JP2005157037A - Antireflection film, polarizing plate and image display apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an antireflection film which realizes lower reflectance, by incorporating a low refractive index layer as a layer configuration containing silica fine particles having a porous or hollow inner portion, which has superior film strength, uneveness properties and contamination preventing property of the film surface, and which is to be used for a liquid crystal display apparatus. <P>SOLUTION: The antireflection film is produced, by disposing a hard coat layer essentially comprising an active energy ray curing resin on a transparent film and further disposing a (low refractive index) layer directly or indirectly on the hard coat layer. The low refractive index layer has 1.20 to 1.42 refractive index and contains at least three components of: (A) composite particles, comprising porous particles and a coating layer applied on the surfaces of the porous particles, or hollow particles having the inside filled with a solvent, gas or a porous substance; (B) a binder component; and (C) a nonionic surfactant having a hydrophobic group, comprising dimethylpolysiloxane and a hydrophilic group comprising polyoxyalkylene. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an antireflection film, a polarizing plate using the antireflection film, and an image display device.

  Porous or hollow inside, composite particles having porous particles and a coating layer provided on the surface of the porous particles having a lower refractive index, or solvent, gas, or porous substance inside The silica-based fine particles that are the filled hollow particles are used in Patent Document 1, Patent Document 2, and Patent Document 3 for a low refractive index layer that is an antireflection layer due to optical interference of the antireflection film. It is known to further reduce the refractive index by further reducing the refractive index. However, the antireflective film is used, for example, on the outermost surface of a liquid crystal display device. It was found that the performance was insufficient for all of the film strength, unevenness, and antifouling property of the film surface.

  On the other hand, in JP-A-9-145903, a surfactant is added to a low refractive index layer mainly composed of an ionizing radiation curable resin composition containing ultrafine particles having a refractive index of 1.3 to 1.45. Among the agents, it is known that a fluorine-based polymer is particularly preferable in terms of antifouling and stability, but there is a disadvantage that the film strength and unevenness are insufficient.

An antireflection film with a reduced reflectance, including a low refractive index layer containing silica-based fine particles having a lower refractive index, which is porous or hollow inside, and has a reduced film strength and unevenness. An antireflection film having sufficient performance for all the antifouling properties of the film surface has not yet been found.
Japanese Patent Laid-Open No. 2001-167637 JP 2001-233611 A JP 2002-79616 A

  The present invention includes a low-refractive index layer containing silica-based fine particles having a porous or hollow interior as a layer structure, and has improved film strength, unevenness, and antifouling property on the film surface. An object of the present invention is to provide an antireflection film for use as a liquid crystal display device.

It has been found that the above object of the present invention is achieved by the following means.
(Claim 1)
A refractive index containing at least the following three components (A), (B), and (C) directly or indirectly on a hard coat layer by providing a hard coat layer mainly composed of an active energy ray-curable resin on a transparent film. Provided with a (low refractive index) layer in the range of 1.20 to 1.42.
(A) Composite particles having porous particles and a coating layer provided on the surface of the porous particles, or hollow particles filled with a solvent, gas, or porous substance inside (B) binder component (C) hydrophobic group Is a nonionic surfactant composed of dimethylpolysiloxane and hydrophilic group polyoxyalkylene (Claim 2).
The antireflective film according to claim 1, wherein the binder component represented by (B) is formed by a sol-gel method by hydrolysis polycondensation of alkoxysilane.
(Claim 3)
The antireflection film according to claim 2, wherein 50% by mass or more of the alkoxysilane is tetraethoxysilane.
(Claim 4)
The hard coat layer contains an active energy ray-curable resin component and metal oxide fine particles as main components, and the low refractive index layer is provided directly on the hard coat layer. The antireflection film according to any one of the above.
(Claim 5)
5. The hard coat layer contains a nonionic surfactant composed of dimethylpolysiloxane as a hydrophobic group represented by (C) and a polyoxyalkylene as a hydrophilic group. Antireflection film.
(Claim 6)
The hard coat layer contains metal oxide fine particles selected from Zr, Sn, Sb, As, Zn, Nb, In, and Al, according to any one of claims 1 to 5. Antireflection film.
(Claim 7)
A nonionic surfactant composed of dimethylpolysiloxane having a hydrophobic group represented by (C) and a polyoxyalkylene having a hydrophilic group is a linear form in which dimethylpolysiloxane and polyoxyalkylene are alternately and repeatedly bonded. The antireflection film according to claim 1, wherein the antireflection film is a block copolymer of the following.
(Claim 8)
The hard coat layer is composed of two or more layers, and at least one of an antistatic agent, a visible light region color tone adjusting agent, an electromagnetic wave blocking agent, and an infrared absorber is added to one of the layers. The antireflection film according to any one of claims 1 to 7.
(Claim 9)
The antireflection film according to any one of claims 1 to 8, wherein the hard coat layer contains antiglare fine particles having a particle size of 0.1 to 1.0 µm.
(Claim 10)
In the case of having a high refractive index layer, or a middle refractive index layer and a high refractive index layer between the hard coat layer and the low refractive index layer, the layer in contact with the low refractive index layer is represented by (C). The antireflective film of any one of Claims 1-4 and 6-9 characterized by the above-mentioned.
(Claim 11)
A polarizing plate using the antireflection film according to claim 1.
(Claim 12)
An image display device using the antireflection film according to claim 1.

  According to the present invention, an antireflection film suitable for a liquid crystal display device having a reduced reflectance, excellent film strength, unevenness, and antifouling property on the film surface can be obtained.

  Hereinafter, the best mode for carrying out the present invention will be described, but the present invention is not limited thereto.

  As a result of intensive studies, the present inventor has mainly used an active energy ray curable resin provided on a transparent film in order to reduce the reflectance and obtain an antireflection film excellent in film strength, unevenness, and antifouling property of the film surface. A non-ionic system composed of hollow spherical silica-based fine particles having a porous or hollow interior on a hard coat layer as a component, a binder component, dimethylpolysiloxane with a hydrophobic group, and polyoxyalkylene with a hydrophilic group It has been found that providing a low refractive index layer containing a surfactant as a component gives very favorable results, and in particular for the binder component, a synergistic effect is obtained when using an alkoxysilane compound, which is very effective. I found out. In addition, various compounds generally known as surfactants are not effective, and are particularly preferable only when the nonionic surfactant of the present invention is used.

  The antireflection film of the present invention is a composite particle having a porous particle and a coating layer provided on the surface of the porous particle, which is porous or hollow inside on a transparent film, or a solvent, gas inside Or an antireflection film provided with an antireflection layer including a low refractive index layer containing hollow particles filled with a porous material.

  For composite particles having porous particles and a coating layer provided on the surface of the porous particles, or hollow particles filled with a solvent, gas, or porous substance, as described above, JP-A-2001-167737, As described in JP-A-2001-233611, JP-A-2002-79616, etc., the refractive index of the low-refractive index layer is further reduced by using it as a low-refractive index layer that is an antireflection layer due to optical interference of the antireflection film. It is known to reduce the luminous reflectance.

  In a normal configuration of the antireflection film, a low refractive index layer is provided on a hard coat layer mainly composed of an active energy ray curable resin provided on a transparent film. In addition, the antireflection film is applied to the outermost surface of, for example, a liquid crystal display device, so that these porous particles and composite particles having a coating layer provided on the surface of the porous particles, or a solvent inside, If a low refractive index layer is formed by containing hollow particles filled with gas or a porous material, the film strength of the low refractive index layer is insufficient, unevenness is likely to occur, and the surface is more likely to become dirty. There were drawbacks.

  By using such hollow spherical silica-based fine particles together with a specific binder component and a specific surfactant, the present inventors can obtain a low refractive index layer in which the above disadvantages are eliminated. I found it.

In the antireflection film according to the present invention, a low refractive index layer having a refractive index of 1.20 to 1.42 containing at least the following three components is provided on a transparent film.
(A) Composite particles having porous particles and a coating layer provided on the surface of the porous particles, or hollow particles filled with a solvent, gas, or porous substance inside (B) binder component (C) hydrophobic group Is a nonionic surfactant composed of dimethylpolysiloxane and a hydrophilic group composed of polyoxyalkylene.

  The composite particles having the porous particles represented by (A) and the coating layer provided on the surface of the porous particles, or the hollow particles filled with a solvent, gas, or porous substance will be described.

  The inorganic fine particle is (I) a composite particle comprising a porous particle and a coating layer provided on the surface of the porous particle, or (II) a cavity inside, and the content is a solvent, a gas or a porous substance It is a hollow particle filled with. The low refractive index layer may contain either (I) composite particles or (II) hollow particles, or may contain both.

  The hollow particles are particles having cavities inside, and the cavities are surrounded by particle walls. The cavity is filled with a content such as a solvent, a gas, or a porous material used at the time of preparation. It is desirable that the average particle diameter of such inorganic fine particles is in the range of 5 to 300 nm, preferably 10 to 200 nm. The inorganic fine particles used are appropriately selected according to the thickness of the transparent film to be formed, and may be in the range of 2/3 to 1/10 of the film thickness of the transparent film such as the low refractive index layer to be formed. desirable. These inorganic fine particles are preferably used in a state of being dispersed in an appropriate medium in order to form a low refractive index layer. As the dispersion medium, water, alcohol (for example, methanol, ethanol, isopropyl alcohol), ketone (for example, methyl ethyl ketone, methyl isobutyl ketone), and ketone alcohol (for example, diacetone alcohol) are preferable.

  The thickness of the coating layer of the composite particles or the thickness of the particle walls of the hollow particles is desirably in the range of 1 to 20 nm, preferably 2 to 15 nm. In the case of composite particles, if the thickness of the coating layer is less than 1 nm, the particles may not be completely covered, and silicate monomers and oligomers with a low degree of polymerization, which are coating liquid components described later, are easy. In some cases, the inside of the composite particle enters the inside and the porosity of the inside is reduced, so that the effect of the low refractive index cannot be sufficiently obtained. When the thickness of the coating layer exceeds 20 nm, the silicic acid monomer and oligomer do not enter the inside, but the porosity (pore volume) of the composite particles is lowered and the effect of low refractive index is sufficiently obtained. It may not be possible. In the case of hollow particles, if the particle wall thickness is less than 1 nm, the particle shape may not be maintained, and even if the thickness exceeds 20 nm, the effect of low refractive index may not be sufficiently exhibited. is there.

The coating layer of the composite particles or the particle wall of the hollow particles is preferably composed mainly of silica. The coating layer of the composite particle or the particle wall of the hollow particle may contain a component other than silica, specifically, Al ₂ O ₃ , B ₂ O ₃ , TiO ₂ , ZrO ₂ , SnO _2. and _{CeO 2, P 2 O 3,} Sb 2 O 3, MoO 3, ZnO 2, WO 3 and the like. Examples of the porous particles constituting the composite particles include those made of silica, those made of silica and an inorganic compound other than silica, and those made of CaF ₂ , NaF, NaAlF ₆ , MgF, and the like. Among these, porous particles made of a composite oxide of silica and an inorganic compound other than silica are particularly preferable. Examples of inorganic compounds other than silica include Al ₂ O ₃ , B ₂ O ₃ , TiO ₂ , ZrO ₂ , SnO ₂ , CeO ₂ , P ₂ O ₃ , Sb ₂ O ₃ , MoO ₃ , ZnO ₂ , WO _{3 and the} like. 1 type or 2 types or more can be mentioned. In such porous particles, the molar ratio MO _X / SiO ₂ when the silica is represented by SiO ₂ and the inorganic compound other than silica is represented by oxide (MO _x ) is 0.0001 to 1.0, Preferably it is in the range of 0.001 to 0.3. It is difficult to obtain a porous particle having a molar ratio MO _X / SiO ₂ of less than 0.0001. Even if it is obtained, particles having a small pore volume and a low refractive index cannot be obtained. In addition, when the molar ratio MO _X / SiO _{2 of} the porous particles exceeds 1.0, the ratio of silica decreases, so that the pore volume increases and it is difficult to obtain a material having a lower refractive index. is there.

  The pore volume of such porous particles is desirably in the range of 0.1 to 1.5 ml / g, preferably 0.2 to 1.5 ml / g. If the pore volume is less than 0.1 ml / g, particles having a sufficiently reduced refractive index cannot be obtained. If the pore volume exceeds 1.5 ml / g, the strength of the fine particles is lowered, and the strength of the resulting coating may be lowered. is there.

  Incidentally, the pore volume of such porous particles can be obtained by a mercury intrusion method. Examples of the contents of the hollow particles include a solvent, a gas, and a porous material used at the time of preparing the particles. The solvent may contain an unreacted particle precursor used in preparing the hollow particles, the catalyst used, and the like. Moreover, what consists of the compound illustrated by the said porous particle as a porous substance is mentioned. These contents may be composed of a single component or may be a mixture of a plurality of components.

  As a method for producing such inorganic fine particles, for example, the method for preparing composite oxide colloidal particles disclosed in paragraphs [0010] to [0033] of JP-A-7-133105 is suitably employed. Specifically, when the composite particles are composed of silica and an inorganic compound other than silica, the inorganic compound particles are produced from the following first to third steps.

First Step: Preparation of Porous Particle Precursor In the first step, an alkali aqueous solution of a silica raw material and an inorganic compound raw material other than silica is separately prepared in advance, or a silica raw material and an inorganic compound raw material other than silica are prepared in advance. A mixed aqueous solution is prepared, and this aqueous solution is gradually added to an aqueous alkaline solution having a pH of 10 or more while stirring according to the composite ratio of the target composite oxide to prepare a porous particle precursor.

  As the silica raw material, alkali metal, ammonium or organic base silicate is used. Sodium silicate (water glass) or potassium silicate is used as the alkali metal silicate. Examples of the organic base include quaternary ammonium salts such as tetraethylammonium salt, and amines such as monoethanolamine, diethanolamine, and triethanolamine. The ammonium silicate or the organic base silicate includes an alkaline solution obtained by adding ammonia, a quaternary ammonium hydroxide, an amine compound or the like to a silicic acid solution.

  In addition, alkali-soluble inorganic compounds are used as raw materials for inorganic compounds other than silica. Specifically, an oxo acid of an element selected from Al, B, Ti, Zr, Sn, Ce, P, Sb, Mo, Zn, W, etc., an alkali metal salt or alkaline earth metal salt of the oxo acid, ammonium Salts and quaternary ammonium salts. More specifically, sodium aluminate, sodium tetraborate, zirconyl ammonium carbonate, potassium antimonate, potassium stannate, sodium aluminosilicate, sodium molybdate, cerium ammonium nitrate, and sodium phosphate are suitable.

Although the pH value of the mixed aqueous solution changes simultaneously with the addition of these aqueous solutions, an operation for controlling the pH value within a predetermined range is not particularly required. The aqueous solution finally has a pH value determined by the type of inorganic oxide and the mixing ratio thereof. There is no restriction | limiting in particular in the addition rate of the aqueous solution at this time. Further, in the production of composite oxide particles, a dispersion of seed particles can be used as a starting material. The seed particles are not particularly limited, but inorganic oxides such as SiO ₂ , Al ₂ O ₃ , TiO ₂ or ZrO ₂ or fine particles of these composite oxides are used. Usually, these sols are used. I can do it. Furthermore, the porous particle precursor dispersion obtained by the above production method may be used as a seed particle dispersion. When the seed particle dispersion is used, the pH of the seed particle dispersion is adjusted to 10 or more, and then the aqueous solution of the compound is added to the above-described alkaline aqueous solution while stirring. Also in this case, it is not always necessary to control the pH of the dispersion. In this way, when seed particles are used, it is easy to control the particle size of the porous particles to be prepared, and particles having a uniform particle size can be obtained.

  The silica raw material and the inorganic compound raw material described above have high solubility on the alkali side. However, when both are mixed in this highly soluble pH region, the solubility of oxo acid ions such as silicate ions and aluminate ions decreases, and these composites precipitate and grow into fine particles, or seed particles. It grows on the top and particle growth occurs. Therefore, it is not always necessary to perform pH control as in the conventional method for precipitation and growth of fine particles.

The composite ratio of the silica and the inorganic compound other than silica in the first step is calculated by converting the inorganic compound to silica into an oxide (MO _X ), and the molar ratio of MO _X / SiO ₂ is 0.05 to 2.0, Preferably it is in the range of 0.2-2.0. Within this range, the pore volume of the porous particles increases as the proportion of silica decreases. However, even when the molar ratio exceeds 2.0, the pore volume of the porous particles hardly increases. On the other hand, when the molar ratio is less than 0.05, the pore volume becomes small. When preparing the hollow particles, the molar ratio of MO _X / SiO ₂ is desirably in the range of 0.25 to 2.0.

Second step: Removal of inorganic compound other than silica from porous particles In the second step, inorganic compounds other than silica (elements other than silicon and oxygen) are obtained from the porous particle precursor obtained in the first step. At least a portion is selectively removed. As a specific removal method, the inorganic compound in the porous particle precursor is dissolved and removed using a mineral acid or an organic acid, or is contacted with a cation exchange resin for ion exchange removal.

  The porous particle precursor obtained in the first step is a particle having a network structure in which silicon and an inorganic compound constituent element are bonded via oxygen. By removing the inorganic compound (elements other than silicon and oxygen) from the porous particle precursor in this way, porous particles having a larger porosity and a larger pore volume can be obtained. Further, if the amount of removing the inorganic oxide (elements other than silicon and oxygen) from the porous particle precursor is increased, the hollow particles can be prepared.

  In addition, prior to removing inorganic compounds other than silica from the porous particle precursor, a silicic acid solution obtained by removing the alkali metal salt of silica from the porous particle precursor dispersion obtained in the first step. Alternatively, it is preferable to form a silica protective film by adding a hydrolyzable organosilicon compound. The thickness of the silica protective film may be 0.5 to 15 nm. Even if the silica protective film is formed, the protective film in this step is porous and thin, so that it is possible to remove inorganic compounds other than silica described above from the porous particle precursor.

  By forming such a silica protective film, inorganic compounds other than the silica described above can be removed from the porous particle precursor while maintaining the particle shape. Further, when forming the silica coating layer described later, the pores of the porous particles are not blocked by the coating layer, and therefore the silica coating layer described later is formed without reducing the pore volume. I can do it. Note that when the amount of the inorganic compound to be removed is small, the particles are not broken, and thus it is not always necessary to form a protective film.

  When preparing hollow particles, it is desirable to form this silica protective film. When preparing the hollow particles, the inorganic compound is removed to obtain a hollow particle precursor composed of a silica protective film, a solvent in the silica protective film, and an undissolved porous solid content. When a coating layer to be described later is formed on the precursor, the formed coating layer becomes a particle wall to form hollow particles.

The amount of the silica source added for forming the silica protective film is preferably small as long as the particle shape can be maintained. If the amount of the silica source is too large, the silica protective film becomes too thick, and it may be difficult to remove inorganic compounds other than silica from the porous particle precursor. The hydrolyzable organic silicon compound used for the silica protective film formed of the general formula _{R n Si (OR ') 4} -n [R, R': an alkyl group, an aryl group, a vinyl group, such as acrylic group An alkoxysilane represented by a hydrocarbon group, n = 0, 1, 2, or 3] can be used. In particular, tetraalkoxysilanes such as tetramethoxysilane, tetraethoxysilane, and tetraisopropoxysilane are preferably used.

  As an addition method, a solution obtained by adding a small amount of alkali or acid as a catalyst to a mixed solution of these alkoxysilane, pure water, and alcohol is added to the dispersion of the porous particles, and the alkoxysilane is hydrolyzed. The produced silicic acid polymer is deposited on the surface of the inorganic oxide particles. At this time, alkoxysilane, alcohol, and catalyst may be simultaneously added to the dispersion. As the alkali catalyst, ammonia, an alkali metal hydroxide, or an amine can be used. As the acid catalyst, various inorganic acids and organic acids can be used.

  When the dispersion medium of the porous particle precursor is water alone or when the ratio of water to the organic solvent is high, a silica protective film can be formed using a silicic acid solution. When a silicic acid solution is used, a predetermined amount of the silicic acid solution is added to the dispersion, and at the same time an alkali is added to deposit the silicic acid solution on the surface of the porous particles. In addition, you may produce a silica protective film together using a silicic acid liquid and the said alkoxysilane.

Third Step: Formation of Silica Coating Layer In the third step, a hydrolyzable organosilicon compound or silicic acid solution is added to the porous particle dispersion prepared in the second step (in the case of hollow particles, a hollow particle precursor dispersion). Etc. is added to coat the surface of the particles with a polymer such as a hydrolyzable organosilicon compound or silicic acid solution to form a silica coating layer.

The hydrolyzable organic silicon compound used for the silica coating layer formed, the above-mentioned such general formula _{R n Si (OR ') 4} -n [R, R': an alkyl group, an aryl group, a vinyl group, A hydrocarbon group such as an acryl group or an alkoxysilane represented by n = 0, 1, 2, or 3] can be used. In particular, tetraalkoxysilanes such as tetramethoxysilane, tetraethoxysilane, and tetraisopropoxysilane are preferably used.

