Trükiplaadi

A trükiplaad is a substrate that carries the printed image used in various printing processes. The image area accepts ink while non-image areas repel ink, allowing transfer to paper or other substrate.

There are several types of trükiplaad: relief plates used in letterpress printing with a raised image; intaglio plates in which the image is etched or engraved into the surface; and planographic plates used in lithography and offset printing, where the image area remains flat and ink adheres to it while the surrounding areas repel ink.

In modern offset printing, plates are typically made of metal such as aluminum, or from photopolymer or thermal materials. The image is created photographically or digitally and then converted into a printable form on the plate in a platemaking process. Many systems use computer-to-plate workflows that directly transfer digital images to the plate.

The workflow generally includes image creation, platemaking, mounting on the press, inking, and transfer of ink to the substrate. The plate must maintain stability and precise image reproduction; worn or damaged plates are replaced to avoid quality loss.

Historically, lithography emerged in the late 18th century, and offset lithography became dominant in the 20th century. Plate technology evolved from chemical processes to digital and computer-to-plate systems, improving speed, consistency and environmental aspects.