JP7326734B2 - OPTICAL LAMINATED BODY, METHOD FOR MANUFACTURING OPTICAL LAMINATED BODY, LAMINATED MEMBER, AND DISPLAY DEVICE - Google Patents

Description

The present invention relates to an optical layered body, a method for producing the optical layered body, a layered member, and a display device.

In display devices such as mobile information terminal equipment, PC monitors, and TV monitors, an anti-glare film is installed on the viewer side of the display element for the purpose of preventing the reflection of external light. There is something. As the antiglare film, there is known a film in which an antiglare layer containing a binder and translucent fine particles and having an uneven surface is formed on a transparent support.
For example, in Patent Document 1, an antiglare layer containing a binder and translucent fine particles is provided on a support, and the average particle size of the translucent fine particles is 3 μm or more and 15 μm or less. The content of the optical fine particles is 0.1% by mass or more and 1.0% by mass or less with respect to the total solid content of the antiglare layer, and the translucent fine particles are grounded on the support-side interface of the antiglare layer to transmit light. This document discloses an optical film in which there are substantially no multi-tiered layers of antiglare particles in the film thickness direction of the antiglare layer. It is described that the optical film has both good black reproducibility and antiglare properties, is free from uneven interference and point defects due to coarse particles, and has excellent adhesion to the antiglare layer.
The anti-glare layer comprises a layer made of a coating composition containing a binder and light-transmitting fine particles and a layer (overcoat layer) made of a coating composition containing the binder but not light-transmitting fine particles. It is also disclosed that it can be formed by

Japanese Unexamined Patent Application Publication No. 2011-186008

2. Description of the Related Art In recent years, in mobile information terminal equipment equipped with a touch panel, development of an anti-glare member that can replace the cover glass forming the outermost surface of the touch panel has been underway. However, Patent Document 1 does not disclose such an antiglare member.
The application of the antiglare optical film disclosed in Patent Document 1 is a protective film for a polarizing film used in a liquid crystal TV, and an antiglare film used by adhering to a cover glass of a display surface. On the other hand, the cover glass substitute member constituting the outermost surface of the touch panel needs to have sufficient scratch resistance to withstand repeated use in applications where the display screen is operated by touching with a finger or a touch pen.

Further, when an overcoat layer is provided on a layer containing a binder and light-transmitting fine particles as in the antiglare layer of the antiglare optical film disclosed in Patent Document 1, the antiglare property is reduced accordingly. . However, when the antiglare property is increased, there is a problem that the image sharpness is lowered.
Among display devices, improvement of image quality is prioritized in TV monitors, and image clarity is particularly important when the screen is viewed from a long distance with a wide viewing angle. Also, since TV monitors are mainly used indoors, antiglare properties may be imparted to the extent that high image quality can be maintained. On the other hand, in the case of a mobile type information terminal equipped with a touch panel, the touch panel is operated while looking at the display screen at hand, so the image when viewed from a distance of about 30 cm (clear vision distance) from the display screen It is most important that the is clear. Furthermore, since mobile information terminal equipment is frequently used outdoors, a high level of anti-glare performance is essential to reduce the reflection of external light. However, performance was not sufficient with the adhesive film.

The present invention has been made under such circumstances, and the outermost surface of the touch panel, which has excellent antiglare properties and scratch resistance, and has excellent image clarity from near the clear vision distance when applied to a display device. An object of the present invention is to provide an optical layered body suitably used as a constituent antiglare member, a method for producing the optical layered body, and a layered member and a display device having the optical layered body.

The inventors of the present invention have made intensive studies to solve the above problems, and found that an optical layered body having a resin layer containing a binder resin and organic particles on at least one surface of a transparent substrate, wherein the resin layer has a predetermined configuration. Furthermore, the inventors have found that an optical layered body that satisfies a predetermined transmission image clarity can solve the above problems, and have completed the present invention.
That is, the present invention provides an optical layered body, a method for producing the optical layered body, a layered member, and a display device according to the following [1] to [4].

[1] An optical laminate having a resin layer containing a binder resin and organic particles on at least one surface of a transparent substrate, wherein the resin layer has an uneven shape on its upper surface, and The organic particles are not exposed and the binder resin present on the upper surface side of the organic particles in the resin layer has a thickness of 0.5 μm or more, and the thickness of the resin layer is 0.5 μm or more when the resin layer is observed from the upper surface. The number of the organic particles contained in the range of 1 mm × 0.1 mm is 20 or more, and the transmitted image definition with an optical comb width of 2.0 mm, measured in accordance with JIS K7374:2007, is 20.0. ˜55.0% optical laminate.
[2] A laminate member comprising the optical laminate according to [1] above and a polarizing element.
[3] An antiglare resin layer is formed on the transparent substrate using a coating liquid containing the binder resin or its precursor and the organic particles, and then the binder resin or the binder resin is formed on the antiglare resin layer. The optical lamination according to [1] above, comprising a step of forming a surface resin layer using a coating liquid containing a precursor and not containing the organic particles, and forming the resin layer on the transparent substrate. body manufacturing method.
[4] A display device comprising the optical layered body according to [1] or the layered member according to [2] on the observer side of a display element.

The optical laminate of the present invention is excellent in antiglare properties and scratch resistance, and when applied to a display device, is excellent in image sharpness from near the distance of clear vision, so it is particularly used as the outermost surface of a touch panel display device. It is suitable as an antiglare member.

It is a cross-sectional schematic diagram which shows an example of the optical laminated body of this invention.

[Optical laminate]
The optical layered body of the present invention is an optical layered body having a resin layer containing a binder resin and organic particles on at least one surface of a transparent substrate. The resin layer has an uneven shape on its upper surface, the organic particles are not exposed on the upper surface of the resin layer, and the thickness of the binder resin present on the upper surface side of the organic particles in the resin layer is 0.5 μm or more, and the number of the organic particles contained in the range of 0.1 mm × 0.1 mm when the resin layer is observed from the top is 20 or more, and in accordance with JIS K7374: 2007 It is characterized by a transmission image definition of 20.0 to 55.0% when the width of the optical comb is 2.0 mm. Here, the "upper surface of the resin layer" means the surface of the resin layer opposite to the interface with the transparent substrate.

FIG. 1 is a schematic cross-sectional view showing an example of the optical laminate of the present invention. An optical layered body 100 of the present invention shown in FIG. 1 has a resin layer 2 on one surface of a transparent substrate 1, and the resin layer 2 contains a binder resin 3 and organic particles 4. As shown in FIG. The resin layer 2 has an uneven shape on its upper surface 2a. The uneven shape is preferably a shape following the organic particles 4 contained in the resin layer 2 .
The organic particles 4 are not exposed on the upper surface 2a of the resin layer. That is, in the resin layer 2, the upper surface 2a of the resin layer is covered with the binder resin 3, and the organic particles 4 are present closer to the transparent substrate 1 than the upper surface 2a of the resin layer. In addition, the thickness of the binder resin existing on the upper surface side of the organic particles 4 in the resin layer 2 is represented by t in FIG. 1, and t is 0.5 μm or more.

Since the optical layered body of the present invention has the above structure, it is excellent in antiglare property and scratch resistance, and when applied to a display device, is excellent in image sharpness when viewed from near the distance of clear vision.
Conventionally, in the field of antiglare films, the scratch resistance of the film surface has been evaluated on the basis of surface hardness. However, since the anti-glare film constituting the outermost surface of the touch panel is used by contacting the surface with a finger or a touch pen, it is sufficient to improve the surface hardness of the film (for example, pencil hardness of the surface). found to be ineffective. Furthermore, the present inventors have found that the results of the surface hardness of the film and the evaluation of whether or not the film surface is likely to be scratched when a force is applied in the horizontal direction do not always match. . For example, in order to achieve both antiglare property and pencil hardness in an antiglare film, a method of providing a clear hard coat layer between a transparent substrate and an antiglare layer is known (for example, International Publication No. 2008/020613 ). When the clear hard coat layer is positioned inside (on the side of the transparent base material) the antiglare layer, the antiglare property of the antiglare film is not hindered by the clear hard coat layer, and thus good antiglare properties are obtained. can demonstrate their sexuality. Further, since the pencil hardness is influenced not only by the hardness of the surface but also by the hardness of the base, the pencil hardness can be improved by forming the antiglare film as described above. However, even if the antiglare film has the above structure, it does not affect the durability when the film surface is rubbed by applying force in the horizontal direction. Therefore, although the pencil hardness can be improved, the steel wool resistance is improved. I couldn't let it go.
Therefore, the present inventors have made intensive studies to not only improve the surface hardness of an optical laminate having antiglare properties, but also to make the surface scratch-resistant even in a steel wool resistance test. This led to the completion of the optical laminate of No.

Further, in general, image sharpness tends to decrease as the antiglare property is improved. Therefore, when priority is given to image clarity when viewed from a distance from the display screen, such as in a TV monitor, the antiglare property must be sacrificed to some extent. On the other hand, since mobile type information terminal equipment equipped with a touch panel is frequently used outdoors, a high level of anti-glare property is essential in order to reduce reflection of external light. In addition, since the touch panel is operated while looking at the display screen at hand, the image clarity when viewing the display screen from a long distance is not required, and the image clarity when viewing from near the clear vision distance is optimized. It is important to.
Focusing on the above points, the optical laminate of the present invention simultaneously achieves optimum antiglare properties and image sharpness as an antiglare member that can be used as an alternative to cover glass for touch panels.

