Laminated glass, laminated glass for vehicle, and laminated glass for vehicle roof

Abstract

To provide a laminated glass capable of suppressing reflection of interior trim, etc. even when in a light-shielding state. A laminated glass (10) according to one embodiment of the present invention has a first glass plate (11), a first interlayer film (12), a PDLC dimming film (13), a second interlayer film (14), and a second glass plate (15) in this order. The laminated glass (10) has a total light transmittance of 10% or less and a haze value of 50% or more when the PDLC dimming film (13) is turned off. The second glass plate (15) has a low-emissivity film (16) on the surface of the side opposite the second interlayer film (14) side, and the low-emissivity film (16) has visible light reflectance of from 0.2% to 3.8% on the surface of the side opposite the second glass plate (15) side.

Description

Laminated glass, laminated glass for vehicles, and laminated glass for vehicle roofs

[0001] The present invention relates to laminated glass, laminated glass for vehicles, and laminated glass for vehicle roofs.

[0002] It is known that forming a low-emissivity film on the window glass of automobiles, buildings, ships, etc. suppresses heat transfer through the window glass. Suppressing heat transfer through the window glass can improve the comfort of passengers and occupants inside automobiles, buildings, ships, etc. Laminated glass with a low-emissivity film formed on the interior surface can suppress the re-radiation of heat from outside, such as sunlight, and also suppress the outflow of heat emitted by people inside the room, thereby suppressing heat transfer between the inside and outside through the glass.

[0003] Patent Document 1 discloses a technique for forming a low-emission film on the indoor side of a substrate.

[0004] Special table 2015-512854 publication

[0005] In recent years, technologies have been developed for using laminated glass with a light-controlling function as window glass for buildings, vehicles, etc. Such laminated glass with a light-controlling function can be constructed by providing a light-controlling film on the laminated glass. For example, a PDLC-type light-controlling film may be used as the light-controlling film for laminated glass. In such laminated glass, forming a low-emissivity film on the indoor-side surface of the glass can improve indoor comfort and ensure privacy.

[0006] However, when laminated glass with a low-emissivity coating is used, the amount of light coming from outside is reduced when the light control film is used to block out the light from outside, which causes the problem of interior decoration and other items being reflected prominently on the laminated glass.

[0007] Furthermore, when a PDLC light control film is used as a light control film for laminated glass, the operating principle of the PDLC light control film can cause a grainy appearance when the laminated glass is viewed from the inside. If the grainy appearance becomes pronounced, it can cause a unique unpleasant feeling (haze discomfort).

[0008] In view of the above problems, an object of the present invention is to provide laminated glass, laminated glass for vehicles, and laminated glass for vehicle roofs that can suppress reflection of interior interiors and the like and suppress unpleasant haze even when light is blocked.

[0009] A glass plate for a vehicle, a laminated glass for a vehicle, and a laminated glass for a vehicle roof according to one aspect of the present disclosure have the following configuration.

[0010] [1] A laminated glass having, in this order, a first glass plate, a first interlayer film, a PDLC-type light control film, a second interlayer film, and a second glass plate, wherein the laminated glass has a total light transmittance of 10% or less and a haze value of 50% or more when the PDLC-type light control film is turned off, the second glass plate has a low-emissivity film on a surface opposite to the second interlayer film side, and the low-emissivity film has a visible light reflectance of 0.2% or more and 3.8% or less on the surface opposite to the second glass plate side.

[0011] [2] The laminated glass according to [1], wherein the low-emissivity film has, in this order from the second glass plate side, a transparent conductive layer and a reflection adjustment layer, and the ratio of the thickness of the reflection adjustment layer to the thickness of the transparent conductive layer is 0.47 or more and 0.70 or less.

[0012] [3] A laminated glass having, in this order, a first glass plate, a first interlayer film, a PDLC-type light control film, a second interlayer film, and a second glass plate, wherein the laminated glass has a total light transmittance of 10% or less and a haze value of 50% or more when the PDLC-type light control film is turned off, the second glass plate has a low-emissivity film on a surface opposite to the second interlayer film side, the low-emissivity film has, in this order from the second glass plate side, a transparent conductive layer and a reflection adjustment layer, and the ratio of the film thickness of the reflection adjustment layer to the film thickness of the transparent conductive layer is 0.47 or more and 0.70 or less.

[0013] [4] The laminated glass according to [3], wherein the low-emissivity film has a visible light reflectance of 0.2% or more and 3.8% or less on the surface opposite to the second glass plate.

[0014] [5] The laminated glass according to any one of [2] to [4], wherein the transparent conductive layer has a film thickness of 80 nm or more and 160 nm or less.

[0015] [6] The laminated glass according to any one of [2] to [5], wherein the transparent conductive layer is an ITO layer, a tin oxide layer, a fluorine-doped tin oxide layer, an antimony-doped tin oxide layer, a silver layer, a zirconium nitride layer, or a titanium nitride layer.

