JP2001328192A - Functional film and manufacturing method therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a multilayer functional film which is prepared by a coating method and can exert various functions and which comprises a transparent conductive layer having a low electric resistance value, for instance, and a method of manufacturing the multilayer functional film at a low temperature and in a simple process by the coating method. SOLUTION: The multilayer functional film has at least two of functional layers 12, 13, 14 and 15 on a substrate 11 and at least one of the at least two functional layers is a compressed layer of functional particulates. The film has preferably at least two compressed layers of the functional particulates. In one form, at least one of the compressed layers of the functional particulates is the transparent conductive layer 12 of compressed conductive particulates.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a multilayer functional film having at least two functional layers formed on a support. The functional layer is a layer having a function, and the function means a function performed through physical and / or chemical phenomena. The functional layer includes a conductive layer, a magnetic layer, a ferromagnetic layer, a dielectric layer, a ferroelectric layer, an insulating layer, a light absorption layer, a light selective absorption layer, a reflection layer, an antireflection layer, a catalyst layer, a photocatalyst layer, Coloring layer,
Layers having various functions such as an EL light emitting layer are included.

[0002] A multi-layer functional film has a multi-layer structure in which a plurality of functional layers exhibiting different functions. By combining a plurality of functional layers, a functional film exhibiting high functions can be obtained. The multilayer functional film includes, for example, an electrochromic film, an electroluminescent film, and the like. A solar cell in which a layer having a photoelectric effect and a transparent conductive layer are combined is also included in the multilayer functional film.

When conductive fine particles are used as functional fine particles, a functional film having a transparent conductive layer can be obtained. The transparent conductive film can be used as a transparent electrode such as an electroluminescence panel electrode, an electrochromic element electrode, a liquid crystal electrode, a transparent surface heating element, and a touch panel, and can also be used as a transparent electromagnetic wave shielding film.

[0004]

2. Description of the Related Art Conventionally, functional films made of various functional materials have been produced by physical vapor deposition (PVD) such as vacuum deposition, laser ablation, sputtering, ion plating, thermal CVD, optical CVD, and the like. It is manufactured by chemical vapor deposition (CVD) such as plasma CVD. These generally require a large-scale apparatus, and some of them are not suitable for forming a large-area film.

[0005] Also, formation of a film by coating using a sol-gel method is known. The sol-gel method is also suitable for forming a large-area film, but often requires sintering the inorganic material at a high temperature after coating.

For example, a transparent conductive film is as follows. At present, transparent conductive films are mainly manufactured by a sputtering method. There are various methods of sputtering, for example, accelerated collision of inert gas ions generated by direct current or high-frequency discharge in a vacuum onto the target surface, and strike out atoms constituting the target from the surface,
This is a method of forming a film by depositing it on the substrate surface. The sputtering method is excellent in that a conductive film having a low surface electric resistance can be formed even with a relatively large area. However, there is a disadvantage that the apparatus is large and the film forming speed is low. As the area of the conductive film is further increased in the future, the size of the device will be further increased. This technically causes problems such as the necessity of increasing control accuracy, and another problem arises that manufacturing costs increase.
Further, the number of targets is increased to compensate for the low film formation speed, and the speed is increased. However, this also causes a problem in that the size of the apparatus is increased.

[0007] Production of a transparent conductive film by a coating method has also been attempted. In a conventional coating method, a conductive paint in which conductive fine particles are dispersed in a binder solution is applied on a substrate, dried, and cured to form a conductive film. The coating method has such advantages that a large-area conductive film can be easily formed, the apparatus is simple, the productivity is high, and the conductive film can be manufactured at lower cost than the sputtering method. In the coating method, the conductive fine particles come into contact with each other to form an electric path, thereby exhibiting conductivity. However, a conductive film produced by a conventional coating method has a defect that the contact is insufficient and the resulting conductive film has a high electric resistance value (poor in conductivity), and its use is limited.

As a method for producing a transparent conductive film by a conventional coating method, for example, Japanese Patent Application Laid-Open No. 9-109259 discloses a method in which a paint composed of a conductive powder and a binder resin is applied onto a transfer plastic film, dried, and dried. First step of forming a layer, pressurizing the conductive layer surface to a smooth surface (5 to 100 kg /
cm ² ), a second step of heating (70 to 180 ° C.)
A production method comprising a third step of laminating this conductive layer on a plastic film or sheet and thermocompression bonding is disclosed. In this method, a large amount of binder resin is used (in the case of inorganic conductive powder, binder 1 is used).
100 parts by weight, 100 to 500 parts by weight of conductive powder, and in the case of organic conductive powder, 0.1 to 30 parts by weight of conductive powder with respect to 100 parts by weight of binder)
A transparent conductive film having a low electric resistance cannot be obtained.

For example, Japanese Patent Application Laid-Open No. Hei 8-199096 discloses a method for forming a binder-free conductive film comprising tin-doped indium oxide (ITO) powder, a solvent, a coupling agent, and an organic or inorganic acid salt of a metal. A method is disclosed in which a paint is applied to a glass plate and fired at a temperature of 300 ° C. or higher. In this method, since no binder is used, the electric resistance of the conductive film is reduced. But 300 ° C
Since it is necessary to perform the firing step at the above temperature, it is difficult to form a conductive film on a support such as a resin film. That is, the resin film is melted, carbonized, or burned by the high temperature. Depending on the type of resin film, for example, polyethylene terephthalate (P
For ET) films, a temperature of 130 ° C. would be the limit.

As a method other than the coating method, see Japanese Patent Application Laid-Open No. 6-1
Japanese Patent No. 3785 discloses a powder compression layer in which at least a part, preferably all of the voids of a skeleton structure composed of a conductive substance (metal or alloy) powder is filled with a resin, and a resin under the powder compressed layer. A conductive coating comprising a layer is disclosed.
The production method will be described by taking a case where a film is formed on a plate material as an example. According to the publication, first, a resin, a powdery substance (metal or alloy) and a plate material to be processed are vibrated or agitated in a container together with a film forming medium (steel balls having a diameter of several mm). A resin layer is formed on the surface. Subsequently, the powder material is captured and fixed to the resin layer by the adhesive force of the resin layer. Further, the vibrating or agitating film-forming medium exerts a striking force on the vibrating or agitating powder material to form a powder compaction layer. A significant amount of resin is required to obtain the effect of fixing the powder compression layer. Further, the production method is more complicated than the coating method.

