Optical laminates

Abstract

The present invention provides an optical laminate that does not warp or peel at the interface between the resin layer and the release sheet (α), and can appropriately form a peeling starting point between the protective film (β) and the resin layer or other layers located on the resin layer. The optical laminate comprises a release sheet (α), an optical film, and a protective film (β), wherein the optical film comprises a resin layer located on one surface, the release sheet (α) is directly laminated on the resin layer, and the protective film (β) is laminated on the resin layer from the outermost surface of the other side of the optical film directly or via another layer, wherein the resin layer is a cured product of a curable composition containing a curable compound, and the peeling force A1 when the release sheet (α) is peeled from the resin layer at a low peeling speed of 0.3 m / min and the adhesive force A2 when the protective film (β) is peeled from the resin layer or the other layer at a low peeling speed of 0.3 m / min satisfy the relationship A1>A2.

Description

Technical Field

[0001] The present invention relates to a release sheet, an optical film, and an optical laminate having a protective film. Background Art

[0002] In recent years, gas barrier films have been widely used as substrate materials and sealing materials. Gas barrier films are required to have high gas barrier properties that inhibit the permeation of water vapor, oxygen, and other substances. Furthermore, they are also required to have high light transmittance, for example, to enable use as optical films without impairing the visibility of the object to which the gas barrier film is applied, such as an electronic device, or to maintain the lightweight nature of the object to which it is applied.

[0003] Based on this viewpoint, a method is known in which a curable composition containing a curable compound is applied to a support, the curable compound contained in the resulting coating layer is cured to form a thin resin layer, and a gas barrier layer made of an inorganic film or the like is formed directly on the resin layer or via another layer. This production method can produce a gas barrier film with a resin layer on one surface and a gas barrier layer on the other surface (Patent Document 1).

[0004] Hereinafter, the property of inhibiting the permeation of water vapor and oxygen is referred to as "gas barrier properties," a film having gas barrier properties is referred to as a "gas barrier film," and a laminate having gas barrier properties is referred to as a "gas barrier laminate." Furthermore, a film used for optical applications is referred to as an "optical film," and a laminate containing an optical film is referred to as an "optical laminate." The aforementioned light-transmitting gas barrier film is also an optical film, and a gas barrier laminate containing a light-transmitting gas barrier film is also an optical laminate.

[0005] In the industrial industry, optical films such as gas barrier films are often manufactured as long strips and then wound into rolls for storage and transportation. For example, in order to protect the gas barrier layer and improve the handling of the gas barrier film, such rolls are sometimes formed into gas barrier laminates with a protective film as the outermost layer on one side and a release sheet as the outermost layer on the other side.

[0006] For example, Patent Document 2 describes a gas barrier laminate having a substrate layer, a gas barrier layer, and a protective film, and describes in Examples a gas barrier laminate having a structure of protective film 2 / resin substrate layer / gas barrier layer / protective film 1 .

[0007] Prior art literature

[0008] Patent Literature

[0009] Patent Document 1: International Publication No. 2013 / 018602

[0010] Patent Document 2: International Publication No. 2018 / 181004 Summary of the Invention

[0011] Problems to be solved by the invention

[0012] The present inventors have come up with the idea of ​​providing a gas barrier laminate in which a resin layer formed from a cured product of a curable resin composition is located on the outermost surface on one side and a gas barrier layer is located on the outermost surface on the other side, by providing a release sheet (α) directly laminated on the resin layer and a protective film (β) directly laminated on the gas barrier layer.

[0013] The gas barrier laminate having the above-described structure can be used, for example, as follows. First, the protective film (β) is peeled off from the gas barrier layer, an adhesive layer is formed on the surface of the exposed gas barrier layer, and the gas barrier layer is bonded and fixed to the surface of an adherend using the adhesive layer. Thereafter, the release sheet (α) is peeled off from the resin layer, thereby attaching the gas barrier film to the adherend.

[0014] However, in a gas barrier laminate having the above-described structure, when the protective film (β) is peeled from the gas barrier layer, there is a risk that a peeling starting point may not be smoothly formed between the protective film (β) and the gas barrier layer, resulting in warping and peeling at the interface between the resin layer and the release sheet (α). This problem is not limited to gas barrier laminates but is also a common problem in optical laminates in which the optical film comprises a resin layer and other layers, and has a structure of release sheet (α) / resin layer / other layer / protective film (β), or in which the optical film consists solely of a resin layer, and has a structure of release sheet (α) / resin layer / protective film (β).

[0015] It should be noted that, similar to the gas barrier laminate of the above-described configuration, the gas barrier laminate of Patent Document 2 describes a method in which a protective film 1 is provided on the gas barrier layer and the protective film 1 is peeled off before the protective film 2. However, since the base layer of the gas barrier laminate described in Patent Document 2 is a layer formed of a thermoplastic resin, not a cured product of a curable composition, and the protective film has an adhesive, there is no problem of preventing peeling at the interface between the resin layer and the release sheet (α), which is a problem that exists in gas barrier laminates and optical laminates having the above-described configuration.

[0016] The present invention has been made in view of the above-mentioned problems, and an object thereof is to provide an optical laminate that does not cause warping or peeling at the interface between the resin layer and the release sheet (α), and can appropriately form a peeling starting point between the protective film (β) and the resin layer or other layers located on the resin layer.

[0017] Solutions to the Problem

[0018] The present inventors conducted intensive research to solve the above-mentioned problems and found that the above-mentioned problems can be solved by setting a given relationship between the peeling force and the adhesive force when peeling the release sheet (α) and the protective film (β) under given conditions, thereby completing the present invention.

[0019] That is, the present invention provides the following [1] to [9].

[0020] [1] An optical laminate comprising a release sheet (α), an optical film, and a protective film (β), wherein the optical film comprises a resin layer on the outermost surface on one side thereof,

[0021] The release sheet (α) is directly laminated on the resin layer.

[0022] The protective film (β) is laminated on the resin layer directly or via another layer from the outermost surface of the other side of the optical film.

[0023] The resin layer is a cured product of a curable composition containing a curable compound.

[0024] The peeling force A1 when the peeling sheet (α) is peeled off from the above-mentioned resin layer at a low peeling speed of 0.3 m / min, and the adhesive force A2 when the protective film (β) is peeled off from the above-mentioned resin layer or the above-mentioned other layer at a low peeling speed of 0.3 m / min satisfy the relationship A1>A2.

[0025] [2] The optical laminate according to [1], wherein the peeling force A1 is 500 mN / 50 mm or less.

[0026] [3] The optical laminate according to [1] or [2], wherein the protective film (β) has an adhesive layer and is releasably attached to the resin layer or the other layer via the adhesive layer.

[0027] [4] The optical laminate according to [3], wherein the pressure-sensitive adhesive layer comprises at least one of a polyolefin polymer and a polyolefin copolymer.

[0028] [5] The optical laminate according to any one of [1] to [4], wherein the resin layer is a cured product of a curable resin composition containing a polymer component (A) and a curable monomer (B).

[0029] [6] The optical laminate according to [5], wherein the polymer component (A) has a glass transition temperature (Tg) of 250°C or higher.

[0030] [7] An optical laminate as described in any one of [1] to [6] above, wherein the optical film includes a functional layer as the other layer, the functional layer is located on the outermost surface opposite to the outermost surface where the resin layer is located, the functional layer is a layer obtained by subjecting an inorganic film or a layer containing a polymer compound to a modification treatment, and the protective film (β) is directly laminated on the functional layer.

[0031] [8] The optical laminate according to any one of [1] to [6], wherein the optical film includes a gas barrier layer as the other layer, the gas barrier layer is located on the outermost surface opposite to the outermost surface where the resin layer is located, and the protective film (β) is directly laminated on the gas barrier layer.

[0032] [9] The optical laminate according to any one of [1] to [6], wherein the optical film includes a conductive layer as the other layer, the conductive layer is located on the outermost surface opposite to the outermost surface where the resin layer is located, and the protective film (β) is directly laminated on the conductive layer.

[0033] Effects of the Invention

[0034] According to the present invention, an optical laminate can be provided in which warping and peeling do not occur at the interface between the resin layer and the release sheet (α), and a peeling starting point can be appropriately formed between the protective film (β) and the resin layer or other layers located on the resin layer. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 It is a schematic cross-sectional view showing an example of a gas barrier laminate.

[0036] Figure 2 It is a schematic cross-sectional view showing an example of a rolled gas barrier laminate.

[0037] Figure 3 It is a schematic cross-sectional view showing another example of the rolled gas barrier laminate.

[0038] Figure 4 It is an explanatory diagram showing an example of a method for producing a gas barrier laminate.

[0039] Figure 5 This is an explanatory diagram showing an example of a method of using the gas barrier laminate.

[0040] Figure 6 The diagrams illustrate methods for measuring the peeling force and inspecting the appearance of a gas barrier laminate and an optical laminate.

[0041] Explanation of symbols

[0042] 1 peeling sheet (α)

[0043] 2 resin layer

[0044] 2a Curable resin layer

[0045] 3 Gas barrier layer (other layers)

[0046] 3a Gas barrier layer before curing

[0047] 4 Protective film (β)

[0048] 5 Adhesive layer

[0049] 10, 10A, 10B Gas barrier laminates (optical laminates)

[0050] 10A1, 10B1 roll part

[0051] 10A2, 10B2 extraction part

[0052] 10a Gas barrier film

[0053] 11 core material

[0054] 20 Adhesion

[0055] 30 Glass Panes

[0056] 40 PET film substrate DETAILED DESCRIPTION

[0057] Hereinafter, an optical laminate according to an embodiment of the present invention (hereinafter, also referred to as “the present embodiment” in some cases) will be described.

[0058] 1. Optical laminates

[0059] The optical laminate of an embodiment of the present invention includes a release sheet (α), an optical film and a protective film (β), wherein the optical film includes a resin layer located on the outermost surface of one side thereof, the release sheet (α) is directly laminated on the above-mentioned resin layer, and the protective film (β) is laminated on the above-mentioned resin layer directly or via other layers from the outermost surface side of the other side of the optical film, and the above-mentioned resin layer is a cured product of a curable composition containing a curable compound, and the peeling force A1 when the release sheet (α) is peeled off from the above-mentioned resin layer at a low peeling speed of 0.3 m / min and the adhesive force A2 when the protective film (β) is peeled off from the above-mentioned resin layer or the above-mentioned other layer at a low peeling speed of 0.3 m / min satisfy the relationship A1>A2.

[0060] It should be noted that the peel force A1 and the adhesive force A2 are the peel force and the adhesive force (mN / 50mm), respectively, when a 50mm wide protective film (β) or release sheet (α) of an optical laminate is peeled off at a peel angle of 180° and a peel speed of 0.3m / min using the method described in the Examples below. Furthermore, the peel force B1 and the adhesive force B2, described below, are the peel force and the adhesive force (mN / 50mm), respectively, measured in the same manner as above, except that the peel speed is set to 20m / min.

[0061] Hereinafter, a peeling speed of 0.3 m / min may be referred to as “low-speed peeling conditions”, and a peeling speed of 20 m / min may be referred to as “high-speed peeling conditions”.

[0062] In a laminate in which a resin layer, which is a cured product of a curable composition containing a curable compound, is located on the outermost surface of one side of an optical film, a release sheet (α) is directly laminated on the resin layer of the optical film, and a protective film (β) is laminated on the resin layer from the outermost surface side of the other side of the optical film directly or via another layer, by making the adhesive force A2 when the protective film (β) is peeled off from the outermost surface of the other side of the optical film or the other layer under low-speed peeling conditions and the peeling force A1 when the release sheet (α) is peeled off from the resin layer under low-speed peeling conditions satisfy the above-mentioned relationship, warping and peeling will not occur at the interface between the resin layer and the release sheet (α), and a portion (peeling starting point) that will become a peeling starting point can be easily formed between the protective film (β) and the resin layer or the other layer, thereby providing a gas barrier laminate in which only the protective film (β) can be well peeled while maintaining the close adhesion of the release sheet (α) to the resin layer.

