Production method for antireflection laminate

Field of invention

The present invention relates to a method for producing an antireflection laminate having a low refractive index and excellent mechanical strength, which forms a coating layer of an ionizing radiation curable resin composition containing hollow silica fine particles having an ionizing radiation curable group.

The display surface of an image display device such as a liquid crystal display (LCD) or a cathode ray tube display device (CRT) is required to have less reflection of light rays emitted from an external light source such as a fluorescent lamp in order to improve its visibility. ..

Conventionally, it has been known that the reflectance is reduced by coating the surface of a transparent object with a transparent film having a low refractive index. Visibility can be improved by providing an antireflection film utilizing such a phenomenon on the display surface of the image display device. The antireflection film has a single-layer structure in which a low refractive index layer is provided on the display surface, or a medium to high refractive index layer is provided in one or more layers on the display surface in order to improve the antireflection performance. , There is a multi-layer structure in which a low refractive index layer is provided on the layer.

The single-layer type antireflection film has a simpler layer structure than the multi-layer type, so that it is excellent in productivity and cost performance. On the other hand, the multi-layer type antireflection film can improve the antireflection performance by combining the layer configurations, and it is easier to improve the performance as compared with the single layer type.

The method for forming the low refractive index layer is generally roughly classified into a vapor phase method and a coating method. The vapor phase method includes a physical method such as a vacuum vapor deposition method and a sputtering method, and a chemical method such as a CVD method, and the coating method includes a roll coating method, a gravure coating method, a slide coating method, a spray method, and a dipping method. , Screen printing method, etc.

When a low refractive index layer is formed by the vapor phase method, it is possible to form a transparent thin film with high functionality and high quality, but precise atmosphere control in a high vacuum system is required. Further, since a special heating device or an ion generation accelerator is used, there is a problem that the manufacturing device is complicated and large in size, and the manufacturing cost is inevitably high. Further, in the case of the vapor phase method, it is difficult to form a transparent thin film having a large area or uniformly form a transparent thin film on the surface of a film or the like having a complicated shape.

On the other hand, when it is formed by the spray method among the coating methods, there is a problem that the utilization efficiency of the coating liquid is poor and it is difficult to control the film forming conditions. When the roll coating method, gravure coating method, slide coating method, dipping method, screen printing method, etc. are used, the utilization efficiency of the film-forming raw material is good and it is excellent in mass production and equipment cost, but generally, the coating method is used. The obtained transparent thin film has a problem that its function and quality are inferior to those obtained by the vapor phase method.

As a coating method, a coating liquid composed of a polymer containing a fluorine atom in the molecule is applied to the surface of the base material and dried, or the molecule is composed of a monomer containing a functional group that is cured by ionizing radiation or heat. It is known that a coating liquid is applied to the surface of a base material, dried, and then the monomer is cured by UV irradiation, heat, or the like to form a low refractive index layer.

The higher the fluorine atom content, the lower the refractive index of the coating film made of a binder containing fluorine atoms. Further, when the fluorine atom content of the coating film is high, the antifouling property is improved. However, when the fluorine atom content in the coating film is high, there is a problem that the hardness and strength of the coating film are lowered.

As another method for reducing the refractive index, air having a refractive index of 1 can be made larger than the wavelength of visible light and contained inside the coating film to reduce the refractive index of the entire coating film. Are known.

Japanese Patent Application Laid-Open No. 2000-64601 (Patent Document 1) states that a low refractive index layer having a very fine porous structure is formed by forming microvoids having an average diameter of 200 nm or less in a coating film made of a fluorine atom-containing polymer. Is disclosed. However, if the amount of microvoids is increased too much in order to lower the refractive index, there is a problem that the hardness and strength of the coating film are lowered.

Further, in Japanese Patent Application Laid-Open No. 6-3501 (Patent Document 2), a low refractive index having a very minute porous structure is obtained by utilizing voids formed by gas generated by extraction or thermal decomposition. The layers are disclosed. However, similarly to the above, if the amount of these voids is too large, there is a problem that the hardness and strength of the coating film are lowered.

Further, in JP-A-2001-167637 (Patent Document 3) and JP-A-2002-225866 (Patent Document 4), hollow fine particles such as hollow silica having a cavity inside are hydrolyzed and polycondensed with alkoxysilane. A low refractive index layer dispersed in a binder containing an inorganic component obtained from a substance is disclosed. This low refractive index layer has the same effect as the low refractive index layer having a large number of microvoids, and since the microvoids are protected by a hard outer shell such as silica, a certain degree of coating film hardness can be obtained. Have.

However, while a hard coating film is formed by a binder containing an inorganic component, it is fragile against an external impact, so that there is a problem that the mechanical strength of the coating film, particularly scratch resistance, is inferior.

Further, the agglomeration effect of the hollow silica particles makes it possible to obtain a harder coating film than the case of the coating film alone, but the brittleness is also increased, so that it is difficult to realize a coating film having a low refractive index and excellent mechanical strength.

In the previous application filed by the applicant of the present application, porous fine particles that can be expected to have the effect of forming microvoids and fine particle aggregates in which voids are formed by aggregation of particles are used, and the mechanical properties (elasticity, etc.) of the film are used as the binder component. It is proposed that an antireflection film having improved mechanical strength can be obtained by using an ionizing radiation curable resin composition that can be easily controlled.

However, if the amount of silica particles added is increased to some extent, silica fine particles agglomerate and the mechanical strength of the coating film drops at once. Therefore, an antireflection film having a low refractive index and excellent mechanical strength is still required. There is.<patcit num="1"><text>Japanese Unexamined Patent Publication No. 2000-64601</text></patcit><patcit num="2"><text>Japanese Patent Application Laid-Open No. 6-3501</text></patcit><patcit num="3"><text>Japanese Unexamined Patent Publication No. 2001-167637</text></patcit><patcit num="4"><text>Japanese Patent Application Laid-Open No. 2002-225866</text></patcit>

The present invention has been achieved in view of the above problems, and an object of the present invention is to form a coating layer of an ionizing radiation curable resin composition containing hollow silica fine particles having an ionizing radiation curable group, which has a low refractive index. An object of the present invention is to provide an antireflection laminate having a high rate and excellent mechanical strength. In order to solve the above problems, the antireflection laminate according to the present invention is an antireflection laminate in which a low refractive index layer having a refractive index of at least 1.45 or less is provided on a light transmissive substrate. The low refractive index layer comprises an ionizing radiation curable resin composition and silica fine particles having an outer shell layer and having a porous or hollow inside. A part or all of the silica fine particles are formed by treating at least a part of the surface of the silica fine particles with a silane coupling agent having an ionizing radiation curable group.

According to the present invention, the silica fine particles have fine voids on the outside and inside, and are filled with a gas, for example, air having a refractive index of 1, so that the refractive index of the silica fine particles themselves is low and the coating film is coated. The refractive index of the coating film can be lowered even when the particles are uniformly dispersed without forming an aggregate inside. That is, the silica fine particles having voids have a lower refractive index of 1.20 to 1.45 and a refractive index of 1.45 or less, preferably 1.45 or less, as compared with ordinary silica fine particles having no gas inside (refractive index n = 1.46). Can be 1.40 or less. Further, since the voids are protected by the outer shell of the fine particles, the formed coating film is tightened by the cohesive force and hardness of the fine particles dispersed in the cured resin composition, and the mechanical strength of the coating film is increased. improves.

Further, these fine particles are slightly aggregated in the coating film, and particularly, fine irregularities of about the wavelength of visible light or less are formed on the outermost surface of the coating film. As a result, since a nanoporous structure is formed inside or on the surface of the coating film, a structure in which air is taken in is realized as compared with only a resin that becomes a normal flat film. Therefore, an effect more than the effect of the refractive index of the fine particles can be expected. Further, even when the content of the silica fine particles in the resin composition is very large, it is possible to avoid a significant decrease in the hardness and strength of the coating film.

Furthermore, since a silane coupling agent having an ionizing radiation curable group is introduced into at least a part of the surface of the silica fine particles, the affinity with the binder component is improved, and the silica fine particles in the coating liquid or the coating film are improved. Can be uniformly dispersed.

Furthermore, the ionizing radiation curable group of the silane coupling agent introduced into this surface is directly with the ionizing radiation curable group of the binder component and / or via the ionizing radiation curable group of the free silane coupling agent. Since covalent bonds are formed by a chemical reaction, the silica fine particles serve as a cross-linking agent for the binder component, and even when the amount of the silica fine particles with respect to the resin composition is very large, it is possible to avoid a significant decrease in the hardness and strength of the coating film. It is possible to realize a low refractive index layer having a low refractive index and excellent mechanical strength.

Specific description of the invention

The low refractive index layer constituting the antireflection laminate according to the present invention comprises an ionizing radiation curable resin composition that functions as a binder component and silica fine particles. Hereinafter, each of these components will be described.

1.<u style="single">Ionizing radiation curable resin composition</u> The ionizing radiation curable resin composition used in the present invention includes at least one hydrogen bond-forming group in one molecule and a functional group that cures with three or more ionizing radiation (simply "ionizing radiation curable group"). It is desirable to include a compound having (sometimes referred to as). As described above, the resin composition is coated with the resin composition by having an ionizing radiation curable group that is cured by ionizing radiation and a hydrogen bond forming group that is thermosetting by itself or in combination with a curing agent. When the liquid is applied to the surface of the object to be coated, dried, and irradiated with ionizing radiation or irradiation with ionizing radiation and heating, chemical bonds such as crosslinks are formed in the coating film, and the coating film is formed. It can be cured efficiently.

The "ionizing radiation-curable group" in the specification of the present application means a functional group capable of curing a coating film by advancing a polymerization reaction or a cross-linking reaction by irradiation with ionizing radiation, for example, photoradical polymerization. , Photocationic polymerization, polymerization reaction such as photoanionic polymerization, or reaction type such as addition polymerization or reduced polymerization which proceeds through photodimerization. In particular, ethylenically unsaturated bonds such as (meth) acryloyl groups, vinyl groups, and allyl groups are photoradically polymerized directly or indirectly by the action of an initiator by irradiation with ionizing radiation such as ultraviolet rays or electron beams. Since the reaction can be generated, the handling including the photocuring step is relatively easy. Among these, the (meth) acryloyl group is preferable because it has excellent productivity and the mechanical strength of the coating film after curing can be easily controlled.

