In the form of spinner’s package
Warp preparation Weft
preparation
Winding (cone, Cheese) Winding (Cop,pirn)
Warping(pre beam,warp) Weaving
Sizing (weavers beam)
Drafting, Drawing,Denting,
Weaving
Flow chart of processing
Textile Chemical Processing for the
Fibres (Preparatory Operations)
• The fabric collected from various weaving setups,
can not be used directly for manufacturing
various textile products.
• There are number of impurities present in the
fabric such as dust, dirt, oil stains, oil and waxes,
starches or other sizing materials, seed particles,
and natural coloring materials.
These impurities can be classified as.
I. Natural Impurities &
II. Added Impurities
Objectives of
pre treatment
The main objectives of preparatory treatments
of textile materials are,
1. To remove all the impurities, both naturals
and those added during production that may
interfere in subsequent dyeing or finishing
process.
2. Improve the ability of the fibers to absorb
water, dyes solutions and chemicals.
3. Impart proper brightness or whiteness to
fabrics according to need, especially when
brilliant or pastel shades are desired.
Preparatory process
Important Preparatory Steps for Cotton Fabric
• Singeing
• Desizing
• Scouring
• Bleaching
• Mercerizing
SINGEING
• Singeing is a process of burning off protruding
fibers from the surface of the yarn of the fabric
in order to improve the lustre and
Smoothness of the material.
Types of singeing:
• Hot plate singeing machine
• Roller singeing machine
• Gas-singeing machine
DESIZING
• The removal of added size material in process of
sizing is known as desizing.
Methods Of Desizing
Hydrolic Oxidative Novel
Rot steep Chlorine Solvent
Enzymatic Chlorite Desizing 2000
Acid steep Bromite LT plasma
Treatment
SCOURING
• The oils and fatty acids of inorganic compounds
form a layer on fabric which are hydrophobic and
affect the absorbency of cloth. the process by
which the water resistant layer is removed is
known as Scouring.
• Scouring Processes for cotton:-
1.The lime soda process
2.Caustic-soda boil
3.Treatment with soap and soda ash
4.Enzyme scouring
BLEACHING
• Bleaching is a process by which the natural
colouring matter and any other colouring
matter is removed from natural fibers or
process discoloration from man-made
fibers.
• Classification of Bleaching Agents:
1. Oxidizing bleaching agents
Cl₂, H₂O₂, Na₂O₂, K₂S₂O₈, HOCl, KMnO₄, O₃
2. Reducing bleaching agents
So₂, Na₂SO₃, Na₂S₂O₄, H₂SO₃, NaHSO₃
Bleaching Reciepe
1. Desizing
0.3% Desize soln
0.4% Soap soln
2. Hot wash
4.5% NaoH boiling
H₂O₂ 1%
Stabilizer 0.25%
3. Bleaching
Bleaching 20gpl
Cold wash- 2
rounds
HCl 1%
Soda 0.5%
Mercerization
• Mercerization process was invented by John Mercer.
• In the Mercerization process, cotton fabric or yarn is
treated with a cold concentrated solution of sodium
hydroxide for one minute or less. In this process
cotton fibers swell, untwist and their bean shaped
cross section changes into a round form
Mercerization improves the following properties of the
cotton fabric.
1. Strength would be increased to 15-25%.
2. Enhanced luster.
3. Greater affinity to water, dyes and other chemical
finishes.
4. Shrinkage control in both the direction of the fabric.
Dyeing
• Dyeing is by far the most widely used
means of applying color to textiles.
• Dyes, by definition, are soluble in the
medium in which they are applied, and the
medium is almost always water.
Immerse Textile in
Dye-bath
Apply Heat, Time,
Chemicals to Drive
Dye into Textiles
Rinse to Remove
Surface Dye
All Dye is in Bath
Most of the Dye
Now on Textiles
Unfixed Surface
Dye Removed
Classification of Dyes
Dyeing Can Be Done at Different Stages:
• Fiber Stage • Yarn Stage • Fabric Stage • Garment Stage
• General Principles and Terms Met in Dyeing
1) Dye Exhaustion – This describes how much of the total dye
applied resides on the fiber rather than in the dye liquor.
2) Equilibrium – This is when the final or equilibrium degree of
exhaustion has been reached. If the dyeing is allowed to proceed
under the same conditions for a longer time, the shade of the
dyed goods will remain the same.
3) Levelness and Leveling Power - levelness depends on:
» Liquor ratio – The leveling power increase as the LR increases as
there is more dye in the bath
» Substantivity – Low substantivity favors leveling
» Temperature – Higher temperature give more level dyeing
» Time – Longer times give more level dyeing
Piece Winch
(or beck) Dyeing
• Fabric pieces are sewn end to end and this
rope-like form is dyed in a relaxed state.
• It is most widely used on knitted, woolen
and worsted fabrics.
