Multilayer laminated film and projected image display member

Abstract

The present invention addresses the problem of providing a multilayer laminated film that transmits visible light in the front direction, is transparent, and has a near-infrared reflection function and a function of reflecting P-wave visible light in an inclined direction, and the present invention is a multilayer laminated film in which three or more types of resin layers are regularly arranged, when the permittivity of each layer at an energy loss of 2.5 eV measured by EELS is defined as a permittivity Xi (i = 1, 2, 3,...), and the layer A, the layer B, and the layer C are defined in this order from the layer having a large permittivity Xi, all of the following conditions (1)-(3) are satisfied. (1) The film has a repeating unit structure in which repeating units are laminated, the repeating units being arranged in the order of A layer / B layer / C layer / B layer. And (2) the repeating units having a total layer thickness of 250-630 nm in the repeating units account for 80-100% of the total repeating units. And (3) the A layer is a crystalline thermoplastic resin layer, and the B layer and the C layer are amorphous thermoplastic resin layers.

Description

Technical Field

[0001] This invention relates to a multilayer laminated film that, while transmitting visible light in the front direction and being transparent, also possesses near-infrared reflection capabilities and the ability to reflect P-wave visible light in the tilted direction. It further relates to projection image display components using this multilayer laminated film, projection image display devices using this projection image display component, and vehicles and buildings such as automobiles using this projection image display device. Background Technology

[0002] In recent years, due to environmental protection and restrictions on carbon dioxide emissions, heat-blocking glass, which can suppress the inflow of heat from the outside, especially from sunlight, in summer, has attracted much attention. Heat-blocking glass can be used as window glass for vehicles such as automobiles and trams, as well as buildings. Examples of such heat-blocking glass include: materials that contain heat-absorbing materials in the interlayer of laminated glass, which block heat rays (near-infrared rays) through the heat-absorbing materials (e.g., Patent Document 1); materials that block heat rays by forming a metal film on the glass surface through sputtering or the like to reflect near-infrared rays (e.g., Patent Document 2); and materials that insert polymer multilayer films with alternating polymer layers of different refractive indices between the glass and the interlayer film to reflect near-infrared rays and thus block heat rays (e.g., Patent Document 3), etc.

[0003] Among these methods, those using heat-absorbing materials suffer from reduced heat-blocking efficiency because sunlight incident from the outside is converted into heat energy, and the resulting heat radiates into the interior. Furthermore, the heat-absorbing materials absorb near-infrared radiation, causing a partial increase in glass temperature, sometimes leading to glass breakage due to the temperature difference with the outside. Additionally, methods that form a metallic film on the glass surface through sputtering or similar means are prone to coloring because they reflect not only near-infrared radiation but also visible light, and they also block electromagnetic waves, sometimes preventing the use of communication equipment inside.

[0004] Compared to methods using heat-absorbing materials, polymer multilayer films that reflect near-infrared light allow for control over their layer thickness and selection of the reflected wavelength. This enables selective reflection of near-infrared light, improving heat-blocking performance while maintaining visible light transmittance. Furthermore, because they do not contain metals or other materials that block electromagnetic waves, they maintain excellent electromagnetic transmittance.

[0005] As other requirements, in recent years, projection image display devices, which project images onto projection image display components such as laminated glass and display the projected image superimposed on the background seen through the projection image display component, have been widely installed in vehicles such as automobiles. These projection image display devices project S-wave images from a light source onto the projection image display component. However, to prevent ghosting caused by reflections from the back surface of the projection image display component, there are proposals to have a wedge angle in the interlayer film inserted into the laminated glass (e.g., Patent Document 4). However, when wearing polarized sunglasses, there is a problem that the S-waves of visible light from the light source are absorbed by the polarized sunglasses, making it impossible to see the projected image. To address this problem, a method has been proposed to resolve ghosting by arranging a polarized light reflective film in the laminated glass and incident the P-wave image at the Brewster angle of the glass (Patent Document 5). In addition, as another method to solve this problem, a method has been proposed to resolve ghosting by arranging a multilayer laminated film in the laminated glass that transmits light in the front direction but only reflects P-waves in the tilt direction, so that the P-wave image is incident at the Brewster angle of the laminated glass (Patent Document 6).

[0006] Existing technical documents

[0007] Patent documents

[0008] Patent Document 1: Japanese Patent Application Publication No. 2010-17854

[0009] Patent Document 2: Japanese Patent Application Publication No. 2001-310407

[0010] Patent Document 3: International Publication No. 2005 / 040868

[0011] Patent Document 4: International Publication No. 2018 / 181687

[0012] Patent Document 5: International Publication No. 2005 / 017600

[0013] Patent Document 6: International Publication No. 2019 / 198635 Summary of the Invention

[0014] The problem that the invention aims to solve

[0015] However, regarding the reflective functions of the multilayer laminated film reflecting near-infrared light described in Patent Document 3 and the multilayer laminated film reflecting P-waves in the visible light region described in Patent Document 6, each uses different multilayer laminated films to achieve this function. That is, since near-infrared light and visible light are in different wavelength regions, multilayer laminated films with different optical designs are required. Therefore, if laminated glass or the like is to have both near-infrared and P-wave reflection functions, two different multilayer laminated films are needed. In this case, two different multilayer laminated films need to be manufactured separately, laminated together, and then applied to laminated glass, but the increased film thickness causes wrinkles and deformation in the laminated glass.

[0016] Furthermore, to improve the adhesion between laminated glass and the multilayer film and to make the multilayer film conform to the curved shape of the laminated glass, heating is usually performed when applying the multilayer film to the laminated glass. However, it is generally difficult to make the thermal shrinkage characteristics of two different multilayer films the same. When these multilayer films are laminated, the degree of wrinkling and deformation due to their different thermal shrinkage characteristics becomes stronger.

[0017] That is, the present invention aims to provide a multilayer film that is transparent while transmitting visible light in the front direction, and also has the functions of reflecting near-infrared light and reflecting P-wave visible light in the tilt direction.

[0018] Methods for solving problems

[0019] The present invention aims to solve the above-mentioned problems. The first multilayer film and the second multilayer film of the present invention have the following configuration.

[0020] The first multilayer laminated film of the present invention is a multilayer laminated film composed of three or more resin layers arranged in a regular manner. The dielectric constant of each layer is set as X, where X is the dielectric constant obtained by electron energy loss spectroscopy (EELS measurement) at a loss energy of 2.5 eV. i (i=1, 2, 3, ...), and from the above dielectric constant X i When the larger layers are sequentially designated as layer A, layer B, and layer C, all of the following conditions (1) to (3) must be met.

[0021] (1) A repeating unit structure formed by stacking repeating units, wherein the repeating units are arranged in the order of layer A / layer B / layer C / layer B.

[0022] (2) The number of units with a total layer thickness of 250 nm or more and 630 nm or less in each of the above repeating units is 80% or more and 100% or less relative to all repeating units.

[0023] (3) The multilayer laminated film is composed of a combination of layer A being a crystalline thermoplastic resin layer and layers B and C being amorphous thermoplastic resin layers.

[0024] The second multilayer film of the present invention has a dielectric constant X, which is obtained by electron energy loss spectroscopy (EELS measurement) at a loss energy of 2.5 eV. i When, the above dielectric constant X i A repeating unit structure in which three different resin layers (layer A, layer B, and layer C) are arranged in the order of layer A / layer B / layer C / layer B. Within the repeating unit, the number of units with a total layer thickness of 250 nm or more and 630 nm or less constitutes 80% or more and 100% of all repeating units. Within the repeating unit, the number of repeating units with a stack ratio (A / B) of the total thickness of layer A relative to layer B and a stack ratio (C / B) of the total thickness of layer C relative to layer B respectively within the range of 0.8 or more and 1.3 or less constitutes 80% or more and 100% of all repeating units. The dielectric constant X... i In this context, the dielectric constant of layer A is set as X. A Let the dielectric constant of the B layer be X. B And the dielectric constant of the C layer is set to X. C When X is satisfied A >X B >X C ,

[0025] When incident at an angle of 60° relative to the normal to the film surface, the average visible light reflectance of P-waves is above 10% and below 99%.

[0026] The effects of the invention

[0027] According to the present invention, a multilayer laminated film can be provided that is transparent while transmitting visible light in the front direction, and has near-infrared reflection function and the function of reflecting P-wave visible light in the tilt direction. Attached Figure Description

[0028] Figure 1 The diagram illustrates the transmission and reflection of a multilayer film. (a) is a conventional near-infrared reflective multilayer film. (b) is a P-wave reflective multilayer film. (d) is the multilayer film of the present invention.

[0029] Figure 2 This is a schematic diagram illustrating the application of the laminated film of the present invention to laminated glass.

[0030] Figure 3The diagram shows the characteristic of the average reflectivity of P-wave and S-wave light with wavelengths of 400 nm to 700 nm as a function of the incident angle. (a) is a conventional transparent resin film, (b) is a conventional multilayer film that reflects light, (c) is a conventional multilayer film that transmits visible light but reflects near-infrared light, and (d) is the multilayer film of the present invention.

[0031] Figure 4 A graph showing the change in refractive index of layers A, B, and C of Example 1 and Comparative Example 1 with respect to the angle of incidence.

[0032] Figure 5 A graph comparing the average visible light reflectance of the multilayer film of the present invention with respect to the incident angle of the P-wave with the prior art.

[0033] Figure 6 A schematic diagram illustrating the distribution of the layer thicknesses of layers A, B, and C in the multilayer laminated film of the present invention.

[0034] Figure 7 A schematic diagram illustrating the azimuth angle of the multilayer film of the present invention.

[0035] Figure 8 This is a schematic diagram showing an example of a cross-section of the projection image display component of the present invention.

[0036] Figure 9 This is a schematic diagram showing another example of a cross-section of the projection image display component of the present invention.

[0037] Figure 10 A schematic diagram illustrating the projection image display device of the present invention.

[0038] Figure 11 A schematic diagram illustrating the effect of installing the projection image display device of the present invention.

[0039] Figure 12 A schematic diagram illustrating the projection image display device of the present invention.

[0040] Figure 13 This is a schematic diagram illustrating the evaluation of the head-up display in the embodiment. Detailed Implementation

[0041] The multilayer laminated film of the present invention will now be described in detail. The multilayer laminated film of the present invention includes the first multilayer laminated film of the present invention and the second multilayer laminated film of the present invention, and are sometimes collectively referred to as "the multilayer laminated film of the present invention".

[0042] The first multilayer laminated film of the present invention is a multilayer laminated film composed of three or more resin layers arranged in a regular manner. Its characteristic is that the dielectric constant of each layer, obtained by electron energy loss spectroscopy (EELS measurement) at a loss energy of 2.5 eV, is set as dielectric constant X. i (i=1, 2, 3, ...), and when the layers with the largest dielectric constant X are successively designated as layers A, B, and C, all of the following conditions (1) to (3) are met.

[0043] (1) A repeating unit structure formed by stacking repeating units, wherein the repeating units are arranged in the order of layer A / layer B / layer C / layer B.

[0044] (2) The units with a total layer thickness of 250 nm or more and 630 nm or less in each of the above repeating units account for more than 80% and less than 100% of all repeating units.

[0045] (3) The multilayer laminated film is composed of a combination of crystalline / amorphous / amorphous thermoplastic resin layers, namely, layer A, layer B, and layer C. That is, it is composed of a combination of crystalline thermoplastic resin layer A, and amorphous thermoplastic resin layers B and C.

[0046] The second multilayer film of the present invention has a dielectric constant X, which is obtained by electron energy loss spectroscopy (EELS measurement) at a loss energy of 2.5 eV. i When, the above dielectric constant X i A repeating unit structure consisting of three different resin layers (layer A, layer B, and layer C) arranged in the order of layer A / layer B / layer C / layer B. Within the repeating unit, units with a total layer thickness of 250 nm or more and 630 nm or less constitute 80% to 100% of all repeating units. Within the repeating unit, repeating units with a stack ratio (A / B) of the total thickness of layer A relative to layer B and a stack ratio (C / B) of the total thickness of layer C relative to layer B respectively within the range of 0.8 or more and 1.3 or less constitute 80% to 100% of all repeating units. The dielectric constant X... i In the above, the dielectric constant X of layer A is... A The largest, followed by the dielectric constant X of the aforementioned B layer. B The dielectric constant X of the aforementioned C layer is once again given. C That is, the dielectric constant X mentioned above... i In this context, the dielectric constant of layer A is set as X. A Let the dielectric constant of the B layer be X. B And the dielectric constant of the C layer is set to X. C When X is satisfied A >XB >X C Furthermore, when incident at an angle of 60° relative to the normal to the film surface, the average visible light reflectance of P-waves is above 10% and below 99%.

[0047] The following describes embodiments of the present invention, but the present invention should not be construed as limited to the embodiments included below. Various modifications can be made within the scope of achieving the purpose of the invention and without departing from the spirit of the invention.

[0048] use Figure 1 The differences between conventional near-infrared reflective multilayer films and P-wave reflective multilayer films and the multilayer film of the present invention (hereinafter, the multilayer film of the present invention) that transmits visible light in the front direction and is transparent, while also having near-infrared reflective function and reflecting P-wave visible light in the tilt direction. Figure 1 (a) shows the conventional near-infrared reflective multilayer film 1 and Figure 1 (b) shows a conventional visible light P-wave reflective multilayer film 2, each consisting of two different thermoplastic resin layers stacked alternately. Symbols 5 to 8 respectively represent one of the two different thermoplastic resin layers in the conventional near-infrared reflective multilayer film 5, another of the two different thermoplastic resin layers in the conventional near-infrared reflective multilayer film 6, one of the two different thermoplastic resin layers in the conventional P-wave reflective multilayer film 7, and another of the two different thermoplastic resin layers in the conventional P-wave reflective multilayer film 8.

[0049] on the other hand, Figure 1 The multilayer laminated film 4 of the present invention shown in (d) has three resin layers A, B, and C with different dielectric constants X, and has a repeating unit structure arranged in the order of A / B / C / B. In other words, it has a repeating unit structure formed by stacking repeating units arranged in the order of A / B / C / B. Figure 1 In (d), the symbols 9, 10, and 11 respectively represent layer A (sometimes simply referred to as layer A) of the multilayer laminated film of the present invention, layer B (sometimes simply referred to as layer B) of the multilayer laminated film of the present invention, layer C (sometimes simply referred to as layer C) of the multilayer laminated film of the present invention, and layer C (sometimes simply referred to as layer C) of the multilayer laminated film of the present invention. The multilayer laminated film of the present invention is preferably... Figure 1 The structure is a stack of (A layer / B layer / C layer / B layer) n / A layer (n is an integer) where layer A is arranged on the two outermost surfaces. Since the same type of resin layers are arranged on both surfaces, the film transport (especially during heating) using rollers and clamps at the film ends is facilitated, and film curling is prevented when the film shrinks due to heating. From the above point of view, this is particularly preferred.

[0050] Conventional near-infrared reflective multilayer film 1 transmits visible light incident from the front, reflects near-infrared light, and transmits P-waves in the oblique direction. On the other hand, conventional P-wave reflective multilayer film 2 transmits visible light incident from the front, transmits near-infrared light, and reflects P-waves in the oblique direction.

[0051] Therefore, when using these multilayer laminated films to fabricate films that transmit visible light incident along the frontal direction, reflect near-infrared light, and reflect P-waves in the oblique direction, it is necessary to fabricate... Figure 1 As shown in (c), a laminated film 3 (hereinafter sometimes simply referred to as laminated film 3) is formed by laminating a near-infrared reflective multilayer film 1 and a P-wave reflective multilayer film 2 using a transparent adhesive 12, etc. Because laminated film 3 possesses the characteristics of both near-infrared reflective multilayer film 1 and P-wave reflective multilayer film 2, therefore... Figure 1 As shown in (c), it transmits visible light 13 incident from the front direction, reflects near-infrared light 14, and reflects P-waves 15 in the tilt direction.

[0052] However, since the laminate 3 is made by laminating two multilayer films, the following problems arise: the film thickness increases, and the two multilayer films have different thermal shrinkage characteristics. Because of these problems, when the laminate 3 is applied to laminated glass, it causes wrinkles and deformation. Typically, during the lamination process in manufacturing laminated glass using multilayer films, the laminate containing the glass and the multilayer films is heated to improve the adhesion between the glass and the multilayer films, or to make the multilayer films conform to the curved shape of the glass. Therefore, the different thermal shrinkage characteristics of the two multilayer films constituting the laminate 3 exacerbate the degree of wrinkling and deformation.

