Abstract
In the present research, the properties of ultraviolet (UV) visible (daylight invisible) fluorescent coatings modified by the addition of SiO2 and TiO2 nanoparticles were studied. Structural, surface, and mechanical properties and changes in the coatings caused by accelerated ageing were analyzed. The results showed that the addition of nanoparticles caused the changes in unaged and aged printed coatings. Reflectance measurements of modified coatings showed that addition of TiO2 nanoparticles improved the visual effect of the unaged coatings. Furthermore, results have shown that the addition of SiO2 did not diminish the reflectance of the modified coatings after ageing. The results of roughness measurements showed that the addition of SiO2 decreased roughness after the ageing process, probably due to the degradation process indicated by Attenuated Total Reflection Fourier Transform Infrared (ATR-FTIR) spectroscopy. The roughness of the coatings with TiO2 nanoparticles was increased after the ageing on the samples with higher concentrations of TiO2 due to the agglomerates of plastisol formed on the surface of the coatings, visible in SEM images. Surface analysis of coatings showed that TiO2 caused an increase in the polarity of the surface coatings. Results of the bending stiffness showed that the addition of the nanoparticles to the coating, especially of SiO2, significantly improved the bending stiffness of the unaged samples.
Highlights
UV visible fluorescent coatings (FC) belong to the group of luminescent materials that have the possibility of absorbing UV radiation and re-emitting of photons of a different radiation [1,2,3]
Nanocomposite—FCs consisted of the plastisol-based transparent base (TB) PLASTOLAK K73990K1 by Epta Inks (Eptanova S.R.L., Milano, Italy), UV visible fluorescent red pigment (FP red) by Cestisa and varied amount of SiO2 and TiO2 nanoparticles
The mass concentration of SiO2 nanoparticles added to the TB with FP red was set to 1%, 2%, and 3%, and the mass concentration of TiO2 nanoparticles was set to 0.5%, 1%, and 1.5%
Summary
UV visible (daylight invisible) fluorescent coatings (FC) belong to the group of luminescent materials that have the possibility of absorbing UV radiation and re-emitting of photons of a different radiation [1,2,3]. Development of suitable material that meets the specific printing requirements and ensures the optimal functional properties is of high importance due to the wide application of these kinds of coatings With this in mind, in this research, the properties of modified UV visible FC were studied. Colloidal silicon dioxide (fumed silica, SiO2) has many applications in the paints and coatings industry It is used as an anti-settling or suspension agent for fillers and pigments and it can be used as an electrically conductive coating containing metallic powders or lakes. It is used for rheology control of paints according to the application to improve the gloss and coloristic properties and for scratch resistance of different coating systems [26,27,28]. In order to evaluate the properties of modified coatings, the changes caused by the ageing process, surface, Coatings 2021, 11, 928 structural, and mechanical properties of printed coatings, and their visual responses were observed
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
