Optical film winding, optical film, optical component, image display device, method for manufacturing an optical film winding, and method for inspecting the quality of an optical film winding.

Abstract

The present invention provides an optical film winding body in which scratches and dents are suppressed or prevented, even when the winding hardness is high. [Solution] A winding of optical film 10, wherein the outermost layer of the optical film winding 100 has an average value H of plastic durometer hardness. a The plastic durometer hardness H1 at the center point is characterized by satisfying the following formulas (1) and (2). H a ≥40(1) 0 ≤ |(H a -H1)| / H a ≤0.1(2)

Description

[Technical Field]

[0001] The present invention relates to an optical film winding, an optical film, an optical component, an image display device, a method for manufacturing an optical film winding, and a method for inspecting the quality of an optical film winding. [Background technology]

[0002] Optical films are often manufactured as long-length optical films for reasons such as manufacturing efficiency, and are frequently stored as wound bodies of these long-length optical films (Patent Document 1, etc.). [Prior art documents] [Patent Documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2014-108849 [Overview of the Initiative] [Problems that the invention aims to solve]

[0004] However, if the winding tension of the optical film winding body (the pressure or tension applied to the optical film) varies greatly from place to place and is highly inconsistent, then, for example, if foreign matter gets caught in a part where the winding tension is high (pressure is concentrated), there is a risk of dents or scratches occurring. On the other hand, if the winding tension of the optical film winding body is loosened (the tension applied to the optical film is loosened) in an attempt to prevent the occurrence of dents and scratches, then defects (such as wrinkles) may occur in the optical film due to winding misalignment, and there is a risk that the optical film will not be able to be supplied to the next process.

[0005] Therefore, the present invention aims to provide an optical film winding, an optical film, an optical component, an image display device, a method for manufacturing an optical film winding, and a method for inspecting the quality of an optical film winding, in which scratches and dents are suppressed or prevented even when the winding hardness is high and hard. [Means for solving the problem]

[0006] To achieve the above objective, the optical film winding body of the present invention is A winding of optical film, In the outermost layer of the aforementioned optical film winding, the average value of the plastic durometer hardness H a The plastic durometer hardness H1 at the center point is characterized by satisfying the following formulas (1) and (2). H a ≥40 (1) 0 ≤ |(H a -H1)| / H a ≤0.1 (2) In the above formulas (1) and (2), H1 is the plastic durometer hardness [N / m] at the center point in the width direction on the outermost layer of the optical film winding, directly opposite the end of the winding of the optical film winding. H a This is the average value [N / m] of the plastic durometer hardness at five points in the width direction opposite to the end of the winding of the optical film: a point 10 mm from one end, a point 1 W / 4 from the one end, the center point, a point 1 W / 4 from the other end, and a point 10 mm from the other end. However, W is the width [m] of the optical film opposite to the end of the winding of the optical film.

[0007] The optical film of the present invention is an optical film obtained by unwinding the optical film winding described above.

[0008] The optical component of the present invention is an optical component that includes the optical film of the present invention.

[0009] The image display device of the present invention is an image display device that includes the optical film of the present invention or the optical component of the present invention.

[0010] The method for manufacturing an optical film winding of the present invention is as follows: The above-mentioned method for manufacturing an optical film winding body is described below. The process includes a winding step of winding the optical film to produce the optical film winding body, In the winding process, the average value H of the plastic durometer hardness is measured at the outermost layer of the optical film winding body. a The optical film is wound such that the plastic durometer hardness H1 at the center point satisfies the above formulas (1) and (2).

[0011] The present invention provides a method for inspecting the quality of an optical film winding, A method for inspecting the quality of an optical film winding, In the outermost layer of the aforementioned optical film winding, the average value of the plastic durometer hardness H a The method is characterized by confirming by measurement whether the plastic durometer hardness H1 at the center point satisfies the above formulas (1) and (2). [Effects of the Invention]

[0012] According to the present invention, it is possible to provide an optical film winding body, an optical film, an optical component, an image display device, a method for manufacturing an optical film winding body, and a method for inspecting the quality of an optical film winding body, in which the occurrence of scratches and dents is suppressed or prevented even if the winding hardness is high and hard. [Brief explanation of the drawing]

[0013] [Figure 1] Figure 1 is a perspective view showing an example of an optical film winding body according to the present invention. [Figure 2] Figure 2 shows the same optical film winding as in Figure 1. Figure 2(a) is a side view. Figure 2(b) is a top view. [Figure 3] Figure 3 is a cross-sectional view showing an example of the optical film of the present invention. [Figure 4] Figure 4 shows an example of winding misalignment in the optical film winding body of the present invention. [Modes for carrying out the invention]

[0014] Next, the present invention will be described more specifically with reference to examples. However, the present invention is not limited in any way by the following description.

[0015] In the optical film wound body of the present invention, for example, the optical film may be an optical film having a plastic deformation amount of 85 nm or less and an elastic recovery rate of 80% or more when indented by the nanoindentation method. In the present invention, the method for measuring the plastic deformation amount and the elastic recovery rate by the nanoindentation method is not particularly limited, but can be measured, for example, by the measurement method described in the examples below.

[0016] In the optical film wound body of the present invention, for example, the relationship between the width and the length of the optical film may satisfy the following mathematical formula (3). 40≦L / W≦20000 (3) In the above mathematical formula (3), W is the width [m] of the optical film, L is the length [m] of the optical film.

[0017] In the optical film wound body of the present invention, for example, in the outermost layer of the optical film wound body, the plastic durometer hardness and the thickness of the optical film at the measurement point of the plastic durometer hardness may satisfy the relationship of the following mathematical formula (4). In the present invention, the method for measuring the plastic durometer hardness and the thickness is not particularly limited, but can be measured, for example, by the measurement method described in the examples below. 0.25≦H a / D a ≦7 (4) In the above mathematical formula (4), H aThis is the average value [N / m] of the plastic durometer hardness at five points in the width direction opposite to the end of the winding of the optical film: a point 10 mm from one end, a point 1 W / 4 from the one end, the center point, a point 1 W / 4 from the other end, and a point 10 mm from the other end. However, W is the width [m] of the optical film opposite to the end of the winding of the optical film. D a This is the average value [μm] of the optical film thickness at the five points that are measurement points for the plastic durometer hardness.

[0018] The optical film winding body of the present invention may, for example, be an optical film having irregularities on its surface.

[0019] In the optical film winding body of the present invention, for example, the optical film may be an anti-glare film.

[0020] In the optical film winding body of the present invention, for example, the optical film may be a hard-coated film.

[0021] In the optical film winding body of the present invention, for example, the optical film may be an anti-glare hard coat film.

[0022] The optical component of the present invention may be, for example, a polarizing plate.

[0023] In the method for manufacturing an optical film winding of the present invention, for example, the optical film may be an optical film in which the amount of plastic deformation when pressed by the nanoindentation method is 85 nm or less and the elastic recovery rate is 80% or more.

[0024] In the method for manufacturing an optical film winding body of the present invention, for example, the relationship between the width and length of the optical film may satisfy the above formula (3).

[0025] In the method for manufacturing an optical film winding of the present invention, for example, in the winding step, the optical film may be wound such that the plastic durometer hardness and the thickness of the optical film at the measurement point of the plastic durometer hardness satisfy the relationship of formula (4) in the outermost layer of the optical film winding.

[0026] In the method for manufacturing an optical film winding body of the present invention, for example, the optical film may be an optical film having irregularities on its surface.

[0027] In the method for manufacturing an optical film winding body of the present invention, for example, the optical film may be an anti-glare film.

[0028] In the method for manufacturing an optical film winding body of the present invention, for example, the optical film may be a hard-coated film.

[0029] In the method for manufacturing an optical film winding body of the present invention, for example, the optical film may be an anti-glare hard coat film.

[0030] The method for inspecting the quality of an optical film winding according to the present invention may, for example, involve measuring whether the optical film is an optical film in which the amount of plastic deformation when pressed by the nanoindentation method is 85 nm or less and the elastic recovery rate is 80% or more.

[0031] The method for inspecting the quality of an optical film winding according to the present invention may, for example, involve measuring whether the relationship between the width and length of the optical film satisfies the above formula (3).

[0032] The quality inspection method for an optical film winding of the present invention may, for example, involve measuring whether the plastic durometer hardness and the thickness of the optical film at the measurement point of the plastic durometer hardness satisfy the relationship of formula (4) in the outermost layer of the optical film winding.

[0033] The method for inspecting the quality of an optical film winding according to the present invention may, for example, involve an optical film having irregularities on its surface.

[0034] The present invention's method for inspecting the quality of an optical film winding may, for example, involve using an anti-glare film as the optical film.

