Laminated glass for vehicle

Abstract

The present invention suppresses deterioration in the appearance of a liquid crystal light control film due to external light, and suppresses ultraviolet irradiation of an occupant in a vehicle.　The present invention includes: a first glass plate 10A that is located on the vehicle exterior side; a second glass plate 10B that located on the vehicle interior side; a liquid crystal light control film 14 that is provided between the first glass plate 10A and the second glass plate 10B and is capable of changing visible light transmittance in accordance with the state of application of a voltage; a first intermediate layer 12A that is located between the first glass plate 10A and the liquid crystal light control film 14; and a second intermediate layer 12B that is located between the second glass plate 10B and the liquid crystal light control film 14. The liquid crystal light control film 14 contains a dichroic dye. In a cross-sectional view of the first glass plate 10A and the second glass plate 10B, a vehicle exterior-side portion 51 located further to the vehicle exterior side than the liquid crystal light control film 14 has a light transmittance of 5% or less at a wavelength of 400 nm.

Description

Laminated glass for vehicles

[0001] This disclosure relates to laminated glass for vehicles.

[0002] Laminated glass with a dimmable film that allows for changing the visible light transmittance is known as an interlayer for use in vehicle windows such as automobiles and trains. In such vehicle laminated glass, to improve the privacy of occupants, for example, turning off the dimmable film scatters light and makes it appear like frosted glass, while turning on the dimmable film improves transparency. A liquid crystal element is used as the dimmable film (see, for example, Patent Document 1 below).

[0003] For example, Patent Document 1 describes a configuration using a liquid crystal dimming film. Patent Document 1 also discloses the addition of a dichroic dye (polychroic dye) to the liquid crystal material in order to increase the range of change in light transmittance associated with dimming switching.

[0004] Patent No. 3296096

[0005] However, a problem exists in that the liquid crystal material and dichroic dyes in the light-adjusting film are susceptible to ultraviolet (UV) light, and the UV light contained in ambient light causes the liquid crystal material and dichroic dyes to deteriorate over time, leading to a deterioration in the appearance of the light-adjusting film. Furthermore, for laminated glass used in vehicles, it is desirable to suppress the exposure of people (passengers) inside the vehicle to UV light that has passed through the glass.

[0006] This disclosure has been made in view of the above, and aims to provide laminated glass for vehicles that contains a liquid crystal dimming film, which suppresses deterioration of the appearance of the liquid crystal dimming film due to external light, and also suppresses the irradiation of ultraviolet rays to occupants inside the vehicle.

[0007] The laminated glass for vehicles according to this disclosure comprises a first glass plate located on the outside of the vehicle, a second glass plate located on the inside of the vehicle, a liquid crystal dimming film provided between the first glass plate and the second glass plate and capable of changing the visible light transmittance according to the voltage applied, a first intermediate layer located between the first glass plate and the liquid crystal dimming film, and a second intermediate layer located between the second glass plate and the liquid crystal dimming film, wherein the liquid crystal dimming film contains a dichroic dye, and in a cross-sectional view of the first glass plate and the second glass plate, the outer portion located on the outside of the vehicle beyond the liquid crystal dimming film has a light transmittance of 5% or less at a wavelength of 400 nm.

[0008] According to this disclosure, it is possible to suppress the deterioration of the appearance of the liquid crystal dimming film due to external light, and also to suppress the irradiation of ultraviolet rays to passengers inside the vehicle.

[0009] Figure 1 is a schematic plan view of the laminated glass for vehicles according to this embodiment. Figure 2 is a schematic cross-sectional view of the laminated glass for vehicles according to this embodiment. Figure 3 is a schematic cross-sectional view of the laminated glass for vehicles according to an example configuration in which a coating having an ultraviolet cut function is provided on the first glass plate. Figure 4 is a configuration diagram showing an example in which the first intermediate layer is a resin film to which an ultraviolet shielding additive has been added. Figure 5 is a configuration diagram showing an example in which the first intermediate layer is a multilayer film of a resin film and an ultraviolet shielding film. Figure 6 is a diagram showing an example configuration of a sound insulation film having a multilayer structure. Figure 7 is a schematic cross-sectional view of the light-adjusting film according to this embodiment.

[0010] Preferred embodiments of the present disclosure will be described in detail below with reference to the attached drawings. However, this disclosure is not limited to these embodiments, and if there are multiple embodiments, they may be combinations of these embodiments.

[0011] (Laminated Glass for Vehicles) Figure 1 is a schematic plan view of the laminated glass for vehicles according to this embodiment. Figure 2 is a schematic cross-sectional view of the laminated glass for vehicles according to this embodiment. The laminated glass for vehicles 1 according to this embodiment is laminated glass for vehicles. The laminated glass for vehicles 1 can be applied to, for example, the roof glass, rear glass, rear side glass, rear quarter glass, extra glass, windshield, etc. for vehicles. Extra glass is glass installed on the rear side of a vehicle to improve the driver's rearward visibility. Here, "vehicle" typically refers to an automobile, but also includes trains, ships, aircraft, etc., and refers to any moving object with glass.

[0012] In Figures 1 and 2, the laminated glass for vehicles 1 is shown as a flat plate, but it is not limited to this shape and may be curved in one or more directions. Also, in Figure 1, the planar shape of the laminated glass for vehicles 1 is shown as rectangular, but the planar shape of the laminated glass for vehicles 1 is not limited to a rectangle and may be any shape including a trapezoid or a triangle. Here, the planar shape refers to the shape of a predetermined area of ​​the laminated glass for vehicles 1 as viewed from the normal direction of the surface 10Bb of the second glass plate 10B, which will be described later. Furthermore, the planar view hereafter refers to viewing a predetermined area of ​​the laminated glass for vehicles 1 in the Z direction (i.e., from the normal direction of the interior surface of the laminated glass for vehicles 1), which will be described later.

[0013] As shown in Figure 2, the laminated glass for vehicles 1 comprises a first glass plate 10A, a second glass plate 10B, an intermediate layer 12, a liquid crystal dimming film 14, a heat insulating layer 18, and a shielding layer 19. Note that the heat insulating layer 18 and the shielding layer 19 are not essential components. Here, the direction in which the first glass plate 10A and the second glass plate 10B are laminated (the lamination direction in which each layer of the liquid crystal dimming film 14 is laminated) is defined as the Z direction, the direction from the second glass plate 10B toward the first glass plate 10A within the Z direction is defined as the Z1 direction, and the direction from the first glass plate 10A toward the second glass plate 10B within the Z direction (the direction opposite to the Z1 direction) is defined as the Z2 direction. Furthermore, one direction perpendicular to the Z direction is defined as the Y direction, and the direction perpendicular to both the Z and Y directions is defined as the X direction.

[0014] The laminated glass for vehicles 1 is laminated in the order of second glass plate 10B, intermediate layer 12, and first glass plate 10A, oriented in the Z1 direction. The liquid crystal dimming film 14 is provided within the intermediate layer 12. If a heat insulating layer 18 is provided, the laminated glass for vehicles 1 is laminated in the order of heat insulating layer 18, second glass plate 10B, intermediate layer 12, and first glass plate 10A, oriented in the Z1 direction. In this embodiment, the Z1 direction is the direction from the inside to the outside of the vehicle when the laminated glass for vehicles 1 is installed in a vehicle. The Z2 direction is the direction from the outside to the inside of the vehicle when the laminated glass for vehicles 1 is installed in a vehicle. That is, the first glass plate 10A is the glass plate that faces the outside of the vehicle when the laminated glass for vehicles 1 is installed in a vehicle, and the second glass plate 10B is the glass plate that faces the inside of the vehicle when the laminated glass for vehicles 1 is installed in a vehicle. Therefore, hereafter, "outside of the vehicle" means the side in the Z1 direction, and "inside of the vehicle" means the side in the Z2 direction. Furthermore, if the vehicle laminated glass 1 is curved, it is preferable that the vehicle laminated glass 1 is curved so as to be convex in the Z1 direction. That is, in this case, the vehicle laminated glass 1 can be said to be convex toward the outside of the vehicle when it is installed in the vehicle.

[0015] The total thickness T0 of the laminated glass 1 for vehicles is 2.8 mm or more and 10 mm or less, and preferably 5.8 mm or more within this range. If the total thickness T0 of the laminated glass 1 for vehicles is 2.8 mm or more, sufficient rigidity can be ensured. If the total thickness T0 of the laminated glass 1 for vehicles is 5.8 mm or more, ultraviolet light transmittance can be sufficiently reduced. Furthermore, if the total thickness of the laminated glass 1 for vehicles is 10 mm or less, sufficient visible light transmittance can be obtained and haze (clouding) can be reduced. The total thickness T0 of the laminated glass 1 for vehicles may be 8.0 mm or less, or 7.0 mm or less within this range. Note that the total thickness here, and the thickness described below, refers to the length in the Z direction.

[0016] In this specification, the portion of the first glass plate 10A and the second glass plate 10B located on the outside of the vehicle side of the liquid crystal dimming film 14 in a cross-sectional view (see Figure 2) is referred to as the exterior portion 51. In this embodiment, the exterior portion 51 includes the first glass plate 10A and the first intermediate layer 12A described later, and further includes the exterior shielding layer 19 if the shielding layer 19 is formed on the outer periphery of the exterior portion. The exterior portion 51 also includes any additional layers or members provided on the outside of the liquid crystal dimming film 14 in the laminated glass for vehicles 1. In this specification, the portion of the first glass plate 10A and the second glass plate 10B located on the inside of the vehicle side of the liquid crystal dimming film 14 in a cross-sectional view is referred to as the interior portion 52. In this embodiment, the interior portion 52 includes the second glass plate 10B, the heat insulating layer 18, and the second intermediate layer 12B described later, and further includes the interior shielding layer 19 if the shielding layer 19 is formed on the outer periphery of the exterior portion. The interior portion 52 includes any additional layers or components provided on the interior side of the vehicle's laminated glass 1 beyond the liquid crystal dimming film 14. The liquid crystal dimming film 14 is not included in either the exterior portion 51 or the interior portion 52.