The reason why the optical layered body of the present invention exhibits the above effects can be explained as follows.
First, in the optical layered body of the present invention, the resin layer contains a binder resin and organic particles, and the upper surface of the resin layer has an uneven shape, so that good antiglare properties can be imparted. Furthermore, from the viewpoint of antiglare properties, it is preferable that the resin layer has a thickness portion exceeding the average particle diameter of the organic particles and a thickness portion smaller than the average particle diameter of the organic particles. Details of this will be described later.
Further, the organic particles are not exposed on the upper surface of the resin layer, and the number of organic particles included in the range of 0.1 mm × 0.1 mm when the resin layer is observed from the upper surface side is 20 or more. . When the organic particles are exposed on the upper surface of the resin layer, the organic particles not only easily fall off the resin layer, but also become easily scratched particularly in the steel wool resistance test. It is not suitable for use on the top surface of the device. However, if the organic particles are not exposed on the upper surface of the resin layer and are covered with a binder resin, the surface will not be scratched even if the steel wool resistance test is repeated 1500 times or more, and the top surface of the touch panel display device will not be damaged. High scratch resistance that can withstand practical use can be imparted. On the other hand, if the organic particles are embedded in the resin layer, the antiglare property tends to decrease. can be compatible with sexuality.
Furthermore, in the optical layered body of the present invention, the optical layered body of the present invention can be used as the maximum for a display device as long as the transmission image definition when the width of the optical comb is 2.0 mm is in the range of 20.0 to 55.0%. When installed on a surface, the image sharpness is good when the display screen is viewed from the vicinity of the clear vision distance, and the balance between the antiglare property and the scratch resistance is also optimal.

In this specification, the number of organic particles in the optical laminate and the optical properties (total light transmittance, haze, image clarity, etc.) exclude the minimum and maximum values measured at 16 points unless otherwise specified. It means the average value of the measured values at 14 points.
In this specification, the above 16 measurement points are defined by using a margin of 1 cm from the outer edge of the measurement sample, and drawing a line that divides the area inside the margin into 5 equal parts in the vertical and horizontal directions. It is preferable to use the 16 points of intersection as the center of measurement. For example, when the sample to be measured is a rectangle, a region 1 cm from the outer edge of the rectangle is used as a margin, and the region inside the margin is divided vertically and horizontally into five equal halves. , and the average value thereof to calculate the parameter. If the sample to be measured has a shape other than a quadrangle such as a circle, an ellipse, a triangle, or a pentagon, it is preferable to draw a quadrangle inscribed in the shape and measure 16 points on the quadrangle by the above method.

The members constituting the optical layered body of the present invention are described below.
<Transparent substrate>
The transparent substrate used in the optical layered body of the present invention preferably has optical transparency, smoothness, heat resistance, and excellent mechanical strength. Resin materials constituting such transparent substrates include polyester, acrylic, triacetyl cellulose (TAC), cellulose diacetate, cellulose acetate butyrate, polyamide, polyimide, polyethersulfone, polysulfone, polypropylene, and polymethylpentene. , polyvinyl chloride, polyvinyl acetal, polyether ketone, polycarbonate, polyurethane, and amorphous olefin (Cyclo-Olefin-Polymer: COP), or a mixture of multiple resins. The transparent substrate may be a laminate of two or more plastic films.
Among the above, TAC and acrylic are preferable from the viewpoint of light transmittance and optical isotropy. In addition, COP and polyester are suitable because of their excellent weather resistance. Polyimide, polyamideimide, COP, and the like are preferable when it is desired to impart foldability. From the viewpoint of mechanical strength and dimensional stability, stretched, particularly biaxially stretched polyester (polyethylene terephthalate, polyethylene naphthalate) is preferred. In this specification, "acrylic" means acrylic and/or methacrylic.

The thickness of the transparent substrate is preferably 5-300 μm, more preferably 10-200 μm. The thickness is more preferably 10 to 80 μm when emphasis is placed on thinning of the laminate or the display device itself and foldability.
In order to improve adhesiveness, the surface of the transparent base material may be subjected in advance to physical treatment such as corona discharge treatment, oxidation treatment, or the like, as well as to application of a paint called an anchor agent or primer.

<Resin layer>
The resin layer of the optical laminate of the present invention is a layer that contains a binder resin and organic particles and functions as an antiglare layer.
The resin layer has an uneven shape on its upper surface, which can impart good anti-glare properties. The uneven shape is preferably formed so as to follow the shape of the organic particles contained in the resin layer. A resin layer having such an uneven shape can be formed by applying a coating liquid containing a binder resin or its precursor and organic particles onto the transparent substrate. As the coating method, known coating methods such as gravure coating and bar coating can be used. A coating film obtained by applying the coating liquid can be dried and cured as necessary to form a resin layer having an uneven shape.
Here, the "precursor of the binder resin" means, for example, when the binder resin is a cured product of a curable resin composition, the curable resin composition.

The optical layered body of the present invention may have the predetermined resin layer having an uneven top surface on at least one surface of a transparent base material and have light transmittance. The resin layer may be provided on both sides of the transparent base material. is preferably substantially smooth.

The resin layer has 20 or more organic particles in an area of 0.1 mm×0.1 mm when viewed from above. When the organic particles are embedded in the resin layer, the antiglare property tends to decrease. compatible. The number of the organic particles is preferably 25 or more, more preferably 30 or more, from the viewpoint of expressing high antiglare properties, and preferably 50 or less, more preferably 50 or more, from the viewpoint of the balance with image sharpness. The number is preferably 45 or less.
The number of the organic particles in the resin layer can be measured by optical microscope observation, specifically by the method described in Examples.

It is preferable that the resin layer has a structure having an antiglare resin layer and a surface resin layer in order from the transparent substrate side. The antiglare resin layer contains the organic particles, and the surface resin layer does not contain the organic particles. With such a configuration, the entire upper surface of the antiglare resin layer containing the organic particles can be covered with the surface resin layer, so that the organic particles can be prevented from being exposed on the upper surface of the resin layer. Moreover, since the thickness of the binder resin constituting the upper surface of the resin layer can be easily adjusted, it is also preferable from the viewpoint of easily adjusting the balance between the antiglare property and the scratch resistance. Furthermore, when the resin layer has a structure having an antiglare resin layer and a surface resin layer, the organic particles present in the resin layer can be arranged on the transparent substrate side, so that the uneven shape formed is random. It is possible to improve the in-plane uniformity of the optical properties of the resin layer.
The binder resin contained in the antiglare resin layer and the binder resin contained in the surface resin layer may be the same or different. , preferably contain the same binder resin. In the present invention, "containing the same type of binder resin" means that the binder resin constituting the antiglare resin layer and the binder resin constituting the surface resin layer overlap in whole or in part. From the viewpoint of reducing the interface reflection, the difference in refractive index between the binder resin constituting the antiglare resin layer and the binder resin constituting the surface resin layer is preferably small. Preferably.

The antiglare resin layer preferably contains the binder resin and organic particles, and further contains inorganic fine particles, which will be described later. On the other hand, the surface resin layer preferably contains the binder resin and a fluorine-containing compound described later, and preferably does not contain any particles. Since the surface resin layer does not contain particles, the scratch resistance is further improved. In addition, since the surface resin layer does not contain the inorganic fine particles, fine irregularities derived from the fine particles are not formed, so that the image definition at a distance of clear vision is improved.

(binder resin)
From the viewpoint of mechanical strength, the binder resin contained in the resin layer is preferably a cured product of a curable resin composition.
The curable resin composition may be a thermosetting resin composition or an ionizing radiation curable resin composition, and the ionizing radiation curable resin composition is preferable from the viewpoint of improving the mechanical strength. That is, the binder resin contained in the resin layer is more preferably a cured product of an ionizing radiation-curable resin composition.

A thermosetting resin composition is a composition containing at least a thermosetting resin, and is a resin composition that is cured by heating.
Thermosetting resins include acrylic resins, urethane resins, phenol resins, urea melamine resins, epoxy resins, unsaturated polyester resins, silicone resins, and the like. If necessary, a curing agent is added to these curable resins in the thermosetting resin composition.

The ionizing radiation-curable resin composition is a composition containing a compound having an ionizing radiation-curable functional group (hereinafter also referred to as an "ionizing radiation-curable compound"). Examples of ionizing radiation-curable functional groups include ethylenically unsaturated bond groups such as (meth)acryloyl groups, vinyl groups, and allyl groups, epoxy groups, and oxetanyl groups. As the ionizing radiation-curable compound, a compound having an ethylenically unsaturated bond group is preferable, and a compound having two or more ethylenically unsaturated bond groups is more preferable. Polyfunctional (meth)acrylate compounds are more preferred. Both monomers and oligomers can be used as polyfunctional (meth)acrylate compounds.
In addition, in this specification, "(meth)acrylate" refers to methacrylate and acrylate.
In the present specification, the term "ionizing radiation" refers to electromagnetic waves or charged particle beams that have energy quanta capable of polymerizing or cross-linking molecules, and usually ultraviolet (UV) or electron beam (EB) is used. However, it is also possible to use electromagnetic waves such as X-rays and γ-rays, and charged particle beams such as α-rays and ion beams.

