TW201910821A - Laminated body and method of manufacturing the same - Google Patents

Abstract

The provided is a laminated body and a method for producing the same having a uniform light diffusing property among the different points in a film. The present invention relates to a laminated body and the like, wherein an over film is laminated on at least one side of a light diffusion control film, and there is an internal region having a plurality of regions having a relatively high refractive index in a region having a relatively low refractive index, when a direction perpendicular to the coating transfer direction of a composition for the light diffusion control film is defined as length direction and a direction traverse to the coating direction is defined as a short direction, and the maximum value of the phase difference Re (nm) measured along the short direction of the over film Is set to Remax and the minimum value is set to Remin, a following relational equation (1) is satisfied. (Remax-Remin)/(Remax+Remin) x 100 < 35 (%) (1).

Description

Laminated body and manufacturing method of laminated body

[0001] The present invention relates to a laminate and a method for producing the laminate. In particular, the laminated body of the light-diffusion control film and the overlying laminated film obtained by photo-hardening in a state in which a coating layer made of a composition for a light-diffusion control film is laminated with the overlying laminated film is light diffusion. The light-diffusion characteristics of the control film are uniform laminates regardless of the locations within the surface of the film, and a method for manufacturing such laminates.

[0002] Conventionally, in the field of optical technology, such as a liquid crystal display device or a projection screen, it has been proposed to use a light diffusion control film. The light-diffusion control film has the following light-diffusion characteristics: it shows a certain light-diffusion state in a specific incident angle range (hereinafter sometimes referred to as "light-diffusion incident angle area"), and an incident angle deviating from the light-diffusion incident angle area The range allows the incident light to pass directly, or displays a light diffusion state different from the light diffusion state in the light diffusion incident angle region. [0003] As such light diffusion control films, various aspects are known. In particular, they have been widely used in film structures having a plurality of pillars having relatively high refractive indexes in a region having a relatively low refractive index. Light diffusion control film. [0004] In addition, as other types of light diffusion control films, light diffusing films having a louver structure in which a plurality of plate-shaped regions having different refractive indexes with different refractive indexes are arranged in the film in any direction along the film surface have been widely used. [0005] However, it is known that a light diffusion control film having such a pillar structure or a louver structure is formed by coating a film with a composition for a light diffusion control film containing two or more polymerizable compounds having different refractive indices. The coating layer is obtained by irradiating active energy rays by a specific method. That is, by irradiating the coating layer with a specific active energy ray controlled in the direction of travel, the coating layer is hardened while phase-separating two or more polymerizable compounds to obtain a light diffusion control film having a specific internal structure. . [0006] However, when the coating layer is directly irradiated with a specific active energy ray, it is difficult to see the entire thickness direction of the film, that is, until a specific internal structure is formed on the film. That is, although a specific internal structure can be formed in a portion below the film thickness direction, a problem that an area in which the internal structure is not formed occurs in the upper portion is seen. Therefore, a technique is disclosed in which a specific internal structure is not formed on a thin film without a region where an internal structure is not formed (for example, refer to Patent Document 1). [0007] That is, Patent Document 1 discloses a method for manufacturing an anisotropic optical film whose diffusivity changes according to the incident angle of light, which is characterized by including the following steps: a photocurable uncured resin composition layer On one side, a light irradiation mask joining step for joining a light irradiation mask having a turbidity value of 1.0 to 50.0%, and after the light irradiation mask joining step, the uncured resin is composed by transmitting light through the light irradiation mask. A hardening step in which the material layer is hardened to form an anisotropic diffusion layer. It is also described that the surface roughness of the light irradiation mask is 0.05 to 0.50 μm, or the oxygen transmission coefficient of the light irradiation mask is 1.0 × 10 ^-11 cm ³ (STP) cm / (cm ² .s.Pa) or less. . That is, the coating layer formed of the composition for a light diffusion control film is subjected to photohardening in a state where a specific overlying laminated film is laminated, and the occurrence of a region where no internal structure is formed is suppressed. [Prior Art Document] [Patent Document] [0008] [Patent Document 1] Japanese Patent Application Publication No. 2016-194687 (Scope of Patent Application)

[Problems to be Solved by the Invention] [0009] However, even in the case of using a light irradiation mask described in Patent Document 1, it is difficult to stably suppress the occurrence of a region where an internal structure is not formed. In particular, in a continuous light-diffusion control film having a certain width, a part where a region where an internal structure is not formed does not occur, and a part where the occurrence occurs are also seen. As a result, the light diffusion characteristics in the film surface also change depending on the incident position of the light, and the problem of uneven light diffusion characteristics is seen in the entirety. [0010] Therefore, the present inventors, after actively working in view of the above, found that by setting the deviation of the phase difference measured in a specific direction in the plane of the overlying laminated film to a value within a specific range, The present invention is completed when no area where no internal structure is formed, or even if it occurs, the internal structure can be uniformly formed. That is, an object of the present invention is to provide a light diffusion control film and an overlying laminated film obtained by light curing in a state in which a coating layer made of a composition for a light diffusion control film is laminated with the overlying laminated film. The laminated body is a light-diffusion control film having uniform light-diffusion characteristics regardless of the location within the surface of the film, and a method for manufacturing such a laminated body. [Means for Solving the Problems] [0011] According to the present invention, the above-mentioned problems can be solved by providing a laminated body characterized by at least a light diffusion control film derived from a composition for a light diffusion control film. A laminated body in a state where an overlying laminated film is laminated on one side, and the light diffusion control film has an internal structure having a plurality of high refractive index regions in a low refractive index region and the high refractive index region extends in a thickness direction, and is a layer In the laminated surface of the composite, the moving direction when forming the light diffusion control film is set to the long side direction, the direction perpendicular to the long side direction is set to the short side direction, and the short side direction of the overlying laminated film is to be set. When the maximum value of the measured phase difference Re (nm) is set to Re _max and the minimum value is set to Re _min , the following relational expression (1) is satisfied, (Re _max -Re _min ) / (Re _max + Re _min ) × 100 <35 (%) (1). That is, according to the laminated body of the present invention, since the deviation of the phase difference Re measured along a specific direction in the surface of the overlying laminated film is set to a value within a specific range, the composition for a film for controlling a film by light diffusion is used. The formed coating layer is hardened in a state where the overlying laminated film is laminated, and a laminated body of the light diffusion control film and the overlying laminated film with uniform light diffusion characteristics regardless of the location within the film surface can be obtained. [0012] In forming the laminate of the present invention, the length in the short-side direction of the overlying laminate film is preferably a value in the range of 100 to 10,000 mm. With such a configuration, a laminate having a sufficient length in the short-side direction can be obtained, and a light diffusion control film having a sufficient length in the short-side direction can be obtained. [0013] In the case where the laminated body of the present invention is configured, the central value of the phase difference Re of the overlying laminated film is preferably a value in the range of 1000 to 3000 nm. With such a configuration, it is possible to effectively suppress occurrence of a region in the light diffusion control film in which an internal structure is not formed. [0014] When forming the laminate of the present invention, the film thickness of the overlying laminated film is preferably a value in a range of 5 to 5000 μm. With such a configuration, the overlying laminated film that satisfies the relationship (1) can be obtained in a stable manner. [0015] In the case where the laminate of the present invention is configured, the internal structure of the light diffusion control film is preferably contained in a region having a relatively low refractive index, and a plurality of columns having a relatively high refractive index are formed in the film thickness direction. Structure made of objects. With this configuration, a light diffusion control film having isotropic light diffusion characteristics can be obtained. [0016] In the case where the laminated body of the present invention is configured, the internal structure of the light diffusion control film preferably includes a shutter structure in which a plurality of plate-shaped regions having different refractive indexes are alternately arranged along any direction of the film surface. With this configuration, a light diffusion control film having anisotropic light diffusion characteristics can be obtained. [0017] Another aspect of the present invention is a method for manufacturing a laminate, which is characterized by the method for manufacturing a laminate described above, and includes the following steps (a) to (d). (B) a step of coating the composition for a light diffusion control film in the form of a thin film to form a coating layer; Step, (c) the step of laminating the exposed surface of the coating layer to satisfy the lamination film on the relational expression (1), (d) moving the coating layer through the overlying lamination film, The step of irradiating the cloth layer with active energy rays. That is, according to the method for manufacturing a laminated body of the present invention, the deviation of the phase difference Re measured along a specific direction in the surface of the overlying laminated film is set to a value within a specific range. Therefore, in a state where the overlying laminated film is laminated on the coating layer formed of the composition for a light diffusion control film, it is hardened (photocured) by irradiating active energy rays. As a result, it is possible to obtain a laminated body of a light diffusion control film and an overlying laminated film that are uniform in terms of light diffusion characteristics regardless of the location within the film surface.

