Laminate, optical member, and optical device

Abstract

Provided is a laminate having both adhesive force or adhesive strength and difficulty in penetration of an adhesive agent or an adhesive into voids of a void layer. The laminate (10) includes a void layer (11) and an adhesive layer (12), the adhesive layer (12) is directly laminated on one or both surfaces of the void layer (11), the adhesive layer (12) is formed from an adhesive agent containing a (meth) acrylic polymer and a monomeric silane coupling agent, and the content of the (meth) acrylic polymer in the (meth) acrylic polymer is 100 parts by mass per 100 parts by mass of the (meth) acrylic polymer, and the content of the monomeric silane coupling agent in the (meth) acrylic polymer is 100 parts by mass per 100 parts by mass of the (meth) acrylic polymer per 100 parts by mass of the (meth) acrylic polymer per 100 parts by mass of the (meth) acrylic polymer. The content of the haplotype silane coupling agent is 5.0 parts by mass or less.

Description

Technical Field

[0001] This disclosure relates to laminates, optical components, and optical devices. Background Technology

[0002] In optical devices, for example, low-refractive-index air layers are utilized as total internal reflection layers. Specifically, for example, in liquid crystal devices, optical film components (e.g., light guide plates and reflectors) are stacked with air layers between them. However, if the components are separated by air layers, problems such as component deflection may occur, especially when the components are large. Furthermore, due to the trend towards thinner devices, integration of components is desired. Therefore, integration of components without air layers has been carried out using adhesives (e.g., Patent Document 1). However, without air layers to provide total internal reflection, there is a risk of reduced optical properties such as light leakage.

[0003] Therefore, a solution has been proposed to use a low-refractive-index layer instead of an air layer. For example, Patent Document 2 describes a structure in which a layer with a lower refractive index than the light guide plate is inserted between the light guide plate and the reflector plate. As a low-refractive-index layer, for example, a void layer with gaps can be used to make the refractive index as close as possible to that of air.

[0004] Furthermore, in order to introduce the void layer into the device, an integral configuration with the adhesive layer has been proposed (Patent Document 3).

[0005] Existing technical documents

[0006] Patent documents

[0007] Patent Document 1: Japanese Patent Application Publication No. 2012-156082

[0008] Patent Document 2: Japanese Patent Application Publication No. 10-62626

[0009] Patent Document 3: Japanese Patent Application Publication No. 2014-46518 Summary of the Invention

[0010] The problem that the invention aims to solve

[0011] For void layers, they can be used, for example, by being laminated with other layers via an adhesive layer. However, if the void layer is laminated with the adhesive layer, there is a risk that the adhesive or bonding agent constituting the adhesive layer may penetrate into the voids of the void layer and fill them, thereby reducing the porosity of the void layer and increasing its refractive index. The higher the porosity of the void layer, the easier it is for the adhesive or bonding agent to penetrate. Furthermore, in high-temperature environments, the molecular motion of the adhesive or bonding agent (reduced elastic modulus) makes it easier for the adhesive or bonding agent to penetrate into the voids. In high-humidity environments, the water absorption of the adhesive or bonding agent makes it easier for it to penetrate into the voids.

[0012] To suppress or prevent the penetration of the adhesive or bonding agent into the aforementioned voids, a material with a high modulus of elasticity (hardness) should be used as the adhesive or bonding agent. However, if the adhesive or bonding agent has a high modulus of elasticity (hardness), there is a risk of reduced adhesive strength or bonding force. Conversely, if the adhesive or bonding agent has a low modulus of elasticity (softness), although high adhesive strength or bonding force is easily obtained, there is a risk that the adhesive or bonding agent will easily penetrate into the aforementioned voids.

[0013] Therefore, the purpose of this disclosure is to provide laminates, optical components, and optical devices that take into account both adhesive strength or bonding strength and the difficulty of impregnating adhesives or binders into the voids of the void layer.

[0014] Problem Solving Methods

[0015] To achieve the above objectives, the laminate of this disclosure includes a void layer and an adhesive layer.

[0016] The aforementioned adhesive layer is directly laminated onto one or both sides of the aforementioned void layer.

[0017] The aforementioned adhesive layer is formed from an adhesive comprising a (meth)acrylic polymer and a monomeric silane coupling agent.

[0018] The content of the monomeric silane coupling agent is 5.0 parts by mass or less, relative to 100 parts by mass of the above (meth)acrylic polymer.

[0019] The optical components disclosed herein comprise the laminates described above.

[0020] The optical device disclosed herein includes the optical components described above.

[0021] The effects of the invention

[0022] According to this disclosure, laminates, optical components, and optical devices can be provided that take into account both adhesive strength or bonding strength and the difficulty of impregnating adhesives or binders into the voids of the void layer. Attached Figure Description

[0023] Figure 1 (a) and (b) are cross-sectional views illustrating the structure of the laminates disclosed herein.

[0024] Figure 2 (a) and (b) are cross-sectional views illustrating another example of the structure of the laminate of this disclosure.

[0025] Figure 3 (a) and (b) are cross-sectional views showing yet another example of the structure of the laminate of this disclosure.

[0026] Symbol Explanation

[0027] 10, 10a, 10b, 10c, 10d, 10e laminates

[0028] 11. Porous layer

[0029] 12 Adhesive Layer

[0030] 13 Intermediate Layer

[0031] 14 Substrate Detailed Implementation

[0032] The following examples will illustrate this disclosure in more detail. However, this disclosure is not limited by the following description.

[0033] In the laminates disclosed herein, for example, the weight-average molecular weight (Mw) of the aforementioned (meth)acrylic acid polymers can be from 1.5 million to 4 million.

[0034] In the laminates disclosed herein, for example, the adhesive layer is formed of an adhesive comprising the aforementioned (meth)acrylic polymer and a crosslinking agent, wherein the gel fraction of the adhesive may exceed 85%.

[0035] In the laminates disclosed herein, for example, the aforementioned (meth)acrylic acid polymer may contain 1 to 30% by mass of a nitrogen-containing monomer as a monomer unit. It should be noted that, unless otherwise specified, "mass%" and "weight%" are interchangeable in this disclosure, as are "parts by mass" and "parts by weight".

[0036] In the laminates disclosed herein, for example, the nitrogen-containing monomer can be a heterocyclic acrylic acid monomer.

[0037] In the laminates disclosed herein, for example, the aforementioned (meth)acrylic acid polymer may contain 0.5 to 20% by mass of acrylic acid as a monomer unit.

[0038] In the laminates disclosed herein, for example, the aforementioned void layer may not contain organofluorine compounds. By ensuring that the void layer does not contain organofluorine compounds, it is possible to provide laminates, optical components, and optical devices that include environmentally friendly void layers. It should be noted that the aforementioned void layer "does not contain" organofluorine compounds means that even if the void layer is analyzed, organofluorine compounds cannot be detected, and the presence of organofluorine compounds in the void layer cannot be confirmed.

[0039] In the laminate of this disclosure, for example, before and after a heat durability test at a temperature of 65°C and a relative humidity of 95% for 500 hours, the change in the refractive index of the aforementioned void layer can satisfy the following mathematical formula (1).

[0040] |n-n0| < 0.04 (1)

[0041] In the above mathematical formula (1),

[0042] n is the refractive index of the aforementioned porous layer after the above-mentioned heat durability test.

[0043] n0 is the refractive index of the aforementioned void layer before the aforementioned heat durability test.

[0044] In the laminate of this disclosure, for example, there may be an intermediate layer between the void layer and the adhesive layer, the intermediate layer being a layer formed by the void layer and the adhesive layer being integrated.

[0045] In the laminates disclosed herein, for example, the thickness of the intermediate layer can be 10 to 100 nm.

[0046] In this disclosure, "adhesive layer" refers to a layer formed by at least one of an adhesive and a bonding agent. Unless otherwise specified, "adhesive layer" in this disclosure can be an "adhesive layer" formed by an adhesive, an "adhesive layer" formed by a bonding agent, or a layer containing both an adhesive and a bonding agent. Furthermore, in this disclosure, adhesives and bonding agents are sometimes collectively referred to as "adhesive bonding agents." Generally, agents with relatively weak adhesion or bonding strength (e.g., agents that enable re-peeling of the bonded objects) are sometimes referred to as "adhesives," while agents with relatively strong adhesion or bonding strength (e.g., agents that cannot or are extremely difficult to re-peel the bonded objects) are sometimes referred to as "bonding agents." In this disclosure, there is no clear distinction between adhesives and bonding agents. Additionally, in this disclosure, there is no clear distinction between "adhesive strength" and "bonding force."

[0047] In addition, in this disclosure, "on top" or "on surface" can mean a state of direct contact on top or on surface, or a state of being separated by other layers, etc.

[0048] In the laminates disclosed herein, for example, the aforementioned (meth)acrylic polymer can be a (meth)acrylic polymer with a weight average molecular weight of 2 million to 3.5 million obtained by polymerizing heterocyclic acrylic monomers (heterocyclic acrylates) as monomer components at 3 to 20% by mass, (meth)acrylic acid at 0.5 to 5% by mass, (meth)acrylic acid hydroxyalkyl ester at 0.05 to 2% by mass, and (meth)acrylic acid alkyl ester at 83 to 96.45% by mass.

[0049] In the laminates disclosed herein, for example, in the aforementioned adhesive layer, the nitrogen-containing monomer may be a monomer having one or two reactive double bonds in one molecule. The monomer having one or two reactive double bonds in one molecule may, for example, be a heterocyclic acrylic acid monomer (a heterocyclic acrylate).

[0050] In the laminate of this disclosure, the gel fraction of the adhesive forming the adhesive layer can be, for example, 85% by mass or more, or more than 85% by mass, for example, 90% by mass or more, 91% by mass or more, or 93% by mass or more, or for example, 100% by mass or less, 99% by mass or less, or 98% by mass or less.

[0051] In the laminate of this disclosure, the initial refractive index (hereinafter sometimes referred to as "initial refractive index") of the aforementioned void layer before the aforementioned heat durability test may, for example, be 1.30 or less or less than 1.30, or for example, 1.25 or less, less than 1.25, 1.20 or less, or less than 1.20. The lower limit of the aforementioned initial refractive index may, for example, be 1.05 or more, 1.06 or more, 1.07 or more, or 1.08 or more.

[0052] In the laminate of this disclosure, the refractive index of the aforementioned void layer after the heat durability test can be, for example, 1.50 or less or less than 1.50, such as 1.40 or less, less than 1.40, 1.30 or less, or less than 1.30. The lower limit of the refractive index of the aforementioned void layer after the heat durability test can be, for example, 1.05 or more, 1.06 or more, 1.07 or more, or 1.08 or more.

[0053] In the laminate of this disclosure, before and after a heat durability test at a temperature of 65°C and a relative humidity of 95% for 500 hours, the change in the refractive index of the void layer represented by |n-n0| in the above mathematical formula (1) can be less than 0.04, for example, as shown in the above mathematical formula (1). The change in the refractive index of the void layer represented by |n-n0| can be, for example, less than 0.03, less than 0.03, less than 0.02, or less than 0.02. The lower limit of the change in the refractive index of the void layer represented by |n-n0| is not particularly limited, for example, it can be greater than 0, or it can be a value greater than 0.

[0054] In the laminate of this disclosure, before and after a heat durability test at 65°C and 95% relative humidity for 500 hours, the increase rate (%) of the refractive index of the aforementioned void layer, expressed as (|n-n0| / n0)×100, can be, for example, less than 3.0%. The increase rate of the refractive index of the aforementioned void layer, expressed as (|n-n0| / n0)×100, can be, for example, less than 2.0%, less than 2.0%, less than 1.0%, or less than 1.0%. The lower limit of the increase rate of the refractive index of the aforementioned void layer, expressed as (|n-n0| / n0)×100, is not particularly limited; for example, it can be greater than or equal to 0, or it can be a value greater than 0. It should be noted that, similar to the above mathematical formula (1), n0 is the refractive index (initial refractive index) of the aforementioned void layer before the heat durability test, and similarly to the above mathematical formula (1), n ​​is the refractive index of the aforementioned void layer after the heat durability test.

[0055] In the laminates disclosed herein, for example, the porosity of the aforementioned void layer can be 35% or more by volume.

[0056] In the laminates disclosed herein, for example, the aforementioned void layer can be a porous body formed by the chemical bonding of microporous particles with each other.

[0057] In the laminate of this disclosure, the adhesive layer may be, for example, a layer formed by a method comprising the following steps: an adhesive preparation step of preparing an adhesive coating liquid comprising a (meth)acrylic polymer and a monomeric silane coupling agent; an adhesive coating process of applying the adhesive coating liquid to a substrate; and a heat drying process of heating and drying the substrate coated with the adhesive coating liquid. In the laminate of this disclosure, for example, the adhesive layer may be formed from an adhesive coating liquid having a specific composition and integrated with the void layer. Therefore, particularly in long-term heat durability tests, significant penetration of the adhesive layer into the void layer can be suppressed. The adhesive coating liquid may further comprise a crosslinking agent, or other components as described later.

[0058] The reasons (mechanisms) for balancing adhesive strength and the difficulty of adhesive penetration into the voids in the laminates disclosed herein can be considered as follows. For example, by using a specific adhesive to form an adhesive layer, both adhesive strength and the difficulty of adhesive penetration into the voids can be balanced. More specifically, for example, by using a specific (meth)acrylic polymer as described above and using a crosslinking agent as needed to form an adhesive layer, an intermediate layer can be formed by integrating a portion of the void layer with a portion of the adhesive layer. Furthermore, by using the specific (meth)acrylic polymer as described above, the intermediate layer will not over-expand even under conditions such as the aforementioned heat durability test. Moreover, the intermediate layer acts as a barrier, suppressing the reduction in porosity caused by the adhesive filling the voids in the void layer. Even when the molecular motion of the adhesive increases under heating, if the elastic modulus of the adhesive is high, the intermediate layer formed by the adhesive and the high-porosity layer easily becomes a strong and dense barrier, suppressing the penetration of the adhesive into the high-porosity layer. However, it should be noted that these mechanisms are merely examples and do not constitute any limitation on this disclosure.