Among polyfunctional (meth)acrylate compounds, bifunctional (meth)acrylate monomers include ethylene glycol di(meth)acrylate, propylene glycol di(meth)acrylate, polyalkylene glycol di(meth)acrylate, 1, 6-hexanediol di(meth)acrylate, 1,9-nonanediol di(meth)acrylate, bisphenol A tetraethoxy di(meth)acrylate, bisphenol A tetrapropoxy di(meth)acrylate, isocyanuric acid di(meth)acrylate, etc. is mentioned.
Tri- or higher functional (meth)acrylate monomers include, for example, trimethylolpropane tri(meth)acrylate, pentaerythritol tri(meth)acrylate, ditrimethylolpropane tetra(meth)acrylate, pentaerythritol tetra(meth)acrylate (PETTA ), dipentaerythritol hexa(meth)acrylate, dipentaerythritol tetra(meth)acrylate, isocyanuric acid-modified tri(meth)acrylate, and the like.
Further, the (meth)acrylate-based monomer may have a partially modified molecular skeleton, and may be modified with ethylene oxide, propylene oxide, caprolactone, isocyanuric acid, alkyl, cyclic alkyl, aromatic, bisphenol, or the like. can also be used.

Examples of polyfunctional (meth)acrylate oligomers include acrylate polymers such as urethane (meth)acrylate, epoxy (meth)acrylate, polyester (meth)acrylate, and polyether (meth)acrylate.
Urethane (meth)acrylates are obtained, for example, by reacting polyhydric alcohols and organic diisocyanates with hydroxy (meth)acrylates.
Preferred epoxy (meth)acrylates are (meth)acrylates obtained by reacting tri- or more functional aromatic epoxy resins, alicyclic epoxy resins, aliphatic epoxy resins, etc. with (meth)acrylic acid, bifunctional (Meth)acrylates obtained by reacting the above aromatic epoxy resins, alicyclic epoxy resins, aliphatic epoxy resins, etc. with polybasic acid and (meth)acrylic acid, and bifunctional or higher aromatic epoxy resins, It is a (meth)acrylate obtained by reacting an alicyclic epoxy resin, an aliphatic epoxy resin, or the like with a phenol and (meth)acrylic acid.

In addition, as ionizing radiation curable compounds having only one ethylenically unsaturated bond group, ethyl (meth) acrylate, butyl (meth) acrylate, hexyl (meth) acrylate, ethylhexyl (meth) acrylate, polyalkylene glycol (meth) Acrylates, styrene, methylstyrene, N-vinylpyrrolidone, and the like can also be used.

The ionizing radiation-curable compounds may be used singly or in combination of two or more.
When a mono- to tri-functional meth (acrylate) monomer is used as the ionizing radiation-curable compound, the ionizing radiation-curable resin composition further contains a tetra- or higher functional meta (acrylate) monomer in order to improve the mechanical strength of the resin layer. It preferably contains acrylate) monomers and/or oligomers, and more preferably contains tetra- to hexa-functional meth(acrylate) monomers and/or oligomers. In this case, the content of the mono- to tri-functional meth(acrylate) monomer in the ionizing radiation-curable compound is preferably 0-60% by mass, more preferably 0-30% by mass.
The content of the ionizing radiation-curable compound in the ionizing radiation-curable resin composition that constitutes the binder resin is preferably 50 to 100% by mass of the total solid content of the ionizing radiation-curable resin composition, and is preferably 75 to 100% by mass. It is more preferably 100% by mass.

When the ionizing radiation-curable compound is an ultraviolet-curable compound, the ionizing radiation-curable resin composition preferably contains additives such as a photopolymerization initiator and a photopolymerization accelerator.
Examples of the photopolymerization initiator include one or more selected from acetophenone, benzophenone, α-hydroxyalkylphenone, Michler's ketone, benzoin, benzyldimethylketal, benzoylbenzoate, α-acyloxime ester, thioxanthone, and the like.
The photopolymerization accelerator can reduce polymerization inhibition by air during curing and increase the curing speed, and is selected from, for example, p-dimethylaminobenzoic acid isoamyl ester, p-dimethylaminobenzoic acid ethyl ester, and the like. One or more types are mentioned.
The photopolymerization initiators and photopolymerization accelerators may be used singly or in combination of two or more.
When the ionizing radiation-curable resin composition contains a photopolymerization initiator or a photopolymerization accelerator, the content thereof should be 1 to 10% by mass relative to the total solid content of the ionizing radiation-curable resin composition. is preferred, and 2 to 8% by mass is more preferred.

(organic particles)
The organic particles are used to form unevenness on the upper surface of the resin layer and impart antiglare properties. Since organic particles have a small difference in hardness from that of the binder resin, cracks are less likely to occur at the interface between the particles and the binder resin compared to inorganic particles, resulting in good resistance to steel wool. When inorganic particles are used as particles for forming unevenness on the upper surface of the resin layer, even if the pencil hardness is improved, cracks are likely to occur at the interface due to the large difference in hardness from the binder resin, and steel wool resistance is reduced. descend.
When the resin layer has a structure having an antiglare resin layer and a surface resin layer, the organic particles are preferably contained only in the antiglare resin layer among the resin layers and not contained in the surface resin layer. This can impart higher steel wool resistance.
Any organic particles may be used as long as they have optical transparency. Examples of the organic particles include spherical, disk-like, rugby ball-like, and irregular shapes, and hollow particles, porous particles, solid particles, and the like having these shapes. From the viewpoint of improving steel wool resistance, the organic particles are preferably spherical solid particles.
Examples of organic particles include particles made of polymethyl methacrylate, acrylic-styrene copolymer, melamine resin, polycarbonate, polystyrene, polyvinyl chloride, benzoguanamine-melamine-formaldehyde condensate, silicone, fluorine-based resin, and polyester-based resin. mentioned. Among the above organic particles, one or more selected from acrylic-styrene copolymer particles and polystyrene particles are preferable. Since polystyrene particles have a high degree of hydrophobicity, when inorganic fine particles, which will be described later, are used in combination, they are uniformly dispersed in the resin layer without being densely packed with silica fine particles, which is a representative example of the inorganic fine particles. Therefore, it is considered that irregularities formed on the upper surface of the resin layer are less uneven. In addition, since the acrylic-styrene copolymer particles are easy to control the refractive index and degree of hydrophilicity/hydrophobicity, they are favorable in terms of easy control of internal haze and aggregation/dispersion.
The organic particles may be used singly or in combination of two or more.

When two or more kinds of organic particles having different refractive indices are used, the refractive index of the organic particles can be regarded as an average value according to the refractive index of each organic particle and the usage ratio. Therefore, it is preferable from the viewpoint of enabling fine setting of the refractive index by adjusting the mixing ratio of the organic particles.
Therefore, in the present invention, particles having two or more different refractive indices may be used as the organic particles. In this case, the difference in refractive index between the first organic particles and the second organic particles is preferably 0.03 or more and 0.10 or less. If the refractive index difference is 0.03 or more, the degree of freedom in controlling the refractive index increases when the two are mixed. Large organic particles are less likely to cause light diffusion. The refractive index difference is more preferably 0.04 or more and 0.09 or less, and further preferably 0.04 or more and 0.07 or less.

The organic particles used in the present invention preferably have an average particle diameter of 7 μm or more from the viewpoint of forming an uneven shape on the upper surface of the resin layer to impart high antiglare properties. When the average particle diameter of the organic particles is 7 μm or more, high antiglare properties can be imparted even in a configuration in which the upper surface of the resin layer is coated with the binder resin without the organic particles being exposed. It can be compatible with abrasion resistance. From the above viewpoint, the average particle size of the organic particles is more preferably 8 μm or more, further preferably 9 μm or more. From the viewpoint of antiglare properties, the average particle size of the organic particles is preferably 15 μm or less, more preferably 13 μm or less, and even more preferably 11 μm or less.
Further, in the present invention, it is preferable that the particle diameters of the organic particles are uniform. This is because when the particle diameters of the organic particles are uniform, the heights of the irregularities formed following the shape of the organic particles are uniform, so that higher resistance to steel wool can be imparted. From this point of view, preferably 80% or more, more preferably 90% or more of all the organic particles have a particle size within the range of the average particle size ±300 nm.