[0035] The present invention's method for inspecting the quality of an optical film winding may, for example, involve using a hard-coated optical film.

[0036] The present invention's method for inspecting the quality of an optical film winding may, for example, use an anti-glare hard-coat film as the optical film.

[0037] The optical component of the present invention may be, for example, a polarizing plate.

[0038] In this invention, unless otherwise specified, "weight" and "mass" may be interpreted as interchangeable. For example, "parts of mass" may be interpreted as "parts of weight," "parts of weight" may be interpreted as "parts of mass," "mass%" may be interpreted as "weight%," and "weight%" may be interpreted as "mass%."

[0039] [1. Winding of optical film] The winded optical film of the present invention will be described in more detail below, with examples.

[0040] Figure 1 shows a perspective view of an example of the optical film winding body of the present invention. As shown in the figure, this optical film winding body 100 is a winding of optical film 10. At the outermost layer of the optical film winding body 100, the average value [N / m] of the plastic durometer hardness at five points in the width direction opposite to the end of the winding of the optical film winding body is H aLet the hardness be [N / m]. The five measurement points and the plastic durometer hardness at each measurement point are as follows: That is, the center point in the width direction opposite to the end of the winding of the optical film winding body is defined as h1, and the plastic durometer hardness at h1 is defined as H1 [N / m]. The point in the width direction at a distance of 10 mm from one end is defined as h 21 to, h 21 The plastic durometer hardness in H 21 Let [N / m]. The point h is at a distance of W / 4 from one end in the width direction. 11 to, h 11 The plastic durometer hardness in H 11 Let it be [N / m]. In the width direction, the point at a distance of 10 mm from the other end is h 22 to, h 22 The plastic durometer hardness in H 22 Let [N / m]. The point h is the distance from the other end in the width direction of W / 4. 12 to, h 12 The plastic durometer hardness in H 12 Let [N / m] be the value. However, W is the width [m] of the optical film on the opposite side from the end of the winding of the optical film winding body. h1, h 21 h 11 h 22 h 12 Plastic durometer hardness H1, H at 5 points 21 H 11 H 22 H 12 The average value [N / m] is H a [N / m] is the value of the plastic durometer hardness. a [N / m] and the plastic durometer hardness H1 [N / m] at the center point h1 satisfy the above formulas (1) and (2).

[0041] In this invention, "plastic durometer hardness" refers to the durometer hardness according to the JIS standard JIS K 6253, and is the reaction force when a roll (winding body) is pressed from the outside in the direction of the winding core with a constant force. In this invention, the method for measuring plastic durometer hardness is not particularly limited, but for example, it can be measured by the measurement method specified in JIS K 6253.

[0042] The five measurement points for the plastic durometer hardness in the above formulas (1) and (2) are, for example, h1, h as explained in Figure 1. 21 h 11 h 22 h 12 As shown above. Next, these h1, h explained in Figure 1 21 h 11 h 22 h 12 The five measurement points will be further explained using Figure 2. Figure 2 shows the same optical film winding as in Figure 1. Figure 2(a) is a side view. Figure 2(b) is a top view. In Figure 2(a), 100A indicates the position of the winding end tip of the winding body 100 at the outermost layer of the winding body 100. Also in the same figure, 100B indicates the position of the winding end tip 100A at the outermost layer of the winding body 100. Figure 2(b) shows the five measurement points h1, h in the width direction at the position 100B, which is directly opposite the winding end tip 100A. 21 h 11 h 22 h 12 This shows the positional relationship. h1 is the center point in the width direction at position 100B. That is, as shown in the figure, if the width at position 100B is W [m], then the distance from one end in the width direction at position 100B (right end in the figure) to h1 is W / 2, and the distance from the other end (left end in the figure) to h1 is also W / 2. 21 As shown in the figure, this is the point at position 100B, at a distance of 10 mm from one end (the right end in the figure) in the width direction. 11 As shown in the figure, this is the point at position 100B where the distance from one end (the right end in the figure) is W / 4 in the width direction. Therefore, from the center point h1 to h11 The distance to h is also W / 4, as shown in the diagram. 22 This is the point at position 100B, where the distance from the other end (the left end in the diagram) is 10 mm in the width direction. 12 This is the point at position 100B where the distance from the other end (the left end in the diagram) is W / 4 in the width direction. Therefore, from the center point h1 to h 12 The distance to is also W / 4 as shown in the figure. As explained in Figure 1, h1, h 21 h 11 h 22 h 12 The plastic durometer hardness at these five points is H1, H 21 H 11 H 22 H 12 [N / m], H1, H 21 H 11 H 22 H 12 The average value [N / m] is H a [N / m] is the value of the plastic durometer hardness. a [N / m] and the plastic durometer hardness H1 [N / m] at the center point h1 satisfy the above formulas (1) and (2).

[0043] In the optical film winding body of the present invention, the average value H of the plastic durometer hardness a [N / m] is 40 or more as shown in formula (1) above, but may be 45 or more, 50 or more, 55 or more, or 60 or more, for example, 100 or less, 90 or less, 80 or less, or 70 or less. In order to prevent defects in the optical film due to winding misalignment (e.g., wrinkles), H a [N / m] must be 40 or more. On the other hand, from the viewpoint of preventing deformation of the coiled state and preventing the occurrence of pinpoint indentations, H a It is preferable that the [N / m] value is not too large.

[0044] In the optical film winding body of the present invention, |(H a -H1)| / H aAs shown in formula (2) above, is between 0 and 0.1, but may also be, for example, 0.01 or more, 0.02 or more, 0.03 or more, or 0.04 or more, or for example, 0.09 or less, 0.08 or less, 0.07 or less, or 0.06 or less. |(H a -H1)| / H a A value of 0.1 or less indicates that there is little variation in the winding hardness of the optical film winding body depending on the location, and that there is little uniformity. The optical film winding body has high winding hardness (as shown in formula (1) above), and the variation in winding hardness depending on the location is small, and there is little uniformity (as shown in formula (2) above), so even if the winding hardness is high and hard, the occurrence of scratches and dents is suppressed or prevented in the optical film winding body of the present invention.

[0045] In the optical film winding of the present invention, the optical film may, for example, have a plastic deformation amount of 85 nm or less when pressed by the nanoindentation method, as described above. Furthermore, the optical film may, for example, have an elastic recovery rate of 80% or more when pressed by the nanoindentation method, as described above. Because the optical film itself is hard and resistant to deformation in this way, point-like deformation defects such as dents can be suppressed or prevented. The plastic deformation amount may be, for example, 80 nm or less, 70 nm or less, 60 nm or less, or 50 nm or less, and the lower limit is not particularly limited, but may be, for example, 0 nm or a value greater than 0 nm, and may be, for example, 10 nm or more. The elastic recovery rate may be, for example, 85% or more, or 90% or more, and the upper limit is not particularly limited, but may be, for example, 100% or less, or 95% or less.

[0046] The method for measuring the amount of plastic deformation and the elastic recovery rate is not particularly limited, but can be measured, for example, by the measurement method described in the embodiments below.

[0047] As described above, the optical film winding of the present invention may have a value L / W of 40 or more and 20000 or less (formula (3) above), which is obtained by dividing the length L [m] of the optical film by the width W [m] of the optical film. In order to suppress or prevent the problem of winding misalignment occurring when transporting the winding due to the optical film being too narrow or too long, it is preferable that L / W be 20000 or less. In order to not impair the productivity of the optical film winding due to the optical film being too wide or too short, it is preferable that L / W be 40 or more. L / W may be, for example, 50 or more, 100 or more, 500 or more, or 1000 or more, and may also be, for example, 15000 or less, 10000 or less, 5000 or less, or 3000 or less.

[0048] As described above, the optical film winding body of the present invention has an average value H of plastic durometer hardness at its outermost layer. a [N / m] is the average value D of the thickness of the optical film at the measurement point of the plastic durometer hardness. a The value H divided by [μm] a / D a However, it may be 0.25 or more and 7 or less (formula (4) above). From the viewpoint of suppressing or preventing wrinkles and other marks from easily remaining on the optical film winding itself, or an imbalance in the hardness of the optical film winding, H a / D a It is preferable that the ratio is 7 or less. From the viewpoint of suppressing or preventing risks such as wrinkles and winding misalignment caused by the winding of the optical film being too loose, H a / D a It is preferable that the value is 0.25 or higher. a / D a For example, it may be 0.3 or higher, 0.40 or higher, 0.45 or higher, 1.0 or higher, or 2.0 or higher, and for example, it may be 6.0 or lower, 5.0 or lower, 4.0 or lower, or 3.0 or lower.

