WO2020088221A1

WO2020088221A1 - Glass plate and manufacturing method therefor, and electronic device

Info

Publication number: WO2020088221A1
Application number: PCT/CN2019/110799
Authority: WO
Inventors: 欧阳辰鑫; 唐中帜; 吕旺春; 司合帅
Original assignee: 华为技术有限公司
Priority date: 2018-10-29
Filing date: 2019-10-12
Publication date: 2020-05-07
Also published as: CN111099827A; CN111099827B

Abstract

Provided are a glass plate and a manufacturing method therefor. The glass plate is a multiphase composite formed of a microcrystalline phase and a glass phase, and comprises a first surface and a second surface opposite to each other, the ratio value of the microcrystalline phase to the glass phase inside the glass plate tending to increase in gradient from the first surface to the second surface. When the glass plate is manufactured as a glass cover plate of an electronic device, the first surface thereof can be manufactured as an outer surface of the glass cover plate, and the second surface can be manufactured as an inner surface of the glass cover plate. A glass cover plate, manufactured using the glass plate, of an electronic device has a high fall-damage resistance while having a high intrinsic strength, thereby being able to improve the fall-damage resistance of the electronic device.

Description

Glass plate, manufacturing method thereof, and electronic equipment

Technical field

This application relates to the field of electronics and communication technology, in particular to the field of anti-fall housing technology.

Background technique

As consumers' requirements for the drop resistance of electronic devices such as mobile phones continue to increase, glass covers used in electronic devices are required to have good drop resistance.

In recent years, the use of chemically strengthened glass as the mainstream trend for glass cover plates of electronic equipment, because after the glass passes "chemical strengthening" or "toughening", a certain depth of compressive stress layer is formed on the glass surface, thereby improving the strength and resistance of the glass Wrestling.

However, in view of the ultra-thin trend of glass cover plates, the current mature chemical strengthening and physical strengthening process methods have been unable to significantly improve the strength of ultra-thin glass cover plates. Therefore, more and more research is focused on glass-ceramics (or "glass ceramics"), because glass-ceramics is a material that contains both crystal phase and glass phase by controlling glass crystallization during the manufacturing process. It also has the advantages of high transparency of glass and high strength of ceramics, and provides an effective way to improve the drop resistance of ultra-thin glass cover.

Summary of the invention

In view of this, the present application provides a glass plate made of glass-ceramics and a manufacturing method thereof to improve the drop resistance of the glass plate, and thereby improve the drop resistance of electronic devices.

In addition, based on the glass plate provided above, the present application also provides an electronic device including the glass plate.

In order to achieve the above purpose of the invention, the present application adopts the following technical solutions:

A first aspect of the present application provides a glass plate including a first surface and a second surface opposite to each other, the glass plate is a multi-phase composite formed by a microcrystalline phase and a glass phase, wherein, from the first The surface is facing the second surface, and the ratio of the microcrystalline phase to the glass phase inside the glass plate is gradually increasing.

When the glass plate provided in the first aspect of the present application is made into a glass cover of an electronic device, its first surface can be made into the outer surface of the glass cover, and the second surface can be made into the inner surface of the glass cover. In this glass substrate, from the first surface to the second surface of the glass plate, the ratio of the microcrystalline phase to the glass phase inside the glass plate is gradually increasing. Therefore, near the outer surface area of the glass cover, the glass phase content is large, so it is conducive to enhancing the chemical strengthening of the glass, which is conducive to improving the drop resistance of the glass cover, and near the inner surface area of the glass cover, slightly The crystal phase content is relatively large, so that the glass cover plate has a higher intrinsic strength. Therefore, the glass cover of the electronic device made of the glass plate provided by the present application has higher intrinsic strength and higher fall resistance, thereby improving the fall resistance of the electronic device.

As a possible implementation manner of the present application, the glass plate includes two or more glass-ceramic layers.

As a possible implementation manner of the present application, from the first surface to the second surface, the microcrystalline phase and the glass phase in each layer of the microcrystalline glass layer are uniformly distributed.

As a possible implementation manner of the present application, from the first surface to the second surface, the ratio of the crystallite phase to the glass phase in each layer of the crystallized glass layer increases gradually.

As a possible implementation manner of the present application, from the first surface to the second surface, the rate of increase of the ratio of the microcrystalline phase to the glass phase inside the glass plate is constant, or, from the From the first surface to the second surface, the rate of increase of the ratio of the microcrystalline phase to the glass phase inside the glass plate gradually increases; or, from the first surface to the second surface, the inside of the glass plate The rate of increase of the ratio of the microcrystalline phase to the glass phase gradually decreases.

