JP2009282324A - Optical laminate - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an optical laminate suitable for an antireflective film. <P>SOLUTION: The optical laminate has a low refractive index layer and a high refractive index layer, wherein the outermost layer of at least one surface of the laminate is the low refractive index layer. Organic fine particles are dispersed in the low refractive index layer and the high refractive index layer, the thickness of the low refractive index layer is 50-300 nm and the molar ratio (F/C) of the quantity of fluorine to the quantity of carbon present in 40 nm depth in the measurement in the depth direction from the surface of the low refractive index layer to the high refractive index layer side by a C60 ion gun-mounting X-ray photoelectron spectroscopic analysis is ≥0.2. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an optical laminate.

  Various display devices such as a liquid crystal display (LCD), a plasma display (PDP), and an organic electroluminescence display (OELD) have been actively developed in recent years, and high quality and low cost are the subject of development. Yes.

  Improvement of visibility is an important theme for high quality. In order to improve the visibility, in addition to increasing the viewing angle and increasing the definition, improving the antireflection property is one of the important technical approaches. In addition, antireflection shows preventing the fall of the contrast and what is called reflection by the reflected light originating in the external light (incident light) which injected into the display screen.

  In addition, cellular phones, portable terminals, digital cameras, digital video cameras, and the like are currently spreading rapidly, but their usage environment is often outdoors. Visibility is likely to be impaired outdoors due to reflected light compared to indoors. In addition, devices used outdoors are generally likely to be touched by hand or in contact with other objects. For this reason, compared with the apparatus used indoors, the high antireflection property and protection of a display screen are calculated | required.

In order to reduce the reflected light of the display screen, an optical film having an antireflection layer is generally provided on the surface of the display screen.
As an antireflection layer, it has a low refractive index layer and a high refractive index layer, and reduces the reflected light by utilizing the interference of light reflected at each interface due to the difference in refractive index. Some layers have a low refractive index on the surface side of the layer and gradually increase the refractive index in the depth direction in the display screen direction to reduce reflected light.

  By the way, a fluorine-containing polymer containing a fluorine atom generally has a low refractive index, and it is possible to add antifouling properties, and an amorphous fluorine-based polymer is generally excellent in transparency, so an antireflection layer is formed. Often used as a polymer.

As typical polymers for forming the antireflection layer, various fluororesins such as a tetrafluoroacrylate polymer (for example, see Patent Document 1) and a perfluorooctylethyl acrylate polymer (for example, see Patent Document 2). In these polymers, fluorine is present only in the side chain, and a methylene group (—CH ₂ —) is present in the main chain. Even if a fluorine monomer or a fluororesin is coated on the support as the low refractive index layer, the coating is difficult unless it is mixed with another resin having good binder and coating properties and high hardness.

Moreover, the antireflection film with low reflectivity is obtained by directly fluorinating the surface of the sulfur-containing resin substrate layer of the film having a sulfur-containing resin substrate layer containing a sulfur-containing resin such as polyphenylene sulfide using fluorine gas. Is known to be obtained (see, for example, Patent Document 3).
Japanese Patent No. 3361857 JP 2003-261797 A JP 2007-178996 A

  When the sulfur-containing resin described in Patent Document 3 is directly fluorinated using fluorine gas, depending on the fluorine gas treatment conditions, a carbon- It has been found that the heteroatom bond may be broken, and as a result, the obtained fluororesin has a low molecular weight and is attached to the surface in an oily state (raised), and can be wiped off with a solvent such as ethanol. Further, since the above-described embossing occurs, it is difficult to sufficiently fluorinate the polymer, and as a result, it is difficult to sufficiently reduce the refractive index.

  Further, it is generally known that a low refractive index layer included in the antireflection film is preferably one having a small refractive index difference from the air layer (refractive index 1.0). In addition, the antireflection film is desired to have excellent light transmittance and high hardness from the viewpoint of screen protection.

  The present invention has been made in view of the above-described problems of the prior art, and an object thereof is to provide an optical laminate suitable for an antireflection film.

  As a result of intensive studies to achieve the above problems, the present inventors have found that the above problems can be solved by adjusting the amount of fluorine present near the surface of a laminate having a low refractive index layer and a high refractive index layer. The headline and the present invention were completed.

  That is, the optical laminate of the present invention is a laminate having a low refractive index layer and a high refractive index layer, and the outermost layer on at least one surface is the low refractive index layer, and the low refractive index layer and the high refractive index layer Organic fine particles are dispersed in the refractive index layer, the thickness of the low refractive index layer is 50 to 300 nm, and the C60 ion gun mounted X-ray from the surface of the low refractive index layer to the high refractive index layer side. When the depth direction analysis is performed by photoelectron spectroscopy, the molar ratio (F / C) of fluorine and carbon at a depth of 40 nm is 0.2 or more.

Organic fine particles (α) are dispersed in the low refractive index layer, and the organic fine particles (α) have a chain formed by polymerizing a crosslinked structure and a polymerizable group having a carbon / carbon double bond. At least one ring selected from the group consisting of an aromatic ring and an alicyclic ring, wherein the chain is at least one fluorine selected from the group consisting of a —CF ₂ — group and a —CHF— group It is preferable that a fluorine-based polymer having a substituted methylene group and having a fluorine atom bonded to at least a part of the carbon atoms constituting the ring is contained.

  Organic fine particles (α) are dispersed in the low refractive index layer, and the organic fine particles (α) have a chain formed by polymerizing a crosslinked structure and a polymerizable group having a carbon / carbon double bond. A polymer (raw polymer) having at least one ring selected from the group consisting of an aromatic ring and an alicyclic ring and having the methylene group in the chain is subjected to a direct fluorination treatment using fluorine gas It is preferable that the polymer obtained by this is contained.

  Organic fine particles (β) are dispersed in the high refractive index layer, and the organic fine particles (β) have a chain formed by polymerizing a crosslinked structure and a polymerizable group having a carbon / carbon double bond. And a polymer (raw material polymer) having at least one ring selected from the group consisting of an aromatic ring and an alicyclic ring, wherein the chain has a methylene group.

  The optical layered body of the present invention preferably has the high refractive index layer and the low refractive index layer on a support.

  The low refractive index layer constituting the optical laminate of the present invention has a lower refractive index than the conventional optical laminate and is excellent in light transmittance.

Next, the present invention will be specifically described.
The optical layered body of the present invention is a layered body having a low refractive index layer and a high refractive index layer, wherein the outermost layer on at least one surface is the low refractive index layer, and the low refractive index layer and the high refractive index layer. Organic fine particles are dispersed in the layer, and the thickness of the low refractive index layer is 50 to 300 nm. From the surface of the low refractive index layer to the high refractive index layer side, C60 ion gun mounted X-ray photoelectron spectroscopy When the depth direction analysis is performed by the analysis method, the molar ratio (F / C) of the abundance of fluorine and carbon at a depth of 40 nm is 0.2 or more.