[0063] When the above relationship is satisfied under low-speed peeling conditions, as long as the protective film (β) is peeled from the resin layer or other layers under low-speed peeling conditions, warping and peeling will not occur at the interface between the resin layer and the peeling sheet (α), and a peeling starting point can be appropriately formed between the protective film (β) and the resin layer or the other layers. Therefore, regardless of the relationship between the peeling forces when peeling the peeling sheet (α) from the resin layer and peeling the protective film (β) from the outermost surface of the other side of the optical film or the other layers under high-speed peeling conditions (for example, even when the relationship between the peeling forces is reversed under high-speed peeling conditions), after forming the peeling starting point of the protective film (β) under low-speed peeling conditions, the protective film (β) and the peeling sheet (α) can be peeled off under high-speed peeling conditions, thereby allowing the optical film to be attached to the target adherend with high productivity.

[0064] Figure 1 An example of a specific structure of a gas barrier laminate as one of the optical laminates according to the embodiment of the present invention is shown.

[0065] Figure 1 The gas barrier laminate 10 shown in the schematic cross-sectional view of FIG. 1 includes a gas barrier film 10 a , a release sheet 1 , and a protective film 4 .

[0066] The gas barrier film 10a includes a resin layer 2 located on the outermost surface on one side and a gas barrier layer 3 located on the outermost surface on the other side. A release sheet 1 is directly laminated on the surface of the resin layer 2 opposite the gas barrier layer 3. Furthermore, a protective film 4 is directly laminated on the surface of the gas barrier layer 3 opposite the resin layer 2. In other words, the protective film 4 is laminated on the outermost resin layer on one side of the gas barrier film 10a, which is one of the optical films, via the gas barrier layer 3 from the outermost surface of the other side of the gas barrier film 10a.

[0067] Figure 1 The peeling sheet 1 is equivalent to the peeling sheet (α) described above. Figure 1 The protective film 4 corresponds to the above-mentioned protective film (β).

[0068] As will be described later, finally, a layer derived from the gas barrier film 10 a is formed on the adherend in a state where the protective film 4 and the release sheet 1 are peeled and removed.

[0069] The thickness of the optical laminate can be appropriately determined depending on the intended use of the electronic device, etc. From the viewpoint of handleability, the substantial thickness of the optical laminate according to the embodiment of the present invention is preferably 0.3 to 50 μm, more preferably 0.5 to 25 μm, and even more preferably 0.7 to 12 μm.

[0070] It should be noted that the "substantial thickness" refers to the thickness in the state of use. That is, although the optical laminate comprises a release sheet (α) and a protective film (β), the thickness of the release sheet (α) and the protective film (β) that are removed during use is not included in the "substantial thickness."

[0071] As will be described later, the resin layer can be formed thinly using a coating method, etc. As the thickness of the optical laminate is reduced, the bending resistance of the optical film after being attached to an adherend can be further improved.

[0072] The optical laminate according to an embodiment of the present invention comprises a resin layer positioned on one outermost surface. By adjusting the materials, thicknesses, and formation methods of this resin layer and other layers, a material having excellent heat resistance and interlayer adhesion, low birefringence, and excellent optical isotropy can be obtained. In the case of a gas barrier laminate having a gas barrier layer in addition to the resin layer, as in the aforementioned gas barrier laminate, by adjusting the materials, thicknesses, and formation methods of each layer, a material having excellent heat resistance, interlayer adhesion, and gas barrier properties, low birefringence, and excellent optical isotropy can be obtained.

[0073] 1-1. Relationship between Adhesive Strength of Protective Film (β) and Release Strength of Release Sheet (α)

[0074] As described above, the adhesive force A2 when the protective film (β) is peeled off from the resin layer of the optical film or another layer located on the resin layer at a low peeling speed of 0.3 m / min, and the peeling force A1 when the release sheet (α) is peeled off from the resin layer at a low peeling speed of 0.3 m / min satisfy the relationship A1>A2. From the viewpoint of more easily forming the peeling starting point of the protective film (β), A1 is preferably ≥1.2×A2, more preferably A1≥1.5×A2, and even more preferably A1≥2.0×A2. From the viewpoint of not excessively reducing productivity, A1 is preferably ≤20×A2, more preferably A1≤10×A2, and even more preferably A1≤5×A2.

[0075] The relationship A1>A2 in the optical laminate can be achieved by increasing the peeling force of the release sheet (α) relative to the resin layer, and the peeling force of the release sheet (α) relative to the resin layer can be increased by, for example, moderately weakening the adhesive force of the adhesive layer formed on the surface of the outermost side of the protective film (β) described later, which is formed on the other side of the optical film, or by appropriately selecting the material and surface shape of the release sheet (α), or appropriately selecting the material and manufacturing method of the resin layer.

[0076] There is no special restriction on the relationship between the adhesive force B2 when the protective film (β) is peeled off from the above-mentioned resin layer or the above-mentioned other layer at a high-speed peeling condition of 20 m / min and the peeling force B1 when the peeling sheet (α) is peeled off from the resin layer at a high-speed peeling condition of 20 m / min. It can be B1>B2, B1=B2, or B1<B2.

[0077] For the optical laminate of the embodiment of the present invention, since the protective film (β) can be properly peeled off under low-speed peeling conditions, it is not necessary to have a relationship of B1>B2 when high-speed peeling conditions are adopted to improve productivity. That is, it can also be B1≤B2. Among them, from the viewpoint of preventing the breakage of the optical laminate during high-speed peeling, it is preferably 10×B1≥B2≥B1, more preferably 6.0×B1≥B2≥B1, and further preferably 4.5×B1≥B2≥B1. In the case where the protective film (β) has an adhesive layer, there is a tendency for the value of B2 to be greater than A2, and therefore it tends to reach B1≤B2. Even in this case, as long as the relationship A1>A2 is maintained as described above, the protective film (β) can be properly peeled off at any stage of the low-speed peeling at the peeling starting point and the high-speed peeling thereafter.

[0078] 1-2. Adhesion of the protective film (β) to the resin layer or other layers

[0079] From the viewpoint of making it easier to form the peeling starting point of the protective film (β), the adhesive force A2 when the protective film (β) is peeled off from the resin layer of the optical film or other layers on the resin layer at a low speed of 0.3 m / min is preferably 100 mN / 50 mm or less, more preferably 85 mN / 50 mm or less, and further preferably 70 mN / 50 mm or less. In addition, from the viewpoint of making it easier to stably adhere the protective film (β) to the above-mentioned resin layer or other layers during storage and transportation of the optical laminate, it is preferably 15 mN / 50 mm or more, and more preferably 30 mN / 50 mm or more.

[0080] From the viewpoint of preventing breakage of the optical laminate during high-speed peeling, the adhesive force B2 when the protective film (β) is peeled from the above-mentioned resin layer or the above-mentioned other layer at a high-speed peeling condition of 20 m / min is preferably 50 to 2000 mN / 50 mm, more preferably 100 to 1000 mN / 50 mm.

[0081] The adhesive strengths A2 and B2 can be adjusted to fall within the above numerical ranges by, for example, appropriately weakening the adhesive strength of the pressure-sensitive adhesive layer formed on the outermost surface of the other optical film of the protective film (β) described below.

[0082] 1-3. Peeling force of release sheet (α) relative to resin layer

[0083] From the viewpoint of avoiding excessive stress on the resin layer when peeling the release sheet (α) and preventing cracks from occurring in other layers such as a gas barrier layer when the release sheet (α) is present, the peeling force A1 when the release sheet (α) is peeled from the resin layer at a low peeling speed of 0.3 m / min is preferably 500 mN / 50 mm or less, more preferably 300 mN / 50 mm or less, and further preferably 200 mN / 50 mm or less. Furthermore, from the viewpoint of easily making the release sheet (α) stably adhere to the resin layer, the peeling force A1 is preferably 40 mN / 50 mm or more, more preferably 60 mN / 50 mm or more, and further preferably 80 mN / 50 mm or more.

[0084] In addition, from the viewpoint of easily ensuring the adhesion of the release sheet (α) to the resin layer without causing an excessive decrease in productivity, the peeling force B1 when the release sheet (α) is peeled from the resin layer at a high-speed peeling condition of 20 m / min is preferably 40 to 500 mN / 50 mm, more preferably 60 to 300 mN / 50 mm, and even more preferably 80 to 200 mN / 50 mm.

[0085] In order to make the values ​​of the peeling forces A1 and B1 within the above-mentioned numerical range, this can be achieved by, for example, appropriately selecting the material and surface shape of the release sheet (α).

[0086] 1-4. Optical films

[0087] The optical film includes at least a resin layer located on the outermost surface of one side of the optical film. The optical film may be composed of only the resin layer or may be composed of the resin layer and other layers.

[0088] The other layer is located on the outermost surface opposite to the outermost surface where the resin layer is located in the optical film, and the protective film (β) is directly laminated on the other layer.

[0089] Examples of the aforementioned other layers include: (i) functional layers obtained by modifying a layer comprising an inorganic film or a polymer compound, (ii) gas barrier layers, and (iii) conductive layers. When the optical film comprises a resin layer and a gas barrier layer, the optical film becomes a gas barrier film, and the optical laminate becomes a gas barrier laminate. Furthermore, when the optical film comprises a resin layer and a transparent conductive layer, the optical film becomes a transparent conductive film, and the optical laminate becomes a transparent electrode-forming laminate.

[0090] The other layers and the resin layer may be directly laminated together, or may be laminated together with another layer interposed therebetween.

[0091] A plurality of sets of resin layers and the other layers may be stacked. In this case, another layer may be further present between at least any one of the plurality of sets of resin layers and the other layers.

[0092] When the optical film is a gas barrier film, the water vapor transmission rate of the gas barrier film in an atmosphere at 40°C and a relative humidity of 90% is generally 1.0×10 -2 g / m 2 / day or less, preferably 8.0×10 -3 g / m 2 / day or less, more preferably 6.0×10 -3 g / m 2 / day or less.

[0093] 1-5. Resin layer

[0094] The resin layer of the optical film included in the optical laminate according to an embodiment of the present invention is formed from a cured product of a curable composition containing a curable compound, preferably a cured product of a curable resin composition containing a polymer component (A) and a curable monomer (B). The resin layer may be a single layer or may include multiple layers stacked together.

[0095] [Polymer component (A)]

[0096] The polymer component (A) is not particularly limited, but preferably has a glass transition temperature (Tg) of 250°C or higher, more preferably 290°C or higher, and even more preferably 320°C or higher. By using a polymer component (A) having a Tg of 250°C or higher, an optical laminate having sufficiently excellent heat resistance can be easily obtained.

[0097] Here, Tg refers to the temperature at which tan δ (loss modulus / storage modulus) obtained by viscoelasticity measurement (measurement in a tensile mode at a frequency of 11 Hz and a heating rate of 3°C / min in the range of 0 to 250°C) reaches its maximum value.

[0098] Since the resin layer of the optical laminate according to the embodiment of the present invention is composed of a cured product of a curable resin composition containing a polymer component (A) having a Tg of 250° C. or higher, the resin layer exhibits very excellent heat resistance, thereby obtaining an optical laminate having excellent heat resistance.

[0099] When the heat resistance of the resin layer is high, the elastic modulus at high temperature increases and the resin layer is less likely to shrink by heat. As a result, when the optical film has other layers such as a gas barrier layer, fine cracks can be avoided in the other layers. Therefore, for example, when the above-mentioned other layer is a gas barrier layer, its gas barrier properties can be prevented from decreasing. In addition, when the above-mentioned other layer is a conductive layer, its conductivity can be prevented from decreasing. Furthermore, when the peeling force A1 when the peeling sheet (α) is peeled off from the above-mentioned resin layer or the above-mentioned other layer at a low speed of 0.3m / min is 500mN / 50mm or less, from the perspectives of heat resistance and preventing the resin layer from being deformed when the peeling sheet (α) is peeled off, cracks in the above-mentioned other layer can be prevented, and thus it is preferred. In addition, when the above-mentioned other layer is a conductive layer, by making the heat resistance of the resin layer high, it is easy to prevent the resin layer from being affected by heating such as annealing and deforming when the conductive layer is formed.

