Electronic device, production method thereof, imaging method and imaging device

Abstract

An electronic device is provided, which includes: a carrier; a charge transport layer including a charge transport material or a sensitizing dye electrode layer including a sensitizing dye, wherein the charge transport layer or the sensitizing dye electrode layer is disposed on or above the carrier; and a metal oxide layer disposed on or above the charge transport layer or the sensitizing dye electrode layer, wherein the metal oxide layer includes a p-type semiconductor metal oxide and silica or metal oxide particles, and wherein the amount of silica or metal oxide particles included in the metal oxide layer is 0.5% by mass or more but 1.5% by mass or less relative to the metal oxide layer.

Description

Technical Field

[0001] The present disclosure relates to an electronic device, a method of manufacturing the electronic device, an imaging method, and an imaging apparatus. Background Art

[0002] In recent years, photoelectric conversion devices including organic semiconductors have been developed and are commercially available.

[0003] Currently, widely available photoelectric conversion devices such as electrophotographic photoreceptors are mostly organic electronic devices formed of organic materials. However, organic electronic devices have the following problems: compared with inorganic electronic devices, the service life of organic electronic devices is shorter. One of the reasons for the short service life is the poor gas barrier property caused by the organic materials included in the organic electronic devices. Compared with the dense film of inorganic materials, the organic material resin film has many gaps. Therefore, a food wrapping material (such as polypropylene (PP)) is laminated with an aluminum layer to enhance the weather resistance of the contents.

[0004] As an organic solar cell that is lower in cost compared with a silicon-based solar cell, a dye-sensitized solar cell including an organic sensitizing dye has been developed.

[0005] However, since the dye-sensitized solar cell includes an organic sensitizing dye as an organic material, compared with a silicon-based solar cell, the applied materials tend to deteriorate due to temperature, humidity, and gases (for example, oxygen, ozone, NOx, ammonia), and thus the functions of the dye-sensitized solar cell tend to degrade. Therefore, the dye-sensitized solar cell has a problem of poor durability compared with a silicon-based solar cell.

[0006] In display elements such as organic electroluminescence (EL) elements, light-emitting diode display elements, liquid crystal display elements, and electrophoretic ink display elements, a display element, such as an organic EL layer sandwiched between a positive electrode and a negative electrode, is laminated on a substrate. Compared with a liquid crystal display device, an organic EL display device has a wide viewing angle and a high response speed, and thus is expected to be a next-generation display device due to the light-emitting diversity of the organic material.

[0007] As a method of forming an organic EL element, in view of productivity and cost, a forming method using coating is adopted. In addition, the organic EL element tends to deteriorate due to exposure to heat or gases (such as moisture and oxygen). Therefore, there is a problem of a short service life of the organic EL element.

[0008] An attempt has been made to improve the gas barrier property to extend the service life of organic electronic devices such as electrophotographic photoreceptors for printers, dye-sensitized solar cells, and organic EL elements. However, the number of processes is large, which has an adverse effect on the organic electronic devices, and thus there is room for improvement in the balance between cost and durability.

[0009] As an electrophotographic photoreceptor having excellent abrasion resistance and image property stability, for example, an electrophotographic photoreceptor including a protective layer including p-type semiconductor particles treated with a surface treatment agent has been proposed (see, for example, PTL 1).

[0010] As an organic EL element having a long service life, improved efficiency, and low driving voltage, for example, an organic EL element has been proposed in which the organic hole transport layer of the organic EL element is replaced with an inorganic p-type semiconductor (see, for example, PTL 2).

[0011] In addition, a laminate has been proposed in which particulate materials such as ceramic materials and metal materials having a size of 100 μm or less form a film on a substrate by aerosol deposition to form a polycrystalline brittle material layer (see, for example, PTL 3).

[0012] The gas barrier property can be improved by providing a metal oxide including a p-type semiconductor as a surface layer. For the film formation of the metal oxide, aerosol deposition having excellent bulk productivity is suitably applied. When the fluidity of the raw material powder is poor, the film formation of the metal oxide tends to be uneven and the processability is insufficient, so mass production as an industrial product is not achievable.

[0013] Citation List

[0014] Patent Documents

[0015] PTL 1: Japanese Patent No. 5664538

[0016] PTL 2: Japanese Unexamined Patent Application Publication No. 2000-150166

[0017] PTL 3: Japanese Unexamined Patent Application Publication No. 2008-201004 Summary of the Invention

[0018] Technical Problem

[0019] An object of the present disclosure is to provide an electronic device that can suppress uneven film formation of a metal oxide layer and has a high uniformity in the thickness of the metal oxide layer.

[0020] Problem-Solving Means

[0021] According to one aspect of the present disclosure, an electronic device includes: a carrier; a charge transport layer including a charge transport material or a sensitizing dye electrode layer including a sensitizing dye, wherein the charge transport layer or the sensitizing dye electrode layer is disposed on or above the carrier; and a metal oxide layer disposed on or above the charge transport layer or the sensitizing dye electrode layer, wherein the metal oxide layer includes a p-type semiconductor metal oxide and silica or metal oxide particles, and the amount of silica or metal oxide particles included in the metal oxide layer is 0.5% by mass or more but 1.5% by mass or less relative to the metal oxide layer.

[0022] Advantageous Effects of the Invention

[0023] The present disclosure can provide an electronic device that can suppress uneven film formation of the metal oxide layer and has high uniformity in the thickness of the metal oxide layer. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 Figure 1 is a schematic structural diagram of an example of an imaging device illustrating the present disclosure.

[0025] Figure 2 Figure 2 is a schematic structural diagram of another example of an imaging device illustrating the present disclosure.

[0026] Figure 3 Figure 3 is a schematic structural diagram of an example of an imaging unit in an imaging device illustrating the present disclosure.

[0027] Figure 4 Figure 4 is a schematic structural diagram of another example of an imaging device illustrating the present disclosure.

[0028] Figure 5 Figure 5 is a schematic structural diagram of another example of an imaging device illustrating the present disclosure.

[0029] Figure 6 Figure 6 is a cross-sectional view of an example of an electronic device (electrophotographic photoreceptor) illustrating the present disclosure.

[0030] Figure 7 Figure 7 is a cross-sectional view of an example of an electronic device (solar cell) illustrating the present disclosure.

[0031] Figure 8 Figure 8 is a cross-sectional view of an example of an electronic device (organic EL element) illustrating the present disclosure.

[0032] ​​​​​​​​​​​​​​​​​Figure 9 Figure 9 It is a schematic structural diagram of an example of an aerosol deposition apparatus for forming a metal oxide layer according to the present disclosure.

[0033] Figure 10A Figure 10A It is a photograph of an example of a film-forming ceramic.

[0034] Figure 10B Figure 10B It is a photograph of an example of a film-forming ceramic.

[0035] Figure 10C Figure 10C It is a photograph of an example of a film-forming ceramic. Detailed Description

[0036] <Electronic Device>

[0037] The electronic device of the present disclosure includes: a carrier; a charge transport layer including a charge transport material or a sensitizing dye electrode layer including a sensitizing dye, wherein the charge transport layer or the sensitizing dye electrode layer is disposed on or above the carrier; and a metal oxide layer disposed on or above the charge transport layer or the sensitizing dye electrode layer. The metal oxide layer includes a p-type semiconductor metal oxide and silica or metal oxide particles. The amount of silica or metal oxide particles included in the metal oxide layer is 0.5% by mass or more but 1.5% by mass or less relative to the metal oxide layer.

[0038] The electronic device is not particularly limited and can be appropriately selected according to the intended purpose. Examples of the electronic device include devices such as electrophotographic photoreceptors, solar cells, organic electroluminescence (EL) elements, transistors, integrated circuits, laser diodes, and light-emitting diodes.

[0039] In addition, the electronic device of the present disclosure is completed based on the following insight. That is, there are cases where electronic devices known in the art may not have a high degree of uniformity in the thickness of the metal oxide layer (less thickness variation (fluctuations, variations)), where film formation unevenness of the metal oxide layer is suppressed.

[0040] In the film formation by aerosol deposition known in the art using a metal oxide including a p-type semiconductor, when the fluidity of the raw material powder is poor, the formation of the metal oxide tends to be uneven and the processability is insufficient, so mass production as an industrial product is not achievable.

[0041] ​​​​​​​The present disclosure includes a metal oxide layer on a charge transport layer or a sensitizing dye electrode layer, wherein the metal oxide layer includes a metal oxide and silica or metal oxide particles, and the metal oxide includes a p-type semiconductor. Accordingly, film formation unevenness of the metal oxide layer can be suppressed, and an electronic device having a highly uniform metal oxide layer thickness and suppressing film formation unevenness can be provided.

[0042] In the proposal of PTL 1 (Japanese Patent No. 5664538), the protective layer includes a ceramic as a p-type semiconductor, but the ceramic is not in the form of a film but in the form of particulate semiconductors. PTL 1's Figure 1 illustrates a conceptual diagram in which particulate semiconductors are dispersed in the protective layer. The form of the film here means Figure 10A 、 10B and the embodiment of the whitest surface layer seen in 10C.

[0043] PTL 2 (Japanese Unexamined Patent Application Publication No. 2000-150166) discloses a hole transport layer using an inorganic p-type semiconductor, but PTL 2 does not disclose that the hole transport layer includes silica.

[0044] In the proposal of PTL 3 (Japanese Unexamined Patent Application Publication No. 2008-201004), a dense polycrystalline brittle material layer formed of particles is formed, but PTL 3 does not disclose that the particles include silica.

[0045] <Metal Oxide Layer>

[0046] The metal oxide layer includes a p-type semiconductor metal oxide and silica or metal oxide particles. In the present disclosure, the p-type semiconductor metal oxide is preferably cuprite oxide.

[0047] <<Cuprite Oxide>>

[0048] The cuprite oxide (hereinafter may be referred to as "p-type semiconductor" or "p-type metal compound semiconductor") is not particularly limited and can be appropriately selected according to the intended purpose as long as the cuprite oxide has the function of a p-type semiconductor. Examples of the cuprite oxide include p-type metal oxide semiconductors, p-type metal compound semiconductors including monovalent copper, and other p-type metal compound semiconductors.

[0049] Examples of the p-type metal oxide semiconductors include: CoO, NiO, FeO, Bi2O3, MoO2, MoS2, Cr2O3, SrCu2O2, and CaO-Al2O3.

[0050] Examples of p-type metal compound semiconductors including monovalent copper include: CuI, CuInSe2, Cu2O, CuSCN, CuS, CuInS2, CuAlO, CuAlO2, CuAlSe2, CuGaO2, CuGaS2, and CuGaSe2.

[0051] Examples of other p-type metal compound semiconductors include: GaP, GaAs, Si, Ge, and SiC.

[0052] Among the examples listed above, copper aluminum oxides such as CuAlO and CuAlO2 are preferable in view of charge mobility and light transmittance.

[0053] <<Silicon dioxide>>

[0054] The silicon dioxide included in the metal oxide layer of the present disclosure can be appropriately synthesized for use, or can be selected from commercial products. Examples of commercial products include REOLOSIL ZD-30S (available from Tokuyama Corporation), HDKH-2000 (available from Wacker Asahikasei Silicone Co., Ltd.), and AEROSIL R976 and AEROSIL RA200HS (available from NIPPON AEROSIL CO., LTD.).

[0055] Silicon dioxide is preferably in the form of particles. The volume average particle diameter of the silicon dioxide particles is preferably 1 μm or more but 50 μm or less.

[0056] The average particle diameter of the silicon dioxide particles can be measured by a particle size distribution analyzer MT3300EX available from Microtrac BEL Corp. etc.

[0057] The amount of silicon dioxide included in the metal oxide layer is 0.5% by mass or more but 1.5% by mass or less, preferably 0.7% by mass or more but 1.3% by mass or less, relative to the metal oxide layer. When the amount of silicon dioxide is within the above range, film formation unevenness of the metal oxide layer can be suppressed, and an electronic device with highly uniform metal oxide layer thickness can be obtained.

