Glass sheets, laminated glass, vehicle window glass, and architectural window glass

Abstract

A glass plate having the following composition: 70% ≦ SiO2 ≦ 85%, 0.0% ≦ Al2O3 ≦ 10%, 0.0% ≦ B2O3 ≦ 15%, 1.5% ≦MgO ≦ 20%, 0.0% ≦ CaO ≦ 20%, 0.0% ≦ SrO ≦ 5.0%, 0.0% ≦ BaO ≦ 1.0%, 0.0% ≦ ZnO ≦ 5.0%, 1.0% ≦ Li2O ≦ 11%, 0.0% ≦ Na2O ≦ 10%, 0.0% ≦ K2O ≦ 10%, 3.0% ≦ R2O ≦ 11%, 0.01% ≦ Fe2O3 ≦ 1.00% and 2.0% ≦ RO ≦ 20%, and having the following properties: T2 ≦ 1650°C, T12 ≦ 730°C, εr ≦ 6.5 and tanδ ≦ 0.0090.

Description

[Technical Field]

[0001] This invention relates to glass plates, laminated glass, vehicle window glass, and architectural window glass. [Background technology]

[0002] In recent years, the construction of communication infrastructure using 4G (fourth-generation mobile communication system), LTE (Long Term Evolution), and 5G (fifth-generation mobile communication system) has progressed, and furthermore, the widespread adoption of high-speed and high-capacity data communication is expected in the future, including communication using millimeter-wave radar of 30GHz or higher for autonomous driving and other applications.

[0003] However, when installing such millimeter-wave radar inside vehicles or buildings and attempting to transmit millimeter-wave radio waves through window glass, conventional vehicle and building window glass is unsuitable as next-generation glass because it has poor millimeter-wave radio wave transmission properties. This is due to the poor dielectric properties of soda-lime glass, which is currently used in many vehicle and building window panes.

[0004] On the other hand, examples of glass with high millimeter-wave radio wave transmission include glass compositions such as alkali-free glass and slightly alkali-rich glass. For example, Patent Document 1 discloses a window member with excellent radio wave transmission properties that uses alkali-free glass as a radio wave transmitting member. [Prior art documents] [Patent Documents]

[0005] [Patent Document 1] International Publication No. 2020 / 090717 [Overview of the Initiative] [Problems that the invention aims to solve]

[0006] However, because the raw materials for glass compositions such as alkali-free glass and slightly alkali glass are difficult to dissolve, higher temperatures were required for glass melting. Furthermore, when manufacturing glass sheets that require a bending process, such as three-dimensional curved vehicle windows like windshields or aesthetically pleasing curved architectural windows, higher temperatures were required compared to soda-lime glass.

[0007] In view of the above problems, the present invention provides a glass plate with high millimeter-wave transmittance, low melting temperature and bending temperature, and excellent processability, as well as laminated glass, vehicle window glass, and architectural window glass using the glass plate. [Means for solving the problem]

[0008] The glass plate according to an embodiment of the present invention is expressed in mole percentage based on oxide, 70% ≤ SiO2 ≤ 85% 0.0% ≤ Al2O3 ≤ 10% 0.0% ≤ B2O3 ≤ 15% 1.5% ≤ MgO ≤ 20% 0.0% ≤ CaO ≤ 20% 0.0% ≤ SrO ≤ 5.0% 0.0% ≤ BaO ≤ 1.0% 0.0% ≤ ZnO ≤ 5.0% 1.0% ≤ Li2O ≤ 11% 0.0% ≤ Na2O ≤ 10% 0.0% ≤ K2O ≤ 10% 3.0% ≤ R2O ≤ 11% 0.01% ≤ Fe2O3 ≤ 1.00% 2.0% ≤ RO ≤ 20% It contains (R2O represents the total amount of Li2O, Na2O, and K2O, and RO represents the total amount of MgO, CaO, SrO, and BaO), Glass viscosity is 10 2 The temperature T2 at which dPa·s occurs is 1650℃ or less. Glass viscosity is 10 12 Temperature T at which dPa·s occurs 12 The temperature is below 730℃. Relative permittivity (ε) at a frequency of 10 GHzr ) is 6.5 or less, The dielectric loss tangent (tanδ) at a frequency of 10 GHz is 0.0090 or less.

[0009] Furthermore, in a glass plate according to one aspect of the present invention, the average coefficient of thermal expansion at 50°C to 350°C is 40 × 10 -7 / K or higher is also acceptable.

[0010] Furthermore, in a glass plate according to one aspect of the present invention, Al2O3-B2O3 may be > 0.0% in molar percentage based on oxides.

[0011] Furthermore, in a glass plate according to one aspect of the present invention, B2O3 may not be substantially present.

[0012] Furthermore, in a glass plate according to one aspect of the present invention, the molar percentage based on oxides may be 5.0% ≤ B2O3 ≤ 15%.

[0013] Furthermore, in a glass plate according to one aspect of the present invention, the molar percentage based on the oxide may be 0.0% ≤ B2O3 < 5.0%.

[0014] Furthermore, in a glass plate according to one aspect of the present invention, when the thickness is converted to 2.00 mm, the visible light transmittance Tv as defined in ISO-9050:2003 using a D65 light source may be 75% or more.

[0015] Furthermore, in a glass plate according to one aspect of the present invention, when the thickness is converted to 2.00 mm, the total solar radiation transmittance Tts, as defined in ISO-13837:2008 convention A and measured at a wind speed of 4 m / s, may be 88% or less.

[0016] Furthermore, in a glass plate according to one aspect of the present invention, the temperature T 12 However, temperatures below 650°C are also acceptable.

[0017] Furthermore, in a glass plate according to one aspect of the present invention, the relative permittivity (ε) at a frequency of 10 GHz is r ) may be 6.0 or less.

[0018] Furthermore, in a glass plate according to one aspect of the present invention, the molar percentage based on oxides may be 3.0% ≤ Li2O ≤ 10%.

[0019] Furthermore, in a glass plate according to one aspect of the present invention, the molar percentage based on oxides may be 1.8% ≤ MgO ≤ 8.0%.

[0020] Furthermore, in a glass plate according to one aspect of the present invention, the molar percentage based on oxides may be 71% ≤ SiO2 ≤ 85%.

[0021] Furthermore, in a glass plate according to one aspect of the present invention, the molar percentage based on the oxide may be 0.05% ≤ Fe2O3 ≤ 1.00%.

[0022] The laminated glass according to an embodiment of the present invention comprises a first glass plate, a second glass plate, and an interlayer sandwiched between the first glass plate and the second glass plate, wherein at least one of the first glass plate and the second glass plate is the glass plate described above.

[0023] In a laminated glass according to one aspect of the present invention, the total thickness of the first glass plate, the second glass plate, and the interlayer is 6.00 mm or less, and the visible light transmittance Tv, as defined in ISO-9050:2003 using a D65 light source, may be 70% or more.

[0024] Furthermore, in a laminated glass according to one aspect of the present invention, the total thickness of the first glass plate, the second glass plate, and the interlayer may be 6.00 mm or less, and the total solar radiation transmittance Tts, as defined in ISO-13837:2008 convention A and measured at a wind speed of 4 m / s, may be 80% or less.

[0025] Furthermore, in a laminated glass according to one aspect of the present invention, the total thickness of the first glass plate, the second glass plate, and the interlayer film may be 6.00 mm or less, and the maximum value of the radio wave transmission loss S21 when a TM wave with a frequency of 75 GHz to 80 GHz is incident on the first glass plate at an incident angle of 60° may be -4.0 dB or more.

[0026] Furthermore, in a laminated glass according to one aspect of the present invention, the total thickness of the first glass plate, the second glass plate, and the interlayer film may be 6.00 mm or less, and the maximum value of the radio wave transmission loss S21 when a TM wave with a frequency of 75 GHz to 80 GHz is incident on the first glass plate at an incident angle of 45° may be -4.0 dB or more.

[0027] Furthermore, in a laminated glass according to one aspect of the present invention, the total thickness of the first glass plate, the second glass plate, and the interlayer film may be 6.00 mm or less, and the maximum value of the radio wave transmission loss S21 when a TM wave with a frequency of 75 GHz to 80 GHz is incident on the first glass plate at an incident angle of 20° may be -4.0 dB or more.

[0028] A vehicle window glass according to an embodiment of the present invention has the above-mentioned glass plate.

[0029] An architectural window glass according to an embodiment of the present invention has the above-mentioned glass plate.

[0030] Another embodiment of the present invention provides a vehicle window glass having the laminated glass described above. [Effects of the Invention]

[0031] According to the present invention, it is possible to provide glass plates with high millimeter-wave transmittance, low melting temperature and bending temperature, and excellent processability, as well as laminated glass using the glass plates, and window glass for vehicles or buildings. [Brief explanation of the drawing]

[0032] [Figure 1] Figure 1 is a cross-sectional view of an example of laminated glass according to an embodiment of the present invention. [Figure 2] Figure 2 is a conceptual diagram showing how the laminated glass according to an embodiment of the present invention is used as window glass for a vehicle. [Figure 3] Figure 3 is an enlarged view of section S in Figure 2. [Figure 4] Figure 4 is a cross-sectional view along the YY line in Figure 3. [Modes for carrying out the invention]

[0033] Embodiments of the present invention will be described in detail below. In the following drawings, components and parts that perform the same function may be denoted by the same reference numerals, and redundant explanations may be omitted or simplified. Furthermore, the embodiments shown in the drawings are schematic representations for the purpose of clearly illustrating the present invention and do not necessarily accurately represent the size or scale of the actual product.

[0034] In this specification, evaluations such as "high / low millimeter wave radio wave transparency" refer to the radio wave transparency including quasi-millimeter waves and millimeter waves unless otherwise specified, and for example, refer to the radio wave transparency of glass to radio waves with frequencies from 10 GHz to 90 GHz.

[0035] In this specification, "substantially free" of a certain component in glass means that it is not contained except for unavoidable impurities, and that the component is not actively added. Specifically, this means that the content of each of these components in the glass is approximately 100 ppm or less.

