also metallic effect, glow effect
Metallic paint consists of a conventional ink that has been enriched with metallic pigments. This effect pigments reflect incident light directed, comparable with tiny mirrors. Metallic colors are offered by different manufacturers as spot colors.
The metallic effect arises actually from powdered metals. However, golden color effect includes rare real gold. A golden impression is usually awakened with bronze, a silver impression with aluminum pigments. Metallic colors are applied directly or indirectly depending on the printing method. They behave like conventional printing inks, as they usually are based on those. However, the size of the effect pigments has an effect on the layer thickness and the useful printing method. They are often considerably larger than the pigments. Generally brings a thicker effect pigment layer also stronger effects.
As the name suggests, this effect colors evoke a metallic impression. This is perceived as high quality. Light reflected on the product, which is his due an increased attention.
In principle, this effect of color can be applied to any material that is suitable for conventional printing ink.
The size of the effect pigments has a direct influence on the usable pressure method and the resolution. The relatively large pigments usually have a diameter of 20 microns (see color pigments. 1 micron max.). This may result in screen printing already clogging the fabric pores. With fine fabrics with 150 threads / cm, for example, the spacing of the threads is only slightly larger than the pigments in.
Sources and additional literature
 Hille, Frauke Helene: Veredlungsmöglichkeiten und Spezialeffekte für Bücher und Broschuren; Diplomarbeit, Hochschule für Technik, Wirtschaft und Kultur Leipzig (FH), Fachbereich Medien, Studiengang Verlagsherstellung, 2008
 Murvai, Geza; Ober, Juliane: Inline-Veredelung im Bogen- und Endlosdruck. Bundesverband Druck und Medien, 2007
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