JP2019119285A - Windshield - Google Patents

Abstract

To provide a windshield capable of improving an appearance of an end surface when at least one of two glass plates has a wedge shape, and to provide a manufacturing method of the same.SOLUTION: A windshield comprises: a first glass plate having a first surface and a second surface; a second glass plate having a first surface and a second surface, and arranged so as to make the first surface and the second surface of the first glass plate face each other; and an intermediate film held between the first glass plate and the second glass plate. The first glass plate has a first end part and a second end part facing the first end part, and is formed so as to become thin from the first end part to the second end part. An end surface connecting the first surface and the second surface of the first glass plate is formed in a cross-section arc shape, and an end surface connecting the first surface and the second surface of the second glass plate is formed in a cross-section arc shape. An end edge at a second surface side in the end surface of the first glass plate, and an end edge at a first surface side in the end surface of the second glass plate are formed so as to face each other.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a windshield and a method of manufacturing the same.

  The windshield in which the head-up display device is used is generally formed in a wedge shape in order to prevent double images. As described above, there are various methods for forming the windshield into a wedge shape. For example, Patent Document 1 discloses a windshield in which the thickness of the intermediate film and the inner glass plate is made constant and the outer glass plate is formed into a wedge shape. Is disclosed.

JP, 2017-105665, A

  By the way, as above-mentioned, when at least one of an outer side glass plate and an inner side glass plate is wedge shape, the shape of an end surface becomes a problem. Generally, the end faces of the outer glass plate and the inner glass plate are polished in an arc shape, but the contact position with the intermediate film is different between the outer glass plate and the inner glass plate depending on the shape of the polished arc. And there is a problem that the appearance becomes worse. Such a problem is a problem that can not occur when both glass plates are flat. The present invention has been made to solve this problem, and provides a windshield that can make the end face look better when at least one of the two glass plates is wedge-shaped, and a method of manufacturing the same. The purpose is

Item 1. A first glass plate having a first surface and a second surface, and a first surface and a second surface, wherein the first surface and the second surface of the first glass plate are disposed to face each other 2 glass plate,
An intermediate film sandwiched between the first glass plate and the second glass plate;
Equipped with
The first glass plate has a first end and a second end opposite to the first end, and is formed to be thinner in thickness from the first end to the second end.
An end face connecting the first surface and the second surface of the first glass plate is formed in an arc shape in cross section,
An end face connecting the first surface and the second surface of the second glass plate is formed in an arc shape in cross section,
The windshield which is comprised so that the edge by the side of the said 2nd surface in the end face of the said 1st glass plate and the edge by the side of the said 1st surface in the end surface of the 2nd glass plate may face.

Item 2. The second glass plate has a first end and a second end corresponding to the first end and the second end of the first glass plate,
The windshield according to claim 1, wherein the second glass plate is formed to be thinner in thickness from the first end to the second end.

Item 3. The first glass plate and the second glass plate have different concentrations of tin oxide on the first surface and the second surface, respectively.
3. The first glass plate and the second glass plate according to item 1 or 2, wherein the high concentration surfaces of the tin oxide or the low concentration surfaces of the tin oxide are opposed to each other. Windshield.

Item 4. The windshield according to Item 3, wherein the first glass plate and the second glass plate are disposed such that the surfaces with high concentration of the tin oxide face each other.

Item 5. The windshield according to item 1, wherein the windshield is formed of a flat plate in which the thickness of the second glass plate is substantially constant.

Item 6. The first glass plate and the second glass plate have different concentrations of tin oxide on the first surface and the second surface, respectively.
The low concentration surface of the tin oxide in the first glass plate and the low concentration surface of the tin oxide in the second glass plate are disposed to face each other,
Item 6. The windshield according to item 5, wherein at least one of a shielding layer and an antenna is laminated on the second surface of the second glass plate.

Item 7. Streaks are formed on the first glass plate,
7. The windshield according to any one of Items 1 to 6, wherein streaks perpendicular to the streaks of the first glass plate are formed on the second glass plate.

Item 8. At the first end portion, an angle between a tangent line passing through the boundary between the second surface of the first glass plate and the end surface and in contact with the end surface and the second surface is θ 1,
At the second end, an angle formed by a tangent line passing through the boundary between the second surface of the first glass plate and the end surface and in contact with the end surface and the second surface is θ2,
When it prescribes,
The windshield according to any one of Items 1 to 7, which satisfies θ1 = θ2.

Item 9. A first end and a second end, and a first end and a second end opposite to the first end, wherein the thickness decreases from the first end toward the second end. Preparing a first glass plate formed on the
Preparing a second glass sheet having a first surface and a second surface;
Providing a cylindrical grindstone rotatably supported about an axis, wherein the cross-sectional shape of the outer circumferential surface in the axial direction is formed in a radially inward convex arc shape;
Polishing the end face connecting the first surface and the second surface in the first glass plate, wherein the grinding wheel rotates in a state where the second surface and the end face are arranged to be orthogonal to each other Arranging the grindstone so that the axis and the end face are parallel, and then grinding the end face in a circular arc over the entire circumference with the grindstone;
Polishing the end face connecting the first surface and the second surface in the second glass plate, wherein the grinding wheel rotates in a state where the first surface and the end face are arranged to be orthogonal to each other Arranging the grindstone so that the axis and the end face are parallel, and then grinding the end face in a circular arc over the entire circumference with the grindstone;
Placing an intermediate film between the second surface of the first glass plate and the first surface of the second glass plate and applying pressure to integrate them;
How to make a windshield.

