2. PRINTING
Textile printing is the process of applying colour to
fabric in definite pattern or designs. In properly
printed fabrics the colour is bonded with the fibre, so
as to resist washing and friction.
3. STYLES OF PRINTING
There are different styles of printing, they are as follows:
DIRECT PRINTING
DISCHARGE PRINTING
RESIST PRINTING
DIRECT PRINTING:
In case of direct printing the dye is applied to specific areas of
a pretreated textile substrate, which can be white or predyed
(in light colours)
4. DISCHARGE PRINTING
It is possible to speak of discharge printing, if in the fixation
process that follows the application of the printing paste.
There is local distraction of dye applied previously. If the
etched the previously dyed area becomes white, then the
process is called white discharge.
If, on the contrary, colored pattern has to be obtained in the
etched area after the distraction of previously applied dye,
then the process is called colored discharge.
5. In this case the printing must contain a reduction resistant
dye along with the chemicals needed to destroy the previous
one. As a result the pre dyed background is destroyed
according to a pattern and the dye, which is resistant to
reduction, takes its place.
6. RESIST PRINTING
In the case of resist printing, a special printing paste is
printed on to certain area of the fabric to prevent the dye
fixation.
In the case of physical resist the material is printed with a
difficult to wet resin that inhibits the penetration of dye
applied in a second stage.
On the other hand, with a chemical resist, dye fixation is
prevented by a chemical reaction. Depending on the way the
process is carried out, one can speak of pre printing,
intermediate or over printing resist.
7. One common procedure is the wet on wet process in which
the resist paste is initially printed, then the material is over
printed with full cover screen and finally fixed and washed.
Over printing resist can be applied only if the dye, already
prevent in the previously dyed and dried fabric, is still in its
unfixed form, as in the case of developing dyes.
8. METODS OF PRINTING
There are different methods of printing, the are as follows,
Screen printing
Roller
Rotary
Transfer
Stencil
Block
Flock
9. SCREEN PRINTING
Screen printing is a printing technique where by a mesh is
used to transfer ink on to a substrate, except in areas made in
impermeable to the ink by a blocking stencil. A blade are
squeegee is moved across the screen to fill the open mesh
apertures with ink, and a reverse stroke then causes the
screen to touch the substrate momentarily along a line of
contact. This causes the ink to wet the substrate and be
pulled out the mesh.
Screen printing is also a stencil method of print making in
which a design is imposed a on a screen of polyester or other
fine mesh, with blank areas coated with an impermeable
substance.
10. Ink is forced into a mesh openings by the full blade or
squeegee and by wetting the substrate, transferred onto the
printing surface during the squeegee stroke.
The most popular mesh in general use is made of polyester.
There are special use mesh material of nylon and stainless
steal available to the screen printer there are also different
types of mesh size which will determine the outcome and
look of the finished design on the material.
11. ROLLER PRINTING
Roller printing also called cylinder printing or machine printing
on fabrics in a textile printing process patented by Thomas bell
of Scotland in 1783 in an attempt to reduce the cost of the earlier
copper plate printing. This method was used in Lancashire
fabrics mills to produce cotton dress fabric from the 1790’s, most
often reproducing small monochrome patterns charecterised by
striped motives and tiny dotted patterns called “MACHINE
GROUNDS”.
Improvements in the technology resulted in more elaborate
roller prints. In bright, rich colours form the 1820,s, turkey
redand chrome yellow are particularly popular. Roller printing
sub planted the older wood block printing on textiles in
industrialized countries until it was resurrected for textiles by
William morris in the id 19th centuary.
12.
13. ROTARY PRINTING
In basic operation, rotary screen and flat screen printing
machines are very similar. Both use the same type of in feed
device, glue trough, rotating blanket, dryer, and fixation
equipments. The process involves initially feed fabrics on to
the rubber blanket. As the screen rotates the squeegee
device pushes print paste through the designs areas of the
screen onto the fabric. As in flat bed screen printing, only
one colour can be printed by each screen. After the print
application, the process is same as flat screen printing
The screen printing process from semi continuous, to
continuous, higher production speeds are obtained.
Typically speed are from 50-120 YPM for rotary screen
printing depending upon design complexity and fabric
construction.
14. Estimates indicates that this technique control approximate
65% of printed fabric in market world wide. However, rotary
machines are used for carpet and other types of pile fabric
most knit fabric is printed by the rotary screen methods,
because it does not stress the fabric during the process.
15. TRANSFER PRINTING
Transfer printing is the term used to describe the textile and
related printing process in which the design is printed on to
a flexible non textile substrate and later transferred by a
separate process to a textile. The reasons are largely
commercial but, on occasion, technical as well and are based
on the following considerations.
1. Designs may be printed and stored on a relatively cheap
and non bulky substrate such as paper, and printed on to the
more expensive textile with rapid response to sales demand
16. 2. The production of short-run repeat orders is much easier by
transfer processes than it is by direct printing.
3. The design may be applied to the textile with relatively low
skill input and low reject rates.
4. Stock volume and storage costs are lower when designs are
held on paper rather than on printed textile.
5. Certain designs and effect can be produced only by the use of
transfers.
6. Many complex designs can be produced more easily and
accurately on paper than on textiles.
7. Most transfer-printing processes enable textile printing to be
carried out using simple, relatively inexpensive equipment
with modes space requirements, without effluent production
or any need for washing-off.
17.
18. STENCIL PRINTING
The art of stenciling on textile fabrics has been practiced
from time immemorial by the Japanese and found increasing
employment in Europe for certain classes of decorative work
on woven goods during the late 19th century
Stenciling produce an image or pattern by applying pigment
to a surface over an intermediate object with designed gaps in
it which create a pattern or image by only allowing the
pigment to reach some part of the surface the stencil is both
resulting image or pattern and the intermediate object the
contact in which the stencil is used makes clear which
meaning intended in practice the stencil usually a thin sheet
of material such as paper plastic wood or metal.
19. Stencil can be made with one or many color layers using
different techniques which most stencil designed to be
applied as solid colors. Multiple layer of stencil are used on
the same surface to produce multi colored images.
20. BLOCK PRINTING
Textile printing is the process of applying color of fabric is
defined patterns are design. In properly printed fbric the
colouris bonded with the fibre so as to resist washing and
friction. Textile printing is related to dying but in dying
properly the whole fabric is uniformly covered with one
colour, in printing one or more colours are applied to within
certain parts only and in sharply defined patterns.
In printing, wooden block, stencil, engraved plates, roller or
silk screen can be used to place colors on the fabric.
Colorants’ used in printing contains dyes thickened to
prevent the color from spreading capillary attraction beyond
the limits of the pattern are design.
21. FLOCK PRINTING
Flock printing is an old technique which was already in use
china around 1000 BC. In Europe it became in popular during
the middle ages.
Flock printing or flocking is a printing process in which short
fiber of rayon cotton wool or another natural or synthetic
material or applied to an adhesive coated surface. This adds a
velvet studded-like texture to the surface. Since the fiber can
be dyed, flocking can also add a color to a printer area.
The fibers use in process or known as flock. They can we
applied to paper, plastic, metals textiles and even glass.
