JP2021152644A - Flexible laminate and image display device having the same - Google Patents

Abstract

To provide a flexible laminate with superior bending resistance.SOLUTION: A flexible laminate comprises a front plate, a first adhesive layer, a circularly polarizing plate, a second adhesive layer, a touch sensor layer, and a third adhesive layer arranged in the described order. The third adhesive layer includes at least a 3A adhesive layer and a 3B adhesive layer. The 3A adhesive layer is in contact with the touch sensor layer. A storage modulus GA' of the 3A adhesive layer and a storage modulus GB' of the 3B adhesive layer satisfy a relationship expressed as GA'/GB'≥1. A thickness dA of the 3A adhesive layer and a thickness dB of the 3B adhesive layer satisfy a relationship expressed as dA/dB≤1.SELECTED DRAWING: Figure 1

Description

The present invention relates to a flexible laminate and an image display device including the flexible laminate.

Japanese Unexamined Patent Publication No. 2006-053531 (Patent Document 1) and International Publication No. 2010/0442229 (Patent Document 2) include a transparent adhesive or an adhesive applied to bond transparent panels such as an image display panel. The sheet is disclosed.

Japanese Unexamined Patent Publication No. 2006-053531 International Publication No. 2010/0442229

Further thinning is required for a flexible laminate of a method (so-called in-folding method) in which the front plate is bent so as to be inside, and an image display device provided with the flexible laminate. However, when the laminate is further thinned, cracks tend to occur in the touch sensor layer in the laminate when the laminate is repeatedly bent so that the front plate is on the inside. Was found. Therefore, it is required that the laminated body has bending resistance, which means resistance to the occurrence of cracks in the touch sensor layer.

In view of the above circumstances, an object of the present invention is to provide a flexible laminate having excellent bending resistance when the front plate is repeatedly bent so as to be inside, and an image display device provided with the flexible laminate.

The present invention provides the following flexible laminate and an image display device including the following flexible laminate.
[1] A flexible laminate including a front plate, a first pressure-sensitive adhesive layer, a circularly polarizing plate, a second pressure-sensitive adhesive layer, a touch sensor layer, and a third pressure-sensitive adhesive layer in this order.
The third pressure-sensitive adhesive layer includes at least a third A pressure-sensitive adhesive layer and a third B pressure-sensitive adhesive layer.
The third A adhesive layer is in contact with the touch sensor layer, and is in contact with the touch sensor layer.
The 'storage modulus of the first 3B adhesive layer G _B' the 3A adhesive layer storage modulus G _A and satisfies G _A '/ G _B' ≧ 1 relationship,
A flexible laminate in which the thickness dA of the third A pressure-sensitive adhesive layer and the thickness dB of the third B pressure-sensitive adhesive layer satisfy the relationship of dA / dB ≦ 1.

[2] the first 3A storage modulus of the pressure-sensitive adhesive layer G _A 'is 0.1MPa or more, the flexible laminate according to [1].

[3] The flexible laminate according to [1] or [2], wherein the thickness dA of the third A pressure-sensitive adhesive layer is 25 μm or less.

[4] An image display device comprising the flexible laminate according to any one of [1] to [3] and having a back plate arranged on the third pressure-sensitive adhesive layer side.

[5] The image display device according to [4], wherein the image display device has a limit bending number of 200,000 times or more in a flexibility test in which the front plate is bent so as to be inside.

According to the above, it is possible to provide a flexible laminate having excellent bending resistance when the front plate is repeatedly bent so as to be inside, and an image display device provided with the flexible laminate.

It is schematic cross-sectional view which shows typically an example of the flexible laminated body of this invention. It is a schematic cross-sectional view which shows typically an example of the image display device of this invention. It is the schematic explaining the method of a flexibility test.

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 drawings below, the scales are appropriately adjusted to make each component easier to understand, and the scale of each component shown in the drawings does not necessarily match the scale of the actual component. Further, in the present specification, "flexibility" in the case of repeatedly bending with the front plate side inward will be described using the term "inner bending flexibility".

[Flexible laminate]
While advancing the development of a flexible laminate applied to a so-called infolding type image display device, the present inventors have a touch sensor (so-called base) that does not have a resin film as a base material in order to further reduce the thickness. We paid attention to the adoption of a materialless touch sensor). However, it has been found that in the flexible laminate using the base material-less touch sensor, cracks are likely to occur in the touch sensor when the front plate is repeatedly bent so as to be inside.

As a result of diligent studies based on the above findings, the present inventors have come up with the idea of imparting a property such as increasing the storage elastic modulus of the pressure-sensitive adhesive layer in contact with the touch sensor. As a result, even when the front plate is repeatedly bent so as to be inside, it is difficult for the touch sensor to generate cracks, and a flexible laminate having excellent inward bending flexibility and an image display provided with the flexible laminate are provided. The device was reached and the present invention was completed.

Hereinafter, the flexible laminate of one embodiment according to the present invention will be described with reference to FIG. 1 and the like. FIG. 1 is a schematic cross-sectional view schematically showing an example of a flexible laminated body according to the present embodiment.

As shown in FIG. 1, the flexible laminate 100 according to the present embodiment includes a front plate 10, a first adhesive layer 20, a circularly polarizing plate 30, a second adhesive layer 40, and a touch sensor layer (hereinafter, “TS layer”). (Also also referred to as) 50 and the third pressure-sensitive adhesive layer 60 are included in this order. The third pressure-sensitive adhesive layer 60 includes at least a third A pressure-sensitive adhesive layer 61 and a third B pressure-sensitive adhesive layer 62. Further, the third A pressure-sensitive adhesive layer 61 is in contact with the TS layer 50. In other words, the flexible laminate 100 constitutes the front plate 10, the first pressure-sensitive adhesive layer 20, the circularly polarizing plate 30, the second pressure-sensitive adhesive layer 40, the TS layer 50, and the third pressure-sensitive adhesive layer 60 from the visual side. The 3A pressure-sensitive adhesive layer 61 and the third B pressure-sensitive adhesive layer 62 are laminated in this order.

In the flexible laminate 100, the storage modulus of the 3A adhesive layer 61 G _A 'and the 3B storage modulus G _B of the adhesive layer 62' and satisfies _{G A '/ G B' ≧} 1 relationship. Further, the thickness dA of the third A pressure-sensitive adhesive layer 61 and the thickness dB of the third B pressure-sensitive adhesive layer 62 satisfy the relationship of dA / dB ≦ 1.

The flexible laminate 100 having such characteristics is excellent in internal resistance because cracks are unlikely to occur in the TS layer 50 when the front plate 10 of the image display device to which the flexible laminate 100 is applied is repeatedly bent so as to be inside. It can be provided with bending flexibility. Specifically, even when the front plate 10 of the image display device is bent at least 200,000 times so as to be inside, it is possible to prevent the TS layer 50 from being cracked.

The reason why the flexible laminate 100 can have excellent inward bending flexibility is not clear in detail, but it is considered to be due to the following mechanism. First, regarding an image display device including this type of flexible laminate, when the front plate is bent so as to be inside, tensile stress is generated on the side opposite to the front plate side of the TS layer, which is caused by the tensile stress. Therefore, it is considered that cracks occur in the TS layer. Therefore, in order to prevent cracks from occurring in the TS layer, it is considered desirable to arrange the member that opposes the above tensile stress on the side opposite to the front plate side of the TS layer.

On the other hand, in the flexible laminate 100 according to the present embodiment, the third A pressure-sensitive adhesive layer 61 is arranged in contact with the TS layer 50 on the side opposite to the front plate 10 side of the TS layer 50. The storage modulus G _A of the 3A adhesive layer 61 'is the 3B storage modulus of the pressure-sensitive adhesive layer 62 G _B' is greater than or equal to, harder adhesive layer in contact with the TS layer 50 It can be understood that it is arranged. That is, in the flexible laminate 100, the above-mentioned tensile stress can be countered by the third A pressure-sensitive adhesive layer 61, which is a harder pressure-sensitive adhesive layer. From the above, it is considered that the flexible laminated body 100 and the image display device including the flexible laminated body 100 can be provided with excellent inward bending flexibility.

Specifically, the storage modulus G _A of the 3A adhesive layer 61 'is preferably 0.1MPa or more. The 3A storage modulus G _A pressure-sensitive adhesive layer 61 'is more preferably not less than 0.25 MPa, further preferably 0.5MPa or more, even more preferably 1MPa or more. The 3A storage modulus G _A pressure-sensitive adhesive layer 61 'is preferably as is a large value, since a pressure-sensitive adhesive layer above storage modulus G _A' that is usually less than 10 MPa, 2.0 MPa The following is preferable.

Since the flexible laminate 100 has excellent inward bending flexibility as described above, it can be applied to an image display device (flexible display) capable of bending or winding. In particular, the flexible laminate 100 can be excellent in inward bending and bending resistance when applied to an image display device that employs a so-called in-folding method in which the front plate 10 is bent so as to be inside. As shown in Examples described later, the image display device can have a limit bending number of 200,000 times or more in a flexibility test in which the front plate 10 is bent so as to be inside. The limit bending number is preferably 200,000 times or more, and more preferably 400,000 times or more. Here, the "limit number of bends" is the number of times the flexible laminate 100 can be bent before the TS layer 50 in the bent region of the flexible laminate 100 can be visually confirmed even at one place. means. The flexibility test can be performed by using the method of the examples described later.

Further, since the flexible laminate 100 includes a circular polarizing plate 30, when applied to an image display device, it can also be used as an antireflection film in, for example, an organic electroluminescence (EL) display device.