[0049] [2. Optical film] Next, the optical film in the optical film winding body of the present invention (hereinafter sometimes referred to as "the optical film of the present invention") will be specifically described with examples.

[0050] The optical film of the present invention is not particularly limited, but as mentioned above, it may be an optical film having irregularities on its surface. An optical film having irregularities on its surface is slippery, and when used as an optical film winding, there is a risk of winding misalignment. However, with the optical film winding of the present invention, even if the winding hardness is greatly increased to suppress or prevent winding misalignment, the occurrence of scratches and dents can be suppressed or prevented. Examples of optical films having irregularities on their surface are not particularly limited, but include anti-glare films, anti-glare hard coat films, anti-blocking treated films, shaped films, anti-reflective films, phase difference films, surface protection films, separators (release films), etc. The optical film of the present invention may be, for example, an anti-glare film, a hard coat film, an anti-glare hard coat film, etc., as mentioned above, or it may be an anti-blocking treated film, a shaped film, or a film with a flat surface without irregularities, as long as the occurrence and suppression of winding misalignment and dent defects can be prevented.

[0051] If the optical film of the present invention has irregularities on its surface, the shape of these irregularities is not particularly limited.

[0052] The structure of the optical film of the present invention is not particularly limited, but may be, for example, a structure in which a functional layer (e.g., a coating layer) is formed on a light-transmitting substrate. The light-transmitting substrate (hereinafter sometimes referred to as "light-transmitting substrate (A)") is not particularly limited, but may be, for example, as described below. The functional layer is not particularly limited, but may be, for example, an anti-glare layer, a hard coat layer, an anti-glare hard coat layer, an anti-reflective layer, a phase difference adjustment layer, a release film (separator), etc. The functional layer (hereinafter sometimes referred to as "functional layer (B)") may be, for example, a resin layer, and may be a functional layer composed of, for example, a thermosetting resin, an ionizing radiation curing resin, etc.

[0053] Figure 3 shows a cross-sectional view of an example of the optical film of the present invention. As shown in the figure, this optical film 10 has a functional layer (B) 12 laminated on one side of a light-transmitting substrate (A) 11. In the optical film 10 of Figure 3, the functional layer (B) 12 is an anti-glare hard coat layer. The anti-glare hard coat layer (B) 12 contains particles 12b and a thixotropy imparting agent 12c in the functional layer forming resin 12a.

[0054] In this invention, the functional layer (B) may be formed solely of resin, for example, but may also contain other components. The other components are not particularly limited and may consist of one or more types, and may include particles, thixotropy imparting agents, etc., as shown in Figure 3.

[0055] Furthermore, in the functional layer (B), the surface opposite to the light-transmitting substrate (A) may be flat, but may also have irregularities, as shown in Figure 3. As mentioned above, optical films with irregularities on their surface tend to be slippery, and there is a risk of winding misalignment when they are made into an optical film winding body. However, with the optical film winding body of the present invention, even if the winding hardness is greatly increased to suppress or prevent winding misalignment, the occurrence of scratches and dents can be suppressed or prevented.

[0056] The light-transmitting substrate (A) and the functional layer (B) will be described further below with examples.

[0057] The light-transmitting substrate (A) is not particularly limited, but examples include a transparent plastic film substrate. The transparent plastic film substrate is not particularly limited, but it is preferably one that has excellent visible light transmittance (preferably 90% or more) and excellent transparency (preferably one with a haze value of 1% or less), and an example is the transparent plastic film substrate described in Japanese Patent Application Publication No. 2008-90263. As the transparent plastic film substrate, one with low optical birefringence is preferably used. The optical film of the present invention can also be used as a protective film for a polarizer, for example. In this case, the transparent plastic film substrate is preferably a film formed from triacetylcellulose (TAC), polycarbonate, acrylic polymer, polyolefin having a cyclic or norbornene structure, etc. Furthermore, as will be described later in the present invention, the transparent plastic film substrate may be the polarizer itself. With such a configuration, a protective layer made of TAC, etc., is not required, and the structure of the polarizer can be simplified, thereby reducing the number of manufacturing steps for the polarizer or image display device and improving production efficiency. Furthermore, with this configuration, the polarizing plate can be made even thinner. If the transparent plastic film substrate is a polarizer, for example, the functional layer (B) may also serve as a protective layer. Also, with this configuration, the optical film, for example, when mounted on the surface of a liquid crystal cell, will also function as a cover plate.

[0058] In the present invention, the thickness of the light-transmitting substrate (A) is not particularly limited, but considering factors such as strength, workability including handling, and thinness, it is, for example, in the range of 10 to 500 μm, 20 to 300 μm, or 30 to 200 μm. The refractive index of the light-transmitting substrate (A) is not particularly limited. The refractive index is, for example, in the range of 1.30 to 1.80 or 1.40 to 1.70.

[0059] The optical film of the present invention may, for example, include an acrylic resin in the light-transmitting substrate (A).

[0060] In the optical film of the present invention, for example, the light-transmitting substrate (A) may be an acrylic film.

[0061] The optical film of the present invention may, for example, have irregularities on the surface opposite to the light-transmitting substrate in the functional layer (B) as described above. Also, for example, the external haze value due to the irregularities may be 5% or more. In highly anti-glare films, the overall appearance may become blurred and black and white patterns may easily occur. From the viewpoint of suppressing or preventing this, and from the viewpoint of suppressing reflections, it is preferable that the external haze value be as large as possible. On the other hand, from the viewpoint of suppressing or preventing a decrease in display characteristics (for example, the image becomes unclear, the contrast in dark places decreases, etc.), it is preferable that the external haze value is not too large. The external haze value is not particularly limited, but for example it may be 5% or more, 10% or more, 15% or more, or 20% or more, and for example it may be 50% or less, 45% or less, 40% or less, or 35% or less. In the present invention, the method for measuring the external haze value is not particularly limited, but for example it can be measured by the measurement methods (1) to (3) below. (1) The total haze value of the optical film of the present invention is measured according to the method in accordance with JIS K 7136. (2) A translucent adhesive is laminated on the side of the functional layer (B) of the optical film described in (1) that is opposite to the light-transmitting substrate (A), and a COP film (manufactured by Zeon Corporation, trade name ZEONOR film) is then attached on top of it to create a laminate. When this laminate is measured using the same measurement method as the measurement method for the total haze value in accordance with JIS K 7136 (i.e., the measurement method described in (1)), the internal haze value of the optical film described in (1) can be obtained. This internal haze value is the haze value obtained by removing the influence of the irregularities on the outermost surface of the functional layer (B) from the total haze value described in (1). (3) The value obtained by subtracting the internal haze value measured in (2) from the total haze value measured in (1) is taken as the external haze value of the optical film in (1).

[0062] In the optical film of the present invention, the resin contained in the functional layer (B) is not particularly limited, but may include, for example, an acrylate resin (also called an acrylic resin).

[0063] The optical film of the present invention may, for example, include a urethane acrylate resin in the functional layer (B).

[0064] The optical film of the present invention may, for example, have a functional layer (B) formed from a copolymer of a functional oligomer and a monomer. The functional oligomer is not particularly limited, but examples include curable urethane acrylate resin. Examples of curable urethane acrylate resins include the trade names "UV-1700TL" and "UT-7314" manufactured by Mitsubishi Chemical Corporation. The monomer is not particularly limited, but examples include polyfunctional acrylate. Examples of polyfunctional acrylates include the trade name "M-920" manufactured by Toagosei Co., Ltd.

[0065] In the optical film of the present invention, for example, the resin contained in the functional layer (B) may be a copolymer of a curable urethane acrylate resin and a polyfunctional acrylate.

[0066] Furthermore, for example, the functional layer (B) may contain a surface modifier, and the elements constituting the surface modifier may include silicon. Alternatively, the surface modifier may contain a silicon compound having a dimethylsiloxane skeleton. The surface modifier may be, for example, a leveling agent, a dimethylsiloxane-modified methacrylate ester, or a polydimethylsiloxane cyclic compound. Examples of the surface modifier include "LE-303" manufactured by Kyoeisha Chemical Co., Ltd. and "PC4100" manufactured by DIC Corporation. The amount of the surface modifier added is not particularly limited.

[0067] In the optical film of the present invention, the functional layer (B) is not particularly limited, but may be, for example, a hard coat layer as described above, or it may be an anti-glare hard coat layer.

