Glass-ceramic and preparation method therefor, glass-ceramic product, cover plate assembly, display screen and electronic device

Abstract

Provided in the embodiments of the present application are glass-ceramic and a preparation method therefor, a glass-ceramic product, a cover plate assembly, a display screen and an electronic device. The glass-ceramic comprises a first region and a second region, wherein the first region and the second region each comprise a glass phase and a crystal phase; the first region has a first haze, the second region has a second haze greater than the first haze, and the difference between the first haze and the second haze is greater than or equal to 8%; and the first haze and the second haze are measured when the roughness Ra of both side surfaces of the first region and the second region of the glass-ceramic is ≤ 100 nm. The glass-ceramic has different hazes in different regions, features a large haze difference, a wide adjustable haze range, a good visual three-dimensional effect and a simple preparation process, and facilitates large-scale production and application in fields such as cover plates of electronic devices.

Description

Microcrystalline glass and its preparation methods, microcrystalline glass products, cover plate assemblies, displays and electronic devices

[0001] This application claims priority to Chinese patent application filed on November 8, 2024, with application number 202411603866.1, entitled "Microcrystalline glass and its preparation method, microcrystalline glass articles, cover plate assembly, display screen and electronic device", the entire contents of which are incorporated herein by reference. Technical Field

[0002] This application relates to the field of microcrystalline glass technology, and in particular to a microcrystalline glass and its preparation method, microcrystalline glass articles, cover plate assemblies, displays and electronic devices. Background Technology

[0003] High-strength lithium aluminum silicon glass has been widely used in the field of electronic device cover plates such as mobile phone back covers in recent years due to its advantages such as transparency, high strength, good signal and adjustable CMF (Color, Material & Finishing) process.

[0004] To enhance the consumer experience, the industry designs mobile phone back covers with different levels of haze in different areas. Currently, this is mainly achieved through NCVM (Non-Conductive Vacuum Metallization) coating or etching on the glass surface. However, these methods suffer from limitations such as a small adjustable haze range, weak visual depth, or complex processes. Therefore, it is necessary to provide a glass material with a wide adjustable haze range, good visual effects, and easy availability to better meet application requirements. Summary of the Invention

[0005] In view of this, embodiments of this application provide a microcrystalline glass and its preparation method, a microcrystalline glass product, a cover plate assembly, a display screen, and an electronic device. The microcrystalline glass has different haze in different areas, with large haze differences and a wide range of adjustable haze. It has a good visual three-dimensional effect, a simple preparation process, and is conducive to large-scale production and application in fields such as electronic device cover plates.

[0006] In a first aspect, embodiments of this application provide a microcrystalline glass, the microcrystalline glass comprising a first region and a second region, wherein both the first region and the second region comprise a glass phase and a crystalline phase;

[0007] The crystalline phase in the first region includes one or more of lithium silicate phase, lithium disilicate phase and petalite phase, and the crystalline phase in the second region includes one or more of lithium silicate phase, lithium disilicate phase and petalite phase, as well as one or more of quartz phase, quartz solid solution phase and spodumene phase.

[0008] The first region has a first haze, and the second region has a second haze greater than the first haze. The difference between the first haze and the second haze is greater than or equal to 8%. The first haze and the second haze are measured when the roughness Ra of the two side surfaces of the first region and the second region of the microcrystalline glass is ≤100nm.

[0009] The microcrystalline glass provided in this application embodiment can control the crystal phase in different regions, resulting in different haze regions on the same piece of microcrystalline glass with large haze differences. The haze of each region can be controlled within a wide range, providing a good visual three-dimensional effect. The preparation process is simple, eliminating the need for additional coating or etching processes after melting and molding to obtain the microcrystalline glass body, thus achieving haze differences. Furthermore, it can be chemically strengthened, which is beneficial for large-scale production and application in fields such as electronic device covers, improving the appearance and strength of the cover and enhancing the user experience.

[0010] In this embodiment of the application, the sum of the mass percentages of the quartz phase, quartz solid solution phase, and spodumene phase in the second region is greater than or equal to 5%. The higher the content of the quartz phase, quartz solid solution phase, and spodumene phase, the more beneficial it is to improving the haze of the second region.

[0011] In some embodiments of this application, the crystalline phase in the first region does not include the quartz phase, quartz solid solution phase, or spodumene phase.

[0012] In this embodiment of the application, the crystalline phase in the first region includes a lithium disilicate phase and a lithium feldspar phase; or...

[0013] The crystalline phases in the first region include lithium silicate phase, lithium disilicate phase, and petalite phase; or,

[0014] The crystalline phase in the first region includes a lithium silicate phase; or,

[0015] The crystalline phases in the first region include lithium silicate phase and petalite phase.

[0016] In this embodiment of the application, the crystalline phase in the second region includes lithium disilicate phase, lithium feldspar phase, and quartz phase; or...

[0017] The crystalline phases in the second region include lithium disilicate phase, petalite phase, quartz phase, and spodumene phase; or,

[0018] The crystalline phases in the second region include lithium silicate phase, quartz solid solution phase, and spodumene phase; or,

[0019] The crystalline phases in the second region include lithium disilicate, petalite, and spodumene; or,

[0020] The crystalline phases in the second region include lithium disilicate phase, petalite phase, and quartz solid solution phase; or,

[0021] The crystalline phases in the second region include lithium disilicate phase, lithite phase, quartz solid solution phase, and spodumene phase.

[0022] The first region does not contain quartz phase, quartz solid solution phase, or spodumene phase, which is beneficial for achieving lower haze in the first region. By controlling the different crystalline phases contained in the first and second regions, microcrystalline glass with different haze differences can be obtained to meet different application requirements.

[0023] In other embodiments of this application, the crystalline phase in the first region further includes one or more of the following: quartz phase, quartz solid solution phase, and spodumene phase.

[0024] In this embodiment of the application, the crystalline phase in the first region includes lithium disilicate phase, lithium feldspar phase, and quartz phase; or...

[0025] The crystalline phases in the first region include lithium silicate phase and quartz solid solution phase; or,

[0026] The crystalline phases in the first region include lithium disilicate phase and quartz solid solution phase.

[0027] In this embodiment of the application, the crystalline phase in the second region includes lithium disilicate phase, lithium feldspar phase, and quartz phase; or...

[0028] The crystalline phases in the second region include lithium disilicate phase, petalite phase, quartz phase, and spodumene phase; or,

[0029] The crystalline phases in the second region include a quartz solid solution phase and a spodumene phase.

[0030] The presence of quartz phase, quartz solid solution phase, or spodumene phase in the first region is beneficial for achieving higher haze. By controlling the different crystalline phases contained in the first and second regions, microcrystalline glass with varying haze can be obtained to meet different application requirements.

[0031] In this embodiment, the sum of the mass percentages of the quartz phase, quartz solid solution phase, and spodumene phase in the second region is greater than the sum of the mass percentages of the quartz phase, quartz solid solution phase, and spodumene phase in the first region. Higher contents of the quartz phase, quartz solid solution phase, and spodumene phase are more conducive to improving haze; therefore, this design is beneficial for widening the haze difference between the first and second regions.

[0032] In this embodiment, the total mass percentage of the crystalline phase in the second region is greater than that in the first region. A larger total mass percentage of the crystalline phase in the second region is more conducive to controlling the haze difference between the first and second regions.

[0033] In this embodiment, the total mass percentage of the crystalline phase in the first region is greater than or equal to 15%. For fine grains, a high total content of the crystalline phase in the first region is beneficial to improving the mechanical properties of the glass-ceramic, such as strength and toughness.

[0034] In this embodiment, the average crystal size in the second region is larger than the average crystal size in the first region. A larger average crystal size in the second region compared to the first region is more advantageous for controlling the haze difference between the first and second regions.

[0035] In this embodiment, the average crystal size in the first region is 10 nm to 150 nm; the average crystal size in the second region is 50 nm to 2000 nm. The smaller grain size of the crystal phase in the first region is beneficial for reducing haze in the first region and improving the mechanical properties of the glass-ceramic, such as strength. The relatively larger grain size of the crystal phase in the second region is beneficial for widening the haze difference between the first and second regions. Simultaneously, within this suitable range, it is beneficial for ensuring that the mechanical properties of the glass-ceramic, such as strength, are at a high level.

[0036] In this embodiment, the first haze is in the range of 0-20%; the second haze is in the range of 8%-95%. Controlling the first haze to a relatively small value and the second haze to a relatively large value is beneficial for obtaining an appearance effect with a large difference in haze.

[0037] In this embodiment of the application, when the microcrystalline glass has a thickness of 0.3mm to 0.7mm, the transmittance is tested in the first region. The L value is 40 to 99, the A value is -100 to 100, and the B value is -100 to 100. The L value of the second region is 20 to 95, the A value is -100 to 100, and the B value is -100 to 100.

[0038] In this embodiment, the microcrystalline glass further includes a third region located between the first region and the second region, wherein the haze of the third region gradually increases from the first region to the second region. The introduction of the third region allows the microcrystalline glass to achieve richer haze variations, which can enhance the user experience when used in fields such as electronic device covers.

[0039] In this embodiment of the application, the third region includes a glassy phase and a crystalline phase. The crystalline phase in the third region includes one or more of lithium silicate phase, lithium disilicate phase and lithite phase, as well as one or more of quartz phase, quartz solid solution phase and spodumene phase.

[0040] In some embodiments of this application, the sum of the mass percentages of the quartz phase, the quartz solid solution phase, and the spodumene phase gradually increases from the first region to the second region in the third region.

[0041] In this embodiment of the application, the crystal phase in the third region includes lithium disilicate phase, sulphite phase and quartz phase; or includes lithium silicate phase, lithium disilicate phase, sulphite phase and quartz phase; or includes lithium disilicate phase, sulphite phase, quartz phase and spodumene phase.

[0042] In this embodiment of the application, the LAB value of the third region is between the LAB value of the first region and the LAB value of the second region, and gradually changes from the first region to the second region.

[0043] In this embodiment of the application, the microcrystalline glass comprises the following components by mass percentage:

[0044] Li2O: 5%–20%,

[0045] SiO2: 50%–85%,

[0046] Al2O3: 4%–15%,

[0047] P2O5: 0.5%–5%,

[0048] ZrO2: 2%–10%,

[0049] TiO2: 0-5%,

[0050] Na2O: 0-5%,

[0051] K2O: 0-5%,

[0052] B2O3: 0-5%,

[0053] Coloring component: 0-5%.

[0054] In this embodiment of the application, the microcrystalline glass satisfies: 4≤(Li2O+SiO2) / Al2O3≤25.

[0055] In this embodiment of the application, the microcrystalline glass satisfies: 6≤(Li2O+SiO2) / Al2O3≤15.

[0056] In this embodiment of the application, the microcrystalline glass satisfies: 0.5≤Li2O / Al2O3≤5.

[0057] In this embodiment, the microcrystalline glass satisfies the following condition: 0.9 ≤ Li₂O / Al₂O₃ ≤ 2.5. Controlling the relative content of Li₂O and Al₂O₃ in the microcrystalline glass is beneficial for regulating the ratio of lithium silicate, lithium disilicate, litharge, quartz phase, and quartz solid solution phase, as well as the chemically enhanced ion exchange capacity of the microcrystalline glass.

[0058] In this embodiment of the application, the microcrystalline glass satisfies: 4≤(SiO2+Al2O3) / (P2O5+TiO2+ZrO2)≤30.

[0059] In this embodiment, the microcrystalline glass satisfies: 8 ≤ (SiO2 + Al2O3) / (P2O5 + TiO2 + ZrO2) ≤ 16. Controlling the ratio of (SiO2 + Al2O3) / (P2O5 + TiO2 + ZrO2) within a suitable range is beneficial for the smooth progress of the melting process, for controlling the formation of coarse crystals, for improving the overall optical performance uniformity of the microcrystalline glass, and for enhancing the continuity of the haze gradient effect.

[0060] The microcrystalline glass of this application embodiment, through the synergistic effect of the above-mentioned components, can achieve a large haze difference in appearance on the same piece of microcrystalline glass without introducing additional operations, and can be chemically strengthened to obtain a large compressive stress layer depth, a better stress value, and a higher compressive strength.

[0061] In this embodiment of the application, the coloring component includes one or more elemental or oxide coloring elements, and the coloring elements include one or more of Au, Ag, Cu, Ni, Co, Fe, Mn, Cr, V, Ti, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu.

[0062] In this embodiment, the microcrystalline glass is either non-chemically strengthened or chemically strengthened; the thickness of the microcrystalline glass is 0.3 mm to 0.7 mm.

[0063] In this embodiment, the chemically strengthened glass-ceramic has a tensile stress layer, the average tensile stress of the chemically strengthened glass-ceramic is greater than 30 MPa, and the compressive strength of the chemically strengthened glass-ceramic is greater than 10 kgf.

[0064] In this embodiment of the application, the chemically strengthened microcrystalline glass has a compressive stress layer with a depth greater than 70 μm; the compressive stress CS50 at a depth of 50 μm in the compressive stress layer is ≥40 MPa.

[0065] A second aspect of this application provides a microcrystalline glass, the microcrystalline glass comprising Li2O, SiO2 and Al2O3, wherein the mass percentage of the three components in the microcrystalline glass satisfies 4≤(Li2O+SiO2) / Al2O3≤25. The microcrystalline glass includes a first region and a second region, both the first region and the second region comprising a glass phase and a crystalline phase. The first region has a first haze, and the second region has a second haze greater than the first haze. The difference between the first haze and the second haze is greater than or equal to 8%. The first haze and the second haze are measured when the roughness Ra of the two side surfaces of the first region and the second region of the microcrystalline glass is ≤100nm.

[0066] The microcrystalline glass provided in this application, by controlling the mass percentages of Li2O, SiO2, and Al2O3 in the microcrystalline glass to meet the specific ratio mentioned above, is beneficial to enable the microcrystalline glass to precipitate crystalline phases with large optical haze variations, thereby achieving haze control in the first and second regions. This microcrystalline glass may precipitate lithium silicate, lithium disilicate, or petalite phases with refractive indices similar to the glass phase and relatively fine crystals, resulting in lower haze; it may also precipitate quartz or quartz solid solution phases with moderate refractive indices similar to the glass phase and relatively larger crystals. These crystalline phases, combined with lithium silicate, lithium disilicate, and petalite, can widen the haze range of the microcrystalline glass; it may also precipitate spodumene phases with large refractive indices similar to the glass phase. The coarse crystals of the spodumene phase can further expand the haze range of the microcrystalline glass.

[0067] In this embodiment of the application, the microcrystalline glass satisfies: 6≤(Li2O+SiO2) / Al2O3≤15.

[0068] In this embodiment of the application, the mass percentages of Li2O and Al2O3 in the microcrystalline glass satisfy 0.5≤Li2O / Al2O3≤5.

