft sleeker covers due to the demand to keep electric and autonomous vehicles as lightweight as possible, while also retaining their shape and function for the vehicle lifetime.

How We Keep Car Occupants Safe

After rigorous trialling using our ovens, moulding and die-cutting tools, we were able to begin moulding needle felt into different structures. It is lightweight, malleable and easy to work with.

Needle felt is made from PES (polyethersulfone), this is a PET-based material with bico fibres. The 2D or 3D moulded felt comes as a raw material with varying thicknesses on a roll that looks like a carpet.

Felt airbag cover
Specified moulding into the desired shape

The Process

1) The fabric is heated up in a convex oven at a specific temperature and compressed in the mould under a load.

2) The PES material, together with the bico elements, melts together homogeneously and then becomes a specific density under pressure.

3) We use this procedure to make 2D and 3D shapes depending on which moulds we need.

4) When the needle felt is dried, it is taken out of the mould and cut and bent into the required form.

5) The cutting machine creates perforated tear lines and creates a hinge (like a clam) which enables it to shut around the airbag and inflator.


Redesigning Airbag Covers for The Future

Our needle felt airbag covers could reduce the weight of typical covers and airbag housing by up to 90%! Old covers were too rugged to position in car seats and protruded at awkward angles.

We can simply weld or stitch the cover closed and then put foam or leather fabric over the airbag cover within the seat. This cover easily follows the seat’s contours without protruding through the surface as it is far more pliable.

Stitched felt airbag cover
Stitched felt airbag cover


The key features of needle felt airbag covers are:

    • Compactness: they require minimum space.
    • Low weight: when the materials are melted and moulded, they are a lot less dense than previous plastic or metal covers.
    • Temperature resistance: they can withstand high-temperature inflation gases under short-term exposure.
    • Cost-effective: compared to the current airbag cover solution, it is less expensive or else costs around the same.
    • High quality: they are made from bico fibres that provide high strength, hardness and good chemical resistance. They have excellent sliding properties and good electrical insulation properties.
    • Durability: the PET-derived needle felt is highly durable in a compacted state over many years.
    • Chemical resistance: needle felt has high resistance to abrasion and low absorption of humidity.
Needle felt airbag covers: the finished product
Needle felt airbag covers: the finished product

A Solid Structure for Future Cost Savings

Our core engineering team continuously research and develop based on our customer’s needs to ensure they are always ahead of the demands, such as catering to new lightweight vehicle components.

As well as airbag covers, we also provide automotive labels (including RFID), protective components, printed electronics and inflator seals. ALT offers comprehensive solutions that continuously add value, so you do not need to scramble for profitable materials. Why not check out our airbag cover solutions, as well as all our other automotive products.

Get in touch with our expert team for more information today.





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