Projected image display member

Abstract

To provide a projected image display member that, when used as a projection member of a head-up display or the like, can obtain high display performance of a projected image while suppressing reflection of a surrounding scene other than an image.SOLUTION: A projected image display member is such that the transmittance of visible light incident perpendicularly on a projected image display member surface is 50% or more and 100% or less; the relationship of Rp20≤Rp40<Rp60 is satisfied when the reflectance (%) of a P wave when visible light is incident at angles of 20°, 40°, and 60°to the normal line of the projected image display member surface is Rp20, Rp40, and Rp60, respectively, and Rp60 is 10% or more; and Rs60-Rs20 is 25% or less when the reflectance (%) of an S wave when visible light is incident at angles of 20° and 60°to the normal line of the projected image display member surface is Rs20 and Rs60, respectively.SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to a projection image display member in which the reflection characteristics of S waves and P waves of conventional transparent members are reversed, a projection image display device using said projection image display member, and transportation equipped with said projection image display device. [Background technology]

[0002] In general, transparent glass and transparent resin films have a high transmittance of light from the front direction. For light from an oblique direction, the reflectance of P waves decreases as the angle of incidence increases, reaching 0%, and then increases again, whereas the reflectance of S waves increases as the angle of incidence increases. On the other hand, films have been proposed that have a high transmittance of light from the front direction, and that, for light from an oblique direction, the reflectance of both P waves and S waves increases as the angle of incidence increases (Patent Documents 1 and 2). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Special Publication No. 2006-512622 [Patent Document 2] WO2019 / 198635 publication Summary of the Invention [Problem to be solved by the invention]

[0004] The films disclosed in Patent Documents 1 and 2 have the property that as the incident angle increases, the reflectance of both P-waves and S-waves increases. Therefore, among the two polarizations of P-waves and S-waves, such as glass or transparent resin films, one shows a tendency that as the incident angle increases, the reflectance decreases to 0% and then increases again, while the other shows a tendency that as the incident angle increases, the reflectance also increases. There was a problem that such characteristics could not be realized. Therefore, when the films disclosed in Patent Documents 1 and 2 are used as a projection member such as a head-up display, while high display quality of the projected image can be obtained due to high oblique reflection characteristics, there is also a problem that the reflection of the surrounding scenery other than the image becomes large.

Means for Solving the Problems

[0005] The present invention aims to solve the above problems. That is, the transmittance of visible light incident perpendicularly to the surface of the projection image display member is 50% or more and 100% or less, and when the reflectance (%) of P-waves when visible light is incident at angles of 20°, 40°, and 60° with respect to the normal of the surface of the projection image display member are Rp20, Rp40, and Rp60, respectively, the relationship Rp20 ≦ Rp40 < Rp60 is satisfied, and Rp60 is 10% or more. When the reflectance (%) of S-waves when visible light is incident at angles of 20° and 60° with respect to the normal of the surface of the projection image display member are Rs20 and Rs60, respectively, Rs60 - Rs20 is 25% or less. It is a projection image display member.

[0006] Further, the projection image display member of the present invention can also be in the following aspects, and as shown below, a projection image display device or a transportation device can also be made using this. (1) The transmittance of visible light incident perpendicularly to the surface of the projection image display member is 50% or more and 100% or less. When visible light is incident at angles of 20°, 40°, and 60° with respect to the normal of the surface of the projection image display member, and the reflectance (%) of the P wave is Rp20, Rp40, and Rp60 respectively, the relationship Rp20 ≤ Rp40 < Rp60 is satisfied, and Rp60 is 10% or more. When the reflectance (%) of the S wave is Rs20 and Rs60 respectively when visible light is incident at angles of 20° and 60° with respect to the normal of the surface of the projection image display member, Rs60 - Rs20 is 25% or less. A projection image display member. (2) The projection image display member according to (1), comprising a multilayer laminated film in which a plurality of different thermoplastic resin layers are alternately laminated 51 layers or more. (3) The multilayer laminated film has a structure in which two types of thermoplastic resin layers are alternately laminated. The layer (layer A) made of the first thermoplastic resin contains crystalline polyester as a main component, and the layer (layer B) made of the second thermoplastic resin contains polyester as a main component, and the difference in the in-plane refractive index between the layer A and the layer B is 0.04 or less. The projection image display member according to (2). (4) The projection image display member according to (3), wherein the second thermoplastic resin contains a structure derived from an alkylene glycol having a number average molecular weight of 200 or more. (5) The projection image display member according to any one of (2) to (4), wherein the multilayer laminated film is located on at least one surface of a transparent support. (6) The projection image display member according to any one of (2) to (5), wherein the multilayer laminated film is located between transparent members. (7) The projection image display member according to any one of (1) to (6), wherein the ratio Rp60 / Rs60 of Rp60 to Rs60 is greater than 1.0. (8) The projection image display member according to any one of (2) to (7), wherein 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 20 or less. (9) The projection image display member according to any one of (1) to (8), wherein the azimuth variation of Rp60 is 10% or less. (10) The projection image display member according to any one of (1) to (9), which has at least one low refractive index layer having a refractive index of 1.5 or less on at least one surface of the projection image display member. (11) The projection image display member according to (10), wherein the product n×d of the refractive index n and the layer thickness d of the low refractive index layer is 150 nm or more and 250 nm or less. (12) A projection image display member according to any one of (1) to (11), comprising a concave-convex structure on at least one surface of the projection image display member, the average interval between convex portions and the average height of the convex portions both being within the ranges of 10 nm to 400 nm. (13) A projection image display device comprising: a projection image display member according to any one of (1) to (12) above; and a light source for irradiating light onto the display surface of the projection image display member. (14) The projection image display device according to (13), wherein the intensity of P waves (P wave intensity / (P wave intensity+S wave intensity)) accounts for 51% or more of the intensity of light incident on the display surface of the projection image display member. (15) The projection image display device according to (13) or (14), further comprising a polarization conversion element inside the light source or between the projection image display member and the light source, which converts the orientation of polarized light passing through the light source by 10% or more. (16) The projection image display device according to (15), wherein the polarization conversion element has a phase difference of 100 nm or more at a wavelength of 590 nm. (17) The projection image display device according to (16), wherein the phase difference of the polarization conversion element at a wavelength of 590 nm is 240 nm or more and 320 nm or less, or 100 nm or more and 180 nm or less. (18) A means of transportation comprising the projection image display device according to any one of (13) to (17). Effect of the Invention

[0007] According to the present invention, it is possible to obtain a projection image display component with new optical properties that reverse the S-wave and P-wave reflection properties of conventional transparent components, and a display device that, when used as a projection component such as a head-up display (HUD), has high display performance for projected images and suppresses reflection of the surrounding scenery. [Brief description of the drawings]

[0008] [Figure 1] FIG. 2 is a schematic diagram showing an example of a cross section of the projection image display member of the present invention. [Diagram 2] FIG. 2 is a schematic diagram showing an example of a cross section of the projection image display member of the present invention. [Diagram 3] FIG. 2 is a schematic diagram showing an example of a cross section of the projection image display member of the present invention. [Figure 4] Graph showing the incidence angle dependency of reflectance of a conventional transparent resin film for incident P-wave and S-wave light with a wavelength of 550 nm. [Diagram 5] Graph showing the incidence angle dependency of reflectance for P-wave and S-wave incident light with a wavelength of 550 nm for a conventional light-reflecting multilayer laminate film. [Figure 6] 1 is a graph showing the incidence angle dependence of reflectance for incident P-wave and S-wave light with a wavelength of 550 nm for the multilayer laminate films described in Patent Documents 1 and 2. [Figure 7] 4 is a graph showing the incidence angle dependency of the reflectance of a multilayer laminate film contained in a projection image display member of the present invention for incident light of P waves and S waves with a wavelength of 550 nm. [Figure 8] 1 is a schematic diagram showing an example of a concavo-convex structure included in a projection image display member of the present invention; [Figure 9] FIG. 2 is a schematic diagram illustrating the layer thicknesses of Layer A and Layer B of the multilayer laminate film of the present invention. [Figure 10] FIG. 2 is a schematic diagram illustrating the azimuth angle of the multilayer laminate film of the present invention. [Figure 11] FIG. 1 is a schematic diagram illustrating a projection image display device according to an embodiment of the present invention. [Figure 12] FIG. 1 is a schematic diagram showing the reflection characteristics in oblique directions for a conventional projection image display member using glass or a transparent resin film, a projection image display member using the films disclosed in Patent Documents 1 and 2, and a projection image display member using the multilayer laminate film of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Hereinafter, the projection image display member of the present invention will be specifically described. The projection image display member of the present invention has a visible light transmittance of 50% or more and 100% or less when incident perpendicularly to the projection image display member surface, and when visible light is incident at angles of 20°, 40°, and 60° with respect to the normal of the projection image display member surface, and the reflectance (%) of the P wave is Rp20, Rp40, and Rp60 respectively, it satisfies the relationship Rp20 ≦ Rp40 < Rp60, and Rp60 is 10% or more. When the reflectance (%) of the S wave is Rs20 and Rs60 respectively when visible light is incident at angles of 20° and 60° with respect to the normal of the projection image display member surface, it is a projection image display member in which Rs60 - Rs20 is 25% or less.

[0010] The embodiments of the present invention will be described below. However, the present invention is not construed as being limited to the embodiments including the following examples, and various changes can naturally occur within the scope that can achieve the object of the invention and does not deviate from the gist of the invention. Also, for the purpose of simplifying the explanation, some explanations will be given by taking as an example a projection image display member including a multilayer laminated film having a configuration in which two different thermoplastic resin layers are alternately laminated, which is one of the preferred embodiments of the present invention. However, it should be understood in the same way even when including a multilayer laminated film using three or more thermoplastic resins.

[0011] A specific example of the aspect of the projection image display member of the present invention will be described. As an example of the aspect of the projection image display member of the present invention, a configuration (FIG. 1) including a multilayer laminated film 1 in which a plurality of different thermoplastic resin layers are alternately laminated 51 layers or more can be cited. The antireflection layer 2 is a layer that prevents reflection on the surface of the projection image display member and is preferably located on at least one surface of the multilayer laminated film 1. As shown in FIG. 1A, by having the antireflection layer 2 on at least one surface of the multilayer laminated film 1, the oblique reflection of the S wave on the surface of the projection image display member can be suppressed, and Rs60 - Rs20 can be reduced (the aspect of FIG. 1A is an aspect having the antireflection layer 2 on both surfaces). As a result, when the projection image display member of the present invention is used in a projection image display device such as a head-up display (HUD), the reflection of the surrounding scenery other than the video can be suppressed.

[0012] In addition, as shown in Fig. 1B, the projection image display member of the present invention is also preferably configured to have a functional layer 3 on at least one surface of the multilayer laminate film 1 (the embodiment of Fig. 1B is an embodiment in which the multilayer laminate film 1 has functional layers 3 on both surfaces). Examples of the functional layer 3 include a hard coat layer, an abrasion-resistant layer, an anti-scratch layer, an anti-reflection layer, a color correction layer, an ultraviolet absorbing layer, a light stabilizing layer, a heat ray absorbing layer, a printing layer, a gas barrier layer, and an adhesive layer. These layers may be of a single layer or multilayer configuration, and one layer may have multiple functions.

[0013] Other examples of the projection image display member of the present invention include a laminate in which a transparent support 4 and a multilayer laminate film 1 are laminated (FIGS. 2A to 2C), and a laminate in which a multilayer laminate film 1 is located between two transparent supports 4 (FIGS. 3A to 3C). Specific examples of the transparent support 4 include glass and transparent resin substrates, and the thickness thereof is preferably 1 mm or more to provide support. There is no particular upper limit to the thickness of the transparent support 4, but an excessively large thickness unnecessarily increases the weight of the projection image display member, so that the thickness is preferably 10 mm or less.

[0014] The glass of the transparent support 4 may be not only single-layer glass but also laminated glass or tempered glass used in automobile front, side, and rear windows, plate glass of glass building materials, double-layer glass, vacuum glass, etc. In addition, the transparent resin substrate of the transparent support 4 is preferably polyethylene terephthalate, polycarbonate, acrylic, polyvinyl chloride, polyethylene, polypropylene, polymethylpentene and copolymers thereof, acrylonitrile-butadiene-styrene copolymer, etc. These transparent resin substrates may be a single component or a mixture of multiple types.

[0015] As a lamination method of the transparent support 4 and the multilayer laminate film 1, in addition to a method of directly laminating them as shown in FIG. 2A and FIG. 3A, a method of forming an adhesive layer 5 using a pressure-sensitive adhesive or adhesive and laminating them as shown in FIG. 2B, C, FIG. 3B, C, etc. can also be used. Examples of components that can be used as pressure-sensitive adhesives or 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 esters, polyisobutylene, etc. In addition, these pressure-sensitive adhesives and adhesives may be used alone or in combination, and may also be added with adhesion regulators, plasticizers, heat stabilizers, antioxidants, ultraviolet absorbers, antistatic agents, lubricants, colorants, crosslinking agents, etc. as necessary.