[0036] [glass plate] The glass plate according to the embodiment of the present invention is expressed in mole percentage based on oxide, 70% ≤ SiO2 ≤ 85% 0.0% ≤ Al2O3 ≤ 10% 0.0% ≤ B2O3 ≤ 15% 1.5% ≤ MgO ≤ 20% 0.0% ≤ CaO ≤ 20% 0.0% ≤ SrO ≤ 5.0% 0.0% ≤ BaO ≤ 1.0% 0.0% ≤ ZnO ≤ 5.0% 1.0% ≤ Li2O ≤ 11% 0.0% ≤ Na2O ≤ 10% 0.0% ≤ K2O ≤ 10% 3.0% ≤ R2O ≤ 11% 0.01% ≤ Fe2O3 ≤ 1.00% 2.0% ≤ RO ≤ 20% containing (where R2O represents the total amount of Li2O, Na2O, and K2O, and RO represents the total amount of MgO, CaO, SrO, and BaO), the temperature T2 at which the glass viscosity is 10 2 dPa·s is 1650 °C or less, the temperature T 12 at which the glass viscosity is 10 12 dPa·s is 730 °C or less, the relative permittivity (ε r ) at a frequency of 10 GHz is 6.5 or less, and the dielectric loss tangent (tanδ) at a frequency of 10 GHz is 0.0090 or less.

[0037] Hereinafter, the composition ranges of the respective components in the glass plate of the present embodiment will be described. In addition, the composition ranges of the respective components are hereinafter expressed as mole percentages based on oxides, unless otherwise specified.

[0038] SiO2 is an essential component of the glass plate of the present embodiment. The content of SiO2 is 70% or more and 85% or less. SiO2 contributes to an improvement in Young's modulus, making it easier to ensure the strength required for vehicle applications, architectural applications, etc. If SiO2 is too little, it becomes difficult to ensure weather resistance, and the average thermal expansion coefficient becomes too large, which may cause the glass plate to thermally crack. On the other hand, if SiO2 is too much, the viscosity during glass melting may increase, making glass production difficult.

[0039] The SiO2 content in the glass plate of this embodiment is preferably 71% or more, more preferably 72% or more, and even more preferably 73% or more. Furthermore, the SiO2 content in the glass plate of this embodiment is preferably 82% or less, more preferably 80% or less, even more preferably 78% or less, and particularly preferably 76% or less.

[0040] Al2O3 is an optional component of the glass plate in this embodiment. The Al2O3 content is between 0.0% and 10%. The inclusion of Al2O3 ensures weather resistance and prevents thermal cracking of the glass plate due to an increase in the average coefficient of thermal expansion. On the other hand, too much Al2O3 may increase the viscosity of the glass during melting, potentially making it difficult to bend the glass.

[0041] When Al2O3 is included, the Al2O3 content is preferably 0.50% or more, more preferably 1.0% or more, and even more preferably 1.5% or more, in order to suppress phase separation of the glass and improve weather resistance. The Al2O3 content is T 12 From the viewpoint of keeping the noise level low to facilitate glass manufacturing, and from the viewpoint of increasing millimeter-wave radio wave transmittance, a value of 9.0% or less is preferred, 8.0% or less is more preferred, 7.0% or less is even more preferred, 6.0% or less is particularly preferred, and 5.0% or less is most preferred.

[0042] B2O3 is an optional component of the glass plate in this embodiment. The B2O3 content is between 0.0% and 15%. B2O3 is included to improve glass strength and millimeter-wave radio wave transmission, as well as to improve solubility.

[0043] The B2O3 content in the glass plate of this embodiment is preferably 1.0% or more, more preferably 1.5% or more, and even more preferably 2.0% or more.

[0044] Furthermore, if the B2O3 content is too high, alkali elements may volatilize more easily during melting and molding, potentially degrading the glass quality and reducing its acid and alkali resistance. For this reason, the B2O3 content is preferably 14% or less, more preferably 13% or less, even more preferably 12% or less, even more preferably 11% or less, particularly preferably 10% or less, and most preferably 9% or less.

[0045] More specifically, the glass plate of this embodiment is classified into the following three forms depending on the B2O3 content. That is, the first and second forms of the glass plate of this embodiment are forms that substantially do not contain B2O3 or contain a small amount of it, suppressing volatilization during glass melting while maintaining relative permittivity, dielectric loss tangent and T 12 It has the advantage of being able to lower the dielectric constant. Furthermore, the third embodiment of the glass plate in this embodiment is an embodiment that contains a relatively large amount of B2O3, and although there is a concern about volatilization when the glass melts, the relative permittivity, dielectric loss tangent and T 12 It has the advantage of being able to lower the price even further.

[0046] The first embodiment of the glass plate in this model is substantially free of B2O3. This suppresses the volatilization of alkaline components during glass melting.

[0047] Furthermore, the second embodiment of the glass plate in this embodiment contains 0.0% or more and less than 5.0% of B2O3. This suppresses volatilization during glass melting while maintaining relative permittivity, dielectric loss tangent, and T 12 This can be made lower. In the glass plate of this embodiment, the B2O3 content is preferably 1.0% or more, more preferably 1.5% or more, and even more preferably 2.0% or more. Furthermore, the B2O3 content is preferably 4.5% or less, more preferably 4.0% or less, and even more preferably 3.5% or less.

[0048] A third aspect of the glass plate in this embodiment contains 5.0% to 15% of B2O3. This results in the relative permittivity, dielectric loss tangent, and T 12This can be made even lower. In the glass plate of this embodiment, the B2O3 content is preferably 8% or more, more preferably 10% or more, and even more preferably 12% or more. Furthermore, the B2O3 content is preferably 14.5% or less, more preferably 14.3% or less, and even more preferably 14.0% or less.

[0049] In the first and second embodiments of the glass plate of this embodiment, it is preferable that the value obtained by subtracting the content of B2O3 from the content of Al2O3 (Al2O3-B2O3) is greater than 0.0%. That is, Al2O3-B2O3 > 0.0% is preferable. This makes it possible to suppress phase separation during glass plate manufacturing. Al2O3-B2O3 is preferably 0.10% or more, more preferably 0.50% or more, and even more preferably 1.0% or more.

[0050] To increase the transmission rate of millimeter-wave radio waves, the total SiO2 + Al2O3 + B2O3 content of the glass plate in this embodiment, i.e., the sum of the SiO2 content, Al2O3 content, and B2O3 content, is preferably 70% to 95%.

[0051] In this embodiment, further consideration is given to keeping the temperature T2 of the glass plate low to facilitate glass manufacturing. Therefore, the SiO2 + Al2O3 + B2O3 content is more preferably 92% or less, even more preferably 90% or less, particularly preferably 85% or less, and most preferably 80% or less.

[0052] However, if the amount of SiO2 + Al2O3 + B2O3 is too small, the weather resistance may decrease, and the relative permittivity (ε) r ) and the dielectric loss tangent (tanδ) may become too large. For this reason, the SiO2 + Al2O3 + B2O3 content of the glass plate in this embodiment is more preferably 75% or more, and even more preferably 77% or more.

[0053] MgO is an essential component of the glass plate in this embodiment. By including a predetermined amount of MgO as an essential component in the glass plate of this embodiment, the viscosity of the glass is reduced, so the glass viscosity is 10 2This allows for a lower temperature T2 at which dPa·s is obtained, significantly contributing to improved glass solubility. Furthermore, MgO is preferable because it can suppress the increase in dielectric constant compared to CaO.

[0054] The MgO content is 1.5% or more and 20% or less. As mentioned above, MgO is a component that promotes the dissolution of glass raw materials and improves weather resistance and Young's modulus. The MgO content is preferably 1.8% or more, more preferably 2.0% or more, even more preferably 2.5% or more, even more preferably 3.0% or more, particularly preferably 3.5% or more, and most preferably 4.0% or more.

[0055] Furthermore, if the MgO content is 20% or less, T2 and T 12 While controlling it within an appropriate range, the relative permittivity (ε r ) and the increase in dielectric loss tangent (tanδ) can be suppressed. The MgO content is preferably 15% or less, more preferably 10% or less, even more preferably 9.0% or less, particularly preferably 8.0% or less, and most preferably 7.5% or less.

[0056] CaO is an optional component of the glass plate in this embodiment and may be included in a certain amount to improve the solubility of the glass raw material. The CaO content is 0.0% or more and 20% or less. When CaO is included, 2.0% or more is preferred, 2.5% or more is more preferred, 3.0% or more is even more preferred, 3.5% or more is particularly preferred, and 4.0% or more is most preferred. This improves the solubility and moldability (T2 and T) of the glass raw material. 12 (The decrease in) improves.

[0057] Furthermore, by keeping the CaO content below 20%, an increase in glass density is avoided, maintaining low brittleness and strength. This prevents the glass from becoming brittle, and also maintains the relative permittivity (ε) of the glass. r To prevent an increase in the dielectric loss tangent (tanδ), the CaO content is preferably 18% or less, more preferably 16% or less, even more preferably 14% or less, particularly preferably 12% or less, and most preferably 10% or less.

[0058] SrO is an optional component of the glass plate in this embodiment and may be included in a certain amount to improve the solubility of the glass raw material. The SrO content is 0.0% or more and 5.0% or less. When SrO is included, 0.10% or more is preferred, 0.20% or more is more preferred, 0.30% or more is even more preferred, 0.40% or more is particularly preferred, and 0.50% or more is most preferred. This improves the solubility and moldability (T2 decrease, and T) of the glass raw material. 12 (The decrease in) improves.

[0059] Furthermore, by keeping the SrO content below 5.0%, an increase in glass density is avoided, maintaining low brittleness and strength. This prevents the glass from becoming brittle, and also maintains the relative permittivity (ε) of the glass. r To prevent an increase in the dielectric loss tangent (tanδ), the SrO content is preferably 5.0% or less. Furthermore, the SrO content is more preferably 4.0% or less, even more preferably 3.0% or less, particularly preferably 2.0% or less, and most preferably 1.0% or less.

[0060] BaO is an optional component of the glass plate in this embodiment and may be included in a certain amount to improve the solubility of the glass raw material. The BaO content is 0.0% or more and 1.0% or less. If BaO is included, 0.1% or more is preferable, 0.2% or more is more preferable, and 0.3% or more is most preferable. This improves the solubility and moldability (T2 decrease, and T) of the glass raw material. 12 (The decrease in) improves.

