Glass compositions and their preparation methods and automotive glass

Abstract

This application relates to a glass composition, a method for preparing the same, and automotive glass. The glass composition comprises the following components by mass fraction: 58%–68% silicon dioxide, 9%–15% aluminum oxide, 15.2%–20% alkali metal oxides, 2.2%–5.5% alkaline earth metal oxides, 0.2%–1% boron oxide, 0.2%–1.6% zirconium oxide, and 0.22%–0.66% colorant. The colorant includes cobalt oxide, iron oxide, titanium oxide, and cerium oxide. The mass fractions of cobalt oxide, iron oxide, titanium oxide, and cerium oxide in the glass composition are denoted as a, b, c, and d, respectively, and satisfy the condition: 0.03 ≤ (a+b) / (c+d) ≤ 0.13. The formulation of this application ensures that the glass composition exhibits excellent UV resistance, neutral color, high visible light transmittance, and good brightness.

Description

Technical Field

[0001] This application relates to the field of glass products technology, and in particular to a glass composition, a method for preparing the same, and automotive glass. Background Technology

[0002] Automotive glass occupies approximately one-third of the vehicle's surface area. Depending on its location, automotive glass mainly includes the windshield, rear windshield, door windows, sunroof, front corner windows, and rear corner windows. Automotive glass not only requires excellent optical and mechanical properties, but also must possess properties such as abrasion resistance, heat resistance, safety, sealing, sound insulation, and protection against ultraviolet radiation to ensure the safety of drivers and passengers.

[0003] Currently, most automotive glass is made of low-emissivity (Low-E) glass. The thermal insulation properties of Low-E glass can improve the temperature difference between winter and summer inside the car, reducing air conditioning energy consumption and thus lowering fuel consumption. Simultaneously, its excellent optical properties can prevent glare and improve driver eye comfort. Additionally, a UV-resistant film can be formed on the glass surface using lamination or coating methods to obtain UV-resistant glass, which also offers thermal insulation and energy-saving / emission-reducing effects. However, the uneven thickness, poor color consistency, and susceptibility to aging and failure of UV-resistant films negatively impact the color, visible light transmittance, and UV resistance of automotive glass. Furthermore, UV-resistant films do not improve the impact resistance and scratch resistance of automotive glass, which is detrimental to the safety of occupants. Summary of the Invention

[0004] Therefore, it is necessary to provide a glass composition, a method for preparing the same, and automotive glass to overcome the problems of traditional UV-resistant glass, such as poor color, low visible light transmittance, poor UV resistance, and insufficient impact and scratch resistance.

[0005] The above-mentioned objective of this application is achieved through the following technical solution:

[0006] In a first aspect, this application provides a glass composition comprising the following components by mass fraction:

[0007] SiO2 58%~68%,

[0008] Al2O 39%~15%,

[0009] R2O 15.2%~20%,

[0010] R'O 2.2%~5.5%,

[0011] B2O3 0.2%~1%,

[0012] ZrO2 0.2%~1.6%, and

[0013] Colorant 0.22%~0.66%;

[0014] The R2O includes at least two of Li2O, Na2O, and K2O;

[0015] The R'O includes at least two of MgO, CaO and SrO;

[0016] The colorant includes Co2O3, Fe2O3, TiO2, and CeO2;

[0017] Let the mass fractions of Co2O3, Fe2O3, TiO2 and CeO2 in the glass composition be a, b, c and d, respectively, and satisfy: 0.03≤(a+b) / (c+d)≤0.13.

[0018] In one embodiment, c = 0.02%~0.13%.

[0019] In one embodiment, d = 0.18%~0.50%.

[0020] In one embodiment, a = 0.0002%~0.0035%.

[0021] In one embodiment, b = 0.0073% - 0.0394%.

[0022] In one embodiment, the glass composition comprises alkali metal oxides in the following mass fractions:

[0023] Li2O 0%~0.8%,

[0024] Na2O 9.5%~14.5%, and

[0025] K2O 3%~5.5%.

[0026] In one embodiment, the glass composition comprises the following mass fractions of alkaline earth metal oxides:

[0027] MgO 1.5%~4.1%,

[0028] CaO 0.3%~2%, and

[0029] SrO 0.1%~1%.

[0030] A second aspect of this application provides a method for preparing a glass composition, comprising the following steps:

[0031] Prepare the raw materials according to the glass composition formulation described above;

[0032] The raw materials are melted to prepare molten glass.

[0033] The molten glass is poured and molded to prepare semi-finished glass;

[0034] The semi-finished glass is annealed to prepare the glass composition.

[0035] In one embodiment, after annealing the semi-finished glass, the following steps are further included:

[0036] The annealed semi-finished glass is placed in molten salt and chemically tempered at 395℃~435℃ for 2h~8h.

[0037] In a third aspect, this application provides an automotive glass made from a glass composition prepared by the glass composition described above or by the method described above.