[0059] Furthermore, the adhesive coating liquid contains, for example, monomers having one or two reactive double bonds per molecule, which can undergo a crosslinking reaction with crosslinking agents such as isocyanate crosslinking agents and epoxy crosslinking agents by heating. It can be considered that during this crosslinking reaction, since the monomers having one or two reactive double bonds per molecule coexist with the organic peroxide acting as a dehydrogenation initiator, the semi-polymer components with a molecular weight of 10,000 or less contained in the adhesive coating liquid are also crosslinked at a high density, thereby suppressing the penetration of components from the adhesive coating liquid into the void layer at a higher level. That is, it can be considered that the semi-polymer components with a molecular weight of 10,000 or less, due to their small molecular size, easily penetrate into the voids of the void layer, but through the crosslinking reaction, the molecular size increases, thereby suppressing penetration into the voids of the void layer. It can be further inferred that by allowing monomers with one or two reactive double bonds per molecule to coexist during the aforementioned crosslinking reaction, grafting reactions with the (meth)acrylic acid polymer backbone and high-density crosslinking starting from the grafted chain can be achieved, thereby reducing the amount of semi-polymers that may become sol components. However, it should be noted that these mechanisms are merely examples and do not constitute any limitation on this disclosure.

[0060] In order to enable the main chains to crosslink efficiently with each other in the grafting reaction, the adhesive coating liquid used to form the adhesive layer in the laminate of the present disclosure preferably has a small number of functional groups (the number of reactive double bonds in one molecule). For example, as described above, the number of reactive double bonds is preferably one or two in one molecule.

[0061] It should be noted that, when manufacturing (meth)acrylic polymers, even when mixing monomers having one or two reactive double bonds, it is difficult to reduce the amount of the semi-polymer (small molecular weight, easily penetrating into the voids of the void layer) as described above. However, according to this disclosure, by using an adhesive coating liquid obtained by subsequently mixing monomers having one or two reactive double bonds into the (meth)acrylic polymer and subjecting it to a crosslinking reaction, a grafting reaction, as described above, can occur, thereby reducing the amount of the semi-polymer.

[0062] In this disclosure, "(meth)acryloyl" means at least one of acryloyl and methacryloyl. For example, "(meth)acrylic acid" means at least one of acrylic acid and methacrylic acid. "(meth)acrylate" means at least one of acrylate and methacrylate. "(meth)acrylate" means at least one of methyl acrylate and methyl methacrylate.

[0063] In this disclosure, "(meth)acrylic polymer" refers to a polymer having a structure obtained, for example, by polymerizing a component comprising at least one selected from acrylic acid, methacrylic acid, acrylates, methacrylates, monomers having an acryloyl group, and monomers having a methacryloyl group. The aforementioned component may or may not contain substances other than at least one selected from acrylic acid, methacrylic acid, acrylates, methacrylates, monomers having an acryloyl group, and monomers having a methacryloyl group.

[0064] In this disclosure, "acrylic monomer" refers, for example, to a monomer that includes at least one selected from acrylic acid, acrylates, and monomers having an acryloyl group.

[0065] In this disclosure, "isocyanate crosslinking agent" refers, for example, to a crosslinking agent having an isocyanate group (isocyanate alkyl group) in its molecule. In this disclosure, the number of isocyanate groups (isocyanate alkyl groups) in one molecule of the isocyanate crosslinking agent is not particularly limited, but is preferably two or more, for example, two, three, or four, and the upper limit is not particularly limited, for example, ten or less.

[0066] In this disclosure, "epoxy crosslinking agent" refers, for example, to a crosslinking agent having epoxy groups in its molecule. In this disclosure, the number of epoxy groups in one molecule of an epoxy crosslinking agent is not particularly limited, but is preferably two or more, for example, two, three, or four, and the upper limit is not particularly limited, for example, ten or less.

[0067] [1. Laminated structures, optical components, and optical devices]

[0068] As described above, the laminate of this disclosure includes a void layer and an adhesive layer, wherein the adhesive layer is directly laminated on one or both sides of the void layer. In this disclosure, the "direct lamination" of the adhesive layer on the void layer can be, for example, the adhesive layer being in direct contact with the void layer, or the adhesive layer being laminated on the void layer through the intermediate layer.

[0069] Figure 1 (a) shows a cross-sectional view illustrating an example of the structure of the laminate of this disclosure. As shown, in this laminate 10, the adhesive layer 12 is directly laminated onto one side of the void layer 11. Furthermore, Figure 1 (b) shows another example of the configuration of the laminate of the present disclosure. As shown, the adhesive layer 12 is directly laminated on both sides of the void layer 11 of the laminate 10a.

[0070] Furthermore, as described above, in the laminated body of this disclosure, an intermediate layer may exist between the aforementioned void layer and the aforementioned adhesive layer, the aforementioned intermediate layer being a layer formed by the aforementioned void layer and the aforementioned adhesive layer being integrally bonded together. Figure 2 An example of such a stacked body of the present disclosure is shown in the figure. Figure 2 As shown in the figure, the laminate 10b of (a) has an adhesive layer 12 directly laminated on one side of the void layer 11. This laminate 10b has an intermediate layer 13 between the void layer 11 and the adhesive layer 12, except that... Figure 1 (a) is the same as the laminate 10. The intermediate layer 13 is a layer formed by bonding the void layer 11 and the adhesive layer 12 together. Figure 2 (b) The laminate 10c is shown in the figure, in which the adhesive layer 12 is directly laminated on both sides of the void layer 11. This laminate 10c, except for the intermediate layer 13 between the void layer 11 and each adhesive layer 12, is... Figure 1 (b) is the same as the laminate 10a. (and) Figure 2 (a) Similarly, the intermediate layer 13 is a layer formed by combining the void layer 11 and the adhesive layer 12 together.

[0071] Furthermore, the laminate disclosed herein may include other constituent elements besides the aforementioned void layer, adhesive layer, and intermediate layer, or it may not include other constituent elements. The aforementioned other constituent elements are not particularly limited; for example, they may be a substrate. The aforementioned substrate is also not particularly limited; for example, it may be a film (e.g., a resin film), a glass plate, etc., as described later. Figure 3 An example of such a stacked body of the present disclosure is shown in the figure. Figure 3As shown in the figure, the laminate 10d of (a) has a substrate 14 directly contacting the surface of the void layer 11 opposite to the adhesive layer 12 and the surface of the adhesive layer 12 opposite to the void layer 11, respectively. Figure 2 (a) is the same as the stack 10b. Figure 3 (b) The laminate 10e is shown in the figure. Except for the substrate 14 directly contacting the adhesive layers 12 on the surfaces opposite to the void layer 11 on both sides, it is... Figure 2 (b) is the same as the laminate 10c. Figure 3 (a) and Figure 3 In (b), substrates 14 are provided on both sides of the laminate. However, it should be noted that this disclosure is not limited to this; for example, substrates 14 may be provided on only one side. Additionally, in Figure 3 (a) and Figure 3 In (b), the substrate 14 is disposed in direct contact with the void layer 11 or the adhesive layer 12. However, this disclosure is not limited to this; for example, other constituent elements may exist between the substrate 14 and the void layer 11 or the adhesive layer 12. These other constituent elements are not particularly limited; for example, they may be optical functional layers. These optical functional layers are also not particularly limited; for example, they may be optical functional layers used in general optical films, such as microlens films, prism films, diffusion films, polarizing reflection films, polarizing films, retardation films, high refractive index layers, etc.

[0072] For the laminates disclosed herein, for example, the light transmittance of the laminate of the aforementioned adhesive layer and the aforementioned void layer, or the laminate of the aforementioned adhesive layer, the aforementioned intermediate layer, and the aforementioned void layer, can be 80% or more. Furthermore, for example, the haze of the aforementioned laminate can be 3% or less. The aforementioned light transmittance can be, for example, 82% or more, 84% or more, 86% or more, or 88% or more, with no particular upper limit, ideally 100%, but for example, 95% or less, 92% or less, 91% or less, or 90% or less. The haze of the aforementioned laminate can be measured, for example, by the same method as the haze measurement of the void layer described later. Furthermore, the aforementioned light transmittance is the transmittance of light with a wavelength of 550 nm, and can be measured, for example, by the following measurement method.

[0073] (Methods for measuring light transmittance)

[0074] Using a U-4100 spectrophotometer (a trade name of Hitachi, Ltd.), the above-mentioned laminate was used as the sample to be measured. Then, the total light transmittance (transmittance) of the above-mentioned sample was measured with the total light transmittance of air set to 100%. The value of the above-mentioned total light transmittance (transmittance) was taken as the value measured at a wavelength of 550 nm.

[0075] For the laminate of this disclosure, for example, the adhesive force or bonding strength of the aforementioned adhesive layer can be 0.7 N / 25 mm or more, 0.8 N / 25 mm or more, 1.0 N / 25 mm or more, or 1.5 N / 25 mm or more, or less than 50 N / 25 mm, less than 30 N / 25 mm, less than 10 N / 25 mm, less than 5 N / 25 mm, or less than 3 N / 25 mm. From the viewpoint of avoiding peeling risk during operation when bonding the laminate to other layers, it is preferable that the adhesive force or bonding strength of the aforementioned adhesive layer is not too low. Furthermore, from the viewpoint of re-operation during re-lamination, it is preferable that the adhesive force or bonding strength of the aforementioned adhesive layer is not too high. The adhesive force or bonding strength of the aforementioned adhesive layer can be measured, for example, as described below.

[0076] (Methods for measuring adhesive strength or bonding strength)

[0077] A sample of the laminated film of this disclosure (a laminated film on a resin film substrate with the laminate of this disclosure formed thereon) was taken to obtain a strip-shaped sample of 50 mm × 140 mm. The sample was fixed to a stainless steel plate with double-sided tape. An acrylic adhesive layer (20 μm thick) was laminated onto a PET film (T100: manufactured by Mitsubishi Resin Film Co., Ltd.). Adhesive tape pieces cut into 25 mm × 100 mm were attached to the opposite side of the laminated film of this disclosure from the resin film, and lamination was performed with the PET film. Next, the sample was clamped in an Autograph tensile testing machine (manufactured by Shimadzu Corporation: AG-Xplus) with a chuck spacing of 100 mm, and a tensile test was performed at a tensile speed of 0.3 m / min. The average test force of the 50 mm peel test was taken as the adhesive peel strength, i.e., the adhesive force. In addition, the adhesive force can also be measured by the same measurement method. In this disclosure, "adhesive force" and "adhesive strength" are not clearly distinguished.

[0078] The laminates disclosed herein can be formed on substrates such as membranes. The membrane may be, for example, a resin membrane. It should be noted that, generally, materials with thinner thicknesses are sometimes referred to as "membranes" and materials with thicker thicknesses as "sheets" to distinguish between them; however, in this disclosure, no special distinction is made between "membranes" and "sheets".

[0079] The aforementioned substrate is not particularly limited, and preferred materials include, for example, substrates made of thermoplastic resins, glass substrates, inorganic substrates such as silicon, plastics molded from thermosetting resins, semiconductor components, and carbon fiber materials such as carbon nanotubes, but are not limited to these. Examples of the forms of the aforementioned substrates include films and sheets. Examples of the aforementioned thermoplastic resins include, for example, polyethylene terephthalate (PET), acrylic resins, cellulose acetate propionate (CAP), cyclic olefin polymers (COP), cellulose triacetate (TAC), polyethylene naphthalate (PEN), polyethylene (PE), and polypropylene (PP).

[0080] The optical components disclosed herein are not particularly limited; for example, they may be optical films comprising the laminates described above.

[0081] The optical device (optical component) disclosed herein is not particularly limited; for example, it can be an image display device or an illumination device. Examples of image display devices include liquid crystal displays, organic EL (electroluminescence) displays, and micro LED (light emitting diode) displays. Examples of illumination devices include organic EL illumination.

[0082] [2. Porous layer]

[0083] The following description uses examples of the aforementioned void layer (hereinafter sometimes referred to as "the void layer of this disclosure") in the laminated body of this disclosure. However, it should be noted that the void layer of this disclosure is not limited to this.

[0084] For the porosity layer of this disclosure, for example, the porosity can be 35% or more by volume, and the peak pore size can be less than 50 nm. However, this is only an example, and the porosity layer of this disclosure is not limited thereto.

[0085] The aforementioned porosity can be, for example, 35% or more by volume, 38% or more by volume, or 40% or more by volume, or it can be 90% or less by volume, 80% or less by volume, or 75% or less by volume. The porosity layer of this disclosure can, for example, be a high porosity layer with a porosity of 60% or more by volume.

[0086] The porosity described above can be determined, for example, by the following measurement methods.

[0087] (Methods for determining porosity)

[0088] If the layer being measured for porosity is a single layer containing only voids, the ratio (volume ratio) of the layer's constituent material to air can be calculated using conventional methods (e.g., by measuring weight and volume to calculate density), and thus the porosity (volume %) can be calculated. Furthermore, since refractive index and porosity are related, the porosity can also be calculated, for example, from the refractive index value of the layer. Specifically, the porosity can be calculated, for example, using the refractive index value measured by an ellipsometer and the Lorentz-Lorenz formula.

[0089] The porous layer disclosed herein can be manufactured, for example, by chemical bonding of gel fragments (microporous particles) as described below. In this case, for convenience, the pores of the porous layer can be divided into the following three types (1) to (3).