Japanese Patent Application Laid-Open No. 7-38 is an example of a multilayer functional film.
No. 128, a transparent insulating film is formed on a transparent conductive film formed on a transparent insulating substrate, and a group I is formed on the transparent insulating film.
There is disclosed a solar cell in which a chalcopallite structure semiconductor comprising Group III and Group IV is formed, and a metal electrode is formed on the semiconductor. It is disclosed that indium oxide, tin oxide, and zinc oxide can be used as the transparent conductive film, and zinc oxide, titanium oxide, and aluminum oxide can be used as the transparent insulator film. The semiconductor film and the metal electrode are formed by vapor deposition.

An example of the multilayer functional film is an electroluminescence (EL) element. For example, the distributed DC operation EL has a multilayer structure in which an EL light emitting layer is formed on a transparent conductive film, and a back electrode is formed on the EL light emitting layer. As described above, the electroluminescence element has the E
It has a multilayer structure including an L light emitting layer.

An example of the multilayer functional film is an electrochromic (EC) device. The electrochromic element has, for example, a structure in which a first color-forming layer, a dielectric layer, a second color-forming layer, and a transparent conductive film are formed in this order on a transparent conductive film. The first coloring layer and the second coloring layer are layers having electrochromism. As described above, the electrochromic element has a multilayer structure including a layer having electrochromism.

In the production of these multilayer functional films,
The sputtering method is mainly used. A method of sintering an inorganic material at a high temperature has also been proposed. However, these production methods have various problems as described above.

[0015]

From such a background,
A large-area functional film can be easily formed on a support, and various functions can be expressed while taking advantage of the application method that the functional film can be manufactured at a low cost with a simple apparatus and high productivity. It is desired to develop a method for obtaining a multilayer functional film, for example, a multilayer functional film including a transparent conductive layer having a low electric resistance value in a low-temperature process.

Accordingly, an object of the present invention is to provide a multilayer functional film which can exhibit various functions by a coating method, for example, a multilayer functional film including a transparent conductive layer having a low electric resistance value. Another object of the present invention is to provide a method for easily producing the multilayer functional film at a low temperature by a coating method.

[0017]

Means for Solving the Problems Conventionally, in a coating method,
If a large amount of binder resin is not used, the functional layer cannot be formed, or if no binder resin is used,
It was thought that a functional layer would not be obtained without sintering the functional material at a high temperature. Regarding the conductive film, the conductive layer cannot be formed unless a large amount of the binder resin is used, or if the binder resin is not used, the conductive layer cannot be obtained unless the conductive material is sintered at a high temperature. Was considered.

However, as a result of intensive studies, the present inventor has found that
Surprisingly, it was found that a functional layer having mechanical strength and exhibiting various functions can be obtained by compression without using a large amount of binder resin and without firing at a high temperature. The inventors have found that a multilayer functional film can be obtained by combining a plurality of functional layers having different functions into a multilayer structure, and have reached the present invention.

The present invention provides a functional membrane having at least two functional layers on a support, wherein at least one of the at least two functional layers is a compressed layer of functional fine particles. There is a functional film. In the at least two functional layers, the two layers in contact with each other have different compositions. As a result, a complex function is exhibited.

In the functional film of the present invention, at least 2
It is preferable to have a compressed layer of the functional fine particles in a layer. Although it depends on the use of the multilayer functional film, in the functional film of the present invention, it is also preferable that at least one of the compressed layers of the functional fine particles is a compressed layer of conductive fine particles. The compressed layer of the conductive fine particles is preferably a transparent conductive layer. The functional material of each layer is selected according to the application of the multilayer functional film.

In the functional film according to the present invention, the compressed layer of the functional fine particles may be a functional fine particle-containing layer formed by applying a liquid in which the functional fine particles are dispersed on a support or a functional layer and drying. Obtained by compression. In the functional film of the present invention, the compressed layer of the functional fine particles has a thickness of 44 N / m.
It is preferably obtained by compressing with a compression force of m ² or more.

According to the present invention, there is provided a functional membrane having at least two functional layers on a support, wherein at least one of the at least two functional layers is a compressed layer of functional fine particles. A method in which a liquid in which functional fine particles are dispersed is coated on a support or a functional layer, and dried to form a functional fine particle-containing layer. A method for producing a functional film, comprising forming a compressed layer of fine particles.

One embodiment of the production method of the present invention is a method for producing a functional film having at least two compressed layers of functional fine particles which are in contact with each other on a support. Coating and drying on a support to form a first functional fine particle-containing layer, and then compressing the first functional fine particle-containing layer to form a first compressed layer of functional fine particles, A liquid in which functional fine particles different from the functional fine particles are dispersed is coated on the formed first compressed layer, and dried,
Forming a second functional fine particle-containing layer and then compressing the second functional fine particle-containing layer to form a second compressed layer of functional fine particles.

One embodiment of the production method of the present invention is a method for producing a functional film having at least two compressed layers of functional fine particles in contact with each other on a support, wherein a liquid in which the functional fine particles are dispersed is prepared. The first functional fine particle-containing layer is formed by coating and drying on a support to form a first functional fine particle-containing layer, and then dispersing a liquid in which functional fine particles different from the functional fine particles are dispersed. The second functional fine particle-containing layer is formed thereon by coating and drying, and then the first and second functional fine particle-containing layers are compressed to form a first compressed layer of functional fine particles and a second functional fine particle-containing layer. 2 including forming a compression layer.

One embodiment of the production method of the present invention is a method for producing a functional film having at least two compressed layers of functional fine particles which are in contact with each other on a support. A liquid in which functional fine particles different from the functional fine particles are dispersed in a wet state in which the applied layer is coated on the support and the coated layer is coated on the coated layer, and dried to obtain first and second liquids. Forming a bifunctional fine particle-containing layer, and then compressing the first and second functional fine particle-containing layers to form a first compressed layer of functional fine particles and a second compressed layer of functional fine particles. Including.

In the manufacturing method of the present invention, 44 N / mm
It is preferable to compress with a compression force of ² or more. In the production method of the present invention, it is preferable that the compression is performed at normal temperature. Since the compression can be performed at normal temperature, the effect of the present invention is great when the support is a resin film.

In the method of the present invention, the dispersion of the functional fine particles may contain a small amount of resin, but it is particularly preferable that the dispersion contains no resin. When the dispersion liquid of the functional fine particles contains a resin, the content of the resin is expressed by volume, and when the volume of the functional fine particles is 100, 25
Preferably, the volume is less than.