The "hydrogen bond-forming group" in the specification of the present application is a functional group capable of curing a coating film by advancing a polymerization reaction or a cross-linking reaction between the same functional groups or other functional groups by heating. Meaning, for example, an alkoxy group, a hydroxyl group, a carboxyl group, an amino group, an epoxy group, and the like can be exemplified.

Among these functional groups, the hydroxyl group also has an excellent affinity with the surface-treated silica fine particles, so that the dispersibility of the surface-treated silica fine particles in the binder can be improved. Since the hydroxyl groups are easily introduced into the binder component and are adsorbed on the hydroxyl groups on the surface of the silica fine particles, they can be uniformly dispersed in the coating liquid or the coating film. Therefore, the life of the coating liquid is improved, and the transparency and the film strength of the coating film are not lowered due to the aggregation of the silica fine particles, so that a uniform coating film can be formed.

Further, at the time of curing, by thermosetting alone or in combination with a curing agent, the binder components or the binder and the hydroxyl group on the surface of the silica fine particles form a covalent bond to further improve the coating film strength. Can be planned. In this case, the silica fine particles act as a cross-linking agent in the binder.

As the monomers preferably used in the above-mentioned ionizing radiation curable resin composition, those having a hydrogen bond forming group such as a hydroxyl group are used. The hydrogen bond-forming group may be produced as a by-product during synthesis and may be mixed as a part of the monomer. Specifically, tri (meth) acrylates such as ethylene glycol di (meth) acrylate and pentaerythritol di (meth) acrylate monostearate, trimethylolpropane tri (meth) acrylate, and pentaerythritol tri (meth) acrylate. Examples thereof include (meth) acrylate, polyfunctional (meth) acrylate such as pentaerythritol tetra (meth) acrylate derivative and dipentaerythritol penta (meth) acrylate.

In addition to these, epoxy acrylate resins having OH residues (such as "epoxy ester" manufactured by Kyoeisha Chemical Co., Ltd. and "lipoxy" manufactured by Showa Polymer Co., Ltd.) and various isocyanates and monomers having a hydroxyl group are heavily added via urethane bonds. The number average molecular weight (polystyrene-equivalent number average molecular weight measured by the GPC method) containing hydrogen bond-forming groups such as urethane acrylate resin (Shikou manufactured by Nippon Synthetic Chemical Industry Co., Ltd. and Urethane acrylate manufactured by Kyoeisha Chemical Co., Ltd.) obtained by Oligomers of 20,000 or less can also be preferably used.

These monomers and oligomers are excellent in the effect of increasing the crosslink density of the coating film, and also have high fluidity because the number average molecular weight is as small as 20,000 or less, and are excellent in coating suitability.

Further, if necessary, a (co) polymer containing a monomer having a hydrogen bond forming group, such as a reactive polymer having a (meth) acrylate group in the main chain or side chain and having a number average molecular weight of 20,000 or more is also available. It can be preferably used. As these reactive polymers, for example, a commercially available product such as "macromonomer" (manufactured by Toa Synthetic) can be used, or a copolymer of methyl methacrylate and glycidyl methacrylate is prepolymerized and later. A reactive polymer having a (meth) acrylate group may be obtained by condensing the glycidyl group of the copolymer with the carboxyl group of methacrylic acid or acrylic acid.

By containing these components having a large molecular weight, the film-forming property on a substrate having a complicated shape such as an antiglare layer is improved, and the curl and warpage of the antireflection laminate due to volume shrinkage during curing are reduced.

The above-mentioned monomers, oligomers, and polymers, and monomers, oligomers, and polymers that do not belong to the above are appropriately combined to contain hydrogen bond-forming groups having film-forming property, coating suitability, cross-linking density for ionizing radiation curing, and thermosetting property. Various properties such as quantity can be adjusted. For example, the monomer and oligomer improve the crosslink density and processability, and the polymer improves the film formation property of the coating composition.

In the present invention, various properties of the coating film can be easily adjusted by appropriately combining a monomer and / or oligomer having a number average molecular weight of 20,000 or less and a polymer having a number average molecular weight of 20,000 or more.

2.<u style="single">Silica fine particles</u> In the specification of the present application, "silica fine particles having an outer shell layer and having a porous or hollow inside" refers to a structure in which gas is filled inside the silica fine particles and / or a porous structure containing gas. Means what you have. When the gas is air having a refractive index of 1.0, the refractive index decreases in proportion to the occupancy of air in the fine particles as compared with the original refractive index of the fine particles.

The silica fine particles used in the antireflection laminate according to the present invention may have a refractive index of 1.20 to 1.44 and are not particularly limited. Examples of such silica fine particles include composite oxide sol or hollow silica fine particles disclosed in JP-A-7-133105 and JP-A-2001-233611. Specifically, such hollow silica fine particles can be produced by the following first to third steps. In a preferred embodiment of the present invention, it may be further subjected to a fourth step.

That is, as the first step, an alkaline aqueous solution of a silica raw material and an inorganic oxide raw material other than silica is individually prepared, or a mixed aqueous solution of both is prepared. Next, the obtained aqueous solution is gradually added to an alkaline aqueous solution having a pH of 10 or higher with stirring according to the composite ratio of the target composite oxide. Instead of the first step, it is also possible to use a dispersion liquid containing seed particles in advance as a starting material.

Next, as a second step, at least a part of elements other than silicon and oxygen is selectively removed from the colloidal particles made of the composite oxide obtained in the above step. Specifically, the elements in the composite oxide are dissolved and removed using a mineral acid or an organic acid, or ion exchanged and removed by contacting with a cation exchange resin.

Subsequently, as a third step, the surface of the colloidal particles is hydrolyzable organic by adding a hydrolyzable organic silicon compound, a silicic acid solution, or the like to the colloidal particles of the composite oxide from which some elements have been removed. Coat with a polymer such as a silicon compound or silicic acid solution. In this way, the composite oxide sol described in the above publication can be produced.

Further, in the present invention, as the fourth step, it is preferable to hydrothermally treat the silica fine particles obtained above in the range of 50 to 300 ° C. Various low molecular weight compounds are present as ionic impurities on the surface of the silica fine particles obtained by the above manufacturing process. These impurities are caused by those contained in the raw material of the silica fine particles, additives added in the manufacturing process, and the like. In the present invention, the amount of impurities on the surface of the silica fine particles is reduced to a predetermined amount or less by removing the ionic impurities by hydrothermal treatment.

Specifically, the content of the alkali metal oxide in the silica fine particles is 10 ppm or less, preferably 5 ppm or less, and more preferably 2 ppm or less. In particular, by setting the content of the alkali metal oxide to 5 ppm or less, the stability of the coating liquid containing silica fine particles is improved. That is, even when the coating liquid is stored for a long period of time, an increase in the viscosity of the coating liquid can be suppressed, and excellent storage stability can be realized. Further, by setting the content of the alkali metal oxide in the above range, it is presumed that the reaction between the surface of the silica fine particles and the silane coupling agent occurs more strongly, and as a result, the coating film strength is also improved. If the content of the alkali metal oxide exceeds 10 ppm, the film-forming property is lowered and the strength of the obtained coating film becomes insufficient. The content of alkali metal oxide is M.₂It means the content as O (M represents an alkali metal element), and the content can be measured by a general atomic absorption method or ICP MS measurement.

The content of ammonia (including ammonium ions) in the silica-based fine particles is 2000 ppm or less, preferably 1500 ppm or less, and more preferably 1000 ppm or less. In particular, by setting the ammonia content to 1500 ppm or less, the stability of the coating liquid containing silica fine particles is improved. That is, even when the coating liquid is stored for a long period of time, an increase in the viscosity of the coating liquid can be suppressed, and excellent storage stability can be realized. Further, by setting the ammonia content in the above range, it is presumed that the reaction between the surface of the silica fine particles and the silane coupling agent occurs more strongly, and as a result, the coating film strength is also improved. When the content of ammonia exceeds 2000 ppm, the film-forming property is lowered and the strength of the obtained coating film becomes insufficient as described above . The content of ammonia (including ammonium ions) in the silica-based fine particles is NH.₃The content can be measured by a general chemical analysis method.

In order to keep the content of the impurity compound in the silica fine particles within the above range, in the present invention, the hydrothermal treatment step may be repeated a plurality of times as the fourth step. By repeating the hydrothermal treatment, the content of alkali metal oxide and / or ammonia (including ammonium ion) in the obtained silica-based fine particles can be reduced.

When the hydrothermal treatment temperature is less than 50 ° C, the content of alkali metal oxide and / or ammonia in the finally obtained silica fine particles or silica fine particle dispersion is not effectively reduced, so that the coating liquid is stored. Stability is not improved, and improvement in film strength cannot be expected. On the other hand, if the hydrothermal treatment temperature exceeds 300 ° C, not only the storage stability and film strength of the coating liquid are not improved, but also silica fine particles may aggregate in some cases.

The average particle size of the silica fine particles used in the present invention is preferably in the range of 5 to 100 nm, preferably 30 to 60 nm. The silica fine particles used are appropriately selected according to the thickness of the coating film to be formed, and are preferably in the range of 2/3 to 1/10 of the thickness of the coating film.

When the average particle size of the silica fine particles is in the range of 5 to 100 nm, the outer shell layer of the silica fine particles is preferably in the range of 1 to 30 nm, preferably 2 to 20 nm. If the thickness of the outer shell layer is less than 1 nm, it may not be possible to completely cover the particles, and binder components and the like may invade the inside of the fine particles to reduce internal cavities and porous structures, resulting in a low refractive index. The effect of is not enough. On the other hand, if the thickness of the outer shell layer exceeds 30 nm, the porosity of the fine particles may decrease and the effect of low refractive index may not be sufficiently obtained.

