Laminated film and image display device

Abstract

To provide a laminated film excellent in scratch resistance.SOLUTION: A resin layer that is formed on the base material layer and has a concavo-convex surface on a side opposite to the base material layer, in which an average area occupancy of convex portions of the concavo-convex surface is 6% or more, in the laminated film, B1 / A1 is 0.80 or more, B2 / A2 is 0.60 or more, B3 / A3 is 0.60 or more, and B4 / A4 is 0.60 or more (in the laminated film, A1,,, and are Ra, Rz, Rc, and Rzjis of the uneven surface before the abrasion resistance test, respectively, and non-Ra, Rz, Rc, and Rzjis of the uneven surface after the abrasion resistance test are non-Ra, Rz, Rc, and Rzjis of the uneven surface after the abrasion resistance test, respectively). B3 A2 B4 B2 A3 B1 A4.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present disclosure relates to a laminated film and an image display device. [Background technology]

[0002] Films having a textured surface are widely used as water-repellent films, anti-glare films, and films for improving the writing feel of touch panels.

[0003] For example, Patent Document 1 describes a film for improving writing feel, which has large and small protrusions on its surface at a specific density, thereby providing a writing feel similar to that of writing on paper with a pencil or pen. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 2018-097670 Summary of the Invention [Problem to be solved by the invention]

[0005] However, the scratch resistance of conventional products is not sufficient, and the writing feel improvement film described in Patent Document 1 can become scratched on the surface when repeatedly used with a touch pen, and the surface irregularities can wear away due to wear, gradually making it impossible to achieve the desired writing feel.

[0006] An object of the present disclosure is to provide a laminated film having excellent scratch resistance. [Means for solving the problem]

[0007] In order to solve the above problems, the present inventors have conducted extensive research and have found that the scratch resistance of a laminate film can be improved by adjusting the area occupancy of the convex portions on the surface of the laminate film.

[0008] [1] a base layer; and a resin layer formed on the base layer, the resin layer having an uneven surface on the opposite side to the base layer, the uneven surface having an uneven shape; When the surface shape of the uneven surface is measured with an optical interference type surface shape measuring device over a measurement area of ​​189.46 μm × 252.5 μm, the average area occupancy of convex portions having a height of 0.3 μm or more is 6% or more, A laminated film that satisfies one or more of the following (a) to (d) when an abrasion resistance test is conducted on the uneven surface using an abrasive wheel under the conditions of a load of 750 g, a sliding distance of 5 cm, a sliding speed of 40 reciprocations per minute, and a number of reciprocations of 100: (a) B1 / A1 ≧ 0.80 (b) B2 / A2 ≧ 0.60 (c) B3 / A3 ≧ 0.60 (d) B4 / A4 ≧ 0.60 (In formulas (a) to (d), A1 is the two-dimensional average roughness Ra of the roughness curve element of the uneven surface before the abrasion resistance test; B1 is the two-dimensional average roughness Ra of the roughness curve element of the uneven surface after the abrasion resistance test; A2 is the maximum height Rz of the roughness curve element of the uneven surface before the abrasion resistance test; B2 is the maximum height Rz of the roughness curve element of the uneven surface after the abrasion resistance test; A3 is the average roughness height Rc of the roughness curve element of the rough surface before the abrasion resistance test; B3 is the average unevenness height Rc of the roughness curve elements of the uneven surface after the abrasion resistance test; A4 is the 10-point average roughness Rzjis of the roughness curve element of the uneven surface before the abrasion resistance test; B4 is the 10-point average roughness Rzjis of the roughness curve elements of the uneven surface after the abrasion resistance test. [2] The laminated film according to [1], wherein the number of scratches having a width of 0.1 mm or more and a length of 1.0 mm or more generated by the abrasion resistance test is 5 or less. [3] The laminated film according to [1] or [2], which has a pencil hardness of H or more as measured in accordance with JIS K 5600-5-4:1999. [4] The laminated film according to any one of [1] to [3], which has a total light transmittance of 85% or more. [5] The laminated film according to any one of [1] to [4], which has a haze of 5% or more and 35% or less. [6] The laminated film according to any one of [1] to [5], wherein the resin layer contains fine particles. [7] The laminated film according to [6], wherein the average particle size of the fine particles is 1 μm or more and 16 μm or less. [8] The laminated film according to [6] or [7], wherein the difference between the refractive index of the base resin contained in the resin layer and the refractive index of the fine particles is 0.00 or more and 0.10 or less. [9] The laminated film according to any one of [1] to [8], wherein the resin layer contains nanoparticles having an average particle size of 200 nm or less.

[10] The laminated film according to any one of [1] to [9], wherein the base layer is a polyester film.

[11] The laminate film according to any one of [1] to

[10] , which is a film for improving writing feel for a touch panel.

[12] A laminate sheet comprising the laminate film according to any one of [1] to

[11] and a protective film disposed on at least one side of the laminate film.

[13] A laminate sheet comprising the laminate film according to any one of [1] to

[11] and an adhesive layer disposed on at least one surface of the laminate film.

[14] An image display device comprising the laminate film according to any one of [1] to

[11] . [Effects of the Invention]

[0009] According to the present disclosure, an effect can be achieved in which a laminated film having excellent scratch resistance can be provided. The problems and advantages of the present disclosure are not limited to those specifically described above, but also include those that will become apparent to those skilled in the art from the entire specification. [Brief explanation of the drawings]

[0010] [Figure 1] 1 is a cross-sectional view schematically illustrating an example of a laminated film according to a first embodiment of the present disclosure. [Figure 2] 1 is a cross-sectional view schematically illustrating an example of a laminated film according to a first embodiment of the present disclosure. [Figure 3] FIG. 4 is a cross-sectional view schematically illustrating an example of a laminate sheet according to a second embodiment of the present disclosure. [Figure 4] FIG. 4 is a cross-sectional view schematically illustrating an example of a laminate sheet according to a third embodiment of the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0011] The present disclosure will be described below with reference to specific embodiments, but the configurations and combinations thereof in each embodiment are merely examples, and additions, omissions, substitutions, and other modifications of the configurations are possible as appropriate within the scope of the gist of the present disclosure. The present disclosure is not limited to the embodiments. Additionally, each feature disclosed herein can be combined with any other feature disclosed herein.

[0012] In the present disclosure, the range "X to Y" means "X or more and Y or less." Furthermore, when a numerical range expressed as "X to Y" or "X or more and Y or less" is stated in stages (for example, in order of preference), the upper and lower limits of each numerical range can be combined in any way.

[0013] In the present disclosure, a description such as "one or more selected from the group consisting of X, Y, and Z" means any of X, Y, Z, a combination of X and Y, a combination of X and Z, a combination of Y and Z, or a combination of X, Y, and Z.

[0014] In the present disclosure, a description such as "X such as x1, x2, and x3" lists x1, x2, and x3 as examples of X, and does not mean that X is limited to x1, x2, x3, and the like.

