История письма и чтения. Асафова Г.К. - 134 стр.

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Heat-set inks require the application of heat to facilitate both the oxidation

process and the evaporation of the solvent, as well as the penetration of certain

elements that had rendered the ink more fluid. Cold-set inks are hardened by

chilling after printing, having been kept fluid by heat until they were applied to the

type form.

Moisture-set inks become fixed when they are applied directly to damp

paper or upon exposure to a water-spray after they are applied to dry paper. In such

inks, which are used more in the United States than they are in Europe, the vehicle

is a solvent, soluble in water,that, on contact, penetrates the paper, leaving the

pigment on its surface. Odourless moisture-set inks are used for printing food

packaging.

Among other special-characteristic inks are metallic inks containing

powdered copper, bronze, aluminum, or gold mixed with the pigment; magnetic

inks, containing a powdered magnetized iron mixed with the pigment for

“recognizing” the shape of printed characters as they pass before electronic reading

equipment; and fluorescent inks.

Rotogravure uses fluid inks in which the colouring agent, fixed on a natural

or synthetic resin, is integrated in a fluid solvent to which, just before printing, a

second, extremely volatile solvent is added.

Flexography also uses fluid inks whose pigments or colouring agents are

dissolved in pure alcohol, in alcohol solutions, or in water.

Serigraphy uses inks of extremely varied consistency, depending on the

surface to which they are to be applied; some are little different from ordinary

paint, except that their composition must not be such that rapid drying would clog

the mesh of the screen.