ORGANIC ELECTROLUMINESCENT DEVICE EMITTING GREEN LIGHT

1 - 15 . (canceled)

16 . An organic electroluminescent device comprising one or more light-emitting layers B, each comprising independently of each other:

(i) at least one host material H B , which has a lowermost excited singlet state energy level E(S1 H ) and a lowermost excited triplet state energy level E(T1 H );

(ii) at least one thermally activated delayed fluorescence (TADF) material E B , which has a lowermost excited singlet state energy level E(S1 E ) and a lowermost excited triplet state energy level E(T1 E ); and

(iii) at least one small full width at half maximum (FWHM) emitter S B , which has a lowermost excited singlet state energy level E(S1 S ) and a lowermost excited triplet state energy level E(T1 S ),

wherein each E B transfers energy to at least one S B and each S B emits light with an emission maximum between 500 nm to 560 nm, wherein the relations expressed by the following formulas (1) to (5) apply:

E ( S 1 H )> E ( S 1 E )  (1)

E ( S 1 H )> E ( S 1 S )  (2)

E ( S 1 E )> E ( S 1 S )  (3)

E ( T 1 H )> E ( T 1 S )  (4)

E ( T 1 H )> E ( T 1 E )  (5);

wherein at least one small full width at half maximum (FWHM) emitter S B is a boron containing emitter.

17 . The organic electroluminescent device according to claim 16 , wherein a TADF material E B exhibits a ΔE ST value, which corresponds to the energy difference between the lowermost excited singlet state S1 E and the lowermost excited triplet state T1 E , of less than 0.4 eV.

18 . The organic electroluminescent device according to claim 16 , wherein the at least one small FWHM emitter S B has an emission spectrum, which exhibits a full width at half maximum (FWHM) of less than or equal to 0.25 eV.

19 . The organic electroluminescent device according to claim 16 , wherein the at least one thermally activated delayed fluorescence (TADF) material E B has an emission maximum λ max (D) in the wavelength range of 500 nm to 560 nm.

20 . The organic electroluminescent device according to claim 16 , wherein the at least one thermally activated delayed fluorescence (TADF) material E B has a highest occupied molecular orbital HOMO(E B ) having an energy E HOMO (E B ) according to −6.0 eV≤E HOMO (E B )≤−5.8 S eV.

21 . The organic electroluminescent device according to claim 16 , wherein the at least one thermally activated delayed fluorescence (TADF) material E B has a structure represented by any of the formulas E B -I-1a, E B -I-2a, E B -I-3a, E B -I-4a, E B -I-5a, E B -I-6a, E B -I-7, and E B -I-8,

wherein

Y 1 is at each occurrence nitrogen (N) or CH, and at least one Y 1 is N;

m is at each occurrence independently of each other 0, 1, or 2;

n is at each occurrence independently of each other 0, 1, or 2;

p is at each occurrence independently of each other 0, 1, or 2;

q is at each occurrence independently of each other 0, 1, or 2;

X 2 is at each occurrence independently of each other selected from the group consisting of Ar EWG , CN, and CF 3 ;

Ar EWG is at each occurrence independently of each other represented by a structure according to any of the formulas Ar EWG -I, Ar EWG -II, Ar EWG -III, Ar EWG -IV, Ar EWG -V, Ar EWG -VI, Ar EWG -VII, Ar EWG -VIII, Ar EWG -IX, Ar EWG -X, Ar EWG -XI, Ar EWG -XII, Ar EWG -XIII, and Ar EWG -XIV,

which are bonded to the core structure via the position marked by the dashed line;

R 21 is at each occurrence independently of each other selected from the group consisting of CN and CF 3 ;

Z 3 is at each occurrence independently of each other selected from the group consisting of a direct bond, CR 9 R 10 , C═CR 9 R 10 , C═O, C═NR 9 , NR 9 , O, SiR 9 R 10 , S, S(O), and S(O) 2 ;

R 8 is at each occurrence independently of each other selected from the group consisting of: hydrogen, deuterium, CN, CF 3 ,

C 1 -C 5 -alkyl, wherein one or more hydrogen atoms are optionally substituted by deuterium,

C 6 -C 18 -aryl, which is optionally substituted with one or more substituents R 11 , and

C 3 -C 17 -heteroaryl, which is optionally substituted with one or more substituents R 11 ;