[0069] In this embodiment, the microcrystalline glass satisfies the following condition: 0.9 ≤ Li₂O / Al₂O₃ ≤ 2.5. Controlling the relative content of Li₂O and Al₂O₃ within this suitable range allows for appropriate content of lithium silicate, lithium disilicate, lithopone, quartz phase, and quartz solid solution phase in the microcrystalline glass. This results in good optical properties and ion exchange capacity, and also provides greater space for subsequent heating, which is beneficial for forming different regions with distinct optical characteristics (including haze, LAB, etc.) (such as the first and second regions), and also for forming intermediate transition regions with continuous haze changes and good gradient effects (such as the third region).

[0070] In this embodiment of the application, the microcrystalline glass comprises the following components by mass percentage:

[0071] Li2O: 5%–20%,

[0072] SiO2: 50%–85%,

[0073] Al2O3: 4%–15%,

[0074] P2O5: 0.5%–5%,

[0075] ZrO2: 2%–10%,

[0076] TiO2: 0-5%,

[0077] Na2O: 0-5%,

[0078] K2O: 0-5%,

[0079] B2O3: 0-5%,

[0080] Coloring component: 0-5%.

[0081] In this embodiment of the application, the microcrystalline glass satisfies: 4≤(SiO2+Al2O3) / (P2O5+TiO2+ZrO2)≤30.

[0082] In this embodiment, the microcrystalline glass satisfies: 8 ≤ (SiO2 + Al2O3) / (P2O5 + TiO2 + ZrO2) ≤ 16. Controlling the ratio of (SiO2 + Al2O3) / (P2O5 + TiO2 + ZrO2) within a suitable range is beneficial for the smooth progress of the melting process, for controlling the formation of coarse crystals, for improving the overall optical performance uniformity of the microcrystalline glass, and for enhancing the continuity of the haze gradient effect.

[0083] The microcrystalline glass of this application embodiment, through the synergistic effect of the above-mentioned components, can achieve a large haze difference in appearance on the same piece of microcrystalline glass without introducing additional operations, and can be chemically strengthened to obtain a large compressive stress layer depth, a better stress value, and a higher compressive strength.

[0084] In this embodiment of the application, the crystalline phase in the first region includes one or more of the following: lithium silicate phase, lithium disilicate phase, lepidolite phase, quartz phase, quartz solid solution phase, and spodumene phase.

[0085] The crystalline phase in the second region includes at least two of the following: lithium silicate phase, lithium disilicate phase, lepidolite phase, quartz phase, quartz solid solution phase, and spodumene phase.

[0086] In this embodiment of the application, the crystalline phase in the first region includes one or more of lithium silicate phase, lithium disilicate phase, and spodumene phase, and may or may not include one or more of quartz phase, quartz solid solution phase, and spodumene phase; the crystalline phase in the second region includes one or more of lithium silicate phase, lithium disilicate phase, and spodumene phase, as well as one or more of quartz phase, quartz solid solution phase, and spodumene phase.

[0087] In this embodiment of the application, the second region contains more types of crystal phases than the first region; and / or, the total mass percentage of crystal phases in the second region is greater than the total mass percentage of crystal phases in the first region; and / or, the average crystal size in the second region is greater than the average crystal size in the first region.

[0088] In this embodiment, the sum of the mass percentages of the quartz phase, quartz solid solution phase, and spodumene phase in the second region is greater than the sum of the mass percentages of the quartz phase, quartz solid solution phase, and spodumene phase in the first region. Higher contents of the quartz phase, quartz solid solution phase, and spodumene phase are more conducive to improving haze; therefore, this design is beneficial for widening the haze difference between the first and second regions.

[0089] In this embodiment of the application, the sum of the mass percentages of the quartz phase, quartz solid solution phase, and spodumene phase in the second region is greater than or equal to 5%. The higher the content of the quartz phase, quartz solid solution phase, and spodumene phase, the more beneficial it is to improving the haze of the second region.

[0090] In this embodiment of the application, the crystal phases in both the first region and the second region include lithium disilicate phase, lithium feldspar phase, and quartz phase; or,

[0091] The crystalline phases in the first region include lithium disilicate phase and petalite phase, and the crystalline phases in the second region include lithium disilicate phase, petalite phase, and quartz phase; or,

[0092] The crystalline phases in the first region include lithium silicate phase and petalite phase, and the crystalline phases in the second region include lithium disilicate phase, petalite phase, and quartz phase; or,

[0093] The crystalline phases in the first region include lithium silicate phase, lithium disilicate phase, and petalite phase; the crystalline phases in the second region include lithium disilicate phase, petalite phase, and quartz phase; or,

[0094] The crystalline phases in the first region include lithium disilicate phase, petalite phase, and quartz phase; the crystalline phases in the second region include lithium disilicate phase, petalite phase, quartz phase, and spodumene phase; or,

[0095] The crystalline phases in the first region include lithium disilicate phase and petalite phase, and the crystalline phases in the second region include lithium disilicate phase, petalite phase, quartz phase, and spodumene phase; or,

[0096] The crystalline phase in the first region includes a lithium silicate phase, and the crystalline phase in the second region includes a lithium silicate phase, a quartz solid solution phase, and a spodumene phase; or,

[0097] The crystalline phases in the first region include lithium silicate phase and quartz solid solution phase, and the crystalline phases in the second region include quartz solid solution phase and spodumene phase; or,

[0098] The crystalline phases in the first region include lithium silicate phase, lithium disilicate phase, and petalite phase; the crystalline phases in the second region include lithium disilicate phase, petalite phase, and spodumene phase; or,

[0099] The crystalline phases in the first region include lithium disilicate phase and petalite phase, and the crystalline phases in the second region include lithium disilicate phase, petalite phase, and quartz solid solution phase; or,

[0100] The crystalline phases in the first region include lithium disilicate phase and petalite phase, and the crystalline phases in the second region include lithium disilicate phase, petalite phase, quartz solid solution phase, and spodumene phase; or,

[0101] The crystalline phases in the first region include lithium disilicate phase and quartz solid solution phase, and the crystalline phases in the second region include quartz solid solution phase and spodumene phase; or,

[0102] The crystalline phases in the first region include lithium silicate and petalite phases, while the crystalline phases in the second region include lithium disilicate, petalite, and quartz solid solution phases. By controlling the different crystalline phases contained in the first and second regions, microcrystalline glass with varying haze can be obtained to meet different application requirements.

[0103] In this embodiment, the total mass percentage of the crystalline phase in the second region is greater than that in the first region. A larger total mass percentage of the crystalline phase in the second region is more conducive to controlling the haze difference between the first and second regions.

[0104] In this embodiment, the total mass percentage of the crystalline phase in the first region is greater than or equal to 15%. For fine grains, a high total content of the crystalline phase in the first region is beneficial to improving the mechanical properties of the glass-ceramic, such as strength and toughness.

[0105] In this embodiment, the average crystal size in the second region is larger than the average crystal size in the first region. A larger average crystal size in the second region compared to the first region is more advantageous for controlling the haze difference between the first and second regions.

[0106] In this embodiment, the average crystal size in the first region is 10 nm to 150 nm; the average crystal size in the second region is 50 nm to 2000 nm. The smaller grain size of the crystal phase in the first region is beneficial for reducing haze in the first region and improving the mechanical properties of the glass-ceramic, such as strength. The relatively larger grain size of the crystal phase in the second region is beneficial for widening the haze difference between the first and second regions. Simultaneously, within this suitable range, it is beneficial for ensuring that the mechanical properties of the glass-ceramic, such as strength, are at a high level.

[0107] In this embodiment, the first haze is in the range of 0-20%; the second haze is in the range of 8%-95%. Controlling the first haze to a relatively small value and the second haze to a relatively large value is beneficial for obtaining an appearance effect with a large difference in haze.

[0108] In this embodiment of the application, when the microcrystalline glass has a thickness of 0.3mm to 0.7mm, the transmittance is tested in the first region. The L value is 40 to 99, the A value is -100 to 100, and the B value is -100 to 100. The L value of the second region is 20 to 95, the A value is -100 to 100, and the B value is -100 to 100.

[0109] In this embodiment, the microcrystalline glass further includes a third region located between the first region and the second region, wherein the haze of the third region gradually increases from the first region to the second region. The introduction of the third region allows the microcrystalline glass to achieve richer haze variations, which can enhance the user experience when used in fields such as electronic device covers.

[0110] In this embodiment of the application, the third region includes a glassy phase and a crystalline phase. The crystalline phase in the third region includes one or more of lithium silicate phase, lithium disilicate phase, and spodumene phase, as well as one or more of quartz phase, quartz solid solution phase, and spodumene phase. In the third region, from the first region to the second region, the sum of the mass percentages of quartz phase, quartz solid solution phase, and spodumene phase gradually increases.

[0111] In this embodiment of the application, the crystal phase in the third region includes lithium disilicate phase, sulphite phase and quartz phase; or includes lithium silicate phase, lithium disilicate phase, sulphite phase and quartz phase; or includes lithium disilicate phase, sulphite phase, quartz phase and spodumene phase.

[0112] In this embodiment of the application, the LAB value of the third region is between the LAB value of the first region and the LAB value of the second region, and gradually changes from the first region to the second region.

[0113] In this embodiment of the application, the coloring component includes one or more elemental or oxide coloring elements, and the coloring elements include one or more of Au, Ag, Cu, Ni, Co, Fe, Mn, Cr, V, Ti, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu.

[0114] In this embodiment, the microcrystalline glass is either non-chemically strengthened or chemically strengthened; the thickness of the microcrystalline glass is 0.3 mm to 0.7 mm.

[0115] In this embodiment, the chemically strengthened glass-ceramic has a tensile stress layer, and the average tensile stress of the chemically strengthened glass-ceramic is greater than 30 MPa; the compressive strength of the chemically strengthened glass-ceramic is greater than 10 kgf. A suitable average tensile stress helps the glass-ceramic to have high strength while preventing excessively small fragments after failure and breakage.

[0116] In this embodiment, the chemically strengthened microcrystalline glass has a compressive stress layer with a depth greater than 70 μm; the compressive stress CS50 at a depth of 50 μm in the compressive stress layer is ≥40 MPa. This results in high strength and superior drop resistance.

[0117] A third aspect of this application provides a method for preparing microcrystalline glass, comprising:

[0118] After the raw materials of each component of the microcrystalline glass are melted and molded, the glass to be crystallized is obtained; the glass to be crystallized includes a first crystallization region and a second crystallization region;

[0119] The glass to be crystallized is heated and crystallized to obtain microcrystalline glass; wherein, the heating and crystallization includes at least one non-uniform heating and crystallization, wherein the non-uniform heating and crystallization is to provide different thermal fields to the first region to be crystallized and the second region to be crystallized for heating respectively;

[0120] The microcrystalline glass includes a first region and a second region. The first region to be crystallized is used to form the first region, and the second region to be crystallized is used to form the second region. Both the first region and the second region include a glass phase and a crystalline phase dispersed in the glass phase. The first region has a first haze, and the second region has a second haze greater than the first haze. The difference between the first haze and the second haze is greater than or equal to 8%. The first haze and the second haze are measured when the roughness Ra on both sides of the first region and the second region of the microcrystalline glass is ≤100nm.

[0121] The method for preparing microcrystalline glass in this application embodiment can be achieved by controlling the heating conditions of different regions to be crystallized during the crystallization process, and the operation is simple.

[0122] In this embodiment of the application, the preparation method further includes a hot bending process after the heating and crystallization. The desired 3D morphology of the microcrystalline glass can be obtained after hot bending.

[0123] In this embodiment of the application, during the non-uniform heating crystallization process, a heat insulation component is used to shield the first region to be crystallized, while the second region to be crystallized is not shielded, so as to provide different thermal fields for the first region to be crystallized and the second region to be crystallized.

[0124] The fourth aspect of this application provides a method for preparing microcrystalline glass, comprising:

[0125] After the raw materials of each component of the microcrystalline glass are melted and molded, the glass to be crystallized is obtained; the glass to be crystallized includes a first crystallization region and a second crystallization region;

[0126] The glass to be crystallized is heated and then hot-bent to obtain microcrystalline glass;

[0127] Wherein, the heating crystallization is uniform heating crystallization, which means heating the first region to be crystallized and the second region to be crystallized by providing the same thermal field;

[0128] The hot bending includes at least one non-uniform hot field hot bending, wherein the non-uniform hot field hot bending provides different hot fields to the first region to be crystallized and the second region to be crystallized during the hot bending;

[0129] The microcrystalline glass includes a first region and a second region. The first region to be crystallized is used to form the first region, and the second region to be crystallized is used to form the second region. Both the first region and the second region include a glass phase and a crystalline phase dispersed in the glass phase. The first region has a first haze, and the second region has a second haze greater than the first haze. The difference between the first haze and the second haze is greater than or equal to 8%. The first haze and the second haze are measured when the roughness Ra on both sides of the first region and the second region of the microcrystalline glass is ≤100nm.

[0130] The method for preparing microcrystalline glass in this application embodiment can be achieved by controlling the heating of different regions to be crystallized during the hot bending process, which is simple to operate.

[0131] In this embodiment of the application, during the non-uniform heating crystallization process, a heat insulation component is used to shield the first region to be crystallized, while the second region to be crystallized is not shielded, so as to provide different thermal fields for the first region to be crystallized and the second region to be crystallized.

[0132] In this embodiment of the application, the provision of different thermal fields to the first region to be crystallized and the second region to be crystallized during the non-uniform thermal bending process specifically involves:

[0133] A hot bending die with non-uniform thermal conductivity is used, wherein the thermal conductivity of the portion of the hot bending die corresponding to the first region to be crystallized is less than the thermal conductivity of the portion corresponding to the second region to be crystallized; and / or,

[0134] A hot bending machine with non-uniform heating element power distribution is used, wherein the heating element power at the location corresponding to the first crystallization region is less than the heating element power at the location corresponding to the second crystallization region; and / or,

[0135] A hot bending machine with non-uniform power distribution of heating tubes is used, wherein the cooling water flow rate of the part of the hot bending machine corresponding to the first crystallization area is greater than the cooling water flow rate of the part corresponding to the second crystallization area.

[0136] In this embodiment of the application, the hot bending further includes at least one uniform hot bending, wherein the uniform hot bending provides the same hot field to the first region to be crystallized and the second region to be crystallized during the hot bending.

[0137] A fifth aspect of this application provides a microcrystalline glass article, comprising a body layer comprising the microcrystalline glass described in the first or second aspect, or the microcrystalline glass prepared by the method described in the third aspect, or the microcrystalline glass prepared by the method described in the fourth aspect. This microcrystalline glass article can be of any shape and size, and can be a component applied in various fields and scenarios, such as a cover plate or decorative part for electronic devices.

