JP2009059666A - Film with transparent conductive layer, flexible functional element, and production method thereof - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide various kinds of flexible functional elements, such as a film with a transparent conductive layer, a dispersive EL element, with excellent flexibility, high transparency and stable conductivity. <P>SOLUTION: The film with the transparent conductive layer has a patterned auxiliary electrode layer formed on a base film, and the transparent conductive layer formed on the base film and the patterned auxiliary electrode layer by means of a coating method. The base film is 3 to 200 μm thick. The patterned auxiliary electrode layer is formed of a thin film having a thickness of 0.02 to 0.2 μm with a metal as a main component. The transparent conductive layer is 2 to 10 times as thick as the patterned auxiliary electrode layer with a fine particle of a conductive oxide and a binder matrix as the main components, and a compression process is performed to the transparent conductive layer. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  In the present invention, a pattern auxiliary electrode layer having a thickness of 0.02 to 0.2 μm mainly composed of metal and a transparent conductive layer mainly composed of conductive oxide fine particles and a binder matrix are sequentially formed on a base film. A film with a transparent conductive layer and a liquid crystal display element obtained using the film with the transparent conductive layer, an organic electroluminescence element, an inorganic dispersion type electroluminescence element, an electronic paper element, a flexible functional element of any one of touch panel elements, and those It is related with the manufacturing method.

In recent years, in electronic devices such as various displays such as liquid crystal displays and mobile phones, the movement of thinning and thinning is accelerating, and along with this, research on replacing glass substrates that have been used conventionally with plastic films is actively conducted. Has been done. Since a plastic film is light and excellent in flexibility, a thin plastic film having a thickness of about several μm is used as, for example, a liquid crystal display element, an organic electroluminescence element (hereinafter abbreviated as “organic EL element”), an electronic paper element, If it can be applied to an inorganic dispersion type electroluminescence element (hereinafter abbreviated as “dispersion type EL element”), a touch panel element, etc., it becomes possible to obtain an extremely light and flexible functional element.
Among the above functional elements, the dispersion type EL element is a light emitting element driven by an alternating voltage, and has been conventionally used for a small backlight of a liquid crystal display such as a mobile phone and a remote controller. Recently, it has been used for large display devices such as backlights for point-of-sale product advertisements (POP advertisements) at stores and light-emitting elements incorporated in night-time display lamps.

As a manufacturing method of such a dispersion type EL element, generally, a physical film forming method such as sputtering or ion plating is used, and a transparent conductive layer (hereinafter referred to as “ITO”) of indium tin oxide (hereinafter referred to as “ITO”) is used. A method of further forming a phosphor layer, a dielectric layer, and a back electrode layer on a plastic film (hereinafter abbreviated as “sputtering ITO film”) on which an ITO layer is abbreviated by screen printing or the like. Widely known.
Here, the sputtering ITO film has an ITO single layer, which is an inorganic component, on a transparent plastic film such as polyethylene terephthalate (PET) or polyethylene naphthalate (PEN). Thus, a transparent conductive layer having a low resistance with a surface resistance value of about 100 to 300 Ω / □ (read as ohm-per-square) can be obtained.

  However, the sputtered ITO layer is a thin film of an inorganic component and is extremely brittle, so it tends to cause microcracking. For example, when applied to a flexible element using a plastic film as a base film, the functional deterioration of the element is deteriorated. It is easy to cause, especially when the element is large (for example, about 50 cm × 50 cm or more), the above-mentioned functional deterioration due to film breakage during handling is remarkable, and the handling in the manufacturing process of the element is also hindered. There was a problem of coming.

  Moreover, PET film is widely used as the base film of the above-mentioned sputtering ITO film. However, when the thickness is less than 50 μm, the flexibility of the base film is too high, and sputtering is performed during handling. Since the ITO layer is easily cracked and the conductivity of the film is remarkably impaired, for example, a thin sputtering ITO film having a thickness of 16 μm or the like has not been put into practical use for a device that requires high flexibility. Met.

In order to improve the handling of the thin PET film, it is also attempted to form a sputtered ITO film on the base film using a base film with a thickness of less than 50 μm lined with a support film having a thickness of about 75 μm to 125 μm. However, in this case as well, since the flexibility of the sputtering ITO layer itself is poor, there is a problem that if the support film is peeled and removed, the conductive properties and flexibility of the sputtering ITO layer cannot be achieved at the same time.
Moreover, even if the soft base film such as urethane has a film thickness of 75 μm or more, the present situation is that cracks are likely to occur when a sputtering ITO layer is formed and has not been put into practical use.

  Therefore, when a dispersion type EL element is produced using a conventional sputtering ITO film to be applied to the large display device described above, the thickness of the base film is at least 100 μm or more in order to prevent cracking of the sputtering ITO layer ( It is necessary to increase the rigidity of the film, preferably 150 μm or more, and the base film made of a flexible material cannot be used. Therefore, the dispersed EL element cannot be stored and transported in a rolled state, which is inconvenient to handle. In addition, there is a problem that the weight of the element itself increases.

Therefore, instead of forming the ITO layer by sputtering, for example, as disclosed in Patent Documents 2 to 6, as a method for forming a relatively flexible transparent conductive layer on a plastic base film, conductive oxide fine particles and a binder matrix are used. A method is known in which a coating solution for forming a transparent conductive layer mainly containing sapphire is applied and dried on a base film, then subjected to compression (rolling) treatment with a metal roll, and then the binder component is cured.
This method has an advantage that the electrical (conductive) characteristics and optical characteristics of the film can be greatly improved by increasing the packing density of the conductive fine particles in the transparent conductive layer by rolling with a metal roll. However, the film with a transparent conductive layer obtained by the above method is insufficient from the viewpoint of achieving both excellent transparency and conductivity. For example, when the visible light transmittance is about 90%, the resistance is about several hundred Ω / □. It was difficult to obtain a transparent conductive layer having a low resistance of several tens Ω / □ or less. Moreover, it cannot be said that the stability (change with time) of the resistance value is sufficient. For example, when the resistance value is left in the atmosphere, a phenomenon in which the resistance value gradually increases may occur.
Here, in a large dispersion type EL element (for example, about 50 cm × 50 cm or more), when the resistance value of the transparent conductive layer is increased to about several hundreds Ω / □, the voltage applied to the central part of the element is lowered and the luminance is increased. Therefore, it is necessary to reduce the resistance value to about several tens of Ω / □ or less while keeping the visible light transmittance high.

As described above, even with the above-described method for forming a transparent conductive film by a conventional coating method, the flexibility required for the dispersion-type EL element and the increase in the size of the element still cannot be sufficiently dealt with. .
In addition, as in the case of the above-described dispersion type EL element, the flexible functional elements such as the above-described liquid crystal display element, organic EL element, electronic paper element, touch panel element and the like are required for the production of these flexible functional elements. A film with a transparent conductive layer having a transparent conductive layer formed on a base film (plastic film), having excellent transparency and flexibility, high conductivity and stable conductivity (not changing with time) Was not obtained.
Japanese Patent Laid-Open No. 2001-274331 JP-A-4-237909 JP-A-5-036314 JP 2001-321717 A JP 2002-36411 A JP 2002-42558 A

  The present invention has been made in view of such a conventional situation, and is excellent in flexibility and high in comparison with various functional elements such as a conventional sputtering ITO film and a dispersion type EL element using the film. Various flexible functional elements such as a film with a transparent conductive layer that has transparency and conductivity, and whose conductivity is stable (a change with time is suppressed), and a flexible dispersion type EL element, specifically, A film with a transparent conductive layer having a good handling property using a flexible base film, and a liquid crystal display element, an organic EL element, an electronic paper element, a touch panel element, or a dispersion type EL element using the film with a transparent conductive layer An object of the present invention is to provide such a flexible functional element and a method for producing the same.

