PREPARATORY PROCESSES R.B.CHAVAN Dept. of Textile Technology Indian Institute of Technology Hauz-Khas, New Delhi 110016
CLASSIFICATION OF TEXTILE FIBRES <ul><li>Minor Classifiction </li></ul><ul><ul><li>Natural   Synthetic   Regenerated  </li...
CLASSIFICATION OF TEXTILE FIBRES <ul><li>Major </li></ul><ul><li>Basis  </li></ul><ul><li>Textile fibre product identifica...
Natural fibres <ul><li>Cellulosic fibres </li></ul><ul><li>Seed hairs: Cotton, Kapok </li></ul><ul><li>Bast fibres: Flax, ...
Natural Protein fibres <ul><li>Animal hair fibres </li></ul><ul><li>Wool (Sheep) </li></ul><ul><li>Speciality hair fibres:...
Regenerated natural fibres <ul><li>Rayon  </li></ul><ul><li>Cuprammonium </li></ul><ul><li>Viscose: Regular, high tenacity...
Synthetic fibres <ul><li>Condensation polymers </li></ul><ul><li>Polyamide </li></ul><ul><li>Nylon 6, 66, 11 </li></ul><ul...
Synthetic fibres <ul><li>Elastomers </li></ul><ul><li>Spandex </li></ul><ul><li>Synthetic Rubber </li></ul><ul><li>Lastril...
Chemical processing <ul><li>Give value addition  </li></ul><ul><li>Can be carried out in  </li></ul><ul><li>Fibre </li></u...
Chemical processing operations <ul><li>Preparatory </li></ul><ul><li>Dyeing  </li></ul><ul><li>Printing </li></ul><ul><li>...
Preparatory Processes  <ul><li>Purpose </li></ul><ul><li>To remove </li></ul><ul><li>Natural and added impurities </li></u...
Fabric manufacturing   <ul><li>Fibre    Yarn     Fabric   Fabric for sale  </li></ul><ul><li>Spinning:   Fibre to yarn ...
Operations before Preparatory Processes <ul><li>Weaving: Conversion of yarn to fabric </li></ul><ul><li>Machine used: Loom...
Grey fabric inspection  <ul><li>Major fabric defects </li></ul><ul><li>Oil stains: formed accidentally during weaving and ...
Fabric faults Stains   Thick place  Missing end or pick  Hole
Grey fabric inspection machines Individual piece inspection (Mannual)
Grey fabric inspection machine (Continuous length  (Manual)
Grey fabric inspection machine
fabric inspection machine  Digital cameras, computerized
Stamping   Lot card <ul><li>Lot Number  </li></ul><ul><li>Placing the code mark in the form of lot No. with marking ink  <...
Lot card <ul><li>Lot No. </li></ul><ul><li>Yarn count  </li></ul><ul><li>Fabric construction details such as </li></ul><ul...
Mechanical operations <ul><li>Brushing </li></ul><ul><li>Shearing/Cropping </li></ul><ul><li>Singeing  </li></ul>
Brushing   <ul><li>Purpose </li></ul><ul><li>To remove short loose threads from fabric surface </li></ul><ul><li>Operation...
Shearing/Cropping <ul><li>Purpose </li></ul><ul><li>To cut the loose threads attached to the fabric surface </li></ul><ul>...
Four cutter shearing machine
Singeing  <ul><li>Purpose </li></ul><ul><li>To burn the protruding fibres present on the fabric surface. </li></ul><ul><li...
Gas singeing machine
Composition of cotton <ul><li>Natural impurities </li></ul>Constituent % Cellulose 88 Oils and Waxes 0.5 Pectins 0.7 Prote...
Fats and Waxes <ul><li>These are  </li></ul><ul><li>Readily saponifiable triglycerides of fatty acids </li></ul><ul><li>Wa...
Fats and Waxes <ul><li>Fatty acids </li></ul><ul><li>Stearic acid </li></ul><ul><li>Palmitic acid </li></ul><ul><li>Oleic ...
Reactions <ul><li>Fat </li></ul><ul><li>3 C17H35COOH +  </li></ul>OH-CH2 OH-CH OH-CH2 = (C17H35COO) 3  C3H5 + 3H2O Wax C17...
Pectins  <ul><li>Derivatives of pectic acid  </li></ul><ul><li>Polymer of high molecular weight </li></ul><ul><li>Composed...
Proteins <ul><li>Nitrogenous compounds </li></ul><ul><li>Present in primary wall and Lumen </li></ul><ul><li>Some of the a...
Colouring matter  <ul><li>Colour pigments present are </li></ul><ul><li>3,5,7,2’, 4’ Penta hydroxy flavone (Morrin) </li><...
Mineral Matter <ul><li>Depends on soil composition </li></ul><ul><li>Can be determined by ash analysis </li></ul>Potassium...
Upcoming SlideShare
Loading in...5
×