[0090] (1) The pores inherent in the raw material gel itself (within the particles)

[0091] (2) The voids in the gel fragment unit

[0092] (3) Gaps between the fragments caused by the accumulation of gel fragments

[0093] The voids in (2) above are independent of the size and shape of the gel fragments (microporous particles). They are voids that can be formed within each particle group generated by pulverizing the gel, which are different from those formed during pulverization as described in (1). In addition, the voids in (3) above are voids that are generated during pulverization (e.g., medialess pulverization) due to the uneven size and shape of the gel fragments (microporous particles). The void layer of this disclosure has appropriate porosity and peak pore size by having voids such as those described in (1) to (3) above.

[0094] Furthermore, the aforementioned peak pore size can be, for example, 5 nm or more, 10 nm or more, or 20 nm or more, or 50 nm or less, 40 nm or less, or 30 nm or less. In the porous layer, when the porosity is high, if the peak pore size is too large, light scattering occurs, resulting in opacity. Additionally, in this disclosure, there is no particular limitation on the lower limit of the peak pore size of the porous layer, but if the peak pore size is too small, it is difficult to increase the porosity; therefore, it is preferable that the peak pore size is not too small. In this disclosure, the peak pore size can be measured by, for example, the method described below.

[0095] (Method for determining peak pore size)

[0096] The peak pore size was calculated using a pore distribution / specific surface area measuring device (BELLSORP MINI / MICRO TRACK BELL), BJH curves and BET curves calculated based on nitrogen adsorption, and isothermal adsorption lines.

[0097] In addition, the thickness of the void layer disclosed herein is not particularly limited, and can be, for example, 100 nm or more, 200 nm or more, or 300 nm or more, or 10,000 nm or less, 5,000 nm or less, or 2,000 nm or less.

[0098] The porous layer of this disclosure, as described later, disrupts the three-dimensional structure of the porous gel by using pulverized material, forming a new three-dimensional structure different from that of the porous gel. In this way, the porous layer of this disclosure becomes a layer capable of forming new pore structures (new porous structures) that cannot be obtained from layers formed by the aforementioned porous gel, thereby enabling the formation of nanoscale porous layers with high porosity. Furthermore, for the porous layer of this disclosure, for example, in the case where the porous layer is an organosilicon porous body, for example, the number of siloxane bond functional groups in the silicon compound gel is adjusted, and the pulverized material is chemically bonded to each other. Here, "organosilicon porous body" refers to a polymeric porous body containing siloxane bonds, for example, a porous body containing silsesquioxanes as structural units. Furthermore, since chemical bonding (e.g., cross-linking) occurs during the bonding process after the formation of a new three-dimensional structure as a precursor to the aforementioned porous layer, the porous layer of this disclosure, even when the porous layer is, for example, a functional porous body, has a porous structure but maintains sufficient strength and flexibility. Therefore, according to this disclosure, a porous layer can be easily and conveniently applied to various objects.

[0099] The porous layer of this disclosure comprises, for example, fragments of a porous gel as described later, and these fragments are chemically bonded together. In the porous layer of this disclosure, the form of the chemical bonding (chemical adhesion) between the fragments is not particularly limited; specific examples of such chemical bonding include cross-linking bonds. It should be noted that the method for chemically bonding the fragments together is as detailed in the above-described method for manufacturing the porous layer.

[0100] The aforementioned crosslinking bonds are, for example, siloxane bonds. Examples of siloxane bonds include, for example, T2, T3, and T4 bonds, as shown below. In the case of the organosilicon porous body of this disclosure having siloxane bonds, for example, any one type of bond, any two types of bonds, or all three types of bonds may be present. Among the aforementioned siloxane bonds, a higher ratio of T2 and T3 results in greater flexibility and a better expectation of the original gel properties, but the film strength becomes brittle. On the other hand, a higher ratio of T4 in the aforementioned siloxane bonds tends to result in stronger film, but the pore size becomes smaller, and the flexibility becomes brittle. Therefore, it is preferable, for example, to change the ratio of T2, T3, and T4 according to the application.

[0101] [Chemical Formula 1]

[0102]

[0103] When the void layer of this disclosure has the above-mentioned siloxane bonds, for example, when T2 is relatively represented as "1", the ratio of T2, T3 and T4 is T2: T3: T4 = 1: [1~100]: [0~50], 1: [1~80]: [1~40], 1: [5~60]: [1~30].

[0104] Furthermore, for the porous layer of this disclosure, it is preferable, for example, that the silicon atoms contained therein form siloxane bonds. As a specific example, the proportion of unbonded silicon atoms (i.e., residual silanols) among all the silicon atoms contained in the above-mentioned organosilicon porous body is, for example, less than 50%, less than 30%, or less than 15%.

[0105] Furthermore, as described above, the void layer of this disclosure may, for example, be substantially free of fluorine compounds. By making the void layer substantially free of fluorine compounds, for example, the penetration of adhesives or binders into the voids of the void layer can be further suppressed, resulting in the further suppression of the increase in refractive index after the heat durability test.

[0106] The void layer of this disclosure, for example, has a porous structure. In this disclosure, the void size refers to the diameter of the major axis of the void (cavity), which is the diameter of the minor axis. The void size is, for example, 5 nm to 50 nm. The lower limit of the void size is, for example, 5 nm or more, 10 nm or more, or 20 nm or more, and the upper limit is, for example, 50 nm or less, 40 nm or less, or 30 nm or less, with a range, for example, 5 nm to 50 nm and 10 nm to 40 nm. Regarding the void size, the preferred void size is determined according to the intended use of the void structure; therefore, for example, it needs to be adjusted to the desired void size according to the purpose. The void size can be evaluated, for example, by the following methods.

[0107] (SEM observation of the cross-section of the void layer)

[0108] In this disclosure, the morphology of the void layer can be observed and analyzed using SEM (scanning electron microscope). Specifically, for example, the void layer can be processed by FIB under cooling (accelerating voltage: 30 kV), and the resulting cross-sectional sample can be imaged at 100,000x magnification using an FIB-SEM (manufactured by FEI: trade name Helios NanoLab600, accelerating voltage: 1 kV).

[0109] (Evaluation of gap size)

[0110] In this disclosure, the aforementioned pore size can be quantified using the BET test method. Specifically, 0.1 g of the sample (the pore layer of this disclosure) is placed into the capillary of a pore distribution / specific surface area measuring device (BELLSORP MINI / MICRO TRACK BELL's trade name), and then subjected to reduced pressure drying at room temperature for 24 hours to degas the gas within the pore structure. Then, by adsorbing nitrogen onto the sample, BET curves, BJH curves, and adsorption isotherms are plotted to determine the pore distribution, thereby evaluating the pore size.

[0111] The void layer of this disclosure can have a porous structure (multi-pore structure) as described above, for example, it can be an open-pore structure with continuous pore structures. An open-pore structure refers to a state where, for example, the pore structures in the void layer are three-dimensionally connected, or the internal voids of the pore structures are continuous. When a porous body has an open-pore structure, the porosity occupied in the bulk can be increased, but when using closed-pore particles such as hollow silica, an open-pore structure cannot be formed. In contrast, in the void layer of this disclosure, since the sol particles (the pulverized material forming the porous gel of the sol) have a three-dimensional dendritic structure, these dendritic particles settle / accumulate in the coating film (a coating film containing the sol of the pulverized porous gel of the above), thereby easily forming an open-pore structure. Furthermore, in the void layer of this disclosure, it is more preferable to form an integral structure with a plurality of fine pores distributed within the open-pore structure. The aforementioned overall structure refers to a hierarchical structure, for example, existing in the form of a structure with fine nanopores at the nanoscale and an open structure formed by a collection of the same nanopores. When forming the aforementioned overall structure, for example, the fine pores can impart membrane strength, and the large open pores can impart high porosity, thereby simultaneously achieving membrane strength and high porosity. To form the aforementioned overall structure, for example, it is important to first control the pore distribution of the generated pore structure in the porous gel during the pre-pulverization stage. Furthermore, for example, when pulverizing the porous gel, the overall structure can be formed by controlling the particle size distribution of the pulverized material to a desired size.

[0112] In the void layer of this disclosure, there is no particular limitation on the haze characterizing transparency, the lower limit of which is, for example, more than 0.1%, more than 0.2%, more than 0.3%, and the upper limit of which is, for example, less than 10%, less than 5%, less than 3%, and the range is, for example, 0.1~10%, 0.2~5%, 0.3~3%.

[0113] The aforementioned haze can be measured using, for example, the method described below.

[0114] (Evaluation of haze)

[0115] The void layer (the void layer of this disclosure) was cut into 50mm × 50mm pieces and placed in a haze meter (manufactured by Murakami Color Technology Research Institute Co., Ltd.: HM-150) to measure the haze. The haze value was calculated using the following formula.

[0116] Haze (%) = [Diffusion transmittance (%) / Total light transmittance (%)] × 100 (%)

[0117] Regarding the aforementioned refractive index, the refractive index of a medium is generally defined as the ratio of the wavefront propagation speed of light in a vacuum to the propagation speed within the medium. The refractive index of the void layer in this disclosure is not particularly limited, but its upper limit is, for example, less than 1.3, less than 1.3, less than 1.25, less than 1.2, or less than 1.15; its lower limit is, for example, more than 1.05, more than 1.06, or more than 1.07; and its range is, for example, more than 1.05 and less than 1.3, more than 1.05 and less than 1.3, more than 1.05 and less than 1.25, more than 1.06 and less than 1.2, or more than 1.07 and less than 1.15.

[0118] In this disclosure, unless otherwise specified, the refractive index mentioned above refers to the refractive index measured at a wavelength of 550 nm. Furthermore, the method for measuring the refractive index is not particularly limited; for example, it can be measured by the methods described below.

[0119] (Evaluation of refractive index)

[0120] A laminated sample with adhesive bonded to a void layer was prepared. The prism of a prism coupler (manufactured by Metricon) was fitted tightly against the substrate side of the sample, and the critical angle for total internal reflection was measured using a laser. The refractive index was calculated based on the value of this critical angle.

[0121] The thickness of the void layer disclosed herein is not particularly limited, but its lower limit is, for example, 0.05 μm or more or 0.1 μm or more, and its upper limit is, for example, 1000 μm or less or 100 μm or less, and its range is, for example, 0.05 to 1000 μm or 0.1 to 100 μm.

[0122] The morphology of the void layer disclosed herein is not particularly limited; for example, it can be membrane-like or block-like.

[0123] The method for manufacturing the void layer disclosed herein is not particularly limited, and can be manufactured by methods described in International Publication No. 2019 / 065999 and International Publication No. 2019 / 065803. The descriptions in those publications are incorporated herein by reference.

[0124] [3. Adhesive and bonding agent application solution]

[0125] In the laminates of this disclosure, as described above, the adhesive layer can be formed using an adhesive application liquid. In this disclosure, as will be stated below, "adhesive" and "adhesive" are not necessarily clearly distinguishable. In this disclosure, unless otherwise specified, the term "adhesive" encompasses both "adhesive" and "adhesive." The adhesive application liquid may, for example, contain the aforementioned (meth)acrylic polymer; alternatively, it may contain, for example, the aforementioned monomeric silane coupling agent; furthermore, it may contain, for example, a crosslinking agent (e.g., isocyanate crosslinking agent, epoxy crosslinking agent); and, for example, may further contain a monomer having one or two reactive double bonds in one molecule, and an organic peroxide. The adhesive application liquid is not particularly limited, as exemplified below.

[0126] In the above-mentioned adhesive coating liquid, for example, the above-mentioned (meth)acrylic polymer is a (meth)acrylic polymer containing, for example, 3 to 20% by mass of heterocyclic acrylic monomers, polymerizable functional groups, 0.5 to 5% by mass of (meth)acrylic acid, 0.05 to 2% by mass of (meth)acrylic acid hydroxyalkyl ester, and 83 to 96.45% by mass of (meth)acrylic acid alkyl ester, and this (meth)acrylic polymer can be used as the base polymer.

[0127] As heterocyclic acrylic monomers, heterocyclic acrylic monomers with polymerizable functional groups and heterocycles can be used, for example, without particular limitation. Examples of polymerizable functional groups include (meth)acryloyl groups and vinyl ether groups. Among these, (meth)acryloyl groups are preferred. Examples of heterocycles include morpholine rings, piperidine rings, pyrrolidine rings, and piperazine rings. Examples of heterocyclic acrylic monomers include N-acryloylmorpholine, N-acryloylpiperidine, N-methacryloylpiperidine, and N-acryloylpyrrolidine. Among these, N-acryloylmorpholine is preferred. It should be noted that heterocyclic acrylic monomers can improve the durability of any property, including heat resistance and moisture resistance, when the adhesive layer (adhesive bonding layer) is thinned. It should be noted that N-acryloylmorpholine is sometimes referred to as "ACMO" below.

[0128] Furthermore, heterocyclic acrylic monomers are preferred from the perspective of improving the adhesion of the adhesive layer (adhesive bonding layer) to the optical film. In particular, they are preferred from the perspective of improving the adhesion to cyclic polyolefins such as norbornene resins, and are especially preferred when using cyclic polyolefins as the optical film.