[0016] [7] The laminated glass according to any one of [2] to [6], wherein the reflection adjustment layer contains an oxide or oxynitride of at least one metal selected from the group consisting of Ti, Nb, Ta, Zn, Al, In, Si, and Zr.

[0017] [8] The laminated glass according to any one of [2] to [7], wherein the reflection adjustment layer has a film thickness of 50 nm or more and 100 nm or less.

[0018] [9] The laminated glass according to any one of [2] to [8], wherein the low-emissivity film further has a color correction layer, the color correction layer being composed of a plurality of layers including, in order from the second glass plate side, a first layer and a second layer, and the refractive index of the first layer for light with a wavelength of 630 nm is higher than the refractive index of the second layer for light with a wavelength of 630 nm.

[0019]

[10] The laminated glass according to [9], wherein the first layer has a refractive index of 1.7 or more and 2.5 or less for light with a wavelength of 630 nm, and the second layer has a refractive index of 1.6 or less for light with a wavelength of 630 nm.

[0020]

[11] The laminated glass according to any one of [2] to

[10] , wherein the low-emissivity film further has a color correction layer, and the color correction layer contains an oxide or oxynitride of at least one metal selected from the group consisting of Ti, Nb, Ta, Zn, Al, In, Si, and Zr.

[0021]

[12] The laminated glass according to any one of [2] to

[11] , wherein the low-emissivity film has a color correction layer between the surface of the second glass plate facing the low-emissivity film and the transparent conductive layer, and the color correction layer has a film thickness of 20 nm or more and 60 nm or less.

[0022]

[13] The laminated glass according to any one of [1] to

[12] , wherein the low-emissivity film has an emissivity of 0.3 or less on the surface opposite to the second glass plate.

[0023]

[14] The laminated glass according to any one of [2] to

[13] , wherein the low-emissivity film has an adhesion-improving layer disposed between the transparent conductive layer and the reflection-adjusting layer.

[0024]

[15] A laminated glass for vehicles, comprising the laminated glass according to any one of [1] to

[14] .

[0025]

[16] A laminated glass for a vehicle roof, comprising the laminated glass according to any one of [1] to

[14] .

[0026] The present invention can provide laminated glass, laminated glass for vehicles, and laminated glass for vehicle roofs that can suppress reflections of interior interiors and the like and suppress unpleasant haze even when light is blocked.

[0027] Fig. 1 is a cross-sectional view showing an example of the configuration of laminated glass according to an embodiment; Fig. 2 is a cross-sectional view showing an example of a low-emissivity film included in laminated glass according to an embodiment; Fig. 3 is a cross-sectional view showing a modified example of a low-emissivity film included in laminated glass according to an embodiment; Fig. 4 is a cross-sectional view showing a modified example of a low-emissivity film included in laminated glass according to an embodiment.

[0028] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. Fig. 1 is a cross-sectional view showing an example of the configuration of laminated glass according to this embodiment. As shown in Fig. 1, laminated glass 10 according to this embodiment includes, in this order, a first glass plate 11, a first interlayer film 12, a PDLC light control film 13, a second interlayer film 14, a second glass plate 15, and a low-emissivity film 16.

[0029] The laminated glass 10 according to this embodiment is applied to window glass in automobiles, buildings, ships, and the like, for example. The laminated glass 10 is suitable for vehicle laminated glass. From the viewpoint of excellent heat insulation, the laminated glass 10 is particularly suitable for vehicle roof laminated glass, etc. Vehicle roof laminated glass is used in the roof of a vehicle. The laminated glass 10 is installed so that the surface on the first glass sheet 11 side faces the vehicle exterior or exterior, and the surface on the low-emissivity film 16 side faces the vehicle interior or interior. Hereinafter, "vehicle exterior or exterior" may be simply referred to as "exterior". Furthermore, "vehicle interior or interior" may be simply referred to as "interior".

[0030] The PDLC light control film 13 is a light control film using polymer dispersed liquid crystal (PDLC). The PDLC light control film 13 has a light control function in which its transmittance changes depending on the applied voltage. By adjusting the applied voltage to the PDLC light control film 13, the transmittance of visible light and near-infrared light through the laminated glass 10 can be reversibly controlled. By reducing the visible light and near-infrared light transmittance of the laminated glass 10, heat rays can be blocked from the outside into the room, suppressing an increase in the room temperature. Furthermore, by reducing the visible light transmittance of the laminated glass 10, visible light can be blocked from the inside into the outside, making it difficult to see inside the room from the outside. Therefore, the laminated glass 10 can adjust the indoor environment and ensure privacy.

