Vehicle window glass

Abstract

Provided is vehicle window glass which, even when comprising laminated glass and a functional member enclosed therein, can retain the strength of the laminated glass. Vehicle window glass (1) according to one embodiment of the present disclosure comprises a first glass plate (11) disposed on a vehicle exterior side, a second glass plate (12) disposed on a vehicle interior side, a first interlayer (13) interposed between the first glass plate (11) and the second glass plate (12), and a functional member (14) interposed between the first glass plate (11) and the second glass plate (12). The functional member (14) has a multilayer configuration composed of a dielectric layer (21) and a conductor layer (22). The vehicle window glass (1) includes a region (20) comprising the second glass plate (12), the first interlayer (13), the dielectric layer (21), and the conductor layer (22) which lie in this order.

Description

Vehicle window glass

[0001] FIELD OF THE DISCLOSURE The present disclosure relates to vehicle glazings.

[0002] In recent years, there has been an acceleration in the development of automobiles and other means of transportation that can achieve high-capacity communications and highly automated driving using radio waves in the 4G-LTE / 5G frequency band for infotainment. As a result, there is a trend toward vehicles being equipped with antennas having conductors for transmitting and receiving radio waves in a specific frequency band.

[0003] For example, in order to obtain information about the area ahead of the vehicle, it is being considered to mount such an antenna on a vehicle window glass such as a windshield. From the viewpoint of safety, automobile windshields are required by law to be made of laminated glass having an intermediate layer sandwiched between two glass sheets, and a technique for enclosing an antenna inside such laminated glass is known.

[0004] For example, Patent Document 1 discloses a structure in which an antenna for terrestrial wave bands II to V is placed inside a composite glass plate and power is supplied by a flat conductor. Furthermore, Patent Documents 2 and 3 disclose structures in which an antenna (e.g., 28 GHz) suitable for transmitting and receiving radio waves in high frequency bands such as millimeter waves is placed inside laminated glass / double glazing, connected by a transmission line / signal conductor, and power is supplied from outside the glass.

[0005] Patent Publication No. 2014-514836 International Publication No. 2020 / 230819 Patent Publication No. 2021-519524

[0006] As described above, when a film-like antenna (functional component) is enclosed in laminated glass, the strength of the laminated glass against impacts from the outside of the vehicle is reduced in the area where the antenna is provided, and the laminated glass may not be able to maintain an appropriate strength, and the safety of the laminated glass may not be ensured.

[0007] In view of the above problems, an object of the present disclosure is to provide a vehicle window glass that can maintain the strength of the laminated glass against impacts from outside the vehicle even when a functional component is enclosed in the laminated glass.

[0008] A vehicle window glass according to one aspect of the present disclosure has the following configuration.

[0009] [1] A vehicle window glass to be attached to an opening of a vehicle, the vehicle window glass comprising: a first glass plate arranged on an exterior side of the vehicle; a second glass plate arranged on an interior side of the vehicle; a first intermediate layer arranged between the first glass plate and the second glass plate; and a functional member arranged between the first glass plate and the second glass plate, wherein the functional member has a configuration in which a dielectric layer and a conductor layer are laminated, and the vehicle window glass includes a region in which the second glass plate, the first intermediate layer, the dielectric layer, and the conductor layer are laminated in this order.

[0010] [2] The vehicle window glass according to [1], wherein the functional member further comprises an adhesive layer, and the vehicle window glass includes a region in which the second glass plate, the first intermediate layer, the dielectric layer, the conductor layer, and the adhesive layer are laminated in this order.

[0011] [3] The vehicle window glass according to [2], wherein the adhesive layer is in contact with the first glass plate.

[0012] [4] The vehicle window glass according to [2], wherein a second intermediate layer is disposed between the first glass plate and the adhesive layer.

[0013] [5] The vehicle window glass according to [4], wherein the thickness of the first intermediate layer disposed between the second glass plate and the dielectric layer and the thickness of the second intermediate layer disposed between the first glass plate and the adhesive layer are approximately the same.

[0014] [6] The vehicle window glass according to [2], wherein the conductor layer has, in a plan view, a linear portion and a first cutout portion that is surrounded by the linear portion and cut out in the thickness direction of the conductor layer.

[0015] [7] The vehicle window glass according to [6], wherein the dielectric layer has a second cutout portion at a position overlapping the first cutout portion of the conductor layer in a plan view.

[0016] [8] The vehicle window glass according to [7], wherein the adhesive layer has a third cutout portion at a position overlapping the first cutout portion of the conductor layer and the second cutout portion of the dielectric layer in a plan view.

[0017] [9] The vehicle window glass according to [8], wherein the first to third cutout portions of the functional member are filled with the material of the first intermediate layer.

[0018]

[10] The vehicle window glass according to any one of [6] to [9], wherein the adhesive layer is in contact with the first glass plate.

