JP7368944B2 - 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 therein.

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. A laser radar or a camera is generally placed inside a windshield and performs 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. The purpose of the present invention is to provide a windshield that can perform accurate information processing.

Item 1. An information acquisition device that acquires information from outside the vehicle by emitting and/or receiving light is a windshield that can be attached via a bracket,
an outer glass plate,
an inner glass plate disposed opposite to the outer glass plate;
an interlayer film disposed between the outer glass plate and the inner glass plate;
a heating element provided on the vehicle-inward surface of the inner glass plate;
Equipped with
A windshield, wherein at least a portion of the heating element is disposed on a vehicle-inward side surface of the inner glass plate at a position covered by the bracket.

Item 2. Item 2. The windshield according to Item 1, further comprising an anti-fog means provided on the heating element.

Item 3. Item 3. The windshield according to item 1 or 2, further comprising a cover member provided on the vehicle-inward side surface of the inner glass plate and covering at least a portion of the heating element.

Item 4. 4. The windshield according to item 3, wherein the cover member is provided between the heating element and the anti-fog means.

Item 5. 5. The windshield according to item 3 or 4, wherein the cover member has a lower thermal conductivity than both the glass plates.

Item 6. further comprising a shielding layer having an opening through which the light passes, and disposed on at least the vehicle-inward surface of the inner glass plate among the vehicle-inward surface of the inner glass plate and the vehicle-inward surface of the outer glass plate. Prepare,
6. The windshield according to any one of Items 3 to 5, wherein the cover member is disposed inside the opening.

Section 7. further comprising a shielding layer having an opening through which the light passes, and disposed on at least the vehicle-inward surface of the inner glass plate among the vehicle-inward surface of the inner glass plate and the vehicle-inward surface of the outer glass plate. Prepare,
6. The windshield according to any one of Items 3 to 5, wherein at least a portion of the cover member is arranged so as to protrude from a periphery of the opening.

Section 8. further comprising a shielding layer having an opening through which the light passes, and disposed on at least the vehicle-inward surface of the inner glass plate among the vehicle-inward surface of the inner glass plate and the vehicle-inward surface of the outer glass plate. Prepare,
6. The windshield according to any one of Items 3 to 5, wherein the heating element has a heating wire, and at least a portion of the heating wire is arranged to pass through the opening.

Item 9. Item 9. The windshield according to Item 8, wherein the heating element is covered by the cover member.

Item 10. Item 9. The windshield according to Item 8, wherein at least a portion of the peripheral edge of the heating element is not covered with the cover member.

Item 11. 11. The windshield according to any one of Items 8 to 10, wherein at least a part of the heating wire has a line width of 0.5 mm or less at a portion passing through the opening.

Item 12. At least a portion of the heating wires passing through the opening are arranged substantially in parallel,
11. The windshield according to any one of Items 8 to 10, wherein in the heating wire, an interval between substantially parallel portions of the opening is 1 mm or more.

Item 13. The heating wire has at least one bent part,
13. The windshield according to any one of Items 8 to 12, wherein the bent portion is formed in a curved shape.

Section 14. 14. The windshield according to item 13, wherein the line width of the bent portion is thicker than the line width of a portion of the heating wire other than the bent portion.

Item 15. 15. The windshield according to any one of Items 8 to 14, wherein, in the heating wire, at least a portion of the heating wire inside the opening has a line width narrower than an average line width of the heating wire outside the opening.

Section 16. 16. The windshield according to any one of Items 8 to 15, wherein the heating element is configured by two or more parallel circuits.

Section 17. Item 17. The windshield according to item 16, wherein the opening has an area of 7000 mm ² or more.

Section 18. 18. The windshield according to item 16 or 17, wherein the resistance value of each of the parallel circuits is within ±30% of the average of the resistance values of the two or more parallel circuits.

Item 19. The line width of the portion extending outward from the opening is adjusted so that the resistance value of each of the parallel circuits is within ±30% of the average resistance value of the two or more parallel circuits. The windshield according to item 16 or 17.

Section 20. Item 18. The windshield according to Item 16 or 17, wherein, in the heating wires in each of the parallel circuits, a wire length ratio of a portion disposed inside the opening is within 30%.

Section 21. 21. The windshield according to any one of Items 1 to 20, wherein the heating wire is printed on the vehicle-inward side surface of the inner glass plate.

Section 22. 22. The windshield according to claim 2, wherein the anti-fog means includes an anti-fog film made of a water-absorbing resin.

Section 23. 23. The windshield according to item 22, further comprising a base film on which the anti-fog film is disposed, and an adhesive layer provided on a surface of the base film opposite to the anti-fog film.

Section 24. 24. The windshield according to item 23, wherein the base film constitutes the cover member.

Section 25. 23. The windshield according to any one of Items 3 to 22, wherein the cover member has an adhesive layer.

Section 26. 26. The windshield according to item 25, wherein the adhesive layer has a thickness greater than the thickness of the heating element and 20 times or less the thickness.

Section 27. 28. The windshield according to item 26 or 27, wherein the thickness of the adhesive layer is greater than the thickness of the shielding layer and 20 times or less the thickness.

Section 28. Item 28. The windshield according to any one of items 25 to 27, wherein the adhesive layer has a shear storage modulus at 20° C. of 1.0×10 ³ GPa or more and 1.0×10 ⁷ GPa or less.

Section 29. 29. The windshield according to any one of Items 25 to 28, wherein the adhesive layer has an adhesive force of 0.25 N/10 mm or more and 12 N/mm or less.

Section 30. Item 30. The windshield according to any one of Items 25 to 29, wherein the cover member has a thickness of 25 μm or more and 200 μm or less.

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.

FIG. 1 is a plan view showing an embodiment of a windshield according to the present invention. FIG. 2 is a cross-sectional view of FIG. 1; It is a sectional view of laminated glass. FIG. 1 is a block diagram showing a schematic configuration of an in-vehicle system. It is a top view showing a heating wire. It is a sectional view showing laminated glass in which heating wires and an anti-fog sheet are laminated. FIG. 2 is a cross-sectional view of an anti-fog laminate. 3 is a graph showing the temperature of the inner glass plate according to Examples 1 and 2.

First, the configuration of the windshield according to this embodiment will be explained using FIGS. 1 and 2. FIG. 1 is a plan view of the windshield, and FIG. 2 is a sectional view of FIG. 1. For convenience of explanation, the up and down directions in FIG. 1 will be referred to as "up and down," "vertical," and "vertical," and the left and right directions in FIG. 1 will be referred to as "left and right." FIG. 1 illustrates an example of a windshield seen from inside a vehicle. That is, the back side of the paper in FIG. 1 is the outside of the vehicle, and the front side of the paper in FIG. 1 is the inside of the vehicle.

This windshield includes a substantially rectangular laminated glass 10, and is installed on the vehicle body in an inclined state. A mask layer 110 is provided on the inner surface of the laminated glass 10 facing toward the inside of the vehicle. The mask layer 110 blocks the view from outside the vehicle. There is. However, the photographing device 2 is a camera for photographing the situation outside the vehicle. Therefore, a photographing window (opening) 113 is provided in the mask layer 110 at a position corresponding to the photographing device 2, and through this photographing window 113, the photographing device 2 placed inside the vehicle can photograph the situation outside the vehicle. It has become.

An image processing device 3 is connected to the photographing device 2, and the photographed images acquired by the photographing device 2 are processed by this image processing device 3. The photographing device 2 and the image processing device 3 constitute an in-vehicle system 5, and the in-vehicle system 5 can provide various information to passengers according to the processing of the image processing device 3.

