JPH10142402A - Antireflection film and display device arranged therewith - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an antireflection film which exhibits uniformly low reflectivi ty in a wide wavelength region and simultaneously has excellent film strength, durability, resistance to adhesion of contamination and heat resistance by having a layer contg. specific polymer particulates. SOLUTION: The extreme surface of a transparent base material 3 to be subjected to reflection prevention is provided with a microvoid layer 1. This layer 1 is a particulate layer having a low refractive index and contains the polymer particulates having an average grain size of <=200nm. At least one kind of the particulates are fluorine-contained polymers having a hollow shape or gap structure. The layer 1 is a layer (microvoidcontg. layer) in which the air rendered by the voids in the particles coexist with the particle forming polymers and binder components forming films. The monomer unit of the fluorine containing polymers forming the void particulates is, for example, fluoroolefins, etc.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an anti-reflection film which is excellent in mass productivity and anti-contamination properties, and at the same time, realizes high film strength, and a display device having the anti-reflection film.

[0002]

2. Description of the Related Art In recent years, with the spread of liquid crystal display devices, enlargement and outdoor use, toughness under use conditions, for example, improvement in resistance to reflected light (ensure visibility), antifouling property and heat resistance. Is required. Improving the visibility of a display device is an issue related to the main function of the device, and naturally has high importance, and measures for improving the visibility are being actively studied. Generally, visibility is reduced by the reflection of scenery due to surface reflection of external light, and as a countermeasure against this, a method of providing an antireflection film on the outermost surface is generally performed. However,
Since this antireflection film is provided on the outermost surface in order to exhibit its function, many issues of high quality are inevitably concentrated on the performance of the antireflection film from the viewpoint of toughness. For example, reduction of reflectance to the limit (reflectance of 1% or less), prevention of adhesion of fingerprints and fats and oils, easy removal, and maintenance of various performances in a high temperature environment such as under the sun or in a car interior.

Conventionally, as an antireflection film having a wide wavelength range and a low reflectance having a performance capable of covering the entire wavelength range of visible light, a multilayer film formed by laminating a transparent thin film such as a metal oxide has been used. While a single-layer film is effective for monochromatic light, it cannot be effectively prevented from reflecting light having a certain wavelength range.
This is because the larger the number of layers, the more effective the antireflection film in a wide wavelength range. However, such an anti-reflection film formed by laminating three or more layers of metal oxides or the like by means of physical vapor deposition or the like is formed in accordance with the relationship between the refractive index and the film thickness of each layer which is optimally designed in advance. It was necessary to perform physical vapor deposition with the thickness controlled with high precision many times, it was very expensive, and it was not suitable for mass production, which was very difficult to obtain a large area film. . In addition, these multilayer deposition type antireflection films have poor anti-staining properties such as scratch resistance or fingerprint adhesion on the surface, and for this improvement, for example, a new layer made of a fluorine-containing resin is applied. Processing that could sacrifice antireflection was essential.

On the other hand, in addition to the above-described method using a multilayer film, a method for obtaining an effective anti-reflection effect by a film whose refractive index gradually changes at the interface with air is conventionally known. For example, JP-A-2-245702 discloses that
The SiO ₂ ultrafine particles and MgF ₂ ultrafine particles having an intermediate refractive index of the glass substrate and the MgF ₂ were mixed and applied to a glass substrate, gradually SiO toward the coating film surface from the glass substrate surface
_{It is described that when} the mixing ratio of MgF ₂ is increased by decreasing the mixing ratio of ₂ , the change in the refractive index at the interface between the coating surface and the glass substrate becomes gentle, and an antireflection effect is obtained. Further, JP-A-5-13021 discloses an antireflection film using ultrafine particles having a low refractive index, such as MgF ₂ or SiO _2, which has the smallest reflection when the ultrafine particles are regularly arranged on a substrate. It is stated that a rate is obtained.