Lecture 1 tt 241 introduction

1,743

Published on

Published in: Education, Business, Lifestyle
0 Comments
4 Likes
Statistics
Notes
  • Be the first to comment

No Downloads
Views
Total Views
1,743
On Slideshare
0
From Embeds
0
Number of Embeds
2
Actions
Shares
0
Downloads
0
Comments
0
Likes
4
Embeds 0
No embeds

No notes for slide

Lecture 1 tt 241 introduction

  1. 1. PREPARATORY PROCESSES R.B.CHAVAN Dept. of Textile Technology Indian Institute of Technology Hauz-Khas, New Delhi 110016
  2. 2. CLASSIFICATION OF TEXTILE FIBRES <ul><li>Minor Classifiction </li></ul><ul><ul><li>Natural Synthetic Regenerated </li></ul></ul><ul><ul><li>Vegetable Animal </li></ul></ul><ul><ul><li>Polyester Viscose Rayon </li></ul></ul><ul><ul><li>Cotton Silk Nylon </li></ul></ul><ul><ul><li>Jute Wool Acrylic </li></ul></ul>
  3. 3. CLASSIFICATION OF TEXTILE FIBRES <ul><li>Major </li></ul><ul><li>Basis </li></ul><ul><li>Textile fibre product identification act 1960 </li></ul><ul><li>Considerations: </li></ul><ul><li>Principal origin of fibre (Natural or man-made) </li></ul><ul><li>Generic term (Seed, hair, rayon) </li></ul><ul><li>Common names (cotton, viscose, nylon etc.) </li></ul>
  4. 4. Natural fibres <ul><li>Cellulosic fibres </li></ul><ul><li>Seed hairs: Cotton, Kapok </li></ul><ul><li>Bast fibres: Flax, Ramie, Hemp, Jute, Sunn, Kenaf </li></ul><ul><li>Leaf fibres: Abaca, Pineapple, Sisal (Agave), Palm </li></ul><ul><li>Fruit: Coir </li></ul><ul><li>Mineral: Asbestos </li></ul>
  5. 5. Natural Protein fibres <ul><li>Animal hair fibres </li></ul><ul><li>Wool (Sheep) </li></ul><ul><li>Speciality hair fibres: Alpaca, Camel, Cashmere, Mohair (Angora Goat), </li></ul><ul><li>Fur fibres: Mink, Muskrat, Rabbit </li></ul><ul><li>Animal Secretion </li></ul><ul><li>Silk fibre: Mulberry, Tussar, Moga, Erie </li></ul><ul><li>Spider silk </li></ul>
  6. 6. Regenerated natural fibres <ul><li>Rayon </li></ul><ul><li>Cuprammonium </li></ul><ul><li>Viscose: Regular, high tenacity, high wet modulus, hollow fibres, polynosic, lyocell </li></ul><ul><li>Acetate: Secondary acetate, Tri acetate </li></ul><ul><li>Regenerated Protein: Casein, Zein, Peanut, Soyabean </li></ul><ul><li>Miscellaneous: alginate </li></ul>
  7. 7. Synthetic fibres <ul><li>Condensation polymers </li></ul><ul><li>Polyamide </li></ul><ul><li>Nylon 6, 66, 11 </li></ul><ul><li>Aramide : Quiana, Kevlar, Nomex </li></ul><ul><li>Polyester </li></ul><ul><li>Aromatic: Polyethylene terephthalate (PET) </li></ul><ul><li>Aliphatic Poly lactic acid (PLA) </li></ul><ul><li>Addition polymers </li></ul><ul><li>Acrylic, modacrylic </li></ul><ul><li>Olehene fibres: Polyethylene, polypropelene </li></ul><ul><li>Saran </li></ul><ul><li>Vinal </li></ul><ul><li>Vinyon </li></ul>
  8. 8. Synthetic fibres <ul><li>Elastomers </li></ul><ul><li>Spandex </li></ul><ul><li>Synthetic Rubber </li></ul><ul><li>Lastrile </li></ul><ul><li>Man-made (Mineral) </li></ul><ul><li>Glass </li></ul><ul><li>Metallic </li></ul>
  9. 9. Chemical processing <ul><li>Give value addition </li></ul><ul><li>Can be carried out in </li></ul><ul><li>Fibre </li></ul><ul><li>Yarn </li></ul><ul><li>Fabric </li></ul><ul><li>Garment or other ready made forms. </li></ul>
