Introduction

The invention of lithography is credited to Alois Senefelder in 1798 in Munich, the Kingdom of Prussia (now Germany).

He became interested in letterpress printing and worked with different printing plates, inks and surface treatments.

Plate material in those days consisted of copper, which was expensive. Senefelder found that natural limestone worked well as an inexpensive plate surface after grinding it smooth and treating with a special etching fluid.

He developed a special “crayon” composed of wax, soap and lampblack which he initially used to make corrections on the copper and limestone plates.

The invention of lithography occurred by accident when his mother requested him to prepare a laundry list. Since he didn’t have a pen and paper close by he wrote it onto one of his smooth limestone plates with his correcting crayon. He then etched the plate surface with nitric acid. The portion which had been written in crayon was not attacked by the acid and stood about a “playing card” thickness in relief.

When dampened with water the porous limestone readily accepted water but rejected it in the crayon image area.

The image area was easily inked with an ink roller, but the wet non image area was not. The ink was transferred to paper by applying pressure to the back side in his printing press.

The force necessary to achieve good in transfer was about 1/4 of that necessary for his conventional plates. This process became known a shallow-relief printing.