[0061] Furthermore, by keeping the BaO content below 1.0%, an increase in glass density is avoided, maintaining low brittleness and strength. This prevents the glass from becoming brittle, and also maintains the relative permittivity (ε) of the glass. r To prevent an increase in the dielectric loss tangent (tanδ), the BaO content is preferably 0.9% or less. More preferably, the BaO content is 0.8% or less, even more preferably 0.6% or less, particularly preferably 0.5% or less, and most preferably substantially absent.

[0062] ZnO is an optional component of the glass plate in this embodiment and may be included in a certain amount to reduce the viscosity of the glass. The ZnO content is 0.0% or more and 5.0% or less. If ZnO is included, 0.10% or more is preferred, 0.50% or more is more preferred, and 1.0% or more is even more preferred.

[0063] Furthermore, by reducing the ZnO content to 5.0% or less, the dielectric constant (ε r The increase in relative permittivity (ε) and dielectric loss tangent (tanδ) can be suppressed. r To suppress increases in ) and dielectric loss tangent (tanδ), the ZnO content is preferably 3.0% or less. Furthermore, the ZnO content is more preferably 2.5% or less, and even more preferably 2.0% or less.

[0064] Li2O is an essential component of the glass plate in this embodiment. By including a predetermined amount of Li2O as an essential component in the glass plate of this embodiment, the viscosity of the glass is reduced, so the glass viscosity is 10 2 This allows us to lower the temperature T2 at which dPa·s occurs, which greatly contributes to improving the solubility of glass.

[0065] The Li2O content is between 1.0% and 11%. As mentioned above, Li2O is a component that improves the solubility of glass, as well as improving Young's modulus and contributing to increased glass strength. Therefore, including Li2O improves the moldability of vehicle windows and architectural windows.

[0066] The Li2O content is preferably 2.0% or more, more preferably 2.5% or more, even more preferably 3.0% or more, particularly preferably 3.5% or more, and most preferably 4.0% or more.

[0067] On the other hand, if the Li2O content is too high, devitrification or phase separation may occur during glass manufacturing, potentially making production difficult. Furthermore, a high Li2O content can increase raw material costs and the dielectric constant (ε) rThis may cause an increase in the dielectric loss tangent (tanδ). Therefore, the Li2O content is preferably 10% or less, more preferably 9.0% or less, even more preferably 8.0% or less, particularly preferably 7.5% or less, and most preferably 7.0% or less.

[0068] Na2O is an optional component of the glass plate in this embodiment. The Na2O content is 0.0% or more and 10% or less. By including Na2O, the viscosity of the glass is reduced, which improves the moldability of vehicle window glass and architectural window glass. When Na2O is included, 0.10% or more is preferred, 0.20% or more is more preferred, 0.30% or more is even more preferred, 0.40% or more is particularly preferred, and 0.50% or more is most preferred.

[0069] On the other hand, if there is too much Na2O, the relative permittivity (ε r This causes an increase in the dielectric loss tangent (tanδ). Therefore, the Na2O content is preferably 9.0% or less, more preferably 7.0% or less, even more preferably 5.0% or less, particularly preferably 4.0% or less, and most preferably 3.0% or less.

[0070] K2O is an optional component of the glass plate in this embodiment. The K2O content is 0.0% or more and 10% or less. By including K2O, the viscosity of the glass is reduced, which improves the moldability of vehicle window glass and architectural window glass. When K2O is included, 0.10% or more is preferred, 0.20% or more is more preferred, 0.30% or more is even more preferred, 0.40% or more is particularly preferred, and 0.50% or more is most preferred.

[0071] On the other hand, if the K2O content is too high, the relative permittivity (ε r This causes an increase in the dielectric loss tangent (tanδ). Therefore, the K2O content is preferably 9.0% or less, more preferably 7.0% or less, even more preferably 5.0% or less, particularly preferably 4.0% or less, and most preferably 3.0% or less.

[0072] R2O refers to the total content of Li2O, Na2O, and K2O. The R2O content is between 3.0% and 11%. If the R2O content of the glass plate in this embodiment is 11% or less, the formability of vehicle windows and architectural windows is improved while maintaining weather resistance and millimeter-wave radio wave transmission. The R2O content of the glass plate in this embodiment is preferably 10.5% or less, more preferably 10.0% or less, even more preferably 9.5% or less, particularly preferably 9.0% or less, and most preferably 8.5% or less.

[0073] Also, the temperature T2 and T during manufacturing. 12 From the viewpoint of reducing the heat, or to facilitate heating by direct current application to the molten glass, the R2O content in the glass plate of this embodiment is preferably 3.5% or more, more preferably 4.0% or more, even more preferably 4.5% or more, particularly preferably 5.0% or more, and most preferably 5.5% or more.

[0074] Fe2O3 is an essential component of the glass plate in this embodiment and is included to provide heat-shielding properties. The Fe2O3 content is 0.01% or more and 1.00% or less. The Fe2O3 content referred to here is the total amount of iron, including FeO, which is an oxide of divalent iron, and Fe2O3, which is an oxide of trivalent iron.

[0075] If the Fe2O3 content is less than 0.01%, the glass may not be usable for applications requiring heat shielding, and it may become necessary to use expensive raw materials with low iron content for the manufacture of the glass plate. Furthermore, if the Fe2O3 content is less than 0.01%, excessive heat radiation may reach the bottom of the melting furnace during glass melting, potentially putting a load on the melting furnace. The Fe2O3 content in the glass plate of this embodiment is preferably 0.05% or more, more preferably 0.10% or more, even more preferably 0.15% or more, and particularly preferably 0.17% or more.

[0076] On the other hand, if the Fe2O3 content is too high, heat transfer by radiation during manufacturing may be hindered, making it difficult to melt the raw material. Furthermore, if the Fe2O3 content is too high, the visible light transmittance may decrease, making it unsuitable for applications such as vehicle window glass. The Fe2O3 content is preferably 0.80% or less, more preferably 0.50% or less, even more preferably 0.40% or less, and particularly preferably 0.25% or less.

[0077] Furthermore, the amount of iron ions contained in the above Fe2O3 is 0.20 ≤ [Fe 2+ ] / ([Fe 2+ ]+[Fe 3+ It is preferable that the value ]) ≤ 0.70 is satisfied. This makes it possible to achieve visible light transmittance and near-infrared light transmittance suitable for vehicle windows and building windows.

[0078] Here, [Fe 2+ ], and [Fe 3+ ] refers to the Fe contained in the glass plate of this embodiment, respectively. 2+ , and Fe 3+ It means the amount of [Fe 2+ ] / ([Fe 2+ ]+[Fe 3+ ])" refers to the Fe in the glass plate of this embodiment. 2+ and Fe 3+ Fe relative to the total content 2+ This refers to the percentage of the content.

[0079] [Fe 2+ ] / ([Fe 2+ ]+[Fe 3+ ]) can be found using the following method. After decomposing the crushed glass at room temperature with a mixed acid of hydrofluoric acid and hydrochloric acid, a certain amount of the decomposition solution is taken into a plastic container, and hydroxylammonium chloride solution is added, and the Fe in the sample solution 3+ Fe 2+ Reduce to . Then, add 2,2'-dipyridyl solution and ammonium acetate buffer and Fe 2+The color is developed. The color developing solution is diluted to a constant volume with deionized water, and the absorbance at a wavelength of 522 nm is measured using a spectrophotometer. Then the concentration is calculated from the calibration curve prepared using the standard solution and Fe 2+ Determine the quantity. Fe in the sample solution 3+ Fe 2+ Because it is reduced to this Fe 2+ The amount is "[Fe 2+ ]+[Fe 3+ ] means ".

[0080] Next, the crushed glass was decomposed at room temperature with a mixed acid of hydrofluoric acid and hydrochloric acid. Then, a certain amount of the decomposition solution was taken into a plastic container, and 2,2'-dipyridyl solution and ammonium acetate buffer were quickly added to Fe 2+ Only the color develops. The color developing solution is diluted with deionized water to a constant volume, and the absorbance at a wavelength of 522 nm is measured using a spectrophotometer. Then the concentration is calculated from the calibration curve prepared using the standard solution and Fe 2+ Calculate the quantity. This Fe 2+ The amount is [Fe in the sample] 2+ It means ].

[0081] And the above-calculated [Fe 2+ ], and [Fe 2+ ]+[Fe 3+ ] to [Fe 2+ ] / ([Fe 2+ ]+[Fe 3+ Calculate ]).

[0082] RO represents the total content of MgO, CaO, SrO, and BaO. The RO content is between 2.0% and 20%. If the RO content of the glass plate in this embodiment is 20% or less, the relative permittivity (ε) is maintained while maintaining weather resistance. r ) and the increase in dielectric loss tangent (tanδ) can be suppressed. The RO content in the glass plate of this embodiment is preferably 19% or less, more preferably 18% or less, even more preferably 17% or less, even more preferably 16% or less, particularly preferably 15% or less, and most preferably 14% or less.

[0083] Also, the temperature T2 and T during manufacturing. 12 From the viewpoint of reducing or improving the formability of vehicle window glass and architectural window glass, the RO content in the glass plate of this embodiment is preferably 4.0% or more, more preferably 6.0% or more, particularly preferably 8.0% or more, and most preferably 10% or more.

[0084] In the glass plate of this embodiment, the glass viscosity is 10 2 The temperature T2 at which dPa·s is obtained is 1650°C or lower. A T2 of 1650°C or lower results in excellent solubility of the glass raw materials. As mentioned above, one method for lowering T2 to 1650°C or lower is to adjust the content of MgO and Li2O within a predetermined range. In the glass plate of this embodiment, T2 is preferably 1640°C or lower, more preferably 1630°C or lower, even more preferably 1620°C or lower, particularly preferably 1615°C or lower, and most preferably 1610°C or lower.

[0085] The lower limit of T2 is not particularly limited, but in order to maintain weather resistance and glass density, T2 is typically preferably 1400°C or higher, more preferably 1450°C or higher, and even more preferably 1500°C or higher.

