WO2016163215A1

WO2016163215A1 - Organic electroluminescent element

Info

Publication number: WO2016163215A1
Application number: PCT/JP2016/058274
Authority: WO
Inventors: 井　宏元
Original assignee: コニカミノルタ株式会社
Priority date: 2015-04-09
Filing date: 2016-03-16
Publication date: 2016-10-13
Also published as: JPWO2016163215A1

Abstract

This organic electroluminescent element is configured by forming a light scattering layer, smoothing layer, first electrode, light emitting unit, and second electrode on a gas barrier film that has a metal-containing layer containing a compound consisting of at least one kind of metal selected from the group consisting of V, Nb, Ta, Ti, Zr, Hf, Mg, Y, and Al, and a gas barrier layer configured from a silicon-containing layer containing silicon and nitrogen.

Description

Organic electroluminescence device

The present invention relates to an organic electroluminescence element provided on a gas barrier film.

Organic electroluminescence devices using organic electroluminescence (hereinafter also simply referred to as EL) are thin-film, completely solid-state devices that can emit light at a low voltage of several volts to several tens of volts. It has many excellent features such as high luminous efficiency, thinness and light weight. For this reason, organic EL using a gas barrier film having a gas barrier layer on a thin and light resin substrate in recent years, particularly as backlights for various displays, display boards such as signboards and emergency lights, and surface light emitters such as illumination light sources. Devices are drawing attention.

As a gas barrier film used in such an organic EL device, for example, a method for producing a gas barrier film in which a gas barrier layer is formed by applying energy to a precursor layer formed by applying a solution on a substrate is also examined. Has been. In particular, studies using a polysilazane compound as a precursor of a gas barrier layer barrier layer have been widely conducted, and studies are being conducted as a technique for achieving both high productivity and barrier properties by coating. In particular, a gas barrier layer obtained by modifying a polysilazane compound using excimer light having a wavelength of 172 nm has been attracting attention.

As the gas barrier layer in which the polysilazane compound is modified, a molded body having a layer in which hydrocarbon compound ions are implanted in a layer containing the polysilazane compound has been proposed (for example, see Patent Document 1).
In addition, after applying a solution containing polysilazane and a catalyst on a substrate, removing the solvent to form a polysilazane layer, VUV radiation containing a wavelength component of less than 230 nm and a wavelength of 230 to 300 nm in an atmosphere containing water vapor A method has been proposed in which a polysilazane layer is modified by irradiating UV radiation containing components to form a gas barrier layer on a substrate (see, for example, Patent Document 2).
Furthermore, a polysilazane-modified film is formed multiple times by repeating the process of applying polysilazane on a resin substrate to form a polymer film having a film thickness of 250 nm or less and the process of irradiating the polymer film with vacuum ultraviolet light. A method for producing a flexible gas barrier film has been proposed (see, for example, Patent Document 3).

International Publication No. 2011-122547 Special table 2009-503157 JP 2009-255040 A

However, the organic EL device using the gas barrier film described above has good storage stability at a low temperature up to about 40 ° C., but has high storage stability in a very severe environment of high temperature and high humidity such as 80 ° C. and 85% RH. It will decline. For this reason, when the above-mentioned gas barrier film is used, the reliability of the organic EL element cannot be ensured.

In order to solve the above-described problems, the present invention provides a highly reliable organic electroluminescence device using a gas barrier film having excellent reliability.

The organic electroluminescence device of the present invention includes a gas barrier film having a gas barrier layer formed on a resin substrate, a light scattering layer provided on the gas barrier film, and a smoothing provided on the light scattering layer. An internal light extraction layer comprising layers, a first electrode and a second electrode provided on the internal light extraction layer, and a light emitting unit sandwiched between the first electrode and the second electrode. And then. The gas barrier layer includes a metal-containing layer containing a compound of at least one metal selected from V, Nb, Ta, Ti, Zr, Hf, Mg, Y, and Al, and a silicon-containing layer containing silicon and nitrogen And have.

According to the present invention, a highly reliable organic electroluminescence element can be provided.

It is a figure which shows schematic structure of an organic EL element.

<Organic electroluminescence device>
Hereinafter, specific embodiments of the organic electroluminescence element (organic EL element) will be described. FIG. 1 shows a schematic configuration diagram (cross-sectional view) of an organic EL element.

[Configuration of organic EL element]
The organic EL element 10 shown in FIG. 1 includes a gas barrier film 20 and an internal light extraction layer that is provided on the gas barrier film 20 and includes a light scattering layer 14 and a smoothing layer 11. Furthermore, on the smoothing layer 11, the 1st electrode 12, the light emission unit 13, and the 2nd electrode 15 are laminated | stacked in this order.

An extraction electrode 16 is provided at the end of the first electrode 12. The first electrode 12 and an external power source (not shown) are electrically connected via the extraction electrode 16. For the purpose of reducing the resistance of the first electrode 12, the auxiliary electrode 18 may be provided in contact with the first electrode 12.

Further, the layer structure of the light emitting unit 13 is not limited and may be a general layer structure. Here, an example in which the first electrode 12 functions as an anode (that is, an anode) and the second electrode 15 functions as a cathode (that is, a cathode) will be described. In this case, for example, the light-emitting unit 13 has a configuration in which a hole injection layer 13a / a hole transport layer 13b / a light-emitting layer 13c / an electron transport layer 13d / an electron injection layer 13e are stacked in this order from the first electrode 12 side that is an anode. Is exemplified. In addition, when the 1st electrode 12 functions as a cathode (namely, cathode) and the 2nd electrode 15 functions as an anode (namely, anode), the lamination | stacking order of the light emission unit 13 becomes said reverse.

It is essential that the light-emitting unit 13 having the above-described configuration has at least a light-emitting layer 13c formed using an organic material. The hole injection layer 13a and the hole transport layer 13b may be provided as a hole transport injection layer. The electron transport layer 13d and the electron injection layer 13e may be provided as an electron transport injection layer. Of these light emitting units 13, for example, the electron injection layer 13e may be made of an inorganic material.

Further, in addition to these layers, the light-emitting unit 13 may have a hole blocking layer, an electron blocking layer, or the like stacked as necessary. Furthermore, the light emitting layer 13c may have a structure in which each color light emitting layer that generates light emitted in each wavelength region is laminated, and each of these color light emitting layers is laminated via a non-light emitting intermediate layer. The intermediate layer may function as a hole blocking layer and an electron blocking layer. Furthermore, the second electrode 15 as the cathode may also have a laminated structure as necessary. In such a configuration, only a portion where the light emitting unit 13 is sandwiched between the first electrode 12 and the second electrode 15 becomes a light emitting region in the organic EL element 10.

The gas barrier film 20 includes a resin base material 21 and a gas barrier layer 22 provided on the resin base material 21. The gas barrier layer 22 includes a silicon-containing layer 23 provided on the resin base material 21 and a metal-containing layer 24 provided on the silicon-containing layer 23.

The silicon-containing layer 23 is formed of a silicon compound containing silicon and nitrogen. The metal-containing layer 24 is formed including a metal compound containing at least one metal M selected from V, Nb, Ta, Ti, Zr, Hf, Mg, Y, and Al.

Further, at the interface between the silicon-containing layer 23 and the metal-containing layer 24 of the gas barrier layer 22, when the silicon atom composition ratio is set to 100 in the atomic composition distribution profile obtained when XPS composition analysis is performed in the layer thickness direction. Preferably, there is a region A in which the nitrogen atom composition ratio exceeds 0 and is 60 or less and the metal atom composition ratio is 20 or more and 300 or less. The silicon-containing layer 23 and the metal-containing layer 24 are preferably in contact via the region A.
Further, the region A preferably has a region having an oxygen atom composition ratio of 40 or more and 300 or less when the silicon atom composition ratio is 100.

The organic EL element 10 is configured to extract the generated light (emitted light h) at least from the gas barrier film 20 side. The organic EL element 10 having such a configuration is sealed on a gas barrier film 20 with a sealing member 17 described later for the purpose of preventing deterioration of the light emitting unit 13 configured using an organic material or the like. Yes. The sealing member 17 is fixed to the gas barrier film 20 side through an adhesive layer 19. However, the terminal portions of the first electrode 12 (extraction electrode 16) and the second electrode 15 are provided in a state of being exposed from the sealing member 17 on the gas barrier film 20 while maintaining insulation from each other by the light emitting unit 13. It has been.

Hereinafter, details of each main layer for constituting the organic EL element 10 described above and a manufacturing method thereof will be described.

[Gas barrier film]
The gas barrier film 20 includes a resin base material 21 and a gas barrier layer 22 provided on the resin base material 21. The gas barrier layer 22 includes a metal-containing layer 24 containing at least one compound of metal M selected from V, Nb, Ta, Ti, Zr, Hf, Mg, Y, and Al, and silicon and nitrogen. A silicon-containing layer 23.

In the gas barrier film 20, even if the metal-containing layer 24 and the silicon-containing layer 23 are in the order of the metal-containing layer 24 and the silicon-containing layer 23 from the resin substrate 21 side, the silicon-containing layer 23 and the metal-containing layer 24 are in this order. It may be. In addition to the form in which the metal-containing layer 24 and the silicon-containing layer 23 are formed on one surface of the resin substrate 21, the metal-containing layer 24 and the silicon-containing layer 23 may be formed on both surfaces of the substrate. . Furthermore, another layer may be disposed between the resin base material 21 and each layer or on each layer.

(Atomic composition profile)
The gas barrier layer 22 has a composition SiM _x N _{y in the} vicinity of the interface between the metal-containing layer 24 and the silicon-containing layer 23 in the atomic composition distribution profile obtained when XPS composition analysis in the thickness direction is performed. ) And formula (2). The gas barrier film 20 having the gas barrier layer 22 having such a configuration is excellent in durability in a high temperature and high humidity environment.

In addition, it is preferable that the gas barrier layer 22 is formed of a coating solution in which the silicon-containing layer 23 contains polysilazane, and the region A satisfies the following formula (3).

It is necessary for the region A to satisfy the expressions (1) and (2) at the same time. That is, the region A is a region where silicon atoms and metal atoms are present at the same time, and the gas barrier film 20 has a high gas barrier property when the ratio of metal atom / silicon atom is 0.2 or more and 3.0 or less. Is expressed. In particular, the ratio of metal atom / silicon atom is preferably 0.5 or more and 2.0 or less.

Further, from the viewpoint of obtaining high gas barrier properties, it is preferable that the region A has a region having an oxygen atom composition ratio of 40 or more and 300 or less when the silicon atom composition ratio is 100. In particular, the oxygen atom composition ratio is preferably 100 or more and 200 or less.

Further, the gas barrier layer 22 has a particularly high gas barrier property when the silicon-containing compound used for forming the silicon-containing layer 23 contains polysilazane. In particular, in the case of containing this polysilazane, a region in which silicon atoms, metal atoms, and nitrogen atoms exist simultaneously is formed, the ratio of metal atoms / silicon atoms is 0.2 or more and 3.0 or less, and nitrogen atoms When the ratio of / silicon atom is 0.05 or more and 0.6 or less, extremely high gas barrier properties can be obtained.

When the ratio of nitrogen atom / silicon atom is less than 0.05, the content ratio of polysilazane contained in the silicon-containing layer 23 is low, or the polysilazane is modified to reduce silicon-nitrogen bonds. It is thought to decline. Also, when the ratio of nitrogen atom / silicon atom exceeds 0.6, the amount of silicon atom and metal atom are relatively decreased and the silicon-metal bond is also decreased by the increase of nitrogen atom. It is considered that the gas barrier property is lowered.

When the silicon-nitrogen bond (Si-N bond) of polysilazane is in contact with a metal atom formed by a method such as a vapor phase film-forming method, energy such as vacuum ultraviolet light is applied in contact with the metal atom. Therefore, it is considered that the silicon-metal bond is easily changed. For this reason, it is considered that a significantly higher gas barrier property can be obtained than when other silicon-containing compounds having no silicon-nitrogen bond are used.

The thickness of region A is an integral multiple of 2.5 nm because a depth profile is obtained every 2.5 nm in the depth direction in terms of SiO ₂ in the XPS composition analysis shown below. Moreover, when the area | region A has several types of metal M, x is calculated from the sum total which weighted content of each metal.

The control of the composition and thickness of such a region A is compared between the formation of the metal-containing layer 24 (or silicon-containing layer 23) and the formation of the silicon-containing layer 23 (or metal-containing layer 24). It can be carried out by a method such as storing the film under conditions of low temperature and humidity, or storing it in a dry nitrogen atmosphere.

Furthermore, from the viewpoint that higher gas barrier properties can be obtained, when the atomic composition of the region A is represented by SiM _x N _y O _z , the region A has the region B represented by the following formula (4). Is preferred.

The above equation (4) means that the total number of bonds of O and N is less than the total number of bonds of Si and M. Although it is estimated, when (4 + ax) − (3y + 2z) in the above formula (4) exceeds 0, it is considered that a direct bond between Si and M is formed. It is considered that as the value of (4 + ax) − (3y + 2z) increases, the ratio of direct bonding between Si and M increases, the density of the composition in region A increases, and the gas barrier properties are further improved. Therefore, (4 + ax) − (3y + 2z) in the region B is more preferably 1 or more, further preferably 2 or more, and particularly preferably 3 or more. In addition, when the area | region B has multiple types of metal M, x is calculated from the sum total which weighted content of each metal.

Control of the value of (4 + ax) − (3y + 2z) is, for example, in the case where the formation of the layer containing the metal M is performed by sputtering, for example, a metal as a target or a metal in which oxygen is lost stoichiometrically This can be done by using an oxide and appropriately adjusting the amount of oxygen introduced during sputtering.

The position where the region B is formed is not particularly limited, but is preferably in the vicinity of the interface between the region A and the metal-containing layer 24 or in the vicinity of the interface between the region A and the silicon-containing layer 23. If the region B is formed in the vicinity of these interfaces, it means that a co-oxynitride layer of Si and metal M is formed at the interface between the metal-containing layer 24 and the silicon-containing layer 23. This is because the co-oxynitride layer of Si and M is considered to exhibit high wet heat resistance.

The composition of the region A and the region B can be measured by the following method.
By XPS composition analysis, a composition distribution profile in the thickness direction is measured in the vicinity of the interface between the metal-containing layer 24 and the silicon-containing layer 23, and the composition is indicated by SiM _x N _y O _z At this time, it is determined whether or not the region A is present from the relationship between x and y. If the area A is included, the value of (4 + ax) − (3y + 2z) is obtained to determine whether or not the area B is further included.

(XPS composition analysis conditions)
・ Equipment: ULVAC-PHI QUANTERASXM
・ X-ray source: Monochromatic Al-Kα
・ Sputtering ion: Ar (2 keV)
Depth profile: After sputtering equivalent to 2.5 nm in terms of SiO ₂ , measurement is repeated to obtain a depth profile for every 2.5 nm in the SiO ₂ equivalent depth direction.
Quantification: The background is obtained by the Shirley method, and quantified using the relative sensitivity coefficient method from the obtained peak area. Data processing uses MultiPak manufactured by ULVAC-PHI.

Although the reason why the gas barrier layer 22 having the above-described structure exhibits a durability effect in a high-temperature and high-humidity environment is unclear, the following mechanism is conceivable. In addition, the following mechanism is speculative and is not limited to the following mechanism.

The gas barrier layer 22 is presumed to exhibit gas barrier properties by forming a high-density region A in which silicon atoms and metal atoms are present simultaneously and silicon atoms and metal atoms are directly bonded. Even if the ratio of metal atom / silicon atom is less than 0.2 or more than 3.0, the bond between the silicon atom and the metal atom is reduced, so that the barrier property is considered to be lowered.

The silicon-containing layer 23 obtained by applying a coating liquid containing a silicon-containing compound and drying exhibits gas barrier properties by having a specific composition. In addition, in the silicon-containing layer 23 formed by this manufacturing method, unlike the case where it is formed by the vapor phase film forming method, foreign substances such as particles are hardly mixed at the time of film formation, and a gas barrier layer with very few defects can be formed. It becomes possible.

The silicon-containing layer 23 containing silicon and nitrogen exhibits gas barrier properties by having a specific composition. However, the silicon-containing layer 23 is not completely stable against oxidation, and may be gradually oxidized in a high-temperature and high-humidity environment, resulting in a decrease in gas barrier properties.

On the other hand, the gas barrier film 20 has a metal-containing layer 24 together with the silicon-containing layer 23, and has the region A in the vicinity of the interface between the silicon-containing layer 23 and the metal-containing layer 24. Since the metal-containing layer 24 is more easily oxidized than the silicon-containing layer 23, the metal-containing layer 24 is oxidized first and the oxidation of the silicon-containing layer 23 is suppressed. For this reason, it is thought that the gas barrier film 20 is excellent in durability in a high temperature and high humidity environment. That is, it is considered that the gas barrier film 20 has the region A, whereby the durability under a high temperature and high humidity environment is particularly improved.

[Resin substrate]
Specific examples of the resin substrate 21 include polyester resin, methacrylic resin, methacrylic acid-maleic acid copolymer, polystyrene resin, transparent fluororesin, polyimide, fluorinated polyimide resin, polyamide resin, polyamideimide resin, and polyether. Imide resin, cellulose acylate resin, polyurethane resin, polyether ether ketone resin, polycarbonate resin, alicyclic polyolefin resin, polyarylate resin, polyether sulfone resin, polysulfone resin, cycloolefin copolymer, fluorene ring modified polycarbonate resin, fat Examples thereof include base materials containing a thermoplastic resin such as a ring-modified polycarbonate resin, a fluorene ring-modified polyester resin, and an acryloyl compound. The resin base material 21 can be used individually or in combination of 2 or more types.

The resin substrate 21 is preferably made of a material having heat resistance. Specifically, a material having a linear expansion coefficient of 15 ppm / K or more and 100 ppm / K or less and a glass transition temperature (Tg) of 100 ° C. or more and 300 ° C. or less is used. The Tg and linear expansion coefficient of the resin base material 21 can be adjusted by an additive or the like.

When producing the organic EL element 10 using the gas barrier film 20, the gas barrier film 20 may be exposed to a process of 150 ° C. or higher. In this case, when the linear expansion coefficient of the base material in the gas barrier film 20 exceeds 100 ppm / K, the substrate dimensions are not stabilized in the above-described thermal process, and the barrier performance is deteriorated with thermal expansion and contraction. Or it is easy to produce the malfunction that it cannot endure a heat process. If the linear expansion coefficient of the resin base material 21 is less than 15 ppm / K, it may break like the gas barrier film 20 glass and the flexibility may deteriorate.

More preferable specific examples of the thermoplastic resin that can be used as the resin substrate 21 include, for example, polyethylene terephthalate (PET: 70 ° C.), polyethylene naphthalate (PEN: 120 ° C.), polycarbonate (PC: 140 ° C.), and fat. Cyclic polyolefin (for example, ZEONOR (registered trademark) 1600: 160 ° C. manufactured by Nippon Zeon Co., Ltd.), polyarylate (PAr: 210 ° C.), polyether sulfone (PES: 220 ° C.), polysulfone (PSF: 190 ° C.), cyclo Olefin copolymer (COC: Compound described in JP-A No. 2001-150584: 162 ° C.), polyimide (for example, Neoprim (registered trademark): 260 ° C. manufactured by Mitsubishi Gas Chemical Co., Inc.), fluorene ring-modified polycarbonate (BCF-PC: JP 2000-22760 No. 225 ° C.), cycloaliphatic modified polycarbonate (IP-PC: JP 2000-227603 JP-A compound: 205 ° C.), acryloyl compound (JP-A 2002-80616) : 300 ° C. or higher), etc. (in parentheses indicate Tg).

In the case of a configuration (bottom emission) in which emitted light of the organic EL element 10 is extracted from the gas barrier film 20 side, a transparent resin base material 21 is used. That is, the resin substrate 21 having a light transmittance of usually 80% or more, preferably 85% or more, more preferably 90% or more is used. The light transmittance is calculated by measuring the total light transmittance and the amount of scattered light using an integrating sphere light transmittance measuring device described in JIS K7105: 1981, and subtracting the diffuse transmittance from the total light transmittance. Apply.

However, in the case of a configuration (top emission) in which the light emitted from the organic EL element 10 is extracted from the side opposite to the gas barrier film 20, transparency is not necessarily required. In such a case, an opaque material can be used as the resin base material 21. Examples of the opaque material include polyimide, polyacrylonitrile, and known liquid crystal polymers.

Further, the resin base material 21 may be an unstretched film or a stretched film. The resin base material 21 can be manufactured by a conventionally known general method. Regarding the production method of these base materials, the matters described in paragraphs [0051] to [0055] of International Publication No. 2013/002026 can be appropriately employed.

The surface of the resin base material 21 may be subjected to various known treatments for improving adhesion, such as corona discharge treatment, flame treatment, oxidation treatment, or plasma treatment, and the above treatment as necessary. May be performed in combination.