  As an addition method, a solution obtained by adding a small amount of alkali or acid as a catalyst to a mixed solution of these alkoxysilane, pure water, and alcohol is used as a dispersion of the porous particles (in the case of hollow particles, a hollow particle precursor). In addition, the silicic acid polymer produced by hydrolyzing alkoxysilane is deposited on the surface of the porous particles (in the case of hollow particles, hollow particle precursors). At this time, alkoxysilane, alcohol, and catalyst may be simultaneously added to the dispersion. As the alkali catalyst, ammonia, an alkali metal hydroxide, or an amine can be used. As the acid catalyst, various inorganic acids and organic acids can be used.

  When the dispersion medium of porous particles (in the case of hollow particles, the hollow particle precursor) is water alone or a mixed solvent with an organic solvent and the mixed solvent has a high ratio of water to the organic solvent, a silicate solution You may form a coating layer using. The silicic acid solution is an aqueous solution of a low silicic acid polymer obtained by dealkalizing an aqueous solution of an alkali metal silicate such as water glass by ion exchange treatment.

  The silicic acid solution is added to the dispersion of porous particles (in the case of hollow particles, hollow particle precursors), and at the same time, alkali is added to make the low-silicic acid polymer into porous particles (in the case of hollow particles, hollow particle precursors). ) Deposit on the surface. A silicic acid solution may be used in combination with the alkoxysilane for forming a coating layer. The addition amount of the organosilicon compound or silicic acid solution used for forming the coating layer only needs to be sufficient to cover the surface of the colloidal particles, and the finally obtained silica coating layer has a thickness of 1 to 20 nm. In such an amount, it is added in a dispersion of porous particles (in the case of hollow particles, hollow particle precursor) in a dispersion. When the silica protective film is formed, the organosilicon compound or the silicate solution is added in such an amount that the total thickness of the silica protective film and the silica coating layer is in the range of 1 to 20 nm.

  Next, the dispersion liquid of the particles on which the coating layer is formed is heat-treated. By the heat treatment, in the case of porous particles, the silica coating layer covering the surface of the porous particles is densified, and a dispersion of composite particles in which the porous particles are coated with the silica coating layer is obtained. In the case of a hollow particle precursor, the formed coating layer is densified to form hollow particle walls, and a dispersion of hollow particles having cavities filled with a solvent, gas, or porous solid content is obtained.

  The heat treatment temperature at this time is not particularly limited as long as it can close the fine pores of the silica coating layer, and is preferably in the range of 80 to 300 ° C. When the heat treatment temperature is less than 80 ° C., the fine pores of the silica coating layer may not be completely closed and densified, and the treatment time may take a long time. Further, when the heat treatment temperature exceeds 300 ° C. for a long time, fine particles may be formed, and the effect of low refractive index may not be obtained.

  The refractive index of the inorganic fine particles thus obtained is as low as less than 1.42. Such inorganic fine particles are presumed to have a low refractive index because the porosity inside the porous particles is maintained or the inside is hollow.

  Next, (B) the binder component will be described.

  As the binder matrix of the low refractive index layer, a fluorine-containing resin that is crosslinked by heat or ionizing radiation (hereinafter also referred to as “fluorine-containing resin before crosslinking”) is preferably used.

  Preferred examples of the fluorine-containing resin before crosslinking include a fluorine-containing copolymer formed from a fluorine-containing vinyl monomer and a monomer for imparting a crosslinkable group. Specific examples of the fluorine-containing vinyl monomer unit include, for example, fluoroolefins (for example, fluoroethylene, vinylidene fluoride, tetrafluoroethylene, hexafluoroethylene, hexafluoropropylene, perfluoro-2,2-dimethyl-1,3 -Dioxoles, etc.), (meth) acrylic acid partial or fully fluorinated alkyl ester derivatives (for example, Biscoat 6FM (produced by Osaka Organic Chemicals) or M-2020 (produced by Daikin)), fully or partially fluorinated vinyl ethers, etc. Is mentioned.

  As monomers for imparting a crosslinkable group, glycidyl methacrylate, vinyltrimethoxysilane, γ-methacryloyloxypropyltrimethoxysilane, vinyl glycidyl ether, and other vinyl monomers having a crosslinkable functional group in advance in the molecule. , Vinyl monomers having a carboxyl group, hydroxyl group, amino group, sulfonic acid group, etc. (for example, (meth) acrylic acid, methylol (meth) acrylate, hydroxyalkyl (meth) acrylate, allyl acrylate, hydroxyalkyl vinyl ether, hydroxyalkyl allyl) Ether, etc.). The latter can introduce a cross-linked structure by adding a compound having a group that reacts with a functional group in the polymer and another reactive group after copolymerization. No. 147739. Examples of the crosslinkable group include acryloyl, methacryloyl, isocyanate, epoxy, aziridine, oxazoline, aldehyde, carbonyl, hydrazine, carboxyl, methylol, and active methylene group. When the fluorine-containing copolymer is cross-linked by heating by a cross-linking group that reacts by heating, or a combination of an ethylenically unsaturated group and a thermal radical generator or an epoxy group and a thermal acid generator, the thermosetting type In the case of crosslinking by irradiation with light (preferably ultraviolet rays, electron beams, etc.) by a combination of an ethylenically unsaturated group and a photo radical generator, or an epoxy group and a photo acid generator, etc., it is an ionizing radiation curable type .

  Further, in addition to the above monomers, a fluorine-containing copolymer formed by using a monomer other than the fluorine-containing vinyl monomer and the monomer for imparting a crosslinkable group may be used as the fluorine-containing resin before crosslinking. The monomer that can be used in combination is not particularly limited. For example, olefins (ethylene, propylene, isoprene, vinyl chloride, vinylidene chloride, etc.), acrylic esters (methyl acrylate, methyl acrylate, ethyl acrylate, 2-acrylic acid 2- Ethyl hexyl), methacrylates (methyl methacrylate, ethyl methacrylate, butyl methacrylate, ethylene glycol dimethacrylate, etc.), styrene derivatives (styrene, divinylbenzene, vinyl toluene, α-methylstyrene, etc.), vinyl ethers (methyl vinyl ether) Etc.), vinyl esters (vinyl acetate, vinyl propionate, vinyl cinnamate, etc.), acrylamides (N-tertbutylacrylamide, N-cyclohexylacrylamide, etc.), methacrylamides, Ronitoriru derivatives and the like can be mentioned. In addition, it is also preferable to introduce a polyorganosiloxane skeleton or a perfluoropolyether skeleton into the fluorinated copolymer in order to impart slipperiness and antifouling properties. For example, polyorganosiloxane or perfluoropolyether having an acrylic group, methacrylic group, vinyl ether group, styryl group or the like at the terminal is polymerized with the above monomer, and polyorganosiloxane or perfluoropolyester having a radical generating group at the terminal. It can be obtained by polymerization of the above monomers with ether, reaction of a polyorganosiloxane or perfluoropolyether having a functional group with a fluorine-containing copolymer, or the like.

  The proportion of each of the above monomers used to form the fluorinated copolymer before crosslinking is preferably 20 to 70 mol%, more preferably 40 to 70 mol%, more preferably 40 to 70 mol% of the fluorinated vinyl monomer. The amount of the monomer is preferably 1 to 20 mol%, more preferably 5 to 20 mol%, and the other monomer used in combination is preferably 10 to 70 mol%, more preferably 10 to 50 mol%.

  The fluorine-containing copolymer can be obtained by polymerizing these monomers in the presence of a radical polymerization initiator by means such as solution polymerization, bulk polymerization, emulsion polymerization, suspension polymerization.

  The fluorine-containing resin before crosslinking is commercially available and can be used. Examples of commercially available fluorine-containing resins before cross-linking include Cytop (Asahi Glass), Teflon (R) AF (DuPont), polyvinylidene fluoride, Lumiflon (Asahi Glass), OPSTAR (JSR), etc. Can be mentioned.

  The low refractive index layer containing a cross-linked fluororesin as a constituent component preferably has a dynamic friction coefficient in the range of 0.03 to 0.15 and a contact angle with water in the range of 90 to 120 degrees.

  Various sol-gel materials can also be used as a binder matrix for other low refractive index layers. As such a sol-gel material, metal alcoholates (alcohols such as silane, titanium, aluminum, and zirconium), organoalkoxy metal compounds, and hydrolysates thereof can be used. In particular, alkoxysilane, organoalkoxysilane and its hydrolysis polycondensate are preferable. Examples of these include tetraalkoxysilane (tetramethoxysilane, tetraethoxysilane, etc.), alkyltrialkoxysilane (methyltrimethoxysilane, ethyltrimethoxysilane, etc.), aryltrialkoxysilane (phenyltrimethoxysilane, etc.), dialkyl. Examples thereof include dialkoxysilane and diaryl dialkoxysilane. In addition, organoalkoxysilanes having various functional groups (vinyl trialkoxysilane, methylvinyl dialkoxysilane, γ-glycidyloxypropyltrialkoxysilane, γ-glycidyloxypropylmethyl dialkoxysilane, β- (3,4-epoxy) Dicyclohexyl) ethyltrialkoxysilane, γ-methacryloyloxypropyltrialkoxysilane, γ-aminopropyltrialkoxysilane, γ-mercaptopropyltrialkoxysilane, γ-chloropropyltrialkoxysilane, etc.), perfluoroalkyl group-containing silane compounds ( For example, (heptadecafluoro-1,1,2,2-tetradecyl) triethoxysilane, 3,3,3-trifluoropropyltrimethoxysilane, etc.), containing fluoroalkyl ether group It is also preferable to use a run-compound. Use of a fluorine-containing silane compound is preferable in terms of lowering the refractive index of the layer and imparting water and oil repellency.

  Of the above, hydrolysis polycondensates of alkoxysilane compounds are particularly preferred, and among the alkoxysilane compounds, tetraethoxysilane is more preferred, and among the alkoxysilane compounds used, 50% or more is most preferably tetraethoxysilane.

  The low refractive index layer preferably contains a binder component in an amount of 5 to 50% by mass. The binder has a function of adhering fine particles and maintaining the structure of the low refractive index layer including voids. The usage-amount of a binder is adjusted so that the intensity | strength of a low refractive index layer can be maintained, without filling a space | gap. The amount of the polymer serving as the binder is preferably 10 to 30% by mass of the total amount of the low refractive index layer. In order to adhere the fine particles with the polymer, it is also preferable to bond the polymer to a surface treatment agent for fine particles as shown in (1) below, or (2) to form a polymer shell around the fine particles as a core. The shell polymer (2) is preferably formed around the fine particles by a polymerization reaction before preparing the coating solution for the low refractive index layer. The binder component represented by (B) may be formed by adding a monomer to the coating solution for the low refractive index layer and performing a polymerization reaction simultaneously with or after coating the low refractive index layer. (1) Surface treatment and (2) Shell will be described sequentially.

(1) Surface treatment It is preferable to improve the affinity with the polymer by subjecting the composite particles or hollow particles according to the present invention to a surface treatment. The surface treatment can be classified into physical surface treatment such as plasma discharge treatment and corona discharge treatment, and chemical surface treatment using a coupling agent. It is preferable to carry out only chemical surface treatment or a combination of physical surface treatment and chemical surface treatment. As the coupling agent, an organoalkoxy metal compound (eg, titanium coupling agent, silane coupling agent) is preferably used. Particles when made of SiO _2, surface treatment with a silane coupling agent can be particularly effectively conducted. As a specific example of the silane coupling agent, a silane coupling agent described later is preferably used.

  The surface treatment with the coupling agent can be carried out by adding the coupling agent to the fine particle dispersion and allowing the dispersion to stand at a temperature from room temperature to 60 ° C. for several hours to 10 days. In order to accelerate the surface treatment reaction, inorganic acids (for example, sulfuric acid, hydrochloric acid, nitric acid, chromic acid, hypochlorous acid, boric acid, orthosilicic acid, phosphoric acid, carbonic acid), organic acids (for example, acetic acid, polyacrylic acid, Benzenesulfonic acid, phenol, polyglutamic acid), or salts thereof (eg, metal salts, ammonium salts) may be added to the dispersion.

(2) Shell The polymer that forms a shell for the composite particles or the hollow particles according to the present invention is preferably a polymer having a saturated hydrocarbon as a main chain. A polymer containing a fluorine atom in the main chain or side chain is preferred, and a polymer containing a fluorine atom in the side chain is more preferred. Polyacrylic acid esters or polymethacrylic acid esters are preferred, and esters of fluorine-substituted alcohols with polyacrylic acid or polymethacrylic acid are most preferred. The refractive index of the shell polymer decreases as the content of fluorine atoms in the polymer increases. In order to lower the refractive index of the low refractive index layer, the shell polymer preferably contains 35 to 80% by mass of fluorine atoms, and more preferably contains 45 to 75% by mass of fluorine atoms. The polymer containing a fluorine atom is preferably synthesized by a polymerization reaction of an ethylenically unsaturated monomer containing a fluorine atom. Examples of ethylenically unsaturated monomers containing fluorine atoms include fluoroolefins (eg, fluoroethylene, vinylidene fluoride, tetrafluoroethylene, hexafluoropropylene, perfluoro-2,2-dimethyl-1,3-dioxole), Mention may be made of esters of fluorinated vinyl ethers and fluorine-substituted alcohols with acrylic acid or methacrylic acid.

  The polymer forming the shell may be a copolymer composed of a repeating unit containing a fluorine atom and a repeating unit not containing a fluorine atom. The repeating unit containing no fluorine atom is preferably obtained by a polymerization reaction of an ethylenically unsaturated monomer containing no fluorine atom. Examples of ethylenically unsaturated monomers that do not contain fluorine atoms include olefins (eg, ethylene, propylene, isoprene, vinyl chloride, vinylidene chloride), acrylic acid esters (eg, methyl acrylate, ethyl acrylate, acrylic acid 2- Ethyl hexyl), methacrylic acid esters (for example, methyl methacrylate, ethyl methacrylate, butyl methacrylate, ethylene glycol dimethacrylate), styrene and its derivatives (for example, styrene, divinylbenzene, vinyltoluene, α-methylstyrene), vinyl ether ( For example, methyl vinyl ether), vinyl esters (for example, vinyl acetate, vinyl propionate, vinyl cinnamate), acrylamide (for example, N-tertbutylacrylamide, N-cyclohexylacrylic) Amides), methacrylamide and acrylonitrile.

  When the binder component (B) is used, a crosslinkable functional group may be introduced into the shell polymer to chemically bond the shell polymer and the polymer constituting the binder component by crosslinking. The shell polymer may have crystallinity. When the glass transition temperature (Tg) of the shell polymer is higher than the temperature at the time of forming the low refractive index layer, it is easy to maintain microvoids in the low refractive index layer. However, if Tg is higher than the temperature at which the low refractive index layer is formed, the fine particles are not fused, and the low refractive index layer may not be formed as a continuous layer (resulting in a decrease in strength). In that case, it is desirable to use together the polymer used as the binder component represented by (B), and form the low refractive index layer as a continuous layer with the binder polymer. By forming a polymer shell around the fine particles, core-shell fine particles are obtained. The core-shell fine particles preferably contain 5 to 90% by volume of a core composed of inorganic fine particles, and more preferably 15 to 80% by volume. Two or more kinds of core-shell fine particles may be used in combination. Further, inorganic fine particles having no shell and core-shell particles may be used in combination.

  The polymer serving as the binder component is preferably formed by adding a monomer to the coating solution for the low refractive index layer, and at the same time as or after coating the low refractive index layer, by a polymerization reaction (further, if necessary). Even if a small amount of polymer (for example, polyvinyl alcohol, polyoxyethylene, polymethyl methacrylate, polymethyl acrylate, diacetyl cellulose, triacetyl cellulose, nitrocellulose, polyester, alkyd resin) is added to the coating solution for the low refractive index layer Good.

  Next, the nonionic surfactant in which the hydrophobic group represented by (C) is composed of dimethylpolysiloxane and the hydrophilic group is composed of polyoxyalkylene will be described.

  A nonionic surfactant is a generic term for a system surfactant that does not have a group capable of dissociating into ions in an aqueous solution. In addition to a hydrophobic group, a hydrophilic group includes a hydroxyl group of a polyhydric alcohol, a polyoxyalkylene chain ( Polyoxyethylene) or the like as a hydrophilic group. The hydrophilicity becomes stronger as the number of alcoholic hydroxyl groups increases and as the polyoxyalkylene chain (polyoxyethylene chain) becomes longer. The nonionic surfactant according to the present invention is characterized by having dimethylpolysiloxane as a hydrophobic group.

When a nonionic surfactant composed of a dimethylpolysiloxane having a hydrophobic group and a polyoxyalkylene having a hydrophilic group is used, the unevenness of the low refractive index layer and the antifouling property of the film surface are improved. It is thought that the hydrophobic group made of polymethylsiloxane is oriented on the surface and forms a film surface that is not easily soiled. This effect cannot be obtained by using other surfactants.
Specific examples of these nonionic surfactants include, for example, Nippon Unicar Co., Ltd., silicone surfactants SILWET L-77, L-720, L-7001, L-7002, L-7604, Y-7006, FZ-2101, FZ-2104, FZ-2105, FZ-2110, FZ-2118, FZ-2120, FZ-2122, FZ-2123, FZ-2130, FZ-2154, FZ-2161, FZ-2162, FZ- 2163, FZ-2164, FZ-2166, FZ-2191 and the like.

Also, SUPERSILWET SS-2801, SS-2802, SS-2803, SS-2804, SS-2805
In addition, as a preferable structure of the nonionic surfactant in which the hydrophobic group is composed of dimethylpolysiloxane and the hydrophilic group is composed of polyoxyalkylene, a dimethylpolysiloxane structure portion and a polyoxyalkylene chain are alternately and repeatedly bonded. It is preferably a linear block copolymer. Since the main chain skeleton has a long chain length and a linear structure, it is excellent. This is considered to be due to the fact that one activator molecule can be adsorbed on the surface of the silica fine particle at a plurality of locations so as to cover the surface of the silica fine particle by being a block copolymer in which hydrophilic groups and hydrophobic groups are alternately repeated.

  Specific examples thereof include, for example, silicone surfactants ABN SILWET FZ-2203, FZ-2207, FZ-2208 and the like manufactured by Nippon Unicar Co., Ltd.

  Using other anionic, cationic or other nonionic surfactants, composite particles having the porous particles and a coating layer provided on the surface of the porous particles, or a solvent, gas or porous inside Dispersion of hollow particles filled with a substance, which tends to occur when forming a low refractive index layer, coating unevenness is not just unevenness, but also greatly affects antifouling properties, reflection performance, etc. By using these nonionic surfactants according to the present invention, these unevennesses are substantially eliminated.

  However, other surfactants may be used in combination, and as appropriate, for example, anionic surfactants such as sulfonates, sulfates, phosphates, etc., and polyoxyethylene chain hydrophilic groups A nonionic surfactant such as an ether type or an ether ester type may be used in combination, or a fluorine-containing surfactant may be used.

  The low refractive index layer according to the present invention can be formed on the surface of a substrate such as glass, polycarbonate, acrylic resin, a plastic sheet such as PET or TAC, or a plastic film. Depending on the application, the low-refractive-index layer coating is formed on these substrates, either alone or as a protective film, hard coat film, high-refractive index film, insulating film, conductive resin film, conductive metal fine particle film, conductive metal. It is formed in combination with an oxide fine particle film, a primer film used if necessary, and the like. Such a low refractive index layer coating is applied to a base material by a known method such as a dipping method, a spray method, a spinner method, a roll coating method, etc., dried, and further fired as necessary. Can be obtained.

  The coating solution is a composite particle having the above-described (A) porous particles and a coating layer provided on the surface of the porous particles, or a hollow particle dispersion (inside, filled with a solvent, gas, or porous substance) Sol) and (B) binder component for film formation, and (C) a nonionic surfactant composed of dimethylpolysiloxane with hydrophobic group and polyoxyalkylene with hydrophilic group, and if necessary An organic solvent may be mixed. The film-forming binder component (matrix) refers to a component capable of forming a film on the surface of the base material, the fluorine-containing resin that is crosslinked by the heat or ionizing radiation, or alkoxysilane and its hydrolysis polycondensate, Among them, a sol-gel material such as tetraethoxysilane is preferable.

  A composite particle having a porous particle according to the present invention and a coating layer provided on the surface of the porous particle, or a dispersion sol of hollow particles filled with a solvent, a gas, or a porous substance therein, and water as a dispersion medium After treating the composite particles or hollow particles with a known coupling agent as necessary, the binder resin is diluted with a suitable organic solvent as a matrix. In addition, the nonionic surfactant can be added to form a coating solution.

  On the other hand, when using a hydrolyzable organosilicon compound such as alkoxysilane as the binder resin (matrix), for example, by adding water or an acid or alkali as a catalyst to a mixture of alkoxysilane and alcohol, the alkoxysilane Of the above-mentioned porous particles and composite particles having a coating layer provided on the surface of the porous particles, or hollow particles filled with a solvent, gas, or porous substance inside The dispersion sol and the nonionic surfactant can be mixed and diluted with an organic solvent as necessary to obtain a coating solution.

  The nonionic surfactant (C) in which the hydrophobic group is composed of dimethylpolysiloxane and the hydrophilic group is composed of polyalkylene oxide may be added in any process of the mixing. By adding these surfactants, a stable dispersion is formed in the silica-based fine particles / matrix, so that there is no unevenness due to partial aggregation and the like, and a uniform film can be formed. These effects cannot be obtained with other surfactants. In these silica-based fine particles / matrix, the amount of the surfactant represented by (C) is preferably 0.001 to 5 parts by mass with respect to the low refractive index coating composition (solid content). A particularly preferable blending ratio is 0.003 to 3 parts by mass.

