Multilayer laminated film

Abstract

To provide a multilayer laminate film which achieves high lamination accuracy as designed over a wide range in a width direction of a film, and has a uniform reflectance spectrum over the wide range in the width direction of the film, and a molding using the multilayer laminate film.SOLUTION: There is provided a multilayer laminate film in which 51 or more layers of a plurality of different thermoplastic resin layers are alternately stacked, wherein when a surface of a film having the more number of layers when the multilayer laminate film is divided into two with the same thickness is represented by a surface 1, a surface of a film having the less number of layers is represented by a surface 2, and a layer group positioned in a range of 15% to 30% of a section from the surface 1 to the surface 2 is represented by a layer group La, the layer group La includes 50% or more of a layer with a thickness of lower 10% in a layer with a thickness of 1 nm or more and 1,000 nm or less constituting the multilayer laminate film.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a multilayer laminated film, a multilayer laminated film roll, and a molded article using the same, in which changes in optical properties in the width direction are reduced. [Background technology]

[0002] Multilayer laminated films, formed by alternately stacking multiple different thermoplastic resin layers using a melt deposition method, can reflect light of various wavelengths by controlling the refractive index and layer thickness of the stacked thermoplastic resin layers. However, multilayer laminated films produced by the melt deposition method have a lower refractive index difference between different thermoplastic resin layers compared to conventional multilayer films produced by inorganic material vapor deposition. Therefore, multilayer laminated films require not only a large number of layers but also the realization of a multilayer film structure with high stacking accuracy as designed optically, due to differences in the stacking method. To address these challenges, a multilayer laminated film in which the multilayer film is stacked using a feed block has been proposed as a method for obtaining a multilayer laminated film with high stacking accuracy (Patent Document 1). [Prior art documents] [Patent Documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2007-176154 [Overview of the project] [Problems that the invention aims to solve]

[0004] The multilayer laminated film disclosed in Patent Document 1 achieves high lamination accuracy as designed in the central part in the width direction. However, in this multilayer laminated film, the lamination accuracy deviates from the design as it moves from the central part in the width direction toward the edges. As a result, it is not possible to achieve the desired reflectance spectrum near the edges in the width direction, resulting in a problem of low product width yield. In other words, the object of the present invention is to provide a multilayer laminated film that has high lamination accuracy even near the edges in the width direction and excellent product width yield. [Means for solving the problem]

[0005] To solve the above problems, the present invention has the following configuration. That is, a multilayer laminated film in which 51 or more layers of different thermoplastic resin layers are alternately laminated, wherein when the multilayer laminated film is divided in half so that the thickness is equal, the surface with more layers is designated as Surface 1, the surface with fewer layers is designated as Surface 2, and the group of layers located in the range of 15% to 30% of the section from Surface 1 to Surface 2 is designated as layer group La, and layer group La contains 50% or more of the layers with the bottom 10% thickness among the layers with a thickness of 1 nm to 1000 nm that constitute the multilayer laminated film.

[0006] Furthermore, the multilayer laminated film of the present invention can be in the following forms, or it can be made into a multilayer laminated film roll or a molded article. (1) A multilayer laminated film comprising 51 or more layers of different thermoplastic resin layers stacked alternately, wherein when the multilayer laminated film is divided in half so that the thicknesses are equal, the surface with more layers is designated as Surface 1, the surface with fewer layers as Surface 2, and the group of layers located in the range of 15% to 30% of the interval from Surface 1 to Surface 2 is designated as Layer Group La, and Layer Group La comprises 50% or more of the layers with the lowest 10% thickness among the layers with a thickness of 1 nm to 1000 nm that constitute the multilayer laminated film. (2) The multilayer laminated film according to (1), wherein when the group of layers located in the range of 75% to 85% of the interval from surface 1 to surface 2 is called layer group Lb, layer group Lb includes 70% or more of the layers that make up the top 10% of the layers with a thickness of 1 nm or more and 1000 nm or less that constitute the multilayer laminated film. (3) The multilayer laminated film according to (1) or (2), wherein when the group of layers located in the range of 30% to 75% of the section from surface 1 to surface 2 is called the layer group Lc, the thickness of the layers constituting the layer group Lc has a gradient structure. (4) When the layer group located in the section from the surface 1 to the starting point of the layer group La is defined as the layer group Ld, and the layer group located in the section from the end point of the layer group Lb to the surface 2 is defined as the layer group Le, the thicknesses of the layers constituting the layer group Ld and the layer group Le both have an inclined structure, the average layer thickness of the layer group Ld and the average layer thickness of the layer group Le both exceed the average layer thickness of the layer group La and are less than the average layer thickness of the layer group Lb, and the maximum layer thickness in the layer group Ld is 0.7 times or more the minimum layer thickness in the layer group Le. The multilayer laminated film according to any one of (1) to (3). (5) Having a structure in which a layer (layer A) made of a first thermoplastic resin and a layer (layer B) made of a second thermoplastic resin are alternately laminated, the first thermoplastic resin being mainly composed of a crystalline polyester, and the layer B being mainly composed of an amorphous polyester or a crystalline polyester having a melting point 5°C to 100°C lower than that of the thermoplastic resin constituting the layer A. The multilayer laminated film according to any one of (1) to (4). (6) Having a reflection peak with a reflectance of 30% or more and 100% or less continuously over 5 nm or more in the wavelength range of 240 nm to 2600 nm. The multilayer laminated film according to any one of (1) to (5). (7) The average reflectance in the wavelength range of 400 nm to 800 nm is 20% or more and 100% or less. The multilayer laminated film according to any one of (1) to (6). (8) The transmittance of visible light incident perpendicularly to the multilayer laminated film surface is 80% or more and 100% or less. When the reflectances (%) of the respective P waves when visible light is incident at angles of 20°, 40°, and 60° with respect to the normal of the multilayer laminated film surface are Rp20, Rp40, and Rp60, respectively, the relationship Rp20 ≦ Rp40 < Rp60 is satisfied, and Rp60 is 10% or more and 100% or less. The multilayer laminated film according to any one of (1) to (7). (9) The chroma of the reflected light of the P wave when incident at an angle of 60° with respect to the normal of the multilayer laminated film is 0 or more and 20 or less. The multilayer laminated film according to (1) to (8). (10) The azimuth variation of Rp60 is 0.1% or more and 10% or less. The multilayer laminated film according to (8) or (9). (11) A multilayer laminated film roll formed by winding a multilayer laminated film described in any of (1) to (10) onto a core. (12) A multilayer laminated film roll as described in (11), wherein the width of the multilayer laminated film is 1 m or more and the length is 100 m or more. (13) A molded article using a multilayer laminated film described in any of (1) to (10) or a multilayer laminated film roll described in (11) or (12). [Effects of the Invention]

[0007] According to the present invention, high lamination accuracy as designed can be ensured over a wide range in the width direction, making it possible to obtain a multilayer laminated film with a more uniform reflectance spectrum over a wide range in the width direction. Furthermore, multilayer laminated film rolls and molded articles can also be obtained from the above multilayer laminated film. [Brief explanation of the drawing]

[0008] [Figure 1] This figure illustrates the differences in layer thickness distribution and reflectance spectrum depending on the position in the width direction in an example of a multilayer laminated film using conventional technology. [Figure 2] This is a schematic diagram illustrating the definition of the layer thicknesses of the layer groups La, Lb, Lc, Ld, and Le. [Figure 3] This figure illustrates the layer thickness distribution and reflectance spectrum of a multilayer laminated film according to one embodiment of the present invention. [Figure 4] This figure illustrates the layer thickness distribution and reflectance spectrum of a multilayer laminated film according to one embodiment of the present invention. [Figure 5] This is a schematic diagram illustrating the layer thickness distribution of layer A and layer B in the multilayer laminated film of the present invention, which is used to set the chrominance of reflected P-wave light to 20 or less. [Figure 6] This is a schematic diagram illustrating the orientation angle of the multilayer laminated film of the present invention. [Figure 7] This figure shows the design of the layer thickness at the center position in the width direction of the multilayer laminated films of Examples 1 to 5. [Figure 8]It is a diagram showing the design of the layer thickness at the central position in the width direction of the multilayer laminated films of Examples 6 to 10. [Figure 9] It is a diagram showing the design of the layer thickness at the central position in the width direction of the multilayer laminated films of Examples 11 to 16 and Example 19. [Figure 10] It is a diagram showing the design of the layer thickness at the central position in the width direction of the multilayer laminated films of Examples 17 and 18. [Figure 11] It is a diagram showing the design of the layer thickness at the central position in the width direction of the multilayer laminated films of Comparative Examples 1 to 5.

Mode for Carrying Out the Invention

[0009] The multilayer laminated film of the present invention is a multilayer laminated film in which a plurality of different thermoplastic resin layers are alternately laminated 51 layers or more. When the multilayer laminated film is bisected so that the thickness is equal, the surface with more layers is designated as Surface 1, and the surface with fewer layers is designated as Surface 2. When a layer group located in the range of 15% to 30% of the section from Surface 1 to Surface 2 is designated as layer group La, layer group La includes 50% or more of the layers having a thickness in the lower 10% among the layers having a thickness of 1 nm or more and 1000 nm or less that constitute the multilayer laminated film.

[0010] In addition, the multilayer laminated film of the present invention only needs to satisfy the above requirements except for the number of laminated layers in a part of the entire film. However, from the viewpoint of having a more uniform reflectance spectrum over a wide range in the width direction, it is preferable to satisfy both at the central position in the width direction and at at least one end position in the width direction. This also applies to other characteristics (excluding characteristics determined by the layer structure, composition of each layer, and components of each layer) that the multilayer laminated film of the present invention can have, which will be described below. The end position in the width direction refers to a position shifted 0.5 m in the direction of either end in the width direction from the central position in the width direction. The same applies to the multilayer laminated film roll described later.