[0017] (Glass Plates) The first glass plate 10A and the second glass plate 10B are glass plates facing each other. The intermediate layer 12 and the liquid crystal dimming film 14 are located between the first glass plate 10A and the second glass plate 10B. The first glass plate 10A and the second glass plate 10B are fixed together with the intermediate layer 12 and the liquid crystal dimming film 14 sandwiched between them. In this embodiment, the surface 10Aa of the first glass plate 10A in the Z1 direction becomes the surface 1A of the laminated vehicle glass 1 in the Z1 direction, and is the exterior surface of the laminated vehicle glass 1. Also in this embodiment, the surface 18B of the heat insulating layer 18 in the Z2 direction becomes the surface 1B of the laminated vehicle glass 1 in the Z2 direction, and is the interior surface of the laminated vehicle glass 1. However, if the heat insulating layer 18 is not provided, the surface 10Bb of the second glass plate 10B in the Z2 direction becomes the surface 1B of the laminated vehicle glass 1 in the Z2 direction, and is the interior surface of the laminated vehicle glass 1. Hereafter, when the first glass plate 10A and the second glass plate 10B are not distinguished, they will be referred to as glass plate 10 as appropriate.

[0018] The glass plate 10 may be either inorganic glass or organic glass. As the inorganic glass, for example, soda lime glass, aluminosilicate glass, borosilicate glass, alkali-free glass, quartz glass and the like are used without particular limitation. From the viewpoint of scratch resistance, the first glass plate 10A located on the vehicle exterior side is preferably inorganic glass, and is preferably soda lime glass from the viewpoint of formability. When the glass plate 10 is soda lime glass, clear glass, green glass containing a predetermined amount or more of an iron component, UV-cut green glass, and dark-colored privacy glass can be suitably used. The inorganic glass may be either untempered glass or tempered glass. The untempered glass is obtained by forming molten glass into a plate shape and then gradually cooling the same.

[0019] Privacy glass is a dark-colored glass having lower transparency than green glass and clear glass, and is also referred to as dark gray glass. Privacy glass contains Fe ２ O ３ This can be achieved by adjusting the content of total iron converted to . The visible light transmittance of privacy glass can be adjusted to, for example, about 40% to 50% when the plate thickness is 1.8 mm, and about 30% to 45% when the plate thickness is 2.0 mm.

[0020] An example of the composition of privacy glass is as follows, expressed in mass% based on oxide, as the base glass composition: SiO ２ : 66 to 75%, Na ２ O: 10 to 20%, CaO: 5 to 15%, MgO: 0 to 6%, Al ２ O ３ : 0 to 5%, K ２ O: 0 to 5%, FeO: 0.13 to 0.9%, total iron expressed as Fe ２ O ３ : 0.8% or more and less than 2.4%, TiO ２ : more than 1% and 5% or less; and based on the total amount of the components of the base glass composition, contains 100 to 500 ppm by mass of CoO, 0 to 70 ppm by mass of Se, and Cr ２ O ３ : 0 to 800 ppm by mass, and CoO, Se and Cr ２ O ３The total amount is less than 0.1% by mass.

[0021] Privacy glass is described in detail, for example, in International Publication No. 2015 / 088026, and its contents can be referenced herein.

[0022] Tempered glass is made by forming a compressive stress layer on the surface of untempered glass. Tempered glass can be either physically tempered glass, such as air-cooled tempered glass, or chemically tempered glass. In the case of physically tempered glass, the glass surface can be strengthened by creating a compressive stress layer on the glass surface through a temperature difference between the glass surface and the interior of the glass, for example, by rapidly cooling a uniformly heated glass plate from a temperature near its softening point during bending, rather than by slow cooling.

[0023] On the other hand, examples of materials for organic glass include polycarbonate, acrylic resins such as polymethyl methacrylate, polyvinyl chloride, and polystyrene.

[0024] The shape of the glass plate 10 is not particularly limited to a rectangular shape, and may be processed into various shapes and curvatures. Gravity forming, press forming, roller forming, etc., can be used to bend the glass plate 10. The method of forming the glass plate 10 is also not particularly limited, but for example, in the case of inorganic glass, a glass plate formed by the float method is preferred.

[0025] The thickness T1 of the first glass plate 10A is not particularly limited, but generally it can be appropriately selected within the range of 0.1 mm to 10 mm depending on the type and part of the vehicle to which the laminated glass for vehicles 1 is applied. Within this range, the thickness T1 of the first glass plate 10A is preferably 0.3 mm or more, which ensures sufficient strength such as resistance to flying stones while maintaining appropriate impact resistance. It is preferably 0.5 mm or more, more preferably 0.7 mm or more, particularly preferably 1.1 mm or more, and most preferably 2.0 mm or more. Within this range, a thickness T1 of the first glass plate 10A of 2.0 mm or more ensures sufficient impact resistance of the exterior portion 51 of the vehicle including the first glass plate 10A. Furthermore, within this range, a thickness T1 of the first glass plate 10A of 3 mm or less is preferable in terms of vehicle fuel efficiency because the mass of the laminated glass for vehicles 1 does not become too large. The thickness T1 of the first glass plate 10A is more preferably 2.6 mm or less, and particularly preferably 2.1 mm or less, within this range. It is preferable that the thickness T1 here is the thickness of the thinnest part of the first glass plate 10A.

[0026] The same applies to the thickness T2 of the second glass plate 10B as to the thickness T1 of the first glass plate 10A. The second glass plate 10B may have a different composition or thickness than the first glass plate 10A. For example, the second glass plate 10B may be thinner than the first glass plate 10A.

[0027] If the thickness T2 of the second glass plate 10B is 1.1 mm or less within this range, it is preferable from the viewpoint of strength that the second glass plate 10B is chemically strengthened glass.

[0028] The surface of the glass plate 10 (at least one of the first glass plate 10A and the second glass plate 10B) may be provided with a functional layer having a function other than the heat insulating layer 18. The functional layer is a member that provides additional functions to the glass plate. The functional layer may be a coating with water-repellent properties, a coating with ultraviolet-cutting properties, a coating with low reflectivity properties, a coating with antifouling properties, a coating with condensation prevention properties, a coating that absorbs visible light, or a colored coating. For example, a coating with water-repellent properties (functional layer) is preferably provided on the outer surface 10Aa of the first glass plate 10A, and a coating with low reflectivity properties (functional layer) is preferably provided on the inner surface 10Bb of the second glass plate 10B. That is, the glass plate 10 (at least one of the first glass plate 10A and the second glass plate 10B) may have one or more of the following: a water-repellent layer, an ultraviolet-blocking layer, a low reflectivity layer, an antifouling layer, a condensation prevention layer, a visible light absorption layer, or a colored layer. Furthermore, the heat insulating layer 18 can also be described as a type of functional layer consisting of a coating (infrared reflective layer) with low emissivity characteristics.

[0029] FIG. 3 is a schematic cross-sectional view of a laminated glass for a vehicle according to a configuration example in which a coating 60 having an ultraviolet blocking function is provided on a first glass plate 10A. In the example of FIG. 3, a coating 60 having an ultraviolet blocking function (i.e., a UV cut coat) is provided on the surface of the first glass plate 10A. The coating 60 having an ultraviolet blocking function is provided on the surface 10Ab of the first glass plate 10A in the Z2 direction. In addition to the example shown in FIG. 3, the coating having an ultraviolet blocking function may be provided on the surface 10Aa of the first glass plate 10A in the Z1 direction, or may be provided on both the surface 10Aa and the surface 10Ab. In the present embodiment, the coating 60 having an ultraviolet blocking function is an ultraviolet shielding layer containing an ultraviolet absorber. The film thickness of the coating 60 having an ultraviolet blocking function is, for example, 1 µm or more and 10 µm or less. Examples of the ultraviolet absorber include triazine-based ultraviolet absorbers, benzotriazole-based ultraviolet absorbers, benzophenone-based ultraviolet absorbers, azomethine-based ultraviolet absorbers, indole-based ultraviolet absorbers, benzodithiol-based ultraviolet absorbers, and oxazolone-based ultraviolet absorbers. The ultraviolet absorber is preferably one or more selected from azomethine-based ultraviolet absorbers, indole-based ultraviolet absorbers, and benzodithiol-based ultraviolet absorbers. This makes it possible to efficiently block ultraviolet rays of 380 nm to 400 nm. For example, the coating 60 having an ultraviolet blocking function can be formed by applying a mixed solution containing at least the above-described ultraviolet absorber to the surface of a glass plate, drying the solution, and firing the same as necessary.

[0030] It should be noted that in the present embodiment, the laminated glass for a vehicle 1 is a laminated glass for a vehicle having two glass plates, the first glass plate 10A and the second glass plate 10B, but the number of glass plates is not limited thereto and may be three or more.

[0031] (Intermediate Layer) The intermediate layer 12 is disposed between a first glass plate 10A and a second glass plate 10B. As shown in FIG. 2, the intermediate layer 12 includes, for example, a first intermediate layer 12A bonded to the first glass plate 10A and a second intermediate layer 12B bonded to the second glass plate 10B. A liquid crystal light control film 14 is provided between the first intermediate layer 12A and the second intermediate layer 12B in the Z direction. In other words, the first intermediate layer 12A is a film located between the first glass plate 10A and the liquid crystal light control film 14, and the second intermediate layer 12B can also be said to be a film located between the second glass plate 10B and the liquid crystal light control film 14.

[0032] In the present embodiment, the intermediate layer 12 further includes a frame-shaped third intermediate layer 12C positioned between the first intermediate layer 12A and the second intermediate layer 12B and surrounding the outer periphery of the liquid crystal light control film 14. However, the intermediate layer 12 does not necessarily need to include the third intermediate layer 12C. Even when the intermediate layer 12 does not include the third intermediate layer 12C, the outer periphery of the liquid crystal light control film 14 is surrounded by at least one of the first intermediate layer 12A and the second intermediate layer 12B during pressure bonding in the manufacturing process of the laminated glass for vehicles 1.