[0028]

BEST MODE FOR CARRYING OUT THE INVENTION The multilayer functional film of the present invention has at least two functional layers formed on a support. At least one of the at least two functional layers is a compressed layer of functional fine particles. Functional layer is not particularly limited, conductive layer, magnetic layer, ferromagnetic layer, dielectric layer, ferroelectric layer, insulating layer, light absorption layer, light selective absorption layer,
Reflective layer, anti-reflective layer, catalyst layer, photocatalytic layer, coloring layer, EL
A layer having various functions such as a light emitting layer is included.

It is preferable to form a multilayer structure by combining a plurality of functional layers having different functions according to the purpose and application of the multilayer functional film. By combining multiple functional layers,
For example, a multilayer functional film for a solar cell, an electroluminescence element, an electrochromic element, or the like can be obtained.

Specifically, for a solar cell, as shown in FIG. 1, as viewed from the substrate side, a transparent insulator substrate (11), a transparent conductive layer (12), a transparent insulator layer (13), Group I, Group III, Group IV chalcopallite structure semiconductor layer (14), metal electrode (15)
Is exemplified. For a distributed DC operation electroluminescent element, a glass substrate (21), a transparent conductive layer (22),
An example is a multilayer structure including an L light emitting layer (23) and a back electrode (24). As for the transmission type electrochromic device, FIG.
Referring to FIG. 5, a multilayer structure including a transparent conductive layer (31), a first color-forming layer (32), a dielectric layer (33), a second color-forming layer (34), and a transparent conductive layer (35), as viewed from the incident light side. The structure is exemplified. Other than these, various multilayer structures corresponding to various applications can be considered.

In the present invention, functional fine particles corresponding to the desired functional compressed layer are used. The functional fine particles are not particularly limited, and mainly inorganic fine particles having a cohesive force are used. In the production of any functional layer, by applying the method of the present invention, a functional coating film having sufficient mechanical strength can be obtained, and a binder in a conventional coating method using a large amount of a binder resin. The adverse effects of the resin can be eliminated. As a result, the intended function is further improved.

For example, in the case of a transparent conductive layer, tin oxide, indium oxide, zinc oxide, cadmium oxide, antimony-doped tin oxide (ATO), fluorine-doped tin oxide (FTO), tin-doped indium oxide (ITO), aluminum Conductive inorganic fine particles such as doped zinc oxide (AZO) are used. Alternatively, organic conductive fine particles may be used. By applying the present manufacturing method, excellent conductivity can be obtained.

Here, "transparent" means that visible light is transmitted. Regarding the degree of light scattering, the required level differs depending on the use of the multilayer functional film. In the present invention, those having scattering which is generally called translucent are also included.

In the case of a ferromagnetic layer, γ-Fe ₂ O
₃ , iron oxide-based magnetic powders such as Fe ₃ O ₄ , Co—FeOx, and Ba ferrite, α-Fe, Fe—Co, Fe—N
i, a ferromagnetic alloy powder containing a ferromagnetic metal element such as Fe-Co-Ni, Co, or Co-Ni as a main component is used.
By applying this manufacturing method, the saturation magnetic flux density of the magnetic coating film is improved.

In the case of a dielectric layer or a ferroelectric layer,
Magnesium titanate, barium titanate, strontium titanate, lead titanate, lead zirconate titanate (PZT), lead zirconate, lanthanum-added lead zirconate titanate (PLZT), magnesium silicate Fine particles of a dielectric or ferroelectric material such as a system and a lead-containing perovskite compound are used. By applying the present manufacturing method, the dielectric characteristics or the ferroelectric characteristics can be improved.

In the case of a metal oxide layer exhibiting various functions, iron oxide (Fe ₂ O ₃ ), silicon oxide (SiO ₂ )
₂ ), aluminum oxide (Al ₂ O ₃ ), titanium dioxide (TiO ₂ ), titanium oxide (TiO), zinc oxide (Zn)
Fine particles of metal oxides such as O), zirconium oxide (ZrO ₂ ), and tungsten oxide (WO ₃ ) are used. By applying the present manufacturing method, the filling degree of the metal oxide in the layer is increased, and each function is improved. For example, when SiO ₂ or Al ₂ O ₃ carrying a catalyst is used, a porous catalyst layer having practical strength can be obtained. When TiO ₂ is used, the photocatalytic function can be improved. In addition, WO
_{When 3} is used, an improvement in the coloring effect in the electrochromic display element can be obtained.

In the EL light emitting layer of the electroluminescent element, zinc sulfide (ZnS) fine particles are used. By applying this manufacturing method, an inexpensive electroluminescent element can be manufactured by a coating method.

The particle size of the functional fine particles cannot be unconditionally determined because it depends on the use and the shape of the particles.
It is about μm. For example, the particle size of the conductive fine particles differs depending on the degree of scattering required according to the use of the functional film, and cannot be unconditionally determined depending on the shape of the particles,
Generally, it is 10 μm or less, preferably 1.0 μm or less, more preferably 5 nm to 100 nm.

In the present invention, a liquid in which functional fine particles selected from the above-mentioned various functional fine particles are dispersed according to the function of each layer is used as a functional paint. This functional paint is applied on a support or a functional layer to be a lower layer, and dried to form a layer containing functional fine particles. Thereafter, the layer containing the functional fine particles is compressed to form a compressed layer of the functional fine particles to obtain a functional film.

The liquid in which functional fine particles such as conductive fine particles are dispersed is not particularly limited, and various known liquids can be used. For example, as a liquid, saturated hydrocarbons such as hexane, aromatic hydrocarbons such as toluene and xylene, alcohols such as methanol, ethanol, propanol and butanol, ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone and diisobutyl ketone , Ethyl acetate, esters such as butyl acetate, ethers such as tetrahydrofuran, dioxane, diethyl ether, N, N-dimethylformamide;
Examples include amides such as N-methylpyrrolidone (NMP) and N, N-dimethylacetamide, and halogenated hydrocarbons such as ethylene chloride and chlorobenzene. Among these, a liquid having polarity is preferable,
Especially alcohols such as methanol and ethanol, NMP
Those having an affinity for water, such as amides, have good dispersibility even without using a dispersant, and are suitable. These liquids can be used alone or in combination of two or more. Further, a dispersant can be used depending on the type of the liquid.

Further, water can be used as the liquid.
When water is used, the support needs to be hydrophilic. Since the resin film is usually hydrophobic, it easily repels water, and it is difficult to obtain a uniform film. When the support is a resin film, it is necessary to mix alcohol with water or to make the surface of the support hydrophilic.

The amount of the liquid used is not particularly limited as long as the dispersion of the fine particles has a viscosity suitable for coating. For example, the liquid is about 100 to 100,000 parts by weight based on 100 parts by weight of the fine particles. It may be appropriately selected according to the types of the fine particles and the liquid.

