JP2013222520A - Organic electroluminescent display device having color filter layer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a color filter substrate suitable for an image display device, specifically an organic electroluminescent display device, high in reliability and less in defects, and an organic electroluminescent display device including the color filter substrate, clear and excellent in display quality.SOLUTION: In an organic electroluminescent display device, a resin used in a coloring layer constituting a color filter layer is a polyimide resin.

Description

  The present invention relates to a display device, and more particularly to an organic electroluminescence display device having a color filter layer.

  In recent years, organic electroluminescence displays have attracted attention as one of new thin displays, and have begun to appear on the market as display displays for mobile phones and mobile devices. The liquid crystal display, the pioneer of thin displays, is non-self-luminous, whereas the organic display is a self-luminous display element. It is superior to liquid crystal displays in that it can achieve smoother video images, and is considered a promising candidate for next-generation thin displays.

  As a method for full-coloring an organic electroluminescence display, development of an RGB coating method for forming red (R), green (G), and blue (B) light emitting materials has been progressing. As the size of the film increases, there are adverse effects such as an increase in cost due to the enlargement of the film forming apparatus and a limit to high definition, and various methods are being studied. In particular, a color filter system that combines a white light-emitting organic EL element and a color filter substrate having RGB colored layers attracts attention, and various proposals have been made (for example, Patent Documents 1 to 3).

  An example of a color filter type organic electroluminescence display is shown in FIG. A TFT 2 for an organic electroluminescence driving element is formed on a glass substrate 1. A color filter layer 3 is formed on the TFT 2. The overcoat layer 4 protects the color filter layer 3. An anode layer 5 made of ITO is connected to the TFT 2, and an insulating film 6 is formed so as to cover the end of the anode layer 5. An organic electroluminescence layer 7 is formed on the anode layer 5, and a cathode layer 8 is formed on the organic electroluminescence layer 7. These are sealed with a sealant 9 and a sealing glass 10.

  The white light emitted from the organic electroluminescence layer 7 passes through the RGB pixels of the color filter layer 3 and is subjected to chromaticity conversion, thereby enabling full color display. Therefore, since only one type of organic electroluminescence layer 7 emits white light is required, the organic electroluminescence layer 7 is superior to the RGB coating method in terms of cost, production yield, and ease of enlargement.

  However, in such a color filter type organic electroluminescence display, defects (defects such as dark spots) due to impurities and moisture are likely to occur due to the principle of the organic electroluminescence element that converts electric energy into light. When a color filter substrate is used, stable production and image display are difficult, and the solution has been desired. In addition, when forming the anode layer 5 made of ITO, it is formed at a temperature of 240 ° C. or higher, and the organic electroluminescence element converts electric energy into light as described above, but it cannot be converted into light. Therefore, the conventional color filter substrate has a problem in heat resistance, and the chromaticity changes before and after the formation of the anode layer 5 or during the operation of the organic electroluminescence display. there were.

JP 2004-227853 A JP 2004-273317 A JP 2010-072106 A

  The present invention has been made in view of these problems, and an organic electroluminescence display device having few defects such as dark spots, no change in chromaticity, excellent display quality, and high display reliability. The purpose is to provide.

  The above problem can be solved by the following means. That is, an organic electroluminescence display device having at least a color filter layer, wherein the resin used in the colored layer constituting the color filter layer is a polyimide resin.

  The organic electroluminescence display device according to claim 1, further comprising a TFT for driving the organic electroluminescence display element, wherein the color filter layer is formed on the same substrate as the TFT.

  According to the present invention, it is possible to provide an organic electroluminescence display device that has few defects such as dark spots, has no change in chromaticity, has excellent display quality, and has high display reliability.

It is a schematic sectional drawing which shows an example (structure 1) of the image display apparatus in this invention. It is a schematic sectional drawing which shows an example (structure 2) of the image display apparatus in this invention. It is a schematic sectional drawing which shows an example (structure 3) of the image display apparatus in this invention.

  Embodiments of the present invention will be described below.

  The present invention is an organic electroluminescence display device having a color filter layer, wherein the resin used in the colored layer constituting the color filter layer is a polyimide resin. When the resin used for the colored layer is a polyimide resin, impurities and moisture are hardly oozed out, and defects such as dark spots are reduced. Moreover, heat resistance is high and chromaticity does not change easily.

  In order to form a color filter layer comprising a polyimide resin, at least a non-photosensitive color paste comprising a polyamic acid, a colorant, and a solvent is applied on the substrate, and then dried by air drying, heat drying, vacuum drying, etc. A non-photosensitive polyamic acid coloring film is formed, a desired pattern is formed using a positive photoresist, the photoresist is alkali peeled, and finally heated at 200 to 300 ° C. for 1 minute to 3 hours to form a colored layer Is generally cured (polyimidized).

  The non-photosensitive color paste used in the present invention is described below.

  The polyamic acid contained in the non-photosensitive color paste can be obtained by reacting tetracarboxylic dianhydride and diamine.

For the synthesis of polyamic acid, for example, an aliphatic or alicyclic one can be used as a tetracarboxylic dianhydride, and specific examples thereof include 1,2,3,4-cyclobutanetetra. Carboxylic dianhydride, 1,2,3,4-cyclopentanetetracarboxylic dianhydride, 1,2,3,5-cyclopentanetetracarboxylic dianhydride, 1,2,4,5-bicyclohexene Tetracarboxylic dianhydride, 1,2,4,5-cyclohexanetetracarboxylic dianhydride, 1,3,3a, 4,5,9b-hexahydro-5- (tetrahydro-2,5-dioxo-3- Furanyl) -naphtho [1,2-C] furan-1,3-dione. Moreover, when an aromatic material is used, a polyamic acid that can be converted into a film having good heat resistance can be obtained.

