JP2019101294A - Optical laminate and picture display unit - Google Patents

Abstract

To provide an optical laminate capable of suppressing an occurrence of a glare while having excellent luminance and capable of preventing a contrast from deteriorating.SOLUTION: An optical laminate includes an optical control layer 10 and an optical layer having a rugged shape on a surface thereof. The optical control layer 10 includes a low refractive index region 11 and a high refractive index region 12 having a larger refractive index than a refractive index of the low refractive index region 11. The low refractive index region 11 and the high refractive index region 12 are each formed in a columnar shape continuously from one face to the other face of the optical control layer.SELECTED DRAWING: Figure 1

Description

The present invention relates to an optical laminate and an image display apparatus.

An image display surface in an image display apparatus such as a liquid crystal display (LCD), a cathode ray tube display (CRT), a plasma display (PDP), an electroluminescence display (ELD), a field emission display (FED), In order to suppress reflection of the background or the like of the observer, an antiglare film having irregularities on the surface and an antireflective film having an antireflective layer on the outermost surface are provided.

The antiglare film scatters external light on the uneven surface of the antiglare layer to suppress reflection of the viewer and the background of the viewer, and the like, mainly the light transmitting substrate and the light transmitting substrate. And an antiglare layer having an uneven surface provided on the material.
The antiglare layer in such an antiglare film usually contains a binder resin and fine particles which are present in the binder resin and which form an uneven surface.
However, when such a conventional antiglare film is disposed on the surface of the image display device, image light may be scattered by the uneven surface of the antiglare layer to cause so-called glare.

To solve such problems, it has been proposed to increase the internal haze of the antiglare film to suppress glare. For example, Patent Document 1 and the like disclose the internal haze by providing a light diffusion layer containing fine particles. An antiglare film is described which is enhanced to suppress glare. For example, Patent Document 2 and the like disclose an antiglare film in which glare is suppressed by enhancing internal haze with fine particles contained in the antiglare layer. Is described.

However, in the antiglare film in which the conventional internal haze is increased, although it is possible to suppress glare, there is a problem in that the contrast and the luminance of the display image of the image display device are reduced. That is, in the conventional antiglare film, if the internal haze is increased to suppress the occurrence of glare, the contrast and the luminance decrease, and if it is attempted to suppress the contrast and the luminance decrease, the glare can not be sufficiently prevented. There was a problem.

JP 2014-126598 A JP, 2016-035575, A

An object of the present invention is to provide an optical laminate and an image display device which can suppress the occurrence of glare and can prevent the decrease in contrast while having the excellent luminance, in view of the above-mentioned current situation.

The present invention is an optical laminate having an optical control layer and an optical layer having a concavo-convex shape on the surface, wherein the optical control layer has a refractive index greater than the refractive index of the low refractive index region and the low refractive index region. And the low refractive index area and the high refractive index area are provided in a columnar shape continuously from one surface of the optical control layer to the other surface. Optical laminate.

In the optical laminate of the present invention, the low refractive index region preferably has a refractive index of 1.40 to 1.50, and the high refractive index region preferably has a refractive index of 1.50 to 1.65.
The shortest distance between adjacent low refractive index regions and / or the shortest distance between adjacent high refractive index regions is 0.1 at the interface on the optical layer side of the optical control layer or the interface opposite to the optical layer side of the optical control layer. It is preferable that it is -15 micrometers.
Further, in the optical laminate of the present invention, when light is made incident from the normal direction of one surface of the optical control layer and the transmitted light intensity is measured, the transmitted light intensity at a diffusion angle of 5 ° is T5 and a diffusion angle of 10 °. The following Formula (1) and Formula (2) may be satisfied, where T10 is the transmitted light intensity at °°, T20 is the transmitted light intensity at the diffusion angle of 20 °, and T40 is the transmitted light intensity at the diffusion angle of 40 °. preferable.
T5 / T10 ≦ 5 (1)
T20 / T40 ≧ 50 (2)
In the optical layered body of the present invention, the optical layer having the concavo-convex shape on the surface has an average spacing of concavities and convexities on the surface as Sm, an average inclination angle of concavities and convexities as θa, and an arithmetic mean roughness of concavities and convexities as Ra. When the ten-point average roughness of the unevenness is Rz, it is preferable to satisfy the following equation.
50 μm <Sm <600 μm
0.1 ° <θa <1.5 °
0.02 μm <Ra <0.25 μm
0.30 μm <Rz <2.00 μm
Preferably, the optical layer having an uneven shape on the surface contains silica fine particles, organic fine particles, and a binder resin, and the uneven shape on the surface is formed of the silica fine particles and the organic fine particles.

The present invention is also an image display device comprising the optical laminate of the present invention.
Hereinafter, the present invention will be described in detail.

As a result of intensive investigations, the present inventors added the fine particles to the light diffusion layer or the like for the purpose of suppressing glare, and in the conventional antiglare film provided with high internal haze, the light incident on the light diffusion layer Is intended to suppress glare by striking and refracting the fine particles and exiting from the light diffusion layer, but when the incident light hits the fine particles and is reflected backward, or light refracted by the fine particles exits the light diffusion layer It has been found that the fact that the light is totally reflected at the interface (surface) with the outside or that the refraction angle of the light emitted from the light diffusion layer is too large is the cause of the decrease in the contrast and the brightness of the display screen.
As a result of further investigation based on such findings, in an optical laminate having a configuration in which an optical control layer and an optical layer having a concavo-convex shape on the surface are laminated, the above optical control layer is continuously divided into regions having different refractive indices. By forming in the thickness direction, it is found that excellent glare prevention performance can be exhibited while suppressing a decrease in contrast and brightness when applied to an image display device, and the present invention is completed. The

The optical laminate of the present invention has an optical control layer and an optical layer having an uneven shape on the surface.
In the optical layered body of the present invention, it is preferable that the optical control layer and the optical layer having a concavo-convex shape on the surface are directly laminated, but within the range which does not impair the effect of the present invention Between the control layer and the optical layer, a gap (air layer), or any layer such as a known transparent base layer or a clear hard coat layer may be provided.
The optical laminate of the present invention may be in the form of a film in which the optical control layer and the optical layer stand on each other, but the optical control layer may be laminated on a light transmitting substrate.

The light transmitting substrate is not particularly limited as long as it has light transmitting properties, and, for example, a cellulose acylate substrate, a cycloolefin polymer substrate, a polycarbonate substrate, an acrylate polymer substrate, a polyester substrate, or And glass substrates.

As said cellulose acylate base material, a cellulose triacetate base material, a cellulose diacetate base material etc. are mentioned, for example.
Moreover, as said cycloolefin polymer base material, the base material etc. which consist of polymers, such as a norbornene-type monomer and a single ring cycloolefin monomer, are mentioned, for example.

Moreover, as said polycarbonate base material, the aromatic polycarbonate base material based on bisphenol (bisphenol A etc.), aliphatic polycarbonate base materials, such as diethylene glycol bis allyl carbonate, etc. are mentioned, for example.

Moreover, as said acrylate type polymer base material, the poly (meth) acrylic-acid base material, the poly (meth) acrylic-acid base material, a methyl (meth) acrylate-butyl (meth) acrylate copolymer group is mentioned, for example Materials etc. In the present specification, (meth) acrylic acid means acrylic acid or methacrylic acid.

As said polyester base material, the base material etc. which have at least 1 sort (s) of a polyethylene terephthalate, a polypropylene terephthalate, a polybutylene terephthalate, and a polyethylene naphthalate as a component are mentioned, for example.

Examples of the glass substrate include glass substrates such as soda lime silica glass, borosilicate glass, alkali-free glass and the like.

Among these, cellulose acylate substrates are preferable because they are excellent in retardation and easy to adhere to a polarizer, and among cellulose acylate substrates, triacetyl cellulose substrates (TAC substrates) are more preferable. The triacetyl cellulose base is a light transmitting base that can have an average light transmittance of 50% or more in the visible light range of 380 to 780 nm. The average light transmittance of the triacetyl cellulose base is preferably 70% or more, more preferably 85% or more.
In addition to pure triacetyl cellulose, the above triacetyl cellulose base material is a combination of cellulose acetate propionate, cellulose acetate butyrate and other components other than acetic acid as fatty acids forming an ester with cellulose, It is also good. In addition, other additives such as cellulose lower fatty acid ester such as diacetyl cellulose, or plasticizers, ultraviolet absorbers, and lubricants may be added to these triacetyl celluloses, as necessary.

From the viewpoint of excellent retardation and heat resistance, cycloolefin polymer substrates are preferable, and from the viewpoint of mechanical properties and heat resistance, polyester substrates are preferable.

The thickness of the light transmitting substrate is not particularly limited, but can be 5 μm or more and 1000 μm or less, and the lower limit of the thickness of the light transmitting substrate is preferably 15 μm or more from the viewpoint of handling and the like, 25 micrometers or more are more preferable. It is preferable that the upper limit of the thickness of the said transparent substrate is 80 micrometers or less from a viewpoint of thin film formation.

The optical control layer is preferably a layer laminated on the light transmitting substrate, and has a low refractive index area and a high refractive index area having a refractive index larger than the refractive index of the low refractive index area. The low refractive index region and the high refractive index region are respectively provided in a columnar shape continuously from one surface to the other surface of the optical control layer. The optical control layer having such a structure exhibits an effect of suppressing glare generated by an optical layer to be described later by, for example, emitting light in a state where light incident from the interface on the light transmitting substrate side is diffused appropriately. .
FIG. 1 is a cross-sectional view schematically showing a part of the optical control layer in the optical laminate of the present invention, but as shown in FIG. 1, in the optical laminate of the present invention, in the optical control layer 10 The low refractive index area 11 and the high refractive index area 12 are continuously provided in a columnar shape in the thickness direction. For this reason, the incident light from the side of the light transmitting substrate (not shown) repeats total reflection when the incident angle at the interface between the low refractive index area 11 and the high refractive index area 12 is equal to or less than the critical angle. Then, the incident light is emitted from the side opposite to the light transmitting substrate side of the optical control layer 10. When the incident angle of the incident light at the interface between the low refractive index area 11 and the high refractive index area 12 exceeds the critical angle, it is transmitted without being totally reflected and emitted from the optical control layer 10. Thus, since incident light is transmitted through the optical control layer 10, the light strikes on the fine particles like the light diffusion layer containing the conventional fine particles described above, and the light reflected back or refracted by the fine particles exits the light diffusion layer It is possible to suppress total reflection at the interface (surface) with the outside or excessive increase of the refraction angle of the light emitted from the light diffusion layer, and as a result, the optical laminate of the present invention is used in the image display device. When the body is used, it is possible to suppress the decrease in the contrast and the luminance of the display screen.

In the optical laminate of the present invention, the shape of the low refractive index region and the high refractive index region in the optical control layer is particularly limited as long as the low refractive index region and the high refractive index region are continuously provided in the thickness direction of the optical control layer. For example, like the optical control layer 20 shown in FIG. 2, a structure in which a plate-like low refractive index region 21 and a plate-like high refractive index region 22 are alternately provided continuously (a louver structure The optical control layer 30 shown in FIG. 3 may have a structure (sea-island structure) in which a plurality of cylindrical low refractive index areas 31 are provided in the high refractive index area 32. .
With a louver structure such as the optical control layer 20 shown in FIG. 2, light transmitted through the optical control layer 20 is emitted in one direction, that is, in a diffused state in the left and right direction of FIG. In the sea-island structure such as the optical control layer 30, light transmitted through the optical control layer 30 is emitted in all directions, that is, in a state of being isotropically diffused.
In addition, the optical laminated body of this invention may be provided so that the low refractive index area | region and high refractive index area | region which were shown in FIG.2 and FIG.3 may become reverse, for example. The low refractive index region 21 and the high refractive index region 22 in FIG. 2 may be in the form of a plate having an uneven thickness, and the low refractive index region 31 shown in FIG. 3 may be one of the optical control layers or In both planes, any shape such as a circle, an ellipse, or a polygon may be used.
FIG. 2 is a perspective view schematically showing an example of the optical laminate of the present invention, and FIG. 3 is a perspective view schematically showing another example of the optical laminate of the present invention.

An optical control layer having such a low refractive index region and a high refractive index region is, for example, stirring two polymerizable compounds having different refractive indexes under high temperature conditions of 40 to 80 ° C. to form a uniform liquid mixture. After adding an additive such as a photopolymerization initiator, if necessary, to the liquid mixture, while stirring until uniform, it is prepared by further adding a dilution solvent as needed to achieve a desired viscosity. It can form using the composition for optical control layers.

Among the two polymerizable compounds having different refractive indices, the type of the polymerizable compound having a higher refractive index (hereinafter, also referred to as component (A)) is not particularly limited, but the main component thereof contains a plurality of aromatic rings It is preferable to use (meth) acrylic acid ester.
By including a specific (meth) acrylic acid ester as the component (A), sufficient compatibility with the polymerizable compound having a lower refractive index (hereinafter, also referred to as component (B)) in the monomer stage It is presumed that the compatibility with the component (B) can be lowered to a predetermined range at a stage where a plurality of chains are connected in the process of polymerization, and that a predetermined internal structure can be formed more efficiently. Be done.
Furthermore, by including a specific (meth) acrylic acid ester as the component (A), the refractive index of the high refractive index region derived from the component (A) in the optical control layer can be increased, The difference with the refractive index of the low refractive index region derived from the component) can be adjusted to a predetermined value or more. Therefore, by including a specific (meth) acrylic acid ester as the component (A), it is possible to efficiently obtain a predetermined optical control layer composed of regions having different refractive indices, in combination with the characteristics of the component (B) described later. be able to.
In the present specification, “(meth) acrylic acid ester containing plural aromatic rings” means a compound having plural aromatic rings in the ester residue part of (meth) acrylic acid ester, “( "Meth) acrylic acid" means acrylic acid and methacrylic acid.

Examples of the (meth) acrylic acid ester containing a plurality of aromatic rings as the component (A) include biphenyl (meth) acrylate, naphthyl (meth) acrylate, anthracyl (meth) acrylate, and (meth) acrylic acid. Examples thereof include benzylphenyl acid, fluorene (meth) acrylate and the like, or those in which a part of them is substituted by halogen, alkyl, alkoxy, halogenated alkyl and the like, and the like.