The resin substrate 21 may be a single layer or a laminated structure of two or more layers. When the resin base material 21 has a laminated structure of two or more layers, the resin base materials 21 may be of the same type or different types. The thickness of the resin base material 21 (the total thickness in the case of a laminated structure of two or more layers) is preferably 10 to 200 μm, and more preferably 20 to 150 μm.

[Silicon-containing layer]
The silicon-containing layer 23 is formed using a silicon-containing compound containing silicon and nitrogen. The silicon-containing layer 23 is obtained by applying and drying a coating solution containing a silicon-containing compound (silicon-containing coating solution). The silicon-containing layer 23 may be a single layer or a laminated structure of two or more layers.

Examples of the silicon-containing compound include polysiloxane, polysilsesquioxane, polysilazane, polysiloxazan, polysilane, polycarbosilane, and the like. Among these, it is preferable to have at least one selected from the group consisting of a silicon-nitrogen bond, a silicon-hydrogen bond, and a silicon-silicon bond.

More preferably, the silicon-containing compound is a polysilazane having a silicon-nitrogen bond and a silicon-hydrogen bond, a polysiloxazan having a silicon-nitrogen bond, a polysiloxane having a silicon-hydrogen bond, and a polysilsesqui having a silicon-hydrogen bond. Oxane, polysilane having a silicon-silicon bond can be used. When the silicon-containing layer 23 is formed using a silicon-containing compound having any one of a silicon-nitrogen bond, a silicon-hydrogen bond, and a silicon-silicon bond, the above-described region B is easily formed.

Specific examples of polysiloxane, polysilsesquioxane, and polysiloxazan include compounds described in paragraphs [0093] to [0121] of JP2012-116101A. As the polysiloxane, hydrogenated (hydrogen) polysiloxane is particularly preferable.

The form of polysilane is not particularly limited, and may be a non-cyclic polysilane (linear polysilane, branched polysilane, network polysilane, etc.), a homopolymer such as cyclic polysilane, a random copolymer, It may be a copolymer such as a block copolymer, an alternating copolymer, or a comb copolymer.

When the polysilane is an acyclic polysilane, the terminal group (terminal substituent) of the polysilane may be a hydrogen atom, a halogen atom (such as a chlorine atom), an alkyl group, a hydroxyl group, an alkoxy group, or a silyl group. May be.

Specific examples of polysilanes include polydialkylsilanes such as polydimethylsilane, poly (methylpropylsilane), poly (methylbutylsilane), poly (methylpentylsilane), poly (dibutylsilane), poly (dihexylsilane), poly Copolymers of polydiarylsilanes such as (diphenylsilane), homopolymers such as poly (alkylarylsilane) such as poly (methylphenylsilane), dialkylsilanes such as dimethylsilane-methylhexylsilane copolymer and other dialkylsilanes Polymers, arylsilane-alkylarylsilane copolymers such as phenylsilane-methylphenylsilane copolymer, dimethylsilane-methylphenylsilane copolymer, dimethylsilane-phenylhexylsilane copolymer, dimethylsilane-methylnaphthylsila Copolymer, methyl propyl silane - include copolymers such as alkyl aryl silane copolymer - dialkyl silane and methyl phenyl silane copolymer.

Polycarbosilane is a polymer compound having a (—Si—C—) bond in the main chain in the molecule. As polycarbosilane, what contains the repeating unit represented by following formula (d) is preferable.

In the formula, Rw and Rv each independently represent a hydrogen atom, a hydroxyl group, an alkyl group, an aryl group, an alkenyl group, or a monovalent heterocyclic group. A plurality of Rw and Rv may be the same or different. R represents an alkylene group, an arylene group or a divalent heterocyclic group.
The weight average molecular weight of the polycarbosilane having a repeating unit represented by the formula (d) is usually from 400 to 12,000.

The heterocyclic ring of the monovalent heterocyclic group of Rw and Rv is not particularly limited as long as it is a 3- to 10-membered cyclic compound containing at least one hetero atom such as an oxygen atom, a nitrogen atom, or a sulfur atom in addition to a carbon atom. There is no. Specific examples of the monovalent heterocyclic group include 2-pyridyl group, 3-pyridyl group, 4-pyridyl group, 2-thienyl group, 3-thienyl group, 2-furyl group, 3-furyl group, and 3-pyrazolyl. Group, 4-pyrazolyl group, 2-imidazolyl group, 4-imidazolyl group, 1,2,4-triazin-3-yl group, 1,2,4-triazin-5-yl group, 2-pyrimidyl group, 4- Pyrimidyl group, 5-pyrimidyl group, 3-pyridyl group, 4-pyridazyl group, 2-pyrazyl group, 2- (13,5-triazyl) group, 3- (1,2,4-triazyl) group, 6- ( 1,2,4-triazyl) group, 2-thiazolyl group, 5-thiazolyl group, 3-isothiazolyl group, 5-isothiazolyl group, 2- (13,4-thiadiazolyl) group, 3- (1,2,4- Thiadiazolyl) group, 2-oxazolyl group 4-oxazolyl group, 3-isoxazolyl group, 5-isoxazolyl group, 2- (13,4-oxadiazolyl) group, 3- (1,2,4-oxadiazolyl) group, 5- (1,2,3-oxadiazolyl) Groups and the like. These groups may have a substituent such as an alkyl group, an aryl group, an alkoxy group, or an aryloxy group at an arbitrary position.

Examples of the alkylene group of R include alkylene groups having 1 to 10 carbon atoms such as a methylene group, an ethylene group, a propylene group, a trimethylene group, a tetramethylene group, a pentamethylene group, a hexamethylene group, and an octamethylene group. Examples of the arylene group include arylene groups having 6 to 20 carbon atoms such as a p-phenylene group, a 1,4-naphthylene group, and a 2,5-naphthylene group. The alkylene group and arylene group of R may have a substituent such as an alkyl group, an aryl group, an alkoxy group, or a halogen atom at an arbitrary position.

The divalent heterocyclic group for R may be a divalent group derived from a 3- to 10-membered heterocyclic compound containing at least one hetero atom such as an oxygen atom, a nitrogen atom, or a sulfur atom in addition to a carbon atom. There are no particular restrictions. Specific examples of the divalent heterocyclic group include thiophene diyl groups such as 2,5-thiophenediyl group, frangyl groups such as 2,5-furandiyl group, and selenophene such as 2,5-selenophenediyl group. Diyl group, pyrrole diyl group such as 2,5-pyrrole diyl group, 2,5-pyridinediyl group, pyridinediyl group such as 2,6-pyridinediyl group, 2,5-thieno [3,2-b] thiophenediyl group Thienothiophene diyl group such as 2,5-thieno [2,3-b] thiophenediyl group, Quinoline diyl group such as 2,6-quinolinediyl group, 1,4-isoquinolinediyl group, 1,5-isoquinolinediyl group, etc. Isoquinolinediyl group, quinoxalinediyl group such as 5,8-quinoxalinediyl group, and benzo [4,7-benzo [1,2,5] thiadiazolediyl group , 2,5] thiadiazole diyl group, benzothiazole diyl group such as 4,7-benzothiazole diyl group, carbazole diyl group such as 2,7-carbazole diyl group, 3,6-carbazole diyl group, 3,7-phenoxy Phenoxazinediyl group such as sazinediyl group, phenothiazinediyl group such as 3,7-phenothiazinediyl group, dibenzosiloldiyl group such as 2,7-dibenzosiloldiyl group, 2,6-benzo [1,2-b: 4,5-b ′] dithiophenediyl group, 2,6-benzo [1,2-b: 5,4-b ′] dithiophenediyl group, 2,6-benzo [2,1-b: 3, Benzodithiophene diyl groups such as 4-b ′] dithiophene diyl group and 2,6-benzo [1,2-b: 3,4-b ′] dithiophene diyl group. The divalent heterocyclic group for R may have a substituent such as an alkyl group, an aryl group, an alkoxy group, or a halogen atom at an arbitrary position.

Among these, in formula (d), Rw and Rv are each independently a hydrogen atom, an alkyl group or an aryl group, and polycarbosilane containing a repeating unit in which R is an alkylene group or an arylene group is more preferable. Furthermore, polycarbosilane containing a repeating unit in which Rw and Rv are each independently a hydrogen atom or an alkyl group and R is an alkylene group is preferable.

As a material for forming the silicon-containing layer 23, polysilazane is more preferable.
Polysilazane is a polymer having a silicon-nitrogen bond, such as SiO ₂ , Si ₃ N ₄ having a bond such as Si—N, Si—H, or N—H, and ceramics such as both intermediate solid solutions SiO _x N _y. It is a precursor inorganic polymer. Specifically, polysilazane preferably has a structure represented by the following general formula (I).

In the general formula (I), R ₁ , R ₂ and R ₃ are each independently a hydrogen atom, a substituted or unsubstituted alkyl group, aryl group, vinyl group or (trialkoxysilyl) alkyl group. . At this time, R ₁ , R ₂ and R ₃ may be the same or different. In the general formula (I), n is an integer, and is preferably determined so that the polysilazane having the structure represented by the general formula (I) has a number average molecular weight of 150 to 150,000 g / mol. .
In the compound having the structure represented by the general formula (I), one of preferred embodiments is perhydropolysilazane in which all of R ₁ , R ₂ and R ₃ are hydrogen atoms.

The polysilazane preferably has a structure represented by the following general formula (II).

In the general formula (II), R _{1 ′} , R _{2 ′} , R _{3 ′} , R _{4 ′} , R _{5 ′} and R _{6 ′} each independently represent a hydrogen atom, a substituted or unsubstituted alkyl group, An aryl group, a vinyl group or a (trialkoxysilyl) alkyl group. In this case, R _{1 ′} , R _{2 ′} , R _{3 ′} , R _{4 ′} , R _{5 ′} and R _{6 ′} may be the same or different. In the general formula (II), n ′ and p are integers, and the polysilazane having the structure represented by the general formula (II) is determined to have a number average molecular weight of 150 to 150,000 g / mol. Is preferred. Note that n ′ and p may be the same or different.

Of the polysilazanes of the above general formula (II), R _{1 ′} , R _{3 ′} and R _{6 ′} each represent a hydrogen atom, R _{2 ′} , R _{4 ′} and R _{5 ′} each represent a methyl group, R _{1 ',} R _3' and R _{6 'are} each a hydrogen atom, R _{_2',} R ₄ _'are each a methyl group, R _5' compound represents a vinyl group, _{_{or, R 1 ', R 3'}} , A compound in which R _{4 ′} and R _{6 ′} each represent a hydrogen atom and R _{2 ′} and R _{5 ′} each represent a methyl group is preferred.

Alternatively, the polysilazane preferably has a structure represented by the following general formula (III).

In the general formula (III), R _{1 ″} , R _{2 ″} , R _{3 ″} , R _{4 ″} , R _{5 ″} , R _{6 ″} , R _{7 ″} , R _{8 ″} and R _{9 ″} are each independently A hydrogen atom, a substituted or unsubstituted alkyl group, aryl group, vinyl group or (trialkoxysilyl) alkyl group, wherein R _{1 ″} , R _{2 ″} , R _{3 ″} , R _{4 ″} , R _{5 ″} , R _{6 ″} , R _{7 ″} , R _{8 ″} and R _{9 ″} may be the same or different.

In the general formula (III), n ″, p ″ and q are integers, and the polysilazane having the structure represented by the general formula (III) has a number average molecular weight of 150 to 150,000 g / mol. Preferably, it is defined. Note that n ″, p ″, and q may be the same or different.

Among the polysilazanes of the above general formula (III), R _{1 ″} , R _{3 ″} and R _{6 ″} each represent a hydrogen atom, and R _{2 ″} , R _{4 ″} , R _{5 ″} and R _{8 ″} each represent a methyl group. , R _{9 ″} represents a (triethoxysilyl) propyl group, and R _{7 ″} represents an alkyl group or a hydrogen atom.

On the other hand, the organopolysilazane in which a part of the hydrogen atom portion bonded to Si is substituted with an alkyl group or the like has improved adhesion to the base material as a base by having an alkyl group such as a methyl group and is hard. And toughness can be imparted to the ceramic film made of brittle polysilazane. For this reason, even when the film thickness (average) of the silicon-containing layer 23 is increased, there is an advantage that generation of cracks can be suppressed. For this reason, these perhydropolysilazane and organopolysilazane may be appropriately selected according to the application, and may be used in combination.

Perhydropolysilazane is presumed to have a linear structure and a ring structure centered on 6- and 8-membered rings. Its molecular weight is approximately 600 to 2000 (polystyrene conversion) in terms of number average molecular weight (Mn), and there are liquid or solid substances, and the state varies depending on the molecular weight.

Polysilazane is commercially available in a solution in an organic solvent, and a commercially available product can be used as it is as a silicon-containing coating solution for forming the silicon-containing layer 23. Examples of commercially available polysilazane solutions include NN120, NN120-20, NAX120-20, NN110, NN310, NN320, NL110A, NL120A, NL120-20, NL150A, NP110, NP140, and SP140 manufactured by AZ Electronic Materials Co., Ltd. It is done. These polysilazane solutions can be used alone or in combination of two or more.

As another example of polysilazane used for forming the silicon-containing layer 23, the following polysilazane can be mentioned. For example, a silicon alkoxide-added polysilazane obtained by reacting silicon alkoxide with the above polysilazane (Japanese Patent Laid-Open No. 5-238827), a glycidol-added polysilazane obtained by reacting glycidol (Japanese Patent Laid-Open No. 6-122852), and an alcohol Alcohol-added polysilazane (JP-A-6-240208) obtained by reaction, metal carboxylate-added polysilazane (JP-A-6-299118) obtained by reacting a metal carboxylate, and an acetylacetonate complex containing a metal Acetylacetonate complex-added polysilazane (JP-A-6-306329) obtained by reacting with metal, and metal-silica-added polysilazane (JP-A-7-196986) obtained by adding metal fine particles, etc. Policy Than, and the like.

When polysilazane is used to form the silicon-containing layer 23, the polysilazane content in the silicon-containing layer 23 before irradiation with vacuum ultraviolet rays is 100% by mass when the total mass of the silicon-containing layer 23 is 100% by mass. Can do. Moreover, when the silicon-containing layer 23 before vacuum ultraviolet irradiation contains things other than polysilazane, it is preferable that the content rate of the polysilazane in a layer is 10 to 99 mass%, and is 40 to 95 mass%. More preferably, it is 70 mass% or less and 95 mass% or less.

(Silicon-containing coating solution)
The solvent for preparing the coating liquid (silicon-containing coating liquid) for forming the silicon-containing layer 23 is not particularly limited as long as it can dissolve the silicon-containing compound. As the solvent, an organic solvent which does not contain water and reactive groups (for example, hydroxyl group or amine group) that easily react with the silicon-containing compound and is inert to the silicon-containing compound is preferable. Protic organic solvents are more preferred. Specifically, the solvent includes an aprotic solvent, for example, an aliphatic hydrocarbon such as pentane, hexane, cyclohexane, toluene, xylene, solvesso, and terpene, and a hydrocarbon such as alicyclic hydrocarbon and aromatic hydrocarbon. Solvents, halogen hydrocarbon solvents such as methylene chloride and trichloroethane, esters such as ethyl acetate and butyl acetate, ketones such as acetone and methyl ethyl ketone, aliphatic ethers such as dibutyl ether, dioxane and tetrahydrofuran, ethers such as alicyclic ethers Examples include tetrahydrofuran, dibutyl ether, mono- and polyalkylene glycol dialkyl ethers (diglymes), and the like. The solvent is selected according to purposes such as the solubility of polysilazane and the evaporation rate of the solvent, and may be used alone or in the form of a mixture of two or more.

The concentration of the silicon-containing compound in the silicon-containing coating solution is not particularly limited. The concentration of the silicon-containing compound in the silicon-containing coating solution varies depending on the thickness of the layer and the pot life of the coating solution, but is preferably 1 to 80% by mass, more preferably 5 to 50% by mass, and still more preferably 10 to 40% by mass. %.

When the silicon-containing layer 23 is modified, it is preferable that the silicon-containing coating solution contains a catalyst for promoting the modification. As the catalyst for promoting the reforming, a basic catalyst is preferable, and in particular, N, N-diethylethanolamine, N, N-dimethylethanolamine, triethanolamine, triethylamine, 3-morpholinopropylamine, N, N , N ′, N′-tetramethyl-13-diaminopropane, amine catalysts such as N, N, N ′, N′-tetramethyl-1,6-diaminohexane, Pt compounds such as Pt acetylacetonate, propionic acid Examples thereof include Pd compounds such as Pd, metal catalysts such as Rh compounds such as Rh acetylacetonate, and N-heterocyclic compounds. Of these, it is preferable to use an amine catalyst. The concentration of the catalyst added at this time is preferably in the range of 0.1 to 10% by mass, more preferably 0.5 to 7% by mass, based on the silicon compound. By setting the amount of catalyst to be in this range, it is possible to avoid excessive silanol formation due to rapid progress of the reaction, reduction in film density, increase in film defects, and the like.

In the silicon-containing coating solution, the following additives can be used as necessary. For example, cellulose ethers, cellulose esters such as ethyl cellulose, nitrocellulose, cellulose acetate, cellulose acetobutyrate, natural resin, rubber, rosin resin, synthetic resin, polymerization resin, condensation resin, aminoplast, urea resin Melamine formaldehyde resin, alkyd resin, acrylic resin, polyester resin, modified polyester resin, epoxy resin, polyisocyanate, blocked polyisocyanate, polysiloxane and the like.

(Application method)
As a method for applying the silicon-containing coating solution, a conventionally known appropriate wet coating method is employed. Specific examples include spin coating method, roll coating method, flow coating method, ink jet method, spray coating method, printing method, dip coating method, casting film forming method, bar coating method, die coating method, gravure printing method and the like. It is done.
The coating thickness is appropriately set according to the preferred thickness and purpose.

After applying the coating solution, the coating film is dried. By drying the coating film, the organic solvent contained in the coating film is removed. At this time, all of the organic solvent contained in the coating film may be dried or may be partially left. Even when a part of the organic solvent is left, a suitable silicon-containing layer 23 can be obtained. The remaining solvent is removed later.

The drying temperature of the coating film varies depending on the substrate to be applied, but is preferably 50 to 200 ° C. For example, when a polyethylene terephthalate film having a glass transition temperature (Tg) of 70 ° C. is used as the resin base material 21, the drying temperature is set to 150 ° C. or lower in consideration of deformation of the resin base material 21 due to heat. Is preferred. The temperature is set by using a hot plate, oven, furnace or the like. The drying time is preferably set to a short time. For example, when the drying temperature is 150 ° C., the drying time is preferably set within 30 minutes. The drying atmosphere may be any condition such as an air atmosphere, a nitrogen atmosphere, an argon atmosphere, a vacuum atmosphere, or a reduced pressure atmosphere with a controlled oxygen concentration.

The coating film obtained by applying the silicon-containing coating solution may include a step of removing moisture before irradiation with vacuum ultraviolet rays or during irradiation with vacuum ultraviolet rays. As a method for removing moisture, a form in which the coating film is retained and dehumidified in a low humidity environment is preferable. Since humidity in a low-humidity environment varies with temperature, the relationship between temperature and humidity shows a preferred form by defining the dew point temperature. A preferable dew point temperature is 4 ° C. or lower (temperature 25 ° C./humidity 25%), and a more preferable dew point temperature is −5 ° C. or lower (temperature 25 ° C./humidity 10%). It is preferable to appropriately set the time for holding and maintaining the coating film. Specifically, it is preferable that the dew point temperature is −5 ° C. or lower and the maintaining time is 1 minute or longer. The lower limit of the dew point temperature is not particularly limited, but is usually −50 ° C. or higher, and preferably −40 ° C. or higher. This is a preferable form from the viewpoint of promoting the dehydration reaction of the silicon-containing layer 23 converted to silanol by removing water before or during the modification treatment.

(Vacuum UV irradiation)
The coating film containing the silicon-containing compound formed as described above can be used as it is as the silicon-containing layer 23, but the obtained coating film is irradiated with vacuum ultraviolet rays to form silicon oxynitride or the like. It is preferable to form the silicon-containing layer 23 by carrying out a conversion reaction. In order from the resin base material 21 side, the gas barrier layer 22 having the silicon-containing layer 23 and the metal-containing layer 24 is subjected to vacuum ultraviolet irradiation to perform from the formation of the silicon-containing layer 23 to the formation of the metal-containing layer 24. It is difficult for gas barrier properties to deteriorate due to environmental effects. In the gas barrier layer 22 having the metal-containing layer 24 and the silicon-containing layer 23 in order from the resin base material 21 side, the vacuum barrier irradiation improves the gas barrier property, so that the vacuum ultraviolet irradiation is preferably performed. .