[0015] 1.Laminated film A laminated film according to one embodiment of the present disclosure includes a substrate layer and a resin layer formed on the substrate layer, the resin layer having a textured surface on the side opposite the substrate layer. When the surface profile of the textured surface is measured using an optical interferometer over a measurement area of ​​189.46 μm × 252.5 μm, the average area occupancy of convex portions of 0.3 μm or more in height is 6% or more. Furthermore, when an abrasion resistance test is performed on the textured surface using an abrasive wheel under conditions of a load of 750 g, a sliding distance of 5 cm, a sliding speed of 40 reciprocations per minute, and 100 reciprocations, the laminated film satisfies one or more of the following (a) to (d), and preferably satisfies all of (a) to (d): (a) B1 / A1 ≧ 0.80 (b) B2 / A2 ≧ 0.60 (c) B3 / A3 ≧ 0.60 (d) B4 / A4 ≧ 0.60 (In formulas (a) to (d), A1 is the two-dimensional average roughness Ra of the roughness curve element of the uneven surface before the wear resistance test; B1 is the two-dimensional average roughness Ra of the roughness curve element of the uneven surface after the wear resistance test; A2 is the maximum height Rz of the roughness curve element of the uneven surface before the wear resistance test; B2 is the maximum height Rz of the roughness curve element of the uneven surface after the wear resistance test; A3 is the average unevenness height Rc of the roughness curve element of the uneven surface before the wear resistance test; B3 is the average unevenness height Rc of the roughness curve element of the uneven surface after the wear resistance test; A4 is the 10-point average roughness Rzjis of the roughness curve element of the uneven surface before the wear resistance test; B4 is the 10-point average roughness Rzjis of the roughness curve element of the uneven surface after the abrasion resistance test.

[0016] Fig. 1 shows a cross-sectional view of one embodiment of the laminate film according to the present invention. In Fig. 1, the laminate film 10 includes a base layer 11 and a resin layer 13 having an uneven surface 13a on the side opposite to the base layer 11. The laminate film 10 may also include other layers (not shown) as described below. .

[0017] In this disclosure, "formed on the X layer" not only means being formed directly above the X layer (i.e., adjacent to the X layer), but also includes being formed on the X layer via any layer.

[0018] The laminated film of this embodiment has good scratch resistance by setting the average area occupancy rate of convex portions having a height of 0.3 μm or more to a certain value or more, and when this laminated film is used as a writing feel improving film for a touch panel, it can achieve a good writing feel similar to that when writing on paper with a writing instrument.

[0019] In this disclosure, "touch panel" means a device that combines a display device such as an LCD panel with a position input device such as a touchpad, and that allows input or device operation by physical contact with a finger or a touch pen.

[0020] Furthermore, the laminate film according to this embodiment satisfies one or more of the above (a) to (d). This means that the convex portions on the surface of the resin layer of the laminate film are resistant to wear, and the shape of the convex portions is maintained even after an abrasion resistance test. Therefore, when the laminate film according to this embodiment is used as a film for improving the writing feel on a touch panel, deterioration of the writing feel caused by repeated input with a touch pen can be reduced.

[0021] The laminate film according to this embodiment can be used for the usual applications of films having an uneven surface, such as a water-repellent film, an anti-glare film, a protective film, and a film for improving the writing feel for touch panels, etc. Among these, the laminate film according to this embodiment can exhibit the effects described above, and therefore can be particularly suitably used as a film for improving the writing feel for touch panels.

[0022] 1-1. Physical properties of laminated film 1-1-1. Average area occupancy of convex parts with a height of 0.3 μm or more The uneven surface of the resin layer is formed with a plurality of convex portions, forming an uneven shape. In the present disclosure, the "average area occupancy of convex portions having a height of 0.3 μm or more (hereinafter, sometimes simply referred to as "average area occupancy of convex portions")" refers to the average area ratio of the convex portions having a height of 0.3 μm or more on the uneven surface. The greater the average area occupancy of the convex portions on the uneven surface of the resin layer, the more likely it is that when friction is applied to the laminate film due to contact with a pointed object, such as a touch pen, the object will ride up onto the convex portions, thereby reducing the chance of the object coming into contact with the base surface of the film, which is primarily composed of the concave portions of the film. As a result, the scratch resistance of the laminate film can be improved.

[0023] The average area occupancy of the convex portions on the uneven surface is usually 6% or more, preferably 7% or more, more preferably 9% or more, and even more preferably 10% or more. There are no particular limitations on the upper limit of the average area occupancy of the convex portions on the uneven surface, but it is preferably 50% or less, more preferably 30% or less, even more preferably 20% or less, and even more preferably 15% or less. That is, preferred ranges for the average area occupancy of the convex portions on the uneven surface include, for example, 6% to 50%, 7% to 30%, 9% to 20%, and 10% to 15%.

[0024] By setting the average area occupancy of the convex portions on the uneven surface to the above lower limit or more, the scratch resistance of the laminate film can be improved. By setting the average area occupancy of the convex portions on the uneven surface to the above upper limit or less, when the laminate film is used as a writing feel improving film for a touch panel, it becomes easier to achieve a good writing feel like writing on paper with a writing implement.

[0025] The average area occupancy of the convex portions on the uneven surface can be adjusted to the above range by a method depending on the method for forming the convex portions. For example, when the convex portions are formed by embossing, the average area occupancy of the convex portions can be adjusted to the above range by selecting a stamper depending on the desired area occupancy of the convex portions; when the convex portions are formed by etching, the average area occupancy of the convex portions can be adjusted to the above range by selecting an etching mask having a pattern depending on the desired area occupancy of the convex portions; when the convex portions are formed by incorporating fine particles described later into the resin layer, the average particle size and content of the fine particles can be set to the below-mentioned ranges.

[0026] The average area occupancy of the convex portions can be determined by measuring the surface shape of the concave-convex surface with an optical interference type surface shape measuring device and processing the image. The specific method is as follows.

[0027] (1) Cut out a sample measuring 6 cm x 6 cm from the laminated film. (2) Using an optical interference surface profiler (e.g., Hitachi High-Tech's "VertScan2.0 R3300G Lite"), measure the uneven surface of the resin layer of the sample in 10 fields of view with a measurement area of ​​189.46 μm × 252.5 μm. The objective lens magnification is 50x. The sample is set on the stage so that the measurement Y axis is in the longitudinal direction of the laminated film (the direction in which the film is wound). The measurement is performed by sandwiching the sample between two metal frames containing rubber packing, and removing any slack or curl from the sample. (3) Using surface analysis software (for example, "VS-Viewer" manufactured by Ryoka Systems Co., Ltd.), process and analyze the image obtained in (2) under the following conditions to detect convexities with a height of 0.3 μm or more and determine their occupied area. This is divided by the measured area to calculate the area occupied by convexities with a height of 0.3 μm or more. Image processing conditions Interpolation process: Full interpolation (only data with 90% or more valid pixels before interpolation is valid) Surface correction: 4th order correction ·Analysis conditions Analysis type: sudden analysis Height threshold: 0.3 μm Reference height: Zero plane (average plane) Re-binarization: No Particle shaping: No (4) For all 10 fields of view, calculate the area occupancy rate of convex portions having a height of 0.3 μm or more using (3), and take the average value as the average area occupancy rate of convex portions having a height of 0.3 μm or more.