It is preferable that the weight molecular weight of the said (A) component exists in the range of 200-2500.
Therefore, it is more preferable to make the molecular weight of the said (A) component into the value within the range of 240-1500, and it is further more preferable to set it as the value within the range of 260-1000.
In addition, the weight average molecular weight of the said (A) component can be calculated | required from the composition of a molecule, and the calculated value obtained from the atomic weight of a constituent atom, and it measures as a weight average molecular weight using gel permeation chromatography (GPC). It can also be done.

It is preferable to make the refractive index of the said (A) component into the value within the range of 1.50-1.65.
By setting the refractive index of the component (A) to a value within this range, the refractive index of the high refractive index region derived from the component (A) and the refractive index of the low refractive index region derived from the component (B) Can be more easily adjusted to obtain an optical control layer with a predetermined internal structure more efficiently.
If the refractive index of the component (A) is less than 1.50, the difference from the refractive index of the component (B) may be too small, which may make it difficult to obtain an effective light diffusion angle region. On the other hand, when the refractive index of the component (A) exceeds 1.65, the difference with the refractive index of the component (B) increases, but even the apparent compatibility state with the component (B) It may be difficult to form.
The refractive index of the component (A) is more preferably in the range of 1.55 to 1.60, and still more preferably in the range of 1.56 to 1.59.
In addition, the refractive index of (A) component mentioned above means the refractive index of (A) component before hardening by light irradiation.
Moreover, the said refractive index can be measured according to JIS K 0062, for example.

It is preferable to make content of the said (A) component in the said composition for optical control layers into the value within the range of 25-400 mass parts with respect to 100 mass parts of (B) components mentioned later. If the amount is less than 25 parts by mass, the proportion of the component (A) to the component (B) decreases, and the width of the high refractive index region derived from the component (A) is low refractive index derived from the component (B) It may be too small compared to the width of the region, and it may be difficult to obtain an optical control layer having a predetermined internal structure. In addition, the length of the predetermined internal structure in the thickness direction of the optical control layer may be insufficient, and the light diffusibility may not be exhibited. On the other hand, when the content of the component (A) exceeds 400 parts by mass, the proportion of the component (A) to the component (B) increases, and the width of the high refractive index region derived from the component (A) The width of the low refractive index region derived from the component (B) is excessively large, and it may be difficult to obtain an optical control layer having a predetermined structure. In addition, the length of the predetermined internal structure in the thickness direction of the optical control layer may be insufficient, and the light diffusibility may not be exhibited. Therefore, the content of the component (A) is more preferably 40 to 300 parts by mass with respect to 100 parts by mass of the component (B), and 50 to 200 parts by mass It is further preferred that

The type of the polymerizable compound having a lower refractive index (component (B)) among the two polymerizable compounds having different refractive indexes is not particularly limited. For example, a compound having a functional group such as acrylate, etc. And compounds having one or more unsaturated bonds.
As a compound which has said 1 unsaturated bond, an ethyl (meth) acrylate, an ethylhexyl (meth) acrylate etc. can be mentioned, for example.
Examples of the compound having two or more unsaturated bonds include diethylene glycol di (meth) acrylate, dipropylene glycol di (meth) acrylate, neopentyl glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate, and polypropylene di. (Meth) acrylate, dioxane glycol di (meth) acrylate, methoxypolyethylene glycol di (meth) acrylate, methoxypolypropylene glycol di (meth) acrylate, dicyclopentadi (meth) acrylate, tricyclodecane di (meth) acrylate, tri Methylolpropane tri (meth) (meth) acrylate, ditrimethylolpropane tetra (meth) acrylate, pentaerythritol tetra (meth) acrylate, di Pentaerythritol penta (meth) acrylate, tripentaerythritol octa (meth) acrylate, tetrapentaerythritol deca (meth) acrylate, isocyanuric acid tri (meth) acrylate, isocyanuric acid di (meth) acrylate, epoxy (meth) acrylate, urethane ( Examples include meta) acrylates, polyester (meth) acrylates, polyether (meth) acrylates, silicone (meth) acrylates and the like.

It is preferable to make the refractive index of the said (B) component into the value within the range of 1.40-1.50. By setting the refractive index of the component (B) within such a range, the difference between the high refractive index region derived from the component (A) and the refractive index of the low refractive index region derived from the component (B) By adjusting more easily, an optical control layer with a predetermined polygon area can be obtained more efficiently.
That is, when the refractive index of the component (B) becomes a value of less than 1.40, the difference with the refractive index of the component (A) increases, but the compatibility with the component (A) extremely deteriorates. It may not be possible to form the internal structure of the On the other hand, when the refractive index of the component (B) exceeds 1.50, the difference from the refractive index of the component (A) becomes too small, making it difficult to obtain the desired incident angle dependency. There is a case.
Accordingly, the refractive index of the component (B) is more preferably in the range of 1.45 to 1.49, and still more preferably in the range of 1.46 to 1.48.
In addition, the refractive index of (B) component mentioned above means the refractive index of (B) component before hardening by light irradiation.

Moreover, it is preferable to make the difference of the refractive index of (A) component mentioned above, and the refractive index of (B) component into the value of 0.01 or more.
By setting the difference in refractive index to a value within a predetermined range, it is possible to obtain an optical control layer having better incident angle dependency in transmission and diffusion of light and a wider light diffusion incident angle region. .
That is, when the difference in the refractive index is less than 0.01, the angle range in which the incident light is totally reflected in the predetermined optical control layer becomes narrow, so the opening angle in light diffusion may become excessively narrow. is there. On the other hand, if the difference between the refractive indices is an excessively large value, the compatibility between the components (A) and (B) may be too poor to form a predetermined internal structure.
Therefore, it is more preferable to set the difference between the refractive index of the component (A) and the refractive index of the component (B) to a value within the range of 0.05 to 0.5, preferably 0.1 to 0.2. It is further preferable to set the value within the range of

It is preferable to make content of (B) component in the said composition for optical control into the value within the range of 10-80 mass% with respect to 100 mass% of total amounts of the composition for optical control layers. When the content of the component (B) is less than 10% by mass, the proportion of the component (B) to the component (A) decreases, and the width of the low refractive index region derived from the component (B) is This is because it may become excessively small compared to the width of the high refractive index region derived from the component (A), and it may be difficult to obtain a predetermined internal structure having good incident angle dependency. In addition, the length of the predetermined internal structure in the thickness direction of the optical control layer may be insufficient. On the other hand, when the content of the component (B) exceeds 80% by mass, the proportion of the component (B) to the component (A) increases, and the low refractive index region derived from the component (B) The width may be too large compared to the width of the high refractive index region derived from the component (A), and it may be difficult to obtain a predetermined internal structure having good incident angle dependency. It is for. Moreover, it is because the length of the predetermined internal structure in the thickness direction of an optical control layer may become inadequate.
Therefore, it is more preferable to make content of (B) component into the value within the range of 20-70 mass% with respect to 100 mass% of total amounts of the composition for optical control layers, and 30-60 mass% It is further preferable to set the value within the range.

In the composition for an optical control layer, it is preferable to contain a photopolymerization initiator as the component (C), if desired.
By containing the said photoinitiator, when an active energy ray is irradiated with respect to the composition for optical control layers, a predetermined | prescribed internal structure can be formed efficiently.
Here, the photopolymerization initiator refers to a compound that generates radical species by irradiation of active energy rays such as ultraviolet rays.

As such a photopolymerization initiator, for example, benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin n-butyl ether, benzoin isobutyl ether, acetophenone, dimethylaminoacetophenone, 2,2-dimethoxy-2-phenylacetophenone , 2,2-diethoxy-2-phenylacetophenone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 1-hydroxycyclohexyl phenyl ketone, 2-methyl-1- [4- (methylthio) phenyl] -2-morpholino-propan-1-one, 4- (2-hydroxyethoxy) phenyl-2- (hydroxy-2-propyl) ketone, benzophenone, p-phenylbenzophenone, 4,4-diethyl Minobenzophenone, dichlorobenzophenone, 2-methylanthraquinone, 2-ethylanthraquinone, 2-tertiarybutylanthraquinone, 2-aminoanthraquinone, 2-methylthioxanthone, 2-ethylthioxanthone, 2-chlorothioxanthone, 2,4-dimethylthioxanthone, 2,4-Diethylthioxanthone, benzyl dimethyl ketal, acetophenone dimethyl ketal, p-dimethylamine benzoate, oligo [2-hydroxy-2-methyl-1- [4- (1-methylvinyl) phenyl] propane, etc. And one of these may be used alone, or two or more may be used in combination.
In addition, as content in the case of containing a photoinitiator, it shall be a value within the range of 0.2-20 weight part with respect to 100 weight part of total amounts of (A) component and (B) component. The value is preferably in the range of 0.5 to 15 parts by weight, and more preferably in the range of 1 to 10 parts by weight.

In addition, other additives can be added as appropriate as long as the effects of the present invention are not impaired.
Examples of other additives include antioxidants, ultraviolet absorbers, antistatic agents, polymerization accelerators, polymerization inhibitors, infrared absorbers, plasticizers, diluents, and leveling agents.
In addition, it is preferable to generally set content of other additives to the value within the range of 0.01-5 mass parts with respect to 100 mass parts of total amounts of (A) component and (B) component, It is more preferable to set it as the value within the range of 0.02 to 3 parts by mass, and it is further preferable to set it to the value within the range of 0.05 to 2 parts by mass.

In order to form an optical control layer using the composition for optical control layers, first, the composition for optical control layers is coated on the light transmitting substrate described above to form a coating layer.
Examples of a method of applying the composition for an optical control layer on the light transmitting substrate include a knife coating method, roll coating method, bar coating method, blade coating method, die coating method, comma coating method, and gravure coating. The reaction can be carried out by a conventionally known method such as a method.
At this time, it is preferable to set the thickness of the coating layer to a value within the range of 100 to 700 μm.

Next, the coating layer is irradiated with active energy rays to make the coating layer an optical control layer composed of a plurality of regions having different refractive indexes.
Specifically, parallel rays with high parallelism of light rays are irradiated to the coating layer.
Here, the parallel light means substantially parallel light which does not have a spread even when viewed from any direction.
More specifically, for example, as shown in FIG. 6A, after the irradiation light 50 from the point light source 202 is collimated by the lens 204, the application layer 101 provided on the process sheet 102 is irradiated. After the irradiation light 50 from the linear light source 125 is collimated by the irradiation light collimating member 200 (200a, 200b) as shown in FIGS. 6 (b) to 6 (c), the coating layer 101 is formed. It is preferable to

As shown in FIG. 6D, the irradiation light collimating member 200 is a direction parallel to the axial direction of the linear light source 125 in which the direction of the light is random among the direct light from the linear light source 125, For example, direct light from the linear light source 125 can be converted into parallel light by unifying the direction of light using the light shielding member 210 such as the plate-like member 210a or the cylindrical member 210b.
More specifically, of the direct light from the linear light source 125, light with low parallelism to the light shielding member 210 such as the plate-like member 210a or the cylindrical member 210b contacts these and is absorbed.
Therefore, only light having high parallelism to the light shielding member 210 such as the plate-like member 210a and the cylindrical member 210b, that is, only parallel light passes through the irradiation light collimating member 200, and as a result, the linear light source 125 The direct light from the light source is converted into parallel light by the irradiation light collimating member 200.
The material of the light shielding member 210 such as the plate-like member 210a and the cylindrical member 210b is not particularly limited as long as it can absorb light having low parallelism to the light shielding member 210, for example, heat resistant black A painted Alster steel plate or the like can be used.

Moreover, it is preferable to set the parallelism of the irradiation light to a value of 10 ° or less.
The reason for this is that the optical control layer having the above-described predetermined internal structure can be efficiently and stably formed by setting the parallelism of the irradiation light to a value within such a range.
Therefore, it is more preferable to set the parallelism of the irradiation light to a value of 5 ° or less, and more preferably to a value of 2 ° or less.

Further, as the irradiation angle of the irradiation light, as shown in FIG. 7, the irradiation angle θ3 when the angle of the normal to the surface of the coating layer 101 is 0 ° is usually in the range of -80 to 80 °. It is preferable to use a value.
The reason for this is that when the irradiation angle has a value outside the range of -80 to 80 °, the influence of reflection or the like on the surface of the coating layer 101 becomes large, and an optical function layer having the above-mentioned predetermined internal structure is formed. Because it may be difficult.
In addition, FIG. 7 is explanatory drawing of an active energy irradiation process.

Moreover, although an ultraviolet-ray, an electron beam, etc. are mentioned as irradiation light, It is preferable to use an ultraviolet-ray.
The reason is that, in the case of electron beam, the polymerization rate is very fast, so that the components (A) and (B) can not be sufficiently phase separated in the polymerization process, and the optical control layer having the above-mentioned predetermined internal structure It is because it may be difficult to form. On the other hand, when compared with visible light etc., the ultraviolet rays are more abundant in the variation of the UV curable resin which can be cured by the irradiation and the photopolymerization initiator which can be used, so that the components (A) and (B) This is because the range of choices of can be expanded.

Moreover, as conditions of irradiation of an ultraviolet-ray, it is preferable to make peak illumination intensity on the surface of a coating layer into the value within the range of 0.1-10 mW / cm < ² >.
The reason for this is that when the peak illuminance becomes a value less than 0.1 mW / cm ² , it may be difficult to clearly form the optical control layer having the above-described predetermined internal structure. On the other hand, when the peak illuminance exceeds 10 mW / cm ² , it hardens before the phase separation of the (A) component and the (B) component proceeds, and conversely, an optical control layer of a specific structure is clarified. It may be difficult to form it.
Therefore, it is more preferably set to a value within the range of the peak irradiance 0.3~8mW / cm ² of the coating layer surface in the ultraviolet irradiation, further to a value within the range of 0.5~6mW / cm ² preferable.