Vacuum ultraviolet irradiation can be adapted to both batch processing and continuous processing, and can be appropriately selected depending on the shape of the resin substrate 21 to be used. For example, in the case of batch processing, it can be processed in an ultraviolet baking furnace equipped with an ultraviolet ray generation source. The ultraviolet baking furnace itself is generally known. For example, an ultraviolet baking furnace manufactured by I-Graphics Co., Ltd. can be used. Moreover, when a target is a long film form, an ultraviolet-ray can be continuously irradiated in the drying zone which equipped the ultraviolet-ray generation source, conveying this. The time required for ultraviolet irradiation is generally 0.1 seconds to 10 minutes, preferably 0.5 seconds to 3 minutes, although it depends on the substrate used and the composition and concentration of the silicon-containing layer 23.

The modification by vacuum ultraviolet irradiation uses light energy of 100 to 200 nm which is larger than the interatomic bonding force in the silicon-containing compound (especially polysilazane compound). Preferably, light energy having a wavelength of 100 to 180 nm is used. By this vacuum ultraviolet irradiation, an oxidative reaction with active oxygen or ozone is advanced while the atoms are directly cut by the action of only photons called photon processes. Thus, a film containing silicon oxynitride can be formed at a relatively low temperature (about 200 ° C. or less). In addition, when performing the following excimer irradiation processing, it is preferable to use heat processing together with excimer irradiation processing.

The vacuum ultraviolet ray source may be any source that generates light having a wavelength of 100 to 180 nm. Preferably, an excimer radiator (eg, an Xe excimer lamp) having a maximum emission at about 172 nm, a low pressure mercury vapor lamp having an emission line at about 185 nm, a medium and high pressure mercury vapor lamp having a wavelength component of 230 nm or less, and about Excimer lamp with maximum emission at 222 nm.

Among these, the Xe excimer lamp emits ultraviolet light having a short wavelength of 172 nm at a single wavelength, and thus has excellent luminous efficiency. Since this light has a large oxygen absorption coefficient, it can generate radical oxygen atom species and ozone at a high concentration with a very small amount of oxygen. Moreover, it is known that the energy of light having a short wavelength of 172 nm has a high ability to dissociate organic bonds. The coating film can be modified in a short time by the high energy of the active oxygen, ozone and ultraviolet radiation.

¡Excimer lamps have high light generation efficiency and can be lit with low power. Further, light having a long wavelength that causes a temperature increase due to light is not emitted, and energy is irradiated at a short wavelength in the ultraviolet region, so that an increase in the surface temperature of the irradiation object can be suppressed. For this reason, it is suitable for flexible film materials such as PET that are easily affected by heat.

Oxygen is required for the reaction by irradiation with vacuum ultraviolet rays, but since vacuum ultraviolet rays are absorbed by oxygen, the efficiency of the ultraviolet irradiation process is likely to be reduced by oxygen. For this reason, it is preferable to perform the irradiation with vacuum ultraviolet rays in a state where the oxygen concentration and the water vapor concentration are as low as possible. That is, the oxygen concentration at the time of vacuum ultraviolet irradiation is preferably 10 to 20000 volume ppm (0.001 to 2 volume%), and preferably 50 to 10000 volume ppm (0.005 to 1 volume%). More preferred. Further, the water vapor concentration at the time of irradiation with vacuum ultraviolet rays is preferably in the range of 1000 to 4000 ppm by volume.

The gas satisfying the irradiation atmosphere used for the vacuum ultraviolet irradiation is preferably a dry inert gas, and particularly preferably a dry nitrogen gas from the viewpoint of cost. The oxygen concentration can be adjusted by measuring the flow rates of oxygen gas and inert gas introduced into the irradiation chamber and changing the flow rate ratio.

In the vacuum ultraviolet ray irradiation step, the illuminance of the vacuum ultraviolet ray on the coating surface received by the coating film is preferably 1 mW / cm ² to 10 W / cm ² , more preferably 30 mW / cm ² to 200 mW / cm ^2. and further preferably ^{50mW / cm 2 ~ 160mW / cm} 2. If it is 1 mW / cm ² or more, the reforming efficiency is improved. If it is 10 W / cm < ² > or less, the ablation which may arise in a coating film and the damage to the resin base material 21 can be reduced.

When the silicon-containing layer 23 and the metal-containing layer 24 are formed in this order from the resin base material 21 side, the irradiation energy amount (irradiation amount) of vacuum ultraviolet rays on the surface of the coating film is 0.1 to 10 J / cm ^2. Is preferably 0.1 to 7 J / cm ² , and more preferably 0.1 to 3 J / cm ² . When the metal-containing layer 24 and the silicon-containing layer 23 are formed in this order from the resin base material 21 side, the irradiation energy amount (irradiation amount) of vacuum ultraviolet rays onto the surface of the coating film is 1 to 10 J / cm ^2. Preferably, it is 3-7 J / cm ² . If it is this range, generation | occurrence | production of the crack by excessive modification | reformation and the thermal deformation of the resin base material 21 can be suppressed, and productivity will improve.

The vacuum ultraviolet rays used for irradiating the surface of the coating film may be generated from plasma formed by a gas containing at least one of CO, CO ₂ and CH ₄ . Further, as the gas containing at least one of CO, CO ₂ and CH ₄ (hereinafter also referred to as carbon-containing gas), the carbon-containing gas may be used alone, but the rare gas or H ₂ is used as the main gas. It is preferable to add a small amount of the contained gas. Examples of plasma generation methods include capacitively coupled plasma.

[Metal-containing layer]
The gas barrier film 20 includes a silicon-containing layer 23 and a metal-containing layer 24 containing a compound of at least one metal M selected from V, Nb, Ta, Ti, Zr, Hf, Mg, Y, and Al. Have. The metal-containing layer 24 containing the metal M is more easily oxidized than the silicon-containing layer 23, and suppresses oxidation of the silicon-containing layer 23. The metal-containing layer 24 is preferably formed by a vapor deposition method using a metal compound containing the metal M.

The standard redox potential of major metals is shown in Table 1 below.

The metal compound containing the metal M is not particularly limited, and examples thereof include an oxide, nitride, carbide, oxynitride, or oxycarbide of the metal M. In particular, from the viewpoint of more effectively suppressing oxidation of the silicon-containing layer 23, an oxide of metal M is preferable. The metal compound may be used alone or in combination of two or more.

Further, the metal M contained in the metal compound is preferably a metal having a lower redox potential than silicon. By using a layer containing a metal compound having a lower oxidation-reduction potential than silicon, better barrier properties can be obtained. Specific examples of the metal having a lower redox potential than silicon include V, Nb, Ta, Zr, Ti, Hf, and Y, for example. These metals may be used alone or in combination of two or more. Among these, V, Nb, and Ta, which are Group 5 elements, are particularly effective in suppressing the oxidation of the silicon-containing layer 23. For this reason, the metal-containing layer 24 preferably contains at least one metal compound selected from V, Nb, and Ta as the metal M. Furthermore, it is preferable that the metal containing layer 24 contains Nb from which the compound with favorable transparency is obtained as the metal M from a viewpoint of optical characteristics.

The content of the metal compound in the metal-containing layer 24 is preferably 50% by mass or more, more preferably 80% by mass or more, and 95% by mass or more with respect to the total mass of the metal-containing layer 24. More preferably, it is particularly preferably 98% by mass or more, and most preferably 100% by mass (that is, the metal-containing layer 24 is made of a metal compound).

(Formation of metal-containing layer)
For the formation of the metal-containing layer 24, it is preferable to use a vapor deposition method from the viewpoint of easy adjustment of the composition ratio between the metal element and oxygen. The vapor deposition method is not particularly limited, and examples thereof include physical vapor deposition (PVD) methods such as sputtering, vapor deposition, and ion plating, plasma CVD (chemical vapor deposition), and ALD (Atomic Layer). Chemical vapor deposition methods such as Deposition). Among them, it is preferable to use a sputtering method because film formation can be performed without damaging the lower layer and high productivity is obtained.

For the film formation by sputtering, bipolar sputtering, magnetron sputtering, dual magnetron (DMS) sputtering using an intermediate frequency region, ion beam sputtering, ECR sputtering, or the like can be used alone or in combination of two or more. The target application method is appropriately selected according to the target type, and either DC (direct current) sputtering or RF (high frequency) sputtering may be used. A reactive sputtering method using a transition mode that is intermediate between the metal mode and the oxide mode can also be used. The reactive sputtering method is preferable because the metal oxide film can be formed at a high film formation speed by controlling the sputtering phenomenon so as to be in the transition region. When DC sputtering or DMS sputtering is performed, a metal oxide thin film can be formed by using a metal for the target and introducing oxygen into the process gas. In the case of forming a film by RF (high frequency) sputtering, a metal oxide target can be used. As the inert gas used for the process gas, He, Ne, Ar, Kr, Xe, or the like can be used, and Ar is preferably used. Furthermore, by introducing oxygen, nitrogen, carbon dioxide, and carbon monoxide into the process gas, a thin film of a metal compound such as a metal oxide, nitride, nitride oxide, or carbonate can be produced. Examples of film formation conditions in the sputtering method include applied power, discharge current, discharge voltage, time, and the like, which can be appropriately selected according to the sputtering apparatus, film material, film thickness, and the like. Preferably, a sputtering method using a metal oxide as a target is particularly used because it has a higher film formation rate and higher productivity.

The metal-containing layer 24 may be a single layer or a laminated structure of two or more layers. When the metal-containing layer 24 has a laminated structure of two or more layers, the metal compounds contained in the metal-containing layer 24 may be the same or different.

Since the metal-containing layer 24 is considered to be a layer having a function of suppressing the oxidation of the silicon-containing layer 23 and maintaining the gas barrier property, the gas barrier property is not necessarily required. Accordingly, the metal-containing layer 24 can be effective even in a relatively thin layer. Specifically, in the case of the layer configuration of the resin base material 21 / the silicon-containing layer 23 / the metal-containing layer 24, the thickness of the metal-containing layer 24 (the total thickness in the case of a laminated structure of two or more layers) is the barrier From the viewpoint of in-plane uniformity of the property, the thickness is preferably 1 to 200 nm, more preferably 2 to 100 nm, and further preferably 3 to 50 nm. In particular, when the thickness is 50 nm or less, the productivity of the metal-containing layer 24 is further improved. Further, in the case of the layer structure of the resin base material 21 / the metal-containing layer 24 / the silicon-containing layer 23, the thickness of the metal-containing layer 24 (the total thickness in the case of a laminated structure of two or more layers) is a barrier property. From the viewpoint of in-plane uniformity, the thickness is preferably 1 to 200 nm, more preferably 2 to 150 nm, and even more preferably 10 to 150 nm.

[Method of forming gas barrier film]
When the gas barrier film 20 has a structure of resin base material 21 / silicon-containing layer 23 / metal-containing layer 24, it is preferable to form the silicon-containing layer 23 and then form the metal-containing layer 24. When the region A is formed, the silicon-containing layer 23 may be modified by vacuum ultraviolet irradiation or not. If the region A is formed, good gas barrier properties can be obtained without performing the vacuum ultraviolet irradiation of the silicon-containing layer 23. For this reason, by not performing the vacuum ultraviolet irradiation, high-speed film formation is possible, and high productivity can be obtained. On the other hand, from the viewpoint of more efficiently form regions A, it is preferred to perform the modification with the vacuum ultraviolet ray irradiation of the silicon-containing layer 23 at an irradiation energy amount of less than 3J / cm ^2, and less than 1 J / cm ² It is more preferable. Furthermore, an aspect in which the irradiation energy amount is 0 J / cm ² , that is, the modification is not performed by vacuum ultraviolet irradiation can be preferably selected.

When forming the silicon-containing layer 23, when the vacuum ultraviolet irradiation is not performed, the silicon-containing layer 23 is a coating film obtained by applying and drying a coating solution containing a silicon-containing compound at 5 to 40 ° C. It is formed by storing for 1 to 1000 hours under conditions of a relative humidity of 0 to 60% RH. Thereafter, the metal-containing layer 24 is preferably formed.

By storing in the above-described environment, it is possible to suppress undesirable changes in the surface composition of the silicon-containing layer 23 from the time when the silicon-containing layer 23 is applied and dried until the metal-containing layer 24 is formed. The gas barrier performance under high temperature and high humidity conditions is improved. For example, when polysilazane is used as the silicon-containing compound, the undesirable change is a decrease in the nitrogen content on the surface of the silicon-containing layer 23 and an increase in the oxygen content due to the reaction between moisture in the atmosphere and polysilazane. Etc.

In the case of the structure of resin base material 21 / silicon-containing layer 23 / metal-containing layer 24, the film thickness per layer of the silicon-containing layer 23 (the total thickness in the case of a laminated structure of two or more layers) is the gas barrier performance. From this point of view, the thickness is preferably 10 to 1000 nm, more preferably 50 to 600 nm, and still more preferably 50 to 300 nm. If it is this range, the balance of gas barrier property and durability becomes favorable and is preferable.

When the gas barrier film 20 has a structure of resin base material 21 / metal-containing layer 24 / silicon-containing layer 23, after forming the metal-containing layer 24, a coating solution containing a silicon-containing compound is applied and dried. Once formed, the coating is modified by vacuum UV treatment.

The effect of suppressing the oxidation of the silicon-containing layer 23 by the metal-containing layer 24 is higher when the silicon-containing layer 23 is modified. For this reason, when it is the structure of the resin base material 21 / metal containing layer 24 / silicon containing layer 23, it is preferable that the silicon containing layer 23 is modified to the lower surface side close to the metal containing layer 24.

Therefore, when the silicon-containing layer 23 is modified by irradiating vacuum ultraviolet light of 172 nm from the upper surface side, the thickness of the silicon-containing layer 23 is relatively thin in order to allow 172 nm light to reach the lower surface of the silicon-containing layer 23. It is preferable. Specifically, the film thickness per layer of the silicon-containing layer 23 (the total thickness in the case of a laminated structure of two or more layers) is preferably 300 nm or less, more preferably 200 nm or less, The thickness is more preferably 150 nm or less, and particularly preferably 100 nm or less. On the other hand, if the silicon-containing layer 23 is too thin, the gas barrier properties deteriorate. For this reason, considering the gas barrier properties of the silicon-containing layer 23, the thickness is preferably 5 nm or more, more preferably 10 nm or more, further preferably 20 nm or more, and particularly preferably 40 nm or more. preferable.

In the case of the structure of the resin base material 21 / the metal-containing layer 24 / the silicon-containing layer 23, the region A can be formed as follows. For example, after the metal-containing layer 24 is formed, it is stored for 1 to 1000 hours under the conditions of 5 to 40 ° C. and relative humidity 0 to 60% RH where the formed metal-containing layer 24 is formed. Thereafter, by forming the silicon-containing layer 23 on the metal-containing layer 24, the gas barrier layer 22 having the region A can be produced.

(Layers with various functions)
In addition to the above configuration, the gas barrier film 20 can be provided with layers having various functions.

(Anchor coat layer)
For the purpose of improving the adhesion between the resin substrate 21 and the metal-containing layer 24 or the silicon-containing layer 23, the anchor coat layer is formed on the surface of the resin substrate 21 on the side on which the metal-containing layer 24 and the silicon-containing layer 23 are formed. May be formed. The thickness of the anchor coat layer is not particularly limited, but is preferably about 0.5 to 10 μm.

As anchor coating agents used in the anchor coat layer, polyester resins, isocyanate resins, urethane resins, acrylic resins, ethylene vinyl alcohol resins, vinyl modified resins, epoxy resins, modified styrene resins, modified silicone resins, alkyl titanates, etc. are used alone. Or it can use in combination of 2 or more types.

Conventionally known additives can be added to these anchor coating agents. The anchor coating agent is coated on the support by a known method such as roll coating, gravure coating, knife coating, dip coating, spray coating, etc., and the anchor coating is applied by drying and removing the solvent, diluent, etc. Can be formed. The application amount of the anchor coating agent is preferably about 0.1 to 5.0 g / m ² (dry state).

Also, the anchor coat layer can be formed by a vapor phase method such as physical vapor deposition or chemical vapor deposition. For example, as described in JP-A-2008-142941, an inorganic film mainly composed of silicon oxide can be formed for the purpose of improving the adhesive layer 19 property and the like. Alternatively, as described in Japanese Patent Application Laid-Open No. 2004-314626, when an inorganic thin film is formed on the anchor coat layer by a vapor phase method, the gas generated from the substrate side is blocked to some extent, and the composition of the inorganic thin film is changed. An anchor coat layer can also be formed for control.

(Hard coat layer)
The resin base material 21 may have a hard coat layer on the surface (one side or both sides). Examples of the material contained in the hard coat layer include a thermosetting resin and an active energy ray curable resin, but an active energy ray curable resin is preferable because it is easy to mold. Such curable resins can be used singly or in combination of two or more.

The active energy ray-curable resin is a resin that is cured through a crosslinking reaction or the like by irradiation with active energy rays such as ultraviolet rays or electron beams. As the active energy ray curable resin, a material containing a monomer having an ethylenically unsaturated double bond is preferably used. This material is cured by irradiating active energy rays such as ultraviolet rays and electron beams to form a layer containing a cured product of the active energy ray curable resin, that is, a hard coat layer. Typical examples of the active energy ray curable resin include an ultraviolet curable resin and an electron beam curable resin, and an ultraviolet curable resin that is cured by irradiation with ultraviolet rays is preferable. Moreover, you may use the commercially available resin base material 21 in which the hard-coat layer is formed previously.

(Smoothing layer)
The gas barrier film 20 may have a smoothing layer between the resin base material 21 and the metal-containing layer 24 or the silicon-containing layer 23. The smoothing layer is flattened to flatten the rough surface of the resin substrate 21 where protrusions and the like are present, or to fill the unevenness and pinholes generated in the transparent inorganic compound layer by the protrusions existing on the resin substrate 21 To be provided. Such a smoothing layer is basically produced by curing a photosensitive material or a thermosetting material.

Examples of the photosensitive material for the smoothing layer include a resin composition containing an acrylate compound having a radical reactive unsaturated compound, a resin composition containing an acrylate compound and a mercapto compound having a thiol group, epoxy acrylate, urethane acrylate, and polyester. Examples thereof include a resin composition in which a polyfunctional acrylate monomer such as acrylate, polyether acrylate, polyethylene glycol acrylate, or glycerol methacrylate is dissolved. Specifically, a UV curable organic / inorganic hybrid hard coat material manufactured by JSR Corporation may be mentioned.

Further, as the photosensitive material for the smoothing layer, OPSTAR (registered trademark) series can be used. It is also possible to use an arbitrary mixture of the above resin compositions, and any photosensitive resin containing a reactive monomer having one or more photopolymerizable unsaturated bonds in the molecule can be used. There are no particular restrictions.

Specific examples of thermosetting materials include TutProm Series (Organic Polysilazane) manufactured by Clariant, SP COAT heat-resistant clear paint manufactured by Ceramic Coat, Nanohybrid Silicone manufactured by Adeka, Unico manufactured by DIC, Inc. Dick (registered trademark) V-8000 series, EPICLON (registered trademark) EXA-4710 (ultra-high heat resistant epoxy resin), various silicon resins manufactured by Shin-Etsu Chemical Co., Ltd., inorganic and organic nanocomposite materials manufactured by Nittobo Co., Ltd. Examples thereof include SSG coat, thermosetting urethane resin composed of acrylic polyol and isocyanate prepolymer, phenol resin, urea melamine resin, epoxy resin, unsaturated polyester resin, and silicon resin. Among these, an epoxy resin-based material having heat resistance is particularly preferable.

The method for forming the smoothing layer is not particularly limited, but is preferably formed by a wet coating method such as a spin coating method, a spray method, a blade coating method, or a dip method, or a dry coating method such as an evaporation method.

In the formation of the smoothing layer, additives such as an antioxidant, an ultraviolet absorber, and a plasticizer can be added to the above-described photosensitive resin as necessary. Further, regardless of the position where the smoothing layer is laminated, in any smoothing layer, an appropriate resin or additive may be used for improving the film forming property and preventing the generation of pinholes in the film.

The thickness of the smoothing layer is preferably in the range of 1 to 10 μm, more preferably in the range of 2 to 7 μm from the viewpoint of improving the heat resistance of the film and facilitating the balance adjustment of the optical properties of the film. It is preferable.
The smoothness of the smoothing layer is a value expressed by the surface roughness defined by JIS B 0601: 2001, and the ten-point average roughness Rz is preferably 10 nm or more and 30 nm or less.

[Internal light extraction layer]
In the organic EL element 10, the internal light extraction layer includes a light scattering layer 14 and at least one smoothing layer 11. The light scattering layer 14 preferably contains light scattering particles having an average particle diameter of 0.2 μm or more and less than 1 μm and a binder. The smoothing layer 11 is mainly composed of silicon oxide, niobium oxide, silicon nitride, or niobium nitride. The water vapor permeability is preferably less than 0.1 g / (m ² · 24 h). In particular, the smoothing layer 11 may contain a reaction product of an inorganic silicon compound or an organic silicon compound, or niobium oxide as a main component in order to effectively prevent moisture from entering and lead to a long life of the organic EL element. preferable.