[0028] However, if the longitudinal direction of the laminated film is unknown in (2), instead of measuring 10 visual fields, perform the following operation X three times to measure 9 visual fields. Then, perform (3) and (4) on the measurement results of these 9 visual fields to determine the average area occupancy of protrusions with a height of 0.3 μm or more. Operation X: Set the sample so that the measurement Y axis is in one direction of the sample and measure the uneven surface, then rotate the sample 120 degrees and measure the uneven surface, then rotate the sample again 120 degrees in the same direction and measure the uneven surface. Here, once operation X is performed, the sample is set so that the measurement Y axis is in one arbitrary direction of the sample, and the next operation X is then performed immediately. In other words, after the sample is set so that the measurement Y axis is in one arbitrary direction of the sample and the uneven surface is measured, the sample is rotated 120 degrees and the uneven surface is measured eight times, measuring a total of nine fields of view.

[0029] In addition, the "zero plane (average plane)" for setting the reference height in the analysis conditions is as follows: The plane of the "average height (Ave)" calculated by the formula is used.

[0030]

number

[0031] During the ceremony, lx is the range length in the X-axis direction in each measurement image that has undergone image processing. ly is the range length in the Y-axis direction in each measurement image that has undergone image processing. h(x, y) is the height at each image point (x, y) in the measurement image that has been subjected to image processing.

[0032] 1-1-2. Surface roughness of the resin layer The surface roughness of the uneven surface of the resin layer of the laminate film according to the present disclosure can be evaluated by one or more selected from the group consisting of the two-dimensional average roughness Ra of the roughness curve element (hereinafter sometimes simply referred to as the "two-dimensional average roughness Ra"), the maximum height Rz of the roughness curve element (hereinafter sometimes simply referred to as the "maximum height Rz"), the average unevenness height Rc of the roughness curve element (hereinafter sometimes simply referred to as the "average unevenness height Rc"), and the 10-point average roughness Rzjis of the roughness curve element (hereinafter sometimes simply referred to as the "10-point average roughness Rzjis").

[0033] The two-dimensional average roughness Ra of the uneven surface is preferably 0.55 μm or more, more preferably 0.60 μm or more, even more preferably 0.70 μm or more, still more preferably 0.75 μm or more, and is preferably 1.50 μm or less, more preferably 1.30 μm or less, even more preferably 1.20 μm or less, and still more preferably 1.00 μm or less. That is, preferred ranges for the two-dimensional average roughness Ra of the uneven surface include, for example, 0.55 μm or more and 1.50 μm or less, 0.60 μm or more and 1.30 μm or less, 0.70 μm or more and 1.20 μm or less, and 0.75 μm or more and 1.00 μm or less.

[0034] The maximum height Rz of the uneven surface is preferably 4.20 μm or more, more preferably 4.45 μm or more, even more preferably 4.50 μm or more, still more preferably 5.00 μm or more, and is preferably 7.50 μm or less, more preferably 6.80 μm or less, even more preferably 6.20 μm or less, still more preferably 5.50 μm or less. That is, preferred ranges for the maximum height Rz of the uneven surface include, for example, 4.20 μm or more and 7.50 μm or less, 4.45 μm or more and 6.80 μm or less, 4.50 μm or more and 6.20 μm or less, and 5.00 μm or more and 5.50 μm or less.

[0035] The average irregularity height Rc of the irregular surface is preferably 3.00 μm or more, more preferably 3.20 μm or more, even more preferably 3.50 μm or more, and is preferably 5.20 μm or less, more preferably 4.80 μm or less, even more preferably 4.20 μm or less, and even more preferably 4.00 μm or less. That is, preferred ranges for the average irregularity height Rc of the irregular surface include, for example, 3.00 μm or more and 5.20 μm or less, 3.20 μm or more and 4.80 μm or less, 3.50 μm or more and 4.20 μm or less, and 3.50 μm or more and 4.00 μm or less.

[0036] The ten-point average roughness Rzjis of the uneven surface is preferably 3.00 μm or more, more preferably 3.20 μm or more, even more preferably 3.35 μm or more, still more preferably 3.70 μm or more, and is preferably 5.30 μm or less, more preferably 4.80 μm or less, even more preferably 4.50 μm or less, still more preferably 4.00 μm or less. That is, the ten-point average roughness Rzjis of the uneven surface is preferably within a range of, for example, 3.0 Examples of the range include 0 μm or more and 5.30 μm or less, 3.20 μm or more and 4.80 μm or less, 3.35 μm or more and 4.50 μm or less, and 3.70 μm or more and 4.00 μm or less.

[0037] It is preferable that one or more of the two-dimensional average roughness Ra, maximum height Rz, average unevenness height Rc, and 10-point average roughness Rzjis of the uneven surface are within the above range, and it is more preferable that all of them are within the above range, since when the laminated film is used as a writing feel improving film for a touch panel, it becomes easier to achieve a good writing feel similar to that when writing on paper with a writing instrument.

[0038] The two-dimensional average roughness Ra, maximum height Rz, average height Rc of the irregularities, and ten-point average roughness Rzjis of the irregular surface can be adjusted to fall within the above ranges by a method suited to the method of forming the protrusions. For example, when the protrusions are formed by embossing, a stamper suited to the desired surface roughness can be selected; when the protrusions are formed by etching, an etching mask having a pattern suited to the desired surface roughness can be selected; when the protrusions are formed by incorporating fine particles (described later) into a resin layer, the average particle size and content of the fine particles can be set within the ranges described later.

[0039] The two-dimensional average roughness Ra, maximum height Rz, average roughness height Rc, and ten-point average roughness Rzjis of an uneven surface are measured in accordance with JIS B 0601:2013 (Geometrical Product Specifications (GPS) - Surface Texture: Profile Curve Method - Terms, Definitions, and Surface Texture Parameters, revised March 21, 2013) using a surface roughness measuring instrument (for example, "SURFCOM 1400G-12" manufactured by Tokyo Seimitsu Co., Ltd.) under the following conditions: Surface roughness measurement conditions Measurement length: 10 mm Measurement speed: 0.3mm / sec Cutoff wavelength (λc): 0.8 mm Probe tip radius: 2 μm Cone angle: 90°

[0040] 1-1-3.Abrasion resistance The laminated film according to this embodiment satisfies one or more of the above (a) to (d) when subjected to an abrasion resistance test.

[0041] (a) relates to the ratio (B1 / A1) of the two-dimensional average roughness Ra of the uneven surface after the abrasion resistance test to the two-dimensional average roughness Ra of the uneven surface before the abrasion resistance test, and is usually 0.80 or more, preferably 0.90 or more, more preferably 0.95 or more, and even more preferably 0.99 or more. The upper limit of B1 / A1 is not particularly limited, but is preferably 1.00 or less. That is, preferred ranges of B1 / A1 include, for example, 0.80 to 1.00, 0.90 to 1.00, 0.95 to 1.00, and 0.99 to 1.00.

[0042] (b) relates to the ratio (B2 / A2) of the maximum height Rz of the uneven surface after the abrasion resistance test to the maximum height Rz of the uneven surface before the abrasion resistance test, and is usually 0.60 or more, preferably 0.70 or more, more preferably 0.75 or more, and even more preferably 0.77 or more. The upper limit of B2 / A2 is not particularly limited, but is preferably 1.00 or less, 0.90 or less, or 0.80 or less. That is, preferred ranges of B2 / A2 include, for example, 0.60 or more and 1.00 or less, 0.70 or more and 1.00 or less, 0.75 or more and 0.90 or less, and 0.77 or more and 0.80 or less.

