KR101321628B1 - Plastic substrate and element containing the same - Google Patents

Abstract

The present invention discloses a plastic substrate comprising a plastic film, a reflective and / or electrically conductive metal film, and a resin layer in which a conductive material is dispersed. This is useful as a lower substrate of a transmissive electronic paper display device and a display device.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a plastic substrate,

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a plastic substrate and a device including the plastic substrate, and more particularly to a plastic substrate and a transparent electrode for an electronic paper display device and a display device.

Most liquid crystal display devices, as well as electronic paper display devices and liquid crystal display devices, have conventionally used glass substrates as the upper and lower substrates, and the thickness of the upper and lower glass substrates is gradually decreasing to realize weight reduction. However, despite the fact that the thickness of the substrate is now at its limit, it is difficult to obtain a satisfactory light weight. Therefore, a study has been made to change the material of the substrate. As a part of this, a technique of using a plastic substrate .

However, the plastic substrate may suffer from thermal, chemical, and mechanical damages during the array pattern forming process, the color filter forming process, and the like, thereby degrading the image quality characteristics of the liquid crystal display.

An example of a liquid crystal display device generally including a plastic substrate is briefly illustrated in FIG. 1A, specifically, upper and lower substrates 1 formed of plastic; Upper and lower electrodes (11) formed of transparent electrodes by applying a driving voltage of the device on the upper and lower substrates; A barrier rib (140) formed in a two-layer structure to keep the gap between the upper and lower substrates constant; And a charged particle or liquid crystal layer 150 injected into the cell formed by the barrier rib particles. A polarizing plate formed on an outer surface of a plastic insulating substrate used as an upper substrate, and a reflective plate and a transmissive substrate formed on an outer surface of the lower substrate. A black matrix may be formed on the upper plastic insulating substrate to define unit pixels. And a color filter may be provided in a space surrounded by the black matrix. On the other hand, a switching element and a pixel electrode may be provided for each unit pixel on the lower substrate.

1 (b) to 1 (c) show a cross-sectional view of an organic EL element as an example of another flat panel display device. In addition, a transparent electrode 110 or a reflective electrode 113 is formed on a substrate 1 Lt; / RTI >

Though the thickness of the device is thinned and lightened by introducing the plastic substrate, efforts to reduce the thickness and weight of the device by integrating various functions while suppressing deterioration of the image quality of the final application product are still required.

On the other hand, in the reflective liquid crystal display device, since illuminance is obtained by reflecting external light, a reflective material for diffusing and reflecting external light is provided. According to the aspect provided with a reflector, there exist an external reflector system which forms a reflector in the surface on the opposite side to the liquid-crystal layer side of a board | substrate, and the internal-attachment reflector system which forms a reflector in the liquid crystal layer side surface of a board | substrate.

In the external reflector method, since the reflector is formed on the opposite side of the liquid crystal layer side of the substrate, light incident from the outside is diffusely reflected by the reflector, and the reflected light passes through the substrate and then passes through the liquid crystal layer to exit from the display screen. do. At this time, parallax occurs because the reflected light is affected by the thickness of the substrate, which causes an image blur such as a double display of the liquid crystal display or a mixed color display.

On the other hand, in the internal reflection material method, since the reflection material is formed on the surface of the liquid crystal layer side of the substrate, light incident from the outside is diffusely reflected by the reflection material, and the reflected light passes through the liquid crystal layer without passing through the substrate, It is emitted to the outside. In this case, since the reflecting material and the liquid crystal layer are close to each other, and the reflected light is not affected by the substrate thickness, parallax does not occur and image blurring does not occur.

When a board | substrate is a plastic board | substrate, ie, when a film is used, thickness can be made thinner than glass, and the parallax hardly arises by that much. However, when a color filter is provided, one pixel is divided into color dots of a third size, so that the reflected light is more likely to pass through other dots than in the case of a single color, and the influence of the film thickness cannot be ignored.

Therefore, even when a film is used as the substrate, in particular, in the colored liquid crystal display device, there is a need to configure the reflector in an internally-attached reflector method.

However, there is a fear that the liquid crystal display device of the internal reflection reflecting method is complicated in structure and difficult to manufacture. In particular, when the film is used as the substrate, the film is easily stretched due to the influence of heat and humidity, and the conditions of the material and the manufacturing process are limited. For this reason, the manufacturing method which can manufacture the liquid crystal display device of the internal reflection reflector system which used the film as a board | substrate according to a design request | requirement can reduce cost and high yield.

In addition, the conventional reflective or semi-transmissive liquid crystal display manufacturing method of the reflective material is formed by photolithography using a photomask to form irregularities on the surface of the resin such as a resist film and to easily reflect light on the uneven surface. A method of forming a film to form a reflector has been proposed.

As another method of forming the irregularities on the surface of the resin, a method of forming the irregularities by the resin in which fine particles are dispersed (Japanese Patent Laid-Open No. H4-267220), phase separation at the time of curing the resin comprising two different components The method of forming an unevenness | corrugation by using it, and the method of forming an unevenness | corrugation by controlling the internal stress at the time of hardening of a light thermosetting resin material, and the like (JP-A-12-171792) are known.

However, when the electrode base material of the liquid crystal display device of the internal reflection type system using a film as a base material is produced by directly forming a reflector etc. on a film, there exist the following problems; Since the reflector needs the function to diffuse-reflect external light, the surface is provided with irregularities. Since this unevenness | corrugation is made by making the surface of a liquid crystal layer into unevenness, there exists a possibility that it may adversely affect liquid crystal drive. For this reason, the technique which performs a high leveling plan especially is needed, a cost rises and there exists a possibility that a yield may fall. Moreover, after forming the metal film used as a reflector, the chemical | medical agent process in the formation process of transparent electrodes etc. may cause damage to the reflector formed previously. In addition, since the film is used as the base material, the film is easily stretched under the influence of heat and humidity, and materials and manufacturing conditions such as reflectors and transparent electrodes are limited. It becomes difficult. In addition, the above-described problem may be further exacerbated when the electrode substrate of the transflective liquid crystal display device, which can use both the backlight and the reflected light by external light, is formed by directly forming a reflector or the like on the film.

In the case of forming the reflector therein, first, a reflector made of a metal film is formed on the entire surface of the plastic film, and then the pixel of the reflector part made of a metal film corresponding to the part of the pixel of the transparent electrode formed in a subsequent step is applied to the pixel. It is necessary to remove the reflective material of the metal film precisely so that the backlight can transmit the area smaller than the area of the portion to be made.

Then, when forming a transparent electrode above a reflector, the ITO used as a transparent electrode is formed into a film so that the part used as the pixel of a transparent electrode may overlap with the part which removed the reflector made of the metal film, and a resist film is formed on this ITO. It is necessary to adjust the position precisely, to expose and develop the resist film, to remove ITO, and to form a pattern of the transparent electrode. In this case, a high degree of positioning technology is required.

However, in the film made of plastic, elongation occurs only by performing a water washing treatment, and when it is dried, shrinkage occurs in reverse. In addition, these expansion and contraction is not stabilized immediately, but it takes a long time to stabilize. That is, once the film shrinks, the dimension of the pattern formed on the film causes elongation for a long time, making it difficult to obtain reproducibility related to alignment as described above.

Therefore, it is difficult to manufacture a transflective liquid crystal display device by directly forming a reflector, a transparent electrode, etc. on a film.

In addition, the conventional method of manufacturing a reflector of a reflective (transflective) type liquid crystal display device has the following problems.

In the method of forming irregularities on the surface of a resin such as a resist film by photolithography, the reflective material acts as a diffraction grating when the pattern of irregularities of the reflective material is simply repeated in the planar direction. Display defects may occur, such as color development in rainbow colors or subtle differences in positional relationships with other repetitive patterns such as wiring and black matrices, so-called moire stripes. For this reason, in the design of the photomask for forming the uneven pattern, it is not possible to use a simple repetitive pattern like a normal pixel pattern, and it is necessary to perform a complicated and difficult design. As such, it is not easy to form a reflector having a suitable diffusivity by ordinary photolithography.

In addition, the method of Unexamined-Japanese-Patent No. 4-267220 is disperse | distributing particle | grains of material different from the resin in resin, and the method of Unexamined-Japanese-Patent No. 12-193707 is phase separation at the time of hardening two different resins. The method disclosed in Japanese Patent Laid-Open No. 12-171792 discloses that part of the surface side of the resin is cured and exposed or baked so as to be uncured, thereby forming irregularities. When the reflective material is directly formed on a plastic film having a film thickness of 50 to 200 µm by such a conventional method for producing a reflective material, warpage is likely to occur in the plastic film due to the stress at the time of curing the resin.

In addition, the reflecting material manufactured by the above-mentioned manufacturing method is comprised from the material with which refractive index differs substantially with the interface of resin and particle | grains, or the interface separated from each other. When the uneven surface of the reflecting material is formed on the surface on the opposite side of the liquid crystal layer side of the electrode substrate, incident light polarized on the polarizing plate is reflected by the metal film after passing through the interface of the material with different refractive indexes of the reflecting material through the liquid crystal layer.

At this time, the polarization extinction effect which the polarization degree of light falls easily arises because polarized incident light and the reflected light scattered from the metal film are refracted at the interface of materials with different refractive index. Thereby, when applying the reflecting material arrange | positioned with the structure as mentioned above to a liquid crystal display device, problems, such as the contrast ratio of a liquid crystal display screen, fall easily.

The present invention provides a plastic substrate which can improve the electrical conductivity and can serve as an auxiliary electrode by itself.

One embodiment of the present invention to provide a plastic substrate that can improve the electrical conductivity and can serve as an auxiliary electrode itself, but does not inhibit the transmittance of light incident from the rear surface.

In one embodiment of the present invention to provide a plastic substrate including a metal film but no cracking when bending.

In one embodiment of the present invention to provide a transparent electrode film with improved electrical conductivity while protecting the electrode from the outside.

