Patent Description:
In some cases, in order to improve anti-glare and heat shielding properties, a band-shaped shade region colored green, blue, or the like is formed in a laminated glass for a vehicle, and in particular, a windshield, in which an interlayer film is arranged between a pair of glass plates. The shade region is provided on the surface of the glass plate in some cases, but is often formed by coloring part of the interlayer film in a band shape. On the other hand, since a windshield has a statutory field-of-view region in which the visible light transmittance should be a predetermined value or more (e.g., <NUM>% or more), the shade region of the windshield is arranged outside of the field-of-view region, that is, normally at an upper portion of the windshield.

Incidentally, in recent years, the safety performance of automobiles has been improving dramatically, and as one of these improvements, a safety system has been proposed in which a distance to a vehicle in front and a speed of the vehicle in front are detected and a brake is automatically operated when an abnormal approach occurs, in order to avoid a collision with the vehicle in front. In such a system, a device such as a laser radar, a camera, or the like is used to measure the distance to the vehicle in front and the like using a laser, infrared rays, or the like. Also, in general, it is desired that these devices are attached to the upper portion of the windshield in order to ensure safety and sufficiently exhibit the functions of the devices.

However, since the shade region is formed at the upper portion of the windshield as described above, it is necessary to form an opening through which the light of a camera or the like can pass in the shade region, in order to attach a device such as a laser radar. In view of this, for example, <CIT> discloses the following method.

That is, in <CIT>, a through hole is formed in the shade region, and a transparent sheet member is fitted into the through hole, whereby the camera can capture an image of the outside of the vehicle through the sheet member.

<CIT> concerns a windshield in which it is possible to install an information obtaining device that obtains information from outside the vehicle by radiating light and/or receiving light.

Incidentally, since the sheet member and the shade region are different members, it is very difficult to make them exactly the same thickness, and if there is a difference in thickness, there is a risk that a level difference will occur at the boundary between the sheet member and the shade area. In this case, the inventor of the present invention has found that in some cases, the glass plates sandwiching the interlayer film bend along the sheet member instead of coming into contact with the interlayer film so as to flatten the level difference. For this reason, the inventor of the present invention found that a gap may be formed between the glass plate and the interlayer film at the location where the above-mentioned level difference occurs, and as a result, air may accumulate at the level difference at the time of manufacturing the laminated glass. For this reason, from the vehicle interior side or the vehicle exterior side of the laminated glass, the air accumulated at the level difference looks like a bubble, and there is a risk that the appearance will deteriorate. This point is not limited to a windshield, but is a problem that can occur in other laminated glasses as well.

The present invention has been made to solve the above-described problem, and aims to provide a laminated glass according to which deterioration of the appearance due to the occurrence of bubbles or the like can be suppressed even if the thicknesses of the sheet member and the shade region (or a later-described non-shade region) are different in the interlayer film.

The present invention relates to a laminated glass as defined in claim <NUM>.

According to the present invention, it is possible to suppress deterioration of appearance caused by the occurrence of a bubble even if thicknesses of the sheet member and the shade region (or a later-described non-shade region) are different in the interlayer film.

Hereinafter, an embodiment in which the laminated glass according to the present invention is applied to a windshield will be described. First, a configuration of the windshield according to the present embodiment will be described with reference to <FIG> and <FIG>. <FIG> is a plan view of the windshield, and <FIG> is a cross-sectional view of <FIG>. Note that for the sake of convenience of description, the up-down direction in <FIG> is referred to as "up-down" and "vertical", and the left-right direction in <FIG> is referred to as "left-right". <FIG> illustrates a windshield viewed from a vehicle interior side. That is, the far side from the sheet surface in <FIG> is the vehicle exterior side, and the near side from the sheet surface in <FIG> is the vehicle interior side.

This windshield includes a trapezoidal laminated glass <NUM> and is installed in a vehicle body in an inclined state. The laminated glass <NUM> has an outer glass plate <NUM>, an inner glass plate <NUM>, and an interlayer film <NUM> arranged between them. A mask layer <NUM> is laminated on the surface on the vehicle interior side of the outer glass plate <NUM> and the surface on the vehicle interior side of the inner glass plate <NUM>, and the mask layer <NUM> blocks the field of view from the outside of the vehicle. Also, an opening <NUM> is formed in the mask layer <NUM>, and an image capture device <NUM> arranged inside the vehicle can capture an image of the state outside the vehicle through the opening <NUM>. That is, the opening <NUM> constitutes an image capture window. Furthermore, a frame-shaped bracket <NUM> is fixed on the mask layer <NUM> of the inner glass plate <NUM>, and the image capture device <NUM> is attached to the bracket <NUM>. Since the bracket <NUM> is formed in a frame shape and fixed on the mask layer <NUM>, the bracket <NUM> cannot be seen from the outside of the vehicle. Hereinafter, each constituent element will be described in detail.

<FIG> is a cross-sectional view of the laminated glass. As shown in the drawing, the laminated glass <NUM> includes the outer glass plate <NUM> and the inner glass plate <NUM>, and the resin interlayer film <NUM> is arranged between the glass plates <NUM> and <NUM>. Hereinafter, these configurations will be described.

