lecture of textile printing

1. INTRODUCTION TO TEXTILE
MANUFACTURING
(TXT-175)
By: Nirmal Malik

2. PRINTING
• When colored patterns and designs are
applied to a finished fabric for its
decoration, it is called 'Printing'.
• In printing, the color is firmly affixed to the
fiber so that it may not be affected by
washing and friction.
• Textile printing is related to dyeing in the
sense that in both the processes color is
applied to the fabric.
• The difference lies in the fact that in dyeing,
the color is applied uniformly to the whole
fabric whereas in printing one or more
colors are applied to it in selected parts
only, and in sharply defined patterns.

3. Types of Dyes used in Printing
• For cotton printing vat and reactive dyes are generally
used.
• Silk is usually printed with acid colors.
• Wool is printed with acid or chrome dyes but before
printing it is treated with chlorine to make it more receptive
to colors.
• Manmade fibers are generally printed with disperse and
cationic dyes.

4. Methods of Printing
• For printing color on a fabric, mostly three techniques
are applied:
1. Direct Printing,
2. Discharge Printing
3. Resist Printing.

5. Direct Printing
• Direct Printing It is the most common approach to apply a
color pattern onto a fabric.
• If done on colored fabric, it is known as overprinting.
• The desired pattern is produced by pressing dye on the
fabric in a paste form.

6. Discharge Printing
• In this technique, the fabric is
dyed in piece and then it is
printed with a bleaching
agent that destroys the color
in the designated areas.
• Sometimes, the base color is
removed and other color is
printed in its place.
• The printed fabric is steamed
and then thoroughly
washed.

7. Resist Printing
• In this technique, a resist paste is fixed onto the fabric and
then it is dyed.
• The dye affects only those parts that are not covered by
the resist paste.
• After dyeing, the resist paste is removed leaving a pattern
on the background of the fabric.

8. Methods of Printing
• There are various methods of printing in which one of the
above three techniques is used
1. Block Printing
2. Roller Printing
3. Duplex Printing
4. Screen Printing
5. Transfer Printing
6. Air Brush Printing
7. Digital Printing
8. Batik Dyeing
9. Tie Dyeing
10. Flock Printing

9. Block Printing
• Block Printing designs are carved on a wooden or metal block
and the dyestuff in paste form is applied to the design on the
face of the block.
• The block is pressed down firmly by hand on the surface of the
fabric.
• Fixation is done through ironing.
• Time consuming process.
• Not for commercial use.

10. Screen Printing
• It is done either with flat or
cylindrical screens made of silk
threads, nylon, polyester, or
metal.
• The printing paste or dye is
poured on the screen and forced
through its unblocked areas onto
the fabric.
• Based on the type of the screen
used, it is known as 'Flat Screen
Printing' or 'Rotary Screen
Printing'.

11. Roller Printing
• Machine counterpart of block printing
• Engraved copper cylinders or rollers
are used in place of hand carved
blocks.
• When the rollers move, a repeat of
the design is printed on the fabric.
• The printed cloth is passed into a
drying chamber and then in a steam
chamber where the moisture and
heat sets the dye.
• High speed.
• Traditionally used for commercial
printing.

12. Duplex Printing
• Printing is done on both sides of the fabric either through
roller printing machine in two operations or a duplex
printing machine in a single operation.

13. Transfer Printing
• It involve the transfer of a design from one medium to
another.
• The most common form used is heat transfer printing in
which the design is printed initially on to a special paper,
using conventional printing machinery.
• The paper is then placed in close contact with the fabric
and heated, when the dyes sublime and transfer to the
fabric through the vapor phase.

14. Air Brush Printing
• Airbrush (Spray) Printing
In this method, the dye is
applied with a mechanized
airbrush which blows or
sprays color on the
fabric.

15. Tie Dyeing
• Firm knots are tied in the cloth before it is immersed in a dye.
• The outside portion of the immersed fabric is dyed but the color
does not penetrates the inside portions of the tied knots.
• There are various forms of Tie dyeing like Ikat Dyeing where
bundles of warp and/ or weft yarns are tie dyed prior to their
weaving.

16. Batik Dyeing
• Batik Dyeing It is a resist dyeing process.
• Designs are made with wax on a fabric which is then
immersed in a dye.
• The portion not having wax absorbs the color.

17. Digital Printing
• Digital printing In this form of
printing micro-sized droplets of
dye are placed onto the fabric
through an inkjet print head.
• The print system software
interprets the data supplied by a
cad Textile digital image file.
• The digital image file has the data
to control the droplet output so
that the image quality and color
control may be achieved.
• This is the latest development in
textile printing and is expanding
very fast.

18. Flock Printing
• Flocking is the technique of depositing many small fiber
particles, called "flock" onto a surface of a fabric to
produce design.
• Instead of dyes, an adhesive is used to affix the flocks on
the fabric.
• Then, roller printing produces design on its surface.
• Flocks of cotton, wool, rayon, nylon and acrylic are all
used for the purpose.