TW202349763A - Optical laminate for OLED display device - Google Patents

Abstract

Provided is an optical laminate for use in an OLED display device that does not use a polarizing plate and is not susceptible to interference variations. The present invention provides an optical laminate for use in an OLED display device in which only an optical element having a degree of polarization of 95% or less is laminated on the viewing side of an OLED element. The optical element has at least an antireflection layer on the viewing side thereof.

Description

Optical laminate for OLED display device

The present invention relates to an optical laminated body for an OLED display device. More specifically, the present invention relates to an optical laminate used in an OLED display device that does not use a polarizing plate.

Compared with liquid crystal display devices, OLED (Organic light emitting diode) display devices have advantages in display performance such as higher visibility, lower viewing angle dependence, and faster response speed. In addition, since the OLED display device does not use a backlight device, it is advantageous to be thinner, and can also be used as a foldable device that can be flexibly bent or bent.

OLED display devices generally have OLED elements in which an anode, an OLED layer including a light-emitting layer, and a cathode are laminated in sequence. Since the electrodes (anode or cathode) of OLED elements use high-refractive-index transparent conductive materials such as ITO (Indium Tin Oxides) or high-reflectivity metal materials, external light is reflected by the electrodes, resulting in reduced contrast. Or internal reflection problems may cause the display performance of the OLED display device to deteriorate.

In order to suppress adverse effects caused by external light reflection, it is proposed to arrange a polarizing plate and a circular polarizing plate such as a λ/4 plate on the viewing side of an OLED display device (for example, Patent Document 1). This type of circular polarizing plate also has the function of blocking ultraviolet rays contained in external light and preventing the degradation of OLED components caused by ultraviolet rays. Furthermore, it also has the function of absorbing impact from the outside through the mechanical properties of the circular polarizing plate itself and preventing damage to the OLED display device.

However, if a circularly polarizing plate is used, the light utilization efficiency (ie, daylighting efficiency) will be poor due to the absorption caused by the polarizing plate, and the brightness will be reduced. If the luminous intensity of the OLED element is increased in order to obtain the required brightness, the power consumption will increase and the life of the OLED element will be shortened. In addition, if the polarizing plate includes an adhesive layer for attachment, the thickness will reach about 0.15 mm, which is not conducive to the thinning of the OLED display device. Furthermore, since the price of circularly polarizing plates is relatively high, there is also a problem of high manufacturing costs.

As an alternative to circular polarizers, the following method has been proposed: Arrange a color filter on the viewing side of the OLED element, and position it so that it faces a color filter of the same color as the OLED layer's luminous color. This prevents reflection of external light and improves the luminous brightness of the OLED element (for example, Patent Document 2).

As one type of OLED display device, an OLED display device having a microcavity (also called multiple reflection interference, optical resonator or microresonator) structure is known. According to the OLED display device having a microcavity structure, the spectrum of the light extracted to the outside becomes steep and high-intensity, so it is considered that the brightness and color purity can be improved (for example, Patent Document 3).

In an OLED display device, in order to provide functions such as surface protection and flexibility to the viewing side of the OLED element, layers of various optical elements such as an adhesive layer, a base material such as plastic or thin glass, and a hard coating layer are laminated. [Prior technical literature] [Patent Document]

Patent Document 1: Japanese Patent Application Publication No. 2003-332068 Patent Document 2: Japanese Patent Application Publication No. 2018-112715 Patent Document 3: Japanese Patent Application Publication No. 2015-207377

[Problem to be solved by the invention]

As an alternative to the circular polarizer, that is, a color filter is arranged on the viewing side of the OLED element, and the position is aligned in such a manner that it faces a color filter of the same color as the luminous color of the OLED layer, thereby preventing external interference. The method of reflecting light and improving the luminous brightness of OLED elements may cause interference spots of reflected light due to the regular two-dimensional structure of the color filter, which may damage the visibility of the OLED display device.

Therefore, an object of the present invention is to provide an optical laminate used in an OLED display device that is less likely to generate interference spots in an OLED display device that does not use a polarizing plate. [Technical means to solve problems]

The present inventors conducted intensive research to achieve the above object, and found that an interference pattern can be provided by laminating an optical laminate including an antireflection layer on the viewing side of the OLED element in an OLED display device that does not use a polarizing plate. An OLED display device suppressed was obtained, thereby completing the present invention.

That is, the present invention provides an optical laminate for an OLED display device, which is an optical laminate used in an OLED display device in which only optical elements with a polarization degree of 95% or less are laminated on the viewing side of the OLED element, and the optical element has at least a resistance to reflective layer.

Preferably, in the reflectance spectrum of the above-mentioned OLED display device in a state where the above-mentioned optical laminate for OLED display devices is not laminated, the maximum value at a wavelength of 380 to 455 nm is set to Rp1, and the maximum value at the wavelength of Rp1 is preferably When the reflectance of the anti-reflection layer is Rf1, [Rf1/Rp1] is 0.3 or less.

Preferably, in the reflectance spectrum of the above-mentioned OLED display device in a state where the above-mentioned optical laminate for OLED display devices is not laminated, the maximum value at a wavelength of 460 to 530 nm is set to Rp2, and the maximum value at the wavelength of Rp2 is preferably When the reflectivity of the anti-reflection layer is Rf2, [Rf2/Rp2] is 0.12 or less.

The total of the above-mentioned [Rf1/Rp1] and the above-mentioned [Rf2/Rp2] is preferably 0.42 or less.

The water contact angle of the anti-reflective layer is preferably above 100°.

The water contact angle of the above-mentioned anti-reflective layer after the eraser test is preferably above 90°.

The anti-reflection layer preferably contains inorganic substances.

Preferably, a hard coat layer, a base material layer, and an adhesive layer are provided on the side opposite to the viewing side of the anti-reflection layer.

The haze value of the above-mentioned adhesive layer is preferably 20 to 90%.

The thickness of the above-mentioned hard coating layer is preferably 2 to 10 μm. [Effects of the invention]

The OLED display device of the present invention uses an optical laminate volume and is laminated on the viewing side of the OLED element. The OLED display device is less likely to generate interference spots and has excellent visibility.

The present invention provides an optical laminated body used in an OLED display device (optical laminated body for OLED display devices) in which only optical elements with a polarization degree of 95% or less are laminated on the viewing side of the OLED element. The optical laminated body for the OLED display device of the present invention is sometimes called the "optical laminated body of the present invention", and the OLED display device using the optical laminated body of the present invention is sometimes called the "OLED display device of the present invention". The optical element of the optical laminated body of the invention is called the "optical element of the invention."

The OLED display device of the present invention has as essential components an OLED display panel and an optical laminate of the present invention laminated on the viewing side of the OLED element. The OLED display panel includes an anode and a luminescent layer laminated in this order. OLED display panel of OLED elements with OLED layer and cathode. The OLED display panel constituting the OLED display device of the present invention is sometimes referred to as the "OLED display panel of the present invention."

The OLED display device of the present invention only has optical elements with a polarization degree of 95% or less laminated on the viewing side of the OLED element of the OLED display panel. "Only optical elements with a polarization degree of less than 95% are laminated on the viewing side of the OLED element" means that the optical elements on the viewing side of the OLED element do not contain optical elements with a polarization degree of more than 95%. "Optical elements with a polarization degree exceeding 95%" are not particularly limited and include polarizing plates such as linear polarizing plates, 1/4 phase difference plates, 1/2 phase difference plates, circular polarizing plates, reflective polarizing plates, etc. That is, the OLED display device of the present invention does not include a polarizing plate on the viewing side of the OLED element. The degree of polarization is determined by the following formula based on the parallel transmittance Tp and the cross transmittance Tc measured using a UV-visible spectrophotometer and corrected for visual sensitivity. Polarization degree (%)={(Tp－Tc)/(Tp＋Tc)}1/2×100

The OLED display device of the present invention does not contain a polarizing plate on the viewing side of the OLED element, so that the light emitted from the OLED element is suppressed from being absorbed by the polarizing plate, and the lighting rate of the light is increased, which can save power consumption and bring about better performance of the OLED element. Long life. In addition, by not using a polarizing plate, the thickness can be reduced, and the manufacturing cost can also be reduced.

The optical element of the present invention at least has an anti-reflection layer. By having an anti-reflection layer, the optical element of the present invention is less likely to produce the interference spots of the OLED display device of the present invention and has excellent visibility, so it is preferable.

In another embodiment of the OLED display device of the present invention, the optical element of this embodiment preferably has at least an adhesive layer, and at least one of the adhesive layers has light scattering properties. The adhesive layer constituting the optical laminate of this embodiment is preferably configured to have light scattering properties in order to suppress color shift or interference spots caused by the OLED display device of this embodiment and to provide excellent visibility.

In another embodiment of the OLED display device of the present invention, it is preferable that a color filter is disposed on the viewing side of the OLED element, and only the optical element of this embodiment is laminated on the viewing side of the color filter. The optical element of this embodiment preferably has at least an adhesive layer, and at least one layer of the adhesive layer has light scattering properties. The distance (d) between the adhesive layer with light scattering properties and the color filter is below 700 μm. By setting the distance between the adhesive layer having light scattering properties and the color filter to 700 μm or less, the light scattering layer can be laminated in order to suppress color shift or interference spots caused by the OLED display device of this embodiment. , it is also less likely to produce image blur, and has excellent visibility, so it is more suitable in this aspect.

In another embodiment of the OLED display device of the present invention, the optical element of this embodiment preferably has at least an anti-glare layer. By having an anti-glare layer, the optical element of this embodiment suppresses color shift or interference spots caused by the OLED display device of this embodiment, and has excellent visibility, which is suitable in this aspect.

In another embodiment of the OLED display device of the present invention, the optical element of this embodiment preferably has at least a glass layer and a resin layer, and the glass layer and the resin layer are connected by an adhesive layer. In the optical laminated body of this embodiment, it is preferable that the glass layer and the resin layer are connected by an adhesive layer, so that the impact resistance of the OLED display device of this embodiment is improved.

In another embodiment of the OLED display device of the present invention, the optical element of this embodiment preferably has at least a transparent polyimide layer and a hard coating layer. By having the optical element of this embodiment with a transparent polyimide layer and a hard coat layer, the impact resistance of the OLED display device of this embodiment is improved, so it is preferable. Each structure is explained below.

(OLED display panel) The OLED display panel used in the OLED display device of the present invention includes, as a necessary component, an OLED element in which an anode, an OLED layer including a light-emitting layer, and a cathode are laminated in this order. The optical laminate of the present invention is laminated on the viewing side of the OLED element of the OLED display panel.

Hereinafter, one embodiment of the OLED display panel constituting the OLED display device of the present invention will be described with reference to the drawings, but the present invention is not limited to this embodiment. FIG. 1 is a schematic cross-sectional view of an embodiment of an OLED display panel of the present invention.

As shown in FIG. 1 , the OLED display panel 100 has: a red OLED element 12R, which is laminated with a transparent electrode 11a, a red OLED layer 10R that emits red light, and a back electrode 11b in this order; and a green OLED element 12G, which is laminated with a transparent electrode 11a in this order. The electrode 11a, the green OLED layer 10G that emits green light, and the back electrode 11b; and the blue OLED element 12B, which is sequentially laminated with the transparent electrode 11a, the blue OLED layer 10B that emits blue light, and the back electrode 11b. OLED elements 12R, 12G, and 12B of various colors are sequentially arranged on the substrate 13. A TFT (Thin Film Transistor, thin film transistor) layer 14 is formed on the surface of the substrate 13 where each OLED element is arranged, and is connected to the back electrode 11b of the OLED elements 12R, 12G, and 12B of a plurality of colors.

In the OLED display panel 100 of FIG. 1 , a color filter 15 is arranged on the viewing side (the upper side in FIG. 1 ) of each of the plurality of colors of OLED elements 12R, 12G, and 12B. The color filter 15 includes a red colored layer 15R, a green colored layer 15G, and a blue colored layer 15B, and a black matrix layer 16 is provided between the colored layers.

In FIG. 1 , the color filter 15 has a red colored layer 15R, a green colored layer 15G, and a blue colored layer 15B respectively facing the red OLED element 12R, the green OLED element 12G, and the blue OLED element 12B. configuration.

The transparent electrode 11a is either a cathode or an anode, and is usually provided as a cathode. As a material for forming the transparent electrode 11a, transparent conductive materials such as ITO (indium tin oxide), indium oxide, IZO (indium zinc oxide), SnO ₂ , and ZnO can be used.

The back electrode 11b functions as a counter electrode to the transparent electrode 11a. The back electrode 11b is either a cathode or an anode, and is usually provided on the substrate 13 as an anode. Examples of the forming material include metals such as gold, silver, and chromium. Therefore, the back electrode 11b can reflect light.

A bonding layer 17 is provided between the substrate 13 and the color filter 15 . The bonding layer 17 has translucency. As the material of the bonding layer 17 , any material used in a general OLED display device may be used. For example, a photocurable resin such as a photosensitive polyimide resin or a thermosetting resin may be used.

In addition to the structure shown in FIG. 1 , the OLED display panel 100 may also have structures of an OLED display panel such as a hole injection layer, a hole transport layer, an electron transport layer, a sealing layer, a touch sensor panel, etc. (omitted) icon).

The characteristic of the OLED display panel in FIG. 1 is that color filters are arranged on each of the OLED elements 12R, 12G, and 12B of a plurality of colors so as to face the colored layers 15R, 15G, and 15B of the same color respectively. Film 15. As shown in FIG. 1 , the white external light W passes through the red coloring layer 15R, and then passes through the transparent electrode 11 a and the red OLED layer 10R that emits red light, and is reflected at the back electrode 11 b , and then passes through the red OLED layer 10R and the transparent OLED layer 10R again. The electrode 11a and the red colored layer 15R reflect the light G into the eyes of the observer.

The green and blue colors of the external light W are absorbed by the red coloring layer 15R, so the light intensity becomes 1/3. In addition, since the reflected light G passes through the red coloring layer 15R and the red OLED layer 10R again, attenuation will occur. In addition, since the reflected light G is red, the red light emitted from the OLED layer 10R can be enhanced. The same situation applies when external light W is incident on the green coloring layer 15G and the blue coloring layer 15B, and the green light and the blue light can be enhanced respectively. Therefore, by using a color filter in an OLED display panel, even without using a circular polarizing plate for anti-reflection purposes, the reflection of external light can be greatly suppressed and the luminous brightness of the OLED element can be improved.

However, color filters are usually prone to interference spots resulting from regular two-dimensional structures. In addition, color filters have the problem of being easily reflected at the interface, resulting in a reduction in the lighting efficiency of the light emitted from the OLED element. In addition, the color filter has the following problems: compared with the case of using a circular polarizing plate, the ultraviolet absorption function is insufficient, and the OLED element is prone to deterioration over time due to ultraviolet light contained in external light (that is, the weather resistance is low). Furthermore, the color filter has a problem of insufficient impact absorption function compared to the case of using a circular polarizing plate.

In addition, the OLED display panel 100 of this embodiment has a microcavity structure. The light generated from the OLED layers 10R, 10G, and 10B is emitted to the outside through the transparent electrode 11a. Here, the emitted light includes: "direct light" that is emitted directly from the OLED layers 10R, 10G, and 10B toward the transparent electrode 11a, and "direct light" that is emitted from the OLED layers 10R, 10G, and 10B toward the back electrode 11b and is reflected by the back electrode 11b and then directed again. There are two components of "reflected light" of the transparent electrode 11a. That is, the first optical path C1 and the second optical path C2 are formed. In the first optical path C1, part of the light emitted from the OLED layers 10R, 10G, and 10B does not travel to the back electrode 11b side but travels to the transparent electrode 11a side. Through the transparent The electrode 11a emits to the outside; the second light path C2 mentioned above is the remaining part of the light emitted from the OLED layers 10R, 10G, and 10B that travels to the back electrode 11b side and is reflected by the back electrode 11b, and then passes through the OLED layers 10R, 10G, 10B and the transparent The electrode 11a is emitted to the outside. The OLED layers 10R, 10G, and 10B have different thicknesses to enhance the light components corresponding to each color through the interference of the direct light and the reflected light. That is, the thickness of each of the OLED layers 10R, 10G, and 10B is made different so that the optical path length between the back electrode (positive electrode) 11b and the transparent electrode (negative electrode) 11a is equal to the EL spectrum peak of each of red, green, and blue. The wavelengths are consistent to extract the strongest light from each color. Specifically, the thickness of the short-wavelength blue OLED layer 10B is designed to be thinner, and the thickness of the long-wavelength red OLED layer 10R is designed to be thicker. The light generated in the OLED layer is repeatedly reflected between the positive and negative electrodes. As a result, only the light of the wavelength consistent with the optical path length is strengthened by resonance, and the light of other wavelengths inconsistent with the optical path length is weakened. Thus, The spectrum of light extracted to the outside becomes steeper and more intense, and the brightness and color purity are improved. OLED display panels with a microcavity structure can achieve excellent effects of improving brightness and color purity. However, on the other hand, due to the steep spectrum, there may be a problem of strong viewing angle dependence (narrow viewing angle). Therefore, when the image is viewed diagonally during image display, color shift may occur, that is, the color may appear different from the color originally intended to be displayed.

(Optical element of the present invention) The optical element of the present invention is an optical element laminated on the viewing side of the OLED display device, and includes an adhesive layer, an adhesive layer, a resin layer, a glass layer, a hard coating layer, an anti-reflective layer, an anti-glare layer, and an intermediate layer ( At least one layer of compatible layer), impact absorption layer, antistatic layer, etc. However, the optical element of the present invention does not contain a polarizing plate or the like with a polarization degree exceeding 95%.

(adhesive layer) The adhesive layer refers to a layer that has adhesiveness at room temperature and is adhered to the adherend with light pressure. It also means that the adhesive layer remains functional even when the adherend attached to the adhesive layer is peeled off. The most adhering person.

From the viewpoint of effectively reducing color shift or interference spots in the OLED display device, the adhesive layer constituting the optical element of the present invention (hereinafter sometimes referred to as the "adhesive layer of the present invention") preferably has light scattering Characteristics (the function of scattering light). When the adhesive layer of the present invention has light scattering properties, it is preferable to include light-scattering fine particles dispersed in the adhesive layer.

When the OLED display device of the present invention includes a color filter on the viewing side and the adhesive layer has light scattering properties, the color shift or interference spots of the OLED display device can be reduced, and the defects of the OLED display device caused by light scattering can be suppressed. From the viewpoint of image blur, the distance (d) between the above-mentioned adhesive layer having light scattering properties and the above-mentioned color filter is preferably 700 μm or less. From the viewpoint of suppressing image blurring of the OLED display device caused by light scattering, the distance between the adhesive layer having light scattering characteristics and the color filter is more preferably 600 μm or less, and further preferably 500 μm or less. . Preferably, the adhesive layer with light scattering properties is directly connected to the color filter. The distance between the adhesive layer with light scattering properties and the color filter represents the distance (μm) between the surface of the adhesive layer in the direction of the color filter and the surface of the color filter in the direction of the adhesive layer. When there are other layers laminated between the adhesive layer with light scattering properties and the color filter, it is equivalent to the thickness (μm) of the other layers (total when there are two or more layers).

The haze value (H) of the adhesive layer of the present invention is not particularly limited. From the perspective of effectively reducing color shift or interference spots in the OLED display device, it is preferably 20% or more, and more preferably 30% or more. , more preferably 40% or more, particularly preferably 50% or more. Furthermore, from the viewpoint of suppressing image blurring of the OLED display device and displaying high-definition images, the haze value of the adhesive layer of the present invention is preferably 90% or less, more preferably 80% or less, and further preferably 70%. %the following.

The total light transmittance of the adhesive layer of the present invention is not particularly limited. From the perspective of ensuring the brightness of the OLED display device, it is preferably 60% or more, more preferably 70% or more, and further preferably 80% or more. Especially preferably, it is above 90%. In addition, the upper limit of the total light transmittance of the adhesive layer of the present invention is not particularly limited, and may be less than 100%, 99.9% or less, or 99% or less.

The haze value and total light transmittance of the adhesive layer of the present invention can be measured by the methods specified in JIS K 7136 and JIS K 7361 respectively. Depending on the type or thickness of the adhesive layer, the following light-scattering fine particles Control the type or blending amount.

From the perspective of effectively reducing color shift or interference spots in the OLED display device, the thickness (T) of the adhesive layer of the present invention is preferably 10 to 100 μm, more preferably 15 to 90 μm, and even more preferably 20～80 μm.

The light-scattering fine particles have an appropriate refractive index difference with the adhesive in the adhesive layer, thereby imparting light-scattering properties to the adhesive layer. It is preferable if the adhesive layer contains light-scattering microparticles because it imparts light-scattering properties. Examples of light-scattering fine particles include inorganic fine particles, polymer fine particles, and the like. Examples of the material of the inorganic fine particles include silicon oxide, calcium carbonate, aluminum hydroxide, magnesium hydroxide, clay, talc, titanium dioxide, and the like. Examples of the material of the polymer fine particles include silicone resin, acrylic resin, methacrylic resin (such as polymethylmethacrylate), polystyrene resin, polyurethane resin, and melamine resin. Polyethylene resin, epoxy resin, etc. The light-scattering microparticles are preferably polymer microparticles, especially microparticles composed of silicone resin (such as the TOSPEARL series manufactured by Momentive Advanced Materials Japan Co., Ltd.) which have excellent dispersion, stability and connection with the adhesive layer. The appropriate refractive index difference of the adhesive layer can obtain an adhesive layer with excellent scattering properties that displays uniform haze in the plane, which is more suitable for reducing color shifts or interference spots in OLED display devices. The shape of the light-scattering fine particles may be, for example, a true spherical shape, a flat shape, or an irregular shape. The light-scattering fine particles can be used alone or in combination of two or more types.

From the viewpoint of imparting appropriate light scattering characteristics to the adhesive layer, the volume average particle diameter of the light scattering fine particles is preferably 0.1 μm or more, more preferably 0.15 μm or more, further preferably 0.2 μm or more, still more preferably It is 0.25 μm or more, preferably 1 μm or more. Furthermore, from the viewpoint of preventing the haze value from becoming too high and displaying high-definition images, the volume average particle diameter of the light-scattering fine particles is preferably 12 μm or less, more preferably 10 μm or less, and still more preferably 8 μm. or less, particularly preferably 5 μm or less. The volume average particle diameter can be measured using a Coulter counter, for example.

The refractive index (n3) of the light-scattering fine particles is preferably 1.2 to 5, more preferably 1.25 to 4.5, and may be 1.3 to 4 or 1.35 to 3.

From the perspective of effectively reducing color shift or interference spots in OLED display devices, the refractive index of the light-scattering microparticles and the adhesive in the adhesive layer (the adhesive layer in the adhesive layer excluding the light-scattering microparticles) The absolute value of the difference is preferably 0.001 or more, more preferably 0.01 or more, further preferably 0.02 or more, particularly preferably 0.03 or more, and may be 0.04 or more, or 0.05 or more. Furthermore, from the viewpoint of preventing the haze value from becoming too high, suppressing image blur, and displaying a high-definition image, the absolute value of the difference in refractive index between the light-scattering fine particles and the adhesive is preferably 5 or less, and more preferably 4 or less, and more preferably 3 or less.

The refractive index (n2) of the above-mentioned adhesive is preferably 1.40 to 1.60, more preferably 1.42 to 1.55, further preferably 1.43 to 1.50. The refractive index of the above-mentioned adhesive can be adjusted according to the type or content of the following monomers containing aromatic rings, high refractive index organic materials, and high refractive inorganic materials.

From the viewpoint of imparting appropriate light scattering properties to the adhesive layer, the content of the light-scattering fine particles in the adhesive layer is preferably 0.01 part by weight or more, more preferably, based on 100 parts by weight of the adhesive constituting the adhesive layer. It is 0.05 part by weight or more, more preferably 0.1 part by weight or more, especially 0.15 part by weight or more. Furthermore, from the viewpoint of preventing the haze value from becoming too high, suppressing image blur, and displaying high-definition images, the content of the light-scattering fine particles is preferably 80 parts by weight based on 100 parts by weight of the adhesive constituting the adhesive layer. parts or less, more preferably 70 parts by weight or less.

The adhesive layer of the present invention (especially when a color filter is disposed on the viewing side of the OLED element, and the distance (d) between the adhesive layer of the present invention and the color filter is 700 μm or less) The adhesive layer of the present invention) is not particularly limited. From the perspective of preventing interface reflection and improving the lighting efficiency of the light emitted from the OLED element, the adhesive layer of the present invention is preferably of high refractive index. From the perspective of preventing interface reflection and improving the lighting efficiency of the light emitted from the OLED element, the refractive index of the adhesive layer of the present invention is preferably 1.57 or more, more preferably 1.575 or more, and further preferably 1.580 or more, especially Preferably it is 1.585 or more, more preferably 1.590 or more, and it may be 1.595 or more. The refractive index of the adhesive layer of the present invention can be adjusted according to the type or content of the following monomers containing aromatic rings, high refractive index organic materials, and high refractive inorganic materials.

The change ratio of the refractive index of the adhesive layer of the present invention before and after humidification is not particularly limited. This is from the perspective of preventing interface reflection even in high temperature and high humidity environments and stably increasing the lighting rate of light emitted from the OLED element. In other words, it is preferably 0.05 or less, more preferably 0.04 or less, further preferably 0.02 or less, and particularly preferably 0.01 or less. The change ratio of the refractive index of the adhesive layer of the present invention before and after humidification can be calculated by the following formula when the adhesive layer of the present invention is stored in a humidified environment at a temperature of 85°C and a relative humidity of 85% for 120 hours. The change ratio of the refractive index before and after humidification = | Initial refractive index - Refractive index after humidification | / (Initial refractive index) The change ratio of the refractive index before and after humidification can be determined by the type or content of the following aromatic ring-containing monomers, high refractive index organic materials, high refractive inorganic materials, the type of adhesive constituting the adhesive layer, monomer composition, and interaction. Adjust the joint degree, thickness, etc.

The adhesive constituting the adhesive layer of the present invention is not particularly limited. Examples thereof include: acrylic adhesive, rubber adhesive, vinyl alkyl ether adhesive, silicone adhesive, and polyester adhesive. , polyamide adhesives, urethane adhesives, fluorine adhesives, epoxy adhesives, etc. Among them, as the adhesive constituting the adhesive layer, an acrylic adhesive is preferred in terms of transparency, adhesiveness, weather resistance, cost, and ease of design of the adhesive. That is, the adhesive layer of the present invention is preferably an acrylic adhesive layer containing an acrylic adhesive. The above-mentioned adhesives can be used alone or in combination of two or more types.

The acrylic adhesive layer contains an acrylic polymer as a base polymer. The above-mentioned acrylic polymer is a polymer containing an acrylic monomer (a monomer having a (meth)acrylyl group in the molecule) as a monomer component constituting the polymer. The acrylic polymer is preferably a polymer containing alkyl (meth)acrylate as a monomer component constituting the polymer. In addition, an acrylic polymer can be used individually or in combination of 2 or more types.

The adhesive composition forming the adhesive layer of the present invention may be in any form. For example, the adhesive composition may be emulsion type, solvent type (solution type), active energy ray hardening type, hot melt type (hot melt type), etc. Among them, solvent-based or active energy ray-curing type adhesive compositions are preferred in terms of productivity and ease of obtaining an adhesive layer with excellent optical properties or appearance.

That is, the adhesive layer of the present invention is an acrylic adhesive layer containing an acrylic polymer as a base polymer, and is preferably formed of a solvent-based or active energy ray-curable acrylic adhesive composition.