[0138] In this embodiment of the application, the microcrystalline glass product further includes an additional layer disposed on the surface of the body layer. The additional layer may be provided according to actual functional needs, for example, the additional layer may include an anti-fingerprint layer, etc.

[0139] A sixth aspect of this application provides a cover plate assembly, including a cover plate and a decorative element mounted on the cover plate. The cover plate includes the microcrystalline glass article described in the fifth aspect. The cover plate assembly, including the microcrystalline glass article of this application, can achieve a haze variation effect, enhancing the user experience.

[0140] A seventh aspect of this application provides a display screen, including a display module and a display screen cover disposed on one side of the display module, wherein the display screen cover comprises the microcrystalline glass article described in the fifth aspect.

[0141] An eighth aspect of this application provides an electronic device including a housing assembly comprising the microcrystalline glass article described in the fifth aspect. The housing assembly of the electronic device, comprising the microcrystalline glass article of this application, can achieve a haze-varying appearance effect, thereby enhancing the user experience.

[0142] In some embodiments of this application, the housing assembly includes a display cover and a back cover assembled on opposite sides of the electronic device; wherein the display cover and / or the back cover includes the microcrystalline glass article.

[0143] In other embodiments of this application, the housing assembly includes a display cover and a rear cover assembled on opposite sides of the electronic device, and a camera trim mounted on the rear cover, wherein the display cover, and / or the rear cover, and / or the camera trim comprises the microcrystalline glass article. Attached Figure Description

[0144] Figure 1 is a cross-sectional schematic diagram of a microcrystalline glass 100 provided in an embodiment of this application;

[0145] Figure 2 is a schematic diagram of the distribution of different regions of the microcrystalline glass 100 provided in an embodiment of this application;

[0146] Figure 3 is a cross-sectional schematic diagram of the microcrystalline glass 100 provided in another embodiment of this application;

[0147] Figure 4 is a schematic diagram of the distribution of different regions of the microcrystalline glass 100 provided in another embodiment of this application;

[0148] Figure 5 is a schematic diagram of the installation of the heat insulation component in one embodiment of this application;

[0149] Figure 6 is a schematic diagram of the installation of the heat insulation component in another embodiment of this application;

[0150] Figure 7 is a schematic diagram showing that the same thermal field is provided to the first and second regions to be crystallized during the uniform heating crystallization process;

[0151] Figure 8 is a schematic diagram showing that the same thermal field is provided to the first and second regions to be crystallized during the uniform thermal bending process of the embodiment of this application.

[0152] Figures 9 to 14 are schematic diagrams showing different methods of providing different thermal fields during the non-uniform thermal bending process according to embodiments of this application;

[0153] Figure 15 is a schematic cross-sectional view of the microcrystalline glass article 200 provided in the embodiment of this application;

[0154] Figure 16 is a structural schematic diagram of the cover plate assembly 300 provided in an embodiment of this application;

[0155] Figure 17 is a schematic diagram of the structure of the electronic device 400 provided in the embodiment of this application. Detailed Implementation

[0156] The embodiments of this application will now be described in conjunction with the accompanying drawings.

[0157] To enhance the aesthetics, the industry designs mobile phone back covers with varying degrees of haze in different areas. Currently, this is primarily achieved through NCVM coating or etching on the glass surface. NCVM coating uses optical interference to create different color spectral curves through coating layer stacking, and color changes are achieved by controlling the coating thickness. This allows for different haze levels and LAB values ​​on the same piece of glass, but the adjustable range of haze is very small, resulting in a mirror-like effect without depth. Etching involves exposure and development, surface matte treatment, stripping, and chemical polishing to create a surface layer with varying haze. This approach only improves surface reflection, lacking depth and texture, and is complex. Therefore, this application provides a microcrystalline glass with different haze levels in different areas, a wide adjustable range of haze, good visual depth, and a simple manufacturing process, facilitating large-scale production for applications such as electronic device cover plates.

[0158] Referring to Figures 1 and 2, Figure 1 is a cross-sectional schematic diagram of a microcrystalline glass 100 provided in an embodiment of this application; Figure 2 is a schematic diagram of the distribution of different regions of the microcrystalline glass 100 provided in an embodiment of this application. The microcrystalline glass 100 includes a first region 101 and a second region 102, and both the first region 101 and the second region 102 include a glass phase (11, 12) and a crystalline phase (21, 22).

[0159] The first region 101 has a first haze H1, and the second region 102 has a second haze H2 that is greater than the first haze H1. The difference between the first haze H1 and the second haze H2 (i.e., H2-H1) is greater than or equal to 8%. The first haze H1 and the second haze H2 are measured when the roughness Ra of the two side surfaces of the first region 101 and the second region 102 of the microcrystalline glass 100 is ≤100nm.

[0160] The microcrystalline glass provided in this application has different haze areas on the same piece of microcrystalline glass, and the haze difference is large. No additional processes such as coating or etching are required to achieve the haze difference, which is conducive to large-scale production and application in fields such as electronic device covers, improving the appearance and strength of the cover and enhancing the user experience.

[0161] In this embodiment of the application, the first region 101 and the second region 102 are arranged side by side in a direction perpendicular to the thickness direction of the glass-ceramic 100. The first region 101 includes a first surface S1 and a second surface S2 arranged opposite to each other along the thickness direction of the glass-ceramic 100. The second region 102 includes a third surface S3 and a fourth surface S4 arranged opposite to each other along the thickness direction of the glass-ceramic 100. The first surface S1 and the third surface S3 are arranged on the same side, and the second surface S2 and the fourth surface S4 are arranged on the same side.

[0162] In this embodiment, the two side surfaces of the first region 101, namely the first surface S1 and the second surface S2, can both be smooth surfaces with a roughness Ra ≤ 100 nm; or one of them can be a smooth surface with a roughness Ra ≤ 100 nm, and the other can be a rough surface with a roughness Ra > 100 nm; or both can be rough surfaces with a roughness Ra > 100 nm. Similarly, the two side surfaces of the second region 102, namely the third surface S3 and the fourth surface S4, can both be smooth surfaces with a roughness Ra ≤ 100 nm; or one of them can be a smooth surface with a roughness Ra ≤ 100 nm, and the other can be a rough surface with a roughness Ra > 100 nm; or both can be rough surfaces with a roughness Ra > 100 nm. This rough surface can be obtained, for example, by etching. When the surface roughness Ra is greater than 100 nm, the reflection effect of the surface roughness can be used to further enhance the haze of the glass-ceramic in the corresponding area. That is, the haze of the glass-ceramic 100 in the corresponding area is caused by both the internal structure of the glass-ceramic and the surface roughness. Specifically, the surface roughness Ra can be greater than 100 nm and less than or equal to 10 μm, for example, but not limited to, 150 nm, 200 nm, 500 nm, 800 nm, 1 μm, 3 μm, 5 μm, 7 μm, and 10 μm.

[0163] Haze is the percentage of transmitted light intensity that deviates from the incident light by more than 2.5° from the total transmitted light intensity. In this application, the first haze H1 and the second haze H2 are measured when the roughness Ra of the two side surfaces of the first region 101 and the second region 102 of the microcrystalline glass 100 is ≤100nm. Therefore, when the first surface S1, the second surface S2, the third surface S3, and the fourth surface S4 of the microcrystalline glass 100 are all smooth surfaces with a roughness Ra ≤100nm, the first haze H1 and the second haze H2 can be directly measured using optical instruments. When the first surface S1, the second surface S2, the third surface S3, or the fourth surface S4 of the microcrystalline glass 100 are uneven surfaces with a roughness Ra >100nm, the first surface S1, the second surface S2, the third surface S3, and the fourth surface S4 need to be ground smooth to a roughness Ra ≤100nm before the first haze H1 and the second haze H2 can be measured using optical instruments. Optical instruments could be, for example, Konica Minolta's CM-3600A or CM36-DG spectrophotometers.

[0164] In this embodiment, the sides of the first region 101 and the second region 102 along the thickness direction of the microcrystalline glass are perpendicular surfaces. The dimensions (i.e., the area, or projected area along the thickness direction) of the first region 101 and the second region 102 are not limited; they can be any size equivalent to a circle with a diameter less than 30 mm, such as 4 mm, 8 mm, 25.4 mm, etc.; or any size equivalent to a circle with a diameter greater than or equal to 30 mm, depending on actual needs. The shapes of the first region 101 and the second region 102 are not limited; they can be various regular or irregular shapes. The dimensions of the first region 101 and the second region 102 can be the same or different, and their shapes can be the same or different.

[0165] It should be noted that when obtaining the haze of the first region 101 and the second region 102, which are larger than the single measurement area of ​​the optical instrument (e.g., with a diameter of 4 mm, 8 mm, or 25.4 mm), multiple measurements can be taken and the average value taken. When the size of the first region 101 and the second region 102 is larger than the size of the single measurement area of ​​the optical instrument, the haze at each position in the first region 101 is the same or substantially the same within the allowable error range of the process, with a maximum haze difference of less than 5%, and the positions of the highest and lowest haze values ​​are randomly distributed in the first region 101; the haze at each position in the second region 102 is the same or substantially the same within the allowable error range of the process, with a maximum haze difference of less than 5%, and the positions of the highest and lowest haze values ​​are randomly distributed in the second region 102.

[0166] In this embodiment, the crystalline phase 12 in the first region 101 includes one or more of lithium silicate, lithium disilicate, lepidolite, quartz, quartz solid solution, and spodumene; the crystalline phase 22 in the second region 102 includes at least two of lithium silicate, lithium disilicate, lepidolite, quartz, quartz solid solution, and spodumene. Introducing the aforementioned crystalline phases into the first region 101 and the second region 102, and controlling the distribution of these crystalline phases in the first region 101 and the second region 102, allows for haze control in both regions. The presence of lithium silicate, lithium disilicate, and lepidolite is beneficial for achieving low haze, while the presence of quartz, quartz solid solution, and spodumene is beneficial for increasing haze.

[0167] In some embodiments of this application, the crystalline phase 12 in the first region 101 includes one or more of lithium silicate, lithium disilicate, and petalite, and may or may not include one or more of quartz, quartz solid solution, and spodumene; the crystalline phase 22 in the second region 102 includes one or more of lithium silicate, lithium disilicate, and petalite, as well as one or more of quartz, quartz solid solution, and spodumene. In this embodiment, the microcrystalline glass 100 simultaneously includes a first type of crystalline phase and a second type of crystalline phase, wherein the first type of crystalline phase includes one or more of lithium silicate, lithium disilicate, and petalite, and the second type of crystalline phase includes one or more of quartz, quartz solid solution, and spodumene. The refractive index of the first type of crystalline phase is not significantly different from that of the glassy phase, which is beneficial for achieving low haze. The refractive index of the second type of crystalline phase is relatively significantly different from that of the glassy phase, which is beneficial for increasing haze. Moreover, among these, compared to one or more combinations of quartz phase and / or quartz solid solution phase with lithium silicate phase, lithium disilicate phase, and petalite phase, one or more combinations of spodumene phase with lithium silicate phase, lithium disilicate phase, and petalite phase can further increase the haze of the glass-ceramic. By introducing the above-mentioned crystalline phases into the glass-ceramic 100 and controlling the distribution of the crystalline phases, a large degree of haze difference control can be achieved. Thus, different haze difference distributions can be achieved on the same piece of glass-ceramic without additional operations other than melting and molding. The process is simple and does not affect the further chemical strengthening.

[0168] The microcrystalline glass provided in this application embodiment can control the crystal phase in different regions, resulting in different haze regions on the same piece of microcrystalline glass with large haze differences. The haze of each region can be controlled within a wide range, providing a good visual three-dimensional effect. The preparation process is simple, eliminating the need for additional coating or etching processes after melting and molding to obtain the microcrystalline glass body, thus achieving haze differences. Furthermore, it can be chemically strengthened, which is beneficial for large-scale production and application in fields such as electronic device covers, improving the appearance and strength of the cover and enhancing the user experience.

[0169] In some embodiments of this application, the first region 101 includes one or more of lithium silicate phase, lithium disilicate phase, and petalite phase, but excludes one or more of quartz phase, quartz solid solution phase, and spodumene phase. That is, the first region 101 includes only one or more of lithium silicate phase, lithium disilicate phase, and petalite phase. The first region 101 including only the first type of crystalline phase is advantageous for obtaining lower haze. Exemplarily, the crystalline phase in the first region 101 includes lithium disilicate phase and petalite phase; or, the crystalline phase in the first region 101 includes lithium silicate phase, lithium disilicate phase, and petalite phase; or, the crystalline phase in the first region 101 includes lithium silicate phase; or, the crystalline phase in the first region 101 includes lithium silicate phase and petalite phase.

[0170] In other embodiments of this application, the first region 101 includes one or more of lithium silicate phase, lithium disilicate phase, and lepidolite phase, and also includes one or more of quartz phase, quartz solid solution phase, and spodumene phase. The combination of the second type of crystalline phase and the first type of crystalline phase in the first region 101 is beneficial for obtaining a relatively higher haze. Exemplarily, the crystalline phase in the first region 101 includes lithium disilicate phase, lepidolite phase, and quartz phase; or, the crystalline phase in the first region 101 includes lithium silicate phase and quartz solid solution phase; or, the crystalline phase in the first region 101 includes lithium disilicate phase and quartz solid solution phase.

[0171] In this embodiment, the second region 102 includes one or more of lithium silicate phase, lithium disilicate phase, and spodumene phase, as well as one or more of quartz phase, quartz solid solution phase, and spodumene phase. Combinations of the quartz phase, quartz solid solution phase, and / or spodumene phase with one or more of the lithium silicate phase, lithium disilicate phase, and spodumene phase are beneficial for increasing the second haze H2 of the second region 102 and widening the haze difference between the first region 101 and the second region 102.

[0172] In some embodiments of this application, the types of crystal phases in the first region 101 and the second region 102 are the same; in other embodiments, the types of crystal phases in the first region 101 and the second region 102 are different; in some embodiments, the second region 102 contains more types of crystal phases than the first region 101, for example, the second region 102 contains 3 or 4 types of crystal phases, while the first region 101 contains 2 types of crystal phases; or, for example, the second region 102 contains 4 types of crystal phases, while the first region 101 contains 3 types of crystal phases. The second region 102 containing more types of crystal phases is more conducive to controlling the haze difference between the first region 101 and the second region 102.

