TW201843210A - Insulation film laminated metal plate and metal substrate - Google Patents

Abstract

The insulation film laminated metal plate of the present invention has a metal plate, and an insulation film laminated on at least one side of the metal plate, wherein: the insulation film contains a heat-curing resin; the heat-curing resin contains a polyester resin constituted by dicarboxylic acid-derived units containing at least 90 mol% in total of terephthalic acid-derived units and isophthalic acid-derived units, and polyol-derived units containing at least 90 mol% of polyol-derived units having a carbon number of 2 to 5; the mole percentage of the terephthalic acid-derived units in the dicarboxylic acid-derived units is 40-70% and the mole percentage of the isophthalic acid-derived units in the dicarboxylic acid-derived units is 30-60%; and the adjusted average carbon number of the polyol-derived units calculated using formula (1) is 3.4 or less.

Description

Insulation film laminated metal plate and metal substrate

The invention relates to an insulating film laminated metal plate and a metal substrate. More specifically, it relates to an insulating film laminated metal plate and a metal substrate used in a top emission organic EL element or a bottom plate type thin film solar cell.

Organic semiconductors are flexible, can be thinned, and even save power. Therefore, they can be expected to be applied to organic electronic devices such as top-emission organic EL (electroluminescence) elements or backplane-type thin-film solar cells. The organic EL element includes a light-emitting layer containing an organic semiconductor, and further includes, for example, an anode made of ITO (indium tin oxide) having both transparency and conductivity, and a cathode made of, for example, IZO (indium zinc oxide). On the other hand, the solar cell includes a photoelectric conversion layer made of an organic semiconductor, and further includes, for example, a back electrode and a front electrode made of ITO, respectively.

When glass is used as a substrate of an organic electronic device, there are problems of easy breakage and lack of workability. On the other hand, when plastic is used, since it has moisture permeability, there is a problem that a gas shielding layer must be provided. Therefore, as a substrate of an organic electronic device, the use of an insulating film laminated metal plate in which an insulating film is laminated on a metal plate has been reviewed.

For example, Patent Document 1 discloses an insulating film-laminated metal plate having a surface roughness of 30 nm or less and a film thickness of 10 to 40 μm, and a film containing polyester as a thermosetting resin laminated on the surface of the metal plate only in one layer. In addition, Patent Document 2 discloses that a thermosetting resin coating film layer is provided on one or both sides of a metal plate. The surface roughness of the resin coating film layer is 20 nm or less and the total film thickness is 1 to 30 μm. The main resin is an insulating film laminated metal plate of polyester resin.

The organic EL element can be obtained by sequentially laminating an anode, a light-emitting layer, and a cathode on the insulating film of the insulating film-laminated metal plate. By disposing the organic EL element in a light-emitting circuit and allowing a current to flow therethrough, the light-emitting layer emits light.

On the other hand, the solar cell can be obtained by sequentially laminating a back electrode, a photoelectric conversion layer, and a surface electrode on the insulating film of the insulating film-laminated metal plate. This solar cell is installed in a power generation circuit and is irradiated with sunlight. As a result of the movement of charge due to the photoelectric conversion layer, the solar cell generates electricity. [Prior Art Literature] [Patent Literature]

[Patent Document 1] Japanese Patent Application Publication No. 2014-208479 208 [Patent Document 2] Japanese Patent Application Publication No. 2016-193580

When the above-mentioned organic EL element is produced by using the insulating film laminated metal plates disclosed in Patent Documents 1 and 2 to emit light, the organic EL element has a width of 5 to 5 as shown in FIG. 1. A light and dark stripe pattern with a length of 10 μm and a length of 20 to 50 μm emits light. The organic EL element that emits light in such a striped pattern has color spots or insufficient luminous intensity compared with an organic EL element that emits light uniformly on the surface of the light emitting layer, and cannot meet the performance required as an organic EL element. As will be described later, the light emission having the above-mentioned stripe pattern is caused by wrinkles on the surface of the conductive film layer when a conductive film layer is formed by sputtering on the insulating film of the insulating film laminated metal plate.

On the other hand, when the above-mentioned solar cell is produced by using the insulating film laminated metal plates disclosed in Patent Literature 1 and Patent Literature 2 to generate electricity, the amount of electricity generated may decrease due to wrinkles on the surface of the conductive thin film layer. .

Therefore, a metal substrate without wrinkles on the surface of the conductive thin film layer and an insulating film laminated metal plate in which the wrinkles do not occur when the conductive thin film layer is formed by sputtering are being required.

The present invention has been made in view of the above circumstances, and an object thereof is to provide an insulating film laminated metal plate capable of suppressing occurrence of wrinkles when a conductive thin film layer is formed by sputtering, and a metal substrate in which occurrence of wrinkles on the surface of the conductive thin film layer is suppressed.

One aspect of the present invention is an insulating film laminated metal plate comprising a metal plate and an insulating film laminated on at least one side of the metal plate, the insulating film contains a thermosetting resin, and the thermosetting resin contains a polymer An ester resin consisting of a dicarboxylic acid-derived unit and a polyhydric alcohol-derived unit. The dicarboxylic acid-derived unit contains terephthalic acid-derived units and isophthalic acid-derived units in total at 90 mol. % Or more, the unit derived from the polyhydric alcohol contains 90% or more of the unit derived from the polyhydric alcohol having 2 to 5 carbon atoms, and the mole percentage of the unit derived from the terephthalic acid in the unit derived from the dicarboxylic acid is 40 to 70%, the molar percentage of the isophthalic acid-derived unit to the dicarboxylic acid-derived unit is 30 to 60%, and the polyol-derived unit is calculated from the following formula (1) The adjusted average carbon number is 3.4 or less, and it is used to form a conductive thin film layer on the insulating film.

[Mathematical formula 1]

Another aspect of the present invention is a metal substrate in which a conductive thin film layer is laminated on an insulating film included in the insulating film laminated metal plate.

The objects, features, forms, and advantages of the present invention can be more clearly understood through the following detailed description and drawings.

First, a case where a top emission type organic EL element OLED element (organic light emitting diode element) is manufactured is used as an example to explain the outline of the process of completing the present invention.