Further, as shown in FIG. 6, which will be described later, a heating wire 6 is arranged on the vehicle-inward surface of the windshield in an area corresponding to the photographing window 113. It is designed to prevent fogging and de-ice. Furthermore, as shown in FIG. 6, which will be described later, an anti-fog sheet 7 is attached to the vehicle-inward surface of the windshield so as to cover the heating wire 6. In addition, in FIG. 2, the heating wire 6 and the anti-fog sheet 7 are omitted. Each component will be explained below.

<1. Laminated glass>
FIG. 3 is a cross-sectional view of the laminated glass. As shown in the figure, this laminated glass 10 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. These configurations will be explained below.

<1-1. Glass plate>
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 TiO ₂ is 0 to 2% by mass, the ratio of TiO ₂ is 0 to 0.5% by mass, and the glass framework components (mainly SiO ₂ and Al ₂ O ₃ ) are replaced with T-Fe ₂ O ₃ and CeO ₂ and TiO ₂ can be reduced by the increment of 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

Although the thickness of the laminated glass according to this embodiment is not particularly limited, the total thickness of the outer glass plate 11 and the inner glass plate 12 can be, for example, 2.1 to 6 mm, and 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 3.8 mm, more preferably 2.6 to 3.4 mm, and 2.7 to 3.2 mm. It is particularly preferable that 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 2.0 mm, preferably 0.8 to 1.6 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.

Here, an example of a method for measuring the thickness when the glass plates 11 and 12 (laminated glass 10) are curved will be described. First, 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. Intermediate 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 being formed of a plurality of layers as described above.

<2. Mask layer＞
Next, the mask layer 110 will be explained. As illustrated in FIGS. 1 and 2, in the present embodiment, the mask layer 110 is laminated on the inner surface of the laminated glass 10 on the inside of the vehicle (the inner surface of the inner glass plate 12), and extends along the peripheral edge of the laminated glass 10. It is formed by Specifically, as illustrated in FIG. 1, the mask layer 110 according to the present embodiment includes a peripheral area 111 along the peripheral edge of the laminated glass 10 and a rectangular shape protruding downward from the upper side of the laminated glass 10. It can be divided into two protruding regions 112. The peripheral area 111 blocks the incidence of light from the peripheral edge of the windshield. On the other hand, the protruding area 112 prevents the photographing device 2 placed inside the vehicle from being seen from outside the vehicle.

However, if the mask layer 110 blocks the photographing range of the photographing device 2, the photographing device 2 will no longer be able to photograph the situation outside and in front of the vehicle. Therefore, in this embodiment, a trapezoidal photographing window 113 is provided in the protruding region 112 of the mask layer 110 at a position corresponding to the photographing device 2 so that the photographing device 2 can photograph the situation outside the vehicle. . That is, the photographing window 113 is provided independently from the non-shielding region 120 which is inside the mask layer 110 in the plane direction. Further, this photographing window 113 is an area where the material of the mask layer 110 is not laminated, and since the laminated glass has the above-mentioned visible light transmittance, it is possible to photograph the situation outside the vehicle. Note that the size of the photographing window 113 is not particularly limited, but may be, for example, 7000 mm ² or more.

In addition to being laminated on the inner surface of the inner glass plate 12 as described above, the mask layer 110 can also be laminated on the inner surface of the outer glass plate 11 and the outer surface of the inner glass plate 12, for example. Moreover, it can also be laminated at two locations, the inner surface of the outer glass plate 11 and the inner surface of the inner glass plate 12.

Next, the material of the mask layer 110 will be explained. The material of this mask layer 110 may be appropriately selected depending on the embodiment as long as it can shield the field of view from outside the vehicle. For example, a dark-colored ceramic such as black, brown, gray, or dark blue may be used. Good too.

When black ceramic is selected as the material for the mask layer 110, for example, black ceramic is laminated on the peripheral edge of the inner surface of the inner glass plate 12 by screen printing or the like, and the laminated ceramic is heated together with the inner glass plate 12. . Thereby, the mask layer 110 can be formed on the peripheral edge of the inner glass plate 12. Further, when printing black ceramic, a region where black ceramic is not printed is provided. Thereby, the photographing window 113 can be formed. Note that various ceramic materials can be used for the mask layer 110. For example, a ceramic having a composition shown in Table 1 below can be used for the mask layer 110.

*1, Main ingredients: copper oxide, chromium oxide, iron oxide and manganese oxide *2, Main ingredients: bismuth borosilicate, zinc borosilicate

<3. In-vehicle system＞
Next, the in-vehicle system 5 including the photographing device (information acquisition device) 2 and the image processing device 3 will be described using FIG. 4. FIG. 4 illustrates the configuration of the in-vehicle system 5. As illustrated in FIG. 4, the in-vehicle system 5 according to the present embodiment includes the photographing device 2 and an image processing device 3 connected to the photographing device 2.

The image processing device 3 is a device that processes photographed images acquired by the photographing device 2. The image processing device 3 has, for example, general hardware such as a storage section 31, a control section 32, an input/output section 33, etc., which are connected via a bus. However, the hardware configuration of the image processing device 3 is not limited to this example, and components may be added or omitted as appropriate depending on the embodiment with respect to the specific hardware configuration of the image processing device 3. and can be added.

The storage unit 31 stores various data and programs used in the processing executed by the control unit 32 (not shown). The storage unit 31 may be realized by, for example, a hard disk or a recording medium such as a USB memory. Further, the various data and programs stored in the storage unit 31 may be obtained from a recording medium such as a CD (Compact Disc) or a DVD (Digital Versatile Disc). Furthermore, the storage unit 31 may be called an auxiliary storage device.

As described above, the laminated glass 10 is arranged in an inclined position with respect to the vertical direction and is curved. Then, the photographing device 2 photographs the situation outside the vehicle through such laminated glass 10. Therefore, the photographed image acquired by the photographing device 2 is deformed depending on the attitude, shape, refractive index, optical defects, etc. of the laminated glass 10. Further, aberrations inherent to the camera lens of the photographing device 2 are also added. Therefore, the storage unit 31 may store correction data for correcting an image deformed by such aberrations of the laminated glass 10 and the camera lens.

The control unit 32 includes one or more processors such as a microprocessor or a CPU (Central Processing Unit), and peripheral circuits (ROM (Read Only Memory), RAM (Random Access Memory), and interface circuits) used for processing of this processor. etc.) and has. ROM, RAM, etc. may be called a main memory in the sense that they are arranged in the address space handled by the processor in the control unit 32. The control unit 32 functions as the image processing unit 321 by executing various data and programs stored in the storage unit 31.

The image processing unit 321 processes the photographed image acquired by the photographing device 2. Processing of photographed images can be selected as appropriate depending on the embodiment. For example, the image processing unit 321 may recognize the subject in the captured image by analyzing the captured image using pattern matching or the like. In this embodiment, since the photographing device 2 photographs the situation in front of the vehicle, the image processing unit 321 further determines whether or not a living creature such as a human being is photographed in front of the vehicle based on the subject recognition. Good too. If a person is shown in front of the vehicle, the image processing unit 321 may output a warning message using a predetermined method. Further, for example, the image processing unit 321 may perform predetermined processing on the captured image. The image processing unit 321 may then output the processed photographed image to a display device (not shown) such as a display connected to the image processing device 3.

The input/output unit 33 is one or more interfaces for transmitting and receiving data to and from devices existing outside the image processing device 3 . The input/output unit 33 is, for example, an interface for connecting to a user interface or an interface such as a USB (Universal Serial Bus). Note that in this embodiment, the image processing device 3 is connected to the photographing device 2 via the input/output unit 33, and acquires a photographed image photographed by the photographing device 2.

Such an image processing device 3 may be a general-purpose device such as a PC (Personal Computer) or a tablet terminal, in addition to a device designed specifically for the provided service.

