TW202104483A - Optical laminate and display device - Google Patents

Abstract

The objective of the invention is to provide an optical laminate that is bendable and comprises a front plate and a back plate layered with an adhesive layer therebetween, and a colored layer formed in a portion of the surface of the front plate or the back plate on the adhesive layer side, wherein entry of air bubbles of 10 [mu]m or greater between the layers has been suppressed. This optical laminate comprises a front plate, an adhesive layer including a first adhesive layer and a second adhesive layer, and a back plate, which have been layered in this order, and a colored layer formed in a portion of either one of the front plate or the back plate on the adhesive layer side thereof, wherein the adhesive layer is disposed in such a manner that the second adhesive layer is on the colored layer side, and layered in such a manner as to cover at least the end portion on the inner side of the colored layer in a planar view of the optical laminate, the first adhesive layer and the second adhesive layer containing a (meth)acrylic resin, and satisfying (1) 0.01 MPa ≤ storage modulus of the first adhesive layer and the second adhesive layer ≤ 0.1 MPa and (2) 0.5 ≤ loss tangent of the second adhesive layer ≤ 0.8.

Description

Optical laminate and display device

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

Patent Document 1 describes the following foldable display device: a display panel, a polarizing member provided on the display panel, and a window provided on the polarizing member are respectively connected by an adhesive member.

Patent Document 2 describes a double-sided pressure-sensitive adhesive sheet having a first pressure-sensitive adhesive layer and a second pressure-sensitive adhesive layer for bonding a display device and an optical member. Patent Document 3 describes an adhesive sheet having a first adhesive layer and a second adhesive layer arranged between the protective panel and the polarizing film. [Prior Technical Literature] [Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open No. 2017-126061 [Patent Document 2] Japanese Patent Laid-Open No. 2016-194085 [Patent Document 3] Japanese Patent No. 4806730

[The problem to be solved by the invention]

The front panel and the back panel are laminated through the adhesive layer, and a colored layer is partially formed on the adhesive layer side of the front panel or the back panel. The flexible optical laminate has the following cases: bubbles with a size of 10 μm or more are mixed between the layers .

The object of the present invention is to provide an optical laminate in which a front panel and a back panel are laminated via an adhesive layer, and a colored layer is partially formed on the adhesive layer side of the front panel or the back panel and can be bent, which suppresses the interlayer Mix bubbles with a size of 10 μm or more. [Technical means to solve the problem]

The present invention provides the laminate and display device shown below. [1] An optical laminate in which a front plate, an adhesive layer, and a back plate are sequentially laminated, and has either one of the adhesive layer side of the front plate or the adhesive layer side of the back plate partially formed Laminated body of colored layers, The adhesive layer includes a first adhesive layer and a second adhesive layer, and is laminated so that the second adhesive layer becomes the colored layer side, The adhesive layer is arranged so as to cover at least the inner end of the colored layer in the plan view of the optical laminate, The first adhesive layer and the second adhesive layer include (meth)acrylic resin, and Meet the following (1) and (2): (1) 0.01 MPa≦The storage modulus of the first adhesive layer and the second adhesive layer≦0.1 MPa; (2) 0.5≦The loss tangent of the second adhesive layer≦0.8. [2] The optical laminate according to [1], wherein the loss tangent of the first adhesive layer is different from the loss tangent of the second adhesive layer. [3] The optical laminate according to [1] or [2], wherein the thickness of the second adhesive layer is greater than the thickness of the colored layer. [4] The optical laminate according to any one of [1] to [3], wherein the total thickness of the first adhesive layer and the second adhesive layer is 25 μm or more and 150 μm or less. [5] A display device comprising the optical laminate according to any one of [1] to [4]. [6] The optical laminate according to any one of [1] to [4], wherein the compressive elastic modulus of the first adhesive layer is 3 MPa or more and 12 MPa or less. [7] The optical laminate according to any one of [1] to [4], wherein the compression elastic modulus of the second adhesive layer is 3 MPa or more and 5 MPa or less. [Effects of Invention]

According to the present invention, there is provided an optical laminate in which a front panel and a back panel are laminated via an adhesive layer, and a colored layer is partially formed on the adhesive layer side of the front panel or the back panel and can be bent, which suppresses mixing between layers Bubbles over 10 μm in size.

Hereinafter, the 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, in order to make each component easy to understand, the scale is adjusted appropriately. The scale of each component shown in the drawing may not be the same as the actual component.

＜Optical laminated body＞ Fig. 1 is a schematic cross-sectional view of an optical laminate according to an embodiment of the present invention. The optical laminate 100 shown in FIG. 1 (hereinafter also referred to as "laminate") 100 has a front panel 10, an adhesive layer 20, and a back panel 30 laminated in this order. The laminate 100 further includes a coloring layer 40 partially formed on the side of the adhesive layer 20 of the back plate 30. The adhesive layer 20 includes a first adhesive layer 21 and a second adhesive layer 22, and is laminated so that the second adhesive layer 22 becomes the colored layer side. The colored layer 40 may also be partially formed on the adhesive layer 20 side of the front panel 10 instead of being partially formed on the adhesive layer 20 side of the back panel 30.

The laminated body 100 can be bent. The so-called bendable means that it can be bent with a radius of curvature of 3 mm. It is preferable that the laminated body 100 does not produce cracks even if the inner surface of the laminated body 100 has a curvature radius of 3 mm and the number of bending times is 10,000 times.

The thickness of the layered body 100 varies depending on the function required of the layered body and the purpose of the layered body, and therefore is not particularly limited. For example, it is 50 μm or more and 1,000 μm or less, preferably 100 μm or more and 500 μm or less.

The shape of the laminated body 100 in plan view may be, for example, a square shape, preferably a square shape having long sides and short sides, and more preferably a rectangular shape. When the shape of the laminated body 100 in the plane direction is rectangular, the length of the long side may be, for example, 10 mm or more and 1400 mm or less, 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, more preferably 50 mm or more and 300 mm or less.

When the top view shape of the laminate 100 is a square shape, the length of each side of the front panel 10 and the back panel 30 may be the same, and it is preferable that the positions of the ends of the front panel 10 and the back panel 30 are at the same position. When the top view of the laminate 100 is a square shape, the position of the end of the adhesive layer 20 may be the same as the position of the end of the front panel 10 or the back panel 30, or may be inside.

The laminated 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 organic electroluminescence (organic EL) display devices, inorganic electroluminescence (inorganic EL) display devices, liquid crystal display devices, electroluminescence display devices, and the like. The display device may have a touch panel function. The laminated body 100 is suitable for a flexible display device.

