Laminate and display device

Abstract

The present invention addresses the problem of providing a laminate and a display device which each have both light resistance and impact resistance.　A laminate according to the present invention comprises resin layers, cured layers, and an adhesive layer, said laminate being characterized in that: a first cured layer, a first resin layer, a first adhesive layer, a second cured layer, and a second resin layer are laminated in this order; the first resin layer contains a dye compound that has a maximum absorption wavelength in the range of 360-379 nm in an ultraviolet visible light absorption spectrum of a wavelength region of 300-460 nm; the average light transmittance of the first resin layer in the wavelength region of 450-800 nm is not less than 87%; the storage modulus of the first resin layer is in the range of 4.0-8.0 GPa at 25°C; and the value of the ratio of the storage modulus of the second resin layer to the storage modulus of the first resin layer is in the range of 0.7-1.5 at 25°C.

Description

Laminate and display device

[0001] The present invention relates to a laminate and a display device, and more particularly to a laminate and a display device that have both light resistance and impact resistance.

[0002] Recently, there has been active development of flexible displays that can be folded or rolled up. Flexible displays consist of a display component and a cover component for protecting the display component.

[0003] In flexible displays, the substrate used in the cover member must be flexible. Therefore, consideration has been given to changing from the conventionally used glass substrate to a resin substrate or thinning the glass substrate itself. Among these, thin-film glass (Ultra Thin Glass: "UTG") has become mainstream as a substrate from the viewpoint of providing a luxurious feel and being less prone to creases (durability). However, since thin-film glass is vulnerable to impact and easily breaks, a technique is known in which a protective film is attached to the thin-film glass to improve its impact resistance when used as a cover member.

[0004] Patent Document 1 discloses a technique for improving the impact resistance of a cover member, in which a laminate in which a cured layer is laminated on a protective film is used as a cover member. However, the demand for impact resistance is increasing, and there is room for improvement.

[0005] There is also a technique for increasing the thickness of a laminate used as a cover member in order to improve impact resistance. However, increasing the thickness of the laminate reduces the flexibility of the laminate, making it difficult to achieve both impact resistance and flexibility in the laminate. Furthermore, this technique goes against the trend toward thinner flexible displays.

[0006] On the other hand, since many flexible displays are used in mobile devices, they are required to be durable for outdoor use, especially light resistance.

[0007] Patent Document 2 discloses a technology for achieving both light resistance and impact resistance in a display device, in which a pressure-sensitive adhesive layer containing a (meth)acrylic polymer of a specific composition and an ultraviolet absorber is used as a cover member.

[0008] Furthermore, Patent Document 3 discloses a technology for improving the light resistance of a display device, in which a highly transparent optical film having excellent blocking properties for ultraviolet light and the short wavelength region of visible light is used as a cover member. However, the demand for impact resistance is increasing, and there is room for improvement in achieving both light resistance and impact resistance.

[0009] Korean Patent Publication No. 10-2020-0072643 Japanese Patent Application Laid-Open No. 2020-139108 Japanese Patent Application Laid-Open No. 2017-187619

[0010] The present invention has been made in view of the above problems and circumstances, and an object of the present invention is to provide a laminate and a display device that have both light resistance and impact resistance.

[0011] In order to solve the above problems, the present inventors have investigated the causes of the above problems and have found that in a laminate having a resin layer, a cured layer, and an adhesive layer, the resin layer contains a dye compound having ultraviolet absorbing ability, and the light transmittance in the visible light region of the resin layer is each within a specific range, and the storage modulus of the resin layer is also within a specific range, thereby achieving both light resistance and impact resistance, and have arrived at the present invention. That is, the above problems according to the present invention are solved by the following means.

[0012] 1. A laminate having a resin layer, a cured layer, and an adhesive layer, wherein the layers are laminated in the following order: a first cured layer, a first resin layer, a first adhesive layer, a second cured layer, and a second resin layer; the first resin layer contains a dye compound whose maximum absorption wavelength is in the range of 360 to 379 nm in an ultraviolet-visible light absorption spectrum in a wavelength range of 300 to 460 nm; the first resin layer has an average light transmittance of 87% or more in a wavelength range of 450 to 800 nm; the first resin layer has a storage modulus at 25°C in the range of 4.0 to 8.0 GPa; and the ratio of the storage modulus at 25°C of the second resin layer to that of the first resin layer is in the range of 0.7 to 1.5.

[0013] 2. The laminate according to item 1, wherein the first resin layer contains a cellulose ester.

[0014] 3. The laminate according to item 1, wherein the dye compound has a structure represented by the following general formula (1):

[0015]

[0016] (In the formula, R １１ represents a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group, a hydroxy group, an amino group, an alkyl-substituted amino group, a carboxy group, an alkyloxycarbonyl group, a hydroxyalkyl group, an alkylcarbonyloxyalkyl group, a carboxyalkyl group, an alkyloxycarbonylalkyl group, an aryl group, an acyl group, or a sulfo group. １２ represents a hydrogen atom or a hydroxy group.

[0017] 4. The laminate according to item 1, wherein the dye compound has a structure represented by the following general formula (2):

[0018]

[0019] (In the formula, R ２１ represents a hydrogen atom or a hydroxy group. ２２ , R ２３ , and R ２４ represents an alkyl group, an alkoxy group, an alkyl-substituted amino group, a carboxy group, an alkyloxycarbonyl group, a hydroxyalkyl group, an alkylcarbonyloxyalkyl group, a carboxyalkyl group, an alkyloxycarbonylalkyl group, an aryl group, an acyl group, or a sulfo group.

[0020] 5. The laminate according to item 1, wherein the thickness of the first resin layer is within the range of 15 to 50 μm.

[0021] 6. The laminate according to item 1, wherein the second resin layer has a storage modulus at 25° C. in the range of 4.0 to 8.0 GPa.

[0022] 7. The laminate according to any one of items 1 to 6, further comprising a glass layer, wherein the first cured layer, the first resin layer, the first adhesive layer, the second cured layer, the second resin layer, and the glass layer are laminated in this order.

[0023] 8. The laminate according to item 7, further comprising a second adhesive layer, wherein the first cured layer, the first resin layer, the first adhesive layer, the second cured layer, the second resin layer, the second adhesive layer, and the glass layer are laminated in this order.

[0024] 9. The laminate according to item 7, wherein the thickness of the glass layer is within the range of 10 to 30 μm.

[0025] 10. The laminate according to item 8, further comprising a third adhesive layer, wherein the first cured layer, the first resin layer, the first adhesive layer, the second cured layer, the second resin layer, the second adhesive layer, the glass layer, and the third adhesive layer are laminated in this order.

[0026] 11. A display device comprising the laminate according to claim 10.

[0027] 12. The display device according to item 11, wherein the first resin layer of the laminate is disposed closer to the viewing side of the display device than the second resin layer.

[0028] According to the above-described means of the present invention, it is possible to provide a laminate and a display device that have both light resistance and impact resistance.

[0029] The mechanism by which the effects of the present invention are manifested or the mechanism of action is not clear, but is speculated as follows.

[0030] When thin film glass is used as the cover member, the cover member preferably has a member that protects the thin film glass. As described above, when a cover member including thin film glass and a member that protects the thin film glass is attached to a display device, the display device is required to have both light resistance and impact resistance. In addition, in view of the increasing demand for thinner display devices, the member that protects the thin film glass is required to be flexible and thin.

[0031] The laminate of the present invention, which is a member for protecting thin glass, i.e., a glass protective film, is laminated in the order of a first cured layer, a first resin layer, a first adhesive layer, a second cured layer, and a second resin layer. By having the cured layer in the laminate, the impact resistance of the display device when the laminate is attached can be improved. Furthermore, by dividing the cured layer into two layers, it is thought that the impact resistance of the display device when the laminate is attached can be maintained while also improving flexibility.

[0032] Furthermore, it is believed that the laminate having a resin layer can improve the light resistance and flexibility of the display device when the laminate is attached.

[0033] Specifically, the first resin layer contains a dye compound whose maximum absorption wavelength is in the range of 360 to 379 nm in the absorption spectrum of the wavelength region of 300 to 460 nm. In other words, the first resin layer is endowed with the property of absorbing ultraviolet light. This protects the display device from ultraviolet light and improves the light resistance of the display device when the laminate is attached.

[0034] The first resin layer has an average light transmittance of 87% or more in the wavelength range of 450 to 800 nm, i.e., the first resin layer is endowed with the property of transmitting visible light. This makes it possible to suppress absorption by the resin layer of light emitted from the light-emitting element or light-emitting device in the display device, thereby increasing the amount of light that can be seen. In other words, it is possible to reduce light emission loss.

[0035] Furthermore, by setting the storage modulus of the first resin layer within a specific range, i.e., by disposing a resin layer softer than the cured layer, the impact resistance of the laminate can be improved. Furthermore, the ratio of the storage modulus of the second resin layer to the first resin layer is set within a specific range. That is, the storage modulus of the first resin layer and the storage modulus of the second resin layer are set to be approximately the same. This further improves the flexibility of the laminate.

[0036] Furthermore, by arranging the highly flexible resin layer near the cured layer, i.e., by arranging the first resin layer near the first cured layer and the second resin layer near the second cured layer, it is believed that each cured layer bends following the resin layer, thereby improving the flexibility of the entire laminate.

[0037] Cross-sectional view of the basic layer structure of a laminate Cross-sectional view of the basic layer structure of a laminate having a glass layer Cross-sectional view of the basic layer structure of a laminate having a glass layer Schematic diagram showing an example of a method for producing thin film glass Example of application to an organic EL display, which is an example of a display device

[0038] The laminate of the present invention has a resin layer, a cured layer, and an adhesive layer. The laminate of the present invention is a laminate comprising a first cured layer, a first resin layer, a first adhesive layer, a second cured layer, and a second resin layer laminated in this order. The first resin layer contains a dye compound whose maximum absorption wavelength is in the range of 360 to 379 nm in the ultraviolet-visible light absorption spectrum of a wavelength range of 300 to 460 nm. The first resin layer has an average light transmittance of 87% or more in the wavelength range of 450 to 800 nm. The first resin layer has a storage modulus at 25°C in the range of 4.0 to 8.0 GPa. The ratio of the storage modulus at 25°C of the second resin layer to that of the first resin layer is in the range of 0.7 to 1.5. The laminate is characterized by the above. This feature is a technical feature common to or corresponding to the following embodiments.

[0039] In an embodiment of the present invention, the first resin layer preferably contains a cellulose ester, from the viewpoints of easily adding additives to the resin and adjusting the light transmittance and storage modulus of the resin layer to desired values.

[0040] In an embodiment of the present invention, from the viewpoint of being able to adjust the light transmittance of the resin layer to a desired value, it is preferable that the dye compound has a structure represented by the above general formula (1).

[0041] In an embodiment of the present invention, from the viewpoint of being able to adjust the light transmittance of the resin layer to a desired value, it is preferable that the dye compound has a structure represented by the above general formula (2).

[0042] In an embodiment of the present invention, from the viewpoint of being able to adjust the light transmittance and storage modulus of the resin layer to desired values ​​and obtaining flexibility, it is preferable that the thickness of the first resin layer is within the range of 15 to 50 μm.

[0043] In an embodiment of the present invention, from the viewpoint of obtaining impact resistance, it is preferable that the storage modulus at 25° C. of the second resin layer is within a range of 4.0 to 8.0 GPa.

[0044] In an embodiment of the present invention, from the viewpoint of being a cover member having a glass layer, it is preferable that the cover member further has a glass layer, and is laminated in the following order: the first hardened layer, the first resin layer, the first adhesive layer, the second hardened layer, the second resin layer, and the glass layer.

[0045] In an embodiment of the present invention, from the viewpoint of attaching a glass layer, it is preferable that the laminate further has a second adhesive layer, and is laminated in the following order: the first hardened layer, the first resin layer, the first adhesive layer, the second hardened layer, the second resin layer, the second adhesive layer, and the glass layer.

[0046] In an embodiment of the present invention, from the viewpoint of making the cover member thinner, the thickness of the glass layer is preferably within a range of 10 to 30 μm.

[0047] In an embodiment of the present invention, from the viewpoint of attachment to a display device, it is preferable that the laminate further has a third adhesive layer, and is laminated in the following order: the first hardened layer, the first resin layer, the first adhesive layer, the second hardened layer, the second resin layer, the second adhesive layer, the glass layer, and the third adhesive layer.

[0048] A display device according to the present invention is characterized by comprising the laminate.

[0049] In an embodiment of the present invention, from the viewpoint of achieving a significant effect, it is preferable that the first resin layer of the laminate be disposed closer to the viewing side of the display device than the second resin layer.

[0050] The present invention, its components, and modes and aspects for carrying out the present invention will be described in detail below. In this application, the symbol "to" is used to mean that the numerical values ​​before and after it are included as the lower limit and upper limit.

[0051] 1. Overview of the Laminate The laminate of the present invention has a resin layer, a cured layer, and an adhesive layer. The laminate of the present invention is a laminate having a first cured layer, a first resin layer, a first adhesive layer, a second cured layer, and a second resin layer laminated in this order. The first resin layer contains a dye compound whose maximum absorption wavelength is in the range of 360 to 379 nm in the ultraviolet-visible light absorption spectrum of a wavelength region of 300 to 460 nm. The first resin layer has an average light transmittance of 87% or more in the wavelength region of 450 to 800 nm. The first resin layer has a storage modulus at 25°C in the range of 4.0 to 8.0 GPa. The ratio of the storage modulus at 25°C of the second resin layer to that of the first resin layer is in the range of 0.7 to 1.5.

[0052] The laminate of the present invention is used as a protective member for thin-film glass (protective film for glass). Preferably, the laminate of the present invention is attached to thin-film glass and used as a cover member for a display device. The laminate may have other layers as needed in addition to the resin layer, cured layer, and adhesive layer.

[0053] 1 is a cross-sectional view of the basic layer structure of a laminate. The laminate 10 is formed by laminating a first cured layer 1, a first resin layer 2, a first adhesive layer 3, a second cured layer 4, and a second resin layer 5 in this order. The first cured layer 1 and the second cured layer 4 may be made of the same material and have the same physical properties, or may have different materials and physical properties. Furthermore, the first resin layer 2 and the second resin layer 5 may be made of the same material and have the same physical properties, or may have different materials and physical properties, as long as they satisfy the storage modulus requirements.

[0054] The laminate 10 has a first adhesive layer 3 between the first resin layer 2 and the second cured layer 4. If necessary, an adhesive layer may be further provided between the first cured layer 1 and the first resin layer 2 or between the second cured layer 4 and the second resin layer 5.

[0055] 2 and 3 are cross-sectional views of the basic layer structure of a laminate having a glass layer. As shown in Fig. 2, the laminate 11 may further include a glass layer 6 on the surface of the second resin layer 5 opposite to the second cured layer 4. As shown in Fig. 3, the laminate 12 may include a second adhesive layer between the second resin layer 5 and the glass layer 6. The second adhesive layer may be made of the same material and have the same physical properties as the first adhesive layer, or may be made of a different material and have different physical properties.

[0056] From the viewpoint of storage modulus, the first resin layer and the second resin layer preferably have similar properties. On the other hand, from the viewpoint of light transmittance, the first resin layer and the second resin layer do not necessarily have similar properties. In other words, the light transmittance of the second resin layer is not particularly limited.

[0057] 2. Structure of the Laminate The laminate of the present invention has a cured layer, a resin layer, and an adhesive layer. It may further have a glass layer. The cured layer, the resin layer, the adhesive layer, and the glass layer will be described below.

[0058] (1) Hardened Layer The laminate of the present invention has a hardened layer, which can improve the impact resistance of a display device when the laminate is attached. Furthermore, by dividing the hardened layer into two layers, it is thought that the flexibility of a display device when the laminate is attached can be improved while maintaining the impact resistance.

[0059] In the present invention, the term "cured layer" refers to a layer formed by curing a resin by heating or irradiating it with active energy rays. The cured layer preferably exhibits a hardness of "HB" or higher in the pencil hardness test specified in JIS K5600-2014.

[0060] As described above, the first and second hardened layers may be made of the same material and have the same physical properties, or may be made of different materials and have different physical properties.

[0061] From the viewpoint of mechanical strength such as scratch resistance and pencil hardness, the thickness of the cured layer is preferably in the range of 0.01 to 20 μm, and more preferably in the range of 0.5 to 10 μm.

[0062] The curable layer may be made of the same material as the adhesive layer described below. However, the curable layer satisfies the above-mentioned hardness requirements and does not have adhesiveness. Specifically, the curable layer does not have adhesiveness sufficient to attach the laminate to a display device or to bond each layer in the laminate.

[0063] (1.1) Materials Constituting the Cured Layer The resin and other additives contained in the cured layer will be described below.

[0064] (1.1.1) Resin There are no particular limitations on the resin, as long as it is a curable resin that is cured by heating or irradiation with active energy rays. Among them, an active energy ray-curable resin is preferred from the viewpoint of curing at room temperature in a short time. Furthermore, the active energy ray-curable resin is preferably a resin containing a monomer having an ethylenically unsaturated double bond.

[0065] Examples of active energy rays include ultraviolet rays and electron beams. Among them, ultraviolet rays are preferred from the viewpoint of mechanical strength such as scratch resistance, impact resistance, and pencil hardness.

[0066] The active energy ray-curable resin is preferably an acrylic material. Examples of acrylic materials include monofunctional or polyfunctional (meth)acrylate compounds such as (meth)acrylic acid esters of polyhydric alcohols, and polyfunctional urethane (meth)acrylate compounds synthesized from diisocyanates, polyhydric alcohols, and hydroxy esters of (meth)acrylic acid. In addition to these, other examples include polyethers, polyesters, epoxy resins, alkyd resins, spiroacetal resins, polybutadiene, and polyene-polythiol resins having acrylate functional groups.

[0067] Among these resins, those that are cured by ultraviolet light are more preferred. For example, ultraviolet-curable acrylate resins, ultraviolet-curable urethane acrylate resins, ultraviolet-curable polyester acrylates, ultraviolet-curable epoxy acrylate resins, ultraviolet-curable polyol acrylates, ultraviolet-curable epoxy resins, etc. are preferred. Among these, ultraviolet-curable acrylate resins are preferred.

[0068] The cured layer is formed using, for example, a composition for forming a cured layer containing an active energy ray-curable resin, a polymerization initiator, and a solvent. The solvent contained in the composition for forming a cured layer is preferably a solvent that dissolves or swells the resin layer. By dissolving or swelling the resin layer with the solvent, the composition for forming a cured layer can easily penetrate from the surface to the inside of the resin layer, thereby improving the adhesion between the resin layer and the cured layer.