[0033] The material of the intermediate layer 12 may be arbitrary, and for example, a thermoplastic resin may be used. Examples of the thermoplastic resin include polyvinyl butyral resin obtained by reacting PVA with n-butyraldehyde (hereinafter may be referred to as "PVB" as necessary), ethylene-vinyl acetate copolymer resin (hereinafter may be referred to as "EVA" as necessary), and the like. PVB may contain a plasticizer. Note that as the thermoplastic resin, for example, a polyurethane resin, a cycloolefin polymer resin, an ionomer resin, or the like may also be used. The materials for the intermediate layer may be used alone, or two or more types may be used in combination.

[0034] As the intermediate layer 12, a curable transparent resin, also known as Optically Clear Resin (OCR) or Liquid Optically Clear Adhesive (LOCA), or a transparent adhesive sheet, also known as Optically Clear Adhesive (OCA), may be used. By using a curable transparent resin or a transparent adhesive sheet, it becomes possible to fabricate a laminate at room temperature. Acrylic, silicone, urethane acrylate, and epoxy resins can be used as curable transparent resins or transparent adhesive sheets. These curable transparent resins and transparent adhesive sheets may be used individually or in combination of two or more types.

[0035] However, the material forming the intermediate layer 12 is not limited to thermoplastic resin. The intermediate layer 12 may also contain functional particles such as infrared absorbers, ultraviolet shielding additives, and light-emitting agents. Furthermore, the intermediate layer 12 (first intermediate layer 12A and second intermediate layer 12B) may be colored. For example, the intermediate layer 12 may contain a coloring agent to adjust the appearance (color) of the laminated glass 1 for vehicles. The intermediate layer 12 may also have a partially colored area called a shade band, in which the visible light transmittance is typically in the range of 5% to 50%.

[0036] The thickness of the intermediate layer 12 is preferably 0.3 mm or more and 3 mm or less. If the thickness of the thinnest part of the intermediate layer 12 is 0.3 mm or more at its thinnest part, the impact resistance required for vehicle laminated glass 1 will be sufficient. If the maximum thickness of the intermediate layer 12 is 3 mm or less, the mass of vehicle laminated glass 1 will not become too large. Within this range, the maximum thickness of the intermediate layer 12 is more preferably 2.8 mm or less, and even more preferably 2.6 mm or less. Note that the thickness of the intermediate layer 12 refers to the thickness of the intermediate layer 12 only, excluding the thickness of the liquid crystal dimming film 14. Therefore, the thickness of the intermediate layer 12 refers to the length obtained by subtracting the thickness T4 of the liquid crystal dimming film 14 from the thickness T3 from the surface of the second intermediate layer 12B facing the second glass plate 10B to the surface of the first intermediate layer 12A facing the first glass plate 10A.

[0037] The intermediate layer 12 may be a single layer, or it may have two or more layers, particularly three or more layers. Furthermore, the first intermediate layer 12A, the second intermediate layer 12B, and the third intermediate layer 12C may all be formed from the same material, or at least one of the first intermediate layer 12A, the second intermediate layer 12B, and the third intermediate layer 12C may be formed from a different material. That is, the first intermediate layer 12A, the second intermediate layer 12B, and the third intermediate layer 12C may be formed as a single unit, or they may be formed as separate units. In this embodiment, a part of the first intermediate layer 12A or the second intermediate layer 12B is molded to surround the outer periphery of the liquid crystal dimming film 14, but the first intermediate layer 12A and the second intermediate layer 12B may be molded to the same size as the liquid crystal dimming film 14.

[0038] In this embodiment, it is preferable that the first intermediate layer 12A has an ultraviolet shielding function, that is, an optical property with low light transmittance at wavelengths in the ultraviolet region. This reduces the amount of ultraviolet light that passes through the exterior portion 51 and incident on the liquid crystal dimming film 14. As an indicator of the ultraviolet shielding function, the light transmittance at any wavelength in the ultraviolet region can be used. For example, in this specification, the light transmittance at a wavelength of 400 nm is used as an indicator of the ultraviolet shielding function. Note that the first intermediate layer 12A does not have to have an ultraviolet shielding function. In particular, as in the configuration example shown in Figure 3, if the components of the exterior portion 51 other than the first intermediate layer 12A have an ultraviolet shielding function, the first intermediate layer 12A does not have to have an ultraviolet shielding function.

[0039] The first intermediate layer 12A, which has an ultraviolet shielding function, includes, for example, at least one of a resin film 42 to which an ultraviolet shielding additive 41 is added, and a multilayer film of a resin film 43 and an ultraviolet shielding film 44. Figure 4 is a configuration diagram showing an example in which the first intermediate layer is a resin film to which an ultraviolet shielding additive is added. Figure 5 is a configuration diagram showing an example in which the first intermediate layer is a multilayer film of a resin film and an ultraviolet shielding film.

[0040] In the example shown in Figure 4, the first intermediate layer 12A is composed of a resin film 42 to which an ultraviolet shielding additive 41 is added. The ultraviolet shielding additive 41 is a substance that shields ultraviolet rays by absorbing or reflecting (scattering) them. As the resin film 42, various materials such as PVB, which were exemplified as the material for the intermediate layer 12, can be used. The method of adding the ultraviolet shielding additive 41 is not particularly limited. For example, the ultraviolet shielding additive 41 may be added directly to the resin material, or it may be added to a solvent such as a plasticizer and then mixed before use. The ultraviolet shielding additive 41 is preferably at least one ultraviolet absorber selected from the group consisting of benzotriazole compounds, triazine compounds, dibenzoylresorcinol derivatives, benzophenone compounds, benzodithiol compounds, azomethine compounds, indole compounds, oxazolone compounds, benzoate compounds, malonic acid ester compounds, and oxalic acid anilide compounds. The ultraviolet shielding additive 41 may also be a metal oxide absorber. The above-mentioned UV absorbers may be used individually or in combination of two or more. Examples of benzotriazole-based UV absorbers include "Tinuvin® P", "Tinuvin® 326", "Tinuvin® 328", and "Tinuvin® 329" manufactured by BASF. Examples of metal oxide-based UV absorbers include zinc oxide, titanium oxide, and cerium oxide. The surface of the metal oxide-based UV absorber may be coated with silica, hydrolyzable organosilicon compounds, or silicone compounds. The amount of UV shielding additive added is not particularly limited, but it is preferable to include 0.01 parts by weight or more and 5.0 parts by weight or less, and more preferably 0.05 parts by weight or more, per 100 parts by weight of the transparent resin constituting the resin film, to easily obtain a UV absorption effect. Furthermore, it is preferable to include 1.0 part by weight or less of the UV shielding additive per 100 parts by weight of the transparent resin constituting the resin film, within this range, to easily suppress weather-resistant degradation of the transparent resin itself. Furthermore, the resin film 42 to which the ultraviolet shielding additive 41 is added may also contain an infrared shielding additive.As infrared shielding additives, inorganic infrared shielding additives such as antimond-doped tin oxide nanoparticles (ATO nanoparticles), tin-doped indium oxide nanoparticles (ITO nanoparticles), and near-infrared absorbing nanoparticles CWO (registered trademark) manufactured by Sumitomo Metal Mining Co., Ltd. may be used, or phthalocyanine-based or naphthalocyanine-based organic infrared shielding additives may be used, or these may be used in combination.

[0041] In the example shown in Figure 5, the first intermediate layer 12A is composed of a multilayer film of a resin film 43 and an ultraviolet shielding film 44. The resin film 43 can be any of the various materials described above as examples for the intermediate layer 12. The ultraviolet shielding film 44 can be any film containing at least one ultraviolet absorber selected from the group consisting of salicylate compounds, benzophenone compounds, benzotriazole compounds, and substituted acrylonitrile compounds. The ultraviolet absorber can be contained on the surface or inside the transparent resin material. The thickness of the ultraviolet shielding film 44 is, for example, 10 μm to 200 μm, preferably 20 μm to 100 μm.

[0042] The first intermediate layer 12A is preferably 0.38 mm or more and 0.9 mm or less in thickness, and more preferably 0.76 mm or more in thickness within this range. When the first intermediate layer 12A has an ultraviolet shielding function, the ultraviolet transmittance can be effectively reduced. The first intermediate layer 12A is more preferably 0.8 mm or less in thickness within this range. This suppresses the occurrence of foaming and plate displacement at the interface of the first intermediate layer 12A.

[0043] The second intermediate layer 12B does not necessarily have to have an ultraviolet shielding function, but if the second intermediate layer 12B has an ultraviolet shielding function, it can reduce the overall ultraviolet transmittance of the laminated glass for vehicles 1 and reduce the amount of ultraviolet radiation irradiated to occupants inside the vehicle.

[0044] If the second intermediate layer 12B has an ultraviolet shielding function, the second intermediate layer 12B may have the same configuration as the first intermediate layer 12A. That is, the second intermediate layer 12B may include at least one of a resin film 42 to which an ultraviolet shielding additive 41 is added, and a multilayer film of a resin film 43 and an ultraviolet shielding film 44. The second intermediate layer 12B may have a different configuration from the first intermediate layer 12A.

[0045] The second intermediate layer 12B preferably has a thickness of 0.38 mm or more and 0.9 mm or less, and more preferably a thickness of 0.76 mm or more within this range. When the second intermediate layer 12B has an ultraviolet shielding function, the ultraviolet transmittance can be effectively reduced. The second intermediate layer 12B is more preferably 0.8 mm or less within this range. This suppresses the occurrence of foaming and plate displacement at the interface of the second intermediate layer 12B.

