Optical laminate and reflection-preventing article, panel, and image display device using optical laminate

Abstract

Provided is an optical laminate that can impart favorable reflection prevention properties, even when applied to a member that is not flat. An optical laminate according to the present invention has a hard coat layer and a low refractive index layer in the given order on a resin substrate and satisfies conditions 1 and 2. Condition 1: When a 20 mm short side×100 mm long side first sample is cut from the optical laminate, the first sample is installed in a tension tester that has an inter-chuck distance of 50 mm, and the first sample is stretched in the long side direction at 130°C at a stretching speed of 50 mm / min, the elongation of the first sample at the upper yield point is at least 6.5%. Condition 2: When the average thickness of the low refractive index layer before the optical laminate is stretched is t1, and the average thickness of the low refractive index layer after stretching as measured under prescribed conditions is t2, the ratio of the thickness t2 of the low refractive index layer after stretching to the thickness t1 of the low refractive index layer before stretching as calculated from the following expression is 80%–99%.

Description

Optical laminate, and anti-reflection article, panel, and image display device using said optical laminate

[0001] The present disclosure relates to an optical laminate, and an anti-reflective article, a panel, and an image display device using the optical laminate.

[0002] An anti-reflection film may be provided on the surface of an image display device such as a liquid crystal display device, an organic EL display device, a micro LED display device, etc., in order to improve visibility. An anti-reflection film may also be provided on the surface of an article such as a showcase.

[0003] As an antireflection film, an optical laminate having an antireflection layer such as a low refractive index layer on a substrate has been proposed (Patent Document 1, etc.).

[0004] Japanese Patent Application Laid-Open No. 2022-150906

[0005] Most image display devices to date have had a flat shape. Therefore, an optical laminate having an antireflection layer would not pose a problem if it could provide good antireflection properties when applied to a flat shape. However, in recent years, display devices with non-flat shapes, such as display devices with curved surfaces and display devices with three-dimensional shapes, have been developed. When a conventional optical laminate having an antireflection layer such as that disclosed in Patent Document 1 is applied to such non-flat display devices, non-flat showcases, and other non-flat components, there have been frequent cases in which the reflectance becomes higher than the theoretical value.

[0006] An object of the present disclosure is to provide an optical laminate that can maintain good antireflection properties even when applied to a member with a non-flat shape. Another object of the present disclosure is to provide an antireflection article, a panel, and an image display device that use the optical laminate.

[0007] The present disclosure provides the following (1) to (4). (1) An optical laminate having a hard coat layer and a low refractive index layer on a resin substrate in this order, the optical laminate satisfying the following conditions 1 and 2. <Condition 1> A first sample measuring 20 mm short sides x 100 mm long sides is cut out from the optical laminate. The first sample is set in a tensile tester with a chuck distance of 50 mm. When the first sample is pulled in the long side direction at 130°C and a tensile speed of 50 mm / min, the elongation of the first sample at the upper yield point is 6.5% or more. <Condition 2> The average thickness of the low refractive index layer before stretching the optical laminate is designated as t1. A second sample measuring 20 mm short sides x 100 mm long sides is cut out from the optical laminate. Marked lines are marked at 50 mm intervals on the second sample, and the second sample is then preheated at 130°C for 2 minutes. The second sample after preheating is quickly set in a tensile tester. The chuck distance of the tensile tester is adjusted to the distance between the gauge lines after preheating. The second sample is pulled in the long side direction at 130°C and a pulling speed of 50 mm / min, and pulling is stopped when the chuck distance reaches 60 mm. The second sample is removed from the tensile tester and left at 23°C for 120 minutes, after which the thickness of the low refractive index layer of the second sample after stretching is measured. The average thickness of the low refractive index layer after stretching is designated as t2. The ratio of the thickness of the low refractive index layer after stretching to the thickness of the low refractive index layer before stretching, calculated using the following formula, is 80% or more and 99% or less. Ratio (%) of the thickness of the low refractive index layer after stretching to the thickness of the low refractive index layer before stretching = (t2 / t1) × 100 (2) An anti-reflective article comprising a member and the optical laminate according to (1) placed on the member, the surface of the optical laminate facing the low refractive index layer facing away from the member. (3) A panel having a display element and an optical film placed on the light emission surface side of the display element, the optical film including the optical laminate according to (1), the surface of the optical laminate facing the low refractive index layer facing away from the display element. (4) An image display device comprising the panel according to (3).

[0008] The optical laminate of the present disclosure can provide good antireflection properties even when applied to a member having a non-flat shape. The antireflection article, panel, and image display device of the present disclosure can provide good antireflection properties even when the shape of these is non-flat.

[0009] 1 is a schematic cross-sectional view showing an embodiment of an optical laminate of the present disclosure. FIG. 2 is a cross-sectional view showing an embodiment of a panel of the present disclosure. FIG. 3 is a plan view for explaining second and third samples used under conditions 2 and 3.

[0010] Hereinafter, embodiments of the present disclosure will be described.

[0011] [Optical Laminate] The optical laminate of the present disclosure is an optical laminate having a hard coat layer and a low refractive index layer, in this order, on a resin substrate, and satisfies the following conditions 1 and 2. <Condition 1> A first sample measuring 20 mm short side x 100 mm long side is cut out from the optical laminate. The first sample is set in a tensile tester with a chuck distance of 50 mm. When the first sample is pulled in the long side direction at 130°C and a tensile speed of 50 mm / min, the elongation of the first sample at the upper yield point is 6.5% or more. <Condition 2> The average thickness of the low refractive index layer before stretching the optical laminate is designated as t1. A second sample measuring 20 mm short side x 100 mm long side is cut out from the optical laminate. Marked lines are made at 50 mm intervals on the second sample, and then the second sample is preheated at 130°C for 2 minutes. After preheating, the second sample is quickly set in the tensile tester. The distance between the chucks of the tensile tester is adjusted to the distance between the benchmark lines after preheating is completed. The second sample is pulled in the long side direction at 130°C and a pulling speed of 50 mm / min, and pulling is stopped when the distance between the chucks reaches 60 mm. The second sample is removed from the tensile tester and left at 23°C for 120 minutes, after which the thickness of the low refractive index layer of the second sample after stretching is measured. The average thickness of the low refractive index layer after stretching is designated as t2. The ratio of the thickness of the low refractive index layer after stretching to the thickness of the low refractive index layer before stretching, calculated using the following formula, is 80% or more and 99% or less. Ratio (%) of the thickness of the low refractive index layer after stretching to the thickness of the low refractive index layer before stretching = (t2 / t1) × 100

[0012] FIG. 1 is a schematic cross-sectional view of the cross-sectional shape of an optical laminate 100 according to the present disclosure. The optical laminate 100 of FIG. 1 has a hard coat layer 20 and a low refractive index layer 40, in this order, on a resin substrate 10. The optical laminate 100 of FIG. 1 further has a high refractive index layer 30 between the hard coat layer 20 and the low refractive index layer 40. FIG. 1 is a schematic cross-sectional view. That is, in FIG. 1, the scale of each layer constituting the optical laminate 100 is simplified for ease of illustration and differs from the actual scale. The same applies to other drawings such as FIG. 2.

[0013] The optical laminate of the present disclosure is not limited to the layer configuration shown in Fig. 1. For example, the optical laminate of the present disclosure may have other layers not shown in Fig. 1.

[0014] <Condition 1> Condition 1 stipulates that the elongation at the upper yield point of the first sample is 6.5% or more. The elongation at the upper yield point of the first sample can be considered as the elongation at the upper yield point of the optical laminate. In other words, the optical laminate of the present disclosure is required to have an elongation at the upper yield point of 6.5% or more.

[0015] If the elongation at the upper yield point is less than 6.5%, it becomes difficult to apply the optical laminate to a member having a non-flat shape. The elongation at the upper yield point is preferably 6.7% or more, more preferably 6.9% or more, and even more preferably 7.0% or more.

[0016] The hard coat layer has a significant effect on the upper yield point of the optical laminate. On the other hand, the low refractive index layer and the high refractive index layer have little effect on the upper yield point due to their thin thickness. For this reason, lowering the crosslink density of the hard coat layer or reducing the thickness of the hard coat layer tends to increase the elongation at the upper yield point. However, lowering the crosslink density of the hard coat layer or reducing the thickness of the hard coat layer reduces the surface hardness of the hard coat layer, which tends to reduce the surface hardness of the optical laminate. A decrease in the surface hardness of the optical laminate tends to reduce the scratch resistance of the optical laminate. For this reason, the elongation at the upper yield point is preferably 17.0% or less, more preferably 15.0% or less, and even more preferably 12.0% or less.

[0017] In the constituent elements shown in this specification, when multiple upper limit and lower limit options are shown, it is assumed that the range described is a combination of one selected from the upper limit options and one selected from the lower limit options. For example, examples of the range of elongation at the upper yield point include 6.5% to 17.0%, 6.5% to 15.0%, 6.5% to 12.0%, 6.7% to 17.0%, 6.7% to 15.0%, 6.7% to 12.0%, 7.0% to 17.0%, 7.0% to 15.0%, and 7.0% to 12.0%.

[0018] More specifically, condition 1 is measured in the following steps A1 to A6. A1: A first sample measuring 20 mm short side x 100 mm long side is cut out from the optical laminate. Ten samples are prepared. A2: The first sample is set in a tensile tester with a chuck distance of 50 mm. At this time, both ends of the short side of the first sample are fixed with a pair of chucks of the tensile tester. A3: The first sample is heated to 130°C. In the above step A3, the first sample can be heated, for example, by a heating system provided in the tensile tester.

[0019] A4: With both first ends fixed, the first sample is pulled at 130°C and a pulling rate of 50 mm / min to apply strain to the first sample. A5: The upper yield point and the elongation at the upper yield point are calculated from a stress-strain curve with the elongation of the first sample on the horizontal axis and the tensile stress on the vertical axis.

[0020] In this specification, the term "upper yield point" refers to the point at which the "tensile yield strain" of JIS K7161: 2014 occurs. In other words, in this specification, the term "upper yield point" refers to the initial point at which the strain increases without an accompanying increase in stress.

[0021] A6: A2 to A5 are carried out on 10 samples. The average value of the elongations at the upper yield point of the 10 samples is taken as the elongation at the upper yield point of the optical laminate.

[0022] The tensile tester used is one capable of controlling the temperature.