The film with a transparent conductive layer according to the present invention is a film with a transparent conductive layer in which a pattern auxiliary electrode layer is formed on a base film, and a transparent conductive layer is further formed on the base film and the pattern auxiliary electrode layer by a coating method. The base film has a thickness of 3 to 200 μm, the pattern auxiliary electrode layer is a thin film having a thickness of 0.02 to 0.2 μm mainly composed of metal, and the transparent conductive layer is formed of the pattern auxiliary electrode layer. It has a thickness of 2 to 10 times the thickness, is mainly composed of conductive oxide fine particles and a binder matrix, and is further subjected to a compression treatment.
Here, the thickness of the base film is preferably 3 to 25 μm, and a fine adhesive layer that can be peeled off at the interface with the base film is formed on the surface of the film with the transparent electric layer where the transparent conductive layer is not formed. A preferred embodiment is that the supporting film is lined. Furthermore, the peel strength between the fine adhesive layer and the base film (force required for peeling per unit length in the peeled portion) is preferably 1 to 15 g / cm regardless of the presence or absence of the heat treatment step, Furthermore, it is preferable that both the dimensional change rate (heat shrinkage rate) in the vertical direction and the horizontal direction of the film with a transparent conductive layer are 0.3% or less.

  Further, the pattern auxiliary electrode layer in the present invention preferably contains one or more of aluminum, nickel, chromium, silver as a main component, and the pattern auxiliary electrode layer has a lattice shape, a mesh shape, It is preferable to have a honeycomb shape, a parallel line shape, or a comb tooth shape. Furthermore, the conductive oxide fine particles according to the present invention preferably contain one or more of indium oxide, tin oxide, and zinc oxide as the main component, and the conductive oxide fine particles mainly contain the indium oxide. Are preferably indium tin oxide fine particles. Furthermore, it is preferable that the binder matrix in the present invention is crosslinked and has an organic solvent resistance. In the present invention, it is preferable that the compression treatment is performed by rolling a metal roll.

  Moreover, the flexible functional element according to the present invention is a liquid crystal display element, an organic electroluminescence element, an inorganic dispersion type electroluminescence element, an electronic paper element, or a touch panel element on the transparent conductive layer of the film with a transparent conductive layer. When the functional element is formed and the support film having a slightly adhesive layer is lined with the base film, the support film is peeled off at the interface between the base film and the slightly adhesive layer. It is characterized by.

Next, the method for producing a film with a transparent conductive layer according to the present invention is a method for producing a film with a transparent conductive layer in which a pattern auxiliary electrode layer and a transparent conductive layer are formed on the surface of a base film having a thickness of 3 to 200 μm. Then, after forming a pattern auxiliary electrode layer having a thickness of 0.02 to 0.2 μm mainly composed of metal on the surface of the base film, a conductive oxide is formed on the base film and the pattern auxiliary electrode layer. A coating layer was formed using a coating liquid for forming a transparent conductive layer mainly composed of fine particles, a binder, and a solvent, and then a compression treatment was performed on the base film and the pattern auxiliary electrode layer on which the coating layer was formed. Thereafter, the compression-treated coating layer is cured to form a transparent conductive layer having a thickness of 2 to 10 times the thickness of the pattern auxiliary electrode layer.
Here, the base film is backed by a support film having a slightly adhesive layer that can be peeled off at the interface with the base film, and the pattern auxiliary electrode layer and the transparent film are not backed by the support film of the base film. It is preferable that the conductive layers are sequentially formed. In addition, the pattern auxiliary electrode layer is formed on a thin film having a thickness of 0.02 to 0.2 μm mainly composed of a metal formed on a base film by a physical film forming method, and a photolithography process (photoresist patterning and etching). ) Can be applied. Furthermore, the pattern auxiliary electrode layer can be formed by pattern-printing an auxiliary electrode layer forming coating liquid mainly composed of metal nanoparticles on a base film. In addition, the said compression process can be performed by applying the rolling process of a metal roll, and the said rolling process has preferable linear pressure: 29.4-490N / mm (30-500kgf / cm).

  Moreover, the manufacturing method of the flexible functional element which concerns on this invention is a liquid crystal display element, an organic electroluminescent element, an inorganic dispersion type electroluminescent element, an electronic paper element, a touch panel on the transparent conductive layer of the said film with a transparent conductive layer. When any one of the functional elements of the element is formed and the support film having the slightly adhesive layer is lined with the base film, the support film is peeled off at the interface between the base film and the slightly adhesive layer. It is characterized by.

  The film with a transparent conductive layer of the present invention has excellent flexibility and high transparency and conductivity as compared with various functional elements such as a conventional sputtering ITO film and a dispersion type EL element using the film. In addition, the conductivity is stable (a change with time is suppressed), and according to the method of the present invention, various flexible functionalities incorporating a film with a transparent conductive layer and a dispersive EL element using the same are incorporated. An element can be provided at low cost. Furthermore, when the film with a transparent conductive layer is applied to a dispersion-type EL element, the transparent conductive layer has high transparency, and its resistance value is sufficiently low, so that it is a large element excellent in high luminance and light emission uniformity. Can be obtained. Furthermore, since the temporal change in the resistance value of the transparent conductive layer is suppressed, it can be used as a transparent electrode for various flexible functional elements such as liquid crystal display elements other than dispersed EL elements, organic EL elements, electronic paper elements, and touch panel elements. Is preferred.

  Examples of the flexible functional element to which the film with a transparent conductive layer of the present invention can be applied include a liquid crystal display element, an organic EL element, an electronic paper element, a touch panel element, and a distributed EL element.

  Liquid crystal display elements are non-light-emitting electronic display elements widely used for displays such as mobile phones, PDAs, and PCs. There are simple matrix systems and active matrix systems, and active matrix systems in terms of image quality and response speed. Is excellent. Its basic structure is to display by sandwiching liquid crystal between transparent electrodes and aligning liquid crystal molecules with voltage drive. In addition to the above transparent electrodes, the actual elements are color filters, retardation films, polarizing films, etc. Are used in layers.

  Unlike a liquid crystal display element, an organic EL element is a self-luminous element and is expected to be used as a display device such as a display because high luminance can be obtained by low voltage driving. The structure consists of a hole injection layer (hole injection layer) made of a conductive polymer such as a polythiophene derivative, an organic light emitting layer (deposited low molecular light emitting layer or coating formation) on a transparent conductive layer as an anode electrode layer. Polymer light-emitting layer), cathode electrode layer (metal layer with good electron injection into the light-emitting layer, low work function magnesium (Mg), calcium (Ca), aluminum (Al), etc.), gas barrier coating layer ( Alternatively, a sealing process with metal or glass is sequentially formed.

  The electronic paper element is a non-light-emitting electronic display element that does not emit light by itself, has a memory effect that remains displayed even when the power is turned off, and is expected as a display for displaying characters. The display method includes an electrophoresis method in which colored particles are moved in a liquid between electrodes by an electrophoresis method, and a twist ball method in which particles having dichroism are colored by rotating in an electric field, such as transparent cholesteric liquid crystal. Liquid crystal system that displays by sandwiching between electrodes, powder system that displays by moving colored particles (toner) and electronic powder fluid (Quick Response Liquid Powder) in the air, color development based on electrochemical oxidation / reduction action And electrodeposition method in which a metal is deposited and dissolved by electrochemical oxidation / reduction, and display is performed by a color change associated therewith.

  As a touch panel element, a transparent touch panel used in an input device in combination with various display devices is generally used. Although there are differences in detection methods such as a resistance detection method, a capacitance method, an electromagnetic induction method, etc., at least one or more sheets are used. It is comprised from the transparent substrate which has a transparent conductive layer (transparent electrode). For example, a resistance detection type transparent touch panel is formed by sequentially forming an undercoat layer and a transparent conductive layer on a polymer film on a lower electrode made of a transparent conductive layer formed on a thick substrate such as glass or plastic. The upper electrode is laminated via a spacer (microdot spacer) so that the transparent conductive layers face each other. When the display surface of the upper electrode is pressed with a finger or a pen, the upper electrode and the lower electrode are A signal is input by contacting and energizing.

  The dispersion-type EL element is a self-luminous element that emits light by applying a strong electric field to a layer containing phosphor particles, which will be described in detail later.

  In any of the above functional elements, thinning, lightening, and flexibility of the elements are becoming more and more important issues. In addition, large dispersed EL elements as well as electronic paper elements and touch panel elements. In addition, there is a demand for lower resistance and higher transparency as well as cost reduction, and these problems can be achieved by applying the film with a transparent conductive layer of the present invention.