[First Embodiment] As shown in FIG. 1 (a), a first embodiment of the present invention is such that a cover layer is laminated on at least one side of a light diffusion control film 10 derived from a composition for a light diffusion control film. The laminated body 100 in the state of the laminated film 4. Further, the light diffusion control film 10 has an internal structure 20 having a plurality of high-refractive-index regions 12 in the low-refractive-index region 14 and the high-refractive-index region 12 extending in the thickness direction, and is a laminate 100 In the lamination plane, the moving direction when the light diffusion control film 10 is formed is set to the long side direction, the direction perpendicular to the long side direction is set to the short side direction, and the length along the short side of the overlying laminated film 4 is set. When the maximum value of the phase difference Re (nm) measured in the lateral direction is set to Re _max and the minimum value is set to Re _min , the following relational expression (1) is satisfied, (Re _max -Re _min ) / (Re _max + Re _min ) × 100 <35 (%) (1). [0020] That is, the laminated body 100 has the following characteristics: the laminated body 100 in a state where the laminated film 4 is laminated on at least one side of the light diffusion control film 10, and the light diffusion control film 10 includes a high refractive index The hardened component (high refractive index active energy ray hardened component) and the low refractive index hardened component (low refractive index active energy ray hardened component) are composed of a cured product of a composition for a light diffusion control film. Further, the light diffusion control film as a hardened material has an internal structure 20 including a plurality of regions 12 having a relatively high refractive index in a region 14 having a relatively low refractive index, and as shown in FIG. 1 (b), The direction of movement MD of the coating layer 1 derived from the coating layer 1 of the composition for a light diffusion control film during light curing is set to the longitudinal direction LD, and it will be in the lamination plane of the laminate 100 and in the longitudinal direction LD. The vertical direction is set to the short-side direction SD, and the maximum value of the phase difference Re (nm) measured along the short-side direction SD of the overlying laminated film 4 is set to Re _max and the minimum value is set to Re _min , which satisfies the above. Relationship (1). Hereinafter, a first embodiment of the present invention will be specifically described with reference to appropriate drawings. However, the composition for a light diffusion control film and its hardened state will be described in the second embodiment. [0021] 1. Overlay Laminated Film The overlaminated film of the present invention is shown in FIG. 1 (b), which is applied when the coating layer 1 derived from the composition for a light diffusion control film is light cured. The moving direction MD of layer 1 is set to the long-side direction LD, the direction of lamination within the laminate plane and perpendicular to the long-side direction LD is set to the short-side direction SD, and the short-side direction SD of the overlying laminated film 4 is set When the maximum value of the measured phase difference Re (nm) is set to Re _max and the minimum value is set to Re _min , the following relational expression (1) is satisfied. (Re _max -Re _min ) / (Re _max + Re _min ) × 100 <35 (%) (1) The reason is that if the deviation value of the phase difference Re shown on the left side of the relationship (1) is 35% The above values cause the internal structure of the light diffusion control film obtained by photocuring through the overlying laminated film to be excessively changed depending on the location within the film surface. Therefore, it is difficult to maintain the uniformity of the light diffusion characteristics in the film plane. That is, the upper limit value of the deviation value of the phase difference Re shown on the left side of the relational expression (1) is more preferably set to a value of 30% or less, more preferably set to a value of 25% or less, and more specifically set to 10% or less. Value. In addition, the smaller the deviation value of the phase difference Re shown on the left side of the relational expression (1), the better, but if it is too small, the material selection range is excessively limited. Therefore, the lower limit of the deviation value of the phase difference Re shown on the left side of the relational expression (1) is preferably a value of 0.1% or more, more preferably a value of 0.5% or more, and still more preferably a value of 1% or more. When calculating the deviation of the retardation Re, it is preferable to measure the retardation Re at equally spaced positions from 5 to 100 along the short-side direction SD of the overlying laminated film (the same applies to the central value of the retardation Re described later). In addition, as is clear from FIG. 1 (b), the long-side direction LD and short-side direction SD of the overlying laminated film are consistent with the long-side direction LD and short-side direction SD of the laminate, and also the light diffusion constituting the laminate. The long-side direction LD and the short-side direction SD of the control film and the step sheet are the same. The phase difference Re can be adjusted by stretching the film, and is particularly preferably adjusted by biaxial stretching. [0023] Here, the relationship between the deviation of the phase difference Re of the overlying laminated film and the uniformity of the light diffusion characteristics of the light diffusion control film will be briefly described. That is, it is considered that there is a close relationship between the vibration direction of the irradiated active energy rays and the refractive index distribution structure formed. In addition, when the active energy ray is irradiated to the overlying laminated film, the vibration in the long-side direction LD and the short-side direction SD of the overlying laminated film is affected differently according to the phase difference of the overlying laminated film. Therefore, it is presumed that the divergence caused changes the vibration direction of the active energy ray. As a result, it is presumed that the light diffusion characteristics of the light diffusion control film formed under the overlying laminated film is approximately controlled by the phase difference Re of the overlying laminated film. Therefore, it is considered that when the phase difference Re deviates from the short-side direction SD, the light diffusion characteristics also deviate correspondingly. [0024] The median value of the phase difference Re of the overlying laminated film is preferably a value in the range of 1000 to 3000 nm. The reason is that if the median value of the retardation Re is less than 1000 nm, the material may be difficult to select because it is a thin film with an excessively low retardation Re. On the other hand, if the central value of the phase difference Re exceeds 3,000 nm, it may be difficult to select a material because it is a thin film with an excessively high phase difference Re. Therefore, the lower limit of the median value of the phase difference Re is more preferably a value of 1100 nm or more, and more preferably a value of 1200 nm or more. The upper limit of the median value of the phase difference Re is more preferably a value of 2800 nm or less, and even more preferably a value of 2900 nm or less. [0025] The arithmetic mean roughness (Ra) of the surface of the active energy ray-irradiated side of the overlying laminated film is preferably a value in a range of 1 to 200 nm. If the Ra value is less than 1 nm, when the overlying laminate film is rolled out, the films may adhere to each other, and vibration during peeling may increase. Therefore, the vibration may be transmitted to the active energy ray irradiated portion, and the formation accuracy of the internal structure of the light diffusion control film may be reduced. On the other hand, if this Ra has a value exceeding 200 nm, the surface shape is too large, and therefore the active energy rays may be diffused to prevent the formation of the structure. Therefore, the lower limit of the arithmetic average roughness (Ra) of the overlying laminated film is more preferably a value of 5 nm or more, and more preferably a value of 10 nm or more. In addition, the upper limit of the arithmetic mean roughness (Ra) of the overlying laminated film is preferably a value of 100 nm or less, more preferably a value of 40 nm or less, and particularly preferably 30 nm or less. The arithmetic mean roughness (Ra), which is one of the surface roughnesses, can be measured in accordance with JIS B 0601: 2001, or can be measured in accordance with ANSI B46.1. [0026] The maximum ridge (Rp) of the overlying laminated film is preferably a value in a range of 20 to 5000 nm. The reason is that if the Rp value is less than 20 nm, when the overlying laminate film is rolled out, the films may adhere to each other and vibrations during peeling may increase. Therefore, the vibration may be transmitted to the active energy ray irradiated portion, and the internal structure formation accuracy of the light diffusion control film may be reduced. On the other hand, if the Rp exceeds a value of more than 5000 nm, the surface shape is too large, which may cause diffusion of the active energy rays and hinder the formation of the structure. Therefore, the lower limit of the maximum ridge (Rp) of the overlying laminated film is more preferably a value of 50 nm or more, more preferably a value of 100 nm or more, and particularly preferably 300 nm or more. In addition, the upper limit of the maximum ridge (Rp) of the overlying laminated film is preferably a value of 2000 nm or less, more preferably a value of 1000 nm or less, and particularly preferably 600 nm or less. The maximum ridge (Rp), which is one of the surface roughness, can be measured in accordance with JIS B 0601: 2001, or it can be measured according to ANSI B46.1. [0027] The turbidity of the overlying laminated film is preferably a value in a range of 1 to 25%. The reason is that if the turbidity is less than 1%, when the overlying laminated film is rolled out, the films may adhere to each other and the vibration during peeling may increase. Therefore, the vibration may be transmitted to the active energy ray irradiated portion, and the internal structure formation accuracy of the light diffusion control film may be reduced. On the other hand, if the turbidity exceeds a value of 25%, the surface shape is too large, which may cause diffusion of the active energy rays and hinder the formation of the structure. Therefore, the lower limit of the turbidity of the overlying laminated film is more preferably a value of 3% or more, and more preferably a value of 5% or more. The upper limit of the turbidity of the overlying laminated film is more preferably a value of 20% or less, and even more preferably a value of 15% or less. [0028] The total light transmittance of the overlying laminated film is preferably a value in a range of 70 to 97%. The reason is that if the total light transmittance is less than 70%, the transmittance of the active energy ray is too low, and it may be difficult to efficiently form a specific internal structure in the light diffusion control film. On the other hand, if the total light transmittance exceeds a value of 97%, the material selection range may be too limited. Therefore, the lower limit of the total light transmittance of the overlying laminated film is more preferably a value of 75% or more, and more preferably a value of 80% or more. In addition, the upper limit of the total light transmittance of the overlying laminated film is more preferably a value of 95% or less, and even more preferably a value of 93% or less. [0029] In addition, the material used as the overlying laminated