JP2007157738A - Evacuation light - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an evacuation light suitably used even under high temperature in which light emission efficiency is high, power consumption is lower than before, and thermal resistance is especially high. <P>SOLUTION: The evacuation light comprises an organic electroluminescence element where an anode 2, a light emitting layer 4, and a cathode 6 are laminated in this order and equipped with a means for displaying a predetermined shape. The light emitting layer is composed of an organic material containing 50 wt.% or more of high molecular compound and performs phosphorescence light emission. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an evacuation guide lamp using an organic electroluminescence (hereinafter also referred to as “organic EL”) element.

  Various evacuation guide lights for displaying emergency exits and the like have been used conventionally. For example, conventional evacuation guide lights include evacuation guide lights that use neon tubes arranged according to characters and patterns, and evacuation guides that illuminate with fluorescent lights from the back of a translucent plastic board depicting characters and patterns. There is a light.

However, in the conventional example using a neon tube, since one neon tube itself has a predetermined size, there is a problem that the thickness and size of the entire display device are required.
Moreover, in the type of evacuation guide light that irradiates the design printed on the plastic plate from the back with a fluorescent lamp, there is a problem that the thickness is required to some extent and the visibility is low.

In order to solve such problems, evacuation guide lights using organic EL elements have also been proposed.
That is, the evacuation guide lamp described in Japanese Patent Application Laid-Open No. 2001-013898 (Patent Document 1) uses an organic EL element as a light source instead of a fluorescent lamp in order to reduce the thickness. However, in this display method of illuminating a printed pattern with an organic EL element, (1) the pattern becomes dark. (2) If the light emission luminance of the organic EL element is increased to make it brighter, the life of the organic EL element is shortened. There were shortcomings such as shortening. Further, this display method has a problem that visibility is deteriorated particularly in an environment filled with smoke due to fire or the like because the clearness of the image which is a characteristic of the organic EL element is lost.

Japanese Patent Application Laid-Open No. 2001-265270 (Patent Document 2) describes a display device in which a plurality of pixels are formed by organic EL elements and a pattern is displayed by these pixels. However, since this display device uses a fluorescent polymer material as the light emitting material, (1) it is difficult to use it as an evacuation guide light that is always lit, since the external quantum efficiency of light emission is low, (2) There is a problem that it is difficult to use as an evacuation guide light because the life is short under a high temperature condition such as a fire exceeding a normal environmental temperature.
JP 2001-013898 A JP 2001-265270 A

The present invention has been made in view of such problems of the prior art, and an object of the present invention is to provide an evacuation guide light having high luminous efficiency and lower power consumption than the conventional one.
Another object of the present invention is to provide an evacuation guide light that is particularly high in heat resistance and can be suitably used even at high temperatures in the event of a fire or the like.

  The present inventors have intensively studied to solve the above problems and completed the present invention. The present invention relates to the following [1] to [18].

[1] An evacuation guide lamp including an organic electroluminescence element in which an anode, a light emitting layer, and a cathode are stacked in this order, and a means for displaying a predetermined shape,
An evacuation guide lamp, wherein the light emitting layer is made of an organic material containing 50% by weight or more of a polymer compound and emits phosphorescence.

  [2] The evacuation guide light according to [1], wherein the means for displaying the predetermined shape is a plurality of the organic electroluminescence elements arranged in the same shape as the predetermined shape.

  [3] The evacuation guide light according to [1], wherein the means for displaying the predetermined shape is the anode and / or the cathode formed in the same shape as the predetermined shape.

  [4] The evacuation guide light according to [1], wherein the means for displaying the predetermined shape is the light emitting layer formed in the same shape as the predetermined shape.

  [5] The evacuation guide light according to any one of [1] to [4], wherein the polymer compound is a phosphorescent polymer compound.

  [6] The evacuation guide light according to any one of [1] to [5], wherein the organic material contains only a phosphorescent polymer compound.

[7] Any one of [1] to [6] above, wherein the phosphorescent polymer compound has a polystyrene-reduced weight average molecular weight of 10 ⁵ or more as measured by GPC (gel permeation chromatography). The evacuation guide light described in Crab.

  [8] The evacuation guide light according to any one of [1] to [7], wherein the phosphorescent polymer compound is produced by radical polymerization of a phosphorescent compound and a charge transporting compound. .

  [9] The evacuation guide light according to [8] above, wherein at least a part of the phosphorescent compound is a phosphorescent iridium complex represented by the following formula (1):

[In Formula (1), R < ¹ > -R < ⁸ > is respectively independently a hydrogen atom, a halogen atom, a cyano group, a C1-C10 alkyl group, a C6-C10 aryl group, and C1-C10. Represents an atom or substituent selected from the group consisting of an amino group optionally substituted by an alkyl group, an alkoxy group having 1 to 10 carbon atoms, and a silyl group, and may be bonded to each other to form a condensed ring. .

  L is one ligand selected from the ligands represented by the following formulas (2) to (4).