Examples of the active energy rays include ionizing radiation such as α rays, β rays, γ rays, neutron rays, and electron beams, or ultraviolet rays. Ultraviolet rays are particularly preferred. That is, the active energy ray curable adhesive composition is preferably an ultraviolet curable adhesive composition.

Examples of the adhesive composition (acrylic adhesive composition) forming the acrylic adhesive layer include an acrylic adhesive composition containing an acrylic polymer as an essential component, or an acrylic adhesive composition constituting an acrylic polymer. A mixture of monomers (sometimes referred to as a "monomer mixture") or an acrylic adhesive composition whose partial polymer is an essential component, etc. Examples of the former include so-called solvent-based acrylic adhesive compositions. Examples of the latter include so-called active energy ray-curable acrylic adhesive compositions. The above-mentioned "monomer mixture" refers to a mixture containing monomer components constituting a polymer. In addition, the above-mentioned "partial polymer" may also be called "prepolymer" and refers to a composition in which one or more monomer components among the monomer components in the above-mentioned monomer mixture are partially polymerized.

The above-mentioned acrylic polymer is a polymer composed (formed) of an acrylic monomer as an essential monomer component (monomer component). The acrylic polymer is preferably a polymer composed (formed) of (meth)acrylic acid alkyl ester as an essential monomer component. That is, the acrylic polymer preferably contains alkyl (meth)acrylate as a structural unit. In this specification, "(meth)acrylic acid" means "acrylic acid" and/or "methacrylic acid" (either or both of "acrylic acid" and "methacrylic acid"), and the same applies to others. Furthermore, the above-mentioned acrylic polymer is composed of one type or two or more types of monomer components.

The alkyl (meth)acrylate that is an essential monomer component is preferably an alkyl (meth)acrylate having a linear or branched alkyl group. In addition, (meth)acrylic acid alkyl ester can be used individually or in combination of 2 or more types.

The alkyl (meth)acrylate having a linear or branched alkyl group is not particularly limited, and examples thereof include: (meth)acrylic acid methyl ester, (meth)acrylic acid ethyl ester, (meth)acrylic acid propyl ester Ester, isopropyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, second butyl (meth)acrylate, third butyl (meth)acrylate, ( Amyl methacrylate, isopentyl (meth)acrylate, hexyl (meth)acrylate, heptyl (meth)acrylate, octyl (meth)acrylate, 2-ethylhexyl (meth)acrylate Ester, isooctyl (meth)acrylate, nonyl (meth)acrylate, isononyl (meth)acrylate, decyl (meth)acrylate, isodecyl (meth)acrylate, (meth)acrylic acid Undecyl ester, dodecyl (meth)acrylate, tridecyl (meth)acrylate, myristyl (meth)acrylate, pentadecyl (meth)acrylate, Cetyl (meth)acrylate, heptadecyl (meth)acrylate, stearyl (meth)acrylate (stearyl (meth)acrylate), isostearyl (meth)acrylate Aliphatic esters, nonadecyl (meth)acrylate, eicosanyl (meth)acrylate, and other alkyl (meth)acrylates having a linear or branched chain alkyl group with 1 to 20 carbon atoms. Among them, the above-mentioned alkyl (meth)acrylate having a linear or branched alkyl group is preferably an alkyl (meth)acrylate having a linear or branched alkyl group having 4 to 18 carbon atoms, and more preferably Preferred ones are 2-ethylhexyl acrylate (2EHA) and isostearyl acrylate (ISTA). Moreover, the above-mentioned alkyl (meth)acrylate having a linear or branched alkyl group can be used alone or in combination of two or more kinds.

The ratio of the above-mentioned alkyl (meth)acrylate in all monomer components (100% by weight) constituting the above-mentioned acrylic polymer is not particularly limited, but is preferably 50% by weight or more (for example, 50 to 100% by weight). More preferably, it is 53-90 weight%, and still more preferably, it is 55-85 weight%.

The acrylic polymer may also contain the alkyl (meth)acrylate and a copolymerizable monomer as monomer components constituting the polymer. That is, the acrylic polymer may contain a copolymerizable monomer as a structural unit. In addition, a copolymerizable monomer can be used individually or in combination of 2 or more types.

The above-mentioned copolymerizable monomer is not particularly limited. In terms of obtaining an adhesive layer with a high refractive index, suppressing the interface reflection with the OLED display panel, and improving the lighting rate of the light from the OLED element, examples of molecules are preferably used. A monomer with an aromatic ring inside. That is, the acrylic polymer preferably contains a monomer having an aromatic ring in the molecule as a structural unit.

The monomer system having an aromatic ring in the molecule is a monomer having at least one aromatic ring in the molecule (within one molecule). In this specification, the above-mentioned "monomer having an aromatic ring in the molecule" may be referred to as "a monomer containing an aromatic ring".

As the monomer containing an aromatic ring, a compound containing at least one aromatic ring and at least one ethylenically unsaturated group in one molecule can be used. As the aromatic ring-containing monomer, one type of these compounds may be used alone or two or more types may be used in combination.

Examples of the ethylenically unsaturated group include (meth)acrylyl, vinyl, (meth)allyl, and the like. From the viewpoint of polymerization reactivity, a (meth)acryl group is preferred, and from the viewpoint of flexibility or adhesiveness, an acryl group is more preferred. From the viewpoint of suppressing a decrease in the flexibility of the adhesive, it is preferable to use a compound having 1 ethylenically unsaturated group in one molecule (that is, a monofunctional monomer) as the aromatic ring-containing monomer.

The number of aromatic rings contained in one molecule of a compound that can be used as a monomer containing an aromatic ring may be 1 or 2 or more. The upper limit of the number of aromatic rings contained in the aromatic ring-containing monomer is not particularly limited, but may be 16 or less, for example. From the viewpoint of ease of preparation of the acrylic polymer or transparency of the adhesive, the number of aromatic rings may be, for example, 12 or less, preferably 8 or less, more preferably 6 or less, 5 or less, or 4 It can be 3 or less or 2 or less.

The aromatic ring of the compound that can be used as a monomer containing an aromatic ring can be, for example, a benzene ring (which can be a benzene ring constituting a part of the biphenyl structure or the fluorine structure); naphthalene ring, indene ring, azulene ring, anthracene ring, The condensed ring of phenanthrene ring and other carbocyclic rings can also be, for example, pyridine ring, pyrimidine ring, pyridine ring, pyridine ring, tri-pyridine ring, pyrrole ring, pyrazole ring, imidazole ring, triazole ring, ethazole ring, isozoline ring, etc. Heterocyclic rings such as ethazole ring, thiazole ring, and thiophene ring. In the above-mentioned heterocyclic ring, the heteroatoms contained as ring-forming atoms may be, for example, one or more types selected from the group consisting of nitrogen, sulfur, and oxygen. The heteroatoms constituting the above heterocyclic ring may be one or both of nitrogen and sulfur. The monomer containing an aromatic ring may also have a structure in which one or more carbocyclic rings and one or more heterocyclic rings are condensed, such as a dinaphthothiophene structure.

The above-mentioned aromatic ring (preferably a carbocyclic ring) may have one or more substituents on the ring atoms, or may have no substituents. When it has a substituent, examples of the substituent include an alkyl group, an alkoxy group, an aryloxy group, a hydroxyl group, a halogen atom (fluorine atom, chlorine atom, bromine atom, etc.), a hydroxyalkyl group, and a hydroxyalkoxy group. , glycidoxy group, etc., but are not limited to these. Among the substituents containing carbon atoms, the number of carbon atoms contained in the substituent is preferably 1 to 4, more preferably 1 to 3, for example, it can be 1 or 2. The above-mentioned aromatic ring may have no substituents on the ring atoms, or may have one or more substituents selected from the group consisting of alkyl groups, alkoxy groups, and halogen atoms (such as bromine atoms). . Furthermore, the term "the aromatic ring of the aromatic ring-containing monomer has a substituent on its ring atom" means that the aromatic ring has a substituent other than the substituent having an ethylenically unsaturated group.

The aromatic ring and the ethylenically unsaturated group may be bonded directly or through a linking group. The above-mentioned linking group may be, for example, one or two selected from the group consisting of an alkylene group, an oxyalkylene group, a poly(oxyalkylene) group, a phenyl group, an alkylphenyl group, and an alkoxyphenyl group. One or more of two or more structural groups in which more than one hydrogen atom is substituted with a hydroxyl group (such as a hydroxyalkylene group), an oxygen group (-O- group), a sulfoxy group (-S- group), etc. The base of the structure. The aromatic ring and the ethylenically unsaturated group can preferably be bonded directly, or bonded through a linking group selected from the group consisting of an alkylene group, an oxyalkylene group and a poly(oxyalkylene) group. Structure of monomers containing aromatic rings. The number of carbon atoms in the above-mentioned alkylene group and the above-mentioned oxyalkylene group is preferably 1 to 4, more preferably 1 to 3, and may be 1 or 2, for example. The repeating number of the oxyalkylene units in the poly(oxyalkylene) group may be, for example, 2 to 3.

Examples of compounds that can be preferably used as aromatic ring-containing monomers include aromatic ring-containing (meth)acrylates and aromatic ring-containing vinyl compounds. The (meth)acrylate containing an aromatic ring and the vinyl compound containing an aromatic ring may be used individually by 1 type or in combination of 2 or more types. It is also possible to use one or more aromatic ring-containing (meth)acrylates in combination with one or more aromatic ring-containing vinyl compounds.

When the above-mentioned acrylic polymer contains the above-mentioned aromatic ring-containing monomer as a monomer component constituting the polymer, the above-mentioned aromatic ring-containing monomer in all monomer components constituting the above-mentioned acrylic polymer (100% by weight) The body ratio is not particularly limited, but it is preferably 30% by weight or more, more preferably 50% by weight or more, further preferably 60% by weight or more, and may be 70% by weight or more. If the above-mentioned ratio is 30% by weight or more, a higher refractive index tends to be easily obtained, so it is preferable. Furthermore, from the viewpoint of easily obtaining a high refractive index, the content of the aromatic ring-containing monomer may, for example, exceed 70% by weight, may be 75% by weight or more, may be 80% by weight or more, may be 85% by weight or more, It may be 90% by weight or more, or it may be 95% by weight or more. Furthermore, in order to obtain an adhesive layer having moderate flexibility and an adhesive layer having excellent transparency, the upper limit of the ratio of the aromatic ring-containing monomer is preferably 99% by weight or less, more preferably 98% by weight or less, more preferably 97% by weight or less, and 96% by weight or less. Furthermore, the content of the aromatic ring-containing monomer may be 93% by weight or less, 90% by weight or less, 80% by weight or less, or 75% by weight or less. In some aspects where more emphasis is placed on adhesive properties and/or optical properties, the content of the above-mentioned aromatic ring-containing monomer may be 70% by weight or less, may be 60% by weight or less, or may be 45% by weight or less.

As the aromatic ring-containing monomer, a monomer having two or more aromatic rings (preferably carbocyclic rings) in one molecule is preferably used in terms of easily obtaining a high refractive index-increasing effect. Examples of monomers having two or more aromatic rings in one molecule (hereinafter also referred to as "monomers containing multiple aromatic rings") include: two or more non-condensed aromatic rings via a linking group bond Monomers with a knotted structure, monomers with a structure in which two or more non-condensed aromatic rings are chemically bonded directly (i.e., not through other atoms), monomers with a condensed aromatic ring structure, monomers with a fluorine structure, Monomers with dinaphthothiophene structure, monomers with dibenzothiophene structure, etc. The monomer containing a plurality of aromatic rings can be used individually by 1 type or in combination of 2 or more types.

The above-mentioned linking group may be, for example, an oxygen group (-O-), a sulfoxy group (-S-), or an oxyalkylene group (such as -O-(CH ₂ ) _n -group, where n is 1 to 3, Preferably, it is 1), thioxyalkylene group (for example, -S-(CH ₂ ) _n -group, where n is 1 to 3, preferably 1), straight-chain alkylene group (that is, -(CH ₂ ) _n -group, where n is 1 to 6, preferably 1 to 3), the alkylene group in the above-mentioned oxyalkylene group, the above-mentioned thioxyalkylene group and the above-mentioned linear alkylene group is partially halogenated or Completely halogenated base, etc. From the viewpoint of flexibility of the adhesive, etc., preferred examples of the above-mentioned linking groups include oxygen groups, sulfoxy groups, oxyalkylene groups, and linear alkylene groups. Specific examples of the monomer having a structure in which two or more non-condensed aromatic rings are bonded via a linking group include: (meth)phenoxybenzyl acrylate (for example, (meth)acrylic m-phenoxy Benzyl ester), thiophenoxybenzyl (meth)acrylate, benzylbenzyl (meth)acrylate, etc.

The above-mentioned monomer having a structure in which two or more non-condensed aromatic rings are directly chemically bonded can be, for example, a (meth)acrylate containing a biphenyl structure, a (meth)acrylate containing a triphenyl structure, or a (meth)acrylate containing a vinyl group. biphenyl etc. Specific examples include o-phenylphenol (meth)acrylate, biphenylmethyl (meth)acrylate, and the like.

Examples of the monomer having a condensed aromatic ring structure include naphthalene ring-containing (meth)acrylate, anthracene ring-containing (meth)acrylate, vinyl-containing naphthalene, vinyl-containing anthracene, and the like. Specific examples include 1-naphthylmethyl (meth)acrylate (also known as 1-naphthylmethyl (meth)acrylate), hydroxyethylated β-naphthol acrylate, and (meth)acrylic acid. 2-naphthyl ethyl ester, 2-naphthyloxyethyl acrylate, 2-(4-methoxy-1-naphthyloxy)ethyl (meth)acrylate, etc.

Specific examples of the above-mentioned monomer having a fluorine structure include: 9,9-bis(4-hydroxyphenyl) fluorine (meth)acrylate, 9,9-bis[4-(2-hydroxyethoxy) Base) phenyl] fluorine (meth)acrylate, etc. Furthermore, since a monomer having a fluorine structure contains a structural part in which two benzene rings are directly chemically bonded, it is included in the above concept of a monomer having a structure in which two or more non-condensed aromatic rings are directly chemically bonded.

Examples of the above-mentioned monomer having a dinaphthothiophene structure include (meth)acrylyl group-containing dinaphthothiophene, vinyl group-containing dinaphthothiophene, and (meth)allyl group-containing dinaphthothiophene. And thiophene etc. Specific examples include: (meth)acryloxymethyldinaphthothiophene (for example, CH ₂ CH(R ¹ )C(O) bonded to the 5- or 6-position of the dinaphthothiophene ring Compounds with the structure of OCH ₂ -; here, R ¹ is a hydrogen atom or a methyl group), (meth)acryloxyethyl dinaphthothiophene (such as the 5- or 6-position bond in the dinaphthothiophene ring Compounds with the structure of CH ₂ CH(R ¹ )C(O)OCH(CH ₃ )- or CH ₂ CH(R ¹ )C(O)OCH ₂ CH ₂ -; here, R ¹ is a hydrogen atom or Methyl), vinyl dinaphthothiophene (for example, a compound with a vinyl group bonded to the 5- or 6-position of the naphthothiophene ring), (meth)allyloxy dinaphthothiophene, etc. Furthermore, since the monomer having a dinaphthothiophene structure contains a naphthalene structure and also has a structure in which a thiophene ring is condensed with two naphthalene structures, it is also included in the concept of the above-mentioned monomer having a condensed aromatic ring structure.

Examples of the monomer having a dibenzothiophene structure include (meth)acrylyl group-containing dibenzothiophene, vinyl group-containing dibenzothiophene, and the like. Furthermore, since the monomer having a dibenzothiophene structure has a structure in which a thiophene ring is condensed with two benzene rings, it is included in the concept of the above-mentioned monomer having a condensed aromatic ring structure. Furthermore, neither the dinaphthothiophene structure nor the dibenzothiophene structure is a structure in which more than two non-condensed aromatic rings are directly chemically bonded.

As the monomer containing an aromatic ring, a monomer having one aromatic ring (preferably a carbocyclic ring) in one molecule can also be used. A monomer having one aromatic ring in one molecule can, for example, contribute to improving the flexibility of the adhesive, adjusting the adhesive properties, improving transparency, etc. From the viewpoint of increasing the refractive index of the adhesive, a monomer containing one aromatic ring per molecule is preferably used in combination with a monomer containing a plurality of aromatic rings.

Examples of monomers having one aromatic ring in one molecule include: (meth)acrylic acid benzyl ester, (meth)acrylic acid methoxybenzyl ester, (meth)acrylic acid phenyl ester, ethoxylated phenol ( Meth)acrylate, phenoxypropyl (meth)acrylate, phenoxybutyl (meth)acrylate, tolyl (meth)acrylate, 2-hydroxy-3-phenoxy (meth)acrylate (Meth)acrylate containing aromatic rings such as chlorobenzyl (meth)acrylate and chlorobenzyl (meth)acrylate; (meth)acrylate 2-(4,6-dibromo-2-butylphenoxy) Ethyl ester, 2-(4,6-dibromo-2-isopropylphenoxy)ethyl (meth)acrylate, 6-(4,6-dibromo-2-butyl(meth)acrylate) phenoxy)hexyl ester, 6-(4,6-dibromo-2-isopropylphenoxy)hexyl (meth)acrylate, 2,6-dibromo-4-nonylphenyl acrylate, 2,6-dibromo-4-dodecylphenyl acrylate and other bromine-substituted aromatic ring-containing (meth)acrylates; styrene, α-methylstyrene, vinyltoluene, tert-butylstyrene Vinyl compounds containing carbon aromatic rings; heteroaromatic compounds such as N-vinylpyridine, N-vinylpyrimidine, N-vinylpyridine, N-vinylpyrrole, N-vinylimidazole, N-vinyl㗁azole, etc. Compounds with vinyl substituents on the ring, etc.

As the aromatic ring-containing monomer, it is also possible to use a monomer having a structure in which an oxyethylene chain is interposed between the ethylenically unsaturated group and the aromatic ring among the above-mentioned various aromatic ring-containing monomers. The monomer with an oxyethylene chain interposed between the ethylenically unsaturated group and the aromatic ring can be understood as the ethoxylate of the original monomer. The repeat number of the oxyethylene unit (-CH ₂ CH ₂ O-) in the above-mentioned oxyethylene chain is typically 1 to 4, preferably 1 to 3, more preferably 1 to 2, for example, 1. Specific examples of the ethoxylated aromatic ring-containing monomer include: ethoxylated o-phenylphenol (meth)acrylate, ethoxylated nonylphenol (meth)acrylate, ethoxylated cresol (meth)acrylate acrylate, phenoxyethyl (meth)acrylate, phenoxydiethylene glycol di(meth)acrylate, etc.

The content of the monomer containing multiple aromatic rings in the monomer containing aromatic rings is not particularly limited. For example, it may be 5% by weight or more, 25% by weight or more, or 40% by weight or more. From the viewpoint of easily realizing an adhesive with a higher refractive index, the content of the monomer containing a plurality of aromatic rings in the monomer containing an aromatic ring can be, for example, 50% by weight or more, preferably 70% by weight or more. It may be 85% by weight or more, it may be 90% by weight or more, or it may be 95% by weight or more. Substantially 100% by weight of the monomers containing aromatic rings may also be monomers containing multiple aromatic rings. That is, as the aromatic ring-containing monomer, only one type or two or more types of monomers containing a plurality of aromatic rings may be used. Furthermore, for example, considering the balance between high refractive index and adhesive properties and/or optical properties, the content of the monomer containing multiple aromatic rings in the monomer containing aromatic rings may be less than 100% by weight, and may be 98% by weight. It may be 90% by weight or less, 80% by weight or less, or 65% by weight or less. Taking into account the adhesive properties and/or optical properties, the content of the monomer containing a plurality of aromatic rings in the monomer containing aromatic rings may be 70% by weight or less, may be 50% by weight or less, may be 25% by weight or less, or It may be 10% by weight or less. An aspect can also be implemented in which the content of the monomer containing a plurality of aromatic rings in the monomer containing an aromatic ring is less than 5% by weight. It is also not necessary to use monomers containing multiple aromatic rings.

When the above-mentioned acrylic polymer contains the above-mentioned monomer containing a plurality of aromatic rings as a monomer component constituting the polymer, the above-mentioned monomer component containing a plurality of aromatic rings in all monomer components (100% by weight) constituting the above-mentioned acrylic polymer The ratio of the aromatic ring monomers is not particularly limited, but is preferably 3% by weight or more, more preferably 10% by weight or more, and still more preferably 25% by weight or more. If the above-mentioned ratio is 3% by weight or more, a higher refractive index tends to be easily obtained, so it is preferable. Furthermore, from the viewpoint of easily obtaining a high refractive index, the content of the monomer containing a plurality of aromatic rings may, for example, exceed 35% by weight, may be 50% by weight or more, may be 70% by weight or more, may be 75% by weight. It may be 85% by weight or more, 90% by weight or more, or 95% by weight or more. Furthermore, from the viewpoint of achieving a well-balanced combination of high refractive index, adhesive properties and/or optical properties, the upper limit of the ratio of the monomer containing a plurality of aromatic rings is preferably 99% by weight or less, more preferably 98% by weight. It may be 96% by weight or less, more preferably 96% by weight or less, it may be 93% by weight or less, it may be 90% by weight or less, it may be 85% by weight or less, it may be 80% by weight or less, or it may be 75% by weight or less. In addition, from the viewpoint of adhesive properties and/or optical properties, the content of the above-mentioned monomer containing a plurality of aromatic rings may be 70% by weight or less, may be 50% by weight or less, may be 25% by weight or less, may be 15% by weight or less. % by weight or less, and may be 5% by weight or less.

The above-mentioned copolymerizable monomer is not particularly limited, but in terms of suppression of clouding in a high-humidity environment, improvement of durability, compatibility with various additives such as ultraviolet absorbers, and transparency, examples of the copolymerizable monomer are preferably exemplified. Monomers with nitrogen atoms in the molecule and monomers with hydroxyl groups in the molecule. That is, the acrylic polymer preferably contains a monomer having a nitrogen atom in the molecule as a structural unit. Furthermore, the acrylic polymer preferably contains a monomer having a hydroxyl group in the molecule as a structural unit.

The monomer having a nitrogen atom in the molecule is a monomer having at least one nitrogen atom in the molecule (in one molecule). In this specification, the above-mentioned "monomer having a nitrogen atom in the molecule" may be referred to as a "nitrogen atom-containing monomer". The above-mentioned nitrogen atom-containing monomer is not particularly limited, and preferred examples include cyclic nitrogen-containing monomers, (meth)acrylamides, and the like. Furthermore, the nitrogen atom-containing monomer can be used alone or in combination of two or more types.

The above-mentioned cyclic nitrogen-containing monomer is not particularly limited as long as it has a polymerizable functional group having an unsaturated double bond, such as a (meth)acryl group or a vinyl group, and has a cyclic nitrogen structure. The above-mentioned cyclic nitrogen structure preferably has a nitrogen atom in the cyclic structure.

Examples of the cyclic nitrogen-containing monomer include N-vinyl cyclic amide (lactam vinyl monomer), vinyl monomers having nitrogen-containing heterocycles, and the like.

Examples of the N-vinyl cyclic amide include N-vinyl cyclic amide represented by the following formula (1). [Chemical 1] (In formula (1), R ¹ represents a divalent organic group)

R ¹ in the above formula (1) is a divalent organic group, preferably a divalent saturated hydrocarbon group or an unsaturated hydrocarbon group, more preferably a divalent saturated hydrocarbon group (such as an alkylene group with 3 to 5 carbon atoms, etc.) .

Examples of the N-vinyl cyclic amide represented by the above formula (1) include N-vinyl-2-pyrrolidone, N-vinyl-2-piperidone, N-vinyl- 3-morpholinone, N-vinyl-2-caprolactamine, N-vinyl-1,3-㗁𠯤-2-one, N-vinyl-3,5-morpholindione, etc.

Examples of the vinyl monomer having a nitrogen-containing heterocycle include acrylic monomers having a nitrogen-containing heterocycle, such as a morpholine ring, a piperidine ring, a pyrrolidine ring, a piperidine ring, and the like.

The above-mentioned vinyl monomer having a nitrogen-containing heterocycle is not particularly limited, and examples thereof include: (meth)acryloylmorpholine, N-vinylpiperone, N-vinylpyrrole, N-vinylimidazole, N -Vinylpyridine, N-vinylmorpholine, N-vinylpyrazole, vinylpyridine, vinylpyrimidine, vinylethazole, vinylisothiazole, vinylthiazole, vinylisothiazole, vinyl Acrylic acid, (meth)acrylylpyrrolidine, (meth)acrylylpyrrolidine, (meth)acrylylpiperidine, etc.

As the above-mentioned vinyl monomer having a nitrogen-containing heterocyclic ring, preferred is an acrylic monomer having a nitrogen-containing heterocyclic ring, and more preferred are (meth)acryloylmorpholine, (meth)acrylylpyrrolidine, (Meth)Acrylylpiperidine.

Examples of the (meth)acrylamides include (meth)acrylamide, N-alkyl(meth)acrylamide, N,N-dialkyl(meth)acrylamide, and the like. . Examples of the N-alkyl(meth)acrylamide include N-ethyl(meth)acrylamide, N-isopropyl(meth)acrylamide, N-n-butyl( Meth)acrylamide, N-octyl(meth)acrylamide, etc. Furthermore, the above-mentioned N-alkyl (meth)acrylamide also includes dimethylaminoethyl (meth)acrylamide, diethylaminoethyl (meth)acrylamide, and dimethylaminopropyl (Meth)acrylamide, such as (meth)acrylamide, has an amine group. Examples of the N,N-dialkyl(meth)acrylamide include N,N-dimethyl(meth)acrylamide and N,N-diethyl(meth)acrylamide. , N,N-dipropyl(meth)acrylamide, N,N-diisopropyl(meth)acrylamide, N,N-di(n-butyl)(meth)acrylamide, N,N-di(tert-butyl)(meth)acrylamide, etc.

In addition, the above-mentioned (meth)acrylamides also include various N-hydroxyalkyl (meth)acrylamides, for example. Examples of the above-mentioned N-hydroxyalkyl(meth)acrylamide include N-hydroxymethyl(meth)acrylamide, N-(2-hydroxyethyl)(meth)acrylamide, N-(2-hydroxyethyl)(meth)acrylamide, -Hydroxypropyl)(meth)acrylamide, N-(1-hydroxypropyl)(meth)acrylamide, N-(3-hydroxypropyl)(meth)acrylamide, N-( 2-Hydroxybutyl)(meth)acrylamide, N-(3-hydroxybutyl)(meth)acrylamide, N-(4-hydroxybutyl)(meth)acrylamide, N- Methyl-N-2-hydroxyethyl (meth)acrylamide, etc.

In addition, the above-mentioned (meth)acrylamides also include various N-alkoxyalkyl (meth)acrylamides, for example. Examples of the N-alkoxyalkyl(meth)acrylamide include N-methoxymethyl(meth)acrylamide and N-butoxymethyl(meth)acrylamide. wait.