film is not particularly limited, but examples include polyethylene terephthalate film, triethyl cellulose film, cyclic olefin polymer film, cyclic olefin film, Ionic polymer film, polyethylene film, polyvinyl chloride film, polyvinylidene chloride film, polyvinyl alcohol film, polypropylene film, polyester film, polycarbonate film, polystyrene film, polyacrylonitrile film, ethylene acetic acid The vinyl ester copolymer film, ethylene-vinyl alcohol copolymer film, ethylene-methacrylic acid copolymer film, nylon film, and cellophane can be used alone or in combination of two or more. The reason is that if these materials are used, a laminated film satisfying the relational expression (1) can be obtained more stably. [0030] The length in the short-side direction of the overlying laminated film is preferably a value in a range of 100 to 10,000 mm. The reason is that when the length in the short-side direction is less than 100 mm, the length in the short-side direction of the light diffusion control film constituting the laminate also becomes less than 100 mm, and the light-diffusion control film does not satisfy the practical requirements. Case of required size. On the other hand, when the length in the short side direction exceeds a value of 10,000 mm, it may be difficult to uniformly irradiate the active energy rays in the width direction. Therefore, the lower limit of the length in the short-side direction of the overlying laminated film is more preferably a value of 200 mm or more, more preferably a value of 300 mm or more, and particularly preferably a value of 600 mm or more. In addition, the upper limit value of the length in the short-side direction of the overlying laminated film is more preferably a value of 8000 mm or less, still more preferably a value of 6000 mm or less, and particularly preferably a value of 3000 mm or less. [0031] The film thickness of the overlying laminated film is preferably a value in a range of 5 to 5000 μm. The reason is that when the film thickness is less than 5 μm, handling becomes difficult, and wrinkles may occur when the overlaminate film is bonded. On the other hand, when the film thickness exceeds a value of 5000 μm, handling becomes difficult, and wrinkles may occur when the overlaminate film is transferred. Therefore, the lower limit of the film thickness of the overlying laminated film is more preferably a value of 10 μm or more, and more preferably a value of 30 μm or more. The upper limit of the film thickness of the overlying laminated film is more preferably a value of 1000 μm or less, still more preferably a value of 400 μm or less, and even more preferably a value of 100 μm or less. In addition, on both surfaces of the overlying laminate film, a surface on the side in contact with the light diffusion control film may be coated with a release agent such as silicone resin to provide a release layer. [0032] 2. Light diffusion control film (1) Basic principle of light diffusion of light diffusion control film Initially, as an example of the light diffusion control film of the present invention, the use of FIGS. The isotropic light diffusion control film 10a having isotropic light diffusion characteristics will be described. First, FIG. 2 (a) shows a top view of an isotropic light diffusion control film 10a having a pillar structure 20a in the film, and FIG. 2 (b) shows a vertical cut along the dotted line AA and the like shown in FIG. 2 (a) A cross-sectional view of the isotropic light diffusion control film 10a when the cut surface is viewed from the direction of the arrow. Fig. 3 (a) shows an overall view of an isotropic light diffusion control film 10a having a pillar structure 20a in the film, and Fig. 3 (b) shows an isotropic light diffusion control film 10a shown in Fig. 3 (a). The degree of diffusion of the diffused light (the expanded shape of the diffused light). As shown in the top view of FIG. 2 (a), the isotropic light diffusion control film 10a has a pillar structure 20a formed of a pillar 12a having a relatively high refractive index and a region 14a having a relatively low refractive index. As shown in the cross-sectional view of FIG. 2 (b), inside the isotropic light diffusion control film 10a, there are pillars 12a having a relatively high refractive index and regions 14a having a relatively low refractive index. The relatively high rate of the pillars 12a are arranged in a standing state so as to have a certain interval. [0033] It is thus estimated that as shown in FIG. 3 (a), the incident light in the region where the incident angle θ1 is a light diffusion incident angle is diffused by the isotropic light diffusion control film 10a. That is, as shown in FIG. 2 (b), the incident angle of the incident light to the isotropic light diffusion control film 10a is a value parallel to a specific angle range from the boundary surface 20a 'of the pillar structure 20a, that is, Is the value in the area of the incident angle of light diffusion. The incident light (52, 54) passes through the inside of the pillar 12a with a relatively high refractive index in the pillar structure 20a along the film thickness direction while changing the direction, so that the light exit side The direction of light travel is different. As a result, it is estimated that when the incident angle is within the light diffusion incident angle region, the incident light is diffused by the isotropic light diffusion control film 10a to become specific diffused light (52 ', 54'). On the other hand, when the incident angle of the incident light to the isotropic light diffusion control film 10a deviates from the light diffusion incident angle region, it is estimated as shown in FIG. 2 (b), and the incident light 56 does not pass through the isotropic light. The diffusion control film 10a diffuses and passes directly, and becomes transmitted light 56 '. [0034] Based on the above basic principle, the isotropic light diffusion control film 10a having the pillar structure 20a, for example, as shown in FIG. 3 (a), may exhibit the dependence of the incident angle on the transmission and diffusion of light. Moreover, as shown in FIG. 2 (b), the isotropic light diffusion control film 10a provided with the pillar structure 20a generally has "isotropic property" as its light diffusion characteristic. Herein, the "isotropic" in the present invention means that as shown in FIG. 3 (b), when incident light is diffused through a thin film, the diffused outgoing light is in a plane parallel to the thin film (sometimes referred to as a top view) ), A property that the degree of diffusion of the light does not change due to the direction in the plane. More specifically, as shown in FIG. 3 (a), when the incident light is diffused by the isotropic light diffusion control film 10a, the diffusion degree of the emitted light becomes circular in a plane parallel to the film. [0035] In addition, as shown in FIG. 3 (a), when the incident light angle θ1 of the isotropic light diffusion control film is included in the light diffusion incident angle region, even if the incident angle θ1 is different, it is on the light exit surface. The side can also perform light diffusion in substantially the same manner. Therefore, an isotropic light-diffusion control film can be said to have a light-concentrating effect of concentrating light on a specific portion. In addition, it is considered that the direction of incident light inside the columnar object 12a in the column structure is changed to a step-exponential type in which the direction changes in a linear zigzag manner by total reflection as shown in FIG. 2 (b). There are also cases where the gradient index type changes in a curve shape. [0036] The internal structure of the light diffusion control film of the present invention is not limited to the above-mentioned pillar structure as long as the internal structure includes a high refractive index region and a low refractive index region. That is, in the technical field of the light diffusion control film, if it has an internal structure that can be formed by phase separation known in the past, it can also be formed in the light diffusion control film of the present invention. For example, as shown in FIG. 4 (a), the shutter structure 20b may be a louver structure 20b having a plurality of plate-like regions (12b, 14b) having different refractive indices alternately arranged along the film surface in any one direction. Alternatively, as shown in FIG. 4 (b), the columnar object may have a curved column structure 20c having a curved portion 16 at an intermediate point in the film thickness direction. Alternatively, as shown in FIG. 4 (c), in a region 14d having a relatively low refractive index, a plurality of thin sheet objects 12d having a relatively high refractive index are arranged along a film surface in a plurality of rows in a specific internal structure. 20d. Alternatively, as shown in FIG. 4 (d), the blind structure 20b and the pillar structure 20a may be combined. That is, the types of internal structures known in the technical field of light diffusion control films continue to be diverse, but the light diffusion control film of the present invention may be any of these internal structures. [0037] Moreover, the basic principle of light diffusion is the same as in the case of the pillar structure 20a, regardless of the internal structure. However, due to the shape of each internal structure, the shape of the diffused light is different. For example, in the case of the louver structure 20b shown in FIG. 4 (a), a rod-shaped diffused light is generated in a plan view of the anisotropic light diffusion, and when the curved column structure 20c shown in FIG. 4 (b) is above the curved portion Part of the light diffused by the isotropic light is generated below the bent portion, and the diffused light is diffused by the isotropic light. In addition, when the specific internal structure 20d shown in FIG. 4 (c) is a hybrid type of the blind structure 20b and the column structure 20a, diffused light with an oval shape in a plan view is generated, as shown in FIG. 4 (d). In the case of 20b and the pillar structure 20a, a part of the light diffused by the pillar structure 20a is further diffused by the light in the louver structure 20b, so that bullet-like diffused light is generated when viewed from above. [0038] (2) Internal structure The internal structure in the light diffusion control film of the present invention is not particularly limited as long as it includes a high refractive index region and a low refractive index region to obtain light diffusion characteristics, and may be a pillar structure or Various aspects of shutter structure. The pillar structure is described below as an example, but other internal structures such as the shutter structure may also be based on the contents of the pillar structure. [0039] As shown in FIGS. 2 (a) to 2 (b), the pillar structure 20a is an internal structure for isotropically diffusing incident light. Specifically, the pillar structure 20a is located in a relatively low refractive index area, and has a large amount of refraction. An internal structure with a relatively high rate of multiple pillars. [0040] (2) The refractive index difference between the relatively low refractive index region in the refractive index column structure and the relatively high refractive index of the plurality of pillars is preferably a value of 0.01 or more. The reason is that if the refractive index difference becomes a value of 0.01 or more, the angular region of total reflection of incident light in the column structure becomes narrow, so that the incident angle dependency may be excessively reduced. Therefore, the lower limit of the refractive index difference is more preferably a value of 0.03 or more, and more preferably a value of 0.1 or more. In addition, although this difference in refractive index is large and good, from the viewpoint of selecting a material that can form a pillar structure, about 0.3 is considered to be the upper limit. [0041] (2) -2 Maximum diameter. In the