  10. 10. Chemical processing operations <ul><li>Preparatory </li></ul><ul><li>Dyeing </li></ul><ul><li>Printing </li></ul><ul><li>Finishing </li></ul>
  11. 11. Preparatory Processes <ul><li>Purpose </li></ul><ul><li>To remove </li></ul><ul><li>Natural and added impurities </li></ul><ul><li>To improve the appearance of fabric </li></ul><ul><li>To impart certain desirable properties </li></ul><ul><li>To make it suitable for subsequent processes like dyeing, printing finishing </li></ul>
  12. 12. Fabric manufacturing <ul><li>Fibre  Yarn  Fabric  Fabric for sale </li></ul><ul><li>Spinning: Fibre to yarn </li></ul><ul><li>Weaving: Yarn to fabric by interlacement of yarn in length direction and width direction </li></ul><ul><li>Length direction yarn Warp </li></ul><ul><li>Weft direction yarn: Weft </li></ul><ul><li>Grey fabric </li></ul><ul><li>for sale or </li></ul><ul><li>chemiccal processing </li></ul>
  13. 13. Operations before Preparatory Processes <ul><li>Weaving: Conversion of yarn to fabric </li></ul><ul><li>Machine used: Loom </li></ul><ul><li>Fabric known as </li></ul><ul><li>Loom state fabric or </li></ul><ul><li>Grey fabric </li></ul><ul><li>Grey fabric length: 80 </li></ul>
  14. 14. Grey fabric inspection <ul><li>Major fabric defects </li></ul><ul><li>Oil stains: formed accidentally during weaving and handling </li></ul><ul><li>Holes </li></ul><ul><li>Thick places due to yarn defect </li></ul><ul><li>Warp or weft thread breaks </li></ul><ul><li>Long thread of fabric surface </li></ul><ul><li>others </li></ul>Chemical processing step
  15. 15. Fabric faults Stains Thick place Missing end or pick Hole
  16. 16. Grey fabric inspection machines Individual piece inspection (Mannual)
  17. 17. Grey fabric inspection machine (Continuous length (Manual)
  18. 18. Grey fabric inspection machine
  19. 19. fabric inspection machine Digital cameras, computerized
  20. 20. Stamping Lot card <ul><li>Lot Number </li></ul><ul><li>Placing the code mark in the form of lot No. with marking ink </li></ul><ul><li>Ink should withstand chemical processing operations </li></ul><ul><li>Lot No. mark helps to identify the fabric lot at any stage of processing. </li></ul><ul><li>Stitching of individual non-defective pieces </li></ul>
  21. 21. Lot card <ul><li>Lot No. </li></ul><ul><li>Yarn count </li></ul><ul><li>Fabric construction details such as </li></ul><ul><li>Ends and Picks per inch or per cm. </li></ul><ul><li>Fabric weight g/sq.m (gsm) </li></ul><ul><li>Processing sequence </li></ul><ul><li>Date and time on which the lot has been received </li></ul><ul><li>Date and time of subjecting the lot to different processing sequence along with signature of supervisor </li></ul><ul><li>The information helps in knowing the status of lot at any time and analysis of processing problems if there are any. </li></ul>
  22. 22. Mechanical operations <ul><li>Brushing </li></ul><ul><li>Shearing/Cropping </li></ul><ul><li>Singeing </li></ul>
  23. 23. Brushing <ul><li>Purpose </li></ul><ul><li>To remove short loose threads from fabric surface </li></ul><ul><li>Operation </li></ul><ul><li>Fabric moves in contact with Cylinders (2-4) covered with fine bristles (Brush Roller). </li></ul><ul><li>The loose threads are picked up by the brush rollers. </li></ul><ul><li>Removed by vacuum. </li></ul><ul><li>In this operation only loose threads are removed </li></ul><ul><li>Threads attached to the fabric surface removed by shearing/cropping operation. </li></ul>
