Jute fibre




Дата канвертавання18.04.2016
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Jute fibre:

It is a member of bast fibres. Jute is derived from plant and in the plant it forms continuous strand and run the entire length of the plant stem. Among all bast fibres jute is top of the list.


Why jute is called bast fibre:

Bast fibres are obtained from stem, bark or leaf of certain vegetable plants. Jute fibre is also obtained from the bark of jute plants. So it is called bast fibre.


Examples of bast fibres:

Jute, Flax


Jute growing countries:

Jute is cultivated on a large scale in Bangladesh (Mymensingh, Rangpur, Dhaka, Faridpur, Jessore, Pabna and Comilla etc), India (East Bengal, West Bengal, Coochbihar, Tripura, Bihar, Assam and Orissa). Jute is also cultivated in the Nile Valley, Nigeria and other parts of Africa, Brazil, Indo-china, Japan and Myanmar. But the quantities produced in these countries are very small and quality is not good.



Botanical Classification of jute plant


  1. Corchorus Capsularis,

  2. Corchorus Olitorius,

  3. Corchorus Fuscus,

  4. Corchorus Decurnanglatus,

  5. Corchorus Monpoxensis.

  6. Corchorus Japanicus.

Among above the first two types are cultivated the most. There are about 40 species of jute, plants. Jute fibre is obtained from the two types of jute plants.



Difference between Corchorus capsularies (white jute) and Corchorus Olitorius (Tossa jute).


Corchorus Capsularies

Corchorus Olitorius

a) The leaves are thin and light green in colour with serrated edges.

a) The leaves are lovely green in colour.

b) The leaves taste better, hence the name “TEETA PAT” in some localities.

b) The taste of the leaves is not better, hence the name “Mitha pat” in some localities.

c) The bark of the stem is brown to green in colour.

c) The bark of the stem tends to be purple in colour.

d) Colour of flowers is yellow.

d) Colour of flowers is depper yellow and the flowers are large in size.

e) Seed pods are short and almost circular in shape.

e) The seed pods are long and cucumber like in shape.

f) Seeds when matured are brownish in colour.

f) Seeds when matured are grey in colour with a bluish tinge.

g) The plants flowers in the monsoon reason and the fruits ripes in September and October.

g) The plants flower in the monsoon reason and fruits ripes during October and November.

h) Fibres from this variety are known as “white jute” in the trade.

h) Fibres from this variety are known as Tossa in the trade.

i) Locally it is known as “Sutipat”.

i) Locally it is known as “Bogipat”.


Requirement for successful cultivation and growth of jute


  1. Temperature:

High temperature up to 950 F with a minimum 800F during the period of growth.


  1. Soil:

Well penetrative soil of fairly fine texture.


  1. Seeds:

The seeds should be suitable or suitable seeds should be select.


  1. Rainfall:

Rainfall should be over 40inches. This rainfall should be so distributed that while the young plants have sufficient moisture, the bulk of the fall should take place when the crop is more matured.


  1. Supply of water:

A sufficient supply of water for retting the plants and washing the stripped fibres.


  1. Supply of labor:

There should be sufficient and suitable supply of labour to handle the crop at the proper time.


  1. Facilities for placing the fibres in the market.


Character of soil:

  1. The rich sandy soil of high lands is the best quality for the cultivation of jute in respect to strength and colour. In this type of land corchrous olitorius variety is cultivated. Preparation of land begins often winter crops and sowing in March and April.

  2. The bulk of jute crops is cultivated in char land.

  3. Low lying lands are the best, for jute can be prepared in large quantity.


Cultivation of jute

  1. Preparation of land:

Jute seeds are small; therefore a very fine preparation of land is necessary. The country plough made of wood is used generally for ploughing the land. The land should be ploughed and cross-ploughed at least 6 to 8 times to break down the lumbs of earth and level the ground.


  1. Sowing methods:

There are generally two methods of sowing. i) Broad cost sowing, ii) Line sowing.


  1. Time of sowing:

Chorchorus capsularus variety can be sowing any time after January. But depends upon the position of lands and weather conditions. Chorchorus olitorius variety should be sown before March.


  1. Weeding and thinning:

When the plants are about 1-2inches high first weeding carried out. When plants are 3-4 inches high, weeding and thinning are carried together and again carried out when plants are 2-3 feet high. In between this period weeding is carried out if necessary.