[0019]

[11] The vehicle window glass according to any one of [6] to [9], wherein a second intermediate layer is disposed between the first glass plate and the adhesive layer.

[0020]

[12] The vehicle window glass according to

[11] , wherein a thickness of a first intermediate layer disposed between the second glass plate and the dielectric layer and a thickness of a second intermediate layer disposed between the first glass plate and the adhesive layer are approximately the same.

[0021]

[13] The vehicle window glass according to any one of [1] to

[12] , wherein the conductor layer is a flat conductor having slots formed therein.

[0022]

[14] The vehicle window glass according to any one of [1] to

[13] , wherein the functional member is an antenna capable of transmitting and receiving radio waves at a predetermined frequency.

[0023]

[15] The vehicle window glass according to

[14] , wherein the antenna includes a feeding electrode and a ground electrode on the conductor layer.

[0024] The present disclosure makes it possible to provide a vehicle window glass that can maintain the strength of the laminated glass against impacts from outside the vehicle even when a functional component is enclosed in the laminated glass.

[0025] 5 is a cross-sectional view showing an example of the configuration of a vehicle window glass according to embodiment 1. FIG. 6 is a cross-sectional view showing another example of the configuration of a vehicle window glass according to embodiment 1. FIG. 7 is a cross-sectional view showing another example of the configuration of a vehicle window glass according to embodiment 1. FIG. 8 is a cross-sectional view showing an example of the configuration of a vehicle window glass according to embodiment 2. FIG. 9 is a plan view showing an example of the configuration of a functional member. FIG. 10 is a plan view showing an example of the configuration of a functional member. FIG. 11 is an enlarged plan view of region A in FIG. 5. FIG. 12 is a cross-sectional view showing an example of a manufacturing process for a vehicle window glass according to an embodiment. FIG. 13 is a plan view showing another example of the configuration of a functional member. FIG. 14 is a cross-sectional view showing another example of the configuration of a vehicle window glass according to embodiment. FIG. 15 is a cross-sectional view showing another example of the configuration of a vehicle window glass according to embodiment. FIG. 16 is a cross-sectional view showing another example of the configuration of a vehicle window glass according to embodiment 2.

[0026] First Embodiment An embodiment will now be described with reference to the drawings. Fig. 1 is a cross-sectional view showing an example of the configuration of a vehicle window glass according to the first embodiment. As shown in Fig. 1, the vehicle window glass 1 according to the present embodiment includes a first glass sheet 11, a second glass sheet 12, an intermediate layer (first intermediate layer) 13 arranged between the first glass sheet 11 and the second glass sheet 12, and a functional member 14 arranged between the first glass sheet 11 and the second glass sheet 12.

[0027] The functional member 14 has a configuration in which a dielectric layer 21 and a conductor layer 22 are laminated together. The vehicle window glass 1 according to this embodiment includes a region 20 in which the second glass sheet 12, the intermediate layer 13, the dielectric layer 21, and the conductor layer 22 are laminated together in this order. In regions other than region 20, the first glass sheet 11 and the second glass sheet 12 are bonded together by the intermediate layer 13. The vehicle window glass 1 according to this embodiment is a vehicle window glass that is attached to an opening in a vehicle, and can be used, for example, for at least one of a windshield, rear glass, side glass, and roof glass of a vehicle.

[0028] The vehicle window glass 1 according to this embodiment may be flat or curved. It may also have a shape including both flat and curved surfaces. The first glass sheet 11 and the second glass sheet 12 may each be a flat sheet or a curved sheet. The curved sheet may have a single curved shape curved in one direction, or a three-dimensional shape curved in two or more directions. The three-dimensional shape may be, for example, a complex curved shape curved in two orthogonal directions. In the following example, a case will be described in which both the first glass sheet 11 and the second glass sheet 12 are flat sheets, but the same explanation can be applied to the case in which at least one of them is a curved sheet.

[0029] The outer edge shapes of the first glass sheet 11 and the second glass sheet 12 in a plan view may be any shape, but are preferably rectangular, trapezoidal, or triangular, for example. In this embodiment, when the vehicle window glass 1 is installed in a vehicle, the first glass sheet 11 is arranged on the exterior side of the vehicle, and the second glass sheet 12 is arranged on the interior side of the vehicle.

[0030] The first and second glass plates 11, 12 may be made of, for example, transparent inorganic glass. For example, soda-lime glass, aluminosilicate glass, borosilicate glass, alkali-free glass, quartz glass, etc. The first and second glass plates 11, 12 may be manufactured using, for example, a float process or a fusion process, but are not limited to these manufacturing methods.

[0031] The thickness of each of the first and second glass sheets 11, 12 is, for example, 0.1 mm to 10 mm, and from the viewpoint of resistance to stone chipping, is preferably 0.3 mm to 3.0 mm, more preferably 1.1 mm to 2.6 mm, and even more preferably 1.7 mm to 2.1 mm. The thicknesses of the first and second glass sheets 11, 12 may be the same as or different from each other. For example, the thickness of the first glass sheet 11 located on the vehicle exterior side may be thicker than the thickness of the second glass sheet 12 located on the vehicle interior side. In this way, if the thickness of the first glass sheet 11 located on the vehicle exterior side is thicker, the strength of the vehicle window glass 1 against objects flying toward the vehicle window glass 1 is improved.