[0038] This application has at least the following beneficial effects:

[0039] In the glass composition of this application, TiO2 and CeO2 are used to improve the UV resistance of the glass composition, while Co2O3 and Fe2O3 are used to neutralize the color produced by TiO2 and CeO2. The colorant content is controlled at 0.22%~0.66%, and the content of the four colorants is ensured to meet the condition 0.03≤(a+b) / (c+d)≤0.13, which guarantees that the glass composition has excellent UV resistance and exhibits neutral color, high visible light transmittance, and good brightness. Simultaneously, the glass composition contains at least two alkali metal oxides and at least two alkaline earth metal oxides, which can enhance the chemical strengthening effect and reduce the coefficient of linear expansion through the mixed alkali effect and mixed alkaline earth effect, effectively improving mechanical properties and meeting the requirements for high impact resistance and high scratch resistance. Furthermore, the glass composition provided in this application has low melting difficulty, good chemical strengthening effect, and is suitable for industrial production. Detailed Implementation

[0040] To facilitate understanding of this application, the following detailed description is provided in conjunction with specific embodiments. However, this application can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a more thorough and complete understanding of the disclosure of this application.

[0041] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application.

[0042] In this application, "and / or" means any and all combinations of one or more of the related listed items. "At least one" means one or more, such as one, two, or more. "Multiple" or "several" means at least two, such as two, three, etc., and "multi-layered" means at least two layers, such as two, three, etc., unless otherwise expressly and specifically defined. In the description of this application, "several" means at least one, such as one, two, etc., unless otherwise expressly and specifically defined.

[0043] When a numerical range is disclosed in this application, the range is considered continuous and includes the minimum and maximum values ​​of the range, as well as every value between the minimum and maximum values. Furthermore, when the range refers to an integer, it includes every integer between the minimum and maximum values ​​of the range. Additionally, when multiple ranges are provided to describe a feature or characteristic, the ranges may be merged. In other words, unless otherwise specified, all ranges disclosed in this application should be understood to include any and all subranges to which they are included.

[0044] Unless otherwise specified, all steps in this application may be performed sequentially or randomly. For example, the method includes steps (a) and (b), indicating that the method may include steps (a) and (b) performed sequentially, or it may include steps (b) and (a) performed sequentially. For example, the method may also include step (c), indicating that step (c) may be added to the method in any order. For example, the method may include steps (a), (b), and (c), or it may include steps (a), (c), and (b), or it may include steps (c), (a), and (b), etc.

[0045] In this application, "above" or "below" includes the stated number. For example, "below 1" includes 1.

[0046] Unless otherwise specified, the temperature parameters in this application are permitted to be either constant-temperature treatment or variations within a certain temperature range. It should be understood that the constant-temperature treatment allows temperature fluctuations within the precision range of the instrument control, such as ±5℃, ±4℃, ±3℃, ±2℃, or ±1℃.

[0047] In this application, room temperature refers to indoor temperature, normal temperature, or general temperature. Generally, room temperature can be any of the following temperature ranges: 23℃±2℃, 25℃±5℃, or 20℃±5℃.

[0048] Traditional UV-resistant glass mostly employs lamination or coating methods to form a UV-resistant film on the glass surface. Lamination involves applying multiple layers of film, including a protective film, adhesive layer, polyester film, and UV-resistant coating, to the glass substrate. Coating involves placing a transparent UV-resistant film between two glass plates, typically using polyvinyl butyral (PVB) as the polymer matrix and nanomaterials such as nano-TiO2, nano-SiO2, nano-Al2O3, and nano-ZnO as fillers. Both methods involve reprocessing the glass surface, resulting in high production costs, unstable processing conditions, and defects such as uneven thickness and poor color, altering the glass's color and reducing its aesthetics and visible light transmittance. Furthermore, the polymer materials used in the UV-resistant film have less than ideal odor, safety, and lifespan; they are prone to aging and deterioration under prolonged sunlight exposure, losing their UV-resistant function.

[0049] Reports have suggested adding UV absorbers to glass compositions to prepare UV-resistant glass, such as titanium dioxide (TiO2), zinc oxide (ZnO), nickel monoxide (NiO), cerium dioxide (CeO2), samarium trioxide (Sm2O3), thulium trioxide (Tm2O3), and neodymium trioxide (Nd2O3). However, most UV absorbers have a wide range of colors, making it difficult for UV-resistant glass to achieve a neutral color, and reducing visible light transmittance and brightness, which makes it difficult to meet the lighting and visual requirements of automotive glass.

[0050] Based on this, in a first aspect, this application provides a glass composition to overcome the problems of poor color, low visible light transmittance, poor UV resistance, and insufficient impact and scratch resistance of traditional UV-resistant glass.

