Textile printing is the process of applying colour to fabric in definite patterns or designs. In properly printed fabrics the colour is bonded with thefiber, so as to resist washing and friction. Textile printing is related to dyeing but, whereas in dyeing proper the whole fabric is uniformly covered with one colour, in printing one or more colours are applied to it in certain parts only, and in sharply defined patterns.
In
printing, wooden blocks, stencils, engraved plates,
rollers, or silkscreens can be used to place colours on the fabric.
Colourants used in printing contain dyes thickened to prevent the colour
from spreading by capillary attraction beyond the limits of the pattern or design.
Traditional
textile printing techniques may be broadly categorised into four styles:
Direct printing, in which colourants containing
dyes, thickeners, and the mordants or substances necessary for fixing the colour on the cloth are
printed in the desired pattern.
The printing of a mordant in the desired pattern
prior to dyeing cloth; the color adheres only where the mordant was printed.
Resist dyeing, in which a wax or
other substance is printed onto fabric which is subsequently dyed. The waxed
areas do not accept the dye, leaving uncoloured patterns against a coloured
ground.Discharge printing, in which a bleaching agent
is printed onto previously dyed fabrics to remove some or all of the colour.
Resist and discharge techniques were particularly
fashionable in the 19th century, as were combination techniques in which indigo resist
was used to create blue backgrounds prior to block-printing of other colours.[1] Most
modern industrialised printing uses direct printing techniques.
Woodblock printing is a technique
for printing text,
images or patterns used widely throughout East Asia and
probably originating in China in antiquity as a method of printing on textiles and
laterpaper.
As a method of printing on cloth, the earliest surviving examples from China date
to before 220.
Textile
printing was known in Europe, via the Islamic world, from about the 12th
century, and widely used. However, the European dyes tended to liquify, which
restricted the use of printed patterns. Fairly large and ambitious designs were
printed for decorative purposes such as wall-hangings and lectern-cloths,
where this was less of a problem as they did not need washing. When paper
became common, the technology was rapidly used on that for woodcut prints.
Superior cloth was also imported from Islamic countries, but this was much more
expensive.
The Incas of Peru, Chile
and the Aztecs of Mexico also practiced textile printing previous to the
Spanish Invasion in 1519; but owing to the imperfect character of their records
before that date, it is impossible to say whether they discovered the art for
themselves, or, in some way, learned its principles from the Asiatics.
During the
later half of the 17th century the French brought directly by sea, from their
colonies on the east coast of India, samples of Indian blue and white resist
prints, and along with them, particulars of the processes by which they had
been produced, which produced washable fabrics.
There are
seven distinct methods at present in use for producing coloured patterns on
cloth:
Hand
block printing
This
process, though considered by some to be the most artistic, is the earliest,
simplest and slowest of all methods of printing.
In this
process, a design is drawn on, or transferred to, a prepared wooden block. A
separate block is required for each distinct colour in the design.
A
blockcutter carves out the wood around the heavier masses first, leaving the
finer and more delicate work until the last so as to avoid any risk of injuring
it during the cutting of the coarser parts. When finished, the block presents
the appearance of flat relief carving, with the design standing out.
Fine details
are very difficult to cut in wood, and, even when successfully cut, wear down
very rapidly or break off in printing. They are therefore almost invariably
built up in strips of brass or copper, bent to shape and driven edgewise into
the flat surface of the block. This method is known as coppering.
To print the
design on the fabric, the printer applies colour to the block and presses it
firmly and steadily on the cloth, ensuring a good impression by striking it
smartly on the back with a wooden mallet. The second impression is made in the
same way, the printer taking care to see that it fits exactly to the first, a
point which he can make sure of by means of the pins with which the blocks are
provided at each corner and which are arranged in such a way that when those at
the right side or at the top of the block fall upon those at the left side or
the bottom of the previous impression the two printings join up exactly and
continue the pattern without a break. Each succeeding impression is made in
precisely the same manner until the length of cloth is fully printed. When this
is done it is wound over the drying rollers, thus bringing forward a fresh
length to be treated similarly.
If the
pattern contains several colours the cloth is usually first printed throughout
with one, then dried, and printed with the second, the same operations being
repeated until all the colours are printed.
Block
printing by hand is a slow process it is, however, capable of yielding highly
artistic results, some of which are unobtainable by any other method.
Stencil printing
The art of
stenciling is not new. It has been applied to the decoration of textile fabrics
from time immemorial by the Japanese, and, of late years, has found increasing
employment in Europe for certain classes of decorative work on woven goods for
furnishing purposes.
The pattern
is cut out of a sheet of stout paper or thin metal with a sharp-pointed knife,
the uncut portions representing the part that is to be reserved or left
uncoloured. The sheet is now laid on the material to be decorated and colour is
brushed through its interstices.
It is
obvious that with suitable planning an all over pattern may be just as easily
produced by this process as by hand or machine printing, and that moreover, if
several plates are used, as many colours as plates may be introduced into it.
The peculiarity of stenciled patterns is that they have to be held together by
ties, that is to say, certain parts of them have to be left uncut, so as to
connect them with each other, and prevent them from falling apart in separate
pieces. For instance, a complete circle cannot be cut without its center
dropping out, and, consequently, its outline has to be interrupted at
convenient points by ties or uncut portions. Similarly with other objects. The
necessity for ties exercises great influence on the design, and in the hands of
a designer of indifferent ability they may be very unsightly. On the other
hand, a capable man utilizes them to supply the drawing, and when thus treated
they form an integral part of the pattern and enhance its artistic value whilst
complying with the conditions and the process.
For
single-colour work a stenciling machine was patented in 1894 by S. H. Sharp. It
consists of an endless stencil plate of thin sheet steel that passes
continuously over a revolving cast iron cylinder. Between the two the cloth to
be ornamented passes and the colour is forced on to it, through the holes in
the stencil, by mechanical means.
Screen-printing
Screen
printing is by far the most used technology today. Two types exist:
rotary screen printing and flat (bed) screen printing. A blade squeezes the
printing paste through openings in the screen onto the fabric.
Digital
textile printing
Digital textile printing,often referred to as direct to garment printing, DTG
printing, and digital garment printing is a process of printing on textiles and
garments using specialized or modified inkjet technology. Inkjet printing on
fabric is also possible with an inkjet printer by using fabric sheets with a
removable paper backing. Today major inkjet technology manufacturers can offer
specialized products designed for direct printing on textiles, not only for
sampling but also for bulk production.
Since the early 1990s, inkjet technology
and specially developed water-based ink (known as dye-sublimation or disperse
direct ink) has offered the possibility of printing directly onto polyester
fabric. This is mainly related to visual communication in retail and brand
promotion (flags, banners and other point of sales applications). Printing onto
nylon and silk can be done by using an acid ink. Reactive ink is used for
cellulose based fibers, such as cotton and linen. Using inkjet technology in
digital textile printing allows for single pieces, mid-run production and even
long-run alternatives to screen printed fabric.
Example of printing
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