JP7029945B2 - Laminated glass - Google Patents

Description

The present invention relates to laminated glass.

On cold days and cold regions, the windshield of a car may become cloudy, which hinders driving. Therefore, various methods for removing fogging of the windshield have been proposed. For example, Patent Document 1 discloses that a bus bar and a heating wire are arranged inside a windshield, and fogging is removed by heat generation thereof.

Japanese Unexamined Patent Publication No. 2016-143450

By the way, the windshield is formed of laminated glass in which a bus bar or the like is arranged together with an adhesive layer between two glass plates. Then, when producing this laminated glass, after arranging the bus bar on the adhesive layer, these are sandwiched between two glass plates and pressure is applied to bond them. However, since a step is generated between the bus bar and the adhesive layer, there is a possibility that air may remain in this step at the time of adhesion. When such air remains, the air becomes visible as bubbles in the finished laminated glass, which causes deterioration of the quality of the product. It should be noted that the generation of such bubbles is a problem that can occur not only when the bus bar is arranged but also when a functional layer such as an infrared reflective film or a dimming film is sandwiched between two glass plates.

By the way, the functional layer can be formed so that its outer peripheral edge coincides with the outer peripheral edge of the glass plate, and in this way, the above-mentioned step does not occur, so that the generation of bubbles can be prevented. Can be done. However, in this case, since the outer peripheral edge of the functional layer is exposed from between the glass plates, water may infiltrate between the glass plates from here. As a result, if the laminated glass swells, the original function of the laminated glass may be lost. Furthermore, there are the following problems. That is, since the edge of each glass plate may be formed in an arc shape in cross section, if the outer peripheral edge of the functional layer coincides with the outer peripheral edge of the glass plate, the adhesive layers may not adhere to each other. This can cause wrinkles in the adhesive layer and the functional layer. Therefore, by locating the position of the outer peripheral edge of the adhesive layer on the center side of the position of the outer glass position (for example, about several mm to 30 mm), it is possible to prevent the ingress of water. However, if the position of the outer peripheral edge of the adhesive layer is set inside the outer peripheral edge of the glass plate in this way, the above-mentioned bubbles may occur.

The present invention has been made to solve the above problems, and to provide a laminated glass in which a functional layer is arranged between two glass plates, which can improve the appearance quality. With the goal.

Item 1: An outer glass plate having a first side and a second side facing the first side.
An inner glass plate that is arranged to face the outer glass plate and has substantially the same shape as the outer glass plate,
An interlayer film arranged between the outer glass plate and the inner glass plate,
The shielding layer formed on the surface of the outer glass plate and
Equipped with
The interlayer film is
With an adhesive layer,
The functional layer supported by the adhesive layer and
Equipped with
At least a part of the outer peripheral edge of the functional layer has an inner portion located inside the outer peripheral edge of the adhesive layer.
The shielding layer is a laminated glass arranged so as to cover at least between the inner portion of the functional layer and the outer peripheral edge of the adhesive layer.

Item 2: The laminated glass of Item 1 in which the shielding layer is located on the surface of the outer glass plate on the intermediate film side.

Item 3: The laminated glass according to Item 2, further comprising a second shielding layer provided on the surface of the inner glass plate opposite to the interlayer film.

Item 4: The laminated glass according to any one of Items 1 to 3, wherein the shielding layer is formed over the entire outer peripheral edge of the outer glass plate.

Item 5: The laminated glass according to any one of Items 1 to 4, wherein the shielding layer is arranged between the outer glass plate and the interlayer film.

Item 6: The laminated glass according to any one of Items 1 to 5, wherein the functional layer has a thickness of 5 to 200 μm.

Item 7: The functional layer is
A first busbar that at least partly extends along the end on the first side.
A second bus bar that at least partly extends along the end on the second side.
A plurality of heating wires arranged so as to connect the first bus bar and the second bus bar,
Equipped with
A part of the outer peripheral edge of the first bus bar and the second bus bar constitutes the inner portion.
Item 2. The laminated glass according to any one of Items 1 to 6, wherein the shielding layer is formed so as to cover both the bus bars and the vicinity thereof.

Item 8: The functional layer further includes both bus bars and a support layer for supporting the heating wire.
Item 7. The laminated glass according to Item 7, wherein the support layer is in contact with the adhesive layer.

Item 9: The laminated glass according to Item 7 or 8, wherein both bus bars are formed by laminating a plurality of metal layers.

Item 10: The laminated glass according to any one of Items 7 to 9, wherein the heating wire has a pitch of 1.25 to 4 mm.

Item 11: The laminated glass according to any one of Items 7 to 10, wherein the heat generation amount of the heating wire is 2.0 W / m or less.

Item 12: The laminated glass according to any one of Items 7 to 11, wherein the thickness of the heating wire is 30 μm or less.

Item 13: The laminated glass according to any one of Items 7 to 12, wherein the width of the surface of the heating wire on the adhesive layer side is 1 to 30 μm.

Item 14: The voltage applied to both bus bars is less than 20V.
The width of the surface of the heating wire on the adhesive layer side has a length equal to or greater than the thickness of the heating wire.
Item 6. The laminated glass according to any one of Items 7 to 13, wherein the width of the heating wire is 9 to 20 μm.

Item 15: The voltage applied to both bus bars is 20 to 50 V.
The width of the surface of the heating wire on the adhesive layer side has a length equal to or greater than the thickness of the heating wire.
Item 6. The laminated glass according to any one of Items 7 to 13, wherein the width of the heating wire is 1 to 10 μm.

According to the laminated glass according to the present invention, even if the functional layer is arranged between two glass plates, the quality of appearance can be improved.

It is a front view of one Embodiment of the laminated glass which concerns on this invention. FIG. 3 is a cross-sectional view taken along the line AA of FIG. It is a figure which shows an example of a heating wire. It is a side view of the furnace through which a molding die passes. It is a top view of a molding die. It is a photograph taken in the vicinity of the bus bar of Reference Example 1. It is a photograph taken in the vicinity of the bus bar of Reference Example 2. It is a photograph taken in the vicinity of the bus bar of Reference Example 3. It is a photograph taken in the vicinity of the bus bar of Reference Example 4. It is a table which shows the specification of the heating wire which concerns on Reference Example 5-16. It is a table which shows the specification of the heating wire which concerns on Reference Example 17-27. It is a front view which shows the other example of the laminated glass of FIG. It is a front view which shows the other example of the laminated glass of FIG.

Hereinafter, an embodiment in which the laminated glass according to the present invention is applied to a windshield will be described with reference to the drawings. FIG. 1 is a plan view of the windshield according to the present embodiment, and FIG. 2 is a cross-sectional view of FIG. As shown in FIGS. 1 and 2, the windshield according to the present embodiment includes an outer glass plate 1, an inner glass plate 2, and an intermediate layer 3 arranged between the glass plates 1 and 2. Notches 21 and 22 are formed at the upper ends and lower ends of the inner glass plate 2, respectively, and the connecting members 41 and 42 extending from the intermediate layer 3 are exposed at the notches 21 and 22 respectively. is doing. Hereinafter, each member will be described.

<1. Overview of laminated glass>
<1-1. Glass plate>
Each of the glass plates 1 and 2 is formed in a rectangular shape in which the lower side 12 is longer than the upper side 11. That is, it is formed in a trapezoidal shape surrounded by an upper side 11, a lower side 12, and both side sides (left side 13, right side 14). Then, as described above, arc-shaped notches are formed at the upper end and the lower end of the inner glass plate 2, respectively. Hereinafter, the notch formed in the upper end portion of the inner glass plate 2 will be referred to as a first notch portion 21, and the notch portion formed in the lower end portion will be referred to as a second notch portion 22. Further, as each of the glass plates 1 and 2, a known glass plate can be used, and it can also be formed of heat ray absorbing glass, general clear glass or green glass, or UV green glass. However, these glass plates 1 and 2 need to realize visible light transmittance in accordance with the safety standards of the country in which the automobile is used. For example, the outer glass plate 1 can secure the required solar absorption rate, and the inner glass plate 2 can adjust the visible light transmittance so as to satisfy the safety standard. The following is an example of the composition of clear glass, heat-absorbing glass, and soda lime-based glass.