[0016] The form of these adhesives before processing may be liquid, gel, block, powder, film, etc. Methods for solidifying the adhesive layer may include solvent evaporation, moisture curing, heat curing, hardener mixing, anaerobic curing, ultraviolet curing, thermal melting and cooling, pressure-sensitive, etc. Lamination methods may include lamination molding, injection molding, vacuum molding, pressure molding, combined vacuum and pressure molding, etc. Projection image display members can be produced by using heating, pressure, and the above-mentioned methods for solidifying the adhesive layer.

[0017] The projection image display member of the present invention must have a transmittance of 50% or more and 100% or less for visible light incident perpendicularly to the surface of the projection image display member (meaning an angle of 0° with respect to the tangent plane of the surface of the projection image display member). Here, "the transmittance of visible light perpendicularly incident to the surface of the projection image display member is 50% or more and 100% or less" specifically means that the average transmittance of light with a wavelength of 400 to 700 nm perpendicularly incident to the surface of the projection image display member is 50% or more and 100% or less. Since the transmittance of light in the visible light region with a wavelength of 400 to 700 nm is high in this way, the projection image display member has transparency like transparent glass or transparent resin film. Therefore, when the background is observed through the projection image display member in such an embodiment from a direction perpendicular to the surface of the projection image display member, good visibility of the background can be obtained. From the above viewpoint, the transmittance is preferably 70% or more, more preferably 80% or more, and even more preferably 90% or more. If the transmittance is 90% or more, the user can view the background without feeling the presence of the projection image display member. From the viewpoint of feasibility, the upper limit of the transmittance is preferably 99%.

[0018] The transmittance of light incident perpendicularly to the surface of the projection image display component can be measured by measuring the transmittance of light with wavelengths of 400 to 700 nm at an incident angle θ = 0° using a spectrophotometer in 1 nm increments and calculating the average value (detailed measurement conditions are described below).

[0019] For the projection image display member of the present invention, when the reflectivities (%) of the respective P-waves when incident at angles of 20°, 40°, and 60° with respect to the normal of the projection image display member are defined as Rp20, Rp40, and Rp60, the relationship Rp20 ≦ Rp40 < Rp60 must be satisfied, and Rp60 must be 10% or more. The "reflectivity of the P-wave when visible light is incident" as referred to here is the average reflectivity of the P-wave in the wavelength range of 400 to 700 nm. The reflectivity (%) of this P-wave can be measured by measuring the reflectivity of the P-wave in the wavelength range of 400 to 700 nm at incident angles θ = 20°, 40°, and 60° with a spectrophotometer at 1-nm intervals and calculating the average value thereof (detailed measurement conditions will be described later). In the case of a general transparent substrate such as transparent glass or a transparent resin film, as the incident angle is gradually increased from 20° with respect to the normal of the film surface, the reflectivity of the P-wave, which is one of the polarized lights, decreases, and the reflectivity becomes 0% at an angle called the Brewster angle. Therefore, it is difficult for a general transparent substrate to transmit in the front direction and reflect the P-wave in the oblique direction.

[0020] When the reflectivities of the respective P-waves when incident at angles of 20°, 40°, and 60° with respect to the normal of the projection image display member surface are defined as Rp20, Rp40, and Rp60, the mode that satisfies the relationship Rp20 ≦ Rp40 < Rp60 and Rp60 is 10% or more is a mode that does not have an angle corresponding to the Brewster angle. Therefore, by adopting such a mode, it becomes possible to reflect the P-wave incident from an oblique direction with respect to the projection image display member surface. Rp60 is preferably 30% or more, more preferably 50% or more. As Rp60 increases, the displayability of the projection image when a P-wave image is projected onto the projection image display member surface improves. Although the upper limit of Rp60 is not particularly limited, it is 99% from the viewpoint of feasibility.

[0021] The transmittance of visible light perpendicularly incident on the projection image display member of the present invention is 50% or more and 100% or less, and when incident at angles of 20°, 40°, and 60° with respect to the normal of the projection image display member, the reflectance (%) of each P-wave is Rp20, Rp40, and Rp60, respectively. As an example of a method satisfying the relationship Rp20 ≦ Rp40 < Rp60 and Rp60 being 10% or more, for example, a method in an embodiment including a multilayer laminated film having the above characteristics will be described in detail below.

[0022] The projection image display member of the present invention preferably includes a multilayer laminated film in which 51 or more different thermoplastic resin layers are alternately laminated. In the present invention, when there are a plurality of types of thermoplastic resin layers having different compositions in the multilayer laminated film, and the refractive indices of these thermoplastic resin layers differ by 0.01 or more in any one of two orthogonal directions arbitrarily selected in the plane of the film and the direction perpendicular to the plane, it can be regarded that "a plurality of different thermoplastic resin layers exist." Further, alternately laminated means that layers made of different thermoplastic resins are laminated in a regular arrangement in the thickness direction. The thickness direction is the direction perpendicular to the film plane. The presence or absence of the laminated structure and the thickness of each layer can be measured by analyzing an image taken with a transmission electron microscope (TEM), and the details will be described later.

[0023] Specific examples of such an embodiment include those in which the multilayer laminate film is made of a layer (layer A) made of a first thermoplastic resin and a layer (layer B) made of a second thermoplastic resin, and the layers are laminated in this order, such as A(BA)n and B(AB)n (n is a natural number representing the number of repeating units, the same applies below). In addition, in the case where the multilayer laminate film is made of a layer (layer A) made of a first thermoplastic resin, a layer (layer B) made of a second thermoplastic resin, and a layer (layer C) made of a third thermoplastic resin, the arrangement is not particularly limited, and examples include those laminated in the thickness direction with a certain regularity, such as C(BA)nC, C(ABC)n, and C(ACBC)n. In this way, by laminating a plurality of thermoplastic resin layers having different optical properties such as refractive index in a regular arrangement, it is possible to express interference reflection that reflects light in a desired wavelength band due to the relationship between the difference in refractive index of each layer and the layer thickness.

[0024] In addition, when the number of layers of the multilayer laminate film is 50 or less, high reflectance may not be obtained in the desired wavelength band. The above-mentioned interference reflection can achieve a higher reflectance for light in a wider wavelength band as the number of layers increases, and a multilayer laminate film that reflects light in the desired wavelength band can be obtained. From the above viewpoint, the number of layers of the multilayer laminate film is preferably 401 layers or more, more preferably 801 layers or more. In addition, although there is no upper limit to the number of layers, as the number of layers increases, the manufacturing cost increases due to the increase in the size of the manufacturing equipment, and the handling property deteriorates due to the increase in the film thickness, so in reality, the practical range is about 10001 layers, and preferably about 2001 layers.

[0025] The transmittance of visible light incident perpendicularly to the multilayer laminated film can be lowered by reducing the refractive index difference in the direction parallel to the film surface between the two thermoplastic resin layers. For example, if the number of layers of the multilayer laminated film is within the aforementioned range, if the refractive index difference in the direction parallel to the film surface is 0.06 or less, the transmittance can be made 50% or more; if it is 0.04 or less, the transmittance can be made 70% or more; if the refractive index difference is 0.02 or less, it becomes easy to make the transmittance 80% or more. Note that the "refractive index difference in the direction parallel to the film surface" refers to the absolute value of the difference in the in-plane refractive index between adjacent thermoplastic resin layers (when two types of layers are designated as layer A and layer B, it refers to the difference in the in-plane refractive index between layer A and layer B; when three types of layers are designated as layer A, layer B, and layer C, it refers to the difference in the in-plane refractive index between layer A and layer B, the difference in the in-plane refractive index between layer B and layer C, and the difference in the in-plane refractive index between layer C and layer A). Also, reducing the refractive index difference in the direction parallel to the film surface is preferable because it can reduce Rs60 - Rs20 described later.

[0026] In order to obtain a multilayer laminated film that satisfies the relationship Rp20 ≦ Rp40 < Rp60 and has Rp60 of 10% or more, a method of adjusting the refractive index difference in the direction perpendicular to the film surface between the two thermoplastic resin layers and the number of 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 made. For example, when the number of layers reaches 801 layers, if the refractive index difference in the direction perpendicular to the film surface is 0.08 or more, the reflectance can be made 30% or more; if the refractive index difference is 0.12 or more, it becomes easy to make the reflectance 50% or more. As a result, when the reflectances (%) of the respective P waves incident at angles of 20°, 40°, and 60° with respect to the normal of the projection image display member are Rp20, Rp40, and Rp60, the relationship Rp20 ≦ Rp40 < Rp60 can be satisfied and Rp60 can be made 10% 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. Note that hereinafter, the refractive index in the direction perpendicular to the film surface may be referred to as the in-plane normal refractive index.

[0027] Methods for adjusting the reflection wavelength of the multilayer laminate film to a wavelength range of 400 to 700 nm include adjusting the in-plane refractive index difference between two thermoplastic resin layers, the number of layers, layer thickness distribution, and film formation conditions (e.g., stretching ratio, stretching speed, stretching temperature, heat treatment temperature, and heat treatment time).

[0028] In the projection image display member of the present invention, the multilayer laminate film has a structure in which two types of thermoplastic resin layers are alternately laminated, and when a layer made of a first thermoplastic resin is layer A and a layer made of a second thermoplastic resin is layer B, it is preferable that layer A contains a crystalline thermoplastic resin and layer B contains an amorphous thermoplastic resin as a main component. More preferably, layer A contains a crystalline thermoplastic resin as a main component and layer B contains an amorphous thermoplastic resin as a main component. Even more preferably, layer A contains a crystalline thermoplastic resin and layer B contains an amorphous thermoplastic resin as a main component. Here, the main component refers to a component contained in an amount of 70% by mass or more and 100% by mass or less when the total components constituting the layer are taken as 100% by mass. In addition, since the reflectance is high and the number of layers to be laminated is small, it is preferable that the difference in the perpendicular refractive index between layer A and layer B is high. In terms of the layer thickness distribution, it is preferable that the optical thickness of adjacent layers A and B satisfies the following formula (A). It is preferable that the crystalline thermoplastic resin in layer A and the amorphous thermoplastic resin in layer B are both polyesters.

[0029]

number

[0030] where λ is the reflected wavelength, n A is the surface refractive index of layer A, d A is the thickness of layer A, n B is the surface normal refractive index of layer B, d B is the thickness of layer B.

[0031] The layer thickness distribution is preferably a constant layer thickness distribution from one side of the multilayer laminate film to the opposite side, a layer thickness distribution that increases or decreases from one side of the multilayer laminate film to the opposite side, a layer thickness distribution in which the layer thickness increases from one side of the multilayer laminate film to the center of the film and then decreases, a layer thickness distribution in which the layer thickness decreases from one side of the multilayer laminate film to the center of the film and then increases, or a combination of these distributions. The layer thickness distribution is preferably changed in a continuous manner such as linear, geometric, or difference progression, or in a manner in which about 10 to 50 layers have approximately the same layer thickness and the layer thickness changes in a stepwise manner.

[0032] A layer having a thickness of 1% or more of the thickness of the multilayer laminate film itself can be preferably provided on both surface layers of the multilayer laminate film as a protective layer, and the thickness of each protective layer is preferably 4% or more of the total thickness of the multilayer laminate film. A thicker protective layer leads to suppression of flow marks during film formation, improvement of the accuracy of the actual layer thickness of each layer relative to the design, suppression of deformation of the thin layer in the multilayer laminate film during the lamination process with other films or molded bodies and after the lamination process, and pressure resistance. The upper limit of the thickness of the protective layer is 20% from the viewpoint of ensuring the lamination component parts necessary for the expression of interference reflection while suppressing the increase in the thickness of the multilayer laminate film. The thickness of the multilayer laminate film constituting the projection image display member of the present invention is not particularly limited, but is preferably 20 μm to 300 μm, for example. When it is 20 μm or more, the stiffness of the multilayer laminate film is strong and handleability can be ensured. When it is 300 μm or less, the stiffness of the multilayer laminate film is not excessively strong, and formability is improved.

[0033] In addition, functional layers such as a primer layer, a hard coat layer, an abrasion-resistant layer, a scratch-resistant layer, an anti-reflection layer, a color correction layer, an ultraviolet absorbing layer, a light stabilizing layer, a heat absorbing layer, a printing layer, a gas barrier layer, and an adhesive layer may be formed on at least one surface of the multilayer laminate film. These layers may be single-layered or multi-layered, and one layer may have multiple functions. In addition, the multilayer laminate film may contain additives such as ultraviolet absorbers, light stabilizers (HALS), heat absorbing agents, crystal nucleating agents, and plasticizers. These components can also be used in combination within a range that does not impair the effects of the present invention.