[0086] In the glass plate of this embodiment, the glass viscosity is 10 12 Temperature T at which dPa·s occurs 12 The temperature is below 730°C. 12 Because the temperature is below 730°C, bending and forming can be done at low temperatures. 12 One method for keeping the temperature below 730°C is to adjust the content of CaO, MgO, and Li2O within a predetermined range. In the glass plate of this embodiment, T 12 The temperature is preferably 720°C or lower, more preferably 700°C or lower, even more preferably 680°C or lower, even more preferably 670°C or lower, even more preferably 650°C or lower, and even more preferably 630°C or lower.

[0087] Furthermore, from the viewpoint of the firing temperature of the black ceramic, which is an example of a light-shielding layer printed on the windshield, a temperature of 550°C or higher is preferred, 560°C or higher is more preferred, 570°C or higher is even more preferred, and 590°C or higher is particularly preferred.

[0088] Furthermore, by adjusting the composition of the glass plate in this embodiment, a low dielectric loss tangent (tanδ) can be achieved, resulting in reduced dielectric loss and high millimeter-wave radio wave transmittance. Similarly, by adjusting the composition of the glass plate in this embodiment, the relative permittivity (ε) can be reduced. r This can also be adjusted to suppress radio wave reflection at the interface with the interlayer, achieving high millimeter-wave radio wave transmittance.

[0089] The relative permittivity (ε) of the glass plate of the embodiment at a frequency of 10 GHz r The relative permittivity (ε) at a frequency of 10 GHz is 6.5 or less. r If the ratio is 6.5 or less, the relative permittivity (ε) with respect to the interlayer is 6.5 or less. r The difference between (ε) becomes smaller, and the reflection of radio waves at the interface with the interlayer can be suppressed. The relative permittivity (ε) of the glass plate of this embodiment at a frequency of 10 GHz r The relative permittivity (ε) of the glass plate of this embodiment at a frequency of 10 GHz is preferably 6.4 or less, more preferably 6.3 or less, even more preferably 6.2 or less, particularly preferably 6.1 or less, and most preferably 6.0 or less. r There is no particular lower limit for ), but for example, it is 4.5 or higher.

[0090] Furthermore, the dielectric loss tangent (tanδ) of the glass plate in this embodiment at a frequency of 10 GHz is 0.0090 or less. If the dielectric loss tangent (tanδ) at a frequency of 10 GHz is 0.0090 or less, the radio wave transmittance can be increased. The dielectric loss tangent (tanδ) of the glass plate in this embodiment at a frequency of 10 GHz is preferably 0.0089 or less, more preferably 0.0088 or less, even more preferably 0.0087 or less, particularly preferably 0.0086 or less, and most preferably 0.0085 or less. Also, there is no particular lower limit to the dielectric loss tangent (tanδ) of the glass plate in this embodiment at a frequency of 10 GHz, but for example, it is 0.0050 or more.

[0091] The relative permittivity (ε) of the glass plate of this embodiment at a frequency of 10 GHz r If the dielectric loss tangent (tanδ) and the dielectric loss tangent (tanδ) satisfy the above range, the transmission rate of millimeter-wave radio waves can be increased even at frequencies of 10 GHz to 90 GHz.

[0092] The relative permittivity (ε) of the glass plate of this embodiment at a frequency of 10 GHz r The dielectric constant (%) and dielectric loss tangent (tanδ) can be measured, for example, by the split-post dielectric resonator method (SPDR method). For such measurements, a QWED 10 GHz nominal fundamental frequency type split-post dielectric resonator, a Keysight E8361C vector network analyzer, and Keysight 85071E option 300 dielectric constant calculation software can be used.

[0093] The average thermal expansion coefficient of the glass plate in this embodiment at 50°C to 350°C is 40 × 10 -7 A temperature of 40 × 10 is preferable. The glass plate of this embodiment has an average thermal expansion coefficient of 40 × 10 -7 A temperature of 1 / K or higher results in good bending properties at low temperatures. This can be achieved by having an R2O content of 3.0% or more and an RO content of 2.0% or more.

[0094] The average thermal expansion coefficient of the glass plate in this embodiment at 50°C to 350°C is 45 × 10⁻⁶. -7 / K or higher is more preferable, 50×10 -7 / K or higher is even more preferable, 55×10 -7 A value of 1 / K or higher is particularly preferred. On the other hand, if the average coefficient of thermal expansion of the glass plate in this embodiment becomes too large, thermal stress due to the temperature distribution of the glass plate is likely to occur during the glass plate molding process, the slow cooling process, or the molding process for vehicle windows or building windows, which may cause thermal cracking of the glass plate.

[0095] In addition, if the average thermal expansion coefficient of the glass plate of this embodiment becomes too large, the expansion difference between the glass plate and the support member or the like will increase, which may cause distortion and the glass plate may crack. The average thermal expansion coefficient of the glass plate of this embodiment at 50°C to 350°C should be 70×10 -7 / K or less, preferably 68×10 -7 / K or less, more preferably 65×10 -7 / K or less, and even more preferably 60×10 -7 / K or less.

[0096] The density of the glass plate of this embodiment may be 2.2 g / cm 3 or more and 2.6 g / cm 3 or less. Also, the Young's modulus of the glass plate of this embodiment may be 60 GPa or more and 90 GPa or less. If the glass plate of this embodiment satisfies these conditions, it can be suitably used as a window glass for vehicles, a window glass for buildings, or the like.

[0097] The glass plate of this embodiment preferably contains a certain amount or more of SiO2 to ensure weather resistance. As a result, the density of the glass plate of this embodiment can be 2.2 g / cm 3 or more. The density of the glass plate of this embodiment is preferably 2.3 g / cm 3 or more. When the density is 2.2 g / cm 3 or more, the sound insulation in the room and the vehicle interior is improved.

[0098] Also, when the density of the glass plate of this embodiment is 2.6 g / cm 3 or less, it is less likely to become brittle and high sound insulation can be maintained. The density of the glass plate of this embodiment is preferably 2.5 g / cm 3 or less.

[0099] The glass plate of this embodiment has high rigidity due to its high Young's modulus, making it more suitable for vehicle windows and the like. The Young's modulus of the glass plate of this embodiment is preferably 65 GPa or higher, more preferably 70 GPa or higher, even more preferably 72 GPa or higher, still more preferably 74 GPa or higher, still more preferably 75 GPa or higher, particularly preferably 77 GPa or higher, and most preferably 80 GPa or higher.

[0100] On the other hand, increasing the amount of Al2O3 or MgO to raise Young's modulus will increase the relative permittivity of the glass (ε r Because the dielectric loss tangent (tanδ) increases, the transmittance of millimeter-wave radio waves may decrease. For this reason, the glass plate of this embodiment is better prepared by adjusting the content of Al2O3 and MgO, and an appropriate Young's modulus is 90 GPa or less, more preferably 88 GPa or less, and even more preferably 86 GPa or less.

[0101] Furthermore, the glass plate of this embodiment is T g The temperature is preferably 450°C or higher and 600°C or lower. In this specification, T g This represents the glass transition point of glass. g If the temperature is within this predetermined range, the glass can be bent under normal manufacturing conditions. The T of the glass plate in this embodiment g If the temperature is lower than 450°C, there will be no problems with moldability, but the alkali content or alkaline earth content will become too high, which can lead to problems such as low millimeter-wave radio wave transmittance, excessive thermal expansion of the glass, and reduced weather resistance. Also, the T of the glass plate in this embodiment g If the temperature is lower than 450°C, the glass may devitrify in the molding temperature range, making molding impossible.

[0102] T of the glass plate in this embodiment g A temperature of 470°C or higher is more preferable, 490°C or higher is even more preferable, and 510°C or higher is particularly preferable.

[0103] Meanwhile, T gIf the temperature is too high, it will reduce productivity due to high-temperature control during glass bending, therefore, the T of the glass plate in this embodiment g A temperature of 590°C or lower is more preferable, 580°C or lower is even more preferable, and 570°C or lower is particularly preferable.

[0104] The glass plate of this embodiment may contain components other than SiO2, Al2O3, B2O3, MgO, CaO, SrO, BaO, ZnO, Li2O, Na2O, K2O, and Fe2O3 (hereinafter also referred to as "other components"), and if so, the total content of such components is preferably 5.0% or less.

[0105] Other components include, for example, P2O 5、 Examples include ZrO2, Y2O3, TiO2, CeO2, Nd2O5, GaO2, GeO2, MnO2, CoO, Cr2O3, V2O5, Se, Au2O3, Ag2O, CuO, CdO, SO3, Cl, F, SnO2, Sb2O3, and NiO. These can be metal ions or oxides.

[0106] Other components may be included in amounts of 5.0% or less for various purposes (e.g., clarification and coloring). If the total content of other components exceeds 5.0%, it may reduce the millimeter-wave radio wave transmittance. The total content of other components is preferably 2.0% or less, more preferably 1.0% or less, even more preferably 0.50% or less, particularly preferably 0.30% or less, and most preferably 0.10% or less. In addition, to prevent environmental impact, the content of As2O3 and PbO is preferably less than 0.0010% each.

[0107] The glass plate of this embodiment may contain P2O5. The P2O5 content may be 0.0% or more and 10% or less. P2O5 has the function of reducing the viscosity of the glass. When P2O5 is included in the glass plate of this embodiment, 0.2% or more is preferred, 0.5% or more is more preferred, 0.8% or more is even more preferred, and 1.0% or more is particularly preferred.

[0108] On the other hand, when the glass plate of this embodiment is manufactured by the float process, P2O5 tends to cause defects in the glass within the float bath. Therefore, the P2O5 content in the glass plate of this embodiment is preferably 5.0% or less, more preferably 4.0% or less, even more preferably 3.0% or less, and particularly preferably 2.0% or less.

[0109] The glass plate of this embodiment may contain Cr2O3. Cr2O3 acts as an oxidizing agent to control the amount of FeO. When the glass plate of this embodiment contains Cr2O3, its content is preferably 0.0020% or more, and more preferably 0.0040% or more.