[0173] In some embodiments, the crystalline phase in the first region 101 includes a lithium disilicate phase and a petalite phase; or, the crystalline phase in the first region 101 includes a lithium silicate phase, a lithium disilicate phase, and a petalite phase; or, the crystalline phase in the first region 101 includes a lithium silicate phase; or, the crystalline phase in the first region 101 includes a lithium silicate phase and a petalite phase; the crystalline phase in the second region 102 includes a lithium disilicate phase, a petalite phase, and a quartz phase; or, the crystalline phase in the second region 102 includes a lithium disilicate phase, a petalite phase, and a quartz phase. The first region 101 contains no quartz phase, quartz solid solution phase, or spodumene phase; or, the crystalline phases in the second region 102 include lithium silicate phase, quartz solid solution phase, and spodumene phase; or, the crystalline phases in the second region 102 include lithium disilicate phase, quartz solid solution phase, and spodumene phase; or, the crystalline phases in the second region 102 include lithium disilicate phase, quartz solid solution phase, and spodumene phase. The absence of quartz phase, quartz solid solution phase, or spodumene phase in the first region 101 is beneficial for achieving lower haze in the first region. By controlling the different crystalline phases contained in the first region 101 and the second region 102, microcrystalline glass with different haze differences can be obtained to meet different application requirements.

[0174] In some embodiments, the crystalline phase in the first region 101 includes a lithium disilicate phase, a petalite phase, and a quartz phase; or, the crystalline phase in the first region 101 includes a lithium silicate phase and a quartz solid solution phase; or, the crystalline phase in the first region 101 includes a lithium disilicate phase and a quartz solid solution phase; the crystalline phase in the second region 102 includes a lithium disilicate phase, a petalite phase, and a quartz phase; or, the crystalline phase in the second region 102 includes a lithium disilicate phase, a petalite phase, a quartz phase, and a spodumene phase; or, the crystalline phase in the second region 102 includes a quartz solid solution phase and a spodumene phase. The presence of a quartz phase, a quartz solid solution phase, or a spodumene phase in the first region 101 is beneficial for achieving higher haze in the first region 101. By controlling the different crystalline phases contained in the first region 101 and the second region 102, microcrystalline glass with different haze differences can be obtained to meet different application requirements.

[0175] In one embodiment of this application, the crystalline phase 12 in the first region 101 and the crystalline phase 22 in the second region 102 both include lithium disilicate phase, lithium feldspar phase, and quartz phase. The inclusion of the quartz phase in both the first region 101 and the second region 102 is beneficial for maintaining both the first haze H1 and the second haze H2 at relatively high values.

[0176] In another embodiment of this application, the crystalline phase 12 in the first region 101 includes a lithium disilicate phase and a petalite phase, and the crystalline phase 22 in the second region 102 includes a lithium disilicate phase, a petalite phase, and a quartz phase. The inclusion of a quartz phase in the second region 102 is beneficial for improving the second haze H2 of the second region 102.

[0177] In some embodiments of this application, the crystalline phase 12 in the first region 101 includes a lithium silicate phase and a petalite phase, and the crystalline phase 22 in the second region 102 includes a lithium disilicate phase, a petalite phase, and a quartz phase. The inclusion of a quartz phase in the second region 102 is beneficial for improving the second haze H2 of the second region 102.

[0178] In some embodiments of this application, the crystalline phase 12 in the first region 101 includes a lithium silicate phase, a lithium disilicate phase, and a petalite phase, and the crystalline phase 22 in the second region 102 includes a lithium disilicate phase, a petalite phase, and a quartz phase. The inclusion of a quartz phase in the second region 102 is beneficial for improving the second haze H2 of the second region 102.

[0179] In some embodiments of this application, the crystalline phase 12 in the first region 101 includes a lithium disilicate phase, a petalite phase, and a quartz phase, and the crystalline phase 22 in the second region 102 includes a lithium disilicate phase, a petalite phase, a quartz phase, and a spodumene phase. The inclusion of the quartz phase and the spodumene phase in the second region 102 is beneficial for improving the second haze H2 of the second region 102.

[0180] In some embodiments of this application, the crystalline phase 12 in the first region 101 includes a lithium disilicate phase and a petalite phase, and the crystalline phase 22 in the second region 102 includes a lithium disilicate phase, a petalite phase, a quartz phase, and a spodumene phase. The inclusion of a quartz phase and a spodumene phase in the second region 102 is beneficial for improving the second haze H2 of the second region 102.

[0181] In some embodiments of this application, the crystalline phase 12 in the first region 101 includes a lithium silicate phase, and the crystalline phase 22 in the second region 102 includes a lithium silicate phase, a quartz solid solution phase, and a spodumene phase. The first region 101 includes only the lithium silicate phase, which is beneficial for obtaining low haze, while the second region 102 includes a quartz solid solution phase and a spodumene phase, which is beneficial for improving the second haze H2 of the second region 102.

[0182] In some embodiments of this application, the crystalline phase 12 in the first region 101 includes a lithium silicate phase and a quartz solid solution phase, and the crystalline phase 22 in the second region 102 includes a quartz solid solution phase and a spodumene phase. The inclusion of the spodumene phase in the second region 102 is beneficial for improving the second haze H2 of the second region 102.

[0183] In some embodiments of this application, the crystalline phase 12 in the first region 101 includes a lithium silicate phase, a lithium disilicate phase, and a petalite phase, and the crystalline phase 22 in the second region 102 includes a lithium disilicate phase, a petalite phase, and a spodumene phase. The inclusion of the spodumene phase in the second region 102 is beneficial for improving the second haze H2 of the second region 102.

[0184] In some embodiments of this application, the crystalline phase 12 in the first region 101 includes a lithium disilicate phase and a petalite phase, and the crystalline phase 22 in the second region 102 includes a lithium disilicate phase, a petalite phase, and a quartz solid solution phase. The inclusion of a quartz solid solution phase in the second region 102 is beneficial for improving the second haze H2 of the second region 102.

[0185] In some embodiments of this application, the crystalline phase 12 in the first region 101 includes a lithium disilicate phase and a petalite phase, and the crystalline phase 22 in the second region 102 includes a lithium disilicate phase, a petalite phase, a quartz solid solution phase, and a spodumene phase. The inclusion of a quartz solid solution phase and a spodumene phase in the second region 102 is beneficial for improving the second haze H2 of the second region 102.

[0186] In some embodiments of this application, the crystalline phase 12 in the first region 101 includes a lithium disilicate phase and a quartz solid solution phase, and the crystalline phase 22 in the second region 102 includes a quartz solid solution phase and a spodumene phase. The inclusion of the spodumene phase in the second region 102 is beneficial for improving the second haze H2 of the second region 102.

[0187] In some embodiments of this application, the crystalline phase 12 in the first region 101 includes a lithium silicate phase and a petalite phase, and the crystalline phase 22 in the second region 102 includes a lithium disilicate phase, a petalite phase, and a quartz solid solution phase. The inclusion of a quartz solid solution phase in the second region 102 is beneficial for improving the second haze H2 of the second region 102.

[0188] In some embodiments of this application, the sum of the mass percentages of the quartz phase, quartz solid solution phase, and spodumene phase in the second region 102 is greater than the sum of the mass percentages of the quartz phase, quartz solid solution phase, and spodumene phase in the first region 101. Higher contents of the quartz phase, quartz solid solution phase, and spodumene phase are more conducive to improving haze; therefore, this design is beneficial for widening the haze difference between the first region 101 and the second region 102.

[0189] In this embodiment, the sum of the mass percentages of the quartz phase, quartz solid solution phase, and spodumene phase in the second region 102 is greater than or equal to 5%. Higher contents of these three phases are more beneficial for improving the haze of the second region 102. In some embodiments, the sum of the mass percentages of the quartz phase, quartz solid solution phase, and spodumene phase in the second region 102 is 5%, 8%, 10%, 12%, or 15%.

[0190] In this application, the total mass percentage of the crystalline phase 12 in the first region 101 and the total mass percentage of the crystalline phase 22 in the second region 102 can be the same or different. In some embodiments of this application, the total mass percentage of the crystalline phase 22 in the second region 102 is greater than the total mass percentage of the crystalline phase 12 in the first region 101. A larger total mass percentage of the crystalline phase 22 in the second region 102 is more conducive to controlling the haze difference between the first region 101 and the second region 102. In some embodiments, the difference between the total mass percentage of the crystalline phase 22 in the second region 102 and the total mass percentage of the crystalline phase 12 in the first region 101 is greater than 1%; for example, 2%, 5%, 7%, 9%, 10%, 15%, 20%, 30%, and 40%.

[0191] In some embodiments of this application, the total mass percentage of the crystalline phase 12 in the first region 101 is greater than or equal to 15%. For example, the total mass percentage of the crystalline phase 12 in the first region 101 can be 15%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, or 90%. In some embodiments, the total mass percentage of the crystalline phase 12 in the first region 101 is greater than or equal to 90%. For fine grains, a high total content of the crystalline phase 12 in the first region 101 is beneficial for improving the mechanical properties of the glass-ceramic 100, such as strength and toughness.

[0192] In some embodiments of this application, the total mass percentage of the crystalline phase 22 in the second region 102 is greater than or equal to 30%. For example, the total mass percentage of the crystalline phase 22 in the second region 102 can be 30%, 40%, 45%, 50%, 60%, 70%, 80%, or 90%. In some embodiments, the total mass percentage of the crystalline phase 22 in the second region 102 is greater than or equal to 40%. In some embodiments, the total mass percentage of the crystalline phase 22 in the second region 102 is greater than or equal to 90%. For fine grains, a high total content of the crystalline phase 22 in the second region 102 is beneficial for improving the haze of the second region 102, and also beneficial for improving the mechanical properties of the glass-ceramic 100, such as strength and toughness.

[0193] The types and contents of crystal phases in the microcrystalline glass 100 can be characterized by XRD (X-ray diffraction).

[0194] The microcrystalline glass 100 of this application embodiment may contain bubbles, cracks, etc., in addition to the glass phase and crystalline phase. These bubbles and cracks are unavoidably generated during the process, i.e., passively generated. The distribution of bubbles and cracks in the first region 101 and the second region 102 is basically the same. The porosity of the microcrystalline glass 100 of this application can be below 2% (volume fraction).

[0195] In some embodiments of this application, the average crystal size in the second region 102 is larger than the average crystal size in the first region 101. A larger average crystal size in the second region 102 is more advantageous for controlling the haze difference between the first region 101 and the second region 102. In some embodiments, the average crystal size in the second region 102 is greater than or equal to 1.5 times the average crystal size in the first region 101. In some embodiments, the average crystal size in the second region 102 is 2 to 50 times the average crystal size in the first region 101.

[0196] In some embodiments of this application, the average crystal size in the first region 101 is 10 nm to 150 nm. Exemplarily, the average crystal size in the first region 101 is 10 nm, 20 nm, 30 nm, 40 nm, 50 nm, 60 nm, 70 nm, 80 nm, 90 nm, 100 nm, 110 nm, 120 nm, 130 nm, 140 nm, or 150 nm. The smaller grain size of the crystal phase in the first region 101 is beneficial for reducing the haze of the first region 101 and improving the mechanical properties of the glass-ceramic 100, such as its strength.

[0197] In some embodiments of this application, the average crystal size in the second region 102 is 50 nm to 2000 nm. Exemplarily, the average crystal size in the second region 102 is 50 nm, 60 nm, 90 nm, 100 nm, 150 nm, 200 nm, 250 nm, 300 nm, 400 nm, 500 nm, 600 nm, 700 nm, 800 nm, 900 nm, 1000 nm, 1100 nm, 1200 nm, 1300 nm, 1400 nm, 1500 nm, 1600 nm, 1800 nm, or 2000 nm. The relatively larger grain size of the crystal phase in the second region 102 is beneficial for widening the haze difference between the first region 101 and the second region 102. Simultaneously, within this suitable range, it is beneficial for ensuring that the mechanical properties of the glass-ceramic 100, such as strength, are at a high level.

[0198] The crystal size can be characterized using SEM (Scanning Electron Microscope).

[0199] In some embodiments of this application, the second region 102 contains more types of crystal phases than the first region 101; and / or, the total mass percentage of crystal phases in the second region 102 is greater than the total mass percentage of crystal phases in the first region 101; and / or, the average crystal size in the second region 102 is greater than the average crystal size in the first region 101.

[0200] In some embodiments of this application, the first haze H1 is in the range of 0 to 20%. For example, the first haze H1 is 0.1%, 0.15%, 0.16%, 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, 0.8%, 0.9%, 1%, 1.2%, 1.4%, 1.5%, 1.8%, 1%, 2%, 2.5%, 3%, 4%, 4.5%, 5%, 6%, 7%, 8%, 9%, 10%, 11%, 12%, 13%, 14%, 15%, 16%, 17%, 18%, 19%, or 20%.

[0201] In some embodiments of this application, the second haze H2 is in the range of 8% to 95%. Exemplarily, the second haze H2 is 8%, 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, or 95%.

[0202] In some embodiments of this application, the difference between the first haze H1 and the second haze H2 (i.e., H2-H1) is greater than or equal to 8%. Exemplarily, the difference between the first haze H1 and the second haze H2 (i.e., H2-H1) is greater than or equal to 8%, or greater than or equal to 10%, or greater than or equal to 15%, or greater than or equal to 20%, or greater than or equal to 25%, or greater than or equal to 30%, or greater than or equal to 35%, or greater than or equal to 40%, or greater than or equal to 45%, or greater than or equal to 50%, or greater than or equal to 55%, or greater than or equal to 60%, or greater than or equal to 65%, or greater than or equal to 70%, or greater than or equal to 75%.

[0203] LAB values ​​are the three elements of color space coordinates. L value represents brightness, with L = 0 for black and L = 100 for white (the brightest value). A value represents reddish-green tint; a positive A value indicates red, and a negative A value indicates green. B value represents yellowish-blue tint; a positive B value indicates yellow, and a negative B value indicates blue. Larger values ​​indicate deeper color intensity. In this embodiment, when the microcrystalline glass 100 has a thickness of 0.3mm to 0.7mm, in transmittance mode testing, the L value of the first region 101 is 40 to 99, the A value is -100 to 100, and the B value is -100 to 100; the L value of the second region 102 is 20 to 95, the A value is -100 to 100, and the B value is -100 to 100. For example, the L value of the first region 101 can be 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 99; the A value can be -100, -80, -70, -60, -50, -20, -10, 0, 0.01, 0.05, 0.1, 0.2, 0.5, 1, 10, 20, 30, 40, 50, 60, 70, 80, 90, 100; and the B value can be -100, -80, -70, -60, -50, -20, -10, 0, 0.01, 0.05, 0.1, 0.2, 0.5, 1, 10, 20, 30, 40, 50, 60, 70, 80, 90, 100. For example, the L value of the second region 102 can be 20, 30, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95; the A value can be -100, -80, -70, -60, -50, -20, -10, 0, 0.01, 0.05, 0.1, 0.2, 0.5, 1, 10, 20, 30, 40, 50, 60, 70, 80, 90, 100; and the B value can be -100, -80, -70, -60, -50, -20, -10, 0, 0.01, 0.05, 0.1, 0.2, 0.5, 1, 10, 20, 30, 40, 50, 60, 70, 80, 90, 100.

