Method of forming an optical device

0001The present invention relates to an organic optical device including an insoluble organic material layer and a method for producing the same.

0002Electroactive polymers are often used in many optics such as polymer light emitting diodes (PLEDs) disclosed in WO 90/13148, photovoltaic devices disclosed in WO 96/16449 and photodetectors disclosed in US5523555. ing.

0003A typical PLED comprises a substrate in which an anode, a cathode and an organic electron cold light radiation layer containing at least one polymer electron cold light radioactive material between the anode and the cathode are supported. In the operation, holes are injected into the device through the anode and electrons are injected into the device through the cathode. Holes and electrons combine in the organic electron cold radiation zone to form excitons, which emit light by radioactive decay. Other layers can also be present in the PLED. For example, poly (ethylenedioxythiophene) / polystyrene sulfanate (PEDT / PSS) is supplied between the anode and the organic electron cold radiation zone to facilitate the injection of holes from the anode into the organic electron cold radiation zone. Will be done.

0004In a typical PLED, for example, as described in WO99 / 48160, the electron-cooled photoradioactive material is supplied as a single layer containing a mixture of hole-transporting polymers, electron-transporting polymers and luminescent polymers. Alternatively, a single polymer can provide multiple functions for hole transport, electron transport and luminescence. Electrocooled light-emitting polymers or polymers are preferably soluble in common organic solvents to facilitate their lamination. One such kind of dissolved polymer is easily formed by Suzuki or Yamamoto polymerization, which has good thin film forming ability and allows high level control of the regularity of each part of the synthesized polymer. Polyfluorene.

0005However, in order to achieve maximization of, for example, electron or hole transport, emission, photoinduced charge generation and charge blocking or storage functions, a multilayer of different polymers, i.e. laminates, is molded on a single substrate surface. May be preferable. In addition, PEDOT / PSS may adversely affect the cold radiation zone. For example, the penetration of protons or sulphonic acid groups from the PSS into the electron cold radiation zone results in quenching of the luminescence. Therefore, it is preferable to supply a protective layer between the PEDT / PSS and the electron cold light radioactive layer. However, the preparation of polymer laminates is problematic due to the solubility of the deposited layers in the solvent used for the initial molding or subsequent layers.

0006The electron-cooled photoradiopolymer layer is formed by laminating soluble polymer precursors and then chemically converting them into an insoluble electron-cooled photoradioactive layer. For example, in WO94 / 03030, an insoluble electron-cooled photoradioactive poly (phenylene vinylene) is formed from a soluble precursor, and then yet another layer is laminated from the solution onto this insoluble layer. However, the chemical conversion process involves extreme process conditions and reaction by-products that can compromise the performance of the final product. Therefore, an electron-cooled photoradioactive polymer that dissolves in a general organic solvent is preferable. Examples of such materials are disclosed, for example, in Adv.Mater.2000 12 (23) 1737-1750, and are fully or at least partially such as polyfluorene, polyphenylene and poly (allylen vinylene) having soluble groups. Includes polymers with a backbone conjugated to, as well as polymers with a non-conjugated backbone, such as poly (vinylcarbazole).

0007WO98 / 05187 discloses a method of forming a multi-layer apparatus including a step of laminating a poly (vinylpyridine) layer on PEDT / PSS and a step of laminating a PPV precursor on a poly (vinylpyridine) layer. As mentioned above, this precursor requires strict process conditions to convert to semiconductor materials.

0008US6107452 discloses a method of forming a multi-layer apparatus in which an oligomer-containing fluorene containing a terminal vinyl group is laminated from a solution and crosslinked to form an insoluble polymer in which other additional layers are laminated. Similarly, Kim et al, Synthetic Metals 122 (2001), 363-368 disclose polymers containing triarylamine and ethynyl groups that are crosslinked following polymer lamination. The choice of polymer in both examples depends on the requirement that multiple vinyl or ethynyl sites be present.

