Highly transparent glass, method of forming same, and laminated glass and vehicle window glass

Abstract

This invention provides a high-transparency glass, its forming method, laminated glass, and automotive window glass. The forming method includes: placing a glass sheet in a heating furnace for heating treatment, and then pressing it to obtain high-transparency glass; the heating furnace includes a preheating section, a heating section, and a constant-temperature gradient section connected in sequence; the inlet temperature of the preheating section is 592-632℃, and the outlet temperature is 613-647℃, with the outlet temperature higher than the inlet temperature; the inlet temperature of the heating section is 630-664℃, and the outlet temperature is 648-674℃, with the outlet temperature higher than the inlet temperature; the temperature of the constant-temperature gradient section is 653-677℃; the inlet temperature of the heating section is greater than or equal to the outlet temperature of the preheating section, and the inlet temperature of the constant-temperature gradient section is greater than or equal to the outlet temperature of the heating section. The aforementioned high-transparency glass is lightweight and possesses high light transmittance, mechanical strength, scratch resistance, and abrasion resistance.

Description

Technical Field

[0001] This invention relates to the field of automotive window glass manufacturing, and more particularly to a high-transparency glass and its forming method, as well as laminated glass and automotive window glass. Background Technology

[0002] Automotive glass, especially windshields, generally uses automotive-grade glass sheets produced using the float glass process. Automotive-grade glass sheets include: clear glass (C), green glass (G), solar-absorbing green glass (SG), and super-solar-absorbing green glass (SD), etc.

[0003] Currently, automotive glass, especially windshields, integrates an increasing number of optical sensor components in its raised areas. These optical sensors, such as LiDAR and infrared cameras, place increasingly stringent requirements on the windshield, demanding maximum optical transmittance in the corresponding near-infrared band, such as 800-1600nm. Existing automotive glass substrates cannot meet these requirements, necessitating glass substrates with low absorption and high transmittance in the corresponding bands. Furthermore, with the widespread application of new energy vehicles, the demand for lightweighting is becoming increasingly apparent, including for automotive window glass, thus requiring lightweight improvements to automotive glass.

[0004] For windshields with integrated functions, such as LiDAR-integrated products, a glass substrate with low absorption and high transmittance optical performance in the corresponding wavelength band is required. At the same time, the thickness of the glass substrate needs to be appropriately reduced to meet the requirements of lightweighting. In addition, while maintaining the original optical performance and strength of the glass substrate, it is also necessary to improve the glass substrate's resistance to scratches and wear.

[0005] Low-absorption, high-transmittance glass sheets have different forming parameters than existing automotive glass sheets, necessitating a forming method for these types of glass sheets. Summary of the Invention

[0006] To address the aforementioned problems, the present invention aims to provide a high-transparency glass, its forming method, laminated glass, and automotive window glass. This high-transparency glass exhibits low absorption and high light transmittance, meeting the optical transmittance requirements of optical sensors and enabling its use in the manufacture of functionally integrated glass. Furthermore, it maintains high strength while reducing thickness, fulfilling the lightweight requirements of automotive glass.

[0007] To achieve the above objectives, the present invention provides a method for forming high-transparency glass, the method comprising:

[0008] The glass sheet is placed in a heating furnace for heating treatment, and then pressed into shape to obtain the high-transparency glass. The heating furnace includes a preheating section, a heating section, and a constant-temperature gradient section connected in sequence. The inlet temperature of the preheating section is 592-632℃, and the outlet temperature of the preheating section is 613-647℃, with the outlet temperature being higher than the inlet temperature. The inlet temperature of the heating section is 630-664℃, and the outlet temperature of the heating section is 648-674℃, with the outlet temperature being higher than the inlet temperature. The temperature of the constant-temperature gradient section is 653-677℃. The inlet temperature of the heating section is greater than or equal to the outlet temperature of the preheating section, and the inlet temperature of the constant-temperature gradient section is greater than or equal to the outlet temperature of the heating section.

[0009] In the above forming method, the preheating section is used for the first stage of heating the glass sheet, the heating section is used for the second stage of heating the glass sheet, and the constant temperature gradient section is used to keep the glass sheet warm and transfer it to subsequent processes. The preheating and heating sections can be roughly divided based on the softening temperature of the glass sheet. The temperature of the glass sheet in the preheating section is generally lower than its softening temperature, while the temperature of the glass sheet in the heating section is generally higher than its softening temperature. Therefore, the glass sheet begins to soften after entering the heating section. It is understood that in actual production, the heating temperature of the furnace is generally not equal to the glass's softening temperature. Therefore, the heating temperature of each section of the furnace can be adjusted accordingly based on the glass's softening temperature range, as long as the glass is heated in the preheating section but does not begin to soften, and begins to soften after entering the heating section.

[0010] In this invention, the softening temperature of the glass sheet refers to the temperature at which the glass begins to deform or soften under its own weight. For example, the softening temperature of low-absorption, high-transmittance glass sheets such as alumina glass is around 625℃. The softening temperature of glass is generally 100-120℃ lower than its softening point. The softening point refers to the temperature at which the glass begins to deform or soften under certain conditions. The softening point can be measured using the Littleten glass wire vertical elongation method, the process of which is as follows: heating and suspending with a density of 2.5 g / cm³. 3 The softening point is the temperature at which a glass fiber with a diameter of 0.55-0.75 mm and a length of 229 mm is stretched at a speed of 1 mm / min.

[0011] In the above molding method, the heating rate of the preheating section is 0.08-3.0℃ / s.

[0012] In the above forming method, the heating rate of the heating section is greater than 0℃ / s and less than or equal to 2.4℃ / s.

[0013] In some specific implementations, the heating rate of the preheating section can be greater than or equal to the heating rate of the heating section. The temperature change range in the constant-temperature gradual transition section is small, and the heating rate is very small; the heating rate of the constant-temperature gradual transition section is generally less than that of the preheating section and the heating section.

[0014] In the above molding method, the heating method of each section (preheating section, heating section, constant temperature gradual change section) can be a common heating method such as uniform heating, variable speed heating, or step heating. The present invention does not have any special limitation on the heating method.

[0015] This invention divides the heating furnace into three main heating treatment sections according to function: a preheating section, a heating section, and a constant temperature gradual change section. Each section can be further divided according to the actual situation of the equipment (such as the position and number of heating components such as heating wires in the heating furnace). This invention does not have a special limitation on the number of further divisions of the preheating section, heating section, and constant temperature gradual change section, as long as the heating scheme of each section (such as heating temperature, heating rate, etc.) can be realized.

[0016] The molding method of the present invention will be further explained below using an example of a heating furnace having 9 zones:

[0017] In the above forming method, the heating furnace can specifically have nine heating zones. From the inlet end to the outlet end of the heating furnace, the heating zones are sequentially designated as Zone 1 to Zone 9. Zones 1 to 3 are preheating sections, Zones 4 to 7 are heating sections, and Zones 8 to 9 are constant temperature gradual change sections. From Zone 1 to Zone 9, the heating temperature gradually increases (overall, there is an upward trend, but it is not excluded that the temperatures of adjacent heating zones are similar, for example, the temperatures of Zones 7, 8, and 9 can be close). Each heating zone heats the glass sheet simultaneously from both above and below.

