High-hardness electronic glass and its manufacturing method and applications

Abstract

The present invention belongs to the technical field of electronic glass, and discloses a high-hardness electronic glass and its manufacturing method and application. Calculated by mass percentage, the raw materials of the high-hardness electronic glass according to the present invention include the following components: 58.3 to 62.93% of SiO2, 23.02 to 25.94% of Al2O3, 1.95 to 5.02% of B2O3, 2.07 to 4.21% of Li2O, 0 to 2.88% of Na2O, 0 to 2.29% of K2O, 0 to 3.30% of TiO2, 0 to 3.99% of ZrO2, and 0 to 4.17% of P2O5, and the total mass percentage of all components is 100%.

Description

Technical Field

[0001] This application belongs to the field of electronic glass technology, and specifically relates to high-hardness electronic glass, its manufacturing method, and applications.

Background Art

[0002] The front touch screens of mobile electronic display devices such as mobile phones and PDAs usually include a protective cover glass. As the coating material for the back cover, glass, plastic, metal, and glass ceramics are used. With the popularization of 5G, it has become clear that metal materials absorb 5G high-frequency signals. The back covers of 5G mobile phones are gradually being replaced by glass, and glass is applied as protection to the front and back covers of mobile electronic display devices. Due to frequent contact and use, the cover glass used needs to have excellent impact resistance and scratch resistance. However, current chemically strengthened high-aluminosilicate cover glass can cause scratches and micro-damage on the surface when it comes into contact with hard objects such as keys during use. Such damage shortens the service life of the device and increases the repair cost. Therefore, people have always been working hard on the development of microcrystalline glass and its products with drop resistance, pressure resistance, scratch resistance, and high transmittance.

Summary of the Invention

Problems to be Solved by the Invention

[0003] However, glass is a brittle material and contains many Griffith cracks. Although the surface compressive stress layer generated after chemical strengthening has the effect of confining cracks to a certain extent, when cracks expand beyond the depth of the compressive stress layer, the effect of preventing crack expansion disappears. Therefore, the existence of crystallized glass having both a crystal phase and a glass phase has attracted attention. The presence of the crystal phase prevents crack expansion and improves the scratch resistance and crack resistance of the glass. However, since the presence of the crystal phase also affects the transparency of the glass, it has become an urgent issue to develop an electronic glass with high transmittance and high hardness and meet the performance requirements of the front and back protection materials of mobile electronic display devices.

Means for Solving the Problems

[0004] In order to overcome the above-mentioned drawbacks of the prior art, an object of the present invention is to provide a high-hardness electronic glass, a manufacturing method thereof, and an application. In the present invention, first, a matrix glass with high transmittance is manufactured, and then through subsequent processing, a second phase that prevents crack expansion is formed to realize a high-transmittance and high-hardness electronic glass with enhanced glass hardness, which is applied as a protective layer for mobile electronic devices.

[0005] In order to achieve the above object, the present invention adopts the following technical means. The present invention discloses a high-hardness electronic glass, characterized in that, calculated by mass percentage, the raw materials of the high-hardness electronic glass contain components of 58.3 - 62.93% of SiO2, 23.02 - 25.94% of Al2O3, 1.95 - 5.02% of B2O3, 2.07 - 4.21% of Li2O, 0 - 2.88% of Na2O, 0 - 2.29% of K2O, 0 - 3.30% of TiO2, 0 - 3.99% of ZrO2, and 0 - 4.17% of P2O5, and the total mass percentage of all components is 100%.

[0006] The Vickers hardness value of the high-hardness electronic glass is 580 - 680 kgf / mm 2 is.

[0007] The present invention discloses a method for manufacturing high-hardness electronic glass, including the following steps S1 to S3: Step S1 of mixing the raw materials of the high-hardness electronic glass described in claim 1, then melting, casting and forming, and performing annealing treatment to obtain a formed glass block; Step S2 of slicing the formed glass block, performing polishing and polishing to obtain a substrate glass sheet; Step S3 of subjecting the substrate glass sheet to heat treatment to obtain high-hardness electronic glass including a crystal phase part and a glass phase part.

[0008] In the step S1: In the melting process, the temperature is raised to the first set temperature at the first heating rate, the first set temperature is maintained for the first set time, then the temperature is raised to the second set temperature at the second heating rate, the second set temperature is maintained for the second set time, then the temperature is raised to the third set temperature at the third heating rate, and the third heating rate is maintained for the third set time; the first heating rate is 10 to 15 °C / min, the first set temperature is 1000 to 1100 °C, the first set time is 30 to 45 minutes, the second heating rate is 5 to 7 °C / min, the second set temperature is 1350 to 1400 °C, the second set time is 1 to 2 hours, the third heating rate is 5 to 8 °C / min, the third set temperature is 1645 to 1650 °C, and the third set time is 4 to 5 hours.

[0009] In the step S1, the temperature of the annealing treatment is 600 to 650 °C.

[0010] In the step S2, the Vickers hardness value of the substrate glass sheet is 550 to 610 kgf / mm 2 is.

[0011] In the step S2, the average transmittance of the substrate glass sheet within the visible light range exceeds 85%.

[0012] In the step S3, the crystal phase part is any one or more of lithium silicate, lithium titanate, lithium aluminosilicate, and mullite.

[0013] In the step S3, the heat treatment includes a nucleation treatment and a crystallization treatment that are sequentially performed. The temperature of the nucleation treatment is 750 to 780 °C, the time of the nucleation treatment is 0.5 to 1 hour, the temperature of the crystallization treatment is 850 to 880 °C, and the time of the crystallization treatment is 0.5 to 1 hour. The method for manufacturing a high-hardness electronic glass according to claim 3.