  According to the present invention, even when at least one of the two glass plates is wedge-shaped, the appearance of the end face can be improved.

It is a front view showing one embodiment of a windshield concerning the present invention. It is the sectional view on the AA line of FIG. It is sectional drawing of the end surface vicinity of the windshield of FIG. It is a figure explaining an example of the manufacturing method of a float glass board. It is sectional drawing explaining the cutting method of a glass plate. It is sectional drawing of a float glass plate. It is sectional drawing of the windshield of FIG. It is a front view explaining the streak of the windshield of FIG. It is a figure which shows grinding | polishing of a glass plate. It is a figure which shows grinding | polishing of a glass plate. It is sectional drawing of the glass plate after grinding | polishing. It is a top view of the shaping | molding die of a glass plate. FIG. 13 is a side view of the furnace through which the mold of FIG. 12 passes. It is the schematic of a head-up display apparatus. It is sectional drawing which shows the end surface vicinity of the windshield which contrasts with this invention. It is sectional drawing of end surface vicinity of the other windshield of this invention. It is sectional drawing of end surface vicinity of the other windshield of this invention. It is sectional drawing of end surface vicinity of the other windshield of this invention. It is sectional drawing of end surface vicinity of the other windshield of this invention.

<1. Outline of the windshield>
Hereinafter, an embodiment of a windshield of an automobile according to the present invention will be described with reference to the drawings. The windshield according to the present embodiment is used to project light to be irradiated by the head-up display device and to display information.

  FIG. 1 is a front view of a windshield according to the present embodiment, and FIG. 2 is a cross-sectional view taken along line A-A 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 film 3 disposed between the glass plates 1 and 2. ing. And the shielding layer 4 is laminated | stacked on this windshield. Each member will be described below.

<2. Outer glass plate and inner glass plate>
First, the outer glass plate 1 and the inner glass plate 2 will be described. The outer glass plate 1 and the inner glass plate 2 may be known glass plates, and may 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 standard of the country where the automobile is used. For example, the required solar radiation absorptivity can be secured by the outer glass plate 1, and the visible light transmittance can be adjusted by the inner glass plate 2 so that the safety standard is satisfied. Below, an example of a clear glass, a heat ray absorption glass, and a soda lime type glass is shown.

(Clear glass)
SiO ₂ : 70 to 73% by mass
Al ₂ O ₃ : 0.6 to 2.4 mass%
CaO: 7 to 12% by mass
MgO: 1.0 to 4.5 mass%
R ₂ O: 13 to 15% by mass (R is an alkali metal)
Fe total iron oxide in terms of _{2 O 3 (T-Fe 2} O 3): 0.08~0.14 wt%

(Heat absorbing glass)
The composition of the heat ray absorbing glass is, for example, a CeO ratio of 0.4 to 1.3 mass% of total iron oxide (T-Fe ₂ O ₃ ) converted to Fe ₂ O _{3 based} on the composition of the clear glass. ₂ ratio as 0-2 mass%, the proportion of TiO ₂ and 0 to 0.5 wt%, framework component of the glass (mainly, SiO ₂ and Al ₂ O ₃₎ to T-Fe ₂ O _3, CeO _The composition can be reduced by the increase of ₂ and TiO ₂ .

(Soda-lime glass)
SiO ₂ : 65 to 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 to 18% by mass
K ₂ O: 0 to 5% by mass
MgO + CaO: 5 to 15% by mass
_{Na 2 O + K 2 O:} 10~20 wt%
SO ₃ : 0.05 to 0.3% by mass
B ₂ O ₃ : 0 to 5% by mass
Fe total iron oxide in terms of _{2 O 3 (T-Fe 2} O 3): 0.02~0.03 wt%

  The outer glass plate 1 is formed in a trapezoidal shape, and has an upper side (first end) 11, a lower side (second end) 12, a right side 13 and a left side 14. Further, the outer glass plate has a first surface 101 facing the vehicle outer side and a second surface 102 facing the vehicle inner side, and has an end surface connecting the first surface and the second surface. Further, the outer glass plate 1 is formed in a wedge shape whose thickness decreases as it goes from the upper side 11 to the lower side 12. Similarly, the inner glass plate 2 is formed in a trapezoidal shape, and has an upper side 21, a lower side 22, a right side 23 and a left side 24. Further, the inner glass plate also has a first surface 201 facing the vehicle outer side and a second surface 202 facing the vehicle inner side, and has an end face connecting the first surface 201 and the second surface 202. However, unlike the outer glass plate 1, the inner glass plate 2 is formed of a flat plate having a constant thickness.

  The intermediate film 3 described above is disposed between the second surface 102 of the outer glass plate 1 and the first surface 201 of the inner glass plate 2.

  Next, the shapes of the end faces of the outer glass plate 1 and the inner glass plate 2 will be described with reference to FIG. As shown in FIG. 3, the end face 15 of the outer glass plate 1 is polished so that the cross section becomes an arc shape. On the other hand, as with the outer glass plate 1, the inner glass plate 2 is polished so that its end face 25 has an arc shape in cross section.

  Further, the edge S11 on the second surface 102 side of the end surface of the outer glass plate and the edge S21 on the first surface 201 side of the end surface 25 of the inner glass plate 2 are opposed to each other. That is, these edge S11, S21 is formed so that the distance X from the outermost part of the end surface 25 of the inner side glass plate 2 becomes the same in the surface direction of the inner side glass plate 2. As shown in FIG.

