Microcrystalline glass, method for preparing the same, glass product and application thereof

Abstract

The application relates to a microcrystalline glass and a preparation method, glass product and application thereof, which comprises 35wt%-55wt% of SiO2, 20wt%-30wt% of Al2O3, 0wt%-6wt% of MgO, 0wt%-10wt% of ZnO, 0.5wt%-3wt% of B2O3, 0wt%-3wt% of P2O5, 0wt%-3wt% of Li2O, 0wt%-6wt% of Na2O, 0wt%-6wt% of TiO2 and 0wt%-6wt% of ZrO2 according to mass percentage; the microcrystalline glass comprises spinel crystal phase, zirconia crystal phase and spodumene crystal phase, the total crystallinity is 25%-45%, and the average grain size of the crystal phase is 10nm-50nm. The microcrystalline glass has good optical and mechanical properties, low raw material cost and can be prepared through a simple process.

Description

Technical Field

[0001] The present invention relates to the technical field of microcrystalline glass, and in particular to microcrystalline glass and a preparation method thereof, glass products and applications. Background Art

[0002] Glass-ceramics has good application prospects in the display field because it combines the properties of glass and ceramics. Traditional glass-ceramics uses a lithium-aluminum-silicon system with a high lithium content to form the crystalline phase in the glass-ceramics, and the raw material cost is relatively high. Since electronic products have high requirements for the transparency of the cover glass, the selected glass-ceramics must have a high transmittance. The transmittance of glass-ceramics is affected by the grain size and the uniformity of the crystallization degree; at the same time, the glass-ceramics also need to have good mechanical properties to meet the mechanical strength requirements of the electronic product cover. The glass-ceramics provided by traditional technologies have the problem of poor overall performance. The optical and mechanical properties are often difficult to meet market requirements, or the cost is high and not suitable for large-scale industrial production. Summary of the Invention

[0003] Based on this, the purpose of this application includes providing a microcrystalline glass and its preparation method, glass products and applications. The microcrystalline glass in this application contains spinel crystal grains and zirconium oxide crystal grains or spodumene crystal grains, which not only have good optical and mechanical properties, but also have low raw material costs and simple preparation process.

[0004] In a first aspect of the present application, a glass-ceramic is provided, wherein the glass-ceramic comprises the following components in terms of weight percentage:

[0005] 35 wt% to 55 wt% SiO2, 20 wt% to 30 wt% Al2O3, 0 wt% to 6 wt% MgO, 0 wt% to 10 wt% ZnO, 0.5 wt% to 3 wt% B2O3, 0 wt% to 3 wt% P2O5, 0 wt% to 3 wt% Li2O, 0 wt% to 6 wt% Na2O, 0 wt% to 6 wt% TiO2, and 0 wt% to 6 wt% ZrO2;

[0006] The glass-ceramics contains a first crystalline phase, the first crystalline phase is a spinel crystalline phase, and the average particle size of the crystal grains of the spinel crystalline phase is 10 nm to 50 nm;

[0007] The glass-ceramics contains a second crystalline phase, the second crystalline phase including at least one of a zirconium oxide crystalline phase and a spodumene crystalline phase; the average particle size of the crystal grains of the second crystalline phase is 20 nm to 50 nm;

[0008] The crystallinity of the glass-ceramics is 25% to 45%.

[0009] In some embodiments, the microcrystalline glass satisfies one or more of the following conditions:

[0010] The ratio of the mass percentage of alumina in the microcrystalline glass to the sum of the mass percentages of magnesium oxide and zinc oxide is 1.67-4.47;

[0011] The ratio of the sum of the mass percentages of zinc oxide and boron oxide in the microcrystalline glass to the sum of the mass percentages of zinc oxide and magnesium oxide is 0.52-1.22;

[0012] The sum of the mass percentages of zirconium oxide and titanium oxide in the microcrystalline glass is 3wt%-6wt%.

[0013] In some embodiments, the microcrystalline glass satisfies one or more of the following conditions:

[0014] The crystallinity of the grains having the spinel crystal phase is 24.6%-43%;

[0015] When the microcrystalline glass contains a lithium feldspar crystal phase, the crystallinity of the grains having the lithium feldspar crystal phase is 0%-0.52%; when the microcrystalline glass contains a zirconia crystal phase, the crystallinity of the grains having the zirconia crystal phase is 0%-10%;

[0016] When the microcrystalline glass contains a zirconia crystal phase, the average grain size of the grains of the zirconia crystal phase is 20nm-50nm;

[0017] When the microcrystalline glass contains a lithium feldspar crystal phase, the average grain size of the grains of the lithium feldspar crystal phase is 20nm-50nm; the spinel crystal phase is selected from at least one crystal phase of zinc aluminum spinel, magnesium aluminum spinel, and magnesium zinc spinel.

[0018] In some embodiments, the microcrystalline glass satisfies one or more of the following conditions:

[0019] The transmittance of the microcrystalline glass to visible light is >88%;

[0020] The haze of the microcrystalline glass is <0.4%;

[0021] The Vickers hardness of the microcrystalline glass is >820kgf / mm 2 .

[0022] The second aspect of the present application provides a preparation method of a microcrystalline glass, comprising the following steps:

[0023] Mixing the raw materials of the microcrystalline glass of the first aspect to prepare a mixture;

[0024] Melting, shaping, and annealing the mixture to prepare a base glass;

[0025] heating the base glass to 800-900℃ for heat preservation treatment for 5-60min, and cooling to obtain the glass-ceramics.

[0026] In some embodiments, the preparation method satisfies one or more of the following conditions:

[0027] In the steps of melting, shaping and annealing the mixture, the melting temperature is 1450-1650℃.

[0028] In the steps of melting, shaping and annealing the mixture, the melting time is 2-10h.

[0029] In some embodiments, the preparation method satisfies one or more of the following conditions:

[0030] In the steps of melting, shaping and annealing the mixture, the annealing temperature is 550-650℃.

[0031] In the steps of melting, shaping and annealing the mixture, the annealing time is 3-5h.

[0032] In some embodiments, in the step of heating and heat preservation treatment of the base glass in the preparation method, the heating rate is 5-20℃ / min.

[0033] In a third aspect, the present application provides a glass product, which comprises the glass-ceramics prepared by the method of the first aspect or the second aspect.

[0034] In a fourth aspect, the present application provides the use of the glass-ceramics prepared by the method of the first aspect or the second aspect in the manufacturing process of electronic devices.

[0035] The glass-ceramics provided in the present application have good optical and mechanical properties, low raw material cost and can be prepared by simple process, by fine adjustment of the main components (low lithium oxide content, suitable relative content of magnesium oxide, zinc oxide and aluminum oxide) in the glass-ceramics, so that the glass-ceramics contain spinel crystal grains and zirconia or spodumene crystal grains, and the crystal grains have small size and low crystallinity.

[0036] The preparation method of the glass-ceramics provided in the present application is simple, compared with the complex process of two-step heat treatment in the traditional technical solution, and only one short-time heat treatment operation is needed after melting and annealing, so that one-step crystallization can be realized and glass-ceramics with good optical and mechanical properties can be obtained.

[0037] The glass product provided in the present application can obtain a glass product with good optical and mechanical properties by using the aforementioned microcrystalline glass, and the cost of the glass product is low.

[0038] The aforementioned microcrystalline glass used in the present application has good optical and mechanical properties, and can be applied to the manufacture or application of electronic devices with high requirements on transmittance, haze and hardness. BRIEF DESCRIPTION OF DRAWINGS

[0039] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings needed to be used in the description of the embodiments or the prior art will be briefly introduced. Obviously, the drawings in the following description are only embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative effort on the basis of the provided drawings.

[0040] Figure 1 X-ray powder diffraction pattern of the microcrystalline glass prepared in Example 19. DETAILED DESCRIPTION

[0041] In order to facilitate the understanding of the present application, the present application will be described more fully below, and preferred embodiments of the present application are given. However, the present application can be realized in many different forms and is not limited to the embodiments described herein. On the contrary, these embodiments are provided to make the disclosure of the present application more thorough and comprehensive.