[0068] The optical film of the present invention, for example, has a functional layer (B) formed using an anti-glare hard coat layer forming material containing a resin and a filler, and the functional layer (B) may have aggregated portions that form convex portions on the surface of the functional layer (B) due to the aggregation of the filler. Furthermore, in the aggregated portions that form the convex portions, the filler may be present in a state in which a plurality of them are clustered in one direction in the planar direction of the functional layer (B). In the image display device of the present invention, for example, the optical film of the present invention may be arranged such that the direction in which the plurality of fillers are clustered coincides with the direction of the long side of the black matrix pattern. Examples of the filler include the particles and the thixotropy imparting agent.

[0069] The functional layer (B) is formed, for example, by applying a coating solution containing a resin and a diluent solvent onto the surface of the light-transmitting substrate (A) to form a coating film, and then removing the solvent from the coating film, as described later. The resin can be, for example, a thermosetting resin or an ionizing radiation-curable resin that hardens with ultraviolet light or light. Commercially available thermosetting resins or UV-curable resins can also be used as the resin.

[0070] Examples of thermosetting resins and UV-curing resins include curable compounds having at least one of an acrylate group and a methacrylate group that hardens by heat, light (such as ultraviolet light), or electron beams. Examples include oligomers or prepolymers of polyfunctional compounds such as silicone resins, polyester resins, polyether resins, epoxy resins, urethane resins, alkyd resins, spiroacetal resins, polybutadiene resins, polythiol polyene resins, and polyhydric alcohols, such as acrylates or methacrylates. These may be used individually or in combination of two or more types.

[0071] The resin may also be a reactive diluent having at least one of an acrylate group and a methacrylate group. The reactive diluent may be, for example, the reactive diluent described in Japanese Patent Application Publication No. 2008-88309, and includes, for example, monofunctional acrylate, monofunctional methacrylate, polyfunctional acrylate, polyfunctional methacrylate, etc. As the reactive diluent, a trifunctional or more acrylate or a trifunctional or more methacrylate is preferred. This is because it can provide excellent hardness to the functional layer (B). Examples of the reactive diluent include butanediol glycerin ether diacrylate, isocyanuric acid acrylate, isocyanuric acid methacrylate, etc. These may be used individually or in combination of two or more.

[0072] As described above, the functional layer (B) may or may not contain a thixotropy-imparting agent. The thixotropy-imparting agent may be at least one selected from the group consisting of, for example, organic clay, oxidized polyolefin, and modified urea. The thixotropy-imparting agent may also be, for example, a thickening agent. The thixotropy-imparting agent may be used alone or in combination of two or more types.

[0073] In the optical film of the present invention, the thixotropy imparting agent may be present in an amount of, for example, 0.2 to 5% by mass or 0.4 to 4% by mass relative to the total mass of the resin forming the functional layer (B).

[0074] The optical film of the present invention may also have a configuration in which, for example, another layer (C) is laminated on the surface of the functional layer (B) opposite to the light-transmitting substrate (A). The other layer (C) may be attached to the functional layer (B) by, for example, an adhesive layer.

[0075] The other layer (C) is not particularly limited and may be, for example, a protective layer, a decorative layer, etc. The other layer (C) may be, for example, glass or a resin film (plastic film). The resin film is not particularly limited, but examples include the "E-MASK" series manufactured by Nitto Denko Corporation. The thickness of the other layer (C) is not particularly limited, but may be, for example, 10 μm or more, 20 μm or more, or 30 μm or more, or for example, 80 μm or less, 70 μm or less, 60 μm or less, 50 μm or less, or 40 μm or less.

[0076] The adhesive layer may be, for example, an adhesive layer formed of an adhesive (adhesive composition). In the present invention, the adhesive layer may be, for example, a layer that allows the other layer (C) to be re-peeled from the functional layer (B). The thickness of the adhesive layer is not particularly limited, but may be, for example, 5 μm or more, or 10 μm or more, or for example, 50 μm or less, 40 μm or less, 30 μm or less, or 20 μm or less. The adhesive is not particularly limited, but for example, a (meth)acrylic polymer may be used. These may be, for example, dissolved or dispersed in a solvent to form a solution or dispersion, which may be used as the adhesive (adhesive composition). Examples of the solvent include ethyl acetate, and one type may be used or multiple types may be used in combination. The concentration of the solute or dispersed phase (for example, the acrylic polymer) in the solution or dispersion may be, for example, 10% by mass or more, or 15% by mass or more, or for example, 60% by mass or less, 50% by mass or less, 40% by mass or less, or 25% by mass or less. In this invention, "(meth)acrylic polymer" refers to a polymer or copolymer of at least one monomer from (meth)acrylic acid, (meth)acrylic acid ester, and (meth)acrylamide. In this invention, (meth)acrylic acid means "at least one of acrylic acid and methacrylic acid," and "(meth)acrylic acid ester" means "at least one of acrylic acid ester and methacrylic acid ester." Examples of the (meth)acrylic acid ester include linear or branched alkyl esters of (meth)acrylic acid. In the linear or branched alkyl ester of (meth)acrylic acid, the number of carbon atoms in the alkyl group may be, for example, 1 or more, 2 or more, 3 or more, or 4 or more, and may be, for example, 18 or less, 16 or less, 14 or less, 12 or less, 10 or less, or 8 or less. The alkyl group may be substituted with or unsubstituted with one or more substituents. Examples of substituents include hydroxyl groups, and if there are multiple substituents, they may be the same or different. Examples of the (meth)acrylic acid ester include, for example, 2-ethylhexyl acrylate, 2-hydroxyethyl acrylate, and 4-hydroxybutyl acrylate.Furthermore, the adhesive may be of one type only, or multiple types may be used in combination.

[0077] Furthermore, the optical film of the present invention may or may not include any other layers besides the light-transmitting substrate (A), the functional layer (B), the adhesive layer, and the other layer (C). The other layer is not particularly limited, but examples include an easy-adhesion layer, an anti-reflective layer, and a substrate layer to which an adhesive is attached.

[0078] [2. Method for manufacturing optical films] The method for manufacturing the optical film of the present invention is not particularly limited and may be manufactured by any method, but the optical film can be manufactured, for example, as follows.

[0079] First, the functional layer (B) is formed on the light-transmitting substrate (A) (functional layer (B) formation step). This produces a laminate of the light-transmitting substrate (A) and the functional layer (B). The functional layer (B) formation step may include, for example, a coating step of applying the resin layer forming coating liquid (hereinafter sometimes simply referred to as "coating liquid" or "functional layer (B) forming material") onto the light-transmitting substrate (A), and a coating film forming step of drying the applied coating liquid to form a coating film. Alternatively, for example, the functional layer (B) formation step may further include a curing step of curing the coating film. The curing can be performed, for example, after the drying, but is not limited thereto. The curing can be performed, for example, by heating, light irradiation, etc. The light is not particularly limited, but may be, for example, ultraviolet light. The light source for the light irradiation is also not particularly limited, but may be, for example, a high-pressure mercury lamp.

[0080] The coating liquid (functional layer (B) forming material) may, for example, be a coating liquid containing the resin and the diluent (hereinafter sometimes simply referred to as "solvent") as described above. The coating liquid may or may not contain other components. The other components are not particularly limited, but examples include the particles and the thixotropy imparting agent.

[0081] The solvent is not particularly limited, and various solvents can be used. One type may be used alone, or two or more types may be used in combination. Depending on the composition of the resin, the type and content of the particles and the thixotropy imparter, the optimal type of solvent and solvent ratio may be appropriately selected to obtain the optical film of the present invention. The solvent is not particularly limited, but examples include alcohols such as methanol, ethanol, isopropyl alcohol (IPA), butanol, t-butyl alcohol (TBA), and 2-methoxyethanol; ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone, and cyclopentanone; esters such as methyl acetate, ethyl acetate, and butyl acetate; ethers such as diisopropyl ether and propylene glycol monomethyl ether; glycols such as ethylene glycol and propylene glycol; cellosolves such as ethyl cellosolve and butyl cellosolve; aliphatic hydrocarbons such as hexane, heptane, and octane; and aromatic hydrocarbons such as benzene, toluene, and xylene. Furthermore, for example, the solvent may include a hydrocarbon solvent and a ketone solvent. The hydrocarbon solvent may be, for example, an aromatic hydrocarbon. The aromatic hydrocarbon may be, for example, at least one selected from the group consisting of toluene, o-xylene, m-xylene, p-xylene, ethylbenzene, and benzene. The ketone solvent may be, for example, cyclopentanone and at least one selected from the group consisting of acetone, methyl ethyl ketone, methyl isobutyl ketone, diethyl ketone, cyclohexanone, isophorone, and acetophenone. The solvent preferably contains the hydrocarbon solvent (e.g., toluene) to dissolve a thixotropy imparting agent (e.g., a thickener). The solvent may be, for example, a mixture of the hydrocarbon solvent and the ketone solvent in a mass ratio of 90:10 to 10:90. The mass ratio of the hydrocarbon solvent to the ketone solvent may be, for example, 80:20 to 20:80, 70:30 to 30:70, or 40:60 to 60:40. In this case, for example, the hydrocarbon solvent may be toluene and the ketone solvent may be methyl ethyl ketone.Furthermore, the solvent may include, for example, toluene, and may also include at least one selected from the group consisting of ethyl acetate, butyl acetate, IPA, methyl isobutyl ketone, methyl ethyl ketone, methanol, ethanol, and TBA.

