JPWO2014091868A1 - Method for manufacturing organic electroluminescence device - Google Patents

Abstract

The subject of this invention is providing the manufacturing method of the organic EL element excellent in economical efficiency, dark spot tolerance, luminous efficiency (luminous luminance), and luminous lifetime. The method for producing an organic EL device of the present invention has a gas barrier layer and an organic layer unit, the gas barrier layer contains carbon, silicon and oxygen, the composition continuously changes in the layer thickness direction, and a carbon distribution curve. Has an extreme value, the difference between the maximum and minimum extreme values of the carbon atom ratio is 5 at% or more, and silicon is the second content in the region of 90% or more of the total layer thickness. From the formation of the organic layer containing the solvent having the highest boiling point to the formation of the cathode, the boiling point of the highest boiling solvent used for forming the organic layer is −10 ° C. or higher, the glass transition temperature of the film substrate The heat treatment is performed at a temperature of + 20 ° C. or less, or each time an organic layer is formed, the organic layer is successively heated at a boiling point of the solvent of −10 ° C. or higher and a glass transition temperature of the film substrate of + 20 ° C. or lower. And

Description

  The present invention relates to a method for producing an organic electroluminescence device comprising a gas barrier film having a gas barrier layer whose composition changes continuously in the layer thickness direction.

  In recent years, researches for practical application of organic electroluminescence elements (hereinafter also referred to as organic EL elements) have been actively conducted. Particularly, in recent years, in addition to demands for weight reduction and size increase, long-term reliability ( Glass that is heavy, easy to break, and difficult to increase in area as a base material to be used, including demands such as high durability, high degree of freedom in shape, and ability to display curved surfaces. There has been an increasing demand for organic electroluminescence elements having a flexible base material instead of the base material.

  From the viewpoint of imparting flexibility, a resin film, a metal foil, or the like can be used as a base material. However, the organic electroluminescence element itself is basically a characteristic that is weak against water, oxygen, etc. In the case of using a film, it is necessary to provide a gas barrier layer as a layer having a high gas barrier property on the resin film in order to block water and oxygen from entering.

  As such a gas barrier layer, a method of forming a thin film made of an inorganic oxide such as silicon oxide, silicon nitride, silicon oxynitride, or aluminum oxide on a resin film substrate has been proposed.

  For example, as a method of forming a gas barrier layer made of an inorganic oxide on a resin film substrate, for example, a physical vapor deposition method (hereinafter abbreviated as PVD) such as a vacuum deposition method, a sputtering method, or an ion plating method. And chemical vapor deposition methods (hereinafter abbreviated as CVD) such as reduced pressure chemical vapor deposition and plasma enhanced chemical vapor deposition.

  As a film having a high gas barrier property formed by using such a film forming method, for example, a film in which a ceramic inorganic barrier film and a polymer film are alternately laminated is disclosed (for example, see Patent Document 1). .) In addition, a film forming method is disclosed in which a gas barrier layer having a gradient composition is formed and the composition of the coating material is continuously changed in the thickness direction (see, for example, Patent Document 2).

  In addition, organic electrolysis using a gas barrier film containing a gas barrier layer containing silicon, oxygen, and carbon as a gas barrier layer, and having a gas barrier layer in which a silicon atom ratio, an oxygen atom ratio, and a carbon atom ratio in a layer thickness direction have a specific relationship. A luminescence element is disclosed (for example, refer to Patent Document 3).

  On the other hand, for the formation of an organic layer (also referred to as an organic compound layer, for example, a hole injection layer, a hole transport layer, a light emitting layer, a hole blocking layer, an electron transport layer, etc.) constituting the organic electroluminescence element. Various methods such as vapor deposition, sputtering, CVD, PVD, and wet coating using a solvent can be applied. Among these methods, the manufacturing process is simplified, the manufacturing cost is reduced, and the processing is performed. It is known that a wet coating method (hereinafter also referred to as a wet film-forming method) is advantageous from the viewpoints of improving the performance and adaptability to flexible large-area devices such as a backlight and an illumination light source.

  Examples of materials used for forming the organic electroluminescence element include low molecular weight materials and high molecular weight materials. Low molecular weight materials can be purified by sublimation and can be easily purified, and can be used as high-purity organic electroluminescent materials. As a result, they are extremely effective in improving the luminous efficiency and lifetime of organic EL devices. In contrast, polymer materials have the disadvantages of being difficult to purify with high purity and deteriorating their luminous efficiency and lifetime. Recently, wet film-forming methods using low molecular materials have been actively studied. ing.

  An important problem in the wet film formation method is removal of a solvent remaining in the formed coating film (hereinafter referred to as residual solvent) after coating and drying. The reason for this is that if the solvent finally remains in the organic layer, it may cause dark spots and cause deterioration of the device life and light emission efficiency, which is inferior to the characteristics of the organic EL device manufactured by the vapor deposition process. It has become one.

  As the method for removing the residual solvent, there are generally two methods, a vacuum drying method and a heat drying method. However, the vacuum drying method cannot be manufactured in the atmosphere, which is one of the merits of the wet film formation method. Therefore, it is necessary to increase the size of the manufacturing equipment, and there is a problem with production aptitude. Therefore, it is considered preferable to apply the heat drying method from the viewpoint of production suitability.

  In the case of applying the heat drying method to the removal of the residual solvent, in order to remove the residual solvent as much as possible, it is necessary to heat the formed coating film containing the residual solvent to a temperature not lower than the boiling point of the solvent. However, when an organic layer is applied on a resin film substrate having a gas barrier layer of the above-described technique, the resin film substrate that is formed, particularly thermoplastic, is obtained when heat treatment is performed at a certain temperature. As a result, there is a problem that the flatness of the base material is impaired due to damage to the heat shrinkage or deformation of the film base material, and as a result, the gas barrier layer formed on the resin film base material is broken or It has been found that cracks occur, and as a result, problems such as point spots such as dark spots occur.

  For the above problem, for example, by using a heat-resistant resin film such as a polyimide film or an aramid film as a base material, although it can withstand heat treatment at a certain high temperature, a high heat-resistant film is It is generally expensive, and even when an inexpensive resin film such as a polyethylene terephthalate film or a polyethylene naphthalate film is used as a base material, there is no deterioration in performance when the residual solvent is removed by applying the heating drying method as described above. There is a need for a method of manufacturing a luminescence element.

JP 2002-532850 A JP 2005-537963 A JP 2012-084306 A

  The present invention has been made in view of the above problems, and the problem to be solved is that it uses a transparent resin film substrate, is excellent in economic efficiency, suppresses the occurrence of dark spots, has luminous efficiency (luminous luminance) and luminous lifetime. It is providing the manufacturing method of the flexible organic electroluminescent element excellent in the.

  In order to solve the above-mentioned problems, the present inventor, in the process of examining the cause and the like, a gas barrier layer having a specific element distribution profile on the transparent resin film substrate, the constituent element composition of which continuously changes. When forming an organic layer unit composed of a plurality of organic layers thereon, the boiling point of the solvent contained in the coating liquid used for forming each organic layer and the glass transition temperature of the transparent resin film substrate are determined. The present inventors have found that the above problems can be solved by performing heat treatment within a heat treatment temperature range having a specific relationship, and have reached the present invention.

  That is, the said subject which concerns on this invention is solved by the following means.

1. It is composed of a gas barrier layer containing carbon atoms, silicon atoms and oxygen atoms on a transparent resin film substrate, an anode and a cathode, and a plurality of organic layers including at least a light emitting layer between the anode and the cathode. A method for producing an organic electroluminescent element having an organic layer unit comprising:
The gas barrier layer is based on the element distribution measurement in the depth direction by X-ray photoelectron spectroscopy, and the distance from the surface in the layer thickness direction of the gas barrier layer and the total amount of silicon atoms, oxygen atoms and carbon atoms (100 at. %), The ratio of the amount of silicon atoms (referred to as “silicon atom ratio (at%)”), the ratio of the amount of oxygen atoms (referred to as “oxygen atom ratio (at%)”), and the ratio of the amount of carbon atoms (Referred to as “carbon atom ratio (at%)”) A silicon distribution curve, an oxygen distribution curve and a carbon distribution curve satisfying the following conditions (1) to (3):
And after the organic layer unit forms the organic layer containing a solvent by apply | coating each organic layer coating liquid prepared by melt | dissolving the formation material of each organic layer in a solvent, it is until it forms the said cathode. In the process of
Forming the organic layer by batch heat treatment within the range of the heat treatment temperature defined by the following formula (a);
Or, within the range of the heat treatment temperature specified by the following formula (b), each time the organic layer is formed, it is formed by sequential heat treatment,
The manufacturing method of the organic electroluminescent element characterized by these.

  (1) In the gas barrier layer, the composition of each atom continuously changes in the layer thickness direction, and the carbon distribution curve has an extreme value.

  (2) The difference between the maximum extreme value and the minimum extreme value of the carbon atom ratio is 5 at% or more.

  (3) In a region of 90% or more of the total thickness of the gas barrier layer, the atomic ratio (at%) of each atom to the total amount (100 at%) of silicon atoms, oxygen atoms and carbon atoms is expressed by the following formula (A ) Or (B).

Formula (A): (carbon atom ratio) <(silicon atom ratio) <(oxygen atom ratio)
Formula (B): (oxygen atom ratio) <(silicon atom ratio) <(carbon atom ratio)
Formula (a): (The boiling point of the solvent having the highest boiling point among the solvents used for forming the organic layer −10 ° C.) ≦ (heat treatment temperature) ≦ (glass transition temperature (Tg) of the transparent resin film substrate + 20 ° C. )
Formula (b): (boiling point of the solvent constituting the coating solution for forming the organic layer −10 ° C.) ≦ (heat treatment temperature) ≦ (glass transition temperature (Tg) + 20 ° C. of the transparent resin film substrate)
2. The step of collectively heat-treating the organic layer within the range of the heat treatment temperature defined by the formula (a) is a step after forming the final organic layer and before forming the cathode. 2. A method for producing an organic electroluminescence element according to item 1, characterized in that

  3. The method for producing an organic electroluminescence element according to item 1 or 2, wherein the organic layer unit comprises at least a hole injection layer, a hole transport layer, a light emitting layer, and an electron transport layer.

  4). The organic light-emitting device according to any one of items 1 to 3, wherein the light-emitting layer contains a light-emitting host compound having a molecular weight of 2000 or less and a light-emitting dopant having a molecular weight of 2000 or less. Production method.

  5. The gas barrier layer is formed using a discharge plasma chemical vapor deposition apparatus that uses a source gas containing an organic silicon compound and oxygen gas to form a discharge space between film forming rollers having opposing magnetic fields. The manufacturing method of the organic electroluminescent element as described in any one of 1st term | claim to 4th term.

  6). The said transparent resin film base material is the polyethylene terephthalate film or polyethylene naphthalate film by which biaxial stretching was carried out, The manufacture of the organic electroluminescent element as described in any one of Claim 1-5 characterized by the above-mentioned. Method.

  By the above-mentioned means of the present invention, a transparent organic resin film substrate is used, a method for producing a flexible organic electroluminescence device that is excellent in economic efficiency, suppresses the occurrence of dark spots, and has excellent emission quantum efficiency (emission luminance) and emission lifetime. Can be provided.

  The technical reason why the effect of the present invention is obtained by the configuration of the present invention has not been clarified in detail, but is presumed as follows.

  That is, in the method for producing an organic electroluminescence element of the present invention, a gas barrier layer having a specific element distribution profile is formed on a transparent resin film substrate, and an organic layer composed of a plurality of organic layers is formed thereon. The boiling point-10 of the solvent having the highest boiling point among the solvents contained in the coating solution used for forming each organic layer of the hole injection layer, the hole transport layer, the light emitting layer, and the electron transport layer when forming the unit. Efficient drying can be performed by performing the heat treatment in a heating temperature range in which the temperature is set to the lower limit of the heat treatment temperature and the upper temperature is Tg + 20 ° C. or less of the transparent resin film substrate used. If the heat treatment temperature is in the temperature range of the boiling point of the solvent having the highest boiling point −10 ° C. or more, the amount of residual solvent in the formed organic layer can be reduced, and the emission quantum efficiency (emission luminance) by the remaining solvent can be reduced. In addition, it is possible to suppress the deterioration of the light emission lifetime and to suppress the generation of dark spots and the like when stored for a long period of time in a high temperature and high humidity environment. In addition, by performing heat treatment at a heat treatment temperature of Tg + 20 ° C. or less of the transparent resin film substrate used, the used solvent can be removed sufficiently, and the transparent resin film substrate expands and contracts by heat treatment. Even within this temperature range, the gas barrier layer having a specific element distribution profile formed on the transparent resin film substrate and having a composition continuously changing in the layer thickness direction is Since it can effectively absorb the stretching stress of the transparent resin film base material, it can effectively prevent the gas barrier layer from cracking and the like. Even when stored for a long period of time, the generation of dark spots due to the destruction or cracking of the gas barrier layer is suppressed, and it has excellent emission quantum efficiency (emission luminance) and emission lifetime It is assumed that it was possible to realize a method for manufacturing an organic electroluminescent device.

  Similarly to the above, each organic layer coating prepared by dissolving an organic layer unit in a solvent with an organic layer unit composed of a hole injection layer, a hole transport layer, a light emitting layer, and an electron transport layer. By sequentially applying the liquid, coating and forming the hole injection layer, the hole transport layer, the light emitting layer, and the electron transport layer, followed by heat treatment at the heat treatment temperature defined in (b) above. , Luminescence quantum efficiency (luminescence brightness), suppression of emission lifetime degradation, and even when stored for a long time under high temperature and high humidity environment, the occurrence of dark spots due to cracks in the gas barrier layer is suppressed, and light emission It is presumed that a manufacturing method of a flexible organic electroluminescence device excellent in quantum efficiency (light emission luminance) and light emission lifetime could be realized.

Sectional drawing which shows an example of a structure of the organic electroluminescent element which concerns on this invention Schematic which shows an example of the manufacturing process of the gas barrier film which equipped with the discharge plasma CVD apparatus which has an opposing film-forming roller provided with the magnetic field generator applicable to formation of the gas barrier layer based on this invention. The graph which shows an example of the silicon distribution curve of the gas barrier layer which concerns on this invention, an oxygen distribution curve, and a carbon distribution curve The graph which shows an example of the silicon distribution curve, oxygen distribution curve, and carbon distribution curve of the gas barrier layer of a comparative example

The method for producing an organic electroluminescence device of the present invention comprises a gas barrier layer containing a carbon atom, a silicon atom and an oxygen atom, an anode and a cathode, and at least between the anode and the cathode on a transparent resin film substrate. A method for producing an organic electroluminescence device having an organic layer unit composed of a plurality of organic layers including a light emitting layer,
The gas barrier layer is based on the element distribution measurement in the depth direction by X-ray photoelectron spectroscopy, and the distance from the surface in the layer thickness direction of the gas barrier layer and the total amount of silicon atoms, oxygen atoms and carbon atoms (100 at. %), The silicon distribution curve, the oxygen distribution curve, and the carbon distribution curve showing the relationship between the ratio of the amount of silicon atoms, the ratio of the amount of oxygen atoms, and the ratio of the amount of carbon atoms are the above conditions (1) to (3 )The filling,
And after the organic layer unit forms the organic layer containing a solvent by apply | coating each organic layer coating liquid prepared by melt | dissolving the formation material of each organic layer in a solvent, it is until it forms the said cathode. In the step, the organic layer is formed by batch heat treatment within the range of the heat treatment temperature defined by the formula (a), that is, among the solvents contained in the coating liquid used for forming each organic layer, The organic layer is subjected to a batch heat treatment within the temperature range that is the upper limit of the heat treatment temperature at a boiling point of a solvent having a high boiling point of −10 ° C. or higher and Tg + 20 ° C. or lower of the transparent resin film substrate used. Forming an organic layer unit, or forming an organic layer unit by sequentially heating each time each organic layer is formed within the range of the heat treatment temperature defined by the formula (b). Features. This feature is a technical feature common to or corresponding to the inventions according to claims 1 to 6.