In addition, examples of nitrogen atom-containing monomers other than the above-mentioned cyclic nitrogen-containing monomers and the above-mentioned (meth)acrylamides include: amine group-containing monomers, cyano group-containing monomers, and Imide-based monomers, isocyanate-containing monomers, etc. Examples of the above-mentioned amino group-containing monomer include aminoethyl (meth)acrylate, dimethylaminoethyl (meth)acrylate, dimethylaminopropyl (meth)acrylate, and (meth)acrylate. ) tert-butylaminoethyl acrylate, etc. Examples of the cyano group-containing monomer include acrylonitrile, methacrylonitrile, and the like. Examples of the above-mentioned acyl imine group-containing monomers include: maleimine-based monomers (such as N-cyclohexyl maleimide, N-isopropyl maleimide, N-lauryl Maleimide, N-phenylmaleimide, etc.), itonimide-based monomers (such as N-methyl itonimide, N-ethyl itonimide, n-butyl Ikonimide, N-octylicotimide, N-2-ethylhexylicotrimide, N-laurylicotrimide, N-cyclohexylicotrimide, etc. ), succinimide-based monomers (such as N-(meth)acryloxymethylenesuccinimide, N-(meth)acryloxy-6-oxyhexamethylenebutane Diimide, N-(meth)acryl-8-oxyoctamethylenesuccinimide, etc.). Examples of the isocyanate group-containing monomer include 2-(meth)acryloyloxyethyl isocyanate.

Among them, as the above-mentioned nitrogen atom-containing monomer, a cyclic nitrogen-containing monomer is preferred, and an N-vinyl cyclic amide is more preferred. More specifically, N-vinyl-2-pyrrolidone (NVP) is particularly preferred.

When the acrylic polymer contains the nitrogen-containing monomer as a monomer component constituting the polymer, the nitrogen-containing monomer in all monomer components (100% by weight) constituting the acrylic polymer The ratio of the body is not particularly limited, but it is preferably 1% by weight or more, more preferably 3% by weight or more, and still more preferably 5% by weight or more. If the above-mentioned ratio is 1% by weight or more, it is possible to further improve the suppression of clouding and durability in a high-humidity environment, so it is preferable. Furthermore, in order to obtain an adhesive layer having moderate flexibility and an adhesive layer having excellent transparency, the upper limit of the ratio of the nitrogen atom-containing monomer is preferably 30% by weight or less, more preferably 25% by weight or less, more preferably 20% by weight or less.

The above-mentioned monomer having a hydroxyl group in the molecule is a monomer having at least one hydroxyl group (hydroxyl) in the molecule (within one molecule). Preferably, it has an unsaturated double bond such as a (meth)acrylyl group or a vinyl group. The polymerizable functional group has a hydroxyl group. However, the above-mentioned monomers having a hydroxyl group in the molecule do not include the above-mentioned monomers containing nitrogen atoms. That is, in this specification, a monomer having both a nitrogen atom and a hydroxyl group in the molecule is included in the above-mentioned "nitrogen atom-containing monomer". In this specification, the above-mentioned "monomer having a hydroxyl group in the molecule" may be referred to as a "hydroxyl-containing monomer". Furthermore, the hydroxyl group-containing monomer can be used alone or in combination of two or more types.

Examples of the hydroxyl-containing monomer include: (meth)acrylic acid 2-hydroxyethyl ester, (meth)acrylic acid 2-hydroxypropyl ester, (meth)acrylic acid 3-hydroxypropyl ester, (meth)acrylic acid 3-hydroxypropyl 4-hydroxybutyl acrylate, 6-hydroxyhexyl (meth)acrylate, hydroxyoctyl (meth)acrylate, hydroxydecyl (meth)acrylate, hydroxylauryl (meth)acrylate, (meth)acrylic acid (4-Hydroxymethylcyclohexyl) ester and other hydroxyl-containing (meth)acrylates; vinyl alcohol; allyl alcohol, etc.

Among them, as the above-mentioned hydroxyl-containing monomer, hydroxyl-containing (meth)acrylate is preferred, and 2-hydroxyethyl acrylate (HEA) and 4-hydroxybutyl acrylate (4HBA) are more preferred.

When the above-mentioned acrylic polymer contains the above-mentioned hydroxyl-containing monomer as a monomer component constituting the polymer, the proportion of the above-mentioned hydroxyl-containing monomer in the total monomer components (100% by weight) constituting the above-mentioned acrylic polymer The ratio is not particularly limited, but from the viewpoint of suppressing clouding in a high-humidity environment and improving durability, it is preferably 0.5% by weight or more, more preferably 0.8% by weight or more, and still more preferably 1% by weight or more. Furthermore, in order to obtain an adhesive layer with moderate flexibility and an adhesive layer with excellent transparency, the upper limit of the ratio of the above-mentioned hydroxyl-containing monomer is preferably 30% by weight or less, more preferably 25%. % by weight or less, and more preferably 15% by weight or less.

The total ratio of the nitrogen atom-containing monomer and the hydroxyl group-containing monomer in all the monomer components (100% by weight) constituting the acrylic polymer is not particularly limited. In terms of suppression and durability improvement, the content is preferably 1% by weight or more, more preferably 5% by weight or more, and still more preferably 10% by weight or more. Furthermore, in order to obtain an adhesive layer having moderate flexibility and an adhesive layer having excellent transparency, the upper limit of the total of the above ratios is preferably 50% by weight or less, more preferably 40% by weight or less. Furthermore, it is more preferable that it is 35 weight% or less.

Examples of copolymerizable monomers other than nitrogen atom-containing monomers and hydroxyl group-containing monomers include monomers containing an alicyclic structure. The above-mentioned monomer containing an alicyclic structure is not particularly limited as long as it has a polymerizable functional group having an unsaturated double bond such as a (meth)acryl group or a vinyl group and has an alicyclic structure. For example, alkyl (meth)acrylate having a cycloalkyl group is included in the above-mentioned monomer containing an alicyclic structure. In addition, the monomer containing an alicyclic structure can be used individually or in combination of 2 or more types.

The alicyclic structure in the above-mentioned monomer containing an alicyclic structure is a cyclic hydrocarbon structure, preferably having a carbon number of 5 or more, more preferably a carbon number of 6 to 24, further preferably a carbon number of 6 to 15, and particularly preferably Carbon number 6 to 10.

Examples of the monomer containing an alicyclic structure include: (meth)cyclopropyl acrylate, (meth)cyclobutyl acrylate, (meth)cyclopentyl acrylate, and (meth)cyclohexyl acrylate. , cycloheptyl (meth)acrylate, cyclooctyl (meth)acrylate, isocamphenyl (meth)acrylate, dicyclopentyl (meth)acrylate, HPMPA represented by the following formula (2), the following Acrylic monomers such as TMA-2 represented by formula (3) and HCPA represented by the following formula (4). In addition, in the following formula (4), the bonding position between the cyclohexyl ring connected by a line and the structural formula in the parentheses is not particularly limited. Among these, isocamphenyl (meth)acrylate is preferred. [Chemicalization 2] [Chemical 3] [Chemical 4]

When the acrylic polymer contains the alicyclic structure-containing monomer as a monomer component constituting the polymer, the alicyclic structure-containing monomer in all monomer components (100% by weight) constituting the acrylic polymer The ratio of monomers is not particularly limited, but in terms of durability improvement, it is preferably 10% by weight or more. Furthermore, in order to obtain an adhesive layer having moderate flexibility, the upper limit of the ratio of the alicyclic structure-containing monomer is preferably 50% by weight or less, more preferably 40% by weight or less, and still more preferably 30% by weight. weight% or less.

Furthermore, examples of copolymerizable monomers include polyfunctional monomers. Examples of the polyfunctional monomer include: hexylene glycol di(meth)acrylate, butylene glycol di(meth)acrylate, (poly)ethylene glycol di(meth)acrylate, (poly)ethylene glycol di(meth)acrylate, Polypropylene glycol di(meth)acrylate, neopentyl glycol di(meth)acrylate, pentaerythritol di(meth)acrylate, pentaerythritol tri(meth)acrylate, dipentaerythritol hexa(meth)acrylate , trimethylolpropane tri(meth)acrylate, tetramethylolmethane tri(meth)acrylate, allyl (meth)acrylate, vinyl (meth)acrylate, divinylbenzene, cyclic Oxy acrylate, polyester acrylate, urethane acrylate, etc. In addition, a polyfunctional monomer can be used individually or in combination of 2 or more types.

When the above-mentioned acrylic polymer contains the above-mentioned polyfunctional monomer as a monomer component constituting the polymer, the proportion of the above-mentioned polyfunctional monomer in all monomer components (100% by weight) constituting the above-mentioned acrylic polymer The ratio is not particularly limited, but is preferably 0.5% by weight or less (for example, more than 0% by weight and less than 0.5% by weight), more preferably 0.2% by weight or less (for example, more than 0% by weight and less than 0.2% by weight).

Examples of the copolymerizable monomer include alkoxyalkyl (meth)acrylate. The above-mentioned alkoxyalkyl (meth)acrylate is not particularly limited, and examples thereof include: (meth)acrylic acid 2-methoxyethyl ester, (meth)acrylic acid 2-ethoxyethyl ester, (meth)acrylic acid 2-ethoxyethyl ester, Methoxytriethylene glycol acrylate, 3-methoxypropyl (meth)acrylate, 3-ethoxypropyl (meth)acrylate, 4-methoxybutyl (meth)acrylate , 4-ethoxybutyl (meth)acrylate, etc. Among them, the above-mentioned alkoxyalkyl (meth)acrylate is preferably alkoxyalkyl acrylate, and more preferably 2-methoxyethyl acrylate (MEA). In addition, the said alkoxyalkyl (meth)acrylate can be used individually or in combination of 2 or more types.

When the above-mentioned acrylic polymer contains the above-mentioned (meth)acrylic acid alkoxyalkyl ester as a monomer component constituting the polymer, the above-mentioned (meth)acrylic acid alkyl ester and the above-mentioned (meth)acrylic acid alkoxy group The ratio of the alkyl ester is not particularly limited, but it is preferably more than 100:0 and not more than 25:75 in terms of [former: latter] (weight ratio), more preferably more than 100:0 and not more than 50:50.

Examples of the copolymerizable monomer include carboxyl group-containing monomers, epoxy group-containing monomers, sulfonic acid group-containing monomers, phosphoric acid group-containing monomers, and aromatic hydrocarbon group-containing monomers. base) acrylates, vinyl esters, aromatic vinyl compounds, olefins or dienes, vinyl ethers, vinyl chloride, etc. Examples of the above-mentioned carboxyl group-containing monomer include: (meth)acrylic acid, itaconic acid, maleic acid, fumaric acid, crotonic acid, methacrylic acid, etc.; and, the above-mentioned carboxyl group-containing monomer Monomers also include monomers containing acid anhydride groups such as maleic anhydride and itaconic anhydride. Examples of the epoxy group-containing monomer include glycidyl (meth)acrylate, methylglycidyl (meth)acrylate, and the like. Examples of the sulfonic acid group-containing monomer include sodium vinyl sulfonate and the like. Examples of the (meth)acrylate having an aromatic hydrocarbon group include phenyl (meth)acrylate, phenoxyethyl (meth)acrylate, and benzyl (meth)acrylate. Examples of the vinyl esters include vinyl acetate, vinyl propionate, and the like. Examples of the aromatic vinyl compound include styrene, vinyltoluene, and the like. Examples of the olefins or dienes include ethylene, propylene, butadiene, isoprene, isobutylene, and the like. Examples of the vinyl ethers include vinyl alkyl ethers and the like.

When the adherend of the adhesive layer is wiring containing metal or metal oxide such as a touch panel, in terms of obtaining an acrylic adhesive layer with excellent corrosion resistance, the above-mentioned acrylic polymer is relatively Preferably, it does not contain or substantially contains no monomers containing acidic groups as monomer components constituting the polymer, and particularly preferably does not contain or substantially contains no monomers containing carboxyl groups. Examples of the acidic group-containing monomer include carboxyl group-containing monomers, sulfonic acid group-containing monomers, and phosphate group-containing monomers. Specifically, it can be considered that the ratio of the acidic group-containing monomer in all the monomer components (100% by weight) constituting the acrylic polymer is 0.05% by weight or less (preferably 0.01% by weight or less). Contains monomers containing acidic groups.

The content of the base polymer (especially acrylic polymer) in the adhesive layer of the present invention is not particularly limited. It is preferably 50% by weight or more (for example, 100% by weight of the total weight of the adhesive layer of the present invention). 50 to 100% by weight), more preferably 80% by weight or more (for example, 80 to 100% by weight), and still more preferably 90% by weight or more (for example, 90 to 100% by weight).

The base polymer such as the above-mentioned acrylic polymer contained in the adhesive layer of the present invention can be obtained by polymerizing monomer components. The polymerization method is not particularly limited, and examples thereof include a solution polymerization method, an emulsion polymerization method, a block polymerization method, a polymerization method based on active energy ray irradiation (active energy ray polymerization method), and the like. Among them, in terms of transparency and cost of the adhesive layer, the solution polymerization method and the active energy ray polymerization method are preferred.

In addition, various common solvents can also be used during the polymerization of the above-mentioned monomer components. Examples of the solvent include esters such as ethyl acetate and n-butyl acetate; aromatic hydrocarbons such as toluene and benzene; aliphatic hydrocarbons such as n-hexane and n-heptane; cyclohexane and methylcyclohexane; alicyclic hydrocarbons such as alkanes; organic solvents such as ketones such as methyl ethyl ketone and methyl isobutyl ketone. In addition, a solvent can be used individually or in combination of 2 or more types.

When polymerizing the above monomer components, a polymerization initiator such as a thermal polymerization initiator or a photopolymerization initiator (photoinitiator) may be used depending on the type of polymerization reaction. In addition, a polymerization initiator can be used individually or in combination of 2 or more types.

The above thermal polymerization initiator is not particularly limited, and examples thereof include: azo polymerization initiators, peroxide polymerization initiators (such as dibenzoyl peroxide, peroxymaleic acid tertiary acid). butyl ester, etc.), redox polymerization initiator, etc. Among them, the azo polymerization initiator disclosed in Japanese Patent Application Laid-Open No. 2002-69411 is preferred. Examples of the azo polymerization initiator include 2,2'-azobisisobutyronitrile (hereinafter sometimes referred to as "AIBN") and 2,2'-azobis-2-methylbutyronitrile. (hereinafter sometimes referred to as "AMBN"), 2,2'-azobis(2-methylpropionate)dimethyl ester, 4,4'-azobis-4-cyanovaleric acid, etc. In addition, the thermal polymerization initiator can be used individually or in combination of 2 or more types.

When the above-mentioned azo polymerization initiator is used in the polymerization of the above-mentioned acrylic polymer, the usage amount of the above-mentioned azo polymerization initiator is not particularly limited. The body composition is preferably 0.05 parts by weight or more, more preferably 0.1 parts by weight or more, and preferably 0.5 parts by weight or less, more preferably 0.3 parts by weight or less per 100 parts by weight.

The above-mentioned photopolymerization initiator is not particularly limited, and examples thereof include benzoin ether-based photopolymerization initiator, acetophenone-based photopolymerization initiator, α-ketool-based photopolymerization initiator, and aromatic sulfonyl initiator. Chlorine-based photopolymerization initiator, photoactive oxime-based photopolymerization initiator, benzoin-based photopolymerization initiator, benzoyl-based photopolymerization initiator, benzophenone-based photopolymerization initiator, ketal-based photopolymerization initiator Photopolymerization initiator, 9-oxosulfide𠮿 It is a photopolymerization initiator, etc. Examples of the acylphosphine oxide-based photopolymerization initiator and titanocene-based photopolymerization initiator may also be used. Examples of the benzoin ether photopolymerization initiator include benzoin methyl ether, benzoin ethyl ether, benzoin propyl ether, benzoin isopropyl ether, benzoin isobutyl ether, and 2,2-dimethoxy-1,2-di Phenylethane-1-one, anisole methyl ether, etc. Examples of the acetophenone-based photopolymerization initiator include 2,2-diethoxyacetophenone, 2,2-dimethoxy-2-phenylacetophenone, and 1-hydroxycyclohexyl Phenyl ketone, 4-phenoxydichloroacetophenone, 4-(tert-butyl)dichloroacetophenone, etc. Examples of the α-ketool photopolymerization initiator include 2-methyl-2-hydroxypropiophenone, 1-[4-(2-hydroxyethyl)phenyl]-2-methylpropane- 1-Keto etc. Examples of the aromatic sulfonyl chloride-based photopolymerization initiator include 2-naphthalene sulfonyl chloride and the like. Examples of the photoactive oxime-based photopolymerization initiator include 1-phenyl-1,1-propanedione-2-(O-ethoxycarbonyl)-oxime. Examples of the benzoin-based photopolymerization initiator include benzoin and the like. Examples of the benzilyl-based photopolymerization initiator include benzilyl and the like. Examples of the benzophenone-based photopolymerization initiator include benzophenone, benzoyl benzoic acid, 3,3'-dimethyl-4-methoxybenzophenone, and polyethylene. Benzophenone, α-hydroxycyclohexyl phenyl ketone, etc. Examples of the ketal-based photopolymerization initiator include benzyl dimethyl ketal and the like. As the above 9-oxosulfide𠮿 It is a photopolymerization initiator, for example: 9-oxosulfide , 2-chloro-9-oxosulfide𠮿 , 2-Methyl-9-oxosulfide𠮿 , 2,4-dimethyl-9-oxosulfide𠮿 , isopropyl-9-oxosulfide𠮿 , 2,4-diisopropyl-9-oxysulfide𠮿 , dodecyl-9-oxosulfide𠮿 wait. Examples of the above-mentioned acylphosphine oxide-based photopolymerization initiator include: 2,4,6-trimethylbenzoyldiphenylphosphine oxide, bis(2,4,6-trimethylbenzyl acyl)-phenylphosphine oxide, etc. Examples of the titanocene-based photopolymerization initiator include bis(eta ⁵ -2,4-cyclopentadien-1-yl)-bis(2,6-difluoro-3-(1H-pyrrole) -1-yl)-phenyl) titanium, etc. In addition, a photopolymerization initiator can be used individually or in combination of 2 or more types.

When the above-mentioned photopolymerization initiator is used in the polymerization of the above-mentioned acrylic polymer, the usage amount of the above-mentioned photopolymerization initiator is not particularly limited, for example, based on 100 weight of all monomer components constituting the above-mentioned acrylic polymer. parts, preferably 0.01 parts by weight or more, more preferably 0.1 parts by weight or more, and preferably 3 parts by weight or less, more preferably 1.5 parts by weight or less.

The adhesive layer of the present invention (especially when a color filter is disposed on the viewing side of the OLED element, and the distance (d) between the adhesive layer of the present invention and the color filter is 700 μm or less) The adhesive layer of the present invention) is not particularly limited, but preferably contains a high refractive index organic material. If the adhesive layer of the present invention contains a high refractive index organic material, it is better to obtain an adhesive layer with a high refractive index, suppress interface reflection with the OLED display panel, and improve the lighting efficiency of the light from the OLED element. In addition, the high refractive index organic material can be used alone or in combination of two or more types.

High refractive index organic material means that it is an organic material with high refractive index (High Refractive index). By combining such a high refractive index organic material with an acrylic polymer, it is possible to achieve an appropriate combination of refractive index, adhesive properties (peel strength, flexibility, etc.) and/or optical properties (total light transmittance, haze) value, etc.) adhesive. Organic materials that can be used as high refractive index organic materials can be polymers or non-polymers. Moreover, it may or may not have a polymerizable functional group.

The refractive index of the high refractive index organic material can be set within an appropriate range based on the relative relationship with the refractive index of the acrylic polymer, and is therefore not limited to a specific range. The refractive index of the high-refractive-index organic material is, for example, over 1.50, over 1.55, or over 1.57, and is preferably higher than the refractive index of the acrylic polymer. From the viewpoint of increasing the refractive index of the adhesive, the refractive index of the high-refractive index organic material is preferably 1.58 or more, preferably 1.60 or more, more preferably 1.63 or more, it can be 1.65 or more, it can be 1.70 or more, and it can also be Can be above 1.75. According to the high refractive index organic material with higher refractive index, the target refractive index can be achieved even if a smaller amount of high refractive index organic material is used. This case is preferable from the viewpoint of suppressing deterioration in adhesive properties or optical properties. The upper limit of the refractive index of the high-refractive-index organic material is not particularly limited, but from the viewpoint of compatibility within the adhesive or the ease of achieving a high refractive index and appropriate flexibility of the adhesive, it is, for example, 3.000 or less. It can be below 2.500, below 2.000, below 1.950, below 1.900, or below 1.850. In addition, the high refractive index organic material can also be used as a plasticizer that functions as a plasticizer for imparting flexibility to the adhesive layer. Furthermore, the refractive index of the high refractive index organic material and adhesive layer was measured using an Abbe refractometer at a measuring wavelength of 589 nm and a measuring temperature of 25°C. When the manufacturer provides a nominal value of the refractive index at 25°C, this nominal value can be used.

The difference between the refractive index n _b of the high refractive index organic material and the refractive index n _a of the acrylic polymer, that is, n _{b −na} (hereinafter also referred to as “Δn _A ”), is set to a value greater than 0. Δn _A may be, for example, 0.02 or more, 0.05 or more, 0.07 or more, 0.10 or more, 0.15 or more, 0.20 or more, or 0.25 or more. By selecting the acrylic polymer and the high refractive index organic material so that Δn _A becomes larger, the refractive index raising effect obtained by using the high refractive index organic material tends to increase. Moreover, from the viewpoint of the compatibility of the high refractive index organic material in the adhesive layer, Δn _A may be, for example, 0.70 or less, 0.60 or less, 0.50 or less, 0.40 or less, or 0.35 or less.

The difference between the refractive index n _b of the high refractive index organic material and the refractive index n _T of the adhesive layer including the high refractive index organic material, that is, n _b −n _T (hereinafter also referred to as “Δn _B ”) can be set to be greater than value of 0. In certain aspects, Δn _B is, for example, above 0.02, above 0.05, above 0.07, above 0.10, above 0.15, above 0.20, or above 0.25. By selecting the composition of the adhesive layer and the high refractive index organic material so that Δn _B becomes larger, the refractive index raising effect obtained by using the high refractive index organic material tends to increase. In addition, based on the compatibility within the adhesive layer or the transparency of the adhesive layer, in some aspects, Δn _B may be, for example, 0.70 or less, 0.60 or less, 0.50 or less, or 0.40. below or below 0.35.

The molecular weight of the organic material used as the high refractive index organic material is not particularly limited and can be selected according to the purpose. From the viewpoint of achieving a well-balanced combination of the effect of increasing the refractive index and other properties (such as optical properties such as flexibility and haze suitable for adhesives), the molecular weight of the high refractive index organic material is preferably less than about 10,000. Preferably it is less than 5000, more preferably less than 3000 (for example, less than 1000), it may be less than 800, it may be less than 600, it may be less than 500, it may be less than 400. It can be advantageous from the viewpoint of improving the compatibility within the adhesive layer that the molecular weight of the high refractive index organic material is not too large. In addition, the molecular weight of the high refractive index organic material may be, for example, 130 or more, or may be 150 or more. From the viewpoint of increasing the refractive index of the high refractive index organic material, the molecular weight of the high refractive index organic material is preferably 170 or more, more preferably 200 or more, may be 230 or more, may be 250 or more, may be 270 or more , it can be more than 500, it can be more than 1,000, it can also be more than 2,000. A polymer with a molecular weight of about 1,000 to 10,000 (for example, 1,000 or more and less than 5,000) can be used as the high refractive index organic material. Regarding the molecular weight of the high refractive index organic material, the molecular weight calculated based on the chemical structure of a non-polymer or a polymer with a low degree of polymerization (for example, about 2 to 5 polymers) can be used, or the matrix-assisted laser desorption free flight time can be used. Measured values using mass spectrometry (MALDI-TOF-MS). When the high refractive index organic material is a polymer with a higher degree of polymerization, the weight average molecular weight (Mw) calculated based on GPC performed under appropriate conditions can be used. When the manufacturer provides a nominal value for molecular weight, the nominal value can be used.

Examples of organic materials that can be options for high refractive index organic materials include: organic compounds with aromatic rings, organic compounds with heterocyclic rings (which can be aromatic rings or non-aromatic heterocyclic rings), etc., but they are not Not limited to these.

The above-mentioned organic compound having an aromatic ring that can be used as a high refractive index organic material (hereinafter also referred to as an “aromatic ring-containing compound”) has an aromatic ring that can be derived from the aromatic ring of the above-mentioned compound that can be used as an aromatic ring-containing monomer. Select among those with the same aromatic ring.

The above-mentioned aromatic ring may have one, two or more substituents on the ring atoms, or may have no substituents. When there is a substituent, examples of the substituent include: alkyl group, alkoxy group, aryloxy group, hydroxyl group, halogen atom (fluorine atom, chlorine atom, bromine atom, etc.), hydroxyalkyl group, hydroxyalkoxy group group, glycidoxy group, etc., but are not limited to these. In the substituent containing carbon atoms, the number of carbon atoms contained in the substituent is, for example, 1 to 10, preferably 1 to 6, preferably 1 to 4, more preferably 1 to 3, for example, it can be 1 or 2. The above-mentioned aromatic ring may have no substituents on the ring atoms, or may have one or more substituents selected from the group consisting of an alkyl group, an alkoxy group, and a halogen atom (such as a bromine atom). ring.

Examples of aromatic ring-containing compounds that can be used as high refractive index organic materials include compounds that can be used as aromatic ring-containing monomers; and compounds that can be used as aromatic ring-containing monomers as monomers. Oligomers of units; from compounds that can be used as monomers containing aromatic rings, remove the group with an ethylenically unsaturated group (which can be a substituent bonded to a ring atom) or the ethylene component in the group Part of the sexually unsaturated group is substituted with a group that does not have a hydrogen atom or an ethylenically unsaturated group (such as hydroxyl, amine, halogen atom, alkyl, alkoxy, hydroxyalkyl, hydroxyalkoxy, glycidoxy base, etc.), but are not limited to these. Non-limiting examples of compounds containing aromatic rings that can be used as high refractive index organic materials include: benzyl acrylate, m-phenoxybenzyl acrylate, 2-(o-phenylphenoxy)ethyl acrylate , phenoxyethyl acrylate, phenoxydiethylene glycol acrylate, phenoxy polyethylene glycol acrylate, 2-hydroxy-3-phenoxypropyl acrylate, the above-mentioned monomers with fluorine structure, have Monomers with a dinaphthothiophene structure, monomers with a dibenzothiophene structure, and other monomers containing aromatic rings; 3-phenoxybenzyl alcohol, dinaphthothiophene and their derivatives (for example, in dinaphthothiophene rings Compounds having a structure with one or more substituents selected from hydroxyl, carbinyl, diethanol, glycidyl, etc.), which do not have ethylenically unsaturated groups. Compounds containing aromatic rings, etc. In addition, the aromatic ring-containing compound may be an oligomer containing such an aromatic ring-containing monomer as a monomer unit (preferably an oligomer with a molecular weight of about 5000 or less, more preferably about 1000 or less; for example, 2 ~A low polymer of about 5 polymers). The above-mentioned oligomer may be, for example: a homopolymer of a monomer containing an aromatic ring; a copolymer of one or more types of monomers containing an aromatic ring; a copolymer of one or more types of monomers containing an aromatic ring and Copolymers of other monomers, etc. As the above-mentioned other monomers, one or more monomers that do not have an aromatic ring can be used.

In some aspects, as the high refractive index organic material, in terms of easily obtaining a higher high refractive index effect, organic compounds having two or more aromatic rings in one molecule (hereinafter also referred to as "Compounds containing multiple aromatic rings"). The compound containing a plurality of aromatic rings may or may not have a polymerizable functional group such as an ethylenically unsaturated group. In addition, the compound containing a plurality of aromatic rings may be a polymer or a non-polymer. In addition, the above-mentioned polymer can be an oligomer containing a monomer containing a plurality of aromatic rings as a monomer unit (preferably an oligomer with a molecular weight of about 5000 or less, more preferably about 1000 or less; for example, 2 to 5 Low polymer (polymer). The above-mentioned oligomer may be, for example: a homopolymer of a monomer containing a plurality of aromatic rings; a copolymer of one or more types of monomers containing a plurality of aromatic rings; a copolymer of one or more types of monomers containing a plurality of aromatic rings. Copolymers of aromatic ring monomers and other monomers, etc. The above-mentioned other monomers may be monomers containing aromatic rings that are not monomers containing multiple aromatic rings, may be monomers without aromatic rings, or may be a combination thereof.

