JP5267467B2 - Barrier film, method for producing barrier film, organic photoelectric conversion element having barrier film, and solar cell having the element - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a barrier film which has high productivity and can attain extremely high gas barrier performance and high durability and to provide a method for producing the barrier film, an organic photoelectric conversion element obtained by using the barrier film, and a solar cell obtained by using the element. <P>SOLUTION: The method for producing the barrier film comprises the steps of: applying a coating liquid containing polysilazane to the surface of a base material to form a coating film; drying the coating film; irradiating the dried coating film with vacuum ultraviolet light; and modifying the irradiated coating film to form a barrier layer, and further comprises a step of treating the surface of the dried coating film between the step of drying the coating film and the completion of the step of irradiating the dried coating film with vacuum ultraviolet light. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

  The present invention mainly relates to a barrier film used for a display material such as a package of an electronic device or a plastic substrate such as an organic EL element, a solar battery, and a liquid crystal, a method for producing the barrier film, and an organic photoelectric device using the barrier film. The present invention relates to a conversion element and a solar cell.

  Conventionally, a barrier film in which a thin film of a metal oxide such as aluminum oxide, magnesium oxide, or silicon oxide is formed on the surface of a plastic substrate or film is used for packaging an article, food, or the like that needs to block various gases such as water vapor and oxygen. Widely used in packaging applications to prevent alteration of industrial products and pharmaceuticals.

  In addition to packaging applications, it is used in liquid crystal display elements, solar cells, organic electroluminescence (EL) substrates, and the like.

  As a method for forming such a barrier film, a chemical volume method (plasma CVD) in which a film is formed on a substrate while being oxidized with oxygen plasma under reduced pressure using an organic silicon compound typified by TEOS (tetraethoxysilane), A sputtering method is known in which metal Si is evaporated using a semiconductor laser and deposited on a substrate in the presence of oxygen.

Since these methods can form a thin film with an accurate composition on a substrate, they have been preferably used for the formation of metal oxide thin films including SiO _2. It took a lot of time, the continuous production was difficult, the equipment was enlarged, and the productivity was remarkably bad.

  In order to solve such problems, for the purpose of improving productivity, a silicon-containing compound is applied, a method of forming a silicon oxide thin film by modifying the coating film, and the same CVD method generates plasma at atmospheric pressure. Attempts to generate films under atmospheric pressure have been made and are being studied for barrier films.

  As a silicon oxide film that can be generally produced by a solution process, a technique of forming an alkoxide compound as a raw material by a method called a sol-gel method is known. This sol-gel method generally requires heating to a high temperature, and further, a large volume shrinkage occurs in the course of the dehydration condensation reaction, resulting in a large number of defects in the film.

  In order to prevent this, a method of mixing organic substances that do not directly participate in oxide formation into the raw material solution has been found, but there is a concern that these organic substances may remain in the film and thus the barrier property of the entire film may be lowered. Has been. For these reasons, it has been difficult to directly use an oxide film produced by a sol-gel method as a protective film of a flexible electronic device.

  As another method, it has been proposed to produce silicon oxide using a silazane compound having a basic structure of silazane structure (Si-N) as a raw material. In this case, the reaction is not from dehydration condensation polymerization but from nitrogen to oxygen. Since this is a direct substitution reaction, it is known that a dense film having a large mass yield before and after the reaction of 80% to 100% or more and few defects in the film due to volume shrinkage can be obtained.

  However, the production of a silicon oxide thin film by substitution reaction of a silazane compound requires a high temperature of 450 ° C. or higher, and it was impossible to adapt to a flexible substrate such as plastic.

  As a means for solving such a problem, it is described in the following publication that the heating temperature at the time of forming the silica coating can be reduced and the heating time can be shortened by irradiating the coating of polysilazane with ultraviolet rays (for example, (See Patent Document 1).

  Furthermore, in order to lower the temperature of ceramization and obtain a good gas barrier film applied to a plastic film, a technique using a catalyst is disclosed (for example, see Patent Document 2).

However, in the method for forming a coating film containing polysilazane on the surface of the base material and forming a ceramic film substantially composed of SiO ₂ by ceramicizing the coating film, in order to reduce the temperature required for the ceramic conversion Although it is characterized by including a step of irradiating ultraviolet rays such as a high-pressure mercury lamp using a catalyst, it cannot be said that improvement in reforming efficiency is sufficient.

  As a response to the above-mentioned problems, the atomic quantum bond is formed by using light energy of 100 nm to 200 nm called vacuum ultraviolet light (hereinafter also referred to as VUV or VUV light) larger than the interatomic bonding force in the silazane compound. There has been proposed a method of forming a silicon oxide film at a relatively low temperature by causing an oxidation reaction with active oxygen or ozone to proceed while cutting directly by the action of only photons called.

  A technique is disclosed in which a polysilazane film is formed by a wet method, and the polysilazane film is modified into a silicon oxide thin film by irradiation with VUV light having a wavelength of 150 nm to 200 nm to form a barrier layer (see, for example, Patent Document 3). .)

  However, because of the high reactivity of vacuum ultraviolet light, substances existing between the vacuum ultraviolet light source and the polysilazane film, for example, oxygen gas in the space existing in the optical path, or organic substances attached to the surface of the polysilazane film Dust, adsorbed water and oxygen molecules, or coating solvent remaining on the surface of the polysilazane film also absorbs vacuum ultraviolet light, so it is necessary for the original silazane compound to absorb and form a silicon oxide film. You will be deprived of energy. Thus, it is not mentioned that the presence of impurities on the surface after coating and drying hinders efficient modification, and as a result, good gas barrier properties cannot be efficiently achieved.

Japanese Patent Laid-Open No. 5-105486 Japanese Patent Laid-Open No. 10-279362 Special table 2009-503157

  An object of the present invention is to provide a barrier film capable of achieving high productivity and extremely high gas barrier performance and high durability, a method for producing the barrier film, an organic photoelectric conversion element using the barrier film, and a solar cell using the element. It is to be.

  The above object of the present invention has been achieved by the following constitution.

1. After the step of applying a coating liquid containing polysilazane on the surface of the substrate to prepare a coating film, the step of drying the coating film, and the step of irradiating the coating film with vacuum ultraviolet light, the coating film In the method for producing a barrier film having a step of forming a barrier layer by modifying
After the step of drying the coating film , and before the step of irradiating the vacuum ultraviolet light and at least one of the step of irradiating the vacuum ultraviolet light, the step of performing a surface treatment,
Step of performing the surface treatment, a manufacturing method of the barrier film, wherein step der Rukoto blowing gas mainly containing gas which does not absorb vacuum ultraviolet light to the coating film.

2. 2. The method for producing a barrier film according to 1 above, wherein the content of the gas that does not absorb the vacuum ultraviolet light in the gas is 95% by volume or more.

3. 3. The method for producing a barrier film as described in 2 above, wherein the content of the gas that does not absorb the vacuum ultraviolet light in the gas is 99% by volume or more.

4). 4. The method for producing a barrier film as described in 3 above, wherein the content of the gas that does not absorb the vacuum ultraviolet light in the gas is 100% by volume.

5. 5. The method for producing a barrier film according to any one of 1 to 4, wherein the gas that does not absorb vacuum ultraviolet light is nitrogen.

6 . 6. The method for producing a barrier film according to any one of 1 to 5 , wherein the vacuum ultraviolet light is irradiation light from a xenon excimer lamp.

7 . A barrier film produced by the method for producing a barrier film according to any one of 1 to 6 above.

8 . 8. An organic photoelectric conversion element comprising the barrier film described in 7 above.

9 . 9. A solar cell comprising the organic photoelectric conversion element as described in 8 above.

  According to the present invention, there are provided a barrier film capable of achieving high productivity and extremely high gas barrier performance and high durability, a method for producing the barrier film, an organic photoelectric conversion element using the barrier film, and a solar cell using the element. I was able to.

  The barrier film manufacturing method of the present invention has a gas barrier film that has higher productivity and can achieve extremely high gas barrier performance and high durability than the structure described in any one of claims 1 to 8. A film manufacturing method could be provided.

  Moreover, the barrier film produced using the manufacturing method of the barrier film of this invention, the organic photoelectric conversion element which has this film, and the solar cell using this element were able to be provided.

  Hereinafter, the present invention, its components, and embodiments for carrying out the present invention will be described in detail.

<< Barrier film manufacturing method and barrier film >>
The manufacturing method of the barrier film of this invention and the barrier film of this invention manufactured by this manufacturing method are demonstrated.

  The method for producing a barrier film of the present invention comprises a step of applying a coating liquid containing polysilazane on the surface of a substrate to prepare a coating film, a step of drying the coating film, and then applying vacuum ultraviolet light to the coating film. In the method for producing a barrier film having the step of forming the barrier layer by modifying the coating film through the step of irradiating the film, between the step of drying the coating film and the step of irradiating the vacuum ultraviolet light By providing the step of performing the surface treatment, a method for producing a barrier film having high productivity and extremely high gas barrier performance is provided.

  As one aspect of the method for producing a barrier film of the present invention, a resin film substrate such as polyethylene terephthalate (PET) is used as a base material, and a coating film containing one or more polysilazanes on at least one side of the PET (polysilazane) A barrier layer that expresses a gas barrier property (also referred to as barrier performance) by applying a modification treatment, and the barrier layer is coated with the polysilazane-containing layer. The surface treatment is performed at any timing between the drying step and the coating film is modified by vacuum ultraviolet (VUV).

  In addition, it is a more preferable aspect that the step of performing the surface treatment is performed immediately after drying or simultaneously with the coating film being reformed by vacuum ultraviolet (VUV).

  The barrier layer may be a single layer (a layer that can be formed by one coating) or a plurality of similar layers, and the plurality of layers can further improve the gas barrier property. In the present specification, the laminated structure is not particularly illustrated, but the laminated structure can also be preferably used in order to achieve higher gas barrier properties by using the effects of the present invention.

<< Step of surface treatment >>
The step of performing the surface treatment according to the method for producing a barrier film of the present invention will be described.

  The surface treatment according to the present invention is a residual solvent, a raw material or a coating solvent existing in the surface of the coating film containing polysilazane (polysilazane-containing layer) or in the coating film, and further in the preparation, coating and drying steps of the coating liquid. Vacuum ultraviolet rays (VUV) used during coating modification, such as dust and impurities mixed in, foreign matter, additives such as catalysts for promoting reaction during heating and drying, oxygen molecules adsorbed on the surface of the barrier layer, water molecules, etc. The purpose is to reduce and remove substances other than polysilazane compounds.