  The mass ratio of the silica-based fine particles and the matrix in the coating solution is preferably in the range of silica-based fine particles / matrix = 1/99 to 9/1. If the mass ratio exceeds 9/1, the strength of the coating is insufficient and lacks practicality, while if it is less than 1/99, the effect of adding the silica-based fine particles does not appear. The refractive index of the coating film formed on the surface of the base material varies depending on the mixing ratio of the silica-based fine particles and the binder component (matrix component) and the refractive index of the matrix used. . The refractive index is 20 to 1.42. The refractive index of the silica-based fine particles themselves of the present invention was 1.20 to 1.38. This is because even when the dispersion medium enters the cavity, the dispersion medium is detached and becomes voids when the coating is dried, and the outer shell has micropores and the thickness of the outer shell is controlled within the above range. This is because the film-forming component such as resin stays in the outer shell, and after the resin is cured, the pores of the outer shell are blocked and the cavities inside the silica-based fine particles are retained.

  Furthermore, when the refractive index of the base material forming the antireflection layer is 1.60 or less, a film having a refractive index of 1.60 or more (hereinafter referred to as an intermediate film) is formed on the surface of the base material. It is recommended to form a film containing the silica-based fine particles of the present invention. If the refractive index of the intermediate coating is 1.60 or more, a coated substrate having a large difference from the refractive index of the coating containing silica-based fine particles of the present invention and excellent antireflection performance can be obtained. The refractive index of the intermediate coating can be adjusted by the type of metal oxide fine particles used, the mixing ratio of metal oxide and resin, and the refractive index of the resin used. The coating solution for forming an intermediate coating is a mixed solution of metal oxide particles and a matrix for forming a coating, and an organic solvent is mixed as necessary. As the film forming matrix, the same film as that containing the silica-based fine particles of the present invention can be used. By using the same film forming matrix, the coated substrate having excellent adhesion between the two films Is obtained.

  The substrate (film) on which the low reflective layer according to the present invention is coated will be described.

  As the base material, glass, polycarbonate, acrylic resin, cellulose ester, among them, plastic films such as triacetyl cellulose (TAC) and polyethylene terephthalate (PET), base materials such as plastic lenses and plastic panels, cathode ray tubes, Various substrates such as fluorescent display tubes and liquid crystal display panels can be used, and an antireflection layer can be formed on the surface of the substrate. However, since the birefringence wavelength dispersion characteristic is positive, for example, visible Polarization compensation is possible in the entire wavelength region of light, and there is no color shift in a liquid crystal panel adopting a display method using birefringence, and a good contrast in an organic EL display element, etc. Because of its excellent optical properties, when it is necessary to construct an antireflection film for use in these elements, Scan ester film is mainly used preferably.

  Therefore, the antireflection film according to the present invention has cellulose ester as a base material, and the low refractive index layer has a refractive index of 1 on an actinic ray curable resin layer (hard coat layer) provided on the base material. It is preferable that a low refractive index layer of 20 to 1.42 be provided directly or indirectly to form an antireflection layer by optical interference to form an antireflection film.

  Hereinafter, the cellulose ester film used for this invention and the antireflection film which used this as a base material are explained in full detail.

<Cellulose ester>
The molecular weight of the cellulose ester used in the present invention is 80,000 to 200,000 in number average molecular weight (Mn). 100,000 to 200,000 are more preferable, and 150,000 to 200,000 are particularly preferable.

  The cellulose ester used in the present invention has a weight average molecular weight (Mw) to number average molecular weight (Mn) ratio, Mw / Mn of 1.4 to 3.0 as described above, but preferably 1.7. It is the range of -2.2.

  The average molecular weight and molecular weight distribution of the cellulose ester can be measured by a known method using high performance liquid chromatography. Using this, the number average molecular weight and the weight average molecular weight can be calculated, and the ratio (Mw / Mn) can be calculated.

The measurement conditions are as follows.
Solvent: Methylene chloride column: Shodex K806, K805, K803G (used by connecting 3 products manufactured by Showa Denko KK)
Column temperature: 25 ° C
Sample concentration: 0.1% by mass
Detector: RI Model 504 (manufactured by GL Sciences)
Pump: L6000 (manufactured by Hitachi, Ltd.)
Flow rate: 1.0ml / min
Calibration curve: Standard polystyrene STK standard polystyrene (manufactured by Tosoh Corp.) Mw = 100000-500 calibration curves with 13 samples were used. It is preferable to obtain 13 samples at approximately equal intervals.

  The cellulose ester used in the present invention is a carboxylic acid ester having about 2 to 22 carbon atoms, and is particularly preferably a lower fatty acid ester of cellulose. The lower fatty acid in the lower fatty acid ester of cellulose means a fatty acid having 6 or less carbon atoms. For example, cellulose acetate, cellulose propionate, cellulose butyrate, cellulose acetate phthalate, etc., JP-A-10-45804, Mixed fatty acid esters such as cellulose acetate propionate and cellulose acetate butyrate as described in U.S. Pat. No. 8,231,761, U.S. Pat. No. 2,319,052 can be used. Among the above descriptions, the lower fatty acid esters of cellulose particularly preferably used are cellulose triacetate and cellulose acetate propionate. These cellulose esters can be used as a mixture.

  In the case of cellulose triacetate, those having a total acyl group substitution degree (acetyl group substitution degree) of 2.6 to 2.9 are preferably used.

  Preferred cellulose esters other than cellulose triacetate have an acyl group having 2 to 4 carbon atoms as a substituent, the substitution degree of acetyl group is X, and the substitution degree of propionyl group is Y, the following formula (I) And (II) at the same time.

Formula (I) 2.6 ≦ X + Y ≦ 2.9
Formula (II) 0 ≦ X ≦ 2.5
Among them, cellulose acetate propionate (total acyl group substitution degree = X + Y) satisfying 1.9 ≦ X ≦ 2.5 and 0.1 ≦ Y ≦ 0.9 is preferable. The portion not substituted with an acyl group usually exists as a hydroxyl group. These can be synthesized by known methods.

  These acyl group substitution degrees can be measured according to the method prescribed in ASTM-D817-96.

  As the cellulose ester, a cellulose ester synthesized using cotton linter, wood pulp, kenaf or the like as a raw material can be used alone or in combination. In particular, it is preferable to use a cotton linter (hereinafter sometimes simply referred to as a linter) or a cellulose ester synthesized from wood pulp alone or in combination.

  Moreover, the cellulose ester obtained from these can be mixed and used in arbitrary ratios, respectively. These cellulose esters are prepared by using an organic acid such as acetic acid or an organic solvent such as methylene chloride when sulfuric acid is used as the acylating agent (acetic anhydride, propionic anhydride, butyric anhydride). It can obtain by making it react by a conventional method using a protic catalyst like.

  In the case of acetyl cellulose, it is necessary to extend the time for the acetylation reaction in order to increase the acetylation rate. However, if the reaction time is too long, the decomposition proceeds at the same time, and the polymer chain is broken or the acetyl group is decomposed, resulting in an undesirable result. Therefore, it is necessary to set the reaction time within a certain range in order to increase the degree of acetylation and suppress decomposition to some extent. It is not appropriate to define the reaction time because the reaction conditions are various and greatly change depending on the reaction apparatus, equipment and other conditions. As the decomposition of the polymer progresses, the molecular weight distribution becomes wider. Therefore, in the case of cellulose ester, the degree of decomposition can be defined by the value of weight average molecular weight (Mw) / number average molecular weight (Mn) that is usually used. In other words, in the process of acetylation of cellulose triacetate, the weight average molecular weight is used as one index of the reaction level for allowing the acetylation reaction to take place for a sufficient time for acetylation without being too long and being decomposed too much. The value of (Mw) / number average molecular weight (Mn) can be used.

  An example of a method for producing a cellulose ester is shown below: 100 parts by mass of a flocculent linter was crushed as a cellulose raw material, 40 parts by mass of acetic acid was added, and pretreatment activation was performed at 36 ° C. for 20 minutes. Thereafter, 8 parts by mass of sulfuric acid, 260 parts by mass of acetic anhydride and 350 parts by mass of acetic acid were added, and esterification was performed at 36 ° C. for 120 minutes. After neutralization with 11 parts by mass of a 24% magnesium acetate aqueous solution, saponification aging was carried out at 63 ° C. for 35 minutes to obtain acetylcellulose. This was stirred for 160 minutes at room temperature using a 10-fold acetic acid aqueous solution (acetic acid: water = 1: 1 (mass ratio)), then filtered and dried to obtain purified acetylcellulose having an acetyl substitution degree of 2.75. . This acetylcellulose had Mn of 92,000, Mw of 156,000, and Mw / Mn of 1.7. Similarly, cellulose esters having different degrees of substitution and Mw / Mn ratios can be synthesized by adjusting the esterification conditions (temperature, time, stirring) and hydrolysis conditions of the cellulose ester.

  In the case of a mixed acid cellulose ester, it can be obtained by a reaction described in JP-A-10-45804. The measuring method of the substitution degree of an acyl group can be measured according to the rule of ASTM-D817-96.

  Cellulose esters are also affected by trace metal components in cellulose esters. These are considered to be related to water used in the production process, but it is preferable that there are few components that can become insoluble nuclei, and metal ions such as iron, calcium, and magnesium contain organic acidic groups. Insoluble matter may be formed by salt formation with a polymer degradation product or the like that may be present, and it is preferable that the amount is small. The iron (Fe) component is preferably 1 ppm or less. About calcium (Ca) component, it is contained in a lot of ground water and river water, etc., and it becomes hard water, and it is unsuitable as drinking water. Ligand and coordination compounds, that is, complexes are easily formed, and many unnecessary calcium-derived scum (insoluble starch, turbidity) is formed.

  The calcium (Ca) component is 60 ppm or less, preferably 0 to 30 ppm. The magnesium (Mg) component is preferably in the range of 0 to 70 ppm, and more preferably 0 to 20 ppm, because too much will cause insoluble matter. Metal components such as iron (Fe) content, calcium (Ca) content, magnesium (Mg) content, etc. are pre-processed by completely digesting cellulose ester with micro digest wet cracking equipment (sulfuric acid decomposition) and alkali melting. After performing, it can obtain | require by performing an analysis using ICP-AES (inductively coupled plasma optical emission spectrometry).

<Plasticizer>
The cellulose ester film used in the present invention contains at least two kinds of plasticizers. Further, it does not substantially contain a phosphate ester plasticizer such as triphenyl phosphate. “Substantially not containing” means that the content of the phosphoric ester plasticizer is less than 1% by mass, preferably 0.1% by mass, particularly preferably not added.

  By including two or more plasticizers, elution of the plasticizer can be reduced. The reason is not clear, but it seems that elution is suppressed by the ability to reduce the amount added per type and the interaction between the two plasticizers and the cellulose ester.

  The two plasticizers are not particularly limited, but are preferably selected from the polyhydric alcohol ester plasticizer, phthalic acid ester, citrate ester, fatty acid ester, glycolate plasticizer, polyvalent carboxylic acid ester, and the like. . Of these, at least one is preferably a polyhydric alcohol ester plasticizer.

  The polyhydric alcohol ester plasticizer is a plasticizer comprising an ester of a dihydric or higher aliphatic polyhydric alcohol and a monocarboxylic acid, and preferably has an aromatic ring or a cycloalkyl ring in the molecule. Preferably it is a 2-20 valent aliphatic polyhydric alcohol ester.

  The polyhydric alcohol used in the present invention is represented by the following general formula (1).

Formula (1) R _1- (OH) n
However, R ₁ represents an n-valent organic group, n represents a positive integer of 2 or more, and the OH group represents an alcoholic and / or phenolic hydroxyl group.

  Examples of preferred polyhydric alcohols include the following, but the present invention is not limited to these. Adonitol, arabitol, ethylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, 1,2-propanediol, 1,3-propanediol, dipropylene glycol, tripropylene glycol, 1,2-butanediol, 1,3- Butanediol, 1,4-butanediol, dibutylene glycol, 1,2,4-butanetriol, 1,5-pentanediol, 1,6-hexanediol, hexanetriol, galactitol, mannitol, 3-methylpentane- Examples include 1,3,5-triol, pinacol, sorbitol, trimethylolpropane, trimethylolethane, and xylitol. In particular, triethylene glycol, tetraethylene glycol, dipropylene glycol, tripropylene glycol, sorbitol, trimethylolpropane, and xylitol are preferable.

  There is no restriction | limiting in particular as monocarboxylic acid used for the polyhydric alcohol ester of this invention, Well-known aliphatic monocarboxylic acid, alicyclic monocarboxylic acid, aromatic monocarboxylic acid, etc. can be used. Use of an alicyclic monocarboxylic acid or aromatic monocarboxylic acid is preferred in terms of improving moisture permeability and retention.

  Examples of preferred monocarboxylic acids include the following, but the present invention is not limited thereto.

  As the aliphatic monocarboxylic acid, a fatty acid having a straight chain or a side chain having 1 to 32 carbon atoms can be preferably used. The number of carbon atoms is more preferably 1-20, and particularly preferably 1-10. When acetic acid is contained, the compatibility with the cellulose ester is increased, and it is also preferable to use a mixture of acetic acid and another monocarboxylic acid.

  Preferred aliphatic monocarboxylic acids include acetic acid, propionic acid, butyric acid, valeric acid, caproic acid, enanthic acid, caprylic acid, pelargonic acid, capric acid, 2-ethyl-hexanoic acid, undecylic acid, lauric acid, tridecylic acid, Saturated fatty acids such as myristic acid, pentadecylic acid, palmitic acid, heptadecylic acid, stearic acid, nonadecanoic acid, arachidic acid, behenic acid, lignoceric acid, serotic acid, heptacosanoic acid, montanic acid, melicic acid, laccelic acid, undecylenic acid, olein Examples thereof include unsaturated fatty acids such as acid, sorbic acid, linoleic acid, linolenic acid, and arachidonic acid.

  Examples of preferable alicyclic monocarboxylic acids include cyclopentanecarboxylic acid, cyclohexanecarboxylic acid, cyclooctanecarboxylic acid, and derivatives thereof.

  Examples of preferred aromatic monocarboxylic acids include those in which an alkyl group is introduced into the benzene ring of benzoic acid such as benzoic acid and toluic acid, and two or more benzene rings such as biphenylcarboxylic acid, naphthalenecarboxylic acid, and tetralincarboxylic acid. The aromatic monocarboxylic acid which has, or those derivatives can be mentioned. Benzoic acid is particularly preferable.

  The molecular weight of the polyhydric alcohol ester is not particularly limited, but is preferably 300 to 1500, and more preferably 350 to 750. A higher molecular weight is preferred because it is less likely to volatilize, and a smaller one is preferred in terms of moisture permeability and compatibility with cellulose ester.

  The carboxylic acid used for the polyhydric alcohol ester may be one kind or a mixture of two or more kinds. Moreover, all the OH groups in the polyhydric alcohol may be esterified, or a part of the OH groups may be left as they are.

  Below, the specific compound of a polyhydric alcohol ester is illustrated.

  The glycolate plasticizer is not particularly limited, but alkylphthalylalkyl glycolates can be preferably used. Examples of alkyl phthalyl alkyl glycolates include methyl phthalyl methyl glycolate, ethyl phthalyl ethyl glycolate, propyl phthalyl propyl glycolate, butyl phthalyl butyl glycolate, octyl phthalyl octyl glycolate, methyl phthalyl ethyl Glycolate, ethyl phthalyl methyl glycolate, ethyl phthalyl propyl glycolate, methyl phthalyl butyl glycolate, ethyl phthalyl butyl glycolate, butyl phthalyl methyl glycolate, butyl phthalyl ethyl glycolate, propyl phthalyl butyl glycol Butyl phthalyl propyl glycolate, methyl phthalyl octyl glycolate, ethyl phthalyl octyl glycolate, octyl phthalyl methyl glycolate, octyl phthalate Ethyl glycolate, and the like.

  Examples of the phthalate ester plasticizer include diethyl phthalate, dimethoxyethyl phthalate, dimethyl phthalate, dioctyl phthalate, dibutyl phthalate, di-2-ethylhexyl phthalate, dioctyl phthalate, dicyclohexyl phthalate, and dicyclohexyl terephthalate.

  Examples of the citrate plasticizer include acetyl trimethyl citrate, acetyl triethyl citrate, and acetyl tributyl citrate.

  Examples of fatty acid ester plasticizers include butyl oleate, methylacetyl ricinoleate, and dibutyl sebacate.

  Polycarboxylic acid ester plasticizers can also be preferably used. Specifically, it is preferable to add the polyvalent carboxylic acid ester described in paragraphs [0015] to [0020] of JP-A No. 2002-265639 as one of the plasticizers.

  Examples of the phosphate ester plasticizer include triphenyl phosphate, tricresyl phosphate, cresyl diphenyl phosphate, octyl diphenyl phosphate, diphenyl biphenyl phosphate, trioctyl phosphate, tributyl phosphate, and the like. The agent is not substantially contained in the cellulose ester film constituting the present invention. As described above, “not containing substantially” means that the content is less than 1% by mass, preferably less than 0.1% by mass, and particularly preferably not contained at all.

  As described above, when a phosphate ester plasticizer is included, it is not preferable because the base material is easily deformed when the actinic radiation curable resin layer is formed.

  The total content of the plasticizer in the cellulose ester film is preferably 5 to 20% by mass, more preferably 6 to 16% by mass, and particularly preferably 8 to 13% by mass with respect to the total solid content. The contents of the two kinds of plasticizers are each at least 1% by mass, preferably 2% by mass or more.

  The polyhydric alcohol ester plasticizer is preferably contained in an amount of 1 to 12% by mass, particularly preferably 3 to 11% by mass. If the amount is too small, deterioration of flatness is recognized, and if it is too large, bleeding out tends to occur. The mass ratio between the polyhydric alcohol ester plasticizer and the other plasticizer is preferably in the range of 1: 4 to 4: 1, more preferably 1: 3 to 3: 1. If the amount of the plasticizer added is too large or too small, the film is liable to be deformed, which is not preferable.

<Ultraviolet absorber>
The cellulose ester film according to the present invention contains an ultraviolet absorber. The ultraviolet absorber is intended to improve durability by absorbing ultraviolet light having a wavelength of 400 nm or less, and the transmittance at a wavelength of 370 nm is particularly preferably 10% or less, more preferably 5% or less. Preferably it is 2% or less.

  Although the ultraviolet absorber used in the present invention is not particularly limited, for example, oxybenzophenone compounds, benzotriazole compounds, salicylic acid ester compounds, benzophenone compounds, cyanoacrylate compounds, triazine compounds, nickel complex compounds, inorganic powders Examples include the body.

  UV absorbers preferably used are benzotriazole-based UV absorbers and benzophenone-based UV absorbers that are highly transparent and excellent in preventing the deterioration of polarizing plates and liquid crystal elements, and have less unnecessary coloration. UV absorbers are particularly preferred. Specific examples of the ultraviolet absorber used in the present invention include, for example, 5-chloro-2- (3,5-di-sec-butyl-2-hydroxylphenyl) -2H-benzotriazole, (2-2H-benzotriazole -2-yl) -6- (linear and side chain dodecyl) -4-methylphenol, 2-hydroxy-4-benzyloxybenzophenone, 2,4-benzyloxybenzophenone, etc., and tinuvin 109, tinuvin 171 Tinuvin such as Tinuvin 234, Tinuvin 326, Tinuvin 327, Tinuvin 328, etc., all of which are commercially available products from Ciba Specialty Chemicals and can be used preferably.

  Further, triazine compounds represented by the general formula (I) of JP-A-2001-235621 are also preferably used for the cellulose ester film according to the present invention.

  The cellulose ester film according to the present invention preferably contains two or more ultraviolet absorbers.

  As the UV absorber, a polymer UV absorber can be preferably used, and in particular, a polymer type UV absorber described in JP-A-6-148430 is preferably used.

  The method of adding the UV absorber may be added to the dope after the UV absorber is dissolved in an alcohol such as methanol, ethanol or butanol, an organic solvent such as methylene chloride, methyl acetate, acetone or dioxolane, or a mixed solvent thereof. Or you may add directly in dope composition. For an inorganic powder that does not dissolve in an organic solvent, a dissolver or a sand mill is used in the organic solvent and cellulose ester to disperse and then added to the dope.

  The amount of UV absorber used is not uniform depending on the type of UV absorber, operating conditions, etc., but when the dry film thickness of the cellulose ester film is 30 to 200 μm, it is 0.5 to 4 with respect to the cellulose ester film. 0.0 mass% is preferable, and 0.6 g-2.0 mass% is still more preferable.

<Fine particles>
The cellulose ester film according to the present invention preferably contains fine particles.

  As fine particles used in the present invention, examples of inorganic compounds include silicon dioxide, titanium dioxide, aluminum oxide, zirconium oxide, calcium carbonate, calcium carbonate, talc, clay, calcined kaolin, calcined calcium silicate, and hydrated silicic acid. Mention may be made of calcium, aluminum silicate, magnesium silicate and calcium phosphate. Fine particles containing silicon are preferable in terms of low turbidity, and silicon dioxide is particularly preferable.