  24. 24. Shearing/Cropping <ul><li>Purpose </li></ul><ul><li>To cut the loose threads attached to the fabric surface </li></ul><ul><li>Achieved by raising the loose thread with the help of brush roller and cutting it close to the fabric surface with the help of spiral blades. </li></ul>
  25. 25. Four cutter shearing machine
  26. 26. Singeing <ul><li>Purpose </li></ul><ul><li>To burn the protruding fibres present on the fabric surface. </li></ul><ul><li>Impart smooth appearance to the fabric. </li></ul><ul><li>Improve the appearnce of dyed and printed fabric. </li></ul><ul><li>Principle </li></ul><ul><li>Burning of protruding fibres by means of gas flame. </li></ul><ul><li>Passage of fabric at high speed (180 m/min) </li></ul><ul><li>Contact time with flame: Fraction of seconds </li></ul><ul><li>Fabric is quenched immediately when it comes out of machine </li></ul>
  27. 27. Gas singeing machine
  28. 28. Composition of cotton <ul><li>Natural impurities </li></ul>Constituent % Cellulose 88 Oils and Waxes 0.5 Pectins 0.7 Proteins 1.1 Colouring matter 0.5 Mineral Matter 1.0 Moisture 8.0
  29. 29. Fats and Waxes <ul><li>These are </li></ul><ul><li>Readily saponifiable triglycerides of fatty acids </li></ul><ul><li>Waxes which are saponified with difficulty </li></ul><ul><li>Free fatty acids </li></ul><ul><li>Traces of soaps </li></ul><ul><li>Free fatty acids and fatty alcohols identified in cotton are </li></ul>
  30. 30. Fats and Waxes <ul><li>Fatty acids </li></ul><ul><li>Stearic acid </li></ul><ul><li>Palmitic acid </li></ul><ul><li>Oleic acid </li></ul><ul><li>Fatty alcohols </li></ul><ul><li>Gossipyl alcohol (C30H61OH) </li></ul><ul><li>Ceryl alcohol (C26H53OH) </li></ul><ul><li>Montanyl alcohol (C28H57OH) </li></ul>
  31. 31. Reactions <ul><li>Fat </li></ul><ul><li>3 C17H35COOH + </li></ul>OH-CH2 OH-CH OH-CH2 = (C17H35COO) 3 C3H5 + 3H2O Wax C17H35COOH + OHC28H57 = C17H35COOC28H57
  32. 32. Pectins <ul><li>Derivatives of pectic acid </li></ul><ul><li>Polymer of high molecular weight </li></ul><ul><li>Composed of Galactouronic acid </li></ul>Some COOH groups are present as Ca and Mg salts Free acid and Ca and Mg salts are insoluble in water
  33. 33. Proteins <ul><li>Nitrogenous compounds </li></ul><ul><li>Present in primary wall and Lumen </li></ul><ul><li>Some of the amino acids identified are </li></ul><ul><li>Leucine </li></ul><ul><li>Valine </li></ul><ul><li>Proline, </li></ul><ul><li>Alanine etc. </li></ul><ul><li>Yellowish (Creamish) colour of cotton is related to Proteins and </li></ul><ul><li>Colouring matter </li></ul>
  34. 34. Colouring matter <ul><li>Colour pigments present are </li></ul><ul><li>3,5,7,2’, 4’ Penta hydroxy flavone (Morrin) </li></ul><ul><li>3,5,7,8,3’,4’ Hexa hydroxy flavone (Gossypetine) </li></ul>
  35. 35. Mineral Matter <ul><li>Depends on soil composition </li></ul><ul><li>Can be determined by ash analysis </li></ul>Potassium carbonate 44.8 Potassium chloride 9.9 Potassium sulphate 9.3 Calcium sulphate 9.0 Calcium carbonte 10.3 Magnesium sulphate 8.4 Ferric oxide 3.0 Aluminium oxide 5.0

×