[0034] Thermoplastic resins used in the multilayer laminate film constituting the projection image display member of the present invention include linear polyolefins such as polyethylene, polypropylene, poly(4-methylpentene-1), and polyacetal, alicyclic polyolefins which are ring-opening metathesis polymers of norbornenes, addition polymers, and addition copolymers with other olefins, biodegradable polymers such as polylactic acid and polybutyl succinate, polyamides such as nylon 6, nylon 11, nylon 12, and nylon 66, aramid, polymethyl methacrylate, polyvinyl chloride, polyvinylidene chloride, polyvinyl alcohol, polyvinyl butyral, ethylene-vinyl acetate copolymer, poly Reacetal, polyglycolic acid, polystyrene, styrene copolymerized polymethylmethacrylate, polycarbonate, polypropylene terephthalate, polyethylene terephthalate, polybutylene terephthalate, polyethylene-2,6-naphthalate and other polyesters, polyethersulfone, polyetheretherketone, modified polyphenylene ether, polyphenylene sulfide, polyetherimide, polyimide, polyarylate, tetrafluoroethylene resin, trifluoroethylene resin, trifluorochloroethylene resin, tetrafluoroethylene-hexafluoropropylene copolymer, polyvinylidene fluoride, and the like can be used. Among these, it is more preferable to use polyester in particular from the viewpoints of strength, heat resistance, transparency, and versatility. These may be copolymers or mixtures of two or more resins.

[0035] The polyester refers to a resin having a molecular structure in which a dicarboxylic acid unit and a diol unit are linked by an ester bond. As the polyester, a polyester obtained by polymerization of a monomer mainly composed of an aromatic dicarboxylic acid or an aliphatic dicarboxylic acid and a diol is preferable. Here, examples of the aromatic dicarboxylic acid 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'-diphenylsulfonedicarboxylic acid. Examples of the aliphatic dicarboxylic acid include adipic acid, suberic acid, sebacic acid, dimer acid, dodecanedioic acid, cyclohexanedicarboxylic acid, and ester derivatives thereof. Among them, terephthalic acid and 2,6-naphthalenedicarboxylic acid, which exhibit a high refractive index, are preferable. These acid components may be used alone or in combination of two or more, and may be partially copolymerized with oxyacids such as hydroxybenzoic acid.

[0036] Examples of the diol component 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 preferably used. These diol components may be used alone or in combination of two or more.

[0037] The thermoplastic resin that is the main component of each layer of the multilayer laminate film of the present invention is preferably selected from, for example, polyethylene terephthalate and polymers thereof, polyethylene naphthalate and copolymers thereof, polybutylene terephthalate and copolymers thereof, polybutylene naphthalate and copolymers thereof, polyhexamethylene terephthalate and copolymers thereof, and polyhexamethylene naphthalate and copolymers thereof, among the above-mentioned polyesters.

[0038] In addition, 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 can be added to the thermoplastic resin alone or in combination to the extent that the properties of the resin are not deteriorated.

[0039] In terms of reducing reflections when used in a projection image display device such as a head-up display, the projection image display member of the present invention is required to have Rs60-Rs20 of 25% or less, where Rs20 and Rs60 are the reflectances (%) of S waves when visible light is incident at angles of 20° and 60° to the normal line of the projection image display member surface. From the above viewpoint, Rs60-Rs20 is preferably 20% or less, more preferably 10% or less. The smaller Rs60-Rs20 is, the more the oblique reflection of S waves is suppressed, so that when the projection image display member of the present invention is used in a projection image display device such as a head-up display, the reflection of surrounding scenery other than the image can be suppressed. The lower limit of Rs60-Rs20 is not particularly limited, but is 1% from the viewpoint of feasibility.

[0040] P waves and S waves can be defined as follows. When electromagnetic waves (light) are incident on the front surface of an object from an oblique direction, P waves are electromagnetic waves whose electric field components are parallel to the incident surface (linearly polarized light that oscillates parallel to the incident surface), and S waves are electromagnetic waves whose electric field components are perpendicular to the incident surface (linearly polarized light that oscillates perpendicular to the incident surface). The reflection characteristics of these P waves and S waves will be explained with reference to the drawings. Graphs (examples) showing the angle dependence of reflectance when light of P waves and S waves with a wavelength of 550 nm is incident on each film from air are shown in FIG. 4 for a conventional transparent resin film (general transparent substrate), FIG. 5 for a conventional light-reflecting multilayer laminate film, FIG. 6 for the multilayer laminate film described in Patent Documents 1 and 2, and FIG. 7 for the multilayer laminate film included in the projection image display member of the present invention. Here, a wavelength of 550 nm is shown as an example, but even for other visible light wavelengths, each film has approximately the same relationship as shown in FIGS. 4 to 7. 4 to 7, reference numerals 6 and 7 denote the reflectance of P waves and the reflectance of S waves, respectively.

[0041] As shown in FIG. 4, a typical transparent substrate follows the Fresnel formula, and the reflectance of P waves decreases with increasing incident angle, and after reaching 0%, it shows a tendency to increase again. On the other hand, the reflectance of S waves increases with increasing incident angle. As shown in FIG. 5, a conventional light-reflecting multilayer laminate film has a low transmittance because both P waves and S waves have a constant reflectance at an incident angle of 0 degrees, and the reflectance of both P waves and S waves increases with increasing incident angle. As shown in FIG. 6, the multilayer laminate film described in Patent Documents 1 and 2 has a characteristic that the reflectance of both P waves and S waves is low (transmittance is high) at an incident angle of 0 degrees, and the reflectance of both P waves and S waves increases with increasing incident angle. On the other hand, as shown in FIG. 7, the multilayer laminate film included in the projection image display member of the present invention has a low reflectance of both P waves and S waves (transmittance is high) at an incident angle of 0 degrees, the reflectance of P waves increases with increasing incident angle, and the reflectance of S waves remains almost unchanged or decreases even if the incident angle increases up to about 60 degrees, and shows a tendency to increase from about 70 degrees. Thus, the multilayer laminate film included in the projection image display member of the present invention has the feature that the reflection characteristics of the S wave and P wave of the transparent substrate are reversed. Here, the multilayer laminate film of the present invention reduces the refractive index difference between the two thermoplastic resin layers in the direction parallel to the film surface and increases the refractive index difference between the two thermoplastic resin layers in the direction perpendicular to the film surface, so that in the reflection in the oblique direction, the reflection of the P wave occurs due to interference reflection inside the multilayer laminate film, and the reflection of the S wave occurs due to surface reflection of the multilayer laminate film. Therefore, as a method for reversing the reflection characteristics of the S wave and P wave of the transparent substrate, it can be mentioned to suppress the surface reflection of the projection image display member or the multilayer laminate film.

[0042] As a method for making the projection image display member of the present invention have the reflection characteristics as shown in FIG. 7, there is a method for suppressing the reflection of the surface of the projection image display member, particularly the reflection of S waves in an oblique direction on the surface of the projection image display member. A specific example of such a method is, for example, having at least one low refractive index layer with a refractive index of 1.5 or less on at least one surface of the projection image display member. In this method, the low refractive index layer functions as an anti-reflection layer. Another example is an example in which at least one surface of the projection image display member includes a concave-convex structure in which the average interval between convex portions and the average height of the convex portions are both in the range of 10 nm to 400 nm. The refractive index here is the average refractive index in the in-plane direction and the direction perpendicular to the plane (if an isotropic resin is used, the refractive index in either one of the directions can be used instead). By forming these low refractive index layers and concave-convex structures on both sides of the projection image display member, the reflection of S waves in an oblique direction on the surface of the projection image display member can be further suppressed. In this way, by having the above-mentioned anti-reflection mechanism on the surface of the projection image display member, Rs60-Rs20 can be made smaller, and when the projection image display member of the present invention is used in a projection image display device such as a head-up display, reflections of the surrounding scenery other than the image can be suppressed.

[0043] A low refractive index layer with a refractive index of 1.5 or less can be formed, for example, by coating a low refractive index material, vapor deposition of metal oxide, sputtering, etc. The lower limit of the refractive index is 1.2 from the viewpoint of feasibility. Materials for coating a low refractive index material include hollow acrylic, hollow silicon oxide, colloidal silicon oxide, hollow silica, LaF in a binder resin. 3 , MgF 2Examples of the fluorine-containing compound include a mixture of fine particles such as fluorine-containing methacrylate and fluorine-containing polyfunctional methacrylate, and the fluorine-containing compound may be used as a binder resin. From the viewpoint of suppressing haze, the average particle size of the primary particles of the fine particles is preferably 20 nm to 200 nm, and more preferably 20 nm to 100 nm. In addition, it is preferable to suppress the aggregation of the particles by performing a surface treatment on the fine particles, thereby suppressing haze. As a method of surface treatment, it is preferable to use a silane coupling agent that has high affinity with the binder resin. Metal oxides used for deposition and sputtering include LiF, MgF 2 , SiO 2 , Na 5 Al 3 F 14 , Na 3 AlF 6 The average particle size of the primary particles of the fine particles can be measured by a dynamic light scattering method.

[0044] In the projection image display member of the present invention, the product n×d of the refractive index n and layer thickness d of the low refractive index layer is preferably 150 nm or more and 250 nm or less, more preferably 170 nm or more and 220 nm or less. A typical anti-reflection layer using a low refractive index material is designed to reduce reflection at an incident angle of 0°, and the value of n×d at that time is around 120 nm. Therefore, as the incident angle increases, the anti-reflection effect in oblique directions decreases. On the other hand, in the multilayer laminate film of the present invention, by setting the value of n×d to 150 nm or more and 250 nm or less, it is possible to provide an anti-reflection effect in oblique directions even if the incident angle increases.

[0045] It is also preferable that the projection image display member of the present invention has a high refractive index layer with a refractive index of 1.7 or more between the surface and the low refractive index layer with a refractive index of 1.5 or less. This high refractive index layer can be formed by coating a high refractive index material, vapor deposition of a metal oxide, sputtering, or the like. The high refractive index material is Nb 2 O 5 , Sb 2 O 3 , ZrO 2 , TiO 2 , Y2 O 3 , SiO, ZnO, In 2 O 3 , Ta 2 O 5 , CEO 2 , SnO 2 , ITO, ATO, etc. Examples of the method for forming the high refractive index layer include a method of applying a coating liquid in which fine particles of these high refractive index materials are mixed in a binder resin and drying it, and a method of forming a high refractive index layer made of the high refractive index material by deposition or sputtering. When the high refractive index material is used as the fine particles, the average particle size of the primary particles is preferably 20 nm to 200 nm from the viewpoint of suppressing haze, and more preferably 20 nm to 100 nm. In addition, it is preferable to suppress the aggregation of particles by performing surface treatment on the fine particles, thereby suppressing haze. As a method for surface treatment, it is preferable to use a silane coupling agent that has high affinity with the binder resin. The average particle size of the primary particles of the fine particles can be measured by dynamic light scattering.

[0046] The product nH×dH of the refractive index nH and layer thickness dH of the high refractive index layer is preferably 150 nm or more and 250 nm or less, more preferably 170 nm or more and 220 nm or less. A typical anti-reflection layer using a high refractive index material is designed to prevent reflection at an incident angle of 0°, and the value of nH×dH is around 120 nm. Therefore, as the incident angle increases, the anti-reflection effect in oblique directions decreases. In addition, the value of nH×dH is preferably 300 nm or more and 500 nm or less, more preferably 340 nm or more and 440 nm or less.

[0047] A concave-convex structure in which the average interval between convex portions and the average height of the convex portions are both in the range of 10 nm to 400 nm is also called a moth-eye structure. By having a concave-convex structure in which the average interval between convex portions and the average height of the convex portions are equal to or less than the wavelength of visible light in the range of 400 nm to 700 nm, reflection on the surface of the projection image display member can be reduced. FIG. 8 shows an example of the concave-convex structure included in the projection image display member of the present invention. In FIG. 8, reference numeral 8 denotes a projection image display member including a concave-convex structure, reference numeral 9 denotes an enlarged cross-sectional view of the vicinity of the concave-convex structure, reference numeral 10 denotes an enlarged top view seen from the concave-convex structure side, and reference numeral 11 denotes a projection image display member without a concave-convex structure. The concave-convex structure 12 may be formed on the surface of a projection image display member without a concave-convex structure (reference numeral 13 shows a cross-sectional view of the vicinity of the surface), but a configuration in which the convex portions 14 are directly formed on the projection image display member 13 without the substrate 15 may also be adopted. The shape of the convex portion 14 is preferably one in which the diameter of the convex portion decreases from the base 19 of the convex portion toward the tip 20 of the convex portion. By decreasing the diameter of the convex portion from the base 19 of the convex portion toward the tip 20 of the convex portion, the refractive index changes continuously from the tip 20 of the convex portion toward the base 19 of the convex portion, thereby reducing reflection and making it possible to suppress surface reflection of the projection image display member.

[0048] In addition, such a shape has a large effect of suppressing the reflection of S waves in an oblique direction. In FIG. 8, the cross-sectional shape of the convex portion 14 is shown as a bell shape, but it may be a cone shape or a triangular pyramid shape as long as the diameter of the convex portion 14 decreases from the base 19 of the convex portion toward the tip 20 of the convex portion. In FIG. 8, the bases of the convex portions are spaced apart from each other at intervals 18, but they may be in contact with each other. As the packing pattern of the convex portions 14, reference numeral 10 in FIG. 8 shows a hexagonal lattice, but it may also be a tetragonal lattice or a random packing pattern. However, a packing pattern in which the intervals 16 between the convex portions are narrow is preferable from the viewpoint of reducing surface reflection. The average interval between the convex portions and the average (average height) of the heights 17 of the convex portions can be obtained from a roughness curve obtained by measuring the surface shape of the concave-convex structure with a scanning probe microscope. The average interval between the convex portions can be obtained from half the average value of the length of the profile curve elements in the reference length in accordance with JIS B 601 (2013). The average height of the convex portion can be calculated from the average value of the heights of the profile curve elements over the reference length in accordance with JIS B 601 (2013) (details of the measurement method are described later).

