PRINTING METHODS

PRINTING

SPECIFICATIONS

Textile printing is the process of applying colour to fabric in definite patterns or designs. In properly printed fabrics the colour is bonded with the fiber, 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 are 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:

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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.
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The printing of a mordant in the desired pattern prior to dyeing cloth; the color adheres only where the mordant was printed.
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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.
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Discharge printing, in which a bleaching agent is printed onto previously dyed fabrics to remove some or all of the colour.


PRINTING


ORIGIN
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 later paper. As a method of printing on cloth, the earliest surviving examples from China date to before 220, and from Egypt to the 4th century.Textile printing was known in Europe, via the Islamic world, from about the 12th century, and widely used. However the European dyes tended to run, 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 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.


METHODS OF PRINTING


There are six distinct methods at present in use for producing coloured patterns on cloth:

1. Hand block printing.
2. Perrotine or block printing by machine.
3. Engraved plate printing.
4. Engraved roller printing.
5. Stenciling, which although not really a printing process may be classed here as one.
6. Screen printing