In the present invention, the average particle size of the organic particles can be calculated by the following operations (1) to (3).
(1) A transmission observation image of the optical laminate of the present invention is taken with an optical microscope. A magnification of 500 to 2000 is preferable.
(2) 10 arbitrary particles are extracted from the observation image, the long diameter and short diameter of each particle are measured, and the particle diameter of each particle is calculated from the average of the long diameter and short diameter. The longest diameter is the longest diameter of each particle on the screen. The minor axis is defined as the distance between two points where a line segment perpendicular to the midpoint of the line segment forming the major axis is drawn and the perpendicular line segment intersects the particle.
(3) Perform the same operation 5 times on different screen observation images of the same sample, and take the value obtained from the number average of the particle diameters for a total of 50 particles as the average particle diameter of the particles.
In addition, the average particle diameter of the inorganic fine particles to be described later can be obtained by first imaging the cross section of the optical layered body of the present invention with a TEM or STEM, and performing the same techniques as in (2) and (3) above after imaging. The average particle size of inorganic fine particles can be calculated. The acceleration voltage of the TEM or STEM is preferably 10 kV to 30 kV, and the magnification is preferably 50,000 to 300,000 times.

The content of the organic particles in the resin layer is 0.1 mm × 0.1 mm when the resin layer is observed from the top, from the viewpoint of forming an uneven shape on the top surface of the resin layer to impart high antiglare properties. The number of organic particles included in the range may be 20 or more, preferably 25 or more, more preferably 30 or more. From the viewpoint of obtaining high scratch resistance, the number is preferably 100 or less, more preferably 70 or less, even more preferably 50 or less, and even more preferably 45 or less.
In order to make the number of organic particles contained in the range of 0.1 mm × 0.1 mm when the resin layer is observed from above 20 or more, the content of the organic particles in the resin layer is usually It is more than 1.0% by mass, preferably 5.0 to 30% by mass, more preferably 10 to 20% by mass.

More preferably, the resin layer in the present invention further contains inorganic fine particles as necessary. When inorganic fine particles are contained together with the organic particles in the resin layer, aggregation of the organic particles can be suppressed, so that the organic particles are uniformly dispersed in the resin layer, and irregularities formed on the upper surface of the resin layer are less uneven. It is preferable that the inorganic fine particles have an average particle size of nano-order, but a part of the inorganic fine particles may be agglomerated and contained in the state of particles having a particle size of about several μm.
When the resin layer has a structure having an antiglare resin layer and a surface resin layer, it is preferable that the inorganic fine particles are contained only in the antiglare resin layer and not contained in the surface resin layer. Since the antiglare resin layer contains the organic particles, the layer further contains the inorganic fine particles, which has the effect of reducing irregularities formed on the upper surface of the resin layer. On the other hand, the surface resin layer can achieve higher resistance to steel wool when it does not contain inorganic fine particles. In addition, since fine irregularities derived from inorganic fine particles are not formed, the influence of diffusion due to inorganic fine particles is reduced, and image definition at a distance of clear vision is improved.

From the viewpoint of obtaining the above effects, the inorganic fine particles preferably have an average particle size of 1 nm to 3 μm, more preferably 3 nm to 2 μm, even more preferably 5 nm to 2 μm. The average particle size of the inorganic fine particles is determined by the method described above.

Silica, alumina, zirconia, titania, and the like are suitable as the inorganic substance that constitutes the inorganic fine particles. Among these, silica is preferable from the viewpoint of transparency and from the viewpoint of reducing unevenness in unevenness. Examples of methods for producing fine silica particles include dry methods and wet methods, but wet methods are preferred in order to form aggregates capable of imparting high antiglare properties. The wet method is classified into a precipitation method and a gel method, and either method may be used in the present invention. When wet-process silica fine particles are used as the inorganic fine particles, it is preferable to use amorphous silica fine particles in order to suppress excessive agglomeration.
The silica fine particles obtained by the dry method are known as fumed silica (average particle size: 5 nm to 40 nm), and are used to adjust the viscosity of the composition for forming the antiglare resin layer and to reduce the unevenness of the upper surface of the resin layer to be formed. It can be preferably used when controlling the shape. It suffices to provide a mild anti-glare property that blurs the outline of an object, and when emphasis is placed on image clarity and color clarity, the use of dry-process silica fine particles reduces the unevenness of the upper surface of the resin layer. It can be smoothed and the anti-glare property can be adjusted.

The inorganic fine particles may have their surfaces subjected to a hydrophobic treatment. Examples of the hydrophobizing treatment include a chemical treatment method in which a hydrophobic compound is chemically bonded to the surface of the inorganic fine particles, and a physical treatment method in which a hydrophobic compound is permeated into voids without chemical bonding. In general, a chemical treatment method in which a hydrophobic compound is chemically bonded using an active group such as a hydroxyl group or a silanol group on the surface of inorganic fine particles such as silica fine particles is preferably used from the viewpoint of treatment efficiency.
As the hydrophobic compound used for the hydrophobizing treatment, a silane-based material, a siloxane-based material, a silazane-based material, or the like having a hydrophobic group and a functional group highly reactive with the active group is used. Silane-based materials include chlorosilanes having one linear or branched alkyl group, such as methyltrichlorosilane, ethyltrichlorosilane, n-butyltrichlorosilane; diethyldichlorosilane, di-n-butyldichlorosilane, ethyldimethyl Chlorosilanes having two or more linear alkyl groups or branched alkyl groups, such as chlorosilanes, may be mentioned. Examples of siloxane-based materials and silazane-based materials include siloxane compounds and silazane compounds having at least one linear alkyl group or branched alkyl group.

Reactive inorganic fine particles into which reactive groups have been introduced by surface treatment can also be used as the inorganic fine particles. By introducing a reactive group, the hardness of the resin layer can be improved. As the reactive group, a polymerizable functional group is preferably used, preferably an ionizing radiation-curable functional group. Specific examples thereof include ethylenically unsaturated bond groups such as (meth)acryloyl groups, (meth)acryloyloxy groups, vinyl groups and allyl groups.
Examples of reactive inorganic fine particles include inorganic fine particles surface-treated with a silane coupling agent having a reactive group. In order to treat the surface of inorganic fine particles with a silane coupling agent, there are a dry method in which the silane coupling agent is sprayed onto the inorganic fine particles, and a wet method in which the inorganic fine particles are dispersed in a solvent and then the silane coupling agent is added for reaction. is mentioned.

The content of the inorganic fine particles in the resin layer is preferably 0.1 to 10.0% by mass in the resin layer, more preferably 0.2 to 5.0% by mass, and 0.5 to More preferably, it is 2.5% by mass. By setting it as the said range, it becomes easy to form uneven|corrugated shape with few variations. When the resin layer has a structure having an antiglare resin layer and a surface resin layer, the content of the inorganic fine particles in the antiglare resin layer is preferably 0.2 to 15.0% by mass, more preferably 0.4. ~10.0% by mass.
In addition, the ratio of the content of the inorganic fine particles and the organic particles in the resin layer (the content of the inorganic fine particles/the content of the organic particles) is 0.001 to 1.0 in mass ratio from the viewpoint of obtaining high antiglare properties. is preferably 0.01 to 0.8, and even more preferably 0.04 to 0.5.

Preferably, the resin layer further contains a fluorine-containing compound. In the optical layered body of the present invention, the fluorine-containing compound is preferably contained on the side close to the upper surface of the resin layer. preferably contains a fluorine-containing compound. This improves the scratch resistance (particularly steel wool resistance) of the upper surface of the resin layer. Further, when the optical layered body of the present invention is used for the outermost surface of a display device equipped with a touch panel, antifouling properties can be imparted.
It is generally known that it is preferable to improve surface slipperiness in order to improve resistance to steel wool. As an additive for improving surface lubricity, a fluorine-free silicone compound is generally preferably used. The inventors have found that the use of the compound improves the resistance to steel wool. The reason why such an effect is obtained is not clear, but if lipids or the like adhere to the surface of the resin layer, the frictional force when rubbed with steel wool changes or becomes uneven, reducing the resistance to steel wool. It is believed that this phenomenon can be avoided because the compound has high antifouling properties.
As the fluorine-containing compound, a compound known as a fluorine-based leveling agent is suitable. By including a fluorine-based leveling agent in the binder resin, it is possible to improve the resistance to steel wool and the antifouling property of the upper surface of the resin layer, and to form an uneven shape following the shape of the organic particles on the upper surface of the resin layer. be. Among them, from the viewpoint of obtaining the above effect, a fluorosilicone-based leveling agent is more preferable.

Examples of fluorosilicone-based leveling agents include compounds having a perfluoroalkyl group and a siloxane bond in the molecule. compound. The perfluoroalkyl group preferably has 4 to 10 carbon atoms. A perfluoroalkyl group may be linear or branched. Polyether groups include polyethylene oxide chains, polypropylene oxide chains, copolymers thereof, and the like.
Specific examples of such a fluorosilicone-based leveling agent include compounds represented by the following general formula (1).

In general formula (1) above, R is a perfluoroalkyl group having 4 to 10 carbon atoms, and Q is one or more polyether chains selected from the group consisting of polyethylene oxide chains and polypropylene oxide chains. k and m are each independently 0 or 1, and n is an integer of 1-3.

The fluorosilicone leveling agent may have a reactive group. As the reactive group, a polymerizable functional group is preferably used, preferably an ionizing radiation-curable functional group. Specific examples thereof include ethylenically unsaturated bond groups such as (meth)acryloyl groups, (meth)acryloyloxy groups, vinyl groups and allyl groups.
Specific examples of fluorosilicone leveling agents include X-70-090, X-70-091, X-70-092 and X-70-093 manufactured by Shin-Etsu Chemical Co., Ltd., and Megafac R manufactured by DIC. -08, XRB-4 and the like.