Further, the photographing device 2 is attached to a bracket (not shown), and this bracket 110 is attached to the mask layer. Therefore, in this state, the attachment of the photographing device 2 to the bracket and the attachment of the bracket to the mask layer 110 are adjusted so that the optical axis of the camera of the photographing device 2 passes through the photographing window 113. Further, a cover (not shown) is attached to the bracket so as to cover the photographing device 2. Therefore, the photographing device 2 is placed in a space surrounded by the laminated glass 10, the bracket, and the cover, and is not visible from inside the vehicle, and only a part of the photographing device 2 is visible from the outside of the vehicle through the photographing window 113. There is no such thing. The photographing device 2 and the above-mentioned input/output unit 33 are connected by a cable (not shown), which is pulled out from the cover and connected to the image processing device 3 placed at a predetermined position inside the vehicle. .

<4. Heating wire>
Next, the heating wire 6 will be explained with reference to FIGS. 5 and 6. As shown in FIGS. 5 and 6, the heating wire 6 passes through the photographing window 113 by means of a first heating wire 61, a second heating wire 62, and a connecting wire 63. It is located in To explain in more detail, the first heating wire 61 and the second heating wire 62 are connected in parallel and arranged to pass through the imaging window 113. The first heating wire 61 is arranged so as to pass through the upper part of the photographing window 113, and the second heating wire 62 is arranged so as to pass through the lower part of the photographing window 113. Moreover, both heating wires 61 and 62 extend in an oblique direction that intersects with the horizontal direction.

The first heating wire 61 passes through the imaging window 113 and connects a plurality of main parts 611 arranged in parallel, and a plurality of connections arranged outside the imaging window 113 and connecting the ends of the adjacent main parts 611. 612. That is, the first heating wire 61 is arranged so as to reciprocate around the photographing window 113 a plurality of times by combining the plurality of main parts 611 and the connecting parts 612. Although the interval between adjacent main parts 611 is not particularly limited, it is preferably 1 mm or more, and more preferably 5 mm or more, for example. In particular, it is preferable that the interval between the main portions 611 of the heating wires 6 is at least 20 times the line width. This is due to the balance between the line width and spacing of the heating lines. For example, if the line width is made small, the resistance value will increase and sufficient heat generation cannot be obtained under a constant voltage.If the interval between the heating wires 6 is made small, the view from the photographing device 2 will be blocked. This is because it may affect the visual field. A first connecting terminal 64 and a second connecting terminal 65 are connected to both ends of the first heating wire 61 via the connecting wire 63. The connection wire 63 is a conducting wire having a larger line width than the first heating wire 61 . The connection terminals 64 and 65 may be fixed directly to the connection wire 63 with solder or the like, or a rectangular or circular area may be formed at the end of the connection wire 63 and the connection terminals 64 and 65 may be fixed to the end of the connection wire 63. It can also be fixed. Note that power supply conductive wires are connected to the connection terminals 64 and 65 by solder or the like, and a power supply voltage of, for example, 10 to 50V is applied thereto.

The first connection terminal 64 and the second connection terminal 65 are arranged at a position apart from the imaging window 113, but both are arranged on the mask layer 110. Further, the connection line 63 is also arranged on the mask layer 110.

Although the connecting portion 612 is formed in a U-shape, it can also be formed in a curved shape as a whole. This is because if the connecting portion 612 is provided with a sharp corner (bent portion), abnormal heat generation may occur. Therefore, it is preferable to form such corner portions (bent portions) into curved shapes. Note that it is preferable that not only the connecting portion 612 but also the corner portion (bent portion) provided on the heating wire 6 be formed in a curved shape. Further, as shown in FIG. 5, the line width of the connecting portion 612 can be made thicker than the line width of the main portion 611. As a result, the resistance value at the connecting portion 612 can be reduced, and thus abnormal heat generation can also be suppressed. However, the connecting portion 612 and the main portion 611 may have the same line width.

The second heating wire 62 is also configured similarly to the first heating wire 61. That is, a plurality of main parts 621 that pass through the photographing window 113 and are arranged in parallel are combined with a plurality of connecting parts 622 that are arranged outside the photographing window 113 and connect the ends of the adjacent main parts 621. It consists of: That is, the second heating wire 62 is also arranged to reciprocate around the imaging window 113 multiple times by combining the multiple main portions 621 and the connecting portions 622. Note that the main portion 621 of the second heating wire 62 is arranged parallel to the main portion 611 of the first heating wire 61. Both ends of the second heating wire 62 are connected to a first connecting terminal 64 and a second connecting terminal 65 via the connecting wire 63. Therefore, the first heating wire 61 and the second heating wire 62 are connected in parallel to the two connection terminals 64 and 65, and each constitutes a parallel circuit. For example, when the area of the photographing window 113 is large, the length of the main parts 611, 612 becomes long, so there is a possibility that the amount of heat generated by the main parts may be small. Therefore, when the heating wire 6 is configured with a plurality of parallel circuits, the lengths of the first heating wire 61 and the second heating wire 62 are shortened, so that a sufficient amount of heat can be obtained. Note that when the applied voltage is constant, sufficient current can be passed by reducing the resistance value. As a result, a sufficient amount of heat can be obtained. Further, it is preferable that the resistance value of each parallel circuit is within ±30% of the average resistance value of all the parallel circuits. For this purpose, it is necessary to adjust the line width and length of the heating wire 6 as described below.

That is, the line width of the heating wire 6 can be changed in various ways. For example, by making the average line width of the first heating wire 61 and the second heating line 62 smaller than the average line width of the connection line 63, the resistance value of the connection line 63 becomes smaller, so that heat generation in the connection line 63 is reduced. can be made smaller. Thereby, the temperature outside the photographing window 113 can be made lower than the temperature inside the photographing window 113, and the temperature gradient from the outside to the inside of the photographing window 113 can be made gentler. As a result, cracking of the glass plates 1 and 2 can be prevented. Alternatively, as described above, the average line width of the main portions 611, 621 of the first heating wire 61 and the second heating wire 62 can be made smaller than the average line width of the connecting portions 612, 622 and the connecting line 63. . In other words, in order to uniformly heat the main parts 611 and 612 that require heating, by adjusting the line width of the connecting parts (including bent parts) 612 and 622, the current flowing in the parallel circuit can be made uniform. Therefore, the inside of the photographing window 113 can be heated uniformly. Further, the lengths of the main parts 611, 621 of the first heating wire 61 and the second heating wire 62 can be adjusted. (including the connection line 63) can be adjusted to within 30% of the length. In this way, in particular, by making the lengths of the main portions 611 and 612 of the heating wires the same, it becomes easier to equalize the resistance value of the entire circuit, thereby making it easier to heat uniformly.

Furthermore, if the length of the connecting wire 63 is increased, the resistance of this portion increases, so that the amount of heat generated can be adjusted. That is, the amount of heat generated in the first and second heating wires 61 and 62 can be adjusted to be smaller.

The line width of the heating line 6 is, for example, preferably 1 to 500 μm, more preferably 1 to 400 μm. Furthermore, it is preferably 1 to 300 μm. This is because the smaller the line width, the harder it is to visually recognize the line, which is suitable for the photographing window 113. In particular, it is preferable that the line width of the main portions 611, 621 of each heating wire 61, 62 be within the above range. On the other hand, if the line width is too small, manufacturing may not be possible. Furthermore, when the voltage applied to the parallel circuit is constant, if the line width is too small, the resistance will increase, and as a result, the current flowing through the circuit will become small, making it impossible to heat the circuit sufficiently. Note that this line width refers to the line width of the largest portion of the cross-sectional shape of the heating wire 314. For example, when the cross-sectional shape of the heating wire 6 is a trapezoid, the width of the lower side is the line width, and when the cross-sectional shape of the heating wire 6 is circular, the diameter is the line width. The width of the heating wire 6 can be measured, for example, using a microscope such as VHX-200 (manufactured by Keyence Corporation) with a magnification of 1000 times.