In each of the above-mentioned methods, it is possible to provide a surface layer having a low reflectance.
Since the antireflection film described in JP-A No. 02-302, can be obtained by stacking coating films having different mixing ratios, there is a problem that the film is complicated and difficult to control the refractive index. In the anti-reflection coating of JP-A No. 1993, it is difficult to change the refractive index slowly because the ultrafine particles of the outermost layer are covered with a binder, and the substrate used is limited because the baking temperature is high. And a sufficient anti-reflection effect cannot be obtained.

[0006]

SUMMARY OF THE INVENTION It is an object of the present invention to exhibit a uniformly low reflectance (reflectance of 1% or less) over a wide wavelength range, and at the same time, to obtain film strength, durability, adhesion to dirt, and heat resistance. An object of the present invention is to provide an antireflection film excellent in low cost at low cost and in a method suitable for large-scale and large-area production.

[0007]

The above-mentioned problems are solved by the following antireflection film. (1) A low-refractive-index layer comprising a layer containing polymer fine particles having an average particle diameter of 200 nm or less, and being a fluoropolymer having at least one kind of hollow or void structure of the fine particles. Anti-reflection film. (2) The antireflection film according to the above (1), wherein at least one of the fine particles is made of a polymer containing a crosslinkable group. (3) The antireflection film according to the above (1) or (2), wherein at least one of the fine particles has a core-shell structure. (4) The antireflection film according to the above (1), wherein the formed low refractive layer contains at least 0.3% by weight or more of fluorine atoms. (5) The antireflection film according to (1), wherein the low refractive index layer is formed on a layer having a higher refractive index. (6) The antireflection film according to the above (1), wherein the surface is subjected to an anti-glare treatment. (7) A display device in which the antireflection film of (1) is arranged.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION The excellent antireflection film obtained by the antireflection film of the present invention will be described below. In the following description, the “fine particles having a hollow shape or void structure” of the present invention are referred to as “void fine particles”, the “voids in the void fine particles” are referred to as “voids in particles”, and the antireflection obtained by forming the void particles into a film. The voids in the film are called "microvoids".

In general, in order to select an anti-reflection function, a method of providing an ultra-thin layer having a refractive index as low as possible on the outermost surface of a substrate is known. The present invention is characterized in that void fine particles are used for the outermost layer (low refractive index layer). FIG. 1 shows an antireflection film made of void fine particles. In the figure, reference numeral 1 denotes a layer (microvoid-containing layer) in which air generated by intraparticle voids is mixed with a particle-forming polymer and a binder component forming a film, and 3 denotes a substrate. The microvoids are uniformly dispersed in one layer. The microvoid layer is provided on the outermost surface of the transparent substrate on which antireflection is to be performed.

The fine particle layer having such a low refractive index is
Not only the single-layer film shown in FIG. 1 but also the uppermost layer of the multilayer film can be used. FIG. 2 shows a reflection in which a layer 2 having a higher refractive index than the refractive index of the substrate is provided on the substrate film, and a layer containing the fluoropolymer fine particles having voids in the particles of the present invention is further provided thereon. 3 shows a protective film. Obtaining an effective antireflection film in a wider wavelength range by forming a multilayer in this way is based on the same principle as that of the prior art. For example, as disclosed in JP-A-59-50401, in a two-layer film, the refractive index n ₁ and the film thickness d ₁ of the first layer in contact with the substrate and the second layer in contact with the first layer By setting the refractive index n _{2 of the} layer and the thickness d ₂ to satisfy the following relationship, the function as an antireflection film is optimized.
The antireflection conditions for such a multilayer film have been known for a long time. First layer mλ / 4 × 0.7 <n ₁ d ₁ <mλ / 4 × 1.
3 Second layer nλ / 4 × 0.7 <n ₂ d ₂ <nλ / 4 × 1.
3 where m is a positive integer and n is an odd positive integer.

