JP7444830B2 - windshield - Google Patents

Description

The present invention relates to a windshield in which an information acquisition device that acquires information from outside a vehicle by emitting and/or receiving light can be placed thereon, and a method for manufacturing the windshield.

In recent years, the safety performance of automobiles has been improving dramatically, and one of the improvements is to detect the distance to the vehicle in front and the speed of the vehicle in front, and to automatically detect when the vehicle approaches abnormally. A safety system in which a brake is activated has been proposed. Such systems use laser radar and cameras to measure the distance to the vehicle in front. Laser radars and cameras are generally placed inside a windshield and perform measurements by emitting light such as infrared rays forward (for example, Patent Document 1).

Japanese Patent Application Publication No. 2006-96331

As described above, measurement devices such as laser radar and cameras are placed on the inner surface of the glass plate that constitutes the windshield, and emit and receive light through the glass plate. However, on days with low temperatures or in cold regions, the glass plate may fog up. However, if the glass plate becomes cloudy, there is a risk that the measuring device may not be able to accurately irradiate or receive light. As a result, there is a possibility that the distance between vehicles and the like may not be calculated accurately.

Such a problem is not limited to inter-vehicle distance measuring devices, but can occur in general information acquisition devices that acquire information from outside the vehicle by receiving light, such as rain sensors, light sensors, and optical beacons. The present invention was made in order to solve the above problem, and is a windshield to which an information acquisition device that emits and/or receives light through a glass plate can be attached. It is an object of the present invention to provide a windshield and a method for manufacturing the same, which can be performed accurately and information can be processed accurately.

The windshield according to the present invention is a windshield in which an information acquisition device that acquires information from outside the vehicle by irradiating and/or receiving light can be placed, and includes a glass plate and a barrier provided on the glass plate. fogging means, the glass plate has at least one information acquisition area facing the information acquisition device and through which the light passes, and the antifogging means includes at least It is provided to prevent fogging of the information acquisition area.

In the above windshield, the anti-fog means may be an anti-fog film, and the anti-fog film may be disposed at least in the information acquisition area of the glass plate.

The anti-fogging film can be formed by applying a liquid agent on the glass plate at a location corresponding to the information acquisition area.

The antifogging film may contain inorganic oxide particles to form irregularities on the surface.

The refractive index of the antifogging film may be greater than the refractive index of air and smaller than the refractive index of the glass plate.

The antifogging film may have an organic substance containing a water-absorbing resin as a main component.

The anti-fog film can be formed in a film shape including a base layer and an anti-fog functional layer formed on the base layer, and is arranged in a manner corresponding to the information acquisition area on the glass plate. It can be configured to be pasted.

The antifogging functional layer can have a main component of a water-absorbing resin or a substance having a hydrophilic group and exhibiting hydrophilic properties on the surface of the film.

The anti-fog functional layer may contain inorganic oxide particles to form irregularities on the surface.

The refractive index of the anti-fogging functional layer can be made larger than the refractive index of air and smaller than the refractive index of the glass plate.

The anti-fogging means may include a heating wire to which a current is applied, and the heating wire may be disposed at least in the information acquisition area.

The heating wire can be connected in series to a power source.

At least a portion of each heating wire may have a line width of 0.05 to 0.5 mm at least at a portion passing through the information acquisition area.

In the heating wire, at least one of the surface facing the glass plate and the surface facing the inside of the vehicle may be coated with a coating material.

The coating may be a dark ceramic.

The above-mentioned anti-fogging means can be composed of a plurality of means.

For example, the anti-fog means may include at least an anti-fog film disposed on the vehicle-inward surface of the glass plate and a heating wire to which an electric current is applied.

Alternatively, the anti-fog means includes at least an anti-fog film disposed on the vehicle side surface of the glass plate, and a transparent conductive film disposed between the anti-fog film and the glass plate;
It can be composed of

In each of the above windshields, the information acquisition device may include a stereo camera having a plurality of photographing devices spaced apart from each other so as to be able to acquire a plurality of images with parallax, and the plurality of information acquisition regions are It can be provided so as to correspond to each photographing device.

In each of the windshields described above, the information acquisition device can include a bracket for attaching the information acquisition device to the glass plate, and the information acquisition area can be configured to be surrounded by the bracket.

A method for manufacturing a windshield according to the present invention is a method for manufacturing a windshield in which an information acquisition device that acquires information from outside the vehicle by irradiating and/or receiving light can be arranged, the method comprising: forming a glass plate having at least one information acquisition area facing each other through which the light passes; preparing a transfer sheet on which at least heating wires are arranged; and connecting the heating wires from the transfer sheet to the glass plate. and a step of transferring the information to the information acquisition area on the inner surface.

According to the present invention, in a windshield to which an information acquisition device that emits and/or receives light through a glass plate can be attached, it is possible to accurately emit and/or receive light, and to process information. Can be done accurately.

1 is a cross-sectional view of one embodiment of a windshield according to the present invention. FIG. 2 is a plan view of FIG. 1; It is a sectional view of laminated glass. It is a front view (a) and sectional view (b) which show the amount of overlap of curved laminated glass. , is a graph showing a general relationship between frequency and sound transmission loss for a curved glass plate and a planar glass plate. It is a schematic plan view showing the measurement position of the thickness of laminated glass. This is an example of an image used for measuring an interlayer film. It is a top view of a glass plate. FIG. 3 is an enlarged plan view of a center mask layer. FIG. 9 is a sectional view taken along line AA in FIG. 9; It is a side view showing an example of the manufacturing method of a glass plate. FIG. 3 is a plan view of parts constituting the measurement unit. FIG. 3 is a cross-sectional view of the sensor. It is a figure showing an example of the effect of an antifogging film. It is a figure explaining the antireflection effect by an antifogging film. It is a figure explaining the antireflection effect by an antifogging film. FIG. 3 is a plan view showing an example in which the antifogging means according to the present invention is configured by a heating wire. It is a sectional view showing an example of a transfer sheet. 19 is a cross-sectional view showing an example of a method of transferring heating wires using the transfer sheet of FIG. 18. FIG. FIG. 7 is a plan view showing another example in which the antifogging means according to the present invention is configured by a heating wire. FIG. 3 is a partial cross-sectional view of a windshield showing an example in which an anti-fog film and a heating wire are arranged. FIG. 2 is a partial cross-sectional view of a windshield showing an example in which an anti-fog film, a transparent conductive film, and a heating wire are arranged. FIG. 2 is a front view showing an example of a windshield provided with a stereo camera. FIG. 24 is a cross-sectional view of FIG. 23;

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention in which an inter-vehicle distance measuring unit is attached to a windshield will be described below with reference to the drawings. FIG. 1 is a sectional view of a windshield according to this embodiment, and FIG. 2 is a plan view of FIG. 1. As shown in FIGS. 1, 2, 8, and 9, the windshield according to the present embodiment includes a glass plate 1 and a mask layer 2 formed on the surface of the glass plate 1 on the inside of the vehicle. A measurement unit 4 for measuring the inter-vehicle distance is attached to the mask layer 2. Furthermore, openings 231 and 232 are formed in the mask layer 2, and the measurement unit 4 irradiates light and receives light through these openings 231 and 232. An anti-fog film is formed on the inner surface of the glass plate 1 in areas corresponding to the openings 231 and 232 of the mask layer 2. Each member will be explained below.

<1. Glass plate＞
<1-1. Composition of glass plate/composition of laminated glass＞
The glass plate 1 can have various configurations, for example, it can be composed of laminated glass having a plurality of glass plates, or it can be composed of a single glass plate. When laminated glass is used, it can be configured as shown in FIG. 3, for example. FIG. 3 is a cross-sectional view of the laminated glass.

As shown in the figure, this laminated glass 1 includes an outer glass plate 11 and an inner glass plate 12, and a resin intermediate film 13 is disposed between these glass plates 11 and 12. First, the outer glass plate 11 and the inner glass plate 12 will be explained. For the outer glass plate 11 and the inner glass plate 12, known glass plates can be used, and they can also be formed of heat ray absorbing glass, general clear glass, green glass, or UV green glass. However, these glass plates 11 and 12 need to realize visible light transmittance that meets the safety standards of the country where the automobile is used. For example, the outer glass plate 11 can ensure the necessary solar absorption rate, and the inner glass plate 12 can adjust the visible light transmittance to meet safety standards. Examples of clear glass, heat ray absorbing glass, and soda lime glass are shown below.

(clear glass)
SiO ₂ :70-73% by mass
Al ₂ O ₃ :0.6-2.4% by mass
CaO: 7-12% by mass
MgO: 1.0 to 4.5% by mass
R ₂ O: 13 to 15% by mass (R is an alkali metal)
Total iron oxide (T-Fe ₂ O ₃ ) converted to Fe ₂ O ₃ : 0.08 to 0.14% by mass

(heat ray absorbing glass)
The composition of the heat ray absorbing glass is, for example, based on the composition of clear glass, the ratio of total iron oxide (T-Fe ₂ O ₃ ) converted to Fe ₂ O ₃ is 0.4 to 1.3% by mass, and CeO The ratio of ₂ to 0
2% by mass, the ratio of TiO ₂ is 0 to 0.5% by mass, and the glass skeleton components (mainly S
The composition can be made such that the amount of (iO ₂ or Al ₂ O ₃ ) is decreased by the amount of T--Fe ₂ O ₃ , CeO ₂ and TiO ₂ .

(soda lime glass)
SiO ₂ :65-80% by mass
Al ₂ O ₃ : 0 to 5% by mass
CaO: 5-15% by mass
MgO: 2% by mass or more NaO: 10-18% by mass
K ₂ O: 0 to 5% by mass
MgO+CaO: 5-15% by mass
Na ₂ O + K ₂ O: 10-20% by mass
SO ₃ :0.05-0.3% by mass
B ₂ O ₃ : 0 to 5% by mass
Total iron oxide (T-Fe ₂ O ₃ ) converted to Fe ₂ O ₃ : 0.02 to 0.03% by mass

The thickness of the laminated glass according to this embodiment is not particularly limited, but from the viewpoint of weight reduction, the total thickness of the outer glass plate 11 and the inner glass plate 12 is preferably 2.4 to 5.0 mm. , more preferably from 2.6 to 4.6 mm, particularly preferably from 2.7 to 3.2 mm. In this way, in order to reduce the weight, it is necessary to reduce the total thickness of the outer glass plate 11 and the inner glass plate 12, so the thickness of each glass plate is not particularly limited, but For example, the thicknesses of the outer glass plate 11 and the inner glass plate 12 can be determined as follows.

The outer glass plate 11 mainly needs to have durability and impact resistance against external obstacles. For example, when this laminated glass is used as a windshield for a car, it must have impact resistance against flying objects such as pebbles. is necessary. On the other hand, the greater the thickness, the greater the weight, which is undesirable. From this point of view, the thickness of the outer glass plate 11 is preferably 1.8 to 2.3 mm, more preferably 1.9 to 2.1 mm. Which thickness to adopt can be determined depending on the use of the glass.