  The optical layered body of the present invention has a low refractive index layer and a high refractive index layer. From the surface of the low refractive index layer to the high refractive index layer side, a C60 ion gun mounted X-ray photoelectron spectroscopy method is used. The molar ratio (F / C) of the abundance of fluorine and carbon at a depth of 40 nm when depth direction analysis is performed can be measured by the following method.

  First, a cross section of the optical laminate (sample) is photographed using a transmission electron microscope (TEM Hitachi, Ltd. H-7000 100 kV), and the thickness of the low refractive index layer is determined from the image. Since fluorine has a high electron density, a layer containing fluorine and a layer not containing fluorine are darker than the layer containing no fluorine, and the transmission electron microscope is brighter and darker. The thickness of the low refractive index layer can be confirmed from the image.

Next, a C60 ion gun mounted X-ray photoelectron spectrometer (C60-XPS, Quan
Using tera SXM (manufactured by PHI), the optical laminate (sample) is analyzed in the depth direction, and the F1s peak area and the C1s peak area are measured. The depth direction analysis can be performed in the depth direction by cutting the sample with C60.

  By dividing the F1s peak area and the C1s peak area by the respective relative sensitivity coefficients (RSFs), a fluorine quantitative value and a carbon quantitative value indicating the abundance of fluorine and carbon are calculated. The ratio between the quantitative value of fluorine and the quantitative value of carbon (the quantitative value of fluorine / the quantitative value of carbon) is the molar ratio (F / C) of the abundance of fluorine and carbon.

In the present invention, the C60 sputtering rate is set to 2 nm / min. However, the sputter speed is the speed when the SiO ₂ is scraped, and the sputter speed varies depending on the configuration of the sample. Therefore, the thickness of the low refractive index layer obtained from the transmission electron microscope image is used, Obtain the sputtering rate.

  That is, when a depth direction analysis is performed on a sample using a C60 ion gun mounted X-ray photoelectron spectrometer, the time during which the molar ratio (F / C) of fluorine to carbon is less than 0.1 is obtained. Is x (min), and if the thickness of the low refractive index layer obtained from the transmission electron microscope image is y (nm), the sputtering rate is calculated as y / x (nm / min). .

Based on the sputtering rate (y / x (nm / min)), the molar ratio (F / C) of the abundance of fluorine and carbon at a depth of 40 nm can be obtained.
In addition, the measurement conditions at the time of performing a depth direction analysis using a C60 ion gun mounting X-ray photoelectron spectrometer are as follows.
X-ray source: Monochromated Al (1486.6 eV)
Detection area: 100 μmφ
Extraction angle: 45deg
Detection depth: 4-5nm
Sputtering conditions: ion species C ₆₀ + acceleration voltage 10 kV
Sputtering speed: about 2 nm / min (SiO ₂ equivalent value)
F1s relative sensitivity coefficient: 110.554
C1s relative sensitivity coefficient: 34.191
(High refractive index layer)
In the high refractive index layer of the optical layered body of the present invention, organic fine particles are dispersed. The optical layered body of the present invention can be obtained by separately producing a high refractive index layer and a low refractive index layer and then laminating them. Usually, the following organic fine particles (β) are dispersed. It can be obtained by forming a high refractive index layer and subjecting the high refractive index layer to direct fluorination treatment using fluorine gas, thereby fluorinating the surface of the high refractive index layer and forming a low refractive index layer.

  The organic fine particles (β) are at least one selected from the group consisting of a crosslinked structure, a chain formed by polymerization of a polymerizable group having a carbon / carbon double bond, and an aromatic ring and an alicyclic ring. And a polymer in which the chain has a methylene group (raw material polymer).

The raw material polymer is usually a polyfunctional monomer polymer or a copolymer of a polyfunctional monomer and a monofunctional monomer.
Above all, the raw material polymer is multifunctional from the viewpoint of adjusting the polymerization rate at the time of manufacturing the raw material polymer, the moldability of the raw material polymer, the flexibility of the molded product and the coated film of the raw material polymer, the weather resistance, etc. A copolymer of a functional monomer and a monofunctional monomer is preferable.

  Examples of polyfunctional monomers include divinylbenzene, diisopropenylbenzene, aromatic divinyl compounds such as 4,4′-divinylbiphenyl, and bisphenols such as 2,2-bis (4- (meth) acryloyloxyethyldiphenyl) propane. A derivatives, diphenylfluorene derivatives such as 9,9-bis (4-methacryloxyethoxy) phenyl) fluorene, ethylene glycol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, 1,10-decanediol Polyfunctional (meth) acrylates such as di (meth) acrylate, trimethylolpropane tri (meth) acrylate, and pentaerythritol tetra (meth) acrylate can be used.

These polyfunctional monomers may be used individually by 1 type, and may use 2 or more types.
In addition, (meth) acrylate shows a methacrylate and an acrylate.
Among these, when the high refractive index layer is subjected to direct fluorination treatment using fluorine gas, the resulting aromatic divinyl compound has a large refractive index change between the low refractive index layer and the high refractive index layer. It is preferable to use divinylbenzene, diisopropenylbenzene, and 4,4′-divinylbiphenyl.

  Examples of the monofunctional monomer include aromatic vinyl compounds such as styrene, o, m, p-ethylstyrene, isopropenylbenzene, and p-phenylstyrene, benzyl (meth) acrylate, phenoxyethyl (meth) acrylate, isobornyl ( (Meth) acrylic ester compounds such as (meth) acrylate and tert-butyl (meth) acrylate can be used.

These monofunctional monomers may be used individually by 1 type, and may use 2 or more types.
Among these, it is preferable to use an aromatic vinyl compound having a large refractive index change before and after the direct fluorination treatment when the high refractive index layer in which the organic fine particles (β) are dispersed is directly fluorinated. More preferably, styrene, o, m, p-ethylstyrene, isopropenylbenzene, or p-phenylstyrene is used.

In addition, in the monomer used when manufacturing a raw material polymer, at least 1 sort (s) needs to have at least 1 sort (s) of a ring selected from the group which consists of an aromatic ring and an alicyclic ring.
The raw polymer is at least one polyfunctional monomer selected from the group consisting of divinylbenzene, diisopropenylbenzene, 4,4′-divinylbiphenyl, styrene, o, m, p-ethylstyrene, In the case of a copolymer with at least one monofunctional monomer selected from the group consisting of propenylbenzene and p-phenylstyrene, the skeleton of the polymer is particularly preferably a carbon skeleton. In the direct fluorination treatment, since the carbon-heteroatom bond is easily cleaved as compared with the carbon-carbon bond, the skeleton of the raw material polymer is preferably a carbon skeleton. The skeleton means a framework obtained by removing hydrogen atoms and substituents from the structural formula of the polymer.