The present invention is characterized in that the microvoids carried by the void microparticles and held in the film are uniform, and that the microvoids have a size that does not scatter light. In other words, the low refractive index layer is microscopically a microvoid-containing porous film, but can be regarded as an optically or macroscopically uniform film.
For this reason, the macroscopic refractive index of the microvoided film becomes lower by an amount corresponding to the volume fraction of air introduced by converting the polymer into microvoided fine particles. That is, the refractive index of this film is represented by the volume average of the refractive index of the binder component forming the film (having a value larger than 1) and the refractive index of the introduced air (which is 1.00). , Resulting in a value lower than the refractive index of the binder component used.

The particle size of the fine particles used in the present invention is 200
nm or less. If the particle diameter increases, forward scattering increases, and if it exceeds 200 nm, the scattered light is undesirably colored. Further, the thickness is preferably 70 nm or less from the viewpoint of optical performance and film quality, and particularly preferably 50 nm or less. Such fine particles can be manufactured and obtained as a polymer latex.

The monomer unit of the fluoropolymer forming the void fine particles of the present invention is not particularly limited as long as the monomer contains a fluorine atom. Specific examples of these monomers include, for example, fluoroolefins (for example, fluoroethylene, vinylidene fluoride, tetrafluoroethylene, hexafluoropropylene, perfluoro-2,2-dimethyl-1,3-dioxole, etc.), and the following general formula: Acrylic, partially or fully fluorinated alkyl ester derivatives of methacrylic acid, fully or partially fluorinated vinyl ethers, and the like, and the desired polymer is obtained by copolymerizing any of these monomers in any ratio. be able to.

[0014]

Embedded image

In the polymer forming the void fine particles of the present invention, a monomer containing no fluorine atom may be used in addition to the above-mentioned fluorine-containing monomer. There is no particular limitation on the monomer units that can be used in combination, and for example, olefins (ethylene, propylene, isoprene, vinyl chloride, vinylidene chloride, etc.), acrylates (methyl acrylate, ethyl acrylate, 2-ethylhexyl acrylate, etc.) ), Methacrylates (eg, methyl methacrylate, ethyl methacrylate, butyl methacrylate, ethylene glycol dimethacrylate), styrene derivatives (styrene, divinylbenzene, vinyltoluene, α-
Methyl styrene), vinylyl ethers (methyl vinyl ether, etc.), vinyl esters (vinyl acetate, vinyl propionate, vinyl cinnamate, etc.), acrylamides (N-tert-butyl acrylamide, N-cyclohexyl acrylamide, etc.), methacrylamides,
Acrylonitrile derivatives and the like can be mentioned.

When the above-mentioned fluorine-containing monomer is used, the refractive index of the polymer obtained decreases as the content of fluorine atoms in all the monomers used increases. In order to sufficiently lower the refractive index of the antireflection film for the purpose of the present invention, the polymer preferably contains 35% by weight to 80% by weight of fluorine atoms, particularly preferably 45% by weight to 7% by weight.
5% by weight.

The amount of the voids in the particles or hollow particles having a hollow structure used in the present invention is not particularly limited. However, from the viewpoint of maintaining the shape of the particles and introducing effective voids into the film, 3% by volume is preferred. As described above, the content is 50% by volume or less, and particularly preferably 5% by volume or more and 35% by volume or less. These particles can be easily synthesized by ordinary emulsion polymerization. The hollow particles are described in JP-A-1-1853111.
JP-A-6-248012, JP-A-8-20604
And methods equivalent thereto.
Further, the particles having voids in the particles generally contain a monomer having two or more polymerizable unsaturated groups in the molecule in an amount of 15 to 5 as in the production process of the porous ion exchange resin.
It can be easily synthesized by emulsion polymerization using about 0% by weight.