[0053] On the other hand, such as Figure 1 As shown in (d), the multilayer laminated film 4 of the present invention, through a single multilayer laminated film, has the functions of transmitting visible light 13 incident from the front direction, reflecting near-infrared light 14, and reflecting P-waves 15 in the tilted direction. Therefore, excessive film thickness can be suppressed. Furthermore, since there are no multiple multilayer laminated films with different thermal shrinkage characteristics, when the multilayer laminated film of the present invention is applied to laminated glass, compared with the case where the laminated film 3 is used, the generation of wrinkles and deformation can be suppressed, and laminated glass with excellent appearance can be produced. It should be noted that when the laminated film 3 or the multilayer laminated film 4 of the present invention is applied to laminated glass, the laminated film 3 or the multilayer laminated film 4 of the present invention can be inserted inside the laminated glass. Figure 2 (a)) Laminating a laminated film 3 or the multilayer laminated film 4 of the present invention onto the surface of the laminated glass. Figure 2 (b)

[0054] Figure 2This document shows only an example of the multilayer laminated film 4 of the present invention, and an example of an embodiment of laminated glass (composition having a multilayer laminated film between glass panes) 16 and laminated glass (composition having a multilayer laminated film on the surface) 17. It should be noted that... Figure 2 In the middle, the multilayer laminated film 4 is bonded to the transparent support (glass) 18 through the adhesive layer 19.

[0055] The mechanism by which the multilayer film of the present invention transmits visible light in the front direction and is transparent, while also having near-infrared reflection function and reflecting P-wave visible light in the tilt direction, will be explained below.

[0056] The multilayer film of the present invention needs to have a dielectric constant X, which is obtained by electron energy loss spectroscopy (EELS) at a loss energy of 2.5 eV. i When, the above dielectric constant X i (i represents a layer. For example, X) A This is the dielectric constant of layer A. It is sometimes abbreviated as dielectric constant X or dielectric constant Xa. i A repeating unit structure consisting of three different resin layers (layer A, layer B, and layer C) arranged in the order of layer A / layer B / layer C / layer B, wherein the total layer thickness of the repeating units is 250 nm or more and 630 nm or less, accounting for 80% to 100% of all repeating units. Here, the repeating unit structure consisting of three resin layers (layer A, layer B, and layer C) arranged in the order of layer A / layer B / layer C / layer B refers to... Figure 1 As shown in (d), the structure is formed by repeatedly stacking layers A, B, C, and B in this order in a multilayer film. Furthermore, the so-called "dielectric constant X" i "Different" refers to a difference of more than 2% in dielectric constant. i "Three different resin layers" refers to three resin layers whose dielectric constant X is different regardless of their combination for comparison. The dielectric constant X of the three resin layers... i The dielectric constant X differs, resulting in reflection at the interfaces between layers. The reflected wavelength can be represented by the following equation (A). It should be noted that the dielectric constant X can be determined using EELS measurements, the details of which will be described later.

[0057]

[0058] Here, λ is the reflected wavelength, and n A Let d be the in-plane refractive index of layer A. A Let n be the thickness of layer A. B Let d be the in-plane refractive index of layer B. B n is the thickness of layer B. C Let d be the in-plane refractive index of layer C.C Let C be the thickness. The in-plane refractive index and thickness are values ​​in a repeating unit structure formed by arranging adjacent A / B / C / B layers. The in-plane refractive index here is the average of the refractive index along the principal orientation axis and the refractive index in a direction orthogonal to the principal orientation axis within the film surface. The definition and specific method of the principal orientation axis will be described later.

[0059] In addition, as a method for forming a stacked structure having repeating unit structures arranged in the order of layer A / layer B / layer C / layer B, wherein the total layer thickness of the repeating unit is 250 nm or more and 630 nm or less, the number of units is 80% or more relative to all repeating units, for example, a method of stacking extruded molten resin with a desired layer structure by means of a feed block, and adjusting the slit width of the feed block and the discharge amount of each molten resin.

[0060] Based on formula (A), if the total layer thickness within the repeating unit is 250 nm or more, it can reflect near-infrared light with a wavelength of 850 nm or more. On the other hand, if the total layer thickness within the repeating unit exceeds 630 nm, reflection occurs in the visible light region due to the effects of higher-order reflections, as described later. Consequently, the transparency of the multilayer film of the present invention decreases and it becomes discolored, which is therefore undesirable. Furthermore, when the total layer thickness within the repeating unit is less than 250 nm, the reflected wavelength is less than 850 nm. Moreover, if the total layer thickness is 200 nm or less, the reflected wavelength enters the visible light region. Therefore, the transparency of the multilayer film of the present invention decreases and it becomes discolored, which is also undesirable.

[0061] Therefore, from the viewpoint of combining transparency and heat insulation, the multilayer laminated film of the present invention requires that units with a total layer thickness of 250 nm or more and 630 nm or less within the repeating units account for 80% or more of all repeating units. By ensuring that units with a total layer thickness of 250 nm or more and 630 nm or less within the repeating units account for 80% or more of all repeating units, it is possible to suppress visible light reflection while reflecting near-infrared light with wavelengths from 850 nm to 2000 nm. Therefore, when the multilayer laminated film of the present invention is used in window components of automobiles and buildings, it is possible to ensure external visibility while reflecting near-infrared energy from the sun that penetrates into the vehicle or interior, thereby suppressing temperature rise inside the vehicle or interior. From the above viewpoint, the proportion of units with a total layer thickness of 250 nm or more and 630 nm or less within the repeating units is preferably 90% or more, more preferably 95% or more. It should be noted that the theoretical upper limit of this proportion is 100%.

[0062] As a method for adjusting the near-infrared reflectance of the multilayer film of the present invention, one example is adjusting the in-plane refractive index difference and the number of repeating units of layers A, B, and C. More specifically, the greater the in-plane refractive index difference (the difference between the largest and smallest) of layers A, B, and C, and the more repeating units there are, the higher the near-infrared reflectance.

[0063] It should be noted that even if the same resin is used in each layer and the number of repeating units is the same, the structure with constant layer thickness has a higher reflectivity in a specific wavelength band compared to the structure with distributed layer thickness. On the other hand, the structure with distributed layer thickness has a wider range of reflection bands. Therefore, the specific reflectivity cannot be determined solely by the in-plane refractive index difference and the number of repeating units. However, from the viewpoint that a certain level of reflectivity can be ensured through adjustments to thickness distribution and other factors within a wide range of multilayer film designs, the in-plane refractive index difference between layer A and layer B, and the in-plane refractive index difference between layer B and layer C, are preferably both 0.03 or more, more preferably both 0.07 or more, and even more preferably both 0.10 or more. From the same viewpoint, the in-plane refractive index difference between layer A and layer C is preferably 0.06 or more, more preferably 0.14 or more, and even more preferably 0.20 or more.

[0064] Generally, the higher the number of repeating units in a multilayer film, the higher the reflectivity can be for light across a wider wavelength range. Therefore, by increasing the number of repeating units, a multilayer film reflecting light in the desired wavelength range can be obtained. From this perspective, the number of repeating units is preferably 15 or more, more preferably 45 or more, further preferably 90 or more, and particularly preferably 140 or more. Furthermore, there is no upper limit to the number of repeating units, but as the number of repeating units increases, manufacturing costs increase due to the larger size of the manufacturing apparatus, and operability deteriorates due to the increased thickness of the multilayer film. Therefore, approximately 2500 is a practical range in reality, preferably 500, and further preferably 200. It should be noted that, from the viewpoint of improving near-infrared reflectivity, a number of units with a total layer thickness of 250 nm or more and 630 nm or less within the repeating units of the multilayer film of the present invention is more preferably within the above-mentioned preferred range.

[0065] The layer thickness distribution of the multilayer laminated film of the present invention is preferably as follows: a constant layer thickness distribution from one side of the multilayer laminated film to the opposite side; a layer thickness distribution that increases or decreases from one side of the multilayer laminated film to the opposite side; a layer thickness distribution that increases and then decreases from one side of the multilayer laminated film to the center of the film; a layer thickness distribution that decreases and then increases from one side of the multilayer laminated film to the center of the film; or a layer thickness distribution formed by combining these distributions; and so on. As for the variation of the layer thickness distribution, the following are preferred: a continuous variation such as linear, geometric, or difference series; a layer thickness that is substantially the same from about 12 to about 52 layers; or a layer thickness that has repeating units with substantially the same thickness for each layer, and the layer thickness and the thickness of the repeating units vary in a stepwise manner.

[0066] It is preferable to provide protective layers with a thickness of 1% or more of the overall thickness of the multilayer laminated film on both surfaces of the multilayer laminated film, and the thickness of each protective layer is preferably 4% or more relative to the overall thickness of the multilayer laminated film. A protective layer is sometimes located on the outermost layer of both sides of the multilayer laminated film, and it is provided from the viewpoint of protecting the multilayer laminated film. Increasing the thickness of the protective layer helps to suppress flow marks during film fabrication, improve the accuracy of the actual thickness of each layer relative to the design, suppress deformation of the thin film layer in the multilayer laminated film after lamination with other films and molded bodies, and improve extrusion resistance. It should be noted that, from the viewpoint of ensuring the necessary laminated components for interference reflection performance while suppressing the increase in the thickness of the multilayer laminated film, the upper limit of the thickness of the protective layer is less than 20% of the overall film thickness. The protective layer may be a single layer within a repeating unit or a single layer outside a repeating unit. When considered as a protective layer, the stacking ratios in the calculation of the total thickness of layer A relative to layer B (A / B) and the total thickness of layer C relative to layer B (C / B) of each repeating unit are not included. Furthermore, repeating units containing layers considered as protective layers are not included when counting all repeating units.

[0067] The thickness of the multilayer film of the present invention is not particularly limited, but is preferably, for example, 20 μm to 300 μm. If it is 20 μm or more, the stiffness of the multilayer film is enhanced, thus ensuring good operability. Furthermore, if it is 300 μm or less, the stiffness of the multilayer film is not excessively enhanced, and the formability is improved. In other words, by making the thickness within the above range, operability and formability are improved, and therefore, when used in projection image display components, it becomes easier to follow curved surfaces such as glass.

[0068] Furthermore, functional layers such as a base coating, hard coating, abrasion-resistant layer, scratch-resistant layer, anti-reflective layer, color-correcting layer, ultraviolet absorption layer, light-stabilizing layer, thermal absorption layer, printing layer, gas barrier layer, and adhesive layer can be formed on at least one surface of the multilayer laminated film. These layers can be single-layered or multi-layered, and a single layer can have multiple functions. Additionally, the multilayer laminated film may contain additives such as ultraviolet absorbers, light stabilizers (HALS), thermal absorbers, nucleating agents, and plasticizers. It should be noted that these components can also be used in combination without impairing the effects of the present invention.

[0069] The second multilayer film of the present invention requires that the number of repeating units in which the total thickness ratio (A / B) of layer A relative to layer B and the total thickness ratio (C / B) of layer C relative to layer B are both 0.8 or more and 1.3 or less, respectively, accounts for 80% or more and 100% or less of all repeating units. The dielectric constant X decreases in the order of layer A, layer B, and layer C. Here, "dielectric constant X decreases in the order of layer A, layer B, and layer C" means that the dielectric constant of layer A is set as X. A Let the dielectric constant of layer B be X. B And the dielectric constant of layer C is set to X. C When X is satisfied A >X B >X C A / B and C / B can be calculated by observing the cross-section parallel to the thickness direction of the multilayer film using a transmission electron microscope (TEM) and measuring the length of each layer (details of cross-sectional observation using a TEM will be described later).

[0070] Here, the phrase "repeating cells with a stack ratio (A / B) and a stack ratio (C / B) of 0.8 or higher and 1.3 or lower relative to all repeating cells constitute 80% or higher and 100% or lower" means that repeating cells with both A / B and C / B ratios of 0.8 or higher and 1.3 or lower constitute 80% or higher and 100% or lower relative to all repeating cells. The preferred range described later can be interpreted similarly. The phrase "dielectric constant X" here... i "In descending order of layer A, layer B, and layer C" refers to the dielectric constant X of layer A. A The dielectric constant X of layer B B More than 2% larger, and the dielectric constant X of layer B. B The dielectric constant X of the C layer C More than 2% (the same applies to the first multilayer film of the present invention).

[0071] From the same perspective, it is important that in the first multilayer film of the present invention, the layers are ordered sequentially from the layer with the largest dielectric constant X as layer A, layer B, and layer C. Furthermore, from the same perspective, it is preferable that in the first multilayer film of the present invention, the percentage of repeating units in which the total thickness ratio (A / B) of layer A to layer B and the total thickness ratio (C / B) of layer C to layer B are 0.8 or more and 1.3 or less, is 80% or more and 100% or less relative to all repeating units. The preferred ranges described below are also the same.

[0072] The reflection generated by the multilayer laminated film, in the case of the multilayer laminated film of the present invention, is determined based on the previously described formula (A). In the case of the multilayer laminated film obtained by alternately laminating two different layers formed of thermoplastic resin, as in Patent Document 3, the reflection wavelength is determined based on formula (B). The multilayer laminated film not only reflects the wavelength of this reflection (first reflection), but also reflects half the wavelength (second reflection), one-third the wavelength (third reflection), one-quarter the wavelength (fourth reflection), one-fifth the wavelength (fifth reflection), ..., one-n wavelength (nth reflection) (n is an integer).

[0073]

[0074] Here, λ is the reflected wavelength, and n A Let d be the in-plane refractive index of layer A. A Let n be the thickness of layer A. B Let d be the in-plane refractive index of layer B. B The thickness of layer B.

[0075] Typically, reflections of 1 / n wavelength occur in multilayer films. Therefore, if a multilayer film is designed to reflect near-infrared light, for example, at a wavelength of 1000 nm, it will also reflect visible light at half its wavelength, i.e., 500 nm, sometimes resulting in reduced transparency and coloration. To address this issue, Patent Document 3 suppresses half-wavelength reflection by setting the thickness ratio of adjacent A layers to B layers in the range of 0.9 to 1.1. However, the method shown in Patent Document 3 can only suppress reflections up to half the wavelength. Therefore, if near-infrared light above 1200 nm is reflected, the 1 / 3 wavelength is 400 nm or more, which is visible light, thus causing reduced transparency and coloration in the multilayer film. Therefore, there are limitations in expanding the near-infrared reflection band while maintaining high transmittance and transparency in the visible light region.

[0076] In contrast, the multilayer laminated film of the present invention uses a repeating unit structure formed by arranging three resin layers (layer A, layer B, and layer C) with different dielectric constants X in the order of layer A / layer B / layer C / layer B. Within this repeating unit, repeating units with a stacking ratio (A / B) of the total thickness of layer A relative to layer B and a stacking ratio (C / B) of the total thickness of layer C relative to layer B of 0.8 or more and 1.3 or less, respectively, account for 80% or more and 100% or less of all repeating units. Furthermore, the dielectric constant X decreases in the order of layer A, layer B, and layer C, thereby suppressing reflection over a wide wavelength range from 1 / 2 wavelength to 1 / 4 wavelength. Thus, the multilayer laminated film of the present invention can suppress reflection up to 1 / 4 wavelength, thereby mitigating the deterioration of transparency and coloring while reducing reflection of near-infrared light up to wavelength 2000 nm (1 / 5 wavelength of reflection occurs at 400 nm, which does not affect the transparency of visible light).

[0077] By setting the stack ratios (A / B) and (C / B) to be greater than 0.8 and less than 1.3, the phases of the half-wavelength to quarter-wavelength wavelengths reflected at the interfaces between layers within the repeating unit structure become out of phase, producing a cancellation effect and suppressing higher-order reflections. Furthermore, by decreasing the dielectric constant X in the order of layer A, layer B, and layer C, the amplitudes of the half-wavelength to quarter-wavelength wavelengths reflected at the interfaces between layers become the same, thus strengthening the cancellation effect.

[0078] The reflectivity from 1 / 2 wavelength to 1 / 4 wavelength is affected not only by the stack ratio (A / B) and stack ratio (C / B), but also by the refractive index difference, the number of repeating units, and the layer thickness distribution of the multilayer film. Therefore, it cannot be determined solely by the stack ratio (A / B) and stack ratio (C / B). However, by making the phases of the 1 / 2 wavelength to 1 / 4 wavelength reflected at the interfaces between the layers in the repeating unit structure closer to anti-phase, the cancellation effect is improved, thereby mitigating the deterioration of transparency and coloration. From the above perspective, in the multilayer film of the present invention, within a wide range of multilayer film designs, a stack ratio (A / B) of 0.8 or higher and 1.1 or lower, and a stack ratio (C / B) of 0.9 or higher and 1.2 or lower are more preferable. That is, more preferably, the repeating units with a stack ratio (A / B) of 0.8 or more and 1.1 or less, and the repeating units with a stack ratio (C / B) of 0.9 or more and 1.2 or less, account for 80% or more and 100% or less of all repeating units.