Non-limiting examples of compounds containing multiple aromatic rings include compounds having a structure in which two or more non-condensed aromatic rings are bonded via a linking group, compounds having two or more non-condensed aromatic rings directly (i.e., Compounds with structures that are chemically bonded without other atoms), compounds with condensed aromatic ring structures, compounds with fluorine structures, compounds with dinaphthothiophene structures, compounds with dibenzothiophene structures, etc. The compound containing a plurality of aromatic rings can be used individually by 1 type or in combination of 2 or more types.

Specific examples of the compound having a fluorine structure include the above-mentioned monomer having a fluorine structure, or an oligomer that is a homopolymer or copolymer of the monomer, and further examples include 9,9-bis( 4-Hydroxyphenyl) fluorine (refractive index: 1.68), 9,9-bis(4-aminophenyl) fluorine (refractive index: 1.73), 9,9-bis(4-hydroxy-3-methylbenzene) 9,9-bis[4-(2-hydroxyethoxy)phenyl]fluorine (refractive index: 1.65) and its derivatives.

Specific examples of the compound having a dinaphthothiophene structure include the monomer having a dinaphthothiophene structure, an oligomer that is a homopolymer or a copolymer of the monomer, and further examples. dinaphthothiophene (refractive index: 1.808); 6-hydroxymethyl dinaphthothiophene (refractive index: 1.766) and other hydroxyalkyl dinaphthothiophenes; 2,12-dihydroxydinaphthothiophene (refractive index: 1.750 ) and other dihydroxydinaphthothiophenes; 2,12-dihydroxyethoxydinaphthothiophene (refractive index: 1.677) and other dihydroxyalkoxydinaphthothiophenes; 2,12-diglycidoxydinaphthothiophenes Diglycidyloxy dinaphthothiophene (refractive index 1.723) and other diglycidyloxy dinaphthothiophenes; 2,12-diallyloxy dinaphthothiophene (abbreviation: 2,12-DAODNT, refractive index 1.729), etc. have more than 2 Ethylenically unsaturated dinaphthothiophene and other dinaphthothiophenes and their derivatives.

Specific examples of the compound having the dibenzothiophene structure include the monomer having the dibenzothiophene structure, an oligomer that is a homopolymer or a copolymer of the monomer, and further examples. Dibenzothiophene (refractive index: 1.607), 4-dimethyldibenzothiophene (refractive index: 1.617), 4,6-dimethyldibenzothiophene (refractive index: 1.617), etc.

Examples of organic compounds having a heterocyclic ring (hereinafter also referred to as organic compounds containing a heterocyclic ring) that can be used as high refractive index organic materials include thioepoxy compounds, compounds having a tricyclic ring, and the like. Examples of the thioepoxy compound include bis(2,3-epithiopropyl) disulfide and its polymer (refractive index: 1.74) described in Japanese Patent No. 3712653. Examples of the compound having a tri𠯤 ring include a compound having at least one (for example, 3 to 40, preferably 5 to 20) tri𠯤 ring in one molecule. Furthermore, since the three-𠯤 ring is aromatic, compounds with the three-𠯤 ring are also included in the above-mentioned concept of compounds containing aromatic rings. In addition, compounds with multiple tri-𠯤-rings are also included in the above-mentioned concept of compounds containing multiple aromatic rings. The concept of compounds.

As the high refractive index organic material, a compound having no ethylenically unsaturated group can be preferably used. This can suppress deterioration of the adhesive composition caused by heat or light (decrease in leveling properties due to progression of gelation or increase in viscosity) and improve storage stability. The use of a high refractive index organic material that does not have an ethylenically unsaturated group suppresses the formation of an adhesive film having an adhesive layer containing the high refractive index organic material or a laminate containing the adhesive film. It is also preferable from the viewpoint of dimensional changes or deformation (warpage, surface ripples, etc.) caused by reaction, generation of optical strain, etc.

In the aspect of using an oligomer as a high refractive index organic material, the oligomer can be obtained by polymerizing the corresponding monomer components using a known method. When the oligomer is produced by radical polymerization, a polymerization initiator, a chain transfer agent, an emulsifier, etc. for radical polymerization can be appropriately added to the monomer component to perform polymerization. The above-mentioned polymerization initiator, chain transfer agent, emulsifier, etc. used for radical polymerization are not particularly limited and can be appropriately selected and used. Furthermore, the weight average molecular weight of the oligomer can be controlled according to the usage amounts of the polymerization initiator and chain transfer agent and the reaction conditions, and the usage amounts can be appropriately adjusted based on their types.

Examples of the chain transfer agent include lauryl mercaptan, glycidyl mercaptan, thioglycolic acid, 2-mercaptoethanol, α-thioglycerol, thioglycolic acid, 2-ethylhexyl thioglycolate, 2,3-dimercapto-1-propanol, etc. One type of chain transfer agent may be used alone, or two or more types may be mixed and used. The amount of chain transfer agent used can be appropriately set according to the composition of the monomer components used in the synthesis of the oligomer or the type of chain transfer agent to obtain an oligomer with a desired weight average molecular weight. In some aspects, relative to 100 parts by weight of the total amount of monomers used in the synthesis of the oligomer, the amount of chain transfer agent used is suitably set to about 15 parts by weight or less, and it can be 10 parts by weight or less, or it can be 5 parts by weight. Parts by weight or less. There is no particular limit to the lower limit of the amount of chain transfer agent used relative to 100 parts by weight of the total amount of monomers used in the synthesis of the oligomer. For example, it can be 0.01 parts by weight or more, 0.1 parts by weight or more, or 0.5 parts by weight. parts or more, or more than 1 part by weight.

The usage amount of the high refractive index organic material relative to 100 parts by weight of the acrylic polymer (the total amount of equal amounts when using multiple compounds) is not particularly limited as long as it exceeds 0 parts by weight and can be adjusted according to the purpose. settings. The amount of the high-refractive index organic material used may be, for example, 80 parts by weight or less based on 100 parts by weight of the acrylic polymer, so as to achieve a well-balanced combination of high refractive index of the adhesive and suppression of deterioration in adhesive properties or optical properties. From this point of view, it is advantageous to set it to 60 parts by weight or less, and preferably to set it to 45 parts by weight or less. From the viewpoint of placing greater emphasis on adhesive properties or optical properties, the amount of the high refractive index organic material used may be, for example, 30 parts by weight or less, 20 parts by weight or less, or 15 parts by weight based on 100 parts by weight of the acrylic polymer. parts or less, and may also be 10 parts by weight or less. In addition, from the viewpoint of increasing the refractive index of the adhesive, the usage amount of the high refractive index organic material can be, for example, 1 part by weight or more, preferably 3 parts by weight, based on 100 parts by weight of the acrylic polymer. The above is preferably 5 parts by weight or more, may be 7 parts by weight or more, may be 10 parts by weight or more, may be 15 parts by weight or more, may be 20 parts by weight or more.

The adhesive layer of the present invention is not particularly limited, but preferably contains an ultraviolet absorber (UVA). If the adhesive layer of the present invention contains an ultraviolet absorber, the deterioration of the OLED element caused by ultraviolet light contained in external light can be suppressed, and an OLED display device with excellent weather resistance can be obtained even without using a polarizing plate. In addition, it is possible to suppress the deterioration of the high refractive index component caused by ultraviolet rays and maintain a high lighting rate. In addition, the ultraviolet absorber can be used individually or in combination of 2 or more types.

The above-mentioned ultraviolet absorber is not particularly limited, and examples thereof include benzotriazole-based ultraviolet absorbers, hydroxyphenyl trisulfonate-based ultraviolet absorbers, benzophenone-based ultraviolet absorbers, and salicylate-based ultraviolet absorbers. , cyanoacrylate ultraviolet absorbers, oxybenzophenone ultraviolet absorbers, etc.

Examples of benzotriazole-based ultraviolet absorbers (benzotriazole-based compounds) include: 2-(2-hydroxy-5-tert-butylphenyl)-2H-benzotriazole (trade name " TINUVIN PS", manufactured by BASF), phenylpropionic acid and 3-(2H-benzotriazol-2-yl)-5-(1,1-dimethylethyl)-4-hydroxy (C7-9 side chain and linear alkyl) ester compound (trade name "TINUVIN 384-2", manufactured by BASF), 3-[3-tert-butyl-4-hydroxy-5-(5-chloro-2H-benzo Triazol-2-yl)phenyl]octyl propionate and 3-[3-tert-butyl-4-hydroxy-5-(5-chloro-2H-benzotriazol-2-yl)phenyl]propanate A mixture of 2-ethylhexyl acid (trade name "TINUVIN 109", manufactured by BASF), 2-(2H-benzotriazol-2-yl)-4,6-bis(1-methyl-1- Phenylethyl)phenol (trade name "TINUVIN 900", manufactured by BASF), 2-(2H-benzotriazol-2-yl)-6-(1-methyl-1-phenylethyl)- 4-(1,1,3,3-Tetramethylbutyl)phenol (trade name "TINUVIN 928", manufactured by BASF), 3-(3-(2H-benzotriazol-2-yl)-5- Reaction product of tert-butyl-4-hydroxyphenyl)methyl propionate/polyethylene glycol 300 (trade name "TINUVIN 1130", manufactured by BASF), 2-(2H-benzotriazol-2-yl) ) p-cresol (trade name "TINUVIN P", manufactured by BASF), 2-(2H-benzotriazol-2-yl)-4,6-bis(1-methyl-1-phenylethyl) Phenol (trade name "TINUVIN 234", manufactured by BASF), 2-[5-chloro-2H-benzotriazol-2-yl]-4-methyl-6-(tert-butyl)phenol (trade name "TINUVIN 326", manufactured by BASF Corporation), 2-(2H-benzotriazol-2-yl)-4,6-di-tertiary amylphenol (trade name "TINUVIN 328", manufactured by BASF Corporation), 2- (2H-benzotriazol-2-yl)-4-(1,1,3,3-tetramethylbutyl)phenol (trade name "TINUVIN 329", manufactured by BASF), 2,2'- Methyl bis[6-(2H-benzotriazol-2-yl)-4-(1,1,3,3-tetramethylbutyl)phenol] (trade name "TINUVIN 360", manufactured by BASF) , the reaction product of methyl 3-(3-(2H-benzotriazol-2-yl)-5-tert-butyl-4-hydroxyphenyl)propionate and polyethylene glycol 300 (trade name "TINUVIN 213", manufactured by BASF Corporation), 2-(2H-benzotriazol-2-yl)-6-dodecyl-4-methylphenol (trade name "TINUVIN 571", manufactured by BASF Corporation), 2- [2-Hydroxy-3-(3,4,5,6-tetrahydrophthalimide-methyl)-5-methylphenyl]benzotriazole (trade name "Sumisorb 250", Sumitomo Chemical Co., Ltd.), 2,2'-methylenebis[6-(2H-benzotriazol-2-yl)-4-tertiary octylphenol] (trade name "Adekastab LA-31", ADEKA Co., Ltd.), etc.

Examples of the hydroxyphenyltrixamethonium-based ultraviolet absorber (hydroxyphenyltrixamethonium-based compound) include: 2-(4,6-bis(2,4-dimethylphenyl)-1,3,5 -Reaction product of tris-2-yl)-5-hydroxyphenyl and [(C10-C16 (mainly C12-C13) alkoxy)methyl] ethylene oxide (trade name "TINUVIN 400", BASF company), 2-[4,6-bis(2,4-dimethylphenyl)-1,3,5-tri-2-yl]-5-[3-(dodecyloxy) -2-Hydroxypropoxy]phenol), 2-(2,4-dihydroxyphenyl)-4,6-bis-(2,4-dimethylphenyl)-1,3,5-trihydroxyphenyl Reaction product with glycidic acid (2-ethylhexyl) ester (trade name "TINUVIN 405", manufactured by BASF), 2,4-bis(2-hydroxy-4-butoxyphenyl)-6-( 2,4-dibutoxyphenyl)-1,3,5-trifluoroethylene (trade name "TINUVIN 460", manufactured by BASF), 2-(4,6-diphenyl-1,3,5- Tris-2-yl)-5-[(hexyl)oxy]phenol (trade name "TINUVIN 1577", manufactured by BASF), 2-(4,6-diphenyl-1,3,5-tris- -2-yl)-5-[2-(2-ethylhexyloxy)ethoxy]phenol (trade name "Adekastab LA-46", manufactured by ADEKA Co., Ltd.), 2-(2-hydroxy- 4-[1-Octyloxycarbonylethoxy]phenyl)-4,6-bis(4-phenylphenyl)-1,3,5-trifluoroethylene (trade name "TINUVIN 479", manufactured by BASF )wait. In addition, a compound represented by the following formula (5) (trade name "TINUVIN 477", manufactured by BASF Corporation) can be exemplified. [Chemistry 5]

Examples of benzophenone-based ultraviolet absorbers (benzophenone-based compounds) and oxybenzophenone-based ultraviolet absorbers (oxybenzophenone-based compounds) include: 2,4-dihydroxy Benzophenone, 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-methoxybenzophenone-5-sulfonic acid (anhydride and trihydrate), 2-hydroxy-4 -Octyloxybenzophenone, 4-dodecyloxy-2-hydroxybenzophenone, 4-benzyloxy-2-hydroxybenzophenone, 2,2'-dihydroxy-4-methyl Oxybenzophenone (trade name "KEMISORB 111", manufactured by Chemipro Kasei Co., Ltd.), 2,2',4,4'-tetrahydroxybenzophenone (trade name "SEESORB 106", manufactured by Shipro Kasei Co., Ltd. ), 2,2'-dihydroxy-4,4'-dimethoxybenzophenone, etc.

Examples of the salicylate-based ultraviolet absorber (salicylate-based compound) include: 2-acryloxyphenylbenzoate, 2-acryloxy-3-methylbenzoatephenyl ester, 2-Acrylyloxy-4-methylbenzoic acid phenyl ester, 2-acrylyloxy-5-methylbenzoic acid phenyl ester, 2-acrylyloxy-3-methoxyphenylbenzoate, 2 -Phenyl hydroxybenzoate, 2-hydroxy-3-methylbenzoic acid phenyl ester, 2-hydroxy-4-methylbenzoic acid phenyl ester, 2-hydroxy-5-methylbenzoic acid phenyl ester, 2-hydroxy- 3-Methoxyphenyl benzoate, 3,5-di-tert-butyl-4-hydroxybenzoate-2,4-di-tert-butylphenyl ester (trade name "TINUVIN 120", manufactured by BASF), etc. .

Examples of the cyanoacrylate ultraviolet absorber (cyanoacrylate compound) include: 2-cyanoacrylic acid alkyl ester, 2-cyanoacrylic acid cycloalkyl ester, and 2-cyanoacrylic acid alkoxy Alkyl ester, alkenyl 2-cyanoacrylate, alkynyl 2-cyanoacrylate, etc.

The above-mentioned ultraviolet absorber is preferably selected from the aspects of high ultraviolet absorbability, excellent optical properties, easy availability of a highly transparent adhesive layer, and excellent light stability. At least one type of ultraviolet absorber selected from the group consisting of free benzotriazole-based ultraviolet absorbers, benzophenone-based ultraviolet absorbers, and hydroxyphenyltrizotriazole-based ultraviolet absorbers, more preferably benzotriazole-based ultraviolet absorbers Ultraviolet absorber, benzophenone-based ultraviolet absorber. Particularly preferred is a benzotriazole ultraviolet absorber in which a group having 6 or more carbon atoms and a phenyl group having a hydroxyl group as a substituent are bonded to the nitrogen atom constituting the benzotriazole ring. Furthermore, from the viewpoint of preventing deterioration in appearance due to precipitation of the ultraviolet absorber, it is preferable to use a liquid ultraviolet absorber or two or more types of ultraviolet absorbers.

In addition, in order to obtain higher ultraviolet absorbability, the ultraviolet absorber preferably has an absorbance A determined below of 0.5 or less. Absorbance A: The absorbance measured by irradiating a 0.08% toluene solution of the above ultraviolet absorber with light of a wavelength of 400 nm.

When the adhesive layer of the present invention contains an ultraviolet absorber, the content of the above-mentioned ultraviolet absorber in the adhesive layer of the present invention (especially the acrylic adhesive layer) is not particularly limited. Containing ultraviolet rays causes deterioration of OLED elements, and in order to obtain an OLED display device with excellent weather resistance even without using a polarizing plate, it is preferably 0.01 part by weight or more based on 100 parts by weight of the acrylic polymer, and more preferably It is 0.05 part by weight or more, and more preferably it is 0.1 part by weight or more. In addition, the upper limit of the content of the ultraviolet absorber is to suppress the yellowing phenomenon of the adhesive caused by the addition of the ultraviolet absorber and to obtain excellent optical properties, high transparency, and excellent appearance characteristics. It is preferably 20 parts by weight or less, more preferably 10 parts by weight or less, based on 100 parts by weight of the acrylic polymer.

The above-mentioned ultraviolet absorber can be replaced by a pigment compound whose maximum absorption wavelength of the absorption spectrum falls in the wavelength range of 380 to 430 nm, or it can be used in combination with the above-mentioned ultraviolet absorber to contain a pigment compound whose maximum absorption wavelength of the above-mentioned absorption spectrum falls within the wavelength range of 380 to 430 nm. Pigment compounds in the wavelength range. This pigment compound can also inhibit the deterioration of OLED elements or the deterioration of high refractive index components caused by ultraviolet light.

The above-mentioned pigment compounds may be used alone, or two or more types may be mixed and used. When only the above pigment compound is used, the content based on the entire pigment compound is preferably 0.1 to 20 parts by weight, preferably 0.1 to 10 parts by weight based on 100 parts by weight of the base polymer (for example, an acrylic polymer). parts, preferably 0.1 to 5 parts by weight, more preferably 0.5 to 3 parts by weight. By setting the added amount of the pigment compound within the above range, light in an area that does not affect the light emission of the OLED element can be fully absorbed, and by using the adhesive layer formed of the adhesive composition, the OLED element can be suppressed Deterioration or deterioration of high refractive index components, so it is better.

Either the above-mentioned ultraviolet absorber or the pigment compound may be used, but it is preferable to use the above-mentioned ultraviolet absorber and the pigment compound together. Although the ultraviolet absorber can absorb light with a wavelength of, for example, 380 nm, it does not fully absorb light in the wavelength range (380 nm to 430 nm) that is closer to the light-emitting area of the OLED element (the longer wavelength side than 430 nm). , there may be cases where deterioration occurs due to the transmitted light. The above-mentioned pigment compound can suppress the transmission of light at wavelengths closer to the shorter wavelength side (380 nm to 430 nm) than the light-emitting region of the OLED element (the long wavelength side longer than 430 nm) by using the above-mentioned ultraviolet absorber and pigment compound together. , can fully ensure the transmittance of visible light in the light-emitting area of the above-mentioned OLED element. In the present invention, by using such a pigment compound in combination with the above-mentioned ultraviolet absorber, it is possible to fully absorb light in a region (wavelength 380 nm to 430 nm) that does not affect the light emission of the OLED element, and to make the OLED The light-emitting area of the element (the long wavelength side longer than 430 nm) is fully transmitted. As a result, it is possible to simultaneously suppress the deterioration of the OLED element due to external light and the deterioration of high refractive index components. When the above-mentioned ultraviolet absorber and a pigment compound are used together, the above-mentioned ultraviolet absorber is preferably 0.1 to 10 parts by weight, and preferably 0.1 to 5 parts by weight based on 100 parts by weight of the base polymer (for example, an acrylic polymer). parts, more preferably 0.5 to 3 parts by weight. The pigment compound is preferably about 0.1 to 10 parts by weight, more preferably about 0.1 to 5 parts by weight, and even more preferably 0.5 to 3 parts by weight based on 100 parts by weight of the base polymer (for example, an acrylic polymer).

The pigment compound is not particularly limited as long as the maximum absorption wavelength of the absorption spectrum falls within the wavelength region of 380 to 430 nm. Furthermore, the maximum absorption wavelength refers to the absorption maximum wavelength that shows the maximum absorbance when there are multiple absorption maxima in the spectral absorption spectrum in the wavelength range of 300 to 460 nm.

The maximum absorption wavelength of the absorption spectrum of the pigment compound is preferably within the wavelength range of 380 to 420 nm. In addition, the dye compound is not particularly limited as long as it has the above-mentioned wavelength characteristics. Preferably, it is a material that does not have fluorescent or phosphorescent properties (photoluminescence) that does not hinder the display properties of the OLED element.

Examples of the organic dye compound include methine azo compounds, indole compounds, cinnamic acid compounds, pyrimidine compounds, porphyrin compounds, cyanine compounds, and the like.

As the above-mentioned organic dye compound, a commercially available one can be suitably used. Specifically, as the above-mentioned indole-based compound, BONASORB UA3911 (trade name, maximum absorption wavelength of absorption spectrum: 398 nm, Orient Chemical Industry Co., Ltd. ), examples of the cinnamic acid-based compound include SOM-5-0106 (trade name, maximum absorption wavelength of absorption spectrum: 416 nm, manufactured by Orient Chemical Industry Co., Ltd.), and examples of the porphyrin-based compound include FDB-001 (trade name, maximum absorption wavelength of absorption spectrum: 420 nm, manufactured by Yamada Chemical Industry Co., Ltd.). Examples of cyanine compounds include merocyanine compounds (trade name: FDB-009, maximum absorption wavelength of absorption spectrum: Maximum absorption wavelength: 394 nm, manufactured by Yamada Chemical Industry Co., Ltd.), polymethine compound (trade name: DAA-247, maximum absorption wavelength of absorption spectrum: 389 nm, manufactured by Yamada Chemical Industry Co., Ltd.), etc., among which , from the viewpoint of cross-linking inhibition and optical reliability, the above-mentioned cyanine compound is preferred, and a polymethine compound is particularly preferred.

The adhesive layer of the present invention may also contain a light stabilizer. When the adhesive layer of the present invention contains a light stabilizer, it is particularly preferred to contain both the above-mentioned ultraviolet absorber and the light stabilizer. Since light stabilizers can capture free radicals generated by photo-oxidation, they can improve the resistance of the adhesive layer to light (especially ultraviolet light). In addition, a light stabilizer can be used individually or in combination of 2 or more types.

The above-mentioned light stabilizer is not particularly limited, and examples thereof include: phenol-based light stabilizers (phenol-based compounds), phosphorus-based light stabilizers (phosphorus-based compounds), thioether-based light stabilizers (thioether-based compounds), amines It is a light stabilizer (amine compound) (especially a hindered amine stabilizer (hindered amine compound)), etc.

Examples of the phenolic light stabilizer (phenol compound) include 2,6-di-tert-butyl-4-methylphenol and 4-hydroxymethyl-2,6-di-tert-butylphenol. , 2,6-di-tert-butyl-4-ethylphenol, butylated hydroxyanisole, 3-(4-hydroxy-3,5-di-tert-butylphenyl) n-octadecane propionate ester, (4-hydroxy-3-methyl-5-tert-butyl)benzylmalonate distearyl, tocopherol, 2,2'-methylenebis(4-methyl-6- tert-butylphenol), 2,2'-methylenebis(4-ethyl-6-tert-butylphenol), 4,4'-methylenebis(2,6-di-tert-butylphenol) Phenol), 4,4'-butylene bis(6-tert-butyl m-cresol), 4,4'-thiobis(6-tert-butyl m-cresol), styrenated phenol, N, N'-hexamethylene bis(3,5-di-tert-butyl-4-hydroxyphenylpropenamide, bis(3,5-di-tert-butyl-4-hydroxybenzylphosphonate ethyl ester) calcium , 1,1,3-tris(2-methyl-4-hydroxy-5-tert-butylphenyl)butane, 1,3,5-trimethyl-2,4,6-tris(3, 5-Di-tert-butyl-4-hydroxybenzyl)benzene, tetrakis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propyloxymethyl]methane, 1,6- Hexanediol-bis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate], 2,2'-methylenebis(4-methyl-6-cyclohexylphenol) ), 2,2'-methylenebis[6-(1-methylcyclohexyl)p-cresol], 1,3,5-tris(4-tert-butyl-3-hydroxyisocyanuric acid) -2,6-dimethylbenzyl) ester, 1,3,5-tris(3,5-di-tert-butyl-4-hydroxybenzyl)isocyanurate, triethylene glycol-bis [3-(3-tert-butyl-4-hydroxy-5-methylphenyl)propionate], 2,2'-oxalamide bis[ethyl 3-(3,5-di-tert-butyl hydroxy-4-hydroxyphenyl)propionate], 6-(4-hydroxy-3,5-di-tert-butylanilino)-2,4-dioctylthio-1,3,5-trisulfanyl , Bis[2-tert-butyl-4-methyl-6-(2-hydroxy-3-tert-butyl-5-methylbenzyl)phenyl] terephthalate, 3,9-bis {2-[3-(3-tert-butyl-4-hydroxy-5-methylphenyl)propionyloxy]-1,1-dimethylethyl}-2,4,8,10- Tetraxaspiro[5.5]undecane, 3,9-bis{2-[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionyloxy]-1,1-di Methylethyl}-2,4,8,10-tetraoxasspiro[5.5]undecane, etc.

Examples of the phosphorus-based light stabilizer (phosphorus-based compound) include: tris(nonylphenyl)phosphite, tris(2,4-di-tert-butylphenyl)phosphite, and tris(nonylphenyl)phosphite. 2-tert-butyl-4-(3-tert-butyl-4-hydroxy-5-methylphenylthio)-5-methylphenyl] ester, tripecyl phosphite, octyl phosphite Phenyl ester, di(decyl)phosphite monophenyl ester, di(tridecyl)pentaerythritol diphosphite, distearyl pentaerythritol diphosphite, di(nonylphenyl)pentaerythritol diphosphite , bis(2,4-di-tert-butylphenyl)pentaerythritol diphosphite, bis(2,6-di-tert-butyl-4-methylphenyl)pentaerythritol diphosphite, bis(2, 4,6-tri-tert-butylphenyl)pentaerythritol diphosphite, tetrakis(tridecyl)isopropylidenediphenol diphosphite, tetrakis(tridecyl)-4,4'-n- Butylene bis(2-tert-butyl-5-methylphenol) diphosphite, hexa(tridecyl)-1,1,3-tris(2-methyl-4-hydroxy-5-th Tributylphenyl)butane triphosphite, tetrakis (2,4-di-tert-butylphenyl) diphenylene diphosphonite, 9,10-dihydro-9-oxa-10-phosphorus Zaphenanthrene-10-oxide, tris(2-[(2,4,8,10-tetratert-butyldibenzo[d,f][1,3,2]dioxaphosphene -6-yl)oxy]ethyl)amine, etc.

Examples of thioether-based light stabilizers (thioether-based compounds) include dilauryl thiodipropionate, dimyristyl thiodipropionate, and distearyl thiodipropionate. Thiol dipropionate compounds; β-alkyl mercaptopropionate compounds of polyhydric alcohols such as tetrakis [methylene (3-dodecylthio) propionate] methane, etc.

