CN107840578B

CN107840578B - Glass ceramics and substrate thereof

Info

Publication number: CN107840578B
Application number: CN201711248374.5A
Authority: CN
Inventors: 于天来; 原保平; 聂小兵
Original assignee: CDGM Glass Co Ltd
Current assignee: CDGM Glass Co Ltd
Priority date: 2017-12-01
Filing date: 2017-12-01
Publication date: 2021-06-11
Anticipated expiration: 2037-12-01
Also published as: CN107840578A

Abstract

The invention provides a microcrystalline glass and a substrate thereof,has high thermal conductivity and strength. Microcrystalline glass containing Li₂Si₂O₅The crystal phase and quartz solid solution are main crystal phases, and the total content thereof in the microcrystalline glass accounts for less than 50% but 35% or more by weight of the microcrystalline glass. The microcrystalline glass has a thermal conductivity of 2 w/m.k or more at room temperature, and a Vickers hardness of 600kgf/mm after tempering²The above. The microcrystalline glass or the substrate is suitable for protective components of portable electronic equipment, optical equipment and the like, particularly used as a rear cover plate, has high heat conductivity and strength, and is transparent or can have different individual colors. The crystallized glass of the present invention has high thermal conductivity, and therefore can be used as a heat conductive material, and can be used for other decorations such as an outer frame member of a portable electronic device having a specific outer shape of a glass material.

Description

Glass ceramics and substrate thereof

Technical Field

The present invention relates to a glass ceramic and a substrate using the glass ceramic as a base material, and more particularly, to a glass ceramic and a substrate having high thermal conductivity and high strength, which are suitable for a protective member such as a portable electronic device or an optical device.

Background

For portable electronic devices such as smart phones, tablet PCs, and other optical devices, a back cover is used to protect the internal electronics. These protective materials for the back cover, particularly for electronic devices that require wireless signals, are required to have high thermal conductivity, different individual colors, and high strength, to be able to be used in harsh environments, and to have good processability. In the past, metal is generally used as a rear cover protection material, but the metal rear cover can seriously affect the signal acceptance, only can be designed into a sectional type, and the metal rear cover cannot be used along with the development of a 5G signal.

As a ceramic material which does not affect signals, the ceramic material has good texture and higher thermal conductivity, but has poorer processability and higher cost compared with glass. At present, the common glass has low thermal conductivity and low strength, and the use of the common glass as a rear cover material of electronic equipment is limited.

Glass ceramics are also called glass ceramics, and are materials in which crystals are precipitated inside glass by heat treatment of glass. The crystallized glass can have physical properties that cannot be obtained in glass due to crystals dispersed therein. For example, the mechanical strength such as Young's modulus and fracture toughness, the etching characteristics with an acidic or alkaline chemical solution, the thermal properties such as the thermal expansion coefficient, and the increase and decrease of the glass transition temperature. The microcrystalline glass has higher mechanical properties, and the heat conductivity of the glass can be improved because the microcrystalline glass is formed in the glass, but the conventional microcrystalline glass is not suitable for the protective material because the heat conductivity and the strength are poor. In addition, conventional glass ceramics have low productivity because of high viscosity and high devitrification of the base glass, and thus are difficult to be used for the protective material.

Japanese patent application laid-open No. 2014-114200 discloses a crystallized glass substrate for an information recording medium, which cannot obtain a sufficient compressive stress value after chemical tempering and cannot form a deep stress layer.

Disclosure of Invention

The invention aims to provide microcrystalline glass and a substrate thereof, which have higher thermal conductivity and strength.

The technical scheme adopted by the invention for solving the technical problem is as follows: microcrystalline glass containing Li₂Si₂O₅The crystal phase and quartz solid solution are main crystal phases, and the total content thereof in the microcrystalline glass accounts for less than 50% but 35% or more by weight of the microcrystalline glass.

Further, the components of the composition by weight percent are as follows: SiO 2₂ 60～80％；Al₂O₃ 4～20％；Li₂O 0～15％；Na₂O is greater than 0 but less than or equal to 12%; k₂O 0～5％；ZrO₂Greater than 0 but less than or equal to 5%; p₂O₅ 0～5％；TiO₂ 0～6％。

Further, the method also comprises the following steps: b is₂O₃0 to 5 percent; and/or MgO 0-2%; and/or 0-2% of ZnO; and/or 0-5% of CaO; and/or 0-5% of BaO; and/or 0-3% of FeO; and/or SnO₂0-2%; and/or 0-5% of SrO; and/or La₂O₃0 to 10 percent; and/or Y₂O₃0 to 10 percent; and/or Nb₂O₅0 to 10 percent; and/or Ta₂O₅0 to 10 percent; and/or WO₃ 0～5％。

The microcrystalline glass comprises the following components in percentage by weight: SiO 2₂ 60～80％；Al₂O₃ 4～20％；Li₂O0～15％；Na₂O is greater than 0 but less than or equal to 12%; ZrO (ZrO)₂Greater than 0 but less than or equal to 5%; p₂O₅ 0～5％；TiO₂ 0～6％；B₂O₃0～5％；K₂O 0～5％；MgO 0～2％；ZnO 0～2％；CaO 0～5％；BaO 0～5％；FeO 0～3％；SnO₂ 0～2％；SrO 0～5％；La₂O₃ 0～10％；Y₂O₃ 0～10％；Nb₂O₅ 0～10％；Ta₂O₅ 0～10％；WO₃0 to 5 percent; 0-5% of a clarifying agent and containing Li₂Si₂O₅The crystal phase and quartz solid solution are main crystal phases, and the total content of the crystal phase and the quartz solid solution in the microcrystalline glass accounts for no more than 50% of the weight of the microcrystalline glass.

Further, SiO₂65-78%; and/or Al₂O₃5-18%; and/or Li₂0-12% of O; and/or Na₂0.5-10% of O; and/or ZrO₂0.4-3%; and/or P₂O₅0.4-3%; and/or TiO₂0.5-5%; and/or B₂O₃0 to 4 percent; and/or K₂0.5-4% of O; and/or MgO is greater than 0 but less than or equal to 2%; and/or ZnO is greater than 0 but less than or equal to 2%; and/or 0-4% of CaO; and/or 0-4% of BaO; and/or 0-1% of FeO; and/or SnO₂0.01-1%; and/or 0-3% of SrO; and/or La₂O₃0 to 9 percent; and/or Y₂O₃0 to 9 percent; and/or Nb₂O₅0-8%; and/or Ta₂O₅0-8%; and/or WO₃0-2%; and/or the fining agent comprises As₂O₃、Sb₂O₃、CeO₂And 0 to 5% of one or more selected from the group consisting of F, Cl, NOx and SOx.

Further, SiO₂/Li₂O is 4-10; and/or ZrO₂/Li₂O is 0 to 0.5; and/or Al₂O₃/(Na₂O+Li₂O) is 0.5 to 2; and/or Li₂O/Na₂O is 0.8 to 8; and/or ZrO₂+P₂O₅+TiO₂0.5 to 10%.