0009IEEE Transactionson Electron Devices, 44 (8), 1263-1268, 1997 disclose the formation of two layers of poly (vinylcarbazole) PVK and pyridine-containing conjugate polymers. This is possible because the solvent for laminating the pyridine-containing conjugate polymer does not dissolve the underlayer of PVK.

0010J.Liu, ZFGuo and Y.Yang, J.Appl Phys.91,1595-1600,2002 are multi-layer devices by laminating and heating semiconductor polymers and then laminating other layers of the same polymer. Is disclosed to form.

0011WO99 / 48160 discloses PLEDs in which the hole transport material layer is supplied between the PEDT / PSS and the cold radioactive material layer.

<p num="0012"><patcit num="1"><text>International Publication No. 99/48 160 Pamphlet</text></patcit><patcit num="2"><text>U.S. Pat. No. 6,107,452</text></patcit></p>

<p num="0013"> Despite much effort being made to form multi-layer polymer optics, including PLEDs, we continue the process for manufacturing multi-layer polymer optics and equipment with improved performance. There is still a need to provide.</p>

<p num="0014"> In the first aspect, the present invention provides a method of forming an optical device including the following steps.</p><p num="0015"> Provided is a substrate containing a first electrode capable of injecting or obtaining a first type charge transporter. A first semiconductor material that dissolves in a solvent during lamination without a crosslinkable vinyl or ethynyl group is laminated on the first electrode to form a first layer that is at least partially insoluble in the solvent. A second semiconductor material is laminated from the solution in the solvent and contacted with the first layer to form a second layer containing the second semiconductor material. A second electrode is formed on the second layer from which a second type of charge transporter can be injected or obtained.</p><p num="0016"> Here, the first layer is at least partially insoluble by one or more of heat, vacuum and outside air drying treatment after laminating the first semiconductor material.</p><p num="0017"> Preferably, at least one of the first and second semiconductor materials is a polymer. More preferably, both the first and second semiconductor materials are polymers.</p><p num="0018"> Preferably, the method of the present invention comprises heating the first layer prior to forming the second layer. More preferably, the first layer is heated at a temperature higher than the glass transition temperature of the first semiconductor material.</p><p num="0019"> As used herein, "outside air drying treatment" means a treatment that allows the solvent to evaporate from the first layer without containing heat or vacuum. In particular, the outside air drying process allows the solvent to evaporate from the first layer in the outside air environment, selectively in the presence of an inert gas stream.</p><p num="0020"> Preferably, the method of the present invention comprises cleaning the first layer with a cleaning solvent in which the first semiconductor material is dissolved prior to forming the second layer.</p><p num="0021"> Preferably, the first layer is laminated from the solution in the solvent.</p><p num="0022"> Preferably, the solvent is an aromatic hydrocarbon, more preferably alkylatebenzene and more preferably toluene or xylene.</p><p num="0023"> Preferably, the first semiconductor material is a semiconductor material having no cross-linking groups other than vinyl or ethynyl groups.</p><p num="0024"> When one or both of the first and second semiconductor materials are polymers, the repeating units of the first and second semiconductor polymers are at least in adjacent repeating units to form a partially conjugated polymer backbone. It is preferably conjugated.</p><p num="0025"> Such polymers are preferably 9-substituted or 9,9'-disubstituted fluorene-2,7-diyl repeating units, most preferably selectively substituted units of formula (I).<chemistry num="1"><img id="000002" he="41" wi="45" file="JP5774571B2_D0001.tif" img-format="tif" img-content="drawing" /></chemistry> Here, R and R'are independently selected from hydrogen or selectively substituted alkyl, alkoxy, aryl, arylalkyl, heteroaryl and heteroarylalkyl, and at least one of R and R'is not hydrogen. .. More preferably, at least one of R and R'is selectively substituted C.₄-C₂₀Contains an alkyl group.</p><p num="0026"> In the first preferred embodiment of the apparatus made by the method of the invention, the first electrode is capable of injecting or acquiring holes and the second electrode is capable of injecting or acquiring electrons. is there. In this embodiment, the conductive organic material layer is preferably supplied between the first electrode and the first layer. The conductive organic material typically comprises a charged species, particularly a charged polymer having a charge balance doping agent. An example of a conductive polymer is a conductive form of PEDT or polyaniline with a charge-balanced polyacid. Preferably, the conductive organic material layer is PEDOT / PSS.</p><p num="0027"> In this example, the first semiconductor material preferably comprises a hole transport material, more preferably a polymer containing a triarylamine repeating unit. A particularly preferred triarylamine repeating unit is selected from the selectively substituted repeating units represented by Equation 1-6.