R b , R c , R d , R 9 , and R 10 are at each occurrence independently of each other selected from the group consisting of: hydrogen, deuterium, N(R 12 ) 2 , OR 12 , Si(R 12 ) 3 , B(OR 12 ) 2 , OSO 2 R 12 , CF 3 , CN, F, Br, I,

C 1 -C 40 -alkyl, which is optionally substituted with one or more substituents R 12 and

wherein one or more non-adjacent CH 2 -groups are optionally C═Se, C═NR 12 , P(═O)(R 12 ), SO, SO 2 , NR 12 , O, S, or CONR 12 ,

C 1 -C 40 -alkoxy, which is optionally substituted with one or more substituents R 12 and wherein one or more non-adjacent CH 2 -groups are optionally substituted by R 12 C═CR 12 , C≡C, Si(R 12 ) 2 , Sn(R 12 ) 2 , C═O, C═S, C═Se, C═NR 12 , P(═O)(R 12 ), SO, SO 2 , NR 12 , O, S, or CONR 12 ,

C 1 -C 40 -thioalkoxy, which is optionally substituted with one or more substituents R 12 and wherein one or more non-adjacent CH 2 -groups are optionally substituted by R 12 C═CR 12 , C≡C, Si(R 12 ) 2 , Ge(R 12 ) 2 , Sn(R 12 ) 2 , C═O, C═S, C═Se, C═NR 12 , P(═O)(R 12 ), SO, SO 2 , NR 12 , O, S, or CONR 12 ,

C 2 -C 40 -alkenyl, which is optionally substituted with one or more substituents R 12 and wherein one or more non-adjacent CH 2 -groups are optionally substituted by R 12 C═CR 12 , C≡C, Si(R 12 ) 2 , Ge(R 12 ) 2 , Sn(R 12 ) 2 , C═O, C═S, C═Se, C═NR 12 , P(═O)(R 12 ), SO, SO 2 , NR 12 , O, S, or CONR 12 ,

C 2 -C 40 -alkynyl, which is optionally substituted with one or more substituents R 12 and wherein one or more non-adjacent CH 2 -groups are optionally substituted by R 12 C═CR 12 , C≡C, Si(R 12 ) 2 , Ge(R 12 ) 2 , Sn(R 12 ) 2 , C═O, C═S, C═Se, C═NR 12 , P(═O)(R 12 ), SO, SO 2 , NR 12 , O, S, or CONR 12 ,

C 6 -C 60 -aryl, which is optionally substituted with one or more substituents R 12 , and

C 3 -C 57 -heteroaryl, which is optionally substituted with one or more substituents R 12 ;

R 11 is at each occurrence independently of each other selected from the group consisting of: hydrogen, deuterium, Me, i Pr, t Bu, CN, CF 3 , and phenyl, which is optionally substituted with one or more substituents independently of each other selected from the group consisting of Me, i Pr, t Bu, CN, CF 3 , and Ph;

R 12 is at each occurrence independently of each other selected from the group consisting of: hydrogen, deuterium, OPh, CF 3 , CN, F,

C 1 -C 5 -alkyl, wherein one or more hydrogen atoms are optionally, independently from each other substituted by deuterium, CN, CF 3 , or F,

C 1 -C 5 -alkoxy, wherein one or more hydrogen atoms are optionally, independently from each other substituted by deuterium, CN, CF 3 , or F,

C 1 -C 5 -thioalkoxy, wherein one or more hydrogen atoms are optionally, independently from each other substituted by deuterium, CN, CF 3 , or F,

C 2 -C 5 -alkenyl, wherein one or more hydrogen atoms are optionally, independently from each other substituted by deuterium, CN, CF 3 , or F,

C 2 -C 5 -alkynyl, wherein one or more hydrogen atoms are optionally, independently from each other substituted by deuterium, CN, CF 3 , or F,

C 6 -C 15 -aryl, which is optionally substituted with one or more C 1 -C 5 -alkyl substituents,

C 3 -C 17 -heteroaryl, which is optionally substituted with one or more C 1 -C 5 -alkyl substituents,

N(C 6 -C 15 -aryl) 2 ,

N(C 3 -C 17 -heteroaryl) 2 ,

N(C 3 -C 17 -heteroaryl)(C 6 -C 15 -aryl), and

an aliphatic cyclic amino group comprising 5 to 8 carbon atoms;

