Coatings in graphic industry

Abstract

Contrary to the negative predictions, the graphic arts industry keeps continuing its growth. The modern world is transferring information through digital platforms leading to decrease of the serial publications on paper (newspaper, magazines etc). But on the other hand, packaging industry is increasing its revenue by high numbers. In the same way as for the whole industry, many predicted that paper use will also decrease, as for a long period of time (still partly present) paper was thought of as being killer of trees. Today, along with new findings, paper is becoming more popular with EU Commission banning single use plastics. Paper as a substrate is becoming popular in packaging industry, mainly due to being suitable for both organic and material recycling. However, due to lack of some functional properties, materials are often coated. Coating as a process includes covering of a surface by another substance. The coatings processes are present in various industries and are intended to enhance properties of the base materials. In the graphic industry the coating process is often called varnishing, due to the resins used as a coating material. Varnishing is used to improve rub resistance and provide varnished material with special effects (combination of gloss and matte surfaces). Applicability and functionality of the coatings is achieved using various materials, among which are nano-engineered materials. Results of various researchers show benefits of introducing nanocomposites in the packaging industry by improving prints’ resistance to degradation by UV irradiation, improving barrier to water vapour and enabling packaging surface to inhibit microbes’ growth. To conclude, coatings development and application plays a significant role in the material development, as it can provide common materials with improved properties, as well as enhanced aesthetics. At the same time, application of coatings could present some obstacles in both materials and organic recycling, and for that reason development of coatings should include evaluation of recyclability of the coated product as well as the characterization of coating’s functionality.