[0079] By setting the stack ratio (A / B) and stack ratio (C / B) to 0.8 or higher and 1.3 or lower, or within the aforementioned preferred range, high-order reflections occurring in the visible light band can be suppressed, thus achieving high transmittance and transparency of visible light. From this perspective, the proportion of repeating units with stack ratios (A / B) and stack ratios (C / B) of 0.8 or higher and 1.3 or lower, or within the aforementioned preferred range, is preferably 90% or higher, more preferably 95% or higher, in all repeating units. It should be noted that the theoretical upper limit of this proportion is 100%.

[0080] Furthermore, the dielectric constant X decreasing in the order of layer A, layer B, and layer C refers to the in-plane refractive index decreasing in the order of layer A, layer B, and layer C. Preferably, when the in-plane refractive indices of layer A, layer B, and layer C are set to Na, Nb, and Nc respectively, Nb preferably satisfies (Na × Nc). 1 / 2 ×0.99≤Nb≤(Na×Nc) 1 / 2 ×1.01, the optimal choice satisfies Nb=(Na×Nc) 1 / 2 By having the above-mentioned Nb values, the reflection cancellation effect of each wavelength from 1 / 2 to 1 / 4 wavelength is strong, and the multilayer film will have both high near-infrared reflection and high colorless transparency when viewed from the front.

[0081] As described above, the second multilayer film of the present invention is configured to reflect near-infrared light in the wavelength range of 850nm to 2000nm while also possessing high transmittance and transparency of visible light. The multilayer film is configured as follows: a repeating unit structure consisting of three resin layers (layer A, layer B, and layer C) with different dielectric constants X arranged in the order of layer A / layer B / layer C / layer B. The units with a total layer thickness of 250nm or more and 630nm or less within the repeating units account for 80% or more and 100% or less of all repeating units. The repeating units with a stack ratio (A / B) and a stack ratio (C / B) of 0.8 or more and 1.3 or less within the repeating units account for 80% or more and 100% or less of all repeating units. The dielectric constant X decreases in the order of layer A, layer B, and layer C as described above.

[0082] Furthermore, the second multilayer film of the present invention requires that the average visible light reflectance of P-waves incident at an angle of 60° relative to the normal to the film surface be 10% or more and 99% or less. This requirement is preferably also satisfied in the first multilayer film of the present invention, and the preferred range described below is the same. It should be noted that the angle between the incident light and the normal to the film surface is sometimes referred to as the incident angle. The reflectance (%) of P-waves can be determined by measuring the reflectance of P-waves in the wavelength range of 400 to 700 nm at an incident angle θ = 60° using a spectrophotometer at 1 nm intervals and calculating the average value.

[0083] In the case of typical transparent substrates such as transparent glass and transparent resin films, as the incident angle gradually increases from 20° relative to the normal of the film surface, the reflectivity of P-waves, which are polarized light, decreases. At the angle known as the Brewster angle, the reflectivity of P-waves is 0%. That is, for typical transparent substrates, it is difficult to transmit P-waves from the front direction and reflect P-waves from the tilted direction. On the other hand, from the viewpoint of improving image display quality, it is preferable to have a high average reflectivity of P-waves with wavelengths of 400nm to 700nm incident at an incident angle of 60°, preferably 20% or more, and more preferably 25% or more. It should be noted that there is no particular upper limit to the average reflectivity of P-waves with wavelengths of 400nm to 700nm incident at an incident angle of 60°, but from the viewpoint of feasibility, it is 99%. In addition, when the background and image are superimposed through the background, this average reflectivity is preferably 50% or less.

[0084] P-waves and S-waves can be defined as follows. When electromagnetic waves (light) are incident from an oblique direction relative to the surface of an object, a P-wave refers to an electromagnetic wave with its electric field component parallel to the incident surface (linearly polarized light vibrating parallel to the incident surface), and an S-wave refers to an electromagnetic wave with its electric field component perpendicular to the incident surface (linearly polarized light vibrating perpendicular to the incident surface). The reflection characteristics of P-waves and S-waves are explained with reference to the accompanying diagram. Figure 3 (a) refers to conventional transparent resin films (typically transparent supports). Figure 3 (b) represents a multilayer film representing the previously reflected light. Figure 3 (c) refers to a multilayer film that transmits visible light and reflects near-infrared light. Figure 3 (d) is a graph (example) showing the angular dependence of the average reflectance at wavelengths of 400 nm to 700 nm for P-wave and S-wave light incident on each film from air at wavelengths of 400 nm to 700 nm regarding the multilayer laminated films of the present invention. It should be noted that... Figure 3 The symbols 20 and 21 in the middle represent the reflectivity 20 of the P-wave and the reflectivity 21 of the S-wave, respectively.

[0085] like Figure 3 As shown in (a), according to Fresnel's formula, the reflectivity of P-waves in a typical transparent support tends to decrease with increasing incident angle, then increase again after reaching 0%. On the other hand, the reflectivity of S-waves increases with increasing incident angle. Figure 3 As shown in (b), conventional multilayer films for reflecting light have low transmittance because both P-waves and S-waves have a certain reflectivity at an incident angle of 0°. Furthermore, the reflectivity of both P-waves and S-waves increases with increasing incident angle. Figure 3As shown in (c), conventional multilayer films that transmit visible light and reflect near-infrared light, similar to typical transparent supports, exhibit a tendency for P-wave reflectance to decrease with increasing incident angle, reach near 0%, and then increase again. On the other hand, S-wave reflectance increases with increasing incident angle. Figure 3 As shown in (d), the multilayer film of the present invention has the following characteristics: low reflectivity (high transmittance) for both P-waves and S-waves at an incident angle of 0°, and increasing reflectivity for both P-waves and S-waves as the incident angle increases. By using a multilayer film with such optical properties, for example, in a projection image display component, good background visibility can be obtained when viewing the background through the projection image display component from a direction perpendicular to the surface of the projection image display component, and good display performance of the projected image can be obtained when projecting an image of P-waves onto the surface of the projection image display component.

[0086] The principle behind the multilayer laminated film of the present invention, which exhibits high transmittance and transparency of visible light from the front direction while reflecting P-waves in the tilted direction, will be explained. The multilayer laminated film of the present invention reflects near-infrared light over a wide wavelength range while suppressing reflection of 1 / 2 to 1 / 4 of the near-infrared reflection wavelength. Here, this is achieved by making the in-plane refractive index Nb of layer B approximately equal to Nb = (Na × Nc). 1 / 2 This improves the cancellation effect of reflections from 1 / 2 wavelength to 1 / 4 wavelength. The multilayer film of this invention is designed such that the in-plane refractive index Nb of layer B in the front direction is close to Nb = (Na × Nc). 1 / 2 In the tilt direction, the oblique refractive index Nbθ ≠ (Naθ × Ncθ) of layer B. 1 / 2 .

[0087] Here, Naθ, Nbθ, and Ncθ represent the refractive indices of layers A, B, and C, respectively, for 633 nm wavelength light entering the multilayer film from air at an incident angle θ (°). In this invention, the oblique refractive index Nbθ of layer B in the tilted direction of the multilayer film is ≠ (Naθ × Ncθ). 1 / 2 Therefore, the cancellation effect of reflections in the 1 / 2 to 1 / 4 wavelength range in the tilt direction is weak. It should be noted that this weak cancellation effect in the tilt direction only applies to P-waves, not S-waves. Therefore, the multilayer film of the present invention reflects P-waves corresponding to the visible light region in the 1 / 2 to 1 / 4 wavelength range in the tilt direction, thus enabling an average visible light reflectance of P-waves incident at an angle of 60° relative to the normal to the film surface to be 10% or more. It should be noted that although the transparency in the tilt direction is slightly reduced due to the reflection of P-waves in the tilt direction, a film with sufficiently high transparency in the front (0° incident angle) direction can be obtained.

[0088] As described above, the multilayer laminated film of the present invention has a unit structure arranged in the order of layer A / layer B / layer C / layer B, and the layer thickness, lamination ratio, and refractive index within the unit structure are controlled within the aforementioned range. Therefore, a single multilayer laminated film can transmit visible light in the front direction while being transparent, and simultaneously possess near-infrared reflection and reflection of P-wave visible light in the tilted direction. The multilayer laminated film of the present invention achieves the functions required by existing technologies that require laminating two types of multilayer laminated films with a single sheet, demonstrating a particularly significant advantage in this regard. Films obtained by laminating two types of multilayer laminated films often suffer from wrinkles during high-temperature processing due to differences in the thermal shrinkage characteristics of the multilayer laminated films. The multilayer laminated film of the present invention also has the advantage of solving such problems.

[0089] From the viewpoint that the average visible light reflectance of P-waves incident at an angle of 60° relative to the normal to the film surface is 10% or more, the second multilayer laminated film of the present invention is preferably composed of a combination of crystalline / amorphous / amorphous thermoplastic resin layers, with layers A, B, and C being crystalline / amorphous / amorphous, respectively. For the above reasons, the first multilayer laminated film of the present invention needs to be composed of a combination of crystalline / amorphous / amorphous thermoplastic resin layers, with layers A, B, and C being crystalline / amorphous / amorphous, respectively. Here, "composed of a combination of crystalline / amorphous / amorphous thermoplastic resin layers, with layers A, B, and C being crystalline / amorphous / amorphous thermoplastic resin layers" means that the main component of layer A is a crystalline thermoplastic resin, and the main components of layers B and C are amorphous thermoplastic resins. The term "main component" refers to a component included at 80% to 100% by mass when all components constituting the layers are set to 100% by mass. Furthermore, the term "crystallinity" here refers to a melting enthalpy (ΔHm) of 5 J / g or higher as measured by JIS-K-7122 (2012), while "amorphous" refers to a melting enthalpy (ΔHm) of less than 5 J / g. Stronger amorphousness better suppresses the decrease in planar refractive index; therefore, a melting enthalpy (ΔHm) of less than 3 J / g is preferred, and even more preferred is less than 1 J / g or the melting curve (melting enthalpy curve) and melting point (Tm) not being observable.

[0090] The following uses Figure 4 This explains the effect of the multilayer film as such a scheme. Figure 4 The refractive index of the multilayer films in Example 1 and Comparative Example 1 (both described later) is shown relative to the incident angle of P-wave light incident on layers A, B, and C. Figure 4 The symbols 22 to 25 in the figure represent, in turn: the refractive index of layer A at the incident angle θ (Naθ), the refractive index of layer C at the incident angle θ (Ncθ), the refractive index of layer B of the multilayer film of the present invention (Example 1) at the incident angle θ (Nbθ), and the refractive index of layer B of the conventional near-infrared reflective multilayer film (Comparative Example 1) at the incident angle θ (Nbθ).

[0091] The thermoplastic resin used in layer A is crystalline, and its refractive index is lower in the direction perpendicular to the plane than in the in-plane direction. Therefore, the refractive index decreases as the incident angle increases. The thermoplastic resin used in layer C is amorphous, and its refractive index is the same in the in-plane direction and in the direction perpendicular to the plane. Therefore, the refractive index does not change even if the incident angle changes. The refractive index of the front side (in-plane direction, incident angle 0°) of layer B used in Example 1 and Comparative Example 1 is the same value, since Nb≒(Na×Nc) 1 / 2 The value of the film is such that the reflection cancellation effect is strong from 1 / 2 wavelength to 1 / 4 wavelength. The multilayer film exhibits high transmittance for visible light incident from the front direction, thus possessing excellent transparency.

[0092] The thermoplastic resin in layer B used in Comparative Example 1 is crystalline, and its refractive index differs between the in-plane direction and the direction perpendicular to the plane. Therefore, as... Figure 4 As shown, the refractive index decreases as the incident angle of light increases, since Nbθ≒(Naθ×Ncθ) is also taken in the tilt direction. 1 / 2 The value of is such that it does not reflect visible light. On the other hand, the thermoplastic resin of layer B used in Example 1 of the multilayer laminated film of the present invention is amorphous, and its refractive index in the in-plane direction is basically the same as that in the direction perpendicular to the plane. Therefore, even if the incident angle changes, the refractive index does not change, such as Figure 4 As shown, since Nbθ≠(Naθ×Ncθ) in the tilt direction... 1 / 2 The value of this value results in the reflection of P-waves at a wavelength of 1 / 2 to 1 / 4 of the wavelength, thereby enabling an average visible light reflectance of over 10% when incident at an angle of 60° relative to the normal to the film surface. Furthermore, the average visible light reflectance when incident at an angle of 60° relative to the normal to the film surface is also affected by the number of repeating units. Therefore, if the resin composition of each layer is the same, increasing the number of repeating units further improves the average visible light reflectance.

[0093] Furthermore, using Figure 5 The differences in the average visible light reflectance of P-waves due to the different refractive indices of the B layer will be explained above. Figure 5The symbol 26 represents the average visible light reflectance of the P-wave in the multilayer film of the present invention (Example 1), and the symbol 27 represents the average visible light reflectance of the P-wave in the prior art near-infrared reflective multilayer film (Comparative Example 1). The prior art (Comparative Example 1) shows a tendency for the average visible light reflectance 27 of the P-wave to decrease from an incident angle of 0° towards 50° and to increase from an incident angle of 60°. However, at an incident angle of 60°, it exhibits a low value indicating that the P-wave image cannot be sufficiently displayed. On the other hand, the multilayer film of the present invention shows a very slight decrease in the average visible light reflectance 26 of the P-wave from an incident angle of 0° towards 20°, but a tendency for the average visible light reflectance 26 of the P-wave to increase after an incident angle of 20°, exhibiting a value at an incident angle of 60° that allows for sufficient display of the P-wave image. As described above, by using a combination of crystalline / amorphous / amorphous thermoplastic resin layers A, B, and C respectively, it is easy to achieve an average visible light reflectance of 10% or more for P-waves when incident at an angle of 60° relative to the normal of the film surface.

[0094] As another preferred embodiment, when the multilayer film of the present invention is incident at an angle of 60° with respect to the normal of the film surface, the average visible light reflectance of P-waves is 10% or more, and examples include an orientation factor of layer A of 0.06 or more, and a dielectric constant X of layer B. B A scheme where the ratio of the dielectric constant in the in-plane direction to that in the direction perpendicular to the plane is 10% or less. The ratio of the dielectric constant in the in-plane direction to that in the direction perpendicular to the plane is the difference between the dielectric constant in the in-plane direction and the dielectric constant in the direction perpendicular to the plane, divided by the ratio (%) of the dielectric constant in the direction perpendicular to the plane. Hereinafter, we will use... Figure 4 The effects of this scheme are explained. The plane orientation factor is defined as (in-plane refractive index) - (direct plane refractive index), representing the difference in refractive index between the in-plane direction and the direction perpendicular to the plane. With a plane orientation factor of 0.06 or higher through layer A, thus... Figure 4 As shown in Figure 22, the refractive index can vary greatly depending on the incident angle of 0° and the tilt direction. The relationship between the refractive index n and the dielectric constant X is given by "n = (X / X0 × μ / μ0)". 1 / 2 The expression "n = (X / X0)" indicates that X0 is the permittivity of vacuum, μ is the permeability of magnetic field, and μ / μ0 is considered to be 1 in a wide range of resins in the visible to near-infrared range. Therefore, it becomes "n = (X / X0)". 1 / 2 The ratio of the dielectric constant in the in-plane direction to that in the direction perpendicular to the plane of layer B can be considered as related to the ratio of the refractive index.

[0095] The dielectric constant of layer B is X B The ratio of the dielectric constant in the in-plane direction to that in the direction perpendicular to the plane is less than 10%, meaning that the difference in refractive index between the in-plane direction and the direction perpendicular to the plane in layer B is small, and Nbθ and (Naθ×Ncθ) are similar.1 / 2 The difference is large, and reflection of P-waves at 1 / 2 to 1 / 4 wavelength occurs. From the viewpoint of improving the average visible light reflectivity of P-waves when incident at an angle of 60° relative to the normal to the film surface, the planar orientation factor of layer A is more preferably 0.12 or higher, and even more preferably 0.18 or higher, and the dielectric constant X of layer B... B The ratio of the dielectric constant in the in-plane direction to the dielectric constant in the direction perpendicular to the plane is more preferably 5% or less, and even more preferably the ratio of the dielectric constant X of layer B in the in-plane direction to the dielectric constant in the direction perpendicular to the plane is 3% or less.

[0096] The planar orientation coefficient of layer A refers to the planar orientation coefficient of layer A measured at a wavelength of 633 nm, and the measurement method will be described later. The ratio of the dielectric constant of the in-plane direction to the dielectric constant of the direction perpendicular to the plane of layer B can be determined by electron energy loss spectroscopy (EELS measurement), and the details of the measurement method will be described later.