  The thickness of the windshield 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 5.0 mm. It is more preferable to set it as 2.6 to 4.6 mm, and it is especially preferable to set it as 2.7 to 3.2 mm. Thus, 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 respective thicknesses of the respective glass plates 1 and 2 are particularly limited. Although not, for example, the thicknesses of the outer glass plate 1 and the inner glass plate 2 can be determined as follows. In addition, the thickness of the glass plates 1 and 2 can be measured by a micrometer.

  The outer glass plate 1 is mainly required to be resistant to external obstacles, to have impact resistance, and to have impact resistance to flying objects such as pebbles. On the other hand, the larger the thickness is, the more the weight increases. From this viewpoint, the thickness of the outer glass plate 1 is preferably 1.8 to 2.3 mm, and more preferably 1.9 to 2.1 mm. Which thickness is adopted can be determined according to the application of the glass. However, since the upper side 11 is thicker than the lower side 12, for example, the thickness of the upper side 11 is 2.5 to 5.0 mm, the thickness of the lower side 12 is 2.6 to 6.7 mm, and the thicknesses of the upper side 11 and the lower side 12 A difference can be made into 0.1-1.7 mm.

  Although the thickness of the inner side glass plate 2 can be made equivalent to the outer side glass plate 1, for example, thickness can be made smaller than the outer side glass plate 1 for weight reduction of a windshield. Specifically, in consideration of the strength of the glass, it is preferably 0.6 to 2.3 mm, preferably 0.8 to 2.0 mm, and particularly preferably 1.0 to 1.4 mm. preferable. Furthermore, it is preferable that it is 0.8-1.3 mm. Also about the inner side glass plate 2, it can be determined according to the use of glass which thickness is employ | adopted.

  Moreover, the shape of the outer side glass plate 1 which concerns on this embodiment, and the inner side glass plate 2 is a curved shape. In the case where the windshield has a curved shape, the sound insulation performance is considered to decrease as the amount of debris increases. The dust amount is an amount indicating the bending of the windshield. For example, when a straight line connecting the center of the upper side and the center of the lower side of the windshield is set, the largest of the distances between the straight line and the windshield is used. Define as the amount of dust.

  Here, an example of a method of measuring the thickness of the windshield 1 will be described. First, the measurement positions are at the upper and lower two places on the center line extending in the vertical direction at the center in the left-right direction of the windshield. Although a measuring instrument in particular is not limited, For example, thickness gauge like SM-112 made by Teclock Co., Ltd. can be used. At the time of measurement, the curved surface of the windshield is placed on a flat surface, and the edge of the windshield is held and measured by the thickness gauge.

<3. Method of manufacturing outer glass plate and inner glass plate>
Next, an example of the manufacturing method of the outer side glass plate 1 and the inner side glass plate 2 is demonstrated, referring FIG. As an example, the outer glass plate 1 and the inner glass plate 2 can be float glass plates manufactured by the float method.

  FIG. 4 is a view showing a method of manufacturing a float glass plate. In FIG. 4, the direction perpendicular to the sheet is the flow direction of the molten glass 55, and the lateral direction is the width direction of the molten glass 55. In FIG. 4, the change in thickness of the molten glass 55 is exaggerated.

  In the float method, the molten glass 55 is continuously supplied on the molten metal 54 such as molten tin, and the supplied molten glass 55 is formed into a strip shape by flowing on the molten metal 54. The glass thus formed is referred to as a glass ribbon 55.

  Then, in order to suppress the contraction of the glass ribbon 55 in the width direction, both ends in the width direction of the glass ribbon 55 are respectively pressed by the pair of rollers 56. A plurality of the pair of rollers 56 are provided at intervals in the flow direction of the glass ribbon 55. The glass ribbon 55 is moved to the downstream side by the rotation of the plurality of pairs of rollers 16.

  The glass ribbon 55 is cooled toward the downstream side, cooled and solidified, and then pulled up from the molten metal 54. And after being annealed, it is cut off. Thus, a float glass plate is obtained. Here, in the float glass plate, the surface in contact with the molten metal 54 is referred to as a bottom surface, and the opposite surface is referred to as a top surface. The bottom and top surfaces may be unpolished. Since the bottom surface was in contact with the molten metal 54, when the molten metal 54 is tin, the concentration of tin oxide contained in the bottom surface is larger than the concentration of tin oxide contained in the top surface. Become.

  In FIG. 4, when the pair of rollers 56 pulls the glass ribbon 55 in the width direction, the thickness of the glass ribbon 55 increases from the both ends in the width direction toward the center. When the glass ribbon 55 thus formed is solidified and then cut, the outer glass plate 1 is obtained. At this time, there are two ways of cutting out the outer glass plate, as shown in FIG. First, as shown in the right side of FIG. 5, the glass ribbon 55 is cut such that the cut surfaces K1 and K2 extend in the vertical direction. The cut surfaces K1 and K2 extend in parallel, and in the outer glass plate 1A thus obtained, the cut surfaces K1 and K2 are orthogonal to the bottom surface. In another method, as shown on the left side of FIG. 5, the glass ribbon 55 is cut so as to form cut surfaces K3 and K4 perpendicular to the top surface. The cut surfaces K3 and K4 extend in parallel, and in the outer glass plate 1B thus obtained, the cut surfaces K3 and K4 are orthogonal to the top surface. Which cutting method is used depends on the required performance of the windseed obtained as described later. In any case, the outer glass plate 1 is cut out such that the thickness of the upper side 11 is large and the thickness of the lower side 12 is small.