<chemistry num="2"><img id="000003" he="118" wi="145" file="JP5774571B2_D0001.tif" img-format="tif" img-content="drawing" /></chemistry> Here, X, Y, A, B, C and D are selected independently of H or substituents. More preferably, one or more X, Y, A, B, C and D are alkyl, aryl, perfluoroalkyl, thioalkyl, cyano, alkoxy, heteroaryl, alkylaryl and arylalkyl groups.</p><p num="0028"> Also, a particularly preferred triarylamine repeating unit is the selectively substituted repeating unit of Equation 7. Here, Het is heteroaryl. Most preferably, Het is 4-pyridyl.<chemistry num="3"><img id="000004" he="22" wi="54" file="JP5774571B2_D0001.tif" img-format="tif" img-content="drawing" /></chemistry></p><p num="0029"> Preferably, the first semiconductor material comprises a 1: 1 regular alternating copolymer of fluorene repeating units and triarylamine repeating units.</p><p num="0030"> In a second preferred embodiment of the apparatus manufactured by the method of the present invention, the first electrode can inject or obtain electrons and the second electrode can inject or obtain holes. In this embodiment, the first semiconductor material preferably comprises an electron transport material, preferably a selectively substituted 9,9-dialkylfluorene-2,7-diyl homopolymer.</p><p num="0031"> Preferably, the first layer has a thickness of 20 nm or less, more preferably 10 nm or less, and most preferably in the range of 3-10 nm.</p><p num="0032"> Preferably, the second semiconductor polymer comprises a plurality of regions, including at least two regions, a hole transport region, an electron transport region and a light emitting region, and more preferably these three regions.</p><p num="0033"> In the second aspect, the present invention provides an optical device made according to the method of the present invention. Preferably, the optical device is an electron cold light radiating device, in particular a blue emitting electron cold light radiating device. A portion of the blue emitting electron cold light emitting device is downconverted by a phosphor capable of producing red light and green light by downconverting the blue light to provide the white emitting electron cold light emitting device.</p><p num="0034"> The method of the present invention allows the formation of polymer laminates where the first layer is particularly thin. Therefore, in the third aspect, the present invention provides an optical device that includes, in order, the following: substrate, A first electrode, capable of injecting or obtaining a first type of charge transporter, A first layer with a thickness of 20 nm or less, containing a solvent-insoluble first semiconductor polymer, A second layer in contact with a first layer containing a solvent-soluble second semiconductor polymer, A second electrode, which can inject or obtain a second type of charge transporter, Equipment including.</p><p num="0035"> In the fourth aspect, the present invention provides a method for forming an optical device including the following steps.</p><p num="0036"> Provided is a substrate supporting a conductive organic material capable of injecting or obtaining holes and providing protons. By laminating a semiconductor material capable of acquiring protons, a first layer is formed on the conductive organic material in contact with the semiconductor material. Here, the semiconductor polymer has solubility in the solvent at the time of lamination and The first layer is subjected to one or more treatments such as heating, vacuum or outside air drying treatment, and then A second layer is formed by contacting it on top of the first layer and laminating a second semiconductor material from a solution in a solvent. A method of forming a second electrode on which an electron can be injected or acquired on the second layer.</p><p num="0037"> Preferably, the first semiconductor polymer comprises a triarylamine repeating unit. More preferably, the triarylamine repeating unit is selected from the repeating units 1-7 described above.</p><p num="0038"> Preferably, the first semiconductor polymer is a 1: 1 regular alternating copolymer of fluorene repeating units and triarylamine repeating units.</p><p num="0039"> Preferably, an inorganic material layer capable of injecting or obtaining holes is supplied between the substrate and the conductive organic material. Most preferably, the inorganic material from which holes can be injected or obtained is indium tin oxide.</p><p num="0040"> Preferably, the conductive organic material is PEDOT / PSS.</p><p num="0041"> In a fifth aspect, the present invention provides a method of forming an optical device including the following steps.</p><p num="0042"> Provided is a substrate containing a first electrode capable of injecting or obtaining a first type charge transporter. The first layer is formed by laminating a first semiconductor polymer containing a fluorene repeating unit on the first electrode. Here, the first semiconductor polymer is a crosslinkable vinyl or ethynyl group, which is soluble in a solvent at the time of lamination. By laminating a first semiconductor material free of crosslinkable vinyl or ethynyl groups on the first electrode, a first layer that is at least partially insoluble in the solvent is formed. Heat treatment is applied to the first layer, A second layer containing the second semiconductor material is formed by contacting the first layer and laminating the second semiconductor material from the solution in the solvent, and A second electrode is formed on the second layer from which a second type of charge transporter can be injected or obtained.