Classifications

• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
  • C08G83/00—Macromolecular compounds not provided for in groups C08G2/00 - C08G81/00
  • C08G83/002—Dendritic macromolecules
  • C08G83/003—Dendrimers
• • H—ELECTRICITY
  • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
  • H10K—ORGANIC ELECTRIC SOLID-STATE DEVICES
  • H10K85/00—Organic materials used in the body or electrodes of devices covered by this subclass
  • H10K85/30—Coordination compounds
  • H10K85/321—Metal complexes comprising a group IIIA element, e.g. Tris (8-hydroxyquinoline) gallium [Gaq3]
  • H10K85/322—Metal complexes comprising a group IIIA element, e.g. Tris (8-hydroxyquinoline) gallium [Gaq3] comprising boron
• • H—ELECTRICITY
  • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
  • H10K—ORGANIC ELECTRIC SOLID-STATE DEVICES
  • H10K85/00—Organic materials used in the body or electrodes of devices covered by this subclass
  • H10K85/30—Coordination compounds
  • H10K85/381—Metal complexes comprising a group IIB metal element, e.g. comprising cadmium, mercury or zinc
• • H—ELECTRICITY
  • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
  • H10K—ORGANIC ELECTRIC SOLID-STATE DEVICES
  • H10K85/00—Organic materials used in the body or electrodes of devices covered by this subclass
  • H10K85/60—Organic compounds having low molecular weight
  • H10K85/615—Polycyclic condensed aromatic hydrocarbons, e.g. anthracene
• • H—ELECTRICITY
  • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
  • H10K—ORGANIC ELECTRIC SOLID-STATE DEVICES
  • H10K85/00—Organic materials used in the body or electrodes of devices covered by this subclass
  • H10K85/60—Organic compounds having low molecular weight
  • H10K85/615—Polycyclic condensed aromatic hydrocarbons, e.g. anthracene
  • H10K85/626—Polycyclic condensed aromatic hydrocarbons, e.g. anthracene containing more than one polycyclic condensed aromatic rings, e.g. bis-anthracene
• • H—ELECTRICITY
  • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
  • H10K—ORGANIC ELECTRIC SOLID-STATE DEVICES
  • H10K85/00—Organic materials used in the body or electrodes of devices covered by this subclass
  • H10K85/60—Organic compounds having low molecular weight
  • H10K85/649—Aromatic compounds comprising a hetero atom
  • H10K85/655—Aromatic compounds comprising a hetero atom comprising only sulfur as heteroatom
• • H—ELECTRICITY
  • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
  • H10K—ORGANIC ELECTRIC SOLID-STATE DEVICES
  • H10K85/00—Organic materials used in the body or electrodes of devices covered by this subclass
  • H10K85/60—Organic compounds having low molecular weight
  • H10K85/658—Organoboranes
• • H—ELECTRICITY
  • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
  • H10K—ORGANIC ELECTRIC SOLID-STATE DEVICES
  • H10K85/00—Organic materials used in the body or electrodes of devices covered by this subclass
  • H10K85/791—Starburst compounds
• • H—ELECTRICITY
  • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
  • H10K—ORGANIC ELECTRIC SOLID-STATE DEVICES
  • H10K2102/00—Constructional details relating to the organic devices covered by this subclass
  • H10K2102/10—Transparent electrodes, e.g. using graphene
  • H10K2102/101—Transparent electrodes, e.g. using graphene comprising transparent conductive oxides [TCO]
  • H10K2102/103—Transparent electrodes, e.g. using graphene comprising transparent conductive oxides [TCO] comprising indium oxides, e.g. ITO
• • H—ELECTRICITY
  • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
  • H10K—ORGANIC ELECTRIC SOLID-STATE DEVICES
  • H10K50/00—Organic light-emitting devices
  • H10K50/10—OLEDs or polymer light-emitting diodes [PLED]
  • H10K50/11—OLEDs or polymer light-emitting diodes [PLED] characterised by the electroluminescent [EL] layers
• • H—ELECTRICITY
  • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
  • H10K—ORGANIC ELECTRIC SOLID-STATE DEVICES
  • H10K85/00—Organic materials used in the body or electrodes of devices covered by this subclass
  • H10K85/10—Organic polymers or oligomers
  • H10K85/111—Organic polymers or oligomers comprising aromatic, heteroaromatic, or aryl chains, e.g. polyaniline, polyphenylene or polyphenylene vinylene
  • H10K85/113—Heteroaromatic compounds comprising sulfur or selene, e.g. polythiophene
  • H10K85/1135—Polyethylene dioxythiophene [PEDOT]; Derivatives thereof
• • H—ELECTRICITY
  • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
  • H10K—ORGANIC ELECTRIC SOLID-STATE DEVICES
  • H10K85/00—Organic materials used in the body or electrodes of devices covered by this subclass
  • H10K85/10—Organic polymers or oligomers
  • H10K85/141—Organic polymers or oligomers comprising aliphatic or olefinic chains, e.g. poly N-vinylcarbazol, PVC or PTFE
  • H10K85/146—Organic polymers or oligomers comprising aliphatic or olefinic chains, e.g. poly N-vinylcarbazol, PVC or PTFE poly N-vinylcarbazol; Derivatives thereof
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
  • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
  • Y02E10/00—Energy generation through renewable energy sources
  • Y02E10/50—Photovoltaic [PV] energy
  • Y02E10/549—Organic PV cells
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
  • Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
  • Y02P70/00—Climate change mitigation technologies in the production process for final industrial or consumer products
  • Y02P70/50—Manufacturing or production processes characterised by the final manufactured product
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
  • Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10S428/00—Stock material or miscellaneous articles
  • Y10S428/917—Electroluminescent