First, the outer glass plate <NUM> and the inner glass plate <NUM> will be described. As the outer glass plate <NUM> and the inner glass plate <NUM>, known glass plates can be used, and the outer glass plate <NUM> and the inner glass plate <NUM> can be made of heat ray absorbing glass, general clear glass or green glass, or UV green glass. However, these glass plates <NUM> and <NUM> need to realize visible light transmittance in accordance with a safety standard of the country in which the automobile is to be used. For example, the outer glass plate <NUM> can ensure a required solar absorptivity, and the inner glass plate <NUM> can adjust the visible light transmittance so as to satisfy a safety standard. Examples of clear glass, heat ray absorbing glass, and soda lime-based glass are shown below.

The composition of the heat ray absorbing glass can be, for example, using the composition of clear glass as a reference, a composition in which the percentage of total iron oxide (T-Fe<NUM>O<NUM>) converted to Fe<NUM>O<NUM> is <NUM> to <NUM> mass%, the percentage of CeO<NUM> is <NUM> to <NUM> mass%, the percentage of TiO<NUM> is <NUM> to <NUM> mass%, and the skeleton components of glass (mainly SiO<NUM> and Al<NUM>O<NUM>) have been reduced by the amount by which T-Fe<NUM>O<NUM>, CeO<NUM>, and TiO<NUM> increase.

Although the thickness of the laminated glass <NUM> according to the present embodiment is not particularly limited, the total thickness of the outer glass plate <NUM> and the inner glass plate <NUM> can be set to, for example, <NUM> to <NUM>, and from the viewpoint of weight reduction, the total thickness of the outer glass plate <NUM> and the inner glass plate <NUM> is preferably <NUM> to <NUM>, more preferably <NUM> to <NUM>, and particularly preferably <NUM> to <NUM>. As described above, in order to reduce the weight, it is necessary to reduce the total thickness of the outer glass plate <NUM> and the inner glass plate <NUM>, and therefore, although the thickness of each glass plate is not particularly limited, for example, the thicknesses of the outer glass plate <NUM> and the inner glass plate <NUM> can be determined as follows.

The outer glass plate <NUM> is mainly required to have durability and impact resistance against external obstacles, and as a windshield of an automobile, it is required to have impact resistance against flying objects such as pebbles. On the other hand, the greater the thickness is, the heavier the weight is, which is not preferable. From this viewpoint, the thickness of the outer glass plate <NUM> is preferably <NUM> to <NUM>, and more preferably <NUM> to <NUM>. The thickness to be used can be determined according to the application of the glass.

The thickness of the inner glass plate <NUM> can be made equal to that of the outer glass plate <NUM>, but for example, the thickness can be made smaller than that of the outer glass plate <NUM> in order to reduce the weight of the laminated glass <NUM>. Specifically, considering the strength of the glass, the thickness is preferably <NUM> to <NUM>, preferably <NUM> to <NUM>, and particularly preferably <NUM> to <NUM>. Also, the thickness is preferably <NUM> to <NUM>. As for the inner glass plate <NUM>, the thickness to be used can be determined according to the application of the glass.

Here, an example of a method for measuring the thickness when the glass plate (laminated glass) <NUM> is curved will be described. First, the measurement positions are two points above and below a center line S extending in the vertical direction along the center of the glass plate in the left-right direction. Although there is no particular limitation on the measurement device, for example, a thickness gauge such as SM-<NUM> manufactured by Teclock Corporation 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 by the thickness gauge and measurement is performed. Note that even if the glass plate is flat, measurement can be performed in the same manner as if the glass plate is curved.

<FIG> is a plan view of the interlayer film. As shown in <FIG>, the interlayer film <NUM> is formed to have the same size as the glass plates <NUM> and <NUM>, and includes a band-shaped shade region <NUM> forming the upper end portion of the interlayer film <NUM>, a non-shade region <NUM> that is connected to the lower end portion of the shade region <NUM> and occupies most of the interlayer film <NUM>, and a sheet member <NUM> that is arranged between the shade region <NUM> and the non-shade region <NUM>.

The shade region <NUM> is a region having a high transmittance loss for visible light, and is colored, for example, black, green, blue, or the like. The shade region <NUM> performs various functions (anti-glare, heat-shielding, etc.) that accompany dimming. On the other hand, the non-shade region <NUM> is an uncolored and transparent region.

The interlayer film <NUM> is made of at least one layer in both the shade region <NUM> and the non-shade region <NUM>, and as an example of the non-shade region <NUM>, as shown in the enlarged diagram of <FIG>, a soft core layer <NUM> can be made of three layers sandwiched between outer layers <NUM>, which are harder than the soft core layer <NUM>. However, the present invention is not limited to this configuration, and may be made of a plurality of layers including the core layer <NUM> and at least one outer layer <NUM> arranged on the outer glass plate <NUM> side. For example, a two-layer interlayer film <NUM> including the core layer <NUM> and one outer layer <NUM> arranged on the outer glass plate <NUM> side, or an interlayer film <NUM> in which an even number of two or more outer layers <NUM> are respectively arranged on both sides centered about the core layer <NUM>, or an interlayer film <NUM> in which an odd number of outer layers <NUM> are arranged on one side of the core layer <NUM> and an even number of outer layers <NUM> are arranged on the other side of the core layer <NUM>. Note that if only one outer layer <NUM> is provided, the outer layer <NUM> is provided on the outer glass plate <NUM> side as described above, but this is for improving the damage resistance performance against an external force from outside of the vehicle or outdoors. Additionally, if there are a large number of outer layers <NUM>, the sound insulation performance is also higher.

