JP7375663B2 - infrared shielding glass - Google Patents

Description

The present invention relates to infrared shielding glass.

Patent Document 1 discloses a laminated glass using an interlayer film including an infrared reflective layer. The laminated glass includes a first laminated glass member, a first resin layer, an infrared reflective layer, and a second laminated glass member in this order, and a first laminated glass member, a first resin layer, and an infrared reflective layer. , the second resin layer and the second laminated glass member may be provided in this order. In either case, since at least one of the first laminated glass member and the first resin layer is wedge-shaped, heat shielding properties and image display can be improved. The infrared reflective layer has a wedge shape in the same direction as the first laminated glass member and the first resin layer.

International Publication No. 2019/189734

In laminated glass, if the infrared shielding film and the interlayer film are wedge-shaped in the same direction, with the thickness changing in the same way from one end to the other, the image display as a head-up display will be good. , there was a risk of creating an area with poor heat insulation.

The present invention provides an infrared shielding glass that is excellent in image display as a head-up display and has excellent heat shielding properties over the entire surface of the laminated glass.

The present invention has a first glass plate, an intermediate film containing infrared shielding particles, a second glass plate, and an infrared shielding film in this order, the first glass plate, the intermediate film, the second glass plate, and the infrared shielding film. The total thickness of the infrared shielding film becomes thinner from the upper end side to the lower end side, the film thickness of the intermediate film becomes thinner from the upper end side to the lower end side, and the film thickness of the infrared shielding film is To provide an infrared shielding glass that becomes thicker from the upper end side to the lower end side.

According to the present invention, it is possible to provide an infrared shielding glass that is excellent in image display as a head-up display and has excellent heat shielding properties over the entire surface of the laminated glass.

FIG. 1 is a sectional view showing an example of infrared shielding glass. FIG. 2 is a sectional view showing another example of infrared shielding glass. FIG. 3 is a plan view showing an example of infrared shielding glass.

Embodiments of the present invention will be described below. In the present invention, the upper end side and the lower end side of the infrared shielding glass mean the upper end side and the lower end side in a state where it is attached to a vehicle.

As shown in FIG. 1, the infrared shielding glass 1 includes a first glass plate 2, an interlayer film 3 containing infrared shielding particles, a second glass 4, and an infrared shielding film 5 in this order. The first glass plate 2 is provided closer to the outdoor side than the second glass plate 4, and the second glass plate 4 is provided closer to the indoor side than the first glass plate 2. The total thickness of the first glass plate 2, interlayer film 3, second glass plate 4, and infrared shielding film 5 becomes thinner from the upper end to the lower end. The intermediate film 3 and the infrared shielding film 5 have wedge-shaped cross-sectional shapes in opposite directions. Specifically, the thickness of the intermediate film 3 becomes thinner from the upper end side to the lower end side, and the film thickness of the infrared shielding film 5 becomes thicker from the upper end side to the lower end side.

The first glass plate 2 may be made of either inorganic glass or organic glass. Examples of the inorganic glass include soda lime glass and aluminosilicate glass. Further, the inorganic glass may be either untempered glass or tempered glass. Unstrengthened glass is obtained by forming molten glass into a plate shape and slowly cooling it. Tempered glass is made by forming a compressive stress layer on the surface of untempered glass. The tempered glass may be either physically strengthened glass (for example, air-cooled strengthened glass) or chemically strengthened glass. On the other hand, examples of organic glass include transparent resins such as polycarbonate, acrylic resin, polyvinyl chloride, and polystyrene. The acrylic resin is, for example, polymethyl methacrylate. Note that, like the first glass plate 2, the second glass plate 4 may also be made of either inorganic glass or organic glass.

Since the first glass plate 2 is provided on the outdoor side of the second glass plate 4, it has a thickness of 1.8 mm or more in order to suppress the occurrence of scratches caused by flying stones. The thickness of the first glass plate 2 is 3.0 mm or less from the viewpoint of lightweight and formability. Note that the thickness of the first glass plate 2 may be constant or may vary depending on the position.

Since the second glass plate 4 is provided closer to the indoor side than the first glass plate 2, it may be thinner than the first glass plate 2. The thickness of the second glass plate 4 is 0.3 mm or more from the viewpoint of handling properties. Moreover, the thickness of the second glass plate 4 is 2.3 mm or less from the viewpoint of lightness and moldability. Note that the thickness of the second glass plate 3 may be constant or may vary depending on the position.