The thickness of the heating wire 6 is preferably equal to or less than the line width. In other words, it is preferable that the aspect ratio of the cross section of the heating wire 6 is 1 or less. This is because if the thickness of the heating wire 6 becomes larger than the line width, the heating wire 6 may fall down on the inner glass plate 12, making manufacturing difficult, or there is a risk of wire breakage.

The heating wire 6 can be made of various materials, such as copper (or tin-plated copper), gold, aluminum, magnesium, cobalt, tungsten, silver, etc. Among these, it is particularly preferable to use silver, copper, gold, and aluminum, which are materials with an electrical resistivity of 3.0×10 ⁻⁸ Ωm or less. The heating wire 6 is formed, for example, by printing such as screen printing. That is, the heating wire 6 is formed by applying silver paste or the like by printing and then drying it. All parts of the heating wire 6 may be integrally formed by printing or the like, or, for example, only the connection terminals 64 and 65 may be formed by pasting separate members.

The heating wire 6 configured as described above is covered by a bracket and its cover so that it cannot be seen from inside the vehicle. Moreover, since it is placed on the mask layer 110, it is not visible from outside the vehicle. Note that all 6 of the heating wires do not need to be covered by the bracket and the cover, and at least a portion corresponding to the photographing window 113 may be covered by the bracket and the cover. Alternatively, only a portion of the connection terminals 64, 65 and the connection wire 63 may protrude from the bracket. However, in order to prevent contact from inside the vehicle, it is preferable that all of the heating wires 6 be covered with a bracket or a cover. Note that, for example, even if a part of the heating wire 6 protrudes from the bracket, it only needs to be covered with a cover.

<5. Anti-fog sheet＞
Next, the anti-fog sheet 7 will be explained. As mentioned above, the anti-fog sheet 7 is attached to the photographing window 113, and in particular, in this embodiment, the anti-fog sheet 7 is attached so as to cover the heating wire 6, as shown in FIG. It is pasted. Note that the entire heating wire 6 does not need to be covered with the anti-fog sheet 7, and at least a portion corresponding to the photographing window 113 may be covered with the anti-fog sheet 7. Alternatively, the anti-fog sheet 7 may be attached to the portion covered by the bracket and cover.

As shown in FIG. 7, an adhesive layer 71, a base film 72, and an anti-fog layer (anti-fog means) 73 are laminated in this order until it is fixed to the photographing window 113. Further, a removable first protective sheet 74 is attached to the adhesive layer 71, and a releasable second protective sheet 75 is attached to the anti-fog layer 73, and these five layers constitute an anti-fog laminate. . Further, the anti-fog sheet 7 is formed in a shape corresponding to the photographing window 113, but can be formed into a shape slightly smaller than the photographing window 113, for example. Alternatively, it can be formed to be larger than the photographing window 113 and to extend beyond the photographing window 113 and cover a part of the mask layer 110. In this case, it is particularly preferable that the heating wire be disposed so as to cover the first heating wire 61 and the second heating wire 62. Further, the anti-fog sheet 7 may be made larger to cover the connection wire 63. Each layer will be explained below.

<5-1. Anti-fog layer＞
The anti-fog layer is not particularly limited as long as it has an anti-fog effect on the laminated glass plate 10, and any known layer can be used. In general, anti-fog layers are of 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, a water-repellent type that prevents water droplets from condensing on the surface, and a water-repellent type that prevents water droplets from condensing on the surface. There is a water-repellent type, but any type of anti-fog layer can be applied. Below, as an example, an example of a water-repellent and water-absorbing type anti-fogging layer will be described.

[Organic-inorganic composite anti-fog layer]
The organic-inorganic composite antifogging layer is a single layer film or a laminated multilayer film formed on the surface of the base film. The organic-inorganic composite antifogging layer contains at least a water-absorbing resin, a water-repellent group, and a metal oxide component. The antifogging film may further contain other functional components as required. The water-absorbing resin may be of any type as long as it can absorb and retain water. The water-repellent group can be supplied to the antifogging film from a metal compound having a water-repellent group (a metal compound containing a water-repellent group). The metal oxide component can be supplied to the antifogging film from water-repellent group-containing metal compounds, other metal compounds, metal oxide fine particles, and the like. 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 layer 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 layer 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 hinders film formation. 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 layer 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 layer has a water-absorbing resin as a 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 layer is preferably 50% by weight or more, more preferably 60% by weight or more, particularly preferably 65% by weight, from the viewpoints of film hardness, water absorption, and antifogging properties. It is at least 95% by weight, more preferably at most 90% by weight.

(water repellent group)
In order to fully obtain the above-mentioned effects of the water-repellent group, it is preferable to use a water-repellent group with high water repellency. Preferred water-repellent groups are (1) a chain or cyclic alkyl group having 3 to 30 carbon atoms, and (2) a chain or cyclic alkyl group having 1 to 30 carbon atoms in which at least a portion of the hydrogen atoms are replaced with fluorine atoms. At least one type selected from alkyl groups (hereinafter sometimes referred to as "fluorine-substituted alkyl groups").

Regarding (1) and (2), the chain or cyclic alkyl group is preferably a chain alkyl group. The chain alkyl group may be a branched alkyl group, but is preferably a straight chain alkyl group. An alkyl group having more than 30 carbon atoms may cause the antifogging film to become cloudy. From the viewpoint of the balance between antifogging properties, strength, and appearance of the film, the number of carbon atoms in the alkyl group is preferably 20 or less, more preferably 6 to 14. Particularly preferred alkyl groups are linear alkyl groups having 6 to 14 carbon atoms, especially straight chain alkyl groups having 6 to 12 carbon atoms, such as n-hexyl group (6 carbon atoms), n-decyl group (10 carbon atoms), n-dodecyl group ( The number of carbon atoms is 12). Regarding (2), the fluorine-substituted alkyl group may be a group in which only some of the hydrogen atoms of a chain or cyclic alkyl group are substituted with fluorine atoms, or all of the hydrogen atoms in a chain or cyclic alkyl group are substituted with fluorine atoms. It may also be a group in which is substituted with a fluorine atom, such as a linear perfluoroalkyl group. Since the fluorine-substituted alkyl group has high water repellency, a sufficient effect can be obtained by adding a small amount. However, if the content of the fluorine-substituted alkyl group becomes too large, it may separate from other components in the coating solution for forming a film.

(Hydrolyzable metal compound with water-repellent group)
In order to incorporate a water-repellent group into an antifogging film, a metal compound having a water-repellent group (a metal compound containing a water-repellent group), especially a metal compound having a water-repellent group and a hydrolyzable functional group or a halogen atom ( A hydrolyzable metal compound containing a water-repellent group) or a hydrolyzate thereof may be added to a coating liquid for forming a film. In other words, the water-repellent group may be derived from a hydrolyzable metal compound containing a water-repellent group. As the water-repellent group-containing hydrolyzable metal compound, a water-repellent group-containing hydrolyzable silicon compound represented by the following formula (I) is suitable.
R _m SiY _4-m (I)
Here, R is a water-repellent group, that is, a chain or cyclic alkyl group having 1 to 30 carbon atoms, in which at least some of the hydrogen atoms may be substituted with fluorine atoms, and Y is a hydrolyzable functional group. group or a halogen atom, and m is an integer of 1 to 3. The hydrolyzable functional group is, for example, at least one selected from an alkoxyl group, an acetoxy group, an alkenyloxy group, and an amino group, and is preferably an alkoxy group, particularly an alkoxy group having 1 to 4 carbon atoms. An alkenyloxy group is, for example, an isopropenoxy group. The halogen atom is preferably chlorine. Note that the functional groups exemplified here can also be used as "hydrolyzable functional groups" described below. m is preferably 1-2.