Examples of the amine light stabilizer (amine compound) include a polymer of dimethyl succinate and 4-hydroxy-2,2,6,6-tetramethyl-1-piperidineethanol (trade name "TINUVIN 622", manufactured by BASF), a polymer of dimethyl succinate and 4-hydroxy-2,2,6,6-tetramethyl-1-piperidineethanol, and N,N',N'', N'''-tetrakis(4,6-bis-(butyl-(N-methyl-2,2,6,6-tetramethylpiperidin-4-yl)amino)-tri𠯤-2- 1:1 reaction product of methyl)-4,7-diazadecane-1,10-diamine (trade name "TINUVIN 119", manufactured by BASF), dibutylamine・1,3-trisamine・N,N'-bis(2,2,6,6-tetramethyl-4-piperidyl-1,6-hexamethylenediamine and N-(2,2,6,6-tetramethyl Condensation polymer of methyl-4-piperidinyl)butylamine (trade name "TINUVIN 2020", manufactured by BASF), poly[{6-(1,1,3,3-tetramethylbutyl)amino-1 ,3,5-Tris-2-4-diyl}{2,2,6,6-tetramethyl-4-piperidinyl}imino]hexamethylene{(2,2,6, 6-Tetramethyl-4-piperidyl)imino} (trade name "TINUVIN 944", manufactured by BASF), bis(1,2,2,6,6-pentamethyl-4-sebacic acid) A mixture of piperidinyl) ester and 1,2,2,6,6-pentamethyl-4-piperidinyl sebacate methyl ester (trade name "TINUVIN 765", manufactured by BASF), sebacate bis( 2,2,6,6-tetramethyl-4-piperidyl) ester (trade name "TINUVIN 770", manufactured by BASF), bis(2,2,6,6-tetramethyl-1 sebacate -(Octyloxy)-4-piperidinyl) ester, reaction product of 1,1-dimethylethyl hydroperoxide and octane (trade name "TINUVIN 123", manufactured by BASF), malonic acid Bis(1,2,2,6,6-pentamethyl-4-piperidyl)[[3,5-bis(1,1-dimethylethyl)-4-hydroxyphenyl]methyl] Butyl ester (trade name "TINUVIN 144", manufactured by BASF), cyclohexane and n-butyl peroxide 2,2,6,6-tetramethyl-4-piperidinamine-2,4,6-trichloro -The reaction product of the reaction product of 1,3,5-trifluoroethylene and 2-aminoethanol (trade name "TINUVIN 152", manufactured by BASF), bis(1,2,2,6,6-pentanoic acid) A mixture of methyl-4-piperidinyl) ester and methyl sebacate 1,2,2,6,6-pentamethyl-4-piperidinyl ester (trade name "TINUVIN 292", manufactured by BASF), 1,2,3,4-butanetetracarboxylic acid and 1,2,2,6,6-pentamethyl-4-piperidinol and 3,9-bis(2-hydroxy-1,1-dimethyl Ethyl)-2,4,8,10-tetraoxaspiro[5.5]undecane mixed ester (trade name "Adekastab LA-63P", manufactured by ADEKA Co., Ltd.), etc. As the amine stabilizer, a hindered amine stabilizer is particularly preferred.

When the adhesive layer of the present invention contains a light stabilizer, the content of the light stabilizer in the adhesive layer of the present invention (especially the acrylic adhesive layer) is not particularly limited, and it is easy to express resistance to light. In this regard, the amount is preferably 0.1 parts by weight or more, and more preferably 0.2 parts by weight or more based on 100 parts by weight of the acrylic polymer. In addition, the upper limit of the above content is preferably 5 parts by weight relative to 100 parts by weight of the acrylic polymer in terms of making it less likely to cause coloring of the light stabilizer itself and easily obtaining high transparency and optical properties. or less, more preferably 3 parts by weight or less.

The formation of the adhesive layer of the present invention is not particularly limited, and a cross-linking agent can also be used. For example, the acrylic polymer in the acrylic adhesive layer can be cross-linked to control the gel fraction. In addition, a cross-linking agent can be used individually or in combination of 2 or more types.

The above-mentioned cross-linking agent is not particularly limited, and examples thereof include isocyanate-based cross-linking agents, epoxy-based cross-linking agents, melamine-based cross-linking agents, peroxide-based cross-linking agents, urea-based cross-linking agents, and metal alkoxides. Physical cross-linking agent, metal chelate cross-linking agent, metal salt cross-linking agent, carbodiimide cross-linking agent, oxazoline cross-linking agent, aziridine cross-linking agent, amine cross-linking agent Cross-linking agents, etc. Among them, isocyanate cross-linking agents and epoxy cross-linking agents are preferred, and isocyanate cross-linking agents are more preferred.

Examples of the isocyanate cross-linking agent (polyfunctional isocyanate compound) include 1,2-ethylidene diisocyanate, 1,4-butylene diisocyanate, and 1,6-hexamethylene diisocyanate. Low-grade aliphatic polyisocyanates such as isocyanate; alicyclic polyisocyanates such as cyclopentyl diisocyanate, cyclohexyl diisocyanate, isophorone diisocyanate, hydrogenated toluene diisocyanate, hydrogenated xylene diisocyanate; 2,4 -Aromatic polyisocyanates such as toluene diisocyanate, 2,6-toluene diisocyanate, 4,4'-diphenylmethane diisocyanate, xylylene diisocyanate, etc. Examples of the isocyanate cross-linking agent include trimethylolpropane/toluene diisocyanate adduct (trade name "Coronate L", manufactured by Tosoh Co., Ltd.), trimethylolpropane/corona Methyl diisocyanate adduct (trade name "Coronate HL", manufactured by Tosoh Co., Ltd.), trimethylolpropane/xylylenediisocyanate adduct (trade name "Takenate D-110N", manufactured by Mitsui Chemicals ( stock) manufacturing) and other commercially available products.

Examples of the epoxy cross-linking agent (polyfunctional epoxy compound) include: N,N,N',N'-tetraglycidyl metaxylylenediamine, diglycidyl aniline, 1,3 -Bis(N,N-diglycidylaminomethyl)cyclohexane, 1,6-hexanediol diglycidyl ether, neopentyl glycol diglycidyl ether, ethylene glycol diglycidyl ether, propylene glycol Diglycidyl ether, polyethylene glycol diglycidyl ether, polypropylene glycol diglycidyl ether, sorbitol polyglycidyl ether, glycerol polyglycidyl ether, pentaerythritol polyglycidyl ether, polyglycerol polyglycidyl ether, sorbose Alcohol anhydride polyglycidyl ether, trimethylolpropane polyglycidyl ether, diglycidyl adipate, diglycidyl phthalate, triglycidyl-tris(2-hydroxyethyl)isocyanurate acid ester, resorcinol diglycidyl ether, bisphenol S-diglycidyl ether, and epoxy resins having two or more epoxy groups in the molecule. Examples of the epoxy-based cross-linking agent include commercially available products with the trade name "Tetrad C" (manufactured by Mitsubishi Gas Chemical Co., Ltd.).

When a cross-linking agent is used in forming the adhesive layer of the present invention, the usage amount of the above-mentioned cross-linking agent is not particularly limited. In order to obtain sufficient adhesion reliability, it is 100 parts by weight relative to the base polymer. , preferably 0.001 parts by weight or more, more preferably 0.01 parts by weight or more. In addition, regarding the upper limit of the above-mentioned usage amount, in order to obtain appropriate softness of the adhesive layer and improve the adhesive force, it is preferably 10 parts by weight or less and more preferably 5 parts by weight based on 100 parts by weight of the base polymer. the following.

The adhesive layer (especially the acrylic adhesive layer) of the present invention may also contain a silane coupling agent in order to improve the bonding reliability under humidified conditions, especially to improve the bonding reliability to glass. In addition, a silane coupling agent can be used individually or in combination of 2 or more types. If the above-mentioned adhesive layer contains a silane coupling agent, the adhesion under humidified conditions, especially the adhesion to glass, can be improved.

The above-mentioned silane coupling agent is not particularly limited, and examples thereof include: γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropyltriethoxysilane, and γ-aminopropyltrimethoxysilane. Silane, N-phenyl-aminopropyltrimethoxysilane, etc. Furthermore, examples of the silane coupling agent include commercially available products with the trade name "KBM-403" (manufactured by Shin-Etsu Chemical Industry Co., Ltd.). Among these, γ-glycidoxypropyltrimethoxysilane is preferred as the silane coupling agent.

When the adhesive layer of the present invention contains a silane coupling agent, the content of the above-mentioned silane coupling agent in the adhesive layer of the present invention (especially the acrylic adhesive layer) is not particularly limited. It is based on 100 weight of the above-mentioned base polymer. parts, preferably 0.01 parts by weight or more, more preferably 0.02 parts by weight or more. Moreover, the upper limit of the content of the silane coupling agent is preferably 10 parts by weight or less, and more preferably 1 part by weight or less based on 100 parts by weight of the base polymer.

The adhesive layer of the present invention may optionally further contain cross-linking accelerators, adhesion-imparting resins (rosin derivatives, polyterpene resins, petroleum resins, oil-soluble phenols, etc.) and anti-aging agents within the scope that does not impair the effects of the present invention. , fillers, colorants (pigments or dyes, etc.), antioxidants, chain transfer agents, plasticizers, softeners, surfactants, antistatic agents and other additives. In addition, such additives can be used alone or in combination of two or more types.

The manufacturing method of the adhesive layer (especially the acrylic adhesive layer) of the present invention is not particularly limited. For example, the above-mentioned adhesive composition is coated (coated) on a base material (including the following resin layer, glass layer) or release liner, and allow the obtained adhesive composition layer to dry and harden; or apply (coat) the above-mentioned adhesive composition on the base material (including the following resin layer, glass layer) or release liner The adhesive composition layer obtained is irradiated with active energy rays to harden it. In addition, heating and drying may be further performed if necessary.

Examples of the active energy rays include ionizing radiation such as α rays, β rays, γ rays, neutron rays, and electron beams, or ultraviolet rays. Ultraviolet rays are particularly preferred. In addition, the irradiation energy, irradiation time, irradiation method, etc. of active energy rays are not particularly limited.

The above-mentioned adhesive composition can be produced using known or customary methods. For example, a solvent-based acrylic adhesive composition can be prepared by optionally mixing an additive (eg, ultraviolet absorber, etc.) into a solution containing the acrylic polymer. For example, an active energy ray-curable acrylic adhesive composition can be produced by optionally mixing additives (such as ultraviolet absorbers, etc.) into the mixture of acrylic monomers or partial polymers thereof.

In addition, a known coating method can also be used for coating (coating) of the said adhesive composition. For example, gravure roll coaters, reverse roll coaters, contact roll coaters, dip roll coaters, rod coaters, blade coaters, spray coaters, and notch wheel coaters can be used. , direct coater and other coating machines.

Especially when the adhesive layer is formed from an active energy ray curable adhesive composition, the active energy ray curable adhesive composition preferably contains a photopolymerization initiator. Furthermore, when the active energy ray-curable adhesive composition contains an ultraviolet absorber, it is preferred to include at least a photopolymerization initiator having light-absorbing properties in a broad wavelength range as the photopolymerization initiator. It is preferable to include at least a photopolymerization initiator that has light-absorbing properties for visible light in addition to ultraviolet light. The reason is that when there is concern that active energy ray curing will be inhibited by the action of ultraviolet absorbers, if a photopolymerization initiator with light-absorbing properties in a wide wavelength range is included, the adhesive composition will easily obtain higher photocurability.

(adhesive layer) The adhesive layer is a layer that can bond substances by being interposed between adherends, and when the adherends bonded by the adhesive layer are peeled off, the adhesive layer does not have practical adhesive force.

As the adhesive that forms the adhesive layer constituting the optical element of the present invention (hereinafter sometimes referred to as the "adhesive layer of the present invention"), various adhesives can be applied, and examples thereof include isocyanate-based adhesives and polyvinyl alcohol-based adhesives. Adhesives, gelatin-based adhesives, vinyl-based latex-based adhesives, water-based polyester, etc. These adhesives are usually used in the form of adhesives containing aqueous solutions (water-based adhesives) and contain 0.5 to 60% by weight of solid content. Among these, a polyvinyl alcohol-based adhesive is preferred, and a polyvinyl alcohol-based adhesive containing an acetoacetyl group is more preferred.

The above-mentioned water-based adhesive agent may contain a cross-linking agent. As the above-mentioned cross-linking agent, compounds having at least two functional groups in one molecule that are reactive with components such as polymers constituting the adhesive are generally used. Examples thereof include alkylene diamines; isocyanates; and cyclic compounds. Oxygen; aldehydes; amino-formaldehyde such as hydroxymethylurea, hydroxymethylmelamine, etc. The compounding amount of the crosslinking agent in the adhesive agent is usually about 10 to 60 parts by weight relative to 100 parts by weight of components such as polymers constituting the adhesive agent.

Examples of the adhesive include, in addition to the above, active energy ray-curing adhesives such as ultraviolet curing adhesives and electron beam curing adhesives. Examples of the active energy ray-curable adhesive include (meth)acrylate adhesives. Examples of the curing component in the (meth)acrylate adhesive agent include compounds having a (meth)acryl group and compounds having a vinyl group. Examples of the compound having a (meth)acrylyl group include chain alkyl (meth)acrylate having 1 to 20 carbon atoms, alicyclic alkyl (meth)acrylate, and (meth)acrylic acid. Alkyl (meth)acrylate such as polycyclic alkyl ester; (meth)acrylate containing hydroxyl group; (meth)acrylate containing epoxy group such as glycidyl (meth)acrylate, etc. The (meth)acrylate adhesive may also contain hydroxyethyl(meth)acrylamide, N-hydroxymethyl(meth)acrylamide, or N-methoxymethyl(meth)acrylamide , N-ethoxymethyl (meth) acrylamide, (meth) acrylamide, (meth) acryl morpholine and other nitrogen-containing monomers. The (meth)acrylate adhesive may also include tripropylene glycol diacrylate, 1,9-nonanediol diacrylate, tricyclodecane dimethanol diacrylate, and cyclic trimethylolpropane formal acrylate. , diethylene glycol diacrylate, EO modified diglyceryl tetraacrylate and other multi-functional monomers are used as cross-linking components. In addition, as the cationic polymerization curable adhesive agent, a compound having an epoxy group or an oxetanyl group can also be used. The compound having an epoxy group is not particularly limited as long as it has at least two epoxy groups in the molecule, and various generally known curable epoxy compounds can be used.

The above-mentioned adhesive may also contain appropriate additives if necessary. Examples of the additives include coupling agents such as silane coupling agents and titanium coupling agents, adhesion accelerators such as ethylene oxide, ultraviolet absorbers, deterioration inhibitors, dyes, processing aids, ion scavengers, and antioxidants. Adhesion imparting agent, filler, plasticizer, leveling agent, foaming inhibitor, antistatic agent, heat-resistant stabilizer, hydrolysis-resistant stabilizer, etc.

The above-mentioned adhesive can be applied to either one of the two adherends to be bonded, or to both. After lamination, a drying step can be performed to form the adhesive layer of the present invention including a coated dry layer. The above drying step may be followed by ultraviolet or electron beam irradiation if necessary. The thickness of the adhesive layer of the present invention is not particularly limited. When using a water-based adhesive, etc., it is preferably about 30 to 5000 nm, more preferably about 100 to 1000 nm. When using ultraviolet curable adhesive, electronic In the case of a beam hardening adhesive, etc., it is preferably about 0.1 to 100 μm, more preferably about 0.5 to 10 μm.

When the pressing elastic modulus of the adhesive layer of the present invention is Ea, the pressing elastic modulus Ea is preferably 1 GPa or more, more preferably 2 GPa or more, and still more preferably 3 GPa or more. If the above-mentioned press-fit elastic modulus Ea is 1 GPa or more, the impact resistance will be further improved. The press-fit elastic modulus Ea is, for example, 50 GPa or less, 30 GPa or less, or 10 GPa or less.

The above-mentioned indentation elastic modulus Ea can be measured based on the nanoindentation method. The above-mentioned nanoindentation method was measured under the conditions of a spherical indenter (radius of curvature 10 μm), a temperature of 25°C, and an indentation depth of 100 nm.

(resin layer) The resin layer constituting the optical element of the present invention (hereinafter sometimes referred to as the "resin layer of the present invention") is not particularly limited, and an example thereof is a plastic film. Examples of materials for the above plastic films include polyester resins such as polyethylene terephthalate (PET) and polyethylene naphthalate (PEN), and cyclic olefin polymers (COP). (For example, the trade name "ARTON" (manufactured by JSR Co., Ltd.), the trade name "Zeonor" (manufactured by Japan ZEON Co., Ltd.), etc.), acrylic resins such as polymethyl methacrylate (PMMA), polycarbonate (PC) ), triacetylcellulose (TAC), polypropylene, polyarylate, polyetheretherketone (PEEK), polyimide (PI), transparent polyimide (CPI), polyvinyl chloride, polyvinyl acetate ester, polyethylene, polypropylene, ethylene-propylene copolymer and other plastic materials, preferably polyethylene terephthalate (PET) and polyethylene naphthalate (PEN) with excellent dimensional stability and resistance to shrinkage Such as polyester resin, cyclic olefin polymer (COP), polycarbonate (PC), polyether ether ketone (PEEK), transparent polyimide (CPI), preferably polyethylene terephthalate ester (PET), transparent polyimide (CPI), especially transparent polyimide (CPI) with excellent impact resistance. Furthermore, these plastic materials can be used alone or in combination of two or more. The release liner that is peeled off when using the optical element of the present invention (when attaching) is not included in the "resin layer".

The resin layer of the present invention is preferably transparent. The total light transmittance (according to JIS K 7361-1) of the resin layer of the present invention in the visible light wavelength region is not particularly limited, but is preferably 85% or more, and more preferably 88% or more. In addition, the haze (based on JIS K 7136) of the resin layer of the present invention is not particularly limited, but is preferably 1.5% or less, more preferably 1.0% or less.

In the present invention, the difference in refractive index between the adhesive (the adhesive layer excluding light-scattering microparticles in the adhesive layer) and the resin layer (the absolute value of "refractive index of the adhesive" - "refractive index of the resin layer") has no Particularly limited, from the viewpoint of improving the interface anti-reflection property and improving the lighting rate of light from the OLED element, it is preferably 2 or less, more preferably 1 or less, further preferably 0.5 or less, and particularly preferably 0.3 or less.

The thickness of the resin layer of the present invention is not particularly limited, but is preferably 10 to 80 μm, for example. Furthermore, the resin layer of the present invention may have any form of single layer or multiple layers. In addition, the surface of the resin layer of the present invention can be appropriately subjected to known and conventional surface treatments such as corona discharge treatment, physical treatment such as plasma treatment, and chemical treatment such as primer treatment.

The resin layer of the present invention is not particularly limited, but preferably contains an ultraviolet absorber (UVA) or a pigment compound whose maximum absorption wavelength of the absorption spectrum falls in the wavelength region of 380 to 430 nm. If the resin layer of the present invention contains an ultraviolet absorber or the above-mentioned pigment compound, it can suppress the deterioration of the OLED element caused by ultraviolet rays contained in external light, and obtain an OLED display device with excellent weather resistance even without using a polarizing plate. In addition, it can suppress the deterioration of the high refractive index component of the adhesive layer caused by ultraviolet rays and maintain a high lighting rate. In particular, by containing the ultraviolet absorber or the above-mentioned pigment compound, the resin layer of the present invention can reduce the content of the ultraviolet absorber or the above-mentioned pigment compound in the adhesive layer of the present invention, and can inhibit the ultraviolet absorber in the adhesive layer of the present invention. Or the precipitation or exudation of the above-mentioned pigment compounds, so it is preferable.

As the ultraviolet absorber (UVA) or the above-mentioned pigment compound contained in the resin layer of the present invention, the same ultraviolet absorber (UVA) or the above-mentioned pigment compound contained in the adhesive layer of the present invention can be used. In addition, the ultraviolet absorber or the above-mentioned pigment compound can be used alone or in combination of two or more types.

When the resin layer of the present invention contains an ultraviolet absorber or the above-mentioned pigment compound, the respective content of the above-mentioned ultraviolet absorber or the above-mentioned pigment compound in the resin layer of the present invention is not particularly limited. Deterioration of OLED elements caused by ultraviolet rays, in order to obtain an OLED display device with excellent weather resistance even without using a polarizing plate, preferably 0.01 part by weight or more, more preferably 0.05 part by weight or more based on 100 parts by weight of the resin layer , and more preferably 0.1 parts by weight or more. In addition, the upper limit of the content of the above-mentioned ultraviolet absorber or the above-mentioned pigment compound is to suppress the yellowing phenomenon of the adhesive caused by adding the ultraviolet absorber and to obtain excellent optical properties, high transparency, and excellent appearance characteristics. In terms of aspect, it is preferably 10 parts by weight or less, more preferably 9 parts by weight or less, and still more preferably 8 parts by weight or less based on 100 parts by weight of the resin layer.

When both the resin layer and the adhesive layer of the present invention contain an ultraviolet absorber or the above-mentioned pigment compound, they may be adjusted so that the total amount falls within the above range.

The moisture permeability of the resin layer of the present invention is not particularly limited. For example, from the viewpoint of suppressing the separation and precipitation of additives such as high refractive index organic materials in the adhesive layer, it is preferable that the moisture permeability reaches a certain level (high transparency). Humidity), more preferably 40 g/m ² · 24 hours or more, further preferably 100 g/m ² · 24 hours or more, especially 200 g/m ² · 24 hours or more. The upper limit of the moisture permeability of the resin layer of the present invention is not particularly limited. From the perspective of suppressing humidification expansion, it may be 1200 g/m ² ·24 hours or less. By making the resin layer of the present invention have a higher moisture permeability, the lighting reliability tends to be improved. The moisture permeability of the resin layer of the present invention can be measured in accordance with JIS Z0208 at a temperature of 40°C and a relative humidity of 92%, and can be adjusted according to the type, thickness, etc. of the resin constituting the resin layer of the present invention.

(Glass layer) The glass layer constituting the optical element of the present invention (hereinafter sometimes referred to as the "glass layer of the present invention") is not particularly limited, and an appropriate one can be selected depending on the purpose. The glass layer of the present invention is classified based on composition, and examples thereof include soda-lime glass, borate glass, aluminosilicate glass, and quartz glass. In addition, according to the classification based on the alkali component, alkali-free glass and low-alkali glass can be exemplified. The content of the alkali metal component (such as Na ₂ O, K ₂ O, Li ₂ O) in the glass is preferably 15% by weight or less, more preferably 10% by weight or less.

Considering the surface hardness, air tightness or corrosion resistance of glass, the thickness of the glass layer of the present invention is preferably 20 μm or more. In addition, the glass layer of the present invention is ideally flexible and bendable like a film, and is capable of projecting a clear image by suppressing image ghosting. For this reason, the thickness is preferably 60 μm or less. The thickness of the glass layer of the present invention is further preferably from 30 μm to 55 μm, particularly preferably from 40 μm to 50 μm.

The light transmittance of the glass layer of the present invention at a wavelength of 550 nm is preferably more than 85%. The refractive index of the glass layer of the present invention at a wavelength of 550 nm is preferably 1.4 to 1.65. The density of the glass layer of the present invention is preferably 2.3 g/cm ³ to 3.0 g/cm ³ , and further preferably 2.3 g/cm ³ to 2.7 g/cm ³ .

The method of forming the glass layer of the present invention is not particularly limited, and an appropriate method can be used depending on the purpose. Typically, the glass layer of the present invention can be made by melting a mixture containing a main raw material such as silicon oxide or aluminum oxide, a defoaming agent such as Glauber's salt or antimony oxide, and a reducing agent such as carbon at a temperature of about 1400°C to 1600°C. , formed into a thin plate and then cooled. Examples of the method for forming the glass layer of the present invention include orifice downdraft method, melting method, and float method. In order to achieve thinning or improve smoothness, the glass layer formed into a plate shape by these methods may also be chemically polished using solvents such as hydrofluoric acid if necessary.

(hard coat) The hard coat layer constituting the optical element of the present invention (hereinafter sometimes referred to as the "hard coat layer of the present invention") can be made of any appropriate resin as long as it has sufficient surface hardness, excellent mechanical strength, and excellent light transmittance. form. Specific examples of the resin include thermosetting resin, thermoplastic resin, ultraviolet curing resin, electron beam curing resin, and two-liquid mixed resin. Ultraviolet curable resin is preferred. The reason is that the hard coat layer can be formed with simple operation and high efficiency.

Specific examples of ultraviolet curable resins include polyester-based, acrylic-based, urethane-based, amide-based, silicone-based, and epoxy-based ultraviolet curable resins. UV-curable resins include UV-curable monomers, oligomers, and polymers. As a preferred ultraviolet curable resin, a resin composition containing an acrylic monomer component or an oligomer component having preferably two or more, more preferably three to six ultraviolet polymerizable functional groups can be exemplified. Typically, a photopolymerization initiator is blended with an ultraviolet curable resin.

The hard coat layer of the present invention can be formed by any appropriate method. For example, the hard coat layer of the present invention can be formed by applying a resin composition for forming a hard coat layer on a base material (including the above-mentioned resin layer and glass layer), drying it, and irradiating the dried coating film with ultraviolet rays to harden it. .

The thickness of the hard coating layer of the present invention is, for example, 2 to 20 μm, preferably 4 to 15 μm, and more preferably 4 to 10 μm.

From the viewpoint of antifouling properties, the water contact angle of the hard coat layer of the present invention is preferably 95° or more, more preferably 100° or more, and further preferably 105° or more. The water contact angle of the hard coat layer of the present invention is measured according to JIS R3257, and can be adjusted according to the type of resin constituting the hard coat layer, hardening conditions, etc. Furthermore, the hard coating layer of the present invention preferably has a water contact angle within the above range after the following steel wool test. ＜Steel wool test＞ Cut steel wool "Product No. #0000" manufactured by TRUSCO into 1 cm squares, and rub the surface of the hard coating back and forth 1,000 times under the conditions of a load of 1 kg and a moving speed of 100 mm/second.

From the viewpoint of excellent surface hardness and scratch resistance, the Vickers hardness of the hard coat layer of the present invention is preferably 80 or more, more preferably 90 or more, and still more preferably 100 or more. The Vickers hardness of the hard coating layer of the present invention is measured according to JIS Z2244, and can be adjusted according to the type of resin constituting the hard coating layer, hardening conditions, etc.

From the viewpoint of antifouling properties, the surface element ratio of the carbon element on the surface of the hard coat layer of the present invention is 50 atomic % or less, preferably 45 atomic % or less, and the fluorine element ratio on the surface of the hard coat layer is 30 atomic %. %above. In addition, the nitrogen element ratio on the surface of the hard coat layer is, for example, less than 1.5 atomic %, preferably 1.3 atomic % or less, for example, 0 atomic % or more. The surface element ratio of fluorine element, carbon element, and nitrogen element on the surface of the hard coat layer of the present invention can be measured by X-ray photoelectron spectroscopy, and can be adjusted according to the type of resin constituting the hard coat layer, hardening conditions, etc.

(Anti-reflective layer) The antireflection layer constituting the optical element of the present invention (hereinafter sometimes referred to as the "antireflection layer of the present invention") preferably contains an inorganic substance. Examples of the above-mentioned inorganic substances include the inorganic substances exemplified and described as materials constituting the high refractive index layer, the low refractive index layer, and the medium refractive index layer described below.

As the anti-reflection layer of the present invention, any appropriate structure can be adopted, for example: (i) a single layer of a low refractive index layer with an optical film thickness of 120 nm to 140 nm and a refractive index of 1.35 to 1.55; (ii) ) A laminated body having a medium refractive index layer, a high refractive index layer and a low refractive index layer in this order; (iii) A multi-layered laminated body having alternating high refractive index layers and low refractive index layers.