Here, since the thickness dA of the third A pressure-sensitive adhesive layer 61 is thinner than or the same as the thickness dB of the third B pressure-sensitive adhesive layer 62, the inward bending flexibility of the flexible laminate 100 can be improved. Specifically, the thickness dA of the third A pressure-sensitive adhesive layer 61 is preferably 25 μm or less, more preferably 15 μm or less, and further preferably 10 μm or less. The total thickness dB of the third A pressure-sensitive adhesive layer 61 and the thickness dB of the third B pressure-sensitive adhesive layer 62 is preferably 20 μm or more, more preferably 30 μm or more, and more preferably 40 μm, from the viewpoint of enhancing impact resistance. The above is more preferable. On the other hand, from the viewpoint of increasing the flexibility of the flexible laminated body 100, the total thickness dB of the third A pressure-sensitive adhesive layer 61 and the thickness dB of the third B pressure-sensitive adhesive layer 62 is preferably 100 μm or less, and preferably 80 μm or less. Is more preferable.

Further, from the viewpoint of increasing the flexibility of the flexible laminated body 100, it is also preferable to reduce the thickness of the layer (for example, the front plate 10, the circularly polarizing plate 30 and the like) arranged on the visual side of the TS layer 50. For example, the thickness of the layer arranged on the visual side of the TS layer 50 is preferably 500 μm or less, more preferably 300 μm or less, and further preferably 200 μm or less. On the other hand, from the viewpoint of providing impact resistance, it is preferable that the thickness of the layer arranged on the visual side of the TS layer 50 is a certain thickness. For example, the thickness of the layer arranged on the visual side of the TS layer 50 is preferably 50 μm or more, more preferably 80 μm or more, and may be 100 μm or more.

The shape of the flexible laminate 100 in the plane direction is not particularly limited, but it is preferably a square shape, and more preferably a rectangular shape. When the flexible laminate 100 has a rectangular shape, the length of the long side is preferably, for example, 50 mm to 300 mm, may be 100 mm to 280 mm, and the length of the short side is, for example, 30 mm to 250 mm. It is preferably 60 mm to 220 mm. The flexible laminated body 100 may be a square shape having rounded corners in which at least one of the corners of the square shape is R-processed, or may be a square shape having a notch on at least one side. The flexible laminated body 100 may be provided with a hole portion penetrating in the laminating direction. The thickness of the flexible laminate 100 varies depending on the functions and applications required for the flexible laminate 100, but can be 20 μm or more and 2000 μm or less, preferably 50 μm or more and 500 μm or less.

<Front plate>
The front plate 10 is a plate-like body capable of transmitting light, and can function as a layer for protecting a display element or the like of an image display device. The front plate 10 can be a layer constituting the outermost surface of the image display device. The front plate 10 is usually preferably made of resin or glass. The front plate 10 is preferably a resin film, or a resin film with a hard coat layer or a glass film in which a hard coat layer is provided on at least one surface of the resin film to further improve the hardness. The front plate 10 may have a blue light cut function, a viewing angle adjusting function, and the like.

The resin film forming the front plate 10 is not limited as long as it is a resin film capable of transmitting light. For example, triacetyl cellulose, acetyl cellulose butyrate, ethylene-vinyl acetate copolymer, propionyl cellulose, butyryl cellulose, acetyl propionyl cellulose, polyester, polystyrene, polyamide, polyetherimide, poly (meth) acrylic, polyimide, polyethersulfone. , Polysulfone, polyethylene, polypropylene, polymethylpentene, polyvinyl chloride, polyvinylidene chloride, polyvinyl alcohol, polyvinyl acetal, polyether ketone, polyether ether ketone, polyether sulfone, polymethyl (meth) acrylate, polyethylene terephthalate, polybutylene terephthalate. , Polysulfone, polycarbonate, polyamideimide and other polymers. These polymers can be used alone or in admixture of two or more. The front plate 10 is made of a polymer such as polyimide, polyamide, or polyamide-imide which has excellent flexibility and can be configured to have high strength and high transparency when the image display device is a flexible display. Resin film is preferably used.

The resin film with a hard coat layer forming the front plate 10 may have a hard coat layer on one surface of the resin film, or may have a hard coat layer on both sides of the resin film. When the hard coat layers are provided on both sides of the resin film, the composition and thickness of each hard coat layer may be the same or different from each other. The resin film with a hard coat layer can improve hardness and scratch resistance as compared with a resin film having no hard coat layer.

The hard coat layer of the resin film with a hard coat layer is, for example, a cured layer of an ultraviolet curable resin. Examples of the ultraviolet curable resin include (meth) acrylic resins such as monofunctional (meth) acrylic resins, polyfunctional (meth) acrylic resins, and polyfunctional (meth) acrylic resins having a dendrimer structure; silicone resins. ; Polyester resin; Urethane resin; Amid resin; Epoxy resin and the like can be mentioned. The hard coat layer may contain additives to improve strength. The type of additive is not limited, and examples thereof include inorganic fine particles, organic fine particles, and mixtures thereof.

The thickness of the front plate 10 may be, for example, 20 μm or more and 500 μm or less, preferably 30 μm or more and 200 μm or less, and more preferably 40 μm or more and 100 μm or less.

<First adhesive layer>
The first pressure-sensitive adhesive layer 20 is a layer for bonding the front plate 10 and the circularly polarizing plate 30, and can be formed by using a conventionally known pressure-sensitive adhesive composition. For example, the first pressure-sensitive adhesive layer 20 can be composed of a pressure-sensitive adhesive composition containing (meth) acrylic-based, rubber-based, urethane-based, ester-based, silicone-based, polyvinyl ether-based resins and the like as main components. Among them, a pressure-sensitive adhesive composition using a (meth) acrylic resin having excellent transparency, weather resistance, heat resistance and the like as a base polymer is preferable. The pressure-sensitive adhesive composition may be either 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 2-ethylhexyl (meth) acrylate. A polymer or a copolymer containing one or more of (meth) acrylic acid esters as monomers is preferably used. It is preferable that the base polymer is copolymerized with a polar monomer. Examples of the polar monomer include (meth) acrylic acid, 2-hydroxypropyl (meth) acrylate, hydroxyethyl (meth) acrylate, (meth) acrylamide, N, N-dimethylaminoethyl (meth) acrylate, and glycidyl (meth). ) Monomers having a carboxyl group such as acrylate, a hydroxyl group, an amide group, an amino group, an epoxy group and the like can be mentioned. As used herein, the term "(meth) acrylic resin" refers to at least one selected from the group consisting of acrylic resins and methacrylic resins. The same applies to other terms with "(meta)".

The pressure-sensitive adhesive composition may contain only the above-mentioned base polymer, but usually can further contain a cross-linking agent. As a cross-linking agent, a divalent or higher valent metal ion that forms a carboxylic acid metal salt with a carboxyl group; a polyamine compound that forms an amide bond with the carboxyl group; an ester bond is formed with the carboxyl group. Polyepoxy compounds or polyols; polyisocyanate compounds that form an amide bond with a carboxyl group are exemplified. Of these, polyisocyanate compounds are preferable.

The active energy ray-curable pressure-sensitive adhesive composition refers to a pressure-sensitive adhesive composition having a property of being cured by being irradiated with active energy rays such as ultraviolet rays and electron beams. The active energy ray-curable pressure-sensitive adhesive composition has adhesiveness even before irradiation with active energy rays and can be adhered to an adherend such as a film. The force can be adjusted. The active energy ray-curable pressure-sensitive adhesive composition is preferably an ultraviolet-curable type. The active energy ray-curable pressure-sensitive adhesive composition can further contain an active energy ray-polymerizable compound in addition to the base polymer and the cross-linking agent. Further, if necessary, it may contain at least one of a photopolymerization initiator or a photosensitizer.

The pressure-sensitive adhesive composition includes fine particles for imparting light scattering properties, beads (resin beads, glass beads, etc.), glass fibers, resins other than the base polymer, pressure-sensitive adhesives, fillers (metal powders, and other inorganic powders). Etc.), antioxidants, UV absorbers, dyes, pigments, colorants, antifoaming agents, corrosion inhibitors, photopolymerization initiators and other additives can be included.

The first pressure-sensitive adhesive layer 20 can be formed by applying an organic solvent diluted solution of the pressure-sensitive adhesive composition on a substrate and drying it. When the active energy ray-curable pressure-sensitive adhesive composition is used, a cured product having a desired degree of curing by irradiating the pressure-sensitive adhesive layer formed on the substrate with active energy rays (first pressure-sensitive adhesive layer 20). ).

The thickness of the first pressure-sensitive adhesive layer 20 is such that when the front plate 10 and the circularly polarizing plate 30 can be bonded to each other and the flexible laminate 100 is bent with the front plate 10 side inside, the front plate 10 is thickened. The thickness is not particularly limited as long as it can absorb the generated stress. The thickness of the first pressure-sensitive adhesive layer 20 is, for example, preferably 5 μm or more, more preferably 7 μm or more, further preferably 10 μm or more, and may be 20 μm or more. The thickness of the first pressure-sensitive adhesive layer 20 is usually 100 μm or less, preferably 90 μm or less, and more preferably 80 μm or less. Here, the "adhesive" as used herein is also referred to as a pressure-sensitive adhesive. On the other hand, in the present specification, the "adhesive" refers to an adhesive other than the pressure-sensitive adhesive (pressure-sensitive adhesive), and is clearly distinguished from the pressure-sensitive adhesive. The first pressure-sensitive adhesive layer 20 may be one layer or may be composed of two or more layers, but is preferably one layer.