[0069] (1.1.2) Other Additives From the viewpoints of increasing hardness, suppressing cure shrinkage, preventing blocking, controlling the refractive index, imparting antiglare properties, controlling the properties of the cured layer surface, etc., the cured layer may contain conventionally known fine particles, dispersants, antistatic agents, silane coupling agents, thickeners, coloring inhibitors, colorants (pigments or dyes), antifoaming agents, flame retardants, adhesion promoters, polymerization inhibitors, antioxidants, surface modifiers, etc. The cured layer may also contain a photosensitizer. Examples of photosensitizers include n-butylamine, triethylamine, and poly-n-butylphosphine.

[0070] From the viewpoint of suppressing dimensional fluctuations, the cured layer preferably contains fine particles. The content of the fine particles is preferably within a range of 100 to 400% with respect to the total mass of the active energy ray-curable resin. The fine particles are not particularly limited, but are preferably fine particles made of a metal oxide. Hereinafter, fine particles made of a metal oxide will also be referred to as "metal oxide particles."

[0071] Examples of metal oxides include silica, alumina, zirconia, titanium oxide, and antimony pentoxide. Among these, the metal oxide particles are preferably composed of silica. The silica fine particles may be hollow particles having cavities formed therein.

[0072] The fine particles are preferably coated with a polymeric silane coupling agent. By coating the surfaces of the fine particles with a polymeric silane coupling agent, the fine particles can be uniformly dispersed in the composition for forming a cured layer. The average particle diameter of the fine particles coated with a polymeric silane coupling agent is preferably within the range of 5 to 500 nm, and more preferably within the range of 10 to 200 nm. By having the average particle diameter within the above range, the optical properties of the cured layer can be improved.

[0073] The polymeric silane coupling agent is prepared by reacting a polymerizable monomer with a silane coupling agent (reactive silane compound). Examples of the polymerizable monomer include a monomer having an ethylenically unsaturated double bond, and among these, a monomer selected from (meth)acrylic acid and its derivatives is preferred. Examples of the reactive silane compound are hydrolyzable silane compounds in which three alkoxy groups and one functional group are bonded to a silicon atom. Examples of functional groups bonded to the silicon atom include (meth)acryloxy groups, epoxy groups (glycidyl groups), urethane groups, amino groups, fluoro groups, and mercapto groups.

[0074] The polymeric silane coupling agent can be synthesized, for example, according to the method for producing a reaction product of a polymerizable monomer and a reactive silane compound disclosed in JP-A-11-116240. The number average molecular weight of the polymeric silane coupling agent, calculated as polystyrene, is preferably in the range of 2,500 to 150,000, and more preferably in the range of 2,000 to 100,000.

[0075] A method for coating the surfaces of fine particles with a polymeric silane coupling agent will be described using silica fine particles as an example. First, a dispersion is prepared by dispersing silica fine particles and a polymeric silane coupling agent in an organic solvent. An alkali is added to this dispersion to generate OH groups on the surfaces of the silica fine particles. The polymeric silane coupling agent is adsorbed onto the OH groups. Alternatively, the OH groups are bonded to the OH groups of the polymeric silane coupling agent by a dehydration reaction. Finally, the silica fine particles to which the polymeric silane coupling agent has been adsorbed or bonded are separated from the dispersion and dried. This yields silica fine particles coated with the polymeric silane coupling agent.

[0076] (1.2) Method for Producing Cured Layer The method for preparing the composition for forming a cured layer is not particularly limited as long as it is a method that can uniformly mix the solid components contained in the cured layer into a solvent. For example, the composition for forming a cured layer can be prepared by mixing or dissolving the solid components and the solvent using a known device such as a paint shaker, a bead mill, a kneader, or a mixer.

[0077] The cured layer can be formed, for example, by applying a composition for forming a cured layer to the surface of the resin layer and curing the active energy ray-curable resin in the coating film. The method for applying the composition for forming a cured layer is not particularly limited, and a conventionally known method can be applied.

[0078] The coating method is preferably, for example, a microgravure coating method from the viewpoint of forming a uniform thin layer. Furthermore, a die coating method is preferable from the viewpoint of forming a thick layer. After removing the solvent from the coating film as necessary, the coating film is irradiated with active energy rays to cure the active energy ray-curable resin, thereby obtaining a cured layer.

[0079] The cured layer does not necessarily have to be formed directly on the surface of the resin layer. The cured layer may be formed on a support, peeled from the support, and then bonded to the resin layer via an adhesive layer.

[0080] (2) Resin Layer The first resin layer according to the present invention contains a dye compound whose maximum absorption wavelength is in the range of 360 to 379 nm in the ultraviolet-visible light absorption spectrum in the wavelength region of 300 to 460 nm. The first resin layer according to the present invention has an average light transmittance of 87% or more in the wavelength region of 450 to 800 nm (visible light region). The first resin layer according to the present invention also has a storage modulus at 25°C in the range of 4.0 to 8.0 GPa. Furthermore, the ratio of the storage modulus at 25°C of the second resin layer according to the present invention to that of the first resin layer is in the range of 0.7 to 1.5.

[0081] The laminate of the present invention is believed to have a resin layer, thereby improving the light resistance and flexibility of a display device when the laminate is attached. Furthermore, the first resin layer is disposed near the first cured layer, and the second resin layer is disposed near the second cured layer. This allows each cured layer to bend in accordance with the resin layer, improving the flexibility of the entire laminate.

[0082] In the present invention, the term "resin layer" refers to a layer containing a resin as a main component and not corresponding to the cured layer or the adhesive layer described below. The first resin layer and the second resin layer may be made of the same material and have the same physical properties, or may be made of different materials and have different physical properties, as long as they satisfy the conditions of light transmittance and storage modulus.

[0083] The light transmittance of the resin layer can be adjusted by incorporating a dye or the like into the resin layer. The storage modulus of the resin layer can be adjusted by incorporating a plasticizer, particles (rubber particles, metal oxide particles, etc.), fibers (acicular particles, cellulose nanofibers, etc.) into the resin layer. Conventionally known plasticizers, particles, and fibers can be used. The storage modulus of the resin layer can also be adjusted by the production conditions of the resin layer.

[0084] (2.1) Constituent Materials of Resin Layer Hereinafter, the film-forming components contained in the resin layer, such as the resin, dye compound, plasticizer, rubber particles, UV absorber, antioxidant, fine particles, and other additives, will be described.

[0085] (2.1.1) Resin The resin contained in the resin layer as a film-forming component is preferably a thermoplastic resin material, and is not limited as long as it can be handled as a film after film formation. Examples of thermoplastic resins include cellulose esters such as triacetyl cellulose (TAC), cellulose acetate propionate (CAP), and diacetyl cellulose (DAC); (meth)acrylic resins such as polymethyl methacrylate (PMMA) and styrene-(meth)acrylate copolymers; cyclic olefin resins such as cycloolefin resins (COP); and polyesters such as polyethylene terephthalate (PET).

[0086] Among these, the resin is preferably a cellulose ester, from the viewpoint of easily forming an intermolecular network and imparting rigidity to the resin layer. In addition, the cellulose ester can be added with a dye, a plasticizer, particles, fibers, etc.

[0087] (2.1.1.1) Cellulose Esters Cellulose is a polymer in which β-glucose units are linked in a linear chain via β-1,4-glycosidic bonds. Cellulose esters are cellulose in which some or all of the hydrogen atoms of the hydroxyl groups (—OH) at the 2-, 3-, and 6-positions in one glucose unit have been substituted with acyl groups.

[0088] The cellulose ester is not particularly limited, but is preferably an ester of a linear or branched carboxylic acid having a carbon number of about 2 to 22. Examples of the carboxylic acid constituting the ester include aliphatic carboxylic acids, alicyclic carboxylic acids, and aromatic carboxylic acids.

[0089] Examples of the substituted acyl group of the cellulose ester include acyl groups having 2 to 22 carbon atoms, such as acetyl, propionyl, butyryl, isobutyryl, valeryl, pivaloyl, hexanoyl, octanoyl, lauroyl, and stearoyl.

[0090] The carboxylic acid (acyl group) constituting the ester may have a substituent. The carboxylic acid constituting the ester is preferably a lower fatty acid having 6 or less carbon atoms, more preferably a lower fatty acid having 3 or less carbon atoms.

[0091] The cellulose ester may contain a single type of acyl group or a combination of multiple acyl groups.

[0092] Specific examples of cellulose esters include cellulose acetates such as diacetyl cellulose (DAC) and triacetyl cellulose (TAC). Also included are mixed fatty acid esters of cellulose to which a propionate group or a butyrate group is bonded in addition to an acetyl group, such as cellulose acetate propionate (CAP), cellulose acetate butyrate, and cellulose acetate propionate butyrate. The cellulose esters may be contained alone or in combination of two or more.

[0093] <Type and Degree of Substitution of Acyl Group> By appropriately selecting the type and degree of substitution of the acyl group of the cellulose ester, it is possible to control the humidity fluctuation of the retardation of the resin layer within a desired range, thereby improving the thickness uniformity of the resin layer.

[0094] The degree of acyl substitution represents the average number of acyl groups per glucose unit. In other words, it represents how many of the hydrogen atoms in the hydroxy groups at positions 2, 3, and 6 in one glucose unit are substituted with acyl groups. Therefore, the maximum degree of acyl substitution is 3.0, which means that all of the hydrogen atoms in the hydroxy groups at positions 2, 3, and 6 are substituted with acyl groups.

[0095] The acyl groups may be substituted evenly at the 2-, 3-, and 6-positions of one glucose unit, or may be substituted with a distribution. The degree of acyl substitution is determined by the method specified in ASTM-D817-96.

[0096] If the substitution degree of the acyl group of the cellulose ester is too large, the retardation is difficult to exhibit, so it is necessary to increase the stretching ratio when preparing the resin layer. However, it is difficult to uniformly stretch at a high stretching ratio, and the thickness of the resin layer is likely to vary greatly. On the other hand, the smaller the substitution degree of the acyl group of the cellulose ester, the easier it is to exhibit retardation, so the thickness of the resin layer can be made thin and uniform. However, if the substitution degree of the acyl group of the cellulose ester is too small, the durability of the resin layer decreases, so from the viewpoint of durability, it is preferable not to make the substitution degree too small.

[0097] The humidity-dependent change in thickness retardation (Rt) occurs due to the coordination of water molecules with the carbonyl groups of cellulose. Therefore, the smaller the degree of acyl substitution, i.e., the fewer carbonyl groups in the cellulose, the less humidity-dependent change in Rt can be.

[0098] The degree of substitution of the acyl group in the cellulose ester is preferably within the range of 2.1 to 3.0. By keeping the degree within this range, environmental fluctuations (especially fluctuations in Rt due to humidity) can be suppressed, and the thickness uniformity of the resin layer can be improved. Furthermore, the flowability and stretchability during the production of the resin layer can be improved.

[0099] The degree of substitution of the acyl group in the cellulose ester preferably satisfies both of the following formulas (a) and (b): In the formulas (a) and (b), X is the degree of substitution of the acetyl group, and Y is the degree of substitution of the propionyl group or the butyryl group, or a mixture thereof.

[0100] Formula (a): 2.1≦X+Y≦2.5 Formula (b): 0≦Y≦1.5

[0101] The cellulose ester is preferably cellulose acetate (Y=0) or cellulose acetate propionate (CAP) (Y: propionyl group, Y>0). Of these, cellulose acetate where Y=0 is preferred from the viewpoint of uniformity of the thickness of the resin layer.

[0102] From the viewpoints of retardation expression, humidity-dependent variation of Rt, and resin layer uniformity, the degree of substitution X of the acetyl group in cellulose acetate preferably satisfies 2.1≦X≦3.0. Examples of cellulose acetates that satisfy the above range include cellulose diacetate (DAC) and cellulose triacetate (TAC).

[0103] When Y>0, the cellulose ester is preferably cellulose acetate propionate (CAP), and X and Y preferably satisfy any of the following conditions: 0.95≦X≦2.25, 0.1≦Y≦1.2, and 2.15≦X+Y≦2.45.

[0104] By using cellulose acetate or cellulose acetate propionate that satisfies these conditions, a resin layer that is excellent in retardation, mechanical strength, and resistance to environmental changes can be obtained.

[0105] In order to obtain desired optical properties, cellulose acetates having different degrees of substitution may be mixed and used. The mixing ratio of different cellulose acetates is not particularly limited.

[0106] From the viewpoint of mechanical strength, the number average molecular weight (Mn) of the cellulose ester is 2×10 ４ ~3 x 10 ５ It is preferable that the range is 2×10 ４ ~1.2 × 10 ５ More preferably, it is within the range of 4×10 ４ ~8 x 10 ４ It is more preferable that the range is within the range of

[0107] The number average molecular weight (Mn) of the cellulose ester can be measured in the same manner as in the (meth)acrylic resin described below.

[0108] From the viewpoint of mechanical strength, the weight average molecular weight (Mw) of the cellulose ester is 2×10 ４ ~1 x 10 ６ It is preferable that the range is 2×10 ４ ~1.2 × 10 ５ More preferably, it is within the range of 4×10 ４ ~8 x 10 ４It is more preferable that the range is within the range of

[0109] The raw cellulose for the cellulose ester is not particularly limited, but examples thereof include cotton linter, wood pulp, kenaf, etc. Cellulose esters obtained from these may be mixed in any desired ratio.

[0110] Cellulose esters such as cellulose acetate and cellulose acetate propionate can be synthesized by known methods.

[0111] Generally, raw materials such as cellulose, an organic acid (acetic acid, propionic acid, etc.), an acid anhydride (acetic anhydride, propionic anhydride, etc.), and a catalyst (sulfuric acid, etc.) are mixed together, and the cellulose is esterified, and the reaction is continued until a cellulose triester is produced.

[0112] In triesters, the three hydroxy groups in one glucose unit are substituted with an acyl group of an organic acid.

[0113] By using two kinds of organic acids at the same time, mixed ester type cellulose esters, such as cellulose acetate propionate and cellulose acetate butyrate, can be synthesized.

[0114] Next, the cellulose triester is hydrolyzed to obtain a cellulose ester having a desired degree of acyl substitution. After that, the cellulose ester is finally obtained through steps such as filtration, precipitation, washing with water, dehydration, and drying. Specifically, the cellulose ester can be synthesized by referring to the method described in JP-A-10-45804.

[0115] (2.1.1.2) Cycloolefin Resin The cycloolefin resin is preferably a polymer of a cycloolefin monomer or a copolymer of a cycloolefin monomer and another monomer copolymerizable with the cycloolefin monomer.

[0116] The cycloolefin monomer is preferably a cycloolefin monomer having a norbornene skeleton, and more preferably a cycloolefin monomer having a structure represented by the following general formula (A-1) or (A-2):

[0117]

[0118] In the above general formula (A-1), R １ ~R ４ each independently represents a hydrogen atom, a hydrocarbon group having 1 to 30 carbon atoms, or a polar group, and p represents an integer of 0 to 2. １ ~R ４ do not all represent hydrogen atoms at the same time, and R １ and R ２ does not simultaneously represent a hydrogen atom, and R ３ and R ４ does not simultaneously represent a hydrogen atom.

[0119] In the above general formula (A-1), R １ ~R ４ The hydrocarbon group having 1 to 30 carbon atoms represented by the formula (I) is preferably a hydrocarbon group having 1 to 10 carbon atoms, and more preferably a hydrocarbon group having 1 to 5 carbon atoms. The hydrocarbon group having 1 to 30 carbon atoms may further have a linking group containing, for example, a halogen atom, an oxygen atom, a nitrogen atom, a sulfur atom, or a silicon atom. Examples of such linking groups include divalent polar groups such as a carbonyl group, an imino group, an ether bond, a silyl ether bond, and a thioether bond. Examples of the hydrocarbon group having 1 to 30 carbon atoms include a methyl group, an ethyl group, a propyl group, and a butyl group.

[0120] In the above general formula (A-1), R １ ~R ４ Examples of the polar group represented by the formula (I) include a carboxy group, a hydroxy group, an alkoxy group, an alkoxycarbonyl group, an aryloxycarbonyl group, an amino group, an amide group, and a cyano group. Among these, a carboxy group, a hydroxy group, an alkoxycarbonyl group, or an aryloxycarbonyl group is preferred. In particular, an alkoxycarbonyl group or an aryloxycarbonyl group is preferred from the viewpoint of solubility during solution casting.

[0121] In the general formula (A-1), p is preferably 1 or 2 from the viewpoint of improving heat resistance. When p is 1 or 2, the resulting polymer is bulky and the glass transition temperature is likely to be increased. In addition, the polymer becomes somewhat responsive to humidity, making it easier to control the curl balance of a laminate having a resin layer.

[0122]

[0123] In the above general formula (A-2), R ５ represents a hydrogen atom, a hydrocarbon group having 1 to 5 carbon atoms, or an alkylsilyl group having an alkyl group having 1 to 5 carbon atoms. ６ represents a carboxy group, a hydroxy group, an alkoxycarbonyl group, an aryloxycarbonyl group, an amino group, an amido group, a cyano group, or a halogen atom (a fluorine atom, a chlorine atom, a bromine atom, or an iodine atom), and p represents an integer of 0 to 2.

[0124] R in the above general formula (A-2) ５ is preferably a hydrocarbon group having 1 to 5 carbon atoms, and more preferably a hydrocarbon group having 1 to 3 carbon atoms.

[0125] R in the above general formula (A-2) ６ is preferably a carboxy group, a hydroxy group, an alkoxycarbonyl group, or an aryloxycarbonyl group, and is more preferably an alkoxycarbonyl group or an aryloxycarbonyl group from the viewpoint of solubility during solution casting.

[0126] From the viewpoint of improving heat resistance, p in the above general formula (A-2) is preferably 1 or 2. When p is 1 or 2, the obtained polymer is bulky and the glass transition temperature is likely to be improved.

[0127] From the viewpoint of improving the solubility in organic solvents, the cycloolefin monomer is preferably a cycloolefin monomer having a structure represented by the above general formula (A-2). In general, by breaking the symmetry of an organic compound, the crystallinity decreases and the solubility in organic solvents improves. R in general formula (A-2) ５ and R ６is substituted on only one side of the carbon atoms constituting the ring with respect to the axis of symmetry of the molecule, and therefore has low molecular symmetry. In other words, a cycloolefin monomer having a structure represented by general formula (A-2) has high solubility and is therefore suitable when a resin layer is produced by a solution casting method.