Piece Jig Dyeing
• Fabric is treated in open width and is
passed through the dye bath rather than
immersed in to a dye bath and this is
repeated.
• There is a degree of
tension on the fabric and
is therefore used on woven
fabrics and not knits.
Piece Pad Dyeing
• The dye solution is applied by
means of a padder and the
fabric in open form is run
through an open vat.
• The fabric is subject to tension, so
only selected fabrics can be dyed.
• Advantages: System can handle
thousands of yards and dye can be
added automatically to provide
consistency of dye color
Reactive Dyeing
The reactive dyes are water-soluble anionic dyes,
which react with hydroxyl groups of cellulose to
become covalently bonded to the fiber.
• The chemical reaction between a reactive dye and a
cellulose fiber takes place in the presence of a base
and can be summarized as follows
• Offers bright colors with very good colorfastness,
(particularly good washfastness and excellent light
fastness).
• Susceptible to damage from chlorine bleaches
VAT
The Vat dyes are insoluble organic compounds that are
not substantive to cellulose. The following steps are
involved in dyeing:
1) Reduction (Vatting): Prior to dyeing they are converted
to their soluble form (leuco soluble vat dye) by means
of reduction in the presence of a strong base.
2) Dyeing: In this soluble form, they are substantive to
cellulosic fibers, and can be applied to them.
3) Oxidation: Once inside the fibers, uniformly
distributed, the Vat dyes are then oxidized and
converted back to their original insoluble form.
4) Soaping: to achieve a stable shade.
VAT
• The soft water throughout the dyeing stage
is a must with Vat dyes, since the soluble
Leuco salts form insoluble salts with Calcium
or Magnesium ions as well as with transition
metals.
• A wide choice of colors with good to
excellent colorfastness is available, although
their lightfastness may be somewhat
inferior.
Direct
• Direct dyes are soluble anionic dyes.
• The Direct dyes are so called because they were the first dyes to
dye cellulosic fibers directly without the need for a pre-
treatment of the fibers with a mordant.
• The mechanisms by which direct dyes become attached to
cellulose is assumed to be through the formation of a large
number of weak attractions between the dye and the fiber.
• Direct dyes exhibit relatively good colorfastness to sunlight, and
some are considered to have excellent lightfastness. However
colorfastness to washing is poor and therefore not appropriate
for frequently washed apparel.
• The problem of poor washfastness can be improved to some
degree by formaldehyde after treatment.
Direct
Properties of Dye Stuff
SHRINKAGE CONTROL
FINISHES
• A reduction in the length or width of a fibre, yarn or fabric is
known as shrinkage. Growth occurs when a fabric increases
in dimension. It is essential to know the shrinkage of the
fabrics in both the directions ( Warp wise and weft wise) to
determine construction and design of garment
• Causes of Shrinkage
• Intermolecular structure of fibres
• Yarn twist
• Fabric construction (Yarns / inch)
• Weave / knit structure
Compressive Shrinkage
(Sanforization)
• In Compressive Shrinkage process, the fabric is
dampened and is placed on a machine
equipped with a continuous thick woolen felt
blanket. The blanket travels around a smaller
roller carrying the
• fabric with it as it
• stretches around
• the curve of the roller.
ETP
It is a process design for treating the industrial waste water for its reuse
or safe disposal to the environment.
• Influent: Untreated industrial waste water.
• Effluent: Treated industrial waste water.
• Sludge: Solid part separated from waste water by ETP.
Treatment levels:
1. Prelimnary
2. Primary
3. Secondary
4. Tertiary (or advanced)
• Treatment mechanisms:
1. Physical
2. Chemical
3. Biological
Conclusion
• I learnt all the techniques and process of
textile processing.
• This Internship help in knowing the various
machine used for processing.
• Due to secrecy act, all the data on recipe,
method & activities has not been supplied &
hence the data given regarding to this do not
resemblance to the actual data.
• The whole process is not possible to bind in
such a small frame as this report, hence our
effort spenton summarizing, not describing
them
References
• Textile chemical processing, Students Handbook Central Board Of
Secondary Education Shiksha Kendra, 2, Community Centre, Preet
Vihar, Delhi-110301
• Wet Processing Technology-Internship Report
https://www.scribd.com/document/294278091/Wet-Processing-
Technology-Internship-Report-pdf accessed on 28th, Jan 2018
• Textile Internship Report - arvind denim division
https://www.scribd.com/doc/104909847/2012-Textile-Internship-
Report-arvind-denim-devision
• Internship report on dyeing
http://www.assignmentpoint.com/science/textile/internship-report-
on-dyeing.html Accessed on 29th, Jan 2018
• Srini Venkatraman, 2006 Bureau Veritas
file:///C:/Users/user/Downloads/dyingprintingfinishing-
100504132149-phpapp01.pdf Accessed on 30/01/2018
Thanking you

internship Dyeing

  • 2.