Hereinafter, the case where the film with a transparent conductive layer of the present invention is applied to a dispersion type EL element as a flexible functional element will be described with reference to the drawings. Needless to say, the other flexible functional elements can be applied in the same manner although there are differences in the manufacturing process of the elements.
FIG. 1 is a schematic sectional view showing an embodiment of a dispersion type EL element as a flexible functional element according to the present invention, FIG. 2 is a schematic sectional view showing a state in which the dispersion type EL element is backed by a support film, FIG. 3 is a schematic cross-sectional view showing an embodiment of a film with a transparent conductive layer in which a pattern auxiliary electrode layer and a transparent conductive layer are formed on the base film, and FIG. 4 shows a lattice-shaped pattern auxiliary electrode layer formed on the base film. FIG. 5 is a plan view of the transparent conductive layer-coated film formed on the base film so that the transparent conductive layer covers the pattern auxiliary electrode layer when viewed from the transparent conductive layer side. FIG. 6 is a schematic cross-sectional view showing another example of the structure of a conventional dispersion-type EL element. 1 is a transparent plastic film, 2 is a transparent conductive layer, and 3 is a phosphor. layer, Dielectric layer, 5 a back electrode layer 6 are current collecting electrode, 7 denotes an insulating protective layer, 8 a base film, 9 is patterned auxiliary electrode layer, 10 is a support film.

  First, a conventional dispersion type EL device will be described. As shown in FIG. 5, at least a transparent conductive layer 2, a phosphor layer 3, a dielectric layer 4, and a back electrode layer 5 sequentially formed on a transparent plastic film 1 are provided. Therefore, in application to an actual device, as shown in FIG. 6, it is common to further form and use a current collecting electrode 6 such as silver or an insulating protective layer 7.

On the other hand, the dispersion type EL element as the flexible functional element of the present invention has a pattern auxiliary electrode layer 9, a transparent conductive layer 2, a phosphor layer 3, which are sequentially formed on the base film 8, as shown in FIG. It has at least a dielectric layer 4 and a back electrode layer 5. Here, when the thickness of the base film 8 is as thin as about 25 μm or less, for example, as shown in FIG. 2, the support film 10 having a slightly adhesive layer (not shown) is inserted into the base via the slightly adhesive layer. A dispersion type EL element is manufactured in a state where the film 8 is lined, and finally, the support film 10 is peeled and removed at the interface between the base film 8 and the slightly adhesive layer.
In addition, although the said slightly adhesive layer exists between the support film 10 and the base film 8, when peeling the support film 10, it peels and removes together with this support film 10, but the raw material of the support film 10 itself is slightly adhesive. In the case of having the property, since the support film also has the function of the slightly adhesive layer, it is not particularly necessary to form the slightly adhesive layer on the support film. Further, although not shown in the dispersion type EL element of the present invention shown in FIGS. 1 and 2, like the conventional dispersion type EL element shown in FIG. Is generally formed and used.

  As described above, in the dispersion-type EL element as the transparent conductive layer-equipped film or the flexible functional element of the present invention, the thickness of 0.02 to 0.02 on the base film 8 is formed on the base film 8 as shown in FIG. After the pattern auxiliary electrode layer 9 having a thickness of 0.2 μm is formed, the transparent conductive layer 2 is formed on the base film 8 so as to cover the pattern auxiliary electrode layer 9, so that the pattern auxiliary electrode layer 9 is good. Conductivity and conductivity stability (suppression of resistance deterioration with time) are imparted to a film with a transparent conductive layer. Further, the transparent conductive layer 2 is 2 to 10 times as thick as the pattern auxiliary electrode layer 9, and since the metal is a main component, the pattern auxiliary electrode layer 9 having poor strength is physically protected, and at the same time, the pattern By covering the exposed portion of the base film 8 inside the pattern of the auxiliary electrode layer 9, conductivity is imparted to the portion, and the pattern auxiliary electrode layer 9 functions as the collecting electrode 6.

  Here, the pattern auxiliary electrode layer 9 needs to contain a metal as a main component. Metal is suitable for the material of the auxiliary electrode layer because it is excellent in conductivity and flexibility. Considering conductivity, film formability, flexibility, corrosion resistance, material cost, etc., any one of aluminum, nickel, chromium, and silver is used. It is preferable to contain one or more as main components. Aluminum and silver are excellent in conductivity and flexibility, and nickel and chromium are excellent in corrosion resistance.

  Moreover, the thickness of the said pattern auxiliary electrode layer 9 needs to be 0.02-0.2 micrometer. That is, if the thickness is less than 0.02 μm, the resistance value of the film with a transparent conductive layer becomes too high, and the effect of forming the pattern auxiliary electrode layer is not seen. On the other hand, if it exceeds 0.2 μm, the pattern auxiliary electrode layer is thick. When it is covered with a transparent conductive layer, the unevenness of the transparent conductive layer becomes large, and at the same time, the thickness of the transparent conductive layer becomes too thick, and the visible light transmittance of the film with a transparent conductive layer is too low. It is because it is not preferable.

  The pattern of the pattern auxiliary electrode layer 9 is not particularly limited as long as it has a shape that can achieve both transparency and conductivity of visible light. In short, it has a role of reducing the resistance value as an auxiliary electrode with an appropriate aperture ratio. That's fine. Preferable examples include a lattice shape, a mesh shape, a honeycomb shape, a parallel line shape, and a comb tooth shape. Since the aperture ratio of the pattern auxiliary electrode layer 9 greatly affects the visible light transmittance of the film with a transparent conductive layer, it is preferably larger, preferably about 90% or more, and more preferably about 95% or more.

  The film with a transparent conductive layer of the present invention shown in FIG. 4 is formed on the base film 8 so as to cover the pattern auxiliary electrode layer 9 with the transparent conductive layer 2 after the lattice-shaped pattern auxiliary electrode layer 9 is formed on the base film 8. And formed by a coating method.

Next, the transparent conductive layer 2 needs to be formed to a thickness of 2 to 10 times the thickness of the pattern auxiliary electrode layer 9. That is, when the thickness is less than twice, the effect of physically protecting the pattern auxiliary electrode layer 9 having poor strength is reduced, and at the same time, the unevenness of the transparent conductive layer 2 becomes large when covered with the transparent conductive layer. On the other hand, when the thickness exceeds 10 times, the thickness of the transparent conductive layer becomes too thick, and the visible light transmittance of the film with a transparent conductive layer is too low, which is not preferable. Since the conductivity of the pattern auxiliary electrode layer 9 is significantly higher than the conductivity of the transparent conductive layer 2, the effect of improving the resistance value of the film with the transparent conductive layer is small even if the transparent conductive layer 2 is made too thick. It just hurts the rate.
The transparent conductive layer 2 of the present invention is mainly composed of conductive oxide fine particles and a binder matrix, and is excellent in transparency and conductivity as described later because it is subjected to a compression treatment.

  The base film 8 used in the present invention needs to have a thickness of 3 to 200 μm. That is, when the thickness of the base film 8 exceeds 200 μm, its rigidity becomes high, and the function as a flexible functional element cannot be sufficiently exhibited. On the other hand, when the thickness of the base film is less than 3 μm, it is generally distributed. This is because it is difficult to obtain from the general-purpose film, the handling of the base film itself is difficult and the backing by the support film is difficult, and the strength of the base film itself is lowered and the strength of the element itself is lowered. In addition, when it is desired to further improve the flexibility of the flexible functional element, 3 to 25 μm is preferable, and 3 to 9 μm is more preferable. When the thickness of the base film is 25 μm or less, not only the flexibility can be improved, but also the thickness of the element itself can be reduced.

  The material of the base film 8 is translucent, and the pattern auxiliary electrode layer 9 and the transparent conductive layer 2 can be formed thereon. When the base film 8 is lined with the support film 10, the support film 10 and the slightly adhesive layer are formed. As long as they are in close contact with each other and have peelability, various plastics can be used without particular limitation. Specifically, plastics such as polyethylene terephthalate (PET), polyethylene naphthalate (PEN), nylon, polyethersulfone (PES), polycarbonate (PC), polyethylene (PE), polypropylene (PP), urethane, fluorine resin, etc. Can be used. Among these, PET film is preferable from the viewpoints of being inexpensive, excellent in strength, having both transparency and flexibility. Further, as the base film, a film reinforced with visible light transmitting inorganic and / or organic (plastic) fibers (including needle-like, rod-like, whisker fine particles) and flake-like fine particles (including plate-like) may be used. Good. A base film reinforced with fibers or flaky fine particles can have a good strength even with a thinner film.