[0204] Referring to Figures 3 and 4, Figure 3 is a cross-sectional schematic diagram of the microcrystalline glass 100 provided in another embodiment of this application; Figure 4 is a schematic diagram of the different region distributions of the microcrystalline glass 100 provided in another embodiment of this application. In this embodiment, the microcrystalline glass 100 further includes a third region 103 located between the first region 101 and the second region 102, and the haze of the third region 103 gradually increases from the first region 101 to the second region 102. Specifically, it can be a gradual change from a first haze H1 or a haze close to the first haze H1 to a second haze H2 or a haze close to the second haze H2.

[0205] The introduction of the third region 103 helps the microcrystalline glass 100 to achieve richer haze variation effects, which can improve the user experience when used in electronic device cover plates and other fields.

[0206] It should be noted that the dashed lines in Figures 1 to 4 are for illustrative purposes only and do not exist in the actual products.

[0207] In this embodiment of the application, the third region 103 includes a glass phase 31 and a crystalline phase 32. The crystalline phase 32 in the third region 103 may be one or more of lithium silicate phase, lithium disilicate phase and lithite phase, as well as one or more of quartz phase, quartz solid solution phase and spodumene phase.

[0208] For example, the crystalline phase 32 in the third region 103 may include a lithium disilicate phase, a spodumene phase, and a quartz phase. Alternatively, the crystalline phase 32 in the third region 103 may include a lithium silicate phase, a lithium disilicate phase, a spodumene phase, and a quartz phase. Alternatively, the crystalline phase 32 in the third region 103 may include a lithium disilicate phase, a spodumene phase, a quartz phase, and a spodumene phase.

[0209] In some embodiments of this application, in the third region 103 from the first region 101 to the second region 102, the sum of the mass percentages of the quartz phase, the quartz solid solution phase, and the spodumene phase gradually increases; or the total mass percentage of the crystalline phase gradually increases; or the average crystal size gradually increases; or the number of crystal types increases.

[0210] In this embodiment of the application, the LAB value of the third region 103 is between the LAB value of the first region 101 and the LAB value of the second region 102, and gradually changes from the first region 101 to the second region 102.

[0211] In this application, the glass-ceramic 100 can be a lithium aluminum silicon-based glass-ceramic, and the components of the glass-ceramic 100 include Li2O, SiO2, and Al2O3. In some embodiments of this application, the mass percentages of Li2O, SiO2, and Al2O3 in the glass-ceramic 100 satisfy 4 ≤ (Li2O + SiO2) / Al2O3 ≤ 25. In this application, by controlling the mass percentages of Li2O, SiO2, and Al2O3 in the glass-ceramic 100 to meet the above-mentioned specific ratio, it is beneficial for the glass-ceramic 100 to have the ability to precipitate crystalline phases with large optical haze variations, thereby achieving the control of the haze of the first region 101 and the second region 102. The glass-ceramic 100 may precipitate lithium silicate, lithium disilicate, and petalite phases with relatively small crystals and refractive indices not much different from the glass phase, resulting in lower haze. It may also precipitate quartz phases and quartz solid solution phases with moderate refractive indices and relatively larger crystals. These crystalline phases, combined with lithium silicate, lithium disilicate, and petalite, can widen the haze range of the glass-ceramic. It may also precipitate spodumene phase with a large refractive index difference from the glass phase. The coarse crystals of the spodumene phase can further expand the haze range of the glass-ceramic 100.

[0212] For example, the mass percentage of Li2O, SiO2, and Al2O3 in the glass-ceramic 100 (Li2O+SiO2) / Al2O3 can be 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, or 25. In some embodiments of this application, 6 ≤ (Li2O+SiO2) / Al2O3 ≤ 15. In some embodiments of this application, 10 ≤ (Li2O+SiO2) / Al2O3 ≤ 20.

[0213] Controlling the relative contents of Li₂O and Al₂O₃ in the glass-ceramic 100 is beneficial for regulating the ratio of lithium silicate, lithium disilicate, litharge, quartz phase, and quartz solid solution phase, as well as the chemically enhanced ion exchange capacity of the glass-ceramic 100. In some embodiments of this application, the mass percentages of Li₂O and Al₂O₃ in the glass-ceramic 100 satisfy 0.5 ≤ Li₂O / Al₂O₃ ≤ 5. By controlling the relative content of Li₂O and Al₂O₃ within the aforementioned suitable range, the lithium silicate, lithium disilicate, petalite, quartz phase, and quartz solid solution phase in the glass-ceramic 100 can be made to have suitable contents. This allows the glass-ceramic 100 to obtain good optical properties and good ion exchange capacity. It also provides the glass-ceramic 100 with a larger space for subsequent heating, which is conducive to forming different regions with obvious differences in optical characteristics (including haze, LAB, etc.) (such as the first region 101 and the second region 102), and also conducive to forming intermediate transition regions with continuous haze changes and good gradient effects (such as the third region 103). For example, the Li₂O / Al₂O₃ ratio can be 0.5, 0.6, 0.7, 0.8, 0.9, 1, 1.2, 1.5, 1.8, 2, 2.2, 2.5, 3, 3.5, 4, 4.5, or 5. In some embodiments, 0.9 ≤ Li₂O / Al₂O₃ ≤ 2.5.

[0214] In some embodiments of this application, the microcrystalline glass 100 may comprise the following components in weight percentage:

[0215] Li2O: 5%–20%,

[0216] SiO2: 50%–85%,

[0217] Al2O3: 4%–15%,

[0218] P2O5: 0.5%–5%,

[0219] ZrO2: 2%–10%,

[0220] TiO2: 0-5%,

[0221] Na2O: 0-5%,

[0222] K2O: 0-5%,

[0223] B2O3: 0-5%,

[0224] Coloring component: 0-5%.

[0225] Li₂O is an essential component of the crystalline phases in the glass-ceramic 100, and also a necessary component for chemical strengthening. Li₂O helps to form lithium-containing crystalline phases such as lithium silicate and petalite, and to obtain better ion exchange capacity. However, excessive Li₂O may lead to a decrease in the chemical stability and a deterioration in the transmittance of the glass-ceramic. Taking into account the above effects, in the embodiments of this application, the mass percentage of Li₂O is controlled within the range of 5% to 20%. For example, the mass percentage of Li2O in the glass-ceramic 100 can be 5%, 5.5%, 6%, 6.5%, 7%, 7.5%, 8%, 8.5%, 9%, 9.5%, 10%, 10.5%, 11%, 11.5%, 12%, 12.5%, 13%, 13.5%, 14%, 14.5%, 15%, 15.5%, 16%, 16.5%, 17%, 17.5%, 18%, 18.5%, 19%, 19.5%, or 20%. In some embodiments, the mass percentage of Li2O is controlled within the range of 5% to 15%.

[0226] Al2O3 is an intermediate oxide in the formation of the glass-ceramic 100, which can improve the chemical stability of the glass-ceramic 100. Furthermore, since [AlO4] has a larger volume than [SiO4], it provides more space for ion exchange; therefore, alumina can promote ion exchange. Increased Al2O3 content tends to increase the viscosity of the glass-ceramic, and the presence of alkaline earth metals further increases the tendency for crystallization. Considering chemical stability, viscosity, and ion exchange capacity, the embodiments of this application control the mass percentage of Al2O3 to 4%–15%. Exemplarily, the mass percentage of Al2O3 in the glass-ceramic 100 is 4%, 4.5%, 5%, 5.5%, 6%, 6.5%, 7%, 7.5%, 8%, 8.5%, 9%, 9.5%, 10%, 10.5%, 11%, 11.5%, 12%, 12.5%, 13%, 13.5%, 14%, 14.5%, and 15%. In some implementations, the mass percentage of Al2O3 is 5% to 10%.

[0227] SiO2 is a fundamental component in the formation of the glass-ceramic 100, used to stabilize its network structure. It is also one of the components forming the lithium silicate phase, quartz phase, and lithite phase. When the mass percentage of SiO2 is below 50%, the number of crystalline phases formed in the glass-ceramic 100 decreases, the crystals become coarser, and the haze and impact resistance (e.g., drop ball test height) of the glass-ceramic decrease. When the mass percentage of SiO2 is above 85%, the melting temperature of the glass-ceramic increases, making it difficult to form and affecting the consistency of the glass. Considering the above effects, the embodiments of this application control the mass percentage of SiO2 between 50% and 85%. Exemplarily, the mass percentage of SiO2 in the glass-ceramic 100 is 50%, 55%, 60%, 65%, 70%, 72%, 75%, 78%, 80%, and 85%. In some embodiments, the mass percentage of SiO2 is 50% to 78%. In other embodiments, the mass percentage of SiO2 is 50% to 75%.

[0228] ZrO2 is an intermediate oxide in the formation of glass-ceramics 100. It can improve the chemical stability of glass-ceramics, increase their hardness, scratch resistance, and drop resistance. Simultaneously, due to its high cation charge and strong field, ZrO2 has a significant accumulation effect on the glass-ceramic structure and can act as a nucleating agent. However, the introduction of a large amount of ZrO2 increases the viscosity of the glass-ceramics, affecting their molding ability. Considering the above effects, in the Li2O-Al2O3-SiO2 system glass-ceramics of this application embodiment, the mass percentage of ZrO2 is controlled at 2% to 10%. Exemplarily, the mass percentage of ZrO2 in the glass-ceramics 100 is 2%, 2.5%, 3%, 3.5%, 4%, 4.5%, 5%, 5.5%, 6%, 6.5%, 7%, 7.5%, 8%, 8.5%, 9%, 9.5%, and 10%.

[0229] P2O5 helps improve the low-temperature melting properties of glass-ceramics, enables phase separation and crystal nucleation within the glass-ceramic, and enhances the thermal expansion stability of the glass-ceramic during crystallization. However, excessive P2O5 may lead to a decrease in the mechanical properties and transmittance of the glass-ceramic, and increase the risk of phase separation. Considering the above effects, in the embodiments of this application, the mass percentage of P2O5 is controlled between 0.5% and 5%. For example, the mass percentage of P2O5 in the glass-ceramic 100 is 0.5%, 0.8%, 0.9%, 1%, 1.5%, 2%, 2.5%, 3%, 3.5%, 4%, 4.5%, and 5%.

[0230] B2O3, as a flux in the formation process of glass-ceramics, can reduce the high-temperature viscosity of glass-ceramics, accelerate the clarification of glass-ceramics, and reduce the crystallization ability of glass-ceramics. However, excessive B2O3 will reduce the chemical stability and mechanical strength of glass-ceramics. Taking into account the above effects, in the embodiments of this application, the mass percentage of B2O3 is controlled between 0% and 5%. For example, the mass percentage of B2O3 in glass-ceramics 100 is 0%, 0.1%, 0.4%, 0.5%, 0.8%, 0.9%, 1%, 1.5%, 2%, 2.5%, 3%, 3.5%, 4%, 4.5%, and 5%.

[0231] K₂O helps improve the low-temperature melting and formability of glass-ceramics, but excessive K₂O may reduce the chemical stability of the glass-ceramics and increase the average coefficient of linear expansion. Considering these effects, in this embodiment, the mass percentage of K₂O is controlled between 0% and 5%. For example, the mass percentage of K₂O in the glass-ceramic 100 is 0%, 0.1%, 0.4%, 0.5%, 0.8%, 0.9%, 1%, 1.5%, 2%, 2.5%, 3%, 3.5%, 4%, 4.5%, and 5%.

[0232] Na₂O, as an external oxide in the network formation of glass-ceramics, can improve the viscosity of glass-ceramics, promote the melting and clarification of the glass melt, and also enhance ion exchange capacity through ion exchange with the molten salt bath. However, excessive Na₂O can reduce the chemical stability of glass-ceramics and increase the average coefficient of linear expansion. In the embodiments of this application, the mass percentage of Na₂O is controlled between 0% and 5%. Exemplarily, the mass percentage of Na₂O in glass-ceramics 100 is 0%, 0.1%, 0.4%, 0.5%, 0.8%, 0.9%, 1%, 1.5%, 2%, 2.5%, 3%, 3.5%, 4%, 4.5%, and 5%.

[0233] TiO2 helps lower the melting temperature and improve the chemical stability of glass-ceramics. Controlling the mass percentage of TiO2 in the glass-ceramic 100 within the range of 0% to 5% makes the crystallization process easier to control. For example, the mass percentage of TiO2 in the glass-ceramic 100 is 0%, 0.1%, 0.4%, 0.5%, 0.8%, 0.9%, 1%, 1.5%, 2%, 2.5%, 3%, 3.5%, 4%, 4.5%, and 5%.

[0234] In this embodiment, the microcrystalline glass 100 includes P2O5 and ZrO2, and may or may not include TiO2. Through extensive experimentation, the inventors have discovered that the ratio of (SiO2+Al2O3) / (P2O5+TiO2+ZrO2) affects the size of the crystal phases, thus influencing optical properties and the melting process. In this embodiment, controlling the ratio within the range of 4≤(SiO2+Al2O3) / (P2O5+TiO2+ZrO2)≤30 is beneficial for the smooth progress of the melting process, for controlling the formation of coarse crystals, for improving the overall optical performance uniformity of the microcrystalline glass 100, and for enhancing the continuity of the haze gradient effect. For example, the ratio of (SiO2+Al2O3) / (P2O5+TiO2+ZrO2) is 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30. In some embodiments of this application, 8 ≤ (SiO2+Al2O3) / (P2O5+TiO2+ZrO2) ≤ 16.

[0235] The microcrystalline glass of this application embodiment, through the synergistic effect of the above-mentioned components, can achieve a large haze difference in appearance on the same piece of microcrystalline glass without introducing additional operations, and can be chemically strengthened to obtain a large compressive stress layer depth, a better stress value, and a higher compressive strength.

[0236] In this embodiment, the coloring component can be one or more elemental or oxide coloring elements, including Au, Ag, Cu, Ni, Co, Fe, Mn, Cr, V, Ti, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu. By doping with small amounts of coloring elements, such as iron (Fe) to form olive green, chromium (Cr) to form green, cobalt (Co) to form deep blue, vanadium (V) to form yellow, copper (Cu) to form red, gold (Au) to form pink, and silver (Ag) to form yellowish-brown, etc., the coloring component is exemplarily Au, Cr2O, Co3O4, Cu2O, etc. Too high a content of the coloring component will affect the presentation of the haze gradient effect. In this embodiment, the mass percentage of the coloring component is controlled between 0% and 5%. For example, the mass percentage of the coloring component in the microcrystalline glass 100 is 0%, 0.1%, 0.4%, 0.5%, 0.8%, 0.9%, 1%, 1.5%, 2%, 2.5%, 3%, 3.5%, 4%, 4.5%, and 5%.

[0237] The microcrystalline glass 100 of this application embodiment may also include some unavoidable impurity components, the mass percentage of which is less than or equal to 5%, for example, it can be 0, 0.5%, 1%, 1.5%, 2%, 2.5%, 3%, 3.5%, 4%, 4.5%, or 5%.