The storage elastic modulus G'[MPa] of the first pressure-sensitive adhesive layer 20 may be, for example, 0.02 MPa or more, preferably 0.03 MPa or more under the conditions of a temperature of 25 ° C. and a relative humidity of 50% RH. More preferably, it is 0.05 MPa or more. On the other hand, the storage elastic modulus G'[MPa] is preferably 0.1 MPa or less, and more preferably 0.08 MPa or less under the conditions of a temperature of 25 ° C. and a relative humidity of 50% RH. When the storage elastic modulus G'is in the above range, the change in the thickness of the first pressure-sensitive adhesive layer 20 tends to be small even when the flexible laminate 100 is repeatedly bent. Further, the first pressure-sensitive adhesive layer 20 may be formed from a pressure-sensitive adhesive composition as a material for the third B pressure-sensitive adhesive layer, which will be described later, so as to have the same storage elastic modulus G'as that of the third B pressure-sensitive adhesive layer. The storage modulus of the first adhesive layer 20 is below the storage modulus G _A of the 3A adhesive layer described in the section of <Third adhesive layer>'and the 3B storage modulus of the pressure-sensitive adhesive layer G _B It can be measured according to the method of measuring'.

<Circular polarizing plate>
The circular polarizing plate 30 can include a linear polarizing plate 31 and a retardation layer 32. The linear polarizing plate 31 is arranged on the first pressure-sensitive adhesive layer 20 side, and the retardation layer 32 is placed on the second pressure-sensitive adhesive layer 40 side. Can be placed. The circularly polarizing plate 30 can convert light (external light) incident on the flexible laminated body 100 from the visible side (front plate 10 side) of the image display device including the flexible laminated body 100 into circularly polarized light. Further, since the circularly polarizing plate 30 can absorb the external light reflected by the display element in the image display device, the flexible laminated body 100 can be provided with a function as an antireflection film.

The thickness of the circularly polarizing plate 30 is preferably, for example, 100 μm or less, more preferably 50 μm or less, and may be 40 μm or less in order to improve the flexibility of the flexible laminated body 100. The thickness of the circularly polarizing plate 30 can be, for example, 10 μm or more.

(Linear polarizing plate)
The linear polarizing plate 31 has a function of selectively transmitting linearly polarized light in a certain direction from unpolarized light rays such as natural light. The linear polarizing plate 31 can include a stretched film on which a dichroic dye is adsorbed, a film on which the dichroic dye is applied and cured, or the like as a polarizer. The film obtained by applying and curing the dichroic dye is obtained by applying and curing a composition containing a dichroic dye having liquid crystal properties or a composition containing a dichroic dye and a polymerizable liquid crystal compound. A film having a layer or the like can be used. Specifically, iodine or a dichroic organic dye can be used as the dichroic dye. For dichroic organic dyes, C.I. I. Included are dichroic direct dyes made of disuazo compounds such as DIRECT RED 39 and dichroic direct dyes made of compounds such as trisazo and tetrakisazo. A film coated with a dichroic dye and cured is preferable because there is no limitation on the bending direction as compared with a stretched film on which a dichroic dye is adsorbed.

<Linear polarizing plate in which a stretched film on which a dichroic dye is adsorbed serves as a polarizer>
Hereinafter, a linear polarizing plate in which a stretched film on which a dichroic dye is adsorbed serves as a polarizer will be described. The stretched film on which the dichroic dye is adsorbed is usually a step of uniaxially stretching the polyvinyl alcohol-based resin film and a step of adsorbing the dichroic dye by dyeing the polyvinyl alcohol-based resin film with the dichroic dye. , And the step of treating the polyvinyl alcohol-based resin film on which the dichroic dye is adsorbed with an aqueous boric acid solution, and the step of washing the polyvinyl alcohol-based resin film on which the dichroic dye is adsorbed with water after the treatment with the boric acid aqueous solution. Manufactured by passing. The stretched film produced by the above step on which the dichroic dye is adsorbed may be used as it is as a linear polarizing plate, or may be used as a linear polarizing plate after a transparent protective film is attached to one or both sides thereof. .. The thickness of the polarizer (stretched film on which the dichroic dye is adsorbed) thus obtained is preferably 2 μm to 40 μm.

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 other monomers copolymerizable with vinyl acetate include unsaturated carboxylic acids, olefins, vinyl ethers, unsaturated sulfonic acids, and (meth) acrylamides having an ammonium group.

The saponification degree of the polyvinyl alcohol-based resin is usually about 85 to 100 mol%, preferably 98 mol% or more. The polyvinyl alcohol-based resin may be modified, and for example, polyvinyl formal, polyvinyl acetal, etc. modified with aldehydes can be used. The degree of polymerization of the polyvinyl alcohol-based resin is usually about 1000 to 10000, preferably in the range of 1500 to 5000.

By forming a film of such a polyvinyl alcohol-based resin, a raw film (that is, a polyvinyl alcohol-based resin film) used as a material for a polarizer can be obtained. The method for forming the 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 resin film can be, for example, about 10 μm to 150 μm.

The uniaxial stretching of the polyvinyl alcohol-based resin film can be performed before dyeing with a dichroic dye, at the same time as 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. Furthermore, it is also possible to perform uniaxial stretching in these a plurality of steps. In uniaxial stretching, rolls having different peripheral speeds may be uniaxially stretched, or thermal rolls may be used to uniaxially stretch the rolls. The uniaxial stretching may be a dry stretching in which the stretching is performed in the atmosphere, or a wet stretching in which the polyvinyl alcohol-based resin film is swollen using a solvent. The draw ratio is usually about 3 to 8 times.

The thickness of the linear polarizing plate provided with the stretched film as a polarizer may be, for example, 1 μm or more, 5 μm or more, or 7 μm or more. The thickness of the linear polarizing plate provided with the stretched film as a polarizer may be 100 μm or less, 50 μm or less, 30 μm or less, or 20 μm or less.

The material of the transparent protective film to be bonded to one side or both sides of the polarizer is not particularly limited, but is, for example, a cyclic polyolefin resin film, a cellulose acetate resin film made of a resin such as triacetyl cellulose or diacetyl cellulose, or polyethylene terephthalate. , Polyethylene naphthalate, polyester resin film made of resin such as polybutylene terephthalate, polycarbonate resin film, (meth) acrylic resin film, polypropylene resin film and other films known in the art. .. From the viewpoint of thinning, the thickness of the transparent protective film is usually 300 μm or less, preferably 200 μm or less, and more preferably 100 μm or less. The thickness of the transparent protective film is usually 5 μm or more, preferably 20 μm or more. The transparent protective film may or may not have a phase difference. Instead of the transparent protective film, an overcoat layer may be formed on one or both sides of the polarizer. The overcoat layer is obtained by applying an adhesive used as a bonding layer described later. The thickness of the overcoat layer is, for example, 10 μm or less, preferably 5 μm or less. The thickness of the overcoat layer is, for example, 0.01 μm or more, preferably 0.1 μm or more.

<A linear polarizing plate in which a film coated with a dichroic dye and cured becomes a polarizer>
Next, a linear polarizing plate in which a film coated with a dichroic dye and cured becomes a polarizer will be described. As the film to which the dichroic dye is applied and cured, the composition containing the dichroic dye having a liquid crystal property as described above or the composition containing the dichroic dye and the polymerizable liquid crystal compound is applied and cured. A film having a layer obtained by the above process (hereinafter, these are collectively referred to as "a film formed from a liquid crystal layer") or the like can be used. The film formed from the liquid crystal layer may be used as a linear polarizing plate by peeling off the base material or used as a linear polarizing plate together with the base material, or may be used as a linear polarizing plate after a transparent protective film is attached to one or both sides thereof. good. As the transparent protective film, the same material as the transparent protective film in which the above-mentioned stretched film is bonded to a linear polarizing plate serving as a polarizer can be used.

Specific examples of the film formed from the liquid crystal layer include the films described in JP2013-37353A, JP2013-33249, and the like.

The film formed from the liquid crystal layer is preferably thin, but if it is too thin, the strength tends to decrease and the processability tends to be inferior. 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. The thickness of the linear polarizing plate in which the film formed from the liquid crystal layer serves as a polarizer may be, for example, 1 μm or more and 50 μm or less, and may be 5 μm or more and 30 μm or less.

(Phase difference layer)
The retardation layer 32 may be one layer or two or more layers. The retardation layer 32 may have an overcoat layer that protects the surface thereof, a base film that supports the retardation layer, and the like. The retardation layer 32 includes a λ / 4 layer, and may further include at least one of a λ / 2 layer and a positive C layer. When the retardation layer 32 includes the λ / 2 layer, the λ / 2 layer and the λ / 4 layer are laminated in order from the linear polarizing plate 31 side. When the retardation layer 32 includes the positive C layer, the λ / 4 layer and the positive C layer may be laminated in order from the linear polarizing plate 31 side, and the positive C layer and the λ / 4 layer may be stacked in order from the linear polarizing plate 31 side. It may be laminated. The thickness of the retardation layer 32 is, for example, 0.1 μm or more and 10 μm or less, preferably 0.5 μm or more and 8 μm or less, and more preferably 1 μm or more and 6 μm or less.

The retardation layer 32 may be formed from the resin film exemplified as the material of the transparent protective film described above, or may be formed from a layer in which the polymerizable liquid crystal compound is cured. The retardation layer 32 may further include an alignment film and a base film, and is composed of an adhesive or an adhesive for bonding the λ / 4 layer, the λ / 2 layer, and the positive C layer. It may have a layer (hereinafter, also referred to as a "bonded layer").

When the retardation layer 32 is formed from a layer obtained by curing a polymerizable liquid crystal compound, the retardation layer 32 can be formed by applying a composition containing the polymerizable liquid crystal compound to a base film and curing it. An orientation layer may be formed between the base film and the coating layer. The material and thickness of the base film may be the same as the material and thickness of the resin film (the transparent protective film). When the retardation layer 32 is formed from a layer obtained by curing a polymerizable liquid crystal compound, the retardation layer 32 may be incorporated into the flexible laminate 100 in the form of having an alignment layer and a base film. Further, the retardation layer 32 can be bonded to the linear polarizing plate 31 via a bonding layer described later.