[0100] The weight average molecular weight (Mw) of the polymer component (A) is generally in the range of 100,000 to 3,000,000, preferably 200,000 to 2,000,000, and more preferably 500,000 to 1,000,000. Furthermore, the molecular weight distribution (Mw / Mn) is preferably in the range of 1.0 to 5.0, and more preferably 2.0 to 4.5. The weight average molecular weight (Mw) and the molecular weight distribution (Mw / Mn) are values ​​calculated as polystyrene as measured by gel permeation chromatography (GPC). By setting Mw to 100,000 or more, the elongation at break of the resin layer can be easily increased.

[0101] As polymer component (A), preferably a thermoplastic resin, more preferably an amorphous thermoplastic resin. By using an amorphous thermoplastic resin, it is easy to obtain a resin layer with excellent optical isotropy, and it is easy to obtain an optical laminate with excellent transparency. In addition, amorphous thermoplastic resins are generally easily soluble in organic solvents, and therefore can be formed into a resin layer efficiently by a solution casting method as described later.

[0102] Here, the amorphous thermoplastic resin refers to a thermoplastic resin whose melting point is not observed in differential scanning calorimetry.

[0103] It is particularly preferred that the polymer component (A) be soluble in a low-boiling-point general-purpose organic solvent such as benzene or methyl ethyl ketone (MEK). When the polymer component (A) is soluble in a general-purpose organic solvent, it is easy to form a resin layer by coating.

[0104] As the polymer component (A), an amorphous thermoplastic resin having a Tg of 250° C. or higher and soluble in a low-boiling-point general-purpose organic solvent such as benzene or MEK is particularly preferred.

[0105] Furthermore, from the viewpoint of heat resistance, the polymer component (A) is preferably a thermoplastic resin having a ring structure such as an aromatic ring structure or an alicyclic structure, and more preferably a thermoplastic resin having an aromatic ring structure.

[0106] Specific examples of the polymer component (A) include polyimide resins and polyarylate resins having a Tg of 250°C or higher. These resins generally have excellent heat resistance and are amorphous thermoplastic resins, making them suitable for forming coating films by solution casting. Among these resins, polyimide resins are preferred because they have a high Tg, excellent heat resistance, and are readily available as components that exhibit good heat resistance and are soluble in general organic solvents.

[0107] The polyimide resin is not particularly limited as long as the effects of the present invention are not impaired, and examples thereof include aromatic polyimide resins, aromatic (carboxylic acid component)-cycloaliphatic (diamine component) polyimide resins, cycloaliphatic (carboxylic acid component)-aromatic (diamine component) polyimide resins, cycloaliphatic polyimide resins, and fluorinated aromatic polyimide resins. Polyimide resins having a fluorine group in the molecule are particularly preferred.

[0108] The polyimide resin is preferably soluble in a low-boiling-point organic solvent such as benzene or methyl ethyl ketone. It is particularly preferably soluble in methyl ethyl ketone. When soluble in methyl ethyl ketone, a layer of the curable resin composition can be easily formed by coating and drying.

[0109] Fluorine-containing polyimide resins are particularly preferred from the viewpoint of being easily soluble in low-boiling-point general-purpose organic solvents such as methyl ethyl ketone and readily forming a resin layer by coating. Fluorine-containing polyimide resins are preferably aromatic polyimide resins having fluorine groups.

[0110] As the aromatic polyimide resin having a fluorine group, a polyimide resin having a skeleton represented by the following chemical formula in its molecule is preferable.

[0111] [Chemical Formula 1]

[0112]

[0113] The polyimide resin having the skeleton shown in the above chemical formula has an extremely high Tg of over 300°C due to the high rigidity of the above skeleton. As a result, the heat resistance of the resin layer can be greatly improved. In addition, the above skeleton is linear and has high flexibility, which makes it easy to improve the elongation at break of the resin layer. Furthermore, the polyimide resin having the above skeleton can be dissolved in general organic solvents with low boiling points such as methyl ethyl ketone due to the presence of a fluorine group. Therefore, a solution casting method can be used for coating to form a resin layer in the form of a coating film, and the solvent can also be easily removed by drying. The polyimide resin having the skeleton shown in the above chemical formula can be obtained by using 2,2'-bis(trifluoromethyl)-4,4'-diaminobiphenyl and 4,4'-(1,1,1,3,3,3-hexafluoropropane-2,2-diyl)diphthalic dianhydride and through the polymerization and imidization reaction of the above-mentioned polyamic acid.

[0114] The polymer component (A) may be used alone or in combination of two or more. Furthermore, the polymer component (A) may be used in combination with a polymer component (A') having a glass transition temperature of less than 250°C. Examples of the polymer component (A') include polyamide resins and polyarylate resins having a Tg of less than 250°C, with polyamide resins being preferred.

[0115] [Curable Monomer (B)]

[0116] The curable monomer (B) is a monomer having a polymerizable unsaturated bond and capable of participating in a polymerization reaction or a polymerization reaction and a crosslinking reaction. It should be noted that, in this specification, the term "curing" is a broad concept encompassing "polymerization of a monomer" or "polymerization of a monomer followed by a crosslinking reaction of a polymer." The use of the curable monomer (B) can yield an optical laminate with excellent solvent resistance.

[0117] By using a resin layer formed from a cured product of a curable resin composition containing the polymer component (A) and the curable monomer (B), a thin resin layer with excellent heat resistance can be easily formed. In addition, when such a material is used, optical problems caused by materials having anisotropic molecular orientation, such as polyester films, which are commonly used as substrates for optical laminates, are less likely to occur.

[0118] The molecular weight of the curable monomer (B) is usually 3,000 or less, preferably 200 to 2,000, and more preferably 200 to 1,000.

[0119] The number of polymerizable unsaturated bonds in the curable monomer (B) is not particularly limited. The curable monomer (B) may be a monofunctional monomer having one polymerizable unsaturated bond, but preferably contains at least one or more polyfunctional monomers such as bifunctional and trifunctional monomers having multiple polymerizable unsaturated bonds.

[0120] Examples of the monofunctional monomer include monofunctional (meth)acrylic acid derivatives.

[0121] The monofunctional (meth)acrylic acid derivative is not particularly limited as long as it is a compound having one (meth)acryloyl group in the molecule, and a known compound can be used.

[0122] Examples of the polyfunctional monomer include polyfunctional (meth)acrylic acid derivatives.

[0123] The polyfunctional (meth)acrylic acid derivative is not particularly limited as long as it has two or more (meth)acryloyl groups in the molecule, and known compounds can be used. Examples thereof include di- to hexafunctional (meth)acrylic acid derivatives.

[0124] Examples of the bifunctional (meth)acrylic acid derivative include compounds represented by the following formula.

[0125] [Chemical Formula 2]

[0126]

[0127] Where R 1 Means the same as above, R 2 represents a divalent organic group. 2 Examples of the divalent organic group include groups represented by the following formulae.

[0128] [Chemical Formula 3]

[0129] -O-(CH2) s -O-

[0130] -O(CH2CH2O)t -

[0131] (In the formula, s represents an integer of 1 to 20, t represents an integer of 1 to 30, u and v each independently represent an integer of 1 to 30, and "-" at both ends represents a bonding position.)

[0132] Specific examples of the bifunctional (meth) acrylic acid derivatives represented by the above formula include tricyclodecane dimethanol di(meth)acrylate, polyethylene glycol di(meth)acrylate, propoxylated ethoxylated bisphenol A di(meth)acrylate, ethoxylated bisphenol A di(meth)acrylate, 1,10-decanediol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, 9,9-bis[4-(2-acryloyloxyethoxy)phenyl]fluorene, etc. Among these compounds, tricyclodecane dimethanol di(meth)acrylate and the like are preferred from the viewpoint of heat resistance and toughness. 7 The compound having a tricyclodecane skeleton as a divalent organic group, propoxylated ethoxylated bisphenol A di(meth)acrylate, ethoxylated bisphenol A di(meth)acrylate, etc. wherein R 7 The compound having a bisphenol skeleton, 9,9-bis[4-(2-acryloyloxyethoxy)phenyl]fluorene, etc. wherein R 7 The divalent organic group shown is a compound having a 9,9-bisphenylfluorene skeleton.

[0133] In addition, examples of bifunctional (meth)acrylic acid derivatives other than the above include neopentyl glycol adipate di(meth)acrylate, hydroxypivalate neopentyl glycol di(meth)acrylate, caprolactone-modified dicyclopentenyl di(meth)acrylate, ethylene oxide-modified phosphate di(meth)acrylate, di(acryloyloxyethyl)isocyanurate, and allylated cyclohexyl di(meth)acrylate.

[0134] Examples of the trifunctional (meth)acrylic acid derivative include trimethylolpropane tri(meth)acrylate, pentaerythritol tri(meth)acrylate, propionic acid-modified dipentaerythritol tri(meth)acrylate, propylene oxide-modified trimethylolpropane tri(meth)acrylate, and tris(acryloyloxyethyl)isocyanurate.

[0135] Examples of the tetrafunctional (meth)acrylic acid derivative include pentaerythritol tetra(meth)acrylate and the like.

[0136] Examples of the pentafunctional (meth)acrylic acid derivative include propionic acid-modified dipentaerythritol penta(meth)acrylate.

[0137] Examples of the hexafunctional (meth)acrylic acid derivative include dipentaerythritol hexa(meth)acrylate and caprolactone-modified dipentaerythritol hexa(meth)acrylate.

[0138] As the curable monomer (B), a cyclopolymerizable monomer can also be used. A cyclopolymerizable monomer refers to a monomer having the property of undergoing free radical polymerization while undergoing cyclization. Examples of the cyclopolymerizable monomer include non-conjugated dienes, for example, α-allyloxymethyl acrylic acid monomers, preferably alkyl esters of 2-allyloxymethyl acrylic acid having 1 to 4 carbon atoms, cyclohexyl 2-(allyloxymethyl)acrylate, more preferably alkyl esters of 2-allyloxymethyl acrylic acid having 1 to 4 carbon atoms, and even more preferably methyl 2-(allyloxymethyl)acrylate.

[0139] In addition, cyclopolymerizable monomers such as dimethyl 2,2'-[oxybis(methylene)]bis-2-propionate, diethyl 2,2'-[oxybis(methylene)]bis-2-propionate, di(n-propyl) 2,2'-[oxybis(methylene)]bis-2-propionate, di(isopropyl) 2,2'-[oxybis(methylene)]bis-2-propionate, di(n-butyl) 2,2'-[oxybis(methylene)]bis-2-propionate, di(n-hexyl) 2,2'-[oxybis(methylene)]bis-2-propionate, and dicyclohexyl 2,2'-[oxybis(methylene)]bis-2-propionate can also be used.

[0140] The curable monomer (B) can be used alone or in combination of two or more.

[0141] Among these monomers, the curable monomer (B) is preferably a polyfunctional monomer from the viewpoint of obtaining a resin layer with better heat resistance and solvent resistance. As the polyfunctional monomer, a bifunctional (meth)acrylic acid derivative is preferred from the viewpoint of being easily mixed with the polymer component (A), being less likely to cause curing shrinkage of the polymer, and being able to suppress curling of the cured product.

[0142] As the curable monomer (B), it is more preferable to include a polyfunctional (meth)acrylate compound and a cyclopolymerizable monomer. By using them in combination, it is easy to adjust the heat resistance of the resin layer to an appropriate level and the elongation at break of the resin layer to the above range.

[0143] When the curable monomer (B) contains a multifunctional monomer, the content thereof is preferably 40% by mass or more, more preferably 50 to 100% by mass, based on the total amount of the curable monomer (B).

[0144] [Curable resin composition]

[0145] The curable resin composition for forming the resin layer according to the embodiment of the present invention can be prepared by mixing the polymer component (A), the curable monomer (B), and, if necessary, the polymerization initiator described below and other components, and dissolving or dispersing them in an appropriate solvent.