The content of the fluorine-containing compound in the resin layer is preferably 0.01 to 1.5% by mass, more preferably 0.05 to 1.0% by mass. When the resin layer has a structure having an antiglare resin layer and a surface resin layer, the content of the fluorine-containing compound in the surface resin layer is preferably within the above range.

From the viewpoint of antiglare properties, the resin layer preferably has a thickness portion exceeding the average particle diameter of the organic particles and a thickness portion smaller than the average particle diameter of the organic particles. The thickness of the thickest portion of the resin layer (convex portion of uneven shape) is preferably 105 to 150%, more preferably 110 to 140%, of the average particle diameter of the organic particles. When the thickness of the thickest portion of the resin layer is within the above range, high antiglare properties can be achieved while imparting resistance to steel wool. The thickness of the thickest portion of the resin layer is preferably 5 to 15 μm, more preferably 7 to 13 μm, from the viewpoint of balance between curl suppression, mechanical strength, hardness and toughness.
The thickness of the resin layer can be calculated, for example, by measuring the thickness at 20 points from a cross-sectional image taken using a scanning transmission electron microscope (STEM) and calculating the average value of the values at 20 points. It is preferable that the STEM has an acceleration voltage of 10 kV to 30 kV and a magnification of 1000 to 7000 times.
Further, in the present invention, the thickness of the binder resin present on the upper surface side of the organic particles in the resin layer is 0.5 μm or more. If the thickness is less than 0.5 μm, the steel wool resistance of the resin layer is lowered. The thickness is more preferably 1.0 μm or more, still more preferably 1.5 μm or more. From the viewpoint of imparting high antiglare properties, the thickness is preferably 3.5 μm or less, more preferably 3.0 μm or less, and even more preferably 2.5 μm or less.
The thickness of the binder resin present on the upper surface side of the organic particles in the resin layer can be calculated by the same method as for the thickness of the resin layer described above.

In the optical laminate of the present invention, an antireflection layer, an antifouling layer, and an antistatic layer are provided on the surface of the transparent substrate on which the resin layer is not laminated, the upper surface of the resin layer, or between the transparent substrate and the resin layer. You may have functional layers, such as.

<Properties of Optical Laminate>
The optical layered body of the present invention has a transmission image definition of 20.0 to 55.0% with an optical comb width of 2.0 mm, measured according to JIS K7374:2007. When the image definition is within this range, the image definition when the display screen is viewed from near the clear vision distance is also good while achieving high antiglare properties. The image definition is preferably 20.0 to 50.0%, more preferably 25.0 to 40.0%, still more preferably 30.0 to 40.0%.
In the optical layered body of the present invention, transmission image clarity when the width of the optical comb is 2.0 mm is important. When the width of the lens is 1.0 mm, the transmission image definition should be about 1.0 to 20.0%.

It is preferable that the resin layer of the optical layered body of the present invention is not scratched by the steel wool resistance test described below.
Steel wool resistance test: Steel wool #0000 is used, and the load is 250 g/cm ² , the moving speed is 100 mm/sec, and the reciprocating distance is 100 mm, and the reciprocation is repeated 1500 times.
As steel wool #0000, "Bonstar B-204" manufactured by Nippon Steel Wool Co., Ltd. can be used.
Since the optical layered body of the present invention has high resistance to steel wool, it has practically sufficient scratch resistance even when used as the outermost surface of a touch panel display device. In the steel wool resistance test, it is more preferable that the steel wool is reciprocated 3,000 times without causing damage.

In the optical layered body of the present invention, the resin layer preferably has a pencil hardness of 3H or more measured at a load of 500 g and a speed of 1.4 mm/sec according to JIS K5600-5-4:1999. When both the steel wool resistance and the pencil hardness are high, the optical layered body of the present invention has more excellent scratch resistance. The pencil hardness is more preferably 4H or higher, still more preferably 5H or higher.

Furthermore, the optical laminate of the present invention preferably has a total light transmittance (JIS K7361-1:1997) and a haze (JIS K7136:2000) within the following ranges.
The total light transmittance is preferably 90.5% or higher, more preferably 90.7% or higher, even more preferably 91.0% or higher.
The haze is preferably 15 to 50%, more preferably 20 to 40%, even more preferably 20 to 30%.

When the optical laminate has one or more of the functional layers, or via an adhesive layer or the like, a cover glass, a film, or another member such as a polarizing element or a display element described later is further added. In the case of lamination, the optical properties of the optical laminate such as transmission image clarity, total light transmittance, haze, etc. may be improved by removing the functional layer, the adhesive layer and members, or removing the functional layer, adhesive layer, etc. The measurement may be performed after performing a pretreatment to make the film thickness of the agent layer as thin as possible.
On the other hand, mechanical properties such as steel wool resistance and pencil hardness of the resin layer in the optical layered body and the number of organic particles in the resin layer can be improved by performing the above pretreatment if the resin layer is laminated on the outermost surface. can be measured directly without In addition, the resin layer preferably has the aforementioned steel wool resistance and pencil hardness, and high mechanical strength. Therefore, even if another member is further laminated on the upper surface side of the resin layer, the mechanical properties of the resin layer and the number of organic particles in the resin layer are usually maintained at the state before lamination of the other member. .

<Size, shape, etc.>
The optical layered body of the present invention may be in the form of a sheet cut into a predetermined size, or may be in the form of a roll obtained by winding a long sheet. The size of the sheet is not particularly limited, but the maximum diameter is about 2 to 500 inches. The “maximum diameter” refers to the maximum length obtained by connecting two arbitrary points of the optical layered body. For example, if the optical layered body is rectangular, the diagonal of the area will be the maximum diameter. Moreover, when the optical layered body is circular, the diameter is the maximum diameter.
When the optical laminate is in the form of a roll, the width and length of the long sheet wound into the roll are not particularly limited, but generally the width is 300 to 3000 mm and the length is about 50 to 5000 m. is. The roll-shaped optical layered body can be used by being cut into sheets according to the size of a display device or the like. When cutting, it is preferable to exclude roll ends and the like where physical properties are not stable.
Also, the shape of the leaf is not particularly limited, and may be, for example, a polygon (triangle, quadrangle, pentagon, etc.), a circle, or a random irregular shape. More specifically, when the optical layered body has a rectangular shape, the aspect ratio is not particularly limited as long as there is no problem as a display screen. For example, height:width = 1:1, 3:4, 10:16, 9:16, 1:2, etc., but in in-vehicle applications and digital signage with rich design, this aspect ratio is limited. not.

[Method for producing an optical laminate]
The method for producing the optical layered body of the present invention is not particularly limited. A method of forming a resin layer having an uneven shape on its upper surface by curing may be used.
In the method for producing an optical laminate of the present invention, an antiglare resin layer is formed on a transparent substrate using a coating liquid containing a binder resin or its precursor and organic particles, and then a coating solution is formed on the antiglare resin layer. It is preferable to have a step of forming a surface resin layer using a coating liquid containing a binder resin or its precursor and not containing the organic particles, and forming the resin layer on the transparent substrate. By this method, a resin layer having the above-described antiglare resin layer and surface resin layer can be formed on the transparent substrate in order from the transparent substrate side. Since the resin layer has an uneven top surface and the top surface of the resin layer is composed of the surface protective layer, the organic particles are not exposed on the top surface of the resin layer.

As the coating liquid for forming the antiglare resin layer, it is preferable to use a coating liquid containing a binder resin or its precursor and organic particles. As the "precursor of the binder resin", the curable resin composition described above is preferable, and the ionizing radiation curable resin composition is more preferable. Moreover, it is preferable that the coating liquid for forming the antiglare resin layer further contains the aforementioned inorganic fine particles.
The curable resin composition, inorganic fine particles, and preferred aspects thereof are as described above.

The coating liquid for forming the antiglare resin layer may further contain a leveling agent other than the fluorine-containing compound from the viewpoint of forming unevenness conforming to the shape of the organic particles. Examples of leveling agents include silicone-based agents. The content of the leveling agent other than the fluorine-containing compound is preferably 0.01 to 1.5% by mass, more preferably 0.05 to 1.0% by mass, based on the total solid content of the coating liquid for forming the antiglare resin layer. .

Moreover, a solvent is usually used in the coating liquid for forming the antiglare resin layer in order to adjust the viscosity and to dissolve or disperse each component. Since the shape of unevenness after coating and drying may differ depending on the type of solvent, it is preferable to select the solvent in consideration of the saturated vapor pressure of the solvent, the permeability of the solvent to the transparent substrate, and the like.
Specifically, solvents include, for example, ketones (acetone, methyl ethyl ketone (MEK), methyl isobutyl ketone (MIBK), 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 (butanol, cyclohexanol, etc.), cellosolves (methyl cellosolve, ethyl cellosolve, etc.), cellosolve acetates, sulfoxides (dimethyl sulfoxide, etc.), amides (dimethylformamide, dimethylacetamide, etc.), and the like. There may be.