(In the formula (2), R ¹¹ ~R ¹⁸ are each independently a hydrogen atom, a halogen atom, a cyano group, an alkyl group having 1 to 10 carbon atoms, an aryl group having 6 to 10 carbon atoms, 1 to 10 carbon atoms Represents an atom or substituent selected from the group consisting of an amino group optionally substituted by an alkyl group, an alkoxy group having 1 to 10 carbon atoms, and a silyl group, and may be bonded to each other to form a condensed ring. ,
At least one of R ^{11 to} R ¹⁸ represents a substituent having a polymerizable functional group. ),

(In the formula (3), R ²¹ ~R ²³ independently represents a hydrogen atom, a cyano group, an alkyl group having 1 to 10 carbon atoms, an aryl group having 6 to 10 carbon atoms, alkyl group having 1 to 10 carbon atoms Represents an atom or a substituent selected from the group consisting of an amino group optionally substituted by, an alkoxy group having 1 to 10 carbon atoms, and a silyl group, and may be bonded to each other to form a condensed ring;
At least one of R ^{21 to} R ²³ represents a substituent having a polymerizable functional group. ),

(In formula (4), R ^{31 to} R ³⁴ are each independently a hydrogen atom, a halogen atom, a cyano group, an alkyl group having 1 to 10 carbon atoms, an aryl group having 6 to 10 carbon atoms, or 1 to 10 carbon atoms. Represents an atom or substituent selected from the group consisting of an amino group optionally substituted by an alkyl group, an alkoxy group having 1 to 10 carbon atoms, and a silyl group, and may be bonded to each other to form a condensed ring. ,
At least one of R ^{31 to} R ³⁴ represents a substituent having a polymerizable functional group. ]].

  [10] The evacuation guide light according to any one of [1] to [9], wherein the organic electroluminescence device has an emission external quantum efficiency of 5.0% or more.

[11] In the above [1] to [10], the front luminance of the light emitting region of the predetermined shape is 1000 cd / m ² or more when a current of 5 mA / cm ² is passed through the predetermined shape. The evacuation guide light described in any one.

[12] When the evacuation guide lamp is energized so that the front luminance of the light emitting area of the predetermined shape is 1000 cd / m ^2, and the light is emitted in the atmosphere of 100 ° C. while maintaining the current value at this time, The evacuation guide light according to any one of [1] to [11] above, wherein the time until the front luminance decreases to 500 cd / m ² is 100 hours or more.

  [13] The evacuation guide light according to any one of [1] to [12], wherein a light emission color of the light emitting layer is an arbitrary single color.

  [14] The evacuation guide light according to any one of [1] to [13], wherein the predetermined shape includes a green light emitting region and a light emitting region of another color.

  [15] The evacuation guide light according to any one of [1] to [14], wherein the organic electroluminescence element is formed on a plastic substrate or a plastic film substrate.

  [16] The evacuation guide light according to any one of [1] to [15], wherein the predetermined shape is controlled to repeat lighting and non-lighting at regular time intervals.

  [17] The escape guide light according to any one of [1] to [16], wherein the predetermined shape is displayed on both the anode side and the cathode side of the escape guide lamp.

  [18] The evacuation guide light according to any one of [1] to [17], wherein the predetermined shape is a moving image.

The evacuation guide lamp of the present invention has high luminous efficiency and can suppress power consumption as compared with the conventional case.
Furthermore, since the evacuation guide lamp of the present invention has higher heat resistance and longer driving life than an evacuation guide lamp whose light-emitting layer is made of a fluorescent light-emitting polymer compound, it is preferably used even at high temperatures (for example, 80 to 150 ° C.). can do.

  The evacuation guide lamp of the present invention is an evacuation guide lamp that includes an organic EL element in which an anode, a light emitting layer, and a cathode are laminated in this order, and includes a means for displaying a predetermined shape. It is made of an organic material containing 50% by weight or more of a polymer compound and is characterized by phosphorescence.

[Organic EL device]
<1. Anode>
The anode is formed of a conductive and light transmissive layer typified by ITO. When observing organic light emission through the substrate described later, the light transmittance of the anode is essential, but in the case of the application of observing the organic light emission through the top emission, that is, the upper electrode, the anode permeability is not necessary, Any suitable material such as a metal or metal compound with a function higher than 4.1 eV can be used as the anode. For example, gold, nickel, manganese, iridium, molybdenum, palladium, platinum, or the like can be used alone or in combination. The anode can also be selected from the group consisting of metal oxides, nitrides, selenides and sulfides. In addition, a thin film having a thickness of 1 to 3 nm formed on the surface of ITO having good light transmittance so as not to impair the light transmittance can be used as an anode. As a film formation method on the surface of these anode materials, an electron beam evaporation method, a sputtering method, a chemical reaction method, a coating method, a vacuum evaporation method, or the like can be used. The thickness of the anode is 2-30
0 nm is preferable.

<2. Element Configuration>
FIG. 1 is a cross-sectional view showing an example of the configuration of an organic EL device used in the present invention, in which a hole transport layer, a light emitting layer, and an electron transport layer are sequentially provided between an anode and a cathode provided on a transparent substrate. It is.
Further, the configuration of the organic EL device used in the present invention is not limited to the example of FIG. 1, and 1) anode buffer layer / hole transport layer / light emitting layer, 2) anode buffer layer / Light-emitting layer / electron transport layer, 3) anode buffer layer / hole transport layer / light-emitting layer / electron transport layer, 4) anode buffer layer / hole transport compound, light-emitting compound, layer containing electron transport compound, 5 ) Anode buffer layer / hole transporting compound, layer containing luminescent compound, 6) Anode buffer layer / luminescent compound, layer containing electron transporting compound, 7) Anode buffer layer / hole electron transporting compound, luminescence A layer containing a conductive compound, and 8) an element configuration provided with an anode buffer layer / light emitting layer / hole blocking layer / electron transport layer. Further, although the light emitting layer shown in FIG. 1 is a single layer, it may have two or more light emitting layers. Furthermore, the layer containing a hole transporting compound may be in direct contact with the surface of the anode without using the anode buffer layer.

