JP6739601B1 - Optical laminated body and display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an optical laminated body including a front plate and a touch sensor panel in order, which is excellent in impact resistance and bending resistance. An optical laminate including a front plate and a touch sensor panel, wherein the touch sensor panel includes a transparent conductive layer and a base material layer supporting the transparent conductive layer, and a tensile force of the front plate. When the elastic modulus is a [GPa], the toughness of the base material layer is b [mJ/mm3], and the thickness of the base material layer is c [μm], the evaluation parameter A calculated by the following formula (1) is An optical laminate satisfying the relationship of the following formula (2a). A=a×b/c (1) A≧1.0 (2a) [Selection diagram] FIG.

Description

The present invention relates to an optical laminate and a display device.

Japanese Patent Laying-Open No. 2017-0554140 (Patent Document 1) describes a touch panel laminate used for an optical display device.

JP, 2017-054140, A

The present invention provides an optical laminate including a front plate and a touch sensor panel in order, which is excellent in impact resistance and bending resistance, and a display device including the optical laminate. To aim.

The present invention provides the following optical layered body and display device.
[1] An optical laminate including a front plate and a touch sensor panel,
The touch sensor panel includes a transparent conductive layer and a base material layer supporting the transparent conductive layer,
When the tensile elastic modulus of the front plate is a [GPa], the toughness of the base material layer is b [mJ/mm ³ ], and the thickness of the base material layer is c [μm], it is calculated by the following formula (1). The evaluation parameter A is an optical layered body that satisfies the relationship of the following formula (2a).
A=a×b/c (1)
A≧1.0 (2a)

[2] The optical laminate according to [1], wherein the evaluation parameter B calculated by the following formula (3) satisfies the relationship of the following formula (4a).
B=b×c (3)
B≧200 (4a)

[3] The optical laminate according to [1] or [2], wherein the front plate includes a hard coat layer.

[4] The optical laminate according to any one of [1] to [3], further including a polarizing plate between the front plate and the touch sensor panel.

[5] The optical layered body according to any one of [1] to [4], wherein the tensile elastic modulus a of the front plate is 5 GPa or more.

[6] The optical layered body according to any one of [1] to [5], wherein the base material layer has a toughness b of 5 mJ/mm ³ or more.

[7] The optical layered body according to any one of [1] to [6], wherein the thickness c of the base material layer is 50 μm or less.

[8] A display device including the optical layered body according to any one of [1] to [7].

According to the present invention, it is possible to provide an optical layered body excellent in impact resistance and bending resistance, and a display device including the optical layered body.

It is a schematic sectional drawing which shows an example of the optical laminated body of this invention. It is a schematic sectional drawing which shows the other example of the optical laminated body of this invention.

Hereinafter, embodiments of the present invention will be described with reference to the drawings, but the present invention is not limited to the following embodiments. In all the following drawings, the scales are appropriately adjusted and shown for easy understanding of the respective components, and the scales of the respective components shown in the drawings do not necessarily match the actual scales of the components.

<Optical laminate>
FIG. 1 is a schematic cross-sectional view of an optical layered body according to an embodiment of the present invention. The optical laminate 100 shown in FIG. 1 includes a front plate 10 and a touch sensor panel 30, and a bonding layer 20 between the front plate 10 and the touch sensor panel 30. The touch sensor panel 30 includes a transparent conductive layer 31 and a base material layer 32 that supports the transparent conductive layer 31. The front plate 10 and the transparent conductive layer 31 may each be a single layer or multiple layers. The base material layer 32 is a single layer.

The tensile elastic modulus of the front plate 10 at a temperature of 23° C. is a [GPa], the toughness of the base material layer 32 at a temperature of 23° C. is b [mJ/mm ³ ], and the thickness of the base material layer 32 is c [μm]. Then, the evaluation parameter A calculated by the following formula (1) satisfies the relationship of the following formula (2a).

A=a×b/c (1)
A≧1.0 (2a)
In the optical layered body, when the evaluation parameter A satisfies the relationship of the above formula (2a), impact resistance and flex resistance can be improved. The front plate 10 and the base material layer 32 are selected so as to satisfy the relationship of the above formula (2a). From the viewpoint of further improving impact resistance and flex resistance, the evaluation parameter A preferably satisfies the relationship of the following expression (2b), and more preferably the relationship of the following expression (2c). Further, the evaluation parameter A preferably satisfies the relationship of the following expression (2d), and may be 50 or less.

A≧2.5 (2b)
A≧20.0 (2c)
A≦100 (2d)
The optical laminated body 100 can be bent at least in the direction in which the front plate 10 is placed inside. The term “bendable” means that the front plate 10 can be bent in a direction inward without causing cracks. The inventors of the present invention have found that an optical laminate including a front plate and a touch sensor panel may not have sufficient bending resistance when the optical laminate is arranged on the viewing side of a flexible display device. Obtained. On the other hand, it became clear that impact resistance tends to be insufficient when a flexible material is used to solve this problem. Then, the present invention has been completed by earnestly studying and finding that the bending resistance and the impact resistance can be improved by adjusting the evaluation parameter A for the optical laminate.

In the optical layered body, the evaluation parameter B calculated by the following formula (3) preferably satisfies the relationship of the following formula (4a).
B=b×c (3)
B≧200 (4a)

In the optical layered body, when the evaluation parameter B satisfies the relationship of the above formula (4a), it is possible to suppress the extension of cracks due to bending. The evaluation parameter B preferably satisfies the relationship of the following expression (4b), more preferably the relationship of the following expression (4c), and may be 1000 or more, from the viewpoint of suppressing the extension of cracks due to bending. .. The evaluation parameter B preferably satisfies the relationship of the following expression (4d), and more preferably satisfies the relationship of the following expression (4e).
B≧500 (4b)
B≧700 (4c)
B≦5000 (4d)
B≦4000 (4e)

In the present specification, the tensile elastic modulus a [GPa] and the toughness b [mJ/mm ³ ] are values measured at a normal temperature (temperature 23° C.) by the method described in Examples below.

The planar shape of the optical layered body 100 may be, for example, a rectangular shape, preferably a rectangular shape having long sides and short sides, and more preferably a rectangular shape. When the shape of the laminate 100 in the surface direction is rectangular, the length of the long side may be, for example, 10 mm or more and 1400 mm or less, and preferably 50 mm or more and 600 mm or less. The length of the short side is, for example, 5 mm or more and 800 mm or less, preferably 30 mm or more and 500 mm or less, and more preferably 50 mm or more and 300 mm or less. Each layer constituting the optical layered body 100 may be rounded at the corners, notched at the ends, or perforated.