(Clear glass)
SiO ₂ : 70-73 mass%
Al ₂ O ₃ : 0.6 to 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 converted to Fe ₂ O ₃ (T-Fe ₂ O ₃ ): 0.08 to 0.14% by mass

(Heat ray absorbing glass)
For the composition of the heat ray absorbing glass, for example, the ratio of total iron oxide (T-Fe ₂ O ₃ ) converted to Fe ₂ O ₃ is set to 0.4 to 1.3% by mass based on the composition of clear glass, and CeO. The ratio of ₂ is 0 to 2% by mass, the ratio of TiO ₂ is 0 to 0.5% by mass, and the skeleton components of glass (mainly SiO ₂ and Al ₂ O ₃ ) are T-Fe ₂ O ₃ and CeO. The composition can be reduced by an increase in ₂ and TiO ₂ .

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

As described above, each of the glass plates 1 and 2 is formed in a rectangular shape, but the ratio of the lengths of the upper side 11 and the lower side 12 may be, for example, 1: 1.04 to 1: 1.5. can. For example, when the upper side is 1200 mm, the lower side can be 1250 to 1800 mm. Specifically, the upper side can be 1195 mm and the lower side can be 1435 mm. The ratio described above is a ratio in a two-dimensional plane when the windshield is projected from the front.

That is, although FIG. 1 gives an example in which the lower side 12 is long, it can also be applied to a windshield having a long upper side 11. For example, in the windshield of a small car for one person, when the upper side is 500 mm, the lower side can be 350 to 450 mm. Specifically, the upper side can be 500 mm and the lower side can be 425 mm.

The thickness of the laminated glass according to the present embodiment is not particularly limited, but from the viewpoint of weight reduction, the total thickness of the outer glass plate 1 and the inner glass plate 2 is preferably 2.4 to 4.6 mm. It is more preferably 2.6 to 3.4 mm, and particularly preferably 2.7 to 3.2 mm. As described above, in order to reduce the weight, it is necessary to reduce the total thickness of the outer glass plate 1 and the inner glass plate 2, so that the thickness of each glass plate is not particularly limited. For example, the thicknesses of the outer glass plate 1 and the inner glass plate 2 can be determined as follows.

The outer glass plate 1 is mainly required to have durability and impact resistance against external obstacles. For example, when this laminated glass is used as a windshield of an automobile, it has impact resistance against flying objects such as pebbles. is necessary. On the other hand, the larger the thickness, the heavier the weight, which is not preferable. From this viewpoint, the thickness of the outer glass plate 1 is preferably 1.0 to 3.0 mm, more preferably 1.6 to 2.3 mm. Which thickness to adopt can be determined according to the use of the glass.

The thickness of the inner glass plate 2 can be made the same as that of the outer glass plate 1, but for example, the thickness can be made smaller than that of the outer glass plate 1 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, more preferably 0.8 to 1.8 mm, and more preferably 0.8 to 1.6 mm. Especially preferable. Further, it is preferably 0.8 to 1.3 mm. As for the inner glass plate 2, which thickness should be adopted can be determined according to the use of the glass.

When the heating wire 314 included in the intermediate layer 3 described later is arranged at the center of the intermediate layer 3 in the thickness direction, the thicknesses 1 and 2 of both glass plates may be different. Which glass plate is thicker depends on the main use of the heating wire 314.

Further, the shapes of the outer glass plate 1 and the inner glass plate 2 according to the present embodiment may be curved shapes. However, when each of the glass plates 1 and 2 has a curved shape, it is said that the sound insulation performance deteriorates as the amount of doubling increases. The amount of doubling is an amount indicating bending of the glass plate, and when a straight line L connecting the center of the upper side and the center of the lower side of the glass plate is set, the largest distance between the straight line L and the glass plate is used. It is defined as the amount of duplication D.

Further, the curved glass plate does not have a large difference in sound transmission loss (STL) in the range of the amount of doubling of 30 to 38 mm, but the frequency band is 4000 Hz or less as compared with the flat glass plate. It can be seen that the sound transmission loss is reduced. Therefore, when producing a curved glass plate, it is preferable that the amount of doubling is small. Specifically, the amount of doubling is preferably less than 30 mm, more preferably less than 25 mm, and particularly preferably less than 20 mm.

Here, an example of a method for measuring the thickness when the glass plate is curved will be described. First, the measurement positions are two points above and below the center line extending vertically along 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 Teclock 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 sandwiched between the thickness gauges for measurement.

<1-2. Middle class>
Subsequently, the intermediate layer 3 will be described. The intermediate layer 3 is composed of three layers including a heat generating layer 31 and a pair of adhesive layers 32 and 33 having the same shape as the glass plates 1 and 2 sandwiching the heat generating layer 31. Hereinafter, the adhesive layer arranged on the outer glass plate 1 side will be referred to as a first adhesive layer 32, and the adhesive layer arranged on the inner glass plate 2 side will be referred to as a second adhesive layer 33.

The heat generating layer 31 includes a plurality of heating wires 314 as described later, thereby removing snow, ice, and fogging generated on the surface of the windshield. On the other hand, the heat generated by the heating wire 314 heats the adhesive layers 32, 33 and the like around the heating wire 314, which may cause flicker when the outside of the vehicle is viewed through the windshield. As described above, the heating wire 314 is required to have a calorific value capable of deicing and the like, and is also required to prevent flicker. Therefore, in the present embodiment, as will be described later, the heating wire 314 is required to generate heat. Dimensions such as quantity, line width, and pitch are set.

As a result of the research of the present inventor, it was found that it is necessary to suppress the temperature of the heating wire 314 and its surroundings to 60 ° C. or lower in order to prevent flicker when looking at the outside of the vehicle through the windshield. For that purpose, it is necessary to reduce the amount of heat generated by the heating wire 314 to some extent. Here, the calorific value can be calculated by the following equation (1). The relationship between the resistance of the heating wire 314 and the length and cross-sectional area of the heating wire 314 is as shown in the equation (2).
W = IV = RI ² = V ² / R (1)
R = ρ (L / A) (2)
However, W: electric power, E: voltage, I: current, R: resistance, L: length, A: cross-sectional area, ρ: electrical resistivity

Therefore, from the above equations (1) and (2), in order to reduce the calorific value, the resistance R is increased, the length L of the heating wire 314 is lengthened, the cross-sectional area A of the heating wire 314 is reduced, and the electrical resistance is reduced. There are measures such as increasing the rate ρ. On the other hand, a certain amount of heat generation is required for deicing and the like. Therefore, when the calorific value of each heating wire 314 decreases, it is necessary to increase the number of heating wires 314 in order to maintain the calorific value of the entire windshield. In consideration of the above points, each member constituting the intermediate layer 3 will be described below.

<1-2-1. Heat generation layer>
First, the heat generating layer 31 will be described. The heat generating layer 31 includes a sheet-shaped base material (support layer) 311 and a first bus bar 312, a second bus bar 313, and a plurality of heating wires 314 arranged on the base material 311. The plurality of heating wires 314 are connected in parallel so that both bus bars 312 and 313 are electrodes. The base material 311 can be formed in a rectangular shape so as to correspond to the glass plates 1 and 2 and the adhesive layers 32 and 33, but it does not necessarily have to have the same shape as the adhesive layers 32 and 33, and both glass plates do not necessarily have the same shape. The shape may be smaller than 1 and 2 (in this case, for example, in the peripheral edge of the base material 311 the portion inside the peripheral edge portion of the glass plate corresponds to the inner portion of the present invention). For example, as shown in FIG. 1, in the vertical direction, the length may be shorter than the length between the notches 21 and 22 so as not to interfere with the notches 21 and 22 of the inner glass plate 2. Further, the length of the base material 311 in the left-right direction can also be shorter than the width of both the glass plates 1 and 2.

<1-2-1-1. Busbar ＞
The first bus bar 312 is formed so as to extend along the upper side of the base material 311. On the other hand, the second bus bar 313 is formed so as to extend along the lower side of the base material 311 but is formed longer than the first bus bar 312. However, each bus bar 312, 313 is more than the notch portions 21 and 22 so that the intermediate layer 3 is not exposed from the notch portions 21 and 22 described above when the intermediate layer 3 is sandwiched between the glass plates 1 and 2. Placed inside. The vertical width of each bus bar 312,313 is preferably, for example, 5 to 50 mm, and more preferably 10 to 30 mm. This is because when the width of the bus bars 312 and 313 is smaller than 5 mm, the calorific value of the bus bar increases and the calorific value of the heating wire 314 decreases, so that the desired calorific value cannot be obtained. On the other hand, if the width of the bus bars 312 and 313 is larger than 50 mm, the bus bars 312 and 313 may protrude from the shielding layer 7 and obstruct the field of view. Further, each bus bar 312 and 313 may not be formed exactly along the base material 311. That is, it does not have to be completely parallel to the edge of the base material 311 and can be curved or the like.