Previously, a flexible optical laminate in which a colored layer was partially formed on the surface of the adhesive layer side of the front panel or back panel had the following problems: between the colored layer and the adhesive layer, or between the first adhesive layer and the second adhesive layer 2 Bubbles with a length of 10 μm or more are generated between the adhesive layers, between the front panel or the back panel and the adhesive layer (hereinafter, also referred to as specific bubbles). The inventors conducted diligent research on the suppression of air bubbles, and as a result, it was found that a step difference occurs in the thickness direction of the laminate between the area where the colored layer is present and the area where the colored layer is not present, and the adhesive layer formed on the level difference cannot Following the level difference, bubbles are likely to be generated between the adhesive layer and the front panel or back panel before the colored layer is formed, especially in the level difference between the front panel or back panel and the colored layer. Then, focusing on the adhesive layer and conducting further research repeatedly, it was found that the air bubbles can be suppressed without compromising the flexibility by setting the adhesive layer in a two-layer structure, and the layer in contact with the colored layer of the two layers The loss tangent (hereinafter, also referred to as tanδ) is set within a specific range, and each adhesive layer contains acrylic resin and exhibits a specific storage modulus.

Specific bubbles can be observed by observing the transmission image of the laminated body with an optical microscope. More specific air bubbles are generated in a direction parallel to the inner side of the colored layer than in the laminated body. Therefore, the shape of specific bubbles is mostly linear. When the specific bubbles are linear, the length is 10 μm or more, and the width may be, for example, 0.01 μm or more and 5 μm or less. When specific bubbles are generated, they are mostly generated between the colored layer and the adhesive layer, and between the front or back plate and the adhesive layer. In this case, set the inner end of the colored layer as the reference At the time, it mostly occurs at the position with the reference axis as the axis of symmetry.

(Front panel) The front panel 10 is not limited in material and thickness as long as it is a plate-shaped body that allows light to pass through, and may be composed of only one layer, or may include two or more layers. As an example, a plate-shaped body made of resin (for example, a resin plate, a resin sheet, a resin film, etc.), and a plate-shaped body made of glass (for example, a glass plate, a glass film, etc.) are mentioned. The front panel may be the most surface layer constituting the display device.

The thickness of the front panel 10 may be, for example, 30 μm or more and 2,000 μm or less, preferably 50 μm or more and 1,000 μm or less, and more preferably 50 μm or more and 500 μm or less. In the present invention, the thickness of each layer can be measured in accordance with the thickness measurement method described in the below-mentioned examples.

When the front panel 10 is a plate-shaped body made of resin, the plate-shaped body made of resin is not limited as long as it can transmit light. Examples of resins include films formed from the following polymers: triacetyl cellulose, acetyl cellulose butyrate, ethylene-vinyl acetate copolymer, propylene cellulose, butyl cellulose, and acetyl propylene fiber Element, polyester, polystyrene, polyamide, polyetherimide, poly(meth)acrylic acid, polyimide, polyether stubble, poly stubble, polyethylene, polypropylene, polymethylpentene, Polyvinyl chloride, polyvinylidene chloride, polyvinyl alcohol, polyvinyl acetal, polyether ketone, polyether ether ketone, polyether ether, polymethyl methacrylate, polyethylene terephthalate, poly Butylene terephthalate, polyethylene naphthalate, polycarbonate, polyimide, etc. These polymers can be used alone or in combination of two or more kinds. From the viewpoint of improving strength and transparency, a resin film formed of a polymer such as polyimide, polyimide, and polyimide is preferred. The thickness of the resin-made plate-shaped body may be, for example, 30 μm or more and 2,000 μm or less, preferably 50 μm or more and 1,000 μm or less, more preferably 50 μm or more and 500 μm or less, and may also be 100 μm or less.

The front panel 10 may be a film in which a hard coat layer is provided on at least one surface of the base film to further increase the hardness. As the base film, a film containing the above-mentioned resin can be used. The hard coat layer can be formed on one side of the base film or on both sides. By providing a hard coat layer, it can be a resin film with improved hardness and scratch resistance. The hard coat layer is, for example, a cured layer of ultraviolet curable resin. Examples of ultraviolet curable resins include acrylic resins, silicone resins, polyester resins, urethane resins, amide resins, epoxy resins, and the like. In order to increase the strength, the hard coat layer may also contain additives. The additives are not limited, and examples include inorganic fine particles, organic fine particles, or a mixture of these.

When the front panel 10 is a glass plate, the glass plate preferably uses tempered glass for displays. The thickness of the glass plate can be, for example, 10 μm or more and 1,000 μm or less. By using a glass plate, a front panel 10 with excellent mechanical strength and surface hardness can be constructed.

When the laminated body 100 is used in a display device, the front panel 10 can function as a window film in the display device. The front panel 10 may also have a function as a touch sensor, an anti-blue light function, a viewing angle adjustment function, and the like.

(Adhesive layer) The adhesive layer 20 may be a layer between the front panel 10 and the back panel 30 to bond the same.

The adhesive layer 20 includes a first adhesive layer 21 and a second adhesive layer 22. The composition of the adhesive of the first adhesive layer 21 and the second adhesive layer 22 may be different from each other. The adhesive layer 20 may be, for example, a laminate in which the first adhesive layer 21 and the second adhesive layer 22 are laminated, and the first adhesive layer 21 and the second adhesive layer 22 may be laminated in contact with each other. The adhesive layer 20 is laminated on the front plate 10 or the back plate 30 so that the second adhesive layer 22 becomes the colored layer 40 side. The adhesive layer 20 can be laminated so that the second adhesive layer 22 is closer to the colored layer 40 than the first adhesive layer 21, or it can be laminated so as to be in contact with the colored layer 40. In addition, the adhesive layer 20 is laminated so as to cover at least the inner end of the colored layer 40 in the plan view of the optical laminated body 100. The level difference generated by the colored layer 40 is absorbed by the adhesive layer 20 including the first adhesive 21 having a specific storage modulus and the second adhesive layer 22 having a specific elastic modulus and loss tangent, thereby the following tendency exists : The surface of the adhesive layer becomes smooth, and it is easy to suppress the mixing of specific air bubbles. The adhesive layer 20 is laminated in the following manner: in the top view of the optical laminate 100, it is preferable to cover all of the colored layer 40 and the non-colored portion of the front panel 10 or the back panel 30 from the viewpoint of the absorption step. Part of all. In this specification, the so-called top view refers to viewing from the thickness direction of the layer.

(1st adhesive layer) The first adhesive layer 21 may be attached to one of the front panel 10 or the back panel 30 where the colored layer 40 is not formed. The first adhesive layer 21 contains (meth)acrylic resin.

The storage modulus of the first adhesive layer 21 is 0.01 MPa or more and 0.1 MPa or less, preferably 0.02 MPa or more and 0.08 MPa or less. When the storage modulus of the first adhesive layer 21 is 0.01 MPa or more and 0.1 MPa or less, the laminate 100 tends to easily obtain excellent flexibility. In the present invention, the storage modulus can be measured in accordance with the measurement method described in the column of Examples described later. The storage modulus can adopt the value under normal temperature (temperature 23℃).