[0058] <<Metal oxide particles>>

[0059] Examples of the metal oxide particles included in the metal oxide layer of the present disclosure include aluminum oxide, barium titanate, chromium oxide, copper oxide, iron oxide, magnesium oxide, manganese oxide, strontium titanate, tin oxide, titanium oxide, zinc oxide, and zirconium oxide.

[0060] The metal oxide particles can be appropriately synthesized for use or can be selected from commercial products. Examples of commercial products include alumina AKP-50 (available from SUMITOMO CHEMICAL COMPANY, LIMITED), alumina AKP-20 (available from SUMITOMO CHEMICAL COMPANY, LIMITED), alumina TM-DAR (available from TAIMEI CHEMICALS CO., LTD.), and zinc oxide SF-10 (available from SAKAI CHEMICAL INDUSTRY CO., LTD.).

[0061] The volume average particle diameter of the metal oxide particles is preferably 1 / 100 to 1 / 10 of the size of the metal oxide particles (base particles) having a p-type semiconductor, more preferably 1 μm or more but 3 μm or less.

[0062] The volume average particle diameter of the metal oxide particles can be measured by the same method as the measurement method of the silica particles.

[0063] The amount of the metal oxide particles included in the metal oxide layer is 0.5% by mass or more but 1.5% by mass or less, preferably 0.7% by mass or more but 1.3% by mass or less with respect to the metal oxide layer. When the amount of the metal oxide particles is within the above range, film formation unevenness of the metal oxide layer can be suppressed, and an electronic device with highly uniform thickness of the metal oxide layer can be obtained.

[0064] <<Thickness of the metal oxide layer>>

[0065] In the present disclosure, the average thickness of the metal oxide layer is preferably 1.2 μm or more but 1.8 μm or less. More preferably, the average thickness of the metal oxide layer is 1.2 μm or more but 1.8 μm or less, and the standard deviation of the thickness of the metal oxide layer is 0.07 μm or less.

[0066] In the case of an electrophotographic photoreceptor as an embodiment of the electrochromic device of the present disclosure, for example, the thickness of the photoreceptor is measured at 5 points of a cylindrical photoreceptor drum having a length of 380 mm and an outer diameter of 100 mm, where these 5 points are obtained at intervals of 50 mm in the length direction from a position 100 mm from the edge of the photoreceptor drum to a position 300 mm from its edge. The above thickness measurement is performed on 20 photoreceptor drums to obtain a total of 100 thickness data points. The thickness measurement is performed by the method using light interference as described in Japanese Patent No. 5521607. The standard deviation is determined and the thickness is determined from the average value of the obtained data.

[0067] When the average thickness of the metal oxide layer is 1.2 microns or more but less than 1.8 microns, it is advantageous because a high-quality printed image with an excellent balance between abrasion resistance and static electricity and a long service life can be formed. In addition, when the standard deviation of the thickness of the metal oxide layer is 0.07 microns or less, it is advantageous because the printed image has excellent gradation reproducibility, which affects the appearance of printed images of human skin or landscapes.

[0068] <<Process Capability>>

[0069] In addition, the process capability index Cpk is calculated from the obtained average thickness and standard deviation according to the following equations (1) to (3). The process capability index is a value that evaluates the degree of deviation of the arithmetic mean X of the thickness from the standard median. A larger Cpk means a higher ability to produce electronic devices with stable quality.

[0070] [Mathematics 1]

[0071] Cpk = Cp(1 - K) (1)

[0072] [Mathematics 2]

[0073]

[0074] [Mathematics 3]

[0075]

[0076] In the above equations, USL is the upper limit value of the standard, LSL is the lower limit value of the standard, X is the arithmetic mean of the thickness, and σ is the standard deviation. In addition, Cp is the comparison between 6σ and the standard width, and 6σ represents the variation in the film-forming process.

[0077] <Production of Metal Oxide Layer>

[0078] The production method (film-forming method) of the metal oxide layer is not particularly limited, and can be appropriately selected from generally used inorganic material film-forming methods. Examples thereof include evaporation methods, liquid-phase growth methods, and solid-phase growth methods.

[0079] Evaporation methods are classified, for example, into physical vapor deposition methods (PVD) and chemical vapor deposition methods (CVD).

[0080] Examples of physical vapor deposition methods include vacuum evaporation, electron beam evaporation, laser ablation, laser ablation MBE, MOMBE, reactive evaporation, ion plating, cluster ion beam, glow discharge sputtering, ion beam sputtering, and reactive sputtering.

[0081] Examples of chemical vapor deposition methods include thermal CVD, MOCVD, RF plasma CVD, ECR plasma CVD, photo CVD, and laser CVD.

[0082] Examples of liquid phase growth methods include LPE, electroplating, electroless plating, and coating.

[0083] Examples of solid phase growth methods include SPE, recrystallization, graphoepitaxy, LB method, sol-gel method, and aerosol deposition (AD).

[0084] Among the examples listed above, AD is preferred because AD does not adversely affect the uniform film formation of a relatively large area film such as an electrophotographic photoreceptor or the properties of the electrophotographic photoreceptor.

[0085] <<Aerosol Deposition (AD)>>

[0086] Aerosol deposition (AD) is a technique in which pre-prepared particles or microparticles are mixed with a gas to form an aerosol and the aerosol is ejected through a nozzle onto a film-forming target (substrate) to form a film.

[0087] As a characteristic of AD, film formation can be carried out in a room temperature environment, and film formation can be carried out while the crystal structure of the raw material remains substantially the same. Therefore, AD is suitable for film formation on electronic devices (especially electrophotographic photoreceptors).

[0088] A method of forming a metal oxide layer by aerosol deposition will be described.

[0089] In this method, use Figure 9 An exemplary aerosol deposition apparatus. Figure 9 An exemplary gas cylinder 110 stores an inert gas for generating an aerosol. The gas cylinder 110 is connected to an aerosol generator 130 through a pipe 120a, and the pipe 120a is directed inside the aerosol generator 130. A certain amount of particles 200 formed of a metal oxide or a semiconductor compound are placed inside the aerosol generator 130. Another pipe 120b connected to the aerosol generator 130 is coupled to a spray nozzle 150 inside a film-forming chamber 140.

[0090] In the present disclosure, particles 200 formed of a p-type semiconductor metal oxide and silica are introduced into the aerosol generator 130 to generate an aerosol, and the generated aerosol is guided to the nozzle 150 through the duct 120b. Optionally, an aerosol of the p-type semiconductor metal oxide and silica is generated by an aerosol generator (not illustrated) including the p-type semiconductor metal oxide and silica, and an aerosol of silica is generated by an aerosol generator (not illustrated) including silica, and the generated aerosols are transmitted through ducts and sprayed at high speed from two nozzles toward the substrate, respectively.

[0091] Inside the film formation chamber 140, the substrate 160 is held by the substrate holder 170 to face the spray nozzle 150. As the substrate 160, a cylindrical conductive carrier or an electronic device such as a photoreceptor, a solar cell, and an EL element can be used. An exhaust pump 180 for adjusting the degree of vacuum inside the film formation chamber 140 is connected to the film formation chamber 140 through the duct 120c.

[0092] Although not illustrated, the film formation apparatus for forming an electrode according to the present embodiment includes a system configured to laterally move the spray nozzle 150 at high speed while rotating the substrate holder 170 using the rotation unit 170a. By performing film formation by laterally moving the spray nozzle 150, a metal oxide layer having a desired area can be formed on the substrate 160.

[0093] During the process of forming the metal oxide layer, first, the compression valve 190 is closed to form a vacuum in the internal atmosphere from the film formation chamber 140 to the aerosol generator 130 using the exhaust pump 180. Next, the compression valve 190 is opened to introduce the gas inside the gas cylinder 110 into the aerosol generator 130 through the duct 120a, so that the particles 200 are dispersed inside the container. Thereby, an aerosol in a state where the particles 200 are dispersed in the gas is generated. The generated aerosol is sprayed at high speed from the nozzle 150 toward the substrate 160 through the duct 120b. When 0.5 seconds have elapsed in the state where the compression valve 190 is open, the compression valve 190 is closed for the next 0.5 seconds. Thereafter, the compression valve 190 is opened again, and the opening and closing of the compression valve 190 are repeated at a cycle of 0.5 seconds. The flow rate of the gas from the gas cylinder 110 is 5 L / min, the film formation duration is 1 hour, the degree of vacuum inside the film formation chamber 140 when the compression valve 190 is closed is about 10 Pa, and the degree of vacuum inside the film formation chamber 140 when the compression valve 190 is open is about 100 Pa.

[0094] The ejection speed of the aerosol is controlled by the shape of the nozzle 150, the length or inner diameter of the pipe 120b, the internal air pressure of the gas cylinder 110, or the amount of gas discharged by the exhaust pump 180 (the internal pressure of the film forming chamber 140). When the internal pressure of the aerosol generator 130 is tens of thousands of Pa, the internal pressure of the film forming chamber 140 is several tens to several hundreds of Pa, and the opening shape of the nozzle 150 is a circle with an inner diameter of 1 mm, for example, the ejection speed of the aerosol can be set to several hundred meters per second by the internal pressure difference between the aerosol generator 130 and the film forming chamber 140. When the internal pressure of the film forming chamber 140 is maintained in the range of 5 Pa to 100 Pa and the internal pressure of the aerosol generator 130 is maintained at 50,000 Pa, a metal oxide layer with a porosity of 5% to 30% can be formed. The average thickness of the metal oxide layer is preferably adjusted to the range of 0.1 micrometer to 10 micrometers - by adjusting the supply duration of the aerosol under the above conditions.

[0095] The average thickness of the metal oxide layer can be adjusted to a suitable thickness for each electronic device.

[0096] In the case of an electrophotographic photoreceptor as an example of an electronic device, as a condition for the best mode of obtaining the durability and high printing quality of the electronic device, the preferred average thickness of the metal oxide layer is 1.2 micrometers to 1.8 micrometers.

[0097] The particles 200 that obtain kinetic energy through acceleration in the aerosol are crushed into the substrate 160, and the particles 200 are finely pulverized by the collision energy. When the pulverized particles are combined with the substrate 160 and the pulverized particles are combined with each other, the metal oxide layer is sequentially formed on the charge transport layer.

[0098] The film formation is performed by several patterning using a line pattern or the rotation of the photosensitive drum. By scanning the substrate (drum) holder 170 or the ejection nozzle 150 in the longitudinal direction and the transverse direction on the substrate 160, a metal oxide layer with a desired area is formed.

[0099] <Electrophotographic photoreceptor>

[0100] An embodiment of the electronic device of the present disclosure is an electrophotographic photoreceptor.

[0101] The electrophotographic photoreceptor (hereinafter may be referred to as "photoreceptor") includes a conductive carrier as a carrier; a charge transport layer including a charge transport material, wherein the charge transport layer is disposed on or above the conductive carrier; and a metal oxide layer disposed on or above the charge transport layer. The electrophotographic photoreceptor further includes a charge generation layer and may further include other layers as needed, such as an intermediate layer and a protective layer.

[0102] As this metal oxide layer, the above-mentioned metal oxide layer is appropriately used.

[0103] Note that a layer in which a charge generation layer and a charge transport layer are sequentially laminated may be referred to as a photosensitive layer.

[0104] Examples in which the electronic device is an electrophotographic photoreceptor will be described below, but the examples of the electronic device are not limited to electrophotographic photoreceptors, and the present disclosure can also be applied to other electronic devices.

[0105] Reference will be made to Figure 6 describe the structure of the electronic device 10A as an electrophotographic photoreceptor. Figure 6 is a cross-sectional view showing an example of an electrophotographic photoreceptor.