  As a specific means of surface treatment according to the present invention, for example, oxygen in the air is activated by using ultraviolet light having a longer wavelength and absorbing oxygen than vacuum ultraviolet light (VUV) such as a low-pressure mercury lamp. Aside from the so-called UV ozone treatment that removes organic matter by oxidation, or a drying process, the remaining coating solvent and adsorbed water molecules are vaporized and removed by irradiating infrared rays or the like, or there is no absorption to vacuum ultraviolet rays (VUV). By exposing to gas, unnecessary molecules adsorbed on the surface can be replaced and removed, and surface treatment by corona discharge or plasma discharge can be used.

  Among these, from the viewpoint of apparatus cost, running cost, and efficiency, UV ozone treatment, infrared treatment, and exposure to a gas mainly containing a gas that does not absorb vacuum ultraviolet light are preferable.

  Of course, the above-mentioned surface treatment effect can be obtained even with vacuum ultraviolet (VUV), but the cost of the apparatus is expensive, and it is necessary to control the oxygen concentration at the time of irradiation and to maintain the irradiation distance stably. In the surface treatment, it is preferable to use the above-described method that requires little such management and that can be carried out simultaneously with the step of reforming by irradiation with vacuum ultraviolet rays (VUV) (also called the reforming step). .

  In the case of UV ozone treatment, from the viewpoint of improving the generation efficiency of active oxygen and improving the arrival of active oxygen to the treatment surface, the oxygen concentration during irradiation is 21% by volume or less, which is the oxygen concentration in ordinary air, Irradiation at 1% by volume or more is preferred.

  The irradiation distance is preferably in the range of 5 mm to 200 mm from the viewpoint of preventing thermal damage to the surface of the base material and maintaining appropriate light intensity.

  In the case of infrared heating, it is preferable that the surface of the polysilazane coating film can be heated to 70 ° C. or higher and 150 ° C. or lower from the viewpoint of performing an appropriate surface treatment and not causing thermal damage to the substrate.

  As a method for replacing and removing unnecessary molecules adsorbed on the surface, a preferred embodiment is that the coated and dried polysilazane coating is in an environment where it is replaced with dry nitrogen so as to be lower than the oxygen concentration in the air. How to expose.

  In this case, the nitrogen gas substitution rate of air is 95% by volume or more, more preferably 99% by volume or more, more preferably 99% by volume or more in terms of nitrogen gas concentration. Further, under a reduced atmosphere, dry nitrogen gas is sprayed directly onto the surface of the polysilazane coating film after coating and drying.

  By doing so, the vacuum ultraviolet (VUV) absorbing component adhering to and adsorbing to the surface of the polysilazane coating film can be forcibly removed.

  As long as the effect of the surface treatment according to the present invention can be achieved, the above-mentioned surface treatment means can be applied alone or in combination.

The corona discharge treatment is a treatment condition that is usually used, for example, a distance of 0.2 mm to 5 mm between the electrode tip and the base fabric to be treated, and the treatment amount is 10 W · min or more per 1 m ² , preferably A range of 10 W · min to 200 W · min is preferable, and a range of 20 W · min to 180 W · min is more preferable.

  The plasma treatment step is performed by using a single gas such as argon, helium, krypton, neon, xenon, hydrogen, nitrogen, oxygen, ozone, carbon monoxide, carbon dioxide, sulfur dioxide, or a mixed gas thereof, for example, an oxygen concentration of 5% by volume to A mixed gas of oxygen and nitrogen containing 15% by volume can be implemented by applying a voltage between the counter electrodes to generate plasma discharge.

  As the plasma treatment conditions, for example, the distance between the electrodes through which the substrate to be treated passes is appropriately determined according to the thickness of the substrate, the magnitude of the applied voltage, the flow rate of the mixed gas, etc. The range of ˜20 mm is preferable, and the range of 0.2 mm to 10 mm is more preferable. The voltage applied between the electrodes is applied so that the electric field strength when applied is 1 kV / cm to 40 kV / cm. Preferably, the frequency of the AC power source at that time is preferably in the range of 1 kHz to 100 kHz, and more preferably in the range of 1 kHz to 100 kHz.

  The corona discharge treatment and the plasma treatment according to the present invention are effective for cleaning the surface of the polysilazane layer (polysilazane film) by being carried out under the above treatment conditions, and prevent discharge damage to the surface of the polysilazane film. Thus, discharge damage of the polysilazane layer can be prevented, and a barrier layer with high smoothness can be produced.

  An organic photoelectric conversion element having a barrier film having a barrier layer with good surface smoothness, a solar cell having the element, etc. are excellent in energy conversion efficiency and exhibit good energy conversion efficiency even after aging under forced deterioration conditions. .

  The surface smoothness of the barrier layer is preferably the surface roughness specified by JIS B 0601, and the maximum cross-sectional height Rt (p) is preferably 30 nm or less.

  Specifically, the surface roughness is calculated from the cross-sectional curve of the unevenness measured continuously with a detector having a stylus with a minimum tip radius using an AFM (Atomic Force Microscope), and measured with a stylus with a minimum tip radius. This is the roughness related to the amplitude of fine irregularities, measured many times in a section whose direction is several tens of μm.

(Modification treatment of coating film containing polysilazane using vacuum ultraviolet ray (VUV))
The barrier layer according to the present invention is modified by a method of irradiating a coating film containing polysilazane with vacuum ultraviolet rays (VUV) after coating a solution containing polysilazane on a substrate.

  The barrier layer according to the present invention is a modified film formed by applying a polysilazane-containing solution onto a substrate and drying, and then subjecting the coating film containing polysilazane to the above-described surface treatment step or simultaneously irradiating with vacuum ultraviolet rays. That is, a barrier layer is formed.

  By this vacuum ultraviolet ray (VUV light) irradiation, the molecular bond of polysilazane can be broken, and even a small amount of oxygen in the film or atmosphere can be efficiently converted into ozone or active oxygen. Ceramicization (silica modification) is promoted, and the resulting ceramic film becomes denser. VUV light irradiation is effective at any time point after the coating film is formed.

  Specifically, vacuum ultraviolet rays (VUV light) of 100 nm to 200 nm are preferably used as the vacuum ultraviolet rays according to the present invention.

In the irradiation with vacuum ultraviolet rays, the irradiation intensity and / or the irradiation time are set within a range in which the substrate carrying the irradiated coating film is not damaged. Taking the case of using a plastic film as a base material as an example, the base material so that the intensity of the base material surface is ^{10mW / cm 2 ~300mW / cm 2} - sets the ramp distance, 0.1 second to 10 It is preferable to perform irradiation for a minute, preferably 0.5 seconds to 3 minutes.

  As the vacuum ultraviolet irradiation apparatus, a commercially available lamp (for example, manufactured by USHIO INC.) Can be used.

  Vacuum ultraviolet (VUV) irradiation can be applied to both batch processing and continuous processing, and can be appropriately selected depending on the shape of the substrate to be coated.

  For example, in the case of batch processing, a substrate (eg, silicon wafer) having a polysilazane coating film on the surface can be processed in a vacuum ultraviolet ray baking furnace equipped with a vacuum ultraviolet ray source. The vacuum ultraviolet baking furnace itself is generally known, and for example, Ushio Electric Co., Ltd. can be used. In addition, when the base material having a polysilazane coating film on the surface is in the form of a long film, vacuum ultraviolet rays are continuously irradiated in the drying zone equipped with the vacuum ultraviolet ray generation source as described above while being conveyed. Can be made into ceramics.

  Since the vacuum ultraviolet light is larger than the interatomic bonding force of most substances, it can be preferably used because the bonding of atoms can be cut directly by the action of only photons called photon processes. By using this action, the reforming process can be efficiently performed at a low temperature without requiring hydrolysis.

  As a vacuum ultraviolet light source required for this, a rare gas excimer lamp is preferably used.

1. Excimer light emission is called an inert gas because atoms of rare gases such as Xe, Kr, Ar, and Ne do not form a molecule by chemically bonding. However, noble gas atoms (excited atoms) that have gained energy by discharge or the like can be combined with other atoms to form molecules. When the rare gas is xenon,
e + Xe → Xe ^*
Xe ^* + 2Xe → Xe ₂ ^* + Xe
Xe ₂ ^* → Xe + Xe + hν (172 nm)
Thus, when the excited excimer molecule Xe ₂ ^* transitions to the ground state, excimer light of 172 nm is emitted. A feature of the excimer lamp is that the radiation is concentrated on one wavelength, and since only the necessary light is not emitted, the efficiency is high.

  Moreover, since extra light is not radiated | emitted, the temperature of a target object can be kept low.

  Furthermore, since no time is required for starting and restarting, instantaneous lighting and blinking are possible.

  In order to obtain excimer light emission, a method using dielectric barrier discharge is known. Dielectric barrier discharge refers to lightning generated in a gas space by arranging a gas space between both electrodes via a dielectric (transparent quartz in the case of an excimer lamp) and applying a high frequency high voltage of several tens of kHz to the electrode. When the micro discharge streamer reaches the tube wall (dielectric) in a similar very thin discharge called micro discharge, the electric charge accumulates on the dielectric surface, and the micro discharge disappears.

  This micro discharge spreads over the entire tube wall, and is a discharge that is repeatedly generated and extinguished. For this reason, flickering of light that can be seen with the naked eye occurs. Moreover, since a very high temperature streamer reaches a pipe wall directly locally, there is a possibility that deterioration of the pipe wall may be accelerated.

  As a method for efficiently obtaining excimer light emission, electrodeless field discharge can be used in addition to dielectric barrier discharge.

  Electrodeless electric field discharge by capacitive coupling, also called RF discharge. The lamp and electrodes and their arrangement may be basically the same as for dielectric barrier discharge, but the high frequency applied between the two electrodes is lit at several MHz. Since the electrodeless field discharge can provide a spatially and temporally uniform discharge in this way, a long-life lamp without flickering can be obtained.

  In the case of dielectric barrier discharge, micro discharge occurs only between the electrodes, so the outer electrode covers the entire outer surface and allows light to pass through in order to extract light to the outside in order to discharge in the entire discharge space. Must.

  For this reason, an electrode in which a fine metal wire is formed in a net shape is used. Since this electrode uses as thin a line as possible so as not to block light, it is easily damaged by ozone generated by vacuum ultraviolet light in an oxygen atmosphere.

  In order to prevent this, it is necessary to provide an atmosphere of an inert gas such as nitrogen around the lamp, that is, the inside of the irradiation apparatus, and provide a synthetic quartz window to extract the irradiation light. Synthetic quartz windows are not only expensive consumables, but also cause light loss.

  Since the double cylindrical lamp has an outer diameter of about 25 mm, the difference in distance to the irradiation surface cannot be ignored between the position directly below the lamp axis and the side surface of the lamp, resulting in a large difference in illuminance. Therefore, even if the lamps are arranged in close contact, a uniform illuminance distribution cannot be obtained. If the irradiation device is provided with a synthetic quartz window, the distance in the oxygen atmosphere can be made uniform, and a uniform illuminance distribution can be obtained.