[0097] Furthermore, as a method for achieving an orientation factor of 0.06 or higher for layer A of a multilayer laminated film and a dielectric constant X of layer B in which the ratio of the dielectric constant in the in-plane direction to that in the direction perpendicular to the plane is 10% or less, it is preferable to use a crystalline resin for layer A and stretch it at least twice in at least one direction at a temperature above its glass transition temperature. More preferably, it is stretched at least three times in one direction and in a direction orthogonal to that direction within the film surface. In this case, for layer B, it is preferable to use an amorphous resin, or to perform heat treatment at a temperature above the melting point of layer B during the film-forming heat treatment process. Particularly from the viewpoint that the heat treatment temperature can be arbitrarily selected, it is more preferable to use an amorphous resin.

[0098] The resin layer used in the multilayer laminated film of the present invention is preferably a thermoplastic resin. The thermoplastic resin may include the following resins: chain polyolefins such as polyethylene, polypropylene, poly(4-methylpentene-1), and polyacetal; ring-opening metathesis polymers of norbornene; addition polymers; alicyclic polyolefins that are addition copolymers with other olefins; biodegradable polymers such as polylactic acid and polybutylene succinate; polyamides such as nylon 6, nylon 11, nylon 12, and nylon 66; aromatic polyamides; polymethyl methacrylate; polyvinyl chloride; polyvinylidene chloride; polyvinyl alcohol; polyvinyl butyral; and ethylene glycol. Polyesters including vinyl acetate copolymer, polyacetal, polyglycolic acid, polystyrene, styrene copolymer, polymethyl methacrylate, polycarbonate, polypropylene terephthalate, polyethylene terephthalate, polybutylene terephthalate, polyethylene 2,6-naphthalenedicarboxylate, etc.; polyethersulfone, polyetheretherketone, modified polyphenylene ether, polyphenylene sulfide, polyetherimide, polyimide, polyarylate, tetrafluoroethylene resin, trifluoroethylene resin, trifluorochloroethylene resin, tetrafluoroethylene-hexafluoropropylene copolymer, polyvinylidene fluoride, etc.

[0099] Among these, polyester and polymethyl methacrylate are particularly preferred from the viewpoints of strength, heat resistance, transparency, refractive index difference, and versatility. They can be copolymers or mixtures of two or more resins.

[0100] Polyester is a resin having a molecular structure in which dicarboxylic acid units and diol units are linked by ester bonds. Preferably, polyesters are those whose main structural units are aromatic or aliphatic dicarboxylic acid units and diol units. Here, the term "main structural unit," if referring to a dicarboxylic acid unit, means a dicarboxylic acid unit that is contained at a rate of more than 50 mol% and less than 100 mol% when all dicarboxylic acid units constituting the polyester are considered to be 100 mol%. The same interpretation applies to the main structural units within diol units.

[0101] Examples of aromatic dicarboxylic acids constituting polyesters include, for example, terephthalic acid, isophthalic acid, phthalic acid, 1,4-naphthalenedicarboxylic acid, 1,5-naphthalenedicarboxylic acid, 2,6-naphthalenedicarboxylic acid, 4,4'-diphenyldicarboxylic acid, 4,4'-diphenyl ether dicarboxylic acid, and 4,4'-diphenyl sulfone dicarboxylic acid. Examples of aliphatic dicarboxylic acids include, for example, adipic acid, octanoic acid, sebacic acid, dimer acids, dodecanoic acid, cyclohexanedicarboxylic acid, and their ester derivatives. Among these, terephthalic acid and 2,6-naphthalenedicarboxylic acid, which exhibit high refractive indices, are preferred. These acid components may be used in combination with only one type or in two or more types, and furthermore, a portion of hydroxy acids such as hydroxybenzoic acid may be copolymerized.

[0102] In addition, examples of diol components include ethylene glycol, 1,2-propanediol, 1,3-propanediol, neopentyl glycol, 1,3-butanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,2-cyclohexanediethanol, 1,3-cyclohexanediethanol, 1,4-cyclohexanediethanol, diethylene glycol, triethylene glycol, polyalkylene glycol, 2,2-bis(4-hydroxyethoxyphenyl)propane, isosorbide, and spirocyclohexanediol. Polyalkylene glycol and ethylene glycol are preferred. Only one of these diol components may be used, or two or more may be used in combination.

[0103] The thermoplastic resin that forms the main component of each layer of the multilayer laminated film of the present invention, for example, the polyesters described above, is preferably selected from polyethylene terephthalate and its polymers, polyethylene naphthalate and its copolymers, polybutylene terephthalate and its copolymers, polybutylene naphthalate and its copolymers, and further polyhexyl terephthalate and its copolymers, polyhexyl naphthalate and its copolymers, and polymethyl methacrylate and its copolymers.

[0104] In addition, various additives, such as antioxidants, heat stabilizers, weather stabilizers, UV absorbers, organic slip agents, pigments, dyes, organic or inorganic microparticles, fillers, antistatic agents and nucleating agents, can be added individually or in combination to thermoplastic resins to a degree that does not deteriorate their properties.

[0105] The multilayer film of the present invention preferably has a chroma of 10 or less when the transmitted light incident perpendicularly to the film surface. To achieve a chroma of 10 or less in the transmitted light incident perpendicularly to the film surface, it is effective to ensure strong cancellation of reflections at each wavelength from 1 / 2 to 1 / 4 of the wavelength, and to achieve uniform reflection throughout the near-infrared reflection wavelength region. To ensure strong cancellation of reflections at each wavelength from 1 / 2 to 1 / 4 of the wavelength, it is preferable, as described above, that the stack ratio (A / B) is 0.8 or more and 1.3 or less (preferably 0.8 or more and 1.1 or less), the stack ratio (C / B) is 0.8 or more and 1.3 or less (preferably 0.9 or more and 1.2 or less), and that when the in-plane refractive indices of layers A, B, and C are respectively set to Na, Nb, and Nc, Nc satisfies (Na × Nc). 1 / 2 ×0.99≤Nb≤(Na×Nc) 1 / 2 ×1.01. In addition, the fact that the number of cells with a total layer thickness of 250 nm or more and 630 nm or less in the repeating cells is 80% or more relative to all repeating cells, or the above-mentioned preferred range, is also related to the fact that no primary reflection or higher-order reflection occurs in the visible light band, and is therefore effective.

[0106] By ensuring that the chroma of the transmitted light incident perpendicular to the film surface is less than 10, background shading can be suppressed when observing the background through the multilayer laminated film of this invention, thereby improving background visibility. It should be noted that the chroma of the transmitted light can be calculated as follows: Based on JIS-Z-8781-3 (2016), the tristimulus values ​​X, Y, Z of the CIE1931 color system and the tristimulus values ​​Xn, Yn, Zn of specific white light are calculated. From the obtained X, Y, Z and Xn, Yn, Zn, the a* and b* values ​​of the CIE1976 L*a*b* color space are obtained based on JIS-Z-8781-4 (2013), and calculated as the square root of the sum of the squares of a* and b*.

[0107] The multilayer laminated film of the present invention preferably has a transmittance of visible light incident perpendicularly to the film surface of 70% or more and 100% or less. Specifically, "a transmittance of visible light incident perpendicularly to the film surface (meaning an angle of 0° relative to the normal of the multilayer laminated film surface) of 70% or more and 100% or less" means that the average transmittance of light with wavelengths of 400-700 nm incident perpendicularly to the multilayer laminated film of the present invention is 70% or more and 100% or less. Furthermore, the visible light referred to here is not the aforementioned P-wave visible light, but includes both P-waves and S-waves. This high transmittance of light in the visible light region of 400-700 nm provides transparency similar to transparent glass or transparent resin films, allowing for good visibility of the background when observing it from a direction perpendicular to the multilayer laminated film surface. From this perspective, this transmittance is preferably 80% or more, more preferably 90% or more. If the transmittance is 90% or more, the user can view the background without perceiving the presence of the multilayer laminated film. It should be noted that, from the viewpoint of ease of implementation, the upper limit of this transmittance is preferably 99%.

[0108] The transmittance of light incident perpendicular to the surface of a multilayer film can be determined by using a spectrophotometer to measure the transmittance of light with wavelengths of 400-700 nm at an incident angle θ=0° at 1 nm intervals, and then calculating the average value.

[0109] The method for achieving a transmittance of visible light incident perpendicularly to the film surface of the multilayer laminated film of the present invention of 70% or more and 100% or less will be described. The multilayer laminated film of the present invention achieves this by having at least 80% of the repeating units having a total layer thickness of 250 nm or more and 630 nm or less, thereby reflecting only near-infrared light (first reflection). Furthermore, by having at least 80% of the repeating units having a stacking ratio (A / B) of the total thickness of layer A relative to layer B and a stacking ratio (C / B) of the total thickness of layer C relative to layer B of 0.8 or more and 1.3 or less, and by having a dielectric constant X decreasing in the order of layer A, layer B, and layer C, reflections of wavelengths from 1 / 2 to 1 / 4 of the first reflection wavelength can be canceled. With this configuration, it is easy to achieve a transmittance of visible light incident perpendicularly to the film surface of 70% or more and 100% or less.

[0110] The multi-layer laminated film of the present invention preferably has a reflectivity of 40% or more in a wavelength range of at least 100 nm in the wavelength range of 850 nm to 1600 nm when light is incident on the film surface at an angle of 10° with respect to the normal of the film surface. By having a reflectivity of 40% or more in a wavelength range of at least 100 nm in the wavelength range of 850 nm to 1600 nm, when the multi-layer laminated film of the present invention is used for window members of automobiles and buildings, it is possible to reflect the near-infrared energy of the sun invading into the vehicle interior or the room interior and suppress the temperature rise in the vehicle interior or the room interior. From the viewpoint of improving the suppression effect of the temperature rise in the vehicle interior or the room interior, it is more preferable that the reflectivity is 40% or more in a wavelength range of at least 600 nm in the wavelength range of 850 nm to 1600 nm. It should be noted that the reflectivity at each wavelength can be measured using a well-known spectrophotometer.

[0111] As a method for achieving a reflectivity of 40% or more in a wavelength range of at least 100 nm in the wavelength range of 850 nm to 1600 nm, there can be cited a scheme in which the total layer thickness in the repeating unit is 250 nm or more and the number of repeating units is 15 or more with a thickness of 630 nm or less, and the in-plane refractive index difference between layer A and layer B and between layer B and layer C is 0.03 or more. From the viewpoint of increasing the reflectivity with a smaller number of repeating units, the in-plane refractive index difference between layer A and layer B and between layer B and layer C is both 0.07 or more, and more preferably both are 0.10 or more. From the same viewpoint, the in-plane refractive index difference between layer A and layer C is preferably 0.06 or more, more preferably 0.14 or more, and further preferably 0.20 or more.

[0112] The multi-layer laminated film of the present invention preferably satisfies the relationship of Rp20 ≤ Rp40 < Rp60 when the average reflectivities of the P-wave in the visible light band incident on the film surface at angles of 20°, 40°, and 60° with respect to the normal of the film surface are set as Rp20 (%), Rp40 (%), and Rp60 (%) in turn. Such a scheme is a scheme that does not have an angle equivalent to the Brewster angle. Therefore, by making the multi-layer laminated film of the present invention such a scheme, it is easy to make the reflectivity of the P-wave incident from an inclined direction of the multi-layer laminated film relatively higher than the reflectivity of the P-wave incident from the front, and when using a light source emitting P-wave as a light source for irradiating an image, the image can be projected more clearly. It should be noted that the average reflectivity of the P-wave in the wavelength range of 400 to 700 nm can be measured by measuring the reflectivity of the P-wave in this wavelength band at 1 nm intervals using a spectrophotometer and calculating its average value (the detailed content of the measurement method will be described later).

[0113] In order to satisfy the relationship of Rp20 ≤ Rp40 < Rp60, the following solution is effective. The solution is composed of a combination of a thermoplastic resin layer with A layer, B layer, and C layer being crystalline / amorphous / amorphous respectively; the number of repeating units is 90 or more; the surface orientation coefficient of the A layer is 0.18 or more, and the ratio of the dielectric constant in the in-plane direction to the dielectric constant in the direction perpendicular to the plane in the dielectric constant X of the B layer is 10% or less. These methods can be appropriately combined. By using the above methods, as Figure 4 shown, as the incident angle increases from 0° to the inclined direction, the difference between Nbθ and (Naθ × Ncθ) 1 / 2 becomes larger. That is, as the incident angle increases from 0° to the inclined direction, the reflection of P waves with wavelengths from 1 / 2 wavelength to 1 / 4 wavelength becomes stronger, and it is easy to satisfy Rp20 ≤ Rp40 < Rp60.

[0114] The multilayer laminate film of the present invention preferably has a chroma of 20 or less for the reflected light of P waves incident at an angle of 60° with respect to the normal of the film surface, and more preferably 5 or less. Hereinafter, the "chroma of the reflected light of P waves when incident at an angle of 60° with respect to the normal of the multilayer laminate film surface" is sometimes referred to as the "chroma of the reflected light of P waves". A chroma of 20 or less for the reflected light of P waves means that uniform reflection can be achieved throughout the visible light wavelength region. By adopting such a solution, coloring caused by the reflected light can be suppressed. Therefore, when the multilayer laminate film is used as a projection member such as a projection image display device, when the projection image is projected using P waves, the color of the projection image displayed is reproduced in substantially the same color as the image irradiated from the display.

[0115] Use Figure 6 To illustrate an example of a method for making the chroma of the reflected light of P waves 20 or less. Figure 6 An example of the ideal layer thickness distribution of the A layer, B layer, and C layer from the layer position 1 on the film surface to the layer position 601 on the opposite film surface is shown, Figure 6 and the symbols 28 to 30 in it successively represent the thickness of the A layer, the thickness of the C layer, and the thickness of the B layer. As Figure 6 shown, based on formula (A), by uniformly arranging the thicknesses of the A layer, B layer, and C layer in the range of the reflection wavelength from 850 nm to 1750 nm, the standard deviation of the reflectance in this wavelength band can be made 10% or less, and the standard deviation of the reflectance in each wavelength band from 1 / 2 wavelength to 1 / 4 wavelength in the visible light region, which is the reflection band, can also be made 10% or less. As a result, it is easy to make the chroma of the reflected light of P waves 20 or less.

[0116] In the film formation of the multilayer laminate film, in practice, it is affected by factors such as the design accuracy of the device and the operation stability of the film-forming device, resulting in Figure 6Such an ideal layer thickness error is acceptable, but as long as the average error of the position of each layer from layer position 1 to layer position 601 is within ±10%, the chroma of the P-wave reflected light can be 20 or less. A method for suppressing this thickness error will be explained. Three thermoplastic resins are melted separately, and multiple repeating units arranged in the order of layer A / layer B / layer C / layer B are stacked using a stacking device. The molten stack is then melt-extruded into a sheet using a T-die or the like, resulting in a multilayer stacked structure. Suppressing the layer disorder of this molten stack is related to suppressing the thickness error. One method is to provide a thick layer on the outermost surface of the molten stack. The thickness of this outermost layer is preferably 1% or more, more preferably 4% or more, relative to the overall thickness of the molten stack. Furthermore, it is more preferable to make the thickness of two outermost layers thicker than just one outermost layer.

[0117] Furthermore, to ensure that the chroma of the reflected P-wave light is below 20 and to achieve uniform reflection across the entire visible light wavelength range, it is preferable that the wavelength range in which the reflectivity is 40% or higher when the light is incident on the film surface at an angle of 10° to the normal to the film surface includes at least the range of 850 nm and below. This is because the reflected wavelength of a P-wave incident at an angle of 60° to the normal to the film surface is in the range of 1 / 2 to 1 / 4 of the primary reflection wavelength. Therefore, when the primary reflection wavelength band is narrow, the reflection band of 1 / 2 to 1 / 4 of the primary reflection wavelength is also narrowed, thus reflecting only a portion of the wavelength in the visible light region, resulting in higher chroma of the reflected P-wave light.

[0118] The multilayer film of the present invention preferably has an azimuth deviation of Rp60 (%) when the average reflectance is set to Rp60 (%) when a P-wave in the visible light band is incident on the film surface at an angle of 60° with the normal to the film surface. Here, azimuth is referred to as... Figure 7 As shown, this refers to the azimuth angles (0°, 45°, 90°, 135°, 180°) within the surface of the multilayer laminated film 4 constituting the laminate of the present invention, when the azimuth angle of the main orientation axis direction is set to 0°. The main orientation axis direction refers to the direction with the greatest orientation degree within the film surface. It should be noted that the orientation degree can be measured using a known molecular orientation meter, such as the MOA-7015 molecular orientation meter from Oji Keiseki Kogyo Co., Ltd. The azimuth angle deviation refers to the difference between the maximum and minimum values ​​of Rp60(0°), Rp60(45°), Rp60(90°), Rp60(135°), and Rp60(180°) measured at the above azimuth angles (0°, 45°, 90°, 135°, 180°).