As long as the core layer <NUM> is softer than the outer layer <NUM>, there is no particular limitation on the hardness of the core layer <NUM>. There is no particular limitation on the material constituting the layers <NUM> and <NUM>, but for example, the material can be selected based on the Young's modulus. Specifically, the Young's modulus of the core layer <NUM> is preferably <NUM> to <NUM> MPa, more preferably <NUM> to <NUM> MPa, and particularly preferably <NUM> to <NUM> MPa at a frequency of <NUM> and a temperature of <NUM>. Within such a range, it is possible to prevent the sound transmission loss (STL) from decreasing in a low frequency range of about <NUM> or less. On the other hand, the Young's modulus of the outer layer <NUM> is preferably large in order to improve the sound insulation performance in the high frequency range, as will be described later, and can be <NUM> MPa or more, <NUM> MPa or more, <NUM> MPa or more, <NUM> MPa or more, <NUM> MPa or more, <NUM> MPa or more, or <NUM> MPa or more, at a frequency of <NUM> and a temperature of <NUM> degrees. Although there is no particular limitation on the upper limit of the Young's modulus of the outer layer <NUM>, the upper limit can be set from the viewpoint of workability, for example. For example, it is empirically known that when the upper limit is <NUM> MPa or more, workability, and in particular, cutting, becomes difficult.

Also, as a specific material, the outer layer <NUM> can be made of, for example, polyvinyl butyral resin (PVB). Polyvinyl butyral resin is preferable because it has excellent adhesiveness with each glass plate and penetration resistance. On the other hand, the core layer <NUM> can be made of, for example, ethylene vinyl acetate resin (EVA) or a polyvinyl acetal resin softer than the polyvinyl butyral resin constituting the outer layer. By sandwiching the soft core layer therebetween, the sound insulation performance can be greatly improved while maintaining the same adhesiveness and penetration resistance as the single-layer resin interlayer film.

Generally, the hardness of a polyvinyl acetal resin can be controlled by (a) the degree of polymerization of polyvinyl alcohol, which is a starting material, (b) the degree of acetalization, (c) the type of plasticizer, (d) the addition ratio of the plasticizer, and the like. Accordingly, by appropriately adjusting at least one selected from these conditions, even if the same polyvinyl butyral resin is used, it is possible to create both the hard polyvinyl butyral resin used for the outer layer <NUM> and the soft polyvinyl butyral resin used for the core layer <NUM>. Furthermore, the hardness of the polyvinyl acetal resin can also be controlled by the type of aldehyde used for acetalization, co-acetalization with a plurality of types of aldehydes, or pure acetalization with a single type of aldehyde. Although it cannot be said unconditionally, polyvinyl acetal resin obtained by using an aldehyde having a large number of carbon atoms tends to be softer. Accordingly, for example, if the outer layer <NUM> is constituted by polyvinyl butyral resin, a polyvinyl acetal resin obtained by acetalizing an aldehyde having <NUM> or more carbon atoms (e.g., n-hexyl aldehyde, <NUM>-ethylbutyl aldehyde, n-heptyl aldehyde, n-octyl aldehyde) with polyvinyl alcohol can be used in the core layer <NUM>. Note that if a predetermined Young's modulus can be obtained, there is no limitation to the above resins and the like.

The shade region <NUM> can also be constituted by the same layer configuration as the non-shade region <NUM>, for example, a core layer and a pair of outer layers sandwiching the core layer. As described above, the shade region <NUM> is colored, but for example, any one or more of the core layer and the outer layers can be colored with a colorant such as a pigment or a dye. As the pigment, for example, an organic pigment that is azo-based, phthalocyanine-based, quinacridone-based, or the like, and inorganic pigments such as metal oxides and metal powders can be used.

If a pigment is used, the colored core layer and the uncolored transparent outer layers can be respectively produced using an extrusion molding method from a resin composition obtained by kneading the pigment together with a resin and a plasticizer and a resin composition containing no pigment (resin and plasticizer), and the colored shade region <NUM> can be obtained by performing molding by sandwiching the core layer between the outer layers. On the other hand, if a dye is used, a mask is used to expose a region of the interlayer film <NUM> on which the shade region <NUM> is to be formed, and the dye is applied to this region. The dye can be applied, for example, by spraying or printing.

Next, the sheet member <NUM> will be described. As shown in <FIG>, a rectangular through hole <NUM> is formed in the center of the interlayer film <NUM> in the left-right direction so as to straddle the boundary between the shade region <NUM> and the non-shade region, and the above-described sheet member <NUM> is arranged on this through hole <NUM>. That is, by combining a rectangular recessed portion formed at the lower end of the shade region <NUM> and the rectangular recessed portion formed near the center of the upper end portion of the non-shade region <NUM>, the above-mentioned rectangular through hole <NUM> is formed. The sheet member <NUM> is made of a transparent material, can be constituted by one layer, or can be constituted by a plurality of layers similarly to the shade region <NUM> or the non-shade region <NUM>. Also, if it is constituted by one layer, it can also be made of any material of the core layer or the outer layer described above.

The sheet member <NUM> is arranged at a position corresponding to the extending portion <NUM> of the mask layer <NUM>, which will be described later, and the opening <NUM> formed in the extending portion <NUM> is located inside the sheet member <NUM>. Accordingly, the seat member <NUM> is arranged inside the opening <NUM>.