[0146] The total content of the polymer component (A) and the curable component (B) in the curable resin composition is preferably 40 to 99.5% by mass, more preferably 60 to 99% by mass, and even more preferably 80 to 98% by mass, relative to the total mass of the curable resin composition excluding the solvent.

[0147] The content of the polymer component (A) and the curable monomer (B) in the curable resin composition is preferably polymer component (A):curable monomer (B) = 30:70 to 90:10, more preferably 35:65 to 80:20, in terms of the mass ratio of the polymer component (A) to the curable monomer (B).

[0148] In the curable resin composition, by adjusting the mass ratio of the polymer component (A):the curable monomer (B) within such a range, the flexibility of the resulting resin layer tends to be further improved, and the solvent resistance of the resin layer tends to be maintained.

[0149] In addition, when the content of the curable monomer (B) in the curable resin composition is within the above range, for example, when a resin layer is obtained by a solution casting method, the solvent can be removed efficiently, thereby eliminating problems of deformation such as curling and waving caused by a prolonged drying process.

[0150] When using a combination of multiple resins having different solvent solubilities as the polymer component (A), such as a combination of the above-mentioned polyimide resin and a polyamide resin or a polyarylate resin, it is preferred to first dissolve the resins in a solvent suitable for each, and then add a solution containing the other resins to the low-boiling-point organic solvent containing the resins.

[0151] The curable resin composition may contain a polymerization initiator as needed. The polymerization initiator can be used without particular limitation as long as it is a component that initiates a curing reaction, and examples thereof include thermal polymerization initiators and photopolymerization initiators.

[0152] Examples of thermal polymerization initiators include organic peroxides and azo compounds. Examples of photopolymerization initiators include alkylphenone-based photopolymerization initiators, phosphorus-based photopolymerization initiators, titanocene-based photopolymerization initiators, oxime ester-based photopolymerization initiators, benzophenone-based photopolymerization initiators, and thioxanthone-based photopolymerization initiators. Phosphorus-based photopolymerization initiators are preferred.

[0153] When the polymer component (A) is a thermoplastic resin having an aromatic ring, the polymer component (A) absorbs ultraviolet light, which may hinder the curing reaction. However, by using the phosphorus-based photopolymerization initiator described above, the curing reaction can be efficiently carried out using light of a wavelength not absorbed by the polymer component (A).

[0154] The polymerization initiators may be used alone or in combination of two or more.

[0155] The content of the polymerization initiator is preferably 0.05 to 15% by mass, more preferably 0.05 to 10% by mass, and even more preferably 0.05 to 5% by mass, relative to the total mass of the curable resin composition excluding the solvent.

[0156] Furthermore, the curable resin composition may contain a photopolymerization initiation auxiliary such as triisopropanolamine or 4,4'-diethylaminobenzophenone in addition to the polymer component (A), the curable monomer (B), and the polymerization initiator.

[0157] The solvent used for preparing the curable resin composition is not particularly limited, and examples thereof include: aliphatic hydrocarbon solvents such as n-hexane and n-heptane; aromatic hydrocarbon solvents such as toluene and xylene; halogenated hydrocarbon solvents such as dichloromethane, vinyl chloride, chloroform, carbon tetrachloride, 1,2-dichloroethane, and monochlorobenzene; alcohol solvents such as methanol, ethanol, propanol, butanol, and propylene glycol monomethyl ether; ketone solvents such as acetone, methyl ethyl ketone, 2-pentanone, isophorone, and cyclohexanone; ester solvents such as ethyl acetate and butyl acetate; cellosolve solvents such as ethyl cellosolve; ether solvents such as 1,3-dioxolane, and the like.

[0158] The content of the solvent in the curable resin composition is not particularly limited, but is generally 0.1 to 1000 parts by mass, preferably 1 to 100 parts by mass, relative to 1 part by mass of the polymer component (A). The viscosity of the curable resin composition can be adjusted to an appropriate value by appropriately adjusting the amount of the solvent.

[0159] Furthermore, the curable resin composition may further contain known additives such as a plasticizer, an antioxidant, and an ultraviolet absorber within a range that does not impair the objects and effects of the present invention.

[0160] The method for curing the curable resin composition can be appropriately determined according to the types of the polymerization initiator and curable monomer used. Details will be described later in the section on the method for producing the optical laminate.

[0161] [Properties of the resin layer, etc.]

[0162] The thickness of the resin layer is not particularly limited and may be determined according to the purpose of the optical laminate. The thickness of the resin layer is usually 0.1 to 300 μm, preferably 0.1 to 100 μm, more preferably 0.1 to 50 μm, further preferably 0.1 to 10 μm, and particularly preferably 0.2 to 10 μm.

[0163] When the resin layer has a thickness of, for example, approximately 0.1 to 10 μm, the thickness of the optical laminate can be prevented from increasing, thereby achieving a thin optical laminate. A thin optical laminate is preferred because it does not increase the overall thickness of the device being used, such as in applications requiring thinner organic EL displays. Furthermore, a thin optical laminate improves the flexibility and bending resistance of the optical laminate after installation.

[0164] The resin layer exhibits excellent solvent resistance. Due to this excellent solvent resistance, even when an organic solvent is used to form another layer on the surface of the resin layer, the resin layer surface is substantially not dissolved. Therefore, even when a gas barrier layer, a conductive layer, or other layers are formed on the surface of the resin layer using a resin solution containing an organic solvent, the components of the resin layer are unlikely to mix into these layers, thereby minimizing the risk of degradation of gas barrier properties and conductivity.

[0165] The resin layer has excellent interlayer adhesion with other layers such as the gas barrier layer and the conductive layer. That is, the functional layer, gas barrier layer, or conductive layer can be formed on the resin layer without providing an anchor coat.

[0166] The resin layer is preferably colorless and transparent. By making the resin layer colorless and transparent, the optical laminate according to the embodiment of the present invention can be preferably used for optical applications.

[0167] As for the resin layer, as described above, it can be made to have heat resistance, solvent resistance, interlayer adhesion, transparency, and can make its birefringence low and optical isotropy excellent. Therefore, as described later, by forming a gas barrier layer, a conductive layer, etc. on the resin layer with such characteristics by, for example, a solution casting method, the functional layer can be made to show excellent gas barrier properties, excellent conductivity, and it is also possible to prevent the gas barrier properties and conductivity from being damaged by at least one of the heat resistance and solvent resistance of the resin layer. In addition, the heat resistance, interlayer adhesion, and transparency of the obtained optical laminate can be made excellent. In addition, an optical laminate with low birefringence and excellent optical isotropy can be obtained.

[0168] 1-6. Gas barrier layer

[0169] The gas barrier layer of the gas barrier laminate according to the embodiments of the present invention is not particularly limited in material, as long as it has gas barrier properties. Examples thereof include a gas barrier layer formed from an inorganic film, a gas barrier layer containing a gas barrier resin, and a gas barrier layer obtained by subjecting a layer containing a polymer compound to a modification treatment.

[0170] Among these, a gas barrier layer formed of an inorganic film and a gas barrier layer obtained by modifying a layer containing a polymer compound are preferred because a thin layer having excellent gas barrier properties and solvent resistance can be efficiently formed.

[0171] It should be noted that the aforementioned gas barrier layer formed of an inorganic film is, in other words, a functional layer formed of an inorganic film having gas barrier properties, and the aforementioned gas barrier layer obtained by subjecting the layer containing a polymer compound to a modification treatment is, in other words, a functional layer obtained by subjecting the layer containing a polymer compound to a modification treatment having gas barrier properties. In cases where the optical laminate is used for applications where gas barrier properties are not required or are less required, the aforementioned functional layer formed of an inorganic film or the functional layer obtained by subjecting the layer containing a polymer compound to a modification treatment may be a layer lacking gas barrier properties.

[0172] The inorganic film is not particularly limited, and examples thereof include inorganic vapor-deposited films.

[0173] Examples of the inorganic vapor-deposited film include vapor-deposited films of inorganic compounds and metals.

[0174] Examples of raw materials for the vapor-deposited film of inorganic compounds include: inorganic oxides such as silicon oxide, aluminum oxide, magnesium oxide, zinc oxide, indium oxide, and tin oxide; inorganic nitrides such as silicon nitride, aluminum nitride, and titanium nitride; inorganic carbides; inorganic sulfides; inorganic nitrogen oxides such as silicon oxynitride; inorganic carbon oxides; inorganic carbonitrides; and inorganic carbonitride oxides.

[0175] Examples of raw materials for the metal vapor-deposited film include aluminum, magnesium, zinc, and tin.

[0176] These materials may be used alone or in combination of two or more.

[0177] Among these, inorganic vapor-deposited films made of inorganic oxides, inorganic nitrides, or metals are preferred from the perspective of gas barrier properties, and inorganic vapor-deposited films made of inorganic oxides or inorganic nitrides are preferred from the perspective of transparency. The inorganic vapor-deposited film may be a single layer or a multilayer.

[0178] From the viewpoint of gas barrier properties and handleability, the thickness of the inorganic vapor-deposited film is preferably in the range of 10 to 2000 nm, more preferably 20 to 1000 nm, more preferably 30 to 500 nm, and even more preferably 40 to 200 nm.

[0179] Examples of methods for forming an inorganic vapor-deposited film include PVD (physical vapor deposition) methods such as vacuum deposition, sputtering, and ion plating, and CVD methods such as thermal CVD (chemical vapor deposition), plasma CVD, and photo-CVD.

[0180] Examples of the gas barrier resin used in the gas barrier layer include resins that are less permeable to oxygen, such as polyvinyl alcohol, partially saponified products thereof, ethylene-vinyl alcohol copolymers, polyacrylonitrile, polyvinyl chloride, polyvinylidene chloride, and polychlorotrifluoroethylene.

[0181] From the viewpoint of gas barrier properties, the thickness of the gas barrier layer composed of the gas barrier resin is preferably in the range of 10 to 2000 nm, more preferably 20 to 1000 nm, more preferably 30 to 500 nm, and even more preferably 40 to 200 nm.

[0182] Examples of a method for forming a gas barrier layer containing a gas barrier resin include a method of applying a solution containing the gas barrier resin on the resin layer and appropriately drying the resulting coating film.

[0183] In the gas barrier layer obtained by subjecting a layer containing a polymer compound (hereinafter also referred to as "polymer layer") to a modification treatment, examples of the polymer compound used include silicon-containing polymer compounds, polyimides, polyamides, polyamideimides, polyphenylene ethers, polyetherketones, polyetheretherketones, polyolefins, polyesters, polycarbonates, polysulfones, polyethersulfones, polyphenylene sulfides, polyarylates, acrylic resins, cycloolefin polymers, aromatic polymers, etc. These polymer compounds can be used alone or in combination of two or more.

[0184] Among them, the polymer compound is preferably a silicon-containing polymer compound. Examples of the silicon-containing polymer compound include polysilazane compounds (see Japanese Patent Publication No. 63-16325, Japanese Patent Publication No. 62-195024, Japanese Patent Publication No. 63-81122, Japanese Patent Publication No. 1-138108, Japanese Patent Publication No. 2-84437, Japanese Patent Publication No. 2-175726, Japanese Patent Publication No. 4-63833, Japanese Patent Publication No. 5-238827, Japanese Patent Publication No. 5-3 45826, Japanese Patent Application Laid-Open No. 2005-36089, Japanese Patent Application Laid-Open No. 6-122852, Japanese Patent Application Laid-Open No. 6-299118, Japanese Patent Application Laid-Open No. 6-306329, Japanese Patent Application Laid-Open No. 9-31333, Japanese Patent Application Laid-Open No. 10-245436, Japanese Patent Application No. 2003-514822, International Publication No. WO2011 / 107018, etc.), polycarbosilane compounds (see Journal of Materials Science, 2569-2576, Vol. 13, 1978, Organometallics, 1336-1344, Vol. 10, 1991, Journal of Organometallic Chemistry, 1-10, Vol. 521, 1996, Japanese Patent Application Publication No. 51-126300, Japanese Patent Application Publication No. 2001-328991, Japanese Patent Application Publication No. 2006-117917, Japanese Patent Application Publication No. 2009-286891, Japanese Patent Application Publication No. 2010-106100, etc.), polysilane compounds (see R. D. Miller, J. Michl; Chemical Review, Vol. 89, p. 1359 (1989), N. Matsumoto; Japanese Journal of Physics, Vol. 37, p. 5425 (1998), Japanese Patent Application Publication No. 2008-63586, Japanese Patent Application Publication No. 2009-235358, etc.), and polyorganosiloxane compounds (see Japanese Patent Application Publication No. 2010-229445, Japanese Patent Application Publication No. 2010-232569, Japanese Patent Application Publication No. 2010-238736, etc.).