[0051] In some embodiments, the glass composition comprises the following components in mass fractions:

[0052] SiO2 58%~68%,

[0053] Al2O 39%~15%,

[0054] R2O 15.2%~20%,

[0055] R'O 2.2%~5.5%,

[0056] B2O3 0.2%~1%,

[0057] ZrO2 0.2%~1.6%, and

[0058] Colorant 0.22%~0.66%;

[0059] R2O includes at least two of Li2O, Na2O and K2O;

[0060] R'O includes at least two of MgO, CaO and SrO;

[0061] Colorants include Co2O3, Fe2O3, TiO2, and CeO2;

[0062] Let the mass fractions of Co2O3, Fe2O3, TiO2 and CeO2 in the glass composition be a, b, c and d, respectively, and satisfy: 0.03≤(a+b) / (c+d)≤0.13.

[0063] In the glass composition of this application, TiO2 and CeO2 are used to improve the UV resistance of the glass composition, while Co2O3 and Fe2O3 are used to neutralize the color produced by TiO2 and CeO2. The colorant content is controlled at 0.22%~0.66%, and the content of the four colorants is ensured to meet the condition 0.03≤(a+b) / (c+d)≤0.13, which guarantees that the glass composition has excellent UV resistance and exhibits neutral color, high visible light transmittance, and good brightness. Simultaneously, the glass composition contains at least two alkali metal oxides and at least two alkaline earth metal oxides, which can enhance the chemical strengthening effect and reduce the coefficient of linear expansion through the mixed alkali effect and mixed alkaline earth effect, effectively improving mechanical properties and meeting the requirements for high impact resistance and high scratch resistance. Furthermore, the glass composition provided in this application has low melting difficulty, good chemical strengthening effect, and is suitable for industrial production.

[0064] Silica (SiO2) is the main component forming the glass network framework and also the component with the largest mass proportion in the glass composition. Increasing the SiO2 content improves the mechanical strength, chemical stability, and thermal stability of the glass. If the SiO2 content is below 58%, the integrity of the glass melt network decreases, leading to an increase in the coefficient of linear expansion and a decrease in stability. If the SiO2 content exceeds 68%, the high-temperature viscosity of the glass increases, which is detrimental to the industrial production of this composition. Therefore, the mass proportion of SiO2 in the glass composition is 58%~68%, including but not limited to: 58%, 59%, 60%, 61%, 62%, 63%, 64%, 65%, 66%, 67%, and 68%.

[0065] Alumina (Al₂O₃) is used to make the glass network structure more complete and to improve the glass's chemical stability, hardness, elastic modulus, and impact strength. In aluminoborosilicate glasses, Al… 3+Al₂O₃ combines with free oxygen to form a glass network formic [AlO₄], creating larger porosity channels within the glass network structure. This facilitates alkali metal ion exchange, resulting in maximum compressive stress (CS) and depth of layers (DOL). In ultrathin aluminosilicate glass, an Al₂O₃ content of 9% or higher improves scratch resistance, impact resistance, crack resistance, and drop resistance. Simultaneously, an Al₂O₃ content not exceeding 15% reduces the viscosity of the molten glass, facilitating glass production and yielding high-alumina glass with a lower softening point. Therefore, the mass percentage of Al₂O₃ in the glass composition is 9%–15%, including but not limited to: 9%, 10%, 11%, 12%, 13%, 14%, and 15%.

[0066] Boron oxide (B₂O₃) is a glass network forger and flux that can lower the glass liquidus temperature, softening point temperature, and coefficient of linear expansion, while improving the thermodynamic properties of glass during chemical strengthening and hot bending processes. However, adding too much B₂O₃ to the glass will reduce the ion exchange capacity of the glass surface, which is detrimental to improving the glass's CS and DOL. Therefore, the mass percentage of B₂O₃ in the glass composition is 0.2% to 1%, including but not limited to: 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, and 1.0%.

[0067] Zirconia (ZrO2), similar to SiO2, exists in the glass network structure as a glass network formic [ZrO4]. During chemical strengthening, it can increase ion exchange kinetics and reduce surface stress relaxation, while also improving glass hardness and Young's modulus, thus enhancing its weather resistance and stability. However, adding too much ZrO2 to glass will significantly increase the glass melting temperature, which is detrimental to glass melting and forming. Therefore, the mass percentage of ZrO2 in the glass composition is 0.2% to 1.6%, including but not limited to: 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, 1.0%, 1.1%, 1.2%, 1.3%, 1.4%, 1.5%, and 1.6%.

[0068] The colorants include cobalt oxide (Co2O3), iron oxide (Fe2O3), titanium oxide (TiO2), and cerium oxide (CeO2). TiO2 and CeO2 are used to improve the UV resistance of the glass composition, while Co2O3 and Fe2O3 are used to neutralize the color produced by TiO2 and CeO2. By utilizing the synergistic effect of these four colorants and precisely controlling their content, the glass composition can be ensured to have excellent UV resistance, exhibiting neutral color, high visible light transmittance, and good brightness. The colorants constitute 0.22% to 0.66% of the glass composition by mass, including but not limited to: 0.22%, 0.25%, 0.28%, 0.30%, 0.32%, 0.35%, 0.38%, 0.4%, 0.42%, 0.45%, 0.48%, 0.5%, 0.52%, 0.55%, 0.58%, 0.6%, 0.62%, 0.64%, and 0.66%. Meanwhile, the mass percentage of the four colorants in the glass composition should satisfy 0.03≤(a+b) / (c+d)≤0.13, and the ratio of (a+b) / (c+d) includes, but is not limited to: 0.03, 0.04, 0.05, 0.06, 0.07, 0.08, 0.09, 0.10, 0.11, 0.12 and 0.13.