pillar structure 20a shown in FIGS. 2 (a) to (b), the maximum diameter in the cross section of the pillar is preferably within a range of 0.1 to 15 μm. value. The reason is that if the maximum diameter is less than 0.1 μm, it may be difficult to display the light diffusion characteristics in spite of the incident angle of incident light. On the other hand, if the maximum diameter exceeds a value of 15 μm, the amount of light traveling straight in the column structure may increase, which may reduce the uniformity of the diffused light. Therefore, in the column structure, the lower limit of the maximum diameter is more preferably a value of 0.5 μm or more, and more preferably a value of 1 μm or more. In the column structure, the upper limit of the maximum diameter is more preferably a value of 10 μm or less, and even more preferably a value of 5 μm or less. The cross-sectional shape of the pillar is not particularly limited, but is preferably, for example, a circle, an ellipse, a polygon, or an irregular shape. The cross-section of the pillar means a cross-section obtained by cutting a plane parallel to the film surface. The maximum diameter, length, and the like of the pillars can be measured by observation with an optical digital microscope. The same applies to the distance between the pillars in the numerical range of the maximum diameter. (2) -3 Thickness The thickness (length in the film thickness direction) of the pillar structure 20a shown in FIG. 2 (b) is preferably a value in the range of 10 to 700 μm. The reason is that if the thickness is less than 10 μm, incident light that goes straight in the column structure increases, and it may be difficult to obtain a range of sufficient light diffusion characteristics. On the other hand, if the thickness is more than 700 μm, when the composition for a light diffusion control film is irradiated with active energy rays to form a pillar structure, the pillar structure formed initially may diffuse the direction of photopolymerization, making it difficult to diffuse. The reason for the formation of the desired pillar structure. Therefore, the lower limit of the thickness of the pillar structure is more preferably a value of 30 μm or more, and more preferably a value of 50 μm or more. The upper limit of the thickness of the pillar structure is more preferably a value of 200 μm or less, and even more preferably a value of 100 μm or less. The "range of light diffusion characteristics" means the range of the incident angle showing the light diffusion characteristics and the expanded range of the diffused light. (2) -4 Inclination angle As shown in FIG. 2 (b), in the pillar structure 20a, the pillars 12a and the like preferably stand at a certain inclined angle with respect to the film thickness direction of the light diffusion control film. The reason is that by making the inclination angle of the pillars constant and reflecting the incident light more stably within the pillar structure, the dependency of the incident angle from the pillar structure can be further improved. More specifically, in the column structure, the inclination angle of the column with respect to the normal of the film surface is preferably a value in a range of 0 to 80 °. The reason is that if the inclination angle exceeds 80 °, the absolute value of the incident angle accompanying this active energy ray will also increase, so the reflection ratio of the active energy ray at the interface between the air and the coating layer will increase. When forming a pillar structure, there may be a case where an active energy ray having a higher illuminance must be irradiated. Therefore, the upper limit of the inclination angle is more preferably a value of 60 ° or less, and even more preferably a value of 40 ° or less. In addition, the inclination angle means the normal to the film surface and the columnar shape measured in the cross section when the film is cut by cutting the entire column into two surfaces along the axis perpendicular to the film surface. The angle of the narrower side of the angle formed by the uppermost part of the object. (3) Film thickness The film thickness of the light diffusion control thin film of the present invention is preferably a value in a range of 10 to 700 μm. The reason is that if the film thickness of the light diffusion control film is less than 10 μm, incident light that goes straight in the column structure may increase, and it may be difficult to display specific light diffusion characteristics. On the other hand, if the film thickness of the light diffusion control film exceeds 700 μm, when the composition for a light diffusion control film is irradiated with active energy rays to form a column structure, the initially formed column structure will cause the direction of photopolymerization to proceed. Diffusion, and it may be difficult to form a desired pillar structure. In addition, when applied to a display or the like, wrinkles may be easily generated in the displayed image. Therefore, the lower limit of the film thickness of the light diffusion control film is more preferably a value of 30 μm or more, and more preferably a value of 50 μm or more. The upper limit of the thickness of the light diffusion control film is more preferably a value of 300 μm or less, and even more preferably a value of 100 μm or less. (4) Characteristics Further, regarding the characteristics of the light diffusion control film of the present invention, it is preferable that the amplitude of the incident angle region with a turbidity of 70% or more is at a value of 60 ° or more. By limiting the amplitude of a specific incident angle region in this way, since the incident light can be efficiently captured and uniformly diffused, the brightness of the diffused light may be increased. Therefore, the width of the incident angle region with a turbidity of 70% or more is preferably set to a value of 80 ° or more, and more preferably set to a value of 100 ° or more. [0046] In addition, regarding the characteristics of the light diffusion control film of the present invention, the normal direction of the film surface is set to 0 °, and the incident light from a region of incidence angle is incident in a direction deviating from the region, when the incident light is inclined at 60 °, The central value of the transmitted light intensity PT is preferably set to a value in the range of 0.1 to 99%. The reason is that if the median value is less than 0.1%, the transmittance of the entire film may deteriorate. On the other hand, when the median value exceeds 99%, the incident angle region may be insufficient. Therefore, the lower limit of the median value is more preferably set to 1% or more, and more preferably 5% or more. The upper limit of the median value is more preferably 50% or less, and even more preferably 15% or less. In addition, the so-called straight-through transmitted light intensity is the percentage of the intensity of the outgoing light emitted from the same angle as the incident light divided by the intensity of the entire incident light. [0047] Regarding the characteristics of the light-diffusion control film of the present invention, the deviation of the linearly transmitted light intensity PT is preferably set to a value in the range of 0.1 to 3.8%. The reason is that if the deviation is less than 0.1%, it may be difficult to control. On the other hand, when the deviation is set to a value exceeding 3.8%, the light diffusion state may be darkened. Therefore, the lower limit of the deviation is more preferably 1% or more, and more preferably 2% or more. The upper limit of the deviation is more preferably 3.5% or less, and even more preferably 2.8% or less. [0048] 3. Step sheet As shown in FIG. 1 (a), the laminated body 100 of the present invention may also be on one side of the light diffusion control film 10, that is, the side opposite to the side on which the laminated film 4 is laminated On the surface, the step sheet 2 is laminated. In this way, by covering the two sides of the light diffusion control film with the above laminated film and the step sheet, the light diffusion control film can be effectively protected. Here, the so-called step sheet is a sheet to which a composition for a light diffusion control film is applied when a laminate is produced. As the sheet in this step, a common release film can be used, and examples thereof include polyester films such as polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, and the like. Polyolefin films such as polyethylene and polyethylene are coated with a release agent such as silicone resin to provide a release layer. The film thickness of the sheet in this step is usually preferably a value in the range of 20 to 150 μm. [Second Embodiment] A method for producing a laminated body according to an embodiment of the present invention is a method for producing a laminated body according to the first embodiment, which is characterized by including the following steps (a) to (d). (a) a step of preparing a composition for a light diffusion control film containing a high refractive index active energy ray hardening component and a low refractive index active energy ray hardening component; (b) coating the composition for a light diffusion control film in a thin film step; And the step of forming the coating layer, (c) the step of laminating the exposed surface of the coating layer to satisfy the relational expression (1) to cover the laminated film, (d) while moving the coating layer, passing through the upper coating layer The step of closing the thin film and irradiating the coating layer with active energy rays. Hereinafter, the second embodiment of the present invention will be specifically described with reference to appropriate drawings, focusing on differences from the first embodiment. [0050] 1. Step (a): Step of preparing a composition for a light diffusion control film Step (a) is a step of preparing a specific composition for a light diffusion control film. More specifically, it is a step of mixing the components (A) to (B) described below and other components as necessary. In addition, it is possible to directly stir at room temperature during mixing, but from the viewpoint of improving uniformity, it is preferable to stir under a heating condition of, for example, 40 to 80 ° C. to obtain a homogeneous mixed solution. Further, in order to obtain a desired viscosity suitable for coating, it is also preferable to further add a diluent solvent. (1) (A) component: high refractive index active energy ray hardening component A feature of the composition for a light diffusion control film of the present invention includes a high refractive index hardening component (high refractive index active energy ray hardening component) as ( A) ingredients. The reason is that by including a high refractive index active energy ray hardening component as the component (A), and the low refractive index hardening component (low refractive index active energy ray hardening component) described later as the component (B), the polymerization rate is between A specific difference is generated, and the two components are prevented from being uniformly copolymerized with each other, whereby the component (A) and the component (B) can be hardened while being phase-separated. Thereby, although it is a uniform composition at the stage before hardening, it is possible to form a specific internal structure of a column structure or a shutter structure during hardening, so that the light diffusion control film as the obtained hardened material can be efficiently used. Excellent light diffusion characteristics for incident light diffusion. (1) The refractive index of the high refractive index active energy ray-hardened component having a refractive index of (A) -1 is preferably a value in a range of 1.5 to 1.65. The reason is that if the refractive index of the component (A) is less than 1.5, the refractive index difference with the low-refractive-index active energy ray-hardened component as the component (B) becomes too small, making it