[0032] The intermediate layer 13 is disposed so as to be sandwiched between the first glass plate 11 and the second glass plate 12. There are no particular limitations on the thickness of the intermediate layer 13, but it is preferably, for example, 1.10 mm or less. The thickness of the intermediate layer 13 is preferably 0.50 mm or more, and more preferably 0.70 mm or more. By setting the thickness of the intermediate layer 13 within this range, the transparency of the vehicle window glass can be ensured and the weight of the vehicle window glass can be prevented from becoming excessively large.

[0033] The intermediate layer 13 can be made of a material including, for example, polyvinyl butyral (PVB), ethylene vinyl acetate (EVA), cycloolefin polymer, urethane resin, polyvinylidene fluoride resin (PVDF), etc. A plasticizer may be added to the intermediate layer 13. Examples of the plasticizer that can be used include organic ester plasticizers such as monobasic organic acid esters and polybasic organic acid esters, and organic phosphate plasticizers such as organic phosphate plasticizers and organic phosphite plasticizers.

[0034] The functional member 14 has a laminated structure of a dielectric layer 21 and a conductor layer 22. The dielectric layer 21 can be made of a resin film having a predetermined thickness. For example, the dielectric layer 21 may be made of a TAC (Triacetylcellulose) film.

[0035] The conductor layer 22 can be made of a conductive material such as metal. The shape of the conductor layer 22 can be determined depending on the function of the functional member 14. For example, if the functional member 14 is an antenna, the shape of the conductor layer 22 can be determined depending on the frequency band of the radio waves to be transmitted and received. For example, the conductor layer 22 may be a flat conductor with a slot for the antenna formed therein. Furthermore, the functional member 14 may be a heater, in which case the conductor layer 22 can be made of an electric heating wire having a predetermined resistance value.

[0036] The vehicle window glass 1 according to this embodiment is configured so that the second glass sheet 12, the intermediate layer 13, the dielectric layer 21, and the conductor layer 22 are laminated in this order in the region 20 where the functional member 14 is provided. In other words, the functional member 14 is disposed on the first glass sheet 11 side, and the intermediate layer 13 is disposed between the second glass sheet 12 and the functional member 14.

[0037] This embodiment provides a vehicle window glass that can maintain the strength of the laminated glass even when the functional member 14 is encapsulated in the laminated glass. Specifically, in this embodiment, the intermediate layer 13 is disposed between the second glass sheet 12 and the functional member 14 (dielectric layer 21). Therefore, even when an impact is applied to the first glass sheet 11 from the vehicle exterior side in the region 20 where the functional member 14 is provided, the intermediate layer 13 can maintain the adhesion of the second glass sheet 12. This prevents the second glass sheet 12 from breaking and scattering fragments of the second glass sheet 12 toward the vehicle interior side, or prevents a colliding object from penetrating the second glass sheet 12. Furthermore, the vehicle window glass 1 includes the second glass sheet 12, the intermediate layer 13, the dielectric layer 21, and the conductor layer 22 stacked in this order in the region 20 where the functional member 14 is provided. Therefore, even if the conductor layer 22 is damaged by an impact applied from the outside of the vehicle, i.e., from the side of the first glass sheet 11, the presence of the dielectric layer 21 between the conductor layer 22 and the intermediate layer 13 prevents the damaged conductor layer 22 from slicing through the intermediate layer 13, damaging the second glass sheet 12 and scattering the second glass sheet 12 inside the vehicle. Furthermore, if a plasticizer is added to the intermediate layer 13, the presence of the dielectric layer 21 between the conductor layer 22 and the intermediate layer 13 can prevent the plasticizer added to the intermediate layer 13 from eroding the intermediate layer 13.

[0038] In this embodiment, when forming the vehicle window glass 1, the first glass sheet 11, the functional component 14, the intermediate layer 13, and the second glass sheet 12 are laminated in this order and placed in a vacuum bag such as a rubber bag. The vacuum bag is then connected to an exhaust system, and the pressure inside the vacuum bag is reduced (deaerated) to a reduced pressure (absolute pressure) of approximately −65 kPa to −100 kPa, followed by heating and pressurization at a temperature of approximately 70°C to 110°C. Furthermore, a pressure bonding process is performed in which heating and pressurization are performed at a temperature of approximately 100°C to 140°C and a pressure of 0.6 MPa to 1.3 MPa, thereby obtaining a vehicle window glass 1 with excellent durability. Note that the method for forming the vehicle window glass 1 is not limited to this method, and the vehicle window glass 1 may be formed using other manufacturing methods.