[0119] Rp60(0°), Rp60(45°), Rp60(90°), Rp60(135°), Rp60(180°) can be measured by using a spectrophotometer to measure the reflectance of the P wave at wavelengths from 400 to 700 nm at an incident angle θ = 60° at 1 nm intervals and finding their average values. Here, as the azimuth angle of the tilt direction, the azimuth angle of the main orientation axis direction of the multilayer film is taken as 0°, and based on this, 0°, 45°, 90°, 135°, and 180° are rotated to the right, and these 5 are adopted. By making the azimuth angle deviation of Rp60 less than 10%, the display properties such as the brightness of this information can be maintained at the same level regardless of the azimuth of the projected image.

[0120] In order to make the azimuth angle deviation of Rp60 small, for example, it can be cited that the refractive index unevenness in the in-plane direction of the multilayer film of the present invention is small. In order to make the refractive index unevenness in the in-plane direction of the film small, it can be cited that when the film is biaxially stretched, the stretching is performed in such a way that the difference in the orientation states in the film length direction and the film width direction is small. The stretching conditions for making the difference in the orientation states in the length direction and the width direction small vary depending on the thermoplastic resin used and its combination. In the case where polyester is used in the A layer, for example, it can be cited that the stretching ratio in the width direction is slightly higher than that in the length direction as a preferred example, and more specifically, the difference between the two is 0.8 times or less. This effect is one of the characteristics of the multilayer film of the present invention and is an effect that cannot be achieved by a polarized light reflection film.

[0121] In the multilayer film of the present invention, it is preferable that in the layers with a layer thickness of 1000 nm or less in the multilayer film, the ratio of the total layer thickness (DA) of the A layer to the total thickness (DB) of the B layer: T (T = DA / DB) satisfies 0.80 ≤ T ≤ 1.00, and the ratio of the total thickness (DC) of the C layer to the total thickness of the B layer: S (S = DC / DB) satisfies 1.10 ≤ S ≤ 1.30. By taking the above values for T and S of the multilayer film of the present invention, the average visible light reflectance of the P wave when incident at an angle of 60° with respect to the normal of the film surface can be effectively increased while maintaining a high transmittance of visible light incident perpendicular to the film surface. In addition, by having a high average visible light reflectance of the P wave when incident at an angle of 60° with respect to the normal of the film surface, it is easy to satisfy Rp20 ≤ Rp40 < Rp60. In the case of the multilayer film of the present invention where the dielectric constant X (that is, related to the refractive index) is in the order of magnitude of X A >X B >X C In the case of such a structure, by taking a larger value for S than for T, the cancellation effect of reflection from 1 / 2 wavelength to 1 / 4 wavelength in the tilt direction is weakened. That is, the average visible light reflectance of the P wave when incident at an angle of 60° with respect to the normal of the film surface can be effectively increased.

[0122] On the other hand, if S is made too large to make it larger than T, and T is made too small, the cancellation effect of reflections of 1 / 2 to 1 / 4 wavelength is weakened not only in the tilted direction but also in the frontal direction (perpendicular to the film surface). Therefore, the transmittance of visible light incident perpendicular to the film surface sometimes becomes lower, and the chroma of transmitted light incident perpendicular to the film surface sometimes becomes higher. Therefore, the lower limit of T is preferably 0.80, and the upper limit of S is preferably 1.30. Conversely, if S is smaller than T, the cancellation effect of reflections of 1 / 2 to 1 / 4 wavelength in the tilted direction is enhanced, and the average reflectance of P-wave visible light incident at an angle of 60° relative to the normal to the film surface sometimes becomes smaller. Therefore, the upper limit of T is preferably 1.00, and the lower limit of S is preferably 1.10. When S exceeds 1.10, the condition Rp20 ≤ Rp40 is sometimes not met. <Rp60。

[0123] The following is a specific example illustrating the fabrication of the multilayer film of the present invention, but the multilayer film of the present invention is not limited thereto. When the multilayer film of the present invention is composed of the aforementioned multilayer film, it can be fabricated by the following method.

[0124] Three extruders—extruder A (corresponding to layer A), extruder B (corresponding to layer B), and extruder C (corresponding to layer C)—supply molten thermoplastic resins (layer 1, layer 2, and layer 3) in a molten state. The molten thermoplastic resins from each flow path are stacked into multiple repeating unit structures using a manifold-type feed block and a square mixer, or simply a comb-type feed block, as is known in stacking devices. These repeating unit structures consist of the three resin layers (layer A, layer B, and layer C) arranged in the order A / B / C / B. Next, the molten stack is melt-extruded into a sheet using a T-die or similar method, and then cooled and solidified on a casting drum to obtain an unstretched multilayer film. It should be noted that each resin can be dried in hot air, vacuum, or a nitrogen atmosphere before being supplied to the extruders, as needed.

[0125] In particular, to efficiently obtain multilayer stacked structures, a feed block with fine slits is preferred. Using such a feed block prevents the apparatus from becoming extremely large, thus reducing the amount of foreign matter generated due to thermal degradation, and enabling high-precision stacking even with an extremely high number of layers. Furthermore, the stacking accuracy in the width direction is significantly improved compared to existing technologies. Additionally, with this apparatus, the thickness of each layer can be adjusted by the shape (length, width) of the slits, thus enabling arbitrary layer thicknesses. The molten multilayer stacked sheet, formed in this way with the desired layer composition, is introduced into a mold and cooled and solidified on a casting drum to obtain an unstretched multilayer stacked film.

[0126] Next, the unstretched multilayer film is stretched and heat-treated. As a stretching method, the known successive biaxial stretching method or simultaneous biaxial stretching method is preferred. The stretching temperature is preferably set to a range above the glass transition temperature of the unstretched multilayer film and below the glass transition temperature +80°C. The glass transition temperature can be measured based on JIS-K-7122 (2012). It should be noted that if there are multiple glass transition temperatures for the unstretched multilayer film, it is preferably set to a range above the highest glass transition temperature and below the glass transition temperature +80°C. The stretching ratio is preferably in the range of 2.0 to 8.0 times in both the length and width directions, more preferably in the range of 3.0 to 6.0 times, and preferably the difference between the stretching ratios in the length and width directions is small, more specifically, 0.8 times or less. Length stretching is preferably performed using the difference in circumferential speed between the rolls of a longitudinal stretching machine. Furthermore, subsequent width stretching is preferably performed using a known stretching method. That is, while holding the two ends of the uniaxially stretched multilayer film in the width direction with clamps, it is transported. By increasing the spacing between the opposing clamps in the width direction, it can be stretched in the width direction.

[0127] Alternatively, simultaneous biaxial stretching is preferably performed using a tenter frame. The simultaneous biaxial stretching process will be explained below. The unstretched laminated film cast on the cooling rollers is fed into the simultaneous biaxial tenter frame, and while being held at both ends in the width direction by clamps, it is conveyed, and simultaneous and / or staged stretching is performed in the length and width directions. Length stretching is achieved by increasing the distance between the clamps on the same side, and width stretching is achieved by increasing the spacing between the opposing clamps, thereby increasing the spacing between the clamps' running tracks. The tenter frame clamps for the stretching / heat treatment in this invention are preferably driven by a linear motor. Other methods include scaling and screw-driven methods, but the linear motor method is superior because it allows for free adjustment of the stretching ratio due to the high degree of freedom of each clamp.

[0128] Further heat treatment after stretching is also preferred. The heat treatment temperature is preferably within a range above the stretching temperature and below the melting point of the thermoplastic resin in layer A, and a cooling process below the heat treatment temperature of -30°C after heat treatment is also preferred. The melting point is determined according to JIS-K-7122 (2012). Furthermore, to minimize the thermal shrinkage of the film, it is also preferable to shrink (relax) the film along its width and / or length direction during the heat treatment or cooling process. The relaxation ratio is preferably in the range of 1% to 10%, more preferably in the range of 1% to 5%. Finally, the multilayer laminated film of the present invention is manufactured by winding the film using a winding machine.

[0129] In the projection image display component of the present invention, the multilayer laminated film of the present invention is located on at least one side of the transparent support or between the transparent components. Specific examples of the projection image display component of the present invention will be described below. Figure 8 (a) and (b) show the configuration in which an arbitrary antireflective layer 31 is stacked on the multilayer laminated film of the present invention. Figure 8 (c) A configuration in which an arbitrary antireflective layer 31 and a functional layer 32 are laminated on the multilayer laminated film of the present invention. The antireflective layer 31 is a layer that prevents surface reflection of the projected image display component, and is preferably located on at least one surface of the multilayer laminated film 4. Figure 8 As shown in (a), by having an anti-reflective layer 31 on at least one surface of the multilayer laminated film 4, oblique reflection of S-waves at the surface of the projection image display member can be suppressed. As a result, when the projection image display member of the present invention is used as a projection member of an augmented reality device, the projection of surrounding scenery other than the image can be suppressed.

[0130] In addition, projection image display components such as Figure 8 As shown in (c), it is also preferable to have a functional layer 32 on at least one surface of the multilayer laminated film 4. Examples of functional layers 32 include hard coatings, wear-resistant layers, scratch-resistant layers, anti-reflective layers, color-correcting layers, ultraviolet absorption layers, light-stabilizing layers, heat-absorbing layers, printing layers, gas barrier layers, adhesive layers, etc. These layers can be single-layer or multi-layer, and one layer can have multiple functions.

[0131] As an example of other solutions, a multilayered film 4 located between transparent supports 18 can be described. Figure 9(a)~(c)). The stacking of the anti-reflective layer 31 and the functional layer 32 here is arbitrary. The transparent support 18 can be glass, a transparent resin substrate, etc., and its thickness is preferably 0.3 mm or more, more preferably 1 mm or more, to provide support. There is no particular upper limit to the thickness of the transparent support 18, but if the thickness is too thick, the weight of the projected image display component will unnecessarily increase; therefore, 10 mm or less is preferred. Furthermore, the transparent support 18 can be either flat or curved. The glass used as the transparent support 18 can be not only single-layer glass, but also laminated glass, tempered glass, flat glass, tempered glass, multi-layer glass, vacuum glass, etc., used in automotive windshields, side windows, rear windows, etc. The transparent resin substrate used as the transparent support 18 is preferably polyethylene terephthalate, polycarbonate, acrylic resins, polyvinyl chloride, polyethylene, polypropylene, polymethylpentene and its copolymers, acrylonitrile / butadiene / styrene copolymers, etc. These transparent resin substrates can be a single component or a mixture of multiple substances. From the viewpoints of transparency, durability, and support, it is more preferable that the transparent support in the projection image display component of the present invention comprises at least one of glass, polycarbonate resin, and acrylic resin. For the same reason, it is also preferable that the thickness of the projection image display component is 0.5 mm or more and 7 mm or less.

[0132] As a method for stacking transparent support 18 and multilayer laminated film 4, it can be as follows: Figure 8 of (a), Figure 9 It can be directly attached as in (a), but it can also be like... Figure 8 (b), (c) Figure 9 As shown in (b) and (c), the adhesive layer 19 is formed by using adhesives, binders, etc., to bond the materials. Examples of adhesives and binders include, for example, 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, cellulose resins, polyvinyl chloride, polyacrylates, polyisobutylene, etc. Furthermore, these adhesives and binders can be used alone or in combination. Additionally, adhesive modifiers, plasticizers, heat stabilizers, antioxidants, UV absorbers, antistatic agents, lubricants, colorants, crosslinking agents, etc., can be added.

[0133] Examples of the pre-processed forms of these adhesives include liquid, gel, block, powder, and film. Examples of curing methods for the adhesive layer include solvent evaporation, moisture curing, heat curing, curing agent mixing, oxygen-free curing, ultraviolet curing, hot melt cooling, and pressure-sensitive methods. Examples of lamination methods include lamination molding, injection molding, vacuum molding, compressed air molding, and vacuum / compressed air molding. By heating, pressurizing, and using the above-mentioned curing methods for the adhesive layer, projection image display components can be manufactured.

[0134] Next, a projection image display device using the multilayer laminated film of the present invention will be described. The projection image display device of the present invention is a projection image display device comprising the multilayer laminated film of the present invention or the projection image display member of the present invention, and an image projection device (light source) for illuminating light onto its display surface.

[0135] Examples of applications of projection image display devices that utilize the multilayer laminated film or projection image display component of the present invention include: Figure 10 The projection image display device shown. Figure 10 The projection image display device of the present invention, as shown, projects a projected image 38 from an image projection device 37 onto a projection image display member 33, thereby projecting the image onto the projection image display member 33. Furthermore, by allowing a background 34, which serves as information about the surrounding scenery, to pass through the projection image display member 33, the user's eye 35 can superimpose the image with the surrounding scenery for visual perception. Examples of image projection devices 37 include liquid crystal projectors, RGB lasers, DLP (Digital Light Processing), LCOS (Liquid Crystal on Silicon), liquid crystal displays, and organic EL displays.

[0136] From the viewpoint of reducing ghosting and minimizing the decrease in visibility when wearing polarized sunglasses, the intensity of P-waves (P-wave intensity / (P-wave intensity + S-wave intensity)) in the light intensity incident on the display surface of the projection image display member of the present invention is preferably 51% or more. It should be noted that the intensity of P-waves in the light intensity incident on the display surface of the projection image display member is sometimes simply referred to as "P-wave intensity". Hereinafter, the problems of ghosting and decreased visibility when wearing polarized sunglasses, which are issues concerning projection image display devices, will be explained with reference to the accompanying drawings. Figure 11As shown in (a), a conventional projection image display member 39 using glass and a transparent resin film reflects S-waves incident from an oblique direction and transmits P-waves. Therefore, the light used to project the image onto the display surface of the projection image display member is S-wave. Ghosting occurs when light is reflected from the front and back surfaces of the image display member 39, and due to this light deflection, the displayed image appears double.

[0137] Furthermore, the reduced visibility when wearing polarized sunglasses is due to the fact that the projected image illuminating the projection image display component originates from S-waves. Therefore, when viewing the projected image through polarized sunglasses that absorb S-waves, the light from the projected image is absorbed by the polarized sunglasses, resulting in [the phenomenon described in the invention]. The projection image display component 33 of the present invention ([…]) Figure 11 (b) Since the P-wave incident from the oblique direction is reflected, the light that forms the projected image incident on the display surface of the projection image display member can use the P-wave. The P-wave is reflected only inside the film and not on the front and back surfaces of the projection image display member, thus mitigating the problem of ghosting. Furthermore, since the P-wave passes through polarized sunglasses, the reduction in the visibility of the projected image caused by polarized sunglasses is also mitigated. From the above viewpoint, the intensity of the P-wave is preferably 51% or more, more preferably 90% or more, and from the viewpoint of polarization control accuracy, the upper limit is approximately 99.9%. In the projection image display device of the present invention, when the intensity of the P-wave is 51% or more, the incident angle of the projected image from the light source is preferably ( Figure 10 Symbol 36) has an angle of 30° or more relative to the normal of the projection image display member, more preferably in the range of 50° to 75°. Here, even if a portion of the projection image display member has a curved shape, the angle of incidence is the angle relative to the tangent plane at the point of incidence of the projected image of the projection image display member. Methods for increasing the intensity of the P-wave include: designing the light source in such a way that the image emitted from the light source becomes a P-wave; and providing a phase retardation plate and a polarizing plate in the light path between the light source and the projection image display member for the image emitted from the light source to the projection image display member.

[0138] The multilayer laminated film or projection image display component of the present invention can be used as a phase retardation plate. Examples of phase retardation plates include a 1 / 2 phase retardation plate and a 1 / 4 phase retardation plate. A 1 / 2 phase retardation plate can change the orientation of linearly polarized light. Therefore, when the image is linearly polarized light, by using a 1 / 2 phase retardation plate, it is possible to control the orientation of the linearly polarized light of the image after passing through the 1 / 2 phase retardation plate to be P-wave relative to the projection image display component. A 1 / 4 phase retardation plate can change circularly polarized light into linearly polarized light. Therefore, when the image is circularly polarized light or elliptically polarized light, by using a 1 / 4 phase retardation plate, it is possible to control the orientation of the linearly polarized light of the image after passing through the 1 / 4 phase retardation plate to be P-wave relative to the projection image display component. A polarizing plate can allow only linearly polarized light of a specific orientation to pass through, absorbing or reflecting linearly polarized light of other orientations. Therefore, by using a polarizing plate, it is possible to control the orientation of the linearly polarized light after passing through the polarizing plate to be P-wave relative to the projection image display component.