[0129] Relative to the total amount of monomer components forming (meth)acrylic polymers, heterocyclic acrylic monomers are used, for example, at a proportion of 3 to 20% by mass. The proportion of heterocyclic acrylic monomers can be, for example, 4 to 19% by mass or 6 to 18% by mass. From the viewpoint of heat resistance and moisture resistance when the adhesive layer (adhesive bonding layer) is thinned, it is preferable that the proportion of heterocyclic acrylic monomers is not less than the above range. Furthermore, from the viewpoint of moisture resistance when thinned, the proportion of heterocyclic acrylic monomers is preferably not more than the above range. Additionally, regarding the proportion of heterocyclic acrylic monomers, from the viewpoint of improving the adhesion of the adhesive layer (adhesive bonding layer), the proportion of heterocyclic acrylic monomers is preferably not more than the above range. Furthermore, from the viewpoint of adhesive strength, the proportion of heterocyclic acrylic monomers is preferably not more than the above range.

[0130] Acrylic acid is particularly preferred as (meth)acrylic acid.

[0131] The (meth)acrylic acid is used in a proportion of 0.5 to 20% by mass relative to the total amount of monomer components forming the (meth)acrylic acid polymer. The proportion of (meth)acrylic acid can be, for example, 0.5% or more by mass, 1% or more by mass, 2% or more by mass, or 3% or more by mass, and for example, 20% or less by mass, 15% or less by mass, 13% or less by mass, or 10% or less by mass. From the viewpoint of heat resistance when the adhesive layer (adhesive bonding layer) is thinned, the proportion of (meth)acrylic acid is preferably not less than the above range. Furthermore, from the viewpoint of heat resistance and moisture resistance when thinned, the proportion of (meth)acrylic acid is preferably not more than the above range. Additionally, from the viewpoint of adhesive strength, the proportion of (meth)acrylic acid is preferably not more than the above range.

[0132] As hydroxyalkyl methacrylates, hydroxyalkyl methacrylates having polymerizable functional groups and hydroxyl groups can be used without particular limitation. Preferably, hydroxyalkyl methacrylates include, for example, 2-hydroxyethyl methacrylate, 2-hydroxybutyl methacrylate, 3-hydroxypropyl methacrylate, 4-hydroxybutyl methacrylate, 6-hydroxyhexyl methacrylate, 8-hydroxyoctyl methacrylate, 10-hydroxydecyl methacrylate, and 12-hydroxylaurate methacrylate.

[0133] The hydroxyalkyl methacrylate is used, for example, at a ratio of 0.05 to 2% by mass relative to the total amount of monomer components forming the (meth)acrylate polymer. The proportion of the hydroxyalkyl methacrylate can be, for example, 0.075 to 1.5% by mass or 0.1 to 1% by mass. From the viewpoint of heat resistance when the adhesive layer (adhesive bonding layer) is thinned, the proportion of the hydroxyalkyl methacrylate is preferably not more than the above range. Furthermore, from the viewpoint of heat resistance and moisture resistance when thinned, the proportion of the hydroxyalkyl methacrylate is preferably not more than the above range. Additionally, from the viewpoint of adhesive strength, the proportion of the hydroxyalkyl methacrylate is preferably not more than the above range.

[0134] As an alkyl methacrylate, for example, the alkyl group of the alkyl ester may have an average number of carbon atoms of about 1 to 12. It should be noted that alkyl methacrylate refers to acrylates and / or methacrylates, and has the same meaning as (methyl) in this disclosure. Specific examples of alkyl methacrylates include: methyl methacrylate, ethyl methacrylate, n-butyl methacrylate, 2-ethylhexyl methacrylate, isooctyl methacrylate, isononyl methacrylate, lauryl methacrylate, etc., which may be used alone or in combination. Among these, alkyl methacrylates with 1 to 9 carbon atoms of the alkyl group are preferred.

[0135] Alkyl methacrylates are used, for example, in proportions of 83 to 96.45% by mass relative to the total amount of monomer components that form (meth)acrylic polymers. Alkyl methacrylates are typically the balance other than the heterocyclic acrylic monomers, (meth)acrylic acid, and hydroxyalkyl (meth)acrylic acid esters described above.

[0136] As a monomeric component for forming the above-mentioned (meth)acrylic polymers, for example, any monomer other than those described above may be used in a range of less than 10% of the total monomer amount without prejudice to the purpose of this disclosure.

[0137] Examples of monomers that can be cited as any of the above are: maleic anhydride, itaconic anhydride, and other monomers containing anhydride groups; caprolactone adducts of acrylic acid; styrene sulfonic acid, allyl sulfonic acid, 2-(meth)acrylamide-2-methylpropanesulfonic acid, (meth)acrylamide propanesulfonic acid, (meth)acrylate sulfonylpropyl ester, (meth)acryloyloxynaphthalene sulfonic acid, and other monomers containing sulfonic acid groups; 2-hydroxyethylacryloyl phosphate, and other monomers containing phosphate groups. Examples of nitrogen-containing vinyl monomers include: maleimide, N-cyclohexylmaleimide, N-phenylmaleimide; (meth)acrylamide, N,N-dimethyl(meth)acrylamide, N,N-diethyl(meth)acrylamide, N-hexyl(meth)acrylamide, N-methyl(meth)acrylamide, N-butyl(meth)acrylamide, N-hydroxymethyl(meth)acrylamide, N-hydroxymethylpropane(meth)acrylamide, and other (N-substituted) amide monomers; aminoethyl(meth)acrylate, aminopropyl(meth)acrylate, etc. (Meth)acrylate alkylaminoalkyl ester monomers such as N,N-dimethylaminoethyl acrylate, tert-butylaminoethyl acrylate, and 3-(3-pyridyl)propyl acrylate; (Meth)acrylate methoxyethyl ester and (Meth)acrylate ethoxyethyl ester and other (Meth)acrylate alkoxyalkyl ester monomers; and succinimide monomers such as N-(meth)acryloyloxymethylenesuccinimide, N-(meth)acryloyl-6-oxyhexamethylenesuccinimide, and N-(meth)acryloyl-8-oxyoctamethylenesuccinimide.

[0138] In addition, vinyl acetate, vinyl propionate, N-vinylpyrrolidone, methyl vinylpyrrolidone, vinylpyridine, vinylpiperidone, vinylpyrimidine, vinylpiperazine, vinylpyrazine, vinylpyrrole, vinylimidazolium, and vinylpyridine can also be used. Vinyl monomers such as azoles, vinylmorpholine, N-vinylcarboxylic amides, styrene, α-methylstyrene, and N-vinylcaprolactam; cyanoacrylate monomers such as acrylonitrile and methacrylonitrile; epoxy-containing acrylic monomers such as glycidyl methacrylate; polyethylene glycol acrylate monomers such as polyethylene glycol acrylate, polyethylene propylene glycol acrylate, polyethylene methoxy acrylate, and polyethylene propylene glycol acrylate; acrylate monomers such as tetrahydrofurfuryl acrylate, fluorinated methacrylates, organosilicon methacrylates, and 2-methoxyethyl acrylate.

[0139] In addition to the monomers mentioned above, silane monomers containing silicon atoms can be cited as examples of copolymerizable monomers. Examples of silane monomers include: 3-acryloyloxypropyltriethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, 4-vinylbutyltrimethoxysilane, 4-vinylbutyltriethoxysilane, 8-vinyloctyltrimethoxysilane, 8-vinyloctyltriethoxysilane, 10-methacryloyloxydecyltrimethoxysilane, 10-acryloyloxydecyltrimethoxysilane, 10-methacryloyloxydecyltriethoxysilane, 10-acryloyloxydecyltriethoxysilane, etc.

[0140] As described above, the weight-average molecular weight (Mw) of the (meth)acrylic polymer used in the adhesive layer of the laminate disclosed herein can be, for example, 1.5 million to 4 million. For example, the weight-average molecular weight can be 1.8 million to 3.8 million, or even 2 million to 3.5 million or 2.2 million to 3.3 million. From the viewpoint of heat resistance and moisture resistance when the adhesive layer (adhesive layer) is thinned, the weight-average molecular weight is preferably not less than the above range. Furthermore, from the viewpoint of durability, fit, and adhesion when thinned, the weight-average molecular weight is preferably not greater than the above range. It should be noted that in this disclosure, the weight-average molecular weight refers to a value calculated, for example, by measuring using GPC (gel permeation chromatography) and converting it to polystyrene.

[0141] There are no particular limitations on the manufacturing method of such (meth)acrylic acid polymers. For example, well-known manufacturing methods such as solution polymerization, bulk polymerization, emulsion polymerization, and various free radical polymerizations can be appropriately selected. In addition, the obtained (meth)acrylic acid polymers can be any copolymers such as random copolymers, block copolymers, and graft copolymers.

[0142] It should be noted that, in solution polymerization, solvents such as ethyl acetate and toluene can be used. As a specific example of solution polymerization, a polymerization initiator can be added to a stream of inert gas such as nitrogen, and the reaction can be carried out, for example, at a temperature of about 50-70°C for about 1-30 hours.

[0143] There are no particular restrictions on the polymerization initiators, chain transfer agents, and emulsifiers used in free radical polymerization; they can be selected appropriately. It should be noted that the weight-average molecular weight of (meth)acrylic acid polymers can be controlled based on the amount of polymerization initiator and chain transfer agent used, as well as the reaction conditions. The appropriate amount can be adjusted according to the types of these substances.

[0144] Examples of polymerization initiators include: 2,2'-azobisisobutyronitrile, 2,2'-azobis(2-amidinylpropane) dihydrochloride, 2,2'-azobis[2-(5-methyl-2-imidazolin-2-yl)propane] dihydrochloride, 2,2'-azobis(2-methylpropanediamine) disulfate, 2,2'-azobis(NN'-dimethyleneisobutyronitrile), 2,2'-azobis[N-(2-carboxyethyl)-2-methylpropanediamine] hydrate (manufactured by Wako Pure Chemical Industries, Ltd., VA-057), potassium persulfate, ammonium persulfate, di(2-ethylhexyl) peroxide dicarbonate, and di(4-ethylhexyl) peroxide dicarbonate. Peroxide initiators such as tert-butylcyclohexyl peroxide, disec-butyl peroxydicarbonate, tert-butyl peroxynedecanoate, tert-hexyl peroxynepentanoate, dilauroyl peroxide, dioctyl peroxide, 1,1,3,3-tetramethylbutyl peroxy2-ethylhexanoate, di(4-methylbenzoyl)peroxide, benzoyl peroxide, tert-butyl peroxyisobutyrate, 1,1-di(tert-hexylperoxy)cyclohexane, tert-butyl hydroperoxide, and hydroperoxide, as well as redox initiators combining peroxides and reducing agents, such as combinations of persulfates and sodium bisulfite, and combinations of peroxides and sodium ascorbate, are not limited to these.

[0145] The above-mentioned polymerization initiators can be used alone, or in combination of two or more. The content of the above-mentioned polymerization initiators, on a total basis, relative to 100 parts by mass of the monomer, can be, for example, about 0.005 to 1 part by mass or about 0.02 to 0.5 parts by mass.

[0146] It should be noted that when using, for example, 2,2'-azobisisobutyronitrile as a polymerization initiator to manufacture the above-mentioned (meth)acrylic polymers with a weight-average molecular weight, the amount of polymerization initiator relative to 100 parts by mass of the total monomer components can be, for example, about 0.06 to 0.2 parts by mass or about 0.08 to 0.175 parts by mass.

[0147] Examples of chain transfer agents include: dodecyl mercaptan, glycidyl mercaptan, thioglycolic acid, 2-mercaptoethanol, thioglycolic acid, 2-ethylhexyl thioglycolic acid, and 2,3-dimercapto-1-propanol. Chain transfer agents can be used alone or in combination of two or more. The total content of the above-mentioned chain transfer agents relative to 100 parts by mass of the monomeric components is, for example, about 0.1 parts by mass or less.

[0148] In addition, examples of emulsifiers used in emulsion polymerization include anionic emulsifiers such as sodium lauryl sulfate, ammonium lauryl sulfate, sodium dodecylbenzene sulfonate, ammonium polyoxyethylene alkyl ether sulfate, and sodium polyoxyethylene alkylphenyl ether sulfate; and nonionic emulsifiers such as polyoxyethylene alkyl ethers, polyoxyethylene alkylphenyl ethers, polyoxyethylene fatty acid esters, and polyoxyethylene-polyoxypropylene block polymers. These emulsifiers can be used alone or in combination of two or more.

[0149] Furthermore, as reactive emulsifiers, emulsifiers incorporating free radical polymerizable functional groups such as propylene groups and allyl ether groups specifically include, for example: AQUALON HS-10, HS-20, KH-10, BC-05, BC-10, BC-20 (all manufactured by Daiichi Kogyo Pharmaceutical Co., Ltd.), and ADEKA REASOAP SE10N (manufactured by Asahi Denko Co., Ltd.). Reactive emulsifiers enter the polymer chain after polymerization, thus improving water resistance, and are therefore preferred. The amount of emulsifier used relative to 100 parts by weight of the total monomer components is 0.3 to 5 parts by weight, and more preferably 0.5 to 1 part by weight for considerations of polymerization stability and mechanical stability.

[0150] The content of the (meth)acrylic polymer in the adhesive coating liquid is not particularly limited. For example, relative to the total mass of the adhesive coating liquid, it can be 3% or more by mass, or 5% or more by mass, or 30% or less by mass, 20% or less by mass, or 10% or less by mass.

[0151] Furthermore, the aforementioned adhesive coating liquid may, for example, contain a monomer having one or two reactive double bonds per molecule, or may not contain such a monomer. There is no particular limitation on the monomer having one or two reactive double bonds per molecule; from the viewpoint of the grafting reaction rate, acrylic monomers, vinyl monomers, methacrylic monomers, and allyl monomers are preferred, and acrylic monomers are more preferred. There is no particular limitation on the acrylic monomer; for example, the same monomers exemplified as monomer components of the aforementioned acrylic polymer can be used. In the monomer having one or two reactive double bonds per molecule, the structure of the side chain is not particularly limited; from the viewpoint of simultaneously achieving a high elastic modulus within an appropriate range and a reduction in the semi-polymer content, heterocyclic monomers are preferred.