[0185] Among them, polysilazane compounds are preferred from the perspective of being able to form a gas barrier layer with excellent gas barrier properties. Examples of polysilazane compounds include inorganic polysilazanes and organic polysilazanes. Examples of inorganic polysilazanes include perhydropolysilazanes, and examples of organic polysilazanes include compounds in which some or all of the hydrogen atoms of perhydropolysilazanes are substituted with organic groups such as alkyl groups. Among them, inorganic polysilazanes are more preferred from the perspective of ease of acquisition and the ability to form a gas barrier layer with excellent gas barrier properties.

[0186] Furthermore, as the polysilazane compound, a commercially available product as a glass coating material or the like may be used as it is.

[0187] The polysilazane compounds may be used alone or in combination of two or more.

[0188] In addition to the above-mentioned polymer compounds, the polymer layer may contain other components within the range not hindering the purpose of the present invention. Examples of other components include curing agents, other polymers, antioxidants, light stabilizers, flame retardants, and the like.

[0189] From the viewpoint of forming a gas barrier layer having excellent gas barrier properties, the content of the polymer compound in the polymer layer is preferably 50% by mass or more, more preferably 70% by mass or more.

[0190] As a method for forming a polymer layer, for example, a method of forming a polymer layer is mentioned, in which a layer-forming solution containing at least one polymer compound, other components used as needed, and a solvent is applied to a resin layer or a primer layer formed on the resin layer as needed by a known method, and the obtained coating is appropriately dried to form a polymer layer.

[0191] When applying the layer-forming solution, a known apparatus such as a spin coater, a blade coater, or a gravure coater can be used.

[0192] To dry the resulting coating film or improve the gas barrier properties of the gas barrier laminate, the coating film is preferably heated. Conventional drying methods such as hot air drying, hot roll drying, and infrared irradiation can be used for heating and drying. The heating temperature is typically 80 to 150°C, and the heating time is typically several tens of seconds to several tens of minutes.

[0193] When forming the gas barrier layer of the gas barrier laminate, for example, when the polysilazane compound described above is used, heating after coating causes a conversion reaction of the polysilazane to produce a coating film having excellent gas barrier properties.

[0194] On the other hand, when using a resin layer with low heat resistance, there is a risk of deformation of the resin layer due to heating during film formation. This deformation of the resin layer could adversely affect the gas barrier properties of the gas barrier layer of the gas barrier laminate. However, because the resin layer in embodiments of the present invention has excellent heat resistance, it does not deform even when heated during or after coating. Therefore, a reduction in the gas barrier properties of the gas barrier laminate due to deformation of the resin layer can be avoided.

[0195] The thickness of the polymer layer is usually 20 to 1000 nm, preferably 30 to 800 nm, and more preferably 40 to 400 nm.

[0196] Even if the thickness of the polymer layer is on the nanometer order, a gas barrier laminate having sufficient gas barrier performance can be obtained by subjecting it to a modification treatment as described later.

[0197] Examples of modification treatments include ion implantation and vacuum ultraviolet irradiation. Among these, ion implantation is preferred from the perspective of achieving high gas barrier properties. During ion implantation, the amount of ions implanted into the polymer layer can be appropriately determined based on the intended use of the resulting gas barrier laminate (e.g., required gas barrier properties, transparency, etc.).

[0198] Examples of the ions to be implanted include:

[0199] Ions of noble gases such as argon, helium, neon, krypton, and xenon; ions of fluorocarbons, hydrogen, nitrogen, oxygen, carbon dioxide, chlorine, fluorine, and sulfur;

[0200] Ions of alkane gases such as methane, ethane, propane, butane, pentane, and hexane; ions of olefin gases such as ethylene, propylene, butene, and pentene; ions of alkadiene gases such as pentadiene and butadiene; ions of alkyne gases such as acetylene and methylacetylene; ions of aromatic hydrocarbon gases such as benzene, toluene, xylene, indene, naphthalene, and phenanthrene; ions of cycloalkane gases such as cyclopropane and cyclohexane; ions of cycloalkene gases such as cyclopentene and cyclohexene;

[0201] Ions of conductive metals such as gold, silver, copper, platinum, nickel, palladium, chromium, titanium, molybdenum, niobium, tantalum, tungsten, and aluminum;

[0202] ions of silane (SiH4) or organosilicon compounds; and so on.

[0203] Examples of the organosilicon compound include:

[0204] Tetraalkoxysilanes such as tetramethoxysilane, tetraethoxysilane, tetra-n-propoxysilane, tetraisopropoxysilane, tetra-n-butoxysilane, and tetra-tert-butoxysilane;

[0205] Unsubstituted or substituted alkylalkoxysilanes such as dimethyldimethoxysilane, dimethyldiethoxysilane, diethyldimethoxysilane, methyltriethoxysilane, ethyltrimethoxysilane, and (3,3,3-trifluoropropyl)trimethoxysilane;

[0206] Aryl alkoxysilanes such as diphenyldimethoxysilane and phenyltriethoxysilane;

[0207] Disiloxanes such as hexamethyldisiloxane (HMDSO);

[0208] Aminosilanes such as bis(dimethylamino)dimethylsilane, bis(dimethylamino)methylvinylsilane, bis(ethylamino)dimethylsilane, diethylaminotrimethylsilane, dimethylaminodimethylsilane, tetrakisdimethylaminosilane, and tris(dimethylamino)silane;

[0209] Silazanes such as hexamethyldisilazane, hexamethylcyclotrisilazane, heptamethyldisilazane, nonamethyltrisilazane, octamethylcyclotetrasilazane, and tetramethyldisilazane;

[0210] Cyanatosilanes such as tetraisocyanatosilane;

[0211] Halosilanes such as triethoxyfluorosilane;

[0212] Alkenyl silanes such as diallyldimethylsilane and allyltrimethylsilane;

[0213] Unsubstituted or substituted alkylsilanes such as di-tert-butylsilane, 1,3-disilabutane, bis(trimethylsilyl)methane, tetramethylsilane, tris(trimethylsilyl)methane, tris(trimethylsilyl)silane, and benzyltrimethylsilane;

[0214] Silylalkynes such as bis(trimethylsilyl)acetylene, trimethylsilylacetylene, and 1-(trimethylsilyl)-1-propyne;

[0215] Silyl olefins such as 1,4-bis(trimethylsilyl)-1,3-butadiyne and cyclopentadienyltrimethylsilane;

[0216] Arylalkylsilanes such as phenyldimethylsilane and phenyltrimethylsilane;

[0217] Alkynylalkylsilanes such as propynyltrimethylsilane;

[0218] Alkenyl alkyl silanes such as vinyltrimethylsilane;

[0219] Disilanes such as hexamethyldisilane;

[0220] Siloxanes such as octamethylcyclotetrasiloxane, tetramethylcyclotetrasiloxane, and hexamethylcyclotetrasiloxane;

[0221] N,O-bis(trimethylsilyl)acetamide;

[0222] bis(trimethylsilyl)carbodiimide; and the like.

[0223] These ions can be used alone or in combination of two or more.

[0224] Among them, at least one ion selected from hydrogen, nitrogen, oxygen, argon, helium, neon, xenon, and krypton is preferred because implantation can be performed more easily and a gas barrier layer having particularly excellent gas barrier properties can be obtained.

[0225] The method of ion implantation is not particularly limited, and examples thereof include irradiation with ions accelerated by an electric field (ion beam), and ion implantation in plasma. Of these, the latter method of plasma ion implantation is preferred because it allows for easy production of a gas barrier film.

[0226] As the plasma ion implantation method, preferred are: (I) a method of implanting ions present in a plasma generated using an external electric field into a polymer layer; or (II) a method of implanting ions present in a plasma generated only by an electric field generated by a negative high voltage pulse applied to the above layer without using an external electric field.

[0227] In the above method (I), the pressure during ion implantation (pressure during plasma ion implantation) is preferably set to 0.01 to 1 Pa. When the pressure during plasma ion implantation is within this range, ions can be implanted simply and efficiently and uniformly, thereby efficiently forming the target gas barrier layer.

[0228] The above-mentioned method (II) does not require increasing the vacuum level, is simple to operate, and can significantly shorten the processing time. Furthermore, the entire layer can be treated uniformly, and when a negative high-voltage pulse is applied, ions in the plasma can be continuously injected into the polymer layer at high energy. Furthermore, no special means such as radio frequency (RF) or microwave power sources are required; high-quality ions can be uniformly injected into the polymer layer simply by applying a negative high-voltage pulse to the layer.

[0229] In either of the above methods (I) and (II), the pulse width when applying the negative high voltage pulse, i.e., when performing ion implantation, is preferably 1 to 15 μsec. When the pulse width is within this range, ions can be implanted more simply and efficiently and uniformly.

[0230] The applied voltage for plasma generation is preferably -1 to -50 kV, more preferably -1 to -30 kV, and particularly preferably -5 to -20 kV. When ion implantation is performed at an applied voltage greater than -1 kV, the ion implantation amount (dose) becomes insufficient, and the desired performance cannot be achieved. On the other hand, when ion implantation is performed at a voltage less than -50 kV, it can cause charging of the membrane during ion implantation and can lead to undesirable effects such as discoloration of the membrane, which is not preferred.

[0231] As the ion species to be implanted by plasma ion implantation, those exemplified above as the implanted ions can be cited.

[0232] When ions in plasma are implanted into the polymer layer, a plasma ion implantation apparatus is used.

[0233] Specific examples of plasma ion implantation devices include: (i) a device that superimposes high-frequency power on a feedthrough for applying a negative high-voltage pulse to a polymer layer (hereinafter also referred to as "the layer to be implanted") so that the layer to be implanted is uniformly surrounded by plasma, thereby inducing, injecting, colliding, and depositing ions in the plasma (Japanese Patent Publication No. 2001-26887); (ii) a device that sets an antenna in a chamber, applies high-frequency power to generate plasma, and after the plasma reaches the layer to be implanted, alternately applies positive and negative pulses to the layer to be implanted, thereby using positive pulses to induce the ions in the plasma to collide with each other and deposit. (iii) a plasma ion implantation apparatus that uses an external electric field such as a high-frequency power source such as microwaves to generate plasma and applies a high-voltage pulse to induce and inject ions in the plasma; (iv) a plasma ion implantation apparatus that does not use an external electric field and only uses the electric field generated by applying a high-voltage pulse to implant ions in the plasma, etc.

[0234] Among these apparatuses, the plasma ion implantation apparatus of (iii) or (iv) is preferably used because the treatment operation is simple, the treatment time can be significantly shortened, and it is suitable for continuous use.

[0235] As a method using the plasma ion implantation apparatus of (iii) and (iv) above, there is mentioned the method described in International Publication No. WO2010 / 021326.

[0236] In the plasma ion implantation apparatuses of (iii) and (iv) above, since the plasma generating means for generating plasma is also used as a high-voltage pulse power supply, other special means such as high-frequency power sources such as RF and microwaves are not required. Plasma can be generated and ions in the plasma can be continuously injected into the polymer layer only by applying a negative high-voltage pulse, thereby realizing mass production of a gas barrier laminate having a polymer layer having a portion on its surface modified by ion implantation, i.e., a gas barrier layer.

[0237] The thickness of the portion to be implanted with ions can be controlled by implantation conditions such as ion type, applied voltage, and treatment time, and can be determined according to the thickness of the polymer layer and the intended use of the gas barrier laminate, and is generally 5 to 1000 nm.

[0238] The implantation of ions can be confirmed by performing elemental analysis measurement near 10 nm from the surface of the polymer layer using X-ray photoelectron spectroscopy (XPS).