The thickness of the optical layered body 100 is not particularly limited as it depends on the function required for the optical layered body and the application of the layered body, but is not limited to, for example, 20 μm or more and 1,000 μm or less, preferably 50 μm or more and 500 μm or less.

The optical layered body 100 can be used, for example, in a display device or the like. The display device is not particularly limited, and examples thereof include an organic electroluminescence (organic EL) display device, an inorganic electroluminescence (inorganic EL) display device, a liquid crystal display device, and an electroluminescent display device. The optical laminate 100 is suitable for a flexible display device. A display device including the optical layered body of the present invention has excellent impact resistance and flex resistance.

The optical layered body 100 includes the bonding layer 20 between the front plate 10 and the touch sensor panel 30. The optical layered body 100 is preferably configured so that it can be used as a part of a display device when used in a display device, and the elements that the display device can include may be included without limitation, and for example, a polarizing plate. A partially formed colored layer, a protective film, a retardation film, etc. may be provided.

FIG. 2 shows an optical layered body 200 having a configuration in which a polarizing plate is provided between the front plate 10 and the touch sensor panel 30. The optical laminate 200 shown in FIG. 2 includes the front plate 10, the bonding layer 20, the polarizing plate 40, the bonding layer 20, and the touch sensor panel 30 in this order. The optical layered body 200 shown in FIG. 2 is different from the optical layered body 100 shown in FIG. 1 only in that a polarizing plate 40 is provided and in that two bonding layers 20 are provided. In the optical laminated body, the polarizing plate is not limited to the configuration provided between the front plate 10 and the touch sensor panel 30, and may be provided on the surface of the touch sensor panel 30 opposite to the front plate 10 side. It may have a laminated structure.

[Front plate]
The front plate 10 is not limited in material and thickness as long as it is a plate that can transmit light, and may be composed of only one layer or may be composed of two or more layers. Examples thereof include a resin-made plate-shaped body (for example, a resin plate, a resin sheet, a resin film, etc.), a glass-made plate-shaped body (for example, a glass plate, a glass film, etc.), and the like. The front plate can be a layer forming the outermost surface of the display device.

The thickness of the front plate 10 may be, for example, 30 μm or more and 500 μm or less, preferably 40 μm or more and 200 μm or less, and more preferably 50 μm or more and 100 μm or less. In the present invention, the thickness of each layer can be measured according to the thickness measuring method described in Examples below.

When the front plate 10 is a resin plate, the resin plate is not limited as long as it can transmit light. Examples of the resin forming the resin plate-like body such as a resin film include triacetyl cellulose, acetyl cellulose butyrate, ethylene-vinyl acetate copolymer, propionyl cellulose, butyryl cellulose, acetyl propionyl cellulose, polyester, polystyrene, and the like. Polyamide, polyetherimide, poly(meth)acrylic, polyimide, polyethersulfone, polysulfone, polyethylene, polypropylene, polymethylpentene, polyvinyl chloride, polyvinylidene chloride, polyvinyl alcohol, polyvinyl acetal, polyether ketone, polyether ether ketone Examples of the film include polymers formed of polymers such as polyether sulfone, polymethylmethacrylate, polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polycarbonate and polyamide imide. These polymers can be used alone or in combination of two or more. From the viewpoint of improving strength and transparency, a resin film formed of a polymer such as polyimide, polyamide or polyamide-imide is preferable.

The front plate 10 has a tensile elastic modulus a at a temperature of 23° C. of preferably 5 GPa or more, and more preferably 6 GPa or more, from the viewpoint of easily forming the optical laminate 100 having excellent impact resistance. .. The front plate 10 preferably has a tensile elastic modulus a at a temperature of 23° C. of 20 GPa or less, more preferably 15 GPa or less, from the viewpoint of easily forming the optical laminate 100 having excellent bending resistance. It is more preferably 10 GPa or less.

The front plate 10 is preferably a film in which a hard coat layer is provided on at least one surface of the base film from the viewpoint of obtaining a desired tensile elastic modulus a. As the substrate film, a film made of the above resin can be used. The hard coat layer may be formed on one surface of the base film, or may be formed on both surfaces. By providing the hard coat layer, the resin film having improved hardness and scratch resistance can be obtained. The hard coat layer is, for example, a cured layer of an ultraviolet curable resin. Examples of the ultraviolet curable resin include acrylic resin, silicone resin, polyester resin, urethane resin, amide resin, and epoxy resin. The hard coat layer may contain an additive in order to improve the strength. The additive is not limited and includes inorganic fine particles, organic fine particles, or a mixture thereof.

When the front plate 10 is a glass plate, tempered glass for display is preferably used as the glass plate. The thickness of the glass plate may be, for example, 50 μm or more and 1,000 μm or less. By using the glass plate, the front plate 10 having excellent mechanical strength and surface hardness can be formed.

When the optical laminate 100 is used in a display device, the front plate 10 has not only a function of protecting the front surface (screen) of the display device (function as a window film) but also a touch detected by the touch sensor panel 30. It may also have a function as an operation surface for performing, and may further have a blue light cut function, a viewing angle adjustment function, and the like.

[Touch sensor panel]
If the touch sensor panel 30 is a sensor that can detect the position touched by the front plate 10 and has a transparent conductive layer 31 and a base material layer 32 that supports the transparent conductive layer 31, the detection method is limited. However, a touch sensor panel such as a resistance film type, an electrostatic capacitance type, an optical sensor type, an ultrasonic type, an electromagnetic inductive coupling type, a surface acoustic wave type is exemplified. Among them, the capacitance type touch sensor panel is preferably used in terms of low cost, fast reaction speed, and thinning. The touch sensor panel 30 may include an adhesive layer, a separation layer, a protective layer, or the like between the transparent conductive layer 31 and the base material layer 32 supporting the transparent conductive layer 31. Examples of the adhesive layer include an adhesive layer and a pressure-sensitive adhesive layer. As the base material layer 32 that supports the transparent conductive layer 31, a base material layer 32 having the transparent conductive layer 31 formed by vapor deposition on one surface, a base material layer 32 to which the transparent conductive layer 31 is transferred via an adhesive layer, and the like. Are listed.