From the viewpoint of long-term storage stability, it is preferable that the water vapor transmission rate Wg of the gas barrier layer 22, the water vapor transmission rate Ws of the light scattering layer 14, and the water vapor transmission rate Wf of the smoothing layer 11 satisfy the following conditional expression.
Wg ≦ Wf <Ws

Although it is preferable that the absolute value of the water vapor transmission rate Ws of the light scattering layer 14 is low, in principle the gas permeability of the light scattering layer 14 is large and the water vapor transmission rate Ws of the light scattering layer 14 is also large. On the other hand, it is possible in principle to improve the performance by making Wf the lowest, but a change in the amount of gas adsorbed on the light scattering layer 14 causes a decrease in the light emission efficiency of the device and a deterioration in the film strength. There is. For this reason, in the organic EL element 10, it is preferable to design the water vapor permeability Wg of the gas barrier layer 22 to be the lowest. In order to lower the water vapor transmission rate Wg of the gas barrier layer 22, a gas barrier layer is provided on the opposite surface (light emission surface side) of the resin base material 21, and basic constituent members of the resin base material 21 / gas barrier layer 22 are provided. Two or more can be used in layers.

In addition, from the viewpoint of blocking moisture from entering the light-emitting unit 13 and gas from various materials, the layer mainly composed of oxide or nitride of silicon or niobium constituting the smoothing layer 11 is formed by a dry process. It is preferable to form a film.
From the viewpoint of improving the smoothness of the smoothing layer 11, it is preferable that the surface side (first electrode 12) of the smoothing layer 11 is formed by a wet process.

From the viewpoint of suppressing the light extraction efficiency inhibition by the smoothing layer 11, the refractive index of the smoothing layer 11 is preferably in the range of 1.7 to 3.0. As a means for adjusting the refractive index of the smoothing layer 11, it is preferable that nanoparticles having a refractive index in the range of 1.7 to 3.0 are contained in the smoothing layer.

In order to prevent moisture from entering the light emitting unit 13, shut off gas from various materials, and improve the smoothness of the smoothing layer 11, the smoothing layer 11 includes a plurality of layers. It is preferable to become. When the smoothing layer 11 is formed of a plurality of layers, each layer may be formed by the same process or may be formed by different processes. Further, they may be formed of the same material or different materials.

Examples of such combinations include, for example, lamination by a wet process, lamination by a dry process, lamination of a layer formed by a dry process on a layer formed by a wet process, and formation by a wet process on a layer formed by a dry process. For example, the deposited layers can be stacked. Preferably, the layer on the first electrode 12 side is formed by a dry process, and the layer on the light scattering layer 14 side is formed by a wet process. Specifically, in order to make the unevenness of the surface of the light scattering layer 14 more flat, the smoothing layer 11 is a layer mainly composed of an oxide or nitride of silicon or niobium in order from the resin base material 21 side. It is preferable to have a structure having a layer formed by a wet process.

The smoothing layer 11 preferably contains a reaction product of niobium oxide, an inorganic silicon compound, or an organic silicon compound as a main component in order to effectively prevent moisture from entering and lead to a long life of the organic EL element. From the viewpoint of luminous efficiency, the smoothing layer 11 preferably has a refractive index in the range of 1.7 to 3.0. In the case where the smoothing layer 11 is composed of a plurality of layers, it is preferable that the folding ratio of each layer is in the range of 1.7 to 3.0. From the viewpoint of achieving both of these characteristics, the smoothing layer 11 is particularly preferably composed mainly of niobium oxide, silicon nitride, or silicon oxynitride.
Further, from the viewpoint of protecting the light scattering layer 14 with the minimum smoothing layer 11 and preventing intrusion of water vapor or the like in the atmosphere, the light scattering layer 14 is preferably patterned in the sealing region. .

[Smoothing layer]
The smoothing layer 11 is mainly composed of an oxide or nitride of silicon (Si) or niobium (Nb), or has a water vapor permeability of less than 0.1 g / (m ² · 24 h). And This effectively prevents transmission of gas emitted from the light scattering layer 14 and the smoothing layer 11, which will be described later, moisture in the atmosphere, and the like, and also causes high temperatures due to irregularities on the surface of the gas barrier layer 22 or the light scattering layer 14. -It is possible to prevent adverse effects such as deterioration of storage stability and electrical short circuit (short circuit) in a high humidity atmosphere. Here, the main component means a component having the highest constituent ratio among the components constituting the smoothing layer 11.

Here, the water vapor permeability of the smoothing layer 11 is a value measured by a method according to JIS K 7129-1992, and the water vapor permeability (25 ± 0.5 ° C., relative humidity 90 ± 2% RH). Is less than 0.1 g / (m ² · 24 h), preferably 0.01 g / (m ² · 24 h) or less, and more preferably 0.001 g / (m ² · 24 h) or less.

The refractive index of the smoothing layer 11 is preferably in the range of 1.7 to 3.0, more preferably in the range of 1.7 to 2.5, and particularly preferably 1.7 to 2. Within the range of 2. For the refractive index, a value at a wavelength of 633 nm measured at 25 ° C. with an ellipsometer is treated as a representative value.

When the smoothing layer 11 is made of a low refractive index material (refractive index less than 1.7), the layer thickness is preferably as thin as possible, and more preferably less than 100 nm. However, the smoothing layer 11 preferably has a certain gas barrier property, and the layer thickness at which a continuous film is formed is the lower limit. In this respect, 5 nm or more is necessary, 10 nm or more is preferable, and 30 nm or more is particularly preferable.

On the other hand, when the smoothing layer 11 is made of a high refractive index material (refractive index of 1.7 or more), the upper limit of the layer thickness is not particularly limited, and the lower limit of the layer thickness is made of the low refractive index material. It is the same. However, when the film of the smoothing layer 11 has visible light absorption, it is preferable that the layer thickness is as thin as possible, and an optimum layer thickness can be set in view of necessary gas barrier properties and extraction efficiency.

Further, the smoothing layer 11 preferably has a small absorption (a value obtained by dividing the total value of T% R% in the spectral wavelength measurement with an integrating sphere) in the entire visible light region of the layer having a thickness of 100 nm, preferably It is less than 10%, more preferably less than 5%, still more preferably less than 3%, most preferably less than 1%.

In addition, the smoothing layer 11 is important for bending resistance at a thickness of 100 nm. A gas barrier layer 22 is provided on a PET film, a smoothing layer 11 having a thickness of 100 nm is formed thereon, and the diameter at which cracks occur in 100 uneven bending tests is preferably less than 30 mmφ, and less than 15 mmφ It is more preferable that it is less than 10 mmφ.

Hereinafter, the method for forming the smoothing layer 11 will be described separately for a dry process and a wet process.

(Film formation by dry process)
Examples of the oxide or nitride of silicon or niobium contained in the smoothing layer 11 include, for example, a reaction product of an inorganic silicon compound, a reaction product of an organic silicon compound, niobium oxide, niobium oxynitride, niobium nitride, and carbonized oxide. Niobium, niobium nitride niobium, or the like can be given. Among these, as the oxide or nitride of silicon or niobium contained in the smoothing layer 11, silicon nitride, silicon oxynitride, or niobium oxide is preferable.

Examples of the reaction product of the inorganic silicon compound include silicon oxide, silicon oxynitride, silicon nitride, silicon oxide carbide, and silicon nitride carbide.
Examples of the organosilicon compound include hexamethyldisiloxane, 1,13,3-tetramethyldisiloxane, vinyltrimethylsilane, methyltrimethylsilane, hexamethyldisilane, methylsilane, dimethylsilane, trimethylsilane, diethylsilane, propylsilane, Examples include phenylsilane, vinyltriethoxysilane, vinyltrimethoxysilane, tetramethoxysilane, tetraethoxysilane, phenyltrimethoxysilane, methyltriethoxysilane, and octamethylcyclotetrasiloxane. Among these, hexamethyldisiloxane and 1,13,3-tetramethyldisiloxane are preferable from the viewpoint of handling during film formation and characteristics such as gas barrier properties of the resulting smoothing layer 11. Moreover, these organosilicon compounds can be used individually by 1 type or in combination of 2 or more types.

For example, when the smoothing layer 11 containing the reaction product of hexamethyldisiloxane is formed by plasma CVD, the reaction gas as a reaction gas with respect to the molar amount (flow rate) of hexamethyldisiloxane as a raw material gas is used. The molar amount (flow rate) of oxygen is preferably 12 times or less, more preferably 10 times or less the stoichiometric ratio. In addition, the lower limit of the molar amount (flow rate) of oxygen relative to the molar amount (flow rate) of hexamethyldisiloxane in the film forming gas should be greater than 0.1 times the molar amount (flow rate) of hexamethyldisiloxane. It is more preferable that the amount be more than 0.5 times.

By containing hexamethyldisiloxane and oxygen at such a ratio, carbon atoms and hydrogen atoms in hexamethyldisiloxane that have not been completely oxidized are taken into the smoothing layer 11, and a desired smoothing layer is obtained. 11 can be formed. And it becomes possible to exhibit the outstanding gas barrier property and bending resistance in the smoothing layer 11 obtained.

When the smoothing layer 11 made of niobium oxide is formed, for example, as a film forming apparatus, an RF magnetron plasma generation unit and a niobium oxide (Nb ₂ O ₅ ) target are provided, and these are vacuumed by the introduction unit. An apparatus connected to the processing chamber can be given. In this film forming apparatus, an RF magnetron sputtering source is constituted by an RF magnetron plasma generation unit and a target. A plasma of argon gas is generated by an RF magnetron plasma generation unit, and RF is applied to a disk-shaped target, so that niobium atoms and oxygen atoms of the target are sputtered (RF magnetron sputtering), and these are positioned downstream. The smoothing layer 11 can be formed by adhering to the surface.

Furthermore, as a method of forming the smoothing layer 11 made of niobium oxide, the method disclosed in Japanese Patent Application Laid-Open No. 2006-28624 can be cited. In this method, niobium metal is used as a target. In addition, when a niobium oxide thin film is formed on the substrate surface by sputtering, the amount of reactive gas introduced is adjusted by plasma emission monitoring (PEM). Thereby, the intensity of the plasma generated from the niobium metal of the target can be controlled. This method can produce a niobium oxide thin film having excellent film formation speed and good optical properties.

Examples of the dry process include a vapor deposition method (resistance heating, EB method, etc.), a plasma CVD method, a sputtering method, an ion plating method, etc., but a water vapor permeability is small and a dense film with low film stress is used. Any of them can be suitably used as long as they can be formed. In addition, in film formation using a dry process, it is rare that the component becomes a stoichiometric component due to the presence of a small amount of gas in addition to the introduced gas. Specifically, SiO ₂ is a stoichiometric representative value, but since an actual film has a width of about SiO _x (x = 1.9 to 2.1), SiO ₂ including these is included. Treat as. The above-mentioned atomic ratio can be determined by a conventionally known method, and can be measured by, for example, an analyzer using X-ray photoelectron spectroscopy (XPS).

(Deposition by wet process)
When forming the smoothing layer 11 using a wet process, it is preferable to contain the silicon dioxide compound which is a reaction product of an inorganic silicon compound. In particular, polysilazane is preferably used as the inorganic silicon compound, but is not particularly limited thereto, and a known material can be used. As polysilazane, polysilazane represented by the above general formula (I) can be used as in the case of the light scattering layer 14 described above. From the viewpoint of the denseness of the smoothing layer 11 to be obtained, it is preferable to use perhydropolysilazane (PHPS) in which all of R ₁ , R ₂ and R _{3 in} the general formula (I) are hydrogen atoms.

The smoothing layer 11 can be formed by applying a coating liquid containing polysilazane and drying it, followed by irradiation with vacuum ultraviolet rays. The concentration of polysilazane in the coating liquid containing polysilazane varies depending on the layer thickness of the smoothing layer 11 and the pot life of the coating liquid, but is preferably about 0.2 to 35% by mass.

As an organic solvent for preparing a coating liquid containing polysilazane, it is preferable to use a solvent that does not contain a lower alcohol or water that easily reacts with polysilazane. For example, hydrocarbon solvents such as aliphatic hydrocarbons, alicyclic hydrocarbons and aromatic hydrocarbons, halogenated hydrocarbon solvents, ethers such as aliphatic ethers and alicyclic ethers can be used. Specific examples include hydrocarbons such as pentane, hexane, cyclohexane, toluene, xylene, solvesso and turben, halogen hydrocarbons such as methylene chloride and trichloroethane, and ethers such as dibutyl ether, dioxane and tetrahydrofuran. These organic solvents may be selected according to purposes such as the solubility of polysilazane and the evaporation rate of the solvent, and a plurality of organic solvents may be mixed and used.

Further, in order to promote modification to silicon oxynitride, a coating solution containing polysilazane is added to an amine catalyst, a Pt compound such as Pt acetylacetonate, a Pd compound such as propionic acid Pd, or an Rh compound such as Rh acetylacetonate. A metal catalyst such as can also be added. In particular, it is preferable to use an amine catalyst. Specific amine catalysts include N, N-diethylethanolamine, N, N-dimethylethanolamine, triethanolamine, triethylamine, 3-morpholinopropylamine, N, N, N ′, N′-tetramethyl-13 -Diaminopropane, N, N, N ', N'-tetramethyl-1,6-diaminohexane and the like.

In the coating solution, the addition amount of the catalyst with respect to polysilazane is preferably in the range of 0.1 to 10% by mass, more preferably in the range of 0.2 to 5% by mass, and 0.5 to 2%. More preferably, it is in the range of mass%. By making the addition amount of the catalyst within this range, it is possible to avoid excessive silanol formation, a decrease in film density, an increase in film defects, and the like due to rapid progress of the reaction.

Any appropriate method can be adopted as a method of applying the coating liquid containing polysilazane. Specific examples include a roll coating method, a flow coating method, an ink jet method, a spray coating method, a printing method, a dip coating method, a cast film forming method, a bar coating method, and a gravure printing method.

The thickness of the coating is appropriately set according to the purpose. For example, the thickness of the coating film is preferably in the range of 50 nm to 2 μm, more preferably in the range of 70 nm to 1.5 μm, and still more preferably in the range of 100 nm to 1 μm.

(Excimer processing)
The smoothing layer 11 is modified to at least part of polysilazane into silicon oxynitride by irradiating the layer containing polysilazane with vacuum ultraviolet rays. As the vacuum ultraviolet light source, the above rare gas excimer lamp is preferably used.

In the smoothing layer 11, the illuminance of vacuum ultraviolet rays on the coating surface received by the coating containing polysilazane is preferably in the range of 30 to 200 mW / cm ² , and in the range of 50 to 160 mW / cm ^2. It is more preferable. If it is 30 mW / cm ² or more, there is no concern that the reforming efficiency is lowered, and if it is 200 mW / cm ² or less, the coating film is not ablated and the substrate is not damaged.

Irradiation energy amount of the VUV in the coated surface is preferably in the range of 200 ~ 10000mJ / cm ^2, and more preferably in a range of 500 ~ 5000mJ / cm ^2. At 200 mJ / cm ² or more, the modification can be sufficiently performed. Further, if it is 10000 mJ / cm ² or less, it is not excessively reformed, and there is no generation of cracks or thermal deformation of the substrate.

Oxygen is required for the reaction by irradiation with vacuum ultraviolet rays, but since vacuum ultraviolet rays are absorbed by oxygen, the efficiency of the ultraviolet irradiation process is likely to be reduced by oxygen. For this reason, it is preferable to perform the irradiation with vacuum ultraviolet rays in a state where the oxygen concentration and the water vapor concentration are as low as possible. That is, the oxygen concentration at the time of vacuum ultraviolet irradiation is preferably in the range of 10 to 10000 ppm, more preferably in the range of 50 to 5000 ppm, and still more preferably in the range of 1000 to 4500 ppm.

As the gas satisfying the irradiation atmosphere used at the time of vacuum ultraviolet irradiation, a dry inert gas is preferable, and a dry nitrogen gas is particularly preferable from the viewpoint of cost. The oxygen concentration can be adjusted by measuring the flow rates of oxygen gas and inert gas introduced into the irradiation chamber and changing the flow rate ratio.

(Nanoparticles)
The smoothing layer 11 is preferably formed by containing nanoparticles having a refractive index in the range of 1.7 to 3.0 in a binder as a medium. If the refractive index of the nanoparticles is 1.7 or more, the refractive index of the smoothing layer 11 can be easily adjusted. Moreover, if the refractive index of a nanoparticle is 3.0 or less, the multiple scattering in a layer will be suppressed and transparency will not be reduced.
Nanoparticles are defined as fine particles (colloidal particles) having a particle size dispersed in a dispersion medium of the order of nanometers. The particles include discrete particles (primary particles) and aggregated particles (secondary particles), which are defined as nanoparticles including secondary particles.

The lower limit of the particle diameter of the nanoparticles is usually preferably 5 nm or more, more preferably 10 nm or more, and further preferably 15 nm or more. Moreover, as an upper limit of the particle diameter of a nanoparticle, it is preferable that it is 70 nm or less, It is more preferable that it is 60 nm or less, It is further more preferable that it is 50 nm or less. When the particle diameter of the nanoparticles is in the range of 5 to 60 nm, it is preferable in that high transparency can be obtained. As long as the function as the smoothing layer 11 is not impaired, the particle size distribution of the nanoparticles is not limited and may be wide or narrow and may have a plurality of distributions.

The nanoparticle is more preferably TiO ₂ (titanium dioxide sol) from the viewpoint of stability. Among TiO ₂ , rutile type is more preferable than anatase type, since the catalytic activity is low and the weather resistance of the smoothing layer 11 and the adjacent layer becomes high and the refractive index is high. As a method for preparing the titanium dioxide sol, for example, JP-A-63-17221, JP-A-7-819, JP-A-9-165218, JP-A-11-43327 and the like can be referred to.

The smoothing layer 11 is formed by a wet process, a dry process, or the like, but these methods may be used in combination, or one method may be used in combination with the same composition or different compositions. In the case of a composite film or a laminated film, the function and action as the smoothing layer 11 are expressed as a whole. In addition, in the case of a wet process, it is only necessary that the film after drying, curing, and modification after coating is formed as the smoothing layer 11, and the smoothing layer 11 has a distribution of components in the depth direction from the surface. You may have a slope.

Also, since the above-mentioned viewpoints can be achieved together, silicon oxynitride, silicon nitride, and niobium oxide are particularly advantageous and preferable in the dry process. Regarding the coating material in the wet process, excimer curing under a low oxygen concentration of polysilazane is preferable because of its high refractive index. Furthermore, regarding the coating material, the refractive index can be adjusted in the addition / combination of nanoparticles, and adaptation in combination with such nanoparticles is very suitable.

Further, when the light emitting unit 13 is provided on the gas barrier layer 22 or the light scattering layer 14, the smoothing layer 11 is in a high temperature / high humidity atmosphere due to the unevenness of the surface of the gas barrier layer 22 or the light scattering layer 14. It is provided mainly for the purpose of preventing adverse effects such as deterioration of storage stability and electrical short circuit (short circuit), and is a layer provided between the light scattering layer 14 and the first electrode 12.

(Configuration of other smoothing layers)
It is important that the smoothing layer 11 has flatness in order to satisfactorily form the first electrode 12 thereon. The thickness of the smoothing layer 11 needs to be thick to some extent in order to reduce the surface roughness of the light scattering layer 14, but it needs to be thin enough not to cause energy loss due to absorption.

The surface property of the smoothing layer 11 is preferably such that the arithmetic average roughness Ra is in the range of 0.5 to 50 nm, more preferably 30 nm or less, particularly preferably 10 nm or less, and most preferably 5 nm or less. By setting the arithmetic average roughness Ra within the range of 0.5 to 50 nm, it is possible to suppress defects such as a short circuit of the organic EL element 10. As for the arithmetic average roughness Ra, 0 nm is preferable, but 0.5 nm is set as a lower limit value as a practical level limit value.

The arithmetic average roughness Ra of the surface represents the arithmetic average roughness according to JIS B 0601-2001. The surface roughness (arithmetic average roughness Ra) was measured by using an atomic force microscope (AFM) manufactured by Digital Instruments, and continuously measured with a detector having a stylus having a minimum tip radius. It is calculated from the cross-section curve, and is measured three times in a section having a measurement direction of 10 μm with a stylus having a very small tip radius, and is obtained from the average roughness regarding the amplitude of fine irregularities.

The emitted light h from the light emitting unit 13 is incident on the smoothing layer 11. For this reason, the average refractive index nf of the smoothing layer 11 is preferably a value close to the refractive index of the organic layer included in the light emitting unit 13. Specifically, the light emitting unit 13 is generally made of an organic material having a high refractive index. Therefore, the smoothing layer 11 has an average refractive index nf of 1.5 or more, particularly more than 1.65 and less than 2.5 at the shortest emission maximum wavelength among the emission maximum wavelengths of the emitted light h from the light emitting unit 13. A high refractive index layer is preferred. As long as the average refractive index nf is greater than 1.65 and less than 2.5, it may be formed of a single material or a mixture. When the smoothing layer 11 is a mixed system, the refractive index of each material may be 1.65 or less or 2.5 or more, and the average refractive index nf of the mixed film is greater than 1.65 and less than 2.5. It only has to satisfy.