[0069] TiO2 is an intermediate oxide in glass, possessing a strong ability to absorb ultraviolet light. It absorbs the violet and blue light bands of the visible light spectrum, giving the glass a pale yellow hue. When used alone, its UV protection is limited; it is usually used in combination with CeO2 to achieve better UV resistance. Optionally, c = 0.02%~0.13%, meaning the mass fraction of TiO2 in the glass composition is 0.02%~0.13%, including but not limited to: 0.02%, 0.03%, 0.04%, 0.05%, 0.06%, 0.07%, 0.08%, 0.09%, 0.10%, 0.11%, 0.12%, and 0.13%.

[0070] CeO2 significantly enhances the ability of glass to absorb ultraviolet light, and when used in conjunction with titanium dioxide, it imparts a golden-yellow hue to the glass. Simultaneously, CeO2 acts as a clarifying agent during the glass melting process. Through the reaction CeO2 → Ce2O3 + O2 at melting temperatures (e.g., 1300℃~1400℃), oxygen is released from CeO2. The released O2 diffuses into the glass melt network, forming oxygen bubbles and promoting the clarification and homogenization of the glass. Optionally, d = 0.18%~0.50%, meaning the mass fraction of CeO2 in the glass composition is 0.18%~0.50%, including but not limited to: 0.18%, 0.20%, 0.22%, 0.25%, 0.28%, 0.30%, 0.32%, 0.35%, 0.38%, 0.40%, 0.42%, 0.45%, 0.48%, and 0.50%.

[0071] Co2O3 has a strong ability to impart a bluish tint, primarily eliminating or reducing the yellow, golden, or yellowish-green hues produced by compounds such as TiO2 and CeO2, thereby obtaining an ultra-white and transparent glass composition. However, the Co2O3 content should not be too high, otherwise the glass will appear dark blue, reducing visible light transmittance and brightness. Optionally, a = 0.0002%~0.0035%, that is, the mass fraction of Co2O3 in the glass composition is 0.0002%~0.0035%, including but not limited to: 0.0002%, 0.0005%, 0.0008%, 0.0010%, 0.0012%, 0.0015%, 0.0018%, 0.0020%, 0.0022%, 0.0025%, 0.0028%, 0.0030%, 0.0032%, and 0.0035%.

[0072] Fe2O3 imparts a bluish-green tint to glass, neutralizing the yellowing caused by TiO2 and CeO2. However, the Fe2O3 content should not exceed 0.04%, otherwise it will cause the glass to appear bluish, reducing visible light transmittance and brightness. Furthermore, Fe2O3 effectively absorbs infrared radiation, reducing the heat load inside the vehicle by absorbing energy before it enters the passenger compartment. However, under sunlight, the glass gradually heats up and transfers some of the absorbed energy into the vehicle through convection and radiation, reducing ride comfort and damaging the interior and components. Optionally, b = 0.0073%-0.0394%, that is, the mass fraction of Fe2O3 in the glass composition is 0.0073%~0.0394%, including but not limited to: 0.0073%, 0.0100%, 0.0120%, 0.0150%, 0.0180%, 0.0200%, 0.0220%, 0.0250%, 0.0280%, 0.0300%, 0.0320%, 0.0340%, 0.0360%, 0.0380%, and 0.0394%.

[0073] R2O represents alkali metal oxides, including at least two of lithium oxide (Li2O), sodium oxide (Na2O), and potassium oxide (K2O). Different alkali metal oxides interact to produce a mixed alkali effect, enhancing the chemical strengthening of the glass and reducing its thermal expansion. Among these, Li... + The polarization properties of Li can effectively reduce the high-temperature viscosity of molten glass; + Its small ionic radius allows it to fill the voids in the glass, balancing free oxygen and reacting with Na in the molten salt. + K +Ion exchange can increase CS and DOL in a short time, thus giving the glass better resistance to mechanical impact. Na2O and K2O have similar properties and are mainly used to lower the high-temperature melting and refining temperatures of glass, promoting chemical strengthening. If the glass composition contains only one alkali metal oxide, i.e., R2O is selected from Li2O, Na2O, and K2O, it is not conducive to improving the chemical strengthening effect and will lead to a high coefficient of linear expansion, making the glass sheet brittle. If the R2O content is too high, the number of broken bonds in the glass increases, the glass network structure is incomplete, the thermal expansion of the glass increases, the weather resistance and stability of the glass deteriorates, and the increased volatility exacerbates the corrosion of the furnace refractory. Conversely, if the R2O content is too low, the melting of the glass becomes difficult, and the chemical strengthening effect of the glass is significantly reduced. Therefore, the mass percentage of R2O in the glass composition is 15.2% to 20%, including but not limited to: 15.2%, 15.5%, 15.8%, 16.0%, 16.5%, 17.0%, 17.5%, 18.0%, 18.5%, 19.0%, 19.5% and 20.0%.

