Lista QR Code

Lithography

Centro di documentazione delle arti grafiche “Grifani-Donati” 1799

The planographic technique of printing, generally known as lithography, from lihtos, or stone, is based on the repelling of water and ink. The first person to use this technique was Aliosio Senefelder in 1796, who was born in Prague but who moved to Bavaria.

The drawing is done directly by the artist on the matrix, a lithographic limestone plate known as Solenhofen, from the German city that it came from. To draw, an oily crayon is used, made of wax and Marseille soap.

Once the drawing is done, the limestone is bathed in a solution composed of Arabic gum which, together with the Marseille soap and the wax from the wax crayon, will react chemically: the areas which have been drawn on or scratched, become lipophilic, drawing to it the ink that is oily, whilst, the white areas or non scratched areas become hydrophilic, i.e. they attract the water and repel the oily ink. The limestone is then placed in the lithographic printing press, where the pressure is registered, and subsequently, its surface is washed with turps (white spirit) that will melt the wax, the Marseille soap, and the black carbon of the pencil. This part of the process allows the matrix to absorb the humidity from the hydrophilic areas and to repel them in the lipophilic areas. Going over it with an ink-filled roller, this will be received and maintained only by the lipophilic areas, and therefore by the picture. Placing the pure cotton sheet of paper on the stone, it is pressed with the lithographic press and a print is made, characterised by the presence of an irregular scratching thanks to the characteristics of the finer grain, of the stone, and of the absence on the reverse of markings typical in typography and in the face of embossed ink. The main advantages of this technique are the speed and the low cost of the process, the ease with which you can combine pictures and text on the plate as well as the possibility to get an almost limitless number of print runs, thereby reaching a more extensive audience.

Grifani Donati Typography has a star printing press made by the company Bollito & Torchio of Turin in 1880, and which is in perfect functioning condition.

Litografia