  In the present specification, unless otherwise specified, a compound composed of all or one of an electron transporting compound, a hole transporting compound, and a light emitting compound is an organic EL compound, and a layer is an organic EL compound layer. I will call it.

<3. Anode surface treatment>
In addition, the performance of the layer to be overcoated by pre-treating the anode surface during the formation of the anode buffer layer or the layer containing the hole transporting compound (adhesion with the anode, surface smoothness, hole injection barrier) , Etc.) can be improved. Examples of the pretreatment method include high-frequency plasma treatment, sputtering treatment, corona treatment, UV ozone irradiation treatment, and oxygen plasma treatment.

<4. Anode buffer layer>
When the anode buffer layer is produced by applying a wet process, spin coating, casting, micro gravure coating, gravure coating, bar coating, roll coating, wire bar coating, dip coating, The film can be formed by using a coating method such as a spray coating method, a screen printing method, a flexographic printing method, an offset printing method, and an ink jet printing method.

  The compound that can be used in the film formation by the wet process is not particularly limited as long as it is a compound having good adhesion to the organic EL compound contained in the anode surface and its upper layer, but the anode buffer that has been generally used so far Is more preferable. Examples thereof include conductive polymers such as a mixture of poly (3,4-ethylenedioxythiophene) and polystyrene sulfonic acid (PEDOT-PSS), polyaniline, and a mixture of polyaniline and polystyrene sulfonic acid. Further, an organic solvent such as toluene or isopropyl alcohol may be added to these conductive polymers. Moreover, the conductive polymer containing 3rd components, such as surfactant, may be sufficient. The surfactant is, for example, selected from the group consisting of alkyl groups, alkylaryl groups, fluoroalkyl groups, alkylsiloxane groups, sulfates, sulfonates, carboxylates, amides, betaine structures, and quaternized ammonium groups. Surfactants containing one kind of group are used, but fluoride-based nonionic surfactants can also be used.

<5. Organic EL compound>
Of the organic EL compound layers in the organic EL device used in the present invention, as the compound used for the hole transport layer and the electron transport layer, either a low molecular compound or a high molecular compound can be used.

  The light emitting layer of the organic EL element used in the present invention is phosphorescent and is formed from an organic material containing 50% by weight or more of a polymer compound. The polymer compound is preferably a phosphorescent polymer compound, and the organic material is particularly preferably composed of only a phosphorescent polymer compound. Since the evacuation guide lamp of the present invention is made of such an organic material, it has high luminous efficiency and excellent heat resistance.

  The polymer compound preferably has carrier transport properties, and more preferably has carrier transport properties and phosphorescence. Examples of the polymer compound having a carrier transport property include TPD (N, N′-dimethyl-N, N ′-(3-methylphenyl) -1,1′-biphenyl-4,4′diamine), α- NPD (4,4′-bis [N- (1-naphthyl) -N-phenylamino] biphenyl), m-MTDATA (4,4 ′, 4 ″ -tris (3-methylphenylphenylamino) triphenylamine ) And the like, which are polymerized by introducing a polymerizable functional group into the polymer, such as a polymer compound disclosed in JP-A-8-157575, polyvinylcarbazole, polyparaphenylene vinylene, polyalkyl Fluorenes and the like, and quinolinol derivative metal complexes such as Alq3 (aluminum triskinolinolate), Polymers obtained by introducing polymerizable functional groups into low molecular compounds having electron transport properties such as azole derivatives, triazole derivatives, imidazole derivatives, triazine derivatives, and triarylborane derivatives, for example, disclosed in JP-A-10-1665 And known high molecular compounds such as poly PBD, copolymers of compounds obtained by introducing polymerizable functional groups into the low molecular weight compounds, such as the high molecular compounds disclosed in Japanese Patent Application Laid-Open No. 2005-00638. It is done.

The phosphorescent polymer compound preferably has a polystyrene-reduced weight average molecular weight of 10 ⁵ or more as measured by GPC (gel permeation chromatography). When the molecular weight is in such a range, the heat resistance of the organic EL device used in the present invention is particularly excellent. As a result, the evacuation guide lamp of the present invention has an evacuation guide lamp in which the light emitting layer is made of a fluorescent light emitting polymer compound. In addition, it has higher heat resistance and a longer driving life, and can be suitably used even at high temperatures.

  The light emitting layer in the organic light emitting device used in the present invention contains at least a phosphorescent compound, and preferably includes a phosphorescent unit that emits phosphorescence and a carrier transport unit that transports carriers in one molecule. And at least a phosphorescent polymer. The phosphorescent polymer can be obtained by copolymerizing a phosphorescent compound having a polymerizable substituent and a carrier transporting compound having a polymerizable substituent. The phosphorescent compound is a metal complex containing a metal element selected from rhenium, ruthenium, osmium, rhodium, iridium, palladium, platinum and gold, and among them, an iridium complex is preferable.