(Lated layer)
The laminating layer is a layer formed from a pressure-sensitive adhesive or an adhesive as described above. As the pressure-sensitive adhesive used as the material of the bonding layer, the same pressure-sensitive adhesive composition as those exemplified as the pressure-sensitive adhesive composition used as the material of the first pressure-sensitive adhesive layer 20 and the second pressure-sensitive adhesive layer 40 described later can be used. , Other adhesives, for example, (meth) acrylic adhesives, styrene adhesives, silicone adhesives, rubber adhesives, which are different from the materials of the first adhesive layer 20 and the second adhesive layer 40 described later. Urethane-based pressure-sensitive adhesives, polyester-based pressure-sensitive adhesives, epoxy-based copolymer pressure-sensitive adhesives, and the like can also be used.

As the adhesive used as the material of the bonding layer, for example, one or a combination of two or more of water-based adhesives, active energy ray-curable adhesives, and the like can be formed. Examples of the water-based adhesive include a polyvinyl alcohol-based resin aqueous solution, a water-based two-component urethane-based emulsion adhesive, and the like. The active energy ray-curable adhesive is an adhesive that cures by irradiating with active energy rays such as ultraviolet rays, and is, for example, an adhesive containing a polymerizable compound and a photopolymerizable initiator, and an adhesive containing a photoreactive resin. , Adhesives containing a binder resin and a photoreactive cross-linking agent, and the like. Examples of the polymerizable compound include photopolymerizable monomers such as a photocurable epoxy monomer, a photocurable acrylic monomer, and a photocurable urethane monomer, and oligomers derived from these monomers. Examples of the photopolymerization initiator include compounds containing substances that generate active species such as neutral radicals, anion radicals, and cationic radicals by irradiating them with active energy rays such as ultraviolet rays.

The thickness of the bonding layer is not particularly limited, but when the pressure-sensitive adhesive layer is used as the bonding layer, it is preferably 10 μm or more, 15 μm or more, 20 μm or more, or 25 μm or more. It may be 200 μm or less, 100 μm or less, or 50 μm or less. When an adhesive layer is used as the bonding layer, the thickness of the bonding layer is preferably 0.1 μm or more, may be 0.5 μm or more, is preferably 10 μm or less, and is 5 μm or less. There may be.

<Second adhesive layer>
The second pressure-sensitive adhesive layer 40 is a layer for bonding the circularly polarizing plate 30 and the TS layer 50, and can be formed by using the pressure-sensitive adhesive composition. The thickness of the second pressure-sensitive adhesive layer 40 is such that when the circularly polarizing plate 30 and the TS layer 50 can be bonded together and the image display device is bent with the front plate 10 side inside, the circularly polarizing plate 30 can be used. The thickness is not particularly limited as long as it can absorb the generated stress. The thickness of the second pressure-sensitive adhesive layer 40 is, for example, preferably 10 μm or more, more preferably 20 μm or more, further preferably 25 μm or more, and may be 30 μm or more. The thickness of the second pressure-sensitive adhesive layer 40 is usually 80 μm or less, preferably 70 μm or less, and more preferably 60 μm or less.

As the pressure-sensitive adhesive composition used as the material of the second pressure-sensitive adhesive layer 40, the same pressure-sensitive adhesive composition as that exemplified as the pressure-sensitive adhesive composition used as the material of the first pressure-sensitive adhesive layer 20 can be used. It is also possible to use a pressure-sensitive adhesive composition different from that exemplified as the pressure-sensitive adhesive composition used as the material of the pressure-sensitive adhesive layer 20. The method for forming the second pressure-sensitive adhesive layer 40 can also be the same as the method exemplified as the method for forming the first pressure-sensitive adhesive layer 20.

The storage elastic modulus G'[MPa] of the second pressure-sensitive adhesive layer 40 is relative to the temperature of 25 ° C. even when a pressure-sensitive adhesive composition different from the pressure-sensitive adhesive composition used as the material of the first pressure-sensitive adhesive layer 20 is used. Under the condition of humidity 50% RH, for example, it may be 0.02 MPa or more, preferably 0.03 MPa or more and 0.1 MPa or less, and more preferably 0.05 MPa or more and 0.08 MPa or less. As a result, the change in the thickness of the second pressure-sensitive adhesive layer 40 can be reduced even when the flexible laminate 100 is repeatedly bent. Further, the second pressure-sensitive adhesive layer 40 may be formed from a pressure-sensitive adhesive composition as a material for the third B pressure-sensitive adhesive layer 62, which will be described later, so as to have the same storage elastic modulus G'as that of the third B pressure-sensitive adhesive layer 62. .. The storage elastic modulus of the second pressure-sensitive adhesive layer 40 can be measured according to the measuring method described in the column of <third pressure-sensitive adhesive layer> described later.

<Touch sensor (TS) layer>
The touch sensor (TS) layer 50 may include at least a conductive layer having electrodes and wirings that make up the touch sensor. The conductive layer may include, for example, a patterned conductive layer formed in a pattern. When the TS layer 50 has two or more patterned conductive layers in the stacking direction, the conductive layers include all of these patterned conductive layers and are present between the patterned conductive layers arranged apart from each other in the stacking direction. It can include a via portion that electrically connects between the insulating layer and the patterned conductive layer. Further, the conductive layer has a boundary with an insulating layer existing between the patterned conductive layers arranged apart from each other in the stacking direction among the insulating layers in the space between the individual conductive portions included in the patterned conductive layer. It is also possible to include a part that is integrally provided so as not to be distinguished. The TS layer 50 may be composed of only the above-mentioned conductive layer, or may include a separation layer in addition to the above-mentioned conductive layer. Further, the TS layer 50 may include a base material that supports the conductive layer (hereinafter, also referred to as a “touch sensor base material”). The pattern conductive layer is preferably formed so as not to be visually recognized when the TS layer 50 is incorporated into the flexible laminate 100 and the image display device. The thickness of the TS layer 50 may be, for example, 5 μm or more and 100 μm or less, 5 μm or more and 50 μm or less, or 5 μm or more and 30 μm or less.

(Separation layer)
The TS layer 50 can include a separation layer as described above. In this case, the separation layer is formed on a substrate such as glass when the pattern conductive layer is formed, and is a layer located between the substrate and the pattern conductive layer. The separation layer is provided together with the pattern conductive layer to separate 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 the 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 pattern conductive layer and the separation layer separated from the substrate can be bonded to the third A pressure-sensitive adhesive layer 61, which will be described later, on the separation layer side.

(Protective layer)
The TS layer 50 may further include at least one protective layer in addition to or in place of the separating layer. The protective layer can be provided in contact with the patterned conductive layer to support the patterned conductive layer. Like the separation layer, the protective layer is also formed on a substrate such as glass when the pattern conductive layer is formed, and is a layer located between the substrate and the pattern conductive layer. The protective layer contains 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.

(Pattern conductive layer)
The pattern conductive layer may be a transparent conductive layer made of a metal oxide such as ITO, or may be a metal layer made of a metal such as aluminum, copper, silver, or gold. The pattern conductive layer functions as a sensor for detecting the touched position in the image display device. In this sensor, the detection method for detecting the touched position is not limited, and for example, a resistive film method, a capacitance coupling method, an optical sensor method, an ultrasonic method, an electromagnetic induction coupling method, and a surface acoustic wave. Any method selected from the group consisting of methods can be used. The sensor detection method included in the pattern conductive layer of the TS layer 50 is preferably a resistance film method or a capacitance coupling method because of its low cost.

The resistance film type TS layer 50 may be composed of, for example, an insulating spacer, a transparent conductive film provided as a resistance film in contact with the insulating spacer, and a touch position detection circuit. In the image display device provided with the TS layer 50, when the surface of the front plate 10 is touched, the opposing resistance films are short-circuited, so that a current flows through the resistance films. Next, the touch position detection circuit detects the touched position by detecting the change in voltage at this time.

The capacitance coupling type TS layer 50 may include, for example, a transparent electrode for position detection and a touch position detection circuit. In the image display device provided with the TS layer 50, when the surface of the front plate 10 is touched, the transparent electrode is grounded through the capacitance of the human body at the touched point. Next, the touch position detection circuit detects the touched position by detecting the grounding of the transparent electrode.

The TS layer 50 can be bonded to the second pressure-sensitive adhesive layer 40, for example, through a bonding layer or directly. When the TS layer 50 is bonded to the second pressure-sensitive adhesive layer 40 via the bonding layer, the bonding layer forms a bonding layer for bonding the linear polarizing plate 31 and the retardation layer 32. It can be formed by a pressure-sensitive adhesive or an adhesive using the same material.

(Touch sensor base material)
The TS layer 50 may include a touch sensor base material as described above. In this case, the touch sensor base material is preferably made of a material that is flexible and can transmit light. Specifically, the touch sensor base material is preferably a resin film or a resin film with a hard coat layer having a hard coat layer on at least one surface of the resin film. For example, the touch sensor base material can be a resin film that can transmit light. Further, examples of the light-transmissible resin film that can be used for the touch sensor base material include cyclic polyolefin-based resin film, triacetyl cellulose, cellulose acetate-based resin film made of a resin such as diacetyl cellulose, polyethylene terephthalate, and polyethylene. Examples of films known in the present technical field include polyester resin films made of resins such as naphthalate and polybutylene terephthalate, polycarbonate resin films, (meth) acrylic resin films, and polypropylene resin films. These resin films can be used alone or in combination of two or more.

The resin film with a hard coat layer forming the touch sensor base material may have a hard coat layer on one surface of a resin film capable of transmitting light, or may have a hard coat layer on both sides of the resin film. There may be. When the hard coat layers are provided on both sides of the resin film, the composition and thickness of each hard coat layer may be the same or different from each other. The resin film with a hard coat layer can impart impact resistance to the flexible laminate 100 as compared with a resin film having no hard coat layer. The hard coat layer of the resin film with the hard coat layer can be the same hard coat layer as the hard coat layer attached to the resin film which is the material of the front plate 10, and the hard coat layer different from the material of the front plate 10 can be used. You can also do it. The method of attaching the hard coat layer to the resin film can be the same as the method of attaching the hard coat layer to the front plate 10.