[0128] The content of the cycloolefin monomer having the structure represented by general formula (A-2) in the cycloolefin resin is preferably 70 mol% or more relative to the total number of moles of all cycloolefin monomers constituting the cycloolefin resin. Also, 80 mol% or more is more preferable, and 100 mol% is even more preferable. When the content of the cycloolefin monomer having the structure represented by general formula (A-2) is 70 mol% or more, the orientation of the cycloolefin resin is enhanced, and the phase difference (retardation) value is likely to increase.

[0129] Specific examples of cycloolefin monomers having a structure represented by general formula (A-1) are shown below as Exemplary Compounds 1 to 14. Specific examples of cycloolefin monomers having a structure represented by general formula (A-2) are shown below as Exemplary Compounds 15 to 34.

[0130]

[0131] Examples of copolymerizable monomers copolymerizable with cycloolefin monomers include copolymerizable monomers capable of ring-opening copolymerization with cycloolefin monomers, and copolymerizable monomers capable of addition copolymerization with cycloolefin monomers.

[0132] Examples of copolymerizable monomers capable of ring-opening copolymerization include cycloolefins such as cyclobutene, cyclopentene, cycloheptene, cyclooctene, and dicyclopentadiene.

[0133] Examples of copolymerizable monomers capable of addition copolymerization include unsaturated double bond-containing compounds, vinyl cyclic hydrocarbon monomers, (meth)acrylates, etc. Examples of unsaturated double bond-containing compounds include olefin compounds having 2 to 12 carbon atoms (preferably 2 to 8), such as ethylene, propylene, and butene. Examples of vinyl cyclic hydrocarbon monomers include vinylcyclopentene-based monomers such as 4-vinylcyclopentene and 2-methyl-4-isopropenylcyclopentene. Examples of (meth)acrylates include alkyl (meth)acrylates having 1 to 20 carbon atoms, such as methyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, and cyclohexyl (meth)acrylate.

[0134] The content of the cycloolefin monomer in the copolymer of a cycloolefin monomer and a copolymerizable monomer is preferably in the range of 20 to 80 mol %, more preferably in the range of 30 to 70 mol %, based on the total of all monomers constituting the copolymer.

[0135] As described above, the cycloolefin resin is a polymer obtained by homopolymerizing or copolymerizing a cycloolefin monomer having a norbornene skeleton, preferably a cycloolefin monomer having a structure represented by the above general formula (A-1) or (A-2). Examples of such polymers include the following: 1) a ring-opening polymer of a cycloolefin monomer; 2) a ring-opening copolymer of a cycloolefin monomer and a copolymerizable monomer capable of ring-opening copolymerization with the cycloolefin monomer; 3) a hydrogenated product of the ring-opening (co)polymer of 1) or 2) above; 4) a (co)polymer obtained by cyclizing the ring-opening (co)polymer of 1) or 2) above by the Friedel-Crafts reaction and then hydrogenating it; 5) a saturated copolymer of a cycloolefin monomer and an unsaturated double bond-containing compound; 6) an addition copolymer of a cycloolefin monomer with a vinyl-based cyclic hydrocarbon monomer and a hydrogenated product thereof; and 7) an alternating copolymer of a cycloolefin monomer and a (meth)acrylate.

[0136] The polymers 1) to 7) above can all be obtained by known methods, such as those described in JP-A-2008-107534 and JP-A-2005-227606. For example, the catalyst and solvent used in the ring-opening copolymerization 2) above can be those described in paragraphs 0019 to 0024 of JP-A-2008-107534. The catalyst used in the hydrogenation 3) and 6) above can be those described in paragraphs 0025 to 0028 of JP-A-2008-107534. The acidic compound used in the Friedel-Crafts reaction 4) above can be those described in paragraph 0029 of JP-A-2008-107534. The catalyst used in the addition polymerization 5) to 7) above can be those described in paragraphs 0058 to 0063 of JP-A-2005-227606. The alternating copolymerization reaction of 7) above can be carried out by, for example, the method described in paragraphs 0071 to 0072 of JP-A No. 2005-227606.

[0137] Among these, a polymer of 1) to 3) or 5) above is preferred, and a polymer of 3) or 5) above is more preferred. That is, from the viewpoint of increasing the glass transition temperature and light transmittance of the resulting resin, the cycloolefin resin preferably contains at least one of a structural unit represented by the following general formula (B-1) and a structural unit represented by the following general formula (B-2). It is more preferred that the cycloolefin resin contains only a structural unit represented by the general formula (B-2), or contains both a structural unit represented by the general formula (B-1) and a structural unit represented by the general formula (B-2). The structural unit represented by the general formula (B-1) is a structural unit derived from the cycloolefin monomer represented by the aforementioned general formula (A-1), and the structural unit represented by the general formula (B-2) is a structural unit derived from the cycloolefin monomer represented by the aforementioned general formula (A-2).

[0138]

[0139] In the general formula (B-1), X is —CH═CH— or —CH ２ CH ２ - represents. １ ~R ４ and p are R in the general formula (A-1) １ ~R４ and p.

[0140]

[0141] In the general formula (B-2), X is —CH═CH— or —CH ２ CH ２ - represents. ５ ~R ６ and p are R in general formula (A-2), ５ ~R ６ and p.

[0142] The cycloolefin resin used in the present invention may be a commercially available product. Examples of commercially available cycloolefin resins include "ARTON (registered trademark) G780," "ARTON (registered trademark) F," "ARTON (registered trademark) R4500, R4900, R5000," and "ARTON (registered trademark) RX4500" (all manufactured by JSR Corporation).

[0143] The intrinsic viscosity [η]inh of the cycloolefin resin at 30°C is 0.2 to 5 cm ３ / g, and 0.3 to 3 cm ３ / g, and more preferably in the range of 0.4 to 1.5 cm ３ It is more preferable that the range is 1 / g.

[0144] The number average molecular weight (Mn) of the cycloolefin resin is preferably within the range of 8,000 to 100,000, more preferably within the range of 10,000 to 80,000, and even more preferably within the range of 12,000 to 50,000. The weight average molecular weight (Mw) of the cycloolefin resin is preferably within the range of 20,000 to 300,000, more preferably within the range of 30,000 to 250,000, and even more preferably within the range of 40,000 to 200,000. The weight average molecular weight (Mw) can be measured by the same method as for the (meth)acrylic resin described above.

[0145] When the intrinsic viscosity [η]inh, number average molecular weight, and weight average molecular weight (Mw) are within the above ranges, the cycloolefin resin has good heat resistance, water resistance, chemical resistance, mechanical properties, and moldability as a resin layer.

[0146] The glass transition temperature (Tg) of the cycloolefin resin is usually 110°C or higher, preferably in the range of 110 to 350°C, more preferably in the range of 120 to 250°C, and even more preferably in the range of 120 to 220°C. When the Tg is 110°C or higher, deformation under high temperature conditions can be suppressed. On the other hand, when the Tg is 350°C or lower, molding processing becomes easy and deterioration of the resin due to heat during molding processing can be suppressed.

[0147] The content of the cycloolefin resin is preferably 70% by mass or more, and more preferably 80% by mass or more, based on the total mass of the resin layer.

[0148] (2.1.1.3) Polyimide Polyimide is synthesized by the polymerization reaction of tetracarboxylic dianhydride and diamine.

[0149] Examples of the tetracarboxylic dianhydride include aromatic tetracarboxylic dianhydrides, aliphatic tetracarboxylic dianhydrides, and alicyclic tetracarboxylic dianhydrides. Of these, aromatic tetracarboxylic dianhydrides are preferred. Examples of the diamine include aromatic diamines, aliphatic diamines, and alicyclic diamines. Of these, aromatic diamines are preferred.

[0150] The weight-average molecular weight (Mw) of the polyimide is preferably in the range of 100,000 to 300,000, and more preferably in the range of 130,000 to 250,000. By having it in the above range, it is possible to prevent the resin layer from being broken by the conveying tension during conveyance of the resin layer. The weight-average molecular weight (Mw) can be measured in the same manner as for the (meth)acrylic resin described above.

[0151] The content of polyimide is preferably 60% by mass or more, and more preferably 70% by mass or more, based on the total mass of the resin layer.

[0152] (2.1.2) Dye Compound The first resin layer contains a dye compound. The dye compound has a maximum absorption wavelength in the range of 360 to 379 nm in the ultraviolet-visible light absorption spectrum in the wavelength range of 300 to 460 nm. By including the dye compound, the light transmittance in a certain wavelength range can be adjusted to fall within a specific range. Hereinafter, unless otherwise specified, the maximum absorption wavelength of various dye compounds refers to the maximum absorption wavelength in the absorption spectrum in the wavelength range of 300 to 460 nm.

[0153] The dye compound has the above-described light absorption characteristics, thereby protecting a light-emitting element (particularly an organic EL element) or a light-emitting device from external light and suppressing deterioration. The dye compound is not particularly limited as long as it has the above-described light absorption characteristics. However, it is preferable that the dye compound does not have fluorescence or phosphorescence properties (photoluminescence), which would impair the display properties of an organic EL element.

[0154] The dye compound is not particularly limited in structure, etc., as long as it has the above-described light absorption characteristics. Examples of the dye compound include organic compounds and inorganic compounds. From the viewpoints of dispersibility in the resin component and transparency of the first resin layer, the dye compound is preferably an organic compound.

[0155] Examples of the organic compound include azomethine compounds, indole compounds, cinnamic acid compounds, pyrimidine compounds, methine compounds, porphyrin compounds, dicyanomethine compounds, and benzotriazole compounds. Of these, benzotriazole compounds are preferred.

[0156] The benzotriazole-based compound preferably has a structure represented by the following general formula (1) or (2). Dye compounds having these structures have extremely high ultraviolet absorption ability and low light absorptance in the wavelength range of 450 to 800 nm. As a result, the average light transmittance of the first resin layer in the ultraviolet range can be extremely low, and the average light transmittance in the wavelength range of 450 to 800 nm can be adjusted to 87% or more.

[0157] From the viewpoints of dispersibility in the resin, which is a film-forming component of the first resin layer, and transparency of the first resin layer, the dye compound is preferably a compound having a structure represented by the following general formula (1) or (2). This compound has a substituent of a specific structure on the benzotriazole skeleton, and is therefore highly hydrophobic. This is thought to strengthen the interaction between the compound, the resin, and other additives, suppress decomposition of the compound by light, and improve the light resistance of the compound. Furthermore, due to the relationship between the sp values ​​of the resin and the compound, the resin and the compound are highly compatible. Therefore, even if the compound is contained in the resin in an amount necessary to form a desired absorption spectrum, it is thought that bleed-out and whitening are unlikely to occur.

[0158]

[0159] (In the formula, R １１ represents a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group, a hydroxy group, an amino group, an alkyl-substituted amino group, a carboxy group, an alkyloxycarbonyl group, a hydroxyalkyl group, an alkylcarbonyloxyalkyl group, a carboxyalkyl group, an alkyloxycarbonylalkyl group, an aryl group, an acyl group, or a sulfo group. １２ represents a hydrogen atom or a hydroxy group.

[0160]

[0161] (In the formula, R ２１ represents a hydrogen atom or a hydroxy group. ２２ , R ２３ , and R ２４ represents an alkyl group, an alkoxy group, an alkyl-substituted amino group, a carboxy group, an alkyloxycarbonyl group, a hydroxyalkyl group, an alkylcarbonyloxyalkyl group, a carboxyalkyl group, an alkyloxycarbonylalkyl group, an aryl group, an acyl group, or a sulfo group.

[0162] The above R １１ , R ２２ , R ２３ and R ２４The number of carbon atoms in the alkyl group portion of the substituent represented by the formula (I) is preferably in the range of 1 to 20, more preferably in the range of 1 to 10. The alkyl group portion may be linear, branched, cyclic, or a combination thereof. The number of carbon atoms in the aryl group is preferably in the range of 5 to 30. The aryl group may have a heteroatom. The aromatic ring in the aryl group may be a monocyclic ring or a condensed ring.

[0163] Examples of the alkyl group or alkyl group moiety include a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group, a tert-butyl group, an n-hexyl group, an n-octyl group, and a 2-ethylhexyl group. Examples of the aryl group include a phenoxy group, a naphthyloxy group, and a 2-methylphenoxy group. １１ , R ２２ , R ２３ and R ２４ The substituent represented by the formula (I) may further have a substituent.

[0164] Examples of compounds having the structures represented by general formula (1) and general formula (2) are shown below, but the dye compounds are not limited to these.

[0165]

[0166]

[0167]

[0168] The compounds having the structures represented by general formulas (1) and (2) according to the present invention can be synthesized by conventional methods. An example of the synthesis method is shown below. First, nitroanilines are diazotized. The resulting diazo compound is coupled with sesamol by a conventional method. The resulting nitrophenylazo compound is reduced to synthesize the desired benzotriazole derivative.

[0169]

[0170] Synthesis of 6-(5-methoxycarbonyl-2H-benzotriazol-2-yl)benzo[1,3]dioxol-5-ol

[0171]

[0172] A 300 mL four-neck flask is equipped with a ball condenser, a thermometer, and a stirrer. The following components are placed in the flask and stirred at 65 to 70°C for 3 hours.

[0173] 6-(5-carboxy-2H-benzotriazol-2-yl)benzo[1,3]dioxol-5-ol 1.10 g (0.0037 mol) Thionyl chloride 0.90 g (0.0076 mol) Toluene 173.38 g (200.0 mL) N,N-dimethylformamide 0.18 g (0.2 mL)

[0174] After the solvent was distilled off from the four-necked flask, the following components were added to the four-necked flask and stirred for 2 hours at a temperature of 70 to 75°C: 0.5 g (0.0156 mol) of methanol, 0.80 g (0.0101 mol) of pyridine, and 130.04 g (150.0 mL) of toluene.

[0175] The reaction product is washed twice with 100 mL of warm water. 0.1 g of activated carbon is added to the reaction product, and the mixture is refluxed and stirred to decolorize. The reaction product is then filtered while hot, and the filtrate is cooled to 5°C. The precipitated crystals are filtered, washed with toluene, and dried at 60°C to obtain 0.5 g of compound (1-8). The yield is 43%. The resulting compound (1-8) is 6-(5-methoxycarbonyl-2H-benzotriazol-2-yl)benzo[1,3]dioxol-5-ol, and has a maximum absorption wavelength of 377 nm.

[0176] (Measurement of Maximum Absorption Wavelength) The maximum absorption wavelength of a dye compound can be determined by measuring the absorption spectrum of the dye compound in chloroform using, for example, an ultraviolet-visible spectrophotometer "UV-2450" (manufactured by Shimadzu Corporation).

[0177] The "maximum absorption wavelength" in the present invention refers to the wavelength (nm) showing the maximum and maximal absorbance (absorption intensity) in the ultraviolet-visible light absorption spectrum of the dye compound obtained by measurement.

[0178] The dye compound may be used alone or in combination of two or more. The second resin layer may or may not contain a dye compound. The dye compound content is preferably within a range of 0.01 to 10% by mass, more preferably within a range of 0.02 to 8% by mass, relative to the total mass of the resin as a film-forming component. By ensuring that the dye compound content is within the above range, the resin layer can sufficiently absorb light in a wavelength range that does not affect the light emission of the light-emitting element or light-emitting device, thereby suppressing deterioration of the light-emitting element or light-emitting device due to external light.

[0179] (2.1.3) Plasticizer The resin layer preferably contains a plasticizer. By containing a plasticizer, the flexibility and processability of the resin layer can be improved. Examples of plasticizers include polyesters. Polyesters are obtained by polymerizing dicarboxylic acids and diols. Furthermore, it is preferable that 70% or more of the dicarboxylic acid structural units (structural units derived from dicarboxylic acids) are derived from aromatic dicarboxylic acids, and 70% or more of the diol structural units (structural units derived from diols) are derived from aliphatic diols.

[0180] The proportion of structural units derived from aromatic dicarboxylic acids is preferably 70% or more, more preferably 80% or more, and even more preferably 90% or more. The proportion of structural units derived from aliphatic diols is preferably 70% or more, more preferably 80% or more, and even more preferably 90% or more. The polyester may be contained alone or in combination of two or more.

[0181] Examples of aromatic dicarboxylic acids include terephthalic acid; isophthalic acid; naphthalenedicarboxylic acids such as 2,6-naphthalenedicarboxylic acid, 1,5-naphthalenedicarboxylic acid, and 2,7-naphthalenedicarboxylic acid; 4,4'-biphenyldicarboxylic acid; 3,4'-biphenyldicarboxylic acid; and ester-forming derivatives thereof.

[0182] The polyester may contain aliphatic dicarboxylic acids such as adipic acid, azelaic acid, and sebacic acid, and monocarboxylic acids such as benzoic acid, propionic acid, and butyric acid, as long as the object of the present invention is not impaired.

[0183] Examples of the aliphatic diol include ethylene glycol, 1,3-propylene diol, 1,4-butanediol, 1,4-cyclohexanedimethanol, 1,6-hexanediol, and ester-forming derivatives thereof.

[0184] For the polyester, monoalcohols such as butyl alcohol, hexyl alcohol, and octyl alcohol, and polyhydric alcohols such as trimethylolpropane, glycerin, and pentaerythritol may be used within the scope of the present invention.

[0185] The polyester can be synthesized by known methods such as direct esterification and transesterification. Examples of polycondensation catalysts used in the synthesis of polyester include known antimony compounds such as antimony trioxide and antimony pentoxide; germanium compounds such as germanium oxide; titanium compounds such as titanium acetate; and aluminum compounds such as aluminum chloride. However, the polycondensation catalyst is not limited to these.

[0186] Preferred polyesters include polyethylene terephthalate, polyethylene terephthalate-isophthalate copolymer, polyethylene-1,4-cyclohexanedimethylene-terephthalate copolymer, polyethylene-2,6-naphthalene dicarboxylate, polyethylene-2,6-naphthalene dicarboxylate-terephthalate copolymer, polyethylene-terephthalate-4,4'-biphenyldicarboxylate, poly-1,3-propylene-terephthalate, polybutylene terephthalate, polybutylene-2,6-naphthalene dicarboxylate, and the like.

[0187] More preferred polyesters include polyethylene terephthalate, polyethylene terephthalate-isophthalate copolymer, polyethylene-1,4-cyclohexanedimethylene-terephthalate copolymer, polybutylene terephthalate, and polyethylene-2,6-naphthalenedicarboxylate.

[0188] The content of the plasticizer is preferably in the range of 0 to 35% by mass, more preferably in the range of 5 to 30% by mass, based on the total mass of the resin as a film-forming component.

[0189] (2.1.4) Ultraviolet Absorber The resin layer may contain an ultraviolet absorber, if necessary. By containing an ultraviolet absorber, the resin layer can further improve the light absorptance in the ultraviolet region.