[0011] Embodiments of the present invention are described below, but the present invention is not limited to the embodiments described below, and various modifications are naturally possible as long as they achieve the objective of the invention and do not depart from the spirit of the invention. Also, for the purpose of simplifying the explanation, some of the explanations will be given using a multilayer laminated film having a structure in which two different thermoplastic resin layers are alternately laminated, which is one of the preferred embodiments of the present invention, as an example, but the same should be understood when three or more thermoplastic resins are used.

[0012] The multilayer laminated film of the present invention must have a structure in which 51 or more layers of different thermoplastic resins are laminated alternately. In the multilayer laminated film of the present invention, if there are multiple types of thermoplastic resin layers with different compositions, and the refractive indices of these thermoplastic resin layers differ by 0.01 or more in any two orthogonal directions arbitrarily selected within the plane of the film and in a direction perpendicular to the plane, then it can be considered that "multiple different thermoplastic resin layers exist." Furthermore, "laminated alternately" means that layers made of different thermoplastic resins are laminated in a regular arrangement in the thickness direction.

[0013] Specific examples of such embodiments include cases where a multilayer laminated film consists of a layer made of a first thermoplastic resin (layer A) and a layer made of a second thermoplastic resin (layer B), where the layers are stacked in the order A(BA)n, B(AB)n (where n is a natural number representing a repeating unit, the same applies hereinafter). Alternatively, if a multilayer laminated film consists of a layer made of a first thermoplastic resin (layer A), a layer made of a second thermoplastic resin (layer B), and a layer made of a third thermoplastic resin (layer C), the arrangement is not particularly limited, but examples include cases where each layer is stacked in the order with a certain regularity, such as C(BA)nC, C(ABC)n, C(ACBC)n, etc. By alternately stacking multiple thermoplastic resin layers with different optical properties such as refractive index in this way, it becomes possible to produce interference reflection that selectively reflects light in a desired wavelength band based on the relationship between the difference in refractive index of each layer and the layer thickness.

[0014] Furthermore, if the number of layers in a multilayer laminated film is 50 or less, high reflectivity cannot be obtained in the desired wavelength band. As mentioned above, interference reflection can achieve higher reflectivity for light in a wider wavelength band as the number of layers increases, and a multilayer laminated film that reflects light in the desired wavelength band can be obtained. From the above viewpoint, the number of layers in a multilayer laminated film is preferably 201 or more, more preferably 401 or more, and even more preferably 801 or more. Although there is no upper limit to the number of layers, as the number of layers increases, manufacturing costs increase due to the need for larger manufacturing equipment, and handling deteriorates due to the thickness of the film. Therefore, in reality, around 10001 layers is within the practical range.

[0015] The laminated structure of the multilayer laminated film of the present invention, comprising 51 or more layers, can be manufactured by the following method. First, a first thermoplastic resin and a second thermoplastic resin are supplied in a molten state from two extruders, Extruder A corresponding to layer A and Extruder B corresponding to layer B. The molten thermoplastic resins supplied from each flow path are alternately laminated in 51 or more layers using a known lamination device, which consists of a multi-manifold type feed block and a square mixer, or only a comb type feed block. Next, the molten laminate is extruded into a sheet shape using a T-type die or the like, and cooled and solidified on a casting drum to obtain an unstretched multilayer laminated film. As a method for improving the lamination accuracy of layers A and B, the lamination methods described in Japanese Patent Publication No. 2007-307893, Japanese Patent No. 4691910, and Japanese Patent No. 4816419 are preferred. With such a lamination method, high lamination accuracy as designed can be achieved in the central part of the film in the width direction. Here, the width direction refers to the direction perpendicular to the direction in which the film travels (longitudinal direction) during the manufacturing process within the film plane.

[0016] Immediately after lamination using the above lamination method, each layer is laminated to the designed thickness at both the center and edge positions in the width direction. However, because thermoplastic resins in different molten states are laminated alternately, differences in flow characteristics occur between the center and edge positions in the width direction due to the differences in the rheological properties of the thermoplastic resins before they are extruded from the lamination device through the die. This difference in flow characteristics causes a difference in layer thickness between the center and edge positions in the width direction, resulting in a deviation from the design in lamination accuracy as you move from the center to the edge in the width direction of the film. When a multilayer laminated film is manufactured with such a deviation from the design, the desired reflectance spectrum cannot be obtained near the edges in the width direction, and the resulting multilayer laminated film is ultimately limited to the portion close to the center in the width direction, resulting in a low product width yield.

[0017] The following will explain the problems of the conventional technology in more detail with reference to the drawings. Figure 1 is a diagram illustrating the layer thickness distribution and the difference in reflectance spectrum depending on the position in the width direction in an example of a multilayer laminated film using the conventional technology. The multilayer laminated film in Figure 1 is a multilayer laminated film in which 401 layers of two different types of resins (layer A: polyethylene terephthalate with an in-plane refractive index of 1.66, layer B: copolymerized polyethylene terephthalate with an in-plane refractive index of 1.55) are alternately laminated, designed to reflect light in the wavelength band from 850 nm to 1150 nm and transmit light in the wavelength band from 400 nm to 800 nm. The refractive index referred to here is the value measured by an Abbe refractometer when irradiated with sodium D line (wavelength 589 nm).

[0018] Figure 1A shows the average layer thickness (nm) of adjacent layers A and B at the layer thickness position (%) from surface 1 to surface 2 of a multilayer laminated film. Hereinafter, the "average layer thickness of adjacent layers A and B" may be referred to as the "average layer-to-layer thickness". Figure 1B shows the reflectance spectrum of the multilayer laminated film showing the average layer-to-layer thickness shown in Figure 1A. Here, surface 1 refers to the surface with more layers when the multilayer laminated film is divided into two halves with equal thickness, and surface 2 is the surface with fewer layers. When determining the average layer-to-layer thickness, the layer pairs are determined by first defining the layer closest to surface 1 and its adjacent layer (on the surface 2 side) among the layers forming the alternating laminated unit, and then sequentially defining the layer pairs toward the surface 2 side. In this case, any remaining layers that occur when the total number of layers forming the alternating laminated unit is odd are treated as non-existent because they cannot form a layer pair.

[0019] As shown in Figure 1A, the average layer thickness (indicated by 1) at the center of the width direction increases linearly from surface 1 (0%) to surface 2 (100%) in the range of 130 nm to 180 nm. As a result, as shown in the reflectance spectrum (indicated by 3) at the center of the width direction, the multilayer laminated film at the center of the width direction reflects light in the wavelength band from 850 nm to 1150 nm sharply and to almost the same extent. On the other hand, the average layer thickness (indicated by 2) at the edges of the width direction differs from that at the center of the width direction. As a result, in the reflectance spectrum (indicated by 4) at the edges of the width direction, both the low-wavelength and long-wavelength edge wavelengths of the reflection band are shifted to the long-wavelength side compared to the center, and the reflectance around 1100 nm is further reduced. Here, the reflection band refers to the wavelength band where the reflectance is 30% or more. The low-wavelength edge wavelength is the wavelength that exhibits half the reflectance (half-value) of the maximum reflectance in the reflection band, and is the wavelength on the lowest wavelength side. The high-wavelength edge wavelength is the wavelength that exhibits the same half-value, and is the wavelength on the highest wavelength side.

[0020] Thus, with conventional techniques, it is difficult to obtain a multilayer laminated film with the desired reflectance spectrum near the edges in the width direction, resulting in a problem of low product width yield. To solve this problem, the multilayer laminated film of the present invention requires that when the multilayer laminated film is divided in half so that the thickness is equal, the surface with more layers is designated as Surface 1, the surface with fewer layers as Surface 2, and the group of layers located in the range of 15% to 30% of the section from Surface 1 to Surface 2 is designated as Layer Group La, then Layer Group La must contain 50% or more of the layers with the lowest 10% thickness among the layers with a thickness of 1 nm to 1000 nm that constitute the multilayer laminated film. The layer configuration and the thickness of each layer can be identified and measured by observation using a transmission electron microscope (TEM), measurement using its length-measuring function, and image processing of a sample cut from a cross-section perpendicular to the film surface. Details will be described later in the examples.

[0021] Here, with respect to layer group La and subsequent layer groups Lb, Lc, Ld, and Le, the definition of layer thickness when calculating the layer that makes up the bottom 10% of the thickness for layer group La, the definition of layer thickness when calculating the layer that makes up the top 10% of the thickness for layer group Lb, the definition of layer thickness when calculating the thickness gradient structure of the layers constituting layer group Lc, and the definition of layer thickness when calculating the average layer thickness and maximum / minimum layer thickness for layer groups Ld and Le will be explained using Figure 2. Figure 2 is a schematic diagram to explain the definition of layer thickness for layer groups La, Lb, Lc, Ld, and Le. In Figure 2, reference numerals 5 to 7 represent, in order, the cross-sections of the first to eighth layers on the surface 1 side of the multilayer laminated film, layer A, and layer B, with the uppermost surface in the figure being surface 1.

