Interpreting the near-infrared reflectance of a series of perylene pigments

Abstract

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Synthesis, characterization and near infra-red properties of perylenebisimide derivatives

“…This result is in agreement with the study of B. Kaur et al [20]. Their computational study has shown that to achieve high reflectance/low absorbance in the NIR region, it is necessary to use pigments that have a minimal number of functional groups with high-frequency fundamental vibrations.…”

“…They concluded that no direct correlation between the nature of N-substituent and NIR reflectance of the samples could be established on the basis of their limited study. In another computational study, B. Kaur et al tried to interpret NIR reflectance of perylenebisimides and concluded that the UV-vis spectrum of the perylenebisimide molecules cannot significantly shift to NIR bands and the main factor contributing to NIR absorption is the overtone and combination modes of high frequency fundamental vibrational bands of the molecule [20]. They suggested that to achieve high reflectance in NIR region, it is necessary to use pigments that have a minimal number of functional groups with high-frequency fundamental vibrations, and sufficient symmetry so as to ensure that the molecules have no net dipole moment.…”

Synthesis and Characterization of Superhydrophobic, Self-cleaning NIR-reflective Silica Nanoparticles

“…As a counter measure, NIR reflective colorants are used as an effective means of reflecting such radiations. Since perylene derivatives have shown NIR reflectance810, it is conceivable that PDI functionalised silica nanoparticles will also exhibit such properties.…”

“…Furthermore, the high reflectance in the NIR region of the electromagnetic spectrum allows the incorporation of thermal insulating properties into materials8. Organic NIR absorbers have a wide range of applications such as invisible inks, NIR readable bar codes, laser-welding of plastics, laser induced thermal curing9, and energy saving applications10.…”

“…Organic NIR absorbers have a wide range of applications such as invisible inks, NIR readable bar codes, laser-welding of plastics, laser induced thermal curing9, and energy saving applications10. The origin of the NIR reflectance is due to the high refractive index of the perylene derivatives incorporated on various coatings810. NIR fluorescent nanoparticles are useful as they provide negligible background fluorescence, low-inner-filtration interference in complex biological systems such as whole blood11 and used as substrates for the characterization of enzymatic processes12.…”