Since the silica fine particles in the present invention have cavities and a porous structure inside the hard outer shell layer of silica, the film strength when combined with the binder component is also improved, and the refractive index required as a low refractive index layer is 1.45 or less. Easy to achieve.

The silica fine particles are further surface-treated with a silane coupling agent having an acryloyl group and / or a methacryloyl group. The surface treatment of the silica fine particles improves the affinity for the ionizing radiation curable resin composition binder mainly composed of organic components, enables uniform dispersion of the silica fine particles in the coating liquid and the coating film, and enables uniform dispersion of the silica fine particles among the silica fine particles. It is possible to prevent a decrease in transparency and coating strength due to aggregation and enlargement of particles.

The silane coupling agent having an acryloyl group and / or a methacryloyl group has ionizing radiation curability and easily reacts with the ionizing radiation curable group of the binder component, and the silica fine particles in the coating film become the binder component. It is fixed. That is, the silica fine particles act as a cross-linking agent in the binder. As a result, the hardness of the coating film due to the tightening effect of the entire film is improved, and the hardness can be imparted while retaining the original flexibility of the binder component. Therefore, since the coating film itself is deformed, it has an absorbing force against an external impact and a restoring force after the deformation, so that the occurrence of scratches can be suppressed.

In the present invention, the content of the impurity compound in the silica fine particles, that is, the alkali metal oxide and ammonia is within the above range, and the silane coupling agent is introduced into the silica fine particles having few impurities. An antireflection laminate having excellent coating strength can be obtained. The reason for this is not clear, but it is presumed that the reaction between the surface of the silica fine particles and the silane coupling agent occurs more strongly when the amount of impurities is reduced to a predetermined amount or less.

Examples of the silane coupling agent required for the surface treatment of silica fine particles include 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropyltriethoxysilane, 3-acryloxypropyltrimethoxysilane, and 3-acryloxypropyltriethoxysilane. , 3-methacryloxypropylmethyldimethoxysilane, 3-methacryloxypropylmethyldiethoxysilane, 2-methacryloxypropyltrimethoxysilane, 2-methacryloxypropyltriethoxysilane, N-2 (aminoethyl) γ-aminopropylmethyl Examples thereof include dimethoxysilane, N-2 (aminoethyl) γ-aminopropyltrimethoxysilane, and N-2 (aminoethyl) γ-aminopropyltriethoxysilane.

The amount of the silane coupling agent treated on the silica fine particles is preferably in the range of 1 to 50% by weight, particularly 2 to 30% by weight, based on the silica fine particles. If the amount of the silane coupling agent treated on the silica fine particles is less than 1% by weight, the affinity of the silica fine particles with the ionizing radiation curable resin composition binder becomes insufficient. On the other hand, if it exceeds 50% by weight, a large amount of free silane coupling agent that has not been used for treating silica fine particles is present, so that the coating film becomes hard, the resilience to external impact is lowered, and it becomes brittle and cracks. And scratches increase.

The method for treating the silane coupling agent on the silica fine particles is not particularly limited as long as the dispersibility in the organic solvent and the affinity with the ionizing radiation curable resin composition can be improved. It can be processed by the method of. For example, the surface treatment of silica fine particles can be performed by adding a predetermined amount of a silane coupling agent to the dispersion liquid of silica particles and, if necessary, treating with acid or alkali or heat treatment.

In the present invention, not all silane coupling agents are introduced into the surface of the silica fine particles, and may be present alone or as a condensate in the coating liquid. Since the silane coupling agent has an excellent affinity with the binder component and the silica fine particles, the silica fine particles can be stably dispersed in the coating liquid. Further, since the silane coupling agent is taken into the membrane and acts as a cross-linking agent when cured by ionizing radiation or heating, the total amount of the silane coupling agent is compared with the case where the entire amount of the silane coupling agent is introduced into the surface of the silica fine particles. The performance of the coating film is improved.

The low refractive index layer constituting the antireflection laminate according to the present invention contains 70 to 250 parts by weight, preferably 80 to 220 parts by weight, of the surface-treated silica fine particles with respect to 100 parts by weight of the ionizing radiation curable resin composition. More preferably, it is contained in the range of 100 to 200 parts by weight. If it is 70 parts by weight or less, the desired refractive index cannot be obtained, and if it is 250 parts by weight or more, the amount of the binder for the silica fine particles decreases, and the coating film strength decreases.

3.<u style="single">Other ingredients</u> The low refractive index layer of the antireflection laminate according to the present invention may further contain a fluorine-based and / or silicon-based compound having compatibility with both the ionizing radiation curable resin composition and the silica fine particles. preferable. By including the fluorine-based compound and the like in this way, the surface of the coating film can be flattened, and slipperiness is effective in improving the antifouling property and scratch resistance required for the antireflection laminate. Can be given. The term "compatible" means that an amount of a fluorine-based and / or silicon compound is added to a coating film in which an ionizing radiation-curable resin composition or silica fine particles are present so that the above-mentioned addition effect can be confirmed. However, it means that the coating film has an affinity to the extent that a decrease in transparency due to cloudiness or an increase in haze cannot be confirmed.

In the present invention, it is further preferable that at least a part of the fluorine-based and / or silicon compound is fixed to the outermost surface of the coating film by forming a covalent bond with the ionizing radiation curable resin composition by a chemical reaction. .. As a result, slipperiness can be stably imparted, and the antifouling property and scratch resistance required for the antireflection laminate after commercialization can be maintained for a long period of time.

As the above-mentioned fluorine-based compound, C_dF_{2d + 1} A perfluoroalkyl group represented by (d is an integer from 1 to 21),-(CF₂CF₂)_gA perfluoroalkylene group represented by-(g is an integer from 1 to 50), or F-(-CF (CF)₃) CF₂O-)_e-CF (CF)₃) (Here, e is an integer from 1 to 50), as well as a perfluoroalkyl ether group, as well as CF.₂= CFCF₂CF₂-, (CF₃)₂C = C (C₂F₅)-, And ((CF₃)₂CF)₂C = C (CF)₃)-It is preferable to have a perfluoroalkenyl group exemplified by the above.

The structure of the fluorine-based compound is not particularly limited as long as it is a compound containing the above functional groups. For example, a polymer of a fluorine-containing monomer or a copolymer of a fluorine-containing monomer and a non-fluorine monomer may be used. You can also. Among them, a fluorine-containing polymer segment composed of either a homopolymer of a fluorine-containing monomer or a copolymer of a fluorine-containing monomer and a non-fluorine monomer, and a non-fluorine-based polymer segment. A block copolymer or a graft copolymer composed of the above is preferably used. In such a copolymer, the fluorine-containing polymer segment mainly has a function of enhancing antifouling property and water-repellent oil-repellent property, while the non-fluorine-based polymer segment has compatibility with the binder component. Has an anchor function that enhances. Therefore, in the antireflection laminate using such a copolymer, it is difficult to remove these fluorine-based compounds even when the surface is repeatedly rubbed, and various performances such as antifouling property are maintained for a long period of time. Can be maintained.

The above-mentioned fluorine-based compound can be obtained as a commercially available product, and for example, NOF's Modiper F series, Dainippon Ink and Chemicals' Defenser MCF series, and the like are preferably used.

The above-mentioned fluorine-based or / and silicon-based compounds have the following general formulas,<chemistry num="1"><img file="JP2011237802A_D0001.tif" /></chemistry>(In the formula, Ra indicates an alkyl group having 1 to 20 carbon atoms such as a methyl group, and Rb is an unsubstituted or amino group, an epoxy group, a carboxyl group, a hydroxyl group, a perfluoroalkyl group, a perfluoroalkylene group, or a perfluoro group. It shows an alkyl group having 1 to 20 carbon atoms, an alkoxy group having 1 to 3 carbon atoms, or a polyether-modified group substituted with an alkyl ether group or a (meth) acryloyl group, and Ra and Rb are the same or different from each other. Also, m is an integer of 0 to 200 and n is an integer of 0 to 200.) It is preferable to have the structure shown by.

Polydimethylsilicone having a basic skeleton like the above general formula is generally known to have low surface tension and excellent water repellency and releasability, but various functional groups are introduced into the side chain or the terminal. By doing so, a further effect can be imparted. For example, reactivity can be imparted by introducing an amino group, epoxy group, carboxyl group, hydroxyl group, (meth) acryloyl group, alkoxy group, etc., and a covalent bond is formed by a chemical reaction with the ionizing radiation curable resin composition. it can. Further, by introducing a perfluoroalkyl group, a perfluoroalkylene group, and a perfluoroalkyl ether group, oil resistance and lubricity can be imparted, and by introducing a polyether-modifying group, leveling property and lubricity can be imparted. Can be improved.

Such compounds can be obtained as commercially available products, for example, silicone oil FL100 having a fluoroalkyl group (manufactured by Shin-Etsu Chemical Co., Ltd.) and polyether-modified silicone oil TSF4460 (trade name, manufactured by GE Toshiba Silicone Co., Ltd.). ) Etc., various modified silicone oils can be obtained according to the purpose.

Further, as a preferred embodiment of the present invention, the fluorine-based or / and silicon-based compounds have the following general formulas. Ra_nSiX_4-n(In the formula, Ra represents a hydrocarbon group having 3 to 1000 carbon atoms including a perfluoroalkyl group, a perfluoroalkylene group, or a perfluoroalkyl ether group, and X is a carbon such as a methoxy group, an ethoxy group, or a propoxy group. It is an oxyalkoxy group such as an alkoxy group, a methoxymethoxy group, or a methoxyethoxy group of the number 1 to 3, or a hydrolyzable group such as a halogen group such as a chloro group, a bromo group or an iodo group, and they are the same but different. Also, n indicates an integer from 1 to 3.) It may have the structure shown by.

By including such a hydrolyzable group, it is easy to form a covalent bond or a hydrogen bond with a hydroxyl group of an inorganic component, in the present invention, a silica component, and there is an effect that adhesion can be maintained.