As a possible implementation manner of the present application, the material system of the glass plate is at least one system of soda lime glass, aluminosilicate glass, soda aluminosilicate glass, lithium aluminosilicate glass, or phosphoaluminosilicate glass.

A second aspect of the present application provides a method of manufacturing a glass sheet, the method comprising: forming an initial glass sheet according to a material formula; the initial glass sheet includes first and second opposing surfaces; The first surface and the second surface of the initial glass sheet are heat-treated under different temperature conditions, so that the crystallinity of the first surface of the initial glass sheet is less than the crystallinity of the second surface, thereby obtaining a final glass sheet.

The manufacturing method can make glass plates with different crystallinities on different surfaces by controlling the heat treatment temperature conditions on different surfaces. Therefore, the manufacturing process of the glass plate is relatively simple, which is beneficial to reduce the process cost.

A third aspect of the present application provides an electronic device, including an electronic component and a glass cover plate covering the electronic component, the glass cover plate is a glass plate provided by any possible implementation manner of the first aspect above, The first surface of the glass plate is the outer surface of the glass cover plate, and the second surface of the glass plate is the inner surface of the glass cover plate; wherein, the inner surface is close to the electronic component The surface of the glass cover plate. The outer surface is a surface of the glass cover plate away from the electronic components.

In this electronic device, the glass cover plate is the glass plate provided in any possible implementation manner of the first aspect above, and the first surface of the glass plate is the outer surface of the glass cover plate. The second surface is the inner surface of the glass cover plate, and since the first surface to the second surface of the glass plate, the ratio of the microcrystalline phase to the glass phase inside the glass plate is gradually increasing. In this way, near the outer surface area of the glass cover, the glass phase content is large, so it is conducive to enhancing the chemical strengthening of the glass, which is conducive to improving the drop resistance of the glass cover, and in the area near the inner surface of the glass cover, slightly The crystal phase content is relatively large, so that the glass cover plate has a higher intrinsic strength. Therefore, the glass cover of the electronic device made of the glass plate provided by the present application has higher intrinsic strength and higher fall resistance. Therefore, the electronic device provided by the present application has higher fall resistance.

As a possible implementation manner of the present application, the glass cover includes a screen cover of an electronic device.

As a possible implementation manner of the present application, the glass cover plate includes a back cover plate of an electronic device.

As a possible implementation manner of the present application, the glass cover includes a screen cover and a back cover of an electronic device.

Compared with the prior art, this application has the following beneficial effects:

Based on the above technical solutions, it can be known that when the glass plate provided by the present application is made into a glass cover of an electronic device, the first surface can be made into the outer surface of the glass cover, and the second surface can be made into the inner surface of the glass cover . In this glass substrate, from the first surface to the second surface of the glass plate, the ratio of the microcrystalline phase to the glass phase inside the glass plate is gradually increasing. Therefore, near the outer surface area of the glass cover, the glass phase content is large, so it is conducive to enhancing the chemical strengthening of the glass, which is conducive to improving the drop resistance of the glass cover, and near the inner surface area of the glass cover, slightly The crystal phase content is relatively large, so that the glass cover plate has a higher intrinsic strength. Therefore, the glass cover of the electronic device made of the glass plate provided by the present application has higher intrinsic strength and higher fall resistance, thereby improving the fall resistance of the electronic device.

BRIEF DESCRIPTION

In order to clearly understand the specific embodiments of the present application, the following will briefly describe the drawings used when describing the specific embodiments of the present application.

1A and 1B are schematic diagrams of the ion exchange process between glass and alkali metal molten salt with a larger ion radius;

2 is a schematic diagram of an internal structure of a glass plate provided by an embodiment of the present application;

FIG. 3 is a schematic diagram of a gradient type in which the ratio of the microcrystalline phase to the glass phase is increased according to an embodiment of the present application;

4 is a schematic diagram of the internal structure of another glass plate provided by an embodiment of the present application;

5 is a schematic diagram of the internal structure of yet another glass plate provided by an embodiment of the present application;

6 is a schematic flowchart of an implementation manner of a method for manufacturing a glass plate provided by an embodiment of the present application;

7 is a schematic flowchart of another implementation manner of the method for manufacturing a glass plate provided by an embodiment of the present application;

8 is a schematic structural diagram of an electronic device provided by an embodiment of the present application.

detailed description

Before introducing the specific embodiments of the present application, first introduce the technical terms used in describing the specific embodiments of the present application.