In recent years, image display devices have become thinner and lighter, and there is a tendency for members used in image display devices to be thinner and lighter. Therefore, the flexible laminate 100 is also required to be thin. When the flexible laminate 100 is made thinner, each layer (front plate 10, first adhesive layer 20, circular polarizing plate 30, second adhesive layer 40, TS layer 50, and third adhesive layer) forming the flexible laminate 100 is formed. It is required to reduce the thickness of 60). At this time, the TS layer 50 is required to have a strength to maintain normal electrical operation of the touch sensor by reducing the thickness of the TS layer 50 and ensuring resistance to the occurrence of cracks (flexibility). NS. In order to satisfy the above requirements, it is desirable to appropriately control, for example, the layer structure of the TS layer 50 and the layer structure of the third pressure-sensitive adhesive layer 60, which will be described later.

In the flexible laminate 100 of the present embodiment, the thickness of the TS layer 50 can be reduced by preferably forming the TS layer 50 so that the touch sensor base material is not included in the TS layer 50. Further, the layer structure of the third pressure-sensitive adhesive layer 60 has a structure including at least the third A pressure-sensitive adhesive layer 61 and the third B pressure-sensitive adhesive layer 62 as described later, and the third A pressure-sensitive adhesive layer 61 and the third B pressure-sensitive adhesive layer 62. Of these, the third A pressure-sensitive adhesive layer 61, which exhibits a larger storage elastic modulus, is in contact with the TS layer 50. As a result, bending resistance can be ensured, and the electrical operation of the TS layer 50 can be maintained normally. Therefore, the flexible laminate 100 of the present embodiment can realize excellent bending resistance (particularly, excellent inward bending flexibility) while reducing the thickness of the TS layer 50.

<Third adhesive layer>
The third pressure-sensitive adhesive layer 60 includes at least a third A pressure-sensitive adhesive layer 61 and a third B pressure-sensitive adhesive layer 62. The third A pressure-sensitive adhesive layer 61 is in contact with the TS layer 50 described above. The storage modulus of the 3A adhesive layer 61 G _A 'and the 3B storage modulus G _B of the adhesive layer 62' and fills the _{G A '/ G B' ≧} 1 relationship, and the 3A adhesive layer The thickness dA of 61 and the thickness dB of the third B pressure-sensitive adhesive layer 62 satisfy the relationship of dA / dB ≦ 1. The third pressure-sensitive adhesive layer 60 is a layer for bonding the TS layer 50 and the display laminate 70 described later, and has the characteristics (storage elastic modulus) of the above-mentioned third A pressure-sensitive adhesive layer 61 and the third B pressure-sensitive adhesive layer 62. G _a 'and G _B', and as long as it is configured to satisfy the thicknesses dA and dB), by a pressure-sensitive adhesive composition can be used to form the first adhesive layer 20 and the second pressure-sensitive adhesive layer 40 Can be formed.

Specifically, the pressure-sensitive adhesive composition used as the material for the third pressure-sensitive adhesive layer 60 is the same as that exemplified as the pressure-sensitive adhesive composition used as the material for the first pressure-sensitive adhesive layer 20 and the second pressure-sensitive adhesive layer 40. A pressure-sensitive adhesive composition can be used, and a pressure-sensitive adhesive composition different from that exemplified as the pressure-sensitive adhesive composition as a material for the first pressure-sensitive adhesive layer 20 and the second pressure-sensitive adhesive layer 40 can also be used. The method for forming the third pressure-sensitive adhesive layer 60 can also be the same as the method exemplified as the method for forming the first pressure-sensitive adhesive layer 20 and the second pressure-sensitive adhesive layer 40. The third pressure-sensitive adhesive layer 60 may be a pressure-sensitive adhesive layer composed of the third A pressure-sensitive adhesive layer 61 and the third B pressure-sensitive adhesive layer 62 as long as the third A pressure-sensitive adhesive layer 61 has a structure in contact with the TS layer 50. In addition to the third A pressure-sensitive adhesive layer 61 and the third B pressure-sensitive adhesive layer 62, the pressure-sensitive adhesive layer may further include one or more pressure-sensitive adhesive layers.

In the third adhesive layer 60, the storage elastic modulus of the 3A adhesive layer 61 G _A 'and the 3B storage modulus G _B of the adhesive layer 62' and, as described _{above, G A '/ G B'} ≧ Satisfy the relationship of 1. The storage modulus of the 3A adhesive layer 61 G _A 'and the 3B storage modulus G _B of the adhesive layer 62' and, it is preferable to satisfy the _{G A '/ G B'>} 1 relationship, G _A ' It is more preferable to satisfy the relationship of / G _B '≧ 2, it is more preferable to satisfy the relationship of G _A '/ G _B '≧ 5, and it is even more preferable to satisfy the relationship of G _A '/ G _B '≧ 10. preferable. The storage modulus of the 3A adhesive layer 61 G _A 'and the 3B storage modulus of the pressure-sensitive adhesive layer 62 G _B' and satisfy the relationship of the normal _{G A '/ G B' ≦} 50, G A '/ G it is preferable to satisfy the relationship of _B '≦ 30.

The 3A storage modulus G _A pressure-sensitive adhesive layer 61 'is preferably 0.1MPa or more. The 3A storage modulus G _A pressure-sensitive adhesive layer 61 'is more preferably not less than 0.25 MPa, further preferably 0.5MPa or more, even more preferably 1MPa or more. The 3A storage modulus G _A pressure-sensitive adhesive layer 61 'is preferably as is a large value, the storage modulus G _A are the pressure-sensitive adhesive layer' is usually not more than 10 MPa, 2.0 MPa or less Is preferable. On the other hand, the storage modulus of the 3B adhesive layer 62 G _B 'is the storage modulus G _A of the 3A adhesive layer 61' as long as it satisfies the G _A '/ G _B' ≧ 1 in relation to the, appropriate storage It can have an elastic modulus.

Storage modulus G _A of the 3A adhesive layer 61 ', and the storage modulus G _B of the 3B adhesive layer 62' may be obtained by the following measuring methods. First, a measurement sample (width 30 mm × length 30 mm) is prepared so that the thickness of each of the pressure-sensitive adhesive compositions used as the material of the third A pressure-sensitive adhesive layer 61 or the third B pressure-sensitive adhesive layer 62 is 150 μm. Next, the storage elastic modulus of the measurement sample is measured by using a rheometer (Anton Parr, MCR-301) under the conditions of a temperature of 25 ° C., a relative humidity of 50% RH, a stress of 1%, and a frequency of 1 Hz. Thereby obtaining a second 3A storage modulus G _A pressure-sensitive adhesive layer 61 ', and the storage modulus G _B of the 3B adhesive layer 62'.

Further, in the third pressure-sensitive adhesive layer 60, as described above, the thickness dA of the third A pressure-sensitive adhesive layer 61 and the thickness dB of the third B pressure-sensitive adhesive layer 62 satisfy the relationship of dA / dB ≦ 1. The thickness dA of the third A pressure-sensitive adhesive layer 61 and the thickness dB of the third B pressure-sensitive adhesive layer 62 preferably satisfy the relationship of dA / dB <1, and more preferably satisfy the relationship of dA / dB ≦ 0.7. , It is more preferable to satisfy the relationship of dA / dB ≦ 0.4, and even more preferably to satisfy the relationship of dA / dB ≦ 0.3. The thickness dA of the third A pressure-sensitive adhesive layer 61 and the thickness dB of the third B pressure-sensitive adhesive layer 62 usually satisfy the relationship of dA / dB ≧ 0.1, and preferably satisfy the relationship of dA / dB ≧ 0.2.

The thickness dA of the third A pressure-sensitive adhesive layer 61 is preferably 25 μm or less, more preferably 15 μm or less, and further preferably 10 μm or less. The thickness dA of the third A pressure-sensitive adhesive layer 61 is usually 1 μm or more, preferably 3 μm or more, and more preferably 5 μm or more. On the other hand, the thickness dB of the third B pressure-sensitive adhesive layer 62 can have an appropriate thickness as long as the relationship of dA / dB ≦ 1 is satisfied in relation to the thickness dA of the third A pressure-sensitive adhesive layer 61. From the viewpoint of enhancing the impact resistance of the third pressure-sensitive adhesive layer 60, the total thickness dA of the third A pressure-sensitive adhesive layer 61 and the thickness dB of the third B pressure-sensitive adhesive layer 62 is preferably 20 μm or more, preferably 30 μm or more. It is more preferable that the thickness is 40 μm or more. On the other hand, from the viewpoint of increasing the flexibility of the flexible laminated body 100, the total of the thickness dA of the third A pressure-sensitive adhesive layer 61 and the thickness dB of the third B pressure-sensitive adhesive layer 62 is preferably 100 μm or less, preferably 80 μm or less. Is more preferable.

The thickness dA of the third A pressure-sensitive adhesive layer 61 and the thickness dB of the third B pressure-sensitive adhesive layer 62 can be determined by the following measuring methods. That is, a cross section thereof is obtained by cutting the flexible laminate 100 or an image display device containing the flexible laminate 100 using a laser cutter, and the cross section is observed using a transmission electron microscope (SU8010, manufactured by HORIBA, Ltd.). From the observation image obtained thereby, the thickness dB of the third A pressure-sensitive adhesive layer 61 and the thickness dB of the third B pressure-sensitive adhesive layer 62 in the flexible laminate 100 or the image display device including the flexible laminate 100 can be obtained, respectively.