The compound represented by formula (I) provides a component represented by formula (II) below when hydrolysis and polycondensation proceed completely.
R _m SiO _(4-m)/2 (II)
Here, R and m are as described above. After hydrolysis and polycondensation, the compound represented by formula (II) actually forms a network structure in which silicon atoms are bonded to each other via oxygen atoms in the antifogging film.

As described above, the compound represented by formula (I) is hydrolyzed or partially hydrolyzed, and furthermore, at least a portion thereof is polycondensed, so that silicon atoms and oxygen atoms are alternately connected and three-dimensionally. Forms a network structure of expanding siloxane bonds (Si-O-Si). A water-repellent group R is connected to the silicon atoms included in this network structure. In other words, the water-repellent group R is fixed to the network structure of siloxane bonds via the bond R--Si. This structure is advantageous in uniformly dispersing the water-repellent groups R in the film. The network structure may contain a silica component supplied from a silicon compound (eg, tetraalkoxysilane, silane coupling agent) other than the water-repellent group-containing hydrolyzable silicon compound represented by formula (I). To form an antifogging film using a silicon compound that does not have a water repellent group and has a hydrolyzable functional group or a halogen atom (hydrolyzable silicon compound that does not contain a water repellent group) together with a hydrolyzable silicon compound that contains a water repellent group. When blended into a coating liquid, a network structure of siloxane bonds can be formed that includes silicon atoms bonded to water-repellent groups and silicon atoms not bonded to water-repellent groups. With such a structure, it becomes easy to adjust the water-repellent group content and the metal oxide component content in the antifogging film independently of each other.

The water-repellent group has the effect of improving the anti-fog performance by improving the permeability of water vapor on the surface of the anti-fog film containing the water-absorbing resin. Since the two functions of water absorption and water repellency are contradictory to each other, water-absorbing materials and water-repellent materials have conventionally been added to separate layers, but water-repellent groups are applied near the surface of the anti-fog layer. Eliminates uneven distribution of water, prolongs the time until dew condensation, and improves the anti-fog properties of an anti-fog film having a single layer structure. The effect will be explained below.

Water vapor that has entered the antifogging film containing a water-absorbing resin forms hydrogen bonds with the hydroxyl groups of the water-absorbing resin and is retained in the form of bound water. As the amount increases, water vapor is retained in the form of bound water, semi-bound water, and finally in the form of free water retained in the voids in the antifogging film. In the antifogging film, the water-repellent group prevents the formation of hydrogen bonds and facilitates the dissociation of the formed hydrogen bonds. If the content of the water-absorbing resin is the same, there is no difference in the number of hydroxyl groups capable of hydrogen bonding in the film, but water-repellent groups reduce the rate of hydrogen bond formation. Therefore, in an antifogging film containing a water-repellent group, water will eventually be retained in the film in one of the above forms, but by the time it is retained, it remains as water vapor all the way to the bottom of the film. Can be spread. Furthermore, once retained water is relatively easily dissociated and easily moves to the bottom of the membrane in the form of water vapor. As a result, the distribution of the amount of water retained in the thickness direction of the membrane becomes relatively uniform from near the surface to the bottom of the membrane. In other words, the entire thickness of the antifogging film can be effectively utilized to absorb water supplied to the film surface, making it difficult for water droplets to condense on the surface, resulting in high antifogging properties. Furthermore, since water droplets are less likely to condense on the surface, an antifogging film that has absorbed moisture has the characteristic of being less likely to freeze even at low temperatures. Therefore, by fixing this antifogging film to the photographing window 113, the visibility of the photographing window 113 can be ensured over a wide temperature range.

On the other hand, in an antifogging film that does not contain a water-repellent group, water vapor that has entered the film is very easily retained in the form of bound water, semi-bound water, or free water. Therefore, the invading water vapor tends to be retained near the surface of the membrane. As a result, the water content in the membrane is extremely high near the surface and rapidly decreases toward the bottom of the membrane. In other words, although water can still be absorbed at the bottom of the membrane, the area near the surface of the membrane becomes saturated with moisture and condenses as water droplets, resulting in limited antifogging properties.

When a water-repellent group is introduced into an antifogging film using a hydrolyzable silicon compound containing a water-repellent group (see formula (I)), a strong network structure of siloxane bonds (Si--O--Si) is formed. Formation of this network structure is advantageous from the viewpoint of improving not only wear resistance but also hardness, water resistance, and the like.

The water-repellent group may be added in such an amount that the contact angle of water on the surface of the antifogging film is 70 degrees or more, preferably 80 degrees or more, more preferably 90 degrees or more. For the contact angle of water, a value measured by dropping a 4 mg water droplet onto the surface of the membrane is adopted. Particularly when using a methyl group or an ethyl group, which has a rather weak water repellency, as a water repellent group, it is preferable to incorporate the water repellent group into the antifogging film in an amount such that the contact angle of water falls within the above range. The upper limit of the contact angle of this water droplet is not particularly limited, but is, for example, 150 degrees or less, for example, 120 degrees or less, and even 100 degrees or less. It is preferable that the water-repellent group is uniformly contained in the anti-fog film so that the contact angle of the water droplets falls within the above-mentioned range in all areas of the surface of the anti-fog film.

The antifogging film should be 0.05 parts by mass or more, preferably 0.1 parts by mass or more, more preferably 0.3 parts by mass or more, based on 100 parts by mass of the water-absorbent resin, and 10 parts by mass or more. It is preferable that the water-repellent group is contained in an amount of not more than 5 parts by mass, preferably not more than 5 parts by mass.

(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 layer 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 oxide is a necessary component to ensure the strength, especially wear resistance, of the organic-inorganic composite anti-fog layer, but when its content increases, the anti-fog property of the organic-inorganic composite anti-fog layer decreases. .

(Inorganic oxide fine particles)
The organic-inorganic composite antifogging layer may further contain inorganic oxide fine particles as at least a portion 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 layer 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 layer to an article supporting the organic-inorganic composite anti-fog layer, 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 layer. Furthermore, when inorganic oxide fine particles are added to the organic-inorganic composite antifogging layer, 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 anti-fog layer by adding previously formed inorganic oxide fine particles to the coating liquid for forming the organic-inorganic composite anti-fog layer.

If the average particle size of the inorganic oxide fine particles is too large, the organic-inorganic composite antifogging layer 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 inorganic oxide fine particles increases, the water absorption amount of the entire organic-inorganic composite anti-fogging layer may decrease, and the organic-inorganic composite anti-fogging layer 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 without water repellent group)
The antifogging film may contain a metal oxide component derived from a hydrolyzable metal compound that does not have a water-repellent group (a hydrolyzable compound that does not contain a water-repellent group). A preferred hydrolyzable metal compound without a water-repellent group is a hydrolyzable silicon compound without a water-repellent group. The hydrolyzable silicon compound without a water-repellent group is, for example, at least one silicon compound selected from silicon alkoxide, chlorosilane, acetoxysilane, alkenyloxysilane, and aminosilane (but does not have a water-repellent group), Silicon alkoxide without a water-repellent group is preferred. Incidentally, as the alkenyloxysilane, isopropenoxysilane can be exemplified.

The hydrolyzable silicon compound having no water-repellent group may be a compound represented by the following formula (III).
_SiY4 (III)
As mentioned above, Y is a hydrolyzable functional group, and is preferably at least one selected from an alkoxyl group, an acetoxy group, an alkenyloxy group, an amino group, and a halogen atom.