Chemically strengthened glass: refers to the glass that forms a certain depth of compressive stress layer (compressive stress layer) on the surface of the glass after being "chemically strengthened" or "toughened". The presence of the compressive stress layer improves the strength and drop resistance of the glass.

Among them, the specific process of "chemical strengthening" or "tempering" is as follows: the glass to be strengthened is immersed in an alkali metal molten salt (such as NaNO ₃ molten salt or KNO ₃ molten salt) filled with a large ionic radius, at the glass transition temperature (Tg), large radius alkali metal ions such as Na ⁺ or K ⁺ in the molten salt are exchanged with the small radius alkali metal Li ⁺ in the glass surface by ion exchange. The volume difference between the two after ion exchange makes the glass surface appear compressive stress. Generally speaking, the greater the depth of the compressive stress layer (DOL value), the more helpful it is to the glass's anti-fall performance.

Among them, as an example, FIGS. 1A and 1B show an ion exchange process between glass and an alkali metal molten salt with a larger ion radius.

Glass-ceramic refers to the addition of certain nucleating substances to the glass. Through heat treatment, light irradiation, or chemical treatment, a large number of tiny crystals are evenly precipitated in the glass to form a dense microcrystalline phase and a multiphase glass phase Complex.

At present, there are three main methods for preparing glass-ceramics: melting method, sintering method and sol-gel method. The melting method is to mix various oxide raw materials uniformly, add a certain amount of nucleating agent, and then melt at 1400 ℃-1600 ℃, obtain the desired glass shape by molding, and then perform heat treatment to form at an appropriate temperature Core, grow up, and finally prepare glass-ceramics.

The sintering method refers to that after mixing and melting various oxide raw materials, they are not directly shaped, but are subjected to water quenching to obtain glass slag, and then ball milling to obtain glass powder. Then, the glass powder is granulated and pressed into a green body, which is sintered and densified at an appropriate temperature to obtain glass-ceramic products.

The sol-gel method refers to using the desired organic substances such as metal alkoxides or metal inorganic substances such as acetates and nitrates as precursors, and using citric acid as a catalyst to hydrolyze the sol into a gel to condense After the glue is dried, the required glass powder is obtained, and then the molding and sintering processes are carried out to finally obtain the glass-ceramic product.

The flow of the above three methods is as follows:

Melting method: batching → melting → molding → heat treatment → glass-ceramic products;

Melting method: batching → melting → water quenching → ball milling → granulation → molding → sintering → glass-ceramic products;

Sol-gel method: ingredients → precursor → sol → gel → drying → molding → sintering → glass ceramic products.

The crystallized glass products obtained by the above three types of preparation methods have two common characteristics:

1) The glass undergoes nucleation and growth during sintering or heat treatment to precipitate crystal phases. These crystal phases are derived from the phase separation process of the glass phase. Because the glass phases are fully and uniformly mixed, the crystal phases are also uniformly distributed in the Among the materials.

2) Due to the existence of the crystal phase, the proportion of the glass phase is bound to be reduced, which will weaken the effect of chemical strengthening. Because the existence of the glass phase is a necessary condition for the chemical strengthening of the glass. The glass state is a channel for ion exchange. The more spacious the channel, the more obvious the ion exchange effect.

The specific implementation of this application is described below.

At present, the drop resistance of electronic devices is relatively poor. Taking mobile phones as an example, the drop height of mainstream product models on the market is very low, and they cannot exceed 1 meter.

The front cover or back cover of the screen of the electronic device can be made of glass. In this way, to improve the drop resistance of electronic devices, it is necessary to increase the drop resistance of glass panels used for the front cover or the back cover of the screens used to make the electronic devices.

However, the internal structure of the glass cover plate for electronic devices in the prior art is uniformly crystallized, and the distribution of the crystal phase and the glass phase in the structure is uniform. Although, the inner surface area of the glass cover plate due to the existence of the crystal phase, so that the intrinsic strength has been improved. But at the same time, due to the reduction of the glass phase on the outer surface of the glass cover, the chemical strengthening effect is weakened, and both the DOL and the surface compressive stress (Compressed stress (CS value)) are weakened, reducing the drop resistance.

It should be noted that, in the embodiments of the present application, the outer surface of the glass cover plate is the surface of the glass cover plate exposed to the air, which is a surface away from the internal structure of the electronic device, which can be directly touched by the user. The inner surface of the glass cover is the surface that is in contact with the internal structure of the electronic device and cannot be touched by the user.