[0043] (c) shows the average unevenness height Rc of the uneven surface before the wear resistance test and the unevenness height Rc of the uneven surface after the wear resistance test. This relates to the ratio of average irregularity heights Rc (B3 / A3), which is usually 0.60 or more, preferably 0.70 or more, more preferably 0.74 or more, even more preferably 0.80 or more, and even more preferably 0.84 or more. The upper limit of B3 / A3 is not particularly limited, but is preferably 1.00 or less, 0.95 or less, or 0.90 or less. That is, preferred ranges for B2 / A2 include, for example, 0.60 or more and 1.00 or less, 0.70 or more and 1.00 or less, 0.74 or more and 0.95 or less, 0.80 or more and 0.95 or less, and 0.84 or more and 0.90 or less.

[0044] (d) relates to the ratio (B4 / A4) of the 10-point average roughness Rzjis of the uneven surface after the abrasion resistance test to the 10-point average roughness Rzjis of the uneven surface before the abrasion resistance test, and is usually 0.60 or more, preferably 0.70 or more, more preferably 0.74 or more, even more preferably 0.80 or more, and still more preferably 0.84 or more. The upper limit of B3 / A3 is not particularly limited, but is preferably 1.00 or less, 0.95 or less, or 0.90 or less. That is, preferred ranges of B4 / A4 include, for example, 0.60 to 1.00, 0.70 to 1.00, 0.74 to 0.95, 0.80 to 0.95, and 0.84 to 0.90.

[0045] When friction is applied to a surface having a textured shape, the convex portions are scraped off, typically resulting in a significant decrease in the two-dimensional average roughness Ra, maximum height Rz, average height of convexities and concaves Rc, and ten-point average roughness Rzjis. In contrast, the laminate film according to this embodiment is resistant to wear of the convex portions of the textured surface, and the shape of the convex portions does not change significantly from before the test even after friction is applied in an abrasion resistance test. Therefore, in the laminate film according to this embodiment, the reduction in the two-dimensional average roughness Ra, maximum height Rz, average height of convexities and concaves Rc, and ten-point average roughness Rzjis due to friction is suppressed, and the B1 / A1, B2 / A2, B3 / A3, and B4 / A4 ratios are at or above a certain level. As a result, the laminate film according to this embodiment has excellent scratch resistance, and when used as a writing feel-improving film for a touch panel, the writing feel is not easily deteriorated even with repeated input with a touch pen, and it is possible to maintain a good writing feel similar to that of writing on paper with a writing instrument.

[0046] The laminated film according to the present embodiment satisfies one or more of (a) to (d), and preferably satisfies two or more of (a) to (d), more preferably satisfies three or more of (a) to (d), and even more preferably satisfies all of (a) to (d), in order to enhance the durability of the writing feel when used as a film for improving the writing feel for a touch panel. In these ordinary and preferred aspects, it is preferable that B1 / A1, B2 / A2, B3 / A3, and B4 / A4 of (a) to (d), respectively, are in the preferred ranges described above.

[0047] Methods for forming the uneven surface of the resin layer of the laminated film so as to satisfy (a) to (d) include, in addition to adjusting the average area occupancy of the convex portions to the above range, selecting a resin with high hardness such as (meth)acrylic resin and its crosslinked product as the constituent material of the resin layer; incorporating nanoparticles described below into the resin layer; and, when incorporating fine particles described below into the resin layer, selecting fine particles made of a material with high hardness such as (meth)acrylic resin and its crosslinked product as the fine particles.

[0048] In the present disclosure, the term "(meth)acrylic resin" refers to either or both of an acrylic resin and a methacrylic resin. Similarly, the term "(meth)acrylate" refers to either or both of an acrylate and a methacrylate.

[0049] The above-mentioned abrasion resistance test is carried out on the uneven surface of the resin layer of the laminated film using an abrasive wheel (for example, a Taber abrasive wheel "CS-10" manufactured by Daitron Co., Ltd.) under the conditions of a load of 750 g, a sliding distance (one-way, linear sliding) of 5 cm, a sliding speed of 40 reciprocations / min, and 100 reciprocation cycles.

[0050] The scratch resistance of the laminate film according to this embodiment can also be evaluated by the number of visible scratches generated in the above-mentioned abrasion resistance test. The fewer the number of visible scratches generated in the abrasion resistance test, the better the scratch resistance of the laminate film, and the number is preferably 5 or less, more preferably 3 or less, and even more preferably 0.

[0051] In this disclosure, "visible scratches" means scratches that are 0.1 mm or more in width and 1.0 mm or more in length.

[0052] 1-1-4.Pencil hardness The laminate film according to this embodiment is expected to be used in applications requiring scratch resistance, such as a film for improving the writing feel of a touch panel, and therefore preferably has sufficient pencil hardness. Specifically, the pencil hardness of the laminate film according to this embodiment is preferably H or higher, more preferably 2H or higher, and even more preferably 3H or higher. When the laminate film has a pencil hardness within the above range, it can also function as a protective film for an image display device such as a touch panel when used in the image display device. The upper limit of the pencil hardness of the laminate film according to this embodiment is not particularly limited, but is usually 10H or lower, and may be 9H or lower, or may be 7H or lower.

[0053] Techniques for setting the pencil hardness of the laminated film within the above range include, for example, selecting a resin with high hardness such as (meth)acrylic resin and its crosslinked product as the constituent material of the resin layer; incorporating nanoparticles described below into the resin layer; and, when incorporating fine particles described below into the resin layer, selecting fine particles made of a material with high hardness such as (meth)acrylic resin and its crosslinked product as the fine particles.

[0054] The pencil hardness of the laminated film is measured in accordance with JIS K 5600-5-4:1999 (General test methods for paints - Part 5: Mechanical properties of coatings - Section 4: Scratch hardness (pencil method), established on April 20, 1999) using a pencil scratch hardness tester (for example, "No. 553-M" manufactured by Yasuda Seiki Seisakusho Co., Ltd.). The test is carried out on the resin layer of the laminated film under the conditions of a load of 750 g, a test speed of 30 mm / min, and a test distance of 15 mm.

[0055] 1-1-5. Haze The haze of the laminate film according to this embodiment is preferably 5% or more, more preferably 10% or more, even more preferably 14% or more, and even more preferably 15% or more, in order to obtain antiglare properties. On the other hand, the upper limit of the haze of the laminate film is preferably 50% or less, more preferably 40% or less, even more preferably 35% or less, and even more preferably 30% or less, in order to ensure a transparency sufficient for application to optical applications such as a film for improving the writing feel of a touch panel. That is, preferred ranges for the haze of the laminate film include, for example, 5% to 50%, 10% to 40%, 14% to 35%, and 15% to 30%.

[0056] The haze of the laminated film is measured using a haze meter (for example, "HM-150L2N" manufactured by Murakami Color Research Laboratory Co., Ltd.) in accordance with JIS K 7136:2000 (Method for determining haze of plastics - transparent materials, established on February 20, 2000). At this time, the uneven surface of the resin layer is used as the light incident surface.

[0057] 1-1-6.Total light transmittance From the viewpoint of ensuring a degree of transparency applicable to optical applications such as a touch panel writing feel improving film, the total light transmittance of the laminated film according to this embodiment is preferably 80% or more, more preferably 85% or more, even more preferably 90% or more, and still more preferably 95% or more. On the other hand, the upper limit of the total light transmittance of the laminated film is not particularly limited, and is usually 100% or less.

