Page 22 - Shawl Weaving Artisan - TT

4 Moisture absorption: Wool fibers can absorb 2 This layer is made of flat, irregular horny scales with
moisture, making them breathable and comfortable. projecting edges that are pointing toward the fiber tip.
Wool can absorb up to 30% of its weight in moisture 3 Cuticle acts as the protection to the main parts of fiber.
without feeling wet.
4 This layer gives the rigidity to the wool fibers.
5 Thermal insulation: Wool fibers provide good
thermal insulation, keeping you warm in cold 5 Cell width – 36 microns
temperatures and cool in warm temperatures. This 6 Thickness – 0.5-1.0 microns.
is due to the natural crimp of wool fibers, which traps
air and provides insulation. 7 Visible length – 16 microns.
6 Color: Wool fibers can be dyed to a wide range of 8 With an increase in diameter, the number of scales
colors. Wool dyes well because of its protein structure, also increases.
which allows it to bind with dye molecules. Cortex
Chemical properties of wool 1 This layer forms the body of the fiber.

1 Protein composition: Wool fibers are made up 2 This layer contains long, slightly flattened and twisted
of keratin, a protein that gives them their unique spindle-shaped cells.
properties. Keratin is a complex protein consisting of
amino acids like cystine, serine, and glycine. 3 The cell length is 80 – 110 microns.
2 Acid sensitivity: Wool fibers are sensitive to strong 4 This layer is responsible for strength, elasticity, and
acids, which can damage or disintegrate them. Weak dyeing behaviour.
acids, however, can be used to dye or finish wool Medulla
fibers.
1 This is the central core which runs lengthwise through
3 Alkali sensitivity: Wool fibers can be damaged by the fiber.
strong alkalis, which can break down the keratin
protein. Mild alkalis can be used for some finishing 2 This layer occupies a 10 – 80% volume in fiber.
treatments, but strong alkalis should be avoided. Detailed structures are shown in the Fig 5 below:

4 Dyeability: Wool fibers can be dyed using a variety Fig 5
of methods, including acid dyes and reactive dyes.
The protein structure of wool allows it to bind with dye
molecules, creating a wide range of colors.
5 Finishing treatments: Wool fibers can be treated
with various finishes, such as shrink-resist treatments,
to enhance their performance and durability. These
treatments can improve wool’s resistance to pilling,
felting, or shrinkage.
6 Chemical reactivity: Wool fibers can react with
certain chemicals, such as oxidizing agents or
reducing agents. These reactions can affect the
properties of wool fibers, so care must be taken when
using chemical treatments. Woollen and worsted yarn (Fig 6)

Overall, wool’s unique combination of physical and 1 Woollen yarn
chemical properties makes it a popular choice for
clothing and textiles. Its natural crimp, elasticity, and Woollen yarn is thick and usually created from the shorter
moisture absorption properties make it comfortable fibers of the sheep’s fleece. Woollen yarn is soft, light,
and breathable, while its protein structure and chemical stretchy, and full of air. The fibers in the woollen yarn are
reactivity require careful consideration when dyeing or held loosely and subjected to only to only a limited or less
finishing wool fibers twist during These yarns are woven into thick bulkier
materials are ideal for warm winter jackets, sweaters,
General structure of wool skirts, blankets etc. Woollen yarn is used to make thick,
Technically wool contains three layers. heavyweight woven or knitted garments. The maximum
length of woollen yarn that can be spun from one pound
1 Cuticle
is 54 hanks each of 256 yards.
2 Cortex
2 Worsted yarn
3 Medulla Worsted is a high-quality type of wool yarn, the fabric
Cuticle made from this yarn. Worsted yarn was made from
the long-staple pasture wool from sheep breeds such
1 This is the outermost layer of the wool fiber.

12 Textile & Handloom: Shawl Weaving Artisan : (NSQF - 2024) R.T. Ex.No 1.1.05