The intermediate film 3 is formed of a general resin, such as a thermoplastic resin such as polyvinyl butyral resin (PVB), ethylene-vinyl acetate copolymer resin (EVA), urethane, or ionomer resin. When the intermediate film 3 is heated, it exhibits adhesive properties. The intermediate film 3 may have either a single layer structure or a multilayer structure. The intermediate film 3 contains infrared shielding particles to improve heat shielding properties. As the infrared shielding particles, it is preferable to use cesium tungsten oxide particles or ITO (Indium Doped Tin Oxide) particles. Furthermore, the intermediate film 3 may have one or more selected from a sound insulation layer, a colored transparent layer, an ultraviolet cut layer, an infrared cut layer, and the like.

The thickness of the intermediate film 3 is thinner from the upper end side to the lower end side. The wedge angle θ of the interlayer film 3 is preferably 0.1×10 ⁻³ rad or more and 1.0×10 ⁻³ rad or less. The wedge angle θ is the angle between the boundary line between the interlayer film 3 and the first glass plate 2 and the boundary line between the interlayer film 3 and the second glass plate 4. By making the interlayer film 3 wedge-shaped in cross-section, it is possible to suppress the occurrence of double images in image display on a head-up display. On the other hand, the visible light transmittance may increase and the infrared shielding property may decrease from the upper end side to the lower end side.

The film thickness of the infrared shielding film 5 increases from the upper end side to the lower end side. That is, from the upper end side to the lower end side, the visible light transmittance decreases and the infrared shielding ability increases. In this way, by making the cross-sectional shape of the infrared shielding film 5 into a wedge shape in the opposite direction to the wedge shape of the intermediate film 3, it is possible to achieve excellent image display as a head-up display, and to improve visible light transmittance from the upper end side to the lower end side. Uniform infrared shielding properties can be achieved.

As shown in FIGS. 2 and 3, the upper end of the infrared shielding film 5 may be located below the upper ends of the first glass plate 2 and the second glass plate 4. Similarly, the lower end of the infrared shielding film 5 may be located above the lower ends of the first glass plate 2 and the second glass plate 4.

The infrared shielding film 5 may be provided directly on the surface of the first glass plate 2 or the second glass plate 4, or may be provided via an adhesive layer and a base material layer. The infrared shielding film 5 may be a single layer film or a multilayer film of two or more layers. In the case of a single layer film, it contains silicon oxide and an infrared shielding compound. Infrared shielding compounds include tin-doped indium oxide, antimony-doped tin oxide, aluminum-doped zinc oxide, indium-doped zinc oxide, tin-doped zinc oxide, silicon-doped zinc oxide, lanthanum hexaboride, and cerium hexaboride. In the case of a multilayer film, it may be a multilayer resin film in which two or more types of thermoplastic resin layers having different refractive indexes are laminated alternately or randomly, or it may be a liquid crystal film in which cholesteric liquid crystal layers are laminated.

The infrared shielding film 5 is a single layer film, and is preferably provided directly above the second glass plate 4. Since the infrared shielding film 5 does not have a base material layer or an adhesive layer, it is possible to suppress the generation of multiple images due to reflection and refraction that occur at the interface between the base material layer and the adhesive layer, and the image display as a head-up display can be clearly displayed. Can be done.

The film thickness at the first reference point 10 cm downward from the upper end of the infrared shielding film 5 is A [mm], the film thickness at the second reference point 10 cm upward from the lower end of the infrared shielding film 5 is B [mm], The thickness of the intermediate film 3 at the same height as the second reference point is C [mm], and the film thickness of the intermediate film 3 at the same height as the first reference point is C + L × θ [mm]. In this case, it is preferable that the thickness of the infrared shielding film 5 and the thickness of the intermediate film 3 satisfy formula (1). Here, L is the distance [mm] from the first reference point to the second reference point of the infrared shielding film 5, and θ is the wedge angle [rad] of the interlayer film. θ is 0.1×10 ⁻³ or more.
|B×C−A×(C+L×θ)|≦4×10 ^-3 ...Formula (1)
When the film thickness of the infrared shielding film 5 and the film thickness of the intermediate film 3 satisfy formula (1), the film thickness (C + L × θ) on the upper end side of the intermediate film 3 and the film thickness (C) on the lower end side are The ratio ((C+L×θ)/C) is almost the same as the ratio (B/A) between the film thickness (B) on the lower end side and the film thickness (A) on the upper end side of the infrared shielding film 5. , visible light transmittance and infrared shielding properties can be made uniform from the upper end side to the lower end side. Equation (1) indicates that the difference in ratio is below a certain value. The lower limit value on the left side of equation (1) is zero.