Moreover, it is more preferable to make the integral light quantity in the coating layer surface in ultraviolet irradiation into the value within the range of 5-200 mJ / cm < ² >.
The reason for this is that when the integrated light amount is less than 5 mJ / cm ^2, it may be difficult to sufficiently extend the high refractive index area and the low refractive index area from the upper side to the lower side. is there. On the other hand, when the integrated light amount exceeds 200 mJ / cm ² , coloring may occur in the obtained optical control layer.
Therefore, it is more preferably set to a value within the range of accumulated light amount of 7~150mJ / cm ² in the coating layer surface of the ultraviolet radiation, more preferably to a value within the range of 10 to 100 mJ / cm ^2.
In addition, it is preferable to optimize peak illumination intensity and integrated light quantity by the internal structure formed in a film.

Moreover, it is preferable to perform irradiation of the active energy ray with respect to the said application layer in non-oxygen atmosphere. By performing active energy ray irradiation in a non-oxygen atmosphere, the influence of oxygen inhibition can be suppressed, and an optical control layer having a predetermined internal structure can be efficiently formed.
If the active energy ray irradiation is performed under an oxygen atmosphere instead of a non-oxygen atmosphere, the predetermined internal structure can be formed at a very shallow position near the surface of the coating layer if the irradiation is performed with high illuminance. Although it is possible, it may be difficult to obtain the refractive index difference necessary for light diffusion. On the other hand, when irradiated with low illuminance, it may be difficult to form a predetermined internal structure under the influence of oxygen inhibition.
The “non-oxygen atmosphere” means a condition in which the upper surface of the coating layer is not in direct contact with the oxygen atmosphere or the atmosphere containing oxygen.
Therefore, for example, laminating the film on the upper surface of the coating layer, or replacing the air with nitrogen gas, and performing the active energy ray irradiation in a state where nitrogen purge is performed, in a "non-oxygen atmosphere" It corresponds to the active energy ray irradiation of

Moreover, it is especially preferable to perform active energy ray irradiation in the state which laminated the active energy ray permeable sheet with respect to the upper surface of a coating layer as active energy ray irradiation in "non-oxygen atmosphere" mentioned above.
By performing active energy ray irradiation in this way, the influence of oxygen inhibition can be effectively suppressed, and an optical control layer having a predetermined internal structure can be formed more efficiently.
For example, by laminating an active energy ray transmitting sheet on the upper surface of the coating layer, the sheet can be transmitted while being stably prevented from contacting the upper surface of the coating layer with oxygen, and coating is efficiently performed. The layer can be irradiated with active energy rays.
In addition, as said active energy ray permeable sheet, if an active energy ray can be permeate | transmitted, it can be used without a restriction | limiting especially.

In the active energy ray transmitting sheet, the arithmetic average roughness of the surface not in contact with the coating layer is preferably 2 μm or less, more preferably less than 1 μm. With such an arithmetic average roughness, it is possible to effectively prevent the active energy ray from being diffused by the active energy ray transmitting sheet, and to form a predetermined internal structure efficiently.
The arithmetic mean roughness can be determined according to JIS B 0601.
From the same viewpoint, the haze value of the active energy ray transmitting sheet is preferably a value within the range of 0 to 8%, and particularly preferably a value within the range of 0.1 to 5%.
In addition, the said haze value can be calculated | required by JISK7136.

Moreover, it is preferable that the image definition (slit width: 0.125 mm, 0.25 mm, 0.5 mm, 1 mm and 2 mm total value) of the said active energy ray permeation sheet is a value within the range of 200-500. It is particularly preferable that the value is in the range of 300 to 490. If the image definition is a value within such a range, the active energy ray can be transmitted through the coating layer without loss in the sheet, and a predetermined internal structure can be efficiently formed.
In addition, the said image definition can be calculated | required by JISK7374.
From the same point of view, the transmittance of the active energy ray transmitting sheet to light of wavelength 360 nm is preferably in the range of 30 to 100%, and in the range of 45 to 95%. Particularly preferred.

It is also preferable to irradiate an active energy ray separately from the above-mentioned process so that it may become the light quantity which the said coating layer hardens | cures fully.
Since the active energy ray at this time is intended to sufficiently cure the coating layer, it is preferable to use irradiation light whose traveling direction is random.

In the predetermined internal structure of the optical control layer, the difference in refractive index between the regions having different refractive indices, ie, the difference between the refractive index in the high refractive index region and the refractive index in the low refractive index region is 0.01 or more It is preferable to use a value. By setting the difference in refractive index to a value of 0.01 or more, incident light can be stably reflected in a predetermined internal structure.
The refractive index difference is preferably 0.05 or more, more preferably 0.1 or more. In addition, although the difference of the refractive index mentioned above is so preferable that it is large, it is thought that about 0.3 is an upper limit from a viewpoint of selecting the material which can form a predetermined | prescribed internal structure.

Further, in a predetermined internal structure, it is preferable to set the refractive index of the high refractive index region to a value within the range of 1.50 to 1.65. When the refractive index of the high refractive index area is less than 1.50, the difference from the low refractive index area may be too small, and it may be difficult to obtain a predetermined internal structure. When the refractive index of the above becomes a value exceeding 1.65, the compatibility between the materials in the composition for an optical functional layer may become excessively low.
It is more preferable to set the refractive index of the high refractive index area in the above-mentioned predetermined internal structure to a value within the range of 1.55 to 1.60, and it is further preferable to set the value within the range of 1.56 to 1.59. preferable.
The refractive index of the high refractive index region can be measured, for example, according to JIS K 0062.

In a predetermined internal structure, it is preferable to set the refractive index of the low refractive index region to a value within the range of 1.40 to 1.50. When the refractive index of the low refractive index region is a value less than 1.40, the rigidity of the obtained optical control layer may be lowered, and when it is a value exceeding 1.50, the refractive index of the high refractive index region is May be too small and it may be difficult to obtain a given internal structure.
The refractive index of the low refractive index region in the predetermined internal structure is more preferably in the range of 1.45 to 1.49, and further preferably in the range of 1.46 to 1.48. preferable.
The refractive index of the low refractive index region can be measured, for example, according to JIS K 0062.

In the optical laminate of the present invention, the shortest distance between adjacent low refractive index regions and / or between adjacent high refractive index regions at the optical layer side interface of the optical control layer or the interface opposite to the optical layer side. The shortest distance of is preferably 0.1 to 15 .mu.m. By setting the distance between these regions to a value within the range of 0.1 to 15 μm, incident light can be stably reflected within a predetermined internal structure.
When the distance between the adjacent high refractive index area and the adjacent low refractive index area has a value of less than 0.1 μm, it may be difficult to exhibit light diffusion regardless of the incident angle of the incident light. On the other hand, when the distance between the adjacent high refractive index area and the adjacent low refractive index area exceeds 15 μm, the light traveling straight in the predetermined internal structure increases and the uniformity of the diffused light may be deteriorated. is there.
Therefore, the shortest distance between adjacent low refractive index regions and the shortest distance between adjacent high refractive index regions are 0.5 to 10 μm at the optical layer side interface of the optical control layer or the interface opposite to the optical layer side. It is more preferable to set the value in the range of 1 to 5 and it is further preferable to set the value in the range of 1 to 5 .mu.m.
Here, the shortest distance between adjacent low refractive index regions and / or the shortest distance between adjacent high refractive index regions at the interface on the optical layer side of the optical control layer or the interface opposite to the optical layer side is the The optical layered product of the invention can be measured by observing it with an optical digital microscope from the optical layer side or the side opposite to the optical layer side.
Further, the shortest distance between adjacent low refractive index regions and / or the shortest distance between adjacent high refractive index regions at the interface on the optical layer side of the optical control layer or the interface opposite to the optical layer side is two or more It can be regarded as the distance between the adjacent high refractive index area and the adjacent low refractive index area in the cross section in the thickness direction of the optical control layer where the high refractive index area and two or more low refractive index areas appear. The distance between the adjacent high refractive index area and the adjacent low refractive index area in the cross section in the thickness direction of the optical control layer can also be measured by observing with an optical digital microscope.

It is preferable to make the film thickness of the said optical control layer into the value within the range of 30-300 micrometers. When the total film thickness of the optical control layer is less than 30 μm, the incident light traveling straight in the predetermined internal structure may increase, which may make it difficult to exhibit light diffusion, and when the value exceeds 300 μm. When the composition for the optical control layer is irradiated with active energy rays to form a predetermined internal structure, the progressing direction of photopolymerization is diffused by the internal structure formed at the beginning, and the predetermined internal structure is formed. Can be difficult to form. The film thickness of the optical control layer is more preferably in the range of 40 to 250 μm, and still more preferably in the range of 50 to 200 μm.

The above optical control layer measures the transmitted light intensity when light is made incident from the normal direction of one surface of the optical control layer, and the transmitted light intensity at a diffusion angle of 5 ° is T5 at the diffusion angle of 10 °. Assuming that the transmitted light intensity is T10, the transmitted light intensity at a diffusion angle of 20 ° is T20, and the transmitted light intensity at a diffusion angle of 40 ° is T40, it is preferable to satisfy the following formulas (1) and (2).
T5 / T10 ≦ 5 (1)
T20 / T40 ≧ 50 (2)
By satisfying the above equation (1), the change in transmitted light intensity in the vicinity of the normal transmission direction (diffusion angle 0 °) becomes small, so that diffused light for suppressing glare is sufficiently included. The left side of the above formula (1) is more preferably 4 or less, still more preferably 3 or less.
Further, by satisfying the formula (2), the diffused light is rapidly reduced at an angle away from the regular transmission direction, so that the deterioration of the luminance and the contrast can be suppressed. The left side of the above formula (2) is more preferably 100 or more, still more preferably 200 or more.
In the specification of the present invention, the measurement of the transmitted light intensity can be performed by a variable-angle photometer. The variable angle photometer is not particularly limited, but in the present invention, "GC5000L" manufactured by Nippon Denshoku Kogyo Co., Ltd. was used.
The transmitted light intensity is a value at each diffusion angle when the transmitted light intensity in the normal transmission direction (a diffusion angle of 0 °) at that time is 100000 when calibration is performed in a state where no sample is set. Further, in the measurement of the transmitted light intensity, the sample is placed in the apparatus, a light beam is made incident from the normal direction of the sample surface, and the normal transmission direction of the transmitted and diffused light is made a diffusion angle of 0 ° within a predetermined range. Measure the intensity of the transmitted diffused light. Here, the transmitted light intensity takes an average value on the-side and + side. For example, the transmitted light intensity at a diffusion angle of 10 ° is determined as an average value of the transmitted light intensity at a diffusion angle of −10 ° and the transmitted light intensity at + 10 °. When the denominator is 0 in the calculation of the equations (1) and (2), the left side of each equation is regarded as infinite.
The above formulas (1) and (2) can be suitably satisfied, for example, by appropriately controlling parameters of the surface asperity shape of the optical layer to be described later.

In the optical laminate of the present invention, an optical layer having a concavo-convex shape on the surface thereof is laminated on the side opposite to the light transmitting substrate side of the optical control layer.
The said optical layer is a layer which has uneven | corrugated shape on the surface, and ensures the anti-glare performance of the optical laminated body of this invention.
In order to obtain the above-mentioned concavo-convex shape, (1) a composition containing fine particles and a binder resin is applied to a light transmitting substrate to form asperities, (2) two mutually incompatible binder resins are included The composition is applied to a light transmitting substrate to form unevenness by phase separation, (3) a binder resin is applied to a light transmitting substrate to transfer an embossing roll having an uneven shape to form unevenness, etc. And the like. Among these, the method (1) is preferable from the viewpoint of easiness of production, and will be described in detail below.

When the optical layer is obtained by the method (1), the optical layer preferably contains inorganic fine particles and / or organic fine particles as a fine particle and a binder resin, and the uneven shape of the surface of the optical layer is More preferably, they are formed of aggregates of inorganic fine particles and organic fine particles described later.
The uneven shape formed on the surface of such an optical layer is formed on the surface of the optical layer by single particles (for example, organic particles) or aggregates of single particles (for example, aggregates of inorganic particles). It is preferable that the slope of the convex portion be gentler and smoother than the uneven shape.
It is presumed that this is because the inorganic fine particles and the organic fine particles are distributed in a specific state in the optical layer, as described later.

It is preferable that the said inorganic fine particle forms an aggregate, and has what was contained roughly and densely in the said optical layer. The aggregate of the inorganic fine particles is roughly distributed in the optical layer, whereby a smooth uneven shape is formed on the surface of the optical layer.
The above-mentioned "roughly distributed in the optical layer" means a region in which aggregates of the inorganic fine particles are densely distributed in the optical layer (electron microscope (transmission type such as TEM or STEM is preferable)) When an arbitrary cross section in the thickness direction of the optical layer is observed under conditions of a magnification of 10,000 times, an area in which the area ratio of aggregates of inorganic fine particles in an observation area of 2 .mu.m square is 5% or more; When an arbitrary cross section in the thickness direction of the optical layer is observed under the conditions of 10,000 magnifications in a region where aggregates of inorganic fine particles are roughly distributed (electron microscope (transmission type such as TEM, STEM is preferable)) And a plurality of areas where the area ratio of the aggregates of the inorganic fine particles occupying an observation area of 2 μm square is less than 1%). That is, in the optical layer, the aggregates of the inorganic fine particles are dispersed nonuniformly.
In addition, distribution of the aggregate of such an inorganic fine particle can be easily discriminate | determined by cross-sectional electron microscope observation of the thickness direction of the said optical layer. The area ratio of the aggregates of the inorganic fine particles can be calculated, for example, using image analysis software.
Such inorganic fine particles are not particularly limited, but for example, silica fine particles are preferable. Hereinafter, the inorganic fine particles will be described as silica fine particles.

The silica fine particles are preferably surface-treated. The surface treatment of the silica fine particles makes it possible to preferably control the degree of coarse distribution of the aggregates of the silica fine particles in the optical layer, and it is densely distributed around the organic fine particles. The effect can be controlled within a reasonable range. In addition, the chemical resistance and the saponification resistance of the silica fine particle itself can be improved.