The bus bars 312 and 313 can be formed not only by one layer but also by a plurality of layers. For example, an additional member formed in a band shape similar to each bus bar 312,313 can be formed and superposed on each of the bus bars 312,313. As a result, the thickness of the bus bars 312 and 313 is increased, so that the resistance value can be suppressed to a low level. As a result, heat generation in the bus bars 312 and 313 can be suppressed. The material of the additional member is preferably the same as that of the bus bar 312, 313, whereby the additional member and the bus bar 312, 313 can be integrated when they are overlapped with each other. Further, the additional member can be fixed to the bus bars 312 and 13 by, for example, soldering, but the additional member is not limited thereto.

The plurality of heating wires 314 are formed so as to extend in the vertical direction so as to connect the two bus bars 312 and 313. Further, the plurality of heating wires 314 are arranged substantially in parallel. Each heating wire 314 can be formed in a linear shape, and can also have various shapes such as a corrugated shape. In particular, by forming each heating wire 314 into a sinusoidal shape, the heat distribution becomes uniform, and it is possible to optically prevent the heating wire 314 from obstructing the field of view of the windshield. At this time, the crimp rate of the heating wire 314 can be, for example, 150% or less. The crimp ratio is the ratio of the actual length (length following a curve) of the heating wire 314 to the length between both ends of the heating wire 314 on the heating layer 31. By setting the crimp ratio in this way, L in the equation (2) can be increased. As a result, the resistance R becomes large, so that the amount of heat generated becomes small, and flicker can be suppressed. Although the heating line 314 is drawn in a straight line in the drawing, it may include a waveform as described above.

<1-2-1-2. Heating wire>
The line width of each heating line 314 is preferably 1 to 30 μm, more preferably 5 to 20 μm, and particularly preferably 8 to 15 μm. The smaller the line width of the heating line 314, the harder it is to see, so that it is suitable for the windshield according to the present embodiment. However, if the width of the heating wire 314 is reduced, the cross-sectional area is reduced, so that the calorific value may be reduced as described above. Therefore, the lower limit of the line width of the heating line 314 can be set as described above. On the other hand, when the line width of the heating line 314 is increased, it becomes easier to visually recognize, and the calorific value increases due to the increase in the cross-sectional area. Therefore, the upper limit of the line width of the heating line 314 is set as described above.

However, it can be set as follows depending on the voltage applied between both bus bars 312 and 313. For example, when the voltage is smaller than 20V, the line width of the heating wire 314 is preferably 7 to 30 μm. By setting the line width to 7 μm or more, the cross-sectional area becomes large and the amount of heat generated increases. That is, even when the voltage is smaller than 20 V, the required calorific value (for example, 400 W / m ² or more) can be achieved. On the other hand, by setting the line width to 30 μm or less, the visibility can be lowered, the calorific value per heating line 314 can be suppressed, and as a result, flicker can be prevented. From the viewpoint of flicker, the line width of the heating line 314 is preferably 20 μm or less, and more preferably 15 μm or less.

When the voltage applied between the two bus bars 312 and 313 is 20 to 50 V, it is preferably 1 to 10 μm. By setting the line width to 1 μm or more, the calorific value can be increased. On the other hand, by setting the line width to 10 μm or less, the visibility can be lowered. The line width refers to the line width of the largest portion of the cross-sectional shape of the heating line 314. For example, when the cross-sectional shape of the heating wire 314 is trapezoidal, the width of the lower side is the line width, and when the cross-sectional shape of the heating wire 314 is circular, the diameter is the line width.

The thickness of the heating wire 314 is preferably 30 μm or less, more preferably 20 μm or less, and particularly preferably 10 μm or less. As described above, when the thickness is reduced, the step between the heating wire 314 and the base material 311 becomes smaller, and as will be described later, it is possible to suppress the formation of bubbles in the vicinity of this step during manufacturing. Further, the thickness of the heating wire 314 is preferably smaller than the line width of the heating wire 314. In other words, it is preferable that the aspect ratio of the cross section of the heating wire 314 is 1 or less. This is because if the thickness is larger than the line width of the heating wire 314, the heating wire 314 may fall down on the base material 311, making manufacturing difficult, or there is a risk of disconnection.

On the other hand, the thickness of the heating wire 314 is preferably thin in order to suppress the generation of bubbles as described above, but in order to achieve the required calorific value, the thickness of the heating wire 314 is increased. It is preferable to increase the cross-sectional area. From this point of view, the thickness of the heating wire 314 is preferably 5 μm or more, although there is a possibility that bubbles may be generated. Further, as will be described later, if the thickness of the heating wire 314 is 10 μm or more, more bubbles may be generated. However, if the amount of heat generated per 3141 heating wires is large, flicker may occur. Therefore, as described above, it is preferably 30 μm or less.

The line width and thickness of the heating line 314 can be measured, for example, by multiplying a microscope such as VHX-200 (manufactured by KEYENCE CORPORATION) by 1000 times.

Further, the pitch of the adjacent heating wires 314 is preferably 1.25 to 4.0 mm, more preferably 1.50 to 3.5 mm, and further preferably 2.0 to 3.0 mm. preferable. The pitch is not the length of the gap between the adjacent heating lines 314, but the length obtained by adding the line width of the heating line 314 to the length of the gap between the adjacent heating lines 314.

By setting the upper limit of the pitch in this way, for example, when a predetermined calorific value (for example, 400 W / m ² ) is obtained for the entire windshield, the calorific value W of each heating wire 314 is as described above. Even if the value is reduced, the pitch can be reduced and the number of heating lines 314 can be increased, so that it is possible to prevent a decrease in the amount of heat generated in the entire windshield. On the other hand, as of November 2017 in Japan, there are the following provisions regarding the lower limit of the pitch. That is, in Article 39, Paragraph 3, Item 5 (window glass) of the notification that defines the details of the safety standards for road transport vehicles, among the devices that prevent fogging of the window glass, those embedded in the test area A , "The width of the equipment is 0.03 mm or less and the density is 8 lines / cm (5 lines / cm or less when the conductor is embedded horizontally)", but 8 lines / cm or less In order to satisfy the requirements, it is desirable that the pitch is 1.25 mm or more. When the heating lines 314 are formed in a sinusoidal shape, for example, as shown in FIG. 3, the distance L between the center lines of the heating lines 314 is the pitch of the heating lines 314. In this case, the distance L between the center lines D of the waves of the adjacent heating lines 314 can be set to be twice or more the amplitude A of each heating line 314. Further, the amplitude A is not particularly limited, but can be, for example, 3 mm or more.

Regarding the lower limit of the pitch of the heating wire 314, the following points are also taken into consideration. That is, it has been found that when the pitch is small, the above-mentioned bubbles are likely to occur. Specifically, it has been found that when the pitch is smaller than 1.25 mm, bubbles tend to remain. Further, when bubbles are generated on the peripheral edges of the bus bars 312 and 313, the bubbles can be hidden by the shielding layer described later, but when bubbles are generated on the peripheral edges of the heating wire 314, they cannot be hidden. From this, the pitch of the heating wire is preferably 1.25 mm or more, and more preferably 2.0 mm or more.

Further, even if the pitch of the heating wire 314 is increased in order to suppress the generation of bubbles, bubbles are generated at the edge of the heating wire 314, for example, at the intersection of the side surface of the heating wire 314 and the base material 311. Easy to remain. On the other hand, for example, when the base material 311 is formed by PVB, bubbles may be dissolved in PVB, which is preferable. However, not all bubbles are melted, and the unmelted bubbles may move to the bus bar 321 and 313 side along the heating line 314 and remain on the peripheral edge of the bus bar 312 and 313. Therefore, considering the behavior of such bubbles, it is meaningful to hide the bus bars 312 and 313 with the shielding layer 7.

