Litho Guide

The primary purpose of the printing industry is to create and manufacture products that communicate visually. The printing process known as offset lithography dates back over 200 years. In offset printing, the image on the plate is transferred to the rubber blanket on the blanket cylinder. The rubber blanket then transfers or offsets, the image to the paper. Offset lithography is also called planography because the printing areas are on the same plane as the surface of the printing plate. Offset lithography is based on the principle that water and grease do not readily mix. During printing, the image areas accept only the lithographic ink, and the nonimage areas accept only water. There have been many technological advancements within offset lithography from digital presses to CTP (Computer to Plate) technology. Before a beginner learns about the new advancements, it is important that he or she learn the basic pre-press and press techniques used in the past. LITHOS was designed to help beginner Lithography students go through the pre-press, press, and post-press steps for a basic one-color design.

James Howard is a Graduate Assistant in the Department of Graphic Communication Systems and Technological Studies, School of Technology, North Carolina Agricultural and Technical State University, Greensboro, NC.