Examples of materials capable of forming a low refractive index layer include silicon oxide (SiO ₂ ) and magnesium fluoride (MgF ₂ ). The refractive index of the low refractive index layer is typically about 1.35 to 1.55.

The material of the low refractive index layer may also be a cured product of a curable fluorine-containing resin. The curable fluorine-containing resin has, for example, a structural unit derived from a fluorine-containing monomer and a structural unit derived from a crosslinkable monomer. Specific examples of the fluorine-containing monomer include: fluoroolefins (vinyl fluoride, vinylidene fluoride, tetrafluoroethylene, hexafluoroethylene, hexafluoropropylene, perfluoro-2,2-dimethyl-1 , 3-dioxole, etc.), (meth)acrylate derivatives having a partially or fully fluorinated alkyl group (Viscoat 6FM (manufactured by Osaka Organic Chemical Co., Ltd.), M-2020 (Daikin Corporation Manufacturing), etc.), fully or partially fluorinated vinyl ethers, etc. Examples of crosslinkable monomers include: (meth)acrylate monomers having crosslinkable functional groups in the molecule, such as glycidyl methacrylate; and (meth)acrylate monomers having functions such as carboxyl groups, hydroxyl groups, amino groups, and sulfonic acid groups. Based on (meth)acrylate monomers ((meth)acrylic acid, hydroxymethyl (meth)acrylate, hydroxyalkyl (meth)acrylate, allyl (meth)acrylate, etc.). The fluorine-containing resin may have structural units derived from other monomers (for example, olefin-based monomers, (meth)acrylate-based monomers, and styrene-based monomers) other than the above-mentioned compounds.

Examples of materials capable of forming a high refractive index layer include titanium oxide (TiO ₂ ), niobium oxide (Nb ₂ O ₃ or Nb ₂ O ₅ ), tin-doped indium oxide (ITO), and antimony-doped tin oxide (ATO). , ZrO ₂ -TiO ₂ . The refractive index of the high refractive index layer is typically about 1.60 to 2.40.

Examples of the material capable of forming the medium refractive index layer include titanium oxide (TiO ₂ ), a mixture of a material capable of forming a low refractive index layer and a material capable of forming a high refractive index layer (for example, a mixture of titanium oxide and silicon oxide). . The refractive index of the medium refractive index layer is typically about 1.50 to 1.85. The thickness of the low refractive index layer, the medium refractive index layer and the high refractive index layer can be set in a manner to achieve an appropriate optical film thickness corresponding to the layer structure of the anti-reflective layer, the required anti-reflective performance, etc.

The anti-reflective layer of the present invention can be formed by a dry process (such as sputtering), a wet process (such as coating), or a combination of a dry process and a wet process. Specific examples of the dry process include: PVD (Physical Vapor Deposition) method and CVD (Chemical Vapor Deposition) method. Examples of the PVD method include vacuum evaporation method, reactive evaporation method, ion beam assisted method, sputtering method, and ion plating method. An example of the CVD method is a plasma CVD method.

As a specific example of the wet process, for example, a coating liquid for forming an antireflection layer can be applied to form a coating film, and the coating film can be hardened to form an antireflection layer. As the coating method, coating methods such as injection coating, die coating, spin coating, spray coating, gravure coating, roll coating, and rod coating can be used. Before the above-mentioned hardening, it is preferable to dry the above-mentioned coating film. The above-mentioned drying may be natural drying, air drying by blowing, heating drying, or a combination of these methods. The coating film hardening method is not particularly limited, but ultraviolet curing is preferred.

The thickness of the anti-reflective layer of the present invention is, for example, about 20 nm to 300 nm.

From the viewpoint of antifouling properties, the water contact angle of the anti-reflective layer of the present invention is preferably 90° or more, more preferably 95° or more, further preferably 100° or more, especially 105° or more. The water contact angle of the anti-reflective layer of the present invention is measured according to JIS R3257 and can be adjusted according to the types of components constituting the anti-reflective layer. In addition, the anti-reflective layer of the present invention preferably has a water contact angle within the above range after the following eraser test. By laminating the anti-reflective layer in the water contact corners after the eraser test on the viewing side of the OLED display device, especially the outermost surface, excellent anti-fouling properties can be maintained even after wiping the OLED display device with hands or cloth. sex. ＜Eraser test＞ An eraser for abrasion resistance evaluation "Product No. 4004005007" manufactured by Minoan was cut into 7 mm, and the surface of the hard coating was rubbed back and forth 6,000 times under the conditions of a load of 1 kg and a moving speed of 32 mm/second.

(anti-glare layer) As the anti-glare layer constituting the optical element of the present invention (hereinafter sometimes referred to as the "anti-glare layer of the present invention"), well-known ones can be used without limitation. Generally speaking, the anti-glare layer has an anti-glare layer dispersed in a resin. Formed in the form of layers of inorganic or organic particles.

The anti-glare layer of the present invention is not particularly limited. For example, it is formed using an anti-glare layer-forming material containing a resin, particles, and a thixotropy imparting agent. By agglomerating the above particles and the thixotropy imparting agent, the anti-glare layer of the present invention The surface of the glare layer forms a convex portion. With this structure, the anti-glare layer has excellent display characteristics that combine anti-glare properties and prevent white blur, and even if the anti-glare layer is formed by aggregation of particles, it can also prevent protrusions on the surface of the anti-glare layer that become appearance defects. The production of things improves the yield of products.

Examples of the resin include thermosetting resins and ionizing radiation-curable resins that are cured by ultraviolet rays or light. As the above-mentioned resin, commercially available thermosetting resin, ultraviolet curing resin, etc. can also be used.

As the thermosetting resin or ultraviolet curing resin, for example, a curing compound having at least one of an acrylate group and a methacrylate group that is cured by heat, light (ultraviolet, etc.) or an electron beam can be used. For example, Examples include: silicone resin, polyester resin, polyether resin, epoxy resin, urethane resin, alkyd resin, spiroacetal resin, polybutadiene resin, polythiol polyene resin, polyvalent resin Oligomers or prepolymers of polyfunctional compounds such as alcohols, such as acrylates or methacrylates. These may be used individually by 1 type, and may be used in combination of 2 or more types.

For example, a reactive diluent having at least one group of an acrylate group and a methacrylate group can be used among the above-mentioned resins. The reactive diluent described in Japanese Patent Application Laid-Open No. 2008-88309 can be used, for example, and includes, for example, monofunctional acrylate, monofunctional methacrylate, multifunctional acrylate, and multifunctional methacrylate. wait. As the reactive diluent, a trifunctional or higher functional acrylate and a trifunctional or higher functional methacrylate are preferred. The reason for this is that the anti-glare layer of the present invention can be made to have excellent hardness. Examples of the reactive diluent include butanediol glyceryl ether diacrylate, isocyanuric acid acrylate, isocyanuric acid methacrylate, and the like. These may be used individually by 1 type, and may be used in combination of 2 or more types.

The resin is preferably a copolymer containing a urethane acrylate resin, and more preferably a curable urethane acrylate resin and a multifunctional acrylate (for example, pentaerythritol triacrylate).

The main functions of the particles used to form the anti-glare layer of the present invention are to make the surface of the anti-glare layer to be formed into a concave and convex shape to impart anti-glare properties, and to control the haze value of the anti-glare layer. The haze value of the anti-glare layer can be designed by controlling the refractive index difference between the above-mentioned particles and the above-mentioned resin. Examples of the particles include inorganic particles and organic particles. The above-mentioned inorganic particles are not particularly limited, and examples thereof include silicon oxide particles, titanium oxide particles, aluminum oxide particles, zinc oxide particles, tin oxide particles, zirconium oxide particles, calcium carbonate particles, barium sulfate particles, talc particles, and kaolin particles. Calcium sulfate particles, etc. In addition, the above-mentioned organic particles are not particularly limited, and examples thereof include polymethyl methacrylate resin powder (PMMA fine particles), silicone resin powder, polystyrene resin powder, polycarbonate resin powder, and acrylic styrene resin powder. , benzoguanamine resin powder, melamine resin powder, polyolefin resin powder, polyester resin powder, polyamide resin powder, polyimide resin powder, polyvinyl fluoride resin powder, etc. One type of these inorganic particles and organic particles may be used alone, or two or more types may be used in combination.

The weight average particle diameter (D) of the above-mentioned particles is preferably in the range of 2.5 to 10 μm. By setting the weight average particle diameter of the particles in the above range, for example, anti-glare properties can be further improved and white blur can be prevented. The weight average particle diameter of the above-mentioned particles is more preferably in the range of 3 to 7 μm. In addition, the weight average particle diameter of the said particle|grains can be measured using Coulter counting method, for example. For example, a particle size distribution measuring device using the pore resistance method (trade name: Coulter particle counter, manufactured by Beckman Coulter Co., Ltd.) is used to measure the resistance of the electrolyte solution equivalent to the volume of the particles when the particles pass through the pores, thereby measuring the above-mentioned The number and volume of particles are used to calculate the weight average particle size.

The shape of the above-mentioned particles is not particularly limited. For example, they may be roughly spherical in the form of beads, or may be irregular in shape such as powder. Preferably, they are generally spherical, and more preferably, generally spherical particles with an aspect ratio of 1.5 or less are most preferred. are spherical particles.

The ratio of the above-mentioned particles in the anti-glare layer of the present invention is preferably in the range of 0.2 to 12 parts by weight, more preferably in the range of 0.5 to 12 parts by weight, and further preferably 1 to 7 parts by weight based on 100 parts by weight of the above-mentioned resin. range of shares. By setting it within the above range, for example, the anti-glare property can be further improved and white blur can be prevented.

The anti-glare layer of the present invention may also contain a thixotropic agent. By containing the thixotropy-imparting agent, the aggregation state of the particles can be easily controlled. Examples of the thixotropy-imparting agent used to form the anti-glare layer of the present invention include organoclay, oxidized polyolefin, modified urea, and the like.

In order to improve the affinity with the above-mentioned resin, the above-mentioned organic clay is preferably organically treated clay. Examples of the organoclay include layered organoclay. The above-mentioned organoclay can be prepared by oneself, or commercially available products can be used. Examples of the commercially available products include: Lucentite SAN, Lucentite STN, Lucentite SEN, Lucentite SPN, Somasif ME-100, Somasif MAE, Somasif MTE, Somasif MEE, and Somasif MPE (trade names, all are CO-OP. CHEMICAL (Manufacturing); S-BEN, S-BEN C, S-BEN E, S-BEN W, S-BEN P, S-BEN WX, S-BEN N-400, S-BEN NX, S-BEN NX80, S-BEN NO12S, S-BEN NEZ, S-BEN NO12, S-BEN NE, S-BEN NZ, S-BEN NZ70, ORGANITE, ORGANITE D, ORGANITE T (trade names, all Ho Jun Co., Ltd. Manufacturing); Kunipia F, Kunipia G, Kunipia G4 (trade names, all manufactured by Guofeng Industrial Co., Ltd.); Tixogel VZ, Kraton HT, Kraton 40 (trade names, all manufactured by Rockwood Additives Company), etc.

The above-mentioned oxidized polyolefin can be prepared by oneself, or commercially available products can be used. Examples of the commercially available products include Disparlon 4200-20 (trade name, manufactured by Kusumoto Chemical Co., Ltd.), FLOWNON SA300 (trade name, manufactured by Kyeisha Chemical Co., Ltd.), and the like.

The above-mentioned modified urea is a reaction product of isocyanate monomer or its adduct and organic amine. The above-mentioned modified urea can be prepared by oneself, or commercially available products can be used. Examples of the commercially available product include BYK410 (manufactured by BYK-Chemie Co., Ltd.).

The above-mentioned thixotropy-imparting agent may be used alone or in combination of two or more.

The height of the above-mentioned convex portion from the average roughness line of the anti-glare layer of the present invention is preferably less than 0.4 times the thickness of the anti-glare layer. More preferably, it is in the range of 0.01 times or more and less than 0.4 times, and still more preferably, it is in the range of 0.01 times or more and less than 0.3 times. If it is within this range, it is possible to preferably prevent the formation of protrusions that cause appearance defects on the convex portions. The anti-glare layer of the present invention can make appearance defects less likely to occur by having convex portions with such a height. Here, the height from the average line can be measured, for example, by the method described in Japanese Patent Application Laid-Open No. 2017-138620.

The ratio of the thixotropy-imparting agent in the anti-glare layer of the present invention is preferably in the range of 0.1 to 5 parts by weight, and more preferably in the range of 0.2 to 4 parts by weight based on 100 parts by weight of the resin.

The thickness (d') of the anti-glare layer of the present invention is not particularly limited, but is preferably in the range of 2 to 12 μm. By setting the thickness (d′) of the anti-glare layer to the above range, for example, the optical laminate of the present invention can be prevented from curling, and problems such as poor transportability and reduced productivity can be avoided. In addition, when the thickness (d') falls within the above range, the weight average particle diameter (D) of the particles is as described above, and preferably falls within the range of 2.5 to 10 μm. The thickness (d') of the anti-glare layer of the present invention and the weight average particle diameter (D) of the above-mentioned particles can be used in the above combination to achieve more excellent anti-glare properties. The thickness (d') of the anti-glare layer of the present invention is preferably in the range of 2 to 10 μm, and further preferably in the range of 3 to 8 μm.

The relationship between the thickness (d') of the anti-glare layer of the present invention and the weight average particle diameter (D) of the above-mentioned particles is preferably within the range of 0.3≦D/d'≦0.9. By having such a relationship, the anti-glare property can be further improved, white blur can be prevented, and an anti-glare layer without appearance defects can be produced.

The haze value (H') of the anti-glare layer of the present invention is not particularly limited. From the perspective of effectively reducing color shift or interference spots in the OLED display device, it is preferably 5% or more, and more preferably 10%. or above, more preferably 15% or more, particularly preferably 20% or more. Furthermore, from the viewpoint of suppressing image blurring of the OLED display device and displaying high-definition images, the haze value of the anti-glare layer of the present invention is preferably 80% or less, more preferably 70% or less, and even more preferably 60%. % or less, preferably less than 50%.

The haze value of the anti-glare layer of the present invention can be measured according to the method specified in JIS K 7136, and can be designed by controlling the type or thickness of the anti-glare layer and the refractive index difference between the above-mentioned particles and the above-mentioned resin.

The anti-glare layer of the present invention forms convex portions on the surface of the anti-glare layer of the present invention by aggregation of the above-mentioned particles and the above-mentioned thixotropy imparting agent. In the aggregation part forming the above-mentioned convex part, the above-mentioned particles exist in a state of aggregating a plurality of particles in the surface direction of the anti-glare layer of the present invention. Thereby, the above-mentioned convex part becomes a gentle shape. The anti-glare layer of the present invention can maintain anti-glare properties and prevent white blur by having convex portions of such a shape, thereby making appearance defects less likely to occur.

The surface shape of the anti-glare layer of the present invention can be arbitrarily designed by controlling the aggregation state of particles contained in the anti-glare layer forming material. The aggregation state of the particles can be controlled, for example, based on the material of the particles (such as the chemical modification state of the particle surface, affinity for solvents or resins, etc.), the type and combination of resin (binder) or solvent, and the like. Here, the aggregation state of the particles can be controlled by the thixotropy imparting agent contained in the anti-glare layer forming material of the present invention. As a result, the aggregation state of the said particles can be made as mentioned above, and the said convex part can be made into a gentle shape.

In the anti-glare layer of the present invention, it is preferable that the number of appearance defects with a maximum diameter of 200 μm or more is less than 1 per 1 m ² of the anti-glare layer. It is better to have no appearance defects mentioned above.

Regarding the uneven shape of the anti-glare layer surface of the present invention, the average inclination angle θa (°) is preferably in the range of 0.1 to 5.0, more preferably in the range of 0.3 to 4.5, further preferably in the range of 1.0 to 4.0, and particularly preferably 1.6～4.0. Here, the above-mentioned average tilt angle θa is a value defined by the following equation (1). The above-mentioned average tilt angle θa is a value measured by the method described in Japanese Patent Application Laid-Open No. 2017-138620, for example. Average tilt angle θa=tan-1Δa (1)

In the above equation (1), Δa is as shown in the following equation (2). In the reference length L of the roughness curve specified in JIS B0601 (1994 edition), Δa is the difference between the top of the adjacent peak and the lowest point of the valley. The value obtained by dividing the total (height h) (h1＋h2＋h3・・・＋hn) by the above-mentioned reference length L. The above-mentioned roughness curve is a curve obtained by removing surface undulation components longer than a specified wavelength from the cross-sectional curve using a phase difference compensation type high-pass filter. In addition, the above-mentioned cross-sectional curve is the outline of the incision that appears when the object surface is cut by a plane at right angles to the object surface. Δa＝(h1＋h2＋h3・・・＋hn)/L (2)

When θa falls within the above range, anti-glare properties can be further improved and white blur can be prevented.

When forming the anti-glare layer of the present invention, it is preferable that the prepared anti-glare layer forming material (coating liquid) exhibits thixotropy, and it is preferable that the Ti value specified below falls within the range of 1.3 to 3.5, more preferably 1.3 ~2.8 range. Ti value=β1/β2 Here, β1 is the viscosity measured using Rheo Stress 6000 manufactured by HAAKE Company at a shear rate of 20 (1/s), and β2 is the viscosity measured using Rheo Stress 6000 manufactured by HAAKE Company at a shear rate of 200 ( The viscosity measured under the condition of 1/s).

If the Ti value is less than 1.3, appearance defects are likely to occur, and anti-glare properties and white blur properties will deteriorate. Moreover, if the Ti value exceeds 3.5, the above-mentioned particles are less likely to agglomerate and are likely to be in a dispersed state.

The manufacturing method of the anti-glare layer of the present invention is not particularly limited and can be manufactured by any method. For example, it can be prepared by preparing an anti-glare layer forming material (coating liquid) containing the above-mentioned resin, the above-mentioned particles, the above-mentioned thixotropy imparting agent and a solvent. ), the above-mentioned anti-glare layer forming material (coating liquid) is applied to form a coating film, and the above-mentioned coating film is cured to form an anti-glare layer, thereby manufacturing. A method of imparting a concave and convex shape by a transfer method using a mold, or a suitable method such as sandblasting or an embossing roller can also be used.

The above-mentioned solvent is not particularly limited, and various solvents can be used. One type of solvent may be used alone, or two or more types of solvents may be used in combination. There is an optimal solvent type or solvent ratio depending on the composition of the resin, the type, content, etc. of the particles and the thixotropy-imparting agent. The solvent is not particularly limited, and examples thereof include: methanol, ethanol, isopropyl alcohol, butanol, 2-methoxyethanol alcohols; acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclopentanone, etc. Ketones; esters such as methyl acetate, ethyl acetate, butyl acetate; ethers such as diisopropyl ether, propylene glycol monomethyl ether; glycols such as ethylene glycol and propylene glycol; ethyl cellosolve, butyl cellosolve and other cellosolve agents; aliphatic hydrocarbons such as hexane, heptane, and octane; aromatic hydrocarbons such as benzene, toluene, and xylene, etc.

By appropriately selecting the above solvent, the thixotropy of the anti-glare layer forming material (coating liquid) by the thixotropy-imparting agent can be well expressed. For example, when organoclay is used, toluene and xylene can be suitably used alone or in combination. For example, when oxidized polyolefin is used, methyl ethyl ketone, ethyl acetate, or propylene glycol can be suitably used alone or in combination. Methyl ether, for example, when using modified urea, can be suitably used alone or in combination with butyl acetate and methyl isobutyl ketone.

Various leveling agents can be added to the anti-glare layer forming material. As the above-mentioned leveling agent, in order to prevent uneven coating (uniformization of the coating surface), for example, a fluorine-based or silicone-based leveling agent can be used. An appropriate leveling agent can be selected depending on the situation where antifouling properties are required on the surface of the anti-glare layer of the present invention, or when an anti-reflective layer or a layer containing an interlayer filler is formed on the anti-glare layer. For example, by including the thixotropy-imparting agent described above, the coating liquid can express thixotropy, so that coating unevenness is less likely to occur. Therefore, for example, there is the advantage of expanding the options of the above-mentioned leveling agent.

The blending amount of the above-mentioned leveling agent is, for example, 5 parts by weight or less, preferably in the range of 0.01 to 5 parts by weight, based on 100 parts by weight of the above-mentioned resin.

Pigments, fillers, dispersants, plasticizers, ultraviolet absorbers, surfactants, antifouling agents, antioxidants, etc. may also be added to the above-mentioned anti-glare layer forming materials as necessary within the scope of non-impairment of performance. These additives may be used individually by 1 type, or may use 2 or more types together.

As the anti-glare layer forming material, a conventionally known photopolymerization initiator described in Japanese Patent Application Laid-Open No. 2008-88309 can be used, for example.

As a method of applying the anti-glare layer forming material, for example, a spray coating method, a die coating method, a spin coating method, a spray coating method, a gravure coating method, a roller coating method, a rod coating method, etc. can be used. Application method.

The anti-glare layer forming material is applied to form a coating film, and the coating film is hardened. It is preferable to dry the said coating film before said hardening. The above-mentioned drying can be, for example, natural drying, air drying by blowing, heating drying, or a combination of these methods.

The method of curing the coating film of the anti-glare layer forming material is not particularly limited, but ultraviolet curing is preferred. The irradiation dose of the energy ray source is calculated as the cumulative exposure dose at the ultraviolet wavelength of 365 nm, and is preferably 50 to 500 mJ/cm ² . If the irradiation dose is 50 mJ/cm ² or more, the hardening becomes more sufficient, and the hardness of the formed anti-glare layer also becomes more sufficient. In addition, if it is 500 mJ/cm ² or less, discoloration of the formed anti-glare layer can be prevented.

The anti-glare layer of the present invention can be formed as described above. Furthermore, the anti-glare layer can also be formed using a manufacturing method other than the above-mentioned method. Regarding the hardness of the anti-glare layer of the present invention, the pencil hardness is also affected by the thickness of the layer, and preferably has a hardness of 2H or above.

The anti-glare layer of the present invention may also have a multi-layer structure in which two or more layers are laminated.

The above-mentioned anti-reflective layer can also be disposed on the anti-glare layer of the present invention. For example, one of the factors causing the decrease in visibility of the OLED display device is light reflection at the interface between the air and the anti-glare layer. The anti-reflective layer is a layer that reduces the reflection of the surface. Furthermore, the anti-glare layer and the anti-reflective layer of the present invention may each have a multi-layer structure in which two or more layers are laminated.

(middle layer) The intermediate layer constituting the optical element of the present invention (hereinafter sometimes referred to as the "intermediate layer of the present invention") is a layer formed between the above-mentioned resin layer and the above-mentioned hard coat layer, anti-reflection layer, or anti-glare layer. By forming this intermediate layer, the adhesion between the resin layer and the above-mentioned hard coat layer, anti-reflection layer, or anti-glare layer is improved.

The formation mechanism of the intermediate layer (also known as the permeability layer and the compatible layer) of the present invention is not particularly limited. For example, in the formation of the above-mentioned hard coating layer, anti-reflection layer, or anti-glare layer, the hard coating layer is formed with a coating. The coating liquid, the coating liquid for forming the anti-reflective layer, or the coating liquid for forming the anti-glare layer is formed in the process of coating, penetrating, and drying on the resin layer. In the above-mentioned drying step, for example, the coating liquid for forming the hard coat layer, the coating liquid for forming the anti-reflective layer, or the coating liquid for forming the anti-glare layer is allowed to penetrate into the resin layer to form a layer containing the resin derived from the resin layer and the coating liquid derived from the resin layer. The above-mentioned intermediate layer of resin is a hard coat layer, an anti-reflective layer, or an anti-glare layer. The resin contained in the above-mentioned intermediate layer is not particularly limited. For example, the resin contained in the resin layer may be simply mixed (compatible) with the resin contained in the hard coat layer, anti-reflective layer, or anti-glare layer. In addition, the resin contained in the above-mentioned intermediate layer, for example, at least one of the resin contained in the resin layer and the resin contained in the hard coat layer, anti-reflective layer, or anti-glare layer can undergo chemical changes by heating, light irradiation, etc. .

The thickness ratio R of the above-mentioned intermediate layer defined by the following formula (3) is not particularly limited, and is, for example, 0.10 to 0.80. For example, it can be 0.15 or more, 0.20 or more, 0.25 or more, 0.30 or more, 0.40 or more, or 0.45 or more. For example, it may be 0.75 or less, 0.70 or less, 0.65 or less, 0.60 or less, 0.50 or less, 0.40 or less, 0.45 or less, or 0.30 or less. The thickness ratio R of the above-mentioned intermediate layer may be, for example, 0.15~0.75, 0.20~0.70, 0.25~0.65, 0.30~0.60, 0.40~0.50, 0.45~0.50, 0.15~0.45, 0.15~0.40, 0.15~0.30, or 0.20~0.30. . The above-mentioned intermediate layer can be confirmed by observing the cross section of the optical element using a transmission electron microscope (TEM), for example, and the thickness can be measured. R＝[DC/(DC＋DB)]   (3) In the above formula (3), DB is the thickness [μm] of the hard coat layer, anti-reflection layer, or anti-glare layer, and DC is the thickness [μm] of the above-mentioned intermediate layer.

When an intermediate layer is formed between the resin layer and the hard coat layer, the anti-reflective layer, or the anti-glare layer, from the viewpoint of excellent adhesion, the resin layer and the hard coat layer, the anti-reflective layer, or the anti-glare layer The shear failure strength between layers is preferably 20 MPa or more, more preferably 50 MPa or more. The above-mentioned shear failure strength can be determined by the SAICAS (Surface And Interfacial Cutting Analysis System) method, and can be determined according to the type of resin layer, the coating liquid for forming the hard coat layer, and the coating for forming the anti-reflective layer. The composition of the coating liquid or the film forming method for forming the anti-glare layer should be adjusted.

(impact absorbing layer) The impact-absorbing layer constituting the optical element of the present invention (hereinafter sometimes referred to as the "impact-absorbing layer of the present invention") can be composed of any appropriate resin layer that can achieve a desired impact-absorbing rate. The resin layer may be composed of a resin film or an adhesive. The impact-absorbing layer typically contains an epoxy resin, a urethane resin, or an acrylic resin. These resins can be used alone or in combination.

The thickness of the impact absorbing layer of the present invention is preferably 30 μm to 200 μm, more preferably 30 μm to 150 μm, and further preferably 40 μm to 120 μm. If the thickness of the impact-absorbing layer of the present invention is within this range, an optical laminate having excellent impact resistance can be realized.

The storage elastic modulus G' of the impact absorbing layer of the present invention at 25°C is preferably 0.1 GPa or less, more preferably 0.01 MPa to 0.1 GPa. If the storage elastic modulus of the impact-absorbing layer of the present invention is within this range, it has the advantage of absorbing impact and preventing cracking of the optical laminate. Furthermore, a synergistic effect with the above-mentioned thickness effect can also be exerted.

(Antistatic layer) The antistatic layer constituting the optical element of the present invention (hereinafter sometimes referred to as the "antistatic layer of the present invention") is not particularly limited. For example, it is an antistatic layer formed by applying a conductive coating liquid containing a conductive polymer. . Specific coating methods include roll coating, bar coating, gravure coating, and the like.

Examples of the conductive polymer include a conductive polymer in which a π-conjugated conductive polymer is doped with polyanions. Examples of the π-conjugated conductive polymer include chain conductive polymers such as polythiophene, polypyrrole, polyaniline, and polyacetylene. Examples of the polyanion include polystyrene sulfonic acid, polyisoprene sulfonic acid, polyvinyl sulfonic acid, polyallylsulfonic acid, polyacrylic acid ethyl sulfonic acid, polymethacrylic acid carboxylic acid, and the like.