[0238] The components and contents of the microcrystalline glass 100 can be characterized by XRF (X-ray Fluorescence Spectrometer).

[0239] The thickness of the microcrystalline glass 100 can be designed according to actual needs, for example, it can be 0.3mm to 0.7mm. Specifically, for example, 0.3mm, 0.4mm, 0.5mm, 0.6mm, and 0.7mm.

[0240] In this embodiment of the application, the glass-ceramic 100 can be either a non-chemically strengthened glass-ceramic or a chemically strengthened glass-ceramic.

[0241] Among them, chemically strengthened glass-ceramics have a compressive stress layer and a tensile stress layer corresponding to the compressive stress layer.

[0242] In this application, the average tensile stress of the chemically strengthened glass-ceramic is greater than 30 MPa. The average tensile stress (CT-Av) is the average tensile stress in the tensile stress region of the glass-ceramic. In some embodiments of this application, the average tensile stress of the chemically strengthened glass-ceramic is between 32 MPa and 87 MPa. Specifically, the average tensile stress can be, for example, 32 MPa, 35 MPa, 39 MPa, 40 MPa, 45 MPa, 60 MPa, 65 MPa, 70 MPa, 75 MPa, 80 MPa, 85 MPa, or 87 MPa. A suitable average tensile stress is beneficial for the glass-ceramic to possess high strength while preventing excessively small fragments after failure and breakage.

[0243] In this embodiment, the compressive stress layer depth (DOC) of the chemically strengthened glass-ceramic is greater than 70 μm. In some embodiments, the compressive stress layer depth is greater than or equal to 80 μm; in some embodiments, the compressive stress layer depth is greater than or equal to 90 μm; in some embodiments, the compressive stress layer depth is greater than or equal to 100 μm; in some embodiments, the compressive stress layer depth is greater than or equal to 110 μm. In some embodiments, the compressive stress layer depth is 80 μm-120 μm.

[0244] In this embodiment, the compressive stress CS50 at a depth of 50 μm in the compressive stress layer of the chemically strengthened glass-ceramic is ≥40 MPa. CS50 is the compressive stress value at a depth of 50 μm from the surface of the chemically strengthened glass-ceramic. CS50 ≥40 MPa ensures high strength of the glass-ceramic. The higher the CS50 value, the better the drop resistance of the glass-ceramic. In some embodiments, CS50 ≥50 MPa. In some embodiments, CS50 ≥60 MPa. In some embodiments, CS50 ≥70 MPa. In some embodiments, CS50 ≥90 MPa. In some embodiments, CS50 ≥100 MPa. In other embodiments, CS50 ≥130 MPa. In still other embodiments, CS50 ≥150 MPa.

[0245] The above-mentioned average tensile stress CT-Av, compressive stress layer depth DOC, and compressive stress CS50 can be measured using a stress meter (such as SLP2000 or FSM6000).

[0246] In this embodiment, the compressive strength of the chemically strengthened glass-ceramic is greater than 10 kgf. Exemplarily, the compressive strength of the chemically strengthened glass-ceramic is 11 kgf, 13 kgf, 15 kgf, 16 kgf, 17 kgf, 18 kgf, 20 kgf, 22 kgf, 25 kgf, 27 kgf, and 30 kgf. The compressive strength can be tested using a universal testing machine. Specifically, the test can be performed by using a stainless steel ball head with a 10 mm radius of curvature to compress the center of the glass-ceramic at a speed of 10 mm / min until it cracks, and recording the maximum force, which is the compressive strength.

[0247] This application embodiment also provides a method for preparing the above-mentioned microcrystalline glass 100, including:

[0248] S101. After melting and molding the raw materials of each component of the microcrystalline glass, a glass to be crystallized is obtained; the glass to be crystallized includes a first crystallization region and a second crystallization region;

[0249] S102. The glass to be crystallized obtained in step S101 is heated and crystallized to obtain microcrystalline glass 100; wherein, the heating and crystallization includes at least one non-uniform heating and crystallization, which is to provide different thermal fields to the first region to be crystallized and the second region to be crystallized for heating respectively.

[0250] The resulting glass-ceramic 100 includes a first region 101 and a second region 102, wherein a first region to be crystallized is used to form the first region 101, and a second region to be crystallized is used to form the second region 102. Both the first region 101 and the second region 102 include a glass phase and a crystalline phase. The first region 101 has a first haze, and the second region 102 has a second haze greater than the first haze. The difference between the first haze and the second haze is greater than or equal to 8%. The first haze and the second haze are measured when the roughness Ra of the two side surfaces of the first region 101 and the second region 102 of the glass-ceramic 100 is ≤100 nm.

[0251] In step S101, the raw materials corresponding to each component of the microcrystalline glass can be various forms of materials available in the glass manufacturing field, as long as they can provide the above-mentioned components. For example, the aforementioned SiO2 can be silica sand, the aforementioned Al2O3 can be cerium monoxide, alumina, aluminum hydroxide, etc., the aforementioned Na2O can be Na2CO3, and the aforementioned ZrO2 can be ZrO2, zirconium silicate, etc.

[0252] Melting involves melting various raw materials to form molten glass. The melting temperature can be between 1300℃ and 1600℃, for example, 1300℃, 1350℃, 1400℃, 1450℃, 1500℃, 1550℃, 1600℃, etc. Forming is the process of transforming the molten glass into an article with a specific geometric shape. Forming methods may include, but are not limited to, casting, calendering, float glass, overflow forming, and slotted / up / down forming. This forming process can create glass blocks or sheets to be crystallized. After melting and forming, the glass is cooled to room temperature.

[0253] In step S102, during the heating and crystallization process, the glass to be crystallized becomes microcrystalline, and a microcrystalline phase grows inside. After crystallization, it undergoes cold processing steps such as wire cutting, thinning, and polishing to obtain 2D or 2.5D shaped microcrystalline glass.

[0254] Heating crystallization can be carried out in a heating furnace, such as a box furnace or tunnel furnace. In some embodiments, the heating operation during heating crystallization may include heating at 400℃-800℃ for 0.5h-8h. In other embodiments, the heating operation sequentially includes: heating from room temperature to 600℃ for 6h-10h, nucleation at 500℃-600℃ for 2h-6h, crystallization growth at 600℃-800℃ for 1h-3h, and cooling from 800℃ to room temperature for 4h to 12h or more. In still other embodiments, the heating operation sequentially includes: heating from room temperature to 600℃ for 10min, crystallization at 600℃-900℃ for 10min-180min, and cooling from 800℃ to room temperature for 1h to 24h.

[0255] In some embodiments of this application, during the non-uniform heating crystallization process, a heat insulation element can be used to shield the first region to be crystallized, while the second region to be crystallized remains unshielded, thus providing different thermal fields to the first and second regions. In the same heating operation, the first region to be crystallized receives less heat than the second region, resulting in a high-temperature thermal field for the second region and a low-temperature thermal field for the first region. This leads to a difference in the crystallization results between the two regions; specifically, the haze in the region corresponding to the high-temperature thermal field is greater than that in the region corresponding to the low-temperature thermal field. The temperature difference between the different thermal fields can be set as needed, for example, it can be greater than or equal to 30°C. At the boundary between the first and second regions to be crystallized, due to the mutual influence of the thermal fields on both sides, a third region connecting the first and second regions can be formed. That is, a local area of ​​the first region to be crystallized adjacent to the second region, and a local area of ​​the second region to be crystallized adjacent to the first region, together form the third region.

[0256] Referring to Figures 5 and 6, Figure 5 is a schematic diagram of the heat insulation component arrangement in one embodiment of this application; Figure 6 is a schematic diagram of the heat insulation component arrangement in another embodiment of this application. In Figures 5 and 6, 100a is the first crystallization region of the glass to be crystallized, 100b is the second crystallization region of the glass to be crystallized, and 1 is the furnace body. Heat is transferred inside the furnace body through thermal radiation and thermal conduction.

[0257] In some embodiments of this application, as shown in FIG5, the heat insulation component may include a heat insulation mold 41 and a heat insulation filler 42 filled between the heat insulation mold 41 and the glass to be crystallized. The material of the heat insulation mold 41 may be a low thermal conductivity material with a thermal conductivity of <5W / mK, such as mullite, cordierite, etc., and the heat insulation filler 42 may be a low thermal conductivity material with a thermal conductivity of <5W / mK, such as quartz sand, heat insulation asbestos, aerogel, etc.

[0258] In other embodiments of this application, as shown in FIG6, the heat insulation component may include a heat insulation coating 43. The heat insulation coating 43 may be a low thermal conductivity material with a thermal conductivity of <5W / mK, such as cubic boron nitride, zirconium oxide, etc., and the thickness of the heat insulation coating 43 may be ≥20µm. The heat insulation coating 43 may be attached to the surface of the glass to be crystallized by means of scraping, plasma spraying, PVD, CVD, etc.

[0259] The aforementioned heating crystallization can include one or more non-uniform heating crystallization processes, and can further include one or more uniform heating crystallization processes. Uniform heating crystallization involves providing the same thermal field to both the first and second regions to be crystallized. Refer to Figure 7, which is a schematic diagram illustrating the provision of the same thermal field to both the first and second regions to be crystallized during uniform heating crystallization. In Figure 7, 100a represents the first region to be crystallized, 100b represents the second region to be crystallized, and 1 represents the furnace body. Neither the first nor the second region to be crystallized is equipped with heat insulation.

[0260] In this embodiment of the application, when preparing 3D glass-ceramic, step S102 further includes performing a hot bending process after completing the above-mentioned heating and crystallization and obtaining a glass-ceramic flat sheet through cutting, thinning, and polishing. This hot bending process can include uniform hot bending and / or non-uniform hot bending. Uniform hot bending provides the same thermal field to both the first and second regions to be crystallized during hot bending, while non-uniform hot bending provides different thermal fields to both regions. The hot bending process is performed in a hot bending machine. During the hot bending process, the glass-ceramic can achieve further crystallization under the action of the thermal field. Non-uniform hot bending allows different regions to achieve different crystallization processes.

[0261] Referring to Figure 8, Figure 8 is a schematic diagram illustrating the provision of the same thermal field to the first and second regions to be crystallized during the uniform thermal bending process according to an embodiment of this application. A thermal bending die with uniform thermal conductivity is used. The power of the heating elements and the cooling water flow rate are the same at different positions of the thermal bending machine.

[0262] Referring to Figures 9 to 14, which are schematic diagrams illustrating different methods of providing different thermal fields during the non-uniform thermal bending process according to embodiments of this application. In Figures 8 to 14, 2 represents the thermal bending machine, 50 represents the thermal bending mold, 100a represents the first region to be crystallized, and 100b represents the second region to be crystallized.

[0263] In some embodiments of this application, as shown in Figures 9 to 14, during the non-uniform thermal bending process, different thermal fields are provided to the first crystallization region 100a and the second crystallization region 100b, specifically as follows:

[0264] A hot bending die 50 with a non-uniform thermal conductivity is used. The thermal conductivity of the part of the hot bending die 50 corresponding to the first crystallization region 100a is less than the thermal conductivity of the part corresponding to the second crystallization region 100b.

[0265] As shown in Figure 9, in some embodiments, the hot bending die 50 includes a high thermal conductivity main material 50a and a second material 50b. The thermal conductivity of the second material 50b is lower than that of the main material 50a. In this embodiment, the second material 50b includes a low thermal conductivity material with a thermal conductivity ≤ 5 W / mK. The hot bending die 50 includes an upper die 51 and a lower die 52. At least one of the upper die 51 and the lower die 52, corresponding to the portion of the first crystallization region 100a, includes a layered high thermal conductivity main material and a low thermal conductivity second material. The portions of the upper die 51 and the lower die 52 corresponding to the second crystallization region 100b are both composed of the high thermal conductivity main material. Thus, the thermal field provided to the second crystallization region is a high thermal field, while the thermal field provided to the first crystallization region is a low thermal field. The high thermal conductivity base material includes materials with a thermal conductivity ≥40W / mK, such as graphite, silicon carbide, and tungsten steel, and low thermal conductivity materials with a thermal conductivity ≤5W / mK, such as one or more of mullite, cordierite, zirconium oxide, quartz, and aerogel. The hot bending die 50 can be a splicing die, and the splicing method can be sintering, overlapping, or inlaying.

[0266] As shown in Figure 10, in some embodiments, at least one of the upper die 51 and lower die 52 of the hot bending die 50 has a low thermal conductivity coating 53 on the surface corresponding to the first crystallization region 100a. The low thermal conductivity coating 53 can be a low thermal conductivity material including materials with a thermal conductivity ≤5W / mK, such as cubic boron nitride, zirconium oxide, etc., and the thickness of the low thermal conductivity coating 53 can be ≥20µm. The low thermal conductivity coating 53 can be attached to the surface of the hot bending die 50 by means of scraping, plasma spraying, PVD (physical vapor deposition), CVD (chemical vapor deposition), etc.

[0267] As shown in Figure 11, in some embodiments, the hot bending die 50 includes a high thermal conductivity main material 50a and a second material 50b, and at least one of the upper die 51 and the lower die 52 of the hot bending die 50 has a low thermal conductivity coating 53 on the surface corresponding to the portion of the first crystallization region 100a. In this embodiment, the second material 50b may be a material with a thermal conductivity of 0-100 W / mK, such as one or more of mullite, cordierite, zirconium oxide, quartz, aerogel, alumina, silicon carbide, and silicon nitride. In some embodiments, the low thermal conductivity coating 53 is disposed on the surface of the second material 50b.

[0268] In other embodiments of this application, as shown in Figures 12 to 14, during the non-uniform thermal bending process, different thermal fields are provided to the first crystallization region 100a and the second crystallization region 100b, specifically as follows:

[0269] Referring to Figure 12, a hot bending machine 2 with non-uniform power distribution of heating tubes is used. The power of the heating tubes in the hot bending machine 2 corresponding to the first crystallization region 100a is less than the power of the heating tubes in the second crystallization region 100b.

[0270] Referring to Figure 13, a hot bending machine 2 with non-uniform power distribution of heating tubes is used. The cooling water flow rate of the hot bending machine 2 corresponding to the first crystallization region 100a is greater than the cooling water flow rate corresponding to the second crystallization region 100b.

[0271] Referring to Figure 14, a hot bending machine 2 with non-uniform power distribution of heating tubes is used. The power of the heating tubes in the part of the hot bending machine 2 corresponding to the first crystallization region 100a is less than the power of the heating tubes in the part corresponding to the second crystallization region 100b; and the cooling water flow rate of the hot bending machine 2 corresponding to the first crystallization region 100a is greater than the cooling water flow rate of the part corresponding to the second crystallization region 100b.