[0023] In this specification, the elongation at the upper yield point is calculated by the following formula. In the formula, the "distance between chucks before tension" is 50 mm when the first sample is set in the tensile tester. The temperature when the first sample is set in the tensile tester is 23°C. Elongation at the upper yield point (%) = {(distance between chucks at the upper yield point - distance between chucks before tension) / distance between chucks before tension} x 100

[0024] The "load at the upper yield point" described later is the stress (N) at the upper yield point, calculated by multiplying the area of ​​the sample located between the chucks before tension (1000 mm ２ ) can be calculated by dividing by

[0025] In order to easily satisfy condition 1, it is preferable to use a resin substrate that is easy to stretch and to adjust the crosslink density and thickness of the hard coat layer. Detailed methods will be described in the embodiments of the resin substrate and the hard coat layer.

[0026] The load at the upper yield point measured under condition 1 was 7.0 mN / mm ２ Preferably, it is 6.0 mN / mm or less. ２ More preferably, it is 5.0 mN / mm or less.２ It is more preferable that the load is 7.0 mN / mm or less. ２ By setting the load to 1.6 mN / mm or less, it is possible to improve the workability when applying the optical laminate to a member with a non-flat shape. If the load is too small, the scratch resistance of the optical laminate is likely to decrease. Therefore, the load is set to 1.6 mN / mm or less. ２ It is preferable that the resistance is 2.0 mN / mm or more. ２ More preferably, it is equal to or greater than this.

[0027] <Condition 2> Condition 2 stipulates that the ratio of the thickness of the low refractive index layer after stretching to the thickness of the low refractive index layer before stretching is 80% or more and 99% or less.

[0028] In this specification, the "ratio of the thickness of the low refractive index layer after stretching to the thickness of the low refractive index layer before stretching" may be referred to as the "ratio of the thickness of the low refractive index layer before and after stretching." In this specification, the "ratio of the thickness of the high refractive index layer after stretching to the thickness of the high refractive index layer before stretching" may be referred to as the "ratio of the thickness of the high refractive index layer before and after stretching."

[0029] The optical laminate is applied to a non-flat member by laminating the optical laminate to the non-flat member while stretching it. Furthermore, during the application described above, the optical laminate is heated to a predetermined temperature to facilitate stretching. Under condition 2, a second sample prepared from the optical laminate is stretched by 10 mm at 130°C, which can be said to reproduce the state in which the optical laminate is applied to a non-flat member. (Note: Under condition 2, the initial gauge line distance is 50 mm. The second sample is then set with the chuck distance adjusted to the gauge line distance, and then stretched until the chuck distance reaches 60 mm. Therefore, under condition 2, the second sample is stretched by 10 mm, which is the difference between 60 mm and 50 mm.) Furthermore, under condition 2, the thickness of the low refractive index layer after stretching is measured after leaving it at 23°C for 120 minutes, which can be said to be measured in a state in which the physical properties changed by heating are stable. Therefore, it can be said that condition 2 reproduces the state in which the optical laminate is applied to a member with a non-flat shape and the state after the optical laminate has stabilized. Therefore, it can be said that the "ratio of the thickness of the low refractive index layer before and after elongation" in condition 2 indicates the "ratio of the thickness of the low refractive index layer before and after applying the optical laminate to a member with a non-flat shape." Similarly, it can be said that the "ratio of the thickness of the high refractive index layer before and after elongation" in condition 3 described below indicates the "ratio of the thickness of the high refractive index layer before and after applying the optical laminate to a member with a non-flat shape."

[0030] In condition 2, a thickness change rate of less than 80% means that the thickness of the low refractive index layer becomes too thin after the optical laminate is applied to a member having a non-flat shape. Therefore, in condition 2, if the thickness change rate is less than 80%, it is not possible to achieve good antireflection properties when applied to a member having a non-flat shape.

[0031] Under Condition 2, the gauge length is stretched from 50 mm to 60 mm, resulting in a 20% elongation in the stretched portion. Therefore, simply considered, the thickness of the second sample decreases by 20% after stretching, and the ratio of the low refractive index layer thickness before and after stretching is approximately 80%. However, for the following reasons, the ratio of the low refractive index layer thickness before and after stretching is usually greater than 80%. First, when the low refractive index layer contains large particles such as hollow particles, the thickness of the area where the large particles are present is unlikely to change during stretching (on the other hand, areas where no large particles are present tend to become thinner due to the stretching of the binder resin). Furthermore, the hard coat layer usually contains a crosslinkable resin. Therefore, when the optical laminate is applied to a non-flat member while being heated, crosslinking of the unreacted crosslinkable resin in the hard coat layer progresses. As the crosslinking of the hard coat layer progresses, the hard coat layer shrinks, and the low refractive index layer also shrinks due to the influence of the thick hard coat layer. The thickness of the low-refractive index layer increases according to the degree of shrinkage. Therefore, the thickness change rate of the low-refractive index layer of the second sample is greater than 80%. Furthermore, the greater the thickness change rate of the low-refractive index layer is, the greater the degree of increase in the thickness of the low-refractive index layer due to the shrinkage of the hard coat layer. When the low-refractive index layer shrinks and its thickness increases, cracks tend to occur in the low-refractive index layer and the arrangement of the hollow particles tends to become disordered. Therefore, when the low-refractive index layer shrinks and its thickness increases significantly, its physical properties tend to change. Therefore, under condition 2, a thickness change rate exceeding 99% means that the thickness change rate of the low-refractive index layer increases more than the theoretical value of 80% due to the shrinkage of the hard coat layer. A low-refractive index layer with such a large increase in thickness is prone to cracks and disorder of the hollow particles, as described above, and therefore does not provide good antireflection properties. Therefore, under condition 2, a thickness change rate exceeding 99% does not provide good antireflection properties when applied to a non-flat component.

[0032] In condition 2, the change rate of the thickness of the low refractive index layer before and after stretching is preferably 82% or more and 97% or less, more preferably 84% or more and 95% or less, and even more preferably 86% or more and 93% or less.

[0033] More specifically, condition 2 is measured according to the following procedures B1 to B7: B1: The average thickness of the low refractive index layer before stretching the optical laminate is defined as t1.

[0034] In this specification, the average thickness t1 of the low refractive index layer before stretching the optical laminate is measured by the following procedures (a1) and (a2): (a1) A sample for film thickness measurement is prepared, in which the cross section of the optical laminate is exposed. (a2) Two locations of the cross section of the sample are imaged using an STEM. From each of the two images, the thicknesses of the low refractive index layer are extracted at five locations, for a total of 10 thicknesses. The thicknesses at the 10 locations are averaged to calculate the average thickness t1 of the low refractive index layer.

[0035] In this specification, the average thickness t3 of the high refractive index layer before stretching the optical laminate and the average thickness t5 of the hard coat layer before stretching the optical laminate are calculated by replacing the "low refractive index layer" in (a2) above with the "high refractive index layer" or the "hard coat layer."

[0036] A sample in which the cross section of the optical laminate (a1) is exposed is prepared by the following steps X1 to X2. X1: The optical laminate and a black plate are bonded together via an optically transparent adhesive sheet, and then cut to a desired size to prepare a cut sample. The size of the cut sample is, for example, a strip of 10 mm length x 3 mm width.

[0037] X2: The cut sample is cut vertically to produce a sliced ​​sample that exposes the cross section of the optical laminate. The cut sample is cut with a microtome using a glass knife and a diamond knife. When cutting the cut sample with a microtome, first roughly cut it with a glass knife to produce a surface approximately 100 μm long x 20 μm wide that includes the cross section of the coated surface (rough trimming). Finally, this surface is cut with a diamond knife, and the slice floated on water is collected with a mesh.

[0038] B2: A second sample measuring 20 mm on the short side and 100 mm on the long side is cut out from the optical laminate.

[0039] B3: Mark the second sample with marks spaced 50 mm apart, then preheat it at 130°C for 2 minutes. After preheating, quickly set the second sample in a tensile tester. The distance between the chucks of the tensile tester is adjusted to the distance between the marks after preheating.

[0040] In step B3, the temperature when marking the second sample with 50 mm intervals is 23°C. In step B3, after marking the second sample with 50 mm intervals, the sample is preheated at 130°C for 2 minutes. Preheating at the same temperature as step B4 prevents the sample from elongating due to residual heat after step B4. This reduces fluctuations in the thickness of the low refractive index layer due to elongation due to residual heat after step B4. In step B3, before placing the preheated second sample in the tensile tester, heat-resistant tape is wrapped around both ends of the long sides of the preheated second sample ( FIG. 3 ). The heat-resistant tape is wrapped outside the marked lines. In FIG. 3 , the portion indicated by the symbol 201 indicates the portion where the heat-resistant tape is wrapped. In FIG. 3 , the symbol L corresponds to the distance between the marked lines after preheating. When placing the second sample in the tensile tester, the portion of the second sample where the heat-resistant tape is wrapped is fixed with a pair of chucks of the tensile tester.

[0041] B4: Heat the second sample to 130° C. In B4, the second sample can be heated, for example, by a heating system provided in the tensile tester. It is preferable to heat the second sample quickly.

[0042] B5: The second sample is pulled in the long side direction at 130°C and a pulling speed of 50 mm / min, and the pulling is stopped when the chuck distance reaches 60 mm. In B5, the tensile tester is set to operating conditions such that the pulling is stopped when the chuck distance reaches 60 mm and the chuck does not return to the origin position.

[0043] B6: The second sample is removed from the tensile tester and left to stand at 23° C. for 120 minutes, and then the thickness of the low refractive index layer of the second sample after stretching is measured. The average thickness of the low refractive index layer after stretching is designated as t2.

[0044] In B6, the average thickness t2 of the low refractive index layer after stretching the optical laminate is measured by the following procedures (b1) and (b2). (b1) A sample for film thickness measurement is prepared from the second sample left at 23°C for 120 minutes, with the cross section of the optical laminate exposed. The sample is preferably obtained from the area "S" in Figure 3. (b2) Two locations of the cross section of the sample are imaged using an STEM. Thicknesses of the low refractive index layer after stretching are extracted from five locations on each of the two images, for a total of 10 thicknesses. The thicknesses at the 10 locations are averaged to calculate the average thickness t2 of the low refractive index layer after stretching.

[0045] The sample (b1) in which the cross section of the optical laminate is exposed can be prepared, for example, by the same procedure as in the above X1 and X2.

[0046] B7: The ratio of the thickness of the low refractive index layer after stretching to the thickness of the low refractive index layer before stretching is calculated using the following formula: Ratio (%) of the thickness of the low refractive index layer after stretching to the thickness of the low refractive index layer before stretching = (t2 / t1) x 100

[0047] In condition 2, a tensile tester capable of controlling temperature is used.

[0048] In Condition 2 and Condition 3 described later, the atmosphere in which t1, t2, t3, and t4 are measured is 23° C. and a relative humidity of 50%.