  When electrodeless field discharge is used, it is not necessary to make the external electrodes mesh. The glow discharge spreads over the entire discharge space simply by providing an external electrode on a part of the outer surface of the lamp. As the external electrode, an electrode that also serves as a light reflector made of an aluminum block is usually used on the back of the lamp. However, since the outer diameter of the lamp is as large as in the case of the dielectric barrier discharge, synthetic quartz is required to obtain a uniform illuminance distribution.

  The biggest feature of the capillary excimer lamp is its simple structure. The quartz tube is closed at both ends, and only gas for excimer light emission is sealed inside.

  The outer diameter of the tube of the thin tube lamp is about 6 nm to 12 mm, and if it is too thick, a high voltage is required for starting.

  As for the form of discharge, either dielectric barrier discharge or electrodeless field discharge can be used. The electrode may have a flat surface in contact with the lamp, but if the shape is matched to the curved surface of the lamp, the lamp can be firmly fixed, and the discharge is more stable when the electrode is in close contact with the lamp. Also, if the curved surface is made into a mirror surface with aluminum, it also becomes a light reflector.

  The Xe excimer lamp is excellent in luminous efficiency because it emits ultraviolet light having a short wavelength of 172 nm at a single wavelength. Since this light has a large oxygen absorption coefficient, radical oxygen atomic species and ozone can be generated at a high concentration with a small amount of oxygen.

  In addition, it is known that the energy of light having a short wavelength of 172 nm for dissociating the bonds of organic substances has high ability.

  Due to the high energy of the active oxygen, ozone and ultraviolet radiation, the polysilazane layer can be modified in a short time.

  Therefore, compared with low-pressure mercury lamps with wavelengths of 185 nm and 254 nm and plasma cleaning, it is possible to shorten the process time associated with high throughput, reduce the equipment area, and irradiate organic materials and plastic substrates that are easily damaged by heat. .

  Since the excimer lamp has high light generation efficiency, it can be lit with low power. In addition, light having a long wavelength that causes a temperature rise due to light is not emitted, and energy is irradiated at a single wavelength in the ultraviolet region, so that the rise in the surface temperature of the object to be fired is suppressed. For this reason, it is suitable for flexible film materials such as PET that are easily affected by heat.

《Vacuum UV irradiation intensity》
If the irradiation intensity is high, the probability that the photons and chemical bonds in the polysilazane collide increases, and the modification reaction can be shortened. Further, since the number of photons penetrating to the inside increases, the modified film thickness can be increased and / or the film quality can be improved (densification).

  However, if the irradiation time is too long, the flatness may be deteriorated and other materials of the barrier film may be damaged. In general, the progress of the reaction is considered by the integrated light quantity expressed by the product of irradiation intensity and irradiation time. The absolute value of intensity may be important.

Therefore, in the present invention, in the vacuum ultraviolet ray (VUV) irradiation step, it is possible to suppress both damage to the base material and damage to the members of the lamp and the lamp unit, increase the reforming efficiency, and improve the gas barrier performance. from at least once it is preferable to perform the modification process which gives the maximum irradiation intensity of ^{100mW / cm 2 ~200mW / cm 2} .

(Vacuum ultraviolet (VUV) irradiation time)
The irradiation time of the vacuum ultraviolet ray (VUV) according to the present invention can be arbitrarily set, but the irradiation time in the high illuminance process is 0. 0 from the viewpoints of substrate damage and film defect generation and gas barrier performance variation. It is preferably 1 second to 3 minutes, and more preferably 0.5 second to 1 minute.

(Oxygen concentration during irradiation with vacuum ultraviolet rays (VUV))
The oxygen concentration at the time of vacuum ultraviolet ray (VUV) irradiation according to the present invention is preferably 500 ppm to 10000 ppm (1%), more preferably 1000 ppm to 5000 ppm.

  By adjusting the oxygen concentration within the above range, it is possible to prevent the formation of an oxygen-excess gas barrier film and to prevent deterioration of gas barrier properties, as will be described later.

  In addition, the air replacement time is prevented from becoming unnecessarily long. At the same time, when continuous production such as roll-to-roll is performed, the amount of air (oxygen) entrained in the vacuum ultraviolet (VUV) irradiation chamber by web transport Increase in the oxygen concentration) and the oxygen concentration cannot be adjusted.

  Further, according to the study by the present inventors, in the polysilazane-containing coating film, oxygen and a small amount of water are mixed at the time of coating, and there are also adsorbed oxygen and adsorbed water on the support other than the coating film, It was found that there are enough oxygen sources to supply oxygen required for the reforming reaction without introducing oxygen into the inside.

  Rather, when the VUV light is irradiated in an atmosphere containing a large amount of oxygen gas (a few percent level), the gas barrier film after the modification has an excessive oxygen structure and the gas barrier properties deteriorate.

  Further, as described above, 172 nm vacuum ultraviolet rays (VUV) are absorbed by oxygen and the amount of light at 172 nm reaching the film surface is reduced, so that the efficiency of the light treatment is likely to be lowered.

  That is, it is preferable to perform the modification treatment in a state where the VUV light efficiently reaches the coating film in a state where the oxygen concentration is as low as possible at the time of vacuum ultraviolet (VUVJ) irradiation.

  This is a significant difference between the method of depositing and producing a film with a composition ratio controlled in advance, such as CVD and the like, and the method of preparing a precursor film by coating and a modification process. This is unique to the application method below.

  As a gas other than oxygen at the time of irradiation with vacuum ultraviolet rays (VUV), a dry inert gas is preferable, and dry nitrogen gas is particularly preferable from the viewpoint of cost. The oxygen concentration can be adjusted by measuring the flow rate of oxygen gas and inert gas introduced into the irradiation chamber and changing the flow rate ratio.

<Coating film containing polysilazane>
The coating film containing polysilazane according to the present invention will be described.

  The polysilazane film according to the present invention is formed by applying a coating solution containing at least one polysilazane compound on a substrate.

  Any appropriate method can be adopted as a coating method. Specific examples include a spin coating method, a roll coating method, a flow coating method, an ink jet method, a spray coating method, a printing method, a dip coating method, a casting film forming method, a bar coating method, and a gravure printing method. The coating thickness can be appropriately set according to the purpose. For example, the coating thickness can be set so that the thickness after drying is preferably about 1 nm to 100 μm, more preferably about 10 nm to 10 μm, and most preferably about 10 nm to 1 μm.

“Polysilazane” used in the present invention is a polymer having a silicon-nitrogen bond, and is composed of Si—N, Si—H, N—H, etc., such as SiO ₂ , Si ₃ N _4, and both intermediate solid solutions SiOxNy, etc. It is a precursor inorganic polymer.

  In order not to damage the film substrate, a compound which is modified to silica which is converted to silica by being ceramicized at a relatively low temperature as described in JP-A-8-112879 is preferable.

—Si (R ₁ ) (R ₂ ) —N (R ₃ ) —
In the formula, R ₁ , R ₂ and R ₃ each represent a hydrogen atom, an alkyl group, an alkenyl group, a cycloalkyl group, an aryl group, an alkylsilyl group, an alkylamino group or an alkoxy group.

In the present invention, perhydropolysilazane in which all of R ₁ , R _2, and R ₃ are hydrogen atoms is particularly preferable from the viewpoint of the denseness as the resulting barrier film.

  On the other hand, the organopolysilazane in which the hydrogen part bonded to Si is partially substituted with an alkyl group or the like has an alkyl group such as a methyl group, so that the adhesion to the base substrate is improved and the polysilazane is hard and brittle. The ceramic film can be toughened, and there is an advantage that generation of cracks can be suppressed even when the film thickness is increased. These perhydropolysilazane and organopolysilazane may be appropriately selected according to the application, and may be used in combination.

  Perhydropolysilazane is presumed to have a linear structure and a ring structure centered on 6- and 8-membered rings. The molecular weight is about 600 to 2000 (polystyrene conversion) in terms of number average molecular weight (Mn), is a liquid or solid substance, and varies depending on the molecular weight. These are marketed in a solution state dissolved in an organic solvent, and the commercially available product can be used as it is as a polysilazane-containing coating solution.

  As another example of polysilazane which is ceramicized at a low temperature, silicon alkoxide-added polysilazane obtained by reacting the polysilazane of the above chemical formula 1 with silicon alkoxide (Japanese Patent Laid-Open No. 5-238827), glycidol addition obtained by reacting glycidol Polysilazane (JP-A-6-122852), alcohol-added polysilazane obtained by reacting an alcohol (JP-A-6-240208), metal carboxylate-added polysilazane obtained by reacting a metal carboxylate 6-299118), acetylacetonate complex-added polysilazane obtained by reacting a metal-containing acetylacetonate complex (JP-A-6-306329), metal fine particle-added polysilazane obtained by adding metal fine particles (specialty) Kaihei 7-19 986 JP), and the like.

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

  The polysilazane concentration in the polysilazane-containing coating solution is about 0.2% by mass to 35% by mass, although it varies depending on the target silica film thickness and the pot life of the coating solution.

  The organic polysilazane may be a derivative in which the hydrogen part bonded to Si is partially substituted with an alkyl group or the like. By having an alkyl group, especially a methyl group having the smallest molecular weight, the adhesion to the base material can be improved, and the hard and brittle silica film can be toughened, and even if the film thickness is increased, cracks are not generated. Occurrence is suppressed.

  In order to promote the modification to a silicon oxide compound, an amine or metal catalyst may be added. Specific examples include Aquamica NAX120-20, NN110, NN310, NN320, NL110A, NL120A, NL150A, NP110, NP140, and SP140 manufactured by AZ Electronic Materials Co., Ltd.

(Concentration of reaction catalyst contained in coating liquid containing polysilazane)
In the solution containing polysilazane according to the present invention (also referred to as coating solution), if necessary, hydrolysis and dehydration condensation is promoted by adding a reaction catalyst. Speed changes greatly.

  That is, if it is added too much, it will be a film having a large change with time due to excessive Si-OH groups.

  Further, as described above, when sufficient energy is applied to break molecular bonds such as irradiation with vacuum ultraviolet light, amine-based catalysts may be decomposed and evaporated.

  When decomposition and evaporation of the catalyst occur, impurities and voids are included in the reformed film, and the barrier property is deteriorated.

  In the present invention, in order to avoid excessive silanol formation by the catalyst, reduction in film density, and increase in film defects, it is preferable to adjust the amount of catalyst added to polysilazane to 2% by mass or less. Furthermore, it is more preferable not to add a catalyst from the viewpoint of suppressing Si—OH production.