  On the other hand, the inner glass plate 2 is also formed by the float method in the same manner as the outer glass plate 1, but is formed by the known method not using the above-described roller. Therefore, the thickness of the inner side glass plate 2 is formed substantially uniformly.

  Further, since the glass ribbon 55 flows on the molten metal 54, a plurality of streaks extending in the flow direction are formed on the surface thereof. And this streak is also formed on the surface of the cooled float glass plate. And as shown in FIG. 6, the wavelike unevenness is formed in the direction of the streaks on the surface of the inner glass plate 2 by the streaks. 6 is a cross section similar to FIG. 4 and shows a cross section orthogonal to the flow direction of the glass sheet. Similar irregularities are also formed on the outer glass plate 1. However, in each of the glass plates 1 and 2, the unevenness of the bottom surface in contact with the molten metal 54 is smaller than the unevenness of the top surface. Here, that the unevenness is small means that the difference between the deepest portion and the uppermost portion of the unevenness is small. Further, on the surface of the glass plate formed by the float method, in addition to the above-described streaks, unellis extending in a direction orthogonal to this are also formed. The unellis has a pitch greater than that of the streaks, and the size is smaller than the unevenness of the streaks.

  And in the windshield concerning this embodiment, as shown in FIG. 7, the 2nd surface 102 of the outer side glass plate 1 and the 1st surface 201 of the inner side glass plate 2 are made into the top surface. As a result, the unevenness of the first surface 101 of the outer glass plate 1 and the second surface 202 of the inner glass plate 2, that is, the surface of the windshield facing the outside is reduced.

  Moreover, in this embodiment, as shown in FIG. 8, the streaks of the outer glass plate 1 and the streaks of the inner glass plate 2 are made to be orthogonal to each other. That is, the streaks 150 of the outer glass plate 1 extend parallel to the upper side 11 and the lower side 12 by the above-described method. On the other hand, since the thickness of the inner glass plate 2 is constant, the direction of the streaks can be adjusted, so that the streaks 250 are cut out from the glass ribbon so as to extend from the upper side 21 to the lower side 22. Thus, the windshield is formed such that the streaks 150 of the outer glass plate 1 and the streaks 250 of the inner glass plate 2 are orthogonal to each other.

  In the manufacture of the outer glass plate 1, if the molding conditions are adjusted, the thickness may be increased from the both ends in the width direction toward the central part, or from one end to the other end in the width direction. It is also possible to increase the thickness as much as possible. The thickness of such a glass ribbon 55 can be adjusted by the circumferential speed of the roller 56 in addition to the tension by the roller 56.

  Next, polishing of the end faces of the outer glass plate 1 and the inner glass plate 2 will be described. The end faces of the glass plates 1 and 2 are formed by grinding with a grindstone. First, as shown in FIG. 5, the outer glass plate 1 is cut out from the glass ribbon 55 so that the second surface 102 and the end surface 15 are orthogonal to each other. Then, the grindstone 7 is brought into contact with the outer glass plate 1 to polish the end face. The grindstone 7 is formed in a cylindrical shape, and is rotatably supported about its axis 71. Moreover, the cross section of the axial direction of the outer peripheral surface 72 of the grindstone 7 is formed in circular arc shape convex in the radial direction inward. That is, the diameters of both ends in the axial direction of the grinding wheel 7 are large, and the diameter in the vicinity of the center in the axial direction is smallest.

  Then, the outer glass plate 1 is supported so that the second surface 102 is horizontal, and while rotating the grindstone 7, the grindstone 7 is extended over the entire circumference of the end surface 15 of the outer glass plate 1 as shown in FIG. Move. At this time, the height in the vertical direction of the grindstone 7 is constant. Further, the incised amount Z of the grindstone 7 is the same over the entire circumference of the outer glass plate. Here, the cutting amount Z is the distance by which the grindstone is moved in the surface direction of the second surface 102 for polishing from the position where the grindstone contacts the edge portion of the second surface 102 of the outer glass plate 1.

  Thus, the end face 15 of the outer glass plate 1 is polished in an arc shape. At this time, the outer glass plate 1 is supported so that the second surface 102 extends horizontally, but since the first surface 101 is supported so as to incline downward from the upper side 11 to the lower side 12, As shown in FIG. 11, the angle between the end face 15 and the first surface 101 and the second surface 102 is formed as follows.

Here, it defines as follows.
The angle between the second surface 102 and the tangent line Z1 contacting the end surface 15 through the boundary S11 between the second surface 102 and the end surface 15 on the upper side 11 is θ1
The angle between the second surface 102 and the tangent line Z2 on the lower side 12 passing through the boundary S12 between the second surface 102 and the end surface 15 and in contact with the end surface 15 is θ2
The angle between the first surface 101 and the tangent line Z3 passing through the boundary S13 between the first surface 101 and the end surface 15 and in contact with the end surface 15 at the upper side 11 is θ3
The angle between the first surface 101 and the tangent line Z4 that passes through the boundary S14 between the first surface 101 and the end surface 15 and contacts the end surface 15 at the lower side 12 is θ4

At this time, θ1 and θ2 among the θ1 to θ4 satisfy the following equation (1).
θ1 = θ2 (1)
This is because the entire circumference of the outer glass plate 1 is polished after the axial position of the grindstone 7 with respect to the second surface 102 is fixed. Moreover, thereby, the outermost parts of the end surface of both the glass plates 1 and 2 can be made into the same position in a surface direction.