[0152] When the above-mentioned adhesive coating liquid contains the monomer having one or two reactive double bonds in one molecule, its content is not particularly limited. In the above-mentioned adhesive coating liquid, for example, relative to the total mass of the above-mentioned (meth)acrylic polymer, it can be more than 0.1% by mass, more than 0.5% by mass, or more than 1% by mass, or for example, less than 30% by mass, less than 20% by mass, or less than 10% by mass.

[0153] The laminate disclosed herein improves the durability of the adhesive layer formed by the adhesive coating liquid by including a monomeric silane coupling agent, particularly exhibiting excellent durability in humidified environments and maintaining high durability even after prolonged storage. Here, in this disclosure, the adhesive coating liquid can be, for example, an adhesive (adhesive composition). The adhesive layer can be, for example, an adhesive layer formed by the adhesive (adhesive composition). "Monomeric" refers to a monomer; in this disclosure, the molecular weight of the monomeric silane coupling agent can be, for example, 50 or more, 70 or more, 100 or more, or 150 or more, and for example, 5000 or less, 3000 or less, 2000 or less, or 1000 or less.

[0154] In this disclosure, by including a monomeric silane coupling agent in the adhesive layer, the initial refractive index of the void layer can be reduced compared to, for example, using an oligomeric silane coupling agent instead of the monomeric silane coupling agent.

[0155] The aforementioned monomeric silane coupling agents can be, for example, silane coupling agents having two or more alkoxysilyl groups within the molecule. Specific examples of such monomeric silane coupling agents having two or more alkoxysilyl groups within the molecule include: amino-containing silane coupling agents such as 3-aminopropyltrimethoxysilane, N-2-(aminoethyl)-3-aminopropylmethyldimethoxysilane, 3-triethoxysilyl-N-(1,3-dimethylbutylidene)propylamine, and N-phenyl-γ-aminopropyltrimethoxysilane; (meth)acryloylsilane coupling agents such as 3-acryloyloxypropyltrimethoxysilane and 3-methacryloyloxypropyltriethoxysilane; and isocyanate-containing silane coupling agents such as 3-isocyanatepropyltriethoxysilane. These coupling agents are non-volatile and, due to the presence of multiple alkoxysilyl groups, are effective in improving durability, and are therefore preferred. Examples of such coupling agents include Shin-Etsu Chemical Co., Ltd.'s trade names KBM-802, KBM-303, and KBE-9007.

[0156] The number of alkoxysilyl groups in the above-mentioned monomeric silane coupling agent is not particularly limited, but it is preferably two or more within the molecule. Furthermore, the amount of alkoxy groups in the above-mentioned monomeric silane coupling agent is preferably 10-60% by mass, more preferably 20-50% by mass, and even more preferably 20-40% by mass. The type of alkoxy group is not particularly limited, and examples include alkoxy groups with 1 to 6 carbon atoms such as methoxy, ethoxy, propoxy, butoxy, pentoxy, and hexoxy. Among these, methoxy and ethoxy are preferred, and methoxy is more preferred. It is also preferable that both methoxy and ethoxy groups are contained in one molecule.

[0157] The aforementioned monomeric silane coupling agents may, for example, contain epoxy groups. Additionally, the aforementioned monomeric silane coupling agents may, for example, contain anhydride groups.

[0158] The aforementioned monomeric silane coupling agents can be used alone or in combination of two or more. The content of the monomeric silane coupling agent, relative to 100 parts by weight of the aforementioned (meth)acrylic acid polymer, is as described above, and is 5.0 parts by weight or less, for example, 4.0 parts by weight or less, 3.0 parts by weight or less, 2.0 parts by weight or less, or 1.0 parts by weight or less, for example, 0.01 parts by weight or more, 0.02 parts by weight or more, 0.03 parts by weight or more, 0.05 parts by weight or more, or 0.1 parts by weight or more. By setting the content within the above range, the increase in the initial refractive index can be suppressed, thereby reducing the amount of refractive index change after the aforementioned heat durability test.

[0159] It should be noted that the fact that the adhesive layer of the laminate of this disclosure contains a silane coupling agent can be confirmed, for example, by TOF-SIMS (Time-of-Flight Secondary Ion Mass Spectrometry). Specifically, if the adhesive layer of the laminate of this disclosure is measured by TOF-SIMS, it can be confirmed whether the adhesive layer contains specific functional groups (e.g., trimethoxysiloxy, triethoxysiloxy, dimethoxymethylsilyl, etc.), thereby confirming whether the adhesive layer contains a silane coupling agent. The TOF-SIMS determination can be confirmed, for example, by the following measurement conditions.

[0160] [Sample Preparation / Determination Methods]

[0161] The adhesive layer of the laminate of this disclosure was adhered to a substrate made of ITO (indium tin oxide) vapor-deposited glass plate. After autoclaving (50°C, 5 atm × 15 min), the adhesive layer was peeled off from the substrate. TOF-SIMS measurements were performed on the surface of the substrate after peeling.

[0162] [Apparatus and Measurement Conditions]

[0163] TOF SIMS device: ION TO TOF SIMS5 (product name of Hitachi High-Tech Co., Ltd.)

[0164] Primary ions irradiated: Bi3 2＋

[0165] Primary ion acceleration voltage: 25kV

[0166] Measurement area: 200 μm square

[0167] ※A neutralizing gun with charge correction is used in the determination of alkali-free glass.

[0168] Alternatively, silane coupling agents other than the monomeric silane coupling agents described above may be added to the adhesive coating liquid (e.g., adhesive composition) used in this disclosure. Examples of other silane coupling agents besides monomeric silane coupling agents include oligomeric silane coupling agents.

[0169] The weight-average molecular weight (Mw) of the aforementioned oligomeric silane coupling agent can be, for example, 300 or more. The laminate of the present invention, by including the oligomeric silane coupling agent in the adhesive coating liquid, improves the durability of the adhesive layer formed by the adhesive coating liquid, particularly exhibiting excellent durability in humid environments, maintaining high durability even after long-term storage. Here, in the present invention, the adhesive coating liquid can be, for example, an adhesive (adhesive composition). The adhesive layer can be, for example, an adhesive layer formed by an adhesive (adhesive composition). Furthermore, here, "oligomeric" refers to a polymer with a monomer dimer (degree of polymerization 2) or higher and less than about 100 polymers (degree of polymerization), and the weight-average molecular weight of the oligomeric silane coupling agent is preferably about 300 to 30,000. It should be noted that, in the present invention, the degree of polymerization of the aforementioned oligomeric silane coupling agent is not particularly limited.

[0170] The aforementioned oligomer-type silane coupling agents can be, for example, silane coupling agents having two or more alkoxysilyl groups within the molecule. Specifically, examples include X-41-1053, X-41-1059A, and X-41-1056 manufactured by Shin-Etsu Chemical Co., Ltd. These coupling agents are non-volatile and, due to the presence of multiple alkoxysilyl groups, are effective in improving durability, thus being preferred.

[0171] The number of alkoxysilyl groups in the aforementioned oligomer-type silane coupling agent is not particularly limited, but it is preferably two or more within the molecule. Furthermore, the amount of alkoxy groups in the aforementioned oligomer-type silane coupling agent is preferably 10-60% by mass, more preferably 20-50% by mass, and even more preferably 20-40% by mass. The type of alkoxy group is not particularly limited, and examples include alkoxy groups with 1 to 6 carbon atoms such as methoxy, ethoxy, propoxy, butoxy, pentoxy, and hexoxy. Among these, methoxy and ethoxy are preferred, and methoxy is more preferred. It is also preferable that both methoxy and ethoxy groups are contained in one molecule.

[0172] As described above, the oligomer-type silane coupling agent may contain epoxy groups. The epoxy equivalent of the oligomer-type silane coupling agent is preferably 1000 g / mol or less, more preferably 500 g / mol or less, and even more preferably 300 g / mol or less. Furthermore, the lower limit of the epoxy equivalent is not particularly limited, but is preferably 200 g / mol or more.

[0173] The aforementioned oligomer-type silane coupling agent preferably contains epoxy groups, but may also contain anhydride groups. By using an oligomer-type silane coupling agent containing anhydride groups, compared with the case where no silane coupling agent is used, the change in refractive index after the aforementioned heat durability test can be reduced, thereby improving the adhesion between the adhesive layer and the low refractive index layer after the aforementioned heat durability test.

[0174] The aforementioned oligomer-type silane coupling agents can be used alone or in combination of two or more. The total content of the aforementioned oligomer-type silane coupling agent relative to 100 parts by weight of the aforementioned (meth)acrylic acid polymer can be, for example, 1 part by weight or less, preferably 0.2 parts by weight or less. By setting the content within the aforementioned range, the increase in the initial refractive index can be suppressed, thereby reducing the amount of refractive index change after the aforementioned heat durability test.

[0175] Other silane coupling agents besides the monomeric silane coupling agents mentioned above may be added without impairing the effects of this disclosure, and there is no particular limitation on the amount added.

[0176] Furthermore, as described above, the adhesive coating liquid may contain a crosslinking agent. The crosslinking agent is not particularly limited; examples include isocyanate crosslinking agents and epoxy crosslinking agents. As for the isocyanate crosslinking agent, there is no particular limitation; examples include aromatic isocyanates such as toluene diisocyanate and xylene diisocyanate, alicyclic isocyanates such as isophorone diisocyanate, and aliphatic isocyanates such as hexamethylene diisocyanate. There are no particular limitations on the aforementioned epoxy crosslinking agents. Examples include: bisphenol A / epicochlorohydrin type epoxy resins, ethylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, glycerol diglycidyl ether, glycerol triglycidyl ether, 1,6-hexanediol diglycidyl ether, trimethylolpropane triglycidyl ether, sorbitol polyglycidyl ether, polyglycerol polyglycidyl ether, pentaerythritol polyglycidyl erythritol, diglycerol polyglycidyl ether, 1,3′-bis(N,N-diglycidylaminomethyl)cyclohexane, N,N,N′,N′-tetraglycidyl-m-diphenyldimethylamine, etc.

[0177] More specifically, examples of the aforementioned isocyanate crosslinking agents include: lower aliphatic polyisocyanates such as butylene diisocyanate and hexamethylene diisocyanate; alicyclic isocyanates such as cyclopentene diisocyanate, cyclohexene diisocyanate, and isophorone diisocyanate; aromatic diisocyanates such as 2,4-toluene diisocyanate, 4,4'-diphenylmethane diisocyanate, phenyl diisocyanate, and polymethylene polyphenyl isocyanate; trimethylolpropane / toluene diisocyanate trimer adduct (manufactured by Nippon Polyurethane Industry Co., Ltd., trade name CORONATE L); trimethylolpropane / hexamethylene diisocyanate trimer adduct (manufactured by Nippon Polyurethane Industry Co., Ltd., trade name CORONATE HL); and isocyanurate derivatives of hexamethylene diisocyanate (manufactured by Nippon Polyurethane Industry Co., Ltd., trade name CORONATE). Isocyanate adducts such as HX, polyether polyisocyanates, polyester polyisocyanates, and their adducts with various polyols, as well as polyisocyanates obtained through multifunctionalization such as isocyanurate bonds, biuret bonds, and urethane bonds.

[0178] More specifically, examples of the aforementioned epoxy crosslinking agents include: "TETRAD C" manufactured by Mitsubishi Gas Chemical Co., Ltd., "TETRAD X" manufactured by Mitsubishi Gas Chemical Co., Ltd., and "S-610" manufactured by Synasia Co., Ltd.

[0179] The aforementioned crosslinking agents (e.g., isocyanate crosslinking agents, epoxy crosslinking agents) can be used alone, or in combination of two or more. However, in terms of the total content, relative to 100 parts by weight of the aforementioned (meth)acrylic polymer, the content of the aforementioned crosslinking agent may be, for example, 0.02 to 2 parts by weight, 0.04 to 1.5 parts by weight, or 0.05 to 1 part by weight. From the viewpoint of cohesion, the content of the aforementioned isocyanate crosslinking agent is preferably 0.02 parts by weight or more; on the other hand, from the viewpoint of suppressing or preventing the decrease in adhesive strength caused by excessive crosslinking formation, it is preferably 2 parts by weight or less. From the viewpoint of void retention rate, the content of the aforementioned epoxy crosslinking agent is preferably 0.01 parts by weight or more; on the other hand, from the viewpoint of peel durability, it is preferably 0.5 parts by weight or less.

[0180] In the aforementioned adhesive coating liquid, the crosslinking agent may, for example, consist only of either isocyanate crosslinking agents or epoxy crosslinking agents, or may further include other crosslinking agents besides isocyanate crosslinking agents or epoxy crosslinking agents, or may not include any other crosslinking agents. Examples of such other crosslinking agents include organic crosslinking agents and polyfunctional metal chelates. Examples of organic crosslinking agents include epoxy crosslinking agents and imine crosslinking agents. Isocyanate crosslinking agents and epoxy crosslinking agents are preferred as organic crosslinking agents. Polyfunctional metal chelates are chelates in which multivalent metal atoms are covalently or coordinately bonded to organic compounds. Examples of multivalent metal atoms include Al, Cr, Zr, Co, Cu, Fe, Ni, V, Zn, In, Ca, Mg, Mn, Y, Ce, Sr, Ba, Mo, La, Sn, Ti, etc. Examples of atoms that are covalently or coordinately bonded in organic compounds include oxygen atoms, and examples of organic compounds include alkyl esters, alcohols, carboxylic acids, ethers, and ketones.