[0022] The multilayer laminated film shown in the laminated configuration of reference numeral 5 has a structure in which the outermost layer on the surface 1 side is layer A, with layer B located adjacent to it, and thereafter layers A and B are repeated alternately. Let the thicknesses of the nth layer A and layer B from surface 1 be Han and Hbn, respectively (i.e., the layer thicknesses of each layer shown in reference numeral 5 are Ha1, Hb1, Ha2, Hb2, Ha3, Hb3, Ha4, and Hb4 in order from the layer on the surface 1 side). Layers A and B with the same "n" are considered as adjacent layers and a pair of layers, and the average thickness of each pair of layers is taken as Hn (i.e., in the configuration shown in reference numeral 5, the average value of Ha1 and Hb1 is H1, and similarly H2, H3, and H4 are determined thereafter). Since the reflection wavelength of the multilayer laminated film is determined by equation (A) below, adjusting the average layer thickness of adjacent layers A and B is important for controlling the reflection wavelength. Therefore, in this invention, the thickness of each layer included in each layer group is considered to be the average layer thickness of layer A and layer B that form a layer pair, respectively (that is, in the configuration indicated by reference numeral 5, the thicknesses of the layers from the surface 1 side are considered to be H1, H1, H2, H2, H3, H3, H4, H4. If there are n layers, the thicknesses of layer A and layer B that form the last layer pair will both be considered to be Hn).

[0023]

number

[0024] Here, λ is the reflected wavelength, n A d is the refractive index of layer A, A n is the thickness of layer A. B is the refractive index of layer B, d B This is the thickness of layer B.

[0025] In the multilayer laminated film of the present invention, the layer group located in the range of 15% to 30% of the section from surface 1 to surface 2 is defined as layer group La, the layer group located in the range of 75% to 85% of the same section is defined as layer group Lb, the layer group located in the range of 30% to 75% of the same section is defined as layer group Lc, the layer group located in the section from surface 1 to the starting point of layer group La is defined as layer group Ld, and the layer group located in the section from the end point of layer group Lb to surface 2 is defined as layer group Le. Furthermore, using the layer thicknesses of layers A and B included in the section from surface 1 to surface 2 of the multilayer laminated film defined above, it is possible to determine whether layer group La includes 50% or more of the layers that make up the bottom 10% of the layers with a thickness of 1 nm to 1000 nm that constitute the multilayer laminated film, and whether the other layer groups satisfy the respective requirements (described later). If a pair of layers exists across the boundary of a layer group, that pair of layers shall be considered to belong to the layer group closer to surface 1.

[0026] Hereinafter, one embodiment of the multilayer laminated film of the present invention will be described with reference to Figure 3. Figure 3 is a diagram illustrating the layer thickness distribution and reflectance spectrum of a multilayer laminated film according to one embodiment of the present invention. The multilayer laminated film shown in Figure 3, which has a layer thickness distribution and reflectance spectrum, is a multilayer laminated film in which 401 layers of two different types of thermoplastic resin layers (layer A: polyethylene terephthalate layer with an in-plane refractive index of 1.66, layer B: copolymer polyethylene terephthalate layer with an in-plane refractive index of 1.55) are alternately laminated, designed to reflect wavelengths from 850 nm to 1150 nm and transmit wavelengths from 400 nm to 800 nm. The refractive index here is the value measured by an Abbe refractometer when irradiated with sodium D line (wavelength 589 nm). From the layer thickness distribution shown in Figure 3A, it can be seen that layer group La (a group of layers located in the range of 15% to 30% of the section from surface 1 to surface 2) contains more than 50% of the layers with a thickness of 1 nm to 1000 nm that constitute the multilayer laminated film, specifically the layers with the lower 10% thickness.

[0027] As mentioned above, the reflection wavelength of a multilayer laminated film is determined by equation (A). Generally, the refractive indices of layers A and B in a multilayer laminated film do not differ significantly in each alternately stacked layer. Therefore, the reflection wavelength of a multilayer laminated film is greatly influenced by the thickness of each layer. Furthermore, considering that, according to the principle of interference reflection, reflection on the low-wavelength side is brought about by relatively thin layers, and conversely, reflection on the high-wavelength side is brought about by relatively thick layers, the low-wavelength edge of the reflectance spectrum is mainly determined by the layers with a thickness of 1 nm to 1000 nm that make up the multilayer laminated film, with the thickness mainly in the bottom 10%. Therefore, by suppressing the change in the thickness of the thin layers at the edges in the width direction with such a layer thickness configuration, the low-wavelength edge of the reflectance spectrum will be close to the central position even at the edges in the width direction of the multilayer laminated film. As a result, the shift of the low-wavelength edge of the reflectance spectrum can be reduced even at the edges in the width direction compared to conventional technology.

[0028] From the above viewpoint, it is more preferable that the multilayer laminated film of the present invention has a configuration in which the layer group La includes 80% or more of the layers that make up the bottom 10% of the thickness of the layers with a thickness of 1 nm to 1000 nm that constitute the multilayer laminated film. As the proportion of layers with a thickness of the bottom 10% included in the layer group La increases, the change in wavelength at the low wavelength edge becomes smaller at the central position and the edge position in the width direction, so there is no upper limit, and the upper limit is practically 100%. Furthermore, to adjust the reflective properties of the multilayer laminated film, it is also effective to adjust the refractive index difference between the two thermoplastic resin layers, the number of layers, the layer thickness distribution, and the film formation conditions (e.g., stretching ratio, stretching speed, stretching temperature, heat treatment temperature, heat treatment time).

[0029] In the multilayer laminated film of the present invention, when the layer group Lb is defined as the group of layers located in the range of 75% to 85% of the section from surface 1 to surface 2, it is preferable that the layer group Lb includes 70% or more of the layers with a thickness of 1 nm to 1000 nm that constitute the multilayer laminated film, specifically the layers that make up the top 10% of the thickness. The details of the above embodiment will be explained below with reference to Figure 4.

[0030] Figure 4 illustrates the layer thickness distribution and reflectance spectrum of a multilayer laminated film according to one embodiment of the present invention. The multilayer laminated film shown in Figure 4, which has a layer thickness distribution and reflectance spectrum, is a multilayer laminated film in which 401 alternating layers of two different resins (Layer A: polyethylene terephthalate with an in-plane refractive index of 1.66, Layer B: copolymerized polyethylene terephthalate with an in-plane refractive index of 1.55) are laminated, designed to reflect light in the wavelength band from 850 nm to 1150 nm and transmit light in the wavelength band from 400 nm to 800 nm. The refractive index referred to here is the value measured by an Abbe refractometer when irradiated with sodium D line (wavelength 589 nm).

[0031] From the layer thickness distribution shown in Figure 4, it can be seen that layer group Lb (the layer group located in the range of 75% to 85% of the section from surface 1 to surface 2) contains more than 70% of the layers with thicknesses of 1 nm to 1000 nm that make up the multilayer laminated film, specifically the layers with the top 10% thickness. As mentioned above, according to the principle of interference reflection, reflection on the high-wavelength side is brought about by relatively thicker layers. Therefore, as shown in Figure 4A, by configuring layer group Lb to contain many relatively thick layers, the change in the long-wavelength end of the reflectance spectrum at the widthwise edge can be reduced by suppressing the thickness change of the thicker layers at the widthwise edge.

[0032] In the multilayer laminated film of the present invention, when a layer group located in the range of 30% to 75% of the section from surface 1 to surface 2 is defined as layer group Lc, it is preferable that the thickness of the layers constituting layer group Lc has an inclined structure. Here, the inclined structure means that, macroscopically, for the average layer thickness (nm) of adjacent layers A and B at the layer thickness position (%) from surface 1 of the multilayer laminated film, it has an inclined structure. Here, having an inclined structure macroscopically means that when taking the layer thickness position (%) from surface 1 on the horizontal axis and the average layer thickness (nm) of adjacent layers A and B on the vertical axis, the slope XLc of its first-order approximation formula is 0.1 or more (the same applies to the inclined structures of other layer groups described later). By having the thickness of the layers constituting layer group Lc have an inclined structure, the reflectance at wavelengths between the short-wavelength end wavelength and the long-wavelength end wavelength can be efficiently increased, and the uniformity of the reflectance from the short-wavelength end wavelength to the long-wavelength end wavelength can be enhanced.

[0033] The preferable value of the slope XLc of the first-order approximation formula is that when XLab = (average layer thickness of layer group La - average layer thickness of layer group Lb) (nm) / (75 - 30) (%), it is preferable that -XLab < XLc ≤ -XLab × 0.7 or XLab × 0.7 ≤ XLc < XLab. By having XLc within the above-mentioned range, the layer thickness between layer group La that mainly reflects light at wavelengths near the short-wavelength end and layer group Lb that mainly reflects light at wavelengths near the long-wavelength end can be filled uniformly, and the uniformity of the reflectance from the short-wavelength end wavelength to the long-wavelength end wavelength can be enhanced.

[0034] In the multilayer laminated film of the present invention, when a layer group located in the section from surface 1 to the starting point of layer group La is defined as layer group Ld, and a layer group located in the section from the end point of layer group Lb to surface 2 is defined as layer group Le, it is preferable that the thicknesses of the layers constituting layer group Ld and the layer group Le both have an inclined structure, the average layer thickness of layer group Ld and the average layer thickness of layer group Le both exceed the average layer thickness of layer group La and are less than the average layer thickness of layer group Lb, and the maximum layer thickness in layer group Ld is 0.7 times or more the minimum layer thickness in the layer group Le.

[0035] The layer thicknesses constituting the layer groups Ld and Le have a gradient structure, and by making the maximum layer thickness in layer group Ld at least 0.7 times the minimum layer thickness in layer group Le, the layer thickness between layer group La, which mainly reflects light near the low wavelength end, and layer group Lb, which mainly reflects light near the long wavelength end, can be uniformly filled. Therefore, the reflectance at wavelengths between the low and long wavelength end can be efficiently increased, and the uniformity of reflectance from the low to long wavelength end can be improved.