An example of a capacitance type touch sensor panel includes a base material layer, a transparent conductive layer for position detection provided on the surface of the base material layer, and a touch position detection circuit. In a display device provided with an optical laminated body having a capacitance type touch sensor panel, when the surface of the front plate 10 is touched, the transparent conductive layer is grounded through the capacitance of the human body at the touched point. To be done. The touch position detection circuit detects the grounding of the transparent conductive layer, and the touched position is detected. By having a plurality of transparent conductive layers separated from each other, it is possible to detect a more detailed position.

The transparent conductive layer may be a transparent conductive layer made of a metal oxide such as ITO, or a metal layer made of a metal such as aluminum, copper, silver, gold, or an alloy thereof.

The separation layer may be a layer formed on a substrate such as glass and for separating the transparent conductive layer formed on the separation layer together with the separation layer from the substrate. The separation layer is preferably an inorganic layer or an organic layer. Examples of the material forming the inorganic layer include silicon oxide. As a material for forming the organic material layer, for example, a (meth)acrylic resin composition, an epoxy resin composition, a polyimide resin composition, or the like can be used.

The protective layer can be provided in contact with the transparent conductive layer to protect the conductive layer. The protective layer includes at least one of an organic insulating film and an inorganic insulating film, and these films can be formed by a spin coating method, a sputtering method, a vapor deposition method, or the like.

The touch sensor panel 30 can be manufactured, for example, as follows. In the first method, first, the base material layer 32 is laminated on the glass substrate via the adhesive layer. The transparent conductive layer 31 patterned by photolithography is formed on the base material layer 32. By applying heat, the glass substrate and the base material layer 32 are separated, and the touch sensor panel 30 including the transparent conductive layer 31 and the base material layer 32 is obtained.

In the second method, first, the separation layer is formed on the glass substrate, and if necessary, the protective layer is formed on the separation layer. A transparent conductive layer 31 patterned by photolithography is formed on the separation layer (or protection layer). A peelable protective film is laminated on the transparent conductive layer 31, and the transparent conductive layer 31 to the separation layer are transferred to separate the glass substrate. A touch having the transparent conductive layer 31, the separation layer, the adhesive layer, and the base material layer 32 in this order by adhering the base material layer 32 and the separation layer via the adhesive layer and peeling off the peelable protective film. The sensor panel 30 is obtained.

As the base material layer of the touch sensor panel, triacetyl cellulose, polyethylene terephthalate, cycloolefin polymer, polyethylene naphthalate, polyolefin, polycycloolefin, polycarbonate, polyether sulfone, polyarylate, polyimide, polyamide, polystyrene, polynorbornene, etc. A resin film may be used. Polyethylene terephthalate is preferably used from the viewpoint of easily forming a base material layer having a desired toughness.

Base layer of the touch sensor panel, the easily form an optical laminate having excellent bending resistance standpoint, it is preferable that toughness b is 5 mJ / mm ³ or more, still be at 10 mJ / mm ³ or more It is most preferably 50 mJ/mm ³ or more. The toughness b of the base material layer of the touch sensor panel is, for example, 200 mJ/mm ³ or less.

The thickness c of the base material layer of the touch sensor panel is preferably 50 μm or less, and more preferably 30 μm or less from the viewpoint of easily forming an optical laminate having excellent bending resistance. The base material layer of the touch sensor panel has a thickness c of, for example, 5 μm or more.

[Polarizer]
Examples of the polarizing plate 40 include a stretched film having a dye having absorption anisotropy adsorbed thereon, or a film containing a film obtained by coating and curing a dye having absorption anisotropy as a polarizer. Examples of the polarizing plate 40 include a film including a retardation layer in addition to the polarizer.

Examples of the dye having absorption anisotropy include dichroic dyes. Specifically, iodine or a dichroic organic dye is used as the dichroic pigment. The dichroic organic dye includes C.I. I. Included are dichroic direct dyes composed of disazo compounds such as DIRECT RED 39, and dichroic direct dyes composed of compounds such as trisazo and tetrakisazo. As a film used as a polarizer and coated with a dye having absorption anisotropy and cured, a composition containing a dichroic dye having liquid crystallinity or a composition containing a dichroic dye and a polymerizable liquid crystal is used. Examples thereof include a film having a layer obtained by coating and curing. A film coated with a dye having absorption anisotropy and cured is preferable because it has no limitation in the bending direction as compared with a stretched film to which a dye having absorption anisotropy is adsorbed.

(1) Polarizing Plate Having Stretched Film as Polarizer A polarizing plate having a stretched film having a dye having absorption anisotropy adsorbed thereon as a polarizer will be described. The stretched film, which is a polarizer and has a dye having absorption anisotropy adsorbed, is usually a step of uniaxially stretching a polyvinyl alcohol-based resin film, by staining the polyvinyl alcohol-based resin film with a dichroic dye, It is manufactured through a step of adsorbing a dichroic dye, a step of treating the polyvinyl alcohol-based resin film on which the dichroic pigment is adsorbed with a boric acid aqueous solution, and a step of washing with water after the treatment with the boric acid aqueous solution. Such a polarizer may be used as it is as a polarizing plate, or one having a transparent protective film laminated on one side or both sides may be used as a polarizing plate. The thickness of the polarizer thus obtained is preferably 2 μm or more and 40 μm or less.

The polyvinyl alcohol-based resin is obtained by saponifying a polyvinyl acetate-based resin. As the polyvinyl acetate-based resin, in addition to polyvinyl acetate which is a homopolymer of vinyl acetate, a copolymer of vinyl acetate and another monomer copolymerizable therewith is used. Examples of the other monomer copolymerizable with vinyl acetate include unsaturated carboxylic acids, olefins, vinyl ethers, unsaturated sulfonic acids, and acrylamides having an ammonium group.

The saponification degree of the polyvinyl alcohol resin is usually 85 mol% or more and 100 mol% or less, and preferably 98 mol% or more. The polyvinyl alcohol-based resin may be modified, and for example, polyvinyl formal or polyvinyl acetal modified with aldehydes can also be used. The polymerization degree of the polyvinyl alcohol-based resin is usually about 1,000 or more and 10,000 or less, preferably 1,500 or more and 5,000 or less.

A film formed from such a polyvinyl alcohol resin is used as a raw film for a polarizing plate. The method for forming a film of the polyvinyl alcohol-based resin is not particularly limited, and the film can be formed by a known method. The film thickness of the polyvinyl alcohol-based raw film can be, for example, about 10 μm or more and 150 μm or less.