[Image display device]
FIG. 2 is a schematic cross-sectional view schematically showing an example of the image display device of the present embodiment. As shown in FIG. 2, the image display device 200 includes a flexible laminated body 100, and a back plate is laminated on the third adhesive layer 60 side. The back plate can be, for example, the display laminate 70. Specifically, the image display device 200 includes a flexible laminate 100 including a front plate 10 arranged on the viewing side, and a display laminate 70 including a display unit. The display laminate 70 is bonded to the flexible laminate 100 via the third pressure-sensitive adhesive layer 60. Such an image display device 200 can be a touch panel display device because the flexible laminated body 100 includes the TS layer 50.

The image display device 200 may be a flexible display panel. The image display device, which is a flexible display, may be configured to be foldable with the surface (visual side) of the front plate 10 inside, and the image display device may be wound with the surface (visual side) of the front plate 10 inside. It may be configured as possible.

The image display device 200 can be used as a mobile device such as a smartphone or tablet, a television, a digital photo frame, an electronic signboard, a measuring instrument, an instrument, an office device, a medical device, a computer device, or the like.

<Back plate>
As described above, the back plate can be, for example, the display laminate 70. The display laminate 70 can have a laminated structure including, for example, a display unit, an adhesive layer or a bonding layer, and a back film in this order. The pressure-sensitive adhesive layer is formed by using the same or different pressure-sensitive adhesive composition as those exemplified as the pressure-sensitive adhesive composition used as the material of the first pressure-sensitive adhesive layer 20, the second pressure-sensitive adhesive layer 40, and the third pressure-sensitive adhesive layer 60. can do. The bonding layer can be formed by using the same or different adhesive or adhesive as the pressure-sensitive adhesive or adhesive used as the material of the bonding layer described above. As the back film, for example, the same resin film as the material used for the front plate 10 described above or a resin film with a hard coat layer can be used. For example, as the back film, a resin film formed of a polymer such as polyimide, polyamide, or polyamideimide, which has excellent flexibility and can be configured to have high strength and high transparency, can be used.

Examples of the display unit included in the display laminate 70 include a display unit including a display element such as a liquid crystal display element, an organic EL display element, an inorganic EL display element, a plasma display element, and a field emission type display element.

The thickness of the back plate may be, for example, 5 μm or more and 2000 μm or less, preferably 10 μm or more and 1000 μm or less, and more preferably 15 μm or more and 500 μm or less.

[Manufacturing method of flexible laminate]
The flexible laminate 100 constitutes the flexible laminate 100 via a bonding layer, if necessary, in addition to the pressure-sensitive adhesive layer (first pressure-sensitive adhesive layer 20, second pressure-sensitive adhesive layer 40, and third pressure-sensitive adhesive layer 60). It can be manufactured by a method including a step of laminating the layers to be bonded to each other. When the layers are bonded to each other via the pressure-sensitive adhesive layer or the bonding layer, one or both of the bonding surfaces may be subjected to a surface activation treatment such as a corona treatment in order to improve the adhesion. preferable.

The circularly polarizing plate 30 can be manufactured by directly forming the linear polarizing plate 31 and the retardation layer 32 forming the same on the thermoplastic resin film or the base film as described above. The thermoplastic resin film or the base film may be incorporated into the flexible laminate 100, or may not be peeled off from the circularly polarizing plate 30 to become a component of the flexible laminate 100.

The TS layer 50 can be configured to include a patterned conductive layer, a separation layer and, if necessary, a protective layer. In this case, the TS layer 50 is formed by applying and curing a separation layer and a protective layer containing as necessary on a substrate such as glass as described above, and then a pattern conductive layer on the separation layer or the protective layer containing as necessary. Can be formed by vapor deposition. Further, in the TS layer 50, after the separation layer side is peeled off from the substrate, the third A pressure-sensitive adhesive layer 61 can be directly bonded to the separation layer side. On the other hand, the pattern conductive layer side of the TS layer 50 can be bonded to the second pressure-sensitive adhesive layer 40 via the bonding layer or directly.

Further, a pressure-sensitive adhesive layer having the same characteristics as the above-mentioned third A pressure-sensitive adhesive layer can be arranged on the pattern conductive layer side of the TS layer 50. The pressure-sensitive adhesive layer having the same characteristics as the third A pressure-sensitive adhesive layer has a storage elastic modulus larger than or the same as that of the second pressure-sensitive adhesive layer 40, and the thickness thereof is the second pressure-sensitive adhesive. It means an adhesive layer that is thinner or the same as the thickness of the layer 40.

Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited to these examples. For each sample described below, Sample 1 and Sample 2 represent examples, and Sample 3, Sample 4, and Sample 5 represent comparative examples.

<Measurement of the storage modulus G _A of 3A adhesive layer 'and the storage modulus of the 3B adhesive layer G _B'>
For each sample 'storage modulus and the 3B adhesive layer G _B' the 3A storage modulus G _A pressure-sensitive adhesive layer in the (image display device including a flexible laminate) is to be described later, it was determined by the measuring method described above .. Table 1 shows the storage elastic modulus G _{A'of the third A} pressure-sensitive adhesive layer and the storage elastic modulus G _B '(unit: MPa) of the third B pressure-sensitive adhesive layer in each sample.

<Measurement of thickness dA of the third A pressure-sensitive adhesive layer and thickness dB of the third B pressure-sensitive adhesive layer>
The thickness dA of the third A pressure-sensitive adhesive layer and the thickness dB of the third B pressure-sensitive adhesive layer in each sample described later were determined by the above-mentioned measuring methods. Table 1 shows the thickness dA of the third A pressure-sensitive adhesive layer and the thickness dB (unit: μm) of the third B pressure-sensitive adhesive layer in each sample.

<Flexibility test (inner bending flexibility test)>
For each sample to be described later, the bending resistance (inner bending bending resistance) when the front plate is repeatedly bent so as to be inside using a bending evaluation facility (STS-VRT-500 manufactured by Science Town) is determined. A test was conducted to evaluate. FIG. 3 is a diagram schematically showing the method of this test. As shown in FIG. 3, two individually movable mounting tables 501 and 502 are provided with a gap C (a distance at which the distance between the facing samples is 2.0 mm (1R) in the state of FIG. 3 (b)). The image display device was fixedly arranged so that the center of the image display device in the width direction was located at the center of the gap C and the front plate was located on the upper side (FIG. 3 (FIG. 3). a)). Further, as a bending operation, by rotating the positions P1 and P2 upward by 90 degrees with respect to the two mounting tables 501 and 502 with the center of the rotation axis as the center, the area of the image display device corresponding to the gap C of the mounting tables can be obtained. A bending force was applied (Fig. 3 (b)). After that, the two mounting tables 501 and 502 were returned to their original positions (FIG. 3 (a)). This series of bending operations was counted as one bending number. After repeating the bending operation at a temperature of 25 ° C., the number of bendings when a crack occurs in the region corresponding to the gap C of the TS layer in the image display device is recorded as the limit number of bendings, and is recorded as follows. evaluated. Table 1 shows the evaluation results. The moving speed of the mounting tables 501 and 502 and the pace at which the bending force was applied were the same in the tests for each sample. In Table 1, the limit number of bendings counted in each sample is also shown.
A: Even if the number of bends reached 200,000, the limit number of bends was not reached.
B: The limit number of bends was reached when the number of bends was 100,000 or more and less than 200,000.
C: The limit number of bends was reached when the number of bends was 10,000 or more and less than 100,000.
D: The limit number of bends was reached when the number of bends was less than 10,000.

[Manufacturing of flexible laminates and image display devices]
<Sample 1>
(Preparation of front plate)
As a front plate, a resin film with a hard coat layer having a thickness of 50 μm in which a hard coat layer was formed on one side of the resin film was prepared. The resin film is a transparent base film (thickness 40 μm, polyamide-imide film) prepared according to Example 4 of JP-A-2018-119141. A hard coat layer having a thickness of 10 μm is formed by coating one side of the transparent base film (the side to be the visual side in an image display device) with the following composition for a hard coat layer, and then drying the solvent and curing it with UV. bottom. As a result, a front plate (thickness 50 μm) was prepared.

Composition for forming a hard coat layer: 30 parts by mass of multifunctional acrylate (MIWON Specialty Chemical, MIRAMER M340), 50 parts by mass of nanosilica sol (particle size 12 nm, solid content 40%) dispersed in propylene glycol monomethyl ether, ethyl acetate 17 A part by mass, 2.7 parts by mass of a photopolymerization initiator (BASF, I184), and 0.3 parts by mass of a fluorine-based additive (Shinetsu Chemical Industry Co., Ltd., KY1203) are blended using a stirrer to mix polypropylene (PP). Manufactured by filtering with a filter of material.

(Preparation of the first adhesive layer)
An acrylic pressure-sensitive adhesive composition was applied onto the release film and dried to form a first pressure-sensitive adhesive layer, thereby preparing a first pressure-sensitive adhesive layer with a release film. The thickness of the first pressure-sensitive adhesive layer was 25 μm. The first pressure-sensitive adhesive layer with the release film was obtained by the following procedure.

First, in a reaction vessel equipped with a cooling tube, a nitrogen introduction tube, a thermometer and a stirrer, 80 parts by mass of ethyl acetate (solvent), 70 parts by mass of butyl acrylate, 20 parts by mass of methyl acrylate and 1.0 part by mass of acrylate. The mixed solution was charged, and the internal temperature was raised to 55 ° C. while replacing the air in the container with nitrogen gas to make it oxygen-free. Then, a total amount of a solution prepared by dissolving 0.2 parts by mass of the radical polymerization initiator (2,2'-azobisisobutyronitrile) in 10 parts by mass of ethyl acetate was added to the above mixed solution. While continuously adding ethyl acetate into the reaction vessel at an addition rate of 17.3 parts by mass / hr so that the concentration of the acrylic resin excluding the monomer becomes 35% by mass 1 hour after the addition of the polymerization initiator. The temperature was kept at an internal temperature of 54 to 56 ° C. for 12 hours, and finally ethyl acetate was added to adjust the concentration of the acrylic resin to 20% by mass. The obtained acrylic resin had a polystyrene-equivalent weight average molecular weight Mw of 1500,000 and Mw / Mn of 5.0 by GPC.