[0139] Other applications of the projection image display device that uses the multilayer laminated film or projection image display component of the present invention include head-mounted devices, and more specifically, eyeglass-type devices. Figure 12 This invention illustrates one embodiment of the projection image display device. Figure 12 In the projection image display device, the projected image 38, emitted from the image projection device 37, passes through the light guide member 40 and is reflected by the reflective member 41, and further reflected by the projection image display member 33, thereby projecting the image onto the eyes 35 of the user of the projection image display device while ensuring the visibility of the background 34. Examples of reflective members 41 include mirrors with a metal layer or dielectric multilayer film disposed on the surface of a support, and multilayer films obtained by alternating layers of thermoplastic resins with different refractive indices. As for the light guide member 40, materials such as polyethylene terephthalate, polycarbonate, acrylic, polyvinyl chloride, polyethylene, polypropylene, cycloolefins, polymethylpentene and its copolymers, and acrylonitrile / butadiene / styrene copolymers are preferred, as they have low absorption and transparency of the projected image and a small phase difference to avoid disturbing the polarized light of the projected image.

[0140] The following describes the vehicle according to the present invention. The vehicle of the present invention includes a projection image display device, wherein at least a portion of the light emitted from a light source toward the projection image display member is incident on the projection image display member at an angle of 50° to 75° relative to the normal of the projection image display member. Automobiles, railway vehicles, and aircraft are preferred examples of vehicles. Automobiles are particularly preferred, having a projection image display device, which is the projection image display member of the present invention, in one or more of the front windshield, side windows, and rear window. With this arrangement, ghosting can be suppressed, improving image visibility for the driver. Here, even if a portion of the projection image display member has a curved shape, the angle of incidence is the angle relative to the tangent plane at the point of incidence of the projected image of the projection image display member.

[0141] Furthermore, the vehicle of the present invention preferably includes a projection image display device having a horizontal radius of curvature of 1m or more and 8m or less at the center of the projection image display member. Here, the center of the projection image display member refers to the center of gravity. Because the projection image display member has curvature in the horizontal direction, the distance from the passenger of the vehicle to the projection image display member is nearly equidistant compared to a flat projection image display member. Therefore, the focal distance of each projected image is perceived at an equidistant distance, allowing the images to be viewed without any sense of incongruity.

[0142] The building of the present invention will now be described. The building of the present invention is equipped with the projection image display device of the present invention. Preferably, the projection image display device of the present invention is used for building windows, transparent signage within buildings, spatial performances, etc.

[0143] Example

[0144] The multilayer laminated film and projection image display component of the present invention will be described in more detail below using embodiments. However, the multilayer laminated film and projection image display component of the present invention are not limited to the following embodiments.

[0145] [Methods for determining physical properties and methods for evaluating their effects]

[0146] The methods for determining the properties and evaluating the effects are shown below.

[0147] (1) The number of layers, the number of repeating unit structures, the thickness of the surface layer, and the thickness of the internal layers of the multilayer laminated film.

[0148] Samples with cross-sections cut parallel to the thickness direction (perpendicular to the film surface) using a slicer were observed using a transmission electron microscope (TEM) to confirm the number of layers, the number of repeating unit structures, the thickness of the surface layer, and the thickness of the internal layers of the multilayer film. It should be noted that the cross-sectional photographs were taken after the samples were stained with RuO4 and using a JEM1400Plus TEM (manufactured by Nippon Electron Ltd.) at an accelerating voltage of 100kV. Regarding the thickness of the surface layer of the multilayer film, the obtained TEM images were measured using Image-Prover.10 image processing software. Regarding the thickness of the internal layers of the multilayer film, the obtained TEM images were analyzed using Image-Prover.10 image processing software. In the vertical thickness profile mode, the relationship between the average brightness of the region sandwiched between two lines in the thickness direction and the width direction was read as numerical data. This data was then processed using a 5-point moving average of the position (nm) and brightness data using Excel (registered trademark) (Microsoft Office 365 version 2022). Furthermore, the obtained data on periodic brightness variations is differentiated, and the maximum and minimum values ​​of the differential curve are read using a VBA (Visual Basic Applications) program. The interval between adjacent values ​​is taken as the layer thickness of one layer to calculate the layer thickness. This operation is performed on each image to calculate the layer thickness for all layers, thereby determining the layer thickness within the multilayer film.

[0149] (2) The proportion of units with a total layer thickness of 250 nm or more and 630 nm or less within the repeating unit.

[0150] Using the layer thickness inside the multilayer film obtained in item (1), the total layer thickness in each repeating unit is calculated. The number of repeating units with a total layer thickness of 250 nm or more and 630 nm or less in each repeating unit is divided by the total number of units to obtain the percentage (%).

[0151] (3) Stack ratio (A / B) and stack ratio (C / B) within repeating units

[0152] Using the layer thicknesses within the multilayer film obtained in section (1), the stacking ratio (A / B) is calculated by dividing the thickness of layer A by the total thickness of layers B within each repeating unit, and the stacking ratio (C / B) is calculated by dividing the thickness of layer C by the total thickness of layers B within each unit. For the obtained stacking ratios (A / B) and (C / B), the proportion (%) of repeating units with a stacking ratio of 0.8 or higher and 1.3 or lower is calculated by dividing the total number of units. Similarly, for the stacking ratio (A / B), the proportion (%) of units with a stacking ratio of 0.8 or higher and 1.1 or lower is calculated, and for the stacking ratio (C / B), the proportion (%) of units with a stacking ratio of 0.9 or higher and 1.2 or lower is calculated.

[0153] (4) The ratio of the total layer thickness (T, S) among layers with a thickness of less than 1000 nm.

[0154] Using the layer thickness inside the multilayer film obtained in (1), calculate the ratio of the total layer thickness (DA) of layer A to the total layer thickness (DB) of layer B in layers with a layer thickness of less than 1000nm: T (T=DA / DB), and the ratio of the total layer thickness (DC) of layer C to the total layer thickness of layer B: S (S=DC / DB).

[0155] (5) Determination of dielectric constant X of layers A, B, and C, and the repeating unit structure

[0156] Electron energy loss spectroscopy (EELS) was performed to determine the dielectric constant X of each of layers A, B, and C. A cross-section (thickness direction section) of the sample was prepared using an ultrathin sectioning method along the principal orientation axis of the sample. The dielectric constant of the prepared cross-section sample was determined using an atomic resolution analytical electron microscope (ARM200F) manufactured by NEC. Specifically, HAADF-STEM (High Angle Annular Dark-Field Scanning Transmission Electron Microscopy) images were obtained with an accelerating voltage of 80 kV and a beam spot size of 0.2 mmφ. Then, multi-point analysis (60 × 60 pixels, 20 nm / pixel) was performed on each layer of the sample at 50 msec to obtain data on energy loss and electron beam intensity. The same operation was performed at three points on each of the same thermoplastic resin layers within the multilayer film to obtain data that improved the S / N ratio. From the obtained spectrum, background correction due to elastic scattering and removal of multiple scattering effects are performed. Then, the dielectric function of each layer is calculated using the Kramers-Kronig transformation shown in Equation (C). The integration range for the Kramers-Kronig transformation is set to 0~200 eV. Based on the dielectric function in Equation (C), the real and imaginary parts of the dielectric constant are calculated using Equations (D) and (E), respectively. Then, the dielectric constant X is calculated using Equation (F), which is the square root of the sum of their squares. The order of the dielectric constant X of layers A, B, and C is determined by the calculated dielectric constant X. It should be noted that in Equations (C)~(F), Re represents the real part, Im represents the imaginary part, P represents the Cauchy principal value, ε represents the dielectric constant (average value), ε(ω) represents the dielectric function, ε1 represents the real part of the dielectric constant, ε2 represents the imaginary part of the dielectric constant, and ω and ω' represent angular frequencies.

[0157]

[0158]

[0159]

[0160]

[0161] The determination of the repeating unit structure is achieved by comparing the dielectric constant X of layer A, layer B, and layer C at the location of the measured layer with the contrast of the TEM image measured in item (1) at the location of the layer, thereby identifying the layers with three contrasts in the TEM image as layer A, layer B, and layer C respectively, and confirming that the layers A, B, and C are stacked in a unit structure of layer A / layer B / layer C / layer B.

[0162] (6) Transmittance

[0163] Using a standard configuration (solid-state measurement system) of a Hitachi U-4100 spectrophotometer manufactured by Hitachi, Ltd., the transmittance at various incident angles θ=0° and 10° at wavelengths of 240–2600 nm was measured at 1 nm intervals. (Measurement conditions: slit width 2 nm (visible) / automatic control (infrared), gain 2, scan speed 600 nm / min). The average transmittance at an incident angle of 0° for wavelengths of 400 nm–700 nm, representing the transmittance of visible light incident perpendicular to the film surface, was calculated from the measured results.

[0164] (7) Average visible light reflectance of P-wave when incident at an angle of 60° relative to the normal of the film surface.

[0165] A variable-angle reflectance unit and a Glan-Taylor polarizer were installed on a Hitachi U-4100 spectrophotometer to measure the reflectance of P-waves in the wavelength range of 380–780 nm at an incident angle θ = 60°. The average reflectance of P-waves in the wavelength range of 400–700 nm was calculated from the obtained reflectance. The 60° tilt direction was set along the principal orientation axis of the multilayer film.

[0166] (8) Average reflectivity of P-wave, Rp20, Rp40, Rp60

[0167] A variable-angle reflectance unit and a Glan-Taylor polarizer were installed on a Hitachi U-4100 spectrophotometer to measure the reflectance of P-waves in the wavelength range of 400–700 nm at incident angles θ = 20°, 40°, and 60° at 1 nm intervals. The average reflectances of P-waves in the wavelength range of 400–700 nm at incident angles of 20°, 40°, and 60°, Rp20, Rp40, and Rp60, were calculated from the obtained reflectances. The tilt directions at 20°, 40°, and 60° were set along the principal orientation axis of the multilayer film.

[0168] (9) Azimuth deviation of the average reflectivity of P-waves

[0169] A variable-angle reflectance unit and a GranTaylor polarizer were installed on a Hitachi U-4100 spectrophotometer. Using the azimuth angle of 0° along the sample's principal orientation axis as a reference, the reflectance of P-waves in the wavelength range of 400–700 nm was measured at 1 nm intervals along the azimuth direction of each of these five points, rotating 0°, 45°, 90°, 135°, and 180° to the right. The average reflectance of P-waves in the wavelength range of 400–700 nm at an incident angle of 60° was then calculated from the obtained reflectance values ​​as Rp60(0°), Rp60(45°), Rp60(90°), Rp60(135°), and Rp60(180°) at the incident angle of 60° for each azimuth direction. Furthermore, the difference between the maximum and minimum values ​​of Rp60(0°), Rp60(45°), Rp60(90°), Rp60(135°), and Rp60(180°) is set as the azimuth deviation.

[0170] (10) The chroma of the reflected light from a P-wave incident at 60°

[0171] Based on JIS-Z-8781-3 (2016), the tristimulus values ​​X, Y, Z of the CIE 1931 color system and the tristimulus values ​​Xn, Yn, Zn of a specific white light are calculated. Using the obtained X, Y, Z and Xn, Yn, Zn, the a* and b* values ​​of the CIE 1976 L*a*b* color space are then used as the chroma C based on JIS-Z-8781-4 (2013). * Value, in a * and b * Calculate the square root of the sum of the squares of the two sides.

[0172] <Calculation of the three stimulus values ​​X, Y, Z, and the three stimulus values ​​Xn, Yn, Zn of a specific white light>

[0173] In JIS-Z-8781-3 (2016), the relative color stimulus function (φ(λ)) is defined as the product of the spectral reflectance coefficient (R(λ)) and the relative spectral distribution of the illumination light (S(λ)) φ(λ) = R(λ) × S(λ). Here, the spectral reflectance coefficient is the reflectance of the P-wave at an incident angle of 60° with wavelengths of 380 nm to 780 nm, as calculated in item (6). The relative spectral distribution uses the auxiliary illuminator C of JIS-Z-8720 (2012). Using the relative color stimulus function, based on equation (G) of JIS-Z-8781-3 (2016), the sum of the products of the relative color stimulus function and the color functions (H) of CIE1931 (described below) at wavelengths of 380 nm to 760 nm, at wavelength intervals of 5 nm, is multiplied by the normalization factor k to calculate the tristimulus values ​​X, Y, and Z. The specific tristimulus values ​​Xn, Yn, and Zn of white light are calculated by multiplying the sum of the products of the relative spectral distribution and each of the CIE 1931 isochromatic functions (H) by a normalization factor k. It should be noted that in equation (G), λ represents the wavelength, and Δλ represents the wavelength interval.

[0174]

[0175]

[0176] (11) The chroma of transmitted light incident perpendicular to the film surface

[0177] Based on JIS-Z-8781-3 (2016), the tristimulus values ​​X, Y, Z of the CIE1931 color system and the tristimulus values ​​Xn, Yn, Zn of a specific white light are calculated. Using the obtained X, Y, Z and Xn, Yn, Zn, based on JIS-Z-8781-4 (2013), the a* and b* values ​​of the CIE1976 L*a*b* color space are determined, and these are used as the chroma C. * Value, in a * and b * Calculate the square root of the sum of the squares of the two sides.

[0178] <Calculation of the three stimulus values ​​X, Y, Z, and the three stimulus values ​​Xn, Yn, Zn of a specific white light>

[0179] In JIS-Z-8781-3 (2016), the relative color stimulus function (φ(λ)) is set as the product of the spectral transmittance coefficient (T(λ)) and the relative spectral distribution of the illumination light (S(λ)) φ(λ) = T(λ) × S(λ). Here, the spectral transmittance coefficient is the transmittance for wavelengths of 380 nm to 780 nm obtained in (6). The relative spectral distribution uses the auxiliary illuminator C of JIS-Z-8720 (2012). Using the relative color stimulus function, based on equation (G) of JIS-Z-8781-3 (2016), the three stimulus values ​​X, Y, and Z are calculated by multiplying the sum of the products of the relative color stimulus function and the color functions (G) of CIE1931 (described below) at wavelength intervals of 5 nm from 380 nm to 760 nm by the normalization factor k. The three stimulus values ​​Xn, Yn, and Zn of a specific white light are calculated by multiplying the sum of the products of the relative spectral distribution and each of the CIE 1931 isochromatic functions (G) by a normalization factor k.

[0180] (12) Near-infrared reflectance

[0181] Using a standard configuration (solid-state measurement system) of a Hitachi U-4100 spectrophotometer, the reflectance at an incident angle θ = 10° was measured at 1 nm intervals in the wavelength range of 240–2600 nm. (Measurement conditions: slit width 2 nm (visible) / automatic control (infrared), gain 2, scan speed 600 nm / min). The wavelength range with a reflectance of 40% or higher in the near-infrared range and the average reflectance within that range were then determined from the obtained reflectance data.

[0182] (13) Refractive index and planar orientation coefficient of layer A

[0183] use The company manufactures a SPA-400 prism coupler to measure the refractive index of the surface layer of a multilayer film using a laser wavelength of 633nm. The in-plane refractive index (average of the X and Y directions) and the direct refractive index (average of the X and Z directions) are determined for the principal orientation axis (X direction) and the direction perpendicular to the principal orientation axis (Y direction is defined as parallel to the film surface, and Z direction as perpendicular to the film surface). The difference between the in-plane refractive index and the direct refractive index is calculated and set as the plane orientation coefficient.

[0184] (14) The ratio of the dielectric constant of layer B in the in-plane direction to that in the direction perpendicular to the plane.

[0185] The dielectric constant of layer B in the direction perpendicular to the plane is set as the dielectric constant of layer B obtained in item (5). The dielectric constant of layer B in the in-plane direction is obtained by the following method. First, the dielectric constant is obtained by electron energy loss spectroscopy (EELS measurement) in item (5) for the normal direction of the surface of the multilayer film, and it is set as the dielectric constant of layer A in the in-plane direction. Regarding the resin used in layer C, thermoplastic resin particles that have been vacuum dried at 70°C for 48 hours are melted at 280°C, pressurized and rapidly cooled to produce a sheet with a thickness of 200 μm. The dielectric constant is obtained by electron energy loss spectroscopy (EELS measurement) in item (5) for the normal direction of the surface of the sheet, and it is set as the dielectric constant of layer C in the in-plane direction. Next, the surface of the multilayer film is ground, and the dielectric constant is obtained by electron energy loss spectroscopy (EELS measurement) in item (5) for the normal direction of the ground surface. If the dielectric constant differs from the in-plane dielectric constants of layers A and C, this dielectric constant is set as the in-plane dielectric constant of layer B. Here, "different from the in-plane dielectric constants of layers A and C" means a difference of 3% or more in the dielectric constant. The dielectric constant measured using the above method is obtained by continuously grinding and measuring the dielectric constant until a value different from the in-plane dielectric constants of layers A and C appears. The value at which this difference appears is set as the in-plane dielectric constant of layer B. Based on the obtained in-plane and perpendicular-plane dielectric constants of layer B, the ratio ((in-plane direction - perpendicular-plane direction) / perpendicular-plane direction × 100) is calculated.