  Specific examples thereof include 3,3 ′, 4,4′-benzophenonetetracarboxylic dianhydride, pyromellitic dianhydride, 3,4,9,10-perylenetetracarboxylic dianhydride, 3, 3 ', 4,4'-diphenylsulfonetetracarboxylic dianhydride, 4,4'-oxydiphthalic anhydride, 3,3', 4,4'-biphenyltetracarboxylic dianhydride, 1,2,5 , 6-Naphthalenetetracarboxylic dianhydride, 3,3 ", 4,4" -paraterphenyltetracarboxylic dianhydride, 3,3 ", 4,4" -metaterphenyltetracarboxylic dianhydride Is mentioned. In addition, when a fluorine-based material is used, a polyamic acid that can be converted into a film having good transparency in a short wavelength region can be obtained. As a specific example, 4,4 ′-(hexafluoroisopropylidene ) Diphthalic anhydride. In addition, this invention is not limited to these, The tetracarboxylic dianhydride is used 1 type (s) or 2 or more types.

  Further, as the diamine, for example, aliphatic or alicyclic ones can be used, and specific examples thereof include 1,3-diaminocyclohexane, 1,4-diaminocyclohexane, 4,4′-diamino. -3,3'-dimethyldicyclohexylmethane, 4,4'-diamino-3,3'-dimethyldicyclohexyl and the like. Moreover, when an aromatic material is used, a polyamic acid that can be converted into a film having good heat resistance can be obtained.

  Specific examples thereof include 4,4′-diaminodiphenyl ether, 3,4′-diaminodiphenyl ether, 4,4′-diaminodiphenylmethane, 3,3′-diaminodiphenylmethane, 4,4′-diaminodiphenylsulfone, 3, 3'-diaminodiphenyl sulfone, 4,4'-diaminodiphenyl sulfide, m-phenylenediamine, p-phenylenediamine, 2,4-diaminotoluene, 2,5-diaminotoluene, 2,6-diaminotoluene, benzidine, 3 , 3'-dimethylbenzidine, 3,3'-dimethoxybenzidine, o-tolidine, 4,4 "-diaminoterphenyl, 1,5-diaminonaphthalene, 3,3'-dimethyl-4,4'-diaminodiphenylmethane, 4,4'-bis (4-aminophenoxy) biphenyl, 2,2 Bis [4- (4-aminophenoxy) phenyl] propane, bis [4- (4-aminophenoxy) phenyl] ether, bis [4- (4-aminophenoxy) phenyl] sulfone, bis [4- (3 -Aminophenoxy) phenyl] sulfone, etc. In addition, when a fluorine-based one is used, a polyamic acid that can be converted into a film having good transparency in a short wavelength region can be obtained, and a specific example thereof 2,2-bis [4- (4-aminophenoxy) phenyl] hexafluoropropane and the like.

  Moreover, when siloxane diamine is used as a part of diamine, the adhesiveness with an inorganic substrate can be made favorable. Siloxane diamine is usually used in an amount of 1 to 20 mol% in the total diamine. If the amount of siloxane diamine is too small, the effect of improving the adhesiveness is not exhibited, and if it is too large, the heat resistance is lowered. Specific examples of the siloxane diamine include bis-3- (aminopropyl) tetramethylsiloxane. The present invention is not limited to this, and one or more diamines are used. In general, the polyamic acid is synthesized by mixing and reacting a tetracarboxylic dianhydride and a diamine in a polar organic solvent. At this time, the polymerization degree of the resulting polyamic acid can be adjusted by the mixing ratio of diamine and tetracarboxylic dianhydride.

  In addition, there are various methods for obtaining polyamic acid, such as reacting tetracarboxylic acid dichloride and diamine in a polar organic solvent and then removing hydrochloric acid and the solvent to obtain polyamic acid.

  The colorant used in the non-photosensitive color paste of the present invention is not particularly limited as long as it is excellent in light resistance, heat resistance and chemical resistance. Specific examples of typical pigments are indicated by color index (CI) numbers. Examples of yellow pigments include Pigment Yellow 20, 24, 83, 86, 93, 94, 109, 110, 117, 125, 137, 138, 139, 147, 148, 153, 154, 166, 173, and the like. Examples of orange pigments include CI Pigment Orange 13, 31, 36, 38, 40, 42, 43, 51, 55, 59, 61, 64, 65, and the like. Examples of the red pigment include Pigment Red 9, 97, 122, 123, 144, 149, 166, 168, 177, 180, 192, 215, 216, 224 and the like. Examples of purple pigments include pigment violet 19, 23, 29, 32, 33, 36, 37, 38, and the like. Examples of blue pigments include Pigment Blue 15 (15: 3, 15: 4, 15: 6, etc.), 21, 22, 60, 64, and the like. Examples of green pigments include Pigment Green 7, 10, 36, 47, 58, and the like. In the present invention, various pigments can be used without being limited thereto. In addition, you may use the pigment to which surface treatments, such as a rosin process, an acidic group process, a basic process, are given as needed.

  As a solvent in the non-photosensitive color paste of the present invention, a solvent that dissolves polyamic acid is generally used. Specific examples include polar amide solvents such as N-methyl-2-pyrrolidone, N, N-dimethylacetamide, N, N-dimethylformamide, β-propiolactone, γ-butyrolactone, γ-valerolactone, Examples include lactones such as δ-valerolactone, γ-caprolactone, and ε-caprolactone. In addition to these solvents, ethylene glycol or propylene glycol derivatives such as methyl cellosolve, ethyl cellosolve, methyl carbitol, ethyl carbitol, propylene glycol monoethyl ether, propylene glycol monoethyl ether acetate, ethyl acetoacetate, methyl- Aliphatic esters such as 3-methoxypropionate and 3-methyl-3-methoxybutyl acetate can also be added as a co-solvent.

In the production of the non-photosensitive color paste of the present invention, a method in which a polyamic acid solution is mixed with a pigment dispersion in which a solvent and a pigment are mixed and dispersed in advance, or a polyamic acid, a solvent, and a pigment are mixed. A dispersion method or the like can be used. About selection of these manufacturing methods, it is preferable to select a suitable thing suitably according to the kind of pigment.
In the paste of the present invention, the method for dispersing the pigment is not particularly limited, and various methods such as a ball mill, a sand grinder, a three roll mill, and a high speed impact mill can be used.