[0039] Fig. 2 is a cross-sectional view showing another example of the configuration of the vehicle window glass according to the first embodiment. In this embodiment, as in the vehicle window glass 1a shown in Fig. 2, the functional member 14 may further include an adhesive layer 23. That is, the functional member 14 may have a configuration in which a dielectric layer 21, a conductor layer 22, and an adhesive layer 23 are laminated in this order. In this case, the vehicle window glass 1a is configured such that the second glass sheet 12, the intermediate layer 13, the dielectric layer 21, the conductor layer 22, and the adhesive layer 23 are laminated in this order in the region 20 in which the functional member 14 is provided.

[0040] The adhesive layer 23 can be formed using, for example, a transparent adhesive material, i.e., an optical clear adhesive (OCA). For example, an acrylic-based, silicone-based, epoxy-based, or urethane acrylate-based optical adhesive can be used for the adhesive layer 23. The adhesive layer 23 is in contact with the first glass plate 11. For example, the functional member 14 may be adhered to the first glass plate 11 using the adhesive layer 23. When manufacturing the vehicle window glass 1a, by previously adhering the functional member 14 to the first glass plate 11 using the adhesive layer 23, it is possible to prevent the functional member 14 from being displaced relative to the first glass plate 11 when the vehicle window glass 1a is heated and pressurized to melt the intermediate layer 13.

[0041] Fig. 3 is a cross-sectional view showing another example of the configuration of the vehicle window glass according to the first embodiment. In this embodiment, as in the vehicle window glass 1b shown in Fig. 3, an intermediate layer 18 (second intermediate layer) may be disposed between the first glass sheet 11 and the adhesive layer 23. By providing the intermediate layer 18 between the first glass sheet 11 and the adhesive layer 23 in this manner, the strength of the vehicle window glass can be improved. For example, when manufacturing the vehicle window glass 1b, the intermediate layer 13 and the intermediate layer 18 can be disposed so as to sandwich the functional component 14, thereby disposing the intermediate layers 13 and 18 on both sides of the functional component 14.

[0042] For example, the thickness of the intermediate layer 13 disposed between the second glass plate 12 and the dielectric layer 21 and the thickness of the intermediate layer 18 disposed between the first glass plate 11 and the adhesive layer 23 may be configured to be approximately the same. Here, "approximately the same" means that the difference in thickness between the intermediate layers 13 and 18 is within a 10% range. The thickness of the intermediate layer 18, like the thickness of the intermediate layer 13, is preferably 0.50 mm or more, and more preferably 0.70 mm or more. The thickness of the intermediate layer 18 is preferably 1.10 mm or less.

[0043] <Second embodiment> Next, a second embodiment will be described. Fig. 4 is a cross-sectional view showing an example of the configuration of a vehicle window glass according to the second embodiment. Fig. 5 is a plan view showing an example of the configuration of a functional member provided in the vehicle window glass according to the second embodiment. Fig. 4 is a cross-sectional view taken along the section line IV-IV shown in Fig. 5. In the vehicle window glass 2 according to the second embodiment, the configuration of the functional member 15 differs from that described in the first embodiment. Other than this, the configuration is the same as that of the vehicle window glass described in the first embodiment, so the same components are denoted by the same reference numerals and redundant description will be omitted.

[0044] As shown in Figure 4, the vehicle window glass 2 according to this embodiment has a first glass plate 11, a second glass plate 12, an intermediate layer (first intermediate layer) 13 sandwiched between the first glass plate 11 and the second glass plate 12, and a functional member 15 arranged between the first glass plate 11 and the second glass plate 12.

[0045] The functional member 15 has a configuration in which a dielectric layer 21, a conductor layer 22, and an adhesive layer 23 are laminated. The vehicle window glass 2 according to this embodiment includes a region in which the second glass sheet 12, the intermediate layer 13, the dielectric layer 21, the conductor layer 22, and the adhesive layer 23 are laminated in this order. Typically, the adhesive layer 23 is in contact with (adhered to) the first glass sheet 11. In this embodiment, the essential elements constituting the functional member 15 are the dielectric layer 21 and the conductor layer 22, and the adhesive layer 23 can be omitted. In this case, the functional member 15 has the dielectric layer 21 and the conductor layer 22 laminated in this order from the side closest to the intermediate layer 13.

[0046] As shown in Figures 4 and 5, the functional member 15 has a linear portion 16 and a cutout portion 17 in a plan view of the first glass plate 11. The cutout portion 17 is surrounded by the linear portion 16 and is cut out in the thickness direction of the functional member 15. In other words, the conductor layer 22 has the linear portion 16 and a cutout portion 17 (first cutout portion) that is surrounded by the linear portion 16 and cut out in the thickness direction of the conductor layer 22. The dielectric layer 21 has the cutout portion 17 (second cutout portion) in a position that overlaps the cutout portion 17 of the conductor layer 22 in a plan view. The adhesive layer 23 has the cutout portion 17 (third cutout portion) in a position that overlaps the cutout portion 17 of the conductor layer 22 and the cutout portion 17 of the dielectric layer 21 in a plan view. In this embodiment, the material of the intermediate layer 13 is filled into the cutout portions 17 (first to third cutout portions) of the functional member 15. When the cutout portions 17 are not included (i.e., when only the linear portions 16 are included), the cross-sectional view shown in Fig. 4 shows a cross-sectional shape in which the layers of the functional member 15 are continuous in the horizontal direction.