[0049] In order to facilitate satisfaction of condition 2 and condition 3 described below, it is preferable to adjust the functional group equivalent of the ionizing radiation curable resin composition forming the hard coat layer, or to adjust the average particle size and content of the hollow particles in the low refractive index layer. Detailed adjustment methods will be described in the embodiments of each constituent requirement.

[0050] The optical laminate preferably has a high refractive index layer between the hard coat layer and the low refractive index layer.

[0051] The optical laminate preferably further satisfies the following condition 3. <Condition 3> The average thickness of the high refractive index layer before stretching the optical laminate is defined as t3. A third sample measuring 20 mm short side x 100 mm long side is cut out from the optical laminate. Marked lines at 50 mm intervals are then made on the third sample, which is then preheated at 130°C for 2 minutes. After preheating, the third sample is quickly set in a tensile tester. The distance between the chucks of the tensile tester is adjusted to the distance between the marked lines after preheating. The third sample is pulled in the long side direction at 130°C and a pulling speed of 50 mm / min, and pulling is stopped when the distance between the chucks reaches 60 mm. The third sample is removed from the tensile tester and left at 23°C for 120 minutes, after which the thickness of the high refractive index layer of the third sample after stretching is measured. The average thickness of the high refractive index layer after stretching is defined as t4. The ratio of the thickness of the high refractive index layer after stretching to the thickness of the high refractive index layer before stretching, calculated by the following formula, is 80% or more and 99% or less: ratio (%) of the thickness of the high refractive index layer after stretching to the thickness of the high refractive index layer before stretching = (t4 / t3) × 100

[0052] In condition 3, a thickness change rate of 80% or more means that the thickness of the high refractive index layer does not become too thin after the optical laminate is applied to a member with a non-flat shape. In condition 3, a thickness change rate of 99% or less means that the thickness change rate of the high refractive index layer does not increase significantly above the theoretical value of 90% due to the influence of shrinkage of the hard coat layer. Therefore, by having a high refractive index layer between the hard coat layer and the low refractive index layer and satisfying condition 3, the optical laminate can more easily achieve good antireflection properties when applied to a member with a non-flat shape.

[0053] In condition 3, the thickness change rate of the high refractive index layer before and after stretching is preferably 82% or more and 97% or less, more preferably 84% or more and 95% or less, and even more preferably 86% or more and 93% or less.

[0054] More specifically, condition 3 is measured according to the following procedures C1 to C7.

[0055] C1: The average thickness of the high refractive index layer before stretching the optical laminate is defined as t3. In the above C1, t3 can be measured by the procedure described above.

[0056] C2: A third sample measuring 20 mm on the short side and 100 mm on the long side is cut out from the optical laminate. The third sample can be used in combination with the second sample. If the third sample is used in combination with the second sample, the following steps C2 to C5 can be used in combination with the steps B2 to B5.

[0057] C3: Mark the third sample with marks spaced 50 mm apart, then preheat at 130°C for 2 minutes. After preheating, the third sample is quickly set in a tensile tester. The distance between the chucks of the tensile tester is adjusted to the distance between the marks after preheating. In C3 above, the temperature when marking the third sample with marks spaced 50 mm apart is 23°C. Specific embodiments for preheating the third sample and for setting the third sample in the tensile tester are the same as the corresponding embodiments for the second sample.

[0058] C4: The third sample is heated to 130° C. C5: The third sample is pulled in the longitudinal direction at 130° C. and a pulling speed of 50 mm / min, and the pulling is stopped when the chuck distance reaches 60 mm. Specific embodiments of C4 and C5 are the same as those of B4 and B5.

[0059] C6: The third sample is removed from the tensile tester and left at 23°C for 120 minutes, after which the thickness of the high refractive index layer of the third sample after stretching is measured. The average thickness of the high refractive index layer after stretching is designated as t4. In this specification, the average thickness t4 of the high refractive index layer after stretching the optical laminate is measured by replacing the "second sample" and "low refractive index layer" with the "third sample" and "high refractive index layer" in the procedures (b1) and (b2), respectively.

[0060] C7: The ratio of the thickness of the high refractive index layer after stretching to the thickness of the high refractive index layer before stretching is calculated using the following formula: Ratio (%) of the thickness of the high refractive index layer after stretching to the thickness of the high refractive index layer before stretching = (t4 / t3) x 100

[0061] If the optical laminate has a high refractive index layer between the hard coat layer and the low refractive index layer but does not satisfy condition 3, it is difficult to achieve good antireflection properties when applied to a member having a non-flat shape. This is because, when the optical laminate has a high refractive index layer and a low refractive index layer, the balance between the thicknesses of the high refractive index layer and the low refractive index layer becomes important.

[0062] The absolute value of the difference between the thickness ratio of the condition 2 and the thickness ratio of the condition 3 is preferably 3% or less, and more preferably 2% or less. By setting the absolute value of the difference to 3% or less, the balance of the thicknesses of the high refractive index layer and the low refractive index layer is maintained, which makes it easier to improve the antireflection properties when applied to a member with a non-flat shape.

[0063] In this specification, reflectance refers to the luminous reflectance Y value measured based on the specularly reflected light of incident light when light is incident on the sample from a direction of 5 degrees, with the direction perpendicular to the surface of the low refractive index layer side of the sample made from the optical laminate being 0 degrees.

[0064] <Resin substrate> The resin substrate preferably has good light transmittance, is easily stretchable, and has excellent moldability. The resin constituting the resin substrate is not particularly limited, but in order to easily satisfy condition 1, a resin selected from the group consisting of carbonate resin, (meth)acrylic resin, olefin resin, and ABS resin is preferred. That is, the resin substrate is preferably a carbonate resin substrate, a (meth)acrylic resin substrate, an olefin resin substrate, or an ABS resin substrate. The (meth)acrylic resin substrate is more preferred because it is easy to improve adhesion with the hard coat layer. The resin substrate may contain additives such as rubber particles to improve moldability. In this specification, "(meth)acrylic" is a general term for "acrylic" and "methacrylic."

[0065] Examples of (meth)acrylic resins include homopolymers or copolymers of (meth)acrylic acid esters and copolymers of (meth)acrylic acid esters and comonomers. Examples of (meth)acrylic acid esters include methyl (meth)acrylate, ethyl (meth)acrylate, butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, hydroxyethyl (meth)acrylate, hydroxypropyl (meth)acrylate, dimethylaminoethyl (meth)acrylate, and glycidyl (meth)acrylate. Examples of comonomers include vinyl acetate, (meth)acrylonitrile, (meth)acrylamide, styrene, (meth)acrylic acid, itaconic acid, and maleic anhydride. The (meth)acrylic resin may be modified with fluorine.

[0066] Specific examples of the (meth)acrylic resin include polyalkyl (meth)acrylates such as polymethyl (meth)acrylate, polyethyl (meth)acrylate, polypropyl (meth)acrylate, and polybutyl (meth)acrylate. Of these, polymethyl (meth)acrylate is preferred.

[0067] The thickness of the resin substrate is preferably 5 μm or more and 150 μm or less, more preferably 20 μm or more and 100 μm or less, and even more preferably 30 μm or more and 50 μm or less. By making the thickness of the resin substrate 5 μm or more, the handleability of the optical laminate can be easily improved. By making the thickness of the resin substrate 150 μm or less, the moldability of the optical laminate can be easily improved.

[0068] The thickness of the resin substrate can be measured using a general-purpose film thickness measuring device. The thickness of the resin substrate may be measured at any 10 points and the average value thereof is the above-mentioned value.

[0069] To improve adhesion, the surface of the resin substrate may be subjected to a physical treatment such as corona discharge treatment or a chemical treatment, or an easy-adhesion layer may be formed on the surface. The resin substrate preferably has a total light transmittance according to JIS K7361-1:1997 of 70% or more, more preferably 80% or more, and even more preferably 85% or more.

[0070] <Hard Coat Layer> The optical laminate of the present disclosure is required to have a hard coat layer on the resin substrate. By having a hard coat layer, the scratch resistance of the optical laminate can be easily improved.

[0071] The hard coat layer preferably contains, as a main component, a cured product of a curable resin composition such as a thermosetting resin composition or an ionizing radiation-curable resin composition, and more preferably contains, as a main component, a cured product of an ionizing radiation-curable resin composition. The main component means that the hard coat layer comprises 50% by mass or more of the resin components constituting the hard coat layer, preferably 70% by mass or more, more preferably 90% by mass or more, and even more preferably 99% by mass or more.

[0072] A thermosetting resin composition is a composition containing at least a thermosetting resin, and is a resin composition that cures when heated. Examples of thermosetting resins include acrylic resins, urethane resins, phenolic resins, urea-melamine resins, epoxy resins, unsaturated polyester resins, and silicone resins. In a thermosetting resin composition, a curing agent is added to the curable resin as needed.

[0073] The ionizing radiation-curable resin composition is a composition containing a compound having an ionizing radiation-curable functional group (hereinafter also referred to as "ionizing radiation-curable compound"). Examples of the ionizing radiation-curable functional group include ethylenically unsaturated bond groups such as (meth)acryloyl groups, vinyl groups, and allyl groups, as well as epoxy groups and oxetanyl groups. The ionizing radiation-curable compound is preferably a compound having an ethylenically unsaturated bond group, and more preferably a compound having a (meth)acryloyl group. The compound having a (meth)acryloyl group is preferably a (meth)acrylate-based compound. The ionizing radiation refers to electromagnetic waves or charged particle beams that have an energy quantum capable of polymerizing or crosslinking molecules. Typically, ultraviolet (UV) or electron beams (EB) are used, but other types of electromagnetic waves such as X-rays and gamma rays, as well as charged particle beams such as alpha rays and ion beams, can also be used.

[0074] The (meth)acrylate compound may be a monomer or an oligomer. It is preferable to mix a plurality of (meth)acrylate compounds to easily satisfy conditions 1 and 2 while maintaining the hardness of the hard coat layer. For example, it is preferable to mix the following (meth)acrylate compounds (1) to (3).

[0075] (1) (meth)acrylate monomers having 3 or more functional groups; (2) (meth)acrylate oligomers having an average number of functional groups of 3 or more; and (3) (meth)acrylate monomers having 1 or 2 functional groups. In the above (1) to (3), the number of functional groups refers to the number of (meth)acryloyl groups.