[0042] The embodiments of the present application will be described in detail below with reference to the accompanying drawings. The present embodiments are implemented on the premise of the technical solutions of the present application, and detailed implementation modes and specific operation processes are given, but the protection scope of the present application is not limited to the following embodiments.

[0043] 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 the present application belongs. The terms used in the specification of the present application are only for the purpose of describing specific embodiments and are not intended to limit the present application.

[0044] Terminology

[0045] Unless otherwise stated or contradictory, the terms or phrases used herein have the following meanings:

[0046] In the present application, "a plurality of", "a plurality of" and the like are used without specific limitation, which means more than two or equal to two in quantity. For example, "one or more" means one or more than two.

[0047] In the present application, "further", "particularly" and the like are used to describe purposes and indicate differences in content, but should not be understood as limiting the scope of protection of the present application.

[0048] In the present application, the technical features described in an open way include both the closed technical solution consisting of the listed features and the open technical solution containing the listed features.

[0049] In the present application, as to the numerical interval (i.e. numerical range), if no special description is provided, the distribution of the optional numerical values in the numerical interval is regarded as continuous, and includes both numerical end points (i.e. minimum value and maximum value) of the numerical interval and each numerical value between the two numerical end points. If no special description is provided, when the numerical interval only points to the integers in the numerical interval, the two end point integers of the numerical range and each integer between the two end points are equivalent to directly listing each integer. When multiple numerical ranges are provided to describe a feature or property, these numerical ranges can be combined. In other words, unless otherwise specified, the numerical range disclosed herein should be understood to include any and all sub-ranges encompassed therein. The "numerical value" in the numerical interval can be any quantitative value, such as a number, a percentage, a ratio, etc. The "numerical interval" is allowed to broadly include numerical interval types such as percentage interval, ratio interval, and value interval.

[0050] In the present application, the term "room temperature" generally refers to 4℃ to 35℃, preferably 20℃±5℃. In some embodiments of the present application, room temperature refers to 20℃ to 30℃.

[0051] In the present application, unless otherwise specified, the temperature parameter allows both constant temperature treatment and variation within a certain temperature interval. It should be understood that the constant temperature treatment allows the temperature to fluctuate within the accuracy range controlled by the instrument. Fluctuation within a range such as ±5℃, ±4℃, ±3℃, ±2℃, ±1℃ is allowed.

[0052] In the present application, if only the unit is provided after the right end point when referring to the unit of the data range, it means that the units of the left end point and the right end point are the same. For example, 2-10h means that the unit of the left end point "2" and the right end point "10" are both h (hour).

[0053] Glass-ceramics, also known as glass ceramics, contains both crystalline and glass phases. It is this multi-phase composition that allows glass-ceramics to possess excellent properties that are difficult to achieve with traditional glass. In particular, the microcrystalline phase in the structure can hinder the propagation path of microcracks, and plays an important role in improving the average hardness, fracture toughness, impact resistance, and drop resistance of the glass. Due to the special structure of glass-ceramics, it has great application prospects in the fields of front or back cover protective glass and optoelectronic glass for electronic devices such as smart displays and mobile devices. The crystalline phase in glass-ceramics can be formed by introducing a nucleating agent into the matrix glass formula or adjusting the oxide ratio composition in the formula, and subsequently heat treating the base glass to form one or more crystalline phases, so that the crystalline phase and the glass phase coexist in the glass body to form a multi-phase crystalline material.

[0054] Traditional microcrystalline glass adopts a lithium aluminum silicon system with a high lithium content, but with the development of the new energy industry, the prices of lithium-containing raw materials such as lithium carbonate and spodumene used in traditional lithium aluminum silicon (LAS) systems have skyrocketed, resulting in a significant increase in production costs. In addition to the cost of raw materials, the lithium aluminum silicon system requires a complex heat treatment process and chemical strengthening method to obtain, which further increases the cost of production. Grains with a spinel phase are also a good choice for the crystalline phase of microcrystalline glass. Spinel is an oxide with a cubic structure with a general chemical formula of AB2O4. The typical A element can be selected from divalent metal ions such as Zn, Fe or Mg with tetrahedral coordination, and the B-position element can be selected from Al, Cr or Fe metal ions with octahedral coordination, belonging to the Fd3m space group. Compared with the scarcity of lithium ore resources, the reserves of sodium and magnesium raw materials used in the magnesium aluminum silicon (MAS) system are much richer and the cost is relatively low.

[0055] In a first aspect of the present application, a glass-ceramic is provided, wherein the glass-ceramic comprises the following components in terms of weight percentage:

[0056] 35wt% to 55wt% SiO2, 20wt% to 30wt% Al2O3, 0wt% to 6wt% MgO, 0wt% to 10wt% ZnO, 0.5wt% to 3wt% B2O3, 0wt% to 3wt% P2O5, 0wt% to 3wt% Li2O, 0wt% to 6wt% Na2O, 0wt% to 6wt% TiO2, and 0wt% to 6wt% ZrO2.

[0057] In some embodiments, the glass-ceramics comprises the following components in terms of mass percentage:

[0058] 35wt%-55wt% of SiO2, 20wt%-30wt% of Al2O3, 0wt%-6wt% of MgO, 0wt%-10wt% of ZnO, 0.5wt%-3wt% of B2O3, 0wt%-3wt% of P2O5, 0wt%-3wt% of Li2O, 0wt%-6wt% of Na2O, 0wt%-6wt% of TiO2, and 0wt%-6wt% of ZrO2;

[0059] The microcrystalline glass comprises a first crystalline phase, the first crystalline phase is a spinel crystalline phase, and the average grain size of the crystal grains of the spinel crystalline phase is 10nm-50nm.

[0060] The microcrystalline glass comprises a second crystalline phase, the second crystalline phase is at least one of a zirconia crystalline phase and a spodumene crystalline phase, and the average grain size of the crystal grains of the second crystalline phase is 20nm-50nm.

[0061] The crystallinity of the microcrystalline glass is 25%-45%.

[0062] The microcrystalline glass provided in the present application is prepared by finely adjusting the main components (the relative contents of magnesium oxide, zinc oxide and aluminum oxide are suitable, and the content of lithium oxide is lower) in the microcrystalline glass, so that the microcrystalline glass comprises crystal grains of a spinel crystalline phase and crystal grains of a zirconia crystalline phase or a spodumene crystalline phase, the grain size is small, the crystallinity of the glass is low, the optical and mechanical properties of the microcrystalline glass are good, the raw material cost is low, and the microcrystalline glass can be prepared by a simple process.

[0063] In some embodiments, the microcrystalline glass contains 35wt%-55wt% of SiO2, further can be 40wt%-55wt%, and can be selected from any one of the following mass percentages or an interval formed by any two of the following mass percentages: 35wt%, 35.5wt%, 36wt%, 37wt%, 38wt%, 39wt%, 40wt%, 41.5wt%, 42.5wt%, 43wt%, 43.5wt%, 44wt%, 44.5wt%, 45wt%, 45.5wt%, 46wt%, 46.5wt%, 47wt%, 47.3wt%, 47.5wt%, 48wt%, 48.5wt%, 49wt%, 49.5wt%, 50wt%, 50.5wt%, 50.8wt%, 51wt%, 51.5wt%, 51.8wt%, 52wt%, 52.5wt%, 53wt%, 54wt%, 54.5wt%, 55wt%, etc. SiO2 is a network former oxide, can form glass alone, and is one of the necessary components, mainly constitutes the network main structure of the base glass and the microcrystalline glass, and gives the base glass and the microcrystalline glass better chemical stability, mechanical properties and forming properties. However, when there is too much SiO2 in the glass system, the glass melting temperature may be increased, and it is difficult to clarify and melt. In the microcrystallization process of the base glass, too high SiO2 promotes the appearance of quartz and quartz solid solution in the glass microcrystallization process.