The heating wire 314 may be formed in a sinusoidal shape. In addition, the positions of the sinusoidal irregularities may differ between the adjacent heating wires 314, or the pitch of the irregularities may differ. In these cases, the pitch of the heating wires 314 can be obtained by counting the number n of the heating wires 314 in the predetermined region. For example, when the predetermined region is a rectangular region having a side of 200 mm and 101 heating wires 314 are arranged in the region, the pitch can be determined to be 200 / (101-1) = 2 mm. .. Further, the predetermined region is preferably within the range of the test region A defined by JIS R3212. This is because the test area A in JIS R3212 is an area for performing a test such as fluoroscopic distortion, and it is highly necessary to prevent flicker, which is an effect of the present application, in that area.

Further, the length of the heating wire 314 can be, for example, 1000 mm or more. Alternatively, it may be 1100 mm or more, or 1200 mm or more. Further, the resistance of the heating wire 314 is preferably 30 Ω or more, more preferably 90 Ω or more. By increasing the length of the heating wire in this way, the resistance R increases based on the equation (2), so that the calorific value becomes small and flicker can be suppressed.

Here, the measurement of the resistance R of the heating wire 314 will be described. The measurement can be performed using a commercially available electric resistance measuring instrument, and as an example, a digital multimeter 73200 series (manufactured by YOKOGAWA) can be mentioned. In the measurement, first, the heating wire to be measured is selected. Next, one terminal of the electric resistance measuring instrument is connected in the vicinity of the bus bar 312 of the heating wire, and the other terminal is connected in the vicinity of the bus bar 313 of the heating wire. If the heating wire is sandwiched between the outer glass plate 1 and the inner glass plate 2 and the terminal of the electric resistance measuring instrument cannot be connected to the heating wire as shown in FIG. 1, the outer glass plate 1 or the inner glass plate 1 or the inner glass plate 2 can be destroyed and the resistance R of the heating wire 314 can be measured. Further, for example, when the heating wire to be measured and the heating wire adjacent to the heating wire are connected by a bridge (not shown), the resistance R of the heating wire to be measured is increased after the bridge is cut. Measure.

Further, the calorific value per unit length in each heating line 314 is, for example, 2.0 W / m or less when a voltage of, for example, 13.5 V or 48 V is applied between the two bus bars 312 and 313. Is more preferable, 1.5 W / m or less is more preferable, and 1.0 W / m or less is particularly preferable. When it is 2.0 W / m or less, flicker can be suppressed. More specific ranges include, for example, 1.5 W / m or more and 2.0 W / m or less, 1.35 W / m or more and 1.5 W / m or less, 1.20 W / m or more and 1.35 W / m or less. The range can be 0 W / m or more and 1.20 W / m or less, 0.8 W / m or more and 1.0 W / m or less, or 0.5 W / m or more and 0.8 W / m or less. Then, using such a heating wire 314, the calorific value per unit area in the windshield is preferably 300 to 600 W / m ² in order to effectively prevent anti-fog and thaw, and in particular, It is more preferably 400 W / m ² or more, and particularly preferably 500 W / m ² or more.

<1-2-1-3. Heat-generating layer material>
Next, the material of the heat generating layer 31 will be described. The base material 311 is a transparent film that supports both bus bars 312 and 313 and the heating wire 314, and the material thereof is not particularly limited, but for example, polyethylene terephthalate, polyethylene, polymethylmethacrylate, polyvinyl chloride, polyester, and polyolefin. , Polycarbonate, polystyrene, polypropylene, nylon and the like. Alternatively, it can also be formed by polyvinyl butyral resin (PVB), ethylene vinyl acetate (EVA), or the like. Further, both busbars 312, 313 and the heating wire 314 can be formed of the same material, such as copper (or tin-plated copper), gold, aluminum, magnesium, cobalt, tungsten, silver, or alloys thereof. , Can be made of various materials. Of these, it is particularly preferable to use silver, copper, gold, and aluminum, which are materials having an electrical resistivity of 3.0 × 10 ^-8 Ωm or less. When the electrical resistivity of the heating wire 314 is lowered in this way, the resistance R becomes smaller based on the equation (2), so that the calorific value tends to increase. However, flicker can be suppressed by adjusting the pitch, length, cross-sectional area, and line width of the heating wire 314.

Subsequently, a method of forming both bus bars 312 and 313 and the heating wire 314 will be described. As long as the width of both the bus bars 312 and 313 and the heating line 314 is 10 μm or more, the conductive material may be printed directly on the glass plates 1 and 2. In this case, since the glass plate can be directly heated to form a heating wire, that is, it is not necessary to heat the interlayer film when the heating wire 314 is formed, the interlayer film is deformed and the occurrence of fluoroscopic distortion is suppressed. Can be done. Further, it can be formed by arranging a thin wire (wire or the like) formed in advance on the base material 311. In particular, in order to make the line width of the heating wire 314 thinner, a pattern is formed on the base material 311. Therefore, the heating wire 314 can be formed. The method is not particularly limited, but can be formed by various methods such as printing, etching, and transfer. At this time, the bus bars 312 and 313 and the heating wire 314 can be formed separately, or these can be integrally formed. In addition, "integral" means that there is no break (seamless) between the materials and there is no interface.

Further, both bus bars 312 and 313 are formed on the base material 311, and the base material 311 in the portion corresponding to the bus bars 312 and 313 is peeled off and removed, leaving the base material 311 for the heating wire 314. The heating wire can then be placed on the substrate between the two busbars.

In particular, when etching is adopted, the following can be used as an example. First, a metal foil is dry-laminated on the base material 311 via a primer layer. As the metal foil, for example, copper can be used. Then, by performing a chemical etching treatment on the metal foil using a photolithography method, both bus bars 312, 313 and a plurality of heating wires 314 can be integrally patterned on the base material 311. In particular, when the line width of the heating wire 314 is to be reduced (for example, 15 μm or less), it is preferable to use a thin metal foil, and a thin metal layer (for example, 5 μm or less) is deposited on the base material 311 by vapor deposition, sputtering, or the like. It may be formed and then patterned by photolithography. The surface of the heating wire 314, that is, the surface on the inner glass plate 2 side is blackened, so that the heating wire 314 can be prevented from being visually recognized from the inside of the vehicle. Materials for blackening include copper nitride, copper oxide, nickel nitride, nickel chromium, and the like, and these materials can be used for blackening by plating.

<1-2-2. Adhesive layer>
Both the adhesive layers 32 and 33 are sheet-like members for sandwiching the heat generating layer 31 and adhering to the glass plates 1 and 2. The two adhesive layers 32 and 33 are formed to have the same size as the two glass plates 1 and 2, but the two adhesive layers 32 and 32 are located at positions corresponding to the notches 21 and 22 of the inner glass plate 2. Notches of the same shape are formed respectively. Further, these adhesive layers 32 and 33 can be formed of various materials, for example, polyvinyl butyral resin (PVB), ethylene vinyl acetate (EVA) and the like. In particular, polyvinyl butyral resin is preferable because it has excellent adhesion to each glass plate and also has excellent penetration resistance. A layer of a surfactant may be provided between the adhesive layers 32 and 33 and the heat generating layer 31. With such a surfactant, the surfaces of both layers can be modified, and the adhesive strength can be improved.

Further, as described above, when the base material 311 is formed smaller than the adhesive layers 32 and 33, the peripheral edges of both the adhesive layers 32 and 33 adhere to each other. Since the same materials are easily adhered to each other, the heat generating layer 31 can be firmly held between the two adhesive layers 32 and 33. However, the shapes of both adhesive layers 32 and 33 are not particularly limited, and may be smaller than the glass plates 1 and 2.

The interlayer film 3 may have another structure. For example, the bus bar 312, 313 and the heating wire 314 can be formed between the adhesive layers 32 and 33 without providing the base material 311 of the heat generating layer 31. Since the base material 311 may have a high haze rate depending on the material, it may reduce the transmittance of the laminated glass. Therefore, by not providing the base material 311, the transmittance of the laminated glass can be increased. Further, the adhesive layers 32 and 33 may be either one or the other. Therefore, for example, the interlayer film 3 can be composed of one adhesive layer, bus bars 312, 313, and a heating wire 314. When the adhesive layer is unified, for example, when the first adhesive layer 32 is eliminated, the heating wire 314 comes into contact with the outer glass plate 1. In this case, it is suitable for removing ice and snow from the outer glass plate 1. On the other hand, when the second adhesive layer 33 is eliminated, the heating wire 314 comes into contact with the inner glass plate 2. In this case, it is suitable for removing the fogging generated on the inner glass plate 2. In addition, as described above, additional members can be laminated on the bus bars 312 and 313 to increase the thickness of the bus bars 312 and 313.