The thickness of the inner glass plate 12 can be made equal to that of the outer glass plate 11, but can be made smaller than the thickness of the outer glass plate 11, for example, in order to reduce the weight of the laminated glass. Specifically, considering the strength of the glass, it is preferably 0.6 to 2.3 mm, preferably 0.8 to 2.0 mm, and particularly preferably 1.0 to 1.4 mm. preferable. Furthermore, it is preferably 0.8 to 1.3 mm. The thickness to be adopted for the inner glass plate 12 can also be determined depending on the use of the glass.

Moreover, the shape of the outer glass plate 11 and the inner glass plate 12 according to this embodiment may be either a planar shape or a curved shape.

When the glass plate has a curved shape, it is said that as the amount of overlap increases, the sound insulation performance deteriorates. The amount of overlap is the amount that indicates the bending of the glass plate. For example, when a straight line L connecting the center of the upper side of the glass plate and the center of the lower side is set as shown in FIG. The largest distance between the two is defined as the amount of overlap D.

FIG. 5 is a graph showing a general relationship between frequency and sound transmission loss for a curved glass plate and a planar glass plate. According to Figure 5, the curved glass plate has no significant difference in sound transmission loss in the overlap amount range of 30 to 38 mm, but compared to the flat glass plate, the sound transmission loss is lower in the frequency band below 4000 Hz. It can be seen that the loss is decreasing. Therefore, when producing a curved glass plate, it is better to have a smaller amount of overlap. For example, if the amount of overlap exceeds 30 mm, the Young's modulus of the core layer of the interlayer film should be set to 18 MPa (frequency 100Hz, temperature 20°C) or less.

Here, an example of a method for measuring the thickness when the glass plate (laminated glass) 1 is curved will be described. First, as shown in FIG. 6, the measurement positions are two locations above and below a center line S extending vertically from the center of the glass plate in the left-right direction. The measuring device is not particularly limited, but for example, a thickness gauge such as SM-112 manufactured by Techlock Co., Ltd. can be used. At the time of measurement, the curved surface of the glass plate is placed on a flat surface, and the edge of the glass plate is held between the thickness gauges and measured. Note that even if the glass plate is flat, it can be measured in the same way as when it is curved.

<1-2. Laminated glass interlayer film>
The intermediate film 13 is formed of at least one layer, and as an example, as shown in FIG. 3, it can be formed of three layers in which a soft core layer 131 is sandwiched between harder outer layers 132. However, the structure is not limited to this, and may be formed of a plurality of layers including the core layer 131 and at least one outer layer 132 disposed on the outer glass plate 11 side. For example, a two-layer intermediate film 13 including a core layer 131 and one outer layer 132 disposed on the outer glass plate 11 side, or an even number of outer layers 132 of two or more layers on each side centering on the core layer 131. Alternatively, the intermediate film 13 may be an intermediate film 13 in which an odd number of outer layers 132 are arranged on one side and an even number of outer layers 132 are arranged on the other side with the core layer 131 interposed therebetween. Note that when only one outer layer 132 is provided, it is provided on the outer glass plate 11 side as described above, but this is to improve breakage resistance against external forces from outside the vehicle or outdoors. Moreover, if the number of outer layers 132 is large, the sound insulation performance will also be high.

As long as the core layer 131 is softer than the outer layer 132, its hardness is not particularly limited. The materials constituting each layer 131, 132 are not particularly limited, but can be selected based on Young's modulus, for example. Specifically, at a frequency of 100 Hz and a temperature of 20 degrees, it is preferably 1 to 20 MPa, more preferably 1 to 18 MPa, and particularly preferably 1 to 14 MPa. With this range, it is possible to prevent the STL from decreasing in the low frequency range of approximately 3500 Hz or less. On the other hand, as will be described later, the Young's modulus of the outer layer 132 is preferably large in order to improve sound insulation performance in a high frequency range, and is preferably 560 MPa or more, 600 MPa or more, 650 MPa or more, 700 MPa or more at a frequency of 100 Hz and a temperature of 20 degrees. It can be 750 MPa or more, 880 MPa or more, or 1300 MPa or more. On the other hand, the upper limit of the Young's modulus of the outer layer 132 is not particularly limited, but can be set from the viewpoint of processability, for example. For example, it is empirically known that when the pressure exceeds 1750 MPa, workability, particularly cutting, becomes difficult.

Further, as a specific material, the outer layer 132 can be made of, for example, polyvinyl butyral resin (PVB). Polyvinyl butyral resin is preferable because it has excellent adhesion to each glass plate and penetration resistance. On the other hand, the core layer 131 can be made of, for example, ethylene vinyl acetate resin (EVA) or a polyvinyl acetal resin that is softer than the polyvinyl butyral resin that constitutes the outer layer. By sandwiching a soft core layer between them, it is possible to significantly improve sound insulation performance while maintaining adhesiveness and penetration resistance equivalent to those of a single-layer resin interlayer film.

Generally, the hardness of polyvinyl acetal resin can be controlled by (a) degree of polymerization of polyvinyl alcohol as a starting material, (b) degree of acetalization, (c) type of plasticizer, (d) addition ratio of plasticizer, etc. I can do it. Therefore, by appropriately adjusting at least one selected from these conditions, even if the same polyvinyl butyral resin is used, a hard polyvinyl butyral resin used for the outer layer 132 and a soft polyvinyl butyral resin used for the core layer 131 can be changed. It is possible to make them separately. Furthermore, the hardness of the polyvinyl acetal resin can also be controlled by the type of aldehyde used for acetalization, coacetalization using multiple types of aldehydes, or pure acetalization using a single type of aldehyde. Although it cannot be generalized, polyvinyl acetal resins obtained using aldehydes with a larger number of carbon atoms tend to be softer. Therefore, for example, when the outer layer 132 is made of polyvinyl butyral resin, the core layer 131 may contain an aldehyde having 5 or more carbon atoms (for example, n-hexylaldehyde, 2-ethylbutyraldehyde, n-heptylaldehyde, A polyvinyl acetal resin obtained by acetalizing n-octylaldehyde) with polyvinyl alcohol can be used. In addition, if a predetermined Young's modulus can be obtained, the resin is not limited to the above resins.

Further, the total thickness of the intermediate film 13 is not particularly defined, but is preferably 0.3 to 6.0 mm, more preferably 0.5 to 4.0 mm, and 0.6 to 2.0 mm. It is particularly preferable that there be. Further, the thickness of the core layer 131 is preferably 0.1 to 2.0 mm, more preferably 0.1 to 0.6 mm. On the other hand, the thickness of each outer layer 132 is preferably 0.1 to 2.0 mm, more preferably 0.1 to 1.0 mm. Alternatively, the total thickness of the intermediate film 13 may be kept constant, and the thickness of the core layer 131 may be adjusted within this.

The thickness of the core layer 131 and the outer layer 132 can be measured, for example, as follows. First, a cross section of the laminated glass is enlarged 175 times and displayed using a microscope (for example, VH-5500 manufactured by Keyence Corporation). Then, the thicknesses of the core layer 131 and the outer layer 132 are visually identified and measured. At this time, in order to eliminate visual variations, the number of measurements was made five times, and the average value was taken as the thickness of the core layer 131 and the outer layer 132. For example, an enlarged photograph of a laminated glass as shown in FIG. 7 is taken, and the core layer and outer layer 132 are identified and their thicknesses are measured.

Note that the thicknesses of the core layer 131 and the outer layer 132 of the intermediate film 13 do not need to be constant over the entire surface, and may be wedge-shaped for laminated glass used in head-up displays, for example. In this case, the thickness of the core layer 131 and the outer layer 132 of the interlayer film 13 is measured at the point where the thickness is the smallest, that is, at the lowest side of the laminated glass. When the intermediate film 13 is wedge-shaped, the outer glass plate and the inner glass plate are not arranged in parallel, but such an arrangement is also included in the glass plate according to the present invention. That is, the present invention includes, for example, the arrangement of the outer glass plate and the inner glass plate when using the intermediate film 13 using the core layer 131 and the outer layer 132 whose thickness increases at a rate of change of 3 mm or less per 1 m. .

The method for producing the interlayer film 13 is not particularly limited, but for example, a resin component such as the above-mentioned polyvinyl acetal resin, a plasticizer, and other additives as necessary are mixed, uniformly kneaded, and then each layer is combined at once. Examples include a method of extrusion molding, and a method of laminating two or more resin films created by this method by a pressing method, a laminating method, or the like. The resin film before lamination used in a laminating method such as a pressing method or a laminating method may have a single-layer structure or a multi-layer structure. Further, the intermediate film 13 can be formed of a single layer instead of the plurality of layers as described above.

<1-3. Infrared transmittance of glass plate＞
As described above, the windshield according to the present embodiment is used for a forward safety system of an automobile using a measurement unit such as a laser radar or a camera. Such safety systems measure the speed and distance between vehicles in front by emitting infrared light to the vehicle in front. Therefore, laminated glass (or a single glass plate) is required to achieve infrared transmittance within a predetermined range.

For example, when using a general sensor for laser radar, the transmittance is 20% or more and 80% or less, or at least 20% or more and 60% or less for light with a wavelength of 850 to 950 nm (infrared rays). It is said that certain things are useful. The method for measuring transmittance is in accordance with JIS R3106, and UV3100 (manufactured by Shimadzu Corporation) can be used as a measuring device. Specifically, the transmission of light in one direction, which is irradiated onto the surface of the laminated glass at an angle of 90 degrees, is measured.

In addition, some of the safety systems mentioned above do not use laser radar, but instead use infrared cameras to measure the speed of the vehicle ahead and the distance between vehicles. When using, it is said to be useful that it is 30% or more and 80% or less, preferably 40% or more and 60% or less, for light having a wavelength of 700 to 800 nm (infrared rays). The transmittance measurement method follows ISO9050.

<2. Mask layer>
Next, the mask layer 2 will be explained. A mask layer 2 as shown in FIG. 8 is formed on the glass plate 1 according to this embodiment. The mask layer 2 is laminated on the glass plate, but its position is not particularly limited. For example, if the glass plate is formed of a single glass plate, the mask layer 2 can be laminated on the inside surface of the vehicle. On the other hand, when the glass plates are made of laminated glass as shown in FIG. At least one of the surfaces can be laminated. In this case, for example, if the mask layer 2 having approximately the same shape is formed on both the vehicle inner side surface of the outer glass plate 11 and the vehicle inner side surface of the inner glass plate 12, the mask layer 2 is laminated at a location where the mask layer 2 is laminated. This is preferable because the curvatures of both glass plates 11 and 12 match. Note that FIG. 1 shows an example in which the mask layer 2 is formed on the inner surface of the glass plate 1.