Further, SiO₂68-75%; and/or Al₂O₃6-15%; and/or Li₂6-10% of O; and/or Na₂O2-8%; and/or ZrO₂0.8-2%; and/or P₂O₅0.8-2%; and/or TiO₂1-4%; and/or B₂O₃0 to less than 2 percent; and/or K₂0.8-3% of O; and/or 0-3% of CaO; and/or BaO 0-3%; and/or SnO₂0.05-0.4%; and/or 0-1% of SrO; and/or La₂O₃Greater than 0 but less than or equal to 8%; and/or Y₂O₃Greater than 0 but less than or equal to 8%; and/or Nb₂O₅0 to 5 percent; and/or Ta₂O₅0 to 5 percent; and/or WO₃0 to 1 percent; and/or 0-2% of a clarifying agent.

Further, SiO₂/Li₂O is 4.5 to 9.5; and/or ZrO₂/Li₂O is greater than 0 but less than 0.35; and/or Al₂O₃/(Na₂O+Li₂O) is 0.7 to 1.8; and/or Li₂O/Na₂O is 1.5 to 7.5; and/or ZrO₂+P₂O₅+TiO₂1 to 8 percent.

Further, Na₂O4-8%, preferably more than 5% but less than or equal to 8%; and/or Al₂O₃7-15%; and/or ZrO₂1-2%; and/or P₂O₅1-2%; and/or TiO₂1.5-4%; and/or K₂1-3% of O; and/or 0-1% of CaO; and/or 0-1% of BaO; and/or SnO₂0.05-0.2%; and/or 0-1% of a clarifying agent; and/or SiO₂/Li₂O is 5-9; and/or ZrO₂/Li₂O is greater than 0 but less than or equal to 0.30; and/or Al₂O₃/(Na₂O+Li₂O) is 1 to 1.5; and/or Li₂O/Na₂O is 2 to 7, preferably Li₂O/Na₂O is 2-6; and/or ZrO₂+P₂O₅+TiO₂2 to 6 percent.

Further, NiO and/or Ni is contained₂O₃The total amount is not more than 6%, preferably not more than 4%, more preferably not more than 3%, and the lower limit of the total amount is not less than 0.1%; or contains Pr₂O₅The content is not more than 8%, preferably not more than 6%, more preferably not more than 5%, and the lower limit of the content is more than 0.4%; or containing CoO and/or Co₂O₃The total amount is not more than 2%, preferably not more than 1.8%, and the lower limit of the total amount is not less than 0.05%; or containing Cu₂O and/or CeO₂The total amount is not more than 4%, preferably not more than 3%, and the lower limit of the total amount is not less than 0.5%; or containing Fe₂O₃The content is not more than 8%, preferably not more than 5%, more preferably not more than 3%; or containing Fe₂O₃And CoO, CoO not exceeding 0.3%; or containing Fe₂O₃And Co₂O₃，Co₂O₃Not more than 0.3%; or containing Fe₂O₃CoO and NiO; or containing Fe₂O₃、Co₂O₃And NiO; or containing Fe₂O₃CoO and Co₂O₃Wherein, CoO and Co₂O₃The lower limit of the total amount is more than 0.2 percent; or containing Fe₂O₃CoO, NiO and Co₂O₃(ii) a Or containing MnO₂The content is not more than 4 percent, preferably within 3 percent, and the lower limit of the content is more than 0.1 percent; or containing Er₂O₃The content is not more than 8 percent, preferably within 6 percent, and the lower limit of the content is more than 0.4 percent; or containing Nd₂O₃The content is not more than 8 percent, preferably within 6 percent, and the lower limit of the content is more than 0.4 percent; or containing Er₂O₃、Nd₂O₃And MnO₂，Er₂O₃Content within 6% of Nd₂O₃Content within 4%, MnO₂The content is within 2 percent, and the lower limit of the total amount is more than 0.9 percent; or containing Cr₂O₃The content is not more than 4%, preferably not more than 3%, more preferably not more than 2%The lower limit of the content is more than 0.2 percent; or contain V₂O₅The content is not more than 4%, preferably not more than 3%, more preferably not more than 2%, and the lower limit of the content is not less than 0.2%.

Further, Li₂Si₂O₅The content of the crystal phase in the microcrystalline glass is 20% or more but less than 35% by weight, more preferably 20 to 30% by weight, and still more preferably 20 to 25% by weight.

Further, the weight% of the crystal phase of quartz and quartz solid solution in the microcrystalline glass is 15% or more and less than 30%, preferably 20 to 29%, and more preferably 25 to 29%.

Further, the Li₂Si₂O₅The total content of the crystal phase and the quartz and quartz solid solution in the glass ceramics is 48% or less, preferably 46% or less, by weight of the glass ceramics.

Further, LiAlSi₄O₁₀The crystal phase accounts for no more than 15 percent of the weight of the microcrystalline glass.

Further, the upper limit of the glass liquidus temperature is 1450 ℃, preferably 1400 ℃, more preferably 1380 ℃, and most preferably 1320 ℃.

Further, the glass has a thermal conductivity of 2 w/m.k or more at room temperature (25 ℃ C.).

The microcrystalline glass substrate is prepared by chemically toughening the microcrystalline glass.

Further, the Vickers hardness (Hv) is 600kgf/mm²Above, preferably 650kgf/mm²Above, more preferably 700kgf/mm²The above.

Further, the 32g steel ball is dropped from a height of 500mm toward the glass-ceramic substrate without breaking, and the height is preferably 650mm or more, more preferably 800mm or more.

Further, the three-point bending strength is 450MPa or more, preferably 600MPa or more, and more preferably 800MPa or more.

Further, a compressive stress layer having a compressive stress value of 300Mpa or more, preferably 400Mpa or more, and more preferably 500Mpa or more is formed by ion exchange treatment.

Further, the thickness of the compressive stress layer is 1 μm or more, preferably 5 μm or more, and more preferably 8 μm or more.

The invention has the beneficial effects that: the microcrystalline glass of the present invention has a thermal conductivity of 2 w/m.k or more at room temperature and a Vickers hardness (Hv) of 600kgf/mm after tempering²The above. The microcrystalline glass or the substrate is suitable for protective components of portable electronic equipment, optical equipment and the like, particularly used as a rear cover plate, has high heat conductivity and strength, and is transparent or can have different individual colors. The crystallized glass of the present invention has high thermal conductivity, and therefore can be used as a heat conductive material, and can be used for other decorations such as an outer frame member of a portable electronic device having a specific outer shape of a glass material.

Detailed Description

The crystallized glass of the present invention is a material having a crystal phase and a glass phase, which is different from an amorphous solid. The crystal phase of the crystallized glass can be discriminated by the angle of the peak appearing in the X-ray diffraction pattern of the X-ray diffraction analysis, and by TEMEDX. The crystallized glass of the present invention contains R in the crystal phase₂SiO₃、R₂Si₂O₅、R₂TiO₃、R₄Ti₅O₁₂、R₃PO₃、RAlSi₂O₆、RAlSiO₄O₁₀、R₂Al₂Si₂O₈、R₄Al₄Si₅O₁₈And quartz solid solution, wherein R is more than 1 of Li, Na and K.

The invention controls the crystallization process and the content of the components, and Li₂Si₂O₅The crystal phase and quartz solid solution are main crystal phases, and the total content of the crystal phase and the quartz solid solution accounts for less than 50 percent of the weight of the glass ceramics in the glass ceramics, and researches show that if the content of the main crystal phase exceeds 50 percent, the crystal phase content is higher in the glass, so that the glass ceramics have poor toughening effect, cannot play a role in increasing the strength of the glass, but can reduce the strength of the glass, preferably, Li₂Si₂O₅The total content of the crystal phase and quartz solid solution is 48% or less, more preferably 46% or less; the lower limit of the total content is 35%.