[0076] The monomer (1) above plays a role in increasing the hardness of the hard coat layer. However, if the amount of the monomer (1) above is too large, it may be difficult to satisfy conditions 1 and 2, or the load at the upper yield point measured under condition 1 may become too large. If the amount of the monomer (1) above is too small, the hardness of the hard coat layer may decrease, or the elongation of condition 1 may become too large. The oligomer (2) above plays a role in making it easier to satisfy conditions 1 and 2 while maintaining the hardness of the hard coat layer. If only the monomer (1) above is used as the (meth)acrylate-based compound, it is difficult to easily satisfy conditions 1 and 2 while maintaining the hardness of the hard coat layer. By including an appropriate amount of the oligomer (2) above, it is possible to easily satisfy conditions 1 and 2 while maintaining the hardness of the hard coat layer. The monomer (3) above plays a role in suppressing excessive crosslinking of the hard coat layer. Furthermore, by including the monomer (3) as the (meth)acrylate compound, conditions 1 and 2 can be easily satisfied, and the load at the upper yield point measured under condition 1 can be easily reduced. Furthermore, the monomer (3) can easily improve adhesion to a resin substrate (particularly a (meth)acrylic resin substrate). However, if the amount of the monomer (3) is too large, the hardness of the hard coat layer may decrease, or the elongation of condition 1 may become too large.

[0077] Based on the total amount of the ionizing radiation-curable resin composition, the mass proportion of the (1) (meth)acrylate monomer having an average functionality of 3 or more is preferably 1% by mass or more and 45% by mass or less, and more preferably 10% by mass or more and 35% by mass or less. Based on the total amount of the ionizing radiation-curable resin composition, the mass proportion of the (2) (meth)acrylate oligomer having an average functionality of 3 or more is preferably 20% by mass or more and 85% by mass or less, and more preferably 35% by mass or more and 60% by mass or less. Based on the total amount of the ionizing radiation-curable resin composition, the mass proportion of the (3) (meth)acrylate monomer having an average functionality of 1 or 2 is preferably 10% by mass or more and 50% by mass or less, and more preferably 20% by mass or more and 40% by mass or less.

[0078] When R1 (mass %) is defined as the mass proportion of the (meth)acrylate monomer having an average functionality of 3 or more (1) relative to the total amount of the ionizing radiation curable resin composition, R2 (mass %) is defined as the mass proportion of the (meth)acrylate oligomer having an average functionality of 3 or more (2) relative to the total amount of the ionizing radiation curable resin composition, R3 (mass %) is defined as the mass proportion of the (meth)acrylate monomer having one or two functionality (3) relative to the total amount of the ionizing radiation curable resin composition, and t5 (μm) is defined as the average thickness of the hard coat layer before stretching the optical laminate, it is preferable to satisfy the following conditions E1 to E3. By satisfying the following conditions E1 to E3, conditions 1 and 2 can be more easily satisfied. <Condition E1> 55≦R1×t5≦600 <Condition E2> 150≦R2×t5≦1150 <Condition E3> 70≦R3×t5≦400

[0079] In the condition E1, R1×t5 is preferably 60 or more and 310 or less, and more preferably 70 or more and 180 or less. In the condition E2, R2×t5 is preferably 150 or more and 800 or less, and more preferably 180 or more and 500 or less. In the condition E3, R3×t5 is preferably 75 or more and 350 or less, and more preferably 130 or more and 232 or less.

[0080] The number of functional groups of the (meth)acrylate monomer in (1) above is preferably 3 to 8, more preferably 3 to 6. By making the number of functional groups 3 or more, it is possible to easily improve scratch resistance. By making the number of functional groups 8 or less, it is possible to easily satisfy conditions 1 and 2 while maintaining the hardness of the hard coat layer.

[0081] Examples of trifunctional or higher functional (meth)acrylate monomers include trimethylolpropane tri(meth)acrylate, pentaerythritol tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, dipentaerythritol hexa(meth)acrylate, dipentaerythritol tetra(meth)acrylate, and isocyanuric acid-modified tri(meth)acrylate. The (meth)acrylate monomers may have a portion of their molecular skeleton modified. For example, the (meth)acrylate monomers may have a portion of their molecular skeleton modified with ethylene oxide, propylene oxide, caprolactone, isocyanuric acid, alkyl, cyclic alkyl, aromatic, bisphenol, or the like.

[0082] The average number of functional groups of the (meth)acrylate oligomer (2) is preferably 3 or more and 8 or less, more preferably 3 or more and 6 or less. By making the average number of functional groups 3 or more, it is possible to easily improve scratch resistance. By making the average number of functional groups 8 or less, it is possible to easily satisfy conditions 1 and 2 while maintaining the hardness of the hard coat layer.

[0083] Examples of (meth)acrylate oligomers include acrylate polymers such as urethane (meth)acrylate, epoxy (meth)acrylate, polyester (meth)acrylate, and polyether (meth)acrylate. Urethane (meth)acrylate can be obtained, for example, by reacting a polyhydric alcohol and an organic diisocyanate with a hydroxy (meth)acrylate. Preferred epoxy (meth)acrylates include (meth)acrylates obtained by reacting a trifunctional or higher aromatic epoxy resin, alicyclic epoxy resin, aliphatic epoxy resin, or the like with (meth)acrylic acid, (meth)acrylates obtained by reacting a difunctional or higher aromatic epoxy resin, alicyclic epoxy resin, aliphatic epoxy resin, or the like with a polybasic acid and (meth)acrylic acid, and (meth)acrylates obtained by reacting a difunctional or higher aromatic epoxy resin, alicyclic epoxy resin, aliphatic epoxy resin, or the like with a phenol and (meth)acrylic acid.

[0084] The weight average molecular weight of the (meth)acrylate oligomer (2) above is preferably from 500 to 3000, more preferably from 600 to 2000, and even more preferably from 700 to 1200. In this specification, the number average molecular weight and weight average molecular weight are average molecular weights measured by GPC analysis and converted into standard polystyrene.

[0085] The (meth)acrylate monomer having one or two functional groups in (3) above may be a (meth)acrylate monomer having one functional group, a (meth)acrylate monomer having two functional groups, or a combination of both. In order to easily satisfy conditions 1 and 2 while maintaining the hardness of the hard coat layer, it is preferable to contain only a (meth)acrylate monomer having one functional group.

[0086] Examples of bifunctional (meth)acrylate monomers include ethylene glycol di(meth)acrylate, bisphenol A tetraethoxydiacrylate, bisphenol A tetrapropoxydiacrylate, 1,6-hexanediol diacrylate, etc. Examples of monofunctional (meth)acrylates include methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, butyl (meth)acrylate, pentyl (meth)acrylate, hexyl (meth)acrylate, cyclohexyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, lauryl (meth)acrylate, stearyl (meth)acrylate, and isobornyl (meth)acrylate.

[0087] When the ionizing radiation-curable compound is an ultraviolet-curable compound, the coating liquid for the hard coat layer preferably contains additives such as a photopolymerization initiator and a photopolymerization accelerator. Examples of the photopolymerization initiator include one or more selected from acetophenone, benzophenone, α-hydroxyalkylphenone, Michler's ketone, benzoin, benzyl dimethyl ketal, benzoyl benzoate, α-acyloxime ester, α-aminoalkylphenone, thioxanthones, etc. The photopolymerization accelerator can reduce polymerization inhibition by air during curing and increase the curing rate, and examples thereof include one or more selected from p-dimethylaminobenzoic acid isoamyl ester, p-dimethylaminobenzoic acid ethyl ester, etc.

[0088] The lower limit of the thickness of the hard coat layer is preferably 2.5 μm or more, more preferably 4.0 μm or more, and even more preferably 5.0 μm or more, and the upper limit is preferably 13.5 μm or less, more preferably 12.0 μm or less, and even more preferably 10.0 μm or less. "The thickness of the hard coat layer" refers to the above-mentioned "average thickness t5 of the hard coat before stretching the optical laminate." By making the thickness of the hard coat layer 2.5 μm or more, it is possible to easily improve scratch resistance. By making the thickness of the hard coat layer 13.5 μm or less, it is possible to easily satisfy condition 1, to easily reduce the load at the upper yield point measured under condition 1, and to easily suppress an excessive increase in internal haze.

[0089] The hard coat layer may further contain additives such as a matting agent, a leveling agent, an antifouling agent, an antistatic agent, an antioxidant, a surfactant, a dispersant, an ultraviolet absorber, and a light stabilizer.

[0090] The hard coat layer can be formed, for example, by applying a coating liquid for hard coat layer containing materials for forming the hard coat layer and a solvent onto a resin substrate, drying the coating liquid, and then irradiating the coating liquid with ionizing radiation as necessary.

[0091] <Low Refractive Index Layer> The optical laminate of the present disclosure is required to have a low refractive index layer. The low refractive index layer is preferably located on the surface of the hard coat layer opposite to the resin substrate.

[0092] The low refractive index layer preferably contains a binder resin and hollow particles, and more preferably further contains solid particles.

[0093] <<Binder Resin>> The low refractive index layer preferably contains a cured product of a curable resin composition as a binder resin. The curable resin composition is a composition containing a curable compound such as a thermosetting resin or an ionizing radiation curable compound. The proportion of the cured product of the curable resin composition to the total binder resin in the low refractive index layer is preferably 50% by mass or more, more preferably 70% by mass or more, more preferably 90% by mass or more, and most preferably 100% by mass. Examples of the curable resin composition for the low refractive index layer include a thermosetting resin composition or an ionizing radiation curable resin composition, and an ionizing radiation curable resin composition is preferred. That is, the low refractive index layer preferably contains a cured product of an ionizing radiation curable resin composition as a binder resin.

[0094] Examples of the curable resin composition, such as a thermosetting resin composition or an ionizing radiation curable resin composition, include the same as those exemplified for the hard coat layer. The ionizing radiation curable compound used in the low refractive index layer preferably contains a (meth)acrylate compound having three or more (meth)acryloyl groups in order to improve scratch resistance.

[0095] Hollow particles are particles that have an outer shell layer, a cavity surrounded by the outer shell layer, and air contained within the cavity. Hollow particles are particles whose refractive index decreases in proportion to their porosity.

[0096] The material of the outer shell layer of the hollow particles may be either an inorganic compound such as silica or magnesium fluoride, or an organic compound, but silica is preferred from the viewpoint of low refractive index and strength. That is, the low refractive index layer preferably contains hollow silica particles as the hollow particles.