As said surface treatment, the method etc. which process the said silica fine particle with the silane compound which has an octyl group are mentioned, for example.
Here, usually, hydroxyl groups (silanol groups) are present on the surface of the silica fine particles, but the hydroxyl groups on the surface of the silica fine particles are reduced by the surface treatment, and the BET method of the silica fine particles is performed. As the specific surface area to be measured is reduced, excessive aggregation of the silica fine particles can be prevented, and the above-described effects are exhibited.

Moreover, it is preferable that the said silica particle consists of amorphous silica. When the above-mentioned silica fine particles are made of crystalline silica, the Lewis acidity of the silica fine particles becomes strong due to lattice defects contained in the crystal structure, and it may be impossible to control the excessive aggregation of the above-mentioned silica fine particles.

As such silica fine particles, for example, fumed silica is preferably used because it is easy to aggregate itself and to easily form aggregates described later. Here, the fumed silica refers to amorphous silica having a particle diameter of 200 nm or less prepared by a dry method, and is obtained by reacting a volatile compound containing silicon in a gas phase. Specifically, for example, silicon compounds such as those produced by hydrolyzing SiCl ₄ in a flame of oxygen and hydrogen can be mentioned. Specifically, AEROSIL R 805 (made by Nippon Aerosil Co., Ltd.) etc. are mentioned, for example.

Although it does not specifically limit as content of the said silica particle, It is preferable that it is 0.1-5.0 mass% in the said optical layer. If it is less than 0.1% by mass, a dense distribution may not be sufficiently formed around the above-mentioned organic fine particles, and if it exceeds 5.0% by mass, aggregates are excessively formed to cause internal diffusion and / or internal diffusion. Due to the large surface irregularities in the optical layer, the problem of white blur may occur. A more preferable lower limit is 0.5% by mass, and a more preferable upper limit is 3.0% by mass.

The fine silica particles preferably have an average primary particle diameter of 1 to 100 nm. If it is less than 1 nm, a dense distribution may not be sufficiently formed around the organic fine particles. If it exceeds 100 nm, a dense distribution may not sufficiently be formed around the organic fine particles, and Light may be diffused and the dark room contrast of an image display using the optical laminate of the present invention may be poor. A more preferable lower limit is 5 nm, and a more preferable upper limit is 50 nm.
The average primary particle diameter of the silica fine particles is a value measured using an image processing software from an image of a cross-sectional electron microscope (TEM, STEM, etc. transmission type and magnification is preferably 50,000 or more) is there.

In the present invention, the aggregate of the silica fine particles preferably has a structure in which the silica fine particles described above in the optical layer are linked in a beaded shape (pearl necklace shape).
By forming an aggregate in which the silica fine particles are linked in a beaded shape in the optical layer, as described later, the surface asperity shape of the optical layer can be suitably made into a smooth shape. The above-mentioned structure in which the silica fine particles are linked in a beaded shape is, for example, a structure (linear structure) in which the silica fine particles are continuously connected in a straight line, a structure in which plural linear structures are intertwined, the above-mentioned straight chain structure There may be any structure such as a branched structure having one or more side chains in which a plurality of silica fine particles are continuously formed.

Moreover, it is preferable that the aggregate of the said silica particle is 100 nm-1 micrometer of average particle diameters. If it is less than 100 nm, a dense distribution may not be sufficiently formed around the organic fine particles, and if it exceeds 1 μm, a dense distribution may not sufficiently be formed around the organic fine particles. Light may be diffused by the aggregates, and the dark room contrast of the image display device using the optical laminate of the present invention may be poor. The more preferable lower limit of the average particle diameter of the above aggregate is 200 nm, and the more preferable upper limit is 800 nm.
In addition, the average particle diameter of the aggregate of the said silica particle selects the area | region of 5 micrometers square containing many aggregates of a silica particle from the observation (about 10,000 to 20,000 times) with a cross-sectional electron microscope, The particle size of the aggregate of the fine particles is measured, and the particle size of the aggregate of the top 10 silica fine particles is averaged. The above “particle diameter of the aggregate of silica fine particles” is such that when the cross section of the aggregate of silica fine particles is sandwiched between any two parallel straight lines, the distance between the two straight lines becomes maximum 2 It is measured as the distance between straight lines in a combination of straight lines in a book. Further, the particle diameter of the aggregate of the silica fine particles may be calculated using image analysis software.

It is preferable that the optical layer contains organic fine particles, and aggregates of the silica fine particles are densely distributed around the organic fine particles.
In addition, as described above, the aggregate of the silica fine particles is roughly contained in the optical layer, and in the optical layer, the aggregate of many silica fine particles is present around the organic fine particles. It is preferable that a region in which there is a region and a region in which only the aggregates of the silica fine particles are densely distributed are formed.
Here, when the cross section of the optical layer is observed with an electron microscope, the aggregate of the silica fine particles closely distributed around the organic fine particles is not only the cross section passing through the center of the organic fine particles but also the offset from the center of the organic fine particles. A densely distributed state is also observed in the cross section.
The phrase "the aggregates of the silica fine particles are densely distributed around the organic fine particles" means an optical layer under conditions of a magnification of 20,000 times with an electron microscope (a transmission type such as TEM or STEM is preferable) When the cross section where the organic fine particles in the thickness direction are observed is observed with a microscope, the area ratio of the aggregates of the silica fine particles in the area outside the organic fine particles and excluding the organic fine particles is 10 It means the state which is% or more.

In addition, the aggregate of the silica fine particles closely distributed around the organic fine particles is attached to the surface of the organic fine particles and / or a part of the silica fine particles constituting the aggregate is internally impregnated. (Hereafter, such an aggregate of silica fine particles is also referred to as adhering to the surface of the organic fine particles, etc.). The aggregates of the silica fine particles are attached to the surface of the organic fine particles, thereby utilizing the cohesive force acting between the aggregates of the silica fine particles attached to the surfaces of different organic fine particles, the different organic fine particles You can gather each other. For this reason, even if the addition amount of the organic fine particles is small, it is possible to form an uneven shape having a sufficient antiglare property.
Note that collecting organic particles does not mean that the organic particles are in close contact with each other, but the distance between the organic particles closest to the fold observed in the cross section of the optical layer is smaller than the average particle diameter of the particles. In this case, a plurality of aggregates of the silica fine particles are continuously connected in a row between the organic fine particles.
The aggregate of the silica fine particles attached to the surface of the organic fine particle can be easily confirmed by electron microscope observation of the cross section of the optical layer.

Examples of the method of attaching the aggregates of the silica fine particles to the surface of the organic fine particles include a method of hydrophilizing the surface of the organic fine particles, as described later.
Moreover, as a method of impregnating a part of the silica fine particles constituting the aggregate of the silica fine particles from the surface of the organic fine particles to the inside, for example, a method of reducing the degree of crosslinking of the organic fine particles And a method of using a solvent capable of swelling the organic fine particles in the composition for an optical layer described later.
It is preferable that the organic fine particles have adhesion of aggregates of the silica fine particles evenly on almost the entire surface.
The ratio of the aggregates of the silica fine particles adhering to the surface of the organic fine particles, occupied by the aggregates of the fine silica particles closely distributed around the organic fine particles, is preferably an electron microscope (TEM, STEM, etc. transmission type) In the thickness direction of the optical layer under a condition of 20,000 times magnification) when observed under a microscope, a region obtained by excluding the organic particles within the circumference of 200 nm from the organic particles. It is preferable that it is 50% or more by area ratio among the aggregate of the silica particle of these. If it is less than 50%, the effect of collecting the organic fine particles in the optical layer may be insufficient, and it may not be possible to form asperities having sufficient antiglare performance.

When a part of the silica fine particles constituting the aggregate of the silica fine particles is impregnated on the surface of the organic fine particles, the aggregate of the silica fine particles is impregnated to 500 nm from the surface of the organic fine particles. Is preferred. In order to impregnate the silica fine particles constituting the aggregate of the silica fine particles from the surface of the organic fine particles over 500 nm from the surface of the organic fine particles, it is necessary to cause the organic fine particles to swell excessively. As a result, uniform coating may not be obtained. In addition, in some cases, it is not possible to form the gentle concavo-convex shape described later on the surface of the optical layer.

The optical layer contains the aggregate of the fine particles of silica fine particles and the organic fine particles in such a specific state in the optical layer, whereby the optical layer is formed of a single fine particle or an unevenness formed thereof. The slope of the convex portion is gentler than the shape, resulting in a smooth shape. As a result, the optical laminate of the present invention can improve the bright room and dark room contrast while maintaining the antiglare property. Since the slope of the convex portion of the uneven shape formed on the surface of the optical layer is gentle and has a smooth shape, only the edge portion of the image reflected on the surface of the optical layer can be clearly seen. Antiglare is secured. Furthermore, the optical layer having such a concavo-convex shape can prevent the occurrence of stray light because it can eliminate large diffusion, and also can appropriately have a regular transmission part, so that it is an image with brightness, And it can be made to be excellent in the contrast in a bright room and a dark room (it has a blackish feeling).
This is presumed to be due to the following reasons.
That is, when the composition for an optical layer is applied and then dried to evaporate the solvent, the binder resin tends to follow the shape of the organic fine particles if the viscosity is low. Furthermore, although the binder resin shrinks in volume when it is cured, the organic fine particles do not shrink, so that only the binder resin shrinks, and the convex portion formed on the surface at the position corresponding to the organic fine particles is sharp It is easy to be inclined.
However, when the aggregate of the silica fine particles is densely distributed around the organic fine particles, the viscosity around the organic fine particles of the composition for the optical layer is increased, and when the solvent evaporates, the binder resin becomes the shape of the organic fine particles. It is difficult to follow, and the binder (consisting of binder resin and silica fine particles) in that portion is hard to cure and shrink, and as a result, the convex portion formed on the surface at the position corresponding to the organic fine particles tends to have a gentle slope. .
For this reason, it is estimated that the inclination angle of the concavo-convex shape (convex part) formed on the surface of the optical layer by the organic fine particles is gentler than the inclination angle of the concavo-convex shape (convex part) formed of the fine particles alone. Ru.

In addition, the organic fine particles are preferably fine particles having a relatively uniform particle diameter that mainly forms an uneven shape on the surface of the optical layer, and the aggregates of the silica fine particles are roughly dense in the optical layer as described above It is preferable that it is an aggregate which is distributed, and in the optical layer, the variation in particle diameter is relatively large. When the optical layer contains two kinds of fine particles having such a particle diameter relationship, in the optical laminate of the present invention, the particle diameter variation among the organic fine particles having the uniform particle diameter in the optical layer. It is possible to easily form a structure in which aggregates of silica fine particles having a large size are incorporated, and the above-described smooth uneven shape can be suitably formed on the surface of the optical layer.
Here, the above-mentioned "fine particles having relatively uniform particle sizes" means that the average particle size of the fine particles by weight average is MV, the cumulative 25% diameter is d25, and the cumulative 75% diameter is d75 (d75-d25) It means the case where / MV is 0.25 or less, and the above-mentioned "aggregate having a relatively large variation in particle diameter" means the case where (d75-d25) / MV exceeds 0.25. The 25% cumulative diameter refers to the particle diameter at 25% by mass counted from particles with a smaller particle diameter in the particle diameter distribution, and the 75% cumulative diameter similarly counts 75 mass. The particle size when it becomes%. In addition, the average particle diameter of microparticles | fine-particles by the said weight average, 25% of accumulation diameter, and 75% of accumulation diameter can be measured as a weight average diameter by a Coulter counter method.

In the optical layer, the organic fine particles and the silica fine particles preferably have a spherical shape in a single particle state. When the organic fine particle and the single particle of the silica fine particle are such spherical, when the optical layered body of the present invention is applied to an image display device, a display image with high contrast can be obtained.
In addition, a "spherical", for example, includes a true spherical shape, an elliptical spherical shape and the like, and has a meaning excluding so-called indeterminate form.

The organic fine particles are mainly fine particles that form the surface asperity shape of the optical layer, and are fine particles whose refractive index and particle diameter can be easily controlled. By including such organic fine particles, it becomes easy to control the size of the concavo-convex shape formed in the optical layer and the refractive index of the optical layer, and it is possible to control the antiglare property and to suppress the occurrence of glare and white blur. .

The organic fine particles are made of at least one material selected from the group consisting of acrylic resin, polystyrene resin, styrene-acrylic copolymer, polyethylene resin, epoxy resin, silicone resin, polyvinylidene fluoride resin and polytetrafluoroethylene resin. It is preferable that it is fine particles. Among them, styrene-acrylic copolymer fine particles are suitably used.

The organic fine particles are preferably subjected to surface hydrophilization treatment. The surface hydrophilization treatment of the organic fine particles enhances the affinity to the silica fine particles, and the aggregate of the silica fine particles can be attached to the surface of the organic fine particles. In addition, it is easy to densely distribute the aggregates of the silica fine particles around the organic fine particles.
The hydrophilization treatment is not particularly limited and may be a known method, for example, a method of copolymerizing a monomer having a functional group such as a carboxylic acid group or a hydroxyl group on the surface of the organic fine particles.
Generally, organic fine particles subjected to surface hydrophilization treatment can not be collected gently in the optical layer, so that sufficient uneven shape can not be formed on the surface of the optical layer and the antiglare performance is inferior. Become. However, in the present invention, the silica fine particles form aggregates and are coarsely contained in the optical layer, and the aggregates of the silica fine particles are densely distributed around the organic fine particles, so the surface is made hydrophilic. Even in the case of an optical layer containing treated organic fine particles, it is possible to form a desired asperity shape.

The content of the organic fine particles is preferably 0.5 to 10.0% by mass in the optical layer. When the amount is less than 0.5% by mass, the antiglare performance may be insufficient. When the amount is more than 10.0% by mass, a problem of white blur may occur, and the optical laminate of the present invention When it uses for an image display apparatus, it may be inferior to the contrast of a display image. A more preferable lower limit is 1.0% by mass, and a more preferable upper limit is 8.0% by mass.