The present invention also prevents the dimensional change of the film due to the high temperature generated in the deposition process of the existing transparent electrode ITO by introducing a protective layer or an electrode layer by coating and curing the organic protective layer containing a conductive material on the metal film. To provide a plastic substrate that can be.

An object of the present invention is to provide an electronic paper display device and a liquid crystal display device using a plastic substrate having a high contrast sharp image quality using high light transmittance.

Another object of the present invention is to provide an electronic paper, a liquid crystal display device, and an organic light emitting device that are lightened by including the plastic substrate as the lower substrate.

In one embodiment of the present invention, a plastic film; Reflective and / or electrically conductive metal films; And a resin layer in which a conductive material is dispersed.

In the plastic substrate according to the embodiment of the present invention, the metal film is a single layer selected from aluminum, titanium, silver, platinum, magnesium, tungsten, palladium and alloys thereof, indium tin oxide (ITO), and indium zinc oxide (IZO). Or a multilayer reflective metal film. In the plastic substrate according to a preferred embodiment, the reflective metal film may be selected from aluminum, magnesium, and alloys thereof. In another embodiment, the reflective metal film may include a lower metal film selected from aluminum, magnesium, and an alloy thereof; It may be an upper metal film of indium tin oxide or indium zinc oxide.

In the plastic substrate according to the embodiment of the present invention, the reflective metal film may have a thickness of 10 to 1,000 nm, and preferably, a thickness of 50 to 300 nm.

In the plastic substrate according to another embodiment of the present invention, the metal film may be selected from magnesium, barium, gold, aluminum, titanium, silver, platinum, tantalum and palladium alone, alloys or oxides thereof; It may be an electrically conductive metal film selected from indium tin oxide and indium zinc oxide.

In the plastic substrate according to the exemplary embodiment of the present invention, the electrically conductive metal film may be indium tin oxide or indium zinc oxide.

In a specific embodiment, the electroconductive metal film may be one selected from magnesium, barium and gold, or an oxide thereof, and in another example, the electroconductive metal film may be indium tin oxide.

In the plastic substrate according to the embodiment of the present invention, the electrically conductive metal film may have a thickness of 1 to 300 nm.

In the plastic substrate according to the embodiment of the present invention, the electrically conductive metal film may have a thickness of 1 to 100 nm. Specifically, the electrically conductive metal film may have a thickness of 1 to 50 nm.

In the plastic substrate according to the embodiment of the present invention, the metal film may be a gas barrier film or a moisture barrier film.

In the plastic substrate according to an embodiment of the present invention, the plastic film may be a polyimide film.

In the plastic substrate according to the embodiment of the present invention, the plastic film has an average linear expansion coefficient (CTE) of 50.0 ppm / ° C. or less measured in a range of 50 to 250 ° C. by thermomechanical analysis based on a film thickness of 50 to 100 μm. It may be a polyimide film having a yellowness of 15 or less.

In the plastic substrate according to the embodiment of the present invention, the plastic film has an L value of 90 or more, a value of 5 or less, and b value of the color coordinate measured by a UV spectrophotometer based on a film thickness of 50 to 100 μm. It may be a polyimide film of 5 or less.

The plastic substrate according to the embodiment of the present invention may further include a protective layer formed on the metal film. In this case, the protective layer may be a polyimide layer having an average linear expansion coefficient (CTE) of 50.0 ppm / ° C. or less and a yellowness of 15 or less, measured in the range of 50 to 250 ° C. by thermomechanical analysis based on a thickness of 50 to 100 μm. In addition, the protective layer may be a polyimide layer having an average transmittance of 85% or more at 380 to 780 nm when the transmittance is measured by a UV spectrophotometer based on a thickness of 50 ~ 100㎛. As another example, the protective layer may be a polyimide layer having a transmittance of 88% or more at 550 nm and a transmittance of 70% or more at 420 nm when the transmittance is measured by a UV spectrophotometer based on a thickness of 50 to 100 μm.

In the plastic substrate according to the embodiment of the present invention, the conductive material may be carbon nanotubes or indium-tin oxide powder.

In the plastic substrate according to the embodiment of the present invention, the resin layer in which the conductive material is dispersed may be formed from a polyimide varnish in which the conductive material is dispersed.

In a specific embodiment, the resin layer in which the conductive material is dispersed may be formed from a polyimide varnish containing 0.001 to 1 parts by weight of carbon nanotubes based on 100 parts by weight of the polyimide resin solid content.

In a specific embodiment, the resin layer in which the conductive material is dispersed may be formed from a polyimide varnish containing 2 to 100 parts by weight of indium tin oxide powder based on 100 parts by weight of the polyimide resin solid content.

In this case, the indium-tin oxide powder may contain 80 to 95% by weight of indium oxide and 5 to 20% by weight of tin oxide.

In the plastic substrate according to the embodiment of the present invention, the resin layer in which the conductive material is dispersed may have a thickness of 10 nm to 25 μm.

Plastic substrate according to another embodiment of the present invention may be to include a chemical resistant layer on at least one side of the plastic film. In this case, the chemical resistant layer may be at least one resin layer selected from acrylic resin, epoxy resin, polysilazane and polyimide resin.

Plastic substrate according to another embodiment of the present invention may be to include an inorganic layer, which is formed on the lower portion of the plastic film or the lower portion of the metal film.

In this case, the inorganic layer may be a single layer or a multilayer including at least one inorganic material selected from SiNx, AlxOy, and SiOx.

The plastic substrate according to another embodiment of the present invention may include a metal oxide layer formed on the upper or lower surface of the resin layer in which the conductive material is dispersed.

In this case, the metal oxide layer may be a layer made of AgO.

The plastic substrate according to one embodiment of the present invention may have a light transmittance of 50% or more at 500 nm wavelength. In addition, the surface resistance is 2.5 × 10 ⁶ Ω / sq. It may be the following.

In another embodiment of the present invention, a plastic film; An indium tin oxide or indium zinc oxide thin film formed on a plastic film and having a predetermined pattern; And a resin layer in which a conductive material is dispersed, which is formed on an indium tin oxide or an indium zinc oxide thin film. In this case, the conductive material may be carbon nanotube or indium-tin oxide powder.

In one embodiment of the present invention, the transparent electrode film may have a light transmittance of 50% or more at a wavelength of 500 nm.

In one embodiment of the present invention, the transparent electrode film has a surface resistance of 700Ω / sq. It may be below.

An exemplary embodiment of the present invention provides a transmissive electronic paper device including a plastic substrate according to the embodiments as a lower substrate.

Another exemplary embodiment of the present invention provides a display device device including the plastic substrate according to the embodiments as a lower substrate.

Another exemplary embodiment of the present invention provides an organic light emitting device including the plastic substrate according to the embodiments as a lower substrate.

The plastic substrate according to the embodiment of the present invention is a substrate having improved electrical conductivity, no inhibition of transmittance, and no cracking of the film due to the metal film.

In addition, the plastic substrate according to the embodiment of the present invention is provided with a reflective metal film, and when applied in the form of an internal reflection material, for example, light incident from the outside of the liquid crystal display device is diffusely reflected from the metal film formed on the plastic film. Since the reflected light does not penetrate the plastic film, parallax is hardly generated, and a clear image without image blurring can be obtained, and the metal film can block not only external air or moisture but also air or moisture contained in the film itself. In particular, since it is not necessary to form a gas barrier layer on the side of the liquid crystal layer side of the plastic film, the cost can be further reduced and the yield can be improved.

The plastic substrate according to one embodiment of the present invention is useful as a lower substrate in an electronic paper display device, a liquid crystal display device, and the like, and as a lower substrate, the plastic substrate can reduce the weight of the display device.

Hereinafter, the present invention will be described in more detail.

The present invention relates to a plastic substrate used for an electronic paper display device, a display device, and the like, and, according to an embodiment, relates to a plastic substrate capable of performing a transmission function and an electrode function in a transmission type electronic paper display device and a display device.

2 shows an example of a plastic substrate according to an embodiment of the present invention, referring to the plastic film 100; A metal film 110 disposed on the plastic film and having a conductive function, and a resin layer 120 on which a conductive material formed on the surface of the metal film is dispersed. In the case of the plastic substrate according to another embodiment, which will be described later, the metal film 110 having a conductive function may be a reflective metal film or a conductive and reflective metal film.

In a subsequent process such as a case where a metal film is formed directly on the plastic film 100 by vapor deposition or a process (TFT ARRAY) of raising a thin film transistor (TFT) on the film, Can cause expansion and contraction. As a result, the plastic film constituting the plastic substrate may be limited due to limited process conditions, misalignment with subsequent layers or members, or failure to maintain horizontal (flattening) film. 100) is advantageous as the glass transition temperature is 250 ° C. or higher and the coefficient of linear expansion is small. Specifically, the average linear expansion measured in the range of 50 to 250 ° C. by the Thermomechanical Analyzer based on the film thickness of 50 to 100 μm. It may be advantageous that the coefficient (CTE) is a high heat resistant film having 50.0 ppm / ° C. or less, preferably 35.0 ppm / ° C. or less. Examples thereof include, but are not limited to, polyimide films.

In view of transparency, a colorless transparent plastic film, specifically a polyimide film having a yellow degree of 15 or less based on a film thickness of 50 to 100 mu m, may be preferable. Also, a polyimide film having an average transmittance of 85% or more at 380 to 780 nm can be used as a plastic film when the transmittance is measured using a UV spectrophotometer based on a film thickness of 50 to 100 μm. When such transparency is satisfied, it can be used as a transparent electronic paper and a plastic substrate for a liquid crystal display device. Moreover, the plastic film may be a polyimide film having a transmittance of at least 88% at 550 nm and a transmittance of at least 70% at 420 nm when the transmittance is measured by a UV spectrophotometer based on a film thickness of 50 to 100 μm.