[0031] The laminated glass 10 according to this embodiment has a total light transmittance of 10% or less and a haze value of 50% or more when the PDLC light control film 13 is turned off. Here, "turning off the PDLC light control film 13" means minimizing the parallel light transmittance of the laminated glass 10 by adjusting the voltage applied to the PDLC light control film 13. In other words, "turning off the PDLC light control film 13" means blocking light that passes through the laminated glass 10. When the PDLC light control film 13 is turned off, the haze value of the laminated glass 10 is maximized.

[0032] The total light transmittance of the laminated glass 10 when the PDLC light control film 13 is turned off is preferably low, i.e., closer to 0%. From the viewpoint of adjusting the indoor environment and ensuring privacy, the total light transmittance of the laminated glass 10 when the PDLC light control film 13 is turned off is preferably 10% or less, more preferably 8% or less, even more preferably 6% or less, even more preferably 5% or less, particularly preferably 3% or less, particularly more preferably 2% or less, extremely preferably 1% or less, more extremely preferably 0.5% or less, even extremely preferably 0.3% or less, particularly extremely preferably 0.1% or less, and particularly extremely extremely preferably 0.05% or less. If it is desired to be able to see the scenery outside the vehicle from inside the vehicle, the total light transmittance of the laminated glass 10 when the PDLC light control film 13 is turned off may be 0.01% or more. From the viewpoint of ensuring privacy, the haze value of the laminated glass 10 when the PDLC light control film 13 is turned off is preferably 50% or more, more preferably 60% or more, even more preferably 70% or more, particularly preferably 80% or more, particularly more preferably 85% or more, extremely preferably 90% or more, and particularly extremely preferably 95% or more. The total light transmittance is a value measured with a spectrophotometer. The haze value is a value measured with a haze meter. The total light transmittance and haze value of the laminated glass 10 may be measured in a laboratory, or may be measured while the glass is installed in a vehicle or the like.

[0033] The types of the first glass plate 11 and the second glass plate 15 are not particularly limited. The first glass plate 11 and the second glass plate 15 may be, for example, soda-lime glass, quartz glass, borosilicate glass, or alkali-free glass. From the viewpoint of ease of bending, the first glass plate 11 and the second glass plate 15 are preferably soda-lime glass.

[0034] The first glass plate 11 and the second glass plate 15 may be colorless or colored. The thickness of the first glass plate 11 and the second glass plate 15 is preferably 0.5 mm or more, more preferably 0.8 mm or more, even more preferably 1.0 mm or more, particularly preferably 1.3 mm or more, and particularly preferably 1.6 mm or more. The thickness of the first glass plate 11 and the second glass plate 15 is preferably 5.0 mm or less, more preferably 4.5 mm or less, even more preferably 4.0 mm or less, particularly preferably 3.5 mm or less, and particularly preferably 3.2 mm or less. The thicknesses of the first glass plate 11 and the second glass plate 15 may be the same or different. The first glass plate 11 and the second glass plate 15 may be ultraviolet-cutting glass plates capable of blocking ultraviolet rays. The ultraviolet-cutting glass plate is a glass plate with reduced ultraviolet transmittance, and may be, for example, borosilicate glass containing a copper compound. Here, the copper compound is, for example, cuprous oxide.

[0035] The first interlayer film 12 and the second interlayer film 14 are preferably made of, for example, a transparent resin. Examples of resins that make up the first interlayer film 12 and the second interlayer film 14 include polyvinyl butyral (PVB), polyvinyl chloride, ethylene vinyl acetate (EVA), cycloolefin polymer, urethane resin, and polyvinylidene fluoride (PVDF). The film thickness of the first interlayer film 12 and the second interlayer film 14 is preferably 0.1 mm or more, more preferably 0.2 mm or more, and even more preferably 0.3 mm or more. The film thickness of the first interlayer film 12 and the second interlayer film 14 is preferably 2.0 mm or less, more preferably 1.0 mm or less, and even more preferably 0.7 mm or less. The first interlayer film 12 and the second interlayer film 14 may be colorless or colored. The first interlayer film 12 and the second interlayer film 14 may be colored, for example, by being made of a resin containing a colorant such as a pigment.