When an OLED element is produced using an insulating film laminated metal plate in which an insulating film is laminated on a metal plate, the insulating film laminated metal plate is first washed, and an ITO layer is formed on the insulating film by sputtering as a positive electrode. Thereby, a metal substrate having an ITO layer as a conductive thin film layer can be obtained. Next, on the ITO layer, the raw material composition of each layer is vapor-deposited, coated, and heated to be laminated in the order of a positive hole injection rhenium transport layer, a light-emitting layer, and an electron transport layer. Next, an IZO layer as a cathode was formed on the electron transport layer by sputtering. Then, a transparent sealing glass was laminated on the IZO layer. Thereby, an OLED element can be obtained. Since the organic semiconductors constituting the above-mentioned positive hole-injection ytterbium transport layer, light-emitting layer, and electron transport layer have low charge mobility, the thickness of these layers is set to a value of several tens to hundreds of nm, respectively. In addition, the thickness of the IZO layer constituting the cathode is also set to a value from several tens of nm to several hundreds of nm.

When the OLED element obtained in such a manner is caused to emit light, color spots or insufficient luminous illumination may occur. The present inventors observed the light emission state of the surface of the OLED element in which a color spot occurs with an optical microscope. The observation results are shown in FIG. 1. FIG. 1 is a schematic substitute photograph of an optical microscope image showing the light-emitting state of the surface of the OLED element where the color spot occurs. As a result, it was found that the color spot was caused by the light emission of the OLED element showing a light and dark stripe pattern with a width of 5 to 10 μm and a length of 20 to 50 μm. In addition, it was found that an OLED device exhibiting such a striped pattern and emits light. Compared with an OLED device that uniformly emits light on the entire surface, not only the light emission illuminance is lower, but also the short-life of the strong light-emitting portion in the light-emitting layer may easily lead to the life of the OLED device. Relatively short.

The present inventors have studied and examined the reason why the OLED element where the color spots occur exhibits the above-mentioned light and dark streaks. Moreover, the reason was investigated. When the ITO layer was formed, wrinkles with a height difference of tens to hundreds of nm occurred on the surface of the ITO layer, and the wrinkles were injected into the plutonium transport layer through the positive holes of the thin layer to emit light. Layer, electron transport layer, and IZO layer are reflected on the element surface.

It is estimated that the above-mentioned wrinkles on the surface of the ITO layer are affected by the heat of sputtering, and the temperature of the insulating film under the ITO layer rises to about 200-250 ° C based on the calculated value based on energy calculation, and the insulating film softens and occurs.

Therefore, various strategies for forming the ITO layer, even if sputtering was used, did not soften the insulating film at a temperature of about 200 to 250 ° C. Then, it was found that by including the thermosetting resin contained in the insulating film with a polyester resin having a specific composition, softening due to an increase in the temperature of the insulating film caused by sputtering was suppressed, and the ITO layer was used as a conductive thin film layer. The occurrence of wrinkles is suppressed, and the present invention has been completed.

In addition, in this specification, a wrinkle refers to a convex group (multiple ridges) formed on the surface layer of an object and having a length of 20 to 50 μm, a width of 5 to 10 μm, and a height (the difference between the height of mountains and valleys) of 100 nm or more. The unevenness seen when the surface of the object to be observed is observed under a microscope. An example of wrinkles is shown in FIG. 3. FIG. 3 is a schematic substitute photograph showing an atomic force microscope image of the surface of the ITO layer in the metal substrate of Example No. 2. FIG.

In addition, in this specification, the mole ratio of the terephthalic acid-derived unit to the dicarboxylic acid-derived unit refers to the molar fraction of the terephthalic acid-derived unit to the dicarboxylic acid-derived unit. The percentage of 100 moles of the unit.

[Insulating Film Laminated Metal Plate] Next, an insulating film laminated metal plate according to an aspect of the present invention will be described.

The insulating film laminated metal plate of the present invention includes a metal plate and an insulating film laminated on at least one side of the metal plate. The insulating film contains a thermosetting resin. The thermosetting resin contains a polyester resin which is composed of a dicarboxylic acid-derived unit and a polyhydric alcohol-derived unit, and the dicarboxylic acid-derived unit includes a terephthalic acid-derived unit and isophthalene-derived unit. The unit of formic acid is 90 mol% or more in total, and the unit derived from the polyol contains 90 mol% or more of units derived from a polyol having 2 to 5 carbon atoms. The molar ratio of the terephthalic acid-derived unit to the dicarboxylic acid-derived unit is 40 to 70%. The molar percentage of the isophthalic acid-derived unit to the dicarboxylic acid-derived unit is 30 to 60%. The adjusted average carbon number of the unit derived from the polyol calculated from the above formula (1) is 3.4 or less. The insulating film laminated metal plate of the present invention is used for forming a conductive thin film layer on the insulating film.

The reason for specifying in this manner is described below.

1. Metal plate The metal plate used for the insulating film laminated metal plate of the present invention is a cold-rolled steel plate, a molten pure galvanized steel plate, an alloyed molten Zn-Fe plated steel plate, and an alloyed molten Zn-5% Al plated steel plate. , 55% Al-Zn alloy plated steel plate, electroplated pure zinc steel plate, electroplated Zn-Ni steel plate, aluminum plate, or titanium plate. As the metal plate, an untreated material (so-called bare plate) whose surface is not chemically treated can be used. However, from the viewpoint of improving the adhesion caused by the chemical bonding between the metal plate and the insulating film, the metal plate is made of a chromate material having a chromate treatment on its surface or a non-chromate surface. Treated non-chromate materials are preferred. From the viewpoint of environmental protection, it is preferable to use a non-chromate material for the metal plate. The thickness of the metal plate is not particularly limited. Depending on the application of the insulating film laminated metal plate, it is about 0.3 to 2.0 mm, for example.

2. Insulating film In the present invention, the insulating film has electrical insulation. More specifically, when the organic electronic device manufactured by using the insulating film laminated metal plate of the present invention is used, the insulating film has electrical insulation properties such that current does not leak from the layer directly above the metal plate to the metal plate.

The insulating film can be laminated on one or both sides of the metal plate according to the application of the insulating film laminated metal plate. The insulating film may be laminated directly on the metal plate, or may be laminated on the metal plate through other layers. By laminating the insulating film on the metal plate, electrical insulation between the metal plate and a layer (for example, a conductive thin film layer) laminated on the upper side of the insulating film can be ensured.

The thickness of the insulating film is not particularly limited, and from the viewpoint of securely ensuring the electrical insulation of the insulating film, the thickness of the insulating film is preferably 10 μm or more. On the other hand, when the thickness of the insulating film exceeds 50 μm, the electrical insulating properties of the insulating film tend to saturate. Therefore, the thickness of the insulating film is preferably 50 μm or less.