The hydrolyzable metal compound containing no water-repellent group is hydrolyzed or partially hydrolyzed, and furthermore, at least a portion thereof is polycondensed to provide a metal oxide component in which a metal atom and an oxygen atom are bonded. This component can firmly bond the metal oxide fine particles and the water-absorbing resin, and can contribute to improving the abrasion resistance, hardness, water resistance, etc. of the antifogging film. The metal oxide component derived from a hydrolyzable metal compound having no water-repellent group is 0 to 40 parts by weight, preferably 0.1 to 30 parts by weight, more preferably 1 to 30 parts by weight, based on 100 parts by weight of the water-absorbing resin. The amount may be 20 parts by weight, particularly preferably 3 to 10 parts by weight, and in some cases 4 to 12 parts by weight.

A preferred example of the hydrolyzable silicone compound having no water-repellent group is tetraalkoxysilane, more specifically tetraalkoxysilane having an alkoxy group having 1 to 4 carbon atoms. Tetraalkoxysilanes include, for example, tetramethoxysilane, tetraethoxysilane, tetra-n-propoxysilane, tetraisopropoxysilane, tetra-n-butoxysilane, tetraisobutoxysilane, tetra-sec-butoxysilane and tetra-tert- At least one selected from butoxysilane.

If the content of the metal oxide (silica) component derived from tetraalkoxysilane becomes excessive, the antifogging properties of the antifogging film may decrease. One reason for this is that the flexibility of the antifogging film decreases, limiting swelling and contraction of the film due to absorption and release of moisture. The metal oxide component derived from tetraalkoxysilane is preferably added in an amount of 0 to 30 parts by weight, preferably 1 to 20 parts by weight, more preferably 3 to 10 parts by weight, per 100 parts by weight of the water-absorbing resin.

Another preferred example of a hydrolyzable silicone compound having no water-repellent group is a silane coupling agent. Silane coupling agents are silicon compounds having different reactive functional groups. It is preferable that a part of the reactive functional group is a hydrolyzable functional group. The silane coupling agent is, for example, a silicon compound having an epoxy group and/or an amino group and a hydrolyzable functional group. Examples of preferred silane coupling agents include glycidyloxyalkyltrialkoxysilane and aminoalkyltrialkoxysilane. In these silane coupling agents, the alkylene group directly bonded to the silicon atom preferably has 1 to 3 carbon atoms. Glycidyloxyalkyl groups and aminoalkyl groups contain hydrophilic functional groups (epoxy groups, amino groups), so although they contain alkylene groups, they are not water repellent as a whole.

The silane coupling agent firmly binds the water-absorbing resin, which is an organic component, and the metal oxide fine particles, which is an inorganic component, and can contribute to improving the abrasion resistance, hardness, water resistance, etc. of the antifogging film. However, when the content of the metal oxide (silica) component derived from the silane coupling agent becomes excessive, the antifogging property of the antifogging film decreases, and in some cases, the antifogging film becomes cloudy. The metal oxide component derived from the silane coupling agent is in the range of 0 to 10 parts by weight, preferably 0.05 to 5 parts by weight, and more preferably 0.1 to 2 parts by weight, based on 100 parts by weight of the water absorbent resin. It is best to add it with

(Crosslinked structure)
The antifogging film may contain a crosslinked structure derived from a crosslinking agent, preferably 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, scratch resistance, and water resistance of the antifogging film. Stated from another perspective, the introduction of the crosslinked structure facilitates improving the durability of the antifogging film without reducing its antifogging performance.

When a crosslinked structure derived from a crosslinking agent is introduced into an antifogging film whose metal oxide component is a silica component, the antifogging film contains silicon and metal atoms other than silicon, preferably boron, titanium, or zirconium, as metal atoms. May contain.

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 alkoxides, titanium chelate compounds, and titanium acylates. Examples of titanium alkoxides include titanium tetraisopropoxide, titanium tetra-n-butoxide, and titanium tetraoctoxide. Examples of titanium chelate compounds include 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 organic titanium compounds are titanium chelate compounds, especially titanium lactate.

Preferred crosslinking agents when the water-absorbing resin is polyvinyl acetal are organic titanium compounds, especially titanium lactate.

(Other optional ingredients)
Other additives may be added to the antifogging film. Examples of additives include glycols such as glycerin and ethylene glycol, which have the function of improving antifogging properties. Additives may be surfactants, leveling agents, ultraviolet absorbers, colorants, antifoaming agents, preservatives, and the like.

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

Note that the above-mentioned anti-fog layer is an example, and other known anti-fog layers may be used, such as the anti-fog layer described in JP-A No. 2001-146585, and various other anti-fog layers. .

<5-2. Base film>
The base film 72 is formed of a transparent resin film, and can be formed of, for example, polyethylene terephthalate, polyvinyl chloride, polyvinylidene chloride, polycarbonate, or acrylic resin. The resin may also contain an ultraviolet absorber. In particular, the base film 72 is preferably made of a material having a lower thermal conductivity than the glass plates 11 and 12 in order to suppress heat radiation from the heating wire 6 to the inside of the vehicle, as described later. Specifically, the thermal conductivity of the base film 72 is preferably 0.7 W/(m·K) or less, more preferably 0.5 W/(m·K) or less.

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. .

It is preferable that such a base film 72 has a transmittance of 5% or less at a wavelength of 380 nm and a transmittance of 50% or less at a wavelength of 400 nm, for example.

Moreover, since the base film 72 is a film that supports the anti-fog layer 73, it needs to have a certain degree of rigidity. Furthermore, when the thickness of the base film 72 is increased, heat transfer to the inside of the vehicle is reduced, and heat radiation to the inside of the vehicle can be suppressed, making it easier to transmit heat to the outside of the vehicle, which is advantageous for defrosting ice. However, if the thickness is too large, the haze rate tends to increase. Furthermore, it becomes difficult for the heating wire to follow the difference in level, and air tends to accumulate in the difference in level. Therefore, the thickness of the base film 72 is preferably 25 to 200 μm, for example.

<5-3. Adhesive layer＞
The adhesive layer 71 may be any layer as long as it can fix the base film 72 to the inner glass plate 12 with sufficient strength, as will be described later. Specifically, an adhesive layer such as a resin made by copolymerizing acrylic, rubber, or methacrylic and acrylic monomers that have tackiness at room temperature and set at a desired glass transition temperature can be used. As the acrylic monomer, methyl acrylate, ethyl acrylate, butyl acrylate, stearyl acrylate, 2-ethylhexyl acrylate, etc. can be used, and as the methacrylic monomer, ethyl methacrylate, butyl methacrylate, methacrylic acid can be used. Isobutyl, stearyl methacrylate, etc. can be applied. Furthermore, when performing construction by heat lamination or the like, an organic material that softens at the lamination temperature may be used. For example, in the case of a resin made by copolymerizing methacrylic and acrylic monomers, the glass transition temperature can be adjusted by changing the blending ratio of each monomer. A UV absorber may be contained in the adhesive layer.

Note that the adhesive layer 71 preferably has a thickness that can absorb the difference in level caused by the heating wire 6 and the mask layer 113. For example, the thickness of the adhesive layer 71 is preferably greater than the step between the inner glass plate 12 and the heating wire 6, that is, the thickness of the heating wire 6, and 20 times or less than the thickness of the heating wire 6. Further, the thickness of the adhesive layer 71 is preferably greater than the step between the inner glass plate 12 and the mask layer 113, that is, the thickness of the mask layer 113, and 20 times or less than the thickness of the mask layer 113. Therefore, the thickness of the adhesive layer 71 can be, for example, 1 to 300 μm. In addition, in order to make the adhesive layer easily deformable from the viewpoint of absorbing steps, the shear storage modulus of the adhesive layer 71 is set to, for example, 1.0 x 10 ³ GPa or more and 1.0 x 10 ⁷ GPa or less. be able to.