<< Base material (also called support) >>
The substrate (support) according to the present invention will be described.

  The support of the barrier film of the present invention is particularly limited as long as it is formed of an organic material capable of holding a barrier layer (also referred to as a barrier film) having a gas barrier property (also referred to as a barrier property) described later. Is not to be done.

  For example, acrylic ester, methacrylic ester, polyethylene terephthalate (PET), polybutylene terephthalate, polyethylene naphthalate (PEN), polycarbonate (PC), polyarylate, polyvinyl chloride (PVC), polyethylene (PE), polypropylene (PP ), Polystyrene (PS), nylon (Ny), aromatic polyamide, polyether ether ketone, polysulfone, polyether sulfone, polyimide, polyetherimide, and other resin films, and silsesquioxane having an organic-inorganic hybrid structure Examples thereof include a heat-resistant transparent film having a skeleton (product name: Sila-DEC, manufactured by Chisso Corporation), and a resin film formed by laminating two or more layers of the resin.

  In terms of cost and availability, polyethylene terephthalate (PET), polybutylene terephthalate, polyethylene naphthalate (PEN), polycarbonate (PC), etc. are preferably used, and optical transparency, heat resistance, inorganic layer, gas barrier, etc. In terms of adhesion to the layer, a heat-resistant transparent film having a basic skeleton of silsesquioxane having an organic-inorganic hybrid structure can be preferably used. The thickness of the support is preferably about 5 μm to 500 μm, more preferably 25 μm to 250 μm.

  Moreover, it is preferable that the base material (support body) which concerns on this invention is transparent.

  Here, the base material being transparent means that the light transmittance of visible light (400 nm to 700 nm) is 80% or more.

  Since the base material (support) is transparent and the layer formed on the support is also transparent, a transparent barrier film can be obtained, so that it can also be a transparent substrate such as an organic EL element. Because it becomes.

  Further, the support using the above-described resins or the like may be an unstretched film or a stretched film.

  The support used in the present invention can be produced by a conventionally known general method. For example, an unstretched substrate (support) that is substantially amorphous and not oriented can be produced by melting a resin as a material with an extruder, extruding it with an annular die or a T-die, and quenching. it can.

  Further, an unstretched base material (support) can be formed by a known method such as uniaxial stretching, tenter sequential biaxial stretching, tenter simultaneous biaxial stretching, tubular simultaneous biaxial stretching, or the like. A stretched support can be produced by stretching in the flow (vertical axis) direction or in the direction perpendicular to the flow direction of the support (horizontal axis).

  The draw ratio in this case can be appropriately selected according to the resin as the raw material of the support, but is preferably 2 to 10 times in the vertical axis direction and the horizontal axis direction, respectively.

  Furthermore, in order to improve the dimensional stability of the substrate in the stretched film, it is preferable to perform a relaxation treatment after stretching.

  Further, the substrate (also referred to as a support) according to the present invention may be subjected to a corona treatment before forming a coating film. Furthermore, an anchor coating agent layer may be formed on the surface of the support according to the present invention for the purpose of improving the adhesion to the coating film.

《Anchor coating agent layer》
Examples of the anchor coating agent used in this anchor coating agent layer include polyester resin, isocyanate resin, urethane resin, acrylic resin, ethylene vinyl alcohol resin, vinyl modified resin, epoxy resin, modified styrene resin, modified silicon resin, and alkyl titanate. Can be used alone or in combination.

Conventionally known additives can be added to these anchor coating agents. The above-mentioned anchor coating agent is coated on the support by a known method such as roll coating, gravure coating, knife coating, dip coating, spray coating, etc., and anchor coating is performed by drying and removing the solvent, diluent, etc. be able to. The application amount of the anchor coating agent is preferably about 0.1 g / m ^{2 to} 5 g / m ² (dry state).

《Smooth layer》
The barrier film of the present invention may have a smooth layer.

  The smooth layer used in the present invention flattens the rough surface of the transparent resin film support with protrusions or the like, or fills the irregularities and pinholes generated in the transparent inorganic compound layer with the protrusions present on the transparent resin film support. Provided for flattening. Such a smooth layer is basically produced by curing a photosensitive resin.

  As the photosensitive resin of the smooth layer, for example, a resin composition containing an acrylate compound having a radical reactive unsaturated compound, a resin composition containing an acrylate compound and a mercapto compound having a thiol group, epoxy acrylate, urethane acrylate, Examples thereof include a resin composition in which a polyfunctional acrylate monomer such as polyester acrylate, polyether acrylate, polyethylene glycol acrylate, or glycerol methacrylate is dissolved. It is also possible to use an arbitrary mixture of the above resin compositions, and any photosensitive resin containing a reactive monomer having one or more photopolymerizable unsaturated bonds in the molecule can be used. There are no particular restrictions.

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

  In the formation of the smooth layer, additives such as an antioxidant, an ultraviolet absorber, and a plasticizer can be added to the above-described photosensitive resin as necessary. In addition, regardless of the position where the smooth layer is laminated, in any smooth layer, an appropriate resin or additive may be used in order to improve the film formability and prevent the generation of pinholes in the film.

  The smoothness of the smooth layer is a value expressed by the surface roughness specified by JIS B 0601, and the maximum cross-sectional height Rt (p) is preferably 10 nm or more and 30 nm or less. If the value is smaller than this range, the coating property is impaired when the coating means comes into contact with the surface of the smooth layer in the coating method such as a wire bar or wireless bar at the stage of coating the silicon compound described later. There is. Moreover, when larger than this range, it may become difficult to smooth the unevenness | corrugation after apply | coating a silicon compound.

<Bleed-out prevention layer>
The bleed-out prevention layer used in the present invention suppresses a phenomenon in which, when a film having a smooth layer is heated, unreacted oligomers migrate from the film support to the surface and contaminate the contact surface. For this purpose, it is provided on the opposite surface of the substrate having a smooth layer. The bleed-out prevention layer may basically have the same configuration as the smooth layer as long as it has this function.

  The unsaturated organic compound having a polymerizable unsaturated group that can be included in the bleed-out prevention layer is a polyunsaturated organic compound having two or more polymerizable unsaturated groups in the molecule or 1 in the molecule. Examples thereof include monounsaturated organic compounds having a single polymerizable unsaturated group.

  Here, examples of the polyunsaturated organic compound include ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, glycerol di (meth) acrylate, glycerol tri (meth) acrylate, 1,4-butanediol di ( (Meth) acrylate, 1,6-hexanediol di (meth) acrylate, neopentyl glycol di (meth) acrylate, trimethylolpropane tri (meth) acrylate, dicyclopentanyl di (meth) acrylate, pentaerythritol tri (meth) Acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol hexa (meth) acrylate, dipentaerythritol monohydroxypenta (meth) acrylate, ditrimethylolpropane Tiger (meth) acrylate, diethylene glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate, tripropylene glycol di (meth) acrylate, polypropylene glycol di (meth) acrylate.

  Moreover, as a unit price unsaturated organic compound, methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, isodecyl (meth) acrylate, Lauryl (meth) acrylate, stearyl (meth) acrylate, allyl (meth) acrylate, cyclohexyl (meth) acrylate, methylcyclohexyl (meth) acrylate, isobornyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (Meth) acrylate, glycerol (meth) acrylate, glycidyl (meth) acrylate, benzyl (meth) acrylate, 2-ethoxyethyl (meth) acrylate, 2- (2-e Xoxyethoxy) ethyl (meth) acrylate, butoxyethyl (meth) acrylate, 2-methoxyethyl (meth) acrylate, methoxydiethylene glycol (meth) acrylate, methoxytriethylene glycol (meth) acrylate, methoxypolyethylene glycol (meth) acrylate, 2- Examples include methoxypropyl (meth) acrylate, methoxydipropylene glycol (meth) acrylate, methoxytripropylene glycol (meth) acrylate, methoxypolypropylene glycol (meth) acrylate, polyethylene glycol (meth) acrylate, and polypropylene glycol (meth) acrylate. .

  As other additives, a matting agent may be contained. As the matting agent, inorganic particles having an average particle diameter of about 0.1 μm to 5 μm are preferable. As such inorganic particles, one or more of silica, alumina, talc, clay, calcium carbonate, magnesium carbonate, barium sulfate, aluminum hydroxide, titanium dioxide, zirconium oxide and the like can be used in combination. .

  Here, the matting agent composed of inorganic particles is 2 parts by mass or more, preferably 4 parts by mass or more, more preferably 6 parts by mass or more and 20 parts by mass or less, preferably 18 parts per 100 parts by mass of the solid content of the hard coat agent. It is desirable that they are mixed in a proportion of not more than part by mass, more preferably not more than 16 parts by mass.

  The bleed-out prevention layer may contain a thermoplastic resin, a thermosetting resin, an ionizing radiation curable resin, a photopolymerization initiator, and the like as other components of the hard coat agent and the mat agent.

  The bleed-out prevention layer as described above is mixed with a hard coat agent, a matting agent, and other components as necessary, and is prepared as a coating solution by using a diluent solvent as necessary, and supports the coating solution. It can form by apply | coating to a body film surface by a conventionally well-known coating method, and then irradiating with ionizing radiation and making it harden | cure.

  In addition, as a method of irradiating with ionizing radiation, ultraviolet rays having a wavelength region of 100 to 400 nm, preferably 200 nm to 400 nm emitted from an ultrahigh pressure mercury lamp, a high pressure mercury lamp, a low pressure mercury lamp, a carbon arc, a metal halide lamp, or the like are irradiated or scanned. The irradiation can be performed by irradiating an electron beam having a wavelength region of 100 nm or less emitted from a type or curtain type electron beam accelerator.

  The thickness of the bleed-out prevention layer is from the viewpoint of improving the heat resistance of the film, facilitating the balance adjustment of the optical properties of the film, and preventing curling when the bleed-out prevention layer is provided only on one side of the barrier film. The range of 1 μm to 10 μm is preferable, and the range of 2 μm to 7 μm is more preferable.

(Application of barrier film)
The barrier film of the present invention is mainly used in packages such as electronic devices, or display materials such as organic EL elements, solar cells, and plastic substrates such as liquid crystals, and resin substrates for various devices using the barrier film, and It can be applied to various device elements.

  The barrier film of the present invention can be preferably applied as various sealing materials and films.

(Organic photoelectric conversion element)
The organic photoelectric conversion element of the present invention will be described.

  The organic photoelectric conversion element of the present invention has the barrier film of the present invention as a component, but when used in the organic photoelectric conversion element, the barrier film is transparent, so this barrier film is used as a base material (also referred to as a support). And can be configured to receive sunlight from this side.

