Embossing Press

a machine that embosses on book covers, cardboard, paper, plastics, and other sheet materials. The name “gilding press” was formerly used, when gold leaf was the principal material used to emboss book covers.

Crucible-equipped embossing presses have the simplest design. The upper platen, to which the die is attached, is stationary and equipped with heating devices. The lower platen is raised by a cam, which creates the required pressure of 0.35-1.75 meganewtons, or 35-175 tons-force. A board affixed to the lower platen travels with a reciprocating motion, thereby feeding the material under the die. If the lower platen and the board are operated manually, the hourly output of the press does not exceed 100 embossings. Mechanically or hydraulically driven presses have an hourly output of as many as 1,500 embossings (if the automatic feeder for covers is used, this figure can reach 2,700). In the improved, rotary embossing presses the die is attached to one cylinder, with the pressure being applied by another cylinder. The output of three-sectional machines of this type can be as high as 12,000–14,000 embossings per hour.

An embossing press can also do color printing. For this type of work the press is equipped with an apparatus consisting of a set of rollers. In most cases the embossing is done with the aid of a heated die, either without any coloring or with a dry pigment film or metal film (foil). An embossing press is also used to create a raised, or Congreve, impression. For this type of work a heated concave metal die is affixed to the upper platen, and a convex die, made of polyamide resin, is fastened to the lower platen.