Preparation and properties of dual-wavelength excitable fluorescent Lyocell fibers and their applications in papermaking

Abstract

Two kinds of dual-wavelength excitable fluorescent Lyocell fibers, which can be excited by short-wavelength UV/IR or long-wavelength UV/IR radiation, were prepared by dry-jet wet spinning. These fluorescent Lyocell fibers can emit two different fluorescence wavelengths at two different excitation wavelengths, exhibiting double anti-counterfeiting functions, thereby providing higher security. SEM-EDX analysis showed the uniform phosphors distribution in Lyocell fibers. The fluorescent Lyocell fibers were mixed into pulp for papermaking. Addition of dual-wavelength excitable fluorescent Lyocell fibers had no influence on brightness and opacity of papers, and the mechanical properties of papers were similar or even higher than paper with addition of pure Lyocell fibers, although the introduction of phosphors decreased the mechanical properties of Lyocell fibers slightly. Our results proved that dual-wavelength excitable fluorescent Lyocell fibers can be used not only in textile fibers, but also in papermaking to develop various security paper products.