difficult to obtain effective light diffusion characteristics. The reason. On the other hand, if the refractive index of the component (A) exceeds 1.65, the refractive index difference between the component (B) and the component (B) becomes large, but it is also difficult to form an appearance compatible with the component (B). The reason. Therefore, the lower limit of the refractive index of the (A) component is more preferably a value of 1.55 or more, and more preferably a value of 1.56 or more. The upper limit of the refractive index of the (A) component is more preferably a value of 1.6 or less, and even more preferably a value of 1.59 or less. The refractive index of the component (A) means the refractive index of the component (A) before curing by light irradiation. The refractive index can be measured in accordance with JIS K0062: 1992, for example. [0053] (1) -2 Kinds of (A) component types are not particularly limited, but (meth) acrylic acid esters containing plural aromatic rings are preferred. The reason is that if these compounds are used, it is possible to perform light hardening while phase-separating the component (A) and the component (B) more efficiently, and to obtain more excellent light diffusion characteristics. Examples of these compounds include, for example, biphenyl (meth) acrylate, naphthyl (meth) acrylate, anthracene (meth) acrylate, benzylphenyl (meth) acrylate, and biphenyl (meth) acrylate Phenoxyalkyl ester, naphthyloxyalkyl (meth) acrylate, anthryloxyalkyl (meth) acrylate, benzylphenoxyalkyl (meth) acrylate, o-phenoxy (meth) acrylate Benzyl ester, m-phenoxy benzyl (meth) acrylate, p-phenoxy benzyl (meth) acrylate, etc., or a part of these by halogen, alkyl, alkoxy, halogenated alkyl And so on. The "(meth) acrylic acid" means both acrylic acid and methacrylic acid. [0054] As the component (A), a compound containing a biphenyl ring is more preferable, and a biphenyl compound represented by the following general formula (1) is more preferable. [0055] (In the general formula (1), R ¹ to R ¹⁰ are each independently, at least one of R ¹ to R ¹⁰ is a substituent represented by the following general formula (2), and the rest are a hydrogen atom, a hydroxyl group, and a carboxyl group. , Alkyl, alkoxy, halogenated alkyl, hydroxyalkyl, carboxyalkyl, and any of the halogen atom substituents). [0057] (In the general formula (2), R ¹¹ is a hydrogen atom or a methyl group, the carbon number n is an integer of 1 to 4, and the repeating number m is an integer of 1 to 10). [0059] The reason is presumed that by including a biphenyl compound having a specific structure as the (A) component, a specific difference may occur in the polymerization speed of the (A) component and the (B) component, and the (A) component and the (B) The compatibility of the components is reduced to a specific range, and the copolymerizability of the two components can be reduced. In addition, by increasing the refractive index of a region having a relatively high refractive index derived from the component (A), it is easier to adjust the difference from the refractive index of a region having a relatively low refractive index originating from the (B) component to a value greater than a specific value. . [0060] As specific examples of the biphenyl compound represented by the general formula (1), compounds represented by the following formulae (3) to (4) can be preferably exemplified. [0061] [0062] (2) Component (B): Low-refractive index active energy ray hardening component The composition for a light diffusion control film of the present invention includes a low-refractive index active energy ray hardening component as the (B) component. The reason is that by including a low refractive index active energy ray hardening component as the (B) component and a specific difference in polymerization rate between the high refractive index active energy ray hardening component and the high refractive index active energy ray hardening component described above as the (A) component, the two are suppressed Since the components are uniformly copolymerized with each other, the components (A) and (B) can be effectively light-cured while being phase-separated. Thereby, although it is a uniform composition at the stage before light hardening, a specific internal structure of a column structure or a shutter structure can also be formed during light hardening, so that the light diffusion control film as the obtained hardened material can be given a good efficiency. Excellent light diffusion characteristics to diffuse incident light. (2) The refractive index of the low-refractive-index active energy ray-hardened component whose refractive index is (B) component is preferably a value in the range of 1.4 to 1.5. The reason is that if the refractive index of the component (B) is less than 1.4, the refractive index difference between the component (A) and the component (A) becomes large, but the compatibility with the component (A) is extremely deteriorated, making it difficult to form a specific internal structure. The reason for the construction. On the other hand, if the refractive index of the component (B) exceeds 1.5, the difference in refractive index between the component (A) and the component (A) becomes too small, and it may be difficult to obtain desired light diffusion characteristics. Therefore, the lower limit of the refractive index of the component (B) is more preferably a value of 1.45 or more, and more preferably a value of 1.45 or more. The upper limit of the refractive index of the (B) component is more preferably a value of 1.49 or less, and even more preferably a value of 1.48 or less. The refractive index of the component (B) means the refractive index of the component (B) before curing by light irradiation. The refractive index can be measured in accordance with JIS K0062: 1992 as described above. [0065] The difference between the refractive index of the component (A) and the refractive index of the component (B) is preferably set to a value of 0.01 or more. The reason is that if the difference in refractive index is less than 0.01, the angle of total reflection of incident light in a specific internal structure becomes narrow, so that the range of light diffusion characteristics may become excessively narrow. On the other hand, if this refractive index difference becomes an excessively large value, the compatibility between the (A) component and the (B) component is excessively deteriorated, and it may be difficult to form a specific internal structure. Therefore, the lower limit value of the difference between the refractive index of the (A) component and the refractive index of the (B) component is more preferably a value of 0.05 or more, and more preferably a value of 0.1 or more. The upper limit of the difference between the refractive index of the (A) component and the refractive index of the (B) component is more preferably a value of 0.5 or less, and even more preferably a value of 0.2 or less. In addition, the refractive index of (A) component and (B) component here means the refractive index of (A) component and (B) component before hardening by light irradiation. (2) The type of (2) -2 and the type of (B) component are not particularly limited, but examples thereof include a urethane (meth) acrylate and a group having a (meth) acrylfluorenyl group in a side chain. A (meth) acrylic polymer, a (meth) acrylfluorene-containing silicone resin, an unsaturated polyester resin, and the like are particularly preferably a urethane (meth) acrylate. The reason is that if it is a urethane (meth) acrylate, the component (A) and component (B) can be more effectively light-cured while being phase-separated, and more excellent light diffusion characteristics can be obtained. The reason. The (meth) acrylate means both acrylate and methacrylate. [0067] The urethane (meth) acrylate is (B1) a compound containing at least two isocyanate groups, (B2) a polyol compound, preferably a diol compound, and particularly preferably a polyalkylene diene. Alcohol and (B3) hydroxyalkyl (meth) acrylate. In addition, the component (B) is an oligomer that also includes a repeating unit having a urethane bond. The compound containing at least two isocyanate groups as the component (B1) may be exemplified by 2,4-toluene diisocyanate, 2,6-toluene diisocyanate, 1,3-xylene diisocyanate, and 1,4-xylene. Diisocyanates, aromatic isocyanates such as 4,4'-diisocyanuric acid methylene diphenyl (MDI), aliphatic polyisocyanates such as hexamethylene diisocyanate, isophorone diisocyanate (IPDI), hydrogenated diisocyanates Alicyclic polyisocyanates such as phenylmethane diisocyanate, etc., and these ureton bodies, isocyanurate bodies, and further ethylene glycol, propylene glycol, neopentyl glycol, trimethylolpropane, castor oil, etc. Adducts of reactants of low molecular weight active hydrogen-containing compounds (for example, xylene diisocyanate trifunctional adducts) and the like. [0068] Among the components that form the urethane (meth) acrylate, the polyalkylene glycol as the (B2) component is exemplified by polyethylene glycol, polypropylene glycol, polybutylene glycol, and polyhexamethylene glycol. Alcohols and the like are particularly preferably polypropylene glycol. The reason is that if it is polypropylene glycol, when the component (B) is cured, it can be a good soft segment in the cured product, and the rationality or mountability of the obtained light diffusion control film can be effectively improved. The weight average molecular weight of the component (B) can be adjusted mainly by the weight average molecular weight of the component (B2). Here, the weight average molecular weight of the component (B2) is usually 2300 to 19500, preferably 4300 to 14300, and particularly preferably 6300 to 12300. [0069] Among the components that form the urethane (meth) acrylate, the hydroxyalkyl (meth) acrylate as the (B3) component is exemplified by 2-hydroxyethyl (meth) acrylate, ( 2-hydroxypropyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, 3-hydroxybutyl (meth) acrylate, 4- (meth) acrylate 4- Hydroxybutyl esters, etc. In addition, based on the viewpoint that the polymerization rate of the urethane (meth) acrylate obtained is lowered and a specific internal structure is formed more effectively, hydroxyalkyl methacrylate is particularly preferable, and 2-methyl methacrylate is more preferable. Hydroxyethyl ester. (2) -3 blending amount When the total amount of (A) component and (B) component is 100 parts by weight, the blending ratio of (A) component and (B) component ((A) (Component; (B) component (weight ratio)) is preferably set to a value within a range of 20:80 to 80:20. That is, when the total amount of the (A) component and the (B) component is 100 parts by weight, the blending ratio of the (B) component is preferably a value within a range of 20 to 80 parts by mass. The reason is that if the blending ratio of the (B) component is less than 20 parts by weight, the width of the region where the refractive index derived from the (A) component is relatively high and the refractive index derived from the (B) component is relatively low. In comparison, the region width is excessively large, and it may be difficult to obtain good light diffusion characteristics. On the other hand, if the blending ratio of the (B) component exceeds 80 parts by weight, the proportion of the (A) component relative to the (B) component will decrease, and the refractive index derived from the (A) component will be relatively high. Compared with the region width where the refractive index derived from the component (B) is relatively low, the range width of Zn is excessively small, and it may be difficult to obtain good light diffusion characteristics. Therefore, when the total amount of the (A) component and the (B) component is set to 100 parts by weight, the lower limit value of the blending ratio of the (B) component is more preferably set to a value of 40 parts by mass or more, and more preferably. The value is 55 mass parts or more. When the total amount of