[0014] The application of the high-hardness electronic glass, characterized in that the high-hardness electronic glass is used as a protective layer in a mobile electronic device.

Advantages of the Invention

[0015] The high-hardness electronic glass of the present invention has the following beneficial effects.

[0016] In the high-hardness electronic glass of the present invention, SiO2 is the network-forming element within the glass, forming an irregular, continuous network of silicon-oxygen tetrahedra [SiO4] structures, constituting the glass framework. SiO2 reduces the thermal expansion coefficient of the glass and minimizes the difference in thermal expansion coefficient with the second phase. Al2O3 is an intermediate oxide. When the glass lacks oxygen atoms, aluminum fills the gaps in the network as aluminum-oxygen octahedra [AlO6]. When excess oxygen atoms are present in the glass, aluminum penetrates into the glass structure as aluminum-oxygen tetrahedra [AlO4], strengthening the network and enhancing glass stability, reducing the thermal expansion coefficient, and improving hardness. B2O3 in the glass acts as a co-solvent by reducing the viscosity of the glass at high temperatures. Li2O is an alkali metal oxide and is an important factor in forming the second phase in the matrix glass. It lowers the glass's melting temperature, improving formability, and functions as a co-solvent without affecting glass stability, allowing for easy control of the occurrence and size of the second phase. Na2O and K2O are also alkali metal oxides, and act as good cosolvents for glass, lowering the melting temperature of glass and improving formability. P2O5 performs two functions in glass: network reinforcement and phase separation. As a network reinforcement function, P2O5 forms phosphate tetrahedrons [PO4] in glass, which bond with aluminum oxygen tetrahedrons [AlO4] and are incorporated into the silicon oxygen network, reinforcing the network and suppressing phase separation of glass. On the other hand, as a phase separation function, P 5+ The strong field strength of ZrO2 destroys the silicon-oxygen tetrahedra, which separate from the silicate network during heat treatment, promoting phase separation and precipitation. ZrO2 is a good nucleating agent for glass, and Zr 4+ Because the field strength is high, 2ー Zr 4+ The Si-O bonds are formed by absorbing free oxygen atoms in the structure. 4+ The Si-O-Zr-O-Si structure is formed, which is biased towards the SiO2 direction, and heat treatment under appropriate conditions promotes phase separation and crystallization. TiO2 is also a good crystal nucleator for glass, and is easily dissolved in the glass melt at high temperatures. 4+By participating in the silicon-oxygen network in a four-coordinated manner, it has good compatibility with the glass skeleton. However, during cooling or reheating, Ti 4+ aggregates to form titanium-containing droplets, promoting phase separation. The electronic glass composed of the above components has both high transmittance and hardness.

[0017] The present invention provides a method for manufacturing high-hardness electronic glass. The method uses a matrix glass having high transmittance, polishes and polishes the surface to make it smooth and transparent, and then performs heat treatment to generate a second phase (crystalline phase) different from the glass phase, thereby preventing further crack expansion and improving the hardness of the glass. By this method, high-hardness electronic glass suitable for the protective layer of mobile electronic devices can be obtained.

Embodiments for Carrying Out the Invention

[0018] In order for those skilled in the art to understand the features and effects of the present invention, general explanations and definitions will be given below for the terms mentioned in the specification and claims. Unless otherwise specified, all technical terms and scientific terms used in this specification shall have the ordinary meanings understood by those skilled in the art related to the present invention. In case of any conflict in interpretation, the definitions in this specification shall prevail.

[0019] The theories or mechanisms described and disclosed in this specification, regardless of their correctness, do not limit the scope of the present invention in any form. That is, the content of the present invention can be implemented without being limited to specific theories or mechanisms.

[0020] In this specification, properties such as numerical values, quantities, contents, concentrations, etc. defined in the form of numerical ranges or percentage ranges are for the sake of brevity and convenience. Therefore, the description of these numerical ranges or percentage ranges is considered to include all possible sub-ranges and individual numerical values (including integers and fractions) within the range, and is specifically disclosed.

[0021] In this specification, unless otherwise specified, terms such as "comprising", "including", "having" or similar terms include the meanings of "consisting of" and "mainly consisting of". For example, "A comprises a" includes both the meanings of "A includes a and other things" and "A includes only a".

[0022] In this specification, for the sake of brevity, not all possible combinations of the technical features in each embodiment or example are described. Therefore, as long as there is no contradiction in the combination of these technical features, the technical features in each embodiment or example can be arbitrarily combined, and all possible combinations are considered to be within the scope described in this specification.

[0023] The present invention provides high-hardness electronic glass, a manufacturing method thereof and applications.

[0024] Hereinafter, based on specific examples, the present invention will be described in more detail. It should be understood that these examples are for explaining the present invention and do not limit the scope of the present invention. Also, after reading the content of the present invention, those skilled in the art can make various changes and modifications to the present invention, and their equivalent forms are also included in the scope of the claims attached to this application.

[0025] In the following examples, general equipment and devices in the technical field may be used. For the experimental methods where specific conditions are not described in the following examples, they are carried out according to normal conditions or the conditions recommended by the manufacturer. Unless otherwise specified, various raw materials used in the following examples are general commercially available products, and their specifications are the standards commonly used by those skilled in the art. In the specification of the present invention and the following examples, unless otherwise specified, "%" represents mass percentage, "parts by mass" represents parts by mass, and the ratio represents mass ratio.

[0026] In the present invention, SiO2 is a network former in the glass, forming an irregular continuous network with the structure of silicon oxygen tetrahedra [SiO4] and constituting the glass skeleton. SiO2 can reduce the thermal expansion coefficient of the glass and decrease the difference in thermal expansion coefficient from the second phase. However, when the content of SiO2 is excessively high, the high-temperature viscosity of the glass increases, making it easier to form a silicon-rich phase and inducing the generation of the second phase. Therefore, by controlling the content of SiO2 within the range of 58.3% to 62.93%, the glass can be given a low thermal expansion coefficient.