Moreover, the adhesive force of the adhesive layer 71 can be 0.25 N/10 mm or more and 12 N/mm or less, and preferably 1.0 N/10 mm or more and 10 N/mm or less. This allows the anti-fog film to be firmly attached and also to be easily peeled off and replaced.

<5-4. Protective sheet>
The first protective sheet 74 protects the adhesive layer 71 until it is fixed to the photographing window 113 of the laminated glass 10, and is made of, for example, a resin sheet coated with a release agent such as silicone. has been done. Similarly, the second protective sheet 75 is for protecting the anti-fog layer 73 until it is fixed to the photographing window of the laminated glass, and is formed of a resin sheet coated with a release agent. ing. In either case, a known general release sheet can be used.

<6. Windshield manufacturing method＞
Next, a method for manufacturing the windshield will be described. First, a mask layer 110 is laminated on at least one of the outer glass plate 11 and the inner glass plate 12 that are formed into a predetermined shape. Subsequently, these glass plates 11 and 12 are shaped to be curved. This method is not particularly limited, but can be performed by, for example, known press molding. Alternatively, after placing the outer glass plate 11 and the inner glass plate 12 on a mold, the mold is passed through a heating furnace and heated. Thereby, these glass plates 11 and 12 can be curved by their own weight.

After the outer glass plate 11 and the inner glass plate 12 are formed in this manner, a laminate in which the interlayer film 13 is sandwiched between the outer glass plate 11 and the inner glass plate 12 is subsequently formed. Note that the intermediate film 13 has a larger shape than the glass plates 11 and 12.

Next, this laminate is placed in a rubber bag and preliminarily bonded at about 70 to 110° C. while vacuum suction is applied. Other preliminary adhesion methods are also possible, and the following method may also be used. For example, the above laminate is heated in an oven at 45 to 65°C. Next, this laminate is pressed with a roll at 0.45 to 0.55 MPa. Subsequently, this laminate 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 laminate is subjected to main bonding in an autoclave, for example, at 8 to 15 atm and at 100 to 150°C. Specifically, the main bonding can be performed under conditions of, for example, 14 atm and 135°C. Through the above preliminary adhesion and main adhesion, the intermediate film 13 is adhered to each glass plate 11, 12. Subsequently, the interlayer film 13 protruding from the outer glass plate 11 and the inner glass plate 12 is cut.

Subsequently, the above-mentioned heating wire 6 is formed on the vehicle-inward side surface (including the mask layer 110) of the inner glass plate 12 by printing. Finally, the above-mentioned anti-fog sheet 7 is attached to the vehicle-inward side surface of the inner glass plate 12 (including the mask layer 110) so as to cover the heating wire 6. First, an anti-fog laminate is prepared, and the first protective sheet 74 attached to the adhesive layer 71 is removed. Then, the exposed adhesive layer 71 is pasted. Then, the second protection sheet 75 is pressed to firmly fix the anti-fog sheet 7 to the photographing window 113. Finally, when the second protective sheet 75 is removed and the anti-fog layer 73 is exposed, the attachment of the anti-fog sheet 7 is completed. Note that the timing for attaching the anti-fog sheet 7 is not particularly limited, and may be after attaching the bracket. Further, the second protection sheet 75 may be removed after the anti-fog sheet 7 is attached to the photographing window 113 and the bracket is attached.

<7. Features>
According to the windshield described above, the following effects can be obtained.
(1) Since the heating wire 6 is provided so as to pass through the photographing window 113, it is possible to prevent the laminated glass 10 from fogging in the photographing window 113. Further, the laminated glass 10 can also be thawed using the heating wire 6. Therefore, when the photographing device 2 receives light through the photographing window 113, it is possible to prevent problems such as the fogging of the photographing window 113, which obstructs the passage of light and makes it impossible to perform accurate measurements. As a result, information can be processed accurately.

(2) Since the heating wire 6 is covered by the bracket and its cover, it can be hidden from view from inside the vehicle. Further, it is possible to prevent the passenger from coming into contact with the heating wire 6.

(3) Since the anti-fog sheet 7 is also attached in addition to the heating wire 6, fogging of the laminated glass 10 can be suppressed by the anti-fog sheet 7 even if the heating wire 6 is not energized. In particular, the upper part of the vehicle interior where the photographic window 113 is provided tends to get cold and foggy even when the heating is turned on. Therefore, it is advantageous to provide the anti-fog sheet 7 at such a position. Furthermore, since the photographing window 113 is covered with a bracket or a cover, there is a problem in that warm air from a heater or a defroster is difficult to reach. In addition, since it is not easy to exchange air between the space covered by the bracket or cover and the outside, there is a problem that when the humidity of the air in the space reaches a saturated state, water droplets tend to adhere to the surface of the glass plate. be. Therefore, it is advantageous to provide the anti-fog sheet 7 within the space covered as described above. In this way, by providing the anti-fog sheet 7, it is not necessary to constantly energize the heating wire 6, and the amount of heat generated by the heating wire 6 can be reduced, so that the power consumption of the heating wire 6 can be reduced. I can do it.

(4) Since the heating wire 6 is sandwiched between the laminated glass 10 and the anti-fog sheet 7, heat radiation from the heating wire 6 to the inside of the vehicle can be suppressed, making it easier to transfer heat to the laminated glass 10. be able to. As a result, it is possible to remove fog and melt ice in a short time. In this case, the base film 71 of the antifogging sheet 7 corresponds to the cover member of the present invention. Note that by covering a portion of the heating wire 6 with the anti-fog sheet 7, heat radiation from the portion not covered by the anti-fog sheet 7 to the inside of the vehicle can be increased. Thereby, the heat applied to the laminated glass 10 by the heating wire 6 is adjusted, and the temperature gradient of the laminated glass 10 can be made gentler. As a result, cracking of the laminated glass 10 can be prevented.

(5) Since the anti-fog sheet 7 is provided with an adhesive layer 72, when the heating wire 6 is covered with the anti-fog sheet 7, the adhesive layer 72 prevents the difference in level between the heating wire 6 and the inner glass plate 12, or The difference in level between the heating wire 6 and the mask layer 110 can be absorbed by the adhesive layer 72. That is, the step and the adhesive layer 72 can be brought into close contact with each other without any gaps. As a result, it is possible to prevent air from being trapped due to the difference in level.

<8. 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.

<8-1>
The wiring pattern of the heating wire 6 is not limited to that shown in the above embodiment, and various patterns are possible. For example, the number of main parts 611, 621 of the first and second heating wires 61, 62, the number of connecting parts 612, 622, the orientation of main parts 611, 621, the length of the connecting wire 63, the orientation of the connecting wire 63, The positions of the connection terminals 64 and 65 can be changed as appropriate. Further, the shape of the photographing window 113 may also be other than trapezoidal, and can be changed as appropriate as long as photographing with the photographing device 2 is possible. If the shape of the imaging window changes, the wiring pattern of the heating wire can also be changed as appropriate.

<8-2>
In the embodiment described above, the heating wire 6 is covered with the anti-fog sheet 7, but the anti-fog sheet 7 is not necessarily necessary. That is, it is sufficient that at least a portion of the heating wire 6 is covered by the bracket and the cover.

<8-3>
Instead of the anti-fog sheet 7, the heating wire 6 can also be covered with a cover member. The cover member can be formed of the same material as the base film 72 of the anti-fog sheet 7, for example, and can be attached to the inner glass plate (including the mask layer) 12 with an adhesive layer. By doing so, heat radiation from the heating wire 6 to the inside of the vehicle can be suppressed.