  Further, the end face of the inner glass plate 2 is also polished by the grinding wheel 7 in the same manner. That is, the end faces of the outer glass plate 1 and the inner glass plate 2 are polished by the grindstone 7 having the same radius of curvature. At this time, the cut amount of the inner glass plate 2 by the grindstone 7 is the same as that of the outer glass plate 1. The cut amount is the distance by which the grindstone 7 is moved in the surface direction of the first surface 201 for polishing from the position where the grindstone is in contact with the end face 25 of the first surface 201 of the inner glass plate 2. Further, the axial position of the grindstone 7 with respect to the thickness direction of the inner glass plate 2 is also adjusted. As described above, the outer glass plate 1 and the inner glass plate 2 adjust the position of the grindstone 7 in the axial direction while the incised amount of the grindstone 7 is the same. The edge S1 on the second surface 102 side in the end surface of the second embodiment faces the edge S2 on the first surface 201 side of the end surface 25 of the inner glass plate 2.

<4. Intermediate film>
The intermediate film 3 has a substantially constant thickness and is formed of at least one layer. As an example, as shown to the enlarged view of FIG. 2, the soft core layer 31 can be comprised by three layers pinched | interposed by the harder outer layer 32 than this. However, the invention is not limited to this configuration, and it may be formed of a plurality of layers including the core layer 31 and at least one outer layer 32 disposed on the outer glass plate 1 side. For example, a two-layer intermediate film 3 including a core layer 31 and one outer layer 32 disposed on the outer glass plate 1 side, or two or more even outer layers 32 on both sides centering on the core layer 31 Alternatively, the intermediate film 3 may be an intermediate film 3 in which an odd number of outer layers 32 are disposed on one side of the core layer 31 and an even number of outer layers 32 are disposed on the other side. When only one outer layer 32 is provided, it is provided on the side of the outer glass plate 1 as described above, in order to improve the damage resistance against external force from the outside of the vehicle or the outside. In addition, when the number of outer layers 32 is large, the sound insulation performance also increases.

  The hardness is not particularly limited as long as the core layer 31 is softer than the outer layer 32. Although the material which comprises each layer 31 and 32 is not specifically limited, For example, the outer layer 32 can be comprised, for example with polyvinyl butyral resin (PVB). The polyvinyl butyral resin is preferable because it is excellent in adhesion to each glass plate and penetration resistance. On the other hand, the core layer 31 can be made of, for example, an ethylene vinyl acetate resin (EVA) or a polyvinyl acetal resin that is softer than the polyvinyl butyral resin that constitutes the outer layer. By sandwiching the soft core layer, the sound insulation performance can be greatly improved while maintaining the same adhesiveness and penetration resistance as the single layer resin intermediate film.

  Generally, the hardness of the polyvinyl acetal resin is controlled by (a) degree of polymerization of polyvinyl alcohol which is the starting material, (b) degree of acetalization, (c) kind of plasticizer, (d) addition ratio of plasticizer, etc. Can. Therefore, even if it is the same polyvinyl butyral resin by adjusting at least one suitably chosen from those conditions, hard polyvinyl butyral resin used for outer layer 32, soft polyvinyl butyral resin used for core layer 31 It is possible to make different. Furthermore, the hardness of the polyvinyl acetal resin can be controlled also by the type of aldehyde used for acetalization, co-acetalization with a plurality of aldehydes, or pure acetalization with a single aldehyde. Although it can not generally be said, the polyvinyl acetal resin obtained using an aldehyde having a large number of carbons tends to be softer. Therefore, for example, when the outer layer 32 is made of a polyvinyl butyral resin, the core layer 31 contains an aldehyde having 5 or more carbon atoms (for example, n-hexyl aldehyde, 2-ethylbutyraldehyde, n-heptyl aldehyde, A polyvinyl acetal resin obtained by acetalizing n-octyl aldehyde) with polyvinyl alcohol can be used. In addition, when predetermined Young's modulus is obtained, it may be limited to the said resin etc.

  The total thickness of the interlayer 3 is not particularly limited, but is preferably 0.3 to 6.0 mm, more preferably 0.5 to 4.0 mm, and 0.6 to 2.0 mm. Being particularly preferred. The thickness of the core layer 31 is preferably 0.1 to 2.0 mm, and more preferably 0.1 to 0.6 mm. On the other hand, the thickness of each outer layer 32 is preferably 0.1 to 2.0 mm, and more preferably 0.1 to 1.0 mm. In addition, the total thickness of the intermediate film 3 can be made constant, and the thickness of the core layer 31 can be adjusted in this.

  The thicknesses of the core layer 31 and the outer layer 32 can be measured, for example, as follows. First, the cross section of the windshield is enlarged 175 times and displayed by a microscope (for example, Keyence VH-5500). And thickness of core layer 31 and outer layer 32 is specified by visual observation, and this is measured. At this time, in order to eliminate variations due to visual observation, the number of measurements is made five times, and the average value thereof is made the thickness of the core layer 31 and the outer layer 32.

  The total thickness of the interlayer 3 is not particularly limited, but is preferably 0.3 to 6.0 mm, more preferably 0.5 to 4.0 mm, and 0.6 to 2.0 mm. Being particularly preferred. The thickness of the core layer 31 is preferably 0.1 to 2.0 mm, and more preferably 0.1 to 0.6 mm. On the other hand, the thickness of each outer layer 32 is preferably larger than the thickness of the core layer 31, and specifically, preferably 0.1 to 2.0 mm, and 0.1 to 1.0 mm. Is more preferred. In addition, the total thickness of the intermediate film 3 can be made constant, and the thickness of the core layer 31 can be adjusted in this.

