The development of blue long-lasting phosphorescent materials for fibers

The main raw material for preparing blue light night glow fibers is the rare earth long-lasting phosphorescent material that can emit blue light. The research fields of blue light long-lasting phosphorescent materials include the metal sulfide system, the aluminum oxide system, and the silicate system. In 1866, French chemist Theodore Sidot prepared ZnS-based sulfide phosphorescent materials, which belong to the first generation of long-lasting phosphorescent materials. Since the 1920s, people have begun to develop blue light sulfide system long-lasting phosphorescent materials, such as the addition of a small amount of Ag can produce blue light, and adding halide flux agents can obtain blue self-luminous materials ZnS: CI-, and then blue light phosphorescent materials such as CAS: Bi[3s] and CaSrS: Bi[²*] were also developed. However, the blue light phosphorescent materials of the metal sulfide system have the characteristics of low light emission brightness, short afterglow time, and unstable chemical properties, which limits the application range of blue light night glow fibers prepared from metal sulfide. The alkaline earth activated aluminum oxide system phosphorescent materials are the second generation of long-lasting phosphorescent materials that have been studied the most and have the best luminescence performance. PALILA et al. first discovered the afterglow phenomenon of SrAl,O.:Eu+ in 1986, but this phosphorescent material has the disadvantages of a single luminescent color and lack of light colors in the long-wave and short-wave bands. Later, MAL,O, :EU²+ (M: CA, Sr, Ba) was reported by BJIaHK et al. in 1975. In 1993, after Japanese scholars conducted detailed research on the long-lasting phosphorescence characteristics of alkaline earth aluminum oxide system SrAlO. :Eu²+ phosphorescent materials, foreign researchers reported on alkaline earth aluminum oxide system phosphorescent materials continuously. In recent years, foreign researchers have reported rare earth activated CaALO. based and BaAL,O, based blue light phosphorescent materials. In 2008, Korean researcher H. Ryu et al. synthesized different activator content CaAl,O,:Eu, Cr blue light phosphorescent materials by high-temperature solid-phase method, and deeply explored its excitation emission spectral performance. The results showed that the maximum emission peak of this calcium aluminum phosphorescent material was located at 440 nm. In 2009, H. Ryu et al. also synthesized CaAl,O, :Eu, Dy blue light phosphorescent materials, by changing the content of activators EU²+ and Dy+, to study the optimal parameters for luminescence performance. In 2014, A. H. Wakoa et al. doped Eu²+ and ND’+ into CaAl.O, based, and used the sol-gel method to synthesize a blue light phosphorescent material with an emission spectrum at 440 nm, focusing on exploring the luminescence mechanism of the phosphorescent material and clarifying the content of the flux agent (boric acid) required for the optimal afterglow performance. Moreover, since the 20th century, a large number of researchers have begun to report blue light materials based on BAAlO, and BaAL,O, : Eu²+, Re²+ (RE²+ = Dy²+, Nd²+, GD²+, Sm²+, Ce²+, Er²+, Pr+, TB+) have emerged successively. Among them, BAAL,O. : EU+, ER+ has the highest luminescent brightness and the longest afterglow time. The blue light phosphorescent materials based on CaAL,O, and BaAL,O, have slightly inferior luminescent brightness and afterglow time compared to the rare earth activated SrALO, based yellow-green light phosphorescent materials, thus limiting the application of blue light long-lasting phosphorescent materials in textile fibers.