Multicolor Photochemical Printing Inside Polymer Matrices for Advanced Photonic Anticounterfeiting
Yu Dong1,2,3, Huacan Wu1,2,3, Jie Liu1,2,3
1State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, 155 Yangqiao West Road, Fuzhou, Fujian, 350002, P. R. China.
Advanced Materials (Deerfield Beach, Fla.)
|March 28, 2024
Summary
New phototransformer molecules offer advanced security features for polymer films. These molecules enable indecipherable fluorescent patterns, enhancing document protection against counterfeiting.
Area of Science:
- Materials Science
- Organic Chemistry
- Polymer Science
Background:
- Conventional security inks on data pages are vulnerable to counterfeiting due to chemical deciphering.
- Polymer film data pages with embedded patterns offer a promising alternative to surface printing.
- Developing fluorophores for light-dose-controlled fluorescence within polymer matrices is crucial.
Purpose of the Study:
- To develop novel phototransformer molecules for advanced document security.
- To create indecipherable fluorescent patterns within polymer films for enhanced protection.
- To overcome limitations of conventional fluorophores, such as photobleaching and uncontrolled photoreactions.
Main Methods:
- Synthesis of diphenanthridinylfumaronitrile-based phototransformers (trans-D5).
- Investigating photoisomerization and photocyclization of D5 molecules during photopolymerization.
- Analyzing the rigidochromic behavior (emission shifts in rigid matrices) of trans-D5, cis-D5, and cyclo-D5.
Main Results:
- Developed D5 molecules that undergo stepwise redshifted solid-state emissions (trans-D5, cis-D5, cyclo-D5).
- Observed significant emission redshift (up to 172 nm) for cyclo-D5 in rigid polymer matrices.
- Demonstrated multicolor photochemical printing with a broad hue range (38 to 10 in Munsell color space) using D5 molecules.
Conclusions:
- Diphenanthridinylfumaronitrile-based phototransformers enable advanced, indecipherable fluorescent patterns in polymer films.
- The distinct rigidochromic properties of D5 molecules allow for precise control over multicolor photochemical printing.
- This approach offers superior document protection features compared to conventional security inks.