Further, it is preferable that the thickness of the infrared shielding film 5 and the thickness of the intermediate film 3 satisfy formula (2).
|B×C−A×(C+L×θ)|/(A×C)≦0.4 ...Formula (2)
When the film thickness of the infrared shielding film 5 and the film thickness of the intermediate film 3 satisfy formula (2), visible light transmittance and infrared shielding property are improved from the upper end side to the lower end side for the same reason as the formula (1). Can be done evenly. Equation (2) is a dimensionless version of Equation (1). The lower limit value on the left side of equation (2) is zero.

Next, a method for manufacturing the infrared shielding glass 1 will be explained.

The first glass plate 2 and the second glass plate 4 are heat treated and bent. The bent first glass plate 2, the interlayer film 3, and the bent second glass plate 4 are stacked in this order to produce a polymer, and the produced polymer is pressurized and heat-treated using an autoclave or the like. Next, an infrared shielding film 5 is formed on the indoor side surface of the second glass plate 4. The infrared shielding film 5 is formed by applying a composition containing an infrared shielding compound to the outdoor surface of the second glass plate, drying, and curing. As a coating method, a flow coating method is preferred since it is easy to create a difference in film thickness. The flow coating method is a method in which a composition is injected onto the top of a glass plate using a nozzle while the glass plate is held vertically. The composition injected onto the top of the glass plate flows vertically downward, making it possible to increase the film thickness at the bottom of the glass plate compared to the film thickness at the top of the glass plate. The film thickness distribution from the top to the bottom can be adjusted by adjusting the holding angle of the glass plate, the kinematic viscosity of the composition, and the like.

The constituent elements and manufacturing method of the infrared shielding glass 1 according to one embodiment of the present invention have been described above. These are merely examples, and the present invention includes other embodiments that do not interfere with the purpose.

EXAMPLES Hereinafter, the present invention will be explained in detail with reference to Examples, but the present invention is not limited thereto. Examples 1 to 4 are examples, and examples 5 and 6 are comparative examples.

(Example 1)
In a round bottom flask, add 18.98 g of 1-propanol, 13.60 g of methanol, 6.33 g of 0.1N nitric acid aqueous solution, 10.52 g of tetraethoxysilane, and 11 g of bisalkoxysilane (manufactured by Shin-Etsu Chemical Co., Ltd., KBM3066). .50g, 11.23g of epoxy silane (manufactured by Shin-Etsu Chemical Co., Ltd., KBM-403), 15.35g of epoxy resin (manufactured by Nagase ChemteX, EX614B), 1.87g of aluminum acetylacetonate, aluminum-based curing catalyst ( 4.16 g of CAT-AC (manufactured by Shin-Etsu Chemical Co., Ltd.) and 0.07 g of a surface conditioner (BYK307, manufactured by BYK Chemie Co., Ltd.) were added, and the mixture was stirred at 28° C. for 2.5 hours. Finally, 6.38 g of a cesium tungsten oxide dispersion (manufactured by Sumitomo Metal Mining Co., Ltd., CWO dispersion with a concentration of 20% by mass) was added to obtain Composition 1 with a solid content concentration of 39.1%.

Laminated glass 1 shown in Table 2 was prepared.

The composition 1 was poured onto the concave surface of the laminated glass along the upper side while the laminated glass 1 was held vertically with the upper end facing upward. The pouring position was 20 mm below the upper end of the laminated glass 1. Thereafter, the glass was heated at 100° C. for 30 minutes in the air to obtain an infrared shielding glass 1 having an infrared shielding film 5. Table 3 shows the composition of the obtained infrared shielding film 5.

(Examples 2 to 6)
In addition to Composition 1 as described in Example 1, Composition 2 was obtained. The composition of Composition 2 is shown in Table 1. Composition 2 was prepared in the same manner as Composition 1, except that an ITO dispersion (PI-6A, manufactured by Mitsubishi Materials Corporation, 30% by mass) was used instead of the cesium tungsten oxide dispersion.

Laminated glasses 1 and 2 shown in Table 2 were prepared. Laminated glass 2 was prepared in the same manner as laminated glass 1 except that the combinations shown in Table 2 were used.

Laminated glasses 1 and 2 and compositions 1 and 2 were combined as shown in Table 4 to obtain infrared shielding glasses 2 to 6 having an infrared shielding film 5. Infrared shielding glasses 5 and 6 were obtained in the same manner as infrared shielding glasses 1 and 2, except that the composition was poured onto the laminated glasses 1 and 2 so that the lower ends of the glasses were facing upward.