The “average refractive index nf” of the smoothing layer 11 is the refractive index of a single material when it is formed of a single material. In the case of a mixed system, the mixing ratio is added to the refractive index specific to each material. It is a calculated refractive index calculated by the sum value multiplied by. The refractive index is measured by irradiating a light beam having the shortest light emission maximum wavelength among the light emission maximum wavelengths of the emitted light h from the light emitting unit 13 in an atmosphere of 25 ° C., and Abbe refractometer (manufactured by ATAGO, DR -M2).

As the binder used for the smoothing layer 11, a known resin can be used without any particular limitation. For example, acrylic ester, methacrylic ester, polyethylene terephthalate (PET), polybutylene terephthalate, polyethylene naphthalate (PEN), Polycarbonate (PC), polyarylate, polyvinyl chloride (PVC), polyethylene (PE), polypropylene (PP), polystyrene (PS), nylon (Ny), aromatic polyamide, polyether ether ketone, polysulfone, polyether sulfone, Resin films such as polyimide and polyetherimide, heat-resistant transparent films having an organic-inorganic hybrid structure and having a basic skeleton of silsesquioxane, polysiloxane, polysilazane, polysiloxazan, etc. (for example, Product name Sila-DEC (manufactured by Chisso Corporation), perfluoroalkyl group-containing silane compounds (for example, (heptadecafluoro-1,1,2,2-tetradecyl) triethoxysilane), crosslinkability with fluorine-containing monomers Examples thereof include a fluorinated copolymer having a monomer for group addition as a structural unit. These resins can be used in combination of two or more. Among these, those having an organic-inorganic hybrid structure are preferable.

Further, as the binder used for the smoothing layer 11, the following hydrophilic resins can be used. Examples of the hydrophilic resin include water-soluble resins, water-dispersible resins, colloid-dispersed resins, and mixtures thereof. Examples of the hydrophilic resin include acrylic resins, polyester resins, polyamide resins, polyurethane resins, fluorine resins, etc., for example, polyvinyl alcohol, gelatin, polyethylene oxide, polyvinyl pyrrolidone, casein, starch, agar, carrageenan, polyacrylic. Polymers such as acid, polymethacrylic acid, polyacrylamide, polymethacrylamide, polystyrene sulfonic acid, cellulose, hydroxyl ethyl cellulose, carboxyl methyl cellulose, hydroxyl ethyl cellulose, dextran, dextrin, pullulan, water-soluble polyvinyl butyral can be mentioned, but these Among these, polyvinyl alcohol is preferable. As the polymer used as the binder resin, one type may be used alone, or two or more types may be mixed and used as necessary. Similarly, conventionally known resin particles (emulsion) and the like can also be suitably used as the binder.

Also, as the binder, a resin curable mainly by ultraviolet rays or an electron beam, that is, a mixture of a thermoplastic resin and a solvent in an ionizing radiation curable resin or a thermosetting resin can be suitably used. Such a binder resin is preferably a polymer having a saturated hydrocarbon or polyether as a main chain, and more preferably a polymer having a saturated hydrocarbon as a main chain.

Also, the binder is preferably crosslinked. The polymer having a saturated hydrocarbon as the main chain is preferably obtained by a polymerization reaction of an ethylenically unsaturated monomer. In order to obtain a crosslinked binder, it is preferable to use a monomer having two or more ethylenically unsaturated groups.

The smoothing layer 11 can be produced as follows. First, a dispersion liquid in which nano-TiO ₂ particles are dispersed and a resin solution are mixed and filtered through a filter to obtain a solution for preparing the smoothing layer 11. And the smoothing layer 11 can be produced by apply | coating the preparation solution of the smoothing layer 11 on the gas-barrier film 20 formed to the light-scattering layer 14, drying, and heating.

[Light scattering layer]
In the light scattering layer 14 formed in the organic EL element 10, the emitted light h from the light emitting unit 13 enters through the smoothing layer 11. For this reason, the average refractive index ns of the light scattering layer 14 is preferably as close as possible to the organic layer of the light emitting unit 13 and the adjacent smoothing layer 11. The average refractive index ns of the light scattering layer 14 is within the range of 1.5 or more, particularly 1.6 or more and less than 2.5 at the shortest emission maximum wavelength among the emission maximum wavelengths of the emitted light h from the light emitting unit 13. Preferably there is. In this case, the light scattering layer 14 may be formed alone using a material having an average refractive index ns of 1.6 or more and less than 2.5, or formed using a mixture of two or more materials. May be. When the light-scattering layer 14 is a mixed system, the average refractive index ns of the light-scattering layer 14 uses a calculated refractive index that is calculated by adding a refractive index specific to each material and a mixing ratio. In this case, the refractive index of each material may be less than 1.6 or 2.5 or more as long as the average refractive index ns of the mixed film satisfies 1.6 or more and less than 2.5. Good.
Here, the “average refractive index ns” is the refractive index of a single material when formed of a single material, and in the case of a mixed system, the refractive index specific to each material is multiplied by the mixing ratio. It is the calculated refractive index calculated by the combined value.

The light scattering layer 14 is a layer that improves light extraction efficiency, and is preferably formed on the outermost surface of the gas barrier film 20 on the first electrode 12 side. The light scattering layer 14 is preferably a mixture of a binder that is a layer medium and light scattering particles. The light scattering layer 14 is preferably a scattering film using a refractive index difference by a mixture of a binder having a lower refractive index than the light scattering particles and a light scattering particle having a higher refractive index than the binder.

The binder having a low refractive index has a refractive index nb of less than 1.9, particularly preferably less than 1.6. The refractive index nb of the binder is the refractive index of a single material when it is formed of a single material. In the case of a mixed system, the refractive index nb is calculated by adding the refractive index specific to each material and the mixing ratio. Is the calculated refractive index.

Further, the light scattering particles have a refractive index np of 1.5 or more, preferably 1.8 or more, and particularly preferably 2.0 or more. The refractive index np of the light scattering particle is the refractive index of a single material when it is formed of a single material. In the case of a mixed system, the total refractive index of each material is multiplied by the mixing ratio. Calculated refractive index calculated by value.

Further, the role of the light scattering particles of the light scattering layer 14 includes a guided light scattering function. In order to improve the guided light scattering function, it is conceivable to increase the refractive index difference between the light scattering particles and the binder, increase the layer thickness, and increase the particle density. Among them, the one with the smallest trade-off with other performance is to increase the difference in refractive index between the light scattering particles and the binder.

The refractive index difference | nb−np | between the binder as the layer medium and the contained light scattering particles is preferably 0.2 or more, and particularly preferably 0.3 or more. When the refractive index difference | nb−np | between the layer medium and the light scattering particles is 0.03 or more, a scattering effect occurs at the interface between the layer medium and the light scattering particles. A larger refractive index difference | nb−np | is preferable because refraction at the interface increases and the scattering effect is improved. Specifically, it is preferably a high refractive index layer in which the average refractive index ns of the light scattering layer 14 is in the range of 1.6 or more and less than 2.5. For this reason, for example, the refractive index nb of the binder is preferably smaller than 1.6, and the refractive index np of the light scattering particles is preferably larger than 1.8. The refractive index is measured in the same manner as the smoothing layer 11 by irradiating a light beam having the shortest light emission maximum wavelength among the light emission maximum wavelengths of the emitted light h from the light emitting unit 13 in an atmosphere at 25 ° C. The measurement was performed using a rate meter (manufactured by ATAGO, DR-M2).

The layer thickness of the light scattering layer 14 needs to be thick to some extent in order to ensure the optical path length for causing scattering. On the other hand, it should be thin enough not to cause energy loss due to absorption. Specifically, the thickness of the light scattering layer 14 is preferably in the range of 0.1 to 5 μm, and more preferably in the range of 0.2 to 2 μm.

[Light scattering particles]
As described above, the light scattering layer 14 is preferably a layer that diffuses light due to a difference in refractive index between the layer medium and the light scattering particles. For this reason, the contained light scattering particles are required to scatter the emitted light h from the light emitting unit 13 without adversely affecting other layers. Scattering particles are actually polydisperse particles and difficult to arrange regularly, so they have a diffraction effect locally, but in many cases, the direction of light is changed by diffusion to improve light extraction efficiency. Improve.

Scattering represents a state in which the haze value of the single layer of the light scattering layer 14 (the ratio of the scattering transmittance to the total light transmittance) is 20% or more, more preferably 25% or more, and particularly preferably 30% or more. . If the haze value is 20% or more, the luminous efficiency can be improved. The haze value is a physical property value calculated under the influence of (i) the influence of the refractive index difference of the composition in the film and (ii) the influence of the surface shape. That is, by measuring the haze value while suppressing the surface roughness below a certain level, the haze value excluding the influence of (ii) is measured. Specifically, it can be measured using a haze meter (manufactured by Nippon Denshoku Industries Co., Ltd., NDH-5000, etc.).

For example, the light scattering layer 14 can improve the light scattering property by adjusting the particle diameter of the light scattering particles, and can suppress defects such as a short circuit. Specifically, it is preferable to use transparent light scattering particles having a particle diameter equal to or larger than a region that causes Mie scattering in the visible light region.

The average particle diameter of the light scattering particles is preferably 0.2 μm or more. If the average particle diameter of the light scattering particles is too large, the adjacent smoothing layer 11 for flattening the roughness of the light scattering layer 14 containing the light scattering particles also needs to be thickened. There are disadvantages in terms of absorption. For this reason, it is preferable that the average particle diameter of light-scattering particle | grains is less than 1 micrometer. The average particle diameter of the light scattering particles can be measured, for example, by an apparatus using a dynamic light scattering method such as Nanotrack UPA-EX150 manufactured by Nikkiso Co., Ltd., or by image processing of an electron micrograph.

Further, when a plurality of types of particles are used for the light scattering layer 14, in addition to the light scattering particles having a particle size in the above range, at least one kind of light scattering particles having an average particle diameter in the range of 100 nm to 3 μm is included, and 3 μm. It is preferable that the above light scattering particles are not included, and it is particularly preferable that at least one kind of light scattering particles within a range of 200 nm to 1 μm is included and light scattering particles of 1 μm or more are not included.

The material of such light scattering particles is not particularly limited and can be appropriately selected according to the purpose. For example, organic fine particles or inorganic fine particles may be used. In particular, the light scattering particles are preferably inorganic fine particles having a high refractive index. In addition, quantum dots described in International Publication No. 2009/014707 and US Pat. No. 6,608,439 can also be suitably used as light scattering particles.

Examples of organic fine particles having a high refractive index include polymethyl methacrylate beads, acrylic-styrene copolymer beads, melamine beads, polycarbonate beads, styrene beads, cross-linked polystyrene beads, polyvinyl chloride beads, benzoguanamine-melamine formaldehyde beads, and the like. Can be mentioned.

Examples of the inorganic fine particles having a high refractive index include inorganic oxide particles made of at least one oxide selected from zirconium, titanium, aluminum, indium, zinc, tin, antimony and the like. Specific examples of inorganic oxide particles include ZrO ₂ , TiO ₂ , BaTiO ₃ , Al ₂ O ₃ , In ₂ O ₃ , ZnO, SnO ₂ , Sb ₂ O ₃ , ITO, SiO ₂ , ZrSiO ₄ , zeolite, and the like. Is mentioned. Among these, TiO ₂ , BaTiO ₃ , ZrO ₂ , ZnO and SnO ₂ are preferable, and TiO ₂ is most preferable. Of TiO _2, the rutile type is more preferable than the anatase type because the weather resistance of the light scattering layer 14 and the adjacent layer is high because the catalytic activity is low, and the refractive index is high.

Further, these light scattering particles may be used after being subjected to a surface treatment from the viewpoint of improving the dispersibility and stability of the dispersion containing the light scattering particles. When performing the surface treatment, specific materials for the surface treatment include different inorganic oxides such as silicon oxide and zirconium oxide, metal hydroxides such as aluminum hydroxide, organic acids such as organosiloxane and stearic acid, and the like. It is done. These surface treatment materials may be used individually by 1 type, and may be used in combination of multiple types. Among these, from the viewpoint of the stability of the dispersion, the surface treatment material is preferably a different inorganic oxide and / or metal hydroxide, more preferably a metal hydroxide.

When the inorganic oxide particles are surface-coated with a surface treatment material, the coating amount is preferably 0.01 to 99% by mass. By making the coating amount within this range, the effect of improving the dispersibility and stability by the surface treatment can be sufficiently obtained, and the light extraction efficiency can be improved by the high refractive index of the light scattering layer 14. . Generally, the coating amount is indicated by the mass ratio of the surface treatment material used on the surface of the particle with respect to the mass of the particle.

The light scattering particles are arranged in a layer thickness corresponding to one light scattering particle so that the light scattering particles are in contact with or close to the interface between the light scattering layer 14 and the adjacent smoothing layer 11. Is preferred. Thereby, when total reflection occurs at the interface between the smoothing layer 11 and the light scattering layer 14, the evanescent light that oozes out to the light scattering layer 14 can be scattered by the light scattering particles, and the light extraction efficiency is improved. improves.

The content of the high refractive index particles in the light scattering layer 14 is preferably in the range of 1.0 to 70%, more preferably in the range of 5.0 to 50% in terms of volume filling factor. As a result, the refractive index distribution can be made sparse / dense at the smoothing layer 11 adjacent to the light scattering layer 14 or the interface between the smoothing layer 11, and the light extraction efficiency can be improved by increasing the amount of light scattering. .

As a method for forming the light scattering layer 14, for example, when the layer medium is a resin material, the light scattering particles are dispersed in a resin material (polymer) solution serving as a medium and applied onto the resin substrate 21. . At this time, a solvent in which particles are not dissolved is used as the solvent.

[binder]
Examples of the binder used for the light scattering layer 14 include the same resin as that of the smoothing layer 11.
In the light scattering layer 14, a compound capable of forming a metal oxide, a metal nitride, or a metal oxynitride by ultraviolet irradiation under a specific atmosphere is particularly preferably used. As this compound, a compound which can be modified at a relatively low temperature described in JP-A-8-112879 is preferable.

Specific examples of compounds that can be modified at low temperatures include polysiloxanes having Si—O—Si bonds (including polysilsesquioxane), polysilazanes having Si—N—Si bonds, and Si—O—Si bonds. And polysiloxazan containing both Si and N—Si bonds. These can be used in combination of two or more. Further, different compounds can be used by sequentially laminating or simultaneously laminating.

(Polysiloxane)
The polysiloxane used in the light scattering layer 14 can include [R ₃ SiO _1/2 ], [R ₂ SiO], [RSiO _3/2 ], and [SiO ₂ ] as general structural units. Here, R represents a hydrogen atom, an alkyl group containing 1 to 20 carbon atoms (for example, methyl, ethyl, propyl, etc.), an aryl group (for example, phenyl), and an unsaturated alkyl group (for example, vinyl). Independently selected from the group consisting of Examples of specific polysiloxane groups include [PhSiO _3/2 ], [MeSiO _3/2 ], [HSiO _3/2 ], [MePhSiO], [Ph ₂ SiO], [PhViSiO], [ViSiO _3/2 ]. (Vi represents a vinyl group), [MeHSiO], [MeViSiO], [Me ₂ SiO], [Me ₃ SiO _1/2 ] and the like. Mixtures and copolymers of polysiloxanes can also be used.

(Polysilsesquioxane)
In the light scattering layer 14, it is preferable to use polysilsesquioxane among the above-mentioned polysiloxanes. Polysilsesquioxane is a compound containing silsesquioxane in a structural unit. The “silsesquioxane” is a compound represented by [RSiO _3/2 ] and is usually represented by RSiX ₃ . Here, R is a hydrogen atom, an alkyl group, an alkenyl group, an aryl group, an aralkyl group (also referred to as an aralkyl group), and the like, and X is a halogen, an alkoxy group, or the like.
The molecular arrangement of polysilsesquioxane is typically an amorphous structure, a ladder structure, a cage structure, or a partially cleaved structure (a structure in which a silicon atom is missing from a cage structure or a cage structure). A structure in which the silicon-oxygen bond in the structure is partially broken) is known.

Among these polysilsesquioxanes, it is preferable to use a so-called hydrogen silsesquioxane polymer. Examples of the hydrogen silsesquioxane polymer include a hydridosiloxane polymer represented by HSi (OH) _x (OR) _y O _{z / 2} . Each R is an organic group or a substituted organic group, and forms a hydrolyzable substituent when bonded to silicon by an oxygen atom. Further, x = 0 to 2, y = 0 to 2, z = 1 to 3, and x + y + z = 3. Examples of R include an alkyl group (eg, methyl group, ethyl group, propyl group, butyl group), an aryl group (eg, phenyl group), and an alkenyl group (eg, allyl group, vinyl group). These resins may be fully condensed (HSiO _3/2 ) _n , or only partially hydrolyzed (ie, including some Si—OR) and / or partially condensed (ie, , Including some Si—OH).

(Polysilazane)
The polysilazane used in the light scattering layer 14 is a polymer having a silicon-nitrogen bond, and is composed of Si—N, Si—H, NH, etc., SiO ₂ , Si ₃ N _4, and both intermediate solid solutions SiO _x N _y. Inorganic precursor polymers such as (x = 0.1 to 1.9, y = 0.1 to 13).

As the polysilazane preferably used for the light scattering layer 14, the polysilazane represented by the above general formula (I) can be used as in the above-described light scattering layer 14. Perhydropolysilazane (PHPS) in which all of R ¹ , R ² and R ³ are hydrogen atoms is particularly preferred from the viewpoint of the denseness of the resulting light scattering layer 14 as a film. Perhydropolysilazane is presumed to have a linear structure and a ring structure centered on 6-membered and 8-membered rings, and its molecular weight is about 600 to 2000 in terms of number average molecular weight (Mn) (gel Polystyrene conversion by permeation chromatography), which is a liquid or solid substance.

Polysilazane is commercially available in the form of a solution dissolved in an organic solvent, and the commercially available product can be used as a polysilazane-containing coating solution as it is. Examples of commercially available polysilazane solutions include NN120-20, NAX120-20, and NL120-20 manufactured by AZ Electronic Materials.

Further, as the binder, an ionizing radiation curable resin composition can be used. As a curing method of the ionizing radiation curable resin composition, a normal curing method of the ionizing radiation curable resin composition, that is, an electron beam or It can be cured by UV irradiation. For example, in the case of electron beam curing, 10 to 1000 keV emitted from various electron beam accelerators such as a Cockrowalton type, a bandegraph type, a resonant transformation type, an insulating core transformer type, a linear type, a dynamitron type, and a high frequency type. Preferably, an electron beam having an energy of 30 to 300 keV is used, and in the case of ultraviolet curing, ultraviolet rays emitted from rays of ultra-high pressure mercury lamp, high pressure mercury lamp, low pressure mercury lamp, carbon arc, xenon arc, metal halide lamp, etc. Available.

(Vacuum ultraviolet irradiation device with excimer lamp)
Examples of the ultraviolet irradiation device include a rare gas excimer lamp that emits vacuum ultraviolet rays within a range of 100 to 230 nm. Atoms of noble gases such as xenon (Xe), krypton (Kr), argon (Ar), neon (Ne) and the like are called inert gases because they do not form molecules by chemically bonding. However, rare gas atoms (excited atoms) that have gained energy by discharge or the like can be combined with other atoms to form molecules.

For example, when the rare gas is Xe (xenon), excimer light of 172 nm is emitted when the excited excimer molecule Xe ₂ ^* transitions to the ground state, as shown in the following reaction formula.

e + Xe → Xe ^*
Xe ^* + 2Xe → Xe ₂ ^* + Xe
Xe ₂ ^* → Xe + Xe + hν (172 nm)

¡Excimer lamps are characterized by high efficiency because radiation concentrates on one wavelength and almost no other light is emitted. Moreover, since extra light is not radiated | emitted, the temperature of a target object can be kept comparatively low. Furthermore, since no time is required for starting and restarting, instantaneous lighting and blinking are possible.

As a light source for efficiently irradiating excimer light, there is a dielectric barrier discharge lamp. A dielectric barrier discharge lamp has a structure in which a discharge is generated between electrodes via a dielectric. Generally, at least one electrode is disposed between a discharge vessel made of a dielectric and the outside thereof. That's fine. As a dielectric barrier discharge lamp, for example, a rare gas such as xenon is enclosed in a double cylindrical discharge vessel composed of a thick tube and a thin tube made of quartz glass, and a net-like second discharge vessel is formed outside the discharge vessel. There is one in which one electrode is provided and another electrode is provided inside the inner tube. A dielectric barrier discharge lamp generates a dielectric barrier discharge inside a discharge vessel by applying a high frequency voltage between electrodes, and generates excimer light when excimer molecules such as xenon generated by the discharge dissociate. .

