Epicuticle- thin outer membrane covering the cuticle
Cuticle- protective layer of overlapping flattened cells called scales
Cortex- major component of wool fiber, inner layer
Medulla- the central core found primarily in medium and coarse wool
Caused by the unique chemical and physical properties of wool. The fiber tends to bend and turn in to a resilient 3 dimensional structure. It holds in air to insulate the wearer. This property make wool naturally elastic and resilient causing rapid wrinkle recovery, durability, bulk, loft, warmth, and resistance to abrasion.
Wool can absorb up to 30% of its weight in moisture without feeling damp or clammy. This makes wool good for all climates since it aids in the body's cooling mechanisms to keep moisture away from the skin.
Resistance to Fire
Wool contains moisture in every fiber allowing it to resist flame without any additional chemical treatment. The wool will just char and self extinguish.
Wool absorbs many dyes deeply, uniformly, and directly without the use of chemicals. This characteristic allows wool to achieve very beautiful and rich colors when dyed.
The flexibility of wool makes it very durable. A single wool fiber can be bent back on itself more the 20,000 times without breaking. Compare this to the only 3,000 times of cotton and 2,000 times of silk. Its elasticity makes it very resistant to tearing. Wool also has an outer film making it resistant to abrasion.
Wool fiber can be stretched up to 50% of its length when dry and up to 30% of its length when wet without breaking It will return to its original length when released.