[0272] In some embodiments of this application, in order to better obtain a haze gradient effect, the power distribution of the heating tubes of the hot bending machine 2 can be gradient (e.g., gradient increase) from the part corresponding to the first crystallization region 100a to the part corresponding to the second crystallization region 100b, according to the actual haze design requirements; and / or, the cooling water flow rate of the hot bending machine 2 can be gradient (e.g., gradient decrease) from the part corresponding to the first crystallization region 100a to the part corresponding to the second crystallization region 100b.

[0273] After the above-mentioned hot bending treatment, the glass-ceramic can be transformed from a flat sheet into a 3D shape. In the hot bending process, the glass-ceramic can be preheated at 0 to 900°C, then hot-bent at 700°C to 1000°C, and finally cooled to room temperature to obtain a 3D non-uniform crystallized glass-ceramic.

[0274] In the above process, the haze in the region corresponding to the high-temperature thermal field of the microcrystalline glass is greater than the haze in the region corresponding to the low-temperature thermal field. The temperature difference between the high-temperature and low-temperature thermal fields can be designed as needed, for example, it can be ≥30℃. In some embodiments, the temperature difference between the high-temperature and low-temperature thermal fields is about 40℃. In some embodiments, the temperature difference between the high-temperature and low-temperature thermal fields is about 50℃.

[0275] Another embodiment of this application provides a method for preparing the microcrystalline glass 100, including:

[0276] S201. After melting and molding the raw materials of each component of the microcrystalline glass, a glass to be crystallized is obtained; the glass to be crystallized includes a first crystallization region and a second crystallization region;

[0277] S202. After heating and crystallizing the glass to be crystallized, it is then hot-bent to obtain microcrystalline glass 100.

[0278] Among them, heating crystallization is uniform heating crystallization, which means providing the same thermal field to the first region to be crystallized and the second region to be crystallized for heating;

[0279] Hot bending includes at least one non-uniform hot field hot bending, whereby the non-uniform hot field hot bending provides different hot fields to the first and second regions to be crystallized during hot bending.

[0280] The resulting glass-ceramic 100 includes a first region 101 and a second region 102, wherein a first region to be crystallized is used to form the first region 101, and a second region to be crystallized is used to form the second region 102. Both the first region 101 and the second region 102 include a glass phase and a crystalline phase. The first region 101 has a first haze, and the second region 102 has a second haze greater than the first haze. The difference between the first haze and the second haze is greater than or equal to 8%. The first haze and the second haze are measured when the roughness Ra of the two side surfaces of the first region 101 and the second region 102 of the glass-ceramic 100 is ≤100 nm.

[0281] In this embodiment, the microcrystalline glass 100 obtained after step S202 has a 3D form.

[0282] For the specific operation of step S201, please refer to the aforementioned step S101. For the operation of uniform heating crystallization and non-uniform thermal field bending in step S202, please refer to the aforementioned step S102.

[0283] In some embodiments, in step S202, hot bending may further include at least one uniform hot field hot bending, whereby the same hot field is provided to the first and second regions to be crystallized during hot bending. For specific operation, please refer to step S102.

[0284] In some embodiments of this application, hot bending includes a uniform hot bending and a subsequent non-uniform hot bending.

[0285] During the hot bending process, at the junction of the first crystallization region and the second crystallization region, due to the mutual influence of the thermal fields on both sides, a third region connecting the first region and the second region can be formed here. That is, the local region of the first crystallization region adjacent to the second crystallization region and the local region of the second crystallization region adjacent to the first crystallization region together form the third region.

[0286] In the above-mentioned method for preparing microcrystalline glass, steps S102 and S202 may further include chemical strengthening treatment of the non-chemically strengthened microcrystalline glass after obtaining it, namely, ion exchange to form a compressive stress layer, so as to obtain chemically strengthened microcrystalline glass.

[0287] Referring to Figure 15, which is a cross-sectional structural diagram of the microcrystalline glass product 200 provided in an embodiment of this application, the microcrystalline glass product 200 includes a body layer 201, which includes the aforementioned microcrystalline glass 100. The microcrystalline glass product can be of any shape and size, and can be a component applied in various fields and scenarios, such as a cover plate or decorative part for electronic devices. The cover plate for an electronic device can include a display screen cover, a back cover, etc. The decorative part for an electronic device can be a camera decorative part.

[0288] In some embodiments of this application, the microcrystalline glass article 200 further includes an additional layer 202 disposed on the surface of the body layer 201. The additional layer 202 is stacked on the surface of the body layer 201 along the thickness direction of the body layer 201. The additional layer 202 can be provided according to actual functional needs; for example, the additional layer 202 may include an anti-fingerprint layer, and the additional layer 202 may be a single layer or a multi-layer structure.

[0289] Referring to Figure 16, which is a schematic diagram of the structure of the cover plate assembly 300 provided in the embodiment of this application, the cover plate assembly 300 includes a cover plate 301 and a decorative member 302 installed on the cover plate 301. The cover plate 301 includes the aforementioned microcrystalline glass product 200.

[0290] In some embodiments, the cover plate 301 is a back cover for an electronic device, and the decorative element 302 includes a camera decorative element used to decorate the camera 303. The material of the decorative element 302 can be one or more of metal, glass, and microcrystalline glass. In some embodiments, the decorative element 302 includes the aforementioned microcrystalline glass article 200.

[0291] This application also provides a display screen, including a display module and a display screen cover disposed on one side of the display module, the display screen cover including the aforementioned microcrystalline glass product.

[0292] Referring to Figure 17, which is a schematic diagram of the structure of the electronic device 400 provided in this embodiment of the application, the electronic device 400 includes a housing assembly, which includes the microcrystalline glass article 200 described above. The electronic device may be a mobile phone, tablet computer, laptop computer, desktop computer, ultra-mobile personal computer (UMPC), cellular phone, personal digital assistant (PDA), augmented reality (AR) device, virtual reality (VR) device, artificial intelligence (AI) device, wearable device, in-vehicle device, smart home device, and / or smart city device, etc. This embodiment of the application does not impose any special restrictions on the specific type of the electronic device 400.

[0293] In some embodiments, the housing assembly may include a display screen cover (not shown) and a back cover 401 assembled on opposite sides of the electronic device 400, and a camera trim 402 mounted on the back cover 401; wherein one, two, or all three of the display screen cover, the back cover 401, and the camera trim 402 include the aforementioned microcrystalline glass article 200. The camera trim 402 is used to decorate the camera 403.

[0294] The technical solution of this application will be further described below with reference to several embodiments.

[0295] The heat crystallization processes involved in the following embodiments include the following:

[0296] A0: The uniform heating crystallization shown in Figure 7 includes the following heating operations: heating from room temperature to nucleation temperature for 6-10 hours, nucleation at 500℃ to 600℃ for 2-6 hours, crystallization at 600℃ to 800℃ for 1-3 hours, and cooling the crystallization temperature back to room temperature for 4-12 hours or more.

[0297] A0-1: Heating from room temperature to 500℃ for 6-10 hours, nucleation at 500℃ to 600℃ for 2 hours, growth at 680℃ to 800℃ for 1-2 hours, and growth at 800℃ to room temperature for more than 12 hours;

[0298] A0-2: Heating from room temperature to 500℃ for 6-10 hours, nucleation at 500℃ to 600℃ for 2 hours, growth at 600℃ to 640℃ for 1-2 hours, and growth at 800℃ to room temperature for more than 12 hours;

[0299] A0-3: Heating from room temperature to 500℃ for 6-10 hours, nucleation at 500℃ to 600℃ for 2 hours, growth at 640℃ to 680℃ for 1-2 hours, and growth at 800℃ to room temperature for more than 12 hours;

[0300] A1: Non-uniform heating crystallization as shown in Figure 5, the heating operation is the same as A0;

[0301] A2: The non-uniform heating crystallization shown in Figure 5 involves heating from room temperature to 600℃ for 10 min, crystallizing at 600℃ to 900℃ for 10 min to 180 min, and then cooling from 800℃ to room temperature for 1 h to 24 h.

[0302] A2-1: The non-uniform heating crystallization shown in Figure 5 involves heating from room temperature to 600℃ for 10 min, crystallizing at 800℃ to 900℃ for 10 min to 180 min, and then cooling at 800℃ to room temperature for 1 to 24 h.

[0303] A2-2: The non-uniform heating crystallization shown in Figure 5 involves heating from room temperature to 600℃ for 10 min, crystallizing at 600℃ to 700℃ for 10 min to 180 min, and then cooling at 700℃ to room temperature for 1 to 24 h.

[0304] A2-3: The non-uniform heating crystallization shown in Figure 5 involves heating from room temperature to 600℃ for 10 min, crystallizing at 700℃ to 800℃ for 10 min to 180 min, and then at 800℃ to room temperature for 1 h to 24 h.

[0305] A3: Non-uniform heating crystallization as shown in Figure 6, the heating operation is the same as A0;

[0306] A4: The non-uniform heating crystallization shown in Figure 6 is performed using the same heating operation as A2.

[0307] The following embodiments involve several methods for providing a thermal field to the first and second regions to be crystallized during hot bending:

[0308] B0: During hot bending, as shown in Figure 8, the same thermal field is provided to the first and second crystallization areas; in the 3D hot bending process, the area is first preheated at 0 to 900°C, then hot bent at 700°C to 1000°C for 30 to 200 seconds, and finally cooled to room temperature.

[0309] B1: During hot bending, as shown in Figure 9, different thermal fields are provided to the first and second crystallization regions to construct a temperature field difference of ≥30℃.

[0310] B2: During hot bending, as shown in Figure 10, different thermal fields are provided to the first and second crystallization regions to construct a temperature field difference of ≥30℃.

[0311] B3: During hot bending, as shown in Figure 11, different thermal fields are provided to the first and second crystallization regions to construct a temperature field difference of ≥30℃.

[0312] B4: During hot bending, as shown in Figure 12, different thermal fields are provided to the first and second crystallization regions, and the power gradient distribution of the heating tube is used to construct a temperature field difference of about 50°C.

[0313] B5: During hot bending, as shown in Figure 13, different thermal fields are provided to the first and second crystallization regions, and the cooling water flow rate gradient is distributed to create a temperature field difference of about 50°C.

[0314] B6: During hot bending, as shown in Figure 14, different thermal fields are provided to the first and second crystallization regions, with gradient distributions of heating tube power and cooling water flow rate, to create a temperature field difference of approximately 50°C.

[0315] Examples 1 to 9

[0316] The composition of the glass-ceramic and the different heating crystallization processes used are shown in Table 1. The resulting glass-ceramic is a 2D chemically strengthened glass-ceramic with equal thickness in different regions.

[0317] The resulting glass-ceramic includes a first region, a second region, and a third region located between the first and second regions. The haze of the glass-ceramic naturally transitions from the first region through the third region to the second region. The crystal phase, optical characteristics, stress test results, and mechanical property test results of each region are shown in Table 1.

[0318] Comparative Example 1

[0319] The difference from Example 1 is that the heating crystallization process does not use non-uniform heating crystallization.

[0320] Table 1

[0321] Examples 10 to 19

[0322] The composition of the microcrystalline glass was varied, and the same heating crystallization process was used. The specific composition is shown in Table 2. The resulting microcrystalline glass is a 2D chemically strengthened microcrystalline glass with the same thickness in different areas.

[0323] The obtained glass-ceramic includes a first region and a second region. The crystal phase, optical characteristics, stress test results, and mechanical property test results of each region are shown in Table 2.

[0324] Comparative Example 2

[0325] The difference from Example 10 lies in the different formulation of the microcrystalline glass components.

[0326] Comparative Example 3

[0327] The difference from Example 10 lies in the different formulation of the microcrystalline glass components.

[0328] Table 2

[0329] Examples 20 to 29

[0330] The microcrystalline glass components have the same formula, but different heating crystallization processes or different 3D hot bending processes are used, as shown in Table 3. The resulting microcrystalline glass is in 3D form.

[0331] The obtained glass-ceramic includes a first region, a second region, and a third region located between the first and second regions. The haze of the glass-ceramic naturally transitions from the first region through the third region to the second region. The crystal phase, optical characteristics, stress test results, and mechanical property test results of each region are shown in Table 3.

[0332] Comparative Example 4

[0333] The difference from Example 20 is that non-uniform crystallization and non-uniform thermal bending are not performed.

[0334] Table 3

[0335] It should be understood that the use of the terms "first," "second," and various numerical designations in this document is merely for descriptive convenience and is not intended to limit the scope of this application.

[0336] In this application, "and / or" describes the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone, where A and B can be singular or plural. The character " / " generally indicates that the related objects before and after it are in an "or" relationship.

[0337] In this application, "at least one" means one or more, and "more than one" means two or more. "At least one of the following" or similar expressions refer to any combination of these items, including any combination of single or multiple items. For example, "at least one of a, b, or c", or "at least one of a, b, and c" can both mean: a, b, c, a~b (i.e., a and b), a~c, b~c, or a~b~c, where a, b, and c can be single or multiple.

[0338] In this application, “~” represents a range value, including the endpoint values ​​at both ends. For example, the value of a can be 0.5 to 15, meaning that the value of a can be between 0.5 and 15, and includes the endpoint values ​​of 0.5 and 15.

[0339] It should be understood that in the various embodiments of this application, the order of the above processes does not imply the order of execution. Some or all steps may be executed in parallel or sequentially. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of this application.

Claims

1. A microcrystalline glass, characterized in that, The microcrystalline glass includes a first region and a second region, and both the first region and the second region include a glass phase and a crystalline phase; The crystalline phase in the first region includes one or more of lithium silicate phase, lithium disilicate phase and petalite phase, and the crystalline phase in the second region includes one or more of lithium silicate phase, lithium disilicate phase and petalite phase, as well as one or more of quartz phase, quartz solid solution phase and spodumene phase. The first region has a first haze, and the second region has a second haze greater than the first haze. The difference between the first haze and the second haze is greater than or equal to 8%. The first haze and the second haze are measured when the roughness Ra of the two side surfaces of the first region and the second region of the microcrystalline glass is ≤100nm.

2. The microcrystalline glass as described in claim 1, characterized in that, The sum of the mass percentages of the quartz phase, quartz solid solution phase, and spodumene phase in the second region is greater than or equal to 5%.

3. The microcrystalline glass as described in claim 1 or 2, characterized in that, The crystalline phase in the first region does not include the quartz phase, quartz solid solution phase, or spodumene phase.

4. The microcrystalline glass as described in claim 3, characterized in that, The crystalline phases in the first region include lithium disilicate phase and petalite phase; or, The crystalline phases in the first region include lithium silicate phase, lithium disilicate phase, and petalite phase; or, The crystalline phase in the first region includes a lithium silicate phase; or, The crystalline phases in the first region include lithium silicate phase and petalite phase.