</p><p num="0043"> Preferably, at least one, more preferably both, of the first and second semiconductor materials of the fifth aspect of the invention is a polymer.</p><p num="0044"> The first semiconductor material of the fifth aspect may or may not be soluble in the solvent used for laminating the second semiconductor polymer.</p><p num="0045"> In the sixth aspect, the present invention provides a method of forming an optical device including the following steps.</p><p num="0046"> Provided is a substrate containing a first electrode capable of injecting or obtaining a first type charge transporter. The first layer is formed on the first electrode by laminating the first semiconductor polymer containing the fluorene repeating unit. Here, the first semiconductor polymer does not contain a crosslinkable vinyl or an ethynyl group and is soluble in a solvent at the time of lamination. Apply 1 or 2 or more of heating, vacuum or outside air drying treatment to the first layer, By laminating the second semiconductor polymer from the solution in the solvent, it contacts the first layer to form a second layer containing the second semiconductor polymer. A second electrode is formed on the second layer from which a second type of charge transporter can be injected or obtained.</p><p num="0047"> The first and second semiconductor polymers in any aspect of the invention are different. For example, the first and second polymers may differ in the molecular weight of the two polymers. Alternatively, or in addition to this, the first and second polymers may differ in the regularity of the sites of repeating units within the polymer. Most preferably, one of the first and second polymers differs in that it contains at least one type of repeating unit that is not present in the other polymer. Thus, for example, due to differences between the first and second polymers in terms of site regularity and / or chemical identity of repeating units, the first polymer may form a hole transport layer during lamination. The polymer of 2 may form an electron cold light radiation layer at the time of lamination. The second layer may consist only of the second semiconductor polymer or may be a mixture containing the second semiconductor polymer.</p><p num="0048"> "Red light" means radiation having a wavelength in the range of 600 to 750 nm, preferably 600 to 700 nm, more preferably 610 to 650 nm, and most preferably having an emission peak at about 650 to 660 nm.</p><p num="0049"> "Green light" means radiation having a wavelength in the range of 510 to 580 nm, preferably 510 to 570 nm.</p><p num="0050"> "Blue organic light" means radiation having a wavelength in the range of 400 to 500 nm, more preferably 430 to 500 nm.</p><p num="0051"> The "hole transport", "electron transport" and "emission" used herein are described, for example, in WO00 / 55927 and WO00 / 46321, which will be apparent to those of skill in the art. The present invention will be described in more detail with reference to the accompanying drawings using examples.</p><p num="0052"> Referring to FIG. 1, the photovoltaic device manufactured by the method of the present invention is made by laminating a substrate 1, an anode of indium tin oxide 2, an organic hole transport material layer 3, and a first soluble semiconductor polymer. It contains an insoluble material layer 4, a layer 5 created by laminating a second semiconductor polymer, and a cathode 6.</p><p num="0053"> Optical devices are susceptible to moisture and oxygen. Therefore, the substrate preferably has good barrier properties to prevent moisture and oxygen from entering the device. The substrate is generally glass, however, alternative substrates can also be used, especially if device flexibility is desired. For example, the substrate comprises a plastic as in US6268695 which discloses a substrate with alternating plastic and barrier layers or a thin glass and plastic laminate as disclosed in EP0949850.</p><p num="0054"> Although not essential, the presence of layer 3 of the hole injection material is desirable as it aids in the injection of holes from the anode into the semiconductor polymer layer. Examples of organic hole injection materials include PEDT / PSS disclosed in EP0901176 and EP0947123, or polyaniline disclosed in US5723873 and US5798170.</p><p num="0055"> The cathode 6 is chosen so that electrons are efficiently injected into the device and may include a single conductive material such as an aluminum layer as such. Alternatively, it may be a plurality of metals, eg, two layers of calcium and aluminum disclosed in WO98 / 10621, or a dielectric material such as, for example, a dielectric material such as lithium fluoride that facilitates electron injection as disclosed in WO00 / 48258. It is a thin film of.