[0190] In the present invention, the term "ultraviolet absorber" refers to a compound that has the function of absorbing at least ultraviolet light having a wavelength of 400 nm or less. There are no particular limitations on the ultraviolet absorber as long as it has the above-mentioned absorption characteristics. In particular, the ultraviolet absorber used in the present invention is preferably a compound whose maximum absorption wavelength is in the range of 300 to 359 nm in the ultraviolet-visible light absorption spectrum in the wavelength region of 300 to 460 nm.

[0191] Examples of the ultraviolet absorber include triazine-based ultraviolet absorbers, benzotriazole-based ultraviolet absorbers, benzophenone-based ultraviolet absorbers, oxybenzophenone-based ultraviolet absorbers, salicylic acid ester-based ultraviolet absorbers, cyanoacrylate-based ultraviolet absorbers, etc. These may be contained alone or in combination of two or more.

[0192] Among these, triazine-based ultraviolet absorbers or benzotriazole-based ultraviolet absorbers are preferred, and triazine-based ultraviolet absorbers having two or less hydroxy groups per molecule or benzotriazole-based ultraviolet absorbers having one benzotriazole skeleton per molecule are also preferred.

[0193] These ultraviolet absorbers have good solubility in the resins mentioned above, and also have a high ability to absorb ultraviolet light at a wavelength of around 380 nm.

[0194] Examples of triazine-based ultraviolet absorbers having two or less hydroxy groups in one molecule include 2,4-bis-[{4-(4-ethylhexyloxy)-4-hydroxy}-phenyl]-6-(4-methoxyphenyl)-1,3,5-triazine ("Tinosorb (registered trademark) S" (BASF)), 2,4-bis[2-hydroxy-4-butoxyphenyl]-6-(2,4-dibutoxyphenyl)-1,3,5-triazine ("TINUVIN (registered trademark) 460" (BASF)), and a reaction product of 2-(4,6-bis(2,4-dimethylphenyl)-1,3,5-triazin-2-yl)-5-hydroxyphenyl with [(C10-C16 (mainly C12-C13) alkyloxy)methyl]oxirane ("TINUVIN (registered trademark) 400" (BASF)). BASF Corporation), 2-[4,6-bis(2,4-dimethylphenyl)-1,3,5-triazine-2-yl]-5-[3-(dodecyloxy)-2-hydroxypropoxy]phenol), reaction products of 2-(2,4-dihydroxyphenyl)-4,6-bis-(2,4-dimethylphenyl)-1,3,5-triazine and (2-ethylhexyl)-glycidic acid ester ("TINUVIN (registered trademark) 405" (BASF Corporation)), 2-(4,6-diphenyl-1,3,5-triazine-2-yl)-5-[(hexyl)oxy]phenol ("TINUVIN (registered trademark) 1577" (BASF Corporation)), 2-(4,6-diphenyl-1,3,5-triazine-2-yl)-5-[2-(2-ethylhexanoyloxy)ethoxy]phenol ("ADK STAB LA46 (manufactured by ADEKA Corporation)), 2-(2-hydroxy-4-[1-octyloxycarbonylethoxy]phenyl)-4,6-bis(4-phenylphenyl)-1,3,5-triazine ("TINUVIN (registered trademark) 479" (manufactured by BASF)), and 6,6',6''-(1,3,5-triazine-2,4,6-triyl)tris(3-hexyloxy-2-methylphenol) ("LA-F70" (manufactured by ADEKA Corporation)).

[0195] Furthermore, examples of benzotriazole-based ultraviolet absorbers having one benzotriazole skeleton per molecule include 2-(2H-benzotriazol-2-yl)-6-(1-methyl-1-phenylethyl)-4-(1,1,3,3-tetramethylbutyl)phenol ("TINUVIN (registered trademark) 928" (manufactured by BASF Corporation)), 2-(2-hydroxy-5-tert-butylphenyl)-2H-benzotriazole ("TINUVIN (registered trademark) PS" (BASF Corporation)), and BASF Corporation), ester compound of benzenepropanoic acid and 3-(2H-benzotriazol-2-yl)-5-(1,1-dimethylethyl)-4-hydroxy(C7-9 branched and linear alkyl) ("TINUVIN (registered trademark) 384-2" (BASF Corporation)), 2-(2H-benzotriazol-2-yl)-4,6-bis(1-methyl-1-phenylethyl)phenol ("TINUVIN (registered trademark) 900" (BASF Corporation)), methyl-3-(3-( 2-(2H-benzotriazol-2-yl)-5-t-butyl-4-hydroxyphenyl)propionate / polyethylene glycol 300 reaction product ("TINUVIN (registered trademark) 1130" (BASF Corporation)), 2-(2H-benzotriazol-2-yl)-p-cresol ("TINUVIN (registered trademark) P" (BASF Corporation)), 2-(2H-benzotriazol-2-yl)-4-6-bis(1-methyl-1-phenylethyl)phenol ("TIN TINUVIN (registered trademark) 234 (manufactured by BASF Corporation), 2-[5-chloro(2H)-benzotriazol-2-yl]-4-methyl-6-(tert-butyl)phenol ("TINUVIN (registered trademark) 326 (manufactured by BASF Corporation)), 2-(2H-benzotriazol-2-yl)-4,6-di-tert-pentylphenol ("TINUVIN (registered trademark) 328 (manufactured by BASF Corporation)), 2-(2H-benzotriazol-2-yl)-4-(1,1,3,3-(3-(2H-benzotriazol-2-yl)-5-tert-butyl-4-hydroxyphenyl)phenol ("TINUVIN (registered trademark) 329" (BASF Corporation)), reaction product of methyl 3-(3-(2H-benzotriazol-2-yl)-5-tert-butyl-4-hydroxyphenyl)propionate with polyethylene glycol 300 ("TINUVIN (registered trademark) 213" (BASF Corporation)), 2-(2H-benzotriazol-2-yl)-6-dodecyl-4-methylphenol ("TINUVIN (registered trademark) 571" (BASF Corporation) Examples of such benzotriazoles include 2-[2-hydroxy-3-(3,4,5,6-tetrahydrophthalimido-methyl)-5-methylphenyl]benzotriazole ("Sumisorb (registered trademark) 250" (Sumitomo Chemical Co., Ltd.)), 2-(2-hydroxy-3-tert-butyl-5-methylphenyl)-5-chlorobenzotriazole ("SeeSorb (registered trademark) 703" (Shipro Chemical Co., Ltd.), or "KEMISORB (registered trademark) 73" (Shipro Chemical Co., Ltd.)).

[0196] Further, the benzophenone-based ultraviolet absorbers (benzophenone-based compounds), oxybenzophenone-based ultraviolet absorbers (oxybenzophenone-based compounds), for example, 2,4-dihydroxybenzophenone, 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-methoxybenzophenone-5-sulfonic acid (anhydrous and trihydrate), 2-hydroxy-4-octyloxybenzophenone, 4-dodecyloxy-2-hydroxybenzophenone, 4-benzyloxy-2-hydroxybenzophenone, 2,2',4,4'-tetrahydroxybenzophenone, 2,2'-dihydroxy-4,4-dimethoxybenzophenone, 2,2',4,4'-tetrahydroxybenzophenone ("SeeSorb (registered trademark) 106" (manufactured by Shipro Chemical Co., Ltd.)), 2,2'-dihydroxy-4-methoxybenzophenone ("KEMISORB (registered trademark) 111" (manufactured by Chemipro Chemical Co., Ltd.)), and the like.

[0197] Examples of the salicylate ester-based ultraviolet absorbers (salicylate ester-based compounds) include phenyl-2-acryloyloxybenzoate, phenyl-2-acryloyloxy-3-methylbenzoate, phenyl-2-acryloyloxy-4-methylbenzoate, phenyl-2-acryloyloxy-5-methylbenzoate, phenyl-2-acryloyloxy-3-methoxybenzoate, phenyl-2-hydroxybenzoate, phenyl-2-hydroxy-3-methylbenzoate, phenyl-2-hydroxy-4-methylbenzoate, phenyl-2-hydroxy-5-methylbenzoate, phenyl-2-hydroxy-3-methoxybenzoate, 2,4-di-tert-butylphenyl-3,5-di-tert-butyl-4-hydroxybenzoate ("TINUVIN (registered trademark) 120" (manufactured by BASF)), and the like.

[0198] Examples of the cyanoacrylate ultraviolet absorber (cyanoacrylate compound) include alkyl-2-cyanoacrylate, cycloalkyl-2-cyanoacrylate, alkoxyalkyl-2-cyanoacrylate, alkenyl-2-cyanoacrylate, and alkynyl-2-cyanoacrylate.

[0199] The content of the ultraviolet absorber is preferably in the range of 0.1 to 8 mass %, more preferably in the range of 0.5 to 5 mass %, based on the total mass of the resin as a film-forming component.

[0200] By ensuring that the thickness is within the above range, the resin layer can improve its absorptivity in the ultraviolet region. As a result, the laminate protects the light-emitting element or light-emitting device in the display device from external light (ultraviolet rays), improving the light resistance of the display device when the laminate is attached. Furthermore, the quality of the display device can be maintained for a long period of time.

[0201] (2.1.5) Antioxidant The resin layer preferably contains an antioxidant. By containing an antioxidant, deterioration of the resin layer can be suppressed. Specifically, decomposition of the resin layer due to halogens from residual solvents, phosphoric acid from phosphoric acid-based plasticizers, etc. can be delayed or prevented. Furthermore, in the present invention, by using the above-mentioned dye compound and an antioxidant in combination, the light absorption waveform in the resin layer can be made sharper.

[0202] The antioxidant is not particularly limited, but is preferably a hindered phenol compound. Hindered phenol compounds have high affinity with the dye compounds. Their interaction sharpens the light absorption waveform, suppresses light absorption on the long wavelength side, and reduces light emission loss in the light-emitting element or light-emitting device.

[0203] Examples of hindered phenol antioxidants include 2,6-di-t-butyl-p-cresol, pentaerythrityl-tetrakis[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate], triethylene glycol-bis[3-(3-t-butyl-5-methyl-4-hydroxyphenyl)propionate], 1,6-hexanediol-bis[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate], 2,4-bis-(n-octylthio)-6-(4-hydroxy-3,5-di-t-butylanilino) -1,3,5-triazine, 2,2-thio-diethylenebis[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate], octadecyl-3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate, N,N'-hexamethylenebis(3,5-di-t-butyl-4-hydroxy-hydrocinnamamide), 1,3,5-trimethyl-2,4,6-tris(3,5-di-t-butyl-4-hydroxybenzyl)benzene, tris-(3,5-di-t-butyl-4-hydroxybenzyl)-isocyanurate, and the like.

[0204] Among these, 2,6-di-t-butyl-p-cresol, pentaerythrityl tetrakis[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate], or triethylene glycol bis[3-(3-t-butyl-5-methyl-4-hydroxyphenyl)propionate] is preferred. Furthermore, a hydrazine-based metal deactivator such as N,N'-bis[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionyl]hydrazine or a phosphorus-based processing stabilizer such as tris(2,4-di-t-butylphenyl)phosphite may also be used in combination.

[0205] The hindered phenol-based antioxidant may be a commercially available product, such as "Irganox (registered trademark) 1076" and "Irganox (registered trademark) 1010" (both manufactured by BASF Japan Ltd.).

[0206]

[0207] The content of the antioxidant is preferably 5% by mass or less, more preferably 2% by mass or less, and even more preferably in the range of 0.5 to 1% by mass, based on the total mass of the resin as a film-forming component.

[0208] (2.1.6) Fine Particles The resin layer preferably contains fine particles. By containing fine particles, light emission loss of the light emitting element or light emitting device can be reduced. In addition, slipperiness can be imparted to the resin layer.

[0209] The fine particles may be inorganic or organic compounds, examples of which include silicon dioxide, titanium dioxide, aluminum oxide, zirconium oxide, calcium carbonate, talc, clay, calcined kaolin, calcined calcium silicate, hydrated calcium silicate, aluminum silicate, magnesium silicate, and calcium phosphate.

[0210] Examples of organic compounds include polytetrafluoroethylene, cellulose acetate, polystyrene, polymethyl methacrylate, polypropyl methacrylate, polymethyl acrylate, polyethylene carbonate, styrene-acrylic resins, silicone resins, polycarbonate, benzoguanamine resins, melamine resins, polyolefins, polyesters, polyamides, polyimides, polyethylene fluoride, etc. Also included are pulverized fractions of organic polymer compounds such as starch.

[0211] Other examples of fine particles include polymer compounds synthesized by suspension polymerization, polymer compounds formed into spherical shapes by spray drying, dispersion methods, and inorganic compounds.

[0212] The average particle size of the primary particles of the fine particles is preferably in the range of 5 to 400 nm, and more preferably in the range of 10 to 300 nm.

[0213] The fine particles may be contained in the resin layer mainly as secondary aggregates having a particle size in the range of 0.05 to 0.3 μm. As long as the average particle size of the primary particles of the fine particles is in the range of 100 to 400 nm, the fine particles may be contained as primary particles without agglomeration.

[0214] From the viewpoint of reducing the turbidity of the resin layer, the fine particles preferably contain silicon, and particularly preferably contain silicon dioxide. Commercially available silicon dioxide fine particles include, for example, Aerosil (registered trademark) R972, R972V, R974, R812, 200, 200V, 300, R202, OX50, and TT600 (all manufactured by Nippon Aerosil Co., Ltd.).

[0215] Silicon-containing particles have a high affinity with the dye compound. By using silicon-containing particles in combination with the dye compound, the light absorption waveform in the resin layer can be made sharper. Furthermore, light absorption on the long wavelength side is suppressed, and the luminescence loss of the light-emitting element or light-emitting device can be reduced. Among the silicon-containing particles, the above-mentioned "Aerosil (registered trademark) R812 or R972" is particularly preferred. These highly hydrophobic particles have a high affinity with the dye compound, and their interaction can further reduce the luminescence loss of the light-emitting element or light-emitting device.

[0216] The content of the fine particles is preferably 10% by mass or less, more preferably 5% by mass or less, and even more preferably in the range of 0.5 to 2% by mass, based on the total mass of the resin as a film-forming component.

[0217] The addition of the fine particles is preferably carried out by in-line mixing. Examples of in-line mixers include static mixers. Examples of static mixers include a static in-pipe mixer "Hi-Mixer SWJ type" (manufactured by Toray Engineering Co., Ltd.).

[0218] (2.1.7) Other Additives The resin layer may further contain other additives, such as particles (e.g., rubber particles, metal oxide particles), fibers (e.g., acicular particles, cellulose nanofibers), antistatic agents, release agents, thickeners, etc., as needed.

[0219] (2.2) Method for Producing Resin Layer The method for producing the resin layer is not particularly limited, but is preferably a solution casting method or a melt casting method from the viewpoints of suppressing coloration, foreign matter defects, and optical defects such as die lines, etc. Among these, the solution casting method is preferred from the viewpoints of low temperatures during the processing step and the ability to add various additives.

[0220] In the solution casting method, a dope containing a resin, a solvent, and any other ingredients is prepared, and then the dope is cast onto a substrate and then dried to obtain a resin layer.

[0221] A method for producing a resin layer by a solution casting method will be described. In particular, when the resin as a film-forming component is cellulose ester, the following production method is preferably used. For other resins, conventionally known methods can be used.

[0222] In this specification, in the description of the method for producing a resin layer, the cast membrane is also referred to as a "web." Furthermore, the web from which the solvent has been removed to some extent by drying is also referred to as a "film."

[0223] (2.2.1) Dope Preparation Process The dope preparation process will be described. A higher concentration of the resin in the dope is preferable because it reduces the drying load after casting onto the metal support. However, if the cellulose ester concentration is too high, the load during filtration increases, resulting in poor filtration accuracy. A concentration that satisfies both of these requirements is preferably within the range of 10 to 35% by mass, and more preferably within the range of 15 to 25% by mass.

[0224] The solvent contained in the dope may be one kind alone or two or more kinds. From the viewpoint of production efficiency, it is preferable to use a mixture of a good solvent and a poor solvent for cellulose ester. Examples of the good solvent include methylene chloride and methyl acetate. Examples of the poor solvent include methanol, ethanol, n-butanol, cyclohexane, cyclohexanone, etc.

[0225] The dope preferably contains water in the range of 0.01 to 2% by mass. In the film-forming step described later, the solvent removed from the casting film by drying may be recovered and reused for dissolving the cellulose ester.

[0226] When preparing the dope, a general method can be used to dissolve the cellulose ester. By combining heating and pressure, the cellulose ester can be heated to a temperature above the boiling point at normal pressure. When preparing the dope, a general method can be used to dissolve or disperse the dye compound or the like.

[0227] Next, the cellulose ester solution is filtered using a suitable filter material such as filter paper, etc. The filter material preferably has an absolute filtration accuracy of 0.008 mm or less, more preferably in the range of 0.001 to 0.008 mm, and even more preferably in the range of 0.003 to 0.006 mm.

[0228] The filter material is not particularly limited, and a common filter material can be used. The filter material is preferably made of a plastic material such as polypropylene or Teflon (registered trademark), or a metal material such as stainless steel, in order to prevent fibers from falling off.

[0229] The dope can be filtered by a conventional method. For example, the filtration temperature is preferably equal to or higher than the boiling point of the solvent at normal pressure, and is within a range in which the solvent does not boil under pressure. By filtering while heating, the increase in the difference in filtration pressure (differential pressure) before and after filtration can be reduced. The filtration temperature is preferably within a range of 45 to 120°C, more preferably within a range of 45 to 70°C, and even more preferably within a range of 45 to 55°C.

[0230] The filtration pressure is preferably small, and is preferably 1.6 MPa or less, more preferably 1.2 MPa or less, and even more preferably 1.0 MPa or less.

[0231] (2.2.2) Step of casting the dope onto a support to form a cast film Next, the casting of the dope will be described.

[0232] The metal support used in the casting step preferably has a mirror-finished surface. Examples of the metal support include a stainless steel belt or a cast drum with a plated surface. The casting width is preferably within the range of 1 to 4 m.

[0233] The surface temperature of the metal support in the casting step is preferably -50°C or higher and lower than the boiling point of the solvent, more preferably in the range of 0 to 40°C, and even more preferably in the range of 5 to 30°C.

[0234] In order to ensure good planarity of the resin layer, the residual solvent content when the casting film (web) is peeled from the metal support is preferably in the range of 10 to 150% by mass, more preferably in the range of 20 to 40% by mass or in the range of 60 to 130% by mass, and further preferably in the range of 20 to 30% by mass or in the range of 70 to 120% by mass.

[0235] In the present invention, the amount of residual solvent is defined by the following formula.