To 100 parts by mass of the acrylic resin obtained in the above step (solid content conversion value; the same applies hereinafter), 0.3 parts by mass of a thermal cross-linking agent (manufactured by Tosoh Corporation, product name "Coronate L") and a silane coupling agent ( Shin-Etsu Chemical Co., Ltd., product name "X-12-981") 0.5 parts by mass is mixed, and ethyl acetate is added so that the total solid content concentration becomes 10% by mass. A coating solution of the composition was obtained. Further, on the release-treated surface of the polyethylene terephthalate film (first release film, thickness 38 μm) that has been released from the coating solution of the above-mentioned acrylic pressure-sensitive adhesive composition, the thickness after drying using an applicator is set to 25 μm. Was applied to. The coating layer was dried at 100 ° C. for 1 minute to obtain a film having an adhesive layer. Then, another polyethylene terephthalate film (second release film, thickness 38 μm) that had been released from the mold was attached onto the exposed surface of the pressure-sensitive adhesive layer. Then, it was cured for 7 days under the conditions of a temperature of 23 ° C. and a relative humidity of 50% RH. As a result, an adhesive sheet (first adhesive layer with a release film) composed of a second release film / first adhesive layer / first release film was produced. The storage elastic modulus of the first pressure-sensitive adhesive layer at 25 ° C. and 50% RH relative humidity was 0.047 MPa. The storage elastic modulus G'of the first pressure-sensitive adhesive layer was determined by the same method as the method for measuring the storage elastic modulus described above. As will be described later, the acrylic pressure-sensitive adhesive composition used as the material for the first pressure-sensitive adhesive layer and the acrylic pressure-sensitive adhesive composition used as the material for the third B pressure-sensitive adhesive layer are the same.

(Preparation of circularly polarizing plate)
A circularly polarizing plate was prepared by the following procedure.

<Preparation of linear polarizing plate>
A polyvinyl alcohol (PVA) film having an average degree of polymerization of about 2400, a saponification degree of 99.9 mol% or more, and a thickness of 20 μm was prepared. After immersing the PVA film in pure water at 30 ° C, it was immersed in an aqueous solution having a mass ratio of iodine / potassium iodide / water of 0.02 / 2/100 at 30 ° C to perform iodine dyeing (iodine dyeing step). .. The PVA film that had undergone the iodine dyeing step was immersed in an aqueous solution having a mass ratio of potassium iodide / boric acid / water of 12/5/100 at 56.5 ° C. to perform boric acid treatment (boric acid treatment step). .. The PVA film that had undergone the boric acid treatment step was washed with pure water at 8 ° C. and then dried at 65 ° C. to obtain a polarizer in which iodine was adsorbed and oriented on polyvinyl alcohol. The PVA film was stretched in the iodine dyeing step and the boric acid treatment step. The total draw ratio of the PVA film was 5.3 times. The thickness of the obtained polarizer was 7 μm.

A nip roll of the polarizer obtained above and a cycloolefin polymer (COP) film (ZF-14, manufactured by Nippon Zeon Corporation, having an in-plane retardation value of 1 nm at a wavelength of 550 nm) having a thickness of 13 μm via an aqueous adhesive. I pasted them together. While maintaining the tension of the obtained laminate at 430 N / m, it was dried at 60 ° C. for 2 minutes to obtain a linear polarizing plate having a COP film on one side. The water-based adhesive is 100 parts of water, 3 parts of carboxyl group-modified polyvinyl alcohol ("Kuraray Poval KL318", manufactured by Kuraray Co., Ltd.), and water-soluble polyamide epoxy resin ("Smiley's resin 650" (solid content concentration 30%). (Aqueous solution) and 1.5 parts (manufactured by Taoka Chemical Industry Co., Ltd.) were added to prepare.

<Preparation of retardation layer and fabrication of circularly polarizing plate>
The polarizer side of the linear polarizing plate and the retardation layer were laminated via an acrylic pressure-sensitive adhesive layer having a thickness of 5 μm. The retardation layer has a thickness of 5 μm, and the layer structure includes a λ / 2 layer (thickness 2 μm) including a layer obtained by curing the liquid crystal compound / a UV curable adhesive layer (thickness 2 μm) / a layer obtained by curing the liquid crystal compound. It was a λ / 4 layer (thickness 1 μm). In this way, a circularly polarizing plate (thickness 30 μm, layer structure: COP film / polarizer / retardation layer) was produced.

(Preparation of the second adhesive layer)
The same pressure-sensitive adhesive composition as the acrylic pressure-sensitive adhesive composition on which the first pressure-sensitive adhesive layer is formed is applied onto the release film and dried to form a second pressure-sensitive adhesive layer, thereby forming a second pressure-sensitive adhesive with a release film. A layer (an adhesive sheet composed of a second release film / a second adhesive layer / a first release film) was prepared. The thickness of the second pressure-sensitive adhesive layer was 25 μm. The storage elastic modulus G'of the second pressure-sensitive adhesive layer is the same as that of the first pressure-sensitive adhesive layer.

(Preparation of TS layer)
First, a separation layer was formed on the glass plate by coating the glass plate with an acrylic resin. Next, a first pattern electrode layer having a predetermined pattern, wiring, a first insulating layer, a second pattern electrode layer having a bridge-like pattern connecting the patterns of the first pattern electrode layer, and a second insulating layer are placed on the separation layer. It was formed in this order to prepare a touch sensor layer including a separation layer. The thickness of this touch sensor layer was 8 μm.

The first pattern electrode layer, the second pattern electrode layer, and the wiring were manufactured as follows. First, a translucent electrode film or a metal film was formed by a known sputtering method, and then a photoresist film pattern was formed on the translucent electrode film or the metal film by a known photolithography method. Further, after patterning the translucent electrode film or the metal film by a known etching method, the photoresist film pattern was removed. Here, the translucent electrode film was deposited by a sputtering method in the order of an ITO film (thickness 450 Å), an APC film (thickness 110 Å), and an ITO film (thickness 450 Å) at an oxygen flow rate of 0 sccm. The first insulating layer and the second insulating layer were patterned by a known photolithography method using a composition for forming an insulating layer.

Next, a peelable resin film was laminated on the second insulating layer, and the touch sensor layer including the separation layer was separated from the glass plate. From the above, the TS layer was prepared.

(Preparation of third adhesive layer)
<Preparation of 3A adhesive layer>
The acrylic pressure-sensitive adhesive composition was applied onto the release film and dried to form a third A pressure-sensitive adhesive layer, thereby preparing a third A pressure-sensitive adhesive layer with a release film. The thickness of the third A pressure-sensitive adhesive layer was 15 μm. The third A pressure-sensitive adhesive layer with the release film was obtained by the following procedure.

81.8 parts by mass of acetone (solvent), 78.6 parts by mass of butyl acrylate, 0.4 parts by mass of acrylic acid, 20 parts by mass of methyl methacrylate in a reaction vessel equipped with a cooling tube, a nitrogen introduction tube, a thermometer and a stirrer. A mixed solution of 1.0 part by mass of 2-hydroxyethyl acrylate was charged, and the internal temperature was raised to 55 ° C. while replacing the air in the container with nitrogen gas to make it oxygen-free. Then, a total amount of a solution prepared by dissolving 0.14 parts by mass of azobisisobutyronitrile (polymerization initiator) in 10 parts by mass of acetone was added. Acetone was continuously added into the reaction vessel at an addition rate of 17.3 parts by mass / hr so that the concentration of the acrylic resin excluding the monomer was 35% by mass 1 hour after the addition of the polymerization initiator. The temperature was kept at 54 to 56 ° C. for 12 hours, and finally acetone was added to adjust the concentration of the acrylic resin to 20% by mass. The obtained acrylic resin had a polystyrene-equivalent weight average molecular weight Mw of 1500,000 and Mw / Mn of 5.0 by GPC.

To 100 parts by mass of the acrylic resin obtained in the above step (solid content conversion value; the same applies hereinafter), 0.3 parts by mass of a thermal cross-linking agent (manufactured by Tosoh Corporation, product name "Coronate L") and a silane coupling agent ( Application of the acrylic pressure-sensitive adhesive composition by mixing 0.5 parts by mass of Shin-Etsu Chemical Co., Ltd., product name "KBM403") and adding ethyl acetate so that the total solid content concentration is 10% by mass. A solution was obtained. Further, the release-treated surface of the polyethylene terephthalate film (first release film, thickness 38 μm) that has been released from the coating solution of the above-mentioned acrylic pressure-sensitive adhesive composition is dried using an applicator so that the thickness becomes 15 μm. Was applied to. The coating layer was dried at 100 ° C. for 1 minute to obtain a film having an adhesive layer. Then, another polyethylene terephthalate film (second release film, thickness 38 μm) that had been released from the mold was attached onto the exposed surface of the pressure-sensitive adhesive layer. Then, it was cured for 7 days under the conditions of a temperature of 23 ° C. and a relative humidity of 50% RH. As a result, an adhesive sheet (third A pressure-sensitive adhesive layer with a release film) composed of a second release film / a third A pressure-sensitive adhesive layer / a first release film was produced. The storage elastic modulus of the third A pressure-sensitive adhesive layer at 25 ° C. and a relative humidity of 50% RH was 0.27 MPa.