R 13 is at each occurrence independently of each other selected from the group consisting of: hydrogen, deuterium, CN, CF 3 , Ar EWG ,

C 1 -C 5 -alkyl, wherein one or more hydrogen atoms are optionally substituted by deuterium, and

C 6 -C 15 -aryl, which is optionally substituted with one or more substituents independently of each other selected from deuterium, C 1 -C 5 -alkyl groups, and C 6 -C 15 -aryl groups; and

R 14 and R 15 are at each occurrence independently of each other selected from the group consisting of C—Ar EWG and CR Q2 ;

R 16 is at each occurrence independently of each other selected from the group consisting of CR 6 , C-Ar EWG , and CR Q2 ;

R Q2 is at is at each occurrence independently of each other selected from the group consisting of: hydrogen, deuterium, Me, i Pr, tBu, CN, CF 3 , Ph, and

carbazolyl, which is optionally substituted with one or more substituents independently from each other selected from the group consisting of Me, i Pr, t Bu, CN, CF 3 , Ph, and N(Ph) 2 ;

wherein, optionally, any adjacent substituents R b , R c , R d , R 9 , and R 10 independently of each other form a mono- or polycyclic, aliphatic, aromatic and/or benzo-fused ring system;

wherein one or more hydrogen atoms of the optionally so formed ring system may be substituted by R 12 ;

wherein not more than two groups R 13 are CN, CF 3 or Ar EWG ; and

wherein: 1≤(m+p) and

1≤(n+q).

22 . The organic electroluminescent device according to claim 16 , wherein the at least one small FWHM emitters S B comprises or consists of a structure according to formula S B -I:

wherein B is boron,

Ar 1 , Ar 2 , and Ar 3 are at each occurrence independently of each other selected from the group consisting of an aromatic ring and a heteroaromatic ring, and Ar 1 , Ar 2 , and Ar 3 may optionally be linked to each other to form one or more additional rings.

23 . The organic electroluminescent device according to claim 16 , wherein the at least one small FWHM emitters S B comprises or consists of a structure of formula S B -III-3a:

wherein R VI , R VII , R VIII , R IX , R X , R XI , R XII , R XIII , R XIV , R XV , R XVI , R XVII , R XVIII , R XIX , R XX , R XXI , R XXII , and R XXIII are independently of each other selected from the group consisting of: hydrogen, deuterium, N(R 21 ) 2 , OR 21 , SR 21 , Si(R 21 ) 3 , B(OR 21 ) 2 , OSO 2 R 21 , CF 3 , CN, halogen,

C 1 -C 40 -alkyl, which is optionally substituted with one or more substituents R 21 and wherein one or more non-adjacent CH 2 -groups are optionally substituted by R 21 C═CR 21 , C≡C, Si(R 21 ) 2 , Ge(R 21 ) 2 , Sn(R 21 ) 2 , C═O, C═S, C═Se, C═NR 21 , P(═O)(R 21 ), SO, SO 2 , NR 21 , O, S, or CONR 21 ,

C 1 -C 40 -alkoxy, which is optionally substituted with one or more substituents R 21 and wherein one or more non-adjacent CH 2 -groups are optionally substituted by R 21 C═CR 21 , C≡C, Si(R 21 ) 2 , Ge(R 21 ) 2 , Sn(R 21 ) 2 , C═O, C═S, C═Se, C═NR 21 , P(═O)(R 21 ), SO, SO 2 , NR 21 , O, S, or CONR 21 ,

C 1 -C 40 -thioalkoxy, which is optionally substituted with one or more substituents R 21 and wherein one or more non-adjacent CH 2 -groups are optionally substituted by R 21 C═CR 21 , C≡C, Si(R 21 ) 2 , Ge(R 21 ) 2 , Sn(R 21 ) 2 , C═O, C═S, C═Se, C═NR 21 , P(═O)(R 21 ), SO, SO 2 , NR 21 , O, S, or CONR 21 ,

C 2 -C 40 -alkenyl, which is optionally substituted with one or more substituents R 21 and wherein one or more non-adjacent CH 2 -groups are optionally substituted by R 21 C═CR 21 , C≡C, Si(R 21 ) 2 , Ge(R 21 ) 2 , Sn(R 21 ) 2 , C═O, C═S, C═Se, C═NR 21 , P(═O)(R 21 ), SO, SO 2 , NR 21 , O, S, or CONR 21 ,