When the transparent base material is an acrylic base material, the solvent tends to swell or dissolve the acrylic base material, so it is preferable to select a solvent that moderately swells or dissolves the acrylic base material.
As such a solvent, alcohols (methanol, ethanol, isopropanol, 1-butanol) are preferable, and among other types of solvents, those with a higher number of carbon atoms tend to be better, and among them, those with a high evaporation rate. tend to be good. For example, ketones include methyl isobutyl ketone, aromatic hydrocarbons include toluene, and glycols include propylene glycol monomethyl ether, and a mixed solvent thereof may be used.
Among the above solvents, those containing one or more selected from methyl isobutyl ketone, isopropanol, 1-butanol, and propylene glycol monomethyl ether are particularly preferred.
Solvents that swell or dissolve the TAC base include MEK, cyclohexanone, MIBK, and the like.

The content of the solvent in the coating liquid for forming the antiglare resin layer is not particularly limited. It is more preferably 220 parts by mass.

As the coating liquid for forming the surface resin layer, it is preferable to use a coating liquid that contains a binder resin or its precursor and does not contain organic particles. It is more preferable to use a coating liquid that does not contain
From the viewpoint of improving scratch resistance, the ionizing radiation-curable resin composition contained in the coating liquid for forming the surface resin layer contains a tetra- or higher functional meth(acrylate) monomer and/or oligomer as an ionizing radiation-curable compound. More preferably, it contains tetra- to hexa-functional meth(acrylate) monomers and/or oligomers. The content of the tetrafunctional or higher meth(acrylate) monomer and/or oligomer in the ionizing radiation-curable compound is preferably 40 to 100% by mass, more preferably 60 to 100% by mass, and still more preferably 90 to 100% by mass. is. Mono- to tri-functional meth (acrylate) monomers may be used as the ionizing radiation-curable compound. In that case, the content of the mono- to tri-functional meth (acrylate) monomer in the ionizing radiation-curable compound is preferably 0 to 60% by mass, more preferably 0 to 30% by mass, still more preferably 0 to 10% by mass.
The coating liquid for forming the surface resin layer preferably further contains a fluorine-containing compound.
Other than the above, the curable resin composition, organic particles, fluorine-containing compound, and preferred aspects thereof are as described above.
The coating liquid for forming the surface resin layer preferably contains a solvent in order to adjust the viscosity and to dissolve or disperse the above components. Examples of the solvent include solvents similar to those exemplified for the coating liquid for forming the antiglare resin layer. The content of the solvent in the coating liquid for forming the surface resin layer is not particularly limited, but is preferably 50 to 250 parts by mass, more preferably 100 to 200 parts by mass, based on 100 parts by mass of the solid content in the coating liquid for forming the surface resin layer. Part is more preferred.

A coating liquid for forming an antiglare resin layer containing an ionizing radiation-curable resin composition and a coating liquid for forming a surface resin layer containing an ionizing radiation-curable resin composition are used as the method for producing the optical laminate of the present invention. A case will be described as an example.
First, the coating liquid for forming the antiglare resin layer described above is applied onto the transparent substrate. The coating liquid for forming the antiglare resin layer is obtained by, for example, homogeneously mixing the resin composition containing the ionizing radiation curable compound, organic particles, and optionally inorganic fine particles, a solvent, etc. in a predetermined ratio. can be prepared by
As a method for applying the coating liquid for forming the antiglare resin layer, known coating methods such as gravure coating and bar coating can be used. Furthermore, it is dried as necessary to form an uncured resin layer on the transparent substrate.
From the viewpoint of forming uneven shapes with little variation, it is preferable to control the drying conditions when forming the antiglare resin layer. Drying conditions can be controlled by drying temperature and air speed in the dryer. Specifically, the drying temperature is preferably 30 to 120° C., and the drying wind speed is preferably 0.2 to 50 m/s. In order to control the leveling of the antiglare resin layer according to the drying conditions, it is preferable to irradiate the ionizing radiation after drying.

Next, the uncured resin layer is irradiated with ionizing radiation such as electron beams and ultraviolet rays to cure the uncured resin layer, thereby forming an antiglare resin layer. Here, when an electron beam is used as the ionizing radiation, the acceleration voltage can be appropriately selected according to the resin used and the thickness of the layer, but usually the uncured resin layer can be cured at an acceleration voltage of about 70 to 300 kV. preferable.
When ultraviolet rays are used as ionizing radiation, radiation containing ultraviolet rays having a wavelength of 190 to 380 nm is usually emitted. There are no particular restrictions on the ultraviolet light source, and for example, high-pressure mercury lamps, low-pressure mercury lamps, metal halide lamps, carbon arc lamps and the like are used.

A surface resin layer is formed on the antiglare resin layer formed as described above using the coating liquid for forming the surface resin layer. For example, the resin composition containing the ionizing radiation-curable compound, and the optionally used fluorine-containing compound, solvent, and the like are homogeneously mixed in predetermined proportions to prepare a coating solution for forming the surface resin layer. The coating liquid is applied onto the antiglare resin layer so as to have a desired thickness after curing, dried as necessary, and then cured to form a surface resin layer comprising a cured product of the ionizing radiation-curable resin composition. can be formed. The coating method and curing method of the coating liquid are the same as the method of forming the antiglare resin layer described above.

[Laminate member]
The lamination member of the present invention comprises the above-described optical laminate of the present invention and a polarizing element.
The layer structure of the laminated member may be a structure in which the optical laminate is laminated on at least one surface of a polarizing element. Specifically, the optical laminate of the present invention is laminated on one surface of the polarizing element and the polarizing element protective film is laminated on the other surface, or the polarizing element protective film is laminated on both sides of the polarizing element. , a structure in which the optical laminate of the present invention is further laminated on one of the polarizing element protective films, and the like. The optical laminate is usually laminated so that the transparent substrate side faces the polarizing element side.
The laminated member of the present invention can also be used as a polarizing plate. The laminated member may further have other optical members such as a retardation film in addition to the polarizing element.

The lamination member of the present invention may be formed by cutting the optical laminate of the present invention and the polarizing element into individual sheets according to the size of the display device, and then laminating the members together. You can match. When the roll-shaped members are pasted together, they may be cut according to the size of the display device after that.
In addition, when the laminated member of the present invention is applied to a display device such as a liquid crystal display device, after bonding the laminated member in the form of a sheet or a roll with a display element or the like described later, it is adjusted to the size of the display device. You can cut it by hand. When cutting, it is preferable to exclude roll ends and the like where physical properties are not stable.

The optical layered body and the layered member of the present invention are used as constituent members of a display device such as a liquid crystal display device, and are arranged so that the upper surface of the resin layer in the optical layered body faces the viewer side (the light emitting surface side of the display device). It is preferable to use Furthermore, the optical layered body or layered member of the present invention is placed on the outermost surface of the display device, and the upper surface of the resin layer in the optical layered body is arranged so as to face the viewer side (the light emitting surface side of the display device). It is preferable to use

[Display device]
A display device of the present invention is characterized by comprising the above-described optical layered body or layered member. From the viewpoint of obtaining the effect of the present invention more effectively, the display device preferably includes the above-described optical layered body or layered member on the viewer side of the display element (the light emitting surface side of the display device). More specifically, the above-described optical layered body or layered member is provided on the outermost surface of the display element on the viewer side, and the upper surface (the surface having the uneven shape) of the resin layer in the optical layered body is on the viewer side. It is preferable that the display device is arranged in such a manner.
The size of the display device is not particularly limited, but the maximum diameter is about 2 to 500 inches. The “maximum diameter” is defined as the maximum length when two arbitrary points of the display device are connected. For example, if the display device is rectangular, the diagonal of the area will be the maximum diameter, and if it is circular, the diameter will be the maximum diameter.

A liquid crystal display element, a plasma display element, an organic EL display element, and the like can be cited as display elements constituting the display device.
A specific configuration of the display element is not particularly limited. For example, in the case of a liquid crystal display element, it consists of a basic structure having, in order, a lower glass substrate, a lower transparent electrode, a liquid crystal layer, an upper transparent electrode, a color filter and an upper glass substrate. The upper transparent electrode is densely patterned.

The display device of the present invention is preferably a display device equipped with a touch panel. A display device equipped with a touch panel has a touch panel on a display element, and a display device equipped with the optical laminate or laminated member of the present invention as a member constituting the touch panel, preferably as a member constituting the outermost surface of the touch panel. mentioned. Also in this embodiment, it is preferable that the upper surface (the surface having the irregular shape) of the resin layer in the optical layered body is arranged so as to face the observer.

Examples of touch panels include capacitive touch panels, resistive touch panels, optical touch panels, ultrasonic touch panels, and electromagnetic induction touch panels.
A resistive touch panel has a basic configuration in which a pair of upper and lower transparent substrates having conductive films are arranged with spacers between the conductive films so that the conductive films face each other, and a circuit is connected to the basic configuration. be.
Capacitive touch panels include a surface type, a projection type, and the like, and the projection type is often used. A projected capacitive touch panel has a basic configuration in which an X-axis electrode and a Y-axis electrode orthogonal to the X-axis electrode are arranged with an insulator interposed therebetween, and a circuit is connected to the basic configuration. More specifically, the basic configuration is as follows: (1) A mode in which the X-axis electrode and the Y-axis electrode are formed on separate surfaces on one transparent substrate, (2) The X-axis electrode and the insulator on the transparent substrate A mode in which a layer and a Y-axis electrode are formed in this order; (3) a mode in which an X-axis electrode is formed on a transparent substrate, a Y-axis electrode is formed on another transparent substrate, and laminated via an adhesive layer or the like. etc. Moreover, the aspect which laminates|stacks another transparent substrate is mentioned to these basic aspects.