<Preparation of 3B adhesive layer>
The same pressure-sensitive adhesive composition as the acrylic pressure-sensitive adhesive composition on which the first pressure-sensitive adhesive layer is formed is applied onto the release film and dried to form a third B pressure-sensitive adhesive layer, thereby forming a third-B pressure-sensitive adhesive with a release film. A layer (adhesive sheet composed of a second release film / a third B pressure-sensitive adhesive layer / a first release film) was prepared. The thickness of the third B pressure-sensitive adhesive layer was 35 μm.

<Preparation of third adhesive layer>
One surface of the 3A pressure-sensitive adhesive layer exposed by peeling off the first release film of the third A pressure-sensitive adhesive layer with the release film, and the second release film of the third B pressure-sensitive adhesive layer with the release film are peeled off and exposed. The other surface of the 3B pressure-sensitive adhesive layer was subjected to corona treatment, and the corona-treated surfaces were bonded to each other. As a result, an adhesive sheet (third adhesive layer with a release film) composed of a second release film / a third A pressure-sensitive adhesive layer / a third B pressure-sensitive adhesive layer / a first release film was produced. From the above, the third pressure-sensitive adhesive layer was prepared.

(Preparation of display laminate)
A resin molded body was formed from the polyimide-based resin composition, and this was prepared as a simulated molded body of the display laminate. This simulated molded product had a thickness of 95 μm.

(Manufacturing of a flexible laminate and an image display device including the flexible laminate)
An image display device was produced by laminating each of the above-mentioned members using a conventionally known method. This image display device includes a front plate 10, a first pressure-sensitive adhesive layer 20, a circularly polarizing plate 30, a second pressure-sensitive adhesive layer 40, a TS layer 50, a third pressure-sensitive adhesive layer 60, and a display laminate 70 in this order. The total thickness was 283 μm. The dimensions of the image display device were 177 mm in length × 105 mm in width. In producing the above image display device, when the members were bonded, the bonded surface was subjected to corona treatment. Regarding the first pressure-sensitive adhesive layer, the first release film and the second release film were appropriately peeled off, and laminated so as to be in contact with the resin film of the front plate and the COP film of the circularly polarizing plate. Regarding the second pressure-sensitive adhesive layer, the first release film and the second release film were appropriately peeled off and laminated so as to be in contact with the retardation layer of the circularly polarizing plate and the second insulating layer of the touch sensor layer. Regarding the third pressure-sensitive adhesive layer, the first release film and the second release film are appropriately peeled off, the third A pressure-sensitive adhesive layer is in contact with the separation layer of the touch sensor layer, and the third B pressure-sensitive adhesive layer is in contact with the display laminate. Laminated in.

[Sample 2]
An image display device for Sample 2 was obtained by the same procedure as for Sample 1, except that the third A pressure-sensitive adhesive layer and the third B pressure-sensitive adhesive layer having the storage elastic modulus and thickness shown in Table 1 were replaced.

Here, the third A pressure-sensitive adhesive layer of sample 2 is prepared as a third A pressure-sensitive adhesive layer with a release film by applying an acrylic pressure-sensitive adhesive composition on a release film and drying the same as in sample 1. However, the third A pressure-sensitive adhesive layer with the release film of Sample 2 was obtained by the following procedure. The thickness of the third A pressure-sensitive adhesive layer of Sample 2 was 10 μm.

In a reaction vessel equipped with a cooling tube, a nitrogen introduction tube, a thermometer and a stirrer, 80 parts by mass of methyl ethyl ketone (solvent), 45 parts by mass of n-butyl acrylate, 45 parts by mass of 2-ethylhexyl acrylate, 4-hydroxybutyl acrylate. A mixed solution of 10 parts by mass was charged, and the internal temperature was raised to 55 ° C. while replacing the air in the container with nitrogen gas to make it oxygen-free. Then, a total amount of a solution prepared by dissolving 0.14 parts by mass of azobisisobutyronitrile (polymerization initiator) in 10 parts by mass of methyl ethyl ketone was added. While continuously adding methyl ethyl ketone into the reaction vessel at an addition rate of 17.3 parts by mass / hr so that the concentration of the acrylic resin excluding the monomer becomes 35% by mass 1 hour after the addition of the polymerization initiator. The temperature was kept at 54 to 56 ° C. for 12 hours, and finally acetone was added to adjust the concentration of the acrylic resin to 20% by mass. The obtained acrylic resin had a polystyrene-equivalent weight average molecular weight Mw of 1520000 and Mw / Mn of 4.4 by GPC.

To 100 parts by mass of acrylic resin obtained in the above step (solid content conversion value; the same applies hereinafter), 1.0 part by mass of a thermal cross-linking agent (manufactured by Shin-Etsu Chemical Co., Ltd., product name "TD-75") and silane coupling. The acrylic pressure-sensitive adhesive composition is prepared by mixing 0.2 parts by mass of an agent (manufactured by Shin-Etsu Chemical Co., Ltd., product name "KBM403") and adding methyl ethyl ketone so that the total solid content concentration is 10% by mass. A coating solution was obtained. Further, on the release-treated surface of the polyethylene terephthalate film (first release film, thickness 38 μm) that has been released from the coating solution of the above-mentioned acrylic pressure-sensitive adhesive composition, the thickness after drying using an applicator is set to 10 μm. Was applied to. The coating layer was dried at 90 ° C. for 1 minute to obtain a film having an adhesive layer. Then, another polyethylene terephthalate film (second release film, thickness 38 μm) that had been released from the mold was attached onto the exposed surface of the pressure-sensitive adhesive layer. Then, it was cured for 7 days under the conditions of a temperature of 23 ° C. and a relative humidity of 50% RH. As a result, an adhesive sheet (third A pressure-sensitive adhesive layer with a release film) composed of a second release film / a third A pressure-sensitive adhesive layer / a first release film was produced. The storage elastic modulus of the third A pressure-sensitive adhesive layer at 25 ° C. and a relative humidity of 50% RH was 1.12 MPa.

[Sample 3 to Sample 5]
An image display device for Samples 3 to 5 was obtained by the same procedure as that for Sample 1, except that the third A pressure-sensitive adhesive layer and the third B pressure-sensitive adhesive layer having the storage elastic modulus and thickness shown in Table 1 were replaced.

Specifically, the sample 3 has a structure in which the flexible laminate does not include the third B pressure-sensitive adhesive layer. That is, as the third pressure-sensitive adhesive layer of sample 3, the pressure-sensitive adhesive composition (coating solution of the acrylic pressure-sensitive adhesive composition) on which the third-A pressure-sensitive adhesive layer was formed in sample 2 is used, and the third-A pressure-sensitive adhesive having a thickness of 50 μm is used. Only layers were formed.

Further, for Sample 4, the pressure-sensitive adhesive composition (coating solution of the acrylic pressure-sensitive adhesive composition) on which the third B pressure-sensitive adhesive layer was formed in Sample 1 and Sample 2 was used to form a third A pressure-sensitive adhesive layer having a thickness of 10 μm. .. Further, for Sample 4, the pressure-sensitive adhesive composition (coating solution of the acrylic pressure-sensitive adhesive composition) on which the third A pressure-sensitive adhesive layer was formed in Sample 2 was used to form a third B pressure-sensitive adhesive layer having a thickness of 40 μm.

Further, in Sample 5, the third A pressure-sensitive adhesive layer was formed by using the pressure-sensitive adhesive composition (coating solution of the acrylic pressure-sensitive adhesive composition) on which the third A pressure-sensitive adhesive layer was formed in Sample 2, and the thickness thereof was set to 40 μm. .. Further, in Sample 5, the third B pressure-sensitive adhesive layer was formed by using the pressure-sensitive adhesive composition (coating solution of the acrylic pressure-sensitive adhesive composition) on which the third B pressure-sensitive adhesive layer was formed in Sample 1 and Sample 2. It was set to 10 μm.

[Discussion]
The above-mentioned flexibility test (inner bending flexibility test) was performed on Samples 1 to 5. The results are shown in Table 1. Samples 1 to 2 are examples, and samples 3 to 5 are comparative examples. According to Table 1, Samples 1 to 2 of Examples were excellent in bending resistance (internal bending and bending resistance).

10 Front plate, 20 1st adhesive layer, 30 circular polarizing plate, 31 linear polarizing plate, 32 retardation layer, 40 2nd adhesive layer, 50 touch sensor (TS) layer, 60 3rd adhesive layer, 61st 3A Adhesive Layer, 62 3B Adhesive Layer, 70 Display Laminate, 100 Flexible Laminate, 200 Image Display.

Claims (5)

A flexible laminate including a front plate, a first pressure-sensitive adhesive layer, a circularly polarizing plate, a second pressure-sensitive adhesive layer, a touch sensor layer, and a third pressure-sensitive adhesive layer in this order.
The third pressure-sensitive adhesive layer includes at least a third A pressure-sensitive adhesive layer and a third B pressure-sensitive adhesive layer.
The third A adhesive layer is in contact with the touch sensor layer, and is in contact with the touch sensor layer.
The 'storage modulus of the first 3B adhesive layer G _B' the 3A adhesive layer storage modulus G _A and satisfies G _A '/ G _B' ≧ 1 relationship,
A flexible laminate in which the thickness dA of the third A pressure-sensitive adhesive layer and the thickness dB of the third B pressure-sensitive adhesive layer satisfy the relationship of dA / dB ≦ 1. Wherein said 3A adhesive layer storage modulus G _A of the 'is 0.1MPa or more, the flexible laminate of claim 1. The flexible laminate according to claim 1 or 2, wherein the thickness dA of the third A pressure-sensitive adhesive layer is 25 μm or less. The flexible laminate according to any one of claims 1 to 3 is provided.
An image display device in which a back plate is arranged on the third pressure-sensitive adhesive layer side. The image display device according to claim 4, wherein the image display device has a limit bending number of 200,000 times or more in a flexibility test in which the front plate is bent so as to be inside.

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