Li as above₂Si₂O₅The crystal phase is a lithium disilicate crystal phase and is based on [ Si ]₂O₅]The crystal is flat or platy, the lithium disilicate crystal phase is a random non-oriented interlocking microstructure inside the microcrystalline glass, a path is bent when a crack passes through the crystal, so that the crack is prevented from expanding, the strength and the toughness of the microcrystalline glass are improved, and compared with the glass phase, the lithium disilicate crystal phase has high thermal conductivity, so that the thermal conductivity of the microcrystalline glass is improved. In the microcrystalline glass of the present invention, Li₂Si₂O₅The content of the crystal phase in the microcrystalline glass is preferably 20% or more and less than 35%, more preferably 20 to 30%, and still more preferably 20 to 25% by weight.

The crystal phase of the quartz and the quartz solid solution belongs to a trigonal or hexagonal system, exists in the microcrystalline glass in a spherical form, can further prevent the expansion of microcracks, and improves the bending strength and toughness of the microcrystalline glass. The weight percent of the crystal phase of quartz and quartz solid solution in the microcrystalline glass is preferably greater than or equal to 15% but less than 30%, preferably 20-29%, and more preferably 25-29%.

Petalite LiAlSi₄O₁₀Is a monoclinic crystal with folded Si connected by Li and Al tetrahedra₂O₆The three-dimensional framework structure of the layered structure of the layers has a low coefficient of expansion, can be used for improving the thermal shock resistance of the glass-ceramic, and is an auxiliary crystalline phase of the glass-ceramic, wherein the auxiliary crystalline phase accounts for not more than 15% of the weight of the glass-ceramic in the glass-ceramic.

The inventors of the present invention have made extensive experiments and studies, and have obtained a glass ceramic or a glass ceramic substrate of the present invention at a low cost by specifying the content and content ratio of specific components constituting the glass ceramic to specific values and precipitating specific crystal phases. The compositional ranges of the respective components of the glass ceramics of the present invention will be explained below. In the present specification, the contents of the respective components are all expressed in wt% with respect to the total amount of glass matter converted into the composition of oxides, if not specifically stated. Here, the "composition in terms of oxide" means that when all of the oxides, complex salts, metal fluorides, and the like used as the raw materials of the glass-ceramic composition component of the present invention are decomposed and converted into oxides at the time of melting, the total amount of the oxides is 100%. In the present specification, the term "glass" may include raw glass before crystallization.

SiO₂Is an essential component for forming the glass network structure of the glass ceramics of the present invention, and is also an essential component which can be a constituent crystal phase by heat treatment of the original glass. If the amount is less than 60%, the resulting glass is inferior in chemical durability and resistance to devitrification. Thus, SiO₂The lower limit of the content is preferably 60%, more preferably 65%, and still more preferably 68%. On the other hand, by using SiO₂The content of (b) is 80% or less, and excessive increase in viscosity and decrease in meltability can be suppressed. Thus, SiO₂The upper limit of the content is preferably 80%, more preferably 78%, and still more preferably 75%.

Al₂O₃With SiO₂Also, a component forming a network structure of glass, which is an important component contributing to stabilization of raw glass and improvement of chemical durability, may further improve the thermal conductivity of glass, but if the content thereof is less than 4%, the effect is not good. Thus, Al₂O₃The lower limit of the content is 4%, preferably 5%, more preferably 6%, and still more preferably 7%. On the other hand, if Al₂O₃When the content of (b) exceeds 20%, the meltability and devitrification resistance are lowered. Thus, Al₂O₃The upper limit of the content is 20%, preferably 18%, more preferably 15%.

Li₂O is an optional component for improving the low-temperature melting property and the formability of the glass, and can be an essential component for forming a desired crystal phase by heat treatment of the raw glass. But if the content is less than 6 percentThe effect is not good. On the other hand, if Li is contained excessively₂O, a decrease in chemical durability or an increase in the average linear expansion coefficient is likely to occur. Thus, Li₂The upper limit of the O content is preferably 15%, more preferably 12%, and still more preferably 10%. When chemical tempering is performed by ion exchange, if Li is contained in the microcrystalline glass₂The O component is very effective in forming a deep compressive stress layer.

Na₂O is an optional component for improving low-temperature melting property and moldability, and Na is excessively contained₂O is liable to cause a decrease in chemical durability or an increase in the average linear expansion coefficient, and therefore, Na₂The upper limit of the O content is preferably 12%, more preferably 10%, most preferably 8%. When chemically tempered by ion exchange, the microcrystalline glass contains Na₂O component, Na in the glass ceramics⁺Ion and K⁺Ion exchange is very effective in forming the compressive stress layer. Thus, in chemical tempering by ion exchange, Na₂The lower limit of the O content is more than 0, preferably 0.5%, more preferably 2%, still more preferably 4%, and most preferably more than 5%.

P₂O₅The ability to phase separate in the glass to form nuclei is an optional component that contributes to the improvement in the low-temperature melting properties of the glass. P₂O₅The lower limit of the content is preferably more than 0, more preferably 0.4%, further preferably 0.8%, most preferably 1%, but if P is contained excessively₂O₅The deterioration of devitrification resistance and phase separation of the glass are easily caused. Thus, P₂O₅The upper limit of the content is preferably 5%, more preferably 3%, and most preferably 2%.

ZrO₂Has the function of crystallization precipitation to form crystal nucleus, and is also an optional component which contributes to the improvement of the chemical durability of the glass. ZrO (ZrO)₂The lower limit of the content is preferably more than 0, more preferably 0.4%, further preferably 0.8%, most preferably 1%, but if ZrO is contained excessively₂The resistance to devitrification of the glass is easily lowered. Thus, ZrO₂The upper limit of the content is preferably 5%, more preferably 3%, and most preferably 5%2％。

TiO₂Is an optional component which is helpful for reducing the melting temperature of the microcrystalline glass and improving the chemical durability. TiO 2₂The lower limit of the content is preferably more than 0, more preferably 0.5%, further preferably 1%, most preferably 1.5%. On the other hand, by making TiO₂The content of (A) is 6% or less, and the melting temperature of the glass ceramics can be lowered. Thus, TiO₂The upper limit of the content is preferably 6%, more preferably 5%, most preferably 4%.

In the present invention, in order to obtain a desired crystal phase and thereby improve the thermal conductivity and hardness of the glass-ceramic substrate, it is necessary to control SiO₂Relative to Li₂Ratio of O content, i.e. making SiO₂/Li₂The value of O is 4 to 10. In order to more easily obtain the effect, SiO₂/Li₂The lower limit of the value of O is preferably 4, more preferably 4.5, most preferably 5; SiO 2₂/Li₂The upper limit of the value of O is preferably 10, more preferably 9.5, most preferably 9.

In the present invention, in order to obtain uniform fine and more crystal phases in the glass and thereby improve the thermal conductivity and bending strength of the glass-ceramic substrate, it is necessary to control ZrO₂Relative to Li₂Ratio of O content, i.e. to ZrO₂/Li₂The value of O is 0 to 0.5, preferably greater than 0 but less than 0.35, more preferably greater than 0 but less than or equal to 0.30.