The storage modulus of the first adhesive layer 21 can be performed by the selection of the material forming the first adhesive layer 21, or the thickness of the first adhesive layer 21, the manufacturing conditions of the first adhesive layer 21, and the combination thereof. For example, when the first adhesive layer 21 contains an active energy ray-curable adhesive composition, the manufacturing conditions of the first adhesive layer 21 are adjusted by UV irradiation. For example, if a monomer having a relatively large molecular weight is used to manufacture the (meth)acrylic resin contained in the adhesive composition 1 described later, the storage modulus of the first adhesive layer 21 tends to increase. Moreover, for example, if the amount of UV irradiation is increased, the storage modulus of the first adhesive layer 21 tends to increase.

The loss tangent of the first adhesive layer 21 is, for example, 0.7 or less, preferably less than 0.5, and more preferably 0.3 or less.

The first adhesive layer 21 may be formed of an adhesive composition containing (meth)acrylic resin as a main component (hereinafter, also referred to as adhesive composition 1). In addition, the term "(meth)acrylic resin" in this specification means at least one selected from the group consisting of acrylic resins and methacrylic resins. Other words with "(methyl)" are also the same. The adhesive composition 1 may also be an active energy ray hardening type or a thermosetting type.

As the (meth)acrylic resin (base polymer) used in the adhesive composition 1, for example, a polymer or copolymer containing one or more of the following (meth)acrylates as monomers is suitably used Compounds, namely: butyl (meth)acrylate, ethyl (meth)acrylate, hexyl (meth)acrylate, octyl (meth)acrylate, lauryl (meth)acrylate, isopropyl (meth)acrylate Octyl ester, isodecyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, iso(meth)acrylate. In the base polymer, it is preferable to copolymerize a polar monomer. Examples of polar monomers include (meth)acrylic acid, 4-hydroxybutyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, hydroxyethyl (meth)acrylate, (meth) ) Acrylic amide, N,N-dimethylaminoethyl (meth)acrylate, glycidyl (meth)acrylate and the like having carboxyl, hydroxyl, amide, amino, epoxy, etc. body.

The adhesive composition 1 may contain only the above-mentioned base polymer, but usually further contains a crosslinking agent. Examples of the crosslinking agent include: a metal ion having a valence of two or more and forming a metal carboxylic acid salt with a carboxyl group; a polyamine compound forming an amide bond with a carboxyl group; a polyepoxy compound or It is a polyol and forms an ester bond with a carboxyl group; it is a polyisocyanate compound and forms an amide bond with a carboxyl group. Among them, polyisocyanate compounds are preferred.

The so-called active energy ray curable adhesive composition is an adhesive composition that has the property of being cured by being irradiated with active energy rays such as ultraviolet rays or electron beams, and has the following properties, that is, before the active energy rays are irradiated It has adhesiveness and can be closely attached to adherends such as films, and can be cured by irradiation of active energy rays to adjust the adhesive force. The active energy ray curable adhesive composition is preferably an ultraviolet curable adhesive composition. The active energy ray curable adhesive composition further contains an active energy ray polymerizable compound in addition to the base polymer and the crosslinking agent. There are also cases where a photopolymerization initiator, photosensitizer, etc. are further contained as needed.

The adhesive composition 1 may contain fine particles, beads (resin beads, glass beads, etc.), glass fibers, resins other than the base polymer, adhesiveness imparting agents, fillers (metal powder or other inorganic Powder, etc.), antioxidants, ultraviolet absorbers, dyes, pigments, colorants, defoamers, corrosion inhibitors, photopolymerization initiators and other additives.

It can be formed by applying the organic solvent diluent of the adhesive composition 1 on the substrate and drying it. In the case of using an active energy ray-curable adhesive composition, by irradiating the formed adhesive layer with active energy rays, a cured product having a desired degree of curing can be obtained.

From the viewpoint of followability and flexibility, the thickness of the first adhesive layer 21 is preferably thinner, for example, preferably 3 μm or more and 100 μm or less, more preferably 5 μm or more and 50 μm or less, or 20 Above μm.

(Second adhesive layer) The second adhesive layer 22 may be bonded to one of the colored layers 40 formed on the front panel 10 or the back panel 30. The second adhesive layer 22 contains (meth)acrylic resin.

The loss tangent of the second adhesive layer 22 is 0.5 or more and 0.8 or less, preferably 0.55 or more and 0.75 or less. When the loss tangent of the second adhesive layer 22 is 0.5 or more and 0.8 or less, there is a tendency to easily obtain excellent followability. In the present invention, the loss tangent can be measured in accordance with the measurement method described in the column of Examples described later. The loss tangent can be the value at room temperature (temperature 23°C).

The loss tangent of the second adhesive layer 22 can be adjusted by a combination of the selection of the material forming the second adhesive layer 22, the thickness of the second adhesive layer 22, the manufacturing conditions of the second adhesive layer 22, and the like. For example, if a monomer having a relatively large molecular weight is used to manufacture the (meth)acrylic resin contained in the adhesive composition 2 described later, the loss tangent of the second adhesive layer 22 tends to increase.

The storage modulus of the second adhesive layer 22 is 0.01 MPa or more and 0.1 MPa or less, preferably 0.02 MPa or more and 0.08 MPa or less. When the storage modulus of the second adhesive layer 22 is 0.01 MPa or more and 0.1 MPa or less, the laminate 100 tends to easily obtain excellent flexibility.

The method of adjusting the storage modulus of the second adhesive layer 22 is the same as the method exemplified in the description of the first adhesive layer 21 described above. The second adhesive layer 22 may be formed of an adhesive composition (hereinafter, also referred to as an adhesive composition 2). The adhesive composition 2 can be formed of an adhesive composition containing the above-mentioned (meth)acrylic resin as a main component. From the viewpoint of loss tangent, the adhesive composition 2 is preferably an active energy ray hardening type.

The (meth)acrylic resin (base polymer), crosslinking agent, photopolymerization initiator, additives, etc. contained in the adhesive composition 2 are the same as those exemplified in the description of the adhesive composition 1, respectively. The method of forming the second adhesive layer can be the same as the method of forming the first adhesive layer.

From the viewpoint of absorbing the level difference of the colored layer 40, the thickness of the second adhesive layer 22 is preferably greater than the thickness of the colored layer 40, for example, preferably 3 μm or more and 100 μm or less, more preferably 5 μm or more and 50 μm Below, it may be 20 μm or more.