The size of the organic fine particles is appropriately determined in accordance with the thickness of the optical layer and the like. For example, the average particle size is preferably 0.3 to 5.0 μm. If it is less than 0.3 μm, the dispersibility of the organic fine particles may not be controlled, and if it exceeds 5.0 μm, the unevenness of the surface of the optical layer may become large, which may cause a problem of surface glaring. A more preferable lower limit is 1.0 μm, and a more preferable upper limit is 3.0 μm.
The average particle diameter of the organic fine particles is preferably 20 to 60% of the thickness of the optical layer. If it exceeds 60%, the organic fine particles may protrude to the outermost surface of the coating layer, and the unevenness generated by the organic fine particles may be sharp. If it is less than 20%, sufficient uneven shape can not be formed on the surface of the optical layer, and the antiglare performance may be insufficient.
In addition, the average particle diameter of the said organic particulates can be measured as a weight average diameter by a Coulter counter method, when measuring by organic particulates independent. On the other hand, the average particle diameter of the organic fine particles in the optical layer is determined as a value obtained by averaging the maximum diameters of ten particles in transmission optical microscope observation of the optical layer. Alternatively, if this is not appropriate, diffused particles observed as an approximately equal particle diameter of any same kind in observation of an electron microscope (a transmission type such as TEM, STEM or the like is preferable) of a cross section passing near the particle center. The maximum particle diameter of the cross section is measured by selecting the number (the number of n is increased because it is unclear which section of the particle is the cross section), and the value is calculated as the average value. In order to judge all from an image, you may calculate by image analysis software.

Moreover, as thickness of the said optical layer, it is preferable that it is 2.0-7.0 micrometers. If the thickness is less than 2.0 μm, the surface of the optical layer may be easily scratched, and if it exceeds 7.0 μm, the optical layer may be easily broken. A more preferable range of the thickness of the optical layer is 2.0 to 5.0 μm. The thickness of the optical layer can be measured by cross-sectional microscope observation.

It is preferable that in the optical layer, the silica fine particles and the organic fine particles are dispersed in a binder resin.
As the binder resin, it is preferable to use a polyfunctional acrylate monomer containing no hydroxyl group in the molecule as a main material. The above-mentioned "the main component is a polyfunctional acrylate monomer having no hydroxyl group in the molecule" means that the content of the polyfunctional acrylate monomer having no hydroxyl group in the molecule is the largest among the raw material monomers of the binder resin. Do. Since the polyfunctional acrylate monomer containing no hydroxyl group in the molecule is a hydrophobic monomer, in the optical laminate of the present invention, the binder resin constituting the optical layer is preferably a hydrophobic resin. When the binder resin is mainly composed of a hydrophilic resin having a hydroxyl group, a solvent having high polarity (for example, isopropyl alcohol) to be described later hardly evaporates, and the silica fine particles hardly adhere to and / or impregnate the organic fine particles. Therefore, the aggregation proceeds with only the silica fine particles after that, and there is a possibility that a convex portion which deteriorates glare may be formed on the surface of the optical layer.

Examples of polyfunctional acrylate monomers containing no hydroxyl group in the molecule include pentaerythritol tetraacrylate (PETTA), 1,6-hexanediol diacrylate (HDDA), dipropylene glycol diacrylate (DPGDA), and tripropylene glycol diacrylate. Acrylate (TPGDA), PO modified neopentyl glycol diacrylate, tricyclodecane dimethanol diacrylate, trimethylolpropane triacrylate (TMPTA), trimethylolpropane ethoxy triacrylate, dipentaerythritol hexaacrylate (DPHA), pentaerythritol ethoxytetra Acrylate, ditrimethylolpropane tetraacrylate, etc. may be mentioned. Among them, pentaerythritol tetraacrylate (PETTA) is suitably used.

Moreover, as another binder resin, the thing of transparency is preferable, for example, it is preferable that ionizing radiation curable resin which is resin hardened | cured by an ultraviolet ray or an electron beam is hardened | cured by irradiation of an ultraviolet ray or an electron beam.
In the present specification, “resin” is a concept also including monomers, oligomers, polymers and the like unless otherwise stated.

Examples of the ionizing radiation-curable resin include compounds having one or more unsaturated bonds, such as compounds having a functional group such as acrylates. Examples of the compound having an unsaturated bond of 1 include ethyl (meth) acrylate, ethylhexyl (meth) acrylate, styrene, methylstyrene, N-vinylpyrrolidone and the like. Examples of compounds having two or more unsaturated bonds include trimethylolpropane tri (meth) acrylate, tripropylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, pentaerythritol tri (meth) acrylate and dipentaerythritol Hexa (meth) acrylate, 1,6-hexanediol di (meth) acrylate, neopentyl glycol di (meth) acrylate, trimethylolpropane tri (meth) acrylate, ditrimethylolpropane tetra (meth) acrylate, pentaerythritol tetra (meth) acrylate ) Acrylate, dipentaerythritol penta (meth) acrylate, tripentaerythritol octa (meth) acrylate, tetrapentaerythritol dec (meth) Acrylate, isocyanurate tri (meth) acrylate, isocyanurate di (meth) acrylate, polyester tri (meth) acrylate, polyester di (meth) acrylate, bisphenol di (meth) acrylate, diglycerin tetra (meth) acrylate, adamantyl di ( Polyfunctional compounds such as meta) acrylate, isoboronyl di (meth) acrylate, dicyclopentadi (meth) acrylate, tricyclodecane di (meth) acrylate and the like can be mentioned. In the present specification, "(meth) acrylate" refers to methacrylate and acrylate. In the present invention, as the above-mentioned ionizing radiation curable resin, one obtained by modifying the above-mentioned compound with PO, EO or the like can also be used.

In addition to the above compounds, polyester resins of relatively low molecular weight having unsaturated double bonds, polyether resins, acrylic resins, epoxy resins, epoxy resins, urethane resins, alkyd resins, spiroacetal resins, polybutadiene resins, polythiol polyene resins, etc. It can be used as an ionizing radiation curable resin.

The ionizing radiation curable resin is used in combination with a solvent-drying resin (a thermoplastic resin, etc., a resin which becomes a film only by drying the solvent added for adjusting the solid content at the time of coating). It can also be done. By using a solvent-drying resin in combination, it is possible to effectively prevent film defects on the application surface of the coating liquid when forming the optical layer.
The solvent-drying resin which can be used in combination with the ionizing radiation-curable resin is not particularly limited, and generally, a thermoplastic resin can be used.
It does not specifically limit as said thermoplastic resin, For example, styrene resin, (meth) acrylic resin, vinyl acetate resin, vinyl ether resin, halogen containing resin, alicyclic olefin resin, polycarbonate resin, polyester resin Examples thereof include resins, polyamide resins, cellulose derivatives, silicone resins and rubbers or elastomers. The thermoplastic resin is preferably non-crystalline and soluble in an organic solvent (in particular, a common solvent capable of dissolving a plurality of polymers and curable compounds). In particular, styrene resins, (meth) acrylic resins, alicyclic olefin resins, polyester resins, cellulose derivatives (cellulose esters and the like) and the like are preferable from the viewpoint of film forming property, transparency and weather resistance.

The optical layer may contain a thermosetting resin.
The thermosetting resin is not particularly limited, and examples thereof include phenol resin, urea resin, diallyl phthalate resin, melamine resin, guanamine resin, unsaturated polyester resin, polyurethane resin, epoxy resin, amino alkyd resin, and melamine-urea cocondensation. Resin, silicone resin, polysiloxane resin etc. can be mentioned.

The optical layer containing the silica fine particles, the organic fine particles and the binder resin is, for example, coated on a polyester substrate a composition for an optical layer containing the silica fine particles, the organic fine particles, the monomer component of the binder resin and the solvent. It can be formed by curing the coating film formed by drying by ionizing radiation irradiation or the like.

In the composition for an optical layer, in the composition, the above-mentioned fine particles of silica form the above-mentioned aggregates but are preferably in a uniformly dispersed state, and when the above-mentioned coating film is dried, Preferably, they are distributed and densely distributed around the organic fine particles. Unless the aggregates of the silica fine particles are uniformly dispersed in the composition for the optical layer, the aggregation proceeds excessively in the composition for the optical layer, and it becomes a huge aggregate of the silica fine particles. It is because it becomes impossible to form the optical layer which has the smooth uneven shape mentioned above.
Here, since the silica fine particles are materials capable of thickening the composition for the optical layer, by containing the silica fine particles, the sedimentation of the organic fine particles contained in the composition for the optical layer can be suppressed. . That is, it is speculated that the silica fine particles have a function to improve the pot life of the composition for an optical layer, as well as the function to promote the formation of a predetermined distribution of the organic fine particles and the aggregates of the silica fine particles described above.

The silica fine particles are uniformly dispersed as aggregates in the composition for an optical layer, and the aggregate of the silica fine particles in the coating is coarse and dense, and around the organic fine particles. As a method of making it densely distributed, for example, as a solvent to be added to the composition for an optical layer, there may be mentioned a method of containing a predetermined amount of a solvent having a high polarity and a high volatilization rate. By containing such a solvent having a high polarity and a high volatilization rate, it is possible to prevent excessive aggregation of the aggregates of the silica fine particles in the composition for an optical layer. On the other hand, when forming a coating film by applying and drying on the polyester substrate, the solvent having high polarity and high volatilization speed volatilizes before other solvents, so the composition at the time of coating film formation As a result, the aggregates of the silica fine particles are concentrated around the organic fine particles in the coating film, and the aggregates of the silica fine particles are also gathered together, so that the aggregates of the silica fine particles are coarse and dense, And, a densely distributed state can be formed around the organic fine particles.
In the present specification, “solvent having high polarity” means a solvent having a solubility parameter of 10 [(cal / cm ³ ) ^1/2 ] or more, and “solvent having high evaporation rate” means relative evaporation. It means a solvent with a speed of 150 or more. Therefore, the above-mentioned "polar solvent with high volatility rate" means a solvent that satisfies the requirements of both the "polar solvent" and the "volatile rate solvent".
As used herein, the solubility parameter is calculated by the method of Fedors. The method of Fedors is described, for example, in "SP value basics / application and calculation method" (Hideki Yamamoto, published by Information Technology Co., Ltd., 2005). In the Fedors method, the solubility parameter is calculated by the following equation.
Solubility parameter = [ΣE _coh / ΣV] ²
In the above formula, E _coh is a cohesive energy density and V is a molar molecular volume. Based on the _{E coh} and V were determined for each atom _group, by determining the? En _coh and ΣV is the sum of _{E coh} and V, it is possible to calculate the solubility parameter.
Further, in the present specification, the above-mentioned relative evaporation rate means the relative evaporation rate when the evaporation rate of n-butyl acetate is 100, and is the evaporation rate measured according to ASTM D3539-87, Calculated by Specifically, the evaporation time of n-butyl acetate under dry air at 25 ° C. and the evaporation time of each solvent are measured and calculated.
Relative evaporation rate = (time taken for 90 wt% of n-butyl acetate to evaporate) / (time taken for 90 wt% of the measurement solvent to evaporate) × 100

Examples of the solvent having a high polarity and a high volatilization rate include ethanol and isopropyl alcohol. Among them, isopropyl alcohol is preferably used.
Moreover, it is preferable that content of the isopropyl alcohol in the said solvent is 20 mass% or more in all the solvents. If it is less than 20% by mass, aggregates of silica fine particles may be generated in the composition for an optical layer. The content of the isopropyl alcohol is preferably 40% by mass or less.

As other solvents contained in the composition for the optical layer, for example, ketones (acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone etc.), ethers (dioxane, tetrahydrofuran etc.), aliphatic hydrocarbons (hexane etc.) Alicyclic hydrocarbons (cyclohexane etc.), aromatic hydrocarbons (toluene, xylene etc.), halogenated carbons (dichloromethane, dichloroethane etc.), esters (methyl acetate, ethyl acetate, butyl acetate etc.), alcohols (Eg, butanol, cyclohexanol, etc.), cellosolves (eg, methyl cellosolve, ethyl cellosolve), cellosolve acetates, sulfoxides (eg, dimethylsulfoxide), amides (eg, dimethylformamide, dimethylacetamide), etc., and mixtures thereof so It may be.

The composition for an optical layer preferably further contains a photopolymerization initiator.
The photopolymerization initiator is not particularly limited, and known ones may be used. Specific examples thereof include, for example, acetophenones, benzophenones, Michler's benzoyl benzoate, α-amyloxime ester, thioxanthones, and propio These include phenones, benzyls, benzoins, and acyl phosphine oxides. Further, it is preferable to use a mixture of photosensitizers, and specific examples thereof include n-butylamine, triethylamine, poly-n-butylphosphine and the like.

As the photopolymerization initiator, when the binder resin is a resin system having a radically polymerizable unsaturated group, acetophenones, benzophenones, thioxanthones, benzoin, benzoin methyl ether etc. may be used alone or in combination. preferable. When the binder resin is a resin system having a cationically polymerizable functional group, as the photopolymerization initiator, an aromatic diazonium salt, an aromatic sulfonium salt, an aromatic iodonium salt, a metallocene compound, a benzoin sulfonic acid ester, etc. It is preferable to use either alone or as a mixture.

The content of the photopolymerization initiator in the composition for an optical layer is preferably 0.5 to 10.0 parts by mass with respect to 100 parts by mass of the binder resin. If the amount is less than 0.5 parts by mass, the hard coat performance of the formed optical layer may be insufficient. If the amount is more than 10.0 parts by mass, the possibility of inhibiting the curing may also be obtained. Not desirable.

The content ratio (solid content) of the raw material in the composition for an optical layer is not particularly limited, but usually 5 to 70% by mass, particularly preferably 25 to 60% by mass.

In the composition for an optical layer, conventionally known dispersants, surfactants, antistatic agents, and silane cups can be used according to the purposes such as increasing the hardness of the optical layer, suppressing curing shrinkage, controlling the refractive index, etc. Ring agents, thickeners, anti-coloring agents, coloring agents (pigments, dyes), anti-foaming agents, leveling agents, flame retardants, UV absorbers, adhesion promoters, polymerization inhibitors, antioxidants, surface modifiers, A lubricant and the like may be added.
Examples of the leveling agent include silicone oil, a fluorine-based surfactant and the like, and preferably, a fluorine-based surfactant and the like containing a perfluoroalkyl group prevent the optical layer from becoming a Benard cell structure. It is preferable from When a resin composition containing a solvent is applied and dried, a surface tension difference or the like is generated between the surface and the inner surface of the coating in the coating, thereby causing a large number of convections in the coating. The structure generated by this convection is called a Benard cell structure, and causes problems such as wrinkles and coating defects in the formed optical layer.
Further, in the above Benard cell structure, the unevenness of the surface of the optical layer becomes too large to adversely affect white blur and glare. When the leveling agent as described above is used, this convection can be prevented, so that not only the uneven film having no defect or unevenness is obtained, but also adjustment of the uneven shape becomes easy.