The fine particles may be dispersed in the liquid by a known dispersion technique. For example, the particles are dispersed by a sand grinder mill method. At the time of dispersion, it is also preferable to use a medium such as zirconia beads in order to loosen the aggregation of the fine particles. At the time of dispersion, care should be taken not to mix impurities such as dust.

In the present invention, the dispersion liquid of the fine particles is
It is particularly preferable that no resin is contained (that is, the amount of resin = 0). Alternatively, when a resin is contained, the content of the resin is preferably less than 25 when the volume of the functional fine particles is expressed as 100 before dispersion and the volume of the functional fine particles is 100. By using such a dispersion, the amount of the resin in the compressed layer of the functional fine particles obtained is 0 or less than 25 when the volume of the functional fine particles is 100.

In the conductive layer, if no resin is used,
The resin does not hinder contact between the conductive fine particles. Accordingly, conductivity between the conductive fine particles is ensured, and the electrical resistance of the obtained conductive layer is low. It is possible to include a resin as long as the conductivity is not impaired, but the amount is small as compared with the amount used as a binder resin in the prior art as the upper limit described above. In the prior art, strong compression was not performed, so that a large amount of binder had to be used to obtain the mechanical strength of the coating film. If the resin is used in such an amount that it plays a role as a binder, contact between the conductive fine particles is hindered by the binder, electron transfer between the fine particles is hindered, and the conductivity is reduced.

On the other hand, the resin has the effect of improving the haze of the conductive film. However, in terms of conductivity,
The resin is preferably used in a volume range of less than 25, and more preferably in a volume range of less than 20, when the volume of the conductive fine particles is expressed as 100 before dispersion and the volume of the conductive fine particles is 100. preferable. Although the effect of improving haze is reduced, it is most preferable not to use a resin from the viewpoint of conductivity.

Even in the functional layer using WO ₃ fine particles or TiO ₂ fine particles, the contact between the fine particles is not hindered by the resin unless the resin is used.
Each function is improved. As long as the contact between the fine particles is not hindered and the respective functions are not impaired, it is possible to contain a resin.
When it is set to 0, the volume is, for example, about 80 or less.

In the catalyst layer using Al ₂ O ₃ fine particles or the like, if no resin is used, the surface of the fine particles having a catalytic function is not covered with the resin. For this reason,
The function as a catalyst is improved. In the catalyst layer, the more voids inside the membrane, the more active sites as a catalyst, so from this viewpoint it is preferable to use no resin.

As described above, it is preferable not to use a resin for each functional compression layer constituting the multilayer functional film, and even if it is used, a small amount is preferable. The amount of the resin used may vary to some extent depending on the purpose of the functional layer, and may be appropriately determined.

In the present invention, the volume of the functional fine particles and the volume of the resin are not apparent volumes but true volumes. The true volume is obtained by obtaining the density using an instrument such as a pycnometer based on JIS Z 8807, and dividing the weight of the material used by the density. In this way, the amount of resin used is defined not by weight but by volume,
This is because when considering how the resin is present with respect to the functional fine particles in the functional layer obtained after compression, the reality is more reflected.

When a resin is used in the present invention, the resin is not particularly limited, and a thermoplastic resin or a polymer having rubber elasticity can be used alone or in combination of two or more. Examples of the resin, fluorine-based polymer, silicone resin, acrylic resin, polyvinyl alcohol, carboxymethyl cellulose, hydroxypropyl cellulose, regenerated cellulose diacetyl cellulose,
Examples thereof include polyvinyl chloride, polyvinylpyrrolidone, polyethylene, polypropylene, SBR, polybutadiene, and polyethylene oxide. Examples of the fluorine-based polymer include polytetrafluoroethylene, polyvinylidene fluoride (PVDF), vinylidene fluoride-ethylene trifluoride copolymer, ethylene-tetrafluoroethylene copolymer, propylene-tetrafluoroethylene copolymer, and the like. Can be Further, a fluorine-containing polymer in which hydrogen in the main chain is substituted with an alkyl group can also be used. The higher the density of the resin, the smaller the volume, even if a large weight is used, and it is easy to satisfy the above requirements.

Various additives may be added to the dispersion of the fine particles as long as the performance required for each functional layer is satisfied. For example, additives such as an ultraviolet absorber, a surfactant, and a dispersant.

The support is not particularly limited, and may be a resin film, glass, ceramics, metal, cloth,
Various materials such as paper can be used. However, in the case of glass, ceramics, and the like, it is highly likely that the glass will be broken at the time of compression in a later step, and therefore it is necessary to consider this point. The shape of the support may be a film, a foil, a mesh, a fabric, or the like.

As the support, a resin film (including a resin sheet) which does not break even when the compression force in the compression step is increased is preferable. The resin film is also preferable in that it has good adhesion of a functional fine particle layer such as conductive fine particles to the film, and is also suitable for applications in which weight reduction is required. In the present invention, a resin film can be used as a support because there is no pressurizing step at a high temperature or a firing step.

Examples of the resin film include a polyester film such as polyethylene terephthalate (PET), a polyolefin film such as polyethylene and polypropylene, a polycarbonate film, an acrylic film, a norbornene film (arton, manufactured by JSR Corporation), and the like. .

The dispersion of the functional fine particles for each functional layer is coated on the support or the functional layer as the lower layer, and dried to form a functional fine particle-containing layer. The application of the fine particle dispersion onto the support or the functional layer serving as a lower layer can be performed by a known method without any particular limitation. For example, it can be performed by a coating method such as a reverse roll method, a direct roll method, a blade method, a knife method, an extrusion nozzle method, a curtain method, a gravure roll method, a bar coat method, a dip method, a kiss coat method, and a squeeze method. Further, the dispersion liquid can be attached to the support by spraying or spraying.

The drying temperature depends on the type of liquid used for dispersion, but is preferably about 10 to 150 ° C. If the temperature is lower than 10 ° C., dew condensation of moisture in the air tends to occur, and if the temperature exceeds 150 ° C., the resin film support is deformed. At the time of drying, care is taken so that impurities do not adhere to the surface of the fine particles.

The thickness of the layer containing the functional fine particles after application and drying depends on the compression conditions in the next step and the use of each functional film such as the final conductive film, but may be about 0.1 to 10 μm.

As described above, when the functional fine particles are dispersed in a liquid, applied, and dried, it is easy to form a uniform film. When the dispersion of the fine particles is applied and dried, the fine particles form a film even when the binder is not present in the dispersion. Although the reason for forming a film without the presence of a binder is not always clear, fine particles gather together due to capillary force when the liquid is dried and the amount of liquid decreases. Furthermore, the fact that the particles are fine particles has a large specific surface area and a strong cohesive force, so it is thought that they may become a film. However, the strength of the film at this stage is weak. In the conductive layer, the resistance value is high, and the variation in the resistance value is large.