  That is, on this barrier film, for example, a transparent conductive thin film such as ITO can be provided as a transparent electrode to constitute a resin support for organic photoelectric conversion elements.

  Then, an ITO transparent conductive film provided on the support is used as an anode, a porous semiconductor layer is provided thereon, a cathode made of a metal film is further formed to form an organic photoelectric conversion element, and another seal is formed thereon. The organic photoelectric conversion element can be sealed by stacking a stop material (although it may be the same), adhering the barrier film support and the surroundings, and encapsulating the element. The influence on the element can be sealed.

  The resin support for organic photoelectric conversion elements is formed on the ceramic layer of the barrier film thus formed (herein, the ceramic layer includes a silicon oxide layer formed by modifying a polysilazane layer). Further, it is obtained by forming a transparent conductive film.

  The transparent conductive film can be formed by using a vacuum deposition method, a sputtering method, or the like, or by a coating method such as a sol-gel method using a metal alkoxide such as indium or tin.

  Moreover, as a film thickness of a transparent conductive film, the transparent conductive film of the range of 0.1 nm-1000 nm is preferable.

  Next, each layer (constituent layer) of the organic photoelectric conversion element material constituting the organic photoelectric conversion element will be described.

(Configuration of organic photoelectric conversion element and solar cell)
Although the preferable aspect of the organic photoelectric conversion element of this invention and the solar cell of this invention is demonstrated, this invention is not limited to these. In addition, although the preferable aspect of the organic photoelectric conversion element of this invention is demonstrated in detail hereafter, the solar cell of this invention has the organic photoelectric conversion element of this invention as the structure, and the preferable structure of a solar cell is also the same. Can be described.

  There is no restriction | limiting in particular as an organic photoelectric conversion element, A power generation layer (a layer in which a p-type semiconductor and an n-type semiconductor are mixed, a bulk heterojunction layer, or an i layer) sandwiched between the anode and the cathode is at least one layer. Any element that generates current when irradiated with light may be used.

  The preferable specific example of the layer structure of an organic photoelectric conversion element (The preferable layer structure of a solar cell is also the same) is shown below.

  The preferable specific example of the layer structure of an organic photoelectric conversion element is shown below.

(I) Anode / power generation layer / cathode (ii) Anode / hole transport layer / power generation layer / cathode (iii) Anode / hole transport layer / power generation layer / electron transport layer / cathode (iv) Anode / hole transport layer / P-type semiconductor layer / power generation layer / n-type semiconductor layer / electron transport layer / cathode (v) anode / hole transport layer / first power generation layer / electron transport layer / intermediate electrode / hole transport layer / second power generation layer / Electron transport layer / cathode.

  Here, the power generation layer needs to contain a p-type semiconductor material capable of transporting holes and an n-type semiconductor material capable of transporting electrons, and even if these layers form a heterojunction with substantially two layers. Alternatively, a bulk heterojunction in a mixed state in one layer may be manufactured, but a bulk heterojunction configuration is preferable because of higher photoelectric conversion efficiency. A p-type semiconductor material and an n-type semiconductor material used for the power generation layer will be described later.

  Like the organic EL element, the efficiency of taking out holes and electrons to the anode / cathode can be increased by sandwiching the power generation layer between the hole transport layer and the electron transport layer. Therefore, the structure having them ((ii), ( iii)) is preferred. Further, in order to improve the rectification of holes and electrons (selection of carrier extraction), the power generation layer itself is sandwiched between layers of a p-type semiconductor material and a single n-type semiconductor material as shown in (iv). A configuration (also referred to as a pin configuration) may be used. Moreover, in order to improve the utilization efficiency of sunlight, the tandem configuration (configuration (v)) in which sunlight of different wavelengths is absorbed by each power generation layer may be employed.

  Below, the material which comprises these layers is described.

(Organic photoelectric conversion element material)
The material used for formation of the electric power generation layer (it is also called a photoelectric converting layer) of the organic photoelectric conversion element of this invention is demonstrated.

(P-type semiconductor material)
Examples of the p-type semiconductor material preferably used as the power generation layer (bulk heterojunction layer) of the organic photoelectric conversion device of the present invention include various condensed polycyclic aromatic low molecular compounds and conjugated polymers / oligomers.

  Examples of the condensed polycyclic aromatic low-molecular compound include anthracene, tetracene, pentacene, hexacene, heptacene, chrysene, picene, fluorene, pyrene, peropyrene, perylene, terylene, quaterylene, coronene, ovalene, circumanthracene, bisanthene, zesulene, Compounds such as heptazeslen, pyranthrene, violanthene, isoviolanthene, circobiphenyl, anthradithiophene, porphyrin, copper phthalocyanine, tetrathiafulvalene (TTF) -tetracyanoquinodimethane (TCNQ) complex, bisethylenetetrathiafulvalene (BEDTTTTF ) -Perchloric acid complexes, and derivatives and precursors thereof.

  Examples of the derivative having the above condensed polycycle include International Publication No. 03/16599, International Publication No. 03/28125, US Pat. No. 6,690,029, Japanese Patent Application Laid-Open No. 2004-107216. A pentacene derivative having a substituent described in JP-A No. 2003-136964, a pentacene precursor described in US Patent Application Publication No. 2003/136964, and the like; Amer. Chem. Soc. , Vol127. No. 14.4986, J. MoI. Amer. Chem. Soc. , Vol. 123, p9482; Amer. Chem. Soc. , Vol. 130 (2008), no. 9, acene-based compounds substituted with a trialkylsilylethynyl group described in 2706 and the like.

  As the conjugated polymer, for example, a polythiophene such as poly-3-hexylthiophene (P3HT) and an oligomer thereof, or a technical group described in Technical Digest of the International PVSEC-17, Fukuoka, Japan, 2007, P1225. Polythiophene, Nature Material, (2006) vol. 5, p328, a polythiophene-thienothiophene copolymer, a polythiophene-diketopyrrolopyrrole copolymer described in WO08 / 000664, and a polythiophene-thiazolothiazole copolymer described in Adv Mater, 2007p4160 , Nature Mat. vol. 6 (2007), p497 described in PCPDTBT, etc., polypyrrole and its oligomer, polyaniline, polyphenylene and its oligomer, polyphenylene vinylene and its oligomer, polythienylene vinylene and its oligomer, polyacetylene, polydiacetylene, Examples thereof include polymer materials such as σ-conjugated polymers such as polysilane and polygermane.

  In addition, oligomeric materials instead of polymer materials include thiophene hexamer α-sexual thiophene α, ω-dihexyl-α-sexual thiophene, α, ω-dihexyl-α-kinkethiophene, α, ω-bis (3 Oligomers such as -butoxypropyl) -α-sexithiophene can be preferably used.

  Among these compounds, a compound that is highly soluble in an organic solvent to the extent that a solution process is possible and that can produce a crystalline thin film and achieve high mobility after drying is preferable.

  In addition, when the electron transport layer is formed on the power generation layer by coating, there is a problem that the electron transport layer solution dissolves the power generation layer. Therefore, a material that can be insolubilized after coating by a solution process may be used. .

  Examples of such a material include materials that can be insolubilized by polymerizing and crosslinking the coating film after coating, such as polythiophene having a polymerizable group described in Technical Digest of the International PVSEC-17, Fukuoka, Japan, 2007, P1225. Or by applying energy such as heat as described in US Patent Application Publication No. 2003/136964 and JP-A-2008-16834, etc., the soluble substituent reacts to insolubilize ( And materials).

(N-type semiconductor material)
The n-type semiconductor material used for the bulk heterojunction layer according to the present invention is not particularly limited. For example, a perfluoro compound (perfluoropentacene or the like) in which a hydrogen atom of a p-type semiconductor such as fullerene or octaazaporphyrin is substituted with a fluorine atom. Perfluorophthalocyanine, etc.), naphthalenetetracarboxylic anhydride, naphthalenetetracarboxylic acid diimide, perylenetetracarboxylic acid anhydride, perylenetetracarboxylic acid diimide and other aromatic carboxylic acid anhydrides, and polymers containing such imidized compounds as a skeleton A compound etc. can be mentioned.

  However, fullerene derivatives that can perform charge separation efficiently with various p-type semiconductor materials at high speed (˜50 fs) are preferable. Fullerene derivatives include fullerene C60, fullerene C70, fullerene C76, fullerene C78, fullerene C84, fullerene C240, fullerene C540, mixed fullerene, fullerene nanotubes, multi-walled nanotubes, single-walled nanotubes, nanohorns (conical), etc. Partially by hydrogen atom, halogen atom, substituted or unsubstituted alkyl group, alkenyl group, alkynyl group, aryl group, heteroaryl group, cycloalkyl group, silyl group, ether group, thioether group, amino group, silyl group, etc. Examples thereof include substituted fullerene derivatives.

  Among them, [6,6] -phenyl C61-butyric acid methyl ester (abbreviation PCBM), [6,6] -phenyl C61-butyric acid-nbutyl ester (PCBnB), [6,6] -phenyl C61- Butyric acid-isobutyl ester (PCBiB), [6,6] -phenyl C61-butyric acid-n-hexyl ester (PCBH), Adv. Mater. , Vol. 20 (2008), p2116, etc., aminated fullerenes such as JP-A 2006-199674, metallocene fullerenes such as JP-A 2008-130889, US Pat. No. 7,329,709, etc. It is preferable to use a fullerene derivative having a substituent and having improved solubility, such as fullerene having a cyclic ether group such as a calligraphy.

(Hole transport layer / electron block layer)
In the organic photoelectric conversion element 10 of the present invention, the hole transport layer 17 can be taken out between the bulk heterojunction layer and the anode, and charges generated in the bulk heterojunction layer can be taken out more efficiently. It is preferable to have.

  As a material constituting these layers, for example, as the hole transport layer 17, PEDOT such as Product name BaytronP manufactured by Stark Vitec, polyaniline and its doped material, described in WO 06/19270, etc. Cyanide compounds can be used.

  Note that the hole transport layer having a LUMO level shallower than the LUMO level of the n-type semiconductor material used for the bulk heterojunction layer has a rectifying effect that prevents electrons generated in the bulk heterojunction layer from flowing to the anode side. The electronic block function is provided.

  Such a hole transport layer is also called an electron block layer, and it is preferable to use a hole transport layer having such a function. As such a material, a triarylamine compound described in JP-A-5-271166 or a metal oxide such as molybdenum oxide, nickel oxide, or tungsten oxide can be used.

  A layer made of a single p-type semiconductor material used for the bulk heterojunction layer can also be used. As a means for producing these layers, either a vacuum vapor deposition method or a solution coating method may be used, but a solution coating method is preferable. It is preferable to produce a coating film in the lower layer before producing the bulk heterojunction layer because it has the effect of leveling the application surface and reduces the influence of leakage and the like.