C 2 -C 40 -alkynyl, which is optionally substituted with one or more substituents R 21 and wherein one or more non-adjacent CH 2 -groups are optionally substituted by R 21 C═CR 21 , C≡C, Si(R 21 ) 2 , Ge(R 21 ) 2 , Sn(R 21 ) 2 , C═O, C═S, C═Se, C═NR 21 , P(═O)(R 21 ), SO, SO 2 , NR 21 , O, S, or CONR 21 ,

C 6 -C 60 -aryl, which is optionally substituted with one or more substituents R 21 , and

C 3 -C 57 -heteroaryl, which is optionally substituted with one or more substituents R 21 ;

wherein optionally one or more pair of adjacent groups R VI and R VII , R VII and R VIII , R VIII and R IX , R X and R XI , R XI and R XII , R XII and R XIII , R XIV and R XV , R XV and R XVI , R XVI and R XVII , R XVII and R XVIII , R XIX and R XX , R XX and R XXI , R XXI and R XXII , and R XXII and R XXIII forms an aromatic ring system which is fused to the adjacent benzene ring a, b, c, or d of general formula S B -III-3a and which is optionally substituted with one or more substituents R 21 ;

wherein optionally one or both pairs R VI and R XXIII , and R XIII and R XIV are joined to form a group Z 4 which is at each occurrence independently of each other selected from the group consisting of: a direct bond, CR 22 R 23 , C═CR 22 R 23 , C═O, C═NR 22 , NR 22 , O, SiR 22 R 23 , S, S(O), and S(O) 2 ;

R 21 is at each occurrence independently of each other selected from the group consisting of: hydrogen, deuterium, OPh, SPh, CF 3 , CN, F, Si(C 1 -C 5 -alkyl) 3 , Si(Ph) 3 ,

C 1 -C 5 -alkyl, wherein optionally one or more hydrogen atoms are independently of each other substituted by deuterium, CN, CF 3 , or F,

C 1 -C 5 -alkoxy, wherein optionally one or more hydrogen atoms are independently of each other substituted by deuterium, CN, CF 3 , or F,

C 1 -C 5 -thioalkoxy, wherein optionally one or more hydrogen atoms are independently of each other substituted by deuterium, CN, CF 3 , or F,

C 2 -C 5 -alkenyl, wherein optionally one or more hydrogen atoms are independently of each other substituted by deuterium, CN, CF 3 , or F,

C 2 -C 5 -alkynyl, wherein optionally one or more hydrogen atoms are independently of each other substituted by deuterium, CN, CF 3 , or F,

C 6 -C 18 -aryl, which is optionally substituted with one or more C 1 -C 5 -alkyl substituents,

C 3 -C 17 -heteroaryl, which is optionally substituted with one or more C 1 -C 5 -alkyl substituents,

N(C 6 -C 18 -aryl) 2 ,

N(C 3 -C 17 -heteroaryl) 2 , and

N(C 3 -C 17 -heteroaryl)(C 6 -C 18 -aryl);

R 22 and R 23 are at each occurrence independently of each other selected from the group consisting of: hydrogen, deuterium, N(R 24 ) 2 , OR 24 , Si(R 24 ) 3 , B(OR 24 ) 2 , OSO 2 R 24 , CF 3 , CN, F, Br, I,

C 1 -C 40 -alkyl, which is optionally substituted with one or more substituents R 24 and wherein one or more non-adjacent CH 2 -groups are optionally substituted by R 24 C═CR 24 , CE Ge(R 24 ) 2 , Si(R 24 ) 2 , Sn(R 24 ) 2 , C═O, C═S, C═Se, C═NR 24 , P(═O)(R 24 ), SO, SO 2 , NR 24 , O, S, or CONR 24 ,

C 1 -C 40 -alkoxy, which is optionally substituted with one or more substituents R 24 and wherein one or more non-adjacent CH 2 -groups are optionally substituted by R 24 C═CR 24 , C≡C, Si(R 24 ) 2 , Ge(R 24 ) 2 , Sn(R 24 ) 2 , C═O, C═S, C═Se, C═NR 24 , P(═O)(R 24 ), SO, SO 2 , NR 24 , O, S, or CONR 24 ,