[0027] Al2O3 is an intermediate oxide. When there is a shortage of oxygen atoms in the glass, the coordination state of aluminum becomes aluminum oxygen octahedra [AlO6] and is located in the gaps of the network. On the other hand, when there are extra oxygen atoms in the glass, the coordination state of aluminum becomes aluminum oxygen tetrahedra [AlO4], enters the glass structure, plays a role in reinforcing the network, improves the stability of the glass, reduces the thermal expansion coefficient, and increases the hardness. However, if the content of Al2O3 is excessively high, the viscosity of the matrix glass tends to increase and the forming performance deteriorates. Therefore, by controlling the content of Al2O3 within the range of 23.02% to 25.94%, it is possible to ensure the stability of the glass structure while achieving a low thermal expansion coefficient and high surface hardness.

[0028] B2O3 mainly reduces the viscosity of the glass at high temperatures and acts as a flux in melting. However, if the content is too high, the thermal expansion coefficient increases and the surface hardness of the matrix glass decreases. Therefore, by controlling the content of B2O3 within the range of 1.95% to 5.02%, it is possible to exert the flux effect while not affecting the thermal stability and surface hardness of the glass.

[0029] Li2O is an alkali metal oxide and an important component for the matrix glass to form a second phase. It can lower the melting temperature of the glass and improve the formability. However, when the content of Li2O exceeds 5%, the stability of the glass decreases, the precipitation of the second phase becomes difficult to control, and devitrification is likely to occur. Therefore, by controlling the content of Li2O within the range of 2.07% - 4.21%, the flux effect can be maintained while not compromising the stability of the glass, and the appearance (formation of the second phase) and size of the second phase can be easily controlled.

[0030] Na2O and K2O are alkali metal oxides and excellent fluxes that can lower the melting temperature of the glass and improve the formability. They are also components necessary for chemical strengthening to enhance the surface strength of the electronic glass. However, if the content is too high, the stability of the glass will decrease. Therefore, in the present invention, the content of Na2O is controlled within the range of 0 - 2.88%, and the content of K2O is controlled within the range of 0 - 2.29%, containing a small amount of alkali metal oxides.

[0031] P2O5 has two functions in the glass: network reinforcement and phase separation. The network reinforcement function is that P2O5 forms [PO4] phosphate oxygen tetrahedrons, combines with [AlO4] aluminate oxygen tetrahedrons, enters the silicon oxygen network, enhances the structural stability, and suppresses the phase separation of the glass. On the other hand, the phase separation function occurs due to the high coordination number of phosphides and the strong field strength of P 5+ destroying the silicon oxygen tetrahedron structure by depriving O 2ー to form tetrahedrons. During heat treatment, it separates from the silicate network, promotes phase separation, and when the temperature rises during the phase separation process, the glass components are concentrated, further promoting crystallization. In the present invention, the content of P2O5 is controlled within the range of 0 - 4.17%, and which of the network reinforcement or phase separation plays a major role is closely related to the content of other components in the glass.

[0032] ZrO2 is an excellent crystal nucleating agent for the glass. The electric field strength of Zr 4+ ions is high, and the surrounding O 2ー is Zr 4+They are arranged according to their own coordination numbers to form so-called "aggregates". After depriving the free oxygen in the structure, these aggregates further deprive the bridging oxygen in the glass skeleton, and the O of the Si-O bond 2ー ions are biased towards Zr 4+ to form the structure of Si-O-Zr-O-Si, thus forming aggregates. Such aggregates will cause phase separation and crystallization through heat treatment under appropriate conditions. ZrO2 improves the chemical durability and hardness of the glass. However, if the content is too high, melting becomes difficult and it is difficult to control the size of the second phase. Therefore, the content of ZrO2 is controlled within the range of 0 to 3.99%.

[0033] TiO2 is also an excellent crystal nucleating agent for glass. At high temperatures, TiO2 has a high solubility in the glass melt, and Ti 4+ participates in the silicon-oxygen network in a tetracoordinated manner and has good compatibility with the silicon-oxygen tetrahedron structure, which is the skeletal structure of the glass. However, due to the strong electric field of Ti 4+ , when the glass is cooled or reheated, Ti 4+ gathers to form droplets containing titanium, promoting phase separation. However, if the content of TiO2 is too high, the valence electrons of Ti 4+ transition between different energy levels, causing selective absorption of visible light and making the glass show yellow color. Therefore, the content of TiO2 is controlled within the range of 0 to 3.30%.

[0034] By adjusting the above component contents, the obtained glass has high transparency and surface hardness, can generate a controllable second phase after heat treatment to prevent crack propagation, and can improve the hardness of the glass.

[0035] The present invention provides a high-hardness electronic glass, and its mass percentage composition is as follows: 58.3% - 62.93% of SiO2, 23.02% - 25.94% of Al2O3, 1.95% - 5.02% of B2O3, 2.07% - 4.21% of Li2O, 0% - 2.88% of Na2O, 0% - 2.29% of K2O, 0 - 3.30% of TiO2, 0 - 3.99% of ZrO2, and 0% - 4.17% of P2O5. The total mass percentage of all components is 100%.