EXAMPLES Next, the present invention will be described in more detail with reference to examples, but the present invention is not limited by these examples. "Parts" are based on mass unless otherwise specified.
The atmosphere during each measurement and evaluation in the examples was a temperature of 23° C.±5° C. and a humidity of 40 to 65%. Moreover, before starting each measurement and evaluation, the target sample was exposed to the atmosphere for 30 minutes or more, and then the measurement and evaluation were performed.

1. Measurement and Evaluation of Physical Properties of Optical Laminate Physical properties of the optical laminates of Examples and Comparative Examples were measured and evaluated as follows. Table 1 shows the results. All measurements and evaluations were made on a wrinkled or unstained portion of the sample, and samples were taken from near the center, which is considered to be a relatively stable coating, rather than from the edge of the manufactured sample.

1-1. Number of organic particles in the resin layer Four sides of the optical laminate cut to 100 mm × 100 mm were measured with a mending tape (manufactured by 3M, trade name "810-3-18") with an optical microscope (manufactured by Keyence Corporation, trade name). It was attached to the stage of "Digital Microscope VHX-5000"). The resin layer was observed from the top side of the resin layer with an optical microscope at a magnification of 1000 times using a transmission method, and the number of particles in a 0.1 mm square area was measured at 16 locations, and 14 locations excluding the minimum and maximum measured values. was taken as the number of organic particles.

1-2. Clarity of transmission image An optical laminate cut to 100 mm × 100 mm is measured using an image clarity measuring instrument (trade name: ICM-1T) manufactured by Suga Test Instruments Co., Ltd., and the width of the optical comb is 2 according to JIS K7374: 2007. Transmission image sharpness of 0.0 mm was measured. The light incident surface was on the side of the transparent substrate.

1-3. Antiglare property A black acrylic plate (manufactured by Kuraray Co., Ltd.) was placed on the transparent substrate side of an optical laminate cut to 100 mm × 100 mm via a transparent adhesive (manufactured by Hitachi Chemical Co., Ltd., trade name “DA-1000”). , trade name “Comoglass 502K”) was placed on a horizontal surface, and a fluorescent lamp was placed 2 m above the evaluation sample. Visual observation was made from various angles under an environment in which a fluorescent lamp was moved over the evaluation sample and the illuminance on the evaluation sample was 800 to 1200 Lx, and evaluation was made according to the following criteria.
AA: White reflection is observed on the entire surface of the sample, and clear contrast cannot be recognized.
A: The reflection region of the fluorescent lamp can be recognized as a bright portion, but the shape cannot be recognized as a fluorescent lamp.
B: The boundary between the vicinity of the center of the reflection area of the fluorescent lamp (the portion corresponding to the core of the fluorescent lamp) and its periphery is blurred and cannot be recognized. Furthermore, the boundary between the reflective area and the non-reflective area of the fluorescent lamp is blurred and the boundary cannot be recognized.
C: The boundary between the vicinity of the center of the reflection area of the fluorescent lamp (the portion corresponding to the core of the fluorescent lamp) and its peripheral portion can be clearly recognized. Alternatively, the boundary between the reflective area and the non-reflective area of the fluorescent lamp can be clearly recognized.

1-4. Steel Wool Resistance Black tape (manufactured by Yamato, trade name "Yamato vinyl tape No. 200") was attached to the back surface of the optical laminate cut to 50 mm x 150 mm. With the resin layer of the optical layered body facing up, a mending tape (manufactured by 3M, trade name "810-3-18") was attached to the short side of the back surface of the optical layered body, and a wear tester (Tester Sangyo Co., Ltd.) (trade name “AB-301”)). Steel wool #0000 (manufactured by Nippon Steel Wool Co., Ltd., trade name "Bonstar B-204") is set and brought into contact with the upper surface of the resin layer, with a load of 250 g / cm ² , a moving speed of 100 mm / sec, and a reciprocating distance of 100 mm. , 1500 times and 3000 times. The degree of scratches on the upper surface of the resin layer was visually observed by fluorescent light reflection, and the resistance to steel wool was evaluated according to the following criteria.
A: No scratches were observed even after reciprocating 3000 times.
B: No scratches were observed after 1500 reciprocations, but scratches were observed after 3000 reciprocations. C: Scratches were confirmed after 1500 reciprocations.

1-5. Pencil hardness An optical laminate cut to 50 mm × 100 mm was measured for pencil hardness on the upper surface of the resin layer of the optical laminate at a load of 500 g and a speed of 1.4 mm / sec in accordance with JIS K5600-5-4: 1999. The hard coat property of the obtained optical layered body was evaluated.
A pencil hardness tester (manufactured by Toyo Seiki Seisakusho Co., Ltd.) was used for the measurement. A mending tape (manufactured by 3M, trade name “810-3-18”) was attached to both ends of the cut sample, and attached to the base of a pencil hardness tester. The pencil hardness was defined as the hardness of the pencil used when the pencil hardness test was performed 5 times and no appearance abnormality such as scratches was observed 3 times or more. Regarding appearance abnormalities, scratches, dents, etc. were checked, not including discoloration. For example, the pencil hardness of the optical layered body is 2H if the test is performed 5 times using a 2H pencil and no appearance abnormality occurs 3 times.

1-6. Haze The optical laminate cut into 50 mm×100 mm was measured for haze according to JIS K-7136:2000 using a haze meter (HM-150, manufactured by Murakami Color Research Laboratory). The resin layer surface side was used as the light incident surface.

1-7. Image clarity from a distance of clear vision A mending tape (manufactured by 3M, trade name “810-3 -18”), the characters of the newspaper article were displayed on the tablet in the size “standard”, and the readability of the characters was evaluated according to the following criteria.
A: Characters look clear and sentences can be read clearly B: Characters look a little blurry but there is no problem in reading sentences C: Characters look blurry and sentences are difficult to read

1-8. Thickness of the thickest part of the resin layer/thickness of the binder resin present on the organic particles An optical layered body cut into 2 mm × 5 mm is placed in a silicone-based embedding plate, and an epoxy-based resin is poured as the embedding resin to form an optical layer. The whole body was embedded in resin. After curing the embedding resin at 65 ° C. for 12 hours or more, an ultramicrotome (manufactured by Leica Microsystems, trade name “Ultramicrotome EM UC7”) was used to set the delivery thickness to 100 nm, making it ultra thin. Sections were made. The produced ultra-thin section was collected with a mesh (150) with a collodion membrane and used as a sample for observation with a scanning transmission electron microscope (STEM). It is preferable to sputter Pt--Pd for about 20 seconds because an STEM observation image may be difficult to see if conduction is not obtained in this sample. The sputtering time can be adjusted as appropriate, but 10 seconds is too short, and 100 seconds is too long, so that the sputtered metal forms a particle-like foreign matter image, so care must be taken.
The thickness of the thickest portion of the resin layer and the thickness of the binder resin present on the organic particles were measured as follows. First, using a scanning transmission electron microscope (STEM) (manufactured by Hitachi High-Technologies Corporation, product name "S-4800 (TYPE2)"), a cross-sectional photograph of the STEM sample was taken. When taking this cross-sectional photograph, the detector (selection signal) is set to "TE", the acceleration voltage is set to 30 kV, and the emission is set to "10 μA" for STEM observation. The contrast and brightness were adjusted as appropriate so that each layer could be distinguished. A preferable magnification is 10,000 to 100,000 times, more preferable magnification is 10,000 to 50,000 times, and the most preferable magnification is 25,000 to 50,000 times. When taking cross-sectional photographs, the aperture may be set to 3 for the beam monitor diaphragm, the objective lens diaphragm may be set to 3, and the working distance (W.D.) may be set to 8 mm. The thickness of the obtained cross-sectional image was measured at 20 points, and the thickness was calculated from the average value of the values at 20 points.

2. Production Example 1 of Optical Laminate
Coating liquid A for forming an antiglare resin layer having the following formulation was dried and applied to a transparent base material (triacetylcellulose base material (TAC), "TD80UL" manufactured by Fuji Film Co., Ltd., thickness 80 µm, 200 mm x 600 mm). It was applied so that the amount was 5 g/m ² , dried at 70° C. for 30 seconds, and then irradiated with ultraviolet rays in a nitrogen atmosphere (oxygen concentration of 200 ppm or less) so that the accumulated light amount was 70 mJ/cm ² . An antiglare resin layer was formed.
Next, on the antiglare resin layer, a coating liquid A for forming a surface resin layer having the following formulation was applied so that the coating amount after drying was 5 g/m ² , dried at 70°C for 30 seconds, and then exposed to ultraviolet rays in a nitrogen atmosphere. (oxygen concentration of 200 ppm or less), irradiation was performed so that the integrated light amount was 100 mJ/cm ² , a surface resin layer was formed, and an optical laminate was obtained. The thickness of the thickest portion of the entire resin layer consisting of the antiglare resin layer and the surface resin layer was 11 μm.
The evaluation was performed using the obtained optical layered body. Table 1 shows the results.