  Examples of the low molecular weight phosphorescent compound include metal complexes represented by the following formulas (E-1) to (E-49).

In the above formulas (E-35) and (E-46) to (E-49), Ph represents a phenyl group.
Preferred examples of the phosphorescent compound having a polymerizable substituent include compounds in which one or more hydrogen atoms of the phosphorescent iridium complex represented by the following formula (1) are substituted with a polymerizable substituent. Can do.

[In Formula (1), R < ¹ > -R < ⁸ > is respectively independently a hydrogen atom, a halogen atom, a cyano group, a C1-C10 alkyl group, a C6-C10 aryl group, and C1-C10. Represents an atom or substituent selected from the group consisting of an amino group optionally substituted by an alkyl group, an alkoxy group having 1 to 10 carbon atoms, and a silyl group, which are bonded to each other to form a condensed ring. Also good.

As said halogen atom, a fluorine atom, a chlorine atom, a bromine atom, or an iodine atom is mentioned.
Examples of the alkyl group having 1 to 10 carbon atoms include methyl group, ethyl group, propyl group, isopropyl group, butyl group, isobutyl group, t-butyl group, amyl group, hexyl group, octyl group, and decyl group. Can be mentioned.

Examples of the aryl group having 6 to 10 carbon atoms include a phenyl group, a tolyl group, a xylyl group, a mesityl group, and a naphthyl group.
Examples of the amino group that may be substituted with the alkyl group having 1 to 10 carbon atoms include an amino group, a dimethylamino group, a diethylamino group, and a dibutylamino group.

  Examples of the alkoxy group having 1 to 10 carbon atoms include a methoxy group, an ethoxy group, a propoxy group, an isopropoxy group, a butoxy group, an isobutoxy group, a t-butoxy group, a hexyloxy group, a 2-ethylhexyloxy group, and a decyloxy group. Etc.

Examples of the silyl group include a trimethylsilyl group, a triethylsilyl group, a t-butyldimethylsilyl group, and the like.
Among these, the production of the iridium complex monomer is easy, and the solubility of the complex in the solvent and the control of the emission wavelength are easy. Alkyl group, phenyl group, tolyl group, dimethylamino group, and alkoxy group having 1 to 4 carbon atoms are preferable, and since the production of the iridium complex monomer is particularly easy, a hydrogen atom, a fluorine atom, a t-butyl group More preferred are a dimethylamino group and a methoxy group.

  L is one ligand selected from the ligands represented by the following formulas (2) to (4).

(In formula (2), R ^{11 to} R ¹⁸ are each independently the same atom or group as R ^{1 to} R ^8, and may be bonded to each other to form a condensed ring;
At least one of R ^{11 to} R ¹⁸ represents a substituent having a polymerizable functional group. ),

(In formula (3), R ^{21 to} R ²³ are each independently the same atom (excluding a halogen atom) or group as R ^{1 to} R ^8, and bonded to each other to form a condensed ring. May form,
At least one of R ^{21 to} R ²³ represents a substituent having a polymerizable functional group. ),

(In Formula (4), R ^{31 to} R ³⁴ are each independently the same atom or group as R ^{1 to} R ^8, and may be bonded to each other to form a condensed ring;
At least one of R ^{31 to} R ³⁴ represents a substituent having a polymerizable functional group. )]

  Examples of polymerizable substituents in these phosphorescent compounds include urethane (meth) acrylate groups such as vinyl groups, acrylate groups, methacrylate groups, methacryloyloxyethyl carbamate groups, styryl groups and derivatives thereof, vinylamide groups and derivatives thereof, and the like. Among them, vinyl group, methacrylate group, styryl group and derivatives thereof are preferable. These substituents may be bonded to the metal complex via an organic group having 1 to 20 carbon atoms which may have a hetero atom.

  The carrier transporting compound having a polymerizable substituent is a compound in which one or more hydrogen atoms in an organic compound having one or both of a hole transporting property and an electron transporting property are substituted with a polymerizable substituent. Can be mentioned. As typical examples of such a compound, compounds represented by the following formulas (E-50) to (E-67) can be given.

  In these exemplified carrier transporting compounds, the polymerizable substituent is a vinyl group. The vinyl group is a urethane (meth) acrylate group such as an acrylate group, a methacrylate group, or a methacryloyloxyethyl carbamate group, a styryl group and a derivative thereof, and a vinylamide. It may be a compound substituted with a polymerizable substituent such as a group or a derivative thereof. Further, these polymerizable substituents may be bonded via an organic group having 1 to 20 carbon atoms which may have a hetero atom.

The polymerization method of the phosphorescent compound having a polymerizable substituent and the carrier transporting compound having a polymerizable substituent may be any of radical polymerization, cationic polymerization, anionic polymerization and addition polymerization, but radical polymerization is preferred. The molecular weight of the polymer is preferably 10,000 to 2,000,000 in terms of weight average molecular weight, more preferably 50,000 to 1,000,000, and particularly preferably 100,000 to 500,000. The molecular weight here is a molecular weight in terms of polystyrene measured using a GPC (gel permeation chromatography) method.

  The phosphorescent polymer may be a copolymer of one phosphorescent compound and one carrier transporting compound, one phosphorescent compound and two or more carrier transporting compounds. One or more phosphorescent compounds may be copolymerized with a carrier transporting compound.