the (A) component and the (B) component is 100 parts by weight, the upper limit value of the blending ratio of the (B) component is more preferably set to a value of 70 parts by mass or less, and more preferably The value is set to 65 parts by mass or less. (3) Component (C): Photopolymerization initiator. In the composition for a light diffusion control film, a photopolymerization initiator is preferably contained as the component (C). The reason is that by containing a photopolymerization initiator, when the composition for a light diffusion control film is irradiated with an active energy ray, the component (A) and the component (B) can be more effectively photocured while being phase separated, and This is because more excellent light diffusion characteristics can be obtained. [0072] Here, examples of the photopolymerization initiator include benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin n-butyl ether, and benzoin isobutyl ether. , Acetophenone, dimethylaminoacetophenone, 2,2-dimethoxy-2-phenylacetophenone, 2,2-diethoxy-2-phenylacetophenone, 2-hydroxy 2-methyl-1-phenylpropane-1-one, 1-hydroxycyclohexylphenyl ketone, 2-methyl-1- [4- (methylthio) phenyl] -2-morpholinyl- Propane-1-one, 4- (2-hydroxyethoxy) phenyl-2- (hydroxy-2-propyl) one, benzophenone, p-phenylbenzophenone, 4,4-dione Ethylaminobenzophenone, dichlorobenzophenone, 2-methylanthraquinone, 2-ethylanthraquinone, 2-tert-butylanthraquinone, 2-aminoanthraquinone, 2-methylthiazine Tonketone, 2-ethylthioxanthone, 2-chlorothioxanthone, 2,4-dimethylthioxanthone, 2,4-diethylthioxanthone, benzyldimethylacetal, phenethyl Ketodimethylacetal, p-dimethylaminobenzoate, oligo [2-hydroxy-2-methyl-1- [4- (1-methylvinyl) phenyl] propane], etc., One of these may be used alone, or two or more of them may be used in combination. [0073] The blending amount of the photopolymerization initiator as the component (C) is preferably within a range of 0.2 to 20 parts by mass relative to 100 parts by mass of the total amount of the components (A) and (B). value. The reason is that if the blending amount of the component (C) is less than 0.2 parts by weight, the polymerization initiation point is lacking, and therefore it may be difficult to sufficiently harden the composition for a light diffusion control film. On the other hand, if the blending amount of the component (C) is more than 20 parts by weight, yellowing of the light diffusion control film or reduction in durability may occur. Therefore, the lower limit of the blending amount of the component (C) is more preferably a value of 0.5 parts by weight or more, and even more preferably a value of 1 part by weight or more. In addition, the upper limit of the blending amount of the component (C) is more preferably a value of 15 parts by weight or less, and even more preferably a value of 10 parts by weight or less. [0074] (4) Other additives As long as the effect of the present invention is not impaired, other additives may be appropriately blended. Examples of the other additives include antioxidants, antistatic agents, polymerization accelerators, polymerization inhibitors, infrared absorbers, ultraviolet absorbers, plasticizers, diluents, and leveling agents. The content of other additives is generally set to a value in the range of 0.01 to 5 parts by weight based on 100 parts by weight of the total amount of the components (A) and (B). [0075] Furthermore, it is particularly preferable to incorporate an ultraviolet absorber as another additive. The reason is that when an active energy ray is irradiated by mixing an ultraviolet absorber, the active energy ray of a specific wavelength can be selectively absorbed within a specific range. As a result, the hardening of the composition for a light diffusion control film is not inhibited, but a specific internal structure formed inside the obtained light diffusion control film may have a bent portion as shown in FIG. 4 (b), for example. [0076] The ultraviolet absorber is preferably a free hydroxyphenyltriazine-based ultraviolet absorber, a benzotriazole-based ultraviolet absorber, a benzophenone-based ultraviolet absorber, and a hydroxybenzoate-based ultraviolet absorber. At least one selected from the group. The reason is that if these ultraviolet absorbers are used, bending can be more clearly generated in a specific internal structure, so that the range of light diffusion characteristics in the obtained light diffusion control film can be more effectively expanded. That is, if the ultraviolet absorber having a peak at a wavelength closer to the wavelength of 365 nm of the main wavelength of the high-pressure mercury lamp is used, it can be confirmed that the bending occurs even with a small blending amount. [0077] The blending amount of the ultraviolet absorber in the composition for a light diffusion control film is preferably less than 2 parts by weight based on 100 parts by weight of the total amount of the components (A) and (B). (Except 0 parts by weight). The reason is that if the blending amount of the ultraviolet absorber is 2 parts by weight or more, the curing of the composition for a light diffusion control film may be hindered, shrinkage wrinkles may be generated on the film surface, or the film may not be completely cured. On the other hand, when the blending amount of the ultraviolet absorber is excessively small, it may be difficult to sufficiently bend the internal structure formed inside the light diffusion control film. Therefore, the lower limit of the blending amount of the ultraviolet absorber is more preferably 0.01 part by weight or more and 0.02 part by weight or more relative to 100 parts by weight of the total amount of the component (A) and the component (B). value. The upper limit of the amount of the ultraviolet absorber is more preferably 1.5 parts by weight or less and still more preferably 1 part by weight or less based on 100 parts by weight of the total amount of the (A) component and the (B) component. value. [0078] 2. Step (b): As shown in FIG. 5 (a), the coating step (b) is a step of coating the composition for a light diffusion control film on the step sheet 2 with a film to form a coating layer 1. . As this step, a general release film can be used as described in the first embodiment. [0079] As a method for applying the composition for a light diffusion control film to the step sheet, for example, a bar coating method, a doctor blade coating method, a roll coating method, a blade coating method, and a die coating method can be used. Method, gravure coating method, and the like. The thickness of the coating layer at this time is preferably set to a value in the range of 10 to 700 μm. [0080] 3. Step (c): The laminating step, step (c), as shown in FIG. 5 (b), laminates the exposed surface of the coating layer 1 with a laminated film 4 satisfying the relationship (1). The steps. That is, it is a step of laminating in a manner that the gap between the step sheet 2 and the overlying laminated film 4 is maintained without pressing the coating layer 1 before curing. [0081] Step (d): The step (d) of the active energy ray irradiation step is shown in FIG. 5 (c). While moving the coating layer 1, the coating layer 1 is transmitted through the overlying laminated film 4, and the coating is applied. The layer 1 is irradiated with the active energy rays of the parallel light 60 to form a specific internal structure such as a column structure or a shutter structure in the film, thereby forming a light diffusion control film 10. Hereinafter, a case where a pillar structure is formed will be described as an example. [0082] That is, as shown in FIG. 5 (c), the coating layer 1 formed on the step sheet 2 is irradiated with parallel light 60 having high parallelism of light rays. Here, the term “parallel light” means a light that is slightly parallel and does not expand when viewed in any direction. More specifically, for example, as shown in FIG. 5 (c), the irradiation light 70 from the point light source 102 can be made into parallel light 60 by the lens 104. [0083] The parallelism of the irradiation light is preferably set to a value of 10 ° or less. The reason is that by setting the parallelism of the irradiation light to a value within this range, a pillar structure can be formed efficiently and stably. Therefore, the parallelism of the irradiated light is more preferably set to a value of 5 ° or less, and further preferably set to a value of 2 ° or less. [0084] As the irradiation angle of the irradiation light, as shown in FIG. 6, the irradiation angle θ when the angle of the normal to the surface of the coating layer 1 is 0 ° is usually preferably -80 to Values in the range of 80 °. The reason is that if the irradiation angle is outside the range of -80 to 80 °, the influence of reflection and the like on the surface of the coating layer 1 becomes large, and it may be difficult to sufficiently form a pillar structure. The arrow MD in FIG. 6 indicates the moving direction of the coating layer. [0085] As the irradiation light of the active energy ray, ultraviolet rays are preferably used. The reason for this is the case of an electron beam. Since the polymerization rate is very fast, the components (A) and (B) cannot be sufficiently separated from each other during polymerization, and it may be difficult to form a column structure. On the other hand, when compared with visible light, the UV-curable resin that can be hardened by UV irradiation or the photopolymerization initiator that can be used are more abundant, so the components of (A) and (B) can be broadened. Select the amplitude. [0086] Further, as to the irradiation conditions of ultraviolet rays as the active energy ray, the peak illuminance of the surface coating layer is preferably set to 0.1 ~ 10mW / ² value within the range of the cm. The reason is that if the peak illuminance is less than 0.1 mW / cm ² , it may be difficult to clearly form a pillar structure. On the other hand, if the peak illuminance is a value exceeding 10 mW / cm ² , it is presumed that the curing rate is too fast, and it may be difficult to effectively form a column structure. Therefore, the lower limit of the peak illuminance on the surface of the coating layer is more preferably set to a value of 0.3 mW / cm ² or more, and more preferably to a value of 0.5 mW / cm ² or more. The upper limit of the peak illuminance on the surface of the coating layer is more preferably a value of 8 mW / cm ² or less, and even more preferably a value of 6 mW / cm ² or less. [0087] In addition, when the ultraviolet ray is used as the active energy ray, the accumulated light amount on the surface of the coating layer is preferably set to a value in a range of 5 to 200 mJ / cm ² . The reason is that if the accumulated light amount is less than 5 mJ / cm ² , it may be difficult to sufficiently extend the column structure from above to below. On the other hand, if the cumulative light amount exceeds a value of 200 mJ / cm ² , the obtained light diffusion control film may be colored. Thus, the surface of the integrated light quantity of the coating layer to better limit 7mJ / cm & lt value of ² or more, and better to 10mJ / ² values of more cm. In addition, the upper limit value of the accumulated light amount on the surface of the coating layer is more preferably a value of 150 mJ / cm ² or less, and even more preferably a value of 100 mJ / cm ² or less. [0088] From the viewpoint of maintaining mass productivity and stably forming a column structure, it is preferable that the coating layer formed on the step sheet is moved at a speed in the range of 0.1 to 10 m / min when irradiating ultraviolet rays as active energy rays. . It is particularly preferable to move at a speed of 0.2 m / min or more, and more preferably to move at a speed of 3 m / min or less. [0089] In the present invention, the internal structure formed in the light diffusion control film formed by curing the composition for light diffusion control film is not limited to the above if it includes a high refractive index region and a low refractive index