(Total thickness of adhesive layer) The total thickness of the first adhesive layer 21 and the second adhesive layer 22 may be, for example, 25 μm or more and 150 μm or less, preferably 30 μm or more and 125 μm or less, and more preferably 40 μm or more and 100 μm or less. When the total thickness is within the above-mentioned range, there is a tendency to easily obtain good step followability and bending resistance.

(Difference of loss tangent) The loss tangent of the first adhesive layer 21 may be different from the loss tangent of the second adhesive layer 22, and is preferably smaller than the loss tangent of the second adhesive layer 22. When the loss tangents of the first adhesive layer 21 and the second adhesive layer 22 are different, the absolute value of the difference can be, for example, 0.05 or more, preferably 0.25 or more and 0.5 or less.

(Compression modulus of elasticity) The compressive elastic modulus of the first adhesive layer may be, for example, 3 MPa or more and 12 MPa or less. When the compressive elastic modulus of the first adhesive layer is 3 MPa or more, the first adhesive layer tends to be difficult to peel off from the adherend during bending. On the other hand, when the compressive elastic modulus of the first adhesive layer is 12 MPa or less, there is a tendency that cracks are not easily generated on the front panel and the back panel during bending. From the viewpoint of the above-mentioned suppression of peeling and cracks, the compressive modulus of elasticity of the first adhesive layer is preferably 3 MPa or more and 10 MPa or less.

The compressive modulus of elasticity of the second adhesive layer may be 3 MPa or more and 5 MPa or less, for example. When the compression modulus of the second adhesive layer is within the above range, the second adhesive layer tends to have excellent step followability.

(Back panel) As the back plate 30, a plate-shaped body that allows light to pass through, a component used in a normal display device, or the like can be used.

The thickness of the back plate 30 may be, for example, 5 μm or more and 2,000 μm or less, preferably 10 μm or more and 1,000 μm or less, and more preferably 15 μm or more and 500 μm or less.

The plate-shaped body used for the back plate 30 may include only one layer or two or more layers, and the plate-shaped body exemplified in the back plate 10 can be used.

As constituent elements used in a normal display device for the back panel 30, for example, a polarizing plate, a touch sensor panel, a retardation film, and the like can be cited.

(Polarizer) Examples of the polarizing plate include a stretched film on which a dye having absorption anisotropy is adsorbed, or a film obtained by coating and curing a dye having absorption anisotropy as a polarizing element. Examples of dyes having absorption anisotropy include dichroic dyes. As the dichroic dye, specifically, iodine or a dichroic organic dye is used. The dichroic organic dyes include C.I. Direct Red 39 and other dichroic direct dyes containing bisazo compounds, and dichroic direct dyes containing compounds such as trisazo and tetrasazo. As a film coated with a pigment having absorption anisotropy used as a polarizing element, there can be mentioned a stretched film adsorbed with a pigment having absorption anisotropy, or a film having the following layers, the layer coating includes liquid crystal It is obtained by hardening a composition of a dichroic dye or a composition containing a dichroic dye and a polymerizable liquid crystal. The film obtained by coating and hardening the pigment with absorbing anisotropy has no limitation on the bending direction, so it is better than the stretched film adsorbed with the pigment with absorbing anisotropy.

(1) Polarizing plate with stretched film as polarizing element A polarizing plate equipped with a stretched film to which a pigment having absorption anisotropy is adsorbed as a polarizing element will be described. As a polarizing element, a stretched film with absorption anisotropy pigment adsorbed is usually manufactured through the following steps, that is, a step of uniaxially stretching a polyvinyl alcohol-based resin film; by using a dichroic pigment to make the polyvinyl alcohol The step of dyeing the resin film and adsorbing the dichroic pigment; and the step of treating the polyvinyl alcohol resin film with the dichroic pigment adsorbed by the boric acid aqueous solution; and washing with water after the treatment with the boric acid aqueous solution. The polarizing element can be used directly as a polarizing plate, or a transparent protective film can be laminated on one or both sides of the polarizing element as a polarizing plate. The thickness of the polarizing element 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 resin, in addition to polyvinyl acetate which is a homopolymer of vinyl acetate, a copolymer of vinyl acetate and other monomers copolymerizable therewith is used. Examples of other monomers copolymerizable with vinyl acetate include unsaturated carboxylic acids, olefins, vinyl ethers, unsaturated sulfonic acids, and acrylamides having an ammonium group.

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

A film formed of such a polyvinyl alcohol-based resin can be used as a blank film of a polarizing plate. The method of forming a polyvinyl alcohol-based resin into a film is not particularly limited, and the film can be formed by a known method. The film thickness of the polyvinyl alcohol-based green 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 the dyeing with the dichroic dye, at the same time as the dyeing, or after the dyeing. In the case of uniaxial stretching after dyeing, the uniaxial stretching may be performed before the boric acid treatment, or may be performed during the boric acid treatment. Moreover, it is also possible to perform uniaxial extension in these plural stages. In the case of uniaxial stretching, it can be uniaxially extended between rollers with different peripheral speeds, or can be extended uniaxially by using hot rollers. In addition, the uniaxial stretching may be dry stretching in the atmosphere, or wet stretching in a state where the polyvinyl alcohol-based resin film is swollen with a solvent. The stretching ratio is usually about 3 to 8 times.

The thickness of the polarizing plate provided with the stretched film as the polarizing element 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 single-sided or double-sided protective film attached to the polarizing element is not particularly limited. Examples include: cyclic polyolefin resin film, including triacetyl cellulose, diacetyl cellulose, and the like Cellulose acetate resin film of resin, polyester resin film including resins such as polyethylene terephthalate, polyethylene naphthalate and polybutylene terephthalate, polycarbonate resin Resin films, (meth)acrylic resin films, polypropylene resin films, and other films known in the art. 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 phase difference.

(2) A polarizing plate with a film formed by a liquid crystal layer as a polarizing element A polarizing plate provided with a film formed of a liquid crystal layer as a polarizing element will be described. As a film coated with a pigment having absorption anisotropy used as a polarizing element, a composition containing a dichroic pigment having liquid crystallinity or a composition containing a dichroic pigment and a liquid crystal compound can be applied to the substrate. The film obtained by hardening the material and hardening. The film can be used as a polarizing plate after the substrate is peeled off or together with the substrate, or can also be used as a polarizing plate with a protective film on one or both sides of the film. As this protective film, the same thing as the polarizing plate provided with the said stretched film as a polarizing element is mentioned.

The film obtained by coating and hardening the pigment that absorbs anisotropy is preferably thinner, but if it is too thin, the strength decreases and the workability tends to deteriorate. 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.

As a film obtained by coating the pigment|dye which has absorption anisotropy, specifically, the film described in Unexamined-Japanese-Patent No. 2012-33249 etc. is mentioned.

