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vidual letters and characters could be rear- not mix. The image is first drawn or transferred
ranged to form words and sentences, was first onto a flat surface, typically a limestone block
developed in China in the 11th century and or a metal plate. The surface is then coated
later in Europe in the 15th century by Johannes with a mixture of gum arabic and nitric acid,
Gutenberg. which makes the image water-repellent. Ink is
then applied to the surface, which adheres to
In the 19th century, the invention of lithog- the image but not the surrounding areas.
raphy by Alois Senefelder enabled the print-
ing of high-quality images and text using a The surface is then dampened with water,
flat stone or metal plate. The invention of the absorbed by the non-image areas. This cre-
printing press revolutionised the production ates a barrier between the ink and the non-im-
of books and other printed materials, enabling age areas, preventing the ink from spreading
mass production on a scale that was previously beyond the intended image area. The ink is
impossible. This led to an explosion in liter- then transferred onto paper, either by press-
acy rates and spreading knowledge and ideas ing the paper onto the surface or by passing it
throughout Europe and beyond. Lithography through a press.
is based on the principle that water and oil do

Fig 4.1.2 A model of Lithography by Alois Senefelder

Lithography was particularly important in 4�1�2�2 Technologies Used in Print
the 19th century, as it allowed for the reproduc- and Publication
tion of high-quality images and text on a large
scale. This made it possible to produce books, Offset and Digital Printing
magazines, and newspapers with high-qual- Today, print and publication rely on various
ity illustrations and images. The process was technologies, from traditional offset printing to
also used for printing posters, maps, and digital printing and e-publishing. Offset print-
other large-format materials. The invention ing is the most common form used for books,
of lithography also had a significant impact magazines, and other printed materials. It is a
on the art world. It allowed artists to produce widely-used printing technique that has been in
high-quality prints of their work, which could use since the early 20th century. It involves the
be distributed more widely and at a lower cost transfer of ink from a printing plate to a rubber
than traditional methods such as engraving or blanket, which then applies the ink to the
etching. printing surface. The process is called “offset”

142 SGOU - FYUGP - SLM - English for Communication