[0110] Since Cr2O3 has a coloration to visible light, there is a risk of a decrease in visible light transmittance. Therefore, when the glass plate of this embodiment contains Cr2O3, the amount is preferably 1.0% or less, more preferably 0.50% or less, even more preferably 0.30% or less, and particularly preferably 0.10% or less.

[0111] The glass plate of this embodiment may contain SnO2. SnO2 acts as a reducing agent to control the amount of FeO. When the glass plate of this embodiment contains SnO2, its content is preferably 0.010% or more, more preferably 0.040% or more, even more preferably 0.060% or more, and particularly preferably 0.080% or more.

[0112] On the other hand, in order to suppress defects caused by SnO2 during the manufacturing of glass plates, the SnO2 content in the glass plates of this embodiment is preferably 1.0% or less, more preferably 0.50% or less, even more preferably 0.30% or less, and particularly preferably 0.20% or less.

[0113] The glass plate of this embodiment may contain NiO, but the inclusion of NiO may lead to glass fracture due to the formation of NiS. Therefore, the NiO content is preferably 0.010% or less, more preferably 0.0050% or less, and even more preferably substantially NiO-free.

[0114] The glass plate of this embodiment may contain TiO2. Since TiO2 absorbs in the ultraviolet region, it can reduce the ultraviolet transmittance (Tuv) and improve UV-cutting performance. When the glass plate of this embodiment contains TiO2, its content is preferably 0.010% or more, more preferably 0.040% or more, even more preferably 0.075% or more, and particularly preferably 0.15% or more. Since TiO2 has a coloration effect on visible light, the transmittance in the visible region may decrease. When the glass plate of this embodiment contains TiO2, its content is preferably 0.80% or less, more preferably 0.50% or less, even more preferably 0.40% or less, and particularly preferably 0.30% or less.

[0115] The glass plate of this embodiment may contain CeO2. Since CeO2 absorbs in the ultraviolet region, it can reduce the ultraviolet transmittance (Tuv) and improve UV-cutting performance. When the glass plate of this embodiment contains CeO2, its content is preferably 0.010% or more, more preferably 0.020% or more, even more preferably 0.040% or more, and particularly preferably 0.070% or more. CeO2 absorbs light in the ultraviolet region, which can cause solarization and reduce the transmittance in the visible region. When the glass plate of this embodiment contains CeO2, its content is preferably 0.25% or less, more preferably 0.18% or less, even more preferably 0.14% or less, and particularly preferably 0.10% or less.

[0116] The glass plate of this embodiment preferably has sufficient visible light transmittance. When converted to a thickness of 2.00 mm, the visible light transmittance Tv, as defined in ISO-9050:2003 using a D65 light source, is preferably 75% or higher. Tv is preferably 77% or higher, and more preferably 80% or higher. Also, Tv is, for example, 90% or lower.

[0117] Furthermore, the glass plate of this embodiment preferably has high heat-shielding properties. When converted to a thickness of 2.00 mm, the total solar radiation transmittance Tts, as defined in ISO-13837:2008 convention A and measured at a wind speed of 4 m / s, is preferably 88% or less. Tts is preferably 80% or less, and more preferably 78% or less. Also, Tts is, for example, 70% or more.

[0118] Furthermore, the glass plate of this embodiment preferably has low ultraviolet transmittance, and when converted to a thickness of 2.00 mm, the ultraviolet transmittance Tuv as defined by ISO-9845A is preferably 80% or less. Tuv is more preferably 70% or less, even more preferably 60% or less, and particularly preferably 50% or less. Also, Tuv is, for example, 10% or more.

[0119] Furthermore, when the glass plate of this embodiment is converted to a thickness of 2.00 mm, it is defined in JIS Z 8781-4 when using a D65 light source. * -5.0 or higher is preferred, -3.0 or higher is more preferred, and -2.0 or higher is even more preferred. Also, a * It is preferably 2.0 or less, more preferably 1.0 or less, and even more preferably 0 or less.

[0120] Furthermore, when the glass plate of this embodiment is converted to a thickness of 2.00 mm, it meets the requirements of JIS Z 8781-4 when using a D65 light source. * -5.0 or higher is preferred, -3.0 or higher is more preferred, and -1.0 or higher is even more preferred. Also, b * The ratio is preferably 5.0 or less, more preferably 4.0 or less, and even more preferably 3.0 or less. The glass plate of this embodiment is a * and b * Because it falls within the above range, it offers superior design appeal as architectural window glass and vehicle window glass.

[0121] The method for manufacturing the glass plate in this embodiment is not particularly limited, but for example, a glass plate formed by the known float method is preferred. In the float method, a molten glass base is floated on a molten metal such as tin, and a glass plate with uniform thickness and width is formed by precise temperature control. Alternatively, a glass plate formed by the known roll-out method or down-draw method may also be used, and the surface may be polished to produce a glass plate with uniform thickness. The down-draw method is broadly classified into the slot down-draw method and the overflow down-draw method (fusion method), but both are methods in which molten glass is continuously flowed down from a molded body to form a strip-shaped glass ribbon.

[0122] The glass plate in this embodiment may be air-cooled strengthened. Air-cooled strengthened glass is a glass plate that has been heat-strengthened. Heat strengthening involves rapidly cooling a uniformly heated glass plate from a temperature near its softening point, generating compressive stress on the glass surface due to the temperature difference between the glass surface and the interior of the glass. The compressive stress is generated uniformly across the entire surface of the glass, forming a compressive stress layer of uniform depth across the entire surface of the glass. Heat strengthening is more suitable for strengthening thick glass plates than chemical strengthening.

[0123] Normally, glass with low alkali content or no alkali at all has a small average coefficient of thermal expansion, making it difficult to temper with air cooling. However, the glass plate of this embodiment has a larger average coefficient of thermal expansion than conventional glass plates with low alkali content or no alkali at all, making it suitable for tempering with air cooling.

[0124] [Laminated glass] The laminated glass according to an embodiment of the present invention comprises a first glass plate, a second glass plate, and an interlayer sandwiched between the first glass plate and the second glass plate, wherein at least one of the first glass plate and the second glass plate is the glass plate described above.

[0125] Figure 1 shows an example of laminated glass 10 according to this embodiment. The laminated glass 10 comprises a first glass plate 11, a second glass plate 12, and an interlayer 13 sandwiched between the first glass plate 11 and the second glass plate 12.

[0126] The laminated glass 10 according to this embodiment is not limited to the configuration shown in Figure 1, and can be modified without departing from the spirit of the present invention. For example, the interlayer 13 may be formed as a single layer as shown in Figure 1, or as two or more layers. Furthermore, the laminated glass 10 according to this embodiment may have three or more glass plates, in which case an organic resin or the like may be interposed between adjacent glass plates.

[0127] Hereinafter, the laminated glass 10 according to this embodiment will be described as having only two glass plates, a first glass plate 11 and a second glass plate 12, with an interlayer 13 sandwiched between them.

[0128] In the laminated glass of this embodiment, from the viewpoint of radio wave transparency and bendability, it is preferable to use the above-mentioned glass plates for both the first glass plate 11 and the second glass plate 12. In this case, the first glass plate 11 and the second glass plate 12 may both be glass plates of the same composition, or they may be glass plates of different compositions.

[0129] If one of the first glass plate 11 and the second glass plate 12 is not the type of glass plate described above, the type of glass plate is not particularly limited, and conventionally known glass plates used for vehicle windows and the like can be used. Specifically, examples include alkali aluminosilicate glass and soda-lime glass. These glass plates may or may not be colored, as long as their transparency is not impaired.

[0130] Furthermore, in the laminated glass of this embodiment, one of the first glass plate 11 and the second glass plate 12 may be alkali aluminosilicate glass containing 1.0% or more Al2O3. By using the above-mentioned alkali aluminosilicate glass for either the first glass plate 11 or the second glass plate 12, chemical strengthening becomes possible, as described later, and the strength can be increased.

[0131] From the viewpoint of weather resistance and chemical strengthening, the above alkali aluminosilicate glass preferably has an Al2O3 content of 2.0% or more, more preferably 2.5% or more, even more preferably 10% or more, particularly preferably 12% or more, and most preferably 13% or more.

[0132] Furthermore, in alkali aluminosilicate glass, a high Al2O3 content may reduce the millimeter-wave radio wave transmittance. Therefore, the Al2O3 content should be 25% or less, preferably 20% or less, more preferably 19% or less, and even more preferably 15% or less.

[0133] The alkali aluminosilicate glass mentioned above can be exemplified by the following compositions. Each component is expressed in mole percentage based on the oxide. 61% ≤ SiO2 ≤ 77% 1.0% ≤ Al2O3 ≤ 25% 0.0% ≤ B2O3 ≤ 10% 0.0% ≤ MgO ≤ 15% 0.0% ≤ CaO ≤ 10% 0.0% ≤ SrO ≤ 1.0% 0.0% ≤ BaO ≤ 1.0% 0.0% ≤ Li2O ≤ 15% 2.0% ≤ Na2O ≤ 15% 0.0% ≤ K2O ≤ 6.0% 0.0% ≤ ZrO2 ≤ 4.0% 0.0% ≤ TiO2 ≤ 1.0% 0.0% ≤ Y2O3 ≤ 2.0% 10% ≤ R2O ≤ 25% 0.0% ≤ RO ≤ 20% (R2O represents the total amount of Li2O, Na2O, and K2O, while RO represents the total amount of MgO, CaO, SrO, and BaO.)

[0134] Furthermore, in the laminated glass of this embodiment, one of the first glass plate 11 and the second glass plate 12 may be soda-lime glass. The soda-lime glass may be soda-lime glass containing less than 1.0% Al2O3. Specifically, the following glass compositions can be exemplified. 60% ≤ SiO2 ≤ 75% 0.0% ≤ Al2O3 < 1.0% 2.0% ≤ MgO ≤ 11% 2.0% ≤ CaO ≤ 10% 0.0% ≤ SrO ≤ 3.0% 0.0% ≤ BaO ≤ 3.0% 10% ≤ Na2O ≤ 18% 0.0% ≤ K2O ≤ 8.0% 0.0% ≤ ZrO2 ≤ 4.0% 0.0010% ≤ Fe2O3 ≤ 5.0%

[0135] The thickness of the first glass plate 11 or the second glass plate 12 is preferably 0.50 mm or more, more preferably 0.70 mm or more, even more preferably 1.00 mm or more, particularly preferably 1.20 mm or more, and most preferably 1.50 mm or more. A thickness of 0.50 mm or more for the first glass plate 11 or the second glass plate 12 is preferable from the viewpoint of impact resistance.