In the present invention, in order to obtain a good tempering effect and thereby improve the strength of the glass-ceramic substrate, it is necessary to control Al₂O₃Relative to LiO₂And Na₂Ratio of total O content, i.e. Al₂O₃/(Na₂O+Li₂O) is preferably 0.5, more preferably 0.7, most preferably 1; al (Al)₂O₃/(Na₂O+Li₂O) is preferably 2, more preferably 1.8, most preferably 1.5.

In the present invention, in order to improve the devitrification resistance and the meltability and formability during melting, it is necessary to control Li₂O relative to Na₂The ratio of O, i.e. such thatLi₂O/Na₂The value of O is preferably 0.8 to 8. In order to more easily obtain the effect, Li₂O/Na₂The lower limit of the value of O is preferably 0.8, more preferably 1.5, most preferably 2; li₂O/Na₂The upper limit of the value of O is preferably 8, more preferably 7.5, still more preferably 7, and most preferably 6.

In the present invention, ZrO is controlled so that uniform crystals can be precipitated₂、P₂O₅And TiO₂I.e. ZrO₂+P₂O₅+TiO₂0.5 to 10%. In order to more easily obtain the effect, ZrO₂+P₂O₅+TiO₂The lower limit of the value of (b) is preferably 0.5%, more preferably 1%, and further preferably 2%; ZrO (ZrO)₂+P₂O₅+TiO₂The upper limit of the value of (b) is preferably 10%, more preferably 8%, and still more preferably 6%.

B₂O₃The glass is beneficial to reducing the viscosity of the glass, improving the melting property and the formability of the glass and improving the toughening property of the glass, so the glass can be added as an optional component. If B is contained excessively₂O₃The chemical durability of the glass ceramics is likely to be lowered, and the precipitation of desired crystals is likely to be suppressed. Thus, B₂O₃The upper limit of the content is preferably 5%, more preferably 4%, most preferably less than 2%.

K₂O is an optional component for improving the low-temperature melting property and the formability of the glass, but if K is excessively contained, K is excessively contained₂O, a decrease in chemical durability and an increase in the average linear expansion coefficient are easily generated. Thus, K₂The upper limit of the O content is preferably 5%, more preferably 4%, most preferably 3%. When chemical tempering is performed by ion exchange, if K is contained in the glass ceramics₂O is very effective in forming a deep compressive stress layer. Thus, when chemically tempered by ion exchange, K₂The lower limit of the O content is preferably more than 0, more preferably 0.5%, further preferably 0.8%, and most preferably 1%.

MgO is an optional component contributing to lowering the viscosity of glass and suppressing devitrification of raw glass during molding, and also has an effect of improving low-temperature meltability, and the lower limit of the MgO content is preferably more than 0; however, if the content of MgO is too high, devitrification resistance may be deteriorated, and undesirable crystals are obtained after crystallization, resulting in deterioration of the performance of the glass ceramics, so that the upper limit of the content of MgO is preferably 2%.

ZnO can improve the melting performance of the glass and improve the chemical stability of the glass, and is an optional component, and the lower limit of the ZnO content is preferably more than 0; on the other hand, the upper limit of the ZnO content is controlled to 2% or less, and the deterioration of the devitrification property can be suppressed.

CaO is an optional component contributing to improvement of the low-temperature melting property of the glass, but if CaO is contained excessively, resistance to devitrification is liable to be lowered. Therefore, the upper limit of the CaO content is preferably 5%, more preferably 4%, further preferably 3%, and most preferably 1%.

BaO is an optional component contributing to improvement of the low-temperature melting property of the glass, but if BaO is excessively contained, resistance to devitrification is easily lowered. Therefore, the upper limit of the BaO content is preferably 5%, more preferably 4%, further preferably 3%, and most preferably 1%.

FeO can be contained arbitrarily because it functions as a refining agent, but if FeO is contained excessively, excessive coloring or alloying of platinum in the glass melting apparatus tends to occur. Therefore, the upper limit of the FeO content is preferably 3%, more preferably 1%.

SnO₂Is an optional component capable of exerting the function as a clarifying agent and the function of precipitating crystals to form crystal nuclei. Thus, SnO₂The lower limit of the content is preferably more than 0, more preferably 0.01%, most preferably 0.05%; however, if it contains too much SnO₂The resistance to devitrification of the glass is easily lowered. Thus, SnO₂The upper limit of the content is preferably 2%, more preferably 1%, still more preferably 0.4%, most preferably 0.2%.

SrO is an optional component for improving the low-temperature melting property of the glass, but if SrO is contained excessively, resistance to devitrification is liable to be lowered. Therefore, the upper limit of the SrO content is preferably 5%, more preferably 3%, and most preferably 1%.

La₂O₃Is an optional component for improving the hardness of the microcrystalline glass, can reduce the melting temperature of the glass by adding a small amount, and can reduce the liquid phase temperature to a certain extent, but if La is excessively contained, the hardness of the microcrystalline glass is improved₂O₃The resistance to devitrification is liable to be lowered. Thus, La₂O₃The content range of (B) is 10% or less, preferably 9% or less, more preferably greater than 0 but 8% or less.

Y₂O₃Is an optional component for improving the hardness, chemical stability and thermal conductivity of the glass-ceramic, and can reduce the melting temperature of the glass and the liquidus temperature to some extent by adding a small amount, but if Y is contained excessively₂O₃The resistance to devitrification is liable to be lowered. Thus, Y₂O₃The content of (B) is 10% or less, preferably 9% or less, more preferably greater than 0 but 8% or less.

Nb₂O₅Is an optional component for improving the mechanical strength of the glass ceramics, but if Nb is contained excessively₂O₅The resistance to devitrification is liable to be lowered. Thus, Nb₂O₅The upper limit of the content is preferably 10%, more preferably 8%, most preferably 5%.

Ta₂O₅Is an optional component for improving the mechanical strength of the glass, but if Ta is contained excessively₂O₅The resistance to devitrification is liable to be lowered. Thus, Ta₂O₅The upper limit of the content is preferably 10%, more preferably 8%, most preferably 5%.

WO₃Is an optional component for improving the mechanical strength of the glass, but if too much WO is contained₃The resistance to devitrification is liable to be lowered. Thus, WO₃The upper limit of the content is preferably 5%, more preferably 2%, most preferably 1%.

As may be contained As a fining agent in the glass ceramics of the present invention₂O₃、Sb₂O₃、CeO₂And one or more selected from the group consisting of F, Cl, NOx, and SOx. However, the upper limit of the content of the clarifying agent is preferably 5%, more preferably 2%, most preferably 1％。

The microcrystalline glass of the invention can be added with a certain coloring agent to prepare microcrystalline glass with different colors.

Using NiO and/or Ni₂O₃For colorants for the preparation of brown or green glass ceramics, the two components can be used individually or in combination, in amounts of generally not more than 6%, preferably not more than 4%, more preferably not more than 3%, respectively, with the lower limit of the respective amounts being above 0.1%, if NiO and Ni are present₂O₃When mixed, NiO and Ni₂O₃The total amount of (A) is generally not more than 6%, and if the content exceeds 6%, the colorant is not well dissolved in the glass.