[0106] Figure 6 Embodiments of the electrophotographic photoreceptor are exemplified. In Figure 6 In the embodiment, the electrophotographic photoreceptor 10A includes an intermediate layer 52, a charge generation layer 53, a charge transport layer 54, a silicone hard coat 55, and a metal oxide layer 56 that are provided on the conductive support 51 in this order. The intermediate layer 52 and the silicone hard coat 55 may be arbitrarily omitted.

[0107] <<Support (Conductive Support)>>

[0108] The conductive support is not particularly limited and may be appropriately selected according to the intended purpose as long as the conductive support exhibits a volume resistivity of 10 10 ohm·cm or less. Examples thereof include: a film or a cylindrical plastic or paper coated with a metal (e.g., aluminum, nickel, chromium, nickel-chromium alloy, copper, silver, gold, platinum, and iron) or an oxide (e.g., tin oxide and indium oxide) by evaporation or sputtering; and a tube obtained by forming a plate such as aluminum, aluminum alloy, nickel, or stainless steel into a tube by methods such as drawing ironing, impact ironing, extruded ironing, extruded drawing, and machining, and then performing surface treatments such as machining, superfinishing, and polishing.

[0109] <<Intermediate Layer>>

[0110] The electrophotographic photoreceptor may include an intermediate layer provided between the conductive support and the photosensitive layer. The intermediate layer is provided for the purpose of improving adhesion, preventing moiré, improving the coatability of the upper layer, and preventing charge injection from the conductive support.

[0111] The intermediate layer generally includes a resin as a main component. Since a photosensitive layer is applied on the intermediate layer, the resin used in the intermediate layer is preferably a thermosetting resin that is poorly soluble in organic solvents. Among thermosetting resins, polyurethane, melamine resin, and alkyd-melamine resin are more preferably used as the resin for the intermediate layer because a variety of the resins listed above achieve the above purposes.

[0112] Examples of organic solvents include tetrahydrofuran, cyclohexanone, dioxane, dichloroethane, and methyl ethyl ketone. The coating material for the intermediate layer can be prepared by appropriately diluting the resin with an organic solvent.

[0113] In addition, to adjust conductivity or prevent moiré patterns, particles of metals, metal oxides, etc. can be added to the intermediate layer. The metal oxide is preferably titanium oxide or zinc oxide. The coating material for the intermediate layer can be prepared as follows: a dispersion liquid is prepared by dispersing the particles in an organic solvent using a ball mill, grinder, sand mill, etc., and the dispersion liquid and the resin component are mixed.

[0114] Examples of the production method (film-forming method) of the intermediate layer include: a method of forming a film by applying the coating material on a conductive carrier by dip coating, spray coating, bead coating, etc., and a method of optionally heating the obtained film to cure it. The average thickness of the intermediate layer is usually appropriately about 2 μm to about 20 μm. When the residual potential of the photoreceptor accumulates excessively, the average thickness of the intermediate layer can be less than 3 μm.

[0115] <<Photosensitive layer>>

[0116] The photosensitive layer of the photoreceptor is a laminated photosensitive layer in which a charge generation layer and a charge transport layer are laminated in this order.

[0117] <<Charge generation layer>>

[0118] The charge generation layer is a part of the laminated photosensitive layer. The charge generation layer having the function of generating charges upon exposure includes a charge generation material as a main component and may further include a binder resin as needed. Examples of charge generation materials include inorganic charge generation materials and organic charge generation materials.

[0119] Examples of inorganic charge generation materials include crystalline selenium, amorphous selenium, selenium-tellurium, selenium-tellurium-halogen, selenium-arsenic compounds, and amorphous silicon. As amorphous silicon, amorphous silicon in which dangling bonds are terminated by hydrogen atoms or halogen atoms, and amorphous silicon doped with boron atoms, phosphorus atoms, etc. are preferably used.

[0120] As the organic charge generation material, known materials can be used. Examples thereof include: metal phthalocyanines such as titanyl phthalocyanine and gallium chloro phthalocyanine; metal-free phthalocyanines; azulium salt pigments; squarylium pigments; symmetric or asymmetric azo pigments having a carbazole skeleton; symmetric or asymmetric azo pigments having a triphenylamine skeleton; symmetric or asymmetric azo pigments having a fluorenone skeleton; and perylene-based pigments. Among the examples listed above, metal phthalocyanines, symmetric or asymmetric azo pigments having a fluorenone skeleton, symmetric or asymmetric azo pigments having a triphenylamine skeleton, and perylene-based pigments are preferred because of their extremely high quantum efficiency of charge generation. The charge generation materials listed above can be used alone or in combination.

[0121] Examples of the binder resin include polyamide, polyurethane, epoxy resin, polyketone, polycarbonate, polyacrylate, silicone resin, acrylic resin, polyvinyl butyral, polyvinyl formal, polyvinyl ketone, polystyrene, poly-N-vinylcarbazole, and polyacrylamide.

[0122] Among the examples listed above, polyvinyl butyral is commonly used and effective. The binder resins listed above can be used alone or in combination.

[0123] [[Method for Producing Charge Generation Layer]]

[0124] The method for producing the charge generation layer is roughly classified into a vacuum thin film formation method and a casting method of a solution dispersion system.

[0125] Examples of the vacuum thin film formation method include vacuum evaporation, glow discharge decomposition, ion plating, sputtering, reactive sputtering, and chemical vapor deposition (CVD). The methods listed above are applicable to the production of a layer formed of an inorganic charge generation material or an organic charge generation material.

[0126] As a method for producing the charge generation layer by the casting method, an inorganic charge generation material or an organic charge generation material is optionally dispersed in an organic solvent together with a binder resin by a ball mill, a grinder, a sand mill, etc. to prepare a dispersion, and the dispersion is appropriately diluted and the resulting product is coated.

[0127] Examples of the organic solvent include tetrahydrofuran, cyclohexanone, dioxane, dichloroethane, and methyl ethyl ketone. Among the examples listed above, methyl ethyl ketone, tetrahydrofuran, and cyclohexanone are preferred because the above solvents have a lower environmental load compared with chlorobenzene, dichloromethane, toluene, and xylene.

[0128] Coating can be performed by dip coating, spraying, bead coating, etc.

[0129] The average thickness of the charge generation layer is preferably from 0.01 μm to 5 μm.

[0130] When the reduction of the residual potential and high sensitivity are important, an increase in the thickness of the charge generation layer generally improves the above properties. On the other hand, a thick charge generation layer generally deteriorates the chargeability such as charge retention or the formation of space charge. To balance the above advantages and disadvantages, the average thickness of the charge generation layer is more preferably from 0.05 μm to 2 μm.

[0131] In addition, low molecular weight compounds such as antioxidants, plasticizers, lubricants, UV absorbers, and leveling agents can be optionally added to the charge generation layer. The compounds listed above can be used alone or in combination. When the low molecular weight compounds and leveling agents are used in combination with other components of the charge generation layer, the sensitivity generally deteriorates. Therefore, the amount of the low molecular weight compounds and leveling agents is preferably from 0.1 phr to 20 phr in total, more preferably from 0.1 phr to 10 phr. The amount of the leveling agent used is preferably from 0.001 phr to 0.1 phr.

[0132] <<Charge transport layer>>

[0133] The charge transport layer is a part of the laminated photosensitive layer and has a function of injecting and transporting the charges generated in the charge generation layer to neutralize the surface charges of the charged photoreceptor. The charge transport layer includes a charge transport material and a binder component that binds the charge transport material as main components.

[0134] The charge transport material includes an electron transport material and a hole transport material.

[0135] Examples of the electron transport material include electron-accepting materials such as asymmetric biphenylquinone derivatives, fluorene derivatives, and naphthalimide derivatives. The electron transport materials listed above can be used alone or in combination.

[0136] As the hole transport material, an electron-donating material is preferably used. Examples thereof include oxazole derivatives, oxadiazole derivatives, imidazole derivatives, triphenylamine derivatives, butadiene derivatives, 9-(p-diethylaminostyryl)anthracene, 1,1-bis-(4-dibenzylaminophenyl)propane, styryl anthracene, styryl pyrazoline, phenylhydrazone, α-phenylstilbene derivatives, thiazole derivatives, triazole derivatives, fenadine derivatives, acridine derivatives, benzofuran derivatives, benzimidazole derivatives, and thiophene derivatives. The hole transport materials listed above can be used alone or in combination.

[0137] Examples of the binder component include thermoplastic or thermosetting resins such as polystyrene, polyester, polyethylene, polyacrylate, polycarbonate, acrylic resin, silicone resin, fluororesin, epoxy resin, melamine resin, urethane resin, phenolic resin, and alkyd resin. Among the examples listed above, polystyrene, polyester, polyacrylate, and polycarbonate are effectively used as the binder component of the charge transport component because many of them exhibit superior charge transport properties.

[0138] When an electrically inert polymer compound is used for modifying the charge transport layer, cardo polymer type polyesters having a large skeleton such as fluorene, polyesters (e.g., polyethylene terephthalate and polyethylene naphthalate), polycarbonates in which the phenolic component of bisphenol polycarbonate such as type C polycarbonate is substituted with an alkyl group at the 3,3'-position, polycarbonates in which the gem-methyl group of bisphenol A is substituted with a long-chain alkyl group having 2 or more carbon atoms, polycarbonates having a biphenyl or diphenyl ether skeleton, polycaprolactone, polycarbonates having a long-chain alkyl skeleton such as polycaprolactone (e.g., disclosed in Japanese Unexamined Patent Application Publication No. 07-292095), acrylic resin, polystyrene, hydrogenated butadiene, etc. are effective.

[0139] In this specification, the term "electrically inert polymer compound" means a polymer compound that does not have a chemical structure exhibiting photosensitivity such as a triarylamine structure. When such a resin is used in combination with a binder resin as an additive, its amount is preferably 50 mass% or less with respect to the total solid content of the charge transport layer in view of the limitations related to light attenuation sensitivity.

[0140] When using a charge transport material, the amount of the charge transport material is generally preferably 40 phr to 200 phr, more preferably 70 phr to 100 phr. It is preferable to use a copolymer in which the resin component is copolymerized in an amount of 0 parts by mass to 200 parts by mass, preferably about 80 parts by mass to about 150 parts by mass, with respect to 100 parts by mass of the charge transport component.

[0141] The charge transport layer can be formed by dissolving or dispersing a mixture or copolymer including a charge transport component and a binder component as main components in an appropriate solvent to prepare a charge transport layer coating material, and applying and drying the coating material. As the coating method, dip coating, spray coating, ring coating, roll coater coating, gravure coating, nozzle coating, screen printing, etc. can be adopted.

[0142] Examples of the dispersion solvent used when preparing the charge transport layer coating material include: ketones such as methyl ethyl ketone, acetone, methyl isobutyl ketone, and cyclohexanone; ethers such as dioxane, tetrahydrofuran, and ethyl cellosolve; aromatic hydrocarbons such as toluene and xylene; halogenated compounds such as chlorobenzene and dichloromethane; and esters such as ethyl acetate and butyl acetate. Among the examples listed above, methyl ethyl ketone, tetrahydrofuran, and cyclohexanone are preferred because the solvents have a lower environmental load compared to chlorobenzene, dichloromethane, toluene, and xylene. The solvents listed above can be used alone or in combination.

[0143] To ensure the sensitivity and chargeability required during practice, the average thickness of the charge transport layer is preferably from 10 μm to 40 μm, more preferably from 15 μm to 30 μm.

[0144] In addition, low molecular weight compounds such as antioxidants, plasticizers, lubricants, and UV absorbers, as well as leveling agents - which will be described below - can be optionally added to the charge transport layer. When the low molecular weight compounds and leveling agents are used in combination with other components of the charge transport layer, the sensitivity generally deteriorates. Therefore, the amount of the compounds listed above is generally from 0.1 phr to 20 phr, preferably from 0.1 phr to 10 phr. The amount of the leveling agent is suitably about 0.001 phr to about 0.1 phr.

