RT info:eu-repo/semantics/article
T1 Chromogenic Anticounterfeit and Security Papers: An Easy and Effective Approach
A1 Guirado Moreno, José Carlos
A1 Guembe García, Marta
A1 García Pérez, José Miguel
A1 Aguado, Roberto
A1 Valente, Artur J. M.
A1 Vallejos Calzada, Saúl
K1 Anticounterfeit
K1 Papers
K1 Azo-coupling
K1 Sensory polymers
K1 Colorimetry
K1 RGB parameters
K1 Química orgánica
K1 Chemistry, Organic
AB The synthesis and preparation of 12 chromogenic polymers used to build an intelligent label for security paper applications are described. The process involves coating paper sheets with the polymers. Depending on the number of different polymers used in a combinatory way, a maximum of 1212 combinations is possible, thus creating a matrix that is practically impossible to counterfeit. Currently, most anticounterfeiting proposals for paper-based packaging and documents involve some sort of verification under ultraviolet radiation, and the requirement of additional equipment often relegates the end-user to a passive role. In contrast, in our approach, the combination of sensory polymers in an array gives rise to an invisible label, i.e., an owner cryptographic key, which becomes visible upon scattering a nitrite solution (e.g., spraying or using an impregnated foam roller) over the printed label on the security paper. For this purpose, a monomer containing an aromatic primary amino group and another with an activated aromatic ring are covalently bonded to a polymer with high affinity toward paper, consisting essentially of units of methyl methacrylate and 1-vinyl-2-pyrrolidone. Subsequently, the paper samples are coated with the resulting sensory chromogenic polymer. By spraying, painting, or staining an aqueous acid solution of NaNO2 (at least 1.20 g/L) and the chromogenic polymers, a well-defined color appears, because of the formation of an azo compound. This process provides users with a quick and facile authentication method without additional equipment and without affecting paper strength.
PB American Chemical Society
SN 1944-8244
YR 2021
FD 2021-12
LK http://hdl.handle.net/10259/6360
UL http://hdl.handle.net/10259/6360
LA eng
NO S.V. received funding from “La Caixa” Foundation (Grant No. LCF/PR/PR18/51130007). J.M.G. received funding from “Spanish Agencia Estatal de Investigación “ Grant No. PID2020-113264RB-I00/AEI/10.13039/ 501100011033. A.V. received funding from Portugal 2020 in the frame of COMPETE 2020 No. 246/AXIS II/2017 (Project No. 21874). We also gratefully acknowledge European Regional Development Fund (ERDF).
DS Repositorio Institucional de la Universidad de Burgos
RD 27-abr-2024