Definitions

• This invention relates to dendrimers and light emitting devices containing them.
• Light-emitting materials fall into three classes, namely molecular, polymeric, and dendritic.
• Dendritic materials have several advantages over molecular and polymeric materials including: a) the electronic properties can be changed without altering the processing properties; b) a greater variety of chromophores can be used as the dendritic architecture can stop ⁇ - ⁇ stacking of the chromophores; c) the efficiency of light-emitting diodes can be controlled by the dendrimer generation i.e. the number of sets of branching points within a dendron; and d) the dendrimer architecture makes the formation of blends with other dendrimers, polymers and molecular materials simple.
• Dendrimers consist of dendrons or dendritic structures terminating in surface groups and a core (see Figure 1).
• Dendrons also known as dendrites have at least one, and preferably more than one, branching point.
• the branching points are atoms or groups to which at least two branches or linkers are attached. The nature of the branching points and the links between the branching points can be varied.
• a branching group is generally connected to the next branching group optionally via one or more linking groups (eg aryl - aryl' - aryl) where aryl is a branching group and aryl' a linking group. There are at least three attachments in total to a branching group, but only two are necessary to a linker group.
• the dendrimer types that are likely to have the greatest promise are those that contain mostly conjugated dendrons. These include those described in WO99/21935.
• aryl-vinyl-aryl dendrons may not be optimal for electroluminescent devices.
• the vinyl groups have been implicated as degradation sites.
• the vinyl groups in aryl-vinyl-aryl dendrons may be potential degradation sites. It may therefore be desirable to avoid vinyl groups.
• the control of colour and charge transport in dendrimers is governed by the interactions between dendrimers and is changed by altering the shape and generation of the dendrimer. Aryl-aryl'-aryl dendrons will be a different shape to aryl-vinyl-aryl dendrons.
• a light emitting device i.e. visible light
• the dendritic structures comprise branching, and optionally linking, (hetero) aryl groups wherein each aryl group is directly attached to another (hetero) aryl group.
• the dendritic structure is aryl- aryl or aryl- (aryl') a -aryl (where aryl' may be different from aryl and a is integer from 0 to 4).
• the core terminates at the single bond to the first branching group, i.e. a bond to the sp 2 hybridised ring atom of a (hetero)aryl branching group, the ring atom forming part of the dendron.
• the ring atom will be carbon.
• the present invention provides, in particular, a light-emitting device incorporating as its light emitting element a compound having the formula (I):
• Q is a proton or a surface group
• a is an integer
• DENDRITE which may be the same or different if n is greater than 1
• CORE terminating in the first single bond which is connected to an sp 2 hybridised ring atom of an (hetero)aryl group to which more than one conjugated dendritic branch is attached, said atom forming part of the DENDRITE, the CORE and/or DENDRITE being luminescent; provided that the compound is not :
• the invention provides a light emitting device incorporating as its light emitting element a compound having the formula (II):
• a is 0 or an integer which equals the number of bonding atoms of the distal end groups of DENDRITE which are not attached to a branch point.
• the parameter a increases with increasing generation. For example, in a DENDRITE which consists of two distal phenyl rings, a is 10. In a higher generation, where the DENDRITE consists of 4 distal phenyl rings, a is 20. In a preferred embodiment at least one bonding atom on each distal group is attached to a Q which is not a proton.
• conjugated dendrons indicate that they are made up of alternating double and single bonds, apart from the surface groups.
• this does not mean that the ⁇ system is fully delocalised.
• the delocalisation of the ⁇ system is dependent on the regiochemistry of the attachments.