  The thicknesses of the core layer 31 and the outer layer 32 can be measured, for example, as follows. First, the cross section of the windshield is enlarged 175 times and displayed by a microscope (for example, Keyence VH-5500). And thickness of core layer 31 and outer layer 32 is specified by visual observation, and this is measured. At this time, in order to eliminate variations due to visual observation, the number of measurements is made five times, and the average value thereof is made the thickness of the core layer 31 and the outer layer 32. For example, a magnified image of the windshield is taken, and the core layer and the outer layer 32 are specified in this to measure the thickness.

  Although the manufacturing method in particular of intermediate film 3 is not limited, for example, after mixing resin components, such as polyvinyl acetal resin mentioned above, a plasticizer, and other additives if needed and kneading it uniformly, each layer is put together The extrusion molding method, and the method of laminating two or more resin films prepared by this method by a pressing method, a laminating method or the like. The resin film before lamination used in the method of laminating by the pressing method, laminating method or the like may have a single layer structure or a multilayer structure. Further, the intermediate film 3 can be formed in one layer in addition to the formation of the plurality of layers as described above.

<5. Shielding layer>
As shown in FIG. 1, a shielding layer 2 is laminated on a dark ceramic such as black on the periphery of the windshield. The shielding layer 4 shields the view from inside and outside the vehicle, and is laminated along the four sides of the windshield.

For example, the shielding layer 4 can have various modes such as only the inner surface of the outer glass plate 1, only the inner surface of the inner glass plate 2, or the inner surface of the outer glass plate 1 and the inner surface of the inner glass plate 2. Moreover, although it can form with a ceramic and various materials, it can be set as the following compositions, for example.
* 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 screen printing, but it can also be produced by transferring a baking transfer film onto a glass plate and baking it. When screen printing is employed, 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, drying furnace Drying at 150 ° C. for 10 minutes can form a ceramic.

  The ceramic is likely to be in close contact with the bottom surface of the glass ribbon 55 described above. This is because the concentration of tin oxide at the bottom surface is high. Therefore, in the case where the shielding layer 4 is formed of ceramic, it is preferable to form the shielding layer 4 on the bottom layer. Therefore, for example, when forming a windshield as shown in FIG. 7, the shielding layer 4 can be formed on the second surface 202 of the inner glass plate 2. The shielding layer 4 can also be formed by laminating a dark-colored resin shielding film as well as laminating ceramics.

<6. Windshield manufacturing method>
Next, a method of manufacturing the windshield will be described. First, the manufacturing line of a glass plate is demonstrated.

  The mold will now be described in more detail with reference to FIG. FIG. 12 is a plan view of the mold. As shown in FIG. 12, this forming die 800 is provided with a frame-like die main 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 penetrating in the vertical direction inside. Then, the peripheral edge portions of the flat 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 the heater (not shown) disposed on the lower side through the internal space. As a result, both the glass plates 1 and 2 are softened by heating and curved downward by their own weight. In addition, the shielding board 840 for shielding heat may be arrange | positioned to the inner periphery of the type | mold main body 810, and the heat which the glass plates 1 and 2 receive can be adjusted by this. Also, the heater can be provided not only below the forming die 800 but also above it.

  Next, the molding method will be described with reference to FIG. FIG. 13 is a side view of the furnace through which the mold passes. First, the shielding layer 2 described above is laminated on the outer glass plate 1 and the inner glass plate 2 before bending. Next, the outer glass plate 1 and the inner glass plate 2 are stacked and, while being supported by the forming die 800, pass through the heating furnace 802 as shown in FIG. When heated to near the softening point temperature in the heating furnace 802, both the glass plates 1 and 2 are curved downward inside by the own weight than the peripheral portion and are formed into a curved surface. Subsequently, both the glass plates 1 and 2 are carried from the heating furnace 802 to the annealing furnace 803, and annealing is performed. Thereafter, both glass plates 1 and 2 are carried out of the annealing furnace 803 to the outside and allowed to cool.

  Thus, when the outer glass plate 1 and the inner glass plate 2 are formed, the intermediate film 3 is subsequently sandwiched between the outer glass plate 1 and the inner glass plate 2. The intermediate film 3 has a slightly larger shape than the outer glass plate 1 and the inner glass plate 2. Thus, the outer edge of the intermediate layer 3 is in a state of protruding from the outer glass plate 1 and the inner glass plate 2.

  Next, the laminated body in which both the glass plates 1 and 2 and the intermediate film 3 are laminated is put in a rubber bag and prebonded at about 70 to 110 ° C. while vacuum suction is performed. Other pre-adhesion methods are possible, and the following method may be adopted. For example, the laminate is heated at 45 to 65 ° C. in an oven. Next, this laminate is pressed by a roll at 0.45 to 0.55 MPa. Then, after heating this laminated body again at 80-105 degreeC by oven, it presses with a roll again at 0.45-0.55 MPa. Thus, pre-adhesion is completed.

  Next, main bonding is performed. The pre-bonded laminate is subjected to main bonding by an autoclave at, for example, 8 to 15 atm at 100 to 150 ° C. Specifically, for example, the main adhesion can be performed under the conditions of 14 ° C. and 135 ° C. The intermediate film 3 is adhered to the glass plates 1 and 2 through the above-described pre-adhesion and main adhesion. Finally, when the intermediate film 3 protruding from the outer glass plate 1 and the inner glass plate 2 is cut, a windshield having a cross section as shown in FIG. 3 is manufactured. In addition, the curved windshield can also be manufactured by methods other than this, for example, press work.