[0145] <<Silicone hard coat>>

[0146] The silicone hard coat is formed by crosslinking an organosilicon compound having a hydroxyl group or a hydrolyzable group. The silicone hard coat can further include a catalyst, a crosslinking agent, an organosilica sol, a silane coupling agent, or a polymer such as an acrylic polymer as needed.

[0147] There is no specific limitation on the crosslinking and it can be appropriately selected according to the intended purpose. The crosslinking is preferably thermal crosslinking.

[0148] Examples of the organosilicon compound having a hydroxyl group or a hydrolyzable group include compounds having an alkoxysilyl group, partial hydrolysis condensates of compounds having an alkoxysilyl group, and mixtures thereof.

[0149] Examples of the compound having an alkoxysilyl group include: tetraalkoxysilanes such as tetraethoxysilane; alkyltrialkoxysilanes such as methyltriethoxysilane; and aryltrialkoxysilanes such as phenyltriethoxysilane.

[0150] Note that an epoxy group, a methacryloyl group, or a vinyl group can be introduced into any of the compounds listed above.

[0151] Partial hydrolysis condensates of compounds having alkoxysilyl groups can be prepared by any method known in the art, such as by adding a predetermined amount of water, catalyst, etc. to the compound having alkoxysilyl groups to react the mixture.

[0152] As raw materials for the silicone hard coat, commercial products can be used. Specific examples thereof include GR-COAT (available from Daicel Corporation), Glass Resin (available from OWENS CORNING JAPAN LLC.), heatless glass (available from OHASHI CHEMICAL INDUSTRIES LTD.), NSC (available from NIPPON FINE CHEMICAL CO., LTD.), glass stock solutions GO150SX and GO200CL (available from Fine Glass Technologies Co., Ltd.), and MKC silicate (available from Mitsubishi Chemical Corporation), which is a copolymer between an alkoxysilyl compound and an acrylic resin or a polyester resin, and silicate / acrylic varnish XP-1030-1 (available from DainipponShikizai Kogyo Co., Ltd.).

[0153] The thickness of the silicone hard coat is preferably 0.1 μm or more but 4.0 μm or less, more preferably 0.3 μm or more but 1.5 μm or less.

[0154] <<Metal oxide layer>>

[0155] The metal oxide layer of the electrophotographic photoreceptor and its production method are appropriately selected from the detailed description of the metal oxide layer of the electronic device of the present disclosure and its production method.

[0156] <Production method of electronic device>

[0157] The method for producing an electronic device according to the present disclosure is a method for producing an electronic device including: a carrier; a charge transport layer including a charge transport material or a sensitizing dye electrode layer including a sensitizing dye, wherein the charge transport layer or the sensitizing dye electrode layer is disposed on or above the carrier; and a metal oxide layer disposed on or above the charge transport layer or the sensitizing dye electrode layer. The method includes spraying a p-type semiconductor metal oxide and silica or metal oxide particles to form the metal oxide layer.

[0158] The method for spraying the p-type semiconductor metal oxide and silica or metal oxide particles is not particularly limited and can be appropriately selected according to the intended purpose. The method is preferably aerosol deposition.

[0159] <Imaging Device and Imaging Method>

[0160] The imaging device of the present disclosure includes an electronic device (electrophotographic photoreceptor). The imaging device further includes an electrostatic latent image forming unit and a developing unit, and may further include other units as needed.

[0161] The imaging method related to the present disclosure includes at least an electrostatic latent image forming step and a developing step, and may further include other steps as needed.

[0162] The imaging method is appropriately performed by the imaging device, the electrostatic latent image forming step is appropriately performed by the electrostatic latent image forming unit, the developing step is appropriately performed by the developing unit, and the above-mentioned other steps are appropriately performed by the above-mentioned other units.

[0163] <Embodiments of the Imaging Device>

[0164] The structural examples of the imaging device will be described below with reference to the drawings.

[0165] Figure 1 An example of the imaging device is illustrated. The charging device 12 is a unit configured to uniformly charge the surface of the electrophotographic photoreceptor 11. As the charging device 12, any known unit such as a corotron, scorotron, solid-state charger, and charging roller can be used. In view of power consumption reduction, the charging device 12 is preferably arranged to be in contact with or adjacent to the electrophotographic photoreceptor 11. To prevent contamination of the charging device 12, a charging system preferably provided adjacent to the electrophotographic photoreceptor 11 has an appropriate gap between the surface of the electrophotographic photoreceptor 11 and the charging device 12. Generally, the above charger can be used as the transfer device 16. As the transfer device 16, a combination of a transfer charger and a separation charger is effective.

[0166] The electrophotographic photoreceptor 11 is driven by the driving unit 1C. Charging performed by the charging device 12, image exposure performed by the exposure device 13, development and transfer performed by the transfer device 16, pre-cleaning exposure performed by the pre-cleaning exposure device 1B, cleaning performed by the cleaning device 17, and charge removal performed by the charge removal device 1A are repeatedly executed. The lubricant 3A, the coating brush 3B for coating the lubricant, and the coating blade 3C are arranged between the cleaning device 17 and the charging device 12 along the traveling direction of the electrophotographic photoreceptor 11, as Figure 1 illustrated.

[0167] In Figure 1 the light for pre-cleaning exposure is applied from the carrier side of the electrophotographic photoreceptor 11 (in this case, the carrier is light-transmissive).

[0168] The above-described electro-optical process is an example. For example, the pre-cleaning exposure is performed from the side of the carrier in Figure 1 , but the pre-cleaning exposure can also be performed from the side of the photosensitive layer. In addition, the application of the image exposure light and the charge elimination light can be performed from the side of the carrier. At the same time, the image exposure light, the pre-cleaning exposure light, and the charge elimination light are exemplified as the light irradiation steps. However, in addition to the light irradiation step, pre-transfer pre-exposure, pre-exposure of the image exposure, and other light irradiation steps known in the art can be performed to irradiate the electrophotographic photoreceptor with light.

[0169] In addition, the above-described imaging unit can be fixed and integrated with a copying machine, a fax machine, or a printer. Optionally, the imaging unit can be integrated with any of the above devices in the form of a processing cartridge. Various examples of the shape of the processing cartridge can be listed, but as a general example, Figure 2 the shape exemplified in

[0170] is listed. The electrophotographic photoreceptor 11 has a drum shape, but the electrophotographic photoreceptor 11 can be in the shape of a sheet or an endless belt.

[0171] Figure 3 Another example of an imaging device is exemplified. In the imaging device, a charging device 12, an exposure device 13, black (Bk), cyan (C), magenta (M), and yellow (Y) developing devices 14Bk, 14C, 14M, and 14Y, an intermediate transfer belt 1F as an intermediate transfer member, and a cleaning device 17 are sequentially provided on the outer periphery of the electrophotographic photoreceptor 11.

[0172] Note that Figure 3The letters (Bk, C, M, and Y) depicted represent the colors of the toner, and are appropriately omitted when necessary. Each color of the developing devices 14Bk, 14C, 14M, and 14Y can be independently controlled, and only the developing device for the color used for imaging is driven. The toner image formed on the electrophotographic photoreceptor 11 is transferred to the intermediate transfer belt 1F by the first transfer device 1D provided inside the intermediate transfer belt 1F.

[0173] The first transfer device 1D is arranged such that the first transfer device 1D can contact the electrophotographic photoreceptor 11, and the intermediate transfer belt 1F contacts the electrophotographic photoreceptor 11 only during the transfer operation. Imaging for each color is performed, and the toner images superposed on the intermediate transfer belt 1F are jointly transferred to the print medium 18 by the second transfer device 1E, and then fixed by the fixing device 19 to form an image. The second transfer device 1E is also arranged such that the second transfer device 1E can contact the intermediate transfer belt 1F, and contacts the intermediate transfer belt 1F only during the transfer operation.

[0174] In an imaging device of a transfer drum system, toner images of different colors electrostatically adsorbed to the transfer drum are sequentially transferred to the print medium, so there is a limitation that the imaging device of the transfer drum system cannot print on thick paper. Meanwhile, in an imaging device of an intermediate transfer system, as Figure 3 illustrated, toner images of different colors are superposed on the intermediate transfer member 1F. Therefore, there is no limitation on the print medium used. The above intermediate transfer system can be applied not only to the Figure 3 device illustrated, but also to the imaging devices of Figure 1 , 2 , 4, and 5 illustrated.

[0175] The lubricant 3A, the coating brush 3B for coating the lubricant, and the coating blade 3C are arranged between the cleaning device 17 and the charging device 12 with respect to the rotation direction of the electrophotographic photoreceptor 11, as Figure 3 illustrated.

[0176] Figure 4 Another example of an imaging device is illustrated. The imaging device uses four-color toner, namely yellow (Y), magenta (M), cyan (C), and black (Bk), and imaging units for each color are arranged in the imaging device. In addition, electrophotographic photoreceptors 11Y, 11M, 11C, and 11Bk for four colors are provided. Around the outer periphery of each electrophotographic photoreceptor 11Y, 11M, 11C, or 11Bk, a charging device 12Y, 12M, 12C, or 12Bk, an exposure device 13Y, 13M, 13C, or 13Bk, a developing device 14Y, 14M, 14C, or 14Bk, a cleaning device 17Y, 17M, 17C, or 17Bk, etc. are provided.

[0177] In addition, the transfer transfer belt 1G is held by the driving unit 1C. The transfer transfer belt 1G is a transfer material carrier that enters and exits each transfer position of the electrophotographic photoreceptors 11Y, 11M, 11C, and 11Bk arranged in a straight line. The transfer devices 16Y, 16M, 16C, and 16Bk are disposed at the transfer positions and face the electrophotographic photoreceptors 11Y, 11M, 11C, and 11Bk via the transfer transfer belt 1G, respectively.

[0178] Figure 4 The tandem system imaging device exemplified in includes electrophotographic photoreceptors 11Y, 11M, 11C, or 11Bk of each color, and toner images of all colors are sequentially transferred onto a print medium held on the transfer transfer belt 1G. Therefore, compared with a full-color imaging device including only one electrophotographic photoreceptor, the tandem system imaging device can output a full-color image at a significantly higher speed. The toner image developed on the print medium 18 serving as a transfer material is transferred from the position where the electrophotographic photoreceptor 11Bk and the transfer device 16Bk face each other to the fixing device 19, and the toner image is fixed on the print medium 18 by the fixing device 19.

[0179] In addition, the imaging device may have Figure 5 the structure in the exemplary embodiment. Specifically, the structure using the intermediate transfer belt 1F exemplified in may be adopted to replace the direct transfer system using the transfer transfer belt 1G exemplified in. Figure 5 In the example exemplified in, the imaging device includes electrophotographic photoreceptors 11Y, 11M, 11C, or 11Bk of each color, and toner images of all colors formed by the electrophotographic photoreceptors are sequentially transferred and laminated onto the intermediate transfer belt 1F by the primary transfer unit 1D serving as a first transfer unit. The intermediate transfer belt 1F is driven and supported by a driving unit including a roller 1C, thereby forming a full-color image. Figure 4 In the example exemplified in, the intermediate transfer belt 1F is further driven, and the full-color image carried thereon is transferred to the secondary transfer unit 1E serving as a second transfer device and the position of the roller arranged to face the secondary transfer unit 1E. Then, the full-color image is secondarily transferred onto the transfer material 18 by the secondary transfer unit 1E, thereby forming a desired image on the transfer material.

[0180] In Figure 5 the example exemplified in, the imaging device includes electrophotographic photoreceptors 11Y, 11M, 11C, or 11Bk of each color, and toner images of all colors formed by the electrophotographic photoreceptors are sequentially transferred and laminated onto the intermediate transfer belt 1F by the primary transfer unit 1D serving as a first transfer unit. The intermediate transfer belt 1F is driven and supported by a driving unit including a roller 1C, thereby forming a full-color image.