[0018] The heating temperatures of Zone 1, Zone 2, and Zone 3 are 592-647℃, Zone 4, Zone 5, and Zone 6 are 630-668℃, and Zone 7, Zone 8, and Zone 9 are 648-677℃.

[0019] According to a specific embodiment of the present invention, the glass substrate applicable to the above-described forming method provided by the present invention is a low-absorption, high-transmittance glass substrate. Ordinary glass substrates have a high iron content (e.g., ordinary clear glass has an iron content of 700-900 ppm, ordinary green glass has an iron content of 5000 ppm, and absorptive green glass has an iron content of approximately 7000 ppm). The glass substrate applicable to the present invention has an even lower iron content, generally below 150 ppm, further below 130 ppm or 110 ppm, and even further below 90 ppm; the iron content refers to the weight content of iron oxide. The lower the iron content, the lower the absorption of the glass substrate.

[0020] Furthermore, the aluminum content (alumina weight ratio) of ordinary glass sheets is generally below 1 wt%; the glass sheets suitable for the forming method of this invention can be alumina glass, with an aluminum content of 4-5 wt%. This aluminum content can improve the stability and mechanical strength of the glass, increase its toughness, and also ensure that the glass sheet softens during the forming process. In the prior art, alumina glass is typically used as electroplated glass for touchscreens in mobile communication devices. This invention, by improving the forming process of alumina glass, enables its application as automotive glass, reducing glass weight and improving its scratch and wear resistance.

[0021] In some specific embodiments, the softening point temperature of ordinary glass sheets is around 725-730℃, while the softening point temperature of the glass sheets applicable to this invention is higher, reaching 742-752℃. The annealing point temperature of the glass sheets applicable to this invention is generally 550-570℃, meaning the softening point temperature is more than 30% (e.g., 30%-37%) higher than the annealing point temperature. The softening point temperature of the glass sheets applicable to this invention is directly proportional to the annealing point temperature; the higher the softening point temperature, the higher the corresponding annealing point temperature. In the above-described forming method of this invention, the heating temperature of the first zone can be higher than the annealing point temperature of the glass sheet.

[0022] In some specific embodiments, the alumina glass sheet used in this invention can be, but is not limited to, glass sheets from the following sources: an alumina glass sheet comprising the following components by mass fraction: 73%-76% SiO2, 4%-6% Al2O3, 2%-3% B2O3, 6%-8% CaO, 2%-4% MgO, 9%-12% Na2O, 0.1-0.3% CeO2, 0-0.1% Sb2O3, with the balance being unavoidable impurities. This alumina glass sheet can be produced through the following process: mixing raw materials satisfying the above composition with water, melting (1560-1600℃, 3-4h), clarifying (1430-1480℃, 1-2h), cooling (1150℃-1220℃) and rolling with rolling mills, annealing (70℃-560℃, 10min-20min) to obtain the glass sheet.

[0023] In the above forming method, the thickness of the glass sheet used can be less than 2.1 mm, and more specifically less than 1.8 mm, for example, 1.3-1.8 mm or 1.3-1.6 mm. The glass sheet of this invention can be comparable in thickness to ordinary glass sheets, or it can be thinner than ordinary glass sheets (around 2.1 mm thick). When the thickness of the glass sheet used in this invention is reduced compared to ordinary glass sheets, the high-transparency glass obtained after forming has lightweight characteristics, which can meet the lightweight requirements of the automotive manufacturing industry. In a specific embodiment, the heating temperature of the alumina glass sheet can be adjusted accordingly based on the thickness of the glass sheet. Generally speaking, as the thickness of the alumina glass sheet increases, the heating temperature increases accordingly.

[0024] In some specific embodiments, the glass sheet used in this invention can be obtained through a float glass production process, such as an electronic-grade float glass production process.

[0025] In the above forming method, the light absorption coefficient of the glass substrate for light with wavelengths of 800-1600 nm can be 0.04-0.2 cm⁻¹. -1 For example, 0.04cm -1 0.05cm -1 0.06cm -1 0.07cm -1 0.08cm -1 0.09cm -1 0.10cm -1 0.11cm -1 0.12cm -1 0.13cm -1 0.14cm -1 0.15cm -1 0.16cm -1 0.17cm -1 0.18cm -1 0.19cm -1 0.20cm -1 Specific values ​​and a range with any two of the above specific values ​​as endpoints. Further, the light absorption coefficient can be 0.04-0.11 cm⁻¹. -1 .

[0026] In this invention, the light absorption coefficient refers to the negative natural logarithm of the internal transmittance per centimeter of natural light passing through the glass substrate. When incident light is perpendicularly incident on the glass substrate, the light intensity is attenuated due to absorption by the glass substrate. The light absorption coefficient can be calculated by measuring the natural light transmittance of the glass substrate. Specifically, the light absorption coefficient can be calculated using the following formula:

[0027]

[0028] K is the light absorption coefficient of the glass substrate, l is the thickness of the glass substrate in the stacking direction; n is the refractive index of the glass substrate for a specific wavelength of laser light, and T is the transmittance of the glass substrate for a specific wavelength of laser light.

[0029] The overall forming temperature (i.e., hot bending forming temperature) in the forming method of the present invention is approximately in the range of 577-688°C, and further in the range of 582-683°C. This is generally at least 10°C higher than the forming temperature of existing automotive glass, at least 13°C higher, and at least 15°C higher. The above forming temperature range is applicable to the heating and forming of glass sheets with a thickness of 2.1 mm or less.

[0030] In the above forming method, the total heating time is generally controlled to be 2-5 minutes. If the heating time is too short, the forming will fail; if the heating time is too long, it will cause defects such as burns on the glass surface, distortion, lateral deviation during the glass sheet conveying process, and severe optical deformation. In some cases, it may even lead to failure to convey the glass properly and cause furnace failure.

[0031] In the above forming method, along the inlet to outlet of the heating furnace (i.e., along the transport direction of the glass sheet from inlet to outlet), the heating zones within the furnace are sequentially connected as Zone 1, Zone 2, Zone 3, Zone 4, Zone 5, Zone 6, Zone 7, Zone 8, and Zone 9. The heating temperature gradually increases from Zone 1 to Zone 9. Zones 1, 2, and 3 can be referred to as the first three zones; Zones 4, 5, and 6 as the middle three zones; and Zones 7, 8, and 9 as the last three zones. Specifically, the heating temperature gradually increases from Zone 1 to Zone 7; Zone 8 has a similar heating temperature to Zone 7; and Zone 9 has the same or similar heating temperature as Zone 8.

[0032] According to a specific embodiment of the present invention, the heating temperatures of the first zone, the second zone, and the third zone can be controlled to be between 592°C and 647°C, for example, specific values ​​such as 592°C, 594°C, 597°C, 600°C, 610°C, 620°C, 630°C, 640°C, 642°C, and 647°C, as well as ranges with any two of the above specific values ​​as endpoints. Further, the heating temperatures of the first zone, the second zone, and the third zone can be controlled to be between 594°C and 645°C, and more specifically, between 597°C and 642°C.