The thickness of a polarizing plate including a film formed of a liquid crystal layer as a polarizing element can be, for example, 1 μm or more and 50 μm or less.

The retardation film described later (for example, a retardation film including a λ/4 plate as a retardation layer) can be laminated on a polarizing plate to obtain a circular polarizing plate. At this time, the angle formed by the absorption axis of the polarizing element and the slow axis of the λ/4 plate can be 45°±10°.

(Touch sensor panel) As a touch sensor panel, as long as it is a sensor that can detect the position being touched, the detection method is not limited. Examples include resistive film method, electrostatic capacitance coupling method, photo sensor method, and ultrasonic method. , Electromagnetic induction coupling method, surface acoustic wave method, etc. touch sensor panel. In terms of low cost, it is suitable to use touch sensor panels of resistive film method and electrostatic capacitance coupling method.

An example of the touch sensor panel of the resistive film method includes: a pair of substrates, which are arranged opposite to each other; an insulating spacer, which is sandwiched between the pair of substrates; and a transparent conductive film, which serves as a resistive film Set on the inner front surface of each substrate; and touch position sensing circuit. In an image display device equipped with a touch sensor panel of a resistive film method, if the surface of the front panel 10 is touched, the opposing resistive film is short-circuited, and current flows through the resistive film. The touch position sensing circuit senses the voltage change at this time, and detects the touched position.

An example of the touch sensor panel of the electrostatic capacitance coupling method includes: a substrate; a transparent electrode for position detection, which is provided on the entire surface of the substrate; and a touch position sensing circuit. In an image display device equipped with a touch sensor panel of an electrostatic capacitance coupling method, if the surface of the front panel 10 is touched, at the touched point, the transparent electrode is grounded via the electrostatic capacitance of the human body. The touch position sensing circuit senses the ground of the transparent electrode and detects the touched position.

The thickness of the touch sensor panel can be, for example, 5 μm or more and 2,000 μm or less, or 5 μm or more and 100 μm or less.

(Retardation film) The retardation film may include one layer or two or more retardation layers. As the retardation layer, a positive A plate or a positive C plate such as a λ/4 plate or a λ/2 plate can be used. The retardation layer may be formed of the resin film exemplified as the material of the above-mentioned protective film, or may be formed of a layer formed by curing a polymerizable liquid crystal compound. The retardation film may further include an alignment film or a base film.

The thickness of the retardation film can be, for example, 1 μm or more and 50 μm or less.

(Colored layer) For example, when the colored layer 40 is used in a display device, it has a function of improving the visibility of the image to be displayed, and preventing the wiring in the display device from being visible from the outside of the display device. Regarding the colored layer 40, for example, the optical density may be 3 or more, preferably 5.0 or more.

The shape and color of the colored layer 40 are not limited, and can be appropriately selected according to the application or design of the display device using the laminate, for example. The colored layer 40 contains a colorant. The colored layer 40 may be composed of only one layer, or may include two or more layers. When the colored layer 40 includes two or more layers, at least one of the two or more layers is a coloring agent-containing layer containing a coloring agent, and the remaining layers may or may not contain a coloring agent. As the color of the coloring agent, black, red, white, dark blue, silver, gold, etc. can be exemplified. The coloring layer 40 may have a coloring agent-containing layer with higher light-shielding properties, a base layer for improving adhesion, or the like under the coloring agent-containing layer containing a coloring agent. In addition, it may have a transparent protective layer covering a colorant-containing layer.

The colorant can be appropriately selected according to the desired color. As the coloring agent, for example, carbon black such as titanium dioxide, zinc white, acetylene black, iron black, red lead, molybdenum cadmium red, ultramarine blue, cobalt blue, chrome yellow, titanium yellow and other inorganic pigments; phthalocyanine blue, indans Lin blue, isoindolinone yellow, benzidine yellow, quinacridone red, polyazo red, perylene red, aniline black and other organic pigments or dyes; metallic pigments containing scaly foils such as aluminum and brass; Contains pearl luster pigments (pearl pigments) coated with scaly foils such as mica and alkaline lead carbonate coated with titanium dioxide. In this specification, the metal contained in the plating layer is also included in the colorant.

Each layer of the colored layer 40 can be formed by a method such as a printing method, a coating method, and a plating method. The colored layer 40 may be partially formed on the surface of the back plate 30 on the side of the adhesive layer 20, and the colored layer 40 may also be partially formed on the surface of the front panel 10 on the side of the adhesive layer 20. The colored layer 40 can be directly formed on the surface of the front panel 10 on the side of the adhesive layer 20 or on the surface of the back panel 30 on the side of the adhesive layer 20, or the one formed on other substrates can be transferred to the front panel 10 is formed on the surface of the adhesive layer 20 side or the back plate 30 is formed on the surface of the adhesive layer 20 side. Specific examples of the printing method include gravure printing, offset printing, screen printing, and transfer printing from a transfer sheet. It is also possible to repeatedly perform printing using a printing method to obtain a coloring layer 40 of a desired thickness. Examples of inks used in the printing method include inks containing colorants, binders, solvents, optional additives, and the like. From the viewpoint of reducing the level difference, the colored layer 40 is preferably partially formed on the surface of the back plate 30 on the second adhesive layer 22 side.

Examples of the binder include: chlorinated polyolefins (for example, chlorinated polyethylene, chlorinated polypropylene), polyester resins, urethane resins, acrylic resins, vinyl acetate resins, and vinyl chloride resins. Vinyl acetate copolymer, cellulose resin. The binder resin may be used alone, or two or more types may be used in combination. The binder resin may be a thermopolymerizable resin or a photopolymerizable resin.

When forming a coloring agent-containing layer by a printing method, it is preferable to use an ink containing 50 parts by mass or more and 200 parts by mass or less of the coloring agent with respect to 100 parts by mass of the binder resin.

Specific examples of the plating method include known plating methods such as electrolytic plating, electroless plating, hot-dip plating, chemical vapor deposition, and physical vapor deposition. Examples of physical vapor deposition include: vacuum vapor deposition, molecular beam vapor deposition, ion beam vapor deposition, and other evaporation systems including methods for heating the evaporation source to evaporate; sputtering systems such as magnetron sputtering and ion beam sputtering. These methods can be combined with patterning as needed. In this specification, the layer formed by the plating method is referred to as a plating layer.

When the colored layer 40 is provided on the periphery of the front panel 10 or the back panel 30, the shape of the entire periphery of the periphery is not limited, and it may be provided only on the periphery according to the desired design, etc. Part of the form. When the colored layer 40 is provided on the periphery of the front panel 10 or the back panel 30, its width can be appropriately determined according to the size of the display area, the desired design, etc., for example, it is preferably 1 mm or more and 20 mm or less range.