[0064] In some embodiments, the microcrystalline glass contains 20wt%-30wt% of Al2O3, and further can be selected from any one of the following mass percentages or a range formed by any two of the following mass percentages: 20wt%, 20.5wt%, 21wt%, 21.5wt%, 22wt%, 22.5wt%, 23wt%, 23.5wt%, 24wt%, 24.5wt%, 24.7wt%, 24.8wt%, 25wt%, 25.5wt%, 25.8wt%, 26wt%, 26.5wt%, 26.6wt%, 26.7wt%, 26.8wt%, 27wt%, 27.5wt%, 27.7wt%, 28wt%, 28.5wt%, 28.7wt%, 29wt%, 29.3wt%, 29.5wt%, 29.8wt%, 29.9wt%, etc. Al2O3 is a network intermediate oxide, and non-bridge oxygen forms aluminum-oxygen tetrahedron, which has a larger volume than silicon-oxygen tetrahedron, and generates larger gaps in the glass structure. The glass system containing a suitable content of Al2O3 is beneficial for ion exchange, so that the chemical strengthening effect is better, and the mechanical properties of the glass are improved. Al2O3 is also a component of spinel and spodumene crystal phase, and a suitable content of Al2O3 in the glass system is beneficial for the formation of crystal phase. However, Al2O3 is a very refractory oxide. If the content of Al2O3 in the glass system is too high, the high-temperature viscosity of the glass can be too large, which makes it difficult to clarify and homogenize the glass, and the concentration of bubble defects in the glass increases significantly. Moreover, the glass crystallization temperature is also significantly increased, and the crystallization ability of the base glass is inhibited. If the content of Al2O3 in the glass system is too low, it can be difficult to obtain the required spinel crystal phase.

[0065] In some embodiments, the microcrystalline glass contains 0wt%-6wt% of MgO, further can be 4wt%-6wt%, and can be selected from any one of the following mass percentages or a range formed by any two of the following mass percentages: 0wt%, 0.8wt%, 1wt%, 1.5wt%, 2wt%, 2.2wt%, 2.5wt%, 2.8wt%, 2.9wt%, 3wt%, 3.5wt%, 3.6wt%, 3.7wt%, 3.8wt%, 3.9wt%, 4wt%, 4.2wt%, 4.5wt%, 4.6wt%, 4.7wt%, 4.8wt%, 4.9wt%, 5wt%, 5.2wt%, 5.3wt%, 5.4wt%, 5.5wt%, 5.6wt%, 5.7wt%, 5.8wt%, 5.9wt%, 6wt%, etc. MgO belongs to network modifying oxide, and adding appropriate amount of MgO is conducive to reducing the high-temperature viscosity of the base glass, increasing the diffusion rate of atoms in the glass, promoting the crystallization of the microcrystalline glass, and making the microcrystalline glass have better crystallization effect. It can modify the glass structure, improve the strength and chemical stability of the base glass, and is also a component of spinel phase. If the content of MgO is low, it may be not conducive to the formation of spinel phase crystals, so that the microcrystalline glass is difficult to have good optical and mechanical properties; and if the content of MgO is too high, the high-temperature viscosity of the melt will increase, which will increase the melting difficulty, and may also inhibit the crystallization of the glass, so that the glass cannot be uniformly crystallized.

[0066] In some embodiments, the microcrystalline glass contains 0wt%-10wt% of ZnO, further can be 4wt%-10wt%, and can be selected from any one of the following mass percentages or a range formed by any two of the following mass percentages: 0wt%, 1wt%, 1.5wt%, 2wt%, 2.5wt%, 3wt%, 3.8wt%, 4wt%, 4.8wt%, 4.9wt%, 5.1wt%, 5.5wt%, 5.8wt%, 6wt%, 6.5wt%, 6.7wt%, 6.8wt%, 7wt%, 7.4wt%, 7.5wt%, 7.8wt%, 7.9wt%, 8wt%, 8.4wt%, 8.5wt%, 8.7wt%, 9wt%, 9.2wt%, 9.5wt%, 9.8wt%, 10wt%, etc. ZnO is a network modifier, and the appropriate content of ZnO in the glass system is beneficial to reduce the high-temperature viscosity of the base glass, modify the glass structure, improve the strength and chemical stability of the base glass, and also is a component of spinel phase. ZnO has a positive effect on improving the ion-strengthened layer depth of the glass, improving the ion-strengthening efficiency, strengthening depth, and improving the surface strength of the glass; at the same time, it also improves the chemical stability of the glass and the refractive index of the glass, increases the gloss and transmittance of the glass. Because Zn 2+ In the glass melt, the accumulation of high field strength increases the crystallization tendency of the base glass and reduces the crystallization activation energy of the target phase. If the content of ZnO in the glass system is low, the crystallization activation energy of the glass can be high, which is not conducive to the rapid microcrystallization process of the glass; at the same time, the price of ZnO raw material is relatively high, and when the content of ZnO in the glass system is high, a large amount of ZnO can remain in the glass phase, which can reduce the performance of the glass and also reduce the Li-Na and Na-K ion exchange capacity of the glass-ceramic.

[0067] In some embodiments, the microcrystalline glass contains 0.5wt%-3wt% of B2O3, further can be 1wt%-3wt%, and can be selected from any one of the following mass percentages or a range formed by any two of the following mass percentages: 0.5wt%, 0.7wt%, 1wt%, 1.2wt%, 1.3wt%, 1.5wt%, 1.7wt%, 1.8wt%, 1.9wt%, 2wt%, 2.2wt%, 2.3wt%, 2.4wt%, 2.5wt%, 2.6wt%, 2.7wt%, 2.8wt%, 2.9wt%, 3wt%, etc. B2O3 is a network former oxide, and the appropriate content of B2O3 in the glass system is conducive to reducing the high-temperature melting viscosity of the glass, improving the melting characteristics. Adding an appropriate amount of B2O3 to the base glass is conducive to promoting the phase separation and nucleation and crystallization of the base glass, and reducing the crystallization time of the base glass. When the content of B2O3 is too low, it may not be conducive to promoting the phase separation of the magnesium-aluminum-silicon system, so it is difficult to obtain a microcrystalline glass with good optical and mechanical properties; when the content of B2O3 is too high, the size of the phase separation particles generated after the glass phase separation is large, that is, the average grain size of the crystal grains is large, so the crystal grain size is close to the wavelength of visible light, resulting in a large amount of incident light scattering, so the microcrystalline glass has low visible light transmittance and high haze.

[0068] In some embodiments, the microcrystalline glass contains 0wt%-3wt% of P2O5, further can be 0wt%-2wt%, and can be selected from any one of the following mass percentages or a range formed by any two of the following mass percentages: 0wt%, 0.1wt%, 0.2wt%, 0.3wt%, 0.4wt%, 0.5wt%, 0.6wt%, 0.7wt%, 0.8wt%, 0.9wt%, 1wt%, 1.1wt%, 1.3wt%, 1.4wt%, 1.5wt%, 1.6wt%, 1.7wt%, 1.8wt%, 1.9wt%, 2wt%, 2.2wt%, 2.3wt%, 2.4wt%, 2.5wt%, 2.8wt%, 2.9wt%, 3wt%, etc. P2O5 is a network former oxide in the glass system, and the appropriate content of P2O5 in the glass system is conducive to promoting the phase separation of the glass and thus promoting the effect of crystallization. P2O5 forms a network by connecting [PO4] tetrahedrons to each other, making the glass network structure loose, and the network gap large, which is conducive to ion strengthening in the glass strengthening process and plays an important role in obtaining a high compressive stress layer. If the content of P2O5 in the glass system is too high, it will make it difficult for the base glass to form a stable glass, and the base glass will crystallize, making it difficult to obtain a crystallized glass with high transmittance; it can also cause the fragments to scatter easily when the chemically strengthened glass breaks, and the acid resistance is significantly reduced.