The polyimide film has an L value of 90 or more, a value of 5 or less and a b value of 5 or less when a color coordinate is measured by a UV spectrophotometer based on a film thickness of 50 to 100 占 퐉 in terms of improving transparency and enhancing permeability. Lt; / RTI > or less.

Such a polyimide film may be obtained by polymerizing an aromatic dianhydride and a diamine to obtain a polyamic acid, and then imidating it. Examples of the aromatic dianhydride include 2,2-bis (3,4-dicarboxy). Phenyl) hexafluoropropane dianhydride (6-FDA), 4- (2,5-dioxotetrahydrofuran-3-yl) -1,2,3,4-tetrahydro or phthalene-1,2 Dicarboxylic anhydride (TDA), 4,4 ′-(4,4′-isopropylidenediphenoxy) bis (phthalic anhydride) (HBDA), pyromellitic dianhydride (PMDA) ), Biphenyltetracarboxylic dianhydride (BPDA) and oxydiphthalic dianhydride (ODPA), but is not limited thereto.

Examples of the aromatic diamine include 2,2-bis [4- (4-aminophenoxy) -phenyl] propane (6HMDA), 2,2'-bis (trifluoromethyl) -4,4'- Biphenyl (2,2'-TFDB), 3,3'-bis (trifluoromethyl) -4,4'-diaminobiphenyl (3,3'-TFDB), 4,4'-bis (3-aminophenoxy) diphenyl sulfone (DBSDA), bis (3-aminophenyl) sulfone (3DDS), bis (APB-133), 1,4-bis (4-aminophenoxy) benzene (APB-134), 2,2'-bis [3- (3-aminophenoxy) phenyl] hexafluoropropane ), Hexafluoropropane (4-BDAF), 2,2'-bis (3-aminophenyl) hexafluoropropane (3,3 ' But not limited to, at least one selected from the group consisting of 2,2'-bis (4-aminophenyl) hexafluoropropane (4,4'-6F) .

* There is no particular limitation in the method for producing a polyimide film by using such a monomer, and for example, the aromatic diamine and the aromatic dianhydride are polymerized under a first solvent to obtain a polyamic acid solution. After imidating the polyamic acid solution, the imidized solution was added to the second solvent, filtered and dried to obtain a solid content of the polyimide resin, and the polyimide solution obtained by dissolving the obtained polyimide resin solid content in the first solvent was prepared. It can form into a film through a film forming process. In this case, the second solvent may have a lower polarity than the first solvent. Specifically, the first solvent may include m-crossover, N-methyl-2-pyrrolidone (NMP), dimethylformamide (DMF) Amide (DMAc), dimethylsulfoxide (DMSO), acetone, and diethyl acetate, and the second solvent may be at least one selected from water, alcohols, ethers and ketones.

On the other hand, in order to form a metal film on the plastic film, the surface smoothness of the plastic film may be 2 탆 or less, preferably 0.001 to 0.04 탆, in order to form a metal film of uniform thickness.

A metal film 110 (hereinafter, referred to as a "conductive metal film") having conductivity is formed on such a plastic film. When the permeability is taken into account, the thickness of the conductive metal film is 1 to 300 nm, In particular, when the thickness of the conductive metal film is 1 to 100 nm, it is advantageous to lower the coefficient of linear expansion of the plastic film substrate without deterioration of the optical characteristics such as the transmittance due to the metal film. If the thickness of the conductive metal film is thicker than this, the conductivity is increased but the plastic film may be cracked during the bending.

In this case, the conductive metal film may be selected from magnesium, barium, gold, aluminum, titanium, silver, platinum, tantalum, and palladium alone, alloys or oxides thereof, or indium-tin oxide (ITO, Indium-Tin-Oxide) or indium-zinc. An oxide (IZO, Indium-Zinc-Oxide) may be mentioned, but is not limited thereto. In the case of a metal or an alloy of metal, the influence of the transmittance by thickness may be greater than in the case of a metal oxide. Therefore, in the case of an alloy of a metal or a metal, the thickness of the metal film may be 1 to 50 nm.

When such a conductive metal film is included, the electrical conductivity can be improved without hindering the permeability, and further, the conductive metal film can function as an electrode. Particularly in this respect, the conductive metal film may be an ITO or IZO thin film.

Such a conductive metal film is also advantageous from the viewpoint of electrical conductivity and exhibits gas barrier properties and / or moisture barrier properties, and can also function to inhibit the plastic film from being deformed by gas or moisture.

The conductive metal film may be formed on the plastic film by sputtering, ion deposition, electroplating or chemical vapor deposition, and the present invention is not limited thereto.

According to one embodiment of the present invention, since the high heat-resistant film is used as the plastic film, the process conditions for forming the conductive metal film are almost unlimited as compared with the conventional plastic substrate.

The plastic substrate according to an embodiment of the present invention further includes a resin layer 120 on which a conductive material is dispersed, specifically, a resin layer in which carbon nanotubes or ITO powder are dispersed, on the conductive metal film 110 , A resin layer in which carbon nanotubes or ITO powder is dispersed can further improve the conductivity and function as an additional electrode layer. The resin layer in which the carbon nanotubes or ITO powder is dispersed may be a layer obtained by applying a transparent varnish containing carbon nanotubes or ITO powder and may be a layer formed by dispersing and applying carbon nanotubes or ITO powder to a transparent polyimide varnish have.

At this time, the carbon nanotubes in the polyimide varnish may be included in an amount of 0.001 to 1 part by weight based on 100 parts by weight of the resin solid content in the varnish in terms of the surface resistance and light transmittance of the display electrode film.

On the other hand, carbon nanotubes are not limited in their kind, and the chemical or physical treatment of single-wall carbon nanotubes (SWCNTs), double wall carbon nanotubes (DWCNTs), multiwall carbon nanotubes (MWCNTs) Modified carbon nanotubes or the like.

In addition, the method of dispersing the carbon nanotubes in the varnish is not particularly limited. For example, physical dispersion and chemical treatment such as ultrasonic dispersion, three-roll dispersion, homogenizer or Kneader, Mill-Blender, The carbon nanotubes can be dispersed in the varnish by the chemical bonding of the CNTs. In this case, the introduction of the CNT can be carried out by in-situ polymerization of the varnish or by blending after the polymerization of the varnish, And a method of using an additive such as an emulsifier or the like.

The numerical layer in which the carbon nanotubes are dispersed can be formed by a spin coating method, a casting method such as a doctor blade, and the like. However, the present invention is not limited thereto.

In particular, since the light having not been inhibited by the transmittance through the metal thin film can improve the conductivity without being significantly inhibited by the permeability due to the unique structure of the carbon nanotube, It is preferable to form it on a film.

When the ITO powder is used together with or in place of the carbon nanotubes, the content thereof may be 2 to 100 parts by weight based on 100 parts by weight of resin solids content in the varnish.

The electrical properties of ITO powders can be controlled by adjusting the content of indium-tin mixed oxide and by adjusting the content of indium oxide and tin oxide in the indium-tin mixed oxide itself. The indium-tin mixed oxide (ITO) may preferably contain 80 to 95% by weight of indium oxide (In ₂ O ₃ ) and 5 to 20% by weight of tin oxide (SnO ₂ ). The indium-tin mixed oxide may be in the form of powder, and the size thereof depends on the materials used and the reaction conditions, and preferably has an average minimum diameter of 30 to 70 nm and an average maximum diameter of 60 to 120 nm.

There is no particular limitation on the method for producing the varnish containing the indium-tin mixed oxide, but the indium-tin mixed oxide can be dispersed in the polyamic acid solution, and the indium-tin mixed oxide ( ITO) in an amount of 2 to 100 parts by weight may be advantageous in terms of conductivity and maintaining the ductility of the film.

The method of adding the indium-tin mixed oxide to the polyamic acid solution is not particularly limited, and examples thereof include a method of adding the indium-tin mixed oxide to the polyamic acid solution before or during the polymerization, a method of kneading the indium- A method in which a dispersion containing an indium-tin mixed oxide is prepared and mixed with a polyamic acid solution, and the like. At this time, the dispersion property of the indium-tin mixed oxide is influenced by the acid-basicity and viscosity of the dispersion solution and affects the conductivity and the uniformity of the transmittance of the visible light depending on the dispersion. Preferred dispersing methods include a three-roll mill, an ultrasonic dispersing machine, a homogenizer or a ball mill.

In forming the resin layer in which CNT or ITO powder is dispersed, the thickness of 10 nm to 25 mu m may be advantageous in terms of suppressing deterioration of optical characteristics such as transmittance of the display.

Since the substrate is formed of plastic, it can serve as a transparent plate and a transparent electrode substrate, so that the liquid crystal display device can be lightened.

Plastic substrate according to another embodiment of the present invention may also be able to form a metal oxide layer on the upper or lower portion of the resin layer 120 in which the conductive material is dispersed, the oxide film to improve the permeability and also to block gas and moisture It can also function as a barrier layer. As a specific example, the oxide film may be a film made of silver oxide (AgO). This is shown in Figs. 3 to 4. FIG. 3 illustrates an example of a plastic substrate having an oxide film 111 formed on a resin layer 120 on which a conductive material is dispersed. FIG. 4 illustrates an example of a plastic substrate on which an oxide film 111 are formed on a surface of a plastic substrate.

When the oxide film 111 is formed, the thickness of the oxide film 111 is not particularly limited, but may be advantageously about 10 nm to 300 nm in terms of adhesion to the resin layer, uniformity of the thickness of the oxide film, and prevention of cracking during bending of the substrate .

The plastic substrate according to another embodiment of the present invention may further include a layer for preventing penetration of the solvent into the substrate and the electrode. In the present invention, such a layer is referred to as a chemical-resistant layer.

Examples of the plastic substrate on which the chemical layer is formed are shown in FIGS. 5 to 8, and FIGS. 5 and 8 show examples in which the chemical layer 102 is formed under the plastic film 100 6 shows an example of forming the chemical-resistant layer 102 on the upper and lower portions of the plastic film 100, and FIG. 7 shows an example in which the chemical-resistant layer 102 is formed only on the upper portion of the plastic film 100 FIG.