    In the formof spinner’s package Warp preparation Weft preparation Winding (cone, Cheese) Winding (Cop,pirn) Warping(pre beam,warp) Weaving Sizing (weavers beam) Drafting, Drawing,Denting, Weaving
  • 3.
    Flow chart ofprocessing
  • 4.
    Textile Chemical Processingfor the Fibres (Preparatory Operations) • The fabric collected from various weaving setups, can not be used directly for manufacturing various textile products. • There are number of impurities present in the fabric such as dust, dirt, oil stains, oil and waxes, starches or other sizing materials, seed particles, and natural coloring materials. These impurities can be classified as. I. Natural Impurities & II. Added Impurities
  • 5.
    Objectives of pre treatment Themain objectives of preparatory treatments of textile materials are, 1. To remove all the impurities, both naturals and those added during production that may interfere in subsequent dyeing or finishing process. 2. Improve the ability of the fibers to absorb water, dyes solutions and chemicals. 3. Impart proper brightness or whiteness to fabrics according to need, especially when brilliant or pastel shades are desired.
  • 6.
    Preparatory process Important PreparatorySteps for Cotton Fabric • Singeing • Desizing • Scouring • Bleaching • Mercerizing
  • 7.
    SINGEING • Singeing isa process of burning off protruding fibers from the surface of the yarn of the fabric in order to improve the lustre and Smoothness of the material. Types of singeing: • Hot plate singeing machine • Roller singeing machine • Gas-singeing machine
  • 8.
    DESIZING • The removalof added size material in process of sizing is known as desizing. Methods Of Desizing Hydrolic Oxidative Novel Rot steep Chlorine Solvent Enzymatic Chlorite Desizing 2000 Acid steep Bromite LT plasma Treatment
  • 9.
    SCOURING • The oilsand fatty acids of inorganic compounds form a layer on fabric which are hydrophobic and affect the absorbency of cloth. the process by which the water resistant layer is removed is known as Scouring. • Scouring Processes for cotton:- 1.The lime soda process 2.Caustic-soda boil 3.Treatment with soap and soda ash 4.Enzyme scouring
  • 10.
    BLEACHING • Bleaching isa process by which the natural colouring matter and any other colouring matter is removed from natural fibers or process discoloration from man-made fibers. • Classification of Bleaching Agents: 1. Oxidizing bleaching agents Cl₂, H₂O₂, Na₂O₂, K₂S₂O₈, HOCl, KMnO₄, O₃ 2. Reducing bleaching agents So₂, Na₂SO₃, Na₂S₂O₄, H₂SO₃, NaHSO₃
  • 11.
    Bleaching Reciepe 1. Desizing 0.3%Desize soln 0.4% Soap soln 2. Hot wash 4.5% NaoH boiling H₂O₂ 1% Stabilizer 0.25% 3. Bleaching Bleaching 20gpl Cold wash- 2 rounds HCl 1% Soda 0.5%
  • 12.
    Mercerization • Mercerization processwas invented by John Mercer. • In the Mercerization process, cotton fabric or yarn is treated with a cold concentrated solution of sodium hydroxide for one minute or less. In this process cotton fibers swell, untwist and their bean shaped cross section changes into a round form Mercerization improves the following properties of the cotton fabric. 1. Strength would be increased to 15-25%. 2. Enhanced luster. 3. Greater affinity to water, dyes and other chemical finishes. 4. Shrinkage control in both the direction of the fabric.
  • 13.
    Dyeing • Dyeing isby far the most widely used means of applying color to textiles. • Dyes, by definition, are soluble in the medium in which they are applied, and the medium is almost always water. Immerse Textile in Dye-bath Apply Heat, Time, Chemicals to Drive Dye into Textiles Rinse to Remove Surface Dye All Dye is in Bath Most of the Dye Now on Textiles Unfixed Surface Dye Removed
  • 14.
  • 15.
    Dyeing Can BeDone at Different Stages: • Fiber Stage • Yarn Stage • Fabric Stage • Garment Stage
  • 16.
    • General Principlesand Terms Met in Dyeing 1) Dye Exhaustion – This describes how much of the total dye applied resides on the fiber rather than in the dye liquor. 2) Equilibrium – This is when the final or equilibrium degree of exhaustion has been reached. If the dyeing is allowed to proceed under the same conditions for a longer time, the shade of the dyed goods will remain the same. 3) Levelness and Leveling Power - levelness depends on: » Liquor ratio – The leveling power increase as the LR increases as there is more dye in the bath » Substantivity – Low substantivity favors leveling » Temperature – Higher temperature give more level dyeing » Time – Longer times give more level dyeing
  • 17.
    Piece Winch (or beck)Dyeing • Fabric pieces are sewn end to end and this rope-like form is dyed in a relaxed state. • It is most widely used on knitted, woolen and worsted fabrics.