As described above, the refractive index of the layer decreases as the content of microvoids increases. For this reason, in order for the antireflection film of the present invention to have a sufficiently low refractive index, the amount of microvoids contained in the layer made of the fluoropolymer fine particles is preferably 3% by volume to 50% by volume, and particularly preferably 5% by volume. % By volume to 35% by volume.

The polymer particles of the antireflection film in the present invention can be either crystalline or amorphous.
In addition, the glass transition point (T
g) is not particularly limited, and from the viewpoint of maintaining voids during film formation,
It is preferable that Tg is equal to or higher than the film forming temperature. However, if the Tg is higher than the film forming temperature, the fusion of the particles is hindered, a continuous film is not formed, and there is a concern that the film strength is deteriorated. It is desirable to use a material whose effect is adjusted to an optimum region by Tg.

The microvoided fine particles used in the present invention may be used by mixing arbitrary two or more kinds of particles in an arbitrary ratio in one antireflection film. Further, the microvoided fine particles of the present invention may be used in combination with fine particles having no void or hollow structure outside the present invention. In this case, the polymer fine particles outside the present invention to be used in combination are not particularly limited, but may be particles obtained by ordinary emulsion polymerization, or may be an emulsion of a water-insoluble polymer obtained by separately prepared organic solvent-based solution polymerization, It may be a water-soluble polymer (hereinafter referred to as a binder). The mixing ratio of the binder used in combination with the microvoided fine particles of the present invention is not particularly limited, but from the viewpoint of enhancing the film quality and introducing effective voids into the film, the mixing ratio of the fine particles of the present invention is 3%.
0% to 90% by weight is preferred, and 50% to 80% by weight is particularly preferred.

The Tg of the binder used in combination is preferably lower than the Tg of the polymer component forming the fine particles of the present invention. Thereby, the binder used together is deformed at the time of film formation and serves as a binder between the fine particles of the present invention,
Sufficient film strength can be expected. However, the Tg of the binder used in combination is the Tg of the polymer component forming the fine particles of the present invention.
When the particle size is very close to g, the fine particles of the present invention are deformed and microvoids are reduced. Therefore, the Tg of the binder used in combination is preferably 5 # C or more lower than the particles of the present invention,
Considering the width of Tg and the fluctuation of the film forming temperature, it is particularly preferable that the temperature is lower by 20 # C or more.

The co-bonding between the particles can also be achieved by introducing the crosslinkable functional group by the above-mentioned combined binder mutually reacting with radiation energy such as light or electron beam or heat energy such as heating or electromagnetic wave. The film strength can be improved by the generation. The thing which can be suitably used as a crosslinkable group is not particularly limited as long as it is a functional group which reacts by radiation or heat, and examples thereof include an isocyanate group, a block isocyanate group, an epoxy group, an aziridine group, an oxazoline group, and an aldehyde group. , Carbonyl group, hydrazine group, carboxyl group, methylol group, in addition to compounds having an active methylene group, vinyl sulfonic acid, acid anhydride, cyanoacrylate derivative, melamine, etherified methylol, ester, functional group selected from urethane and the like Including particles. Further, in the present invention, the cross-linking group is not limited to the above-mentioned compound, but may be one which shows reactivity as a result of decomposition of the above-mentioned functional group. The crosslinkable compound to be used may be a combination of two or more compounds having a group capable of reacting with each other, or a compound having a plurality of self-crosslinkable groups such as a vinyl group and an active methylene group in a molecule. May be.

As the substrate on which the antireflection film of the present invention is formed, various plastic films can be used, and cellulose derivatives (for example, triacetyl- (TAC), diacetyl-, propionyl-, butanoyl-, acetylpropionyl-acetate) can be used. , Nitro-, etc.), polyamides,
Polycarbonate, polyester described in JP-B-48-40414 (especially polyethylene terephthalate, poly-1,4-cyclohexane dimethylene terephthalate,
Polyethylene 1,2-diphenoxyethane-4,4-dicarboxylate, polybutylene terephthalate, polyethylene naphthalate, etc.), polystyrene, polypropylene, polyethylene, polymethylpentene, polysulfone, polyethersulfone, polyarylate, polyetherimide Various transparent resins such as polymethyl methacrylate and the like are preferably used.