In order to make the glass cover plate have higher intrinsic strength and higher fall resistance, the embodiments of the present application provide a glass plate, the material of the glass plate is microcrystalline glass, which is composed of microcrystalline phase Multiphase composite formed with glass phase. The distribution of the microcrystalline phase and the glass phase inside is uneven, and from the first surface to the second surface of the glass plate, the ratio of the microcrystalline phase and the glass phase inside the glass plate shows a gradient increasing trend. As such, when the glass plate is made into a glass cover of an electronic device, its first surface can be made into the outer surface of the glass cover, and the second surface can be made into the inner surface of the glass cover.

Because in the crystallized glass, the presence of the glass phase is a necessary condition for the chemical strengthening of the glass. The glass phase is the ion exchange channel of the chemical strengthening process. The more glass phases, the wider the ion exchange channel, the more obvious the ion exchange effect. The greater the depth of the stress layer, the better the drop resistance of the glass. The presence of microcrystalline phase will increase the intrinsic strength of the glass. Therefore, when the glass plate provided by the present application is made into a glass cover of an electronic device, its first surface can be made into the outer surface of the glass cover, and the second surface can be made into the inner surface of the glass cover. In this glass substrate, from the first surface to the second surface of the glass plate, the ratio of the microcrystalline phase to the glass phase inside the glass plate is gradually increasing. Therefore, near the outer surface area of the glass cover, the glass phase content is large, so it is conducive to enhancing the chemical strengthening of the glass, which is conducive to improving the drop resistance of the glass cover, and near the inner surface area of the glass cover, slightly The crystal phase content is relatively large, so that the glass cover plate has a higher intrinsic strength. Therefore, the glass cover of the electronic device made of the glass plate provided by the present application has higher intrinsic strength and higher fall resistance, thereby improving the fall resistance of the electronic device.

As an implementation manner of the present application, a schematic diagram of the internal structure of the glass plate provided by the present application may be as shown in FIG. 2. In Fig. 2, black dots indicate crystallites in the glass plate. It can be seen from FIG. 2 that the microcrystalline phase inside the glass plate provided by the present application is unevenly distributed in the glass phase, and the proportion of the microcrystalline phase is gradient from the first surface S1 to the second surface S2 of the glass plate Increasing trend.

It should be noted that, in the embodiments of the present application, the gradient of the gradient increase tendency of the ratio of the microcrystalline phase to the glass phase may be a constant value, a continuously increasing change value, or a continuously decreasing change value. More specifically, this gradient type may be as shown in FIG. 3.

Among them, curve 1 indicates that the gradient increases continuously, which means that the rate of increase of the ratio of the microcrystalline phase to the glass phase gradually increases from the first surface to the second surface, and curve 2 indicates that the gradient is a constant value, which indicates that the gradient On the surface, the rate of increase of the ratio of the microcrystalline phase to the glass phase to the second surface does not change. Curve 3 shows that the gradient continuously decreases, which means that from the first surface to the second surface, the rate of increase of the ratio of the microcrystalline phase to the glass phase gradually decreases.

It should be noted that, in the embodiments of the present application, the glass plate may be composed of a layer of glass-ceramics, as shown in FIG. 2. The crystallinity distribution inside the glass-ceramic layer is not uniform, and the crystallinity tends to increase from the first surface to the second surface, so that from the first surface to the second surface, inside the glass plate The ratio of the microcrystalline phase to the glass phase is gradually increasing.

As another implementation of the present application, the glass plate may include two layers of glass-ceramics. As an example, the glass plate shown in FIG. 4 includes two layers of glass-ceramics layers, which in turn include a first glass-ceramics layer 41 and a second glass-ceramics layer 42 stacked in order from the first surface S1 to the second surface S2. The crystallinity of the first glass-ceramic layer 41 is less than the crystallinity of the second glass-ceramic layer 42, so the ratio of the crystallite phase to the glass phase in the first glass-ceramic layer 41 is smaller than that of the second glass-ceramic The ratio of the crystallite phase to the glass phase in the layer 42, so that the glass plate shown in FIG. 4 from the first surface S1 to the second surface S2, the ratio of the crystallite phase to the glass phase inside the glass plate The value is gradually increasing.

As an optional example of the present application, the crystallinity at various positions inside the first glass-ceramic layer 41 may be the same, so that the crystallite phase and the glass phase in the interior are uniformly distributed. Similarly, the crystallinity inside the second crystallized glass layer 42 is uniform, and therefore the crystallite phase and the glass phase inside thereof are uniformly distributed.

As another optional example of the present application, from the first surface to the second surface of the glass plate, the crystallinity inside the first glass-ceramic layer 41 and the second glass-ceramic layer 42 gradually increases, so that each layer of crystallites The ratio of the microcrystalline phase to the glass phase in the glass layer is increasing gradually.

