Types of Cotton

Cotton can be classified into various class according to commercial, botanical, staple length, maturity. All kinds are given briefly below:

According to Botanical classification:

(a) Gossypium harbaceum: This kind is usually cultivated in Asian Countries like India, Pakistan, China and Bangladesh. Its length is from 0.8 inches to 1 inch, height of the plant is of 3 feet to 6 feet, flower color is yellow.

(b) Gossypium hirsutum: This kind is cultivated in North and South America (90% of world production). Its length is from 0.5 inches to 1.20 inches, height of the plant is from 6 feet, flower color is Red.

(c) Gossypium peruvianum: This is mainly produced in Peru and other South American countries.

(d) Gossypium arboretum: It is widely cultivated in America, also in India, Pakistan,

Russia

. Its length is from 0.5 inches to 1.20 inches, height of the plant is fro 10 feet to 15 feet.

(e) Gossypium barbedense: This type is mainly produced in Egypt and Sudan which is known as Sea Island cotton. It is a high quality cotton but production is low (8% of world production). Its length is from 1.2 inches to 2.4 inches, height of the plant is of 6 feet to 15 feet, flower color is yellow.

According to commercial point of view:

(a) Sea Island cotton: This is the highest valuable cotton in the market for its high quality. Sea Island cotton grows on the coast of the Gulf of Florida, Barbados and in other adjacent islands where the climate is suitable. The length of the cotton is from 1.5 inches to 2.5 inches and diameter is 0.017nm. It can be used for spinning finest count of about 2.94Tex and sometimes mixed with silk. It is famous for its uniformity, maturity, highly developed luster, twist, soften and silk like texture. Its color is white to cream. It was also grown on the uplands of Georgia, where the quality was inferior and was soon surpassed in commercial production by another native American species, Upland cotton (Gossypium hirsutum), which today represents about 95% of U.S production.

(b) Egyptian cotton: There are two kinds of Egyptian cotton:- one brown and the other is white. Egyptian cotton is usually produced in Egypt with extra long staple length. It is very regular and contains few immature or dead fibres. The staples of Egyptian cotton can range from 1 .5 inches to 1.75 inches. Their long length (about twice the size of other cotton fibers) allows them to be spun into very fine yarns but not more than 2.95Tex. These yarns are soft and lustrous yet are very strong and durable.

(c) South American cotton: This has a staple length of 1 inch to 1.5 inches and diameter is .0195mm. It is very suitable to mix with regenerated man made fibre.

(d) American cotton: This is cultivated in the United States. Its staple length is 0.9 inches to 1.25 inches and diameter is 0.021mm. It has good natural color and cannot be used for the extremely fine counts(8.43tex).

(e) Indian cotton: This is short fibre of 0.6 inches to 0.8 inches. Therefore, it is only suitable for producing coarser counts.

(f)

China

cotton: This is the lowest commercially acceptable grade. Its staple length is short and its from 0.5 inches to 0.7 inches. Its twist is not highly developed and rather than harsh. It is not suitable for spinning a good yarn and is usually used in mixture with better quality.

According to fibre length:

(a) Long staple: This is the best and finest quality and has luster. Length of the cotton is longer than the others and it’s from 1 inch to 2.5 inches (25-65mm). Diameter is 10-15 microns. Sea Island cotton, Egyptian, American pima cotton etc. are example of long staple cotton.

(b) Medium staple: This fibre is medium grade, has medium strength and luster. Its length is from 0.5 inches to 1.3 inches (12-33mm) and diameter is from 12 microns to 17 microns. American upland and Peruvian cotton etc. are the example of medium staple.

(c) Short staple: Short staple cotton fibre is low grade coarser fibre, low strength no or little luster. This type of fibre has a length from o.375 inches to 1 inches (9-26mm) and diameter is from 13microns to 22microns. Asiatic cotton and Indian cotton are the good example of short staple cotton.

According to maturity:

(a) Mature fibre: We know mature fibre has well developed cell wall and very small lumen. Like that mature cotton has small lumen and it is the best in quality.

(b) Immature fibre: Fibre with thinner secondary cell wall, larger lumen is Immature fibre. They cannot exhaust the dye molecules properly in dyeing or printing. As a result, they produce uneven shade during dyeing.

(c) Dead fibre: Dead fibre has a only a primary cell wall. The lumen occupied the bulk of fibre. They remain undyed in dyeing.