[0036] The low-emissivity film 16 has a visible light reflectance of 3.8% or less on the surface opposite the second glass plate 15 (the surface facing the interior). Therefore, even when the PDLC light control film 13 is turned off, that is, when the amount of light transmitted from the first glass plate 11 is small, the absolute amount of reflected visible light in the laminated glass 10 is reduced. This makes it possible to reduce the reflection of interior interior decorations and the like on the laminated glass 10 when viewing the first glass plate 11 from the low-emissivity film 16 side. In other words, it makes it possible to reduce the reflection of interior interior decorations and the like on the laminated glass 10 when viewing the laminated glass 10 from the interior side. From the viewpoint of sufficiently suppressing reflections of interior interiors, etc., the visible light reflectance on the indoor surface of the low-emissivity film 16 is preferably 3.6% or less, more preferably 3.5% or less, even more preferably 3.3% or less, particularly preferably 3.0% or less, particularly more preferably 2.8% or less, extremely preferably 2.5% or less, more extremely preferably 2.3% or less, even extremely preferably 2.0% or less, particularly extremely preferably 1.8% or less, and particularly extremely preferably 1.5% or less. Furthermore, from the viewpoint of suppressing unpleasant haze, the visible light reflectance on the indoor surface of the low-emissivity film 16 is preferably 0.2% or more, more preferably 0.5% or more, even more preferably 0.8% or more, and particularly preferably 1.0% or more. The visible light reflectance is a value measured by a measurement method conforming to JIS R3106.

[0037] Due to the operating principle of the PDLC light control film 13, the laminated glass 10 may have a grainy appearance when viewed from the low-emissivity film side. If the graininess becomes too pronounced, people inside the room may feel uncomfortable. Hereinafter, the discomfort caused by the pronounced graininess will be referred to as "haze discomfort." From the viewpoint of suppressing haze discomfort, the visible light reflectance of the low-emissivity film 16 on the surface opposite the second glass plate 15 is preferably 0.2% or more, and more preferably 1.0% or more.

[0038] The laminated glass 10 may absorb heat due to light from outside, such as sunlight. The low-emissivity film 16 prevents the heat absorbed by the laminated glass 10 from being re-radiated into the room, thereby preventing an increase in indoor temperature, such as in summer. The low-emissivity film 16 also prevents a decrease in indoor temperature, such as in winter, by preventing heat diffusion from the room to the outside. In this way, the low-emissivity film 16 has an environmental adjustment function that adjusts the indoor environment. The emissivity of the low-emissivity film 16 on the surface opposite the second glass sheet 15 is preferably 0.3 or less, from the viewpoint of fully exerting its environmental adjustment function. The emissivity is a value measured using a measurement method in accordance with JIS R1801.

[0039] The low-emissivity film 16 may include, for example, a transparent conductive layer 21, a reflection adjustment layer 22, and other layers. In the present embodiment, a case will be described in which the low-emissivity film 16 includes the transparent conductive layer 21 and the reflection adjustment layer 22. FIG. 2 is a cross-sectional view showing an example of the low-emissivity film included in the laminated glass 10 according to the first embodiment. The low-emissivity film 16 included in the laminated glass 10 according to the present embodiment includes, in order from the second glass plate 15 side, the transparent conductive layer 21 and the reflection adjustment layer 22.

[0040] The transparent conductive layer 21 is preferably an ITO (indium tin oxide) layer, a tin oxide layer, a fluorine-doped tin oxide layer, an antimony-doped tin oxide layer, a silver layer, a zirconium nitride layer, or a titanium nitride layer. The transparent conductive layer 21 may contain an additive. When the transparent conductive layer 21 is an ITO layer, the additive may be, for example, Ga, Zn, Al, and / or Nb. When the transparent conductive layer 21 is an ITO layer, the proportion of tin oxide contained in the ITO layer is preferably 5% by mass or more and 12.5% ​​by mass or less, and more preferably 6.5% by mass or more and 11% by mass or less, from the viewpoint of reducing resistance. Furthermore, the ITO layer may contain less than 50% by mass of other materials in addition to ITO. The other materials contained in the ITO layer may be, for example, sodium, lead, and / or iron.

[0041] From the viewpoint of exhibiting sufficient low-emission performance and obtaining necessary heat insulating performance, the film thickness of the transparent conductive layer 21 is preferably 80 nm or more, more preferably 85 nm or more, particularly preferably 90 nm or more, particularly more preferably 95 nm or more, and extremely preferably 100 nm or more. From the viewpoint of improving productivity, the film thickness of the transparent conductive layer 21 is preferably 160 nm or less, more preferably 155 nm or less, and particularly preferably 150 nm or less. The refractive index of the transparent conductive layer 21 with respect to light having a wavelength of 630 nm is preferably 1.7 or more and 1.8 or less.

[0042] The reflection adjustment layer 22 preferably contains an oxide or oxynitride of at least one metal selected from the group consisting of Ti, Nb, Ta, Zn, Al, In, Si, and Zr, and more preferably contains an oxide of Si. The thickness of the reflection adjustment layer 22 is preferably 50 nm or more and 100 nm or less from the viewpoint of reducing the reflectance of light in the visible light region. The thickness of the reflection adjustment layer 22 is more preferably 55 nm or more, and particularly preferably 60 nm or more. The thickness of the reflection adjustment layer 22 is more preferably 95 nm, particularly preferably 90 nm or less, particularly more preferably 85 nm or less, and extremely preferably 80 nm or less. The refractive index of the reflection adjustment layer 22 for light with a wavelength of 630 nm is preferably 1.7 or less, and more preferably 1.55 or less, from the viewpoint of exhibiting sufficient low emissivity.

