Comparison of Physical Properties of Coatings on Paper Substrate after Curing by UV and Electron Beam
Article Sidebar
Main Article Content
Abstract
This study aimed to assess the curing efficacy of ultraviolet (UV) radiation and electron beam (EB) curing techniques and the physical attributes of coated overprint varnish (OPV) applied on paper substrates. Coating formulations with and without photo-initiator (PI) underwent UV irradiation at doses ranging from 0.561 to 1.612 J/cm2 and EB at doses ranging from 30 to 100 J/g. The investigation utilized Fourier-transform infrared (FTIR) spectroscopy to analyze the degree of conversion of double bonds in the cured samples, with a notable absorption peak observed at 810 cm-1 corresponding to C=C bonds in the acrylate group. Furthermore, EB curing exhibited polymer curing percentages ranging from 79% to 83%, similar to UV curing. Notably, the yellowness index of EB-cured coating films (ranging from 0.5 to 10) was lower than that of those cured with UV (ranging from 10 to 28). The study suggests that EB curing could serve as an alternative process, potentially reducing health hazards associated with photo-initiator migration and food contamination within packaging materials, thereby offering a promising future for the field.
Article Details
This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.
References
Schwalm, R. UV Coatings: Basics, Recent Developments, and New Applications. 1st ed. Amsterdam: Elsevier; 2007.
Shang, D., Sun, X., Hang, J., Jin, L., Shi, L. Preparation and stability of silica sol/TPGDA dispersions and its application in the UV-curable hybrid coatings for fire protection. J Sol-Gel Sci Technol. 2013;67:39–49.
Biro, D.A., Bishop, J. Advances in Electron Beam Curing in Wide Web Flexible Package Printing. UV and EB Technology. Proceedings of the Technical Association of the Graphic Arts, TAGA; 2017.
Ibrahim, M.S., Mohamed, H.A., Kandile, N.G., Said, H.M., Mohamed, I.M. Electron beam processed plasticized epoxy coatings for surface protection. Mater Chem Phys. 2011;130:237–42.
Kumar, V., Misra, N., Paul, J., Bhardwaj, Y., Goel, N., Francis, S., Sarma, K., Varshney, L. Organic/inorganic nanocom-posite coating of bisphenol A diglycidyl ether diacrylate containing silica nanoparticles via electron beam curing process. Prog Org Coat. 2013;76(7-8):1119-26.
Liu, P., Luo, J., Liu, X., Liu, R., Webster D.C. Effect of the nature of the reactive group on the electron beam curing of model urethane di (meth) acrylates. Prog Org Coat. 2020;138:105371.
Mehnert, R. Review of industrial applications of electron accelerators. Nucl Instrum Methods Phys Res Sect B Beam Interact Mater Atoms. 1996;113:81–7.
Salleh, N.G.N., Yhaya, M.F., Hassan, A., Bakar, A.A., Mokhtar, M. Effect of UV/EB radiation dosages on the properties of nanocomposite coatings. Radiat Phys Chem. 2011;80:136–41.
Xuecheng, J., Hongfei, H., Bo, J., Yong, Z. Synthesis of urethane acrylates modified by linseed oil and study on EBC coatings. Radiat Phys Chem. 1999;56:573–9.
Glöckner, P., Jung, T., Struck, S. & Studer K. Radiation Curing: Coatings and Printing Inks. Hannover: Vincentz Network; 2008.
Bauer. F, Decker, U., Naumov, S., Riedel, C. Photoinitiator-free UV curing and matting of acrylate-based nanocomposite coatings: Part 3. Prog Org Coat. 2014;77:1085–94.
Abdelhafidi, A., Babaghayou, I. M., Chabira, S.F., Sebaa, M. Impact of solar radiation effects on the physicochemical properties of polyethylene (PE) plastic film. Procedia Soc Behav Sci. 2015;195:2922-9.
Barres CE. Mechanism of vinyl polymerization I: Role of Oxygen. J Am Chem Soc. 1945;67:217.
Shin DH, Rawls RH. Degree of conversion and color stability of the light curing resin with new photoinitiator systems. Dent Mater. 2009;25:1030-8.
Timothy Edward Bishop. Liquid BAPO photoinitiator and its use in radiation curable compositions. European Patent Specification. 2010.
Van, M., Bossuyt, E., Van Hoeck, E., Vanhaecke, T., Rogiers, V., Mertens, B. Printed paper and board food contact materials as a potential source of food contamination. Regul Toxicol Pharmacol. 2016;81:10-9.
Defoort, B., Larnac, G., Coqueret, X. Electron-beam initiated polymerization of acrylate compositions 4: effects of pulsed irradiation parameters on curing kinetics. Radiat Phys Chem. 2001;62:47-53.
Shin, T.G., Lee, I., Lee, J., Hwang, J., Chung, H., Shin, K., Kim, J. Electron beam curing of acrylated epoxy resins for anisotropic conductive film application. Thin Solid Films. 2013;547:246-9.
Wei, D., Liao, B., Huang, J., Zhang, M., Pang, H. Fabrication of castor oil-based hyperbranched urethane acrylate UV-curable coatings via thiol-ene click reactions. Prog Org Coat. 2019;135:114-22.
Arsu, N., R. S. Davidson, R. Holman. Factors affecting the photoyellowing which occurs during the photoinitiated polymerization of acrylates. J Photochem Photobiol A Chem. 1995;87:169-75.
Studer, K., R. Koniger. Initial photoyellowing of photocrosslinked coatings. Eur Coat J. 2001;1-2:26-58.
Chao W, Bing C, Lik-ho T, Li H. Yellowing mechanisms of epoxy and vinyl ester resins under thermal, UV and natural aging conditions and protection methods. Polym Test. 2022;114:107708.
Bohumil, J,. Influence of printing speed and radiation dose on the curing of uv inks and varnishes. 9th International Symposium on Graphic Engineering and Design. 2018; 333-9.
Anan, K., Thananchai, P., Parichart, K., Soraya, W., Pichayada, K., Wanvimol, P. Electron beam-cured linseed oil - Diacrylate blends as a green alternative to overprint varnishes: Monitoring curing efficiency and surface coating properties. Radiat Phys Chem. 2022;199:2-14.
Bohumil, J., Janet, D., Valis., Tomas, Syrovy. Development of new UV LED curable inkjet varnishes. In: 11th International Symposium on Graphic Engineering and Design. 2022;101-5.
Adrian, J., Boas. UV-Cured Supermatt Surfaces With Low Migration. In: Inkjet Printing in Industry: Materials, Technologies, Systems, and Applications. 2022;1:951-76.
Chen, Z., Beiqing, H., Xianfu, W., Wei, Z., Zixin, L. Preparation and Characterization of UV Varnish with High Resistance. 2021. p. 620-8.