<7. Head-up display device>
Next, the head-up display device will be described. A head-up display device (referred to as a HUD device) projects information such as the vehicle speed on a windshield. However, it is known that with this HUD device, a double image is formed by the light projected onto the windshield. That is, since the image visually recognized by reflecting on the inner surface of the windshield and the image visually recognized by reflecting on the outer surface of the windshield are separately viewed, the images are doubled.

  In order to prevent this, the outer glass plate 1 as in this embodiment uses a wedge-shaped windshield. That is, as shown in FIG. 14, in the windshield, at least in the display area where the light is projected from the HUD device 500, the thickness is formed to be smaller as it goes downward. As a result, the light reflected by the inner surface of the windshield (the second surface 202 of the inner glass plate 2) enters the vehicle and the light is reflected by the outer surface of the windshield (the first surface 101 of the outer glass plate 1) Because the light incident on the light substantially matches, the double image is eliminated. The depression angle α of the windshield 1 at this time, that is, the angle between the first surface 101 and the second surface 101 of the outer glass plate 1 depends on the installation angle of the windshield 1, for example, 0.01 It can be made into -0.04 degree (0.2-0.7 mrad).

<8. Feature>
According to the windshield according to the present embodiment, the following effects can be obtained.
(1) As shown in FIG. 3, in the present embodiment, an edge S11 on the second surface 102 side of the end surface 15 of the outer glass plate 1 and an end surface 25 of the inner glass plate 2 are formed in an arc shape. The edge S21 on the side of the first surface 201 is opposed to each other. Therefore, when the intermediate film 3 is sandwiched between them, the position (edge S11) where the intermediate film 3 and the outer glass plate 1 contact and the position where the intermediate film 3 and the inner glass plate 2 contact (edge S21) And the same position from the end face of the windshield. This makes it possible to improve the appearance. On the other hand, for example, as shown in FIG. 15, when the positions of the edges S11 and S21 are different, the appearance becomes worse.

  In particular, when the intermediate film 3 absorbs moisture and swells, if the positions of the edges S11 and S21 are different, the amount of swelling toward the outer glass plate 1 and the inner glass in the vicinity of the edges S11 and S21 The amount of swelling on the side of the plate 2 will be different, and the appearance will be worse.

  Further, since the axial position of the grindstone 7 with respect to the second surface 102 is constant when the end surface 15 of the outer glass plate 1 is polished, the positions of the edges S11 and S12 of the end surface 15 on the second surface 102 side are The same can be made over the entire circumference of the outer glass plate 1. As a result, the end edges S11 and S12 can easily be made to face the end edge S21 of the end surface 25 on the first surface 201 side of the inner glass plate 2.

(2) In the above embodiment, the bottom surface with small unevenness due to streaks is the outer surface of the windshield. That is, since the two outer surfaces of the windshield both have small irregularities, it is possible to reduce perspective distortion when the object outside the vehicle is viewed from inside the vehicle through the windshield.

(3) In the said embodiment, both the glass plates 1 and 2 are arrange | positioned so that the streak 150 of the outer side glass plate 1 and the streak 250 of the inner side glass plate 2 may orthogonally cross. On the other hand, for example, when the streaks 150 and 250 of both glass plates 1 and 2 extend in the same direction, the streaks on the outer surface of the windshield and the streaks on the outer surface combine, and the entire windshield There is a possibility that the change in thickness as This may increase perspective distortion. Therefore, in the present embodiment, since the streaks 150 and 250 of both the glass plates 1 and 2 are orthogonal to each other, it is possible to prevent an increase in unevenness and thereby suppress perspective distortion.

<9. Modified example>
As mentioned above, although one Embodiment of this invention was described, this invention is not limited to the said embodiment, A various change is possible unless it deviates from the meaning. And several modification shown below can be combined suitably.

<9-1>
In the above embodiment, the end face 15 and the second face 102 are made orthogonal to each other with respect to the outer glass plate 1 before the end face is polished, but for example, as shown in FIG. The end face 15 can also be polished so that the end faces S11 and S21 face each other, with the one face 101 being orthogonal to the one face 101.

<9-2>
In the said embodiment, although the inner side glass plate 2 is made flat, as shown in FIG. 17, the inner side glass plate 2 can also be formed in a wedge shape similarly to the outer side glass plate 1. Also in this case, the edges S11 and S21 are arranged to face each other. Moreover, the inner side glass plate 2 can be made into wedge shape, and the outer side glass plate 1 can also be made into flat form.

<9-3>
Further, as shown in FIG. 18, the outermost portions of the end edges 15 and 25 of the outer glass plate 1 and the inner glass plate 2 may not necessarily coincide with each other or may be shifted. Even if such a deviation occurs, the same effect as that of the above embodiment can be obtained as long as the edges S11 and S21 face each other.

<9-4>
In the said embodiment, although the end surface whole of each glass plate is formed in a cross-sectional circular arc shape and the cross section of an end surface is made only to a curve, it is not limited to this. That is, only the corner portions between the first surface and the second surface and the end face of each glass plate can be polished in an arc shape, and the portion between the corner portions can be formed linearly in the cross section of the end face. Therefore, not only when the entire end face is formed into an arc shape, but also when only the corner portions are formed into an arc shape as described above or when the corner portions are chamfered, “the end face is formed into an arc shape according to the present invention If the edges are opposed to each other, the effect of improving the appearance as in the above embodiment can be obtained. Further, the arc shape is formed by arcs of the same radius of curvature, and includes cases where arcs of a plurality of radius of curvature are combined. Moreover, the "edge" which concerns on this invention means the position where a curve is started.