[0181] Next, the intermediate transfer belt 1F is further driven, and the full-color image carried thereon is transferred to the secondary transfer unit 1E serving as a second transfer device and the position of the roller arranged to face the secondary transfer unit 1E. Then, the full-color image is secondarily transferred onto the transfer material 18 by the secondary transfer unit 1E, thereby forming a desired image on the transfer material.

[0182] <Solar cell>

[0183] One embodiment of the electronic device of the present disclosure is a solar cell.

[0184] The solar cell includes a carrier, a sensitized dye electrode layer which includes a sensitized dye, and a metal oxide layer which is disposed on or above the sensitized dye electrode layer. The solar cell further includes a first electrode, a hole blocking layer, and a second electrode, and may further include other components as needed.

[0185] Examples in which the electronic device is a solar cell will be described below, but the electronic device is not limited to a solar cell and can be applied to other electronic devices.

[0186] The solar cell (electronic device) of the present disclosure will be described with reference to the accompanying drawings. Note that the present disclosure is not limited to the embodiments described below. The embodiments described below can be changed, for example, another embodiment can be adopted, or additions, corrections, or omissions can be made to the embodiments described below within the scope achievable by those skilled in the art, and any of the above embodiments are included in the scope of the present disclosure as long as the functions and effects of the present disclosure are presented.

[0187] The solar cell (electronic device) includes a substrate which serves as a carrier, a first electrode, a hole blocking layer, an electron transport layer, a sensitized dye electrode layer, a ceramic semiconductor film which serves as a metal oxide layer, and a second electrode.

[0188] Reference will be made to Figure 7 describe the structure of the electronic device 10B, which is a solar cell. Figure 7 is a cross-sectional view of an example of an example solar cell.

[0189] In Figure 7 In the example embodiment, a first electrode 2 is formed on a substrate 1 that serves as a carrier, a hole blocking layer 3 is formed on the first electrode 2, an electron transport layer is formed on the hole blocking layer 3, a photosensitizing material 5 is adsorbed on the electron transport material of the electron transport layer 4, and a metal oxide 6 is disposed between the first electrode 2 and a second electrode 7 opposite the first electrode 2. Further, in Figure 7 an example of a structure in which leads 8 and 9 are provided to electrically connect the first electrode 2 and the second electrode 7 is illustrated.

[0190] The metal oxide and the electron transport layer 4 may penetrate each other to partially infiltrate each other.

[0191] Details are described below.

[0192] <<Carrier (Substrate)>>

[0193] The substrate 1 that serves as a carrier is not particularly limited and can be selected from substrates known in the art. The substrate 1 is preferably a transparent material. Examples thereof include glass, a transparent plastic plate, a transparent plastic film, and an inorganic transparent crystal.

[0194] <First Electrode>

[0195] There is no specific limitation on the first electrode 2 as long as the first electrode 2 is a conductive material transparent to visible light. As the first electrode 2, electrodes known in the art can be used, such as general optoelectronic conversion elements and liquid crystal panels.

[0196] Examples of the material of the first electrode include indium tin oxide (hereinafter referred to as ITO), fluorine-doped tin oxide (hereinafter referred to as FTO), antimony-doped tin oxide (hereinafter referred to as ATO), indium zinc oxide, niobium titanium oxide, and graphene. The materials listed above can be used alone or in combination as a laminate.

[0197] The average thickness of the first electrode is preferably 5 nm to 10 μm, more preferably 50 nm to 1 μm.

[0198] In addition, in order to maintain a certain hardness, the first electrode is preferably disposed on a substrate 1 formed of a material transparent to visible light. As the substrate, for example, glass, a transparent plastic plate, a transparent plastic film, an inorganic transparent crystal, etc. are used.

[0199] A first electrode integrated with the substrate known in the art can be used. Examples thereof include FTO-coated glass, ITO-coated glass, zinc oxide: aluminum-coated glass, FTO-coated transparent plastic film, and ITO-coated transparent plastic film.

[0200] In addition, the first electrode can be a transparent electrode prepared by doping tin oxide or indium oxide with cations or anions having different valence states, and a metal electrode having a light-permeable structure such as a net or a strip disposed on a substrate such as a glass substrate.

[0201] The examples listed above can be used alone, or mixed, or laminated.

[0202] In addition, in order to reduce the resistance, a metal lead or the like can be used in combination.

[0203] Examples of the material of the metal lead include metals such as aluminum, copper, silver, gold, platinum, and nickel. The metal lead is disposed on the substrate by evaporation, sputtering, crimping, etc., and ITO or FTO is disposed thereon.

[0204] <<Hole blocking layer>>

[0205] There is no specific limitation on the material constituting the hole blocking layer 3 as long as the material is transparent to visible light and is an electron transport material. The material is particularly preferably titanium oxide.

[0206] The hole blocking layer is provided to suppress the reduction of power caused by the recombination (i.e., reverse electron transport) between holes in the electrolyte and electrons present on the electrode surface when the electrode contacts the electrolyte hole blocking layer. The above-mentioned effect of the hole blocking layer 3 is particularly prominent in the solid dye-sensitized solar cell. This is because, compared with the wet dye-sensitized solar cell using an electrolyte solution, the solid dye-sensitized solar cell using an organic hole transport material or the like has a high recombination (reverse electron transport) speed between holes in the hole transport material and electrons present on the electrode surface.

[0207] The method for forming the hole blocking layer is not specifically limited, but having a high internal resistance is important for preventing current loss due to indoor light. Therefore, the method for forming the hole blocking layer is also important. Examples thereof generally include a sol-gel method as a wet film formation. The sol-gel method may not be able to fully prevent current loss. Therefore, its method is more preferably dry film formation, such as sputtering, and dry film formation can provide a sufficiently high film density and can prevent current loss.

[0208] The purpose of forming the hole blocking layer is to prevent electronic contact between the first electrode 2 and the hole transport layer 6. The average thickness of the hole blocking layer is not specifically limited. The average thickness of the hole blocking layer is preferably 5 nm to 1 micrometer. In wet film formation, the average thickness is more preferably 500 nm to 700 nm. In dry film formation, the average thickness is more preferably 10 nm to 30 nm.

[0209] <<Electron Transport Layer>>

[0210] The solar cell includes a porous electron transport layer 4 disposed on the hole blocking layer 3. The electron transport layer may be a single layer or a multilayer.

[0211] The electron transport layer is formed of an electron transport material. As the electron transport material, semiconductor particles are preferably used.

[0212] In the case of multiple layers, dispersions each including semiconductor particles of different particle sizes may be applied to form multiple layers, or coatings each including different types of semiconductor particles or each having different resin or additive compositions may be provided to form multiple layers. When one coating cannot provide a sufficient average thickness, multilayer coating is effective.

[0213] As the average thickness of the electron transport layer increases, the amount of photosensitizing material carried per unit projected area increases overall, so the light capture rate increases. However, the diffusion length of the injected electrons increases, so the charge loss caused by recombination also increases. Therefore, the average thickness of the electron transport layer is preferably 100 nm to 100 microns.

[0214] There is no specific limitation on the semiconductor, and any semiconductor known in the art can be used as the semiconductor. Specific examples thereof include: elemental semiconductors such as silicon and germanium; compound semiconductors such as metal chalcogenides; and compounds having a perovskite structure.

[0215] Examples of metal chalcogenides include: oxides of titanium, tin, zinc, iron, tungsten, zirconium, hafnium, strontium, indium, cerium, yttrium, lanthanum, vanadium, niobium, and tantalum; sulfides of cadmium, zinc, lead, silver, antimony, and bismuth; selenides of cadmium and lead; and tellurides of cadmium.

[0216] Examples of other compound semiconductors include: phosphides of zinc, gallium, indium, and cadmium; gallium arsenide; copper indium selenide; and copper indium sulfide.

[0217] In addition, compounds having a perovskite structure are preferably strontium titanate, calcium titanate, sodium titanate, barium titanate, or potassium niobate.

[0218] Among the examples listed above, oxide semiconductors are preferred, and titanium oxide, zinc oxide, tin oxide, and niobium oxide are particularly preferred. The examples listed above can be used alone or in combination as a mixture. There is no specific limitation on the crystal type of the semiconductors listed above. The crystal type can be single crystal, polycrystal, or amorphous.

[0219] There is no specific limitation on the average particle size of the primary particles of the semiconductor particles. The average particle size is preferably 1 nm to 100 nm, more preferably 5 nm to 50 nm.

[0220] In addition, due to the effect of scattering incident light, the efficiency can be improved by mixing or laminating semiconductor particles having a larger average particle size. In this case, the average particle size of the semiconductor is preferably 50 nm to 500 nm.

[0221] There is no specific limitation on the production method of the electron transport layer. The production methods include methods of forming a thin film in a vacuum, such as sputtering and wet film-forming methods.

[0222] In view of production cost, the wet film-forming method is particularly preferred. A method is preferred in which a paste in which semiconductor particle powder or sol is dispersed is prepared and the paste is applied to a collecting electron electrode substrate.

[0223] When the wet film-forming method is adopted, there is no specific limitation on the coating method, and coating can be performed according to any method known in the art. Coating can be carried out in various ways, such as dip coating, spray coating, wire bar coating, spin coating, roll coating, doctor blade coating, gravure coating, and wet printing methods (e.g., relief printing, offset printing, gravure printing, intaglio printing, rubber plate printing, and screen printing).

[0224] When forming a dispersion of semiconductor particles by mechanical pulverization or using a grinder, the dispersion is formed by dispersing at least individual semiconductor particles or a mixture including semiconductor particles and a resin in water or an organic solvent. Examples of the resin used include the following polymers or copolymers: vinyl compounds such as styrene, vinyl acetate, acrylate, and methacrylate; silicone resin; phenoxy resin; polysulfone resin; polyvinyl butyral resin; polyvinyl formal resin; polyester resin; cellulose ester resin; cellulose ether resin; urethane resin; phenolic resin; epoxy resin; polycarbonate resin; polyacrylate resin; polyamide resin; and polyimide resin.

[0225] Examples of the solvent for dispersing semiconductor particles include: water; alcohol solvents such as methanol, ethanol, isopropyl alcohol, and α-terpineol; ketone solvents such as acetone, methyl ethyl ketone, and methyl isobutyl ketone; ester solvents such as ethyl formate, ethyl acetate, and n-butyl acetate; ether solvents such as diethyl ether, dimethoxyethane, tetrahydrofuran, dioxolane, and dioxane; amide solvents such as N,N-dimethylformamide, N,N-dimethylacetamide, and N-methyl-2-pyrrolidone; halogenated hydrocarbon solvents such as dichloromethane, chloroform, bromoform, methyl iodide, dichloroethane, trichloroethane, trichloroethylene, chlorobenzene, o-dichlorobenzene, fluorobenzene, bromobenzene, iodobenzene, and 1-chloronaphthalene; and hydrocarbon solvents such as n-pentane, n-hexane, n-octane, 1,5-hexadiene, cyclohexane, methylcyclohexane, cyclohexadiene, benzene, toluene, o-xylene, m-xylene, p-xylene, ethylbenzene, and isopropylbenzene. The examples listed above can be used alone or in combination.

[0226] The dispersion of semiconductor particles or the paste of semiconductor particles obtained by a sol-gel method or the like may include an acid (e.g., hydrochloric acid, nitric acid, and acetic acid), a surfactant (e.g., polyoxyethylene(10) octylphenyl ether), and a chelating agent (e.g., acetylacetone, 2-aminoethanol, and ethylenediamine) to prevent particle re-aggregation.

[0227] In addition, adding a thickening agent is also effective for improving the film-forming property. Examples of the thickening agent include: polymers such as polyethylene glycol and polyvinyl alcohol; and ethyl cellulose.