The insulating film mainly contains a thermosetting resin.

In addition, in order to adjust the light emission color of the organic electronic device produced by using the insulating film laminated metal plate in accordance with the application of the insulating film laminated metal plate, the insulating film may contain a white pigment such as titanium oxide as described later. Pigments of various colors, such as black pigments such as carbon black, carbon black, etc. By including a pigment in the insulating film, light of a specific wavelength from among the light penetrating from the surface side of the insulating film to the metal plate side can be reflected to the surface side by the insulating film. For example, when an OLED element is produced by using the insulating film laminated metal plate of the present invention and the OLED element is made to emit light, the light corresponding to the wavelength of the pigment among the light emitted from the light emitting layer to the metal plate side can be reflected to the insulating film Element surface side.

2-1. Thermosetting resin In the present invention, the thermosetting resin contains a polyester resin composed of a unit derived from a dicarboxylic acid and a unit derived from a polyol, and the unit derived from a dicarboxylic acid contains a unit derived from Units of terephthalic acid and units derived from isophthalic acid total 90 mol% or more. Units derived from polyols contain 90 mol% or more of units derived from polyols having 2 to 5 carbon atoms. The above are derived from terephthalic acid. The Mohr percentage of the unit derived from the dicarboxylic acid is 40 to 70%, and the Mohr percentage of the unit derived from the isophthalic acid is 30 to 60 in the unit derived from the dicarboxylic acid. %, And the adjusted average carbon number of the unit derived from the polyol calculated by the above formula (1) is 3.4 or less.

2-1-1. Polyester resin The above-mentioned polyester resin is a polymer substance having a plurality of ester bonds formed by a condensation reaction of a dicarboxylic acid and a polyhydric alcohol. The ester group constituting the ester bond is composed of only carbon atoms and oxygen. Atoms make it less compatible with water. Therefore, when an organic electronic device is manufactured using the insulating film laminated metal plate of the present invention, even if water which adversely affects the organic electronic device penetrates into the inside of the insulating film containing the polyester resin, it can be easily removed by drying. For example, when an organic EL device is produced as an organic electronic device by using the insulating film-laminated metal plate of the present invention, the occurrence of dark spots (non-light-emitting areas) caused by the penetration of water can be suppressed.

In the polyester resin described above, the molar percentage of the unit derived from terephthalic acid and the unit derived from isophthalic acid in the unit derived from dicarboxylic acid is 90% or more. The terephthalic acid which is a raw material of the unit derived from terephthalic acid and the isophthalic acid which is a raw material of the unit derived from isophthalic acid are aromatic dicarboxylic acids and are excellent in thermal stability. Moreover, these are cheaper than other aromatic dicarboxylic acids. Therefore, by setting the above-mentioned total mole percentage to 90% or more, relatively low cost, while ensuring heat resistance, and suppressing the occurrence of wrinkles when a conductive thin film layer is formed by sputtering. From the viewpoint of suppressing manufacturing costs, the above-mentioned total mole percentage is preferably 100%. Among units derived from a dicarboxylic acid, units derived from terephthalic acid and units derived from isophthalic acid can be identified by, for example, a nuclear magnetic resonance method (NMR method).

In the polyester resin described above, the molar percentage of units derived from terephthalic acid in units derived from dicarboxylic acids is 40 to 70%. The unit derived from terephthalic acid exhibits a structure in which the polyester resin is linearly elongated, and is a structural unit that suppresses the rotation of the polyester resin itself (rotation of the polyester resin molecules) and increases the hardness of the polyester resin. It can improve the hardness of the insulation film. From the viewpoint of ensuring the hardness of the insulating film, the mole percentage of the unit derived from terephthalic acid in the unit derived from dicarboxylic acid is set to 40% or more. Should be more than 50%. On the other hand, if the mole percentage of the unit derived from terephthalic acid in the unit derived from dicarboxylic acid is too high, the insulating film becomes too hard, and the workability of the insulating film laminated metal plate is reduced. Therefore, the mole percentage of the unit derived from terephthalic acid in the unit derived from dicarboxylic acid is set to 70% or less. Should be below 60%.

In the above-mentioned polyester resin, the molar percentage of the units derived from isophthalic acid in the units derived from dicarboxylic acid is 30 to 60%. The unit derived from isophthalic acid has a structure that bends the polyester resin, is a structural unit that facilitates rotation of the polyester resin itself (rotation of polyester resin molecules) and reduces the hardness of the polyester resin. It even has the effect of making the insulating film soft. From the viewpoint of ensuring the softness of the insulating film, the mole percentage of the unit derived from isophthalic acid in the unit derived from dicarboxylic acid is set to 30% or more. Should be above 40%. On the other hand, if the molar percentage of the unit derived from isophthalic acid in the unit derived from dicarboxylic acid is too high, the insulating film becomes too soft. Therefore, the molar percentage of the units derived from isophthalic acid in the units derived from dicarboxylic acid is set to 60% or less. Should be below 50%.

In the polyester resin described above, the mole percentage of the units derived from the polyol having 2 to 5 carbons to the units derived from the polyol is 90% or more. A unit derived from a polyol having a carbon number of more than 5 is a structural unit that reduces the hardness of the polyester resin described above. If the Mohr percentage exceeds 10%, the insulating film does not meet the required hardness, and conductivity is formed by sputtering. When a thin film layer is formed, wrinkles can occur. From the viewpoint of stably ensuring the hardness of the polyester resin, the molar percentage of the units derived from the polyol having 2 to 5 carbons to the units derived from the polyol is preferably 100%. Among the units derived from a polyol, the units derived from a polyol having 2 to 5 carbon atoms can be identified by, for example, a nuclear magnetic resonance method.

The polyester resin can be obtained by a condensation reaction of a dicarboxylic acid containing terephthalic acid and isophthalic acid and a polyol containing a polyhydric alcohol having 2 to 5 carbon atoms. Therefore, the dicarboxylic acid may contain dicarboxylic acid other than terephthalic acid and isophthalic acid. Examples of such dicarboxylic acids include α, β-unsaturated dibasic acids such as maleic acid, fumaric acid, and ikonic acid; or, for example, phthalic acid, tetrahydrophthalic acid, and hexahydrophthalic acid. Dicarboxylic acid, hexahydroisophthalic acid, hexahydroterephthalic acid, succinic acid, malonic acid, glutaric acid, adipic acid, lipoic acid, 1,10-decanedicarboxylic acid, 2,6- Saturated dibasic acids other than terephthalic acid and isophthalic acid, such as naphthalenedicarboxylic acid, 2,7-naphthalenedicarboxylic acid, 2,3-naphthalenedicarboxylic acid, 4,4'-biphenyldicarboxylic acid, and the like. Among them, it is preferable to use one or two or more of 2,6-naphthalenedicarboxylic acid, 2,7-naphthalenedicarboxylic acid, and 2,3-naphthalenedicarboxylic acid having a similar molecular structure to terephthalic acid and isophthalic acid.