[0186] (15) Determination of the crystallinity / amorphity of layers A, B, and C

[0187] 5mg of resin particles used in layers A, B, and C were measured using an electronic balance and clamped in an aluminum pan. (Company Name) A DSCvesta Smart Loader was prepared and measured according to JIS-K-7122 (2012), with the temperature increased from 25°C to 300°C at a rate of 20°C / min. The enthalpy of fusion (ΔHm) was calculated from the obtained DSC data. Layers of resin with an enthalpy of fusion greater than 5 J / g were considered crystalline, while layers of resin with an enthalpy of fusion less than 5 J / g were considered amorphous.

[0188] (16) Refractive index of the C layer

[0189] Thermoplastic resin granules, vacuum dried at 70℃ for 48 hours, were melted at 280℃, then pressurized and rapidly cooled to produce sheets with a thickness of 200μm. The company uses a SPA-400 prism coupler to determine the refractive index of the obtained sheet using the same method as in (13). Since the resin used in layer C is amorphous, the refractive index of the sheet is considered to be the same as that in the multilayer laminated film.

[0190] (17) Refractive index of layer B

[0191] Since layer B is an inner layer of a multilayer laminated film, the use of layer B resin alone, produced under the same stretching / heat treatment conditions as the multilayer laminated film, is not for the multilayer laminated film itself. The company uses a SPA-400 prism coupler to measure the refractive index. The laser wavelength used for measurement is 633nm. The in-plane refractive index is set as the average of the values ​​obtained from both sides of the film in the direction of the principal orientation axis and the direction perpendicular to the principal orientation axis. The out-of-plane refractive index is set as the average of the values ​​obtained from both sides of the film, specifically the average of the values ​​measured from the side along the principal orientation axis and the average of the values ​​measured from the side perpendicular to the principal orientation axis.

[0192] (18) Verification of the refractive index of the B layer of a multilayer film

[0193] Optical simulations of reflectance were performed using the layer thickness of the multilayer film calculated in item (1), the refractive index of layer A of the multilayer film calculated in item (13), the refractive index of layer C calculated in item (16), and the refractive index of layer B calculated in item (17). The results of these optical simulations were compared with the near-infrared reflectance measured in item (12). If the difference between the two was less than ±3%, the refractive index of layer B calculated in item (17) was considered the refractive index of layer B of the multilayer film. The optical simulation was performed using the characteristic matrix method of optical thin films (…). (2006). Optical Thin Film Filter Design Co., Ltd. The company uses VBA programs for calculations.

[0194] (19) Main orientation axis direction

[0195] Orientation degree was measured using a molecular orientation meter MOA-7015 manufactured by Oji Corporation, and the direction with the highest orientation degree was set as the main orientation axis direction.

[0196] (20) Evaluation of projection image display devices

[0197] Light source usage The company-manufactured display (SP-133CM) features a projection image display component positioned at a 45° angle to the light source. Light emitted perpendicularly from the light source strikes the surface of the projection image display component at a 45° angle relative to the normal direction. By controlling the transmission axis direction of a polarizing plate positioned directly above the light source, the intensity of the P-wave in the image incident on the display surface of the projection image display component is adjusted (P-wave intensity / (P-wave intensity + S-wave intensity)). The image emitted from the light source uses a white grid pattern. Figure 13 A schematic diagram of the evaluation structure is displayed. The image projected onto the projection image display component is used for visual evaluation of each item according to the following criteria. Figure 13 The detailed structure of the projected image display component 33 is not illustrated in the figures, but the projected image display components in each embodiment and comparative example have the structures shown in Table 3. It should be noted that... Figure 13 In the text, symbols 33-35, 37, and 38 respectively represent the following contents: 33: projection image display component, 34: background, 35: the user's eyes of the projection image display device, 37: image projection device, and 38: projection image.

[0198] (Displayability of a projected image at an incident angle of 60°)

[0199] The following criteria will be used for evaluation, and A and B will be set as qualified.

[0200] A: The projected image is very bright.

[0201] B: The projected image is bright.

[0202] C: The projected image is dark or invisible.

[0203] (Recognition of projection images at an incident angle of 60°)

[0204] Evaluation will be conducted according to the following criteria, with A and B being considered acceptable. Here, "ghosting" refers to the phenomenon where a projected image appears to be split into two or more parts. This includes not only double ghosting but also instances of triple or higher-level ghosting.

[0205] A: No ghosting was observed.

[0206] B: Ghosting to a degree that does not affect the visual recognition of the image.

[0207] C: Ghosting was observed at levels exceeding B.

[0208] D: No projected image was observed, therefore the visual recognition of ghosting cannot be evaluated.

[0209] (Visual recognition of the grid-like image of a projected image)

[0210] The following criteria will be used for evaluation, and A and B will be set as qualified.

[0211] A: Visually recognizes an undistorted grid image.

[0212] B: Visually recognizes a grid image with large distortion.

[0213] C: Visually recognized as a grid image with extremely large distortion.

[0214] D: No projected image was observed, therefore the distortion of the grid image cannot be evaluated.

[0215] (The visual recognition of color in projected images)

[0216] The following criteria will be used for evaluation, with A through C being considered acceptable.

[0217] A: The white color is basically the same as the projected image.

[0218] B: An image in which the color has changed slightly from white is considered to be of a practically acceptable quality.

[0219] C: Visually perceive an image whose color has changed from white.

[0220] D: No projected image was observed, therefore the visual recognition of color cannot be evaluated.

[0221] (Background visibility)

[0222] The following criteria will be used for evaluation, and A and B will be set as qualified.

[0223] A: The background is clearly visible.

[0224] B: See the background to the extent that it is practically problem-free.

[0225] C: The background appears dark, exceeding the level of B.

[0226] D: The background appears dark or is not visible, exceeding level C and causing practical problems.

[0227] (21) Evaluation of thermal insulation performance

[0228] Using the transmittance measured at an incident angle of 10° in section (6) and the reflectance measured at an incident angle of 10° in section (12), the solar radiation heat gain (Tts) is calculated according to ISO 13837:2008(E). Tts refers to the percentage (%) of solar heat energy passing through the film / projection image display component when the solar heat energy incident on the film / projection image display component is set to 100. The lower the value, the higher the heat insulation performance. A value below 80% is considered to have heat insulation performance.

[0229] (22) Glass transition temperature and melting point of resin and unstretched multilayer laminated film

[0230] Measure 5 mg of thermoplastic resin granules or unstretched multilayer film using an electronic balance, clamp them in an aluminum tray, and use (Company Name). A DSCvesta Smart Loader was fabricated and measured according to JIS-K-7122 (2012) at a rate of 20°C / min from 25°C to 300°C. The glass transition temperature (Tg) and melting point (Tm) were determined from the obtained DSC data. The highest glass transition temperatures among unstretched multilayer films are shown in Table 1.

[0231] [Thermoplastic resin used in the membrane]

[0232] The films used in the various embodiments and comparative examples were manufactured using the following resins. It should be noted that all of them are thermoplastic resins; resins A, B, F, G, and M are crystalline, while resins C, D, E, H, I, J, K, and L are amorphous.

[0233] Resin A: A copolymer of polyethylene naphthalate (polyethylene naphthalate copolymerized with polyethylene glycol of molecular weight 400, which has a total content of 6 mol% relative to the glycol content), Tg=93℃, Tm=253℃.

[0234] Resin B: Polyethylene terephthalate, Tg=78℃, Tm=254℃.

[0235] Resin C: A copolymer of polyethylene terephthalate (polyethylene terephthalate copolymerized with 30 mol% of 2,6-naphthalic acid relative to the total acid content), Tg=95℃, Tm not observed.

[0236] Resin D: A copolymer of polyethylene naphthalate (polyethylene naphthalate copolymerized with 35 mol% terephthalic acid relative to the total glycol content and 8 mol% polyethylene glycol with a molecular weight of 400 relative to the total glycol content), Tg=87℃, Tm not observed.

[0237] Resin E: A copolymer of polyethylene naphthalate (polyethylene naphthalate copolymerized with 30 mol% isophthalic acid relative to the acid content and 6 mol% polyethylene glycol of molecular weight 400 relative to the glycol content), Tg=73℃, Tm not observed.

[0238] Resin F: Particles of resin J and resin B, described later, are blended in a ratio of 60% by mass to 40% by mass. Tg = 79℃, Tm = 243℃.

[0239] Resin G: A copolymer of polyethylene terephthalate (polyethylene terephthalate copolymerized with 12 mol% isophthalic acid content relative to the overall acid content), Tg=75℃, Tm=218℃.

[0240] Resin H: Polymethyl methacrylate, Tg=103℃, Tm not observed.

[0241] Resin I: A copolymer of polyethylene terephthalate (copolymerized with 20 mol% cyclohexanedicarboxylic acid and 20 mol% spirocyclodiol relative to the total acid content), Tg=76℃, Tm not observed.

[0242] Resin J: A copolymer of polyethylene terephthalate (polyethylene terephthalate copolymerized with cyclohexanediol content of 33 mol% relative to the total glycol content), Tg=80℃, Tm not observed.

[0243] Resin K: A copolymer of polyethylene naphthalate (polyethylene naphthalate copolymerized with 20 mol% isophthalic acid relative to the acid content and 5 mol% polyethylene glycol with a molecular weight of 400 relative to the glycol content), Tg=85℃, Tm=215℃.

[0244] Resin L: A copolymer of polyethylene terephthalate (copolymerized with 50 mol% 2,6-naphthalic acid relative to the overall acid content of polyethylene terephthalate), Tg=105℃, Tm not observed.

[0245] Resin M: A copolymer of polyethylene terephthalate (polyethylene terephthalate copolymerized with cyclohexanediol content of 18 mol% relative to the total diol content), Tg=78℃, Tm=220℃, ΔHm=13J / g.

[0246] (Multilayer laminated membranes, membrane manufacturing)

[0247] Multilayer membranes and membranes are fabricated as follows, with the membrane fabrication conditions shown in Table 1 and the evaluation results shown in Table 2.

[0248] (Example 1)

[0249] Resin A was used as the thermoplastic resin constituting layer A, Resin C was used as the thermoplastic resin constituting layer B, and Resin H was used as the thermoplastic resin constituting layer C. Resins A, C, and H were melted at 280°C using different extruders. After passing through a 5-piece FSS-type impeller filter, they were metered using a gear pump at a discharge ratio of layer A / layer B = 1.42 and layer C / layer B = 1.05. The layers were stacked using a 601-layer feed block (stacking device) designed as follows (150 repeating units, 151 layers of layer A, 300 layers of layer B, and 150 layers of layer C). The stacking method was such that the layer thickness of layers A, B, and C continuously varied from one surface layer to the opposite surface layer according to formula (A) with a reflected wavelength of 850nm to 1750nm at an incident angle of 10°, and the stacking configuration was (layer A / layer B / layer C / layer B)nA layers (n is an integer representing the number of repeating units). The ratio of the amount of resin extruded using a gear pump is generally referred to as the stacking ratio. However, since the amount of resin extruded also includes the outermost A layer, the amount of A layer, which serves as a protective film, is increased.

[0250] Next, the molten laminate is fed into a T-die to form a sheet, and then rapidly cured on a casting drum with a surface temperature maintained at 25°C while applying an 8kV electrostatic voltage via wire, to obtain an unstretched multilayer laminate film. This unstretched multilayer laminate film is then longitudinally stretched (stretched along its length) at a stretch ratio of 3.6 times at 105°C, and subjected to corona discharge treatment on both sides in air. Then, a film coating solution for forming an easy-to-adhere layer is applied using a #4 rod coating method (a 1:1 mass ratio mixture of polyester resin with a glass transition temperature of 18°C ​​and polyester resin with a glass transition temperature of 82°C, further mixed with 3 parts by mass of silica particles with an average primary particle size of 100nm). The average primary particle size here is a value determined using dynamic light scattering. Then, the obtained uniaxially stretched multilayer film was held at both ends in the width direction by a clamp and fed into a tenter frame. It was then transversely stretched (stretched in the width direction) at a stretch ratio of 4.2 times at 120°C. Further, the transversely stretched multilayer film was heat-treated at 210°C and relaxed by 1% in the width direction, then cooled at 100°C to obtain a multilayer film with a thickness of 71 μm (5 μm for the two surface layers). The evaluation results are shown in Table 2. It should be noted that the film thickness, number of layers, surface layer thickness, and stack ratio were adjusted by changing the traction speed of the casting drum, the number of slits in the feed block, the slit width of the feed block, and the discharge rate, so that the resin content, number of layers, surface layer thickness, overall thickness, stack ratio, and film-forming conditions for each layer are as shown in Table 1. The results are shown in Table 2. It should be noted that the film thickness, number of layers, surface layer thickness, and layer ratio are adjusted by changing the traction speed of the casting drum, the number of slits in the feed block, the width of the slits in the feed block, and the discharge rate, respectively.

[0251] (Examples 2-18 and Comparative Examples 1, 4-8)

[0252] The resin composition, number of layers, surface layer thickness, overall thickness, stack ratio, and film-forming conditions for each layer are shown in Table 1. A feed block of the following design was used, and the process was otherwise identical to that in Example 1 to obtain a multilayer laminated film. The evaluation results are shown in Table 2. The feed block used is shown below.

[0253] The feeding block of Example 2: A 401-layer feeding block (stacked device) designed in the following manner (100 repeating units, 101 layers of layer A, 200 layers of layer B, and 100 layers of layer C), wherein the layer thickness of layer A, layer B, and layer C is continuously varied from one surface layer to the opposite surface layer according to formula (A) with a reflected wavelength of 850nm~1700nm at an incident angle of 10°, and the stacked configuration is (layer A / layer B / layer C / layer B)nA layers (n is an integer representing the number of repeating units).

[0254] The feeding block of Example 3: A 201-layer feeding block (stacked device) designed in the following manner (50 repeating units, 51 layers of layer A, 100 layers of layer B, and 50 layers of layer C), wherein the layer thickness of layer A, layer B, and layer C is continuously varied from one surface layer to the opposite surface layer according to formula (A) with a reflected wavelength of 850nm~1650nm at an incident angle of 10°, and its stacked configuration is (layer A / layer B / layer C / layer B)nA layers (n is an integer representing the number of repeating units).

[0255] Feed blocks for Examples 4, 7, 9, 10, 13-18, and Comparative Examples 1, 6-9: The same feed blocks as in Example 1 were used.

[0256] The feeding blocks of Examples 5 and 6 are 601-layer feeding blocks (stacked devices) designed as follows (150 repeating units, 151 layers of layer A, 300 layers of layer B, and 150 layers of layer C). The method is as follows: the layer thickness of layers A, B, and C changes continuously from one surface layer to the opposite surface layer according to formula (A) with a reflected wavelength of 850nm~1650nm at an incident angle of 10°, and the stacked configuration is (layer A / layer B / layer C / layer B)nA layers (n is an integer representing the number of repeating units).

[0257] The feed block of Example 8: A 601-layer feed block (stacked device) designed in the following manner (150 repeating units, 151 layers of layer A, 300 layers of layer B, and 150 layers of layer C), wherein the layer thickness of layer A, layer B, and layer C is continuously varied from one surface layer to the opposite surface layer according to formula (A) with a reflected wavelength of 850nm~1400nm at an incident angle of 10°, and its stacked configuration is (layer A / layer B / layer C / layer B)nA layers (n is an integer representing the number of repeating units).

[0258] The feed block of Example 11: A 601-layer feed block (stacked device) designed as follows (150 repeating units, 151 layers of layer A, 300 layers of layer B, and 150 layers of layer C), wherein the layer thickness of layers A, B, and C is continuously varied from one surface layer to the opposite surface layer according to formula (A) with a reflected wavelength of 850nm~1750nm at an incident angle of 10°, and its stacked configuration is (layer A / layer B / layer C / layer B)nA layers (n is an integer representing the number of repeating units), wherein the stack ratio (A / B) and stack ratio (C / B) within the unit are the same as in Example 1 from layer 1 to layer 528, and from layer 529 to layer 601, the stack ratio (A / B) and stack ratio (C / B) within the unit are designed to be 0.7. The term "first layer" here refers to the position of the layer when the multilayer film is divided into two parts with equal thickness, and the layer is counted from the surface of the side with more layers.

[0259] Comparative Example 4: A 601-layer feed block (stacked device) designed in the following manner (150 repeating units, 151 layers of layer A, 300 layers of layer B, and 150 layers of layer C), wherein the layer thickness of layers A, B, and C is continuously varied from one surface layer to the opposite surface layer according to formula (A) with a reflected wavelength of 580nm to 1650nm at an incident angle of 10°, and its stacked configuration is (layer A / layer B / layer C / layer B)nA layers (n is an integer representing the number of repeating units).