[0036] The present invention further provides a method for manufacturing high-hardness electronic glass. The specific procedure is as follows. Step S1: Mix the raw materials of high-hardness electronic glass and perform melting. Specifically, heat up to 1000 - 1100 °C at a rate of 10 - 15 °C / min and hold for 30 - 45 minutes. Next, heat up to 1350 - 1400 °C at a rate of 5 - 7 °C / min and hold for 1 - 2 hours. Then, heat up to 1645 - 1650 °C at a rate of 5 - 8 °C / min, hold for 4 - 5 hours, and then cast and form, and perform annealing treatment at 600 - 650 °C to obtain a formed glass block. Step S2: Slice the formed glass block, perform grinding and polishing to obtain a substrate glass sheet. Step S3: Perform heat treatment on the substrate glass sheet. Specifically, perform nucleation treatment at 750 - 780 °C for 0.5 - 1 hour and crystallization treatment at 850 - 880 °C for 0.5 - 1 hour to obtain high-hardness electronic glass containing a crystal phase part and a glass phase part. The crystal phase part is any one or more of lithium silicate, lithium titanate, lithium aluminosilicate, and mullite.

[0037] The optimal procedure and process of the method for manufacturing high-hardness electronic glass of the present invention are as follows. 1) Calculate the weight of the required raw materials based on the mass percentage of oxides and accurately weigh them. 2) Uniformly mix the weighed compounded raw materials with a mixer, pour them into a platinum crucible, put them into a high-temperature experimental furnace, heat up to 1000 °C at a rate of 10 °C / min and hold for 30 minutes. Then, heat up to 1350 °C at a rate of 5 °C / min and hold for 1 hour. Further, heat up to 1650 °C at a rate of 5 °C / min, hold for 4 hours, and then pour the glass melt into a preheated mold to form a block-shaped glass with a regular shape. Put this into an annealing furnace heated up to 600 °C and cool down to room temperature by furnace cooling. 3) Cut the annealed glass block into thin sheets with a thickness of 1.3 mm using a wire saw cutting machine. Ultrasonically clean the thin sheets with a thickness of 1.3 mm successively with alcohol and pure water, and dry them in an oven at 105 °C. Then, polish them on a polishing machine using vacuum suction, measure the thickness with a screw micrometer, and make the average thickness 1.1 mm. After cleaning and drying, polish them on a polisher using vacuum suction, measure the thickness again with a screw micrometer, and make the average thickness 1.0 mm. After cleaning and drying, obtain a transparent substrate glass sheet (matrix glass sheet). 4) Based on the dilatation softening point and glass transition temperature of the substrate glass (matrix glass), set an appropriate nucleation process (nucleation process) and crystallization process. Put the substrate glass sheet into an annealing furnace and perform heat treatment according to the process to obtain a high-hardness electronic glass containing a crystal phase and a glass phase.

[0038] (Example 1) 1) The composition of the high-hardness electronic glass calculated by mass percentage is as follows: SiO2: 59.62%, Al2O3: 24.58%, B2O3: 1.95%, Li2O: 2.12%, Na2O: 2.88%, K2O: 1.83%, TiO2: 0%, ZrO2: 3.99%, P2O5: 3.03%. Calculate the weights of the required raw materials and accurately weigh them.

[0039] 2) Uniformly mix the weighed compound raw materials with a mixer and pour them into a platinum crucible. Put this into a high-temperature experimental furnace, heat it up to 1000 °C at a rate of 10 °C / min and hold for 30 minutes. Then, heat it up to 1350 °C at a rate of 5 °C / min and hold for 1 hour. Further, heat it up to 1650 °C at a rate of 5 °C / min, hold for 4 hours, and then pour the glass melt into a preheated mold to form a block-shaped glass with a regular shape. Put this into an annealing furnace heated up to 600 °C and cool it down to room temperature by furnace cooling.

[0040] 3) Anneal the glass block, then cut it into thin sheets with a thickness of 1.3 mm using a wire saw cutter. Sequentially perform ultrasonic cleaning with alcohol and pure water, and dry it in an oven at 105 °C. Then, polish it on a polishing machine using vacuum adsorption, measure the thickness with a screw micrometer, and set the average thickness to 1.1 mm. After cleaning and drying, polish it on a polisher using vacuum adsorption, measure the thickness with a screw micrometer, and set the average thickness to 1.0 mm. After cleaning and drying, obtain a transparent substrate glass sheet.

[0041] 4) Place the substrate glass sheet in a dilatometer, measure that the glass transition temperature is 706 °C and the softening point of expansion is 823 °C, and determine that the coefficient of thermal expansion at 30 - 380 °C is 35.8×10 ー7 / °C. Use a densitometer to measure the density of the substrate glass as 2.392 g / cm 3 . Measure the transmittance at visible light wavelengths with a haze meter, and obtain the average visible light transmittance of the substrate glass as 90.3%. Measure the Vickers hardness value of the substrate glass with a Vickers hardness tester as 572 kgf / mm 2 .

[0042] 5) Based on the measured glass transition temperature and softening point of expansion, set the nucleation treatment at 780 °C for 1 hour and the crystallization treatment at 880 °C for 1 hour. Then, place the substrate glass sheet in an annealing furnace, heat it to 780 °C at a rate of 5 °C / min and hold for 1 hour. Next, heat it to 880 °C at a rate of 5 °C / min, hold for 1 hour, and then cool it down by furnace cooling to obtain a heat-treated glass sheet.

[0043] 6) Measure the Vickers hardness of the heat-treated glass with a Vickers hardness tester as 630 kgf / mm 2 [[ID=XX]] [[ID=XX]]

[0044] [[ID=XX]] (Example 2) ​1) The composition of the high-hardness electronic glass calculated by mass percentage is as follows: SiO2: 60.69%, Al2O3: 23.02%, B2O3: 5.02%, Li2O: 2.16%, Na2O: 1.89%, K2O: 0.36%, TiO2: 3.30%, ZrO2: 3.56%, P2O5: 0%. Calculate the weights of the required raw materials and accurately weigh them.