Specific examples of such a compound include fluoroalkylsilanes such as TSL8257 (manufactured by GE Toshiba Silicone Co., Ltd.).

The content of the fluorine-based and / or silicon-based compound is preferably 0.01 to 10% by weight, preferably 0.1 to 3.0% by weight, based on the total weight of the ionizing radiation curable resin composition and the silica fine particles. If the content is less than 0.01% by weight, sufficient antifouling property and slipperiness cannot be imparted to the antireflection laminate, and if it exceeds 10% by weight, the strength of the coating film is extremely lowered.

These fluorine-based compounds and silicon-based compounds may be used alone or in combination of two or more, depending on the degree of the expected effect. By appropriately combining these compounds, various properties such as antifouling property, water and oil repellency, slipperiness, scratch resistance, durability, and leveling property can be adjusted, and the desired function can be exhibited.

The low refractive index layer constituting the antireflection laminate according to the present invention contains the above-mentioned ionizing radiation-curable resin composition component and the above-mentioned surface-treated silica fine particle component as essential components, and preferably the above-mentioned fluorine-based and / / Alternatively, it contains a silicon compound, but may also contain a binder component other than the above-mentioned ionizing radiation curable resin composition component, if necessary. Further, the coating liquid for forming a low refractive index layer contains a solvent, a polymerization initiator, a curing agent, a cross-linking agent, an ultraviolet blocking agent, an ultraviolet absorber, a surface conditioner (leveling agent), or other components. You may be.

The polymerization initiator is not always necessary in the present invention. However, when the ionizing radiation curable group of the ionizing radiation curable resin composition component, the surface-treated silica fine particle component, and other binder component which is an optional component is unlikely to cause a direct polymerization reaction by ionizing radiation irradiation, the binder It is preferable to use an appropriate initiator according to the component and the reaction type of the silica fine particles.

For example, when the ionizing radiation curable group of the ionizing radiation curable resin composition component is a (meth) acryloyl group, a photoradical polymerization initiator is used. Examples of the photoradical polymerization initiator include acetophenones, benzophenones, ketals, anthraquinones, thioxanthones, azo compounds, peroxides, 2,3-dialkyldione compounds, disulfide compounds, thiuram compounds, and fluorocarbons. Amine compounds and the like are used. More specifically, 1-hydroxy-cyclohexyl-phenyl-ketone, 2-methyl-1 [4- (methylthio) phenyl] -2-morpholinopropan-1-one, benzyldimethylketone, 1- (4-dodecyl). Phenyl) -2-hydroxy-2-methylpropan-1-one, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 1- (4-isopropylphenyl) -2-hydroxy-2-methylpropane Examples thereof include -1-one and benzophenone. Among these, 1-hydroxy-cyclohexyl-phenyl-ketone and 2-methyl-1 [4- (methylthio) phenyl] -2-morpholinopropan-1-one are polymerized by irradiation with ionizing radiation even in a small amount. It is preferably used in the present invention because it initiates and accelerates the reaction. These can be used alone or in combination of both. These may be commercially available, for example, 1-hydroxy-cyclohexyl-phenyl-ketone can be obtained from Ciba Speciality Chemicals Co., Ltd. under the trade name of Irgacure 184.

When a photoradical polymerization initiator is used, the photoradical polymerization initiator is usually mixed in a ratio of 3 to 15 parts by weight with respect to a total of 100 parts by weight of the binder component mainly composed of the ionizing radiation curable resin composition. To do.

The curing agent is an unreacted hydrogen bond forming group contained in a part of the ionizing radiation curable resin composition, a silanol group existing on the surface of the surface-treated silica fine particles, a silane coupling agent used for the surface treatment, and a condensate thereof. It is blended to promote the thermosetting reaction of parts and the like.

When the thermosetting polar group is a hydroxyl group, the curing agent is usually a compound having a basic group such as methylol melamine, or a compound having a hydrolyzable group that generates a hydroxyl group by hydrolysis of a metal alkoxide or the like. Is used. Amine, nitrile, amide, and isocyanate group are preferably used as the basic group, and an alkoxy group is preferably used as the hydrolyzable group. Especially in the latter case, the following general formula, AlR₃(In the formula, the residue R may be the same or different, halogen, alkyl, alkoxy, or acyloxy, or hydroxy with 10 or less carbon atoms, preferably 4 or less carbon atoms, and all or part of these groups are chelated. It may be replaced by a ligand.) The aluminum compound represented by (1) and / or a derivative thereof has good compatibility with the hydroxyl group and is particularly preferably used. The compound can be selected from aluminum compounds and / or oligomers and / or complexes derived from them, and aluminum salts of inorganic or organic acids.

Specific examples thereof include aluminum-sec-butoxide, aluminum-iso-propoxide, and complexes thereof with acetylacetone, ethyl acetoacetate, alkanolamines, glycols, and derivatives thereof. When a curing agent is used, the curing agent is usually added at a ratio of 0.05 to 30.0 parts by weight with respect to a total of 100 parts by weight of the binder component mainly composed of the ionizing radiation curable resin composition.

4.<u style="single">Composition for forming a low refractive index layer</u> The low refractive index layer composed of each of the above components is coated by dissolving each of the above components in a solvent to prepare a composition for forming a low refractive index layer, and dispersing the composition according to a general preparation method. It can be formed by preparing a liquid, applying the coating liquid to a base material, and drying the liquid. Hereinafter, a method for adjusting the solvent, a composition for forming a low refractive index layer, and a method for forming a coating film will be described.

(1) Solvent When a liquid ionizing radiation curable resin composition is used as a binder component in a relatively large amount, the monomer and / or oligomer in the composition can also function as a liquid medium, so that coating can be performed without using a solvent. It may be possible to prepare in a liquid state. Therefore, the solvent is not always required in the present invention. However, in many cases, a solvent is used to dissolve and disperse the solid component, adjust the concentration, and prepare a coating liquid having excellent coating suitability.

The solvent used for dissolving and dispersing the solid component of the low refractive index layer in the present invention is not particularly limited, and various organic solvents such as alcohols such as isopropyl alcohol, methanol and ethanol, methyl ethyl ketone, methyl isobutyl ketone and cyclohexanone are used. Ketones such as, ethyl acetate, butyl acetate and the like, aromatic hydrocarbons such as halogenated hydrocarbons, toluene and xylene, or mixtures thereof can be used.

As the solvent, it is preferable to use a ketone-based organic solvent. When the coating liquid is prepared using a ketone solvent, it can be easily and uniformly applied to the surface of the base material, and the solvent evaporates at an appropriate rate after coating to prevent uneven drying. A thin large-area coating film can be easily obtained.

In order to impart a function as an antiglare layer to the hard coat layer which is a support layer of the antireflection laminate, the surface of the hard coat layer is formed in a fine uneven shape, and a medium refractive index layer or a high refractive index layer is formed on the surface. A low index layer may be formed with or without layers. When the coating liquid is prepared using a ketone solvent, it is possible to uniformly coat such a finely uneven surface, and it is possible to prevent uneven coating.

As a ketone solvent, a single solvent consisting of one kind of ketone, a mixed solvent consisting of two or more kinds of ketones, and another solvent together with one kind or two or more kinds of ketones are contained and the properties as a ketone solvent are lost. You can use the one that does not exist. Preferably, a ketone solvent containing 70% by weight or more of the solvent, particularly 80% by weight or more, and one or more kinds of ketones is used.

Further, the amount of the solvent is appropriately adjusted so that each component can be uniformly dissolved and dispersed, the silica fine particles do not aggregate even if left after preparation, and the concentration is not too dilute at the time of coating. It is preferable to prepare a high-concentration coating liquid by reducing the amount of solvent added within the range in which this condition is satisfied. By doing so, it can be stored in a state where it does not take up a large volume, and can be diluted to an appropriate concentration and used during the coating operation. When the total amount of the solid content and the solvent is 100 parts by weight, the solvent is 50 to 95.5 parts by weight, more preferably 10 to 30 parts by weight, based on 0.5 to 50 parts by weight of the total solid content. By using the solvent in a proportion of 70 to 90 parts by weight, a composition having a low refractive index, which is particularly excellent in dispersion stability and suitable for long-term storage, can be obtained.

(2) Adjustment of composition A composition for forming a low refractive index layer can be prepared by mixing each of the above essential components and each desired component in any order. If the surface-treated silica fine particles have a colloidal shape, they can be mixed as they are. Further, if it is in the form of powder, a medium for forming a low refractive index layer can be obtained by adding a medium such as beads to the obtained mixture and appropriately dispersing the mixture with a paint shaker, a bead mill or the like.

(3) Formation of coating film In order to form a coating film using the composition for forming a low refractive index layer, a coating containing an ionizing radiation curable resin composition, surface-treated silica fine particles, a fluorine-based and / or silicon-based compound, and various additives. The working solution is applied to the surface of the object to be coated, dried, and then cured by irradiation with ionizing radiation and / or heating.

Examples of the method for applying the composition for forming a low refractive index layer include a spin coating method, a dip method, a spray method, a slide coating method, a bar coating method, a roll coater method, a meniscus coater method, a flexographic printing method, and a screen printing method. , Bead coater method, etc.

5.<u style="single">Base material</u> The base material constituting the antireflection laminate according to the present invention may be in the form of a plate or a film. Preferred substrates include, for example, triacetate cellulose (TAC), polyethylene terephthalate (PET), diacetyl cellulose, acetate butyrate cellulose, polyether sulphon, acrylic resin, polyurethane resin, polyester, polycarbonate, polysulfone, polyether, etc. Examples thereof include films formed of various resins such as trimethylpentene, polyetherketone, (meth) acrylonitrile, and cyclic polyolefin. The thickness of the base material is usually about 30 to 200 μm, preferably 50 to 200 μm.

Thermosetting is performed by applying the coating liquid of the composition for forming a low refractive index layer directly to the surface of the base material to be coated or through another layer such as a hard coat layer and drying it. Due to the action of the polar groups having properties, a coating film having excellent adhesion to the surface of the object to be coated can be obtained.

