Stock Dyeing

Textile Dyeing process

1. Dyeing & Printing Presentation on Stock Dyeing Submitted to : Ms. Ettishri Rajput Submitted by : Ajay Gayakwar Bittu Singh Radhe Kumar Shubham Singh

2. Stock Dyeing Dyeing a staple fibre before it is spun 500-3000 pounds of fibre are dyed at a time Methods : Old – removing packed fiber from bales packing the stock in large vats circulating dye liquor through the mass of fiber at elevated temperatures New – B ale Dyeing – applicable to Wool & all types of man-made fibres Splitting the bale covering on all six sides placing the entire bale in machine along with the covering & straps forcing dye liquor through the bale - saves time and costs

3. Stock Dyeing Overall even colour is obtained Stock-dyed fiber doesn’t spins as readily as undyed fiber – loses some of its flexibility – lubricants added in final rinsing overcome most of this problem Woolens – often stock dyed Expression “dyed in the wool” – attributes the quality of thoroughness Uses – Oxford suitings , Tweed homespuns or Heather effect materials in which delicate shadings of colours are produced by combining fibres of various colours Tweed fabric Staple fiber packed onto a carrier being placed into a vat

4. Machinery & Technique Types : Conical pan machine – fibre packed into a removable fibre carrier - fibre carrier – located on a central spigot in the base of the vessel - liquor circulation provided by an external pump - pipework allows liquor to be circulated either from the base or the top

5. Machinery & Technique Pear shape machine – removable perforated base plate through which liquor is circulated via an impeller - fibre is loaded directly – a perforated plate is positioned on top - liquor circulation packs fibre between the two plates - unloading – plates removed by cranes & fibre manually Radial flow – a fibre carrier equipped with a central perforated column - column – liquor flows across the pack to walls of the carrier

6. Machinery & Technique Loose fibre – usually packed manually – capacity varies between 200-300 kgs Working volume equivalent – 7 to 10 litres per kg fibre Machines – low packing density – liquor circulates freely through fibre ar modest pressure – minimizes mechanical damage to fibre Bath – heated by closed steam coils in the base of the machine – temperature may be controlled by a steam valve Electro/Pneumatic programs or Logic controllers – regulate time/temperature or control direction of liquor circulation Liquor ratio – varies between 1:4 to 1:12 – depends on type of machine/ fibre

7. Latest Modifications Earlier – machines made of wood – dyes and chemicals were retained by them affecting successive processes Now – machines made of stainless steel Automation : Operations such as machine filling, rise of temperature, circulation of liquor or material, holding time, cooling time, draining C ontrolled using sensors, actuated valves, sequence controller, micro-processor Benefits of automation : R educed waste of materials, reduced dead time, improved shades, exact record of consumption

8. Advantages Excellent penetration of dye in the fabric & evenness of colour throughout Effects such as Heather effect may be obtained Dye penetrates core of the fibre – resists rubbing – high colour fastness Disadvantages Most costly method for dyeing Low yield 10-15% of dyed fabrics are wasted through manufacturing steps Not used for Worsted yarns – combing process removes short fibres – leads to waste of resources

9. References Shenai V. A. Technology of Dyeing , Volume VI. Pages 83-90. Bombay. 1980. Corbman B. P. Textiles : Fiber to Fabric . Pages 212-213. Singapore. 1983. Choudhury A. K. Textile Preparation & Dyeing . Pages 407-408. Retrieved from : https://books.google.co.in/books?id=0TamObsaaPQC&pg=PA402&dq=loose+stock+dyeing+machine&hl=en&sa=X&ved=0ahUKEwj9pu24k4TPAhUIQY8KHaAzDNEQ6AEINTAA#v=onepage&q=loose%20stock%20dyeing%20machine&f=false Ministry of Environment & Energy, France . Wet Processes : Machinery & Techniques. 2000 . Retrieved from : http://ied.ineris.fr/sites/default/interactive/bref_text/breftext/anglais/bref/BREF_tex_gb54.html

10. Thank You!