  In the present invention, in any of the methods described above, the upper limit of the heat treatment temperature is the transparent used, through the formation of all organic layers of the hole injection layer, the hole transport layer, the light emitting layer, and the electron transport layer. It is less than Tg + 20 degreeC of a resin film base material.

  As an embodiment of the present invention, from the viewpoint of manifesting the effect of the present invention, the step of batch-heating the organic layer within the range of the heat treatment temperature defined by the formula (a) forms the final organic layer. It is preferable from the viewpoint of obtaining a more excellent light emission quantum efficiency (light emission luminance) and light emission lifetime after being performed and before forming the cathode.

  The organic layer unit is preferably composed of at least a hole injection layer, a hole transport layer, a light emitting layer, and an electron transport layer.

  In addition, it is preferable that the light emitting layer contains a light emitting host compound having a molecular weight of 2000 or less and a light emitting dopant having a molecular weight of 2000 or less from the viewpoint of obtaining a more excellent light emission quantum efficiency (light emission luminance) and light emission lifetime.

  Further, the gas barrier layer is disposed at opposing positions using a source gas containing an organosilicon compound and an oxygen gas, and a discharge plasma chemical vapor forming a discharge space between film forming rollers having a magnetic field therein. It is preferable to use a phase growth apparatus from the viewpoint that the composition is precisely controlled and a gas barrier layer having a desired element profile in the layer thickness direction can be stably formed.

  It is preferable to use a biaxially stretched polyethylene terephthalate film or polyethylene naphthalate film as the transparent resin film substrate from the viewpoint of being excellent in economy and imparting flexibility.

The “gas barrier property” as used in the present invention is a water vapor permeability (temperature: 60 ± 0.5 ° C., relative humidity (RH): 90 ± 2%) measured by a method according to JIS K 7129-1992. ) Is 3 × 10 ⁻³ g / m ² · 24 h or less, and the oxygen permeability measured by a method according to JIS K 7126-1987 is 1 × 10 ⁻³ ml / m ² · 24 h · atm or less. Means that.

  The term “transparent” as used in the present invention means that the total light transmittance in the visible light wavelength region measured by a method based on JIS K 7361-1: 1997 (Testing method for total light transmittance of resin transparent material) is 70. % Or more.

  Moreover, in this invention, the glass transition temperature Tg of a transparent resin film base material can be measured using the differential scanning calorimeter DSC220 by Seiko Electronic Industry Co., Ltd. according to JISK7121.

  Hereinafter, the present invention, its components, and modes and modes for carrying out the present invention will be described in detail. However, the present embodiment is not limited to the following contents, and does not depart from the gist of the present invention. It is possible to implement with any change. In the present invention, “to” is used to mean that the numerical values described before and after it are included as a lower limit value and an upper limit value.

<< Method for Manufacturing Organic Electroluminescent Element >>
The method for producing the organic electroluminescence element of the present invention is as follows.
1) forming a gas barrier layer containing carbon atoms, silicon atoms and oxygen atoms on a transparent resin film substrate;
2) forming a plurality of organic layers including at least a light emitting layer between the anode and the cathode and the anode and the cathode on the gas barrier layer;
have.

  The gas barrier layer according to the present invention is based on the element distribution measurement in the depth direction by X-ray photoelectron spectroscopy, the distance from the surface in the layer thickness direction of the gas barrier layer, and the total of silicon atoms, oxygen atoms and carbon atoms The ratio of the amount of silicon atoms to the amount (100 at%) (referred to as “silicon atom ratio (at%)”), the ratio of the amount of oxygen atoms (referred to as “oxygen atomic ratio (at%)”), and the number of carbon atoms A silicon distribution curve, an oxygen distribution curve, and a carbon distribution curve showing a relationship with a ratio of amounts (referred to as “carbon atom ratio (at%)”) are formed in a configuration satisfying the following conditions (1) to (3). It is characterized by that.

That is,
(1) In the gas barrier layer, the composition of each atom continuously changes in the layer thickness direction, and the carbon distribution curve has an extreme value.

  (2) The difference between the maximum extreme value and the minimum extreme value of the carbon atom ratio is 5 at% or more.

  (3) In a region of 90% or more of the total thickness of the gas barrier layer, the atomic ratio (at%) of each atom to the total amount (100 at%) of silicon atoms, oxygen atoms and carbon atoms is expressed by the following formula (A ) Or (B).

Formula (A): (carbon atom ratio) <(silicon atom ratio) <(oxygen atom ratio)
Formula (B): (oxygen atom ratio) <(silicon atom ratio) <(carbon atom ratio)
As a method of forming a gas barrier layer having the above-defined configuration, for example, the method described in JP 2012-84306 A or WO 2012/046767, which is Patent Document 3, can be referred to. .

Further, in the present invention, the organic layer unit forms the cathode after forming the organic layer containing the solvent by applying each organic layer coating solution prepared by dissolving each organic layer forming material in the solvent. In the process until
The organic layer unit is formed by batch heating the organic layer within the range of the heat treatment temperature defined by the following formula (a),
Or, each time the organic layer unit is formed within the range of the heat treatment temperature defined by the following formula (b), each organic layer is formed by sequential heat treatment,
It is characterized by.

Formula (a): (The boiling point of the solvent having the highest boiling point among the solvents used for forming the organic layer −10 ° C.) ≦ (heat treatment temperature) ≦ (glass transition temperature (Tg) of the transparent resin film substrate + 20 ° C. )
Formula (b): (boiling point of the solvent constituting the coating solution for forming the organic layer −10 ° C.) ≦ (heat treatment temperature) ≦ (glass transition temperature (Tg) + 20 ° C. of the transparent resin film substrate)
<< Structure of organic electroluminescence element >>
In FIG. 1, an example of a structure of the organic electroluminescent element which concerns on this invention is shown.

  In FIG. 1, an organic EL element (EL) includes a transparent resin film substrate 1 and a gas barrier layer according to the present invention having a specific element profile in the layer thickness direction on one surface of the transparent resin film substrate 1. 2 is formed to constitute the gas barrier film F. On the gas barrier layer 2 according to the present invention, for example, the first electrode 3 is provided as an anode. And on the 1st electrode 3, it has the organic layer unit 4 comprised from a positive hole injection layer, a positive hole transport layer, a light emitting layer, and an electron carrying layer, for example, on the organic layer unit 4, for example, a cathode As a result, the second electrode 5 is arranged. Furthermore, the sealing member 6 is disposed in a state of covering the second electrode 5, and the organic EL element (EL) is sealed by the sealing member 6.

  In the organic EL element (EL) illustrated in FIG. 1, an organic layer composed of, for example, a hole injection layer, a hole transport layer, a light emitting layer, and an electron transport layer by the first electrode 3 and the second electrode 5 facing each other. The unit 4 is sandwiched. The organic EL element (EL) is shown as a so-called bottom emission type configuration example in which light from the organic layer unit 4 is extracted from the transparent resin film substrate 1 side.

[Transparent resin film substrate]
Examples of the resin material constituting the transparent resin film substrate 1 (hereinafter, also simply referred to as a resin substrate, a film substrate, or a substrate) include polyethylene terephthalate (abbreviation: PET), polyethylene naphthalate (abbreviation: abbreviation: PEN), polyester resins such as modified polyester, polyethylene (abbreviation: PE), polypropylene (abbreviation: PP), polyolefins such as polystyrene and cyclic olefin resin, vinyl resins such as polyvinyl chloride and polyvinylidene chloride, poly Ether ether ketone (abbreviation: PEEK), polysulfone (abbreviation: PSF), polyethersulfone (abbreviation: PES), polycarbonate (abbreviation: PC), polyamide, polyimide, acrylic resin, triacetyl cellulose (abbreviation: TAC), etc. Can be mentioned.

  Among them, from the viewpoint of transparency, heat resistance, ease of handling, film strength and cost, biaxially stretched polyethylene terephthalate (PET), biaxially stretched polyethylene naphthalate (PEN), polyethersulfone (PES), polycarbonate (PC And biaxially stretched polyethylene terephthalate (PET) or biaxially stretched polyethylene naphthalate (PEN).

  The film thickness of the transparent resin film substrate according to the present invention is preferably in the range of 1 to 1000 μm, and more preferably in the range of 10 to 100 μm.

[Substrate surface treatment]
From the viewpoint of improving the adhesion between the base material and the gas barrier layer formed thereon, the transparent base material can be subjected to a surface treatment or an easy-adhesion layer. Conventionally known techniques can be applied to the surface treatment and the easy adhesion layer. Examples of the surface treatment include surface activation treatment such as corona discharge treatment, flame treatment, ultraviolet treatment, high frequency treatment, glow discharge treatment, active plasma treatment, and laser treatment.

  Examples of the material for forming the easy adhesion layer include resins such as polyester, polyamide, polyurethane, vinyl copolymer, butadiene copolymer, acrylic copolymer, vinylidene copolymer, and epoxy copolymer. Ingredients can be mentioned. The easy adhesion layer may be a single layer, but may be composed of two or more layers in order to improve adhesion.

[Gas barrier layer]
The gas barrier layer according to the present invention is formed on at least one surface side of the transparent resin film substrate.

  The gas barrier layer according to the present invention is based on the element distribution measurement in the depth direction by X-ray photoelectron spectroscopy, the distance from the surface in the layer thickness direction of the gas barrier layer, and the total of silicon atoms, oxygen atoms and carbon atoms The ratio of the amount of silicon atoms to the amount (100 at%) (referred to as “silicon atom ratio (at%)”), the ratio of the amount of oxygen atoms (referred to as “oxygen atomic ratio (at%)”), and the number of carbon atoms The silicon distribution curve, oxygen distribution curve, and carbon distribution curve showing the relationship with the ratio of amounts (referred to as “carbon atom ratio (at%)”) satisfy the following conditions (1) to (3): .

  (1) The composition of the gas barrier layer continuously changes in the layer thickness direction, and the carbon distribution curve has at least one extreme value.

  (2) The difference between the maximum extreme value and the minimum extreme value of the carbon atom ratio is 5 at% or more.

  (3) In a region of 90% or more of the total thickness of the gas barrier layer, the atomic ratio (at%) of each atom to the total amount (100 at%) of silicon atoms, oxygen atoms and carbon atoms is expressed by the following formula (A ) Or (B).

Formula (A): (carbon atom ratio) <(silicon atom ratio) <(oxygen atom ratio)
Formula (B): (oxygen atom ratio) <(silicon atom ratio) <(carbon atom ratio)
In the present invention, at least one gas barrier layer containing silicon, oxygen and carbon and satisfying all of the conditions (1) to (3) defined as the silicon distribution curve, oxygen distribution curve and carbon distribution curve is provided. Just do it. Moreover, on the resin film base material, you may have the other structural layer which does not satisfy | fill at least 1 conditions of said conditions (1)-(3) in the range which does not impair the objective effect of this invention. The gas barrier layer according to the present invention may further contain nitrogen or aluminum as a constituent element in addition to silicon, oxygen and carbon.

  When the gas barrier layer does not satisfy all of the above conditions (1) to (3) defined in the present invention, even if the heat treatment conditions defined in (a) above are cleared, the luminous efficiency and life are improved. It has been found that, when the solvent is heated under a temperature condition of boiling point −10 ° C. or higher in order to remove the adverse solvent, many dark spots are generated in the storage stability evaluation described later.

  In addition, even when the gas barrier layer satisfies all of the above conditions (1) to (3) defined in the present invention, heating is performed under a temperature condition of the glass transition temperature of the resin film substrate + 20 ° C or higher. When it is carried out, excessive stretching occurs in the resin film substrate, and the stress applied by the expansion and contraction of the resin film substrate causes a crack (also referred to as a crack) in the gas barrier layer. It was found that dark spots occurred frequently after storage for a long time in the environment.

  If the gas barrier layer according to the present invention satisfying all of the above conditions (1) to (3) defined in the present invention is a heat treatment temperature lower than the glass transition temperature of the resin film substrate + 20 ° C., the resin film substrate Even when some expansion and contraction of the gas occurs, the stress applied to the gas barrier layer can be efficiently relaxed, and as a result, it does not cause cracks, etc., and has good storage stability, and an organic layer coating formed thereon In this case, the temperature range that can be applied in the solvent removal step can be expanded.

  In the condition (3) according to the present invention, the region satisfying the formula (A) or the formula (B) defined in the present invention is 90% or more of the total thickness of the gas barrier layer, Preferably it is 95% or more, Most preferably, it is 100%.

  The gas barrier layer according to the present invention is characterized in that the carbon distribution curve has at least one extreme value in the condition (1). Furthermore, in the gas barrier layer according to the present invention, the carbon distribution curve preferably has two or more extreme values, and particularly preferably has three or more extreme values. In the case of having at least three extreme values, the distance in the layer thickness direction between adjacent extreme values of the carbon distribution curve is preferably 200 nm or less, and more preferably 100 nm or less.

  In addition, the extreme value as used in the field of this invention is the maximum value (convex pattern) or the minimum value (concave pattern) of the atomic ratio (at%) of the element with respect to the distance from a surface layer surface in the layer thickness direction of a gas barrier layer. Say.

  The maximum value as used in the present invention is a point where the atomic ratio value (at%) of an element changes from increase to decrease when the distance from the surface of the gas barrier layer is changed, and the element at that point The value of the atomic ratio of the element at a position where the distance from the surface of the gas barrier layer in the layer thickness direction of the gas barrier layer from the point is further changed by 20 nm is reduced by 3 at% or more than the atomic ratio value (at%). It means a point.

  The minimum value in the present invention is a point where the atomic ratio value (at%) of an element changes from decrease to increase when the distance from the surface of the gas barrier layer is changed, and the element at that point The atomic ratio value of the element at a position where the distance from the surface of the gas barrier layer in the thickness direction of the gas barrier layer in the thickness direction of the gas barrier layer is further changed by 20 nm from the point is increased by 3 at% or more. The point to do.