[0228] After applying semiconductor particles, the particles are brought into electrical contact with each other, and preferably fired, microwave irradiated, electron beam irradiated, or laser irradiated to improve the film strength or adhesion to the substrate. The examples listed above can be implemented alone or in combination.

[0229] When firing is performed, the range of the firing temperature is not particularly limited. When the temperature is too high, the resistance of the substrate may be too high or the substrate may melt. Therefore, the fixing temperature is preferably 30°C to 700°C, more preferably 100°C to 600°C. In addition, the firing duration is not particularly limited, but the firing duration is preferably 10 minutes to 10 hours.

[0230] For microwave irradiation, microwaves can be applied from the side of the electron transport layer or the back side. The irradiation duration is not particularly limited, but the microwave irradiation is preferably performed within 1 hour.

[0231] After firing, electroless plating using a mixed solution of an aqueous titanium tetrachloride solution and an organic solvent, or electrochemical plating using an aqueous titanium tetrachloride solution, can be performed to increase the surface area of the semiconductor particles or increase the electron injection efficiency from the photosensitizing material to the semiconductor particles.

[0232] The film formed by laminating semiconductor particles with a diameter of several tens of nanometers by firing forms a porous state. The nanoporous structure has a very large surface area, and this surface area can be represented by a roughness factor.

[0233] The roughness factor is a value representing the actual area of the inner region of the pores relative to the area of the semiconductor particles applied to the substrate. Therefore, a larger roughness factor is more preferable. The roughness factor is related to the average thickness of the electron transport layer. In the present disclosure, the roughness factor is preferably 20 or more.

[0234] <<Photosensitizing Dye Electrode Layer>>

[0235] The solar cell includes a photosensitizing dye electrode layer to further improve the conversion efficiency. The photosensitizing dye electrode layer is a layer in which a photosensitizing dye (photosensitizing material) is adsorbed on the surface of an electron transport material that is the electron transport layer 4.

[0236] - Photosensitizing Dye (Photosensitizing Material)-

[0237] There is no limitation on the photosensitizing material 5 that acts as a photosensitizing dye as long as the photosensitizing material 5 is a compound that is photoexcited by the excitation light used.

[0238] Specific examples thereof include: the Japanese translation of the PCT international application publication number JP-T-07-500630, metal complex compounds disclosed in Japanese unexamined patent application publication numbers 10-233238, 2000-26487, 2000-323191, and 2001-59062; coumarin compounds disclosed in Japanese unexamined patent application publication numbers 10-93118, 2002-164089, and 2004-95450, and J. Phys. Chem. C, 7224, Vol. 111 (2007); polyene compounds disclosed in Japanese unexamined patent application publication numbers 2004-95450 and Chem. Commun., 4887 (2007); indoline compounds disclosed in Japanese unexamined patent application publication numbers 2003-264010, 2004-63274, 2004-115636, 2004-200068, and 2004-235052, J. Am. Chem. Soc., 12218, Vol. 126 (2004), Chem. Commun., 3036 (2003), and Angew. Chem. Int. Ed., 1923, Vol. 47 (2008); thiophene compounds disclosed in J. Am. Chem. Soc., 16701, Vol. 128 (2006) and J. Am. Chem. Soc., 14256, Vol. 128 (2006); cyanine dyes disclosed in Japanese unexamined patent application publication numbers 11-86916, 11-214730, 2000-106224, 2001-76773, and 2003-7359; merocyanine dyes disclosed in Japanese unexamined patent application publication numbers 11-214731, 11-238905, 2001-52766, 2001-76775, and 2003-7360; 9-aryl xanthene compounds disclosed in Japanese unexamined patent application publication numbers 10-92477, 11-273754, 11-273755, and 2003-31273; triarylmethane compounds disclosed in Japanese unexamined patent application publication numbers 10-93118 and 2003-31273; and Japanese unexamined patent application publication numbers 09-199744, 10-233238, 11-204821, 11-265738, J. Phys. Chem., 2342, Vol. 91 (1987), J. Phys. Chem. B, 6272, Vol. 97 (1993), Electroanal. Chem., 31, Vol. 537 (2002), Japanese unexamined patent application publication number 2006-032260, J. Porphyrins Phthalocyanines, 230, Vol. 3 (1999), Angew. Chem. Int. Ed., 373, the phthalocyanine compounds and coumarin compounds disclosed in Volume 46 (2007) and Langmuir, 5436, Volume 24 (2008). Among the examples listed above, metal complex compounds, coumarin compounds, polyene compounds, indoline compounds, and thiophene compounds are particularly preferably used.

[0239] As a method for adsorbing the photosensitizing material 5 onto the electron transport layer 4, a method of immersing a charge-collecting electrode including semiconductor particles in a photosensitizing material solution or dispersion, or a method of applying a solution or dispersion to the electron transport layer so that the semiconductor particles are adsorbed thereon can be adopted.

[0240] In the case of the former method, immersion, dip coating, roll coating, air knife coating, etc. can be adopted.

[0241] In the case of the latter method, wire bar coating, slide hopper coating, extrusion, curtain coating, spin coating, spray coating, etc. can be adopted.

[0242] In addition, the adsorption of semiconductor particles can be carried out using carbon dioxide, etc. in a supercritical fluid.

[0243] When adsorbing the photosensitizing material, a condensing agent can be used in combination.

[0244] The condensing agent can be an agent having a catalytic function to physically or chemically bond the photosensitizing material and the electron transport compound to the surface of the inorganic material, or an agent that acts stoichiometrically to favorably change the chemical equilibrium. In addition, a thiol or a hydroxy compound can be added as a condensation aid.

[0245] Examples of solvents for dissolving or dispersing the photosensitizing material include: water; alcohol solvents such as methanol, ethanol, and isopropyl alcohol; ketone solvents such as acetone, methyl ethyl ketone, and methyl isobutyl ketone; ester solvents such as ethyl formate, ethyl acetate, and n-butyl acetate; ether solvents such as diethyl ether, dimethoxyethane, tetrahydrofuran, dioxolane, and dioxane; amide solvents such as N,N-dimethylformamide, N,N-dimethylacetamide, and N-methyl-2-pyrrolidone; halogenated hydrocarbon solvents such as dichloromethane, chloroform, bromoform, methyl iodide, dichloroethane, trichloroethane, trichloroethylene, chlorobenzene, o-dichlorobenzene, fluorobenzene, bromobenzene, iodobenzene, and 1-chloronaphthalene; and hydrocarbon solvents such as n-pentane, n-hexane, n-octane, 1,5-hexadiene, cyclohexane, methylcyclohexane, cyclohexadiene, benzene, toluene, o-xylene, m-xylene, p-xylene, ethylbenzene, and isopropylbenzene. The examples listed above can be used alone or in combination.

[0246] In addition, there are photosensitizing materials that function more effectively when aggregation between compound molecules is suppressed according to the type of the photosensitizing material. Therefore, an aggregation dissociating agent can be used in combination.

[0247] The aggregation dissociating agent is preferably a steroid compound (e.g., cholic acid and chenodeoxycholic acid), a long-chain alkyl carboxylic acid, or a long-chain alkyl phosphonic acid. The aggregation dissociating agent can be appropriately selected according to the photosensitizing material used.

[0248] The amount of the aggregation dissociating agent is preferably 0.01 part by mass to 500 parts by mass, more preferably 0.1 part by mass to 100 parts by mass, relative to 1 part by mass of the photosensitizing material.

[0249] The adsorption temperature of the photosensitizing material or the combination of the photosensitizing material and the aggregation dissociating agent is preferably above -50°C but below 200°C. In addition, the adsorption can be carried out under static conditions or with stirring.

[0250] Examples of the stirring method include stirring using a stirrer, a ball mill, a paint conditioner, a sand mill, a grinder, and a disperser, as well as ultrasonic dispersion, but the method is not limited to the examples listed above. The time required for adsorption is preferably 5 seconds or more but 1000 hours or less, more preferably 10 seconds or more but 500 hours or less, and even more preferably 1 minute or more but 150 hours or less. In addition, the adsorption is preferably carried out in the dark.

[0251] <<Metal oxide layer>>

[0252] The metal oxide layer 6 in the solar cell and its production method are appropriately selected from the description of the metal oxide layer and its production method of the electronic device of the present disclosure.

[0253] <<Second electrode>>

[0254] The second electrode is provided after the metal oxide layer is formed.

[0255] In addition, an electrode the same as the first electrode can generally be used as the second electrode. The carrier does not have to be provided in a structure that sufficiently maintains strength and airtightness.

[0256] Specific examples of the material of the second electrode include: metals such as platinum, gold, silver, copper, and aluminum; carbon-based compounds such as graphite, fullerene, carbon nanotube, and graphene; conductive metal oxides such as ITO, FTO, and ATO; and conductive polymers such as polythiophene and polyaniline.

[0257] There is no specific limitation on the average thickness of the second electrode. In addition, the materials listed above can be used alone or in combination.

[0258] The second electrode can be appropriately formed on the hole transport layer by methods such as coating, lamination, evaporation, CVD, and bonding, depending on the material used or the type of the hole transport layer.

[0259] In order for the electronic device to act as a photoelectric conversion device (photoelectric conversion element), the first electrode or the second electrode or both are substantially transparent.

[0260] In the electronic device of the present disclosure, the side where the first electrode is provided is transparent, and preferably sunlight is applied from the side of the first electrode. In this case, preferably a material that reflects light is used on the side of the second electrode, and the material is preferably glass or plastic coated with a metal or a conductive oxide by evaporation, or a metal film.

[0261] In addition, it is also effective to provide an antireflection layer on the side where sunlight is applied.

[0262] The photoelectric conversion element of the present disclosure can be applied to a solar cell and a power supply including the solar cell. Application examples can be any device that utilizes the solar cell or the power supply using the solar cell. For example, the photoelectric conversion element can be used for the solar cell of a desktop electronic calculator or a watch. Examples of devices that utilize the properties of the photoelectric conversion element of the present disclosure include the power supply of a mobile phone, an electronic notepad, an electronic paper, etc. In addition, the photoelectric conversion element can be used as an auxiliary power supply to extend the continuous usage time of a rechargeable or dry battery-powered appliance. Further, the photoelectric conversion element can be used as a primary battery substitute combined with a secondary battery, serving as a self-sufficient power supply for a sensor.

[0263] <Organic electroluminescent element>

[0264] One embodiment of the electronic device of the present disclosure is an organic electroluminescent (EL) element.

[0265] The organic EL element includes a carrier, a charge transport layer including a charge transport material provided on or above the carrier, and a metal oxide layer provided on or above the charge transport layer. The organic EL element further includes a positive electrode (first electrode), a hole transport layer, a light-emitting layer, and a negative electrode (second electrode), and may further include other layers such as a barrier film.

[0266] Note that the layer including the positive electrode (first electrode), the hole transport layer, the light-emitting layer, the electron transport layer serving as the charge transport layer, and the negative electrode (second electrode) may be referred to as an "organic EL layer".

[0267] Examples of the electronic device being an organic EL element will be described below, but the electronic device is not limited to the organic EL element and can be applied to other embodiments of the electronic device.

[0268] Figure 8An organic EL element 10C is exemplified as an embodiment of the electronic device of the present disclosure. An organic EL element having a metal oxide layer on the outermost surface layer of the organic EL layer is provided. The organic EL element 10C includes a substrate 20 serving as a carrier, an organic EL layer 30, and a metal oxide layer 40.

[0269] Note that the present disclosure is not limited to the embodiments described below. The embodiments described below can be changed, such as additional embodiments can be adopted, or additions, corrections, or omissions can be made to the following embodiments within the scope achievable by those skilled in the art, and any of the above embodiments are included in the scope of the present disclosure as long as the functions and effects of the present disclosure are presented.

[0270] <<Carrier (substrate)>>

[0271] The substrate 20 serving as a carrier is an insulating substrate. The substrate 20 can be a plastic or film substrate.

[0272] A barrier film can be provided on the main surface 20a of the substrate 20.