  In the paste of the present invention, a surfactant may be added to the paste of the present invention for the purpose of improving the coating property, drying of the colored film, or improving the dispersibility of the pigment. The addition amount of the surfactant is usually 0.001 to 10% by weight, preferably 0.01 to 1% by weight of the pigment. If the addition amount is too small, there is no effect of improving the coating property, drying property of the colored film, or improving the dispersibility of the pigment, and if it is too much, the coating property is poor or the pigment is aggregated.

  Specific examples of the surfactant include anionic surfactants such as ammonium lauryl sulfate and polyoxyethylene alkyl ether sulfate triethanolamine, cationic surfactants such as stearylamine acetate and lauryltrimethylammonium chloride, lauryldimethylamine oxide, Examples include amphoteric surfactants such as lauryl carboxymethyl hydroxyethyl imidazolium betaine, and nonionic surfactants such as polyoxyethylene lauryl ether, polyoxyethylene stearyl ether, and sorbitan monostearate. In this invention, it is not limited to these, Surfactant can use 1 type (s) or 2 or more types. The surfactant can be added at any time during or before or after the pigment dispersion process. However, care must be taken because the dispersibility of the pigment may change depending on the point of addition.

  A dispersant can be added to the non-photosensitive color paste of the present invention for the purpose of improving the dispersibility of the pigment. As the dispersant, the above-described surfactants and other compounds, particularly compounds that are easily adsorbed on the surface of the pigment can be used. The dispersant can be added at any time during or before the pigment dispersion step.

As a method of applying the non-photosensitive color paste of the present invention on a substrate, a method of applying to a substrate by a spin coater, a bar coater, a blade coater, a roll coater, a die coater, a screen printing method, or the like, or immersing the substrate in a solution Various methods, such as a method and spraying a solution on a substrate, can be used. As the substrate, a transparent substrate such as soda glass, non-alkali glass, borosilicate glass, or quartz glass, or a semiconductor substrate such as silicon or gallium arsenide is usually used, but is not particularly limited thereto. In addition, when applying a paste on a substrate, if the substrate surface is treated with an adhesion aid such as a silane coupling agent, an aluminum chelating agent, or a titanium chelating agent, the adhesion between the colored coating and the substrate can be improved. it can.

  The configuration of the organic electroluminescence display device of the present invention may be configurations 2 and 3 as shown in FIGS. 2 and 3 in addition to the configuration 1 shown in FIG.

In FIG. 2, an organic electroluminescence driving TFT 12 is formed on a glass substrate 11. An anode layer 14 made of ITO connected to the TFT 12 is formed on the overcoat layer 13. An insulating film 15 is formed so as to cover an end portion of the anode layer 14, and an organic electroluminescence layer 16 is formed on the anode layer 14. Further, the organic EL substrate 24 is obtained by forming the cathode layer 17 on the organic electroluminescence layer 16. On the other hand, a color filter substrate 25 is formed by forming a black matrix layer 19, a color filter layer 20, an overcoat layer 21, and an inorganic barrier layer 22 on a glass substrate 18.
In the configuration 2, the organic electroluminescence substrate 24 and the color filter substrate 25 are sealed with a sealing agent 23 under vacuum.

  In FIG. 3, a light shielding layer 27, a color filter layer 28, an overcoat layer 29, and an inorganic barrier layer 30 are formed on a glass substrate 26. An anode layer 31 made of ITO is formed on the inorganic barrier layer 30, and an insulating layer 32 is formed at the end of the anode layer 31. An organic electroluminescence layer 33 is formed thereon, and a cathode layer 34 is further formed thereon. In the configuration 3, the sealing glass 35 is sealed with the sealing agent 36.

  Even in configurations 2 and 3, by using the color filter layer made of the polyimide resin of the present invention, an effect of excellent display reliability can be expressed, but in these configurations, the color filter layer comes out of the inorganic barrier layer. It is possible to reduce the penetration of moisture and organic gas into the organic electroluminescence layer. In this respect, the effect of the present invention is more effective in the configuration 1 in which it is difficult to provide the inorganic barrier layer.

  That is, it is preferable that the color filter layer is formed on the same substrate as the TFT for driving the organic electroluminescence display element and applied to the organic electroluminescence display device.

  The configuration 1 will be described below with reference to FIG.

  An example of a color filter type organic electroluminescence display is shown in FIG.

After applying the non-photosensitive color paste comprising at least a polyamic acid, a colorant, and a solvent on the substrate on which the TFT 2 is formed, it is dried by air drying, heat drying, vacuum drying, or the like to form a non-photosensitive polyamic acid colored film. Form. The thickness of the polyamic acid colored coating is usually in the range of 0.5 to 3.0 μm. In the case of heat drying, it is preferable to use an oven, a hot plate, or the like and perform the treatment at 60 to 200 ° C. for 1 to 60 minutes. Next, a positive type photoresist is applied on the polyamic acid-colored coating film thus obtained, and is heated and dried at 60 to 150 ° C. for 1 to 30 minutes using a hot plate or the like (prebaking). Next, using a photomask and a proximity exposure apparatus, an ultraviolet ray having an h-ray exposure of 20 to 300 mJ / cm ² is irradiated to print a target pattern, and then alkali development is performed to obtain a colored layer in a desired pattern at a desired position. . The photoresist is alkali peeled, and finally the colored layer is cured (polyimide) by heating at 200 to 300 ° C. for 1 minute to 3 hours.

  The present invention is characterized in that since the resin used in the colored layer forming the color filter layer is a polyimide resin, impurities and moisture are hardly oozed out and defects such as dark spots are reduced.

That is, as a suitable color filter layer used for an organic electroluminescence display, moisture, nitrogen, and monoxide generated from each RGB colored layer, unit volume (mm) ³ when heated to 300 ° C. in a helium atmosphere The total gas generation amount including carbon, carbon dioxide, organic gas, etc. is preferably 3.0 (wtppm) or less. Also, the water content is 2.0 (wtppm) or less, the total of nitrogen / carbon monoxide / carbon dioxide is 1.0 (wtppm) or less, and the organic gas is 1.0 (wtppm) or less with respect to the total gas generation amount. Is preferred.