(Electron transport layer / hole blocking layer)
In the organic photoelectric conversion element 10 of the present invention, it is possible to more efficiently extract charges generated in the bulk heterojunction layer by producing the electron transport layer 18 between the bulk heterojunction layer and the cathode. It is preferable to have these layers.

  As the electron transport layer 18, octaazaporphyrin, a p-type semiconductor perfluoro product (perfluoropentacene, perfluorophthalocyanine, or the like) can be used. Similarly, a p-type semiconductor material used for a bulk heterojunction layer is used. The electron transport layer having a HOMO level deeper than the HOMO level is given a hole blocking function having a rectifying effect so that holes generated in the bulk heterojunction layer do not flow to the cathode side.

  Such an electron transport layer is also called a hole blocking layer, and it is preferable to use an electron transport layer having such a function.

  Examples of such materials include phenanthrene compounds such as bathocuproine, n-type semiconductor materials such as naphthalenetetracarboxylic acid anhydride, naphthalenetetracarboxylic acid diimide, perylenetetracarboxylic acid anhydride, perylenetetracarboxylic acid diimide, and titanium oxide. N-type inorganic oxides such as zinc oxide and gallium oxide, and alkali metal compounds such as lithium fluoride, sodium fluoride, and cesium fluoride can be used.

  A layer made of a single n-type semiconductor material used for the bulk heterojunction layer can also be used. As a means for producing these layers, either a vacuum vapor deposition method or a solution coating method may be used, but a solution coating method is preferable.

(Other layers)
For the purpose of improving energy conversion efficiency and improving the lifetime of the element, a structure having various intermediate layers in the element may be employed. Examples of the intermediate layer include a hole block layer, an electron block layer, a hole injection layer, an electron injection layer, an exciton block layer, a UV absorption layer, a light reflection layer, and a wavelength conversion layer.

(Transparent electrode (first electrode))
In the transparent electrode according to the present invention, the cathode and the anode are not particularly limited and can be selected depending on the element configuration, but preferably the transparent electrode is used as the anode. For example, when used as an anode, it is preferably an electrode that transmits light of 380 nm to 800 nm.

As the material, for example, transparent conductive metal oxides such as indium tin oxide (ITO), SnO ₂ and ZnO, metal thin films such as gold, silver and platinum, metal nanowires and carbon nanotubes can be used.

  Also selected from the group consisting of derivatives of polypyrrole, polyaniline, polythiophene, polythienylene vinylene, polyazulene, polyisothianaphthene, polycarbazole, polyacetylene, polyphenylene, polyphenylene vinylene, polyacene, polyphenylacetylene, polydiacetylene and polynaphthalene. Conductive polymers can also be used. A plurality of these conductive compounds can be combined to form a transparent electrode.

(Counter electrode (second electrode))
The counter electrode may be a single layer of a conductive material, but in addition to a conductive material, a resin that holds these may be used in combination. As the conductive material of the counter electrode, a material having a small work function (4 eV or less) metal, alloy, electrically conductive compound and a mixture thereof 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 viewpoint of electron extraction performance and durability against oxidation, etc., a mixture of these metals and a second metal which is a stable metal having a larger work function value 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 counter electrode can be produced by producing a thin film of these electrode materials by a method such as vapor deposition or sputtering. The film thickness is usually selected in the range of 10 nm to 5 μm, preferably 50 nm to 200 nm.

  If a metal material is used as the conductive material of the counter electrode, the light coming to the counter electrode side is reflected and reflected to the first electrode side, and this light can be reused and absorbed again by the photoelectric conversion layer, and more photoelectric conversion is performed. Efficiency is improved and preferable.

  The counter electrode 13 may be a metal (for example, gold, silver, copper, platinum, rhodium, ruthenium, aluminum, magnesium, indium, etc.), a nanoparticle made of carbon, a nanowire, or a nanostructure. A wire dispersion is preferable because a transparent and highly conductive counter electrode can be produced by a coating method.

  Moreover, when making the counter electrode side light-transmitting, for example, after forming a conductive material suitable for the counter electrode such as aluminum and aluminum alloy, silver and silver compound in a thin film thickness of about 1 to 20 nm, By providing a film of the conductive light transmissive material mentioned in the description of the transparent electrode, a light transmissive counter electrode can be obtained.

(Intermediate electrode)
In addition, the material of the intermediate electrode required in the case of the tandem configuration as in (v) (or FIG. 3) is preferably a layer using a compound having both transparency and conductivity. (Such as ITO, AZO, FTO, transparent metal oxides such as titanium oxide, very thin metal layers such as Ag, Al, Au, etc., or layers containing nanoparticles / nanowires, PEDOT: PSS, polyaniline) Or the like can be used.

  In addition, in the hole transport layer and the electron transport layer described above, there is also a combination that works as an intermediate electrode (charge recombination layer) by appropriately stacking them. Is preferable.

(Metal nanowires)
As the conductive fiber according to the present invention, an organic fiber or inorganic fiber coated with a metal, a conductive metal oxide fiber, a metal nanowire, a carbon fiber, a carbon nanotube, or the like can be used, and a metal nanowire is preferable.

  In general, the metal nanowire refers to a linear structure having a metal element as a main component. In particular, the metal nanowire in the present invention means a linear structure having a diameter of nm size.

  The metal nanowire according to the present invention preferably has an average length of 3 μm or more in order to produce a long conductive path with one metal nanowire, and to express appropriate light scattering properties. Furthermore, 3 micrometers-500 micrometers are preferable, and it is especially preferable that they are 3 micrometers-300 micrometers. In addition, the relative standard deviation of the length is preferably 40% or less.

  Moreover, it is preferable that an average diameter is small from a transparency viewpoint, On the other hand, the larger one is preferable from an electroconductive viewpoint. In the present invention, the average diameter of the metal nanowire is preferably 10 nm to 300 nm, and more preferably 30 nm to 200 nm. In addition, the relative standard deviation of the diameter is preferably 20% or less.

  There is no restriction | limiting in particular as a metal composition of the metal nanowire which concerns on this invention, Although it can comprise from the 1 type or several metal of a noble metal element or a base metal element, noble metals (for example, gold, platinum, silver, palladium, rhodium) Iridium, ruthenium, osmium, and the like) and at least one metal belonging to the group consisting of iron, cobalt, copper, and tin, and more preferably at least silver from the viewpoint of conductivity.

  In order to achieve both conductivity and stability (sulfurization and oxidation resistance of metal nanowires and migration resistance), it is also preferable to include silver and at least one metal belonging to a noble metal other than silver. When the metal nanowire according to the present invention includes two or more kinds of metal elements, for example, the metal composition may be different between the inside and the surface of the metal nanowire, or the entire metal nanowire has the same metal composition. You may have.

  In the present invention, there are no particular limitations on the means for producing the metal nanowire, and for example, known means such as a liquid phase method and a gas phase method can be used. Moreover, there is no restriction | limiting in particular in a specific manufacturing method, A well-known manufacturing method can be used.

  For example, as a manufacturing method of Ag nanowire, Adv. Mater. , 2002, 14, 833-837; Chem. Mater. , 2002, 14, 4736-4745, etc., as a method for producing Au nanowires, such as JP 2006-233252A, etc., as a method for producing Cu nanowires, JP 2002-266007 A, etc. For example, Japanese Patent Application Laid-Open No. 2004-149871 can be referred to. In particular, Adv. Mater. And Chem. Mater. The method for producing Ag nanowires reported in 1 can easily produce Ag nanowires in an aqueous system, and since the conductivity of silver is the highest among metals, the production of metal nanowires according to the present invention is possible. It can be preferably applied as a method.

  In the present invention, metal nanowires are brought into contact with each other to produce a three-dimensional conductive network, exhibiting high conductivity, and allowing light to pass through a window portion of the conductive network where there is no metal nanowire. In addition, the power generation from the organic power generation layer can be efficiently performed by the scattering effect of the metal nanowires. If a metal nanowire is installed in the 1st electrode at the side close | similar to an organic electric power generation layer part, since this scattering effect can be utilized more effectively, it is more preferable embodiment.

(Optical function layer)
The organic photoelectric conversion element of the present invention may have various optical functional layers for the purpose of more efficient light reception of sunlight. As the optical functional layer, for example, a light condensing layer such as an antireflection layer or a microlens array, or a light diffusion layer that can scatter light reflected by the cathode and enter the power generation layer again may be provided. .

  Various known antireflection layers can be provided as the antireflection layer. For example, when the transparent resin film is a biaxially stretched polyethylene terephthalate film, the refractive index of the easy adhesion layer adjacent to the film is 1.57. It is more preferable to set it to ˜1.63 because the interface reflection between the film substrate and the easy adhesion layer can be reduced and the transmittance can be improved. The method for adjusting the refractive index can be carried out by appropriately adjusting the ratio of the oxide sol having a relatively high refractive index such as tin oxide sol or cerium oxide sol and the binder resin. The easy adhesion layer may be a single layer, but may be composed of two or more layers in order to improve adhesion.

  As the condensing layer, for example, it is processed so as to provide a structure on the microlens array on the sunlight receiving side of the support substrate, or the amount of light received from a specific direction is increased by combining with a so-called condensing sheet. Conversely, the incident angle dependency of sunlight can be reduced.

  As an example of the microlens array, quadrangular pyramids having a side of 30 μm and an apex angle of 90 degrees are two-dimensionally arranged on the light extraction side of the substrate. One side is preferably 10 μm to 100 μm. If it becomes smaller than this, the effect of diffraction will generate | occur | produce and color, and if too large, thickness will become thick and is not preferable.

  Examples of the light diffusion layer include various antiglare layers, layers in which nanoparticles or nanowires such as metals or various inorganic oxides are dispersed in a colorless and transparent polymer, and the like.

(Film formation method / surface treatment method)
Examples of a method for producing a bulk heterojunction layer in which an electron acceptor and an electron donor are mixed, and a transport layer / electrode include a vapor deposition method and a coating method (including a cast method and a spin coat method). Among these, examples of the method for producing the bulk heterojunction layer include a vapor deposition method and a coating method (including a casting method and a spin coating method).

  Among these, the coating method is preferable in order to increase the area of the interface where charges and electrons are separated from each other as described above and to produce a device having high photoelectric conversion efficiency. Also, the coating method is excellent in production speed.

  Although there is no restriction | limiting in the coating method used in this case, For example, a spin coat method, the cast method from a solution, a dip coat method, a blade coat method, a wire bar coat method, a gravure coat method, a spray coat method etc. are mentioned. Furthermore, patterning can also be performed by a printing method such as an inkjet method, a screen printing method, a relief printing method, an intaglio printing method, an offset printing method, a flexographic printing method, or the like.

