Photochromic compound, photochromic composition and photochromic display element using the same

Abstract

A photochromic display element comprising a photochromic layer 12 containing a 4,4′-bipyridine derivative as a photochromic compound intervined between a transparent substrate 11 placed at a front surface side and a substrate 13 placed at a rear surface side. When a light containing an infrared light having a wavelength of 830 nm is irradiated, the photochromic display element exhibits the absorbance spectrum within a visible light region is reversibly changed whereby the photochromic layer 12 is colored and bleached.

1 . A photochromic compound which sensitizes a wavelength region of not less than 700 nm or a specific infrared region to thereby exhibit absorbency at a visible region.  
     
     
         2 . The photochromic compound according to  claim 1 , which comprises a 4,4′-bipyridine derivative represented by the following formula (1):  
       
         
           
           
               
               
           
         
       
     
     
         3 . The photochromic compound according to  claim 1 , which comprises a 4,4′-bipyridine derivative represented by the following formula (2):  
       
         
           
           
               
               
           
         
       
       wherein R 1 , R 2 , R 3 , and R 4  may be the same or different from each other and each is a condensed aromatic hydrocarbon or a derivative thereof.  
     
     
         4 . The photochromic compound according to  claim 1 , which comprises a 4,4′-bipyridine derivative represented by the following formula (3):  
       
         
           
           
               
               
           
         
       
       wherein R 11  and R 12 , may be the same or different from each other and each is an alkyl group having 1 to 10 carbon atoms or a derivative thereof; and X −  is selected from among Cl − , BF 4   − , PF 6   − , AsF 6   − , ClO 4   − , and NO 3   − .  
     
     
         5 . A photochromic composition comprising a solution having the photochromic compound according to  claim 1  dissolved in one solvent or a mixed solvent selected from among dimethylformamide (DMF), dimethylacetamide, propylene carbonate, acetonitrile, gamma-butyllactone, and butanol.  
     
     
         6 . A photochromic film comprising a film having the photochromic compound according to  claim 1  dispersed therein.  
     
     
         7 . A photochromic composition at least comprising the photochromic compound according to  claim 1  and a ultraviolet absorber, which absorbs a ultraviolet light.  
     
     
         8 . A functional element, comprising 
 a photochromic which sensitizes a wavelength of not less than 700 nm or a specific wavelength within an infrared region, and which exhibits absorbance within a visible region, and    a light source which has an energy strength at a wavelength region of not less than 700 nm or a specific wavelength within an infrared region enough for being sensitized by the photochromic compound,    wherein a photochromic phenomenon, which sensitizes a wavelength of not less than 700 nm or a specific wavelength within an infrared region, and which exhibits absorbance within a visible region, is utilized.    
     
     
         9 . The functional element according to  claim 8 , which possesses a ultraviolet shielding member, which shield an incident ultraviolet light entering in the functional element.  
     
     
         10 . The functional element according to  claim 8 , wherein said photochromic layer containing the photochromic compound at least comprises a ultraviolet absorber, which absorber a ultraviolet light.  
     
     
         11 . The functional element according to  claim 8 , which is a photochromic display element.  
     
     
         12 . The functional element according to  claim 8 , which is an anti-glare mirror.