The thickness of the additional member is not particularly limited, but since it is used to reduce the resistance value of the bus bars 312 and 313, the thickness may be determined accordingly. For example, it can be 50 to 200 μm (for example, 100 μm). However, when the additional member is used, the above-mentioned bubbles are likely to occur.

<1-2-3. Intermediate layer thickness>
The total thickness of the intermediate layer 3 is not particularly specified, 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 to have. Further, the thickness of the base material 311 of the heat generating layer 31 is preferably 5 to 200 μm, more preferably 5 to 100 μm. It should be noted that the above-mentioned foam may be generated even if the base material 311 is provided.

On the other hand, the thickness of each of the adhesive layers 32 and 33 is preferably larger than the thickness of the heat generating layer 31, specifically, 0.05 to 2.0 mm, and 0.05 to 1.0 mm. It is more preferable to have. Further, although the details will be described later, it is preferable that the thickness of each of the adhesive layers 32 and 33 is small in consideration of the ease of heat dissipation from the heating wire 314 to the glass plates 1 and 2, and specifically, 0. It is preferably 05 to 0.4 mm. The thicknesses of both the adhesive layers 32 and 33 may be the same or different. When heat dissipation is taken into consideration, for example, the thickness of the first adhesive layer 32 can be 30 to 70 μm (for example, 50 μm), and the thickness of the second adhesive layer 33 can be 500 to 900 μm (for example, 760 μm). In this case, since the thickness of the first adhesive layer 32 is small, the heat from the heating wire 314 is easily transferred to the outer glass plate 1, and the deicing performance is improved. On the other hand, if this thickness is reversed between the first adhesive layer 32 and the second adhesive layer 33, the heat from the heating wire 314 is easily transferred to the inner glass plate 2, and the anti-fog performance is improved. Since the second adhesive layer 33 and the base material 311 are brought into close contact with each other, the thickness of both bus bars 312 and 313 and the heating wire 314 sandwiched between them is preferably 3 to 20 μm in consideration of this point.

The thicknesses of the heat generating layer 31 and the adhesive layers 32 and 33 can be measured, for example, as follows. First, the cross section of the laminated glass is magnified 175 times and displayed by a microscope (for example, VH-5500 manufactured by KEYENCE CORPORATION). Then, the thicknesses of the heat generating layer 31 and the adhesive layers 32 and 33 are visually specified and measured. At this time, in order to eliminate visual variations, the number of measurements is set to 5 and the average value is the thickness of the heat generating layer 31 and the adhesive layers 32 and 33.

The thicknesses of the heat generating layer 31 and the adhesive layers 32 and 33 of the intermediate layer 3 do not have to be constant over the entire surface, and may be formed into a wedge shape for laminated glass used for a head-up display, for example. In this case, the thickness of the heat generating layer 31 and the adhesive layers 32 and 33 of the intermediate layer 3 is measured at the thinnest portion, that is, the lowermost portion of the laminated glass. When the intermediate layer 3 has a wedge shape, the outer glass plate 1 and the inner glass plate 2 are not arranged in parallel, but such an arrangement is also included in the glass plate in the present invention. That is, in the present invention, for example, the outer glass plate 1 and the inner glass plate 2 when the heat generating layer 31 and the intermediate layer 3 using the adhesive layers 32 and 33 whose thickness increases at a rate of change of 3 mm or less per 1 m are used. Including the placement of.

<1-3. Connection material>
Next, the connecting material will be described. The connecting materials 41 and 42 are for connecting the bus bars 312 and 313 to the connecting terminals (anode terminal or cathode terminal: not shown), and are formed in a sheet shape by a conductive material. Then, a voltage larger than 12V, for example, a power supply voltage of 13.5V is applied to the connection terminal. Hereinafter, the connecting material connected to the first bus bar 312 will be referred to as a first connecting material 41, and the connecting material connected to the second bus bar 313 will be referred to as a second connecting material 42. Further, since the configurations of both connecting materials 41 and 42 are the same, the first connecting material 41 will be mainly described below.

The first connecting material 41 is formed in a rectangular shape and is sandwiched between the first bus bar 312 and the second adhesive layer 33. Then, it is fixed to the first bus bar 312 by a fixing material 5 such as solder. As the fixing material 5, for example, it is preferable to use solder having a low melting point of 150 ° C. or lower so that the fixing material 5 can be fixed at the same time by an autoclave at the time of assembling the windshield described later. Further, the first connecting material 41 extends from the first bus bar 312 to the upper end edge of the outer glass plate 1 and is exposed from the first notch 21 formed in the inner glass plate 2. Then, in this exposed portion, the connection terminal to which the cable extending to the power supply is connected is connected by a fixing material such as solder. In this way, the connection terminals 41 and 42 are fixed to the portions exposed from the notches 21 and 22 of the inner glass plate 2 without protruding from the ends of the glass plates 1 and 2. It has become. Since both the connecting materials 41 and 42 are made of a thin material, they can be bent and then fixed to the bus bar 312 with the fixing material 5 as shown in FIG.

<1-4. Shielding layer>
As shown in FIG. 1, a shielding layer 7 is laminated on a dark-colored ceramic such as black on the peripheral edge of the laminated glass. The shielding layer 7 shields the field of view from the inside or the outside of the vehicle, and is laminated along the four sides of the laminated glass. Both bus bars 312 and 313 are arranged at positions covered by the shielding layer 7. In particular, the shielding layer 7 covers the outer edges of both bus bars 312 and 313 and their vicinity, and at least covers the step between the outer edges of both bus bars 312 and 313 and the base material 311 and its vicinity. When the base material 311 is smaller than the adhesive layers 32 and 33, it covers at least the step between the base material 311 and the adhesive layers 32 and 33 and its vicinity. Reference numeral 7 in the figure indicates the inner edge of the shielding layer 7.

The shielding layer 7 can have various aspects such as, for example, only the outer surface of the outer glass plate 1, only the inner surface of the outer glass plate 1, or the inner surface of the outer glass plate 1 and the inner surface of the inner glass plate 2. If at least the outer glass plate 1 is provided with the shielding layer 7, it is possible to prevent bubbles from being visually recognized from the outside of the vehicle. On the other hand, if the inner glass plate 2 is provided with the second shielding layer, it is possible to prevent bubbles from being visually recognized from the inside of the vehicle. However, whether or not the second shielding layer prevents the visibility of bubbles from the inside of the vehicle depends on the structure of the vehicle. That is, when the bubbles are hidden by fitting the laminated glass into the vehicle body, it is considered that the second shielding layer is unnecessary. However, in order to improve the quality of the laminated glass itself, or when the bubbles are not hidden in the vehicle body, it is preferable to provide a second shielding layer to hide the bubbles from the inside of the vehicle.

＊１，主成分：酸化銅、酸化クロム、酸化鉄及び酸化マンガン
＊２，主成分：ホウケイ酸ビスマス、ホウケイ酸亜鉛 Further, it can be formed of ceramic or various materials, and for example, it can have the following composition.

* 1, Main component: Copper oxide, Chromium oxide, Iron oxide and Manganese oxide * 2, Main component: Bismuth borosilicate, Zinc borosilicate

The ceramic can be formed by a screen printing method, but it can also be produced by transferring a baking transfer film to a glass plate and firing it. When screen printing is adopted, for example, polyester screen: 355 mesh, coat thickness: 20 μm, tension: 20 Nm, squeegee hardness: 80 degrees, mounting angle: 75 °, printing speed: 300 mm / s can be set, and a drying oven. The ceramic can be formed by drying at 150 ° C. for 10 minutes.

Further, the shielding layer 7 can be formed by laminating ceramics or by attaching a shielding film made of a dark resin.

<2. Windshield manufacturing method>
Next, a method for manufacturing the windshield will be described. First, the glass plate production line will be described.

Here, the molding die will be described in more detail with reference to FIGS. 4 and 5. FIG. 4 is a side view of the furnace through which the molding die passes, and FIG. 5 is a plan view of the molding die. As shown in FIG. 5, the molding die 800 includes a frame-shaped mold body 810 that substantially matches the outer shape of both the glass plates 1 and 2. Since the mold body 810 is formed in a frame shape, it has an internal space 820 that penetrates in the vertical direction inside. Then, the peripheral edges of the flat plate-shaped glass plates 1 and 2 are placed on the upper surface of the mold body 810. Therefore, heat is applied to the glass plates 1 and 2 from a heater (not shown) arranged on the lower side via the internal space 820. As a result, both the glass plates 1 and 2 are softened by heating and are curved downward due to their own weight. A shielding plate 840 for shielding heat may be arranged on the inner peripheral edge of the mold body 810, whereby the heat received by the glass plates 1 and 2 can be adjusted. Further, the heater can be provided not only below the molding die 800 but also above the molding die 800.