In addition, in order to further capture the light taken into the adjacent smoothing layer 11 into the light scattering layer 14, it is preferable that the refractive index difference between the binder of the light scattering layer 14 and the adjacent smoothing layer 11 is small. Specifically, the refractive index difference between the binder of the light scattering layer 14 and the smoothing layer 11 is preferably 0.1 or less. Moreover, it is preferable to use the same material for the binder contained in the smoothing layer 11 and the light scattering layer 14.

Further, by adjusting the thickness of the light scattering layer 14 and the smoothing layer 11 added, it is possible to suppress the wiring failure due to the ingress of moisture or the edge step when patterning, thereby improving the scattering property. Specifically, the thickness obtained by adding the smoothing layer 11 to the light scattering layer 14 is preferably in the range of 100 nm to 5 μm, and more preferably in the range of 300 nm to 2 μm.

[First electrode, second electrode]
The organic EL element 10 includes a light emitting unit 13 sandwiched between a pair of electrodes including a first electrode 12 and a second electrode 15. One of the first electrode 12 and the second electrode 15 serves as the anode of the organic EL element 10, and the other serves as the cathode. Hereinafter, the anode and the cathode will be described.

[anode]
As the anode in the organic EL element 10, an electrode material made of a metal, an alloy, an electrically conductive compound, or a mixture thereof having a high work function (4 eV or more) is preferably used. Specific examples of such an electrode substance include conductive transparent materials such as metals such as Au and Ag, CuI, indium tin oxide (ITO), SnO ₂ , and ZnO. Alternatively, an amorphous material such as IDIXO (In ₂ O ₃ —ZnO) capable of forming a transparent conductive film may be used.

For the anode, a thin film may be formed by depositing these electrode materials by a method such as vapor deposition or sputtering, and a pattern having a desired shape may be formed by photolithography, or when the pattern accuracy is not so high (about 100 μm or more) ), A pattern may be formed through a mask having a desired shape when the electrode material is deposited or sputtered.

In the case of using a coatable material such as an organic conductive compound, a wet film forming method such as a printing method or a coating method can be used. When light emission is extracted from the anode side, it is desirable that the transmittance be greater than 10%. The sheet resistance as the anode is several hundred Ω / sq. The following is preferred. Although the film thickness depends on the material, it is usually selected within the range of 10 to 1000 nm, preferably within the range of 10 to 200 nm.
[cathode]
The cathode is an electrode film that functions as a cathode (cathode) that supplies electrons to the light emitting unit 13. As the cathode, a material having a work function (4 eV or less) metal (referred to as an electron injecting metal), an alloy, an electrically conductive compound, and a mixture thereof as an electrode material is used.
Specific examples of such electrode materials include 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 ) Mixtures, indium, lithium / aluminum mixtures, rare earth metals and the like.

Among these, from the point of durability against electron injection and oxidation, etc., a mixture of an electron injecting metal and a second metal which is a stable metal having a larger work function than this, for example, a magnesium / silver mixture, A magnesium / aluminum mixture, a magnesium / indium mixture, an aluminum / aluminum oxide (Al ₂ O ₃ ) mixture, a lithium / aluminum mixture, aluminum, or the like is preferable. The cathode can be produced by forming a thin film of these electrode materials by a method such as vapor deposition or sputtering.

The sheet resistance as a cathode is several hundred Ω / sq. The film thickness is usually selected from the range of 10 nm to 5 μm, preferably 50 to 200 nm. Further, after producing the above metal as a cathode with a film thickness of 1 to 20 nm, a transparent or semitransparent cathode can be produced by producing the conductive transparent material mentioned in the description of the anode thereon. By applying this, an element in which both the anode and the cathode are transmissive can be manufactured.

[Auxiliary electrode]
The auxiliary electrode 18 is provided for the purpose of reducing the resistance of the first electrode 12 and is preferably provided in contact with the first electrode 12. The material for forming the auxiliary electrode 18 is preferably a metal with low resistance such as gold, platinum, silver, copper, or aluminum. Since these metals have low light transmittance, a pattern is formed in a range that does not affect the extraction of the emitted light h from the light extraction surface.

The line width of the auxiliary electrode 18 is preferably 50 μm or less from the viewpoint of the aperture ratio for extracting light, and the thickness of the auxiliary electrode 18 is preferably 1 μm or more from the viewpoint of conductivity. Examples of the method for forming the auxiliary electrode 18 include a vapor deposition method, a sputtering method, a printing method, an ink jet method, and an aerosol jet method.

[Extraction electrode]
The extraction electrode 16 is for electrically connecting the first electrode 12 and an external power source, and the material thereof is not particularly limited, and a known material can be preferably used. A metal film such as a MAM electrode (Mo / Al · Nd alloy / Mo) made of can be used.

[Light emitting unit]
The light emitting unit 13 is a light emitting body (unit) composed mainly of at least a light emitting layer containing a light emitting material made of various organic compounds. The light emitting unit 13 is sandwiched between a pair of electrodes composed of an anode and a cathode, and holes supplied from the anode and electrons supplied from the cathode are recombined in the light emitter. Emits light. The organic EL element 10 may include a plurality of the light emitting units 13 according to a desired light emission color.

The organic EL element 10 may be an element having a so-called tandem structure in which a plurality of light emitting units 13 including at least one light emitting layer are stacked. Examples of typical element configurations of the tandem structure include the following configurations.
Anode / first light emitting unit / intermediate connector layer / second light emitting unit / intermediate connector layer / third light emitting unit / cathode

Here, the first light emitting unit, the second light emitting unit, and the third light emitting unit may all be the same or different. Further, the two light emitting units may be the same, and the remaining one may be different.
The plurality of light emitting units 13 may be directly stacked or may be stacked via an intermediate connector layer.

The intermediate connector layer is also commonly referred to as an intermediate electrode, intermediate conductive layer, charge generation layer, electron extraction layer, connection layer, or intermediate insulating layer. Electrons are transferred to the anode side adjacent layer and holes are connected to the cathode side adjacent layer. A known material structure can be used as long as the layer has a function of supplying. Examples of materials used for the intermediate connector layer include ITO (indium tin oxide), IZO (indium zinc oxide), ZnO ₂ , TiN, ZrN, HfN, TiO _x , VO _x , CuI, InN, and GaN. , CuAlO ₂ , CuGaO ₂ , SrCu ₂ O ₂ , LaB ₆ , RuO ₂ , Al and other conductive inorganic compound layers, Au / Bi ₂ O _{3 and} other two-layer films, SnO ₂ / Ag / SnO ₂ , ZnO / Ag / ZnO, Bi ₂ O ₃ / Au / Bi ₂ O ₃ , TiO ₂ / TiN / TiO ₂ , TiO ₂ / ZrN / TiO _{2 and} other multilayer films, C _{60 and} other fullerenes, oligothiophene and other conductive materials Conductive organic compound layers such as conductive organic layers, metal phthalocyanines, metal-free phthalocyanines, metal porphyrins, metal-free porphyrins, etc. It is, but is not limited thereto.

Examples of a preferable configuration in the light emitting unit 13 include, but are not limited to, a configuration in which the anode and the cathode are removed from the configuration described in the representative element configuration.
Specific examples of the tandem organic EL element include, for example, US Pat. No. 6,337,492, US Pat. No. 7,420,203, US Pat. No. 7,473,923, US Pat. No. 6,872,472, US Pat. No. 6,107,734. Specification, U.S. Pat. No. 6,337,492, International Publication No. 2005/009087, JP-A-2006-228712, JP-A-2006-24791, JP-A-2006-49393, JP-A-2006-49394 JP-A-2006-49396, JP-A-2011-96679, JP-A-2005-340187, JP-A-4711424, JP-A-3496868, JP-A-3848564, JP-A-4421169, JP 2010-192719, JP 009-076929, JP 2008-078414, JP 2007-059848, JP 2003-272860, JP 2003-045676, WO 2005/094130, etc. Examples of the structure and constituent materials are given.

[Light emitting layer]
The light emitting layer 13c is a layer that emits light by recombination of electrons injected from the electron transport layer 13d and holes injected from the hole transport layer 13b, and the light emitting portion is within the layer of the light emitting layer 13c. Even if it exists, the interface of the light emitting layer 13c and the adjacent layer may be sufficient.

The configuration of the light emitting layer 13c is not particularly limited as long as the light emitting material included satisfies the light emission requirements. Moreover, there may be a plurality of layers having the same emission spectrum and emission maximum wavelength. In this case, it is preferable to have a non-light emitting auxiliary layer (not shown) between the light emitting layers 13c.

The total thickness of the light emitting layer 13c is preferably in the range of 1 to 100 nm, and more preferably in the range of 1 to 30 nm because a lower driving voltage can be obtained. The total layer thickness of the light emitting layer 13c is a layer thickness including the intermediate layer when a non-light emitting intermediate layer exists between the light emitting layers 13c.

In the case of the light emitting layer 13c having a structure in which a plurality of layers are laminated, the thickness of each light emitting layer is preferably adjusted within a range of 1 to 50 nm, and more preferably within a range of 1 to 20 nm. When the plurality of stacked light emitting layers correspond to the respective emission colors of blue, green, and red, there is no particular limitation on the relationship between the thicknesses of the blue, green, and red light emitting layers.

The structure of the light emitting layer 13c preferably contains a host compound (light emitting host or the like) and a light emitting material (light emitting dopant) and emits light from the light emitting material. The light emitting layer 13c may be a mixture of a plurality of light emitting materials. For example, a phosphorescent compound (phosphorescent compound, phosphorescent light emitting material) and a fluorescent light emitting material (fluorescent dopant, fluorescent compound) emit the same light. You may mix and use in the layer 13c. The light emitting layer 13c preferably contains a phosphorescent light emitting compound as a light emitting material. The light emitting layer 13c can be formed by forming a light emitting material or a host compound described later by a known thin film forming method such as a vacuum deposition method, a spin coating method, a casting method, an LB method, or an ink jet method.

(1. Host compound)
As a host compound contained in the light emitting layer 13c, a compound having a phosphorescence quantum yield of phosphorescence emission at room temperature (25 ° C.) of less than 0.1 is preferable. More preferably, the phosphorescence quantum yield is less than 0.01. Moreover, it is preferable that the volume ratio in the layer is 50% or more among the compounds contained in the light emitting layer 13c.

As the host compound, a known host compound may be used alone, or a plurality of types may be used. By using a plurality of types of host compounds, it is possible to adjust the movement of charges, and the organic EL element can be made highly efficient. In addition, by using a plurality of kinds of light emitting materials described later, it is possible to mix different light emission, thereby obtaining an arbitrary light emission color.

The host compound may be a conventionally known low molecular compound, a high molecular compound having a repeating unit, or a low molecular compound having a polymerizable group such as a vinyl group or an epoxy group (evaporation polymerizable light emitting host).

The known host compound is preferably a compound that has a hole transporting ability and an electron transporting ability, prevents the emission of light from becoming longer, and has a high Tg (glass transition temperature).
The glass transition point (Tg) here is a value determined by a method based on JIS K 7121 using DSC (Differential Scanning Calorimetry).

As specific examples of known host compounds, compounds described in the following documents can be used. For example, Japanese Patent Application Laid-Open Nos. 2010-251675, 2001-257076, 2002-308855, 2001131179, 2002-319491, 2001359777, 2002-334786, 2002-8860, 2002-334787, 2002-15871, 2002-334788, 2002-43056, 2002-334789, 2002-75645, 2002 -338579, 2002-105445, 2002-343568, 2002-141173, 2002-352957, 2002-203683, 2002-363227 No. 2002-231453, No. 2003-3165, No. 2002-234888, No. 2003-27048, No. 2002-255934, No. 2002-286061, No. 2002-280183, No. 2002-299060, No. 2002-302516, No. 2002-305083, No. 2002-305084, No. 2002-308837, and the like.

(2. Luminescent material)
Examples of the light emitting material include phosphorescent compounds (phosphorescent compounds and phosphorescent materials) and fluorescent compounds (fluorescent compounds and fluorescent materials).

(Phosphorescent compound)
A phosphorescent compound is a compound in which light emission from an excited triplet is observed. Specifically, it is a compound that emits phosphorescence at room temperature (25 ° C.), and is defined as a compound having a phosphorescence quantum yield of 0.01 or more at 25 ° C. A preferable phosphorescence quantum yield is 0.1 or more.

The phosphorescent quantum yield can be measured by the method described in Spectroscopic II, page 398 (1992 edition, Maruzen) of Experimental Chemistry Course 4 of the 4th edition. The phosphorescence quantum yield in solution can be measured using various solvents, but when using a phosphorescent compound, the above phosphorescence quantum yield (0.01 or more) can be achieved in any solvent. That's fine.

There are two types of light emission principle of the phosphorescent compound.
One is that recombination of carriers occurs on the host compound to which carriers are transported to generate an excited state of the host compound, and this energy is transferred to the phosphorescent compound to emit light from the phosphorescent compound. Energy transfer type.
The other is a carrier trap type in which a phosphorescent compound serves as a carrier trap, carrier recombination occurs on the phosphorescent compound, and light emission from the phosphorescent compound is obtained.
In either case, the condition is that the excited state energy of the phosphorescent compound is lower than the excited state energy of the host compound.

The phosphorescent compound can be appropriately selected from those used in a light emitting layer of a general organic EL device. Preferred are complex compounds containing a group 8-10 metal in the periodic table of elements, and more preferred are iridium compounds, osmium compounds, platinum compounds (platinum complex compounds) or rare earth complexes. In particular, iridium compounds are preferred.
Specific examples of the phosphorescent compound include, but are not limited to, compounds described in JP2010-251675A.

The phosphorescent compound is preferably 0.1% by volume or more and less than 30% by volume with respect to the total amount of the light emitting layer 13c. The light emitting layer 13c may contain two or more phosphorescent compounds, and the concentration ratio of the phosphorescent compound in the light emitting layer 13c may change in the thickness direction of the light emitting layer 13c.

(Fluorescent compound)
Fluorescent compounds include coumarin dyes, pyran dyes, cyanine dyes, croconium dyes, squalium dyes, oxobenzanthracene dyes, fluorescein dyes, rhodamine dyes, pyrylium dyes, perylene dyes, stilbene dyes. System dyes, polythiophene dyes, rare earth complex phosphors, and the like.

[Injection layer: hole injection layer, electron injection layer]
The injection layer is a layer provided between the electrode and the light emitting layer 13c in order to lower the driving voltage and improve the light emission luminance. “The organic EL element and its industrialization front line (November 30, 1998 2) Chapter 2 “Electrode Materials” (pages 123 to 166) of the second edition of “TS Co., Ltd.”, which includes a hole injection layer 13a and an electron injection layer 13e.

The injection layer can be provided as necessary. The hole injection layer 13a may be present between the anode and the light emitting layer 13c or the hole transport layer 13b, and the electron injection layer 13e may be present between the cathode and the light emitting layer 13c or the electron transport layer 13d. .

The details of the hole injection layer 13a are described in JP-A-9-45479, JP-A-9-260062, JP-A-8-288069, and the like. Specific examples thereof include phthalocyanine represented by copper phthalocyanine. Examples thereof include a layer, an oxide layer typified by vanadium oxide, an amorphous carbon layer, and a polymer layer using a conductive polymer such as polyaniline (emeraldine) or polythiophene.

The details of the electron injection layer 13e are described in JP-A-6-325871, JP-A-9-17574, JP-A-10-74586, and the like, and specifically represented by strontium, aluminum, and the like. Examples thereof include a metal layer, an alkali metal halide layer typified by potassium fluoride, an alkaline earth metal compound layer typified by magnesium fluoride, and an oxide layer typified by molybdenum oxide. The electron injection layer 13e is preferably a very thin layer, and its layer thickness is preferably in the range of 1 nm to 10 μm, although it depends on the material.

[Hole transport layer]
The hole transport layer 13b is made of a hole transport material having a function of transporting holes, and in a broad sense, the hole injection layer 13a and the electron blocking layer are also included in the hole transport layer 13b.
The hole transport layer 13b can be provided as a single layer or a plurality of layers. The hole transport layer 13b may have a single layer structure composed of one or more of the following materials.

The hole transport material has either hole injection or transport or electron barrier properties, and may be either organic or inorganic. For example, triazole derivatives, oxadiazole derivatives, imidazole derivatives, polyarylalkane derivatives, pyrazoline derivatives and pyrazolone derivatives, phenylenediamine derivatives, arylamine derivatives, amino-substituted chalcone derivatives, oxazole derivatives, styrylanthracene derivatives, fluorenone derivatives, hydrazone derivatives, Examples thereof include stilbene derivatives, silazane derivatives, aniline copolymers, conductive polymer oligomers, particularly thiophene oligomers. In particular, it is preferable to use a porphyrin compound, an aromatic tertiary amine compound and a styrylamine compound, particularly an aromatic tertiary amine compound.

Representative examples of aromatic tertiary amine compounds and styrylamine compounds include N, N, N ′, N′-tetraphenyl-4,4′-diaminophenyl, N, N′-diphenyl-N, N′— Bis (3-methylphenyl)-[1,1'-biphenyl] -4,4'-diamine (TPD), 2,2-bis (4-di-p-tolylaminophenyl) propane, 1,1-bis (4-di-p-tolylaminophenyl) cyclohexane, N, N, N ′, N′-tetra-p-tolyl-4,4′-diaminobiphenyl, 1,1-bis (4-di-p-tolyl) Aminophenyl) -4-phenylcyclohexane, bis (4-dimethylamino-2-methylphenyl) phenylmethane, bis (4-di-p-tolylaminophenyl) phenylmethane, N, N'-diphenyl-N, N ' Di (4-methoxyphenyl) -4,4'-diaminobiphenyl, N, N, N ', N'-tetraphenyl-4,4'-diaminodiphenyl ether, 4,4'-bis (diphenylamino) quadriphenyl N, N, N-tri (p-tolyl) amine, 4- (di-p-tolylamino) -4 ′-[4- (di-p-tolylamino) styryl] stilbene, 4-N, N-diphenylamino -(2-diphenylvinyl) benzene, 3-methoxy-4'-N, N-diphenylaminostilbenzene, N-phenylcarbazole, and two condensed fragrances described in US Pat. No. 5,061,569 Having an aromatic ring in the molecule, for example, 4,4'-bis [N- (1-naphthyl) -N-phenylamino] biphenyl (NPD), JP-A-4-3086 4,4 ′, 4 ″ -tris [N- (3-methylphenyl) -N-phenylamino] triphenylamine in which triphenylamine units described in No. 8 publication are linked in three starburst types ( MTDATA) and the like.

Furthermore, polymer materials in which these materials are introduced into polymer chains or these materials are used as polymer main chains can also be used. In addition, inorganic compounds such as p-type-Si and p-type-SiC can also be used as the hole injection material and the hole transport material. Further, JP-A-11-251067, J. Org. Huang et. al. , Applied Physics Letters, 80 (2002), p. The so-called p-type hole transport material described in 139 can also be used. These materials are preferably used because a light emitting element with higher efficiency can be obtained.

It is also possible to increase the p property by doping impurities into the material of the hole transport layer 13b. For example, JP-A-4-297076, JP-A-2000-196140, 2001-102175, J. Pat. Appl. Phys. 95, 5773 (2004), and the like. When the p property of the hole transport layer 13b is increased, a device with lower power consumption can be manufactured.

The layer thickness of the hole transport layer 13b is not particularly limited, but is usually about 5 nm to 5 μm, preferably 5 to 200 nm.
The hole transport layer 13b is formed by thinning the hole transport material by a known method such as a vacuum deposition method, a spin coating method, a casting method, a printing method including an ink jet method, or an LB method. be able to.

[Electron transport layer]
The electron transport layer 13d is made of a material having a function of transporting electrons, and in a broad sense, the electron injection layer 13e and a hole blocking layer (not shown) are also included in the electron transport layer 13d.
The electron transport layer 13d can be provided as a single layer structure or a stacked structure of a plurality of layers. The electron transport layer 13d may have a single-layer structure made of one or more of the following materials.

In the electron transport layer 13d, the electron transport material (also serving as a hole blocking material) constituting the layer portion adjacent to the light emitting layer 13c has a function of transmitting electrons injected from the cathode to the light emitting layer 13c. That's fine. As such a material, any one of conventionally known compounds can be selected and used.
Examples thereof include nitro-substituted fluorene derivatives, diphenylquinone derivatives, thiopyran dioxide derivatives, carbodiimides, fluorenylidenemethane derivatives, anthraquinodimethane, anthrone derivatives, oxadiazole derivatives, and the like. Furthermore, in the oxadiazole derivative, a thiadiazole derivative in which the oxygen atom of the oxadiazole ring is substituted with a sulfur atom, and a quinoxaline derivative having a quinoxaline ring known as an electron-withdrawing group are also used as the material for the electron transport layer 13d. Can do. Furthermore, a polymer material in which these materials are introduced into a polymer chain or these materials are used as a polymer main chain can also be used.