[0082] When an acrylic film is used as the light-transmitting substrate (A) to form an intermediate layer (permeable layer), a solvent suitable for the acrylic film (acrylic resin) can be preferably used. As such, the solvent may be, for example, a solvent containing a hydrocarbon solvent and a ketone solvent, as described above. The hydrocarbon solvent may be, for example, an aromatic hydrocarbon. The aromatic hydrocarbon may be, for example, at least one selected from the group consisting of toluene, o-xylene, m-xylene, p-xylene, ethylbenzene, and benzene. The ketone solvent may be, for example, at least one selected from the group consisting of cyclopentanone, acetone, methyl ethyl ketone, methyl isobutyl ketone, diethyl ketone, cyclohexanone, isophorone, and acetophenone. The solvent may be, for example, a solvent obtained by mixing the hydrocarbon solvent and the ketone solvent in a mass ratio of 90:10 to 10:90. The mass ratio of the hydrocarbon solvent to the ketone solvent may be, for example, 80:20 to 20:80, 70:30 to 30:70, or 40:60 to 60:40. In this case, for example, the hydrocarbon solvent may be toluene and the ketone solvent may be methyl ethyl ketone.

[0083] When triacetylcellulose (TAC), for example, is used as the light-permeable substrate (A), the solvent is not particularly limited, but examples include ethyl acetate, methyl ethyl ketone, MIBK (methyl isobutyl ketone), cyclopentanone, etc., and one type may be used or multiple types may be used in combination. In this case, the solvent may be, for example, a mixed solvent of MIBK and cyclopentanone. The mixing ratio of MIBK and cyclopentanone is not particularly limited, but for example, by mass ratio it may be 90:10 to 10:90, 80:20 to 20:80, or 70:30 to 30:70.

[0084] Furthermore, by appropriately selecting a solvent, the thixotropy properties of the anti-glare hard coat layer forming material (coating liquid) can be effectively expressed when a thixotropy imparting agent is included. For example, when using organic clay, toluene and xylene can be suitably used individually or in combination. For example, when using oxidized polyolefin, methyl ethyl ketone, ethyl acetate, and propylene glycol monomethyl methyl methyl ester can be suitably used individually or in combination. For example, when using modified urea, butyl acetate and methyl isobutyl ketone can be suitably used individually or in combination.

[0085] Various leveling agents can be added to the functional layer (B) forming material. For example, fluorine-based or silicone-based leveling agents can be used to prevent uneven coating (uniformity of the coated surface). Silicone-based leveling agents can also be used to include silicon as an element in the functional layer (B). In the present invention, a leveling agent can be appropriately selected depending on whether antifouling properties are required on the surface of the functional layer (B), or whether an anti-reflective layer (low refractive index layer) or a layer containing an interlayer filler is formed on the functional layer (B) as another layer (C).

[0086] The amount of the leveling agent added is, for example, 5 parts by weight or less, preferably in the range of 0.01 to 5 parts by weight, per 100 parts by weight of the resin.

[0087] The functional layer (B) forming material may, if necessary, contain pigments, fillers, dispersants, plasticizers, UV absorbers, surfactants, antifouling agents, antioxidants, etc., to the extent that it does not impair performance. These additives may be used individually or in combination of two or more types.

[0088] For the functional layer (B) forming material, for example, a conventionally known photopolymerization initiator, such as the one described in Japanese Patent Application Publication No. 2008-88309, can be used.

[0089] As a method for forming a coating film by coating the functional layer (B) forming material (coating liquid) onto the light-transmitting substrate (A), for example, coating methods such as the fountain coat method, die coat method, spray coat method, gravure coat method, roll coat method, and bar coat method can be used.

[0090] Next, as described above, the coating film is dried and cured to form the functional layer (B). The drying may be, for example, natural drying, air drying by blowing air on it, heat drying, or a combination of these methods.

[0091] The drying temperature of the functional layer (B) forming material (coating liquid) may be, for example, in the range of 30 to 200°C. The drying temperature may be, for example, 40°C or higher, 50°C or higher, 60°C or higher, 70°C or higher, 80°C or higher, 90°C or higher, or 100°C or higher, and may be 190°C or lower, 180°C or lower, 170°C or lower, 160°C or lower, 150°C or lower, 140°C or lower, 135°C or lower, 130°C or lower, 120°C or lower, or 110°C or lower. The drying time is not particularly limited, but may be, for example, 30 seconds or more, 40 seconds or more, 50 seconds or more, or 60 seconds or more, and may be 150 seconds or less, 130 seconds or less, 110 seconds or less, or 90 seconds or less.

[0092] The means for curing the coating film is not particularly limited, but ultraviolet curing is preferred. The irradiation dose of the energy source is 50 to 500 mJ / cm² as the integrated exposure dose at an ultraviolet wavelength of 365 nm. 2 This is preferable. The irradiation dose is 50 mJ / cm². 2 If the above conditions are met, hardening will proceed smoothly, and the hardness of the formed functional layer (B) will tend to be higher. Also, 500 mJ / cm 2 The following conditions can prevent discoloration of the formed functional layer (B).

[0093] As described above, a laminate of the light-transmitting substrate (A) and the functional layer (B) can be manufactured. This laminate may be used as is as the optical film of the present invention, or, for example, the other layer (C) may be attached to the surface of the functional layer (B) opposite to the light-transmitting substrate (A) using the adhesive layer to form the optical film of the present invention.

[0094] [3. Method for manufacturing an optical film winding and method for inspecting the quality of an optical film winding] Next, the method for manufacturing an optical film winding and the method for inspecting the quality of an optical film winding according to the present invention will be described in more detail with examples.

[0095] The method for manufacturing the optical film winding of the present invention includes, as described above, a winding step of winding an optical film to manufacture the optical film winding of the present invention, wherein the average value H of the plastic durometer hardness is measured at the outermost layer of the optical film winding. a The optical film is wound such that the plastic durometer hardness H1 at the center point satisfies the above formulas (1) and (2).

[0096] The winding process is not particularly limited, and for example, the average value H of the plastic durometer hardness a The method for manufacturing a wound optical film may be the same as a general method, except that the optical film is wound so that the plastic durometer hardness H1 at the center point satisfies formulas (1) and (2). Specifically, for example, the optical film of the present invention may be manufactured by continuously feeding out a long, light-transmitting substrate (A) and continuously forming the functional layer (B) and, if necessary, the adhesive layer, other layers (C), etc., while winding the optical film so that it satisfies formulas (1) and (2).

[0097] In addition, the method for manufacturing the optical film wound body of the present invention may include, for example, a quality inspection step of inspecting the manufactured optical film wound body by the quality inspection method of the optical film wound body of the present invention. As described above, the quality inspection method of the optical film wound body of the present invention is a quality inspection method of the optical film wound body. At the outermost surface layer of the optical film wound body, the average value H of the plastic durometer hardness a and the plastic durometer hardness H1 at the center point are confirmed by measurement whether they satisfy the above formulas (1) and (2). In the present invention, the method for measuring the plastic durometer hardness is not particularly limited as described above. For example, it can be measured by the measurement method defined in JIS K 6253. Note that the presence or absence of indentations on the optical film cannot be confirmed without unfolding and visually observing the optical film wound body. However, by measuring the plastic durometer hardness, if it is confirmed that the value of the formula (2) |(H a - H1)| is small, that is, the unevenness of the winding hardness is small, it can be inferred that there are few indentations on the optical film. In addition, the quality inspection method of the optical film wound body of the present invention may, for example, inspect whether the manufactured optical film wound body satisfies characteristics other than the above formulas (1) and (2). Specifically, for example, as described above, at the outermost surface layer of the optical film wound body, it may be confirmed by measurement whether the plastic durometer hardness and the thickness of the optical film at the measurement point of the plastic durometer hardness satisfy the relationship of the formula (4).