</p><p num="0056"> The device is preferably sealed with a sealing material (not shown) to prevent the ingress of moisture and oxygen. Suitable encapsulants are sheets of glass, thin films with suitable barrier properties such as alternating stacks of polymers and dielectrics as disclosed in WO01 / 81649, or secrets disclosed in WO01 / 19142, for example. Includes sex containers.</p><p num="0057"> In a practical device, at least one of the electrodes is translucent so that light is absorbed (in the case of a light responder) or emitted (in the case of a PLED device). When the anode is transparent, it typically contains indium tin oxide. An example of a transparent cathode is disclosed, for example, in GB2348316.</p><p num="0058"> The insoluble layer 4 preferably contains a polymer containing fluorene repeating units. When the insoluble layer is located between the anode and layer 5, as in the embodiment of FIG. 1, it is preferably a semiconductor polymer capable of transporting holes, eg, a fluorene repeating unit as disclosed in WO99 / 54385. And formed from a copolymer of triarylamine repeating units. Alternatively, the insoluble layer is laminated on the cathode. In this example, the insoluble layer is preferably formed from a semiconductor polymer capable of transporting electrons, such as a homopolymer of fluorene as disclosed in EP0842208. The insoluble layer 4 is formed following the lamination of the first semiconductor polymer. The layers may be completely insoluble or partially insoluble when laminated. If the first layer is only partially insoluble, the insoluble fractions in the layer may be increased by heating the layer during lamination. Any soluble first semiconductor polymer can be removed from the layer by rinsing in a suitable solvent to leave it in a completely insoluble layer.</p><p num="0059"> The second semiconductor polymer of the present invention used to form layer 5 can be a semiconductor material that can be dissolved in the same solvent as the first semiconductor polymer used to form insoluble layer 4. .. An example of a suitable second semiconductor polymer is Adv.Mater.2000 12 (23). Includes soluble poly (p-phenylene sulfide), polyphenylene and polyfluorene disclosed in 1737-1750 and its cited publications. A single polymer or multiple polymers can be laminated from solution to form layer 5. When multiple polymers are laminated, they preferably include at least two mixtures of hole-transporting polymers, electron-transporting polymers, and luminescent polymers, such as those disclosed in WO99 / 48160, if the device is a PLED. Alternatively, layer 5 can be formed from a single second semiconductor polymer comprising two or more of a hole transport region, an electron transport region and, for example, two or more of the light emitting regions disclosed in WO00 / 55927 and US6353083. The hole-transporting, electron-transporting and luminescent functions can be provided by the separated regions of the separated polymer or single polymer. Alternatively, more than one function can be achieved by a single region or polymer. In particular, a single polymer or region can be a region capable of both charge transport and luminescence. Each region can contain a single repeating unit, for example, the triarylamine repeating unit can be a hole transport region. Alternatively, each region can be a chain of repeating units, such as a chain of polyfluorene units, as an electron transport region. Different regions within such a polymer are supplied along the polymer backbone, such as US6353083, or as branching groups from the polymer backbone, such as WO01 / 62869. If the insoluble layer 4 has hole or electron transport properties, the polymer or polymer region having this property can be selectively excluded from the polymer containing layer 5.</p><p num="0060"> Both the first and second polymers of the present invention are semiconductors. The backbone of either polymer may or may not be conjugated at least partially. Examples of semiconductor polymers having at least a partially conjugated backbone include polyfluorene and polyphenylene as described above and polyarylenes such as poly (arylene vinylene). The present invention also includes first and second semiconductor polymers that do not have a conjugated backbone, such as poly (vinylcarbazole).</p><p num="0061"> The optical device manufactured by the method of the present invention is preferably a PLED when the first and second electrodes inject a charge transporter. In this case, layer 5 is a light emitting layer.</p><p num="0062"> The optical device is preferably a photovoltaic device or a photodetector when the first and second electrodes acquire a charge transporter. In this case, the second layer preferably contains a polymer capable of transporting holes and electrons.</p><p num="0063"> The inventor of the present invention has surprisingly found that the performance of polymer optics can be improved if manufactured by providing multiple layers of semiconductor polymer. In order to prevent substantial mixing of the first and second layers, the inventor of the present invention has surprisingly found that proper treatment of the first layer, especially heat treatment, makes the first layer insoluble. did.