  The arrangement of the monomer in the phosphorescent polymer may be any of random copolymer, block copolymer, and alternating copolymer, the number of repeating units of the phosphorescent compound structure is m, and the repeating unit of the carrier transporting compound structure When the number is n (m, n is an integer of 1 or more), the ratio of the number of repeating units of the phosphorescent compound structure to the total number of repeating units, that is, the value of m / (m + n) is preferably 0.001 to 0.5, 0.001 -0.2 is more preferable.

  More specific examples and synthesis methods of phosphorescent polymers are disclosed in, for example, JP2003-342325, JP2003-119179, JP2003-113246, JP2003-206320, JP2003-147021, and JP2003. -171391, JP-A-2004-346312, and JP-A-2005-97589.

  The light emitting layer in the organic EL device used in the present invention is preferably a layer containing the phosphorescent compound, but includes a hole transporting compound or an electron transporting compound for the purpose of supplementing the carrier transporting property of the light emitting layer. It may be. As the hole transporting compound used for these purposes, for example, TPD (N, N′-dimethyl-N, N ′-(3-methylphenyl) -1,1′-biphenyl-4,4′diamine) is used. , Α-NPD (4,4′-bis [N- (1-naphthyl) -N-phenylamino] biphenyl), m-MTDATA (4,4 ′, 4 ″ -tris (3-methylphenylphenylamino) Low molecular triphenylamine derivatives such as triphenylamine), polyvinyl carbazole, and polymers obtained by introducing a polymerizable functional group into the triphenylamine derivative, for example, disclosed in JP-A-8-157575 Examples include a polymer compound having a triphenylamine skeleton, polyparaphenylene vinylene, polydialkylfluorene, and the like. For example, low molecular materials such as quinolinol derivative metal complexes such as Alq3 (aluminum triskinolinolate), oxadiazole derivatives, triazole derivatives, imidazole derivatives, triazine derivatives, triarylborane derivatives, and the above low molecular electron transport compounds For example, a known electron transporting compound such as poly PBD disclosed in JP-A-10-1665 can be used.

<6. Formation Method of Organic EL Compound Layer>
The organic EL compound layer is formed by resistance heating vapor deposition, electron beam vapor deposition, sputtering, spin coating, casting, micro gravure coating, gravure coating, bar coating, roll coating, wire bar coating, It can be formed by a coating method such as a dip coating method, a spray coating method, a screen printing method, a flexographic printing method, an offset printing method, and an ink jet printing method. In the case of luminescent low molecular weight compounds, resistance heating vapor deposition and electron beam vapor deposition are mainly used, and in the case of luminescent high molecular weight compounds, mainly spin coating method, casting method, micro gravure coating method, gravure coating method, bar coating method. Coating methods such as a method, a roll coating method, a wire bar coating method, a dip coating method, a spray coating method, a screen printing method, a flexographic printing method, an offset printing method, and an inkjet printing method are used.

<7. Hole blocking layer>
Further, a hole blocking layer may be provided adjacent to the cathode side of the light emitting layer for the purpose of suppressing the passage of holes through the light emitting layer and efficiently recombining with electrons in the light emitting layer. For this hole blocking layer, a compound having a lower highest occupied molecular orbital (HOMO) energy level than the luminescent compound can be used, and triazole derivatives, oxadiazole derivatives, phenanthroline derivatives, aluminum complexes, It can be illustrated.

  Furthermore, an exciton block layer may be provided adjacent to the cathode side of the light emitting layer for the purpose of preventing excitons (excitons) from being deactivated by the cathode metal. For this exciton block layer, a compound having a larger excitation triplet energy than the light-emitting compound can be used, and examples thereof include triazole derivatives, phenanthroline derivatives, and aluminum complexes.

<8. Cathode>
As a cathode material of the organic EL device used in the present invention, a material having a low work function and a chemically stable material is used, and known Al, MgAg alloys, Al and alkali metal alloys such as AlLi and AlCa are known. A cathode material can be exemplified, but the work function is preferably 2.9 eV or more in consideration of chemical stability. As a film forming method of these cathode materials, a resistance heating vapor deposition method, an electron beam vapor deposition method, a sputtering method, an ion plating method, or the like can be used. The thickness of the cathode is preferably 10 nm to 1 μm, and more preferably 50 to 500 nm.

In addition, a metal layer having a lower work function than the cathode is inserted between the cathode and the organic layer adjacent to the cathode as a cathode buffer layer in order to lower the electron injection barrier from the cathode to the organic layer and increase the efficiency of electron injection. May be. Low work function metals that can be used for such purposes include alkali metals (Na, K, Rb, Cs), alkaline earth metals (Sr, Ba, Ca, Mg), rare earth metals (Pr, Sm, Eu, Yb) and the like. An alloy or a metal compound can also be used as long as it has a work function lower than that of the cathode. As a method for forming these cathode buffer layers, vapor deposition, sputtering, or the like can be used. The thickness of the cathode buffer layer is preferably 0.05 to 50 nm, more preferably 0.1 to 20 nm, and 0.5 to 1
0 nm is even more preferable.