The composition used for forming the chemical resistant layer 102 is particularly limited so long as it is a composition that satisfies conditions of good insolubility in organic solvents and good adhesion to a base film in a display manufacturing process without impairing transparency. The specific example may be a layer including at least one resin selected from an acrylate resin, an epoxy resin, a polysilazane, and a polyimide resin.

The formation of the chemical-resistant layer 102 on the lower side of the plastic film 100 can prevent the solvent penetration from the outside of the plastic film 100 and the formation of the chemical- It is possible to help form the electrically conductive metal film 110 on the plastic film 100 as well as the function of the anti-

The method of forming the chemical resistant layer 102 is not particularly limited, but for example, spin coating, casting, roll coating, or impregnation may be used.

Although the thickness of the chemical resistant layer 102 is not limited, the thickness of about 10 nm to 500 nm may be advantageous in terms of not impairing optical properties such as thickness uniformity and transmittance.

The plastic substrate according to another embodiment of the present invention may further form a protective layer (flattening layer) after forming a metal film, an example of which is illustrated in FIG. 8. The protective layer 103 serves to protect the reflective metal film and to smooth the surface of the reflective metal film, and subsequently facilitates the formation of the resin layer 120 in which the conductive material is dispersed, and prevents occurrence of warping of the plastic substrate. It may be advantageous in terms of what it can do. In this respect, the protective layer may be advantageously provided with insulation without inhibiting the transmission of light reflected through the reflective metal film.

In this regard, a protective layer can be formed of a polyimide resin layer such as a polyimide film exemplified as a plastic film. For example, the protective layer is advantageously a colorless transparent resin layer having a visible light transmittance of 85% or more.

The thickness of the protective layer 103 may be sufficient to planarize the uneven surface due to the reflective metal film 110, and the thickness of the protective layer 103 is not limited, but considering the adhesive strength with the metal film layer and the ease of deposition of the organic light emitting layer. 10 nm to about 500 nm.

The plastic substrate according to another embodiment of the present invention may have an inorganic layer. The plastic substrate is made of the plastic film 100 as a substrate, and since the film itself contains air or moisture, and the air permeability and moisture permeability are high, air or moisture is transferred from the outside air or the film itself to the liquid crystal layer or the organic light emitting element layer. There is a possibility that bubbles may be generated by intrusion, or the liquid crystal and the organic light emitting element may be oxidized by moisture and oxygen, resulting in deterioration and deterioration of the lifespan of the display device. For this purpose, a single layer or multilayer inorganic layer may be formed on the inner or outer surface of the plastic substrate to serve as a barrier layer for blocking gas and moisture. That is, not only the air or moisture which flows in from the outside but also the air or moisture contained in the film itself can be interrupted | blocked.

An example of this is shown in Figs. 9 to 10.

FIG. 9 shows an example in which the inorganic layer 101 is formed on the lower part of the plastic film 100. FIG. 10 shows an example in which the inorganic film 101 is formed on the lower side of the plastic film 100 and the lower surface of the resin layer 120 in which the conductive material is dispersed. And the inorganic layer 101 is formed.

Of course, the conductive metal layer 110, the oxide layer 111, etc. may also be useful as a moisture and gas barrier layer without the inorganic layer as described above, but the inorganic material as an embodiment for providing more sufficient moisture and gas barrier properties. The layer 101 may be further provided.

SiOx, SiNx, AlxOy-based oxides and the like may be used for the formation of the inorganic layer 101. Although the formation method is not limited, generally known inorganic vapor deposition methods such as low temperature film formation method, high temperature film formation method and PECVD may be used. It is available. Although the thickness of the inorganic layer 101 is not limited thereto, the thickness of the inorganic layer 101 may be about 10 nm to 300 nm in consideration of the ease of deposition of the organic light emitting layer and the low permeability of gas and moisture to prevent oxidation of the metal layer, the organic layer, and the liquid crystal layer. . It is also possible to form two to four layers of multilayers together with the planarization layer.

The plastic substrate according to the embodiments of the present invention thus obtained is useful as a substrate in electronic paper display devices and display device devices, and when used as a lower substrate, the electrical conductivity is improved without impairing the transmittance of light incident from the rear surface. A bright image can be realized.

In addition, in the case of a plastic substrate, in order to form a conductive metal film and use it as an electrode, the thickness of the conductive metal film deposited on the plastic film becomes thick, which causes peeling and metal layers due to a difference in flexibility between the plastic substrate and the metal layer when the plastic substrate is bent. This can cause cracks, which can lead to loss of electrode function. However, in the case of the plastic substrate according to an embodiment of the present invention, the thickness of the conductive metal film can be made thinner by introducing the resin layer in which the conductive material is dispersed together with the conductive metal film, and the conductive metal film and the conductive It is possible to reduce the problems of peeling and cracking of the conductive metal film due to the difference in dimensional stability caused by bending due to the resin of the resin layer in which the conductive material rising on the metal film is dispersed, And the peeling resistance and the uniformity against bending of the substrate can be improved.

The plastic substrate according to one embodiment of the present invention preferably has a surface resistance of 2.5 x 10 ⁶ Ω / sq. Or less, and the light transmittance at a wavelength of 500 nm is 50% or more.

An example of a liquid crystal display device of a flat panel display device in which a plastic substrate according to an embodiment of the present invention is applied as a lower substrate is shown in Fig. 11 and an example in which the same is applied to a substrate of an organic EL device is shown in Figs. 12 to 13 But is not limited thereto. In particular, Fig. 13 shows a transmissive organic EL device.

On the other hand, such a plastic substrate may be useful as a transparent electrode film. In this case, the conductive metal film may be an ITO or IZO thin film.

In fabricating the organic EL device, an electrode layer is formed of a conductive metal film containing Ag, Mg, Ba or Ca, the transparent electrode containing Ag is used as an anode, and the transparent electrode containing Ca or Mg is used as a cathode It is possible.

An example of the cross section of the transparent electrode is that the conductive metal film 110 in the plastic substrate shown in Fig. 2 is formed into a stripe shape by photolithography and etching, and a conductive material is dispersed on the stripe- Except that a resin layer 120 is formed.

In the case of a transparent electrode film, a conductive metal film 110 is formed on a plastic film, and then the conductive metal film is patterned by photolithography and etching to form a stripe-shaped metal film. The stripe-shaped metal film thus formed serves as a transparent electrode. The resin layer in which the conductive material is dispersed on the ITO transparent electrode is formed on the formed metal electrode by the above-described method. Subsequently, when heated and cured, a transparent electrode film can be obtained.

The transparent electrode film thus obtained can improve the electrical conductivity without impairing the transmittance of the incident light, thereby realizing a bright image. In particular, the transparent electrode film exhibits a higher light transmittance than an electrode film composed of only carbon nanotubes, It is advantageous from the side.

The transparent electrode film according to an embodiment of the present invention may have a surface resistance of 700? / Sq. Or less, and the light transmittance at a wavelength of 500 nm is 50% or more.

The plastic substrate according to another embodiment of the present invention may have the structure shown in FIG. 2, but may replace the electrically conductive metal film with the reflective metal film 110.

In consideration of reflectivity, the metal film is advantageously formed into a thick film, and preferably, the metal film has a thickness of 10 to 1000 nm.

In order to improve the transmittance as compared to the reflective function, for example, when used in the transmission type electronic paper and the liquid crystal display device, the metal film is advantageously formed into a thin film. Preferably, the metal film is about 50 to 300 nm. There is no deterioration in optical properties such as transmittance, and there is an advantage of lowering the coefficient of linear expansion due to the metal film deposited on the surface of the plastic film substrate.

If the thickness of the metal film is too thick, the reflectivity or conductivity is increased, but there is a risk of cracking when bending the plastic film.

In this case, the metal film may be made of aluminum, titanium, silver, platinum, magnesium , tantalum and palladium alone or an alloy thereof, or a film including ITO (Indium-Tin-Oxide) or IZO (Indium-Zinc-Oxide). It can be.

In the case of including such a reflective metal film, the electrical conductivity can be improved without hindering transmittance, and the reflective metal film can function as an electrode. In this regard, the reflective metal film may include an ITO or IZO thin film on top of the reflective metal film made of aluminum or an alloy thereof, or magnesium or an alloy thereof.

Such a reflective metal film is advantageous in terms of electrical conductivity, and may also perform a function of suppressing deformation of the plastic film by gas or moisture by expressing gas barrier properties and / or moisture barrier properties.

Formation of the reflective metal film on the plastic film may use sputtering, ion deposition, electroplating, or chemical vapor deposition, and the like, but is not particularly limited thereto.

According to one embodiment of the present invention, since the high heat resistant film is used as the plastic film as described above, the process conditions for forming the reflective metal film are hardly limited as compared with the conventional plastic substrate.

When the reflective metal film is formed on the plastic film as described above, when it is applied in the form of an internal reflection reflector, light incident from the outside of the liquid crystal display device is diffusely reflected on the metal film formed on the plastic film, Since light does not penetrate the plastic film, parallax is hardly produced, and a clear image without image blur can be obtained.

Formation of the metal film on the plastic film may use sputtering, ion deposition, electroplating, or chemical vapor deposition as described above, but is not particularly limited thereto.

Plastic substrates according to an embodiment of the present invention including a reflective metal film may also include a metal oxide film layer, a chemical resistant layer, an inorganic material layer, and the like, as described above.

The plastic substrate including the reflective metal film according to the embodiment of the present invention thus obtained is useful as a substrate in electronic paper display devices and flat panel display devices, and when used as a lower substrate without a reflective metal film, The electrical conductivity is improved without impairing the transmittance, so that a bright image can be realized in the transmissive display.