The thickness of the above antistatic layer is preferably 1 nm to 1000 nm, more preferably 5 nm to 900 nm. The above-mentioned antistatic layer may be only one layer, or may be two or more layers.

(Optical laminated body) Regarding the optical laminated body of the present invention, in the reflectance spectrum of the above-mentioned OLED display device in a state where the above-mentioned optical laminated body for OLED display devices is not laminated, when the maximum value at a wavelength of 380 to 455 nm is taken as Rp1, the above-mentioned Rp1 When the reflectivity of the anti-reflection layer at the wavelength (WL1) is Rf1, [Rf1/Rp1] is preferably 0.3 or less, more preferably 0.25 or less, further preferably 0.2 or less, still more preferably 0.15 or less. , especially preferably below 0.1. The smaller the above-mentioned [Rf1/Rp1] is, the further the interference spots are suppressed.

Regarding the optical laminated body of the present invention, in the reflectance spectrum of the above-mentioned OLED display device in a state where the above-mentioned optical laminated body for OLED display devices is not laminated, when the maximum value at a wavelength of 460 to 530 nm is taken as Rp2, the above-mentioned Rp2 When the reflectivity of the anti-reflection layer at the wavelength (WL2) is Rf2, [Rf2/Rp2] is 0.12 or less, more preferably 0.1 or less, further preferably 0.05 or less, still more preferably 0.03 or less, Particularly preferably, it is 0.01 or less. The smaller the above-mentioned [Rf2/Rp2] is, the further the interference spots are suppressed.

Furthermore, in this specification, the wavelength WL1 is, for example, 430 nm or 440 nm, and the wavelength WL2 is, for example, 500 nm or 510 nm. Moreover, each of Rp1 and Rp2 is, for example, 7% or more (for example, 7 to 20%), preferably 10% or more (for example, 10 to 18%).

The total of the above-mentioned [Rf1/Rp1] and the above-mentioned [Rf2/Rp2] is preferably 0.42 or less, more preferably 0.4 or less, further preferably 0.3 or less, still more preferably 0.2 or less, especially 0.1 or less. The smaller the above total, the further the interference spots are suppressed.

The optical laminated body of the present invention preferably has a structure in which the hard coat layer of the present invention, the base material layer, and the adhesive layer of the present invention are provided on the side opposite to the viewing side of the anti-reflection layer of the present invention. It is preferable to have a structure having these layers in sequence. The resin layer of the present invention or the glass layer of the present invention can be used as the base material layer.

In one embodiment of the optical laminated body of the present invention (such as the optical laminated body in the OLED display device of the present invention shown in FIGS. 3 and 4 below), it is preferable to have the adhesive layer of the present invention (especially A structure in which an adhesive layer with light scattering properties is provided on at least one side of the resin layer of the present invention. In this case, let the refractive index of the resin layer of the present invention be n1, the refractive index of the adhesive of the adhesive layer of the present invention be n2, and the refractive index of the light-scattering fine particles of the present invention be n3. When , it is better to satisfy n1>n2>n3. In this case, white blur is further suppressed.

In one embodiment of the optical laminate of the present invention (for example, the optical laminate in the OLED display device of the present invention shown in FIGS. 3 and 4 below), the refractive index (n1) of the resin layer of the present invention is preferably It is 1.50-1.80, More preferably, it is 1.55-1.75, Still more preferably, it is 1.60-1.70. The refractive index of the above-mentioned resin layer can be adjusted according to the type, content, etc. of the resin constituting the resin layer.

In one embodiment of the optical laminated body of the present invention (for example, the optical laminated body in the OLED display device of the present invention shown in FIGS. 3 and 4 below), it is preferable to have a layer located on one side of the resin layer of the present invention. The adhesive layer of the present invention (especially the adhesive layer with light scattering properties) has the structure of the hard coating layer of the present invention on the other side. In this embodiment, it is particularly preferable to satisfy n1>n2>n3.

In one embodiment of the optical laminated body of the present invention (for example, the optical laminated body in the OLED display device of the present invention shown in FIGS. 5 to 7 below), a color filter is arranged on the viewing side of the OLED element, And when the distance (d) between the adhesive layer of the present invention and the above-mentioned color filter is 700 μm or less, the adhesive layer of the present invention (especially the adhesive layer with light scattering properties) and the above-mentioned color filter The distance between the filters is set to d [μm], and the haze value of the adhesive layer of the present invention (especially the adhesive layer with light scattering properties) is set to H [%], preferably d × The value of H is 70,000 or less, more preferably 60,000 or less, still more preferably 50,000 or less. If the value of d×H is below 700000, image blur is less likely to occur. The value of d×H is, for example, 100 or more, and may be 1,000 or more, 10,000 or more, or 20,000 or more. In this case, H is preferably 20 or more.

In one embodiment of the optical laminated body of the present invention (for example, the optical laminated body in the OLED display device of the present invention shown in FIGS. 5 to 7 below), the adhesive layer of the present invention (especially having light scattering When the thickness of the adhesive layer of the present invention (especially the adhesive layer with light scattering properties) is set to T [μm] and the haze value of the adhesive layer of the present invention (especially the adhesive layer with light scattering properties) is set to H [%], it is preferably T The value of If the value of T×H is below 400, image blur is less likely to occur. The value of T×H is, for example, 10,000 or less, or may be 8,000 or less, 6,000 or less, or 4,000 or less.

In one embodiment of the optical laminated body of the present invention (for example, the optical laminated body in the OLED display device of the present invention shown in FIGS. 8 to 10 below), in a state where the optical laminated body for an OLED display device is not laminated. In the reflectance spectrum of the above-mentioned OLED display device, when the scattering efficiency of the anti-glare layer of the present invention at the wavelength WL1 of the maximum value in the display wavelength of 380 to 455 nm is set to S1, S1 is preferably 15% or more, more preferably It is 20% or more, more preferably 30% or more, still more preferably 40% or more, especially 50% or more. The larger the above-mentioned S1 is, the further the interference spots are suppressed.

In one embodiment of the optical laminated body of the present invention (for example, the optical laminated body in the OLED display device of the present invention shown in FIGS. 8 to 10 below), in a state where the optical laminated body for the OLED display device is not laminated. In the reflectance spectrum of the above-mentioned OLED display device, when the scattering efficiency of the anti-glare layer of the present invention at the wavelength WL2 of the maximum display wavelength of 460 to 530 nm is set to S2, S2 is preferably 15% or more, more preferably It is 20% or more, more preferably 30% or more, still more preferably 40% or more, especially 50% or more. The larger the above-mentioned S2 is, the further the interference spots are suppressed.

Regarding the above-mentioned scattering efficiencies S1 and S2, the transmittance at a predetermined wavelength measured in a state in which the optical laminate with the anti-glare layer of the present invention is in contact with the integrating sphere is assumed to be Tn1. When the transmittance at the above specified wavelength measured with the laminated body placed at a distance of 145 mm from the integrating sphere is set to Tn2, it is calculated as Tn1-Tn2.

The total of the above-mentioned S1 and the above-mentioned S2 is preferably 30% or more, more preferably 40% or more, further preferably 60% or more, further preferably 80% or more, and particularly preferably 100% or more. The larger the above total, the further the interference spots are suppressed.

In one embodiment of the optical laminated body of the present invention (for example, the optical laminated body in the OLED display device of the present invention shown in the following FIGS. 8 to 10), it is preferable to have an anti-glare layer of the present invention and visual recognition. The opposite side has a base material layer and an adhesive layer of the present invention, and more preferably has a structure in which these layers are provided in sequence. The resin layer of the present invention or the glass layer of the present invention can be used as the base material layer.

In one embodiment of the optical laminated body of the present invention (for example, the optical laminated body in the OLED display device of the present invention shown in FIGS. 14 and 15 below), it is preferable to have an optical layer on the viewing side of the glass layer of the present invention. Furthermore, the optical element of the present invention has a structure including the adhesive layer, the base layer, and the hard coat layer of the present invention, and more preferably has a structure including these layers in order. The resin layer of the present invention or the glass layer of the present invention can be used as the base material layer.

In one embodiment of the optical laminate of the present invention (for example, the optical laminate in the OLED display device of the present invention shown in FIGS. 14 and 15 below), the press-fit elastic modulus of the adhesive layer of the present invention is When Ea is set and the tensile storage elastic modulus of the resin layer of the present invention is set to Er, the absolute value of Ea-Er is preferably 1 GPa or less, more preferably 0.9 GPa or less, and further preferably 0.7 GPa or less. Particularly preferably, it is below 0.5 GPa. If the above absolute value is 1 GPa or less, the impact resistance will be further improved.

In one embodiment of the optical laminate of the present invention (for example, the optical laminate in the OLED display device of the present invention shown in FIGS. 14 and 15 below), the tensile storage elastic modulus Er of the resin layer of the present invention is It is preferably 4 GPa or more, more preferably 4.3 GPa or more, and still more preferably 4.6 GPa or more. If the above-mentioned tensile storage elastic modulus Er is 4 GPa or more, the impact resistance will be further improved. The tensile storage elastic modulus Er may be, for example, 50 GPa or less, 30 GPa or less, or 10 GPa or less. The above-mentioned tensile storage elastic modulus Er can be measured in accordance with JIS K 7161.

In one embodiment of the optical laminate of the present invention (for example, the optical laminate in the OLED display device of the present invention shown in FIGS. 16 and 17 below), it is preferable to have the transparent polyimide layer and The present invention has a structure in which an intermediate layer (compatibility layer) is formed between the hard coat layers. By forming the above-mentioned intermediate layer, the adhesion between the transparent polyimide layer and the hard coat layer of the present invention is improved. The above-mentioned intermediate layer is a layer formed by penetrating the above-mentioned transparent polyimide layer into the composition (coating agent) for forming the hard coat layer of the present invention. That is, the intermediate layer is a portion of the transparent polyimide layer in which the hard coat component of the present invention is present.

The ratio (P1) of the shear failure strength of the intermediate layer to the shear failure strength of the hard coat layer of the present invention is preferably 0.25 or less, more preferably 0.23, and still more preferably 0.21 or less. The ratio (P1) may be, for example, 0.02 or more, 0.05 or more, or 0.08 or more.

In one embodiment of the optical laminate of the present invention (for example, the optical laminate in the OLED display device of the present invention shown in FIGS. 16 and 17 below), the shear fracture strength of the transparent polyimide layer is relatively The shear failure strength ratio (P2) of the hard coating layer of the present invention is preferably 0.65 or more, more preferably 0.70 or more, further preferably 0.80 or more, and particularly preferably 0.90 or more. The ratio (P2) may be, for example, 1.50 or less, 1.30 or less, or 1.10 or less.

The difference (P2-P1) between the above-mentioned ratio (P1) and the above-mentioned ratio (P2) is preferably 0.6 or more, more preferably 0.70 or more, and may be 0.80 or more. The difference (P2-P1) is, for example, 1.5 or less, 1.2 or less, or 0.9 or less.

In one embodiment of the optical laminated body of the present invention (for example, the optical laminated body in the OLED display device of the present invention shown in FIGS. 16 and 17 below), it is preferable to have the above-mentioned transparent polyimide layer. The opposite side to the hard coat layer of the present invention further has a structure of an adhesive layer.

(Method for manufacturing optical laminate) The manufacturing method of the optical laminated body of the present invention is not particularly limited, and can be achieved by combining the adhesive layer, adhesive layer, resin layer, glass layer, hard coat layer, anti-reflective layer, and anti-glare layer that constitute the optical element of the present invention. , an intermediate layer (compatibility layer), an impact-absorbing layer, etc. are sequentially laminated on the viewing side of the OLED display panel of the present invention. Alternatively, the laminated body constituting the optical laminated body of the present invention can be produced in advance and laminated on the OLED display panel of the present invention. The invented OLED display panel is manufactured based on the visual recognition side. When the laminated body constituting the optical laminated body of the present invention is produced in advance, the laminated body constituting the entire optical laminated body of the present invention may be divided into parts and laminated on The viewing side of the OLED display panel of the present invention.

The layers constituting the optical element of the present invention, or the laminate thereof, may be protected by a release liner or a surface protective film before use.

(release liner) When the optical element of the present invention includes an adhesive layer, a release liner can be provided on the surface (adhesive surface) of the adhesive layer before use. The release liner can be used as a protective material for the adhesive layer and can be peeled off when it is attached to the adherend. Furthermore, if the release liner is not an optical element constituting the present invention, it does not need to be provided.

As the release liner, conventional release paper and the like can be used without particular limitation. Examples thereof include a base material having a release treatment layer, a low-adhesion base material containing a fluoropolymer, or a low-adhesion base material containing a non-polar polymer. Sexual substrates, etc. Examples of the base material having a release treatment layer include a plastic film or paper surface-treated with release treatment agents such as silicone-based, long-chain alkyl-based, fluorine-based, and molybdenum sulfide. Examples of the fluorine-based polymer in the low-adhesion base material containing a fluoropolymer include polytetrafluoroethylene, polychlorotrifluoroethylene, polyvinyl fluoride, polyvinylidene fluoride, and tetrafluoroethylene-hexafluoroethylene. Propylene copolymer, chlorofluoroethylene-vinylidene fluoride copolymer, etc. Examples of the nonpolar polymer include olefin-based resins (eg, polyethylene, polypropylene, etc.). Furthermore, the release liner can be formed by a known or conventional method. In addition, the thickness of the release liner is not particularly limited.

(Surface protective film) The outermost surface (the outermost surface on the viewing side) of the optical laminate of the present invention may be protected by a surface protective film. The surface protective film can be applied by the consumer. Furthermore, if the surface protective film does not constitute the optical element of the present invention, it does not need to be provided.

As the above-mentioned surface protective film, a well-known or commonly used surface protective film can be used without particular limitation. For example, a plastic film having an adhesive layer on its surface can be used. Examples of the plastic film include polyester (polyethylene terephthalate, polyethylene naphthalate, etc.), polyolefin (polyethylene, polypropylene, cyclic polyolefin, etc.), polyethylene Styrene, acrylic resin, polycarbonate, epoxy resin, fluororesin, silicone resin, diacetate resin, triacetate resin, polyarylate, polyvinyl chloride, polystyrene, polyether styrene, polyether Plastic films made of plastic materials such as etherimide, polyimide, and polyamide. Examples of the adhesive layer include acrylic adhesives, natural rubber adhesives, synthetic rubber adhesives, ethylene-vinyl acetate copolymer adhesives, and ethylene-(meth)acrylate copolymers. It is an adhesive layer formed of one or more types of well-known or commonly used adhesives such as adhesive, styrene-isoprene block copolymer adhesive, and styrene-butadiene block copolymer adhesive. The above-mentioned adhesive layer may contain various additives (such as antistatic agents, slip agents, etc.). Furthermore, the plastic film and the adhesive layer may each have a single-layer structure or may have a multi-layer (multi-layer) structure. In addition, the thickness of the surface protective film is not particularly limited and can be appropriately selected.

(OLED display device of the present invention) Hereinafter, one embodiment of an OLED display device in which the optical laminate of the present invention is laminated on the viewing side of the OLED display panel will be described with reference to the drawings. However, the present invention is not limited to this embodiment. FIG. 2 is a schematic cross-sectional view showing one embodiment of the basic structure of an OLED display device in which the optical laminate of the present invention is laminated.

As shown in FIG. 2 , the OLED display device 200 has layers constituting the optical layered body 20 laminated on the viewing side of the OLED display panel 100 (the upper side in FIG. 2 ). The OLED display panel 100 is not particularly limited. For example, the OLED display panel 100 may have the same structure as the OLED display panel 100 shown in FIG. 1 .

In the OLED display device 200 of FIG. 2 , 21 to 29 are layers constituting the optical laminate 20 , 21 represents an adhesive layer or adhesive layer, 22 represents a resin layer, a glass layer or an impact absorbing layer, and 23 represents a hard coat layer or Anti-glare layer, 24 represents the adhesive layer or adhesive layer, 25 represents the resin layer, glass layer or impact-absorbing layer, 26 represents the adhesive layer or adhesive layer, 27 represents the resin layer, glass layer or impact-absorbing layer, 28 represents Hard coating or anti-glare layer, 29 represents anti-reflective layer. The laminated structure of the optical laminated body 20 shown in FIG. 2 is not limited to this embodiment. Other layers constituting the optical element of the present invention may be inserted between any layers of the laminated structure of the optical laminated body 20 shown in FIG. 2 . Any layer in the laminated structure of the optical laminated body 20 shown in FIG. 2 may not be present.

As a preferred embodiment of the present invention, in Figure 2, 24 is an adhesive layer or adhesive layer, 25 is a resin layer, glass layer or impact absorbing layer, 26 is an adhesive layer or adhesive layer, and 27 is a resin layer. , glass layer or impact absorbing layer, 28 is a hard coating or anti-glare layer, 21 to 23 are not present, and at least one of the adhesive layers 24 and 26 is an adhesive layer with light scattering properties. The OLED display device 300A of this embodiment is shown in FIG. 3 . In Figure 3, 34A to 38A are layers constituting the optical laminate 30A, 34A is an adhesive layer or adhesive layer, 35A is a glass layer, 36A is an adhesive layer with light scattering properties, 37A is a resin layer, and 38A is a hard coating. By providing the adhesive layer 36A with light scattering properties, color shift and interference spots caused by the OLED display panel 100 are suppressed, and the OLED display device 300 has excellent visibility. Furthermore, in the OLED display device 300A shown in FIG. 3 , an anti-reflective layer may also be present on the viewing side of the hard coating layer 38A.

As a preferred embodiment of the present invention, in Figure 2, 21 is an adhesive layer, 22 is a resin layer, 23 is a hard coat layer, 24 is an adhesive layer, 25 is a glass layer, 26 is an adhesive layer, and 27 is The resin layer 28 is a hard coating layer, and there is no anti-reflective layer 29. At least one of the adhesive layers 21, 24, and 26 is an adhesive layer with light scattering properties. The OLED display device 300B of this embodiment is shown in FIG. 4 . In Figure 4, 31B to 38B are layers constituting the optical laminate 30B. 31B is an adhesive layer, 32B is a resin layer, 33B is a hard coat layer, 34B is an adhesive layer, 35B is a glass layer, and 36B is a layer with light scattering properties. As for the adhesive layer, 37B is the resin layer and 38B is the hard coat layer. By providing the adhesive layer 36B with light scattering properties, color shift and interference spots caused by the OLED display panel 100 are suppressed, and the OLED display device 300B has excellent visibility. Furthermore, in the OLED display device 300B shown in FIG. 4 , an anti-reflective layer may also be present on the viewing side of the hard coating layer 38B.

As another preferred embodiment of the present invention, in Figure 2, a color filter is disposed on the viewing side of the OLED display panel 100. 26 is an adhesive layer with light scattering properties, 27 is a resin layer, and 28 is a hard coating. Layers 21 to 25 and 29 do not exist, and the distance d (μm) between the adhesive layer 26 with light scattering properties and the color filter is 700 μm or less. By setting the distance d between the adhesive layer with light scattering properties and the color filter to be 700 μm or less, even if a light scattering layer is stacked in order to suppress color shift or interference spots caused by the OLED display device 300, patterns will not easily occur. The image is blurry and the visibility is excellent. The OLED display device 400A of this embodiment is shown in FIG. 5 . In FIG. 5 , 46A to 48A are layers constituting the optical laminated body 40A, 46A is an adhesive layer having light scattering properties, 47A is a resin layer, and 48A is a hard coat layer. 15A is a color filter arranged on the viewing side (upper side in FIG. 5 ) of the OLED display panel 400A. The adhesive layer 46A with light scattering properties is directly connected to the color filter 15A. That is, the distance between the adhesive layer 46A with light scattering properties and the color filter 15A is 0 μm. Therefore, the most efficient The color shift or interference spots caused by the OLED display device 400A are effectively suppressed. Furthermore, in the OLED display device 400A shown in FIG. 5 , an anti-reflective layer may also be present on the viewing side of the hard coating layer 48A.

As another preferred embodiment of the present invention, in Figure 2, a color filter is disposed on the viewing side of the OLED display panel 100. 24 is an adhesive layer with light scattering properties, 25 is a glass layer, and 26 is an adhesive. layer or adhesive layer, 27 is a resin layer, 28 is a hard coating layer, 21 to 23 and 29 are not present, and the distance d (μm) between the adhesive layer 24 with scattering characteristics and the color filter is 700 μm or less. By setting the distance d between the adhesive layer with light scattering properties and the color filter to be 700 μm or less, even if a light scattering layer is stacked in order to suppress color shift or interference spots caused by the OLED display device 300, patterns will not easily occur. The image is blurry and the visibility is excellent. The OLED display device 400B of this embodiment is shown in FIG. 6 . In FIG. 6 , 44B to 48B are layers constituting the optical laminate 40B, 44B is an adhesive layer having light scattering properties, 44B is an adhesive layer having light scattering properties, 45B is a glass layer, and 46B is an adhesive layer or adhesive layer. agent layer, 47B is the resin layer, and 48B is the hard coat layer. 15B is a color filter arranged on the viewing side (upper side in FIG. 6 ) of the OLED display panel 400B. The adhesive layer 44B with light scattering properties is directly connected to the color filter 15B. That is, the distance between the adhesive layer 44B with light scattering properties and the color filter 15B is 0 μm. Therefore, the most efficient The color shift or interference spots caused by the OLED display device 400B are effectively suppressed. Furthermore, in the OLED display device 400B shown in FIG. 6 , an anti-reflective layer may also be present on the viewing side of the hard coating layer 48B.

As another preferred embodiment of the present invention, in Figure 2, a color filter is disposed on the viewing side of the OLED display panel 100. 21 is an adhesive layer, 22 is a resin layer, 23 is a hard coating layer, and 24 is an adhesive layer. agent layer, 25 is a glass layer, 26 is an adhesive layer, 27 is a resin layer, 28 is a hard coating layer, there is no anti-reflective layer 29, and at least one of the adhesive layers 21, 24, and 26 has light scattering properties. The distance d (μm) between the adhesive layer with light scattering properties and the color filter is 700 μm or less. By setting the distance d between the adhesive layer with light scattering properties and the color filter to be 700 μm or less, even if a light scattering layer is stacked in order to suppress color shift or interference spots caused by the OLED display device 300, patterns will not easily occur. The image is blurry and the visibility is excellent. From the perspective of more efficiently reducing the image blur of the OLED display device caused by the laminated light scattering layer, the distance between the adhesive layer with light scattering properties and the color filter is preferably 600 μm or less. Furthermore, it is preferably 500 μm or less, and it is most preferable that the adhesive layer with light scattering properties is directly connected to the color filter. OLED display devices 400C and 400D of this embodiment are shown in FIGS. 7(a) and (b) respectively. In Figure 7(a), 41C to 48C are layers constituting the optical laminate 40C, 41C is an adhesive layer, 42C is a resin layer, 43C is a hard coat layer, 44C is an adhesive layer, 45C is a glass layer, and 46C is a For the adhesive layer with light scattering properties, 47C is the resin layer and 48C is the hard coat layer. 15C is a color filter disposed on the viewing side of the OLED display panel 400C (the upper side in FIG. 7(a) ). The distance d (μm) between the adhesive layer 46D with light scattering characteristics and the color filter 15C is Below 700 μm. In Figure 7(b), 41D to 48D are layers constituting the optical laminate 40D, 41D is an adhesive layer with light scattering properties, 42D is a resin layer, 43D is a hard coat layer, 44D is an adhesive layer, and 45D is glass. layer, 46D is the adhesive layer, 47D is the resin layer, and 48D is the hard coat layer. 15D is a color filter arranged on the viewing side of the OLED display panel 400D (the upper side in FIG. 7(b) ). The adhesive layer 41D with light scattering properties is directly connected to the color filter 15D. That is, the distance between the adhesive layer 41D with light scattering properties and the color filter 15D is 0 μm. Therefore, the most efficient The color shift or interference spots caused by the OLED display device 400D are effectively suppressed. Furthermore, in the OLED display devices 400C and 400D shown in Figures 7(a) and (b), an anti-reflective layer may also be present on the viewing side of the hard coating layers 48C and 48D.

As another preferred embodiment of the present invention, in Figure 2, 26 is an adhesive layer or adhesive layer, 27 is a resin layer, 28 is an anti-glare layer, and 21 to 25 and 29 are not present. The OLED display device 500A of this embodiment is shown in FIG. 8 . In FIG. 8 , 56A to 58A are layers constituting the optical laminated body 50A, 56A is an adhesive layer or adhesive layer, 57A is a resin layer, and 58A is an anti-glare layer. By providing the optical laminated body 50A with the anti-glare layer 58A, color shift and interference spots caused by the OLED display panel 100 are suppressed, and the OLED display device 500A becomes excellent in visibility. Furthermore, in the OLED display device 500A shown in FIG. 8 , an anti-reflective layer may also be present on the viewing side of the anti-glare layer 58A.

As another preferred embodiment of the present invention, in Figure 2, 24 is an adhesive layer or adhesive layer, 25 is a glass layer, 26 is an adhesive layer or adhesive layer, 27 is a resin layer, and 28 is an anti-glare layer. , 21~23 and 29 do not exist. The OLED display device 500B of this embodiment is shown in FIG. 9 . In Figure 9, 54B to 58B are layers constituting the optical laminate 50B, 54B is an adhesive layer or an adhesive layer, 55B is a glass layer, 56B is an adhesive layer or an adhesive layer, 57B is a resin layer, and 58B is an anti-glare layer. layer. By providing the optical laminated body 50B with the anti-glare layer 58B, color shift and interference spots caused by the OLED display panel 100 are suppressed, and the OLED display device 500B becomes excellent in visibility. Furthermore, in the OLED display device 500B shown in FIG. 9 , an anti-reflective layer may also be present on the viewing side of the anti-glare layer 58B.

As another preferred embodiment of the present invention, in Figure 2, 21 is an adhesive layer, 22 is a resin layer, 23 is a hard coat layer, 24 is an adhesive layer, 25 is a glass layer, 26 is an adhesive layer, 27 is a resin layer, 28 is an anti-glare layer, and there is no anti-reflective layer 29. The OLED display device 500C of this embodiment is shown in FIG. 10 . In Figure 10, 51C to 58C are layers constituting the optical laminate 50C, 51C is an adhesive layer, 52C is a resin layer, 53C is a hard coat layer, 54C is an adhesive layer, 55C is a glass layer, and 56C is an adhesive layer. 57C is the resin layer, and 58C is the anti-glare layer. By providing the optical laminated body 50C with the anti-glare layer 58C, color shift and interference spots caused by the OLED display panel 100 are suppressed, and the OLED display device 500C becomes excellent in visibility. Furthermore, in the OLED display device 500C shown in FIG. 10 , an anti-reflective layer may also be present on the viewing side of the anti-glare layer 58C.

As another preferred embodiment of the present invention, in Figure 2, 26 is an adhesive layer or adhesive layer, 27 is a resin layer, 28 is a hard coating layer, anti-reflective layer 29 is present, and 21 to 25 are not present. The OLED display device 600A of this embodiment is shown in FIG. 11 . In FIG. 11 , 61A to 69A are layers constituting the optical laminated body 60A, 66 is an adhesive layer or adhesive layer, 67A is a resin layer, 68A is a hard coat layer, and 69A is an anti-reflection layer. By providing the optical laminated body 60A with the anti-reflection layer 69A, interference spots caused by the OLED display panel 100 are suppressed, and the OLED display device 600A becomes excellent in visibility. In the OLED display device 600A shown in FIG. 11 , 68A may be an anti-glare layer, and an anti-glare layer may be laminated between the hard coat layer 68A and the anti-reflective layer 69A. In this embodiment, the anti-reflective function is further improved by laminating the anti-glare layer 68A and the anti-reflective layer 69A.

