Bright and efficient organic electroluminescent(EL)devices have attracted considerable interest due to their potential application to flat panel display.To realized full color display applications

the three elemental colors of red

green

and blue emitters with sufficiently high luminous and color purity are necessary.After the last two decades of intensive research

a number of green and blue emitters with high luminance

high efficiency

saturated emission

and practical lifetimes have been developed.However

the corresponding development of the red emitters lags significantly behind that for the other two primary colors.Doping a red dye into a suitable host makes most high-performance of red EL devices.Nevertheless

the low efficiency at high doping concentration is due to the concentration quenching effect

which is common in fluorescence dopants.This problem can be avoided by using host red emitting materials

which can be used as emitting layer as well as hole or electron transport layer.In this paper

a novel red luminescent material N

N-bis-[4-[2-(4-dicyanomethylene-6-methyl-4H-pyran-2-yl)ethylene]phenyl]

aniline(BDCM)with two electron-acceptor moieties(4-dicyanomethylene)pyran and an electron-donor moiety triphenylamine for application in organic EL devices was reported.The resultant compound has a sterically well-hindered structure and a high fluorescence yield.Its photoluminescence(PL)of this compound in solid film and EL have been studied.Based on its intense sterically hindered structure

the pure BDCM film prepared shows a bright red PL emission.The EL device with a structure of indium tin oxide(ITO)/copper phthalocyanine(CuPc)/1

3-diphenyl-5-(1-phenanthreneyl)-2-pyrazoline(DPPP)/BDCM/Mg:Ag shows a bright red emission and a brightness of 582cd/m

2

at a driving voltage of 19V.And it can be found that CIE chromaticity coordinates of the device are nearly unchanged with increasing current density.As expected

the rigidity and non-planar structure of triphenylamine moiety offers BDCM a sterically well-hindered feature

and consequently an excellent pure red emission is obtained even for the pure BDCM.Further

the presence of two electron-acceptor moieties increase the electron affinity of BDCM

and as a result

grant the BDCM efficient electron injection and transport abilities.The combination of above advantages

as the result of incorporating triphenylamiline and two(4-dicyanomethylene)pyrane moieties into one molecule make BDCM serve as host red emitter possible.aniline(BDCM)with two electron-acceptor moieties(4-dicyanomethylene)pyran and an electron-donor moiety triphenylamine for application in organic EL devices was reported.The resultant compound has a sterically well-hindered structure and a high fluorescence yield.Its photoluminescence(PL)of this compound in solid film and EL have been studied.Based on its intense sterically hindered structure

the pure BDCM film prepared shows a bright red PL emission.The EL device with a structure of indium tin oxide(ITO)/copper phthalocyanine(CuPc)/1

3-diphenyl-5-(1-phenanthreneyl)-2-pyrazoline(DPPP)/BDCM/Mg:Ag shows a bright red emission and a brightness of 582cd/m

2

at a driving voltage of 19V.And it can be found that CIE chromaticity coordinates of the device are nearly unchanged with increasing current density.As expected

the rigidity and non-planar structure of triphenylamine moiety offers BDCM a sterically well-hindered feature

and consequently an excellent pure red emission is obtained even for the pure BDCM.Further

the presence of two electron-acceptor moieties increase the electron affinity of BDCM

and as a result

grant the BDCM efficient electron injection and transport abilities.The combination of above advantages

as the result of incorporating triphenylamiline and two(4-dicyanomethylene)pyrane moieties into one molecule make BDCM serve as host red emitter possible.