  Further, the cathode buffer layer can be formed as a mixture of the low work function substance and the electron transporting compound. In addition, as an electron transport compound used here, the organic compound used for the above-mentioned electron transport layer can be used. In this case, a co-evaporation method can be used as a film forming method. In addition, in the case where coating film formation using a solution is possible, the above-described film formation methods such as a spin coating method, a dip coating method, an ink jet method, a printing method, a spray method, and a dispenser method can be used. In this case, the thickness of the cathode buffer layer is preferably from 0.1 to 100 nm, more preferably from 0.5 to 50 nm, and even more preferably from 1 to 20 nm. Between the cathode and the organic material layer, a layer made of a conductive polymer or a layer made of a metal oxide, metal fluoride, organic insulating material or the like having an average film thickness of 2 nm or less may be provided.

<9. Sealing>
A protective layer for protecting the organic EL element may be attached after the cathode is produced. In order to use the organic EL element stably for a long period of time, it is preferable to attach a protective layer and / or a protective cover in order to protect the element from the outside. As the protective layer, a polymer compound, metal oxide, metal fluoride, metal boride and the like can be used. As the protective cover, a glass plate, a plastic plate with a low water permeability treatment on the surface, a metal, or the like can be used, and the cover is bonded to the element substrate with a thermosetting resin or a photocurable resin and sealed. Is preferably used. If a space is maintained using a spacer, it is easy to prevent the element from being damaged. If an inert gas such as nitrogen or argon is sealed in the space, the cathode can be prevented from being oxidized, and moisture adsorbed in the manufacturing process by installing a desiccant such as barium oxide in the space. It becomes easy to suppress giving an image to an element. Of these, it is preferable to take one or more measures.

<10. Substrate type>
As the substrate of the organic EL device according to the present invention, an insulating substrate transparent to the emission wavelength of the luminescent compound, for example, glass, transparent plastics such as PET (polyethylene terephthalate) and polycarbonate, silicon substrates, etc. are known. Can be used.

Such an organic EL device used in the present invention has a high light-emitting external quantum efficiency, and the value thereof is 5.0% or more, preferably 7.0% or more.
[Predetermined shape display means]
In the evacuation guide light of the present invention, the predetermined shape is displayed by a specific means. Here, the predetermined shape may be a figure or a character, and an example thereof is a figure as shown in FIG.

As the first specific means, a plurality of the organic EL elements arranged in the same shape as a predetermined shape to be displayed (that is, a shape to be displayed by the evacuation guide light of the present invention) may be mentioned.
The display of the predetermined shape by such means is to control the driving conditions (current values, etc.) of the plurality of organic EL elements in one predetermined shape, respectively, thereby displaying the light and darkness (floor) of the display within the predetermined shape. This is preferable in that the tone display) can be controlled. Further, by controlling the driving conditions of the plurality of organic EL elements in one predetermined shape, the predetermined shape can be made into a moving image.

  As a second specific means, the anode (hereinafter also referred to as “predetermined shape anode”) and / or the cathode (hereinafter also referred to as “predetermined shape cathode”) formed in the same shape as the predetermined shape to be displayed. .).

  By displaying the predetermined shape by such means, the image is particularly clear, the electrode area is large, and high luminance is obtained at a relatively low current density, so that the durability of the organic EL element is also particularly high. This is preferable.

Here, when the predetermined shape is displayed by the anode having the predetermined shape, the anode may be formed by the following method, for example.
First, a photoresist material is applied to the surface of the anode, and a desired shape is irradiated with light. Subsequently, the portion of the photoresist material not irradiated with light is removed, and the anode material in this portion is removed with an etching solution. Finally, an anode having a predetermined shape can be formed by removing the photoresist material in the portion irradiated with light.

Moreover, when displaying a predetermined shape with a cathode having a predetermined shape, the cathode may be formed by the following method, for example.
That is, a cathode having a predetermined shape can be formed by placing a mask with a hole in a predetermined shape on the organic EL compound layer and forming a cathode material thereon by a method such as coating or vapor deposition. it can.

As the third specific means, the light emitting layer having the same shape as the predetermined shape (hereinafter also referred to as “predetermined light emitting layer”) may be mentioned.
Since a light emitting layer having a predetermined shape can be formed simply by applying a light emitting layer forming material or a solution containing this material in a predetermined shape, the predetermined shape is displayed by such means (third specific means). This is preferable in that a light emitting layer having a predetermined shape can be easily manufactured, and even a light emitting layer having a fine shape can be easily formed.

When the predetermined shape is displayed by the light emitting layer having the predetermined shape, the light emitting layer may be formed by the following method, for example.
Spin coating method, casting method, micro gravure coating method, gravure coating method, bar coating method, roll coating method, wire bar coating method, dip coating method, spray coating method, screen printing method, flexographic printing method, offset printing method By applying a polymer light emitting material by a method such as an ink jet printing method, a light emitting layer having a predetermined shape can be formed. Also, since the conditions such as the viscosity of the solution to be used vary depending on the coating method, the preferred molecular weight of the polymer material varies depending on the coating method, but if the molecular weight of the polymer material is large (for example, 10 ⁵ or more), the predetermined shape after coating This is preferable in that bleeding and the like are suppressed.

[Evacuation guide light]
The evacuation guide lamp of the present invention includes the organic EL element and means for displaying the predetermined shape, and is provided with wiring, a control circuit, and the like by a conventional method.