On the other hand, the above-mentioned polyols include not only polyols having 2 to 5 carbon atoms, but also polyols having 6 or more carbon atoms. Examples of the polyhydric alcohol include ethylene glycols such as ethylene glycol, diethylene glycol, and polyethylene glycol; propylene glycols such as propylene glycol, dipropylene glycol, and polypropylene glycol; 2-methyl-1,3-propanediol; 1,3-butanediol, adduct of bisphenol A with propylene oxide or ethylene oxide, glycerol, trimethylolpropane, 1,3-propanediol, 1,2-cyclohexanediol, 1, 3-cyclohexanediol, 1,4-cyclohexanediol, p-xylylene glycol, dicyclohexyl-4,4'-diol, 2,6-decahydronaphthalene glycol, ginseng (2-hydroxyethyl) Isocyanurate and so on. The polyhydric alcohol having 2 to 5 carbon atoms and the polyhydric alcohol having 6 or more carbon atoms may be used alone, or two or more of them may be appropriately used in combination.

The polyhydric alcohol is preferably a diol, and the polyhydric alcohol having 2 to 5 carbons is preferably a diol having 2 to 5 carbons. The polyhydric alcohol is preferably a polyhydric alcohol having only 2 to 5 carbon atoms. Examples of the diol having 2 carbon atoms include ethylene glycol. Examples of the diol having 3 carbon atoms include 1,2-propanediol and 1,3-propanediol. Examples of the diol having 4 carbon atoms include 2-methyl-1,3-propanediol, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, and 2,3 -Butanediol. Examples of the diol having 5 carbon atoms include neopentyl glycol and 1,5-pentanediol.

Among the above-mentioned polyester resins, the adjusted average carbon number of the unit derived from the polyol calculated by the above formula (1) is 3.4 or less. In the course of completing the present invention, the inventors discovered that the adjusted average carbon number of the unit derived from the polyol is an index that can adjust the hardness of the insulating film at a temperature of about 200 to 250 ° C. Among the polyester resins, the polyol-derived unit has a chain hydrocarbon as a skeleton, and therefore has a property that the polyester resin is softer than the dicarboxylic acid-derived unit. If the adjusted average carbon number of the unit derived from the polyol exceeds 3.4, the proportion of the chain hydrocarbons in the polyester resin becomes large. As a result, the insulation film becomes soft at a temperature of about 200 to 250 ° C. Wrinkles occur when a conductive thin film layer is formed by sputtering. The smaller the adjusted average carbon number of the unit derived from the polyol, the more the occurrence of wrinkles when the conductive thin film layer is formed by sputtering is suppressed. The adjusted average carbon number of the unit derived from the polyol is preferably 3.2 or less, and more preferably 3.0 or less. However, methyl glycol of a polyhydric alcohol having a carbon number of 1 is not stable. Therefore, a substantial lower limit value of the adjusted average carbon number of the unit derived from the polyhydric alcohol is 2.0.

The average carbon number of the unit derived from a polyol in the above formula (1) refers to the number of carbons of the unit derived from an individual polyol among the units derived from the polyol multiplied by the mole ratio of the unit derived from the individual polyol. The sum of the values. For example, the unit A derived from the polyhydric alcohol is composed of the unit A1 of the individual polyol derived from the carbon number N1 with a mole percentage of X1 and the unit derived from the individual polyol derived from the carbon number N2 with a molar percentage of X2. In the case of A2, the average carbon number N of the unit A derived from the polyol is calculated as (N1 × X1 + N2 × X2) / 100. The carbon number of the unit derived from the individual polyol refers to the total number of carbons contained in the unit derived from the individual polyol, and is the sum of the carbon number of the main chain and the carbon number of the side chain of the unit derived from the individual polyol.

Although 2-methyl-1,3-propanediol and 1,4-butanediol have the same total carbon number of 4, each is a polyol having 3 to 4 carbon atoms in the main chain, which are different. Experiments by the present inventors have confirmed that in an insulating film laminated metal plate produced using a polyol containing these polyols individually, the wrinkles that occur when the conductive thin film layer is formed are the same degree.

2-1-2. Crosslinking agent In the present invention, the thermosetting resin contains a crosslinking agent. Thereby, the insulating film not only exhibits thermosetting property, but also improves heat resistance. In addition, when an organic electronic device is manufactured using the insulating film laminated metal plate of the present invention, deformation or deterioration of the insulating film can be suppressed.

The cross-linking agent is not particularly limited as long as it can cross-link the polyester resin, and is preferably one having good compatibility with the polyester resin and good liquid stability. Such a cross-linking agent is suitably used for various commercial products. Examples of isocyanates include MILLIONATE (registered trademark) N, CORONATE (registered trademark) T, CORONATE (registered trademark) HL, CORONATE (registered trademark) 2030, SUPRASEC (registered trademark) 3340, DULT SEC 1350, DULT SEC 2170, DULT SEC 2280 (the above is made by Japan Polyurethane Industry Co., Ltd.), etc. For the melamine type, NIKALAC (registered trademark) MS-11, NIKALAC (registered trademark) MS21 (the above is made by Sanwa Chemical Co., Ltd.), SUPER BECKAMINE (registered trademark) L-105-60, SUPER BECKAMINE (registered trademark) J-820-60 (above are manufactured by DIC Corporation), and for epoxy systems, HARDENER HY951, HARDENER HY957 (above, manufactured by BASF) , SUMICURE DTA, SUMICURE TTA (the above are made by Sumitomo Chemical Co., Ltd.) and so on.

The content ratio of the polyester resin and the crosslinking agent in the thermosetting resin is not particularly limited, and the content ratio of the polyester resin is preferably 50% by mass or more.