[0046] The intermediate layer 12 may have a sound-insulating function. That is, in one example, at least one of the first intermediate layer 12A and the second intermediate layer 12B includes a sound-insulating film 45 having a multilayer structure. This can improve the sound insulation of the laminated glass 1 for vehicles. Figure 6 is a diagram showing an example of the configuration of a sound-insulating film having a multilayer structure. The sound-insulating film 45 having a multilayer structure has a multilayer structure in which multiple layers with different hardnesses are laminated. In the example of Figure 6, the sound-insulating film 45 is composed of two high-hardness layers 45A (also called "skin layers") and one low-hardness layer 45B (also called "core layer") which has a lower hardness than the high-hardness layers 45A. The low-hardness layer 45B is placed between the two high-hardness layers 45A. By sandwiching the low-hardness layer 45B between the two high-hardness layers 45A, the sound-insulating film 45 has sound-insulating properties. Here, hardness is Shore hardness. The constituent materials of each layer of the sound-insulating film 45 are not particularly limited. For example, PVB can be used as the high-hardness layer 45A, and PVB with lower hardness than the high-hardness layer 45B can be used as the low-hardness layer 45B. The hardness of the PVB can be adjusted, for example, by the amount of plasticizer added. At least one of the high-hardness layer 45A and the low-hardness layer 45B that constitute the sound insulation film 45 may be a layer that has an ultraviolet shielding function. The intermediate layer 12 may separately comprise the sound insulation film 45 and a film that has an ultraviolet shielding function.

[0047] (Thermal insulation layer) The thermal insulation layer 18 is a film that has properties to suppress heat transfer, and is particularly a film with low emissivity properties. As shown in Figure 2, the thermal insulation layer 18 is provided on the in-vehicle side surface of the second glass plate 10B, that is, on the surface 10Bb in the Z2 direction. However, the position in which the thermal insulation layer 18 is provided is not limited to this. The thermal insulation layer 18 is preferably provided in the Z2 direction from the liquid crystal dimming film 14, and more preferably provided in the Z2 direction from the second intermediate layer 12B.

[0048] The thermal insulation layer 18 may be composed of any material that satisfies the characteristics described later, but may be a low-emissivity (Low-E) film. Examples of materials include tin-doped indium oxide (ITO), tin oxide, fluorine-doped tin oxide (FTO), antimond-doped tin oxide (ATO), silver, zirconium nitride, and titanium nitride. Among these, ITO, tin oxide, and FTO are preferred. These materials may be used individually or in combination of two or more. The thickness of each layer made of these materials is preferably 60 nm or more from the viewpoint of thermal insulation performance, and preferably 160 nm or less from the viewpoint of productivity. The thermal insulation layer 18 may also further include one or more dielectric layers. Examples of dielectrics include silicon and / or aluminum oxides, nitrides, and oxynitrides. When the thermal insulation layer 18 includes multiple layers, the total thickness of the thermal insulation layer 18 is preferably 100 nm to 800 nm, and more preferably 150 nm to 700 nm.

[0049] The heat insulating layer 18 can be formed using, for example, physical vapor deposition (PVD) methods such as sputtering, vacuum deposition, and ion plating, or chemical vapor deposition (CVD) methods.

[0050] The emissivity of the insulation layer 18 is preferably 0.4 or less, and more preferably 0.3 or less. This suppresses heat transfer to the interior of the vehicle. The emissivity is a value measured according to the measurement method in accordance with JIS R1801:2002.

[0051] (Shielding layer) As shown in Figures 1 and 2, the laminated glass for vehicles 1 may have a shielding layer 19. The shielding layer 19 is an opaque layer and can be provided in a strip shape along the periphery of the laminated glass for vehicles 1, for example. As shown in Figure 1, when viewed from the Z direction, the area AR1 of the entire area of ​​the laminated glass for vehicles 1 that does not overlap with the shielding layer 19 (the area surrounded by the shielding layer 19 in the example of Figure 1) can be said to be a light-transmitting area where visible light can pass through, and the area AR2 that overlaps with the shielding layer 19 can be said to be a shielding area where visible light is blocked.

[0052] The shielding layer 19 overlaps, for example, the peripheral edge of the glass plate 10 and the peripheral edge of the liquid crystal dimming film 14 when viewed from the Z direction. The shielding layer 19 is, for example, an opaque (e.g., black) colored ceramic. The shielding layer 19 may be a light-shielding colored interlayer or colored film, or a combination of a colored interlayer and colored ceramic. The colored film may be integrated with an infrared reflective film or the like. The colored interlayer or colored film may be colored as a whole, or its surface may be colored or painted.

[0053] The shielding layer 19 prevents the deterioration of the urethane or other resin that holds the peripheral edge of the laminated glass 1 for vehicles to the vehicle body due to ultraviolet rays. In addition, the shielding layer 19 conceals the power supply unit 30 and wiring 32, which will be described later, so that they are difficult to see from at least one of the outside and inside of the vehicle.

[0054] The shielding layer 19 can be formed, for example, by applying a ceramic color paste containing a molten glass frit containing a black pigment onto a glass plate by screen printing or the like, and then firing it, but is not limited to this. The shielding layer 19 may also be formed, for example, by applying an organic ink containing a black or dark-colored pigment onto a glass plate by screen printing or inkjet printing, and then drying it.

[0055] In the example shown in Figure 2, the shielding layer 19 is provided on the peripheral edge of the surface 10Ab of the first glass plate 10A in the Z2 direction and on the peripheral edge of the surface 10Bb of the second glass plate 10B in the Z2 direction (in this example, the surface of the heat insulating layer 18 in the Z2 direction). However, it is not limited to this, and the shielding layer 19 may be provided on the peripheral edge of at least one of the first glass plate 10A and the second glass plate 10B. For example, the shielding layer 19 may be provided on at least one of the peripheral edge of the surface 10Ab of the first glass plate 10A and on the peripheral edge of the surface 10Bb of the second glass plate 10B. Also, for example, the shielding layer 19 may be provided on the peripheral edge of the surface 10Aa of the first glass plate 10A in the Z1 direction, or on the peripheral edge of the surface 10Ba of the second glass plate 10B in the Z1 direction. Also, for example, the shielding layer 19 may be provided on the peripheral edge of the liquid crystal dimming film 14. Furthermore, when both a heat insulating layer 18 and a shielding layer 19 are provided on the surface 10Bb of the second glass plate 10B, the shielding layer 19 may be laminated in the Z1 direction more than the heat insulating layer 18. Also, the heat insulating layer 18 may be positioned to avoid the peripheral edge of the second glass plate 10B and not overlap with the shielding layer 19.

[0056] (Dimmable Film) As shown in Figure 2, the liquid crystal dimmable film 14 is provided between the first glass plate 10A and the second glass plate 10B in the Z direction, and more specifically, between the first intermediate layer 12A and the second intermediate layer 12B in the Z direction. The liquid crystal dimmable film 14 can change the visible light transmittance depending on the voltage applied. In this embodiment, the liquid crystal dimmable film 14 has a dimmable layer 24 containing liquid crystal elements, and the light transmittance and haze change as the orientation state of the liquid crystal elements contained in the dimmable layer 24 changes by the application of a voltage. The light transmittance of the dimmable layer 24 becomes relatively higher in one state of voltage application and relatively lower in the other state. The state of relatively high (or low) light transmittance may be achieved in either the voltage application state or the voltage non-application state. In one example, the light transmittance of the liquid crystal dimming film 14 when the voltage applied to the liquid crystal dimming film 14 is in the first state is lower than the light transmittance of the liquid crystal dimming film 14 when the voltage applied to the liquid crystal dimming film 14 is in the second state. In this embodiment, the first state refers to a state in which no voltage is applied to the liquid crystal dimming film 14, and the second state refers to a state in which the rated voltage is applied to the liquid crystal dimming film 14. The rated voltage is the voltage value applied to maximize the light transmittance of the liquid crystal dimming film 14, and this value is set appropriately depending on the object on which the laminated glass for vehicles 1 is mounted. For example, the rated voltage may be around 48V or around 100V. However, it is not limited to these, and for example, the first state may refer to a state in which the rated voltage is applied to the liquid crystal dimming film 14, and the second state may refer to a state in which no voltage is applied to the liquid crystal dimming film 14. In this case, the rated voltage is the voltage value applied to minimize the light transmittance of the liquid crystal dimming film 14.

[0057] The liquid crystal dimming film 14 may be placed over almost the entire surface of the laminated vehicle glass 1 when viewed from the Z direction. The planar shape of the liquid crystal dimming film 14 is, for example, a rectangle smaller than the planar shape of the laminated vehicle glass 1. However, the planar shape of the liquid crystal dimming film 14 does not have to be rectangular. It is preferable that the peripheral edge of the liquid crystal dimming film 14 is in a position that overlaps with the shielding layer 19 in a planar view.

[0058] Figure 7 is a schematic cross-sectional view of the dimming film according to this embodiment. As shown in Figure 7, the liquid crystal dimming film 14 has a first substrate 20A, a first electrode layer 22A, a dimming layer 24, a second electrode layer 22B, and a second substrate 20B. The liquid crystal dimming film 14 is laminated in the order of second substrate 20B, second electrode layer 22B, dimming layer 24, first electrode layer 22A, and first substrate 20A in the Z1 direction. Hereinafter, when the first substrate 20A and the second substrate 20B are not distinguished, they will be referred to as substrate 20, and when the first electrode layer 22A and the second electrode layer 22B are not distinguished, they will be referred to as electrode layer 22.

[0059] The thickness T4 of the liquid crystal dimming film 14 is, for example, 0.05 mm or more and 0.5 mm or less, and preferably 0.1 mm or more and 0.4 mm or less.

[0060] (Substrates) The first substrate 20A and the second substrate 20B are substrates that sandwich the light-adjusting layer 24. The first substrate 20A is positioned in the Z1 direction relative to the light-adjusting layer 24, and the second substrate 20B is positioned in the Z2 direction relative to the light-adjusting layer 24.

[0061] The base material 20 is preferably a transparent resin layer. The base material 20 preferably contains one or more selected from the group consisting of polyethylene terephthalate, polyethylene naphthalate, polyamide, polysulfone, polyethersulfone, polycarbonate, polystyrene, cyclic polyolefin, polyarylate, polyetherimide, polyetheretherketone, polyimide, aramid, polybutylene terephthalate, triacetylcellulose, polyurethane, and cycloolefin polymer.

[0062] The first base material 20A and the second base material 20B are, for example, made of the same material as described above, but are not limited to that, and may be made of different materials.