This mask layer 2 is a dark-colored area formed on the outer periphery of the glass plate 1 to make it invisible from the outside, such as by applying adhesive when attaching the glass plate 1 to the vehicle body. It includes a peripheral mask layer 21 and a center mask layer 22 extending downward from the center of the upper edge of the glass plate 1 in the peripheral mask layer 21 . The measurement unit 4 described above is attached to the center mask layer 22. The measurement unit 4 may be arranged to such an extent that the light emitted from the sensor 5 passes through the center of the aperture (information acquisition area) and can receive reflected light from the preceding vehicle and obstacles, as will be described later. These mask layers 2 can be formed of various materials, but are not particularly limited as long as they can block the view from outside the vehicle. For example, the mask layer 2 may be formed of a dark-colored ceramic such as black, which is coated on the glass plate 1. It can be formed by

Next, the center mask layer 22 will be explained. As shown in FIG. 9, the center mask layer 22 is formed in a rectangular shape extending in the vertical direction, and has two openings aligned in the vertical direction, that is, an upper opening 231 and a lower opening 232. Both the upper opening 231 and the lower opening 232 are formed in a trapezoidal shape, but the width of the lower opening 232 in the left-right direction is about half the width of the upper opening 231. However, the lengths in the vertical direction are approximately the same. The sizes of the openings are not particularly limited, but for example, the upper opening 231 can be about 58 mm long and about 58 mm wide, and the lower opening 232 can be about 52 mm long and about 27 mm wide.

The center mask layer 22 is divided into three regions: an upper region 221 above the upper opening 231, a lower region 222 below the upper region 221 and including both openings 231 and 232, and a side of the lower region 222. It is composed of a small rectangular side region 223 formed in the section.

Next, the layer structure of each region will be explained. As shown in FIG. 10, the upper region 221 is formed of a single layer of a first ceramic layer 241 made of black ceramic. The lower region 222 is formed of three layers, the first ceramic layer 241, the silver layer 242, and the second ceramic layer 243, which are laminated from the inner surface of the glass plate 1. The silver layer 242 is made of silver, and the second ceramic layer 243 is made of the same material as the first ceramic layer 241. Further, the side region 223 is formed of two layers, a first ceramic layer 241 and a silver layer 242, which are laminated from the inner surface of the glass plate 1, and the silver layer 242 is exposed to the inside of the vehicle. The lowermost first ceramic layer 241 is common to each region, and the second silver layer 242 is common to the lower region 222 and side region 223. Note that in order to ensure light-shielding properties, the thickness of each ceramic layer 241, 243 can be set to, for example, 10 to 20 μm. In addition, as will be described later, the bracket of the measuring unit 4 is bonded to the center mask layer 22 formed on the vehicle-inward side surface of the inner glass plate 12 with an adhesive, so this is also used to ensure adhesiveness. The thickness is preferably as follows. This is because, for example, urethane/silicon adhesives may be deteriorated by ultraviolet rays.

The peripheral mask layer 21 and the center mask layer 22 can be formed, for example, as follows. First, a first ceramic layer 241 is applied on a glass plate. This first ceramic layer 241 is common to the peripheral mask layer 21 . Next, a silver layer 242 is applied on the first ceramic layer 241 in regions corresponding to the lower region 222 and the side regions 223 . Finally, a second ceramic layer 243 is applied to a region corresponding to the lower region 222. In addition, in the lower region 222, the region where the silver layer 242 is formed corresponds to a position where a sensor of the measurement unit 4, which will be described later, is arranged. Further, the silver layer 242 exposed in the side region 223 is provided with grounding wiring. The ceramic layers 241, 243 and the silver layer 242 can be formed by a screen printing method, but they can also be formed by transferring a firing transfer film onto a glass plate and firing it.

The ceramic layers 241 and 243 can be formed of various materials, and may have the following compositions, for example.

Further, the silver layer 242 is also not particularly limited, but may have the following composition, for example.

Screen printing conditions can be, for example, polyester screen: 355 mesh, coat thickness: 20 μm, tension: 20 Nm, squeegee hardness: 80 degrees, installation angle: 75 degrees, printing speed: 300 mm/s, and drying oven. By drying at 150° C. for 10 minutes, a ceramic layer and a silver layer can be formed. Note that when the first ceramic layer 241, silver layer 242, and second ceramic layer 243 are laminated in this order, the screen printing and drying described above may be repeated.

<3. Anti-fog film>
The antifogging film will be explained below. The anti-fog film is not particularly limited as long as it has an anti-fog effect on the glass plate 1, and any known film can be used. In general, there are three types of anti-fog films: a hydrophilic type that forms a water film on the surface of water generated from water vapor, a water-absorbing type that absorbs water vapor, and a water-repellent type that repels water droplets generated from water vapor. An anti-fog film is also applicable. Below, as an example, an example of a water-absorbing type anti-fog film will be described.
[Organic-inorganic composite anti-fog film]
The organic-inorganic composite antifogging film is a single layer film or a laminated multilayer film formed on the surface of a glass plate. The organic-inorganic composite antifogging film contains an organic substance and an inorganic oxide. The organic substance includes a water-absorbing resin, and the inorganic oxide includes a silica component. The organic-inorganic composite antifogging film may contain an ultraviolet absorber and/or an infrared absorber. Each component will be explained below.

(Water absorbent resin)
There are no particular restrictions on the water-absorbing resin, and examples include polyethylene glycol, polyether resin, polyurethane resin, starch resin, cellulose resin, acrylic resin, epoxy resin, polyester polyol, hydroxyalkyl cellulose, polyvinyl alcohol, polyvinylpyrrolidone, Examples include polyvinyl acetal resin and polyvinyl acetate. Among these, preferred are hydroxyalkylcellulose, polyvinyl alcohol, polyvinylpyrrolidone, polyvinyl acetal resin, polyvinyl acetate, epoxy resin, and polyurethane resin, and more preferred are polyvinyl acetal resin, epoxy resin, and polyurethane resin. Among them, polyvinyl acetal resin is particularly preferred.

Polyvinyl acetal resin can be obtained by subjecting polyvinyl alcohol to a condensation reaction with aldehyde to acetalize it. Acetalization of polyvinyl alcohol may be carried out using a known method such as a precipitation method using an aqueous medium in the presence of an acid catalyst or a dissolution method using a solvent such as alcohol. Acetalization can also be carried out in parallel with saponification of polyvinyl acetate. The degree of acetalization is preferably 2 to 40 mol%, more preferably 3 to 30 mol%, particularly 5 to 20 mol%, and in some cases 5 to 15 mol%. The degree of acetalization can be measured, for example, based on ¹³ C nuclear magnetic resonance spectroscopy. A polyvinyl acetal resin having a degree of acetalization within the above range is suitable for forming an organic-inorganic composite antifogging film having good water absorption and water resistance.

The average degree of polymerization of polyvinyl alcohol is preferably 200 to 4,500, more preferably 500 to 4,500. A high average degree of polymerization is advantageous for forming an organic-inorganic composite antifogging film with good water absorption and water resistance, but if the average degree of polymerization is too high, the viscosity of the solution becomes too high, which may hinder the formation of the film. Something may happen. The saponification degree of polyvinyl alcohol is preferably 75 to 99.8 mol%.

Examples of the aldehyde to be subjected to the condensation reaction with polyvinyl alcohol include aliphatic aldehydes such as formaldehyde, acetaldehyde, butyraldehyde, hexylcarbaldehyde, octylcarbaldehyde, and decylcarbaldehyde. Also, benzaldehyde; 2-methylbenzaldehyde, 3-methylbenzaldehyde, 4-methylbenzaldehyde, other alkyl group-substituted benzaldehydes; chlorobenzaldehyde, other halogen atom-substituted benzaldehydes; alkyl groups such as hydroxy groups, alkoxy groups, amino groups, cyano groups, etc. Examples include substituted benzaldehydes in which hydrogen atoms are substituted with functional groups other than groups; aromatic aldehydes such as fused aromatic ring aldehydes such as naphthaldehyde and anthraldehyde. Aromatic aldehydes with strong hydrophobicity are advantageous in forming an organic-inorganic composite antifogging film with a low degree of acetalization and excellent water resistance. The use of aromatic aldehydes is also advantageous in forming a membrane with high water absorption while leaving a large amount of hydroxyl groups. The polyvinyl acetal resin preferably contains an acetal structure derived from an aromatic aldehyde, particularly benzaldehyde.

Examples of the epoxy resin include glycidyl ether epoxy resin, glycidyl ester epoxy resin, glycidylamine epoxy resin, and cycloaliphatic epoxy resin. Among these, preferred are cycloaliphatic epoxy resins.

Examples of the polyurethane resin include polyurethane resins composed of polyisocyanate and polyol. As the polyol, acrylic polyols and polyoxyalkylene polyols are preferred.

The organic-inorganic composite antifogging film has a water-absorbing resin as its main component. In the present invention, the term "main component" means a component having the highest content on a mass basis. The content of the water-absorbing resin based on the weight of the organic-inorganic composite antifogging film is preferably 50% by weight or more, more preferably 60% by weight or more, particularly preferably 65% by weight, from the viewpoint of film hardness, water absorption, and antifogging properties. The content is 95% by weight or less, more preferably 90% by weight or less, particularly preferably 85% by weight or less.

(Inorganic oxide)
The inorganic oxide is, for example, an oxide of at least one element selected from Si, Ti, Zr, Ta, Nb, Nd, La, Ce, and Sn, and includes at least an oxide of Si (silica). The amount of the organic-inorganic composite antifogging film is preferably 0.01 parts by weight or more, more preferably 0.1 parts by weight or more, still more preferably 0.2 parts by weight or more, and particularly preferably is 1 part by weight or more, most preferably 5 parts by weight or more, in some cases 10 parts by weight or more, if necessary 20 parts by weight or more, and preferably 50 parts by weight or less, more preferably 45 parts by weight or less, even more preferably The inorganic oxide is preferably contained in an amount of 40 parts by weight or less, particularly preferably 35 parts by weight or less, most preferably 33 parts by weight or less, and in some cases, 30 parts by weight or less. Inorganic oxides are necessary components to ensure the strength, especially wear resistance, of organic-inorganic composite anti-fog films, but when their content increases, the anti-fog properties of organic-inorganic composite anti-fog films decrease. .

(Inorganic oxide fine particles)
The organic-inorganic composite antifogging film may further contain inorganic oxide fine particles as at least a part of the inorganic oxide. The inorganic oxide constituting the inorganic oxide fine particles is, for example, an oxide of at least one element selected from Si, Ti, Zr, Ta, Nb, Nd, La, Ce, and Sn, and is preferably silica fine particles. be. Silica fine particles can be introduced into the organic-inorganic composite antifogging film by, for example, adding colloidal silica. The inorganic oxide fine particles have an excellent effect of transmitting stress applied to the organic-inorganic composite anti-fog film to an article supporting the organic-inorganic composite anti-fog film, and have high hardness. Therefore, the addition of inorganic oxide fine particles is advantageous from the viewpoint of improving the abrasion resistance of the organic-inorganic composite antifogging film. Furthermore, when inorganic oxide fine particles are added to an organic-inorganic composite antifogging film, fine voids are formed in areas where the fine particles are in contact with or are close to each other, and water vapor is easily taken into the film through these voids. Therefore, the addition of inorganic oxide fine particles may have an advantageous effect on improving antifogging properties. The inorganic oxide fine particles can be supplied to the organic-inorganic composite antifogging film by adding previously formed inorganic oxide fine particles to the coating liquid for forming the organic-inorganic composite antifogging film.