  Further, in the gas barrier layer according to the present invention, as defined in the above condition (2), the difference between the maximum extreme value and the minimum extreme value of the carbon atom ratio in the carbon distribution curve is 5 at% or more. It is characterized by.

  In the gas barrier layer having such characteristics, the difference between the maximum extreme value and the minimum extreme value of the atomic ratio of carbon is preferably 6 at% or more, particularly 7 at% or more. preferable.

(Oxygen distribution curve, extreme value)
In the gas barrier layer according to the present invention, the oxygen distribution curve of the gas barrier layer preferably has at least one extreme value, more preferably has at least two extreme values, and has at least three extreme values. Is particularly preferred. When the oxygen distribution curve has an extreme value, the dark spot resistance in the storage stability evaluation described later tends to be improved. In the case of having at least three extreme values as described above, the gas barrier in the thickness direction of the gas barrier layer at one extreme value and the other extreme value adjacent to the extreme value of the oxygen distribution curve. The absolute value of the difference in distance from the surface of the layer is preferably 200 nm or less, and more preferably 100 nm or less.

(Difference between maximum extreme value and minimum extreme value in oxygen distribution curve and silicon distribution curve)
In the gas barrier layer according to the present invention, the difference between the maximum extreme value and the minimum extreme value of the atomic ratio (at%) of oxygen in the oxygen distribution curve of the gas barrier layer may be 5 at% or more. Preferably, it is 6 at% or more, more preferably 7 at% or more. When the difference between the maximum value and the minimum value is 5 at% or more, the dark spot resistance in the storage stability evaluation described later tends to be improved.

  In the present invention, in the silicon distribution curve of the gas barrier layer, the difference between the maximum extreme value and the minimum extreme value of the atomic ratio of silicon is preferably less than 5 at%, more preferably less than 4 at%. Preferably, it is particularly preferably less than 3 at%. If the difference between the maximum extreme value and the minimum extreme value is less than 5 at%, the dark spot resistance in the storage stability evaluation described later tends to be improved.

(Difference between the maximum extreme value and the minimum extreme value in the oxygen-carbon distribution curve)
Further, in the gas barrier layer according to the present invention, the total amount of oxygen atoms and carbon atoms with respect to the distance from the surface in the layer thickness direction of the gas barrier layer and the total amount (100 at%) of silicon atoms, oxygen atoms and carbon atoms. In the oxygen-carbon distribution curve showing the relationship with the ratio (atomic ratio of oxygen and carbon, at%), the maximum extreme value and the minimum extreme value of the sum (at%) of the atomic ratio of oxygen and carbon in the oxygen-carbon distribution curve The difference in value is preferably less than 5 at%, more preferably less than 4 at%, and particularly preferably less than 3 at%. If the difference between the maximum extreme value and the minimum extreme value is less than 5 at%, the dark spot resistance in the storage stability evaluation described later tends to be improved.

(Creation of element distribution curve)
As described above, the silicon distribution curve, oxygen distribution curve, carbon distribution curve and oxygen-carbon distribution curve of the gas barrier layer according to the present invention are measured by X-ray photoelectron spectroscopy (XPS) and a rare gas such as argon. By using together with ion sputtering, it can be created by so-called XPS depth profile measurement in which the surface composition analysis is sequentially performed while exposing the inside of the sample. The element distribution curve obtained by such XPS depth profile measurement can be created, for example, with the vertical axis as the atomic ratio (unit: at%) of each element and the horizontal axis as the etching time (sputtering time). In the element distribution curve with the horizontal axis as the etching time in this way, the etching time generally correlates with the distance from the surface layer of the gas barrier layer in the layer thickness direction to the layer thickness direction. The “distance from the surface of the gas barrier layer in the thickness direction of the barrier layer” can be calculated from the relationship between the etching rate and the etching time employed in the XPS depth profile measurement.

In addition, as a sputtering method employed for such XPS depth profile measurement, a rare gas ion sputtering method using argon (Ar ⁺ ) as an etching ion species is employed, and the etching rate (etching rate) is 0.05 nm / It is preferable to set to sec (SiO ₂ thermal oxide film conversion value).

  In addition, the gas barrier layer according to the present invention has a uniform gas barrier layer with excellent gas barrier properties with no variation in characteristics in the entire surface area, and the gas barrier layer is in the film surface direction. In the (direction parallel to the surface of the gas barrier layer), the composition is preferably substantially uniform (uniform).

  In the gas barrier layer according to the present invention, that the composition is substantially uniform in the film surface direction means that the oxygen distribution curve at any two measurement points on the film surface of the gas barrier layer by XPS depth profile measurement, When the carbon distribution curve and the oxygen carbon distribution curve are created, the number of extreme values of the carbon distribution curve obtained at any two measurement locations is the same, and the carbon atoms in the respective carbon distribution curves It means that the difference between the maximum extreme value and the minimum extreme value of the ratio is the same or within 5 at%.

  Further, in the present invention, it is preferable that the carbon distribution curve changes substantially continuously in the layer thickness direction. In the present invention, the fact that the carbon distribution curve changes substantially continuously means that the carbon distribution curve does not include a portion where the atomic ratio of carbon changes discontinuously. Specifically, the distance (x, unit: nm) from the surface in the layer thickness direction of the gas barrier layer calculated from the etching rate and etching time, the atomic ratio of carbon (c, unit: at%), In the relationship, the condition represented by the following formula (F1) is satisfied.

Formula (F1): −1.0 ≦ (dc / dx) ≦ 1.0
In the present invention, it is necessary to provide at least one gas barrier layer satisfying all of the above conditions (1) to (3) on the transparent resin film substrate, but all of the above conditions (1) to (3) are required. A plurality of gas barrier layers may be provided. Furthermore, when two or more gas barrier layers having the above-described configuration defined in the present invention are provided, the constituent materials of the plurality of gas barrier layers may be the same or different. When two or more such gas barrier layers are provided, the gas barrier layer may be formed in two or more layers on one side of the transparent resin film substrate. Each may be formed on the surface side.

  In the region of 90% or more of the total thickness of the silicon distribution curve of the gas barrier layer, the oxygen distribution curve and the carbon distribution curve, the atomic ratio of silicon, the atomic ratio of oxygen and the atomic ratio of carbon satisfy the condition (3). When the condition represented by the formula (A) to be defined is satisfied, the atomic ratio (at%) of the silicon atom content to the total amount of silicon atoms, oxygen atoms and carbon atoms in the gas barrier layer according to the present invention Is preferably in the range of 25-45 at%, more preferably in the range of 30-40 at%. Further, the atomic ratio (at%) of the oxygen atom content to the total amount of silicon atoms, oxygen atoms and carbon atoms in the gas barrier layer according to the present invention is preferably in the range of 33 to 67 at%, More preferably, it is within the range of 45 to 67 at%. Furthermore, the atomic ratio (at%) of the carbon atom content to the total amount of silicon atoms, oxygen atoms and carbon atoms in the gas barrier layer according to the present invention is preferably in the range of 3 to 33 at%, More preferably, it is in the range of 3 to 25 at%.

  In the region of 90% or more of the total layer thickness of the silicon distribution curve, the oxygen distribution curve, and the carbon distribution curve of the gas barrier layer, the atomic ratio of silicon, the atomic ratio of oxygen, and the atomic ratio of carbon are the conditions (3 In the case where the condition represented by the formula (B) defined by (1) is satisfied, the atomic ratio of the content of silicon atoms to the total amount of silicon atoms, oxygen atoms and carbon atoms in the gas barrier layer according to the present invention (at %) Is preferably in the range of 25 to 45 at%, and more preferably in the range of 30 to 40 at%. The atomic ratio (at%) of the oxygen atom content to the total amount of silicon atoms, oxygen atoms and carbon atoms in the gas barrier layer according to the present invention is preferably in the range of 1 to 33 at%. More preferably, it is in the range of 10 to 27 at%. Further, the atomic ratio (at%) of the carbon atom content to the total amount of silicon atoms, oxygen atoms and carbon atoms in the gas barrier layer is preferably in the range of 33 to 66 at%, and preferably 40 to 57 at%. % Is more preferable.

  The layer thickness of the gas barrier layer is preferably in the range of 5 to 3000 nm, more preferably in the range of 10 to 2000 nm, and particularly preferably in the range of 100 to 1000 nm.

  Further, the method for forming the gas barrier layer according to the present invention is not particularly limited, but a layer formed by a plasma chemical vapor deposition method is preferable. As a gas barrier layer formed by such a plasma chemical vapor deposition method, a film substrate is disposed on the pair of film forming rollers, and plasma is generated by applying and discharging between the pair of film forming rollers. More preferably, the layer is formed by plasma chemical vapor deposition.

  When applying and discharging between the pair of film forming rollers, it is preferable to reverse the polarities of the pair of film forming rollers alternately. Further, the film forming gas used in such a plasma chemical vapor deposition method preferably contains an organosilicon compound and oxygen, and the content of oxygen in the film forming gas is the organic gas in the film forming gas. It is preferable that the amount is less than or equal to the theoretical oxygen amount necessary for complete oxidation of the entire amount of the silicon compound. In the present invention, the gas barrier layer is preferably a layer formed by a continuous film forming process.

(Deposition system)
As a method for forming the gas barrier layer according to the present invention on the transparent resin film substrate, it is preferable to employ plasma chemical vapor deposition (plasma CVD) from the viewpoint of gas barrier properties. The plasma chemical vapor deposition method may be a Penning discharge plasma type chemical vapor deposition method.

  Further, when generating plasma in the plasma chemical vapor deposition method, a method of generating plasma discharge in a space between a plurality of film forming rollers can be applied, but using a pair of film forming rollers, More preferably, a transparent resin film substrate is disposed on each of the pair of film forming rollers, and plasma is generated by discharging between the pair of film forming rollers. Furthermore, a method of forming by a discharge plasma chemical vapor deposition method using a source gas containing an organic silicon compound and an oxygen gas and having a discharge space between rollers having a magnetic field is preferable.

  Examples of a discharge plasma chemical vapor deposition apparatus having a discharge space between rollers having such a magnetic field include, for example, JP 2008-196001 A, JP 2012-84306 A, and International Publication No. 2012/046767. Reference may be made to the apparatus described.

  As a discharge plasma chemical vapor deposition apparatus applicable to the present invention, by using a pair of film forming rollers, placing a substrate on the pair of film forming rollers, and discharging between the pair of film forming rollers , While forming a gas barrier layer on a substrate existing on one film forming roller during film formation, simultaneously forming a gas barrier layer on a substrate existing on the other film forming roller This makes it possible to produce thin films efficiently, double the deposition rate, and also to form a gas barrier layer with the same structure, so that the extreme value in the carbon distribution curve can be at least doubled. Thus, it is possible to efficiently form a gas barrier layer that satisfies all of the above conditions (1) to (3) defined in the present invention.

  From the viewpoint of productivity, a method of forming the gas barrier layer on the surface of a long roll-shaped transparent resin film substrate by a roll-to-roll method is preferable. An apparatus capable of forming a gas barrier layer by such a plasma chemical vapor deposition method is not particularly limited, and includes at least a pair of film forming rollers and a plasma power source, and the pair of film forming films. It is preferable that the apparatus has a configuration capable of discharging between the rollers. For example, when the manufacturing apparatus shown in FIG. 2 is used, a roll-to-roll method is performed while using plasma chemical vapor deposition. Can also be manufactured.

  Hereinafter, the gas barrier layer forming method according to the present invention will be described in more detail with reference to FIG.

  FIG. 2 shows a gas barrier property provided with an inter-roller discharge plasma CVD apparatus having a pair of film-forming rollers provided at a position opposite to each other, which is applicable to the formation of a gas barrier layer according to the present invention. It is the schematic which shows an example of the manufacturing process of a film.

  The inter-roller discharge plasma CVD apparatus (hereinafter also referred to as plasma CVD apparatus) having a magnetic field shown in FIG. 2 mainly includes a delivery roller 11, transport rollers 21, 22, 23 and 24, a film formation roller 31 and 32, a film forming gas supply pipe 41, a plasma generation power source 51, magnetic field generators 61 and 62 installed inside the film forming rollers 31 and 32, and a winding roller 71. Further, in such a plasma CVD manufacturing apparatus, at least the film forming rollers 31 and 32, the film forming gas supply pipe 41, the plasma generating power source 51, and the magnetic field generating apparatuses 61 and 62 are not shown in a vacuum. Located in the chamber. Further, in such a plasma CVD manufacturing apparatus, a vacuum chamber (not shown) is connected to a vacuum pump (not shown), and the pressure in the vacuum chamber can be appropriately adjusted by this vacuum pump. Yes.

  In such a plasma CVD manufacturing apparatus, each film forming roller generates plasma so that a pair of film forming rollers (the film forming roller 31 and the film forming roller 32) can function as a pair of counter electrodes. It is connected to the power source 51 for use. By supplying electric power to the pair of film forming rollers (the film forming roller 31 and the film forming roller 32) from the power source 51 for generating plasma, the space between the film forming roller 31 and the film forming roller 32 can be discharged. Thus, plasma can be generated in a space (also referred to as a discharge space) between the film formation roller 31 and the film formation roller 32. In addition, since the film-forming roller 31 and the film-forming roller 32 are used as electrodes in this way, materials and designs that can be used as electrodes may be changed as appropriate. In such a plasma CVD manufacturing apparatus, it is preferable that the pair of film forming rollers (film forming rollers 31 and 32) be arranged so that their central axes are substantially parallel on the same plane. By arranging a pair of film forming rollers (film forming rollers 31 and 32) in this way, the film forming rate can be doubled, and a film having the same structure can be formed. Can be at least doubled.

  Further, the film forming roller 31 and the film forming roller 32 are characterized in that magnetic field generators 61 and 62 fixed so as not to rotate even when the film forming roller rotates are provided, respectively.

  Furthermore, as the film formation roller 31 and the film formation roller 32, known rollers can be used as appropriate. As the film forming rollers 31 and 32, those having the same diameter are preferably used from the viewpoint of forming a thin film (gas barrier layer) more efficiently. The diameters of the film forming rollers 31 and 32 are preferably in the range of 100 to 1000 mmφ, particularly in the range of 100 to 700 mmφ, from the viewpoint of discharge conditions, chamber space, and the like. If the diameter is 100 mmφ or more, it is preferable that the plasma discharge space is not reduced, the productivity is not deteriorated, the total amount of heat of the plasma discharge can be prevented from being applied to the film in a short time, and the residual stress is hardly increased. On the other hand, a diameter of 1000 mmφ or less is preferable because practicality can be maintained in terms of device design including uniformity of the plasma discharge space.

  Further, as the delivery roller 11 and the transport rollers 21, 22, 23, and 24 used in such a plasma CVD manufacturing apparatus, known rollers can be appropriately selected and used. The winding roller 71 is not particularly limited as long as it can wind the resin base material 1 on which the gas barrier layer is formed, and a known roller can be used as appropriate.