Then, after the above-mentioned shielding layer 7 is laminated on the flat plate-shaped outer glass plate 1 and the inner glass plate 2, the outer glass plate 1 and the inner glass plate 2 are overlapped and supported by the molding die 800. , As shown in FIG. 4, passes through the heating furnace 802. When heated to near the softening point temperature in the heating furnace 802, both the glass plates 1 and 2 are curved inward from the peripheral edge due to their own weight, and are formed into a curved surface. Subsequently, both the glass plates 1 and 2 are carried into the slow cooling furnace 803 from the heating furnace 802, and the slow cooling process is performed. After that, both the glass plates 1 and 2 are carried out from the slow cooling furnace 803 and allowed to cool.

When the outer glass plate 1 and the inner glass plate 2 are formed in this way, the intermediate layer 3 is subsequently sandwiched between the outer glass plate 1 and the inner glass plate 2. Specifically, first, the outer glass plate 1, the first adhesive layer 32, the heat generating layer 31, the second adhesive layer 33, and the inner glass plate 2 are laminated in this order. At this time, the heat generating layer 31 faces the surface on which the first bus bar 312 and the like are formed toward the second adhesive layer 33 side. Further, the upper and lower ends of the heat generating layer 31 are arranged inside the cutout portions 21 and 22 of the inner glass plate 2. Further, the notches of the first and second adhesive layers 32 and 33 are made to coincide with the notches 21 and 22 of the inner glass plate 2. As a result, the outer glass plate 1 is exposed from the cutout portions 21 and 22 of the inner glass plate 2. Subsequently, the connecting materials 41 and 42 are inserted between the heat generating layer 31 and the second adhesive layer 33 from the notched portions 21 and 22. At this time, solder having a low melting point is applied to the connecting materials 41 and 42 as the fixing material 5, so that the solder is arranged on the bus bars 312 and 313.

In this way, the laminate in which both the glass plates 1 and 2, the intermediate layer 3 and the connecting materials 41 and 42 are laminated is placed in a rubber bag and pre-bonded at about 70 to 110 ° C. while sucking under reduced pressure. The method of pre-adhesion can be other than this, and the following method can also be adopted. For example, the laminate is heated in an oven at 45-65 ° C. Next, this laminate is pressed by a roll at 0.45 to 0.55 MPa. Subsequently, the laminate is heated again in the oven at 80 to 105 ° C. and then pressed again with a roll at 0.45 to 0.55 MPa. In this way, the pre-bonding is completed.

Next, the main bonding is performed. The pre-bonded laminate is subjected to main bonding by an autoclave, for example, at 8 to 15 atm and at 100 to 150 ° C. Specifically, for example, the main bonding can be performed at 14 atm and 135 ° C. Through the above pre-adhesion and main adhesion, both the adhesive layers 32 and 33 are adhered to the glass plates 1 and 2 with the heat generating layer 31 sandwiched between them. Further, the solder of the connecting materials 41 and 42 is melted, and the connecting materials 41 and 42 are fixed to the bus bars 312 and 313. In this way, the laminated glass according to this embodiment is manufactured. It should be noted that a curved windshield can also be manufactured by another method, for example, press working.

<3. How to use the windshield ＞
The windshield configured as described above is attached to the vehicle body, and connection terminals are fixed to the connecting materials 41 and 42. After that, when the connection terminals are energized, a current is applied to the heating wire 314 via the connection materials 41, 42 and the bus bars 312, 313, and heat is generated. By this heat generation, it is possible to remove the fogging on the inner surface of the windshield or to thaw the outer surface of the windshield.

<4. Features>
As described above, according to the present embodiment, the following effects can be obtained.

(1) As described above, the shielding layer 7 covers the outer edges of both bus bars 312 and 313 and their vicinity, and at least covers the step between the outer edges of both bus bars 312 and 313 and the base material 311 and its vicinity. ing. Therefore, the bubbles generated in the step between the bus bars 312 and 313 and the base material 311 can be hidden by the shielding layer 7. Therefore, even if bubbles are generated, they can be visually recognized from the outside of the vehicle.

(2) Further, by adjusting the thicknesses of the bus bar 312, 313, the heating wire 314, and the base material 311, the generation of bubbles can be suppressed. For example, an example of a windshield in which the interlayer film 3 is configured as follows will be described. In the following example, the following heat generating layer 31 is arranged between the adhesive layers 32 and 33. The numbers in the table are thicknesses. The bus bars 312 and 313 and the heating wire 314 are integrally formed and have the same thickness. The appearance of the table below is a photograph of the vicinity of the bus bar.

In Reference Examples 1 to 4, the base material 311 is not provided on the heat generating layer 31, but air remains during manufacturing due to a step between the bus bars 312 and 313 and the heating wire 314 and the adhesive layers 32 and 33. , Bubbles are generated. In Reference Examples 1 and 2, the bubbles are inconspicuous, but in Reference Examples 3 and 4, the bubbles are conspicuous and the range is wide. Therefore, in Reference Examples 3 and 4, although the shielding layer 7 can cover the bus bars 312 and 313, if the range of bubbles is wide, the shielding layer 7 must also be expanded. Therefore, the thickness of the bus bars 312 and 313 and the heating wire 314 is preferably 30 μm or less. When the base material 311 is provided, in addition to the bus bars 312 and 313 and the heating wire 314, a step is also generated depending on the thickness of the base material 311. The thickness of the entire layer (functional layer) 31 is preferably in the range of 5 to 200 μm. Further, when the functional layer includes, for example, a film having a dimming function, it is preferably in the range of 5 to 500 μm.

(3) The present inventor has found that when a laminated glass is heated by applying a voltage to the heating wire 314, when the outside of the vehicle is viewed through the laminated glass, flicker occurs in the object outside the vehicle. As a result of investigating the cause of this, it was found that the refractive index of the resin layer in the vicinity thereof changes due to the heat of the heating wire 314, and distortion occurs. Then, it was found that the change in the refractive index caused flicker.

Furthermore, the present inventor has found that, in particular, when the temperature of the heating wire 314 and its surroundings exceeds about 60 ° C., the above-mentioned flicker occurs. Therefore, in order to prevent the temperature of the heating wire 314 and its surroundings from exceeding about 60 ° C., the present inventor has made it per unit of the heating wire 314 when a voltage of 13.5V is applied between the bus bars 312 and 313. It was found that flicker can be prevented by reducing the calorific value of the above to 2.0 W / m or less. Therefore, in the windshield according to the present embodiment, when a voltage of 13.5 V is applied between the bus bars 312 and 313, the calorific value per unit length of each heating wire 314 is 2.0 W / m or less. Therefore, the temperature of the heating wire 314 and its surroundings can be suppressed to about 60 ° C. or lower, and as a result, flicker when looking at the outside of the vehicle through the windshield can be prevented.

(4) For the heating wire, for example, in the case of a windshield that requires a calorific value of 464 W / m ² for a region of 1180 mm in width and 958 mm in length at a voltage of 13.5 V, set as shown in FIG. Can be done.

The shape of the heating wire 314 for satisfying the calorific value is as shown in Reference Examples 5 to 16 shown in FIG. However, since the pitch of the heating wire 314 is required to be 1.25 mm or more according to the above-mentioned regulations, it is preferable to adopt the heating wires of Reference Examples 15 and 16. Therefore, considering this pitch, the line width of the heating line 314 is preferably 10 μm or more.

Further, when the voltage is 48 V under the same conditions as in FIG. 10, the heating wire can be set as shown in FIG. In this case, in order to prevent flicker, the calorific value per unit length of each heating wire is preferably 2.0 W / m or less. The pitch is preferably 4.0 mm or less. Under such conditions, it is preferable to use the heating wires of Reference Examples 17 to 19 and 21. Then, the line width of the heating line is preferably about 10 μm or less, and more preferably 8 μm or less.