The evacuation guide lamp of the present invention has high luminance, and when a current of 5 mA / cm ² is passed through the predetermined shape, the luminance in front of the light emitting region of the predetermined shape is 800 cd / m ² or more, preferably 1
000 cd / m ² or more.

Here, “a current of 5 mA / cm ² flows in a predetermined shape” means that the means for displaying the predetermined shape is a plurality of the organic EL elements arranged in the same shape as the predetermined shape. Is to flow a current of 5 mA per unit area (1 cm ² ) of the organic EL element, and when the means for displaying the predetermined shape is the anode, cathode or light emitting layer of the predetermined shape, Current of 5 mA per unit area (1 cm ² ) of the anode, the cathode or the light emitting layer.

  In addition, the “front luminance of the light emitting area” is not the front luminance of the entire surface of the evacuation guide light according to the present invention, but only the light emitting area (also referred to as “7” in FIG. 2) on the surface of the evacuation guide light. Is the front brightness. Therefore, the non-light emitting region (8 in FIG. 2, also referred to as “non-light emitting portion”) is not considered.

The evacuation guide lamp of the present invention can maintain high brightness over a long period of time even at high temperatures. For example, when the evacuation guide lamp is energized so that the front luminance of the light emitting area is 1000 cd / m ² and is emitted in the atmosphere of 100 ° C. while maintaining the current value at this time, the front luminance is The time to decrease to 500 cd / m ² is 100 hours or longer, preferably 200 hours or longer.

In the escape guide lamp of the present invention, the emission color of the light emitting layer may be any single color, preferably green. Any single color is preferable from the viewpoint of ease of production.
It may consist of two colors including green.

  The predetermined shape may be composed of a green light emitting region and a light emitting region of another color, preferably a green light emitting region and a white light emitting region. In particular, green and white are preferable because the evacuation guide light of the present invention is easily visible. The predetermined shape of such a form is achieved by providing a light emitting layer (green light emitting region 9) made of a green light emitting material and a light emitting layer (white light emitting region 10) made of a white light emitting material, as shown in FIG. it can.

In the evacuation guide light of the present invention, the predetermined shape may be controlled so as to repeat lighting and non-lighting at regular time intervals.
If the anode is made of a transparent material, a predetermined shape can be displayed on the substrate-side surface of the evacuation guide lamp of the present invention. If the cathode is made of a transparent material, the substrate of the evacuation guide lamp of the present invention can be displayed. Can display a predetermined shape on the opposite surface.

  In addition, since the organic EL element used in the present invention is self-luminous, if the escape guide lamp of the present invention includes a transparent or translucent anode and cathode, a predetermined shape can be displayed on both sides thereof. .

[Example]
EXAMPLES Hereinafter, although this invention is demonstrated in detail based on an Example, this invention is not limited to this.

  Poly (3,4-ethylenedioxythiophene) / polystyrene sulfonic acid is applied on a glass substrate of 100 mm square on which an ITO (indium tin oxide) electrode (anode) is formed on the surface with a rotation speed of 3500 rpm and a coating time of 40 seconds. The coating was performed by a spin coating method under the conditions. Then, it dried for 2 hours at 60 degreeC under pressure reduction with the vacuum dryer, and formed the anode buffer layer. The film thickness of the obtained anode buffer layer was about 50 nm.

  Next, a 3% toluene solution of poly (methyl methacrylate) was applied by spin coating under the conditions of a rotation speed of 3000 rpm and an application time of 30 seconds. After coating, the film was dried at 60 ° C. for 2 hours under reduced pressure in a vacuum dryer to form an insulating layer. The film thickness of the obtained insulating layer was about 50 nm.

  Next, a 1% toluene solution of the phosphorescent polymer (I) was applied on the insulating layer on a pattern (see FIG. 2) displayed by a screen printing method. After the application, it was dried at room temperature (25 ° C.) for 30 minutes to form a light emitting layer. The film thickness of the obtained light emitting layer was about 100 nm.

Next, the substrate on which the light emitting layer was formed was placed in a vapor deposition apparatus. Next, calcium and aluminum were co-evaporated at a weight ratio of 1:10 to form a cathode having a thickness of about 50 nm.
Wiring was attached to the organic EL element having the light emitting layer having a predetermined shape thus formed according to a conventional method to produce an evacuation guide lamp.

When the manufactured escape guide lamp was supplied with a current of 5 mA / cm ² with respect to the area of the light emitting part (light emitting layer), the front luminance of the light emitting part was 1300 cd / m ² . Further, energization was performed so that the front luminance of the light emitting part of the evacuation guide light was 1000 cd / m ^2, and the current value was kept 1
When placed in a high-temperature bath at 00 ° C., the time until the luminance reached 500 cd / m ² was 250 hours.