When used as a multilayer film, the following materials can be used as the material of the high refractive index layer provided below the low refractive index layer.

As the organic material, a film-forming substance having a relatively high refractive index, for example, polystyrene, a polystyrene copolymer, polycarbonate, an aromatic ring other than polystyrene,
Various polymer compositions having a heterocyclic ring, an alicyclic cyclic group, or a halogen group other than fluorine, various thermosetting resin-forming compositions using a melamine resin, a phenol resin, or an epoxy resin as a curing agent, an alicyclic ring A urethane-forming composition comprising a formula or an aromatic isocyanate and / or a polyol thereof and a polyol, and a composition containing various modified resins or prepolymers capable of radical curing by introducing a double bond into the above compound are preferable. Used. In addition, as the organic material in which the inorganic fine particles are dispersed, a material having a lower refractive index than that in the case where the organic material is used alone is generally used because the inorganic fine particles have a high refractive index.
In addition to the organic materials described above, vinyl copolymers including acrylics, polyester (including alkyd) polymers,
Various organic materials that can stably disperse inorganic fine particles such as cellulose polymer, urethane polymer, and various curing agents that cure them, and compositions having curable functional groups can be used. is there. Further, an organic-substituted silicon-based compound can be included therein.

[0026] These silicon-based compounds have the general formula ^{_{R 1 a R 2 b SiX 4-}} (a + b) ( wherein R ^1, R ² are each an alkyl group, an alkenyl group,
Allyl group, or halogen group, epoxy group, amino group,
Hydrocarbon groups having a mercapto group, a methacryloxy group or a cyano group. X is a hydrolyzable substituent selected from alkoxyl, alkoxyalkoxyl, halogen and acyloxy groups. a and b are each an integer of 0 to 2, and a + b is 1 or 2. ) Or a hydrolysis product thereof.

As the inorganic compound dispersed therein, oxides of metal elements such as aluminum, titanium, zirconium and antimony are preferably used. These may be provided in finely divided form as a powder or as a colloidal dispersion in water and / or other solvents. These are mixed and dispersed in the above organic material or organosilicon compound.

Examples of the inorganic material which is capable of forming a film and can be dispersed in a solvent or itself is a liquid include alkoxides of various elements, salts of organic acids, and coordination compounds bonded to coordination compounds. Examples include titanium tetraethoxide, titanium tetra-i-propoxide, titanium tetra-n-propoxide, titanium tetra-n-butoxide,
Titanium tetra-sec-butoxide, titanium tetra-tert
-Butoxide, aluminum triethoxide, aluminum tri-i-propoxide, aluminum tributoxide, antimony triethoxide, antimony tributoxide, zirconium tetraethoxide, zirconium tetra-i-propoxide, zirconium tetra-n-
Propoxide, zirconium tetra-n-butoxide,
Zirconium tetra-sec-butoxide, metal alcoholate compounds such as zirconium tetra-tert-butoxide, further di-isopropoxytitanium bisacetylacetonate, di-butoxytitanium bisacetylacetonate, di-ethoxytitanium bisacetylacetonate, Bisacetylacetone zirconium, aluminum acetylacetonate, aluminum di-n-
Chelating compounds such as butoxide monoethyl acetoacetate, aluminum di-i-propoxide monomethyl acetoacetate, and tri-n-butoxide zirconium monoethyl acetoacetate, and also zirconium ammonium carbonate or an active inorganic polymer containing zirconium as a main component Can be given. In addition to those described above, various alkyl silicates or hydrolysates thereof, and finely divided silica, particularly silica gel dispersed in a colloidal form, are used as those which have a relatively low refractive index but can be used in combination with the above compounds.