(5) Since both bus bars 312 and 313 and the heating wire 314 are made of the same material, the linear expansion coefficients of both bus bars 312 and 313 and the heating wire 314 are the same. This has the following advantages. When both bus bars 312 and 313 and the heating wire 314 are made of different materials, the linear expansion coefficients are different. Therefore, for example, when these members are separately manufactured and fixed, a harsh heat cycle test or the like is performed. Due to changes in the environment, there is a possibility that the heating wire may come off from the bus bar, or the two glass plates that make up the laminated glass may float from each other due to this. However, as in the present embodiment, both bus bars may occur. If the 312, 313 and the heating wire 314 are made of the same material, such a defect can be prevented.

(6) Since both bus bars 312 and 313 and the heating wire 314 are integrally formed, it is possible to prevent poor contact between the two and, by extension, poor heat generation. The details of the heat generation failure are as follows. Generally, when the glass plate is heated for anti-fog, the current value may be controlled so that the upper limit of the heating temperature is, for example, 70 to 80 ° C. in order to prevent the occurrence of glass cracks. Desired. On the other hand, if there is local heat generation due to the contact resistance as described above, it is necessary to control the current value by using that portion as the upper limit of the heating temperature. As a result, there is a problem that the heating wire cannot be controlled so as to generate sufficient heat as a whole. However, according to the above configuration, since local heat generation can be prevented, the heating wire can also be controlled so as to be able to sufficiently generate heat as a whole.

(7) In the above embodiment, the two connecting materials 41 and 42 are used to connect the bus bars 312 and 313 to the external terminals. For example, a wide bus bar is prepared and the bus bar is connected. It is also conceivable to cut an unnecessary part and then expose a part from the notch portions 21 and 22 to replace the connecting material. However, in this way, it is possible that local heat generation occurs at the corners of the cut bus bar. On the other hand, in the present embodiment, since the separate connecting materials 41 and 42 are fixed to the bus bars 312 and 313, such local heat generation can be prevented.

<5. Modification example>
Although one embodiment of the present invention has been described above, the present invention is not limited to the above embodiment, and various modifications can be made without departing from the spirit of the present invention. In addition, the following modifications can be combined as appropriate.

<5.1>
The heat generating layer 31 can have various shapes. For example, a sheet-shaped heat-generating layer 31 on which both bus bars 312 and 313 and a heating wire 314 are formed is prepared in advance on the base material 311 and cut appropriately to form an appropriate shape, and then both glass plates. It can be placed between 1 and 2. Therefore, for example, if the edges of the glass plates 1 and 2 are curved, the edges of the base material 311 may be curved accordingly. Further, since it is not necessary to completely match the shape of the heat generating layer 31 with the shapes of the glass plates 1 and 2, and the heat generating layer 31 can be arranged only in the portion where the anti-fog effect is desired, various shapes such as smaller shapes than the glass plates 1 and 2 can be obtained. Can be shaped. The glass plates 1 and 2 can also have various shapes other than the perfect rectangle.

In the above embodiment, both bus bars 312 and 313 and the heating wire 314 are arranged on the base material 311. However, at least the heating wire 314 may be arranged. Therefore, for example, both bus bars 312 and 313 can be arranged between the two adhesive layers 32 and 33.

Further, as the configuration of the interlayer film 3, for example, the base material 311 supporting the bus bars 312 and 313 and the heating wire 314 can be arranged between the glass plates 1 and 2 without providing the adhesive layers 32 and 33. In this case, the base material 311 serves as an adhesive layer.

<5.2>
The configuration of the heating wire 314 is not particularly limited, and various aspects are possible. This point will be described with reference to FIG. Since the example of FIG. 12 differs from the above embodiment mainly in the arrangement of the bus bar and the heating wire, only the different parts will be described below, and the same components will be designated by the same reference numerals and the description thereof will be omitted. do.

As shown in FIG. 12, in this example, the plurality of heating wires 6 are arranged in parallel so as to connect both bus bars 312 and 313. Each heating wire 6 is composed of three portions and two folded portions. That is, a position extending upward from the lower end of the first portion 61 extending from the first bus bar 312 to a position close to the second bus bar 313 and the lower end portion of the first portion 61 via the first folding portion 64 and close to the first bus bar 312. It includes a second portion 62 extending to the second portion 62, and a third portion 63 extending downward from the upper end portion of the second portion 62 via the second folded portion 65 and connected to the second bus bar 313. The plurality of heating wires 6 thus formed are lined up at predetermined intervals in the left-right direction of both bus bars 312 and 313.

In the above example, each heating wire 6 can be lengthened by providing the folded portions 64 and 65 on each heating wire. With these, the calorific value in each heating wire 6 can be reduced.

The form of the heating wire 6 is not particularly limited, and in the present embodiment, it is formed so as to have two folded portions 64 and 65, but three or more folded portions are provided and both bus bars 212 and 213 are provided. The length of the heating wire 6 extending between them can be further increased.

<5.3>
Further, in order to lengthen each heating line 314, a relay bus bar as shown in FIG. 13 can be provided. This point will be described in detail.

As shown in FIG. 9, in this windshield, the first bus bar 312 is arranged on the left side of the lower side 12 of each of the glass plates 1 and 2, and the second bus bar 313 is arranged along the right side of the lower side 12. .. In addition to this, a strip-shaped first relay bus bar 71 on the left side of the upper side 11 of the glass plates 1 and 2, and a strip-shaped second relay bus bar 72 between the first and second bus bars 312 and 313 on the lower side 12, the glass plate 1, A band-shaped third relay bus bar 73 is provided on the right side of the upper side 11 of 2. The first relay bus bar 71 is arranged at a position facing the first bus bar 312 and the second relay bus bar 72, and is formed to have substantially the same length from the left end portion of the first bus bar 312 to the vicinity of the center of the second relay bus bar 72. ing. Further, the third relay bus bar 73 is arranged at a position facing the second relay bus bar 72 and the second bus bar 313, and has substantially the same length from the left end portion of the first bus bar 312 to the vicinity of the center of the second relay bus bar 72. It is formed.

The plurality of heating wires 6 are composed of four parts. That is, the plurality of heating wires 6 are the first portion 601 connecting the first bus bar 312 and the first relay bus bar 71, and the second portion 602 connecting the first relay bus bar 71 and the second relay bus bar 72, respectively. It is composed of a third portion 603 that connects the second relay bus bar 72 and the third relay bus bar 73, and a fourth portion 604 that connects the third relay bus bar 73 and the second bus bar 313. The plurality of first portions 601 extend upward substantially in parallel from the first bus bar 312 and are connected to the left half of the first relay bus bar 71. The plurality of second portions 602 extend downward substantially in parallel from the right half of the first relay bus bar 71, and are connected to the left half of the second relay bus bar 72. Further, the plurality of third portions 603 extend substantially in parallel from the left half of the second relay bus bar 72 upward and are connected to the third relay bus bar 73. The plurality of fourth portions 604 extend downward substantially in parallel from the right half of the third relay bus bar 73, and are connected to the second bus bar 213.

In the above example, three relay bus bars 71 to 73 are provided between the first bus bar 312 and the second bus bar 313, and a plurality of heating wires 6 arranged in parallel via these are the first bus bar 312 and the first bus bar 312. 2 It is configured to connect to the bus bar 313. Therefore, the length of the heating wire 6 between the first bus bar 312 and the second bus bar 313 can be increased. With these, the calorific value in each heating wire 6 can be reduced.

In this example, both bus bars 312 and 313 are arranged along the lower side 12, but they can also be arranged along the upper side 11. That is, from FIG. 9, both bus bars 312 and 313 and the three relay bus bars 71 to 73 can be arranged at positions upside down. Further, the number of relay bus bars is not particularly limited, and two or four or more can be provided, and both ends of the heating wire are connected to the first bus bar 312 and the second bus bar 313 through all the relay bus bars. You just have to.

<5.4>
Further, adjacent heating wires 314 can be connected to each other by at least one bridge. As a result, for example, even if one heating wire 314 is disconnected, electricity can be supplied from the adjacent heating wire 314. The position and number of bridges are not particularly limited. Further, the shape of the bridge is not particularly limited, and various shapes such as being arranged so as to extend diagonally or having a corrugated shape can be used. The bridge can be formed of the same metal material as the heating wire 314 and integrally formed with the heating wire 314.

<5.5>
The form of the connecting materials 41 and 42 and the configuration of the notched portions 21 and 22 of the inner glass plate 2 are not particularly limited. For example, the inner glass plate 2 is formed with a notch having a thickness as small as that of the connecting materials 41 and 42, and the connecting materials 41 and 42 extending from the bus bars 312 and 313 are folded back at this notch to form the inner glass plate 2. It can also be pasted on the surface. By doing so, it is possible to prevent the connecting materials 41 and 42 from protruding in the surface direction from the end portion of the laminated glass.