  The average primary particle diameter of the fine particles is preferably 5 to 50 nm, and more preferably 7 to 20 nm. These are preferably contained mainly as secondary aggregates having a particle size of 0.05 to 0.3 μm. The content of these fine particles in the cellulose ester film is preferably 0.05 to 1% by mass, particularly preferably 0.1 to 0.5% by mass. In the case of a cellulose ester film having a multilayer structure by the co-casting method, it is preferable to contain fine particles of this addition amount on the surface.

  Silicon dioxide fine particles are commercially available, for example, under the trade names Aerosil R972, R972V, R974, R812, 200, 200V, 300, R202, OX50, TT600 (above Nippon Aerosil Co., Ltd.). I can do it.

  Zirconium oxide fine particles are commercially available under the trade names of Aerosil R976 and R811 (manufactured by Nippon Aerosil Co., Ltd.) and can be used.

  Examples of the polymer include silicone resin, fluorine resin, and acrylic resin. Silicone resins are preferable, and those having a three-dimensional network structure are particularly preferable. For example, Tospearl 103, 105, 108, 120, 145, 3120, and 240 (manufactured by Toshiba Silicone Co., Ltd.) It is marketed by name and can be used.

  Among these, Aerosil 200V and Aerosil R972V are particularly preferably used because they have a large effect of reducing the friction coefficient while keeping the turbidity of the cellulose ester film low. In the cellulose ester film used in the present invention, the dynamic friction coefficient on the back side of the actinic radiation curable resin layer is preferably 1.0 or less.

<dye>
A dye may be added to the cellulose ester film used in the present invention to adjust the color. For example, a blue dye may be added to suppress the yellowness of the film. Preferred examples of the dye include anthraquinone dyes.

  The anthraquinone dye may have an arbitrary substituent at an arbitrary position from the 1st position to the 8th position of the anthraquinone. Preferred substituents include an anilino group, hydroxyl group, amino group, nitro group, or hydrogen atom. In particular, it is preferable to contain a blue dye described in paragraphs [0034] to [0037] of JP-A No. 2001-154017, particularly an anthraquinone dye.

  Various additives may be batch-added to a dope that is a cellulose ester-containing solution before film formation, or an additive solution may be separately prepared and added in-line. In particular, it is preferable to add a part or all of the fine particles in-line in order to reduce the load on the filter medium.

  When the additive solution is added in-line, it is preferable to dissolve a small amount of cellulose ester in order to improve mixing with the dope. The amount of the cellulose ester is preferably 1 to 10 parts by mass, more preferably 3 to 5 parts by mass with respect to 100 parts by mass of the solvent.

  In order to perform in-line addition and mixing in the present invention, for example, an in-line mixer such as a static mixer (manufactured by Toray Engineering), SWJ (Toray static type in-tube mixer Hi-Mixer) or the like is preferably used.

<Method for producing cellulose ester film>
Next, the manufacturing method of the cellulose-ester film of this invention is demonstrated.

  The cellulose ester film of the present invention is prepared by dissolving a cellulose ester and an additive in a solvent to prepare a dope, casting a dope on a belt-shaped or drum-shaped metal support, and casting the dope. It is carried out by a step of drying as a web, a step of peeling from a metal support, a step of stretching or maintaining the width, a step of further drying, and a step of winding up the finished film.

  The process for preparing the dope will be described. The concentration of cellulose ester in the dope is preferably higher because the drying load after casting on the metal support can be reduced. However, if the concentration of cellulose ester is too high, the load during filtration increases and the filtration accuracy increases. Becomes worse. As a density | concentration which makes these compatible, 10-35 mass% is preferable, More preferably, it is 15-25 mass%.

  The solvent used in the dope of the present invention may be used alone or in combination of two or more. However, it is preferable from the viewpoint of production efficiency that a good solvent and a poor solvent of cellulose ester are mixed and used. The more solvent is preferable from the viewpoint of solubility of the cellulose ester. The preferable range of the mixing ratio of the good solvent and the poor solvent is 70 to 98% by mass for the good solvent and 2 to 30% by mass for the poor solvent. With a good solvent and a poor solvent, what dissolve | melts the cellulose ester to be used independently is defined as a good solvent, and what poorly swells or does not melt | dissolve is defined as a poor solvent. Therefore, depending on the acyl group substitution degree of the cellulose ester, the good solvent and the poor solvent change. For example, when acetone is used as the solvent, the cellulose ester acetate ester (acetyl group substitution degree 2.4) and the cellulose acetate propionate are good. As a solvent, cellulose acetate (acetyl group substitution degree 2.8) is a poor solvent.

  Although the good solvent used for this invention is not specifically limited, Organic halogen compounds, such as a methylene chloride, dioxolanes, acetone, methyl acetate, methyl acetoacetate, etc. are mentioned. Particularly preferred is methylene chloride or methyl acetate.

  Moreover, although the poor solvent used for this invention is not specifically limited, For example, methanol, ethanol, n-butanol, cyclohexane, cyclohexanone, etc. are used preferably. Moreover, it is preferable that 0.01-2 mass% of water contains in dope.

  A general method can be used as a method of dissolving the cellulose ester when preparing the dope described above. When heating and pressurization are combined, it is possible to heat above the boiling point at normal pressure. It is preferable to stir and dissolve while heating at a temperature that is equal to or higher than the boiling point of the solvent at normal pressure and that the solvent does not boil under pressure, in order to prevent the generation of massive undissolved materials called gels and mamaco. Moreover, after mixing a cellulose ester with a poor solvent and making it wet or swell, the method of adding a good solvent and melt | dissolving is also used preferably.

  The pressurization may be performed by a method of injecting an inert gas such as nitrogen gas or a method of increasing the vapor pressure of the solvent by heating. Heating is preferably performed from the outside. For example, a jacket type is preferable because temperature control is easy.

  The heating temperature with the addition of the solvent is preferably higher from the viewpoint of the solubility of the cellulose ester, but if the heating temperature is too high, the required pressure increases and the productivity deteriorates. A preferable heating temperature is 45 to 120 ° C, more preferably 60 to 110 ° C, and still more preferably 70 ° C to 105 ° C. The pressure is adjusted so that the solvent does not boil at the set temperature.

  Alternatively, a cooling dissolution method is also preferably used, whereby the cellulose ester can be dissolved in a solvent such as methyl acetate.

  Next, this cellulose ester solution is filtered using a suitable filter medium such as filter paper. As the filter medium, it is preferable that the absolute filtration accuracy is small in order to remove insoluble matters and the like. However, if the absolute filtration accuracy is too small, there is a problem that the filter medium is likely to be clogged. For this reason, a filter medium with an absolute filtration accuracy of 0.008 mm or less is preferable, a filter medium with 0.001 to 0.008 mm is more preferable, and a filter medium with 0.003 to 0.006 mm is still more preferable.

  The material of the filter medium is not particularly limited, and a normal filter medium can be used. However, a plastic filter medium such as polypropylene and Teflon (R) and a metal filter medium such as stainless steel are preferable because there is no loss of fibers. . It is preferable to remove and reduce impurities, particularly bright spot foreign matter, contained in the raw material cellulose ester by filtration.

A bright spot foreign substance is when two polarizing plates are placed in a crossed Nicol state, a cellulose ester film is placed between them, light is applied from the side of one polarizing plate, and observed from the side of the other polarizing plate. It is a point (foreign matter) where light from the opposite side appears to leak, and the number of bright spots having a diameter of 0.01 mm or more is preferably 200 / cm ² or less. More preferably, it is 100 pieces / cm < ² > or less, More preferably, it is 50 pieces / m < ² > or less, More preferably, it is 0-10 pieces / cm < ² > or less. Further, it is preferable that the number of bright spots of 0.01 mm or less is small.

  The dope can be filtered by an ordinary method, but the method of filtering while heating at a temperature not lower than the boiling point of the solvent at normal pressure and in a range where the solvent does not boil under pressure is the filtration pressure before and after filtration. The increase in the difference (referred to as differential pressure) is small and preferable. A preferred temperature is 45 to 120 ° C, more preferably 45 to 70 ° C, and still more preferably 45 to 55 ° C.

  A smaller filtration pressure is preferred. The filtration pressure is preferably 1.6 MPa or less, more preferably 1.2 MPa or less, and further preferably 1.0 MPa or less.

  Here, the dope casting will be described.

  The metal support in the casting (casting) step preferably has a mirror-finished surface, and a stainless steel belt or a drum whose surface is plated with a casting is preferably used as the metal support. The cast width can be 1 to 4 m. The surface temperature of the metal support in the casting step is set to −50 ° C. to a temperature at which the solvent boils and does not foam. A higher temperature is preferable because the web can be dried faster, but if it is too high, the web may foam or the flatness may deteriorate. The preferable support temperature is appropriately determined at 0 to 100 ° C, and more preferably 5 to 30 ° C. Alternatively, it is also a preferable method that the web is gelled by cooling and peeled from the drum in a state containing a large amount of residual solvent. The method for controlling the temperature of the metal support is not particularly limited, and there are a method of blowing hot air or cold air, and a method of contacting hot water with the back side of the metal support. It is preferable to use warm water because heat transfer is performed efficiently, so that the time until the temperature of the metal support becomes constant is short. When using warm air, considering the temperature drop of the web due to the latent heat of vaporization of the solvent, while using warm air above the boiling point of the solvent, there may be cases where wind at a temperature higher than the target temperature is used while preventing foaming. . In particular, it is preferable to perform drying efficiently by changing the temperature of the support and the temperature of the drying air during the period from casting to peeling.

  In order for the cellulose ester film to exhibit good flatness, the residual solvent amount when peeling the web from the metal support is preferably 10 to 150% by mass, more preferably 20 to 40% by mass or 60 to 130% by mass. Especially preferably, it is 20-30 mass% or 70-120 mass%.

  In the present invention, the amount of residual solvent is defined by the following formula.

Residual solvent amount (% by mass) = {(MN) / N} × 100
M is the mass of a sample collected during or after the production of the web or film, and N is the mass after heating M at 115 ° C. for 1 hour.

  Further, in the drying step of the cellulose ester film, the web is peeled off from the metal support, and further dried, and the residual solvent amount is preferably 1% by mass or less, more preferably 0.1% by mass or less, Especially preferably, it is 0-0.01 mass% or less.

  In the film drying process, generally, a roll drying method (a method in which a plurality of rolls arranged on the upper and lower sides are alternately passed through and dried) or a method of drying while transporting the web by a tenter method is adopted.

  In order to produce the cellulose ester film for an antireflection film of the present invention, the web is stretched in the conveying direction immediately after peeling from the metal support where the amount of residual solvent is large, and both ends of the web are held with clips or the like. It is particularly preferable to perform stretching in the width direction by a tenter method. The preferred draw ratio in both the machine direction and the transverse direction is 1.05 to 1.3 times, and more preferably 1.05 to 1.15 times. It is preferable that the area is 1.12 times to 1.44 times, and preferably 1.15 times to 1.32 times due to longitudinal and lateral stretching. This can be determined by the draw ratio in the longitudinal direction × the draw ratio in the transverse direction. If one of the draw ratios in the machine direction and the transverse direction is less than 1.05 times, the deterioration of the flatness due to ultraviolet irradiation when forming the actinic radiation curable resin layer is not preferable. Moreover, even if a draw ratio exceeds 1.3 times, since planarity deteriorates and haze also increases, it is not preferable.

  In order to stretch in the machine direction immediately after peeling, it is preferable to stretch by peeling tension and subsequent transport tension. For example, it is preferable to peel at a peeling tension of 210 N / m or more, and particularly preferably 220 to 300 N / m.

  The means for drying the web is not particularly limited, and can be generally performed with hot air, infrared rays, a heating roll, microwave, or the like, but it is preferably performed with hot air in terms of simplicity.

  The drying temperature in the web drying step is preferably increased stepwise from 30 to 150 ° C, and more preferably from 50 to 140 ° C in order to improve dimensional stability.

  Although the film thickness of a cellulose-ester film is not specifically limited, 10-200 micrometers is used preferably. In particular, it was difficult to obtain an antireflection film excellent in flatness and hardness with a thin film of 10 to 70 μm, but according to the present invention, a thin antireflection film excellent in flatness and hardness was obtained, Moreover, since it is excellent also in productivity, it is especially preferable that the film thickness of a cellulose-ester film is 10-70 micrometers. More preferably, it is 20-60 micrometers. Most preferably, it is 35-60 micrometers. Moreover, the cellulose ester film made into the multilayer structure by the co-casting method can also be used preferably. Even when the cellulose ester has a multilayer structure, it has a layer containing an ultraviolet absorber and a plasticizer, and it may be a core layer, a skin layer, or both.

  The antireflection film of the present invention preferably has a width of 1 to 4 m. Moreover, the centerline average roughness (Ra) of the surface which provides the active ray cured resin layer of a cellulose-ester film can use a 0.001-1 micrometer thing.

  When the width of the cellulose ester film becomes wider, the illuminance unevenness of the irradiated light at the time of UV curing cannot be ignored, not only the flatness is deteriorated, but also the unevenness of the hardness occurs, and when the antireflection layer is formed on this, the uneven reflection is generated. There was a problem of becoming prominent. Since the antireflection film of the present invention can provide sufficient hardness with a small dose, even if there is unevenness in the width direction of the irradiated light, unevenness in the width direction is less likely to occur, and the reflection is excellent in flatness. Since a prevention film is obtained, a remarkable effect is recognized with a wide cellulose ester film. In particular, those having a width of 1.4 to 4 m are preferably used, and particularly preferably 1.4 to 2 m. If it exceeds 4 m, conveyance becomes difficult.

<Physical properties>
The moisture permeability of the cellulose ester film used in the present invention, 40 ° C., or less 850g / m ² · 24h at 90% RH, preferably ^{20~800g / m 2 · 24h, 20~750g} / m 2 · 24 h is particularly preferable. The moisture permeability can be measured according to the method described in JIS Z 0208.

  The cellulose ester film used in the present invention has a breaking elongation measured by the following measurement of preferably 10 to 80%, more preferably 20 to 50%.

(Measurement of elongation at break)
A film containing an arbitrary residual solvent is cut into a sample width of 10 mm and a length of 130 mm, and stored for 24 hours at 23 ° C. and 55% RH, and a tensile test is performed at a pulling speed of 100 mm / min with a chuck distance of 100 mm. be able to.

  The visible light transmittance of the cellulose ester film used in the present invention as measured by the following measurement is preferably 90% or more, and more preferably 93% or more.

(Measurement of transmittance)
The transmittance T is 380, 400, 500 nm from the spectral transmittance τ (λ) obtained every 10 nm in the wavelength region of 350-700 nm using a spectral altimeter U-3400 (Hitachi, Ltd.). Transmittance can be calculated.

  The haze by the following measurement of the cellulose ester film used in the present invention is preferably less than 1%, particularly preferably 0 to 0.1%.

(Haze value)
According to JIS K-6714, it can be measured using a haze meter (1001DP type, manufactured by Nippon Denshoku Industries Co., Ltd.) and used as an index of transparency.

  The in-plane retardation value (Ro) of the cellulose ester film used in the present invention is preferably 0 to 70 nm or less. More preferably, it is 0-30 nm or less, More preferably, it is 0-10 nm or less. The retardation value (Rt) in the film thickness direction is preferably 0 to 400 nm, preferably 10 to 200 nm, and more preferably 30 to 150 nm.

  The retardation value (Ro) (Rt) can be obtained by the following equation.

Ro = (nx−ny) × d
Rt = ((nx + ny) / 2−nz) × d
Here, d is the thickness (nm) of the film, the refractive index nx (also referred to as the maximum refractive index in the plane of the film, the refractive index in the slow axis direction), ny (in the direction perpendicular to the slow axis in the film plane). ) (Refractive index of film in the thickness direction).

  The retardation values (Ro) and (Rt) and the slow axis angle can be measured using an automatic birefringence meter. For example, the wavelength can be obtained at 590 nm in an environment of 23 ° C. and 55% RH using KOBRA-21ADH (Oji Scientific Instruments).

  The slow axis is preferably in the width direction ± 1 ° of the film or in the longitudinal direction ± 1 °.

  Next, the production of the antireflection film according to the present invention using the cellulose ester as a base material will be described in detail.

<Actinic radiation curable resin layer>
A method for applying an actinic radiation curable resin layer to the antireflection film of the present invention will be described.

  The actinic radiation curable resin layer refers to a layer mainly composed of a resin that cures through a crosslinking reaction or the like by irradiation with actinic rays such as ultraviolet rays or electron beams. As the actinic radiation curable resin, a component containing a monomer having an ethylenically unsaturated double bond is preferably used, and an actinic radiation curable resin layer is formed by curing by irradiation with actinic radiation such as ultraviolet rays or electron beams. The Typical examples of the actinic radiation curable resin include an ultraviolet curable resin and an electron beam curable resin, and a resin curable by ultraviolet irradiation is preferable.

  As the ultraviolet curable resin, for example, an ultraviolet curable urethane acrylate resin, an ultraviolet curable polyester acrylate resin, an ultraviolet curable epoxy acrylate resin, an ultraviolet curable polyol acrylate resin, or an ultraviolet curable epoxy resin is preferable. Used.

  UV curable acrylic urethane resins generally include 2-hydroxyethyl acrylate and 2-hydroxyethyl methacrylate (hereinafter referred to as acrylates) in products obtained by reacting polyester polyols with isocyanate monomers or prepolymers. It can be easily obtained by reacting an acrylate monomer having a hydroxyl group such as 2-hydroxypropyl acrylate. For example, those described in JP-A-59-151110 can be used.

  For example, a mixture of 100 parts Unidic 17-806 (Dainippon Ink Co., Ltd.) and 1 part Coronate L (Nihon Polyurethane Co., Ltd.) is preferably used.

  Examples of UV curable polyester acrylate resins include those that are easily formed when 2-hydroxyethyl acrylate and 2-hydroxy acrylate monomers are generally reacted with polyester polyols. JP-A-59-151112 Can be used.

  Specific examples of the ultraviolet curable epoxy acrylate resin include an epoxy acrylate as an oligomer, a reactive diluent and a photoreaction initiator added thereto, and reacted to form an oligomer. The thing as described in 105738 can be used.

  Specific examples of UV curable polyol acrylate resins include trimethylolpropane triacrylate, ditrimethylolpropane tetraacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, dipentaerythritol hexaacrylate, alkyl-modified dipentaerythritol pentaacrylate, etc. I can list them.

  Specific examples of the photoreaction initiator of these ultraviolet curable resins include benzoin and its derivatives, acetophenone, benzophenone, hydroxybenzophenone, Michler's ketone, α-amyloxime ester, thioxanthone, and derivatives thereof. You may use with a photosensitizer. The photoinitiator can also be used as a photosensitizer. In addition, when using an epoxy acrylate photoinitiator, a sensitizer such as n-butylamine, triethylamine, or tri-n-butylphosphine can be used. The photoreaction initiator or photosensitizer used in the ultraviolet curable resin composition is 0.1 to 15 parts by weight, preferably 1 to 10 parts by weight, based on 100 parts by weight of the composition.

  Examples of the resin monomer include general monomers such as methyl acrylate, ethyl acrylate, butyl acrylate, benzyl acrylate, cyclohexyl acrylate, vinyl acetate, and styrene as monomers having one unsaturated double bond. In addition, monomers having two or more unsaturated double bonds include ethylene glycol diacrylate, propylene glycol diacrylate, divinylbenzene, 1,4-cyclohexane diacrylate, 1,4-cyclohexyldimethyl adiacrylate, and the above trimethylolpropane. Examples thereof include triacrylate and pentaerythritol tetraacryl ester.

  Examples of commercially available ultraviolet curable resins that can be used in the present invention include ADEKA OPTMER KR / BY series: KR-400, KR-410, KR-550, KR-566, KR-567, BY-320B (Asahi Denka ( Co., Ltd.); Koeihard A-101-KK, A-101-WS, C-302, C-401-N, C-501, M-101, M-102, T-102, D-102, NS -101, FT-102Q8, MAG-1-P20, AG-106, M-101-C (manufactured by Guangei Chemical Co., Ltd.); Seika Beam PHC2210 (S), PHC X-9 (K-3), PHC2213, DP -10, DP-20, DP-30, P1000, P1100, P1200, P1300, P1400, P1500, P1600, SCR900 (manufactured by Dainichi Seika Kogyo Co., Ltd.) KRM7033, KRM7039, KRM7130, KRM7131, UVECRYL29201, UVECRYL29202 (manufactured by Daicel UCB Corporation); RC-5015, RC-5016, RC-5020, RC-5031, RC-5100, RC-5102, RC-5120 RC-5122, RC-5152, RC-5171, RC-5180, RC-5181 (manufactured by Dainippon Ink & Chemicals, Inc.); 340 clear (manufactured by China Paint Co., Ltd.); Sunrad H-601, RC-750, RC-700, RC-600, RC-500, RC-611, RC-612 (manufactured by Sanyo Chemical Industries); SP -1509, SP-1507 (manufactured by Showa Polymer Co., Ltd.); RCC-15C (manufactured by Grace Japan Co., Ltd.), Aronix M-6100, M-8030, M-8060 (manufactured by Toagosei Co., Ltd.), etc. Can be selected as appropriate.