<9-5>
In the said embodiment, although the outer side glass plate 1 and the inner side glass plate 2 are arrange | positioned so that top surfaces may oppose, it is not limited to this. For example, the bottom surfaces can be arranged to face each other. Also, the top surface and the bottom surface can be arranged to face each other.

  As described above, when the bottom surface is the outer surface of the windshield, there is an advantage that the perspective distortion can be suppressed, but it is advantageous to laminate the shielding layer 4 of ceramic from the bottom surface. Therefore, depending on the application, it may be considered which surface is to be opposed. In addition to the shielding layer 4, such a bottom surface is also suitable for laminating an antenna element made of, for example, copper or silver by printing or the like.

<9-6>
In the said embodiment, although it is made for the crosses of the outer side glass plate 1 and the inner side glass plate 2 to be orthogonal, it can also be made parallel.

<9-7>
The shape of the shielding layer 4 is not particularly limited, and various shapes are possible. For example, a shielding layer provided with a window can be formed to allow light emission by a sensor and external photographing by a camera.

<9-8>
The method of forming the outer glass plate 1 and the inner glass plate 2 in a wedge shape is not particularly limited, and methods other than those described above are also possible.

<9-9>
In the above embodiment, the edge of the intermediate film 3 is cut so as to substantially coincide with the outermost portions of the outer glass plate 1 and the inner glass plate 2, but as shown in FIG. It is also possible to cut the intermediate film 3 inside the outermost part of the glass plate 2, for example, in the vicinity of the edges S11 and S21 described above.

1 Outer glass plate (first glass plate)
2 inner glass plate (second glass plate)
3 Interlayer

Claims (9)

A first glass plate having a first surface and a second surface, and a first surface and a second surface, wherein the first surface and the second surface of the first glass plate are disposed to face each other 2 glass plate,
An intermediate film sandwiched between the first glass plate and the second glass plate;
Equipped with
The first glass plate has a first end and a second end opposite to the first end, and is formed to be thinner in thickness from the first end to the second end.
An end face connecting the first surface and the second surface of the first glass plate is formed in an arc shape in cross section,
An end face connecting the first surface and the second surface of the second glass plate is formed in an arc shape in cross section,
The windshield which is comprised so that the edge by the side of the said 2nd surface in the end face of the said 1st glass plate and the edge by the side of the said 1st surface in the end surface of the 2nd glass plate may face. The second glass plate has a first end and a second end corresponding to the first end and the second end of the first glass plate,
The windshield according to claim 1, wherein the second glass plate is formed to be thinner in thickness from the first end to the second end. The first glass plate and the second glass plate have different concentrations of tin oxide on the first surface and the second surface, respectively.
The first glass plate and the second glass plate according to claim 1 or 2, wherein the surfaces with high concentration of tin oxide or the surfaces with low concentration of tin oxide are opposed to each other. Windshield.   The windshield according to claim 3, wherein the first glass plate and the second glass plate are arranged such that the high concentration surfaces of the tin oxide face each other.   The windshield according to claim 1, wherein the windshield is formed of a flat plate in which the thickness of the second glass plate is substantially constant. The first glass plate and the second glass plate have different concentrations of tin oxide on the first surface and the second surface, respectively.
The surface of the first glass plate having a low concentration of tin oxide and the surface of the second glass plate having a low concentration of tin oxide are arranged to face each other,
The windshield according to claim 5, wherein at least one of a shielding layer and an antenna is laminated on the second surface of the second glass plate. Streaks are formed on the first glass plate,
The windshield according to any one of claims 1 to 6, wherein streaks orthogonal to the streaks of the first glass plate are formed on the second glass plate. At the first end portion, an angle between a tangent line passing through the boundary between the second surface of the first glass plate and the end surface and in contact with the end surface and the second surface is θ 1,
At the second end, an angle formed by a tangent line passing through the boundary between the second surface of the first glass plate and the end surface and in contact with the end surface and the second surface is θ2,
When it prescribes,
The windshield according to any one of claims 1 to 7, which satisfies θ1 = θ2. A first end and a second end, and a first end and a second end opposite to the first end, wherein the thickness decreases from the first end toward the second end. Preparing a first glass plate formed on the
Preparing a second glass sheet having a first surface and a second surface;
Providing a cylindrical grindstone rotatably supported about an axis, wherein the cross-sectional shape of the outer circumferential surface in the axial direction is formed in a radially inward convex arc shape;
Polishing the end face connecting the first surface and the second surface in the first glass plate, wherein the grinding wheel rotates in a state where the second surface and the end face are arranged to be orthogonal to each other Arranging the grindstone so that the axis and the end face are parallel, and then grinding the end face in a circular arc over the entire circumference with the grindstone;
Polishing the end face connecting the first surface and the second surface in the second glass plate, wherein the grinding wheel rotates in a state where the first surface and the end face are arranged to be orthogonal to each other Arranging the grindstone so that the axis and the end face are parallel, and then grinding the end face in a circular arc over the entire circumference with the grindstone;
Placing an intermediate film between the second surface of the first glass plate and the first surface of the second glass plate and applying pressure to integrate them;
How to make a windshield.