[0098] As described above, if the winding hardness (the pressure or tension applied to the optical film) of the optical film wound body varies greatly depending on the location and there is a large unevenness, for example, when foreign matter or the like is caught in a portion where the winding hardness is large (pressure is concentrated), there is a risk of generating indentations or scratches. On the other hand, if the winding hardness of the optical film wound body is loosened (the tension applied to the optical film is loosened) in an attempt to prevent the occurrence of indentations and scratches, defects (such as wrinkles) may occur in the optical film due to winding displacement, and there is a risk that the optical film cannot be supplied to the next process. The inventors of the present invention have repeatedly studied to solve this problem, and the average value H of the plastic durometer hardness a and the plastic durometer hardness H1 at the center point satisfy the above formulas (1) and (2). According to the present invention, as described above, even if the winding hardness is large and hard, an optical film wound body, an optical film, an optical member, an image display device, a method for manufacturing an optical film wound body, and a method for inspecting the quality of an optical film wound body in which the occurrence of scratches and indentations is suppressed or prevented can be provided.

[0099] Patent Document 1 also focuses on the durometer hardness of a wound body of a thermoplastic resin film. However, the invention described in Patent Document 1 is characterized in that the durometer hardness Hc at the center in the winding axis direction of the wound body and the durometer hardness He of at least a part within 30 mm from the end in the winding axis direction of the wound body satisfy Hc + 3 < He. That is, the invention described in Patent Document 1 is characterized in that the durometer hardness at the end in the winding axis direction of the wound body is greater than the durometer hardness at the center in the winding axis direction of the wound body. In other words, the invention described in Patent Document 1 does not require that the unevenness of the plastic durometer hardness in the width direction of the optical film wound body be small as in the formula (2) of the present invention. This is because in Patent Document 1, it is premised on winding a smooth film with a small surface roughness, and thus a high tension is not required to prevent winding displacement. In contrast, the inventors of the present invention reduce the unevenness of the plastic durometer hardness in the width direction of the optical film wound body as in the formula (2), and the average value H of the plastic durometer hardness as in the formula (1)a We found that the load is 40 N / m or more. As a result, the present invention can provide an optical film winding, an optical film, an optical component, an image display device, a method for manufacturing an optical film winding, and a method for inspecting the quality of an optical film winding, in which defects in the optical film due to winding misalignment (e.g., wrinkles) are suppressed or prevented even if the optical film has irregularities on its surface, and the occurrence of scratches and dents is suppressed or prevented. However, the optical film of the present invention is not limited to an optical film having irregularities on its surface, but may be a flat optical film without irregularities on its surface.

[0100] [4. Optical components and image display devices, etc.] The optical component of the present invention is not particularly limited, but may be, for example, a polarizing plate. The polarizing plate is also not particularly limited, but may include, for example, the optical film and polarizer of the present invention, or may further include other components. Each component of the polarizing plate may be bonded together, for example, with an adhesive or a bonding agent.

[0101] The image display device of the present invention is not particularly limited and any image display device may be used, but examples include liquid crystal display devices, organic EL display devices, and so on.

[0102] The image display device of the present invention is, for example, an image display device having the optical film of the present invention on its viewing surface, and the image display device may have a black matrix pattern.

[0103] The optical film of the present invention can, for example, be bonded to an optical component used in 11D via an adhesive or bonding agent on the light-transmitting substrate (A) side. In this bonding process, various surface treatments as described above may be applied to the surface of the light-transmitting substrate (A). As described above, the manufacturing method of the optical film of the present invention allows for flexible control of the surface shape of the optical film over a wide range. Therefore, the optical properties that can be obtained by laminating the optical film with other optical components using an adhesive or bonding agent cover a wide range corresponding to the surface shape of the optical film.

[0104] Examples of the optical components include polarizers or polarizing plates. Polarizing plates generally have a configuration in which a transparent protective film is provided on one or both sides of the polarizer. When transparent protective films are provided on both sides of the polarizer, the transparent protective films on the front and back may be made of the same material or different materials. Polarizing plates are usually placed on both sides of the liquid crystal cell. Furthermore, polarizing plates are arranged so that the absorption axes of the two polarizing plates are approximately perpendicular to each other.

[0105] The configuration of the polarizing plate formed by laminating the optical films is not particularly limited, but for example, it may be a configuration in which a transparent protective film, the polarizer, and the transparent protective film are laminated on the optical film in that order, or a configuration in which the polarizer and the transparent protective film are laminated on the optical film in that order.

[0106] The image display device of the present invention has the same configuration as conventional image display devices, except that the optical film is arranged in a specific direction. For example, in the case of an LCD, it can be manufactured by appropriately assembling various components such as liquid crystal cells, polarizing plates and other optical elements, and, if necessary, an illumination system (backlight, etc.), and incorporating a drive circuit.

[0107] The optical film of the present invention is not particularly limited in its applications and can be used for any purpose. Examples of such applications include office automation equipment such as personal computer monitors, laptops, and photocopiers; portable devices such as mobile phones, watches, digital cameras, personal digital assistants (PDAs), and portable game consoles; household electrical appliances such as video cameras, televisions, and microwave ovens; in-vehicle equipment such as backup monitors, car navigation system monitors, and car audio systems; display equipment such as information monitors for commercial stores; security equipment such as surveillance monitors; and nursing and medical equipment such as nursing monitors and medical monitors. [Examples]

[0108] Next, examples of the present invention will be described together with comparative examples. However, the present invention is not limited by the following examples and comparative examples.

[0109] In the following examples and comparative examples, the parts of substances are parts by mass (parts by weight) unless otherwise specified.

[0110] [Examples 1 - 7 and Comparative Examples 1 - 2] Optical film wound bodies of Examples 1 - 7 and Comparative Examples 1 - 2 were manufactured as follows. As the optical film used as the raw material for the optical film wound body, the following optical film was used in all of Examples 1 - 7 and Comparative Examples 1 - 2.

[0111] The optical film wound bodies of Examples 1 - 7 and Comparative Examples 1 - 2 were manufactured by variously changing the width W [m] and length L [m] of the optical film as shown in Table 1 below, and also variously changing the plastic durometer hardness as shown in Table 1 below. In Table 1 below, the "average value [Ha]" of the "wound body durometer hardness [H]" represents the average value H of the plastic durometer hardness in the above formula (1) or formula (4) a [N / m]. "|(H a - H1)| / H a ≤ 0.1" represents "|(H a - H1)| / H a in the above formula (2). W represents the width [m] of the optical film. The "plastic deformation amount" represents the plastic deformation amount [nm] when the optical film is indented by the nanoindentation method. The "elastic recovery rate" represents the elastic recovery rate [%] when the optical film is indented by the nanoindentation method. L represents the length [m] of the optical film. D represents the average value D a [μm] of the optical film thickness in the above formula (4). The "number of indentations" indicates how many indentations caused by foreign matter are present per 1 m when the entire surface of the optical film obtained by unfolding the optical film wound body is visually observed. Note that an optical film with 10 or fewer indentations per 1 m caused by foreign matter is determined to be a good product, and an optical film with more than 10 indentations per 1 m caused by foreign matter 2 is considered defective. 2 per 1 m is determined to be a good product, and an optical film with more than 10 indentations per 1 m caused by foreign matter 2More than 10 optical films were identified as defective.

[0112] The plastic durometer hardness was measured according to the method of JIS K 6253. The amount of winding misalignment of the optical film winding, the number of dents in the optical film, the amount of plastic deformation, the elastic deformation rate, and the thickness were measured according to the methods described below.

[0113] [Measurement of winding misalignment] This will be explained using Figure 4. A perpendicular line 100b was drawn to the winding shaft 100a at the position where the optical film constituting the optical film winding body 100 was furthest forward relative to the winding core 110 used for winding the optical film winding body 100. Conversely, a perpendicular line 100c was drawn to the winding shaft 100a at the position where the optical film was furthest backward relative to the winding core 110. The distance X from perpendicular line 100b to perpendicular line 100c was defined as the winding misalignment.

[0114] [Counting the number of dents in the optical film] The manufactured optical film windings are disassembled, and the optical film at the outermost layer (L0) and the optical film at the intermediate position in the winding count (L 1 / 2 ), the optical film (L) closest to the winding core, with a total area of ​​1 m² each. 2 It was collected in such a way that the total length was 3m. 2 The optical film was analyzed using a three-wavelength fluorescent lamp as the light source. The light source was positioned at a 45° angle to the film, and the number of dents was counted while reflecting the light off the film. The dents were judged as ×, △, or ○ according to the following criteria, and those judged as × were counted as the number of dents. The average of the counts (L0 + L0) was then calculated. 1 / 2 +L) / 3 = Number of indentations [pieces / m] in each example 2 The evaluation result was determined as follows. ×: Distortion of reflected light is visible. △: Slight distortion is visible, but within acceptable limits. ○: No distortion of reflected light is visible.