6.<u style="single">Anti-reflective laminate</u> Next, an antireflection laminate according to a preferred embodiment of the present invention will be described.

The antireflection laminate according to the present invention is a single-layer or multi-layer antireflection film obtained by laminating one or more layers (light-transmitting layers) having light transmittance and different refractive indexes from each other. One layer, especially a low refractive index layer, is formed by the above composition. In the present invention, the layer having the highest refractive index among the multilayer antireflection films is referred to as a "high refractive index layer", the layer having the lowest refractive index is referred to as a "low refractive index layer", and other layers are referred to. A layer having an intermediate refractive index is referred to as a "medium refractive index layer".

The refractive index of the coated surface itself and the refractive index of the coating film even if a single layer of the coating film made of the composition used in the present invention is provided on the surface covered by the antireflection laminate, for example, the display surface of the image display device. When the balance with is good, the antireflection effect can be obtained. Therefore, the antireflection laminate of the present invention may also function effectively as a single-layer antireflection laminate.

The antireflection laminate according to the present invention is particularly a display surface or a projection screen of an image display device such as a liquid crystal display (LCD), a cathode ray tube display (CRT), a plasma display panel (PDP), or an electroluminescence display (ELD). It is suitably used for forming at least one layer of a multilayer antireflection film that covers the surface of an image forming medium such as a low refractive index layer.

In the layer structure of the antireflection laminate according to the present invention, in order to obtain a desired antireflection effect, the low refractive index layer is used as the outermost layer, and the low refractive index layer alone, the high refractive index layer / low refractive index layer, and the medium refractive index are used. It may be any of a layer / a high refractive index layer / a low refractive index layer. The film thickness of all these layers is in the range of 0.05 to 0.15 μm, preferably 0.07 to 0.12 μm. When the film thickness is in the above range, a sufficient antireflection effect can be obtained.

The antireflection laminate may be provided directly on the base material or may be provided on the hard coat layer. In order to diffuse the light from the outside and reduce the glare, the surface of the hard coat layer may have an uneven shape. Further, when an antiglare layer (anti-glare layer) having a function of dispersing an inorganic or organic filler inside the hard coat layer and scattering light inside the hard coat layer is provided, reflection is performed on the antiglare layer. A preventive laminate may be provided.

Further, when it is necessary to impart antistatic property or electrostatic property, a conductive layer may be provided on the base film. Further, conductive particles may be contained in the hard coat layer. Furthermore, by dispersing conductive particles in a medium-refractive index layer or a high-refractive index layer having a refractive index in the range of 1.46 to 2.00, or by using an inorganic oxide fine particle itself having a high refractive index that has conductivity. Can also obtain the same effect.

Further, as long as the desired refractive index can be obtained, an antistatic agent composed of an organic component may be added directly to the low refractive index layer, or an antistatic layer may be added to the outermost surface of the low refractive index layer to affect the performance of the antireflection laminate. It can also be provided in the range of a film thickness of 30 nm or less that does not give.

Surface resistance is 10¹²It is desirable that it is Ω / or less, but 10¹²Even if it is Ω / or more, antistatic performance can be imparted by giving conductivity to any of the layers, and dust is less likely to adhere to the layer as compared with those having no conductivity. Hereinafter, each layer will be described in detail.

(1)<u style="single">Hard coat layer</u> The hard coat layer is formed using an ionizing radiation curable resin composition. In addition, in this specification, a "hard coat layer" means a layer which shows hardness of H or more in the pencil hardness test shown in JIS5600-5-4: 1999.

The ionizing radiation curable resin composition suitable for forming the hard coat layer is preferably one having an acrylate-based functional group, for example, a polyester resin having a relatively low molecular weight, a polyether resin, a polyether resin, or an acrylic. Di (meth) such as resin, epoxy resin, urethane resin, alkyd resin, spiroacetal resin, polybutadiene resin, polythiol polyether resin, polyhydric alcohol, ethylene glycol di (meth) acrylate, pentaerythritol di (meth) acrylate monostearate, etc. ) Acrylate; Trimethylol Propanetri (meth) acrylate, pentaerythritol Tri (meth) acrylate and other tri (meth) acrylate, pentaerythritol tetra (meth) acrylate derivative and dipentaerythritol penta (meth) acrylate and other polyfunctional (meth) acrylate ) Monomers such as polyfunctional compounds such as acrylate and oligomers such as epoxy acrylate and urethane acrylate can be used.

The photopolymerization initiator for the ionizing radiation curable resin composition is appropriately selected from those exemplified above and used.

The film thickness of the hard coat layer after curing is preferably in the range of 0.1 to 100 μm, preferably 0.8 to 20 μm. When the film thickness is 0.1 μm or less, sufficient hard coating performance cannot be obtained, and when the film thickness is 100 μm or more, it is easily cracked by an external impact.

Further, in the present invention, the hard coat layer made of the ionizing radiation curable resin composition may have the functions of a medium refractive index layer or a high refractive index layer as described below.

(2)<u style="single">Anti-glare layer</u> The antiglare layer is essentially composed of an ionizing radiation curable resin composition and resin beads having a refractive index of 1.40 to 1.60. By including the resin beads, it is possible to impart antiglare performance in addition to the hard coat property.

The ionizing radiation curable resin composition can be appropriately selected from those preferably used for the above-mentioned hard coat layer.

The reason for limiting the refractive index of the resin beads to the above range is as follows. That is, the refractive index of the ionized radiation curable resin, particularly the acrylate or methacrylate resin, is usually 1.45 to 1.55, and by selecting resin beads having a refractive index as close as possible to the refractive index of the ionized radiation curable resin, the coating film is coated. This is because the anti-glare property can be improved without impairing the transparency of the plastic.

Examples of resin beads having a refractive index close to that of an ionized radiation curable resin include polymethylmethacrylate beads (1.49), polycarbonate beads (1.58), polystyrene beads (1.50), polyacrylic styrene beads (1.57), and poly. There are vinyl chloride beads (1.54) and the like, but if the refractive index is within the above range, other ones can be used.

The particle size of these resin beads is preferably 3 to 8 μm, and is 2 to 10 parts by weight, usually about 4 parts by weight, based on 100 parts by weight of the resin. In the coating liquid in which the resin beads are mixed in the resin, it is necessary to stir and disperse the resin beads precipitated at the time of use. In order to eliminate such inconvenience, silica beads having a particle size of 0.5 μm or less, preferably 0.1 to 0.25 μm may be added to the coating liquid as a sedimentation inhibitor. The more these silica beads are added, the more effective it is in preventing the organic filler from settling, but it adversely affects the transparency of the coating film. Therefore, it is preferable to add silica beads in a range that does not impair the transparency of the coating film and can prevent sedimentation, that is, less than 0.1 part by weight with respect to 100 parts by weight of the resin.

The film thickness of the antiglare layer after curing is preferably in the range of 0.1 to 100 μm, preferably 0.8 to 20 μm. When the film thickness is 0.1 μm or less, sufficient hard coating performance cannot be obtained, and when the film thickness is 100 μm or more, it is easily cracked by an external impact.

(3)<u style="single">Antistatic layer</u> The antireflection laminate according to the present invention suppresses the generation of static electricity to prevent the adhesion of dust, and prevents static electricity from the outside when it is incorporated into a liquid crystal display or the like. Layers may be formed. The performance of the antistatic layer in this case is that the surface resistance after forming the antireflection laminate is 10.¹²It is preferably Ω / or less. But 10¹²Even if it is Ω / or more, dust adhesion can be suppressed as compared with the one without the antistatic layer.

Examples of the antistatic agent contained in the resin composition for forming an antistatic layer include various cationic antistatic agents having a cationic group such as a quaternary ammonium salt, a pyridinium salt, and a primary to tertiary amino group. Anionic antistatic agents having anionic groups such as sulfonic acid bases, sulfate ester bases, phosphoric acid ester bases, and phosphonic acid bases, amphoteric antistatic agents such as amino acid bases and aminosulfate ester bases, amino alcohol type, glycerin type, Nonionic antistatic agents such as polyethylene glycols, various surfactant-type antistatic agents such as organic metal compounds such as tin and titanium alkoxides and metal chelate compounds such as their acetylacetonate salts, as well as the above. Examples thereof include a high molecular weight antistatic agent obtained by increasing the amount of the antistatic agent as described above. In addition, organic metal compounds such as a tertiary amino group, a quaternary ammonium group, a monomer or oligomer having a metal chelating portion and polymerizable by ionizing radiation, and a coupling agent having a functional group polymerizable by ionizing radiation. Polymerizable antistatic agents such as these can also be used.

Other antistatic agents contained in the antistatic layer forming resin composition include ultrafine particles having a particle size of 100 nm or less, such as tin oxide, tin-doped indium oxide (ITO), antimony-doped tin oxide (ATO), and indium-doped zinc oxide. (AZO), antimon oxide, indium oxide and the like can be used. In particular, when the particle size is 100 nm or less, which is equal to or less than the wavelength of visible light, the film becomes transparent after film formation, and the transparency of the antireflection film is not impaired.

By mixing the antistatic agent in the coating liquid that forms the hard coat layer and the antiglare layer, the two properties of antistatic performance and hard coat performance, or the two properties of antistatic performance and antiglare performance. A coating film having improved properties can be obtained at the same time.

(4)<u style="single">High-refractive index layer and medium-refractive index layer (refractive index layer in the range of 1.46 to 2.00)</u> The high-refractive index layer and the medium-refractive index layer of the present invention are mainly ionized radiation-curable resin, ultrafine zinc oxide having a particle diameter of 100 nm or less (refractive index 1.90, the following numerical values indicate the refractive index), and titania. Consists of one or more fine particles selected from the group consisting of (2.3 ~ 2.7), ceria (1.95), tin-doped indium oxide (1.95), antimon-doped tin oxide (1.80), itria (1.87), and zirconia (2.0). Will be done. The fine particles preferably have a higher refractive index than the ionizing radiation curable resin binder. The refractive index is determined by the content of fine particles in the refractive index layer. That is, since the refractive index increases as the content of the fine particles increases, the refractive index can be freely controlled in the range of 1.46 to 2.00 by changing the composition ratio of the ionizing radiation curable resin and the fine particles.

