FLAX
Flax is a bast
fibre found in the stem of the plant 'Linium
usitatissium' The plant is cultivated in cold and humid
condition So the plantation is centered in cold countries. The major source of
supply of flax is from old U.S.S.R. The other countries which have flax growing
areas are North Ireland, Egypt, Japan, Argentina, Brazil, France, USA,
Australia, Canada and New Zealand
CULTIVATION
Like jute, flax
is an annual plant .The plant from which the fibre extracts grows in moist and
cold condition. The plant grows up to 170 cm in height and 1.5 of cm dia. The
tree is matured by changing its color from green to yellow. After maturity, it
is harvested for the extraction of the fibre Haryesting may be done when
(i) Flowering is almost over and the stalk is
green,
(ii) the fruit has set, or
(iii) The seed
pods have ripened and the stalk is yellowish brown. Initial harvesting gives
poor yield with soft fibre.
Late
harvesting gives a coarse fibre with higher yield. So harvesting will be better
when the seed pods have ripened.
After harvesting, the plants are allowed to
lie in open field for a week or so when all the leaves and branches come out of
the tree. Then the plants are bundle up and carried over to a place where they
are hackled this is an operation, in which the plants are continuously beaten'
against a rows of vertical iron spikes to remove the impurities like leaves and
śmall branches.
PROPERTIES
Linen fibre is
the strongest fibre available from natural origin. This is due to presence of
higher crystalline regions like 80; 90 %. The average length of the fibre
varies from 90 cm to 125 cm having an average diameter of 14 to 25 microns. The
fibres are round to polygonal with a small lumen. Tensile strength of the fibre
varies from 6.5 gm/den to 8.0 gm/den. The density is 1.50 gm / cc . The
moisture regain is 12 % . Due to high crystalline areas, the fibre strength is
not sensitive to moisture i.e., the wet strength and dry strength is same.
These fibres
are resistant to micro-organisms like fungus, alkalis like sodium carbonate,
potassium carbonate at boil. The fibre is resistant to dilute acids at cold and
organic acids. However, hydrocellulose is formed due to the hydrolysis action
of dilute acids at boiling conditions or strong concentrated mineral acids. Oxycellulose
is generally formed by the action of oxidizing agents.
