Gravure Printing

National Geographic magazine's features and much of it's contents are printed using the Gravure printing process. Gravure, sometimes referred to as Rotogravure, is an intaglio printing process. The image carrier has the image cut of etched below the surface of the non-image area. On the gravure image carrier [usually a copper cylinder-because copper can be reused and recycled], all the images are screened, creating thousands of tiny cells.

During printing, the image carrier is immersed in fluid ink. As the image carrier rotates, ink fills the tiny cells and covers the surface of the cylinder. Paper is brought into contact with the image carriers [with the help of an impression roller]. When the paper hits the image carrier, ink is drawn out of the cells onto the paper.

Dryers are usually used to dry each color as the paper goes through the printing process. You can read more about this process at the Gravure Association of America, Inc.