[0036] The gradient structure of the layer groups Lc, Ld, and Le is preferably such that the layer thickness distribution changes linearly, geometrically, or in a continuously changing manner, such as a difference sequence, or that 10 to 50 layers have roughly the same thickness, with the thickness changing in a step-like manner.

[0037] There are no particular limitations on the method for forming the layer group La~Le as described above, but for example, a method can be used in which layers A and B made of two types of resin are laminated using the feed block method described in Japanese Patent Publication No. 2007-307893, Japanese Patent No. 4691910, and Japanese Patent No. 4816419, and the slit width, slit gap, and slit length of the lamination apparatus are adjusted according to the desired layer group configuration.

[0038] Preferably, protective layers with a thickness of 1% or more of the thickness of the multilayer laminated film can be provided on both surface layers of the multilayer laminated film. Preferably, the thickness of the protective layer on surface 1 is 4% or more of the total thickness of the multilayer laminated film. On the other hand, if the thickness of the protective layer on surface 1 exceeds 15% of the distance from surface 1 to surface 2, it becomes difficult for the layer group La to include 50% or more of the layers with a thickness of 1 nm to 1000 nm that constitute the multilayer laminated film, specifically the layers in the lower 10% thickness range. Therefore, it is preferable that the thickness of the protective layer be less than 15% of the total thickness of the multilayer laminated film.

[0039] Similarly, if the thickness of the protective layer on surface 2 is less than 85% of the distance from surface 1 to the surface (or conversely, more than 15% when surface 2 is considered 0%), it becomes difficult for layer group Lb to include 70% or more of the layers that make up the top 10% of the thickness of the layers with a thickness of 1 nm to 1000 nm that constitute the multilayer laminated film. Therefore, it is preferable that the thickness of the protective layer be less than 15% of the total thickness of the multilayer laminated film. A thicker protective layer leads to suppression of flow marks during film formation, improved accuracy of the actual layer thickness of each layer relative to the design, suppression of deformation of the thin film layer in the multilayer laminated film during and after the lamination process with other films or molded products, and improved pressure resistance.

[0040] The thickness of the multilayer laminated film of the present invention is not particularly limited, but is preferably, for example, 20 μm to 300 μm. When the thickness is 20 μm or more, the stiffness of the multilayer laminated film is increased, ensuring good handling. When the thickness is 300 μm or less, the stiffness of the multilayer laminated film is not excessively strong, improving moldability.

[0041] Furthermore, functional layers such as a primer layer, hard coat layer, abrasion-resistant layer, scratch-resistant layer, anti-reflective layer, color correction layer, ultraviolet absorption layer, light-stabilizing layer, heat-absorbing layer, printing layer, gas barrier layer, and adhesive layer may be formed on at least one surface of the multilayer laminated film. These layers may be single-layer or multilayer in structure, and one layer may have multiple functions. In addition, the multilayer laminated film may contain additives such as ultraviolet absorbers, light stabilizers (HALS), heat-absorbing agents, crystal nucleating agents, and plasticizers. These components can be used in combination as long as they do not impair the effects of the present invention, and can be used in any layer.

[0042] The multilayer laminated film of the present invention has a structure in which layers made of a first thermoplastic resin (layer A) and layers made of a second thermoplastic resin (layer B) are alternately laminated, wherein the first thermoplastic resin is mainly composed of crystalline polyester, and layer B is mainly composed of amorphous polyester or crystalline polyester having a melting point 5°C to 100°C lower than that of the thermoplastic resin constituting layer A. By adopting this configuration, the in-plane refractive index difference between layer A and layer B can be increased, and as a result, the reflectivity of the multilayer laminated film can be increased. The method for measuring the in-plane refractive index of each layer is shown in the examples.

[0043] Examples of thermoplastic resins that can be used in the multilayer laminated film of the present invention include chain-like polyolefins such as polyethylene, polypropylene, poly(4-methylpentene-1), and polyacetal; alicyclic polyolefins which are ring-opening metathesis polymers, addition polymers, and addition copolymers with other olefins of norbornene; biodegradable polymers such as polylactic acid and polybutyl succinate; polyamides such as nylon 6, nylon 11, nylon 12, and nylon 66; aramids; polymethyl methacrylate; polyvinyl chloride; polyvinylidene chloride; polyvinyl alcohol; polyvinyl butyral; and ethylene vinyl acetate copolymer. Examples include polyesters such as polyacetal, polyglycolic acid, polystyrene, styrene copolymer polymethyl methacrylate, polycarbonate, polypropylene terephthalate, polyethylene terephthalate, polybutylene terephthalate, and polyethylene-2,6-naphthalate, as well as polyethersulfone, polyetheretherketone, modified polyphenylene ether, polyphenylene sulfide, polyetherimide, polyimide, polyarylate, tetrafluoroethylene resin, trifluoroethylene resin, trifluoroethylene chloride resin, tetrafluoroethylene-hexafluoropropylene copolymer, and polyvinylidene fluoride. Among these, polyester is particularly preferred from the viewpoint of strength, heat resistance, transparency, and versatility. These may be copolymers or mixtures of two or more resins.

[0044] Polyester refers to a resin having a molecular structure in which dicarboxylic acid units and diol units are linked by ester bonds. Preferred polyesters are those obtained by polymerization from monomers mainly composed of aromatic dicarboxylic acids or aliphatic dicarboxylic acids and diols. Examples of aromatic dicarboxylic acids include terephthalic acid, isophthalic acid, phthalic acid, 1,4-naphthalenedicarboxylic acid, 1,5-naphthalenedicarboxylic acid, 2,6-naphthalenedicarboxylic acid, 4,4′-diphenyldicarboxylic acid, 4,4′-diphenyletherdicarboxylic acid, and 4,4′-diphenylsulfondicarboxylic acid. Examples of aliphatic dicarboxylic acids include adipic acid, suberic acid, sebacic acid, dimer acid, dodecanedionic acid, cyclohexanedicarboxylic acid, and their ester derivatives. Among these, terephthalic acid and 2,6-naphthalenedicarboxylic acid, which exhibit high refractive indices, are preferred. These acid components may be used individually, in combination of two or more, or partially copolymerized with oxyacids such as hydroxybenzoic acid.

[0045] Examples of diol components include ethylene glycol, 1,2-propanediol, 1,3-propanediol, neopentyl glycol, 1,3-butanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,2-cyclohexanedimethanol, 1,3-cyclohexanedimethanol, 1,4-cyclohexanedimethanol, diethylene glycol, triethylene glycol, polyalkylene glycol, 2,2-bis(4-hydroxyethoxyphenyl)propane, isosorbate, and spiroglycol. Among these, ethylene glycol is preferred. These diol components may be used individually or in combination of two or more.

[0046] The thermoplastic resin that forms the main component of each layer of the multilayer laminated film of the present invention is preferably selected from among the polyesters mentioned above, such as polyethylene terephthalate and its polymer, polyethylene naphthalate and its copolymer, polybutylene terephthalate and its copolymer, polybutylene naphthalate and its copolymer, and further, polyhexamethylene terephthalate and its copolymer, and polyhexamethylene naphthalate and its copolymer.

[0047] A preferred combination of thermoplastic resins that form the main components of each layer (first thermoplastic resin, second thermoplastic resin) of the multilayer laminated film of the present invention is a combination having the same basic skeleton. The basic skeleton, as used here, refers to the repeating unit that constitutes the thermoplastic resin and is present in the largest quantity. For example, if the thermoplastic resin is polyethylene terephthalate, then its basic skeleton is the ethylene terephthalate skeleton.

[0048] For example, when polyethylene terephthalate is used as one of the thermoplastic resins, it is preferable that the other thermoplastic resin contains an ethylene terephthalate skeleton, which is the same basic skeleton as polyethylene terephthalate, from the viewpoint of easily achieving a high-precision laminated structure. When thermoplastic resins with different optical properties contain the same basic skeleton, the lamination accuracy is increased, and delamination at the lamination interface is also less likely to occur. As a method for measuring the SP value, a turbidity titration method can be used, in which a poor solvent is added to the resin solution and the point at which it becomes cloudy is titrated.

[0049] Furthermore, various additives, such as antioxidants, heat stabilizers, weather stabilizers, ultraviolet absorbers, organic lubricants, pigments, dyes, organic or inorganic fine particles, fillers, antistatic agents, and nucleating agents, may be added to the thermoplastic resin, either individually or in combination, to the extent that they do not impair its properties. These components may be added to either the first thermoplastic resin, the second thermoplastic resin, or both, as long as they do not impair the effects of the present invention.

[0050] The multilayer laminated film of the present invention preferably has a reflectance peak over a continuous range of 5 nm or more in the wavelength range of 240 nm to 2600 nm, where the reflectance is 30% to 100%. In the multilayer laminated film of the present invention, the above requirement is satisfied if even one such reflectance peak exists. The number of reflectance peaks is determined by the number of bands where the reflectance is 30% to 100% continuously.

[0051] Generally, the reflection wavelength of a multilayer laminated film is determined by equation (A) above. Therefore, the bandwidth and width (reflection band) of the reflection peak of a multilayer laminated film can be adjusted by designing the layer thickness of adjacent layers A and B based on equation (A). Furthermore, the reflectance at the reflection peak increases as the in-plane refractive index difference between layers A and B increases, and as the number of layers increases. For this reason, the reflectance at the reflection peak can be adjusted by designing the in-plane refractive index difference between layers A and B and the number of layers to achieve the desired reflectance.