In consideration of dispersibility in solvents and binders, it is also possible to copolymerize a polar acrylic monomer having no aromaticity.
When the raw material polymer has a structural unit derived from the monofunctional monomer and a structural unit derived from the polyfunctional monomer, the molar ratio (structural unit derived from the monofunctional monomer: many The structural unit derived from the functional monomer is preferably 10:90 to 95: 5, more preferably 30:70 to 90:10, from the viewpoint of ease of polymerization.

In addition, the molar ratio of the structural unit derived from a monofunctional monomer and the structural unit derived from the said polyfunctional monomer can be calculated | required from the preparation amount of the monomer.
The organic fine particles (β) containing the raw material polymer are usually obtained by synthesizing the raw material polymer as fine particles. The production of the raw material polymer fine particles is usually carried out by emulsion polymerization. Examples of the polymerization include a method of polymerizing the polyfunctional monomer and a method of copolymerizing the polyfunctional monomer and a monofunctional monomer.

  In order to obtain the raw material polymer as fine particles, the raw material polymer is usually obtained by emulsion polymerization. Examples of the polymerization initiator that can be used for the synthesis of the raw material polymer include benzoyl peroxide and tert-butyl hydroper Examples thereof include organic peroxides such as oxide, tert-butyl peroxypivalate, cumene hydroperoxide, and organic azo compounds such as azobisisobutyronitrile and azobis- (2,4-dimethyl) valeronitrile.

  Moreover, the thing selected from well-known benzoin ether type compounds, benzophenone compounds, acetophenone compounds, benzyl ketal compounds, bisacyl phosphine oxide compounds etc. as a photoinitiator can be used. These initiators may be used alone or in combination of two or more.

  It is also possible to use known chain transfer agents such as mercaptans for adjusting the degree of polymerization. Furthermore, it is of course possible to improve light resistance and heat resistance by adding generally used antioxidants, ultraviolet absorbers, light stabilizers and the like.

  Although the organic fine particles (β) are usually dispersed in the high refractive index layer, the organic fine particles (β) may contain the raw material polymer, and even if the fine particles have a multilayer structure, the layer structure Fine particles which do not have

  Among them, the organic fine particles (β) are preferably fine particles having a multilayer structure since various functions can be imparted, and more preferably fine particles having a core and a shell, that is, fine particles having a so-called core / shell structure.

  As the fine particles having a core / shell structure, it is preferable from the viewpoint of improving moldability and dispersibility in other resins and solvents that the core is formed from the raw material polymer and the shell is formed from a thermoplastic resin. .

  The thermoplastic resin constituting the shell preferably has excellent compatibility with the binder resin in order to impart dispersibility to the binder resin and the like to the fine particles, specifically, an uncrosslinked thermoplastic resin. It is preferable that

The fine particles having the core-shell structure are excellent in hardness because the core is formed from a raw material polymer having excellent hardness.
When the fine particles are fine particles having no layer structure, the upper limit of the average particle diameter of the fine particles is usually 200 nm or less, and the lower limit thereof is usually 10 nm or more. Within the said range, it is preferable from the point of hardness and transparency.

  When the fine particles have a core-shell structure, the average particle diameter of the core of the fine particles is preferably 200 nm or less, and more preferably 100 nm or less. The above range is preferred because it tends to be more excellent in transparency when a dispersion in which fine particles are dispersed is applied to a support or the like.

  The average particle size of the core is preferably 10 nm or more. Below the above range, the production of the fine particles tends to be difficult, and when a molded body such as a film is obtained by film formation using the particles, the hardness during film formation tends to be inferior.

  When the fine particles have a core / shell structure, the average particle size of the whole fine particles is usually 430 nm or less, preferably 215 nm or less. The average particle size of the entire fine particles is preferably 11 nm or more. The above range is preferable because the dispersibility of the fine particles in the binder or the solvent is good and the transparency tends to be excellent.

  The particle size of the fine particles (the particle size of the core or the particle size including the shell) can be measured using a submicron particle analyzer N4 manufactured by Beckman Coulter, Inc. at the time of producing the fine particles.

  Further, in a molded body such as a film in which fine particles are dispersed in another resin or the like, the shell portion is often difficult to distinguish from other resins, and only the particle size of the core portion can be confirmed. The particle diameter of the core was determined by measuring the maximum diameter (major axis diameter) of 100 fine particles that can be seen at a magnification of 30,000 to 80,000 times using a transmission electron microscope (TEM Hitachi H-7000 100 kV). By calculating the average value of the diameter, the average particle diameter of the core can be obtained.

  When the fine particles have a core-shell structure, the composition ratio of the core to the shell is core / shell = 10/90 to 90/10 (weight ratio), more preferably 30/70 to 70/30 ( Weight ratio).

  The method for producing the organic fine particles (β) is not particularly limited. For example, the method (I) for producing fine particles containing the raw material polymer (organic fine particles (β)) by emulsion polymerization, A method (II) or the like for producing fine particles (organic fine particles (β)) having a core / shell structure by producing fine particles containing coalescence by an emulsion polymerization method and then forming the shell by the emulsion polymerization method using the fine particles as a core. Can be mentioned.

  As a specific example of the method (II), first, the monomer used to obtain the raw material polymer is added to water as a raw material monomer constituting the core together with a surfactant, a polymerization initiator, and the like to emulsify. Polymerization is performed to obtain a raw material polymer. Subsequently, a monomer that forms a shell is added, and emulsion polymerization is performed to obtain fine particles (organic fine particles (β)) having a core-shell structure. If necessary, the fine particles are mixed with another binder resin or the like and molded.

As the surfactant used for emulsion polymerization, nonionic and cationic surfactants can be used in addition to commonly used anionic surfactants. These surfactants may be used alone or in combination of two or more.

  Specific examples of surfactants include anionic surfactants such as fatty acid salts, alkyl sulfonates, and ether phosphates, and nonionic surfactants such as polyoxyethylene alkyl ethers and polyoxyethylene fatty acid esters. Examples of cationic surfactants include alkyl quaternary ammonium salts.

The shell is preferably a non-crosslinked polymer obtained from the following monomers in order for the fine particles to exhibit dispersibility and compatibility in a solvent, a binder resin, and the like.
The monomer for forming the shell is preferably a monofunctional monomer. For example, alkylstyrenes such as styrene, methylstyrene and ethylstyrene, aromatic vinyl compounds such as isopropenylbenzene, benzyl (meth) acrylate, phenoxyethyl ( (Meth) acrylate, isobornyl (meth) acrylate, tert-butyl (meth) acrylate, n-butyl (meth) acrylate, ethyl (meth) acrylate, methyl (meth) acrylate and other (meth) acrylic ester compounds, acrylonitrile, etc. are used be able to. These monofunctional monomers may be used individually by 1 type, and may use 2 or more types.

  As these monofunctional monomers, it is preferable to use an aromatic vinyl monomer that tends to have a low refractive index at least when it is fluorinated. In order to improve the compatibility of fine particles with a solvent or binder, acrylonitrile, ethyl (methacrylate) ) Acrylate, methyl (meth) acrylate, etc. are preferably used in combination with an aromatic vinyl monomer.