The uniaxial stretching of the polyvinyl alcohol-based resin film can be performed before dyeing with the dichroic dye, simultaneously with dyeing, or after dyeing. When the uniaxial stretching is performed after dyeing, the uniaxial stretching may be performed before the boric acid treatment or during the boric acid treatment. It is also possible to carry out uniaxial stretching in these plural stages. In uniaxial stretching, stretching may be uniaxial between rolls having different peripheral speeds, or uniaxial stretching may be performed using a heat roll. The uniaxial stretching may be dry stretching in which stretching is performed in the atmosphere, or wet stretching in which a polyvinyl alcohol-based resin film is swollen with a solvent. The draw ratio is usually about 3 to 8 times.

The thickness of the polarizing plate provided with the stretched film as a polarizer may be, for example, 1 μm or more and 400 μm or less, or may be 5 μm or more and 100 μm or less.

The material of the protective film to be attached to one side or both sides of the polarizer is not particularly limited, but for example, a cyclic polyolefin-based resin film, triacetyl cellulose, a cellulose acetate-based resin made of a resin such as diacetyl cellulose. Films known in the art such as resin film, polyethylene terephthalate, polyethylene naphthalate, polyester resin film made of resin such as polybutylene terephthalate, polycarbonate resin film, (meth)acrylic resin film, polypropylene resin film, etc. Can be mentioned. From the viewpoint of thinning, the thickness of the protective film is usually 300 μm or less, preferably 200 μm or less, more preferably 100 μm or less, and usually 5 μm or more, preferably 20 μm or more. .. The protective film may or may not have a retardation.

(2) Polarizing Plate Having Film Formed from Liquid Crystal Layer as Polarizer A polarizing plate having a film formed from liquid crystal layer as a polarizer will be described. As a film coated with a dye having absorption anisotropy, which is used as a polarizer, a composition containing a dichroic dye having liquid crystallinity or a composition containing a dichroic dye and a liquid crystal compound is used as a base material. Examples thereof include films obtained by applying and curing. The film may be used as a polarizing plate by peeling the base material or together with the base material, or may be used as a polarizing plate with a structure having a protective film on one side or both sides thereof. The protective film may be the same as the polarizing plate including the above-mentioned stretched film as a polarizer.

The film obtained by coating and curing a dye having absorption anisotropy is preferably thin, but if it is too thin, the strength tends to be low and the processability tends to be poor. The thickness of the film is usually 20 μm or less, preferably 5 μm or less, and more preferably 0.5 μm or more and 3 μm or less.

Specific examples of the film obtained by applying the dye having absorption anisotropy include the films described in JP 2013-148883 A and the like.

The thickness of a polarizing plate provided with a film formed of a liquid crystal layer as a polarizer may be, for example, 1 μm or more and 50 μm or less.

(Retardation layer)
The retardation layer can include one layer or two or more retardation layers. The retardation layer may be a positive A plate such as a λ/4 plate or a λ/2 plate, and a positive C plate. The retardation layer may be formed of the resin film exemplified as the material of the protective film described above, or may be formed of a layer in which a polymerizable liquid crystal compound is cured. The retardation layer may further include an alignment film or a base film. The thickness of the retardation layer may be, for example, 1 μm or more and 50 μm or less.

The optical laminated body can prevent reflection of external light by including a circularly polarizing plate as a polarizing plate.

[Laminating layer]
The bonding layer 20 is a layer interposed between the front plate 10 and the touch sensor panel 30, and may be, for example, an adhesive layer or an adhesive layer. The bonding layer 20 is a layer for bonding the front plate 10 and the touch sensor panel 30, a layer for bonding the front plate 10 and the polarizing plate 40, and a layer for bonding the polarizing plate 40 and the touch panel 30. You can The bonding layer 20 has a colored layer provided between the front plate 10 and the touch sensor panel 30, and when provided in contact with the colored layer, the step of the colored layer can be favorably absorbed. It is preferably an adhesive layer. The optical layered body may include one bonding layer 20 or two or more bonding layers 20. When the optical laminate includes a plurality of bonding layers 20, the plurality of bonding layers may be the same or different from each other.

The pressure-sensitive adhesive layer can be composed of a pressure-sensitive adhesive composition containing a resin such as (meth)acrylic, rubber-based, urethane-based, ester-based, silicone-based, or polyvinyl ether-based resin as a main component. Among them, a pressure-sensitive adhesive composition containing a (meth)acrylic resin as a base polymer, which is excellent in transparency, weather resistance, heat resistance, etc., is preferable. The pressure-sensitive adhesive composition may be an active energy ray curable type or a thermosetting type.

Examples of the (meth)acrylic resin (base polymer) used in the pressure-sensitive adhesive composition include butyl (meth)acrylate, ethyl (meth)acrylate, isooctyl (meth)acrylate, and (meth)acrylic acid 2- A polymer or copolymer having one or more kinds of (meth)acrylic acid ester such as ethylhexyl as a monomer is preferably used. It is preferable to copolymerize a polar monomer with the base polymer. As the polar monomer, for example, (meth)acrylic acid, 2-hydroxypropyl (meth)acrylate, hydroxyethyl (meth)acrylate, (meth)acrylamide, N,N-dimethylaminoethyl (meth)acrylate, glycidyl ( Examples thereof include monomers having a carboxyl group, a hydroxyl group, an amide group, an amino group, an epoxy group and the like such as (meth)acrylate.

The pressure-sensitive adhesive composition may contain only the above base polymer, but usually further contains a crosslinking agent. As the cross-linking agent, a metal ion having a valence of 2 or more and forming a carboxylic acid metal salt with a carboxyl group; a polyamine compound forming an amide bond with a carboxyl group; Examples thereof include epoxy compounds and polyols that form an ester bond with a carboxyl group; and polyisocyanate compounds that form an amide bond with a carboxyl group. Of these, polyisocyanate compounds are preferable.

The active energy ray-curable pressure-sensitive adhesive composition has a property of being cured by being irradiated with an active energy ray such as an ultraviolet ray or an electron beam, and has adhesiveness even before irradiation with the active energy ray. It is a pressure-sensitive adhesive composition having a property that it can be brought into close contact with an adherend such as the above, and can be cured by irradiation with an active energy ray to adjust the adhesion. The active energy ray-curable pressure-sensitive adhesive composition is preferably UV-curable. The active energy ray-curable pressure-sensitive adhesive composition further contains an active energy ray-polymerizable compound in addition to the base polymer and the crosslinking agent. Further, if necessary, a photopolymerization initiator, a photosensitizer and the like may be contained.

