Organic light emitting device and materials for use in same

1. An organic light emitting device comprising an anode, a cathode and an emissive layer, wherein the emissive layer is located between the anode and the cathode, and the emissive layer comprises a host material and a phosphorescent emitter material, wherein:

the host material has the chemical structure represented by formula (3):

wherein A 1 is selected from the group consisting of a substituted or unsubstituted pyridine ring, pyrimidine ring, and triazine ring;

A 2 represents a substituted or unsubstituted aromatic hydrocarbon group having 6 to 30 ring-forming carbon atoms or a substituted or unsubstituted nitrogen-containing heterocyclic group having 1 to 30 ring-forming carbon atoms;

X 1 and X 2 are bonding groups, X 1 and X 2 respectively independently representing a single bond and a substituted or unsubstituted aromatic hydrocarbon group having 6 to 30 ring-forming carbon atoms;

Y 1 to Y 4 independently represent;

a hydrogen atom;

a fluorine atom;

a cyano group;

a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms;

a substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms;

a substituted or unsubstituted haloalkyl group having 1 to 20 carbon atoms;

a substituted or unsubstituted haloalkoxy group having 1 to 20 carbon atoms;

a substituted or unsubstituted alkylsilyl group having 1 to 10 carbon atoms;

a substituted or unsubstituted arylsilyl group having 6 to 30 carbon atoms;

a substituted or unsubstituted aromatic hydrocarbon group having 6 to 30 ring-forming carbon atoms;

a substituted or unsubstituted condensed aromatic hydrocarbon group having 6 to 30 ring-forming carbon atoms;

a substituted or unsubstituted aromatic heterocyclic group having 2 to 30 ring-forming carbon atoms; or

a substituted or unsubstituted condensed aromatic heterocyclic group having 2 to 30 ring-forming carbon atoms, adjacent ones of Y 1 to Y 4 being bondable with each other to form a ring structure, and

p and q represent integers in a range from 1 to 4 and r and s represent integers in a range from 1 to 3, Y 1 to Y 4 being the same as or different from each other when p and q represent integers in a range from 2 to 4 and r and s represent integers in a range from 2 to 3; and

the phosphorescent emitter material comprises a phosphorescent organometallic complex having a substituted chemical structure represented by one of the following partial chemical structures of the formula:

LL′L″M

wherein M is a metal that forms octahedral complexes, L, L′, L″ are equivalent or inequivalent bidentate ligands wherein each L comprises a substituted or unsubstituted phenylpyridine ligand coordinated to M through an sp 2 hybridized carbon and N; and

one of L, L′ and L″ is inequivalent to at least one of the other two,

wherein the phosphorescent emitter material comprises a phosphorescent organometallic compound having a substituted chemical structure represented by the following chemical structure:

where each R is independently selected from the group consisting of H, alkyl, alkenyl, alkynyl, alkylaryl, CN, CF 3 , C n F 2n+1 , trifluorovinyl, CO 2 R, C(O)R, NR 2 , NO 2 , OR, halo, aryl, heteroaryl, substituted aryl, substituted heteroaryl or a heterocyclic group;

Ar′, Ar″, Ar′″ and Ar″″ each independently represent a substituted or unsubstituted aryl or heteroaryl unfused substituent on the phenylpyridine ligand;

a is 0 or 1;

b is 0 or 1;

c is 0 or 1;

d is 0 or 1;

m is 1 or 2;

n is 1 or 2;

m+n is the maximum number of ligands that can be coordinated to M, and

wherein at least one of a, b, c, and d is 1 and when at least one of a and b is 1 and at least one of b and c is 1, at least one of Ar′ and Ar″ is different from at least one of Ar′″ and Ar″″.

2. The organic light emitting device of claim 1 , wherein the host material has the chemical structure represented by the formula:

3. The organic light emitting device of claim 1 , wherein the triplet energy of the host material is from about 2.0 eV to about 2.8 eV.

4. The organic light emitting device of claim 1 , wherein the phosphorescent emitter material comprises a phosphorescent organometallic complex wherein the substituted chemical structure is substituted with at least two methyl groups.

5. The organic light emitting device of claim 1 , wherein the phosphorescent emitter material comprises a metal complex, and the metal complex comprises a metal atom selected from Ir, Pt, Os, Au, Cu, Re, Ru and a ligand.