The composition for an optical layer may be used as a mixture of photosensitizers, and specific examples thereof include n-butylamine, triethylamine, poly-n-butylphosophine and the like.

The method for preparing the composition for an optical layer is not particularly limited as long as the components can be uniformly mixed, and for example, known methods such as a paint shaker, a bead mill, a kneader, and a mixer can be used.

The method for applying the composition for an optical layer on a polyester substrate is not particularly limited, and examples thereof include spin coating, dipping, spraying, die coating, bar coating, roll coating, meniscus coating, and flexo coating. Known methods such as a printing method, a screen printing method, and a peel coater method can be mentioned.
After applying the composition for the optical layer by any of the above methods, it is conveyed to a heated zone to dry the coating formed and dried the coating by a variety of known methods to evaporate the solvent. Distribution state of aggregates of organic fine particles and silica fine particles by selecting solvent relative evaporation rate, solid content concentration, coating solution temperature, drying temperature, drying air velocity, drying time, solvent atmosphere concentration of drying zone, etc. Can be adjusted.
In particular, a method of adjusting the distribution state of the aggregates of the organic fine particles and the fine particles of silica by selecting the drying conditions is simple and preferable. The specific drying temperature is preferably 30 to 120 ° C., and the drying speed is preferably 0.2 to 50 m / s, and the organic fine particles can be appropriately adjusted within this range by performing the drying treatment once or plural times. And the distribution state of the aggregate of silica particles can be adjusted to a desired state.

In addition, as the irradiation method of ionizing radiation at the time of curing the coating film after the drying, for example, a light source such as an ultra high pressure mercury lamp, a high pressure mercury lamp, a low pressure mercury lamp, a carbon arc lamp, a black light fluorescent lamp, a metal halide lamp is used. The method is mentioned.
Moreover, as a wavelength of an ultraviolet-ray, a 190-380 nm wavelength range can be used. Specific examples of the electron beam source include various electron beam accelerators such as Cockcroft-Walt type, Bande graft type, Resonant transformer type, Insulated core transformer type, Linear type, Dynamitron type, and High frequency type.

Moreover, as another aspect of the optical layer, the inorganic fine particles are roughly distributed around the organic fine particles, and uniformly distributed in the optical layer other than the peripheral of the organic fine particles. Is preferred.
By controlling the inorganic fine particles and the organic fine particles to be in such a specific state, the uneven shape is formed more uniformly and uniformly as compared with the optical layer of the conventional optical laminate. An optical laminate provided with such an optical layer can suppress the occurrence of glare at an extremely high level while having good antiglare properties, and can obtain a display image excellent in high contrast .
The above-mentioned "the above-mentioned inorganic fine particles are roughly distributed around the organic fine particles" means that the thickness of the optical layer under the condition of 10,000 times magnification with an electron microscope (a transmission type such as TEM or STEM is preferable) The area ratio of the inorganic fine particles in the area excluding the organic fine particles within the circumference of 500 nm from the organic fine particles is defined as Mn when the cross section where the organic fine particles in the direction are observed is observed with a microscope. The area ratio of the inorganic fine particles in the region outside of the circumference outside 500 nm from the above is Mf, which means that Mf / Mn is 1.5 or more.
In addition, “uniformly distributed in the antiglare layer” means that the organic fine particles in the thickness direction of the optical layer have a magnification of 10,000 times with an electron microscope (a transmission type such as TEM or STEM is preferable). When the area ratio of the silica fine particles in the observation area of 5 μm square is measured for each cross section when observing 10 arbitrary cross sections from the non-observed part, the average value is M, and the standard deviation is S. , S / M ≦ 0.1.

In the optical layer according to the other aspect described above, the inorganic fine particles, the organic fine particles, the binder resin, the photopolymerization initiator, and the solvent may be the same as those described for the optical layer described above. In the optical layer according to the aspect of the present invention, the organic fine particles are preferably not surface-hydrophilized. If the organic fine particles are surface-hydrophilized, the affinity to the inorganic fine particles is too high, and it may be difficult to roughly distribute the inorganic fine particles around the organic fine particles.
Further, the method for producing the optical body according to the other aspect is not particularly limited as long as it can be controlled to contain the organic fine particles and the inorganic fine particles in the optical layer in the above-mentioned state. It can be manufactured by the manufacturing method of the layer.

Although it does not specifically limit as content of the said silica particle in the optical layer which concerns on the said another aspect, It is preferable that it is 1.0-10.0 mass% in the said optical layer. When the amount is less than 1.0% by mass, the organic fine particles described above may not be present so as to form a uniform uneven shape. When the amount exceeds 10.0% by mass, the viscosity of the composition for an optical layer is There is a risk that the coating suitability may deteriorate due to excessive rise. A more preferred lower limit is 3.0% by mass, and a more preferred upper limit is 8.0% by mass.

In the optical layer according to the other aspect, the content of the organic fine particles is preferably 1 to 50% by mass in solid content in the composition for an antiglare layer. When it is less than 1% by mass, the antiglare performance of the laminate to be produced may be insufficient, and when it exceeds 50% by mass, a problem of white blur may occur, and the produced laminate is used as an image. When it uses for a display apparatus, it may be inferior to the contrast of a display image. A more preferable lower limit is 5% by mass, and a more preferable upper limit is 20% by mass.

In the optical layer according to the other aspect, the size of the organic fine particles is appropriately determined according to the thickness of the antiglare layer to be formed, and for example, the average particle diameter is 0.3 to 6.0 μm. Is preferred. If it is less than 0.3 μm, the dispersibility of the organic fine particles may not be controlled, and if it exceeds 6.0 μm, the unevenness of the surface of the antiglare layer becomes large, which may cause surface glaring problems. A more preferable lower limit is 2.0 μm, and a more preferable upper limit is 4.0 μm.
The average particle size of the organic fine particles is preferably 20 to 90% of the thickness of the antiglare layer to be formed. If it exceeds 90%, the effect of the film thickness deviation on the asperity shape becomes strong, and the antiglare layer may be formed unevenly. If it is less than 20%, sufficient uneven shape can not be formed on the surface of the antiglare layer, and the antiglare performance may be insufficient.

Moreover, the uneven shape of the surface of the optical layer according to the other aspect divides the surface of the optical layer into 100 μm square measurement areas, and finds the arithmetic average roughness Sa in each measurement area, and the arithmetic average roughness Sa The ratio (Sq / Ma) of Ma to Sq is preferably 0.15 or less, where Ma is the average value of and Sq is the standard deviation of the arithmetic mean roughness Sa.
Since the resolution of the human eye is about 100 μm, if the variation in 100 μm square is large, distortion of the transmitted light is recognized by the human eye and observed as glare. Therefore, when the ratio of Ma to Sq (Sq / Ma) exceeds 0.15, the distortion of the transmitted light of the laminate of the present invention is recognized and observed as glare. The (Sq / Ma) is preferably 0.12 or less, and more preferably 0.10 or less.
In addition, it is preferable that the average value (Ma) of said Ra is 0.10 micrometer or more and 0.40 micrometer or less. If the thickness is less than 0.10 μm, the antiglare property of the laminate of the present invention may be insufficient. If the thickness exceeds 0.40 μm, the contrast of the laminate of the present invention may be deteriorated.
The arithmetic mean roughness Sa is a three-dimensional extension of the arithmetic mean roughness Ra, which is a two-dimensional roughness parameter described in JIS B0601: 1994. When the roughness curved surface is Z (x, y) and the size of the measurement area surface is Lx and Ly, the following equation (a) is calculated.
In the above formula (a), A = Lx × Ly is represented.
Further, assuming that the height at the position of the i-th point in the X-axis direction and the j-th point in the Y-axis direction is Zi, j, the arithmetic average roughness Sa is calculated by the following equation (b).
In the above equation (b), N represents a total score.
As a device for obtaining such arithmetic mean roughness Sa in three dimensions, a contact-type surface roughness meter or a non-contact-type surface roughness meter (for example, an interference microscope, a confocal microscope, an atomic force microscope, etc.) It can be mentioned. Among these, it is preferable to use an interference microscope in view of the simplicity of the measurement. Examples of such an interference microscope include “New View” series manufactured by Zygo.

In the optical laminate of the present invention, as described above, since the asperity shape is formed on the surface of the optical layer by the silica fine particles and the organic fine particles, the asperity shape can be made smooth. As the concavo-convex shape of the surface of the optical layer, specifically, the average interval of the concavities and convexities on the surface of the optical layer is Sm, the average inclination angle of the concavo-convex portion is θa, and the arithmetic average roughness of the concavities and convexities is Ra When the ten-point average roughness of the image is Rz, the antiglare property is secured by making only the edge portion of the captured image invisible clearly, and eliminating large diffusion to prevent stray light generation and regular transmission. It is preferable to satisfy the following equation from the viewpoint of obtaining an optical laminate having a bright image and excellent contrast in a bright room and a dark room by appropriately holding a part. If the angle θa, Ra, Rz is less than the lower limit, reflection of external light may not be suppressed in some cases. In addition, when θa, Ra, and Rz exceed the upper limit, the brightness of the image decreases due to the decrease of the regular transmission component, the bright room contrast decreases due to the increase of the diffuse reflection of external light, and the stray light from the transmitted image light increases. As a result, the dark room contrast may be reduced. In the configuration of the present invention, when Sm is less than the lower limit, there is a possibility that the control of aggregation becomes difficult. On the other hand, if Sm exceeds the upper limit, the fineness of the image can not be reproduced, and there is a possibility that a defect such as a large image may occur.
50 μm <Sm <600 μm
0.1 ° <θa <1.5 °
0.02 μm <Ra <0.25 μm
0.30 μm <Rz <2.00 μm

Moreover, the uneven | corrugated shape of the said optical layer is more preferably satisfy | filling a following formula from said viewpoint.
100 μm <Sm <400 μm
0.1 ° <θa <1.2 °
0.02 μm <Ra <0.15 μm
0.30 μm <Rz <1.20 μm
More preferably, the concavo-convex shape of the optical layer satisfies the following formula.
120 μm <Sm <300 μm
0.1 ° <θa <0.5 °
0.02 μm <Ra <0.12 μm
0.30 μm <Rz <0.80 μm
In the present specification, the above Sm, Ra and Rz are values obtained by the method according to JIS B 0601-1994, and θa is a surface roughness measuring device: SE-3400 Instruction manual (1995. 07 .20 revision) (Kosaka R & D Labs., Inc.), and as shown in FIG. 4, the sum of the heights of the protrusions present at the reference length L (h ₁ + h ₂ + h can be obtained by ₃ + ··· ⁼ + _{h n)} of the arctangent _{^{θa tan -1 {(h 1 +}} h 2 + h 3 + ··· + h n) / L}.
Such Sm, θa, Ra, Rz can be determined by measurement using, for example, a surface roughness measuring device: SE-3400 / manufactured by Kosaka Research Institute, Ltd.

The optical laminate of the present invention preferably has a total light transmittance of 85% or more. When it is less than 85%, when the optical laminate of the present invention is mounted on the surface of an image display, color reproducibility and visibility may be impaired. The total light transmittance is more preferably 90% or more, and still more preferably 91% or more.
In addition, the said total light transmittance can be measured by "HM-150" etc. by Murakami Color Research Laboratory Co., Ltd. according to JISK7361.

Further, the optical laminate of the present invention preferably has a total haze of less than 5.0%. The above-mentioned total haze is haze value (%) which measured the haze of the whole optical layered product with "HM-150" etc. made by Murakami Color Research Laboratory in accordance with JIS K-7136. The optical layer may consist of internal haze due to internal diffusion by the contained fine particles and external haze due to the uneven shape of the outermost surface, and the internal haze due to internal diffusion is preferably in the range of 0% or more and less than 5.0%. The range is more preferably 0% or more and less than 4.0%, and still more preferably 0% or more and less than 2.5%. The external haze of the outermost surface is preferably in the range of 0% or more and less than 2.0%, and more preferably in the range of 0% or more and less than 1.0%. In the reflection and / or transmission, when the light has an intensity at a diffusion angle of 1.0 degrees or more and less than 2.5 degrees, the internal haze and / or the external haze is most preferably 0%. If the above optical layer does not have a diffusion angle of 1.0 degree or more due to surface unevenness, the antiglare effect can not be seen, and if the diffusion due to internal diffusion does not have a diffusion degree of 1.0 degree or more, surface glare Is stronger. Here, “in the case of having an intensity at a diffusion angle of not less than 1.0 degrees and less than 2.5 degrees” means that the intensity of diffused light at every 0.1 degree was measured from a diffusion angle of 0 degrees to 2.4 degrees. It means that the total of the intensity of the diffused light of the diffusion angle of 1.0 degree to 2.4 degrees is 10% or more with respect to the total of the time.
In the optical layered body of the present invention, by using fumed silica as the silica fine particles, the internal haze and the external haze of the optical layer can be controlled independently. For example, by using fumed silica, since the average particle diameter of the fumed silica is small, the internal haze does not appear, and only the external haze can be adjusted. In addition, the internal haze is adjusted by controlling the ratio of the refractive index of the organic fine particles to the refractive index of the binder resin or changing the refractive index of the organic particle interface by impregnating the organic fine particles of the binder resin into the organic fine particles. can do.
Moreover, the said internal haze is calculated | required as follows.
On the surface of the optical layer of the antiglare film, the resin that forms the surface asperity has a refractive index equal to that of the resin that forms the surface asperity, or the resin whose refractive index difference is 0.02 or less The coating is applied so as to obtain a film thickness that can make the surface flat and flat, and after drying at 70 ° C. for 1 minute, it is cured by irradiation with 100 mJ / cm 2 of ultraviolet light. By this, the unevenness | corrugation in a surface is crushed and the film which became a flat surface is obtained. However, when the leveling agent or the like is contained in the composition forming the optical layer having the concavo-convex shape, when the resin applied to the surface of the optical layer is easily repelled and it is difficult to get wet, the surface of the optical layer is made in advance. Is soaked in a saponification treatment (2 mol / L NaOH (or KOH) solution for 3 minutes at 55 ° C, then washed with water, water droplets are completely removed with Kimwipe (registered trademark), etc., and then dried for 1 minute in a 50 ° C oven It is preferable to apply hydrophilic treatment according to
The film having a flat surface has no surface asperity, and thus has only an internal haze. The internal haze can be determined by measuring the total haze of this film in the same manner as the total haze in accordance with JIS K-7136.
Moreover, the said external haze can be calculated | required as (all the haze-internal haze).

