Glossary of terms

Technical terms simply explained

“K” international abbreviation for the achromatic process printing ink black (“key”)

Kelvin kelvin SI unit of measure K (without ° symbol) named after the British physicist William Thomson Kelvin of Largs for the absolute temperature T. With color temperatures, conversion into °C or °F is not permissible.

keyless inking, short ink-train technology technologie d’encrage court process group adapted by KBA from flexoprinting for offset printing and optimized for waterless offset (sheet-fed offset: Gravuflow and MetroPrint, coldset: Newsflow) for non-ghosting print forme coloring; features: keyless blade chamber instead of ink duct, temperature-adjustable screen roller instead of fountain roller, ink forme roller(s) with blanket instead of ductor roller, distributor drum (except Newsflow) and rubber rollers, temperature-adjustable plate cylinder.

Kubelka-Munk see absorption-to-scattering ratio

Küppers’ color theory théorie des couleurs de Küppers theory of color perception and color rendering developed by Harald Küppers, not based on CIE recommendations or DIN standards and for this and other reasons controversial; Küppers redefined the maxima of the 3 cone sensitivity levels, unlike the CIE values 1931, namely 448 nm for blue (V, “violet blue”), 518 nm for green (G) and 617 nm for red (O, “orange red”). On this he based the first hifi color printing ink series in the world, the 7-part Küppers scale CMY-OGV-K, which was the model for similar scales, e.g. Pantone Hexachrome. Regardless of his special color theory, “The Great Kueppers Color Atlas” is still one of the most significant books on color rendering in the printing industry.