The pressure-sensitive adhesive composition includes fine particles for imparting light-scattering properties, beads (resin beads, glass beads, etc.), glass fibers, resins other than base polymers, tackifiers, fillers (metal powder and other inorganic powders). Etc.), antioxidants, ultraviolet absorbers, dyes, pigments, colorants, defoamers, corrosion inhibitors, photopolymerization initiators, and other additives.

It can be formed by applying a diluted solution of the pressure-sensitive adhesive composition in an organic solvent onto a substrate and drying. When the active energy ray-curable pressure-sensitive adhesive composition is used, the formed pressure-sensitive adhesive layer can be irradiated with an active energy ray to give a cured product having a desired degree of curing.

The thickness of each bonding layer 20 is not particularly limited and is, for example, 3 μm or more and 100 μm or less, preferably 5 μm or more and 50 μm or less, and may be 20 μm or more.

Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited to these Examples.

Front plates I to IV, a polarizing plate I, touch sensor panels I to VI, and a bonding layer I shown below were prepared.

[Front plate I]
A transparent base film I (polyamideimide film, thickness 50 μm) is coated with a composition for a hard coat layer, and then a solvent is dried and UV-cured to form a front plate I (one side having a hard coat layer formed thereon). The thickness was 60 μm, the elastic modulus was 7 GPa, and the length was 177 mm×width 105 mm).

The composition for the hard coat layer comprises 30 parts by weight of a multifunctional acrylate (MIWON Specialty Chemical, MIRAMER M340), 50 parts by weight of nanosilica sol (average particle size 12 nm, solid content 40%) dispersed in propylene glycol monomethyl ether, ethyl acetate. 17 parts by weight, 2.7 parts by weight of a photopolymerization initiator (Ciba, I184) and 0.3 parts by weight of a fluorine-based additive (Shin-Etsu Chemical Co., Ltd., KY1203) were blended using a stirrer to obtain polypropylene (PP ) A hard coat layer composition was produced by filtering with a material filter.

<Production of Base Film I>
Under a nitrogen atmosphere, in a 1 L separable flask equipped with a stirring blade, 52 g (162.38 mmol) of 2,2′-bis(trifluoromethyl)benzidine (TFMB) and N,N-dimethylacetamide whose water content was adjusted to 100 ppm. 693.8 g of (DMAc) was added, and TFMB was dissolved in DMAc with stirring at room temperature. Next, 28.90 g (65.05 mmol) of 4,4′-(hexafluoroisopropylidene)diphthalic acid dianhydride (6FDA) and 3,3′,4,4′-biphenyltetracarboxylic acid dianhydride were placed in a flask. 9.57 g (32.52 mmol) of (BPDA) was added, and the mixture was stirred at room temperature for 3 hours. Then, 13.21 g (63.10 mmol) of terephthaloyl chloride (TPC) was added to the flask, and the mixture was stirred at room temperature for 1 hour. Then, 4.99 g (63.10 mmol) of pyridine and 21.91 g (214.66 mmol) of acetic anhydride were added to the flask and stirred at room temperature for 30 minutes, then heated to 70° C. using an oil bath, and further 1 After stirring for a time, a reaction solution was obtained.

The obtained reaction liquid was cooled to room temperature, put into a large amount of methanol in a filament shape, the deposited precipitate was taken out, immersed in methanol for 6 hours, and then washed with methanol. Next, the precipitate was dried under reduced pressure at 100° C. to obtain a polyamideimide resin.

DMAc was added to the obtained polyamide-imide resin so that the concentration would be 15% by mass to prepare a polyamide-imide varnish. The obtained polyamide imide varnish was applied onto a smooth surface of a polyester substrate (manufactured by Toyobo Co., Ltd., trade name "A4100") using an applicator so that the thickness of the self-supporting film was 55 μm, and the temperature was 50° C. 30 After drying for 15 minutes at 140° C. for 15 minutes, a free-standing film was obtained. The self-supporting film was fixed to a metal frame and further dried in the atmosphere at 300° C. for 30 minutes to obtain a polyamideimide film having a film thickness of 50 μm. The polyamideimide film thus obtained was used as the base film I.

[Front plate II]
A transparent base film II (polyamideimide film, thickness: 50 μm) is coated with the composition for a hard coat layer, dried with a solvent, and then UV cured to form a front plate II having a hard coat layer on one side ( The thickness was 60 μm, the elastic modulus was 6 GPa, and the length was 177 mm×width 105 mm). As the composition for the hard coat layer, the same composition as that used for producing the front plate I was used.

<Production of Base Film II>
Under a nitrogen atmosphere, in a 1 L separable flask equipped with a stirring blade, 52 g (162.38 mmol) of 2,2′-bis(trifluoromethyl)benzidine (TFMB) and N,N-dimethylacetamide whose water content was adjusted to 500 ppm. 673.93 g of (DMAc) was added, and TFMB was dissolved in DMAc with stirring at room temperature. Next, 28.90 g (65.05 mmol) of 4,4′-(hexafluoroisopropylidene)diphthalic acid dianhydride (6FDA) was added to the flask, and the mixture was stirred at room temperature for 3 hours. Then, 19.81 g (97.57 mmol) of terephthaloyl chloride (TPC) was added to the flask, and the mixture was stirred at room temperature for 1 hour. Next, 7.49 g (94.65 mmol) of pyridine and 14.61 g (143.11 mmol) of acetic anhydride were added to the flask and stirred at room temperature for 30 minutes, then heated to 70° C. using an oil bath, and further 5 After stirring for a time, a reaction solution was obtained.

The obtained reaction liquid was cooled to room temperature, put into a large amount of methanol in a filament shape, the deposited precipitate was taken out, immersed in methanol for 6 hours, and then washed with methanol. Next, the precipitate was dried under reduced pressure at 100° C. to obtain a polyamideimide resin.