The optical layered body of the present invention preferably has a low refractive index layer on the above-mentioned optical layer, since the occurrence of white blur can be more suitably prevented.
The low refractive index layer is a layer serving to lower the reflectance when light from the outside (for example, a fluorescent lamp, natural light, etc.) is reflected on the surface of the optical laminate. The low refractive index layer is preferably 1) a resin containing low refractive index particles such as silica or magnesium fluoride, 2) a fluorine resin which is a low refractive index resin, 3) a fluorine containing silica or magnesium fluoride 4) Any one of thin films of low refractive index substances such as silica and magnesium fluoride. As resins other than fluorine-based resins, the same resins as the binder resin constituting the optical layer described above can be used.
The above-mentioned silica is preferably hollow silica fine particles, and such hollow silica fine particles can be produced, for example, by the production method described in the example of JP-A-2005-099778.
The refractive index of these low refractive index layers is preferably 1.45 or less, particularly 1.42 or less.
In addition, the thickness of the low refractive index layer is not limited, but in general, it may be appropriately set within the range of about 30 nm to 1 μm.
In addition, although the low refractive index layer is effective as a single layer, it is also possible to appropriately provide two or more low refractive index layers for the purpose of adjusting a lower minimum reflectance or a higher lower reflectance. . When providing two or more low refractive index layers, it is preferable to make a difference in refractive index and thickness of each low refractive index layer.

As said fluorine resin, the polymeric compound or its polymer which contains a fluorine atom in a molecule | numerator at least can be used. The polymerizable compound is not particularly limited, but preferred is, for example, one having a curing reactive group such as a functional group curable by ionizing radiation and a polar group curable by heat. In addition, it may be a compound having these reactive groups at the same time. With respect to this polymerizable compound, the polymer does not have any reactive group as described above.

A wide variety of fluorine-containing monomers having an ethylenically unsaturated bond can be used as the polymerizable compound having a functional group that is cured by the ionizing radiation. More specifically, fluoroolefins (eg fluoroethylene, vinylidene fluoride, tetrafluoroethylene, hexafluoropropylene, perfluorobutadiene, perfluoro-2,2-dimethyl-1,3-dioxole etc.) may be exemplified. Can. As those having a (meth) acryloyloxy group, 2,2,2-trifluoroethyl (meth) acrylate, 2,2,3,3,3-pentafluoropropyl (meth) acrylate, 2- (perfluorobutyl) ) Ethyl (meth) acrylate, 2- (perfluorohexyl) ethyl (meth) acrylate, 2- (perfluorooctyl) ethyl (meth) acrylate, 2- (perfluorodecyl) ethyl (meth) acrylate, α-trifluoro (Meth) acrylate compounds having a fluorine atom in the molecule such as methyl methacrylate and α-trifluoroethyl methacrylate; fluoroalkyl groups having 1 to 14 carbon atoms having at least 3 fluorine atoms in the molecule, fluoro A cycloalkyl group or a fluoroalkylene group, and at least two There are also fluorine-containing polyfunctional (meth) acrylic acid ester compounds having an acryloyloxy group and the like.

Preferred as the above-mentioned thermosetting thermosetting polar group are, for example, hydrogen bond-forming groups such as hydroxyl group, carboxyl group, amino group and epoxy group. These are excellent not only in adhesion with the coating film but also in affinity with inorganic ultrafine particles such as silica. Examples of the polymerizable compound having a thermosetting polar group include 4-fluoroethylene-perfluoroalkyl vinyl ether copolymer; fluoroethylene-hydrocarbon-based vinyl ether copolymer; epoxy, polyurethane, cellulose, phenol, polyimide and the like The fluorine-modified products of each resin and the like can be mentioned.
Examples of the polymerizable compound having both the functional group curable by ionizing radiation and the polar group curable by heat include partially or completely fluorinated alkyl, alkenyl, aryl esters, fully or partially fluorinated vinyl ethers of acrylic or methacrylic acid Or partially fluorinated vinyl esters, fully or partially fluorinated vinyl ketones, etc. can be exemplified.

Moreover, as a fluorine resin, the following can be mentioned, for example.
A monomer containing at least one fluorine-containing (meth) acrylate compound of the polymerizable compound having an ionizing radiation-curable group, or a polymer of a monomer mixture; at least one kind of the fluorine-containing (meth) acrylate compound and methyl (meth) Copolymers with fluorine atom-free (meth) acrylate compounds such as acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate and 2-ethylhexyl (meth) acrylate; fluoroethylene Fluorine-containing compounds such as vinylidene fluoride, trifluoroethylene, chlorotrifluoroethylene, 3,3,3-trifluoropropylene, 1,1,2-trichloro-3,3,3-trifluoropropylene, hexafluoropropylene Homopolymers of monomers or Copolymer such as. A silicone-containing vinylidene fluoride copolymer in which a silicone component is contained in these copolymers can also be used. As the silicone component in this case, (poly) dimethylsiloxane, (poly) diethyl siloxane, (poly) diphenyl siloxane, (poly) methyl phenyl siloxane, alkyl modified (poly) dimethylsiloxane, azo group-containing (poly) dimethylsiloxane, Dimethyl silicone, phenyl methyl silicone, alkyl / aralkyl modified silicone, fluoro silicone, polyether modified silicone, fatty acid ester modified silicone, methyl hydrogen silicone, silanol group containing silicone, alkoxy group containing silicone, phenol group containing silicone, methacryl modified silicone, acrylic Modified silicone, amino modified silicone, carboxylic acid modified silicone, carbinol modified silicone, epoxy modified silicone, mercapto modified silicone Over emissions, fluorine-modified silicones, polyether-modified silicone and the like. Among them, those having a dimethylsiloxane structure are preferable.

Furthermore, non-polymers or polymers comprising the following compounds can also be used as the fluorine-based resin. That is, a fluorine-containing compound having at least one isocyanato group in the molecule is reacted with a compound having in the molecule at least one functional group that reacts with the isocyanato group such as an amino group, a hydroxyl group or a carboxyl group. Compounds obtained; compounds obtained by reacting a fluorine-containing polyol such as fluorine-containing polyether polyol, fluorine-containing alkyl polyol, fluorine-containing polyester polyol, fluorine-containing ε-caprolactone modified polyol, and a compound having an isocyanate group It can be used.

Moreover, the binder resin as described in the said optical layer can also be mixed and used with the polymeric compound and polymer which have an above-described fluorine atom. Furthermore, various additives and solvents can be used as appropriate in order to improve the coating property and impart antifouling properties, and a curing agent for curing reactive groups and the like.

In the formation of the low refractive index layer, the viscosity of the composition for the low refractive index layer formed by adding a low refractive index agent, a resin and the like is preferably 0.5 to 5 mPa · s (25 ° C.) which can obtain preferable coatability. It is preferable to set it as the thing of the range of 0.7-3 mPa * s (25 degreeC) preferably. It is possible to realize an antireflective layer excellent in visible light, to form a thin film uniform and free from application unevenness, and to form a low refractive index layer which is particularly excellent in adhesion.

The curing means of the resin may be similar to those described for the optical layer described above. When a heating means is used for the curing treatment, it is preferable that a thermal polymerization initiator which generates, for example, a radical to start polymerization of the polymerizable compound is added to the fluorine-based resin composition by heating.

The layer thickness (nm) d _A of the low refractive index layer is expressed by the following formula (3):
d _A = mλ / (4 n _A ) (3)
(In the above formula,
n _A represents the refractive index of the low refractive index layer,
m represents a positive odd number, preferably 1;
λ is the wavelength, preferably in the range 480-580 nm)
It is preferable that the

Further, in the present invention, the low refractive index layer has the following formula (4):
_{120 <n A d A <145} (4)
It is preferable in terms of reducing the reflectance that

The optical laminate of the present invention is also of other layers (antistatic layer, antifouling layer, adhesive layer, other hard coat layer, etc.) as needed, as long as the effects of the present invention are not impaired. One or two or more layers can be formed as appropriate. Among them, it is preferable to have at least one of the antistatic layer and the antifouling layer. As these layers, the same ones as known antireflective laminates can be adopted.

The optical laminate of the invention preferably has a contrast ratio of 80% or more, more preferably 90% or more. When it is less than 80%, when the optical laminate of the present invention is mounted on the display surface, the dark room contrast may be inferior and the visibility may be impaired. In the present specification, the contrast ratio is a value measured by the following method.
That is, using a cold cathode tube light source provided with a diffusion plate as a back light unit, using two polarizing plates (AMN-3244TP manufactured by Samsung Co., Ltd.), when the polarizing plates are installed in parallel Nicol the _{L max} luminance values divided by the brightness of _{L min} of light passing through when installed in a cross nicol state with _(L max _{/ L min)} to the contrast, the contrast of the optical stack (polyester substrate + optical layer, etc.) A value (L ₁ / L ₂ ) × 100 (%) obtained by dividing (L ₁ ) by the contrast (L ₂ ) of the polyester substrate is taken as a contrast ratio.
In addition, the measurement of the said brightness | luminance is performed in a dark room. For the measurement of the luminance, a color luminance meter (BM-5A manufactured by Topcon Co., Ltd.) is used, and the measurement angle of the color luminance meter is set at 1 ° and measured with a visual field of 5 mm on the sample. In addition, the amount of light of the backlight is set so that the luminance is 3600 cd / m ² when two polarizing plates are set in parallel nicols in the state where the sample is not set.

The optical laminate of the present invention is produced by forming an optical layer on the above-mentioned optical control layer, using, for example, a composition for an optical layer containing silica fine particles, organic fine particles, a monomer component of a binder resin and a solvent. can do.
With regard to the composition for an optical layer and the method of forming an optical layer, the same materials and methods as those described as the method of forming an optical layer in the above-described optical laminate may be mentioned.

The optical layered body of the present invention can be made into a polarizing plate by providing the optical layered body according to the present invention on the surface of the polarizing element on the side opposite to the side on which the optical layer is present.

The polarizing element is not particularly limited. For example, a polyvinyl alcohol film, a polyvinyl formal film, a polyvinyl acetal film, an ethylene-vinyl acetate copolymer-based saponified film, and the like which are dyed with iodine or the like and stretched can be used. In the lamination process of the polarizing element and the antiglare film of the present invention, it is preferable to perform a saponification process on the polyester substrate. By the saponification treatment, the adhesion is improved and an antistatic effect can be obtained.

The present invention is also an image display device comprising the above-described optical laminate of the present invention or the above-mentioned polarizing plate.
The liquid crystal display (LCD), which is a typical example of the above, comprises a transmissive display and a light source device for irradiating the transmissive display from behind. When the image display device of the present invention is an LCD, the optical laminate or polarizing plate of the present invention is formed on the surface of the transmissive display.

When the present invention is a liquid crystal display device having the above optical laminate, the light source of the light source device is irradiated from the lower side of the optical laminate. A retardation plate may be inserted between the liquid crystal display element and the polarizing plate. An adhesive layer may be provided between each layer of the liquid crystal display device as necessary.

Here, in the case where the present invention is a liquid crystal display device having the above-mentioned optical laminate, the above-mentioned optical laminate is composed of the slow axis of the optical laminate and the above-mentioned polarizing plate (polarizing plate installed on the viewing side of liquid crystal cell). By setting the angle formed with the absorption axis to 45 ° ± 15 °, good visibility can be obtained even when the liquid crystal display device is observed through a polarizing plate such as sunglasses.
Further, in the case where the present invention is a liquid crystal display device having the above optical laminate, the above optical laminate absorbs the slow axis of the optical laminate and the above polarizing plate (polarizing plate disposed on the viewing side of the liquid crystal cell). More preferably, the angle formed with the axis is 0 ° ± 30 ° or 90 ° ± 30 °. When the angle between the slow axis of the optical laminate and the absorption axis of the polarizing plate is in the above range, it is possible to extremely highly suppress the occurrence of zygosity unevenness in the display image of the liquid crystal display device of the present invention. . Although this reason is not clear, it is thought that it is based on the following reasons.
That is, in an environment free from extraneous light and fluorescent light (hereinafter, such environment is also referred to as “dark place”), absorption of the slow axis of the optical laminate of the liquid crystal display device of the present invention and the polarizing plate The angle formed with the axis can suppress the occurrence of rainbow unevenness regardless of any angle. However, in an environment with external light or fluorescent light (hereinafter, such an environment is also referred to as “bright place”), the external light or fluorescent light only has a continuous broad spectrum. Therefore, if the angle between the slow axis of the optical laminate and the absorption axis of the polarizing plate is not in the above range, uneven streaks will occur and the display quality will deteriorate.
Furthermore, since the light of the backlight transmitted through the color filter is only limited to one having a continuous broad spectrum, the angle between the slow axis of the optical laminate and the absorption axis of the polarizing plate must be within the above range. It is estimated that the display quality is lowered due to the occurrence of the uneven streaks.

In the liquid crystal display device of the present invention, the backlight source is not particularly limited, but a white light emitting diode (white LED) is preferable.
The white LED is an element that emits white light by combining a phosphor type, that is, a light emitting diode that emits blue light or ultraviolet light using a compound semiconductor and the phosphor. Above all, a white light emitting diode composed of a light emitting element in which a blue light emitting diode using a compound semiconductor and an yttrium aluminum garnet yellow phosphor are combined has a continuous and wide emission spectrum, thereby improving the rainbow unevenness It is suitable as the above-mentioned back light source in the present invention because it is effective in the above and is excellent also in luminous efficiency. In addition, since white LEDs with low power consumption can be widely used, energy saving can be achieved.