[0045] 2) Mix the weighed compound raw materials uniformly with a mixer and pour them into a platinum crucible. Place this in a high-temperature experimental furnace, heat it to 1000 °C at a rate of 10 °C / min and hold for 30 minutes. Then, heat it to 1350 °C at a rate of 5 °C / min and hold for 1 hour. Further, heat it to 1650 °C at a rate of 5 °C / min, hold for 4 hours, and then pour the glass melt into a preheated mold to form a block-shaped glass with a regular shape. Place this in an annealing furnace heated to 600 °C and cool it to room temperature by furnace cooling.

[0046] 3) Cut the annealed glass block into thin sheets with a thickness of 1.3 mm using a wire saw cutter, perform ultrasonic cleaning successively with alcohol and pure water, and dry it in a drying oven at 105 °C. Then, polish it on a polishing machine using vacuum suction, measure the thickness with a screw micrometer, and make the average thickness 1.1 mm. After cleaning and drying, polish it on a polisher using vacuum suction, measure the thickness with a screw micrometer again, and make the average thickness 1.0 mm. After cleaning and drying, obtain a transparent substrate glass sheet.

[0047] 4) Place the substrate glass sheet in a dilatometer, measure the glass transition temperature and the softening point of expansion, and determine the coefficient of thermal expansion to be 36.1×10 ー7 / °C. Measure the density of the substrate glass to be 2.432 g / cm 3 . Measure the transmittance at visible light wavelengths with a haze meter and obtain the average visible light transmittance of the substrate glass to be 85.2%. Measure the Vickers hardness value of the substrate glass with a Vickers hardness tester to be 610 kgf / mm 2 .

[0048] 5) Based on the measured glass transition temperature and dilatometric softening point, set the nucleation treatment at 760 °C for 1 hour and the crystallization treatment at 860 °C for 1 hour. Then, put the substrate glass sheet into an annealing furnace, heat it up to 780 °C at a rate of 5 °C / min, and hold for 1 hour. Next, heat it up to 880 °C at a rate of 5 °C / min, hold for 1 hour, and then cool it down by furnace cooling to obtain the heat-treated glass sheet.

[0049] 6) Measure the Vickers hardness of the heat-treated glass with a Vickers hardness tester to be 680 kgf / mm 2 and. Crush the glass into powder, and use XRD to confirm that it contains lithium titanate, which is a phase different from the glass phase.

[0050] (Example 3) 1) The composition of the high-hardness electronic glass calculated by mass percentage is as follows: SiO2: 62.12%, Al2O3: 24.61%, B2O3: 3.11%, Li2O: 4.21%, Na2O: 0.92%, K2O: 1.39%, TiO2: 0%, ZrO2: 3.64%, P2O5: 0%. Calculate the weights of the required raw materials and weigh them accurately.

[0051] 2) Uniformly mix the weighed compounded raw materials with a mixer and put them into a platinum crucible. Put this into a high-temperature experimental furnace, heat it up to 1000 °C at a rate of 10 °C / min, and hold for 30 minutes. Then, heat it up to 1350 °C at a rate of 5 °C / min and hold for 1 hour. Further, heat it up to 1650 °C at a rate of 5 °C / min, hold for 4 hours, and then pour the glass melt into a preheated mold to form a block-shaped glass with a regular shape. Put this into an annealing furnace heated up to 600 °C and cool it down to room temperature by furnace cooling.

[0052] 3) Anneal the glass block, then cut it into thin sheets with a thickness of 1.3 mm using a wire saw. Sequentially perform ultrasonic cleaning with alcohol and pure water, and then dry it in a drying oven at 105 °C. Subsequently, polish it on a polishing machine using vacuum adsorption, measure the thickness with a screw micrometer, and adjust the average thickness to 1.1 mm. After cleaning and drying, polish it on a polishing machine using vacuum adsorption, measure the thickness with a screw micrometer, and set the average thickness to 1.0 mm. After cleaning and drying, obtain a transparent substrate glass sheet.

[0053] 4) Place the substrate glass sheet in a dilatometer, measure the glass transition temperature and the softening point of expansion, and determine the coefficient of thermal expansion to be 36.2×10 ー7 / °C. Measure the density of the substrate glass with a densitometer to be 2.415 g / cm 3 . Measure the transmittance at visible light wavelengths with a haze meter, and obtain the average visible light transmittance of the substrate glass to be 89.2%. Measure the Vickers hardness value of the substrate glass with a Vickers hardness tester to be 601 kgf / mm 2 .

[0054] 5) Based on the measured glass transition temperature and softening point of expansion, set the nucleation treatment at 770 °C for 1 hour and the crystallization treatment at 870 °C for 1 hour. Then, place the substrate glass sheet in an annealing furnace, heat it up to 780 °C at a rate of 5 °C / min, and hold for 1 hour. Subsequently, heat it up to 880 °C at a rate of 5 °C / min, hold for 1 hour, and then cool it down by furnace cooling to obtain a heat-treated glass sheet.

[0055] 6) Measure the Vickers hardness of the heat-treated glass with a Vickers hardness tester and obtain 660 kgf / mm 2 . Crush the glass and measure it with XRD. It was confirmed that it contains mullite, which is a phase different from the glass phase.

[0056] (Example 4) 1) The composition of the high-hardness electronic glass calculated by mass percentage is as follows: SiO2: 60.36%, Al2O3: 23.88%, B2O3: 4.0%, Li2O: 3.15%, Na2O: 1.59%, K2O: 1.95%, TiO2: 2.99%, ZrO2: 0%, P2O5: 2.08%. Calculate the weights of the required raw materials and accurately weigh them.

