What Is Offset Printing?
Offset printing is a widely used printing technique where the inked image is transferred (or "offset") from a plate first 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 on which the image to be printed obtains ink from ink rollers, while the non-printing area attracts a film of water, keeping the nonprinting areas ink-free.
The advantages of offset printing include:
- Consistent high image quality — sharper and cleaner than letterpress printing because the rubber blanket conforms to the texture of the printing surface
- Usability on a wide range of printing surfaces in addition to smooth paper (e.g., wood, cloth, metal, leather, rough paper)
- Quick and easy production of printing plates
- Longer plate life than on direct litho presses — because there is no direct contact between the plate and the printing surface.