[0052] Examples of multilayer laminated films with such reflective properties include near-infrared reflective films that reflect wavelengths of 850nm to 1150nm, dichroic films that reflect red (600nm to 700nm), green (500nm to 570nm), and blue (430nm to 480nm), respectively, and ultraviolet reflective films that reflect wavelengths of 300nm to 400nm. By using the multilayer laminated film of the present invention with such reflective properties, the reflective properties become more uniform over a wide range from the center to the edges in the width direction, thereby improving the yield of product width and the uniformity of quality.

[0053] The multilayer laminated film of the present invention preferably has an average reflectance in the range of 400 nm to 800 nm wavelength of 20% or more and 100% or less. Examples of the multilayer laminated film having such reflection characteristics include metallic films such as half mirrors and mirrors that transmit or 100% reflect light with a wavelength of 400 nm to 800 nm. By making the multilayer laminated film of the present invention have such reflection characteristics, the reflection characteristics become more uniform over a wide range from the central position to the end position in the width direction, so that the product width yield and the quality uniformity can be improved. Since the reflection wavelength of the multilayer laminated film is determined by the above-mentioned formula (A), the average reflectance can be achieved by designing the layer thicknesses of adjacent layers A and B to reflect the range of 400 nm to 800 nm wavelength based on the formula (A).

[0054] The multilayer laminated film of the present invention has a transmittance of visible light incident perpendicularly to the multilayer laminated film surface of 50% or more and 100% or less, and when the reflectance (%) of each P wave when visible light is incident at angles of 20°, 40°, and 60° with respect to the normal of the multilayer laminated film surface is Rp20, Rp40, and Rp60, respectively, it satisfies the relationship Rp20 ≦ Rp40 < Rp60, and Rp60 is preferably 10% or more and 100% or less. By having such optical characteristics, light from the front direction of the film surface is transmitted and light from the oblique direction is reflected. Therefore, such a multilayer laminated film can be used as a projection member for devices that project images from an oblique direction, such as an extended reality device or a head-up display.

[0055] Here, "the transmittance of visible light incident perpendicularly to the multilayer laminated film surface is 80% or more and 100% or less" specifically means that the average transmittance of light with a wavelength of 400 to 700 nm incident perpendicularly to the multilayer laminated film surface is 80% or more and 100% or less. Because of this high transmittance of light covering most of the visible light spectrum (400 to 700 nm), the film possesses transparency similar to transparent glass or transparent resin film, and when observing the background through the multilayer laminated film from a direction perpendicular to the film surface, good visibility of the background can be obtained. If the transmittance is 80% or higher, the user can see the background without noticing the presence of the multilayer laminated film. From the viewpoint of ease of implementation, the upper limit of this transmittance is preferably 99%.

[0056] The transmittance of light incident perpendicularly to the surface of a multilayer laminated film can be measured by measuring the transmittance of light with wavelengths of 400 to 700 nm at an incident angle θ = 0° in 1 nm increments using a spectrophotometer and calculating the average value (detailed measurement conditions will be described later). Such a multilayer laminated film can be obtained by reducing the difference in refractive index in the direction parallel to the film surface between two alternately laminated thermoplastic resin layers (in-plane refractive index difference; details of the measurement method will be described later). If the difference in refractive index in the direction parallel to the film surface is 0.02 or less, it becomes easy to achieve a transmittance of 80% or more. Note that "difference in refractive index in the direction parallel to the film surface" refers to the absolute value of the difference in in-plane refractive index between two types of thermoplastic resin layers (if the two types of layers are called layer A and layer B, it is the difference in in-plane refractive index between layer A and layer B).

[0057] Rp20, Rp40, and Rp60 are the average reflectance of P waves in the wavelength range of 400 to 700 nm. The reflectance (%) of these P waves can be measured by using a spectrophotometer to measure the reflectance of P waves in the wavelength range of 400 to 700 nm at incident angles θ = 20°, 40°, and 60° in 1-nm increments and calculating the average value (detailed measurement conditions will be described later). Note that the P wave and S wave can be defined as follows. When electromagnetic waves (light) are incident obliquely from the front surface of an object, the P wave is an electromagnetic wave whose electric field component is parallel to the incident plane (linearly polarized light vibrating parallel to the incident plane), and the S wave is an electromagnetic wave whose electric field component is perpendicular to the incident plane (linearly polarized light vibrating perpendicular to the incident plane).

[0058] In order to obtain a multilayer laminated film that satisfies the relationship Rp20 ≤ Rp40 < Rp60 and Rp60 is 10% or more, a method of adjusting the refractive index difference and the number of layers in the direction perpendicular to the film surface between two thermoplastic resin layers can be used. At this time, the larger the refractive index difference in the direction perpendicular to the film surface and the larger the number of layers, the larger Rp60 can be. For example, when the number of layers reaches 401 layers, if the refractive index difference in the direction perpendicular to the film surface is 0.08 or more, the reflectance can be easily increased to 20% or more, and if the refractive index difference is 0.12 or more, the reflectance can be easily increased to 35% or more. Also, even if the refractive index difference does not reach the above level, the reflectance can be increased to reach the above level by further increasing the number of layers.

[0059] The multilayer laminated film of the present invention preferably has a P-wave chroma of 0 to 20 when incident at an angle of 60° with respect to the normal of the multilayer laminated film, more preferably 0 to 8, and even more preferably 0 to 5. Hereinafter, "the chroma of the P-wave reflected light when incident at an angle of 60° with respect to the normal of the multilayer laminated film surface" may be referred to as "the chroma of the P-wave reflected light." A P-wave chroma of 20 or less means that uniform reflection can be achieved across the entire wavelength range of visible light, and by adopting this configuration, coloring caused by reflected light can be suppressed. Therefore, when the multilayer laminated film is used as a projection member in an augmented reality device or a head-up display, the color of the projected image displayed when the projected image is projected with P-waves is reproduced as almost the same color as the image irradiated from the display.

[0060] An example of a method for reducing the saturation of reflected P-wave light to 20 or less will be explained using Figure 5. According to equation (A) above, by uniformly arranging the thicknesses of layer A and layer B that reflect wavelengths in the range of 400 nm to 700 nm, as shown in Figure 5, the standard deviation of the reflectance in that wavelength band can be reduced to 10% or less. Here, Figure 5 shows an example of an ideal layer thickness distribution of layer A and layer B in a multilayer laminated film with 401 layers, where the perpendicular refractive index (nA) of layer A is 1.5 and the perpendicular refractive index (nB) of layer B is 1.6, and the position of the layer on the film surface is 1, up to the position of the layer on the opposite film surface, 401. In reality, factors such as the design accuracy of the equipment and the operational stability of the film manufacturing equipment can cause errors from the ideal layer thickness as shown in Figure 5. However, if the average error across all layers from layer 1 to layer 401 is within approximately ±10%, the chromin of the reflected P-wave when incident at a 60° angle to the normal of the multilayer laminated film can be reduced to 20 or less.

[0061] Here, as a method for suppressing thickness errors, we will explain using a configuration in which two types of thermoplastic resin layers are alternately laminated as an example. A multilayer laminated structure can be obtained by melting each of the two types of thermoplastic resins, alternately laminating them using a lamination device, and then melt-extruding the molten laminate into a sheet using a T-type die or the like. Suppressing the disorder of the layers in this molten laminate leads to suppressing thickness errors. One method for doing this is to provide a thick layer on the outermost layer of the molten laminate. The thickness of this outermost layer is preferably 1% or more of the total thickness of the molten laminate, and more preferably 4% or more. Furthermore, it is even more preferable to make both outermost layers thicker, rather than just one.

[0062] The multilayer laminated film of the present invention preferably has an Rp60 orientation angle variation of 0.1% or more and 10% or less. Here, the orientation angle refers to each of the orientation angles (0°, 45°, 90°, 135°, 180°) when the orientation angle in the main orientation axis direction of the multilayer laminated film 3 constituting the laminate of the present invention is set to 0°, as shown in Figure 6, and the main orientation axis direction refers to the direction with the greatest degree of orientation within the film plane. The degree of orientation can be measured by a known molecular orientation meter, and as a molecular orientation meter, for example, the molecular orientation meter MOA-7015 from Oji Instruments Co., Ltd. can be used. The orientation angle variation refers to the difference between the maximum and minimum values ​​of Rp60(0°), Rp60(45°), Rp60(90°), Rp60(135°), and Rp60(180°) measured at the above orientation angles (0°, 45°, 90°, 135°, 180°).

[0063] Rp60(0°), Rp60(45°), Rp60(90°), Rp60(135°), and Rp60(180°) can be measured by measuring the reflectance of P-waves with wavelengths of 400-700 nm at an incident angle θ=60° in 1 nm increments using a spectrophotometer and calculating the average value. Here, the azimuth angle, which is the tilt direction, is set to 0° with respect to the azimuth angle in the main orientation axis direction of the multilayer laminated film, and five angles are adopted clockwise from this reference: 0°, 45°, 90°, 135°, and 180°. If the azimuth angle variation of Rp60 is 10% or less, preferably 5% or less, the display quality, such as the brightness of the information, can be maintained at the same level regardless of the direction from which the image is projected.

[0064] To reduce the azimuthal angle variation of Rp60, for example, the refractive index unevenness in the in-plane direction of the laminated film of the present invention can be reduced. To reduce the refractive index unevenness in the in-plane direction of the film, the film should be stretched in such a way that the difference in orientation between the longitudinal and width directions of the film is reduced during biaxial stretching. The stretching conditions that reduce the difference in orientation between the longitudinal and width directions vary depending on the thermoplastic resin used and its combination, but when using polyester resin, for example, a condition in which the stretching ratio in the width direction is slightly higher than that in the longitudinal direction is a preferred example. This effect is one of the features of the multilayer laminated film of the present invention and is an effect that cannot be achieved with known polarizing reflective films.