[0057] 2) Mix the weighed compound raw materials uniformly with a mixer and put them into a platinum crucible. Place this in a high-temperature experimental furnace, heat it up to 1000 °C at a rate of 10 °C / min and hold for 30 minutes. Then, heat it up to 1350 °C at a rate of 5 °C / min and hold for 1 hour. Further, heat it up to 1650 °C at a rate of 5 °C / min, hold for 4 hours, and then pour the glass melt into a preheated mold to form a block-shaped glass with a regular shape. Put this into an annealing furnace heated up to 600 °C and cool it to room temperature by furnace cooling.

[0058] 3) Cut the annealed glass block into thin sheets with a thickness of 1.3 mm using a wire saw cutting machine, perform ultrasonic cleaning sequentially with alcohol and pure water, and dry it in a drying oven at 105 °C. Then, polish it on a polishing machine using vacuum adsorption, measure the thickness with a screw micrometer, and adjust the average thickness to 1.1 mm. After cleaning and drying, polish it on a polishing machine using vacuum adsorption, measure the thickness with a screw micrometer, and make the average thickness 1.0 mm. After cleaning and drying, obtain a transparent substrate glass sheet.

[0059] 4) Put the substrate glass sheet into a dilatometer, measure the glass transition temperature and the softening point of expansion, and determine the coefficient of thermal expansion to be 34.8×10 ー7 / °C. Measure the density of the substrate glass to be 2.355 g / cm 3 using a densitometer. Measure the transmittance at visible light wavelengths with a haze meter and obtain the average visible light transmittance of the substrate glass to be 87.6%. Measure the Vickers hardness value of the substrate glass to be 557 kgf / mm 2 using a Vickers hardness tester.

[0060] 5) Based on the measured glass transition temperature and dilatometric softening point, the nucleation treatment is set at 780 °C for 1 hour, and the crystallization treatment is set at 880 °C for 1 hour. Then, the substrate glass sheet is placed in an annealing furnace, heated to 780 °C at a rate of 5 °C / min, and held for 1 hour. Next, it is heated to 880 °C at a rate of 5 °C / min, held for 1 hour, and then the heat-treated glass sheet is obtained by furnace cooling.

[0061] 6) The Vickers hardness of the heat-treated glass is measured with a Vickers hardness tester to be 594 kgf / mm 2 And it is measured. The glass is crushed into powder, and it is confirmed by using XRD that it contains lithium titanate, which is another phase different from the glass phase.

[0062] (Example 5) 1) The composition of the high-hardness electronic glass calculated by mass percentage is as follows: SiO2: 61.78%, Al2O3: 24.47%, B2O3: 4.09%, Li2O: 3.20%, Na2O: 0%, K2O: 2.29%, TiO2: 0%, ZrO2: 0%, P2O5: 4.17%. Calculate the weights of the required raw materials and accurately weigh them.

[0063] 2) Mix the weighed compounded raw materials uniformly with a mixer and put them into a platinum crucible. Place this in a high-temperature experimental furnace, heat it to 1000 °C at a rate of 10 °C / min, and hold for 30 minutes. Then, heat it to 1350 °C at a rate of 5 °C / min and hold for 1 hour. Further, heat it to 1650 °C at a rate of 5 °C / min, hold for 4 hours, and then pour the glass melt into a preheated mold to form a block-shaped glass with a regular shape. Place this in an annealing furnace heated to 600 °C and cool it to room temperature by furnace cooling.

[0064] 3) Anneal the glass block, then cut it into thin sheets with a thickness of 1.3 mm using a wire saw. Perform ultrasonic cleaning successively with alcohol and pure water, and then dry it in an oven at 105 °C. After that, polish it on a polishing machine using vacuum suction, measure the thickness with a screw micrometer, and adjust the average thickness to 1.1 mm. After cleaning and drying, polish it on a polishing machine using vacuum suction, measure the thickness with a screw micrometer, and make the average thickness 1.0 mm. After cleaning and drying, obtain a transparent substrate glass sheet.

[0065] 4) Place the substrate glass sheet in a dilatometer, measure the glass transition temperature and the dilatation softening point, and determine the coefficient of thermal expansion to be 35.2×10 ー7 / °C. Measure the density of the substrate glass using a densitometer to be 2.336 g / cm 3 . Measure the transmittance at visible light wavelengths using a haze meter, and obtain the average visible light transmittance of the substrate glass to be 91.0%. Measure the Vickers hardness value of the substrate glass with a Vickers hardness tester to be 550 kgf / mm 2 .

[0066] 5) Based on the measured glass transition temperature and dilatation softening point, set the nucleation treatment at 780 °C for 1 hour and the crystallization treatment at 880 °C for 1 hour. Then, place the substrate glass sheet in an annealing furnace, heat it up to 780 °C at a rate of 5 °C / min, and hold for 1 hour. Next, heat it up to 880 °C at a rate of 5 °C / min, hold for 1 hour, and then obtain the heat-treated glass sheet by furnace cooling.

[0067] 6) Measure the Vickers hardness of the heat-treated glass with a Vickers hardness tester to be 580 kgf / mm 2 . Crush the glass into powder, and use XRD to confirm that it contains lithium silicate, which is a phase different from the glass phase.

[0068] (Example 6) 1) The composition of the high-hardness electronic glass calculated by mass percentage is as follows: SiO2: 58.30%, Al2O3: 24.03%, B2O3: 3.86%, Li2O: 2.07%, Na2O: 0.86%, K2O: 1.31%, TiO2: 2.21%, ZrO2: 3.42%, P2O5: 3.94%. Calculate the weights of the required raw materials and weigh them accurately.