  1. Jute posts and diseases:

A small insect known as “Jute aplam” bores hole in jute stem and lay eggs. Also other insects feed on leaves of plant “Flingus” also causes stem and root of plant decay. “Chlerosis” or “Yellowing” of leaves is also observed.


  1. Harvesting time:

Jute plants may be harvested from the bud stage until the young fruits have just yet. It also may be harvested when fruits have fully formed.


  1. Cutting:

Cutting of jute plants is usually done by hand with a sickle. The stalks are tied into small bundles and stacked on the field for 2days. During which time the leaves full of the stalk on the ground.


  1. Retting:

Retting is the process in which the fibre in the bark are lossened and separated for the

woody stalk due to the removal of pectins, gums etc. This is done by the combined action of

water and micro-organism.

During retting, disintegration of the tissues starts from the interior of the stem and

extend to the outside, liberating the fibre bundles from the wood. The presence of periderm (a

thin corky outer layer) on the stem surface hampers retting and lowers the fibre quanlity.




Defects of jute

The following are the defects generally found in jute:




  1. Specky jute:

Due to not rotted and washed properly.


  1. Rooty:

Due to under rotting of the root ends of the fibre.


  1. Croppy:

Due to careless steeping for rotting.


  1. Knotly:

Due to punctures in the growing plants.


  1. Dazed:

Due to over rotting or strong in moist condition.


  1. Heart:

Due to excess moisture in jute while baled.


  1. Hunka:

Due to non remove of hard bark from the fibre.


  1. Weak:

Due to over rotting.


  1. Mossy:

Due adhere to the fibre.


  1. Glossy:

Due to denoting the quality of a jute fibre.



  1. Sticky or woody:

Due to over retting of the lower part of the plant.

  1. Runners:

Due to careless steeping and washing.


  1. Flabby:

Due to over retting and careless stripping.

Grading of jute
By the term grading of jute we mean the assortment of raw jute according to their quality.

Fibre characteristics which influences grading of jute to higher or lower standard:


Length:

Long fibres which allow removal of roots leaving a good length for manufacturing purposes command a higher price short fibres of the same character medium qualities 6 to 8 feet long and better qualities over 8 to 12 feet long.


Strength:

Greater the strength, higher it is grading. When jute is stored in moist condition, its strength fails off. Therefore storage of jute in moisture reduces its strength as well as decreases it grading.


Lustre:

Better qualities have fairly high lustre, malt and rough surface indicates weak fibre.


Uniformity in colour:

This property is quite evident in better qualities. Inferior qualities are very irregular in their respect.


Color:

Best qualities are pale, white or silvery grey, common qualities are brownish or greenish and inferior qualities and roots are usually darker without any lustre.


Roots:

Base portion of the jute stems is more rigid and ahs a stronger supporting bark than the rest

of the stem. This is due to longer exposure of this part to the action of the sun and water. In high

grade sorting root portions are removed by cutting and baled separately known as bale cuttings.


Clearliness:

Clearliness of fibres is an essential factor for high grade. Adhering portions of bark and specks are undesirable which affect grading according to their degree of presence.




Grading of jute (Pucca jute):

White jute


  1. Bangla White Special (BW-S):

    • This jute are finest texture,

    • Very strong and very good luster,

    • Completely free from any defects,

    • Clean cut and well hackled (AvPuov‡bv) and entirely free from red ends.

  2. Bangla White –A (BW-A):

    • Jute of fine texture,

    • White to light cream color,

    • Strong, very good luster,

    • Completely free from any blemish(`vM),

    • Free from red ends and fault.

  3. Bangla White-B (BW-B):

    • Light cream to straw color,

    • Jute of good texture,

    • Strong and good luster, clean,

    • Free from blemish,

    • Well hackled and free from red ends.

  4. Bangla White –C (BW-C):

    • Light grey to light reddish to straw color

    • Jute of sound strength, avg. luster,

    • Free from croppy or hard gummy(wPUwP‡U) tops,

    • Well cut, free from black roots,

    • Red soft end permissible.

  5. Bangla White –D (BW-D):

    • Jute of any colour.

    • Average strength, occasional(gv‡Sg‡a¨)bark (Qvj) & specks are permissible,

    • Slightly croppy and gummy tops are permissible,

    • Red ends are permissible(MÖnY‡hvM¨Zv) .