  As the film forming gas supply pipe 41, a pipe capable of supplying or discharging the source gas and the oxygen gas at a predetermined rate can be appropriately used. Furthermore, as the plasma generating power source 51, a conventionally known power source for a plasma generating apparatus can be used. Such a power source 51 for generating plasma supplies power to the film forming roller 31 and the film forming roller 32 connected thereto, and makes it possible to use these as counter electrodes for discharge. As such a plasma generation power source 51, since it is possible to efficiently perform plasma CVD processing, a power source (AC power source or the like) capable of alternately reversing the polarities of a pair of film forming rollers is used. It is preferable to use it. In addition, since the plasma generating power source 51 can perform the plasma CVD process more efficiently, the applied power can be in the range of 100 W to 10 kW, and the AC frequency is 50 Hz. It is more preferable that it can be in the range of ˜500 kHz. As the magnetic field generators 61 and 62, known magnetic field generators can be used as appropriate.

  Using a plasma CVD apparatus as shown in FIG. 2, for example, the type of source gas, the power supplied to the electrode drum of the plasma generator (film formation roller), the strength of the magnetic field generator, the pressure in the vacuum chamber, and the film formation The gas barrier layer according to the present invention can be formed by appropriately adjusting the diameter of the roller and the conveying speed of the resin base material. That is, using the plasma CVD apparatus shown in FIG. 2, a magnetic field is generated between a pair of film forming rollers (film forming rollers 31 and 32) while supplying a film forming gas (raw material gas, etc.) into the vacuum chamber. By performing plasma discharge, the film forming gas (raw material gas or the like) is decomposed by plasma, and on the surface of the resin base material 1 on the film forming roller 31 and on the surface of the resin base material 1 on the film forming roller 32. The gas barrier layer according to the present invention is formed by the plasma CVD method. In such film formation, the resin base material 1 is conveyed by the delivery roller 11 and the film formation roller 31, respectively, so that the resin base material 1 is formed by a roll-to-roll continuous film formation process. The gas barrier layer is formed on the surface.

<Raw gas>
The source gas constituting the film forming gas used for forming the gas barrier layer according to the present invention can be appropriately selected according to the material of the gas barrier layer to be formed, and at least an organosilicon compound containing silicon is used. Is preferred.

  Examples of the organosilicon compound applicable to the present invention include hexamethyldisiloxane, 1,1,3,3-tetramethyldisiloxane, vinyltrimethylsilane, methyltrimethylsilane, hexamethyldisilane, methylsilane, dimethylsilane, and trimethyl. Examples thereof include silane, diethylsilane, propylsilane, phenylsilane, vinyltriethoxysilane, vinyltrimethoxysilane, tetramethoxysilane, tetraethoxysilane, phenyltrimethoxysilane, methyltriethoxysilane, and octamethylcyclotetrasiloxane. Among these organosilicon compounds, hexamethyldisiloxane and 1,1,3,3-tetramethyldisiloxane are preferable from the viewpoints of handling in film formation and gas barrier properties of the obtained gas barrier layer. Moreover, these organosilicon compounds can be used individually by 1 type or in combination of 2 or more types.

<Reaction gas>
In addition to the source gas, a reactive gas may be used as the film forming gas. As such a reactive gas, a gas that reacts with the raw material gas to become an inorganic compound such as an oxide or a nitride can be appropriately selected and used. As a reaction gas for forming an oxide, for example, oxygen or ozone can be used. Moreover, as a reactive gas for forming nitride, nitrogen and ammonia can be used, for example. These reaction gases can be used alone or in combination of two or more. For example, when forming an oxynitride, a reaction gas for forming an oxide and a nitride are formed. The reaction gas can be used in combination.

<Carrier gas>
In the film forming gas, since a source gas is supplied into the vacuum chamber, a carrier gas may be used as necessary. Further, as the film forming gas, a discharge gas may be used as necessary in order to generate plasma discharge. As such carrier gas and discharge gas, known ones can be used as appropriate, and for example, rare gases such as helium, argon, neon, xenon, hydrogen gas, and nitrogen gas can be used.

<Reaction of deposition gas>
When the film forming gas contains a source gas and a reactive gas, the ratio of the source gas and the reactive gas is the amount of the reactive gas that is theoretically necessary to completely react the raw material gas and the reactive gas. It is preferable not to make the ratio of the reaction gas excessively higher than the ratio of. If the ratio of the reaction gas is excessive, a thin film that satisfies all of the above conditions (1) to (3) cannot be obtained. When the deposition gas contains an organosilicon compound and oxygen, the amount of oxygen should be less than or equal to the theoretical oxygen amount necessary for complete oxidation of the entire amount of the organosilicon compound in the deposition gas. preferable.

Hereinafter, as a representative example, a system of hexamethyldisiloxane (an organosilicon compound, also referred to as HMDSO, (CH ₃ ) ₆ Si ₂ O) as a source gas and oxygen (O ₂ ) as a reaction gas will be described.

A film-forming gas containing hexamethyldisiloxane ((CH ₃ ) ₆ Si ₂ O) as a source gas and oxygen (O ₂ ) as a reaction gas is reacted by a plasma CVD method to form a silicon-oxygen system ( When forming a thin film of Si _x O _y ), a reaction represented by the following reaction formula (1) occurs by the film forming gas, and a thin film made of silicon dioxide SiO ₂ is formed.

Reaction formula (1): (CH ₃ ) ₆ Si ₂ O + 12O ₂ → 6CO ₂ + 9H ₂ O + 2SiO ₂
In such a reaction, the amount of oxygen required to completely oxidize 1 mol of hexamethyldisiloxane is 12 mol. Therefore, when the film forming gas contains 12 moles or more of oxygen with respect to 1 mole of hexamethyldisiloxane and is completely reacted, a uniform silicon dioxide film is formed. The ratio is controlled to a flow rate equal to or less than the raw material ratio of the complete reaction, which is the theoretical ratio, and the incomplete reaction is performed. That is, it is necessary to set the amount of oxygen to less than 12 moles of the stoichiometric ratio with respect to 1 mole of hexamethyldisiloxane.

  In the actual reaction in the chamber of the plasma CVD apparatus, the raw material hexamethyldisiloxane and the reaction gas, oxygen, are supplied from the gas supply unit to the film formation region to form a film. Even if the molar amount (flow rate) is 12 times the molar amount (flow rate) of the starting hexamethyldisiloxane, the reaction cannot actually proceed completely, and oxygen content It is considered that the reaction is completed only when the amount is supplied in a large excess with respect to the stoichiometric ratio. For example, in order to obtain silicon oxide by complete oxidation by the plasma CVD method, the molar amount (flow rate) of oxygen may be 20 times or more the molar amount (flow rate) of hexamethyldisiloxane as a raw material. Therefore, the molar amount (flow rate) of oxygen with respect to the molar amount (flow rate) of hexamethyldisiloxane as a raw material is preferably 12 times or less, more preferably 10 times or less, which is the stoichiometric ratio. It is. By supplying hexamethyldisiloxane and oxygen at such a ratio, carbon atoms and hydrogen atoms in hexamethyldisiloxane that have not been completely oxidized are taken into the gas barrier layer and have a desired elemental composition profile. A gas barrier layer can be formed, and excellent gas barrier properties and bending resistance can be imparted to the resulting gas barrier film. If the molar amount (flow rate) of oxygen with respect to the molar amount (flow rate) of hexamethyldisiloxane in the deposition gas is too small, unoxidized carbon atoms and hydrogen atoms will be excessively taken into the gas barrier layer. become. In this case, the transparency of the gas barrier layer is lowered, and such a gas barrier film is flexible for electronic devices such as devices that require transparency such as organic EL devices and organic thin film solar cells. It can no longer be used for the substrate. Therefore, 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.

<Degree of vacuum>
The pressure (degree of vacuum) in the vacuum chamber can be appropriately adjusted according to the type of the raw material gas and the like, but is preferably in the range of about 0.5 to 100 Pa.

<Roller film formation>
In a plasma CVD method using a plasma CVD apparatus or the like as shown in FIG. 2, an electrode drum connected to a plasma generation power source 51 (in FIG. The electric power applied to the film rollers 31 and 32) can be adjusted as appropriate according to the type of source gas, the pressure in the vacuum chamber, etc., and cannot be specified in general. However, it is preferable to be within a range of about 0.1 to 10 kW. If the applied power is in such a range, no generation of particles (illegal particles) is observed, and the amount of heat generated during film formation is within the control range. It is also possible to prevent thermal deformation of the base material, performance deterioration due to heat, and generation of wrinkles during film formation. In addition, it is possible to prevent damage to the film forming roller due to melting of the resin base material by heat and generation of a large current discharge between the bare film forming rollers.

  Although the conveyance speed (line speed) of the resin base material 1 can be suitably adjusted according to the kind of raw material gas, the pressure in a vacuum chamber, etc., it is preferable to set it as the range of 0.25-100 m / min. More preferably, it is in the range of 0.5 to 20 m / min. If the line speed is within the above range, wrinkles due to the heat of the resin base material hardly occur, and the thickness of the formed gas barrier layer can be sufficiently controlled.

<< Layer structure of organic EL element >>
Next, although the specific example of the layer structure of the organic EL element which concerns on this invention is shown below, this invention is not limited to these.

(I) Anode / hole injection layer / hole transport layer / light emitting layer / electron injection layer / cathode (ii) Anode / hole injection layer / hole transport layer / light emitting layer / electron transport layer / electron injection layer / cathode [Organic layer]
Although it does not specifically limit as an organic layer which comprises the organic layer unit in this invention, For example, a hole injection layer, a positive hole transport layer, a light emitting layer, an electron carrying layer, and an electron which were illustrated to said (ii), for example An injection layer etc. can be mentioned.

  In the present invention, a plurality of organic layers including a hole injection layer, a hole transport layer, a light emitting layer, and an electron transport layer are prepared by dissolving each organic layer forming material (organic material) in a solvent. It is formed by applying sequentially using a forming coating solution.

  As a solvent used for the preparation of the coating solution for forming an organic layer according to the present invention, the target organic material can be dissolved, and at least less than Tg + 30 ° C. of the transparent resin film substrate used for preparing the organic EL element. A solvent having a boiling point is selected.

  The type of solvent applicable to the present invention varies depending on the type of resin film substrate to be applied. For example, alcohols, fatty acid esters, ketones, aromatic hydrocarbons, halogenated hydrocarbons, fats Group hydrocarbons, amines, nitriles, ethers and the like. Specifically, for example, methanol (boiling point: 64.7 ° C), ethanol (boiling point: 78.3 ° C), isopropyl alcohol (boiling point: 82.3 ° C), 1-propanol (boiling point: 97.2 ° C), alcohols such as n-butanol (boiling point: 117.7 ° C.), s-butanol (boiling point: 99.5 ° C.), t-butanol (boiling point: 82.5 ° C.), acetone (boiling point: 56.1 ° C.), Ketones such as methyl ethyl ketone (boiling point: 79.6 ° C), cyclohexanone (boiling point: 155.7 ° C), ethyl acetate (boiling point: 77.1 ° C), n-butyl acetate (boiling point: 126.1 ° C), isopropyl acetate (Boiling point: 88.6 ° C), fatty acid esters such as isobutyl acetate (boiling point: 116.6 ° C), butyl chloride (boiling point: 78.5 ° C), hexyl chloride (boiling point: 134.5 ° C), chlorobenzene (boiling point) : 131.7 ° C), halogenated hydrocarbons such as dichloropropane (boiling point: 96.8 ° C), tetrachloroethylene (boiling point: 121.2 ° C), toluene (boiling point: 110.6 ° C), o-xylene (boiling point) 144.4 ° C.), mesitylene (boiling point: 164.7 ° C.), aromatic hydrocarbons such as styrene (boiling point: 145 ° C.), aliphatic hydrocarbons such as cyclohexane (boiling point: 80.7 ° C.), N, Amines such as N-dimethylformamide (DMF, boiling point: 153 ° C.), nitriles such as propionitrile (boiling point: 97.2 ° C.), diisopropyl ether (boiling point: 68.5 ° C.), 1,4-dioxane ( Boiling point: 101.4 ° C., ether such as tetrahydrofuran (boiling point: 65 ° C.), organic solvent such as dimethyl sulfoxide (DMSO, boiling point: 189 ° C.), water (boiling point: 100 ° C.) It can be used. It is preferable to select and use each of the above solvents from the viewpoint of improving the aggregation state of the organic material and the like.

  The boiling point of the solvent according to the present invention is a value measured under atmospheric pressure, and is described in detail in, for example, “Newly published Solvent Pocket Book” (edited by the Society for Synthetic Organic Chemistry, published by Ohm Corporation, 1994, 1st edition). Data are listed and can be used as a reference.

  In addition, when preparing each organic layer coating liquid, a dispersion device or the like can be used, and as an applicable dispersion method, a dispersion method such as ultrasonic dispersion, high shear force dispersion or media dispersion can be applied. it can.

  Since the organic layer forming material according to the present invention varies depending on the type of the organic layer, a specific forming material will be described in the detailed description of the layer configuration of the organic EL below. In addition, the coating liquid for organic layer formation and the organic layer formation material change the name according to the name of the organic layer. For example, the organic layer forming coating liquid and the organic layer forming material in the light emitting layer are referred to as the light emitting layer forming coating liquid and the light emitting layer forming material.

  Hereafter, the detail is further demonstrated regarding the structure of each organic layer of the organic EL of this invention.

(Light emitting layer)
The light emitting layer according to the present invention is a layer that emits light by recombination of electrons and holes injected from the electrode, the electron transport layer, or the hole transport layer, and the light emitting region is within the layer of the light emitting layer. Or the interface area | region of a light emitting layer and an adjacent layer may be sufficient.

  The layer thickness of the light emitting layer is not particularly limited, but from the viewpoint of improving the uniformity of the light emitting layer to be formed and preventing application of unnecessary high voltage at the time of light emission, and improving the stability of the emission color against the driving current. It is preferable to adjust within the range of 2 to 200 nm, and more preferably within the range of 5 to 100 nm.

  As the light emitting layer forming material according to the present invention, a metal complex compound can be used. In addition, a host compound can be used together with a metal complex compound. The molecular weight of the light emitting layer forming material is not particularly limited, but is preferably 2000 or less.

  As the metal complex compound according to the present invention, a fluorescent dopant or a phosphorescent dopant can be used. Among these, from the viewpoint of obtaining an organic EL device with higher luminous efficiency, the metal complex compound used in the light emitting layer of the organic EL device according to the present invention preferably contains a phosphorescent dopant.

  A phosphorescent dopant 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.). It is defined as a compound of 01 or more, and a preferable phosphorescence quantum yield is 0.1 or more.

  The phosphorescence 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. Although the phosphorescence quantum yield in a solution can be measured using various solvents, the phosphorescence dopant applied in the present invention is the above phosphorescence quantum yield (0.01 or more) in any solvent. Should be achieved.