  As a method for measuring the amount of generated gas, temperature-programmed desorption-mass spectrometry can be used. For example, a substrate on which a colored layer cut to about 10 mm × 20 mm is formed is prepared in a helium atmosphere. Under the atmosphere of helium flow of 50 ml / min, the amount of gas generated under the condition of a heating rate of 10 ° C./min from room temperature to 300 ° C. can be quantified and observed as a peak of each gas mass number.

  Next, an overcoat layer 4 for surface planarization is formed thereon. As the performance required for the overcoat layer, flatness, high transmittance, low degassing property, high heat resistance and pattern workability are required. As a material for the overcoat, any of a polyimide resin, an acrylic resin, and a siloxane resin may be used as long as the above requirements are satisfied. In the present invention, a positive photosensitive siloxane paste will be described as an example.

The positive photosensitive siloxane paste is composed of at least an alkali-soluble polysiloxane resin, a naphthoquinonediazide compound, a solvent, and a metal chelate compound.
The polysiloxane in the present invention is synthesized by hydrolysis and partial condensation of a monomer such as organosilane. A general method can be used for hydrolysis and partial condensation. For example, a solvent, water and, if necessary, a catalyst are added to the mixture, and the mixture is heated and stirred at 50 to 150 ° C., preferably 90 to 130 ° C. for about 0.5 to 100 hours. During stirring, if necessary, hydrolysis by-products (alcohols such as methanol) and condensation by-products (water) may be distilled off by distillation. There is no restriction | limiting in particular as said reaction solvent. The addition amount of the solvent is preferably 10 to 1000 parts by weight with respect to 100 parts by weight of the monomer such as organosilane. The amount of water used for the hydrolysis reaction is preferably 0.5 to 2 mol with respect to 1 mol of the hydrolyzable group.

  Although there is no restriction | limiting in particular in the catalyst added as needed, An acid catalyst and a base catalyst are used preferably. Specific examples of the acid catalyst include hydrochloric acid, nitric acid, sulfuric acid, hydrofluoric acid, phosphoric acid, acetic acid, trifluoroacetic acid, formic acid, polyvalent carboxylic acid or anhydride thereof, and ion exchange resin. Specific examples of the base catalyst include triethylamine, tripropylamine, tributylamine, tritylamine, trihexylamine, triheptylamine, trioctylamine, diethylamine, triethanolamine, diethanolamine, sodium hydroxide, potassium hydroxide, amino Examples include alkoxysilanes having groups and ion exchange resins. The addition amount of the catalyst is preferably 0.01 to 10 parts by weight with respect to 100 parts by weight of the monomer such as organosilane.

The naphthoquinone diazide compound is not particularly limited, but is preferably a compound in which naphthoquinone diazide sulfonic acid is ester-bonded to a compound having a phenolic hydroxyl group, and the ortho position and the para position of the phenolic hydroxyl group of the compound are independently hydrogenated. Or a compound which is any of hydroxyl groups.
The addition amount of the naphthoquinone diazide compound is not particularly limited, but is preferably 2 to 30 parts by weight, more preferably 3 to 15 parts by weight with respect to 100 parts by weight of the alkali-soluble resin.

  When the addition amount of the naphthoquinone diazide compound is less than 1 part by weight, the dissolution contrast between the exposed part and the unexposed part is too low, and the photosensitivity sufficient for practical use is not exhibited. Further, in order to obtain a better dissolution contrast, 5 parts by weight or more is preferable. On the other hand, when the addition amount of the naphthoquinone diazide compound is more than 30 parts by weight, the coating film may be whitened due to poor compatibility between the polysiloxane and the naphthoquinone diazide compound, or coloring due to decomposition of the quinone diazide compound that occurs during thermal curing may occur. As a result, the colorless transparency of the cured film decreases. Further, in order to obtain a highly transparent film, the amount is 20 parts by weight or less, preferably 15 parts by weight or less, more preferably 10 parts by weight or less.

  Although there is no restriction | limiting in particular in the solvent to be used, Preferably the compound which has alcoholic hydroxyl group is used. When these solvents are used, the alkali-soluble resin and the quinonediazide compound are uniformly dissolved, and high transparency can be achieved without whitening the film even when the composition is coated.

  The compound having an alcoholic hydroxyl group is not particularly limited, but is preferably a compound having a boiling point of 110 to 250 ° C. under atmospheric pressure. When the boiling point is higher than 250 ° C., the amount of residual solvent in the film increases and film shrinkage during curing increases, and good flatness cannot be obtained. On the other hand, if the boiling point is lower than 110 ° C., the coating properties deteriorate, such as drying at the time of coating is too fast and the film surface becomes rough.

  Specific examples of the compound having an alcoholic hydroxyl group include acetol, 3-hydroxy-3-methyl-2-butanone, 4-hydroxy-3-methyl-2-butanone, 5-hydroxy-2-pentanone, 4-hydroxy- 4-methyl-2-pentanone (diacetone alcohol), ethyl lactate, butyl lactate, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol mono n-propyl ether, propylene glycol mono n-butyl ether, propylene glycol mono t- Butyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, 3-methoxy-1- Pentanol, 3-methyl-3-methoxy-1-butanol. In addition, you may use the compound which has these alcoholic hydroxyl groups individually or in combination of 2 or more types.

  Although there is no restriction | limiting in particular in content of a metal chelate compound, (a) It is 0.1-5 weight part with respect to 100 weight part of alkali-soluble resin. More preferably, it is 0.3 to 4 parts by weight. By being in the above range, it is possible to achieve both high development adhesion and heat-and-moisture resistance.

The above positive photosensitive siloxane paste is applied onto the substrate on which the color filter layer is formed, and then dried by air drying, heat drying, vacuum drying, etc., and h-line exposure is performed using a photomask and a proximity exposure apparatus. After irradiating an ultraviolet ray of 20 to 300 mJ / cm ² and baking a target pattern, an alkali development is performed to obtain an overcoat layer in a desired pattern at a desired position. After that, by carrying out a bleaching step of irradiating with an ultraviolet ray having an h-ray exposure amount of 50 to 300 mJ / cm ² , the excess sensitizing material originally tinged with yellow is deactivated to obtain a transparent overcoat layer. Can do. Since the sensitizer can be almost deactivated by the next heating step, this bleaching step may be omitted. Finally, by heating at 200 to 300 ° C. for 1 minute to 3 hours, the desensitization of the sensitizer and the curing reaction of the resin are completed to obtain an overcoat layer.