[0063] The thickness T5 of the base material 20 is, for example, 5 μm or more and 500 μm or less, preferably 10 μm or more and 200 μm or less, and more preferably 50 μm or more and 150 μm or less. If the base material 20 is thick, the possibility of foaming and residual foam increases, so by having a thickness T5 of 500 μm or less, the possibility of foaming and residual foam can be reduced. The first base material 20A and the second base material 20B have the same thickness T5, but their thicknesses may be different.

[0064] (Electrode Layers) The first electrode layer 22A is formed on the Z2 direction surface of the first substrate 20A and is in contact with the Z1 direction surface of the dimming layer 24. The second electrode layer 22B is formed on the Z1 direction surface of the second substrate 20B and is in contact with the Z2 direction surface of the dimming layer 24. In other words, the first electrode layer 22A and the second electrode layer 22B are electrode layers that sandwich the dimming layer 24. The first electrode layer 22A and the second electrode layer 22B are connected to the power supply unit 30 via wiring 32 and a voltage is applied from the power supply unit 30. The first electrode layer 22A is formed over the entire area of ​​the first substrate 20A, and the second electrode layer 22B is formed over the entire area of ​​the second substrate 20B. However, the shapes of the first electrode layer 22A and the second electrode layer 22B are arbitrary, and they do not have to be formed over the entire surface of the first substrate 20A and the second substrate 20B, nor do they have to be rectangular, such as having a comb-like shape.

[0065] For example, a transparent conductive oxide (TCO) can be used as the electrode layer 22. Examples of TCOs include, but are not limited to, tin-doped indium oxide (ITO), aluminum-doped zinc oxide (AZO), and fluorine-doped tin oxide (FTO).

[0066] Transparent conductive polymers such as poly(3,4-ethylenedioxythiophene) (PEDOT) or poly(4,4-dioctylcyclopentadithiophene) can also be suitably used as the electrode layer 22. Furthermore, laminated films of a metal layer and a dielectric layer, silver nanowires, silver or copper metal meshes, etc., can also be suitably used as the electrode layer 22.

[0067] (Light-adjusting layer) The light-adjusting layer 24 is a layer whose light transmittance and haze can be changed. The light-adjusting layer 24 is provided between the first electrode layer 22A and the second electrode layer 22B. The light-adjusting layer 24 may be provided with a sealing material (not shown) that seals the sides of the light-adjusting layer 24. In this embodiment, the liquid crystal light-adjusting film 14 includes polymer dispersed liquid crystal (PDLC) or guest-host liquid crystal (GHLC) as the light-adjusting layer 24.

[0068] Polymer-dispersed liquid crystals (PDLCs) are components having an active layer in which droplet-shaped liquid crystals are dispersed and held in a transparent polymer medium. Applying a voltage to the electrode layer changes the orientation of the liquid crystal molecules held in the active layer. As a result, the active layer changes the intensity of scattering of incident light according to the voltage applied to the electrode layer. The degree of light scattering can be expressed, for example, as haze. When the liquid crystals form a continuous phase and are held in the transparent polymer medium, it is also called a polymer network liquid crystal (PNLC), but PDLC in this disclosure is intended to encompass PNLC. Dichroic dyes that have anisotropy in light absorption in the long axis and short axis directions of the molecules can be added to droplet-shaped or continuous-phase liquid crystals, and such liquid crystal elements are known, for example, from Japanese Patent Application Publication No. 2020-126091.

[0069] Guest-host liquid crystal (GHLC) is a component having an active layer formed by mixing a dichroic dye (guest) with a liquid crystal material (host). Applying a voltage to the electrode layer changes the orientation of the liquid crystal molecules held in the active layer. As a result, the active layer changes the degree of absorption of incident light in accordance with the voltage applied to the electrode layer.

[0070] Furthermore, in this embodiment, the liquid crystal dimming film 14 contains a dichroic dye in the dimming layer 24. A dichroic dye is a dye that has the property of having different absorbances in the long axis direction and in the short axis direction of the molecule. The dichroic dye is configured so that its orientation changes in accordance with the change in the orientation of the liquid crystal molecules due to voltage. This increases the range of change in the light transmittance of the liquid crystal dimming film 14. Examples of dichroic dyes include azo dyes, anthraquinone dyes, perylene dyes, merocyanine dyes, azomethine dyes, naphthoquinone dyes, and tetrazine dyes. It is preferable to use at least one of azo dyes and anthraquinone dyes.

[0071] (Characteristics of Laminated Glass for Vehicles) In the laminated glass for vehicles 1 configured as described above, the outer portion 51 shown in Figure 2 has optical properties that reduce ultraviolet light transmittance. By reducing the ultraviolet light transmittance of the outer portion 51, ultraviolet light contained in ambient light is suppressed from entering the liquid crystal dimming film 14. Furthermore, by reducing the ultraviolet light transmission of the outer portion 51, ultraviolet light contained in ambient light is suppressed from passing through the laminated glass for vehicles 1 and irradiating occupants inside the vehicle. In this specification, when referring to the overall light transmittance of the laminated glass for vehicles 1, or the light transmittance of the outer portion 51 and the inner portion 52, the light transmittance refers to the light transmittance of the region AR1, that is, the portion not covered by the shielding layer 19.

[0072] (Exterior portion) As described above, the exterior portion 51 is the portion of the first glass plate 10A and the second glass plate 10B located on the exterior side of the vehicle, in a cross-sectional view, relative to the liquid crystal dimming film 14. The exterior portion 51 includes the first glass plate 10A and the first intermediate layer 12A. The exterior portion 51 may include other members other than the first glass plate 10A and the first intermediate layer 12A that are located on the exterior side of the vehicle relative to the liquid crystal dimming film 14. The optical properties of the exterior portion 51 are the overall optical properties of the exterior portion 51, which is composed of multiple members.

[0073] In this embodiment, the outer portion 51 has a light transmittance of 5% or less at a wavelength of 400 nm. Preferably, the light transmittance of the outer portion 51 at a wavelength of 400 nm is 4% or less, more preferably 3% or less, and even more preferably 2% or less. Furthermore, it is preferable that the light transmittance of the outer portion 51 at a wavelength of 400 nm is less than or equal to the light transmittance of the inner portion 52 at a wavelength of 400 nm. The light transmittance of the outer portion 51 at a wavelength of 400 nm may be the same as that of the inner portion 52 at a wavelength of 400 nm, or it may be lower than that of the inner portion 52 at a wavelength of 400 nm. The light transmittance can be obtained by measuring the spectral transmittance curve using a spectrophotometer or the like.

[0074] In this embodiment, the outer portion 51 preferably has a light transmittance of 2% or less at a wavelength of 390 nm. This more effectively suppresses deterioration of the appearance of the liquid crystal dimming film 14 due to ambient light. The light transmittance of the outer portion 51 at a wavelength of 390 nm is more preferably 1.5% or less, and even more preferably 1% or less. Furthermore, the light transmittance of the outer portion 51 at a wavelength of 390 nm is preferably less than or equal to the light transmittance of the inner portion 52 at a wavelength of 390 nm. The light transmittance of the outer portion 51 at a wavelength of 390 nm may be the same as that of the inner portion 52 at a wavelength of 390 nm, or it may be lower than that of the inner portion 52 at a wavelength of 390 nm.

[0075] In this embodiment, the exterior portion 51 of the vehicle preferably has a light transmittance at a wavelength of 420 nm that is at least twice, more preferably three times, and even more preferably four times, the light transmittance at a wavelength of 400 nm. This reduces the amount of ultraviolet light transmitted, including wavelength 400 nm, while suppressing a decrease in the amount of visible light transmitted at wavelengths of 420 nm or higher. For example, the exterior portion 51 of the vehicle preferably has a light transmittance at a wavelength of 420 nm that is at least 15%, more preferably 20% or higher, and even more preferably 25% or higher.

[0076] The visible light transmittance of the exterior portion 51 of the vehicle is preferably 25% to 80%, more preferably 30% to 75%, and even more preferably 35% to 70%. The visible light transmittance can be measured in accordance with the provisions of JIS R3106:2019 "Test methods for transmittance, reflectance, and emissivity of flat glass and calculation method for solar heat gain coefficient of building flat glass".

[0077] Next, the optical properties of the components constituting the exterior portion 51 of the vehicle will be described.

[0078] The first glass plate 10A has a light transmittance of 90% or less at 390 nm, preferably 40% or less, and more preferably 1% or less. The first glass plate 10A has a light transmittance of 93% or less at 400 nm, preferably 45% or less, and more preferably 2% or less. The first glass plate 10A has a light transmittance of 95% or less at 420 nm, preferably 45% or less, and more preferably 5% or less. The first glass plate 10A has a visible light transmittance of 40% or more, preferably 80% or more, and more preferably 90% or more.

[0079] The light transmittance of the first glass plate 10A at a wavelength of 400 nm is preferably less than or equal to the light transmittance of the second glass plate 10B at a wavelength of 400 nm. The light transmittance of the first glass plate 10A at a wavelength of 400 nm may be equal to the light transmittance of the second glass plate 10B at a wavelength of 400 nm. The light transmittance of the first glass plate 10A at a wavelength of 400 nm may be lower than the light transmittance of the second glass plate 10B at a wavelength of 400 nm.

[0080] The first intermediate layer 12A has a light transmittance of 10% or less at 390 nm, preferably 5% or less, and more preferably 1% or less. The first intermediate layer 12A has a light transmittance of 40% or less at 400 nm, preferably 10% or less, and more preferably 2% or less. The first intermediate layer 12A has a light transmittance of 93% or less at 420 nm, preferably 15% or less, and more preferably 3% or less. The first intermediate layer 12A has a visible light transmittance of 95% or less, preferably 50% or less, and more preferably 10% or less.

[0081] The light transmittance of the first intermediate layer 12A at a wavelength of 400 nm is preferably less than or equal to the light transmittance of the second intermediate layer 12B at a wavelength of 400 nm. The light transmittance of the first intermediate layer 12A at a wavelength of 400 nm may be equal to the light transmittance of the second intermediate layer 12B at a wavelength of 400 nm. The light transmittance of the first intermediate layer 12A at a wavelength of 400 nm may be lower than the light transmittance of the second intermediate layer 12B at a wavelength of 400 nm.