As the ionizing radiation curable resin, the photopolymerization initiator, and various additives, the same ones as described above can be used, and the same method as described above can be used as the forming method.

Further, the medium refractive index layer and the high refractive index layer are deposited with an inorganic oxide having a high refractive index such as titanium oxide or zirconium oxide formed by a vapor deposition method such as chemical vapor deposition (CVD) or physical vapor deposition (PVD). It can be a film or a coating film in which inorganic oxide fine particles having a high refractive index such as titanium oxide are dispersed. As the medium refractive index layer, a light transmitting layer having a refractive index in the range of 1.46 to 1.80 can be used, and as the high refractive index layer, a light transmitting layer having a refractive index of 1.65 or more can be used.

(5)<u style="single">Anti-reflective film</u> The antireflection film has a structure in which one or more light-transmitting layers having light-transmitting properties and different refractive indexes are laminated on one side or both sides of a light-transmitting base film, directly or via another layer. At least one of the light transmitting layers is formed of the antireflection laminate according to the present invention. The base film and the light-transmitting layer need to have a light-transmitting property that can be used as a material for the antireflection film, and those as close to transparent as possible are preferable.

A hard coat layer may be provided on the antireflection film for the purpose of imparting performance such as scratch resistance and strength. Alternatively, an antiglare layer may be provided as another layer for the purpose of imparting antiglare performance to the antireflection film.

FIG. 1 schematically shows a cross section of an example of an antireflection film made of an antireflection laminate according to the present invention. The antireflection film 1 is provided with a high refractive index layer 3 on one surface side of a base film 2 having light transmittance, and further, a low refractive index used in the present invention is provided on the high refractive index layer 3. The low refractive index layer 4 formed by applying the composition is provided. Further, a hard coat layer 5 is provided between the base film 2 and the high refractive index layer 3. In this embodiment, the light-transmitting layers having different refractive indexes are composed of only two layers, a high-refractive index layer and a low-refractive index layer. More than one layer may be provided. When the light transmitting layer or the like is provided in this way, the medium refractive index layer formed by applying the composition for forming a low refractive index layer used in the present invention is further added to the low refractive index layer 4. May be provided.

Examples and comparative examples of the present invention are shown below, but the scope of the present invention is not limited thereto.

1.<u style="single">Preparation of silica fine particles I</u> Average particle size 5nm, SiO₂A mixture of 100 g of silica sol having a concentration of 20% by weight and 1900 g of pure water was heated to 80 ° C. to prepare a reaction stock solution. The pH of this reaction stock solution was 10.5. In this mother liquor, SiO₂As 1.17% by weight sodium silicate aqueous solution 9000 g and Al₂O₃As a result, 9000 g of 0.83 wt% sodium aluminate aqueous solution was added at the same time. Meanwhile, the mixed solution was kept at 80 ° C. Immediately after the addition, the pH of the mixed solution rose to 12.5 and remained almost unchanged thereafter. After the addition is completed, the mixed solution is cooled to room temperature, washed with an ultrafiltration membrane, and SiO with a solid content concentration of 20% by weight.₂ Al₂O₃A nuclear particle dispersion was prepared.

To 500 g of the obtained nuclear particle dispersion, 1700 g of pure water was added and heated to 98 ° C., and while maintaining the temperature, the sodium silicate aqueous solution was dealkalised with a cation exchange resin to obtain a silicic acid solution (SiO).₂Concentration 3.5% by weight) 3000 g was added. In this way, a dispersion of nuclear particles on which the first silica coating layer was formed was obtained.

This dispersion was washed with an ultrafiltration membrane to obtain a dispersion having a solid content concentration of 13% by weight of silica-coated nuclear particles. 1125 g of pure water was added to 500 g of this dispersion, and concentrated hydrochloric acid (35.5%) was added dropwise until the dispersion reached pH 1.0 to perform dealumination treatment. Next, 10 L of a hydrochloric acid aqueous solution having a pH of 3 and 5 L of pure water were added to this dispersion, and the solution was filtered through an ultrafiltration membrane to separate the dissolved aluminum salt. In this way, SiO in which some of the constituents of the nuclear particles have been removed.₂ Al₂O₃A dispersion of porous particles was prepared.

A mixture of 1500 g of the above-mentioned porous particle dispersion, 500 g of pure water, 1750 g of ethanol, and 626 g of 28% ampinian water is heated to 35 ° C., and then ethyl silicate (SiO) is added to the mixture.₂By adding 104 g (28% by weight) and coating the surface of the porous particles on which the silica coating layer was formed with the hydrolyzed polycondensate of ethyl silicate, the second silica coating layer was formed on the first silica coating layer. The formed porous fine particle dispersion was obtained.

This silica fine particle dispersion was concentrated to a solid content concentration of 5% by weight using an evaporator, and ammonia water having a concentration of 15% by weight was added to adjust the pH to 10.

This dispersion is heat-treated at 180 ° C for 2 hours in an autoclave, cooled to room temperature, and ion-exchanged for 3 hours using 400 g of a cation exchange resin (Diaion SK1B, manufactured by Mitsubishi Chemical Corporation). Next, ion exchange was performed for 3 hours using 200 g of an anion exchange resin (Diaion SA20A, manufactured by Mitsubishi Chemical Corporation), and then washed to obtain an aqueous dispersion of silica-based fine particles having a solid content concentration of 20% by weight. ..

At this time, Na in the aqueous dispersion of silica-based fine particles₂O content and NH₃The contents were 7 ppm and 1600 ppm, respectively, per silica fine particles.

Subsequently, a dispersion of silica-based fine particles I having a solid content concentration of 20% by weight was prepared by substituting the solvent with isopropyl alcohol using an ultrafiltration membrane.

2.<u style="single">Preparation of silica fine particles II</u> Average particle size 5nm, SiO₂A mixture of 100 g of silica sol having a concentration of 20% by weight and 1900 g of pure water was heated to 80 ° C. to prepare a reaction stock solution. The pH of this reaction stock solution was 10.5. In this mother liquor, SiO₂As 1.17% by weight sodium silicate aqueous solution 9000 g and Al₂O₃As a result, 9000 g of 0.83 wt% sodium aluminate aqueous solution was added at the same time. Meanwhile, the mixed solution was kept at 80 ° C. Immediately after the addition, the pH of the mixed solution rose to 12.5 and remained almost unchanged thereafter. After the addition is completed, the mixed solution is cooled to room temperature, washed with an ultrafiltration membrane, and SiO with a solid content concentration of 20% by weight.₂ Al₂O₃A nuclear particle dispersion was prepared.

To 500 g of the obtained nuclear particle dispersion, 1700 g of pure water was added and heated to 98 ° C., and while maintaining the temperature, the sodium silicate aqueous solution was dealkalised with a cation exchange resin to obtain a silicic acid solution (SiO).₂Concentration 3.5% by weight) 3000 g was added. In this way, a dispersion of nuclear particles on which the first silica coating layer was formed was obtained.

This dispersion was washed with an ultrafiltration membrane to obtain a dispersion having a solid content concentration of 13% by weight of silica-coated nuclear particles. 1125 g of pure water was added to 500 g of this dispersion, and concentrated hydrochloric acid (35.5%) was added dropwise until the dispersion reached pH 1.0 to perform dealumination treatment. Next, 10 L of a hydrochloric acid aqueous solution having a pH of 3 and 5 L of pure water were added to this dispersion, and the solution was filtered through an ultrafiltration membrane to separate the dissolved aluminum salt. In this way, SiO in which some of the constituents of the nuclear particles have been removed.₂ Al₂O₃A dispersion of porous particles was prepared.

A mixture of 1500 g of the above porous particle dispersion, 500 g of pure water, 1750 g of ethanol, and 626 g of 28% aqueous ammonia is heated to 35 ° C, and then ethyl silicate (SiO) is added to the mixture.₂By adding 104 g (28% by weight) and coating the surface of the porous particles on which the silica coating layer was formed with the hydrolyzed polycondensate of ethyl silicate, the second silica coating layer was formed on the first silica coating layer. The formed porous fine particle dispersion was obtained.

This silica fine particle dispersion was concentrated to a solid content concentration of 5% by weight using an evaporator, and ammonia water having a concentration of 15% by weight was added to adjust the pH to 10.

Next, this dispersion is heat-treated at 180 ° C for 2 hours in an autoclave, cooled to room temperature, and ion-exchanged for 3 hours using 400 g of a cation exchange resin (Diaion SK1B, manufactured by Mitsubishi Chemical Corporation). Then, ion exchange was performed for 3 hours using 200 g of anion exchange resin (Diaion SA20A, manufactured by Mitsubishi Chemical Corporation), and then 200 g of cation exchange resin (Diaion SK1B manufactured by Mitsubishi Chemical Co., Ltd.) was added. After ion exchange at 80 ° C. for 3 hours, the mixture was washed to obtain an aqueous dispersion of silica-based fine particles having a solid content concentration of 20% by weight.

At this time, Na in the aqueous dispersion of silica-based fine particles₂O content and NH₃The contents were 6 ppm and 1200 ppm, respectively, per silica fine particles.

Next, the obtained silica-based fine particle dispersion was hydrothermally treated at 150 ° C. for 11 hours, and then washed with an ultrafiltration membrane while adding 5 L of pure water to obtain silica-based fine particles having a solid content concentration of 20% by weight. Water dispersion was obtained.

At this time, Na in the aqueous dispersion of silica-based fine particles₂O content and NH₃The contents were 0.5 ppm and 600 ppm, respectively, per silica fine particle. Subsequently, the solvent was replaced with isopropyl alcohol using an ultrafiltration membrane to prepare a dispersion of silica-based fine particles II having a solid content concentration of 20% by weight.

Further, the surface treatment of the obtained silica fine particles I and II was carried out by the following method.

