By: N.C. Pan, S.N. Chattopadhyay, A.K. Roy and K. Patra
Diversification is the only avenue for future of jute. All diversified products need attractive design, look and feel. For imparting attractive design and look, printing of the fabric with suitable dyes is one of the options.
Printing is the localized application of the dyestuff throughout the entire length of the fabric to get a desired design effect. For printing of jute fabric, reactive dyes may be used for their easy application on to the fabric.
Reactive dyes chemically react with the jute fibre and are attached to it by covalent bonds.
This printing technology, printing of jute fabric with reactive dyes, is ideal for small scale and cottage industries as good wash fast prints are obtained by this process.
Moreover, most of the diversified products are produced in small scale and cottage industries.
Plain weave grey jute fabric was scoured with sodium hydroxide (2%, owf) and non-ionic detergent (5 g/l) at 90-95C for 60 minutes and the material-to-liquor ratio was kept at 1:20. After scouring, the fabric was thoroughly washed with hot water and then in cold water, neutralized with acetic acid (2 ml/l) followed by usual cold washing.
Scoured jute fabric was bleached in a closed vessel for 90 minutes at 80-85C and the material-to-liquor ratio was kept at 1:20 with hydrogen peroxide (2 vol.), trisodium phosphate (5 g/l), sodium hydroxide (1 g/l), sodium silicate (10 g/l) and non-ionic detergent (2 g/l).
The pH of the bath was maintained at 10.
After bleaching, the fabric was washed thoroughly in cold water, neutralized with acetic acid (2 ml/l), washed again in cold water and finally dried.
Printing of jute fabric consists of four steps viz., preparation of stock paste, preparation of print paste, application of print paste onto the fabric and fixation of prints.
Stock paste was prepared by using thickener (sodium alginate, 50 gms/kg), urea (310 gms/kg), sodium bicarbonate (40 gms/kg) and water (600 gms/kg) with high speed stirring.
Stock paste should be free from any coagulating matter.
Print paste was prepared by using substitution type reactive dye (Amactive Orange H4R, 40 gms/kg) and stock paste (960 gms/kg) with high speed stirring.
Scoured-bleached jute fabric was printed with above print paste by screen printing technique. After printing, the fabric was dried at 80C for 5 minutes.
The fixation of prints was carried out by thermo fixation method at a temperature of 150C for 5 minutes.
After thermo fixation, cold washing, soaping, again thorough cold washing and drying was carried out.