[0033] According to a specific embodiment of the present invention, the heating temperatures of the fourth, fifth, and sixth zones can be controlled to be 630-668°C, for example, specific values ​​such as 630°C, 640°C, 650°C, 660°C, and 668°C, as well as ranges with any two of the above specific values ​​as endpoints. Further, the heating temperatures of the fourth, fifth, and sixth zones can be controlled to be 632-666°C, and more specifically, 635-663°C.

[0034] According to a specific embodiment of the present invention, the heating temperatures of the seventh, eighth, and ninth zones can be controlled to be 648-677°C, for example, specific values ​​such as 648°C, 650°C, 660°C, 670°C, 674°C, 677°C, and 679°C, as well as ranges with any two of the above specific values ​​as endpoints. Further, the heating temperatures of the seventh, eighth, and ninth zones can be controlled to be 650-675°C, and more specifically, 653-672°C.

[0035] According to specific embodiments of the present invention, the top heating temperature of each heating section and each heating zone is generally higher than the bottom heating temperature. In some specific embodiments, heating devices are respectively provided at the top and bottom of each heating section and each heating zone in the heating furnace, so the top heating temperature and bottom heating temperature of each heating section and each heating zone can be controlled separately. In the present invention, the distance between the heating device at the top of the same heating zone and the glass sheet is greater than the distance between the heating device at the bottom and the glass sheet. Accordingly, by controlling the top heating temperature of the same heating zone to be higher than the bottom heating temperature, it can be ensured that the upper and lower surfaces of the glass sheet are heated uniformly.

[0036] Let the height of each heating zone be h. The glass sheet is located at the center line of the height direction of the heating zone. "Top" refers to the area above the glass sheet and whose vertical distance from the glass sheet is greater than 0 and less than or equal to 50%h. "Bottom" refers to the area below the glass sheet and whose vertical distance from the glass sheet is greater than 0 and less than or equal to 20%h.

[0037] In the above forming method, heating devices are respectively installed on the top and bottom left, middle, and right sides of each heating zone. Each heating zone then has separate heating temperatures for the top left, top middle, top right, bottom left, bottom middle, and bottom right positions, and these temperatures can be controlled individually. Here, the length of a heating zone is denoted as d. "Middle" refers to the position located at the centerline of each heating zone (the centerline perpendicular to the glass sheet transport direction, i.e., the centerline along the length of the heating zone); "left" refers to the area located to the left of the centerline of the heating zone, with a horizontal distance greater than 0 and less than or equal to 30%d from the centerline; and "right" refers to the area located to the right of the centerline of the heating zone, with a horizontal distance greater than 0 and less than or equal to 30%d from the centerline.

[0038] In the above molding method, the top heating temperatures of the first, second, and third zones can be controlled to be 597-647℃, for example, specific values ​​such as 597℃, 599℃, 600℃, 602℃, 610℃, 620℃, 630℃, 640℃, 642℃, 645℃, and 647℃, as well as ranges with any two of the above specific values ​​as endpoints. Further, it can be controlled to 599-645℃, and even further, to 602-642℃.

[0039] In the above molding method, the bottom heating temperatures of the first, second, and third zones can be controlled to be 592-641℃, for example, specific values ​​such as 592℃, 594℃, 600℃, 610℃, 620℃, 630℃, 639℃, 640℃, and 641℃, as well as ranges with any two of the above specific values ​​as endpoints. Further, they can be controlled to be 594-639℃, and even further, 597-636℃.

[0040] In the above molding method, the top heating temperatures of the fourth, fifth, and sixth zones can be controlled to be 634-668℃, for example, specific values ​​such as 634℃, 636℃, 639℃, 640℃, 650℃, 660℃, 663℃, 666℃, and 668℃, as well as ranges with any two of the above specific values ​​as endpoints. Further, the top heating temperatures of the fourth, fifth, and sixth zones can be controlled to be 636℃-666℃, and even further, 639℃-663℃.

[0041] In the above molding method, the bottom heating temperatures of the fourth, fifth, and sixth zones can be controlled to be 630-663℃ respectively; for example, specific values ​​such as 630℃, 632℃, 635℃, 640℃, 650℃, 658℃, 660℃, 661℃, and 663℃, as well as ranges with any two of the above specific values ​​as endpoints. Further, it can be controlled to 632-661℃, and even further, it can be controlled to 635-658℃.

[0042] In the above molding method, the top heating temperatures of zones seven, eight, and nine can be controlled to be 652-677℃, for example, specific values ​​such as 652℃, 654℃, 657℃, 660℃, 670℃, 672℃, 675℃, and 677℃, as well as ranges with any two of these specific values ​​as endpoints. Further, it can be controlled to 654-675℃, and even further, to 657-672℃.

[0043] In the above molding method, the bottom heating temperatures of zones seven, eight, and nine can be controlled to be 648-673℃, for example, specific values ​​such as 648℃, 650℃, 653℃, 660℃, 668℃, 670℃, 671℃, and 673℃, as well as ranges with any two of the above specific values ​​as endpoints. Further, it can be 650-671℃, and even further, it can be 653-668℃.

[0044] In some specific embodiments, the heating device can be a heating element. Specifically, each heating zone has at least one heating element at its top and bottom; furthermore, each heating zone has heating elements located at its top left, top middle, top right, bottom left, bottom middle, and bottom right. The heating temperature at each location in each heating zone can be the temperature of the heating element. The heating elements in each heating zone can simultaneously heat the glass sheet.

[0045] The heating furnace of this invention heats the glass sheet simultaneously from the top, bottom, left, middle, and right sides of the same heating zone, ensuring uniform heating at all locations on the glass sheet (including between the upper and lower surfaces, and between the larger, middle, and smaller ends). This results in better microscopic optical properties, which can be assessed using a refractometer, a Mohr's scanner, etc., to meet the optical requirements of automotive windshields. By employing the above heating method and controlling the molding temperature within an appropriate range, the glass can achieve a suitable viscosity, allowing it to flow and be molded without causing shape instability due to excessive flow. This facilitates a tight fit between the glass sheet and the die / cone during subsequent pressing and molding stages, resulting in better processing outcomes.

[0046] In the forming method provided by this invention, the heating temperatures of the first three zones, the middle three zones, and the last three zones are higher than those of the first three zones, the middle three zones, and the last three zones in existing forming methods. By adjusting the heating temperature, the optical properties of the formed glass can be significantly improved, especially its microscopic optical properties (e.g., significantly reducing optical distortion). Furthermore, by controlling the average heating temperature of each of the first three zones, the middle three zones, and the last three zones within a certain range, this invention ensures that the curvature of the glass precisely meets the requirements. In some specific embodiments, for the glass sheet used for side window glass, the curvature range of the glass sheet after heat treatment can meet the following requirements: radius of curvature ≥ 1000 mm; for the glass sheet used for windshield glass, the curvature range of the glass after heat treatment can meet the following requirements: radius of curvature 200-3000 mm.

[0047] According to a specific embodiment of the present invention, the average heating temperature of the first three zones in the forming method of the present invention is more than 23°C higher than the average heating temperature of the first three zones in the existing automotive glass sheet forming method. The glass sheet used in the present invention has a high softening point, and the corresponding forming temperature is also high. By controlling the average heating temperature of the first three zones in the forming method within a certain range, the curvature of the glass can be made to meet the requirements. For example, the average heating temperature of the top middle of the first three zones in the existing forming method for green glass sheets is 607°C, while the average heating temperature of the top middle of the first three zones in the forming method of the present invention can be 630°C, which is 23°C higher than the average heating temperature of the same position in the existing forming method.