[0239] The gas barrier layer can be confirmed to have gas barrier properties based on the fact that the water vapor permeability of the gas barrier layer is low.

[0240] The water vapor transmission rate of the gas barrier layer in an atmosphere of 40°C and 90% relative humidity is usually 1.0 g / m 2 / day or less, preferably 0.8g / m 2 / day or less, more preferably 0.5g / m 2 / day or less, more preferably 0.1g / m 2 The water vapor transmission rate can be measured by a known method.

[0241] 1-7. Conductive layer

[0242] The conductive layer provided in the optical laminate according to the embodiment of the present invention is not particularly limited in material as long as it has conductivity, but is preferably a transparent conductive layer. Here, "transparent" means a light transmittance of 80% or more at a wavelength of 450 nm.

[0243] Conductive materials constituting the transparent conductive layer include metals, alloys, metal oxides, conductive compounds, and mixtures thereof. Specific examples include antimony-doped tin oxide (ATO); fluorine-doped tin oxide (FTO); semiconductive metal oxides such as tin oxide, germanium-doped zinc oxide (GZO), zinc oxide, indium oxide, indium tin oxide (ITO), and indium zinc oxide (IZO); metals such as gold, silver, chromium, and nickel; mixtures of these metals with conductive metal oxides; inorganic conductive materials such as copper iodide and copper sulfide; and organic conductive materials such as polyaniline, polythiophene, and polypyrrole. Metals such as silver can also be aggregated into a transparent conductive layer using particulate materials such as nanofillers, nanorods, and nanofibers.

[0244] The method for forming the transparent conductive layer is not particularly limited. Examples thereof include vapor deposition, sputtering, ion plating, thermal CVD, and plasma CVD. Alternatively, the transparent conductive layer can be formed from a coating film by, for example, applying a coating material containing a particulate metal to the transparent conductive film laminate.

[0245] The thickness of the transparent conductive layer may be appropriately selected depending on the intended use, etc. It is usually 10 nm to 50 μm, and preferably 20 nm to 20 μm.

[0246] 1-8. Peel sheet (α)

[0247] The release sheet (α) plays a role in protecting the resin layer during storage, transportation, etc. of the optical laminate, and is a material that is peeled off in a predetermined step.

[0248] The release sheet (α) is preferably a sheet or film. The sheet or film is not limited to a long strip shape, and includes a rectangular flat plate shape.

[0249] Examples of the release sheet (α) include: paper substrates such as glassine paper, coated paper, and high-quality paper; laminated paper obtained by laminating a thermoplastic resin such as polyethylene or polypropylene on these paper substrates; materials obtained by caulking the above-mentioned paper substrates with cellulose, starch, polyvinyl alcohol, acrylic-styrene resin, etc.; or plastic films such as polyester films such as polyethylene terephthalate, polybutylene terephthalate, and polyethylene naphthalate, and polyolefin films such as polyethylene and polypropylene; glass, etc.

[0250] Furthermore, the release sheet (α) may be a material having a release agent layer provided on a paper substrate or a plastic film from the perspective of ease of handling. However, when a curable composition is applied to the release sheet (α) to form a resin layer, it is preferable that no release agent layer be present to avoid the curable composition not being able to spread on the release sheet (α), resulting in an uneven coating or uncoated areas. In other words, it is preferable that the release sheet (α) not have a release agent layer, but rather the resin layer be formed directly on the release sheet (α).

[0251] When a release agent layer is provided, the release agent layer can be formed using a conventionally known release agent such as a silicone release agent, a fluorine release agent, an alkyd release agent, or an olefin release agent.

[0252] The thickness of the release agent layer is not particularly limited, but is usually 0.02 to 2.0 μm, more preferably 0.05 to 1.5 μm.

[0253] Furthermore, the resin layer is generally flexible. If the release sheet (α) has an adhesive layer, there is a risk that the adhesive layer and the resin layer will adhere to each other. Therefore, it is preferred that the release sheet (α) also does not have an adhesive layer.

[0254] The thickness of the release sheet (α) is preferably 25 to 150 μm, more preferably 40 to 125 μm, from the viewpoints of maintaining heat resistance, avoiding an increase in release force due to an increase in the release area, and reducing strain generated in the optical laminate during winding.

[0255] The surface roughness Ra (arithmetic mean roughness) of the release sheet (α) is preferably 10.0 nm or less, more preferably 8.0 nm or less. The surface roughness Rt (maximum cross-sectional height) is preferably 100 nm or less, more preferably 50 nm or less.

[0256] When the surface roughness Ra and Rt are 10.0 nm or less and 100 nm or less, respectively, the surface roughness of the layer in contact with the process film can be prevented from becoming excessively large. Therefore, when the optical laminate includes the above-mentioned functional layers, gas barrier layers, conductive layers, etc., these layers can easily exhibit their intended functions.

[0257] In addition, surface roughness Ra and Rt are values ​​obtained by the optical interferometry method with a measurement area of ​​100 μm×100 μm.

[0258] 1-9. Protective film (β)

[0259] The protective film (β) has a function of protecting functional layers such as the gas barrier layer and the transparent conductive layer during storage and transportation of the optical laminate, and is peeled off in a predetermined step.

[0260] The protective film (β) is preferably a sheet-like or film-like film. The sheet-like or film-like form is not limited to a long strip shape, and also includes a rectangular flat plate shape.

[0261] The protective film (β) is usually pasted on the surface of the resin layer or other layers after the resin layer or other layers on the resin layer contained in the optical film are formed. Therefore, from the perspective of preventing the protective film (β) from falling off unexpectedly from the resin layer or other layers, it is preferably a structure in which an adhesive layer is provided on the substrate. In this case, an adhesive layer is provided on the surface of the optical film side of the protective film (β). By providing the protective film (β) with an adhesive layer, the protective film (β) can be attached in a manner that allows it to be peeled off relative to the resin layer or other layers. As the substrate of the protective film (β), a material of the same material / thickness as the peeling sheet (α) can be used.

[0262] The adhesive strength of the adhesive layer is adjusted by selecting its material, thickness, etc.: the adhesive strength A2 when the protective film (β) is peeled off from the resin layer of the optical film or other layers on the resin layer at a low peeling speed of 0.3 m / min, and the peeling strength A1 when the peeling sheet (α) is peeled off from the resin layer at a low peeling speed of 0.3 m / min satisfy the relationship A1>A2.

[0263] Examples of adhesives constituting the adhesive layer include acrylic adhesives, urethane adhesives, silicone adhesives, rubber adhesives, adhesives comprising polyolefin polymers, and adhesives comprising polyolefin copolymers. Among these, it is more preferred that the adhesive layer comprise at least one of a polyolefin polymer and a polyolefin copolymer, from the perspective of easily achieving an adhesive strength A2 that readily achieves the relationship A1>A2. Examples of polyolefin polymers include polyethylene and polypropylene, and examples of polyolefin copolymers include ethylene-vinyl acetate copolymers and ethylene-(meth)acrylic acid copolymers.

[0264] Examples of commercially available protective films made of a polyolefin-based adhesive that can be used as the protective film (β) include SANYTECT PAC-3-50THK and SANYTECT PAC-2-70 manufactured by Sun A. Kaken Co., Ltd.

[0265] 1-10. Other structural examples of optical laminates

[0266] The optical laminate according to the embodiment of the present invention is not limited to Figure 1The laminate shown may also be a laminate comprising a plurality of stacked layers, each comprising a resin layer and the aforementioned other layers. Furthermore, one, two, or more additional layers may be included between the resin layer and the aforementioned other layers, without impairing the objectives of the present invention. When multiple stacked layers of the aforementioned resin layer and gas barrier layer are included, one, two, or more additional layers may be included between at least one of the adjacent stacks.

[0267] Examples of the additional layer include a conductor layer, a shock absorbing layer, an adhesive layer, a bonding layer, and a process sheet. The position of the additional layer is not particularly limited.

[0268] Materials constituting the conductive layer include metals, alloys, metal oxides, conductive compounds, and mixtures thereof. Specific examples include antimony-doped tin oxide (ATO); fluorine-doped tin oxide (FTO); semiconductive metal oxides such as tin oxide, germanium-doped zinc oxide (GZO), zinc oxide, indium oxide, indium tin oxide (ITO), and indium zinc oxide (IZO); metals such as gold, silver, chromium, and nickel; mixtures of these metals with conductive metal oxides; inorganic conductive materials such as copper iodide and copper sulfide; and organic conductive materials such as polyaniline, polythiophene, and polypyrrole.

[0269] The method for forming the conductive layer is not particularly limited, and examples thereof include vapor deposition, sputtering, ion plating, thermal CVD, and plasma CVD.

[0270] The thickness of the conductor layer may be appropriately selected depending on the intended use, etc. It is usually 10 nm to 50 μm, and preferably 20 nm to 20 μm.

[0271] The impact-absorbing layer is a layer used to protect the functional layer, gas barrier layer, conductive layer, and other layers described above from impact. The material forming the impact-absorbing layer is not particularly limited, and examples thereof include acrylic resins, urethane resins, silicone resins, olefin resins, and rubber materials.

[0272] The method for forming the impact absorbing layer is not particularly limited. For example, a method of forming the impact absorbing layer by applying a solution for forming the impact absorbing layer containing the above-mentioned material for forming the impact absorbing layer and other components such as a solvent as needed onto the layer to be laminated, drying the resulting coating film, and heating the film as needed can be used to form the impact absorbing layer.

[0273] Alternatively, the impact absorbing layer may be separately formed on a release substrate, and the resulting film may be transferred onto a layer to be laminated.

[0274] The thickness of the impact absorbing layer is usually 1 to 100 μm, preferably 5 to 50 μm.

[0275] The adhesive layer is a layer used when the optical laminate is attached to an adherend. The material forming the adhesive layer is not particularly limited, and known adhesives or pressure-sensitive adhesives such as acrylic, silicone, and rubber, and heat-sealing materials may also be used.

[0276] The bonding layer is a layer used in the case of manufacturing an optical laminated body by combining a resin layer and the above-mentioned other layers as a group and combining multiple groups. The bonding layer is used to bond the resin layer contained in each adjacent group with the above-mentioned other layers to maintain the laminated structure. The bonding layer can be a single layer or a multilayer. Examples of the bonding layer include a layer composed of a single layer structure formed using an adhesive and a layer formed by forming layers formed using an adhesive on both sides of a support layer.

[0277] The material used to form the bonding layer is not particularly limited as long as it can bond the resin layer and the group of the above-mentioned other layers to each other and maintain the stacked structure. Known adhesives can be used, but from the perspective of being able to bond the resin layer and the group of the above-mentioned other layers to each other at room temperature, adhesives are preferred.

[0278] Examples of adhesives used in the bonding layer include acrylic adhesives, urethane adhesives, silicone adhesives, and rubber adhesives. Among these, acrylic adhesives and urethane adhesives are preferred from the perspectives of adhesive strength, transparency, and ease of handling. Furthermore, adhesives capable of forming a cross-linked structure as described below are preferred.

[0279] The adhesive may be any type of adhesive such as a solvent-based adhesive, an emulsion-based adhesive, or a hot-melt-based adhesive.

[0280] 1-11. Rolled optical laminate

[0281] Figure 2 It is a schematic cross-sectional view showing an example of a rolled gas barrier laminate as a rolled optical laminate.

[0282] Figure 2 The rolled gas barrier layered product 10A shown includes a rolled portion 10A1 wound around a cylindrical or rod-shaped core material 11. The front end of the rolled portion 10A1 is pulled out to form a pulled-out portion 10A2.

[0283] exist Figure 2 In the rolled gas barrier laminate 10A shown, a rolled portion 10A1 is formed so that the protective film 4 is located outside the release sheet 1. This makes it possible to reduce stress on the protective film 4 in the rolled portion 10A1.

