1. Study of Natural fibers
Text book of Pharmacognosy, by T.N.
Vasudevan and K.S. Laddha, vrinda
publication, Page no.183-193

2. Introduction
• Fibres may be defined as any hair-like raw material
directly obtainable from animal, vegetable, or mineral
source and convertible into nonwoven fabrics such as
felt or paper or , after spinning into yarns, into woven
cloth.
• A natural fibre may be further defined as an
agglomeration of cells in which the diameter is
negligible in comparison with the length.
• Although nature abounds in fibrous materials ,
especially cellulosic types such as cotton , wood,
grains, and straw, only a small number can be used for
textile products or other industrial purposes.

3. Types of Fibers
• Natural
– Originate from natural sources
– Plant (cellulosic) or animal (protein)
• Manufactured, synthetic, or man-made (terms
interchangeable)
– Originate from chemical sources
– May also be from regenerated or recycled sources

4. Natural Fibers
• Natural fibers are textile
fibers made from plants or
animals
• Cellulosic (from plants)
– Cotton
• From cotton plants
– Flax (linen)
• From flax stems
• Protein (from animals)
– Silk
• From cocoons of
silkworms
– Wool
• From fleece (hair) of
sheep or lambs

5. Classification

6. Absorbent cotton
• SYNONYMS: Raw cotton, purified cotton, absorbent cotton.
• BIOLOGICAL SOURCE: Epidermal trichomes of the seeds of cultivated species of
The Gossypium herbaceum and other species of Gossypium (G. hirsutum, G.
barbadense) freed from impurities, fats and Sterilized, belonging to family
Malvaceae.
• GEOGRAPHICAL SOURCE: United States, Egypt, some parts of Africa, and India.
• DESCRIPTION:
• Colour White
• Odour Odourless
• Taste Tasteless
• Shape These are fine filament like that of hair, which are Soft and unicellular.
• Size 2.2-4.6 cm in length and 20-35 micron diameter
• CHEMICAL CONSTITUENTS:
• It consists of 90% of cellulose, 7-8% of moisture, wax, fat and oil 0.5% and cell
content about 0.5%. Purified cotton has almost cellulose and 6-7% of moisture.
• USES:
• Cotton is used as a filtering medium and in surgical dressing. Absorbent cotton
absorbs blood, pus, mucus, and prevents infections in wounds.

7. Jute
• SYNONYM: Gunny.
• BIOLOGICAL SOURCE: It consists of phloem fibres from the
stem of various species of the Corchorus; C. capsularis Linn, C.
olitorius Linn, and other species like C. cunninghamii, C. junodi
etc., belonging to family Tiliaceae.
• GEOGRAPHICAL SOURCES: West Bengal and Assam.
• Description: They are tall, usually annual hers, reaching to a
height of 2-4 m, unbranched and if branched it has only a few
side branches. The leaves are alternate, simle, lanceolate, 5-
15 cm long and a finely serrated or lobed margin. The flowers
are small (1.5-3 cm in diameter) and yellow, with five petals;
the fruit encloses many seeds in the capsule.

8. Jute
• Preparation:
Cut stem
and tied in
small
bundles
Kept in
water for
retting (10-
30 days) for
separation
of fibers
from wood
Cover with
weeds to
avoid direct
sun contact
Submerge
with heavy
load like
breaks,
stones..
Ends of
stem are
bitten
Hold free
ends of
fibers and
clean by
jerking
them in
water
Dry under
sunlight for
2-3 days

9. Jute..
• CHEMICAL CONSTITUENTS: Jute fibers are compose primarily of the plant
material, cellulose and lignin. Jute is composed of about 50-53% cellulose,
nearly 20% of hemicelluloses and 10-11% of lignin along with other
constituents like moisture NMT 12-13%, fats, wax and ash contribution to
1% each.
• USES: It has a large range of use (about 1000 uses). It is listed as the
second most important vegetable fibre after cotton. Jute is used chiefly to
make cloth for wrapping bales of raw cotton, in the preparation of sacks
and coarse cloth, they are also woven into curtains, chair coverings,
carpets, Hessian cloth very fine threads of jute can be made into imitation
silk and also in the making of paper. It is also used in the manufacture of
tows, padding splints, filtering and straining medium. Jute is also used for
the preparation of coarse bags.

10. Flax
• Synonym: Flax (also known as common flax or linseed),
• Biological source: flex consist of pericyclic fibers with the binomial
name Linum usitatissimum, is a member of the genus Linum in the
family Linaceae.
• Discription: Cultivated flax plants grow to 1.2 m (3 ft 11 in) tall, with slender
stems. The leaves are glaucous green, slender lanceolate, 20–40 mm long
and 3 mm broad.
• The flowers are pure pale blue, 15–25 mm diameter, with five petals.
The fruit is a round, dry capsule 5–9 mm diameter, containing several glossy
brown seeds shaped like an apple pip, 4–7 mm long.
• Preparation: same as that of jute
• Chemical constituent: 64% cellulose, 17% hemicellulose and 2% lignin
• Formerly used in maufaturing of lint but now replaced by cotton

11. Hemp
• Biological source: Pericyclic fibers of the stem of Cannabis
sativa belonging to family Cannabinaceae
• Preparation: similar to jute
• Description: Fiber strands are ribbon like over 1.8m long.
Individual fibers 35-40mm in length and 22 µ in diameter.
Cylindrical with surface irregularities in the form of frequent
joints, longitudinal fractures and swollen tissues. Ends of
fibers are blunt and occasionally show lateral branching.
Colour: yellowish, greenish, grey or dark brown.
• Chemical constituens: 67% cellulose, 16% hemicellulose and
small amt of lignin.
• Uses: Making carpets warp, canvas, tarpaulins, webbings,
sacking, twines, ropes, cables etc. No pharmaceutical use.