As described above, in the film with a transparent conductive layer and the flexible dispersion type EL element of the present invention, the film with the transparent conductive layer can be peeled off at the interface with the base film 8 on the surface where the transparent conductive layer 2 is not formed. By backing the support film 10 having a slightly adhesive layer, the thickness of the base film itself can be set thin, and if the material of the base film is appropriately selected, good flexibility can be imparted to the dispersion type EL element. It is.
In addition, as a role of the support film 10 used by this invention, the function which makes it easy to handle in the manufacturing process of the flexible dispersion type | mold EL element of this invention, phosphor layer 3, the dielectric material layer 4, the back electrode layer 5, etc. Function to prevent warping (curling) of the substrate in the lamination process, function to protect during transportation / handling of the film with the transparent conductive layer and the dispersion type EL element, the transparent conductive layer 2, the phosphor layer 3, the dielectric layer 4, Function to uniformly print back electrode layer 5 and the like (generally, in screen printing, a suction stage having a large number of small-diameter holes is used, and the holes are decompressed to fix the film. However, if the film as a substrate is thin The film in the hole portion is deformed by the reduced pressure to form a dent, and the mark of the dent is generated on the screen-printed film.

Here, the support film 10 used in the present invention has a thickness of 50 μm or more, preferably 75 μm or more, and more preferably 100 μm or more. When the thickness of the support film is less than 50 μm, the rigidity of the film is lowered, handling in the manufacturing process of the dispersion type EL element, warping of the substrate (curl), phosphor layer 3, dielectric layer 4, back surface This is because problems such as printability of the electrode layer 5 are likely to occur.
In addition, the flexible dispersive EL element of the present invention is subjected to a half-cut treatment so that only the dispersive EL element portion having a predetermined shape can be peeled off from the backing film at the end of the production process. When the thickness of 10 is less than 50 μm, there arises a problem that half-cut processing cannot be performed well. The half-cut treatment is a method of cutting only the dispersion EL element portion including the base film 8 in accordance with the element shape using a mold press or the like in the dispersion EL element lined with the support film 10. However, since a part of the backing support film 10 is actually cut, the support film 10 is required to have a predetermined thickness as described above. On the other hand, the support film 10 used in the present invention preferably has a thickness of 200 μm or less. That is, when the thickness exceeds 200 μm, the support film is hard and heavy and difficult to handle, and at the same time, it is not preferable in terms of cost.

  The support film 10 used in the present invention does not require transparency, and the material thereof is not particularly limited, and various plastics can be used. Specifically, polycarbonate (PC), polyethylene terephthalate (PET), polyethylene naphthalate (PEN), nylon, polyethersulfone (PES), polyethylene (PE), polypropylene (PP), urethane, fluororesin, polyimide ( A plastic such as PI) can be used. Among these, a PET film is preferable from the viewpoint of being inexpensive, excellent in strength, and having flexibility.

Since the support film 10 in the present invention is peeled off from the base film through the production process of the transparent conductive layer-attached film and the dispersion-type EL element while being in close contact with the base film 8, it is generally acrylic or A silicone-based slightly adhesive layer is applied and formed. A silicone-based slightly adhesive layer is preferable in that it has excellent heat resistance.
Here, the fine adhesive layer used in the present invention is a force required for peeling per unit length in the peeled portion in relation to the base film 8 in peel strength (T-type peel test [tensile speed = 300 mm / min]). ) Is 1 to 15 g / cm, preferably 2 to 10 g / cm, more preferably 2 to 6 g / cm. That is, when the peel strength is less than 1 g / cm, even if the support film 10 and the base film 8 are bonded, it is not preferable because the film easily peels off in the manufacturing process of the film with a transparent conductive layer and the dispersion type EL element. If it exceeds 15 g / cm, the support film 10 and the base film 8 are difficult to peel off, so that the flexible dispersive EL element is difficult to peel off from the support film 10, and the workability of the EL element peeling process deteriorates, forcibly peeling off. This is because there is a high risk that the element will be elongated due to the above, deterioration of the transparent conductive layer 2 (cracking, etc.), partial adhesion of the slightly adhesive layer to the surface of the base film 8 and the like.

  By the way, as described later, the flexible dispersion type EL element of the present invention is produced through several heat treatment steps (usually about 120 to 140 ° C.) with respect to the film with a transparent conductive layer, and thus undergoes these treatment steps. It is necessary to maintain the above-mentioned peel strength afterwards, and for this purpose, the material of the slightly adhesive layer is required to have heat resistance. Moreover, since an ultraviolet curing process may be applied at the time of manufacture of a film with a transparent conductive layer, the ultraviolet-ray resistance is also required for the material of the slightly adhesion layer in that case.

As described above, the flexible dispersion-type EL element of the present invention is manufactured through several heat treatment steps for the transparent conductive layer-coated film. The dimensional change rate (heat shrinkage rate) in both the direction (MD) and the horizontal direction (TD) is preferably 0.3% or less (more preferably 0.15% or less, still more preferably 0.1% or less). . That is, when the dimensional change rate in either the vertical direction (MD) or the horizontal direction (TD) exceeds 0.3%, the phosphor layer 3, the dielectric layer 4, and the back electrode layer 5 are formed on the film with a transparent conductive layer. In each laminating process in which each layer is formed by sequentially pattern-printing, drying, and heat-curing each layer-forming paste, a dimensional change (shrinkage) occurs at each heat-curing process, resulting in print misalignment. The magnitude of the deviation exceeds the allowable range in the manufacture of the dispersion type EL element, which is not preferable. Therefore, it goes without saying that even if the dimensional change rate of the film with a transparent conductive layer is 0% (which means that there is no film), it is within the scope of the technical idea of the present invention.
In a plastic film, the dimensional change rate associated with heat treatment generally indicates a shrinkage rate. For example, in a biaxially stretched PET film, the shrinkage rate in the machine direction (MD) of the heat treatment is the shrinkage in the transverse direction (TD). The value is several times larger than the rate.

  As a method of reducing the dimensional change rate, a method using a heat-shrinkable low heat shrink type support film or a base film, a method of pre-shrinking a base film backed with a support film, or transparent conductive Although the method etc. which heat-shrink with the film with a layer can be considered, it is not limited to these. If these methods are appropriately applied, it becomes possible to reduce the dimensional change rate of the film with the transparent conductive layer during the heat treatment step, and at the same time, the transparent conductive layer resulting from the difference in the dimensional change rate between the support film 10 and the base film 8. It is also possible to suppress warpage (curl) in the flexible dispersed EL element lined with the attached film or the support film 10.

Next, the manufacturing method of the film with a transparent conductive layer of this invention is demonstrated.
First, a thin film having a thickness of 0.02 to 0.2 μm mainly composed of metal is formed on the entire surface of the base film 8 having a thickness of 3 to 200 μm by a physical film forming method such as a sputtering method or a vacuum evaporation method. Next, patterning is performed on the thin film by applying a photolithography process (photo patterning in which a photoresist is applied, formed, exposed and developed, and then etched using an etchant). As another method, a coating solution for forming an auxiliary electrode layer mainly composed of metal nanoparticles such as silver colloid ink may be printed on the base film by pattern printing such as ink jet printing or screen printing.

The formation of the transparent conductive layer 2 mainly composed of conductive oxide fine particles and a binder matrix on the base film 8 having the pattern auxiliary electrode layer is performed using the formation method described in Patent Documents 2 to 6 below. Can be done as follows.
First, a coating solution for forming a transparent conductive layer in which conductive oxide fine particles are dispersed in a solvent containing a binder component is applied and dried on the base film 8 and the pattern auxiliary electrode layer 9 formed thereon. After forming the coating layer, the base film 8 is compressed together, and then the binder component of the compression-treated coating layer is cured. When the base film 8 lined with the support film 10 is used, the coating layer is compressed together with the base film 8 lined with the support film 10.
The thickness of the transparent conductive layer 2 is set to 2 to 10 times the thickness of the pattern auxiliary electrode layer 9 (0.02 to 0.2 μm), and the thickness of the base film 8 ( 3 to 200 μm), the pressure during the compression treatment can be applied uniformly to the transparent conductive layer 2 even if the pattern auxiliary electrode layer 9 is present.