[0043] The ratio of the thickness of transparent conductive layer 21 to the thickness of reflection adjustment layer 22 is preferably 0.47 or more and 0.70 or less, from the viewpoint of reducing the reflectance of light in the visible light region and reducing the emissivity. The ratio of the thickness of transparent conductive layer 21 to the thickness of reflection adjustment layer 22 is more preferably 0.48 or more, particularly preferably 0.49 or more, and particularly more preferably 0.50 or more. The ratio of the thickness of transparent conductive layer 21 to the thickness of reflection adjustment layer 22 is more preferably 0.68 or less, particularly preferably 0.65 or less, particularly more preferably 0.63 or less, and extremely preferably 0.60 or less.

[0044] The low-emissivity film 16 shown in Figure 2 is an example, and in this embodiment, the low-emissivity film 16 may have other configurations. Modified examples of the low-emissivity film 16 will be described below with reference to Figures 3 and 4. Figures 3 and 4 are cross-sectional views showing modified examples of the low-emissivity film included in the laminated glass according to the embodiment.

[0045] The low-emissivity film 17 shown in FIG. 3 further includes a color correction layer 23. The color correction layer 23 is provided, for example, between the second glass plate 15 and the transparent conductive layer 21. The color correction layer 23 may contain an oxide or oxynitride of at least one metal selected from the group consisting of Ti, Nb, Ta, Zn, Al, In, Si, and Zr. From the viewpoint of reducing the angle dependence of reflected light, the film thickness of the color correction layer 23 is preferably 20 nm or more, more preferably 25 nm or more, and particularly preferably 30 nm or more. From the viewpoint of reducing the angle dependence of reflected light, the film thickness of the color correction layer 23 is preferably 60 nm or less, more preferably 55 nm or less, and particularly preferably 50 nm or less.

[0046] The color correction layer 23 may be composed of multiple layers including, in order from the second glass plate 15 side, a first layer and a second layer. The refractive index of the first layer for light with a wavelength of 630 nm is higher than the refractive index of the second layer for light with a wavelength of 630 nm. The refractive index of the first layer for light with a wavelength of 630 nm is preferably 1.7 or more and 2.5 or less, more preferably 1.8 or more and 2.3 or less, and particularly preferably 1.8 or more and 2.2 or less. The refractive index of the second layer for light with a wavelength of 630 nm is preferably 1.6 or less, more preferably 1.55 or less.

[0047] The first layer preferably contains an oxide or oxynitride of at least one metal selected from the group consisting of Ti, Nb, Ta, Zn, Al, In, Si, and Zr. The first layer preferably contains ZrO doped with 0.1% by mass to 10% by mass of Si. ２ The thickness of the first layer is preferably 3 nm or more, more preferably 5 nm or more, particularly preferably 7 nm or more, and particularly more preferably 9 nm or more. The thickness of the first layer is preferably 40 nm or less, more preferably 35 nm or less, even more preferably 30 nm or less, particularly preferably 25 nm or less, particularly more preferably 23 nm or less, extremely preferably 20 nm or less, more extremely preferably 18 nm or less, even extremely preferably 17 nm or less, and particularly extremely preferably 15 nm or less.

[0048] The second layer is SiO ２ , SiON, or MgF ２It is preferable that the material is mainly composed of SiO ２ The second layer preferably has a thickness of 5 nm or more, more preferably 10 nm or more. The second layer preferably has a thickness of 50 nm or less, more preferably 45 nm or less.

[0049] The low-emissivity film 18 shown in Fig. 4 further includes an adhesion improving layer 24. The adhesion improving layer 24 is provided between the transparent conductive layer 21 and the reflection adjustment layer 22. The adhesion improving layer 24 is preferably made of a metal oxide such as tin oxide, zinc oxide, or cerium oxide. The thickness of the adhesion improving layer 24 is preferably 1 nm or more and 10 nm or less.

[0050] The laminated glass 10 shown in FIG. 1 is an example, and the laminated glass 10 in this embodiment may have other configurations. For example, the laminated glass 10 may be provided with a self-cleaning film on the surface of the first glass sheet 11 opposite the first interlayer film 12 side. Dirt adhering to the surface of the self-cleaning film is more easily removed by contact with moisture such as rainwater than dirt adhering to a glass surface not provided with a self-cleaning film. The self-cleaning film may be made of, for example, a titania-based material, a silica-based material, or a siloxane-based material. The film thickness of the self-cleaning film is, for example, 5 nm to 50 nm, preferably 10 nm to 40 nm, and more preferably 15 nm to 35 nm.

