Fibre Diameter

It is clear from the price paid at auction that this property is the most important considered by both suppliers and processors of wool. Its importance is largely due to its contribution to softness and to the fact that the finer the fibre finer yarns can be generated.

This is critical to Australian Merino wool in the modern apparel industry as demand by the modern consumer is driving luxurious comfort and enjoyment in wear. This can be see in the increase of light weight wool fabrics moving into the sports performance and next to skin markets.

Over the last 10 years the average fibre diameter and the distribution of fibre diameter in the Australian clip has trended towards the finer with  83% of the clip less than 24 µm, and 35% less than 20µm.

Finer wools tend to be more difficult and more costly to process and it is therefore important to know and understand the optimum way in to mechanically process.

Staple Strength

Staple strength is very important in contributing to the average fibre length and distribution of fibres in the top. If Australian Merino is blended (particularly with synthetic fibres) then the role of staple strength in post top manufacture becomes less and less important. This is because once the weak place in the staple is broken, predominantly in carding and combing, then the remaining keratin in the individual fibres remains sufficiently strong to meet the downstream processing and product requirements.

In recent years, many suppliers and processors of wool have realised this and taken advantage of the relatively low price of low staple strength wools, particularly for use when blending with synthetic fibres.

Staple Length

Length is a poorly understood property by many of the processors of wool. It is clear that longer staple length gives longer top length and this in turn improves spinning performance and product performance particularly with reference to “fuzziness” of the surface and potential pilling of the end product.

Co-efficient of variation of diameter (CVD)

Co-efficiency of this property can be important in pure wool next to the skin application or in high wool content blends. It is important that suppliers and processors understand that in other applications such as outerwear the role of CVD is less important and selection of wools and the specifications for the CVD should be dependant more on the final end use of the wool.

 Fibre Crimp

With the development in recent times of niche marketing of wool this property has become of increasing importance. Recent work by Robinson and Haige has indicated that fibre crimp is particularly important in the looser more open structures of knitted products where it has a significant influence on determining movement of fibres and of yarns and fabrics in determining final fabric weights, shrinkage and pilling behaviour of knitwear. In the higher twisted, tighter set products in wovens fibre crimp plays a lesser role.

Nevertheless, as higher crimp fibres tend to move more during finishing operations, this fibre property contributes to the fabrics dimensional stability and final fabric geometry. The knowledge and understanding of the contribution of this fibre attribute is becoming more important.