I think they are just called wool fibres. Look at the related link below:
A natural fibre which comes from the hair on a sheep
it is made by your mum
Natural. Synthetic material comes from material that is man-made, usually from petrol-based materials.
Wool, on it's own is itchy so it is mixed with other fibres to make it more comfortable to wear.
Lamborghini Sesto Elemento Concept Car Review
How to Insulate Your Home
Learn about First Aid, Fibre and Baby Feeding
The Lamborghini Sesto Elemento