[0136] Furthermore, the thickness of the first glass plate 11 or the second glass plate 12 is preferably 3.70 mm or less, more preferably 3.50 mm or less, even more preferably 3.20 mm or less, even more preferably 3.00 mm or less, particularly preferably 2.50 mm or less, and most preferably 2.30 mm or less. When the thickness of the first glass plate 11 or the second glass plate 12 is 3.70 mm or less, the weight of the laminated glass 10 does not become too large, which is preferable in terms of improving fuel efficiency when used in a vehicle.

[0137] Furthermore, the thicknesses of the first glass plate 11 and the second glass plate 12 may be the same or different.

[0138] In the laminated glass 10 of this embodiment, the total thickness of the first glass plate 11, the second glass plate 12, and the interlayer 13 is preferably 2.30 mm or more. Sufficient strength can be obtained with a total thickness of 2.30 mm or more. The total thickness is more preferably 2.50 mm or more, even more preferably 2.70 mm or more, even more preferably 3.00 mm or more, particularly preferably 3.50 mm or more, and most preferably 4.00 mm or more.

[0139] Furthermore, from the viewpoint of improving radio wave transparency and reducing weight, the total thickness is preferably 6.00 mm or less, more preferably 5.80 mm or less, even more preferably 5.50 mm or less, and particularly preferably 5.30 mm or less.

[0140] In the laminated glass 10 of this embodiment, the thickness of the first glass plate 11 and the second glass plate 12 may be constant throughout the entire surface, or it may vary from place to place as needed, such as by forming a wedge shape in which the thickness of one or both of the first glass plate 11 and the second glass plate 12 gradually decreases.

[0141] One of the first glass plate 11 and the second glass plate 12 may be a chemically strengthened glass that has been glass-strengthened to improve its strength. A method for chemical strengthening is, for example, ion exchange. In ion exchange, the glass plate is immersed in a treatment solution (e.g., potassium nitrate molten salt) and compressed stress is generated on the glass surface by exchanging ions with small ionic radii (e.g., Na ions) for ions with large ionic radii (e.g., K ions). The compressed stress is generated uniformly across the entire surface of the glass plate, forming a compressive stress layer of uniform depth across the entire surface of the glass plate.

[0142] The magnitude of the compressive stress on the surface of the glass plate (hereinafter also referred to as surface compressive stress CS) and the depth DOL of the compressive stress layer formed on the surface of the glass plate can be adjusted by the glass composition, chemical strengthening treatment time, and chemical strengthening treatment temperature, respectively. Chemically strengthened glass can be obtained by chemically strengthening the alkali aluminosilicate glass described above.

[0143] The shape of the first glass plate 11 and the second glass plate 12 may be flat, or it may be curved with curvature in all or part of its surface. If the first glass plate 11 and the second glass plate 12 are curved, they may be a single-bend shape curving in only one direction, either vertically or horizontally, or a double-bend shape curving in both vertically or horizontally. If the first glass plate 11 and the second glass plate 12 are double-bend shapes, the radii of curvature in the vertical and horizontal directions may be the same or different. If the first glass plate 11 and the second glass plate 12 are curved, the radii of curvature in the vertical and / or horizontal directions are preferably 1000 mm or more. The shape of the main surface of the first glass plate 11 and the second glass plate 12 is such that it fits the window opening of the vehicle in which it is installed.

[0144] The interlayer 13 in this embodiment is sandwiched between the first glass plate 11 and the second glass plate 12. By including the interlayer 13, the laminated glass 10 of this embodiment firmly bonds the first glass plate 11 and the second glass plate 12 and can mitigate the impact force when flying fragments collide with the glass plate.

[0145] As the interlayer 13, various organic resins commonly used in laminated glass for conventional vehicles can be used. For example, polyethylene (PE), ethylene vinyl acetate copolymer (EVA), polypropylene (PP), polystyrene (PS), methacrylic resin (PMA), polyvinyl chloride (PVC), polyethylene terephthalate (PET), polybutylene terephthalate (PBT), cellulose acetate (CA), diallyl phthalate resin (DAP), urea resin (UP), melamine resin (MF), unsaturated polyester (UP), polyvinyl butyral (PVB), polyvinyl formal ( Materials such as PVF, polyvinyl alcohol (PVAL), vinyl acetate resin (PVAc), ionomer (IO), polymethylpentene (TPX), vinylidene chloride (PVDC), polysulfone (PSF), polyvinylidene fluoride (PVDF), methacrylic styrene copolymer resin (MS), polyalate (PAR), polyallyl sulfone (PASF), polybutadiene (BR), polyethersulfone (PESF), or polyetheretherketone (PEEK) can be used. Among these, EVA and PVB are preferred from the viewpoint of transparency and adhesion, and PVB is particularly preferred because it can provide sound insulation.

[0146] The thickness of the interlayer 13 is preferably 0.30 mm or more, more preferably 0.50 mm or more, and even more preferably 0.70 mm or more, from the viewpoint of impact force mitigation and sound insulation.

[0147] Furthermore, the thickness of the interlayer 13 is preferably 1.00 mm or less, more preferably 0.90 mm or less, and even more preferably 0.80 mm or less, from the viewpoint of suppressing a decrease in visible light transmittance. In addition, the thickness of the interlayer 13 is preferably in the range of 0.30 mm to 1.00 mm, and more preferably in the range of 0.70 mm to 0.80 mm.

[0148] The interlayer 13 may have a uniform thickness across the entire surface, or its thickness may vary from place to place as needed.

[0149] Furthermore, if the difference in the coefficient of linear expansion between the interlayer 13 and the first glass plate 11 or the second glass plate 12 is large, cracks or warping may occur in the laminated glass 10 when it is manufactured through the heating process described later, potentially causing a defect in appearance. Therefore, it is preferable that the difference between the coefficient of linear expansion between the interlayer 13 and the first glass plate 11 or the second glass plate 12 be as small as possible. The difference between the coefficient of linear expansion between the interlayer 13 and the first glass plate 11 or the second glass plate 12 may be expressed as the difference between the average thermal expansion coefficients in a predetermined temperature range. In particular, since the resin constituting the interlayer 13 has a low glass transition temperature, the predetermined difference in average thermal expansion coefficients may be set in a temperature range below the glass transition temperature of the resin material. Furthermore, the difference in the coefficient of linear expansion between the first glass plate 11 or the second glass plate 12 and the resin material may be set by a predetermined temperature below the glass transition temperature of the resin material.

[0150] Furthermore, the interlayer 13 may also be an adhesive layer containing an adhesive, and the adhesive is not particularly limited, but for example, an acrylic adhesive or a silicone adhesive can be used.

[0151] When the interlayer 13 is an adhesive layer, there is no need to go through a heating process in the bonding process between the first glass plate 11 and the second glass plate 12, so there is less risk of the above-mentioned cracking or warping occurring.

[0152] [Other layers] The laminated glass 10 of this embodiment may include layers other than the first glass plate 11, the second glass plate 12, and the interlayer 13 (hereinafter also referred to as "other layers"), to the extent that they do not impair the effects of the present invention. For example, it may include a coating layer that provides water-repellent, hydrophilic, or anti-fogging functions, or an infrared reflective film. The position of the other layers is not particularly limited and may be provided on the surface of the laminated glass 10, or it may be provided so as to be sandwiched between the first glass plate 11, the second glass plate 12, or the interlayer 13. Furthermore, the laminated glass 10 of this embodiment may include a black ceramic layer or the like that is arranged in a strip shape on part or all of the peripheral edge for the purpose of concealing mounting parts to frames, wiring conductors, etc.

[0153] The manufacturing method for the laminated glass 10 according to the embodiment of the present invention can be the same as that for conventionally known laminated glass. For example, by stacking a first glass plate 11, an interlayer 13, and a second glass plate 12 in this order, and then going through the steps of heating and pressurizing, a laminated glass 10 can be obtained in which the first glass plate 11 and the second glass plate 12 are joined via the interlayer 13.

[0154] The manufacturing method for the laminated glass 10 according to an embodiment of the present invention may involve, for example, a step of heating and shaping the first glass plate 11 and the second glass plate 12, followed by a step of inserting the interlayer 13 between the first glass plate 11 and the second glass plate 12, and then heating and pressurizing the interlayer. By going through such a process, the laminated glass 10 may be configured such that the first glass plate 11 and the second glass plate 12 are joined via the interlayer 13.

[0155] In the embodiment of the present invention, the laminated glass 10 has a total thickness of 6.00 mm or less for the first glass plate 11, the second glass plate 12, and the interlayer 13, and preferably the visible light transmittance Tv, as defined in ISO-9050:2003 using a D65 light source, is 70% or more. Tv is more preferably 71% or more, and even more preferably 72% or more. Also, Tv is, for example, 90% or less.

[0156] In the laminated glass 10 according to the embodiment of the present invention, the total thickness of the first glass plate 11, the second glass plate 12, and the interlayer 13 is 6.00 mm or less, and the total solar radiation transmittance Tts, as defined in ISO-13837:2008 convention A and measured at a wind speed of 4 m / s, is preferably 80% or less. A total solar radiation transmittance Tts of 80% or less in the laminated glass 10 according to the embodiment of the present invention provides sufficient heat shielding. A Tts of 75% or less is more preferable, 70% or less is even more preferable, and 68% or less is particularly preferable. Also, Tts can be, for example, 55% or more.

[0157] In the laminated glass 10 according to the embodiment of the present invention, the total thickness of the first glass plate 11, the second glass plate 12, and the interlayer 13 is 6.00 mm or less, and the ultraviolet transmittance Tuv, as defined by ISO-9845A, is preferably 3.0% or less. A Tuv of 3.0% or less in the laminated glass 10 according to the embodiment of the present invention is sufficient to block the transmission of ultraviolet rays. A Tuv of 2.8% or less is more preferable, 2.6% or less is even more preferable, and 2.5% or less is particularly preferable. Furthermore, a Tuv of, for example, 0.10% or more is also preferable.