[0051] The laminated glass 10 may also include an infrared reflective film between the first glass plate 11 and the PDLC light control film 13. The infrared reflective film may be provided between the first glass plate 11 and the first interlayer film 12, or may be provided within the first interlayer film 12. The infrared reflective film selectively reflects infrared rays to suppress a rise in temperature inside the room and to suppress thermal degradation of the first interlayer film 12, the second interlayer film 14, and the like. The infrared reflective film may be composed of multiple layers. For example, the infrared reflective film may be configured such that at least one of the multiple layers contains an infrared reflective material. The infrared reflective material is a material that reflects infrared rays, and may be, for example, silver (Ag), transparent conductive oxides such as indium tin oxide and zinc oxide, fluorine-doped tin oxide, or any other suitable material that blocks a significant amount of infrared radiation. The infrared reflective film may be configured, for example, to include a layer containing a dielectric (dielectric layer) and a layer containing Ag (Ag layer). The derivative may be, for example, silicon nitride, titanium oxide, silicon oxynitride, tin oxide, other types of metal (alloy) oxides, or other types of metal (alloy) nitrides. Examples of other types of metal oxides include zinc tin oxide, aluminum zinc oxide, nickel chromium oxide, silver oxide, and zinc oxide. The infrared reflective film may have a configuration in which an Ag layer is sandwiched between at least a pair of dielectric layers. The infrared reflective film may also include multiple Ag layers. From the viewpoint of exhibiting sufficient infrared reflective performance and reducing manufacturing costs, the infrared reflective film preferably includes two or three Ag layers. When the infrared reflective film includes two Ag layers, it is preferable that the infrared reflective film include, from the first glass plate 11 side, multiple dielectric layers, an Ag layer, multiple dielectric layers, an Ag layer, and multiple dielectric layers. When the infrared reflective film includes three Ag layers, it is preferable that the infrared reflective film includes, from the first glass plate 11 side, a plurality of dielectric layers, an Ag layer, a plurality of dielectric layers, an Ag layer, a plurality of dielectric layers, an Ag layer, and a plurality of dielectric layers. The plurality of dielectric layers are layers containing different derivatives or different composition ratios of the derivatives. When the infrared reflective film includes two Ag layers, the film thickness is preferably 500 nm or less, more preferably 400 nm or less, particularly preferably 300 nm or less, and particularly more preferably 250 nm or less.When the infrared reflective film contains two Ag layers, the film thickness is preferably 50 nm or more, more preferably 100 nm or more, and particularly preferably 150 nm or more. When the infrared reflective film contains three Ag layers, the film thickness is preferably 600 nm or less, more preferably 500 nm or less, particularly preferably 400 nm or less, and particularly more preferably 350 nm or less. When the infrared reflective film contains three Ag layers, the film thickness is preferably 100 nm or more, more preferably 150 nm or more, particularly preferably 200 nm or more, and particularly more preferably 250 nm or more.

[0052] Next, examples of the present invention will be described. As samples according to the examples, laminated glass samples were prepared by the following method. Any of the following glass plates was used.

[0053] <VFL> Green glass manufactured by AGC. The plate thickness of the VFL was 2.0 mm. The total light transmittance of the VFL was 86%.

[0054] <FL> Clear glass manufactured by AGC The plate thickness of the FL was 2.0 mm. The total light transmittance of the FL was 91%.

[0055] <DGL> Privacy glass manufactured by AGC. The DGL had a thickness of 2.0 mm and a total light transmittance of 38%.

[0056] A first layer of the color tone correction layer was formed on one surface of one glass plate (second glass plate). In Examples 1 to 21, the first layer was a ZrO ２ In Examples 22 to 24, a Ta layer (Si content 5 mass %: ZSO) (refractive index at wavelength 630 nm = 2.12) was formed as the first layer. ２ O ５ In Examples 25 to 28, a TiO layer was formed as the first layer. ２ A layer was deposited.

[0057] Next, a second layer of the color tone correction layer, SiO 2 , was deposited on the first layer of the color tone correction layer by sputtering. ２ A layer was deposited.

[0058] Next, an ITO layer was formed as a transparent conductive layer on the color tone correction layer by sputtering. Note that the second glass plate was not heated during the film formation. As a result, an amorphous ITO layer was obtained.

[0059] Next, a SiO 2 film was formed as a reflection adjustment layer on the ITO layer by sputtering. ２ A layer was deposited.

[0060] The second glass plate was then heated at 650° C. for 7 minutes.