</p><p num="0064"> The inventor of the present invention surprisingly found that semiconductor polymers containing fluorene repeating units without cross-linking (eg, vinyl or ethynyl) sites were partially insoluble when laminated to form the insoluble layer 4. I found that it would be. The inventor of the present invention has discovered that this insoluble layer is (a) formed in an air or nitrogen-only atmosphere regardless of the use of the PEDOT / PSS layer. However, the inventor of the present invention applies heat, vacuum or outside air drying treatment to this insoluble layer in order to maximize the characteristics of the apparatus, and subsequently laminates polyfluorene, and particularly enhances the insolubility of the first layer. Found that it is necessary to minimize the mixing of the second and first layers. Without being bound by theory, the possible mechanism of reduced solubility due to the formation of the first layer is the loss of the soluble group attached to the 9-position of the fluorene repeating unit in the first semiconductor polymer, or Includes removal of the solvent from the polymer followed by adhesion to the surface on which the first semiconductor polymer is laminated.</p><p num="0065"> The inventor of the present invention has discovered that other semiconductor polymers, such as poly (vinylcarbazole) (PVK), can form insoluble layers under the conditions of the present invention.</p><p num="0066"> As outlined above, layer 4 is resistant to dissolution in the solvent used to laminate layer 5 under conditions typically employed for polymer lamination and solvent evaporation in the methods of the invention. is there. In addition, layer 4 was found to be resistant to dissolution when washed with the above solvents. Dissolution of layer 4 is possible under compulsory conditions in the solvent, but layer 4 is a plurality of layers under conditions typically employed for laminating semiconductor polymers in said solvent according to the methods of the invention. It is desirable that it is insoluble enough to allow the formation of an electroactive organic layer. The term "insoluble" should therefore be interpreted in this way.</p><p num="0067"> The described process has been found to improve the efficiency and longevity of PLEDs. Without being bound by theory, the following facts can act as increasing factors.</p><p num="0068"> When the first layer is located between the anode and the second layer, it can act as a hole transporting and electron blocking layer.</p><p num="0069"> When a PEDT / PSS layer is used, the insoluble layer can prevent protons from entering the second layer from the acidic PSS material. This is especially applicable when the polymer contains basic units such as amines of formula 1-6 or Het groups within the range of formula 7, such as pyridyl capable of obtaining protons.</p><p num="0070"> The layer thinness achieved, especially by adopting a spin-rinsing process, can allow charge blockage without causing damage to equipment properties that can be caused by thicker layers, such as high operating voltages. ..</p><p num="0071">General procedure The present invention is embodied using the polymer F8-TFB disclosed in WO99 / 54385 shown below as the first semiconductor polymer.<chemistry num="4"><img id="000005" he="41" wi="77" file="JP5774571B2_D0001.tif" img-format="tif" img-content="drawing" /></chemistry></p><p num="0072">The general process is as follows.</p><p num="0073"> 1) PEDOT / PSS, which is available from Bayer as Baytron P®, is spin-coated on an indium tin oxide supported on a glass substrate (available from Applied Films, Colorado, USA).</p><p num="0074"> 2) A layer of hole transport polymer is laminated by spin coating from a xylene solution having a concentration of 2% w / v.</p><p num="0075"> 3) The layer of hole transport material is heated in an inert (nitrogen) atmosphere.</p><p num="0076"> 4) Arbitrarily spin wash the substrate in xylene to remove residual soluble hole transport material.</p><p num="0077"> 5) Laminate the second semiconductor polymer from the xylene solution by spin coating.</p><p num="0078"> 6) Laminate the NaF / Al cathode on the second semiconductor polymer according to the process disclosed in WO 03/012891 and seal the device with an airtight metal seal available from Saes Getters SpA.</p><p num="0079"> Parameters within this general process can change. In particular, F8-TFB may be increased to a concentration of about 3% w / v, and a concentration of 0.5% w / v can be used to provide a particularly thin film. The selective heating process can be continued for a suitable length of up to about 2 hours. The selective heating step can be carried out at a suitable temperature up to about 220 ° C., but is preferably above the glass transition temperature of the laminated polymer. It is self-evident to those skilled in the art that the overheating temperature is such that the first and / or second polymers, as well as other equipment elements such as PEDOT / PSS, undergo thermal degradation if the heating temperature is excessive. It must be selected accordingly. Finally, the inventor of the present invention has discovered that the thickness of the first layer can be modified by proper selection of the molecular weight (Mw) of the first semiconductor polymer. Thus, F8-TFB with Mw of about 50,000 can be as thin as about 2 nm, and with Mw of about 250,000-300,000 it can be as thick as about 15 nm.</p>