[0236] Residual solvent amount (mass%) = {(M - N) / N} × 100, where M is the mass of a sample taken at any time during or after the production of the web or film, and N is the mass of M after heating at 115°C for 1 hour.

[0237] (2.2.3) Step of Peeling the Cast Film from the Support The cast film (web) is peeled from the metal support. As a method for peeling the web from the metal support, a known method can be used.

[0238] (2.2.4) Step of drying the cast film In the step of drying the resin layer, the cast film (web) peeled from the metal support is further dried. The residual solvent content is preferably 1% by mass or less, more preferably 0.1% by mass or less, and further preferably in the range of 0 to 0.01% by mass.

[0239] In the web drying process, roll drying or tenter drying, in which the web is transported while being dried, is generally used. In the roll drying method, the web is dried by passing it alternately through multiple rolls arranged above and below.

[0240] The web is preferably stretched in the machine direction (MD) immediately after peeling from the metal support, at a portion of the web where the residual solvent is high, and is also preferably stretched in the transverse direction (TD) using a tenter system in which both ends of the web are held with clips or the like.

[0241] The means for drying the web is not particularly limited, and generally includes hot air, infrared rays, a heated roll, microwaves, etc. From the viewpoint of simplicity, hot air is preferred.

[0242] The drying temperature in the web drying step is preferably in the range of 90 to 200° C., more preferably in the range of 110 to 190° C. The drying temperature is preferably increased stepwise.

[0243] The preferred drying time, although it depends on the drying temperature, is preferably within the range of 5 to 60 minutes, and more preferably within the range of 10 to 30 minutes.

[0244] The thickness of the film is not particularly limited, but is preferably in the range of 10 to 200 μm, more preferably in the range of 10 to 100 μm, and more preferably in the range of 20 to 60 μm.

[0245] The width of the film is preferably in the range of 1 to 4 m. From the viewpoint of productivity, the width is preferably in the range of 1.6 to 4 m, and more preferably in the range of 1.8 to 3.6 m.

[0246] (2.2.5) Step of Stretching the Film The stretching operation can be performed sequentially or simultaneously in the longitudinal direction (MD) and width direction (TD) of the film. The final stretching ratios in the two mutually perpendicular axial directions are preferably within the range of 1.0 to 2.0 times in the MD direction and 1.07 to 2.0 times in the TD direction. Furthermore, the ranges of 1.0 to 1.5 times in the MD direction and 1.07 to 2.0 times in the TD direction are also preferred.

[0247] For example, a method of stretching in the MD direction by using the difference in peripheral speeds between multiple rolls can be used. Other examples include a method of fixing both ends of the web with clips or pins, widening the gap between the clips or pins in the direction of travel to stretch in the MD direction, and a method of similarly widening the web laterally to stretch in the TD direction. Another example includes a method of simultaneously widening the web in both the MD and TD directions to stretch in both the MD and TD directions.

[0248] In the film-forming process, the width is preferably maintained or the film is stretched in the width direction by a tenter, and either a pin tenter or a clip tenter may be used.

[0249] The film transport tension in the film-forming process in a tenter or the like is preferably within a range of 120 to 200 N / m, more preferably within a range of 140 to 200 N / m, and even more preferably within a range of 140 to 160 N / m, although this varies depending on the temperature.

[0250] When the glass transition temperature of the film is Tg, the temperature of the film during stretching is preferably within the range of (Tg-30) to (Tg+100)°C, more preferably within the range of (Tg-20) to (Tg+80)°C, and even more preferably within the range of (Tg-5) to (Tg+20)°C.

[0251] The Tg of the film can be controlled by the types of materials constituting the film and the ratio of the materials constituting the film. The Tg of the film when dry is preferably 110° C. or higher, and more preferably 120° C. or higher.

[0252] The dry Tg of the film is preferably 190° C. or less, and more preferably 170° C. or less. The Tg of the film can be determined by the method described in JIS K7121 or the like.

[0253] By stretching the film at a temperature of 150°C or higher and a stretch ratio of 1.15 or higher, it is possible to impart an appropriate degree of roughness to the film surface. By imparting an appropriate degree of roughness to the film surface, not only can the slipperiness be improved, but also the surface processability and adhesion to adjacent layers can be improved. The average surface roughness Ra of the film is preferably in the range of 2.0 to 4.0 nm, and more preferably in the range of 2.5 to 3.5 nm.

[0254] It is preferable that the average surface roughness Ra (nm) of the film and the polarity of the film itself with respect to the solvent satisfy the following relational expression.

[0255] (Formula) Ra≧3.5×logP−25.4 After stretching, the film is preferably heat-set. The temperature during heat-setting is preferably higher than the temperature at which the film was last stretched in the TD direction. Heat-setting is preferably carried out at a temperature of (Tg−20°C) or lower, usually for 0.5 to 300 seconds. In this case, heat-setting is preferably carried out while sequentially increasing the temperature in two or more divided regions so that the temperature difference is in the range of 1 to 100°C.

[0256] The heat-set film is usually cooled to below Tg, and the clipped portions at both ends of the film are cut and wound up. At this time, it is preferable to relax the film by 0.1 to 10% in the TD or MD direction at a temperature below the final heat-setting temperature and above Tg.

[0257] The cooling is preferably performed by slowly cooling from the final heat setting temperature to Tg at a cooling rate of 100°C per second or less. The method for cooling and relaxation treatment is not particularly limited, and any conventionally known method can be used. From the viewpoint of improving the dimensional stability of the film, it is preferable to perform these treatments while sequentially cooling in multiple temperature ranges.

[0258] The cooling rate is calculated by (T1-Tg) / t, where T1 is the final heat setting temperature and t is the time it takes for the film to reach Tg from the final heat setting temperature.

[0259] The optimum conditions for these heat setting conditions and cooling and relaxation treatment conditions vary depending on the types of additives such as cellulose ester, dye compound, etc. that constitute the film (resin layer). The physical properties of the obtained biaxially stretched film can be measured, and the constituent materials of the optical film can be appropriately selected so that the optical film has desirable properties.

[0260] (2.3) Physical Properties of Resin Layer (2.3.1) Average Light Transmittance The first resin layer has an average light transmittance of 87% or more in the wavelength region of 450 to 800 nm. By keeping the average light transmittance within this range, it is possible to prevent the light emitted from the light-emitting element in the display device from being absorbed by the resin layer, thereby increasing the amount of visible light emission. In other words, it is possible to reduce light emission loss.

[0261] The first resin preferably absorbs ultraviolet light more effectively and transmits visible light more effectively, i.e., it preferably has a lower average light transmittance in the ultraviolet region and a higher average light transmittance in the wavelength region of 450 to 800 nm.

[0262] The light absorption characteristics of the second resin layer are not particularly limited, but from the viewpoint of further reducing light emission loss, it is preferable that the second resin layer have a high transmittance for visible light.

[0263] The light transmittance of the resin layer can be adjusted by incorporating the above-mentioned dye compound.

[0264] The average light transmittance in the wavelength region of 450 to 800 nm (visible light region) can be measured by the following method. The resin layer is conditioned for 24 hours in an air-conditioned room at a temperature of 23°C and a relative humidity of 55 RH. Then, in accordance with JIS K-7375:2008, the light transmittance is measured using an ultraviolet-visible spectrophotometer (for example, "UV-2450" (manufactured by Shimadzu Corporation)), and the arithmetic average value is calculated in the wavelength region of 450 to 800 nm.

[0265] (2.3.2) Storage Modulus The first resin layer has a storage modulus at 25°C in the range of 4.0 to 8.0 GPa. This makes the first resin layer relatively soft, improving the flexibility of the laminate. Furthermore, the ratio of the storage modulus at 25°C of the second resin layer to that of the first resin layer is in the range of 0.7 to 1.5. In other words, the storage modulus of the first resin layer and the storage modulus of the second resin layer are approximately the same, further improving the flexibility of the laminate.

[0266] The storage modulus of the resin layer at 25° C. can be adjusted by appropriately selecting the type and content of materials (resin, rubber particles, plasticizer, etc.) and also by the conditions for producing the resin layer.

[0267] The storage modulus of the resin layer at 25°C can be measured using a rheometer "RSA-3" (manufactured by TA Instruments Japan Co., Ltd.) under the following test conditions. Test conditions (dynamic viscoelasticity test) Testing machine: Dynamic viscoelasticity measuring device "RSA-3" (manufactured by TA Instruments Japan Co., Ltd.) Deformation method: Tension Preload: 55 g Temperature range: -70 to 200°C Frequency: 1.0 Hz Displacement: ±0.1% Sample: Width 5 mm Chuck distance: 20 mm

[0268] (2.3.3) Thickness From the viewpoint of thinning the laminate of the present invention, the thickness of the resin layer is preferably in the range of 10 to 60 μm, more preferably in the range of 15 to 50 μm, and even more preferably in the range of 20 to 40 μm. By thinning the laminate, flexibility can be improved.

[0269] From the viewpoint of impact resistance, the glass transition temperature of the resin layer is preferably within the range of −30 to 180° C. When a plurality of glass transition temperatures are observed when measuring the glass transition temperature of the resin layer, the lowest observed glass transition temperature is taken as the glass transition temperature of the resin layer.

[0270] The glass transition temperature (Tg) can be measured in accordance with JIS K 7121 (2012) using a DSC (Differential Scanning Calorimetry).

[0271] (3) Adhesive Layer The laminate of the present invention has an adhesive layer, which allows the layers to adhere to each other and form a laminate.

[0272] In the present invention, the "adhesive layer" refers to a layer having sufficient adhesiveness to attach the laminate to a display device or to bond the layers in the laminate together. The adhesive layer is preferably made of an adhesive.

[0273] The first adhesive layer and the second and third adhesive layers, which are provided as needed, may be made of the same material and have the same physical properties, or may be made of different materials and have different physical properties.

[0274] The adhesive layer may be in the form of a film that can be wound up, or in the form of a coating layer, which is formed by applying an adhesive onto an adjacent layer and then curing the applied adhesive.

[0275] The pressure-sensitive adhesive is not particularly limited, and examples thereof include rubber-based pressure-sensitive adhesives, acrylic pressure-sensitive adhesives, silicone-based pressure-sensitive adhesives, urethane-based pressure-sensitive adhesives, vinyl alkyl ether-based pressure-sensitive adhesives, polyvinyl alcohol-based pressure-sensitive adhesives, polyvinylpyrrolidone-based pressure-sensitive adhesives, polyacrylamide-based pressure-sensitive adhesives, and cellulose-based pressure-sensitive adhesives. Among these, acrylic pressure-sensitive adhesives are preferred. Acrylic pressure-sensitive adhesives have excellent transparency and excellent adhesive properties (adhesion, cohesion, and adhesion). They also have excellent weather resistance, heat resistance, and the like. Here, "acrylic pressure-sensitive adhesive" refers to a pressure-sensitive adhesive containing an acrylic resin as a main component.

[0276] (3.1) Constituent material of adhesive layer (ultraviolet-curable acrylic adhesive) The adhesive layer made of an acrylic adhesive is preferably a layer formed by, for example, ultraviolet curing (ultraviolet polymerization) of an ultraviolet-curable acrylic adhesive. Note that, by ultraviolet curing (ultraviolet polymerization) of an ultraviolet-curable acrylic adhesive, a (meth)acrylic resin is produced.

[0277] The "ultraviolet-curable acrylic adhesive" preferably contains a monomer component containing alkyl (meth)acrylate or a partial polymer of the monomer component, a photopolymerization initiator, and the like.

[0278] (3.1.1) Monomer Component The UV-curable acrylic adhesive is primarily composed of a (meth)acrylic resin obtained by UV-curing (UV-polymerizing) an acrylate-containing monomer component or a partial polymer of the monomer component. Below, we will explain the alkyl (meth)acrylate contained in the monomer component and other monomers that may be contained. The other monomers that may be contained are preferably monofunctional monomers, but may also be polyfunctional monomers.

[0279] (3.1.1.1) Alkyl (meth)acrylate In this specification, "(meth)acrylic" refers to acrylic and methacrylic, and is a general term for both. Furthermore, "alkyl (meth)acrylate" refers to alkyl acrylate and alkyl methacrylate, and is a general term for both. The alkyl (meth)acrylate in the adhesive layer is preferably an alkyl (meth)acrylate having a linear or branched alkyl group having 1 to 24 carbon atoms at the ester terminal. These may be contained alone or in combination of two or more.

[0280] Examples of alkyl(meth)acrylates include alkyl(meth)acrylates having a branched alkyl group having 4 to 9 carbon atoms. Examples of alkyl(meth)acrylates include n-butyl(meth)acrylate, sec-butyl(meth)acrylate, tert-butyl(meth)acrylate, isobutyl(meth)acrylate, n-pentyl(meth)acrylate, isopentyl(meth)acrylate, isohexyl(meth)acrylate, isoheptyl(meth)acrylate, 2-ethylhexyl(meth)acrylate, isooctyl(meth)acrylate, and isononyl(meth)acrylate. These may be contained alone or in combination of two or more.

[0281] The content of the alkyl(meth)acrylate having an alkyl group having 1 to 24 carbon atoms at the ester terminal is preferably 40% by mass or more, more preferably 50% by mass or more, and even more preferably 60% by mass or more, based on the total mass of the monomer components.

[0282] (3.1.1.2) Other Monomer Components Examples of monofunctional copolymerizable monomers (monofunctional monomers) other than alkyl (meth)acrylates include cyclic nitrogen-containing monomers. The cyclic nitrogen-containing monomer is not particularly limited as long as it has a polymerizable functional group with an unsaturated double bond, such as a (meth)acryloyl group or a vinyl group, and has a cyclic nitrogen structure. The cyclic nitrogen structure preferably has a nitrogen atom within the cyclic structure.

[0283] Examples of cyclic nitrogen-containing monomers include lactam vinyl monomers such as N-vinyl-2-pyrrolidone, N-vinyl-ε-caprolactam, and methylvinylpyrrolidone; and vinyl monomers having a nitrogen-containing heterocycle such as vinylpyridine, vinylpiperidone, vinylpyrimidine, vinylpiperazine, vinylpyrazine, vinylpyrrole, vinylimidazole, vinyloxazole, and vinylmorpholine. Also included are (meth)acrylic monomers containing a heterocycle such as a morpholine ring, piperidine ring, pyrrolidine ring, and piperazine ring. Specific examples include N-acryloylmorpholine, N-acryloylpiperidine, N-methacryloylpiperidine, and N-acryloylpyrrolidine. Among these, lactam vinyl monomers are preferred.

[0284] The content of the cyclic nitrogen-containing monomer is preferably 0.5 to 50 mass %, more preferably 0.5 to 40 mass %, and even more preferably 0.5 to 30 mass %, based on the total mass of the monomer components.

[0285] The monofunctional monomer may be a hydroxyl group-containing monomer, which is not particularly limited as long as it has a polymerizable functional group with an unsaturated double bond, such as a (meth)acryloyl group or a vinyl group, and also has a hydroxyl group.

[0286] Examples of hydroxy group-containing monomers include hydroxyalkyl (meth)acrylates such as 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, 6-hydroxyhexyl (meth)acrylate, 8-hydroxyoctyl (meth)acrylate, 10-hydroxydecyl (meth)acrylate, and 12-hydroxylauryl (meth)acrylate; and hydroxyalkyl cycloalkane (meth)acrylates such as (4-hydroxymethylcyclohexyl)methyl (meth)acrylate. Other examples include hydroxyethyl (meth)acrylamide, allyl alcohol, 2-hydroxyethyl vinyl ether, 4-hydroxybutyl vinyl ether, and diethylene glycol monovinyl ether. Among these, hydroxyalkyl (meth)acrylates are preferred. These may be used alone or in combination.

[0287] The content of the hydroxy group-containing monomer is preferably within a range of 1 to 30% by mass, more preferably within a range of 2 to 27% by mass, and even more preferably within a range of 3 to 25% by mass, based on the total mass of the monomer components. By keeping the content within the above range, a decrease in the adhesive strength of the pressure-sensitive adhesive layer can be suppressed. Furthermore, an increase in viscosity and gelation of the resulting pressure-sensitive adhesive can be suppressed.

[0288] Other examples of the monofunctional monomer include a carboxy group-containing monomer and a monomer having a cyclic ether group.

[0289] The carboxyl group-containing monomer is not particularly limited as long as it has a polymerizable functional group with an unsaturated double bond, such as a (meth)acryloyl group or a vinyl group, and also has a carboxyl group.

[0290] Examples of carboxy group-containing monomers include (meth)acrylic acid, carboxyethyl (meth)acrylate, carboxypentyl (meth)acrylate, itaconic acid, maleic acid, fumaric acid, crotonic acid, and isocrotonic acid. Itaconic acid or maleic acid may also be an anhydride thereof. Among these, the carboxy group-containing monomer is preferably acrylic acid or methacrylic acid, and more preferably acrylic acid. These may be contained alone or in combination of two or more.

[0291] The monomer having a cyclic ether group is not particularly limited as long as it has a polymerizable functional group having an unsaturated double bond, such as a (meth)acryloyl group or a vinyl group, and a cyclic ether group, such as an epoxy group or an oxetane group.

[0292] Examples of epoxy group-containing monomers include glycidyl (meth)acrylate, 3,4-epoxycyclohexylmethyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate glycidyl ether, etc. Examples of oxetane group-containing monomers include 3-oxetanylmethyl (meth)acrylate, 3-methyl-oxetanylmethyl (meth)acrylate, 3-ethyl-oxetanylmethyl (meth)acrylate, 3-butyl-oxetanylmethyl (meth)acrylate, 3-hexyl-oxetanylmethyl (meth)acrylate, etc. These may be contained alone or in combination of two or more.

[0293] The content of the carboxy group-containing monomer or the monomer having a cyclic ether group is preferably 30% by mass or less, more preferably 27% by mass or less, and even more preferably 25% by mass or less, based on the total mass of the monomer components.

[0294] Other monofunctional monomers include, for example, CH ２ = C(R １ ) COOR ２ Examples of the alkyl (meth)acrylate include alkyl (meth)acrylates represented by the formula: １ represents a hydrogen atom or a methyl group, R ２represents a substituted alkyl group having 1 to 3 carbon atoms or a cyclic cycloalkyl group.

[0295] The above CH ２ = C(R １ ) COOR ２ Examples of the alkyl(meth)acrylate represented by the formula (I) include phenoxyethyl(meth)acrylate, benzyl(meth)acrylate, cyclohexyl(meth)acrylate, 3,3,5-trimethylcyclohexyl(meth)acrylate, isobornyl(meth)acrylate, etc. These may be contained alone or in combination of two or more.

