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The gravure process has its origins in the early seventeenth century
when the intaglio printing process was developed to replace woodcuts in
illustrating the best books of the time. In early intaglio printing,
illustrations were etched on metal, inked, and pressed on paper. Gravure,
still also known as intaglio printing, makes use of the ability of ink to
adhere to a slight scratch or depression on a polished metal plate.
Currently, the dominant gravure printing process, referred to as
rotogravure, employs web presses equipped with a cylindrical plates (image
carrier). A number of other types of gravure presses are currently in use.
Rotary sheet-fed gravure presses are used when high quality pictorial
impressions are required. They find limited use, primarily in Europe.
Intaglio plate printing presses are used in certain specialty applications
such as printing currency and in fine arts printing. Offset gravure
presses are used for printing substrates with irregular surfaces or on
films and plastics.
Today almost all gravure printing is done using engraved copper
cylinders protected from wear by the application of a thin electroplate of
chromium. The cylinders (image carrier) used in rotogravure printing can
be from three inches in diameter by two inch wide to three feet in
diameter by 20 feet wide. Publication presses are from six to eight feet
wide while presses used for printing packaging rarely exceed five feet. in
width. Product gravure presses show great variation in size, ranging from
presses with cylinders two inches wide, designed to print wood grain edge
trim, to cylinders 20 feet wide, designed to print paper towels. The
basics of Gravure printing is a fairly simple process which consists of a
printing cylinder, a rubber covered impression roll, an ink fountain, a
doctor blade, and a means of drying the ink.
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