  The following two types of light emission principles using phosphorescent dopants can be mentioned. One is the recombination of carriers on the light-emitting host where carriers are transported, and the excited state of the light-emitting host is generated. It is an energy transfer type in which light emission from the phosphorescent dopant is obtained by transferring to the dopant. On the other hand, the phosphorescent dopant becomes a carrier trap, and carrier recombination occurs on the phosphorescent dopant, and light emission from the phosphorescent dopant. In either case, the excited state energy of the phosphorescent dopant is required to be lower than the excited state energy of the light emitting host.

  As a phosphorescence dopant, it can select from the well-known thing conventionally used for the light emitting layer of an organic EL element, and can use it suitably. Specific examples of typical compounds used as phosphorescent dopants are shown below, but the present invention is not limited thereto. These compounds are described, for example, in Inorg. Chem. 40, 1704-1711, etc.

  Among the phosphorescent dopants exemplified above, an iridium complex having a structure represented by the following general formula (1) is particularly preferably used as the metal complex having a blue emission wavelength.

In the general formula (1), Z represents a hydrocarbon ring group or a heterocyclic group. P ₁ -L ₁ -P ₂ represents a bidentate ligand, and P ₁ and P ₂ each independently represent a carbon atom, a nitrogen atom, or an oxygen atom. L1 represents an atomic group forming a ligand bidentate with _{P 1} and _{P 2.} R _{81 to} R ₈₆ each represent a hydrogen atom or a substituent. j1 represents an integer of 1 to 3, j2 represents an integer of 0 to 2, and j1 + j2 is 2 or 3. M ₁ represents a group 8-10 transition metal element in the periodic table.

In the general formula (1), examples of the bidentate ligand represented by P ₁ -L ₁ -P ₂ include substituted or unsubstituted phenylpyridine, phenylpyrazole, phenylimidazole, phenyltriazole, phenyltetrazole, Examples include pyraza ball, acetylacetone, and picolinic acid.

  Examples of the hydrocarbon ring group represented by Z include a non-aromatic hydrocarbon ring group and an aromatic hydrocarbon ring group. Examples of the non-aromatic hydrocarbon ring group include a cyclopropyl group, a cyclopentyl group, and a cyclohexyl group. And may be substituted or unsubstituted.

  Examples of the aromatic hydrocarbon ring group (also referred to as aromatic hydrocarbon group, aryl group, etc.) include, for example, phenyl group, p-chlorophenyl group, mesityl group, tolyl group, xylyl group, naphthyl group, anthryl group, azulenyl. Group, acenaphthenyl group, fluorenyl group, phenanthryl group, indenyl group, pyrenyl group, biphenylyl group and the like. These groups may be substituted or unsubstituted.

  Examples of the heterocyclic group represented by Z include a non-aromatic heterocyclic group and an aromatic heterocyclic group. Examples of the non-aromatic heterocyclic group include an epoxy ring, an aziridine ring, a thiirane ring, Oxetane ring, azetidine ring, thietane ring, tetrahydrofuran ring, dioxolane ring, pyrrolidine ring, pyrazolidine ring, imidazolidine ring, oxazolidine ring, tetrahydrothiophene ring, sulfolane ring, thiazolidine ring, ε-caprolactone ring, ε-caprolactam ring, piperidine ring , Hexahydropyridazine ring, hexahydropyrimidine ring, piperazine ring, morpholine ring, tetrahydropyran ring, 1,3-dioxane ring, 1,4-dioxane ring, trioxane ring, tetrahydrothiopyran ring, thiomorpholine ring, thiomorpholine- 1,1-dioxide ring, pyranose ring And groups derived from a diazabicyclo [2,2,2] -octane ring and the like.

In the organometallic complex having the structure represented by the general formula (1), R _{81 to} R ₈₆ each represent a hydrogen atom or a substituent. Examples of the substituent include, for example, an alkyl group (for example, a methyl group, Ethyl group, propyl group, isopropyl group, t-butyl group, pentyl group, hexyl group, octyl group, dodecyl group, tridecyl group, tetradecyl group, pentadecyl group, etc.), cycloalkyl group (for example, cyclopentyl group, cyclohexyl group, etc.) An alkenyl group (eg, vinyl group, allyl group, etc.), an alkynyl group (eg, ethynyl group, propargyl group, etc.), an aromatic hydrocarbon ring group (aromatic carbocyclic group, aryl group, etc., for example, a phenyl group P-chlorophenyl group, mesityl group, tolyl group, xylyl group, naphthyl group, anthryl group, azulenyl group, acenaphthe Group, fluorenyl group, phenanthryl group, indenyl group, pyrenyl group, biphenylyl group, etc.), aromatic heterocyclic group (for example, pyridyl group, pyrimidinyl group, furyl group, pyrrolyl group, imidazolyl group, benzimidazolyl group, pyrazolyl group, pyrazinyl group) Group, triazolyl group (for example, 1,2,4-triazol-1-yl group, 1,2,3-triazol-1-yl group), oxazolyl group, benzoxazolyl group, thiazolyl group, isoxazolyl group, isothiazolyl Group, furazanyl group, thienyl group, quinolyl group, benzofuryl group, dibenzofuryl group, benzothienyl group, dibenzothienyl group, indolyl group, carbazolyl group, carbolinyl group, diazacarbazolyl group (which constitutes the carboline ring of the carbolinyl group) One of the carbon atoms Quinoxalinyl group, pyridazinyl group, triazinyl group, quinazolinyl group, phthalazinyl group, etc.), heterocyclic group (for example, pyrrolidyl group, imidazolidyl group, morpholyl group, oxazolidyl group, etc.), alkoxy group (for example, Methoxy group, ethoxy group, propyloxy group, pentyloxy group, hexyloxy group, octyloxy group, dodecyloxy group, etc.), cycloalkoxy group (for example, cyclopentyloxy group, cyclohexyloxy group, etc.), aryloxy group (for example, , Phenoxy group, naphthyloxy group, etc.), alkylthio group (eg, methylthio group, ethylthio group, propylthio group, pentylthio group, hexylthio group, octylthio group, dodecylthio group, etc.), cycloalkylthio group (eg, cyclopentylthio group) , Cyclohexylthio group, etc.), arylthio group (eg, phenylthio group, naphthylthio group, etc.), alkoxycarbonyl group (eg, methyloxycarbonyl group, ethyloxycarbonyl group, butyloxycarbonyl group, octyloxycarbonyl group, dodecyloxycarbonyl group) Etc.), aryloxycarbonyl groups (eg, phenyloxycarbonyl group, naphthyloxycarbonyl group, etc.), sulfamoyl groups (eg, aminosulfonyl group, methylaminosulfonyl group, dimethylaminosulfonyl group, butylaminosulfonyl group, hexylaminosulfonyl group) Cyclohexylaminosulfonyl group, octylaminosulfonyl group, dodecylaminosulfonyl group, phenylaminosulfonyl group, naphthylaminosulfonyl group, 2-pyridyl Minosulfonyl group, etc.), acyl group (for example, acetyl group, ethylcarbonyl group, propylcarbonyl group, pentylcarbonyl group, cyclohexylcarbonyl group, octylcarbonyl group, 2-ethylhexylcarbonyl group, dodecylcarbonyl group, phenylcarbonyl group, naphthylcarbonyl) Group, pyridylcarbonyl group, etc.), acyloxy group (for example, acetyloxy group, ethylcarbonyloxy group, butylcarbonyloxy group, octylcarbonyloxy group, dodecylcarbonyloxy group, phenylcarbonyloxy group), amide group (for example, methylcarbonyl group) Amino group, ethylcarbonylamino group, dimethylcarbonylamino group, propylcarbonylamino group, pentylcarbonylamino group, cyclohexylcarbonylamino group, Ruhexylcarbonylamino group, octylcarbonylamino group, dodecylcarbonylamino group, phenylcarbonylamino group, naphthylcarbonylamino group, etc.), carbamoyl group (for example, aminocarbonyl group, methylaminocarbonyl group, dimethylaminocarbonyl group, propylaminocarbonyl group) Pentylaminocarbonyl group, cyclohexylaminocarbonyl group, octylaminocarbonyl group, 2-ethylhexylaminocarbonyl group, dodecylaminocarbonyl group, phenylaminocarbonyl group, naphthylaminocarbonyl group, 2-pyridylaminocarbonyl group, etc.), ureido group (for example, Methylureido group, ethylureido group, pentylureido group, cyclohexylureido group, octylureido group, dodecylureido group, Nylureido group, naphthylureido group, 2-pyridylaminoureido group, etc.), sulfinyl group (for example, methylsulfinyl group, ethylsulfinyl group, butylsulfinyl group, cyclohexylsulfinyl group, 2-ethylhexylsulfinyl group, dodecylsulfinyl group, phenylsulfinyl group, naphthyl) Sulfinyl group, 2-pyridylsulfinyl group, etc.), alkylsulfonyl group (for example, methylsulfonyl group, ethylsulfonyl group, butylsulfonyl group, cyclohexylsulfonyl group, 2-ethylhexylsulfonyl group, dodecylsulfonyl group, etc.), arylsulfonyl group or hetero An arylsulfonyl group (eg, phenylsulfonyl group, naphthylsulfonyl group, 2-pyridylsulfonyl group, etc.), amino group (eg, amino group, A ruamino group, a dimethylamino group, a butylamino group, a cyclopentylamino group, a 2-ethylhexylamino group, a dodecylamino group, an anilino group, a naphthylamino group, a 2-pyridylamino group, etc., a halogen atom (for example, a fluorine atom, a chlorine atom, Bromine atom etc.), fluorinated hydrocarbon group (eg fluoromethyl group, trifluoromethyl group, pentafluoroethyl group, pentafluorophenyl group etc.), cyano group, nitro group, hydroxy group, mercapto group, silyl group (eg , Trimethylsilyl group, triisopropylsilyl group, triphenylsilyl group, phenyldiethylsilyl group, etc.). These substituents may be further substituted with the above substituents. A plurality of these substituents may be bonded to each other to form a ring.

  Among them, aromatic hydrocarbon ring groups (also called aromatic carbocyclic groups, aryl groups, etc., for example, phenyl group, p-chlorophenyl group, mesityl group, tolyl group, xylyl group, naphthyl group, anthryl group, azulenyl group, acenaphthenyl group, etc. Group, fluorenyl group, phenanthryl group, indenyl group, pyrenyl group, biphenylyl group, etc.) or aromatic heterocyclic group (for example, furyl group, thienyl group, pyridyl group, pyridazinyl group, pyrimidinyl group, pyrazinyl group, triazinyl group, imidazolyl) Group, pyrazolyl group, thiazolyl group, quinazolinyl group, phthalazinyl group and the like) are particularly preferable.

  In the present invention, when the light emitting layer contains a metal complex compound, the light emitting layer may contain one kind of metal complex compound or two or more kinds of metal complex compounds having different emission maximum wavelengths. . In addition, by using a plurality of types of light emitting materials, it is possible to mix different light emission colors, and thus any light emission color including white can be obtained. In the present invention, the light emitting layer preferably contains a light emitting dopant having a molecular weight of 2000 or less.

  As a host compound contained in the light emitting layer of the organic EL device according to the present invention, 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 a light emitting layer.

  As the host compound, known host compounds may be used alone or in combination of two or more. 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.

  The host compound used in the present invention may be a conventionally known low molecular compound or a high molecular compound having a repeating unit, and a low molecular compound having a polymerizable group such as a vinyl group or an epoxy group (evaporation polymerizable light emitting host). However, in the present invention, it is preferable to use a light emitting host compound having a molecular weight of 2000 or less for the light emitting layer.

  As the known host compound, a compound having a hole transporting ability and an electron transporting ability, preventing an increase in the wavelength of light emission, and having a high Tg (glass transition temperature) is preferable. Here, the glass transition point (Tg) is a value obtained by a method based on JIS-K-7121 using DSC (Differential Scanning Colorimetry).

  Specific examples of known host compounds include compounds described in the following documents. For example, Japanese Patent Application Laid-Open Nos. 2001-257076, 2002-308855, 2001-313179, 2002-319491, 2001-357777, 2002-334786, 2002-8860 Gazette, 2002-334787 gazette, 2002-15871 gazette, 2002-334788 gazette, 2002-43056 gazette, 2002-334789 gazette, 2002-75645 gazette, 2002-338579 gazette. No. 2002-105445, No. 2002-343568, No. 2002-141173, No. 2002-352957, No. 2002-203683, No. 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. 2002-302516, 2002-305083, 2002-305084, 2002-308837, and the like.

  The host compound used in the present invention is preferably a carbazole derivative, more preferably a dibenzofuran compound which is a carbazole derivative.

(Injection layer)
In the organic EL device according to the present invention, the injection layer can be provided as necessary. As the injection layer, there are an electron injection layer and a hole injection layer. As described above, the injection layer may exist between the anode and the light emitting layer or the hole transport layer and between the cathode and the light emitting layer or the electron transport layer.

  The injection layer referred to in the present invention is a layer provided between the electrode and the organic layer in order to lower the driving voltage and improve the light emission luminance. “The organic EL element and its forefront of industrialization (November 30, 1998, NTS) The details are described in Chapter 2, “Electrode Material” (pages 123 to 166) of the second volume of “published by the company”.

  Details of the hole injection layer and its constituent materials are described, for example, in JP-A-9-45479, JP-A-9-260062, and JP-A-8-288069.

  Examples of the forming material applicable to the formation of the hole injection layer include triazole derivatives, oxadiazole derivatives, imidazole derivatives, pyrazoline derivatives and pyrazolone derivatives, phenylenediamine derivatives, arylamine derivatives, amino-substituted chalcone derivatives, oxazole derivatives, Examples include polymers containing styryl anthracene derivatives, fluorenone derivatives, hydrazone derivatives, stilbene derivatives, silazane derivatives, aniline copolymers, polyarylalkane derivatives, or conductive polymers, preferably polythiophene derivatives, polyaniline derivatives, polypyrrole derivatives. More preferably a polythiophene derivative.

  Details of the electron injection layer and its constituent materials are described in, for example, JP-A-6-325871, JP-A-9-17574, and JP-A-10-74586.

  Examples of the forming material applicable to the formation of the electron injection layer include a metal compound. Specific examples include a metal buffer layer typified by strontium and aluminum, an alkali metal compound buffer layer typified by lithium fluoride, Examples thereof include an alkaline earth metal compound buffer layer typified by magnesium fluoride and an oxide buffer layer typified by aluminum oxide. In the present invention, the buffer layer (injection layer) is preferably a very thin layer, preferably potassium fluoride or sodium fluoride. The layer thickness is about 0.1 to 5 μm, preferably in the range of 0.1 to 100 nm, more preferably in the range of 0.5 to 10 nm, and most preferably in the range of 0.5 to 4 nm.