  The organic fine particles (β) obtained by the method (I) or the method (II) may be used as they are in an aqueous solution in which the organic fine particles (β) are dispersed, obtained by emulsion polymerization. ) Is preferably recovered as a polymer solid and then redispersed in a solvent or the like.

  The method for recovering the organic fine particles (β) as a polymer solid is not particularly limited, but a method of directly drying the aqueous solution in which the organic fine particles (β) are dispersed, an acid in the aqueous solution in which the organic fine particles (β) are dispersed. Adding and recovering the acid precipitation method, adding a salt to the aqueous solution in which the organic fine particles (β) are dispersed, recovering the salt, freezing the aqueous solution in which the organic fine particles (β) are dispersed, re-dissolving and precipitating Known methods such as a method of collecting and filtering a product, a method of freezing an aqueous solution in which the organic fine particles (β) are dispersed, and a method of collecting by freeze-drying can be used. The obtained polymer solid is used after being redispersed with an appropriate solvent. In addition to the usual stirring method, an ultrasonic wave, a homogenizer, or the like can be used for dispersion.

  The organic fine particles (β) thus obtained can be used as a coating solution by mixing with a binder resin or the like. For example, in the case of obtaining an optical laminate having a low refractive index layer, a high refractive index layer and a support, a coating liquid containing the organic fine particles (β) and a binder resin is prepared, and the liquid is used as a support. After coating on top and forming a coating layer (high refractive index layer) containing organic fine particles (β) and a binder resin, the surface layer portion of the coating layer is treated with fluorine gas, and the following organic fine particles (α) are applied to the surface layer portion. By forming the low-refractive index layer including, an optical laminate having a low-refractive index layer, a high-refractive index layer, and a support can be obtained.

  As another example, the organic fine particles (β) are melt-extruded using an extrusion molding machine or the like to form a film, the surface layer portion of the film is treated with fluorine gas, and the organic fine particles are applied to the surface layer portion. By forming a low refractive index layer containing (α), an optical laminate having a low refractive index layer and a high refractive index layer can be obtained.

(Low refractive index layer)
In the low refractive index layer of the optical layered body of the present invention, organic fine particles are dispersed, and usually the following organic fine particles (α) are dispersed. The low refractive index layer is usually a layer formed by subjecting the high refractive index layer to direct fluorination treatment using fluorine gas. The optical layered body of the present invention can be suitably used as an antireflection film because the outermost layer on at least one surface is a low refractive index layer.

The organic fine particles (α), usually the organic fine particles (β) are obtained by subjecting the organic fine particles (β) to a direct fluorination treatment using fluorine gas.
That is, the organic fine particles (α) are usually at least selected from the group consisting of a crosslinked structure, a chain formed by polymerization of a polymerizable group having a carbon / carbon double bond, and an aromatic ring and an alicyclic ring. And a carbon atom constituting the ring, wherein the chain has at least one fluorine-substituted methylene group selected from the group consisting of a —CF ₂ — group and a —CHF— group. At least a part thereof contains a fluorine-based polymer having fluorine atoms bonded thereto.

  In other words, the organic fine particles (α) are usually selected from the group consisting of a crosslinked structure, a chain formed by polymerization of a polymerizable group having a carbon / carbon double bond, and an aromatic ring and an alicyclic ring. A polymer obtained by subjecting a polymer having at least one ring and a chain having a methylene group (raw material polymer) to direct fluorination treatment using fluorine gas is contained.

  Since the fluorine polymer contains fluorine atoms in the chain and ring, the fluorine polymer has a lower refractive index and excellent light transmittance as compared with conventional fluorine polymers. In addition, the fluoropolymer has a cross-linked structure, and therefore has excellent hardness. Since the organic fine particles (α) containing such a fluoropolymer are dispersed in the low refractive index layer, the optical laminate of the present invention has excellent antireflection properties and hardness.

In the raw material polymer, a hydrogen atom of a methylene group of a chain formed by polymerization of a polymerizable group having a carbon / carbon double bond is substituted by direct fluorination treatment, and a —CF ₂ — group and At least one fluorine-substituted methylene group selected from the group consisting of —CHF— groups, and at least part of carbon atoms constituting at least one ring selected from the group consisting of aromatic rings and alicyclic rings, It is presumed that the atoms are bonded to form a fluoropolymer used in the present invention. In addition, when direct fluorination treatment using fluorine gas is performed on a styrene / divinylbenzene / ethylstyrene copolymer which is a kind of raw material polymer, the peak of aromatic C—H stretching vibration at 3100 to 3000 cm ⁻¹ , methylene C-H stretching vibration peak of 2960～2850Cm ^-1, and aromatic C = C stretching peak of 1610～1490Cm ^-1 vibrations disappeared or attenuation, of the C-F stretching vibration instead 1270～1100Cm ^-1 The peak appears.

  In general, when a polymer is directly fluorinated using fluorine gas, part of the molecular chain of the polymer may be cleaved. However, the raw polymer used in the present invention has a crosslinked structure. Therefore, even if some molecular chains are cleaved, the obtained fluoropolymer does not have a low molecular weight and does not deteriorate the solvent resistance.

  Specific examples of the direct fluorination treatment include a single layer film composed only of a high refractive index layer in which organic fine particles (β) are dispersed, or a laminate having a high refractive index layer in which organic fine particles (β) are dispersed on a support. In order to place the body in a sealed space and perform evacuation in advance to remove oxygen, fluorine gas is introduced into the space, the partial pressure of the fluorine gas is 600 Pa to 1.5 MPa, and the total pressure in the sealed space Is a method of holding for 5 seconds to 1000 minutes under the conditions of 1000 Pa to 1.5 MPa and a temperature of −50 ° C. to 100 ° C.

When introducing the fluorine gas into the sealed space, the fluorine gas may be used alone, or an inert gas such as nitrogen, argon, or helium may be introduced at the same time, or fluorine diluted with these inert gases. Gas may be used. Further, it is preferable to introduce these inert gases after evacuation for the first oxygen removal, and then perform evacuation again because oxygen remaining in the space can be further reduced.

  In the direct fluorination treatment using fluorine gas, at least a part of the hydrogen atoms of the raw material polymer can be substituted with a fluorine atom or added to an aromatic ring, and a fluorine-based polymer can be suitably obtained. .

  Without using direct fluorination treatment, polymerization is performed using a monomer containing fluorine to obtain a fluorine polymer, or a fluorine polymer obtained by chemically introducing fluorine atoms into a raw material polymer is However, it is difficult to produce a very thin film or a molded body having a complicated shape, but the organic fine particles (β) are formed on a single-layer film consisting of only a high refractive index layer in which the organic fine particles (β) are dispersed. In the case of subjecting a laminate having a dispersed high refractive index layer to a fluorine gas treatment, it is possible to introduce fluorine after forming the single layer film or laminate into a desired shape. Only the extreme surface of the layer can be modified to a fluoropolymer (low refractive index layer).

