Cotton Fibres – The King of Fibres

Cotton is the “King of Fibre” and the most used fibre in the world. It grows in a boll-like structure around the seeds of the cotton plant. Cotton fibres are defined as soft, cushy, fluffy and cool staple fibres or natural hollow fibres known as breathable fibre and absorbent. They are the most essential natural yarn fibre, as well as cellulosic textile fibre in nature which is used to produce attire, home furniture and other industrial products.

Also check out- Jute Fibres – The Fibre Of Future – My Biology Dictionary

Since ancient times cotton has been refined by humans mainly in Africa, India, South America and Central America. Currently, by predominating China, India become the world’s largest producer of cotton. India is the only country where all four types of species are grown. Major cotton-growing states are Gujarat, Punjab, Haryana, Andhra Pradesh, Karnataka, Tamil Nadu and many more. Recently, the largest producer of cotton in India has been Gujarat. Texas is the largest producer in the U.S.

COTTON FIBRES SPECIES:

To begin with, the word “cotton” is derived from the Arabic word ‘qutn’ or ‘qutun’. This plant belongs to the Gossypium genus and Malvaceae family. Different species of cotton are:

• Gossypium arboreum
• Gossypium herbaceum
• Gossypium hirsutum
• Gossypium barbodense

In this fibre, cellulose is found almost in its pure form and may contain some amount of water, fats, pectins, waxes, etc. Under ordinary situations, the cotton bolls will boost the dispersal of the seeds.

PHYTOMORPHOLOGY OF COTTON FIBRES:

The morphology of different species or types of cotton plants is as follows:

Gossypium arboreum:

It is a seasonal, annual or branched shrub. The length of the plant is 1.5 m to 2 m tall. Its blooming leaves and twigs are juvenile. Seeds are small and are various in numbers like 6 to 17 per loculus. Seeds have short hair or fuzz with the grown-up root system and are drought tolerant. Fruit is like a boll and pointed with extended oil glands. In India, this species of cotton is grown approximately 29%  of all the types of cotton grown in India.

 

Gossypium barbodense:

This species of cotton fibre are used in luxury fabrics. It is annual sub-shrubs and the length of the plant is 1 m to 3 m tall. In this species of cotton plant, leaves are exposed and densely packed with a long grey hair-like structure. Leaves are highly lobed and the size of the bolls are large, bold and round and contain 5 to 8 seeds per loculus. There are no hair-like structures on the seeds. Total of 8% contribution to cotton production.

 

Gossypium harbaceum:

It is a small tree or sub-shrub. The length of the plant is 1m to 1.5m tall.  The stem is thick and rigid, and the leaves are parallel arranged. Fruit or boll is round and contains 10-11 seeds per loculus with

3 to 4 lobules. Seeds have short hair-like structures fuzz and lint. Approximately 21% of the area this species of cotton is grown.

 

 

Gossypium hirsutum:

It is also known as “Upland cotton”. About 90% of the world’s production used this species of cotton. It is a small annual shrub and the length of the plant is 1 m to 1.5 m tall. The stem of this is green or brown. Leaves are larger and divide into 3 to 5 lobes. Twigs and leaves are densely heavy. Seeds have extensive hair and thick fuzz. Boll is round in shape and contains 5 to 7 seeds per loculus with 3 to 5 lobular.

 

CHARACTERISTICS OF COTTON FIBRE:

Cultivation for commercial purposes, cotton fibre’s hair is classified into two parts:

• Fuzz
• Lint

In the early stage of growth, both are almost identical in appearance as both arise from the same layer of epidermal cells.

FUZZ:

Fuzz are formed when seeds are detached from the fruiting body which contains both seed and lint. In that separated seed, the seed coat has a hairy structure which is known as a fuzzy seed and that hair growth-like structure is called Fuzz. These are shorter in length. The length gained by the fibre is only up to 10 millimetres. The wall of this fibre is thick due to the deposition of cellulose in the secondary wall which prevents the formation of a twist as a result it lacks a twisted structure.

LINT:

 These are longer and gain a length of up to 45 millimetres. Hair is distinct due to its twisted structure. They have thin walls due to less deposition of cellulose in the cuticle. These fibres are finer than the others and due to this property, it is extensively used in the manufacturing of fabrics.

 

PROPERTIES OF COTTON FIBRE:

Cotton fibres exhibit two types of properties:

1. Physical properties
2. Chemical properties

Physical properties of cotton fibres:

Some physical properties are pointed out-

• It shows medium heat prevention power
• Medium abrasion resistance
• Low resiliency
• Cream or white in colour
• Density is more than linen but less than silk and wool
• Low elasticity

Chemical properties of cotton fibres:

Some chemical properties are pointed out-

• When acting with alkali it does not damage cotton fibres and hindrance power is good.
• When acting with strong acid it damages the fibre whereas weak acid does not damage it.
• In presence of strong oxidizing bleaching, cotton is converted into oxi-cellulose.
• Ultraviolet rays of sunlight convert cotton into oxi-cellulose.
• Affinity to colour is good.

PROCESSING OF COTTON FIBRES:

There are various steps in the processing of cotton fibre:

1. DEFOLIATION: It is the process of removing the leaves from the cotton plant.
2. MACHINE HARVESTING: A single machine harvests the cotton and removes large contamination from the cotton fibres and forms it into bales.
3. SEPARATING: A cotton gin separates cotton seeds from bolls and removes dirt or trash.
4. TRANSFERRING: The cotton is transferred to a textile production facility.
5. CARDING: Carding is the process of forming cotton fibres into long strands.
6. SPINNING: The strands are spun to create yarn.
7.  DYEING: This cotton yarn may then be subjected to a variety of chemical treatments. It may be dyed.
8. WEAVING:  In this, the cotton fibres are woven into a particular type of textile material such as bedsheets, shirts, jeans, etc.

ADVANTAGES OF COTTON FIBRES:

• It braces communities and farmers.
• Naturally feasible
• Comfortable
• Low maintenance
• Odour free
• Versatile
• High tech
• Hypoallergenic

DISADVANTAGES OF COTTON FIBRES:

• Burns easily
• Affected by mould
• Easily wrinkles
• Shrinks in warm water
• Fainted by the sun and perspiration
• Natural fibre wears out faster

To sum it up, next time you wear a cotton shirt or a dress, do appreciate these soft, cushy, fluffy and cool staple cotton fibres. To know more, keep reading!

Team MBD

How Cotton is Processed in Factories | How It’s Made- Watch here: (1) How Cotton is Processed in Factories | How It’s Made – YouTube