[0049] Resins are usually used as materials for the convex portions 14 and the substrate 15, and examples of such materials include photocurable resins that are cured by ultraviolet light, visible light, infrared light, etc., and thermosetting resins that are cured by heat. Examples of photocurable resins include acrylic resins, polyester resins, epoxy resins, urethane resins, and copolymer resins thereof. It is also preferable to add a photopolymerization initiator to the photocurable resin to promote photocuring, and examples of such photopolymerization initiators include acetophenone-based, acyloxime-based, benzophenone-based, benzoin ether-based, thioxanthone-based, sulfonium salt-based, and iodonium salt-based. Examples of the thermosetting resin include silicone resins, fluorine resins, epoxy resins, acrylic resins, polyester resins, phenol resins, polyarylate resins, polyacetal resins, urea resins, alkyd resins, polyolefin resins, styrene resins, polyamide resins, polyimide resins, polyamideimide resins, polyurethane resins, melamine resins, cellulose resins, styrene-isoprene resins, polyvinyl acetate resins, polyvinyl alcohol resins, polyvinyl butyral resins, polycarbonate resins, diallyl phthalate resins, and isocyanate resins.

[0050] Methods for forming the uneven structure include filling a mold for forming the uneven shape with the above-mentioned resin and pressing it against the surface of the multilayer laminate film to transfer the resin in the mold to the surface, or forming an uncured layer of the above-mentioned resin on the surface of the multilayer laminate film and pressing the mold against it, and then applying light or heat such as ultraviolet light, visible light, or infrared light depending on the characteristics of the resin used to harden the resin.

[0051] In the projection image display member of the present invention, the ratio Rp60 to Rs60, Rp60 / Rs60, is preferably greater than 1.0, more preferably greater than 2.0, and even more preferably greater than 3.0. When the projection image display member is used in a projection image display device such as a head-up display, the brightness of the image is increased by projecting the projection image with P waves, and the reflection of the surrounding scenery other than the image can be suppressed by low Rs60-Rs20, so that the contrast of the projection image can be increased. In other words, the larger Rp60 / Rs60 is, the higher the contrast (image displayability) can be. The larger the refractive index difference in the direction perpendicular to the film surface between the two thermoplastic resin layers of the multilayer laminate film contained in the projection image display member of the present invention is, and the more the number of layers is increased, the larger the Rp60 can be, and the smaller the Rs60 can be by providing an anti-reflection mechanism on the surface of the projection image display member.

[0052] In the projection image display member of the present invention, the saturation of the reflected light of the P wave when incident at an angle of 60° to the normal line of the projection image display member is preferably 20 or less, more preferably 5 or less. Hereinafter, the "saturation of the reflected light of the P wave when incident at an angle of 60° to the normal line of the projection image display member" may be referred to as the "saturation of the reflected light of the P wave". The saturation of the reflected light of the P wave being 20 or less means that uniform reflection is realized over the entire wavelength range of visible light, and by adopting such an embodiment, coloring of the reflected light can be suppressed. Therefore, when the projection image display member is used in a projection image display device such as a head-up display, the color of the projected image displayed when the projected image is projected with the P wave is reproduced as approximately the same color as the image irradiated from the display. The lower limit of the saturation of the reflected light of the P wave when incident at an angle of 60° is 0, and the saturation can be measured based on JISZ8781-4 (2013), the details of which will be described later.

[0053] An example of a method for making the saturation of reflected light of P waves 20 or less will be described with reference to Fig. 9. By uniformly arranging the thicknesses of layer A and layer B, which reflect light in the wavelength range of 400 nm to 700 nm, in the multilayer laminate film included in the projection image display member of the present invention according to formula (A) as shown in Fig. 9, the standard deviation of the reflectance in that wavelength band can be made 10% or less. Here, Fig. 9 shows an example of an ideal layer thickness distribution of layers A and B in a multilayer laminate film having 401 layers, where the surface normal refractive index (nA) of layer A is 1.5 and the surface normal refractive index (nB) of layer B is 1.6, from the layer position on the film surface to layer position 401 on the opposite film surface. In reality, errors will occur from the ideal layer thickness as shown in Figure 9 due to factors such as the design accuracy of the equipment and the operational stability of the film production equipment. However, if the error at each layer position from layer position 1 to layer position 401 averaged from layer 1 to layer 401 is within approximately ±10%, the saturation of the reflected light of the P wave when incident at an angle of 60° to the normal to the multilayer laminate film can be made to be 20 or less.

[0054] Here, as a method for suppressing thickness errors, a structure in which two types of thermoplastic resin layers are alternately laminated will be described as an example. A multilayer laminate structure can be obtained by melting two types of thermoplastic resins, alternately laminating them using a lamination device, and melt-extruding the molten laminate into a sheet using a T-shaped die or the like, and suppressing the disorder of the layers of this molten laminate leads to suppression of thickness errors. One method for this is to provide a thick layer on the outermost layer of the molten laminate. The thickness of the outermost layer is preferably 1% or more, more preferably 4% or more, of the total thickness of the molten laminate. The "thickness of the outermost layer" here means the thickness of one outermost layer, and does not mean the total thickness of the outermost layers on both sides. It is more preferable to thicken the thickness of both outermost layers, not just one outermost layer. If the thickness of the outermost layer becomes too thick and the proportion of the outermost layer in the entire film increases, the proportion of the thin film layer that contributes to the reflection of the multilayer laminate film decreases, so the upper limit of the thickness of the outermost layer is 20%.

[0055] The projection image display member of the present invention preferably has an azimuth angle variation of Rp60 of 10% or less. Here, the azimuth angle refers to each azimuth angle (0°, 45°, 90°, 135°, 180°) when the azimuth angle in the main orientation axis direction of the projection image display member 21 of the present invention (interpreted as 8 when it has a concave-convex structure) is 0° as shown in FIG. 10, and the main orientation axis direction refers to the direction with the highest degree of orientation within the plane of the projection image display member. The degree of orientation can be measured by a known molecular orientation meter, and as the molecular orientation meter, for example, the molecular orientation meter MOA-2001 manufactured by KS Systems Co., Ltd. (currently Oji Scientific Instruments Co., Ltd.) can be used. The azimuth angle variation is the difference between the maximum and minimum values ​​of Rp60(0°), Rp60(45°), Rp60(90°), Rp60(135°), and Rp60(180°) measured at the above azimuth angles (0°, 45°, 90°, 135°, and 180°). The lower limit of the azimuth angle variation of Rp60 is 0%.

[0056] 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 to 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° in the azimuth angle in the main orientation axis direction of the multilayer laminate film, and five angles are adopted in a clockwise direction from this: 0°, 45°, 90°, 135°, and 180°. By keeping the azimuth angle variation of Rp60 at 10% 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. In order to reduce the azimuth angle variation of Rp60, for example, the refractive index unevenness in the in-plane direction of the multilayer laminate film contained in the projection image display member of the present invention can be reduced, and in order to reduce the refractive index unevenness in the in-plane direction of the film, the film can be stretched so as to reduce the difference in the orientation state between the longitudinal direction and the width direction of the film when biaxially stretching the film. This effect is one of the characteristics of the projection image display member of the present invention, and is an effect that cannot be achieved by a polarized reflective film.

[0057] The multilayer laminate film included in the projection image display member of the present invention has a structure in which two types of thermoplastic resin layers are alternately laminated, and it is preferable that the layer (layer A) made of a first thermoplastic resin is mainly composed of crystalline polyester, and the layer (layer B) made of a second thermoplastic resin is mainly composed of amorphous polyester, and the difference in the in-plane refractive index between the layer A and the layer B is 0.04 or less. Here, the "first thermoplastic resin" refers to the entire resin components constituting the layer A, and the "second thermoplastic resin" refers to the entire resin components constituting the layer B. "Layer A is mainly composed of crystalline polyester" means that the first thermoplastic resin contains 70% by mass or more and 100% by mass or less of crystalline polyester. "Layer B is mainly composed of amorphous polyester" means that the second thermoplastic resin contains 70% by mass or more and 100% by mass or less of amorphous polyester, and in the present invention, the main component can be interpreted in the same way. It should be noted that which of the two alternately laminated thermoplastic resin layers is to be layer A is determined by comparing the in-plane refractive index. More specifically, the layer having a relatively small refractive index perpendicular to the surface is referred to as layer A, and the thermoplastic resin constituting this layer is referred to as a "first thermoplastic resin."

[0058] The in-plane refractive index here refers to the refractive index in the direction parallel to the film surface, more precisely, the average value of the refractive index in the direction of the main orientation axis and the refractive index in the direction perpendicular to the main orientation axis. The perpendicular refractive index refers to the refractive index in the direction perpendicular to the film surface. Note that the refractive index in each direction of a resin that does not become oriented even when stretched, such as an amorphous resin, may be the value in the resin state. The in-plane refractive index and perpendicular refractive index of the layer located on the outermost surface can be measured with an Abbe refractometer at 25°C using sodium D line (wavelength 589 nm) as a light source and methylene iodide as a mounting liquid (details of the measurement method will be described later).

[0059] Amorphous means that the heat of crystal fusion ΔHm is 5 J / g or less, and more preferably, does not show a peak corresponding to crystal fusion. The heat of crystal fusion ΔHm can be measured by the following procedure. First, in accordance with JIS-K-7122 (1987), the resin is heated from 25°C to 300°C at a heating rate of 20°C / min (1stRUN), and after holding in that state for 5 minutes, the resin is quenched by flowing liquid nitrogen gas around the aluminum pan in which the resin is sealed so that the temperature is 25°C or less, and then the temperature is raised again from room temperature to 300°C at a heating rate of 20°C / min. In the differential scanning calorimetry chart of the 2ndRUN thus obtained, the heat of crystal fusion ΔHm is obtained from the peak area of ​​the melting peak. When a crystalline thermoplastic resin is used as one of the thermoplastic resins and an amorphous thermoplastic resin is used as the other, even when it is made into a multi-layer laminate film, only one melting point is shown. Furthermore, the melting enthalpy of the multi-layer laminate film is preferably 20 J / g or more.

[0060] In order to reduce the difference in refractive index parallel to the plane of the multilayer laminate film and increase the difference in refractive index perpendicular to the plane of the film, it is important that one of the thermoplastic resins is strongly oriented in the direction parallel to the film plane (the refractive index is large in the direction parallel to the film plane and small in the direction perpendicular to the film plane) while the other thermoplastic resin maintains isotropy (the refractive index is the same in the directions parallel and perpendicular to the film plane).

[0061] The fact that there is only one melting point indicates that, among the thermoplastic resins constituting the multi-layer laminate film, only one type is oriented and crystallized, and the other thermoplastic resins are in an amorphous state without orientation. By selecting a thermoplastic resin so that the in-plane refractive index difference is small, it becomes easy to increase the refractive index difference perpendicular to the plane. In addition, a melting enthalpy of 20 J / g or more indicates that the orientation and crystallization of the resin with a melting point is advanced, and by adopting such a mode, it becomes easy to increase the refractive index difference in the direction perpendicular to the multi-layer laminate film plane.

[0062] More preferably, the in-plane refractive index of the outermost layer constituting the multilayer laminate film is 1.61 or more. By increasing the in-plane refractive index of the outermost layer of the multilayer laminate film, the refractive index difference in the direction perpendicular to the multilayer laminate film surface can be easily increased. From the above viewpoint, the in-plane refractive index of the outermost layer constituting the multilayer laminate film is more preferably 1.63 or more. Here, the adjustment of the refractive index difference will be explained using an example of a multilayer laminate film having a configuration in which two types of thermoplastic resin layers are alternately laminated. If the thermoplastic resin constituting the outermost layer is a first thermoplastic resin and the thermoplastic resin constituting the other layer is a second thermoplastic resin, the first thermoplastic resin has a high in-plane refractive index and a small in-plane normal refractive index, and the second thermoplastic resin has both an in-plane refractive index and a normal refractive index close to the in-plane refractive index of the first thermoplastic resin. At this time, by further increasing the in-plane refractive index of the first thermoplastic resin and using a second thermoplastic resin having an in-plane refractive index and a normal refractive index close to the in-plane refractive index of the first thermoplastic resin, the difference in the normal refractive index between the two can be increased, and the difference in the in-plane refractive index between the two can be kept small, so that the front direction can have high transmittance.