C 1 -C 40 -thioalkoxy, which is optionally substituted with one or more substituents R 24 and wherein one or more non-adjacent CH 2 -groups are optionally substituted by R 24 C═CR 24 , C≡C, Si(R 24 ) 2 , Ge(R 24 ) 2 , Sn(R 24 ) 2 , C═O, C═S, C═Se, C═NR 24 , P(═O)(R 24 ), SO, SO 2 , NR 24 , O, S, or CONR 24 ,

C 2 -C 40 -alkenyl, which is optionally substituted with one or more substituents R 24 and wherein one or more non-adjacent CH 2 -groups are optionally substituted by R 24 C═CR 24 , C≡C, Si(R 24 ) 2 , Ge(R 24 ) 2 , Sn(R 24 ) 2 , C═O, C═S, C═Se, C═NR 24 , P(═O)(R 24 ), SO, SO 2 , NR 24 , O, S, or CONR 24 ,

C 2 -C 40 -alkynyl, which is optionally substituted with one or more substituents R 24 and wherein one or more non-adjacent CH 2 -groups are optionally substituted by R 24 C═CR 24 , C≡C, Si(R 24 ) 2 , Ge(R 24 ) 2 , Sn(R 24 ) 2 , C═O, C═S, C═Se, C═NR 24 , P(═O)(R 24 ), SO, SO 2 , NR 24 , O, S, or CONR 24 ,

C 6 -C 60 -aryl, which is optionally substituted with one or more substituents R 24 , and

C 3 —O 57 -heteroaryl, which is optionally substituted with one or more substituents R 24 ;

R 24 is at each occurrence independently of each other selected from the group consisting of: hydrogen, deuterium, OPh, SPh, CF 3 , CN, F, Si(C 1 -C 5 -alkyl) 3 , Si(Ph) 3 ,

C 1 -C 5 -alkyl, wherein optionally one or more hydrogen atoms are independently of each other substituted by deuterium, CN, CF 3 , or F,

C 1 -C 5 -alkoxy, wherein optionally one or more hydrogen atoms are independently of each other substituted by deuterium, CN, CF 3 , or F,

C 1 -C 5 -thioalkoxy, wherein optionally one or more hydrogen atoms are independently of each other substituted by deuterium, CN, CF 3 , or F,

C 2 -C 5 -alkenyl, wherein optionally one or more hydrogen atoms are independently of each other substituted by deuterium, CN, CF 3 , or F,

C 2 -C 5 -alkynyl, wherein optionally one or more hydrogen atoms are independently of each other substituted by deuterium, CN, CF 3 , or F,

C 6 -C 18 -aryl, which is optionally substituted with one or more C 1 -C 5 -alkyl substituents,

C 3 -C 17 -heteroaryl, which is optionally substituted with one or more C 1 -C 5 -alkyl substituents,

N(C 6 -C 18 -aryl) 2 ,

N(C 3 -C 17 -heteroaryl) 2 , and

N(C 3 -C 17 -heteroaryl)(C 6 -C 18 -aryl);

R A is selected from the group consisting of: hydrogen,

C 3 -C 15 -heteroaryl, wherein optionally one or more hydrogen atoms are independently of each other substituted by deuterium, halogen, C 1 -C 5 -alkyl, CN, CF 3 , SiMe 3 , SiPh 3 (Ph=phenyl), C 3 -C 15 -heteroaryl, and

C 6 -C 18 -aryl, in which optionally one or more hydrogen atoms are independently from each other substituted by C 1 -C 5 -alkyl, CN, CF 3 , and Ph, and

C 6 -C 13 -aryl, wherein optionally one or more hydrogen atoms are independently of each other substituted by a substituent independently of each other selected from the group consisting of: C 1 -C 5 -alkyl, CN, CF 3 , and

Ph, which is optionally substituted with one or more substituents independently of each other selected from the group consisting of Me, i Pr, t Bu, CN, CF 3 , and Ph,

pyridinyl, which is optionally substituted with one or more substituents independently of each other selected from the group consisting of Me, i Pr, t Bu, CN, CF 3 , and Ph,

pyrimidinyl, which is optionally substituted with one or more substituents independently of each other selected from the group consisting of Me, i Pr, t Bu, CN, CF 3 , and Ph, and

triazinyl, which is optionally substituted with one or more substituents independently of each other selected from the group consisting of Me, i Pr, t Bu, CN, CF 3 , and Ph.