1. Surface treatment A (treatment amount: 5% by weight) The dispersions of silica fine particles I and II obtained above were subjected to solvent substitution from isopropyl alcohol to methyl isobutyl ketone using a rotary evaporator to obtain a dispersion of 20% by weight of silica fine particles. Methyl isobutyl of 20% by weight of hollow silica fine particles surface-treated by adding 5% by weight of 3-methacryloxypropylmethyldimethoxysilane to 100% by weight of this methyl isobutyl ketone dispersion and heat-treating at 50 ° C. for 1 hour. Ketone dispersions IA and IIA were obtained.

2. Surface treatment B (treatment amount: 10% by weight) Methyl isobutyl ketone dispersions IB and IIB having 20% by weight of surface-treated hollow silica fine particles were obtained in the same manner as in Surface Treatment A except that 10% by weight of 3-methacryloxypropylmethyldimethoxysilane was added.

3. Surface treatment C (treatment amount: 0.9% by weight) Methyl isobutyl ketone dispersion IC and IIC having 20% by weight of surface-treated hollow silica fine particles were obtained in the same manner as in Surface Treatment A except that 0.9% by weight of 3-methacryloxypropylmethyldimethoxysilane was added.

Example 1<u style="single">Preparation of composition for forming a low refractive index layer</u> A composition for forming a low refractive index layer was prepared by mixing the components having the following compositions. Surface-treated hollow silica sol (hollow silica fine particle dispersion IA) 12.85 parts by weight Pentaerythritol triacrylate (PETA) 1.43 parts by weight Irgacure 907 (trade name, manufactured by Chivas Specialty Chemicals) 0.1 parts by weight F3035 (trade name, manufactured by NOF CORPORATION) 0.4 parts by weight Methyl Isobutyl Ketone 85.22 parts by weight<u style="single">Preparation of composition for forming a hard coat layer</u> A composition for forming a hard coat layer was prepared by blending the components having the following compositions. Pentaerythritol triacrylate (PETA) 5.0 parts by mass Irgacure 184 (trade name, manufactured by Chivas Specialty Chemicals) 0.25 parts by mass Methyl isobutyl ketone 94.75 parts by mass<u style="single">Fabrication / Hard coat layer / Low refractive index layer film</u> A composition for forming a hard coat layer having the above composition is bar-coated on a triacetate cellulose (TAC) film having a thickness of 80 μm, and after removing the solvent by drying, an ultraviolet irradiation device (Fusion UV System Japan Co., Ltd., light source H pulp) ), Irradiation dose 100mJ / cm²The hard coat layer was cured by irradiating with ultraviolet rays to obtain a base material / hard coat layer film having a hard coat layer having a film thickness of about 5 μm.

The above composition for forming a low refractive index layer is bar-coated on the obtained base material / hard coat layer film, and the solvent is removed by drying, and then an ultraviolet irradiation device (Fusion UV System Japan Co., Ltd., Using the light source H bulb), the irradiation dose is 200 mJ / cm.²The coating film was cured by irradiating with ultraviolet rays to obtain a laminate of a base material / hard coat layer / low refractive index layer.

Example 2 The composition for forming a low refractive index layer used in Example 1 was formed in the same manner as in Example 1 except that the composition was changed as follows, and a hard coat layer and a low refractive index layer were formed to form Example 2. Was obtained.

Surface-treated hollow silica sol (hollow silica fine particle dispersion IB) 12.85 parts by weight Pentaerythritol triacrylate (PETA) 1.43 parts by weight Irgacure 907 (trade name, manufactured by Chivas Specialty Chemicals) 0.1 parts by weight F3035 (trade name, manufactured by NOF CORPORATION) 0.4 parts by weight Methyl Isobutyl Ketone 85.22 parts by weight Example 3 The composition for forming a low refractive index layer used in Example 1 was formed in the same manner as in Example 1 except that the composition was changed as follows to form a hard coat layer and a low refractive index layer in Example 3. Was obtained.

Surface-treated hollow silica sol (hollow silica fine particle dispersion IB) 12.85 parts by weight Dipentaerythritol hexaacrylate (DPHA) 1.43 parts by weight Irgacure 907 (trade name, manufactured by Chivas Specialty Chemicals) 0.1 parts by weight F3035 (trade name, manufactured by NOF CORPORATION) 0.4 parts by weight Methyl Isobutyl Ketone 85.22 parts by weight Example 4 The composition for forming a low refractive index layer used in Example 1 was formed in the same manner as in Example 1 except that the composition was changed as follows, and a hard coat layer and a low refractive index layer were formed to form Example 4. Was obtained.

Surface-treated hollow silica sol (hollow silica fine particle dispersion IB) 12.85 parts by weight Pentaerythritol triacrylate (PETA) 1.43 parts by weight Irgacure 907 (trade name, manufactured by Chivas Specialty Chemicals) 0.1 parts by weight TSF4460 (trade name, manufactured by GE Toshiba Silicone Co., Ltd.) 0.12 parts by weight Methyl isobutyl ketone 85.5 parts by weight Example 5 The composition for forming a low refractive index layer used in Example 1 was formed in the same manner as in Example 1 except that the composition was changed as follows to form a hard coat layer and a low refractive index layer in Example 5. Was obtained.

Surface-treated hollow silica sol (hollow silica fine particle dispersion IIA) 12.85 parts by weight Pentaerythritol triacrylate (PETA) 1.43 parts by weight Irgacure 907 (trade name, manufactured by Chivas Specialty Chemicals) 0.1 parts by weight F3035 (trade name, manufactured by NOF CORPORATION) 0.4 parts by weight Methyl Isobutyl Ketone 85.22 parts by weight Example 6 The composition for forming a low refractive index layer used in Example 1 was formed in the same manner as in Example 1 except that the composition was changed as follows, and a hard coat layer and a low refractive index layer were formed to form Example 6. Was obtained.

Surface-treated hollow silica sol (hollow silica fine particle dispersion IIB) 12.85 parts by weight Pentaerythritol triacrylate (PETA) 1.43 parts by weight Irgacure 907 (trade name, manufactured by Chivas Specialty Chemicals) 0.1 parts by weight F3035 (trade name, manufactured by NOF CORPORATION) 0.4 parts by weight Methyl Isobutyl Ketone 85.22 parts by weight Example 7<u style="single">Preparation of composition for forming antistatic layer</u> A composition for forming an antistatic layer was prepared by mixing the components having the following compositions. Antimony-doped tin oxide dispersion (Solid content 45%, Pertron C-4456S-7: Product name, manufactured by Japan Pernox) 25 parts by weight HDDA (KS-HDDA: Product name, manufactured by Nippon Kayaku 10.5 parts by weight Irgacure 184 (trade name, manufactured by Ciba Specialty Chemicals) 0.84 parts by weight Butyl acetate 76.5 parts by weight Cyclohexanone 32.8 parts by weight<u style="single">Fabrication of laminate (base material / antistatic layer / hard coat layer / low refractive index layer)</u> The composition for forming an antistatic layer having the above composition is bar-coated on a TAC film, the solvent is removed by drying, and then an irradiation dose of about 20 mJ / cm is used using an ultraviolet irradiation device.²The antistatic layer was cured by irradiating with ultraviolet rays to prepare an antistatic layer having a film thickness of about 1 μm.

Next, a hard coat layer and a low refractive index layer were formed on the obtained base material / antistatic layer film in the same manner as in Example 2 to obtain a laminate of Example 7.

<u style="single">Evaluation of antistatic performance</u> (1) Dust wiping test When dust of tissue paper was sprinkled on the obtained laminate 5 and the surface was lightly wiped with a bencot, the dust was easily wiped off. (2) Charge attenuation measurement The charge attenuation of the laminate 5 obtained above and the base material / hard coat layer film without the antistatic layer was measured using an Honest meter (manufactured by Sind Electrostatic Co., Ltd.). The measurement conditions are shown below. Applied voltage: + 10kV Probe position: 20 cm Measurement time: 5 minutes The results are shown below. The effect of the antistatic layer was confirmed.<tables num="1"><img file="JP2011237802A_D0002.tif" /></tables>

Example 8<u style="single">Preparation of composition for forming a medium refractive index antistatic layer</u> A composition for forming an antistatic layer was prepared by mixing the components having the following compositions.

Indium oxide dispersion (Solid content 35%, EI-3: Product name, manufactured by Dai Nippon Toryo Co., Ltd.) 14.3 Parts by weight Isopropyl alcohol 85.7 parts by weight<u style="single">Fabrication of laminate (base material / hard coat layer / antistatic layer / low refractive index layer)</u> A hard coat layer was formed on a PET film having a thickness of 100 μm in the same manner as in Example 1. Next, the composition for forming an antistatic layer having the above composition is bar-coated, the solvent is removed by drying, and then the irradiation dose is 100 mJ / cm using an ultraviolet irradiation device.² The coating film was cured by irradiating with ultraviolet rays to obtain an antistatic layer having a film thickness of about 80 nm and a refractive index of 1.65.

A low refractive index layer was formed on the obtained laminate (base material / hard coat layer / antistatic layer) in the same manner as in Example 2 to obtain the laminate of Example 8.

<u style="single">Evaluation of antistatic performance</u> (1) Dust wiping test When dust of tissue paper was sprinkled on the obtained laminate 5 and the surface was lightly wiped with a bencot, the dust was easily wiped off.

(2) Surface resistivity measurement For the measurement of the surface resistivity (Ω / ) of the obtained coating film, the outermost surface of the laminate was measured at an applied voltage of 100 V using a high resistivity meter (Hiresta UP, manufactured by Mitsubishi Chemical Corporation). It was. As a result, 2.0 × 10⁹It was (Ω / ).