As such, since the substrate is made of plastic, the substrate may serve as a reflector and a transparent electrode substrate, thereby reducing the weight of the liquid crystal display.

The plastic substrate including the reflective metal film according to the embodiment of the present invention is useful as a lower substrate such as a reflective electronic paper and a liquid crystal display device that implements an image by reflecting light from the outside without having an internal light source.

If the metal film is to be patterned, it is also useful as a semi-transparent electronic paper and a lower substrate such as a liquid crystal display device. For example, a metal film made of a reflective material forms a pattern at a portion corresponding to the periphery of the pixel portion of the transparent electrode. In the center of the pixel portion, for example, the portion where the metal film is removed is smaller than the area of the pixel portion, for example, in a state where the position of the pixel portion is approximately 10-20%).

In this way, the plastic substrate may be used in the transflective liquid crystal display device by adding a pattern process. In other words, when the backlight is used as the light source, the image can be displayed by transmitting light through a portion of the reflector corresponding to the pixel portion where no metal film exists. In addition, when external light is used as the light source, the external light is reflected at the portion where the metal film exists among the reflector portions corresponding to the pixel portion to display an image.

In addition, in the case of a plastic substrate, in order to form a reflective metal film and use it as an electrode, the thickness of the reflective metal film deposited on the plastic film becomes thick, which causes peeling and metal layers due to a difference in flexibility between the plastic substrate and the metal layer when the plastic substrate is bent. This can cause cracks, which can lead to loss of electrode function. However, in the case of the plastic substrate according to the embodiment of the present invention, the thickness of the reflective metal film may be reduced by introducing a resin layer in which a conductive material is dispersed along with the reflective metal film, and the reflective metal film and the reflective film on the plastic film and the film Since the resin of the resin layer in which the conductive material on the metal film is dispersed can reduce the problem of peeling and cracking of the reflective metal film due to the difference in the dimensional stability generated when bending, the display of the reflective metal film as compared to the single electrode layer of the conventional reflective metal film. And peeling resistance and uniformity against bending of the substrate can be improved.

On the other hand, the method for producing a plastic substrate comprising a plastic film, a metal film, a protective layer and a transparent electrode layer according to the present invention is not particularly limited, the process of preparing a polyimide precursor solution of a plastic film as an example ; Preparing a solution containing a partially cured intermediate by at least partly ring closing, condensing, crosslinking or polymerizing a portion of the precursor in the precursor solution; Preparing a coating liquid based on a solution containing a partially cured intermediate; Applying a coating liquid onto the workpiece; Obtaining a plastic film by heating and completely curing the coating liquid; And forming a protective layer (planarization layer) for planarizing the surface of the metal film using the above resin. And forming a resin layer including a conductive material on the surface of the metal film to form a transparent electrode layer.

EXAMPLES Hereinafter, the present invention will be described in detail with reference to the following examples. However, the present invention is not limited to these examples.

≪ Production of plastic film &

Production Example 1

First, a mixture of 2,2'-bis (trifluoromethyl) -4,4'-diaminobiphenyl (2,2'-TFDB), biphenyltetracarboxylic dianhydride (BPDA) -Bis (3,4-dicarboxyphenyl) hexafluoropropanediamine hydrate (6-FDA) was condensed in dimethylacetamide by a known method to obtain a polyimide precursor solution (solid content 20%). This reaction process is shown in Scheme 1 below.

(Scheme 1)

Subsequently, 300 g of this polyimide precursor solution was added with 2 to 4 equivalents of acetic anhydride (Acet oxide) and pyridine (Pyridine) as a chemical curing agent, according to a known process. After heating the polyamic acid solution at a temperature in the range of 20 to 180 ° C. at a rate of 1 to 10 ° C./min for 2 to 10 hours, the polyamic acid solution was partially imidized and cured by partially imidizing (partially curing). Korean) A solution containing an intermediate was prepared.

The following Reaction Scheme 2 shows a process of obtaining a polyimide film by heating a polyimide precursor. In the embodiment of the present invention, the precursor solution is not completely imidized to form a polyimide, but only a predetermined proportion of the precursor is imidized I would like to use one.

(Scheme 2)

More specifically, the polyimide precursor solution is heated and stirred under predetermined conditions to dehydrate and close the ring between the hydrogen atom and the carboxyl group of the amide group of the polyimide precursor, as shown in the following formula (1). Similarly, the form B of the intermediate portion and the form C of the imide portion are generated by the reaction. Also, in the molecular chain, a form A (polyimide precursor part) in which dehydration does not occur completely exists.

That is, the molecular chain in which the polyimide precursor is partially imidized has a structure of a form A (polyimide precursor), a form B (intermediate part) and a form C (imide part) as shown in the following chemical formula 1 .

Therefore, 30 g of the imidized solution containing the above structures is put into 300 g of water and precipitated. The precipitated solids are filtered and pulverized to fine powder, dried in a vacuum drying oven at 80 to 100 ° C for 2 to 6 hours To obtain about 8 g of resin solid powder. The polyimide precursor part of the [Form A] was converted into [Form B] or [Form C] by passing through the above steps. The resin solid content was dissolved in 32 g of DMAc or DMF as a polymerization solvent to prepare a 20 wt% polyimide solution . This was heated for 2 to 8 hours while raising the temperature at a rate of 1 to 10 ° C./min in a temperature range of 40 to 400 ° C. to obtain a polyimide film having a thickness of 50 μm and a thickness of 100 μm.

When the polyimide precursor partially imidated, the reaction scheme is shown in Scheme 3.

(Scheme 3)

For example, under the above conditions, about 45 to 50% of the precursor is imidized and cured. The imidization rate at which a part of the precursor is imidized can be easily controlled by changing the heating temperature, time, etc., and is preferably about 30 to 90%.

In the step of imidizing a part of the polyimide precursor, water is generated when the polyimide precursor is dehydrated and cyclized and imidized, and this water causes hydrolysis of the amide of the polyimide precursor and cleavage of the molecular chain There is a fear that the stability may be lowered. Therefore, when the polyimide precursor solution is heated, an azeotropic reaction using toluene, xylene, or the like is added or removed by volatilization of the dehydrating agent mentioned above.

Next, an example of a step of manufacturing a coating liquid will be described. First, a uniform coating liquid is prepared in the ratio of 100 weight part of solutions and 20-30 weight part of polyimide precursors to the solvent which used the partially hardened intermediate at the time of manufacture of a polyimide precursor.

Subsequently, the resin solution was cast on a coated film for film forming such as glass or SUS using spin coating or a doctor blade, and then a film having a thickness of 50 μm was formed through the above-mentioned high temperature drying process. At this time, the formed film was formed with the same refractive index on the entire surface of the film because only one side was not stretched based on the vertical / horizontal axis of the film.

Production Example 2

N, N-dimethylacetamide (DMAc) (34.1904 g) was charged into a 100 ml 3-neck round bottom flask equipped with a stirrer, a nitrogen inlet, a dropping funnel, a temperature controller and a condenser, After lowering the temperature to 0 占 폚, 4.1051 g (0.01 mol) of 6-HMDA was dissolved and the solution was maintained at 0 占 폚. To this, 4.4425 g (0.01 mol) of 6-FDA was added and stirred for 1 hour to completely dissolve 6-FDA. At this time, the solid content was 20 wt%, and then the solution was left at room temperature and stirred for 8 hours. At this time, a polyamic acid solution having a solution viscosity of 2400 cps at 23 占 폚 was obtained.

After completion of the reaction, the polyamic acid solution obtained was cast to a thickness of 500㎛ ~ 1000㎛ by using a doctor blade on a glass plate and dried in a vacuum oven for 1 hour at 40 ℃, 2 hours at 60 ℃ to obtain a self standing film A polyimide film having a thickness of 50 μm was obtained by heating at 80 ° C. for 3 hours at 100 ° C., 1 hour at 100 ° C., 1 hour at 200 ° C., and 30 minutes at 300 ° C. in a high temperature furnace oven.

Production Example 3

In Preparation Example 2, 2.87357 g (0.007 mol) of 6-HMDA was dissolved in 32.2438 g of N, N-dimethylacetamide (DMAc) and 0.7449 g (0.003 mol) of 4-DDS was added thereto. 4.4425 g (0.01 mol) was added and stirred for 1 hour to completely dissolve 6-FDA. At this time, the solid content was 20 wt%, and then the solution was left at room temperature and stirred for 8 hours. At this time, a polyamic acid solution having a solution viscosity of 2300 cps at 23 ° C was obtained.

Then, a polyimide film was produced in the same manner as in Production Example 2 above.

Production Example 4

4.1051 g (0.01 mol) of 6-HMDA was dissolved in 32.4623 g of N, N-dimethylacetamide (DMAc) in Production Example 2 and 3.1097 g (0.007 mol) of 6-FDA was added thereto. mol) were added and stirred for 1 hour to completely dissolve 6-FDA and TDA. At this time, the solid content was 20 wt%, and then the solution was left at room temperature and stirred for 8 hours. At this time, a polyamic acid solution having a solution viscosity of 2200 cps at 23 占 폚 was obtained.

Then, a polyimide film was produced in the same manner as in Production Example 2 above.

Production Example 5

In Preparation Example 2, 2.9233 g (0.01 mol) of APB-133 was dissolved in 29.4632 g of N, N-dimethylacetamide (DMAc), and 4.4425 g (0.01 mol) of 6-FDA was added thereto, followed by stirring for 1 hour. 6-FDA was completely dissolved. At this time, the solid content was 20 wt%, and then the solution was left at room temperature and stirred for 8 hours. At this time, a polyamic acid solution having a solution viscosity of 1200 cps at 23 占 폚 was obtained.

Then, a polyimide film was produced in the same manner as in Production Example 2 above.

The physical properties of the polyimide films obtained in Production Examples 1 to 5 were measured as follows and shown in Table 1 below.

(1) Transmission and color coordinates

The visible light transmittance of the prepared film was measured using a UV spectrometer (Varian, Cary100).