(Hole transport layer)
Examples of the hole transport layer forming material that can be used for forming the hole transport layer according to the present invention include the same compounds that can be applied in the hole injection layer. A porphyrin compound, an aromatic tertiary amine compound, and a styrylamine compound can be mentioned. Among them, it is particularly preferable to use 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 (abbreviation: TPD); 2,2-bis (4-di-p-tolylaminophenyl) propane; -Bis (4-di-p-tolylaminophenyl) cyclohexane; N, N, N ', N'-tetra-p-tolyl-4,4'-diaminobiphenyl; 1,1-bis (4-di-p -Tolylaminophenyl) -4-phenylcyclohexane; bis (4-dimethylamino-2-methylphenyl) phenylmethane; bis (4-di-p-tolylaminophenyl) phenylmethane; N, N'-diphenyl-N, '-Di (4-methoxyphenyl) -4,4'-diaminobiphenyl; N, N, N', N'-tetraphenyl-4,4'-diaminodiphenyl ether; 4,4'-bis (diphenylamino) c 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 further described in US Pat. No. 5,061,569. Having two condensed aromatic rings in the molecule, for example, 4,4'-bis [N- (1-naphthyl) -N-phenylamino] biphenyl (abbreviation: NPD), JP, 4,4 ', 4 "-tris [N- (3-methylphenyl) -N-phenylamino] triphenyl in which triphenylamine units described in Japanese Patent No. 4-308688 are linked in three starburst types And amine (abbreviation: MTDATA).

  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, inorganic compounds such as p-type-Si and p-type-SiC can also be used as the hole injection layer material and the hole transport layer material.

  JP-A-4-297076, JP-A-2000-196140, JP-A-2001-102175, J. Pat. Appl. Phys. , 95, 5773 (2004), JP-A-11-251067, J. MoI. Huang et. al. It is also possible to use a hole transport layer material having so-called p-type semiconducting properties as described in the literature (Applied Physics Letters 80 (2002), p. 139) and JP-T 2003-519432.

  Although there is no restriction | limiting in particular about the layer thickness of a positive hole transport layer, Usually, 5 nm-about 5 micrometers, Preferably it exists in the range of 5-200 nm. The hole transport layer may have a single layer structure composed of one or more of the above materials.

(Electron transport layer)
The electron transport layer as used in the present invention contains a material having a function of transporting electrons, and in a broad sense, an electron injection layer and a hole blocking layer are also included in the electron transport layer. The electron transport layer can be provided as a single layer or a plurality of layers.

  Conventionally, when a single electron transport layer or a plurality of electron transport layers are formed, an electron transport layer material (a hole blocking layer material used for an electron transport layer provided adjacent to the light emitting layer on the cathode side) is used. As long as it has a function of transmitting electrons injected from the cathode to the light-emitting layer. As such a material, any one of conventionally known compounds may be selected and used. Examples thereof include metal complexes such as a fluorene derivative, a carbazole derivative, an azacarbazole derivative, an oxadiazole derivative, a trizole derivative, a cylola derivative, a pyridine derivative, a pyrimidine derivative, and an 8-quinolinol derivative.

  In addition, metal-free or metal phthalocyanine, or those having terminal ends substituted with alkyl groups or sulfonic acid groups can be preferably used as the electron transport layer material.

  Among these, carbazole derivatives, azacarbazole derivatives, pyridine derivatives and the like are preferable in the present invention, and dibenzofuran compounds which are carbazole derivatives are more preferable.

  Although there is no restriction | limiting in particular about the layer thickness of an electron carrying layer, Usually, 5 nm-about 5 micrometers, Preferably it exists in the range of 5-200 nm. The electron transport layer may have a single layer structure composed of one or more of the above materials.

  In addition, a material doped with impurities as a guest material can be used for the electron transport layer with high 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.

  In the present invention, it is preferable to apply an alkali metal salt of an organic substance to the electron transport layer. There are no particular restrictions on the type of organic substance, but formate, acetate, propionic acid, butyrate, valerate, caproate, enanthate, caprylate, oxalate, malonate, succinic acid Salt, benzoate, phthalate, isophthalate, terephthalate, salicylate, pyruvate, lactate, malate, adipate, mesylate, tosylate, benzenesulfonate Preferably, formate, acetate, propionate, butyrate, valerate, caprate, enanthate, caprylate, oxalate, malonate, succinate, benzoate, and more Alkali metal salts of aliphatic carboxylic acids such as formate, acetate, propionate, butyrate are preferred, and the aliphatic carboxylic acid preferably has 4 or less carbon atoms. Most preferred is acetate.

  The kind of alkali metal of the organic alkali metal salt is not particularly limited, and examples thereof include Na, K, and Cs, preferably K, Cs, and more preferably Cs. Examples of the alkali metal salt of the organic substance include a combination of the organic substance and the alkali metal, preferably, formic acid Li, formic acid K, formic acid Na, formic acid Cs, acetic acid Li, acetic acid K, Na acetate, acetic acid Cs, propionic acid Li, Propionic acid Na, propionic acid K, propionic acid Cs, oxalic acid Li, oxalic acid Na, oxalic acid K, oxalic acid Cs, malonic acid Li, malonic acid Na, malonic acid K, malonic acid Cs, succinic acid Li, succinic acid Na, succinic acid K, succinic acid Cs, benzoic acid Li, benzoic acid Na, benzoic acid K, benzoic acid Cs, more preferably Li acetate, K acetate, Na acetate, Cs acetate, most preferably Cs acetate.

  The content of these dope materials is preferably in the range of 1.5 to 35% by mass, more preferably in the range of 3 to 25% by mass, most preferably 5 to 5%, based on the electron transport layer to be added. It is in the range of 15 mass%.

〔anode〕
As the anode constituting the organic EL device according to the present invention, an anode using a metal, an alloy, an electrically conductive compound and a mixture thereof having a high work function (4 eV or more) is preferably used. Specific examples of such an electrode material include metals such as Au, and conductive transparent materials such as CuI, indium tin oxide (abbreviation: 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, these electrode materials may be formed into a thin film by a method such as vapor deposition or sputtering, and a desired pattern may be formed by photolithography, or when the pattern accuracy is not so required, for example, the required accuracy is 100 μm. If it is about the above, a pattern may be formed through a mask having a desired shape at the time of vapor deposition or sputtering of the electrode material. Or when using the substance which can be apply | coated like an organic electroconductivity compound, wet film-forming methods, such as a printing system and a wet coating system, can also be used. When light emission is taken out from this anode forming surface, the transmittance of the anode is desirably 10% or more, and the sheet resistance as the anode is preferably several hundred Ω / □ or less. Further, although the film thickness depends on the material, it is usually in the range of 10 to 1000 nm, preferably in the range of 10 to 200 nm.

〔cathode〕
As the cathode, a material having a work function (4 eV or less) metal (hereinafter 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, Magnesium / aluminum mixtures, magnesium / indium mixtures, aluminum / aluminum oxide (Al ₂ O ₃ ) mixtures, lithium / aluminum mixtures, aluminum and the like are preferred. 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 the cathode is preferably several hundred Ω / □ or less, and the film thickness is usually selected in the range of 10 nm to 5 μm, preferably in the range of 50 to 200 nm. In order to transmit the emitted light, it is advantageous in terms of improving the light emission luminance that either the anode or the cathode of the organic EL element is transparent or translucent.

  Moreover, after producing the said metal in the film thickness range of 1-20 nm as a cathode, the transparent or semi-transparent cathode can be produced by forming the electroconductive transparent material quoted by description of the anode on it. By applying this, it is possible to produce an organic EL element in which both the anode and the cathode are transparent.

<< Specific Manufacturing Method of Organic Electroluminescence Element >>
As an example of the method for producing an organic EL device of the present invention, a method for producing an organic EL device comprising an anode / hole injection layer / hole transport layer / light emitting layer / electron transport layer / electron injection layer / cathode will be described. .

  In the first method of the method for producing an organic EL device of the present invention, an organic layer unit composed of a hole injection layer, a hole transport layer, a light emitting layer, and an electron transport layer is prepared by using a material for forming each organic layer as a solvent. The coating liquid used for forming each organic layer of the hole injection layer, the hole transport layer, the light emitting layer, and the electron transport layer is formed by sequentially coating each organic layer forming coating liquid prepared by dissolving in One heat treatment at the heat treatment temperature defined by the following formula (a) in the process from the formation of the organic layer containing the solvent having the highest boiling point among the contained solvents to the formation of the cathode. It is characterized by giving.

Formula (a): (The boiling point of the solvent having the highest boiling point −10 ° C. among the solvents used for forming the hole injection layer, the hole transport layer, the light emitting layer, the electron transport layer, and the electron injection layer, which are organic layers) ≦ (Heat treatment temperature) ≦ (Glass transition temperature of transparent resin film substrate (Tg) + 20 ° C.)
For example, among the solvents used for the hole injection layer, the hole transport layer, the light emitting layer, and the electron transport layer, when the hole transport layer has the highest solvent boiling point, after coating the hole transport layer, the cathode Is a method of batch heat treatment under the condition of the above formula (a) until the formation of, and when the boiling point of the solvent contained in the light emitting layer forming coating solution is the highest, after the light emitting layer is coated, A batch heat treatment is performed under the conditions satisfying the above-described formula (a) until the cathode is formed.

  In the present invention, the step of performing the batch heat treatment at the heat treatment temperature defined by the above formula (a) is performed after the final organic layer, for example, the electron injection layer is formed and before the cathode is formed. It is a preferable aspect that it is a process.

The production method of the organic EL element according to the first production method will be described more specifically.
(1): For example, a polyethylene terephthalate film (hereinafter abbreviated as PET, Tg: 110 ° C.) is used as a resin film substrate, and a gas barrier layer having an elemental composition profile defined in the present invention is formed thereon with a magnetic field. A gas barrier film is produced by a discharge plasma chemical vapor deposition method having a discharge space between the rollers having the above.

  (2): Next, after forming an anode by a known method, a hole injection layer is formed using a coating solution for forming a hole injection layer containing solvent A, and then naturally dried.

  (3): Next, a hole transport layer is formed using a coating liquid for forming a hole transport layer containing the solvent B, and then naturally dried.

  (4): Next, a light emitting layer is formed using a light emitting layer forming coating solution containing the solvent C, and then naturally dried.

  (5): Finally, an electron transport layer is formed using a coating liquid for forming an electron transport layer containing the solvent D.

  (6): Next, among the solvents A to D used in the formation of each organic layer, which is the condition defined by the formula (a), the boiling point of the solvent having the highest boiling point, based on the boiling point of the solvent having the highest boiling point. It is a method characterized by performing a single heat treatment at a temperature range of −10 ° C. or more and Tg + 20 ° C. of the resin film substrate and the above-mentioned PET in the temperature range of 110 ° C. + 20 ° C. = 130 ° C. or less. is there.

  That is, in the present invention, the lower limit of the heat treatment temperature is from the boiling point of the solvent having the highest boiling point among the solvents used for forming the hole injection layer, the hole transport layer, the light emitting layer, and the electron transport layer. The upper limit is a temperature 20 ° C. higher than the glass transition temperature (Tg) of the transparent resin film substrate used. That is, even when heat treatment is performed after formation of any layer, the upper limit of the heating temperature does not exceed the glass transition temperature (Tg) + 20 ° C. of the transparent resin film substrate used.

  The heating time when the heat treatment is performed under the condition of the above formula (a) varies depending on the heating temperature to be applied and cannot be defined uniformly, but is generally in the range of 10 to 120 minutes, In consideration of productivity, it is preferably within a range of 15 to 80 minutes, and more preferably within a range of 15 to 60 minutes.

  The second method of the method for producing an organic EL device of the present invention is to apply each organic layer coating solution prepared by dissolving each forming material of a hole injection layer, a hole transport layer, a light emitting layer and an electron transport layer in a solvent. When sequentially applying, after applying each of the hole injection layer, the hole transport layer, the light emitting layer, and the electron transport layer, heat treatment is performed at the heat treatment temperature defined by the following formula (b). This is a featured manufacturing method.

Formula (b): (boiling point of the solvent constituting the organic layer-forming coating solution−10 ° C.) ≦ (heat treatment temperature) ≦ (glass transition temperature (Tg) + 20 ° C. of transparent resin film substrate)
In the present invention, after each organic layer is applied and formed, heat treatment is performed each time under the heat treatment temperature condition defined by the above formula (b). Therefore, in this manufacturing method, heat treatment is performed at the same number as the number of organic layers at the heat treatment temperature defined by the formula (b).

  When the organic layer contains a plurality of types of solvents, the “boiling point of the solvent constituting the coating liquid for forming an organic layer” is the boiling point of the solvent having the highest boiling point among them.

A method for producing an organic EL element according to the second production method defined by the above formula (b) will be specifically described.
(1): For example, a polyethylene terephthalate film (abbreviated as PET, Tg: 110 ° C.) is used as a transparent resin film base material, and a gas barrier layer having an elemental composition profile defined in the present invention is applied thereon with a magnetic field. A gas barrier film is produced by a discharge plasma chemical vapor deposition method having a discharge space between the rollers.

  (2): Next, after forming the anode by a known method, after forming the hole injection layer using the hole injection layer forming coating solution containing the solvent A as the first step, the formula (b) The first heat treatment is performed at a temperature equal to or higher than (boiling point of solvent A—10 ° C.) and (Tg + 20 ° C. of resin film substrate).

  (3): Next, after forming the hole transport layer using the coating liquid for forming the hole transport layer containing the solvent B, the condition of the formula (b) is satisfied (boiling point of the solvent B −10 ° C.) or more. And, the second heat treatment is performed in a temperature range of (resin film substrate Tg + 20 ° C.) or less.

  (4): Next, after forming the light emitting layer using the light emitting layer forming coating solution containing the solvent C, at a temperature equal to or higher than the condition of the formula (b) (boiling point of the solvent C—10 ° C.) and (Tg + 20 ° C. of resin film substrate) The third heat treatment is performed in the temperature range below.

  (5): Finally, after forming the electron transport layer using the electron transport layer forming coating solution containing the solvent D, the temperature equal to or higher than the condition (b) of the solvent D (boiling point −10 ° C.). And the fourth heat treatment is performed in a temperature range of (resin film substrate Tg + 20 ° C.) or less.

  In the case where the organic layer contains a plurality of kinds of solvents, the “solvent that defines the boiling point of the solvent constituting the coating solution for forming an organic layer” in the present invention means the highest boiling point among them. It has a solvent.

  The heating time when the heat treatment is performed under the condition of the above formula (b) cannot be generally defined by the heating temperature to be applied, but is generally in the range of 10 to 120 minutes. Within the range of -80 minutes is preferable, More preferably, it is within the range of 15-60 minutes.

  Also in the said 2nd manufacturing method, the upper limit of the heat processing temperature given after formation of each organic layer is the temperature of glass transition temperature (Tg) +20 degreeC of the transparent resin film base material currently used. That is, in the present invention, the upper limit temperature of any heat treatment does not exceed the glass transition temperature (Tg) + 20 ° C. of the transparent resin film substrate used.