As another preferred embodiment of the present invention, in Figure 2, 24 is an adhesive layer or adhesive layer, 25 is a glass layer, 26 is an adhesive layer or adhesive layer, 27 is a resin layer, and 28 is a hard coat layer. , the anti-reflective layer 29 is present, and 21 to 23 are not present. The OLED display device 600B of this embodiment is shown in FIG. 12 . In Figure 12, 61B to 69B are layers constituting the optical laminate 60B, 64B is an adhesive layer or adhesive layer, 65B is a glass layer, 66B is an adhesive layer or adhesive layer, 67B is a resin layer, and 68B is a hard coat. layer, 69B is the anti-reflective layer. By providing the optical laminated body 60B with the anti-reflection layer 69B, interference spots caused by the OLED display panel 100 are suppressed, and the OLED display device 600B becomes excellent in visibility. In the OLED display device 600B shown in FIG. 12 , 68B may be an anti-glare layer, and an anti-glare layer may be laminated between the hard coat layer 68B and the anti-reflective layer 69B. In this embodiment, the anti-reflective function is further improved by laminating the anti-glare layer 68B and the anti-reflective layer 69B.

As another preferred embodiment of the present invention, in Figure 2, 21 is an adhesive layer, 22 is a resin layer, 23 is a hard coat layer, 24 is an adhesive layer, 25 is a glass layer, 26 is an adhesive layer, 27 is a resin layer, 28 is a hard coat layer, and there is an anti-reflective layer 29. The OLED display device 600C of this embodiment is shown in FIG. 13 . In Figure 13, 61C to 69C are layers constituting the optical laminate 60C, 61C is an adhesive layer, 62C is a resin layer, 63C is a hard coat layer, 64C is an adhesive layer, 65C is a glass layer, and 66C is an adhesive layer. 67C is the resin layer, 68C is the hard coat layer, and 69C is the anti-reflective layer. By providing the optical laminated body 60C with the anti-reflection layer 69C, interference spots caused by the OLED display panel 100 are suppressed, and the OLED display device 600C has excellent visibility. In the OLED display device 600C shown in FIG. 13 , 68C can be an anti-glare layer, and an anti-glare layer can be laminated between the hard coat layer 68C and the anti-reflective layer 69C. In this embodiment, the anti-reflective function is further improved by laminating the anti-glare layer 68C and the anti-reflective layer 69C.

As another preferred embodiment of the present invention, in Figure 2, 21 is an adhesive layer or adhesive layer, 22 is a resin layer, 23 is not present, 24 is an adhesive layer, 25 is a glass layer, and 26 to 29 are not present. . An OLED display device 700A of this embodiment is shown in FIG. 14 . In Figure 14, 71A, 72A, 74A, and 75A are layers constituting the optical laminate 70A, 71A is an adhesive layer or adhesive layer, 72A is a resin layer, and 73A is not present, 74A is an adhesive layer, and 75A is a glass layer. . In FIG. 14 , the resin layer 72A and the glass layer 75A are connected by an adhesive layer 74A. This provides each with excellent impact resistance even when the optical laminated body 70A does not have a polarizing plate. In addition, although the glass layer has excellent impact resistance, it is a material that is easily broken and has low flexibility. By bonding the glass layer and the resin layer with an adhesive layer, the flexibility or bendability is improved, and the OLED display device 700A can be used in a flexible device or a foldable device.

As another preferred embodiment of the present invention, in Figure 2, 21 is an adhesive layer, 22 is a resin layer, 23 is not present, 24 is an adhesive layer, 25 is a glass layer, 26 is an adhesive layer, and 27 is a resin. Layer 28 is a hard coat layer, and there is no anti-reflective layer 29. Or, in Figure 2, 21 is an adhesive layer, 22 is a resin layer, 23 is a hard coat layer, 24 is an adhesive layer, 25 is a glass layer, 26 is an adhesive layer, 27 is a resin layer, and 28 is a hard coat layer. , there is no anti-reflective layer 29. OLED display devices 700B and 700C of this embodiment are shown in FIG. 15(a) and FIG. 15(b) respectively. In Fig. 15(a) , 71B, 72B, 74B to 78B are layers constituting the optical laminate 70B, 71B is an adhesive layer, 72B is a resin layer, 74B is an adhesive layer, 75B is a glass layer, and 76B is an adhesive layer. , 77B is the resin layer, 78B is the hard coat layer. In addition, in Figure 15(b), 71C to 78C are layers constituting the optical laminate 70C, 71C is an adhesive layer, 72C is a resin layer, 73C is a hard coat layer, 74C is an adhesive layer, 75C is a glass layer, and 76C It is the adhesive layer, 77C is the resin layer, and 78C is the hard coat layer. In FIG. 15(a) , the resin layer 72B and the glass layer 75B are bonded by the adhesive layer 74B, or in FIG. 15(b) , the glass layer 75C and the resin layer 77C are bonded by the adhesive layer 76C. , even when the optical laminates 70B and 70C do not have polarizing plates, each of them is provided with excellent impact resistance. In addition, although the glass layer has excellent impact resistance, it is a material that is easily broken and has low flexibility. By bonding the glass layer and the resin layer with an adhesive layer, the flexibility or bendability is improved, and the OLED display devices 700B and 700C can be used in flexible devices or foldable devices. Furthermore, in the OLED display devices 700B and 700C shown in FIGS. 15(a) and (b), an anti-reflective layer may also be present on the viewing side of the hard coating layers 78B and 78C.

As another preferred embodiment of the present invention, in Figure 2, 21 is an adhesive layer, 22 is a resin layer, 23 is a hard coat layer, 24 to 29 are not present, and the resin layer 22 is a transparent polyimide layer. An OLED display device 800A of this embodiment is shown in FIG. 16 . In FIG. 16 , 81A to 83A are layers constituting the optical laminate 80A, 81A is an adhesive layer or adhesive layer, 82A is a transparent polyimide layer, and 83A is a hard coat layer. In FIG. 16 , by providing the optical laminated body 80A with the transparent polyimide layer 82A and the hard coat layer 83A, excellent impact resistance is provided even when the optical laminated body 80A does not have a polarizing plate. Moreover, in this embodiment, the optical laminated body 80A does not have a glass layer. Although the glass layer is a material that exhibits high hardness and excellent impact resistance, it has poor operability and is not easy to use on large displays used in PCs and tablets. By laminating a transparent polyimide layer and a hard coat layer, it can achieve a high hardness equivalent to that of a glass layer and has excellent operability, so it can also be applied to large displays used in PCs and tablets.

As another preferred embodiment of the present invention, in Figure 2, 21 is an adhesive layer, 22 is a resin layer, 23 is a hard coat layer, 24 is an adhesive layer, 25 and 26 are not present, and 27 is a resin layer. 28 is a hard coat layer, there is no anti-reflective layer 29, and either or both of the resin layers 22 and 27 are transparent polyimide layers. The OLED display device 800B of this embodiment is shown in FIG. 17 . In Figure 17, 81B to 84B, 87B, and 88B are layers constituting the optical laminate 80B. 81B is an adhesive layer, 82B is a transparent polyimide layer, 83B is a hard coat layer, 84B is an adhesive layer, and 87B is a resin. layer, 88B is a hard coating. In FIG. 17 , by providing the optical laminated body 80B with the transparent polyimide layer 82B and the hard coat layer 83B, excellent impact resistance is provided even when the optical laminated body 80B does not have a polarizing plate. Moreover, in this embodiment, the optical laminated body 80B does not have a glass layer. Although the glass layer is a material that exhibits high hardness and excellent impact resistance, its operability is poor and it is not easy to be used in large displays such as PCs and tablets. By laminating a transparent polyimide layer and a hard coat layer, it is possible to achieve a hardness as high as that of a glass layer and has excellent operability, so it can also be applied to large displays used in PCs and tablets.

In the embodiment shown in FIGS. 16 and 17 , it is preferable to form an intermediate layer between the transparent polyimide layer 82A and the hard coat layer 83A, and between the transparent polyimide layer 82B and the hard coat layer 83B. (Compatible layer) (illustration omitted). By forming an intermediate layer (compatibility layer) between the transparent polyimide layers 82A, 82B and the hard coat layers 83A, 83B, the transparent polyimide layers 82A, 82B and the hard coat layers 83A, 83B are closely connected. sexual enhancement. In this case, the shear failure strength between the transparent polyimide layers 82A and 82B and the hard coat layers 83A and 83B is preferably 20 MPa or more. [Example]

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

Example 1 ＜OLED display device＞ The optical film laminated on the viewing side of the 4K OLED display (Model: EPS269Q015A) manufactured by JOLED Co., Ltd. was peeled off to prepare the OLED display device.

<Formation of hard coat> 100 parts by weight of ultraviolet curable polyfunctional acrylic resin composition (trade name "Z-850-50H-D", manufactured by Aica Kogyo Co., Ltd., solid content) Ingredient concentration: 44% by weight), 4 parts by weight of photopolymerization initiator (trade name "Omnirad 2959", manufactured by IGM Resins Italia Srl), and leveling agent (trade name "LE-303", Kyoeisha Chemical ( (stock)) 0.05 parts by weight were mixed to obtain a mixed liquid. Next, methyl isobutyl ketone was added to the obtained mixed liquid to obtain a hard coat layer forming composition having a solid content concentration of 40% by weight. Next, the above-mentioned hard coat layer forming composition was applied to one side of a PET film (trade name "50U48", manufactured by Toray Co., Ltd., thickness: 50 μm) as a transparent film base material to form a coating film. Next, the coating film was dried by heating it at a temperature of 80° C. for 60 seconds, and then cured by ultraviolet irradiation. When irradiating ultraviolet light, use a high-pressure mercury lamp as the light source, use ultraviolet light with a wavelength of 365 nm, and set the cumulative light amount to 300 mJ/cm ² . Thereby, a hard coating layer with a thickness of 3 μm was formed on the PET film.

＜Surface treatment of hard coating＞ Then, using a roll-to-roll plasma treatment device, in a vacuum atmosphere of 1.0 Pa, plasma treatment was performed on the surface of the hard coat layer while transporting the PET film on which the hard coat layer was formed. During plasma treatment, use argon as an inert gas and set the discharge power to 150 W. Thereby, an optical film having a PET film and a plasma-treated hard coating layer is obtained.

<Formation of Primer Coat> Next, the heated optical film was introduced into a roll-to-roll sputtering film-forming device, and the pressure in the film-forming chamber was reduced to 1×10 ^-4 Pa. Then, while transporting the optical film, argon gas and oxygen gas were introduced at a volume ratio of 100:10, the surface temperature of the film forming roller was set to -8°C, and an ITO layer with a thickness of 1.5 nm was formed on the hard coat layer by sputtering. (base coat). When forming the undercoat layer, an ITO target containing indium oxide and tin oxide as target materials in a weight ratio of 90:10 is used. In addition, when the film is formed by sputtering, the power supply is set to the MFAC power supply, the discharge power is set to 2.5 kW, and the pressure in the film forming chamber is set to 0.2 Pa.

<Formation of anti-reflective layer> Following the formation of the undercoat layer, a roll-to-roll sputtering film-forming device is used to transport the optical film after the undercoat layer is formed, and the sputtering method is used to sequentially form the optical film on the undercoat layer. The first layer of the film: ₅ layers of Nb ₂ O with a thickness of 12 nm (refractive index: 2.32), the second layer: ₂ layers of SiO with a thickness of 29 nm (refractive index: 1.46), the third layer: Nb ₂ O with a thickness of 107 nm Layer ₅ , and layer 4: SiO ₂ layer with a thickness of 81 nm. Thereby, an anti-reflective layer composed of four layers (a four-layer structure including a first layer, a second layer, a third layer, and a fourth layer) is formed on the base coat layer. When forming each layer from layer 1 to layer 4, set the surface temperature of the film forming roller to -8°C, set the power supply to MFAC power supply, and set the pressure in the film forming chamber to 0.7 Pa. In addition, when forming the first layer, an Nb target was used, argon gas and oxygen gas were introduced at a volume ratio of 100:5, and the discharge power was set to 10.5 kW. When forming the second layer, a Si target was used, argon and oxygen were introduced at a volume ratio of 100:30, and the discharge power was set to 14 kW. When forming the third layer, an Nb target was used, argon and oxygen were introduced at a volume ratio of 100:13, and the discharge power was set to 22 kW. When forming the fourth layer, a Si target was used, argon and oxygen were introduced at a volume ratio of 100:30, and the discharge power was set to 12 kW.

＜Formation of antifouling layer＞ An alkoxysilane compound containing a perfluoropolyether skeleton (trade name "SHIN-ETSU SUBELYN KY1903-1", manufactured by Shin-Etsu Chemical Industry Co., Ltd.) that has been dried and solidified is used as a vapor deposition source. The heating temperature was set to 260°C, and an antifouling layer with a thickness of 12 nm was formed on the anti-reflective layer using vacuum evaporation. Thereby, an optical laminate including a PET film, a hard coat layer, a primer layer, an antireflection layer, and an antifouling layer is obtained.

＜Production of OLED display device with optical laminate＞ The optical laminate is laminated on the above-mentioned OLED display device via an acrylic adhesive so that the antifouling layer of the above-mentioned optical laminate becomes the viewing side, thereby producing an OLED display device with an optical laminate.

Examples 2 to 4 Except for changing the thickness of the first to fourth layers in the formation step of the anti-reflection layer to the conditions shown in Table 1, the same production method as in Example 1 was used to produce the OLED displays with optical laminates of Examples 2 to 4. device.

Comparative example 1 The OLED with optical laminate of Comparative Example 1 was produced using the same production method as Example 1, except that the surface treatment of the hard coat layer, the formation of the undercoat layer, the formation of the anti-reflection layer, and the formation of the antifouling layer were not performed. display device.

＜Evaluation＞ The following evaluations were performed on the OLED display devices with optical laminates produced in Examples and Comparative Examples. The results are shown in Table 1.

(1)Rf1, Rf2, Rp1, Rp2 A spectrophotometer manufactured by Hitachi High-Technology Co., Ltd. was used to measure the reflectance of the optical laminate at each wavelength from 380 to 780 nm. Next, the optical film laminated on the viewing side of the 4K OLED display (model: EPS269Q015A) manufactured by JOLED Co., Ltd. was peeled off, and the peeling of the OLED display device was measured using a spectrophotometer "CM-2600d" manufactured by Konica Minolta Co., Ltd. The reflectivity of the surface of the optical film at each wavelength from 380 to 780 nm is used to calculate the first peak wavelength WL1 (nm) and the second peak wavelength WL2 (nm). The first peak value is the maximum value at a wavelength of 380~455 nm, and the second peak value is a maximum value at a wavelength of 460~530 nm. Calculate the reflectance of the above-mentioned OLED display at the first peak wavelength WL1 (nm) and the second peak wavelength WL2 (nm) as Rp1 and Rp2 respectively, and calculate the first peak wavelength WL1 (nm) and the second peak wavelength WL2 (nm). ) are represented by Rf1 and Rf2 respectively. Furthermore, the reflectance of the optical laminates in Examples 1 to 4 is equivalent to the reflectance of the antireflection layer.

(2) Interference spots The OLED display device with an optical laminated body obtained in the Examples and Comparative Examples was placed in an unlit state, and a three-wavelength fluorescent lamp was lit at a distance of 30 cm from the OLED display device with an optical laminated body, and the optical laminated body was visually observed. Interference spots on the surface of a solid OLED display device are judged according to the following standards. ◎; The interference spot cannot be recognized at all 〇; The interference spot is almost invisible ×; interference spots can be clearly seen

[Table 1] (Table 1) Thickness of anti-reflective layer [nm] [Rf1/Rp1] [Rf2/Rp2] [Rf1/Rp1]+[Rf2/Rp2] interference spots Tier 1 Tier 2 Level 3 Level 4 Example 1 12 29 107 81 0.063 0.004 0.067 ◎ Example 2 12 29 90 81 0.160 0.025 0.185 〇 Example 3 12 29 70 81 0.246 0.087 0.333 〇 Example 4 12 29 50 81 0.184 0.113 0.297 〇 Comparative example 1 - - - - 0.313 0.367 0.680 ×

Modifications of the present invention are described below. [Note 1] An optical laminate for an OLED display device, which is an optical laminate used in an OLED display device in which only optical elements with a polarization degree of 95% or less are laminated on the viewing side of the OLED element, and The above-mentioned optical element has an anti-reflection layer at least on the viewing side. [Additional Note 2] The optical laminated body for an OLED display device as described in Supplementary Note 1, wherein the reflectance spectrum of the OLED display device in a state where the optical laminated body for an OLED display device is not laminated has a wavelength of 380 to 455 nm. When the maximum value below is Rp1 and the reflectance of the anti-reflection layer at the wavelength at Rp1 is Rf1, [Rf1/Rp1] is 0.3 or less. [Additional Note 3] The optical laminated body for an OLED display device as described in Supplementary Note 1 or 2, wherein the reflectance spectrum of the OLED display device in a state in which the optical laminated body for an OLED display device is not laminated has a wavelength of 460 to When the maximum value at 530 nm is Rp2 and the reflectance of the anti-reflection layer at the wavelength of Rp2 is Rf2, [Rf2/Rp2] is 0.12 or less. [Supplementary Note 4] The optical laminated body for an OLED display device according to any one of Supplementary Notes 1 to 3, wherein in the reflectance spectrum of the above-mentioned OLED display device in a state where the optical laminated body for an OLED display device is not laminated, when Let the maximum value at the wavelength of 380~455 nm be Rp1, let the reflectance of the anti-reflection layer at the wavelength of Rp1 be Rf1, let the maximum value at the wavelength of 460~530 nm be Rp2, let the above Rp2 When the reflectance of the above anti-reflection layer at the wavelength of time is set to Rf2, The total of [Rf1/Rp1] and [Rf2/Rp2] is 0.42 or less. [Appendix 5] The optical laminate for an OLED display device according to any one of Appendices 1 to 4, wherein the antireflection layer has a water contact angle of 100° or more. [Appendix 6] The optical laminate for an OLED display device according to any one of Appendices 1 to 5, wherein the anti-reflection layer has a water contact angle of 90° or more after an eraser test. [Appendix 7] The optical laminate for an OLED display device according to any one of Appendices 1 to 6, wherein the antireflection layer contains an inorganic substance. [Appendix 8] The optical laminate for an OLED display device according to any one of Appendices 1 to 7, wherein the antireflection layer is provided with a hard coat layer, a base material layer, and an adhesive on the side opposite to the viewing side. layer. [Supplement 9] The optical laminate for an OLED display device as described in Appendix 8, wherein the adhesive layer has a haze value of 20 to 90%. [Supplement 10] The optical laminate for an OLED display device according to Appendix 8 or 9, wherein the thickness of the hard coat layer is 2 to 10 μm.

10R: Red OLED layer 10G: Green OLED layer 10B: Blue OLED layer 11a: Transparent electrode (cathode) 11b: Back electrode (anode) 12B:Blue OLED component 12R: red OLED component 12G: Green OLED components 13:Substrate 14:TFT layer 15: Color filter 15A: Color filter 15B: Color filter 15C: Color filter 15D: Color filter 15R: red coloring layer 15G: green coloring layer 15B: Blue coloring layer 16: Black matrix layer 17:Jointing layer 20: Optical laminated body 21: Adhesive layer or adhesive layer 22: Resin layer, glass layer or impact absorption layer 23: Hard coating or anti-glare layer 24: Adhesive layer or adhesive layer 25: Resin layer, glass layer or impact absorption layer 26: Adhesive layer or adhesive layer 27: Resin layer, glass layer or impact absorption layer 28: Hard coating or anti-glare layer 29:Anti-reflective layer 30A: Optical laminated body 30B: Optical laminated body 31B: Adhesive layer 32B: Resin layer 33B:Hard coating 34A: Adhesive layer or adhesive layer 34B: Adhesive layer 35A:Glass layer 35B:Glass layer 36A: Adhesive layer with light scattering properties 36B: Adhesive layer with light scattering properties 37A: Resin layer 37B: Resin layer 38A:Hard coating 38B:Hard coating 40A: Optical laminated body 40B: Optical laminated body 40C: Optical laminated body 40D: Optical laminated body 41C: Adhesive layer 41D: Adhesive layer with light scattering properties 42C: Resin layer 42D: Resin layer 43C: Hard coating 43D: Hard coating 44B: Adhesive layer with light scattering properties 44C: Adhesive layer 44D: Adhesive layer 45B:Glass layer 45C: glass layer 45D:Glass layer 46A: Adhesive layer with light scattering properties 46B: Adhesive layer 46C: Adhesive layer with light scattering properties 46D: Adhesive layer 47A:Resin layer 47B: Resin layer 47C: Resin layer 47D: Resin layer 48A:Hard coating 48B:Hard coating 48C: Hard coating 48D:hard coating 50A: Optical laminated body 50B: Optical laminated body 50C: Optical laminated body 51C: Adhesive layer 52C: Resin layer 53C: Hard coating 54B: Adhesive layer or adhesive layer 54C: Adhesive layer 55B:Glass layer 55C:Glass layer 56A: Adhesive layer or adhesive layer 56B: Adhesive layer or adhesive layer 56C: Adhesive layer 57A: Resin layer 57B: Resin layer 57C: Resin layer 58A: Anti-glare layer 58B:Anti-glare layer 58C: Anti-glare layer 60A: Optical laminated body 60B: Optical laminated body 60C: Optical laminated body 61C: Adhesive layer 62C: Resin layer 63C: Hard coating 64B: Adhesive layer or adhesive layer 64C: Adhesive layer 65B:Glass layer 65C: Glass layer 66A: Adhesive layer or adhesive layer 66B: Adhesive layer or adhesive layer 66C: Adhesive layer 67A: Resin layer 67B: Resin layer 67C: Resin layer 68A:Hard coating 68B:Hard coating 68C: Hard coating 69A:Anti-reflective layer 69B:Anti-reflective layer 69C: Anti-reflective layer 70A: Optical laminated body 70B: Optical laminated body 70C: Optical laminated body 71A: Adhesive layer 71B: Adhesive layer 71C: Adhesive layer 72A: Resin layer 72B: Resin layer 72C: Resin layer 73C: Hard coating 74A: Adhesive layer 74B: Adhesive layer 74C: Adhesive layer 75A:Glass layer 75B:Glass layer 75C: Glass layer 76B: Adhesive layer 76C: Adhesive layer 77B: Resin layer 77C: Resin layer 78B:Hard coating 78C: Resin layer 80A: Optical laminated body 80B: Optical laminated body 81A: Adhesive layer 81B: Adhesive layer 82A: Transparent polyimide layer 82B: Transparent polyimide layer 83A:Hard coating 83B:Hard coating 84B: Adhesive layer 87B: Resin layer 88B:Hard coating 100:OLED display panel 200:OLED display device 300A:OLED display device 300B:OLED display device 400A:OLED display device 400B:OLED display device 400C:OLED display device 400D:OLED display device 500A:OLED display device 500B:OLED display device 500C:OLED display device 600A:OLED display device 600B:OLED display device 600C:OLED display device 700A:OLED display device 700B:OLED display device 700C:OLED display device 800A:OLED display device 800B:OLED display device C1: 1st light path (direct light) C2: 2nd optical path (reflected light) G: Reflected light W: external light

FIG. 1 is a schematic cross-sectional view showing an embodiment of the OLED display panel of the present invention. FIG. 2 is a schematic cross-sectional view showing one embodiment of an OLED display device in which the optical laminate of the present invention is laminated. FIG. 3 is a schematic cross-sectional view showing one embodiment of an OLED display device in which the optical laminate of the present invention is laminated. FIG. 4 is a schematic cross-sectional view showing one embodiment of an OLED display device in which the optical laminate of the present invention is laminated. FIG. 5 is a schematic cross-sectional view showing one embodiment of an OLED display device in which the optical laminate of the present invention is laminated. FIG. 6 is a schematic cross-sectional view showing one embodiment of an OLED display device in which the optical laminate of the present invention is laminated. 7(a) and (b) are schematic cross-sectional views showing one embodiment of an OLED display device in which the optical laminated body of the present invention is laminated. FIG. 8 is a schematic cross-sectional view showing one embodiment of an OLED display device in which the optical laminate of the present invention is laminated. FIG. 9 is a schematic cross-sectional view showing one embodiment of an OLED display device in which the optical laminate of the present invention is laminated. FIG. 10 is a schematic cross-sectional view showing one embodiment of an OLED display device in which the optical laminate of the present invention is laminated. FIG. 11 is a schematic cross-sectional view showing one embodiment of an OLED display device in which the optical laminate of the present invention is laminated. FIG. 12 is a schematic cross-sectional view showing one embodiment of an OLED display device in which the optical laminate of the present invention is laminated. FIG. 13 is a schematic cross-sectional view showing one embodiment of an OLED display device in which the optical laminate of the present invention is laminated. FIG. 14 is a schematic cross-sectional view showing one embodiment of an OLED display device in which the optical laminate of the present invention is laminated. 15(a) and (b) are schematic cross-sectional views showing one embodiment of an OLED display device in which the optical laminated body of the present invention is laminated. FIG. 16 is a schematic cross-sectional view showing one embodiment of an OLED display device in which the optical laminate of the present invention is laminated. FIG. 17 is a schematic cross-sectional view showing one embodiment of an OLED display device in which the optical laminate of the present invention is laminated.

60A: Optical laminated body

66A: Adhesive layer or adhesive layer

67A: Resin layer

68A:Hard coating

69A:Anti-reflective layer

100:OLED display panel

600A:OLED display device

Claims (10)

An optical laminate for an OLED display device, which is an optical laminate used in an OLED display device in which only optical elements with a polarization degree of 95% or less are laminated on the viewing side of the OLED element, and The above-mentioned optical element has an anti-reflection layer at least on the viewing side. The optical laminated body for an OLED display device according to Claim 1, wherein in the reflectance spectrum of the OLED display device in a state where the optical laminated body for an OLED display device is not laminated, the maximum value at a wavelength of 380 to 455 nm is set is Rp1, and when the reflectance of the anti-reflection layer at the wavelength at Rp1 is Rf1, [Rf1/Rp1] is 0.3 or less. The optical laminated body for an OLED display device according to Claim 2, wherein in the reflectance spectrum of the OLED display device in a state where the optical laminated body for an OLED display device is not laminated, the maximum value at a wavelength of 460 to 530 nm is set is Rp2, and when the reflectivity of the anti-reflection layer at the wavelength at Rp2 is Rf2, [Rf2/Rp2] is 0.12 or less. The optical laminated body for an OLED display device according to Claim 3, wherein the total of the above-mentioned [Rf1/Rp1] and the above-mentioned [Rf2/Rp2] is 0.42 or less. The optical laminate for an OLED display device according to any one of claims 1 to 4, wherein the water contact angle of the anti-reflection layer is 100° or more. The optical laminate for an OLED display device according to any one of claims 1 to 4, wherein the water contact angle of the anti-reflection layer after the eraser test is 90° or more. The optical laminate for an OLED display device according to any one of claims 1 to 4, wherein the anti-reflection layer contains an inorganic substance. The optical laminate for an OLED display device according to any one of claims 1 to 4, wherein the anti-reflection layer is provided with a hard coat layer, a base material layer, and an adhesive layer on the side opposite to the viewing side. As claimed in Claim 8, the optical laminate for an OLED display device, wherein the haze value of the adhesive layer is 20 to 90%. The optical laminated body for an OLED display device according to claim 8, wherein the thickness of the hard coat layer is 2 to 10 μm.