[0069] In some embodiments, the microcrystalline glass includes 0wt% to 3wt% Li2O in terms of mass percentage, and can further be 1wt% to 3wt%, or can be selected from any one of the following mass percentages or an interval consisting of any two mass percentages: 0wt%, 0.5wt%, 1wt%, 1.2wt%, 1.3wt%, 1.5wt%, 1.6wt%, 1.7wt%, 1.8wt%, 1.9wt%, 2wt%, 2.1wt%, 2.2wt%, 2.3wt%, 2.4wt%, 2.5wt%, 2.6wt%, 2.7wt%, 2.8wt%, 2.9wt%, 3wt%, etc. Li2O is a network exogenous oxide. Adding a suitable amount of Li2O to the glass system can reduce the viscosity of the glass, promote the melting and clarification of the glass, and is also beneficial to quickly reduce the crystallization temperature of the glass. Moreover, suitable Li + The content is also conducive to achieving a high depth of ion strengthening in microcrystalline glass. If the Li2O content in the glass is low, it may cause the subsequent chemical strengthening process to react with Na + The mutual reinforcement effect is small, which is not conducive to reducing the cracks on the surface of the crystallized glass and further improving the mechanical strength of the glass; + It also has a strong agglomeration effect, which increases the crystallization ability of the base glass to a certain extent. Therefore, a low Li2O content may not be conducive to further improving the microcrystallization process of the glass. If the Li2O content in the glass is too high, not only will the cost of the glass increase, but it may also cause the viscosity of the glass to be too low, making it difficult to obtain a chemically stable glass composition, resulting in too low a compressive stress value during the ion strengthening process.

[0070] In some embodiments, the microcrystalline glass includes 0wt% to 6wt% Na2O in terms of mass percentage, and can further be 4wt% to 6wt%, or can be selected from any one of the following mass percentages or an interval consisting of any two of the following mass percentages: 0wt%, 0.5wt%, 1wt%, 1.5wt%, 2wt%, 2.5wt%, 2.7wt%, 2.9wt%, 3wt%, 3.8wt%, 3.9wt%, 4wt%, 4.2wt%, 4.3wt%, 4.5wt%, 4.6wt%, 4.8wt%, 5wt%, 5.1wt%, 5.2wt%, 5.5wt%, 5.6wt%, 5.7wt%, 5.8wt%, 5.9wt%, 6wt%, etc. Na2O is a network external oxide. The inclusion of an appropriate amount of Na2O in the glass system can significantly reduce the viscosity of the base glass, promote the melting and clarification of the base glass, and at the same time reduce the glass crystallization temperature, so that the crystallized glass can react with K in the potassium nitrate molten salt. +The ions are intensified to generate high compressive stress on the surface of the glass to improve the strength of the glass. However, if the content of Na2O is too high, the crystallization ability of the glass may be weakened, resulting in an increase in residual glass phase.

[0071] In some embodiments, the microcrystalline glass contains 0wt% to 6wt% of TiO2, further 1wt% to 4wt%, and can be selected from any one of the following mass percentages or an interval formed by any two of the following mass percentages: 0wt%, 0.2wt%, 0.4wt%, 0.5wt%, 1wt%, 1.5wt%, 1.7wt%, 1.9wt%, 2wt%, 2.1wt%, 2.2wt%, 2.5wt%, 2.6wt%, 2.7wt%, 2.8wt%, 2.9wt%, 3wt%, 3.1wt%, 3.2wt%, 3.3wt%, 3.4wt%, 3.5wt%, 3.8wt%, 4wt%, 4.6wt%, 4.7wt%, 5.3wt%, 5.5wt%, 5.7wt%, 6wt%, etc. The appropriate content of TiO2 in the glass system can refine the grain, significantly improve the crystallization ability of the glass, increase the liquidus temperature, promote crystallization, and promote the ion strengthening effect of the glass. However, when the content of TiO2 in the glass system is too high, the glass may have a deep color, and a high content of TiO2 may also make it difficult to control the growth of the crystal phase in the base glass, and the abnormal growth of the crystal phase may generate more impurities, making it difficult to control the performance of the glass ceramic, and causing cracking and a significant decrease in performance.

[0072] In some embodiments, the microcrystalline glass contains 0wt% to 6wt% of ZrO2, further can be 1wt% to 4wt%, and can be selected from any one of the following mass percentages or a range formed by any two of the following mass percentages: 0wt%, 0.1wt%, 0.5wt%, 0.7wt%, 0.9wt%, 1wt%, 1.1wt%, 1.3wt%, 1.4wt%, 1.5wt%, 1.7wt%, 1.8wt%, 2wt%, 2.1wt%, 2.3wt%, 2.4wt%, 2.5wt%, 2.6wt%, 2.8wt%, 3wt%, 3.1wt%, 3.2wt%, 3.5wt%, 3.8wt%, 3.9wt%, 4wt%, 4.2wt%, 4.5wt%, 4.8wt%, 5wt%, 5.5wt%, 6wt%, etc. The appropriate content of ZrO2 in the glass system helps to reduce the grain size during crystallization, and obtain microcrystalline glass with higher transparency; the ZrO2 ion has high potential energy, and the appropriate content of ZrO2 in the glass system can also enhance the glass network structure, improve the chemical stability, fracture toughness and bending strength of the glass. If the content of ZrO2 in the glass system is too high, the solubility of ZrO2 in the glass body is low, which may cause the melting temperature of the glass substrate to increase significantly, and also may cause more ZrO2 non-melting substances to remain in the glass, thereby causing the glass to be unable to crystallize uniformly.

[0073] In some embodiments, the ratio of the mass percentage of alumina to the sum of the mass percentages of magnesium oxide and zinc oxide in the microcrystalline glass is 1.67 to 4.47, further can be 1.68 to 4.42, and can be selected from any one of the following ratios or a range formed by any two of the following ratios: 1.68, 1.74, 1.81, 1.82, 1.83, 1.89, 1.9, 1.92, 1.95, 1.96, 1.97, 1.99, 2.05, 2.11, 2.2, 2.21, 2.23, 2.24, 2.25, 2.27, 2.39, 2.46, 2.5, 2.56, 2.61, 2.67, 2.71, 2.73, 2.77, 3.11, 3.16, 3.22, 3.38, 3.5, 3.59, 3.73, 3.88, 4.18, 4.33, 4.35, 4.42, etc. Spinel is an oxide with cubic structure, and its chemical formula is AB2O4, wherein A is a divalent metal ion such as Mg and Zn with tetrahedral coordination, and B is an Al metal ion with octahedral coordination. Therefore, Al2O3, MgO and ZnO are the components of magnesium aluminum spinel and magnesium zinc spinel crystal phase, and their proportions affect the proportion of the crystal phase generated by the base glass. Too low a proportion makes it difficult to generate target crystal phase, too many impurities, and the performance is difficult to control. Too high a proportion causes a large amount of MgO and ZnO to remain in the glass phase, affecting the performance of the glass.

[0074] In some embodiments, the ratio of the sum of the mass percentage of zinc oxide and boron oxide to the sum of the mass percentage of zinc oxide and magnesium oxide in the glass-ceramic is 0.52-1.22, further can be 0.55-1.22, and can be selected from any one of the following ratios or an interval formed by any two of the following ratios: 0.55, 0.57, 0.62, 0.63, 0.67, 0.68, 0.7, 0.71, 0.75, 0.76, 0.77, 0.79, 0.8, 0.81, 0.82, 0.83, 0.84, 0.85, 0.86, 0.87, 0.92, 0.94, 0.97, 1, 1.01, 1.03, 1.1, 1.15, 1.21, 1.22, etc. The inventors of the present application found that when the ratio is too low, the hardness of the glass is reduced, and when the ratio is too high, the crystallization effect is affected.

[0075] In some embodiments, the sum of the mass percentage of zirconium oxide and titanium oxide in the glass-ceramic is 3wt%-6wt%, and can be selected from any one of the following mass percentages or an interval formed by any two of the following mass percentages: 3, 3.5, 4, 4.3, 4.5, 4.6, 4.7, 4.8, 4.9, 5, 5.2, 5.3, 5.4, 5.5, 5.7, 5.8, 5.9, 6, etc. Both ZrO2 and TiO2 are nucleating agents, and as a composite crystal nucleating agent, they can promote the formation of a large number of microcrystals under low temperature conditions. If the sum of the mass percentages of the two is too low, the overall crystallization ability of the base glass is poor, the crystallinity is low, and the mechanical properties are poor. If the sum of the mass percentages of the two is too high, it is difficult to control the crystallization process, and the transmittance is low.

[0076] In some embodiments, the grain size of the spinel crystal phase in the glass-ceramic is ≤50nm.

[0077] In some embodiments, the spinel crystal phase in the glass-ceramic is selected from at least one of the following crystal phases: zinc aluminum spinel, magnesium aluminum spinel, and magnesium zinc spinel.

