The light pressure - A short introduction
For many connoisseurs of art all over the world, the light printing is the ideal alternative to the often unique - much coveted - original. For collectors, the antiquarian character of classic light printing is becoming increasingly important. Valuable materials, such as laid paper or litho cardboard, make it possible to fully exploit the uniquely versatile palette of the artisan art of the light printing process. This is guaranteed by our logo.
The approximately 150-year-old photogravure method is considered the noblest - but also the most difficult, the most elaborate and
most expensive - reproduction technique in printing. This highly specialized printing process is dying out worldwide!
As far as we know, there are only 3 printers left who still master this printing process
and apply.
First: The photographic color separation.
First of all, halftone negatives in the size of the desired light pressure are made by photographic means - if possible by reference to the original - for each required color. These negative films are processed by trained retouchers with a lot of color feeling by hand, so that the finished light pressure as close to the original as just possible.
Second: transfer of individual separations on prepared glass plates.
Each halftone negative is copied onto a glass plate (halftone positive) coated with organic gelatin. Exposure to UV radiation produces a chemically induced, differentiated tanning process on gelatine. With twelve colors, twelve plates are needed. The process of delicacies creates microscopic "wrinkles" that are the secret of the nature of multicolour light pressure.
The actual printing process.
It not only requires heavy specialized machines, but also the highest artisanal printing experience. The light ink is applied by hand to the ink roller, by means of which the printing plate is colored. The prepared plate then prints directly onto the paper. Each color separation requires its own printing process with subsequent drying. Due to the abrasion of the organic mass on the plate during the printing process only small maximum runs are possible. In addition, with each color / printing process, part of the overlay is inevitably rejected.
The principle here / the secret behind it.
The light pressure principle works by the antagonism of fat (= color) and water (= glycerine-water mixture). The UV-exposed areas of the printing plate are "tanned" depending on the intensity. Only at the exposed swellable places by moisture absorption, the color is repelled. This happens more or less differentiated depending on the exposure. In addition, the swollen wet spots emerge upwards, so that at the tanned places - depending on exposure and swelling - real halftones possible. The brilliance and plasticity of the image - as with the original - also brings the high-fat ink.