[0284] In the optical laminate of the present invention, the protective film (β) can be properly peeled off at any stage, whether it is low-speed peeling at the peeling starting point or high-speed peeling thereafter. Therefore, when the protective film (β) is continuously peeled off from a roll of optical laminate, as long as the protective film (β) can be properly peeled off at a low speed at the peeling starting point, the protective film (β) can also be properly peeled off at a high-speed peeling in the subsequent roll-to-roll process.

[0285] Figure 3 This is a schematic cross-sectional view showing another example of the rolled gas barrier laminate as a rolled optical laminate.

[0286] Figure 3 The rolled gas barrier laminate 10B shown has a rolled portion 10B1 wound around a core material 11. Furthermore, the front end portion of the rolled portion 10B1 is pulled out to form a pulled-out portion 10B2.

[0287] exist Figure 3 In the rolled gas barrier laminate 10B shown, the rolled portion 10B1 is formed so that the protective film 4 is located inside the release sheet 1. This makes it easier to prevent the protective film 4 from peeling off due to contact with foreign objects during storage and transportation of the gas barrier laminate 10B.

[0288] 1-12. Method of using optical laminate

[0289] When the optical laminate is used, the protective film (β) and the release sheet (α) are peeled off from the optical laminate, and the laminate is then used in a state of being attached to a target adherend such as a display or an electronic device.

[0290] Figure 5 It shows that Figure 1 A diagram showing an example of a method of using the gas barrier laminate having the structure shown.

[0291] In this example, first, Figure 5 (a)~ Figure 5 As shown in (b), the protective film 4 is peeled off from the gas barrier layer 3. When the protective film 4 is peeled off, it is required that the release sheet 1 remain in close contact with the resin layer 2 without warping or peeling off. By maintaining the release sheet 1 in close contact with the resin layer 2 after the protective film 4 is peeled off, the gas barrier layer can continue to be protected in subsequent steps.

[0292] Then, if Figure 5 As shown in (c), an adhesive layer 5 is formed on the surface of the exposed gas barrier layer 3, and Figure 5As shown in (d), the gas barrier layer 3 of the gas barrier laminate 10, after the protective film 4 has been removed, is bonded and fixed to the surface of the adherend 20 using the adhesive layer 5. The adhesive layer 5 can be formed using any material that can be used for the adhesive layer described above. It should be noted that if the adherend already has an adhesive layer, the step of forming the adhesive layer 5 can be omitted.

[0293] Afterwards, through Figure 5 As shown in (e), the release sheet 1 is peeled off from the resin layer 2 , so that the gas barrier film 10 a is attached to the adherend 20 .

[0294] 1-13. Method for producing optical laminate

[0295] The optical laminate according to the embodiment of the present invention is produced using a release sheet (α). By using a release sheet (α), the optical laminate can be produced efficiently and easily. A method including the following steps 1 to 4 is particularly preferred.

[0296] Step 1: Forming a curable resin layer on a release sheet (α) using a curable resin composition containing a polymer component (A) and a curable monomer (B)

[0297] Step 2: Step of curing the curable resin layer obtained in Step 1 to form a resin layer composed of a cured resin layer

[0298] Step 3: Step of forming other layers such as a functional layer, a gas barrier layer, and a conductive layer on the resin layer obtained in Step 2

[0299] Step 4: A step of laminating a protective film (β) on other layers such as the functional layer, gas barrier layer, and conductive layer obtained in step 3

[0300] Figure 4 An example of a process for producing a gas barrier laminate, which is one of the optical laminates according to the embodiment of the present invention, is shown. Figure 4 (a)~ Figure 4 (b) corresponds to the above step 1, Figure 4 (c)~ Figure 4 (d) corresponds to the above step 2, Figure 4 (e) corresponds to the above step 3, Figure 4 (f) corresponds to the above step 4.

[0301] (Process 1)

[0302] First, on the peeling sheet (α) (equivalent to Figure 4 In the symbol 1) of (a), a curable resin composition containing a polymer component (A) and a curable monomer (B) is used to form a curable resin layer (equivalent to Figure 4(b) Symbol 2a).

[0303] The method for applying the curable resin composition to the release sheet (α) is not particularly limited, and known coating methods such as spin coating, spray coating, bar coating, knife coating, roll coating, doctor blade coating, die coating, and gravure coating can be used.

[0304] The method for drying the resulting coating film is not particularly limited, and conventional drying methods such as hot air drying, hot roll drying, and infrared irradiation can be used. Even if the curable resin composition for forming the resin layer contains a polymer component (A) having a very high Tg, the inclusion of the curable monomer (B) allows efficient removal of the solvent when drying a coating film obtained by a solution casting method.

[0305] The drying temperature of the coating film is usually 30 to 150° C., preferably 50 to 120° C. The drying time is usually 1 to 10 minutes, more preferably 2 to 7 minutes.

[0306] The thickness of the dried coating film (curable resin layer) is not particularly limited. Since the thickness is substantially the same as that after curing, it may be the same as the thickness of the resin layer described above.

[0307] (Process 2)

[0308] Next, the curable resin layer obtained in step 1 is cured to form a cured resin layer. This cured resin layer becomes a resin layer ( Figure 4 (c) Symbol 2).

[0309] The method for curing the curable resin layer is not particularly limited, and known methods can be employed. For example, when the curable resin layer is formed using a curable resin composition containing a thermal polymerization initiator, the curable resin layer can be cured by heating the curable resin layer. The heating temperature is generally 30 to 150°C, preferably 50 to 100°C.

[0310] In addition, when the curable resin layer is formed using a curable resin composition containing a photopolymerization initiator, the curable resin layer can be cured by irradiating the curable resin layer with electromagnetic waves as active energy rays. The electromagnetic waves can be irradiated using a high-pressure mercury lamp, an electrodeless lamp, a xenon lamp, or the like.

[0311] The wavelength of the electromagnetic wave is preferably in the ultraviolet range of 200 to 400 nm, more preferably 350 to 400 nm. The irradiation intensity is usually 50 to 1000 mW / cm 2 , light intensity 50~5000mJ / cm 2 , preferably 200 to 5000 mJ / cm 2The irradiation time is usually 0.1 to 1000 seconds, preferably 1 to 500 seconds, and more preferably 10 to 100 seconds. Considering the heat load of the irradiation process, multiple irradiations may be performed to meet the above-mentioned light intensity.

[0312] In this case, in order to prevent degradation of the polymer component (A) and coloration of the resin layer due to electromagnetic waves, the curable resin composition may be irradiated with electromagnetic waves through a filter that absorbs light of wavelengths not necessary for the curing reaction. According to this method, since light of wavelengths not necessary for the curing reaction and that may cause degradation of the polymer component (A) is absorbed by the filter, degradation of the polymer component (A) can be suppressed, and a colorless and transparent resin layer can be easily obtained.

[0313] A resin film such as polyethylene terephthalate film can be used as a filter. When using a resin film, it is preferable to include a step between Steps 1 and 2 to laminate the resin film such as polyethylene terephthalate film on the curable resin layer. It should be noted that the resin film is usually peeled off after Step 2.

[0314] Alternatively, the curable resin layer may be cured by irradiating the curable resin layer with an electron beam as an active energy ray. When irradiating with an electron beam, an electron beam accelerator or the like may be used. The irradiation dose is generally in the range of 10 to 1000 krad. The irradiation time is generally 0.1 to 1000 seconds, preferably 1 to 500 seconds, and more preferably 10 to 100 seconds.

[0315] The curing of the curable resin layer can be performed in an inert gas atmosphere such as nitrogen, as needed. By performing curing in an inert gas atmosphere, it is easy to avoid the interference of oxygen, moisture, etc. on the curing.

[0316] As described above, the resin film formed in the order of coating, drying, and curing can be formed thinly, and therefore has rich flexibility and can be formed into a film with optical isotropy. In addition, since it is a curable resin, it can be formed into a film with excellent heat resistance and solvent resistance.

[0317] (Process 3)

[0318] Thereafter, a layer of the composition for forming a gas barrier layer, that is, a gas barrier layer before curing ( Figure 4 (d) symbol 3a), the composition layer is cured to form a gas barrier layer ( Figure 4 (e) Symbol 3) When the gas barrier layer is formed by an inorganic film by vapor deposition or the like, Figure 4 The state of (c) is directly transferred to Figure 4 (e) Status.

[0319] As a method for forming the gas barrier layer, the method described above can be appropriately adopted.

[0320] For example, when the gas barrier layer is a layer obtained by subjecting a layer containing a silicon-containing polymer compound to a modification treatment, the gas barrier layer can be formed by forming the layer containing the silicon-containing polymer compound on the resin layer and subjecting the layer containing the silicon-containing polymer compound to a modification treatment.

[0321] The gas barrier layer included in a gas barrier laminate can be formed using various methods, such as extrusion molding and coating. However, depending on the method used to form the gas barrier layer, the gas barrier performance of the gas barrier laminate may be reduced. In particular, when the gas barrier layer is formed using a method involving heating, such as coating and drying, there is a risk that the resin layer will be physically or chemically affected, resulting in a reduction in gas barrier properties.

[0322] As a method for forming a layer containing a silicon-containing polymer compound and a method for performing a modification treatment, the methods described above can be employed.

[0323] In addition, as a method for performing the modification treatment, it is preferred to produce a gas barrier laminate by performing a modification treatment on the layer containing the silicon-containing polymer compound while conveying a long film on the resin layer obtained in step 2 in a certain direction.

[0324] According to this production method, for example, a long-length gas barrier laminate can be continuously produced.

[0325] (Process 4)

[0326] A gas barrier laminate can be obtained by attaching a protective film (β) to the gas barrier layer obtained in step 3. This step can be performed, for example, by placing the adhesive layer-formed surface of the protective film (β) toward the gas barrier layer and sequentially pressing the protective film (β) so as not to introduce air bubbles.

[0327] As described above, the production method including the above steps 1 to 4 is a method of forming a curable resin layer using a release sheet (α), and can produce the gas barrier laminate according to the embodiment of the present invention continuously and easily with good efficiency.

[0328] Example

[0329] Next, specific examples of the present invention will be described, but the present invention is not limited to these examples. The peel forces A1 and B1, and the adhesive forces A2 and B2 of the gas barrier laminates and optical laminates produced in the Examples and Comparative Examples described below were measured, and the appearance of the protective film (β) was evaluated after peeling. Furthermore, the water vapor transmission rate of the gas barrier film used in each gas barrier laminate was measured and calculated according to the following procedures.

[0330] [Determination of peel strength and adhesive strength]

[0331] The protective films or release sheets of the gas barrier laminate and the optical laminate (all 50 mm wide) were peeled off at a peel angle of 180° and a peel rate of 0.3 m / min or 20 m / min, and the peel force and adhesive strength (mN / 50 mm) were measured. The test environment was 23°C and 50% relative humidity. A low-speed peel tester (TENSILON Universal Testing Machine RTG-1225, manufactured by A&D Co., Ltd.) was used for the peel test at a peel rate of 0.3 m / min, while a high-speed peel tensile tester (TESTER SANGYO Co., Ltd., TE-701 High-Speed ​​Peel Tester) was used for the peel test at a peel rate of 20 m / min.

[0332] In the measurement of the peeling force A1, for the gas barrier laminate, as shown in FIG. Figure 6 As shown in (a), the gas barrier layer 3 was adhered to the glass plate 30 using a double-sided adhesive film 5 before the protective film (β) was attached to the gas barrier layer 3. The sample prepared in this manner served as the measurement sample. For optical laminates, the resin layer before the protective film (β) was attached was adhered to the glass plate using a double-sided adhesive film. The sample prepared in this manner served as the measurement sample. The release sheet (α) was then peeled off from these measurement samples, and the peel force A1 was measured.

[0333] In the measurement of the adhesive force A2, the gas barrier laminate was replaced with the gas barrier film of the examples and comparative examples. Figure 6As shown in (b), a gas barrier layer 3 is formed on a polyethylene terephthalate (PET) film substrate 40 having a thickness of 50 μm in the same order as in the embodiment and the comparative example, and a protective film (β) is pasted on the gas barrier layer and kept in the above-mentioned test environment for 24 hours. Then, the surface of the PET film substrate 40 opposite to the gas barrier layer 3 is fixed to the glass plate 30 using a double-sided adhesive film 5, and the sample prepared in this way is used as a measurement sample. For an optical laminate, the resin layer before pasting the protective film (β) is adhered to the glass plate using a double-sided adhesive film, and the sample prepared in this way is used as a measurement sample. Then, the peeling sheet (α) is peeled off from these measurement samples, and the adhesive force A2 is measured. The calculation of the measured value is based on JIS Z0237:2000, and the average value of the two measurements is used as each peeling force and adhesive force.