[0097] The hollow particles preferably have an average particle diameter of 55.0 nm or more and 130.0 nm or less, more preferably 60.0 nm or more and 110.0 nm or less, even more preferably 65.0 nm or more and 90.0 nm or less, and even more preferably 70.0 nm or more and 80.0 nm or less. By setting the average particle diameter to 55.0 nm or more, the reflectance of the low refractive index layer can be reduced, making it easier to improve the anti-reflection properties of the optical laminate. By setting the average particle diameter to 130.0 nm or less, it is easier to suppress uneven thickness of the low refractive index layer when the optical laminate is applied to a non-flat member. For the same hollow particle content, reducing the average particle diameter of the hollow particles can increase the number of hollow particles. Furthermore, the hard coat layer is less likely to shrink in areas where large particles such as hollow particles are present. Therefore, by setting the average particle diameter of the hollow particles to 90.0 nm or less, shrinkage of the hard coat layer can be suppressed, making it easier to satisfy condition 2.

[0098] The average particle diameters of hollow particles, solid particles (described later), and high refractive index particles (described later) are calculated by the following steps D1 to D3. D1: The cross section of the antireflection member is imaged using an STEM. The acceleration voltage of the STEM is preferably 10 kV or more and 30 kV or less, and the magnification is preferably 50,000 times or more and 100,000 times or less. D2: All hollow particles in the low refractive index layer contained in one captured image are extracted. The particle diameter of each hollow particle is then calculated. The particle diameter of each hollow particle refers to the distance between two parallel lines that maximize the distance between the cross section of the hollow particle. D3: From all hollow particles whose particle diameters were measured in A2, the lowest 10% of hollow particles are excluded. "%" is based on the number and is rounded off. The average particle diameter of the remaining 90% of hollow particles is the average particle diameter of the hollow particles.

[0099] In the above D3, the reasons for excluding the hollow particles with the lowest particle diameter of 10% are as follows: (1) The hollow particles whose particle diameter is measured as small may be cut at a location away from the center of the hollow particles. (2) The hollow particles whose particle diameter is measured as small may be partially buried in a layer adjacent to the low refractive index layer, such as a high refractive index layer or a hard coat layer.

[0100] In the above steps D1 to D3, if the particles to be extracted are changed to "all solid particles in the low refractive index layer contained in one captured image," the average particle diameter of the solid particles can be calculated. Also, in the above steps D1 to D3, if the particles to be extracted are changed to "all high refractive index particles in the high refractive index layer contained in one captured image," the average particle diameter of the high refractive index particles can be calculated.

[0101] The higher the content of hollow particles, the lower the refractive index of the low refractive index layer. On the other hand, if the content of hollow particles relative to the binder resin is too high, unevenness in the thickness of the low refractive index layer is likely to occur when the optical laminate is applied to a non-flat member. Therefore, the content of hollow particles is preferably 100 parts by mass or more and 300 parts by mass or less, more preferably 120 parts by mass or more and 250 parts by mass or less, and even more preferably 130 parts by mass or more and 200 parts by mass or less, relative to 100 parts by mass of the binder resin.

[0102] In order to suppress aggregation, the surfaces of the hollow particles are preferably coated with a silane coupling agent. The silane coupling agent preferably has a (meth)acryloyl group or an epoxy group, and more preferably has a methacryloyl group.

[0103] The hollow particles may contain two or more types of hollow particles, for example, hollow particles having different outer shell materials or hollow particles having different particle diameters.

[0104] <<Solid Particles>> The low refractive index layer preferably contains solid particles in addition to hollow particles. By containing solid particles in addition to hollow particles, the scratch resistance of the low refractive index layer can be easily improved.

[0105] The material of the solid particles is preferably an inorganic compound such as silica or magnesium fluoride, and more preferably silica.

[0106] The average particle size of the solid particles is preferably smaller than that of the hollow particles. The lower limit of the average particle size of the solid particles is preferably 5 nm or more, more preferably 10 nm or more, and the upper limit is preferably 20 nm or less, more preferably 15 nm or less.

[0107] From the viewpoint of improving scratch resistance, the content of the solid particles is preferably 10 parts by mass or more, more preferably 20 parts by mass or more, per 100 parts by mass of the binder resin. On the other hand, if the content of the solid particles is too high, the solid particles tend to aggregate, and the amount of binder resin covering the hollow particles decreases, which may result in a decrease in scratch resistance. For this reason, the content of the solid particles is preferably 100 parts by mass or less, more preferably 50 parts by mass or less, per 100 parts by mass of the binder resin.

[0108] The lower limit of the thickness of the low refractive index layer is preferably 80 nm or more, more preferably 85 nm or more, and more preferably 90 nm or more, and the upper limit is preferably 150 nm or less, more preferably 110 nm or less, and more preferably 105 nm or less. "The thickness of the low refractive index layer" means the above-mentioned "average thickness t1 of the low refractive index layer before stretching the optical laminate."

[0109] The ratio D / t1, where t1 is the thickness of the low refractive index layer and D is the average particle diameter of the hollow particles, is preferably 0.55 or more and 1.00 or less, more preferably 0.65 or more and 0.95 or less, and even more preferably 0.70 or more and 0.80 or less. By setting D / t1 to 0.55 or more, the refractive index of the low refractive index layer can be easily reduced. By setting D / t1 to 1.00 or less, it is easy to suppress unevenness in the thickness of the low refractive index layer when the optical laminate is applied to a member with a non-flat shape.

[0110] The lower limit of the refractive index of the low refractive index layer is preferably 1.10 or more, more preferably 1.20 or more, more preferably 1.26 or more, more preferably 1.28 or more, and more preferably 1.30 or more, and the upper limit is preferably 1.48 or less, more preferably 1.45 or less, more preferably 1.40 or less, more preferably 1.38 or less, and more preferably 1.35 or less. In this specification, the refractive indexes of the low refractive index layer and the high refractive index layer mean values ​​at a wavelength of 589.3 nm.

[0111] The low refractive index layer may further contain additives such as an antistatic agent, an antioxidant, a surfactant, a dispersant, a light stabilizer, and an ultraviolet absorber.

[0112] The low refractive index layer can be formed by applying a coating liquid for the low refractive index layer containing components constituting the low refractive index layer and a solvent, drying the coating liquid, and, if necessary, curing the coating liquid by irradiating the coating liquid with ionizing radiation.

[0113] <Other Layers> The optical laminate may have other layers such as a high refractive index layer and an antistatic layer. By having a high refractive index layer, the reflectance of the optical laminate can be more easily reduced. The high refractive index layer is preferably provided between the hard coat layer and the low refractive index layer. When the optical laminate has a high refractive index layer, it is preferable that the optical laminate has a resin substrate, a hard coat layer, a high refractive index layer, and a low refractive index layer in this order.

[0114] <High refractive index layer> The high refractive index layer can be formed from a coating liquid for a high refractive index layer containing, for example, a binder resin composition and high refractive index particles. That is, the high refractive index layer preferably contains a binder resin and high refractive index particles.

[0115] The binder resin of the high refractive index layer preferably contains a cured product of a curable resin composition. The ratio of the cured product of the curable resin composition to the total binder resin of the high refractive index layer is preferably 50% by mass or more, more preferably 70% by mass or more, more preferably 90% by mass or more, and most preferably 100% by mass. The curable resin composition of the high refractive index layer includes a heat-curable resin composition or an ionizing radiation-curable resin composition, and an ionizing radiation-curable resin composition is preferred. Examples of curable resin compositions such as a heat-curable resin composition or an ionizing radiation-curable resin composition are the same as those exemplified for the hard coat layer. The ionizing radiation-curable compound used in the high refractive index layer preferably contains a (meth)acrylate compound having three or more (meth)acryloyl groups.

[0116] Examples of high refractive index particles include antimony pentoxide, zinc oxide, titanium oxide, cerium oxide, tin-doped indium oxide, antimony-doped tin oxide, yttrium oxide, and zirconium oxide.

[0117] The average particle size of the high refractive index particles is preferably 2 nm or more, more preferably 5 nm or more, and even more preferably 10 nm or more. From the viewpoints of whitening prevention and transparency, the average particle size of the high refractive index particles is preferably 200 nm or less, more preferably 100 nm or less, more preferably 80 nm or less, more preferably 60 nm or less, and even more preferably 30 nm or less.

[0118] The content of the high refractive index particles is preferably 100 parts by mass or more, more preferably 150 parts by mass or more, and even more preferably 250 parts by mass or more, relative to 100 parts by mass of the binder resin, and the upper limit is preferably 500 parts by mass or less, more preferably 400 parts by mass or less, and even more preferably 350 parts by mass or less.

[0119] The lower limit of the refractive index of the high refractive index layer is preferably 1.53 or more, more preferably 1.54 or more, more preferably 1.55 or more, and more preferably 1.56 or more, and the upper limit is preferably 1.85 or less, more preferably 1.80 or less, more preferably 1.78 or less, and more preferably 1.77 or less.

[0120] The upper limit of the thickness of the high refractive index layer is preferably 200 nm or less, more preferably 185 nm or less, and even more preferably 175 nm or less, and the lower limit is preferably 50 nm or more, more preferably 70 nm or more, and even more preferably 80 nm or more. "The thickness of the high refractive index layer" means the above-mentioned "average thickness t3 of the high refractive index layer before stretching the optical laminate."

[0121] The high refractive index layer may further contain additives such as a leveling agent, an antistatic agent, an antioxidant, a surfactant, a dispersant, a light stabilizer, and an ultraviolet absorber.

[0122] <Pencil Hardness> In order to enhance scratch resistance, the surface of the optical laminate preferably has a pencil hardness of H or more, more preferably 2H or more. The surface means the surface of the optical laminate on the side having the low refractive index layer, with respect to the hard coat layer.

[0123] In this specification, pencil hardness is measured in accordance with JIS K5600-5-4:1999 under conditions of a load of 500 g and a speed of 1.4 mm / sec. Furthermore, pencil hardness tests are performed five times on a sample for measuring pencil hardness, and the hardness when no appearance abnormalities such as scratches are observed four or more times is taken as the pencil hardness value of each sample. For example, if five tests are performed using a 2H pencil and no appearance abnormalities occur four times, the pencil hardness of that sample is 2H. Appearance abnormalities were checked for scratches and dents, excluding discoloration.

[0124] <Optical Properties> The optical laminate preferably has a total light transmittance of 80% or more, more preferably 85% or more, according to JIS K7361-1:1997. The light incident surface when measuring the total light transmittance and haze is the surface on the resin substrate side. In this specification, the total light transmittance means the average value of measurements taken at 10 locations.

[0125] The optical laminate preferably has a haze of 1.0% or less, more preferably 0.8% or less, and even more preferably 0.7% or less, according to JIS K7136:2000. By making the haze 1.0% or less, it is possible to easily improve the resolution of images. The lower limit of the haze is not particularly limited, but is usually 0.1% or more.