[0048] Furthermore, in the molding method of the present invention, the top heating temperature of the first three zones is 5°C higher than the bottom heating temperature.

[0049] In the above molding method, the top heating temperature of the first region is 597-632℃, further can be 599-630℃, and even further can be 602-627℃; the bottom heating temperature of the first region is 592-621℃, further can be 594-613℃, and even further can be 597-616℃.

[0050] In the above molding method, the top heating temperature of the second zone is 611-639℃, further can be 613-637℃, and even further can be 616-634℃; the bottom heating temperature of the second zone is 605-629℃, further can be 607-627℃, and even further can be 610-624℃.

[0051] In the above molding method, the top heating temperature of the third zone is 625-647℃, further can be 627-645℃, and even further can be 630-642℃; the bottom heating temperature of the third zone is 613-641℃, further can be 615-639℃, and even further can be 618-636℃.

[0052] According to a specific embodiment of the present invention, the average heating temperature of the three intermediate zones in the inventive molding method is more than 17°C higher than the average heating temperature of the three intermediate zones in the existing automotive glass sheet molding method.

[0053] Furthermore, in the molding method of the invention, the top heating temperature of the middle three zones is 4°C higher than the bottom heating temperature.

[0054] In the above molding method, the top heating temperature of the fourth zone is 634-664℃, further can be 636-662℃, and even further can be 639-659℃; the top heating temperature of the fourth zone is 630-651℃, further can be 632-649℃, and even further can be 635-646℃.

[0055] In the above molding method, the top heating temperature of the fifth zone is 643-666℃, further can be 645-664℃, and even further can be 648-661℃; the bottom heating temperature of the fifth zone is 635-662℃, further can be 637-660℃, and even further can be 640-657℃.

[0056] In the above molding method, the top heating temperature of the sixth zone is 646-668℃, further can be 648-660℃, and even further can be 651-663℃; the bottom heating temperature of the sixth zone is 640-663℃, further can be 642-661℃, and even further can be 645-658℃.

[0057] According to a specific embodiment of the present invention, the average heating temperature of the last three zones of the inventive molding method is more than 5°C higher than the average heating temperature of the last three zones of the existing automotive glass sheet molding method.

[0058] Furthermore, in the molding method of the invention, the top heating temperature of the last three zones is more than 3°C higher than the bottom heating temperature.

[0059] In the above molding method, the top heating temperature of the seventh zone is 652-674℃, further can be 654-672℃, and even further can be 657-669℃; the bottom heating temperature of the seventh zone is 640-667℃, further can be 642-665℃, and even further can be 645-662℃.

[0060] In the above molding method, the top heating temperature of the eighth zone is 656-676℃, further can be 658-674℃, and even further can be 661-671℃; the bottom heating temperature of the eighth zone is 653-673℃, further can be 655-671℃, and even further can be 658-668℃.

[0061] In the above molding method, the top heating temperature of the ninth zone is 656-677℃, further can be 658-675℃, and even further can be 661-672℃; the bottom heating temperature of the ninth zone is 653-673℃, further can be 655-671℃, and even further can be 658-668℃.

[0062] Furthermore, in the forming method of the present invention, the heating temperature at the same height in each heating zone can be symmetrically distributed along the centerline so that the surface of the glass sheet is heated uniformly.

[0063] According to a specific embodiment of the present invention, the heating furnace may include at least one of a single-piece pressing forming furnace, a self-weight bending forming furnace, and a double-piece pressing forming furnace.

[0064] According to a specific embodiment of the present invention, the glass sheet after being processed in the heating furnace is generally sent from the sheet exit end of the heating furnace (zone nine) to the forming section outside the furnace for pressing and forming to form the high-transparency glass.

[0065] According to a specific embodiment of the present invention, the length of each heating zone in zones one through nine is generally 1500-4000 mm. Zones one through eight are typically used as heating zones, whose main functions are to heat the glass sheet (zones one through seven) and to maintain its temperature (zone eight). Zone nine serves as a heating transfer zone, which, in addition to maintaining the heating temperature of the glass sheet (similar to or basically the same as the heating temperature of zone eight), is also used to transport the glass sheet to the forming section. Accordingly, the transmission speed of the glass sheet in the first to eighth zones can be 50-300 mm / s, for example, specific values ​​such as 50 mm / s, 100 mm / s, 150 mm / s, 200 mm / s, 250 mm / s, 300 mm / s, etc., and a range with any two of the above specific values ​​as endpoints; the glass sheet is transmitted at a uniform speed in the ninth zone, and the transmission speed in the ninth zone is faster than that in the first eight zones. Specifically, the transmission speed of the glass sheet in the ninth zone can be 800-1500 mm / s, for example, specific values ​​such as 800 mm / s, 900 mm / s, 1000 mm / s, 1100 mm / s, 1200 mm / s, 1300 mm / s, 1400 mm / s, 1500 mm / s, etc., and a range with any two of the above specific values ​​as endpoints. In a specific implementation plan, the transmission speed of the glass sheet in each heating zone can be adjusted according to the actual thickness of the glass sheet. For example, for a thicker glass sheet, a lower transmission speed can be used and the heating temperature can be increased to ensure that the glass sheet is fully heated.

[0066] According to a specific embodiment of the present invention, the pressing process may include: sending a heat-treated glass sheet to a forming section having a concave mold and a convex mold; using the concave mold to lift the glass sheet until the upper surface of the glass sheet contacts the convex mold; the glass sheet contacts the concave mold and the convex mold simultaneously and is pressed; after pressing, the convex mold holds the glass sheet and rises; then the transfer shuttle of the forming section extends to below the convex mold and the glass sheet; after the transfer shuttle reaches its stroke position, the convex mold and the glass sheet separate; the glass sheet falls onto the transfer shuttle and is conveyed by the transfer shuttle to the annealing zone for annealing, thus completing the pressing process.

[0067] In the above-mentioned pressing and molding process, the concave mold in the molding section is located below the glass sheet, and the concave surface is a quadrilateral mold frame structure. The concave mold is in contact with the periphery of the glass sheet.

[0068] In the above forming process, the punch in the forming section is located above the glass sheet and has an arc-shaped surface that can contact the entire upper surface of the glass sheet. Furthermore, the surface of the punch may have several (two or more) small holes regularly distributed on it, the diameter of which is generally less than 5 mm. These small holes allow the punch to vacuum-adsorb and move the glass sheet.

[0069] In the above-mentioned pressing process, the pressing time is the time during which the glass sheet contacts the concave mold and the convex mold simultaneously (i.e., the mold closes). The pressing time is generally less than 2 seconds.

[0070] The present invention also provides a high-transparency (SuperClear-Light, abbreviated as SC-L) glass, which is formed by the above-described forming method.