[0058] The total light transmittance of the laminated film is measured using a haze meter (for example, "HM-150L2N" manufactured by Murakami Color Research Laboratory Co., Ltd.) in accordance with JIS K 7361-1:1997 (Plastics - Test method for total light transmittance of transparent materials - Part 1: Single beam method, established January 20, 1997). In this case, the uneven surface of the resin layer is the light incident surface.

[0059] 1-2. Base material layer The substrate layer is not particularly limited and can be appropriately selected depending on the application of the laminated film. For example, the substrate layer can be a plastic film or a glass plate, and a plastic film is preferred because of its high affinity with the resin layer and interlayer adhesion. The substrate layer can have a single-layer structure or a multi-layer structure.

[0060] Examples of plastic films include polyester films such as polyethylene terephthalate film, polybutylene terephthalate film, and polyethylene naphthalate film; polyolefin films such as polyethylene film, polypropylene film, and polymethylpentene film; cellulose-based films such as cellophane, diacetyl cellulose film, triacetyl cellulose film, and acetyl cellulose butyrate film; vinyl resin films such as polyvinyl chloride film, polyvinylidene chloride film, polyvinyl alcohol film, ethylene-vinyl acetate copolymer film, and polystyrene film; polycarbonate film; polysulfone film; polyether ether ketone film; polyether sulfone film; polyether imide film; fluororesin film; polyamide film; (meth)acrylic resin film; polyurethane resin film; cyclic olefin polymer films such as norbornene polymer film; and cyclic conjugated diene polymer films. Two or more of these plastic films can also be laminated and used as the substrate layer.

[0061] Of these plastic films, polyester film is preferred as the base layer, and polyethylene terephthalate film is more preferred, in terms of high transparency and strength.

[0062] The substrate layer may be subjected to any surface treatment to improve interlayer adhesion between adjacent layers, such as corona treatment, flame treatment, UV ozone treatment, chromic acid treatment, and sandblasting.

[0063] The thickness of the base layer is not particularly limited, but is preferably 25 μm or more, more preferably 55 μm or more, even more preferably 75 μm or more, and is preferably 200 μm or less, more preferably 125 μm or less, even more preferably 100 μm or less. That is, preferred ranges for the base layer include, for example, 25 μm or more and 200 μm or less, 55 μm or more and 125 μm or less, and 75 μm or more and 100 μm or less.

[0064] By setting the thickness of the substrate layer to the above lower limit or more, the above-mentioned pencil hardness is easily exhibited, and when the laminate film is used as a film for improving the writing feel for a touch panel, the influence of the adhesive used for attaching it to the touch panel on the writing feel and the hardness of the touch panel surface can be reduced. Furthermore, by setting the thickness of the substrate layer to the above upper limit or less, appropriate flexibility can be obtained, and therefore the ease of handling of the laminate film according to this embodiment can be improved.

[0065] 1-3.Resin layer The resin layer is a layer formed on the base layer, and has an uneven surface on the side opposite to the base layer. The uneven surface of the resin layer is the layer that comes into contact with a touch pen when the laminated film of this embodiment is used as a writing feel improvement film for a touch panel, so it is preferable that it is the outermost surface of the laminated film, and therefore it is preferable that no layer is formed on the surface of the resin layer opposite the base material layer.

[0066] The method for forming the resin layer is not particularly limited as long as it can form the desired uneven surface, and examples include a method in which a resin layer without an uneven surface is formed on a substrate layer by extrusion molding, coating, etc., and then an uneven shape is formed on the surface of the resin layer opposite the substrate layer by embossing using a stamper and etching, etc.; and a method in which a coating composition containing fine particles having a shape corresponding to the convex portions is applied to the substrate layer, as shown in the examples described below.

[0067] The material constituting the resin layer is not particularly limited, and may be a base resin alone, or a composition containing optional components such as fine particles and nanoparticles, which will be described later, in addition to the base resin.

[0068] The base resin contained in the resin layer is preferably a polymer of a polyfunctional monomer having 2 to 8 polymerizable groups, and more preferably a polymer of a polyfunctional (meth)acrylate having 2 to 8 (meth)acryloyl groups. The base resin may be a homopolymer or a copolymer in which any two or more types of monomers are copolymerized in any ratio.

[0069] Examples of polyfunctional (meth)acrylates include alkylene glycol di(meth)acrylates such as ethylene glycol di(meth)acrylate, propylene glycol di(meth)acrylate, butanediol di(meth)acrylate, neopentyl glycol di(meth)acrylate, and hexanediol di(meth)acrylate; (poly)oxyalkylene glycol di(meth)acrylates such as diethylene glycol di(meth)acrylate, dipropylene glycol di(meth)acrylate, and polyoxytetramethylene glycol di(meth)acrylate; tricyclodecane dimethanol di(meth)acrylate and adamantane di(meth)acrylate; Examples of suitable polyfunctional (meth)acrylates include di(meth)acrylates having a bridged cyclic hydrocarbon group such as acrylate; tri(meth)acrylates such as glycerin tri(meth)acrylate, trimethylolpropane tri(meth)acrylate, trimethylolethane tri(meth)acrylate, pentaerythritol tri(meth)acrylate, and ethoxyltrimethylolpropane tri(meth)acrylate; tetra(meth)acrylates such as pentaerythritol tetra(meth)acrylate; penta(meth)acrylates such as dipentaerythritol penta(meth)acrylate; and hexa(meth)acrylates such as dipentaerythritol hexa(meth)acrylate. Among these, the polyfunctional (meth)acrylate is preferably at least one selected from the group consisting of dipentaerythritol hexa(meth)acrylate and ethoxyltrimethylolpropane tri(meth)acrylate.

[0070] The resin layer preferably contains fine particles. Fig. 2 shows a cross-sectional view of one embodiment of a laminate film having a resin layer containing fine particles. In the laminate film 10 shown in Fig. 2, the fine particles 13b are dispersed in the resin layer and held in the resin layer 13. Covered by the resin material 13c, some of the fine particles 13b protrude from the side of the resin layer 13 opposite the base layer 11, forming convex portions 13d that reflect the shape of the fine particles 13b. The concave-convex surface 13a is formed by the plurality of convex portions 13d.

[0071] From the viewpoint of forming an uneven surface having the above-mentioned two-dimensional average roughness Ra, maximum height Rz, average unevenness height Rc, and ten-point average roughness Rzjis, the average particle size of the microparticles is preferably 1 μm or more, more preferably 3 μm or more, and even more preferably 6 μm or more, and is also preferably 16 μm or less, more preferably 12 μm or less, and even more preferably 10 μm or less. That is, preferred ranges for the average particle size of the fine particles include, for example, 1 μm to 16 μm, 3 μm to 12 μm, and 6 μm to 10 μm.

[0072] In this disclosure, "average particle size" refers to the median diameter (D 50 ) and is measured using a laser diffraction / scattering particle size distribution analyzer.