• the dendrimers contain at least one aryl-aryl or, more generally, aryl- (aryr) a -aryl group, wherein aryl includes heteroaryl and aryl' is the same as or different from aryl and a is an integer from 0 to 4. It is to be understood that references to aryl (and aryl') include heteroaryl and fused aromatic ring systems.
• the structure is not phenyl-phenyl ' ' .
• the structure of the dendron contains x phenyl-other ⁇ tryV, ⁇ phenyl-phenyl- phenyl / or phenyl-
• one dendron can contain more than one type of link between the branch points or different branch points.
• a single dendron may contain a mixture of phenyl-phenyl branches and, say, phenyl-pyridyl branches.
• the dendrimer may have more than one luminescent moiety and the energy resulting from electrical or optical excitation may be transferred to one of them for light emission.
• the dendrimer incorporates at least two inherently at-least-partly-conjugated luminescent moieties which moieties may or may not be conjugated with each other, wherein the dendron includes at least one of the said luminescent moieties.
• the luminescent moiety or moieties further from the core of the dendrimer have a larger HOMO-LUMO energy gap than the luminescent moiety or moieties closer to or partly or wholly within the core of the dendrimer.
• the HOMO-LUMO energy gap is substantially the same although the surface groups may change the HOMO-LUMO energy gap of the chromophores at the surface of the dendrimer.
• the surface group makes the chromophore at the distal end of the dendrite of lower HOMO-LUMO energy compared to that of the next one in.
• the relative HOMO-LUMO energy gaps of the moieties can be measured by methods known per se using a UN- visible spectrophotometer.
• the graduation of HOMO-LUMO energy gap being lower in those luminescent moieties which are closer to the core may be generally beneficial in encouraging inwards charge transfer and increased light-emitting activity within the dendrimer molecules.
• One of the luminescent moieties may be, or (partly or wholly) within, the core itself, which will thus preferably have a smaller inherent HOMO-LUMO energy gap than the other luminescent moiety or moieties in the dendron,
• the dendrons themselves may each contain more than one luminescent moiety, in which case those further from the core will again preferably have larger inherent HOMO- LUMO energy gap than those closer to the core.
• the core itself need not be luminescent, although luminescent cores are generally preferred.
• Suitable surface groups for the dendrimers include branched and unbranched alkyl, especially t-butyl, branched and unbranched alkoxy, such as 2-ethylhexyloxy or n-butyloxy, hydroxy, alkylsilane, carboxy, carbalkoxy, and vinyl.
• a more comprehensive list include a further-reactable alkene, (meth)acrylate, sulphur- containing, or silicon-containing group; sulphonyl group; polyether group; C t to C ⁇ 5 alkyl (preferably t-butyl) group; amine group; mono-, di- or tri-Ci to C 15 alkyl amine group; -COOR group wherein R is hydrogen or Cj to C 15 alkyl; -OR group wherein R is hydrogen, aryl, or to C 15 alkyl or alkenyl; -O 2 SR group wherein R is C, to C 15 alkyl or alkenyl; -SR group wherein R is aryl, or to C 15 alkyl or alkenyl; -SiR 3 group wherein the R groups are the same or different and are hydrogen, C, to C I5 alkyl or alkenyl, or -SR' group (R' is aryl or to C 15 alkyl or alkenyl),
• the dendrimer is solution-processable i.e. the surface groups are such that the dendrimer can be dissolved in a solvent.
• the surface group is such that, on processing, the dendrimer can be photopatterned.
• a cross-linkable group is present which can be cross-linked upon irradiation or by chemical reaction.
• the surface group comprises a protecting group which can be removed to leave a group which can be cross-linked.
• the surface groups are selected so the dendrimers are soluble in solvents suitable for solution processing.
• the aryl (and aryl') groups within the dendrons can be typically benzene, napthalene, anthracene, fluorene, pyridine, oxadiazole, triazole, triazine, thiophene and where appropriate substituted variations. These groups may optionally be substituted, typically by C t to C 15 alkyl or alkoxy groups.