[0181] Furthermore, the aforementioned adhesive coating liquid may or may not contain organic peroxides. The aforementioned organic peroxides are not particularly limited, and examples include: di(2-ethylhexyl) peroxide dicarbonate, di(4-tert-butylcyclohexyl) peroxide dicarbonate, disec-butyl peroxide dicarbonate, tert-butyl peroxydecanoate, tert-hexyl peroxypentanoate, tert-butyl peroxypentanoate, dilauroyl peroxide, dioctanoyl peroxide, 1,1,3,3-tetramethylbutyl peroxy-2-ethylhexanoate, di(4-methylbenzoyl) peroxide, dibenzoyl peroxide, tert-butyl peroxyisobutyrate, 1,1-di(tert-hexylperoxy)cyclohexane, tert-butyl hydroperoxide, etc. Only one type may be used, or multiple types may be used in combination.

[0182] When the above-mentioned adhesive coating liquid contains the above-mentioned organic peroxide, its content is not particularly limited. In the above-mentioned adhesive coating liquid, for example, relative to the total mass of the above-mentioned (meth)acrylic polymer, it can be 0.02% by mass or more, 0.1% by mass or more, 0.5% by mass or more, 1% by mass or more, or 2.5% by mass or more, for example, it can be 20% by mass or less, 10% by mass or less, 8% by mass or less, or 6% by mass or less.

[0183] The aforementioned adhesive coating liquid may further contain solvents, etc. The solvents are not particularly limited; for example, polymerization solvents used in the solution polymerization of the aforementioned (meth)acrylic polymers can be used directly.

[0184] Furthermore, in the aforementioned adhesive coating liquid, various additives such as tackifiers, plasticizers, glass fibers, glass beads, metal powders, fillers composed of other inorganic powders, pigments, colorants, antioxidants, ultraviolet absorbers, and silane coupling agents may be appropriately used as needed without departing from the purpose of this disclosure. Additionally, an adhesive layer (adhesive layer) containing microparticles and exhibiting light diffusivity can also be prepared.

[0185] The adhesive layer in the laminate of this disclosure can be formed using the aforementioned adhesive coating solution and, for example, by the method described later. For the adhesive layer, for example, in the molecular weight determination of the adhesive layer using gel permeation chromatography, the weight-average molecular weight of the sol portion of the adhesive layer can be 30,000 to 600,000. Furthermore, for example, in the molecular weight determination of the adhesive layer using gel permeation chromatography, the content of low molecular weight components with a molecular weight of 10,000 or less in the sol portion of the adhesive layer can be 20% by weight (mass %) or less. By setting the weight-average molecular weight of the sol portion or the content of low molecular weight components with a molecular weight of 10,000 or less in the sol portion to the aforementioned specific range, the adhesive is less likely to penetrate into the voids of the void layer. The weight-average molecular weight of the sol portion can, for example, be 50,000 or more, for example, 550,000 or less, or 500,000 or less, for example, 50,000 to 550,000 or 60,000 to 500,000. Furthermore, the content (proportion) of components with a molecular weight of 10,000 or less in the aforementioned sol portion relative to the total amount of the aforementioned sol portion (100% by mass) can, for example, be 20% by mass or less, or for example, 15% by mass or less, or 10% by mass or less. There is no particular limitation on the lower limit of the content (proportion) of components with a molecular weight of 10,000 or less in the aforementioned sol portion; for example, it can be 0% by mass or more, or for example, 3% by mass or more. The content (proportion) of components with a molecular weight of 10,000 or less in the aforementioned sol portion can, for example, be 3 to 15% by mass or 3 to 10% by mass.

[0186] [4. Manufacturing method of laminated bodies]

[0187] The manufacturing method of the laminated body disclosed herein is not particularly limited, and can be carried out, for example, by the manufacturing method described below. However, it should be noted that the following description is illustrative and does not constitute any limitation on this disclosure. It should also be noted that the void layer of this disclosure is not particularly limited, for example, as described above. Furthermore, the manufacturing method of the void layer of this disclosure is also as described above, without particular limitation, and can be manufactured, for example, by the methods described in International Publication No. 2019 / 065999 and International Publication No. 2019 / 065803.

[0188] The method for manufacturing the laminate disclosed herein may include, for example, an adhesive layer manufacturing step for manufacturing the aforementioned adhesive layer; and a bonding step for bonding the aforementioned adhesive layer to the aforementioned void layer. The method for manufacturing the aforementioned adhesive layer may include, for example, an adhesive coating process for applying the aforementioned adhesive coating liquid to a substrate; and a heat drying process for heating and drying the substrate coated with the aforementioned adhesive coating liquid. For example, by bonding the adhesive layer side of an adhesive tape or the like, on which the adhesive layer of the present disclosure is laminated on a substrate, to the void layer of the present disclosure, the aforementioned adhesive layer can be formed on the void layer of the present disclosure. In this case, the substrate of the aforementioned adhesive tape or the like can remain bonded or can be peeled off from the aforementioned adhesive layer. In particular, by peeling off the substrate to produce an adhesive sheet without a substrate (substrate-free) containing a void layer, the thickness can be significantly reduced, and the thickness increase of devices, etc., can be suppressed. In this disclosure, "adhesive" and "adhesive layer" refer, for example, to an agent or layer that is predicated on the re-peeling of the adhered object. In this disclosure, "adhesive agent" and "adhesive layer" refer, for example, to an agent or layer that is not predicated on the re-peeling of the adhered object. However, it should be noted that in this disclosure, it is not always possible to clearly distinguish between "adhesive" and "adhesive agent," nor is it always possible to clearly distinguish between "adhesive layer" and "adhesive layer." In this disclosure, for example as described above, the aforementioned adhesive layer can be manufactured using the aforementioned adhesive application liquid.

[0189] The manufacturing process of the aforementioned adhesive layer can be performed, for example, as described below. First, the adhesive coating liquid is manufactured by a mixing process in which all components of the adhesive coating liquid are mixed. For example, as described above, the adhesive coating liquid may contain the aforementioned (meth)acrylic polymer, and may further contain, for example, a crosslinking agent (e.g., an isocyanate crosslinking agent, an epoxy crosslinking agent). The adhesive coating liquid may, for example, contain the aforementioned (meth)acrylic polymer, a monomer having one or two reactive double bonds in one molecule, and an organic peroxide. In this case, if the adhesive coating liquid contains other components, these other components may also be mixed together. For example, the polymerization solvent used in manufacturing the (meth)acrylic polymer may not be removed, and it may be directly mixed as a component of the adhesive coating liquid. In addition, the manufacturing method of the adhesive coating liquid may include other processes besides the aforementioned mixing process, but it may also exclude them, and all components of the adhesive coating liquid may be mixed only through the aforementioned mixing process.

[0190] Next, the adhesive coating liquid is applied to the substrate (adhesive coating liquid application step). The substrate is not particularly limited; for example, it can be a film or similar substrate. Preferred substrates include, for example, thermoplastic resin substrates, glass substrates, inorganic substrates such as silicon, plastics molded from thermosetting resins, semiconductor components, and carbon fiber materials such as carbon nanotubes, but are not limited to these. Examples of substrate forms include films and sheets. Examples of thermoplastic resins include, for example, polyethylene terephthalate (PET), acrylic acid, cellulose acetate propionate (CAP), cyclic olefin polymers (COP), cellulose triacetate (TAC), polyethylene naphthalate (PEN), polyethylene (PE), and polypropylene (PP). Furthermore, in the adhesive coating liquid application step, the coating thickness of the adhesive coating liquid is not particularly limited; for example, it can be appropriately adjusted to achieve a given thickness of the dried adhesive layer. There is no particular limitation on the thickness of the adhesive layer after drying, for example, as described later.

[0191] Next, the substrate coated with the aforementioned adhesive liquid is subjected to heat drying (heat drying step). In this heat drying step, the heating temperature is not particularly limited, and can be, for example, 50°C or higher, 80°C or higher, 100°C or higher, or 155°C or higher, or, for example, 200°C or lower, 180°C or lower, or 160°C or lower. The heating drying time is not particularly limited, and can be, for example, 0.5 minutes or more, 1 minute or more, or 3 minutes or more, or, for example, 60 minutes or less, 30 minutes or less, 20 minutes or less, or 10 minutes or less. In this heat drying step, for example, a crosslinking reaction and graft polymerization occur between the aforementioned (meth)acrylic polymer and the crosslinking agent. As a result, for example, as described above, the amount of semi-polymer present in the adhesive liquid is reduced, and the adhesive layer does not easily penetrate into the voids of the void layer. Thus, the adhesive layer used in the laminate of this disclosure can be manufactured.

[0192] Next, the adhesive layer is bonded to the void layer (bonding process). This method is not particularly limited; for example, as described above, by bonding the adhesive layer side of an adhesive tape or similar material on which the adhesive layer of this disclosure is laminated on a substrate to the void layer of this disclosure, the adhesive layer can be formed on the void layer of this disclosure. In this way, the laminate of this disclosure can be manufactured.

[0193] In the method for manufacturing the laminate disclosed herein, a heating step may be further included after the bonding step, wherein the adhesive layer and the void layer are heated. Hereinafter, this heating step is sometimes referred to as an "aging step." In the heating step (aging step), the heating temperature is not particularly limited, and may be, for example, 40°C or higher, 45°C or higher, or 50°C or higher, or, for example, 80°C or lower, 70°C or lower, 60°C or lower, or 55°C or lower. The heating time is not particularly limited, and may be, for example, 1 minute or more, 10 minutes or more, 60 minutes or more, or 1800 minutes or more, or, for example, 3000 minutes or lower, 2800 minutes or lower, 2500 minutes or lower, or 2000 minutes or lower. In this aging step, for example, the void layer and the adhesive layer may fuse together to form the intermediate layer. Moreover, for example, as described above, the intermediate layer acts as a barrier, suppressing the reduction in porosity caused by the adhesive filling the voids in the void layer. It should be noted that the above-mentioned void layer and the above-mentioned adhesive layer being integrated can be either the adhesive layer being embedded in the void layer and undergoing chemical bonding, or the adhesive layer being embedded in the void layer.

[0194] The aforementioned adhesive layer protects the void layer from physical damage (especially abrasions). Furthermore, the adhesive layer is preferably one with excellent pressure resistance, ensuring that the void layer will not be damaged even when fabricated as a substrate-free adhesive sheet containing the void layer, but this is not particularly limited. Additionally, the thickness of the adhesive layer is not particularly limited, and for example, it can be 0.1–100 μm, 5–50 μm, 10–30 μm, or 12–25 μm.

[0195] The laminate thus obtained, as described above, can be further laminated with other films (layers) to form a laminated structure containing the aforementioned porous layer (porous structure). In this case, in the aforementioned laminated structure, the constituent elements can be laminated together, for example, through the aforementioned adhesive layer (adhesive or bonding agent).

[0196] For example, from an effectiveness perspective, the above-mentioned components can be laminated by using continuous processing of long strip films (so-called roll-to-roll, etc.), and when the substrate is a molded object / component, the substrate that has been batch-processed can also be laminated.

[0197] The following describes a method for forming the laminate of the present disclosure on a substrate (resin film), focusing on continuous processing steps. Figure 3 (a) will be used as an example of a 10d laminate. It should be noted that the film-forming method described below is only one example and is not limited to it.

[0198] It should be noted that the substrate described above can be the resin film described above. In this case, the void layer of this disclosure is obtained by forming the void layer on the substrate. Alternatively, after forming the void layer on the substrate, the void layer of this disclosure can also be obtained by laminating the void layer onto the resin film described above in the description of the void layer of this disclosure.

[0199] exist Figure 3In the manufacturing method of the laminate 10d in (a), for example, a void layer 11 is first formed on a substrate 14, then an adhesive layer 12 is formed on the void layer 11, and then an intermediate layer 13 is formed by bonding the void layer 11 and the adhesive layer 12 together. More specifically, the manufacturing method includes, for example, a coating step (1) of coating a substrate (resin film) 14 with a sol-particle liquid of pulverized gel-like compound to form a coating film; a drying step (2) of drying the sol-particle liquid to form a dried coating film; a chemical treatment step (e.g., a crosslinking step) of chemically treating the coating film (e.g., a crosslinking step) to form the void layer 11 (3); a bonding step (4) of bonding the adhesive layer 12 onto the void layer 11; and an intermediate layer forming step (5) of reacting the void layer 11 and the adhesive layer 12 to form the intermediate layer 13. There are no particular limitations on the method for manufacturing the sol-particle liquid of pulverized gel-like compound. The aforementioned sol-particle liquid can be manufactured, for example, by the methods described in International Publication No. 2019 / 065999 or International Publication No. 2019 / 065803. Alternatively, the aforementioned sol-particle liquid can also be manufactured, for example, by the method described in "Reference Example 1" of the embodiments of this application described later. It should be noted that, although not illustrated, as described above, the manufacturing method of the laminate of this disclosure further includes: an adhesive layer manufacturing step of manufacturing the adhesive layer using the aforementioned adhesive layer manufacturing method of this disclosure; and a bonding step of attaching the adhesive layer to the void layer. As described above, the manufacturing method of the adhesive layer of this disclosure includes: an adhesive coating step of applying the aforementioned adhesive coating liquid to a substrate; and a heating and drying step of heating and drying the substrate coated with the aforementioned adhesive coating liquid. The aforementioned chemical treatment step (crosslinking step) (3) corresponds to the "void layer forming step" for forming the void layer in the laminate of this disclosure. Furthermore, the intermediate layer forming process (5) is equivalent to the heating process (aging process) described above. The intermediate layer forming process (5) (hereinafter sometimes referred to as the "aging process") can, for example, simultaneously serve as a process to increase the strength of the void layer 11 (a cross-linking reaction process that causes a cross-linking reaction within the void layer 11). In this case, after the intermediate layer forming process (5), the void layer 11 changes into a void layer 11 with further increased strength. However, this disclosure is not limited to this; for example, the void layer 11 may remain unchanged after the intermediate layer forming process (5). Additionally, as described above, the bonding process (4) can be the bonding of an adhesive tape having an adhesive layer on a substrate, etc. Figure 3 In (a), the substrate 14 coated with the above-mentioned adhesive liquid (with the adhesive layer 12 formed) can be peeled off from the adhesive layer 12, for example, or it can remain on the adhesive layer 12 as is. Through the above steps (1) to (5), as Figure 3As shown in (a), a laminated film (laminated body) can be manufactured by sequentially stacking a void layer 11, an intermediate layer 13, and an adhesive layer 12 on a resin film 14. However, it should be noted that the intermediate layer formation step (5) may be omitted, and the laminate of this disclosure may not contain an intermediate layer. Furthermore, the manufacturing method of the laminate of this disclosure may appropriately include steps other than those described above, or may not include steps other than those described above. Additionally, for example, it may be possible to... Figure 3 (a) The laminated film (laminated body) 10d is further bonded to the adhesive layer 12 with another substrate 14. Additionally, Figure 3 In the laminated film (laminated body) 10d of (a), the adhesive layer 12 is only disposed on one side of the void layer 11, but it can also be disposed, for example, like Figure 3 (b) In the form of the laminate 10e, the adhesive layer 12 is disposed on both sides of the void layer 11.