[0073] The shape of the fine particles is not particularly limited, but is preferably spherical. In the present disclosure, spherical does not only mean a perfect sphere, but also includes shapes having a circular, approximately circular, elliptical, or approximately elliptical cross-sectional shape, such as a prolate sphere and an oblate sphere. However, the fine particles contained in the resin layer are preferably spherical or approximately spherical. Since the shape of the fine particles is reflected in the shape of the convex portions, if the fine particles are spherical or approximately spherical, they can disperse the impact and reduce wear when an impact is applied due to contact with a pointed object such as a touch pen, thereby improving the scratch resistance of the laminate film.

[0074] Materials constituting the fine particles include (meth)acrylic resins, melamine-based resins, acrylic-styrene-based copolymers, polycarbonate-based resins, polyethylene-based resins, polystyrene-based resins, benzoguanamine-based resins, and crosslinked products thereof. In terms of excellent transparency and strength, the fine particles are preferably (meth)acrylic resin particles, more preferably crosslinked (meth)acrylic resin particles, and even more preferably crosslinked polymethyl methacrylate particles (for example, the "Techpolymer SSX series" manufactured by Sekisui Plastics Co., Ltd.).

[0075] When the resin layer contains fine particles, the content of the fine particles in the resin layer is preferably 1 part by mass or more, more preferably 2 parts by mass or more, even more preferably 3 parts by mass or more, even more preferably 4 parts by mass or more, and is preferably 20 parts by mass or less, more preferably 15 parts by mass or less, even more preferably 10 parts by mass or less, and even more preferably 5 parts by mass or less, relative to 100 parts by mass of the base resin. That is, when the resin layer contains fine particles, the preferred range of the content of the fine particles relative to 100 parts by mass of the base resin in the resin layer can be, for example, 1 part by mass or more and 20 parts by mass or less, 2 parts by mass or more and 15 parts by mass or less, 3 parts by mass or more and 10 parts by mass or less, and 4 parts by mass or more and 5 parts by mass or less.

[0076] By setting the content of fine particles in the resin layer within the above range, it becomes easier to adjust the two-dimensional average roughness Ra, maximum height Rz, average height of unevenness Rc, 10-point average roughness Rzjis, and average area occupancy rate of the convex portions of the uneven surface within the above-mentioned preferred ranges.

[0077] The refractive index of the microparticles is preferably the same as or close to that of the base resin. More specifically, the difference between the refractive index of the base resin and that of the microparticles is preferably 0.10 or less, more preferably 0.05 or less, even more preferably 0.03 or less, and is usually 0.00 or more. That is, the preferred range of the difference between the refractive index of the base resin and that of the microparticles is, for example, 0.00 or more and 0.10 or less, 0.00 or more and 0.05 or less, and 0.00 or more and 0.03 or less.

[0078] By setting the difference between the refractive index of the base resin and the refractive index of the fine particles within the above range, a laminated film with low haze can be obtained.

[0079] The resin layer preferably contains nanoparticles having an average particle size of 200 nm or less (hereinafter, sometimes simply referred to as "nanoparticles").

[0080] The average particle size of the nanoparticles is usually 200 nm or less, preferably 100 nm or less, more preferably 50 nm or less, and even more preferably 30 nm or less. Although not particularly limited, the average particle size is preferably 1 nm or more, more preferably 5 nm or more, even more preferably 10 nm or more, and even more preferably 15 nm or more. That is, preferred ranges for the average particle size of the nanoparticles include, for example, ranges of 1 nm to 200 nm, 5 nm to 100 nm, 10 nm to 50 nm, and 15 nm to 30 nm.

[0081] By incorporating nanoparticles of this size into the resin layer, the abrasion resistance of the uneven surface of the resin layer is improved, and as a result, the scratch resistance of the laminated film can be improved.

[0082] Examples of nanoparticles include silica nanoparticles and alumina particles, with silica nanoparticles being preferred because they are highly effective in improving the abrasion resistance of the irregular surface of the resin layer.

[0083] When the resin layer contains nanoparticles, the content of the nanoparticles in the resin layer is preferably 5 parts by mass or more, more preferably 8 parts by mass or more, even more preferably 10 parts by mass or more, and is preferably 40 parts by mass or less, more preferably 30 parts by mass or less, and even more preferably 20 parts by mass or less, relative to 100 parts by mass of the base resin. That is, when the resin layer contains nanoparticles, preferred ranges of the content of the nanoparticles relative to 100 parts by mass of the base resin in the resin layer include, for example, 5 parts by mass or more and 40 parts by mass or less, 8 parts by mass or more and 30 parts by mass or less, and 10 parts by mass or more and 20 parts by mass or less.

[0084] By setting the content of nanoparticles in the resin layer within the above range, it is possible to suppress the influence of the nanoparticles on the two-dimensional average roughness Ra, maximum height Rz, average height of unevenness Rc, and 10-point average roughness Rzjis of the uneven surface, while ensuring the transparency and ease of formation of the resin layer, and to make the laminate film satisfy one or more of the above (a) to (d) and improve the pencil hardness of the laminate film, thereby obtaining a laminate film with excellent scratch resistance.

[0085] The thickness of the resin layer is not particularly limited, but is preferably 2 μm or more, more preferably 3 μm or more, and even more preferably 4 μm or more, and is preferably 7 μm or less, more preferably 6 μm or less, and even more preferably 5 μm or less.

[0086] By setting the thickness of the resin layer to the above lower limit or more, sufficient pencil hardness can be imparted to the laminate film. By setting the thickness of the resin layer to the above upper limit or less, sufficient haze can be ensured, and anti-glare properties can also be obtained. Furthermore, particularly when the convex portions are formed by incorporating fine particles into the resin layer, by setting the thickness of the resin layer to the above upper limit or less, the fine particles are less likely to be buried in the resin layer, and convex portions that reflect the shape of the fine particles are formed. Therefore, when this laminate film is used as a writing feel improving film for a touch panel, it becomes easier to realize a good writing feel like writing on paper with a writing instrument.

[0087] In the present disclosure, the "thickness of the resin layer" refers to the distance between the surface of the resin layer opposite the uneven surface and the zero plane (average plane) described above. The "thickness of the resin layer" does not include the thickness of layers other than the resin layer, such as the substrate layer and other layers described below.

[0088] The resin layer may contain any additives as long as the effects of the present disclosure are not impaired. Examples of the optional additives include fluorine-based antifouling additives, photopolymerization initiators, UV absorbers, antioxidants, light stabilizers, antistatic agents, silane coupling agents, antioxidants, thermal polymerization inhibitors, surfactants, storage stabilizers, plasticizers, lubricants, antifoaming agents, wettability improvers, and coating surface improvers. When the resin layer contains any additive, the amount of the additive added is preferably 5 parts by mass or less, more preferably 3 parts by mass or less, and even more preferably 1 part by mass or less, per 100 parts by mass of the base resin, and is usually more than 0 parts by mass.

[0089] 1-4. Other layers The laminated film according to the present embodiment may have layers other than those described above, as long as the effects of the present disclosure are not impaired. Examples of such layers include a primer layer for improving adhesion between the substrate layer and the resin layer.

[0090] 2.Laminated sheet with protective film A second embodiment of the present disclosure is a laminate sheet having the laminate film according to the first embodiment and a protective film disposed on one or both sides of the laminate film.

[0091] The protective film is not particularly limited, and examples thereof include plastic films such as polyester films such as polyethylene terephthalate films; polyolefin films such as polyethylene films; and thermoplastic polyurethane elastomer films.