[0334] It should be noted that, regarding the final gas barrier laminates and optical laminates obtained in the examples and comparative examples, even if the protective film (β) is removed when measuring the peeling force A1 and the release sheet (α) is removed when measuring the adhesive force A2, the surface opposite to the peeling release sheet (α) or protective film (β) is fixed to the glass plate 30 for measurement, the same values ​​as those of the peeling force A1 and adhesive force A2 measured in the above order will be obtained.

[0335] [Appearance evaluation]

[0336] The exposed surface of the release sheet 1 of the gas barrier laminate produced in the Examples and Comparative Examples was fixed to a glass plate 30 using a double-sided adhesive film 5 to prepare evaluation samples. The appearance of the remaining laminate, after peeling the protective film 4 at a peeling rate of 0.3 m / min or 20 m / min, was visually observed. A rating of "G" was given if the appearance was normal and the resin layer did not warp or peel. A rating of "F" was given if at least one of warping and peeling of the resin layer occurred. The appearance of the optical laminate produced in the Examples was evaluated in the same manner as described above.

[0337] <Example 1>

[0338] (1) Preparation of resin layer

[0339] As a polymer component, 100 parts by mass of polyimide resin (PI) pellets (KPI-MX300F, Tg = 354°C, weight-average molecular weight 280,000, manufactured by Kawamura Industrial Co., Ltd.) were dissolved in a solvent containing methyl ethyl ketone to prepare a 15% PI solution. Subsequently, 122 parts by mass of tricyclodecane dimethanol diacrylate (A-DCP, manufactured by Shin-Nakamura Chemical Co., Ltd.) as a curable compound and 5 parts by mass of bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide (Omnirad TPO, manufactured by BASF) as a polymerization initiator were added and mixed to this solution to prepare Curable Composition 1. It should be noted that the curable compounds and polymerization initiators used in this example and other experimental examples did not contain a solvent and were all raw materials with a 100% solids content.

[0340] Next, a polyethylene terephthalate (PET) film (manufactured by Toyobo Co., Ltd., COSMOSHINE PET100A4100, thickness 100 μm) was prepared as a release sheet (α), and a curable resin composition was applied to the side opposite to the easily adhesive layer by manual coating. The resulting coating was heated at 100° C. for 3 minutes to dry the coating.

[0341] Then, a PET film (manufactured by Toyobo Co., Ltd., COSMOSHINE PET50A4100, thickness 50 μm) having an easy-bonding layer on one side was laminated on the dried coating film, with the sides opposite to the easy-bonding side facing each other. The film was irradiated with a high-pressure mercury lamp (manufactured by Eye Graphics, product name: H04-L41) using a conveyor-type ultraviolet irradiation device (Eye Graphics, product name: ECS-401GX) at a lamp height of 100 mm, an output of 3 kW, and an illuminance of 150 mW / cm2 at a wavelength of 365 nm. 2 , light intensity 400mJ / cm 2 The curing reaction was carried out under the conditions of 1% tantalum sulfate (manufactured by ORC MANUFACTURING CO., LTD., measured with an ultraviolet spectrophotometer UV-351) to form a resin layer having a thickness of 5 μm.

[0342] (2) Lamination of gas barrier layers

[0343] Next, the PET film laminated on the coating film was peeled off to expose the resin layer. A polysilazane compound (a coating agent containing perhydropolysilazane (PHPS) as a main component (AQUAMICA NL-110-20 manufactured by Merck Performance Materials Co., Ltd., solvent: xylene)) was applied to the resin layer by spin coating, and then heated and dried at 100°C for 2 minutes to form a polymer compound layer (polysilazane layer) having a thickness of 200 nm containing perhydropolysilazane.

[0344] Next, using a plasma ion implantation system (RF power source: "RF" 56000, manufactured by JEOL Ltd.; high voltage pulse power source: PV-3-HSHV-0835, manufactured by Kurita Seisakusho Co., Ltd.), ions from argon gas were implanted into the surface of the polymer compound layer (polysilazane layer) under the following conditions: a gas flow rate of 100 sccm, a duty cycle of 0.5%, an applied DC voltage of -6 kV, a frequency of 1000 Hz, an applied RF power of 1000 W, a chamber pressure of 0.2 Pa, a DC pulse width of 5 μsec, and a treatment time of 200 seconds. This formed a gas barrier layer. By laminating the gas barrier layer on the resin layer in this manner, a gas barrier film was formed on the release sheet (α). The same process was repeated to obtain a gas barrier film with a release sheet having two gas barrier layers.

[0345] (3) Lamination of protective film

[0346] A polyolefin protective film (SANYTECT PAC-3-50THK, manufactured by Sun A. Kaken Co., Ltd. (low-density polyethylene substrate, olefin-based adhesive, thickness 50 μm)) was attached as a protective film (β-1) to the gas barrier layer side of the obtained gas barrier film to obtain a gas barrier laminate.

[0347] <Example 2>

[0348] In Example 1, a gas barrier laminate was obtained in the same manner as in Example 1, except that an ethylene-vinyl acetate copolymer (EVA)-based protective film (manufactured by Sun A. Kaken Co., Ltd., SANYTECT PAC-2-70 (low-density polyethylene base material, EVA-based adhesive, thickness 70 μm)) was used as the protective film (β-2) instead of the protective film (β-1).

[0349] <Comparative Example 1>

[0350] An adhesive composition (1) was prepared by mixing 100 parts by mass of an acrylic resin (Cyvinol LT-57, manufactured by Saiden Chemical Industry Co., Ltd.) and 4 parts by mass of an isocyanate crosslinking agent (Kokazai K-315, manufactured by Saiden Chemical Industry Co., Ltd.). A 5 μm thick adhesive layer was formed on a polyester film (PET38-600E, manufactured by Nissin Chemical Industry Co., Ltd.) using the adhesive composition (1) to prepare a protective film (β-3). A gas barrier laminate was then prepared by the same procedure as in Example 1, except that the protective film (β-3) was used instead of the protective film (β-1).

[0351] <Comparative Example 2>

[0352] 100 parts by mass of an acrylic resin (Cyvinol LT-55, manufactured by Saiden Chemical Industry Co., Ltd.), 1.6 parts by mass of an isocyanate crosslinking agent (Kokazai K-200, manufactured by Saiden Chemical Industry Co., Ltd.), and 2 parts by mass of an isocyanate crosslinking agent (Kokazai M-2, manufactured by Saiden Chemical Industry Co., Ltd.) were mixed to obtain an adhesive composition (2). A 5 μm thick adhesive layer was formed on a polyester film (PET38-T100G, manufactured by Nissin Chemical Industry Co., Ltd.) using the adhesive composition (2) to produce a protective film (β-4). A gas barrier laminate was then produced in the same manner as in Example 1, except that the protective film (β-4) was used instead of the protective film (β-1).

[0353] <Example 3>

[0354] An optical laminate was obtained by the same procedure as in Example 1, except that the gas barrier layer was not laminated and the protective film was directly attached to the resin layer.

[0355] <Example 4>

[0356] An optical laminate was obtained by the same procedure as in Example 2, except that the gas barrier layer was not laminated but the protective film was directly attached to the resin layer.

[0357] Table 1 shows the measurement results of the gas barrier laminates and optical laminates of Examples and Comparative Examples.

[0358] [Table 1]

[0359]

[0360] *1: PAC-3-50THK

[0361] *2: PAC-2-70

[0362] *3: PET base material + acrylic resin adhesive layer

[0363] *4: PET base material + acrylic resin adhesive layer

[0364] The results in Table 1 indicate that the gas barrier laminates of Examples 1 and 2 and the optical laminates of Examples 3 and 4 satisfy the relationship A1>A2 for the peeling force A1 when the release sheet (α) is peeled from the resin layer at a low peeling speed, and the adhesive force A2 when the protective film (β) is peeled from the gas barrier layer at a low peeling speed. Consequently, the laminates exhibit a good appearance even after the protective film (β) is peeled off. It should be noted that, although the peeling force B1 when the release sheet (α) is peeled from the resin layer at a low peeling speed, and the adhesive force B2 when the protective film (β) is peeled from the gas barrier layer at a low peeling speed, satisfy the relationship B2>B1 for the gas barrier laminates of Examples 1 and 2 and the optical laminates of Examples 3 and 4, satisfying the relationship A1>A2 facilitates the formation of a peeling starting point. Consequently, it is understood that the protective film (β) can be peeled off even under high-speed peeling conditions.

[0365] In contrast, it can be understood that in the gas barrier laminates of Comparative Examples 1 and 2, since the relationship between the release sheet (α) and the protective film (β) is A1<A2, it is not easy to form a peeling starting point under low-speed peeling conditions. As a result, when the protective film (β) is peeled off, the resin layer formed on the release sheet (α) will warp and peel off.

[0366] Industrial Applicability

[0367] The optical laminate of the present invention does not cause warping or peeling at the interface between the resin layer and the release sheet (α), and a peeling starting point can be appropriately formed between the protective film (β) and the resin layer or other layers. Therefore, peeling can be performed well under a wide range of peeling conditions, from low to high peeling speeds. Therefore, an optical laminate that can adapt to various manufacturing conditions can be formed for component parts of various electronic devices, such as organic EL elements and thermoelectric converters.

Claims

1. An optical laminate comprising a release sheet (α), an optical film, and a protective film (β), wherein the optical film comprises a resin layer on the outermost surface thereof. The release sheet (α) is directly laminated on the resin layer, The protective film (β) is laminated on the resin layer directly or via another layer from the outermost surface of the other side of the optical film. The resin layer is a cured product of a curable composition containing a curable compound. The protective film (β) has an adhesive layer, and is attached to the resin layer or the other layer in a releasable manner via the adhesive layer. The adhesive layer comprises at least one of a polyolefin polymer and a polyolefin copolymer, The peeling force A1 when the peeling sheet (α) is peeled off from the resin layer at a low peeling speed of 0.3 m / min, and the adhesive force A2 when the protective film (β) is peeled off from the resin layer or the other layer at a low peeling speed of 0.3 m / min satisfy the relationship A1>A2, The adhesive force B2 when the protective film (β) is peeled off from the above-mentioned resin layer or the above-mentioned other layer at a high-speed peeling condition of 20 m / min, and the peeling force B1 when the peeling sheet (α) is peeled off from the resin layer at a high-speed peeling condition of 20 m / min satisfy the relationship of 6.0×B1≥B2≥B1.

2. The optical laminate according to claim 1, wherein The peel force A1 is 500 mN / 50 mm or less.

3. The optical laminate according to claim 1 or 2, wherein The resin layer is a cured product of a curable resin composition containing a polymer component (A) and a curable monomer (B).

4. The optical laminate according to claim 3, wherein The glass transition temperature (Tg) of the polymer component (A) is 250° C. or higher.

5. The optical laminate according to claim 1 or 2, wherein The optical film includes a functional layer as the other layer, which is located on the outermost surface opposite to the outermost surface where the resin layer is located. The functional layer is a layer obtained by subjecting an inorganic film or a layer containing a polymer compound to a modification treatment, and the protective film (β) is directly laminated on the functional layer.

6. The optical laminate according to claim 1 or 2, wherein The optical film includes a gas barrier layer as the other layer, the gas barrier layer is located on the outermost surface opposite to the outermost surface where the resin layer is located, and the protective film (β) is directly laminated on the gas barrier layer.

7. The optical laminate according to claim 1 or 2, wherein The optical film includes a conductive layer as the other layer, the conductive layer is located on the outermost surface opposite to the outermost surface where the resin layer is located, and the protective film (β) is directly laminated on the conductive layer.

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