region. Column construction. For example, when the louver structure 20b shown in FIG. 4 (a) is formed, as long as the coating layer 1 formed on the step sheet 2 is irradiated in one direction, it is substantially parallel light when viewed, and it looks non-parallel when viewed in other directions. The light of the stray light may be used as the irradiation light. In addition, when forming the specific internal structure 20d shown in FIG. 4 (c), as long as the coating layer 1 formed on the step sheet 2 is irradiated in one direction, it is substantially parallel light when viewed, and not all when viewed from other directions. The light may be a messy light but may be adjusted to a certain degree of parallelism. [Examples] [0090] Hereinafter, the present invention will be described in more detail through examples. However, the present invention is not limited to these descriptions. [Example 1] 1. Preparation of Overlay Laminated Film A biaxially-stretched polyethylene terephthalate film roll having a thickness of 38 μm and a short side direction (width direction) of 1000 mm was prepared (sometimes below) (Referred to as "film A") as the overlying laminated film. [0092] (1) Measurement of Phase Difference Re The phase difference Re of the overlying laminated film prepared was measured. That is, an arbitrary part in the longitudinal direction of the prepared over-clad film is specified as a measurement part. Next, among the specific measurement locations, 1000 locations along the short side direction and 20 locations per 50 mm were used as measurement points, and a phase difference Re (nm) was measured using a phase difference measuring device KOBRA-WR made by Oji Measurement Co., Ltd. The results obtained are shown in the characteristic curve A in FIG. 7. This FIG. 7 is a short-side position-phase difference Re graph using the horizontal axis as the position (mm) in the short-side direction of the overlying laminated film, and the vertical axis as the phase difference Re (nm). Then, from the obtained measured values, the median value (nm) of the phase difference Re and the deviation ((Re _max -Re _min ) / (Re _max + Re _min ) × 100) (%) expressed by the formula (1) were calculated. The results obtained are shown in Table 1. [0093] (2) Surface Roughness Rp and Ra The arithmetic average roughness (Ra) and the maximum ridge (Rp) of the prepared overlying laminated film were measured. That is, using the surface shape measuring device WYKO NT110 (ANSI B46.1 standard) manufactured by Veeco, the arithmetic average roughness (Ra) (nm) of the prepared overlying film was measured, and the maximum bulge (Rp) was measured. (nm). The results obtained are shown in Table 1. (3) Measurement of turbidity and total light transmittance The turbidity of the prepared overlying laminated film was measured. That is, the turbidity (%) and total light transmittance of the prepared overlying laminated film were measured using a turbidimeter NDH 5000 manufactured by Nippon Denshoku Industries Co., Ltd. The results obtained are shown in Table 1. [0095] 2. Synthesis of low-refractive-index active energy ray hardening component In a container, 1 mol of polypropylene glycol (PPG) having a weight average molecular weight of 9200 as (B2) component is stored as isophorone di (B1) component. After 2 mols of isocyanate (IPDI) and 2 hydroxyethyl methacrylate (HEMA) as (B3) components, the reaction was carried out according to a common method to obtain a polyether having a weight average molecular weight of 9900 as a component (B). Urethane methacrylate. [0096] The weight average molecular weight of polypropylene glycol and polyether urethane methacrylate is a polystyrene conversion value measured by gel permeation chromatography (GPC) under the following conditions. ． GPC measuring device: TOSOH (stock) system, HLC-8020. GPC column: made of TOSOH (share) (Through description below) TSK protective column HXL-H TSK gel GMHXL (× 2) TSK gel G2000HXL． Determination solvent: tetrahydrofuran. Measurement temperature: 40 ° C 3. Preparation of the composition for a light diffusion control film Next, o-phenylphenoxyethoxyethyl acrylate having a molecular weight of 268 represented by the above formula (3) was added as the component (A) Ester (62.5 parts by weight, manufactured by Shin Nakamura Chemical Co., Ltd., NK ESTER A-LEN-10) and 37.5 parts by weight of a polyether urethane methacrylate having a weight average molecular weight of 9,900 as a component (B) after synthesis For the total amount of (A) component and (B) component = 100 parts by weight of 1.25 parts by weight of 2-hydroxy-2-methyl-1-phenylpropane-1-one as component (C), then at 80 The mixture was heated and mixed under the condition of ℃ to obtain a composition for a light diffusion control film. The refractive indices of the components (A) and (B) are measured using an Abbe refractometer (manufactured by ATAGO Co., Ltd., Ab-Refractometer DR-M2, Na light source, and wavelength 589 nm). 1.58 and 1.46. [0098] 4. The coating step is followed by applying a peeling treatment to the transparent polyethylene terephthalate roll with a length of 1000 mm in the short-side direction as a step sheet, and applying the coating on the peeling treatment surface. The composition for a light diffusion control film forms a coating layer with a thickness of 60 μm. [0099] 5. Laminating Step Next, the exposed surface side of the coating layer is laminated with a prepared film by roll-to-roll lamination. Next, as shown in FIG. 5 (c), an ultraviolet point parallel light source (manufactured by JATEC) is used to control the parallelism of the central rays within ± 3 °, and the parallel light with a parallelism of 2 ° or less is shown in FIG. 6 The coating layer is irradiated so that the irradiation angle θx becomes approximately 10 °. The peak illuminance at this time was set to 2.00 mW / cm ² , the cumulative light amount was set to 53.13 mJ / cm ² , the lamp height was set to 1480 mm, and the moving speed of the coating layer was set to 1.0 m / min. In addition, the above-mentioned peak illuminance and cumulative light amount were measured by installing a UV meter (EYE GRAPHIC (Eye) Co., Ltd., EYE ultraviolet cumulative illuminance meter UVPF-A1)) provided with a photoreceptor at the position of the coating layer. The film thickness of the light diffusion control film was measured using a constant-pressure thickness measuring device (TECLOCK PG-02J, manufactured by Takara Seisakusho Co., Ltd.). [0100] A cross-sectional photograph of the light diffusion control film having the obtained pillar structure cut along a plane parallel to the moving direction of the coating layer and orthogonal to the film plane is shown in FIG. 8 (a). The length of the pillar structure in the film thickness direction was 60 μm, and the inclination angle thereof was 7 °. The cutting of the light diffusion control film was performed using a razor, and the photographing of the cross-section photograph was performed using a keyence product. The digital microscope VHX-1000 was performed by reflection observation. [0101] 6. Evaluation (1) Measurement of angle-varying turbidity The angle-varying turbidity of the obtained light diffusion control film was measured. That is, a short strip-shaped test piece (120 mm wide) in the long side direction was cut out from any part of the obtained sheet / light diffusion control film / overlay laminated film laminate, and used by Toyo Seiki Seisakusho Co., Ltd., Haze Gard Plus measures the angular turbidity (%). At this time, the distance between the opening of the integrating sphere and the light diffusion control film was set to 62 mm, and the incident point of the reference light was set to the center point in the short side direction of the light diffusion control film of the test piece. In addition, as shown in FIG. 9 (a), the reference light is incident from the sheet side of the test piece, and the incident angle of the reference light is changed along the longitudinal direction of the light diffusion control film and measured. The obtained results are shown in the characteristic curve A in Fig. 9 (b). FIG. 9 (b) is an incident angle-variable angle turbidity chart with the horizontal axis as the incident angle (°) of the reference light and the vertical axis as the variable angle turbidity (%). The width of the incident angle region with a turbidity of 70% or more was calculated from FIG. 9 (b) and shown in Table 1. Therefore, from the characteristic curve A, it is possible to confirm the property that the degree of light diffusion varies with the incident angle, that is, the incident angle dependency (characteristic curve B: Example 2, characteristic curve C: Same as Comparative Example 1). [0102] (2) Measurement of Straight Forward Transmission Light Intensity PT The direct transmission light intensity of the obtained light diffusion control film was measured. That is, the measurement point is 1000 mm along the short side of the same test piece as that used for the variable angle turbidity measurement, and a total of 20 locations are used as measurement points per 50 mm. The measurement is performed using a variable angle colorimeter VC-2 manufactured by SUGA testing machine (strand). Straight forward transmitted light intensity PT (%). At this time, as shown in FIG. 10 (a), for the step sheet side of the test piece, light was incident from the pillar oblique direction of the light diffusion control film in a direction inclined at an angle of 60 ° and measured. The obtained results are shown in the characteristic curve A in Fig. 10 (b). FIG. 10 (b) is a position (mm) in the short-side direction of the light diffusion control film on the horizontal axis, and a position in the short-side direction of the straight-through transmission light intensity (%)-a straight-through transmission light intensity chart. From the obtained measured values, the median value (%) of the linear transmitted light intensity PT and the deviation ((PT _max -PT _min ) / (PT _max + PT _min ) × 100) (%) expressed by the formula (1) were calculated. . The results obtained are shown in Table 1. [Example 2] In Example 2, a biaxially stretched polymer having a thickness of 38 μm having a phase difference Re and a surface roughness shown in Table 1 and a length of 1,000 mm in the short side direction was used as the overlying laminated film in addition to the overlying laminated film. Except for a terephthalate roll (hereinafter, sometimes referred to as a film B), a laminate was produced and evaluated in the same manner as in Example 1. The obtained results are shown in Table 1, the characteristic curve B of FIG. 8 (b), FIG. 9 (b), and the characteristic curve B of FIG. 10 (b). [Comparative Example 1] In Comparative Example 1, a biaxially stretched polymer having a thickness of 75 mm having a phase difference Re and a surface roughness shown in Table 1 and a length of 1,000 mm in the short-side direction was used as the overlying laminated film. Except for a terephthalate roll (hereinafter sometimes referred to as "film C"), a laminate was produced and evaluated in the same manner as in Example 1. The obtained results are shown in Table 1, the characteristic curve C of FIG. 8 (b), FIG. 9 (b), and the characteristic curve C of FIG. 10 (b). [0105] [Industrial Applicability] As described in detail above, according to the present invention, by setting the deviation of the phase difference measured in a specific direction in the surface of the overlying laminated film to a value within a specific range, In the case where no internal structure region is not formed, or in the case where it occurs, the internal structure can be uniformly formed. As a result, a light diffusion control film having uniform light diffusion characteristics regardless of the internal position of the film surface can be obtained. Therefore, the light diffusion control film obtained by the present invention is expected to contribute significantly to the improvement of the quality of a liquid crystal display device, a projection screen, and the like.