[0078] In some embodiments, the microcrystalline glass contains a spinel crystal phase, and the average grain size of the spinel crystal phase is 10-50 nm, further can be 14-50 nm, more further can be 30-45 nm, and can be selected from any one of the following average grain size values or a range formed by two average grain size values: 14 nm, 16 nm, 17 nm, 18 nm, 19 nm, 20 nm, 23 nm, 24 nm, 25 nm, 26 nm, 27 nm, 28 nm, 30 nm, 31 nm, 34 nm, 35 nm, 36 nm, 37 nm, 39 nm, 42 nm, 43 nm, 45 nm, 46 nm, 48 nm, 50 nm, etc. In some embodiments, the microcrystalline glass contains at least one of a zirconia crystal phase and a spodumene crystal phase.

[0079] In some embodiments, when the microcrystalline glass contains a zirconia crystal phase, the average grain size of the zirconia crystal phase is 20-50 nm, further can be 25-45 nm, more further can be 35-45 nm, and can be selected from any one of the following average grain size values or a range formed by two average grain size values: 20 nm, 21 nm, 22 nm, 23 nm, 24 nm, 25 nm, 26 nm, 27 nm, 28 nm, 29 nm, 30 nm, 31 nm, 32 nm, 33 nm, 34 nm, 35 nm, 36 nm, 37 nm, 38 nm, 39 nm, 40 nm, 41 nm, 42 nm, 43 nm, 44 nm, 45 nm, 46 nm, 47 nm, 48 nm, 49 nm, 50 nm, etc.

[0080] In some embodiments, when the microcrystalline glass contains a spodumene crystal phase, the average grain size of the spodumene crystal phase is 20-50 nm, further can be 25-45 nm, more further can be 35-45 nm, and can be selected from any one of the following average grain size values or a range formed by two average grain size values: 20 nm, 21 nm, 22 nm, 23 nm, 24 nm, 25 nm, 26 nm, 27 nm, 28 nm, 29 nm, 30 nm, 31 nm, 32 nm, 33 nm, 34 nm, 35 nm, 36 nm, 37 nm, 38 nm, 39 nm, 40 nm, 41 nm, 42 nm, 43 nm, 44 nm, 45 nm, 46 nm, 47 nm, 48 nm, 49 nm, 50 nm, etc.

[0081] In some embodiments, the total crystallinity of the glass-ceramic is 25% to 45%, further can be 25.08% to 44.86%, and can be selected from any one of the following crystallinities or a range defined by any two of the following crystallinities: 25%, 25.08%, 25.2%, 25.43%, 25.61%, 25.62%, 25.94%, 25.95%, 25.97%, 26.1%, 26.57%, 26.59%, 26.73%, 27.2%, 28.28%, 30%, 30.39%, 30.4%, 30.9%, 30.97%, 31.08%, 31.49%, 32.04%, 32.9%, 32.99%, 33.7%, 34.61%, 34.86%, 35%, 35.07%, 35.22%, 36.6%, 36.91%, 37.36%, 37.68%, 38.1%, 39.26%, 39.45%, 39.55%, 39.73%, 40%, 40.32%, 42.17%, 42.81%, 43.02%, 43.06%, 44.01%, 44.86%, 45%, etc. The glass-ceramic has a suitable crystallinity, which is beneficial to improve the transmittance of the glass-ceramic. Specifically, when the grain size is less than the wavelength of visible light, the glass-ceramic has a lower optical scattering and a high transmittance. Controlling the size of the precipitated grains is the key to improving the transmittance of the glass-ceramic. It is generally believed in the art that the preparation of a high-crystallinity high-transmittance glass-ceramic is difficult.

[0082] In some embodiments, when the glass-ceramic contains a zirconia crystal phase, the crystallinity of the grains having the zirconia crystal phase is 0% to 10%, and can be selected from any one of the following crystallinities or a range defined by any two of the following crystallinities: 1.32%, 0%, 0.21%, 1.08%, 1.27%, 1.4%, 1.97%, 2.1%, 2.16%, 2.26%, 2.68%, 2.7%, 2.8%, 3%, 3.26%, 3.48%, 3.56%, 3.8%, 3.88%, 3.91%, 4.06%, 4.2%, 4.34%, 4.47%, 4.8%, 4.93%, 4.97%, 5.2%, 5.27%, 5.28%, 5.54%, 5.6%, 5.67%, 5.7%, 5.79%, 5.94%, 6.08%, 6.16%, 6.22%, 6.44%, 6.46%, 6.77%, 6.82%, 7.02%, 9.24%, etc. Controlling the crystallinity of the zirconia in the glass-ceramic within a suitable range is more beneficial to obtain a higher transmittance, because when the size of the zirconia grains is large, the high crystallinity leads to a decrease in the transmittance of the glass-ceramic.

[0083] In some embodiments, the crystallinity of the grains having the spinel crystal phase is 24.6% to 43%, and can be selected from any one of the following or a range defined by any two of the following: 42.66%, 24.6%, 24.8%, 24.96%, 25.2%, 25.3%, 25.46%, 25.5%, 25.52%, 25.6%, 25.81%, 26.1%, 26.26%, 27.2%, 28%, 29.22%, 30.07%, 30.1%, 30.56%, 30.6%, 30.8%, 31.03%, 31.75%, 32.7%, 32.77%, 33.35%, 34.2%, 34.53%, 34.8%, 36.45%, 36.5%, 36.88%, 37.31%, 37.63%, 38.75%, 39%, 39.15%, 39.36%, 39.9%, 41.12%, 41.47%, 41.7%, 42.34%, 42.84%, etc.

[0084] In some embodiments, the crystallinity of the grains having the spodumene crystal phase is 0% to 0.52%, and can be selected from any one of the following or a range defined by any two of the following: 0%, 0.1%, 0.2%, 0.22%, 0.27%, 0.28%, 0.29%, 0.3%, 0.31%, 0.32%, 0.34%, 0.35%, 0.37%, 0.4%, 0.41%, 0.42%, 0.44%, 0.45%, 0.46%, 0.47%, 0.48%, 0.49%, 0.5%, 0.51%, 0.52%, etc. Controlling the crystallinity of spodumene in the glass-ceramic within a suitable range is more conducive to obtaining a higher transmittance, because when the spodumene grain size is large, too high crystallinity results in a decrease in the transmittance of the glass-ceramic.

[0085] In some embodiments, the microcrystalline glass contains spinel crystal phase, and the crystallinity of the spinel crystal phase is 24.6% to 44.37%, and can be selected from any one of the following or an interval formed by any two of the following: 24.6%, 24.8%, 24.96%, 25.2%, 25.3%, 25.46%, 25.5%, 25.52%, 25.6%, 25.81%, 26.1%, 26.26%, 27.2%, 28%, 30.07%, 30.1%, 30.56%, 30.6%, 30.8%, 31.03%, 31.75%, 32.7%, 32.77%, 33.35%, 34.2%, 34.53%, 34.8%, 36.45%, 36.5%, 36.88%, 37.31%, 37.63%, 38.75%, 39%, 39.15%, 39.36%, 39.9%, 41.7%, 42.34%, 42.61%, 42.66%, 43.5%, 44.37%, etc.

[0086] In some embodiments, the microcrystalline glass has a visible light transmittance of > 88%, and can be 88% to 92%, and can be selected from any one of the following or an interval formed by any two of the following: 88.02%, 88.14%, 88.23%, 88.26%, 88.28%, 88.56%, 88.57%, 88.67%, 88.69%, 88.72%, 88.76%, 88.78%, 88.84%, 88.85%, 88.87%, 88.92%, 88.93%, 88.96%, 89.01%, 89.02%, 89.03%, 89.04%, 89.05%, 89.08%, 89.13%, 89.17%, 89.22%, 89.24%, 89.26%, 89.34%, 89.38%, 89.39%, 89.41%, 89.57%, 90.02%, 90.62%, 91.85%, etc.