In addition, metal complexes of 8-quinolinol derivatives such as tris (8-quinolinol) aluminum (Alq ₃ ), tris (5,7-dichloro-8-quinolinol) aluminum, tris (5,7-dibromo-8-quinolinol) Aluminum, tris (2-methyl-8-quinolinol) aluminum, tris (5-methyl-8-quinolinol) aluminum, bis (8-quinolinol) zinc (Znq), etc. and the central metals of these metal complexes are In, Mg, A metal complex replaced with Cu, Ca, Sn, Ga, or Pb can also be used as the material of the electron transport layer 13d.

In addition, metal-free or metal phthalocyanine, or those whose terminal is substituted with an alkyl group or a sulfonic acid group can be preferably used as the material for the electron transport layer 13d. Further, distyrylpyrazine derivatives used as the material of the light emitting layer 13c, and inorganic semiconductors such as n-type-Si and n-type-SiC similar to the hole injection layer 13a and the hole transport layer 13b are also included in the electron transport layer 13d. It can be used as a material.

Further, the electron transport layer 13d can be doped with impurities to increase the n property. Examples thereof include JP-A-4-297076, JP-A-10-270172, JP-A-2000-196140, 2001-102175, J.A. Appl. Phys. 95, 5773 (2004), and the like. Furthermore, it is preferable that the electron transport layer 13d contains potassium, a potassium compound, or the like. As the potassium compound, for example, potassium fluoride can be used. Thus, when the n property of the electron transport layer 13d is increased, an element with lower power consumption can be manufactured.

The layer thickness of the electron transport layer 13d is not particularly limited, but is usually about 5 nm to 5 μm, preferably 5 to 200 nm.
The electron transport layer 13d can be formed by thinning the above material by a known method such as a vacuum deposition method, a spin coating method, a casting method, a printing method including an ink jet method, or an LB method.

[Blocking layer: hole blocking layer, electron blocking layer]
The blocking layer is provided as necessary in addition to the basic constituent layer of the organic compound thin film. For example, as described in JP-A Nos. 11-204258 and 11-204359 and “Organic EL elements and the forefront of industrialization (published by NTT Corporation on November 30, 1998)”. There is a hole blocking layer. The thickness of the blocking layer is preferably in the range of 3 to 100 nm, and more preferably in the range of 5 to 30 nm.

The hole blocking layer has a function of the electron transport layer 13d in a broad sense. The hole blocking layer is made of a hole blocking material that has a function of transporting electrons but has a very small ability to transport holes, and recombines electrons and holes by blocking holes while transporting electrons. Probability can be improved. Moreover, the structure of the electron carrying layer 13d can be used as a hole-blocking layer as needed. The hole blocking layer is preferably provided adjacent to the light emitting layer 13c.

On the other hand, the electron blocking layer has a function of the hole transport layer 13b in a broad sense. The electron blocking layer is made of a material that has a function of transporting holes but has a very small ability to transport electrons. By blocking holes while transporting holes, the electron recombination probability is improved. Can be made. Moreover, the structure of the positive hole transport layer 13b can be used as an electron blocking layer as needed.

[Sealing member]
The sealing member 17 is a plate-like (film-like) member that covers the upper surface of the organic EL element 10, and is fixed to the resin base material 21 side by the adhesive layer 19. Further, the sealing member 17 may be a sealing film. Such a sealing member 17 is provided in a state in which the electrode terminal portion of the organic EL element 10 is exposed and at least the light emitting unit 13 is covered. Further, an electrode may be provided on the sealing member 17 so that the electrode terminal portion of the organic EL element 10 and the electrode of the sealing member 17 are electrically connected.

Specific examples of the plate-like (film-like) sealing member 17 include a glass substrate, a polymer substrate, a metal substrate, and the like. These substrates may be used in the form of a thin film. Examples of the glass substrate include soda lime glass, barium / strontium-containing glass, lead glass, aluminosilicate glass, borosilicate glass, barium borosilicate glass, and quartz. Examples of the polymer substrate include polycarbonate, acrylic, polyethylene terephthalate, polyether sulfide, and polysulfone. Examples of the metal substrate include those made of one or more metals or alloys selected from the group consisting of stainless steel, iron, copper, aluminum, magnesium, nickel, zinc, chromium, titanium, molybdenum, silicon, germanium, and tantalum. In particular, since the element can be thinned, it is preferable to use a polymer substrate or a metal substrate as a thin film as the sealing member.

Further, the substrate material may be processed into a concave plate shape and used as the sealing member 17. In this case, the substrate member described above is subjected to processing such as sandblasting and chemical etching to form a concave shape.

Further, the polymer substrate in the form of a film has an oxygen permeability measured by a method according to JIS K 7126-1987 of 1 × 10 ⁻³ ml / (m ² · 24 h · atm) or less, and conforms to JIS K 7129-1992. The water vapor permeability (25 ± 0.5 ° C., relative humidity (90 ± 2)% RH) measured by a compliant method is preferably 1 × 10 ⁻³ g / (m ² · 24 h) or less. .

Further, the adhesive layer 19 that fixes the sealing member 17 to the resin base material 21 side is used as a sealing agent for sealing the light emitting unit 13 with the sealing member 17 and the gas barrier film 20. Specific examples of the adhesive layer 19 include a photo-curing and thermosetting adhesive layer 19 having a reactive vinyl group of an acrylic acid-based oligomer or a methacrylic acid-based oligomer, a moisture-curing type such as 2-cyanoacrylate, and the like. The adhesive layer 19 can be mentioned.

Also, examples of the adhesive layer 19 include epoxy-based heat and chemical curing types (two-component mixing). Moreover, hot-melt type polyamide, polyester, and polyolefin can be mentioned. Further, the adhesive layer 19 can be exemplified by a cationic curing type ultraviolet curing epoxy resin.

Application | coating of the contact bonding layer 19 to the contact bonding layer 19 part of the sealing member 17 and the gas-barrier film 20 may use commercially available dispenser, and may print like screen printing.
In addition, the organic material which comprises an organic EL element may deteriorate with heat processing. For this reason, the adhesive layer 19 is preferably one that can cure the adhesive layer 19 from room temperature (25 ° C.) to 80 ° C. A desiccant may be dispersed in the adhesive layer 19.

Further, when a gap is formed between the plate-shaped sealing member 17 and the gas barrier film 20, in the gap and in the gas phase and the liquid phase, an inert gas such as nitrogen and argon, a fluorinated hydrocarbon, It is preferable to inject an inert liquid such as silicone oil. A vacuum can also be used. Moreover, a hygroscopic compound can also be enclosed inside.

Examples of the hygroscopic compound include metal oxides (for example, sodium oxide, potassium oxide, calcium oxide, barium oxide, magnesium oxide, aluminum oxide) and sulfates (for example, sodium sulfate, calcium sulfate, magnesium sulfate, cobalt sulfate). Etc.), metal halides (eg calcium chloride, magnesium chloride, cesium fluoride, tantalum fluoride, cerium bromide, magnesium bromide, barium iodide, magnesium iodide etc.), perchloric acids (eg perchloric acid) Barium, magnesium perchlorate, and the like), and anhydrous salts are preferably used in sulfates, metal halides, and perchloric acids.

On the other hand, when a sealing film is used as the sealing member 17, sealing is performed on the gas barrier film 20 in a state where the light emitting unit 13 in the organic EL element 10 is completely covered and the electrode terminal portion of the organic EL element 10 is exposed. A membrane is provided. Such a sealing film is configured using an inorganic material or an organic material. In particular, it is made of a material having a function of suppressing intrusion of a substance that causes deterioration of the light emitting unit 13 in the organic EL element 10 such as moisture and oxygen. As such a material, for example, inorganic materials such as silicon oxide, silicon dioxide, and silicon nitride are used. Furthermore, in order to improve the brittleness of the sealing film, a laminated structure may be formed by using a film made of an organic material together with a film made of these inorganic materials.

The method for forming these films is not particularly limited. For example, vacuum deposition method, sputtering method, reactive sputtering method, molecular beam epitaxy method, cluster ion beam method, ion plating method, plasma polymerization method, atmospheric pressure plasma A polymerization method, a plasma CVD method, a laser CVD method, a thermal CVD method, a coating method, or the like can be used.

[Protective member]
Although illustration is omitted here, a protective member such as a protective film or a protective plate for mechanically protecting the organic EL element 10 may be provided. The protective member is disposed at a position where the organic EL element 10 and the sealing member 17 are sandwiched between the gas barrier film 20. In particular, when the sealing member 17 is a sealing film, mechanical protection for the organic EL element 10 is not sufficient, and thus such a protective member is preferably provided.

For the protective member as described above, a glass plate, a polymer plate, a thinner polymer film, a metal plate, a thinner metal film, or a polymer material film or a metal material film is applied. Among these, it is particularly preferable to use a polymer film because it is lightweight and thin.

[Method of manufacturing organic EL element]
Next, an example of a method for manufacturing the organic EL element 10 will be described.
First, the gas barrier layer 22 is formed on the resin base material 21. First, a coating film containing polysilazane is formed on the resin base material 21, and after the coating film is dried, a modification treatment by vacuum ultraviolet irradiation is performed to form a silicon-containing layer 23 containing silicon and nitrogen. And the metal containing layer 24 containing the compound of the metal M is formed on the silicon containing layer 23 using a vapor phase film-forming method. Thereby, the gas barrier layer 22 including the silicon-containing layer 23 and the metal-containing layer 24 is formed. At this time, the region A described above is preferably formed in the vicinity of the interface between the silicon-containing layer 23 and the metal-containing layer 24.

Next, a resin material solution in which light scattering particles having an average particle diameter of 0.2 μm or more are dispersed is applied on the gas barrier layer 22 to form the light scattering layer 14. Next, the smoothing layer 11 mainly composed of silicon or niobium oxide or nitride is formed on the light scattering layer 14 by a dry process or a wet process.

Next, an appropriate method such as a vapor deposition method is applied so that the first electrode 12 made of silver or an alloy containing silver as a main component is formed on the smoothing layer 11 so as to have a layer thickness of 12 nm or less, preferably 4 to 9 nm. To form a first electrode 12 which is formed on the underlying layer and serves as an anode. At the same time, the extraction electrode 16 connected to the external power source is formed at the end of the first electrode 12 by an appropriate method such as vapor deposition.

Next, a hole injection layer 13a, a hole transport layer 13b, a light emitting layer 13c, an electron transport layer 13d, and an electron injection layer 13e are formed in this order on this, and the light emitting unit 13 is formed. As a film forming method of each of these layers, there are a spin coat method, a cast method, an ink jet method, a vapor deposition method, a printing method, etc., but from the point that a uniform film is easily obtained and pinholes are difficult to generate, etc. Vacuum deposition or spin coating is particularly preferred. Further, different film formation methods may be applied for each layer. When a vapor deposition method is employed for forming each of these layers, the vapor deposition conditions vary depending on the type of compound used, but generally a boat heating temperature of 50 to 450 ° C. and a degree of vacuum of 1 × 10 ⁻⁶ to 1 × 10 ⁻² Each condition is preferably selected as appropriate within the ranges of Pa, vapor deposition rate of 0.01 to 50 nm / second, substrate temperature of −50 to 300 ° C., and layer thickness of 0.1 to 5 μm.

After the light emitting unit 13 is formed, a second electrode 15 serving as a cathode is formed thereon by an appropriate film forming method such as a vapor deposition method or a sputtering method. At this time, the second electrode 15 is formed in a pattern in which a terminal portion is drawn from the upper side of the light emitting unit 13 to the periphery of the gas barrier film 20 while being insulated from the first electrode 12 by the light emitting unit 13.
Next, a sealing member 17 that covers at least the light emitting unit 13 is provided with the terminal portions of the extraction electrode 16 and the second electrode 15 in the organic EL element 10 exposed.

Thus, the desired organic EL element 10 can be formed on the gas barrier film 20. In the production of such an organic EL element 10, it is preferable to produce the light emitting unit 13 to the second electrode 15 consistently by a single evacuation. However, the resin base material 21 is taken out from the vacuum atmosphere in the middle and is different. A film forming method may be applied. At that time, it is necessary to consider that the work is performed in a dry inert gas atmosphere.

When a DC voltage is applied to the organic EL element 10 thus obtained, the first electrode 12 serving as an anode has a positive polarity and the second electrode 15 serving as a cathode has a negative polarity. Luminescence can be observed when about 40 V is applied. An alternating voltage may be applied. The alternating current waveform to be applied may be arbitrary.

[Effect of organic EL element]
The organic EL element 10 described above has an internal light extraction layer composed of the light scattering layer 14 and the smoothing layer 11 on the gas barrier film 20. Further, the gas barrier film 20 includes a gas barrier layer 22 including a silicon-containing layer 23 and a metal-containing layer 24. The gas barrier layer 22 can prevent impurities from entering from the resin base material 21 side. For this reason, the reliability and storability of the organic EL element 10 can be improved.
In addition, by providing the light scattering layer 14 and the smoothing layer 11 on the gas barrier film 20, it is possible to configure a light emitting device that achieves both improved light extraction efficiency and improved storage stability. .

[Uses of organic EL elements]
Since the organic EL elements having the above-described configurations are surface light emitters as described above, they can be used as various light emission sources. For example, lighting devices such as home lighting and interior lighting, backlights for clocks and liquid crystals, lighting for billboard advertisements, light sources for traffic lights, light sources for optical storage media, light sources for electrophotographic copying machines, light sources for optical communication processors, Examples include, but are not limited to, a light source of an optical sensor, and can be effectively used as a backlight of a liquid crystal display device combined with a color filter and a light source for illumination.

The organic EL element may be used as a kind of lamp such as an illumination or exposure light source, a projection device that projects an image, or a display device that directly recognizes a still image or a moving image. (Display) may be used. In this case, with the recent increase in the size of lighting devices and displays, the light emitting surface may be enlarged by so-called tiling, in which light emitting panels provided with organic EL elements are joined together in a plane.

The drive method when used as a display device for moving image reproduction may be either a simple matrix (passive matrix) method or an active matrix method. In addition, a color or full-color display device can be manufactured by using two or more organic EL elements having different emission colors.

[Lighting device]
An example of the use of the organic EL element is a lighting device.
The lighting device using the organic EL element may be designed such that each organic EL element having the above-described configuration has a resonator structure. Examples of the purpose of use of the organic EL element configured as a resonator structure include, but are not limited to, a light source of an optical storage medium, a light source of an electrophotographic copying machine, a light source of an optical communication processor, a light source of an optical sensor, and the like. . Moreover, you may use for the said use by making a laser oscillation.

Note that the material used for the organic EL element can be applied to an organic EL element that emits substantially white light (also referred to as a white organic EL element). For example, a plurality of light emitting materials can simultaneously emit a plurality of light emission colors to obtain white light emission by color mixing. As a combination of a plurality of emission colors, those containing the three emission maximum wavelengths of the three primary colors of red, green and blue may be used, or two emission using the complementary colors such as blue and yellow, blue green and orange, etc. It may contain a maximum wavelength.

In addition, a combination of light emitting materials for obtaining a plurality of emission colors is a combination of a plurality of phosphorescent or fluorescent materials, a light emitting material that emits fluorescence or phosphorescence, and excitation of light from the light emitting materials. Any combination with a pigment material that emits light as light may be used, but in a white organic EL element, a combination of a plurality of light-emitting dopants may be used.

Such a white organic EL element is different from a configuration in which organic EL elements emitting each color are individually arranged in parallel to obtain white light emission, and the organic EL element itself emits white light. For this reason, a mask is not required for film formation of most layers constituting the element, and deposition can be performed on one side by vapor deposition, casting, spin coating, ink jet, printing, etc., and productivity is also improved. To do.

Moreover, there is no restriction | limiting in particular as a light emitting material used for the light emitting layer of such a white organic EL element, For example, if it is a backlight in a liquid crystal display element, it will fit in the wavelength range corresponding to CF (color filter) characteristic. As described above, any one of the above-described metal complexes and known light-emitting materials may be selected and combined to be whitened.
If the white organic EL element demonstrated above is used, it is possible to produce the illuminating device which produces substantially white light emission.

Hereinafter, the present invention will be specifically described with reference to examples, but the present invention is not limited thereto. In addition, although the display of "%" is used in an Example, unless otherwise indicated, "mass%" is represented.

<Production of Gas Barrier Film of Sample 101 and Organic EL Element>
[Production of gas barrier film]
As a resin substrate, a 100 μm thick polyethylene terephthalate film (Lumirror (registered trademark) (U48), manufactured by Toray Industries, Inc.) with easy adhesion treatment on both sides was prepared. And the clear hard-coat layer which has an antiblock function of thickness 0.5 micrometer was formed in the surface on the opposite side to the surface which forms the silicon-containing layer of this resin base material. That is, a UV curable resin (manufactured by Aika Kogyo Co., Ltd., product number: Z731L) was applied to a dry film thickness of 0.5 μm, dried at 80 ° C., and then using a high-pressure mercury lamp in the air. Curing was performed under the condition of an irradiation energy amount of 0.5 J / cm ² .

Next, a clear hard coat layer having a thickness of 2 μm was formed on the surface of the resin base on the side where the silicon-containing layer is to be formed as follows. A UV curable resin OPSTAR (registered trademark) Z7527 manufactured by JSR Corporation was applied to a dry film thickness of 2 μm, dried at 80 ° C., and then irradiated with a high-pressure mercury lamp in air. Curing was performed under the condition of 0.5 J / cm ² . In this way, a resin base material with a hard coat layer was obtained. Hereinafter, in Examples and Comparative Examples, this resin substrate with a hard coat layer is simply referred to as a resin substrate.

As a silicon-containing compound, a dibutyl ether solution containing 20% by mass of perhydropolysilazane (manufactured by AZ Electronic Materials Co., Ltd., NN120-20) and an amine catalyst (N, N, N ′, N′-tetramethyl-1,6) -Dihydrohexane (TMDAH))-containing perhydropolysilazane 20% by mass dibutyl ether solution (manufactured by AZ Electronic Materials Co., Ltd., NAX120-20) was mixed at a ratio of 4: 1 (mass ratio) and further dried. A coating solution was prepared by appropriately diluting with dibutyl ether for film thickness adjustment.

Next, the coating solution was applied onto the resin substrate by spin coating so that the dry film thickness was 150 nm, and dried at 80 ° C. for 2 minutes. Next, with respect to the dried coating film, the shortest distance between the vacuum ultraviolet irradiation apparatus (external layer surface of the sample and the excimer lamp tube surface) having a Xe excimer lamp (excimer lamp light intensity: 130 mW / cm ² ) with a wavelength of 172 nm is used. 3 mm), and a vacuum ultraviolet ray irradiation treatment was performed with a vacuum ultraviolet ray irradiation energy amount (irradiation amount) of 2.5 J / cm ² . At this time, the irradiation atmosphere was replaced with nitrogen, and the oxygen concentration was set to 0.1% by volume. The stage temperature for installing the sample was set to 80 ° C.

The energy applied to the surface of the sample coating layer in the vacuum ultraviolet irradiation process was measured using a 172 nm sensor head using a UV integrating photometer: C8026 / H8025 UV POWER METER manufactured by Hamamatsu Photonics. At the time of measurement, the sensor head was installed at the center of the sample stage of the vacuum ultraviolet irradiation apparatus so that the shortest distance between the Xe excimer lamp tube surface and the measurement surface of the sensor head was 3 mm, and the atmosphere in the apparatus chamber was Nitrogen and oxygen were supplied so as to have the same oxygen concentration as in the vacuum ultraviolet irradiation step, and the measurement was performed by moving the sample stage at a speed of 0.5 m / min. Prior to the measurement, in order to stabilize the illuminance of the Xe excimer lamp, an aging time of 10 minutes was provided after the Xe excimer lamp was turned on, and then the sample stage was moved to start the measurement. Based on the irradiation energy obtained by this measurement, the moving speed of the sample stage was adjusted so that the above-mentioned irradiation energy was obtained. The vacuum ultraviolet irradiation was performed after aging for 10 minutes.

Next, the resin base material formed up to the silicon-containing layer was stored for 24 hours in an environment of 20 ° C. and a relative humidity of 50% RH. Thereafter, a metal-containing layer was formed on the silicon-containing layer using a magnetron sputtering apparatus and using the following target and film formation conditions.

A film was formed by DC sputtering using an oxygen-deficient Nb ₂ O ₅ target as a target and Ar and O _{2 as} process gases. The conditions of the composition were determined by adjusting the oxygen partial pressure in advance by film formation using a glass substrate, and the conditions were found such that the composition near the depth of 10 nm from the surface layer was Nb ₂ O ₃ . By applying these conditions, a film was formed with a thickness of 15 nm.
Through the above steps, a gas barrier film of Sample 101 was produced.

[Measurement of composition in region A]
The XPS measurement was performed on the gas barrier film of Sample 101 under the conditions described below. The results are shown in Table 2 below. As shown in Table 2 below, it was confirmed that the region A was formed.

(XPS composition analysis conditions)
・ Equipment: ULVAC-PHI QUANTERASXM
・ X-ray source: Monochromatic Al-Kα
・ Sputtering ion: Ar (2 keV)
Depth profile: after sputtering equivalent to 2.5 nm in terms of SiO ₂ , measurement was repeated to obtain a depth profile for every 2.5 nm in the depth direction of SiO ₂ .Quantification: obtained by obtaining the background by the Shirley method Quantification was performed from the peak area using the relative sensitivity coefficient method. For data processing, MultiPak manufactured by ULVAC-PHI was used.