[0071] According to a specific embodiment of the present invention, the thickness of the high-transparency glass is generally below 2.1 mm, and further may be below 1.8 mm, for example, 1.3-1.6 mm. When the glass thickness is reduced to below 1.8 mm, compared with the thickness of about 2.1 mm for ordinary automotive glass, the high-transparency glass provided by the present invention has a reduced thickness, exhibiting lightweight characteristics, while maintaining good optical performance and mechanical strength, thus meeting the lightweight requirements of the automotive manufacturing industry.

[0072] In some specific embodiments, the glass substrate with a thickness of 1.3-2.1 mm has a transmittance of 91% or more for light with a wavelength of 800-1600 nm, and the high-transmittance glass made from the glass substrate by the forming method of the present invention also maintains the above-mentioned transmittance. The high-transmittance glass (thickness 1.3-2.1 mm) has a transmittance of 91.3% or more (≥91.3%) for light with a wavelength of 800-1600 nm.

[0073] In some specific embodiments, the glass substrate with a thickness of 1.3-2.1 mm has a light absorption coefficient of 0.04-0.2 cm⁻¹ for light with wavelengths of 800-1600 nm. -1 Furthermore, it can reach 0.04-0.11cm. -1 High-transmittance glass manufactured using the molding method of this invention, based on a glass sheet, also maintains low absorption performance. This high-transmittance glass has a light absorption coefficient of 0.04-0.2 cm⁻¹ for light with wavelengths of 800-1600 nm. -1 Furthermore, it can reach 0.04-0.11cm. -1 .

[0074] The high-transmittance glass has high transmittance and low absorption in the near-infrared band, which can meet the transmittance requirements of optical sensors such as LiDAR and infrared cameras in this band, and can therefore be used to manufacture functionally integrated glass.

[0075] In some specific embodiments, the high-transparency glass exhibits high abrasion resistance. Specifically, using haze to characterize abrasion resistance, after ordinary glass sheets undergo abrasion treatment using a rotary abrasion tester (conditions: load weight 4.9N, grinding speed 2000 rpm), the haze of ordinary glass (such as existing ultra-clear glass) is ≤0.5% before abrasion treatment and ≤1% after abrasion treatment. In contrast, the high-transparency glass of the present invention exhibits a haze of ≤0.1% before abrasion treatment and the haze can be controlled to ≤0.2% after abrasion treatment, demonstrating high resistance to abrasion.

[0076] In some specific embodiments, the high-transparency glass exhibits high scratch resistance. Specifically, the Vickers hardness of the high-transparency glass can reach above 610 HV, which is more than 8% higher than the Vickers hardness of existing ultra-clear glass (550 ± 10 HV). The high-transparency glass of this invention has higher hardness, resulting in a longer service life and better durability, making it suitable for manufacturing windshields for LiDAR systems.

[0077] In some specific embodiments, the optical distortion of the high-transparency glass and / or the laminated glass made of the high-transparency glass is ≤150 mdpt; the tensile stress of the high-transparency glass and / or the laminated glass made of the high-transparency glass is <12 MPa, and the edge compressive stress of the high-transparency glass and / or the laminated glass made of the high-transparency glass is >12 MPa. The laminated glass may include two layers of the above-mentioned high-transparency glass, with a PVB (polyvinyl butyral) or other adhesive layer sandwiched between the two glass plates. In some specific embodiments, the thickness of the high-transparency glass in the laminated glass may be less than 2.1 mm, and the adhesive layer may be 0.76 mm.

[0078] In some specific implementations, the refractive index, fit, and other parameters of the laminated glass made from the high-transparency glass meet the requirements of GB9656-2003 "Automotive Safety Glass".

[0079] The present invention also provides a laminated glass comprising an outer glass plate, an inner glass plate, and an adhesive layer, wherein the adhesive layer is located between the outer glass plate and the inner glass plate; the outer glass plate and / or the inner glass plate is the aforementioned high-transparency glass.

[0080] In some specific embodiments, the adhesive layer may be made of materials such as PVB. The thickness of the adhesive layer may be less than 0.8 mm, for example, 0.76 mm.

[0081] In some specific implementations, the total thickness of the laminated glass is generally less than 4 mm.

[0082] In some specific implementations, by using thinner high-transparency glass as both the outer and inner glass sheets, the resulting laminated glass is thinner and lighter, while maintaining high optical performance and mechanical strength, and significantly improving scratch resistance and abrasion resistance. For example, laminated glass using 1.6mm thick high-transparency glass as both the inner and outer glass sheets has mechanical strength roughly equivalent to laminated glass using 2.1mm thick ordinary glass as both the inner and outer glass sheets, but its weight is reduced by more than 20%, and the total thickness of the laminated glass is reduced from 4.96mm to 3.96mm.

[0083] In some specific embodiments, both the inner and outer glass plates can be the high-transparency glass provided by the present invention, or a combination of high-transparency glass and ordinary glass plates (clear glass, green glass, dark green glass). Preferably, both the inner and outer glass plates can be high-transparency glass; furthermore, high-transparency glass of the same thickness can be used so that the same heating temperature parameters can be used for molding and processing, which facilitates production control, is beneficial to yield rate and production frequency control, and is convenient for mass production.

[0084] In some specific embodiments, the inner and outer glass panels may have the same or different compositions, but it is preferred that they have the same composition. The inner and outer glass panels may be made of high-transparency glass with the same composition.

[0085] In some specific embodiments, the inner and outer glass plates may have the same or different thicknesses. For example, the inner and outer glass plates may be selected from high-transparency glass of the following thicknesses: 1.3mm thick high-transparency glass, 1.4mm thick high-transparency glass, 1.5mm thick high-transparency glass, 1.6mm thick high-transparency glass, 1.7mm thick high-transparency glass, 1.8mm thick high-transparency glass, etc., and 2.1mm thick high-transparency glass.

[0086] This invention also provides a vehicle window glass made of the aforementioned high-transparency glass. In some specific embodiments, the vehicle window glass can be a windshield, rear windshield, side window, sunroof, etc. The high-transparency glass provided by this invention has high optical transmittance in the near-infrared band, which can meet the requirements of optical sensors such as LiDAR and infrared cameras for glass transmittance, and thus can be used to manufacture functionally integrated vehicle window glass, such as a functionally integrated windshield.

[0087] Furthermore, the laminated glass provided by this invention can maintain a high level of optical performance and mechanical strength while reducing thickness and weight, and has high resistance to scratches and wear, thus meeting the lightweight requirements of automobile manufacturing.

[0088] The beneficial effects of this invention include:

[0089] The high-transmittance glass provided by this invention is lightweight, has low absorption, and high light transmittance, especially in the 800-1600nm light band; it also has high mechanical strength, scratch resistance, and abrasion resistance. This low-absorption, high-transmittance glass can meet the light transmittance requirements of optical sensors and can be used in functionally integrated glass applications, such as windshields for LiDAR-embedded products. Detailed Implementation

[0090] In order to provide a clearer understanding of the technical features, objectives and beneficial effects of the present invention, the technical solution of the present invention will now be described in detail below, but it should not be construed as limiting the scope of implementation of the present invention.

[0091] Example 1

[0092] This embodiment provides a method for forming high-transparency glass, the method comprising:

[0093] S1. The glass sheet is sent into a heating furnace for heating treatment;

[0094] S2. The glass sheet that has undergone heat treatment is transferred from the heating furnace to the forming section for pressing and forming to obtain high-transparency glass, denoted as SC-L glass.