[0200] In the above-described coating process (1), the coating method for the sol-particle liquid is not particularly limited, and a conventional coating method can be used. Examples of such coating methods include: slit coating, reverse gravure coating, micro-gravure coating, immersion coating, spin coating, brush coating, roller coating, flexographic printing, wire rod coating, spray coating, extrusion coating, curtain coating, and reverse coating. From the viewpoints of productivity and coating smoothness, extrusion coating, curtain coating, roller coating, and micro-gravure coating are preferred. The amount of sol-particle liquid applied is not particularly limited; for example, it can be appropriately set to achieve an appropriate thickness for the void layer 11. The thickness of the void layer 11 is not particularly limited, as described above.

[0201] In the drying process (2) described above, the sol-particle liquid is dried (i.e., the dispersion medium contained in the sol-particle liquid is removed) to form the dried coating film (the precursor of the porous layer). The drying conditions are not particularly limited, as described above.

[0202] Furthermore, in the above-described chemical treatment step (3), the dried coating film containing the catalyst or catalyst generator (e.g., photoactive catalyst, photocatalyst generator, thermally active catalyst, or thermal catalyst generator) added before coating is irradiated or heated, causing the fragments in the dried coating film to chemically bond (e.g., crosslink) with each other, thereby forming a void layer 11. The irradiation or heating conditions in the above-described chemical treatment step (3) are not particularly limited, as described above.

[0203] On the other hand, although not illustrated, the adhesive layer of this disclosure is manufactured separately through the aforementioned adhesive layer manufacturing process. Regarding the aforementioned adhesive layer manufacturing process (the method for manufacturing the adhesive layer of this disclosure), for example, it is as described above.

[0204] Further, the bonding process (4) and the intermediate layer formation process (5) are performed. As described above, the intermediate layer formation process (5) is a heating process that heats the adhesive layer 12 and the void layer 11 after the bonding process (4). For example, if the adhesive is an adhesive composition containing a polymer (e.g., a (meth)acrylic acid polymer) and a crosslinking agent, the polymer can be crosslinked by the crosslinking agent through the heating process. The heating process can also be performed simultaneously as a drying process for the adhesive. Alternatively, the heating process can also be performed simultaneously as the intermediate layer formation process (5). The temperature of the heating process is not particularly limited, for example, 70~160°C, 80~155°C, or 90~150°C. The time of the heating process is not particularly limited, for example, 1~10 minutes, 1~7 minutes, or 2~5 minutes.

[0205] Example

[0206] The embodiments of this disclosure will now be described. However, this disclosure is not limited to the following embodiments.

[0207] It should be noted that, in the following reference examples, embodiments, and comparative examples, unless otherwise specified, the parts (relative amounts) of each substance are parts by mass (parts by weight). In the following reference examples, embodiments, and comparative examples, the adhesive (adhesive composition) described later was used as the adhesive. In the following reference examples, embodiments, and comparative examples, "adhesive layer" is equivalent to "adhesive bonding layer." That is, in the following reference examples, embodiments, and comparative examples, unless otherwise specified, "adhesive layer" and "adhesive bonding layer" have the same meaning.

[0208] In addition, in the following reference examples, examples and comparative examples, the weight-average molecular weight (Mw) of the (meth)acrylic polymer, the gel fraction of the adhesive layer, the thickness of each layer and the refractive index were measured by the following measurement methods.

[0209] <Methods for determining the molecular weight of (meth)acrylic acid polymers>

[0210] The weight-average molecular weight (Mw) of the (meth)acrylic acid polymers was calculated based on the molecular weight distribution curve determined by gel permeation chromatography (GPC).

[0211] • Analytical apparatus: Waters, Alliance

[0212] ·Column: Made by Tosoh Corporation, G7000HXL+GMHXL+GMHXL

[0213] • Column dimensions: 7.8mm φ × 30cm each, totaling 90cm

[0214] Column temperature: 40℃

[0215] • Flow rate: 0.8 mL / min

[0216] Injection volume: 100μL

[0217] • Elution buffer: THF (acid-added)

[0218] • Detector: Differential refractometer (RI)

[0219] Standard sample: polystyrene

[0220] <Method for determining the gel fraction of adhesive bonding layers>

[0221] Approximately 0.1 g of the optical adhesive layer formed on the peeling surface of the diaphragm within one minute of its fabrication was scraped off and designated as Sample 1. Sample 1 was then wrapped with a Teflon (trade name "NTF1122", manufactured by Nitto Denko Co., Ltd.) film with a diameter of 0.2 μm and tied with kite string, designated as Sample 2. The weight of Sample 2 before the following tests was measured and designated as weight A. It should be noted that weight A is the total weight of Sample 1 (adhesive layer), the Teflon (trade name) film, and the kite string. The total weight of the Teflon (trade name) film and the kite string is designated as weight B. Next, Sample 2 was placed in a 50 ml container filled with ethyl acetate and allowed to stand at 23°C for one week. Then, Sample 2 was removed from the container and dried in a desiccator at 130°C for 2 hours to remove the ethyl acetate, and the weight of Sample 2 was measured. The weight of Sample 2 after the above tests was measured and designated as weight C. The gel fraction was then calculated using the following formula.

[0222] Gel fraction (mass %) = (CB) / (AB) × 100

[0223] <Methods for measuring thickness>

[0224] For the thickness of the adhesive layer, the thickness of the adhesive layer at five locations was measured using a micrometer, and the average value was obtained. For the thickness of the intermediate layer, the portion of the thickness with different contrast between the adhesive layer and the low-refractive-index layer in the SEM image was taken as the intermediate layer, and the average value of the thickness readings from two locations on the SEM image was obtained.

[0225] <Methods for Determining Refractive Index>

[0226] The refractive index was measured using the aforementioned evaluation method.

[0227] It should be noted that in the adhesive layers of the following reference examples, embodiments and comparative examples, it is presumed that the polymer (acrylic polymer) was cross-linked by a cross-linking agent through heating and drying of the applied adhesive, thus forming a cross-linked structure, but the cross-linked structure was not confirmed.

[0228] [Reference Example 1: Manufacturing of a coating liquid for forming a void layer]

[0229] First, a gel (organosilicon porous body) with a porous structure is produced by gelling (step (1)) and curing (step (2)) of the silicon compound. Then, the following steps (3) morphology control, (4) solvent replacement, and (5) gel pulverization are performed to obtain a coating liquid (liquid containing gel pulverization) for forming a void layer. It should be noted that in this reference example, the following steps (3) morphology control are performed as a different step from step (1). However, this disclosure is not limited to this, and the following steps (3) morphology control may be performed in step (1).

[0230] (1) Gelization of silicon compounds

[0231] 9.5 kg of MTMS, a precursor of silicon compounds, was dissolved in 22 kg of DMSO. 5 kg of a 0.01 mol / L aqueous solution of oxalic acid was added to the mixture, and the mixture was stirred at room temperature for 120 minutes, thereby hydrolyzing MTMS to produce tris(hydroxy)methylsilane.

[0232] After adding 3.8 kg of 28% ammonia solution and 2 kg of pure water to 55 kg of DMSO, the above-mentioned hydrolyzed mixture was further added, and the mixture was stirred at room temperature for 60 minutes. The liquid after stirring for 60 minutes was then poured into a stainless steel container with a length of 30 cm, a width of 30 cm, and a height of 5 cm and allowed to stand at room temperature to gel the tris(hydroxy)methylsilane, resulting in a gel-like silicon compound.

[0233] (2) Curing process

[0234] The gel-like silicon compound obtained by the above gelation treatment was aged at 40°C for 20 hours to obtain the aforementioned rectangular block gel. It is clear that since the amount of DMSO (a high-boiling-point solvent with a boiling point above 130°C) in the raw material is approximately 83% by mass of the total raw material, the gel contains at least 50% by mass of a high-boiling-point solvent with a boiling point above 130°C. Furthermore, it is clear that since the amount of MTMS (monomers that form the building blocks of the gel) in the raw material is approximately 8% by mass of the total raw material, the content of solvents with a boiling point below 130°C (in this case, methanol) generated through the hydrolysis of the monomers (MTMS) that form the building blocks of the gel is at least 20% by mass.

[0235] (3) Morphology control process

[0236] Water, serving as a displacement solvent, is allowed to flow into the gel synthesized in the 30cm×30cm×5cm stainless steel container through the above steps (1) and (2). Next, in the stainless steel container, a cutting tool is slowly inserted from the top of the gel to cut it into cuboids with dimensions of 1.5cm×2cm×5cm.

[0237] (4) Solvent replacement process

[0238] Next, the solvent replacement process was carried out as described in (4-1) to (4-3) below.

[0239] (4-1)

[0240] Following the above-mentioned "(3) morphology control process", the gel-like silicon compound was immersed in water at 8 times its weight and slowly stirred for 1 hour by means of water convection only. After 1 hour, the water was replaced with the same amount of water and stirred for another 3 hours. Then, the water was replaced again and then heated for 3 hours while slowly stirring at 60°C.

[0241] (4-2)

[0242] After (4-1), the water was replaced with isopropanol at 4 times the weight of the gel-like silicon compound, and the mixture was heated for 6 hours while stirring at 60°C.

[0243] (4-3)

[0244] Following (4-2), isopropanol was replaced with the same weight of isobutanol, and the mixture was heated at 60°C for 6 hours to replace the solvent in the aforementioned gel-like silicon compound with isobutanol. As described above, the gel for manufacturing the void layer of this disclosure was manufactured.

[0245] (5) Gel pulverization process

[0246] The gel (gel-like silicon compound) after the solvent replacement process in (4) above was pulverized in two stages: continuous emulsification dispersion (manufactured by Pacific Machine Co., Ltd., Milder MDN304 model) was performed in the first pulverization stage; and high-pressure media-free pulverization (manufactured by Sugino Machine Co., Ltd., STARBURST HJP-25005 model) was performed in the second pulverization stage. In this pulverization process, 43.4 kg of gel containing the gel-like silicon compound after the solvent replacement was added with 26.6 kg of isobutanol. The first pulverization stage was performed by circulating pulverization for 20 minutes, and the second pulverization stage was performed by pulverization at a pressure of 100 MPa. In this way, an isobutanol dispersion (liquid containing gel pulverization) containing nano-sized particles (the pulverized gel) was obtained. Subsequently, 224g of a 1.5% concentration solution of WPBG-266 (trade name, manufactured by Wako) in methyl isobutyl ketone was added to 3kg of the above-mentioned liquid containing gel pulverizer. Then, 67.2g of a 5% concentration solution of bis(trimethoxysilyl)ethane (manufactured by TCI) in methyl isobutyl ketone was added, followed by the addition of 31.8g of N,N-dimethylformamide and mixing to obtain the coating solution.

[0247] Thus, the coating liquid (containing gel fragments) for forming a void layer of this reference example (reference example 1) was manufactured. Furthermore, the peak pore size of the gel fragments (microporous particles) in the coating liquid (containing gel fragments) for forming a void layer was measured using the method described above, and the result was 12 nm.

[0248] [Reference Example 2: Formation of the adhesive layer]

[0249] The adhesive layer of this reference example (reference example 2) was formed by following the sequence of (1) to (2).

[0250] (1) Preparation of (meth)acrylic acid polymers

[0251] (Preparation of (meth)acrylic acid polymers (A1))

[0252] A monomer mixture containing 79.5 parts butyl acrylate, 15 parts N-acryloylmorpholine, 5 parts acrylic acid, and 0.5 parts 4-hydroxybutyl acrylate was added to a four-necked flask equipped with a stirring blade, thermometer, nitrogen inlet tube, and condenser. Further, relative to 100 parts of the monomer mixture, 0.1 parts of 2,2'-azobisisobutyronitrile (2,2'-Azobisisobutyronitrile) as a polymerization initiator was added along with 70 parts of ethyl acetate. After nitrogen purging by slowly stirring and introducing nitrogen, the liquid temperature in the flask was maintained at approximately 55°C for 2 hours to prepare a solution of a (meth)acrylic acid polymer (A1) with a weight-average molecular weight (Mw) of 3.4 million and an Mw / Mn ratio of 2.5.