If the average particle size of the inorganic oxide fine particles is too large, the organic-inorganic composite antifogging film may become cloudy, and if it is too small, they aggregate and become difficult to disperse uniformly. From this point of view, the average particle size of the inorganic oxide fine particles is preferably 1 to 20 nm, more preferably 5 to 20 nm. Note that here, the average particle size of the inorganic oxide fine particles is described in the state of primary particles. Further, the average particle size of the inorganic oxide fine particles is determined by measuring the particle size of 50 arbitrarily selected fine particles by observation using a scanning electron microscope, and employing the average value thereof. When the content of the inorganic oxide fine particles increases, the water absorption amount of the entire organic-inorganic composite anti-fog film may decrease, and the organic-inorganic composite anti-fog film may become cloudy. The inorganic oxide fine particles are preferably used in an amount of 0 to 50 parts by weight, more preferably 2 to 30 parts by weight, even more preferably 5 to 25 parts by weight, and particularly preferably 10 to 20 parts by weight based on 100 parts by weight of the water absorbent resin. It is advisable to add it so that the amount of

(Hydrolyzable metal compound)
In order to incorporate an inorganic oxide into an organic-inorganic composite anti-fogging film, a metal compound having a hydrolyzable group (hydrolyzable metal compound) or its hydrolyzate is added to the organic-inorganic composite anti-fogging film. It is recommended to add it to the coating solution. As the hydrolyzable metal compound, a silicon compound having a hydrolyzable group represented by the following formula (I) is preferable. The silica contained in the inorganic oxide preferably includes silica derived from a silicon compound having a hydrolyzable group or a hydrolyzate thereof. The silicon compound having a hydrolyzable group represented by formula (I) may be used alone or in combination of two or more. In the present invention, among silicon compounds bonded by siloxane bonds, those in which an organic metal is directly bonded to a part of the silicon are also included in silica.

R _m SiX _4-m (I)
R in formula (I) is a hydrocarbon group having 1 to 3 carbon atoms, the hydrogen atom of which may be substituted with a reactive functional group. Examples of hydrocarbon groups having 1 to 3 carbon atoms include alkyl groups having 1 to 3 carbon atoms (methyl group, ethyl group, n-propyl group, isopropyl group) and alkenyl groups having 2 to 3 carbon atoms (vinyl group, allyl group). , propenyl group), etc.

The reactive functional group is preferably at least one selected from oxyglycidyl groups and amino groups. The hydrolyzable metal compound with a reactive functional group firmly bonds the water-absorbing resin, which is an organic substance, with the silica, which is an inorganic oxide, and contributes to improving the abrasion resistance, hardness, etc. of the organic-inorganic composite antifogging film. It is possible.

X in formula (I) is a hydrolyzable group or a halogen atom. Examples of the hydrolyzable group include at least one selected from an alkoxyl group, an acetoxy group, an alkenyloxy group, and an amino group. Examples of the alkoxyl group include alkoxyl groups having 1 to 4 carbon atoms (methoxy group, ethoxy group, propoxy group, butoxy group), and the like. Among the hydrolyzable groups, preferred are alkoxyl groups, and more preferred are alkoxyl groups having 1 to 4 carbon atoms. The halogen atom is, for example, chlorine.

m in formula (I) is an integer of 0 to 2, preferably an integer of 0 to 1.

A preferred specific example of the silicon compound having a hydrolyzable group represented by formula (I) is a silicon alkoxide in which X in formula (I) is an alkoxyl group. Moreover, it is more preferable that the silicon alkoxide includes a tetrafunctional silicon alkoxide corresponding to the compound (SiX ₄ ) where m=0 in formula (I). Specific examples of the tetrafunctional silicon alkoxide include tetramethoxysilane and tetraethoxysilane. The silicon alkoxide may be used alone or in combination of two or more types. When two or more types are used in combination, it is more preferable that the main component of the silicon alkoxide is a tetrafunctional silicon alkoxide.

More preferably, the silicon alkoxide includes a tetrafunctional silicon alkoxide and a trifunctional silicon alkoxide corresponding to the compound (RSiX ₃ ) where m=1 in formula (I). Specific examples of trifunctional silicon alkoxides having no reactive functional group include methyltriethoxysilane, ethyltriethoxysilane, n-propyltriethoxysilane, and the like. Specific examples of trifunctional silicon alkoxides having reactive functional groups include glycidoxyalkyltrialkoxysilanes (3-glycidoxypropyltrimethoxysilane, etc.), aminoalkyltrialkoxysilanes (3-aminopropyltriethoxysilane, etc.) ) etc.

Silicon alkoxides with reactive functional groups are sometimes called silane coupling agents. A bifunctional silicon alkoxide corresponding to the compound (R ₂ SiX ₂ ) where m=2 in formula (I) is also a silane coupling agent when at least one of R is a reactive functional group. Specific examples of bifunctional silicon alkoxides in which at least one of R has a reactive functional group include glycidoxyalkylalkyldialkoxysilane (3-glycidoxypropylmethyldimethoxysilane, etc.), aminoalkylalkyldialkoxysilane [N -2-(aminoethyl)-3-aminopropylmethyldimethoxysilane, etc.].

When the ultraviolet absorber or infrared absorber is an organic substance, it is particularly preferable that the silicon alkoxide contains a silane coupling agent. This is because the light shielding property (for example, ultraviolet shielding property) by the ultraviolet absorber or the infrared absorber is improved. The reason why the light shielding property of the organic-inorganic composite antifogging film is improved by the silane coupling agent is that by adding the silane coupling agent, the light absorbing agent, which is an organic compound, is more uniformly dispersed in the water-absorbing resin containing silica. This is thought to be due to the fact that

A silicon compound having a hydrolyzable group represented by the formula (I) supplies a component represented by the following formula (II) when hydrolysis and polycondensation proceed completely.

R _m SiO _(4-m)/2 (II)
R and m in formula (II) are as described above. After hydrolysis and polycondensation, the compound represented by formula (II) actually has silicon atoms and oxygen atoms connected alternately and spread three-dimensionally in the organic-inorganic composite antifogging film. Forms a network structure of siloxane bonds (Si-O-Si).

When the content of silica derived from tetrafunctional silicon alkoxide or trifunctional silicon alkoxide in the organic-inorganic composite antifogging film increases, the antifogging properties of the organic-inorganic composite antifogging film may decrease. One reason for this is that the flexibility of the organic-inorganic composite antifogging film is reduced, and swelling and contraction of the film due to absorption and release of water are restricted. Silica derived from tetrafunctional silicon alkoxide is preferably added in an amount of 0 to 30 parts by weight, more preferably 1 to 20 parts by weight, and still more preferably 3 to 10 parts by weight, per 100 parts by weight of the water absorbent resin. . Silica derived from trifunctional silicon alkoxide is preferably in the range of 0 to 30 parts by weight, more preferably 0.05 to 15 parts by weight, and still more preferably 0.1 to 10 parts by weight, based on 100 parts by weight of the water absorbent resin. It is best to add it with

Examples of the ultraviolet absorber include benzotriazole compounds [2-(2'-hydroxy-5'-methylphenyl)benzotriazole, 2-(2'-hydroxy-3',5'-di-t-butylphenyl) benzotriazole, etc.], benzophenone compounds [2,2',4,4'-tetrahydroxybenzophenone, 2,4-dihydroxybenzophenone, 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-octoxybenzophenone, 5, 5'-methylenebis(2-hydroxy-4-methoxybenzophenone), etc.], hydroxyphenyltriazine compounds [2-(2-hydroxy-4-octoxyphenyl)-4,6-bis(2,4-di-t- butylphenyl)-s-triazine, 2-(2-hydroxy-4-methoxyphenyl)-4,6-diphenyl-s-triazine, 2-(2-hydroxy-4-propoxy-5-methylphenyl)-4, 6-bis(2,4-di-t-butylphenyl)-s-triazine, etc.] and cyanoacrylate compounds [ethyl-α-cyano-β,β-diphenylacrylate, methyl-2-cyano-3-methyl-3 -(p-methoxyphenyl)acrylate, etc.]. The ultraviolet absorbers may be used alone or in combination of two or more. Further, the ultraviolet absorber may be at least one organic dye selected from polymethine compounds, imidazoline compounds, coumarin compounds, naphthalimide compounds, perylene compounds, azo compounds, isoindolinone compounds, quinophthalone compounds, and quinoline compounds. . Preferred among the UV absorbers are organic UV absorbers, more preferred is at least one selected from benzotriazole compounds, benzophenone compounds, hydroxyphenyltriazine compounds, and cyanoacrylate compounds, and even more preferred is a benzophenone compound. The benzophenone compound is preferable because it has good solubility in the alcohol solvent contained in the coating liquid for forming the organic-inorganic composite antifogging film and is more uniformly dispersed in the polyvinyl acetal resin. The ultraviolet absorber preferably has a hydroxyl group, and more preferably has two or more hydroxyl groups bonded to one benzene skeleton of the ultraviolet absorber. The ultraviolet absorber is preferably added in an amount of 0.1 to 50 parts by weight, more preferably 1.0 to 40 parts by weight, even more preferably 2 to 35 parts by weight, per 100 parts by weight of the water absorbent resin.

Examples of infrared absorbers include polymethine compounds, cyanine compounds, phthalocyanine compounds, naphthalocyanine compounds, naphthoquinone compounds, anthraquinone compounds, dithiol compounds, immonium compounds, diimonium compounds, aminium compounds, pyrylium compounds, cerylium compounds, squarylium compounds, and benzene. Organic infrared absorbers such as counterion combinations of dithiol metal complex anions and cyanine dye cations; tungsten oxide, tin oxide, indium oxide, magnesium oxide, titanium oxide, chromium oxide, zirconium oxide, nickel oxide, aluminum oxide, oxide Examples include inorganic infrared absorbers such as zinc, iron oxide, ammonium oxide, lead oxide, bismuth oxide, lanthanum oxide, tungsten oxide, indium tin oxide, and antimony tin oxide. Infrared absorbers may be used alone or in combination of two or more. Among the infrared absorbers, inorganic infrared absorbers are preferred, and indium tin oxide and/or antimony tin oxide are more preferred. Indium tin oxide and/or antimony tin oxide are preferable because they have good stability in a coating liquid for forming an organic-inorganic composite antifogging film and are more uniformly dispersed in polyvinyl acetal resin. The infrared absorber is preferably added in an amount of 0.1 to 50 parts by weight, more preferably 1.0 to 40 parts by weight, and even more preferably 2 to 35 parts by weight, per 100 parts by weight of the water absorbent resin.

(Crosslinked structure)
The organic-inorganic composite antifogging film may include a crosslinked structure derived from at least one crosslinking agent selected from an organic boron compound, an organic titanium compound, and an organic zirconium compound. Introduction of the crosslinked structure improves the abrasion resistance and water resistance of the organic-inorganic composite antifogging film. Stated from another perspective, the introduction of the crosslinked structure facilitates improving the durability of the organic-inorganic composite antifogging film without reducing its antifogging performance.

