In binding and finishing, a process in which images, patterns, or text are stamped or pressed into a substrate. In the embossing process, a relief die or embossing form is mounted to a platen beneath the substrate to be stamped. A counter embossing form—or a sunken die into which the relief die fits exactly—is mounted to a platen directly above the substrate. During embossing, the two dies are pressed together through the substrate, which creates a raised image. Often, the dies are heated. Embossing which simply stamps an image with no additional coloration or decoration of the pattern is known as blind embossing. Embossing which is combined with foil stamping to transfer a foil image to the embossed pattern is known as foil embossing.
In the process of debossing—which is the reverse of embossing, or the created of a sunken image—the positions of the relief die and the counter die are reversed. A similar process in which a sunken image is pressed into a hard book cover or other such substrate is known as die-stamping.
Embossing dies are made of brass, magnesium, or copper. Brass is especially useful for long runs. A brass die used in stamping book covers is called a binder's brass or, when made from other metals, a binder's die. The image itself can be chemically etched, machine-cut, or hand-tooled. Increasingly, dies are manufactured using lasers guided by CAD/CAM computer software. Embossing can be done before or after printing. See Die and Binding and Finishing.
In papermaking, embossing is a paper finishing operation in which paper is impressed with a raised design. A machine used for embossing is similar to a supercalender, in which a hard steel roll containing the raised design to be stamped on the paper is in contact with a soft compressible roll. As the paper web passes through the nip of these rolls, the design is stamped on it. The process is used for embossed finish papers, and papers with other heavily-textured surfaces.