[0260] Comparative Example 5: A 601-layer feed block (stacked device) designed in the following manner (150 repeating units, 151 layers of layer A, 300 layers of layer B, and 150 layers of layer C), wherein the layer thickness of layers A, B, and C is continuously varied from one surface layer to the opposite surface layer according to formula (A) with a reflected wavelength of 850nm to 2300nm at an incident angle of 10°, and its stacked configuration is (layer A / layer B / layer C / layer B)nA layers (n is an integer).

[0261] The feed block of Example 11: A 601-layer feed block (stacked device) designed in the following manner (150 repeating units, 151 layers of layer A, 300 layers of layer B, and 150 layers of layer C), wherein the layer thickness of layers A, B, and C is continuously varied from one surface layer to the opposite surface layer according to formula (A) with a reflected wavelength of 850nm to 1750nm at an incident angle of 10°, and its stacked configuration is (layer A / layer B / layer C / layer B)nA layers (n is an integer representing the number of repeating units), wherein the stack ratio (A / B) and stack ratio (C / B) within the unit are the same as in Example 1 from layer 1 to layer 505, and from layer 506 to layer 601, the stack ratio (A / B) and stack ratio (C / B) within the unit are designed to be 0.7. The term "first layer" here refers to the position of a layer when the multilayer film is divided into two parts with equal thickness, and the layer is counted from the surface of the side with more layers.

[0262] The feed block of Example 12: A 601-layer feed block (stacked device) designed as follows (150 repeating units, 151 layers of layer A, 300 layers of layer B, and 150 layers of layer C), wherein the layer thickness of layers A, B, and C is continuously varied from one surface layer to the opposite surface layer according to formula (A) with a reflected wavelength of 850nm to 1750nm at an incident angle of 10°, and its stacked configuration is (layer A / layer B / layer C / layer B)nA layers (n is an integer representing the number of repeating units), wherein the stack ratio (A / B) and stack ratio (C / B) within the unit are the same as in Example 1 from layer 1 to layer 421, and from layer 422 to layer 601, the stack ratio (A / B) and stack ratio (C / B) within the unit are designed to be 0.7. The term "first layer" here refers to the position of a layer when the multilayer film is divided into two parts with equal thickness, and the layer is counted from the surface of the side with more layers.

[0263] (Comparative Example 2)

[0264] Resin A is used as the thermoplastic resin constituting layer A, and Resin J is used as the thermoplastic resin constituting layer C. Resin A and Resin J are melted separately using an extruder at 280°C. After passing through a 5-piece FSS-type impeller filter, they are metered using a gear pump at a discharge ratio (layer ratio) of A layer / C layer = 1.2. At the same time, they are stacked using a 401-layer feed block (stacking device) designed as follows (201 layers of A layer and 200 layers of C layer). The stacking method is as follows: the layer thickness of layers A and C layer is continuously varied from one surface layer to the opposite surface layer according to formula (A) with a reflected wavelength of 850nm~1200nm at an incident angle of 10°, and the stacking configuration is (A layer / C layer)nA layer (n is an integer representing the number of repeating units). Next, the molten multilayer was fed into a T-die to form a sheet, and then rapidly cured on a casting drum with a surface temperature maintained at 25°C while applying an 8kV electrostatic voltage via wire, to obtain an unstretched multilayer film. Otherwise, the procedure was the same as in Example 1, yielding a multilayer film with a thickness of 74μm (5μm for both surface layers). The evaluation results are shown in Table 2.

[0265] (Comparative Example 3)

[0266] Using an 801-layer feed block (stack assembly) designed as follows (layer A is 401 layers and layer C is 400 layers), and with the resin, number of layers, surface layer thickness, overall thickness, stack ratio, and film-forming conditions of each layer as shown in Table 1, except that a multilayer laminated film was obtained by operating in the same manner as Comparative Example 2, wherein the layer thickness of layers A and C was continuously varied from one surface layer to the opposite surface layer according to Equation (A) with the reflected wavelength of the P-wave at an incident angle of 60° being 400nm~800nm, and the stack configuration was (layer A / layer C)nA layers (n is an integer representing the number of repeating units). The evaluation results are shown in Table 2.

[0267] (Verification of the refractive index of layer B)

[0268] Regarding Examples 1-18, Comparative Examples 1, and Comparative Examples 4-9, the verification of the refractive index of the B layer of the multilayer film based on item (18) was carried out, and the difference between the optical simulation results and the reflectivity was less than ±3%. Therefore, the refractive index of the B layer calculated in item (17) is regarded as the refractive index of the B layer of the multilayer film.

[0269] [Table 1]

[0270]

[0271] Comparative Examples 2 and 3 have only layers A and C in their multilayer films, so the value of A / C is recorded in column A / B regarding the stacking ratio.

[0272] [Table 2]

[0273]

[0274] (Examples 19-39, Comparative Examples 9-20)

[0275] Examples 19-39 and Comparative Examples 9-20 are examples and comparative examples of projection image display components having multilayer laminated films. Regarding the manufacture of the laminate, laminates of the multilayer laminated film of Comparative Example 2 and the multilayer laminated film of Comparative Example 3 were manufactured. Films of A4 size were laminated using an acrylic optical adhesive sheet with an adhesive layer thickness of 25 μm. The lamination used… A roller laminator (MRK-600) was used. Next, regarding the manufacture of projection image display components 1-18, 21-27, and 29-31, a 2mm thick, A4-sized float glass plate was laminated with A4-sized films and laminates of Examples 1-12 and Comparative Examples 1-6 using an acrylic optical adhesive sheet with an adhesive layer thickness of 25μm. This produced projection image display components with a float glass plate / 25μm thick acrylic adhesive layer / film structure, designated as projection image display components 1-18, 21-27, 29, and 30, respectively. The lamination process used... Roller-type laminator (MRK-600). The projection image display component 18, produced using the laminate, exhibits wrinkles and irregular, uneven deformation with a 3-4 mm cycle. On the other hand, wrinkles and deformations are not observed in projection image display components 1-17, 21-27, 29, and 31.

[0276] (Manufacturing of Projected Image Display Component 19) A laminated glass with the following composition was manufactured using a 2mm thick, A4-sized float glass sheet, a 0.76mm thick PVB (polyvinyl butyral), and the multilayer laminated film of Example 1. Laminated glass composition: float flat glass / PVB / multilayer laminated film of Example 1 / PVB / float flat glass. For the fabrication of the laminated glass, Nisshinbo LAMINATOR0303S was used as the laminating device. The laminated body, overlapping to form the laminated glass composition, was placed in the laminating device, vacuumed at 100°C for 5 minutes, further vacuumed at 130°C for 5 minutes, and then pressed at a pressure of 0.1 MPa for 60 minutes.

[0277] (Manufacturing of projection image display component 28) Instead of the multilayer laminated film of Example 1, the multilayer laminated film of Example 13 was used, and otherwise manufactured using the same method as the projection image display component 19.

[0278] (Manufacturing of Projection Image Display Component 20) A laminated glass with the following configuration was manufactured using the same method as the projection image display component 19. The laminated glass configuration is: float glass / PVB / laminate / PVB / float glass. The projection image display component 19 exhibited slight uneven deformation, but no wrinkles were observed. On the other hand, the projection image display component 20 produced large wrinkles and uneven deformation with a period of 1-2 mm.

[0279] Regarding the projection image display devices of Examples 19-39 and Comparative Examples 9-20, as shown in Table 3, the projection image display devices were evaluated using projection image display components 1-30. The combination of the projection image display components used, the intensity of the P-wave, and the evaluation results of the projection image display devices are shown in Table 3.

[0280] [Table 3]

[0281]

[0282] Industrial availability

[0283] This invention relates to a multilayer laminated film that transmits visible light in the front direction while being transparent, and simultaneously possesses near-infrared reflection capabilities and reflects P-wave visible light in the tilted direction. The multilayer laminated film of this invention is suitable for use in projection image display components, projection image display devices using such components, and vehicles and buildings using such projection image display devices.

[0284] Symbol Explanation

[0285] 1: Multilayer laminated film that reflects near-infrared rays

[0286] 2: Multilayer film reflecting visible P-wave light

[0287] 3: Laminated film

[0288] 4: Multilayer laminated membrane

[0289] 5: One of the two different thermoplastic resin layers in a multilayer laminated film that reflects near-infrared rays.

[0290] 6: The other of the two different thermoplastic resin layers in a multilayer laminated film that reflects near-infrared rays.

[0291] 7: One of the two different thermoplastic resin layers in a multilayer film that reflects visible P-wave light.

[0292] 8: The other of the two different thermoplastic resin layers in a multilayer film that reflects visible P-wave light.

[0293] 9: A layer

[0294] 10: Floor B

[0295] 11: Floor C

[0296] 12: Transparent adhesive

[0297] 13: Visible light incident along the frontal direction

[0298] 14: Near-infrared rays

[0299] 15: P-wave in the tilt direction

[0300] 16: Laminated glass (composed of multiple layers of laminated films between glass panes)

[0301] 17: Laminated glass (composed of multiple layers of laminated films on the surface)

[0302] 18: Transparent support (glass)

[0303] 19: Adhesive layer

[0304] 20: Reflectivity of P-waves

[0305] 21: Reflectivity of S-waves

[0306] 22: Refractive index (Naθ) of layer A at incident angle θ

[0307] 23: Refractive index (Ncθ) of layer C at incident angle θ

[0308] 24: Refractive index (Nbθ) of layer B of the multilayer film (Example 1) at an incident angle θ

[0309] 25: Refractive index (Nbθ) of layer B of a multilayer film reflecting near-infrared light (Comparative Example 1) at an incident angle θ.

[0310] 26: Average visible light reflectance of P-wave of multilayer laminated film (Example 1)

[0311] 27: Average visible light reflectance of P-wave of a multilayer film reflecting near-infrared light (Comparative Example 1)

[0312] 28: Thickness of layer A

[0313] 29: Thickness of layer C

[0314] 30: Thickness of layer B

[0315] 31: Anti-reflective layer

[0316] 32: Functional Layer

[0317] 33: Projected image display component

[0318] 34: Background

[0319] 35: The eyes of the user of the projected image display device

[0320] 36: Angle of incidence of the projected image

[0321] 37: Image projection device

[0322] 38: Projected Image

[0323] 39: Conventional projected image display components

[0324] 40: Light guide component

[0325] 41: Reflective component.

Claims

1. A multilayer laminated film, comprising three or more resin layers arranged in a regular pattern, wherein the dielectric constant of each layer at a loss energy of 2.5 eV, as determined by electron energy loss spectroscopy (EELS), is denoted as dielectric constant X. i And from the dielectric constant X i When the larger layers are sequentially designated as layer A, layer B, and layer C, all of the following conditions (1) to (3) must be met, wherein, The above dielectric constant X i In the range i = 1, 2, 3, ..., (1) It has a repeating unit structure formed by stacking repeating units, and the repeating units are arranged in the order of A layer / B layer / C layer / B layer; (2) The repeating units within the total layer thickness of each repeating unit in the range of 250 nm or more and 630 nm or less are 80% or more and 100% or less with respect to all repeating units; (3) The multi-layer laminate film is composed of such a combination that the A layer is a crystalline thermoplastic resin layer, and the B layer and the C layer are amorphous thermoplastic resin layers.

2. The multi-layer laminate film according to claim 1, the lamination ratio of the total thickness of the A layer to the total thickness of the B layer within each repeating unit, i.e., A / B, and the lamination ratio of the total thickness of the C layer to the total thickness of the B layer within each repeating unit, i.e., C / B, are respectively 80% or more and 100% or less with respect to all repeating units within the range of 0.8 or more and 1.3 or less.

3. A multilayer laminated film having a repeating unit structure formed by stacking repeating units, wherein the repeating unit is defined as having a dielectric constant X, which is obtained by electron energy loss spectroscopy (EELS) at a loss energy of 2.5 eV. i When, the dielectric constant X i The three different resin layers, namely layer A, layer B, and layer C, are arranged in the order of layer A / layer B / layer C / layer B. The units within the total layer thickness of the repeating unit in the range of 250 nm or more and 630 nm or less are 80% or more and 100% or less with respect to all repeating units, The repeating units within the total layer thickness of the repeating unit in the range of 250 nm or more and 630 nm or less, the lamination ratio of the total thickness of the A layer to the total thickness of the B layer within each repeating unit, i.e., A / B, and the lamination ratio of the total thickness of the C layer to the total thickness of the B layer within each repeating unit, i.e., C / B, are respectively 80% or more and 100% or less with respect to all repeating units within the range of 0.8 or more and 1.3 or less. The dielectric constant X i In this context, the dielectric constant of layer A is set as X. A The dielectric constant of the B layer is set to X. B And the dielectric constant of the C layer is set to X. c When X is satisfied A >X B >X C , The average visible light reflectance of the P wave when incident at an angle of 60° with respect to the normal of the film surface is 10% or more and 99% or less.

4. The multi-layer laminate film according to any one of claims 1 to 3, the number of units within the total layer thickness of the repeating unit in the range of 250 nm or more and 630 nm or less is 15 or more and 2500 or less.

5. The multi-layer laminate film according to claim 3 or 4, which is composed of such a combination that the A layer is a crystalline thermoplastic resin layer, and the B layer and the C layer are amorphous thermoplastic resin layers.

6. The multilayer film according to any one of claims 1 to 5, wherein the planar orientation factor of layer A is 0.06 or higher, and the dielectric constant X of layer B is... B In this case, the ratio obtained by dividing the difference between the dielectric constant in the in-plane direction and the dielectric constant in the direction perpendicular to the plane by the dielectric constant in the direction perpendicular to the plane is less than 10%.

7. The multi-layer laminate film according to any one of claims 1 to 6, the chroma of the transmitted light incident perpendicularly to the film surface is 10 or less.

8. The multi-layer laminate film according to any one of claims 1 to 7, the transmittance of visible light incident perpendicularly to the film surface is 70% or more and 100% or less.

9. The multi-layer laminate film according to any one of claims 1 to 8, when light is incident on the film surface at an angle of 10° with respect to the normal of the film surface, in the wavelength range of 850 nm to 1600 nm, the reflectance is 40% or more in at least a wavelength range of 100 nm.

10. The multi-layer laminate film according to any one of claims 1 to 9, when the average reflectances when the P wave in the visible light band is incident on the film surface at angles of 20°, 40°, and 60° with respect to the normal of the film surface are respectively set as Rp20, Rp40, and Rp60, the relationship Rp20 ≤ Rp40 < Rp60 is satisfied, where Rp20, Rp40, and Rp60 are all in the form of %.

11. The multilayer laminated film according to any one of claims 1 to 10, wherein the chroma of the reflected light from a P-wave incident at an angle of 60° relative to the normal to the film surface is 20 or less.

12. The multilayer laminated film according to any one of claims 1 to 11, wherein the average reflectivity when a P-wave in the visible light band is incident on the film surface at an angle of 60° with the normal to the film surface is set as Rp60, the azimuth angle deviation of Rp60 is less than 10%, wherein Rp60 is expressed in the form of %.

13. In the multilayer film according to claims 1 to 12, among all layers in the multilayer film with a thickness of less than 1000 nm, the ratio T of the total thickness DA of layer A to the total thickness DB of layer B, i.e., T = DA / DB, satisfies 0.80 ≤ T ≤ 1.00, and the ratio S of the total thickness DC of layer C to the total thickness S of layer B, i.e., S = DC / DB, satisfies 1.10 ≤ S ≤ 1.

30.

14. A projection image display component, wherein, The multilayer laminated film according to any one of claims 1 to 13 is located on at least one side of the transparent support or between transparent components.

15. The projection image display component according to claim 14, wherein the thickness of the projection image display component is 0.5 mm or more and 7 mm or less, and the transparent support contains at least one of glass, polycarbonate resin, and acrylic resin.

16. A projection image display device comprising a projection image display component as described in claim 14 or 15, and a light source for illuminating its display surface.

17. In the projection image display device according to claim 15, the intensity of the P-wave in the image incident on the display surface of the projection image display member, i.e., the intensity of the P-wave / (intensity of the P-wave + intensity of the S-wave), is 51% or more.

18. The projection image display device according to claim 16 or 17, which is mounted on the head of a user for use.

19. A means of transport comprising the projection image display device of claim 16 or 17, wherein at least a portion of light emitted from the light source toward the projection image display member is incident on the projection image display member at an angle of 50° to 75° relative to the normal of the projection image display member.

20. The vehicle according to claim 19, wherein the projected image display device has a horizontal radius of curvature of 1m or more and 8m or less at the center of the projected image display component.

21. A building having the projection image display device as described in claim 16 or 17.

Images