[0063] The multilayer laminate film contained in the projection image display member of the present invention preferably contains a polycyclic aromatic compound as a copolymerization component as an amorphous thermoplastic resin. By containing a polycyclic aromatic compound such as naphthalene or anthracene, it becomes easy to increase both the in-plane refractive index and the plane perpendicular refractive index. More preferably, it is a copolymer containing three or more types of dicarboxylic acids and diols. In the case of a thermoplastic resin consisting of one type of dicarboxylic acid and one type of diol, orientation and crystallization are promoted during stretching due to its high symmetry, and the amorphous state may not be maintained. However, by containing a copolymer containing three or more types of dicarboxylic acids and diols, it becomes easy to maintain the amorphous state without the orientation and crystallization progressing during stretching.

[0064] The multilayer laminate film contained in the projection image display member of the present invention preferably contains a structure derived from alkylene glycol having a number average molecular weight of 200 or more in any of the layers constituting the multilayer laminate film. As described above, it is necessary to contain a large amount of aromatics in order to increase the refractive index, but by further containing a structure derived from alkylene glycol, it becomes easy to efficiently lower the glass transition temperature while maintaining the refractive index. As a result, it becomes easy to achieve an embodiment in which the in-plane refractive index of the layer containing the structure is 1.61 or more and the glass transition temperature is 90°C or less. By having a glass transition temperature of 90°C or less, thickness unevenness after stretching can be suppressed, and the lower limit is preferably 70°C or more. The molecular weight of the alkylene glycol is 1 It can be calculated from the H-NMR spectrum, and details of the measurement conditions etc. will be described later.

[0065] Particularly preferably, the second thermoplastic resin is amorphous and contains a structure derived from an alkylene glycol having a number average molecular weight of 200 or more, and more preferably, the second thermoplastic resin is composed only of an amorphous thermoplastic resin containing a structure derived from an alkylene glycol having a number average molecular weight of 200 or more. By mixing a small amount of a thermoplastic resin containing a structure derived from an alkylene glycol having a number average molecular weight of 200 or more with another amorphous resin, it is possible to efficiently lower the glass transition temperature while maintaining the in-plane refractive index of the amorphous resin. Furthermore, by making the thermoplastic resin itself a copolymer containing a structure derived from an alkylene glycol, it is possible to suppress the precipitation of the thermoplastic resin containing a structure derived from an alkylene glycol on the surface of the multilayer laminate film even when processing is performed under high temperature conditions.

[0066] Examples of alkylene glycol include polyethylene glycol, polytrimethylene glycol, and polytetramethylene glycol. The molecular weight of the alkylene glycol is preferably 200 or more and 2000 or less. By having the molecular weight of the alkylene glycol be 200 or more, the volatility of the alkylene glycol is suppressed to be low, so that the alkylene glycol is sufficiently incorporated into the polymer when synthesizing the thermoplastic resin, and as a result, the effect of lowering the glass transition temperature is sufficiently obtained. In addition, by having the molecular weight of the alkylene glycol be 2000 or less, the decrease in reactivity during the production of the thermoplastic resin is suppressed, and the thermoplastic resin becomes more suitable for the production of a multilayer laminate film.

[0067] More preferably, the multilayer laminate film included in the projection image display member of the present invention has a second thermoplastic resin that contains a structure derived from two or more aromatic dicarboxylic acids and two or more alkyl diols, and contains a structure derived from an alkylene glycol having a number average molecular weight of 200 or more. The second thermoplastic resin is preferably amorphous, yet realizes high in-plane refractive index and in-plane perpendicular refractive index comparable to those of an oriented crystalline thermoplastic resin, and exhibits a glass transition temperature that allows co-stretching with the crystalline thermoplastic resin. It is difficult to satisfy all of these requirements with a single dicarboxylic acid or alkylene diol, but by containing two or more aromatic dicarboxylic acids and two or more alkyl diols, it is possible to achieve a high refractive index with the aromatic dicarboxylic acid, a low glass transition temperature with multiple alkyl diols, and a non-crystallization by containing four or more dicarboxylic acids and diols.

[0068] A projection image display device using the projection image display member of the present invention will be described below. The image display device of the present invention is a projection image display device equipped with the projection image display member of the present invention and a light source that irradiates light onto the display surface, and one embodiment thereof is shown in Fig. 11. The projection image display device of the present invention shown in the left diagram of Fig. 11 irradiates light 23, which is the source of an image, from a light source 22 onto a projection image display member 21, and projects an image onto the projection image display member 21. Furthermore, by passing light 24, which is information on the surrounding scenery, through the projection image display member 21, a user 25 of the projection image display device can visually superimpose the image and the surrounding scenery.

[0069] Examples of the light source 22 include a liquid crystal projector, a laser projector, a DLP (Digital Light Processing) projector, an LCOS (Liquid crystal on silicon) projector, a liquid crystal display, and an organic EL display. The light (information) emitted from the light source 22 may be directly projected onto the projection image display member 21, or may be projected onto the projection image display member after being reflected by a mirror, collected through a lens, diffused, or passed through a polarizing reflecting member. A cold mirror that reflects only visible light is preferable as this mirror. A normal mirror that reflects light ranging from visible light to infrared rays causes a temperature rise due to infrared rays when sunlight that has entered the inside of the projection image display device is reflected by the mirror and irradiated onto the light source, but a cold mirror does not reflect infrared rays, so it can suppress a temperature rise of the light source 22. The polarizing reflecting member reflects light in one direction relative to its surface (reflection axis direction) and transmits light in a direction perpendicular to that direction (transmission axis direction), so that light such as sunlight that enters from the outside and causes a temperature rise inside the projection image display device can be reduced by about half. On the other hand, by adjusting the polarization of the light from the light source so that it matches the transmission axis direction of the polarizing reflector, it is possible to suppress attenuation of the brightness of the light projected from the light source.

[0070] Examples of projection image display devices using the projection image display member of the present invention include glasses-type devices worn on the head, and transparent screen devices that are used indoors, outdoors, or in the windows of buildings to project information while allowing the background to shine through.

[0071] From the viewpoint of reducing the occurrence of double images, the projection image display device of the present invention preferably has a P wave intensity (P wave intensity / (P wave intensity+S wave intensity)) of 51% or more of the intensity of light incident on the display surface of the projection image display member. The intensity of P waves in the intensity of light incident on the display surface of the projection image display member may be simply referred to as "P wave intensity". Hereinafter, the problems of projection image display devices such as head-up displays include the occurrence of double images and the problem of reduced visibility when wearing polarized sunglasses. As shown in FIG. 12, a conventional projection image display member (FIG. 12A, reference numeral 27) made of glass or transparent resin film reflects S waves incident obliquely and transmits P waves. For this reason, S waves are used as light for the projection image incident on the display surface of the projection image display member. Double images are generated when light is reflected on the front and back surfaces of the image display member 21, and the light rays are misaligned, causing the displayed image to appear double. In addition, the reduction in visibility when wearing polarized sunglasses occurs because the projected image reflected on the projected image display component is derived from S-waves, and when the projected image is viewed through polarized sunglasses, which absorb S-waves, the light of the projected image is absorbed by the polarized sunglasses.

[0072] The projection image display member using the film disclosed in Patent Documents 1 and 2 (FIG. 12B, reference numeral 28) reflects the P waves incident obliquely, so that the P waves can be used as the light of the projected image incident on the display surface of the projection image display member. The P waves are reflected only inside the film, and are not reflected on the front and back surfaces, so the problem of double images is reduced. In addition, since the P waves pass through polarized sunglasses, the decrease in visibility of the projected image caused by polarized sunglasses is also reduced. However, when the projection image display member using the film disclosed in Patent Documents 1 and 2 is used, there is a problem that the surrounding scenery other than the image is reflected because the S waves are reflected on both the front and back surfaces. On the other hand, the projection image display member of the present invention (FIG. 12C) reflects the P waves incident obliquely and suppresses the reflection of the S waves in the oblique direction. Therefore, while enjoying the advantage of using P waves to display the projected image, the reflection of the surrounding scenery other than the image is also reduced by suppressing the reflection of the S waves from the oblique direction.

[0073] From the above viewpoints, the intensity of the P waves is preferably 51% or more, more preferably 90% or more, and from the viewpoint of polarization control accuracy, the upper limit is about 99%. In the projection image display device of the present invention, when the intensity of the P waves is 51% or more, the incidence angle 24 of the light that is the source of the image is preferably 30° or more, more preferably in the range of 50° to 70°. As shown in FIG. 4, the reflectance of the P waves decreases from an incidence angle of 30° or more, and decreases significantly in the range of 50° to 70° in particular. Therefore, by making the projected image of the P waves incident on the projection image display member at the above incidence angle, the effect of suppressing double images is increased.

[0074] The projection image display device of the present invention preferably includes a polarization conversion element that converts the direction of the polarized light passing through the light source by 10% or more, inside the light source or between the projection image display member and the light source. As described above, it is preferable that the projection image irradiated from the light source is a P wave, but depending on the design of the light source, it may be difficult to irradiate the P wave, and only S wave can be irradiated. Therefore, by including a polarization conversion element that converts the direction of polarized light by 10% or more, it is possible to increase the intensity of the P wave in the light intensity of the projection image irradiated from the light source. From the above viewpoint, it is more preferable to convert the direction of polarized light by 40% or more, and even more preferable to convert by 90% or more, with the upper limit being about 99% from the viewpoint of polarization control accuracy.

[0075] A retardation plate with a phase difference of 100 nm or more is preferable as the polarization conversion element. A retardation plate with a phase difference of 100 nm or more has the characteristic of changing the polarization state of light passing through it. Therefore, when the main alignment axis direction in the in-plane direction of the retardation plate is 0°, and the azimuth φ of the vibration direction of the polarized light of the projected image is in the range of 0°<φ<90° with respect to the main alignment axis direction 0°, the polarization characteristics of the polarized light change when the polarized light passes through the retardation plate. In other words, when an S wave passes through the retardation plate with the azimuth angle φS of its vibration being 0°<φS<90°, some or all of the component is converted into a P wave.

[0076] The conversion of S waves to P waves by passing through a retardation film is determined by the phase difference (Re) of the retardation film and the azimuth angle (φS) between the principal orientation axis direction in the in-plane direction of the retardation film and the vibration direction of the incident S wave.

[0077] The retardation of the retardation plate is preferably such that the retardation (Re(590)) at a wavelength of 590 nm is 100 nm or more. For a λ / 4 plate having the effect of converting S waves to P waves and S waves, Re(590) is more preferably in the range of 100 nm to 180 nm. For a λ / 2 plate having the effect of converting S waves to P waves, Re(590) is more preferably in the range of 240 nm to 320 nm (280±40 nm). In other words, the retardation of the polarization conversion element at a wavelength of 590 nm is preferably 240 nm or more and 320 nm or less, or 100 nm or more and 180 nm or less.

[0078] Next, an example of phase difference and polarization conversion of S waves will be described. When the vibration direction of the S wave passes through a 280 nm retardation plate with Re(590) at an azimuth angle φS=45° with respect to the main alignment axis direction of the retardation plate, the vibration direction of the S wave is converted by 90° and becomes a P wave. Also, when Re(590) passes through a 140 nm birefringent layer with the vibration direction of the S wave at an azimuth angle φS=45° with respect to the main alignment axis direction of the retardation plate, half of the S wave is converted to a P wave. This conversion efficiency is greatest at an azimuth angle φS = 45° and the effect decreases as the angle moves away from 45°, so the angle φS between the azimuth of the S-wave vibration direction and the azimuth of the alignment axis of the retardation plate is preferably in the range of 0°<φS<90°, 90°<φS<180°, more preferably in the range of 15°<φS<75°, 105°<φS<165°, and even more preferably in the range of 30°<φS<60°, 120°<φS<150°.

[0079] The retardation plate is preferably made mainly of a thermoplastic resin or liquid crystal, and the thermoplastic resin is preferably made mainly of any one of polyvinyl alcohol, polycarbonate, cycloolefin, and polymethyl methacrylate. The polyvinyl alcohol, polycarbonate, cycloolefin, and polymethyl methacrylate are preferably made to have birefringence by stretching them in at least one direction in the form of a film or sheet. The liquid crystal is preferably an ethylenically unsaturated group such as an acryloyl group, a methacryloyl group, and a styryl group, an epoxy group, and a cationic polymerizable group such as an oxetane group. The shape of the liquid crystal may be a rod or a disk. After dispersing the liquid crystal in a matrix, it is preferably applied to a substrate or a multilayer laminate film and aligned in one direction. The alignment method may be a rubbing method in which a roller is pressed against the substrate and then rotated, or a photoalignment method in which linearly polarized light such as ultraviolet light or visible light is irradiated.

[0080] The retardation plate is preferably uniaxially oriented. When the retardation plate is uniaxially oriented, the amount of change in retardation with respect to the incident angle and azimuth angle is small, which is preferable because the dependence of the polarization conversion of S-waves on the incident angle and azimuth angle is small. The thickness of the retardation plate is not particularly limited, but is preferably, for example, 1 μm to 200 μm. When the retardation plate is mainly composed of a thermoplastic resin, it is more preferably 5 μm to 100 μm, and when the retardation plate is mainly composed of a liquid crystal, it is more preferably 1 μm to 20 μm. It is also preferable to laminate the retardation plate with a transparent support having a retardation close to 0 nm in order to provide support.