[0158] In the laminated glass 10 according to the embodiment of the present invention, the total thickness of the first glass plate 11, the second glass plate 12, and the interlayer 13 is 6.00 mm or less, and the maximum value of the radio wave transmission loss S21 when radio waves with a frequency of 75 GHz to 80 GHz are incident on the first glass plate 11 at an incident angle of 60° is preferably -4.0 dB or more. The maximum value of the radio wave transmission loss S21 under the above conditions is preferably -3.0 dB or more, and more preferably -2.5 dB or more. Furthermore, the maximum value of the radio wave transmission loss S21 under the above conditions is, for example, -0.50 dB or less.

[0159] Here, the radio wave transmission loss S21 is the relative permittivity (ε) of each material used in laminated glass. r This refers to the insertion loss derived based on the dielectric loss tangent (tanδ) (where δ is the loss angle), and the smaller the absolute value of the radio wave transmission loss S21, the higher the radio wave transmission.

[0160] Furthermore, the angle of incidence refers to the angle between the normal to the main surface of the laminated glass 10 and the direction of incidence of the radio waves.

[0161] In the laminated glass 10 according to the embodiment of the present invention, the total thickness of the first glass plate 11, the second glass plate 12, and the interlayer 13 is 6.00 mm or less, and the maximum value of the radio wave transmission loss S21 when radio waves with a frequency of 75 GHz to 80 GHz are incident on the first glass plate 11 at an incident angle of 45° is preferably -4.0 dB or more. The maximum value of the radio wave transmission loss S21 under the above conditions is preferably -3.0 dB or more, and more preferably -2.5 dB or more. Furthermore, the maximum value of the radio wave transmission loss S21 under the above conditions is, for example, -0.50 dB or less.

[0162] In the laminated glass 10 according to the embodiment of the present invention, the total thickness of the first glass plate 11, the second glass plate 12, and the interlayer 13 is 6.00 mm or less, and the maximum value of the radio wave transmission loss S21 when radio waves with a frequency of 75 GHz to 80 GHz are incident on the first glass plate 11 at an incident angle of 20° is preferably -4.0 dB or more. The maximum value of the radio wave transmission loss S21 under the above conditions is preferably -3.0 dB or more, and more preferably -2.5 dB or more. Furthermore, the maximum value of the radio wave transmission loss S21 under the above conditions is, for example, -0.50 dB or less.

[0163] The laminated glass 10 according to an embodiment of the present invention has a total thickness of 6.00 mm or less for the first glass plate 11, the second glass plate 12, and the interlayer 13, and uses a D65 light source and has a chromaticity a as defined in JIS Z 8781-4. * -8.0 or higher is preferred, -7.0 or higher is more preferred, -6.0 or higher is even more preferred, and -5.5 or higher is particularly preferred. Also, a * It is preferably 2.0 or less, more preferably 1.0 or less, and even more preferably 0 or less.

[0164] Furthermore, the total thickness of the first glass plate 11, the second glass plate 12, and the interlayer 13 is 6.00 mm or less, and the chromaticity b as defined in JIS Z 8781-4 is measured using a D65 light source. * -5.0 or higher is preferred, -3.0 or higher is more preferred, and -1.0 or higher is even more preferred. Also, b * The ratio is preferably 7.0 or less, more preferably 5.0 or less, and even more preferably 4.0 or less. The glass plate of this embodiment is a* and b * Because it falls within the above range, it offers superior design qualities for architectural and vehicle window glass.

[0165] [Vehicle window glass, building window glass] The vehicle window glass and building window glass of this embodiment have the above-mentioned glass plate. Alternatively, the building window glass and vehicle window glass of this embodiment may be made of the above-mentioned laminated glass.

[0166] The following describes an example of using the laminated glass 10 of this embodiment as a vehicle window glass, with reference to the drawings.

[0167] Figure 2 is a conceptual diagram showing the laminated glass 10 of this embodiment being installed in an opening 110 formed at the front of the vehicle 100 and used as a vehicle window. The laminated glass 10 used as a vehicle window may have a housing (case) 120 containing information devices, etc., attached to its inner surface to ensure the vehicle's driving safety.

[0168] Furthermore, the information devices housed within the housing are devices that use cameras, radar, etc., to prevent rear-end collisions and impacts with vehicles, pedestrians, obstacles, etc., in front of the vehicle, and to warn the driver of danger. Examples include information receiving devices and / or information transmitting devices, which include millimeter-wave radar, stereo cameras, infrared lasers, etc., and perform signal transmission and reception. The "signals" refer to electromagnetic waves, including millimeter waves, visible light, infrared light, etc.

[0169] Figure 3 is an enlarged view of portion S in Figure 2, and is a perspective view showing the portion where the housing 120 is attached to the laminated glass 10 of this embodiment. The housing 120 houses a millimeter-wave radar 201 and a stereo camera 202 as information devices. The housing 120, which houses the information devices, is usually mounted on the outside of the vehicle from the rearview mirror 150 and on the inside of the vehicle from the laminated glass 10, but it may be mounted on other parts as well.

[0170] Figure 4 is a cross-sectional view taken in a direction perpendicular to the horizontal line, including the YY line in Figure 3. In the laminated glass 10, the first glass plate 11 is positioned on the outside of the vehicle. As described above, the angle of incidence θ of the radio waves 300 used for communication of information devices such as millimeter-wave radar 201 to the main surface of the first glass plate 11 can be evaluated as, for example, 20°, 45°, 60°, etc. [Examples]

[0171] The present invention will be specifically described below with reference to examples, but the present invention is not limited thereto.

[0172] <Preparation of glass plates for Examples 1 to 11> The raw materials were placed in a platinum crucible and melted at 1650°C for 3 hours to obtain molten glass with the glass composition (unit: mol%) shown in Table 1. The molten glass was poured onto a carbon plate and slowly cooled. Both sides of the resulting plate-like glass were polished to obtain a glass plate with a thickness of 2.00 mm. Examples 1 to 3 are comparative examples, and Examples 4 to 11 are examples.

[0173] The method for determining the values ​​shown in Table 1 is described below. (1) Glass transition temperature (Tg): The values ​​were measured using TMA and determined according to the JIS R3103-3 standard (2001).

[0174] (2) Average thermal expansion coefficient (CTE(50-350)) between 50°C and 350°C: The values ​​were measured using a differential thermal expander (TMA) and determined according to the JIS R3102 standard (1995 edition).

[0175] (3) Viscosity: Using a rotational viscometer, the viscosity η is 10 2 The temperature T2 (reference temperature for solubility) at which the viscosity η becomes dPa·s was measured. 12 Temperature T when the temperature is dPa·s 12 The reference temperature for bendability was measured using the beam bending method.

[0176] (4) Density: A 20g glass block, free of bubbles and cut from a glass plate, was measured using the Archimedes method.

[0177] (5) Young's modulus: Measurements were taken at 25°C using the ultrasonic pulse method (Olympus, DL35).

[0178] (6) Specific permittivity (ε r ), dielectric loss tangent (tanδ): Using the Split Post Dielectric Resonator (SPDR) method manufactured by QWED, the relative permittivity (ε) of a frequency of 10 GHz was measured under conditions of slow cooling at 1°C / min. r The dielectric loss tangent (tanδ) was measured.

[0179] (7) Visible light transmittance (Tv): The Tv, converted to a thickness of 2.00 mm, was measured using a D65 light source according to the method defined in ISO-9050:2003. The Tv was measured using a Perkinelmer LAMBDA950 spectrophotometer.

[0180] (8) Total solar radiation transmittance (Tts): The Tts (thickness tang) was obtained by converting the thickness to 2.00 mm, using the method defined in ISO-13837:2008 convention A, measured at a wind speed of 4 m / s. The Tts was measured using a Perkinelmer LAMBDA950 spectrophotometer.

[0181] (9) Ultraviolet transmittance (Tuv): The Tuv value, converted to a thickness of 2.00 mm, was measured according to the method specified in ISO-9845A. The Tuv value was measured using a Perkinelmer LAMBDA950 spectrophotometer.

[0182] (10) Chromaticity (a * ,b * ): Chromaticity a as defined in JIS Z 8781-4 using a D65 light source * ,b *We measured it.

[0183] The measurement results are shown in Table 1.

[0184] [Table 1]

[0185] The glass plates in Examples 4 to 11, which correspond to the embodiments, have a relative permittivity (ε) at a frequency of 10 GHz. r The viscosity η was 6.5 or less, and the dielectric loss tangent (tanδ) at a frequency of 10 GHz was 0.0090 or less, indicating good radio wave transmission. In addition, the viscosity η was 10 2 The temperature T2 at which the viscosity becomes dPa·s is 1650°C or lower, and the viscosity η is 10 12 Temperature T at which dPa·s occurs 12 It was found that the temperature is below 730°C, and that the melting temperature and bending / forming temperature are low, resulting in excellent processability.

[0186] On the other hand, the glass plate in Example 1, which corresponds to the comparative example, has a high R2O content, so the relative permittivity at a frequency of 10 GHz is (ε r The coefficient of error () exceeded 6.5, and the dielectric loss tangent (tanδ) at a frequency of 10 GHz exceeded 0.0090, indicating poor radio wave penetration.

[0187] Furthermore, the glass plate in Example 2, which corresponds to a comparative example, has a high Al2O3 content and R2O content of 3.0% or less, so its viscosity η is 10 12 Temperature T at which dPa·s occurs 12 The temperature exceeded 730°C, resulting in poor bendability.

[0188] Furthermore, since the glass plate in Example 3, which corresponds to a comparative example, does not contain MgO or Li2O, its viscosity η is 10 2 The temperature T2 at which dPa·s is obtained exceeds 1650°C, indicating poor solubility.

[0189] <Fabrication of laminated glass> Laminated glass products for Manufacturing Examples 1 to 14 were manufactured using the following procedure. Manufacturing Example 1 is a comparative example, and Manufacturing Examples 2 to 14 are examples.