  At this time, the thickness of the planarizing layer is preferably 1.5 μm or more. The reason is that burrs may occur at the end of the colored layer due to stress relaxation when the photoresist is peeled off. To completely fill such burrs, a flattening layer with a thickness of 1.5 μm or more is required. This is because it is necessary. If the burrs are not filled, irregularities due to burrs will remain, resulting in degassing paths and dark spots.

  An anode layer 5 is formed on the overcoat layer 4. Examples of the material for forming the anode layer include metal oxides having transparency and conductivity. Examples of such a metal oxide include indium tin oxide (ITO), indium oxide, zinc oxide, and stannic oxide. Moreover, as a film thickness of a transparent electrode layer, it is about 100 nm-about 300 nm normally. As a method for forming the transparent electrode layer, for example, a method of patterning by photolithography after forming a thin film by vapor deposition or sputtering is preferably used.

  In the configuration of the present invention, the insulating layer 6 is formed to cover the end of the anode layer 5. As a material for forming the insulating layer, for example, a photocurable resin such as a photosensitive polyimide resin or an acrylic resin, a thermosetting resin, an inorganic material, or the like can be used. The pattern of the insulating layer is usually linear, and for example, a pattern having openings such as a matrix shape or a stripe shape is exemplified. Moreover, as a formation method of an insulating layer, the method of apply | coating the said material and patterning by the photolithographic method is mentioned. Also, a printing method or the like can be used.

  In the configuration 1 of the present invention, after the insulating layer 6 is formed, the organic electroluminescence layer 7 is formed on the anode increase 5. The organic electroluminescence layer is an RGB emission type, and the color purity may be further improved by a color filter, but the organic electroluminescence layer is preferably a white emission type.

  The white light emitting layer used in the present invention only needs to be capable of emitting white light. Specifically, as such a white light emitting layer, when a voltage is applied to the organic EL layer, at least blue light (430 nm to 470 nm), green light (470 nm to 600 nm), and red light (600 nm to 600 nm) 700 nm) as long as it has an emission spectrum in the wavelength range, but the green peak in the emission spectrum is the maximum emission intensity of green light (470 nm to 600 nm) and the maximum emission intensity of blue light (430 nm to 470 nm). The ratio to a certain blue peak (green peak / blue peak) is preferably in the range of 0.3 to 0.8, and more preferably in the range of 0.3 to 0.7, In particular, it is preferably within the range of 0.3 to 0.5.

  This is because, when the ratio between the green peak and the blue peak is within the above range, the power consumption reduction effect due to the high transmittance of the green pattern can be more effectively exhibited. For red light (600 nm to 700 nm), the ratio of the maximum emission intensity to the maximum emission intensity of blue light may be within a predetermined range.

  The material constituting the white light emitting layer is not particularly limited as long as it emits fluorescence or phosphorescence. In addition, the light emitting material may have a hole transport property or an electron transport property. Examples of the light emitting material include a dye material, a metal complex material, and a polymer material.

Examples of the dye material include cyclopentamine derivatives, tetraphenylbutadiene derivatives, triphenylamine derivatives, oxadiazol derivatives, pyrazoloquinoline derivatives, distyrylbenzene derivatives, distyrylarylene derivatives, silole derivatives, thiophene ring compounds, pyridine Ring compounds, perinone derivatives, perylene derivatives, oligothiophene derivatives,
Examples thereof include a trifumanylamine derivative, an oxadiazole dimer, and a pyrazoline dimer.

Examples of the metal complex material include an aluminum quinolinol complex, a benzoquinolinol beryllium complex, a benzoxazole zinc complex, a benzothiazole zinc complex, an azomethylzinc complex, a porphyrin zinc complex, a europium complex, or Al, Zn, Be on a central metal.
Or a metal complex having a rare earth metal such as Tb, Eu, or Dy, and having a ligand such as oxadiazole, thiadiazole, phenylpyridine, phenylbenzimidazole, or quinoline structure.

Examples of the polymer material include polyparaphenylene vinylene derivatives, polythiophene derivatives, polyparaphenylene derivatives, polysilane derivatives, polyacetylene derivatives, polyfluorene derivatives, polyvinylcarbazole derivatives, and the above-described dye materials and metal complex materials. Examples thereof include molecularized ones.

Examples of the method for forming the white light emitting layer include a vapor deposition method, a printing method, an inkjet method, a spin coating method, a casting method, a dipping method, a bar coating method, a blade coating method, a roll coating method, a gravure coating method, and a flexographic printing method. , Spray coating, and self-assembly method (alternate adsorption method, self-assembled monolayer method). Among these, it is preferable to use a vapor deposition method, a spin coating method, and an ink jet method.

The thickness of the white light emitting layer used in the present invention is usually about 5 nm to 5 μm.
In the present invention, a hole injection layer may be formed between the white light emitting layer and the anode (transparent electrode layer or back electrode layer). This is because by providing the hole injection layer, the injection of holes into the white light emitting layer is stabilized and the light emission efficiency can be increased.

As a material for forming the hole injection layer used in the present invention, a material generally used for a hole injection layer of an organic EL element can be used. The material for forming the hole injection layer may be any material that has either a hole injection property or an electron barrier property.

Specific examples of the material for forming the hole injection layer include triazole derivatives, oxadiazole derivatives, imidazole derivatives, polyarylalkane derivatives, pyrazoline derivatives, pyrazolone derivatives, phenylenediamine derivatives, arylamine derivatives, amino-substituted chalcone derivatives, oxazole derivatives. And styrylanthracene derivatives, fluorenone derivatives, hydrazone derivatives, stilbene derivatives, silazane derivatives, polysilane-based, aniline-based copolymers, or conductive polymer oligomers such as thiophene oligomers. Furthermore, as a material for forming the hole injection layer, a porphyrin compound, an aromatic tertiary amine compound,
Or a styrylamine compound etc. can be illustrated.