[0092] The protective film may have an adhesive layer on one side to enhance adhesion to the laminated film. Examples of materials constituting the adhesive layer of the protective film include ethylene vinyl alcohol, (meth)acrylic resin, and silicone resin. Therefore, a more specific example of the protective film is a multilayer film having a polyethylene film and an adhesive layer containing ethylene vinyl alcohol.

[0093] The thickness of the protective film is not particularly limited, but is preferably 30 μm or more and 125 μm or less, and more preferably 30 μm or more and 80 μm or less.

[0094] FIG. 3 shows a cross-sectional schematic diagram of one embodiment of a laminate sheet according to the present invention. In FIG. 3, a laminate sheet 20 includes a laminate film 10 and protective films 21 disposed on both sides of the laminate film 10. The laminate film 10 includes a base layer 11 and a resin layer 13 having an uneven surface 13a on the side opposite the base layer 11. The protective film 21 includes a protective film base layer 21a and an adhesive layer 21b. One of the protective films 21 is attached to the laminate film 10 such that the adhesive layer 21b contacts the uneven surface 13a of the laminate film 10. The other protective film 21 is attached to the laminate film 10 such that the adhesive layer 21b contacts the surface of the base layer 11 opposite the resin layer 13.

[0095] By disposing a protective film on one or both sides of the laminate film to form a laminate sheet, the laminate film can be protected from damage such as friction and scratches. It is preferable that the protective film is disposed at least on the uneven surface of the laminate film, in order to prevent the convex portions of the resin layer of the laminate film from wearing away before use (for example, during distribution).

[0096] 3.Adhesive laminated sheet A third embodiment of the present disclosure is a laminate sheet having the laminate film according to the first embodiment and an adhesive layer disposed on one or both sides of the laminate film.

[0097] Examples of materials for the adhesive layer include (meth)acrylic resins and epoxy resins.

[0098] The thickness of the adhesive is not particularly limited, but is preferably 25 μm or more and 100 μm or less, and more preferably 25 μm or more and 50 μm or less.

[0099] A cross-sectional schematic diagram of one aspect of the laminate sheet according to this embodiment is shown in Fig. 4. In Fig. 4, the laminate sheet 20 has a laminate film 10 and an adhesive layer 23 disposed on one side of the laminate film 10. The laminate film 10 has a base layer 11 and an uneven surface 13a on the side opposite to the base layer 11. The laminate film 10 has a resin layer 13. The adhesive layer 23 is attached to the laminate film 10 so as to be in contact with the surface of the base layer 11 of the laminate film 10 opposite to the resin layer 13.

[0100] By disposing an adhesive layer on one or both sides of the laminate film to form a laminate sheet, the laminate film can be easily attached to an image display device, etc. For convenience when using the laminate film as an anti-glare film, a film for improving the writing feel for a touch panel, etc., the adhesive layer is preferably disposed on the surface of the base layer opposite the resin layer 13. Furthermore, in the laminate sheet according to this embodiment, it is also preferable that a release sheet, which is a plastic film or paper that has been subjected to a release treatment using a silicone resin or the like, is disposed on the adhesive layer.

[0101] 4. Image display device A third embodiment of the present disclosure is an image display device including the laminate film according to the first embodiment. The image display device is not particularly limited, and examples thereof include liquid crystal display devices, organic electroluminescent (organic EL) display devices, electronic paper, electronic notebooks (also called digital notebooks or electronic memo pads), and electronic whiteboards. When these image display devices are touch panels, as described above, the laminate film according to the first embodiment is preferred because it functions as a film for improving writing feel and its excellent scratch resistance allows a good writing feel similar to that of writing on paper with a writing implement to be maintained for a long period of time. As touch panel-type image display devices, electronic paper and electronic notebooks (also called digital notebooks or electronic memo pads) are particularly preferred.

[0102] In this embodiment, the image display device is preferably one in which the laminate film according to the first embodiment is attached to the display surface thereof directly or via an adhesive layer. In this case, the image display device may be one in which the laminate film is attached to the display surface thereof via an adhesive layer of the laminate sheet according to the third embodiment. [Example]

[0103] The present disclosure will be explained in more detail below using examples, but the present disclosure is not limited to the following examples as long as it does not deviate from the gist of the disclosure.

[0104] 〔reagent〕 The materials used in the coating composition for forming the resin layer are as follows. DPHA: Dipentaerythritol hexaacrylate, manufactured by Daicel Allnex Co., Ltd. AU-230: Silicone-based UV-curable anti-glare coating agent, manufactured by Tokushiki Co., Ltd. AS-201S: Silicone-based UV-curable hard coating agent, manufactured by Tokushiki Co., Ltd. CAP: Cellulose acetate propionate BYK 3519: Silica nanoparticle dispersion (silica nanoparticle content: 40% by mass, average silica nanoparticle diameter: 20 nm, solvent: ethoxyltrimethylolpropane triacrylate), manufactured by BYK Omnirad 127: Photopolymerization initiator, manufactured by IGM Resins BV Techpolymer SSX-108: Cross-linked polymethyl methacrylate spherical particles (average particle size: 8 μm, refractive index: 1.49), manufactured by Sekisui Plastics Co., Ltd. Techpolymer SSX-115HXE: Cross-linked polymethyl methacrylate spherical particles (average particle size: 15 μm, refractive index: 1.49), manufactured by Sekisui Plastics Co., Ltd. KY1203: Fluorine-based antifouling additive (active ingredient concentration: 20% by mass), manufactured by Shin-Etsu Chemical Co., Ltd. MEK: Methyl ethyl ketone 1-BuOH: 1-butanol PGM: Propylene glycol monomethyl ether

[0105] [Evaluation method] (Haze) The haze of the laminated film was measured using a haze meter ("HM-150L2N" manufactured by Murakami Color Research Laboratory Co., Ltd.) in accordance with JIS K 7136:2000 (Determination of haze for plastics - transparent materials, established on February 20, 2000). At this time, the uneven surface of the resin layer was used as the light incident surface.

[0106] (Total light transmittance) The total light transmittance of the laminated film was measured using a haze meter ("HM-150L2N" manufactured by Murakami Color Research Laboratory Co., Ltd.) in accordance with JIS K 7361-1:1997 (Plastics - Test method for total light transmittance of transparent materials - Part 1: Single beam method, established January 20, 1997). At this time, the uneven surface of the resin layer was used as the light incident surface.