[0296] The above CH ２ = C(R １ ) COOR ２ The content of the alkyl (meth)acrylate represented by the formula (I) is preferably 50% by mass or less, more preferably 45% by mass or less, and even more preferably 40% by mass or less, based on the total mass of the monomer components.

[0297] Other monofunctional monomers include, for example, vinyl acetate, vinyl propionate, styrene, α-methylstyrene; glycol-based acrylate monomers such as polyethylene glycol (meth)acrylate, polypropylene glycol (meth)acrylate, methoxyethylene glycol (meth)acrylate, and methoxypolypropylene glycol (meth)acrylate; acrylate monomers such as tetrahydrofurfuryl (meth)acrylate, fluorine (meth)acrylate, silicone (meth)acrylate, and 2-methoxyethyl acrylate; amide group-containing monomers, amino group-containing monomers, imide group-containing monomers, N-acryloylmorpholine, and vinyl ether monomers. Also included are monomers having a cyclic structure such as terpene (meth)acrylate and dicyclopentanyl (meth)acrylate.

[0298] Further, other monofunctional monomers include silane-based monomers containing a silicon atom, such as 3-acryloxypropyltriethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, 4-vinylbutyltrimethoxysilane, 4-vinylbutyltriethoxysilane, 8-vinyloctyltrimethoxysilane, 8-vinyloctyltriethoxysilane, 10-methacryloyloxydecyltrimethoxysilane, 10-acryloyloxydecyltrimethoxysilane, 10-methacryloyloxydecyltriethoxysilane, and 10-acryloyloxydecyltriethoxysilane.

[0299] As the other monomer, in addition to the monofunctional monomers exemplified above, a polyfunctional monomer may be contained as necessary from the viewpoint of adjusting the cohesive strength of the adhesive layer.

[0300] The polyfunctional monomer is not particularly limited as long as it is a monomer having at least two polymerizable functional groups having an unsaturated double bond, such as a (meth)acryloyl group or a vinyl group.

[0301] Examples of the polyfunctional monomer include ester compounds of polyhydric alcohols and (meth)acrylic acid, such as (poly)ethylene glycol di(meth)acrylate, (poly)propylene glycol di(meth)acrylate, neopentyl glycol di(meth)acrylate, pentaerythritol di(meth)acrylate, pentaerythritol tri(meth)acrylate, dipentaerythritol hexa(meth)acrylate, 1,2-ethylene glycol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, 1,12-dodecanediol di(meth)acrylate, trimethylolpropane tri(meth)acrylate, and tetramethylolmethane tri(meth)acrylate; allyl (meth)acrylate, vinyl (meth)acrylate, divinylbenzene, epoxy acrylate, polyester acrylate, urethane acrylate, butyl di(meth)acrylate, and hexyl di(meth)acrylate.

[0302] Among these, trimethylolpropane tri(meth)acrylate, hexanediol di(meth)acrylate, or dipentaerythritol hexa(meth)acrylate is preferred. These may be contained alone or in combination of two or more.

[0303] The content of the polyfunctional monomer varies depending on the molecular weight, the number of functional groups, etc., but is preferably 3% by mass or less, more preferably 2% by mass or less, and even more preferably 1% by mass or less, based on the total mass of the monofunctional monomer. Furthermore, the content of the polyfunctional monomer is preferably 0.001% by mass or more. By being within the above range, the adhesive strength of the adhesive layer can be improved.

[0304] The monomer component may contain a partial polymer of the above-mentioned monomer component.

[0305] (3.1.2) Photopolymerization initiator The ultraviolet-curable acrylic pressure-sensitive adhesive according to the present invention preferably contains a photopolymerization initiator. By containing the photopolymerization initiator, the monomer component can be sufficiently polymerized.

[0306] The photopolymerization initiator is not particularly limited as long as it generates radicals when exposed to ultraviolet light and initiates photopolymerization, and commonly used photopolymerization initiators can be suitably used. Examples include benzoin ether-based photopolymerization initiators, acetophenone-based photopolymerization initiators, α-ketol-based photopolymerization initiators, photoactive oxime-based photopolymerization initiators, benzoin-based photopolymerization initiators, benzyl-based photopolymerization initiators, benzophenone-based photopolymerization initiators, ketal-based photopolymerization initiators, thioxanthone-based photopolymerization initiators, and acylphosphine oxide-based photopolymerization initiators.

[0307] Other examples include bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide (commercially available products include, for example, "Omnirad (registered trademark) 819" (manufactured by IGM Resins B.V.)) and 2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide (commercially available products include, for example, "Omnirad (registered trademark) TPO H" (manufactured by IGM Resins B.V.)). These may be contained alone or in combination of two or more.

[0308] The content of the photopolymerization initiator is preferably in the range of 0.005 to 0.5% by mass, more preferably 0.02 to 0.1% by mass, based on the total mass of the monomer components. By being in this range, ultraviolet curing (ultraviolet polymerization) can be sufficiently promoted.

[0309] (3.1.3) Others The ultraviolet-curable acrylic pressure-sensitive adhesive according to the present invention may further contain a silane coupling agent, a crosslinking agent, and the like.

[0310] Examples of the silane coupling agent include epoxy group-containing silane coupling agents such as 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, and 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane; amino group-containing silane coupling agents such as 3-aminopropyltrimethoxysilane, N-2-(aminoethyl)-3-aminopropylmethyldimethoxysilane, 3-triethoxysilyl-N-(1,3-dimethylbutylidene)propylamine, and N-phenyl-γ-aminopropyltrimethoxysilane; (meth)acrylic group-containing silane coupling agents such as 3-acryloxypropyltrimethoxysilane and 3-methacryloxypropyltriethoxysilane; and isocyanate group-containing silane coupling agents such as 3-isocyanatepropyltriethoxysilane.

[0311] The content of the silane coupling agent is preferably 1% by mass or less, more preferably in the range of 0.01 to 1% by mass, and even more preferably in the range of 0.02 to 0.6% by mass, based on the total mass of the monomer components.

[0312] Examples of crosslinking agents include isocyanate-based crosslinking agents, epoxy-based crosslinking agents, silicone-based crosslinking agents, oxazoline-based crosslinking agents, aziridine-based crosslinking agents, silane-based crosslinking agents, alkyl etherified melamine-based crosslinking agents, metal chelate-based crosslinking agents, and peroxide-based crosslinking agents. Among these, isocyanate-based crosslinking agents are preferred. These may be contained alone or in combination of two or more.

[0313] An isocyanate crosslinking agent is a compound having two or more isocyanate groups (including isocyanate regenerating functional groups in which the isocyanate groups are temporarily protected by a blocking agent or by polymerization, etc.) per molecule. Examples of the isocyanate crosslinking agent include aromatic isocyanates such as tolylene diisocyanate and xylene diisocyanate; alicyclic isocyanates such as isophorone diisocyanate; and aliphatic isocyanates such as hexamethylene diisocyanate.

[0314] The content of the crosslinking agent is preferably 5% by mass or less, more preferably in the range of 0.01 to 5% by mass, even more preferably in the range of 0.01 to 4% by mass, and particularly preferably in the range of 0.02 to 3% by mass, relative to the total mass of the monomer components.

[0315] In addition to the above components, the UV-curable acrylic adhesive may contain other additives as appropriate depending on the application. Examples of such additives include tackifiers; fillers such as hollow glass balloons; plasticizers; antioxidants; antioxidants, etc. The tackifier refers to a substance that is solid, semi-solid, or liquid at room temperature, such as a rosin derivative resin, a terpene resin, a petroleum resin, or an oil-soluble phenolic resin.

[0316] The viscosity of the UV-curable acrylic adhesive is preferably adjusted to a level suitable for application. The viscosity can be adjusted, for example, by adding various resins such as thickening additives, polyfunctional monomers, or the like, or by partially polymerizing the monomer components in the UV-curable acrylic adhesive. Note that the partial polymerization may be carried out before or after adding various polymers such as thickening additives, polyfunctional monomers, or the like.

[0317] The viscosity of an ultraviolet-curable acrylic adhesive varies depending on the content of additives, etc. Therefore, the polymerization rate when the monomer components in an ultraviolet-curable acrylic adhesive are partially polymerized cannot be uniquely determined. However, as a guideline, the polymerization rate is preferably 20% or less, more preferably in the range of 3 to 20%, and even more preferably in the range of 5 to 15%. Furthermore, by keeping the polymerization rate 20% or less, the viscosity can be adjusted to be suitable for application work.

[0318] (3.2) Method for Producing an Adhesive Layer An adhesive layer can be produced by applying an ultraviolet-curable acrylic adhesive onto an adjacent layer and curing it with ultraviolet light (ultraviolet polymerization) through irradiation with ultraviolet light. Alternatively, a film-like adhesive layer can be produced by applying an ultraviolet-curable acrylic adhesive onto a substrate and curing it with ultraviolet light through irradiation with ultraviolet light (ultraviolet polymerization).

[0319] The substrate is not particularly limited, and examples thereof include a release film and a transparent resin film.

[0320] Examples of the release film include release resin films such as polyethylene, polypropylene, polyethylene terephthalate, and polyester films, porous materials such as paper, cloth, and nonwoven fabric, and thin sheets such as nets, foam sheets, metal foils, and laminates thereof. Among these, resin films are preferred from the viewpoint of excellent surface smoothness.

[0321] Examples of release resin films include polyethylene films, polypropylene films, polybutene films, polybutadiene films, polymethylpentene films, polyvinyl chloride films, vinyl chloride copolymer films, polyethylene terephthalate films, polybutylene terephthalate films, polyurethane films, and ethylene-vinyl acetate copolymer films.

[0322] The thickness of the release film is preferably in the range of 5 to 200 μm, and more preferably in the range of 5 to 100 μm.

[0323] The release film is preferably subjected to a release treatment using a silicone-based, fluorine-based, long-chain alkyl-based, or fatty acid amide-based release agent as needed. It is also preferable to perform an antifouling treatment using silica powder or the like. Other antistatic treatments such as coating, kneading, and vapor deposition may also be performed. In particular, release treatment using a silicone-based, fluorine-based, or long-chain alkyl-based release agent makes it easier to peel off the film-like adhesive layer.

[0324] The transparent resin film is not particularly limited, but is preferably transparent and composed of a single layer. Examples of transparent resin films include polyesters such as polyethylene terephthalate and polyethylene naphthalate, acetate resins, polyethersulfone, polycarbonate, polyamide, polyimide, polyolefin, (meth)acrylic resins, polyvinyl chloride, polyvinylidene chloride, polystyrene, polyvinyl alcohol, polyarylate, and polyphenylene sulfide. Among these, polyester, polyimide, or polyethersulfone is preferred.

[0325] The thickness of the transparent resin film is preferably in the range of 2 to 200 μm, and more preferably in the range of 20 to 188 μm.

[0326] The method for applying the ultraviolet-curable acrylic pressure-sensitive adhesive is not particularly limited, and any conventionally known method can be used, including roll coating, kiss roll coating, gravure coating, reverse coating, roll brushing, spray coating, dip roll coating, bar coating, knife coating, air knife coating, curtain coating, lip coating, and die coating.

[0327] The illuminance of the ultraviolet light irradiated onto the ultraviolet-curing acrylic adhesive is 5 to 200 mW / cm ２ It is preferable that the irradiance of the ultraviolet light is within the range of 5 mW / cm. ２ By setting the irradiance of the ultraviolet light to 200 mW / cm or more, the polymerization reaction time can be shortened, and productivity is excellent. ２By keeping the cumulative dose of ultraviolet light at 100 to 5000 mJ / cm or less, rapid consumption of the photopolymerization initiator can be suppressed. As a result, polymerization proceeds sufficiently, and a high-molecular-weight polymer ((meth)acrylic resin) is obtained. This allows an adhesive layer with excellent holding power, especially at high temperatures. The cumulative dose of ultraviolet light is 100 to 5000 mJ / cm. ２ It is preferable that the range is within the range of

[0328] The ultraviolet lamp used in the present invention is not particularly limited, but is preferably an LED lamp. LED lamps emit less heat than other ultraviolet lamps, and therefore can suppress temperature increases during ultraviolet curing of ultraviolet-curable acrylic adhesives. This allows for the production of high-molecular-weight polymers, resulting in adhesive layers with sufficient cohesive strength, and enhancing the holding power of adhesive sheets at high temperatures. Multiple ultraviolet lamps may be used in combination. Furthermore, the irradiation method may involve intermittent irradiation of ultraviolet light, with a light period during which ultraviolet light is irradiated and a dark period during which ultraviolet light is not irradiated.

[0329] The final polymerization rate of the monomer components in the ultraviolet-curable acrylic pressure-sensitive adhesive is preferably 90% or more, more preferably 95% or more, and even more preferably 98% or more.

[0330] The peak wavelength of the ultraviolet light irradiated onto the ultraviolet-curable acrylic adhesive is preferably within the range of 200 to 500 nm, more preferably within the range of 300 to 450 nm. When the peak wavelength of the ultraviolet light is 500 nm or less, the photopolymerization initiator decomposes and the polymerization reaction begins. Furthermore, when the peak wavelength of the ultraviolet light is 200 nm or more, scission of the polymer chain can be suppressed, and sufficient adhesiveness can be obtained.

[0331] Since the polymerization reaction is easily inhibited by oxygen in the air, it is preferable to block oxygen. Examples of methods for blocking oxygen include forming a release film on the coating layer of the ultraviolet-curable acrylic pressure-sensitive adhesive, or performing the polymerization reaction in a nitrogen atmosphere. Examples of the release film include the release films described above.

[0332] (3.3) Physical Properties of Adhesive Layer From the viewpoint of making the final laminate thinner, the thickness of the adhesive layer is preferably in the range of 2 to 60 μm, more preferably in the range of 2 to 20 μm, and even more preferably in the range of 5 to 15 μm.

[0333] The weight average molecular weight (Mw) of the resin material (e.g., (meth)acrylic resin) used in the adhesive layer is preferably in the range of 100,000 to 5,000,000, and more preferably in the range of 200,000 to 1,000,000, from the viewpoint of controlling the storage modulus.

[0334] The weight average molecular weight (Mw) of the resin material used in the adhesive layer is preferably smaller than the weight average molecular weight (Mw) of the resin material used in the optical film, thereby enabling the effects of the present invention to be obtained more efficiently.

[0335] The weight average molecular weight (Mw) of the resin material can be measured using a gel permeation chromatograph "HLC8220GPC" (manufactured by Tosoh Corporation) and columns "TSK-GEL G6000," "HXL-G5000," "HXL-G5000," "HXL-G4000," and "HXL-G3000HXL" (all manufactured by Tosoh Corporation, in series). 20 mg ± 0.5 mg of sample was dissolved in 10 mL of tetrahydrofuran and filtered through a 0.45 mm filter. 100 mL of this solution was then injected into the column (temperature 40°C) and measured using an RI detector at 40°C, with the value converted to styrene equivalent.

[0336] The glass transition temperature (Tg) of the adhesive layer is preferably 0°C or lower, more preferably -10°C or lower, and even more preferably -20°C or lower, from the viewpoint of achieving both impact resistance in a low-temperature environment and contrast after bending.

[0337] The glass transition temperature (Tg) can be measured in accordance with JIS K 7121 (2012) using a DSC (Differential Scanning Calorimetry).

[0338] (3.4) Bezel in Second Adhesive Layer The second adhesive layer may have a bezel. In the present invention, the term "bezel" refers to a region that has an extremely low transmittance of visible light and is formed in a frame shape around the periphery of the display device.

[0339] By having a bezel, it is possible to house devices for controlling transistors and ICs for accumulating information. It is also possible to protect the display device and improve its strength. On the other hand, by making the bezel thinner, it is possible to make the display device smaller and lighter. It is also possible to make the area on which an image is displayed larger.

[0340] The bezel is preferably disposed within the second adhesive layer and in contact with the second resin layer or the glass layer, although the bezel does not necessarily have to be disposed within the second adhesive layer and may be disposed within the first adhesive layer or between other layers of the laminate.

[0341] The bezel is a colored light-shielding film containing a dye or pigment. The method for forming the bezel is not particularly limited, but it is preferably formed by a coating method, for example. The bezel is preferably formed in a frame shape on a flat surface.

[0342] (4) Glass Layer The laminate of the present invention is attached to a thin film glass, and then attached to a display device.

[0343] (4.1) Overview of Glass Layer (Thin Film Glass) The glass layer according to the present invention is preferably a thin film glass from the viewpoint of excellent durability, flatness, etc. Examples of materials for the thin film glass include lithium aluminosilicate glass, soda-lime glass, borosilicate glass, silica glass, alkali metal aluminosilicate glass, and aluminosilicate glass with a low alkali content.

[0344] The thin film glass is preferably an alkali-free glass that contains substantially no alkali components. Specifically, the content of alkali components is preferably 1000 ppm by mass or less, more preferably 500 ppm by mass or less, and even more preferably 300 ppm by mass or less, based on the total mass of the thin film glass.

[0345] By reducing the alkaline content, it is possible to suppress the replacement of cations on the surface of the thin glass film, which can prevent a phenomenon known as soda blowing. This in turn prevents a decrease in density on the surface of the thin glass film, making it less susceptible to breakage.

[0346] The thickness of the thin film glass is preferably within the range of 10 to 50 μm. By setting the thickness of the thin film glass to 10 μm or more, sufficient impact resistance of the laminate can be obtained. On the other hand, by setting the thickness of the thin film glass to 50 μm or less, sufficient flexibility of the laminate can be obtained. Furthermore, the thinner the thickness of the thin film glass, the thinner the laminate can be, and the thinner the display device can be. From the viewpoint of achieving both impact resistance and flexibility, the thickness of the thin film glass is more preferably within the range of 10 to 40 μm, and even more preferably within the range of 10 to 30 μm.

[0347] (4.2) Method for Producing Glass Layer (Thin Glass Film) The thin glass film (glass layer) can be produced by a commonly known method, such as a float method, a down-draw method, or an overflow down-draw method. Among these, the overflow down-draw method or the float method is preferred because the surface of the thin glass film does not come into contact with the forming member during production and the surface of the obtained thin glass film is less likely to be scratched. Among these, the float method is preferred from the viewpoint of obtaining a thin glass film having a thickness in the range of 10 to 50 μm.

[0348] Generally, the thinner the glass, the weaker the glass and the more susceptible it is to breakage, making it difficult to handle and process thin film glass alone. However, by processing thin film glass while temporarily adhering it to a thicker support substrate (carrier substrate), and then peeling off the support substrate as a post-processing step, handling and processing of thin film glass can be made easier.