Next, the formed layer containing functional fine particles is compressed to obtain a compressed layer of functional fine particles such as conductive fine particles. The compression improves the strength of the film. That is, by compressing, the number of contact points between functional fine particles such as conductive fine particles increases, and the contact surface increases. For this reason, the strength of the coating film increases. Since the fine particles originally have a property of easily aggregating, they become a strong film by being compressed.

In the conductive layer, the strength of the coating film increases and the electrical resistance decreases. In the catalyst layer, the coating film strength is increased, and a porous film is formed because no resin is used or the amount of the resin is small. Therefore, a higher catalytic function can be obtained. In other functional layers as well, a high-strength film in which the fine particles are connected to each other can be obtained, and the amount of the fine particles per unit volume increases because no resin is used or the amount of the resin is small. Therefore, higher functions can be obtained.

The compression is preferably performed with a compression force of 44 N / mm ² or more. If the pressure is lower than 44 N / mm ² ,
The layer containing the functional fine particles cannot be sufficiently compressed, and it is difficult to obtain a functional layer having excellent functions. 135 N / mm ²
The above compression force is more preferable, and the compression force of 180 N / mm ² is even more preferable. The higher the compressive force, the higher the strength of the coating film and the better the adhesion to the support or the lower layer. In the conductive layer, a layer having more excellent conductivity is obtained, the strength of the conductive layer is improved, and the adhesion between the conductive layer and the support or the lower layer becomes strong. Since the higher the compressive force, the higher the pressure resistance of the device must be increased, a compressive force of up to 1000 N / mm ² is generally appropriate. In addition, compress at normal temperature (15-40
C.). The compression operation at a temperature near normal temperature is one of the advantages of the present invention.

The compression is not particularly limited and can be performed by a sheet press, a roll press or the like, but is preferably performed using a roll press machine. The roll press is a method of sandwiching a film to be compressed between rolls, compressing the roll, and rotating the roll. The roll press is preferably applied with a high pressure uniformly, and can be produced in a roll-to-roll manner, so that productivity is increased.

The roll temperature of the roll press is preferably room temperature. In a heated atmosphere or in a compression (hot press) in which a roll is heated, when the compression pressure is increased, a problem such as the resin film being elongated occurs. If the compression pressure is reduced to prevent the resin film of the support from stretching under heating, the mechanical strength of the coating film decreases. In the conductive layer, the mechanical strength of the coating film decreases, and the electric resistance increases.
If there is a reason to reduce the adhesion of moisture on the surface of the fine particles as much as possible, a heated atmosphere may be used to reduce the relative humidity of the atmosphere, but the temperature range is within the range where the film does not easily stretch. It is. Generally, the temperature is lower than the glass transition temperature (secondary transition temperature). The temperature may be set slightly higher than the temperature at which the required humidity is obtained in consideration of fluctuations in humidity. It is also preferable to adjust the temperature so that the roll temperature does not rise due to heat generation when continuously compressed by a roll press. If the support is made of metal, the atmosphere can be heated up to a temperature range in which the metal does not melt.

The glass transition temperature of the resin film is as follows:
It is determined by measuring dynamic viscoelasticity and refers to the temperature at which the mechanical loss of the main dispersion peaks. For example, looking at a PET film, its glass transition temperature is around 110 ° C.

The roll of the roll press machine is preferably a metal roll because a strong pressure is applied. In addition, if the roll surface is soft, fine particles may be transferred to the roll during compression. Therefore, it is preferable to treat the roll surface with a hard film.

Thus, a compressed layer of functional fine particles is formed. The thickness of the compressed layer of functional fine particles depends on the use of the multilayer functional film, but may be about 0.1 to 10 μm. Further, in order to obtain a single compressed layer having a thickness of about 10 μm, a series of operations of coating, drying, and compressing a dispersion liquid of fine particles may be repeatedly performed. Further, in the present invention, it is of course possible to form each functional layer such as a conductive layer on both surfaces of the support.

In producing a multilayer functional film having at least two compressed layers of functional fine particles in contact with each other on the support of the present invention, three production modes can be mainly used.

One mode (method A) of the production method of the present invention is as follows:
(a) A liquid in which functional fine particles are dispersed is coated on a support and dried to form a first functional fine particle-containing layer, and then the first functional fine particle-containing layer is compressed to form a first functional fine particle-containing layer. (B) Next, a liquid in which functional fine particles different from the functional fine particles are dispersed is applied onto the formed first compressed layer, dried, and contains the second functional fine particles. Forming a layer and then compressing the second functional fine particle-containing layer to form a second compressed layer of functional fine particles. In order to manufacture a multilayer functional film having three or more layers, the step (b) may be repeated a desired number of times after the formation of the second compressed layer.

One embodiment (method B) of the production method of the present invention is as follows.
(a) A liquid in which functional fine particles are dispersed is coated on a support and dried to form a first functional fine particle-containing layer. (b) Next, functional fine particles different from the functional fine particles are dispersed. Liquid
Coating and drying on the formed first functional fine particle-containing layer to form a second functional fine particle-containing layer, (c) thereafter, compressing the first and second functional fine particle-containing layers, Forming a first compressed layer of functional fine particles and a second compressed layer of functional fine particles. In order to manufacture a multilayer functional film having three or more layers, the step (b) may be repeated a desired number of times after the formation of the second functional fine particle-containing layer, and then the step (c) may be performed.

One mode (method C) of the production method of the present invention is as follows:
(a) A liquid in which functional fine particles are dispersed is coated on a support, and the coated layer is in a wet state, and a liquid in which functional fine particles different from the functional fine particles are dispersed is coated on the coating layer. Coating and drying to form first and second functional fine particle-containing layers, and (b) compressing the first and second functional fine particle-containing layers to form a first compressed layer of functional fine particles. And forming a second compressed layer of functional fine particles. In order to produce a multilayer functional film having three or more layers, in step (a), before drying, a dispersion of functional fine particles for an upper layer is further added to all of the applied lower layers in a wet state before drying. What is necessary is just to apply on the said coating layer.

In any case, when the dispersion of the functional fine particles for the upper layer is applied, the solid concentration of the upper layer dispersion is set higher to reduce the mixing at the interface between the upper and lower layers. May be.