  The thickness of the hole injection layer is usually about 5 nm to 1 μm.

In the present invention, an electron injection layer may be formed between the white light emitting layer and the cathode (transparent electrode layer or back electrode layer). This is because by providing the electron injection layer, the injection of electrons into the white light emitting layer is stabilized, and the light emission efficiency can be increased.

Examples of the material for forming the electron injection layer used in the present invention include heterocyclic tetracarboxylic anhydrides such as nitro-substituted fluorene derivatives, anthraquinodimethane derivatives, diphenylquinone derivatives, thiopyrandioxide derivatives, naphthaleneperylene, carbodiimides, Fluorenylidenemethane derivatives, anthraquinodimethane and anthrone derivatives, oxadiazole derivatives, or thiazole derivatives in which the oxygen atom of the oxadiazole ring of the oxadiazole derivative is substituted with a sulfur atom, quinoxaline known as an electron withdrawing group Examples thereof include quinoxaline derivatives having a ring, metal complexes of 8-quinolinol derivatives such as tris (8-quinolinol) aluminum, phthalocyanine, metal phthalocyanine, or distyrylpyrazine derivatives. The film thickness of the electron injection layer is usually about 5 nm to 1 μm.

After forming the organic electroluminescence layer 7, the cathode layer 8 is formed. Examples of the material for forming the cathode layer include metals, alloys, or mixtures thereof having a work function as small as about 4 eV or less. Specifically, sodium, sodium-potassium alloy, magnesium, lithium, magnesium / copper mixture, magnesium / silver mixture, magnesium / aluminum mixture, magnesium / indium mixture, aluminum / aluminum oxide (Al ₂ O ₃ ) mixture, indium, Or a lithium / aluminum mixture, a rare earth metal, etc. can be illustrated. More preferable examples include a magnesium / silver mixture, a magnesium / aluminum mixture, a magnesium / indium mixture, an aluminum / aluminum oxide (Al ₂ O ₃ ) mixture, or a lithium / aluminum mixture. The cathode layer preferably has a sheet resistance of several Ω / cm or less.

  The film thickness of the cathode is usually about 10 nm to 1 μm.

As the method for forming the cathode layer, for example, a method of forming a thin film by a vapor deposition method or a sputtering method and then patterning by a photolithography method is preferably used.

  After forming the cathode layer 8, the organic electroluminescence element is sealed with a sealant. As a constituent material of such a sealant, any material can be used as long as it can prevent the organic EL element from coming into contact with moisture or the like in the atmosphere, and is generally used for an organic EL display device. Can be used.

  EXAMPLES Hereinafter, although this invention is demonstrated concretely based on an Example, this invention is not limited to these.

Example (Preparation of polyamic acid solution)
Charge 95.1 g of 4,4'-diaminodiphenyl ether and 6.2 g of bis (3-aminopropyl) tetramethyldisiloxane together with 745 g of N-methylpyrrolidone to give 3,3 ', 4,4'-biphenyltetracarboxylic dianhydride 144.1 g of the product was added and reacted at 70 ° C. for 3 hours, then 3.0 g of phthalic anhydride was added, and further reacted at 70 ° C. for 2 hours to obtain a 25 wt% polyamic acid solution (PAA). .

(Synthesis of polymer dispersant)
161.3 g of 4,4′-diaminobenzanilide, 176.7 g of 3,3′-diaminodiphenylsulfone, and 18.6 g of bis (3-aminopropyl) tetramethyldisiloxane were charged together with 3194 g of N-methylpyrrolidone, After adding 439.1 g of 3 ′, 4,4′-biphenyltetracarboxylic dianhydride and reacting at 70 ° C. for 3 hours, 2.2 g of phthalic anhydride was added and further reacted at 70 ° C. for 2 hours. Thus, a polymer dispersant (PD) which is a 20% by weight polyamic acid solution was obtained.

(Preparation of non-photosensitive color paste)
Pigment Red PR254, 3.6 g (80 wt%), Pigment Red PR 177, 0.9 g (20 wt%), 22.5 g of a polymer dispersant (PD) and N-methylpyrrolidone 63 g are charged together with 90 g of glass beads, and a homogenizer is used. After dispersing at 7000 rpm for 5 hours, the glass beads were filtered and removed. In this way, a 5% dispersion (RD) of PR254 and PR177 was obtained.

  Dispersion (RD) 45.6 g, polyamic acid solution (PAA) 18.2 g, 3-aminopropyltriethoxysilane 0.1 g as adhesion improver, acrylic surfactant 0.03 g as surfactant, and An appropriate amount of N-methylpyrrolidone was added and mixed to obtain a red color paste (PR-1) having a pigment / resin ratio of 25/75, a solid content concentration of 6% and NMP as a solvent of 94%. Similarly, a green color containing Pigment Green PG36 and Pigment Yellow PY150 with a weight mixing ratio (G / Y) of 60/40, a pigment / resin ratio of 25/75, a solid content concentration of 6%, and NMP as a solvent of 94%. A blue color paste (PB-1) comprising a paste (PG-1) and pigment blue PB15: 6, having a pigment / resin ratio of 25/75, a solid content concentration of 6%, and NMP as a solvent at 94% was obtained.

(Synthesis of polysiloxane solution)
In a 500 ml three-necked flask, 81.72 g (0.60 mol) of methyltrimethoxysilane, 59.49 g (0.30 mol) of phenyltrimethoxysilane, 24 of (2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane .64 g (0.10 mol) and 163.1 g of DAA were charged, and an aqueous phosphoric acid solution prepared by dissolving 0.54 g of phosphoric acid (0.3 wt% with respect to the charged monomer) in 55.8 g of water while stirring at room temperature After that, the flask was immersed in an oil bath at 40 ° C. and stirred for 30 minutes, and then the oil bath was heated to 115 ° C. over 30 minutes. Then, the mixture was heated and stirred for 1.5 hours (internal temperature was 100 to 110 ° C.) to obtain a polysiloxane solution. 05L (liter) / min shed. Methanol during the reaction by-product, water has issued a total 131g distilled.