  In the direct fluorination treatment, fluorine gas is a very reactive gas, so that the methylene contained in the organic fine particles (β) dispersed in the high refractive index layer regardless of the position of the hydrogen atom and the reactivity. A hydrogen atom of a group can be substituted with a fluorine atom, a hydrogen atom of an aromatic ring can be substituted with a fluorine atom, or a fluorine atom can be added to an aromatic ring.

(Optical laminate)
The optical layered body of the present invention is a layered body having a low refractive index layer and a high refractive index layer, wherein the outermost layer on at least one surface is the low refractive index layer, and the low refractive index layer and the high refractive index layer. Organic fine particles are dispersed in the layer, and the thickness of the low refractive index layer is 50 to 300 nm. From the surface of the low refractive index layer to the high refractive index layer side, C60 ion gun mounted X-ray photoelectron spectroscopy When the depth direction analysis is performed by the analysis method, the molar ratio (F / C) of the abundance of fluorine and carbon at a depth of 40 nm is 0.2 or more.

  The molar ratio (F / C) of the abundance of fluorine and carbon at a depth of 40 nm is a balance between the total amount of fluorine introduced, the C—H number in the raw material polymer, and the diffusion of fluorine in the case of direct fluorination treatment. From a viewpoint, it is 0.2-2 normally, Preferably it is 0.3-1.75.

  If the molar ratio (F / C) of the abundance of fluorine and carbon at a depth of 40 nm is within the above range, the optical layered body of the present invention is highly crosslinked in the vicinity of the surface (depth of 40 nm). Organic fine particles containing a large amount of fluorine having a hardness are dispersed, usually having a crosslinked structure, and further containing organic fine particles (β) containing the raw material polymer having a high hardness in the high refractive index layer. Therefore, it has a low-refractive index layer and a high-refractive index layer with high hardness and can be suitably used as an antireflection film.

As described above, the organic fine particles (β) are preferably dispersed in the high refractive index layer, and the organic fine particles (α) are preferably dispersed in the low refractive index layer.
The shape of the optical layered body of the present invention is usually a film or a sheet.

In the optical layered body of the present invention, the low refractive index layer and the high refractive index layer are collectively referred to as an antireflection layer.
In the optical layered body of the present invention, an antireflection layer may be formed on a support, or may be formed only of an antireflection layer that does not have a support.

As a method for producing the optical layered body of the present invention, the high refractive index layer is formed on a support, the surface layer portion of the high refractive index layer is subjected to fluorine gas treatment, and the low refractive index layer is formed on the surface layer portion. It is preferable.

  In particular, after forming the high refractive index layer by applying a coating liquid containing the organic fine particles (β) and the binder resin on the support, the surface layer portion of the high refractive index layer is subjected to fluorine gas treatment, It is preferable to form a low refractive index layer in the portion from the viewpoint of the hardness of the obtained low refractive index layer, the adhesion between the support and the antireflection layer, and the uniformity of the film pressure of the antireflection layer.

In addition, as a material of the support, resin, glass, metal, metal compound, ceramics, or the like can be used. Among these, transparent resin and glass are preferable.
Examples of the resin include polyethylene terephthalate, polyether sulfone, polyester, polyacrylic resin, polyvinyl alcohol, polycarbonate, triacetyl cellulose, diacetyl cellulose, polyacrylonitrile, and the like.

The thickness of the support is usually 1 μm to 1 mm, preferably 10 to 200 μm, although it varies depending on the material of the support.
The binder resin is preferably a UV curable resin that can uniformly disperse the fine particles before the fluorine gas treatment and can form a coating film. When a UV curable resin is used as the binder resin, the high refractive index layer is usually formed by curing the UV curable resin by UV irradiation after applying the coating liquid on the support.

  Examples of the UV curable resin include acrylic resins such as urethane (meth) acrylate, epoxy (meth) acrylate, and polyfunctional (meth) acrylate, unsaturated polyester resins, and epoxy resins. ) Acrylic resin mainly composed of acrylate is preferable in consideration of decomposition during the fluorination reaction. In addition, a resin containing a fluorine atom in advance can be used for these resins. These UV curable resins may be used alone or in combination of two or more. These UV curable resins are used in combination with a photopolymerization initiator, a photopolymerization accelerator, or the like for suitably exhibiting UV curability in addition to the resin.

  When a coating solution using a UV curable resin as a binder resin is used for forming a high refractive index layer, organic fine particles (β) contained in the coating solution (organic fine particles (β) having a core-shell structure) In this case, the weight ratio of the core part) to the UV curable resin is usually 10 to 3600 parts by weight, preferably 20 to 1000 parts by weight of the UV curable resin per 100 parts by weight of the organic fine particles (β). is there.

  Examples of the method for applying the coating solution on the support include coating methods such as curtain float coating, dipping, roll coating, bar coating, spin coating, and spray coating.

  As a method for producing an optical laminate formed only of an antireflection layer, a film (high refractive index layer) formed from the organic fine particles (β) or a composition containing the organic fine particles (β) is produced, and fluorine is produced. A method of forming a low refractive index layer containing a highly transparent fluororesin on the surface layer of the film by gas treatment can be mentioned. Examples of the method for forming the film (high refractive index layer) include a method of forming organic fine particles (β) into a film by extrusion molding.

  In the optical layered body in which the antireflection layer is formed on the support, the thickness of the low refractive index layer is usually 50 to 300 nm, preferably 80 to 280 nm. Moreover, a high refractive index layer is 0.1-25 micrometers, Preferably it is 0.5-20 micrometers.

  In the optical layered body formed only from the antireflection layer, the thickness of the low refractive index layer containing the highly transparent fluororesin is usually 50 to 300 nm, preferably 80 to 280 nm. Moreover, a high refractive index layer is 0.1-500 micrometers, Preferably it is 10-350 micrometers.

In the optical layered body of the present invention, since the thickness of the low refractive index layer is within the above range, reflection in the visible light region is efficiently suppressed with an appropriate amount of fluorine.
The thickness of each layer can be measured with a transmission electron microscope (TEM, for example, H-7000 100 kV manufactured by Hitachi, Ltd.).

  The thickness of the low refractive index layer can be specifically measured as follows. A cross section of the film can be photographed using a transmission electron microscope, and the thickness of the low refractive index layer can be determined from the image. In the transmission electron microscope image, since fluorine has a high electron density, the contrast between the low refractive index layer and the high refractive index layer that does not contain the fluororesin can be recognized and confirmed.

  The low refractive index layer containing the organic fine particles (α) included in the optical layered body of the present invention is excellent in hardness. Specifically, in accordance with JIS K-5600-5-4 of the low refractive index layer, the pencil hardness measured under a 1 kg condition is usually 2H or higher, preferably 3H or higher.