Using Pr₂O₅As a colorant for green glass compositions, it is used alone, and is generally contained in an amount of not more than 8%, preferably not more than 6%, more preferably not more than 5%, with the lower limit thereof being 0.4% or more, and if the content is less than 0.4%, the color of the glass is not conspicuous.

Using CoO and/or Co₂O₃For the colorant, for the preparation of blue glass ceramics, the two colorant components may be used alone or in admixture, and both of them are generally contained in an amount of not more than 2%, preferably not more than 1.8%, respectively, and if the content exceeds 2%, the colorant is not well soluble in the glass, such as CoO and Co when used in admixture₂O₃The total amount is not more than 2%, and the respective contents thereof are limited to 0.05% or more, for example, less than 0.05%, and the color of the glass is not conspicuous.

Using Cu₂O and/or CeO₂For the colorant, a yellow glass-ceramic is prepared, the two colorant components being used individually or in a mixture, Cu being used alone₂O, the content is not more than 4%, preferably not more than 3%, and if the content exceeds 4%, the glass is easily crystallized; using CeO alone₂The content is usually not more than 4%, preferably not more than 3%, for example, the content exceeds 4%, and the glass is poor in gloss. When two kinds of colorants are used in combination, the total amount thereof is usually not more than 4% and the lower limit of the content is 0.5% or more.

Use of Fe alone₂O₃Is a colorant; or using Fe₂O₃And CoO; or using Fe₂O₃And Co₂O₃Two colorants used in combination; or using Fe₂O₃Three colorants mixed together, CoO and NiO; or using Fe₂O₃、Co₂O₃And NiO; or using Fe₂O₃CoO and Co₂O₃Three colorants used in combination; or using Fe₂O₃CoO, NiO and Co₂O₃Four colorants were used in combination to produce black and grayish-black glass ceramics. Use of Fe alone₂O₃Coloring, in an amount not exceeding 8%, preferably not exceeding 5%, more preferably not exceeding 3%. CoO and Co₂O₃Can increase the blackness of the glass by absorbing visible light, and is generally matched with Fe₂O₃When used in admixture, CoO with Co₂O₃Respectively not more than 0.3%, CoO and Co₂O₃The lower limit of the total amount is more than 0.2 percent. NiO absorbs visible light and can deepen the blackness of the glass, and the content of NiO does not exceed 1 percent when the NiO is mixed for use.

Using MnO₂The content of the purple microcrystalline glass prepared by the method as a coloring agent is generally not more than 4 percent, preferably within 3 percent, and the lower limit of the content is more than 0.1 percent, such as the content is less than 0.1 percent, and the color of the glass is not obvious.

Use of Er₂O₃Is a colorant used for preparing pink microcrystalline glass, and the content of the colorant is generally not more than 8%, and preferably within 6%. Because of rare earth element Er₂O₃The coloring efficiency is low, when the content exceeds 8 percent, the color of the glass cannot be further deepened, but the cost of the glass is increased, and the lower limit of the content is more than 0.4 percent, such as less than 0.4 percent, and the color of the glass is not obvious.

Using Nd₂O₃For the colouring agent, a mauve glass composition is prepared, generally in a quantity not exceeding 8%, preferably within 6%. Due to rare earth element Nd₂O₃The coloring efficiency is low, the use content is more than 8 percent, and the color of the glass cannot be improvedThe cost of the glass is increased instead by deepening one step, the lower limit of the content of the glass is more than 0.4 percent, such as less than 0.4 percent, and the color of the glass is not obvious.

Use of Er₂O₃、Nd₂O₃And MnO₂Mixing the colorants to prepare the red glass-ceramic glass, wherein Er ions in the glass have absorption at 400-500nm, Mn ions mainly have absorption at 500nm, Nd ions mainly have strong absorption at 580nm, and the red glass composition can be prepared by mixing the Er ions and the Mn ions₂O₃And Nd₂O₃Coloring rare earth, relatively weak coloring ability, Er₂O₃The usage amount is less than 6 percent, Nd₂O₃The usage amount is less than 4 percent, the coloring of Mn ions is strong, and MnO is added₂The amount of the colorant is within 2%, and the lower limit of the total amount of the colorant mixture is 0.9% or more.

Using Cr₂O₃As a colorant for green glass compositions, it is used alone, and is generally contained in an amount of not more than 4%, preferably not more than 3%, more preferably not more than 2%, with the lower limit being not less than 0.2%, and if the content is less than 0.2%, the color of the glass is not conspicuous.

Using V₂O₅As a colorant for a yellow-green glass composition, it is used alone, and is generally contained in an amount of not more than 4%, preferably not more than 3%, more preferably not more than 2%, with the lower limit thereof being 0.2% or more, e.g., less than 0.2%, the color of the glass is not conspicuous.

In the glass ceramics of the present invention, the glass composition may be composed of only the above components, but other components may be added within a range not seriously impairing the glass characteristics. For example, TeO may be added₂、Bi₂O₃、GeO₂And the like.

The crystallized glass of the present invention has the following characteristics.

The devitrified glass of the present invention has high devitrification resistance, and more specifically, has a low liquidus temperature. That is, the upper limit of the glass liquidus temperature in the present invention is preferably 1450 ℃, more preferably 1400 ℃, still more preferably 1380 ℃, and most preferably 1320 ℃. This can reduce devitrification when forming glass from a molten state even if the molten glass is discharged at a relatively low temperature. Further, since the glass can be molded even if the melting temperature of the glass is lowered, the deterioration of the platinum device and the mold can be suppressed, and the energy consumption at the time of molding the glass can be reduced, thereby reducing the production cost of the glass.

On the other hand, the lower limit of the liquidus temperature of the glass of the present invention is not particularly limited, and the lower limit of the liquidus temperature of the glass produced by the present invention is preferably 1000 ℃, more preferably 1100 ℃, and most preferably 1200 ℃.

The liquidus temperature is an index of resistance to devitrification, and in the present specification, a value measured by the following method is used as the liquidus temperature. First, a 30cc glass cullet-like glass sample was placed in a platinum crucible having a capacity of 50ml, and held at 1500 ℃ in a completely molten state; then, after cooling to a predetermined temperature and holding for 12 hours, the glass was taken out of the furnace and cooled, and the presence or absence of crystals in the glass surface and the glass was observed, and the temperature was observed up to 1200 ℃ in units of 10 ℃ and the lowest temperature at which crystals were not observed was taken as the liquidus temperature.

The microcrystalline glass of the present invention has a thermal conductivity of 2W/m.k or more.

The microcrystalline glass substrate can form a compressive stress layer through ion exchange treatment and implement chemical toughening. When the compressive stress layer is formed, the value of the compressive stress layer is preferably 300MPa or more. With such a compressive stress value, it is possible to suppress the extension of cracks and improve the mechanical strength. Therefore, when chemical tempering is performed, the value of the compressive stress layer of the crystallized glass substrate of the present invention is preferably 300Mpa or more, more preferably 400Mpa or more, and most preferably 500Mpa or more.

The thickness of the compressive stress layer of the glass-ceramic substrate of the present invention is preferably 1 μm or more. Since the compressive stress layer has such a thickness, even if a deep crack occurs in the glass-ceramic substrate, crack extension and substrate fracture can be suppressed. Therefore, the thickness of the compressive stress layer is preferably 1 μm or more, more preferably 5 μm or more, and most preferably 8 μm or more.