  Specific examples of compounds include trimethylolpropane triacrylate, ditrimethylolpropane tetraacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, dipentaerythritol hexaacrylate, alkyl-modified dipentaerythritol pentaacrylate, and the like. .

  The cured resin layer thus obtained may contain fine particles of an inorganic compound or an organic compound in order to adjust the scratch resistance, slipperiness and refractive index, and to impart antiglare properties to the produced antireflection film.

  Examples of the inorganic fine particles used in the actinic ray curable resin layer include silicon oxide, titanium oxide, aluminum oxide, tin oxide, indium oxide, ITO, zinc oxide, zirconium oxide, magnesium oxide, calcium carbonate, calcium carbonate, talc, clay, Examples include calcined kaolin, calcined calcium silicate, hydrated calcium silicate, aluminum silicate, magnesium silicate and calcium phosphate. In particular, silicon oxide, titanium oxide, aluminum oxide, zirconium oxide, magnesium oxide and the like are preferably used.

  Organic particles include polymethacrylic acid methyl acrylate resin powder, acrylic styrene resin powder, polymethyl methacrylate resin powder, silicon resin powder, polystyrene resin powder, polycarbonate resin powder, benzoguanamine resin powder, melamine resin powder. Polyolefin resin powder, polyester resin powder, polyamide resin powder, polyimide resin powder, or polyfluoroethylene resin powder can be added to the ultraviolet curable resin composition. Particularly preferred are cross-linked polystyrene particles (for example, SX-130H, SX-200H, SX-350H, manufactured by Soken Chemical) and polymethyl methacrylate-based particles (for example, MX150, MX300, manufactured by Soken Chemical).

  The average particle size of these fine particle powders is preferably from 0.01 to 5 μm, more preferably from 0.1 to 5.0 μm, and even more preferably from 0.1 to 4.0 μm. Moreover, it is preferable to contain 2 or more types of microparticles | fine-particles from which a particle size differs. The proportion of the ultraviolet curable resin composition and the fine particles is desirably blended so as to be 0.1 to 30 parts by mass with respect to 100 parts by mass of the resin composition.

  The UV curable resin layer is a clear hard coat layer having a center line average roughness (Ra) defined by JIS B 0601 of 0.001 to 0.1 μm, or an anti-glare layer having Ra of about 0.1 to 1 μm. A layer is preferred. The center line average roughness (Ra) is preferably measured with an optical interference type surface roughness measuring instrument, and can be measured using, for example, a non-contact surface fine shape measuring device WYKO NT-2000 manufactured by WYKO.

(Refractive index of actinic radiation curable resin layer)
The refractive index of the actinic radiation curable resin layer according to the present invention is preferably 1.5 to 2.0, particularly preferably 1.6 to 1.7 from the viewpoint of optical design for obtaining a low reflective film. . The refractive index of the actinic radiation curable resin layer can be adjusted depending on the refractive index and content of the fine particles to be added or the inorganic binder.

(Film thickness of actinic radiation curable resin layer)
From the viewpoint of imparting sufficient durability and impact resistance, the thickness of the actinic radiation curable resin layer is preferably in the range of 0.5 μm to 10 μm, and more preferably 1 μm to 5 μm.

  These actinic ray curable resin layers can be coated by a known method such as a gravure coater, a dip coater, a reverse coater, a wire bar coater, a die coater, or an ink jet method.

As a light source for curing an ultraviolet curable resin by a photocuring reaction to form a cured film layer, any light source that generates ultraviolet rays can be used without any limitation. For example, a low pressure mercury lamp, a medium pressure mercury lamp, a high pressure mercury lamp, an ultrahigh pressure mercury lamp, a carbon arc lamp, a metal halide lamp, a xenon lamp, or the like can be used. Irradiation conditions vary depending on each lamp, but the irradiation amount of active rays is usually 5 to 500 mJ / cm ² , preferably 5 to 100 mJ / cm ² , and particularly preferably 20 to 80 mJ / cm ² .

  In the conventional antireflection film, an antireflection film having a pencil hardness of 4H or more and excellent flatness cannot be obtained at such a low irradiation amount. In the case of an antireflection film that does not require much hardness, the amount of irradiation can be further reduced, so that the antireflection film can be manufactured at a speed far exceeding the coating speed limited by the ability of the ultraviolet irradiation section, and the productivity Is significantly improved. Moreover, when adding an inorganic fine particle or an inorganic binder to the actinic radiation curable resin layer to increase the refractive index or impart conductivity, it is necessary to remarkably increase the amount of UV irradiation, which causes the flatness of the film to deteriorate. It became one of. In particular, in wide films with a width of 1.4 to 4 m and thin films with a thickness of 10 to 70 μm, the flatness deterioration was remarkable, but the present invention can reduce the conventional irradiation amount, and the flatness An excellent antireflection film was obtained.

  Moreover, when irradiating actinic radiation, it is preferable to carry out while applying tension | tensile_strength in the conveyance direction of a film, More preferably, it is performing applying tension | tensile_strength also in the width direction. The tension to be applied is preferably 30 to 300 N / m. The method for applying the tension is not particularly limited, and the tension may be applied in the conveying direction on the back roll, or the tension may be applied in the width direction or the biaxial direction by a tenter. This makes it possible to obtain a film having further excellent flatness.

  The ultraviolet curable resin layer composition coating solution may contain a solvent, or may be appropriately contained and diluted as necessary. Examples of the organic solvent contained in the coating liquid include hydrocarbons (toluene, xylene), alcohols (methanol, ethanol, isopropanol, butanol, cyclohexanol), ketones (acetone, methyl ethyl ketone, methyl isobutyl ketone), It can be appropriately selected from esters (methyl acetate, ethyl acetate, methyl lactate), glycol ethers, and other organic solvents, or a mixture thereof can be used. Propylene glycol monoalkyl ether (1 to 4 carbon atoms of the alkyl group) or propylene glycol monoalkyl ether acetate ester (1 to 4 carbon atoms of the alkyl group) is 5% by mass or more, more preferably 5 to 80%. It is preferable to use the organic solvent containing at least mass%.

  In addition, it is particularly preferable to add a silicon compound to the ultraviolet curable resin layer composition coating solution. For example, polyether-modified silicone oil is preferably added. The number average molecular weight of the polyether-modified silicone oil is, for example, 1,000 to 100,000, preferably 2,000 to 50,000. When the number average molecular weight is less than 1,000, the coating film is dried. On the contrary, when the number average molecular weight exceeds 100,000, it tends to be difficult to bleed out on the surface of the coating film.

  Commercially available silicon compounds include DKQ8-779 (trade name, manufactured by Dow Corning), SF3771, SF8410, SF8411, SF8419, SF8421, SF8428, SH200, SH510, SH1107, SH3749, SH3771, BX16-034, SH3746, SH3749, SH8400, SH3771M, SH3772M, SH3773M, SH3775M, BY-16-837, BY-16-839, BY-16-869, BY-16-870, BY-16-004, BY-16-891, BY-16 872, BY-16-874, BY22-008M, BY22-012M, FS-1265 (above, product names manufactured by Toray Dow Corning Silicone), KF-101, KF-100T, KF351, KF3 2, KF353, KF354, KF355, KF615, KF618, KF945, KF6004, Silicone X-22-945, X22-160AS (trade name, manufactured by Shin-Etsu Chemical Co., Ltd.), XF3940, XF3949 (trade name, manufactured by Toshiba Silicone Co., Ltd.) ), Disparon LS-009 (manufactured by Enomoto Kasei Co., Ltd.), Granol 410 (manufactured by Kyoeisha Yushi Chemical Co., Ltd.), TSF4440, TSF4441, TSF4445, TSF4446, TSF4452, TSF4460 (manufactured by GE Toshiba Silicone), BYK-306, BYK- 330, BYK-307, BYK-341, BYK-344, BYK-361 (manufactured by BYK-Japan) L series (for example, L7001, L-7006, L-7604, L-9000) manufactured by Nippon Unicar Co., Ltd. Y Over's, FZ series (FZ-2203, FZ-2206, FZ-2207) and the like, are preferably used.

  These components enhance the applicability to the substrate and the lower layer. When added to the outermost surface layer of the laminate, it not only improves the water repellency, oil repellency and antifouling properties of the coating film, but also exhibits an effect on the scratch resistance of the surface. These components are preferably added in a range of 0.01 to 3% by mass with respect to the solid component in the coating solution.

  As a coating method of the ultraviolet curable resin composition coating solution, the above-described methods can be used. The coating amount is suitably 0.1 to 30 μm, preferably 0.5 to 15 μm, as the wet film thickness. Moreover, as a dry film thickness, it is an average film thickness of 0.1-15 micrometers, Preferably it is 1-5 micrometers.

  The ultraviolet curable resin composition is preferably irradiated with ultraviolet rays during or after coating and drying, and the irradiation time for obtaining the necessary irradiation amount of active rays is preferably about 0.1 seconds to 1 minute, and is cured by ultraviolet rays. From the viewpoint of the curing efficiency or work efficiency of the functional resin, 0.1 to 10 seconds is more preferable.

Moreover, it is preferable that the illuminance of these active ray irradiation parts is 50-150 mW / m < ² >.

  The hard coat layer (ultraviolet curable resin layer) may contain metal oxide fine particles.

  The metal oxide contained is metal oxide fine particles selected from Zr, Sn, Sb, As, Zn, Nb, In, and Al, and is preferably a conductive layer. Accordingly, it is preferable that the hard coat layer functions as an antistatic layer or an electromagnetic ray shielding layer.

  A particularly preferable metal oxide is an oxide such as Sn, In, or Zn, and a conductive layer such as indium tin oxide known as so-called ITO is particularly preferable.

  The amount of metal oxide varies depending on the type of metal oxide used, but when used as an antistatic layer, it is added so as to have a specific resistance value of 0.01 to 500 Ω / □, more preferably 0.01 to 10 Ω / □. It is preferable to do. The ratio of the ultraviolet curable resin composition and the fine particles is in the range of 0.1 to 30 parts by mass with respect to 100 parts by mass of the resin composition.

Further, as described in JP-A-9-222504, JP-A-9-220791, JP-A-9-222602, etc., for example, TiO ₂ or the like is used so that the hard coat layer has a role as a high refractive index layer. A component (metal oxide fine particles) for forming the high refractive index layer may be contained. In this case, an antireflection layer having a simple configuration by optical interference is formed by coating the low refractive index layer on the high refractive index layer. In this case, the amount of the metal oxide forming the high refractive index layer such as TiO ₂ is the same as that in the high refractive index layer described later.

  Furthermore, when the above-mentioned low refractive index layer is provided directly or via another layer, the hard coat layer has a hydrophobic group represented by (C) as dimethylpolysiloxane and a hydrophilic group as poly. It is preferable to contain a nonionic surfactant composed of an oxyalkylene group. Compared with the case where it is added only to the low refractive layer, it is possible to achieve a reduction in coating unevenness due to uniform dispersion of the silica particles in the lower reflectance layer. The amount of the surfactant represented by (C) is preferably 0.001 to 5 parts by mass, and particularly preferably 0.003 to 3 parts by mass with respect to the hard coat layer composition (solid content). is there.

  The hard coat layer may have a multilayer structure of two or more layers. One of the layers may be, for example, the above-mentioned conductive fine particles or a so-called antistatic layer containing an ionic polymer, or a color tone adjusting agent having a color tone adjusting function as a color correction filter for various display elements. It may be contained, or it is preferable to contain an electromagnetic wave blocking agent or an infrared absorber so as to have each function.

  Here, as a filter for color correction, for example, in the case of a plasma display panel, the color balance of the display color is excluded except for extra light (wavelength in the range of 560 to 620 nm) included in light emission from the three primary color phosphors. A color tone adjusting agent for correcting the above is contained. Regarding the dyes or pigments used as these optical filters, JP-A-58-153904, JP-A-60-18749, JP-A-3-231988, JP-A-5-205643, JP-A-9-145918, JP-A-10-26704, It describes in Unexamined-Japanese-Patent No. 2001-91734, Unexamined-Japanese-Patent No. 2001-201629, etc. The color correction filter is not limited to the color tone adjustment of the PDP panel, but includes a filter having a color tone adjustment function in various wavelength regions required for other display devices.

  Examples of the electromagnetic wave blocking agent are described in JP-A-9-306366, JP-A-2001-201629, and the like. For example, this is a thin film having a surface resistance of about 100 mm by sputtering silver or an inorganic oxide. In this way, for example, electromagnetic waves in the frequency range of 30 MHz to 130 MHz leaking from the plasma display panel are shielded, and in the near infrared region (800 to 1000 nm) also emitted from the plasma display panel. Block line spectrum.

  The infrared absorber is preferably a dye or pigment having absorption in the infrared region, and examples thereof include dyes and pigments described in JP-A Nos. 2001-194522 and 2001-201629. As the amount of these dyes or pigments, the amount necessary for correction or the amount necessary for blocking may be selected, and varies depending on the type of dye or pigment used, but the transmittance at 800 nm is 15% or less, It is preferably used so that the transmittance at 850 nm is 5% or less.

<Back coat layer>
It is preferable to provide a back coat layer on the surface opposite to the side on which the actinic radiation curable resin layer is provided of the cellulose ester film serving as a substrate for producing the antireflection film of the present invention. The back coat layer is provided in order to correct curling caused by providing an actinic radiation curable resin layer or other layers. That is, the degree of curling can be balanced by imparting the property of being rounded with the surface on which the backcoat layer is provided facing inward. The back coat layer is preferably applied also as an anti-blocking layer. In that case, it is preferable that fine particles are added to the back coat layer coating composition in order to provide an anti-blocking function.

  As fine particles added to the back coat layer, examples of inorganic compounds include silicon dioxide, titanium dioxide, aluminum oxide, zirconium oxide, calcium carbonate, calcium carbonate, talc, clay, calcined kaolin, calcined calcium silicate, tin oxide, and oxidation. Mention may be made of indium, zinc oxide, ITO, hydrated calcium silicate, aluminum silicate, magnesium silicate and calcium phosphate. Fine particles containing silicon are preferable in terms of low haze, and silicon dioxide is particularly preferable.

  These fine particles are commercially available under the trade names of, for example, Aerosil R972, R972V, R974, R812, 200, 200V, 300, R202, OX50, and TT600 (manufactured by Nippon Aerosil Co., Ltd.). . Zirconium oxide fine particles are commercially available under the trade names of Aerosil R976 and R811 (manufactured by Nippon Aerosil Co., Ltd.) and can be used. Examples of the polymer include silicone resin, fluorine resin, and acrylic resin. Silicone resins are preferable, and those having a three-dimensional network structure are particularly preferable. For example, Tospearl 103, 105, 108, 120, 145, 3120, and 240 (manufactured by Toshiba Silicone Co., Ltd.) It is marketed by name and can be used.

  Among these, Aerosil 200V and Aerosil R972V are particularly preferably used because they have a large anti-blocking effect while keeping haze low. In the antireflection film used in the present invention, the dynamic friction coefficient on the back surface side of the actinic radiation curable resin layer is preferably 0.9 or less, particularly preferably 0.1 to 0.9.

  The fine particles contained in the backcoat layer are 0.1 to 50% by weight, preferably 0.1 to 10% by weight, based on the binder. When the back coat layer is provided, the increase in haze is preferably 1% or less, more preferably 0.5% or less, and particularly preferably 0.0 to 0.1%.

  Specifically, the back coat layer is formed by applying a composition containing a solvent for dissolving or swelling a cellulose ester film. The solvent used may include a solvent to be dissolved and / or a solvent to be swollen in addition to a solvent to be swelled, a composition in which these are mixed at an appropriate ratio depending on the degree of curling of the transparent resin film and the type of resin, and This is done using the coating amount.

  In order to enhance the curl prevention function, it is effective to increase the mixing ratio of the solvent for dissolving the solvent composition to be used and / or the solvent for swelling, and to decrease the ratio of the solvent not to be dissolved. This mixing ratio is preferably (solvent to be dissolved and / or solvent to be swollen) :( solvent to be dissolved) = 10: 0 to 1: 9. Examples of the solvent for dissolving or swelling the transparent resin film contained in such a mixed composition include dioxane, acetone, methyl ethyl ketone, N, N-dimethylformamide, methyl acetate, ethyl acetate, trichloroethylene, methylene chloride, and ethylene chloride. , Tetrachloroethane, trichloroethane, chloroform and the like. Examples of the solvent that does not dissolve include methanol, ethanol, n-propyl alcohol, i-propyl alcohol, n-butanol, cyclohexanol, and hydrocarbons (toluene, xylene).

  These coating compositions are preferably applied to the surface of the transparent resin film with a wet film thickness of 1 to 100 μm using a gravure coater, dip coater, reverse coater, wire bar coater, die coater, spray coating, ink jet coating or the like. Is particularly preferably 5 to 30 μm. Examples of the resin used as the binder of the backcoat layer include vinyl chloride-vinyl acetate copolymer, vinyl chloride resin, vinyl acetate resin, vinyl acetate-vinyl alcohol copolymer, partially hydrolyzed vinyl chloride-vinyl acetate copolymer. Polymer, vinyl chloride-vinylidene chloride copolymer, vinyl chloride-acrylonitrile copolymer, ethylene-vinyl alcohol copolymer, chlorinated polyvinyl chloride, ethylene-vinyl chloride copolymer, ethylene-vinyl acetate copolymer, etc. Vinyl polymer or copolymer, nitrocellulose, cellulose acetate propionate (preferably acetyl group substitution degree 1.8-2.3, propionyl group substitution degree 0.1-1.0), diacetyl cellulose, cellulose Cellulose derivatives such as acetate butyrate resin, maleic acid and / or Or acrylic acid copolymer, acrylic ester copolymer, acrylonitrile-styrene copolymer, chlorinated polyethylene, acrylonitrile-chlorinated polyethylene-styrene copolymer, methyl methacrylate-butadiene-styrene copolymer, acrylic resin Rubber resins such as polyvinyl acetal resin, polyvinyl butyral resin, polyester polyurethane resin, polyether polyurethane resin, polycarbonate polyurethane resin, polyester resin, polyether resin, polyamide resin, amino resin, styrene-butadiene resin, butadiene-acrylonitrile resin, Examples thereof include, but are not limited to, silicone resins and fluorine resins. For example, as an acrylic resin, Acrypet MD, VH, MF, V (manufactured by Mitsubishi Rayon Co., Ltd.), Hyperl M-4003, M-4005, M-4006, M-4202, M-5000, M-5001, M-4501 (manufactured by Negami Kogyo Co., Ltd.), Dialnal BR-50, BR-52, BR-53, BR-60, BR-64, BR-73, BR-75, BR-77, BR-79, BR -80, BR-82, BR-83, BR-85, BR-87, BR-88, BR-90, BR-93, BR-95, BR-100, BR-101, BR-102, BR-105 BR-106, BR-107, BR-108, BR-112, BR-113, BR-115, BR-116, BR-117, BR-118, etc. (Mitsubishi Rayon Co., Ltd.) acrylic and The methacrylic monomers such as various homopolymers and copolymers were prepared as raw materials are commercially available, can also be selected preferred mono from this appropriate.

  Particularly preferred are cellulose resin layers such as diacetylcellulose and cellulose acetate propionate.

  The order of applying the backcoat layer may be before or after applying the actinic radiation curable resin layer of the cellulose ester film. However, when the backcoat layer also serves as an antiblocking layer, it is preferably applied first. Alternatively, the backcoat layer can be applied in two or more steps.

  The antireflection film of the present invention is also suitable for forming various functional layers by coating or plasma CVD, particularly atmospheric pressure plasma treatment, and these provide various functions to the antireflection film of the present invention. Useful to do.

  As an atmospheric pressure plasma treatment method, for example, an atmospheric pressure plasma discharge treatment method for applying a high-frequency pulse voltage described in JP-A-11-181573, JP-A-2000-26632, JP-A-2002-110397, or the like can be used. Alternatively, the conductive layer can be provided by an atmospheric pressure plasma discharge processing method described in JP-A-2001-337201. Alternatively, the antireflection layer can be provided by the methods described in JP-A No. 2002-228803, Japanese Patent Application No. 2002-369679, Japanese Patent Application No. 2002-317883, and Japanese Patent Application No. 2003-50823. Alternatively, the antifouling layer can be provided by the method described in Japanese Patent Application No. 2003-50823. Alternatively, the antireflection layer can be applied by the method described in JP-A-2003-93963 and Japanese Patent Application No. 2002-49724.

  In particular, metal oxides such as metal compounds (for example, SiOx, SiOxNy, TiOxNy, SiOxCz (x = 1 to 2, y = 0.1-1, z = 0.1-2)) under an atmosphere of nitrogen gas, Metal nitrides, metal oxynitrides, metal carbides, etc.) can be used to form thin films such as metal oxides. The nitrogen gas contained in the gas is 60 to 99.9% by volume, preferably 75 to 99.9% by volume, and more preferably 90 to 99.9% by volume. In addition to nitrogen gas, a rare gas such as argon or helium may be contained, a gas of a metal compound for forming a thin film is contained, and further a gas (addition gas) for promoting a reaction such as oxygen and hydrogen. Or an auxiliary gas). By these, a low refractive index layer, a high refractive index layer, a medium refractive index layer, a transparent conductive layer, an antistatic layer, an antifouling layer and the like containing a metal compound can be further formed.

