Ultraviolet inks

There are three main flexographic ink systems - water-borne, solvent-borne, and UV The primary difference between these ink systems is the method used for drying or curing the ink. Water and solvent-borne inks are dried by evaporation, whereas UV-cured inks are cured by chemical reactions. Flexo inks contain components that are responsible for several main functions, including solvents, colorants, resins, additives, and (for ultraviolet inks) UV-curing compounds. 

Ultraviolet Electron Beam Curing Formulations for Printing Ink, Coating and Paints, 3 Vols., SiTA Technology, London, 1991. 

Ultraviolet Photoinitiators. Photoinitiators are used in increasing volume for a multitude of appHcations. The most important of these are in the formulation of uv-curable inks and in the production of coatings on vinyl flooring, wood, and electronics components (28,29). The most common types of photoinitiators are phenone derivatives, for example, acetophenones and hen 7ophen ones (30). 

Feller, R. L., "Cross-Linking of Methacrylate Polymers by Ultraviolet Radiation", Preprints of papers presented at the New York Meeting, Division of Paint, Plastics and Printing Ink Chemistry, American Chemical Society, Sept., 1957, 17, No. 2, 465-470. 

Well over 100,000 high intensity ultraviolet curing units are in industrial use. Their main applications are surface curing of inks, coatings and adhesives. They typically operate in the 200 150 nm wavelength range, with lamp electrical power input as high as 240 W/cm (600 W/in.).1... 

It is used in the manufacture of polyvinylpyrrolidone (PVP), in the manufacture of copolymers with, for example, aciv lic acid, acrylates, vinyl acetate and acrylonitrile and in the synthesis of phenolic resins. About 10-15% of the monomer is used in the pharmaceutical industry for the production of PVP-iodine complex used as a disinfectant. It is also used as a reactive solvent of ultraviolet-curable resins for the production of printing inks and paints as paper and textile auxiliaries, and as an additive in the cosmetics industry (Harreus, 1993). 

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