DMAc was added to the obtained polyamide-imide resin so that the concentration would be 15% by mass to prepare a polyamide-imide varnish. The obtained polyamide imide varnish was applied onto a smooth surface of a polyester substrate (manufactured by Toyobo Co., Ltd., trade name "A4100") using an applicator so that the thickness of the self-supporting film was 55 μm, and the temperature was 50° C. 30 After drying for 15 minutes at 140° C. for 15 minutes, a free-standing film was obtained. The self-supporting film was fixed to a metal frame and further dried in the atmosphere at 230° C. for 30 minutes to obtain a polyamideimide film having a film thickness of 50 μm. The polyamideimide film thus obtained was used as the base film II.

[Front plate III]
A transparent base film III (polyamideimide film, thickness 50 μm) is coated with the composition for a hard coat layer, dried with a solvent, and UV-cured to form a front plate III having a hard coat layer formed on one side ( The thickness was 60 μm, the elastic modulus was 5 GPa, and the length was 177 mm×width 105 mm). The hard coat layer composition used was the same as that used when the front plate I was manufactured.

<Production of Base Film III>
Under a nitrogen gas atmosphere, in a 1 L separable flask equipped with a stirring blade, 14.67 g (45.8 mmol) of 2,2′-bis(trifluoromethyl)benzidine (TFMB) and N,N having a water content of 200 ppm were prepared. 233.3 g of dimethylacetamide (DMAc) was added and TFMB was dissolved in DMAc with stirring at room temperature. Then, 4.283 g (13.8 mmol) of 4,4′-oxydiphthalic acid dianhydride (OPDA) was added to the flask, and the mixture was stirred at room temperature for 16.5 hours. After that, 1.359 g (4.61 mmol) of 4,4′-oxybis(benzoyl chloride) (OBBC) and 5.609 g (27.6 mmol) of terephthaloyl chloride (TPC) were added to the flask and stirred at room temperature for 1 hour. .. Next, 4.937 g (48.35 mmol) of acetic anhydride and 1.501 g (16.12 mmol) of 4-picoline were added to the flask, and after stirring at room temperature for 30 minutes, the temperature was raised to 70°C using an oil bath, and further. After stirring for 3 hours, a reaction solution was obtained.

After cooling the obtained reaction liquid to room temperature, 360 g of methanol and 170 g of ion-exchanged water were added to obtain a precipitate of polyamideimide. It was immersed in methanol for 12 hours, collected by filtration and washed with methanol. Next, the precipitate was dried under reduced pressure at 100° C. to obtain a polyamideimide resin.

DMAc was added to the obtained polyamide-imide resin so that the concentration would be 15% by mass to prepare a polyamide-imide varnish. The obtained polyamide imide varnish was applied onto a smooth surface of a polyester substrate (manufactured by Toyobo Co., Ltd., trade name "A4100") using an applicator so that the thickness of the self-supporting film was 55 μm, and the temperature was 50° C. 30 After drying for 15 minutes at 140° C. for 15 minutes, a free-standing film was obtained. The self-supporting film was fixed to a metal frame and further dried in the atmosphere at 300° C. for 30 minutes to obtain a polyamideimide film having a film thickness of 50 μm. The polyamideimide film thus obtained was used as the base film III.

[Front plate IV]
A transparent base film IV (polyamideimide film, thickness 50 μm) is coated with the composition for a hard coat layer, and then the solvent is dried and UV-cured to form a front plate IV (where a hard coat layer is formed on one side). The thickness was 60 μm, the elastic modulus was 3 GPa, and the length was 177 mm×width 105 mm). As the composition for the hard coat layer, the same composition as that used for producing the front plate I was used.

<Production of base film IV>
Under a nitrogen atmosphere, in a 1 L separable flask equipped with a stirring blade, 52 g (162.38 mmol) of 2,2′-bis(trifluoromethyl)benzidine (TFMB) and N,N-dimethylacetamide whose water content was adjusted to 500 ppm. 734.10 g of (DMAc) was added, and TFMB was dissolved in DMAc while stirring at room temperature. Next, 28.90 g (65.05 mmol) of 4,4′-(hexafluoroisopropylidene)diphthalic acid dianhydride (6FDA) was added to the flask, and the mixture was stirred at room temperature for 3 hours. Then, 28.80 g (97.57 mmol) of 4,4′-oxybis(benzoyl chloride) (OBBC) was added to the flask and stirred at room temperature for 1 hour. Next, 7.49 g (94.65 mmol) of pyridine and 14.61 g (143.11 mmol) of acetic anhydride were added to the flask and stirred at room temperature for 30 minutes, then heated to 70° C. using an oil bath, and further 5 After stirring for a time, a reaction solution was obtained.

The obtained reaction liquid was cooled to room temperature, put into a large amount of methanol in a filament shape, the deposited precipitate was taken out, immersed in methanol for 6 hours, and then washed with methanol. Next, the precipitate was dried under reduced pressure at 100° C. to obtain a polyamideimide resin.

DMAc was added to the obtained polyamide-imide resin so that the concentration would be 15% by mass to prepare a polyamide-imide varnish. The obtained polyamide imide varnish was applied onto a smooth surface of a polyester substrate (manufactured by Toyobo Co., Ltd., trade name "A4100") using an applicator so that the thickness of the self-supporting film was 55 μm, and the temperature was 50° C. 30 After drying for 15 minutes at 140° C. for 15 minutes, a free-standing film was obtained. The self-supporting film was fixed to a metal frame and further dried in the atmosphere at 300° C. for 30 minutes to obtain a polyamideimide film having a film thickness of 50 μm. The polyamideimide film thus obtained was used as the base film IV.

[Polarizing plate I]
The polarizing plate 1 was produced as follows. First, after forming a photo-alignment film on a substrate, a composition containing a dichroic dye and a polymerizable liquid crystal compound was applied to the substrate, aligned and cured to obtain a polarizer having a thickness of 2 μm. A 25 μm-thick triacetyl cellulose (TAC) film was laminated on the polarizer via an adhesive layer. The base material was peeled off, and an overcoat layer was formed on the exposed surface. The overcoat layer was prepared by applying a resin composition containing polyvinyl alcohol and water and drying at 80° C. for 3 minutes. The thickness of the overcoat layer was 1.0 μm. Further, on the overcoat layer, a retardation film including a layer in which a liquid crystal compound is polymerized and cured via a pressure-sensitive adhesive layer having a thickness of 5 μm (thickness 11 μm, layer structure: layer in which liquid crystal compound is cured and alignment film). A positive C plate (thickness 3 μm) composed of a λ/4 plate (thickness 3 μm)/adhesive layer (thickness 5 μm)/a liquid crystal compound cured layer and an alignment film was attached. In this way, a polarizing plate 1 having a layer structure of "TAC film/adhesive layer/polarizer/overcoat layer/adhesive layer/retardation film" was produced.