Here, the compression process will be described.
When the compression treatment is performed on the base film 8 and the pattern auxiliary electrode layer 9 on which the coating layer is formed, the packing density of the conductive fine particles in the transparent conductive layer 2 is increased, so that the scattering of light is reduced and the film optics is reduced. Not only can the characteristics be improved, but the conductivity can be greatly increased.
As the compression treatment, for example, the base film 8 on which the coating liquid for forming the transparent conductive layer is coated and dried may be rolled with a hard chrome-plated metal roll. In this case, the rolling pressure of the metal roll is a linear pressure: 29 .4 to 490 N / mm (30 to 500 kgf / cm) is preferable, and 98 to 294 N / mm (100 to 300 kgf / cm) is more preferable. That is, when the linear pressure is less than 29.4 N / mm (30 kgf / cm), the effect of improving the resistance value of the transparent conductive layer by the rolling treatment is insufficient. On the other hand, when the linear pressure exceeds 490 N / mm (500 kgf / cm) This is because the base film and the support film may be distorted at the same time as the rolling equipment is enlarged.
The rolling pressure per unit area (N / mm ² ) in the rolling process of the metal roll is the nip width of the linear pressure (the width of the area in which the transparent conductive layer is crushed by the metal roll at the contact portion between the metal roll and the transparent conductive layer). The nip width is about 0.7 to 2 mm if the roll diameter is about 150 mm, although it depends on the diameter and linear pressure of the metal roll. In the present invention, since the base film 8 lined with the support film 10 is used, even if the extremely thin base film 8 is subjected to a rolling treatment, the base film 8 can be effectively prevented from being distorted or wrinkled. Furthermore, in the rolling process using a hard chrome-plated metal roll, the surface of the transparent conductive layer 2 obtained after the rolling process can be made extremely smooth by using a mirror roll having extremely small irregularities on the surface of the metal roll. This is because even if the coating layer obtained by applying the coating liquid for forming a transparent conductive film has a convex portion, the convex portion can be physically flattened by a rolling process using the metal roll. When the smoothness of the surface of the transparent conductive layer 2 is good, the above-mentioned various functional elements have the effect of preventing the occurrence of short-circuits between electrodes and element defects, which is very preferable.

  The base film 8 may be preliminarily subjected to easy adhesion treatment, specifically plasma treatment, corona discharge treatment, short wavelength ultraviolet irradiation treatment, etc., in order to increase the adhesion with the transparent conductive layer 2. it can.

  The conductive oxide fine particles applied to the coating liquid for forming a transparent conductive layer used in the present invention are conductive oxide fine particles mainly containing at least one of indium oxide, tin oxide, and zinc oxide. For example, indium tin oxide (ITO) fine particles, indium zinc oxide (IZO) fine particles, indium-tungsten oxide (IWO) fine particles, indium-titanium oxide (ITiO) fine particles, indium zirconium oxide fine particles, tin antimony Examples include oxide (ATO) fine particles, fluorine tin oxide (FTO) fine particles, aluminum zinc oxide (AZO) fine particles, gallium zinc oxide (GZO) fine particles, and the like as long as they have transparency and conductivity. Well, it is not limited to these. However, among them, ITO has the highest characteristics and is preferable.

  The average particle diameter of the conductive oxide fine particles used in the present invention is preferably 1 to 500 nm, and more preferably 5 to 100 nm. That is, when the average particle size is less than 1 nm, it becomes difficult to produce a coating liquid for forming a transparent conductive layer, and the resistance value of the obtained transparent conductive layer is increased. This is because the conductive oxide fine particles are liable to settle and become difficult to handle, and at the same time, it is difficult to simultaneously achieve high transmittance and low resistance in the transparent conductive layer. In addition, the average particle diameter of the said conductive oxide fine particle has shown the value observed with the transmission electron microscope (TEM).

  Further, the binder component of the coating liquid for forming the transparent conductive layer has a function of bonding the conductive oxide fine particles to increase the conductivity and strength of the film, a function of increasing the adhesion between the base film 8 and the transparent conductive layer 2, and Solvent resistance for preventing deterioration of the transparent conductive layer due to the organic solvent contained in various printing pastes used for forming the phosphor layer 3, the dielectric layer 4, the back electrode layer 5 and the like in the manufacturing process of the dispersion type EL element. It has a function to grant. As the binder, an organic and / or inorganic binder can be used, and in consideration of the film forming conditions of the transparent conductive layer, the base film to which the coating liquid for forming the transparent conductive layer is applied, so as to satisfy the above role. Can be selected as appropriate.

  As the organic binder used in the present invention, a thermoplastic resin such as an acrylic resin or a polyester resin is not necessarily applicable, but generally it is preferable to have a solvent resistance, and therefore, it should be a crosslinkable resin. It is necessary and can be selected from thermosetting resins, room temperature curable resins, ultraviolet curable resins, electron beam curable resins, and the like. For example, epoxy resins and fluororesins are used as thermosetting resins, two-part epoxy resins and urethane resins are used as room temperature curable resins, and various oligomers, monomers, and photoinitiators are used as ultraviolet curable resins. Examples of the electron beam curable resin include resins containing various oligomers and monomers.

  Moreover, as an inorganic binder used by this invention, the binder which has a silica sol, an alumina sol, a zirconia sol, a titania sol etc. as a main component can be mentioned. For example, as a silica sol, a polymer obtained by hydrolyzing an orthoalkyl silicate with water or an acid catalyst to advance dehydration condensation polymerization, or a commercially available alkyl silicate solution that has already been polymerized to a tetramer to pentamer. Furthermore, a polymer obtained by further proceeding hydrolysis and dehydration condensation polymerization can be used.

  If the dehydration condensation polymerization proceeds too much, the solution viscosity increases and eventually solidifies. Therefore, the degree of dehydration condensation polymerization is adjusted to be equal to or lower than the upper limit viscosity that can be applied on the transparent substrate. However, the degree of dehydration condensation polymerization is not particularly limited as long as it is a level equal to or lower than the above upper limit viscosity, but considering film strength, weather resistance and the like, a weight average molecular weight of about 500 to 50,000 is preferable. This alkylsilicate hydrolyzed polymer (silica sol) undergoes almost complete dehydration condensation reaction (crosslinking reaction) upon heating after application and drying of the coating solution for forming the transparent conductive layer, resulting in a hard silicate binder matrix (silicon oxide). A binder matrix containing as a main component. The dehydration-condensation reaction starts immediately after drying the film, and after a lapse of time, the conductive oxide fine particles are hardened so that they cannot move. Therefore, when an inorganic binder is used, the compression treatment is transparent. It is necessary to carry out as soon as possible after applying and drying the conductive layer forming coating solution.

  As the binder used in the present invention, an organic-inorganic hybrid binder can also be used. For example, a binder obtained by partially modifying the silica sol with an organic functional group and a binder mainly composed of various coupling agents such as a silicon coupling agent can be used.

  The transparent conductive layer using the inorganic binder or the organic-inorganic hybrid binder used in the present invention inevitably has excellent solvent resistance, but the adhesion with the base film and the flexibility of the transparent conductive layer It is necessary to select appropriately so as not to deteriorate the properties.

  The ratio of the conductive oxide fine particles and the binder component in the coating solution for forming the transparent conductive layer used in the present invention is about 7.2 (specific gravity of ITO) and 1 for the specific gravity of the conductive oxide fine particles and the binder component, respectively. Assuming about .2 (specific gravity of a normal organic resin binder), the conductive oxide fine particles: binder component = 85: 15 to 97: 3, preferably 87:13 to 95: 5 is preferred in terms of weight ratio. The reason is that when the rolling treatment of the present invention is carried out, the resistance of the transparent conductive layer becomes too high when the binder component is more than 85:15, while the strength of the transparent conductive layer is lowered when the binder component is less than 97: 3. At the same time, sufficient adhesion with the base film cannot be obtained.

Next, the manufacturing method of the coating liquid for transparent conductive layer formation used by this invention is demonstrated.
First, the conductive oxide fine particles are mixed with a solvent and, if necessary, a dispersant, and then dispersed to obtain a conductive oxide fine particle dispersion. Examples of the dispersant include various coupling agents such as a silicon coupling agent, various polymer dispersants, and various surfactants such as anionic, nonionic, and cationic types. These dispersants can be appropriately selected according to the type of conductive oxide fine particles used and the dispersion treatment method. Even if no dispersant is used, a good dispersion state may be obtained depending on the combination of the conductive oxide fine particles and the solvent to be applied and the dispersion method. Since the use of a dispersant may deteriorate the resistance and weather resistance of the film, a coating liquid for forming a transparent conductive layer that does not use a dispersant is most preferable. As the dispersion treatment, general-purpose methods such as ultrasonic treatment, homogenizer, paint shaker, and bead mill can be applied.