[0095] The glass sheet used in this embodiment is a medium-aluminum glass sheet, with an aluminum content of 4-5 wt% and an iron content of less than 150 ppm (more specifically, less than 130 ppm, or less than 110 ppm, or less than 90 ppm); the softening point of the glass sheet is 747±5℃, and the annealing point is 560±10℃. The thickness of the glass sheet is less than 2.1 mm.

[0096] The heating furnace used in this embodiment is a single-piece pressing and molding furnace.

[0097] The heating furnace is equipped with a preheating section, a heating section, and a constant-temperature gradual change section. Specifically, the heating furnace has a total of 9 heating zones. Taking the glass sheet conveying direction as left to right, the heating zones are, from left to right, zone 1, zone 2, zone 3, zone 4, zone 5, zone 6, zone 7, zone 8, and zone 9. The heating temperature gradually increases from zone 1 to zone 9. Zones 1 to 3 constitute the preheating section, zones 4 to 7 constitute the heating section, and zones 8 and 9 constitute the constant-temperature gradual change section.

[0098] Each heating zone is equipped with heating wires at the top and bottom as heating devices; the heating temperature at the top of the same heating zone is higher than the heating temperature at the bottom.

[0099] Heating elements are installed on the left, middle, and right sides at the same height. That is, each heating zone has heating elements on the top left, top middle, top right, bottom left, bottom middle, and bottom right. The temperature of each heating element is independently controlled, and the heating elements in each heating zone can heat the glass sheet simultaneously.

[0100] Here, the height of each heating zone is denoted as h, and the glass sheet is located on the center line of the height direction of the heating zone. "Top" refers to the area above the glass sheet and whose vertical distance from the glass sheet is greater than 0 and less than or equal to 50%h; "Bottom" refers to the area below the glass sheet and whose vertical distance from the glass sheet is greater than 0 and less than or equal to 20%h.

[0101] Let the length of each heating zone be d. The corresponding areas at the same height, namely the middle, left, and right, are as follows: "Middle" refers to the area located at the center line of the length direction of the heating zone; "Left" refers to the area located to the left of the center line of the length direction and whose horizontal distance from the center line is greater than 0 and less than or equal to 30%d; "Right" refers to the area located to the right of the center line of the length direction and whose horizontal distance from the center line is greater than 0 and less than or equal to 30%d.

[0102] The heating temperatures at each location in each heating zone of S1 are shown in Table 1.

[0103] The forming section in S2 that performs pressing includes a punch, a die, and a transfer shuttle.

[0104] The punch is located above the glass sheet and has an arc-shaped surface that can contact the entire upper surface of the glass sheet. The surface of the punch may have several (two or more) small holes regularly distributed on it, with the diameter of the holes generally less than 5 mm. Through these holes, the punch can vacuum-adhere the glass sheet, causing it to move.

[0105] The concave mold is located below the glass sheet, and its concave surface is a quadrilateral mold frame structure. The concave mold is in contact with the periphery of the glass sheet.

[0106] The pressing process of S2 specifically includes: using a concave mold to lift the glass sheet until the upper surface of the glass sheet contacts the convex mold; the glass sheet contacts the concave mold and the convex mold simultaneously (i.e., mold closing) and is pressed; the pressing temperature is controlled to be lower than the heating temperature of the fourth to ninth zones in the heating furnace; the pressing time is controlled to be less than 2 seconds; after pressing, the convex mold holds the glass sheet and rises, and then the transfer shuttle extends to the bottom of the convex mold and the glass sheet; after the transfer shuttle reaches its stroke, the convex mold and the glass sheet separate; the glass sheet falls onto the transfer shuttle and is transferred by the transfer shuttle to the annealing zone for annealing (annealing temperature is 520-620℃, annealing time is 10min-35min), thus completing the pressing process.

[0107] Comparative Example 1

[0108] This comparative example provides a method for forming a green glass sheet. The method includes feeding the green glass sheet into a heating furnace for heating treatment, and then sending it out of the heating furnace to a forming section for pressing and forming to obtain green glass, denoted as G glass.

[0109] The glass sheet used in this comparative example is a green glass sheet with an iron content of about 800-900 ppm; the softening point of the glass sheet is 725-730℃ and the annealing point is 560-620℃.

[0110] The heating furnace used in this comparative example is the same as that in Example 1, and the distribution of each heating zone and the distribution of the heating wires are also the same as in Example 1.

[0111] The heating temperatures at each location in each heating zone are shown in Table 1 (unit: °C). "Top Left" represents the heating temperature at the top left side, "Top Center" represents the heating temperature at the top center, "Top Right" represents the heating temperature at the top right side, "Bottom Left" represents the heating temperature at the bottom left side, "Bottom Center" represents the heating temperature at the bottom center, and "Bottom Right" represents the heating temperature at the bottom right side. The temperatures in Table 1 are thermocouple temperature readings.

[0112] Table 1

[0113]

[0114] As can be seen from Table 1, the molding temperature of existing green glass sheets is 576-658℃, while the molding temperature of the high-transparency glass of the present invention is 606-672℃. The molding temperature of the molding method provided by the present invention is even higher.

[0115] Example 2

[0116] This embodiment provides a method for forming high-transparency glass, the method comprising:

[0117] S1. The glass sheet is sent into a heating furnace for heating treatment;

[0118] S2. The glass sheet that has undergone heat treatment is transferred from the heating furnace to the forming section for pressing and forming to obtain high-transparency glass, denoted as SC-L glass.

[0119] The glass substrate used in this embodiment is a medium-aluminum glass substrate with an aluminum content of 4-5 wt% and an iron content of less than 150 ppm (more specifically, less than 130 ppm, 110 ppm, or 90 ppm); the softening point of the glass substrate is 747±5℃, and the annealing point is 560±10℃. The thickness of the glass substrate is 1.3 mm.

[0120] The molding method in this embodiment is similar to that in Embodiment 1, except that the heating temperature in S1 is different. The heating temperatures at each location in each heating zone in this embodiment are shown in Table 2 (unit: °C). The temperatures in Table 2 are thermocouple temperature readings.

[0121] Table 2

[0122]

[0123] Compared with the forming temperature of the 1.6mm thick SC-L glass in Example 1, the forming temperature of the 1.3mm thick SC-L glass is lower. The glass transfer speed from the first zone to the eighth zone is similar, and the ninth zone has a faster transfer speed than the first eight zones. It can be seen that the temperature pattern of each heating zone is: the forming temperature gradually increases from the first zone to the eighth zone; the ninth zone acts as a heat preservation and transfer zone, and its temperature is similar to that of the eighth zone.

[0124] Example 3

[0125] This embodiment provides a laminated glass, which consists of an outer glass plate, an inner glass plate, and an adhesive layer, with the adhesive layer located between the outer glass plate and the inner glass plate.

[0126] The outer glass plate and the inner glass plate are respectively the high-transparency glass SC-L prepared in Example 1; the adhesive layer is made of transparent PVB.

[0127] Comparative Example 2

[0128] This comparative example provides a laminated glass with a structure similar to that of the laminated glass in Example 3, except that the outer glass plate and the inner glass plate of the laminated glass in this comparative example are green glass prepared in Comparative Example 1.