2-2. Pigment white pigments, such as titanium oxide, calcium carbonate, zinc oxide, barium sulfate, zinc barium white, lead white, and other inorganic pigments, such as polyethylene, polystyrene, polyacrylate, and urea resin can be used. And organic pigments such as melamine resin. Among these, it is preferable to use pure white titanium oxide. By including a white pigment in the insulating film, the luminance of the organic EL element produced by using the insulating film laminated metal plate of the present invention is improved.

As the black pigment, for example, black: organic pigments such as aniline black and nigrosine black, or inorganic pigments such as carbon black and iron black can be used. By including a black pigment in the insulating film, the darkness of the organic EL element produced by using the insulating film-laminated metal plate of the present invention at the time of non-emission will increase.

As the red pigment, for example, insoluble azo-based (naphthol-based and amidobenzene-based) or soluble azo-based organic pigments, or inorganic pigments such as iron dan, cadmium red, and lead dan can be used. As the yellow pigment, for example, organic pigments such as insoluble azo-based (naphthol-based and amidobenzene-based), soluble azo-based, quinacridone-based, or, for example, chrome yellow, cadmium yellow, nickel titanium yellow, and yellow dan And inorganic pigments such as strontium chromate. As the green pigment, for example, an organic phthalocyanine pigment can be used. As the blue pigment, for example, an organic pigment such as an organic phthalocyanine pigment, a dioxazine pigment, Prussian blue, ultramarine blue, cobalt blue, or emerald green can be used. Orange, for example, organic pigments such as benzimidazolone and pyrazolone can be used.

2-3. Surface roughness of the insulating film 皮 In the present invention, a suitable thickness of the insulating film is 10 to 50 μm. On the other hand, when an organic electronic device is manufactured using the insulating film laminated metal plate of the present invention, a suitable thickness of the conductive thin film layer formed on the insulating film is 0.01 to 1 μm, as described later. In this way, since the thicknesses of the two are greatly different, the conductive thin film layer having a small thickness is affected by the insulating film having a large thickness, and quality defects are liable to occur. For example, if there are defects such as pinholes on the surface of the insulating film, water easily penetrates and dark spots easily occur. In addition, if the surface of the insulating film is uneven, the thickness of the conductive thin film layer formed on the convex portion of the insulating film is likely to be different from the thickness of the conductive thin film layer formed on the concave portion of the insulating film. Impact on quality or life. From the viewpoint of avoiding this problem, the surface roughness of the 3 mm square region of the insulating film is preferably 10 nm or less, more preferably 5 nm or less, and even more preferably 3 nm or less. This also suppresses fluctuations in the insulating film.

The surface roughness of the 3 mm square area can be measured by a measurement method described later.

A method of reducing the surface roughness of the 3 mm square region of the insulating film to 10 nm or less includes a method of performing chemical mechanical polishing (CMP) on the surface of the insulating film. This makes the surface of the insulating film smooth.

The chemical mechanical polishing method is not particularly limited, and any known polishing method may be used as long as it is polished by the surface chemical action of the abrasive itself or the action of the chemical components contained in the polishing solution. The abrasive is not particularly limited, and examples thereof include silicon dioxide, aluminum oxide, cerium oxide, titanium dioxide, zirconium dioxide, and germanium dioxide.

[Manufacturing Method of Insulating Film Laminated Metal Plate] Next, the manufacturing method of the above-mentioned insulating film laminated metal plate will be described.

The insulating film is preferably laminated by a coating method in which a composition for producing an insulating film is coated on the surface of a metal plate or another layer. Therefore, it is desirable that the composition for producing an insulating film is liquid and further contains a solvent. The solvent used for the composition for producing an insulating film is not particularly limited as long as it can dissolve or disperse each component which is required for the composition for producing an insulating film. Examples of the solvent include alcohols such as methanol, ethanol, n-propanol, isopropanol, n-butanol, isobutanol, and ethylene glycol; acetone, methyl ethyl ketone, methyl isobutyl ketone, and cyclohexane Ketones such as ketones; aromatic hydrocarbons such as toluene, benzene, xylene, Solvesso (registered trademark) 100 (manufactured by Exxon Mobil), Solvesso (registered trademark) 150 (manufactured by Exxon Mobil); hexane, heptane , Aliphatic hydrocarbons such as octane; esters such as ethyl acetate, butyl acetate; etc. The composition for producing an insulating film can be adjusted to a solid content using, for example, the above-mentioned solvent.

The coating method of the composition for producing an insulating film is not particularly limited, and a known method can be suitably used. The coating method includes, for example, a pre-coating method using a bar coating method, a roll coating method, a curtain coating method, a spray method, and a spray wring method. Among these, from the viewpoints of cost and the like, a bar coating method, a roll coating method, a spray method, and a spray wring method are preferable. For example, when the pre-coating method is used, the baking temperature is preferably 190 ° C to 250 ° C, and more preferably 200 ° C to 240 ° C. The drying temperature may be such that the insulating film does not deteriorate due to heat. For example, it is preferably about 190 to 250 ° C, and more preferably about 200 to 240 ° C. The baking temperature and drying temperature only need to use the highest plate temperature (Peak Metal Temperature: PMT).

The manufacturing method of a polyester resin and an insulating film laminated metal plate is as follows, for example.

It contains a dicarboxylic acid and a polyhydric alcohol at a molar ratio of 1: 1.5 to 2, the dicarboxylic acid contains terephthalic acid and isophthalic acid in a total amount of 90 mol% or more, and the polyhydric alcohol contains a polyvalent carbon number of 2 to 5 To the polyester resin forming composition having an alcohol of 90 mol% or more, antimony trioxide was added as a catalyst, and the reaction was heated at atmospheric pressure and at 180 to 210 ° C. for 180 minutes to cause a condensation reaction. Next, the temperature was raised to 250 ° C. and the pressure was reduced to 1 to 5 mmHg, and then a condensation reaction was further performed for 180 minutes, and water generated by the condensation reaction was removed. Thereby, a polyester resin can be obtained. In the condensation reaction with the removal of water in the second half, the polyhydric alcohol is volatilized. Therefore, in the obtained polyester resin, the unit derived from the dicarboxylic acid and the unit derived from the polyhydric alcohol are slightly 1: 1. The precise loading of the dicarboxylic acid and polyol can be determined based on the units derived from the dicarboxylic acid and the polyol derived from the polyester resin obtained by changing the composition for forming the polyester resin from the content ratio of the dicarboxylic acid and the polyol. The Morse ratio of the unit is determined.