[0273] The barrier film is, for example, a film formed of silicon, oxygen, and carbon, or a film formed of silicon dioxide, oxygen, carbon, and nitrogen. Examples of the material of the barrier film include silicon oxide, silicon nitride, and silicon oxynitride. The average thickness of the barrier film is preferably 100 nm or more but 10 µm or less.

[0274] <<Organic EL layer>>

[0275] The organic EL layer 30 includes a light-emitting layer and is a functional part that promotes the light emission of the light-emitting layer (such as carrier migration or carrier recombination) according to the voltage applied between the positive electrode and the negative electrode. For example, the organic EL layer is formed by laminating a positive electrode, a hole transport layer, a light-emitting layer, an electron transport layer, and a negative electrode in this order from the side of the support substrate 20.

[0276] The organic EL layer 30 is not particularly limited and can be appropriately selected from known organic EL elements in the art according to the intended purpose.

[0277] A transparent electrode is laminated as the negative electrode.

[0278] The transparent electrode is formed by using a conductive metal oxide such as SnO2, In2O3, ITO, IZO, and ZnO:Al. When the transparent electrode is used as the negative electrode, an electron injection layer is desirably provided as the uppermost layer of the organic EL layer to improve the electron injection efficiency. The transparent electrode has a transmittance of preferably 50% or more, more preferably 85% or more, for light with a wavelength of 400 nm to 800 nm. The average thickness of the transparent electrode is preferably 50 nm or more, more preferably 50 nm to 1 µm, and even more preferably 100 nm to 300 nm.

[0279] <<Metal oxide layer>>

[0280] The metal oxide layer 40 of the organic EL element and its production method are appropriately selected from the description of the metal oxide layer of the electronic device of the present disclosure and its production method.

[0281] The metal oxide layer 40 is provided on the negative electrode to embed the organic EL layer 30 therein. The metal oxide layer 40 is provided on the organic EL layer 30, on the side opposite to the side where the substrate 20 is provided. The metal oxide layer 40 has a gas barrier function, specifically a moisture barrier function.

[0282] Examples

[0283] The present disclosure will be described in more detail by way of examples and comparative examples. The present disclosure should not be construed as being limited to these examples. In the following description, "parts" means "parts by mass".

[0284] - Preparation of copper-aluminum oxide -

[0285] Copper-aluminum oxide was prepared in the following manner. Cuprous oxide and aluminum oxide were weighed in equimolar amounts. The collected cuprous oxide and aluminum oxide were transferred to a mayonnaise bottle, and the mixture therein was stirred by a tube mixer (type T2C, available from Willy A. Bachofen AG Maschinenfabrik) to obtain a powder mixture. The obtained powder mixture was heated at 1,100 °C for 40 hours, and the resulting product was passed through a sieve having a pore diameter of 100 microns.

[0286] <Powder mixture materials>

[0287] Cuprous oxide (NC-803, available from NC TECH Co., Ltd.): 12 kg

[0288] Aluminum oxide (AA-03, available from SUMITOMO CHEMICAL COMPANY, LIMITED): 8.58 kg

[0289] The obtained copper-aluminum oxide was pulverized by DRYSTAR SDA1 (available from Ashizawa Finetech Ltd.) to obtain copper-aluminum oxide powder having cumulative particle size numbers of 0.7 ± 0.1 μm, 5.0 ± 0.5 μm, and 26 ± 3 μm for 10% (D10), 50% (D50), and 90% (D90), respectively. The powder of copper-aluminum oxide was vacuum-dried at 100 °C to adjust the moisture content of the aluminum copper oxide to 0.2 mass% or less.

[0290] The particle size of the copper-aluminum oxide is a value measured by MICROTRAC MT3300 (MicrotracBEL Corp.) using an aqueous solution of 0.2% sodium hexametaphosphate as a dispersion medium with a measurement duration of 10 seconds.

[0291] Regarding the measurement of the moisture content of the copper-aluminum oxide, a Karl Fischer moisture meter (CA-200, available from Mitsubishi Chemical Analytech Co., Ltd.) is used.

[0292] The elemental composition ratio of the copper-aluminum oxide is determined by an X-ray fluorescence spectrometer (ZSX PrimusIV, available from Rigaku Corporation), and the crystal structure is measured by an X-ray diffractometer (X’Pert PRO, available from Spectris Co., Ltd.).

[0293] <Example 1>

[0294] -Production Examples of Electrophotographic Photoreceptors-

[0295] Twenty electrophotographic photoreceptors of Example 1 were each produced in the following manner. Each electrophotographic photoreceptor of Example 1 includes an intermediate layer, a charge generation layer, a charge transport layer, a silicone hard coat, and a metal oxide layer provided on a conductive support in this order.

[0296] --Forming the Intermediate Layer--

[0297] The following intermediate layer coating solution was applied to an aluminum conductive support (outer diameter: 100 mm, thickness: 1.5 mm) by dip coating to form the intermediate layer. After drying at 150 °C for 30 minutes, the average thickness of the intermediate layer was 5 μm.

[0298] <Intermediate Layer Coating Solution>

[0299] Zinc oxide particles (MZ-300, available from TAYCA CORPORATION): 350 parts

[0300] 3,5-Di-tert-butylsalicylic acid (available from Tokyo Chemical Industry Co., Ltd.): 1.5 parts

[0301] Blocked isocyanate (Sumidur (registered trademark) 3175, solid content: 75 mass%, available from Sumika Bayer Urethane Co., Ltd.): 60 parts

[0302] A solution obtained by dissolving butyral resin (20% by mass) in 2-butanone (BM-1, available from SEKISUICHEMICAL CO., LTD.): 225 parts

[0303] 2-butanone: 365 parts

[0304] --Forming a charge generation layer--

[0305] The following charge generation layer coating solution was applied to the obtained intermediate layer by dip coating to form a charge generation layer. The average thickness of the charge generation layer is 0.2 micrometers.

[0306] <Charge generation layer coating solution>

[0307] Y-type titanium oxyphthalocyanine: 6 parts

[0308] Butyral resin (S-LEC BX-1, available from SEKISUI CHEMICAL CO., LTD.): 4 parts

[0309] 2-butanone (available from KANTO CHEMICAL CO., INC.): 200 parts

[0310] --Forming a charge transport layer--

[0311] The following charge transport layer coating solution was applied to the obtained charge generation layer by dip coating to form a charge transport layer.

[0312] After drying at 135 °C for 20 minutes, the average thickness of the charge transport layer is 22 micrometers.

[0313] <Charge transport layer coating solution>

[0314] Bisphenol Z polycarbonate (PANLITE TS-2050, available from TEIJIN LIMITED): 10 parts

[0315] Low molecular weight charge transport material having the following structural formula: 10 parts

[0316] [Chemistry 1]

[0317]

[0318] Tetrahydrofuran: 80 parts

[0319] -Forming a silicone hard coat-

[0320] The following silicone hard coat coating solution was applied to the obtained charge transport layer by loop coating to form a silicone hard coat.

[0321] After drying at 135 °C for 20 minutes, the average thickness of the silicone hard coat is 0.5 micrometers.

[0322] (Silicone hard coat coating liquid)

[0323] Silicone hard coat liquid (NSC-5506, available from NIPPON FINE CHEMICAL CO., LTD.): 80 parts

[0324] Tetrahydrofuran: 20 parts

[0325] --Forming a metal oxide layer--

[0326] As the film-forming chamber, a chamber obtained by modifying a commercially available vapor deposition apparatus was used.

[0327] A commercially available stirrer (T.K.AGI HOMO MIXER 2M-03, available from PRIMIX Corporation) was used for the aerosol generator. Note that as the aerosol generator, an ultrasonic cleaner (SUS-103, available from Shimadzu Corporation) provided with a commercially available pressure supply bottle (RBN-S, available from Kato Stainless Kagaku Co.) having a volume of 1 L can be used.

[0328] A tube with an inner diameter of 4 mm was led from the aerosol generator to the film-forming chamber, and an injection nozzle (YB1 / 8MSSP37, available from Spraying Systems Co.) was attached to the edge of the tube. The photoreceptor was set at a position 50 mm away from the injection nozzle. As the photoreceptor holder, a mechanism that can rotate the photosensitive drum was set. As the injection nozzle, an injection nozzle that can move laterally was used. The aerosol generator and the nitrogen gas cylinder were connected by a pipe with an inner diameter of 4 mm.

[0329] Using the above device, a target metal oxide layer with an average thickness of 1.5 micrometers was produced in the following manner.

[0330] A powder mixture with a mass ratio of 99.5%:0.5% including copper-aluminum oxide and silica particles (Reolosil ZD-30S, available from Tokuyama Corporation) obtained in the above manner was loaded into the aerosol generator. The silica particles had been surface-treated with dimethyldichlorosilane and hexamethyldisilazane and had a BET surface area of 190 ± 25 m 2 / g and a carbon content of 2.9 mass%.

[0331] Next, a vacuum is drawn from the film-forming chamber to the aerosol generator using an exhaust pump. Then, nitrogen gas is fed from a gas cylinder into the aerosol generator, and stirring is started to generate an aerosol in which particles are dispersed in the nitrogen gas. The generated aerosol is sprayed from a spray nozzle toward the photoreceptor through a tube. The flow rate of the nitrogen gas is from 13 L / min to 20 L / min. In addition, the film-forming duration is 20 minutes, and the degree of vacuum inside the film-forming chamber during the formation of the metal oxide layer is from about 50 Pa to about 150 Pa.

[0332] The amount of silica particles included on the surface of the photoreceptor is determined by an X-ray fluorescence spectrometer (ZSX Primus IV, available from Rigaku Corporation). The amount of silica particles included in the photoreceptor is the same as the charged amount.

[0333] <Example 2>

[0334] Twenty electrophotographic photoreceptors are produced in the same manner as in Example 1, except that the amount of silica particles in the powder mixture including copper aluminate oxide and silica particles used for forming the metal oxide layer is changed to 1.0 mass%.

[0335] <Example 3>

[0336] Twenty electrophotographic photoreceptors are produced in the same manner as in Example 1, except that the amount of silica particles in the powder mixture including copper aluminate oxide and silica particles used for forming the metal oxide layer is changed to 1.5 mass%.

[0337] <Example 4>

[0338] Twenty electrophotographic photoreceptors are produced in the same manner as in Example 2, except that the silica particles in the powder mixture including copper aluminate oxide and silica particles used for forming the metal oxide layer are changed to silica particles that have been surface-treated with dimethyldichlorosilane, have a BET specific surface area of 200 ± 25 m 2 / g and have a carbon content of 2.8 mass% (HDK H-2000, available from Wacker Asahikasei Silicone Co., Ltd.).

[0339] <Example 5>

[0340] Twenty electrophotographic photoreceptors are produced in the same manner as in Example 2, except that the silica particles in the powder mixture including copper aluminate oxide and silica particles used for forming the metal oxide layer are changed to silica particles that have been surface-treated with dimethyldichlorosilane, have a BET specific surface area of 250 ± 25 m 2Aerosil R976 (available from NIPPON AEROSIL CO., LTD.) having a BET specific surface area of 140 ± 25 m² / g and a carbon content of 1.8 mass%.

[0341] <Example 6>

[0342] Twenty electrophotographic photoreceptors were produced in the same manner as in Example 2, except that the silica particles in the powder mixture including copper-aluminum oxide and silica particles used for forming the metal oxide layer were changed to Aerosil RA200HS (available from NIPPON AEROSIL CO., LTD.) having a BET specific surface area of 140 ± 25 m² / g and a carbon content of 1.8 mass%, which had been surface-treated with trimethylsilyl and amino groups. 2 Aerosil RA200HS (available from NIPPON AEROSIL CO., LTD.) having a BET specific surface area of 140 ± 25 m² / g and a carbon content of 1.8 mass%.