6. The organic light emitting device of claim 5 , wherein the metal complex has an ortho-metal bond.

7. The organic light emitting device of claim 6 , wherein the metal atom is Ir.

8. The organic light emitting device of claim 1 , wherein the phosphorescent emitter material comprises a phosphorescent organometallic complex having a substituted chemical structure represented by the following partial chemical structure:

9. An organic light emitting device comprising an anode, a cathode and an emissive layer, wherein the emissive layer is located between the anode and the cathode, and the emissive layer comprises a host material and a phosphorescent emitter material, wherein:

the host material has the chemical structure represented by formula (3):

wherein A 1 is selected from the group consisting of a substituted or unsubstituted pyridine ring, pyrimidine ring, and triazine ring;

A 2 represents a substituted or unsubstituted aromatic hydrocarbon group having 6 to 30 ring-forming carbon atoms or a substituted or unsubstituted nitrogen-containing heterocyclic group having 1 to 30 ring-forming carbon atoms;

X 1 and X 2 are bonding groups, X 1 and X 2 respectively independently representing a single bond and a substituted or unsubstituted aromatic hydrocarbon group forming carbon atoms;

Y 1 to Y 4 independently represent, a hydrogen atom, a fluorine atom, a cyano group, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms, a substituted or unsubstituted haloalkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted haloalkoxy group having 1 to 20 carbon atoms, a substituted or unsubstituted alkylsilyl group having 1 to 10 carbon atoms, a substituted or unsubstituted arylsilyl group having 6 to 30 carbon atoms, a substituted or unsubstituted aromatic hydrocarbon group having 6 to 30 ring-forming carbon atoms, a substituted or unsubstituted condensed aromatic hydrocarbon group having 6 to 30 ring-forming carbon atoms, a substituted or unsubstituted aromatic heterocyclic group having 2 to 30 ring-forming carbon atoms; or a substituted or unsubstituted condensed aromatic heterocyclic group having 2 to 30 ring-forming carbon atoms, adjacent ones of Y 1 to Y 4 being bondable with each other to form a ring structure, and

p and q represent integers in a range from 1 to 4 and r and s represent integers in a range from 1 to 3, Y 1 to Y 4 being the same as or different from each other when p and q represents integers in a range from 2 to 4 and r and s represent integers in a range from 2 to 3; and

the phosphorescent emitter material comprises a phosphorescent organometallic complex having a substituted chemical structure represented by one of the following partial chemical structures of the formula:

LL′L″M

wherein M is a metal that forms octahedral complexes;

L, L′, L″ are equivalent or inequivalent bidentate ligands wherein each L comprises a substituted or unsubstituted phenylpyridine ligand coordinated to M through an sp 2 hybridized carbon and N; and

one of L, L′ and L″ is inequivalent to at least one of the other two;

wherein the host material comprises an unsubstituted aromatic hydrocarbon compound having the chemical structure represented by the formula:

and wherein the phosphorescent emitter material comprises a phosphorescent organometallic compound having a substituted chemical structure represented by the following chemical structure:

where each R is independently selected from the group consisting of H, alkyl, alkenyl, alkynyl, alkylaryl, CN, CF 3 , C n F 2n+1 , trifluorovinyl, CO 2 R, C(O)R, NR 2 , NO 2 , OR, halo, aryl, heteroaryl, substituted aryl, substituted heteroaryl or a heterocyclic group;

Ar′, Ar″, Ar′″ and Ar″″ each independently represent a substituted or unsubstituted aryl or heteroaryl unfused substituent on the phenylpyridine ligand;

a is 0 or 1;

b is 0 or 1;

c is 0 or 1;

d is 0 or 1;

m is 1 or 2;

n is 1 or 2;

m+n is the maximum number of ligands that can be coordinated to M, and

wherein at least one of a, b, c, and d is 1 and when at least one of a and b is 1 and at least one of b and c is 1, at least one of Ar′ and Ar″ is different from at least one of Ar′″ and Ar″″.

10. The organic light emitting device of claim 9 , wherein at least one of the phosphorescent materials contained in the light emitting layer has a maximum value of 500 nm or more and 720 nm or less in a light emitting wavelength.