[0082] (Inside portion) As described above, the inside portion 52 is the portion of the first glass plate 10A and the second glass plate 10B that is located inside the vehicle in cross-sectional view, relative to the liquid crystal dimming film 14. The inside portion 52 includes the second glass plate 10B and the second intermediate layer 12B. The inside portion 52 may include other members other than the second glass plate 10B and the second intermediate layer 12B that are located inside the vehicle relative to the liquid crystal dimming film 14. In this embodiment, the inside portion 52 includes a heat insulating layer 18 in addition to the second glass plate 10B and the second intermediate layer 12B. The optical properties of the inside portion 52 are the overall optical properties of the inside portion 52, which is composed of multiple members.

[0083] In this embodiment, the light transmittance of the interior portion 52 at a wavelength of 400 nm is preferably 5% or less, more preferably 4% or less, and even more preferably 3% or less. This effectively suppresses the transmission of ultraviolet rays contained in the ambient light into the interior of the vehicle.

[0084] In this embodiment, the light transmittance of the interior portion 52 at a wavelength of 390 nm is preferably 90% or less, more preferably 40% or less, and even more preferably 1% or less.

[0085] In this embodiment, the light transmittance of the interior portion 52 at a wavelength of 420 nm is 90% or less, preferably 40% or less, and more preferably 5% or less.

[0086] In this embodiment, the interior portion 52 of the vehicle preferably has a light transmittance of 420 nm at twice the light transmittance of 400 nm at five times the light transmittance at four times the wavelength

[0087] Furthermore, the visible light transmittance of the interior portion 52 of the vehicle is preferably 1% to 95%, more preferably 5% to 80%, and even more preferably 10% to 50%.

[0088] Next, the optical properties of the components constituting the interior portion 52 of the vehicle will be described.

[0089] The second glass plate 10B has a light transmittance of 90% or less at 390 nm, preferably 40% or less, and more preferably 1% or less. The second glass plate 10B has a light transmittance of 93% or less at 400 nm, preferably 45% or less, and more preferably 2% or less. The second glass plate 10B has a light transmittance of 95% or less at 420 nm, preferably 45% or less, and more preferably 5% or less. The second glass plate 10B has a visible light transmittance of 40% or more, preferably 80% or more, and more preferably 90% or more.

[0090] The second intermediate layer 12B has a light transmittance of 10% or less at 390 nm, preferably 5% or less, and more preferably 1% or less. The second intermediate layer 12B has a light transmittance of 40% or less at 400 nm, preferably 10% or less, and more preferably 2% or less. The second intermediate layer 12B has a light transmittance of 93% or less at 420 nm, preferably 15% or less, and more preferably 3% or less. The second intermediate layer 12B has a visible light transmittance of 95% or less, preferably 50% or less, and more preferably 10% or less.

[0091] The heat insulating layer 18 preferably has a visible light transmittance of 35% to 94%, more preferably 35% to 93%, and even more preferably 35% to 92%.

[0092] (Laminated glass for vehicles) The overall optical properties of the laminated glass for vehicles 1 change depending on the voltage applied to the liquid crystal dimming film 14. The overall optical properties of the laminated glass for vehicles 1 will be described below by dividing them into the state in which the light transmittance of the liquid crystal dimming film 14 is lowest and the state in which the light transmittance of the liquid crystal dimming film 14 is highest. In this embodiment, the state in which the voltage applied to the liquid crystal dimming film 14 is lowest when the visible light transmittance of the liquid crystal dimming film 14 is lowest is the first state (no voltage applied). In this embodiment, the state in which the voltage applied to the liquid crystal dimming film 14 is highest when the visible light transmittance of the liquid crystal dimming film 14 is highest is the second state (rated voltage applied).

[0093] (State where the light transmittance of the liquid crystal dimming film is lowest) When the voltage applied to the liquid crystal dimming film 14 is set to the state where the visible light transmittance of the liquid crystal dimming film 14 is lowest, the overall visible light transmittance of the laminated glass for vehicles 1 is preferably 0.3% or more. When the visible light transmittance of the liquid crystal dimming film 14 is set to the state where it is lowest, the overall visible light transmittance of the laminated glass for vehicles 1 is more preferably 0.4% or more, and even more preferably 0.5% or more. Furthermore, when the visible light transmittance of the liquid crystal dimming film 14 is set to the state where it is lowest, the overall visible light transmittance of the laminated glass for vehicles 1 is preferably 5% or less, more preferably 3% or less, and even more preferably 1% or less. The visible light transmittance can be measured in accordance with the provisions of JIS R3106:2019 "Test methods for transmittance, reflectance, and emissivity of flat glass and calculation method for solar heat gain coefficient of building flat glass".

[0094] When the visible light transmittance of the liquid crystal dimming film 14 is set to its lowest state, the light transmittance of the laminated glass 1 for vehicles at a wavelength of 400 nm is preferably 5% or less, more preferably 3% or less, and even more preferably 1% or less. When the visible light transmittance of the liquid crystal dimming film 14 is set to its lowest state, the light transmittance of the laminated glass 1 for vehicles at a wavelength of 390 nm is preferably 10% or less, more preferably 5% or less, and even more preferably 1% or less. When the visible light transmittance of the liquid crystal dimming film 14 is set to its lowest state, the light transmittance of the laminated glass 1 for vehicles at a wavelength of 420 nm is preferably 30% or less, more preferably 20% or less, and even more preferably 10% or less.

[0095] (State where the light transmittance of the liquid crystal dimming film is highest) When the visible light transmittance of the liquid crystal dimming film 14 is set to the highest state, the overall visible light transmittance of the laminated glass 1 for vehicles is preferably 30% or less, more preferably 25% or less, and even more preferably 20% or less. Furthermore, when the visible light transmittance of the liquid crystal dimming film 14 is set to the highest state, the overall visible light transmittance of the laminated glass 1 for vehicles is preferably 5% or more, more preferably 10% or more, and even more preferably 15% or more.

[0096] When the visible light transmittance of the liquid crystal dimming film 14 is set to its highest state, the light transmittance of the laminated glass 1 for vehicles at a wavelength of 400 nm is preferably 5% or less, more preferably 3% or less, and even more preferably 1% or less. When the visible light transmittance of the liquid crystal dimming film 14 is set to its highest state, the light transmittance of the laminated glass 1 for vehicles at a wavelength of 390 nm is preferably 10% or less, more preferably 5% or less, and even more preferably 1% or less. When the visible light transmittance of the liquid crystal dimming film 14 is set to its highest state, the light transmittance of the laminated glass 1 for vehicles at a wavelength of 420 nm is preferably 30% or less, more preferably 20% or less, and even more preferably 10% or less.

[0097] (Effects) As described above, the laminated glass for vehicles 1 according to the first aspect of the present disclosure comprises a first glass plate 10A located on the outside of the vehicle, a second glass plate 10B located on the inside of the vehicle, a liquid crystal dimming film 14 provided between the first glass plate 10A and the second glass plate 10B and capable of changing the visible light transmittance according to the voltage applied, a first intermediate layer 12A located between the first glass plate 10A and the liquid crystal dimming film 14, and a second intermediate layer 12B located between the second glass plate 10B and the liquid crystal dimming film 14, wherein the liquid crystal dimming film 14 contains a dichroic dye, and in a cross-sectional view of the first glass plate 10A and the second glass plate 10B, the outer portion 51 located on the outside of the vehicle beyond the liquid crystal dimming film 14 has a light transmittance of 5% or less at a wavelength of 400 nm. According to this disclosure, by making the light transmittance of the exterior portion 51 at a wavelength of 400 nm 5% or less, the irradiation of ultraviolet light to the liquid crystal dimming film 14 can be effectively suppressed, thereby suppressing deterioration of the appearance of the liquid crystal dimming film 14 due to external light. Consequently, the amount of ultraviolet light transmitted through the laminated glass 1 for vehicles entering the vehicle can be reduced, and thus the irradiation of ultraviolet rays to occupants inside the vehicle can also be suppressed.

[0098] The laminated glass 1 for vehicles according to the second aspect of this disclosure is the same as the laminated glass 1 for vehicles according to the first aspect, wherein the outer portion 51 preferably has a light transmittance of 2% or less at a wavelength of 390 nm. This effectively suppresses deterioration of the appearance of the liquid crystal dimming film 14 due to external light.

[0099] The laminated glass 1 for vehicles according to the third aspect of this disclosure is the laminated glass 1 for vehicles according to the first or second aspect, wherein the first intermediate layer 12A preferably has a thickness of 0.76 mm or more. This increases the thickness of the first intermediate layer 12A constituting the outer portion 51 of the vehicle, making it easy to reduce the light transmittance of the outer portion 51 at a wavelength of 400 nm.

[0100] The laminated glass 1 for vehicles according to the fourth aspect of this disclosure is the laminated glass 1 for vehicles according to any of the first to third aspects, wherein the first glass plate 10A preferably has a thickness of 2.0 mm or more. This increases the thickness of the first glass plate 10A that constitutes the exterior portion 51 of the vehicle, thereby ensuring sufficient impact resistance of the exterior portion 51.

[0101] The laminated glass 1 for vehicles according to the fifth aspect of this disclosure is a laminated glass 1 for vehicles according to any of the first to fourth aspects, wherein, in a cross-sectional view of the first glass plate 10A and the second glass plate 10B, the interior portion 52 located on the interior side of the vehicle, relative to the liquid crystal dimming film 14, preferably has a light transmittance of 5% or less at a wavelength of 400 nm. This makes it possible to reduce the light transmittance at a wavelength of 400 nm not only in the exterior portion 51 but also in the interior portion 52. Therefore, the irradiation of ultraviolet rays to occupants inside the vehicle can be suppressed more effectively.

[0102] The laminated glass 1 for vehicles according to the sixth aspect of this disclosure is a laminated glass 1 for vehicles according to any of the first to fifth aspects, and preferably further comprises a heat insulating layer 18 provided on the in-vehicle side surface of the second glass plate 10B, having an emissivity of 0.4 or less. This suppresses the transfer of heat to the in-vehicle side.