[Production of light scattering layer]
Next, a light scattering layer was produced on the produced gas barrier film by the following method.
First, the solid content ratio of TiO ₂ particles having a refractive index of 2.4 and an average particle diameter of 0.25 μm (JR600A, manufactured by Taca Co., Ltd.) and a resin solution (ED230AL (organic-inorganic hybrid resin) manufactured by APM) was set to 40. The solid content concentration in propylene glycol monomethyl ether (PGME) was adjusted to 15% by mass. Then, 0.4 mass% additive (Disperbyk-2096 manufactured by Big Chemie Japan Co., Ltd.) was added to the solid content (effective mass component), and the formulation was designed at a ratio of 10 ml.

Specifically, the the TiO ₂ particles and a solvent and additives were mixed with 10% by weight ratio with respect to TiO ₂ particles, while cooling at room temperature (25 ° C.), an ultrasonic dispersing machine (manufactured by SMT Co. UH- 50) was dispersed for 10 minutes under the standard conditions of a microchip step (MS-3, 3 mmφ manufactured by SMT Co., Ltd.) to prepare a TiO ₂ dispersion.
Next, while stirring the TiO ₂ dispersion at 100 rpm, the resin solution was mixed and added little by little. After the addition was completed, the stirring speed was increased to 500 rpm, and the mixture was mixed for 10 minutes, and then a hydrophobic PVDF 0.45 μm filter (Whatman) To obtain the desired coating solution for light scattering layer.

The prepared coating solution for the light scattering layer is applied onto the gas barrier film by the ink jet coating method, and then simply dried (80 ° C., 2 minutes). Further, the output condition is that the substrate temperature is less than 80 ° C. by wavelength control IR. The drying process was performed for 5 minutes.

Next, the curing reaction was accelerated under the following modification treatment conditions to obtain a light scattering layer having a layer thickness of 0.3 μm.
(Modification equipment)
Excimer irradiation equipment MODEL: MEIRH-M-1-200-222-H-KM-G, wavelength 222 nm, lamp filled gas KrCl
(Reforming treatment conditions)
Excimer light intensity 8J / cm ² (222nm)
Stage heating temperature 60 ℃
Oxygen concentration in the irradiation device

[Production of smoothing layer]
As a coating solution for the smoothing layer, a high refractive index UV curable resin (manufactured by Toyo Ink Co., Ltd., Rio Duras TYT82-01, nanosol particles: TiO ₂ ), propylene glycol monomethyl ether (PGME) and 2-methyl-2 The formulation was designed in a ratio of 10 ml so that the solid content concentration in an organic solvent having a solvent ratio of 90% by mass / 10% by mass with 1,4-pentanediol (PD) was 12% by mass.

Specifically, the high refractive index UV curable resin and the solvent are mixed, mixed at 500 rpm for 1 minute, and then filtered through a hydrophobic PVDF 0.2 μm filter (manufactured by Whatman) for the intended smoothing layer. A coating solution was obtained.
After applying the coating solution on the light scattering layer by the inkjet coating method, it is simply dried (80 ° C., 2 minutes), and further subjected to a drying treatment for 5 minutes under an output condition with a substrate temperature of less than 80 ° C. by wavelength control IR. Executed.

Next, the curing reaction was promoted under the following modification treatment conditions, a smoothing layer having a layer thickness of 0.5 μm was formed, and an internal light extraction layer having a two-layer structure of a light scattering layer and a smoothing layer was produced.

(Modification equipment)
Excimer irradiation equipment MODEL: MEIRH-M-1-200-222-H-KM-G, wavelength 222 nm, lamp filled gas KrCl
(Reforming treatment conditions)
Excimer light intensity 8J / cm ² (222nm)
Stage heating temperature 60 ℃
Oxygen concentration in the irradiation device

[Production of first electrode]
The resin base material on which the internal light extraction layer was formed was fixed to a base material holder of a commercially available vacuum deposition apparatus. 46 was put in a resistance heating boat made of tantalum, and the substrate holder and the heating boat were attached to the first vacuum chamber of the vacuum deposition apparatus. Moreover, silver (Ag) was put into the resistance heating boat made from tungsten, and it attached in the 2nd vacuum chamber.

In this state, first, the first vacuum chamber was depressurized to 4 × 10 ⁻⁴ Pa, and then the following exemplified compound No. The heating boat containing 46 was energized and heated, and the following exemplary compound No. 1 having a layer thickness of 25 nm was formed on the substrate (smoothing layer) within a deposition rate range of 0.1 to 0.2 nm / second. An underlayer consisting of 46 was provided.

Next, the resin base material formed up to the underlayer is transferred to the second vacuum chamber while being vacuumed, and after the pressure of the second vacuum chamber is reduced to 4 × 10 ⁻⁴ Pa, the heating boat containing silver is energized and heated. Then, an electrode layer made of silver having a layer thickness of 8 nm was formed on the underlayer at a deposition rate of 0.1 to 0.2 nm / second to produce a first electrode.

[Production of light emitting unit]
The resin base material on which the internal light extraction layer and the first electrode were formed was overlapped with a mask having an opening with a width of 30 mm × 30 mm at the center and fixed to a substrate holder of a commercially available vacuum deposition apparatus. Moreover, each material which comprises a light emission unit was filled in each heating boat in a vacuum evaporation system in the optimal quantity for formation of each layer. In addition, the heating boat used what was produced with the resistance heating material made from tungsten.

Next, the inside of the vapor deposition chamber of the vacuum vapor deposition apparatus was depressurized to a vacuum degree of 4 × 10 ⁻⁴ Pa, and each layer was formed as follows by sequentially energizing and heating the heating boat containing each material.
First, a hole-injecting hole transporting material serving as both a hole-injecting layer and a hole-transporting layer made of α-NPD is heated by energizing a heating boat containing α-NPD represented by the following structural formula as a hole-transporting injecting material. A layer was formed on the first electrode. At this time, the deposition rate was 0.1 to 0.2 nm / second, and the layer thickness was 140 nm.

Next, each of the heating boat containing the host material H4 represented by the following structural formula and the heating boat containing the phosphorescent compound Ir-4 represented by the following structural formula were energized independently, respectively. A light emitting layer composed of the photoluminescent compound Ir-4 was formed on the hole transport injection layer. At this time, the energization of the heating boat was adjusted so that the deposition rate was the host material H4: phosphorescent compound Ir-4 = 100: 6. The layer thickness was 30 nm.
Next, a hole-blocking layer made of BAlq was formed on the light-emitting layer by heating a heated boat containing BAlq represented by the following structural formula as a hole-blocking material. At this time, the deposition rate was 0.1 to 0.2 nm / second, and the layer thickness was 10 nm.

Thereafter, a heating boat containing the following exemplary compound 10 and a heating boat containing potassium fluoride were energized independently, and an electron transport layer composed of the exemplary compound 10 and potassium fluoride was placed on the hole blocking layer. Formed. At this time, the energization of the heating boat was adjusted so that the vapor deposition rate was 10: potassium fluoride = 75: 25. The layer thickness was 30 nm.
Next, a heating boat containing potassium fluoride as an electron injection material was energized and heated to form an electron injection layer made of potassium fluoride on the electron transport layer. At this time, the deposition rate was 0.01 to 0.02 nm / second, and the layer thickness was 1 nm.

[Preparation of second electrode to sealing]
The resin base material formed up to the light emitting unit was transferred to a second vacuum tank equipped with a tungsten resistance heating boat containing aluminum (Al) while maintaining a vacuum state. And it overlapped and fixed to the mask with the opening part of width 20mm * 20mm arrange | positioned so that it may be orthogonal to an anode. Next, a reflective second electrode made of Al having a thickness of 100 nm was formed as a cathode at a film formation rate of 0.3 to 0.5 nm / second in the processing chamber.

Next, a thermosetting liquid adhesive (epoxy resin) having a thickness of 25 μm was formed as a sealing resin layer on one surface of a sealing member having the same configuration as the gas barrier film of the prepared sample 101. And the sealing member which provided this sealing resin layer was piled up on the sample in which even the 2nd electrode was formed. At this time, the sealing resin layer forming surface of the sealing member was continuously superimposed on the gas barrier film side of the organic EL element so that the end portions of the extraction portions of the first electrode and the second electrode were exposed. .

Next, the sample to which the sealing member was bonded was placed in a decompression device, and pressed at 90 ° C. under a decompression condition of 0.1 MPa and held for 5 minutes. Subsequently, the sample was returned to the atmospheric pressure environment and further heated at 90 ° C. for 30 minutes to cure the adhesive.

The sealing process is performed under atmospheric pressure and in a nitrogen atmosphere with a moisture content of 1 ppm or less in accordance with JIS B 9920. The measured cleanliness is class 100, the dew point temperature is −80 ° C. or less, and the oxygen concentration is 0.8 ppm or less. At atmospheric pressure. In addition, the description regarding formation of the extraction part etc. from the 1st electrode and the 2nd electrode is omitted.

<Production of Gas Barrier Film and Organic EL Element of Samples 102 to 107>
Gas barrier films and organic EL elements of Samples 102 to 107 were prepared using the same method as Sample 101 described above, except that the composition of region A was made to have the configuration shown in Table 2 below. The nitrogen atom composition ratio (N), the metal atom composition ratio (M), and the silicon atom composition ratio (Si) when the silicon atom composition ratio (Si) in the region A of the gas barrier film of each sample is 100 are set to 100. Table 2 shows the oxygen atom composition ratio (O).

<Production of Gas Barrier Film of Sample 108 and Organic EL Element>
A gas barrier film of Sample 108 and an organic EL element were produced using the same method as Sample 101 described above, except that the metal-containing layer was not formed in the production of the gas barrier layer. In the gas barrier film of sample 108 and the organic EL element, the gas barrier layer is constituted only by the silicon-containing layer. Nitrogen atom composition ratio (N), metal atom composition ratio (M) when silicon atom composition ratio (Si) at the interface (smoothing layer side) of the silicon-containing layer of the gas barrier film of sample 108 is 100, silicon Table 2 shows the oxygen atomic composition ratio (O) when the atomic composition ratio (Si) is 100.

<Production of Gas Barrier Film of Sample 109 and Organic EL Element>
A gas barrier film of Sample 109 and an organic EL element were produced using the same method as Sample 101 described above, except that a metal-containing layer made of Co was formed by the following method. In region A of the gas barrier film of sample 109, the nitrogen atom composition ratio (N), the metal atom composition ratio (M), and the silicon atom composition ratio (Si) are 100 when the silicon atom composition ratio (Si) is 100. Table 2 shows the oxygen atom composition ratio (O).

[Production of metal-containing layer]
The resin base material formed up to the silicon-containing layer was stored for 24 hours in an environment of 20 ° C. and a relative humidity of 50% RH. Thereafter, a metal-containing layer was formed on the silicon-containing layer by DC sputtering using a Co target as a target and Ar and O _{2 as} process gases. The condition of the composition was determined in advance by adjusting the oxygen partial pressure by film formation using a glass substrate, and the condition was found that the composition in the vicinity of a depth of 10 nm from the surface layer becomes Co ₃ O ₄ . A film with a thickness of 15 nm was applied under these conditions to produce a gas barrier film of Sample 109.

<Evaluation methods>
The following evaluations were performed on the gas barrier films and organic EL elements of the produced samples 101 to 109. The evaluation results are shown in Table 2.

[Preservability: Ca method evaluation of gas barrier film]
A Ca method evaluation sample (type evaluated by permeation concentration) prepared by the following method was stored in an 85 ° C. and 85% RH environment, and the corrosion rate of Ca was observed at regular intervals. 1 hour, 5 hours, 10 hours, 20 hours, and thereafter, observation and transmission density measurement (average of 4 points) every 20 hours, and when the measured transmission density is less than 50% of the initial transmission density value Was used as an index of storability of the organic EL device.
5: 400 hours or more 4: 300 hours or more and less than 400 hours 3: 200 hours or more and less than 300 hours 2: 100 hours or more and less than 200 hours 1: 1: 100 hours or less

(Ca method evaluation sample)
In each of the samples 101 to 109, a gas barrier film with an internal light extraction layer was prepared in which the light scattering layer and the internal light extraction layer of the smoothing layer were formed on the gas barrier film. Then, for this gas barrier film with an internal light extraction layer, the surface of the smoothing layer and the gas barrier layer surface around the smoothing layer are UV-cleaned, and then a thermosetting sheet as a sealing resin layer on the gas barrier layer surface An adhesive (epoxy resin) was bonded at a thickness of 20 μm. This was punched out to a size of 50 mm × 50 mm, then placed in a glove box and dried for 24 hours.

Next, one side of a 50 mm × 50 mm non-alkali glass plate (thickness 0.7 mm) was UV cleaned. Ca was vapor-deposited by the size of 20 mm x 20 mm through the mask in the center of the glass plate using the vacuum vapor deposition apparatus made from an EILS technology. The thickness of Ca was 80 nm. Then, the Ca vapor-deposited glass plate was moved into the glove box, placed so that the sealing resin layer surface of the gas barrier film and the Ca vapor-deposited surface of the glass plate were in contact, and adhered by vacuum lamination. At this time, heating at 110 ° C. was performed. Further, the adhered sample was placed on a hot plate set at 110 ° C. with the glass plate facing down and cured for 30 minutes to produce a Ca method evaluation cell.

[Bending preservation test]
The organic EL elements of Samples 101 to 109 are stored for 500 hours in an environment of 85 ° C. and 85% RH in a state where the organic EL element forming surface is wound around a plastic roller having a curvature of 6 mmφ. did. Thereafter, a current of 1 mA / cm ² was applied to each organic EL element removed from the roller to emit light. Next, a part of the light emitting portion of the organic EL element was enlarged and photographed with a 100 × optical microscope (MS-804 manufactured by Moritex Co., Ltd., lens MP-ZE25-200). Next, the captured image was cut out in a 2 mm square, and the presence or absence of dark spots was observed for each image. From the observation results, the ratio of the dark spot generation area to the light emission area was determined, and the dark spot resistance was evaluated according to the following criteria.

5: Generation of dark spots is not recognized at all 4: Dark spot generation area is 0.1% or more and less than 1.0% 3: Dark spot generation area is 1.0% or more; Less than 0% 2: Dark spot generation area is 3.0% or more and less than 6.0% 1: Dark spot generation area is 6.0% or more

Table 2 shows the gas barrier films of the samples 101 to 109, the metal M contained in the metal-containing layer in the organic EL element, the composition of the region A, and the evaluation results.

As shown in Table 2, the samples 101 to 107 containing Nb, Ti, or Ta in the metal-containing layer are more storable and bent than the sample 108 having no metal-containing layer and the sample 109 containing Co. Good results were obtained for both storage stability.
In particular, when the metal-containing layer contains Nb and the composition of region A has a silicon atom composition ratio of 100, the nitrogen atom composition ratio exceeds 0 and is 60 or less, and the metal atom composition ratio is 20 or more and 300 or less, Further, the sample 103 having an oxygen atom composition ratio of 40 or more and 300 or less obtained the best results in both storage stability and folding storage stability.

Nb is contained in the metal-containing layer, and the composition of region A has a silicon atom composition ratio of 100, a nitrogen atom composition ratio exceeding 0 and 60 or less, and a metal atom composition ratio satisfying 20 or more and 300 or less. The sample 102 having an oxygen atom composition ratio of 40 or more and 300 or less when the silicon atom composition ratio was 100 was lower in both storage stability and folding storage stability than the sample 103.
In addition, when the composition of the region A is defined as 100 as the silicon atom composition ratio, the sample 104 does not satisfy any of the nitrogen atom composition ratio exceeding 0 and 60 or less, or the metal atom composition ratio of 20 or more and 300 or less. In addition, the sample 105 was lower in both storage stability and folding storage stability than the sample 103.
From this result, when the gas barrier layer has a silicon atom composition ratio of 100, the nitrogen atom composition ratio exceeds 0 and is 60 or less, the metal atom composition ratio is 20 or more and 300 or less, and the oxygen atom composition ratio is 40. By having the region A that satisfies the above 300 or less, the reliability of the organic EL element can be improved.

When the metal-containing layer contains Ta or Ti and the composition of the region A is defined as a silicon atom composition ratio of 100, the nitrogen atom composition ratio exceeds 0 and is 60 or less, and the metal atom composition ratio is 20 or more and 300. Hereinafter, the sample 106 and the sample 107 satisfying an oxygen atomic composition ratio of 40 or more and 300 or less obtained good results in both storage stability and folding storage stability.
From this result, even in metals other than Nb, the reliability of the organic EL element can be improved by having the region A in the gas barrier layer.

<Preparation of organic EL elements of samples 201 to 209>
In the organic EL elements of the samples 101 to 109 described above, the organic EL elements of samples 201 to 209 were manufactured using the same method except that the method for forming the smoothing layer was changed to the CVD film forming method shown below.

[Smoothing layer]
The gas barrier film on which the light scattering layer was formed was mounted on the lower electrode side of the chamber of a parallel plate type plasma CVD apparatus (manufactured by Anelva, PED-401). Next, the chamber of the plasma CVD apparatus was depressurized to an ultimate vacuum of 1.0 × 10 ⁻² Pa using an oil rotary pump and a turbo molecular pump. Thereafter, nitrogen gas (N ₂ ) was introduced from the raw material supply apparatus into the chamber at 30 sccm via the raw material supply nozzle. The pressure adjusting valve between the chamber and the vacuum pump was adjusted to adjust the pressure in the chamber to 20 Pa. Next, power having a frequency of 90 kHz (applied power: 200 W) is applied to the lower electrode, and between the lower electrode and the upper electrode (in the vicinity of the opening (gas inlet) of the raw material supply nozzle in the chamber), A glow discharge plasma was generated. The silicon nitride film of the substrate was subjected to nitrogen plasma treatment for 1 minute to form a smoothing layer made of silicon nitride and having a layer thickness of 90 nm.

<Evaluation methods>
The organic EL elements of the produced samples 201 to 209 were evaluated for storage stability by the above-described Ca method evaluation and evaluation by bending storage stability test.

Table 3 shows the metal M contained in the metal-containing layer in the organic EL elements of the samples 201 to 209, the composition of the region A, and the evaluation results.

As shown in Table 3, samples 201 to 209 in which silicon nitride is formed using a plasma CVD method as the smoothing layer have both improved storage stability and folding storage stability compared to the above samples 101 to 109. ing. From this result, it can be seen that, as an organic EL element, it is preferable to provide a smoothing layer formed by a dry process rather than a smoothing layer formed by a wet process from the viewpoint of improving the storage stability. This is presumably because the layer formed by the dry process has a higher gas blocking effect (barrier property) than the layer formed by the wet process.

The present invention is not limited to the configuration described in the above embodiment, and various modifications and changes can be made without departing from the configuration of the present invention.

DESCRIPTION OF SYMBOLS 10 Organic EL element, 11 Smoothing layer, 12 1st electrode, 13 Light emission unit, 13a Hole injection layer, 13b Hole transport layer, 13c Light emission layer, 13d Electron transport layer, 13e Electron injection layer, 14 Light scattering layer, 15 Second electrode, 16 Extraction electrode, 17 Sealing member, 18 Auxiliary electrode, 19 Adhesive layer, 20 Gas barrier film, 21 Resin substrate, 22 Gas barrier layer, 23 Silicon-containing layer, 24 Metal-containing layer

Claims

A gas barrier film having a gas barrier layer formed on a resin substrate;
An internal light extraction layer comprising a light scattering layer provided on the gas barrier film, and a smoothing layer provided on the light scattering layer;
A first electrode provided on the internal light extraction layer, a second electrode, and a light emitting unit sandwiched between the first electrode and the second electrode,
The gas barrier layer includes a metal-containing layer containing a compound of at least one metal selected from V, Nb, Ta, Ti, Zr, Hf, Mg, Y, and Al, and a silicon-containing material containing silicon and nitrogen An organic electroluminescence device having a layer.
In the atomic composition distribution profile obtained when XPS composition analysis is performed in the layer thickness direction, the gas barrier layer has a silicon atom composition ratio of 100 and a nitrogen atom composition ratio of more than 0 and 60 or less, and a metal A region having an atomic composition ratio of 20 or more and 300 or less;
The organic electroluminescent element according to claim 1, wherein the metal-containing layer and the silicon-containing layer are in contact via the region.
The organic electroluminescence device according to claim 2, wherein the oxygen atom composition ratio is 40 or more and 300 or less when the silicon atom composition ratio in the region is 100.
The organic electroluminescence device according to claim 1, wherein the metal contained in the metal-containing layer is Nb.
2. The smoothing layer is mainly composed of at least one selected from silicon oxide, silicon nitride, niobium oxide, and niobium nitride, and has a water vapor permeability of less than 0.1 g / (m 2 · 24h). The organic electroluminescent element of description.