The total thickness of the interlayer film <NUM> is not particularly specified, but is preferably <NUM> to <NUM>, more preferably <NUM> to <NUM>, and particularly preferably <NUM> to <NUM>. The thickness of the core layer <NUM> is preferably <NUM> to <NUM>, and more preferably <NUM> to <NUM>. On the other hand, the thickness of each outer layer <NUM> is preferably <NUM> to <NUM>, and more preferably <NUM> to <NUM>. In addition, the thickness of the core layer <NUM> can be adjusted within these conditions with the total thickness of the interlayer film <NUM> kept constant.

The thickness of the core layer <NUM> and the outer layer <NUM> can be measured, for example, as follows. First, the cross section of the laminated glass is magnified <NUM> times and displayed by a microscope (e.g., VH-<NUM> manufactured by KEYENCE). Also, the thicknesses of the core layer <NUM> and the outer layer <NUM> are visually specified and measured. At this time, in order to eliminate variation due to eyesight, the number of instances of measurement is set to five, and the average value thereof is taken as the thickness of the core layer <NUM> and the outer layer <NUM>. For example, an enlarged photograph of the cross section of the laminated glass is taken, and the core layer <NUM> and the outer layer <NUM> are specified therein and the thickness is measured.

Note that the thicknesses of the core layer <NUM> and the outer layer <NUM> of the interlayer film <NUM> do not need to be constant over the entire surface, and for example, can also be wedge-shaped for use in laminated glass to be used in a head-up display. In this case, the thickness of the core layer <NUM> and the outer layer <NUM> of the interlayer film <NUM> is measured at the thinnest portion, that is, the lowest edge portion of the laminated glass. If the interlayer film <NUM> has a wedge shape, the outer glass plate <NUM> and the inner glass plate <NUM> are not arranged in parallel, but such an arrangement is also assumed to be encompassed in the glass plate of the present invention. That is, the present invention includes, for example, the arrangement of the outer glass plate and the inner glass plate when the interlayer film <NUM> using the core layer <NUM> and the outer layers <NUM> whose thickness increases at a rate of change of <NUM> or less per meter is used.

Although there is no particular limitation on the method for producing the interlayer film <NUM>, examples thereof include a method of blending a resin component such as the above-mentioned polyvinyl acetal resin, a plasticizer, and other additives as necessary, kneading them uniformly, and thereafter collectively performing extrusion molding on each layer, and a method of laminating two or more resin films produced by this method, through pressing, laminating, or the like. The unlaminated resin film used in the method of laminating through pressing, laminating, or the like may have a single-layer structure or a multi-layer structure. Also, the interlayer film <NUM> can be made of one layer instead of being made of a plurality of layers as described above. Then, after the through hole <NUM> as described above is formed, the sheet member <NUM> can be fitted therein.

Next, the mask layer <NUM> will be described. As shown in <FIG> and <FIG>, the mask layer <NUM> is formed on both the surface on the vehicle interior side of the inner glass plate <NUM> and the inner surface of the outer glass plate <NUM>. Since the mask layers <NUM> formed on the inner glass plate <NUM> and the outer glass plate <NUM> have the same shape and are laminated at the same position, the mask layer <NUM> laminated on the inner glass plate <NUM> will be described below.

The mask layer <NUM> includes a peripheral edge portion <NUM> laminated along the entirety of the peripheral edge of the inner glass plate <NUM>, and a rectangular extended portion <NUM> that is connected to the peripheral edge portion <NUM> and extends downward from the vicinity of the center of the upper side of the inner glass plate <NUM>. A trapezoidal opening <NUM> is formed at the lower end of the extended portion <NUM>, and the image capture device <NUM> attached to the vehicle interior side can capture an image of the outside of the vehicle through the opening <NUM> and the laminated glass <NUM>. Also, a boundary <NUM> between the shade region <NUM> and the non-shade region <NUM> of the interlayer film <NUM> described above extends in the horizontal direction so as to pass through the opening <NUM>.

As shown in <FIG>, the bracket <NUM> described above is fixed on the mask layer <NUM>. Specifically, the bracket <NUM> is formed in a frame shape so as to surround the opening, and is fixed to the mask layer <NUM> with double-sided tape, an adhesive, or the like. Then, the image capture device <NUM> is supported by the bracket <NUM>, and is configured to capture an image of the outside of the vehicle through the opening <NUM>. Also, although not shown in the drawing, a cover is attached to the bracket <NUM> so that the image capture device <NUM> cannot be seen from the inside of the vehicle.

Next, the material of the mask layer <NUM> will be described. The material of the mask layer <NUM> may be selected as appropriate depending on the embodiment as long as it can shield the field of view from the outside of the vehicle, and for example, a ceramic in a dark color such as black, brown, gray, or navy blue may be used.

If black ceramic is selected as the material of the mask layer <NUM>, for example, black ceramic is laminated on the inner surface of the inner glass plate <NUM> by screen printing or the like, and the laminated ceramic is heated together with the glass plates <NUM> and <NUM>. When the ceramic is cured, the mask layer <NUM> is completed. Note that as the ceramic used for each mask layer <NUM>, various materials can be used. For example, a ceramic having the compositions shown in Table <NUM> below can be used for the mask layer <NUM>.

Next, an in-vehicle system including an image capture device <NUM> and an image processing device <NUM> will be described with reference to <FIG> and <FIG> illustrates the configuration of the in-vehicle system. As illustrated in <FIG>, the in-vehicle system according to the present embodiment includes the above-described image capture device <NUM> and the image processing device <NUM> connected to the image capture device <NUM>.