Of course, the above-mentioned production modes (A, B and C)
It is also possible to produce a multilayer functional film of three or more layers by combining the above methods. For example, when manufacturing a multi-layer functional film composed of five layers, the first, second, and third layers are counted from the support.
The layer may be formed by the method A, and the fourth and fifth layers may be formed on the formed third layer by the method C. Various production forms are possible, and it may be appropriately determined according to the type of the intended multilayer functional film. In the multilayer functional film of the present invention, all of the constituent layers do not necessarily need to be compression layers. For example, in the case of a solar cell, the transparent conductive layer, the transparent insulator layer, and the semiconductor layer may be formed by compression, and the metal electrode may be formed by vapor deposition.

In the multilayer functional film of the present invention, the compressed layer of each layer exhibits excellent functions such as conductivity, and is formed using a small amount of resin that does not use a binder resin or does not function as a binder. Nevertheless, it has practically sufficient film strength and excellent adhesion to the support or the lower functional layer.

[0075]

EXAMPLES The present invention will be described more specifically with reference to the following examples, but the present invention is not limited to these examples.

Example 1 ITO / TiO ₂ Multilayer Functional Layer (Formation of First Layer) 100 parts by weight of ITO fine particles SUFP-HX (manufactured by Sumitomo Metal Mining Co., Ltd.) having a primary particle size of 5 to 30 nm Ethanol (300 parts by weight) was added, and the medium was dispersed as zirconia beads using a disperser. The obtained ITO
The coating solution was applied on a PET film having a thickness of 100 μm using a bar coater, and dried by sending 50 ° C. warm air.
The resulting film is hereinafter referred to as a pre-compression ITO film. The thickness of the ITO-containing coating film was 1.7 μm.

First, a preliminary experiment for confirming the compression pressure was performed. Room temperature (23 ° C.) using a roll press equipped with a pair of 140 mm-diameter metal rolls (having a roll surface subjected to hard chrome plating) without rotating the rolls and without heating the rolls The above-mentioned ITO film before compression was sandwiched and compressed. At this time, the pressure per unit length in the film width direction was 660 N / mm. Next, the pressure was released, and the length of the compressed portion in the longitudinal direction of the film was 1.9 mm. From this result, it can be said that compression was performed at a pressure of 347 N / mm ² per unit area.

Next, the same pre-compressed ITO film as that used in the preliminary experiment was sandwiched between metal rolls and compressed under the above conditions, and the rolls were rotated and compressed at a feed speed of 5 m / min. Thus, a compressed ITO film was obtained. The thickness of the ITO compression layer was 1.0 μm.

(Formation of Second Layer) The primary particle size is 30 to 70 n
900 parts by weight of ethanol was added to 100 parts by weight of the TiO ₂ fine particles of m, and the medium was dispersed as zirconia beads using a disperser. The obtained TiO ₂ coating solution was applied on the ITO compressed layer using a bar coater, and dried by sending warm air at 50 ° C. Next, compression was performed using a roll press under the same conditions as for the compression of the first layer. The thickness of the TiO ₂ compression layer was 0.5 μm. Thus, a multilayer functional layer composed of the first layer and the second layer was formed.

(90 ° Peel Test) In order to evaluate the adhesion of the multilayer functional layer to the support film and the strength of the multilayer functional layer, a 90 ° peel test was performed. This will be described with reference to FIG. In the test sample (1) on which the multilayer functional layer was formed, a double-sided tape (2) was applied to the surface of the support film (1b) opposite to the surface on which the multilayer functional layer (1a) was formed. This was cut out to a size of 25 mm × 100 mm. The test sample (1) was stuck on a stainless steel plate (3). Test sample
To prevent (1) from peeling off, both ends (25
Cellophane tape (4) was applied to the (mm side). (FIG. 4
(A)).

A cellophane tape (width 12 mm, No. 29, manufactured by Nitto Denko) was applied to the surface of the multilayer functional layer (1a) of the test sample (1).
(5) was attached so as to be parallel to the long side of the sample (1).
The sticking length of cellophane tape (5) and sample (1) is 5
It was 0 mm. The end of the cellophane tape (5) to which the cellophane tape (5) was not attached was attached to the tensiometer (6), and set so that the angle between the adhered surface of the cellophane tape (5) and the non-adhered surface (5a) was 90 degrees. The cellophane tape (5) was pulled off at a speed of 100 mm / min. At this time, the speed at which the tape (5) was peeled off and the stainless steel plate (3) to which the test sample (1) was attached
Was moved at the same speed, and the non-sticking surface (5a) of the cellophane tape (5) and the surface of the test sample (1) were always at 90 degrees. Force required for peeling off with a tensiometer (6) (F)
Was measured. (FIG. 4 (b)).

After the test, the surface of the peeled multilayer functional layer and the surface of the cellophane tape were examined. When the adhesive is present on both surfaces, the multilayer functional layer was not destroyed, but the adhesive layer of the cellophane tape was destroyed, that is, the force required to peel off the adhesive strength (F ), And the strength of the multilayer functional layer is equal to or higher than the value (F).

In this test, the upper limit of the adhesive strength was 6
Since it is N / 12 mm, what is indicated as 6 N / 12 mm in Table 1 is the case where the adhesive is present on both surfaces as described above, and the adhesion and the strength of the multilayer functional layer are 6 N / 12 mm.
mm or more. If the value is smaller than this, the adhesive layer is not present on the surface of the multilayer functional layer and the functional layer is partially adhered to the cellophane tape surface.

As a result of the 90-degree peel test, in Example 1, a force of 6 N / 12 mm was required to peel off the cellophane tape. When the coating film surface after the peel test was examined, the adhesive of the cellophane tape was adhered. When the adhesive surface of the peeled cellophane tape was examined, it was found to be adhesive. Therefore, the strength of the coating film was 6 N / 12 mm or more. The obtained multilayer functional film can be used as a solar cell.

Example 2 ITO / WO ₃ Multilayer Functional Layer (Formation of First Layer) The same procedure as in Example 1 was carried out. (Formation of Second Layer) WO ₃ having a primary particle size of 50 to 100 nm
400 parts by weight of ethanol is added to 100 parts by weight of fine particles,
The media was dispersed as zirconia beads using a disperser. The obtained coating solution was applied onto the first layer (ITO compressed layer) using a bar coater, and dried by sending warm air at 50 ° C. Next, compression was performed using a roll press under the same conditions as for the compression of the first layer. WO ₃ compression layer thickness is 0.6
μm. Thus, a multilayer functional layer composed of the first layer and the second layer was formed. A 90 degree peel test was performed. The strength of the coating film was 6 N / 12 mm or more. The obtained multilayer functional film can be used as an electrochromic (EC) device.