[0253] (Preparation of (meth)acrylic acid polymer (A2))

[0254] In the preparation of (meth)acrylic polymer (A1), the added monomer composition was set as 79.5 parts of butyl acrylate, 7.5 parts of N-acryloylmorpholine, 5 parts of acrylic acid, and 0.5 parts of 4-hydroxybutyl acrylate. The polymerization reaction time was set to 8 hours, and other processes were carried out in the same manner to prepare a solution of (meth)acrylic polymer (A2) with a weight average molecular weight (Mw) of 2.9 million and Mw / Mn = 4.2.

[0255] (2) (Preparation of adhesive composition)

[0256] An acrylic adhesive composition was prepared by combining 100 parts of the solid component of (meth)acrylic polymer (A1) or (A2) with 0.5 parts of monomeric silane coupling agent (trade name "KBM-802" manufactured by Shin-Etsu Chemical Co., Ltd.), 0.2 parts of isocyanate crosslinking agent (trade name "CORONATE L" manufactured by Nippon Polyurethane Co., Ltd., an adduct of trimethylolpropane toluene diisocyanate), 0.1 parts of epoxy crosslinking agent (trade name "TETRAD C" manufactured by Mitsubishi Gas Chemical Co., Ltd.), and 0.2 parts of benzoyl peroxide (trade name "Nyper BMT" manufactured by Nippon Oils & Fats Co., Ltd.).

[0257] (3) (Formation of adhesive layer)

[0258] Next, the above acrylic adhesive composition was applied to one side of a polyethylene terephthalate membrane (separator: manufactured by Mitsubishi Chemical Polyester Film Co., Ltd., MRF38) treated with an organosilicon release agent, such that the thickness of the dried adhesive layer reached 10 μm. The membrane was then dried at 155°C for 1 minute to form an adhesive layer (adhesive bonding layer) on the surface of the membrane.

[0259] [Example 1]

[0260] (Manufacturing of laminates)

[0261] The high porosity layer forming coating solution prepared in Reference Example 1 was applied to an acrylic substrate and dried to form a porosity layer with a thickness of approximately 850 nm (porosity 59% by volume). Next, the porosity layer was subjected to UV irradiation (300 mJ). Then, a 10 μm thick adhesive layer obtained in Reference Example 2 (using a (meth)acrylic acid polymer (Al) in this embodiment) was bonded to the porosity layer and aged at 60°C for 20 h to produce the laminate of this embodiment.

[0262] [Examples 2-12 and Comparative Examples 1-2]

[0263] The laminates of Examples 2-12 and Comparative Examples 1-2 were manufactured as described below.

[0264] Regarding Examples 2-12 and Comparative Examples 1-2, the types of (meth)acrylic polymers were specified as shown in Table 1 below, the types and amounts (parts by mass) of monomeric silane coupling agents were specified as shown in Table 1 below, and the amounts (parts by mass) of crosslinking agents were specified as shown in Table 1 below. Otherwise, solutions of acrylic adhesive compositions used in the manufacture of the laminates of Examples 2-12 and Comparative Examples 1-2 were prepared in the same manner as in Example 1. Furthermore, using the above-mentioned solutions of acrylic adhesive compositions, adhesive layers were prepared in the same manner as in Example 1, and laminates of Examples 2-12 and Comparative Examples 1-2 were manufactured. It should be noted that in Table 1 below, all monomeric silane coupling agents were manufactured by Shin-Etsu Chemical Industry Co., Ltd., and the "type" of monomeric silane coupling agents refers to the trade names of Shin-Etsu Chemical Industry Co., Ltd.

[0265] [Heating Durability Test]

[0266] Furthermore, the laminates of this embodiment and the comparative example manufactured as described above were placed in an oven at 65°C and 95% relative humidity for 500 hours for a heat durability test. The change in refractive index before and after the heat durability test was calculated using the above mathematical formula (1). These results are shown in Table 1.

[0267] The evaluation criteria for the initial refractive index in Table 1 are as follows.

[0268] ◎: Less than 1.19

[0269] ○: 1.19 or higher and less than 1.20

[0270] ×: 1.20 or more

[0271] The evaluation criteria for the refractive index (change) after the heating durability test in Table 1 are as follows.

[0272] ◎: Less than 0.03

[0273] ○: 0.03 or higher and less than 0.04

[0274] ×: 0.04 or more

[0275] The evaluation criteria for the rate of change of refractive index after the heating durability test in Table 1 are as follows. It should be noted that the rate of change of refractive index (%) after the heating durability test in Tables 1 and 2 was calculated using (|n-n0| / n0)×100. n0, similar to the above mathematical formula (1), is the refractive index (initial refractive index) of the void layer before the heating durability test, and n, similar to the above mathematical formula (1), is the refractive index of the void layer after the heating durability test.

[0276] ◎: Less than 2.0%

[0277] ○: 2.0% or more but less than 3.0%

[0278] ×: 3.0% or more

[0279] The meanings of the text shown in Table 1 are as follows. Additionally, the numbers in Table 1 represent the amount (parts by mass) of each ingredient added.

[0280] [(Meth)acrylic polymers]

[0281] "A1" or "A2" indicates which of the (meth)acrylic polymers A1 and A2 described in Reference Example 2 above was used in the formed adhesive layer. It should be noted that the method for forming the adhesive layer is as described in Reference Example 2 above.

[0282] [Monomer-type silane coupling agent]

[0283] Type: Indicates the type of monomeric silane coupling agent used in each example and comparative example. As mentioned above, it is a trade name of Shin-Etsu Chemical Co., Ltd.

[0284] Functional group: indicates the type of functional group possessed by the monomeric silane coupling agent used in each embodiment and comparative example.

[0285] Methoxy or ethoxy: indicates that the monomeric silane coupling agent used in the examples and comparative examples has either a methoxy or ethoxy group, or a silanol group in the form of these groups after hydrolysis.

[0286] [Cross-linking agent]

[0287] Isocyanate: The adduct of trimethylolpropane toluene diisocyanate (trade name "CORONATE L" manufactured by Tosoh Corporation).

[0288] Epoxy: 1,3-bis(N,N-diglycidylaminomethyl)cyclohexane (trade name "TETRAD C" manufactured by Mitsubishi Gas Chemical Co., Ltd.)

[0289] Peroxide: Benzoyl peroxide (trade name "Nyper BMT" manufactured by Nippon Oils & Fats Co., Ltd.)

[0290]

[0291] As shown in Table 1 above, Examples 1-12, which used a monomeric silane coupling agent and had an addition amount of 5.0 parts by mass or less of the silane coupling agent, exhibited low initial refractive index, low refractive index (change) after the heat durability test, and excellent peel durability. In other words, the laminates of Examples 1-12, due to the adhesive's difficulty in penetrating the voids of the void layer, had low initial refractive index, excellent heat durability, and were able to achieve both these effects and strong adhesion between the adhesive layer and the low-refractive-index layer. Conversely, when the amount of monomeric silane coupling agent exceeded 5.0 parts by mass (Comparative Example 1), or when no silane coupling agent was used (Comparative Example 2), the adhesive easily penetrated the voids of the void layer, resulting in poor initial refractive index, heat durability, and adhesion between the adhesive layer and the low-refractive-index layer. More specifically, Comparative Example 1 had a poor initial refractive index, while Comparative Example 2 had a good initial refractive index but poor heat durability. It should be noted that no fluorine compounds were used in the formation of the void layer in Examples 1-12 and Comparative Examples 1-2, therefore the void layer does not contain fluorine compounds. Furthermore, the monomeric silane coupling agents used in Examples 1-12, as described in Table 1, have thiol, epoxy, isocyanate, amino, acryloyl, styrene, vinyl, isocyanurate, acetoacetyl, silyl, or carboxylic acid groups as functional groups, and any one of these functional groups achieves the aforementioned effects.

[0292] This disclosure may also be described, for example, as in the following notes. However, it should be noted that the following notes are examples, and this disclosure is not limited to these methods.

[0293] (Postscript 1)

[0294] A laminate comprising a void layer and an adhesive layer,

[0295] The aforementioned adhesive layer is directly laminated onto one or both sides of the aforementioned void layer.

[0296] The aforementioned adhesive layer is formed from an adhesive comprising a (meth)acrylic polymer and a monomeric silane coupling agent.

[0297] The content of the monomeric silane coupling agent is 5.0 parts by mass or less, relative to 100 parts by mass of the above (meth)acrylic polymer.

[0298] (Postscript 2)

[0299] According to the laminated body described in Appendix 1, wherein,

[0300] The weight-average molecular weight (Mw) of the above-mentioned (meth)acrylic acid polymers is 1.5 million to 4 million.

[0301] (Note 3)

[0302] According to the laminated body described in Appendix 1 or 2, wherein,

[0303] The aforementioned adhesive layer is formed from an adhesive comprising the aforementioned (meth)acrylic polymer and a crosslinking agent.

[0304] The gel fraction of the above-mentioned adhesives exceeds 85%.

[0305] (Postscript 4)

[0306] The laminate according to any one of Appendices 1 to 3, wherein,

[0307] The above-mentioned (meth)acrylic acid polymers contain 1 to 30% by mass of nitrogen-containing monomers as monomer units.

[0308] (Note 5)

[0309] According to the laminated body described in Appendix 4, wherein...

[0310] The nitrogen-containing monomers mentioned above are heterocyclic acrylic acid monomers.

[0311] (Note 6)

[0312] The laminate according to any one of Appendices 1 to 5, wherein,

[0313] The above-mentioned (meth)acrylic acid polymers contain 0.5 to 20% by mass of acrylic acid as monomer units.

[0314] (Note 7)

[0315] The laminate according to any one of Appendices 1 to 6, wherein,

[0316] The aforementioned void layer does not contain organic fluorine compounds.

[0317] (Postscript 8)

[0318] The laminate according to any one of Appendices 1 to 7, wherein,

[0319] Before and after a heating durability test at 65°C and 95% relative humidity for 500 hours, the change in refractive index of the above-mentioned porous layer satisfies the following mathematical formula (1):

[0320] |n-n0| < 0.04 (1)

[0321] In the above mathematical formula (1),

[0322] n is the refractive index of the aforementioned porous layer after the above-mentioned heat durability test.

[0323] n0 is the refractive index of the aforementioned void layer before the aforementioned heat durability test.

[0324] (Note 9)

[0325] The laminate according to any one of Appendices 1 to 8, wherein,

[0326] An intermediate layer exists between the aforementioned void layer and the aforementioned adhesive layer.

[0327] The aforementioned intermediate layer is formed by combining the aforementioned void layer and the aforementioned adhesive layer into one layer.

[0328] (Postscript 10)

[0329] According to the laminated body described in Appendix 9, wherein...

[0330] The thickness of the aforementioned intermediate layer is 10~100nm.

[0331] (Postscript 11)

[0332] An optical component comprising the laminate described in any one of Appendices 1 to 10.

[0333] (Postscript 12)

[0334] An optical device comprising the optical components described in Appendix 11.

[0335] Industrial applicability

[0336] As explained above, according to this disclosure, laminates, optical components, and optical devices can be provided that balance adhesive strength or bonding strength with the difficulty of impregnating the voids of the void layer with adhesives or binders. The applications of this disclosure are not particularly limited. For example, the optical devices of this disclosure are not particularly limited, and examples include image display devices and lighting devices. Examples of such image display devices include liquid crystal displays, organic EL displays, and miniature LED displays. Examples of such lighting devices include organic EL lighting. The laminates of this disclosure, for example, are particularly suitable for use under high-durability conditions such as automotive applications, as adhesives or binders do not easily impregnate the voids of the void layer, even under high temperature and high humidity conditions. Furthermore, the applications of the laminates of this disclosure are not limited to the optical components and optical devices of this disclosure, and can be used in a wide range of applications.

[0337] This application claims priority based on Japanese Application Special Hoc 2023-163762, filed on September 26, 2023, the entire contents of which are hereby incorporated.

Claims

1. A laminate comprising a void layer and an adhesive layer, The adhesive layer is directly laminated on one or both sides of the void layer. The adhesive layer is formed from an adhesive comprising a (meth)acrylic polymer and a monomeric silane coupling agent. The content of the monomeric silane coupling agent is less than 5.0 parts by mass relative to 100 parts by mass of the (meth)acrylic polymer.

2. The laminated body according to claim 1, wherein, The weight-average molecular weight (Mw) of the (meth)acrylic polymer is 1.5 million to 4 million.

3. The laminated body according to claim 1, wherein, The adhesive layer is formed from an adhesive comprising the (meth)acrylic polymer and a crosslinking agent. The adhesive has a gel fraction of over 85%.

4. The laminated body according to claim 1, wherein, The (meth)acrylic acid polymer contains 1 to 30% by mass of nitrogen-containing monomers as monomer units.

5. The laminated body according to claim 4, wherein, The nitrogen-containing monomer is a heterocyclic acrylic acid monomer.

6. The laminate according to claim 1, wherein, The (meth)acrylic acid polymer contains 0.5 to 20% by mass of acrylic acid as a monomer unit.

7. The laminated body according to claim 1, wherein, The void layer does not contain organic fluorine compounds.

8. The laminated body according to claim 1, wherein, Before and after a heating durability test at 65°C and 95% relative humidity for 500 hours, the change in refractive index of the porous layer satisfies the following mathematical formula (1): |n-n0| < 0.04 (1) In the mathematical formula (1), n is the refractive index of the void layer after the heat durability test. n0 is the refractive index of the void layer before the heat durability test.

9. The laminate according to claim 1, wherein, An intermediate layer exists between the void layer and the adhesive layer. The intermediate layer is formed by combining the void layer and the adhesive layer into one layer.

10. The laminate according to claim 9, wherein, The thickness of the intermediate layer is 10~100nm.

11. An optical component comprising a laminate according to any one of claims 1 to 10.

12. An optical device comprising the optical component of claim 11.

Images