Each layer forming the anti-reflection layer of the present invention may be formed by a generally known method such as dip coating, air knife coating, curtain coating, roller coating, wire bar coating, gravure coating, or US It can be applied by an extrusion coating method using a hopper described in Japanese Patent No. 2,681,294. Also, if necessary, U.S. Pat.
No. 761,791, 3,508,947, 2,94
No. 1,898 and 3,526,528, and two or more layers can be coated simultaneously by the method described in Yuji Harazaki, “Coating Engineering”, page 253 (published by Asakura Shoten in 1973). .

The low-refractive-index antireflection layer of the present invention may be provided with a hard coat layer, a moisture-proof, antistatic layer and the like as an intermediate layer. As the hard coat layer, silica-based compounds can be used in addition to acrylic-based, urethane-based, and epoxy-based polymers.

The surface of the low-refractive-index antireflection film layer of the present invention can be formed with an organic or inorganic compound to provide an anti-glare effect of scattering external light and preventing the appearance of scenery or the like. The anti-reflection film may be used alone or in combination with an anti-glare effect in a liquid crystal display (LCD),
Plasma display (PDP), electroluminescence display (ELD), cathode ray tube display (CR
By applying the present invention to an image display device such as T) and preventing reflection of external light, visibility can be significantly improved.

[0032]

The present invention will be described below in detail with reference to examples, but the present invention is not limited to these examples.

(Synthesis of polymer fine particles having voids) 1) Synthesis of BP1 30 g of sodium dodecyl sulfate was placed in a two-liter three-necked flask equipped with a cooling tube and a stirrer, and distilled water was added to 1350 m3.
and then add 210 g (0.89 mol) of hexafluoroisopropyl methacrylate.
And a mixed solution of 90 g (0.69 mol) of divinylbenzene was added, and the mixture was stirred at a speed of 200 rpm under a nitrogen stream.
The reaction vessel was heated to 75 ° C., and 50 ml of an 8% aqueous solution of sodium persulfate was added to carry out polymerization for 2 hours. In addition, 8
A 50% aqueous solution of sodium persulfate was added, followed by polymerization for 2 hours. The reaction solution was cooled to room temperature, dialyzed using a cellulose membrane having a molecular weight cut off of 10,000 to remove excess surfactants and inorganic salts, and then filtered to remove insolubles to remove a fine milky white color. 2,780 g of an aqueous solution was obtained. This solution has a nonvolatile content of 1
It was a fine latex liquid containing 0.3% by weight and having an average particle diameter of 48 nm. The particles contained in this latex were porous spherical particles having voids of about 19% by volume. The particle size was evaluated by a dynamic light scattering method using a Coulter particle measuring device N4. The particle shape was observed using a scanning electron microscope, the porosity measured the refractive index of the particles, and the volume fraction of air was back calculated from the difference from the calculated value of the refractive index of the polymer obtained from the monomer composition used. .

2) Synthesis of BP2 30 g of sodium dodecyl sulfate was placed in a 2 liter three-necked flask equipped with a cooling pipe and a stirrer, and 1350 m of distilled water.
165 g (0.70 mol) of hexafluoroisopropyl methacrylate and 45 g of glycidyl methacrylate (0.3 g).
2 mol) and 90 g (0.69 mol) of divinylbenzene were added, and the mixture was stirred at a speed of 200 rpm under a nitrogen stream. The reaction vessel was heated to 75 ° C., and 50 ml of an 8% aqueous solution of sodium persulfate was added to carry out polymerization for 2 hours.
During this time, a 3% aqueous sodium hydroxide solution was appropriately added so as to keep the pH of the reaction solution in the range of 6.3 to 7.7. Further, 50 ml of an 8% aqueous sodium persulfate solution was added, and polymerization was performed for 2 hours. Similarly, the pH of the reaction solution was adjusted to 6.4 to 6.4.
It continued to adjust to 7.9. Cool the reaction to room temperature,
After dialysis using a cellulose membrane having a molecular weight cut off of 10,000 to remove excess surfactants and inorganic salts, insoluble components were removed by filtration to obtain 3019 g of a fine milky white aqueous solution. This solution was a fine latex liquid containing 9.3% by weight of nonvolatile components and having an average particle diameter of 54 nm. The particles contained in this latex were porous spherical particles having voids of about 14% by volume. The particle size was evaluated by a dynamic light scattering method using a Coulter particle measuring device N4. The particle shape was observed using a scanning electron microscope, the porosity measured the refractive index of the particles, and the volume fraction of air was back calculated from the difference from the calculated value of the refractive index of the polymer obtained from the monomer composition used. .