[0126] The optical laminate preferably has an internal haze of 0.4% or less, more preferably 0.3% or less. By keeping the internal haze at 0.4% or less, it is easier to improve the image resolution. The internal haze can be measured by a commonly used method, for example, by the following method. (1) A sample is prepared in which the surface irregularities of the optical laminate are smoothed, for example, by laminating a transparent sheet via a transparent adhesive layer to the surface of the optical laminate on the side having the low refractive index layer. (2) The haze of the sample is measured in accordance with JIS K7136:2000. The measured value is considered to be the internal haze of the optical laminate.

[0127] <Size, Shape, etc.> The optical laminate may be in the form of sheets cut to a predetermined size, or in the form of a roll obtained by winding a long sheet into a roll. The size of the sheets is not particularly limited, but the maximum diameter is approximately 2 inches to 500 inches. The "maximum diameter" refers to the maximum length when any two points on the optical laminate are connected. When the optical laminate is rectangular, the diagonal line of the rectangle is the maximum diameter. When the optical laminate is circular, the diameter of the circle is the maximum diameter. The width and length of the roll are not particularly limited, but generally, the width is approximately 500 mm to 3000 mm and the length is approximately 500 m to 5000 m. The optical laminate in roll form can be cut into sheets to fit the size of an image display device or the like. When cutting, it is preferable to exclude the ends of the roll, which have unstable physical properties. The shape of the sheets is also not particularly limited, and may be, for example, a polygonal shape such as a triangle, a rectangle, or a pentagon, a circular shape, or a random, irregular shape. More specifically, when the optical laminate is rectangular, the aspect ratio is not particularly limited as long as it does not cause any problems as a display screen, and examples include width:height ratios of 1:1, 4:3, 16:10, 16:9, and 2:1.

[0128] [Anti-reflective article] The anti-reflective article of the present disclosure includes a member and the optical laminate of the present disclosure disposed on the member, with the surface of the optical laminate on the low refractive index layer side facing away from the member.

[0129] The optical laminate is preferably disposed on the outermost surface of the antireflective article.

[0130] The member and the optical laminate are preferably laminated via an adhesive layer, which is preferably formed on the resin substrate side of the optical laminate or on the member before laminating the member and the optical laminate.

[0131] Examples of the components include instrument panels, clocks, showcases, show windows, and windows. The components may be transparent or opaque, and there are no particular limitations on the color tone. The components are preferably components with curved surfaces or three-dimensional shapes.

[0132] The following methods (1) and (2) can be used to laminate a member and an optical laminate via an adhesive layer: (1) a lamination method using heat and pressure with a roll transfer device or the like; and (2) a TOM molding method.

[0133] The TOM molding of (2) above includes, for example, the following steps (v1) to (v5). TOM molding is described in JP 2021-178410 A, etc. (v1) A step of placing a member previously molded into a product shape in a lower vacuum chamber of a TOM molding machine having an upper vacuum chamber and a lower vacuum chamber. (v2) A step of placing the surface of the optical laminate of the present disclosure facing the resin substrate facing downward between the upper vacuum chamber and the lower vacuum chamber. It is preferable to form an adhesive layer in advance on the surface of the optical laminate facing the resin substrate. (v3) A step of evacuating the upper vacuum chamber and the lower vacuum chamber. (v4) A step of pushing a member up to the upper vacuum chamber while heating the optical laminate, and pressing the member against the heated optical laminate. (v5) A step of pressurizing the upper vacuum chamber while the optical laminate is heated, and adhering a molding sheet to the exposed surface of the member.

[0134] [Panel] The panel 120 of the present disclosure has a display element 110 and an optical film arranged on the light-emitting surface side of the display element 110, and includes the optical laminate 100 of the present disclosure described above as the optical film, and is arranged so that the surface of the optical laminate 100 on the side of the low refractive index layer 40 faces away from the display element 110 (see Figure 2).

[0135] The optical laminate is preferably disposed on the outermost surface of the panel. The optical laminate is preferably laminated to a member such as a surface plate via an adhesive layer. The member preferably has a curved surface or a three-dimensional shape.

[0136] Examples of the display element include a liquid crystal display element, an EL display element such as an organic EL display element or an inorganic EL display element, a plasma display element, and an LED display element such as a micro LED display element. These display elements may have a touch panel function inside the display element. Examples of the liquid crystal display system of the liquid crystal display element include an IPS system, a VA system, a multi-domain system, an OCB system, an STN system, and a TSTN system.

[0137] The panel of the present disclosure may be a panel with a touch panel, in which case the optical laminate may be used as a component constituting the touch panel.

[0138] The size of the panel is not particularly limited, but the maximum diameter is about 2 inches to 500 inches. The maximum diameter means the maximum length when connecting any two points on the surface of the panel.

[0139] [Image Display Device] The image display device of the present disclosure includes the panel of the present disclosure described above.

[0140] The image display device of the present disclosure preferably further includes a drive control unit electrically connected to the panel, and a housing that houses the panel, the drive control unit, etc. When the display element is a liquid crystal display element, the image display device of the present disclosure requires a backlight. The backlight is disposed on the side opposite to the light-emitting surface of the liquid crystal display element.

[0141] The size of the image display device is not particularly limited, but the maximum diameter of the effective display area is approximately 2 inches or more and 500 inches or less. The effective display area of ​​an image display device is the area in which an image can be displayed. For example, if the image display device has a housing that surrounds the display element, the area inside the housing is the effective display area. The maximum diameter of the effective display area refers to the maximum length when any two points within the effective display area are connected. For example, if the effective display area is rectangular, the diagonal of the rectangle is the maximum diameter. If the effective display area is circular, the diameter of the circle is the maximum diameter.

[0142] The present disclosure includes the following (1) to (15). (1) An optical laminate having a hard coat layer and a low refractive index layer on a resin substrate in this order, the optical laminate satisfying the following conditions 1 and 2. <Condition 1> A first sample measuring 20 mm short sides x 100 mm long sides is cut out from the optical laminate. The first sample is set in a tensile tester with a chuck distance of 50 mm. When the first sample is pulled in the long side direction at 130°C and a tensile speed of 50 mm / min, the elongation of the first sample at the upper yield point is 6.5% or more. <Condition 2> The average thickness of the low refractive index layer before stretching the optical laminate is defined as t1. A second sample measuring 20 mm short sides x 100 mm long sides is cut out from the optical laminate. Marked lines are marked at 50 mm intervals on the second sample, and the second sample is preheated at 130°C for 2 minutes. The second sample after preheating is quickly set in a tensile tester. The distance between the chucks of the tensile tester is adjusted to the distance between the benchmark lines after preheating. The second sample is pulled in the long side direction under conditions of 130°C and a pulling speed of 50 mm / min, and pulling is stopped when the distance between the chucks reaches 60 mm. The second sample is removed from the tensile tester and left at 23°C for 120 minutes, and then the thickness of the low refractive index layer of the second sample after stretching is measured. The average thickness of the low refractive index layer after stretching is designated as t2. The ratio of the thickness of the low refractive index layer after stretching to the thickness of the low refractive index layer before stretching, calculated using the following formula, is 80% or more and 99% or less: Ratio (%) of the thickness of the low refractive index layer after stretching to the thickness of the low refractive index layer before stretching = (t2 / t1) × 100 (2) The optical laminate according to (1), which has a high refractive index layer between the hard coat layer and the low refractive index layer. (3) The optical laminate according to (2), further satisfying the following condition 3. <Condition 3> The average thickness of the high refractive index layer before stretching the optical laminate is defined as t3. A third sample having a size of 20 mm short side x 100 mm long side is cut out from the optical laminate. Marked lines are marked on the third sample at intervals of 50 mm, and the third sample is preheated at 130°C for 2 minutes. After preheating, the third sample is quickly set in a tensile tester. The distance between the chucks of the tensile tester is adjusted to the distance between the marked lines after preheating is completed.The third sample is pulled in the long side direction under conditions of 130°C and a pulling speed of 50 mm / min, and pulling is stopped when the distance between chucks reaches 60 mm. The third sample is removed from the tensile tester and left at 23°C for 120 minutes, after which the thickness of the high refractive index layer of the third sample after stretching is measured. The average thickness of the high refractive index layer after stretching is designated as t4. The ratio of the thickness of the high refractive index layer after stretching to the thickness of the high refractive index layer before stretching, calculated using the following formula, is 80% or more and 99% or less: Ratio (%) of the thickness of the high refractive index layer after stretching to the thickness of the high refractive index layer before stretching = (t4 / t3) x 100 (4) The optical laminate according to (3), wherein the absolute value of the difference between the thickness ratio under condition 2 and the thickness ratio under condition 3 is 3% or less. (5) The optical laminate according to any one of (1) to (4), wherein t1 is 80 nm or more and 150 nm or less. (6) The optical laminate according to (3) or (4), wherein t3 is 80 nm or more and 200 nm or less. (7) The optical laminate according to any one of (1) to (6), wherein t5 is 2.5 μm or more and 13.5 μm or less, when the average thickness of the hard coat before stretching the optical laminate is defined as t5. (8) The optical laminate according to any one of (1) to (7), wherein the elongation at the upper yield point under condition 1 is 17.0% or less. (9) The load at the upper yield point measured under condition 1 is 7.0 mN / mm. ２The optical laminate according to any one of (1) to (8), wherein the low refractive index layer contains hollow particles, and the hollow particles have an average particle diameter of 55.0 nm or more and 130.0 nm or less. (11) The optical laminate according to any one of (1) to (10), wherein the internal haze is 0.4% or less. (12) The optical laminate according to any one of (1) to (11), wherein the pencil hardness of the surface of the optical laminate is H or more, measured in accordance with JIS K5600-5-4:1999 under conditions of a load of 500 g and a speed of 1.4 mm / sec. (13) An antireflection article comprising: a member; and the optical laminate according to any one of (1) to (12) placed on the member, wherein the surface of the optical laminate facing the low refractive index layer faces away from the member. (14) A panel having a display element and an optical film arranged on the light-emitting surface side of the display element, the optical film including the optical laminate according to any one of (1) to (12), and the optical laminate being arranged so that the surface on the low-refractive-index layer side faces away from the display element. (15) An image display device including the panel according to (14).

[0143] Next, the present disclosure will be described in more detail with reference to examples, but the present disclosure is not limited to these examples. "Parts" and "%" are based on mass unless otherwise specified.

[0144] 1. Measurement and Evaluation Measurement and evaluation of the optical laminates of the Examples and Comparative Examples were carried out as follows. The atmosphere during each measurement and evaluation was a temperature of 23°C and a relative humidity of 50%, unless otherwise specified. Before starting each measurement and evaluation, the target sample was exposed to the above atmosphere for 30 to 60 minutes, and then measurement and evaluation were carried out. The samples used for each measurement and evaluation can be prepared by cutting the optical laminates of the Examples and Comparative Examples. The cutting locations were selected from random locations after visually confirming that there were no abnormalities such as dust or scratches.