12. Silk
• BIOLOGICAL SOURCE: Fibres obtained from the cocoons
spun by the larvae Bombyx mori Linn., belonging to family
Bombycidae/Moraceae.
• GEOGRAPHICAL SOURCE: China, France , Iran, Italy, Japan,
and India.
• DESCRIPTION :
• Colour : Yellow
• Size : 5 to 25 microns in diameter and 1,200 metre in length
• Appearance: Fine, solid, smooth to touch
• Solubility: Soluble in cuoxam , in cold dilute sulphuric acid.
• Extra features: Hygroscopic in nature and has good elasticity
and tensile strength.

13. Silk
• Preparation:
• The silk moth lays thousands of eggs.
• The silk moth eggs hatch to form larvae or caterpillars, known as silkworms.
• The larvae feed on mulberry leaves.
• Having grown and moulted several times silkworm weaves a net to hold itself
• It swings its head from side to side in a figure '8' distributing the salivar that will
form silk.
• The silk solidifies when it contacts the air.
• The silkworm spins approximately one mile of filament and completely encloses
itself in a cocoon in about two or three days. The amount of usable quality silk in
each cocoon is small. As a result, about 2500 silkworms are required to produce a
pound of raw silk.
• The silk is obtained by brushing the undamaged cocoon to find the outside end of
the filament.
• The silk filaments are then wound on a reel. One cocoon contains approximately
1,000 yards of silk filament. The silk at this stage is known as raw silk. One thread
comprises up to 48 individual silk filaments.

14. Silk
• CHEMICAL CONSTITUENTS: Silk mainly consists of
protein known as fibrion.
• Fibrion is soluble in warm water and on hydrolysis
yields two main amino acids, glycine and alanine.
• USES: Silk is used pharmaceutically in the
preparation of sutures, sieves, and ligatures.
• The ‘stiff silkworm’ (dried body in the four to fifth
stage of larva, which dies due to infection of the
fungus Beauveria bassiana) is used in the traditional
Chinese medicine.

15. Wool
• Biological source: Hairs from the fleece of the sheep, Ovis
aries Linn. Belonging to family Bovidae
• Description: Individual fibers are solid, 2-50 cm long and 5-
100µ in diameter. Fibers consist of central narrow core of
rounded or polyhedral cells, surrounded by wide cortex of
nucleated spindle shaped fibers.
• Chemical constituent: Protein Keratin containing C, H, O, N
and S. S containing protein is about 3-4%
• Uses: Filtering and straining medium and for manufacturing of
dressing like flannel, domette and crepe bandages

16. Wool• Preparation:
Shearing
• Hairs are removed from sheep
• Greaded according to fineness
Cleaning
• Clean dirt and wool-grease by treatment with soap and sodium carbonate
Washed
• Washed in hot water
• Dried and bleached with sulphur dioxide or hydrogen peroxide
Carded
• Carded and processed to form wool thread or yarn

17. Viscose rayon
• SYNONYMS: Rayon, regenerated cellulose
• BIOLOGICAL SOURCE: Viscose is a orange-red aqueous
solution of sodium cellulose xanthogenate obtained by
dissolving wood pulp cellulose in sodium hydroxide solution
and treating with carbon disulphide.
• DESCRIPTION:
• The rayon is a white, highly lustrous fibre. Its tensile strength
varies from two-third to one-and-a-half times that of cotton.
When wetted, it loses about 60% of its tensile strength. It has
a proportionately greater loss than is found with cotton. The
fabric is a water-repellent (e.g. cotton crepe bandage).
• Uses
• Viscose rayon is used to manufacture fabrics, surgical
dressings, absorbent wool, enzyme, and cellophane.

18. Viscose rayon
• Preparation:
• remove lignin and resisns
• Washed, bleachedChemical treatment
• Macerated with caustic soda
• It gives alkali celluloseWood cellulose
• Alkali cellulose soaked into alkali for 24 hrs
• Then treated with carbon disulphideCellulose Xanthate
• To remove particular matter and air bubbles by
applying vacuumFiltration
• Forced through spinneret as a jet with fine nozzles
into a acid bathFormation of filament
• Filaments are twisted to form thread
• Then spun into yarnFormation of Yarn

19. Asbestos
• It is fibrous mineral composed of magnesium
silicate with some calcium silicate and small
percentage of iron and aluminium.
• Fibers vary in length from 1-10cm
• Colour: white, yellow or green
• They are unaffected by all the usual reagents
used for the identification of fibers
• On heating do not fuse (distinction from glass
wool)
• Uses: used as filtering media and making heat
resistant hand gloves

20. Glass wool
• Synonym: Glass fiber, fiber glass
• Source: glass wool consists of glass spun into
fine solid fibres
• Description: Transperant, lustrous, hard fibers
which are brittle.
• Uses: use for filtration of corrosive liquids such
as mineral acids. Use in heating mantles
(electric)and refrigerator(Heat) as insulator.

21. Glass wool
• Preparation:
• Made from
sand (Silica)
• With oxides of
calcium,
magnesium,
aluminium and
boron
Melting
• Melted into
marbles
• Feeding in
fiber-drawing
machine
Feeding
• Marbles are
melted and
forced through
small nozzles
• It gives filament
on cooling
Filament
formation