The microcrystalline glass substrate of the present invention preferably has a vickers hardness (Hv) of 600 or more. With such hardness, occurrence of scratches can be suppressed, and mechanical strength can be improved. Therefore, the microcrystalline glass of the present invention has a vickers hardness (Hv) of preferably 600 or more, more preferably 650 or more, and most preferably 700 or more.

In the glass ceramic substrate of the present invention, it is preferable that the glass ceramic substrate is not broken even if 32g of steel balls are dropped from a height of 500mm to the glass ceramic substrate. Since the protective member has such impact resistance, it can withstand an impact when dropped or collided when used as a protective member. Therefore, the falling height at which the glass-ceramic substrate is not broken even when 32g of the steel ball is dropped is preferably 500mm or more, more preferably 650mm or more, and most preferably 800mm or more.

The three-point bending strength of the crystallized glass substrate of the present invention is preferably 450 Mpa. With such three-point bending strength, the glass will not break when subjected to sufficient pressure. Therefore, the three-point bending strength is preferably 450MPa or more, more preferably 600MPa or more, and most preferably 800MPa or more.

The microcrystalline glass of the present invention can be prepared by the following method: the raw materials are uniformly mixed according to the proportion range of the components, the uniform mixture is put into a crucible made of platinum or quartz, the melting is carried out for 5 to 24 hours in an electric furnace or a gas furnace within the temperature range of 1250 to 1550 ℃ according to the melting difficulty of the glass composition, the mixture is stirred to be uniform, then the temperature is reduced to proper temperature and the mixture is cast into a mould, and the mixture is slowly cooled to obtain the glass.

The glass of the glass ceramics of the present invention can be molded by a known method.

The glass-ceramic of the present invention is obtained by subjecting the glass raw material to crystallization treatment after molding or after molding processing, and uniformly precipitating crystals in the glass. The crystallization may be performed in 1 stage or 2 stages, but the crystallization is preferably performed in 2 stages. The treatment of the nucleation process is performed at the 1 st temperature, and then the treatment of the crystal growth process is performed at the 2 nd temperature higher than the nucleation process temperature. The crystallization process performed at the 1 st temperature is referred to as a 1 st crystallization process, and the crystallization process performed at the 2 nd temperature is referred to as a 2 nd crystallization process.

In order to obtain desired physical properties of the glass ceramics, preferred heat treatment conditions are:

the above-mentioned crystallization treatment is performed in 1 stage, and the nucleus formation process and the crystal growth process can be continuously performed. That is, the temperature is raised to a predetermined crystallization temperature, and after reaching the heat treatment temperature, the temperature is maintained for a certain period of time, and then the temperature is lowered. The temperature of the crystallization treatment is preferably 500 to 700 ℃, and the holding time at the crystallization treatment temperature is preferably 550 to 680 ℃, and is preferably 0 to 8 hours, and more preferably 1 to 6 hours, in order to precipitate a desired crystal phase.

When the crystallization is performed in 2 stages, the 1 st temperature is preferably 500 to 700 ℃, and the 2 nd temperature is preferably 650 to 850 ℃. The holding time at the temperature of 1 st is preferably 0 to 24 hours, and most preferably 2 to 15 hours. The holding time at the 2 nd temperature is preferably 0 to 10 hours, and most preferably 2 to 5 hours.

The above-mentioned holding time of 0 minutes means that the temperature is lowered or raised less than 1 minute after the temperature is reached.

The glass or glass ceramics of the present invention can be produced into a glass molded product by a method such as grinding or polishing. The glass-ceramic substrate based on the glass-ceramic of the present invention can be produced by processing a glass molded product into a thin plate. However, the method for producing the glass shaped material is not limited to these methods.

The microcrystalline glass substrate can be prepared into various shapes by adopting methods such as hot bending or pressing at a certain temperature, wherein the hot bending temperature and the pressing temperature are lower than the crystallization temperature. However, the method for producing various glass shapes is not limited to these methods.

The crystallized glass of the present invention can improve mechanical properties by precipitation crystallization and can obtain higher strength by forming a compressive stress layer. The formation method of the compression stress layer comprises a chemical toughening method, namely: an alkali component present in the surface layer of the glass-ceramic substrate is subjected to an exchange reaction with an alkali component having a larger ionic radius than the alkali component, thereby forming a compressive stress layer in the surface layer. There are also an ion implantation method for implanting ions into the surface layer of the glass-ceramic substrate and a thermal tempering method for heating and then rapidly cooling the glass-ceramic substrate.

Examples of the invention (tables 1 to 7) were prepared by the following method: firstly, selecting raw materials of various components, respectively corresponding oxides, hydroxides, carbonates, nitrates, fluorides, chlorides, hydroxides, metaphosphoric acid compounds and other raw materials, uniformly mixing the raw materials according to the component proportion range, putting the uniform mixture into a crucible made of platinum or quartz, melting the mixture in an electric furnace or a gas furnace at 1250-1550 ℃ for 5-24 hours according to the melting difficulty of glass composition, stirring the mixture uniformly, cooling the mixture to a proper temperature, casting the mixture into a mold, and slowly cooling the mixture to obtain raw glass.

The obtained raw glass was subjected to heat treatment in 1 stage or 2 stages for core formation and crystallization, respectively, to produce glass ceramics, in which examples 15, 18, 20 and 22 were subjected to heat treatment in 1 stage, and the other examples were subjected to heat treatment in 2 stages. In tables 1 to 7, the heat treatment conditions of the 1 st stage are recorded in the column of "nucleation process", the heat treatment conditions of the 2 nd stage are recorded in the column of "crystallization process", and the temperature of the heat treatment and the holding time at the temperature thereof are as shown in the tables.

In the examples, the crystal phase of the crystallized glass before chemical tempering was analyzed by an X-ray diffraction analyzer from the angle of the peak shown on the X-ray diffraction pattern.

Cutting and grinding the prepared microcrystalline glass to obtain a sheet with the specification of 36 multiplied by 29 multiplied by 0.7mm, polishing the opposite surfaces in parallel, and soaking the polished microcrystalline glass in KNO₃And carrying out chemical toughening in the molten salt to obtain the microcrystalline glass substrate. Wherein, the temperature for soaking the molten salt and the soaking time are shown in the column of 'chemical toughening conditions' in the table.

And (3) measuring the compressive stress value of the surface of the microcrystalline glass substrate subjected to chemical tempering and the thickness of the compressive stress layer by using a glass surface stress meter FSM-6000. The refractive index of the sample was 1.53, and the optical elastic constant was 28.5[ (nm/cm)/MPa.

The Vickers hardness of the crystallized glass substrate in the examples was calculated by dividing the load (N) when a diamond quadrangular pyramid indenter having an included angle of 136 degrees with respect to the opposing surface was pressed into a pyramid-shaped indentation on the test surface by the surface area (mm) calculated from the length of the indentation²) The values of (b) indicate (a). The test load was set to 100(N) and the holding time was set to 15 (sec). For the example with "chemical tempering conditions", this is done on the substrate after chemical tempering.

The ball drop height in the examples is the maximum ball drop height at which 32g of steel balls are dropped from a predetermined height after both surfaces of a 36X 29X 0.8mm substrate are polished and placed on a rubber sheet, and the substrate can withstand an impact without breaking. Specifically, the test was conducted starting from a ball drop height of 650mm, and the height was changed by 700mm, 750mm, 800mm, 850mm and 900mm without breaking. For the examples having the "chemical tempering condition", the substrate after chemical tempering was used as a test object. The test data recorded as 900mm in the examples shows that the steel ball was dropped from the height of 900mm and the substrate was not broken and received the impact.