[0074] Optionally, the glass composition comprises alkali metal oxides in the following mass fractions:

[0075] Li2O 0%~0.8%,

[0076] Na2O 9.5%~14.5%, and

[0077] K2O 3%~5.5%.

[0078] The Li₂O content in the glass composition is 0% to 0.8% by mass, including but not limited to: 0%, 0.1%, 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, and 0.8%. The Na₂O content in the glass composition is 9.5% to 14.5% by mass, including but not limited to: 9.5%, 10.0%, 10.5%, 11.0%, 11.5%, 12.0%, 12.5%, 13.0%, 13.5%, 14.0%, and 14.5%. The K₂O content in the glass composition is 3% to 5.5% by mass, including but not limited to: 3.0%, 3.2%, 3.5%, 3.8%, 4.0%, 4.2%, 4.5%, 4.8%, 5.0%, 5.2%, and 5.5%.

[0079] R'O represents alkaline earth metal oxides, including at least two of magnesium oxide (MgO), calcium oxide (CaO), and strontium oxide (SrO). These oxides effectively improve glass meltability and mechanical strength. Furthermore, the interaction between different alkaline earth metal oxides creates a mixed alkaline earth effect, enhancing the chemical strengthening effect and reducing thermal expansion. If the glass composition contains only one alkaline earth metal oxide (R'O selected from MgO, CaO, and SrO), it is detrimental to improving the chemical strengthening effect and can lead to excessively high melting temperatures. If the R'O content is too high, the glass network structure is incomplete, increasing thermal expansion and reducing weather resistance and stability. It can also hinder the growth of Li. + Na + K + It exchanges mechanical energy with molten salt via ion exchange. Conversely, if the R'O content is too low, melting the glass becomes difficult, and the mechanical properties of the glass will be significantly reduced. Therefore, the mass percentage of R'O in the glass composition is 2.2% to 5.5%, including but not limited to: 2.2%, 2.5%, 2.8%, 3.0%, 3.2%, 3.5%, 3.8%, 4.0%, 4.2%, 4.5%, 4.8%, 5.0%, 5.2%, and 5.8%.

[0080] Optionally, the glass composition comprises the following mass fractions of alkaline earth metal oxides:

[0081] MgO 1.5%~4.1%,

[0082] CaO 0.3%~2%, and

[0083] SrO 0.1%~1%.

[0084] The MgO content in the glass composition is 1.5% to 4.1% by mass, including but not limited to: 1.5%, 1.8%, 2.0%, 2.2%, 2.5%, 2.8%, 3.0%, 3.2%, 3.5%, 3.8%, 4.0%, and 4.1%. The CaO content in the glass composition is 0.3% to 2% by mass, including but not limited to: 0.3%, 0.5%, 0.8%, 1.0%, 1.2%, 1.4%, 1.6%, 1.8%, and 2.0%. The SrO content in the glass composition is 0.1% to 1% by mass, including but not limited to: 0.1%, 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, and 1.0%.

[0085] Optionally, the coefficient of linear expansion of the glass composition in the temperature range of 30°C to 300°C is 80 × 10⁻⁶. -7 / ℃~105×10 -7 / ℃.

[0086] Optionally, the annealing point of the glass composition is 630°C to 710°C.

[0087] Optionally, the melting temperature of the glass composition is 1545℃~1605℃.

[0088] Optionally, the visible light transmittance of the glass composition is ≥87%, and more preferably 86%~93%.

[0089] Optionally, the ultraviolet light transmittance of the glass composition is ≤60%, and more preferably 25%~60%.

[0090] Optionally, the color values ​​of the glass composition satisfy: L=93~97, a=-0.7~-0.1, b=0~0.6.

[0091] Understandably, in the Lab color space, L represents lightness or luminance, with a value ranging from 0 to 100; the higher the value, the higher the lightness. a represents red-green tint, with a value ranging from -128 to +127; as the value increases, the color transitions from green to magenta. The closer the value of a is to 0, the closer the color is to neutral. b represents blue-yellow tint, with a value ranging from -128 to +127; as the value increases, the color transitions from blue to yellow. The closer the value of b is to 0, the closer the color is to neutral. The glass composition of this application satisfies the following color values: L = 93~97, a = -0.7~-0.1, b = 0~0.6, exhibiting high lightness and neutral color.

[0092] Optionally, the CS value of the glass composition is 700MPa~780MPa.

[0093] Optionally, the DOL value of the glass composition is 30 μm to 60 μm.

[0094] In a second aspect, this application provides a method for preparing a glass composition, used to prepare the glass composition as described above.

