The Influence of UV Varnish on Colorimetric Properties of Spot Colors

Understanding the influence of UV varnishing on diversified tonality spot colors is significant in offset printing process. Versatility of various spot colors implies repeatability and correct reproduction. UV varnishing methods, besides enhancing the visual impact on the product, have a protective role, but due to the effect on different wavelengths spot colors can cause negative colorimetric changes. The research examined the impact of UV varnishing methods on printed spot colors on diverse printing substrates. The degree of change on prints caused by UV varnish was determined using spectrophotometric and densitometric methods. Research results are clearly showing the modality and the extent UV varnishing method causes on spot colors. This paper presents objective conclusions that help predict possible variations in spot colors, as well as limit values of colorimetric deviations that may affect the quality of the reproduction process.