5. The microcrystalline glass as described in claim 3 or 4, characterized in that, The crystalline phases in the second region include lithium disilicate, petalite, and quartz; or, The crystalline phases in the second region include lithium disilicate phase, petalite phase, quartz phase, and spodumene phase; or, The crystalline phases in the second region include lithium silicate phase, quartz solid solution phase, and spodumene phase; or, The crystalline phases in the second region include lithium disilicate, petalite, and spodumene; or, The crystalline phases in the second region include lithium disilicate phase, petalite phase, and quartz solid solution phase; or, The crystalline phases in the second region include lithium disilicate phase, lithite phase, quartz solid solution phase, and spodumene phase.

6. The microcrystalline glass as described in claim 1 or 2, characterized in that, The crystalline phase in the first region also includes one or more of the following: quartz phase, quartz solid solution phase, and spodumene phase.

7. The microcrystalline glass as described in claim 6, characterized in that, The crystalline phases in the first region include lithium disilicate phase, petalite phase, and quartz phase; or, The crystalline phases in the first region include lithium silicate phase and quartz solid solution phase; or, The crystalline phases in the first region include lithium disilicate phase and quartz solid solution phase.

8. The microcrystalline glass as described in claim 6 or 7, characterized in that, The crystalline phases in the second region include lithium disilicate, petalite, and quartz; or, The crystalline phases in the second region include lithium disilicate phase, petalite phase, quartz phase, and spodumene phase; or, The crystalline phases in the second region include a quartz solid solution phase and a spodumene phase.

9. The microcrystalline glass according to any one of claims 6-8, characterized in that, The sum of the mass percentages of the quartz phase, quartz solid solution phase, and spodumene phase in the second region is greater than the sum of the mass percentages of the quartz phase, quartz solid solution phase, and spodumene phase in the first region.

10. The microcrystalline glass according to any one of claims 1-9, characterized in that, The total mass percentage of the crystalline phase in the second region is greater than that in the first region.

11. The microcrystalline glass according to any one of claims 1-10, characterized in that, The total mass percentage of the crystalline phase in the first region is greater than or equal to 15%.

12. The microcrystalline glass according to any one of claims 1-11, characterized in that, The average crystal size in the second region is greater than the average crystal size in the first region.

13. The microcrystalline glass according to any one of claims 1-12, characterized in that, The average crystal size in the first region is 10nm to 150nm; the average crystal size in the second region is 50nm to 2000nm.

14. The microcrystalline glass according to any one of claims 1-13, characterized in that, The first haze level is in the range of 0% to 20%; the second haze level is in the range of 8% to 95%.

15. The microcrystalline glass according to any one of claims 1-14, characterized in that, When the microcrystalline glass is 0.3mm to 0.7mm thick, the transmittance is tested in the following mode: the L value of the first region is 40 to 99, the A value is -100 to 100, and the B value is -100 to 100; the L value of the second region is 20 to 95, the A value is -100 to 100, and the B value is -100 to 100.

16. The microcrystalline glass according to any one of claims 1-15, characterized in that, The microcrystalline glass also includes a third region located between the first region and the second region, wherein the haze of the third region gradually increases from the first region to the second region.

17. The microcrystalline glass as described in claim 16, characterized in that, The third region includes a glassy phase and a crystalline phase. The crystalline phase in the third region includes one or more of lithium silicate phase, lithium disilicate phase, and spodumene phase, as well as one or more of quartz phase, quartz solid solution phase, and spodumene phase.

18. The microcrystalline glass as claimed in claim 17, characterized in that, The crystalline phases in the third region include lithium disilicate phase, sulphite phase, and quartz phase; or include lithium silicate phase, lithium disilicate phase, sulphite phase, and quartz phase; or include lithium disilicate phase, sulphite phase, quartz phase, and spodumene phase.

19. The microcrystalline glass according to any one of claims 16-18, characterized in that, The LAB value of the third region is between the LAB value of the first region and the LAB value of the second region, and gradually changes from the first region to the second region.

20. The microcrystalline glass according to any one of claims 1-19, characterized in that, The microcrystalline glass comprises the following components in weight percentages: Li2O: 5%–20%, SiO2: 50%–85%, Al2O3: 4%–15%, P2O5: 0.5%–5%, ZrO2: 2%–10%, TiO2: 0-5%, Na2O: 0-5%, K2O: 0-5%, B2O3: 0-5%, Coloring component: 0-5%.

21. The microcrystalline glass as described in claim 20, characterized in that, The microcrystalline glass satisfies: 4≤(Li2O+SiO2) / Al2O3≤25.

22. The microcrystalline glass as claimed in claim 21, characterized in that, The microcrystalline glass satisfies: 6≤(Li2O+SiO2) / Al2O3≤15.

23. The microcrystalline glass according to any one of claims 20-22, characterized in that, The microcrystalline glass satisfies: 0.5≤Li2O / Al2O3≤5.

24. The microcrystalline glass as described in claim 23, characterized in that, The microcrystalline glass satisfies: 0.9≤Li2O / Al2O3≤2.

5.

25. The microcrystalline glass according to any one of claims 20-24, characterized in that, The microcrystalline glass satisfies: 4≤(SiO2+Al2O3) / (P2O5+TiO2+ZrO2)≤30.

26. The microcrystalline glass as described in claim 25, characterized in that, The microcrystalline glass satisfies: 8≤(SiO2+Al2O3) / (P2O5+TiO2+ZrO2)≤16.

27. The microcrystalline glass according to any one of claims 20-26, characterized in that, The coloring component includes one or more elemental or oxide coloring elements, which include one or more of Au, Ag, Cu, Ni, Co, Fe, Mn, Cr, V, Ti, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu.

28. The microcrystalline glass according to any one of claims 1-27, characterized in that, The microcrystalline glass is either non-chemically strengthened or chemically strengthened; the thickness of the microcrystalline glass is 0.3 mm to 0.7 mm.

29. The microcrystalline glass as described in claim 28, characterized in that, The chemically strengthened glass-ceramic has a tensile stress layer, and the average tensile stress of the chemically strengthened glass-ceramic is greater than 30 MPa; the compressive strength of the chemically strengthened glass-ceramic is greater than 10 kgf.

30. The microcrystalline glass as described in claim 28 or 29, characterized in that, The chemically strengthened microcrystalline glass has a compressive stress layer with a depth greater than 70 μm; the compressive stress CS50 at a depth of 50 μm in the compressive stress layer is ≥40 MPa.

31. A microcrystalline glass, characterized in that, The microcrystalline glass comprises Li2O, SiO2, and Al2O3, and the mass percentage of the three components in the microcrystalline glass satisfies 4 ≤ (Li2O + SiO2) / Al2O3 ≤ 25. The microcrystalline glass includes a first region and a second region, both of which include a glass phase and a crystalline phase. The first region has a first haze, and the second region has a second haze greater than the first haze. The difference between the first haze and the second haze is greater than or equal to 8%. The first haze and the second haze are measured when the surface roughness Ra of both sides of the first region and the second region of the microcrystalline glass is ≤ 100 nm.

32. The microcrystalline glass as described in claim 31, characterized in that, The microcrystalline glass satisfies: 6≤(Li2O+SiO2) / Al2O3≤15.

33. The microcrystalline glass as described in claim 31 or 32, characterized in that, The mass percentages of Li2O and Al2O3 in the microcrystalline glass satisfy 0.5 ≤ Li2O / Al2O3 ≤ 5.

34. The microcrystalline glass as described in claim 33, characterized in that, The microcrystalline glass satisfies: 0.9≤Li2O / Al2O3≤2.

5.

35. The microcrystalline glass according to any one of claims 31-34, characterized in that, The microcrystalline glass comprises the following components in weight percentages: Li2O: 5%–20%, SiO2: 50%–85%, Al2O3: 4%–15%, P2O5: 0.5%–5%, ZrO2: 2%–10%, TiO2: 0-5%, Na2O: 0-5%, K2O: 0-5%, B2O3: 0-5%, Coloring component: 0-5%.

36. The microcrystalline glass as described in claim 35, characterized in that, The microcrystalline glass satisfies: 4≤(SiO2+Al2O3) / (P2O5+TiO2+ZrO2)≤30.

37. The microcrystalline glass as described in claim 36, characterized in that, The microcrystalline glass satisfies: 8≤(SiO2+Al2O3) / (P2O5+TiO2+ZrO2)≤16.

38. The microcrystalline glass according to any one of claims 31-37, characterized in that, The crystalline phase in the first region includes one or more of the following: lithium silicate phase, lithium disilicate phase, lepidolite phase, quartz phase, quartz solid solution phase, and spodumene phase. The crystalline phase in the second region includes at least two of the following: lithium silicate phase, lithium disilicate phase, lepidolite phase, quartz phase, quartz solid solution phase, and spodumene phase.

39. The microcrystalline glass as described in claim 38, characterized in that, The crystalline phase in the first region includes one or more of lithium silicate phase, lithium disilicate phase and petalite phase, and may or may not include one or more of quartz phase, quartz solid solution phase and spodumene phase; the crystalline phase in the second region includes one or more of lithium silicate phase, lithium disilicate phase and petalite phase, and one or more of quartz phase, quartz solid solution phase and spodumene phase.

40. The microcrystalline glass according to any one of claims 31-39, characterized in that, The second region contains more types of crystal phases than the first region; and / or, the total mass percentage of crystal phases in the second region is greater than the total mass percentage of crystal phases in the first region; and / or, the average crystal size in the second region is greater than the average crystal size in the first region.

41. The microcrystalline glass according to any one of claims 31-40, characterized in that, The microcrystalline glass also includes a third region located between the first region and the second region, wherein the haze of the third region gradually increases from the first region to the second region.

42. A method for preparing microcrystalline glass, characterized in that, include: After the raw materials of each component of the microcrystalline glass are melted and molded, the glass to be crystallized is obtained. The glass to be crystallized includes a first crystallization region and a second crystallization region; The glass to be crystallized is heated and crystallized to obtain microcrystalline glass; wherein, the heating and crystallization includes at least one non-uniform heating and crystallization, wherein the non-uniform heating and crystallization is to provide different thermal fields to the first region to be crystallized and the second region to be crystallized for heating respectively; The microcrystalline glass includes a first region and a second region. The first region to be crystallized is used to form the first region, and the second region to be crystallized is used to form the second region. Both the first region and the second region include a glass phase and a crystalline phase dispersed in the glass phase. The first region has a first haze, and the second region has a second haze greater than the first haze. The difference between the first haze and the second haze is greater than or equal to 8%. The first haze and the second haze are measured when the roughness Ra on both sides of the first region and the second region of the microcrystalline glass is ≤100nm.

43. The method for preparing microcrystalline glass according to claim 42, characterized in that, It also includes a hot bending process after the heating and crystallization.

44. The method for preparing microcrystalline glass according to any one of claims 42-43, characterized in that, In the non-uniform heating crystallization process, a heat insulation component is used to shield the first region to be crystallized, while the second region to be crystallized is not shielded, so as to provide different thermal fields for the first region to be crystallized and the second region to be crystallized.

45. A method for preparing microcrystalline glass, characterized in that, include: After the raw materials of each component of the microcrystalline glass are melted and molded, the glass to be crystallized is obtained. The glass to be crystallized includes a first crystallization region and a second crystallization region; The glass to be crystallized is heated and then hot-bent to obtain microcrystalline glass; Wherein, the heating crystallization is uniform heating crystallization, which means heating the first region to be crystallized and the second region to be crystallized by providing the same thermal field; The hot bending includes at least one non-uniform hot field hot bending, wherein the non-uniform hot field hot bending provides different hot fields to the first region to be crystallized and the second region to be crystallized during the hot bending; The microcrystalline glass includes a first region and a second region. The first region to be crystallized is used to form the first region, and the second region to be crystallized is used to form the second region. Both the first region and the second region include a glass phase and a crystalline phase dispersed in the glass phase. The first region has a first haze, and the second region has a second haze greater than the first haze. The difference between the first haze and the second haze is greater than or equal to 8%. The first haze and the second haze are measured when the roughness Ra on both sides of the first region and the second region of the microcrystalline glass is ≤100nm.

46. ​​The method for preparing microcrystalline glass according to claim 45, characterized in that, In the non-uniform heating crystallization process, a heat insulation component is used to shield the first region to be crystallized, while the second region to be crystallized is not shielded, so as to provide different thermal fields for the first region to be crystallized and the second region to be crystallized.

47. The method for preparing microcrystalline glass as described in claim 45 or 46, characterized in that, During the non-uniform thermal bending process, different thermal fields are provided to the first region to be crystallized and the second region to be crystallized, specifically as follows: A hot bending die with non-uniform thermal conductivity is used, wherein the thermal conductivity of the portion of the hot bending die corresponding to the first region to be crystallized is less than the thermal conductivity of the portion corresponding to the second region to be crystallized; and / or, A hot bending machine with non-uniform heating element power distribution is used, wherein the heating element power at the location corresponding to the first crystallization region is less than the heating element power at the location corresponding to the second crystallization region; and / or, A hot bending machine with non-uniform power distribution of heating tubes is used, wherein the cooling water flow rate of the part of the hot bending machine corresponding to the first crystallization area is greater than the cooling water flow rate of the part corresponding to the second crystallization area.

48. The method for preparing microcrystalline glass according to any one of claims 45-47, characterized in that, The hot bending also includes at least one uniform hot bending, wherein the uniform hot bending provides the same hot field to the first region to be crystallized and the second region to be crystallized during the hot bending.

49. A microcrystalline glass product, characterized in that, The microcrystalline glass article includes a body layer, the body layer including the microcrystalline glass according to any one of claims 1-41, or the microcrystalline glass prepared by the method of preparing the microcrystalline glass according to any one of claims 42-44, or the microcrystalline glass prepared by the method of preparing the microcrystalline glass according to any one of claims 45-48.

50. The microcrystalline glass article as described in claim 49, characterized in that, It also includes an additional layer disposed on the surface of the body layer.

51. A cover plate assembly, characterized in that, It includes a cover plate and decorative elements mounted on the cover plate, the cover plate comprising a microcrystalline glass article as claimed in any one of claims 49-50.

52. A display screen, characterized in that, It includes a display module and a display cover plate disposed on one side of the display module, the display cover plate including the microcrystalline glass article as described in any one of claims 49-50.

53. An electronic device, characterized in that, Includes a housing assembly, the housing assembly comprising the microcrystalline glass article of claim 49 or 50.

54. The electronic device as claimed in claim 53, characterized in that, The housing assembly includes a display cover and a back cover assembled on opposite sides of the electronic device; wherein the display cover and / or the back cover includes the microcrystalline glass article.

55. The electronic device as claimed in claim 53, characterized in that, The housing assembly includes a display cover and a rear cover assembled on opposite sides of the electronic device, and a camera trim mounted on the rear cover, wherein the display cover, and / or the rear cover, and / or the camera trim comprises the microcrystalline glass article.

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