[0190] (Manufacturing Example 1) As the first and second glass plates, glass plates (Example 1) with a thickness of 2.00 mm and the composition shown in Table 1 were used. A polyvinyl butyral with a thickness of 0.76 mm was used as the interlayer. The first glass plate, interlayer, and second glass plate were laminated in this order and subjected to a compression treatment using an autoclave (1 MPa, 130°C, 3 hours) to produce the laminated glass of Production Example 1. The total thickness of the laminated glass of Production Example 1, consisting of the first glass plate, second glass plate, and interlayer, was 4.76 mm.

[0191] (Manufacturing Examples 2-14) Except for the points shown in Table 2, the laminated glass of Manufacturing Examples 2 to 14 was manufactured in the same manner as Manufacturing Example 1.

[0192] [Optical properties] The visible light transmittance (Tv) was measured using a D65 light source in the same manner as described above, according to the method specified in ISO-9050:2003. Total solar radiation transmittance (Tts) was measured using the same method as described above, as defined in ISO-13837:2008 convention A, with a wind speed of 4 m / s. The ultraviolet transmittance (Tuv) was measured using the method specified in ISO-9845A, as described above. Also, chromaticity (a * ,b * Similarly to the above, chromaticity a as defined in JIS Z 8781-4 * , b * This was measured using a D65 light source. The results are shown in Table 2.

[0193] [Radio transparency] For the laminated glass of Manufacturing Examples 1 to 14, the radio wave transmission loss S21 when a TM wave with a frequency of 76 GHz, 77 GHz, 78 GHz, or 79 GHz is incident at an incident angle of 20°, 45°, or 60° is expressed as the relative permittivity (ε) of each material used. r The values ​​were calculated based on the dielectric loss tangent (tanδ). Specifically, antennas were placed facing each other, and each of the resulting laminated glass panels was installed between them so that the incident angle was between 0° and 60°. Then, for TM waves of frequencies 76GHz and 79GHz, the radio wave transmission loss S21 was measured at a 100mmΦ aperture, with the case without a radio wave transparent substrate being set to 0[dB], and the radio wave transparency was evaluated according to the following criteria.

[0194] <Evaluation of radio wave transparency> A: -1.5 [dB] ≤ S21 B: -2.0 [dB] ≤ S21 < -1.5 [dB] C: -2.5[dB] ≤ S21 < -2.0[dB] D: -3.0 [dB] ≤ S21 < -2.5 [dB] E: -4.0[dB] ≤ S21 < -3.0[dB] ×: S21 < -4.0 [dB] The results are shown in Table 2.

[0195] [Table 2]

[0196] The laminated glass examples 2 to 14, which correspond to the embodiments, all had a total solar radiation transmittance Tts of 80% or less, demonstrating good heat shielding properties.

[0197] Furthermore, the laminated glass in manufacturing examples 2 to 14 exhibited excellent radio wave transparency, with a maximum value of -4.0V or higher for radio wave transmission loss S21 when incident at an incident angle of 20°, 45°, or 60° with a frequency of 75-80GHz.

[0198] Thus, it was found that the laminated glass of manufacturing examples 2 to 14 has high millimeter-wave transmittance and a predetermined heat shielding property.

[0199] On the other hand, the laminated glass of Manufacturing Example 1, which corresponds to the comparative example, showed a radio wave transmission loss S21 of less than -4.0 dB at frequencies of 76 GHz and 79 GHz, regardless of the incident angle of 20°, 45°, and 60°. In addition, although not shown in Table 2, the maximum value of the radio wave transmission loss S21 at frequencies of 75-80 GHz was less than -4.0 dB for all incident angles of 20°, 45°, and 60°, indicating poor radio wave transparency.

[0200] Although various embodiments have been described above with reference to the drawings, it goes without saying that the present invention is not limited to these examples. It is clear to those skilled in the art that various modifications or alterations can be conceived within the scope of the claims, and these will naturally also fall within the technical scope of the present invention. Furthermore, the components of the above embodiments may be combined in any way without departing from the spirit of the invention.

[0201] This application is based on Japanese Patent Application No. 2021-109448 filed on June 30, 2021, and its contents are incorporated herein by reference. [Explanation of Symbols]

[0202] 10 Laminated glass 11. First glass plate 12. Second glass plate 13 Interlayer 100 vehicles 110 Opening 120 Housing 150 Rearview mirror 201 mm wave radar 202 Stereo Camera 300 radio waves

Claims

1. It comprises a first glass plate, a second glass plate, and an interlayer sandwiched between the first glass plate and the second glass plate, wherein at least one of the first glass plate and the second glass plate is Expressed as a mole percentage based on oxides, 70%≦SiO ２ ≦85% 0.0% ≦Al ２ O ３ ≦10% 0.0% ≦ B ２ O ３ ≦15% 1.5% ≤ MgO ≤ 20% 0.0% ≤ CaO ≤ 20% 0.0% ≤ SrO ≤ 5.0% 0.0% ≤ BaO ≤ 1.0% 0.0% ≤ ZnO ≤ 5.0% 1.0%≦Li ２ O≦11% 0.0%≦Na ２ O≦10% 0.0%≦K ２ O≦10% 3.0%≦R ２ O≦11% 0.01% ≦Fe ２ O ３ ≦1.00% 2.0% ≤ RO ≤ 20% Contains (R ２ O is Li ２ O, Na ２ O, K ２ (The total amount of O is represented by RO, which represents the total amount of MgO, CaO, SrO, and BaO.) Glass viscosity is 10 ２ Temperature T at which dPa·s occurs ２ The temperature is below 1650°C. Glass viscosity is 10 １２ Temperature T at which dPa·s occurs １２ The temperature is below 730°C. Relative permittivity (ε) at a frequency of 10 GHz ｒ ) is 6.5 or less, The dielectric loss tangent (tanδ) at a frequency of 10 GHz is 0.0090 or less. Laminated glass.

2. At least one of the first glass plate and the second glass plate is The average coefficient of thermal expansion between 50°C and 350°C is 40 × 10⁻⁶. －７ The laminated glass according to claim 1, wherein the temperature is 1 / K or higher.

3. At least one of the first glass plate and the second glass plate is Expressed as a mole percentage based on oxides, Al ２ O ３ -B ２ O ３ The laminated glass according to claim 1, wherein the concentration is >0.0%.

4. At least one of the first glass plate and the second glass plate is B ２ O ３ The laminated glass according to claim 1, which substantially does not contain.

5. At least one of the first glass plate and the second glass plate is Expressed as a mole percentage based on oxides, 5.0% ≤ B ２ O ３ The laminated glass according to claim 1, wherein the percentage is ≤15%.

6. At least one of the first glass plate and the second glass plate is Expressed as a mole percentage based on oxides, 0.0% ≤ B ２ O ３ The laminated glass according to claim 1, wherein the content is <5.0%.

7. At least one of the first glass plate and the second glass plate is The laminated glass according to claim 1, wherein, when the thickness is converted to 2.00 mm, the visible light transmittance Tv as defined in ISO-9050:2003 using a D65 light source is 75% or more.

8. At least one of the first glass plate and the second glass plate is The laminated glass according to claim 1, wherein, when converted to a thickness of 2.00 mm, the total solar radiation transmittance Tts, as defined in ISO-13837:2008 convention A and measured at a wind speed of 4 m / s, is 88% or less.

9. At least one of the first glass plate and the second glass plate is The temperature T １２ The laminated glass according to claim 1, wherein the temperature is 650°C or lower.

10. At least one of the first glass plate and the second glass plate is The relative permittivity (ε) of the aforementioned frequency 10 GHz ｒ The laminated glass according to claim 1, wherein the coefficient of the ion is 6.0 or less.

11. At least one of the first glass plate and the second glass plate is Expressed as a mole percentage based on oxides, 3.0% ≤ Li ２ The laminated glass according to claim 1, wherein O ≤ 10%.

12. At least one of the first glass plate and the second glass plate is Expressed as a mole percentage based on oxides, The laminated glass according to claim 1, wherein 1.8% ≤ MgO ≤ 8.0%.

13. At least one of the first glass plate and the second glass plate is Expressed as a mole percentage based on oxides, 71% ≤ SiO ２ The laminated glass according to claim 1, wherein the ratio is ≤85%.

14. At least one of the first glass plate and the second glass plate is Expressed as a mole percentage based on oxides, 0.05% ≤ Fe ２ O ３ The laminated glass according to claim 1, wherein the concentration is ≤1.00%.

15. The laminated glass according to any one of claims 1 to 14, wherein the total thickness of the first glass plate, the second glass plate, and the interlayer is 6.00 mm or less, and the visible light transmittance Tv as defined in ISO-9050:2003 using a D65 light source is 70% or more.

16. The laminated glass according to any one of claims 1 to 14, wherein the total thickness of the first glass plate, the second glass plate, and the interlayer is 6.00 mm or less, and the total solar radiation transmittance Tts, as defined in ISO-13837:2008 convention A and measured at a wind speed of 4 m / s, is 80% or less.

17. The laminated glass according to any one of claims 1 to 14, wherein the total thickness of the first glass plate, the second glass plate, and the interlayer is 6.00 mm or less, and the maximum value of the radio wave transmission loss S21 when a TM wave with a frequency of 75 GHz to 80 GHz is incident on the first glass plate at an incident angle of 60° is -4.0 dB or more.

18. The laminated glass according to any one of claims 1 to 14, wherein the total thickness of the first glass plate, the second glass plate, and the interlayer is 6.00 mm or less, and the maximum value of the radio wave transmission loss S21 when a TM wave with a frequency of 75 GHz to 80 GHz is incident on the first glass plate at an incident angle of 45° is -4.0 dB or more.

19. The laminated glass according to any one of claims 1 to 14, wherein the total thickness of the first glass plate, the second glass plate, and the interlayer is 6.00 mm or less, and the maximum value of the radio wave transmission loss S21 when a TM wave with a frequency of 75 GHz to 80 GHz is incident on the first glass plate at an incident angle of 20° is -4.0 dB or more.

20. A vehicle window glass having laminated glass according to any one of claims 1 to 14.

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