• the aryl groups at the branching points are preferably benzene rings, preferably coupled at ring positions 1, 3 and 5, pyridyl or triazinyl rings.
• the dendrons themselves can contain a, or the, fluorescent chromophore.
• the cores can be comprised of luminescent or non-luminescent moieties.
• the dendrons must contain fluorescent groups.
• the cores being luminescent they can be comprised of either organic and/or organometallic fluorophores and/or phosphors.
• Typical cores include one or more moieties of benzene, pyridine, pyrimidine, triazine, thiophene, fluorene, typically 9,9-dialkyl substituted fluorene eg.
• 9,9-dihexylfluorene divinylbenzene, distyrylethylene, divinylpyridine, pyrimidine, triazine, divinylthiophene, oxadiazole, coronene, or a fluorescent dye or marker compound or a metallic chromophore such as a lanthanide, or iridium complex, or a metalloporphyrin.
• These various rings may be substituted, for example by Cj to C 15 alkyl or alkoxy groups.
• the dendrimers for the present invention can be prepared in a similar manner to those described in O99/21935.
• the dendrons are first prepared.
• the dendrons are then reacted with a functionality to form the core.
• a dendron is prepared with an aldehyde at the foci which can then be condensed with pyrrole to form a porphyrin cored dendrimer.
• the dendrimer can be incorporated into a light emitting diode (LED), also known as an electroluminescent (EL) device, in a conventional manner.
• the dendrimer acts as the light emitting element.
• the dendrimers can be made soluble in conventional solvents such as toluene, THF, water and alcoholic solvents such as methanol.
• an organic light emitting or electroluminescent device can be formed from a light emitting layer sandwiched between two electrodes, at least one of which must be transparent to the emitted light.
• Such a device can have a conventional arrangement comprising a transparent substrate layer, a transparent electrode layer, a light emitting layer and a back electrode.
• the standard materials can be used.
• the transparent substrate layer is typically made of glass although other transparent materials such as PET can also be used.
• the anode which is generally transparent is preferably made from indium tin oxide (ITO) although other similar materials including indium oxide/tin oxide, tin oxide/antimony, zinc oxide/aluminum, gold and platinum can also be used.
• ITO indium tin oxide
• Conducting polymers such as PANI (polyaniline) or PEDOT can also be used.
• the cathode is normally made of a low work function metal or alloy such as Al, Ca, Mg, Li, or MgAl or optionally with an additional layer of LiF.
• a low work function metal or alloy such as Al, Ca, Mg, Li, or MgAl or optionally with an additional layer of LiF.
• other layers may also be present, including a hole transporting material and/or an electron transporting material.
• the substrate may be an opaque material such as silicon and the light is emitted through the opposing electrode.
• the dendrimers of the present invention can be deposited by known solution processing methods, such as spin-coating, printing, dip-coating.
• the dendrimer can be deposited as a neat film or as a blend with other organic materials (dendrimers, polymers and/or molecular compounds).
• Other organic layers for example charge transporting materials, can be deposited on top of the dendrimer film by evaporation, or by solution processing from a solvent in which the first layer is not soluble.
• the film thickness is typically 10 nm to 1000 nm, preferably less than 200 nm, more preferably less than 120 nm.
• the dendrimers can also be used in other semiconducting devices which including photodiodes, solar cells, FET or a solid state triode.
• Figure 1 shows a schematic diagram of a dendrimer
• Figure 2 shows the reaction scheme for the preparation of higher generation dendritic intermediates
• Figure 3 shows two first generation dendrimers
• Figure 4 shows a second generation Zn-porphyrin cored dendrimer
• Figures 5 - 8 show different fluorene-based core dendrimers and the preparation steps.