The thickness of the colored layer 40 may be, for example, 50 μm or less, preferably 30 μm or less, and more preferably 25 μm or less. By making the thickness of the colored layer 40 within the above-mentioned numerical range, there is a tendency to easily suppress bubbles generated at the interface with the adhesive layer. The thickness of the colored layer 40 may be, for example, 0.1 μm or more, preferably 3 μm or more. By making the thickness of the colored layer 40 to be 0.1 μm or more, the colored layer 40 is easily visible, which contributes to the improvement of designability, and also contributes to the improvement of optical density.

In FIG. 1, a case where the thickness of the colored layer 40 is uniform and the cross-sectional shape is rectangular is illustrated. However, the thickness of the colored layer 40 may also be non-uniform. For example, the cross-sectional shape may have an inclined portion whose thickness becomes thinner toward the inside. By having the inclined part, there is a tendency to easily suppress the trapping of air that is easily generated during lamination. When the thickness of the colored layer 40 is not uniform, the numerical range described as the thickness of the colored layer 40 in the above is set to the maximum thickness of the colored layer 40.

＜Display device＞ A display device of another aspect of the present invention includes a laminated body 100. The laminated body 100 can be arranged on the visible side of the display device so that the front panel becomes the outer side. The display device is not particularly limited, and examples thereof include organic electroluminescence (organic EL) display devices, inorganic electroluminescence (inorganic EL) display devices, liquid crystal display devices, electroluminescence display devices, and the like. The display device may also have a touch panel function. The laminated body 100 is suitable for a display device having flexibility.

＜Manufacturing method of laminated body＞ The first embodiment of the method of manufacturing the laminate 100 includes the following steps. 1) The step of partially forming a colored layer 40 on one surface of the back plate 30 (Figure 2(a)) 2) The step of preparing the second adhesive sheet 60 having the second adhesive layer 22 between the release film 61 and the release film 62 (Figure 2(b)) 3) The step of peeling off the release film 62 and bonding the second adhesive sheet 60 to the surface of the back plate 30 on the side of the colored layer 40 (Figure 2(c)) 4) The step of preparing the first adhesive sheet 70 with the first adhesive layer 21 between the release film 71 and the release film 72 (Figure 2(d)) 5) The step of bonding the second adhesive layer 22 of the second adhesive sheet 60 after the release film 61 is peeled off and the first adhesive layer 21 of the first adhesive sheet 70 after the release film 72 is peeled off (Figure 2( e)) 6) The step of peeling off the peeling film 71 and pasting the front panel 10 on the surface of the first adhesive layer 21 (Figure 2(f))

The second embodiment of the method of manufacturing the laminate 100 includes the following steps. 1) The step of partially forming a colored layer 40 on one surface of the back plate 30 (Figure 3(a)) 2) The step of preparing the second adhesive sheet 60 having the second adhesive layer 22 between the release film 61 and the release film 62 (Figure 3(b)) 3) The step of peeling off the release film 62 and bonding the second adhesive sheet 60 to the surface of the back plate 30 on the side of the colored layer 40 (Figure 3(c)) 4) The step of preparing the first adhesive sheet 70 with the first adhesive layer 21 between the release film 71 and the release film 72 (Figure 3(d)) 5) The step of peeling off the peeling film 72 and pasting the first adhesive sheet 70 on the surface of the front panel 10 (Figure 3(e)) 6) The step of bonding the second adhesive layer 22 of the second adhesive sheet 60 after the release film 61 is peeled off and the first adhesive layer 21 of the first adhesive sheet 70 after the release film 71 is peeled off (Figure 3( f))

When the first adhesive layer 21 and the second adhesive layer 22 are laminated, or when the adhesive layer 20 is bonded to the front panel 10 or the back panel 30, corona treatment, plasma treatment, etc. can be applied to the bonding surface deal with.

The first adhesive sheet 70 and the second adhesive sheet 60 can be produced, for example, by dissolving or dispersing the adhesive composition in an organic solvent such as toluene or ethyl acetate to prepare an adhesive liquid, and subjecting it to a mold release treatment. The release film 71 or 72 and the release film 61 or 62 are formed into a sheet-like layer containing an adhesive, and another release film 72 or 71 and the release film 62 or 61 are further attached to the adhesive layer.

In the first and second embodiments of the manufacturing method of the laminate 100, in step 1), the colored layer 40 may be partially formed on one surface of the front panel 10, instead of partially forming the colored layer 40 on the back panel One of 30 is on the surface.

Examples and comparative examples are shown below to describe the present invention more specifically, but the present invention is not limited by these examples. [Example]

＜Thickness＞ Use a laser cutter to cut the laminate. A transmission electron microscope (SU8010; Horiba Manufacturing Co., Ltd.) was used to observe the cross section of the cut laminate, and the thickness of each layer was measured from the obtained observation image.

＜Storage modulus＞ A rheometer (Anton Parr, MCR-301) was used to measure the storage modulus (G') of a sample formed by stacking the adhesive layer to become 150 μm under the following conditions. Conditions: stress is 1%, frequency is 1 Hz

<Loss Tangent> Using a rheometer (Anton Parr, MCR-301), under the following conditions, the sample formed by stacking the adhesive layer to be 150 μm was measured for Tanδ. Conditions: stress is 1%, frequency is 1 Hz

＜Flexibility＞ After fixing the laminate to a bending tester (Covotech, CFT-720C), the window film is positioned on the inside, and the bending test is performed so that the distance between the films when bending becomes 6 mm. Thereafter, based on the number of bending when cracks are generated in the bending part or when the adhesive swells, the judgment is made as follows. ◎: more than 200,000 times, ○: more than 100,000 times and less than 200,000 times, ×: less than 100,000 times

＜Bubble evaluation＞ Place the laminate in an oven at 85°C and 85% humidity for about 1 hour and then take it out. Use an optical microscope to observe the step area of the step area of the colored layer in an area of 1 cm×1 cm, and count the number of bubbles with a size of 10 μm or more. Furthermore, the number in the row of "Bubble presence" in Table 1 indicates the number of bubbles. ○: 10 or less, ×: more than 10

Production Example 1-1 (Acrylic Copolymer A1) Into a 500 ml four-neck reactor with refluxing nitrogen and equipped with a cooling device for easy temperature adjustment, 25 parts by weight of 4-hydroxybutyl acrylate (4-HBA) and 2-ethylhexyl acrylate (2 -EHA) 50 parts by weight, 15 parts by weight of methyl acrylate (MA), and 10 parts by weight of isopropyl acrylate (IBOA), and then 100 parts by weight of ethyl acetate (EAc) as a solvent were added. Thereafter, after purging with nitrogen for 1 hour to remove oxygen, the temperature was maintained at 60°C. After making the above-mentioned mixture uniform, 0.07 parts by mass of azobisisobutyronitrile (AIBN) as a reaction initiator was added with respect to 100 parts by mass of the above-mentioned mixture. The reaction is about 5 hours to produce acrylic copolymer A1 with a weight average molecular weight of about 800,000.