<Anti-glare resin layer forming coating solution A>
- 60 parts of trifunctional acrylate monomer (PETA) - 40 parts of hexafunctional acrylate monomer (DPHA) - 3.5 parts of photoinitiator (manufactured by BASF, Irgacure 184)
- Photopolymerization initiator 0.5 parts (manufactured by BASF, Irgacure 907)
・ Silicone leveling agent 0.025 parts ・ Organic particles A (spherical acrylic-styrene copolymer particles (monodisperse), refractive index n = 1.55, average particle diameter 9 μm) 30 parts ・ Organic particles B (spherical acrylic- Styrene copolymer particles (monodisperse), refractive index n = 1.59, average particle size 9 µm) 15 parts Inorganic fine particles 5 parts (wet method (precipitation method) silica, average particle size 1 µm)
・86 parts of solvent (toluene) ・12 parts of solvent (cyclohexanone) ・2 parts of solvent (MIBK)

<Surface Resin Layer Forming Coating Solution A>
· 6-functional acrylate monomer (DPHA) 100 parts · Photoinitiator 4 parts (manufactured by BASF, Irgacure 184)
・Fluorine silicone leveling agent 0.2 parts ・Solvent (MIBK) 150 parts

Example 2
Antiglare resin layer forming coating solution B was prepared by changing the organic particles A to 20 parts and the organic particles B to 10 parts in the antiglare resin layer forming coating solution A of Example 1, except that this was used. An optical laminate was obtained in the same manner as in Example 1. Table 1 shows the results of the evaluation.
Example 3
An optical laminate was obtained in the same manner as in Example 1, except that the surface resin layer of Example 1 was applied in an amount of 4 g/m ² after drying. Table 1 shows the results of the evaluation.

Comparative example 1
The antiglare resin layer forming coating liquid C was prepared by changing the organic particles A to 3 parts and the organic particles B to 2 parts from the antiglare resin layer forming coating liquid A of Example 1, except that this was used. An optical laminate was obtained in the same manner as in Example 1. Table 1 shows the results of the evaluation.

Comparative example 2
A coating liquid D for forming an antiglare resin layer having the following formulation was applied to the transparent substrate so that the coating amount after drying was 7 g/m ² , dried at 70°C for 30 seconds, and then exposed to ultraviolet rays in a nitrogen atmosphere (oxygen concentration 200 ppm or less), the integrated light amount was 100 mJ/cm ² to form an antiglare resin layer, and an optical laminate was obtained.
<Coating liquid D for forming antiglare resin layer>
- 50 parts of pentaerythritol triacrylate (PETA) - 30 parts of urethane acrylate - 5 parts of photoinitiator (manufactured by BASF, Irgacure 184)
・ Silicone leveling agent 0.025 parts ・ Organic particles C (spherical acrylic-styrene copolymer particles, refractive index n = 1.55, average particle diameter 3.5 μm) 14 parts ・ Inorganic fine particles 60 parts (Nissan Chemical Industries ( Co., Ltd., silica fine particles having a reactive functional group introduced on the surface (dispersion), solvent: toluene, solid content: 60% by mass, average particle diameter 5 nm)
・Solvent (toluene) 135 parts ・Solvent (cyclohexanone) 55 parts

Comparative example 3
A coating liquid A for forming an intermediate resin layer having the following formulation was applied to the transparent substrate so that the coating amount after drying was 20 g/m ² , dried at 70°C for 30 seconds, and then exposed to ultraviolet rays in a nitrogen atmosphere (oxygen concentration 200 ppm). Below), the intermediate resin layer was formed by irradiating so that the integrated amount of light was 70 mJ/cm ² . Thereafter, an antiglare resin layer was formed in the same manner as in Comparative Example 2 to obtain an optical laminate.
<Coating liquid A for forming intermediate resin layer>
6-functional acrylate monomer (DPHA) 100 parts Inorganic fine particles 80 parts (manufactured by Nissan Chemical Industries, Ltd., silica fine particles (dispersion liquid) with reactive functional groups introduced on the surface, solvent: toluene, solid content: 60 mass %, average particle size 5 nm)
- Photopolymerization initiator 5 parts (manufactured by BASF, Irgacure 184)
・Silicone-based leveling agent 0.1 part ・Solvent (toluene) 150 parts

Comparative example 4
Antiglare resin layer forming coating solution E was prepared by changing the amount of organic particles A to 40 parts and the amount of organic particles B to 20 parts in antiglare resin layer forming coating solution A of Example 1, except that this was used. An optical laminate was obtained in the same manner as in Example 1. Table 1 shows the results of the evaluation.

As shown in the results of Table 1, the optical laminate and the display device of the present invention are excellent in antiglare property and scratch resistance, and when applied to the display device, the image sharpness from the vicinity of the clear vision distance is also good. Good.
On the other hand, in the optical layered body of Comparative Example 1, the number of organic particles included in the range of 0.1 mm × 0.1 mm was less than 20, and the transmission image definition was 50 when the width of the optical comb was 2.0 mm. Since it exceeded 0%, the anti-glare property was insufficient. In the optical layered body of Comparative Example 2, the thickness of the binder resin present on the organic particles was thin, and the thickness of the entire resin layer was also thin, so the resistance to steel wool and the pencil hardness were lowered. The optical layered body of Comparative Example 3 had good pencil hardness due to the presence of the intermediate resin layer, but had low resistance to steel wool due to the thin thickness of the binder resin present on the organic particles. Further, in Comparative Example 4, the transmission image definition was less than 20.0% when the width of the optical comb was 2.0 mm, so the image definition from the clear vision distance was insufficient.

The optical laminate of the present invention is excellent in antiglare properties and scratch resistance, and when applied to a display device, is excellent in image sharpness from near the distance of clear vision, so it is particularly used as the outermost surface of a touch panel display device. It is suitable as an antiglare member. In addition, it is also useful as a constituent member of a polarizing plate used in a display device or the like.

REFERENCE SIGNS LIST 100 optical laminate 1 transparent substrate 2 resin layer 2a upper surface of resin layer 3 binder resin 4 organic particles

Claims (13)

An optical laminate having a resin layer containing a binder resin and organic particles on at least one surface of a transparent substrate,
The resin layer has an uneven shape on its upper surface, and has a thickness portion exceeding the average particle diameter of the organic particles and a thickness portion smaller than the average particle diameter of the organic particles,
The organic particles are not exposed on the upper surface of the resin layer, the binder resin present on the upper surface side of the organic particles in the resin layer has a thickness of 0.5 μm or more, and the resin layer is disposed on the upper surface. The number of the organic particles contained in the range of 0.1 mm × 0.1 mm when observed from is 20 or more,
An optical layered body having a transmission image definition of 20.0 to 55.0% with an optical comb width of 2.0 mm, measured according to JIS K7374:2007. 2. The optical laminate according to claim 1, wherein the organic particles have an average particle size of 7 [mu]m or more. 3. The optical laminate according to claim 1, wherein the binder resin is a cured product of an ionizing radiation-curable resin composition. 4. The optical laminate according to any one of claims 1 to 3, wherein the resin layer is not scratched by the following steel wool resistance test.
Steel wool resistance test: Steel wool #0000 is used, and a load of 250 g/cm ² , a moving speed of 100 mm/sec, and a reciprocating distance of 100 mm are reciprocated 1500 times. The pencil hardness of the resin layer measured at a load of 500 g and a speed of 1.4 mm / sec in accordance with JIS K5600-5-4: 1999 is 4H or more, according to any one of claims 1 to 4. Optical laminate. The optical laminate according to any one of claims 1 to 5, wherein the resin layer contains a fluorine-containing compound. The resin layer has an antiglare resin layer and a surface resin layer in order from the transparent substrate side, the antiglare resin layer contains the organic particles, and the surface resin layer does not contain the organic particles. The optical laminate according to any one of claims 1 to 6. The optical laminate according to claim 7, wherein the antiglare resin layer contains inorganic particles and the surface resin layer does not contain inorganic particles. The optical laminate according to any one of claims 1 to 8, which has a haze of 15 to 50% as measured according to JIS K7136:2000. A laminate member comprising the optical laminate according to any one of claims 1 to 9 and a polarizing element. An antiglare resin layer is formed on the transparent substrate using a coating liquid containing the binder resin or its precursor and the organic particles, and then the binder resin or its precursor is applied on the antiglare resin layer. 10. The method according to any one of claims 1 to 9 , further comprising a step of forming a surface resin layer using a coating liquid containing no organic particles, and forming the resin layer on the transparent base material. and a method for manufacturing an optical laminate. A display device comprising the optical layered body according to any one of claims 1 to 9 or the layered member according to claim 10 on the observer side of a display element. 13. The display device according to claim 12 , which is a display device equipped with a touch panel.