°Ƹßľļ2Ƈéªċ1@CǮďƗĮľŬ¢ahLY2Ĭ¡ƀöÜâĬ¡ƀĮľ¢NxRbyeRYųŽ[z]|ãǌµŇŰǴǳOLED ťŬ¢ĲĦ2òǙ OLEDǰĮľ ELǱ3ľƗ§ǠD&ģ´ nm 2ÛôƘA0CƹƠƘô1Ǣß.n|wǰŀàǱGǞĻ.ǟĻA$D%Dň£ǰinjectionǱ Įľô¥GƾǃD&Ǣß.
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DC.3-1 1950 üAŢưŭ0ƕê1@),ýűAD,& 1990 ü¨
Ǫ13 ƃƖA>TbRovzƮî 3,4) Eu Ʈî 5) Tb Ʈî 6)ƄGĺƪ&
77K -2ĻŐ-2Ŭ¢?ơ¢ahLY@B>ƝŬ¢±ş1Ũ:),& $2Ĉ 1990 ü2Ĉ¶1, PtOEP7)? Ir(ppy)38,9)1ƢDC@1 Pt ? Ir Ƅ2Ǔºß±ĵ1@BçŐ1,ăvz¢Ŭ¢Gŵ ĮľǕó³ÃŚGŬ¢ĲĦ1ťC.- 89 100%2¥Ǐ EL Ŭ¢±şǰIQEǱŠæ&ǰƂ 2 Ǳ ŠÏ Ir ǖ3§ßļǇ2ĬǍ³ä ƒƛ.ƷƛǩÓ1CæťahLY1,ûýť
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2012 ü Ē 2ųŽSw|k3 ơ¢ĲĦ vz¢ĲĦ1ĿƂ 3 2Ŭ¢ĲĦ.
, ǮďƗ0řŉď³ǉĀơ¢(Thermally Activated Delayed Fluorescence, TADF)ĲĦ
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ǁĜ"C.- ~ǓǨ°ƸŜĐG}ǓǨ°ƸŜĐ6J_kVzh|Xtz" Ĭƌ
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0)&2-C 11)

– 1 –

100

Ir(ppy)3N
Ir

N

4CzIPNN

3rd-G

Internal ELefficiency (%)

TADF

2nd-G
Phosphorescence

75

NN

PtOEP

PIC-TRZ

PtNN

50
NO0O
AlN

25

62.5%

TTA
Guest-hostdoping system

NO

Anthracene
derivatives

p-n type
Anthracene
Single Crystal

1st -G
Fluorescence

Double hetero

SnF2 (OEP)

Keto-Coumarin
Low temp phos.

1950

1960

1970

1980

1990

2000

2010

2020

Year
Í 1ǸOLED ťŬ¢ĲĦ2ǈò3 ơ¢ǰƂ}Ǳ BH¢ǰƂǱ TADFǰƂ~Ǳ1§Ǭ-C Ƃ}2ơ¢ĲĦ3 TTA ĲĦ6.ǈò,CǵǳTADF ĲĦ2§ßƫƩÍǵ1ǢŊ°Ƹ1C§ß2NfwQ|ŜĐÍ. TADF ǊźGŵ- Ĭ°Ƹ~ǓǨŜĐǰT1Ǳ Ĭ°Ƹ}ǓǨŜĐǰS1Ǳ¼5ÔþŜĐǰS0Ǳ2 3 *2Nfw
Q|xlw TADF 1Ǜ CÖÃGƕC ¢°Ƹ2ÖÃ TADF 3}ǓǨ°ƸŜĐ
A~ǓǨ°ƸŜĐ6ƈǚøǊźGƎ,Ýŉ&°Ƹß¦5 T1 S1 ǄǨǚøǰReverse Intersystem CrossingǲRISCǱGǅ, S1 œ1ǎŹ $D1Ƒ S1S0ƿíÝŉǰRadiative decayǱ2ǊźA0C ǢŊ°Ƹ2ÖÃ3 }ǓǨA2ÝŉǊ
ź1¯, ŮĜ Ǣß.n|w2¦ƏÃ-Ťđ&~ǓǨ°ƸßJ_kVzh|Xt
z1è C.10C - RISC (T1S1)3ǤġíÝŉǰT1S0Ǳ
ǰnonradiative
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T1S0 ǎŹ2ǤġíÝŉǆÿǰknr'Ǳ@B>ǆ CčƥCǰkRISC > knr'Ǳ }ĨS1S0 ġíÝŉ3 S1S0 ǤġíÝŉ.Ɓ C&= S1S0 ġíÝŉG ¡"C&=13 $2ǆÿǰkrǱG S1S0 ǤġíÝŉǆÿǰknrǱ@B>ǆ CčƥC D
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𝐾𝐾 = ∬ 𝜙𝜙% (1)𝜙𝜙) (2)+,-.