The type of crosslinking agent is not particularly limited as long as it can crosslink the water absorbent resin used. Here, only examples of organic titanium compounds will be given. The organic titanium compound is, for example, at least one selected from titanium alkoxide, titanium chelate compound, and titanium acylate. Titanium alkoxides are, for example, tetratetraisopropoxide, titanium tetra-n-butoxide, titanium tetraoctoxide. Titanium chelate compounds are, for example, titanium acetylacetonate, titanium ethyl acetoacetate, titanium octylene glycol, titanium triethanolamine, and titanium lactate. Titanium lactate may be an ammonium salt (ammonium titanium lactate). Titanium acylate is, for example, titanium stearate. Preferred organotitanium compounds are titanium chelate compounds, especially titanium lactate.

When the water-absorbing resin is a polyvinyl acetal resin, a preferred crosslinking agent is an organic titanium compound, especially titanium lactate.

(Other optional ingredients)
Other additives may be added to the organic-inorganic composite antifogging film. Examples of additives include glycols such as glycerin and ethylene glycol, which have the function of improving antifogging properties. The additive may be a surfactant, a surfactant, a slip agent, a leveling agent, an antifoaming agent, a preservative, or the like.

(hydrophilic type)
The above-mentioned antifogging film is a water-absorbing type containing a water-absorbing resin as a main component, but a hydrophilic type can also be adopted. The hydrophilic type has a hydrophilic resin as its main component, and known ones such as the antifogging film described in JP-A No. 2011-213555 can be used. Specifically, it is as follows.

Preferably, a plurality of closed pores are formed inside the anti-fog film. In addition, the antifogging film has a double-chain anionic interface mainly composed of silicon oxide and having two carbon chains each having 6 or more carbon atoms at branched positions when viewed from the hydrophilic group. It is preferable that the silicon oxide contains an activator and a polyol compound, and it is preferable that the silicon oxide contains silicon oxide fine particles and a silicon oxide component produced by a hydrolysis reaction and a polycondensation reaction of silicon alkoxide. Note that "closed pores" are pores that are not open to the membrane surface. The term "main component" as is commonly used means the component that is present in the largest amount, and specifically refers to a component that accounts for 50% by mass or more. A "polyol compound" is a polyhydric alcohol such as a diol or triol.

In addition, such a hydrophilic type anti-fog film is produced by applying an anti-fog film forming solution containing silicon alkoxide and silicon oxide fine particles to form a coating film, and drying this coating film to form an anti-fog film. You can get it by doing so. The antifogging film forming solution contains at least 1) a double-stranded anionic surfactant, 2) a polyol compound, 3) silicon oxide fine particles (silica fine particles), and 4) at least a portion of which is silicon tetraalkoxide. It can be prepared by mixing silicon alkoxide, 5) water, 6) organic solvent, and 7) hydrolysis catalyst. However, the hydrophilic type antifogging film is not limited to this.

[Film thickness]
The thickness of the organic-inorganic composite antifogging film may be adjusted as appropriate depending on the required antifogging properties and other factors. The thickness of the organic-inorganic composite antifogging film is preferably 1 to 20 μm, more preferably 2 to 15 μm, and still more preferably 3 to 10 μm.

Note that the above-mentioned antifogging film is just an example, and the ultraviolet absorber or infrared absorber is not essential. Further, other known anti-fog films can be used, such as various anti-fog films described in JP-A-2014-14802 and JP-A-2001-146585.

<4. Windshield manufacturing method＞
Next, an example of a method for manufacturing a windshield will be described. First, the glass plate manufacturing line will be explained.

As shown in FIG. 11, in this manufacturing line, a heating furnace 901 and a molding device 902 are arranged in this order from upstream to downstream. A roller conveyor 903 is arranged from the heating furnace 901 to the forming device 902 and downstream thereof, and the glass plate 10 to be processed is conveyed by the roller conveyor 903. The glass plate 10 is formed into a flat plate shape before being carried into the heating furnace 901, and after the mask layer 2 described above is laminated on the glass plate 10, it is carried into the heating furnace 901.

Although various configurations are possible for the heating furnace 901, for example, it can be an electric heating furnace. The heating furnace 901 includes a rectangular cylindrical furnace body with open upstream and downstream ends, and a roller conveyor 903 is arranged inside the furnace body from upstream to downstream. Heaters (not shown) are arranged on the upper surface, lower surface, and a pair of side surfaces of the inner wall surface of the furnace body, respectively, to maintain the temperature at which the glass plate 10 passing through the heating furnace 901 can be formed, for example, the softening point of the glass. Heat to around 100 ml.

The molding device 902 is configured to press a glass plate using an upper mold 921 and a lower mold 922 and mold it into a predetermined shape. The upper mold 921 has a downwardly convex curved shape that covers the entire upper surface of the glass plate 10, and is configured to be movable up and down. Further, the lower mold 922 is formed into a frame shape corresponding to the peripheral edge of the glass plate 10, and its upper surface has a curved shape so as to correspond to the upper mold 921. With this configuration, the glass plate 10 is press-molded between the upper mold 921 and the lower mold 922, and is molded into the final curved shape. Further, a roller conveyor 903 is arranged within the frame of the lower die 922, and this roller conveyor 903 can move up and down so as to pass through the frame of the lower die 922. Although not shown, a slow cooling device (not shown) is disposed downstream of the forming device 902 to cool the formed glass plate.

The roller conveyor 903 as described above is a known one, and has a plurality of rollers 931 rotatably supported at both ends thereof, which are arranged at predetermined intervals. Although there are various methods for driving each roller 931, for example, a sprocket can be attached to the end of each roller 931, and a chain can be wound around each sprocket. By adjusting the rotation speed of each roller 931, the conveyance speed of the glass plate 10 can also be adjusted. The lower mold 922 of the molding device 902 may be in contact with the entire surface of the glass plate 10. In addition, the shapes of the upper mold and the lower mold are not particularly limited in the molding device 902 as long as it molds a glass plate.

After the outer glass plate 11 and inner glass plate 12 are formed in this way, the interlayer film 13 is then sandwiched between the outer glass plate 11 and the inner glass plate 12, placed in a rubber bag, and vacuum suctioned. Preliminary bonding is performed at approximately 70 to 110°C. Other methods of preliminary adhesion are also possible. For example, the interlayer film 13 is sandwiched between the outer glass plate 11 and the inner glass plate 12, and heated at 45 to 65° C. in an oven. Subsequently, this laminated glass is pressed with a roll at 0.45 to 0.55 MPa. Next, this laminated glass is heated again at 80 to 105° C. in an oven, and then pressed again with a roll at 0.45 to 0.55 MPa. In this way, preliminary adhesion is completed.

Next, main adhesion is performed. The pre-bonded laminated glass is subjected to main bonding in an autoclave at, for example, 8 to 15 atm and 100 to 150°C. Specifically, the main bonding can be performed under conditions of, for example, 14 atm and 145°C. In this way, the laminated glass according to this embodiment is manufactured.

In addition, when using one glass as a glass plate, it is sufficient to use one of the above-mentioned glasses. The manufacturing method of the glass plate is also similar, and after forming a mask layer on the inner surface of the glass plate, heating is performed, and then the glass plate is formed into a curved shape.

Subsequently, an antifogging film is formed. The above-mentioned organic-inorganic composite anti-fog film can be formed by applying a coating liquid for forming the organic-inorganic composite anti-fogging film onto an article such as a transparent substrate, and drying the applied coating liquid. I can do it. For the solvent used to prepare the coating liquid and the method for applying the coating liquid, known materials and methods may be used.

First, the openings in the mask layer 2 are cleaned, and then a coating liquid for an antifogging film is applied to the openings in the mask layer 2 by screen printing or the like. At this time, it is preferable to maintain the relative humidity of the atmosphere at less than 40%, more preferably at most 30%. Keeping the relative humidity low can prevent the organic-inorganic composite antifogging film from absorbing excessive moisture from the atmosphere. If a large amount of water is absorbed from the atmosphere, the remaining water that enters the matrix of the organic-inorganic composite antifogging film may reduce the strength of the film.

It is preferable that the drying process of the coating liquid includes an air drying process and a heating drying process that involves heating. The air-drying step is preferably carried out by exposing the coating liquid to an atmosphere in which the relative humidity is maintained at less than 40%, preferably at most 30%. The air drying process can be performed as a non-heating process, in other words, at room temperature. When the coating liquid contains a hydrolyzable silicone compound, in the heat drying process, a dehydration reaction involving silanol groups contained in the hydrolyzate of the silicone compound and hydroxyl groups present on the article progresses, and the silicone A matrix structure (network of Si--O bonds) consisting of atoms and oxygen atoms develops. The air drying process can be performed for about 10 minutes, for example.

In order to avoid decomposition of organic substances such as water-absorbing resins, the temperature applied in the heating and drying step should not be excessively high. A suitable heating temperature in this case is 300°C or less, for example 100 to 200°C. Specifically, three steps can be performed. For example, it is baked at a temperature of about 120°C for about 5 minutes, dried at a temperature of about 80°C and humidity of 90% for about 2 hours, and then baked at a temperature of about 120°C for about 30 minutes. In this way, the formation of the antifogging film is completed.

<5. Measurement unit>
Next, the measurement unit (information acquisition device) will be explained with reference to FIGS. 12 and 13. FIG. 12 is a sectional view showing a schematic configuration of the measurement unit 4 attached to the glass plate, and FIG. 13 is a diagram (a) of the bracket seen from the outside of the vehicle and a diagram (b) of the bracket seen from the inside of the vehicle. As shown in FIG. 12, this measurement unit 4 includes a bracket 41 fixed to the inner surface of the glass plate 1, a sensor 5 supported by the bracket 41, and a cover 42 that covers the bracket 41 and sensor 5 from inside the vehicle. It is made up of.

As shown in FIG. 13, the bracket 41 is formed in a rectangular shape and is fixed to the center mask layer 22 formed on the vehicle-inward side surface of the inner glass plate 12 as described above with an adhesive 401. In addition, two openings, a first opening 411 and a second opening 412, arranged vertically and separated by a partition part 415 are formed in this bracket 41, and a large first opening 411 formed on the upper side is formed. A sensor 5 is attached to. Further, in this bracket, a trapezoidal recess 414 is formed below the second opening 412 when viewed from the outside of the vehicle. The recess 414 is inclined such that the upper end is deepest and becomes shallower toward the lower end, and a second opening 412 is formed at the upper end. Further, as shown in FIG. 13(b), support parts 413 for supporting the sensor 5 are attached to both sides of the first opening 411 on the vehicle-inward surface of the bracket 41. It is fixed between 413 and 413. As will be described later, an irradiation lens 552 is attached to the tip of the fixed sensor 5 (lower end in FIG. 12), and the irradiation lens 552 faces the outside through the second opening 412 and the recess 414. It has become. That is, the recess 414 forms a gap with the glass plate, and serves as a path for light irradiated from the second opening 412. On the other hand, the light receiving lens 542 faces the outside through the first aperture 411.