[0047] The functional member 15 shown in Fig. 5 is an antenna capable of transmitting and receiving radio waves of a predetermined frequency. The functional member 15 includes a feeding electrode 31 and a ground electrode 32. Note that the cutout portion 17 becomes a void portion when it is not filled with the material of the intermediate layer 13. In this embodiment, the functional member 15 functions as an antenna.

[0048] The dielectric layer 21 (see FIG. 4) of the functional member 15 can be made of a resin film having a predetermined thickness. For example, the dielectric layer 21 may be made of a TAC (Triacetylcellulose) film.

[0049] The conductor layer 22 can be formed using a mesh-like conductor. For example, the conductor layer 22 can be formed using a mesh-like copper foil or aluminum foil. By forming the conductor layer 22 using a mesh-like conductor, the field of view of the occupant can be ensured. The shape of the conductor layer 22 (antenna shape) can be determined depending on the frequency band of the radio waves to be transmitted and received. In this specification, the shape of the mesh formed by the linear portions 16 and the cutout portions 17 is referred to as "mesh-like."

[0050] The adhesive layer 23 can be made of, for example, a transparent adhesive material, i.e., an optical adhesive (OCA). For example, an acrylic, silicone, epoxy, or urethane acrylate optical adhesive can be used for the adhesive layer 23.

[0051] For example, in this embodiment, a conductor layer 22 and an adhesive layer 23 may be laminated on a dielectric layer 21, and the laminate may be cut out using a mold having an antenna pattern (see Figure 5), thereby forming a functional component (antenna) 15 having a cutout portion 17.

[0052] As shown in Figures 4 and 5, in this embodiment, the line width W1 of the linear portion 16 of the functional member 15 is preferably 7 mm or less, more preferably 5 mm or less, and even more preferably 1 mm or less, when viewed in plan of the first glass plate 11. Furthermore, the length W2 of the cutout portion 17 is preferably 1 mm or more, more preferably 3 mm or more, and even more preferably 4 mm or more, when viewed in plan of the first glass plate 11. Furthermore, when viewed in plan of the first glass plate 11, the ratio of the area of ​​the cutout portion 17 to the area of ​​the region surrounded by the outer edge of the functional member 15 is preferably in the range of 4.5% to 45%, more preferably 20% to 45%, and even more preferably 30% to 45%. This configuration allows the laminated glass to maintain the appropriate strength and ensure the safety of the laminated glass.

[0053] 6 , when a rectangular region 38 having the smallest area encompassing the functional member 15 is defined in a plan view of the first glass plate 11, the length of at least one side of the rectangular region 38 is preferably 25 mm or more, more preferably 30 mm or more, and even more preferably 40 mm or more. There is no particular limitation on the maximum value of the length of one side, but an example of this length is 150 mm or less.

[0054] FIG. 7 is an enlarged plan view of region A in FIG. 5 . As shown in FIG. 7 , in this embodiment, the conductor layer 22 constituting the linear portion 16 may include a portion formed of mesh-like thin wires within the linear portion 16 in a plan view of the first glass plate 11. By forming the linear portion 16 using mesh-like thin wires in this manner, the transparency of the functional component 15 can be improved, thereby ensuring the occupant's field of vision. That is, in this embodiment, by forming the linear portion 16 and the cutout portion 17 in a mesh-like shape and forming the linear portion 16 using mesh-like thin wires, the transparency of the functional component 15 can be effectively improved and the occupant's field of vision can be ensured. The width of the mesh-like thin wires can be exemplified as being in the range of 0.01 mm to 0.1 mm. Furthermore, the laminated glass can maintain the appropriate strength and ensure the safety of the laminated glass. Furthermore, in this embodiment, the linear portion 16 does not have to be mesh-like; in this case, it can be formed using solid thin wires. The width of the solid thin wires can be exemplified as being in the range of 0.5 mm to 4.0 mm.

[0055] 5 , the cutouts 17 may be arranged in a matrix pattern along two perpendicular sides in a functional member region surrounded by the outer edge of the functional member 15 in a plan view of the first glass plate 11. The directions of the two perpendicular sides are not limited to the arrangement of the two sides along the outer edge of the rectangular region 38, and any direction can be set. For example, the directions of the two perpendicular sides may be directions that form a 45° angle with the outer edge of the rectangular region 38, and the cutouts 17 may be arranged in a matrix pattern. The cutouts 17 may also be arranged with an irregular outer edge shape in a region including the functional member 15 in a plan view of the first glass plate 11. In other words, the cutouts 17 may be arranged randomly in the region including the functional member 15.

