BAST FIBERS Botanical name is “Dicotyle Denous”. Bundles of strands that over lap each

other. Fibers made up of long thick cell

walls which overlap one another , cemented by non cellulosic material to form continous strands.

QUEEN OF BAST FIBERS

It grows in hot as well as in cold areas. Growth of flax is in the areas where

rain fall is in greater amount. Flax fibers come from the stem of an

annual plant “LINUM USITATISSIMUM” which grows in sub-tropical regions.

Firstly it was known as Linen. With growth of cotton industry interest was lost for flax industry.

FLAX

Probably the 1st plant which was used by man. In Egypt and Switzerland its cloth was prepared

and dyed. Now a days it is cultivated in Europe, England,

France, Germany etc. As a source of oil, the flax plant is grown in

USA, Canada, Argentina but the output of fiber from these countries is relatively insignificant.

Soviet Russia grows fiber and oil. 1,875,018 world production

PROCESSING Natural, Cellulosic, Bast fiber is annual

plant grown once in a year. 3-4 months for harvesting. 3-4 feet height of plant. Plants are planted closely to avoid branches. Flowers appear, mature plant is pulled out

from the roots manually or mechanically. After this flax is allowed to dried. 1/3rd of stem consist of fibers.

RETTING

Processing Breaking and Scutching: scutching rollers break &

separate woody portion. Hackling: straightening and cleaning fibers by comb.

Coarse fibers removed. Long fibers LINE and short fibers TOW.

Carding: Drawing: 4 to 8 slivers Spinning: For coarse yarn dry spinning, Finer wet

spinning. Dyeing:

Fibre morphology

Macro-structure Flax is a thick, regular fibre with subdued luster. Length is from 10 – 100 cm; average length is 50

cm 3-6 cells constitute fibre cross-section. Fibre cells

are about 25mm long and 10 µm thick. Average fibre thickness ranges from 40 µm – 80 µm.

Flax fibre length is of considerable significance. For longer flex it is about 15000:1 and for short fibres the length to breath ratio is 1500:1 or less.

The colour of flax changes from light blond to grey blond.

The subdued luster is due to its longer fibre surface which is coated with a film of wax.

Microscopic appearance

Cross marking know as nodes give them characteristic microscopic appearance. There may be 800 nodes in a single flex fibre.

Fiber Properties Tanacity

Flax is a strong fiber because its very crystalline polymer system forms more hydrogen bonding than cotton polymer. Its tenacity also increases in wet condition same as cotton.

Elastic natureThe very inelastic nature is due to its crystalline polymer system. Being a stiff fiber it resists bending and flexing. The crispiness of its handle is due to its ability to absorb moisture rapidly. The wrinkling and creasing which in linen fabrics is due the stiffness of fibers; when fibers are bent, the hydrogen bonding between the polymer chains breaks and reformed at the new positions due to which fiber is unable to come back to its original position.

Hygroscopic nature like cotton it has a good moisture absorption

capability

Fiber properties Density Fiber density is 1.5 g/cm cube and is

considered as heavy fiber. Thermal properties

flax has the best heat resistance and conductivity of the all common used textile fibers.

Moisture regain: It is 12%. Elongation: dry state 1.8% and wet state 2.2% Heat Action: It is good conductor of heat.

Chemical properties

Action of acids: 80%dissolved in

H2SO4. strength reduces. Effects of alkalies: Effect of organic Solvents: Insects: Micro organisms:

USES

Sail and tent cloth Shoe threads Sweing thread Book binder threads Table cloth Handkerchiefs Waste flax