<5.6>
The shapes of the glass plates 1 and 2 are not particularly limited, and may be any shape as long as the upper side 11, the lower side 12, the left side 13, and the right side 14 can be specified on the outer shape, and are not necessarily rectangular. Further, each side 11 to 14 may be a curved line as well as a straight line.

<5.7>
In the above embodiment, the bus bars 312 and 313 are arranged along the upper side and the lower side of the glass plate, respectively, but the bus bars are arranged along the left side and the right side of the glass plate so that the heating lines extend in the left-right direction. You can also do it.

<5.8>
In the above embodiment, the heat generating layer 31 is provided as the functional layer according to the present invention, but a functional layer having other functions can also be provided. For example, an infrared reflective film, a dimming film, a crime prevention sheet, a color film, a head-up display film, and the like can be provided. Even when such a functional layer is provided, if a step is formed between the adhesive layers 32 and 33, bubbles may be generated as described above, so that the step is covered with the shielding layer 7. Is needed.

In particular, when an infrared reflective film is used as the functional layer 31, the edges of the film may react with the plasticizer to discolor. Therefore, even when such a functional layer 31 is provided, the discoloration can be shielded by the shielding layer 7.

Films such as infrared reflective films, photochromic films, security sheets, and color films may have wrinkles, especially at the edges of the laminated glass, depending on the elongation of the film. Even in such a case, the wrinkles can be shielded by the shielding layer 7.

<5.9>
The shape of the shielding layer 7 is not particularly limited, and can be formed along the peripheral edge of the laminated glass as in the above embodiment, and at least at a position covering the step between the heat generating layer 31 and the adhesive layers 32 and 33. It suffices if it is arranged.

<5.10>
In the above embodiment, the example in which the laminated glass of the present invention is applied to the windshield of an automobile is shown, but it can be applied to the side glass and the rear glass. Further, the present invention is not limited to automobiles, and can be applied to other vehicles such as trains, windowpanes of buildings, and the like.

1 Outer glass plate 2 Inner glass plate 3 Intermediate layer 31 Heat-generating layer (functional layer)
311 Base material 312 1st bus bar 313 2nd bus bar 314 heating wire

Claims (16)

An outer glass plate having a first side and a second side facing the first side,
An inner glass plate that is arranged to face the outer glass plate and has substantially the same shape as the outer glass plate,
An interlayer film arranged between the outer glass plate and the inner glass plate,
The shielding layer formed on the surface of the outer glass plate and
Equipped with
The interlayer film is
With a pair of adhesive layers,
A functional layer supported between the pair of adhesive layers and having a thickness of 5 to 200 μm,
Equipped with
The functional layer is
A first busbar that at least partly extends along the end on the first side.
A second bus bar that at least partly extends along the end on the second side.
A plurality of heating wires arranged so as to connect the first bus bar and the second bus bar,
Equipped with at least one relay bus bar,
The plurality of heating lines are at least
A portion connecting the first bus bar and the relay bus bar,
A portion connecting the second bus bar and the relay bus bar,
Equipped with
The functional layer is formed smaller than the adhesive layer and is formed.
The peripheral edges of the pair of adhesive layers come into contact with each other,
At least a part of the outer peripheral edge of the functional layer has an inner portion located inside the outer peripheral edge of the outer glass plate.
The shielding layer is at least
Between the inner part of the functional layer and the outer peripheral edge of the adhesive layer,
The first and second bus bars , and the vicinity of the periphery thereof,
A laminated glass arranged so as to cover the vicinity of the relay bus bar and its peripheral edge and the outer peripheral edge of the functional layer. An outer glass plate having a first side and a second side facing the first side,
An inner glass plate that is arranged to face the outer glass plate and has substantially the same shape as the outer glass plate,
An interlayer film arranged between the outer glass plate and the inner glass plate,
The shielding layer formed on the surface of the outer glass plate and
Equipped with
The interlayer film is
With a pair of adhesive layers,
A functional layer supported between the pair of adhesive layers and having a thickness of 5 to 200 μm,
Equipped with
The functional layer is
A first busbar that at least partly extends along the end on the first side.
A second bus bar that at least partly extends along the end on the second side.
A plurality of heating wires arranged so as to connect the first bus bar and the second bus bar,
Infrared reflective film and
Equipped with
The functional layer is formed smaller than the adhesive layer and is formed.
The peripheral edges of the pair of adhesive layers come into contact with each other,
At least a part of the outer peripheral edge of the functional layer has an inner portion located inside the outer peripheral edge of the outer glass plate.
The shielding layer is at least
Between the inner part of the functional layer and the outer peripheral edge of the adhesive layer,
Both bus bars and their periphery, and
Laminated glass arranged so as to cover the outer peripheral edge of the functional layer. An outer glass plate having a first side and a second side facing the first side,
An inner glass plate that is arranged to face the outer glass plate and has substantially the same shape as the outer glass plate,
An interlayer film arranged between the outer glass plate and the inner glass plate,
The shielding layer formed on the surface of the outer glass plate and
Equipped with
The interlayer film is
With a pair of adhesive layers,
A functional layer supported between the pair of adhesive layers and having a thickness of 5 to 200 μm,
Equipped with
The functional layer is
A first busbar that at least partly extends along the end on the first side.
A second bus bar that at least partly extends along the end on the second side.
A plurality of heating wires arranged so as to connect the first bus bar and the second bus bar,
At least one of dimming film, security sheet, color film, head-up display film,
Equipped with
The functional layer is formed smaller than the adhesive layer and is formed.
The peripheral edges of the pair of adhesive layers come into contact with each other,
At least a part of the outer peripheral edge of the functional layer has an inner portion located inside the outer peripheral edge of the outer glass plate.
The shielding layer is at least
Between the inner part of the functional layer and the outer peripheral edge of the adhesive layer,
Both bus bars and their periphery, and
Laminated glass arranged so as to cover the outer peripheral edge of the functional layer. The laminated glass according to any one of claims 1 to 3 , wherein the shielding layer is located on the surface of the outer glass plate on the intermediate film side. The laminated glass according to any one of claims 1 to 4 , further comprising a second shielding layer provided on the surface of the inner glass plate opposite to the interlayer film. The laminated glass according to any one of claims 1 to 5 , wherein the shielding layer is formed over the entire circumference of the outer peripheral edge of the outer glass plate. The laminated glass according to any one of claims 1 to 6 , wherein the shielding layer is arranged between the outer glass plate and the interlayer film. The functional layer further has a support layer for supporting both the bus bars and the heating wire.
The laminated glass according to any one of claims 1 to 7 , wherein the support layer is in contact with the adhesive layer. The laminated glass according to any one of claims 1 to 8 , wherein both bus bars are formed by laminating a plurality of metal layers. The laminated glass according to any one of claims 1 to 9 , wherein the pitch of the heating wire is 1.25 to 4 mm. The laminated glass according to any one of claims 1 to 10 , wherein the heat generation amount of the heating wire is 2.0 W / m or less. The laminated glass according to any one of claims 1 to 11 , wherein the thickness of the heating wire is 30 μm or less. The laminated glass according to any one of claims 1 to 12 , wherein the width of the surface of the heating wire on the adhesive layer side is 1 to 30 μm. The voltage applied to both bus bars is less than 20V.
The width of the surface of the heating wire on the adhesive layer side has a length equal to or greater than the thickness of the heating wire.
The laminated glass according to any one of claims 1 to 13 , wherein the width of the heating wire is 7 to 30 μm. The voltage applied to both bus bars is 20 to 50 V, and the voltage is 20 to 50 V.
The width of the surface of the heating wire on the adhesive layer side has a length equal to or greater than the thickness of the heating wire.
The laminated glass according to any one of claims 1 to 13 , wherein the width of the heating wire is 1 to 10 μm. The functional layer further comprises a plurality of relay busbars.
The plurality of heating lines are at least
A portion connecting the first bus bar and the relay bus bar,
A portion connecting the second bus bar and the relay bus bar,
The part that connects the plurality of relay bus bars and
Have more
The laminated glass according to any one of claims 1 to 15 , wherein the shielding layer is arranged so as to cover the plurality of relay bus bars and the vicinity thereof.

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