The image processing device <NUM> is a device that processes the captured image acquired by the image capture device <NUM>. The image processing device <NUM> has, for example, general hardware such as a storage unit <NUM>, a control unit <NUM>, and an input/output unit <NUM>, which are connected by a bus, as a hardware configuration. However, the hardware configuration of the image processing device <NUM> does not need to be limited to such an example, and with respect to the specific hardware configuration of the image processing device <NUM>, constituent elements can be added or omitted as appropriate according to the embodiment.

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

As described above, the laminated glass <NUM> is arranged in an inclined posture with respect to the vertical direction and is curved. Then, the image capture device <NUM> captures an image of the state outside of the vehicle through such a laminated glass <NUM>. For this reason, the captured image acquired by the image capture device <NUM> is deformed according to the posture, shape, refractive index, optical defect, and the like of the laminated glass <NUM>. An aberration unique to the camera lens of the image capture device <NUM> is also added. In view of this, the storage unit <NUM> may store correction data for correcting an image deformed by the laminated glass <NUM> and the aberration of the camera lens.

The control unit <NUM> 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), interface circuits, etc.) used for processing of this processor. The ROM, RAM, and the like may also be referred to as a main storage device in the sense that they are arranged in the address space handled by the processor in the control unit <NUM>. The control unit <NUM> functions as an image processing unit <NUM> by executing various data and programs stored in the storage unit <NUM>.

The image processing unit <NUM> processes the captured image acquired by the image capture device <NUM>. The processing of the captured image can be selected as appropriate according to the embodiment. For example, the image processing unit <NUM> may recognize the subject appearing in the captured image by analyzing the captured image through pattern matching or the like. In the present embodiment, since the image capture device <NUM> captures an image of the state in front of the vehicle, the image processing unit <NUM> may further determine whether or not an organism such as a human being has appeared in front of the vehicle based on subject recognition. Then, if a person appears in front of the vehicle, the image processing unit <NUM> may output a warning message using a predetermined method. Also, for example, the image processing unit <NUM> may carry out predetermined processing on the captured image. Then, the image processing unit <NUM> may output the processed captured image to a display device (not shown) such as a display connected to the image processing device <NUM>.

The input/output unit <NUM> is one or a plurality of interfaces for transmitting/receiving data to/from a device that is outside of the image processing device <NUM>. The input/output unit <NUM> is, for example, an interface for connecting to a user interface or an interface such as USB (Universal Serial Bus). Note that in the present embodiment, the image processing device <NUM> is connected to the image capture device <NUM> via the input/output unit <NUM>, and acquires a captured image captured by the image capture device <NUM>.

As such an image processing device <NUM>, a general-purpose device such as a PC (Personal Computer) or a tablet terminal may be used in addition to a device designed exclusively for the service to be provided.

Also, the image capture device <NUM> is attached to the bracket <NUM> as described above. Accordingly, in this state, the attachment of the image capture device <NUM> to the bracket <NUM> and the attachment of the bracket to the mask layer <NUM> are adjusted such that the optical axis of the camera lens of the image capture device <NUM> passes through the opening <NUM>. Also, a cover (not shown) is attached to the bracket <NUM> so as to cover the image capture device <NUM>. Accordingly, the image capture device <NUM> is arranged in the space surrounded by the laminated glass <NUM>, the bracket <NUM>, and the cover so that it cannot be seen from the vehicle interior side, and so that only a portion of the image capture device <NUM> can be seen through the opening <NUM> by the mask layer <NUM> from the vehicle exterior side as well. Also, the image capture device <NUM> and the above-mentioned input/output unit <NUM> are connected by a cable (not shown), and this cable is pulled out from the cover and connected to the image processing device <NUM> arranged at a predetermined position in the vehicle.

Next, a method for manufacturing the windshield will be described. First, the mask layer <NUM> is laminated on the outer glass plate <NUM> and the inner glass plate <NUM> formed in a predetermined shape. Next, these glass plates <NUM> and <NUM> are formed so as to be curved. This method is not particularly limited, but can be performed through, for example, known press-forming. Alternatively, after the outer glass plate <NUM> and the inner glass plate <NUM> are placed on top of each other on the molding die, the molding die is passed through a heating furnace to be heated. As a result, these glass plates <NUM> and <NUM> can be curved by their own weight.

When the outer glass plate <NUM> and the inner glass plate <NUM> are formed in this manner, a laminate in which the interlayer film <NUM> is sandwiched between the outer glass plate <NUM> and the inner glass plate <NUM> is subsequently formed. Note that the interlayer film <NUM> has a shape larger than that of the glass plates <NUM> and <NUM>.

Next, this laminate is placed in a rubber bag and pre-adhered at about <NUM> to <NUM> while being suctioned under reduced pressure. The method of pre-adhesion can be other than this, and the following method can also be adopted. For example, the above-described laminate is heated in an oven at <NUM> to <NUM>. Next, the laminate is pressed by a roll at <NUM> to <NUM> MPa. Subsequently, the laminate is heated again in the oven at <NUM> to <NUM>, and then pressed again with a roll at <NUM> to <NUM> MPa. In this manner, the pre-adhesion is completed.

Next, the main adhesion is performed. The pre-adhered laminate is subjected to main adhesion by an autoclave, for example, at <NUM> to <NUM> atm and at <NUM> to <NUM>. Specifically, for example, the main adhesion can be performed at <NUM> atm under the condition of <NUM>. Through the above-described pre-adhesion and main adhesion, the interlayer film <NUM> is adhered to the glass plates <NUM> and <NUM>. Subsequently, the interlayer film <NUM> protruding from the outer glass plate <NUM> and the inner glass plate <NUM> is cut.

