offset-printing-machine

Offset Printing

Offset Printing

Offset printing is a commonly used printing technique in which the inked image is transferred (or “offset”) from a plate to a rubber blanket, then to the printing surface. When used in combination with the lithographic process, which is based on the repulsion of oil and water, the offset technique employs a flat (planographic) image carrier. Ink rollers transfer ink to the image areas of the image carrier, while a water roller applies a water-based film to the non-image areas. The modern “web” process feeds a large reel of paper through a large press machine in several parts, typically for several metres, which then prints continuously as the paper is fed through. Development of the offset press came in two versions: in 1875 by Robert Barclay of England for printing on tin, and in 1904 by Ira Washington Rubel of the United States for printing on paper.