FIG. 1 shows a basic structure of an organic EL element used in the present invention. FIG. 2 shows the shape of the light emitting layer of the evacuation guide lamp manufactured in the example. FIG. 3 shows an example of a shape displayed by an evacuation guide lamp having a green light emitting area and a white light emitting area.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Transparent substrate 2 ... Anode 3 ... Hole transport layer 4 ... Light emission layer 5 ... Electron transport layer 6 ... Cathode 7 ... Light emission area | region (light emission site | part)
8 ... Non-light emitting area (non-light emitting part)
9. Green light emitting area 10. White light emitting area

Claims (18)

An evacuation guide lamp comprising an organic electroluminescence element in which an anode, a light emitting layer, and a cathode are laminated in this order, and a means for displaying a predetermined shape,
An evacuation guide lamp, wherein the light emitting layer is made of an organic material containing 50% by weight or more of a polymer compound and emits phosphorescence.   The escape guide lamp according to claim 1, wherein the means for displaying the predetermined shape is a plurality of the organic electroluminescent elements arranged in the same shape as the predetermined shape.   The escape guide lamp according to claim 1, wherein the means for displaying the predetermined shape is the anode and / or the cathode formed in the same shape as the predetermined shape.   The evacuation guide light according to claim 1, wherein the means for displaying the predetermined shape is the light emitting layer formed in the same shape as the predetermined shape.   The escape guide lamp according to any one of claims 1 to 4, wherein the polymer compound is a phosphorescent polymer compound.   The evacuation guide lamp according to any one of claims 1 to 5, wherein the organic material contains only a phosphorescent polymer compound. The evacuation guidance according to any one of claims 1 to 6, wherein the phosphorescent polymer compound has a polystyrene-reduced weight average molecular weight of 10 ⁵ or more as measured by GPC (gel permeation chromatography). light.   The evacuation guide lamp according to any one of claims 1 to 7, wherein the phosphorescent polymer compound is produced by radical polymerization of a phosphorescent compound and a charge transporting compound. The escape guide lamp according to claim 8, wherein at least a part of the phosphorescent compound is a phosphorescent iridium complex represented by the following formula (1):

[In Formula (1), R < ¹ > -R < ⁸ > is respectively independently a hydrogen atom, a halogen atom, a cyano group, a C1-C10 alkyl group, a C6-C10 aryl group, and C1-C10. Represents an atom or substituent selected from the group consisting of an amino group optionally substituted by an alkyl group, an alkoxy group having 1 to 10 carbon atoms, and a silyl group, and may be bonded to each other to form a condensed ring. .
L is one ligand selected from the ligands represented by the following formulas (2) to (4).

(In the formula (2), R ¹¹ ~R ¹⁸ are each independently a hydrogen atom, a halogen atom, a cyano group, an alkyl group having 1 to 10 carbon atoms, an aryl group having 6 to 10 carbon atoms, 1 to 10 carbon atoms Represents an atom or substituent selected from the group consisting of an amino group optionally substituted by an alkyl group, an alkoxy group having 1 to 10 carbon atoms, and a silyl group, and may be bonded to each other to form a condensed ring. ,
At least one of R ^{11 to} R ¹⁸ represents a substituent having a polymerizable functional group. ),

(In the formula (3), R ²¹ ~R ²³ independently represents a hydrogen atom, a cyano group, an alkyl group having 1 to 10 carbon atoms, an aryl group having 6 to 10 carbon atoms, alkyl group having 1 to 10 carbon atoms Represents an atom or a substituent selected from the group consisting of an amino group optionally substituted by, an alkoxy group having 1 to 10 carbon atoms, and a silyl group, and may be bonded to each other to form a condensed ring;
At least one of R ^{21 to} R ²³ represents a substituent having a polymerizable functional group. ),

(In the formula (4), R ^{31 to} R ³⁴ are each independently a hydrogen atom, a halogen atom, a cyano group, an alkyl group having 1 to 10 carbon atoms, an aryl group having 6 to 10 carbon atoms, or 1 to 10 carbon atoms. Represents an atom or substituent selected from the group consisting of an amino group optionally substituted by an alkyl group, an alkoxy group having 1 to 10 carbon atoms, and a silyl group, and may be bonded to each other to form a condensed ring. ,
At least one of R ^{31 to} R ³⁴ represents a substituent having a polymerizable functional group. ]].   The light emission external quantum efficiency of the said organic electroluminescent element is 5.0% or more, The escape guide light in any one of Claims 1-9 characterized by the above-mentioned. The evacuation according to any one of claims 1 to 10, wherein the front luminance of the light emitting region of the predetermined shape is 1000 cd / m ² or more when a current of 5 mA / cm ² is passed through the predetermined shape. Guide light. When the evacuation guide lamp is energized so that the front luminance of the light emitting area of the predetermined shape is 1000 cd / m ^2, and the light is emitted in the atmosphere of 100 ° C. while maintaining the current value at this time, the front luminance The evacuation guide light according to any one of claims 1 to 11, wherein the time until the value decreases to 500 cd / m ² is 100 hours or more.   The evacuation guide light according to any one of claims 1 to 12, wherein a light emission color of the light emitting layer is an arbitrary single color.   The evacuation guide lamp according to any one of claims 1 to 13, wherein the predetermined shape includes a green light emitting area and a light emitting area of another color.   The evacuation guide lamp according to any one of claims 1 to 14, wherein the organic electroluminescent element is formed on a plastic substrate or a plastic film substrate.   The evacuation guide light according to any one of claims 1 to 15, wherein the predetermined shape is controlled to repeat lighting and non-lighting at a constant time interval.   The escape guide lamp according to any one of claims 1 to 16, wherein the predetermined shape is displayed on both the anode side and the cathode side of the escape guide lamp.   The evacuation guide light according to claim 1, wherein the predetermined shape is a moving image.

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