Although the sheet member <NUM> basically has the same thickness as the shade region <NUM> and the non-shade region <NUM>, it has been found by the inventor of the present invention that, for example, if the thickness of the sheet member <NUM> is different from the thickness of the shade region <NUM> and the non-shade region <NUM>, this affects the thickness of the laminated glass <NUM>. This point will be described with reference to <FIG>. <FIG> is a cross-sectional view taken along line X-X of <FIG> is a partial plan view of the laminated glass, <FIG> is a cross-sectional view taken along line Y-Y of <FIG> is a partial plan view of the laminated glass, and <FIG> is a partial plan view of the laminated glass.

For example, as shown in <FIG>, it has been found that if the thickness of the sheet member <NUM> is larger than the thickness of the shade region <NUM> and the non-shade region <NUM>, that is, if a level difference occurs due to the difference in thickness, the sheet member <NUM> forms a protruding portion on the surface of the interlayer film <NUM>, the outer glass plate <NUM> does not come into contact with the interlayer film <NUM> so as to flatten the protruding portion, the outer glass plate <NUM> curves along the protruding portion, and the thickness becomes greater than that of the other portions. Note that although the example of <FIG> shows an example in which the sheet member <NUM> protrudes to the outer glass plate <NUM> side, it is also conceivable that the sheet member <NUM> protrudes toward the inner glass plate <NUM> or protrudes toward both glass plates <NUM> and <NUM>.

In this case, since a level difference occurs at the boundary between the sheet member <NUM> and the shade region <NUM>, there is a possibility that a gap R in which air accumulates will be formed between the outer glass plate <NUM> and the interlayer film <NUM> when the laminated glass <NUM> is manufactured. In this manner, when air enters the level difference, there is a risk that the appearance will deteriorate, and therefore, in the present embodiment, the following is specified.

First, as shown in <FIG>, the inventor of the present invention has found that when the thickness of the windshield at the center point M of the sheet member <NUM> is defined as H1, and the thickness of the windshield at the point N that is <NUM> from the edge portion of the sheet member <NUM> on the virtual line L extending in the horizontal direction through the center point M is defined as H2, if H1 is larger than H2 (Equation (<NUM>)), there is a possibility that the sheet member will form a protruding portion on the surface of the interlayer film <NUM> as shown in <FIG>.

That is, since the difference in thickness between the sheet member <NUM> and the shade region <NUM> (or the non-shade region <NUM>) cannot be measured directly from the windshield after manufacture, by measuring H1 and H2 as described above, the inventor of the present invention has found that there is a possibility that there is a difference in thickness between the sheet member <NUM> and the shade region <NUM>, and a protruding portion such as that described above will occur. The same applies also when a recessed portion is formed by the sheet member <NUM>, as will be described later.

In this case, as shown in <FIG> and <FIG>, when any point A on the inner edge of the opening <NUM>, a point B having the shortest distance from the point A on the outer edge of the sheet member <NUM>, and a point C where a virtual line K extending from the point A through the point B and the outer edge of the extended portion <NUM> of the mask layer <NUM> intersect each other are defined, the distance between the points A and B is defined as S1, and the distance between the points B and C is defined as S2, the following equation (<NUM>) is satisfied at the location where S1+S2 is the minimum. Note that although the location where S1+S2 is minimized depends on the shape of the mask layer <NUM> and the shape of the sheet member <NUM>, in the present embodiment, it is a location between the corner portion (point A) at the lower end of the opening <NUM> and the edge portion (point C) of the extended portion <NUM> of the mask layer <NUM>.

As a result, in the extended portion <NUM>, the region outside the outer edge of the sheet member <NUM> (the region between the point B and the point C) becomes large, and therefore the gap R is easily hidden by the mask layer <NUM>, and it is possible to suppress a case in which this is visible from the vehicle exterior and the vehicle interior. Note that in order to satisfy equation (<NUM>), for example, the size of the sheet member <NUM> may be adjusted, or the width of the extended portion <NUM> (the length from the inner edge of the opening <NUM> to the outer edge of the extended portion <NUM>) may be adjusted.

Note that as a result of study performed by the inventor of the present invention, bubbles of various widths (direction orthogonal to the outer edge of the sheet member <NUM>) have been confirmed as the bubbles accumulated in the gap R depending on the conditions, but in order to hide them, S2 is preferably <NUM> or more, more preferably <NUM> or more, and even more preferably <NUM> or more. However, if S2 is too large, the mask layer <NUM> becomes large and the field of view of the windshield becomes narrow. Accordingly, S2 is preferably <NUM> or less, and more preferably <NUM> or less. From this point of view, S1+S2 is preferably <NUM> to <NUM>.

Also, the inventor of the present invention found that the gap R is likely to occur particularly when the following equation (<NUM>) is satisfied. Accordingly, when the following equation (<NUM>) is satisfied, it is possible to suppress a case in which the gap R is visible from the vehicle exterior, especially when equation (<NUM>) is satisfied.

Here, the inventor of the present invention performed a study using a laminated glass having an outer glass plate with a thickness of <NUM>, an inner glass plate with a thickness of <NUM>, and an interlayer film with a thickness of <NUM> (thickness other than the sheet member <NUM>), and the results are as follows.