[0056] As described above, in this embodiment, the intermediate layer 13 is disposed between the second glass sheet 12 and the functional member 15 (dielectric layer 21). Therefore, even if an impact is applied to the first glass sheet 11 from the vehicle exterior to the region where the functional member 15 is provided, the second glass sheet 12 can remain bonded by the intermediate layer 13. This prevents the second glass sheet 12 from breaking and scattering fragments of the second glass sheet 12 toward the vehicle interior, or prevents a colliding object from penetrating the second glass sheet 12.

[0057] FIG. 8 is a cross-sectional view showing an example of a manufacturing process for a vehicle window glass according to this embodiment. To form a vehicle window glass 2 according to this embodiment, as shown in the upper diagram of FIG. 8 , a first glass sheet 11, a functional component 15, an intermediate layer 13, and a second glass sheet 12 are laminated in this order and placed in a vacuum bag such as a rubber bag. The vacuum bag is then connected to an exhaust system, and the pressure inside the vacuum bag is reduced (deaerated) to a reduced pressure (absolute pressure) of approximately −65 kPa to −100 kPa, followed by heating and pressurization at a temperature of approximately 70°C to 110°C. A heating and pressurization process is then performed at a temperature of approximately 100°C to 140°C and a pressure of 0.6 MPa to 1.3 MPa. This manufacturing method allows the production of a vehicle window glass 2 as shown in the lower diagram of FIG. 8 .

[0058] In the manufacturing method according to this embodiment, the cutout portion 17 of the functional component 15 is a gap before heating and pressing, as shown in the upper diagram of Fig. 8. Thereafter, by heating and pressing the laminate, the intermediate layer 13 melts and a portion of the intermediate layer 13 flows into the cutout portion 17, resulting in a vehicle window glass 2 having a configuration as shown in the lower diagram of Fig. 8.

[0059] At this time, the material of the intermediate layer 13 filled in the cutout portion 17 reaches the first glass sheet 11 and is bonded to the first glass sheet 11. This makes it possible to more effectively maintain the strength of the vehicle window glass 2. Note that the method for forming the vehicle window glass 2 is not limited to this method, and the vehicle window glass 2 may be formed using other manufacturing methods.

[0060] FIG. 9 is a plan view showing another example of the configuration of the functional member 15. In this embodiment, the outer edge of the dielectric layer 21 may have a portion that is positioned outward from the outer edge of the conductor layer 22. With this configuration, the dielectric layer 21 (TAC film) can be grasped and handled when positioning the functional member 15, making it easier to handle the functional member 15 during manufacturing. Note that in the functional member 15 shown in FIG. 9 , the cutout portion 17 is also a gap. Furthermore, the dielectric layer 21 that is positioned outward from the outer edge of the conductor layer 22 is transparent to visible light, thereby ensuring the occupant's field of vision.

[0061] Fig. 10 is a cross-sectional view showing another example of the configuration of a vehicle window glass according to an embodiment. In the vehicle window glass 2a shown in Fig. 10, an intermediate layer (second intermediate layer) 18 is disposed between the functional component 15 and the first glass plate 11. For example, the intermediate layer 18 may be made of the same material as the intermediate layer 13. If the intermediate layer 18 is made of the same material as the intermediate layer 13, the linear expansion coefficients are the same, which is preferable in that distortion due to temperature changes can be suppressed.

[0062] 10 is formed by laminating the first glass plate 11, the intermediate layer 18, the functional component 15, the intermediate layer 13, and the second glass plate 12 in this order. Then, by heating and pressurizing this laminate, the intermediate layers 13 and 18 melt, portions of the intermediate layers 13 and 18 flow into the cutout portion 17, and the intermediate layers 13 and 18 are bonded together, thereby forming the vehicle window glass 2a having the configuration shown in FIG.

[0063] For example, the thickness of the intermediate layer 13 disposed between the second glass plate 12 and the dielectric layer 21 and the thickness of the intermediate layer 18 disposed between the first glass plate 11 and the adhesive layer 23 may be configured to be approximately the same. Here, "approximately the same" means that the difference in thickness between the intermediate layers 13 and 18 is within a 10% range. The thickness of the intermediate layer 18, like the thickness of the intermediate layer 13, is preferably 0.50 mm or more, and more preferably 0.70 mm or more. The thickness of the intermediate layer 18 is preferably 1.10 mm or less.

[0064] Fig. 11 is a cross-sectional view showing another example of the configuration of a vehicle window glass according to an embodiment. The vehicle window glass 3 shown in Fig. 11 includes an antenna as a functional member 15, and the antenna includes a power supply electrode 31 and a ground electrode 32. The power supply electrode 31 and the ground electrode 32 are connected to a transmission line 43. The transmission line 43 is embedded in the intermediate layer 13 and is drawn out from the end between the first glass sheet 11 and the second glass sheet 12. While Fig. 11 shows a configuration in which the transmission line 43 is connected to the ground electrode 32, the power supply electrode 31 is connected to a separately provided transmission line (not shown). The cutout portion 17 is not shown in Fig. 11.