[0065] The multilayer laminated film of the present invention can take the form of a multilayer laminated film roll, which is formed by winding the multilayer laminated film onto a core. From the viewpoint of improving the productivity of molded exterior parts for smartphones, tablets, etc., and its application to window components, the multilayer laminated film roll of the present invention preferably has a width of 1 m or more and a length of 100 m or more. Here, width refers to the length in the width direction, and length refers to the length in the longitudinal direction.

[0066] The following describes a molded article using the multilayer laminated film of the present invention. The molded article using the multilayer laminated film of the present invention uses the multilayer laminated film of the present invention or a roll of the multilayer laminated film of the present invention. More specifically, a molded article has a structure in which a support is laminated on at least one side thereof to the multilayer laminated film. Examples of support materials include glass and resin, and preferred resins include polyethylene terephthalate, polycarbonate, acrylic, polyvinyl chloride, polyethylene, polypropylene, polymethylpentene and its copolymers, and acrylonitrile-butadiene-styrene copolymer. Furthermore, methods for laminating the multilayer laminated film and the support include bonding by forming an adhesive layer using adhesives or other adhesives. Examples of adhesives and adhesives include vinyl acetate resins, vinyl chloride / vinyl acetate copolymers, ethylene / vinyl acetate copolymers, polyvinyl alcohol, polyvinyl butyral, polyvinyl acetal, polyvinyl ether, nitrile rubbers, styrene / butadiene rubbers, natural rubbers, chloroprene rubbers, polyamides, epoxy resins, polyurethanes, acrylic resins, celluloses, polyvinyl chloride, polyacrylic acid esters, and polyisobutylene.

[0067] Furthermore, these adhesives and bonding agents may contain tackiness modifiers, plasticizers, heat stabilizers, antioxidants, UV absorbers, antistatic agents, lubricants, colorants, crosslinking agents, etc. The pre-processing forms of these adhesives include liquid, gel, lump, powder, and film. Methods for solidifying the adhesive layer include solvent evaporation, moisture curing, heat curing, curing agent mixing, anaerobic curing, UV curing, thermal melting and cooling, and pressure sensitivity. Lamination methods include lamination molding and injection molding, and the molded body is produced by heating, pressurizing, and the aforementioned adhesive layer solidification methods. The support may be transparent or colored, but it is preferable that it be transparent when the molded body of the present invention is used as a projection member for augmented reality or the like. Applications of the molded body of the present invention include decorative applications, display applications, heat shielding applications, and augmented reality device applications.

[0068] Next, an augmented reality device using the molded body of the present invention will be described. The augmented reality device is an augmented reality device that comprises the molded body of the present invention and an image projection device that irradiates light onto its display surface. Its forms of use include being worn on the head or projecting images onto the windows of transportation vehicles, etc. (head-up display). Specifically, the form worn on the head includes a glasses-type form.

[0069] The following describes in detail an example of a method for manufacturing the multilayer laminated film of the present invention, but the multilayer laminated film of the present invention is not limited to this example.

[0070] When the multilayer laminated film of the present invention has the multilayer laminated film configuration described above, a laminated structure of 51 or more layers can be manufactured by the following method. First, the first thermoplastic resin and the second thermoplastic resin are supplied in a molten state from two extruders, Extruder A corresponding to layer A and Extruder B corresponding to layer B. The molten thermoplastic resins from each flow path are laminated in 51 or more layers using a multi-manifold type feed block or a comb type feed block, which are known lamination devices, so that the first thermoplastic resin becomes the resurface layer on both sides. Next, the molten laminate is extruded into a sheet shape using a T-type die or the like, and cooled and solidified on a casting drum to obtain an unstretched multilayer laminated film. As a method for improving the lamination accuracy of layers A and B, the methods described in Japanese Patent Publication No. 2007-307893, Japanese Patent No. 4691910, and Japanese Patent No. 4816419 are preferred. At this time, the slit width, slit gap, and slit length of the lamination device can be adjusted according to the desired layer group configuration. Furthermore, if necessary, it is preferable to dry the first thermoplastic resin used in layer A and the first thermoplastic resin used in layer B.

[0071] Next, the unstretched multilayer laminated film is subjected to stretching and heat treatment. The known sequential biaxial stretching method or simultaneous biaxial stretching method is preferred as the stretching method. The stretching temperature is preferably in the range of above the glass transition temperature of the unstretched laminated film to below the glass transition temperature + 80°C. The stretching ratio is preferably in the range of 2 to 8 times in both the longitudinal and width directions, more preferably in the range of 3 to 6 times, with a small difference in stretching ratio between the longitudinal and width directions, or a condition where the stretching ratio in the width direction is slightly higher than that in the longitudinal direction. Longitudinal stretching is preferably performed using the difference in peripheral speed between the rolls of the longitudinal stretcher. Furthermore, the known tenter method is preferred for subsequent widthwise stretching. That is, the uniaxially oriented multilayer laminated film can be stretched in the width direction by conveying it while gripping both widthwise ends with clips and widening the distance between opposing clips in the width direction.

[0072] Furthermore, simultaneous biaxial stretching using a tenter is also preferable. The case of simultaneous biaxial stretching will be described below. The unstretched laminated film cast on the casting drum is guided to a simultaneous biaxial tenter, and while gripping both ends in the width direction with clips, it is transported and stretched simultaneously and / or in stages in the longitudinal and width directions. Longitudinal stretching is achieved by widening the distance between clips on the same side, and widthwise stretching is achieved by widening the spacing between opposing clips by widening the spacing of the rails on which the clips run. In this invention, the tenter clips subjected to stretching and heat treatment are preferably driven by a linear motor system. Other systems include a pantograph system and a screw system, but among them, the linear motor system is superior in that the stretching ratio can be freely changed because of the high degree of freedom of each clip. The preferred stretching temperature and ratio are the same as in the case of sequential biaxial stretching.

[0073] Furthermore, it is preferable to perform heat treatment after stretching. The heat treatment temperature is preferably in the range of above the stretching temperature in the width direction and below the melting point of the thermoplastic resin of layer A, and it is also preferable to perform a cooling step at a temperature of -30°C or lower after the heat treatment. In addition, in order to reduce the thermal shrinkage rate of the multilayer laminated film, it is also preferable to shrink (relax) the film in the width direction and / or in the longitudinal direction during the heat treatment step or the cooling step. The relaxation rate is preferably in the range of 1% to 10%, and more preferably in the range of 1% to 5%. Finally, the multilayer laminated film and multilayer laminated film roll of the present invention are manufactured by winding the film with a winding machine. [Examples]

[0074] The multilayer laminated film of the present invention will be described in more detail below using examples. However, the multilayer laminated film of the present invention is not limited to these examples.

[0075] [Methods for measuring physical properties and evaluating their effects] The evaluation methods for characteristic values ​​and effects are as follows. Of the evaluation items described below, items (2) to (7) and (9) were measured for a film sample with a film width of 1.1 m at the center and edge positions (0.5 m from the center towards the edge) in the width direction. Measurements at the edge positions were performed only on one side (the left edge when viewed from the direction of film travel).

[0076] (1) Number of layers and surface thickness of multilayer laminated film The number of layers and the thickness of the surface layer of multilayer laminated films were confirmed by observing samples obtained by cross-section using a microtome with a transmission electron microscope (TEM). Cross-sectional images were taken using a Hitachi H-7100FA transmission electron microscope under an acceleration voltage of 75 kV. The thickness of the surface layer was measured using the microscope's length-measuring function.

[0077] (2) Layer thickness and gradient structure of layer group La, Lb, Lc, Ld, Le (1) The TEM images obtained in section (1) were opened using the image processing software Image-Pro Plus ver.4, and image analysis was performed. In the image analysis process, the relationship between the position in the thickness direction and the average brightness of the region between two lines in the width direction was read as numerical data in vertical thick profile mode. Using the spreadsheet software "Excel" (registered trademark) (Microsoft Office 365), a 5-point moving average numerical processing was applied to the position (nm) and brightness data. Furthermore, the obtained data with periodically changing brightness was differentiated, and the maximum and minimum values ​​of the differential curve were read using a VBA (Visual Basic for Applications) program, and the layer thickness was calculated by taking the interval between these adjacent values ​​as the layer thickness of one layer. This operation was performed for each image to calculate the layer thickness of all layers. For the calculated layer thickness, when the multilayer laminated film was divided in half so that the thickness was equal, the surface with more layers was designated as Surface 1, and the surface with fewer layers was designated as Surface 2. For the section from surface 1 to surface 2, the layers La, Lb, Lc, Ld, and Le were defined as follows. Here, the section indicates the thickness position (%) of the layer from surface 1. Stratum La: Stratum located in the range of 15% to 30% Stratum Lb: Stratum located in the range of 75% to 85% Stratum Lc: Stratum located in the range of 30% to 75% Layer group Ld: A layer group located in the section from surface 1 to the starting point of layer group La. Layer group Le: A layer group located in the section from the endpoint of layer group Lb to surface 2. For the above-mentioned layer group, the following items were measured or calculated. For each layer, the layer thickness was determined using the method shown in Figure 2. The average layer thickness of adjacent layers A and B on the surface 1 side was calculated, and this average layer thickness was used as the layer thickness for layers A and B. Layer group La: The proportion of layers with a thickness in the bottom 10% (labeled as Layer Group La Percentage in Table 2). Layer group Lb: The percentage of layers with a thickness in the top 10% (labeled as Layer Group Lb Percentage in Table 2). Layer group Lc: The horizontal axis represents the thickness position (%) of the layer from surface 1, and the vertical axis represents the average layer thickness (nm) of adjacent layers A and B. The slope of the linear approximation equation is defined as XLc, and XLab is defined as (average layer thickness of layer group La - average layer thickness of layer group Lb) (nm) / (75 - 30) (%). Layer group Ld: Presence or absence of a sloping structure, and maximum layer thickness. Layer group Le: Presence or absence of a gradient structure, minimum layer thickness.