[0087] In some embodiments, the microcrystalline glass has a haze of < 0.4%, and can be 0.1% to 0.4%, and can be selected from any one of the following or an interval formed by any two of the following: 0.1%, 0.12%, 0.13%, 0.16%, 0.17%, 0.18%, 0.19%, 0.2%, 0.21%, 0.22%, 0.24%, 0.25%, 0.26%, 0.27%, 0.28%, 0.29%, 0.31%, 0.32%, 0.33%, 0.35%, 0.36%, 0.38%, etc.

[0088] In some embodiments, the microcrystalline glass has a Vickers hardness of > 820 kgf / mm 2, further can be 820kgf / mm 2 ~837kgf / mm 2 , further can be selected from any one of the following Vickers hardness values or the interval consisting of two Vickers hardness values: 820kgf / mm 2 , 821kgf / mm 2 , 822kgf / mm 2 , 823kgf / mm 2 , 824kgf / mm 2 , 825kgf / mm 2 , 826kgf / mm 2 , 827kgf / mm 2 , 828kgf / mm 2 , 829kgf / mm 2 , 830kgf / mm 2 , 831kgf / mm 2 , 832kgf / mm 2 , 833kgf / mm 2 , 834kgf / mm 2 , 836kgf / mm 2 , 837kgf / mm 2 , etc.

[0089] In the present application, unless otherwise specified, the surface Vickers hardness is tested by FALCON400 hardness tester of Netherland HviNOR, and the transmittance in the wavelength range of 380-780nm is tested by Lambda950 UV-Vis spectrophotometer of American PerkinElmer company. The haze of the sample is tested by SUGA optical HZ-V3 haze meter.

[0090] In addition to the composition of the glass, the heat treatment process of the glass can also affect the performance of the glass. Since electronic products have high requirements on the transparency of the cover glass, the microcrystalline glass selected must have high transmittance. The transmittance of the microcrystalline glass is affected by the grain size and the uniformity of crystallization, and the grain size and the uniformity of crystallization are related to the heat treatment process. A suitable heat treatment temperature schedule can also avoid problems such as devitrification of the glass, partial devitrification of the glass, uncrystallization of the glass, and fogging of the glass.

[0091] In the conventional technology, in order to obtain a microcrystalline glass with good optical and mechanical properties, a two-step heat treatment is often performed on the glass substrate, for example, first heat preservation at a nucleation temperature for a period of time and then heat preservation at a crystallization temperature. Through a long time and complex crystallization heat treatment, the target crystal phase slowly nucleates and grows in the substrate glass, and then a microcrystalline glass with the target crystal phase is obtained. However, the two-step method is complicated, has high preparation cost (energy consumption, equipment), high time cost, and great difficulty in controlling the crystallization process, and has natural disadvantages in industrialization.

[0092] In a second aspect of the present application, a preparation method of the microcrystalline glass is provided, comprising the following steps:

[0093] S100: mixing the raw materials of the microcrystalline glass of the first aspect to prepare a mixture;

[0094] S200: melting, shaping and annealing the mixture to prepare a base glass;

[0095] S300: crystallizing and cooling the base glass to obtain the microcrystalline glass.

[0096] In some embodiments, the crystallization temperature is 800-900℃, and can also be selected from any one of the following temperatures or an interval formed by any two of the following temperatures: 800℃, 805℃, 810℃, 815℃, 820℃, 825℃, 830℃, 835℃, 840℃, 845℃, 850℃, 855℃, 860℃, 865℃, 870℃, 875℃, 880℃, 885℃, 895℃, 900℃, etc. A suitable crystallization temperature is conducive to controlling the grain growth. If the crystallization temperature is too low, the crystallinity may be low and the mechanical properties may be poor; if the crystallization temperature is too high, the transmittance may be low.

[0097] In some embodiments, the crystallization time is 5-60min, and can also be selected from any one of the following times or an interval formed by any two of the following times: 5min, 10min, 15min, 20min, 25min, 30min, 35min, 40min, 45min, 50min, 55min, 60min, etc. A suitable crystallization time is conducive to controlling the grain growth. If the crystallization time is too low, the grain size may be small and the mechanical properties may be poor; if the crystallization time is too high, the grains may grow excessively and the transmittance may be low.

[0098] In some embodiments, in the preparation method, the step S300 comprises the following steps: heating and heat preservation of the base glass, and cooling to obtain the microcrystalline glass.

[0099] In some embodiments, in the step of heating and heat-soaking the base glass, the heating rate is 5-20℃ / min, and can also be selected from any one of the following heating rates or a range formed by any two of the following heating rates: 5℃ / min, 6℃ / min, 7℃ / min, 8℃ / min, 9℃ / min, 10℃ / min, 11℃ / min, 12℃ / min, 13℃ / min, 14℃ / min, 15℃ / min, 16℃ / min, 17℃ / min, 18℃ / min, 19℃ / min, 20℃ / min, etc. A suitable heating rate is conducive to controlling grain growth. If the heating rate is too low, the grain size can be small and the mechanical properties can be poor; if the heating rate is too high, the grains can grow excessively and the transmittance can be low.

[0100] The heat treatment process can affect the structure of the glass-ceramic, and when the heat treatment temperature regime is unreasonable, defects such as devitrification, partial devitrification, uncrystallization, poor uniformity of purification, and glass fogging can occur. In the traditional technology, in order to ensure high transmittance, the base glass is often heat-treated by a two-step method, i.e., first heat-soaked at a nucleation temperature for a period of time and then heat-soaked at a crystallization temperature. By means of long-time and complex crystallization heat treatment, the target crystal phase slowly nucleates and grows in the base glass, and a glass-ceramic with the target crystal phase is obtained. However, the two-step method is complicated, has high preparation cost (energy consumption, equipment), high time cost, and great difficulty in controlling the crystallization process, and has natural disadvantages in industrialization.

[0101] In some embodiments, the preparation method comprises the following steps:

[0102] S100: mixing the raw materials of the glass-ceramic of the first aspect to prepare a mixture;

[0103] S200: melting, shaping, and annealing the mixture to prepare a base glass;

[0104] S300: heating the base glass to 800-900℃ for heat-soaking for 5-60min and cooling to obtain the glass-ceramic.

[0105] The preparation method of the glass-ceramic provided in the present application is simple, and compared with the complex process of the two-step heat treatment method in the traditional technical solution, only one short-time heat treatment operation is needed after melting and annealing, i.e., one-step crystallization can be realized, and a glass-ceramic with good optical properties and mechanical properties can be obtained.

[0106] In some embodiments, in step S300, the base glass is heated to 780-900℃; the holding treatment of this step is the crystallization treatment, the heating temperature is the crystallization temperature, and the crystallization temperature can also be selected from any one of the following values or an interval formed by any two of the following values: 780℃, 800℃, 805℃, 810℃, 815℃, 820℃, 825℃, 830℃, 835℃, 840℃, 845℃, 850℃, 855℃, 860℃, 865℃, 870℃, 875℃, 880℃, 885℃, 895℃, 900℃, etc.

[0107] In some embodiments, in step S300, the base glass is heated to 780-900℃ for a holding treatment of 5-60 min; the time of the crystallization treatment can also be selected from any one of the following values or an interval formed by any two of the following values: 20 min, 5 min, 10 min, 15 min, 25 min, 30 min, 35 min, 40 min, 45 min, 50 min, 55 min, 60 min, etc.

[0108] In some embodiments, in step S300, the base glass is heated to 780-900℃ for a holding treatment, and the heating rate is 5-20℃ / min; the heating rate can also be selected from any one of the following values or an interval formed by any two of the following values: 5℃ / min, 6℃ / min, 7℃ / min, 8℃ / min, 9℃ / min, 10℃ / min, 11℃ / min, 12℃ / min, 13℃ / min, 14℃ / min, 15℃ / min, 16℃ / min, 17℃ / min, 18℃ / min, 19℃ / min, 20℃ / min, etc.

[0109] In some embodiments, in the steps of melting, shaping, and annealing the mixture, the melting temperature is 1450-1650℃; the melting temperature can also be selected from any one of the following temperatures or an interval formed by any two of the following temperatures: 1450℃, 1460℃, 1470℃, 1480℃, 1490℃, 1500℃, 1510℃, 1520℃, 1530℃, 1540℃, 1550℃, 1560℃, 1570℃, 1580℃, 1590℃, 1600℃, 1610℃, 1620℃, 1630℃, 1640℃, 1650℃, etc.

