Effect of Fiber Properties on Yarn Hairiness in Ring Spun Yarn

Effect of Fiber Properties on Yarn Hairiness in Ring Spun Yarn

Effect of the Type of Fibers and Their Properties on Yarn Hairiness on Ring Spun Yarn

S.Sivakumar 
Production Manager 
Oxford Amalgated PLC, Ethiopia 
Email: skumars72ss@gmail.com

Yarn Hairiness: 
Yarn hairiness is the amount of fibers protruding from the yarn body measured in terms of its length and number of fibers. Now a days hairiness plays a vital role in accessing the yarn quality as it heavily influences the quality of the fabric produced from the spun yarn in knitting as well as weaving. The essential fabric properties of pilling resistance and abrasion resistance are affected by the yarn hairiness. Also the performance of Warping machine, Sizing machine, high speed knitting and high speed weaving machines are also affected by the yarn hairiness.

Yarn hairiness

Measure of Hairiness : 
Hairiness is measured in two methods. 

A. Hairiness Index (H): USTER introduced this method of testing. It is the value represents the total length in CMs of the protruding fibers in 1 CM length of yarn. 

B. Hairiness Index (S3): ZWEIGLE counts the number of protruding fibers of different lengths separately. S3 value is the sum of the number of fibers of 3 mm and longer length of protruding fibers. 

Hairiness is widely influenced by fiber properties, process parameters, spindle speed, traveller selection, machinery conditions, Relative humidity and amount of twist. But in this article we are discussing about the fiber properties. They are,

1. Torsional rigidity
2. Fiber length
3. Fiber fineness
4. Short fiber content
5. Uniformity
6. Fiber cross section / shape

1. Torsional Rigidity 
It is the ratio of the torque applied about the central axis of the yarn at one end of the yarn to the resulting torsional angle, when the other end is held fixed. On other hand, it is the resistance of the textile fiber or yarn against twisting. The torsional rigidity of the cotton fibers are very much depends on their fiber fineness. It is very sensitive to the Relative humidity. 

This is the prime property which affects the hairiness of yarn. The fibers with higher Torsional rigidity have higher yarn hairiness and vice versa. 

2. Fiber length 
The yarn hairiness reduces with increase in fiber length. The reason is the reduction in number of fiber ends protruding from the yarn surface resulting in less hairiness. While using longer fibers, the fibers tend to overlap on the yarn surface in a better manner and hence improve the compactness of yarn which results less hairiness. 

3. Fiber fineness 
The yarn hairiness is less for finer fiber and higher for coarser fiber. The torsional rigidity is the most essential property of the fibers contributes to the formation of hairiness. Generally the finer fiber will have less torsional rigidity and hence the hairiness will be less. The coarser fiber has higher torsional rigidity and higher hairiness in yarn. When the yarn delivering to the front roller nip and while twist insertion, the higher centrifugal force acting upon the coarser fiber leads to higher hairiness. 

4. Short fiber content 
SFC has positive correlation with the yarn Hairiness. Increase in SFC will increase yarn hairiness and vice versa. The increase in number of protruding ends in yarn surface due to shorter fiber length leads to increase the yarn hairiness. 

5. Uniformity Ratio 
As the increase in Uniformity ratio improves the mean fiber length and hence this property having a negative correlation with yarn Hairiness. 

6. Fiber cross section / Shape 
Comparing the circular and non-circular cross sectional fibers, the yarn hairiness is less with the yarn spun with circular cross sectional fibers. The compactness of fibers while using circular cross section fibers is better than that of other and hence the hairiness is less with circular cross section fibers. 

But the impact of twist on hairiness in non- circular cross section fibers is better than circular cross section fibers. Higher the twist will reduce the Hairiness to more extent in non- circular cross sectional fibers. 

References

1. Influence of fiber length and denier on properties of polyester ring and air jet spun yarns. – A Basu& K P Chellamani – IJFTR – Vol.25-Sep 2000
2. Influence of Polyester fiber shape and size on the hairiness and some mechanical properties of yarns. – R K Vashney, V K Kothari & S Dhanija – IJFTR – Vol.39 –Mar 2014
3. The Use of Monte Carlo Techniques to study yarn hairiness for Ring spun yarns. – RMUTP International conference- Textiles & Fashion 2012 – July 2012
4. Torsional properties of staple fibre plied yarns – D G Phillips, W B Fraser and G H M Van der Heijden – Nov 2008
5. The Rieter Manual of spinning – Vol.1 – Technology of short staple spinning – Werner Klein