The obtained polyester resin, a cross-linking agent, and pigments added as necessary are dissolved in a solvent and dispersed, and the obtained solution (the composition for producing an insulating film) is applied to a metal plate and heated. Thereby, an insulating film is formed on a metal plate, and an insulating film laminated metal plate can be obtained. When the solution is prepared, the content of solid components (polyester resin, crosslinking agent, pigment, etc.) is preferably 20 to 70% by mass. When the solid content is less than 20% by mass, the viscosity of the solution becomes too low, and the coating must be repeatedly applied multiple times to achieve the target thickness of the insulating film. On the other hand, when the content of the solid content exceeds 70% by mass, the viscosity of the solution becomes too high, and it is difficult to perform the coating itself. The pigment ratio in the solid content is preferably 60% by mass or less. When the ratio of the pigment in the solid content exceeds 60% by mass, the viscosity of the solution becomes too high, and it is difficult to perform the coating itself.

[Metal Substrate] Next, a metal substrate according to another aspect of the present invention will be described.

The metal substrate of the present invention is a metal substrate in which a conductive thin film layer is laminated on the insulating film included in the insulating film laminated metal plate.

In the present invention, the conductive thin film layer is made of ZnO, ITO, or SnO _{2 to} which, for example, Al, B, Ga, or Sb is added. It is usually made of ITO.

The layer structure of the conductive thin film layer may be a single-layer structure or a laminated structure of two or more layers. The substances constituting each layer (that is, the above-mentioned ZnO, ITO, or SnO ₂ ) may be the same or different.

The thickness of the conductive thin film layer is not particularly limited, but is preferably 0.01 to 1 μm.

The surface roughness of the 3 mm square region of the conductive thin film layer is preferably 100 nm or less, more preferably 20 nm or less, more preferably 10 nm or less, and even more preferably 5 nm or less. Thereby, a solar cell with high power generation efficiency or an organic EL element with high light emission illuminance can be manufactured. The surface roughness of the 3 mm square area can be measured by a measurement method described later.

Since the conductive thin film layer has heat resistance of about 200 ° C or higher, an organic electronic device can be manufactured using the metal substrate of the present invention.

In the organic EL element produced using the metal substrate of the present invention, the conductive thin film layer functions as an anode. In addition, since the conductive thin film layer is transparent, light emitted from the light emitting layer to the metal plate side is reflected by the pigment-containing insulating film located under the conductive thin film layer.

[Method for Manufacturing Metal Substrate] Next, a method for manufacturing the above-mentioned metal substrate will be described.

The conductive thin film layer can be formed by sputtering. More specifically, the insulating film laminated metal plate of the present invention is placed in a vacuum container, and a metal or a metal oxide to be provided in the form of a thin film is set as a target. For example, when an ITO layer is formed as the conductive thin film layer, a target made of ITO is used. Then, a high voltage is applied to a rare gas element such as argon or nitrogen to ionize it and collide with the target. As a result, atoms and the like on the target surface are bombarded, reach the insulating film laminate metal plate, and form a conductive thin film layer on the insulating film.

[Bottom-type thin-film solar cell] Next, a bottom-type thin-film solar cell including the insulating film-laminated metal plate of the present invention will be described.

As long as the bottom plate type solar cell is provided with the insulating film laminated metal plate of the present invention, any known structure may be used. For example, basically, the insulating film of the insulating film laminated metal plate of the present invention is sequentially layered. Structure of back electrode, photoelectric conversion layer and front electrode. The photoelectric conversion layer is a layer that absorbs the light reaching through the transparent surface electrode and generates a current. Either the back electrode or the surface electrode is used to take out the current generated by the photoelectric conversion layer. It is made of a conductive material. The surface electrode on the light incident side must have translucency. Regarding the back electrode, the photoelectric conversion layer, and the front electrode, the same materials as those of a well-known bottom plate type thin-film solar cell can be used.

In the bottom plate type solar cell, since sunlight is incident from the transparent surface electrode side, the transparency of the insulating film laminated metal plate is not required.

[Top-Emitting Organic EL Element] Next, a top-emitting organic EL element including the insulating film laminated metal plate of the present invention will be described.

The top-emitting organic EL element may have any of the known structures as long as it includes the insulating film-laminated metal plate of the present invention. For example, the insulating film provided by the insulating film-laminated metal plate of the present invention is basically A structure in which an anode, a light-emitting layer, and a cathode are laminated in this order. As the anode, the light-emitting layer, and the cathode, the same materials as those of a well-known top-emission thin-film solar cell can be used.

In the top emission type organic EL element, light passes through the cathode (and does not pass through the insulating film laminated metal plate) and is emitted. Therefore, an opaque metal plate can be used as the substrate.

As described above, one aspect of the present invention is an insulating film laminated metal plate comprising a metal plate and an insulating film laminated on at least one side of the metal plate, the insulating film contains a thermosetting resin, and the thermosetting The polyester resin contains a polyester resin which is composed of a dicarboxylic acid-derived unit and a polyhydric alcohol-derived unit, and the dicarboxylic acid-derived unit includes a terephthalic acid-derived unit and an isophthalic acid-derived unit. The total unit is 90 mol% or more. The unit derived from the polyol contains 90 mol% or more of the unit derived from a polyhydric alcohol having 2 to 5 carbon atoms. The terephthalic acid-derived unit occupies the dicarboxylic acid-derived unit. The Mohr percentage of the unit is 40 to 70%, and the Mohr percentage of the isophthalic acid-derived unit to the dicarboxylic acid-derived unit is 30 to 60%. Calculated by the above formula (1) The adjusted average carbon number of the unit derived from the polyol is 3.4 or less, and is used to form a conductive thin film layer on the insulating film.

According to this configuration, when a conductive thin film layer is formed on the insulating film by sputtering, softening due to an increase in the temperature of the insulating film is suppressed, so that a conductive thin film layer capable of suppressing occurrence of wrinkles can be formed. Furthermore, the surface of the light-emitting layer of the organic EL element produced by using the insulating film-laminated metal plate of the present invention emits light uniformly.

In the insulating film laminated metal plate of the present invention, the insulating film may further contain a pigment. With this structure, the organic EL element produced by using the insulating film-laminated metal plate of the present invention reflects the light having a wavelength corresponding to the pigment to the surface of the element in the insulating film, so that the light with the wavelength can be increased. Related brightness.