• Eert-butyl lithium (1.7 M, 66.0 cm 3 , 112 mmol) was added carefully to a cold (dry- ice/acetone bath) solution of GO-Br 1 (20.0 g, 70.1 mmol) in 300 cm 3 of anhydrous THF under an argon atmosphere. The mixture was stirred at -78 °C for 1 h and then tri-methyl borate (57.2 cm 3 , 421 mmol) was added slowly to the cold mixture. The reaction was stirred at -78 ° C for 2 h before being removed from the dry-ice/acetone bath. The mixture was then stirred at room temperature for further 2.5 h before being quenched with 3 M HCl (aq) (30 cm 3 ). The two layers were separated.
• either compound 4A or 4B can be used in the reaction to form the next generation dendrons.
• 4A or 4B being a dimer the number of protons in the 'HNMR should be considered as a ratio.
• Eert-butyl lithium (1.7 M, 3.0 cm 3 , 5.15 mmol) was added to a cold (dry-ice/acetone bath) solution of aryl bromide 5 (1.82 g, 3.22 mmol) in 18 cm 3 of anhydrous THF under argon atmosphere.
• the reaction mixture changing to a deep reddish brown was stirred at -78 ° C for 1 h.
• Tri-rc-butyl borate (5.2 cm 3 , 19.3 mmol) was added slowly to the mixture and the reaction was stirred at -78 °C for 1 h before being removed from the dry-ice/acetone bath.
• Isomerisation was carried out by heating the mixture of the Gl-DSB, catalytic amount of I 2 and toluene (3 cm 3 ) at reflux for 4 h. The mixture was allowed to cool, washed with aqueous sodium metabisulfite solution (10%, 1 x 5 cm 3 ), dried (MgSO 4 ) and filtered and the solvent was completely removed.
• 9-Propylfluorene (2) 9,9-Dipropylfluorene (3) and 2,7-Dibromo-9,9- dipropylfluorene (4) can be obtained following Kelley et al, J. Chem. Research (M) 1997, 2701, Compound (5) tert-Butyllithium (1.7 M inpentane, 8.5 cm 3 , 0.015 mol) was added dropwise to a solution of 2,7-dibromo-9,9-dipropylfluorene (4) (2.50 g, 6.00 mmol) in dry THF (100 cm 3 ) at -78 °C under argon.
• Compound (8) can be obtained according to Beaupre et al, Macromol. Rapid Commum., 2000, 21, 1013.
• Eert-butyl lithium (1.5 M, 23.4 cm 3 , 35.1 mmol) was added to a cold (dry-ice/acetone bath) solution of 32 (5.00 g, 21.9 mmol) in 90 cm 3 of anhydrous THF under an argon atmosphere. The mixture was stirred at -78 °C for 1 h and then 2-isopropoxy-4,4,5,5- tetramethyl-l,3,2-dioxaborolane (5.4 cm 3 , 26.3 mmol) was added rapidly to the cold mixture. The reaction was stirred at -78 °C for 2 h and the dry-ice/acetone bath was removed.
• the G2-BX 2 (21) was prepared as follows (see Figure 8). Eert-butyl lithium (1.7 M, 0.4 cm 3 , 0.644 mmol) was added to a cold (dry-ice/acetone bath) solution of the aryl bromide G2-Br. prepared in Example 8, (454 mg, 0.403 mmol) in 3 cm 3 of anhydrous THF under argon atmosphere. The mixture was stirred at -78 °C for 1.5 h. Tributyl borate (0.7 cm 3 , 2.59 mmol) was added to the mixture and the reaction was stirred at -78 °C for 1.5 h and then room temperature for further 3 h before being quenched with 3 M HCl (aq) (1 cm 3 ).
• the mixture was diluted with water (2 cm 3 ) and ether (3 cm 3 ). The two layers were separated. The aqueous layer was extracted with ether (3 x 4 cm 3 ). The organic layer and the ether extracts were combined, washed with brine (1 8 cm 3 ) and dried over anhydrous magnesium sulfate. The solvents were completely removed.
• the G2-Bx 2 (21) was prepared as follows (see
• NBS (0.73 g, 4.11 x 10' 3 mol, freshly recrystallised) was added slowly to a solution of 2-(7-Bromo-9,9-dihexylfluoren-2-yl)-thiophene (29) (1.85 g, 3.74 x 10" 3 mol) in chloroform (20 cm 3 ) and glacial acetic acid (20 cm 3 ) whilst heating under reflux. The solution was allowed to heat for a further 3 mins, cooled to RT and aqueous sodium metabisulphite solution (10 cm 3 ) was added.
• the dendrimer was spin-coated from chloroform whilst for 10f tetrahydrofuran was used.
• Devices made with a neat layer of dendrimer 31 are more efficient than those made with a neat layer of 28 (bifluorene core) but the color is blue-green rather than deep blue, hence it can be advantageous to blend the dendrimers, as the device using mixture of 28 and 31 has both a deep blue color and a good efficiency.
• the use of a hole-transporting layer (PNK) can improve the efficiency and lower the turn on voltage of the devices.

