Rapidly-Switching Photochromic Dyever3.0UV ON

Photochromism is the phenomenon which are accompanied by a color changes byisomerizes reversibly between two forms which have different absorption spectra byirradiation. Kanto Chemical has commercialized novel photochromic dyes which areoriginally designed and synthesized by Professor. Jiro ABE from Aoyama Gakuin
University.

■ Excellent photochromic characteristics.
１．Rapid Color-Switching
２．High Durability
３．Reactivity with Sunlight

Product Introduction
Photochromic materials change their colors upon irradiation with light. The main possible application ofphotochromic materials has been thought as use in optical data storages, hologram materials and light
modulators. There have been considerably researches and studies about photochromic compounds.
The 2 types of photochromic compounds, P-type and T-type. The photogenerated P-type compound
can be converted back to its initial structure by irradiation with a specific wavelength of light. Meanwhile,
the photogenerated T-type compound can be converted back to its initial structure thermally. However,
the thermal bleach reaction of photogenerated T-type compounds requires several minutes at room
temperature, and for practical use in certain applications, it demands a much faster speed in the returnto the initial state.
Kanto Chemical has commercialized pseudogem-Bis(diphenylimidazole) [2.2]paracyclophane andpseudogem-Bis(3,3,4,4’-tetramethoxydiphenylimidazole)[2.2]paracyclophane novel hexaarylbisimidazole(HABI) derivatives which have a paracyclophane structure so far. These novel compounds are originallydesigned and synthesized by Professor. Jiro ABE from Aoyama Gakuin University.
Kanto Chemical are pleased to announce to commercialize PY-1, PR-1 and PB-1 which have entirely
new backbone, and it changes color and bleaches upon the sunlight. It changes color and bleaches upon
the sunlight unlike the hexaarylbisimidazole (HABI) derivatives. They are colorless when dissolved intoluene, and change to Yellow(PY-1), Red(PR-1) or Blue(PB-1) upon the sunlight. After the blocking thesunlight, these color bleaches immediately.

PY-1, PR-1 and PB-1 dissolved in toluene change their color upon UV irradiation（365nm）,

PY-1（Yellow）

PR-1（Red）

PB-1（Blue）

Solvent: Toluene
UV irradiator：Keyence UV-400-5Concentration: 5.5×10 M
UV-LED(UV-50H) / UV-L6
Temperature: 20 ℃,
Quartz Cell: 1 mm ×10 mm× 40 mm,
Exciting light: （Wavelength） 365 nm, （Intensity） 400 mW/cm2

Transient vis‐NIR absorption spectra and Decay profile of PY‐1(Yellow).

UV ON

Figure 1
Transient vis-NIR absorption spectra intoluene after UV irradiation(365nm)

Concentration : 5.5×10-5 M
Exciting light : (Wavelength）365 nm（Intensity）400 mW/cm2
Temperature : 25 ℃

Figure 2
Absorbance change on the maximum
absorption wavelength in toluene before
and after UV irradiation (365nm)
Concentration : 5.5×10-5 M
Exciting light: (Wavelength） 365 nm（Intensity）400 mW/cm2
Temperature: 25 ℃
Irradiation time : 20 seconds

Transient vis‐NIR absorption spectra and Decay profile of PR‐1(Red).

UV ONTOPICS

Figure 3
Transient vis-NIR absorption spectra intoluene after UV irradiation(365nm)

Concentration : 5.5×10-5 M
Exciting light : (Wavelength）365 nm（Intensity）400 mW/cm2
Temperature : 25 ℃

Figure 4
Absorbance change on the maximum
absorption wavelength in toluene before
and after UV irradiation (365nm)
Concentration : 5.5×10-5 M
Exciting light: (Wavelength） 365 nm（Intensity）400 mW/cm2Temperature: 25 ℃
Irradiation time : 20 seconds

Transient vis‐NIR absorption spectra and Decay profile of PB‐1(Blue).