24 . The organic electroluminescent device according to claim 16 , wherein R A is C 3 -C 15 -heteroaryl,

wherein, optionally, one or more hydrogen atoms are independently of each other substituted by deuterium, halogen, C 1 -C 5 -alkyl, CN, CF 3 , SiMe 3 , SiPh 3 (Ph=phenyl), C 3 -C 15 -heteroaryl, and C 6 -C 18 -aryl, in which optionally one or more hydrogen atoms are independently from each other substituted by C 1 -C 5 -alkyl, CN, CF 3 , and Ph.

25 . The organic electroluminescent device according to claim 16 , comprising one or more g-host material H P which has a lowest unoccupied molecular orbital LUMO(H P ) having an energy E LUMO (H P ) according to −2.6 eV≤E LUMO (H P ).

26 . The organic electroluminescent device according to claim 16 comprising one or more g-host materials H P which comprise or consist of:

one first chemical moiety, comprising or consisting of a structure according to any of the formulas H P -I, H P -II, H P -III, H P -IV, H P -V, H P -VI, H P -VII, H P -VIII, H P -IX, and H P -X:

and

at least one second chemical moiety comprising or consisting of a structure according to any of formulas H P -XI, H P -XII, H P -XIII, H P -XIV, H P -XV, H P -XVI, H P -XVII, H P -XVIII, and H P -XIX:

wherein each of the at least one second chemical moieties which is present in the p-host material H P is linked to the first chemical moiety via a single bond which is represented in the formulas above by a dashed line;

wherein

Z 1 is at each occurrence independently of each other selected from the group consisting of a direct bond, C(R II ) 2 , C═C(R II ) 2 , C═O, C═NR II , NR II , O, Si(R II ) 2 , S, S(O), and S(O) 2 ;

R I is at each occurrence independently of each other a binding site of a single bond linking the first chemical moiety to a second chemical moiety or is selected from the group consisting of: hydrogen, deuterium, Me, i Pr, tBu, wherein at least one R I is a binding site of a single bond linking the first chemical moiety to a second chemical moiety, and

Ph, which is optionally substituted with one or more substituents independently of each other selected from the group consisting of: Me, i Pr, t Bu, and Ph; and

R II is at each occurrence independently of each other selected from the group consisting of: hydrogen, deuterium, Me, i Pr, t Bu, and

Ph, which is optionally substituted with one or more substituents independently of each other selected from the group consisting of: Me, i Pr, t Bu, and Ph;

wherein two or more adjacent substituents may optionally form an aromatic or heteroaromatic ring system with 3-18 carbon atoms.

27 . The organic electroluminescent device according to claim 16 , wherein said organic electroluminescent device is a device selected from the group consisting of an organic light emitting diode, a light emitting electrochemical cell, and a light-emitting transistor.

28 . The organic electroluminescent device according to claim 16 , wherein the at least one light-emitting layer B comprises:

(i) 10-89.9% by weight of one or more p-host compound H P ;

(ii) 0-79.9% by weight of one or more n-host compound H N ;

(iii) 10-50% by weight of one or more TADF material E B ;

(iv) 0.1-10% by weight of one or more small FWHM emitter S B ; and

(v) 0-72% by weight of one or more solvents.

29 . The organic electroluminescent device according to claim 16 , wherein the at least one light-emitting layer B comprises:

(i) 22-87.5% by weight of one or more p-host compound H P ;

(ii) 0-65.5% by weight of one or more n-host compound H N ;

(iii) 12-40% by weight of one or more TADF material E B ;

(iv) 0.5-5% by weight of one or more small FWHM emitter S B ; and

(v) 0-65.5% by weight of one or more solvents.

30 . A method for generating green light at a wavelength of from 500 nm to 560 nm, comprising the steps of:

(i) providing an organic electroluminescent device according to claim 16 ; and

(ii) applying an electrical current to said organic electroluminescent device.

31 . The organic electroluminescent device according to claim 24 , wherein the binding site of R A according to formula S B -III-3a is one of the C 3 -C 15 -carbon atoms of the C 3 -C 15 -heteroaryl.