<8-4>
Part or all of the mask layer 110 may be made of a shielding film that can be attached to the laminated glass 10, 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.

In addition, in the laminated glass 10, from the viewpoint of preventing fogging of the light path, the mask layer 110 is not necessarily necessary, and the heating wire 6 or the anti-fog layer is provided in the region through which the light passes (photographing window: information acquisition region). It is sufficient if the sheet 7 is attached.

<8-5>
In the embodiment described above, the photographing device 2 having a camera 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, it can be applied to various devices such as a laser radar, a light sensor, a rain sensor, a light receiving device that receives a signal from outside the vehicle, such as a light beacon. Further, an opening such as the photographing window 113 described above can be appropriately provided in the mask layer 110 depending on the type of light, and a plurality of openings can also be provided. For example, when a stereo camera is provided, two photographing windows are formed in the mask layer 110, and an anti-fog sheet is attached to each photographing window. Note that the information acquisition device may or may not be in contact with the glass. Further, the photographing window 113 does not need to be closed all the way around, and may be partially open.

Examples of the present invention will be described below. However, the present invention is not limited to the following examples.

A laminated glass having an inner glass plate and an outer glass plate having a thickness of 2 mm was prepared, and the heating wire shown in FIG. 5 was formed on the inner glass plate by screen printing. The heating wire was formed of silver with a line width of 0.3 mm at the main part of the heating wire, a line width of 0.8 mm at the connecting part, and a line width of 3.0 mm at the connecting part. Then, a voltage of 13V was applied to the connection terminal. Further, an anti-fog sheet having an adhesive layer, a base film, and an anti-fog layer and having an area of 18,000 mm ² was prepared. The base film was made of PET with a thickness of 100 μm. Example 1 was obtained by covering the heating wire with an anti-fog sheet, and Example 2 was obtained by not covering the heating wire with an anti-fog sheet. Then, a voltage was applied to each heating wire for 30 minutes, and the temperature of the inner glass plate was measured from the inside of the car using a thermography. The results are shown in FIG.

As shown in FIG. 8, the temperature of the inner glass plate was higher in Example 1 than in Example 2. This is because in Example 1, since the heating wire is covered with the anti-fog sheet, it is thought that a large amount of heat is transferred to the glass plate.

10 Laminated glass 11 Outer glass plate 12 Inner glass plate 13 Intermediate film 110 Mask layer 113 Photographing window (opening)
6 Heating wire 7 Anti-fog sheet 71 Adhesive layer 72 Base film 73 Anti-fog layer

Claims (28)

An information acquisition device that acquires information from outside the vehicle by emitting and/or receiving light is a windshield that can be attached via a bracket,
an outer glass plate,
an inner glass plate disposed opposite to the outer glass plate;
an interlayer film disposed between the outer glass plate and the inner glass plate;
a heating element provided on the vehicle-inward surface of the inner glass plate;
a cover member provided on the vehicle-inward side surface of the inner glass plate and covering at least a portion of the heating element;
Equipped with
The thermal conductivity of the cover member is lower than the thermal conductivity of both the glass plates,
A windshield, wherein at least a portion of the heating element is disposed on a vehicle-inward side surface of the inner glass plate at a position covered by the bracket. The windshield according to claim 1, further comprising an anti-fog means provided on the heating element. The windshield according to claim 1 or 2 , wherein the cover member is provided between the heating element and the anti-fog means. further comprising a shielding layer having an opening through which the light passes, and disposed on at least the vehicle-inward surface of the inner glass plate among the vehicle-inward surface of the inner glass plate and the vehicle-inward surface of the outer glass plate. Prepare,
The windshield according to any one of claims 1 to 3 , wherein the cover member is arranged inside the opening. further comprising a shielding layer having an opening through which the light passes, and disposed on at least the vehicle-inward surface of the inner glass plate among the vehicle-inward surface of the inner glass plate and the vehicle-inward surface of the outer glass plate. Prepare,
The windshield according to any one of claims 1 to 3 , wherein at least a portion of the cover member is arranged so as to protrude from a periphery of the opening. further comprising a shielding layer having an opening through which the light passes, and disposed on at least the vehicle-inward surface of the inner glass plate among the vehicle-inward surface of the inner glass plate and the vehicle-inward surface of the outer glass plate. Prepare,
The windshield according to any one of claims 1 to 3 , wherein the heating element has a heating wire, and at least a part of the heating wire is arranged to pass through the opening. The windshield according to claim 6 , wherein the heating element is covered by the cover member. The windshield according to claim 6 , wherein at least a portion of a peripheral edge of the heating element is not covered with the cover member. The windshield according to any one of claims 6 to 8 , wherein at least a part of the heating wire has a line width of 0.5 mm or less at a portion passing through the opening. At least a portion of the heating wires passing through the opening are arranged substantially in parallel,
The windshield according to any one of claims 6 to 8 , wherein in the heating wire, an interval between substantially parallel portions of the opening is 1 mm or more. The heating wire has at least one bent part,
The windshield according to any one of claims 6 to 10 , wherein the bent portion is formed in a curved shape. The windshield according to claim 11 , wherein a line width of the bent portion is thicker than a line width of a portion of the heating wire other than the bent portion. The windshield according to any one of claims 6 to 12 , wherein a line width of at least a portion of the heating wire inside the opening is narrower than an average line width of the heating wire outside the opening. The windshield according to any one of claims 6 to 13 , wherein the heating element is configured by two or more parallel circuits. The windshield according to claim 14 , wherein the opening has an area of 7000 mm ² or more. The windshield according to claim 14 or 15 , wherein the resistance value of each of the parallel circuits is within ±30% of the average of the resistance values of the two or more parallel circuits. A line width of a portion extending outside the opening is adjusted so that the resistance value of each of the parallel circuits is within ±30% of the average resistance value of the two or more parallel circuits. The windshield according to item 14 or 15 . The window according to claim 14 or 15 , wherein in the heating wire in each of the parallel circuits, a wire length ratio of a portion disposed inside the opening is within 30% of the entire length of the heating wire. shield. the heating element has a heating wire,
The windshield according to any one of claims 1 to 18 , wherein the heating wire is printed on the vehicle-inward side surface of the inner glass plate. Further comprising an anti-fog means provided on the heating element,
20. The windshield according to claim 2, wherein the anti-fog means includes an anti-fog film made of a water-absorbing resin.
The windshield according to claim 20 , further comprising a base film on which the anti-fog film is disposed, and an adhesive layer provided on a surface of the base film opposite to the anti-fog film. . The windshield according to claim 21 , wherein the base film constitutes the cover member. The windshield according to any one of claims 1 to 20 , wherein the cover member has an adhesive layer. The windshield according to claim 23 , wherein the thickness of the adhesive layer is greater than the thickness of the heating element and 20 times or less the thickness. further comprising a shielding layer having an opening through which the light passes, and disposed on at least the vehicle-inward surface of the inner glass plate among the vehicle-inward surface of the inner glass plate and the vehicle-inward surface of the outer glass plate. Prepare,
The windshield according to claim 23 or 24 , wherein the thickness of the adhesive layer is greater than the thickness of the shielding layer and 20 times or less the thickness. The windshield according to any one of claims 23 to 25 , wherein the adhesive layer has a shear storage modulus at 20° C. of 1.0×10 ³ GPa or more and 1.0×10 ⁷ GPa or less. The windshield according to any one of claims 23 to 26 , wherein the adhesive force of the adhesive layer is 0.25 N/10 mm or more and 12 N/mm or less. The windshield according to any one of claims 23 to 27 , wherein the cover member has a thickness of 25 μm or more and 200 μm or less.