All about Colour

Featured image by Dr Susanne Klein: lithograph, print size 20 x 20 cm, Spectraval pigments in linseed oil on 240 gsm Plike black paper.

We are delighted to be part of the Society of Dyers and Colourists Special Issue on Challenges and Open Problems in Colorimetry. All the authors in the special issue explore and address the complexities of colour reproduction, printing, perception and appearance in this fast changing and complex field.

The article by Parraman and Klein explores the relationship between additive and subtractive mixing for colour printing. Using Spectraval mica pigments (Merck)—marketed as RGB pigments—colour is generated by selective reflection and prints are based on additive colour mixing principles, that when printed onto black paper, create white and a range of colours. Although currently used mostly for decorative effects, they can be the basis of additive ‘process’ inks, that present new opportunities for and challenges to traditional print markets. The viewing angle dependency of their selective reflection favours applications in security printing similar to the holograms on bank cards for example. Traditional measurement and modelling methods are difficult to apply due to the layering and irregular dispersion of pigments.

We would like to thank SDC Coloration Technology Editors Professor Stephen Westland (Leeds University) and Professor Alessandro Rizzi (Università degli Studi di Milano),

Also thanks to The Society of Dyers and Colourists and Merck Chemicals.

A similar paper – Colour Deceives Continually – was presented on 28 Jan 2021 at Color Imaging XXVI: Displaying, Processing, Hardcopy, and Applications. The Institute of Science and Technology:

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