The color coordinates of the prepared film were measured according to the ASTM E 1347-06 standard by using a UV spectrometer (Varian, Cary100), and the illuminant was measured based on the measured value by CIE D65.

(2) Yellowness

Yellowness was measured according to ASTM E313 standard.

(3) Coefficient of linear expansion (CTE)

TMA (TA Instrument, Inc., Q400) was used to measure the average coefficient of linear expansion at 50-250 ° C. according to TMA-Method.

division thickness
(탆) Coefficient of linear expansion
(ppm / DEG C) Yellowness Permeability Color coordinates 380 nm
~ 780 nm 551 nm
~ 780 nm 550 nm 500 nm 420 nm L a b Manufacturing example One 50 21.6 2.46 86.9 90.5 89.8 89.3 84.6 96.22 -0.27 1.03 2 50 46 1.59 87.6 90.0 89.7 89.2 85.4 95.85 -0.12 0.99 3 50 35 2.76 87.9 89.6 89.5 89.0 58.6 95.61 -0.42 1.91 4 50 40 3.45 88.2 90.0 89.8 89.3 60.1 95.56 -0.49 2.05 5 50 46.0 6.46 83.8 88.8 87.2 84.8 73.2 94.6 0.59 5.09

Examples 1 to 10 and Comparative Examples 1 to 7 (Example of Production of Plastic Substrate)

A conductive metal film was deposited on each of the plastic films (thickness 50 탆) obtained from Production Examples 1 to 5 to form a conductive metal film. Carbon nanotubes (SWNT, CNI) were immersed in a transparent polyimide resin solid content of 100 wt% Polyimide varnish dispersed in an amount of 0.001 to 1 part by weight per 100 parts by weight of the polyimide varnish (wherein the polyimide composition is obtained by using the polyamic acid composition obtained from Preparation Examples 1 to 5) is applied as a thin film by casting or spraying, Thereby forming a dispersed resin layer. In another embodiment of the invention to form a resin layer by further mixing and dispersing 5 to 25 parts by weight of ITO powder with respect to 100 parts by weight of the polyimide resin solid content in forming the resin layer in which the CNT prepared above is dispersed (execution) Examples 9-10).

The type and thickness of the specific metal film layer and the carbon nanotube or ITO powder content and thickness in the resin layer in which carbon nanotubes or ITO powder are dispersed are shown in Table 2 below.

Plastic film Conductive metal film Dispersion of conductive material
Resin layer Kinds thickness
(nm) thickness
(um) CNT content *
ITO powder
content* Example 1 Production Example 1 Mg 10 0.4 0.01 - Example 2 Production Example 2 Mg 10 1.2 0.01 - Example 3 Production Example 1 Mg 10 2.5 0.01 - Example 4 Production Example 5 Mg 50 2.5 0.01 - Example 5 Production Example 1 Al 10 0.4 0.01 - Example 6 Production Example 2 Al 10 1.2 0.01 - Example 7 Production Example 1 Al 10 2.5 0.01 - Example 8 Production Example 5 Al 50 2.5 0.01 - Example 9 Production Example 1 Al 10 2.5 0.01 5 Example 10 Production Example 1 Al 50 2.5 0.01 25 Comparative Example 1 Production Example 1 - - - - - Comparative Example 2 Production Example 1 - - 0.04 0.001 - Comparative Example 3 Production Example 4 - - 0.2 0.03 - Comparative Example 4 Production Example 4 - - 0.2 0.05 - Comparative Example 5 Production Example 1 - - 0.4 0.01 - Comparative Example 6 Production Example 1 - - 1.2 0.01 - Comparative Example 7 Production Example 2 - - 25 0.01 - (week)
* Expressed as parts by weight based on 100 parts by weight of the polyamic acid solid content in the varnish

Experimental Example 1

The plastic substrates obtained from Examples 1 to 10 and Comparative Examples 1 to 7 were evaluated as follows, and the results are shown in Table 3.

(1) Optical characteristics

The visible light transmittance of the prepared plastic substrate was measured using a UV spectrometer (Varian, Cary100).

From the results shown in the following Table 3, the comparative example shows a drastic reduction in the permeability when the CNT content is increased to reduce the surface resistance. As a result, it can be seen that the surface resistance required by the display can not be achieved for an electrode using only CNTs.

Accordingly, when the CNT transparent electrode is formed on the conductive metal film according to the embodiment of the present invention, the required amount of CNT is reduced compared with the conventional CNT electrode, so that the CNT transparent electrode has a low surface resistance and a high light transmittance of 70% It can be used as a transparent electrode for a display.

Also, in the case of a transparent electrode using only CNTs, a significant difference in resistance on the surface of the electrode depends on the degree of dispersion of the CNTs, which may cause difficulties in manufacturing process including dispersion. On the other hand, A certain electrode function can be performed basically due to the metal layer, which can reduce the possibility of image non-implementation due to the loss of the electrode function in the display production.

(2) surface resistance

The surface resistance was measured using a high resistance meter (Hiresta-UP MCT-HT450 (Mitsuibishi Chemical Corporation), measuring range: 10 × 10 ⁵ to 10 × 10 ¹⁵ ) and a low resistance meter (CMT-SR 2000N - Point Probe System, measurement range: 10 × 10 ^-3 to 10 × 10 ⁵ ).

From the results shown in the following Table 3, the transparent electrode according to an embodiment of the present invention has a lower surface resistance than the transparent electrodes having only the CNT layer (Comparative Examples 5 to 7) based on the same amount of CNTs It is possible to know. Therefore, it can be understood that a transparent electrode having excellent transparency compared to a transparent electrode of only CNT can be realized.

(3) Cracking of plastic substrate

In the case of a plastic substrate, in order to form a conductive metal film and use it as an electrode, the thickness of the conductive metal film deposited on the plastic film becomes thick, thereby causing peeling due to the difference in flexibility between the plastic substrate and the metal layer, And the function of the electrode may be lost. However, in the case of the plastic substrate according to an embodiment of the present invention, the thickness of the conductive metal film can be made thinner by introducing the resin layer in which the conductive material is dispersed together with the conductive metal film, and the conductive metal film and the conductive It is possible to reduce the problems of peeling and cracking of the conductive metal film due to the difference in dimensional stability caused by bending due to the resin of the resin layer in which the conductive material rising on the metal film is dispersed, And the peel resistance and the uniformity against bending of the substrate can be improved.

Concrete evaluation results are not shown in Table 3 in this regard.

(4) Gas and moisture barrier properties

- Oxygen Permeability (OTR)

The average value was determined by measuring 10 times at 23 DEG C and 0% RH in accordance with ASTM D-39859 using Mocon Oxytran 1000.

- Water permeability (WVTR)

The average value was determined by measuring 10 times at 38 DEG C and 90% RH according to ASTM F-1249 using Mocon Aquatran Model 1.

Since the film itself contains air or moisture and has high air permeability and moisture permeability, air or water enters the liquid crystal layer or the organic light emitting element layer from the outside air or the film, bubbles are generated, And the organic light emitting device or the like are oxidized to reduce the life of the display device and deteriorate the display device. In order to solve this problem, it is possible to form a multilayer of a monolayer inorganic layer or an organic layer / inorganic layer on the inner and / or outer surface of a film used as a substrate to form a barrier layer for shielding gas and moisture. That is, not only air and moisture of outside air, but also air and moisture contained in the film itself can be blocked.

However, the conductive metal film included in the plastic substrate of the present invention is formed on the plastic film serving as a substrate to serve not only as an electrode but also as a gas barrier layer, thereby reducing the manufacturing cost of the display device and improving the lifetime. Can be confirmed from the results of the oxygen permeability and the water permeability in Table 3.

Surface resistance
(Ω / Sq) Permeability
(500 nm,%) OTR
(cc / M ² Day) WVTR
(g / M ² Day) Example 1 2.2 x 10 ⁶ 81.2 0.025 0.068 Example 2 1.9x10 ⁶ 81.2 0.02 0.054 Example 3 4.2 x 10 ⁵ 83.4 0.01 0.028 Example 4 2.2x10 ² 80.1 0.004 0.012 Example 5 5.0x10 ⁵ 79.7 0.029 0.059 Example 6 2.0x10 ⁵ 81.5 0.022 0.051 Example 7 4.2 x 10 ⁴ 84.4 0.01 0.035 Example 8 6.0x10 ¹ 81.1 0.004 0.016 Example 9 3.6 x 10 ² 85.2 0.0096 0.03 Example 10 7.0x10 ¹ 85.6 0.0032 0.012 Comparative Example 1 > 10 ¹³ 89.3 57 17.8 Comparative Example 2 3.2x10 ¹¹ 89 20.9 8 Comparative Example 3 2.2 x 10 ³ 75 3.5 5 Comparative Example 4 1.2x10 ¹ 54 1.7 1.2 Comparative Example 5 3.0x10 ⁸ 77.3 0.9 3 Comparative Example 6 1.9x10 ⁷ 75.2 0.5 1.1 Comparative Example 7 4.2 x 10 ⁶ 72.2 0.29 0.9

Examples 11 to 23 and Comparative Examples 8 to 14 (Examples of Production of Transparent Electrode Film)

An ITO vapor deposition film or an IZO vapor deposition film was formed on each of the plastic films obtained in Production Examples 1 to 5 and then an ITO vapor deposition layer or an IZO vapor deposition layer was formed by photolithography and etching to form a stripe transparent electrode.

A polyimide varnish in which carbon nanotubes (SWNT, CNI) are dispersed in an amount of 0.001 to 1% by weight based on the solid content of a transparent polyimide resin on an ITO or IZO transparent electrode (polyimide varnish having a polyimide composition obtained from Production Examples 1 to 5 Polyamic acid composition) was applied as a thin film by casting or spraying to form a resin layer in which carbon nanotubes were dispersed. In another embodiment of the invention to form a resin layer by further mixing and dispersing 5 to 25 parts by weight of ITO powder with respect to 100 parts by weight of the polyimide resin solid content in forming the resin layer dispersed in the CNT prepared above (execution) Examples 20-21).

