Long-Term Functional Stability of Organic and Inorganic Modified Luminescent Lyocell Fibers for Security Applications

Area of Science:

• Materials Science
• Textile Engineering
• Optics

Background:

• Cellulose-based fibers offer unique optical properties for anti-counterfeiting.
• Luminescent materials integrated into fibers can create covert authentication markers.
• Lyocell fibers are a sustainable cellulose source for advanced material applications.

Purpose of the Study:

• To assess the functional durability of luminescent Lyocell fibers under simulated environmental stress.
• To investigate the impact of accelerated aging on the mechanical and luminescent properties of modified fibers.
• To evaluate the potential of these fibers as covert security elements in authentication systems.

Main Methods:

• Lyocell fibers were modified with inorganic and organic luminescent compounds.
• Fibers underwent accelerated aging using a xenon lamp to simulate environmental exposure.
• Mechanical properties (tensile strength, elongation at break) were measured before and after aging.
• Luminescent behavior was analyzed using spectroscopic methods to assess changes in emission.

Main Results:

• Accelerated aging reduced tensile strength and elongation at break in all fiber variants.
• The extent of mechanical property degradation varied depending on the type of luminescent modifier used.
• Despite reduced emission intensity, the characteristic luminescent responses remained detectable after aging.
• The immobilization of luminophores within the cellulose matrix contributed to observed stability.

Conclusions:

• Luminescent Lyocell fibers demonstrate retained identification potential after simulated environmental exposure.
• These modified fibers are promising candidates for covert security elements in anti-counterfeiting applications.
• Further research is needed on long-term stability and photophysical properties under prolonged environmental stress.