Chariots of knowledge: Textile printing

Textile printing

Textile printing is used to signify the production, by various means of colored patterns on designs upon all sorts of textile fiber.

Textile printing is the most important and versatile of the techniques used to add design, color, and specialty to textile fabrics. In other words, dyes and pigments are applied locally or discontinuously to produce the various designs. In fact, printing is described as ‘localized dyeing.’ The forces which operate between the dye and the fiber (on mechanical retention, hydrogen bonding, chemical reaction, electrostatic attraction etc.) are the same in dyeing and printing.

The term 'colorant' is used here because it covers both dyes and Pigments

STEPS OF PRINTING

Preparation of the fabric
Preparation of the print paste.
Printing the fabric.
Drying the printed fabric.
Fixation of the printed dye or pigment.
Afterwashing.

STYLES OF PRINTING

Percentage of rejection is lower than the discharge method

Direct style
Discharge: white and colored
Resist style
Raised style
Flock style
crimp/ crepon style
Burn out style

Difference between Resist and Discharge printing

Discharge printing	Resist Printing
Always sharp in outline, bright in appearance and give perfect and sparkling whites due to the bleaching effect on the discharging agent	Generally subdued and the colors are less bright; the outlines of the printing motifs are less sharp
Drastic chemical action is required to destroy the color	Little or no chemical action is involved to prevent fixation of color
Costs is higher and ingredients has to be selected carefully to facilitate complete destruction of color	Little or no chemical action is involved to prevent fixation of color
Cost is lower requiring less chemicals and auxiliaries	Cost is lower requiring less chemicals and auxiliaries
Applicable to those colors which can be discharged and has limitations; and also it is generally difficult to get reproducible results in all operations	Effective in all cases as almost colors are capable of being resisted
Relatively low chemical stability and fastness property of printed fabric	Printed fabric has great chemical stability and fastness properties