In the insulating film laminated metal plate of the present invention, the surface roughness of the 3 mm square region of the insulating film is preferably 10 nm or less. With this configuration, the surface of the insulating film becomes smooth, and in a practical range, occurrence of dark spots can be suppressed. In addition, by using the insulating film-laminated metal plate of the present invention, a solar cell with high power generation efficiency or an organic EL element with high illuminance can be manufactured.

Another aspect of the present invention is a metal substrate in which a conductive thin film layer is laminated on an insulating film included in the insulating film laminated metal plate.

According to this configuration, the organic EL element produced using the metal substrate of the present invention is less likely to have color spots or insufficient luminous illuminance. On the other hand, the solar cell produced using the metal substrate of the present invention is unlikely to reduce power generation.

In the metal substrate of the present invention, the surface roughness of the 3 mm square region of the conductive thin film layer is preferably 100 nm or less. With this configuration, the surface of the conductive thin film layer becomes smooth, and in a practical range, an organic EL element or a solar cell with stable quality and life can be produced.

The metal substrate of the present invention can be used for a top emission organic EL element or a bottom plate type thin film solar cell. With this configuration, a top emission organic EL element with stable starting illuminance or a bottom plate type thin-film solar cell with stable power generation can be manufactured.

According to the present invention, it is possible to provide an insulating film laminated metal plate capable of suppressing occurrence of wrinkles when a conductive thin film layer is formed by sputtering, and a metal substrate in which occurrence of wrinkles on the surface of the conductive thin film layer is suppressed. [Example]

Examples are given below to more specifically explain the present invention. In addition, the present invention is not limited to the following examples, and can be implemented by being modified within a scope that meets the gist of the foregoing and the following, and any of them is included in the technical scope of the present invention.

[Production of Polyester Resin] In an autoclave equipped with a stirring device and a thermometer, the raw material monomer of the polyester resin shown in Table 1 No. 1 (filling amount: 83.0 parts by mass of terephthalic acid, between 83.0 parts by mass of phthalic acid, 107.2 parts by mass of ethylene glycol, 44.8 parts by mass of neopentyl glycol), and 0.1 part by mass of antimony trioxide were heated at atmospheric pressure and 180 to 210 ° C. for 180 minutes to cause a condensation reaction. Next, the temperature was raised to 250 ° C. and the pressure was reduced to 1 to 5 mmHg, and then a condensation reaction was further performed for 180 minutes. Thereby, the polyester resin of No. 1 was obtained.

According to the composition ratio of each structural unit of the polyester resin of No. 1 measured by NMR method, the molar percentage of the unit derived from terephthalic acid in the unit derived from dicarboxylic acid was 50%, and The molar percentage of units of phthalic acid in the units derived from dicarboxylic acids is 50%, the molar percentage of units from ethylene glycol units in the units derived from polyols is 80%, and the units derived from neopentyl hydroxyl The mole percentage of the acetic acid unit in the unit derived from the polyol is 20%.

Next, among the production conditions of the polyester resin of No. 1, only the amount of the raw material monomer was changed from the raw material monomer of the polyester resin of No. 1 to No. 2 to No. 9 of Table 1 respectively. The raw material monomers of the polyester resin shown are polyester resins Nos. 2 to 9 respectively. Then, the composition ratio of each structural unit of the polyester resins of Nos. 2 to 9 was obtained by the NMR method. The results are shown in Table 1.

For polyester resins Nos. 1 to 9, the average percentage of units derived from the polyol was calculated from the mole percentage of each unit derived from the polyol and the number of carbons of each unit obtained by the NMR method. Carbon number. Then, the adjusted average carbon number of the unit derived from the polyol is calculated from the average carbon number of the unit derived from the polyol and the mole percentage of the unit derived from the terephthalic acid in the unit derived from the dicarboxylic acid. These calculation results are also shown in Table 1.

[Production of a composition for producing an insulating film] (1) A polymer of No. 1 was added to a solvent in which xylene (boiling point: 140 ° C) and cyclohexanone (boiling point: 156 ° C) were mixed in equal amounts little by little. 43.4 parts by mass of the ester resin in terms of solid content, 14.5 parts by mass of the melamine resin (SUPER BECKAMINE (registered trademark) J-820-60 manufactured by DIC Corporation) in terms of solid content, titanium oxide particles (Ishihara Industry Co., Ltd. TIPAQUE (registered trademark) CR-50 (average particle size 0.25 μm) manufactured by Co., Ltd. is 16.0 parts by mass in terms of solid content, and 0.3 parts by mass of triethylenediamine manufactured by Tokyo Chemical Industry Co., Ltd. .1 A composition for producing an insulating film. In addition, the amount of the mixed solvent of xylene and cyclohexanone was adjusted so that the total solid content of the polyester resin and the melamine resin became 58% by mass.

Next, among the production conditions of the composition for producing an insulating film of No. 1, only the blended polyester resin was changed from the polyester resin of No. 1 to the polyester resin of Nos. 2 to 9, respectively. Compositions for producing insulating films Nos. 2 to 9 were obtained.

[Production of Insulated Film Laminated Metal Plate] As a metal plate, a plated pure zinc steel plate having a thickness of 0.8 mm and a galvanized adhesion amount of 20 g / m ² on each of the two sides of the metal plate was used. The composition for producing the insulating film No. 1 was applied with a bar coater so that the film thickness became 15 μm. Then, it baked for 2 minutes so that the highest board temperature might become 220 degreeC, and it was made to dry, and the insulation film laminated metal plate of No. 1 was obtained.

Next, among the manufacturing conditions of the insulating film laminated metal plate of No. 1, only the composition for producing the coated insulating film was changed from the composition for producing the insulating film of No. 1 to No. 2 to 9 respectively. Compositions for the production of insulating films were obtained as insulating film laminated metal plates of Nos. 2 to 9, respectively.

[Surface Polishing of Insulating Film Laminated Metal Plate] The No. 1 insulating film laminated metal plate was set on a jig with a substrate mounting suction pad attached to a polishing device, with the insulating film facing downward, and installed on the polishing surface. The device's platen is on a polishing pad. Chemical-mechanical polishing using alumina particles with a particle size of about 100 nm as an abrasive, a pressure of 65 gf / cm ² , a rotation distance of 1 m per week, and an insulation film laminated metal plate and a fixed plate of No. 1 at a speed of 50 rpm 1 minute.

Next, under the same conditions as the surface polishing conditions of the insulating film laminated metal plate of No. 1, the surface polishing of the insulating film laminated metal plates of Nos. 2 to 9 was performed.