[0081] The transportation of the present invention will be described below. The transportation of the present invention is equipped with the projection image display device of the present invention. Preferred examples of the transportation include automobiles, railroad cars, and airplanes. In particular, automobiles equipped with a projection image display device (e.g., a head-up display) using the projection image display member of the present invention on one or more of the windshield, side window, and rear window are preferred.

[0082] Hereinafter, the manufacturing method of the multilayer laminate film constituting the projection image display member of the present invention will be specifically described with an example. When the multilayer laminate film contained in the projection image display member of the present invention has the above-mentioned configuration, a laminate structure of 51 layers or more can be produced by the following method. First, the first thermoplastic resin and the second thermoplastic resin are supplied in a molten state from two extruders, namely, extruder A corresponding to layer A and extruder B corresponding to layer B, and the molten thermoplastic resin from each flow path is laminated into 51 layers or more by a multi-manifold type feed block and a square mixer, which are known lamination devices, or by only a comb type feed block. Next, the molten laminate is melt-extruded into a sheet shape using a T-shaped die or the like, and then cooled and solidified on a casting drum to obtain an unstretched multilayer laminate film. As a method for improving the lamination accuracy of layers A and B, the methods described in JP-A-2007-307893, JP-A-4691910, and JP-A-4816419 are preferred. In addition, if necessary, it is also preferred to dry the thermoplastic resin used in layer A and the thermoplastic resin used in layer B. In this case, it is preferable to select each thermoplastic resin so that the layer made of the first thermoplastic resin (Layer A) contains a crystalline polyester as a main component, the layer made of the second thermoplastic resin (Layer B) contains an amorphous polyester as a main component, and the difference in the in-plane refractive index between Layer A and Layer B is 0.04 or less.

[0083] Subsequently, the unstretched multi-layer laminate film is stretched and heat-treated. As the stretching method, a known sequential biaxial stretching method or a simultaneous biaxial stretching method is preferable. The stretching temperature is preferably in the range of the glass transition temperature of the unstretched laminate film or higher to the glass transition temperature + 80°C or lower. The stretching ratio is preferably in the range of 2.0 to 8.0 times in the longitudinal direction and the width direction, respectively, and more preferably in the range of 3.0 to 6.0 times, and it is preferable to reduce the difference in the stretching ratio between the longitudinal direction and the width direction. The stretching in the longitudinal direction is preferably performed by utilizing the difference in peripheral speed between the rolls of the longitudinal stretching machine. In addition, the subsequent stretching in the width direction is preferably performed by utilizing a known tenter method. That is, the uniaxially stretched multi-layer laminate film can be stretched in the width direction by conveying the film while holding both ends in the width direction with clips and widening the distance between the opposing clips in the width direction.

[0084] It is also preferable to perform simultaneous biaxial stretching with a tenter. The case of performing simultaneous biaxial stretching will be described. An unstretched laminated film cast on a cooling roll is introduced into a simultaneous biaxial tenter, and while both ends in the width direction are held by clips, it is conveyed and stretched simultaneously and / or stepwise in the longitudinal direction and the width direction. Stretching in the longitudinal direction is achieved by widening the distance between the clips on the same side, and stretching in the width direction is achieved by widening the distance between the rails on which the clips run to widen the distance between the opposing clips. The tenter clips for performing the stretching and heat treatment in the present invention are preferably driven by a linear motor system. Other types include a pantograph system and a screw system, but the linear motor system is superior in that the degree of freedom of each clip is high and therefore the stretching ratio can be freely changed.

[0085] It is also preferable to perform a heat treatment after the stretching. The heat treatment temperature is preferably in the range of from the stretching temperature to the melting point of the thermoplastic resin of Layer A minus 10°C, and it is also preferable to perform a cooling step after the heat treatment at a temperature in the range of the heat treatment temperature minus 30°C. In order to reduce the thermal shrinkage rate of the film, it is also preferable to shrink (relax) the film in the width direction and / or length direction during the heat treatment step or 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 film is wound up by a winder to produce the multilayer laminate film of the present invention.

[0086] An example of a method for producing a projection image display member of the present invention will be described. As an example of the configuration shown in FIG. 1B, a hard coat is applied as a functional layer 3 on both surfaces of a multilayer laminate film 1, and an anti-reflection layer 2 is further laminated on both surfaces of the hard coat. As a material for the hard coat layer, a hard coat coating liquid consisting of a polymerization initiator, a solvent, and a hard coat layer curing material such as an acrylic compound or a urethane compound is applied to one surface of the multilayer laminate film 1. A continuous or batch coating method can be used. Examples of a continuous coating method include a method of applying a coating liquid to a transport film using a die or a gravure roll, and a method of spreading a coating liquid dropped using a fountain with a metabar. Examples of a batch coating method include a method of spreading a coating liquid dropped using a dropper or the like with a metabar.

[0087] Subsequently, after the application of the hard coat coating liquid, the multilayer laminate film 1 is heated to volatilize the solvent. The heating temperature at this time is preferably from the boiling point of the solvent -10°C to the boiling point of the solvent +50°C, and particularly preferably from the boiling point of the solvent to the boiling point of the solvent +30°C. After the solvent volatilization, the curable material is cured by irradiation with ultraviolet light or heating to form a hard coat layer corresponding to the functional layer 3. This ultraviolet light irradiation is preferably performed under reduced pressure or in an oxygen-free atmosphere such as a nitrogen atmosphere, in order to increase the hardness of the hard coat layer. The ultraviolet light irradiation intensity is preferably 100 mJ / cm2 in terms of the integrated light amount. 2 ~1500mJ / cm 2 and the heating temperature is preferably 120°C to 200°C. After forming a hard coat layer on one surface of the multi-layer laminate film 1, a hard coat layer is formed on the opposite surface in the same manner. After forming the hard coat layer, an anti-reflection layer 2 is formed by coating the above-mentioned low refractive index material, vapor deposition of metal oxide, sputtering, or the like. Then, an anti-reflection layer 2 on the opposite side is formed in the same manner. By the above-mentioned method, a projection image display member having the configuration shown in FIG. 1B is produced.

[0088] As an example of the configuration shown in FIG. 2C, a hard coat layer (corresponding to functional layer 3) is formed on one side of multilayer laminate film 1, and anti-reflection layer 2 is formed on the surface of the hard coat layer, and an adhesive layer 5, transparent support 4, and anti-reflection layer 2 are laminated on the surface opposite to the hard coat layer of multilayer laminate film 1. A hard coat layer and anti-reflection layer 2 are formed on one surface of multilayer laminate film 1 by the method described above. Next, an adhesive coating liquid consisting of a crosslinking agent, a solvent, and an adhesive material such as an acrylic compound or a silicon compound is applied as an adhesive layer to the surface opposite to the surface on which the hard coat layer is formed. The above-mentioned continuous or batch type coating method can be used as the coating method.

[0089] The coating is then heated to volatilize the solvent. The heating temperature is preferably between the boiling point of the solvent minus 10°C and the boiling point of the solvent plus 50°C, and more preferably between the boiling point of the solvent or higher and the boiling point of the solvent plus 30°C. After the solvent has volatilized, an adhesive layer is formed by UV curing through UV irradiation or by heat curing, which hardens the curable material through heating. This UV irradiation is preferably performed under reduced pressure or in an oxygen-free atmosphere, such as a nitrogen atmosphere, in order to increase hardness. The UV irradiation intensity is 100 mJ / cm2 in terms of the integrated light amount. 2 ~1500mJ / cm 2 The heating conditions for thermal curing are preferably a temperature of 120°C to 200°C.

[0090] After forming the adhesive layer 5, the adhesive layer 5 of the multilayer laminate film 1 is bonded to the plate glass which corresponds to the transparent support 4. Examples of the bonding method include various molding methods such as lamination molding, injection molding, vacuum molding, pressure molding, and vacuum / pressure molding. Finally, the anti-reflection layer 2 is formed by the above-mentioned method on the plate glass surface opposite to the adhesive layer 5, thereby producing a projection image display member having the configuration shown in Fig. 2C.

[0091] As an example of the configuration shown in FIG. 3C, a transparent support 4 is laminated via adhesive layers 5 on both sides of a multilayer laminate film 1, and a hard coat layer (corresponding to functional layer 3) and an anti-reflection layer 2 are laminated on the surface opposite to the adhesive layer of the transparent support 4. A polyvinyl butyral sheet and a 3 mm thick glass plate (corresponding to transparent support 4) are laminated on both sides of the multilayer laminate film 1, and a vacuum is applied for 30 minutes at a temperature of 140° C. using a vacuum laminator, for example, and then pressed for 60 minutes to bond each member, thereby obtaining a laminate in which the adhesive layer 5 and the glass plate are located on both sides of the multilayer laminate film 1. A hard coat layer and an anti-reflection layer 2 are formed on both surfaces of this laminate by the method described above, thereby producing a projection image display member having the configuration shown in FIG. 3C. EXAMPLES

[0092] The projection image display member of the present invention will be described in more detail below using examples, but the projection image display member of the present invention is not limited to the following embodiments.

[0093] [Methods for measuring physical properties and evaluating effects] The methods for measuring the characteristics and evaluating the effects are as follows.

[0094] (1) Number of layers in a multi-layer laminate film, thickness of the surface layer, thickness of layers inside the film, thickness of low refractive index layer with refractive index of 1.5 or less The number of layers of the multilayer laminate film, the thickness of the surface layer, and the thickness of the low refractive index layer with a refractive index of 1.5 or less were confirmed by observing the sample cut out in a cross section parallel to the thickness direction (direction perpendicular to the film surface) using a microtome with a transmission electron microscope (TEM). The cross-sectional photograph was taken using a transmission electron microscope JEM1400Plus (manufactured by JEOL Ltd.) at an acceleration voltage of 100 kV. The thickness of the surface layer of the multilayer laminate film and the thickness of the low refractive index layer with a refractive index of 1.5 or less were measured using the image processing software Image-Pro Plus ver.10 of the obtained TEM image. The layer thickness inside the film was measured by image analysis using the image processing software Image-Pro Plus ver.10 of the obtained TEM image. The image analysis processing was performed in a vertical thick profile mode, and the relationship between the thickness direction position and the average brightness of the area sandwiched between two lines in the width direction was read as numerical data, and the spreadsheet software "Excel" (registered trademark) (Microsoft Office365) was used to perform numerical processing of the position (nm) and brightness data with a five-point moving average. Furthermore, the data of the 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 distance between adjacent values ​​as the layer thickness of one layer. This operation was performed for each image, and the layer thicknesses of all layers were calculated to determine the layer thickness inside the film.

[0095] (2) Transmittance of visible light perpendicularly incident on the projection image display component, multi-layer laminate film Using a Hitachi spectrophotometer (U-4100 Spectrophotometer) with the standard configuration (solid measurement system), the transmittance at wavelengths of 400 to 700 nm at an incident angle θ = 0° was measured in 1 nm increments, and the average transmittance was calculated. Measurement conditions: slit was 2 nm (visible) / automatic control (infrared), gain was set to 2, and scanning speed was 600 nm / min. When the projection image display member had a curved surface rather than a flat surface, an angle of 0° with respect to the tangent plane of the projection image display member surface was considered to be perpendicular.

[0096] (3) Reflectance of the projected image display material, multilayer laminate film (Rp20, Rp40, Rp60, Rs20, R60, Rp60 / Rs60), and saturation of reflected light of P waves incident at 60° A variable angle reflectance unit and a Glan-Taylor polarizer were attached to a Hitachi spectrophotometer (U-4100 Spectrophotomater), and the reflectance of P waves and S waves in the wavelength range of 400 to 700 nm at incident angles θ = 20 °, 40 °, and 60 ° was measured in 1 nm increments. From the obtained reflectances, Rp20, Rp40, and Rp60 were calculated as the average reflectance of P waves in the wavelength range of 400 nm to 700 nm at incident angles of 20 °, 40 °, and 60 °, and Rs20 and Rs60 were calculated as the average reflectance of S waves, and Rp60 / Rs60 was calculated from Rp60 and Rs60. The tilt directions of 20 °, 40 °, and 60 ° were set along the main orientation axis of the film. In addition, the saturation of the reflected light of the P wave incident at 60° is calculated based on JISZ8781-4(2013) in the CIE1976 color space L * a * b * Of which a * , b * The saturation C is calculated using the P-wave reflectance spectrum at θ=60°, the spectral distribution of the C light source, and the XYZ color matching function under the C light source, and the XYZ values. * a as value * and b * The square root of the sum of squares was used.