 The thickness of the ITO or IXO deposited film, the carbon nanotube content in the resin layer in which the carbon nanotubes are dispersed, the ITO powder content, and the thickness are shown in Table 4 below.

Plastic film ITO deposition film IZO deposition film Dispersion of conductive material
Resin layer thickness
(nm) thickness
(nm) thickness
(um) CNT content * ITO powder content * Example 11 Production Example 1 50 - 0.4 0.01 ^- Example 12 Production Example 2 50 - 1.2 0.01 ^- Example 13 Production Example 1 50 - 2.5 0.01 ^- Example 14 Production Example 5 100 - 0.4 0.02 ^- Example 15 Production Example 1 100 - 1.2 0.02 ^- Example 16 Production Example 2 100 - 2.5 0.02 ^- Example 17 Production Example 1 150 - 0.4 0.05 ^- Example 18 Production Example 5 150 - 1.2 0.05 ^- Example 19 Production Example 1 150 - 2.5 0.05 ^- Example 20 Production Example 1 50 - 2.5 0.01 5 Example 21 Production Example 1 50 - 2.5 0.01 25 Example 22 Production Example 1 - 100 2.5 0.01 - Example 23 Production Example 1 - 150 2.5 0.01 - Comparative Example 8 Production Example 2 50 - - - ^- Comparative Example 9 Production Example 3 100 - - - ^- Comparative Example 10 Production Example 1 150 - - - ^- Comparative Example 11 Production Example 1 200 - - - ^- Comparative Example 12 Production Example 1 300 - - - ^- Comparative Example 13 Production Example 1 - - - - 25 Comparative Example 14 Production Example 1 - 150 - - - (week)
* Expressed as parts by weight based on 100 parts by weight of the polyamic acid solid content in the varnish

Experimental Example 2

The transparent electrode films obtained in Examples 11 to 23 and Comparative Examples 8 to 14 were evaluated as follows, and the results are shown in Table 5 below.

(1) Optical characteristics

The visible light transmittance of the prepared transparent electrode film was measured using a UV spectrometer (Varian, Cary100).

From the results in Table 5, it can be seen that as the thickness of the ITO or IZO deposition layer increases, the surface resistance decreases and the transmittance increases. However, when the thickness of the ITO layer (or IZO layer) is increased to 200 to 300 nm or more, bending of the electrode film causes peeling between the ITO layer (or IZO layer) and the plastic film and cracking of the ITO layer (or IZO layer) In the case of an electrode in which the performance is impaired and the ITO is thickly raised, the banding itself is difficult or the flexibility of the substrate is extremely small, so that flexibility which is one of the objects of the present invention can be reduced.

Therefore, when a conductive material-dispersed resin layer is formed on the ITO layer (or the IZO layer) according to the embodiment of the present invention, the ITO layer (or the ITO layer) required to realize the same surface resistance as the transparent electrode film having only the ITO layer IZO layer), and the amount of the conductive material in the conductive material-dispersed resin layer at this time can also reach the surface resistance desired to be achieved with only a very small amount due to the presence of the ITO layer (or the IZO layer) Since the dispersion of the conductive material dispersed resin layer is also a highly transparent colorless resin, a similar level of transmittance can be exhibited as compared with the thick film formed only of the ITO layer (or IZO layer). In addition, as described below, the transparent electrode film including the conductive material dispersed resin layer according to the embodiment of the present invention also enables the correction function for peeling and cracking of the ITO layer (or IZO layer).

(2) surface resistance

The surface resistance was measured using a high resistance meter (Hiresta-UP MCT-HT450 (Mitsuibishi Chemical Corporation), a measuring range of 10 10 ^-5 to 10 10 ¹⁵ ) and a low resistance meter (CMT-SR 2000N (Advanced Instrument Teshnology; - Point Probe System, measurement range: 10 × 10 ^-3 to 10 × 10 ⁵ ).

As shown in Table 4 below, it can be seen that the transparent electrode according to the embodiment of the present invention can have a lower surface resistance than the transparent electrode having only CNT based on the same amount of CNTs. Therefore, it can be understood that a transparent electrode having excellent transparency compared to a transparent electrode of only CNT can be realized.

(3) ITO Banding

The results of Table 4 show that as the thickness of the ITO deposition increases, the surface resistance decreases and the transmittance increases. However, when the electrode film is bent according to the increase of the thickness of the ITO layer, cracks are generated in the ITO layer and the performance is impaired. In the case of the ITO thick electrode, the banding itself is difficult or the flexibility of the substrate is extremely small. However, according to one embodiment of the present invention, when a resin layer containing a conductive material is dispersed on the ITO deposition layer (or the IZO deposition layer), the thickness of the ITO layer for achieving a relatively required surface resistance and light transmittance is reduced The flexibility of the transparent electrode is increased as compared with the electrode film of the conventional structure, and the ITO layer (or the IZO layer) is protected by the flexible polymer resin at the top and the bottom due to the resin of the resin layer in which the conductive material is dispersed, The occurrence rate of cracks due to bending is reduced.

As described above, according to the embodiments of the present invention, the electrical conductivity is excellent, and even if the thickness is reduced, the transmittance can be improved. In addition, compared with the single-layer transparent electrode made of the conventional CNT or ITO, A thin film and a transparent electrode having excellent permeability can be obtained.

Since Ag, Mg, and Ba are metals, it is easy to make Ohmic contact at junctions with devices such as TFTs in the production of active matrix panels. In manufacturing organic EL devices, Ag Is used as an anode, and a transparent electrode containing Ca or Mg can be used as a cathode.

Surface resistance
(Ω / Sq) Permeability
(500 nm,%) OTR
(cc / M ² Day) WVTR
(g / M ² Day) Example 11 7.0 x 10 ² 88.2 0.026 0.06 Example 12 4.7x10 ² 87.9 0.024 0.051 Example 13 2.8x10 ² 87.7 0.018 0.047 Example 14 5.0 x 10 ² 86.9 0.0085 0.035 Example 15 2.0x10 ² 86.2 0.0077 0.03 Example 16 6.0x10 ¹ 85.8 0.0068 0.027 Example 17 5.0x10 ¹ 86.3 0.006 0.022 Example 18 3.0x10 ¹ 85.8 0.0045 0.016 Example 19 2.3x10 ¹ 85.1 0.004 0.012 Example 20 4.5x10 ¹ 88.2 0.0038 0.011 Example 21 2.2x10 ¹ 88.2 0.0015 0.006 Example 22 1.5x10 ² 86.4 0.004 0.013 Example 23 5.2x10 ¹ 87.3 0.0017 0.007 Comparative Example 8 2.0x10 ³ 87.2 0.03 0.062 Comparative Example 9 7.0 x 10 ² 86.9 0.01 0.041 Comparative Example 10 5.0 x 10 ² 87.8 0.0069 0.027 Comparative Example 11 4.0x10 ¹ 87.5 0.004 0.015 Comparative Example 12 6.0x10 ⁰ 86.7 0.003 0.011 Comparative Example 13 4.0x10 ² 87.1 0.04 0.15 Comparative Example 14 8.0x10 ² 87.9 0.0045 0.019

Reference Examples 1 to 6 and Comparative Samples

On each of the plastic films (thickness 50 μm) obtained from Production Examples 1 to 5, a reflective metal film was formed by depositing a reflective metal as shown in Table 6 below, and reflectance of the formed metal film was measured.

The structure of the reflecting material used for evaluation of a reflection characteristic is demonstrated.

First, by forming a metal film on the surface of the plastic substrate by the above-described manufacturing method, and forming an electrode layer using a transparent plastic protective layer or a transparent plastic resin on the metal film, the plastic of the plastic substrate and the metal film formed thereon The board | substrate was manufactured and it was set as the evaluation sample.

The evaluation of the reflective characteristics is that the external light passes through the front portion of the liquid crystal display device as the metal film is formed under the transparent protective layer or the transparent electrode layer in the structure of the reflective liquid crystal display device in the plastic substrate. After passing through the polyimide film, the metal film was diffusely reflected.

The measuring system used for the measurement of the brightness of a reflecting material is demonstrated.

An example thereof is shown in Fig. 14, where a luminance meter is arranged at a predetermined position on the upper side of the plastic substrate on which the reflecting plate is formed, and a light source is arranged on the side surface of the reflecting plate. The angle formed by the incident light emitted from the light source and the reflected light is defined as the incident angle θ, and the light source can move to a predetermined position so as to vary the incident angle θ. White light was used as a light source, and the polarizing film was used as the measuring system. Subsequently, the white light is emitted from the light source while the incident angle θ is changed to a range of 7.4 ^{° to} 35.6 ^° , and the luminance angle of the light reflected from the metal film is measured by a luminance meter, thereby investigating the incident angle θ dependency of the brightness. It was.

In addition, a ceramic type standard white diffuser plate was prepared, and the incident angle θ dependence of the luminance of light reflected from the standard white diffuser plate was measured by the above-described measuring method, and this was taken as the reference value of the light reflection luminance.

Then, the luminance value obtained from the plastic substrate was divided by the luminance value of the standard white diffuser plate, and the value obtained by multiplying this by 100 was obtained. That is, the relative luminance value of the plastic substrate when the luminance of the standard white diffuser plate was set to 100 was obtained.