[0065] Fig. 12 is a cross-sectional view showing another example of the configuration of a vehicle window glass according to an embodiment. The vehicle window glass 4 shown in Fig. 12 includes an antenna as a functional member 15, and the antenna includes a power supply electrode 31 and a ground electrode 32. A power supply conductor 53 is disposed on the main surface of the second glass sheet 12 opposite the intermediate layer 13, facing the power supply electrode 31 in a plan view of the first glass sheet 11, and is capacitively coupled to the power supply electrode 31. A ground conductor 54 is disposed on the main surface of the second glass sheet 12 opposite the intermediate layer 13, and is capacitively coupled to the ground electrode 32. Although not shown in Fig. 12 , a transmission line is provided connecting the power supply conductor 53 and the ground conductor 54. Note that the cutout portion 17 is not shown in Fig. 12 .

[0066] Examples will be described below.

[0067] Example 1 As a sample according to Example 1, a vehicle window glass having the configuration shown in Fig. 2 was produced. Specifically, glass plates made of soda lime glass, each measuring 300 mm in length, 300 mm in width, and 2 mm in thickness, were prepared as the first glass plate 11 and the second glass plate 12. The soda lime glass contained 50% or less SiO, expressed in mole percentage based on the oxide of each component. ２ ≦80% 0.1%≦Al ２ O ３ ≦25% 3%≦R ２ O≦30% (R ２ O is Li ２ O, Na ２ O.K. ２ represents the total amount of O) 0%≦B ２ O３ ≦10% 0%≦MgO≦25% 0%≦CaO≦25% 0%≦SrO≦5% 0%≦BaO≦5% 0%≦ZrO ２ ≦5% 0%≦SnO ２ The material used was one that satisfied the condition of ≦5%.

[0068] A PVB film measuring 300 mm in length, 300 mm in width, and 0.76 mm in thickness was prepared as the intermediate layer 13. An antenna measuring 50 mm in length and 126 mm in width was prepared as the functional member 14. A TAC film with a thickness of 0.020 mm was used for the dielectric layer 21 of the functional member 14, copper foil with a thickness of 0.002 mm was used for the conductor layer 22, and OCA with a thickness of 0.025 mm was used for the adhesive layer 23. The line width of the conductor layer 22 was 1 mm, the horizontal pitch was 5 mm, and the vertical pitch was 4 mm.

[0069] Then, the first glass plate 11, the functional member 14, the intermediate layer 13, and the second glass plate 12 were laminated in this order, placed in a vacuum bag, and subjected to a heating and pressurizing treatment at a pressure of 1 MPa and a temperature of 110°C to produce a vehicle window glass according to Example 1. At this time, the functional member 14 was disposed in the center of the first glass plate 11 in a plan view of the first glass plate 11. The three samples according to Example 1 are respectively referred to as Examples 1-1 to 1-3 (Examples). Note that all of the samples according to Examples 1-1 to 1-3 were produced under the same conditions.

[0070] Example 2 A vehicle window glass 101 (comparative example) having the configuration shown in Fig. 13 was produced as a sample according to Example 2. The vehicle window glass 101 shown in Fig. 10 includes a first glass plate 111, an intermediate layer 113, a functional member 114, and a second glass plate 112. The functional member 114 includes a dielectric layer 121, a conductor layer 122, and an adhesive layer 123. In the sample according to Example 2, the adhesive layer 123 was in contact with the second glass plate 112.

[0071] Specifically, glass plates made of soda-lime glass (similar to Example 1) measuring 300 mm in length, 300 mm in width, and 2 mm in thickness were prepared as the first glass plate 111 and the second glass plate 112. A PVB film measuring 300 mm in length, 300 mm in width, and 0.76 mm in thickness was prepared as the intermediate layer 113. An antenna measuring 50 mm in length and 126 mm in width was prepared as the functional member 114. The dielectric layer 121 of the functional member 114 was made of a TAC film with a thickness of 0.020 mm, the conductor layer 122 was made of copper foil with a thickness of 0.002 mm, and the adhesive layer 123 was made of OCA with a thickness of 0.025 mm.

[0072] Then, the first glass plate 111, the intermediate layer 113, the functional member 114, and the second glass plate 112 were laminated in this order. This laminate was placed in a vacuum bag and subjected to a heating and pressurizing treatment at a pressure of 1 MPa and a temperature of 110°C, thereby producing a vehicle window glass according to Example 2. At this time, the functional member 114 was disposed in the center of the first glass plate 111 in a plan view of the first glass plate 111. The two samples according to Example 2 are respectively referred to as Examples 2-1 and 2-2 (comparative examples). Note that all of the samples according to Examples 2-1 and 2-2 were produced under the same conditions.