The other void particles used in the present invention could be easily synthesized by the same method as the above-mentioned emulsion polymerization method or a method similar thereto. Table 1 below shows the void fine particles (BP1 to BP7) of the present invention synthesized by these methods.

[0036]

[Table 1]

Example 1 (coating of antireflection layer and evaluation of performance)

An aqueous solution (E1 to E10) prepared with the composition shown in Table 2 was applied to a triacetylcellulose (hereinafter referred to as TAC) film using a void fine particle shown in Table 1 above using a spin coater. After drying at #C for 120 minutes, a low refractive index layer having a thickness of 100 nm was formed. For the obtained films (X1 to X10), measurement of refractive index and luminous reflectance and measurement of film strength with a sapphire needle were performed. The results are shown in Table 3.

[0039]

[Table 2]

[0040]

[Table 3]

The same procedure as in Example 1 was repeated except that the fine particles of the present invention used in Example 1 were replaced with particles (NP1 to NP3) outside the present invention as shown in Table 2, and the comparative sample solution coating solution (F1 to F3) was used. F4) was prepared and formed into a film under the same conditions to obtain comparative samples (Y1 to Y4). The obtained film was subjected to the same method as in Example 1 to obtain a film having a refractive index and a luminous reflectance (a light wavelength of 400).
(mean reflectance value from nm to 800 nm) and film strength measurement with a sapphire needle. The results are shown in Table 3.

Example 2 (Preparation of multilayer antireflection film) (1) Coating of first layer (hard coat layer) A TAC film having a thickness of 90 µm was coated with 5% by weight of dipentaerythritol hexaacrylate and light. Polymerization initiator (trade name: Irgacure 907, manufactured by Ciba Geigy)
0.5% by weight, photosensitizer (trade name: Kaya Cure DET)
X, manufactured by Nippon Kayaku Co.) A toluene solution containing 0.2% by weight was applied to a thickness of 8 μm using a wire bar, dried, heated to 100 ° C., and a high-pressure mercury lamp of 12 W / cm was used. For 1 minute to crosslink. Then, it was allowed to cool to room temperature.

(2) Coating of Second Layer (High Refractive Index Layer) Separately synthesized poly (n-butyl methacrylate-co-methacrylic acid) latex (copolymer composition weight ratio: 80: 2)
0, average particle diameter 63 nm, solid content concentration 12.5% by weight:
HP1) 100 g and tin oxide fine particles (obtained from Ishihara Sangyo Co., Ltd.) 25 g were mixed, further, dipentaerythritol hexaacrylate 6 g, and a photopolymerization initiator (trade name: Irgacure 907, manufactured by Ciba Geigy) 0 .5
g, 0.2 g of a photosensitizer (trade name: Kayacure DETX, manufactured by Nippon Kayaku Co., Ltd.) An emulsion liquid obtained by emulsifying and dispersing 20 g of ethyl acetate in 100 g of water using 1 g of sodium dodecylbenzenesulfonate was mixed and stirred. A coating solution was prepared.
This liquid was applied to a thickness of 0.16 μm on the first layer prepared above using a wire bar, and after drying,
C. and cross-linked by irradiating with ultraviolet rays for 1 minute using a 12 W / cm high-pressure mercury lamp, and then allowed to cool to room temperature.