[0103] The laminated glass 1 for vehicles according to the seventh aspect of this disclosure is a laminated glass 1 for vehicles according to any of the first to sixth aspects, and it is preferable that the total thickness of the laminated glass 1 for vehicles is 5.8 mm or more. As a result, the overall thickness of the laminated glass 1 for vehicles is increased, which makes it easy to improve the effect of suppressing the irradiation of ultraviolet light to the liquid crystal dimming film 14 and the irradiation of ultraviolet light to passengers inside the vehicle.

[0104] The laminated glass 1 for vehicles according to the eighth aspect of this disclosure is a laminated glass 1 for vehicles according to any of the first to seventh aspects, and it is preferable that the overall visible light transmittance of the laminated glass 1 for vehicles is 0.1% or more when the voltage applied to the liquid crystal dimming film 14 is set to the state in which the visible light transmittance of the liquid crystal dimming film 14 is lowest. This makes it possible to effectively suppress the intrusion of external light into the vehicle interior when the dimming state is set to a state in which the light-shielding properties of the liquid crystal dimming film 14 are high.

[0105] The laminated glass 1 for vehicles according to the ninth aspect of this disclosure is a laminated glass 1 for vehicles according to any of the first to eighth aspects, and the liquid crystal dimming film 14 preferably includes a polymer-dispersed liquid crystal or a guest-host liquid crystal. Since polymer-dispersed liquid crystals or guest-host liquid crystals are susceptible to the effects of ultraviolet light, the laminated glass 1 for vehicles according to this disclosure can reduce the effects of ambient light (especially ultraviolet light), thereby effectively suppressing the deterioration of these liquid crystals over time.

[0106] The laminated glass 1 for vehicles according to the tenth aspect of this disclosure is a laminated glass 1 for vehicles according to any of the first to ninth aspects, wherein at least one of the first intermediate layer 12A and the second intermediate layer 12B preferably includes a sound-insulating film 45 having a multilayer structure. According to this disclosure, it is possible to improve sound insulation while suppressing deterioration of the appearance of the liquid crystal dimming film 14 due to external light.

[0107] The laminated glass for vehicles 1 according to the eleventh aspect of this disclosure is a laminated glass for vehicles 1 according to any of the first to tenth aspects, wherein the first intermediate layer 12A preferably includes at least one of a resin film 42 to which an ultraviolet shielding additive 41 is added, and a multilayer film of a resin film 43 and an ultraviolet shielding film 44. According to this disclosure, the light transmittance at a wavelength of 400 nm in the first intermediate layer 12A can be effectively reduced.

[0108] The laminated glass 1 for vehicles according to the twelfth aspect of this disclosure is the laminated glass 1 for vehicles according to any of the first to eleventh aspects, wherein the outer portion 51 preferably has a light transmittance of 420 nm at a wavelength of 420 nm that is at least twice that of 400 nm at a wavelength. According to this disclosure, even when the amount of ultraviolet light transmitted, including 400 nm, is reduced, it is possible to suppress a decrease in the amount of visible light transmitted at a wavelength of 420 nm or more. Therefore, it is possible to achieve both the suppression of deterioration of the appearance of the liquid crystal dimming film 14 caused by ultraviolet light and the suppression of the influence on the color of the laminated glass 1 for vehicles.

[0109] The laminated glass 1 for vehicles according to the 13th aspect of this disclosure is the laminated glass 1 for vehicles according to any of the 1st to 12th aspects, wherein the outer portion 51 preferably has a light transmittance of 15% or more at a wavelength of 420 nm. According to this disclosure, even when the amount of ultraviolet light transmitted, including wavelength 400 nm, is reduced, the amount of visible light transmitted at wavelengths of 420 nm or more can be secured, so that deterioration of the appearance of the liquid crystal dimming film 14 caused by ultraviolet light is suppressed, and changes in the color of the laminated glass 1 for vehicles due to the reduction in ultraviolet light transmission can be suppressed.

[0110] The fourteenth aspect of this disclosure of the laminated glass for vehicles 1 is a laminated glass for vehicles 1 according to any of the first to thirteenth aspects, wherein the light transmittance of the outer portion 51 at a wavelength of 400 nm is preferably less than or equal to the light transmittance of the inner portion 52 located on the inner side of the liquid crystal dimming film 14 in a cross-sectional view of the first glass plate 10A and the second glass plate 10B at a wavelength of 400 nm. According to this disclosure, irradiation of the liquid crystal dimming film 14 with ultraviolet light can be effectively suppressed.

[0111] The laminated glass 1 for vehicles according to the 15th aspect of this disclosure is a laminated glass 1 for vehicles according to any of the 1st to 14th aspects, wherein the light transmittance of the first intermediate layer 12A at a wavelength of 400 nm is preferably less than or equal to the light transmittance of the second intermediate layer 12B at a wavelength of 400 nm. According to this disclosure, the light transmittance of the outer portion 51 at a wavelength of 400 nm can be effectively reduced.

[0112] The laminated glass 1 for vehicles according to the sixteenth aspect of this disclosure is a laminated glass 1 for vehicles according to any of the first to fifteenth aspects, wherein the surface of the first glass plate 10A is provided with a coating 60 having an ultraviolet cut function. According to this disclosure, the light transmittance of the outer portion 51 of the vehicle at a wavelength of 400 nm can be effectively reduced.

[0113] (Examples) Next, examples will be described. Table 1 shows laminated glass for vehicles in each example.

[0114] (Example 1) In Example 1, a 2.1 mm thick privacy glass (indicated as "privacy glass" in the table) was used as the first glass plate, a 0.76 mm thick UV absorber-containing transparent PVB interlayer (indicated as "30 mil high UV cut PVB" in the table) was used as the first intermediate layer, a 0.39 mm thick black dichroic dye-containing PDLC film (indicated as "black PDLC" in the table) was used as the liquid crystal dimming film, a 0.38 mm thick clear PVB interlayer (indicated as "15 mil clear PVB" in the table) was used as the second intermediate layer, and the same glass plate as the first glass plate was used as the second glass plate. These components were laminated in this order to obtain laminated glass for vehicles. In the above embodiment, a configuration in which a heat insulating layer 18 is provided on the interior side of the second glass plate 10B was illustrated, but no heat insulating layer is provided in any of the examples.

[0115] (Examples 2 to 8) In Examples 2 to 8, laminated glass for vehicles was obtained and each parameter was measured in the same manner as in Example 1, except that the components were as shown in the table. Example 2 differs from Example 1 only in the configuration of the first intermediate layer. The first intermediate layer described in Example 2 is a three-layer multilayer film in which a 0.38 mm thick clear PVB (listed as 15 ml clear PVB in the table) is used as a resin film, and a 0.038 mm thick UV absorber-containing polyester film (listed as UV cut film in the table) is used as an UV shielding film, with the UV shielding film placed between the two resin films. Example 3 differs from Example 1 only in the configuration of the second intermediate layer. The second intermediate layer described in Example 3 is the same film as the first intermediate layer (listed as 30 ml clear PVB in the table). Example 4 differs from Example 1 in the first glass plate and the first intermediate layer, but the other components are the same as in Example 1. The first glass plate described in Example 4 is the first glass plate described in Example 1 with a 10 μm thick UV shielding layer containing a benzodithiol-based UV absorber applied to the inner surface as a coating with UV-cutting function (indicated as Privacy + UVcut Coat in the table). The first intermediate layer described in Example 4 is the same film as the second intermediate layer in Example 1. Example 5 differs from Example 1 only in the composition of the first intermediate layer. The first intermediate layer described in Example 5 is the same film as the second intermediate layer in Example 1. Example 6 differs from Example 1 only in the composition of the first intermediate layer. The first intermediate layer described in Example 6 is a 0.4 mm thick UV absorber-containing EVA interlayer (indicated as 0.4 mm thick 385 nm cut interlayer in the table). Example 7 differs from Example 1 only in the composition of the first intermediate layer. The first intermediate layer described in Example 7 is a 0.76 mm thick gray-colored PVB interlayer (indicated as 30 ml colored PVB in the table). Example 8 differs from Example 1 in that the first glass plate and the first intermediate layer are different, but the other components are the same as in Example 1. The "clear glass + Ag reflective film" of the first glass plate described in Example 8 is a 130 nm thick laminated film that serves as a reflective layer on the inner surface of a 2.1 mm thick clear glass, with three functional layers containing silver and four dielectric layers of oxides mainly composed of zinc and tin alternately laminated on either side of the functional layers by sputtering. The first intermediate layer described in Example 8 is the same film as the second intermediate layer in Example 1.

[0116] The following parameters were measured or calculated for the exterior portion (laminated structure of the first glass plate and the first intermediate layer) of the obtained laminated vehicle glass. The measurement and calculation methods for each parameter were the same as those described in the embodiment. • Light transmittance (%) at a wavelength of 390 nm of the exterior portion • Light transmittance (%) at a wavelength of 400 nm of the exterior portion • Light transmittance (%) at a wavelength of 420 nm of the exterior portion • Overall visible light transmittance (%) of the laminated vehicle glass • Overall light transmittance (%) at a wavelength of 400 nm of the laminated vehicle glass • Overall light transmittance (%) at a wavelength of 420 nm of the laminated vehicle glass The light transmittance at each wavelength was measured using a UV-Vis-Near-Infrared Spectrophotometer UH4150 (manufactured by Hitachi High-tech Science Corporation). The overall light transmittance of the laminated vehicle glass is the measurement value when the light transmittance of the liquid crystal dimming film is at its lowest. Furthermore, a weather resistance test was conducted on the obtained laminated vehicle glass. In the weathering test, a xenon lamp type weathering tester (manufactured by Suga Test Instruments Co., Ltd.) was used to irradiate the first glass plate with light for 3000 hours. The above spectroscopic measuring instrument was used to measure L ＊ a ＊ b ＊ Measure the ΔE before and after light irradiation. ＊ ab was calculated. L ＊ a ＊ b ＊ is, L ＊ a ＊ b ＊ The color value in a color system, ΔE ＊ ab is L ＊ a ＊ b ＊ This is the color difference.