In Table <NUM>, when H1-H2 is negative, it is thought that the thickness of the sheet member <NUM> is less than that of the shade region <NUM> (or the non-shade region <NUM>) as shown in later-described <FIG>. When H1-H2 is <NUM>, it is thought that there is no level difference between the sheet member <NUM> and the shade region <NUM> (or the non-shade region <NUM>). Accordingly, no bubbles are confirmed. Similarly, no bubbles are confirmed also when H1-H2 is <NUM> and -<NUM>. That is, it is thought that the larger the absolute value of H1-H2 is, the larger the level difference is, and as a result the width of the gap R becomes larger. Also, when the width of the gap R is large, many bubbles can be seen. In particular, it has been confirmed that the bubbles become larger when the above equation (<NUM>) is satisfied.

Although a case where the protruding portion is formed on the interlayer film <NUM> by the sheet member <NUM> has been described above, a case where a recessed portion is formed in the interlayer film <NUM> by the sheet member <NUM> will be described next.

For example, as shown in <FIG>, it was found that if the thickness of the sheet member <NUM> is smaller than the thickness of the shade region <NUM> and the non-shade region <NUM>, the sheet member <NUM> forms a recessed portion in the surface of the interlayer film <NUM>, but the outer glass plate <NUM> does not come into contact with the interlayer film <NUM> so as to absorb the recessed portion, but the outer glass plate <NUM> is curved along the recessed portion and the thickness is less than that of the other portions. Note that although the example of <FIG> shows an example in which the sheet member <NUM> is recessed toward the outer glass plate <NUM>, it is also conceivable that the sheet member <NUM> is recessed toward the inner glass plate <NUM> or is recessed toward both glass plates <NUM> and <NUM>.

First, as described above, when the thicknesses H1 and H2 are defined, the inventor of the present invention found that if H1 is smaller than H2 (equation (<NUM>)), there is a possibility that the sheet member <NUM> will form a recessed portion in the surface of the interlayer film <NUM> as shown in <FIG>.

In this case, as shown in <FIG> and <FIG>, the above-mentioned point A, point B, point C, distance S1, and distance S2 are defined, and the following equation (<NUM>) is satisfied at the location where S1+S2 is minimized.

As a result, in the extended portion <NUM>, the region where the gap R occurs (the region between the points A and B) becomes large, and therefore the gap R can be hidden by the mask layer <NUM> and a case in which the gap R is visible from the vehicle exterior and the vehicle interior can be suppressed. Note that in order to satisfy equation (<NUM>), for example, the size of the sheet member <NUM> may be adjusted, or the width of the extended portion <NUM> (the length from the inner edge of the opening <NUM> to the outer edge of the extended portion <NUM>) may be adjusted.

As a result of the study by the inventor of the present invention, it was confirmed that the bubbles accumulated in the gap R have various widths (direction orthogonal to the outer edge of the sheet member <NUM>) since they depend on the condition, but in order to hide them, S1 is preferably <NUM> or more, more preferably <NUM> or more, and even more preferably <NUM> or more. However, if S1 is too large, the opening <NUM> becomes small. Accordingly, S2 is preferably <NUM> or less, and more preferably <NUM> or less. From this viewpoint, S1+S2 is preferably <NUM> to <NUM>.

Also, the inventor of the present invention found that the gap R is likely to occur particularly when the following equation (<NUM>) is satisfied. Accordingly, if the following equation (<NUM>) is satisfied, it is possible to suppress a case in which the gap R is visible from the vehicle exterior, especially when equation (<NUM>) is satisfied.

Note that in the above example, any point A at the edge portion of the opening <NUM> was examined, but in particular, it is preferable that the above equations (<NUM>) and (<NUM>) are satisfied in <NUM>% or more of both lateral sides and the lower side of the opening <NUM>, and it is more preferable that these equations are satisfied in the entire periphery.

According to the windshield described above, the following effects can be obtained.

Although one embodiment of the present invention has been described above, the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the gist of the present invention. Note that the following modified examples can be combined as appropriate.

<NUM>-<NUM>
The shape of the mask layer is not particularly limited, and various shapes are possible. That is, it is sufficient that at least one opening <NUM> for image capture is formed, and the shape of the opening is also not particularly limited. Accordingly, two or more openings may be formed.

The opening can be formed, for example, as shown in <FIG>. As shown in the drawings, in the region along the opening peripheral edge of the opening <NUM>, an opening peripheral edge region <NUM> in which a plurality of circular dots (mask pieces) <NUM> are arranged in a staggered manner at predetermined intervals is formed (see enlarged view). That is, the opening peripheral region <NUM> is made of the same material (mask material) as the mask layer <NUM>, but the density is lower relative to the percentage by which the same material as the mask layer <NUM> is arranged. The width of the opening peripheral region <NUM>, that is, the distance Z from the peripheral edge of the opening <NUM> is preferably <NUM> or more, and more preferably <NUM> or more. Also, in the opening peripheral region <NUM>, the percentage of the dots <NUM> is preferably <NUM> to <NUM>%, for example. Note that the dots <NUM> can be made of a material different from that of the mask layer <NUM>.

The reason for providing such an opening peripheral region <NUM> is as follows. First, since the coefficient of thermal expansion of the mask layer made of ceramic is different from that of glass, the amount of expansion due to heat absorption is different. For this reason, it was found that when the glass plate is heated together with the mask layer during molding of the glass plate, distortion occurs near the boundary between the mask layer and the region where the mask layer is not formed due to the difference in the amount of expansion. This causes the problem that an image seen through the glass plate is distorted.