EXAMPLES Next, although an Example is shown and this invention is demonstrated further in detail, this invention is not limited by these.
[Production Example 1] Production of organic fine particles having a core-shell structure (Production of core)
A glass container was charged with 180 g of pure water, 0.6 g of a 1 wt% aqueous sodium ethylenediaminetetraacetate dihydrate solution, 6 g of a 1% tartaric acid aqueous solution, stirred, and blown with nitrogen.

  The glass container was heated to 70 ° C. in a hot water bath and then mixed with nitrogen (14.3 g of styrene and 15.7 g of 57% by weight divinylbenzene) and 5% sodium alkyldiphenyl ether disulfonate as a surfactant. 40 g of an aqueous solution was added, mixed in a nitrogen atmosphere, and the temperature was raised to 70 ° C.

Then, 16.8 g of 5% tert-butyl hydroperoxide aqueous solution and 16.8 g of 5% sodium formaldehyde sulfoxylate aqueous solution were added as polymerization initiators, and polymerization was carried out at 70 ° C. in a nitrogen atmosphere. Two hours later, 8.4 g of 5% tert-butyl hydroperoxide aqueous solution, 8.4 g of 5% sodium formaldehyde sulfoxylate aqueous solution, and 20 g of 5% sodium alkyldiphenyl ether disulfonate aqueous solution were added, and 5% after 4 hours. An additional 8.4 g of tert-butyl hydroperoxide aqueous solution and 8.4 g of 5% sodium formaldehyde sulfoxylate were added to continue the polymerization reaction, and after 6 hours, the polymerization was terminated to obtain a fine particle dispersed aqueous solution.

The particle size of the fine particles in the fine particle dispersed aqueous solution at the end was 36 nm. The particle size was measured using a submicron particle analyzer N4 manufactured by Beckman Coulter.
(Manufacture of organic fine particles)
The aqueous fine particle dispersion prepared in the production of the core was heated to 70 ° C., and 9.65 g of styrene previously substituted with nitrogen, 3.22 g of acrylonitrile, 0.05 g of n-dodecyl mercaptan, and a 50% aqueous solution of diisopropylbenzene hydroperoxide were added. 13 g was added, and 5.2 g of 5% tert-butyl hydroperoxide aqueous solution and 5.2 g of 5% sodium formaldehyde sulfoxylate were added under a nitrogen atmosphere to carry out a polymerization reaction. After 2 hours, an additional 2.6 g of 5% tert-butyl hydroperoxide aqueous solution and 2.6 g of 5% sodium formaldehyde sulfoxylate were added to continue the polymerization. After 4 hours, the polymerization was terminated by cooling. A fine particle dispersed aqueous solution containing organic fine particles having a shell structure was obtained. The particle size of the organic fine particles in the fine particle dispersed aqueous solution at the end of the polymerization was 48 nm. The particle size was measured using a submicron particle analyzer N4 manufactured by Beckman Coulter.

The weight ratio of the core to the shell (core / shell) was 30 / 12.87 (70/30) based on the amount of monomer used.
(Salting out organic fine particles)
200 g of the fine particle dispersion prepared in the production of the organic fine particles was dropped into 200 g of a 3% calcium chloride aqueous solution at 90 ° C., and salting out was performed. Next, the precipitate was filtered, washed with water, and dried at 40 ° C. to obtain a white powder (organic fine particles).

[Production Example 2] Production of organic fine particles having a core-shell structure (Production of core)
A glass container was charged with 900 g of pure water, 3.1 g of a 1 wt% sodium ethylenediaminetetraacetate dihydrate aqueous solution, 30.0 g of a 1% tartaric acid aqueous solution, stirred, and nitrogen was blown into the glass container.

  The glass container was heated to 70 ° C. in a hot water bath and then mixed with nitrogen (71.3 g of styrene and 78.7 g of 57% by weight divinylbenzene) and 5% sodium alkyldiphenyl ether disulfonate as a surfactant. 150 g of an aqueous solution was added, mixed in a nitrogen atmosphere, and the temperature was raised to 70 ° C.

  Next, 42.0 g of 5% tert-butyl hydroperoxide aqueous solution and 42.0 g of 5% sodium formaldehyde sulfoxylate aqueous solution were added as a polymerization initiator, and polymerization was carried out at 70 ° C. in a nitrogen atmosphere. After 2 hours, 42.0 g of 5% tert-butyl hydroperoxide aqueous solution and 42.0 g of 5% sodium formaldehyde sulfoxylate aqueous solution were added, and 42.0 g of 5% tert-butyl hydroperoxide aqueous solution was added 4 hours later. An additional 42.0 g of 5% sodium formaldehyde sulfoxylate was added to continue the polymerization reaction, and after 6 hours, the polymerization was terminated by cooling to obtain a fine particle dispersed aqueous solution.

The particle size of the fine particles in the fine particle-dispersed aqueous solution at the end was 131 nm. The particle size was measured using a submicron particle analyzer N4 manufactured by Beckman Coulter.
(Manufacture of organic fine particles)
The aqueous fine particle dispersion prepared in the production of the core was heated to 70 ° C., and 131.3 g of styrene previously substituted with nitrogen, 43.8 g of acrylonitrile, 0.35 g of n-dodecyl mercaptan, 50% diisopropylbenzene hydroperoxide aqueous solution 1. 75 g was added, and further 70.7 g of 5% tert-butyl hydroperoxide aqueous solution and 70.0 g of 5% sodium formaldehyde sulfoxylate were added under a nitrogen atmosphere to carry out the polymerization reaction. After 2 hours, 131.3 g of styrene, 43.8 g of acrylonitrile, 0.35 g of n-dodecyl mercaptan, 1.75 g of 50% diisopropylbenzene hydroperoxide aqueous solution, 70.7 g of 5% tert-butyl hydroperoxide aqueous solution, 5% sodium The polymerization was continued by adding 70.0 g of formaldehyde sulfoxylate, followed by cooling after 4 hours to complete the polymerization, and a fine particle dispersed aqueous solution containing organic fine particles having a core / shell structure was obtained. The particle size of the organic fine particles in the fine particle dispersed aqueous solution at the end of the polymerization was 162 nm. The particle size was measured using a submicron particle analyzer N4 manufactured by Beckman Coulter.

The weight ratio of the core to the shell (core / shell) was 30/70 based on the amount of monomer used.
(Salting out organic fine particles)
200 g of the fine particle-dispersed aqueous solution prepared in the production of the organic fine particles was dropped into 400 g of a 0.5% calcium chloride aqueous solution at 90 ° C. for salting out. Next, the precipitate was filtered, washed with water, and dried at 40 ° C. to obtain 44 g of white powder (organic fine particles).

[Production Example 3] Preparation of UV-curable hard coat solution 80 g of dipentaerythritol hexaacrylate, 20 g of 2,2-bis [4- (meth) acryloxyethoxyphenyl] propane, 2,2-dimethoxy-1,2-diphenyl Ethanol-1-one (3 g) and methyl isobutyl ketone (100 g) were mixed to prepare an ultraviolet curable hard coat solution (solid content: 50%).