The three-point bending strength in tables 1 to 7 was measured by using a microcomputer controlled electronic universal tester CMT6502, a glass specification of 36X 29X 0.7mm, and ASTM C158-.

The thermal conductivities of the microcrystalline glasses in tables 1 to 7 were measured by a thermal conductivity measuring instrument LFA 447. The JC/T675-1997 test method for thermal conductivity of glass materials Standard was carried out with room temperature (25 ℃) and the sample specification of Φ 12.7mm × 1.5mm as the measurement conditions.

The color in the examples is the color of a 36X 29X 0.8mm glass sheet observed by naked eyes.

TABLE 1

TABLE 2

TABLE 3

TABLE 4

TABLE 5

TABLE 6

TABLE 7

The above examples show that the heat conductivity of the microcrystalline glass of the invention at room temperature (25 ℃) is more than 2W/m.k, the microcrystalline glass has high heat conductivity, better bending strength and hardness, and good anti-falling damage performance, and meanwhile, the microcrystalline glass of the invention also has good individual color. The microcrystalline glass or the substrate obtained by the invention is suitable for protection components of portable electronic equipment, optical equipment and the like, and is particularly used as a rear cover plate.

Claims

1. A glass ceramic characterized by containing Li₂Si₂O₅Crystal phase and quartz solid solution as main crystal phase, and their total content is less than 50% but not more than 35% of microcrystalline glass in weight%, and its composition contains Na in weight%₂O 4～12％，Li₂O/Na₂O is 0.8 to 8.

2. The glass-ceramic according to claim 1, characterized in that its composition comprises, in weight%: SiO 2₂ 60～80％；Al₂O₃ 4～20％；Li₂O 0～15％；K₂O 0～5％；ZrO₂Greater than 0 but less than or equal to 5%; p₂O₅ 0～5％；TiO₂ 0～6％。

3. The glass-ceramic according to claim 1, further comprising: b is₂O₃0 to 5 percent; and/or MgO 0-2%; and/or 0-2% of ZnO; and/or 0-5% of CaO; and/or 0-5% of BaO; and/or 0-3% of FeO; and/or SnO₂0-2%; and/or 0-5% of SrO; and/or La₂O₃0 to 10 percent; and/or Y₂O₃0 to 10 percent; and/or Nb₂O₅0 to 10 percent; and/or Ta₂O₅0 to 10 percent; and/or WO₃ 0～5％。

4. The microcrystalline glass is characterized by comprising the following components in percentage by weight: SiO 2₂ 60～80％；Al₂O₃ 4～20％；Li₂O 0～15％；Na₂O 4～12％；ZrO₂Greater than 0 but less than or equal to 5%; p₂O₅ 0～5％；TiO₂0～6％；B₂O₃ 0～5％；K₂O 0～5％；MgO 0～2％；ZnO 0～2％；CaO 0～5％；BaO 0～5％；FeO 0～3％；SnO₂ 0～2％；SrO 0～5％；La₂O₃ 0～10％；Y₂O₃ 0～10％；Nb₂O₅ 0～10％；Ta₂O₅ 0～10％；WO₃0 to 5 percent; 0-5% of a clarifying agent and containing Li₂Si₂O₅Crystal phase and quartz solid solution as main crystal phase, the total content of which in the microcrystalline glass accounts for no more than 50% of the weight of the microcrystalline glass, and Li₂O/Na₂O is 0.8 to 8.

5. The glass-ceramic according to any one of claims 1 to 4, wherein SiO is SiO₂65-78%; and/or Al₂O₃5-18%; and/or Li₂0-12% of O; and/or Na₂4-10% of O; and/or ZrO₂0.4-3%; and/or P₂O₅0.4-3%; and/or TiO₂0.5-5%; and/or B₂O₃0 to 4 percent; and/or K₂0.5-4% of O; and/or MgO is greater than 0 but less than or equal to 2%; and/or ZnO is greater than 0 but less than or equal to 2%; and/or 0-4% of CaO; and/or 0-4% of BaO; and/or 0-1% of FeO; and/or SnO₂0.01-1%; and/or 0-3% of SrO; and/or La₂O₃0 to 9 percent; and/or Y₂O₃0 to 9 percent; and/or Nb₂O₅0-8%; and/or Ta₂O₅0-8%; and/or WO₃0-2%; and/or the fining agent comprises As₂O₃、Sb₂O₃、CeO₂And 0 to 5% of one or more selected from the group consisting of F, Cl, NOx and SOx.

6. The glass-ceramic according to any one of claims 1 to 4, wherein SiO is SiO₂/Li₂O is 4-10; and/or ZrO₂/Li₂O is 0 to 0.5; and/or Al₂O₃/(Na₂O+Li₂O) is 0.5 to 2; and/or ZrO₂+P₂O₅+TiO₂0.5 to 10%.

7. The glass-ceramic according to any one of claims 1 to 4, wherein SiO is SiO₂68-75%; and/or Al₂O₃6-15%; and/or Li₂6-10% of O; and/or Na₂4-8% of O; and/or ZrO₂0.8-2%; and/or P₂O₅0.8-2%; and/or TiO₂1-4%; and/or B₂O₃0 to less than 2 percent; and/or K₂0.8-3% of O; and/or 0-3% of CaO; and/or 0-3% of BaO; and/or SnO₂0.05-0.4%; and/or 0-1% of SrO; and/or La₂O₃Greater than 0 but less than or equal to 8%; and/or Y₂O₃Greater than 0 but less than or equal to 8%; and/or Nb₂O₅0 to 5 percent; and/or Ta₂O₅0 to 5 percent; and/or WO₃0 to 1 percent; and &Or 0-2% of a clarifying agent.

8. The glass-ceramic according to any one of claims 1 to 4, wherein SiO is SiO₂/Li₂O is 4.5 to 9.5; and/or ZrO₂/Li₂O is greater than 0 but less than 0.35; and/or Al₂O₃/(Na₂O+Li₂O) is 0.7 to 1.8; and/or Li₂O/Na₂O is 1.5 to 7.5; and/or ZrO₂+P₂O₅+TiO₂1 to 8 percent.

9. The glass-ceramic according to any one of claims 1 to 4, wherein Al is₂O₃7-15%; and/or ZrO₂1-2%; and/or P₂O₅1-2%; and/or TiO₂1.5-4%; and/or K₂1-3% of O; and/or 0-1% of CaO; and/or 0-1% of BaO; and/or SnO₂0.05-0.2%; and/or 0-1% of a clarifying agent; and/or SiO₂/Li₂O is 5-9; and/or ZrO₂/Li₂O is greater than 0 but less than or equal to 0.30; and/or Al₂O₃/(Na₂O+Li₂O) is 1 to 1.5; and/or Li₂O/Na₂O is 2-7; and/or ZrO₂+P₂O₅+TiO₂2 to 6 percent.

10. The glass-ceramic according to any one of claims 1 to 4, wherein Na is present₂O is greater than 5% but less than or equal to 8%; and/or Li₂O/Na₂O is 2 to 6.