0080<figref num="1">FIG. 1 shows a PLED or photovoltaic device made according to the method of the present invention.</figref><figref num="2">FIG. 2 shows a comparative plot of efficiency vs. bias for the first blue electron cold light emitting device and the two control devices.</figref><figref num="3">Figure 3 shows a plot of efficiency vs. bias for the red electron cold light emitter.</figref><figref num="4">FIG. 4 shows a plot of efficiency vs. bias for a blue electron cold light emitting device with or without spin cleaning.</figref><figref num="5">FIG. 5 shows a comparative plot of efficiency vs. bias for the second blue electron cold light emitting device and control device.</figref>

0081Hereinafter, aspects of the present invention will be described in detail based on examples.

<p num="0082"> As the first semiconductor polymer, F8-TFB, and as the second semiconductor polymer (F8-TFB polymer, TFB and PFB repeating units are as shown below, for example, disclosed in WO99 / 54385). , 70% 9,9-dioctylfluorene-2,7-diyl, 10% 9,9-diphenylfluorene-2,7-diyl, blue electrons containing 10% TFB repeating units and 10% PFB repeating units The above general procedure was performed using cold photoradiopolymers. The first and second semiconductor polymers were prepared by Suzuki polymerization, eg, as described in WO00 / 53858.</p><p num="0083"> The first semiconductor layer of F8-TFB was heat treated at 180 ° C. for 1 hour prior to laminating the second semiconductor polymer.<chemistry num="5"><img id="000006" he="45" wi="43" file="JP5774571B2_D0001.tif" img-format="tif" img-content="drawing" /></chemistry><chemistry num="6"><img id="000007" he="46" wi="61" file="JP5774571B2_D0001.tif" img-format="tif" img-content="drawing" /></chemistry></p><p num="0084"> FIG. 2 shows the effect of the efficiency of the heat treatment of the present invention. Compare the three devices. Equipment of Example 1 (F8-TFB first layer is heated to 180 ° C); First control device not supplied with F8-TFB first layer (ie, step 2-4 omitted); Heating step 3 A second control device with a first layer of F8-TFB that is not subjected to. As can be seen by comparing the results of the first and second control devices, the insertion of the F8-TFB layer results in an improvement in efficiency (as reported in WO99 / 48160), but the most important improvement is the book. It is obtained from the device of the invention, that is, the device in which the F8-TFB layer is heated.</p>