[0061] Next, a laminate was formed by laminating a first glass plate, a first interlayer film, a PDLC-type light control film, a second interlayer film, and a second glass plate in this order. TGCNYO FOGLEAR GREY type (manufactured by CloudPoint Co., Ltd.) was used as the PDLC-type light control film. The first interlayer film and the second interlayer film were either of the following:

[0062] <Clear> Sekisui Chemical S-LEC ＴＭ Regular interlayer

[0063] <Gray (2%)> Sekisui Chemical S-LEC ＴＭ 7002

[0064] <Gray (5%)> Sekisui Chemical S-LEC ＴＭ 7005

[0065] <Gray (8%)> Sekisui Chemical S-LEC ＴＭ 7008

[0066] <Gray (18%)> Sekisui Chemical S-LEC ＴＭ 7018

[0067] The laminated body was heated to 135°C and pressed to obtain laminated glass samples according to Examples 1 to 28. Examples 1 to 3 are comparative examples, and Examples 4 to 28 are working examples. The combinations of the first and second glass plates and the first and second interlayer films used in the samples according to Examples 1 to 28 are shown in Table 1 below.

[0068]

[0069] The thickness of each layer in the low-emissivity coating of the samples according to Examples 1 to 28 is shown in Table 2 below.

[0070]

[0071] Measurements and sensitivity tests were carried out to evaluate the samples thus prepared.

[0072] <Measurement> The total light transmittance was measured using a measurement method in accordance with JIS K7136 when the PDLC light control film was turned off. A haze meter HZ-V3 was used to measure the total light transmittance. The visible light reflectance was measured on the surface of the laminated glass facing the low-emissivity film using a measurement method in accordance with JIS R3106. A spectrophotometer U-4100 (manufactured by Hitachi High-Technologies Corporation) was used to measure the visible light reflectance. The haze value was measured using a measurement method in accordance with JIS K7136 when the PDLC light control film was turned off. The emissivity was measured on the surface of the laminated glass facing the low-emissivity film using a measurement method in accordance with JIS R1801. A Fourier transform infrared spectrophotometer IRPrestige-21 (manufactured by Shimadzu Corporation) was used to measure the emissivity. A haze meter HZ-V3 (manufactured by Suga Test Instruments) was used to measure the haze value.

[0073] <Sensitivity test> With the PDLC light control film turned off, the sense of discomfort caused by haze when the laminated glass was viewed from the indoor side was evaluated on the following 5-point scale: 1: Not uncomfortable (no graininess can be recognized) 2: Not uncomfortable (graininess can be recognized) 3: Not uncomfortable (graininess can be clearly recognized) 4: Not uncomfortable, but there is a sense of incongruity 5: Feels uncomfortable

[0074] With the PDLC light-control film turned off, the reflection of the interior of the room on the laminated glass when looking at the laminated glass from inside the room was evaluated using the following five-point scale: 1: Not visible 2: Something is visible 3: The interior can be seen if careful 4: The interior can be seen normally 5: The interior can be seen clearly

[0075] With the PDLC light control film turned off, glare when looking from the indoor side to the outdoor side was evaluated using the following three-point scale: 1: No glare even when looking directly at the sun 2: Glare when looking directly at the sun, but tolerable glare 3: Cannot look directly at the sun, glare tolerable

[0076] Table 3 below shows the measurement results and sensitivity test results for the samples according to Examples 1 to 28.

[0077]

[0078] The visible light reflectance of the laminated glass varies depending on the combination of the film thicknesses of the first color correction layer, the second color correction layer, the transparent conductive layer, and the reflection adjustment layer. The total light transmittance of the laminated glass when the PDLC light control film is turned off varies depending on the materials constituting the glass plates and interlayer. As shown in Table 3, for the samples of Examples 4 to 28, when the PDLC light control film was turned off, the total light transmittance of the laminated glass was 5.8% or less, the visible light reflectance was 0.2% to 3.5%, and the haze value was 50% or more. For the samples of Examples 4 to 28, the haze discomfort was 4 or less, which was good. For the samples of Examples 4 to 28, the glare was 4 or less, which was good. For the samples of Examples 4 to 28, the glare was 2 or less, which was good.

[0079] Comparison of the samples in Examples 1 to 4 revealed that unpleasant haze can be suppressed when the total light transmittance of the laminated glass when the PDLC light-control film is turned off is 5.8% or less and the visible light reflectance is 0.2% or more. When the visible light reflectance is 0.2% or less, i.e., too low, the effect of reflected light is small when viewing the surface on the low-emissivity film 16 side from inside the vehicle or room, and the graininess that fundamentally occurs in the PDLC light-control film is visible as is, making unpleasant haze more likely to occur. When the visible light reflectance is 0.2% or more, i.e., when moderately reflected light is present, the graininess of the PDLC light-control film can be adequately shielded, thereby suppressing unpleasant haze. Comparison of the samples in Examples 16 to 19 and 21 confirmed that lowering the visible light reflectance can further suppress glare. Comparison of the samples in Examples 3 and 16 confirmed that lowering the total light transmittance of the laminated glass when the PDLC light-control film is turned off can further suppress glare.