[0349] For example, in the technique described in International Publication No. 2017 / 066924, soda lime glass having a thickness of less than 100 μm can be produced by the following steps: Note that Fig. 4 is a schematic diagram showing an example of a method for producing thin film glass.

[0350] 4, in step 1, a thin film glass 22 is fabricated on a carrier substrate 21 having a bonding surface, with a first surface of the thin film glass being in contact with the carrier substrate 21. Then, a contact film 23 having adhesive force is pressure-bonded to a second surface opposite to the first surface.

[0351] That is, a thin-film glass material is poured to a desired thickness onto a carrier substrate 21 having sufficient strength and a thickness that allows easy processing, thereby forming a thin-film glass 22 such that a first surface of the thin-film glass 22 is in contact with the carrier substrate 21. Then, a contact film 23 is pressure-bonded to a second surface opposite the first surface.

[0352] (Step 2) As shown in FIG. 4, in step 2, the thin glass film 22 is peeled off from the carrier substrate 21 by the contact film 23 having high adhesive strength.

[0353] 4, in step 3, a weakening treatment (electromagnetic radiation irradiation 24) is performed to weaken the adhesive strength of the contact film 23. As a result, the contact film 23 is removed from the second surface of the thin film glass 22.

[0354] In this way, the contact film 23 is used to safely hold the thin film glass 22, thereby protecting the thin film glass 22. The exposed surface of the thin film glass 22 can be protected from, for example, mechanical damage, and can be handled safely and easily.

[0355] Examples of materials for the contact film include polyolefins (PO) such as polyethylene terephthalate (PET) and polyethylene (PE).

[0356] The contact film is usually adhered to the thin film glass by an adhesive layer made of an adhesive provided on one side of the substrate, or the contact film may be adhered directly to the thin film glass by the adhesive properties of the contact film itself.

[0357] The adhesive strength between the contact film and the second surface of the thin film glass is appropriately selected so that a peeling device can transmit sufficient force to peel the thin film glass from the carrier substrate.

[0358] The contact film is preferably in the form of a foil or tape, which can be wound into a roll. The thickness of the contact film is preferably 50 μm or more, more preferably 80 μm or more, more preferably 125 μm or more, and particularly preferably 150 μm or more.

[0359] The thin film glass is preferably fabricated on a carrier substrate by a process such as the downdraw process, overflow downdraw process, or float process described above.

[0360] The thickness of the carrier substrate is preferably 100 μm or more, more preferably 300 μm or more, and even more preferably 500 μm or more, and the width of the carrier substrate is preferably 3 inches or more (1 inch is 2.54 cm) or more, more preferably 6 inches or more, even more preferably 8 inches or more, and particularly preferably 12 inches or more.

[0361] In particular, the carrier substrate is preferably equal to or larger than the first generation glass substrate size, for example, second to eighth generation sizes, or may be even larger, for example, 1x1 m to 3x3 m. The carrier substrate may have various shapes, such as rectangular, oval, or circular.

[0362] The thin film glass, together with the contact film, is peeled off from the carrier substrate by the adhesive force of the contact film, and then the contact film is peeled off to obtain a single thin film glass.

[0363] Before peeling the contact film from the thin glass, it is preferable to weaken the adhesive strength of the contact film by subjecting it to an adhesive weakening treatment, specifically to a weakening of the adhesive strength of 0.5 N / 25 mm or less.

[0364] The weakening treatment preferably uses electromagnetic radiation, such as infrared, ultraviolet or visible light, which may be narrow band or may cover a wider band depending on the adhesive material used, or may be laser radiation.

[0365] In particular, it is preferable to select electromagnetic radiation having a wavelength outside the visible spectrum so that the adhesive strength does not deteriorate under exposure to visible light.Some commercially available adhesive materials can be at least partially deactivated by exposure to electromagnetic radiation, and such adhesive materials can be used as contact films.

[0366] If increasing or decreasing the temperature reduces the adhesiveness of the contact film, heat treatment may be used as the weakening treatment.

[0367] The electromagnetic radiation is preferably applied from the outer surface of the contact film, that is, from the side to which the thin film glass is not adhered.

[0368] An example of the contact film is "NDS4150-20" (manufactured by Daoming Optical Co., Ltd.) A corresponding weakening treatment is irradiation with ultraviolet light at a wavelength of 365 nm.

[0369] Specific methods and conditions for producing the thin film glass will be explained in the Examples section. As the thin film glass, commercially available products manufactured by, for example, SCHOTT and Nippon Electric Glass Co., Ltd. can be used.

[0370] 3. Method for Producing the Laminate The method for producing the laminate of the present invention is not particularly limited, and examples thereof include a method in which a cured layer, a resin layer, and an adhesive layer are sequentially disposed.

[0371] 4. Physical Properties of the Laminate From the viewpoint of achieving both impact resistance and flexibility, the thickness of the laminate of the present invention is preferably within a range of 100 to 300 μm, and more preferably within a range of 100 to 200 μm.

[0372] 5. Display Device The display device of the present invention is characterized by including the laminate described above. The laminate preferably has a glass layer. Furthermore, the first resin layer is preferably disposed closer to the viewing side of the display device than the second resin layer. By disposing a layer having ultraviolet absorbing properties closer to the viewing side of the laminate, not only the display device but also other layers of the laminate can be protected from ultraviolet rays.

[0373] The display device of the present invention can be obtained by attaching the laminate to the surface of the display device described below. The laminate preferably has a glass layer. The attachment method is not particularly limited. From the viewpoint of achieving both impact resistance and flexibility, it is preferable to use the pressure-sensitive adhesive for bonding.

[0374] The display device of the present invention may have a polarizing plate between the laminate and the display device described below. However, since the laminate can suppress external light reflection, that is, the laminate has some of the function of a polarizing plate, the display device does not necessarily have to have a polarizing plate.

[0375] In the present invention, the term "display device" refers to a device having a display mechanism, and has a light-emitting element or a light-emitting device as a light source. In addition, in the present invention, a device having a display mechanism is also referred to as a "display member."

[0376] Examples of display devices include liquid crystal display devices, organic electroluminescence (EL) display devices, inorganic electroluminescence (EL) display devices, touch panel display devices, electron emission display devices (field emission displays (FEDs), surface field emission displays (SEDs)), electronic paper (display devices using electronic ink or electrophoresis elements), plasma display devices, projection display devices (grating light valve (GLV) display devices, display devices having digital micromirror devices (DMDs), etc.), piezoelectric ceramic displays, etc. Examples of liquid crystal display devices include transmissive liquid crystal display devices, semi-transmissive liquid crystal display devices, reflective liquid crystal display devices, direct-view liquid crystal display devices, projection liquid crystal display devices, etc.

[0377] These display devices may be display devices that display two-dimensional images or stereoscopic display devices that display three-dimensional images. Among these, organic EL display devices or touch panel display devices are preferred, and organic EL display devices are more preferred.

[0378] The display device of the present invention is provided with the laminate (cover member) and thus can achieve both light resistance and impact resistance.

[0379] An example of application to an organic EL display, which is one example of a display device, is shown in Fig. 5. As shown in Fig. 5, the display device 100 has an organic EL layer 9 on the surface of the glass layer 6 opposite to the second adhesive layer 7. A third adhesive layer 8 may also be provided between the glass layer 6 and the organic EL layer 9. The third adhesive layer may be made of the same material and have the same physical properties as the first adhesive layer and the second adhesive layer, or may be made of a different material and have different physical properties.

[0380] Generally, an organic EL display is composed of an organic EL layer consisting of an electrode, an electron transport layer, a light-emitting layer, a hole transport layer, and a transparent electrode, and a polarizing plate having a retardation plate (λ / 4 plate) for improving image quality. However, since the laminate of the present invention has some of the function of a polarizing plate, it does not necessarily have to have a polarizing plate.

[0381] The display device of the present invention may also be a foldable display. A foldable display preferably has a structure in which a single continuous display is folded in half when carried, thereby reducing the size by half and improving portability. Furthermore, the foldable display is preferably thin and lightweight.

[0382] The laminate of the present invention has good impact resistance and is less likely to leave creases even when repeatedly folded. It also maintains contrast even after repeated folding. Therefore, in a foldable display, it is excellent in visibility after repeated folding, specifically, in suppressing image distortion at the folded portion. Furthermore, because the laminate of the present invention has good light resistance, it can maintain its quality for a long period of time even when applied to a mobile device used outdoors.

[0383] The present invention will be specifically described below with reference to examples, but the present invention is not limited thereto. In the examples, the terms "parts" and "%" are used, but they represent "parts by mass" or "% by mass" unless otherwise specified. In the following examples, operations were carried out at room temperature (25°C) unless otherwise specified.

[0384] 1. Preparation of Laminate In this example, a resin layer was prepared, and then a cured layer was prepared on the resin layer to prepare a two-layer film. Specifically, a two-layer film in which a first cured layer was prepared on a first resin layer, and a two-layer film in which a second cured layer was prepared on a second resin layer were each prepared. Then, the two two-layer films were bonded together via an adhesive layer to prepare a laminate. The layers were bonded together so that they were arranged in the following order: first cured layer, first resin layer, first adhesive layer, second cured layer, and second resin layer.

[0385] (1) Preparation of Resin Layer (1.1) Preparation of Resin Layer 1 (1.1.1) Preparation of Dope 1 (Silicon Dioxide Dispersion) "Aerosil (registered trademark) R812" (manufactured by Nippon Aerosil Co., Ltd., average primary particle diameter 7 nm) 10.000 parts by mass Ethanol 90.000 parts by mass The above components were stirred and mixed in a dissolver for 30 minutes, and then dispersed using a Manton-Gaulin to prepare a silicon dioxide dispersion. The silicon dioxide dispersion was filtered through a fine particle dispersion dilution filter (Advantec Toyo Co., Ltd.: polypropylene wound cartridge filter TCW-PPS-1N).

[0386] Dichloromethane 80.960 parts by mass Ethanol 7.040 parts by mass Silicon dioxide dispersion (10% by mass dispersion) 0.120 parts by mass Dye compound (2-3) 0.720 parts by mass The above components were stirred at 23° C. for 1 hour, and then 12 parts by mass of acetyl cellulose was added thereto, followed by stirring at 23° C. for 4 hours. Then, the mixture was filtered using Azumi Filter Paper No. 24 manufactured by Azumi Filter Paper Co., Ltd. to prepare Dope 1.

[0387] The content of silicon dioxide was 0.1% by mass based on the total mass of the acetyl cellulose. The acetyl cellulose was prepared by a known method using triacetyl cellulose (TAC) having a degree of substitution of 3.0.

[0388] (1.1.2) Formation of Resin Layer 1 Next, the dope 1 was uniformly cast onto a stainless steel band support using a belt casting apparatus to form a cast film. The solvent was evaporated on the stainless steel band support until the residual solvent amount in the cast film reached 100%, and the cast film was peeled off from the stainless steel band support. The cast film was heated at 35°C to evaporate the solvent. The cast film from which the solvent had evaporated was slit into a width of 1.65 m, and the width was held by a tenter and dried at a drying temperature of 160°C. The drying temperature here also served as the heat treatment temperature and the stretching temperature.

[0389] The residual solvent content at the start of drying was 20%. The film was then dried for 15 minutes while being transported by multiple rolls in a drying apparatus at 120°C, after which knurling was performed on both ends of the film to a width of 15 mm and a height of 10 μm. The film was wound around a core to obtain resin layer 1. The residual solvent content of resin layer 1 was 0.2%, the thickness was 40 μm, and the number of windings was 6000 m.

[0390] (1.2) Preparation of Resin Layers 2, 4, 6 to 13, and 15 to 18 Resin layers 2, 4, 6 to 13, and 15 to 18 were prepared in the same manner as in the preparation of Resin Layer 1, except that the type of resin, the type and content of the dye compound, and the thickness were changed as shown in Tables I and II.

[0391] (1.3) Preparation of Resin Layer 3 Resin layer 3 was prepared in the same manner as in the preparation of resin layer 1, except that metal oxide particles were added so that the storage modulus was 6.7 GPa.

[0392] (1.4) Preparation of Resin Layer 5 A resin layer 5 was prepared in the same manner as in the preparation of the resin layer 1, except that the amount of ethanol added in the dope 1 was changed from 7.04 parts by mass to 1.65 parts by mass, and the type of resin was changed.

[0393] (1.5) Fabrication of Resin Layer 14 (1.5.1) Preparation of Thermoplastic (Meth)acrylic Resin As the thermoplastic (meth)acrylic resin, a MMA (methyl methacrylate) / PMI (phenylmaleimide) / MA (methyl acrylate) copolymer (85 / 10 / 5 mass ratio, Mw: 2,000,000, Tg: 122°C) was prepared.

[0394] (1.5.2) Preparation of Rubber Particles (Graft Copolymer) R1 Rubber particles (graft copolymer) prepared by the following method were used.

[0395] The following components were charged into an 8 L polymerization apparatus equipped with a stirrer to prepare solution I: Deionized water 180.000 parts by mass Polyoxyethylene lauryl ether phosphate 0.002 parts by mass Boric acid 0.473 parts by mass Sodium carbonate 0.047 parts by mass Sodium hydroxide 0.008 parts by mass

[0396] After the inside of the polymerization apparatus was thoroughly purged with nitrogen gas, the inside temperature was raised to 80° C., and the following components were added: potassium persulfate (added as a 2% by mass aqueous solution) 0.021 parts by mass

[0397] Next, a monomer mixture (c') consisting of the following components was prepared: 84.6% by mass of methyl methacrylate (methyl methacrylate), 5.9% by mass of n-butyl acrylate (n-butyl acrylate), 7.9% by mass of styrene, 0.5% by mass of allyl methacrylate (allyl methacrylate), and 1.1% by mass of n-octyl mercaptan.

[0398] A mixed solution containing the following components was then prepared: Monomer mixture (c') 21.000 parts by mass Polyoxyethylene lauryl ether phosphate 0.070 parts by mass This mixed solution was then continuously added to the above solution I over 63 minutes. The polymerization reaction was continued for a further 60 minutes to obtain a hard polymer (crosslinked polymer (c)) contained in the innermost portion.

[0399] Thereafter, the following components were added to prepare Solution II: 0.021 parts by mass of sodium hydroxide (added as a 2% by mass aqueous solution) 0.062 parts by mass of potassium persulfate (added as a 2% by mass aqueous solution)

[0400] Next, a monomer mixture (a') consisting of the following components was prepared: n-butyl acrylate (n-butyl acrylate) 80.0% by mass, styrene 18.5% by mass, and allyl methacrylate (allyl methacrylate) 1.5% by mass.

[0401] A mixed solution consisting of the following components was prepared: Monomer mixture (a') 39.000 parts by mass Polyoxyethylene lauryl ether phosphate 0.250 parts by mass This mixed solution was then continuously added to Solution II over 117 minutes.

[0402] The following components were then added: Potassium persulfate (added as a 2% by mass aqueous solution) 0.012 parts by mass The polymerization reaction was continued for 120 minutes to obtain a soft layer (a layer made of acrylic rubber-like polymer (a)). The glass transition temperature (Tg) of the soft layer, calculated by averaging the glass transition temperatures of the homopolymers of each monomer constituting the acrylic rubber-like polymer (a) according to the composition ratio, was -30°C.

[0403] Thereafter, the following components were added to prepare Solution III: Potassium persulfate (added as a 2% by weight aqueous solution) 0.040 parts by weight

[0404] Then, a monomer mixture (b') consisting of the following components was prepared: 97.5% by mass of methyl methacrylate (methyl methacrylate), 2.5% by mass of n-butyl acrylate (n-butyl acrylate).

[0405] The following monomer mixture (b') was continuously added to Solution III over 78 minutes. The polymerization reaction was continued for another 30 minutes to obtain a methacrylic polymer (b). Monomer mixture (b') 26.100 parts by mass

[0406] The obtained methacrylic polymer (b) was poured into a warm 3% by mass aqueous solution of sodium sulfate, and salted out and coagulated. Subsequently, the mixture was repeatedly dehydrated and washed, and then dried to obtain acrylic graft copolymer particles (rubber particles) R1 having a three-layer structure. The average particle diameter of the obtained rubber particles R1 was measured using a zeta potential / particle size measurement system "ELSZ-2000ZS" (manufactured by Otsuka Electronics Co., Ltd.) and found to be 200 nm. The glass transition temperature (Tg) of the rubber particles was -30°C.

[0407] (1.5.3) Preparation of surfactant solution The following components were mixed and dissolved to prepare a surfactant solution: 98,000 parts by mass of methyl ethyl ketone (MEK) 2,000 parts by mass of Phosphanol ML-220 (polyoxyethylene lauryl ether phosphate, manufactured by Toho Chemical Industry Co., Ltd.)

[0408] (1.5.4) Preparation of Dope The following components were charged as a solvent into a dissolution tank in which the nitrogen concentration was controlled to 98.5% by volume and the oxygen concentration was controlled to 1.5% by volume: 85.300 parts by mass of methyl ethyl ketone. Next, the following components were charged into the dissolution tank containing the solvent, and stirred for 30 minutes: 15.000 parts by mass of surfactant solution 0.660 parts by mass of the dye compound (2-3)

[0409] Thereafter, the following components were added while stirring, and stirring was continued at 23°C for 1 hour to disperse the rubber particles (graft copolymer): 2.200 parts by mass of rubber particles (graft copolymer particles) Then, the following components were added to the dissolution tank while stirring, and then stirred at 23°C for 4 hours to completely dissolve the solids, completing the dope: 8.800 parts by mass of thermoplastic (meth)acrylic resin

[0410] (1.5.5) Formation of Resin Layer 14 A PET film "TN100" (manufactured by Toyobo Co., Ltd., 50 μm thick, with a release layer containing a non-silicone release agent) was prepared as a substrate. The dope was applied onto the release layer of this PET film using a die by a backcoat method, and then dried at 80°C in an atmosphere with a solvent concentration of 0.18% by volume. The substrate was then peeled off to obtain a 40 μm thick resin layer 14.

[0411] (1.6) Preparation of Resin Layer 19 A resin layer 19 was prepared in the same manner as in the preparation of the resin layer 14, except that no dye compound was added and the thickness was changed to 50 μm.

[0412] The resins and dye compounds used were as follows:

[0413] (Resins) TAC: triacetyl cellulose DAC: diacetyl cellulose COP: cycloolefin resin "ARTON G7810" (manufactured by JSR Corporation) CPI: polymer (polyimide) having structural units derived from 4,4'-(hexafluoroisopropylidene)diphthalic anhydride and structural units derived from 2,2'-bis(trifluoromethyl)benzidine, Mw: 150,000, Tg: 350°C Acrylic: MMA (methyl methacrylate) / PMI (phenylmaleimide) / MA (methyl acrylate) copolymer (85 / 10 / 5 mass ratio, Mw: 2,000,000, Tg: 122°C) PET: polyethylene terephthalate "E5000" (manufactured by Toyobo Co., Ltd.)