[Production Example 4] Preparation of hard coat liquid containing organic fine particles having core / shell structure Organic fine particles having core / shell structure obtained in Production Example 1 (core / shell ratio = 70/30 (weight ratio)) ) And the ultraviolet curable hard coat solution obtained in Production Example 3 were prepared so that the core / shell / ultraviolet curable hard coat solution (solid content) = 233/100/100 (parts by weight). Obtained (core / ultraviolet curable hard coat liquid (solid content) = 100/43 (parts by weight)).

Next, the coating solution was prepared with a solvent methyl isobutyl ketone (Wako Pure Chemical Industries) to a solid content of 20 wt% to obtain a hard coating solution containing organic fine particles having a core-shell structure.
[Production Example 5] Preparation of hard coat liquid containing organic fine particles having core / shell structure Organic fine particles having core / shell structure obtained in Production Example 2 (core / shell ratio = 30/70 (weight ratio)) ) And the ultraviolet curable hard coat solution obtained in Production Example 3 were prepared so that the core / shell / ultraviolet curable hard coat solution (solid content) = 43/100/30 (parts by weight). Obtained (core / ultraviolet curable hard coat liquid (solid content) = 100/70 (parts by weight)).

Next, the coating solution was prepared with a solvent methyl isobutyl ketone (Wako Pure Chemical Industries) to a solid content of 20 wt% to obtain a hard coating solution containing organic fine particles having a core-shell structure.
[Comparative Example 1]
The hard coat liquid containing organic fine particles having the core / shell structure of Production Example 4 was applied onto a transparent PET (Tetron Film HS-74, Teijin DuPont Films) substrate by bar coating, and dried with a dryer. Methyl isobutyl ketone solvent is blown off, UV
Irradiation (800 mJ / cm ² ) was performed to form a film (thickness 10 μm), and a film having a layer structure of base material / high refractive index layer was obtained.

[Example 1]
Two films having the layer structure of the base material / high refractive index layer obtained in Comparative Example 1 were prepared, the base material surfaces of the film were overlapped, and the end portion was subjected to seal pressure (Cute Sealer manufactured by Fuji Impulse). Used and heat-sealed.

  Fluorine gas (total pressure 93,000 Pa, fluorine partial pressure 7000 Pa) mixed with nitrogen after putting the film in which the substrates are fused together into a fluorine gas processing chamber and sufficiently evacuating to remove oxygen Fluorine gas treatment is performed for 10 minutes at room temperature in an atmosphere, a low refractive index layer is formed on the surface layer of the high refractive index layer, and the fused ends are separated, and the base material / high refractive index layer / low refractive index is formed. Two antireflective films having a layer structure of rate layers were obtained.

  The obtained antireflection film has a low refractive index layer formed with a thickness of 250 nm (see FIG. 1) in cross-sectional observation with a transmission electron microscope, and fine particles are formed on the low refractive index layer and the high refractive index layer. The particle diameter of the core of the fine particles was 40 nm (see FIG. 2).

Fluorine at a depth of 40 nm when the depth direction analysis was performed from the surface of the low refractive index layer of the obtained antireflection film to the high refractive index layer side by C60 ion gun mounted X-ray photoelectron spectroscopy. The molar ratio (F / C) of the abundance of carbon and carbon was 0.66.

  Further, the light transmittance was 88.8% before the direct fluorination treatment (Comparative Example 1) and 92.9% after the direct fluorination treatment (Example 1), and the transparency was improved. Further, the reflectance was 5.9% before the direct fluorination treatment (Comparative Example 1) and 1.8% after the direct fluorination treatment (Example 1), and the antireflection property was also improved.

[Comparative Example 2]
The hard coat liquid containing organic fine particles having the core / shell structure of Production Example 5 was applied onto a transparent PET (Tetron Film HS-74, Teijin DuPont Films) substrate by bar coating, and dried with a dryer. Methyl isobutyl ketone solvent is blown off, UV
Irradiation (800 mJ / cm ² ) was performed to form a film (thickness 10 μm), and a film having a layer structure of base material / high refractive index layer was obtained.

[Example 2]
Two films having the layer structure of the base material / high refractive index layer obtained in Comparative Example 2 are prepared, the base material surfaces of the film are overlapped, and the end portion is subjected to seal pressure (Cute Sealer manufactured by Fuji Impulse). Used and heat-sealed.

  Fluorine gas (total pressure 93000 Pa, fluorine partial pressure 1500 Pa) mixed with nitrogen after putting the film in which the substrates are fused together into a fluorine gas processing chamber and sufficiently evacuating to remove oxygen Fluorine gas treatment is performed for 25 minutes at room temperature in an atmosphere, a low refractive index layer is formed on the surface layer of the high refractive index layer, and the fused end is separated, and the base material / high refractive index layer / low refractive index is formed. Two antireflective films having a layer structure of rate layers were obtained.

In the obtained antireflection film, the low refractive index layer was formed with a thickness of 100 nm in cross-sectional observation with a transmission electron microscope.
Fluorine and carbon at a depth of 40 nm when the depth direction analysis was performed from the surface of the low refractive index layer of the obtained antireflection film to the high refractive index layer side by C60 ion gun mounted X-ray photoelectron spectroscopy. The molar ratio (F / C) of the abundance was 0.81.

  The light transmittance was 89.1% before the direct fluorination treatment (Comparative Example 2) and 90.5% after the direct fluorination treatment (Example 2), and the transparency was improved. Moreover, the reflectance was 3.7% before direct fluorination treatment (Comparative Example 2) and 2.3% after direct fluorination treatment (Example 2), and the antireflection property was also improved.

[Comparative Example 3]
Mixing 80 g of dipentaerythritol hexaacrylate, 20 g of 2,2-bis [4- (meth) acryloxyethoxyphenyl] propane, 3 g of 2,2-dimethoxy-1,2-diphenylethane-1-one, and 400 g of methyl isobutyl ketone Thus, an ultraviolet curable hard coat solution (solid content 20%) was prepared.

The UV curable hard coat solution (solid content 20%) is coated on a transparent PET (Tetron Film HS-74, Teijin DuPont Films) substrate by bar coating, and the methyl isobutyl ketone solvent is removed by drying with a dryer. , UV irradiation (800 mJ / cm ² ) was performed to form a film (thickness 10 μm), and a film having a layer structure of base material / high refractive index layer was obtained.

  Two films having the layer structure of the base material / high refractive index layer are prepared, the base material surfaces of the film are overlapped, and the ends thereof are heat-sealed using seal pressure (Cute Sealer manufactured by Fuji Impulse). did.

  Fluorine gas (total pressure 93000 Pa, fluorine partial pressure 1500 Pa) mixed with nitrogen after putting the film in which the substrates are fused together into a fluorine gas processing chamber and sufficiently evacuating to remove oxygen Fluorine gas treatment is performed for 25 minutes at room temperature in an atmosphere, a low refractive index layer is formed on the surface layer of the high refractive index layer, and the fused end is separated, and the base material / high refractive index layer / low refractive index is formed. Two antireflective films having a layer structure of rate layers were obtained.

