Embossing is impressing a relief pattern on flexible sheet materials, such as paper, leather, rubber, plastic, and metal, or on textiles. The relief designs and textures on some wallpaper, paper napkins, stationery, and plastic rainwear and automobile seat covers are usually embossed. Leather bookbindings, silver dishes, and dress fabrics may also bear embossed designs. The technique is so sophisticated that the texture of oak bark can be reproduced on wallpaper and alligator grain on cowhide or plastic.
Embossing, unlike repoussee, chasing, or other means of making a relief pattern, is accomplished mechanically, not by hand. The material to be embossed - for example, a strip of wallpaper - is placed between two surfaces like a slice of ham between two slices of bread. The underside of the top (positive) surface bears a raised image, while the upper side of the bottom (negative) surface bears the same image but depressed. When the two surfaces are squeezed together under pressure so that the relief exactly fills the depression, the wallpaper in the middle will be embossed with the relief image on the lower side and the depressed image on the upper.
Continuous strips of material, such as wallpaper or cloth, are usually embossed between two rollers. Noncontinuous material, such as leather, is embossed between a steel plate and a plate of a more yielding substance, such as compressed paper.