HDPE AND OTHER TECHNICAL FIBERS ,THEIR PROPERTIES APPLICATIONS , USES

1. Presentations
@IIT-D
BY
VIVEK YADAV
9457631264

2. A Presentation on
Printing of Acrylic Fabric
Submitted by;
Vivek Yadav
Submitted to
Pro. Kushal Sen

3. Brief introduction; Acrylic fibre
BETTER OPTION OF WOOL?
• Warm and dry hand feel like wool.
• about 30% bulkier than wool.
• 20% greater insulating power than
wool.
• Density is 1.17 g/cc
• M.R= 1.5-2% at 65% RH and 70°F
• Tenacity
5 gpd in dry state
4-8 gpd in wet state.
• Breaking elongation =15% ( both
states)
• Elastic recovery = 85% after 4%
extension

4. Basic structure of PAN
• Containing at least 85% acrylonitrile monomer
Problem regarding typical polymer?
• Polyacrylonitrile homopolymer (PAN) degrades before melting,
• has very compact structure,
• Not have dye sites .
Solution ?
At least one co monomer (methyl acrylate , methylmethacrylate or vinyl acetate ( 6-10 wt%).
• Enhance the solubility of the polymer in spinning solvents,
• Modify the fibre morphology and improve the rate of diffusion of dyes into the fibre.

5. Dye-able PAN
PROBLEM ?
Does not accept dyes readily unless special dye sites have been introduced.
SOLUTION?
Way to introduce dyesites is to copolymerize acrylonitrile with acidic or basic co-monomer.
• Ionic co-monomers -Sodium-p-styrene sulphonate, sodium methallyl- sulphonate or sodium 2-
methyl-2-acrylamido-propane sulphonate are added as comonomers
AMOUNT – No. of sulphonate and sulphate sites for cationic dyes should be around 30-50 meqkg-1.

6. Printing of acrylic
Acrylic can be print by all three methods
• Direct style
• Discharge style
• Resist style
Pretreatment ?
Combined desizing and scouring ;
• A non‐ionic detergent ,why ? , anionic dyes sites not favorable for cationic
auxiliaries
• Scouring with weakly alkaline solutions of ammonia or sodium pyrophosphate
(Na3HP207)
Bleaching-Possible with sodium chlorite (NaClO2)
Stabilizers that control chlorine dioxide emission - Borax Or Polyphosphates .
Corrosion inhibitor- sodium nitrate when using steel equipment.
Anti-chlor treatment -sodium bisulphate or thiosulphate

7. Basics about dyes used in printing
Two kinds of Cationic dyes-
Classical cationic dyes (cationic nitrogen atom is an essential part of the colour-
donating chromophore)
• sensitive to alkali
Modified cationic dyes (The newer dyes use azo, anthraquinone and phthalocyanine
structures with the cationic nitrogen in a side-chain)
• The colour of these dyes is therefore not so sensitive to alkali, but fixation will only occur
under acidic conditions
Classical Modified

8. Direct style of printing
Basic recipe
Basic dye 30–50 g
Thiodiethyleneglycol 3 g
Acetic acid (30%) 30 g
Hot water x g
Thickener 500–600 g (carboxymethylcellulose)
Citric acid/ammonium sulphate 5 g ( non volatile acid to maintain acidic during drying&fixation)
Fixation accelerator 10–20 g
Total 1000 g
Fixation-
Saturated steam
Time= 20–30 min
Pressure=at 0.1–0.2 mpa (14–28 lbf in–2) pressure in a star steamer.
For continuous-filament
Temperature (108–110 °c),
Pressure-0.14–0.15 mpa (16–21 lbf in–2),
Cold water rinsing and soaping at 50 °C, then at 70 °C with 2 g l–1 anionic detergent, are required to ensure good
fastness to rubbing and brilliance of hue.

9. Transfer printing ?
Possible ? Yes!
Desperse dye? Yes ,why not ….but ……
Print lacks intensity and light fastness also
SO WHAT ?
• Cationic dyes ? complicated , because , ionic
group will cause poor sublimation.
• Modified basic dyes to provide a sublimation
transfer system for printing acrylic fibres.
• Basic triarylmethane (carbinol form) dyes can
be volatilised from alkaline ink layers.
• The dye interacts with sulphonate groups in
the fibre to regenerate the coloured ionic form
of the dye .