[0069] 2) Mix the weighed compound raw materials uniformly with a mixer and put them into a platinum crucible. Place this in a high-temperature experimental furnace, heat it to 1000 °C at a rate of 10 °C / min and hold for 30 minutes. Then, heat it to 1350 °C at a rate of 5 °C / min and hold for 1 hour. Further, heat it to 1650 °C at a rate of 5 °C / min, hold for 4 hours, and then pour the glass melt into a preheated mold to form a block-shaped glass with a regular shape. Put this into an annealing furnace heated to 600 °C and cool it to room temperature by furnace cooling.

[0070] 3) Cut the annealed glass block into thin sheets with a thickness of 1.3 mm using a wire saw cutter, perform ultrasonic cleaning successively with alcohol and pure water, and dry it in an oven at 105 °C. Then, polish it on a polishing machine using vacuum adsorption, measure the thickness with a screw micrometer, and adjust the average thickness to 1.1 mm. After cleaning and drying, polish it on a polishing machine using vacuum adsorption, measure the thickness with a screw micrometer, and make the average thickness 1.0 mm. After cleaning and drying, obtain a transparent substrate glass sheet.

[0071] 4) Put the substrate glass sheet into a dilatometer, measure the glass transition temperature and the softening point of expansion, and determine the coefficient of thermal expansion to be 35.7×10 ー7 / °C. Measure the density of the substrate glass to be 2.410 g / cm 3 using a densitometer. Measure the transmittance at visible light wavelengths with a haze meter and obtain the average visible light transmittance of the substrate glass to be 86.8%. Measure the Vickers hardness value of the substrate glass to be 564 kgf / mm 2 using a Vickers hardness tester.

[0072] 5) Based on the measured glass transition temperature and dilatometric softening point, the nucleation treatment is set at 780 °C for 1 hour, and the crystallization treatment is set at 880 °C for 1 hour. Then, the substrate glass sheet is placed in an annealing furnace, heated to 780 °C at a rate of 5 °C / min, and held for 1 hour. Next, it is heated to 880 °C at a rate of 5 °C / min, held for 1 hour, and then the heat-treated glass sheet is obtained by furnace cooling.

[0073] 6) Measure the Vickers hardness of the heat-treated glass with a Vickers hardness tester to be 613 kgf / mm 2 and. The glass is crushed into powder, and it is confirmed by XRD that it contains lithium titanate, which is another phase different from the glass phase.

[0074] (Example 7) 1) The composition of the high-hardness electronic glass calculated by mass percentage is as follows: SiO2: 62.93%, Al2O3: 25.94%, B2O3: 4.17%, Li2O: 2.24%, Na2O: 2.34%, K2O: 0%, TiO2: 2.38%, ZrO2: 0%, P2O5: 0%. Calculate the weights of the required raw materials and accurately weigh them.

[0075] 2) The weighed compounded raw materials are uniformly mixed by a mixer and put into a platinum crucible. This is placed in a high-temperature experimental furnace, heated to 1000 °C at a rate of 10 °C / min, and held for 30 minutes. Then, it is heated to 1350 °C at a rate of 5 °C / min and held for 1 hour. Furthermore, it is heated to 1650 °C at a rate of 5 °C / min, held for 4 hours, and then the glass melt is poured into a preheated mold to form a block-shaped glass with a regular shape. This is placed in an annealing furnace heated to 600 °C and cooled to room temperature by furnace cooling.

[0076] 3) Anneal the glass block, then cut it into thin sheets with a thickness of 1.3 mm using a wire saw cutter. Perform ultrasonic cleaning sequentially with alcohol and pure water, and dry it in a drying oven at 105 °C. Then, polish it on a polishing machine using vacuum suction, measure the thickness with a screw micrometer, and adjust the average thickness to 1.1 mm. After cleaning and drying, polish it on a polisher using vacuum suction, measure the thickness with a screw micrometer, and make the average thickness 1.0 mm. After cleaning and drying, obtain a transparent substrate glass sheet.

[0077] 4) Place the substrate glass sheet in a dilatometer, measure the glass transition temperature and the softening point of expansion, and determine the coefficient of thermal expansion to be 35.7×10 ー7 / °C. Measure the density of the substrate glass with a densitometer to be 2.370 g / cm 3 . Measure the transmittance at visible light wavelengths with a haze meter, and obtain the average visible light transmittance of the substrate glass to be 88.4%. Measure the Vickers hardness value of the substrate glass with a Vickers hardness tester to be 587 kgf / mm 2 .

[0078] 5) Based on the measured glass transition temperature and softening point of expansion, set the nucleation treatment at 750 °C for 1 hour and the crystallization treatment at 850 °C for 1 hour. Then, place the substrate glass sheet in an annealing furnace, heat it up to 780 °C at a rate of 5 °C / min, and hold for 1 hour. Next, heat it up to 880 °C at a rate of 5 °C / min, hold for 1 hour, and then obtain the heat-treated glass sheet by furnace cooling.

[0079] 6) Measure the Vickers hardness of the heat-treated glass with a Vickers hardness tester to be 644 kgf / mm 2 . Crush the glass into powder and measure it with XRD. It was confirmed that it contains lithium titanate, which is a different phase from the glass phase.

[0080] Table 1 shows the glass compositions, basic properties, and types of the second phase (crystalline phase part) of Examples 1 to 7 provided by the present invention.

Table 1

[0081] (Example 8) 1) The composition of the high-hardness electronic glass calculated by mass percentage is as follows: SiO2: 59.62%, Al2O3: 24.58%, B2O3: 1.95%, Li2O: 2.12%, Na2O: 2.88%, K2O: 1.83%, TiO2: 0%, ZrO2: 3.99%, P2O5: 3.03%. Calculate the weights of the required raw materials and accurately weigh them.