  In the present invention, each organic layer including a hole injection layer, a hole transport layer, a light-emitting layer, and an electron transport layer is formed by sequentially applying each coating solution prepared by dissolving the formation material of each organic layer in a solvent. Although it is formed, the forming method is not particularly limited. For example, spin coating method, casting method, die coating method, blade coating method, roller coating method, ink jet method, printing method, spray coating method, curtain coating method, LB (A Langmuir-Blodgett method) and the like are preferable, and a die coating method using a slit die coater is more preferable from the viewpoint of productivity.

  Also, the heat treatment method is not particularly limited, but a method of heating by passing through a high temperature environment, a method of heating a substrate having an organic layer by heat conduction by contacting the substrate with a heating element such as a heat block, etc. And a method of heating the atmosphere with an external heater such as a resistance wire, a method using light in the infrared region such as an IR heater, and the like. In particular, a heat treatment method under reduced pressure is preferable in order to effectively remove the solvent. Moreover, when heating a base material, it is preferable to heat from the base material side. Furthermore, the start timing of heating is not particularly limited, but it is preferable to start the heat treatment within one hour after the coating liquid is applied on the substrate. The heating time is preferably in the range of 1 second to 10 hours, and more preferably in the range of 10 seconds to 1 hour.

[Sealing material]
As a sealing material applicable to the sealing of the organic EL element according to the present invention, it is preferable to use a flexible member, and the flexible member preferably has a gas barrier layer on a resin film. . As a characteristic of the gas barrier layer, the water vapor transmission rate is 0.01 g / m ² · day in consideration of crystallization of the organic layer, generation of dark spots due to peeling of the electrode and the like, and extension of the lifetime of the organic EL element. The following is preferable. The water vapor transmission rate is a value measured mainly by the MOCON method by a method based on the JIS K7129B method (1992).

The oxygen permeability is 0.01 ml / m ² · day · atm or less in consideration of crystallization of the organic layer, generation of dark spots due to peeling of the second electrode, etc., and long life of the organic EL element. Is preferred. The oxygen permeability is a value measured mainly by the MOCON method by a method based on JIS K7126B method (1987).

  The thickness of the flexible member to be used is preferably in the range of 10 to 300 μm in consideration of handling at the time of manufacture, tensile strength, stress cracking resistance of the gas barrier layer, and the like. The thickness is shown as an average value of values obtained by measuring 10 points in the longitudinal direction and the width direction using a micrometer.

  In this invention, there is no limitation in particular as a resin base material which comprises the flexible member, The transparent resin film base material which has the gas barrier layer which concerns on the above-mentioned this invention can also be used.

Examples of the gas barrier layer include an inorganic vapor deposition film and a metal foil. As inorganic vapor deposition films, thin film handbooks p879-p901 (Japan Society for the Promotion of Science), vacuum technology handbooks p502-p509, p612, p810 (Nikkan Kogyo Shimbun), vacuum handbook revised editions p132-p134 (ULVAC Japan Vacuum Technology KK) Inorganic films described in (1). For example, metals such as In, Sn, Pb, Au, Cu, Ag, Al, Ti, Ni, MgO, SiO, SiO ₂ , Al ₂ O ₃ , GeO, NiO, CaO, BaO, Fe ₂ O ₃ , Y ₂ O ₃ , TiO ₂ , Cr ₂ O ₃ , Si _x O _y (x = 1, y = 1.5 to 2.0), Ta ₂ O ₃ , ZrN, SiC, TiC, PSG, Si ₃ N ₄ , SiN Single crystal Si, amorphous Si, W, or the like is used.

  Moreover, as a material of metal foil, metal materials, such as aluminum, copper, and nickel, and alloy materials, such as stainless steel and an aluminum alloy, can be used, but aluminum is preferable in terms of workability and cost. The film thickness is about 1 to 100 μm, preferably about 10 to 50 μm.

  The thickness of the metal sheet to be used is preferably in the range of 20 μm to 2 mm in consideration of handling at the time of manufacture and thinning of the panel. Thickness shows the average value which measured 10 each in the vertical direction and the width direction using the micrometer. The constituent metal is not particularly limited, and examples thereof include metal materials such as aluminum, copper, and nickel, and alloy materials such as stainless steel and aluminum alloy.

  Further, a protective layer or the like may be provided on the gas barrier layer as necessary.

  The resin base material may be a simple substance structure or a composite body made of different resin materials, and can be appropriately selected as necessary. Further, the gas barrier layer may be a single layer or a structure in which two or more layers are laminated, and can be appropriately selected as necessary.

<< Applications of organic EL elements >>
The organic EL element according to the present invention can be used as a display device, a display, and various light sources. Examples of light sources include home lighting, interior lighting, clock and liquid crystal backlights, billboard advertisements, traffic lights, light sources for optical storage media, light sources for electrophotographic copying machines, light sources for optical communication processors, and light sources for optical sensors. Furthermore, it can be used in a wide range of applications such as general household appliances that require a display device, but it can be used effectively as a backlight for a liquid crystal display device combined with a color filter, and as a light source for illumination. it can.

  EXAMPLES 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 "part" or "%" is used in an Example, unless otherwise indicated, "part by mass" or "mass%" is represented.

Example 1
<< Production of organic EL element >>
[Production of Organic EL Element 101]
(Preparation of resin base material)
A biaxially stretched polyethylene terephthalate film (abbreviation: PET, thickness: 125 μm, width: 350 mm, Tg: 110 ° C.) was prepared as a resin substrate. The glass transition temperature Tg of PET was measured using a differential scanning calorimeter DSC220 manufactured by Seiko Denshi Kogyo according to JIS K7121.

(Formation of underlayer)
After applying the UV curable organic / inorganic hybrid hard coat material OPSTARZ7501 manufactured by JSR Co., Ltd. on the easy adhesion surface of the resin base material (PET) with a wire bar under the condition that the layer thickness after drying is 4 μm, After drying for 3 minutes at a drying temperature of 80 ° C., curing was performed at 1.0 J / cm ² as a curing condition using a high-pressure mercury lamp in an air atmosphere to form an underlayer. The maximum cross-sectional height Rt (p) representing the surface roughness at this time was 16 nm.

  The surface roughness is calculated from an uneven sectional curve continuously measured with a detector having a stylus having a minimum tip radius using an AFM (Atomic Force Microscope AFM: manufactured by Digital Instruments), and the minimum tip radius is calculated. Was measured a number of times in a section having a measurement direction of 30 μm, and the average roughness related to the amplitude of fine irregularities was obtained.

(Formation of gas barrier layer (A))
Next, using the inter-roller discharge plasma CVD apparatus having the magnetic field shown in FIG. 2, the surface opposite to the surface on which the base layer is formed (the back surface side) of the resin base material is in contact with the film forming roller. Then, the resin base material was mounted on the apparatus, and the gas barrier layer (A) was formed on the underlayer under the conditions of a thickness of 300 nm under the following film formation conditions (plasma CVD conditions).

<Plasma CVD conditions>
Feed rate of source gas (hexamethyldisiloxane, HMDSO): 50 sccm (Standard Cubic Centimeter per Minute)
Supply amount of oxygen gas (O ₂ ): 500 sccm
Degree of vacuum in the vacuum chamber: 3Pa
Applied power from the power source for plasma generation: 0.8 kW
Frequency of power source for plasma generation: 70 kHz
Resin substrate transport speed: 0.8 m / min
<Measurement of element distribution profile>
For the gas barrier layer (A) thus formed, XPS depth profile measurement was performed under the following conditions, and a silicon distribution curve, an oxygen distribution curve, a carbon distribution curve, and an oxygen carbon distribution at a distance from the surface of the thin film layer in the layer thickness direction. A curve was obtained.

Etching ion species: Argon (Ar ⁺ )
Etching rate (SiO ₂ thermal oxide equivalent value): 0.05 nm / sec
Etching interval (SiO ₂ equivalent value): 10 nm
X-ray photoelectron spectrometer: Model “VG Theta Probe”, manufactured by Thermo Fisher Scientific
Irradiation X-ray: Single crystal spectroscopy AlKα
X-ray spot and size: 800 × 400 μm ellipse Based on each element data thus measured, the carbon distribution curve A and silicon distribution curve B with the distance from the surface of the gas barrier layer (A) as the horizontal axis FIG. 3 shows an oxygen distribution curve C and an oxygen carbon distribution curve D, respectively. As is clear from this result, the obtained carbon distribution curve A has a plurality of distinct extreme values, the difference between the maximum value and the minimum value of the atomic ratio of carbon is 5 at% or more, In addition, in a region of 90% or more of the total thickness of the gas barrier layer, it is confirmed that the silicon atomic ratio, the oxygen atomic ratio, and the carbon atomic ratio satisfy the conditions represented by the formula (A). It was done.

(Preparation of anode)
On the gas barrier layer (A), an ITO film (indium tin oxide) having a thickness of 120 nm was formed by sputtering, and patterned by photolithography to form an anode. The pattern was such that the light emission area was 100 mm square.

(Formation of organic layer)
(A) Formation of hole injection layer The ITO (anode) substrate after patterning was ultrasonically cleaned with isopropyl alcohol, dried with nitrogen gas (oxygen concentration 10 ppm or less, moisture 10 ppm or less), and UV ozone cleaning was performed for 5 minutes. . On this ITO substrate, poly (3,4-ethylenedioxythiophene) -polystyrene sulfonate (abbreviation: PEDOT / PSS, abbreviated as * A in Table 1 and abbreviated as PEDOT / PSS in Table 2 described in Example 2). A coating solution prepared by diluting Baytron P Al 4083 manufactured by Bayer with pure water (boiling point: 100 ° C.) to 70% was applied using a slit die coater (manufactured by ITOCHU Machine Technos Co., Ltd.), and the layer thickness was Formed a 30 nm hole injection layer. The film formation was performed in a nitrogen gas atmosphere. After the application, heat treatment was not carried out, and natural drying was performed.

(B) Formation of hole transport layer Next, a hole transport material compound (H-1, Mw = 80,000 described below) was dissolved in chlorobenzene (boiling point 131 ° C.) at a concentration of 0.5%. The liquid was applied using a slit die coater (supra), and a hole transport layer having a layer thickness of 30 nm was provided. Film formation was performed in a nitrogen gas atmosphere. After the application, heat treatment was not carried out, and natural drying was performed.

(C) Formation of Light-Emitting Layer Next, a light-emitting layer-forming coating solution having the following composition was prepared in a nitrogen gas atmosphere at 20 ° C. (oxygen concentration 0%, water content 10 ppm or less), and similarly a nitrogen gas atmosphere at 20 ° C. A light emitting layer having a layer thickness of 40 nm was formed by natural drying under a slit die coater (described above). After the application, no heat treatment was carried out, and natural drying was performed.

<Preparation of light emitting layer forming coating solution>
Compound a-1 1.42 parts by mass Compound D-66 0.25 parts by mass Compound D-67 0.004 parts by mass Compound D-80 0.004 parts by mass Toluene (boiling point 111 ° C.) 100 parts by mass

(D) Formation of Electron Transport Layer Subsequently, 20 mg of the following compound A was dissolved in 4 ml of 1-butanol (boiling point 117 ° C.), and a coating solution for forming an electron transport layer was formed on the light emitting layer by a slit die coater. The electron transport layer having a layer thickness of 30 nm was formed by applying the above. The application was performed in a nitrogen gas atmosphere.

(E) Heat treatment After the electron transport layer was formed as described above, the heat treatment was performed by holding at 129 ° C for 30 minutes in a nitrogen gas atmosphere.

(F) Formation of electron injection layer and cathode Subsequently, the resin base material formed up to the electron transport layer was attached to a vacuum deposition apparatus without being exposed to the atmosphere. Next, each molybdenum resistance heating boat containing sodium fluoride and potassium fluoride was attached to a vacuum deposition apparatus, the vacuum chamber was depressurized to 4 × 10 ⁻⁵ Pa, and then the boat was energized and heated. Sodium fluoride is formed as a thin film having a thickness of 1 nm on the electron transport layer at 0.02 nm / second, and subsequently potassium fluoride is similarly formed at a thickness of 1.2 on the sodium fluoride at 0.02 nm / second. It vapor-deposited as a 5 nm thin film, and formed the electron injection layer. Subsequently, aluminum was vapor-deposited with a thickness of 100 nm to form a cathode.

(Sealing)
Subsequently, the sealing member was adhered and sealed using a commercially available roller laminating apparatus. As the sealing member, a flexible aluminum foil (manufactured by Toyo Aluminum Co., Ltd.), a polyethylene terephthalate (PET) film (12 μm thick) and an adhesive for dry lamination (two-component reactive type) What was laminated using (urethane adhesive) (adhesive layer thickness 1.5 μm) was used.

  The following thermosetting adhesive as a sealing adhesive was uniformly applied to the aluminum surface at a thickness of 20 μm along the adhesive surface (shiny surface) of the aluminum foil using a dispenser. This was dried under a vacuum of 100 Pa or less for 12 hours. Furthermore, it moved to a nitrogen atmosphere with a dew point temperature of −80 ° C. or lower and an oxygen concentration of 0.8 ppm, took 12 hours or longer and dried, and adjusted the moisture content of the sealing adhesive to 100 ppm or lower.

  As the thermosetting adhesive, an epoxy adhesive mixed with the following constituent materials (A) to (C) was used.

(A) Bisphenol A diglycidyl ether (B) Dicyandiamide (C) Epoxy adduct-based curing accelerator As described above, the sealing substrate is closely attached and arranged so as to cover the joint between the take-out electrode and the electrode lead, Using a pressure roller, as the thickening conditions, the pressure roller temperature was 120 ° C., the pressure was 0.5 MPa, the apparatus speed was 0.3 m / min, and the organic EL element 101 was produced.

[Production of Organic EL Element 102]
In the production of the organic EL element 101, the gas barrier layer (B) was formed in the same manner as the gas barrier layer (B) instead of the gas barrier layer (A). Thus, an organic EL element 102 was produced.

(Formation of gas barrier layer (B))
A gas barrier layer (B) composed of silicon oxide by a reactive sputtering method on a polyethylene terephthalate film having a base layer similar to that used for the production of the organic EL device 101 in a gas atmosphere containing oxygen using a silicon target. ) Was formed. The thickness of the obtained gas barrier layer (B) was 300 nm.

  For the obtained gas barrier layer (B), the XPS depth profile measurement performed for the gas barrier layer (A) was similarly performed, and the silicon distribution curve, oxygen distribution curve at the distance from the surface of the thin film layer in the layer thickness direction, A carbon distribution curve and an oxygen carbon distribution curve were obtained. The obtained silicon distribution curve, oxygen distribution curve, carbon distribution curve and oxygen-carbon distribution curve together with the relationship between the atomic ratio and the etching time as well as the relationship between the atomic ratio and the distance (nm) from the surface of the gas barrier layer. The graph shown is shown in FIG. As is clear from the results shown in FIG. 4, the obtained carbon distribution curve did not have an extreme value and deviated from the conditions (1) and (2) defined in the present invention.

[Production of Organic EL Element 103]
In the production of the organic EL element 101, the organic EL element 103 was produced.