  After application, it is preferable to perform heating in order to cause removal of residual solvent, moisture, and gas and increase mobility and absorption longwave by crystallization of the semiconductor material. When annealing is performed at a predetermined temperature during the manufacturing process, a part of the particles is microscopically aggregated or crystallized, and the bulk heterojunction layer can have an appropriate phase separation structure. As a result, the carrier mobility of the bulk heterojunction layer is improved and high efficiency can be obtained.

  The power generation layer (bulk heterojunction layer) 14 may be composed of a single layer in which an electron acceptor and an electron donor are uniformly mixed, but a plurality of layers in which the mixing ratio of the electron acceptor and the electron donor is changed. You may comprise. In this case, it can be manufactured by using a material that can be insolubilized after coating as described above.

(Patterning)
The method and process for patterning the electrode, the power generation layer, the hole transport layer, the electron transport layer, and the like according to the present invention are not particularly limited, and known methods can be appropriately applied.

  If it is a soluble material such as a bulk heterojunction layer or a transport layer, only unnecessary portions may be wiped after the entire surface of die coating, dip coating, etc., or direct patterning at the time of coating using a method such as an ink jet method or screen printing. May be.

  In the case of an insoluble material such as an electrode material, the electrode can be patterned by a known method such as mask vapor deposition during vacuum deposition or etching or lift-off. Alternatively, the pattern may be produced by transferring a pattern produced on another substrate.

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

Example 1
<< Preparation of Barrier Film 1 >>
As described below, first, a base material was produced, and then a barrier film 1 was produced through a process of producing a barrier layer on the base material.

<Production of base material>
A 125 μm thick polyester film (Teijin DuPont Films Co., Ltd., extremely low heat yield PET Q83) which is a thermoplastic resin support and is easily bonded on both sides is used. As shown below, a bleed-out prevention layer is provided on one side. A substrate having a smooth layer formed on the opposite surface was used as a substrate.

(Formation of bleed-out prevention layer)
A UV curing type organic / inorganic hybrid hard coating material OPSTAR Z7535 manufactured by JSR Co., Ltd. is applied to one side of the above support, applied with a wire bar so that the film thickness after drying is 4 μm, and then curing conditions: 1.0 J / cm ² under air, a high pressure mercury lamp used, drying conditions; 80 ° C., subjected to cure for 3 minutes to form a bleedout-preventing layer.

(Formation of smooth layer)
Subsequently, a UV curable organic / inorganic hybrid hard coat material OPSTAR Z7501 manufactured by JSR Corporation is applied to the opposite surface of the support, and is applied with a wire bar so that the film thickness after drying is 4 μm, and then drying conditions; After drying at 80 ° C. for 3 minutes, a high pressure mercury lamp was used in an air atmosphere, curing conditions; 1.0 J / cm ² curing was performed to form a smooth layer.

  The obtained smooth layer had a surface roughness specified by JIS B 0601 and a maximum cross-sectional height Rt (p) of 16 nm.

  The surface roughness is calculated from an uneven cross-sectional curve continuously measured with an AFM (Atomic Force Microscope) and a detector having a stylus with a minimum tip radius, and the measurement direction is 30 μm with a stylus with a minimum tip radius. This is the average roughness for the amplitude of fine irregularities, measured many times in the section.

<< Preparation of barrier layer >>
On the smooth layer of the base material obtained above, a barrier layer was prepared by the following steps (a) and (b).

Step (a): Production of perhydropolysilazane layer The base material provided with the smooth layer and the bleed-out prevention layer is cut into a 10 cm square, and a coating solution containing perhydropolysilazane shown below is formed on the smooth layer surface. This was applied to prepare a perhydropolysilazane layer (also referred to as a layer containing perhydropolysilazane).

(Coating liquid containing perhydropolysilazane)
As the coating liquid containing perhydropolysilazane, a 20% by mass dibutyl ether solution (Aquamica NN120-20 manufactured by AZ Electronic Materials Co., Ltd.) was used, and this solution was diluted with dibutyl ether to adjust the PHPS concentration and spin. After coating by the coating method, it was dried at 80 ° C. for 3 minutes, and after drying, a perhydropolysilazane layer having a thickness of 170 nm was produced. At this time, the polysilazane-containing layer was not completely solidified.

Step (b): Preparation of a barrier layer by modification (oxidation) of the perhydropolysilazane layer. The perhydropolysilazane layer obtained in the above step (a) is irradiated with the vacuum ultraviolet ray (VUV) described below, A barrier layer was produced, and a barrier film 1 (comparative) was produced.

(Vacuum ultraviolet (VUV) irradiation treatment conditions)
Using a stage movable xenon excimer irradiation device MODEL: MECL-M-1-200 (wavelength 172 nm) manufactured by MD Excimer, the sample was fixed so that the irradiation distance between the lamp and the sample was 1 mm, and the sample temperature was 75. The sample was reciprocated at a moving speed of the stage of 10 mm / second while keeping the temperature at 0 ° C., and the sample was taken out after a total of 5 reciprocation irradiations.

(Adjustment of oxygen concentration)
The oxygen concentration at the time of vacuum ultraviolet (VUV) irradiation is determined by measuring the flow rate of nitrogen gas and oxygen gas introduced into the vacuum ultraviolet (VUV) irradiation chamber with a flow meter, and nitrogen gas / oxygen of the gas introduced into the irradiation chamber. It adjusted so that oxygen concentration might be in the range of 0.9 volume%-1.1 volume% by gas flow rate ratio.

<< Preparation of barrier film 2 >>
In the production of the barrier film 1, a barrier film 2 was produced in the same manner except that the following surface treatment was performed between the step of forming the perhydropolysilazane layer and the step of irradiating with vacuum ultraviolet rays (VUV).

(surface treatment)
Using a UV ozone cleaner Model UV-1 manufactured by SAMCO, the atmosphere at the time of irradiation was replaced with nitrogen, and the ozone concentration was adjusted to 300 ppm, and the treatment was performed for 5 minutes.

<< Preparation of Barrier Film 3 >>
In the production of the barrier film 1, a barrier film 3 was produced in the same manner except that the following surface treatment was performed between the step of forming the perhydropolysilazane layer and the step of irradiating with vacuum ultraviolet rays (VUV).

(surface treatment)
Using a plasma cleaner Model PC-300 manufactured by SAMCO, treatment was performed for 3 minutes in RIE mode with an oxygen supply rate of 0.5 L / min.

<< Preparation of barrier film 4 >>
In the production of the barrier film 1, a barrier film 4 was produced in the same manner except that the following surface treatment was performed between the step of forming the perhydropolysilazane layer and the step of irradiating with vacuum ultraviolet rays (VUV).

(surface treatment)
The surface of the sample was applied with a voltage of 6 kV, treated at 30 W · min per m ² , and subjected to corona discharge for 3 minutes.

<< Preparation of barrier film 5 >>
In the production of the barrier film 1, a barrier film 5 was produced in the same manner except that the following surface treatment was performed between the step of forming the perhydropolysilazane layer and the step of irradiating with vacuum ultraviolet rays (VUV).

(surface treatment)
A stage heater type xenon excimer irradiator MODEL manufactured by MD Excimer Co., Ltd. A halogen heater unit IRE500W-N manufactured by Iwasaki Electric Co., Ltd. is attached so as to be parallel to the excimer light source of MECL-M-1-200. After fixing the sample so that the irradiation distance is 60 mm and adjusting the oxygen concentration to be in the range of 0.9 vol% to 1.1 vol%, the stage moving speed is 30 mm / sec. Were reciprocated and irradiated for a total of 5 reciprocations.

<< Preparation of barrier film 6 >>
In the production of the barrier film 5, a barrier film 6 was produced in the same manner except that the following surface treatment was performed between the step of forming the perhydropolysilazane layer and the step of irradiating with vacuum ultraviolet rays (VUV).

(surface treatment)
A halogen heater unit IRE500W-N manufactured by Iwasaki Electric Co., Ltd. is attached so that irradiation is performed from the side opposite to the surface on which the perhydropolysilazane layer is formed in the surface treatment during the production of the barrier film 5, and the irradiation distance between the lamp and the sample is 60 mm. The sample is fixed so that the oxygen concentration is in the range of 0.9 vol% to 1.1 vol%, and then the stage is moved back and forth at a speed of 40 mm / sec. A total of 5 reciprocations were irradiated.

<< Preparation of barrier film 7 >>
In the production of the barrier film 6, after the step of forming the perhydropolysilazane layer, the step of irradiating with vacuum ultraviolet rays (VUV) and the surface treatment (irradiating with infrared rays from the opposite side of the formation surface of the perhydropolysilazane layer) were performed at the same time. A barrier film 7 was produced in the same manner.

<< Preparation of barrier film 8 >>
In the production of the barrier film 1, the sample after the formation of the perhydropolysilazane layer is 95% by volume of nitrogen in the xenon excimer irradiation apparatus MODEL: MECL-M-1-200, that is, the oxygen concentration is approximately 5% by volume. The sample was stored in a sealed space with the sample temperature adjusted to 90 ° C. for 1 hour, and after adjusting the oxygen concentration to be in the range of 0.9% to 1.1% by volume, the vacuum in the next step A barrier film 8 was produced in the same manner except that the modification treatment by ultraviolet (VUV) irradiation was performed.

<< Preparation of barrier film 9 >>
In the production of the barrier film 1, dry nitrogen gas is sprayed at a distance of 2 mm from a slit having a width of 100 mm and a gap of 0.3 mm onto the sample surface after the formation of the perhydropolysilazane layer in a xenon excimer irradiation apparatus. Then, the barrier film 9 was prepared in the same manner except that the subsequent vacuum ultraviolet irradiation (VUV) was performed.

<< Production of Barrier Film 10 >>
In the production of the barrier film 9, the surface treatment means is placed adjacent to a position 10 mm lateral to the vacuum ultraviolet (VUV) irradiation light source, and vacuum ultraviolet (VUV) irradiation is performed while performing surface treatment (blowing dry nitrogen gas from a distance of 2 mm). A barrier film 10 was produced in the same manner except that.

<< Preparation of Barrier Film 11 >>
In the production of the barrier film 8, the sample after the formation of the perhydropolysilazane layer was adjusted so that the nitrogen concentration was 99% by volume, that is, the oxygen concentration was approximately 1%, and the sample temperature was adjusted to 100 ° C. A barrier film 11 was produced in the same manner except that the sample that had been stored for a period of time was irradiated with vacuum ultraviolet rays (VUV) in the next step while maintaining the atmosphere.

<< Preparation of Barrier Film 12 >>
In the production of the barrier film 8, the sample after the formation of the perhydropolysilazane layer is adjusted so that the nitrogen concentration is 90% by volume, that is, the oxygen concentration is approximately 10%, and the next step of irradiation with vacuum ultraviolet (VUV) light is performed. A barrier film 12 was produced in the same manner as described above.