[0097] (4) Reflectance of projected image display member and multilayer laminated film (Rp60(0°), Rp60(45°), Rp60(90°), Rp60(135°), Rp60(180°), azimuth angle variation) A variable angle reflection unit and a Glan-Taylor polarizer were attached to a Hitachi spectrophotometer (U-4100 Spectrophotometer), and the reflectance of P waves in the wavelength range of 400 to 700 nm at an incident angle of θ = 60° was measured in 1 nm increments for each of the five azimuth angles of 0°, 45°, 90°, 135°, and 180° clockwise from the azimuth angle of 0° in the direction of the main orientation axis of the film surface. From the obtained reflectance, the average reflectance of P waves in the wavelength range of 400 nm to 700 nm at an incident angle of 60° in each azimuth angle direction was calculated as Rp60 (0°), Rp60 (45°), Rp60 (90°), Rp60 (135°), and Rp60 (180°). Furthermore, the difference between the maximum and minimum values ​​of the obtained Rp60(0°), Rp60(45°), Rp60(90°), Rp60(135°), and Rp60(180°) was defined as the azimuth angle variation.

[0098] (5) In-plane refractive index and perpendicular refractive index of the outermost layer of multi-layer laminate film Using sodium D line (wavelength 589 nm) as a light source and methylene iodide as a mounting liquid, the in-plane refractive index and the perpendicular refractive index in the direction of the main orientation axis and the direction perpendicular to the main orientation axis of the film were measured at 25°C with an Abbe refractometer. The perpendicular refractive index was taken as the average value of the value measured from the side in the direction of the main orientation axis and the value measured from the side in the direction perpendicular to the main orientation axis. The refractive index obtained here indicates the refractive index of layer A.

[0099] (6) Main orientation axis direction The degree of orientation was measured using a molecular orientation analyzer MOA-7015 manufactured by Oji Scientific Instruments, and the direction with the greatest degree of orientation was determined as the main orientation axis direction.

[0100] (7) Measurement of uneven structure The shape of the uneven structure on the surface of the projection image display member on which the uneven structure was formed was measured using a Bruker scanning probe microscope NanoScopeV DimensionIcon. The probe was a Si cantilever (spring constant approx. 40 N / m), the scanning mode was tapping mode, and the scanning range was 5 μm square (scanning line: 512). From the obtained roughness curve, the average interval between convex parts was calculated from half the average value of the length of the profile curve element in the reference length in accordance with JIS B 601 (2013), and the average height of the convex parts was calculated from the average value of the height of the profile curve element in the reference length in accordance with JIS B 601 (2013).

[0101] (8) Glass transition temperature and melting point of resin 5 mg of resin pellets were weighed on an electronic balance, sandwiched between aluminum pans, and measured using a Rigaku DSCvesta Smart Loader, in accordance with JIS-K-7122 (2012), by raising the temperature from 25°C to 300°C at a rate of 20°C / min. The glass transition temperature (Tg) and melting point (Tm) were determined from the obtained DSC data.

[0102] (9) Refractive index of thermoplastic resin The refractive index of the resin pellets was measured using an Abbe refractometer at 25° C. using sodium D line (wavelength 589 nm) as a light source and methylene iodide as a mounting liquid. The refractive index of the resin pellets was measured by vacuum drying the resin pellets at 70° C. for 48 hours, melting them at 280° C., pressing them with a press, and then quenching them to prepare a sheet with a thickness of 200 μm, and measuring the refractive index of the sheet.

[0103] (10) Refractive index of layer B of multi-layer laminate film Since Layer B is an internal layer of the multilayer laminate film, it was not a multilayer laminate film, but a film of Layer B resin alone produced under the same stretching and heat treatment conditions as the multilayer laminate film, and the refractive index was measured using a Prism Coupler SPA-400 manufactured by Cylon Technology Co., Ltd. The wavelength of the laser used for the measurement was 633 nm, and the in-plane refractive index was calculated by averaging the values ​​measured on both sides of the film in the main orientation axis direction and in the direction perpendicular to the main orientation axis direction, and the perpendicular-to-plane refractive index was calculated by averaging the values ​​measured on both sides of the film in the main orientation axis direction and in the direction perpendicular to the main orientation axis direction.

[0104] (11) Verification of the refractive index of layer B of a multi-layer laminate film An optical simulation of reflectance was performed using the layer thickness of the multilayer laminate film obtained in (1), the refractive index of layer A of the multilayer laminate film obtained in (5), and the refractive index of layer B obtained in (10), and the optical simulation result was compared with the reflectance measured in (3). If the difference between the two was within ±3%, the refractive index of layer B obtained in (10) was considered to be the refractive index of layer B of the multilayer laminate film. The optical simulation was performed using a VBA program with the characteristic matrix method of optical thin films (Mitsunobu Kohiyama (2006). Optical thin film filter design, Optronics Co., Ltd.).

[0105] (12) Molecular weight of alkylene glycol The film was dissolved in HFIP-d2 (hexafluoro-2-propanol dideuteride) 1 H-NMR was measured. In the spectrum obtained, the area of ​​the signal having a peak at a chemical shift of 3.8 ppm was defined as S1, and the area of ​​the signal having a peak at a chemical shift of 3.9 ppm was defined as S2. The molecular weight of the alkylene glycol was calculated as S1 / S2×44 (44: formula weight of the repeating unit of ethylene glycol).

[0106] (13)IV (intrinsic viscosity) The viscosity was calculated from the solution viscosity measured using an Ostwald viscometer at 25°C after dissolving the material in orthochlorophenol at 100°C for 20 minutes.

[0107] (14) Head-up display evaluation A Dream Maker display (SP-133CM) was used as the light source, and the projection image display component was placed at an angle of 30° to the light source (light emitted vertically from the light source has an incident angle of 60° with respect to the normal direction to the surface of the projection image display component). White P-wave or S-wave information was projected from the light source onto the projection image display component, and the displayability of the projected image, color displayability of the projected image, double image visibility of the projected image, visibility of the background, and reflection of external light were evaluated visually. (Evaluation criteria for display quality of projected images) ◎: The projected image is very bright. ○: The projected image is bright. ×: The projected image is dark. (Evaluation criteria for color display of projected images) ◎: The projected image appears white. ×: Colors other than white are visible in the projected image. (Evaluation criteria for double image visibility in projected images) ◎: The projected image is clear and does not appear double. ×1: The projected image appears double. ×2: The projected image does not appear double, but is very dark. (Evaluation criteria for background visibility) ◎◎: The background looks particularly clear. ◎: The background is clear ○: The background looks natural ×: The background appears dark (Evaluation criteria for external light reflection) ◎: There is little reflection of external light. ○: External light is reflected, but this does not affect use. ×: External light is strongly reflected.

[0108] [Thermoplastic resin used in the film] The films used in the Examples and Comparative Examples were produced using the following resins, all of which were thermoplastic resins, with Resin A, Resin B, and Resin G being crystalline resins, and Resin C, Resin D, Resin E, Resin F, Resin H, and Resin I being amorphous resins. Resin A: Polyethylene terephthalate copolymer with IV = 0.67 (polyethylene terephthalate copolymerized with 10 mol% isophthalic acid component relative to the total acid component), refractive index = 1.57, Tg = 75°C, Tm = 230°C, ΔHm = 32 J / g. Resin B: polyethylene terephthalate with IV=0.65, refractive index=1.58, Tg=78°C, Tm=254°C, ΔHm=41 J / g. Resin C: A polyester blend of a 90:10 (mass ratio) of a polyethylene naphthalate copolymer with IV=0.67 (polyethylene naphthalate copolymerized with 40 mol% of terephthalic acid relative to the total acid component) and an aromatic ester having terephthalic acid, butylene groups, and ethylhexyl groups and a number average molecular weight of 2000. Refractive index=1.62, Tg=90°C, Tm and ΔHm were not observed. Resin D: Polyethylene naphthalate copolymer with IV = 0.64 (polyethylene naphthalate copolymerized with 20 mol% isophthalic acid component based on the total acid component and 5 mol% polyethylene glycol having a molecular weight of 400 based on the total diol component), refractive index = 1.63, Tg = 85°C, Tm = 215°C, ΔHm = 2 J / g. Resin E: Polyethylene naphthalate copolymer with IV = 0.64 (polyethylene naphthalate copolymerized with 20 mol% isophthalic acid component based on the total acid component and 8 mol% polyethylene glycol having a molecular weight of 200 based on the total diol component). Refractive index = 1.63, Tg = 98°C, Tm and ΔHm were not observed. Resin F: polyethylene terephthalate copolymer with IV=0.73 (polyethylene terephthalate copolymerized with 33 mol% of cyclohexanedimethanol component relative to the entire diol component), refractive index=1.57, Tg=80° C., Tm and ΔHm were not observed. Resin G: polyethylene naphthalate with IV=0.64, refractive index=1.65, Tg=120° C., Tm=265° C., ΔHm=31 J / g. Resin H: Polyethylene terephthalate copolymer with IV=0.67 (polyethylene terephthalate copolymerized with 50 mol% of 2,6-naphthalenedicarboxylic acid component relative to the total acid component), refractive index=1.62, Tg=105°C, Tm and ΔHm were not observed. Note that Resin H is a resin in which the 2,6-naphthalenedicarboxylic acid component and the terephthalic acid component in the acid component are equal, but it is treated as a polyethylene terephthalate copolymer. Resin I: A polyester blended in a ratio of 90:10 (mass ratio) of a polyethylene terephthalate copolymer (polyethylene terephthalate copolymerized with 40 mol% of 2,6-naphthalenedicarboxylic acid component relative to the total acid component) with a number average molecular weight of 2000 and an aromatic ester having terephthalic acid, butylene group, and ethylhexyl group. Refractive index = 1.60, Tg = 88°C, Tm, ΔHm not observed.

[0109] (Material used for low refractive index layer: Material A) 20 g of hollow silica Sururia TR-113 (manufactured by Catalysts and Chemicals Industries Co., Ltd.: solid content concentration 20% by mass) was mixed with 4.4 g of methacryloxypropyltrimethoxysilane and 1.8 g of a 5% by mass aqueous solution of formic acid, and the mixture was stirred at 70° C. for 1 hour. 2 C=CH-COO-CH 2 -CF 2 -CF(CF 3 After adding 27.8 g of 2,2-azobisisobutyronitrile and 0.2 g of 2,2-azobisisobutyronitrile, the mixture was heated and stirred for 30 minutes at 70° C. Then, 333 g of isopropyl alcohol was added to dilute the mixture to obtain a material (material A, refractive index 1.38) used for the low refractive index layer with a solid content of 3.8% by mass.

[0110] (Material used for uneven structure: Material B) The ultraviolet-curing acrylic resin "Aronix" (registered trademark) UV3701 (manufactured by Toagosei Co., Ltd.) was used.

[0111] (Manufacturing of multi-layer laminated films) Multilayer laminate films and films were prepared as follows. The conditions are shown in Table 1, and the evaluation results when these were used as projection image display members are shown in Table 5 (Comparative Examples 1 to 15).

[0112] (Multi-layer laminate film 1) Resin A was used as the thermoplastic resin constituting layer A, and resin C was used as the thermoplastic resin constituting layer B. Resin A and resin C were each melted at 280°C in an extruder, passed through five FSS-type leaf disk filters, and then alternately merged in a 401-layer feed block (201 layers of layer A and 200 layers of layer B) designed so that the reflected wavelength of P waves at an incident angle of 70° is in the range of 400nm to 1000nm, while being metered with a gear pump so that the discharge ratio (lamination ratio) is resin A / resin C = 1.5. Next, the mixture was fed to a T-die and formed into a sheet, and then rapidly cooled and solidified on a casting drum kept at a surface temperature of 25°C while applying an electrostatic voltage of 8kV with a wire, to obtain an unstretched multilayer laminate film. The unstretched multi-layer laminate film was stretched longitudinally at a temperature of 95°C and a stretch ratio of 3.6 times, and both sides of the film were subjected to a corona discharge treatment in air. Then, an easy-adhesion layer-forming film coating liquid was applied to both sides of the film, which was a mixture of (polyester resin with a glass transition temperature of 18°C) and (polyester resin with a glass transition temperature of 82°C) at 50 parts by mass / 50 parts by mass, and further mixed with 3 parts by mass of silica particles with an average primary particle diameter of 100 nm relative to the mixed resin. Here, the average particle diameter of the primary particles can be measured by a dynamic light scattering method. Then, the obtained uniaxially stretched multi-layer laminate film was held at both ends in the width direction with clips and introduced into a tenter, and was stretched transversely at a temperature of 115°C and a stretch ratio of 3.8 times. Furthermore, the multi-layer laminate film after the transverse stretching was subjected to a heat treatment at 220°C and a 3% width direction relaxation, and cooled at 100°C, and a multi-layer laminate film with a thickness of 50 μm (thickness of both surface layers: 5.0 μm) was obtained. The film thickness, number of layers, surface layer thickness, and layer ratio were adjusted by adjusting the take-up speed of the casting drum, the slit width of the feed block, and the discharge amount, respectively.

[0113] (Multi-layer laminated film 2~5, 8~12, 14, 15) A multilayer laminate film was obtained in the same manner as in Example 1, except that the resin of each layer, the number of layers, the thickness of the surface layer, the total thickness, the lamination ratio, and the film-forming conditions were as shown in Table 1. The evaluation results of the obtained multilayer laminate film and the laminate are shown in Table 2. The layer configuration was an alternating lamination of layers A and B, and the outermost layers on both sides were layers A. The thickness of each layer was controlled by a feed block designed so that the reflected wavelength of P waves at an incident angle of 70° was in the range of 400 nm to 1000 nm.