[0082] 2) Mix the weighed compound raw materials uniformly with a mixer and put them into a platinum crucible. Place this in a high-temperature experimental furnace, heat it up to 1100 °C at a rate of 15 °C / min and hold for 45 minutes. Then, heat it up to 1400 °C at a rate of 7 °C / min and hold for 2 hours. Further, heat it up to 1645 °C at a rate of 8 °C / min, hold for 5 hours, and then pour the glass melt into a preheated mold to form a block-shaped glass with a regular shape. Put this into an annealing furnace heated up to 650 °C and cool it down to room temperature by furnace cooling.

[0083] 3) Cut the annealed glass block into thin sheets with a thickness of 1.3 mm using a wire saw cutter, perform ultrasonic cleaning successively with alcohol and pure water, and dry it in a drying oven at 105 °C. Then, polish it on a polishing machine using vacuum adsorption, measure the thickness with a screw micrometer, and adjust the average thickness to 1.1 mm. After cleaning and drying, polish it on a polisher using vacuum adsorption, measure the thickness with a screw micrometer, and make the average thickness 1.0 mm. After cleaning and drying, obtain a transparent substrate glass sheet.

[0084] 4) Put the substrate glass sheet into a dilatometer, measure the glass transition temperature and the softening point of expansion, and determine the coefficient of thermal expansion. Measure the density of the substrate glass with a densitometer, measure the transmittance at visible light wavelengths with a haze meter to obtain the average visible light transmittance of the substrate glass. Measure the Vickers hardness value of the substrate glass with a Vickers hardness tester.

[0085] 5) Based on the measured glass transition temperature and dilatometric softening point, the nucleation treatment is set at 780 °C for 0.5 hours, and the crystallization treatment is set at 880 °C for 0.5 hours. Then, the substrate glass sheet is placed in an annealing furnace, heated to 780 °C at a rate of 5 °C / min, and held for 1 hour. Next, it is heated to 880 °C at a rate of 5 °C / min, held for 1 hour, and then the heat-treated glass sheet is obtained by furnace cooling.

[0086] 6) The Vickers hardness of the heat-treated glass is measured with a Vickers hardness tester. The glass is crushed into powder and measured by XRD to confirm that it contains other phases different from the glass phase.

[0087] The above content is for explaining the technical idea of the present invention and does not limit the protection scope of the present invention thereto. Any changes made in the technical solution based on the technical idea proposed by the present invention are included in the scope of the claims of the present invention.

Claims

1. A high-hardness electronic glass, calculated by mass percentage, the raw materials of the high-hardness electronic glass are 58.3 to 62.93% of SiO ２ , 23.02 to 25.94% of Al ２ O ３ , 1.95 to 5.02% of B ２ O ３ , 2.07 to 4.21% of Li ２ O, 0 to 2.88% of Na ２ , 0 to 2.29% of K ２ , 0 to 3.30% of TiO ２ , 0 to 3.99% of ZrO ２ , and 0 to 4.17% of P ２ O ５ A high-hardness electronic glass characterized in that the total mass percentage of all components is 100%.

2. The Vickers hardness value of the high-hardness electronic glass is 580 to 680 kgf / mm ２ The high-hardness electronic glass according to claim 1, wherein the Vickers hardness value is as defined above.

3. A method for manufacturing high-hardness electronic glass, after mixing the raw materials of the high-hardness electronic glass according to Claim 1, melting, casting and forming, and performing annealing treatment to obtain a formed glass block in step S1; slicing the formed glass block, polishing and buffing to obtain a substrate glass sheet in step S2; performing heat treatment on the substrate glass sheet to obtain high-hardness electronic glass including a crystalline phase part and a glass phase part in step S3; A method for manufacturing high-hardness electronic glass including the above steps.

4. In step S1, in the melting process, the temperature is raised to a first set temperature at a first heating rate, the first set temperature is held for a first set time, then the temperature is raised to a second set temperature at a second heating rate, the second set temperature is held for a second set time, then the temperature is raised to a third set temperature at a third heating rate, and the third heating rate is held for a third set time; the first heating rate is 10-15 °C / min, the first set temperature is 1000-1100 °C, the first set time is 30-45 minutes, the second heating rate is 5-7 °C / min, the second set temperature is 1350-1400 °C, the second set time is 1-2 hours, the third heating rate is 5-8 °C / min, the third set temperature is 1645-1650 °C, and the third set time is 4-5 hours. The method for manufacturing high-hardness electronic glass according to Claim 3.

5. In step S1, the temperature of the annealing treatment is 600-650 °C. The method for manufacturing high-hardness electronic glass according to Claim 3.

6. In the step S2, the Vickers hardness value of the substrate glass sheet is 550 to 610 kgf / mm ２ The method for manufacturing a high-hardness electronic glass according to claim 3, wherein the Vickers hardness value is as described above.

7. In step S2, the average transmittance within the visible light range of the substrate glass sheet exceeds 85%. The method for manufacturing high-hardness electronic glass according to Claim 3.

8. In step S3, the crystalline phase part is any one or more of lithium silicate, lithium titanate, lithium aluminosilicate, and mullite. The method for manufacturing high-hardness electronic glass according to Claim 3.

9. In step S3, the heat treatment includes a nucleation treatment and a crystallization treatment performed sequentially. The temperature of the nucleation treatment is 750-780 °C, the time of the nucleation treatment is 0.5-1 hour, the temperature of the crystallization treatment is 850-880 °C, and the time of the crystallization treatment is 0.5-1 hour. The method for manufacturing high-hardness electronic glass according to Claim 3.

10. Application of high-hardness electronic glass, characterized in that the high-hardness electronic glass according to claim 1 is used as a protective layer in a mobile electronic device.

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