UV ON

Figure 5
Transient vis-NIR absorption spectra intoluene after UV irradiation(365nm)

Figure 6
Absorbance change on the maximum
absorption wavelength in toluene before
and after UV irradiation (365nm)

Concentration : 5.5×10-5 M
Exciting light : (Wavelength）365 nm（Intensity）400 mW/cm2
Temperature : 25 ℃

Concentration : 5.5×10-5 M
Exciting light: (Wavelength） 365 nm（Intensity）400 mW/cm2
Temperature: 25 ℃
Irradiation time : 20 seconds

Absorbance changes on the max. abs. wavelength PY‐1, PR‐1 and PB‐1 dissolved in toluene before and after UV irradiation (365nm)≪Comparison Absorbance changes≫
Half-life PY-1（25℃）
Half-life PR-1（25℃）
Half-life PB-1（25℃）

9 seconds
3 seconds
1.7 seconds

PY-1

PB-1

TOPICSFigure 7Transient vis-NIR absorption spectra intoluene after UV irradiation(365nm)
Concentration : 5.5×10-5 M
Exciting light : (Wavelength）365 nm（Intensity）400 mW/cm2
Temperature : 25 ℃

PR-1

Transient vis‐NIR absorption spectra and Decay profile of PY‐1 and PB‐1 dissolved in toluene.
PY-1 and PB-1 dissolved in toluene（1.6×10-4 M）, mix with 2:3 of PY1- and PB-1 dissolved
in toluene and evaluate it.

Figure 8 UV-Vis absorption spectra of mixture

Figure 9 Transient vis-NIR absorption
spectra pf mixture

Although the mixture shows the absorption spectra which is spread in the visible region of thespectrum under the photostationary state and changes color to dark brown, it shows the Yellow
for a while after the UV irradiation because of the difference of the both rates of heat of reactionof PY-1 and PB-1.
beforeJust after

10 s after

170 s after

Product List
ProductCat. No.

Package

PY-1

04780-68

100㎎

PR-1

04632-68

100㎎

PB-1

04609-68

100㎎

Relative products ‐ Cross‐linking hexaarylbisimidazole (HABI) derivatives ‐Kanto Chemical has commercialized hexaarylbisimidazole (HABI) derivatives which have a[2.2] paracyclophane structure which are originally designed and synthesized by Professor Jiro ABE from
Aoyama Gakuin Universtiy.
ProductCat. No.

Package04425-96

100㎎

04425-95

500㎎

04426-68

100㎎

04426-95

500㎎

pseudogem‐Bis(diphenylimidazole)[2.2]paracyclophane

pseudogem‐Bis(3,3’,4,4’‐tetramethoxydiphenylimidazole)[2.2]paracyclophane＜Reference＞
1) Y. Kishimoto, J. Abe, “A Fast Photochromic Molecule That Colors Only under UV Light”,
J. Am.Chem. Soc., 131, 4227 (2009)2) K. Mutoh, S. Hatano, J. Abe, “An Efficient Strategy for Enhancing the Photosensitivity of Photochromic[2.2]Paracyclophane-Bridged Imidazole Dimers” J. Photopolym. Sci. Technol., 23, 301 (2010)

Relative Products －Diarylethene －Kanto Chemical has commercialized a typical P‐type photochromic compound, diarylethene, which
was developed by Professor Irie from Rikkyo University(Past affiliation: Kyusyu University).
Product1,2-Bis(2-methylbenzo[b]thiophene-3-yl)
perfluorocyclopentene

Cat. No.

Package05058-63100㎎05058-96

100㎎● Please use the products listed in the catalog as reagents (chemicals used for testing or research purpose).
● Product information is subject to change without notice. For the latest information, please have a look at our website "Cica-Web".

KANTO CHEMICAL CO., INC.
REAGENT DIVISION

2-1, Nihonbashi Muromachi 2-chome, Chuo-ku, Tokyo, 103-0022, Japan
TEL: +81-0-6214-1092
E-mail : kanto-61@kanto.co.jp
Website: https://www.kanto.co.jp
OAG-03（201902）