  • 18.
    Piece Jig Dyeing •Fabric is treated in open width and is passed through the dye bath rather than immersed in to a dye bath and this is repeated. • There is a degree of tension on the fabric and is therefore used on woven fabrics and not knits.
  • 19.
    Piece Pad Dyeing •The dye solution is applied by means of a padder and the fabric in open form is run through an open vat. • The fabric is subject to tension, so only selected fabrics can be dyed. • Advantages: System can handle thousands of yards and dye can be added automatically to provide consistency of dye color
  • 20.
    Reactive Dyeing The reactivedyes are water-soluble anionic dyes, which react with hydroxyl groups of cellulose to become covalently bonded to the fiber. • The chemical reaction between a reactive dye and a cellulose fiber takes place in the presence of a base and can be summarized as follows • Offers bright colors with very good colorfastness, (particularly good washfastness and excellent light fastness). • Susceptible to damage from chlorine bleaches
  • 21.
    VAT The Vat dyesare insoluble organic compounds that are not substantive to cellulose. The following steps are involved in dyeing: 1) Reduction (Vatting): Prior to dyeing they are converted to their soluble form (leuco soluble vat dye) by means of reduction in the presence of a strong base. 2) Dyeing: In this soluble form, they are substantive to cellulosic fibers, and can be applied to them. 3) Oxidation: Once inside the fibers, uniformly distributed, the Vat dyes are then oxidized and converted back to their original insoluble form. 4) Soaping: to achieve a stable shade.
  • 22.
    VAT • The softwater throughout the dyeing stage is a must with Vat dyes, since the soluble Leuco salts form insoluble salts with Calcium or Magnesium ions as well as with transition metals. • A wide choice of colors with good to excellent colorfastness is available, although their lightfastness may be somewhat inferior.
  • 23.
    Direct • Direct dyesare soluble anionic dyes. • The Direct dyes are so called because they were the first dyes to dye cellulosic fibers directly without the need for a pre- treatment of the fibers with a mordant. • The mechanisms by which direct dyes become attached to cellulose is assumed to be through the formation of a large number of weak attractions between the dye and the fiber. • Direct dyes exhibit relatively good colorfastness to sunlight, and some are considered to have excellent lightfastness. However colorfastness to washing is poor and therefore not appropriate for frequently washed apparel. • The problem of poor washfastness can be improved to some degree by formaldehyde after treatment. Direct
  • 24.
  • 25.
    SHRINKAGE CONTROL FINISHES • Areduction in the length or width of a fibre, yarn or fabric is known as shrinkage. Growth occurs when a fabric increases in dimension. It is essential to know the shrinkage of the fabrics in both the directions ( Warp wise and weft wise) to determine construction and design of garment • Causes of Shrinkage • Intermolecular structure of fibres • Yarn twist • Fabric construction (Yarns / inch) • Weave / knit structure
  • 26.
    Compressive Shrinkage (Sanforization) • InCompressive Shrinkage process, the fabric is dampened and is placed on a machine equipped with a continuous thick woolen felt blanket. The blanket travels around a smaller roller carrying the • fabric with it as it • stretches around • the curve of the roller.
  • 27.
    ETP It is aprocess design for treating the industrial waste water for its reuse or safe disposal to the environment. • Influent: Untreated industrial waste water. • Effluent: Treated industrial waste water. • Sludge: Solid part separated from waste water by ETP. Treatment levels: 1. Prelimnary 2. Primary 3. Secondary 4. Tertiary (or advanced) • Treatment mechanisms: 1. Physical 2. Chemical 3. Biological
  • 28.
    Conclusion • I learntall the techniques and process of textile processing. • This Internship help in knowing the various machine used for processing. • Due to secrecy act, all the data on recipe, method & activities has not been supplied & hence the data given regarding to this do not resemblance to the actual data. • The whole process is not possible to bind in such a small frame as this report, hence our effort spenton summarizing, not describing them
  • 29.
    References • Textile chemicalprocessing, Students Handbook Central Board Of Secondary Education Shiksha Kendra, 2, Community Centre, Preet Vihar, Delhi-110301 • Wet Processing Technology-Internship Report https://www.scribd.com/document/294278091/Wet-Processing- Technology-Internship-Report-pdf accessed on 28th, Jan 2018 • Textile Internship Report - arvind denim division https://www.scribd.com/doc/104909847/2012-Textile-Internship- Report-arvind-denim-devision • Internship report on dyeing http://www.assignmentpoint.com/science/textile/internship-report- on-dyeing.html Accessed on 29th, Jan 2018 • Srini Venkatraman, 2006 Bureau Veritas file:///C:/Users/user/Downloads/dyingprintingfinishing- 100504132149-phpapp01.pdf Accessed on 30/01/2018
  • 30.