[0117] (Characteristics) The characteristics in Table 1 show the measurement results and calculation results for each.

[0118] In the examples 1-4, the light transmittance at a wavelength of 400 nm in the exterior portion of the vehicle was 5% or less. The lowest light transmittance at a wavelength of 400 nm was 0.3% in Examples 1 and 3. The highest light transmittance at a wavelength of 400 nm was 3.5% in Example 4. On the other hand, in the comparative examples 5-8, the light transmittance at a wavelength of 400 nm in the exterior portion of the vehicle was higher than 5% in all cases.

[0119] In the examples 1-4, the light transmittance at a wavelength of 390 nm in the exterior portion of the vehicle was 2% or less. The light transmittance at a wavelength of 390 nm was approximately the same in Examples 1-3, ranging from 0.01% to 0.02%. In Example 4, the light transmittance at a wavelength of 390 nm was 0.85%. On the other hand, in the comparative examples 5-8, the light transmittance at a wavelength of 390 nm in the exterior portion of the vehicle was higher than 2%, except for Examples 6 and 7. In Examples 1-4, the light transmittance at a wavelength of 390 nm in the exterior portion of the vehicle was 1% or less, while in Examples 5-8, the light transmittance at a wavelength of 390 nm in the exterior portion of the vehicle was higher than 1%.

[0120] In the examples 1-4, the light transmittance at a wavelength of 420 nm was 25% or more on the exterior of the vehicle. In Example 1, the light transmittance at 420 nm was 9 times or more than that at 400 nm; in Example 2, the light transmittance at 420 nm was 17 times or more than that at 400 nm; in Example 3, the light transmittance at 420 nm was 9 times or more than that at 400 nm; and in Example 4, the light transmittance at 420 nm was 7 times or more than that at 400 nm. On the other hand, in the comparative examples 5-8, the light transmittance at 420 nm was 3 times or less than that at 400 nm.

[0121] In the examples 1-4, the overall visible light transmittance of the laminated vehicle glass was 0.3% or higher when the light transmittance of the liquid crystal dimming film was at its lowest. The overall visible light transmittance was 0.92% for Example 1, 0.88% for Example 2, and 0.9% for Examples 3 and 4. In the comparative examples 5-8, the overall visible light transmittance of the laminated vehicle glass was 0.3% or higher when the light transmittance of the liquid crystal dimming film was at its lowest.

[0122] In the examples 1-4, the overall light transmittance of the laminated glass for vehicles at a wavelength of 400 nm was 1% or less when the light transmittance of the liquid crystal dimming film was at its lowest setting. The overall light transmittance at a wavelength of 400 nm was 0.02% for Example 1, 0.13% for Example 2, 0.004% for Example 3, and 0.23% for Example 4. Thus, in Examples 1-4, the overall light transmittance at a wavelength of 400 nm of the laminated glass for vehicles was 0.4% or less. In the comparative examples 5-8, the overall light transmittance at a wavelength of 400 nm of the laminated glass for vehicles at its lowest setting was greater than 1% in Examples 5 and 8. In Examples 6 and 7, it was greater than 0.4%.

[0123] In the examples 1-4, the overall light transmittance of the laminated vehicle glass at a wavelength of 420 nm was 10% or less when the light transmittance of the liquid crystal dimming film was at its lowest. The overall light transmittance at a wavelength of 420 nm was 1.06% for Example 1, 1.34% for Example 2, 0.7% for Example 3, and 0.98% for Example 4. In the comparative examples 5-8, the overall light transmittance of the laminated vehicle glass at a wavelength of 420 nm was also 10% or less when the light transmittance of the liquid crystal dimming film was at its lowest.

[0124] (Evaluation) In the evaluation, the ultraviolet (UV) transmission to the interior of the vehicle's laminated glass and the results of the weather resistance test were evaluated. For ultraviolet transmission to the interior of the vehicle, a 400nm transmittance of 1.0% or less for the entire laminated glass was marked as ○ (Good), 0.01% or less was marked as ◎ (Excellent), and greater than 1.0% was marked as × (Poor). For the weather resistance test, ΔE ＊ If ab was 10 or less, it was marked as ○ (good); if it was greater than 10, it was marked as × (bad).

[0125] As shown in Table 1, in Examples 1-4, which are examples, the evaluation for ultraviolet light transmission to the interior of the vehicle was ○ or ◎, indicating that ultraviolet light transmission to the interior of the vehicle (i.e., irradiation of occupants with ultraviolet light) can be suppressed. In the weather resistance test, in Examples 1-4, which are examples, the evaluation was ○, indicating that the deterioration of the appearance of the liquid crystal dimming film was suppressed. In Example 3, since an interlayer with ultraviolet shielding function is used in the second intermediate layer belonging to the interior part of the vehicle, the evaluation item for ultraviolet light (UV) transmission to the interior of the vehicle for the entire laminated glass for vehicles was ◎. By reducing the ultraviolet light transmittance of the interior part of the vehicle, the irradiation of occupants with ultraviolet light can be effectively suppressed. On the other hand, in Examples 5-8, which are comparative examples, the evaluation for at least the weather resistance test was ×, indicating that the deterioration of the appearance of the liquid crystal dimming film cannot be suppressed. Examples 6 and 7 show that even if the evaluation item for ultraviolet (UV) transmission to the inside of the vehicle is marked as "○", if the UV shielding function on the outside of the vehicle is insufficient, UV irradiation to the liquid crystal dimming film cannot be sufficiently reduced, and therefore the deterioration of the appearance of the liquid crystal dimming film caused by external light cannot be sufficiently suppressed.

[0126] Although embodiments of the present invention have been described above, the embodiments are not limited to those described herein. Furthermore, the aforementioned components include those that can be easily conceived by those skilled in the art, those that are substantially the same, and those that fall within the so-called equivalent range. Moreover, the aforementioned components can be combined as appropriate. Furthermore, various omissions, substitutions, or modifications of the components can be made without departing from the spirit of the embodiments described above.

[0127] 1 Laminated glass for vehicles 10A First glass plate 10B Second glass plate 12 Intermediate layer 12A First intermediate layer 12B Second intermediate layer 14 Liquid crystal dimming film 18 Heat insulating layer 41 UV shielding additive 42 Resin film 43 Resin film 44 UV shielding film 45 Sound insulation film 51 Outer part of vehicle 52 Inner part of vehicle 60 Coating having UV cut function The entire contents of the specification, claims, drawings and abstract of Japanese Patent Application No. 2025-039183, filed on March 12, 2025, are incorporated herein by reference as disclosure of the specification of the present invention.

Claims

1. Laminated glass for vehicles comprising: a first glass plate located on the outside of the vehicle; a second glass plate located on the inside of the vehicle; a liquid crystal dimming film provided between the first glass plate and the second glass plate, capable of changing the visible light transmittance according to the applied voltage; a first intermediate layer located between the first glass plate and the liquid crystal dimming film; and a second intermediate layer located between the second glass plate and the liquid crystal dimming film, wherein the liquid crystal dimming film contains a dichroic dye, and in a cross-sectional view of the first glass plate and the second glass plate, the outer portion located on the outside of the vehicle beyond the liquid crystal dimming film has a light transmittance of 5% or less at a wavelength of 400 nm.

2. The vehicle laminated glass according to claim 1, wherein the outer portion of the vehicle has a light transmittance of 2% or less at a wavelength of 390 nm.

3. The laminated glass for vehicles according to claim 1, wherein the first intermediate layer has a thickness of 0.76 mm or more.

4. The first glass plate has a thickness of 2.0 mm or more, as described in claim 1, for use in vehicles.

5. The laminated glass for vehicles according to claim 1, wherein, in a cross-sectional view of the first glass plate and the second glass plate, the portion on the interior side that is located on the interior side of the vehicle than the liquid crystal dimming film has a light transmittance of 5% or less at a wavelength of 400 nm.

6. The laminated glass for vehicles according to claim 1, further comprising a heat insulating layer provided on the in-vehicle side surface of the second glass plate, having an emissivity of 0.4 or less.

7. The laminated glass for vehicles according to claim 1, wherein the total thickness of the laminated glass for vehicles is 5.8 mm or more.

8. The laminated glass for vehicles according to claim 1, wherein when the voltage applied to the liquid crystal dimming film is set to the state in which the visible light transmittance of the liquid crystal dimming film is lowest, the overall visible light transmittance of the laminated glass for vehicles is 0.3% or more.

9. The laminated glass for vehicles according to claim 1, wherein the liquid crystal dimming film includes a polymer-dispersed liquid crystal or a guest-host liquid crystal.

10. The laminated glass for vehicles according to claim 1, wherein at least one of the first intermediate layer and the second intermediate layer includes a sound-insulating film having a multilayer structure.

11. The laminated glass for vehicles according to claim 1, wherein the first intermediate layer comprises at least one of a resin film to which an ultraviolet shielding additive has been added, and a multilayer film of a resin film and an ultraviolet shielding film.

12. The vehicle laminated glass according to claim 1, wherein the outer portion of the vehicle has a light transmittance at a wavelength of 420 nm that is at least twice that of a light transmittance at a wavelength of 400 nm.

13. The vehicle-mounted portion has a light transmittance of 15% or more at a wavelength of 420 nm, as described in claim 1.

14. The light transmittance at a wavelength of 400 nm of the outer portion of the vehicle is less than or equal to the light transmittance at a wavelength of 400 nm of the inner portion of the first glass plate and the second glass plate, which is located on the inner side of the vehicle than the liquid crystal dimming film, as described in claim 1.

15. The laminated glass for vehicles according to claim 1, wherein the light transmittance of the first intermediate layer at a wavelength of 400 nm is less than or equal to the light transmittance of the second intermediate layer at a wavelength of 400 nm.

16. The laminated glass for vehicles according to claim 1, wherein the surface of the first glass plate is provided with a coating that has an ultraviolet-cutting function.

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