  Then, a transparent conductive layer forming coating liquid is obtained by adding a binder component to the obtained conductive oxide fine particle dispersion and further adjusting the components such as the conductive oxide fine particle concentration and the solvent composition. Here, the binder component is added to the dispersion liquid of the conductive oxide fine particles, but it may be added in advance before the step of dispersing the conductive oxide fine particles, and there is no particular limitation. What is necessary is just to set an electroconductive oxide fine particle density | concentration suitably according to the coating method to be used.

  There is no restriction | limiting in particular as a solvent used for the said coating liquid for transparent conductive layer formation, According to the coating method, film forming conditions, and the material of a base film, it can select suitably. For example, water, methanol (MA), ethanol (EA), 1-propanol (NPA), isopropanol (IPA), butanol, pentanol, benzyl alcohol, diacetone alcohol (DAA) and other alcohol solvents, acetone, methyl ethyl ketone ( MEK), methyl propyl ketone, methyl isobutyl ketone (MIBK), ketone solvents such as cyclohexanone and isophorone, ester solvents such as ethyl acetate, butyl acetate and methyl lactate, ethylene glycol monomethyl ether (MCS), ethylene glycol monoethyl ether (ECS), ethylene glycol isopropyl ether (IPC), propylene glycol methyl ether (PGM), propylene glycol ethyl ether (PE), propylene glycol methyl -Teracetate (PGM-AC), propylene glycol ethyl ether acetate (PE-AC), diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, diethylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether acetate, diethylene glycol monobutyl ether acetate, diethylene glycol dimethyl ether, Diethylene glycol diethyl ether, diethylene glycol dibutyl ether, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, glycol derivatives such as dipropylene glycol monobutyl ether, toluene, xylene, mesitylene, dodecyl Benzene derivatives such as benzene, formamide (FA), N-methylformamide, dimethylformamide (DMF), dimethylacetamide, dimethylsulfoxide (DMSO), N-methyl-2-pyrrolidone (NMP), γ-butyrolactone, ethylene glycol , Diethylene glycol, tetrahydrofuran (THF), chloroform and the like, but are not limited thereto.

  When manufacturing the flexible dispersion type EL device of the present invention, the transparent conductive layer forming coating solution is applied by a method such as screen printing, blade coating, wire bar coating, spray coating, roll coating, gravure printing, etc. After the coating layer is formed by applying and drying on the base film having the above, or further on the base film lined with the support film, the compression treatment is performed. The compression treatment is preferably performed by rolling a metal roll. Thereafter, the compression-treated coating layer is subjected to curing treatment such as heat treatment (dry curing, heat curing) and ultraviolet irradiation treatment (ultraviolet curing) depending on the type of the coating solution, thereby forming the transparent conductive layer 2.

  A general method is to form the phosphor layer 3, the dielectric layer 4, and the back electrode layer 5 on the transparent conductive layer 2 by screen printing or the like in sequence. Usually, the phosphor layer 3 and the dielectric layer 4 are formed. The paste for forming (printing) forming each layer of the back electrode layer 5 is sequentially applied (printed), dried and heat-cured (usually 120 to 140 ° C.). As these pastes, commercially available pastes can be used. The phosphor layer paste and the dielectric layer paste each contain phosphor particles (zinc sulfide-based fine particles), dielectric fine particles (barium titanate-based fine particles), and a binder whose main component is a high dielectric component such as fluororubber. The back electrode layer paste is dispersed in a solvent, and conductive fine particles such as carbon fine particles are dispersed in a solvent containing a thermosetting resin binder.

  Here, when each layer such as the phosphor layer 3 is screen-printed on the transparent conductive layer 2, generally, a method is used in which a suction stage having a large number of small-diameter holes is used and the holes are decompressed to fix the film. Is used. If the base film is thin, the film in the hole portion is deformed due to decompression, resulting in a dent, and a problem occurs in which the dent is left on the screen-printed film. Since the support film 10 having sufficient strength is sometimes used and peeled off after the dispersion type EL element is formed, the above problem can be prevented.

  The transparent conductive layer 2, the phosphor layer 3, the dielectric layer 4, and the back electrode layer 5 constitute the main part of the dispersion type EL element. In an actual dispersion type EL element, the transparent conductive layer 2 Current collecting electrode (formed with silver paste), lead electrode for back electrode layer 5 (formed with silver paste), insulating protective coating (formed with insulating paste) for preventing short circuit between electrodes, electric shock, etc. are further formed. .

  Furthermore, the manufacturing method of the flexible functional element of any one of the liquid crystal display element, the organic EL element, the electronic paper element, and the touch panel element according to the present invention is similar to the manufacturing method of the dispersion type EL element. When each of the functional elements is formed on the transparent conductive layer 2 of the film with a conductive layer and the support film 10 having a slightly adhesive layer is lined with the base film 8, the support film 10 is It can be carried out by peeling off at the interface of the slightly adhesive layer.

Various flexible functional elements such as a dispersion type EL element according to the present invention are excellent in flexibility because the thickness of the base film is thin and flexible, and among them, the flexible dispersion type EL element is a mobile phone, a remote control, and the like. It can be applied as a light emitting element incorporated in a key input component of a device such as a controller or a portable information terminal.
[Example]

  Examples of the present invention will be specifically described below, but the present invention is not limited to these examples. Further, “%” in the text indicates “% by weight”, and “part” indicates “part by weight”.

  36 g of granular ITO fine particles having an average particle size of 0.04 μm (trade name: FS-21, manufactured by Dowa Mining Co., Ltd.) are mixed with 60 g of cyclohexanone as a solvent and a small amount of a polymer dispersant, and after dispersion treatment, urethane acrylate 3.8 g of an ultraviolet curable resin binder and 0.2 g of a photoinitiator (Darocur 1173) were added and stirred well to obtain a coating liquid for forming a transparent conductive layer in which ITO fine particles having an average dispersed particle diameter of 140 nm were dispersed.

  First, prior to the production of a film with a transparent conductive layer, a heat shrink treatment (150) of a base film (PET: thickness 25 μm) lined with a support film (PET: thickness 100 μm) through a heat-resistant silicone fine adhesive layer (150 C. x 10 minutes, tension free). Thereafter, metal aluminum having a thickness of about 0.1 μm was formed on the entire surface of the base film by vapor deposition. The surface resistance value of the metal aluminum layer was about 1Ω / □. Subsequently, a positive photoresist was applied onto the metal aluminum layer and dried to form a film, and then the lattice pattern shown in FIG. 4 (line width = 20 μm, lattice hole size: 380 μm square, aperture ratio = 90.3). %)) And developed with an alkali solution to finally form the lattice-like resist film. Then, the portion of the metal aluminum layer where the resist film is not formed is removed by etching with a phosphoric acid-nitric acid-based etchant, the resist is further removed, and the pattern auxiliary electrode layer comprising a lattice-like metal aluminum layer on the base film Formed.

The transparent conductive layer forming coating solution is wire bar coated (wire diameter: 0.05 mm) on the base film on which the pattern auxiliary electrode layer is formed, dried at 60 ° C. for 1 minute, and then hard chrome having a diameter of 100 mm. Rolling treatment with a plated metal roll (linear pressure: 200 kgf / cm = 196 N / mm, nip width: 0.9 mm), and further curing of the binder component with high-pressure mercury lamp (in nitrogen, 100 mW / cm 2 × 2 seconds) And forming a transparent conductive layer (thickness: about 0.3 μm) composed of ITO fine particles and a binder densely packed on the base film and the pattern auxiliary electrode layer, and supporting film / base film / pattern auxiliary electrode The film with a transparent conductive layer which concerns on Example 1 which consists of a layer and a transparent conductive layer was obtained.
The peel strength between the support film and the base film of the film with a transparent conductive layer was 2.4 g / cm. Here, the peel strength is T-type peel strength (the base film is subjected to T-peel at a tensile speed of 300 mm / min). In addition, the dimensional change rate (heat shrinkage rate) during heating was 0.05%. In addition, the said dimensional change rate (thermal shrinkage rate) is the vertical direction (MD) and horizontal direction (TD) of the film which calculated | required heat processing (150 degreeC x 30 minutes) the film with a transparent conductive layer which concerns on a present Example. Among the dimensional change rates (shrinkage rates), the dimensional change rate (shrinkage rate) in the longitudinal direction (MD) having a large value is shown.