[0080] The present invention has been described above in accordance with the above-mentioned embodiment, but the present invention is not limited to the configuration of the above-mentioned embodiment, and naturally includes various modifications, alterations, and combinations that a person skilled in the art can make within the scope of the invention as defined in the claims of this application.

[0081] This application claims priority based on Japanese Patent Application No. 2023-145226, filed September 7, 2023, the disclosure of which is incorporated herein in its entirety by reference.

[0082] REFERENCE SIGNS LIST 10 Laminated glass 11 First glass plate 12 First interlayer 13 PDLC type light control film 14 Second interlayer 15 Second glass plate 16, 17, 18 Low-emissivity film 21 Transparent conductive layer 22 Reflection adjustment layer 23 Color tone correction layer 24 Adhesion improvement layer

Claims

1. A laminated glass having, in this order, a first glass plate, a first interlayer film, a PDLC type light control film, a second interlayer film, and a second glass plate, wherein the laminated glass has a total light transmittance of 10% or less and a haze value of 50% or more when the PDLC type light control film is turned off, the second glass plate has a low-emissivity film on the surface opposite to the second interlayer film, and the low-emissivity film has a visible light reflectance of 0.2% or more and 3.8% or less on the surface opposite to the second glass plate.

2. The laminated glass according to claim 1, wherein the low-emissivity film has, in order from the second glass plate side, a transparent conductive layer and a reflection adjustment layer, and the ratio of the thickness of the reflection adjustment layer to the thickness of the transparent conductive layer is 0.47 or more and 0.70 or less.

3. A laminated glass having, in this order, a first glass plate, a first intermediate film, a PDLC type light control film, a second intermediate film, and a second glass plate, wherein the laminated glass has a total light transmittance of 10% or less and a haze value of 50% or more when the PDLC type light control film is turned off, the second glass plate has a low emissivity film on the surface opposite to the second intermediate film side, the low emissivity film has, in this order from the second glass plate side, a transparent conductive layer and a reflection adjustment layer, and the ratio of the film thickness of the reflection adjustment layer to the film thickness of the transparent conductive layer is 0.47 or more and 0.70 or less.

4. The laminated glass according to claim 3, wherein the low-emissivity film has a visible light reflectance of 0.2% or more and 3.8% or less on the surface opposite to the second glass plate.

5. The laminated glass according to any one of claims 2 to 4, wherein the transparent conductive layer has a film thickness of 80 nm or more and 160 nm or less.

6. The laminated glass according to any one of claims 2 to 4, wherein the reflection adjustment layer has a film thickness of 50 nm or more and 100 nm or less.

7. The laminated glass according to any one of claims 2 to 4, wherein the transparent conductive layer is an ITO layer, a tin oxide layer, a fluorine-doped tin oxide layer, an antimony-doped tin oxide layer, a silver layer, a zirconium nitride layer, or a titanium nitride layer.

8. The laminated glass according to any one of claims 2 to 4, wherein the reflection adjustment layer contains an oxide or oxynitride of at least one metal selected from the group consisting of Ti, Nb, Ta, Zn, Al, In, Si, and Zr.

9. The laminated glass according to any one of claims 2 to 4, wherein the low-emissivity film further has a color correction layer, the color correction layer being composed of a plurality of layers including, in order from the second glass plate side, a first layer and a second layer, and the first layer has a higher refractive index for light with a wavelength of 630 nm than the second layer has a refractive index for light with a wavelength of 630 nm.

10. The laminated glass according to claim 9, wherein the first layer has a refractive index of 1.7 or more and 2.5 or less for light with a wavelength of 630 nm, and the second layer has a refractive index of 1.6 or less for light with a wavelength of 630 nm.

11. The laminated glass according to any one of claims 2 to 4, wherein the low-emissivity film further has a color correction layer, and the color correction layer contains an oxide or oxynitride of at least one metal selected from the group consisting of Ti, Nb, Ta, Zn, Al, In, Si, and Zr.

12. The laminated glass according to any one of claims 2 to 4, wherein the low-emissivity film has a color correction layer between the surface of the second glass plate facing the low-emissivity film and the transparent conductive layer, and the color correction layer has a thickness of 20 nm or more and 60 nm or less.

13. The laminated glass according to any one of claims 1 to 4, wherein the low-emissivity film has an emissivity of 0.3 or less on the surface opposite to the second glass plate.

14. The laminated glass according to any one of claims 2 to 4, wherein the low-emissivity film has an adhesion improving layer disposed between the transparent conductive layer and the reflection adjustment layer.

15. A laminated glass for vehicles, comprising the laminated glass according to any one of claims 1 to 4.

16. A laminated glass for a vehicle roof, comprising the laminated glass according to any one of claims 1 to 4.

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