Further, as shown in FIG. 13(a), the outer surface of the bracket 41 is a surface to be fixed to the center mask layer 22, and a bead-shaped adhesive 401 is applied thereto. The adhesive 401 is applied approximately all around the bracket 41, and the bracket 41 is fixed to the center mask layer 22 via the adhesive 401. Note that various adhesives can be used, and for example, urethane resin adhesives, epoxy resin adhesives, etc. can be used. However, epoxy resin adhesives are advantageous because they are difficult to flow due to their high viscosity. Furthermore, if the mask layer 2 is not formed on the vehicle-inward side surface of the inner glass plate 12, the bracket 41 is directly bonded to the inner glass plate 12. Note that the method for fixing the bracket 41 is not particularly limited, and in addition to adhesives, double-sided tape may be used, or both adhesives and double-sided tape may be used.

After a harness (not shown) is attached to the bracket 41, a cover 42 is attached from the inside of the vehicle, as shown in FIG. This makes the sensor 5 and the bracket 41 invisible from inside the vehicle. In this way, the sensor 5 is housed in a space surrounded by the bracket 41, the cover 42, and the glass plate 1. Note that since the center mask layer 22 is formed, the measurement unit 4 is not visible from the outside of the vehicle except for the upper opening 231 and the lower opening 232. Furthermore, the upper opening 231 and the lower opening 232 are surrounded by the bracket 41 and are not visible from inside the vehicle.

Next, an outline of the sensor 5 will be explained with reference to FIG. 12. As shown in the figure, the sensor 5 includes a casing 51 that is triangular in side view, and the inside of the casing 51 is partitioned into an upper space 501 and a lower space 502. Furthermore, a connector 53 is attached to the back side of the housing 51 and is used for connection to external equipment.

A first support part 54 is arranged in the upper space 501, and a first control board 541 and a light receiving lens 542 are arranged in this first support part 54 from the rear to the front. Further, a light receiving element 543 is mounted on the first control board 541, and is adapted to receive the laser light that has passed through the light receiving lens 542 and convert it into an electrical signal. This electrical signal is amplified in the first control board 541 and transmitted to the second control board 56, which will be described later. As described above, the light receiving lens 542 is arranged so as to face the outside from the first opening 411 of the bracket 41 through the upper opening 231 of the center mask layer 22. In particular, the sensor 5 is supported by the bracket 41 so that the path of light received by the light receiving element 543 passes near the center X of the upper opening 231 (see FIG. 12). Further, reflected light from many directions reflected from a preceding vehicle or an obstacle passes near the center of the upper opening 231, and the light receiving element 543 receives the reflected light.

On the other hand, a second support part 55 is arranged in the lower space 502, and a laser emitting element 551 and an irradiation lens 552 are supported in this order from the back to the front. The laser emitting element 551 is a device such as a laser diode that emits laser light in the near-infrared wavelength range of 850 nm to 950 nm, and the irradiation lens 552 is a lens that shapes the laser light from the laser emitting element 551 into a predetermined beam shape. It is. As described above, the irradiation lens 552 is arranged so as to face the outside from the housing 51 through the second opening 412 of the bracket 41 and the lower opening 232 of the center mask layer 22. In particular, the position and size of the lower opening 232 and the mounting position of the sensor 5 are adjusted so that the passage path of the laser light emitted from the laser emitting element 551 passes through the center Y of the lower opening 232 (see FIG. 12). ing.

Further, a second control board 56 is arranged on the upper surface of the second support part 55, and performs driving of the laser emitting element 551, processing of electrical signals transmitted from the first control board 541, and the like.

Next, the operation of the measurement unit 4 will be explained. First, the first control board 541 emits a pulse of laser light from the laser light emitting element 551. Then, based on the time it takes for the light receiving element 543 to receive the reflected light from the laser beam reflected by the preceding vehicle or obstacle, the distance between the preceding vehicle or obstacle and the own vehicle is calculated. The calculated distance is transmitted to an external device via the connector 53 and used for brake control and the like.

<6. Features>
<6-1>
According to the windshield described above, the following effects can be obtained. First, by laminating an antifogging film over the openings 231 and 232 of the mask layer 2, the openings 231 and 232 can be prevented from fogging up. Therefore, when the measurement unit irradiates or receives light through the apertures 231, 232, the apertures 231, 232 are clouded, which obstructs the passage of light and prevents problems such as inability to perform accurate measurements. can do. For example, FIG. 14 is a photograph of a windshield coated with the organic-inorganic composite anti-fog film shown in the above embodiment, but there is no fogging in the area on the right side of the windshield where the anti-fog film is coated. First, it can be seen that the antifogging film has a very large effect in preventing fogging.

In particular, the upper part of the car interior where the openings 231 and 232 of the mask layer 2 are provided tends to get cold and foggy even when the heating is turned on. Therefore, it is advantageous that the anti-fog film is laminated at such a position. Further, the openings 231 and 232 of the mask layer 2 on which the antifogging film is laminated are arranged with measurement units facing each other, or are surrounded by a bracket 41. Therefore, there is a problem that warm air from the heater or defroster is difficult to reach. Therefore, as mentioned above, it is of great significance to provide an antifogging film in areas where warm air cannot reach easily.

Furthermore, there are also the following effects. There is a risk that the plasticizer that has separated from the interior parts of the vehicle (for example, resin molded products) and entered the air may adhere to the anti-fog film. If the plasticizer adheres to the antifogging film, the antifogging function may deteriorate. However, as described above, since the measurement unit is arranged at a position facing the anti-fog film and further surrounded by the bracket 41, it is possible to prevent the plasticizer from adhering to the anti-fog film. As a result, it is possible to prevent the antifogging function from deteriorating, especially in the case of a water absorbing type antifogging film. Furthermore, in the case of the hydrophilic type, since the plasticizer is likely to bond with the hydrophilic groups in the antifogging film, it is preferable that the measurement units be arranged facing each other or surrounded by the brackets 41 as described above.

Note that if the plasticizer adheres to the surface of a water-absorbing type anti-fog film and accumulates for a long period of time, it will inhibit water absorption and reduce the anti-fog performance. However, if you wipe off the plasticizer with a damp cloth, the water absorption performance will be restored. On the other hand, if a plasticizer adheres to the surface of a hydrophilic type antifogging film, it will strongly bond to the hydrophilic groups, resulting in a decrease in hydrophilic performance. Therefore, due to the difference in the thickness of the water film formed, there is a possibility that the image passing through the antifogging film may be distorted or the antifogging performance may be deteriorated in a short period of time.

Another possible method is to warm the vicinity of the openings 231 and 232 in the mask layer 2 with a heating wire to eliminate fogging, but there is a problem in that it takes time for the fogging to disappear after current is passed through the heating wire. Electricity consumption is also an issue. Furthermore, the method for eliminating fogging using a heating wire depends on the thickness of the glass plate and the outside air condition, and is not uniform. Therefore, an anti-fog film that prevents fogging in advance and also consumes no power would be very advantageous.

Furthermore, there is a problem that antifogging films generally have poor durability and are easily damaged by external forces. However, as described above, by arranging the measurement unit to face the antifogging film or by surrounding it with the bracket 41, scratches can be prevented.

<6-2>
Further, by providing an anti-fog film, an anti-reflection effect can be obtained. For example, by containing the above-mentioned inorganic oxide fine particles such as colloidal silica, it is possible to form irregularities smaller in size than the wavelength of light on the surface of the antifogging film, thereby creating a so-called "moth eye" structure. The anti-reflection effect caused by the anti-fogging film and the double image caused by the reflected light on the surface of the anti-fog film can be prevented. To obtain such an antireflection effect, for example, an antifogging film containing about 1% by weight of colloidal silica having a particle size of about 5 to 15 nm can be used. However, the particle size and content are not limited to this, as long as they can form irregularities on the surface of the antifogging film.

Further, as shown below, by providing an antifogging film having a refractive index lower than that of glass, the following antireflection effect can be obtained. FIG. 15A is a schematic diagram showing a state in which incident light from a glass plate (refractive index n _A ) is refracted at an air interface, and reflected light is generated at the interface. FIG. 15(b) is a schematic diagram of a state in which an antifogging film having a refractive index n _B is laminated on a glass plate. In FIG. 15(b), since the thickness of the antifogging film is much larger than the wavelength of light, it is assumed that interference of reflected light does not occur.

From the law of refraction, the relationship between the refractive index, the angle of incidence, and the angle of refraction is as follows: n _A sinθ _A = n _B sinθ _B = sinθ
For example, at the interface between refractive indices n _A and n _B , the reflectance is expressed by the Fresnel reflection formula Rp = tan ² (θ _A - θ _B )/tan ² (θ _A + θ _B )
Rs=sin ² (θ _A - θ _B )/sin ² (θ _A + θ _B )
It is expressed as Rp and Rs are reflectances of P-polarized light and S-polarized light, respectively.

By stacking the antifogging film, the number of reflective interfaces increases to two, but the difference in refractive index between the interfaces becomes smaller, so the total reflectance decreases. Here, the refractive index of the glass plate n _A = 1.52, the refraction angle _θ in air = 60°, and the combined reflectance of the two interfaces (P FIG. 16 shows the results of calculating the average of polarized light and S-polarized light based on the above formula.

From FIG. 16, if the refractive index n _B of the anti-fog film is higher than the refractive index of air and lower than the refractive index of glass, then in the absence of the anti-fog film (n _B =1.00 and n _B =1.00). 52), the combined reflectance of the two interfaces is lower. Therefore, using an anti-fog film with a refractive index higher than that of air and lower than that of glass has an anti-reflection effect, thereby preventing double images from occurring. You can also.

<7. Modified example>
Although one embodiment of the present invention has been described above, the present invention is not limited to the above embodiment, and various changes can be made without departing from the spirit thereof. Note that the following modifications can be combined as appropriate.

<7-1>
In the above embodiment, the anti-fog film is formed on the openings 231 and 232 of the mask layer 2, but it is sufficient that the anti-fog film is formed on at least the openings, and the mask layer including the openings, the upper part of the glass plate, or An anti-fog film may be formed on the entire glass plate.

<7-2>
Further, in the above embodiment, the anti-fog film is formed on the glass plate by applying a liquid agent, but an anti-fog film in which an anti-fog functional layer is formed on the base layer is used as an anti-fog film. The base layer side can also be attached to a glass plate. As such an anti-fog film, a known one can be used, and various types can be used, such as the anti-fog film disclosed in JP-A No. 2014-224213.

The antifogging functional layer can have the same composition as the antifogging film described above, and for example, can have a water-absorbing resin as a main component. Alternatively, a hydrophilic type containing a hydrophilic resin as a main component can also be used.

By using such an antifogging film, the following effects can be obtained. In other words, in addition to the problem that anti-fog films have low durability and are prone to scratches as mentioned above, there is a risk that plasticizers that have separated from the interior parts of the car and entered the air may adhere to the anti-fog films. There is also the problem of reduced functionality. On the other hand, when an anti-fog film is used, it is easy to reapply, so even if it gets scratched or the anti-fog function deteriorates, it can be easily replaced.