The resulting polysiloxane solution had a solid content concentration of 43% by weight, and the polysiloxane had a weight average molecular weight of 4200. The content ratio of phenyl group-substituted silane in the polysiloxane was 30% in terms of Si atom molar ratio.
(Preparation of photosensitive positive transparent resist)
After mixing 15.43 g of the polysiloxane solution obtained in the above synthesis, 0.59 g of the quinonediazide compound obtained in Synthesis Example 7 and 3.73 g of DAA as a solvent and 9.84 g of PGMEA under a yellow light, stirring to obtain a uniform solution The composition 1 was prepared by filtering through a 0.45 μm filter.

(Production of TFT substrate)
A glass substrate (Corning 1737) glass, 100 mm × 100 mm, thickness 0.7 mm was prepared. A TFT substrate was produced from this substrate according to a conventional method.

(Preparation of color filter layer)
The non-photosensitive color paste PR-1 was applied to the TFT substrate with a slit coater and heated on a hot plate at 120 ° C. for 10 minutes to form a semi-cured red resin coating film. Positive type photoresist (Rohm and Haas Electronic Materials, "LC-100A") is applied with a slit coater so that the film thickness after pre-baking is 1.0 μm, and dried on a hot plate at 100 ° C. for 5 minutes. And pre-baked.

Using a UV exposure machine PLA-501F manufactured by Canon Inc., mask exposure was performed at 100 mJ / cm ² (ultraviolet intensity of 365 nm) through a photomask, and then using a 2.0% tetramethylammonium hydroxide aqueous solution, Photoresist development and resin coating etching were simultaneously performed to form a pattern, and then the resist was peeled off with methyl cellosolve acetate. Next, curing was performed by heat treatment in an oven at 270 ° C. for 30 minutes to form a red color filter layer having a thickness of 1.9 μm.

  Similarly, a green color filter layer was formed using the green color paste PG-1, and a blue color filter layer was formed using the blue color paste.

(Evaluation of degassing property of color filter layer)
The amount of gas generated from the color filter layer was measured by temperature programmed desorption-mass spectrometry. The non-photosensitive color paste PR-1 was applied to a glass substrate (0.7 mm) with a slit coater and heated on a hot plate at 120 ° C. for 10 minutes to form a semi-cured R resin coating film. Next, curing was performed by heat-treating in an oven at 270 ° C. for 30 minutes to form an R-colored solid layer having a thickness of 1.9 μm. PG-1 and PB-1 were formed in the same manner.

The produced substrate is cut into 10 mm × 20 mm, and 10 pieces of cut substrates are generated in a helium atmosphere under a helium flow atmosphere of 50 ml / min from room temperature to 300 ° C. under a temperature rising rate of 10 ° C./min. The amount of was quantified. The generated gas was analyzed using a gas chromatography mass spectrometer GC / MS “QP5050A” manufactured by Shimadzu Corporation, and the peak of each gas mass number was determined as the amount of NMP generated. PR-1 total gas generation amount 0.5, moisture 0.4, nitrogen / carbon monoxide / carbon dioxide total amount 0.05, organic gas 0.05 (unit: wtppm / mm ³ ). PG-1 total gas generation amount 0.5, moisture 0.4, nitrogen / carbon monoxide / carbon dioxide total amount 0.05, organic gas 0.05 (unit: wtppm / mm ³ ). PB-1 total gas generation amount 0.5, moisture 0.4, nitrogen / carbon monoxide / carbon dioxide total amount 0.05, organic gas 0.05 (unit: wtppm / mm ³ ). All of the colored layers had good degassing properties.

(Evaluation of heat resistance of color filter layer)
The chromaticity of the color filter layer obtained above was measured using MCPD2000 manufactured by Otsuka Electronics Co., Ltd. Next, the substrate on which the color filter layer was formed was heated in an oven at 240 ° C. for 60 minutes. The chromaticity at the same measurement location as before the heating was measured again with MCPD2000, and the color difference ΔE * ab was determined. The results are shown in Table 1. The color difference before and after heating at 240 ° C. for 60 minutes was 1.0 or less for both RGB, indicating that the heat resistance was good.

(Preparation of overcoat layer)
The composition 1 was spin-coated on the substrate on which the color filter layer was formed using a spin coater (1H-360S manufactured by Mikasa Co., Ltd.) at an arbitrary rotation number, and then hot plate (SCW- manufactured by Dainippon Screen Mfg. Co., Ltd.). 636) for 2 minutes at 90 ° C. to prepare a film having a thickness of 3 μm. Using a parallel light mask aligner (hereinafter abbreviated as PLA) (PLA-501F manufactured by Canon Inc.), the ultra-high pressure mercury lamp was subjected to pattern exposure through a gray scale mask for sensitivity measurement. Using a developing device (AD-2000, manufactured by Takizawa Sangyo Co., Ltd.), shower development was performed for 60 seconds with ELM-D (trade name, manufactured by Mitsubishi Gas Chemical Co., Ltd.) which is a 2.38 wt% tetramethylammonium hydroxide aqueous solution. Then rinsed with water for 30 seconds. After that, as bleaching exposure, PLA (Canon Co., Ltd. PLA-501F) was used, and the entire surface of the film was exposed to 3000 J / m ² (wavelength 365 nm exposure amount conversion) with an ultrahigh pressure mercury lamp.

  After that, soft baking was performed at 110 ° C. for 2 minutes using a hot plate, and then cured in an air at 230 ° C. for 1 hour using an oven (IHPS-222 manufactured by Tabai Espec Co., Ltd.) to prepare a cured film.

(Preparation of anode layer)
On the substrate on which the overcoat layer was formed, a chromium film having a thickness of 0.4 μm was formed by a DC sputtering method, and an ITO film having a thickness of 150 nm was continuously formed by a sputtering method. Next, a photosensitive resist was applied to the entire surface of the ITO film, mask exposure, development, and etching of the ITO film were performed to form a transparent electrode layer. Thereafter, in order to pattern the chromium film, a photosensitive resist was applied on the ITO film and the chromium film, mask exposure, development, and etching of the chromium film were performed to form auxiliary electrodes.