  6. Bangla White –E (BW-E):

    • Jute of any colour.

    • Avg. strength, but free from prevished (cuPv) fibres,

    • Free from unrotten jute & stick.

    • Bark and hard jute permissible.



Tossa jute


  1. Bangla Tossa special (BT-S):

    • Uniform golden/reddish color,

    • Finest texture,

    • Very strong, very good luster,

    • Clean cut & well hackled,

    • Completely free from any defects.




  1. Bangla Tossa –A (BT-A):

    • Uniform silver grey to golden color,

    • Fine texture, strong and good lusture,

    • Clean cut & well hackled.

    • Completely free from any blemish.




  1. Bangla Tossa –B (BT-B):

    • Light to medium grey color,

    • Clean, good texture, avg. lustrue,

    • Cleaned cut and well halked

    • Free from any blemish.



  1. Bangla Tossa –C (BT-C):

    • Mixed color

    • Avg. strength,

    • Occasional bark and soft speck allowable but free from runners.

    • Slightly croppy and gummy tops permissible,

    • well cut and halked

    • Free from black root ends or tops.




  1. Bangla Tossa –D (BT-D):

    • Mixed color,

    • Avg. strength,

    • Occasional bark and specks allowable but free from runners.

    • Croppy and gummy tops permissible.

    • Rough cut and halked but free from black root ends.

  1. Bangla Tossa –E (BT-E):

    • Avg. color,

    • Avg. strength,

    • Free from unrotten jute and stick and rotten fibres.

    • Rough hackled,

    • Bark & dark centre permissible.



Kutcha Bale is graded as follows


  1. Tops:

    • Very strong fibre,

    • Excellent color & luster,

    • Free from all defects.




  1. Middles:




  1. Bottoms:

    • Medium strength,

    • Free from hard centered jute.




  1. B-Bottoms:

    • Medium strength

    • Not suitable for higher grade yarn.




  1. C-Bottoms:

    • Medium strength

    • Any color

    • Free from runners and croppy ends.




  1. X-Bottoms:

    • Weak, harsh,

    • Free form entanglement jute and stick.




  1. Habi-jabi:

    • Entangled jute of any sort

    • Free from dust and cuttings.


Classification of jute
Classification of jute according to their suitability of spinning and weaving.


    1. Jat:

The fibres of this variety are generally hard, even and of well defined texture, spin into the first count and involve minimum waste, this is the best class of jute grown in parts of Mymensingh, Dhaka and Comilla.


    1. District:

The districts quality jute which is next to the jat a soft hairy and light. District jute of two types. i) Hard district, ii) Soft district.

The jute of hard district is better than the soft district. Hard district jute grows is the district of Faridpur and jute grow in the district of Noakhali, Pabna, Barishal, lower Comilla, part of Dhaka.




    1. Northern:

This type of jute is grown in the district of Rajshahi, Dinajpur, Bogura and Pabna etc in between the river Gauges and Brahmaputra. This variety of jute is most hairy and soft and has very littlie lustre. Some qualities are heavily rooted and dark colour.
Physical structure of jute:
The jute stands is bundle of individual fibre, held together by gums waxes and lignin. The cross-section of the fibre is polygonal in shape with sharply defined angles. Cell are thick. The lumen is large and the cross-section is oval. Longitudinally the lumen is irregular.
Molecular structure:
Jute is a cellulosic fibre. It’s repeating unit also cellulosic. Jute is composed of 65 percent cellulose and 35 percent natural waxes, oils and cements (lignin).
Ultimates:

    • Ultimates are connected each other to form a fibre structure.

    • It is 1.5 to 4mm in length,

    • 6-20 ultimates takes place in cross-section.


Lignin:

Lignin is a gum which joins ultimate one by one and gives a jat fibre. It harshes the fibre.




Fig: Lignin.

Pecto cellulose:

Cellulose fibre containing cotton and pectin is called pecto cellulose.


Ligno cellulose:

Cellulose fibre containing lignin is called ligno cellulose.



Macro-Structure of Jute:
The individual fibrils in the jute bundle are shortest. It is a weakest of the cellulosic fibre. Lumen is irregular in size.