Landscapes

• Chemical & Material Sciences (AREA)
• Engineering & Computer Science (AREA)
• Materials Engineering (AREA)
• Physics & Mathematics (AREA)
• Spectroscopy & Molecular Physics (AREA)
• Inorganic Chemistry (AREA)
• Medicinal Chemistry (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Health & Medical Sciences (AREA)
• Polymers & Plastics (AREA)
• Organic Chemistry (AREA)
• Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
• Electroluminescent Light Sources (AREA)
• Nitrogen Condensed Heterocyclic Rings (AREA)
• Heterocyclic Compounds Containing Sulfur Atoms (AREA)
• Photovoltaic Devices (AREA)
• Led Devices (AREA)

Priority Applications (7)

Applications Claiming Priority (2)

Related Child Applications (2)

Publications (1)

Family

ID=9909141

Family Applications (1)

Country Status (7)

Cited By (109)

Families Citing this family (12)

Citations (1)

Family Cites Families (35)

• 2001
  • 2001-02-20 GB GBGB0104177.1A patent/GB0104177D0/en not_active Ceased
• 2002
  • 2002-02-20 JP JP2002566566A patent/JP4234434B2/ja not_active Expired - Fee Related
  • 2002-02-20 US US10/468,681 patent/US7632576B2/en not_active Expired - Lifetime
  • 2002-02-20 EP EP02700448A patent/EP1362382B1/en not_active Expired - Lifetime
  • 2002-02-20 DE DE60235796T patent/DE60235796D1/de not_active Expired - Lifetime
  • 2002-02-20 WO PCT/GB2002/000739 patent/WO2002067343A1/en not_active Ceased
  • 2002-02-20 AT AT02700448T patent/ATE463050T1/de not_active IP Right Cessation
• 2006
  • 2006-01-19 JP JP2006011581A patent/JP4965861B2/ja not_active Expired - Lifetime
• 2008
  • 2008-07-15 JP JP2008183805A patent/JP2009004797A/ja active Pending
• 2009
  • 2009-11-25 US US12/626,605 patent/US7960725B2/en not_active Expired - Fee Related
• 2011
  • 2011-06-13 US US13/159,336 patent/US8319213B2/en not_active Expired - Fee Related

Patent Citations (1)

Non-Patent Citations (4)

Also Published As

Similar Documents

Legal Events