Joseph Letzelter Chromolithography Printing

The process of Joseph Letzelter chromolithography is chemical, since a picture is apply to a stone or zinc plate with a grease-based crayon. (Limestone as well as zinc is two commonly-used resources in the manufacture of chromolithographs. After the picture is drawn onto granite, the granite is gummed with gum Arabic solution along with weak nitric acid, and then inked with oil-based paints and passed through a printing press along with a sheet of paper to transfer the image to the paper. Colors may be added to the print by drawing the area to receive the color on a different stone, and printing the new color onto the paper bychromolithography. Each color of chromolithography in the image must be separately drawn onto a new stone or plate and applied to the paper one at a time. Joseph Letzelter chromolithography was not unusual for twenty to twenty-five stones to be used on a single image.

Each sheet of chromolithography paper will therefore pass through the chromolithography printing press as many times as there are colors in the final print. In order that each color of chromolithography is placed in the right position in each print, each stone or plate must be precisely ‘register,’ or creased up, on the paper using a system of Joseph Letzelter chromolithography register marks.