[0073] <Impact Resistance Test> An impact resistance test was conducted on the samples according to Examples 1 and 2. Specifically, each sample was stored at a temperature of -20°C for 4 hours. Thereafter, the sample was placed on a horizontally supported support frame with the first glass plate 11, 111 facing upward. An impact resistance test was then conducted by dropping a steel ball having a diameter of 38 mm and a weight of 227 g onto the sample from a height of 9 m. The sample was judged to have passed if the steel ball did not penetrate the sample and the total weight of the peeled pieces was 15 g or less.

[0074] <Test Results> The test results are shown in Table 1. As shown in Table 1, the total weight of the peeled pieces was 15 g or less for the samples in Examples 1-1 to 1-3, and all samples passed the test. On the other hand, the total weight of the peeled pieces was heavier than 15 g for the samples in Examples 2-1 to 2-2, and all samples failed. The reason that the samples in Examples 2-1 to 2-2 failed is thought to be that the adhesive strength of the adhesive layer 123 (OCA) decreased when the samples were stored at low temperatures. On the other hand, in the samples in Examples 1-1 to 1-3, the intermediate layer 13 (PVB) was bonded to the second glass plate 12, and therefore the strength of the vehicle window glass was thought to be maintained.

[0075]

[0076] 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.

[0077] This application claims priority based on Japanese Patent Application No. 2024-68896, filed April 22, 2024, the disclosure of which is incorporated herein in its entirety by reference.

[0078] DESCRIPTION OF SYMBOLS 1, 1a, 1b, 2, 2a, 3, 4 Vehicle window glass 11 First glass sheet 12 Second glass sheet 13 Intermediate layer (first intermediate layer) 14, 15 Functional member 16 Linear portion 17 Hole-out portion 18 Intermediate layer (second intermediate layer) 21 Dielectric layer 22 Conductor layer 23 Adhesive layer 31 Power supply electrode 32 Ground electrode 38 Rectangular area 43 Transmission line 53 Power supply conductor portion 54 Ground conductor portion

Claims

1. A vehicle window glass to be attached to an opening in a vehicle, the vehicle window glass comprising: a first glass plate arranged on the exterior side of the vehicle; a second glass plate arranged on the interior side of the vehicle; a first intermediate layer arranged between the first glass plate and the second glass plate; and a functional member arranged between the first glass plate and the second glass plate, wherein the functional member has a configuration in which a dielectric layer and a conductor layer are laminated, and the vehicle window glass includes a region in which the second glass plate, the first intermediate layer, the dielectric layer, and the conductor layer are laminated in this order.

2. The vehicle window glass according to claim 1, wherein the functional component further comprises an adhesive layer, and the vehicle window glass includes a region in which the second glass plate, the first intermediate layer, the dielectric layer, the conductor layer and the adhesive layer are laminated in this order.

3. The vehicle window glass according to claim 2, wherein the adhesive layer is in contact with the first glass sheet.

4. A vehicle window glass according to claim 2, wherein a second interlayer is disposed between the first glass sheet and the adhesive layer.

5. A vehicle window glass according to claim 4, wherein the thickness of the first intermediate layer disposed between the second glass sheet and the dielectric layer and the thickness of the second intermediate layer disposed between the first glass sheet and the adhesive layer are approximately the same.

6. A vehicle window glass as described in claim 2, wherein the conductor layer has, in a plan view, a linear portion and a first cutout portion that is surrounded by the linear portion and cut out in the thickness direction of the conductor layer.

7. A vehicle window glass according to claim 6, wherein the dielectric layer has a second cutout portion at a position that overlaps the first cutout portion of the conductor layer in a plan view.

8. A vehicle window glass as described in claim 7, wherein the adhesive layer has a third cutout portion at a position that overlaps the first cutout portion of the conductor layer and the second cutout portion of the dielectric layer in a plan view.

9. The vehicle window glass according to claim 8, wherein the first to third cutout portions of the functional member are filled with the material of the first intermediate layer.

10. A vehicle glazing according to claim 6, wherein the adhesive layer contacts the first glass sheet.

11. A vehicle glazing as claimed in claim 6, wherein a second interlayer is disposed between the first glass pane and the adhesive layer.

12. The vehicle window glass according to claim 11, wherein the thickness of the first intermediate layer disposed between the second glass sheet and the dielectric layer and the thickness of the second intermediate layer disposed between the first glass sheet and the adhesive layer are approximately the same.

13. A vehicle glazing as claimed in claim 1 or 2, wherein the conductor layer is a flat conductor having slots formed therein.

14. A vehicle window glass according to claim 1 or 2, wherein the functional component is an antenna capable of transmitting and receiving radio waves of a predetermined frequency.

15. The vehicle window glass according to claim 14, wherein the antenna comprises a feeding electrode and a ground electrode on the conductor layer.

Images