11. The glass-ceramic according to any one of claims 1 to 3, further comprising NiO and/or Ni₂O₃The total amount is not more than 6%, and the lower limit of the total amount is not less than 0.1%; or contains Pr₂O₅The content is not more than 8 percent, and the lower limit of the content is more than 0.4 percent; or containing CoO and/or Co₂O₃The total amount is not more than 2%, and the lower limit of the total amount is not less than 0.05%;or containing Cu₂O and/or CeO₂The total amount is not more than 4%, and the lower limit of the total amount is not less than 0.5%; or containing Fe₂O₃The content is not more than 8%; or containing Fe₂O₃And CoO, CoO not exceeding 0.3%; or containing Fe₂O₃And Co₂O₃，Co₂O₃Not more than 0.3%; or containing Fe₂O₃CoO and NiO; or containing Fe₂O₃、Co₂O₃And NiO; or containing Fe₂O₃CoO and Co₂O₃Wherein, CoO and Co₂O₃The lower limit of the total amount is more than 0.2 percent; or containing Fe₂O₃CoO, NiO and Co₂O₃(ii) a Or containing MnO₂The content is not more than 4 percent, and the lower limit of the content is more than 0.1 percent; or containing Er₂O₃The content is not more than 8 percent, and the lower limit of the content is more than 0.4 percent; or containing Nd₂O₃The content is not more than 8 percent, and the lower limit of the content is more than 0.4 percent; or containing Er₂O₃、Nd₂O₃And MnO₂，Er₂O₃Content within 6% of Nd₂O₃Content within 4%, MnO₂The content is within 2 percent, and the lower limit of the total amount is more than 0.9 percent; or containing Cr₂O₃The content is not more than 4 percent, and the lower limit of the content is more than 0.2 percent; or contain V₂O₅The content is not more than 4%, and the lower limit of the content is more than 0.2%.

12. The glass-ceramic according to any one of claims 1 to 3, further comprising NiO and/or Ni₂O₃The total amount is not more than 4%; or contains Pr₂O₅The content is not more than 6%; or containing CoO and/or Co₂O₃The total amount is not more than 1.8%; or containing Cu₂O and/or CeO₂The total amount is not more than 3%; or containing Fe₂O₃The content is not more than 5%; or containing MnO₂The content is within 3 percent; or containing Er₂O₃The content is within 6 percent; or containing Nd₂O₃The content is within 6 percent; or containing Cr₂O₃The content is not more than 3%; or contain V₂O₅The content is not more than 3%.

13. The glass-ceramic according to any one of claims 1 to 3, further comprising NiO and/or Ni₂O₃The total amount is not more than 3%; or contains Pr₂O₅The content is not more than 5%; or containing Fe₂O₃The content is not more than 3%; or containing Cr₂O₃The content is not more than 2%; or contain V₂O₅The content is not more than 2%.

14. The microcrystalline glass according to any of claims 1-4, characterised in that Li₂Si₂O₅The crystalline phase accounts for more than or equal to 20% but less than 35% of the weight of the microcrystalline glass.

15. The microcrystalline glass according to any of claims 1-4, characterised in that Li₂Si₂O₅The crystalline phase accounts for 20-30% of the weight of the microcrystalline glass.

16. The microcrystalline glass according to any of claims 1-4, characterised in that Li₂Si₂O₅The crystalline phase accounts for 20-25% of the weight of the microcrystalline glass.

17. The glass-ceramic according to any one of claims 1 to 4, wherein the quartz and the quartz solid solution crystal phase account for 15% or more and less than 30% by weight of the glass-ceramic.

18. A crystallized glass according to any one of claims 1 to 4, wherein the quartz and the quartz solid solution crystal phase account for 20 to 29% by weight of the crystallized glass.

19. A glass-ceramic according to any one of claims 1 to 4, wherein the quartz and quartz solid solution crystal phases constitute 25 to 29% by weight of the glass-ceramic.

20. The microcrystalline glass according to any of claims 1-4, characterised in that said Li₂Si₂O₅The total content of the crystal phase and the quartz and quartz solid solution in the microcrystalline glass is 48% or less by weight of the microcrystalline glass.

21. The microcrystalline glass according to any of claims 1-4, characterised in that said Li₂Si₂O₅The total content of the crystal phase and the quartz and quartz solid solution in the microcrystalline glass is 46% by weight or less based on the weight of the microcrystalline glass.

22. The glass-ceramic according to any one of claims 1 to 4, wherein LiAlSi is used₄O₁₀The crystal phase accounts for no more than 15 percent of the weight of the microcrystalline glass.

23. A glass-ceramic according to any one of claims 1 to 4, characterized in that the upper limit of the glass liquidus temperature is 1450 ℃.

24. A glass-ceramic according to any one of claims 1 to 4, characterized in that the upper limit of the liquidus temperature of the glass is 1400 ℃.

25. A glass-ceramic according to any one of claims 1 to 4, characterized in that the upper limit of the liquidus temperature of the glass is 1380 ℃.

26. A glass-ceramic according to any one of claims 1 to 4, characterized in that the upper limit of the liquidus temperature of the glass is 1320 ℃.

27. A glass-ceramic according to any one of claims 1 to 4, characterized in that the glass has a thermal conductivity of 2 w/m-k or more at 25 ℃ at room temperature.

28. A glass-ceramic substrate, which is made by chemically toughening the glass-ceramic according to any one of claims 1 to 27.

29. The microcrystalline glass substrate according to claim 28, wherein the vickers hardness Hv is 600kgf/mm²The above.

30. The glass-ceramic substrate according to claim 28, wherein the vickers hardness Hv is 650kgf/mm²The above.

31. The glass-ceramic substrate according to claim 28, wherein the vickers hardness Hv is 700kgf/mm²The above.

32. The glass-ceramic substrate according to claim 28, wherein 32g of steel balls are dropped from a height of 500mm toward the glass-ceramic substrate without breaking.

33. The glass-ceramic substrate according to claim 28, wherein 32g of steel balls are dropped from a height of 650mm toward the glass-ceramic substrate without breaking.

34. The glass-ceramic substrate according to claim 28, wherein 32g of steel balls are dropped from a height of 800mm toward the glass-ceramic substrate without breaking.

35. The crystallized glass substrate according to claim 28, wherein the three-point bending strength is 450Mpa or more.

36. The crystallized glass substrate according to claim 28, wherein the three-point bending strength is 600Mpa or more.

37. The crystallized glass substrate according to claim 28, wherein the three-point bending strength is 800Mpa or more.

38. The crystallized glass substrate according to claim 28, wherein a compressive stress layer having a compressive stress value of 300Mpa or more is formed by an ion exchange treatment.

39. The crystallized glass substrate according to claim 28, wherein a compressive stress layer having a compressive stress value of 400Mpa or more is formed by an ion exchange treatment.

40. The crystallized glass substrate according to claim 28, wherein a compressive stress layer having a compressive stress value of 500Mpa or more is formed by an ion exchange treatment.

41. The crystallized glass substrate according to any one of claims 38 to 40, wherein the thickness of the compressive stress layer is 1 μm or more.

42. The crystallized glass substrate according to any one of claims 38 to 40, wherein the thickness of the compressive stress layer is 5 μm or more.

43. The crystallized glass substrate according to any one of claims 38 to 40, wherein the thickness of the compressive stress layer is 8 μm or more.