<Antireflection layer>
The antireflection film according to the present invention has a low refractive index layer containing at least inorganic fine particles on an active ray curable resin layer, and the inorganic fine particles are provided with porous particles and a coating layer provided on the surface of the porous particles. It is characterized in that it is a composite particle or a hollow particle filled with a solvent, gas, or porous substance.

  In the present invention, the method for providing the antireflection layer is not particularly limited, but it is preferably formed by coating.

  As a method of forming the antireflection layer by coating, a method of dispersing metal oxide powder in a binder resin dissolved in a solvent, coating and drying, a method of using a polymer having a crosslinked structure as a binder resin, ethylenic unsaturated Examples of the method include a method of forming a layer by containing a monomer and a photopolymerization initiator and irradiating with actinic radiation.

  In the present invention, an antireflection layer is provided on a cellulose ester film provided with an actinic radiation curable resin layer, and at least one of the antireflection layers is a low refractive index layer.

  Although the structure of a preferable antireflection film is shown below, it is not limited to these.

  Here, the hard coat layer means the actinic radiation curable resin layer described above.

Cellulose ester film / Clear hard coat layer / Low refractive index layer Cellulose ester film / Clear hard coat layer / High refractive index layer / Low refractive index layer Cellulose ester film / Clear hard coat layer / Medium refractive index layer / High refractive index layer / Low refractive index layer Cellulose ester film / Antistatic layer / Clear hard coat layer / Low refractive index layer Cellulose ester film / Antistatic layer / Clear hard coat layer / High refractive index layer / Low refractive index layer Cellulose ester film / Antistatic layer / Clear hard coat layer / Medium refractive index layer / High refractive index layer / Low refractive index layer Cellulose ester film / Anti-glare hard coat layer / Low refractive index layer Cellulose ester film / Anti-glare hard coat layer / High refractive index layer / Low refractive index layer cellulose ester film / Anti-glare hard coat layer / Medium refractive index layer / High refractive index layer / low refractive index layer Cellulose ester film / antistatic layer / antiglare hard coat layer / low refractive index layer Cellulose ester film / antistatic layer / antiglare hard coat layer / high refractive index layer / low refractive index Index layer Cellulose ester film / Antistatic layer / Anti-glare hard coat layer / Medium refractive index layer / High refractive index layer / Low refractive index layer All are on the opposite side of the cellulose ester film coated with the hard coat layer. The above-described back coat layer is preferably provided.

  In the antireflection film, a low refractive index layer is formed as the uppermost layer, a metal oxide layer of a high refractive index layer is formed between the active ray curable resin layer, and an active ray curable resin layer and a high refractive index. Providing a medium refractive index layer (a metal oxide content or a ratio with a resin binder, a metal oxide layer in which the refractive index is adjusted by changing the type of metal) between the two layers reduces the reflectance. Therefore, it is preferable. The refractive index of the high refractive index layer is preferably 1.55 to 2.30, and more preferably 1.57 to 2.20. The refractive index of the medium refractive index layer is adjusted so as to be an intermediate value between the refractive index (about 1.5) of the cellulose ester film as the substrate and the refractive index of the high refractive index layer. The refractive index of the middle refractive index layer is preferably 1.55-1.80. The refractive index of the low refractive index layer is preferably 1.3 to 1.44, more preferably 1.20 to 1.42. The thickness of each layer is preferably 5 nm to 0.5 μm, more preferably 10 nm to 0.3 μm, and most preferably 30 nm to 0.2 μm. The haze of the metal oxide layer is preferably 5% or less, more preferably 3% or less, and most preferably 1% or less. The strength of the metal oxide layer is preferably 3H or more, and most preferably 4H or more, with a pencil hardness of 1 kg. When the metal oxide layer is formed by coating, it is preferable to include inorganic fine particles and a binder polymer.

  Moreover, it is preferable to add a slipping agent to the low refractive index layer or other refractive index layers of the present invention, and scratch resistance can be improved by imparting slipperiness. As the slip agent, silicon oil or a wax-like substance is preferably used. For example, a compound represented by the following general formula is preferable.

General formula R ₁ COR ₂
In the formula, R ₁ represents a saturated or unsaturated aliphatic hydrocarbon group having 12 or more carbon atoms. An alkyl group or an alkenyl group is preferable, and an alkyl group or alkenyl group having 16 or more carbon atoms is more preferable. R ₂ represents —OM ₁ group (M ₁ represents an alkali metal such as Na or K), —OH group, —NH ₂ group, or —OR ₃ group (R ₃ represents a saturated or unsaturated group having 12 or more carbon atoms. R ₂ represents a saturated aliphatic hydrocarbon group, preferably an alkyl group or an alkenyl group, and R ₂ is preferably an —OH group, —NH ₂ group, or —OR ₃ group. Specifically, higher fatty acids such as behenic acid, stearamide, and pentacoic acid, or derivatives thereof, and carnauba wax, beeswax, and montan wax containing many of these components as natural products can also be preferably used. Polyorganosiloxane as disclosed in JP-B-53-292, higher fatty acid amide as disclosed in US Pat. No. 4,275,146, JP-B 58-33541, British patent No. 927,446 or JP-A-55-126238 and 58-90633, higher fatty acid esters (fatty acids having 10 to 24 carbon atoms and 10 to 24 carbon atoms). Esters of alcohols), and higher fatty acid metal salts as disclosed in U.S. Pat. No. 3,933,516, dicarboxylic acids having up to 10 carbon atoms as disclosed in JP-A-51-37217 A polyester compound comprising an acid and an aliphatic or cycloaliphatic diol, a dicarboxylic acid disclosed in JP-A-7-13292, It can be mentioned oligo polyester or the like from the Le.

For example, the amount of slip agent to be used in the low refractive index layer is preferably ^{0.01mg / m 2 ~10mg / m 2} .

  In the present invention, in order to reduce the reflectance, it is also preferable to provide a high refractive index layer between the transparent support provided with the active ray curable resin layer and the low refractive index layer. In addition, it is more preferable to provide a middle refractive index layer between the transparent support and the high refractive index layer in order to reduce the reflectance. The refractive index of the high refractive index layer is preferably 1.55 to 2.30, and more preferably 1.57 to 2.20. The refractive index of the medium refractive index layer is adjusted to be an intermediate value between the refractive index of the transparent support and the refractive index of the high refractive index layer. The refractive index of the middle refractive index layer is preferably 1.55-1.80. The thickness of the high refractive index layer and the medium refractive index layer is preferably 5 nm to 1 μm, more preferably 10 nm to 0.2 μm, and most preferably 30 nm to 0.1 μm. The haze of the high refractive index layer and the medium refractive index layer is preferably 5% or less, more preferably 3% or less, and most preferably 1% or less. The strength of the high refractive index layer and the medium refractive index layer is preferably H or higher, more preferably 2H or higher, and most preferably 3H or higher, with a pencil hardness of 1 kg.

  Among the refractive index layers used in the present invention, the high refractive index layer was formed by applying and drying a coating solution containing a monomer, oligomer or hydrolyzate of an organic titanium compound represented by the following general formula. A layer of 55 to 2.5 is preferred.

General formula Ti (OR ₁ ) ₄
In the formula, R ₁ is preferably an aliphatic hydrocarbon group having 1 to 8 carbon atoms, preferably an aliphatic hydrocarbon group having 1 to 4 carbon atoms. Moreover, the monomer, oligomer, or hydrolyzate thereof of an organic titanium compound reacts like -Ti-O-Ti- when an alkoxide group is hydrolyzed to form a crosslinked structure, thereby forming a cured layer.

Examples of the monomer or oligomer of the organic titanium compound used in the present invention include Ti (OCH ₃ ) ₄ , Ti (OC ₂ H ₅ ) ₄ , Ti (On-C ₃ H ₇ ) ₄ , Ti (O-i- _{C 3 H 7) 4, Ti} (O-n-C4H9) 4, Ti (O-n-C 3 H 7) 4 2-10 mer, Ti (O-i-C 3 H 7) 4 2 10-mer, 2-10 mers etc. _{Ti (O-n-C 4} H 9) 4 are preferred examples. These may be used alone or in combination of two or more. Of these _{Ti (O-n-C 3} H 7) 4, Ti (O-i-C 3 H 7) 4, Ti (O-n-C 4 H 9) 4, Ti (O-n-C 3 H 7 ) ₄ to 10-mer and Ti (On-C ₄ H ₉ ) ₄ to 10-mer are particularly preferable.

  Among the coating solutions for the high refractive index layer used in the present invention, it is preferable to add the organic titanium compound to a solution in which water and an organic solvent described later are sequentially added. When water is added later, hydrolysis / polymerization does not proceed uniformly, and white turbidity occurs or film strength decreases. After the water and the organic solvent are added, it is preferable that they are stirred and mixed and dissolved in order to mix well.

  Further, as another method, it is also a preferred embodiment that an organic titanium compound and an organic solvent are mixed and this mixed solution is added to the mixed and stirred solution of water and the organic solvent.

Moreover, it is preferable that the quantity of water is the range of 0.25-3 mol with respect to 1 mol of organic titanium compounds. When the amount is less than 0.25 mol, hydrolysis and polymerization are not sufficiently progressed and the film strength is lowered. If it exceeds 3 moles, hydrolysis and polymerization will proceed excessively, resulting in generation of coarse TiO ₂ particles and white turbidity. Therefore, the amount of water needs to be adjusted within the above range.

  Moreover, it is preferable that the content rate of water is less than 10 mass% with respect to the coating liquid total amount. If the water content is 10% by mass or more with respect to the total amount of the coating solution, it is not preferable because the stability of the coating solution with time deteriorates and white turbidity occurs.

  The organic solvent used in the present invention is preferably a water-miscible organic solvent. Examples of the water-miscible organic solvent include alcohols (eg, methanol, ethanol, propanol, isopropanol, butanol, isobutanol, secondary butanol, tertiary butanol, pentanol, hexanol, cyclohexanol, benzyl alcohol, etc.), many Monohydric alcohols (for example, ethylene glycol, diethylene glycol, triethylene glycol, polyethylene glycol, propylene glycol, dipropylene glycol, polypropylene glycol, butylene glycol, hexanediol, pentanediol, glycerin, hexanetriol, thiodiglycol, etc.), polyvalent Alcohol ethers (eg, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether) , Ethylene glycol monobutyl ether, diethylene glycol monomethyl ether, diethylene glycol monomethyl ether, diethylene glycol monobutyl ether, propylene glycol monomethyl ether, propylene glycol monobutyl ether, ethylene glycol monomethyl ether acetate, triethylene glycol monomethyl ether, triethylene glycol monoethyl ether, ethylene glycol mono Phenyl ether, propylene glycol monophenyl ether, etc.), amines (eg, ethanolamine, diethanolamine, triethanolamine, N-methyldiethanolamine, N-ethyldiethanolamine, morpholine, N-ethylmorpholine, ethylenediamine, diethylenediamine) , Triethylenetetramine, tetraethylenepentamine, polyethyleneimine, pentamethyldiethylenetriamine, tetramethylpropylenediamine, etc.), amides (eg, formamide, N, N-dimethylformamide, N, N-dimethylacetamide, etc.), heterocyclic rings (For example, 2-pyrrolidone, N-methyl-2-pyrrolidone, cyclohexyl pyrrolidone, 2-oxazolidone, 1,3-dimethyl-2-imidazolidinone, etc.), sulfoxides (for example, dimethyl sulfoxide, etc.), sulfones (for example, , Sulfolane and the like), urea, acetonitrile, acetone and the like, and alcohols, polyhydric alcohols, and polyhydric alcohol ethers are particularly preferable. The amount of these organic solvents used may be adjusted as described above so that the water content is less than 10% by mass with respect to the total amount of the coating solution.

  The monomer, oligomer or hydrolyzate of the organic titanium compound used in the present invention preferably occupies 50.0% by mass to 98.0% by mass in the solid content contained in the coating solution. The solid content ratio is more preferably 50% by mass to 90% by mass, and further preferably 55% by mass to 90% by mass. In addition, it is also preferable to add to the coating composition a polymer of an organic titanium compound (a product obtained by crosslinking the organic titanium compound in advance by hydrolysis) or titanium oxide fine particles.

  The high refractive index layer and medium refractive index layer used in the present invention preferably include those containing metal oxide particles as fine particles and further containing a binder polymer.

  Alternatively, when the organic titanium compound hydrolyzed / polymerized by the coating liquid preparation method and the metal oxide particles are combined, the metal oxide particles and the hydrolyzed / polymerized organic titanium compound are firmly bonded, and the hardness of the particles A strong coating film having the flexibility of a uniform film can be obtained.

The metal oxide particles used for the high refractive index layer and the medium refractive index layer preferably have a refractive index of 1.80 to 2.80, and more preferably 1.90 to 2.80. The weight average diameter of the primary particles of the metal oxide particles is preferably 1 to 150 nm, more preferably 1 to 100 nm, and most preferably 1 to 80 nm. The weight average diameter of the metal oxide particles in the layer is preferably 1 to 200 nm, more preferably 5 to 150 nm, still more preferably 10 to 100 nm, and more preferably 10 to 80 nm. Most preferred. The average particle diameter of the metal oxide particles is measured by a light scattering method if it is 20-30 nm or more, and by an electron micrograph if it is 20-30 nm or less. The specific surface area of metal oxide particles, as measured values by the BET method is preferably from 10 to 400 m ² / g, more preferably from 20 to 200 m ² / g, with 30 to 150 m ² / g Most preferably it is.

  Examples of the metal oxide particles include at least one selected from Ti, Zr, Sn, Sb, Cu, Fe, Mn, Pb, Cd, As, Cr, Hg, Zn, Al, Mg, Si, P, and S. Specific examples of the metal oxide include titanium dioxide (eg, rutile, rutile / anatase mixed crystal, anatase, amorphous structure), tin oxide, indium oxide, zinc oxide, and zirconium oxide. Of these, titanium oxide, tin oxide, and indium oxide are particularly preferable. The metal oxide particles are mainly composed of oxides of these metals, can further contain other elements, and fine particles imparted with conductivity are also preferably used. The main component means a component having the largest content (mass%) among the components constituting the particles. Examples of other elements include Ti, Zr, Sn, Sb, Cu, Fe, Mn, Pb, Cd, As, Cr, Hg, Zn, Al, Mg, Si, P, and S.

  The metal oxide particles are preferably surface-treated. The surface treatment can be performed using an inorganic compound or an organic compound. Examples of inorganic compounds used for the surface treatment include alumina, silica, zirconium oxide and iron oxide. Of these, alumina and silica are preferable. Examples of the organic compound used for the surface treatment include polyols, alkanolamines, stearic acid, silane coupling agents, and titanate coupling agents. Of these, a silane coupling agent is most preferable.

  Specific examples of the silane coupling agent include methyltrimethoxysilane, methyltriethoxysilane, methyltrimethoxyethoxysilane, methyltriacetoxysilane, methyltributoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, vinyltriethoxysilane. Methoxysilane, vinyltriethoxysilane, vinyltriacetoxysilane, vinyltrimethoxyethoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane, phenyltriacetoxysilane, γ-chloropropyltrimethoxysilane, γ-chloropropyltriethoxysilane, γ-chloropropyltriacetoxysilane, 3,3,3-trifluoropropyltrimethoxysilane, γ-glycidyloxypropyltrimethoxysilane, γ-glycidyloxy Propyltriethoxysilane, γ- (β-glycidyloxyethoxy) propyltrimethoxysilane, β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, β- (3,4-epoxycyclohexyl) ethyltriethoxysilane, γ-acryloyloxypropyltrimethoxysilane, γ-methacryloyloxypropyltrimethoxysilane, γ-aminopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, γ-mercaptopropyltrimethoxysilane, γ-mercaptopropyltriethoxysilane, Examples include N-β- (aminoethyl) -γ-aminopropyltrimethoxysilane and β-cyanoethyltriethoxysilane.

  Examples of silane coupling agents having a disubstituted alkyl group with respect to silicon include dimethyldimethoxysilane, phenylmethyldimethoxysilane, dimethyldiethoxysilane, phenylmethyldiethoxysilane, and γ-glycidyloxypropylmethyldiethoxysilane. Γ-glycidyloxypropylmethyldimethoxysilane, γ-glycidyloxypropylphenyldiethoxysilane, γ-chloropropylmethyldiethoxysilane, dimethyldiacetoxysilane, γ-acryloyloxypropylmethyldimethoxysilane, γ-acryloyloxypropylmethyldi Ethoxysilane, γ-methacryloyloxypropylmethyldimethoxysilane, γ-methacryloyloxypropylmethyldiethoxysilane, γ-mercaptopropylmethyldimeth Shishiran, .gamma.-mercaptopropyl methyl diethoxy silane, .gamma.-aminopropyl methyl dimethoxy silane, .gamma.-aminopropyl methyl diethoxy silane, methyl vinyl dimethoxy silane, and methyl vinyl diethoxy silane.

  Among these, vinyltrimethoxysilane, vinyltriethoxysilane, vinyltriacetoxysilane, vinyltrimethoxyethoxysilane, γ-acryloyloxypropyltrimethoxysilane and γ-methacryloyloxypropyltrimethoxysilane having a double bond in the molecule. Γ-acryloyloxypropylmethyldimethoxysilane, γ-acryloyloxypropylmethyldiethoxysilane, γ-methacryloyloxypropylmethyldimethoxysilane, and γ-methacryloyloxypropylmethyldiethoxy having a disubstituted alkyl group with respect to silicon Silane, methylvinyldimethoxysilane and methylvinyldiethoxysilane are preferred, and γ-acryloyloxypropyltrimethoxysilane and γ-methacryloyloxyp Particularly preferred are propyltrimethoxysilane, γ-acryloyloxypropylmethyldimethoxysilane, γ-acryloyloxypropylmethyldiethoxysilane, γ-methacryloyloxypropylmethyldimethoxysilane and γ-methacryloyloxypropylmethyldiethoxysilane.

  Two or more coupling agents may be used in combination. In addition to the silane coupling agents shown above, other silane coupling agents may be used. Other silane coupling agents include alkyl esters of orthosilicate (eg, methyl orthosilicate, ethyl orthosilicate, n-propyl orthosilicate, i-propyl orthosilicate, n-butyl orthosilicate, sec-butyl orthosilicate, orthosilicate). Acid t-butyl) and its hydrolyzate.

  The surface treatment with the coupling agent can be carried out by adding the coupling agent to the fine particle dispersion and allowing the dispersion to stand at a temperature from room temperature to 60 ° C. for several hours to 10 days. In order to accelerate the surface treatment reaction, inorganic acids (for example, sulfuric acid, hydrochloric acid, nitric acid, chromic acid, hypochlorous acid, boric acid, orthosilicic acid, phosphoric acid, carbonic acid), organic acids (for example, acetic acid, polyacrylic acid, Benzenesulfonic acid, phenol, polyglutamic acid), or salts thereof (eg, metal salts, ammonium salts) may be added to the dispersion.

  These silane coupling agents are preferably hydrolyzed with a necessary amount of water in advance. When the silane coupling agent is hydrolyzed, the surfaces of the organic titanium compound and the metal oxide particles described above are easy to react and a stronger film is formed. It is also preferable to add a hydrolyzed silane coupling agent to the coating solution in advance. The water used for this hydrolysis can also be used for the hydrolysis / polymerization of the organic titanium compound.

  In the present invention, the treatment may be performed by combining two or more kinds of surface treatments. The shape of the metal oxide particles is preferably a rice grain shape, a spherical shape, a cubic shape, a spindle shape or an indefinite shape. Two or more kinds of metal oxide particles may be used in the high refractive index layer or the middle refractive index layer.

  The ratio of the metal oxide particles in the high refractive index layer and the medium refractive index layer is preferably 5 to 65% by volume, more preferably 10 to 60% by volume, and still more preferably 20 to 55% by volume. is there.

  The metal oxide particles are supplied to a coating solution for forming a high refractive index layer and a medium refractive index layer in a dispersion state dispersed in a medium. As a dispersion medium for metal oxide particles, it is preferable to use a liquid having a boiling point of 60 to 170 ° C. Specific examples of the dispersion solvent include water, alcohol (eg, methanol, ethanol, isopropanol, butanol, benzyl alcohol), ketone (eg, acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone), ketone alcohol (eg, diacetone alcohol). , Esters (eg, methyl acetate, ethyl acetate, propyl acetate, butyl acetate, methyl formate, ethyl formate, propyl formate, butyl formate), aliphatic hydrocarbons (eg, hexane, cyclohexane), halogenated hydrocarbons (eg, methylene) Chloride, chloroform, carbon tetrachloride), aromatic hydrocarbons (eg, benzene, toluene, xylene), amides (eg, dimethylformamide, dimethylacetamide, n-methylpyrrolidone), ethers (eg, diethyl ether, dioxane, Tiger hydrofuran), ether alcohols (e.g., 1-methoxy-2-propanol). Of these, toluene, xylene, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone and butanol are particularly preferable.

  The metal oxide particles can be dispersed in the medium using a disperser. Examples of the disperser include a sand grinder mill (eg, a bead mill with pins), a high-speed impeller mill, a pebble mill, a roller mill, an attritor, and a colloid mill. A sand grinder mill and a high-speed impeller mill are particularly preferred. Further, preliminary dispersion processing may be performed. Examples of the disperser used for the preliminary dispersion treatment include a ball mill, a three-roll mill, a kneader, and an extruder.