Further, similarly to the antifogging film, the antifogging functional layer can also contain inorganic oxide particles to form irregularities on the surface to improve the antireflection effect. Similarly, the antireflection effect can also be obtained by setting the refractive index of the antifogging functional layer to be higher than the refractive index of air and lower than the refractive index of the glass plate. Details regarding such an antireflection effect are as described above regarding the antifogging film.

<7-3>
Although the mask layer 2 has a three-layer structure as described above, it is not limited thereto. That is, in the above embodiment, the silver layer 242 is provided to shield electromagnetic waves, but a single layer of silver and a ceramic layer may be provided, or other materials may be used as long as they can shield electromagnetic waves, such as , copper, nickel, etc. may be laminated. Further, although the silver layer 242 is sandwiched between ceramic layers so as not to be visible from the outside, a member such as the above-mentioned cover may be used instead of covering with the ceramic layer. Further, the silver layer 242, which is an electromagnetic wave shielding layer, does not necessarily need to be provided, and any layer that is at least invisible from the outside may be sufficient.

The mask layer 2 can be made of a color other than black, and is not particularly limited as long as it is a dark color such as brown, gray, or dark blue that blocks the view from outside the vehicle and prevents the inside of the vehicle from being seen. Further, part or all of the mask layer may be formed of a shielding film that can be attached to a glass plate, thereby shielding the view from outside the vehicle. In addition, when attaching a shielding film to the vehicle exterior surface of the inner glass plate 12, it can be attached before preliminary adhesion or after main adhesion.

Further, from the viewpoint of preventing fogging of the light path in the glass plate, a mask layer is not necessarily necessary, and it is sufficient that an anti-fog film is formed in the region through which light passes (information acquisition region).

<7-4>
In the above embodiment, the sensor 5 that measures the inter-vehicle distance is used as the information acquisition device of the present invention, but the present invention is not limited to this, and various information acquisition devices can be used. That is, it is not particularly limited as long as it emits and/or receives light in order to acquire information from outside the vehicle. For example, a visible light and/or infrared camera to measure the distance between vehicles, a light receiving device such as an optical beacon that receives signals from outside the vehicle, and a camera that uses visible light and/or infrared light to read images of road white lines, etc. It can be applied to various devices such as. Here, when only one of light irradiation and light reception is performed, the center mask layer has one opening. Furthermore, a plurality of apertures can be provided depending on the type of light. Note that the information acquisition device may or may not be in contact with the glass. In any case, an anti-fog film is formed on the glass plate in a region through which light from the information acquisition device passes (information acquisition region).

<7-5>
In the above embodiment, an anti-fog film is provided inside the glass plate to prevent fogging of the information acquisition area, but instead of this, a heating wire may be provided as the anti-fog means according to the present invention. When heating wires are used, there is a high degree of freedom in wiring, so it is possible to flexibly respond to areas that need to be defogged. This will be explained in detail below.

In the example described below, heating wires are placed on the inner surface of the glass plate, and the information acquisition area is defogged by the heat generated by applying current. Although there are various wiring methods for the heating wire, it is preferable to arrange the heating wire so as not to interfere with the mask layer. As an example, the glass plate may be formed of laminated glass, a mask layer may be formed on the inner surface of the outer glass plate, and heating wires may be arranged on the inner surface of the inner glass plate. FIG. 17 shows an example of wiring formed on the inner surface of the glass plate, and also shows an opening through which light emitted from the information acquisition device passes, but this is on the inner surface of the outer glass plate. It is formed in the mask layer. Therefore, the heating wires placed on the inner surface of the inner glass plate do not interfere with the mask layer. The configuration of the heating wire will be explained below.

As shown in the figure, the heating wire 8 is disposed near the upper edge of the glass plate 1 and includes a pair of rectangular terminal portions 81 and 82 to which the positive and negative electrodes of the power source are connected. Hereinafter, the terminal portion connected to the positive electrode will be referred to as the first terminal portion 81, and the terminal portion connected to the negative electrode will be referred to as the second terminal portion 82. A first wiring portion 83 is formed extending downward from the first terminal portion 81 and further extending along one side edge (left side in the figure) of the opening 500 in the mask layer. This first wiring portion 83 extends to near the lower end of the opening 500. On the other hand, a second wiring part 84 is formed which extends downward from the second terminal part 82 and further extends to near the upper end of the other (right side in the figure) side edge of the opening 500. The width of the first and second wiring portions 83, 84 is, for example, preferably 3 to 25 mm, more preferably 5 to 10 mm.

A hot wire portion 85 is arranged between the lower end of the first wiring portion 83 and the lower end of the second wiring portion 84 . The hot wire portions 85 are arranged in an S-shape and are arranged to cross the opening 500 at three locations. The line width of the hot wire portion 85 is preferably, for example, 0.05 to 0.5 mm, and more preferably 0.1 to 0.3 mm.

In this way, the heating wire 8 includes a first terminal section 81, a first wiring section 83, a heating wire section 85, a second wiring section 84, and a second terminal section connected in series to a power source (voltage is constant). 82. Since heat is generated by applying the current, fogging can be prevented from occurring in the opening 500, and fogging that has occurred can be eliminated. In particular, in the heating wire 8 as described above, since the width of the heating wire portion 85 disposed in the opening 500 is narrow, the following effects can be obtained.

First, the heating wire 8 is short because it is arranged near the upper end of the glass plate 1. Therefore, for example, if the line width is large, the resistance may become small and the current flowing through the heating wire may become large (generally, the voltage is constant at 12 V or the like). As a result, the amount of heat generated becomes too large and there is a possibility of wire breakage, or an extra resistor must be placed to prevent wire breakage. On the other hand, if the line width of the hot wire portion 85 is made narrower as described above, the occurrence of such a problem can be prevented. Therefore, an appropriate amount of heat generation can be achieved, and an appropriate anti-fogging effect can be obtained. Furthermore, if the width of the hot wire portion 85 is made thinner, the visibility of the opening 500 is less likely to be obstructed, so that the opening 500 can be densely wired. In the example of FIG. 17, the hot wire portions 85 are arranged so as to cross the opening 500 at three locations, but the number of hot wire portions 85 may be more than this. This increases the resistance and prevents abnormal heat generation. Furthermore, dense wiring allows a higher anti-fog effect to be obtained over a wide range of the opening 500. Note that although the width of the hot wire portion 85 is narrow, when it is surrounded by a bracket as shown in the above embodiment, there is no contact from the outside, so that disconnection can be prevented.

In addition, the structure of the heating wire 8 mentioned above is an example, and it can be made into various wiring shapes. For example, the thin hot wire portions 85 may be placed directly from the terminal portions 81 and 82 without providing the wiring portions 83 and 84 described above. Further, since the heating wire 8 is formed of a single material in series with the power source, there is an advantage that the amount of heat generated does not become too large compared to a case where the heating wire 8 has parallel parts.

The heating wire 8 as described above can be made of various conductive materials, such as silver, copper, tungsten, etc. In addition to using these materials alone, it is also possible to adopt a laminated structure in which the heating wire 8 is coated with at least one layer of coating material. For example, when the heating wire is made of silver, a dark ceramic layer similar to the mask layer can be placed on the glass plate as a covering material, and the heating wire 8 made of silver can be formed on it. . In this way, the silver heating wire 8 will not be visible from outside the vehicle, resulting in a better appearance. In particular, if the ceramic layer and the mask layer have the same color, there will be no discomfort when viewed from outside the vehicle. Furthermore, the heating wire 8 can also be sandwiched between coating materials. That is, a three-layer structure may be used in which a coating material is placed on the glass plate 1, a heating wire 8 is placed thereon, and a covering material is placed so as to cover the heating wire 8. As a result, the heating wire 8 is no longer visible from inside the vehicle. In particular, if the silver layer is exposed in the opening 500 through which light passes, it is not preferable because the light may be reflected or otherwise hinder the passage of light. Therefore, if a dark ceramic layer is formed as a covering material on the silver layer, the silver layer will not be visible from inside the vehicle. Furthermore, since the heating wire 8 is arranged on the vehicle-inward side of the glass plate, there is a possibility that a bracket may be attached to the heating wire 8 via an adhesive. In this case, the components of the adhesive may corrode the silver. Therefore, from this point of view as well, coating silver with a ceramic layer can prevent the silver from being affected by the adhesive.

The layered structure including such heating wire 8 can have various forms. For example, the terminal parts 81 and 82 described above are made up of two layers (a ceramic layer and a silver layer are laminated in this order from the glass plate side), and the wiring parts 83 and 84 are made of three layers (a ceramic layer, a silver layer, and a ceramic layer are laminated from the glass plate side). laminated in this order), the hot wire portion 85 can be formed of only the silver layer. Note that the line width of the covering material is preferably larger than that of the heating wire. Moreover, the coating material that covers the silver layer may be other than ceramic.

When arranging the heating wire 8, interference can be prevented by arranging the mask layers on different surfaces of the laminated glass as described above, but it is preferable to form the heating wire and the mask layer on the same surface. You can also do it. In this case, the shape of the mask layer may be determined so that the heating wire and the mask layer do not interfere with each other. For example, the mask layer may not be formed in the portion where the heating wire is arranged. Furthermore, in addition to forming the heating wire 8 and the coating material on the inner surface of the glass plate 1, when the glass plate is made of laminated glass, the heating wire 8 and the coating material are formed on the inner surface of the outer glass plate, the outer surface of the inner glass plate, or the inner surface of the inner glass plate. It can also be formed on the inner surface. This also contributes to preventing interference with the mask layer.

The heating wire 8 as described above can be arranged on the glass plate in various ways. For example, after a glass plate is molded, a heating wire can be formed by forming on the glass plate by screen printing or the like and baking it in the same manner as the mask layer. When the mask layer is formed on the same side of the glass plate, it can be printed together with the mask layer and fired at the same time. In addition, it can also be formed on a glass plate by transfer. An example is shown below.

First, as shown in FIG. 18, a transfer sheet is prepared. The transfer sheet includes a release film 101, heating wires 8 formed thereon by screen printing or the like, and an adhesive layer 102 disposed to cover the heating wires 8. The release film 101 is a known one, and the heating wire 8 is the one described above. The adhesive layer 102 may be made of resins such as acrylic, methylcellulose, nitrocellulose, ethyl, cellulose, vinyl acetate, polyvinyl butyral, polyvinyl acetal, polyvinyl alcohol, and polyester, and may be used alone or as a mixture of these resins. Note that the adhesive layer 102 can be covered with a removable protective film or the like until the transfer.

Then, as shown in FIG. 19(a), the adhesive layer 102 of this transfer sheet is attached to the molded glass plate 1, and then the release film 101 is peeled off. Thereby, as shown in FIG. 19(b), the adhesive layer 102 and the heating wire 8 are arranged in this order on the glass plate 1. Thereafter, when this glass plate 1 is fired, the adhesive layer 102 is melted and the heating wire 8 is baked onto the glass plate, as shown in FIG. 19(c). For example, when an acrylic adhesive is used as the adhesive layer 102, the heating wire can be transferred to the glass plate by baking at about 400 to 700° C. for about 3 minutes. Note that this transfer sheet is just an example, and any transfer sheet may be used as long as it can transfer the heating wire 8 onto the glass plate 1. For example, the transfer sheet described in JP-A No. 2009-23255 may be used. can be used.