Example 3 ITO / WO ₃ / Ta ₂ O ₅
Multilayer Functional Layer] (Formation of First Layer and Second Layer) The same procedure as in Example 2 was performed. (Formation of Third Layer) Ta having a primary particle size of 100 to 300 nm
₂ O ₅ fine particle 100 parts by weight Ethanol 400 parts by weight was added to and dispersed by a dispersing machine media as zirconia beads. The obtained coating solution is applied to the second layer (WO ₃ compressed layer)
It was applied on the top using a bar coater and dried by sending warm air at 50 ° C. Next, compression was performed using a roll press under the same conditions as for the compression of the first layer. The thickness of the Ta ₂ O ₅ compression layer was 0.6 μm. Thus, a multilayer functional layer including the first layer, the second layer, and the third layer was formed. A 90 degree peel test was performed. The strength of the coating film was 6 N / 12 mm or more. The obtained multilayer functional film can be used as an electrochromic (EC) device.

[Example 4: ITO / ZnS multilayer functional layer] (Formation of first layer) The same procedure as in Example 1 was carried out. (Formation of the second layer) Zn having a primary particle size of 100 to 400 nm
400 parts by weight of ethanol was added to 100 parts by weight of the S fine particles, and the medium was dispersed as zirconia beads using a disperser. The obtained coating liquid is applied on the first layer (ITO compressed layer) using a bar coater, and dried by sending warm air of 50 ° C. to form a ZnS coating layer, and obtain a ZnS film before compression. Was. If the ZnS film before compression is roll-pressed as it is, ZnS may adhere to the roll.
Then, roll pressing was performed using the following film for preventing adhesion. A silicone-based hard coat material: Tosgard 510 (manufactured by GE Toshiba Silicone Co., Ltd.) is applied to a 50 μm-thick PET film, dried, and cured (100 ° C., 2 hours) to form a hard coat on the PET film. A film for preventing adhesion was prepared. The pre-compressed ZnS film and the anti-adhesion film are overlapped so that the ZnS coating layer surface and the hard coat surface are in contact with each other, the two films are sandwiched between metal rolls, and roll pressing is performed under the same conditions as the compression of the first layer. Compressed using a press. Since the hard coat was formed on the film for preventing adhesion, these two films did not adhere to each other after the roll pressing. The thickness of the ZnS compression layer was 1.0 μm. Thus, a multilayer functional layer composed of the first layer and the second layer was formed. A 90 degree peel test was performed. The strength of the coating film was 4 N / 12 mm. The obtained multilayer functional film can be used as an electroluminescence (EL) element.

[Example 5: ITO / TiO ₂ multilayer functional layer] (Coating and drying of first layer) The same ITO coating solution as used for forming the first layer in Example 1 was applied to a PET film having a thickness of 100 μm. It was applied on the top using a bar coater and dried by blowing warm air at 50 ° C. to form an ITO-containing coating film. The thickness of the coating film was 1.7 μm.

(Coating and Drying of Second Layer) Second Layer of Example 1
The same TiO used in the formation of_TwoApply the coating solution to the ITO
On the containing coating film using a bar coater,
Dry with hot air _TwoA containing coating film was formed.

(Compression of First Layer and Second Layer) The obtained film was compressed using a roll press under the same conditions as in Example 1. The thickness of the compressed ITO layer after compression is 1.0
μm, and the thickness of the TiO ₂ compression layer was 0.5 μm. Thus, a multilayer functional layer composed of the first layer and the second layer was formed. A 90 degree peel test was performed. The strength of the coating film was 6 N / 12 mm or more. The obtained multilayer functional film can be used as a solar cell.

[Example 6: ITO / TiO ₂ multilayer functional layer] (Coating and drying of first layer and second layer) As a coating liquid for the first layer, it was used in forming the first layer of Example 1. The same TiO ₂ coating solution as that used in the formation of the second layer in Example 1 was used as the second layer coating solution. 10
The coating liquid for the first layer is applied on a PET film having a thickness of 0 μm using an applicator, and while the first layer is in a wet state, the coating liquid for the second layer is applied. And dried to form an ITO-containing coating and a TiO ₂ -containing coating.

(Compression of First Layer and Second Layer) The obtained film was compressed using a roll press under the same conditions as in Example 1. The thickness of the compressed ITO layer after compression is 1.0
μm, and the thickness of the TiO ₂ compression layer was 0.5 μm. Thus, a multilayer functional layer composed of the first layer and the second layer was formed. A 90 degree peel test was performed. The strength of the coating film was 6 N / 12 mm or more. The obtained multilayer functional film can be used as a solar cell.

[Example 7: WO ₃ / Ta ₂ O ₅ multilayer functional layer] (Coating and drying of first layer) The same WO ₃ coating solution as used in the formation of the second layer in Example 2 was used to a thickness of 70 μm. Using a bar coater, apply on a thick aluminum foil (O
Warm air drying sending of ° C., to form a WO ₃ containing coating.

(Application and Drying of Second Layer) Third Layer of Example 3
The same Ta used in the formation of_TwoO_FiveApply the coating solution to the WO
_ThreeApply on the coating film using a bar coater,
Dry by sending warm air of _TwoO_FiveForming a coating film containing
Was.

(Compression of First and Second Layers) The obtained film was subjected to a pressure of 367 N / mm ² per unit area (a pressure of 330 N / mm per unit length in the film width direction).
The length of the compressed portion in the longitudinal direction of the film examined in the same preliminary experiment as in Example 1 was 0.9 mm. ) Was performed using a roll press in the same manner as in Example 1 except for changing to (1). The thickness of the WO ₃ compressed layer after compression was 0.6 μm, and the thickness of the Ta ₂ O ₅ compressed layer was 0.6 μm. Thus, the first layer and the second layer
A multilayer functional layer composed of layers was formed. A 90 degree peel test was performed. The strength of the coating film was 6 N / 12 mm or more.
The obtained multilayer functional film was formed by electrochromic (E
C) It can be used as an element.

[Comparative Example 1: ITO / TiO ₂ Layer] (Formation of First Layer) The same procedure as in Example 1 was performed. (Formation of Second Layer) In the formation of the second layer in Example 1, no compression was performed. A 90 degree peel test was performed. An accurate value could not be measured due to the low strength of the coating film.
/ 12 mm or less.

[Comparative Example 2: ITO / TiO ₂ layer] In the same manner as in Example 5, coating and drying of the first layer, coating and drying of the second layer
Drying was performed. No compression of the first and second layers was performed. A 90 degree peel test was performed. An accurate value could not be measured due to the low strength of the coating film, but it was 0.1 N / 12 mm or less.