Production Example 1-2 (Acrylic Copolymer A2) Except for using butyl acrylate (BA) instead of methyl acrylate (MA), the acrylic copolymer A2 was produced in the same manner as in Production Example 1-1.

Production Example 1-3 (Acrylic Copolymer A3) Except having used hexyl acrylate (HA) instead of methyl acrylate (MA), the acrylic copolymer A3 was produced in the same manner as in Production Example 1-1.

Production Example 1-4 (Acrylic Copolymer A4) Except for using lauryl acrylate (LA) instead of methyl acrylate (MA), the acrylic copolymer A4 was produced in the same manner as in Production Example 1-1.

Production Example 2-1 (Acrylic Copolymer B1) Into a 500 ml four-necked reactor equipped with refluxing nitrogen and equipped with a cooling device for easy temperature adjustment, 20 parts by mass of methyl acrylate (MA) and 40 parts by mass of 4-hydroxybutyl acrylate (4-HBA) were put into each After 40 parts by mass of octyl acrylate (OA), nitrogen flushing was performed for 1 hour to remove oxygen, and then maintained at 80°C. After the above-mentioned mixture is uniformly mixed, 3 parts by mass of hydroxycyclohexylphenyl ketone, which is a reactive photoinitiator, is added to the above-mentioned mixture. After that, ultraviolet rays (10 mW) were irradiated while stirring to produce acrylic copolymer B1.

Production Example 2-2 (Acrylic Copolymer B2) Except having used 2-ethylhexyl acrylate (2-EHA) instead of methyl acrylate (MA), the acrylic copolymer B2 was produced in the same manner as in Production Example 2-1.

Production Example 2-3 (Acrylic Copolymer B3) Except for using lauryl acrylate (LA) instead of methyl acrylate (MA), the acrylic copolymer B3 was produced in the same manner as in Production Example 2-1.

(The first adhesive sheet) On the release film coated with a silicon release agent, coat 0.5 parts by mass of a crosslinking agent (CORONATE-L, Tosoh Co., Ltd.) relative to 100 parts by mass of the acrylic copolymer shown in Table 1 The mixture. The applied mixture was dried at 100°C for 1 minute. The thickness after drying is 25 μm. The first adhesive sheet (177 mm in length×105 mm in width) was produced by bonding the release film thereon.

(Second Adhesive Sheet) On the release film coated with silicon release agent, apply 10 parts by mass of reactive diluent (isodecyl acrylate) to 100 parts by mass of the acrylic copolymer shown in Table 1 and photopolymerize it. A mixture of 0.1 parts by mass of the starting agent (hydroxycyclohexyl phenyl ketone). A high-pressure mercury UV (ultraviolet, ultraviolet) lamp was used to irradiate the amount of light shown in Table 1 to obtain a second adhesive sheet (length 177 mm × width 105 mm) with a thickness of 25 μm.

(Preparation of composition for forming colorant-containing layer (black)) [Ink composition] Acetylene black 15 mass% Polyester 75% by mass Dimethyl glutarate 2.5% by mass Succinic acid 2 mass% Isophorone 5.5 mass% [hardener] Aliphatic polyisocyanate 75% by mass Ethyl acetate 25% by mass [Solvent] Isophorone [Preparation] With respect to 100 parts by mass of the ink components, 10 parts by mass of a curing agent and 10 parts by mass of a solvent were added and stirred to obtain a composition for forming a colorant-containing layer (black).

(Preparation of protective layer forming composition (transparent)) [Ink composition] Polyester 90% by mass Dimethyl glutarate 2.5% by mass Succinic acid 2 mass% Isophorone 5.5 mass% [hardener] Aliphatic polyisocyanate 75% by mass Ethyl acetate 25% by mass [Solvent] Isophorone [Preparation] With respect to 100 parts by mass of the ink components, 10 parts by mass of the curing agent and 10 parts by mass of the solvent were added and stirred to obtain a composition for forming a protective layer.

(Front panel) As the front panel, a 70 μm-thick window film with a hard coat layer formed on both sides of the base film (base film is 50 μm, each hard coat layer is 10 μm, length 177 mm × width 105 mm) is prepared. The base film of the window film is a polyimide-based resin film, and the hard coat layer is a layer formed of a composition containing a dendrimer compound having a polyfunctional acryl group at its terminal.

(Back panel) As the back plate, a circular polarizing plate produced as follows was used. After the photo-alignment film is formed on the substrate, the composition containing the dichroic dye and the polymerizable liquid crystal compound is applied to the substrate, aligned and cured to obtain a polarizing element with a thickness of 2 μm. On the polarizing element, a triacetyl cellulose (TAC) film with a thickness of 25 μm was bonded via an adhesive layer. On the exposed surface after peeling off the substrate, attach a retardation film (thickness 17 μm) containing a layer formed by polymerizing and hardening the liquid crystal compound (thickness: 17 μm, layer composition: overcoat layer (hardened layer of acrylic resin composition, thickness 1 μm)/Adhesive layer (thickness of 5 μm)/Lambda/4 plate (thickness of 3 μm) containing liquid crystal compound hardened layer and alignment film/Adhesive layer (thickness of 5 μm)/Liquid crystal compound hardened The resulting layer and the positive C plate of the alignment film (thickness 3 μm)). The circular polarizing plate ("TAC/polarizing element/phase difference film" layer structure, thickness 44 μm, length 177 mm × width 105 mm) made in this way was prepared as a back plate. Furthermore, the angle formed by the absorption axis of the polarizing element and the slow axis of the λ/4 plate is 45°.

(Layered body) After peeling off the release film of one of the second adhesive sheets, corona treatment is performed on the exposed second adhesive layer.

On the surface of the TAC of the circular polarizer, use the coloring agent-containing layer forming composition (black) prepared in the above as the ink, and use a 460 mesh screen to use screen printing, and the coating thickness after drying becomes 3 μm In the non-display area, a black printing layer with a thickness of 3 μm and a width of 5 mm is formed.