[0107] (Average area occupancy of convex parts) Using an optical interference surface profiler (Hitachi High-Tech Corporation's "VertScan2.0 R3300G Lite"), the uneven surface of the resin layer of a 6 cm x 6 cm sample cut from the laminate film was measured over 10 fields of view with a measurement area of ​​189.46 μm x 252.5 μm. The objective lens magnification was 50x. The sample was sandwiched between two metal frames so that the measurement Y-axis was aligned with the longitudinal direction of the laminate film, and was set on the stage after removing any slack or curl. Image processing and analysis using surface analysis software (VS-Viewer, manufactured by Ryoka Systems Co., Ltd.) were used to detect convex portions with a height of 0.3 μm or more, and their occupied area was calculated. This occupied area was divided by the measured area to calculate the area occupied by the convex portions. The area occupied by the convex portions was calculated for all 10 fields of view, and the average value was calculated as the average area occupied by the convex portions. Image processing conditions Interpolation process: Full interpolation (only data with 90% or more valid pixels before interpolation is valid) Surface correction: 4th order correction ·Analysis conditions Analysis type: sudden analysis Height threshold setting: 0.3 μm Reference height: Zero plane (average plane) Re-binarization: No Particle shaping: No

[0108] (Pencil hardness) The pencil hardness of the laminated film was measured using a pencil scratch hardness tester (No. 553-M, manufactured by Yasuda Seiki Seisakusho Co., Ltd.) in accordance with JIS K 5600-5-4:1999 (General test methods for paints - Part 5: Mechanical properties of coating films - Section 4: Scratch hardness (pencil method), established on April 20, 1999). The test was carried out on the resin layer of the laminated film under the following conditions: load 750 g, test speed 30 mm / min, and test distance 15 mm.

[0109] (Number of scratches after abrasion resistance test) An abrasion resistance test was conducted on the uneven surface of the resin layer of the laminated film using a Taber abrasion wheel ("CS-10" manufactured by Daitron Co., Ltd.) under the following conditions: load 750 g, sliding distance (one way, linear sliding) 5 cm, sliding speed 40 reciprocations / min, and number of reciprocations 100. After the abrasion resistance test, the resin layer of the laminated film was observed and the number of visible scratches was counted.

[0110] (Writing feel) Eight trained panelists used a NintendoDS (registered trademark) stylus to touch the resin layer surface. The writing feel was evaluated and judged according to the following criteria.

[0111] Evaluation criteria A: More than five panelists felt that the writing experience was similar to the sensation of writing with a pencil on paper. B: Fewer than four panels felt that the writing experience was similar to the sensation of writing with a pencil on paper.

[0112] (Surface roughness of resin layer) The two-dimensional average roughness Ra, maximum height Rz, average unevenness height Rc, and ten-point average roughness Rzjis of the uneven surface of the resin layer were measured in accordance with JIS B 0601:2013 (Geometrical Product Specifications (GPS) - Surface Texture: Profile Curve Method - Terms, Definitions, and Surface Texture Parameters, revised March 21, 2013) using a surface roughness measuring instrument (SURFCOM 1400G-12, manufactured by Tokyo Seimitsu Co., Ltd.) under the following conditions: Surface roughness measurement conditions Measurement length: 10 mm Measurement speed: 0.3mm / sec Cutoff wavelength (λc): 0.8 mm Probe tip radius: 2 μm Cone angle: 90°

[0113] Example 1 The components listed in Table 1 were mixed to obtain a coating composition. This coating composition was applied to a polyethylene terephthalate film ("O321E75" manufactured by Mitsubishi Chemical Corporation, thickness: 75 μm) using a wire bar, and then heat-treated in an oven heated to a temperature in the range of 80°C to 100°C to obtain a dried coating film. Next, an ultraviolet irradiation device (manufactured by Ushio Inc.) was used to apply 500 mJ / cm to this dried coating film. 3 A laminated film was produced by irradiating the film with ultraviolet light. Various physical properties of the resulting laminated film were evaluated. The results are shown in Tables 2 and 3.

[0114] [Examples 2-3, Comparative Examples 1-3] A laminated film was produced in the same manner as in Example 1, except that the formulation of the coating composition was changed as shown in Table 1, and various physical properties were evaluated. The results are shown in Tables 2 and 3.

[0115] [Table 1]

[0116] [Table 2]

[0117] [Table 3]

[0118] From Examples 1 to 3, by setting the average area occupancy of the convex portions of the resin layer to 6% or more, B1 / A The results show that the average area occupancy of the convex portions of the resin layer of the laminated film is 6% or more, and the abrasion resistance can be improved by increasing the average area occupancy of the convex portions of the resin layer of the laminated film to 6% or more. [Explanation of symbols]

[0119] 10 Laminated film 11 Base material layer 13 Resin layer 13a Uneven surface 13b Fine particles 13c resin material 13d Convex part 20 Laminated Sheet 21 Protective film 21a Protective film base layer 21b Adhesive layer 23 Adhesive layer

Claims

1. a base layer; and a resin layer formed on the base layer, the resin layer having an uneven surface on the opposite side to the base layer, the uneven surface having an uneven shape; When the surface shape of the uneven surface is measured with an optical interference type surface shape measuring device over a measurement area of ​​189.46 μm × 252.5 μm, the average area occupancy of convex portions having a height of 0.3 μm or more is 6% or more, A laminated film that satisfies one or more of the following (a) to (d) when an abrasion resistance test is conducted on the uneven surface using an abrasive wheel under the conditions of a load of 750 g, a sliding distance of 5 cm, a sliding speed of 40 reciprocations per minute, and a number of reciprocations of 100: (a) B1 / A1 ≧ 0.80 (b) B2 / A2 ≧ 0.60 (c) B3 / A3 ≧ 0.60 (d) B4 / A4 ≧ 0.60 (In formulas (a) to (d), A1 is the two-dimensional average roughness Ra of the roughness curve element of the uneven surface before the abrasion resistance test; B1 is the two-dimensional average roughness Ra of the roughness curve element of the uneven surface after the abrasion resistance test; A2 is the maximum height Rz of the roughness curve element of the uneven surface before the abrasion resistance test; B2 is the maximum height Rz of the roughness curve element of the uneven surface after the abrasion resistance test; A3 is the average unevenness height Rc of the roughness curve elements of the uneven surface before the abrasion resistance test; B3 is the average unevenness height Rc of the roughness curve elements of the uneven surface after the abrasion resistance test; A4 is the 10-point average roughness Rzjis of the roughness curve element of the uneven surface before the abrasion resistance test; B4 is the 10-point average roughness Rzjis of the roughness curve element of the uneven surface after the abrasion resistance test.

2. 2. The laminated film according to claim 1, wherein the number of scratches having a width of 0.1 mm or more and a length of 1.0 mm or more generated in the abrasion resistance test is 5 or less.

3. The laminated film according to claim 1, which has a pencil hardness of H or more as measured in accordance with JIS K 5600-5-4:1999.

4. The laminated film according to claim 1, having a total light transmittance of 85% or more.

5. The laminated film according to claim 1, which has a haze of 5% or more and 35% or less.

6. The laminated film according to claim 1 , wherein the resin layer contains fine particles.

7. The laminated film according to claim 6, wherein the fine particles have an average particle size of 1 μm or more and 16 μm or less.

8. 7. The laminated film according to claim 6, wherein the difference between the refractive index of the base resin contained in the resin layer and the refractive index of the fine particles is 0.00 or more and 0.10 or less.

9. The laminated film according to claim 1 , wherein the resin layer contains nanoparticles having an average particle size of 200 nm or less.

10. The laminated film according to claim 1 , wherein the substrate layer is a polyester film.

11. The laminated film according to claim 1, which is a film for improving writing feel on a touch panel.

12. A laminate sheet comprising the laminate film according to any one of claims 1 to 11 and a protective film disposed on at least one surface of the laminate film.

13. A laminate sheet comprising the laminate film according to any one of claims 1 to 11 and an adhesive layer disposed on at least one surface of the laminate film.

14. An image display device comprising the laminate film according to any one of claims 1 to 11.

Images