Chryssa

Lithography is the most recently developed technique in printmaking. It falls under the general category of planographic printing because the design is on the same plane as the plate that carries the artwork.

The lithographic technique was discovered between 1796 and 1798 in Munich by the German-born playwright and musician Aloys Senefelder (1771-1834), who was born in Prague and was seeking a cost-effective way to print his works. Quickly, lithography surpassed other printmaking techniques and methods because it offered greater painterly qualities with smooth tonal transitions and richer color gradations, while also ensuring a higher number of prints, especially for posters.

Lithography should not be confused with offset printing. It is also important to distinguish between lithographic prints and photo-lithographic (photomechanical) reproductions: in the former, the lithographer transfers an artist's original work onto stone or zinc, whereas, in the latter, the original work is photographed and printed using offset.

The lithographic technique is based on the principle that oil repels water. The lithographer draws—not engraves—the artwork on a cleaned and smooth limestone plate using greasy pencils (crayons) or chemical inks based on wax, soap, and soot, applied with either a pen or brush. The design is then fixed with a solution of gum arabic and nitric acid, left to oxidize for at least twelve hours, and then washed with water and turpentine, ensuring that the plate remains continuously moist with the help of a sponge. Water does not adhere to the areas of the plate that have been lubricated and drawn on with crayon or chemical ink. Next, paper is placed on the inked surface and printed using a press.

The cumbersome stone was later replaced for convenience with sheets of zinc (zinc lithography) or aluminum. Modern types of lithography include autography, airbrush lithography, imitation etching lithography, diluted ink lithography, relief lithography, and imitation needle lithography. In color lithography—distinguished from chromolithography, which involves mass printing of color lithographs—different plates are used for each color, similar to woodcut and copperplate engraving. Other lithographs may be hand-colored.