On the TAC surface of the circular polarizing plate with the black printing layer, an electron beam evaporation device (product name: UNIVAC 2050, manufactured by UNIVAC) was used to form an evaporation layer with a thickness of 80 Å _{using TiO 2 as the evaporation source.} On the top, In is used as the vapor deposition source to form a 500 Å thick vapor deposition layer, on top of which, TiO _{2 is} used as the vapor deposition source to form a 150 Å thick vapor deposition layer, on which Al ₂ O _{3 is} used as the vapor deposition layer. Plating source to form an evaporated layer of 150 Å thickness. In this way, a golden vapor deposition layer (plating layer, thickness <1 μm) including 4 layers is formed in the entire area including the non-display area and the display area. Then, on the non-display area on the surface of the golden vapor deposition layer, use the protective layer forming composition (transparent) prepared above as ink, and use a 460 mesh screen to use screen printing, and the coating thickness after drying becomes Printing with a spray volume of 5 μm to form a protective layer, and then use etching to remove the golden vapor-deposited layer in the area (display area) where the protective layer is not formed. In this way, in the non-display area, a layer structure of "black printing layer (thickness of 3 μm)/golden vapor deposition layer (thickness <1 μm)/protective layer (thickness of 5 μm)" is formed (the overall thickness exceeds 8 μm and no Up to 9 μm) coloring layer 40.

Perform corona treatment on the surface of the black printed layer side of the circular polarizer. The second adhesive layer is bonded to the circular polarizing plate so that the corona-treated surface becomes the bonding surface.

After peeling off the other release film of the second adhesive sheet, corona treatment is applied to the exposed second adhesive layer. Perform corona treatment on the first adhesive layer in the first adhesive sheet. The second adhesive layer and the first adhesive layer are bonded so that the corona-treated surface becomes the bonding surface.

The release film was peeled from the first adhesive sheet, and the exposed first adhesive layer was subjected to corona treatment. Corona treatment is applied to one side of the above-mentioned window film. The first adhesive layer is bonded to the window film so that the corona-treated surface becomes the bonding surface.

In this way, a laminated body including the window film/the first adhesive layer/the second adhesive layer/the circular polarizing plate was produced.

The corona treatment was carried out under the following conditions. Frequency: 20 kHz/ Voltage: 8.6 kV/ Power: 2.5 kW/ Speed: 6 m/min

[Table 1] Table 1 Adhesive sheet 1 Adhesive sheet 2 effect Acrylic copolymer (A) Crosslinking agent (parts by mass) Storage modulus (MPa) Tanδ Acrylic copolymer (B) Reactive diluent (parts by mass) Photopolymerization initiator (parts by mass) Tanδ UV radiation (mJ/cm ² ) Storage modulus (MPa) Flexibility Whether there are bubbles Example 1 A2 0.5 0.08 0.30 B2 10 0.1 0.55 500 0.02 ◎ ○(0) Example 2 A2 0.5 0.08 0.30 B3 10 0.1 0.75 500 0.01 ◎ ○(1) Example 3 A3 0.5 0.02 0.70 B2 10 0.1 0.55 500 0.02 ○ ○(0) Example 4 A3 0.5 0.02 0.70 B3 10 0.1 0.75 500 0.01 ○ ○(0) Comparative example 1 A1 0.5 0.30 0.10 B1 10 0.1 0.35 500 0.06 X ×(≧30) Comparative example 2 A4 0.5 0.006 1.30 B1 10 0.1 0.35 600 0.07 X ×(24) Comparative example 3 A2 0.5 0.08 0.30 B1 10 0.1 0.35 1000 0.12 X ×(≧30) Comparative example 4 A4 0.5 0.006 1.30 B2 10 0.1 0.55 800 0.05 X ×(15)

＜Compression modulus of elasticity＞ A measurement sample (50 mm×50 mm in size) was cut out from the adhesive layer used in each of the Examples and Comparative Examples. For the measurement samples, in accordance with ISO-FDIS 14577-12013 (E), use a micro hardness tester (manufactured by Helmut Fischer, HM-500, indenter type: diamond square pyramid), and the indenter's indentation direction is relative to the measurement The test was performed in the following manner at a measurement temperature of 25°C so that the main surface of the sample (the surface perpendicular to the thickness direction) became vertical. Furthermore, when the indenter's indentation direction is perpendicular to the side surface of the measurement sample (a surface parallel to the thickness direction), the measured value is also the same as the indenter's indentation direction. The same is true when the measurement is performed so that it is perpendicular to the main surface of the sample for measurement. After the indenter is in contact with the sample for measurement, a load is applied, and after reaching the set test force (1 mN), it is unloaded after being held for 5 seconds. According to the stress-strain curve obtained during unloading, obtain the slope of the tangent line under the maximum test force and set it as the compressive elastic modulus (E'=δ/ε). The results are shown in Table 2.

[Table 2] Table 2 Example Comparative example 1 2 3 4 1 2 3 4 Compression modulus of elasticity (MPa) 1st adhesive layer 10 10 4 4 15 1 10 1 2nd adhesive layer 5 3 5 3 7 8 13 6

10: Front panel 20: Adhesive layer 21: The first adhesive layer 22: The second adhesive layer 30: back panel 40: Colored layer 60: The second adhesive sheet 61: peeling film 62: peeling film 70: The first adhesive sheet 71: peeling film 72: peeling film 100: layered body

Fig. 1 is a schematic cross-sectional view showing an optical laminate of one aspect of the present invention. 2(a) to (f) are schematic cross-sectional views schematically showing a laminated body of the method of manufacturing a laminated body of the present invention. 3(a) to (f) are schematic cross-sectional views schematically showing a laminated body of the method of manufacturing a laminated body of the present invention.

10: Front panel

20: Adhesive layer

21: The first adhesive layer

22: The second adhesive layer

30: back panel

40: Colored layer

100: layered body

Claims (7)

An optical laminate in which a front panel, an adhesive layer, and a back panel are sequentially laminated, and the coloring layer is partially formed on either the adhesive layer side of the front panel or the adhesive layer side of the back panel , The adhesive layer includes a first adhesive layer and a second adhesive layer, and is laminated so that the second adhesive layer becomes the colored layer side, The adhesive layer is arranged so as to cover at least the inner end of the colored layer in the plan view of the optical laminate, The first adhesive layer and the second adhesive layer include (meth)acrylic resin, and Meet the following (1) and (2): (1) 0.01 MPa≦The storage modulus of the first adhesive layer and the second adhesive layer≦0.1 MPa; (2) 0.5≦The loss tangent of the second adhesive layer≦0.8. The optical laminate of claim 1, wherein the loss tangent of the first adhesive layer is different from the loss tangent of the second adhesive layer. The optical laminate of claim 1 or 2, wherein the thickness of the second adhesive layer is greater than the thickness of the colored layer. The optical laminate according to any one of claims 1 to 3, wherein the total thickness of the first adhesive layer and the second adhesive layer is 25 μm or more and 150 μm or less. A display device comprising the optical laminate according to any one of claims 1 to 4. The optical laminate according to any one of claims 1 to 4, wherein the compressive elastic modulus of the first adhesive layer is 3 MPa or more and 12 MPa or less. The optical laminate according to any one of claims 1 to 4 and 6, wherein the compression elastic modulus of the second adhesive layer is 3 MPa or more and 5 MPa or less.

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