Table 4 shows the evaluation results for infrared shielding glasses 1 to 6.

(Visible light transmittance)
The visible light transmittance described in JIS R3212 was calculated from the results of measuring the transmittance at each wavelength of infrared shielding glasses 1 to 6 using a spectrophotometer (manufactured by Hitachi, Ltd.: U-4100).

(Infrared transmittance)
Using a spectrophotometer (manufactured by Hitachi, Ltd.: U-4100), the transmittance (T1500) of the infrared shielding glasses 1 to 6 at a wavelength of 1500 nm was measured.

(Image displayability)
Infrared shielding glasses 1 to 6 were installed in the vehicle to form a head-up display. Project an image using a projector and view it from the driver's seat of the vehicle. If the projected image can be clearly seen, it is "OK."If a double or triple image occurs and the projected image cannot be seen clearly, it is "OK." It was ``NG''.

表４に示す通り、赤外線遮蔽膜５の膜厚が、上端側から下端側に向かって厚くなる例１～４では、赤外線遮蔽ガラス１の可視光透過率の上端及び下端の差を１．２％以下に、赤外線透過率の差を０．８％以下に抑えた。一方、赤外線遮蔽膜５の膜厚が上端側から下端側に向かって厚くなる例５、６では、赤外線遮蔽ガラス１の可視光透過率の上端及び下端の差が１．７％以上となり、赤外線透過率の差が２．５％以上となった。

As shown in Table 4, in Examples 1 to 4, where the film thickness of the infrared shielding film 5 increases from the upper end side to the lower end side, the difference in visible light transmittance of the infrared shielding glass 1 between the upper end and the lower end is 1.2. % or less, and the difference in infrared transmittance was suppressed to 0.8% or less. On the other hand, in Examples 5 and 6 where the film thickness of the infrared shielding film 5 increases from the upper end side to the lower end side, the difference in the visible light transmittance of the infrared shielding glass 1 between the upper end and the lower end is 1.7% or more, and the infrared The difference in transmittance was 2.5% or more.

The infrared shielding glass of the present invention has excellent image display as a head-up display, and has excellent heat shielding properties over the entire surface of the laminated glass. Therefore, it can be applied to windshield glass and side glass of automobiles.

1: Infrared shielding glass 2: First glass plate 3: Intermediate film 4: Second glass plate 5: Infrared shielding film

Claims (5)

comprising a first glass plate, an intermediate film containing infrared shielding particles, a second glass plate, and an infrared shielding film in this order;
The total thickness of the first glass plate, the intermediate film, the second glass plate, and the infrared shielding film becomes thinner from the upper end side to the lower end side,
The thickness of the intermediate film becomes thinner from the upper end side to the lower end side,
The infrared shielding glass is such that the thickness of the infrared shielding film increases from the upper end side to the lower end side. The infrared shielding glass according to claim 1, wherein the first glass plate is provided on the outdoor side and the infrared shielding film is provided on the indoor side. The infrared shielding glass according to claim 1 or 2, wherein the infrared shielding film is a single layer film and is provided directly above the glass. The film thickness at a first reference point 10 cm downward from the upper end of the infrared shielding film is A [mm], the film thickness at a second reference point 10 cm upward from the lower end of the infrared shielding film is B [mm], The film thickness at a point of the intermediate film at the same height as the second reference point is C [mm], the film thickness at a point of the intermediate film at the same height as the first reference point is C + L × θ [mm], The infrared shielding glass according to any one of claims 1 to 3, which satisfies formula (1) when:
|B×C−A×(C+L×θ)|≦4×10 ^-3 ...Formula (1)
Here, L is the length [mm] of the infrared shielding film from the first reference point to the second reference point, and θ is the wedge angle [rad] of the intermediate film. θ is 0.1×10 ⁻³ or more. The film thickness at a first reference point 10 cm downward from the upper end of the infrared shielding film is A [mm], the film thickness at a second reference point 10 cm upward from the lower end of the infrared shielding film is B [mm], The film thickness at a point of the intermediate film at the same height as the second reference point is C [mm], the film thickness at a point of the intermediate film at the same height as the first reference point is C + L × θ [mm], The infrared shielding glass according to any one of claims 1 to 4, which satisfies formula (2) when:
|B×C−A×(C+L×θ)|/(A×C)≦0.4 ...Formula (2)
Here, L is the length [mm] of the infrared shielding film from the first reference point to the second reference point, and θ is the wedge angle [rad] of the intermediate film. θ is 0.1×10 ⁻³ or more.

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