[0129] Example 4

[0130] This embodiment provides a laminated glass with a structure similar to that of the laminated glass in Embodiment 3, except that the outer glass plate and the inner glass plate of the laminated glass in this embodiment are high-transparency glass prepared in Embodiment 2.

[0131] Test Example 1

[0132] The performance of the laminated glass of Example 3 and Comparative Example 2 was tested, and the test results are summarized in Table 3.

[0133] The laminated glass tested in Example 3 has the following composition: the high-transparency glass has a thickness of 1.6 mm, and the corresponding glass substrate has an aluminum content of 4.69 wt%, an iron content of 105 ppm, a softening point of 748℃, and an annealing point of 561℃; the adhesive layer has a thickness of 0.76 mm. The light absorption coefficient of the glass substrate is 0.11 cm⁻¹. -1 .

[0134] The laminated glass in Comparative Example 2 has the following composition: the thickness of the green glass is 1.6 mm, the corresponding iron content of the original green glass sheet is 805 ppm, the softening point is 728℃, and the annealing point is 592℃; the thickness of the adhesive layer is 0.76 mm. The light absorption coefficient of the green glass is 3.76 cm⁻¹. -1 .

[0135] The testing method is as follows:

[0136] Light absorption coefficient:

[0137] The laser wavelength used for the optical absorption coefficient is 800-1600nm, and the formula for calculating the optical absorption coefficient is:

[0138]

[0139] K is the light absorption coefficient of the glass substrate, l is the thickness of the glass substrate in the stacking direction; n is the refractive index of the glass substrate for a specific wavelength of laser light, and T is the transmittance of the glass substrate for a specific wavelength of laser light.

[0140] Vickers hardness: Resistant to scratches and abrasion

[0141] The ability to resist scratches and abrasion is characterized by Vickers hardness. The test method involves applying an indentation to the surface of a glass specimen using a diamond-shaped, non-deformed square pyramid indenter, following a prescribed trajectory and held for a specified time. The load is then divided by the surface area of ​​the indentation calculated based on the average length of its diagonals. The value is expressed in dimensionless units (HV). For detailed operating procedures and precautions, please refer to GB / T16534-2009, "Test Method for Room Temperature Hardness of Fine Ceramics".

[0142] The instrument used was a LD-XV1000A micro Vickers hardness tester.

[0143] Testing revealed that the Vickers hardness of the glass sheet of this invention is above 610 HV, and the Vickers hardness of the formed high-transparency glass also remained above 610 HV without significant change. In comparison, the Vickers hardness of commonly used automotive glass sheets is 550 ± 10 HV. It can be seen that the glass of this invention has an 8% higher hardness than commonly used automotive glass, resulting in a longer service life and better durability.

[0144] Abrasion resistance:

[0145] The abrasion resistance test method used a Taber 1700 rotary abrasion tester. The grinding wheel load was 4.9 N, the grinding speed was 2000 revolutions, and the test surface was the outer surface of the glass (facing outwards from the vehicle). The abrasion-induced haze value was obtained by subtracting the initial haze value from the final haze value. See pages 5-9 of GB / T 5137.1-2020 "Automotive Safety Glass Test Methods Part 1: Mechanical Properties Test" for details.

[0146] The glass sheet used in this invention has a haze of ≤0.1% before the abrasion test. After the abrasion test method described above, the haze of the glass sheet is ≤0.2%. The high-transparency glass formed using this glass sheet also has the same abrasion resistance (haze ≤0.1% before the abrasion test, haze ≤0.2% after the abrasion test). In comparison, the haze of commonly used automotive glass is ≤1%. It can be seen that the glass sheet and the high-transparency glass formed by this invention have even lower haze after abrasion treatment, indicating that the abrasion resistance of the high-transparency glass formed by this invention is superior to that of commonly used automotive glass.

[0147] Impact resistance:

[0148] The test method involves using a hardened steel ball with a mass of 227±2g and a diameter of approximately 38mm. The purpose of the test is to determine whether the laminated glass possesses a minimum strength or adhesive force under impact from a small hard object. The sample size is 300*300mm. For the high-temperature test, the glass is held at 40±2℃ for at least 4 hours, with an impact height of 9m. For the low-temperature test, the glass is held at -20±2℃ for at least 4 hours, with an impact height of 8.5m. The surface of the sample impacted by the steel ball is the outer surface of the automotive glass after installation, and only one impact is performed. After impact, the form and extent of sample damage are evaluated. If there are requirements for the mass of the detached fragments on the reverse side of the impact surface, the total mass of the detached fragments should also be weighed and recorded. A detached fragment mass ≤20g is considered acceptable. See pages 1-4 of GB / T 5137.1-2020 "Automotive Safety Glass Test Methods Part 1: Mechanical Properties Test" for details.

[0149] Penetration resistance:

[0150] A hardened steel ball with a mass of 2260±20g and a diameter of approximately 82mm was used. The purpose of the test was to evaluate the penetration resistance of laminated safety glass. The sample size was 300*300mm. The surface of the sample impacted by the steel ball was the inner surface of the automotive glass after installation, and only one impact was performed. After impact, the steel ball was evaluated for whether it penetrated the sample within 5 seconds; if it did not penetrate the sample within 5 seconds, it was considered "compliant". See pages 4-5 of GB / T 5137.1-2020 "Automotive Safety Glass Test Methods Part 1: Mechanical Properties Test" for details.

[0151] Head model impact:

[0152] The head model is spherical or hemispherical, made of laminated hardwood, and includes a replaceable felt cap and a wooden crossbeam. The felt cap is 5±1mm thick, and the total mass of the head model is 10±0.2kg. The laminated safety glass for the windshield is placed freely on a support, with the impact surface being the inner surface of the glass after installation. Each sample is only allowed one impact. The impact height of the head model is 1500mm, and the surface of the impact area should be approximately perpendicular to the impact direction. After impact, the radius of the annular crack, the exposed area of ​​the interlayer (PVB) or the crack length, and the mass of the flaking fragments are recorded. The standard for "passing" after impact is: annular crack radius ≤40mm, and exposed area of ​​the interlayer (PVB) ≤200mm². 2 The mass of the detached fragments should be ≤20g. See pages 11-13 of GB / T 5137.1-2020 "Test Methods for Automotive Safety Glass - Part 1: Mechanical Properties Tests" for details.

[0153] Table 3

[0154]

[0155] As can be seen from Table 3, the laminated glass made from the high-transparency glass provided by the present invention has comparable impact resistance, penetration resistance and safety to existing automotive glass while reducing weight and thickness compared to existing automotive glass, and its abrasion resistance and hardness are significantly improved.

[0156] The above tests were performed on the laminated glass of Example 4, and the test results are as follows:

[0157] Impact resistance: Meets standards (19.6g);

[0158] Penetration resistance: Meets the standard (no penetration within 5 seconds);

[0159] Impact test on the human head model: Meets the standards [circular crack radius ≤ 38.9 mm, exposed area of ​​the intermediate layer (PVB) ≤ 191 mm²]. 2 [The mass of the detached fragments is ≤18.3g]

[0160] Abrasion resistance: The haze after testing was 0.09%;

[0161] Vickers hardness: 611 HV.