  The film characteristics of the transparent conductive layer were visible light transmittance: 88.5%, haze value: 1.9%, and surface resistance value: about 20Ω / □.

  In addition, the transmittance | permeability and haze value of the said transparent conductive layer are values only of a pattern auxiliary electrode layer and a transparent conductive layer, and are calculated | required by the following formulas 1 and 2, respectively.

[Calculation Formula 1]
Transmittance (%) of transparent conductive layer = [(Transmittance measured with pattern auxiliary electrode layer and base film backed by transparent conductive layer and support film) / Transmittance of base film backed by support film] × 100

[Calculation Formula 2]
Haze value of transparent conductive layer (%) = (Haze value measured with pattern auxiliary electrode layer and transparent conductive layer and base film backed by support film) − (Haze value of base film backed by support film)

  The surface resistance of the transparent conductive layer was measured using a surface resistance meter Loresta AP (MCP-T400) manufactured by Mitsubishi Chemical Corporation. The haze value and visible light transmittance were measured using a haze meter (HR-200) manufactured by Murakami Color Research Laboratory.

  Next, a 200-mesh phosphor paste (DuPont 7154J) in which zinc sulfide particles, which are phosphors, are dispersed in a resin solution containing a fluoropolymer as a main component on the transparent conductive layer of the film with the transparent conductive layer, is prepared. Screen printing to a size of 40 × 29 cm using a polyester screen, drying at 120 ° C. for 30 minutes to form a phosphor layer, and in a resin solution containing a fluoropolymer as a main component on the phosphor layer A dielectric paste (made by DuPont, 7153) in which barium titanate particles are dispersed is screen-printed to a size of 40 × 29 cm using a 200 mesh polyester screen and dried (120 ° C. × 30 minutes). Repeatedly, a dielectric layer was formed. Subsequently, a carbon conductive paste (FEC-198, manufactured by Fujikura Kasei Co., Ltd., FEC-198) is screen-printed on a 39-mesh polyester screen to a size of 39 × 28 cm on the dielectric layer, and dried at 130 ° C. for 30 minutes to form a back electrode layer. Formed.

  Thereafter, an Ag lead wire for voltage application is formed on one side of the transparent conductive layer (an end portion which is not a light emitting portion) and a part of the back electrode layer using a silver conductive paste, and the support film is peeled off. Dispersion type EL elements (base film / pattern auxiliary electrode layer and transparent conductive layer / phosphor layer / dielectric layer / back electrode layer) were obtained as flexible functional elements. In order to prevent short-circuit between electrodes, electric shock, etc., an insulating layer is formed using an insulating paste (XB-101G, manufactured by Fujikura Kasei Co., Ltd.) as an insulating protective coating for the transparent conductive layer and the back electrode layer as necessary. did.

In the production process of the dispersion type EL element, the base film was easily peeled off at the interface with the support film. The peel strength between the support film and the base film was 3.1 g / cm. When a voltage of 100 V and 400 Hz was applied between the voltage application lead wires of this flexible dispersion type EL element, the dispersion type EL element emitted light uniformly, and its luminance was measured to be 48.5 Cd / m ² . The luminance was measured with a luminance meter (trade name: BM-9 manufactured by Topcon Corporation).

  In Example 1, the transparent conductive layer forming coating solution is composed of ITO fine particles and a binder that are densely packed on a base film backed by a wire bar coating (wire diameter: 0.075 mm). A transparent conductive layer (film thickness: about 0.5 μm) is formed, the peel strength between the support film and the base film is 2.4 g / cm, and the dimensional change rate (heat shrinkage rate) is 0.05% when heated. Except for obtaining a film with a transparent conductive layer according to Example 2 having a transparent conductive layer having a light transmittance of 95.1%, a haze value of 1.4%, and a surface resistance value of 1500 Ω / □, It carried out similarly and the flexible dispersion type | mold EL element was obtained.

Also in the manufacturing process of the flexible dispersion type EL element in this example, the base film was easily peeled off at the interface with the support film. The peel strength between the support film and the base film was 3.0 g / cm. When a voltage of 100 V and 400 Hz was applied between the voltage application lead wires of this flexible dispersion type EL element, the dispersion type EL element emitted light uniformly, and its luminance was measured to be 53 Cd / m ² .

  A base film (PET: thickness 12 μm) lined with a support film (PET: thickness 125 μm) through a heat-resistant silicone slightly adhesive layer was used after being subjected to heat shrinkage treatment (150 ° C. × 15 minutes, tension free). Except for the above, the same procedure as in Example 2 was performed, and the peel strength between the support film and the base film was 2.3 g / cm. A film with a transparent conductive layer having a transparent conductive layer of 0.0%, haze value: 1.6%, and surface resistance value: 1500Ω / □ was obtained. Moreover, it carried out similarly to Example 2 except having used this film with a transparent conductive layer, and obtained the flexible dispersion type | mold EL element.

Also in the manufacturing process of the flexible dispersion type EL element in this example, the base film was easily peeled off at the interface with the support film. The peel strength between the support film and the base film was 3.2 g / cm. When a voltage of 100 V and 400 Hz was applied between the voltage application lead wires of this flexible dispersion type EL element, the dispersion type EL element emitted light uniformly, and its luminance was measured to be 53 Cd / m ² .
(Comparative Example 1)

  In Example 1, without forming the pattern auxiliary electrode layer, a transparent conductive layer (thickness: about 0.3 μm) composed of ITO fine particles and a binder closely packed on a 25 μm-thick base film is formed. And the film with a transparent conductive layer which consists of a support film / base film / transparent conductive layer was obtained. The peel strength between the support film and the base film was 2.4 g / cm. In addition, the dimensional change rate (heat shrinkage rate) during heating was 0.05%.

  The film properties of the obtained transparent conductive layer were visible light transmittance: 97.8%, haze value: 1.8%, and surface resistance value: 5 KΩ / □. In addition, since the surface resistance value tends to temporarily decrease immediately after curing due to the influence of ultraviolet irradiation during binder curing, the surface resistance value is measured one day after the formation of the transparent conductive layer.

  And it carried out similarly to Example 1 except having used the said film with a transparent conductive layer (surface resistance value: 5Kohm / square), and obtained the dispersion-type EL element as a flexible functional element.

In the case of this comparative example, in the production process of the dispersion-type EL element, the base film could be easily peeled at the interface with the support film, and the peel strength between the support film and the base film was 3.1 g / cm. However, when a voltage of 100 V and 400 Hz is applied between the voltage application lead wires of this distributed EL element, the light emission is non-uniform, and only the vicinity of one side where the voltage application Ag lead is provided emits light. The brightness of the portion was significantly reduced.
(Comparative Example 2)

  In Example 1, instead of the PET film having the pattern auxiliary electrode layer, the densely packed ITO fine particles and the transparent conductive layer composed of the binder, a PET film (base film) having a thickness of 125 μm by sputtering. Except for using the commercially available sputtering ITO film (visible light transmittance: 92.0%, haze value: 0%, surface resistance value: 100Ω / □) formed on the top, it is performed in the same manner as in Example 1, A dispersion type EL element (PET film / sputtering ITO layer / phosphor layer / dielectric layer / back electrode layer) was obtained. In addition, the dimensional change rate (thermal shrinkage rate) at the time of the heating of the said sputtering ITO film was 0.3%.

When a voltage of 100 V and 400 Hz was applied between the voltage application lead wires of the dispersion type EL element, the dispersion type EL element emitted light uniformly, and its luminance was measured to be 55 Cd / m ² .

  In addition, the transmittance | permeability and haze value of the said sputtering ITO film are values only of an ITO layer, and are calculated | required by the following formulas 1 and 2, respectively.

[Calculation Formula 1]
Transmittance of ITO layer (%) = [(transmittance measured for the base film on which the ITO layer is formed) / transmittance of base film] × 100

[Calculation Formula 2]
Haze value of transparent conductive layer (%) = (Haze value measured with base film on which ITO layer is formed) − (Haze value of base film)

  Next, in order to evaluate the change with time of the resistance value of the film with a transparent conductive layer, the film with a transparent conductive layer according to Example 1 was left in an environment of 25 ° C. and 50 to 60% RH for 3 months to obtain surface resistance. A change in value and a change in appearance were observed, but no change was observed at all. On the other hand, when the film with the transparent conductive layer of Comparative Example 1 was left under the same conditions, the conductivity deteriorated up to about 10 times the initial resistance value.