<< Preparation of barrier film 13 >>
In the production of the barrier film 7, the barrier film 13 was produced in the same manner except that the vacuum ultraviolet (VUV) light source was changed from a xenon excimer lamp to a fluorine excimer having a central wavelength of 158 nm.

<< Measurement and evaluation of water vapor permeability immediately after barrier film preparation >>
About each of the barrier films 1-13, the water-vapor-permeation rate was measured as shown below, 5-stage rank evaluation was performed as shown below, and gas barrier property was evaluated.

(Measurement device of water vapor transmission rate)
Vapor deposition apparatus: Vacuum vapor deposition apparatus JEE-400 manufactured by JEOL Ltd.
Constant temperature and humidity oven: Yamato Humidic Chamber IG47M
(raw materials)
Metal that reacts with water and corrodes: Calcium (granular)
Water vapor-impermeable metal: Aluminum (φ3-5mm, granular)
(Preparation of water vapor barrier property evaluation cell)
Using a vacuum vapor deposition device (JEOL-made vacuum vapor deposition device JEE-400), masking the portions other than the portions (12 mm × 12 mm 9 locations) to be deposited on the barrier films 1 to 13 before attaching the transparent conductive film, and metal calcium Was evaporated.

  Thereafter, the mask was removed in a vacuum state, and aluminum was deposited from another metal deposition source on the entire surface of one side of the sheet. After aluminum sealing, the vacuum state is released, and immediately facing the aluminum sealing side through a UV-curable resin for sealing (made by Nagase ChemteX) on quartz glass with a thickness of 0.2 mm in a dry nitrogen gas atmosphere The cell for evaluation was produced by irradiating with ultraviolet rays.

  The obtained sample with both sides sealed is stored at 60 ° C. and 90% RH under high temperature and high humidity, and moisture permeated into the cell from the corrosion amount of metallic calcium based on the method described in JP-A-2005-283561. The amount was calculated.

(Rank evaluation)
Less than 5: 1 × 10 ⁻⁴ g / m ² / day 4: 1 × 10 ⁻⁴ g / m ² / day or more, less than 1 × 10 ⁻³ g / m ² / day 3: 1 × 10 ⁻³ g / day m ² / day or more, 1 × 10 ⁻² g / m ² / day or less 2: 1 × 10 ⁻² g / m ² / day or more, 1 × 10 ⁻¹ g / m ² / day or less 1: 1 × 10 ⁻¹ g / m ² / day or more In rank evaluation, rank 3 or more can withstand practical use.

<< Water vapor permeability after aging of barrier film (85 ° C, 7 days) >>
The obtained barrier film was stored in the following constant temperature and humidity chamber adjusted to 85 ° C. for 7 consecutive days, and then the water vapor transmission rate was measured by the same method and evaluation rank as described above to determine the stability of the barrier film over time. evaluated.

Constant temperature and humidity oven: Yamato Humidic Chamber IG47M
<< Measurement and evaluation of surface roughness of barrier layer >>
The surface roughness is calculated from an uneven cross-sectional curve continuously measured with an AFM (Atomic Force Microscope) and a detector having a stylus with a minimum tip radius, and the measurement direction is 30 μm with a stylus with a minimum tip radius. This is the average roughness for the amplitude of fine irregularities, measured many times in the section.

In the table, the Rt of the barrier layer changes due to fine unevenness as a result of receiving the surface treatment energy.
Evaluation rank of surface smoothness Rt (5 levels)
5: Less than 5 nm 4: 5 nm or more, less than 10 nm 3: 10 nm or more, less than 20 nm 2: 20 nm or more, less than 30 nm 1: 30 nm or more << Bend resistance test >>
The water vapor transmission rate was evaluated in the same manner as described above except that the barrier films 1 to 13 were bent 100 times at an angle of 180 degrees so that the curvature of the barrier films 1 to 13 had a radius of 10 mm.

  The results obtained are shown in Table 1.

  From Table 1, compared with the comparative barrier film 1, the barrier films 2 to 13 of the present invention have good gas barrier properties (low water vapor transmission rate) immediately after production, and even after aging at 85 ° C. for 7 days. It can be seen that extremely good gas barrier properties are exhibited. It is also clear that the gas barrier property after the bending test is very good.

  In addition, also about the presence or absence of surface treatment, it turns out that the surface of the barrier layer of the barrier film of this invention has the surface smoothness equivalent to the comparative barrier film 1 without a surface treatment after the surface treatment.

Example 2
<< Production of Organic Photoelectric Conversion Elements 1-13 >>
Indium tin oxide (ITO) transparent conductive film deposited in a thickness of 150 nm on each of barrier films 1 to 13 obtained immediately after production (meaning pre-aging storage treatment) obtained in Example 1 (sheet resistance 10Ω / □) was patterned to a width of 2 mm using a normal photolithography technique and wet etching to form a first electrode.

  The patterned first electrode was washed in the order of ultrasonic cleaning with a surfactant and ultrapure water, followed by ultrasonic cleaning with ultrapure water, dried with nitrogen blow, and finally subjected to ultraviolet ozone cleaning.

  On this transparent substrate, Baytron P4083 (manufactured by Starck Vitec), which is a conductive polymer, was applied and dried to a film thickness of 30 nm, and then heat treated at 150 ° C. for 30 minutes to form a hole transport layer. .

  Thereafter, the substrate was brought into a nitrogen chamber and manufactured in a nitrogen atmosphere.

  First, the substrate was heat-treated at 150 ° C. for 10 minutes in a nitrogen atmosphere. Next, P3HT (manufactured by Prectronics: regioregular poly-3-hexylthiophene) and PCBM (manufactured by Frontier Carbon Co., Ltd .: 6,6-phenyl-C61-butyric acid methyl ester) are added to 3.0% by mass of chlorobenzene. A liquid mixed at 1: 0.8 was prepared so that the film thickness was 100 nm while being filtered through a filter, and the film was allowed to stand at room temperature and dried. Subsequently, a heat treatment was performed at 150 ° C. for 15 minutes to form a photoelectric conversion layer.

Next, the substrate on which the series of functional layers is formed is moved into a vacuum deposition apparatus chamber, the inside of the vacuum deposition apparatus is depressurized to 1 × 10 ⁻⁴ Pa or less, and then fluorinated at a deposition rate of 0.01 nm / second. Laminate 0.6 nm of lithium, and then continue to deposit 100 nm of Al metal at a deposition rate of 0.2 nm / sec through a shadow mask with a width of 2 mm (vaporization is performed so that the light receiving part is 2 × 2 mm). A second electrode was formed. The obtained organic photoelectric conversion element was moved to a nitrogen chamber, and a sealing process was performed as described below using a sealing cap and a UV curable resin. 13 were prepared.

(Sealing of organic photoelectric conversion elements)
Under an environment purged with nitrogen gas (inert gas), two each of the barrier films 1 to 13 were used, and an epoxy photocurable adhesive was applied as a sealing material to the surface provided with the barrier layer.

  The organic photoelectric conversion elements 1 to 13 before sealing obtained by the method described above are sandwiched between the adhesive application surfaces of the two barrier films 1 to 13 for sealing and coated with the adhesive. After that, UV light was applied from one side of the substrate to cure the organic photoelectric conversion elements 1 to 13 after the sealing treatment.

<< Production of solar cells and evaluation of energy conversion efficiency >>
Evaluation of the organic photoelectric conversion elements 1-13 obtained above produced each solar cell 1-13 using each element, calculated | required energy conversion efficiency, and evaluated the durability as an element.

In addition, preparation of the solar cells 1-13 irradiates each of the organic photoelectric conversion elements 1-13 with the light of the intensity | strength of 100 mW / cm < ² > of a solar simulator (AM1.5G filter), and an effective area is set to 4.0 mm < ² >. By overlapping the mask formed on the light receiving portion and evaluating the IV characteristics, a short-circuit current density Jsc (mA / cm ² ), an open circuit voltage Voc (V), and a fill factor FF (%) were formed on the same element 4 Each of the light receiving portions was measured, and an average value of four points of the energy conversion efficiency PCE (%) obtained according to the following formula 1 was estimated.

(Formula 1)
PCE (%) = [Jsc (mA / cm ² ) × Voc (V) × FF (%)] / 100 mW / cm ²
The conversion efficiency as the initial cell characteristics of the obtained solar cells 1 to 13 was measured, and then the conversion after the forced deterioration test in which the degree of deterioration in performance over time was stored for 1000 hours in a temperature 60 ° C., humidity 90% RH environment. Five-level rank evaluation was performed based on the efficiency remaining rate.

(5-level rank evaluation)
Ratio of conversion efficiency / initial conversion efficiency after forced degradation test 5: 90% or more 4: 70% or more, less than 90% 3: 40% or more, less than 70% 2: 20% or more, less than 40% 1: less than 20% Note that rank 3 or higher can withstand practical use.

  The obtained results are shown in Table 2.

  From Table 2, it is clear that the solar cells 2 to 13 of the present invention are all excellent in energy conversion efficiency after forced deterioration as compared with the comparative solar cell 1.

Claims (9)

After the step of applying a coating liquid containing polysilazane on the surface of the substrate to prepare a coating film, the step of drying the coating film, and the step of irradiating the coating film with vacuum ultraviolet light, the coating film In the method for producing a barrier film having a step of forming a barrier layer by modifying
After the step of drying the coating film , and before the step of irradiating the vacuum ultraviolet light and at least one of the step of irradiating the vacuum ultraviolet light, the step of performing a surface treatment,
Step of performing the surface treatment, a manufacturing method of the barrier film, wherein step der Rukoto blowing gas mainly containing gas which does not absorb vacuum ultraviolet light to the coating film. The method for producing a barrier film according to claim 1, wherein a content of the gas that does not absorb the vacuum ultraviolet light in the gas is 95% by volume or more. The method for producing a barrier film according to claim 2, wherein the content of the gas that does not absorb the vacuum ultraviolet light in the gas is 99% by volume or more. The method for producing a barrier film according to claim 3, wherein the content of the gas that does not absorb the vacuum ultraviolet light in the gas is 100% by volume. The method for producing a barrier film according to claim 1, wherein the gas that does not absorb vacuum ultraviolet light is nitrogen. The method for producing a barrier film according to any one of claims 1 to 5 , wherein the vacuum ultraviolet light is irradiation light from a xenon excimer lamp. Barrier film characterized by being manufactured by the method for producing a barrier film according to any one of claims 1-6. An organic photoelectric conversion element comprising the barrier film according to claim 7 . A solar cell comprising the organic photoelectric conversion device according to claim 8 .