  1. Ultimate length: 1.5 to 4mm.

  1. Diameter: 0.015 to 0.002mm.

  2. Length: 150 to 300cm (5-12ft)

  3. Length width ratio: 90:1 contain 6 to 20 ultimate in cross-section.

  4. Colour: Yellow to Brown to Grey


Chemical composition of jute:

Cellulose  65.2%

Hemicellulose  22.2%

Lignin  10.8%

Water soluble  1.5%

Fats and wax  0.3%


Draw the Anatomy (microscopic) of Jute fibre:

Fig: Anatomy of jute stem.


Properties of Jute
a) Physical Properties:


    1. Specific gravity:

1.48

    1. Moisture regain:

13.75% (Standard), jute can absorb 23% moisture at humid condition.


    1. Tenacity:

3.5-5 g/d, loses strength during wet condition.


    1. Elongation at break:

1.8%

    1. Elastic recovery:

Almost no recovery.

    1. Resiliency:

Bad.

    1. Abrasion resistance:

Moderate.

    1. Dimensional stability:

Good.

    1. Effect of age:

If kept at dry condition it will last for indefinite time. Moisture deteriorates jute and loses strength with age.
b) Chemical properties of jute:


  1. Effect of Bleaching:

Not affected by oxidizing and reducing agent. Bleachable with such bleaching agents that are used for cotton bleaching.

Oxidizing agents: H2O2, K2Cr2O7

Reducing agents: Na2S2O4(Hydrose)


  1. Acids:

Easily damaged by hot dilute and cold concentrated mineral acids.



  1. Alkalis:

Resistant to alkalis. It can be scoured by strong alkali such as NaOH, Na2CO3(Soda ash) in a suitable temperature.


  1. Organic solvents:

Resistant to organic solvents.


  1. Resistant to sunlight and heat:

Poor sunlight resistance, scorches (cy‡o hvIqv) at high temperature and burns rapidly and produce ashes.


  1. Dye ability:

Good affinity to Basic dye, but light fastness (¯’vwqZ¡ / cvKv)(Color fastness to light) and wash fastness is poor (color fastness to wash).


  1. Biological properties:

Scoured jute has good to excellent resistance to micro-organisms and insects.


  1. Conductivity:

Moderate (gvSvgvwS) conductor of heat and electricity.
Microscopical properties


    1. Cross-sectional appearance:


Cross-section of fibre is polygonal in shape with sharply defined angles. Cell walls are thick, lumen is large and cross section is oval.





    1. L
      Externally the jute is smooth and lustrous. It has no joint ridges. Lumen shows irregular nickness in the cell wall; towards the end of the fibre lumen brodens out causing the cell wall become very thin.
      ongitudinally:



Fine structure jute


  1. Physically jute consists of bundles of fibres held together by hard coating substance.

  2. The individual fibre is made of a large no. of ultimate fibres cemented together by substances which have no regular shape.

  3. Usually 6-20 ultimate in each cross-section of a fibre with diameter 6-20microns and average length is 2.5mm.

  4. Cell walls are thick and in the centre of the wall is a hollow lumen.





Fibre bundle


Why emulsion is add in the jute?

Ans:


For high tenacity, less extension, high stiffness jute fibre is brittle and can holds less twist. So emulsion is added to make it soft.
Describe the present condition of jute in the world market?

Ans:


Jute and jute products are one of the most important exporting things of a progressive country. Chat, Galicha, Carpet, Clothes etc are made from jute fibre. The districts of Mymensingh, Rangpur, Dhaka, Pabna, Jessore and Faridpur produce a large quality of jute.

A few years ago, jute and jute goods is the highed exporting thing in the world market from Bangladesh. By exporting it, the economic develops in the highest point.

But the exporting of jute and jute goods has gone to very low because jute is not produced in so much and the buyers of different countries are not so careful to buy jute and jute goods and they try to import another thins in place of it. So the present condition of jute in the world market is not expectable.

Uses of jute



Jute is cheap and reasonably strong and is available in large quantities. Familiar uses for jute include the following: Sacks, bags, bundle, clothes, wrappings, bedding, foundations, boot and shoe linings, cargo and other separation clothes, cables, plastics, filter clothes, fire curtains, hand bag, upholstery, wall covering. Jute can also form the backing cloth for floor covering. In world trade market increasing its demand as jute bags for cheap means of packaging, synthetic hags polluted the environment but jute fibres are friendly oriented to environment. So, day by day the demand of jute fibre is increasing rapidly.




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