  The high refractive index layer and medium refractive index layer used in the present invention preferably use a polymer having a crosslinked structure (hereinafter also referred to as a crosslinked polymer) as a binder polymer. Examples of the crosslinked polymer include polymers having a saturated hydrocarbon chain such as polyolefin (hereinafter collectively referred to as polyolefin), and crosslinked products such as polyether, polyurea, polyurethane, polyester, polyamine, polyamide, and melamine resin. Among them, a crosslinked product of polyolefin, polyether and polyurethane is preferred, a crosslinked product of polyolefin and polyether is more preferred, and a crosslinked product of polyolefin is most preferred. Further, it is further preferable that the crosslinked polymer has an anionic group. The anionic group has a function of maintaining the dispersion state of the inorganic fine particles, and the crosslinked structure has a function of imparting a film forming ability to the polymer and strengthening the film. The anionic group may be directly bonded to the polymer chain or may be bonded to the polymer chain via a linking group, but is bonded to the main chain as a side chain via the linking group. Is preferred.

  Examples of the anionic group include a carboxylic acid group (carboxyl), a sulfonic acid group (sulfo), and a phosphoric acid group (phosphono). Of these, sulfonic acid groups and phosphoric acid groups are preferred. Here, the anionic group may be in a salt state. The cation that forms a salt with the anionic group is preferably an alkali metal ion. Moreover, the proton of the anionic group may be dissociated. The linking group that binds the anionic group and the polymer chain is preferably a divalent group selected from —CO—, —O—, an alkylene group, an arylene group, and combinations thereof. The crosslinked polymer which is a preferable binder polymer is preferably a copolymer having a repeating unit having an anionic group and a repeating unit having a crosslinked structure. In this case, the ratio of the repeating unit having an anionic group in the copolymer is preferably 2 to 96% by mass, more preferably 4 to 94% by mass, and most preferably 6 to 92% by mass. preferable. The repeating unit may have two or more anionic groups.

  The crosslinked polymer having an anionic group may contain other repeating units (a repeating unit having neither an anionic group nor a crosslinked structure). Other repeating units are preferably a repeating unit having an amino group or a quaternary ammonium group and a repeating unit having a benzene ring. The amino group or quaternary ammonium group has a function of maintaining the dispersed state of the inorganic fine particles, like the anionic group. The benzene ring has a function of increasing the refractive index of the high refractive index layer. The amino group, the quaternary ammonium group, and the benzene ring can obtain the same effect even if they are contained in a repeating unit having an anionic group or a repeating unit having a crosslinked structure.

  In the crosslinked polymer containing a repeating unit having an amino group or a quaternary ammonium group as a constituent unit, the amino group or quaternary ammonium group may be directly bonded to the polymer chain, or may be a side chain via a linking group. May be bonded to the polymer chain, but the latter is more preferred. The amino group or quaternary ammonium group is preferably a secondary amino group, a tertiary amino group or a quaternary ammonium group, more preferably a tertiary amino group or a quaternary ammonium group. The group bonded to the nitrogen atom of the secondary amino group, tertiary amino group or quaternary ammonium group is preferably an alkyl group, more preferably an alkyl group having 1 to 12 carbon atoms, still more preferably carbon number. 1 to 6 alkyl groups. The counter ion of the quaternary ammonium group is preferably a halide ion. The linking group that connects the amino group or quaternary ammonium group to the polymer chain is a divalent group selected from —CO—, —NH—, —O—, an alkylene group, an arylene group, and combinations thereof. Is preferred. When the crosslinked polymer includes a repeating unit having an amino group or a quaternary ammonium group, the ratio is preferably 0.06 to 32% by mass, more preferably 0.08 to 30% by mass, Most preferably, it is 0.1-28 mass%.

  The cross-linked polymer is prepared by blending a monomer for generating a cross-linked polymer to prepare a coating solution for forming a high refractive index layer and a medium refractive index layer, and is generated by a polymerization reaction simultaneously with or after coating of the coating solution. Is preferred. Each layer is formed with the production of the crosslinked polymer. The monomer having an anionic group functions as a dispersant for inorganic fine particles in the coating solution. The monomer having an anionic group is preferably used in an amount of 1 to 50% by mass, more preferably 5 to 40% by mass, and still more preferably 10 to 30% by mass with respect to the inorganic fine particles. The monomer having an amino group or a quaternary ammonium group functions as a dispersion aid in the coating solution. The monomer having an amino group or a quaternary ammonium group is preferably used in an amount of 3 to 33% by mass based on the monomer having an anionic group. These monomers can be made to function effectively before application of the coating liquid by a method of forming a crosslinked polymer by a polymerization reaction simultaneously with or after application of the coating liquid.

  As the monomer used in the present invention, a monomer having two or more ethylenically unsaturated groups is most preferable, and examples thereof include esters of polyhydric alcohol and (meth) acrylic acid (eg, ethylene glycol di ( (Meth) acrylate, 1,4-dichlorohexanediacrylate, pentaerythritol tetra (meth) acrylate, pentaerythritol tri (meth) acrylate, trimethylolpropane tri (meth) acrylate, trimethylolethane tri (meth) acrylate, dipentaerythritol Tetra (meth) acrylate, dipentaerythritol penta (meth) acrylate, pentaerythritol hexa (meth) acrylate, 1,2,3-cyclohexanetetramethacrylate, polyurethane polyacrylate, polyester Terpolyacrylate), vinylbenzene and its derivatives (eg, 1,4-divinylbenzene, 4-vinylbenzoic acid-2-acryloylethyl ester, 1,4-divinylcyclohexanone), vinylsulfone (eg, divinylsulfone), acrylamide (E.g., methylenebisacrylamide) and methacrylamide. Commercially available monomers may be used as the monomer having an anionic group and the monomer having an amino group or a quaternary ammonium group. As a commercially available monomer having a commercially available anionic group, KAYAMAPMPM-21, PM-2 (manufactured by Nippon Kayaku Co., Ltd.), Antox MS-60, MS-2N, MS-NH4 (manufactured by Nippon Emulsifier Co., Ltd.) , Aronix M-5000, M-6000, M-8000 series (manufactured by Toagosei Chemical Industry Co., Ltd.), Biscote # 2000 series (manufactured by Osaka Organic Chemical Industry Co., Ltd.), New Frontier GX-8289 (Daiichi Kogyo Seiyaku) NK ester CB-1, A-SA (manufactured by Shin-Nakamura Chemical Co., Ltd.), AR-100, MR-100, MR-200 (manufactured by Eighth Chemical Industry Co., Ltd.), and the like. It is done. Examples of commercially available monomers having a commercially available amino group or quaternary ammonium group include DMAA (manufactured by Osaka Organic Chemical Industry Co., Ltd.), DMAEA, DMAPAA (manufactured by Kojin Co., Ltd.), and Bremer QA (Nippon Yushi Co., Ltd.). ) And New Frontier C-1615 (Daiichi Kogyo Seiyaku Co., Ltd.).

  For the polymerization reaction of the polymer, a photopolymerization reaction or a thermal polymerization reaction can be used. A photopolymerization reaction is particularly preferable. A polymerization initiator is preferably used for the polymerization reaction. For example, the thermal polymerization initiator mentioned later used in order to form the binder polymer of a hard-coat layer, and a photoinitiator are mentioned.

  A commercially available polymerization initiator may be used as the polymerization initiator. In addition to the polymerization initiator, a polymerization accelerator may be used. The addition amount of the polymerization initiator and the polymerization accelerator is preferably in the range of 0.2 to 10% by mass of the total amount of monomers. The coating liquid (dispersion of inorganic fine particles containing monomer) may be heated to promote polymerization of the monomer (or oligomer). Moreover, it may heat after the photopolymerization reaction after application | coating, and may additionally process the thermosetting reaction of the formed polymer.

  For the medium refractive index layer and the high refractive index layer, it is preferable to use a polymer having a relatively high refractive index. Examples of the polymer having a high refractive index include polystyrene, styrene copolymer, polycarbonate, melamine resin, phenol resin, epoxy resin, and polyurethane obtained by reaction of cyclic (alicyclic or aromatic) isocyanate and polyol. . Polymers having other cyclic (aromatic, heterocyclic, alicyclic) groups and polymers having halogen atoms other than fluorine as substituents can also be used with a high refractive index.

  In addition, when the antireflection film according to the present invention has a high refractive index layer and a low refractive index layer according to the present invention thereon, the intermediate refractive index layer and the high refractive index layer are further interposed. In the case of having a low refractive index layer according to the present invention on the layer, the layer in contact with the low refractive index layer according to the present invention is a nonionic surfactant, and is represented by (C) in the present invention. It is preferable from the viewpoint of occurrence of unevenness that a nonionic surfactant having a hydrophobic group composed of dimethylpolysiloxane and a hydrophilic group composed of polyoxyalkylene is contained in a layer in contact with the low refractive index layer. A preferable addition amount is preferably 0.001 to 5 parts by mass with respect to the coating composition (solid content), and a particularly preferable blending ratio is 0.003 to 3 parts by mass.

  Each layer of the antireflection layer can be formed by coating by a dip coating method, an air knife coating method, a curtain coating method, a roller coating method, a wire bar coating method, a gravure coating method, a micro gravure coating method or an extrusion coating method. I can do it.

<Polarizer>
The polarizing plate of the present invention will be described.

  The polarizing plate can be produced by a general method. The back surface side of the antireflection film of the present invention is subjected to alkali saponification treatment, and a completely saponified polyvinyl alcohol aqueous solution is used on at least one surface of a polarizing film prepared by immersing and stretching the treated antireflection film in an iodine solution. It is preferable to bond them together. The antireflection film may be used on the other surface, or another polarizing plate protective film may be used. With respect to the antireflection film of the present invention, the polarizing plate protective film used on the other surface has an in-plane retardation Ro of 590 nm, a phase difference of 20 to 70 nm, and Rt of 100 to 400 nm. preferable. These can be created, for example, by the method described in JP-A-2002-71957 and Japanese Patent Application No. 2002-155395. Alternatively, it is preferable to use a polarizing plate protective film that also serves as an optical compensation film having an optically anisotropic layer formed by aligning a liquid crystal compound such as a discotic liquid crystal. For example, the optically anisotropic layer can be formed by the method described in JP-A-2003-98348. By using it in combination with the antireflection film of the present invention, a polarizing plate having excellent flatness and a stable viewing angle expansion effect can be obtained.

  As the polarizing plate protective film used on the back side, KC8UX2MW, KC4UX, KC5UX, KC4UY, KC8UY, KC12UR, KC8UCR-3 (manufactured by Konica Minolta Opto Co., Ltd.) and the like are preferably used as commercially available cellulose ester films.

  The polarizing film, which is the main component of the polarizing plate, is an element that transmits only light having a polarization plane in a certain direction. A typical polarizing film known at present is a polyvinyl alcohol polarizing film, which is a polyvinyl alcohol film. There are one in which iodine is dyed on a system film and one in which dichroic dye is dyed. As the polarizing film, a polyvinyl alcohol aqueous solution is formed and dyed by uniaxially stretching or dyed, or uniaxially stretched after dyeing, and then preferably subjected to a durability treatment with a boron compound. On the surface of the polarizing film, one side of the antireflection film of the present invention is bonded to form a polarizing plate. It is preferably bonded with an aqueous adhesive mainly composed of completely saponified polyvinyl alcohol or the like.

  A conventional polarizing plate using an antireflection film is inferior in flatness, and when a reflection image is seen, fine wavy irregularities are recognized, pencil hardness is only about 2H, and durability under conditions of 60 ° C. and 90% RH. As a result of the property test, the wavy unevenness increased. On the other hand, the polarizing plate using the antireflection film of the present invention was excellent in antireflection performance, excellent in flatness, and excellent in pencil hardness. In addition, even in a durability test under the conditions of 60 ° C. and 90% RH, the wavy unevenness does not increase, and even with a polarizing plate having an optical compensation film on the back surface side, the viewing angle characteristics after the durability test are It was possible to provide good viewing angle characteristics without fluctuation.

<Display device>
By incorporating the polarizing plate of the present invention into a display device, the display device of the present invention having various visibility can be manufactured. The antireflection film of the present invention is a reflection type, transmission type, transflective type LCD or LCD of various drive systems such as TN type, STN type, OCB type, HAN type, VA type (PVA type, MVA type), IPS type, etc. Preferably used. In addition, the antireflection film of the present invention has significantly less uneven color of the reflected light of the antireflection layer, low reflectance, excellent flatness, plasma display, field emission display, organic EL display, inorganic EL display, electronic It is also preferably used for various display devices such as paper. In particular, a large-screen display device with a 30-inch screen or more has the effect that there is little color unevenness and wavy unevenness, and eyes are not tired even during long-time viewing.

  EXAMPLES Hereinafter, although this invention is demonstrated concretely using an Example, this invention is not limited to these aspects.

Example 1
[Production of cellulose ester film]
A cellulose ester solution (dope) was prepared using the following cellulose ester, plasticizer, ultraviolet absorber, fine particles, and solvent, and a cellulose ester film was prepared by a solution casting film forming method.
Cellulose ester;
Cellulose triacetate 100kg
(Acetyl group substitution degree 2.9 Mn = 16000 Mw / Mn = 1.8)
Plasticizers;
Trimethylolpropane tribenzoate 5kg
Ethyl phthalyl ethyl glycolate 5kg
UV absorbers;
Tinuvin 109 (Ciba Specialty Chemicals Co., Ltd.) 1.0kg
Tinuvin 171 (Ciba Specialty Chemicals Co., Ltd.) 1.0kg
Fine particles;
Aerosil R972V (Nippon Aerosil Co., Ltd.) 0.3kg
solvent;
440 kg of methyl acetate
110 kg of ethanol
A cellulose ester solution (dope) was prepared using the above cellulose ester, plasticizer, ultraviolet absorber, fine particles, and solvent.

  That is, the solvent was put into an airtight container, the remaining materials were put in order with stirring, and completely dissolved and mixed while heating and stirring. The fine particles were added dispersed in a part of the solvent. After the temperature was lowered to the temperature at which the solution was cast and allowed to stand overnight, a defoaming operation was performed, and then the solution was produced by Azumi Filter Paper No. Filtration using 244 gave a cellulose ester solution.

  Next, the cellulose ester solution whose temperature was adjusted to 33 ° C. was fed to a die and uniformly cast from a die slit onto a stainless steel belt. The cast part of the stainless steel belt was heated from the back with hot water of 37 ° C. After casting, the dope film on the metal support (referred to as a web after casting on a stainless steel belt) is dried by applying hot air of 44 ° C., and the residual solvent in the peeling is peeled off at 120% by mass. Then, the web was stretched so that the longitudinal stretching ratio was 1.1 times, and then the web edge was gripped with a tenter while the residual solvent amount was from 35% by mass to 10% by mass. It extended | stretched so that it might become 1.1 times the draw ratio. After stretching, the width is maintained for several seconds, then the tension in the width direction is relaxed, then the width is released, and further transported for 20 minutes in the third drying zone set at 125 ° C. for drying. Then, a cellulose ester film having a width of 1.4 to 2 m and a film thickness of 50 μm was produced.

[Coating of actinic radiation curable resin layer]
<< Hard coat film H1 >>
On the surface of the cellulose ester film (B surface side; the surface in contact with the support mirror surface such as a stainless steel band used in the casting film forming method; support side), the following coating solution for actinic radiation curable resin layer has a pore size of 0. An actinic radiation curable resin layer coating solution 1 is prepared by filtration through a 4 μm polypropylene filter, which is applied using a micro gravure coater, dried at 90 ° C., and then irradiated with an ultraviolet lamp having an illuminance of 100 mW / in cm ^2, thereby curing the coated layer to the radiation dose as 80 mJ / cm ^2, to prepare a hard coat film H1 form an active ray curable resin layer having a thickness of 5 [mu] m. The refractive index of the actinic radiation curable resin layer was 1.5.

<Coating liquid 1 for active ray curable resin layer>
Dipentaerythritol hexaacrylate 70 parts by mass Dipentaerythritol pentaacrylate 30 parts by mass Photoinitiator 5 parts by mass (Irgacure 184 (manufactured by Ciba Specialty Chemicals))
Ethyl acetate 120 parts by mass Propylene glycol monomethyl ether 120 parts by mass Silicon compound 0.4 parts by mass (BYK-307 (produced by Big Chemie Japan))
FZ2207 (manufactured by Nippon Unicar Co., Ltd.) 0.2 parts by mass << hard coat film H2 >>
On the cellulose ester film, the actinic radiation curable resin layer H2 is similarly coated using the following actinic radiation curable resin layer coating liquid 2 instead of the actinic radiation curable resin layer coating liquid 1, and the hard coat film H2 is coated. Produced.

<Coating liquid 2 for active ray curable resin layer>
A solution obtained by dispersing fine particles of zirconium oxide having a particle diameter of about 10 nm in a solvent is added to the coating solution 1 for actinic radiation curable resin layer, and adjusted so that the refractive index of the actinic radiation curable resin layer is 1.61. It was set as the coating liquid 2 for wire-curing resin layers.

<< Hard coat film H3 >>
An active ray curable resin layer (lower layer) having a thickness of 4.5 μm is formed on the cellulose ester film using the active ray curable resin layer coating solution 1 in the same manner as the hard coat film H1, and then the following activity is further achieved. An upper layer having a thickness of 1.5 μm was applied and formed using the coating solution 3 for a line curable resin layer, to produce a hard coat film H3.

<Coating liquid 3 for active ray curable resin layer>
Antimony oxide (Sb ₂ O ₅ ) fine particles (Nippon Seiko Co., Ltd.) having an average particle size of about 0.03 μm so that the refractive index of the active ray curable resin layer is 1.61. )) Was dispersed in a solvent (as Sb ₂ O ₅ , 28% by mass with respect to the solid content of the coating solution) to obtain a coating solution 2 for active ray curable resin layer.

<< Hard Coat Film H4 >>
A hard coat film H4 was similarly produced on the cellulose ester film using the following actinic radiation curable resin layer coating solution 4 instead of the actinic radiation curable resin layer coating solution 1.

<Coating liquid 4 for active ray curable resin layer>
Dipentaerythritol hexaacrylate 70 parts by mass Dipentaerythritol pentaacrylate 30 parts by mass Photoinitiator 5 parts by mass (Irgacure 184 (manufactured by Ciba Specialty Chemicals))
Ethyl acetate 120 parts by mass Propylene glycol monomethyl ether 120 parts by mass Silicon compound 0.4 parts by mass (BYK-307 (produced by Big Chemie Japan))
[Coating of back coat layer]
Furthermore, the following coating composition for a back coat layer was prepared by filtering with a filter having a particle capture efficiency of 3 μm of 99% or more and 0.5 μm or less and a particle capture efficiency of 10% or less. The backcoat layer coating composition is a film coated with the above-mentioned hardcoat layer, on the surface opposite to the surface coated with the hardcoat layer, so that the wet film thickness is 15 μm using an extrusion coater. It was applied and dried at 90 ° C. for 30 seconds.

<Coating liquid for back coat layer>
Diacetylcellulose (acetyl group substitution degree 2.4) 0.5 parts by mass Acetone 70 parts by mass Methanol 20 parts by mass Propylene glycol monomethyl ether 10 parts by mass Ultrafine silica Aerosil 200V (manufactured by Nippon Aerosil Co., Ltd.) 0.002 parts by mass or more In this manner, hard coat films H1 to H4 with a back coat layer were produced.

(Production of low refractive index layer)
Next, composite particles and silica-based fine particles (cavity particles) were prepared.

(Preparation of silica-based fine particles P-2)
A mixture of 100 g of silica sol having an average particle diameter of 5 nm and a SiO ₂ concentration of 20% by mass and 1900 g of pure water was heated to 80 ° C. The pH of this reaction mother liquor was 10.5, and 9000 g of 0.98 mass% sodium silicate aqueous solution as SiO ₂ and 9000 g of 1.02 mass% sodium aluminate aqueous solution as Al ₂ O ₃ were simultaneously added to the mother liquor. did. Meanwhile, the temperature of the reaction solution was kept at 80 ° C. The pH of the reaction solution rose to 12.5 immediately after the addition, and hardly changed thereafter. After completion of the addition, the reaction solution was cooled to room temperature and washed with an ultrafiltration membrane to prepare a SiO ₂ .Al ₂ O ₃ core particle dispersion having a solid content concentration of 20% by mass. (Process (a))
1700 g of pure water is added to 500 g of this core particle dispersion and heated to 98 ° C., and while maintaining this temperature, a silicic acid solution (SiO ₂₎ obtained by dealkalizing a sodium silicate aqueous solution with a cation exchange resin. A dispersion of core particles in which 3000 g (concentration of 3.5% by mass) was added to form a first silica coating layer was obtained. (Process (b))
Next, 1125 g of pure water is added to 500 g of the core particle dispersion liquid that has been washed with an ultrafiltration membrane to form a first silica coating layer having a solid content concentration of 13% by mass, and concentrated hydrochloric acid (35.5%) is further added dropwise. The pH was adjusted to 1.0 and dealumination was performed. Next, the aluminum salt dissolved in the ultrafiltration membrane was separated while adding 10 L of hydrochloric acid aqueous solution of pH 3 and 5 L of pure water, and SiO ₂ · Al from which some of the constituent components of the core particles forming the first silica coating layer were removed. A dispersion of ₂ O ₃ porous particles was prepared (step (c)). A mixture of 1500 g of the above porous particle dispersion, 500 g of pure water, 1,750 g of ethanol, and 626 g of 28% ammonia water is heated to 35 ° C., and then 104 g of ethyl silicate (SiO ₂ 28 mass%) is added. The surface of the porous particles on which the first silica coating layer was formed was coated with a hydrolyzed polycondensate of ethyl silicate to form a second silica coating layer. Next, a dispersion of silica-based fine particles (P-2) having a solid content concentration of 20% by mass, in which the solvent was replaced with ethanol using an ultrafiltration membrane, was prepared.