[0145] 1-1. Measurement of elongation and load at upper yield point Following the procedures A1 to A6 in the specification, the elongation at the upper yield point of the optical laminates of the examples and comparative examples was measured (unit: "%)." The measuring device used was a tester manufactured by Orientec Co., Ltd., model number "RTC-1210A," with option "TCLF" added. The tester is a tensile tester capable of controlling temperature. In addition, the stress (MPa) at the upper yield point and the cross-sectional area (mm ２ ) to calculate the load at the upper yield point of the optical laminate of the example and comparative example (unit: mN / mm ２ ").

[0146] 1-2. Thickness Change Rate Before and After Stretching According to the procedures B1 to B7 of the specification, the thickness ratio of the low refractive index layer of the optical laminate of the Examples and Comparative Examples before and after stretching was measured (unit: "%)." According to the procedures C1 to C7 of the specification, the thickness ratio of the high refractive index layer of the optical laminate of the Examples and Comparative Examples before and after stretching was measured (unit: "%)." When measuring the thickness ratio of the high refractive index layer before and after stretching, the third sample was also used as the second sample. Furthermore, the procedures C2 to C5 were also used for the procedures B2 to B5. The heat-resistant tape used in B3 and C3 was industrial tape WS-1 from Nitto America. In the above measurements, the STEM "S-4800" manufactured by Hitachi High-Technologies Corporation was used to measure thicknesses t1 to t4. The imaging conditions were as follows: <Imaging conditions> Mode: TE Acceleration voltage: 30 kV Emission current: 10 uA WD (Working Distance): 8.0 mm Magnification: 100,000x in high magnification mode In the above measurements, the following materials and equipment were used for the black plate, optically transparent adhesive sheet, microtome, and mesh used to prepare a sample with an exposed cross section of the optical laminate: Black plate (Kuraray Co., Ltd., product name: COMOGLAS DFA2CG 502K (black) series, thickness 2 mm) Optically transparent adhesive sheet (Panac Corporation, product name: Panaclean PD-S1) Microtome (Leica Microsystems, product name: Ultramicrotome EM UC7) Mesh (Nissin EM Co., Ltd., product name: Collodion film-attached mesh (Cat No.: 651)) In the above measurements, the microtome cutting conditions were "SPEED: 1.40 mm / s" and "FEED: 70 nm."

[0147] 1-3. Reflectance (Luminous Reflectance Y Value) <Initial Reflectance> The optical laminates of the Examples and Comparative Examples were cut into 5 cm x 5 cm pieces. A sample was prepared by bonding the resin substrate side of the cut optical laminate to a black plate measuring 5 cm x 5 cm (manufactured by Kuraray Co., Ltd., product name: COMOGLAS DFA2CG 502K (black), thickness 2 mm) via an optically transparent adhesive sheet (Panac Corporation, product name: Panaclean PD-S1). When the direction perpendicular to the surface of the low refractive index layer side of the sample was set to 0 degrees, light was incident on the sample from a direction of 5 degrees, and the luminous reflectance Y value of the sample was measured based on the specular reflection of the incident light. The measured value was taken as "initial reflectance." A spectral reflectance meter (manufactured by Shimadzu Corporation, product name: UV-2450) was used as the measuring device. The measuring device measures reflectance in the wavelength range of 380 nm to 780 nm in 0.5 nm intervals, and then converts the measured values ​​into brightness as perceived by the human eye using software built into the measuring device. The software calculates reflectance under the conditions of a D65 light source and a viewing angle of 2 degrees.

[0148] <Reflectance after molding> A concave lens with a circular bottom (made of glass, bottom diameter 50 mm, side height 20 mm, radius of curvature 170 mm) was placed on a platform in the lower vacuum chamber of a TOM molding machine having an upper vacuum chamber and a lower vacuum chamber. Next, the optical laminates of the examples and comparative examples were placed between the upper and lower vacuum chambers with the resin substrate side facing downward (the concave lens side) and fixed with a jig. Next, the upper and lower vacuum chambers were closed and sealed, and each vacuum chamber was evacuated (vacuum pressure: -0.1 MPa (gauge pressure)). Next, while the optical laminate was heated from the low refractive index layer side (heating temperature: 120 ° C.), the platform was operated to push the concave lens up to the upper vacuum chamber, and the concave lens was pressed against the heated optical laminate. Next, while the optical laminate was heated, the upper vacuum chamber was pressurized (compressed air pressure: 0.2 MPa (gauge pressure)), and the optical laminate was molded to follow the shape of the concave lens. Next, the upper and lower vacuum chambers were opened to the atmosphere, and after air-cooling to room temperature, the concave lens and optical laminate were removed. The concave lens was then peeled off from the molded optical laminate. (Note: Conventional TOM molding involves closely adhering two components. In this example, the reflectance of the molded optical laminate needed to be measured without the concave lens, so the concave lens and the optical laminate were not closely adhering to each other in the TOM molding.) Next, the optical laminate molded into the shape of a concave lens was flattened, and then a sample was prepared by bonding the adhesive layer side of a laminate made of an adhesive layer and a black plate to the resin substrate side of the optical laminate. The adhesive layer was an optically transparent adhesive sheet (Panac Corporation, product name: Panaclean PD-S1). The black plate was a black plate manufactured by Kuraray Co., Ltd. (product name: COMOGLASS DFA2CG 502K (black) series, thickness: 2 mm). When the direction perpendicular to the surface of the low refractive index layer side of the sample was set to 0 degrees, light was incident on the sample from a direction of 5 degrees, and the luminous reflectance Y value of the sample was measured based on the specular reflection of the incident light. The measured value was taken as the "reflectance after molding." The same measuring device as for the initial reflectance was used. The reflectance after molding could not be measured for Comparative Example 2 because it was not suitable for non-flat shapes.

[0149] The difference between the initial reflectance and the reflectance after molding (reflectance after molding - initial reflectance) is shown in Tables 1 and 2. A difference of 0.04% or less is considered acceptable. The initial reflectance means the reflectance before molding. Furthermore, Tables 1 and 2 show ((reflectance after molding - initial reflectance) / initial reflectance) x 100 (unit: "%)). A ratio of 35.0% or less is considered acceptable.

[0150] When the initial reflectance (%) of the sample is defined as Y21 and the reflectance (%) of the sample after molding is defined as Y22, it is preferable to satisfy the following condition A or condition B, and it is more preferable to satisfy both conditions A and B. The difference under condition A is preferably 0.02% or less, and more preferably 0.01% or less. The ratio under condition B is preferably 10.0% or less, more preferably 5.0% or less, and even more preferably 1.0% or less. The reflectance in the above measurement means the luminous reflectance Y value measured based on the specularly reflected light of incident light, when the direction perpendicular to the surface of the low refractive index layer side of the sample is defined as 0 degrees, by irradiating light onto the sample from a direction of 5 degrees. <Condition A> Y22 - Y21 ≦ 0.04% <Condition B> ((Y22 - Y21) / Y21) × 100 ≦ 35.0%

[0151] 1-4. Suitability for Non-flat Shapes The applicability of the optical laminates of the Examples and Comparative Examples to non-flat shapes was evaluated according to the following criteria. The evaluation was carried out visually by healthy people in their 30s with a visual acuity of 1.0 or better. A: No cracks were observed in the low refractive index layer. B: Cracks were observed in the low refractive index layer, but the cracks were observed in only one direction. C: Cracks were observed in two or more directions in the low refractive index layer.

[0152] 1-5. Pencil Hardness Samples were prepared by cutting the optical laminates of the Examples and Comparative Examples to a size of 5 cm x 10 cm. In accordance with JIS K5600-5-4:1999, the pencil hardness of the surface of the sample facing the low refractive index layer was measured under conditions of a load of 500 g and a speed of 1.4 mm / sec. A Toyo Seiki Seisakusho pencil hardness tester (product number: NP-type pencil scratch coating hardness tester) was used for the measurement. Both ends of the cut sample were attached to the base of the pencil hardness tester using mending tape (3M, product number "810-3-18"). Five pencil hardness tests were performed, and the hardness at which no appearance abnormalities such as scratches were observed four or more times was recorded as the pencil hardness value of each sample. For example, if five tests were performed using a 2H pencil and no appearance abnormalities occurred four times, the pencil hardness of that sample was 2H. Appearance abnormalities were checked for scratches and dents, excluding discoloration. A pencil hardness of H or higher is considered to be acceptable.

[0153] 1-6. Total Light Transmittance (Tt), Haze, Internal Haze The optical laminates of the Examples and Comparative Examples were cut into 10 cm x 10 cm pieces to prepare measurement samples. Using a haze meter (HM-150, manufactured by Murakami Color Research Laboratory), the total light transmittance of each sample according to JIS K7361-1:1997 and the haze according to JIS K7136:2000 were measured under the following conditions. Next, an 80 μm thick TAC film (manufactured by Fujifilm Corporation, TD80UL) was attached to the surface of the low refractive index layer side of the optical laminates of the Examples and Comparative Examples via a transparent adhesive (manufactured by Panac Corporation, PD-S1, thickness 25 μm) to flatten the uneven surface, thereby preparing a sample in which the influence of haze due to the surface shape was eliminated. The haze of the sample according to JIS K7136:2000 was measured, and the obtained value was taken as the internal haze. <Conditions> To stabilize the light source, the power switch of the device was turned on in advance, and then calibration was performed after 15 minutes had passed without placing anything in the entrance opening where the measurement sample was placed. After that, the measurement sample was placed in the entrance opening, and the total light transmittance and haze were measured. The light incident surface during measurement was the substrate side.

[0154] 2. Preparation of Coating Solution for Hard Coat Layer <Coating Solution for Hard Coat Layer of Example 1> The following materials were mixed and stirred to obtain the coating solution for hard coat layer of Example 1. - Urethane acrylate oligomer 49 parts by mass (average number of functional groups: 3, weight average molecular weight: 700 to 1200) - Pentaerythritol triacrylate 18 parts by mass (Nippon Kayaku Co., Ltd., product name: PET-30) - Monofunctional acrylic monomer 33 parts by mass (Kyoeisha Chemical Co., Ltd., product name: Light Acrylate PO-A) - Photopolymerization initiator 5 parts by mass (IGM Resins, product name: Omnirad184) - Leveling agent 0.5 parts by mass (DIC, product name: F-568) - Dilution solvent (a mixed solvent of methyl ethyl ketone and methyl isobutyl ketone in a mass ratio of 1:1, prepared so that the solid content was 30% by mass).