[0095] In some embodiments, the method for preparing the glass composition includes the following steps:

[0096] S100: Prepare raw materials according to the glass composition formulation described above;

[0097] S200: Melting raw materials to prepare molten glass;

[0098] S300: Casting molten glass into semi-finished glass products;

[0099] S400: Annealing semi-finished glass to prepare a glass composition.

[0100] The preparation method of the glass composition is described in detail below using a step-by-step approach.

[0101] S100: Prepare raw materials according to the formulation of the glass composition as described above.

[0102] Understandably, the raw materials for the glass composition can be oxides, or the corresponding hydroxides or salts of oxides. For example, the SiO2 source can be quartz sand, sodium silicate, potassium silicate, aluminum silicate, and calcium silicate; the Al2O3 source can be aluminum oxide and aluminum hydroxide; the Na2O source can be sodium silicate, sodium carbonate, and sodium bicarbonate; the K2O source can be potassium carbonate and potassium bicarbonate; the CaO source can be dolomite, quicklime, and limestone; and the B2O3 source can be borax and boric acid. The raw materials for each oxide are weighed according to the glass composition formula, and then mechanically mixed for 15 to 45 minutes to improve the mixing uniformity of the raw materials, increase the glass melting rate, and enhance the uniformity of the molten glass.

[0103] S200: Melt the raw materials to prepare molten glass.

[0104] Optionally, the melting process includes the following steps: pouring the uniformly mixed raw materials into a precious metal crucible and melting at 1520℃~1610℃ for 6h~10h to obtain molten glass. The melting temperature is 1520℃~1610℃, including but not limited to: 1520℃, 1530℃, 1540℃, 1550℃, 1560℃, 1570℃, 1580℃, 1590℃, 1600℃, and 1610℃; the melting time is 6h~10h, including but not limited to: 6h, 6.5h, 7h, 7.5h, 8h, 8.5h, 9h, 9.5h, and 10h.

[0105] S300: Casting molten glass into semi-finished glass products.

[0106] Optionally, the casting process includes the following steps: pouring molten glass into a stainless steel mold to form a semi-finished glass product.

[0107] S400: Annealing semi-finished glass to prepare a glass composition.

[0108] Optionally, the annealing process includes the following steps: annealing the semi-finished glass at 630℃~700℃ for 12h~24h, followed by cooling to room temperature to obtain a glass composition. The annealing temperature is 630℃~700℃, including but not limited to: 630℃, 640℃, 650℃, 660℃, 670℃, 680℃, 690℃, and 700℃; the annealing time is 12h~24h, including but not limited to: 12h, 13h, 14h, 15h, 16h, 17h, 18h, 19h, 20h, 21h, 22h, 23h, and 24h.

[0109] Optionally, after annealing the semi-finished glass, the following step is further included: placing the annealed semi-finished glass in molten salt and chemically tempering it at 395℃~435℃ for 2h~8h. The molten salt includes one or more of lithium nitrate (LiNO3), sodium nitrate (NaNO3), and potassium nitrate (KNO3), and may further be KNO3; the chemical tempering temperature is 395℃~435℃, including but not limited to: 395℃, 400℃, 405℃, 410℃, 415℃, 420℃, 425℃, 430℃, and 435℃; the chemical tempering time is 2h~8h, including but not limited to: 2h, 3h, 4h, 5h, 6h, 7h, and 8h.

[0110] Optionally, prior to chemical tempering, the following steps are also included: cutting, grinding, CNC machining, and polishing the annealed semi-finished glass. Specifically, the annealed semi-finished glass is cut into 50mm × 50mm × (0.7mm~1.5mm) dimensions using a wire cutting machine, and then subjected to rough grinding, cleaning, fine grinding, ultrasonic cleaning, CNC edge grinding and chamfering, and polishing finishing in sequence.

[0111] In a third aspect, this application provides an automotive glass made from a glass composition as described above or a glass composition prepared by the method described above.

[0112] The following description is further illustrated with specific embodiments and comparative examples. Unless otherwise specified, the raw materials involved in the following specific embodiments and comparative examples are all commercially available. Unless otherwise specified, the instruments used are all commercially available. Unless otherwise specified, the processes involved are conventionally selected by those skilled in the art.

[0113] Example 1

[0114] Please refer to Table 1. The glass composition of this embodiment contains the following components by mass fraction: SiO2, 59.1%; Al2O3, 14%; B2O3, 0.85%; Li2O, 0%; Na2O, 14.5%; K2O, 5.5%; MgO, 3.7%; CaO, 1%; SrO, 0.5%; ZrO2, 0.6%; TiO2, 0.03%; CeO2, 0.2%; Co2O3, 0.0002%; Fe2O3, 0.0198%.

[0115] The mass percentage of alkali metal oxide R2O is 20%, the mass percentage of alkaline earth metal oxide R'O is 5.2%, the mass percentage of colorant is 0.25%, c=0.03%, d=0.2%, a=0.0002%, d=0.0198%, and the calculated value is (a+b) / (c+d)=0.09.