The plasma display (PDP), which is the above-mentioned image display device, has a front surface glass substrate (with electrodes formed on the front surface) and a rear surface glass substrate (electrode and Micro grooves are formed on the surface, and red, green and blue phosphor layers are formed in the grooves). When the image display device of the present invention is a PDP, the above-described optical laminate may be provided on the surface of the surface glass substrate or the front plate (glass substrate or film substrate).

The above image display device deposits zinc sulfide, which emits light when a voltage is applied, and a diamine-like substance: a light emitter on a glass substrate and controls the voltage applied to the substrate to perform display, or converts an electrical signal into light. Or a CRT that produces an image visible to human eyes. In this case, the above-described optical laminate of the present invention is provided on the surface of each image display apparatus as described above or the surface of its front plate.
Moreover, the optical laminated body of this invention can also be used conveniently for the image display surface in a touch panel.

The optical layered body of the present invention having the above-described structure can suppress the occurrence of glare and has excellent luminance and can prevent a decrease in contrast.
Therefore, the optical laminate of the present invention is an image display in an image display device such as a liquid crystal display (LCD), a plasma display (PDP), an organic / inorganic electroluminescent display (LED), electronic paper, ELD, CRT or a touch panel It can be used suitably for the surface.

Sectional drawing which showed typically a part of optical control layer in the optical laminated body of this invention. It is a perspective view which shows typically an example of the optical laminated body of this invention. It is a perspective view which shows typically another example of the optical laminated body of this invention. It is explanatory drawing of the measuring method of (theta) a. It is a cross-sectional microscope picture of the optical control layer which concerns on an Example. (A)-(d) is explanatory drawing of an active energy irradiation process. It is explanatory drawing of an active energy irradiation process.

The present invention will be described in more detail by way of the following Examples and Comparative Examples, but the present invention is not limited to only these Examples and Comparative Examples.
In the following description, "part" or "%" is on a mass basis unless otherwise noted.

Example 1
(Composition for optical control layer 1)
High refractive index resin (full orange acrylate, refractive index: 1.62 50 parts by mass low refractive index resin (polypropylene glycol diacrylate, refractive index: 1.45)
50 parts by weight Photopolymerization initiator (1-hydroxy-cyclohexyl-phenyl-ketone) 4 parts by weight

(Preparation of Optical Control Layer 1)
The composition for the optical control layer 1 of the above composition was prepared, and applied to a light transmitting PET substrate having a thickness of 100 μm so that the film thickness after curing was 100 μm to form a coating film. Then, a light transmitting PET substrate having a thickness of 100 μm was laminated on the coating.
From the top of the light transmitting PET substrate, ultraviolet rays of parallel light were irradiated for 30 seconds at 5 mW / cm ² in the direction perpendicular to the coating surface. The PET on both sides was peeled off from the coating to obtain an optical control layer 1. When the cross section which cut the optical control layer 1 in the surface perpendicular | vertical to a film surface was observed with the optical microscope, as shown in FIG. 5, the columnar structure continuous from one surface to the other surface was formed. In addition, observation of the cross section was performed in the state before peeling PET of both surfaces.

(Composition for optical layer 1)
Pentaerythritol triacrylate 38 parts by mass EO modified triacrylate isocyanurate 22 parts by mass Photopolymerization initiator (1-hydroxy-cyclohexyl-phenyl-ketone) 5 parts by mass silicone leveling agent 0.1 parts by mass translucent particles (spherical poly) Acrylic-styrene copolymer; average particle diameter 3.5 μm, refractive index 1.525) 12 parts by mass inorganic ultrafine particles (silica with reactive functional group introduced on the surface, solvent MIBK, solid content 30%, average primary particles Diameter 12 nm) 120 parts by mass Solvent (toluene) 135 parts by mass

(Preparation of Optical Layer 1)
The composition 1 for an optical layer of the above composition is prepared, and the composition 1 for an optical layer is applied to a thickness of 5 μm after curing as a transparent substrate layer on a TAC substrate having a thickness of 80 μm, 70 After drying in an oven at 60 ° C. for 60 seconds, ultraviolet rays of non-parallel light were irradiated so as to give an irradiation amount of 120 mJ / cm ² to cure the coating, thereby obtaining an optical layer 1 having an uneven shape on the surface.

The optical control layer 1 was bonded to the surface of the transparent base material layer opposite to the surface on which the optical layer 1 is formed via a transparent adhesive, to produce an optical laminate according to Example 1.

(Example 2)
(Production of Optical Control Layer 2)
An optical control layer 2 was produced in the same manner as the optical control layer 1 except that the film thickness after curing was 200 μm.
An optical laminate according to Example 2 was produced in the same manner as Example 1 except that the optical control layer 2 was used instead of the optical control layer 1.

(Comparative example 1)
(Composition for optical control layer 3)
Pentaerythritol triacrylate 100 parts by mass Photopolymerization initiator (1-hydroxy-cyclohexyl-phenyl-ketone) 3 parts by mass Silicone based leveling agent 0.1 parts by mass Translucent particles (spherical melamine particles, average particle diameter 1.2 μm, Refractive index 1.66) 7.5 parts by mass Solvent (toluene) 130 parts by mass

(Preparation of Optical Control Layer 3)
A composition for optical control layer 3 of the above composition is prepared, and applied as a light transmitting substrate on a TAC substrate having a thickness of 80 μm so that the film thickness of the composition for optical control layer 3 is 20 μm after curing. The coating film is formed, and the coating film is dried in an oven at 70 ° C. for 60 seconds, and then the non-parallel light ultraviolet rays are irradiated so that the irradiation amount becomes 120 mJ / cm ² to cure the coating film. Control layer 3 (diffusion film) was obtained.

Optical lamination according to Comparative Example 1 in the same manner as in Example 1 except that the optical control layer 3 is bonded to the surface of the optical layer 1 opposite to the surface on which the concavo-convex shape is formed, via the transparent adhesive. It was a body.

(Comparative example 2)
(Composition for optical layer 2)
Pentaerythritol triacrylate 90 parts by mass acrylic polymer (molecular weight 75,000) 10 parts by mass Photopolymerization initiator (1-hydroxy-cyclohexyl-phenyl-ketone) 3 parts by mass silicone-based leveling agent 0.1 parts by mass translucent particles ( Spherical polystyrene particles; particle size 3.5 μm, refractive index 1.59 12 parts by weight solvent 1 (toluene) 145 parts by weight solvent 2 (cyclohexanone) 60 parts by weight

(Preparation of Optical Layer 2)
The composition 2 for optical layers of the above composition is prepared, and it is applied as a light transmitting substrate on a TAC substrate of 80 μm thickness so that the film thickness of the composition 2 for optical layers becomes 4.5 μm after curing. The film is dried in an oven at 70 ° C. for 60 seconds, and then irradiated with non-parallel light ultraviolet rays so that the irradiation dose is 120 mJ / cm ² to cure the coating film to obtain the optical layer 2 having an uneven shape on the surface. The
A laminate in which the optical layer 2 was provided on the obtained TAC substrate was used as an optical laminate according to Comparative Example 2.

The following evaluation was performed about the optical laminated body obtained by the Example and the comparative example. The results are shown in Table 1.

(Giratsuki)
In each of the optical laminates obtained in Examples and Comparative Examples, a surface on which the optical layer of the optical laminate is not formed, and a glass surface on which a black matrix (glass thickness 0.7 mm) equivalent to 350 ppi is not formed. And a transparent adhesive to prepare a sample.
Glare was generated in a pseudo manner by placing a white surface light source (LIGHTBOX manufactured by HAKUBA, average brightness: 1000 cd / m ² ) on the black matrix side of the sample thus obtained.
This was photographed from the optical laminate side with a CCD camera (KP-M1, C-mount adapter, close-up ring; PK-11A Nikon, camera lens; 50 mm, F1.4s NIKKOR). The distance between the CCD camera and the optical stack was 250 mm, and the focus of the CCD camera was adjusted to fit the optical stack. Images taken with a CCD camera were loaded into a personal computer and analyzed as follows using image processing software (ImagePro Plus ver. 6.2; manufactured by Media Cybernetics).

First, an evaluation site of 200 × 160 pixels was selected from the captured image, and converted to 16-bit gray scale at the evaluation site. Next, a low pass filter was selected from the emphasis tab of the filter command, and a filter was applied under the condition of “3 × 3, number of times 3, strength 10”. This removed the component derived from the black matrix pattern.
Next, flattening was selected, and shading correction was performed under the conditions of “background: dark, object width 10”.
Next, contrast enhancement was performed with "contrast: 96, brightness: 48" in the contrast enhancement command.
The resulting image was converted to 8-bit gray scale, and the glare was quantified by calculating the variation of the value for each pixel for 150 × 110 pixels among them as a standard deviation value. It can be said that the smaller the glaring value, the smaller the glaring value is.

(Contrast ratio)
In the measurement of the contrast ratio, when a cold cathode tube light source is provided with a diffusion plate as a backlight unit, two polarizing plates (AMN-3244TP manufactured by Samsung Co., Ltd.) are used, and the polarizing plates are installed in parallel nicol When the optical layered body according to the example and the comparative example is placed on the outermost surface by dividing L _max of the luminance of light passing through by L _min of the luminance of light passing through when disposed in cross nicol contrast _{(L 1),} only the light transmitting substrate obtains a contrast _{(L 2)} when placed on the outermost _surface, the contrast ratio by calculating _{(L 1 / L 2) ×} 100 (%) Was calculated.
The luminance was measured using a color luminance meter (BM-5A manufactured by Topcon Corporation) in a dark room environment where the illuminance was 5 Lx or less. The measurement angle of the color luminance meter was set to 1 °, and was measured from the vertical direction on the sample in a field of view of 5 mm. The amount of light of the backlight was set so that the brightness was 3600 cd / m ² when two polarizing plates were set in parallel nicols without a sample set.

(Transmitted light intensity)
The transmitted light intensities of the optical laminates obtained in Examples and Comparative Examples were measured as follows.
Using a variable angle photometer (GC-5000L, manufactured by Nippon Denshoku Kogyo Co., Ltd.), set the light source angle to 0 degree and the sensitivity setting to 1000 in transmission measurement, and the opposite side to the surface on which the optical layer is formed The sample is placed with the surface of the light source facing the light source, and the intensity of the transmitted light of the optical laminate is scanned within the range of -40 ° to + 40 °, ± 5 °, ± 10 °, ± 20 ° and The light intensity at ± 40 degrees was measured. The average of the light intensity value at +5 degrees and the light intensity value at -5 degrees was taken as the light intensity at 5 degrees. It calculated similarly about 10 degrees, 20 degrees, and 40 degrees. Then, T5 / T10 and T20 / T40 were calculated. The value of the light intensity is a relative value when the light intensity at 0 degree when the sample is not set is 100000.

The optical laminate according to the example had an optical control layer in which a columnar structure was formed continuously from one surface to the other surface, and therefore the glare was small and the contrast ratio was excellent. On the other hand, in the optical laminate according to Comparative Example 1, no columnar structure was formed continuously from one surface to the other surface in the optical control layer, and translucent fine particles were dispersed in the resin component. Moreover, the optical laminated body which concerns on the comparative example 2 was not provided with the optical control layer. Both of the comparative examples had light diffusivity by conventional particles, and thus both the glare and the contrast ratio were inferior to those of the optical laminate according to the example.

The optical laminate of the present invention can suppress the occurrence of glare and has excellent luminance and can prevent the reduction in contrast.

10, 20, 30 Optical control layer 11, 21, 31 Low refractive index area 12, 22, 32 High refractive index area 50 Irradiated light 60 Parallel light 101 Coating layer 102 Process sheet 125 Linear light source 202 Point light source 204 Lens 200 (200a 200 b) Irradiated light collimating member 210 Light shielding member 210 a Plate member 210 b Cylindrical member

Claims (7)

An optical laminate comprising an optical control layer and an optical layer having an uneven shape on the surface,
The optical control layer has a low refractive index region and a high refractive index region having a refractive index larger than that of the low refractive index region.
An optical laminated body, wherein the low refractive index area and the high refractive index area are continuously provided in a columnar shape from one surface of the optical control layer to the other surface. The optical laminate according to claim 1, wherein the low refractive index region has a refractive index of 1.40 to 1.50 and the high refractive index region has a refractive index of 1.50 to 1.65. The shortest distance between adjacent low refractive index regions and / or the shortest distance between adjacent high refractive index regions is 0.1 to 15 μm at the optical layer side interface of the optical control layer or the interface opposite to the optical layer side The optical laminated body of Claim 1 or 2. When light is incident from the normal direction of one surface of the optical control layer and the transmitted light intensity is measured, the transmitted light intensity at a diffusion angle of 5 ° is T5, and the transmitted light intensity at a diffusion angle of 10 ° is T10, a diffusion angle 4. The optical laminate according to claim 1, wherein the transmitted light intensity at 20 ° is T20, and the transmitted light intensity at a diffusion angle of 40 ° is T40.
T5 / T10 ≦ 5 (1)
T20 / T40 ≧ 50 (2) In the optical layer having the concavo-convex shape on the surface, the average spacing of the concavities and convexities on the surface is Sm, the average inclination angle of the concavo-convex portion is θa, the arithmetic mean roughness of concavities and convexities is Ra, and the ten-point mean roughness of concavities and convexities is Rz The optical laminate according to claim 1, 2, 3 or 4, which satisfies the following formula when it is formed.
50 μm <Sm <600 μm
0.1 ° <θa <1.5 °
0.02 μm <Ra <0.25 μm
0.30 μm <Rz <2.00 μm The optical layer having a concavo-convex shape on the surface contains silica fine particles, organic fine particles, and a binder resin, and the concavo-convex shape on the surface is formed by the silica fine particles and the organic fine particles. Or the optical laminated body of 5 statement. An image display apparatus comprising the optical laminate according to any one of claims 1, 2, 3, 4, 5 or 6.