[Touch sensor panel I]
A touch panel sensor I having a length of 177 mm and a width of 105 mm in which a transparent conductive layer, a separation layer, an adhesive layer, and a base material layer were laminated in this order was prepared. The transparent conductive layer contained an ITO layer, the separation layer contained a cured layer of an acrylic resin composition, and the total thickness of both layers was 7 μm. The adhesive layer had a thickness of 3 μm. The base material layer was a polyethylene terephthalate film having a thickness of 12 μm, and the toughness was 69 mJ/mm ³ .

[Touch sensor panel II]
A touch panel sensor II having a length of 177 mm and a width of 105 mm, in which a transparent conductive layer, a separation layer, an adhesive layer, and a base material layer were laminated in this order, was prepared. The transparent conductive layer contained an ITO layer, the separation layer contained a cured layer of an acrylic resin composition, and the total thickness of both layers was 7 μm. The adhesive layer had a thickness of 3 μm. The base material layer was a polyethylene terephthalate film having a thickness of 23 μm, and the toughness was 140 mJ/mm ³ .

[Touch sensor panel III]
A touch panel sensor III having a length of 177 mm and a width of 105 mm, in which a transparent conductive layer, a separation layer, an adhesive layer, and a base material layer were laminated in this order, was prepared. The transparent conductive layer contained an ITO layer, the separation layer contained a cured layer of an acrylic resin composition, and the total thickness of both layers was 7 μm. The adhesive layer had a thickness of 3 μm. The base material layer was a triacetyl cellulose film having a thickness of 50 μm, and the toughness was 40 mJ/mm ³ .

[Touch sensor panel IV]
A touch panel sensor IV having a length of 177 mm and a width of 105 mm, in which a transparent conductive layer, a separation layer, an adhesive layer, and a base material layer were laminated in this order, was prepared. The transparent conductive layer contained an ITO layer, the separation layer contained a cured layer of an acrylic resin composition, and the total thickness of both layers was 7 μm. The adhesive layer had a thickness of 3 μm. The base material layer was a 40 μm thick triacetyl cellulose film and had a toughness of 20 mJ/mm ³ .

[Touch sensor panel V]
A touch panel sensor V having a length of 177 mm and a width of 105 mm, in which a transparent conductive layer, a separation layer, an adhesive layer, and a base material layer were laminated in this order, was prepared. The transparent conductive layer contained an ITO layer, the separation layer contained a cured layer of an acrylic resin composition, and the total thickness of both layers was 7 μm. The adhesive layer had a thickness of 3 μm. The base material layer was a 25 μm thick triacetyl cellulose film and had a toughness of 6 mJ/mm ³ .

[Touch sensor panel VI]
A touch panel sensor VI having a length of 177 mm and a width of 105 mm, in which a transparent conductive layer, a separation layer, an adhesive layer, and a base material layer were laminated in this order, was prepared. The transparent conductive layer contained an ITO layer, the separation layer contained a cured layer of an acrylic resin composition, and the total thickness of both layers was 7 μm. The adhesive layer had a thickness of 3 μm. The base material layer was a cycloolefin polymer film having a thickness of 40 μm, and the toughness was 4 mJ/mm ³ .

[Laminating layer I]
(Meth)acrylic adhesive layer, thickness 25 μm, length 177 mm x width 105 mm
<Example 1>
Both the surface of the front plate 1 on the side to be bonded and the surface of the polarizing plate I (TAC film/adhesive layer/polarizer/overcoat layer/adhesive layer/retardation film) and the transparency of the touch sensor panel I Corona treatment was applied to the surface of the conductive layer side. Then, "front plate I/laminating layer I/polarizing plate I (TAC film/adhesive layer/polarizer overcoat layer/adhesive layer/retardation film)/laminating layer I/touch sensor panel I (transparent conductive) Layer/separation layer/adhesive layer/base material layer)", the layers are laminated using a roll bonding machine, and cured in an autoclave, and the optical laminate 200 shown in FIG. An optical layered body of Example 1 having the same configuration as in Example 1 was obtained. An impact resistance test and a bending resistance test were performed on the obtained optical layered body. The results are shown in Table 1. In addition, with respect to the obtained optical layered body, a crack extension rate evaluation test was performed. The results are shown in Table 2.

<Examples 2 to 6, Comparative Examples 1 and 2>
Optical laminates of Examples 2 to 6 and Comparative Examples 1 and 2 were obtained in the same manner as in Example 1 except that the front plate and the touch sensor panel shown in Table 1 were used in Example 1. .. An impact resistance test and a bending resistance test were performed on the obtained optical layered body. The results are shown in Table 1. In addition, with respect to the obtained optical layered body, a crack extension rate evaluation test was performed. The results are shown in Table 2.

<Measuring method of layer thickness>
The thickness of each layer (hereinafter referred to as "test piece") was measured using a contact-type film thickness measuring device ("MS-5C" manufactured by Nikon Corporation). However, the polarizer layer and the alignment film were measured using a laser microscope (“OLS3000” manufactured by Olympus Corporation).

<Measurement method of tensile modulus>
The tensile modulus of the front plate was measured as follows. A rectangular small piece having a long side of 110 mm and a short side of 10 mm was cut out from the front plate using a super cutter. Then, with the upper and lower grips of a tensile tester (manufactured by Shimadzu Corporation Autograph AG-Xplus tester), both ends of the small piece in the long side direction were sandwiched so that the distance between the grips was 5 cm, and the temperature was 23°C. In the environment of a relative humidity of 55%, the small piece was pulled in the long side direction at a pulling speed of 4 mm/min, and the slope of the straight line between 20 and 40 MPa in the obtained stress-strain curve was calculated as the tensile elastic modulus [GPa]. At this time, the thickness value measured as described above was used as the thickness for calculating the stress.

<Toughness measurement method>
The toughness of the base material layer of the touch sensor panel was measured as follows in accordance with JIS K7161. A rectangular small piece having a long side of 110 mm and a short side of 10 mm was cut out from the base material layer of the touch sensor panel using a super cutter. Then, with the upper and lower grips of a tensile tester (manufactured by Shimadzu Corporation Autograph AG-Xplus tester), both ends of the small piece in the long side direction were sandwiched so that the distance between the grips was 5 cm, and the temperature was 23°C. The pieces were pulled in the long side direction at a pulling rate of 4 mm/min in an environment of relative humidity of 55%. The toughness was calculated as the integrated value of the stress-strain curve from the initial stage to the fracture.