  In addition, in order to evaluate the flexibility of the dispersion type EL element, the dispersion type EL element according to Example 1 (with the support film peeled off) and the dispersion type EL element according to Comparative Example 2 were put on a bar having a diameter of 5 mm and its light emitting surface. Were wound once each so as to be inside and outside, respectively, voltage of 100 V and 400 Hz was applied between the voltage application leads of the dispersion type EL element, and the light emission state of the element was observed. As a result, in Example 1, no change was observed in the light emission state, but in Comparative Example 2, a crack was generated in the sputtering ITO layer, and light was not emitted in most parts. Comparative Example 1 was not evaluated because the light emission was originally non-uniform.

  Furthermore, in order to evaluate the solvent resistance of the dispersion type EL element, in the film with a transparent conductive layer according to Example 1, the transparent conductive layer surface was rubbed 10 times with a cotton swab dipped in acetone, and the appearance change was observed. There was no change. In addition, a dispersion type EL device was manufactured using the transparent conductive layer thus evaluated, and a voltage of 100 V and 400 Hz was applied between the voltage application leads, and the light emission state of the device was observed. Luminescence was uniform including the part, and no influence of acetone was observed.

  The film with a transparent conductive layer of the present invention has excellent flexibility and high transparency and conductivity as compared with various functional elements such as a conventional sputtering ITO film and a dispersion type EL element using the film. In addition, the conductivity is stable (a change with time is suppressed), and according to the manufacturing method, various flexible functionalities in which a film with a transparent conductive layer and a dispersion type EL element using the same are incorporated. An element can be provided at low cost. Furthermore, when the film with a transparent conductive layer is applied to a dispersion-type EL element, the transparent conductive layer has high transparency, and its resistance value is sufficiently low, so that it is a large element excellent in high luminance and light emission uniformity. Furthermore, since the change in the resistance value of the transparent conductive layer over time is suppressed, various flexible displays such as liquid crystal display elements, organic EL elements, electronic paper elements, and touch panel elements other than the dispersion type EL elements can be obtained. The effect brought about by it, such as being suitable as a transparent electrode of a functional element, is extremely large.

It is a schematic sectional drawing which shows one Example of the dispersion type EL element as a flexible functional element based on this invention. It is a schematic sectional drawing which shows the state by which the dispersion type EL element same as the above was lined with the support film. It is a schematic sectional drawing which shows one Example of the film with a transparent conductive layer in which the pattern auxiliary electrode layer and the transparent conductive layer were formed on the base film. An example of a film with a transparent conductive layer formed by a coating method on a base film so that the transparent conductive layer covers the pattern auxiliary electrode layer after forming a lattice-shaped pattern auxiliary electrode layer on the base film is shown. It is the schematic plan view seen from the transparent conductive layer side. It is sectional drawing which shows an example of the basic structure of the conventional dispersion-type EL element. It is sectional drawing which shows the other structural example of the conventional dispersion-type EL element.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Transparent plastic film 2 Transparent conductive layer 3 Phosphor layer 4 Dielectric layer 5 Back electrode layer 6 Current collecting electrode 7 Insulating protective layer 8 Base film 9 Pattern auxiliary electrode layer 10 Support film

Claims (19)

  A film with a transparent conductive layer in which a pattern auxiliary electrode layer is formed on a base film, and a transparent conductive layer is further formed on the base film and the pattern auxiliary electrode layer by a coating method, and the thickness of the base film is 3 to 3 The pattern auxiliary electrode layer is a thin film having a thickness of 0.02 to 0.2 μm whose main component is a metal, and the transparent conductive layer is 2 to 10 times as thick as the pattern auxiliary electrode layer. A film with a transparent conductive layer, comprising a conductive oxide fine particle and a binder matrix as main components and further subjected to a compression treatment.   The film with a transparent conductive layer according to claim 1, wherein the base film has a thickness of 3 to 25 μm.   3. The support film having a slightly adhesive layer that can be peeled off at the interface with the base film is lined on the surface of the film with the transparent conductive layer where the transparent conductive layer is not formed. Film with transparent conductive layer.   The peel strength between the fine adhesive layer and the base film (force required for peeling per unit length in the peeled portion) is 1 to 15 g / cm regardless of the presence or absence of the heat treatment step. The film with a transparent conductive layer according to claim 3.   The transparent conductive layer according to any one of claims 1 to 4, wherein a dimensional change rate (heat shrinkage rate) in the vertical direction and the horizontal direction of the film with the transparent conductive layer is 0.3% or less. Layered film.   The said pattern auxiliary electrode layer contains any one or more of aluminum, nickel, chromium, and silver as a main component, The transparent conductive layer attachment of any one of Claims 1-5 characterized by the above-mentioned. the film.   The film with a transparent conductive layer according to claim 1, wherein the pattern of the pattern auxiliary electrode layer has a lattice shape, a mesh shape, a honeycomb shape, a parallel line shape, or a comb shape. .   8. The transparent conductive material according to claim 1, wherein the conductive oxide fine particles contain at least one of indium oxide, tin oxide, and zinc oxide as a main component. Layered film.   The film with a transparent conductive layer according to claim 1, wherein the conductive oxide fine particles containing indium oxide as a main component are indium tin oxide fine particles.   The film with a transparent conductive layer according to claim 1, wherein the binder matrix is cross-linked and has resistance to an organic solvent.   The film with a transparent conductive layer according to claim 1, wherein the compression treatment is performed by rolling a metal roll.   The functional element in any one of a liquid crystal display element, an organic electroluminescent element, an inorganic dispersion type electroluminescent element, an electronic paper element, and a touch panel element is formed on the transparent conductive layer of the film with a transparent conductive layer according to claim 1. When the support film formed and having a slightly adhesive layer is lined with the base film, the support film is peeled and removed at the interface between the base film and the slightly adhesive layer. Sex element.   A method for producing a film with a transparent conductive layer, wherein a pattern auxiliary electrode layer and a transparent conductive layer are formed on the surface of a base film having a thickness of 3 to 200 μm, wherein the thickness of the base film is mainly composed of metal. After forming a pattern auxiliary electrode layer of 0.02 to 0.2 μm, for forming a transparent conductive layer mainly comprising conductive oxide fine particles, a binder, and a solvent on the base film and the pattern auxiliary electrode layer A coating layer is formed using a coating solution, and then the base film and the pattern auxiliary electrode layer on which the coating layer is formed are subjected to compression treatment, and then the compression-treated coating layer is cured to perform the pattern assistance. The manufacturing method of the film with a transparent conductive layer characterized by forming the transparent conductive layer which has a thickness 2-10 times the thickness of an electrode layer.   The base film is backed by a support film having a slightly adhesive layer that can be peeled off at the interface with the base film, and a pattern auxiliary electrode layer and a transparent conductive layer are sequentially provided on the surface of the base film that is not backed by the support film. It forms, The manufacturing method of the film with a transparent conductive layer of Claim 13 characterized by the above-mentioned.   The pattern auxiliary electrode layer is formed by a photolithography process (photoresist patterning and etching) on a thin film having a thickness of 0.02 to 0.2 μm mainly composed of a metal formed on a base film by a physical film formation method. The method for producing a film with a transparent conductive layer according to claim 13 or 14, wherein   The transparent conductive layer according to claim 13 or 14, wherein the pattern auxiliary electrode layer is formed by pattern printing an auxiliary electrode layer forming coating liquid mainly composed of metal nanoparticles on a base film. A manufacturing method of attached film.   The said compression process is performed by the rolling process of a metal roll, The manufacturing method of the film with a transparent conductive layer of any one of Claims 14-16 characterized by the above-mentioned.   The method for producing a film with a transparent conductive layer according to claim 17, wherein the rolling treatment has a linear pressure of 29.4 to 490 N / mm (30 to 500 kgf / cm).   A functional element of any one of a liquid crystal display element, an organic electroluminescence element, an inorganic dispersion type electroluminescence element, an electronic paper element, and a touch panel element is formed on the transparent conductive layer of the film with a transparent conductive layer according to claim 14. When the support film formed and having the slightly adhesive layer is lined with the base film, the support film is peeled and removed at the interface between the base film and the slightly adhesive layer. Device manufacturing method.