[0107]

1‧‧‧ coated layer

2‧‧‧ step flakes

10‧‧‧light diffusion control film

10a‧‧‧Isotropic light diffusion control film

10b ～ 10d‧‧‧‧Light diffusion control film

12, 12b ～ 12d‧‧‧‧ area with relatively high refractive index (including plate-shaped area with relatively high refractive index)

12a‧‧‧ relatively high refractive index pillars

14, 14a to 14d ‧‧‧ areas with relatively low refractive index (including plate-shaped areas with relatively low refractive index)

16‧‧‧ Bend

20‧‧‧ Internal structure

20a’‧‧‧ boundary surface

20a‧‧‧column structure

20b‧‧‧ Blind structure

20c‧‧‧curved column structure

20d‧‧‧Specific internal structure

52, 54‧‧‧ incident light

52 ’, 54’ ‧‧‧ specific diffused light

56‧‧‧ incident light

56’‧‧‧ through light

60‧‧‧ Parallel Light

70‧‧‧ radiated light from a point light source

100‧‧‧ laminated

102‧‧‧point light source

104‧‧‧Lens

[0018] FIG. 1 (a) to (b) are diagrams for explaining the outline of the laminated body of the present invention. FIGS. 2 (a) to 2 (b) are diagrams for explaining the outline of a light diffusion control film having a pillar structure in the film. FIGS. 3 (a) to 3 (b) are diagrams for explaining the dependency of the incident angle and the isotropic light diffusion in a light diffusion control film having a pillar structure in the film. FIGS. 4 (a) to 4 (d) are diagrams for explaining the state of the internal structure in the light diffusion control film of the present invention. (5) FIGS. 5 (a) to (c) are diagrams for explaining a method for producing a laminated body of the present invention. FIG. 6 is a diagram for explaining an irradiation angle of an active energy ray. FIG. 7 is a diagram for showing the relationship between the position in the width direction of the overlying laminated film and the retardation Re in Example 1 and Comparative Example 1. 8 (a) to 8 (c) are views for showing photographs of cross sections of the light diffusion control films in Examples 1 to 2 and Comparative Example 1. FIGS. 9 (a) to (b) are diagrams for showing the relationship between the incident angle of the reference light to the light diffusion control film and the variable-angle turbidity in Examples 1 to 2 and Comparative Example 1. (FIGS. 10 (a) to (b) are diagrams for showing the relationship between the position in the short-side direction of the light diffusion control films in Examples 1 to 2 and Comparative Example 1 and the intensity of P.T.

Claims (7)

A laminated body is a laminated body in a state where an overlying laminated film is laminated on at least one side of a light diffusion controlling film derived from a composition for a light diffusion controlling film, characterized in that the light diffusion controlling film has a low refractive index. The high-refractive-index region has an internal structure having a plurality of high-refractive-index regions and the high-refractive-index region extends in the thickness direction, and the moving direction when the light diffusion control film is formed in the lamination plane of the laminate is set to the long side direction. A direction perpendicular to the long side direction is set to a short side direction, and a maximum value of the phase difference Re (nm) measured along the short side direction of the above-mentioned laminated film is set to Re _max and the minimum value is set to Re _min In this case, the following relational expression (1) is satisfied, and (Re _max −Re _min ) / (Re _max + Re _min ) × 100 <35 (%) (1). For example, the laminated body of claim 1, wherein the length in the short-side direction of the overlying laminated film is a value in a range of 100 to 10,000 mm. For example, the laminated body of claim 1 or 2, wherein the central value of the phase difference Re of the above-mentioned laminated film is a value in the range of 1000 to 3000 nm. For example, the layered product of claim 1 or 2, wherein the film thickness of the aforementioned overlying laminated film is a value in a range of 5 to 5000 μm. For example, the laminated body of claim 1 or 2, wherein the internal structure of the aforementioned light diffusion control film is included in a region with a relatively low refractive index, and a plurality of pillars having a relatively high refractive index are lined in the film thickness direction. Pillar structure. For example, the laminated body of claim 1 or 2, wherein the internal structure of the light diffusion control film includes a louver structure formed by alternately arranging a plurality of plate-shaped regions having different refractive indexes along any direction of the film surface. A method for manufacturing a laminate, which is characterized in that it is the method for manufacturing a laminate according to any one of claims 1 to 6, and includes the following steps (a) to (d), (a) preparing to include active energy of high refractive index The step of forming a composition for a light-diffusion control film of a linear hardening component and a low-refractive index active energy ray-hardening component, (b) a step of forming a coating layer by applying the aforementioned composition for a light-diffusion control film in a thin film form, ( c) For the step of laminating the exposed surface of the coating layer that satisfies the above-mentioned relational formula (1), a step of laminating the laminated film, (d) while moving the coating layer, passing through the upper laminating film, The step of irradiating the coating layer with active energy rays.