[0078] (3) Reflectance of a reflectance peak that is between 30% and 100% and its wavelength range The reflectance of a Hitachi U-4100 Spectrophotometer (solid-state measurement system) was measured in 1nm increments at an incident angle θ=12° for wavelengths from 240 to 2600 nm. Measurement conditions: The slit was set to 2 nm (visible) / automatic control (infrared), the gain was set to 2, and the scanning speed was set to 600 nm / min. From the obtained reflectance data, the reflectance and its wavelength range were determined for the reflectance peaks with reflectance between 30% and 100%.

[0079] (4) Average reflectance in the wavelength range of 400 nm to 800 nm The reflectance was measured using the same method as in section (3), and the average reflectance in the wavelength range of 400 nm to 800 nm was determined from the obtained reflectance data.

[0080] (5) Transmittance of visible light of multilayer laminated film Using a Hitachi, Ltd. U-4100 Spectrophotometer in its standard configuration (solid-state measurement system), the transmittance at wavelengths of 400-700 nm at an incident angle θ=0° was measured in 1 nm increments. The average transmittance was calculated, and the resulting value was defined as the visible light transmittance of the multilayer laminated film. Measurement conditions: The slit was set to 2 nm (visible) / automatic control (infrared), the gain was set to 2, and the scanning speed was set to 600 nm / min.

[0081] (6) Reflectance of multilayer laminated films (Rp20, Rp40, Rp60), and chromin of reflected P-wave incident at 60°. An angle-variable reflection unit and a Glan-Taylor polarizer attached to a spectrophotometer (U-4100 Spectrophotomater) manufactured by Hitachi, Ltd. were used to measure the reflectance of P waves in the wavelength range of 240 to 2600 nm at incident angles θ = 20°, 40°, and 60° at 1-nm intervals. From the obtained reflectances, Rp20, Rp40, and Rp60 were determined as the average reflectances of P waves in the wavelength range of 400 nm to 700 nm at incident angles of 20°, 40°, and 60°, respectively. The tilt direction of each incident angle was set to the direction along the main orientation axis of the film. The chroma of the reflected light of the P wave incident at 60° was calculated using the reflectance spectrum of the P wave at θ = 60°, the spectral distribution of the C light source, and the color-matching functions of the XYZ system under the C light source, and the XYZ values, and the chroma C * a * b * Among them, a * and b * were calculated for the P wave at θ = 60° using the reflectance spectrum of the P wave, the spectral distribution of the C light source, and the color-matching functions of the XYZ system under the C light source, and the XYZ values, and the chroma C * value was calculated as the square root of the sum of the squares of a * and b * .

[0082] (7) Rp60(0°), Rp60(45°), Rp60(90°), Rp60(135°), Rp60(180°), azimuth variation An angle-variable reflection unit and a Glan-Taylor polarizer attached to a spectrophotometer (U-4100 Spectrophotomater) manufactured by Hitachi, Ltd. were used to measure the reflectance of P waves in the wavelength range of 400 to 700 nm at an incident angle θ = 60° at 1-nm intervals for each of the five azimuth directions of 0°, 45°, 90°, 135°, and 180° clockwise with respect to the azimuth of 0° in the direction of the main orientation axis of the film surface. From the obtained reflectances, Rp60(0°), Rp60(45°), Rp60(90°), Rp60(135°), and Rp60(180°) were determined as the average reflectances of P waves in the wavelength range of 400 nm to 700 nm at an incident angle of 60° for each azimuth direction. Furthermore, the difference between the maximum value and the minimum value of the obtained Rp60(0°), Rp60(45°), Rp60(90°), Rp60(135°), and Rp60(180°) was taken as the azimuth variation.

[0083] (8) Main orientation axis direction The sample size was set to 10 cm x 10 cm, and the sample was cut at the center in the width direction. The degree of orientation was measured using a molecular orientation analyzer MOA-7015 manufactured by Oji Instruments Co., Ltd., and the direction with the greatest degree of orientation was designated as the principal orientation axis.

[0084] (9) The difference in reflectance between the central position and the edge positions in the width direction, and the wavelength at the edge and in the reflection bandwidth. For the reflectance obtained in item (3) or (4), or the reflectance of the P wave at an incident angle of 60° obtained in item (6), in the reflection band where the reflectance is 30% or more, the wavelength at which the half value of the maximum reflectance in that reflection band is found at the lowest wavelength was defined as the low-wavelength edge wavelength, and the wavelength at which the half value is found at the longest wavelength was defined as the long-wavelength edge wavelength. Furthermore, the deviation of the reflectance in the reflection band (from the low-wavelength edge wavelength to the long-wavelength edge wavelength) was determined.

[0085] (10) Glass transition temperature and melting point of resin A 5 mg sample of multilayer laminated film or resin pellet was weighed using an electronic balance, placed between aluminum pans, and measured using a Seiko Instruments DSC-RDC220 differential scanning calorimeter, following JIS-K-7122 (2012) standards, with the temperature increasing from 25°C to 300°C at a rate of 20°C / min. Data analysis was performed using Seiko Instruments' SSC / 5200 disk session. The glass transition temperature (Tg) and melting point (Tm) were determined from the obtained DSC data.

[0086] (11) Refractive index of resin Using a sodium D line (wavelength 589 nm) as the light source and methylene iodide as the mounting solution, the refractive index of the resin pellets was measured using an Abbe refractometer at 25°C. To measure the refractive index of the resin pellets, resin pellets that had been vacuum-dried at 70°C for 48 hours were melted at 280°C, pressed using a press machine, and then rapidly cooled to produce a 200 μm thick sheet, and the refractive index of that sheet was measured.

[0087] (12) Method for measuring IV (intrinsic viscosity) The viscosity was calculated from the solution viscosity measured using an Ostwald viscometer at 25°C after dissolving the solution at 100°C for 20 minutes with orthochlorophenol as the solvent.

[0088] (13) Refractive index of layer A of a multilayer laminated film The refractive index of the outermost layer of a multilayer laminated film was measured using a SPA-400 prism coupler manufactured by Cylon Technology. The wavelength of the laser used for the measurement was 633 nm. For the in-plane refractive index, the average value obtained from both the outermost layer and the direction perpendicular to the principal orientation axis was calculated. For the perpendicular refractive index, the average value obtained from both the outermost layer and the direction perpendicular to the principal orientation axis was calculated.

[0089] (14) Refractive index of layer B of a multilayer laminated film Since layer B is an internal layer of a multilayer laminated film, the refractive index was measured on a film of layer B resin alone, which was prepared under the same stretching and heat treatment conditions as the multilayer laminated film, using a Sylon Technology SPA-400 prism coupler. The wavelength of the laser used for measurement was 633 nm. For the in-plane refractive index, the average value of the values ​​obtained on both sides of the film was calculated in both the direction along the principal orientation axis and the direction perpendicular to the principal orientation axis. For the perpendicular refractive index, the average value of the values ​​measured from the side along the principal orientation axis and the side perpendicular to the principal orientation axis was calculated on both sides of the film.

[0090] (15) Verification of the refractive index of the B layer of a multilayer laminated film An optical simulation of reflectivity was performed using the layer thickness of the multilayer laminated film obtained in section (2), the refractive index of layer A of the multilayer laminated film obtained in section (13), and the refractive index of layer B obtained in section (14). The results of this optical simulation were compared with the reflectivity measured in section (6), and if the difference between the two was less than or equal to ±3%, the refractive index of layer B obtained in section (14) was considered to be the refractive index of layer B of the multilayer laminated film. The optical simulation was calculated using a VBA program with the optical thin film characteristic matrix method (Mitsunobu Kohiyama (2006). Optical thin film filter design. Optronics Co., Ltd.).

[0091] [Thermoplastic resin used in the film] The following resins were used to manufacture the films used in each example and comparative example. These are all thermoplastic resins; resins A, C, E, and F are crystalline resins, while resins B and D are amorphous resins. Resin A: Polyethylene terephthalate with IV=0.65, refractive index=1.58, Tg=78℃, Tm=254℃. Resin B: A copolymer of polyethylene terephthalate with IV=0.72 (polyethylene terephthalate copolymerized with 20 mol% cyclohexanedicarboxylic acid relative to the total acid component and 20 mol% spiroglycol relative to the total diol component), refractive index=1.55, Tg76=℃, Tm was not observed. Polymer of polyethylene naphthalate with resin C:IV=0.64 (polyethylene naphthalate copolymerized with polyethylene glycol of molecular weight 400 at 4 mol% relative to the total diol component), refractive index=1.64, Tg=103℃, Tm=258℃ The resin D: IV = 0.73 polyethylene terephthalate copolymer (polyethylene terephthalate copolymerized with 33 mol% cyclohexanedimethanol relative to the total diol component), refractive index = 1.57, Tg = 80°C, and Tm was not observed. Resin E: A copolymer of polyethylene naphthalate with IV=0.64 (polyethylene naphthalate copolymerized with 20 mol% terephthalic acid relative to the total acid component and 5 mol% polyethylene glycol with a molecular weight of 400 relative to the total diol component), refractive index=1.63, Tg=85℃, Tm=215℃. The resin F:IV=0.67 polyethylene terephthalate copolymer (polyethylene naphthalate copolymerized with 20 mol% naphthalened dicarboxylic acid relative to the total acid component), refractive index=1.59, Tg=89℃, Tm=210℃.