10. Discharge style of printing
The Colored Ground - Dischargeable basic dyes
(basically having azo chromophores)
Illuminating colours – Non-dischargeable basic dyes.
The discharging agent - Sulphoxylate Or Tin Chloride
Mechanism-
1. Sulphoxylate -white discharge,
Too powerful for the basic dyes employed as
illuminating colours.
2 .Tin chloride- For all kinds of discharge

11. Basic recipe
Colour discharge
Basic dye x g
Water 200 g
Locust bean gum ether (10%) 400 g (thickener )
Fixation accelerator (normally organic
compounds containing nitro groups) 20 g
Tin(II) chloride (1:1) 100–180 g ( discharging agent)
Tartaric acid or citric acid 10 g
Potassium thiocyanate 0–50 g( swelling agent)
Total 1000 g
After treatment-
steamed for 20
minute
Pressure = 20–40
kPa (3–6 lbf in–2)
prints are rinsed in
cold water
treated for 20 min
1 ml per litre
NH3(25%) &1 gm/ltr
sodium
hydrosulphite.
further rinse at 40 °C
and soaping in a fresh
bath at 60–70 °C.

12. Acrylic blend dyeing
Acrylic / cellulose blends
It can be printed using Desperse and Reactive
dyes
The printing paste may contains:
Desperse – 50
Reactive –50
Wetting agent-5
Sodium alginate 6% - 500
Urea-100
Sodium bi carbonate( just before printing )-20
part
Points to be noted
• Desperse dye should be compatible to mild
alkali.
• Otherwise soda ash has to be eliminated from
the paste and reactive dye to be developed in
separate pad batch process.
Printing
Drying at 105
degree centigrade
Steamed for 30
min ,
pressure=0.5
kg/sqr cm
Washed & soaped
at 60 degree
centi, 5 min
Wash with hot
and cold water
sequentially

13. Printing of acrylic and wool-
Basic dyes are used for both the components
Printing paste contains following recipe
Cationic dye Xgm
Thiodiethylene glycol 30gm
Glacial acetic acid 10gm
Phenol 10gm
Sodium chlorate 5g
Water at 70°C -
Thickening -
Total: 1Kg
After printing fabric my be steamed at 103°C
in a star ager for 30 minutes followed by cold
rinse, hot rinse, soaping at 60°C for 20 min.
Finally hot rinse and cold rinse.
Printing of acrylic nylon blends –
Acrylic/polyamide blended may be printed
with cationic dyes. The print paste may
contain:
Cationic dye Xgm
Thiodiethylene glycol 30gm
Resorcinol 15gm
Glacial acetic acid 10gm
Tartaric acid 5gm
Sodium chlorate 5gm
Dissolving salt b 20gm
Water at 70°C
Thickening
Total: 1Kg
After printing fabric my be steamed at 103°C
in a star ager for 30 minutes followed by cold
rinse, hot rinse, soaping at 60°C for 20 min.
Finally hot rinse and cold rinse.

14. Recent development in acrylic printing
• Digital Printing of Acrylic Fabric with Cationic Dyes Using Conventional
Inkjet Printer are available now .
• Printing of acrylic from acid , reactive , and direct dyes are possible.
(A known weight of acrylic fabric is pretreated with hydroxylamine hydrochloride (10 g/l) using aqueous
solutions of ammonium acetate (20 g/l) at a liquor-to-goods ratio of 50:1 at 85°C for 1 hour.)
• Different Surface modification methods for improving dyeability of acrylic
fabric using different natural biopolymer.
Area to focus …..
• Wide range of shades with conventional dyes , because other dyes does not
provide enough tinctorial value .
• Appropriate and high productivity digital printing with sharp image on
piled and bulky substrate of acrylic .

15. References
• R.S. Prayag ,Technology of textile printing ,
• W C Miles, Textile printing , Edited by Leslie,Formerly Lecturer in Textile
Chemistry, Department of Textiles, University of Manchester Institute of Science
and Technology, Manchester, UK, 2003 ,Society of Dyers and Colourists.
• Reda M. El-Shishtawy, S.H. Nassar, Nahed S.E. Ahmed ,Anionic colouration of
acrylic fibre. Part II: Printing with reactive,acid and direct dyes,Textile Research
Division, National Research Centre, El-Behouth St. Dokki, Cairo, PO 12622, Egypt
Received 16 August 2005;
• Sajjad Fashandi Digital Printing of Acrylic Fabric with Cationic Dyes Using
Conventional Inkjet Printer,Department of Textile Engineering, Amirkabir
University of Technology (Tehran Polytechnic), Tehran 15914, Iran ,Received 15
November 2015; revised 24 May 2016; accepted 27 May 2016
• M.M., Allam, O.G., El Gabry, L.K. and Helmy ,Surface Modification Methods for
Improving Dyeability of Acrylic Fabric Using Natural Biopolymer, H.M. Textile
Research Division, National Research Centre, Dokki, Cairo, Egypt,2013