[0115] [Method for measuring the plastic durometer hardness of wound materials] The plastic durometer hardness was measured according to the method of JIS K 6253, as described above. The center point in the width direction opposite to the end of the winding of the optical film was defined as h1, and the plastic durometer hardness measured at h1 was defined as H1 [N / m]. The point in the width direction at a distance of 10 mm from one end was defined as h 21 to, h 21 The plastic durometer hardness measured with H 21 [N / m] was defined as the point at which the distance from one end in the width direction is W / 4. 11 to, h 11 The plastic durometer hardness measured with H 11 The value was set to [N / m]. The point in the width direction at a distance of 10 mm from the other end was defined as h 22 to, h 22 The plastic durometer hardness measured with H 22 [N / m] was defined as the point at which the distance from the other end in the width direction is W / 4. 12 to, h 12 The plastic durometer hardness measured with H 12 [N / m] was used. h1, h 21 h 11 h 22 h 12 Plastic durometer hardness H1, H at 5 points 21 H 11 H 22 H 12 The average value [N / m] is H a The value was set to [N / m], where W is the width [m] of the optical film at the point directly opposite the end of the winding end of the optical film winding body.

[0116] [Method for measuring plastic deformation and elastic deformation rate using a nanoindenter] The optical films of each example and comparative example, which served as the measurement samples, were cut into approximately 1 cm squares, fixed to a designated support in the apparatus described below, and nanoindentation measurements were performed. Device: Manufactured by HysitroN Inc., product name "TriboiNdeNter" Indenter used: BerkovicH (triangular pyramid type) Measurement method: Single indentation measurement Indentation depth: 500nm

[0117] When the indenter is pressed in under the above conditions, the maximum displacement (H max ) is measured, and then after unloading, the amount of plastic deformation (H F The following was measured: After indenting the indenter to a depth of 500 nm under the above conditions, the load was removed, and the distance from the sample plane after removal to the pressurized part at the tip of the indenter was measured. This distance was defined as the amount of plastic deformation. The obtained maximum displacement H max [nm] and plastic deformation amount H F The elastic recovery rate was calculated from [nm] according to the following formula.

[0118] Elastic recovery rate (%) = [(H max -H F ) / H max ]×100

[0119] [Examples 1-7, Comparative Examples 1-2] A hard coat layer forming material was manufactured as follows, a hard coat film (optical film) was manufactured using this material, and then an optical film winding body was manufactured by winding the hard coat film.

[0120] [Example 1] (Manufacturing of hard coat layer forming materials) As resins to be included in the hard coat layer forming material, 45 parts by weight of UV-curable urethane acrylate resin (manufactured by Shin-Nakamura Chemical Co., Ltd., trade name "UA53H-80MB", solids content 80%) and 55 parts by weight of polyfunctional acrylate mainly composed of pentaerythritol triacrylate (manufactured by Osaka Organic Chemical Industry Co., Ltd., trade name "Viscoat #300", solids content 100%) were prepared. For every 100 parts by weight of the resin solids content of the above resin, 3 parts by weight of a photopolymerization initiator (manufactured by BASF, trade name "OMNIRAD907") and 0.05 parts by weight of a leveling agent (manufactured by DIC Corporation, trade name "GRANDIC PC4100", solids content 10%) were mixed. This mixture was diluted with MIBK / butyl acetate mixed solvent (weight ratio 50 / 50) to a solids content concentration of 40% to produce a hard coat layer forming material (coating liquid, anti-glare hard coat layer (B) forming material).

[0121] (Manufacturing of hard coat films and optical film windings) As the light-transmitting substrate (A), a transparent plastic film substrate (acrylic film, manufactured by Toyo Kohan Co., Ltd., product name "HX40UF", thickness: 40 μm, film width: 1300 mm) was prepared. The anti-glare hard coat layer (B) forming material (coating liquid) was continuously applied to one side of the transparent plastic film substrate (light-transmitting substrate (A)) for 3000 m using a die coater to form an undried coating film (coating process). Then, the transparent plastic film substrate with this undried coating film was transported at a speed of 30 m / sec to the next drying process (coating film formation process). In the drying process (coating film formation process), the undried coating film was dried by heating at 100°C for 1 minute to form a coating film. After that, a high-pressure mercury lamp was used to apply an integrated light intensity of 300 mJ / cm². 2 The coating film was cured by irradiating it with ultraviolet light to form a hard coat layer with a maximum thickness of 6.0 μm, thereby giving the total film thickness 46 μm. A hard coat film (optical film) was manufactured in this manner.

[0122] Furthermore, the hard coat film (optical film) with the continuous coating completed was transported while being wound with a winding tension set to 200N to produce the desired optical film winding. When the plastic durometer hardness of the optical film winding produced in this way was measured, it was found to be H 21 =69N / m, H 11 =73N / m, H1=72N / m, H 12 = 72 N / m, H 22 The value was 76 N / m. That is, the representative (average) value was 72 N / m, and the variation was 1%. Furthermore, the plastic deformation of the manufactured hard coat film in sheet form was 75.9 μm, and the elastic recovery rate was 88.4%. Following the method described above, the amount of winding misalignment was checked and found to be 0 mm, and the number of indentations was counted to be 0 per meter. 2 These results are summarized in Table 1.

[0123] [Example 2] The hard coat layer forming material, hard coat film (optical film), and optical film winding were manufactured in the same manner as in Example 1, except that the resin contained in the hard coat layer forming material consisted of 40 parts by weight of UV-curable urethane acrylate resin (manufactured by Shin-Nakamura Chemical Co., Ltd., product name "UA53H-80MB", solids content 80%) and 60 parts by weight of polyfunctional acrylate mainly composed of pentaerythritol triacrylate (manufactured by Osaka Organic Chemical Industry Co., Ltd., product name "Viscoat #300", solids content 100%), and the film was wound up after continuous coating was completed with a winding tension setting of 230N. The plastic durometer hardness of the optical film winding manufactured in this manner was measured, and H 21 =76N / m, H 11 =78N / m, H1=74N / m, H 12 = 75 N / m, H 22The value was 77 N / m. That is, the representative (average) value was 76 N / m, and the variation was 3%. Furthermore, the plastic deformation of the manufactured hard coat film in sheet form was 79.5 μm, and the elastic recovery rate was 85.4%. Following the method described above, the amount of winding misalignment was checked and found to be 0 mm, and the number of indentations was counted at 1 indentation / m. 2 These results are summarized in Table 1.

[0124] [Example 3] The hard coat layer forming material, hard coat film (optical film), and optical film winding were manufactured in the same manner as in Example 1, except that the resin contained in the hard coat layer forming material consisted of 30 parts by weight of UV-curable urethane acrylate resin (manufactured by Shin-Nakamura Chemical Co., Ltd., product name "UA53H-80MB", solids content 80%) and 70 parts by weight of polyfunctional acrylate mainly composed of pentaerythritol triacrylate (manufactured by Osaka Organic Chemical Industry Co., Ltd., product name "Viscoat #300", solids content 100%), and the film was wound up after continuous coating was completed with a winding tension set to 200N. The plastic durometer hardness of the optical film winding manufactured in this manner was measured, and H 21 =65N / m, H 11 =68N / m, H1=73N / m, H 12 = 71 N / m, H 22 The value was 70 N / m. That is, the representative (average) value was 69 N / m, and the variation was 5%. Furthermore, the plastic deformation of the manufactured hard coat film in sheet form was 86.2 μm, and the elastic recovery rate was 78.4%. Following the method described above, the amount of winding misalignment was checked and found to be 0 mm, and the number of indentations was counted at 3 per meter. 2 These results are summarized in Table 1.

[0125] [Example 4] As a light-transmitting substrate (A), a transparent plastic film substrate (acrylic film, manufactured by Toyo Kohan Co., Ltd., product name "HX40UF", thickness: 40 μm, film width: 300 mm) was prepared, and the anti-glare hard coat layer (B) forming material (coating liquid) was continuously applied (coated) for 6500 m using a die coater, and the tension during winding was set to 60 N, the hard coat layer forming material, hard coat film (optical film), and optical film winding were manufactured in the same manner as described in Example 2. When the plastic durometer hardness of the optical film winding manufactured in this manner was measured, H 21 = 74 N / m, H 11 =68N / m, H1=72N / m, H 12 = 75 N / m, H 22 The value was 69 N / m. Therefore, the representative (average) value was 72 N / m, and the variation was 5%. Following the method described above, the amount of winding misalignment was found to be 2 mm, and the number of indentations was counted at 1 per meter. 2 These results are summarized in Table 1.

