Table (1)

Fuzz formation tendency of different fibers

However, viscose with low tenacity has a higher tendency to fuzz compared to Dacron that is 50% stronger. Thus, why cannot explain the magnitude of fuzz formation simply with reference to the tenacity of fibers ⁽¹⁵⁾. There are other factors involved.

Also, they reported the low inter-fiber friction as well as fiber stiffness in terms of fiber modulus facilitates migration of fibers out of fabric surface. Wool- has the lowest inter- fiber friction and moderate stiffness; its low tenacity causes the fuzz formation. As results of surface friction, several fibers are fractured and are able to easily migrate out of the fabric and get entangled in the pill.

Research work carried out by Richards ⁽¹¹⁾, Sharma ⁽¹³⁾ clearly indicate that as yarn becomes finer, pilling increased when all other yarn and fabric parameters were kept constant. There is complete agreement that increasing the twist factor of yarn decreases the pilling tendency as fibers find it difficult to easily migrate out. Several workers have confirmed that the higher yarns twist whether in singles or in double yarns the lesser is the pilling. ^{(8, 12, 14)}

Work carried out by kullman and Rupenicker ⁽¹²⁾ indicate that fabric woven from worsted spun yarns pill less than those from cotton spun yarns. Viscose gives more pilling than wool does when blended with polyester.

Sivakumar and Pillay ⁽¹⁵⁾ investigated the structure of pills and nature of fibers that go into pill in different types of fabrics were examined microscopically and the influence of fiber and yarn parameters was analyzed.

Kulkarni ⁽¹⁰⁾ suggested the use of higher cover factors for weaves other than plain weave structure to decrease the pilling tendency. He determined that warp and weft English cover factors from 12 to 14 are adequate for plain structure, and for twill and dobby structures he suggested cover factors from 15 to 18.

Wemyss ⁽¹⁶⁾ observed that finishing processes playa very important role than various factors responsible for pilling resistance. Poor finishing leads to pilling even in a well design fabrics. The main role of finishing is to stabilize the fibers inside the yarn and to remove the surface nap. This is done by heat setting, singeing and brushing I cropping.

2- Experimental work:

Polyester and wool are spun into yarn in three different blend ratio and yarn count on worsted spinning system with constant twist factor for single yarn (85) as well as for ply yarn (120), and woven into fabric using all the yarn samples as a warp and weft in three weave structure. The effect of heat set treatment at two different temperatures of 160 and 180 CO 5 Co, and singeing on both sides of fabrics at two speed level 40 and 60 mlmin are described. Experimental parameter and results obtained are given in table (2).

The fabric samples were exposed to standard atmosphere for 24 hours at least with relative humidity of 65 % 2 % and temperature 20 Co 2 Co. Pilling test of fabric samples was carried out on lCI pill box tester. The number of pills generated were counted in each samples and expressed as number of pills per square inch.