(Formation of gas barrier layer (C))
In accordance with the film forming method described in Example 3 of JP-A-7-178860, a gas barrier layer (C) is formed on a polyethylene terephthalate film having an underlayer similar to that used in the production of the organic EL element 101. Formed. Specifically, as a deposition source, particulate SiO (purity: 99.7%) having a size of about 5 mm is used, and silicon oxide is deposited on the base layer of the resin substrate by EB (Electron Beam) heating deposition. A system (SiOx) gas barrier thin film was formed. A gas barrier layer (C) having a thickness of 300 nm was formed at a film feed rate of 100 m / min and an applied power of 5 kW.

Next, propylene gas was used as a reaction gas, and a high-frequency voltage was applied to an electrode installed in the vicinity of the chill roller in order to advance carbon substitution, so that propylene gas was brought into a plasma state. The flow rate was changed, and the amplitude was changed to 500 V around the excitation voltage of 1 kV, and the sin curve was changed. With respect to the gas barrier layer (C) thus obtained, the amount of carbon substitution and the change in the thickness direction were measured using an ESCA apparatus. As measurement conditions, Mg-Kα rays were used as a light source, the output was 8 kV × 30 mA, and the degree of vacuum was constant 5 × 10 ⁻⁶ Pa.

  The width of the carbon distribution in the thickness direction of the obtained gas barrier layer (C) is in the range of 1.0 to 2.8 at%, and the difference between the maximum extreme value and the minimum extreme value is less than 5 at%, It was outside the condition (2) defined in the present invention.

[Production of Organic EL Element 104]
In the production of the organic EL element 101, the organic EL element 104 was produced in the same manner except that the gas barrier layer (A) was changed to a gas barrier layer (D) formed by the following method.

(Formation of gas barrier layer (D))
Polyethylene having a base layer similar to that used in the production of the organic EL element 101 using PE-CVD (Plasma-Enhanced CVD), which is a method for forming a gas barrier layer described in JP-T-2005-537963. A gas barrier layer (D) having a gradient composition having a thickness of about 300 nm was formed on the terephthalate film.

  A gradient coating consisting of silicon, carbon, oxygen and nitrogen was made using silane (maximum flow rate about 500 sccm / min), ammonia (maximum flow rate about 60 sccm / min) and propylene oxide (maximum flow rate about 500 sccm / min). The rate of reactant gas was varied during deposition such that the composition of the coating changed continuously in its thickness direction. The power supplied to the RF electrode was 100 W when the plasma was generated from propylene oxide, and 200 W when the mixture of silane and ammonia was supplied to the reactor. The vacuum level in the reactor was 26.6 Pa, and the average temperature was about 55 ° C. The silicon distribution, oxygen distribution, carbon distribution, and nitrogen distribution in the thickness direction of the gas barrier layer (D) formed as described above were measured in the same manner as the XPS depth profile measurement performed for the gas barrier layer (A). A silicon distribution curve, an oxygen distribution curve, a carbon distribution curve and a nitrogen distribution curve were obtained.

  As a result of analyzing the obtained distribution curve profile, it is the same element distribution profile as FIG. 4 described in JP 2005-537963 A, where the carbon content is maximized, and the silicon content is the maximum value. The region where the regions to be present are alternately present, and the region in which the ratio of silicon atoms in the gas barrier layer satisfies the formula (A) or the formula (B) defined in the condition (3) of the present invention is less than 90% Met.

[Production of Organic EL Element 105]
In the production of the organic EL element 104, after the electron transport layer was applied and formed, the heat treatment was performed in the same manner except that the heat treatment was performed at 105 ° C. for 30 minutes in a nitrogen gas atmosphere. An EL element 105 was produced.

[Production of organic EL elements 106 to 110]
In the production of the organic EL element 101, after the electron transport layer was applied and formed, the heat treatment was performed under the nitrogen gas atmosphere for 30 minutes under the temperature conditions shown in Table 1 and subjected to the heat treatment. Similarly, organic EL elements 106 to 110 were produced.

[Production of Organic EL Elements 111 to 113]
In the production of the organic EL element 101, the type of the solvent used in the hole transport layer and the heat treatment conditions after coating and forming the electron transport layer were changed to the conditions shown in Table 1 in the same manner. EL elements 111 to 113 were produced.

[Production of Organic EL Element 114]
In the production of the organic EL element 101, an organic EL element 114 was produced in the same manner except that the solvent used for preparing the coating solution for the light emitting layer was changed from toluene to xylene (boiling point: 144 ° C.).

[Production of Organic EL Element 115]
In the production of the organic EL element 111, the resin base material is changed from PET to a biaxially stretched polyethylene naphthalate film (PEN film, thickness: 125 μm, width: 350 mm, Tg: 155 ° C.), and an electron transport layer Then, an organic EL element 115 was produced in the same manner except that a heat treatment was performed at 135 ° C. for 30 minutes in a nitrogen gas atmosphere.

[Production of organic EL elements 116 to 118]
In the production of the organic EL element 115, after the electron transport layer was applied and formed, the heat treatment condition was maintained under the nitrogen gas atmosphere for 30 minutes under the temperature conditions shown in Table 1, except that each heat treatment was performed. In the same manner, organic EL elements 116 to 118 were produced.

[Production of Organic EL Element 119]
In the production of the organic EL element 118, the type of the solvent used in the light emitting layer and the heat treatment conditions after coating and forming the electron transport layer were similarly changed to the conditions shown in Table 1, and the organic EL element was similarly obtained. 119 was produced.

[Preparation of organic EL elements 120 to 122]
In the production of the organic EL element 117, organic EL elements 120 to 122 were produced in the same manner except that the gas barrier layer (A) was changed to the gas barrier layers (B) to (D), respectively.

[Production of Organic EL Elements 123 and 124]
In the production of the organic EL element 115, after the electron transport layer was applied and formed, the temperature conditions shown in Table 1 were maintained for 30 minutes under a nitrogen gas atmosphere as the heat treatment conditions, respectively, except that the heat treatment was performed. Similarly, organic EL elements 123 and 124 were produced.

  In addition, the detail of each component described with the abbreviation in Table 1 is as follows.

* A: PEDOT / PSS (poly (3,4-ethylenedioxythiophene) -polystyrene sulfonate)
Solvent 1: Chlorobenzene (boiling point: 132 ° C.)
Solvent 2: Toluene (boiling point: 111 ° C.)
Solvent 3: Xylene (boiling point: 144 ° C)
Solvent 4: n-BuOH (boiling point: 118 ° C.)
Solvent 5: n-butyl acetate (boiling point: 126 ° C.)
Solvent 6: Isopropyl acetate (boiling point: 89 ° C.)
Solvent 7: Hexyl chloride (boiling point: 134 ° C)
Solvent 8: cyclohexane (boiling point: 155 ° C.)
<< Evaluation of organic EL elements >>
(Evaluation of luminous efficiency)
Using a spectral radiance meter CS-2000 (manufactured by Konica Minolta), the external extraction quantum efficiency (%) of the organic EL elements 101 to 116 when a ^2.5 mA / cm ² constant current was applied was measured. Based on each measurement result, the external extraction quantum efficiency (%) of the organic EL element 101 was displayed as a relative value of 100. The larger the numerical value, that is, the closer to 100 in Table 2, the better the luminous efficiency which is the external extraction quantum efficiency (%).

(Evaluation of luminous lifetime)
For each organic EL element, continuous light emission was performed under a constant current condition of 10 mA / cm ² in an environment of 23 ° C. and 50% RH, and an initial luminance was obtained using a spectral radiance meter CS-2000 (manufactured by Konica Minolta). The time (half-life: τ _1/2 ) required to reach half the brightness of was measured. In addition, evaluation of the light emission lifetime was displayed by the relative value which sets the half life (time) of the organic EL element 101 to 100. The larger the value, the longer the light emission lifetime.

(Durability evaluation)
Each organic EL element was subjected to a heat treatment for 500 hours in an environment of 85 ° C. and 85% RH, and then the presence or absence of dark spots was visually confirmed on the luminescent image, and the durability was evaluated according to the following criteria. did.

◎: No problem with dark spots ○: Slight generation of small-sized dark spots is observed when observed with a magnifying glass, but cannot be visually observed △: Slightly generated small-sized dark spots Recognized x: Dark spots that can be clearly confirmed visually are generated. Table 2 shows the evaluation results obtained as described above.

  As is clear from the results shown in Table 2, the silicon distribution curve, oxygen distribution curve and carbon distribution curve in the thickness direction of the gas barrier layer satisfy all of the conditions (1) to (3) defined in the present invention. In addition, the organic EL device of the present invention produced by a method satisfying the condition (a) defined in the present invention for the heating condition after coating the organic layer is a dark spot under high temperature and high humidity storage compared to the comparative example. It can be seen that the light emission efficiency and the light emission lifetime are excellent.

Example 2
<< Production of organic EL element >>
[Preparation of Organic EL Elements 201-217]
In the production of the organic EL device 101 described in Example 1, the type of the gas barrier layer and the hole injection layer, the hole transport layer, the light emitting layer, and the electron transport layer were applied and formed, respectively, and then independently shown in Table 3. The organic EL elements 201 to 217 were produced in the same manner except that sequential heat treatment was performed under the heat treatment conditions described in.

<< Evaluation of organic EL elements >>
About the produced said organic EL elements 201-217, it carried out similarly to each evaluation method of the organic EL element as described in Example 1, and evaluated luminous efficiency, luminous lifetime, and durability.

  In addition, about the luminous efficiency and the luminous lifetime, it represented by the relative value when the luminous efficiency and luminous lifetime of the organic EL element 101 produced in Example 1 were set to 100, respectively.

  The results obtained as described above are shown in Table 3.

  As is clear from the results shown in Table 3, the silicon distribution curve, oxygen distribution curve, and carbon distribution curve in the thickness direction of the gas barrier layer, which are constituent conditions of the present invention, are defined by the conditions (1) to (1) to The organic EL device of the present invention produced by the method satisfying all of (3) and satisfying the condition (b) defined in the present invention produces dark spots under high temperature and high humidity storage compared to the comparative example. No light emission efficiency and light emission lifetime.

  The method for producing an organic electroluminescent device of the present invention uses a transparent resin film substrate, is excellent in economic efficiency, suppresses the generation of dark spots, and is a flexible organic electroluminescent having excellent light emission quantum efficiency (light emission luminance) and light emission lifetime. Luminescent elements can be obtained, and these organic electroluminescent elements can be used for display devices, displays, household lighting, interior lighting, backlights for watches and liquid crystals, signboard advertisements, traffic lights, light sources for optical storage media, electrophotographic copying It can be suitably used as a wide light source such as a light source of a machine, a light source of an optical communication processor, a light source of an optical sensor, and a general household appliance requiring a display device.

DESCRIPTION OF SYMBOLS 1 Transparent resin film base material 2 Gas barrier layer 3 1st electrode (anode)
4 Organic layer unit 5 Second electrode (cathode)
6 Sealing member 7 Opposite film 11 Delivery roller 21, 22, 23, 24 Transport roller 31, 32 Film forming roller 41 Gas supply pipe 51 Power source for plasma generation 61, 62 Magnetic field generator 71 Winding roller A Carbon distribution curve B Silicon Distribution curve C Oxygen distribution curve D Oxygen carbon distribution curve F Gas barrier film EL Organic EL element

Claims (6)

It is composed of a gas barrier layer containing carbon atoms, silicon atoms and oxygen atoms on a transparent resin film substrate, an anode and a cathode, and a plurality of organic layers including at least a light emitting layer between the anode and the cathode. A method for producing an organic electroluminescent element having an organic layer unit comprising:
The gas barrier layer is based on the element distribution measurement in the depth direction by X-ray photoelectron spectroscopy, and the distance from the surface in the layer thickness direction of the gas barrier layer and the total amount of silicon atoms, oxygen atoms and carbon atoms (100 at. %), The ratio of the amount of silicon atoms (referred to as “silicon atom ratio (at%)”), the ratio of the amount of oxygen atoms (referred to as “oxygen atom ratio (at%)”), and the ratio of the amount of carbon atoms (Referred to as “carbon atom ratio (at%)”) A silicon distribution curve, an oxygen distribution curve and a carbon distribution curve satisfying the following conditions (1) to (3):
And after the organic layer unit forms the organic layer containing a solvent by apply | coating each organic layer coating liquid prepared by melt | dissolving the formation material of each organic layer in a solvent, it is until it forms the said cathode. In the process of
Forming the organic layer by batch heat treatment within the range of the heat treatment temperature defined by the following formula (a);
Or, within the range of the heat treatment temperature specified by the following formula (b), each time the organic layer is formed, it is formed by sequential heat treatment,
The manufacturing method of the organic electroluminescent element characterized by these.
(1) In the gas barrier layer, the composition of each atom continuously changes in the layer thickness direction, and the carbon distribution curve has an extreme value.
(2) The difference between the maximum extreme value and the minimum extreme value of the carbon atom ratio is 5 at% or more.
(3) In a region of 90% or more of the total thickness of the gas barrier layer, the atomic ratio (at%) of each atom to the total amount (100 at%) of silicon atoms, oxygen atoms and carbon atoms is expressed by the following formula (A ) Or (B).
Formula (A): (carbon atom ratio) <(silicon atom ratio) <(oxygen atom ratio)
Formula (B): (oxygen atom ratio) <(silicon atom ratio) <(carbon atom ratio)
Formula (a): (The boiling point of the solvent having the highest boiling point among the solvents used for forming the organic layer −10 ° C.) ≦ (heat treatment temperature) ≦ (glass transition temperature (Tg) of the transparent resin film substrate + 20 ° C. )
Formula (b): (boiling point of the solvent constituting the coating solution for forming the organic layer −10 ° C.) ≦ (heat treatment temperature) ≦ (glass transition temperature (Tg) + 20 ° C. of the transparent resin film substrate)   The step of collectively heat-treating the organic layer within the range of the heat treatment temperature defined by the formula (a) is a step after forming the final organic layer and before forming the cathode. The manufacturing method of the organic electroluminescent element of Claim 1 characterized by the above-mentioned.   The method for producing an organic electroluminescent element according to claim 1, wherein the organic layer unit is composed of at least a hole injection layer, a hole transport layer, a light emitting layer, and an electron transport layer.   The organic light-emitting device according to any one of claims 1 to 3, wherein the light-emitting layer contains a light-emitting host compound having a molecular weight of 2000 or less and a light-emitting dopant having a molecular weight of 2000 or less. Production method.   The gas barrier layer is formed using a discharge plasma chemical vapor deposition apparatus that uses a source gas containing an organic silicon compound and oxygen gas to form a discharge space between film forming rollers having opposing magnetic fields. The manufacturing method of the organic electroluminescent element as described in any one of Claim 1- Claim 4.   The said transparent resin film base material is the polyethylene terephthalate film or polyethylene naphthalate film by which biaxial stretching was carried out, The manufacture of the organic electroluminescent element as described in any one of Claim 1-5 characterized by the above-mentioned. Method.

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