Letterpress

Letterpress Printing

  Letterpress is the oldest method of printing with equipment and images printed by the “relief” type printing plates where the image or printing areas are raised above the non-printing areas. The use of letterpresses is on the decline being replaced with faster and more efficient printing presses such as the offset lithographic press or the flexographic press. The amount of setup required to prepare the equipment to print a job is significant. For example, the image must be metal cast prior to print versus offset printing plates which are comparatively cheaper and require less time to make.

 Letterpress printing exerts variable amounts of pressure on the substrate dependent on the size and image elements in the printing. The amount of pressure per square inch or “squeeze” is greater on some highlight dots than it is on larger shadow dots. Expensive,time consuming adjustments must be made throughout the press run to make sure the impression pressure is just right. Major chemicals used in letterpress printing, very similar to those used in lithography, include film developers and fixers, inks, and blanket and roller washes.