[0110] In some embodiments, in the steps of melting, shaping, and annealing the mixture, the melting time is 2-10h; the melting time can also be selected from any one of the following times or an interval formed by any two of the following times: 2h, 3h, 4h, 5h, 6h, 7h, 8h, 9h, 10h, etc.

[0111] In some embodiments, in the step of subjecting the mixture to melting, shaping and annealing, the annealing temperature is 550-650 DEG C, and can be selected from any one of the following temperatures or a range formed by any two of the following temperatures: 550 DEG C, 560 DEG C, 570 DEG C, 580 DEG C, 590 DEG C, 600 DEG C, 610 DEG C, 620 DEG C, 630 DEG C, 640 DEG C, 650 DEG C, etc.

[0112] In some embodiments, in the step of subjecting the mixture to melting, shaping and annealing, the annealing time is 3-5 h, and can be selected from any one of the following times or a range formed by any two of the following times: 3 h, 4 h, 5 h, etc.

[0113] In some embodiments, the preparation method comprises the following steps:

[0114] S100: mixing the glass-ceramic raw materials to prepare a mixture;

[0115] S200: subjecting the mixture to melting at 1450-1650 DEG C for 2-10 h to obtain a glass liquid, shaping the glass liquid, and subjecting to annealing at 550-650 DEG C for 3-5 h to obtain a base glass;

[0116] S300: heating the base glass to 800-900 DEG C at a heating rate of 5-20 DEG C / min, subjecting to holding for 5-60 min, and cooling to obtain the glass-ceramic.

[0117] In a third aspect, the present application provides a glass product comprising the glass-ceramic of the first aspect or the glass-ceramic prepared by the method of the second aspect.

[0118] The glass product provided in the present application utilizes the aforementioned glass-ceramic, and can obtain a glass product with good optical and mechanical properties, and the cost of the glass product is low.

[0119] In a fourth aspect, the present application provides the use of the glass-ceramic of the first aspect or the glass-ceramic prepared by the method of the second aspect in the manufacturing process of electronic devices.

[0120] The aforementioned glass-ceramic used in the present application has good optical and mechanical properties, and can be applied to the manufacturing or application requirements of electronic devices with high requirements on transmittance, haze and hardness, etc.

[0121] In a fifth aspect, the present application provides an electronic device comprising the glass-ceramic of the first aspect or the glass-ceramic prepared by the method of the second aspect.

[0122] The electronic device provided by the application adopts microcrystalline glass with excellent optical and mechanical properties, thereby meeting higher application requirements, such as the high transmittance and anti-falling requirements of cover glass of photoelectric display devices.

[0123] In order to make the application more easily understood and implemented, the following more specific and detailed examples and comparative examples are provided as references.

[0124] The concept, specific examples and resulting technical effects of the application will be further described below with reference to the accompanying drawings, so as to fully understand the application. The purpose of providing these descriptions is only to help explain the application, and should not be used to limit the scope of the claims of the application.

[0125] Unless otherwise specified, the raw materials used in the following tests can be purchased from the market.

[0126] Example 1

[0127] According to Table 1, after mixing all the raw materials, melting at 1450-1650℃ for 2-10h, forming the obtained glass liquid, annealing at 550-650℃ for 4h to obtain the base glass. Heating to 800-900℃ at a heating rate of 5-20℃ / min and keeping for 5-60min, and finally cooling to room temperature to prepare the microcrystalline glass (the specific process parameters can be referred to the data in Table 1 corresponding to the examples). The microcrystalline glass sample is cut into a glass sheet of 50×50×0.7mm by a STX-1203 wire cutting machine of Shenyang Kejing, and then thinned and polished by an HD-640-5L double-sided grinding and polishing machine of Shenzhen Haidel, and finally edge polished by a CNC. The XRD spectrum of the microcrystalline glass sample is tested by X-ray powder diffraction method, and the overall crystallinity and crystallinity of different crystal phases of the microcrystalline glass, as well as the average grain size of different crystal phases are calculated. The surface Vickers hardness is tested by a FALCON400 hardness tester of Yonox, the Netherlands, the transmittance in the wavelength range of 380-780nm is tested by a Lambda950 ultraviolet-visible light spectrophotometer of PerkinElmer, USA, and the haze of the sample is tested by a SUGA optical HZ-V3 haze meter.

[0128] Examples 2-45

[0129] According to Tables 1 to 5, all raw materials are mixed and melted at 1450-1650°C for 2-10 hours, the obtained glass liquid is formed, and annealed at 550-650°C for 4 hours to obtain basic glass. Heat to 800-900°C at a heating rate of 5-20°C / min (preferably 10-20°C / min) and keep warm for 5-60 minutes, and finally cool to room temperature to prepare microcrystalline glass (for specific process parameters, please refer to the data in Tables 1 to 5 corresponding to the examples). The microcrystalline glass samples are cut, ground, polished and edged in the same manner as in Example 1; and characterized and tested in the same manner as in Example 1.

[0130] The glass-ceramics prepared in Examples 1 to 45 have an average visible light transmittance of >88% and a haze of <0.4% after a crystallization treatment at 800 to 900°C for 5 to 60 minutes. The glass-ceramics contain a spinel crystal phase (at least one of zinc-aluminum spinel, magnesium-aluminum spinel, and magnesium-zinc spinel) and at least one of zirconium oxide and spodumene. The crystals in the glass-ceramics grow uniformly, the average grain size of the crystalline phase is <50 nm, the total crystallinity is 25% to 45%, the spodumene crystallinity is <0.5%, and the Vickers hardness is >820 kgf / mm 2 .

[0131] Figure 1 This is the powder X-ray diffraction pattern of the glass-ceramics produced in Example 19. It can be seen that the glass-ceramics contain spinel and ZrO2 crystalline phases. Calculations show that the total crystallinity of the glass-ceramics is 37.36%, the spinel crystallinity is 36.88%, and the spodumene crystallinity is 0.48%. The average particle size of the spinel crystals is 16 nm, while the average particle size of the spodumene crystals is 21 nm.

[0132] The composition of the glass-ceramics produced in Example 46 was identical to that of the glass-ceramics in Example 19, but some of its properties had undergone significant changes. For example, the Vickers hardness of Example 46 decreased, and the crystallinity of the spodumene in the glass-ceramics increased slightly. This indicates that the specific parameters of the glass-ceramics preparation process have a certain impact on the properties of the resulting glass-ceramics.

[0133] Table 1 Glass composition, process parameters and performance parameters of Examples 1 to 10

[0134]

[0135]

[0136] Table 2 Glass composition, process parameters and performance parameters of Examples 11 to 20

[0137]

[0138]

[0139] Glass compositions, process parameters and performance parameters of Examples 21-30

[0140]

[0141]

[0142] Glass compositions, process parameters and performance parameters of Examples 31-40

[0143]

[0144]

[0145] Glass compositions, process parameters and performance parameters of Examples 41-45

[0146]

[0147]

[0148] Comparative Examples 1-6

[0149] According to Table 6, after mixing all raw materials, melting at 1450-1650°C for 2-10h, forming the obtained glass liquid, annealing at 550-650°C for 4h to obtain base glass. Heating at a rate of 5-20°C / min to 800-900°C and holding for 5-60min, and finally cooling to room temperature to prepare the glass-ceramics (for specific process parameters, see Table 1 corresponding to the examples). The glass-ceramic samples were cut into 50x50x0.7mm glass sheets by Shenyang Kejing's STX-1203 wire cutting machine, thinned and polished by Shenzhen Haid's HD-640-5L double-sided grinding and polishing machine, and then CNC edge grinding. The XRD spectrum of the glass-ceramic sample was tested by X-ray powder diffraction method, and the overall crystallinity and crystallinity of different crystal phases of the glass-ceramic were calculated, as well as the average grain size of different crystal phases. The surface Vickers hardness was tested by FALCON400 hardness tester of Yonox, Netherlands, and the transmittance in the wavelength range of 380-780nm was tested by Lambda950 ultraviolet-visible spectrophotometer of PerkinElmer, USA. The sample haze was tested by SUGA optical HZ-V3 haze meter.