(3) Preparation of Third Layer (Low Refractive Index Layer) 6 g of dipentaerythritol hexaacrylate, 0.5 g of a photopolymerization initiator (trade name: Irgacure 907, manufactured by Ciba Geigy), a photosensitizer ( Product Name: Kaya Cure DE
TX, manufactured by Nippon Kayaku Co., Ltd.) 0.2 g of ethyl acetate 20 g of sodium dodecylbenzenesulfonate in 10 g of water
A coating solution was prepared by mixing and stirring 100 g of the previously synthesized latex BP1 and the emulsion liquid emulsified and dispersed in 0 g. This liquid was applied to a thickness of 0.10 μm using a wire bar on the second layer prepared above, and after drying,
The mixture was heated to 100 ° C. and irradiated with ultraviolet rays for 1 minute using a high-pressure mercury lamp of 12 W / cm for crosslinking. Then, it was allowed to cool to room temperature. The thus-obtained film coated with the first to third layers exhibited a surface reflectivity of 0.4% and a surface hardness of 5H (by a pencil hardness method). : ARF1).

The antireflection film A was prepared in the same manner as in the above example except that HP1 and BP1 were made of the materials shown in Table 4 below, and the amount of liquid preparation was changed so that the solid content of the coating solution was the same.
RF2 to 6 were obtained. Table 4 shows the surface performance of these films.
Are shown together. At the same time, the compound used for the third layer was changed to particles NP1 to NP3 outside the present invention, and the amount of the liquid preparation was changed so that the solid content concentration of the coating solution was the same. 3 was obtained. These surface performances are also shown in Table 4.

[0046]

[Table 4]

As is clear from this example, the antireflection film of the present invention not only has a very low reflectance and an excellent antireflection performance having a wide wavelength range, but also has a sufficiently tough film strength. You can see that it is.

[0048]

According to the present invention, by coating a film using fluoropolymer fine particles having a hollow structure or a void structure, the adhesion between particles can be achieved without impairing the voids in the process of forming a film having voids. Can be improved. As a result, very good optical properties are exhibited as an anti-reflection film, and a low-cost, large-area anti-reflection film having excellent film properties such as film strength and scratch resistance can be provided in a form having suitability for production. .

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of an antireflection film made of a layer comprising a fluoropolymer fine particle of the present invention.

FIG. 2 shows a layer comprising the fluoropolymer fine particles of the present invention,
FIG. 2 shows a cross-sectional view of an antireflection film made of a layer having a higher refractive index than a substrate.

[Explanation of symbols]

 1 low refractive index layer 2 high refractive index layer 3 substrate

Claims (7)

[Claims] 1. A low refractive index comprising a layer containing polymer fine particles having an average particle diameter of 200 nm or less, wherein at least one of the fine particles is a fluorine-containing polymer having a hollow or void structure. Antireflection film having a layer. 2. The antireflection film according to claim 1, wherein at least one of the fine particles is made of a polymer containing a crosslinkable group. 3. The anti-reflection coating according to claim 1, wherein at least one of the fine particles has a core-shell structure. 4. The method according to claim 1, wherein the formed low refractive index layer has a thickness of at least 0.3.
2. The antireflection film according to claim 1, wherein the antireflection film contains a fluorine atom in a weight fraction or more. 5. The antireflection film according to claim 1, wherein the low refractive index layer is formed on a layer having a higher refractive index. 6. The anti-reflection coating according to claim 1, wherein the surface is subjected to anti-glare treatment. 7. An anti-reflection coating having a layer containing polymer fine particles having an average particle diameter of 200 nm or less, and having a low refractive index layer in which at least one of the fine particles is a fluoropolymer having a hollow or void structure. A display device comprising a film disposed thereon.