[0343] <Comparative Example 1>

[0344] Twenty electrophotographic photoreceptors were produced in the same manner as in Example 1, except that no silica particles were added to the powder mixture including copper-aluminum oxide and silica particles used for forming the metal oxide layer.

[0345] <Comparative Example 2>

[0346] Twenty electrophotographic photoreceptors were produced in the same manner as in Example 1, except that the amount of silica particles in the powder mixture including copper-aluminum oxide and silica particles used for forming the metal oxide layer was changed to 0.3 mass%.

[0347] <Comparative Example 3>

[0348] Twenty electrophotographic photoreceptors were produced in the same manner as in Example 1, except that the amount of silica particles in the powder mixture including copper-aluminum oxide and silica particles used for forming the metal oxide layer was changed to 2.0 mass%.

[0349] <Example 7>

[0350] Twenty electrophotographic photoreceptors were produced in the same manner as in Example 1, except that the metal oxide layer was formed using a powder mixture including copper-aluminum oxide and alumina particles (AKP-50, available from SUMITOMO CHEMICAL COMPANY, LIMITED) having a volume average particle diameter of 0.20 µm and a BET specific surface area of 10.3 m² / g at a mass ratio of 99.5%:0.5%. 2 A BET specific surface area of 10.3 m² / g and alumina particles (AKP-50, available from SUMITOMO CHEMICAL COMPANY, LIMITED) having a volume average particle diameter of 0.20 µm.

[0351] <Example 8>

[0352] Twenty electrophotographic photoreceptors were produced in the same manner as in Example 7, except that the amount of metal oxide particles in the powder mixture including copper-aluminum oxide and metal oxide particles used for forming the metal oxide layer was changed to 1.0 mass%.

[0353] <Example 9>

[0354] Twenty electrophotographic photoreceptors were produced in the same manner as in Example 7, except that the amount of metal oxide particles in the powder mixture including copper-aluminum oxide and metal oxide particles used for forming the metal oxide layer was changed to 1.5 mass%.

[0355] <Example 10>

[0356] Twenty electrophotographic photoreceptors were produced in the same manner as in Example 8, except that the metal oxide particles in the powder mixture including copper-aluminum oxide and metal oxide particles used for forming the metal oxide layer were changed to alumina (AKP-20, available from SUMITOMO CHEMICAL COMPANY, LIMITED) having a volume average particle diameter of 0.46 µm and a BET specific surface area of 4.3 m 2 / g.

[0357] <Example 11>

[0358] Twenty electrophotographic photoreceptors were produced in the same manner as in Example 8, except that the metal oxide particles in the powder mixture including copper-aluminum oxide and metal oxide particles used for forming the metal oxide layer were changed to TM-DAR (available from TAIMEI CHEMICALS CO., LTD.) having a volume average particle diameter of 0.10 µm and a BET specific surface area of 14.5 m 2 / g.

[0359] <Example 12>

[0360] Twenty electrophotographic photoreceptors were produced in the same manner as in Example 8, except that the metal oxide particles in the powder mixture including copper-aluminum oxide and metal oxide particles used for forming the metal oxide layer were changed to SF-10 (available from SAKAI CHEMICAL INDUSTRY CO., LTD.) having a particle diameter of 0.28 µm and a BET specific surface area of 11.0 m 2 / g.

[0361] <Comparative Example 4>

[0362] Twenty electrophotographic photoreceptors were produced in the same manner as in Example 7, except that the amount of metal oxide particles in the powder mixture including copper-aluminum oxide and metal oxide particles used for forming the metal oxide layer was changed to 0.3% by mass.

[0363] <Comparative Example 5>

[0364] Twenty electrophotographic photoreceptors were produced in the same manner as in Example 7, except that the amount of metal oxide particles in the powder mixture including copper-aluminum oxide and metal oxide particles used for forming the metal oxide layer was changed to 2.0% by mass.

[0365] <Evaluate the electrophotographic photoreceptor>

[0366] In each of the electrophotographic photoreceptors of Examples 1 to 12 and Comparative Examples 1 to 5 produced as described above, the thickness of a cylindrical photosensitive drum having a length of 380 mm and an outer diameter of 100 mm was measured at five points taken at 50 mm intervals in the longitudinal direction from a position 100 mm from the drum edge to a position 300 mm from the drum edge. The thickness of 20 photosensitive drums was measured to obtain thickness data for a total of 100 points. The thickness was measured by the method using light interference as described in Japanese Patent No. 5521607. In addition to determining the thickness from the average value of the obtained data, the standard deviation was also determined.

[0367] Based on the obtained average thickness and standard deviation, the process capability index Cpk was calculated according to the following equations (1) to (3). The results are shown in Table 1. The process capability index is a value that evaluates the degree of deviation of the arithmetic mean X of the thickness from the standard median. A larger Cpk means a higher ability to produce photosensitive drums with stable production quality.

[0368] [Mathematics 4]

[0369] Cpk = Cp(1 - K) (1)

[0370] [Mathematics 5]

[0371]

[0372] [Mathematics 6]

[0373]

[0374] In the above equations, USL is the standard upper limit value, LSL is the standard lower limit value, X is the arithmetic mean of the thickness, and σ is the standard deviation. In addition, Cp is the comparison of 6σ representing the variation of the film-forming process with the standard width.

[0375] Since it is impossible to measure a large number of photoreceptors when judging the influence of process capabilities on the products launched on the market, evaluation can be carried out by obtaining thickness measurement values of a total of 100 points under the condition of shortening the measurement interval.

[0376]

[0377] From the results in Table 1, it was found that the thickness unevenness of the metal oxide layer in each electrophotographic photoreceptor obtained in Examples 1 to 12 was small.

[0378] It was found that when the amount of silica particles in the powder mixture including cuproaluminum oxide and silica particles for the metal oxide layer was changed from 0.5% by mass in Example 1 to 1.5% by mass in Example 3, a high Cpk was obtained.

[0379] In addition, it was found that when the amount of metal oxide particles in the powder mixture including cuproaluminum oxide and metal oxide particles for the metal oxide layer was changed from 0.5% by mass in Example 7 to 1.5% by mass in Example 9, a high Cpk was obtained.

[0380] For example, the embodiments of the present disclosure are as follows:

[0381] <1> An electronic device, comprising:

[0382] A carrier;

[0383] A charge transport layer including a charge transport material or a sensitizing dye electrode layer including a sensitizing dye, wherein the charge transport layer or the sensitizing dye electrode layer is disposed on or above the carrier; and

[0384] A metal oxide layer, the metal oxide layer being disposed on or above the charge transport layer or the sensitizing dye electrode layer,

[0385] wherein the metal oxide layer includes a p-type semiconductor metal oxide and silica or metal oxide particles, and

[0386] wherein the amount of silica or metal oxide particles included in the metal oxide layer is 0.5% by mass or more but 1.5% by mass or less with respect to the metal oxide layer.

[0387] <2> The electronic device according to <1>,

[0388] wherein the average thickness of the metal oxide layer is 1.2 micrometers or more but 1.8 micrometers or less, and the standard deviation of the thickness of the metal oxide is 0.07 micrometers or less.

[0389] <3> The electronic device according to <1> or <2>,

[0390] wherein the p-type semiconductor metal oxide is cuprospinel oxide.

[0391] <4>The electronic device according to <3>,

[0392] wherein the cupric iron oxide is cupric aluminum oxide.

[0393] <5>A method for producing an electronic device, the method comprising:

[0394] spraying a p-type semiconductor metal oxide and silicon dioxide or metal oxide particles to form a metal oxide layer,

[0395] wherein the electronic device comprises:

[0396] a carrier;

[0397] a charge transport layer comprising a charge transport material or a sensitizing dye electrode layer comprising a sensitizing dye, wherein the charge transport layer or the sensitizing dye electrode layer is disposed on or above the carrier; and

[0398] a metal oxide layer, the metal oxide layer being disposed on or above the charge transport layer or the sensitizing dye electrode layer.

[0399] <6>The method according to <5>,

[0400] wherein the spraying is aerosol deposition.

[0401] <7>An imaging method, comprising:

[0402] forming an image by using an electrochromic device according to any one of <1> to <4>.

[0403] <8>An imaging device, comprising:

[0404] an electrochromic device according to any one of <1> to <4>.

[0405] The electronic device according to any one of <1> to <4>, the method for producing an electronic device according to <5> or <6>, the imaging method according to <7>, and the imaging device according to <8> can solve the various problems existing in the art and can achieve the object of the present disclosure.

[0406] List of reference numerals

[0407] 1A: Charge clearing device

[0408] 1B: Pre-cleaning exposure device

[0409] 1C: Driving unit

[0410] 1D: First transfer device

[0411] 1E: Second transfer device

[0412] 1F: Intermediate transfer member

[0413] 1G: Transfer belt

[0414] 3: Lubricant coating device

[0415] 3A: Lubricant

[0416] 3B: Coating brush

[0417] 3C: Coating blade

[0418] 3D: Pressure spring

[0419] 10A: Electrostatic latent image carrier (electrophotographic photoreceptor)

[0420] 10B: Solar cell

[0421] 10C: Organic electroluminescent element

[0422] 11, 11Bk, 11C, 11M, 11Y: Electrophotographic photoreceptor

[0423] 12, 12Y, 12M, 12C, 12Bk: Charging device

[0424] 13, 13Y, 13M, 13C, 13Bk: Exposure device

[0425] 14, 14Bk, 14C, 14M, 14Y: Developing device

[0426] 15: Toner

[0427] 16, 16Y, 16M, 16C, 16Bk: Transfer device

[0428] 17, 17Y, 17M, 17C, 17Bk: Cleaning device

[0429] 18: Print medium

[0430] 19: Fusing device

Claims

1. An electronic device, comprising: A carrier; A charge transport layer including a charge transport material or a sensitizing dye electrode layer including a sensitizing dye, wherein the charge transport layer or the sensitizing dye electrode layer is disposed on or above the carrier; And A metal oxide layer, the metal oxide layer being disposed on or above the charge transport layer or the sensitizing dye electrode layer, Wherein the metal oxide layer includes p-type semiconductor metal oxide particles, and wherein the metal oxide layer further includes silica or metal oxide particles, Wherein the amount of the silica or metal oxide particles included in the metal oxide layer is 0.5% by mass or more but 1.5% by mass or less relative to the metal oxide layer, Wherein the p-type semiconductor metal oxide is copper aluminum oxide, and Wherein the metal oxide in the metal oxide particles is alumina or zinc oxide.

2. The electronic device according to claim 1, wherein an average thickness of the metal oxide layer is 1.2 micrometers or more but 1.8 micrometers or less, and a standard deviation of the thickness of the metal oxide layer is 0.07 micrometers or less.

3. The electronic device according to claim 1 or 2, wherein the copper aluminum oxide is derived from cuprite oxide.

4. A method for producing an electronic device, the method comprising: Spraying p-type semiconductor metal oxide and silica particles, or p-type semiconductor metal oxide and metal oxide particles to form a metal oxide layer, Wherein the electronic device includes: A carrier; A charge transport layer including a charge transport material or a sensitizing dye electrode layer including a sensitizing dye, wherein the charge transport layer or the sensitizing dye electrode layer is disposed on or above the carrier; and The metal oxide layer, the metal oxide layer being disposed on or above the charge transport layer or the sensitizing dye electrode layer, Wherein the p-type semiconductor metal oxide is copper aluminum oxide, Wherein the metal oxide in the metal oxide particles is alumina or zinc oxide, and Wherein the amount of the silica particles or metal oxide particles included in the metal oxide layer is 0.5% by mass or more but 1.5% by mass or less relative to the metal oxide layer.

5. The method according to claim 4, wherein the spraying is aerosol deposition.

6. An imaging method, comprising: Forming an image using the electronic device according to any one of claims 1 to 3.

7. An imaging device, comprising: The electronic device according to any one of claims 1 to 3.

Images