[0162] The laminated glass made from the SC-L high-transparency glass of Example 1 in Example 3 has the following properties: optical distortion of 138 mdpt; tensile stress of 11.1 MPa and edge compressive stress of 15.9 MPa; and refraction, coincidence, etc., all meet the requirements of GB9656-2003.

[0163] The laminated glass made from the SC-L high-transparency glass of Example 2 in Example 4 has the following properties: optical distortion of 129 mdpt; tensile stress of 11.6 MPa and edge compressive stress of 14.7 MPa; and refractive index and fit all meet the requirements of GB9656-2003.

[0164] The transmittance of the SC-L high-transmittance glass in Example 1 was measured to be 91.6% in the 800-1600 nm wavelength range, and the transmittance of the SC-L high-transmittance glass in Example 2 was 91.8% in the same wavelength range. The light absorption coefficient of the high-transmittance glasses in Examples 1 and 2 was 0.11 cm⁻¹. -1 .

[0165] The results above show that, compared to laminated glass made from ordinary green glass, the laminated glass made from alumina glass sheets of this invention, while reducing thickness and weight by 20%, still meets the required impact resistance, penetration resistance, and impact resistance against mannequin heads, satisfying the safety requirements of automotive glass. Furthermore, the laminated glass of this invention exhibits significantly improved abrasion resistance and hardness compared to ordinary green glass laminated glass, providing better scratch and wear resistance, longer service life, and better durability. In addition, the laminated glass of this invention has high optical transmittance in the near-infrared band, meeting the optical requirements of LiDAR and other optical sensors, and can be applied to the manufacture of functionally integrated automotive window glass.

Claims

1. A method for forming high-transparency glass, the method comprising: The glass sheet is placed in a heating furnace for heating treatment, and then pressed into shape to obtain the high-transparency glass; The heating furnace includes a preheating section, a heating section, and a constant temperature gradual change section connected in sequence. The inlet temperature of the preheating section is 592-632℃, and the outlet temperature of the preheating section is 613-647℃, with the outlet temperature of the preheating section being higher than the inlet temperature. The inlet temperature of the heating section is 630-664℃, and the outlet temperature of the heating section is 648-674℃, with the outlet temperature of the heating section being higher than the inlet temperature. The temperature of the constant temperature gradual change section is 653-677℃; The inlet temperature of the heating section is greater than or equal to the outlet temperature of the preheating section, and the inlet temperature of the constant temperature gradual change section is greater than or equal to the outlet temperature of the heating section.

2. The molding method according to claim 1, wherein, The heating rate of the preheating section is 0.08-3.0℃ / s; The heating rate of the heating section is greater than 0℃ / s and less than or equal to 2.4℃ / s.

3. The molding method according to claim 1 or 2, wherein, The heating furnace has nine heating zones, which are numbered from zone 1 to zone 9 from the inlet to the outlet. Zones 1 to 3 are preheating zones, zones 4 to 7 are heating zones, and zones 8 to 9 are constant temperature gradual change zones. From zone one to zone nine, the heating temperature gradually increases; each heating zone heats the glass sheet simultaneously from both above and below. The heating temperatures of Zone 1, Zone 2, and Zone 3 are 592-647℃, Zone 4, Zone 5, and Zone 6 are 630-668℃, and Zone 7, Zone 8, and Zone 9 are 648-677℃.

4. The molding method according to claim 3, wherein, The top heating temperature in the same heating zone is higher than the bottom heating temperature. The top heating temperatures of the first, second, and third zones are 597-647℃, and the bottom heating temperatures of the first, second, and third zones are 592-641℃, respectively. The top heating temperatures of the fourth, fifth, and sixth zones are 634-668℃, and the bottom heating temperatures of the fourth, fifth, and sixth zones are 630-663℃, respectively. The top heating temperatures of zones 7, 8, and 9 are 652-677℃, and the bottom heating temperatures of zones 7, 8, and 9 are 648-673℃, respectively.

5. The molding method according to claim 3, wherein, The top heating temperature of the first zone is 597-632℃, and the bottom heating temperature of the first zone is 592-621℃.

6. The molding method according to claim 3, wherein, The top heating temperature of the second zone is 611-639℃, and the bottom heating temperature of the second zone is 605-629℃.

7. The molding method according to claim 3, wherein, The top heating temperature of the third zone is 625-647℃, and the bottom heating temperature of the third zone is 613-641℃.

8. The molding method according to claim 3, wherein, The top heating temperature of the fourth zone is 634-664℃, and the top heating temperature of the fourth zone is 630-651℃.

9. The molding method according to claim 3, wherein, The top heating temperature of the fifth zone is 643-666℃, and the bottom heating temperature of the fifth zone is 635-662℃.

10. The molding method according to claim 3, wherein, The top heating temperature of the sixth zone is 646-668℃, and the bottom heating temperature of the sixth zone is 640-663℃.

11. The molding method according to claim 3, wherein, The top heating temperature of the seventh zone is 652-674℃, and the bottom heating temperature of the seventh zone is 640-667℃.

12. The molding method according to claim 3, wherein, The top heating temperature of the eighth zone is 656-676℃, and the bottom heating temperature of the eighth zone is 653-673℃.

13. The molding method according to claim 3, wherein, The top heating temperature of the ninth zone is 656-677℃, and the bottom heating temperature of the ninth zone is 653-673℃.

14. The molding method according to claim 3, wherein, The length of each heating zone is 1500-4000mm; The glass sheet is transported at a uniform speed from the first zone to the eighth zone, with a transport speed of 50-300 mm / s. The glass sheet is accelerated during transport in zone nine, with an acceleration of 800-1500 mm / s. 2 .

15. The molding method according to claim 1, wherein, The thickness of the glass sheet is less than 2.1 mm; And / or, the light absorption coefficient of the glass substrate for light with wavelengths of 800-1600 nm is 0.04-0.2 cm⁻¹. -1 .

16. The molding method according to claim 1, wherein, The aluminum content of the glass substrate is 4-5 wt%. The iron content of the glass substrate is ≤150ppm.

17. The molding method according to claim 1, wherein, The softening point of the glass sheet is 742-752℃, and the annealing point is 550-570℃.

18. A high-transparency glass, which is formed by the forming method according to any one of claims 1-17.

19. The high-transparency glass according to claim 18, wherein, The high-transmittance glass has a transmittance of over 91.3% for light with wavelengths of 800-1600nm.

20. The high-transparency glass according to claim 18, wherein, The haze of the high-transparency glass is ≤0.1%; After being subjected to a wear treatment with a load of 4.9N and a grinding speed of 2000 revolutions, the haze of the high-transparency glass is ≤0.2%.

21. The high-transparency glass according to claim 18, wherein, The optical distortion of the high-transparency glass is ≤150 mdpt; the tensile stress of the high-transparency glass is <12 MPa; and the edge compressive stress of the high-transparency glass is >12 MPa.

22. A laminated glass comprising an outer glass plate, an inner glass plate, and an adhesive layer, the adhesive layer being located between the outer glass plate and the inner glass plate; wherein the outer glass plate and / or the inner glass plate is a high-transparency glass as described in any one of claims 18-21.

23. A vehicle window glass made of the laminated glass as described in claim 22.

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