[0414] (Dye Compounds) Compound (1-2): Dye compound (1-2) exemplified above Compound (1-13): Dye compound (1-13) exemplified above Compound (2-2): Dye compound (2-2) exemplified above Compound (2-3): Dye compound (2-3) exemplified above Compound (2-8): Dye compound (2-8) exemplified above Compound (2-11): Dye compound (2-11) exemplified above Compound a: "Kayaset Black A-N" (manufactured by Nippon Kayaku Co., Ltd.)

[0415] The chemical structure of the compound is shown below.

[0416]

[0417] (2) Preparation of Cured Layer (2.1) Preparation of Cured Layer 1 (2.1.1) Preparation of Cured Layer Forming Composition Resin: Pentaerythritol tri / tetraacrylate "NK Ester A-TMM-3L" (manufactured by Shin-Nakamura Chemical Co., Ltd.) 100.000 parts by mass Photopolymerization initiator: "Irgacure 184" (manufactured by BASF Japan Ltd.) 9.000 parts by mass Solvent: Propylene glycol monomethyl ether 20.000 parts by mass Methyl acetate 30.000 parts by mass Methyl ethyl ketone 70.000 parts by mass Additives: Surfactant: "KF-351A" (polyether-modified silicone oil, manufactured by Shin-Etsu Chemical Co., Ltd.) 2.000 parts by mass Fine particles: Polymer silane coupling agent-coated silica 100.000 parts by mass

[0418] (Preparation of Fine Particles) The polymer silane coupling agent-coated silica was prepared as follows. The following components were added to a container, and N ２ After the atmosphere was replaced with gas, the mixture was heated at 80° C. for 3 hours to prepare a polymer silane coupling agent. The molecular weight of the obtained polymer silane coupling agent was 16,000. The molecular weight was measured using a gel permeation chromatography device.

[0419] Methyl methacrylate "Light Ester M" (Kyoeisha Chemical Co., Ltd.) 30 mL 3-mercaptopropyltrimethoxysilane "KBM-803" (Shin-Etsu Chemical Co., Ltd.) 1 mL Solvent: tetrahydrofuran 100 mL Polymerization initiator: azoisobutyronitrile "AIBN" (Kanto Chemical Co., Ltd.) 50 mg

[0420] Next, the following components were subjected to ion exchange using an ion exchange resin. Then, water was replaced with ethanol as a solvent by an ultrafiltration membrane method, and 100 g of an ethanol dispersion of silica fine particles (SiO ２ A silica sol "Cataloid Si-45P" (manufactured by JGC Catalysts and Chemicals Industries, Ltd., SiO ２ Concentration 30% by mass, average particle diameter 45nm, dispersion medium: water)

[0421] 100 g of this silica fine particle ethanol dispersion and 1.5 g of the polymer silane coupling agent were dispersed in 20 g (25 mL) of acetone. 20 mg of 29.8% by mass ammonia water was added to this dispersion. The mixture was stirred at room temperature for 30 hours to allow the polymer silane coupling agent to be adsorbed onto the silica fine particles.

[0422] Thereafter, silica particles with an average particle size of 5 μm were added, and the mixture was stirred for 2 hours, so that the unadsorbed polymer silane coupling agent in the solution was adsorbed onto the silica particles.Then, the unadsorbed silica particles with an average particle size of 5 μm that had adsorbed the polymer silane coupling agent were removed by centrifugation.1000 g of ethanol was added to the silica microparticle dispersion that had adsorbed the polymer silane coupling agent, so that the silica microparticles were precipitated.The silica microparticles were separated, dried under reduced pressure, and dried at 25 ° C for 8 hours, so as to obtain silica coated with a polymer silane coupling agent.The average particle size of the obtained polymer silane coupling agent-coated silica was 57 nm.The average particle size was measured using a laser particle size measuring device.

[0423] (2.1.2) Formation of Cured Layer 1 The composition for forming a cured layer prepared above was applied onto the resin layer prepared above using a bar coater so that the dry film thickness was 2.5 μm. This coating layer was dried in a drying oven at 50° C. for 40 seconds to volatilize the solvent. Then, while purging with nitrogen to make the atmosphere in an oxygen concentration of 1.0% by volume or less, an ultraviolet lamp was used to set the illuminance of the irradiated area at 100 mW / cm. ２ , the irradiation dose was 0.2 J / cm ２ The coating layer was cured to prepare a cured layer 1.

[0424] (3) Preparation of Adhesive Layer (3.1) Preparation of Adhesive Layer 1 (3.1.1) Preparation of UV-Curable Acrylic Adhesive Composition (a-1) A monomer mixture consisting of the following components was prepared: 2-Ethylhexyl acrylate (2EHA) 78.000 parts by mass N-Vinyl-2-pyrrolidone (NVP) 18.000 parts by mass 2-Hydroxyethyl acrylate (HEA) 4.000 parts by mass

[0425] Then, the following components were added as photopolymerization initiators: 1-hydroxycyclohexyl phenyl ketone 0.035 parts by mass 2,2-dimethoxy-1,2-diphenylethan-1-one 0.035 parts by mass The following commercially available photopolymerization initiators were used: 1-hydroxycyclohexyl phenyl ketone: "Omnirad (registered trademark) 184" (having an absorption band in the wavelength range of 200 to 370 nm, manufactured by IGM Resins B.V.) 2,2-dimethoxy-1,2-diphenylethan-1-one: "Omnirad (registered trademark) 651" (having an absorption band in the wavelength range of 200 to 380 nm, manufactured by IGM Resins B.V.)

[0426] Thereafter, the mixture was irradiated with ultraviolet light until the viscosity (measurement conditions: BH viscometer No. 5 rotor, 10 rpm, measurement temperature 30°C) reached approximately 20 Pa s. As a result, a prepolymer composition (polymerization rate: 8%) in which a portion of the monomer components was polymerized was obtained.

[0427] Next, the following components were added to the prepolymer composition and mixed to obtain an acrylic pressure-sensitive adhesive composition: 0.150 parts by mass of hexanediol diacrylate (HDDA) 0.300 parts by mass of silane coupling agent "KBM-403" (manufactured by Shin-Etsu Chemical Co., Ltd.)

[0428] The following components were added to the obtained acrylic pressure-sensitive adhesive composition and stirred to obtain an ultraviolet-curable acrylic pressure-sensitive adhesive composition (a-1): 2,4-bis-[{4-(4-ethylhexyloxy)-4-hydroxy}-phenyl]-6-(4-methoxyphenyl)-1,3,5-triazine (dissolved in n-butyl acrylate to give a solids concentration of 15% by mass and added) 1.400 parts by mass Bis(2,4,6-trimethylbenzoyl)-phenylphosphine oxide 0.200 parts by mass The following commercially available products were used. 2,4-bis-[{4-(4-ethylhexyloxy)-4-hydroxy}-phenyl]-6-(4-methoxyphenyl)-1,3,5-triazine: "Tinosorb (registered trademark) S" (manufactured by BASF Japan Ltd.) Bis(2,4,6-trimethylbenzoyl)-phenylphosphine oxide: "Omnirad (registered trademark) 819" (having an absorption band in the wavelength range of 200 to 450 nm, manufactured by IGM Resins B.V.)

[0429] (3.1.2) Formation of Adhesive Layer 1 The obtained ultraviolet-curable acrylic adhesive composition (a-1) was applied onto the surface of a release film so that the thickness after curing would be 25 μm, and further, a release film was attached to the surface. Thereafter, illuminance: 6.5 mW / cm ２ , cumulative light amount: 1500 mJ / cm ２ The composition was cured by irradiating it with ultraviolet light under the conditions of (a) and (b), and the release film was peeled off to form an adhesive layer 1.

[0430] (4) Preparation of Laminate Two types of two-layer films obtained by preparing a cured layer on a resin layer were combined as shown in the table and laminated together via the adhesive layer to prepare a laminate. The layers were laminated together in the following order: first cured layer, first resin layer, first adhesive layer, second cured layer, second resin layer.

[0431] (5) Preparation of Glass Layer (Thin Glass) (5.1) Preparation of Glass Layer 1 A glass layer (soda lime glass) having a size of 12 inches was prepared according to the following steps.

[0432] (Step 1) A thin film glass was fabricated on a carrier substrate having a bonding surface, with a first surface of the thin film glass in contact with the carrier substrate. Then, a contact film (also referred to as a "contact film") with high adhesive strength was attached to a second surface of the thin film glass opposite the first surface. (Step 2) The thin film glass was then peeled off from the carrier substrate by the highly adhesive contact film. (Step 3) The contact film was removed from the second surface of the thin film glass peeled off from the carrier substrate by a weakening treatment (electromagnetic radiation irradiation) that weakened the adhesive strength of the contact film.

[0433] In step 1, a thin glass film was prepared to a predetermined thickness so as to be in contact with a 500 μm-thick carrier substrate, and then the contact film described below was attached. Next, in step 2, the thin glass film together with the contact film was peeled off from the carrier substrate over a period of 30 seconds. The commercially available contact film "NDS4150-20" was used. "NDS4150-20" is a 150 μm-thick film containing polyolefin (PO), and further has a 10 μm-thick adhesive layer.

[0434] Next, in step 3, the exposed contact film was subjected to a weakening treatment to reduce the adhesive strength. In the weakening treatment, the contact film was irradiated with ultraviolet light having a wavelength of 365 nm for 10 seconds. The irradiance of the ultraviolet light was 500 mW / cm. ２ , the cumulative light intensity is 500 mJ / cm ２ The adhesive strength before the weakening treatment was 11 N / 25 mm, but after the weakening treatment, the adhesive strength was reduced to 0.4 N / 25 mm. As a result, the contact film could be easily peeled off from the thin glass, and a glass layer with a thickness of 30 μm was obtained.

[0435] (5.2) Preparation of Glass Layer 2 Glass layer 2 was prepared in the same manner as in the preparation of glass layer 1, except that the thickness was changed to 10 μm.

[0436] (6) Preparation of Laminate Having Glass Layer The laminate and the glass layer were bonded together via the adhesive layer to prepare a laminate having a glass layer. The layers were bonded together in the following order: first cured layer, first resin layer, first adhesive layer, second cured layer, second resin layer, second adhesive layer, and glass layer.

[0437] The structures of the obtained laminates are shown in Tables I to III below. A "-" in the tables indicates that the corresponding layer is not present or that the corresponding component is not contained. The "wavelength" in the tables indicates the maximum absorption wavelength in the ultraviolet-visible light absorption spectrum of the dye compound in the wavelength range of 300 to 460 nm. The "content" in the tables indicates the content of the dye compound relative to the total mass of the resin. Note that for the resin layer 14, the total mass of the thermoplastic (meth)acrylic resin and rubber particles was defined as the total mass of the resin.

[0438]

[0439]

[0440]

[0441] 2. Method for Measuring Physical Properties of Resin Layer (Average Light Transmittance of First Resin Layer) The resin layer was conditioned for 24 hours in an air-conditioned room at a temperature of 23°C and a relative humidity of 55RH. Then, in accordance with JIS K-7375:2008, the light transmittance was measured using a UV-visible spectrophotometer "UV-2450" (manufactured by Shimadzu Corporation), and the arithmetic average value was calculated in the wavelength range of 450 to 800 nm.

[0442] (Storage modulus of first resin layer and second resin layer) The storage modulus of each resin layer at 25°C was measured using a rheometer "RSA-3" (manufactured by TA Instruments Japan Inc.) under the following test conditions. Test conditions (dynamic viscoelasticity test) Testing machine: Dynamic viscoelasticity measuring device "RSA-3" (manufactured by TA Instruments Japan Inc.) Deformation method: Tension Preload: 55 g Temperature range: -70 to 200°C Frequency: 1.0 Hz Displacement: ±0.1% Sample: Width 5 mm Distance between chucks: 20 mm

[0443] Table IV below shows the measurement results of the physical properties of the first resin layer and the second resin layer in each laminate. In the table, "Average light transmittance from 450 to 800 nm" represents the arithmetic mean value of light transmittance in the wavelength region of 450 to 800 nm. In the table, "Elastic modulus 2 / Elastic modulus 1" represents the value expressed as "Storage modulus 2 of the second resin layer / Storage modulus 1 of the first resin layer." In other words, it represents the ratio of the storage modulus at 25°C of the second resin layer to that of the first resin layer.

[0444]

[0445] 3. Evaluation The resulting laminates were each evaluated as follows.

[0446] (1) Light resistance The glass layer of each laminate obtained above was bonded to the viewing side of a display device obtained by laminating an organic EL layer via a third adhesive layer. For laminates without a glass layer, the second resin layer was bonded to the viewing side of a display device obtained by laminating an organic EL layer via a third adhesive layer. This display device was illuminated from the viewing side by a xenon lamp (60 W / m ２ ) light was continuously irradiated for 100 hours. After that, a black image was displayed. The front reflectance was measured using a spectrophotometer "CM-2600d" (manufactured by Konica Minolta, Inc.), and the front reflectance was evaluated according to the following criteria. Note that if the evaluation was A or higher (AAA to A), the display was suitable for practical use.

[0447] AAA: 1.5 or less. AA: More than 1.5 and 1.6 or less. A: More than 1.6 and 1.7 or less. B: More than 1.7 and 1.8 or less. C: More than 1.8.

[0448] (2) Pen Drop Test (Impact Resistance) An organic EL layer was laminated on the glass layer of each laminate obtained above, with the first cured layer positioned at the top, to obtain a display device. For laminates without a glass layer, an organic EL layer was laminated on the second resin layer, with the first cured layer positioned at the top, to obtain a display device. A ballpoint pen with a pen tip radius (R) of 0.35 mm and a weight (m) of 12 g was dropped onto the surface of the first cured layer of each display device, while varying the drop height. A black image was displayed on each display device after the pen drop test. Then, the front reflectance was measured using a spectrophotometer "CM-2600d" (manufactured by Konica Minolta, Inc.) and evaluated according to the following criteria. Note that a rating of A or higher (AAA to A) indicates practical use.

[0449] AAA: 1.5 or less. AA: More than 1.5 and 1.6 or less. A: More than 1.6 and 1.7 or less. B: More than 1.7 and 1.8 or less. C: More than 1.8.

[0450] Table V below shows the evaluation results for each laminate.

[0451]

[0452] From the examples and comparative examples, it can be seen that the laminate of the present invention can achieve both light resistance and impact resistance. From the comparison of Examples 1 to 5, it can be seen that by including cellulose ester in the first resin layer, it can achieve both light resistance and impact resistance.

[0453] It can be seen from Examples 8 and 14 that the light transmittance of the resin layer can be adjusted to a desired value when the dye compound has a structure represented by the above general formula (1). It can be seen from Examples 1 and 11 to 13 that the light transmittance of the resin layer can be adjusted to a desired value when the dye compound has a structure represented by the above general formula (2).

[0454] From Examples 8 and 9, it can be seen that both light resistance and impact resistance can be achieved when the thickness of the glass layer is in the range of 10 to 30 μm.

[0455] By using the present invention, it is possible to provide a display device that is both light-resistant and impact-resistant.

[0456] REFERENCE SIGNS LIST 1 First cured layer 2 First resin layer 3 First adhesive layer 4 Second cured layer 5 Second resin layer 6 Glass layer 7 Second adhesive layer 8 Third adhesive layer 9 Organic EL layer 10 Laminate 11 Laminate 12 Laminate 21 Carrier substrate 22 Thin film glass 23 Contact film 24 Electromagnetic radiation 100 Display device

Claims

1. A laminate having a resin layer, a cured layer and an adhesive layer, laminated in the following order: a first cured layer, a first resin layer, a first adhesive layer, a second cured layer and a second resin layer; the first resin layer contains a dye compound whose maximum absorption wavelength is in the range of 360 to 379 nm in an ultraviolet-visible light absorption spectrum of a wavelength range of 300 to 460 nm; the first resin layer has an average light transmittance of 87% or more in a wavelength range of 450 to 800 nm; the first resin layer has a storage modulus at 25°C in the range of 4.0 to 8.0 GPa; and the ratio of the storage modulus at 25°C of the second resin layer to that of the first resin layer is in the range of 0.7 to 1.

5.

2. The laminate according to claim 1, wherein the first resin layer contains a cellulose ester.

3. The laminate according to claim 1, wherein the dye compound has a structure represented by the following general formula (1): (In the formula, R １１ represents a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group, a hydroxy group, an amino group, an alkyl-substituted amino group, a carboxy group, an alkyloxycarbonyl group, a hydroxyalkyl group, an alkylcarbonyloxyalkyl group, a carboxyalkyl group, an alkyloxycarbonylalkyl group, an aryl group, an acyl group, or a sulfo group. １２ represents a hydrogen atom or a hydroxyl group.

4. The laminate according to claim 1, wherein the dye compound has a structure represented by the following general formula (2): (In the formula, R ２１ represents a hydrogen atom or a hydroxy group. ２２ , R ２３ , and R ２４ represents an alkyl group, an alkoxy group, an alkyl-substituted amino group, a carboxy group, an alkyloxycarbonyl group, a hydroxyalkyl group, an alkylcarbonyloxyalkyl group, a carboxyalkyl group, an alkyloxycarbonylalkyl group, an aryl group, an acyl group, or a sulfo group.

5. The laminate according to claim 1, wherein the thickness of the first resin layer is within the range of 15 to 50 μm.

6. The laminate according to claim 1, wherein the storage modulus of the second resin layer at 25°C is within the range of 4.0 to 8.0 GPa.

7. A laminate according to any one of claims 1 to 6, further comprising a glass layer, and wherein the first hardened layer, the first resin layer, the first adhesive layer, the second hardened layer, the second resin layer, and the glass layer are laminated in this order.

8. The laminate according to claim 7, further comprising a second adhesive layer, and is laminated in the following order: the first cured layer, the first resin layer, the first adhesive layer, the second cured layer, the second resin layer, the second adhesive layer, and the glass layer.

9. The laminate according to claim 7, wherein the thickness of the glass layer is within the range of 10 to 30 μm.

10. The laminate described in claim 8, further comprising a third adhesive layer, and is laminated in the following order: the first cured layer, the first resin layer, the first adhesive layer, the second cured layer, the second resin layer, the second adhesive layer, the glass layer, and the third adhesive layer.

11. A display device comprising the laminate according to claim 10.

12. The display device according to claim 11, characterized in that the first resin layer of the laminate is disposed closer to the viewing side of the display device than the second resin layer.

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