As described above, forming the heating wire 8 using the transfer sheet has the following advantages. First, it is easier to form the heating wire 8 on the release film 101 than to form it directly on the glass plate 1, and the degree of freedom is higher. Moreover, if such a transfer film is produced in large quantities, the productivity when forming the heating wire 8 on the glass plate 1 will be improved.

The heating wire may have a shape other than that shown in FIG. 17, for example, as shown in FIG. 20. In the example of FIG. 20, the mask layer is omitted and only the opening 500 is shown. As shown in FIG. 17, this heating wire 8 has a first terminal part 81 arranged near the upper edge of the glass plate 1 and a second terminal part 82 connected to the negative electrode. There is. A first wiring portion 83 is formed that extends downward from the first terminal portion 81 to near the upper edge of the opening 500. Similarly, a second wiring portion 84 is formed that extends downward from the second terminal portion 82 to near the upper edge of the opening 500. A third wiring part 85 is formed from the lower ends of the first wiring part 83 and the second wiring part 84, extending along the outer periphery of the opening 231. This third wiring section 85 is configured by connecting five linearly extending parts, that is, first to fifth parts 85a to 85e, so as to surround a trapezoidal opening, and each part 85a 85e are formed in a wave shape.

By arranging the heating wire 8 around the opening 231 in this manner, heat can be transferred to the inside of the opening 231, and fogging inside the opening 231 can be prevented. The reason why the parts 85a to 85e of the heating wire 8 are formed in a waveform in this way is to increase the overall length of the heating wire 8 and increase its resistance. As a result, the current value does not become too large for a constant power supply voltage (generally, the voltage is 12V, etc.), and heat generation can be controlled while preventing the heating wire 8 from breaking.

Further, the heating wire shown in FIG. 17 and the heating wire shown in FIG. 20 can be combined into a shape. That is, while surrounding the opening with a heating wire as shown in FIG. 20, it is also possible to arrange a heating wire as shown in FIG. 17 inside the opening. Furthermore, in order to increase the resistance of the heating wire, for example, at least a portion of the first wiring portion 83 and the second wiring portion 84 in the heating wire shown in FIG. 17 may be formed into a wave shape. In this way, the shape of the heating wire is not particularly limited. Moreover, the heating wire 8 can be provided on any of the mask layer, the bracket, and the glass plate.

Furthermore, a heating wire and an anti-fog film can also be combined. For example, heating wires 85 as shown in FIG. 20 may be disposed on the glass plate, and the above-mentioned anti-fogging film may be disposed in a region including at least the opening 500.

At this time, the antifogging film may be provided directly on the glass plate 1, or may be provided as follows. For example, an antifogging film can be placed on a sheet-like base material, and then this base material can be attached to a glass plate using a transparent adhesive. Moreover, the adhesive, the base material, and the antifogging film can also be laminated in this order. The base material can be formed from a transparent resin sheet such as polyethylene or polyethylene terephthalate.

The anti-fog film and the heating wire can also be arranged as follows. First, as shown in FIG. 21(a), a base material 502 is formed to be larger than the opening 500, and placed on the glass plate 1 via the adhesive 503 so as to cover the opening 500 and its surroundings. Next, a heating wire 85 is formed on the peripheral edge of the base material 502 in a region protruding from the opening 500 by printing or the like. Finally, an antifogging film 501 is formed on almost the entire surface of the base material 502 so as to cover the heating wire 85. Alternatively, as shown in FIG. 21(b), after forming the heating wire 85 on the periphery of the base material 502, the anti-fog film 501 is formed on the base material 502 in a region inside the heating wire 85. That is, the size of the antifogging film 501 is made almost the same as the opening 500, and the heating wire 85 is arranged in a region of the base material 502 that protrudes from the opening 500. Note that the mask layer is omitted in FIG. 21 and FIG. 22 described later.

By adopting the mode as shown in FIG. 21, the following effects can be obtained. That is, as described above, when a water-absorbing type of antifogging film is used, it absorbs a predetermined amount of moisture and once it becomes saturated, it is no longer able to absorb any more moisture, and its antifogging function deteriorates. On the other hand, when the heating wire 85 is placed around the anti-fog film 501, the heat of the heating wire 85 can evaporate moisture from the anti-fog film 501, thereby preventing the anti-fog film 501 from becoming saturated. can be suppressed. As a result, deterioration of the anti-fogging function can be prevented.

Further, for example, when the heating wire 85 is formed by printing and fired, the temperature becomes high, so if the anti-fog film 501 is formed before the heating wire 85, there is a risk that the anti-fog film 501 will vaporize. As described above, if the anti-fog film 501 is formed after the heating wire 85 is formed, vaporization of the anti-fog film 501 can be prevented. Note that the base material 502 may be placed only on the glass plate 1 (the entire opening 500 or a part of the opening 500), or a part of the base material 502 may be placed on the mask layer as shown in FIG.

Alternatively, you can do the following. As shown in FIG. 22, after forming heating wires 85 on the periphery of the base material 502, a transparent conductive film (for example, ITO, etc.) 504 is placed on the region inside the heating wires 85 on the base material 502, and then An anti-fog film 501 can be placed thereon. At this time, the base material 502 is formed larger than the opening 500, and the transparent conductive film 504 and the antifogging film 501 are formed in substantially the same shape as the opening 500. Furthermore, wiring is provided to the transparent conductive film 504 so that electricity can be supplied thereto. With this configuration, the heating wire 85 and the transparent conductive film 504 generate heat, and water can be evaporated from the anti-fog film 501, so it is possible to prevent the anti-fog film 501 from becoming saturated. .

Note that in the embodiment of FIG. 22, the antifogging film 501 can also be heated only by the transparent conductive film 504 without disposing the heating wire 85. Furthermore, only the transparent conductive film 504 provided with wiring can be placed on the glass plate 1 or on the glass plate 1 via the base material 502 and the adhesive 503. That is, anti-fogging can be performed only by heat generation of the transparent conductive film 504.

As mentioned above, various types of anti-fog means can be employed, including only an anti-fog film, only a heating wire, only a transparent conductive film, or a combination of any of these means. You can also.

<7-6>
A stereo camera can be used as the information acquisition device. Although a known stereo camera can be used, a specific example will be described below with reference to FIGS. 23 and 24.

As shown in FIGS. 23 and 24, the stereo camera is placed inside a glass plate and has two imaging devices 210A and 210B spaced apart from each other so that two images with parallax can be acquired simultaneously. are doing. Correspondingly, the center mask layer 22 includes two photographing windows 113A corresponding to each photographing device 210A, 210B arranged in the vehicle so that each photographing device 210A, 210B arranged inside the vehicle can photograph the situation outside the vehicle. , 113B are formed. These two photographing windows 113A and 113B are arranged symmetrically near the support portion of the rearview mirror with the rearview mirror as an axis of symmetry. Further, on the inner surface of the glass plate, the above-mentioned anti-fogging film is provided at positions corresponding to the photographing windows 113A and 113B.

Further, the stereo camera 20 is connected to an image processing device 30, and constitutes an in-vehicle system that can analyze the distance between a subject and the own vehicle using a plurality of images acquired by the stereo camera 20. Each component will be explained below.

Each photographing device 210A, 210B of the stereo camera 20 can be a known device, for example, a lens system having a plurality of lenses and an aperture diaphragm, and an image sensor such as a CCD that takes an image using light that has passed through the lens system. , can be provided. An image of a subject is captured by using an image sensor to form an image of light that has passed through a lens system on a light-receiving plane. The stereo camera 20 can simultaneously acquire a plurality of images with parallax using each of the photographing devices 210A and 210B.

The image processing device 30 is a device that analyzes a plurality of images acquired by the stereo camera 20 and analyzes the distance between the subject and the own vehicle, the moving speed of the subject, the type of the subject, etc., and may be a known device. I can do it. Such an image processing apparatus has general hardware such as a storage section, a control section, and an input/output section that are connected via a bus.

Since the stereo camera 20 described above uses two photographing devices 210A and 210B, if one of the two photographing windows 113A and 113B becomes cloudy, correct image analysis may not be possible. Therefore, it is very advantageous to form an anti-fog film, an anti-fog film, or a heating wire as described above on the photographic windows 113A and 113B.

1 Glass plate 2 Mask layers 231, 232 Opening (information acquisition area)
113A, 113B Photography window (information acquisition area)

Claims (9)

A windshield in which an information acquisition device that acquires information from outside the vehicle by emitting and/or receiving light can be placed,
glass plate and
at least one anti-fog means provided on the glass plate;
Equipped with
The glass plate has at least one information acquisition area that faces the information acquisition device and through which the light passes,
One of the anti-fogging means includes a heating wire for anti-fogging the information acquisition area,
The heating wire is
a first wiring part connected to a positive electrode of a power source and extending to a periphery of the information acquisition area;
a second wiring part connected to the negative electrode of the power source and extending to the periphery of the information acquisition area;
a hot wire portion formed of a single material that electrically connects the first wiring portion and the second wiring portion in series;
Equipped with
The line width of the hot wire portion is 0.05 mm to 0.5 mm,
The hot wire portion has a plurality of vertically extending portions and a plurality of horizontally extending portions, and is formed by alternately connecting the vertically extending portions and the horizontally extending portions. Ori,
The horizontally extending portion is arranged to cross the information acquisition area,
The part extending in the vertical direction is arranged outside the information acquisition area,
A windshield in which at least a portion of the first wiring section and the second wiring section are formed in a waveform. The heating wire is
a first terminal portion connected to the positive electrode of the power source;
a second terminal portion connected to the negative electrode of the power source;
Furthermore,
The windshield according to claim 1, wherein the first terminal portion and the second terminal portion are arranged near an upper edge of the glass plate. The windshield according to claim 2, wherein the widths of the first wiring part and the second wiring part are larger than the width of the hot wire part. The windshield according to any one of claims 1 to 3, wherein the hot wire portion is covered with a covering material made of a dark ceramic layer. further comprising a mask layer laminated on the glass plate and having an opening in a portion corresponding to the information acquisition area,
The windshield according to any one of claims 1 to 4, wherein the hot wire portion is arranged to cross the opening. further comprising a mask layer laminated on the glass plate and having an opening in a portion corresponding to the information acquisition area,
The first wiring part and the second wiring part are arranged outside the opening and along the opening,
The windshield according to claim 3, wherein the horizontally extending portion of the hot wire portion is arranged to cross the opening. The windshield according to any one of claims 1 to 6, wherein the information acquisition area is covered with a bracket. The windshield according to any one of claims 1 to 7, wherein the hot wire portion is formed on the glass plate by printing. One of the anti-fogging means is
a base material having a first surface and a second surface, and the hot wire portion is disposed on the first surface;
an adhesive material disposed on the other surface of the base material;
Equipped with
The windshield according to any one of claims 1 to 7, wherein the base material is placed on the glass plate via the adhesive material.