In the obtained antireflection film, the low refractive index layer was formed with a thickness of 30 nm in cross-sectional observation with a transmission electron microscope.
Fluorine and carbon at a depth of 40 nm when the depth direction analysis was performed from the surface of the low refractive index layer of the obtained antireflection film to the high refractive index layer side by C60 ion gun mounted X-ray photoelectron spectroscopy. And the molar ratio (F / C) of the abundance was 0.004.

The light transmittance was 89.3% after direct fluorination (Comparative Example 3). Further, the reflectance was 5.4% after direct fluorination treatment (Comparative Example 3).
[Evaluation of film]
The following evaluation was performed about the film obtained by the Example and the comparative example.

(Hardness (pencil hardness) measurement)
Using a scratch coating film hardness tester (Toyo Seiki), according to JIS K-5600-5-4, the load is 1 kg under the conditions using pencils H to 9H (Mitsubishi pencil). The hardness of the refractive index layer, the high refractive index layer in Comparative Examples 1 and 2, and the low refractive index layer in Comparative Example 3 was determined based on whether or not the scratch was scratched.

(Light transmittance measurement)
The light transmittance (%) of the film at a wavelength of 300 to 1200 nm was measured using a Hitachi spectrophotometer U4000.

(Measurement of the thickness of the low refractive index layer and the molar ratio (F / C) of the abundance of fluorine and carbon)
The molar ratio (F / C) of the abundance of fluorine and carbon can be measured by the following method.
First, the cross section of the optical laminated body (sample) was image | photographed using the transmission electron microscope (TEM Hitachi Ltd. H-7000 100kV), and the thickness of the low refractive index layer was calculated | required from the image.

  In addition, since fluorine has a high electron density, a layer containing fluorine and a layer not containing fluorine are darker than a layer not containing a fluorine-containing layer. The thickness of the low refractive index layer was confirmed by an electron microscope image.

Next, a C60 ion gun mounted X-ray photoelectron spectrometer (C60-XPS, Quan
Using tera SXM (manufactured by PHI), the optical laminate (sample) is analyzed in the depth direction, and the F1s peak area and the C1s peak area are measured.

By dividing the F1s peak area and the C1s peak area by the relative sensitivity coefficient (RSF), a quantitative value of fluorine and a quantitative value of carbon indicating the abundance of fluorine and carbon are calculated. The ratio between the quantitative value of fluorine and the quantitative value of carbon (the quantitative value of fluorine / the quantitative value of carbon) is the molar ratio (F / C) of the abundance of fluorine and carbon.
At this time, the sputtering rate of C60 was set to 2 nm / min. However, the sputtering speed is a speed when the SiO ₂ is shaved.

Using the thickness of the low refractive index layer obtained from the transmission electron microscope image, the sputtering rate of the sample was calculated as follows.
Using a C60 ion gun mounted X-ray photoelectron spectrometer, the time when the molar ratio (F / C) of the abundance of fluorine and carbon is less than 0.1 when the depth direction analysis is performed on the sample is x (Min), the thickness of the low refractive index layer obtained from the transmission electron microscope image was y (nm), and the sputtering rate was calculated as y / x (nm / min).

Based on the sputtering rate (y / x (nm / min)), the molar ratio (F / C) of the abundance of fluorine and carbon at a depth of 40 nm was determined.
In addition, the measurement conditions at the time of performing a depth direction analysis using a C60 ion gun mounting X-ray photoelectron spectrometer are as follows.
X-ray source: Monochromated Al (1486.6 eV)
Detection area: 100 μmφ
Extraction angle: 45deg
Detection depth: 4-5nm
Sputtering conditions: ion species C ₆₀ + acceleration voltage 10 kV
Sputtering speed: about 2 nm / min (SiO ₂ equivalent value)
F1s relative sensitivity coefficient: 110.554
C1s relative sensitivity coefficient: 34.191
(Reflectance measurement)
Measurement sample that does not cause reflection on other than the reflection measurement surface by roughening the opposite surface of the reflection measurement surface of the evaluation film with # 1200 water-resistant abrasive paper and then painting with an opaque marker using pigment ink It was created. The reflectance was measured by setting this measurement sample to a spectrophotometer U4000 manufactured by Hitachi with a specular reflection accessory attached at 5 degrees.

From Table 1, an optical laminate excellent in light transmittance, reflectance and hardness by directly fluorinating a film (Comparative Examples 1 and 2) having a high refractive index layer in which fine particles containing a raw material polymer are dispersed. It turns out that a body (Examples 1, 2) is obtained.

2 is a TEM image showing the results of cross-sectional observation of the antireflection film obtained in Example 1 using a transmission electron microscope. 2 is a TEM image showing the results of cross-sectional observation of the antireflection film obtained in Example 1 using a transmission electron microscope.

Claims (5)

A laminate having a low refractive index layer and a high refractive index layer,
The outermost layer on at least one surface is the low refractive index layer, organic fine particles are dispersed in the low refractive index layer and the high refractive index layer, and the thickness of the low refractive index layer is 50 to 300 nm. ,
The molar amount of fluorine and carbon at a depth of 40 nm when a depth direction analysis is performed from the surface of the low refractive index layer to the high refractive index layer side by a C60 ion gun mounted X-ray photoelectron spectroscopy. An optical laminate having a ratio (F / C) of 0.2 or more. Organic fine particles (α) are dispersed in the low refractive index layer,
At least one selected from the group consisting of a crosslinked structure, a chain formed by polymerizing a polymerizable group having a carbon / carbon double bond, and an aromatic ring and an alicyclic ring on the organic fine particles (α). Having a ring,
At least one selected from the group consisting of a —CF ₂ — group and a —CHF— group;
Having a kind of fluorine-substituted methylene group;
2. The optical laminate according to claim 1, wherein a fluorine-based polymer in which a fluorine atom is bonded to at least a part of carbon atoms constituting the ring is contained. Organic fine particles (α) are dispersed in the low refractive index layer,
At least one selected from the group consisting of a crosslinked structure, a chain formed by polymerizing a polymerizable group having a carbon / carbon double bond, and an aromatic ring and an alicyclic ring on the organic fine particles (α). A polymer obtained by subjecting a polymer having a ring and a chain having a methylene group (raw material polymer) to direct fluorination treatment using fluorine gas is contained. Item 2. The optical laminate according to Item 1. Organic fine particles (β) are dispersed in the high refractive index layer,
At least one selected from the group consisting of a crosslinked structure, a chain formed by polymerizing a polymerizable group having a carbon / carbon double bond, and an aromatic ring and an alicyclic ring on the organic fine particles (β). The optical layered product according to claim 1, further comprising a polymer having a ring and the chain having a methylene group (raw material polymer).   The optical laminate according to any one of claims 1 to 4, wherein the high refractive index layer and the low refractive index layer are provided on a support.