Table 5 shows the thickness, average particle diameter, MO _x / SiO ₂ (molar ratio), and refractive index of the first silica coating layer of the silica-based fine particles (P-2). Here, the average particle diameter was measured by a dynamic light scattering method, and the refractive index was measured in the same manner as described above.

  The following surface treatment was performed on the hard coat film with the back coat layer.

(surface treatment)
The hard coat films H1 to H4 with the back coat layer are immersed in a 1.5N-NaOH aqueous solution heated to 50 ° C. for 2 minutes for alkali treatment, washed with water, and then washed with a 0.5 mass% -H ₂ SO ₄ aqueous solution. It was immersed for 30 seconds at room temperature to neutralize, washed with water and dried.

  A low-refractive-index coating using the silica-based fine particles (P-2) was applied on the surface-treated hard coat film, and a low-refractive index layer was applied to produce an antireflection film.

<< Antireflection Film No. 1 >>
(Preparation of low refractive index layer)
A matrix (binder) in which Si (OC ₂ H ₅ ) ₄ is mixed at 95 mol% and CF ₃ (CF ₂ ) ₇ (CH ₂ ) ₂ Si (OCH ₃ ) ₃ at 5 mol% is mixed with the average particle diameter. FZ-2164 (Nippon Unicar), a nonionic surfactant composed of dimethylpolysiloxane and polyoxyalkylene, is added with 50% by mass of composite particles (P-2) having a refractive index of 60 nm and a refractive index of 1.38. Co., Ltd.) was added in an amount of 0.3 parts by mass to the matrix, and 1.0 mol / l-HCl was used as a catalyst, and a low refractive index coating solution diluted with a solvent was prepared. By applying the above-mentioned low refractive index coating liquid with a film thickness of 0.1 μm on the hard-coated film H1 subjected to the above surface treatment using a micro gravure method and drying at 120 ° C. for 1 minute, a refractive index of 1. No. 37 low refractive index layer was formed, and antireflection film No. It was set to 1.

<< Antireflection Film No. 2 >>
Anti-reflective film No. 1 except that the nonionic surfactant was changed to FZ-2207 (Nihon Unicar Co., Ltd.). In the same manner as in No. 1, a low refractive index coating solution was prepared. 2 was produced.

<< Antireflection Film No. 3 >>
Anti-reflective film No. 1 except that nonionic surfactant FZ-2164 was replaced with Emulgen 709 (manufactured by Kao Corporation), which is a polyoxyethylene alkyl ether nonionic surfactant of the same amount. In the same manner as described above, a low refractive index coating was prepared. 3 was produced.

<< Antireflection Film No. 4 >>
Again, the non-ionic surfactant FZ-2164 was replaced with an antireflective film No. 1 except that the same amount of a fluorosurfactant, Footage 250 (manufactured by Neos Co., Ltd.) was used. In the same manner as described above, a low refractive index coating was prepared. 4 was produced.

<< Antireflection Film No. 5 >>
Again, the non-ionic surfactant FZ-2164 was replaced with the same amount of dimethyl silicone oil (Nihon Unicar Co., Ltd., L-45 (5000)). In the same manner as described above, a low refractive index coating was prepared. 5 was produced.

<< Antireflection Film No. 6 >>
Antireflection film No. 1, a matrix (binder) mixed with 95 mol% of Si (OC ₂ H ₅ ) _{4 and 5} mol% of CF ₃ (CF ₂ ) ₇ (CH ₂ ) ₂ Si (OCH ₃ ) ₃ is mixed with a fluorine-containing copolymer ( Instead of paint (solid content 3%) containing a polydimethylsiloxane unit (fluoroolefin / vinyl ether copolymer) (manufactured by JSR Corporation, Opstar JN-7215), the amount was adjusted to be the same as the solid content. ), Other than that, a low refractive index coating solution was prepared in the same manner, and applied in the same manner to apply an antireflection film No. 6 was produced.

<< Antireflection Film No. 7 >>
Using H2 instead of the hard coat film H1 with the back coat layer, the antireflection film No. 5 was similarly used. 2 using the same low refractive index coating as used in 7 was produced.

<< Antireflection Film No. 8 >>
The antireflection film No. 1 was used except that H3 was used instead of the hard coat film H1 with a backcoat layer. In the same manner as in FIG. 8 was produced.

<< Antireflection Film No. 9 >>
The antireflection film No. 1 was used except that H4 was used instead of the hard coat film H1 with a backcoat layer. In the same manner as in FIG. 9 was produced.

  The antireflection film no. About 1-9, the reflection nonuniformity, the surface abrasion system, and antifouling property were evaluated as follows, respectively.

<Evaluation of visual unevenness>
A sample of width direction × length direction 50 cm was subjected to light absorption treatment using black spray on the back surface, and reflection of a fluorescent lamp was observed from the surface to evaluate unevenness of reflected light.

◎ No unevenness is observed. ○ Slight unevenness is observed. △ Unevenness is observed. × Clearly unevenness is observed.

<Surface wear resistance>
The number of scratches per centimeter in the steel wool reciprocation direction was evaluated after 10 rounds of the surface of the laminate film were applied to # 0000 steel wool with a weight of 0.8 kg per square centimeter. The smaller the number of scratches, the better. However, if it is 5 or less, it is good, if it is 6-10, it can be used, and more than 10 cannot be used.

<Evaluation of antifouling properties>
After writing letters on the sample surface with black oily magic (Mckey extra fine manufactured by ZEBRA), it was wiped until clean using Bencot (BEMCOT M-3 manufactured by Asahi Kasei Co., Ltd.). This was repeated several times at the same location, and repeated antifouling properties were evaluated according to the following criteria.

A: Repeatedly wipe lightly 50 times or more and then write a character with magic. Then, the surface will repel ink. ○: Repeatedly lightly wipe up to 20 times and then write a character with magic. Bleeding Δ: Repeatedly wiping up to 5 times, and then ink writing on the surface when writing characters with magic. The results are shown below.

B: a binder (matrix) component,
B1: 95 mol% of Si (OC ₂ H ₅ ) ₄ (TEOS), ₅ mol% of CF ₃ (CF ₂ ) ₇ (CH ₂ ) ₂ Si (OCH ₃ ) ₃
B2: Fluorine copolymer (fluoroolefin / vinyl ether copolymer having a polydimethylsiloxane unit) manufactured by JSR Corporation, OPSTAR JN-7215
C: a nonionic surfactant having a hydrophobic group composed of dimethylpolysiloxane and a hydrophilic group composed of polyalkylene oxide,
C1; FZ2164 manufactured by Nihon Unicar Co., Ltd.
C2: Nippon Unicar Co., Ltd. FZ2207
C3: polyoxyethylene alkyl ether nonionic surfactant (Emulgen 709 manufactured by Kao Corporation)
C4: Fluorosurfactant (Foogent 250 manufactured by Neos Co., Ltd.)
C5: Dimethyl silicone oil (Nihon Unicar Co., Ltd. L-45 (5000))
Represents.

  From the above, it can be seen that the antireflection film according to the present invention has no uneven reflection, excellent surface wear resistance, and good antifouling properties.

In addition, when surface specific resistance is measured on 500V conditions, the antireflection film No. which uses an antistatic agent for a hard-coat layer. 8 is preferred. 8 was 5.2 × 10 ⁸ Ω, which was a preferable result. Other films were in the range of 1.0 × 10 ¹² to 10 × 10 ¹³ and had no antistatic effect.

Example 2
The antireflection film No. 1 prepared in Example 1 was used. 8, when producing a hard coat film, titanium oxide fine particles having an average particle size of 0.5 μm are applied to the active ray curable resin layer coating solution 1 used for forming the active ray curable resin layer (lower layer). The same method was used except that a hard coat film containing antimony oxide particles having an average particle size of 0.03 μm was used in the hard coat upper layer produced in the same manner except that 25% by mass of the solid content was added. Thus, the antireflection film No. having an antiglare surface was used. 10 was produced.

  When the same evaluation as in Example 1 was performed, the antireflection film No. 1 in Example 1 was used. The result was the same as in Example 8.

Example 3
The following coating solution for medium refractive index layer is applied on the hard coat layers of the hard coat films H1 to H4 with the back coat layer prepared as described above using a bar coater, dried at 60 ° C., and then irradiated with ultraviolet rays. The layer is cured, and a medium refractive index layer (refractive index 1.72) is coated thereon with the following coating liquid for a high refractive index layer using a bar coater. After drying at 60 ° C., ultraviolet rays are applied. The coating layer was cured by irradiation to form a high refractive index layer (refractive index 1.9).

[Preparation of medium refractive index layer / high refractive index layer]
(Preparation of titanium dioxide dispersion)
Titanium dioxide (primary particle mass average particle size: 50 nm, refractive index: 2.70) 30 parts by mass, anionic diacrylate monomer (PM21, Nippon Kayaku Co., Ltd.) 4.5 parts by mass, cationic methacrylate monomer ( DMAEA (manufactured by Kojin Co., Ltd.) (0.3 parts by mass) and methyl ethyl ketone (65.2 parts by mass) were dispersed by a sand grinder to prepare a titanium dioxide dispersion.

(Preparation of coating solution for medium refractive index layer)
In 151.9 g of cyclohexanone and 37.0 g of methyl ethyl ketone, 0.14 g of a photopolymerization initiator (Irgacure 907, manufactured by Ciba Geigy) and 0.04 g of a photosensitizer (Kayacure DETX, manufactured by Nippon Kayaku Co., Ltd.) were dissolved. Further, 6.1 g of the above titanium dioxide dispersion and 2.4 g of a mixture of dipentaerythritol pentaacrylate and dipentaerythritol hexaacrylate (DPHA, manufactured by Nippon Kayaku Co., Ltd.) were added and stirred at room temperature for 30 minutes. The solution was filtered through a polypropylene filter having a pore diameter of 0.4 μm to prepare a medium refractive index layer coating solution. When this coating solution was applied to a cellulose ester film and dried and the refractive index after UV curing was measured, a medium refractive index layer having a refractive index of 1.72 was obtained.

(Preparation of coating solution for high refractive index layer)
In 1152.8 g of cyclohexanone and 37.2 g of methyl ethyl ketone, 0.06 g of a photopolymerization initiator (Irgacure 907, manufactured by Ciba Geigy) and 0.02 g of a photosensitizer (Kayacure DETX, manufactured by Nippon Kayaku Co., Ltd.) were dissolved. Further, 0.01 g of FZ2207 (manufactured by Nihon Unicar Co., Ltd.) was added, and the above titanium dioxide dispersion and a mixture of dipentaerythritol pentaacrylate and dipentaerythritol hexaacrylate (DPHA, Nippon Kayaku Co., Ltd.) Increase the ratio of titanium dispersion, adjust the amount to be the refractive index of the high refractive index layer, stir at room temperature for 30 minutes, then filter with a polypropylene filter with a pore size of 0.4μm, high refractive index A layer coating solution was prepared. When this coating solution was applied to a cellulose ester film, dried and the refractive index after UV curing was measured, a high refractive index layer having a refractive index of 1.9 was obtained.

(Production of low refractive index layer)
An antireflection film was prepared by coating a low refractive index layer as follows on the hard coat film coated with the medium refractive index layer and the high refractive index layer.

<< Antireflection Film No. 11 >>
Furthermore, on the high refractive index layer formed on the hard coat film H1, the antireflection film No. 1 was used. The low refractive index coating liquid used in 1 was applied at a film thickness of 0.1 μm using a micro gravure method, and dried at 120 ° C. for 1 minute to form a low refractive index layer having a refractive index of 1.37, Antireflection film No. It was set to 11.

<< Antireflection Film No. 12 >>
Antireflection film No. For the low refractive index coating solution used in No. 11, an antireflection film No. 1 was used except that the nonionic surfactant was changed to FZ-2207 (manufactured by Nippon Unicar Co., Ltd.). In the same manner as in No. 11, a low-refractive-index coating solution was prepared. 12 was produced.

<< Antireflection Film No. 13 >>
Antireflection film No. For the low refractive index coating solution used in No. 11, non-ionic surfactant FZ-2164 is also added to Emulgen 709 (manufactured by Kao Corporation), which is the same amount of polyoxyethylene alkyl ether nonionic surfactant. The antireflection film no. In the same manner as in No. 11, a low refractive index coating was prepared. 13 was produced.

<< Antireflection Film No. 14 >>
Antireflection film No. For the low refractive index coating solution used in No. 11, the non-ionic surfactant FZ-2164 was replaced with the same amount of fluorosurfactant, Phageent 250 (manufactured by Neos Co., Ltd.). Antireflection film No. In the same manner as in No. 11, a low refractive index coating was prepared. 14 was produced.

<< Antireflection Film No. 15
Antireflection film No. 11 except that the non-ionic surfactant FZ-2164 was replaced with the same amount of dimethyl silicone oil (L-45 (5000) manufactured by Nihon Unicar Co., Ltd.). Prevention film No. In the same manner as in No. 11, a low refractive index coating was prepared. 15 was produced.

<< Antireflection Film No. 16 >>
Antireflection film No. 11, a matrix (binder) mixed with 95 mol% of Si (OC ₂ H ₅ ) _{4 and 5} mol% of CF ₃ (CF ₂ ) ₇ (CH ₂ ) ₂ Si (OCH ₃ ) ₃ in a low refractive index coating solution, Instead of paint (solid content 3%) containing a fluorine-containing copolymer (fluoroolefin / vinyl ether copolymer having a polydimethylsiloxane unit) (manufactured by JSR Co., Ltd., OPSTAR JN-7215) (same as solid content) Otherwise, the low refractive index coating solution was prepared in the same manner, and applied in the same manner to apply the antireflective film no. 16 was produced.

<< Antireflection Film No. 17 >>
In the same manner, the antireflective film No. 1 was formed on the high refractive index layer of the medium provided with the medium refractive index layer and the high refractive index layer using H2 instead of the hard coat film H1 with the back coat layer. Using the same low refractive index coating as that used for No. 12, a low refractive index layer was provided, and antireflection film No. 17 was produced.

<< Antireflection Film No. 18 >>
Other than using H3 instead of the hard coat film H1 with the back coat layer, the antireflection film No. 1 was used. In the same manner as in FIG. 18 was produced.

<< Antireflection Film No. 19 >>
The antireflection film No. 1 was used except that H4 was used instead of the hard coat film H1 with a backcoat layer. In the same manner as in FIG. 19 was produced.

  The antireflection film no. About 11-19, the result similar to Example 2 was obtained as a result of evaluating similarly to Example 2 about reflection nonuniformity, a surface abrasion system, and antifouling property, respectively. That is, the antireflection film No. 1 according to the present invention. Nos. 11, 12, and 16 to 19 show no reflection unevenness, excellent surface wear resistance, and good antifouling properties.

Example 4
A polarizing plate was prepared using each antireflection film.

[Preparation of polarizing plate]
A polyvinyl alcohol film having a thickness of 120 μm was uniaxially stretched (temperature: 110 ° C., stretch ratio: 5 times). This was immersed in an aqueous solution composed of 0.075 g of iodine, 5 g of potassium iodide and 100 g of water for 60 seconds, and then immersed in an aqueous solution of 68 ° C. composed of 6 g of potassium iodide, 7.5 g of boric acid and 100 g of water. This was washed with water and dried to obtain a polarizing film.

  Subsequently, according to the following processes 1-5, the polarizing film, the said antireflection film, and the cellulose ester film of the back side were bonded together, and the polarizing plate was produced. A cellulose ester film having a retardation (measured at 590 nm, in-plane retardation Ro = 43 nm, retardation in the thickness direction Rt = 135 nm) was used as a polarizing plate for the cellulose ester film on the back side.

  Step 1: Soaked in a 2 mol / l sodium hydroxide solution at 60 ° C. for 90 seconds, then washed with water and dried to obtain a saponified cellulose ester film on the side to be bonded to the polarizer.

  On the other hand, the surface of the anti-reflection layer side of the hard coat film on which the anti-reflection layer was formed was subjected to the saponification treatment while applying a peelable polyethylene film and protecting it from alkali.

  Step 2: The polarizing film was immersed in a polyvinyl alcohol adhesive tank having a solid content of 2% by mass for 1 to 2 seconds.

  Step 3: Gently wipe off excess adhesive adhered to the polarizing film in Step 2 and place it on the cellulose ester film treated in Step 1 so that the anti-reflection layer of the hard coat film is on the outside Laminated and placed.

Step 4: Excess adhesive and bubbles were removed from the end of the laminate of the antireflection film, the polarizing film and the cellulose ester film sample laminated in Step 3 with a hand roller, and bonded together. The pressure of the hand roller was 20 to 30 N / cm ² and the roller speed was about 2 m / min.

  Process 5: The sample which bonded the polarizing film produced in the process 4, the cellulose-ester film, and the antireflection film in the 80 degreeC dryer was dried for 2 minutes, and the polarizing plate was produced. The antireflection film No. 1 to 19 are used for polarizing plate No. 1-19 were produced.

[Production of liquid crystal display device]
A liquid crystal panel for viewing angle measurement was produced as follows, and the characteristics as a liquid crystal display device were evaluated.

  The polarizing plates on both sides of the 15-inch display VL-150SD manufactured by Fujitsu were previously peeled off, and the above-prepared polarizing plates 1 to 19 were each stuck to the glass surface of the liquid crystal cell.

  At that time, the direction of bonding of the polarizing plate is such that the surface of the optical compensation film (retardation film) is on the liquid crystal cell side, and the absorption axis is in the same direction as the polarizing plate previously bonded. The liquid crystal display device no. 1 to 19 were produced.

[Evaluation]
<Evaluation of visibility>
For each of the liquid crystal display devices thus obtained, when the reflection image of the fluorescent lamp is viewed, the antireflection film of the present invention is a reflection image like a mirror, whereas the comparative polarizing plate has a fine wave The shape of the fluorescent lamp appeared to be finely distorted.

  Moreover, about each liquid crystal display device, the screen was set as black display and the reflective unevenness of the surface was evaluated visually.

  In the liquid crystal display device of the present invention, the color unevenness of the reflected light is not known, and the black color appears to be dark. The liquid crystal display device using 3, 4, 5, or 13, 14, 15 was in a state in which the color unevenness of the reflected light was considerably concerned.

Claims (12)

A refractive index containing at least the following three components (A), (B), and (C) directly or indirectly on a hard coat layer by providing a hard coat layer mainly composed of an active energy ray-curable resin on a transparent film. Is provided with a (low refractive index) layer in the range of 1.20 to 1.42.
(A) Composite particles having porous particles and a coating layer provided on the surface of the porous particles, or hollow particles filled with a solvent, gas, or porous substance inside (B) binder component (C) hydrophobic group Is a nonionic surfactant composed of dimethylpolysiloxane and hydrophilic group polyoxyalkylene The antireflective film according to claim 1, wherein the binder component represented by (B) is formed by a sol-gel method by hydrolysis polycondensation of alkoxysilane. The antireflection film according to claim 2, wherein 50% by mass or more of the alkoxysilane is tetraethoxysilane. The hard coat layer contains an active energy ray-curable resin component and metal oxide fine particles as main components, and the low refractive index layer is provided directly on the hard coat layer. The antireflection film according to any one of the above. 5. The hard coat layer contains a nonionic surfactant composed of dimethylpolysiloxane as a hydrophobic group represented by (C) and a polyoxyalkylene as a hydrophilic group. Antireflection film. The hard coat layer contains metal oxide fine particles selected from Zr, Sn, Sb, As, Zn, Nb, In, and Al, according to any one of claims 1 to 5. Antireflection film. A nonionic surfactant composed of dimethylpolysiloxane having a hydrophobic group represented by (C) and a polyoxyalkylene having a hydrophilic group is a linear form in which dimethylpolysiloxane and polyoxyalkylene are alternately and repeatedly bonded. The antireflection film according to claim 1, wherein the antireflection film is a block copolymer of the following. The hard coat layer is composed of two or more layers, and at least one of an antistatic agent, a visible light region color tone adjusting agent, an electromagnetic wave blocking agent, and an infrared absorber is added to one of the layers. The antireflection film according to any one of claims 1 to 7. The antireflection film according to any one of claims 1 to 8, wherein the hard coat layer contains antiglare fine particles having a particle size of 0.1 to 1.0 µm. In the case of having a high refractive index layer, or a middle refractive index layer and a high refractive index layer between the hard coat layer and the low refractive index layer, the layer in contact with the low refractive index layer is represented by (C). The antireflective film of any one of Claims 1-4 and 6-9 characterized by the above-mentioned. A polarizing plate using the antireflection film according to claim 1. An image display device using the antireflection film according to claim 1.