[0155] <Coating liquid for hard coat layer of Examples 2 to 9 and Comparative Examples 1 to 3> The coating liquid for hard coat layer of Examples 2 to 9 and Comparative Examples 1 to 3 was obtained in the same manner as in Example 1, except that the formulation of the binder resin composition was changed to the formulations in Tables 1 and 2.

[0156] 3. Preparation of Coating Liquid for High Refractive Index Layer Coating Liquid for High Refractive Index Layer of Examples 1 to 9 and Comparative Examples 2 to 3 The following materials were mixed and stirred to obtain coating liquids for high refractive index layers of Examples 1 to 9 and Comparative Examples 2 to 3. Urethane acrylate 100 parts by mass (Kyoeisha Chemical Co., Ltd., product name "UA-306H") Zirconium oxide particles 130 parts by mass (average particle size: 20 nm) Photopolymerization initiator 5 parts by mass (IGM Resins, product name: Omnirad184) Leveling agent 0.4 parts by mass (BYK, product name: BYK-331) Methyl isobutyl ketone 7,000 parts by mass

[0157] <Coating liquid for high refractive index layer of Comparative Example 1> A coating liquid for high refractive index layer of Comparative Example 1 was obtained in the same manner as in Example 1, except that the zirconium oxide particles having an average particle diameter of 20 nm were changed to zirconium oxide particles having an average particle diameter of 40 nm.

[0158] 4. Preparation of Coating Liquid for Low Refractive Index Layer <Coating Liquid for Low Refractive Index Layer of Example 1> The following materials were mixed and stirred to obtain a coating liquid for low refractive index layer of Example 1. Hexafunctional acrylate monomer 100 parts by mass (solid content equivalent) (DPHA) Hollow silica particles 130 parts by mass (average particle diameter 75 nm, hollow silica particles surface-treated with a silane coupling agent having a methacryloyl group) Solid silica particles 10 parts by mass (average particle diameter 12 nm) Leveling agent 0.1 parts by mass (Dainichiseika Color & Chemicals Mfg. Co., Ltd., product name: Seikabeam 1028 (MB)) Photopolymerization initiator 5 parts by mass (IGM Resins, product name: Omnirad 127) Methyl ethyl ketone 1700 parts by mass Methyl isobutyl ketone 4300 parts by mass Propylene glycol monomethyl ether acetate 2500 parts by mass

[0159] <Coating Liquids for Low Refractive Index Layers in Examples 2 to 10 and Comparative Examples 1 to 3> Coating liquids for low refractive index layers in Examples 2 to 10 and Comparative Examples 1 to 3 were obtained in the same manner as in Example 1, except that the average particle diameter of the hollow silica particles was set to the average particle diameters shown in Tables 1 and 2 (the average particle diameter of the hollow silica in Example 4 was 60 nm, and the average particle diameter of the hollow silica in Example 9 and Comparative Examples 1 and 3 was 100 nm). Note that the coating liquids for low refractive index layers in Examples 8 and 10 contained 100 parts by mass of hollow silica particles having an average particle diameter of 75 nm and 30 parts by mass of hollow silica particles having an average particle diameter of 100 nm.

[0160] 5. Preparation of Optical Laminate [Example 1] The hard coat layer coating solution of Example 1 was applied onto a 40 μm thick polymethyl methacrylate substrate (Tg=125° C.), and then dried at 70° C. for 1 minute to volatilize the solvent. Then, in a nitrogen atmosphere, the hard coat layer was dried under an integrated light intensity of 100 mJ / cm 2 . ２ The hard coat layer was then coated with the coating solution for the high refractive index layer of Example 1, and dried at 70°C for 1 minute to volatilize the solvent. ２A high refractive index layer having a dry thickness of 155 nm was formed by irradiating the coating solution for the low refractive index layer of Example 1 onto the high refractive index layer, and then drying at 40°C for 60 seconds to volatilize the solvent. ２ By irradiating the film with ultraviolet light at 1000 W at this temperature, a low refractive index layer having a dry thickness of 106 nm was formed, and an optical laminate of Example 1 was obtained.

[0161] [Examples 2 to 10], [Comparative Examples 1 and 3] The coating liquid for the hard coat layer, the coating liquid for the high refractive index layer, and the coating liquid for the low refractive index layer were changed to the coating liquids for Examples 2 to 10 and Comparative Examples 1 and 3, respectively, and further, the thicknesses of the hard coat layer, the high refractive index layer, and the low refractive index layer were changed to the values ​​in Tables 1 and 2. Except for this, the optical laminates of Examples 2 to 10 and Comparative Examples 1 and 3 were obtained in the same manner as in Example 1.

[0162] Comparative Example 2 An optical laminate of Comparative Example 2 was obtained in the same manner as in Example 1, except that the resin substrate was changed to a triacetyl cellulose film having a thickness of 80 μm (trade name "Fujitack" manufactured by Fujifilm Corporation), the coating liquid for the hard coat layer, the coating liquid for the high refractive index layer, and the coating liquid for the low refractive index layer were changed to the coating liquids for Comparative Example 2, and further the thicknesses of the hard coat layer, the high refractive index layer, and the low refractive index layer were changed to the values ​​in Table 2.

[0163]

[0164]

[0165] In Tables 1 and 2, "PETA" represents pentaerythritol triacrylate, "PMMA" represents polymethyl methacrylate film, and "TAC" represents triacetyl cellulose film. In Tables 1 and 2, "R1" represents the mass proportion of pentaerythritol triacrylate relative to the total amount of the resin composition, "R2" represents the mass proportion of urethane acrylate oligomer relative to the total amount of the resin composition, and "R3" represents the mass proportion of monofunctional acrylic monomer relative to the total amount of the resin composition. The units of R1 to R3 are all "% by mass."

[0166] From the results in Tables 1 and 2, it can be confirmed that the optical laminates of the examples can provide good antireflection properties even when applied to members with non-flat shapes.

[0167] 10: Resin substrate 20: Hard coat layer 30: High refractive index layer 40: Low refractive index layer 100: Optical laminate 110: Display element 120: Panel

Claims

1. An optical laminate having a hard coat layer and a low refractive index layer in this order on a resin substrate, which satisfies the following Conditions 1 and 2. <Condition 1> A first sample having a size of 20 mm in short side × 100 mm in long side is cut out from the optical laminate. Set the first sample on a tensile testing machine with a chuck distance of 50 mm. When the first sample is pulled in the long side direction under the conditions of 130°C and a tensile speed of 50 mm / min, the elongation at the upper and lower yield points of the first sample is 6.5% or more. <Condition 2> Let the average thickness of the low refractive index layer before stretching the optical laminate be t1. Cut out a second sample with a size of 20 mm in the short side × 100 mm in the long side from the optical laminate. After marking gauge lines with an interval of 50 mm on the second sample, preheat it at 130°C for 2 minutes. Quickly set the second sample after preheating on the tensile testing machine. The chuck distance of the tensile testing machine is adjusted to the distance between the gauge lines after preheating is completed. Pull the second sample in the long side direction under the conditions of 130°C and a tensile speed of 50 mm / min, and stop pulling when the chuck distance reaches 60 mm. Remove the second sample from the tensile testing machine, leave it at 23°C for 120 minutes, and then measure the thickness of the low refractive index layer after stretching of the second sample. Let the average thickness of the low refractive index layer after stretching be t2. The ratio of the thickness of the low refractive index layer after stretching to the thickness of the low refractive index layer before stretching calculated from the following formula is 80% or more and 99% or less. Ratio of the thickness of the low refractive index layer after stretching to the thickness of the low refractive index layer before stretching (%) = (t2 / t1) × 100 2. The optical laminate according to claim 1, having a high refractive index layer between the hard coat layer and the low refractive index layer.

3. The optical laminate according to claim 2, further satisfying the following condition 3. <Condition 3> Let the average of the thicknesses of the high refractive index layers before stretching the optical laminate be t3. Cut out a third sample with a size of 20 mm in the short side × 100 mm in the long side from the optical laminate. After marking gauge lines with an interval of 50 mm on the third sample, preheat it at 130°C for 2 minutes. Quickly set the third sample after preheating on the tensile testing machine. The chuck distance of the tensile testing machine is adjusted to the distance between the gauge lines after preheating is completed. Pull the third sample in the long side direction under the conditions of 130°C and a tensile speed of 50 mm / min, and stop pulling when the chuck distance reaches 60 mm. Remove the third sample from the tensile testing machine, leave it at 23°C for 120 minutes, and then measure the thickness of the high refractive index layer after stretching of the third sample. Let the average thickness of the high refractive index layer after stretching be t4. The ratio of the thickness of the high refractive index layer after stretching to the thickness of the high refractive index layer before stretching, calculated from the following formula, is 80% or more and 99% or less. Ratio (%) of the thickness of the high refractive index layer after stretching to the thickness of the high refractive index layer before stretching = (t4 / t3) × 100 4. The optical laminate according to claim 3, wherein the absolute value of the difference between the thickness ratio of the condition 2 and the thickness ratio of the condition 3 is 3% or less.

5. The optical laminate according to claim 1, wherein t1 is 80 nm or more and 150 nm or less.

6. The optical laminate according to claim 3, wherein t3 is 80 nm or more and 200 nm or less.

7. The optical laminate according to claim 1, wherein when the average thickness of the hard coat before stretching the optical laminate is defined as t5, t5 is 2.5 μm or more and 13.5 μm or less.

8. The optical laminate according to claim 1, wherein the elongation at the upper yield point of the condition 1 is 17.0% or less.

9. The load at the upper yield point measured under the condition 1 is 7.0 mN / mm ２ or less. The optical laminate according to claim 1.

10. The optical laminate according to claim 1, wherein the low refractive index layer contains hollow particles, and the average particle diameter of the hollow particles is 55.0 nm or more and 130.0 nm or less.

11. The optical laminate according to claim 1, wherein the internal haze is 0.4% or less.

12. The optical laminate according to claim 1, wherein the pencil hardness of the surface of the optical laminate, measured in accordance with JIS K5600-5-4:1999 under the conditions of a load of 500 g and a speed of 1.4 mm / second, is H or more.

13. An antireflective article having a member and the optical laminate according to any one of claims 1 to 12 disposed on the member, wherein the surface of the optical laminate on the low refractive index layer side faces away from the member.

14. A panel having a display element and an optical film disposed on the light-emitting surface side of the display element, wherein the optical film includes the optical laminate according to any one of claims 1 to 12, and the surface of the optical laminate on the low refractive index layer side faces away from the display element.

15. An image display device including the panel according to claim 14.

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