𝜙𝜙% (2)𝜙𝜙) (1) 𝑑𝑑𝜏𝜏+ 𝑑𝑑𝑑𝑑1 （式１）}Ĩ-§ß1Ŭ¢ľƗG C&=13ǲĚ²ßăÿ(f)GÜ3ǎŹ½Ļßr|qzb(µ)21Ń C(ā 2)𝜇𝜇 = ∬ 𝜙𝜙3454 |𝑒𝑒𝑒𝑒|𝜙𝜙%)54 𝑑𝑑𝑑𝑑

CčƥBǲf （式２）A1 3 HOMO . LUMO 2žǚŭ0Ǔ0B1Ń C&= ăŬ¢ăÿGĊC&=13Ü0 HOMO . LUMO 2Ƽǋ2Ǔ0Bčƥ.DC 11) @), ·1ESTGï C'-3 TADF 2Ŭ¢±ş3Ä0 $D3 HOMO . LUMO GǊ
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ė&" ï0EST 1¯,Ü0Gſ"CčƥC ÍǶ13ǲŠÏ:-ÕÇD,& TADF §ß2EST . kRISC 2ǛGŵ,C EST 2Ŏð..>1kRISC 2ÄƧőDC Ĭ>ǆ TS ǎŹǆÿ-> İ' 1 µ s 1Ũ:),
C }ƚ1 kRISC 32Ǜā-ADC 1)
DE𝑘𝑘:;<= = 𝐴𝐴 exp (− H FG) ǰāǶǱJIā@BǲkRISC GÄ"C&=13 2 *2Ǔƥ0ËßáÏ C.FC Ƃ}
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Ĭǁ2ųŽAĪA.0),&Pre-factor ADESTÍǶǸǄƈǚøǆÿ(kRISC).DEST 2ůǛǛǮďƗ0 TADF §ßGƫƩ C&=13 D:-1 D-A ļǇÔıļǇ-C.
Gǂ7,& $DÚ2§ßǭķ->ǮďƗ0 TADF śď2ŬŠÀƗ-C.
ĪA1D,& 2014 ü13 D-A ǭķAÚDC n-p*ƈ26k]XzƮîTADF śďGŵ .ÕÇD& 15) UYb−nYbƠƘ1C PLQY 3 30ǯźÿ
1Ũ:),3C>22 ǉĀơ¢ìÉǹ250ns źÿ2Ļ=,ŲGŵ,C A1 Ĭǁ-3 ũõA1@), charge resonance ±ĵG©ť&Ǭ2 HOMOLUMO §Ǡľļ2§ßĝĸD ǮďƗ0 TADF §ßÕÇD,C 16) DA2
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Ùx|W|¢Œ.,Ǥú1Ü0ÀƗďįćD,C İ'ǢŊ°Ƹ1@CĮľ¶îx|W|3æŠD,A! ęēŭƯǫ.,ĮľNxRbyeRY2łD&jyz`KJ-C æŠGǜ<Ưǫ2}*., ǢƜ¦ƏÃ1@B 75ǯ2®Ã-Ťđ C~ǓǨ°Ƹß2áÏC0F( ĮľƛƊ§ß1ŤđDC~ǓǨ°Ƹß
2áÏ1@B }ǓǨ-~ǓǨ°Ƹßůť1@CŬ¢±ş2?~ǓǨ°ƸŜĐÆ¾1@C¢ĠÝŤC.Ü0Êǫ-C $2&=ĉĴ3 ǒƊƄ2~ǓǨÝŉ­Gť ~ǓǨ°ƸßG ŘƿíÝŉ "C.1@B ~ǓǨ°Ƹßéÿ2ĕªÍAD,& 18) 0A ǢŊ°ƸGĘÄ&ÖÃ 2ēŪ1Ô+. $2°ƸßŤđ±ş3Ǯ 25ǯ1Ũ:C $- T1 A S1 62 RISC Ǌź1@B ŤđD&~ǓǨ°ƸßG 100%2®Ã-}ǓǨ6.ǎŹ" $2 TADF §ß-Ťđ&°ƸßNfwQ|Gx|W|ƛƊ6.NfwQ|Ź²"Cħ&0Ŭ¢ľļGĝĸ,C 19) ıľļ1@B ǢŊ°Ƹ1,x|W|ƛƊ-°ƸßŤđ±ş 100%ǌđÀƗ.0C&= ºŢŭ1x|W|ŬĚ1čƥ0ǢŊéÿ3 ĉĴ2Ĕņ.Ńƽ, 1/4.0C.įćDC Šīŗ-3 RISC ǆÿ~106 s–1 źÿ.ǉ x|W|ŬĚ
1è-C~ǓǨ°Ƹß2ŖÿǤú1ï.Êǫŗ-C :& TADF §ßƙƻx|W|ŬĚľƗGĮ,C§ß>Ʀ*),B Ĉ2ħĲĦ2òǙįćÍǷǸýCĮľŬ¢§ß2°ƸìÉ2īǚYT|w.ÂŻahLYĎť

– 5 –DC 20) ĬĈ1 Ŭ¢§ß2°ƸìÉ-ĤŢ&ĮľŬ¢§ßGÍǷ1ŵŬ¢ì
É3 §ßǭķGÙ³"C.- ns AģŸǚ1ŏ),ý),C ŲìÉ2ơ¢§ß3Įľx|W|1Ǎ,B µs O|^|2ìÉGĮ CŬ¢§ß3 Ir ǖ? TADF
1ƢDC@1}ǓǨ.~ǓǨŜĐ2ōÃŤ,B Ǣń°Ƹ-Ǯ±ş0Ŭ¢ĊADC }Ĩ- çŐ-2řÝŉŜĐG´§1ĕª C.- ÎƠƘ1,
3 çŐBH¢?cd|.JR[k]|2ƍ;ÃF"1@CǢƜ§ǠŜĐG©ť C.
-1 īǚ1ŏCǘìÉ2çŐƞ¢ahLY>ÀƗ.0)& 21) Ĉ Ľ 0īǚYT|w1@CĮľŬ¢§ß2ŉƺįćDCƱǀĩǧA TADF 2ųŽ1,ŌƲưGǦ,CÜ OPERA 2qzh|Kyulux 2qzh|¼5ǐÜâ2ĹĢě1 2ÖGB,ŌŶŦ:(Ķ)»ƕĥŞ1) N. J. Turro, “Modern Molecular Photochemistry” University Science Books, (1991).
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