Reversible Visualization for Synchrotron Radiation Using Photochromic Dye and Photostimulable Phosphor Composite Film

Abstract

The study reported herein is undertaken to visualize reversibly synchrotron radiation by using a composite film comprised of two components: a photochromic SP with the conversion characteristics of UV-to-visible color and PSP BaFCl:Eu 2+ particles with the conversion characteristics of X-rays-to-UV emission.

Radiation-induced colour changes in a spiropyran/BaFCl:Eu2+/polystyrene composite film and nonwoven fabric

“…The 381 nm peak was due to the electronic transition from the 4f 6 5d 1 ( 2 e g ) state of Eu 2+ to the 4f 7 ( 8 S 7/2 ) ground state, and the narrow peak at 360 nm could be attributed to the intraband transition from 4f 7 ( 6 P 7/2 ) to 4f 7 ( 8 S 7/2 ). 5 The intensity of the 381 nm peak decreased with an increase in the FWHM of the XRD peak, and its intensity decreased sharply when the FWHM of the XRD peak reached 8.51, corresponding to a pulverizing time of 4 h. The results indicate that the phosphor particles might have been damaged in the pulverization process, which would form surface defects or traps that quench the photoluminescence. Accordingly, the BaFCl:Eu 2+ phosphor powder without damage to the lattice should be used as the X-ray acceptor and the UV radiation source.…”

“…Therefore, finding a simple device, such as a ''colour dosimeter'', that can identify increased radiation through a colour change is strongly required. [1][2][3][4][5][6] Photochromism is defined as the reversible transformation of a chemical species between two forms via the absorption of electromagnetic radiation, where the two forms have different absorption spectra. 7 Spiropyrans are well-known photochromic compounds that have attracted significant interest for both their fundamental elucidation of photochemical reactions and their potential application to optical memory, 8,9 photo-optical switching, 10,11 and environmental sensors for temperature, 12 pH, 13 solvent polarity, 14 redox potential, 15 metal ions, 16 and mechanical force.…”

Leuco-Based Composite Resin Dosimeter Film

“…We developed a composite resin dosimeter (CRD), which is a kind of radiochromic dosimeter, using photoreversible spiropyran dye, 6-nitro BIPS, and BaFCl:Eu 2+ for detecting the low-dose radiation. − However, in this proposed CRD, the colored form of the photoreversible 6-nitro BIPS was thermally unstable, and there was a problem in preserving the recorded exposure doses. Fluoran leuco dyes are well-known chromogenic compounds used as color formers for pressure and thermosensitive data-recording systems.…”

A spiropyran-based X-ray sensitive fiber

“…11 Quite recently, we discovered that a spiropyran-based composite film with ultraviolet-emitting X-ray storage phosphor had the characteristic of indirectly detecting high-energy synchrotron radiation. 12 The reported paper implied that the spiropyrans can provide a new, highly sensitive radioactive ray indicator that applies X-ray storage phosphors based on an operation principle that is different from that of a conventional X-ray sensor by improving material, composition, and fashion.The study reported herein notes a fibrous structure with a high surface area to visualize radioactive rays from various angles, and is undertaken to visualize reversibe X-ray radiation by using a poly-(L-lactic acid) (PLLA) composite fiber containing photostimulable phosphor (PSP) BaFCl:Eu 2+ particles that are prepared and then dyed with the photochromic spiropyran dye (1,3,3-trimethylindolino-6 0 -nitrobenzopyrylospiran) (6-nitro BIPS).A spiropyran dye, 1 0 ,3 0 ,3 0 -trimethyl-6-nitrospiro[1(2H)-benzopyran-2,2 0 -indoline] (or 1,3,3-trimethylindolino-6 0 -nitrobenzopyrylospiran) (6-nitro BIPS) was used as the UV light-sensitive photoacceptor, and BaFCl:Eu 2+ was used as the UV-radiation source. All solvents (tetrachloroethylene, hexane, cyclohexane, acetone, and ethyl acetate) and the 6-nitro BIPS were purchased from Tokyo Kasei Co.…”

“…11 Quite recently, we discovered that a spiropyran-based composite film with ultraviolet-emitting X-ray storage phosphor had the characteristic of indirectly detecting high-energy synchrotron radiation. 12 The reported paper implied that the spiropyrans can provide a new, highly sensitive radioactive ray indicator that applies X-ray storage phosphors based on an operation principle that is different from that of a conventional X-ray sensor by improving material, composition, and fashion.…”