Example 9<u style="single">Preparation of antiglare layer forming composition</u> A composition for forming an antiglare layer was prepared by mixing the components having the following compositions. Dipentaerythritol hexaacrylate (DPHA) 25 parts by weight Styrene beads (particle size 3.5 μm) 6 parts by weight 50 parts by weight of toluene Irgacure 184 (trade name, manufactured by Chivas Specialty Chemicals) 2 parts by weight<u style="single">Fabrication of laminate (base material / antiglare layer / low refractive index layer)</u> The composition for forming an antiglare layer having the above composition is bar-coated on a TAC film, the solvent is removed by drying, and then an irradiation dose of 100 mJ / cm is used using an ultraviolet irradiation device.²The antiglare layer was cured by irradiating with ultraviolet rays to obtain a base material / antiglare layer film having an antiglare layer having a film thickness of about 4 μm.

Next, a low refractive index layer was formed on the obtained base material / antiglare layer film in the same manner as in Example 2 to obtain a laminate of Example 9.

Example 10<u style="single">Preparation of composition for forming medium refractive index hard coat layer</u> A composition for forming a medium refractive index hard coat layer having a refractive index of 1.63 was prepared by mixing the components having the following compositions. KZ7973 (trade name, manufactured by JSR Corporation) 47 parts by weight Pentaerythritol triacrylate (PETA) 5 parts by weight Irgacure 184 (trade name, manufactured by Chivas Specialty Chemicals) 1 part by weight Cyclohexanone 12 parts by weight<u style="single">Fabrication of laminate (base material / medium refractive index hard coat layer / low refractive index layer)</u> The composition for forming a medium refractive index hard coat layer having the above composition is bar-coated on a TAC film, the solvent is removed by drying, and then an irradiation dose of 100 mJ / cm is used using an ultraviolet irradiation device.²The coating film was cured in 1 to obtain a base material / medium refractive index hard coat layer film having a medium refractive index hard coat layer having a thickness of about 5 μm.

Next, a low refractive index layer was formed on the obtained base material / medium refractive index hard coat layer film in the same manner as in Example 2 to obtain a laminate of Example 10.

Example 11<u style="single">Preparation of antifouling layer forming composition</u> A composition for forming an antifouling layer was prepared by mixing the components having the following compositions.

KP-801M (trade name, manufactured by Shin-Etsu Chemical Co., Ltd.) 6.7 parts by weight FC-40 (trade name, manufactured by Sumitomo 3M Ltd.) 93.3 parts by weight<u style="single">Preparation of laminate (base material / hard coat layer / low refractive index layer / antifouling layer)</u> A hard coat layer and a low refractive index layer were formed on the base material in the same manner as in Example 2. Then, the antifouling layer forming composition having the above composition was bar-coated and heat-cured at 70 ° C. for 4 minutes to obtain a laminate of Example 11.

Example 12<u style="single">Preparation of composition for forming high refractive index layer</u> The following components were mixed to prepare a composition for forming a high refractive index layer having a refractive index of 1.90.

Rutile type titanium oxide (trade name: MT-500HDM, manufactured by TAYCA) 10 parts by weight Disperbyk163 (trade name, made by Big Chemie Japan) 2 parts by weight Pentaerythritol triacrylate (PETA) 4 parts by weight Irgacure 184 (trade name, manufactured by Chivas Specialty Chemicals) 0.2 parts by weight Methyl isobutyl ketone 37.3 parts by weight<u style="single">Preparation of composition for forming a medium refractive index layer</u> To 10 parts by weight of the titania dispersion having a refractive index of 1.90, 2.5 parts by weight of dipentaerythritol pentaacrylic paste (SR399E: trade name, manufactured by Nippon Kayaku Co., Ltd.) was added to form a composition for forming a medium refractive index layer having a refractive index of 1.76. The thing was prepared.

<u style="single">Preparation of laminate (base material / hard coat layer / medium refractive index layer / high refractive index layer / low refractive index layer)</u> A composition for forming a medium refractive index layer having the above composition is bar-coated on a base material / hard coat layer film prepared in the same manner as in Example 1, the solvent is removed by drying, and then irradiation is performed using an ultraviolet irradiation device. Dose 100mJ / cm²The coating film was cured by irradiating with ultraviolet rays to obtain a medium refractive index layer having a film thickness of about 80 nm. Further, the composition for forming a high refractive index layer having the above composition was applied under the same conditions to obtain a high refractive index layer having a film thickness of about 60 nm. A low refractive index layer was formed on the obtained laminated body (base material / hard coat layer / medium refractive index layer / high refractive index layer) in the same manner as in Example 2 to obtain the laminated body of Example 12. ..

Example 13<u style="single">Preparation of composition for forming high refractive index layer</u> The following components were mixed to prepare a composition for forming a high refractive index layer having a refractive index of 1.70. Rutile type titanium oxide (trade name: MT-500HDM, manufactured by TAYCA) 10 parts by weight Disperbyk163 (trade name, made by Big Chemie Japan) 2 parts by weight Pentaerythritol triacrylate (PETA) 7.5 parts by weight Irgacure 184 (trade name, manufactured by Chivas Specialty Chemicals) 0.2 parts by weight Methyl isobutyl ketone 37.3 parts by weight<u style="single">Fabrication of laminate (base material / hard coat layer / high refractive index layer / low refractive index layer)</u> A composition for forming a high refractive index layer having the above composition is bar-coated on a base material / hard coat layer film prepared in the same manner as in Example 1, the solvent is removed by drying, and then irradiation is performed using an ultraviolet irradiation device. Dose 100mJ / cm²The coating film was cured by irradiating with ultraviolet rays to obtain a high refractive index layer having a film thickness of about 80 nm. A low refractive index layer was formed on the obtained laminated body (base material / hard coat layer / high refractive index layer) in the same manner as in Example 2 to obtain the laminated body of Example 13.

Comparative example 1 A hard coat layer and a low refractive index layer were formed in the same manner as in Example 1 except that the composition for forming a low refractive index layer was changed as follows in Example 1, and the laminate of Comparative Example 1 was formed. Obtained.

Surface untreated hollow silica sol (dispersion of silica-based fine particles I) 12.85 parts by weight Pentaerythritol triacrylate (PETA) 1.43 parts by weight Irgacure 907 (trade name, manufactured by Chivas Specialty Chemicals) 0.1 parts by weight F3035 (trade name, manufactured by NOF CORPORATION) 0.4 parts by weight Methyl Isobutyl Ketone 85.22 parts by weight Comparative example 2 The composition for forming a low refractive index layer in Example 1 was formed in the same manner as in Example 1 except that the composition for forming a low refractive index layer was changed as follows, and a hard coat layer and a low refractive index layer were formed to form a laminate of Comparative Example 2. Got

Surface-treated hollow silica sol (hollow silica fine particle dispersion IC) 12.85 parts by weight Pentaerythritol triacrylate (PETA) 1.43 parts by weight Irgacure 907 (trade name, manufactured by Chivas Specialty Chemicals) 0.1 parts by weight F3035 (trade name, manufactured by NOF CORPORATION) 0.4 parts by weight Methyl Isobutyl Ketone 85.22 parts by weight Comparative example 3 The composition for forming a low refractive index layer in Example 1 was formed in the same manner as in Example 1 except that the composition for forming a low refractive index layer was changed as follows, and a hard coat layer and a low refractive index layer were formed to form a laminate of Comparative Example 3. Got

Surface-treated hollow silica sol (hollow silica fine particle dispersion IB) 12.85 parts by weight Polyethylene Glycol Diacrylate (PEGDA) 1.43 parts by weight Irgacure 907 (trade name, manufactured by Chivas Specialty Chemicals) 0.1 parts by weight F3035 (trade name, manufactured by NOF CORPORATION) 0.4 parts by weight Methyl Isobutyl Ketone 85.22 parts by weight Comparative example 4 The composition for forming a low refractive index layer in Example 1 was formed in the same manner as in Example 1 except that the composition for forming a low refractive index layer was changed as follows, and a hard coat layer and a low refractive index layer were formed to form a laminate of Comparative Example 4. Got

Surface-treated hollow silica sol (hollow silica fine particle dispersion IB) 12.85 parts by weight Pentaerythritol triacrylate (PETA) 1.43 parts by weight Irgacure 907 (trade name, manufactured by Chivas Specialty Chemicals) 0.1 parts by weight Methyl Isobutyl Ketone 85.62 parts by weight Comparative example 5 The composition for forming a low refractive index layer in Example 1 was formed in the same manner as in Example 1 except that the composition for forming a low refractive index layer was changed as follows, and a hard coat layer and a low refractive index layer were formed to form a laminate of Comparative Example 5. Got

Surface untreated hollow silica sol (dispersion of silica-based fine particles I) 7.5 parts by weight Pentaerythritol triacrylate (PETA) 2.5 parts by weight Irgacure 907 (trade name, manufactured by Chivas Specialty Chemicals) 0.15 parts by weight F3035 (trade name, manufactured by NOF CORPORATION) 0.4 parts by weight Methyl Isobutyl Ketone 88.45 parts by weight Each of the laminates thus obtained was subjected to a test evaluation of reflectance, scratch resistance, and antifouling property.

(1) Reflectance measurement Absolute reflectance was measured using a spectrophotometer (UV-3100PC) manufactured by Shimadzu Corporation. The film thickness of the low refractive index layer was set so that the minimum value of the reflectance was around 550 nm in wavelength. From the obtained reflectance curve, the refractive index of the low refractive index layer was obtained by using a simulation.

(2) Abrasion evaluation test Using # 0000 steel wool, it was visually confirmed whether or not there were any scratches when 20 round trips were made under a load of 200 g. The evaluation criteria are as follows.

: No scratches are found : Those with small scratches (5 or less) Δ: Scratches are noticeable, but peeling is not observed. ×: What is peeled off (3) Antifouling property evaluation test The surface of the sample was drawn with the magic of oil-based ink, and the state when it was wiped off with Bencotton was observed. The evaluation criteria are as follows.

: Ink is repellent and the ink can be easily wiped off. : Ink is repellent, and if you rub it firmly, the ink can be wiped off. Δ: Part of the ink was not wiped off and remained ×: Ink could not be wiped off The evaluation results are shown below.<tables num="2"><img file="JP2011237802A_D0003.tif" /></tables>

<figref num="1">The cross section of an example of the antireflection film made of the antireflection laminate according to the present invention is schematically shown.</figref>