[0116] The specific method for preparing the glass composition in this embodiment is as follows:

[0117] Accurately weigh 1500g of the required raw materials according to the glass composition formula, and mechanically mix for 15-45 minutes; pour the raw materials into a precious metal crucible and melt and hold at 1520℃-1610℃ for 6-10 hours to obtain molten glass; pour the molten glass into a stainless steel mold to form a semi-finished glass; anneal the semi-finished glass at 630℃-700℃ for 12-24 hours, and then cool it to room temperature; cut the annealed semi-finished glass into slices of 50mm×50mm×(0.7mm-1.5mm) using a wire cutting machine, and then perform rough grinding, ordinary cleaning, fine grinding, ultrasonic cleaning, CNC edge grinding and chamfering, and polishing finishing in sequence; place the finished semi-finished glass in KNO3 molten salt at 395℃-435℃ for chemical tempering for 2-8 hours to obtain the glass composition.

[0118] Examples 2-24

[0119] The formulations of the glass compositions in Examples 2-24 are detailed in Tables 1-4, and their preparation methods are the same as those in Example 1.

[0120] Comparative Examples 1-6

[0121] The formulations of the glass compositions in Comparative Examples 1 to 6 are detailed in Table 5, and their preparation methods are the same as those in Example 1.

[0122] Test case

[0123] The above glass compositions were tested as follows, and the results are shown in Tables 1-5. The coefficient of linear expansion, annealing point, melting temperature, and color value were tested on the finished semi-finished glass, while the CS value and DOL value were tested on the chemically tempered glass compositions.

[0124] (1) Coefficient of linear expansion: The coefficient of linear expansion of the glass composition in the range of 30℃~300℃ was determined by a German Netzsch DIL-402PC horizontal dilatometer at a heating rate of 5℃ / min.

[0125] (2) Annealing point: determined according to standard ASTM C-336.

[0126] (3) Melting temperature: The viscosity was measured using an Orton RSV-1600 high-temperature viscometer and the melting temperature was calculated using the Vogel-Fulcher-Tamann formula.

[0127] (4) Optical performance: The optical performance was tested using a PerkinElmer Lambda 950 ultraviolet-visible spectrophotometer. The test items included visible light transmittance, ultraviolet light transmittance and color values ​​(L, a, b). The transmittance was tested in the full wavelength range of 200nm~2500nm. Data in the 380nm~780nm band was selected as visible light transmittance and data in the 200nm~500nm band was selected as ultraviolet light transmittance.

[0128] (5) Mechanical properties: The CS value and DOL value of the glass were measured using an FSM-6000LE surface stress meter.

[0129] As shown in Tables 1-5, the colorant content in the glass compositions of Examples 1-24 is in the range of 0.22% to 0.66%, and satisfies 0.03 ≤ (a+b) / (c+d) ≤ 0.13, thus exhibiting the following properties: a coefficient of linear expansion of 82.5 × 10⁻⁶ in the range of 30℃ to 300℃. -7 / ℃~102×10 -7 The annealing temperature is 635℃~701℃, and the melting temperature is 1547℃~1604℃. The visible light transmittance is 86.17%~92.80%, the ultraviolet light transmittance is 25.87%~60%, the brightness L is 92.82-96.92, the red-green hue a is -0.65~-0.18, and the blue-yellow hue b is 0.02~0.54. The surface compressive stress CS after chemical tempering is 708MPa~776MPa, and the compressive stress layer depth DOL is 35μm~53μm.

[0130] The only difference between Comparative Example 1 and Example 7 is the content of the four colorants. The calculation shows that (a+b) / (c+d)=0.02, which means that the total content of TiO2 and CeO2 is too high, resulting in a yellowish color of the glass composition (b is 1.42), and a decrease in visible light transmittance and brightness L, making it difficult to meet the requirements of light transmission and vision for automotive glass.

[0131] The only difference between Comparative Example 2 and Example 2 is the content of the four colorants. The calculation shows that (a+b) / (c+d)=0.17, that is, the total content of Co2O3 and Fe2O3 is too high, which results in the glass composition being blue-green (b is -3.38), and the visible light transmittance and brightness L are reduced significantly, making it difficult to meet the requirements of light transmission and vision for automotive glass.

[0132] The only difference between Comparative Example 3 and Example 17 is the content of B2O3, MgO, TiO2, and CeO2. Although (a+b) / (c+d) = 0.12, which is in the range of 0.03 to 0.13, the mass ratio of the colorant is 0.19%, and the content of TiO2 and CeO2 is low, resulting in a bluish color of the glass composition (b is -4.18), a decrease in visible light transmittance and a significant decrease in brightness L, and an increase in ultraviolet light transmittance of 80.19%. This not only fails to meet the requirements of automotive glass for lighting and vision, but also poses a significant risk of damage to passengers and interior parts of the vehicle.