[0150] From Table 6, compared with the performance of the glass-ceramics in Examples 1-45:

[0151] The microcrystalline glass prepared in Comparative Example 1 has a lower visible light transmittance (67.73%) and a higher haze (2.41%), which is probably due to the higher content of zirconia in Comparative Example 1. When the content of zirconia and titania as a composite nucleating agent is too high, the crystallization process is difficult to control, resulting in a lower transmittance. As can also be seen from the crystallinity, when the content of zirconia is higher, the crystallinity is larger (10.22%), the average particle size of spodumene is larger, and the optical performance is decreased.

[0152] The microcrystalline glass prepared in Comparative Example 2 has a slightly lower visible light transmittance (78.44%), a slightly higher haze (0.54%) and a slightly lower Vickers hardness (734 kgf / mm 2 ), which is probably due to the slightly higher mass percentage of magnesium oxide (8%) in Comparative Example 2. A higher content of magnesium oxide has a certain inhibitory effect on the crystallization of the glass, which causes the uniformity of glass crystallization to decrease, and the average particle size of lithium spodumene grains in the microcrystalline glass to be slightly higher (52 nm). The glass composition of Comparative Example 2 does not contain boron oxide, and the ratio of the sum of the mass percentages of zinc oxide and boron oxide to the sum of the mass percentages of zinc oxide and magnesium oxide is too low, which reduces the hardness of the glass and is not conducive to the phase separation of the magnesium-aluminum-silicon system, ultimately resulting in the microcrystalline glass prepared in Comparative Example 2 being slightly worse than the microcrystalline glasses in Examples 1-45.

[0153] The optical performance of the microcrystalline glass prepared in Comparative Example 3 is suitable, but the Vickers hardness is lower (698 kgf / mm 2 ), which is probably due to the lower total crystallinity of the microcrystalline glass, the lower crystallinity of spinel, the higher content of aluminum oxide and the higher mass ratio of magnesium oxide and zinc oxide, which causes a large amount of MgO and ZnO to remain in the glass phase, affecting the performance of the glass.

[0154] Table 6 Glass composition, process parameters and performance parameters of Comparative Examples 1-3

[0155]

[0156] The above describes the preferred embodiments of the present application in detail. It should be understood that those skilled in the art can make many modifications and changes without creative labor based on the concept of the present application. Therefore, any technical solutions obtained by logical analysis, reasoning or limited experiments based on the prior art within the concept of the present application should be within the protection scope determined by the claims.

[0157] The technical features of the above-described embodiments can be combined arbitrarily. In order to make the description concise, not all possible combinations of the technical features in the above-described embodiments are described, however, as long as the combinations of the technical features do not exist contradictory, they should be considered as the scope of the present disclosure.

[0158] The above-described embodiments are merely illustrative of several embodiments of the present application, which are described in more detail and in a specific manner, but should not be construed as limiting the scope of the patent. It should be noted that, for those skilled in the art, several modifications and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent of the present application should be subject to the appended claims, and the description and drawings can be used to explain the content of the claims.

Claims

1. A microcrystalline glass, characterized in that, According to the mass percentage, the glass-ceramics comprises the following composition: 47.3wt%-48wt% of SiO2, 27.7wt%-28.5wt% of Al2O3, 5.3wt%-5.5wt% of MgO, 5.8wt%-6.5wt% of ZnO, 1.5wt%-1.8wt% of B2O3, 1wt%-1.3wt% of P2O5, 2.3wt%-2.5wt% of Li2O, 1.5wt%-2.5wt% of Na2O, 1.5wt%-1.9wt% of TiO2, and 4wt%-4.5wt% of ZrO2; The glass-ceramics comprises a first crystalline phase, the first crystalline phase is a spinel crystalline phase, the average grain size of the spinel crystalline phase is 14nm-20nm; the crystallinity of the spinel crystalline phase is 30.8%-36.5%; The glass-ceramics comprises a second crystalline phase, the second crystalline phase comprises a zirconia crystalline phase and a spodumene crystalline phase; the average grain size of the second crystalline phase is 20nm-50nm; The crystallinity of the spodumene crystalline phase is 0.1%-0.52%; The crystallinity of the zirconia crystalline phase is 5.6%-6.82%; The crystallinity of the glass-ceramics is 38.1%-42.81%; The ratio of the mass percentage of alumina in the glass-ceramics to the sum of the mass percentages of magnesium oxide and zinc oxide is 2.39-2.5; The ratio of the sum of the mass percentages of zinc oxide and boron oxide in the glass-ceramics to the sum of the mass percentages of zinc oxide and magnesium oxide is 0.63-0.7; The sum of the mass percentages of zirconia and titanium oxide in the glass-ceramics is 5.5wt%-6wt%; The preparation method of the glass-ceramics comprises the following steps: Mixing the raw materials of the glass-ceramics according to the mass percentage to prepare a mixture; Melting, forming and annealing the mixture to prepare a base glass; Heating the base glass to 800-900℃ for heat preservation for 5-60min, and then cooling to obtain the glass-ceramics; The melting temperature is 1450-1650℃; the annealing temperature is 550-650℃.

2. The glass-ceramic according to claim 1, characterized in that, One or more of the following conditions are met: When the glass-ceramics comprises a zirconia crystalline phase, the average grain size of the zirconia crystalline phase is 20nm-50nm; When the glass-ceramics comprises a spodumene crystalline phase, the average grain size of the spodumene crystalline phase is 20nm-50nm; The spinel crystalline phase is selected from at least one of zinc aluminum spinel, magnesium aluminum spinel and magnesium zinc spinel.

3. The glass-ceramic according to claim 1, characterized in that, 47.5wt% of SiO2, 28wt% of Al2O3, 5.4wt% of MgO, 6wt% of ZnO, 1.7wt% of B2O3, 1.1wt% of P2O5, 2.4wt% of Li2O, 2wt% of Na2O, 1.7wt% of TiO2, and 4.2wt% of ZrO2; The microcrystalline glass comprises a first crystalline phase, the first crystalline phase is a spinel crystalline phase, the average grain size of the spinel crystalline phase is 17 nm; the crystallinity of the spinel crystalline phase is 34.2%; The microcrystalline glass comprises a second crystalline phase, the second crystalline phase comprises a zirconia crystalline phase and a spodumene crystalline phase; the average grain size of the second crystalline phase is 20 nm to 50 nm; When the microcrystalline glass comprises a spodumene crystalline phase, the average grain size of the spodumene crystalline phase is 25 nm; The crystallinity of the spodumene crystalline phase is 0.41%; When the microcrystalline glass comprises a zirconia crystalline phase, the average grain size of the zirconia crystalline phase is 22 nm; the crystallinity of the zirconia crystalline phase is 6.22%; The crystallinity of the microcrystalline glass is 40.83%; The ratio of the mass percentage content of aluminum oxide in the microcrystalline glass to the sum of the mass percentage contents of magnesium oxide and zinc oxide is 2.46; The ratio of the sum of the mass percentage contents of zinc oxide and boron oxide in the microcrystalline glass to the sum of the mass percentage contents of zinc oxide and magnesium oxide is 0.68; The sum of the mass percentage contents of zirconia and titanium oxide in the microcrystalline glass is 5.9 wt%.

4. The glass-ceramic according to claim 1 or 2, characterized in that, One or more of the following conditions are met: The transmittance of the microcrystalline glass to visible light is > 88%; The haze of the microcrystalline glass is < 0.4%; The microcrystalline glass has a Vickers hardness > 820 kgf / mm 2 .

5. The glass-ceramic according to claim 1, characterized in that, In the steps of melting, shaping and annealing the mixture, the melting time is 2 to 10 h.

6. The glass-ceramic according to claim 1, characterized in that, In the steps of melting, shaping and annealing the mixture, the annealing time is 3 to 5 h.

7. The glass-ceramic according to claim 1, characterized in that, In the step of heating and heat preservation of the base glass, the heating rate is 5 to 20 ℃ / min.

8. A glass article, characterized by, The microcrystalline glass according to any one of claims 1 to 7.

9. Use of the microcrystalline glass according to any one of claims 1 to 7 in the manufacturing process of electronic devices.

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