[0114] As a result of verifying the refractive index of layer B of the multilayer laminate film in (11), the difference between the two was within ±3%. Therefore, the refractive index of layer B obtained in (10) was regarded as the refractive index of layer B of the multilayer laminate film.

[0115] (Multi-layer laminate film 6) Two multi-layer laminate films 4 were bonded together with an acrylic adhesive having a thickness of 10 μm to prepare a multi-layer laminate film.

[0116] (Multi-layer laminate film 7) Two multi-layer laminate films 5 were bonded together with an acrylic adhesive having a thickness of 10 μm to prepare a multi-layer laminate film.

[0117] (Film 13) Resin B was used as the thermoplastic resin. The resin was melted at 280°C in an extruder, passed through five FSS-type leaf disk filters, and then fed to a T-die and molded into a sheet. The film was then quenched and solidified on a casting drum maintained at a surface temperature of 25°C while applying an electrostatic voltage of 8 kV with a wire, to obtain an unstretched film. The unstretched film was stretched longitudinally at a temperature of 90°C and a stretch ratio of 3.3 times, and both sides of the film were subjected to a corona discharge treatment in air, and the easy-adhesion layer-forming film coating liquid used in Example 1 was applied to the treated surfaces of both sides of the film. Thereafter, the uniaxially stretched multi-layer laminate film was held at both ends in the width direction with clips and introduced into a tenter, and stretched transversely at a temperature of 100°C and a stretch ratio of 3.5 times, followed by heat treatment at 230°C and 3% width direction relaxation, and cooled at 100°C to obtain a film having a thickness of 50 μm.

[0118] (Examples 1 to 4, Comparative Examples 16 to 18) For the multilayer laminate films 3, 4, 6, 10, film 13, and multilayer laminate films 14 and 15, material A was applied to one surface with a bar coater (#4) and then dried at 100°C for 1 minute. Then, using a 160W / cm high pressure mercury lamp, the illuminance was 600W / cm. 2 , cumulative light intensity 800mJ / cm 2 The projection image display member was irradiated with ultraviolet light at an oxygen concentration of 0.1% by volume to produce a projection image display member having an anti-reflection layer of a low refractive index layer on one surface. The evaluation results and the results of the head-up display evaluation are shown in Table 2. In the head-up display evaluation, light was irradiated onto the surface on the low refractive index layer side.

[0119] (Examples 5 to 16) For each of the multi-layer laminate films 1 to 12, material A was applied to one surface with a bar coater (#6) and then dried at 100°C for 1 minute. Then, the multi-layer laminate films were irradiated with light of 600 W / cm using a 160 W / cm high-pressure mercury lamp. 2 , cumulative light intensity 800mJ / cm 2 The projection image display member was irradiated with ultraviolet light at an oxygen concentration of 0.1% by volume to produce a projection image display member having an anti-reflection layer of a low refractive index layer on one surface. The evaluation results and the results of the head-up display evaluation are shown in Table 3. In the head-up display evaluation, light was irradiated onto the surface on the low refractive index layer side.

[0120] (Examples 17 to 28) For the multilayer laminate films 1 to 12, projection image display members were produced in the same manner as in Examples 5 to 16, except that an antireflection layer was formed on one surface of each of the multilayer laminate films 1 to 12 in the same manner as in Examples 5 to 16, and then an antireflection layer was formed on the other surface in the same manner. The evaluation results and the head-up display evaluation results are shown in Table 3.

[0121] (Examples 29 to 32) For the multilayer laminate films 3, 4, 6, and 10, material B was applied to one surface to a thickness of 1 μm, and a moth-eye structure Ni electroforming die (HT-AR-09C) manufactured by INOX Co., Ltd. was used as a die for forming the uneven structure, and the die was pressed against the material B side. After that, a 160 W / cm high-pressure mercury lamp was used to illuminate the multilayer laminate film surface on the side opposite the die with an illumination intensity of 600 W / cm. 2 , cumulative light intensity 800mJ / cm 2 The projection image display member was irradiated with ultraviolet light at an oxygen concentration of 0.1 volume % to produce a projection image display member having an anti-reflection layer with a concave-convex structure on one surface. The evaluation results and the head-up display evaluation results are shown in Table 4. In the head-up display evaluation, light was irradiated onto the surface with the concave-convex structure.

[0122] (Examples 33 to 36) For the multilayer laminate films 3, 4, 6, and 10, a projection image display member was produced in the same manner as in Examples 29 to 32, except that an antireflection layer with a concave-convex structure was formed on one surface by the method shown in Examples 29 to 32, and then an antireflection layer with a concave-convex structure was similarly formed on the other surface. The evaluation results and the head-up display evaluation results are shown in Table 4.

[0123] (Comparative Examples 1 to 15) The multilayer laminate film or the film itself was evaluated as a projection image display member without providing an antireflection layer to the multilayer laminate film or the film 1 to 15 in order. The evaluation results and the head-up display evaluation results are shown in Table 5.

[0124] (Examples 37 to 48, Comparative Examples 19 to 23) A film (projection image display member) shown in Table 6 was attached to a 2 mm thick, A4 size glass plate with a 10 μm thick acrylic adhesive to prepare a projection image display member. The surface of the film to be attached to the glass plate was the surface without the anti-reflection layer. Using the prepared projection image display member, a head-up display evaluation was carried out with the polarization of the projected image incident on the projection image display member set as shown in Table 6. At this time, the projection image display member was placed so that the film surface was the viewing side. The evaluation results and the head-up display evaluation results are shown in Table 6.

[0125] (Examples 49 to 60) Material A was applied to the glass plate side surface of the projection image display members used in Examples 37 to 48 using a bar coater (#6). After that, the materials were dried at 100°C for 1 minute, and then irradiated with 600 W / cm illuminance using a 160 W / cm high pressure mercury lamp. 2 , cumulative light intensity 800mJ / cm 2 The projection image display member was irradiated with ultraviolet light at an oxygen concentration of 0.1% by volume to produce a projection image display member having an anti-reflection layer with a low refractive index also on the surface on the glass plate side. A head-up display evaluation was carried out using the projection image display member produced. At this time, the projection image display member was placed so that the film surface was the viewing side. The evaluation results and the head-up display evaluation results are shown in Table 6.

[0126] (Examples 61 to 64) A 2 mm thick, A4 size glass plate was attached to the surface of the film (projection image display member of Examples 29 to 32) shown in Table 7, without the anti-reflection layer, with a 10 μm thick acrylic adhesive to prepare a projection image display member. A head-up display evaluation was carried out using the obtained projection image display member. Note that the projection image display member was placed so that the film surface was the viewing side. The evaluation results and the head-up display evaluation results are shown in Table 7.

[0127] (Examples 65 to 68) Material B was applied to the glass plate side surface of the projection image display members used in Examples 61 to 64 in order to a thickness of 1 μm, and a moth-eye structure Ni electroformed mold (HT-AR-09C) manufactured by INOX Co., Ltd. was pressed onto the glass plate side surface to form a concave-convex structure. Then, using a 160 W / cm high pressure mercury lamp, illumination of 600 W / cm was applied from the multilayer laminate film surface side opposite the mold. 2 , cumulative light intensity 800mJ / cm 2 The projection image display member was irradiated with ultraviolet light at an oxygen concentration of 0.1% by volume to produce a projection image display member having an anti-reflection layer with a concave-convex structure on one surface. A head-up display evaluation was carried out using the projection image display member obtained. Note that the projection image display member was placed so that the film surface was the viewing side. The evaluation results and the head-up display evaluation results are shown in Table 7.

[0128] [Table 1]

[0129] Multilayer laminate films 6 and 7 were made by laminating two of the same multilayer laminate films, and the film-forming conditions were recorded for the multilayer laminate film before lamination (the number of layers in multilayer laminate films 6 and 7 does not include the adhesive layer that bonds the two multilayer laminate films together). Since layer B is composed of an amorphous resin, its orientation does not change even when it is made into a multilayer laminate film, and therefore the in-plane refractive index and perpendicular-to-plane refractive index of layer B are equal to the refractive index of the layer B resin.

[0130] [Table 2]

[0131] [Table 3]

[0132] [Table 4]

[0133] [Table 5]

[0134] [Table 6]

[0135] [Table 7] [Industrial Applicability]

[0136] The projection image display member of the present invention is a projection image display member that, when used as a projection member for a head-up display or the like, can obtain high display performance of the projected image while suppressing the reflection of surrounding scenery other than the image. A projection image display device using the multilayer laminate film of the present invention can be suitably used for head-up displays (HUDs) and head-mounted displays (HMDs) used in vehicles such as automobiles, aircraft, electronic signboards, game machines, etc. [Explanation of symbols]

[0137] 1: Multi-layer laminated film 2: Anti-reflection layer 3: Functional layer 4: Transparent support 5: Adhesive layer 6: P wave reflectivity 7: S-wave reflectivity 8: Projection image display member including uneven structure 9: Enlarged cross-sectional view of the uneven structure 10: Enlarged top view from the uneven structure side 11: Projection image display member without uneven structure 12: Uneven structure 13: Cross-sectional view of the surface of a projection image display member without a concave-convex structure 14: Convex 15: Base material 16: Spacing between protrusions 17: Height of the convex part 18: Spacing of base of convex parts 19: Base of protrusion 20: Tip of the protrusion 21: Projection image display member 22:Light source 23: Light that is the source of images 24: Light that conveys information about the surrounding scenery 25: Users of projected image display devices 26: Angle of incidence of light that creates the image 27: Conventional projection image display materials using glass or transparent resin film 28: Projection image display member using a film disclosed in Patent Documents 1 and 2

Claims

1. A projection image display member having a transmittance of 50% or more and 100% or less for visible light perpendicularly incident on the surface of the projection image display member, and satisfying the relationship Rp20≦Rp40<Rp60, where Rp20, Rp40 and Rp60 are the reflectances (%) of P waves when visible light is incident at angles of 20°, 40° and 60° relative to the normal to the surface of the projection image display member, respectively, and Rp60 is 10% or more, and Rs60 - Rs20 is 25% or less, where Rs20 and Rs60 are the reflectances (%) of S waves when visible light is incident at angles of 20° and 60° relative to the normal to the surface of the projection image display member, respectively.

2. 2. The projection image display member according to claim 1, comprising a multi-layer laminate film in which 51 or more layers of different thermoplastic resins are alternately laminated.

3. 3. The projection image display member according to claim 2, wherein the multilayer laminate film has a configuration in which two types of thermoplastic resin layers are alternately laminated, the layer (layer A) made of a first thermoplastic resin has a crystalline polyester as a main component, the layer (layer B) made of a second thermoplastic resin has an amorphous polyester as a main component, and the difference in in-plane refractive index between the layer A and the layer B is 0.04 or less.

4. 4. The projection image display member according to claim 3, wherein the second thermoplastic resin contains a structure derived from an alkylene glycol having a number average molecular weight of 200 or more.

5. 5. The projection image display member according to claim 2, wherein the multi-layer laminate film is located on at least one surface of a transparent support.

6. 5. The projection image display member according to claim 2, wherein the multi-layer laminate film is positioned between transparent members.

7. 5. The projection image display member according to claim 1, wherein a ratio Rp60 / Rs60 of Rp60 to Rs60 is greater than 1.

0.

8. 5. The projection image display member according to claim 2, wherein the chroma of reflected light of a P wave when incident at an angle of 60° with respect to the normal to said multi-layer laminate film is 20 or less.

9. 5. The projection image display member according to claim 1, wherein the azimuth angle variation of Rp60 is 10% or less.

10. 5. The projection image display member according to claim 1, further comprising at least one low refractive index layer having a refractive index of 1.5 or less on at least one surface of said projection image display member.

11. 11. The projection image display member according to claim 10, wherein a product n×d of a refractive index n and a layer thickness d of the low refractive index layer is 150 nm or more and 250 nm or less.

12. 5. The projection image display member according to claim 1, wherein at least one surface of the projection image display member includes a concave-convex structure in which the average interval between convex portions and the average height of the convex portions are both in the range of 10 nm to 400 nm.

13. 5. A projection image display device comprising: a projection image display member according to claim 1; and a light source for irradiating light onto the display surface of the projection image display member.

14. 14. The projection image display device according to claim 13, wherein the intensity of P waves (P wave intensity / (P wave intensity+S wave intensity)) accounts for 51% or more of the intensity of light incident on the display surface of the projection image display member.

15. 14. The projection image display device according to claim 13, further comprising a polarization conversion element disposed inside said light source or between said projection image display member and said light source, said polarization conversion element converting the direction of polarized light passing through said light by 10% or more.

16. 16. The projection image display device according to claim 15, wherein the phase difference of the polarization conversion element at a wavelength of 590 nm is 100 nm or more.

17. 17. The projection image display device according to claim 16, wherein the phase difference of the polarization conversion element at a wavelength of 590 nm is 240 nm or more and 320 nm or less, or 100 nm or more and 180 nm or less.

18. A means of transportation comprising the projection image display device according to claim 13.

Images