[0126] [Example 5] As a light-transmitting substrate (A), a transparent plastic film substrate (acrylic film, manufactured by Toyo Kohan Co., Ltd., product name "HX40UF", thickness: 40 μm, film width: 2500 mm) was prepared, and the anti-glare hard coat layer (B) forming material (coating liquid) was applied continuously for 50 m using a die coater, and the tension during winding was set to 400 N. Except for these differences, the hard coat layer forming material, hard coat film (optical film), and optical film winding were manufactured in the same manner as described in Example 2. The plastic durometer hardness of the optical film winding thus manufactured was measured, and H 21 = 77 N / m, H 11 =78N / m, H1=78N / m, H 12 = 80 N / m, H 22 The value was 79 N / m. That is, the representative (average) value was 78 N / m, and the variation was 1%. Following the method described above, the amount of winding misalignment was checked and found to be 0 mm, and the number of indentations was counted to be 0 per meter. 2These results are summarized in Table 1.

[0127] [Example 6] A transparent plastic film substrate (PET film, manufactured by Toray Industries, Inc., product name "Lumirror", thickness: 188 μm, film width: 1300 mm) was prepared as the light-transmitting substrate (A), and the anti-glare hard coat layer (B) forming material (coating liquid) was continuously applied (coated) for 2000 m using a die coater, and the tension during winding was set to 400 N. Except for these differences, the hard coat layer forming material, hard coat film (optical film), and optical film winding were manufactured in the same manner as described in Example 2. The plastic durometer hardness of the optical film winding thus manufactured was measured, and H 21 = 44 N / m, H 11 =47N / m, H1=43N / m, H 12 = 44 N / m, H 22 The value was 48 N / m. That is, the representative (average) value was 45 N / m, and the variation was 5%. Following the method described above, the amount of winding misalignment was found to be 4 mm, and the number of indentations was counted to be 0 per meter. 2 These results are summarized in Table 1.

[0128] [Example 7] As a light-transmitting substrate (A), a transparent plastic film substrate (COP film, manufactured by Nippon Zeon Co., Ltd., product name "ZF series", thickness: 13 μm, film width: 1300 mm) was prepared, and the anti-glare hard coat layer (B) forming material (coating liquid) was continuously applied (coated) for 3000 m using a die coater, and the tension during winding was set to 200 N, the hard coat layer forming material, hard coat film (optical film), and optical film winding were manufactured in the same manner as described in Example 2. When the plastic durometer hardness of the optical film winding manufactured in this manner was measured, H 21 = 87 N / m, H 11 =88N / m, H1=91N / m, H 12 = 94 N / m, H 22The value was 89 N / m. That is, the representative (average) value was 90 N / m, and the variation was 1%. Following the method described above, the amount of winding misalignment was checked and found to be 0 mm, and the number of indentations was counted at 3 per meter. 2 These results are summarized in Table 1.

[0129] [Comparative Example 1] Except for winding the film after continuous coating was completed with a winding tension set to 70N, the hard coat layer forming material, hard coat film (optical film), and optical film winding were manufactured in the same manner as in Example 1. When the plastic durometer hardness of the optical film winding manufactured in this manner was measured, H 21 = 31 N / m, H 11 =28N / m, H1=29N / m, H 12 =32N / m, H 22 The value was 28 N / m. Therefore, the representative (average) value was 30 N / m, and the variation was 2%. Following the method described above, the amount of winding misalignment was found to be 10 mm, and the number of indentations was counted to be 0 per meter. 2 These results are summarized in Table 1.

[0130] [Comparative Example 2] Except for setting the winding tension to 300N and performing continuous coating at a speed of 10m / min, a hard coat layer forming material, a hard coat film (optical film), and an optical film winding were manufactured in the same manner as in Example 1. When the plastic durometer hardness of the optical film winding manufactured in this manner was measured, H 21 = 72 N / m, H 11 =58N / m, H1=58N / m, H 12 =65N / m, H 22 The value was 72 N / m. That is, the representative (average) value was 65 N / m, and the variation was approximately 11%. Following the method described above, the amount of winding misalignment was checked and found to be 0 mm, and the number of indentations was counted at 40 per meter. 2 These results are summarized in Table 1.

[0131] [Table 1]

[0132] As shown in Table 1 above, the optical film windings of Examples 1 to 7 all had extremely small winding misalignment and very few dents caused by foreign matter. In contrast, Comparative Example 1 had an average value H of the plastic durometer hardness in formula (1) above. a The [N / m] was 30 N / m (i.e., less than 40 N / m), meaning the winding was loose, and as a result, the winding misalignment was larger compared to the example. In addition, in Comparative Example 2, |(H in formula (2) above a -H1)| / H a Approximately 11% (i.e., 0.11, exceeding 0.1) showed a large variation in plastic durometer hardness, resulting in a significantly higher number of foreign matter-induced dents compared to the examples. [Industrial applicability]

[0133] As described above, the present invention provides an optical film winding, an optical film, an optical component, an image display device, a method for manufacturing an optical film winding, and a method for inspecting the quality of an optical film winding, in which scratches and dents are suppressed or prevented even if the winding hardness is high and hard. The present invention is particularly suitable for optical films having irregularities on their surface, but is not limited to these and can be applied to any optical film. Therefore, the optical component, image display device, etc. of the present invention are not particularly limited and can be applied to any optical component, image display device, etc. [Explanation of Symbols]

[0134] 10 Optical film 11 Light-transparent base material (A) 12 Functional Layer (B) 12a Functional layer forming resin 12b particle 12c Thixotropic agent 100 Optical film windings 100A Position of the end of the winding at the outermost layer of the winding body 100 100B The position of the winding end 100 at the outermost surface of the winding body 100, directly opposite to the winding end 100A. 100a winding shaft 100b, 100c Perpendicular to the winding axis 100a 110 core h1, h 11 h 12 h 21 h 22 Measurement points for hardness of plastic durometer H1, H 11 H 12 H 21 H 22 Plastic durometer hardness

Claims

1. A winding of optical film, In the outermost layer of the aforementioned optical film winding, the average value of the plastic durometer hardness H ａ The plastic durometer hardness H at the center point １ An optical film winding body characterized in that it satisfies the following formulas (1) and (2). H ａ ≧40 (1) 0≦|(H ａ -H １ )| / H ａ ≦0.1 (2) In the above formulas (1) and (2), H １ This is the plastic durometer hardness [N / m] at the center point in the width direction on the outermost layer of the optical film winding, directly opposite the end of the winding of the optical film winding, H ａ This is the average value [N / m] of the plastic durometer hardness at five points in the width direction opposite to the end of the winding of the optical film: a point at a distance of 10 mm from one end, a point at a distance of W / 4 from the one end, the center point, a point at a distance of W / 4 from the other end, and a point at a distance of 10 mm from the other end. However, W is the width [m] of the optical film opposite to the end of the winding of the optical film.

2. The optical film winding according to claim 1, wherein the optical film is an optical film whose plastic deformation when pressed by a nanoindentation method is 85 Nm or less and whose elastic recovery rate is 80% or more.

3. The optical film winding body according to claim 1 or 2, wherein the relationship between the width and length of the optical film satisfies the following formula (3). 40 ≤ L / W ≤ 20000 (3) In the above formula (3), W is the width [m] of the optical film, L is the length [m] of the optical film.

4. The optical film winding body according to any one of claims 1 to 3, wherein the plastic durometer hardness and the thickness of the optical film at the measurement point of the plastic durometer hardness satisfy the following formula (4). 0.25≦H ａ / D ａ ≦7 (4) In the above formula (4), H ａ This is the average value [N / m] of the plastic durometer hardness at five points in the width direction opposite to the end of the winding of the optical film: a point 10 mm from one end, a point 1 W / 4 from the one end, the center point, a point 1 W / 4 from the other end, and a point 10 mm from the other end. However, W is the width [m] of the optical film opposite to the end of the winding of the optical film. D ａ This is the average value [μm] of the optical film thickness at the five points which are the measurement points for the plastic durometer hardness.

5. The optical film winding body according to any one of claims 1 to 4, wherein the optical film is an optical film having irregularities on its surface.

6. The optical film winding body according to any one of claims 1 to 5, wherein the optical film is an anti-glare film.

7. The optical film winding body according to any one of claims 1 to 6, wherein the optical film is a hard coat film.

8. The optical film winding body according to any one of claims 1 to 7, wherein the optical film is an anti-glare hard coat film.

9. An optical film obtained by unwinding the optical film winding described in any one of claims 1 to 8.

10. An optical component comprising the optical film described in claim 9.

11. The optical component according to claim 10, which is a polarizing plate.

12. An image display device comprising the optical film according to claim 9, or the optical member according to claim 10 or 11.

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