[0092] Below, multilayer laminated films were prepared according to each example and comparative example, and the conditions and evaluation results are shown in Tables 1 to 4. Furthermore, the design of the layer thickness at the center position in the width direction of the multilayer laminated films prepared in each example and comparative example is shown in Figures 7 to 11. The layer thicknesses shown in Figures 7 to 11 represent the average layer thickness (nm) of adjacent layers A and B at the layer thickness position (%) from surface 1 of the multilayer laminated film, from surface 1 to surface 2.

[0093] (Example 1) Resin A was used as the thermoplastic resin constituting layer A (first thermoplastic resin), and resin B was used as the thermoplastic resin constituting layer B (second thermoplastic resin). Resin A and resin B were melted at 280°C in an extruder, passed through five FSS-type leaf disc filters, and then, while being metered with a gear pump so that the discharge ratio (layering ratio) was resin A / resin B = 1.2, they were alternately merged in a 201-layer feed block (101 layers of layer A and 100 layers of layer B) designed to achieve the design layer thickness shown in Figure 7-A, so that both surface layers were resin A. Next, the resulting laminate of molten thermoplastic resin was supplied to a T-die and formed into a sheet, which was then extruded from the slit of the T-die. After that, the molten sheet was rapidly cooled and solidified on a casting drum where the surface temperature was maintained at 25°C while applying an electrostatic voltage of 8kV with a wire to obtain an unstretched multilayer laminated film. This unstretched multilayer laminated film was longitudinally stretched at a temperature of 90°C and a stretching ratio of 3.3 times. Corona discharge treatment was then performed on both sides in air, and then an easy-adhesion layer forming film coating solution consisting of (polyester resin with a glass transition temperature of 18°C) / (polyester resin with a glass transition temperature of 82°C) / silica particles with an average particle size of 100 nm was applied to both sides. The resulting uniaxially oriented multilayer laminated film was then guided to a tenter with both ends in the width direction gripped with clips, transversely stretched at a temperature of 100°C and a stretching ratio of 4.0 times, followed by heat treatment at 230°C and 5% widthwise relaxation, and then cooled to 100°C. After that, both ends of the film, including the clip gripping portions, were slit and removed, and the film was wound into a roll with a film width of 1.1 m to obtain a multilayer laminated film with a thickness of 20 μm (thickness of both surface layers: 1.1 μm). The confluence using a feed block was performed using one slit plate as described in Japanese Patent Publication No. 2007-307893, Japanese Patent No. 4691910, and Japanese Patent No. 4816419. Specifically, after confluence, the combined fluid (a molten laminated flow in which layers A and B are alternately stacked 201 times) flowed towards the T-die through a rectangular pipe connected downstream of the feed block, and the combined fluid was widened in the width direction at the T-die connected downstream of the rectangular pipe before being discharged to the casting drum. The evaluation results of the obtained multilayer laminated film are shown in Tables 2 to 4.

[0094] (Examples 2-19, Comparative Examples 1-5) A multilayer laminated film was obtained in the same manner as in Example 1, except that the resin of each layer, the design of the layer thickness at the center in the width direction, the number of layers, the thickness of the surface layer, the overall thickness, the lamination ratio, and the film formation conditions were as shown in Table 1. The evaluation results of the obtained multilayer laminated films are shown in Tables 1 to 4. In all cases, the layer configuration consisted of alternating lamination of layer A and layer B, with layer A being the outermost layer on both sides. The number of layers was adjusted by the number of slits in the laminating apparatus, and the layer configuration was adjusted by the slit width, slit gap, and slit length of the laminating apparatus.

[0095] The design layer thicknesses of Comparative Example 3 (Figure 11-C) and Comparative Example 4 (Figure 11-D) have a similar profile to the design layer thickness of Example 2 (Figure 7-B). However, in Comparative Examples 3 and 4, the layer group La does not include more than 50% of the layers that make up the bottom 10% of the layers with a thickness of 1 nm to 1000 nm that constitute the multilayer laminated film. As a result, the changes at the low wavelength edge at the center of the width direction and at the edges of the width direction are larger compared to Example 2, resulting in poor optical property uniformity.

[0096] (Comparative Example 6) A multilayer laminated film was obtained in the same manner as in Example 1, except that the resin of each layer, the design of the layer thickness at the center in the width direction, the number of layers, the thickness of the surface layer, the overall thickness, the lamination ratio, and the film formation conditions were as shown in Table 1. The design of the layer thickness at the center in the width direction was such that the layer thickness of the 2nd to 9th layers was 100 nm, and the layer thickness of both surface layers was 5 μm. No reflection peaks were generated from the obtained multilayer laminated film. Since no reflection peaks were generated in the film of this comparative example, the evaluation results are not shown in Tables 2 to 4.

[0097] In the design layer thickness at the center in the width direction shown in Table 1 (Figures 7-11), the thickness of the outermost layer on both surface 1 and surface 2 is approximately 5% of the total film thickness and exceeds 1000 nm. Therefore, the outermost layers on both sides are not shown in Figures 7-11. In Examples 5, 10, 15, and 19, the refractive index of layer B of the multilayer laminated film in item (15) was verified, and the difference between the two was always ±3% or less. Therefore, the refractive index of layer B obtained in item (14) was considered to be the refractive index of layer B of the multilayer laminated film.

[0098] [Table 1]

[0099] [Table 2]

[0100] [Table 3]

[0101] [Table 4] [Industrial applicability]

[0102] The present invention provides a multilayer laminated film that can achieve high lamination accuracy as designed over a wide range in the width direction of the film, and therefore has a uniform reflectance spectrum over a wide range in the width direction of the film. The multilayer laminated film of the present invention can be suitably used in molded articles and the like. [Explanation of Symbols]

[0103] 1: Average thickness of layers at the center in the width direction 2: Average thickness of layers at the end positions in the width direction 3: Reflectance spectrum at the center in the width direction 4: Reflectance spectrum at the edge position in the width direction 5: Cross-section of the 1st to 8th layers on the surface 1 side of a multilayer laminated film. 6: Layer A 7: Layer B 8: Multilayer laminated film

Claims

1. A multilayer laminated film in which 51 or more layers of different thermoplastic resins are alternately laminated, When the aforementioned multilayer laminated film is divided in two such that the thicknesses are equal, the surface with more layers is designated as Surface 1, the surface with fewer layers as Surface 2, and the group of layers located in the range of 15% to 30% of the section from Surface 1 to Surface 2 is designated as layer group La. A multilayer laminated film characterized in that the layer group La includes 50% or more of the layers that make up the bottom 10% of the layers with a thickness of 1 nm to 1000 nm that constitute the multilayer laminated film.

2. The multilayer laminated film according to claim 1, wherein when the group of layers located in the range of 75% to 85% of the interval from surface 1 to surface 2 is defined as layer group Lb, layer group Lb includes 70% or more of the layers that make up the top 10% of the thickness of the layers with a thickness of 1 nm to 1000 nm that constitute the multilayer laminated film.

3. The multilayer laminated film according to claim 1 or 2, wherein when the group of layers located in the range of 30% to 75% of the section from surface 1 to surface 2 is called the layer group Lc, the thickness of the layers constituting the layer group Lc has a gradient structure.

4. When the layer group located in the section from surface 1 to the starting point of layer group La is called layer group Ld, and the layer group located in the section from the end point of layer group Lb to surface 2 is called layer group Le, The thickness of the layers constituting the layer group Ld and the layer group Le both have a gradient structure. The average layer thickness of the layer group Ld and the average layer thickness of the layer group Le are both greater than the average layer thickness of the layer group La and less than the average layer thickness of the layer group Lb. The multilayer laminated film according to claim 2, wherein the maximum layer thickness in the layer group Ld is 0.7 times or more the minimum layer thickness in the layer group Le.

5. A multilayer laminated film according to claim 1 or 2, having a structure in which layers made of a first thermoplastic resin (layer A) and layers made of a second thermoplastic resin (layer B) are alternately laminated, wherein the first thermoplastic resin is mainly composed of crystalline polyester, and layer B is mainly composed of amorphous polyester or crystalline polyester having a melting point 5°C to 100°C lower than that of the thermoplastic resin constituting layer A.

6. A multilayer laminated film according to claim 1 or 2, having a reflectance peak in the wavelength range of 240 nm to 2600 nm, where the reflectance is 30% to 100% over a continuous range of 5 nm or more.

7. A multilayer laminated film according to claim 1 or 2, wherein the average reflectance in the wavelength range of 400 nm to 800 nm is 20% or more and 100% or less.

8. A multilayer laminated film according to claim 1 or 2, wherein the transmittance of visible light incident perpendicularly to the multilayer laminated film surface is 80% or more and 100% or less, and when visible light is incident at angles of 20°, 40°, and 60° with respect to the normal to the multilayer laminated film surface, the reflectance (%) of the P-waves is Rp20, Rp40, and Rp60 respectively satisfies the relationship Rp20 ≤ Rp40 < Rp60, and Rp60 is 10% or more and 100% or less.

9. The multilayer laminated film according to claim 1 or 2, wherein the chrominance of the reflected P-wave when incident at an angle of 60° to the normal of the multilayer laminated film is 0 or more and 20 or less.

10. The multilayer laminated film according to claim 8, wherein the azimuthal angle variation of Rp60 is 0.1% or more and 10% or less.

11. A multilayer laminated film roll comprising a multilayer laminated film according to claim 1 or 2 wound onto a core.

12. The multilayer laminated film roll according to claim 11, wherein the width of the multilayer laminated film is 1 m or more and the length is 100 m or more.

13. A molded article using the multilayer laminated film described in claim 1 or 2.

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