<Impact resistance test>
From the optical layered body 200 obtained in each of the examples and comparative examples, a small piece having a rectangular size of 150 mm long side×70 mm short side is cut out using a super cutter, and the touch sensor panel side of the small piece is interposed with an adhesive layer. I stuck it on an acrylic board. Then, in an environment of a temperature of 23° C. and a relative humidity of 55%, with respect to the small piece, place the evaluation pen so that the pen tip is located at a distance of 10 cm from the outermost surface of the front plate of the small piece and the pen tip faces downward. It was held and the evaluation pen was dropped from that position. The position of the pattern of the transparent conductive layer of the touch sensor panel is written on the front plate of the small piece, and the evaluation pen was dropped so that the pen tip was in contact with the position where the transparent conductive layer was arranged. As the evaluation pen, a pen having a weight of 11 g and a pen tip diameter of 0.7 mm was used. The small piece after the evaluation pen was dropped was visually observed and the touch sensor panel function was confirmed, and evaluated according to the following criteria. Table 1 shows the evaluation results.
A: No crack. Maintains touch sensor panel function.
B: There is a crack. Maintains touch sensor panel function.
C: There is a crack. No touch sensor panel function.

<Flex resistance test>
A flexibility test was conducted at a temperature of 25° C. according to the following procedure. The optical layered body obtained in each of the examples and comparative examples was installed in a bending tester (CFT-720C, manufactured by Covotech) in a flat state (not bent) so that the front plate side was the inner side. After bending the optical laminate so that the distance between the front plates facing each other when it was bent was 4.0 mm, a bending operation for returning to the original flat state was performed. When this bending operation was performed once, the number of times of bending was counted as one, and this bending operation was repeated. The number of times of bending when cracks and/or floating of the pressure-sensitive adhesive layer occurred in the region bent by the bending operation was confirmed as the limit number of times of bending and evaluated as follows. Table 1 shows the evaluation results.
A: Even if the number of bends reached 200,000, the limit number of bends was not reached,
B: The number of flexing cycles reached 100,000 or more and 200,000 or less, and the limit number of flexing times was reached.
C: The number of flexing cycles reached 50,000 or more and less than 100,000, and the limit flexing frequency was reached.
D: The limit number of flexing was reached when the number of flexing was less than 50,000.

<Crack extension rate evaluation test>
The rectangular optical laminates of Examples 1 to 6 and Comparative Examples 1 and 2 (length 177 mm×width 105 mm) were subjected to a crack extension rate measurement test at a temperature of 25° C. according to the following procedure. A notch extending from one surface to the other surface of the optical layered body with a length of 1 mm inward from one end on a bending axis in a direction parallel to the lateral direction crossing the longitudinal center (hereinafter, referred to as " Called "artificial crack"). The bending tester (CFT-720C, manufactured by Covotech) was installed with the optical laminates obtained in each of the Examples and Comparative Examples with artificial cracks in a flat state (not bent), and the front plate side was After bending along the bending axis so as to be the inside (bending to a position where the distance between the facing front plates is 4.0 mm), a bending operation for returning to the original flat state was performed. When this bending operation is performed once, it is counted as the number of times of bending, and this bending operation is repeated 1 million times. When the number of bending times is 100,000, 150,000, 500,000, 1 million, The length was measured, and the average extension speed V [mm/1000 times] was calculated based on the extension amount [mm] from the initial 1 mm.

The average extension speed V is calculated based on (L1/100,000 times)×1000 times based on the extension amount L1 [mm] from the initial 1 mm when the number of bending times is 100,000 times. At this time, the speed V2 calculated by (L2/150,000 times)×1000 times based on the initial expansion amount L2 [mm] from 1 mm, and the expansion amount L3 [mm from the initial 1 mm when the number of bending times is 500,000 times (L3/500,000 times)×1000 times based on the speed V3 calculated from 1000 times and the amount of extension L4 [mm] from the initial 1 mm when the number of flexing times is 1 million times (L4/million times)× The average value of the speed V4 calculated by 1000 times was used. Based on the average elongation rate V, the elongation rate of cracks was evaluated as follows.
A: Average extension speed V is 0.1 mm/1000 times or less B: Average extension speed V is more than 0.1 mm/1000 times 0.5 mm/1000 times or less C: Average extension speed V is more than 0.5 mm/1000 times

In each of the optical layered bodies of Examples 1 to 6 and Comparative Examples 1 and 2, the artificial crack was linearly extended with the increase in the number of times of bending. Therefore, it was found that there is a correlation between the number of times of bending and the elongation rate of the artificial crack. In the optical layered body, cracks similar to artificial cracks are likely to occur due to impact such as cutting. From the results shown in Table 2, it was found that in Examples 1 to 5, even if a crack was generated, the crack could be prevented from becoming large.

10 front plate, 20 laminating layer, 30 touch sensor panel, 31 transparent conductive layer, 32 base material layer, 40 polarizing plate, 100, 200 optical laminate.

Claims (8)

An optical laminate including a front plate and a touch sensor panel,
The touch sensor panel includes a transparent conductive layer and a base material layer supporting the transparent conductive layer,
When the tensile elastic modulus of the front plate is a [GPa], the toughness of the base material layer is b [mJ/mm ³ ], and the thickness of the base material layer is c [μm], it is calculated by the following formula (1). The evaluation parameter A is an optical layered body that satisfies the relationship of the following formula (2a).
A=a×b/c (1)
A≧1.0 (2a) The optical laminate according to claim 1, wherein the evaluation parameter B calculated by the following formula (3) satisfies the relationship of the following formula (4a).
B=b×c (3)
B≧200 (4a) The optical laminate according to claim 1, wherein the front plate includes a hard coat layer. The optical laminate according to claim 1, further comprising a polarizing plate between the front plate and the touch sensor panel. The optical laminate according to any one of claims 1 to 4, wherein the tensile elastic modulus a of the front plate is 5 GPa or more. The optical layered body according to any one of claims 1 to 5, wherein the base material layer has a toughness b of 5 mJ/mm ³ or more. The optical layered body according to claim 1, wherein the base layer has a thickness c of 50 μm or less. A display device comprising the optical layered body according to claim 1.

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