(Formation of insulating layer)
A coating solution for forming an insulating layer was prepared using a polyimide resin (DL1602 manufactured by Toray Industries, Inc.). This insulating layer forming coating solution was applied on the transparent electrode layer by spin coating, and then pre-baked (100 ° C., 5 minutes) to form a resin film having a thickness of 1 μm. Next, mask exposure, development, and post-baking (200 ° C., 30 minutes) were performed to form an insulating layer.

(Preparation of organic electroluminescence layer)
Tris (8-quinolinolato) aluminum (hereinafter abbreviated as Alq3) was deposited on the substrate on which the insulating layer was formed by vacuum deposition as an electron transport layer, and then dicyanomethylenepyran, quinacridone, 4,4 ′ as a light emitting layer on Alq3. A white light emitting layer doped with -bis (2,2-diphenylvinyl) biphenyl was formed. Next, N, N′-diphenyl-N, N′-bis (α-naphthyl) -1,1′-biphenyl-4,4′-diamine was formed into a film by a vacuum evaporation method as a hole transport layer. Finally, ITO was deposited as a transparent electrode by sputtering to form an organic electroluminescence layer having a white light emitting layer.

(Preparation of cathode layer)
Next, magnesium and silver are simultaneously deposited by a vacuum deposition method through a mask having a predetermined opening wider than the display region (magnesium deposition rate = 1.3 nm / second to 1.4 nm).
/ Second, silver deposition rate = 0.1 nm / second). Thus, a 200 nm-thick cathode layer made of magnesium / silver compound was formed on the organic EL layer using the partition walls as a mask.

  Finally, sealing was performed with a color filter substrate in a glow box filled with nitrogen to obtain an organic electroluminescence display device.

(Evaluation of organic electroluminescence display device)
It was turned on in the atmosphere at 85 ° C. for 100 hours, and the presence or absence of dark spots was evaluated. As for the presence or absence of dark spots, those having a diameter of 30 μm or more were recognized as dark spots. The results are shown in Table 1. As a result of evaluation after 100 hours, dark spots could not be confirmed, and the results were good.

Comparative Example A color filter substrate and an image display device were produced in the same manner as in Example 1 except that the curing temperature and the solvent of the colored paste were changed. The results are shown in Table 1. Comparative Example 3
(Preparation of colored paste)
As the coloring paste, a photosensitive color paste containing a pigment, an acrylic resin, a photopolymerization initiator, and a solvent was used. A red photosensitive color paste (AR-1) containing 20% solid content and 80% PMA as a solvent, a green photosensitive color paste (AG-1), and a blue photosensitive color paste (AB-1) were prepared. .

(Preparation of color filter layer)
A red resin coating film pre-baked by applying the red photosensitive color paste AR-1 on a TFT fabrication substrate (Corning, Eagle XG material) with a slit coater and heating on a 90 ° C. hot plate for 10 minutes. Formed. Using a UV exposure machine PLA-501F manufactured by Canon Inc., a mask exposure is performed through a photomask at 100 mJ / cm ² (ultraviolet intensity of 365 nm), followed by development using a 0.05% aqueous potassium hydroxide solution. A pattern was formed. Next, it was cured by heat treatment in an oven at 230 ° C. for 30 minutes to form a red colored layer having a thickness of 1.9 μm.

  Similarly, a green colored layer was formed using the green photosensitive color paste AG-1, and a blue colored layer was formed using the blue photosensitive color paste AB-1.

(Evaluation of degassing property of color filter layer)
In the formation of each colored solid layer, the same operation as in the example was performed except that heat treatment was performed in an oven at 230 ° C. for 30 minutes. Total gas generation amount of AR-1, 4.0, moisture 1.0, nitrogen / carbon monoxide / carbon dioxide total amount 1.0, organic gas 2.0 (unit: wtppm / mm ³ ). AG-1 total gas generation amount 4.0, moisture 1.0, nitrogen / carbon monoxide / carbon dioxide total amount 1.0, organic gas 2.0 (unit: wtppm / mm ³ ). Total gas generation amount of AB-1, 4.0, moisture 1.0, nitrogen / carbon monoxide / carbon dioxide total amount 1.0, organic gas 2.0 (unit: wtppm / mm ³ ). All the colored layers generated a large amount of total gas, and in particular, more organic gas was generated than in the examples.

  Except for the above differences, the heat resistance evaluation of the color filter layer and the production and evaluation of the organic electroluminescence display device were performed in the same manner as in the examples. The results are shown in Table 1. The color difference indicating the heat resistance of the color filter layer was larger than 1.0 for both RGB, and the color difference of the B colored layer was particularly large. In the reliability evaluation of the display device, countless dark spots occurred after 100 hours, and the display performance was poor.

1 ... Glass substrate 2 ... TFT
DESCRIPTION OF SYMBOLS 3 ... Color filter layer 4 ... Overcoat layer 5 ... Anode layer 6 ... Insulating layer 7 ... Organic electroluminescent layer 8 ... Cathode layer 9 ... Sealant 10 ...・ Sealing glass 11 ・ ・ ・ Glass substrate 12 ・ ・ ・ TFT
DESCRIPTION OF SYMBOLS 13 ... Overcoat layer 14 ... Anode layer 15 ... Insulating layer 16 ... Organic electroluminescence layer 17 ... Cathode layer 18 ... Glass substrate 19 ... Light-shielding layer 20 ... Color Filter layer 21 ... Overcoat layer 22 ... Inorganic barrier layer 23 ... Sealant 24 ... Organic electroluminescence element substrate 25 ... Color filter substrate 26 ... Glass substrate 27 ... Light shielding layer 28 ... Color filter layer 29 ... Overcoat layer 30 ... Inorganic barrier layer 31 ... Anode layer 32 ... Insulating layer 33 ... Organic electroluminescence layer 34 ... Cathode layer 35・ ・ ・ Sealing glass 36 ・ ・ ・ Sealing agent

Claims (2)

An organic electroluminescence display device having at least a color filter layer, wherein the resin used in the colored layer constituting the color filter layer is a polyimide resin. 2. The organic electroluminescence display device according to claim 1, further comprising a TFT for driving an organic electroluminescence display element, wherein the color filter layer is formed on the same substrate as the TFT.

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