Chapter 27 - Nano-inks and their applications in packaging industries

Abstract

Nanotechnology, which deals with dimensions on the nanometer scale, incorporates the use of atoms and molecules for industrial applications and has been rapidly converging with biotechnology in the rigid and flexible packaging industry. According to a study, nanotechnology has significantly increased its impact on the packaging industry. Nano-ink in particular has been the most significant contributor from the nanotech sector in the packaging industry and has opened up a new category of printing. Nano-ink has the distinct advantage of a combination of properties that usually are exclusive to water- or oil-based ink. This allows nano-inks to offer improved productivity and substrate range as well as print quality and cost compared with conventional inks. Such inks are prepared from synthesized nano-pigments and have physical properties similar to those of conventional inks while providing a wider range of color compared with conventional inks because of the particle size of nano-pigments, which are usually 20-200 nm in diameter. This is possible because of the formation of aggregates during dispersion. In comparison, particle sizes in conventional ink are usually more than 5 μm. This chapter focuses on the main functionalities made possible owing to the presence of nanomaterials in coatings and inks, with applications in food packaging. The main attention is on reviewing developments in mechanical, barrier, electrical and electronic, optical, and antimicrobial properties. The most important coating and printing technologies employed in the food packaging industry, such as flexography, rotogravure, offset, and inkjet, are discussed. Special emphasis is placed on their use with coatings and inks containing nanomaterials. Nano-safety and regulatory aspects regarding nanomaterials in food contact materials are also discussed. The chapter concludes by outlining future trends in and challenges to coating and printing technologies in the food packaging industry.