[0133] The only difference between Comparative Example 3 and Example 17 is the content of B2O3, MgO, TiO2, and CeO2. Although (a+b) / (c+d) = 0.12, which is in the range of 0.03 to 0.13, the mass ratio of the colorant is 0.19%, and the content of TiO2 and CeO2 is low, resulting in a bluish color of the glass composition (b is -4.18). The visible light transmittance is reduced and the brightness L is significantly reduced. In addition, the ultraviolet light transmittance increases to 80.19%, which not only fails to meet the requirements of automotive glass for lighting and vision, but also causes significant damage to drivers, passengers, and internal automotive parts.

[0134] The only difference between Comparative Example 4 and Example 22 is the content of B2O3, Li2O, MgO, TiO2, and CeO2. Although (a+b) / (c+d) = 0.03, which is in the range of 0.03 to 0.13, the mass ratio of the colorant is 0.71%, and the content of TiO2 and CeO2 is relatively high. Although it has excellent UV resistance, the color of the glass composition is yellow (b is 3.17), the visible light transmittance is reduced, and the brightness L is significantly reduced, which makes it difficult to meet the requirements of light transmission and vision for automotive glass.

[0135] The only difference between Comparative Example 5 and Example 6 is that R2O is selected only from Na2O and R'O is selected only from MgO. Although (a+b) / (c+d)=0.05, which is in the range of 0.03~0.13, and the mass percentage of the colorant is 0.60%, which is in the range of 0.22%~0.66%, it only contains Na2O and MgO, which cannot exert the mixed alkali effect and mixed alkaline earth effect. This leads to a decrease in chemically strengthened CS and DOL, an increase in the coefficient of linear expansion, and a significant reduction in mechanical properties. It is difficult to meet the requirements of high impact resistance and high scratch resistance for automotive glass, which poses a significant safety hazard to the overall safety of automobiles.

[0136] The only difference between Comparative Example 6 and Example 15 is the content of SiO2 and Al2O3. Although (a+b) / (c+d)=0.05, which is in the range of 0.03~0.13, the mass percentage of the colorant is 0.64%, which is in the range of 0.22%~0.66%. However, it only contains 1.3% Al2O3, which cannot enhance the glass network structure and porosity. This is not conducive to chemical strengthening, resulting in a decrease in chemical strengthening CS and DOL, which significantly reduces the strength of the glass body. It is difficult to meet the high impact resistance requirements of automotive glass and poses a significant safety hazard to the overall safety of automobiles.

[0137] Table 1. Formulations and properties of the glass compositions in Examples 1-6

[0138]

[0139] Table 2. Formulations and properties of the glass compositions of Examples 7-12

[0140]

[0141] Table 3. Formulations and properties of the glass compositions in Examples 13-18

[0142]

[0143] Table 4. Formulations and properties of the glass compositions of Examples 19-24

[0144]

[0145] Table 5. Formulations and properties of glass compositions in Comparative Examples 1-6

[0146]

[0147] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0148] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of protection of this application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these modifications and improvements all fall within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the appended claims.

Claims

1. A glass composition, characterized in that, Components including the following mass fractions: SiO2 58%~68%, Al2O 39%~15%, R2O 15.2%~20%, R'O 2.2%~5.5%, B2O3 0.2%~1%, ZrO2 0.2%~1.6%, and Colorant 0.22%~0.66%; The R2O comprises Li2O, Na2O, and K2O, and their mass fractions, based on the mass of the glass composition, are as follows: Li2O 0.1%~0.8%, Na2O 9.5%~14.5%, and K2O 3%~5.5%; The R'O comprises MgO, CaO, and SrO, with the following mass fractions based on the mass of the glass composition: MgO 1.5%~4.1%, CaO 0.3%~2%, and SrO 0.1%~1%; The colorant is Co2O3, Fe2O3, TiO2, and CeO2; Let the mass fractions of Co2O3, Fe2O3, TiO2 and CeO2 in the glass composition be a, b, c and d, respectively, and satisfy: 0.03≤(a+b) / (c+d)≤0.13; c=0.02%~0.13%.

2. The glass composition according to claim 1, characterized in that, d=0.18%~0.50%。 3. The glass composition according to claim 2, characterized in that, a=0.0002%~0.0035%。 4. The glass composition according to claim 3, characterized in that, b=0.0073%~0.0394%。 5. A method for preparing a glass composition, characterized in that, Includes the following steps: Prepare raw materials according to the formulation of the glass composition according to any one of claims 1 to 4; The raw materials are melted to prepare molten glass. The molten glass is poured and molded to prepare semi-finished glass. The semi-finished glass is annealed to prepare the glass composition.

6. The method for preparing the glass composition according to claim 5, characterized in that, After annealing the semi-finished glass, the following steps are also included: The annealed semi-finished glass is placed in molten salt and chemically tempered at 395℃~435℃ for 2h~8h.

7. An automotive glass, characterized in that, The glass composition is prepared by using the glass composition as described in any one of claims 1 to 4 or the glass composition prepared by any one of claims 5 to 6.

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