Abstract
Curcuminoids are a group of naturally occurring polyphenolic compounds found in turmeric (Curcuma longa) that are widely employed as coloring agents in traditional medicine and the food industry. Moreover, they have been used as dyes in pH indicators, which are part of diagnostic intelligent packaging. Recently, there has seen a steady increase of the interest in the curcuminoids due to their fluorescent property. In this study, a curcuminoid dye (CurD) containing a total curcuminoid content of 38.34 ± 0.66 % w/w was prepared by using a microwave-assisted extraction, and was used as a multifunctional dye with different commercial screen binders, including solvent-based ink (Si) and water-based ink (Wi). A solution of CurD (0.1 % w/v) exhibited a maximum fluorescence wavelength of 526 nm. Based on the print-quality test using a screen printing on clear polyvinyl chloride and paper, the viscosity and drying time of CurD-Si and CurD-Wi inks were not significantly different. The printed-inks had a yellow color under illuminant D50 and D65, and exhibited remarkable green fluorescence under UVA (365 nm). The total color differences (∆Eab∗), which are not fluorescence intensities, of both inks were changed by increasing CurD concentrations. CurD-Wi containing 1 % w/w CurD could be printed as latent graphics on a paper label for use as an anti-counterfeiting application. In addition, it immediately responded to alkaline solution and vapor through color transition from yellow to orange-brown, with the maximum ∆Eab∗ values of 15.02 and 26.62, respectively. In contrast, all CurD-Si samples could fluoresce but did not respond to alkaline conditions.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.