[Production of Metal Substrate] The surface of the insulating film was chemically and mechanically polished, and the insulating film laminated metal plate of No. 1 was washed in the following procedure. That is, firstly, the insulating film laminated metal plate of No. 1 was washed with ultrapure water, and then ultrasonically washed with ultrapure water at 23 kHz for 3 minutes, and then was washed with an organic-based impurity-removing lotion at 23 kHz. Sonic washing for 3 minutes, followed by washing with ultrapure water, and then using ultrasonic cleaning at 43kHz for 3 minutes, then washing with ultrapure water, and then using ultrapure water at 1MHz Ultrasonic washing was performed for 3 minutes, followed by isopropanol vapor washing, and UV ozone washing was performed just before the ITO layer was formed. Next, a ITO layer having a thickness of 100 nm was formed on the insulating film under a sputtering condition of 300 W to obtain a metal substrate of No. 1.

Next, among the manufacturing conditions of the metal substrate of No. 1, only the metal substrate was changed from the metal substrate of No. 1 to the metal substrate of Nos. 2 to 9 to obtain the metal substrates of Nos. 2 to 9 respectively.

[Judgment of Wrinkles] For metal substrates Nos. 1 to 9, using an atomic force microscope (Atomic Force Microscope 1 AFM) (SPI3800N manufactured by SEIKO Electronics Industries), the presence or absence of wrinkles was determined according to the following determination conditions.

(Judging conditions for the presence or absence of wrinkles) 观察 Using an atomic force microscope to observe the surface of the ITO layer of the metal substrate, convex groups of 20 to 50 μm in length, 5 to 10 μm in width, and 100 nm or more in height were observed in a 100 μm square area on the surface of the ITO layer. Wrinkles were judged, and if not observed, it was judged as no wrinkles.

The determination results are shown in Table 1.

FIG. 2 is an atomic force microscope image of the surface of the ITO layer in the metal substrate of No. 1, showing that the surface of the ITO layer has no wrinkles. FIG. 3 is an atomic force microscope image of the surface of the ITO layer in the metal substrate of No. 2 and shows that the surface of the ITO layer has wrinkles.

[Measurement of the surface roughness of a 3 mm square area] For each of the insulation films of the insulation film laminated metal plates No. 1 to 9 subjected to surface polishing, the above-mentioned atomic force microscope was used to measure the Surface roughness Ra '. In addition, each of the ITO layers of the metal substrates Nos. 1 to 9 was also used to measure the surface roughness Ra ′ of a 3 mm square region using the above atomic force microscope.

(Measurement method of the surface roughness of a 3 mm square area) Using an atomic force microscope, measure the 10 μm square area at the four corners of the 3 mm square area and 5 locations in the center according to the definition of the arithmetic mean roughness specified in JIS B 0601. The arithmetic mean roughness Ra1 in one direction and the arithmetic mean roughness Ra2 in a direction perpendicular thereto. Then, the average value of Ra1 and Ra2 was determined as the surface roughness Ra3 of the 10 μm square region. Then, the average value of the surface roughness Ra3 of the 10 μm square region at the above five locations was determined as the surface roughness Ra ′ of the 3 mm square region.

The measurement results are shown in Table 1.

[Evaluation of Insulating Film Laminated Metal Plates and Metal Substrates of Nos. 1 to 9] Insulating film laminated metal plates and metal substrates of Nos. 1 to 5 to 7 are examples that satisfy various conditions specified in the present invention. These examples represent that there is no wrinkle on the surface of the ITO layer, and the surface roughness Ra 'of the 3 mm square area is 100 nm or less.

On the other hand, the insulating film laminated metal plates and metal substrates of Nos. 2 to 4, 8, and 9 are examples that do not satisfy the condition stipulated in the present invention "the average carbon number of the unit derived from the polyol is 3.4 or less". . These examples represent wrinkles on the surface of the ITO layer, and the surface roughness Ra 'of the 3 mmn square area exceeds 100 nm.

This application is based on Japanese Patent Application No. 2017-068818 filed on March 30, 2017, and its contents are included in the present invention.

In order to express the present invention, in the above-mentioned content, the present invention has been appropriately and fully explained through the embodiments. However, it should be understood that as long as a person skilled in the art can change and / or improve the embodiments described above. Therefore, as long as the change form or improvement form implemented by those in the industry does not depart from the scope of the right of the claims described in the scope of the patent application, the change form or the improved form can be interpreted as being included in the scope of rights of the request. .

FIG. 1 is a schematic substitute photograph of an optical microscope image showing a light-emitting state of a surface of a top emission organic EL element produced using a conventional insulating film laminated metal plate. FIG. 2 is a schematic substitute photograph showing an atomic force microscope image of the surface of the ITO layer in the metal substrate of No. 1 in Example. FIG. 3 is a schematic substitute photograph showing an atomic force microscope image of the surface of the ITO layer in the metal substrate of No. 2 in Example.

Claims (6)

An insulating film laminated metal plate comprising a metal plate and an insulating film laminated on at least one side of the metal plate, the insulating film contains a thermosetting resin, the thermosetting resin contains a polyester resin, and the polyester The resin is composed of a unit derived from a dicarboxylic acid and a unit derived from a polyol. The unit derived from a dicarboxylic acid contains a unit derived from terephthalic acid and a unit derived from isophthalic acid. The unit contains 90 mol% or more of units derived from a polyhydric alcohol having 2 to 5 carbon atoms, and the molar ratio of the terephthalic acid-derived units to the dicarboxylic acid-derived units is 40 to 70%. The molar percentage of the units derived from isophthalic acid in the aforementioned dicarboxylic acid-derived units is 30 to 60%. The adjusted average carbon number of the polyol-derived units calculated from the following formula (1) is 3.4 or less, and used to form a conductive thin film layer on the insulating film [Mathematical formula 1] . The insulating film laminated metal plate according to claim 1, wherein the aforementioned insulating film further contains a pigment. For example, the insulating film laminated metal plate of claim 1 or 2, wherein the surface roughness of the 3 mm square region of the foregoing insulating film is 10 nm or less. A metal substrate in which a conductive thin film layer is laminated on an insulating film included in an insulating film laminated metal plate according to any one of claims 1 to 3. The metal substrate according to claim 4, wherein a surface roughness of a 3 mm square region of the conductive thin film layer is 100 nm or less. If the metal substrate of claim 4 or 5 is used, it is used in a top emission organic EL element or a bottom plate type thin film solar cell.