Druckfarbenfabrik Gebr.schmidt Gmbh

Hans Bremer

Ernst E Schumacher

Rolf Herold

A multicolor printing method for reproducing varicolored images on substrates having a white surface by printing with inks of three primary colors, i.e. a color absorb blue (cab) which is a yellow, a color absorb green (cag) which is a red-violet and a color absorb red (car) which is a blue-green, producing printed colors having spectral density curves passing through matching ranges of optical densities at characteristic wavelengths in the visible spectrum, the ranges being within the following parameters: Range of  Optical density in % of D.sub.max Wavelengths cab    cag    car ______________________________________ 407 to 423 nm 65 to 93  2 to 27  39 to 79 453 to 456 nm 89 to 101 10 to 25  12 to 25 492 to 496 nm 60 to 74  65 to 81  1 to 10 538 to 541 nm 4 to 14  88 to 103 13 to 25 584 to 591 nm 1 to 3  50 to 75  65 to 88 633 to 646 nm 1 to 3   1 to 4  84 to 109 ______________________________________ D.sub.max marking the range of the maxima of the three spectral density curves, which is spaced from the optical density of the white surface D.sub.O by a distance corresponding to the density of the solid areas obtained by printing with normal inking.

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Nieder-Ramstadt, Germany

Hans Bremer