Anti-counterfeiting strategy based on multiwavelength photothermal particles to disclose thermal imaging
Por:
Molina-Gonzalez, Jorge, Ramirez-Garcia, Gonzalo, Desirena, Haggeo, Meza, Octavio
Publicada:
1 abr 2022
Resumen:
Product counterfeiting is a major problem worldwide, not only because of
the economic losses but also because of the negative impact it has on
society. Therefore, it becomes a constant need to propose advanced
anti-counterfeiting methods or technologies which, ideally, should be
non-cloneable, easy to implement, difficult to remove-reuse, and
versatile. Although numerous systems already exist on the market or in
the literature, some of them lack of the above specifications, which
complicates their actual implementation. In this contribution, an
easy-to-print, safe and non-restrictive anti-counterfeiting system based
on the generation of thermal images by the photothermal effect of
LaBO3:Ln(3+) particles is proposed. Wavelength excitation, 808 or 975
nm, for photothermal effect can be tuned by selecting properly the
lanthanide ion (Nd or Yb). The temperature generated by the synthesized
samples covers a range from 25 to 300 degrees C approximately, when
excited with the appropriate infrared laser diode (LD) at powers from
0.015 to 2.1 W. Using a simple screen-printing method, codes were
printed using the LaBO3:Ln(3+) and LaBO3:Ln(3+) particles, which allow
the generation of simple or complex thermal images under appropriate
infrared laser radiation. The combination of the two synthesized
materials allows the generation of codes whose decoding is subject to a
specific sequence dependent on the excitation wavelengths. As a proof of
concept, the generated codes are printed on various drug packaging, as
well as on banknotes and business cards. Printing versatility and the
security level generated by the sequence of multiple excitation
wavelengths of thermal and visible codes allow the proposed system to be
used in printed security applications.
Filiaciones:
Molina-Gonzalez, Jorge:
Centro de Investigaciones en Optica, A.P. 1-948, Leon, Guanajuato, 37150, Mexico
Ramirez-Garcia, Gonzalo:
Biofunctional Nanomaterials Laboratory, Centro de Física Aplicada y Tecnología Avanzada, Universidad Nacional Autónoma de México, 3001, Blvd. Juriquilla, Querétaro, 76230, Mexico
Desirena, Haggeo:
Centro de Investigaciones en Optica, A.P. 1-948, Leon, Guanajuato, 37150, Mexico
Meza, Octavio:
Instituto de Física, “Ing. Luis Rivera Terrazas”, Benemérita Universidad Autónoma de Puebla, Apartado Postal J-48, Puebla, 72570, Mexico
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