The results are shown in Table 6 below.

plastic
film Reflective metal film Reflective property evaluation
Kinds thickness
(nm) 7.4 ^о 17.7 ^о 22.3 ^о 26.6 ^о 31.8 ^о 35.6 ^о Reference Example 1 Production Example 1 Mg 10 486 249 196 112 91 14 Reference Example 2 Production Example 2 Mg 10 470 267 218 122 109 19 Reference Example 3 Production Example 5 Mg 50 468 264 204 128 112 14 Reference Example 4 Production Example 1 Al 10 493 278 218 99 91 11 Reference Example 5 Production Example 2 Al 10 487 280 220 130 116 15 Reference Example 6 Production Example 5 Al 50 476 284 210 138 122 29 Comparative Sample - - - 443 279 222 173 134 91

From the results of Table 6, in the plastic substrate according to the forming the metal film will be described the results of the evaluation of the reflection property, the incident angle (θ) is 7.4 ^о, 17.7 ^о, 22.3 ^о the luminance of the comparison sample and the reflected light substantially the same when the However, about 2.2 to 4.4 times the luminance was obtained for the standard white diffuser plate.

As described above, the plastic substrate manufactured by the method of manufacturing the reflector according to the embodiment of the present invention obtains higher luminance than the standard white diffuser at most incident angles of the light, and at the same time the incident light having a large incident angle? It was found that the luminance of the reflection of the incident light on the side surface can be made higher than that of the comparative sample.

Alternatively, although the evaluation was performed in a state in which a transparent electrode layer was formed on a metal film in a plastic substrate, that is, a structure in which incident light was diffused and reflected through a polyimide film, a light reflectance higher than that of a standard white diffuser plate was obtained. Since the polyimide membrane had high transparency, it was confirmed that there was no problem even in such a structure.

In addition, it goes without saying that even in the form in which light is emitted from the metal film side, it has a reflection characteristic equivalent to or higher than the present evaluation result.

In addition, since the plastic substrate of the present invention has the same refractive index over the entire polyimide film, even when the incident light is arranged to diffusely reflect through the polyimide film, it can be used as a reflective material with little occurrence of polarization extinction effect.

That is, although not specifically stated, in the above-described measuring system, the luminance La when the polarizing films are arranged parallel to each other on the light source side and the luminance measurement, and the polarizing films having the polarization axes perpendicular to each other are arranged on the light source side and the luminance measurement. When the luminance Lb in one case is measured and the La / Lb value (contrast ratio) is calculated, a La / Lb value larger than that of the reflective material having a different refractive index in the conventional resin can be obtained. This means that the plastic substrate according to the present invention is a reflective material with little occurrence of polarization extinction effect.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a cross-sectional view of a flat panel display device, in which (a) is a liquid crystal display device element, and (b) to (c)

2 is a sectional view of a plastic substrate according to an embodiment of the present invention.

Figures 3 to 10 are cross-sectional views illustrating various embodiments of the plastic substrate of the present invention.

11 is a sectional view of an LCD device to which a plastic substrate according to an embodiment of the present invention is applied.

12 is a sectional view of an organic EL device to which a plastic substrate according to an embodiment of the present invention is applied.

13 is a sectional view of a transmission type organic EL device to which a plastic substrate according to an embodiment of the present invention is applied.

14 illustrates an example of a luminance measuring method for measuring reflectivity of a plastic substrate manufactured according to an embodiment of the present invention.

Description of the Related Art [0002]

1: glass substrate, 11: ITO electrode

100: plastic substrate, 101: inorganic layer

102: UC (chemical layer), 103: protective layer (planarization layer)

110: conductive and / or reflective metal film, 112: metal electrode

113: reflective electrode, 111: oxide film

120: a resin layer in which a conductive material is dispersed, 130:

140: barrier rib, 150: liquid crystal

160: organic light emitting layer

Claims (42)

Plastic film; A reflective and / or electrically conductive metal film formed on the plastic film; A protective layer formed on the metal film; And It includes a resin layer in which a conductive material formed on the protective layer is dispersed, The protective layer has an average linear expansion coefficient (CTE) of 50.0 ppm / ° C or less measured by a thermomechanical method based on a thickness of 50 to 100 μm, and a UV spectrophotometer based on a thickness of 50 to 100 μm. The plastic substrate which is a polyimide layer whose average transmittance in 380-780 nm is 85% or more when the transmittance | permeability is measured by the furnace. The reflective metal of claim 1, wherein the metal film is selected from aluminum, titanium, silver, platinum, magnesium, tantalum, palladium and alloys thereof, indium tin oxide (ITO), and indium zinc oxide (IZO). Membrane plastic substrate. The plastic substrate of claim 2, wherein the reflective metal film is selected from aluminum, magnesium, and alloys thereof. The method of claim 2, wherein the reflective metal film is a lower metal film selected from aluminum, magnesium and alloys thereof; A plastic substrate comprising an upper metal film of indium tin oxide or indium zinc oxide. The plastic substrate according to claim 2, wherein the reflective metal film has a thickness of 10 to 1,000 nm. The plastic substrate according to claim 2, wherein the reflective metal film has a thickness of 50 to 300 nm. The method of claim 1, wherein the metal film is selected from magnesium, barium, gold, aluminum, titanium, silver, platinum, tantalum and palladium alone, alloys and oxides thereof; A plastic substrate which is an electrically conductive metal film selected from indium tin oxide and indium zinc oxide. 8. The plastic substrate of claim 7, wherein the electrically conductive metal film is indium tin oxide or indium zinc oxide. 8. The plastic substrate according to claim 7, wherein the electrically conductive metal film is made of one or an oxide thereof selected from magnesium, barium and gold. 8. The plastic substrate according to claim 7, wherein the electrically conductive metal film is made of indium tin oxide. 8. The plastic substrate according to claim 7, wherein the electrically conductive metal film has a thickness of 1 to 300 nm. 8. The plastic substrate of claim 7, wherein the electrically conductive metal film has a thickness of 1 to 100 nm. 8. The plastic substrate of claim 7, wherein the electrically conductive metal film has a thickness of 1 to 50 nm. The plastic substrate of claim 1, wherein the metal film is a gas barrier film or a moisture barrier film. The plastic substrate according to claim 1, wherein the plastic film is a polyimide film. The method according to claim 1, wherein the plastic film has a polyolefin having an average coefficient of linear expansion (CTE) of 50.0 ppm / 占 폚 or less and a yellowness of 15 or less, measured by a thermomechanical method based on a film thickness of 50 to 100 μm. The plastic substrate which is a mid film. The method of claim 1, wherein the plastic film is a polyimide film having an L value of 90 or more, an a value of 5 or less, and a b value of 5 or less when the color coordinate is measured by a UV spectrophotometer based on a film thickness of 50 to 100 µm. Plastic substrate. delete The plastic substrate of claim 1, wherein the protective layer is a polyimide layer having a yellowness of 15 or less based on a thickness of 50 to 100 μm. delete The plastic substrate of claim 1, wherein the protective layer is a polyimide layer having a transmittance of 88% or more at 550 nm and a transmittance of 70% or more at 420 nm when the transmittance is measured by a UV spectrophotometer based on a thickness of 50 to 100 μm. The plastic substrate of claim 1, wherein the conductive material is carbon nanotube or indium-tin oxide powder. The plastic substrate of claim 1, wherein the resin layer in which the conductive material is dispersed is formed from a polyimide varnish in which the conductive material is dispersed. The plastic substrate of claim 1, wherein the resin layer in which the conductive material is dispersed is formed from a polyimide varnish containing 0.001 to 1 parts by weight of carbon nanotubes based on 100 parts by weight of a polyimide resin solid content. The plastic substrate according to claim 1, wherein the resin layer in which the conductive material is dispersed is formed from a polyimide varnish containing 2 to 100 parts by weight of indium-tin oxide powder with respect to 100 parts by weight of a polyimide resin solid content. 26. The plastic substrate of claim 22 or 25, wherein the indium tin oxide powder contains 80 to 95 weight percent indium oxide and 5 to 20 weight percent tin oxide. The plastic substrate of claim 1, wherein the resin layer in which the conductive material is dispersed has a thickness of 10 nm to 25 μm. The plastic substrate of claim 1, further comprising a chemical resistant layer on at least one surface of the plastic film. 29. The plastic substrate of claim 28, wherein the chemical resistant layer is a layer comprising at least one resin selected from acrylic resin, epoxy resin, polysilazane, and polyimide resin. The plastic substrate of claim 1, further comprising an inorganic layer formed under the plastic film or under the metal film. 31. The plastic substrate of claim 30, wherein the inorganic layer is a single layer or a multilayer comprising at least one inorganic material selected from SiNx, AlxOy, and SiOx.  The plastic substrate of claim 1, further comprising a metal oxide layer formed on an upper surface or a lower surface of the resin layer in which the conductive material is dispersed. 33. The plastic substrate of claim 32, wherein the metal oxide layer is a layer made of AgO. The plastic substrate according to claim 1, wherein the light transmittance of 500 nm wavelength is 50% or more. The surface resistance of claim 1, wherein the surface resistance is 2.5 × 10 ⁶ Ω / sq. The plastic substrate which is below. Plastic film; An indium tin oxide or indium zinc oxide thin film formed on the plastic film and having a predetermined pattern; A protective layer formed on the thin film; And A resin layer in which a conductive material is dispersed, formed on the protective layer, The protective layer has an average linear expansion coefficient (CTE) of 50.0 ppm / ° C or less measured by a thermomechanical method based on a thickness of 50 to 100 μm, and a UV spectrophotometer based on a thickness of 50 to 100 μm. The transparent electrode film which is a polyimide layer whose average transmittance at 380-780 nm is 85% or more when the transmittance | permeability is measured by the furnace. The transparent electrode film of claim 36, wherein the conductive material is carbon nanotube or indium-tin oxide powder. 37. The transparent electrode film of claim 36, wherein the light transmittance of 500 nm wavelength is at least 50%. 38. The method of claim 37, wherein the surface resistance is 700? / Sq. Transparent electrode film which is below. A transmission type electronic paper device comprising the plastic substrate of claim 1 as a lower substrate. A display device element comprising the plastic substrate of claim 1 as a lower substrate. An organic light emitting device comprising the plastic substrate of claim 1 as a lower substrate.

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