Comparative Example 3: ITO / TiO ₂ layer In the same manner as in Example 6, the first layer and the second layer were coated and dried. No compression of the first and second layers was performed. A 90 degree peel test was performed. An accurate value could not be measured due to the low strength of the coating film, but it was 0.1 N / 12 mm or less.

[0099]

[Table 1]

Table 1 shows the results of Examples 1 to 7 and Comparative Examples 1 to 3. All of the functional films of Examples 1 to 7 were excellent in adhesion between the multilayer functional layer and the support film, and each had a desired function. On the other hand, those of Comparative Examples 1 to 3 were inferior in adhesion.

In the above embodiments, examples in which several types of multi-layer functional films were produced were shown. In the same manner as in the above embodiment, a multilayer functional film exhibiting various functions can be manufactured. Therefore, the above-described embodiment is merely an example in every aspect, and should not be construed as limiting. Furthermore, all modifications belonging to the equivalent scope of the claims are within the scope of the present invention.

[0102]

According to the present invention, a multilayer functional film can be obtained by a simple operation at a low temperature by a coating method. ADVANTAGE OF THE INVENTION The multilayer functional film by this invention has sufficient mechanical strength and the bad effect by the binder resin in the conventional coating method is eliminated, As a result, the objective function improves more.

[Brief description of the drawings]

FIG. 1 is a diagram showing an example of a multilayer structure of a functional film of the present invention.

FIG. 2 is a diagram showing an example of a multilayer structure of a functional film of the present invention.

FIG. 3 is a diagram showing an example of a multilayer structure of a functional film of the present invention.

FIG. 4 is a diagram illustrating a 90-degree peel test in an example.

[Explanation of symbols]

 (11): Transparent insulator substrate (12): Transparent conductive layer (13): Transparent insulator layer (14): Chalcopallite structure semiconductor layer (15): Metal electrode (21): Substrate (22): Transparent conductive Layer (23): EL light emitting layer (24): Back electrode (31): Transparent conductive layer (32): First color forming layer (33): Dielectric layer (34): Second color forming layer (35): Transparent conductive Layer (1): Test sample with multilayer functional layer formed (1b): Support (1a): Multilayer functional layer (2): Double-sided tape (3): Stainless steel plate (4): Cellophane tape for fixing ( 5): Cellophane tape (5a): Non-cellophane tape stuck surface (6): Tensiometer

Continued on the front page F-term (reference) 4D075 AE13 AE14 BB05Y BB05Z BB24Y BB93Y BB93Z CA22 CA23 CA24 CA25 CB02 CB06 CB08 DA04 DA06 DB01 DB18 DB20 DB36 DB43 DB48 DC21 DC24 EA10 EB07 EB12 EB13 EB14 EB14 EB14 EB14 EB14 EB14 EB14 EB14 EB14 EB14 AT00A BA03 BA06 BA07 BA25 DE01B DE01C EH462 EJ17B EJ17C GB41 JB07 JG01B JG01C JG04 JG05 JG06 JL08 JN01B JN01C JN02 JN06 JN30 YY00B YY00C 5G307 FA02 FB01 FC03 FC01 5G323 BA02 BB

Claims (13)

[Claims] 1. A functional film having at least two functional layers on a support, wherein at least one of the at least two functional layers is a compressed layer of functional fine particles. Functional membrane. 2. The functional film according to claim 1, wherein, of the at least two functional layers, two layers in contact with each other have different compositions. 3. The functional film according to claim 1, comprising at least two compressed layers of the functional fine particles. 4. A compressed layer of conductive fine particles, wherein at least one of the compressed layers of functional fine particles is a compressed layer of conductive fine particles.
Functional membrane according to 4. 5. The functional film according to claim 4, wherein the compressed layer of the conductive fine particles is a transparent conductive layer. 6. The compressed layer of the functional fine particles is obtained by applying a liquid in which the functional fine particles are dispersed on a support or a functional layer and compressing the functional fine particle-containing layer formed by drying. The functional film according to any one of claims 1 to 5, which is a functional film. 7. The compressed layer of the functional fine particles has a pressure of 44 N /
It is obtained by compressing in mm ² or more compression strength, functional membrane according to any one of claims 1 to 6. 8. A method for producing a functional film having at least two functional layers on a support, wherein at least one of the at least two functional layers is a compressed layer of functional fine particles. A liquid in which the functional fine particles are dispersed is coated on a support or a functional layer, and dried to form a functional fine particle-containing layer. Thereafter, the functional fine particle-containing layer is compressed to obtain a functional fine particle-containing layer. A method for producing a functional film, comprising forming a compression layer. 9. A method for producing a functional film having at least two compressed layers of functional fine particles in contact with each other on a support, comprising applying a liquid in which the functional fine particles are dispersed on the support and drying the liquid. ,
Forming a first functional fine particle-containing layer, and then compressing the first functional fine particle-containing layer to form a first compressed layer of functional fine particles; and then functional fine particles different from the functional fine particles The liquid in which is dispersed is applied on the formed first compressed layer and dried to form a second functional fine particle-containing layer. Thereafter, the second functional fine particle-containing layer is compressed to obtain a functional fine particle. A method for producing a functional film, comprising forming a second compression layer. 10. A method for producing a functional film having at least two compressed layers of functional fine particles in contact with each other on a support, comprising applying a liquid in which the functional fine particles are dispersed on the support and drying the liquid. ,
Forming a first functional fine particle-containing layer, applying a liquid in which functional fine particles different from the functional fine particles are dispersed on the formed first functional fine particle-containing layer, drying the liquid, Forming a functional fine particle-containing layer, and then compressing the first and second functional fine particle-containing layers to form a first compressed layer of functional fine particles and a second compressed layer of functional fine particles;
A method for producing a functional film, comprising forming a compression layer. 11. A method for producing a functional film having at least two compressed layers of functional fine particles in contact with each other on a support, comprising applying a liquid in which the functional fine particles are dispersed on the support, While the layer is in a wet state, a liquid in which functional fine particles different from the functional fine particles are dispersed, is coated on the coating layer,
Drying to form first and second functional fine particle-containing layers, and then compressing the first and second functional fine particle-containing layers to form a first compressed layer of functional fine particles and a second functional fine particle-containing layer 2
A method for producing a functional film, comprising forming a compression layer. 12. The method for producing a functional film according to claim 8, wherein compression is performed with a compression force of 44 N / mm ² or more. 13. The method for producing a functional film according to claim 8, wherein the compression is performed at a normal temperature.