In view of this, in the present embodiment, as described above, by forming the opening peripheral region <NUM> formed by the dot pattern, the thermal expansion of the opening peripheral region <NUM> is made smaller than that of the mask layer <NUM>. This makes it possible to prevent the coefficient of thermal expansion from suddenly changing at the boundary between the mask layer <NUM> (edge portion of the opening) and the inside of the opening. That is, the density of the ceramic shifts from the mask layer <NUM> (the edge portion of the opening) where the density of the ceramic is high to the inside of the opening where the ceramic is not formed, through the opening peripheral region <NUM> where the density of the ceramic is low, and therefore the change in the amount of thermal expansion becomes gradual, and therefore it is possible to suppress a case in which distortion occurs in the glass plates <NUM> and <NUM> near the boundary of the opening <NUM>. For this reason, it is possible to suppress the occurrence of distortion in the image acquired by the image capture device <NUM>.

In the example of <FIG>, the opening peripheral region <NUM> is formed by a staggered dot pattern, but a rectangular shape, a polygonal shape, an irregular shape, or the like other than a circular shape may be used as long as the density of the ceramic can be reduced, and these can be arranged in a staggered manner or at predetermined intervals. Also, the size of the dots <NUM> may be changed. Also, linear patterns can be formed at predetermined intervals. In addition, the opening peripheral region can be formed by arranging mask pieces of various shapes at predetermined intervals. For example, the size and shape of the dots can be changed, or the shape of the periphery of the opening can be curved instead of straight.

Note that in the outer glass plate <NUM> and the inner glass plate <NUM> on which the mask layer <NUM> is laminated, a region approximately <NUM> to <NUM> inward from the inner peripheral edge of the opening peripheral edge region <NUM> is a distortion region <NUM> in which distortion may occur, although it is slightly different depending on the heating step and the slow cooling step (the region inside the distortion region <NUM> corresponds to the central region of the present invention). In the example of <FIG>, the inner edge of the distortion region <NUM> is shown by a dotted line. Accordingly, it is preferable to acquire an image by an image capture device further inward relative to the distortion region <NUM>. Note that if the width of the distortion region <NUM> is set to be large, the central region for acquiring a captured image becomes narrow, and therefore the width of the distortion region <NUM> is preferably set within <NUM>.

Note that as shown in <FIG>, if adjacent openings <NUM> are close to each other, for example, if the shortest distance L between the adjacent openings <NUM> is shorter than twice S2 (S2 defined between the adjacent openings) corresponding to each opening <NUM>, the adjacent sheet members <NUM> can be formed so as to be integrated with each other.

Also, as shown in <FIG>, all of the plurality of openings <NUM> can be arranged in the inner portion of the sheet member <NUM>. In this case, each of the above equations can be satisfied in the opening <NUM> arranged near the outer edge of the sheet member <NUM>. Note that as specific numerical values, for example, S1 in <FIG> can be less than <NUM> and S2 can be <NUM> or more. Also, the sheet material can be increased to a size of, for example, <NUM> horizontally × <NUM> vertically. In this case, it is sufficient that the above equation (<NUM>) or (<NUM>) is satisfied at the location where S1+S2 is the smallest among all of the openings <NUM>.

Note that Tts can be calculated by measuring the transmittance/reflectance at wavelengths of <NUM> to <NUM> using a spectrophotometer ("U-<NUM>" manufactured by Hitachi High-Tech) in accordance with ISO <NUM>. From the viewpoint of further improving the heat shielding property, Tts is preferably <NUM>% or less, more preferably <NUM>% or less, and still more preferably <NUM>% or less.

Claim 1:
A laminated glass (<NUM>) on which an information acquisition device (<NUM>) for acquiring information from outside of a vehicle by emitting and/or receiving light is arrangeable, the laminated glass (<NUM>) comprising:
an outer glass plate (<NUM>);
an inner glass plate (<NUM>);
an interlayer film (<NUM>) arranged between the outer glass plate (<NUM>) and the inner glass plate (<NUM>); and
a mask layer (<NUM>) laminated on at least one of a surface on a vehicle interior side of the outer glass plate (<NUM>) or a surface on a vehicle interior side of the inner glass plate (<NUM>),
wherein the interlayer film (<NUM>) includes:
a colored shade region (<NUM>);
a transparent non-shade region (<NUM>); and
a transparent sheet member (<NUM>) fitted into at least one through hole (<NUM>) formed over the shade region (<NUM>) and the non-shade region (<NUM>),
the mask layer (<NUM>) includes at least one opening (<NUM>) that is formed on an inner side relative to an edge portion of the sheet member (<NUM>) at a position corresponding to the sheet member (<NUM>),
the light of the information acquisition device (<NUM>) passes through the opening (<NUM>),
when a thickness of the laminated glass (<NUM>) at a central point of the sheet member (<NUM>) is defined as H1, a thickness of the laminated glass (<NUM>) at a point that is <NUM> away from the edge portion of the sheet member (<NUM>) on a virtual line extending in a horizontal direction through the central point is defined as H2, and
any point A on an inner edge of the opening (<NUM>), a point B that is the shortest distance from the point A on an outer edge of the sheet member (<NUM>), and a point C at which a virtual line extending from the point A through the point B and an outer edge of the mask layer (<NUM>) intersect each other,
a distance between the point A and the point B is defined as S1, and a distance between the point B and the point C is defined as S2,
when H1 is greater than H2, S1 is smaller than S2 at a location where S1+S2 is minimized, and
when H1 is less than H2, S1 is greater than S2 at a location where S1+S2 is minimized.