<p num="0085"> 3% 4,7-bis (2-thiophene-5-yl) -2,1,3-benzothiadiazole repeating unit (disclosed in WO 01/49768), 80% 9,9-dioctylfluorene-2, The red cold light emitting polymer containing 7-diyl, 30% 2,1,3-benzothiadiazole-4,7-diyl repeating unit and 17% TFB repeating unit is referred to as the second semiconductor polymer (hereinafter referred to as "red polymer"). ), The procedure of Example 1 was performed.</p><p num="0086"> Figure 3 shows the efficiency-bias curve of this device and a comparison with a control device containing a red polymer that is not supplied with the insoluble layer of F8-TFB (ie, step 2-4 omitted).</p>

<p num="0087"> Poly (9-vinylcarbazole) (PVK) (Aldrichcatalogue number 18260-5; average Mw ca 1,100,000) as the first semiconductor polymer and poly (9,9-dihexyl full), a blue luminescent polymer purchased from American Dye Source, Inc. The above general procedure was performed using olenyl-2,7-diyl) (PFO) (Cat. No. ADS130BE; mean Mw ca. 300,000).</p><p num="0088"> The PVK layer was heated at 200 ° C. for 1 hour prior to laminating the PFO layer.</p><p num="0089"> FIG. 5 shows that the efficiency is improved when the intermediate PVK layer is heat-treated or exposed to the outside air drying treatment as compared with the control device having no PVK layer.</p><p num="0090"> As can be seen from the cited figures, the inclusion of the insoluble layer of the present invention results in a substantial improvement in equipment properties. In addition, the life of the device (ie, the time it takes for the brightness of the device to drop to half its original value at a fixed current) and brightness are at least unharmed by the inclusion of the insoluble layer and are improved in some cases. ing.</p><p num="0091"> The insoluble layer is formed with or without heating the F8-TFB layer, but the thickness of the insoluble layer is thicker when the F8-TFB is heated.</p><p num="0092"> The second semiconductor polymer can be laminated without spin cleaning of the first layer. This is preferably done when the first semiconductor polymer is spin-coated from a dilute solution to form a first layer that is thin enough to turn completely insoluble, but the present invention is further described. It also includes the lamination of the second semiconductor polymer when the first layer is only partially insoluble and the soluble part is not removed. In this example, some mixing occurs in the second layer of the first and second semiconductor polymers. FIG. 4 shows efficiency-bias curves for two devices made by the method of the invention with and without spin cleaning using a blue polymer. This figure shows that the omission of spin cleaning has little effect on equipment characteristics.</p><p num="0093"> Although the above example describes the lamination of the first and second layers by spin coating, the first and second layers of the present invention are disclosed in other techniques, in particular the inkjet print disclosed in EP0880303, EP0851714. They may be laminated by techniques suitable for making full color displays such as laser transfer, flexographic printing, screen printing and doctor blade coating. If the second semiconductor material is laminated by inkjet printing, the use of spin cleaning may be advantageous over the corresponding spin coat lamination as the inkjet printing uses less solvent and semiconductor material.</p><p num="0094">Application example In order to provide a device capable of emitting white light, downconverter particles are formed on the outer surface of the substrate of the device of Example 1 (blue polymer) as described in Applied Physics Letters 80 (19), 3470-3472, 2002. It was attached.</p><p num="0095"> Although the present invention has been described by certain typical embodiments, many variations, modifications and / or features disclosed herein are provided without departing from the scope of the invention as defined by the claims. The combination turns out to be self-evident to those skilled in the art.</p>