As another implementation manner of the present application, the glass plate may include two or more glass-ceramic layers. As an example, FIG. 5 shows a glass plate including 5 glass-ceramic layers. Specifically, the glass plate includes a first glass-ceramic layer 51 to a fifth glass-ceramic layer 55 stacked in order from the first surface S1 to the second surface S2. Among them, the crystallinity of the first glass-ceramic layer 51 to the fifth glass-ceramic layer 55 increases in sequence, so that from the first glass-ceramic layer 51 to the fifth glass-ceramic layer 55, the crystallite phase and the glass phase The ratio value shows a gradient increasing trend.

Similar to the glass plate shown in FIG. 4 above, the crystallinity at each position inside each layer of glass-ceramic layer can be the same, so the crystallite phase inside it and the glass phase are uniformly distributed.

As another optional example of the present application, from the first surface S1 to the second surface S2 of the glass plate, the crystallinity inside each layer of crystallized glass layers gradually increases, so that the crystallite phase in each layer of crystallized glass layers The ratio with the glass phase shows a gradient increasing trend.

The above is a specific implementation manner of the glass plate provided by the embodiment of the present application. In the glass plate provided above, the material system may be soda lime glass, aluminosilicate glass, soda aluminum silicon glass, lithium aluminum silicon glass or phosphorous aluminum silicon glass At least one system.

Based on the specific implementation manner of the glass plate provided by the foregoing embodiment, the present application also provides a specific implementation manner of the manufacturing method of the glass plate.

Referring to FIG. 6, the manufacturing method of the glass plate provided by the embodiment of the present application includes the following steps:

S601: Various glass raw tapes with different crystallization capacities are made according to different material formulas.

It should be noted that, in the embodiments of the present application, a plurality of glass green tapes with different crystallization capabilities can be made using the same or different manufacturing process conditions according to multiple material recipes. Among them, the composition of each glass green tape may be different.

As an example, the method of making a glass green tape according to a material formula specifically includes the following steps:

S6011: Batch material preparation: Configure the raw materials used to manufacture the glass plate according to the material formula.

This step may be specifically as follows: configuring raw materials such as aluminum oxide, silicon oxide, magnesium oxide, calcium oxide, zinc oxide, alkali metal oxide, and nucleating agent according to a certain ratio.

S6012: Glass melting: The prepared raw materials are put into a melting furnace and melted to obtain a glass liquid.

This step may be specifically: putting the above-configured raw materials into a melting furnace, melting at a high temperature, obtaining a high-temperature glass liquid, and simultaneously removing bubbles and foreign substances in the glass liquid.

S6013: Water quenching: Pour the glass liquid into normal temperature water, perform water quenching to obtain glass slag.

This step may be specifically: after the high-temperature glass liquid obtained above is subjected to heat preservation, it is quickly poured into water, and water quenching is performed to obtain glass slag.

S6014: Ball milling: ball milling the glass slag to obtain glass powder.

This step may be specifically: using a glass component-related medium as a ball milling medium (such as alumina corundum balls), ball milling the glass slag obtained by water quenching to obtain glass powder.

S6015: sieving and grading: sieving and sieving the glass powder to obtain glass powder that satisfies the required particle size distribution.

S6016: Pulp making: Taking the glass powder satisfying the required particle size distribution as a basic material, adding an auxiliary agent, mixing, and obtaining a glass paste.

This step may be specifically: using the glass powder satisfying the required particle size distribution as a basic material, adding a certain proportion of solvent, plasticizer, binder, etc., and fully mixing in the batching machine to obtain glass slurry.

S6017: Glass green tape: Cast molding the glass paste to obtain a glass green tape.

This step can be specifically: using glass paste as a raw material, casting molding on a casting machine (scraper casting machine or coating casting machine, etc.) to make a continuous glass green tape, and according to the required size Cut sheets of glass tape.

S602: Stacking: According to the gradient requirement of the ratio of microcrystalline phase to glass phase, according to the order of crystallinity, multiple glass green tapes with different crystallization capacities are stacked and pressed together.

S603: Debinding.

This step can be specifically as follows: placing the laminated product in a debinding furnace and keeping it warm at a certain temperature, the purpose is to decompose and remove the polymer substances such as solvents, plasticizers, and binders mixed in the pulping process.

S604: Sintering.

This step may be specifically as follows: in the sintering furnace, the product is sintered according to the designed heating curve and heat preservation curve. Due to the different crystallization capabilities of glass green ribbons with different material formulations, in the same sintering environment, various glass green ribbons inside the product will exhibit different degrees of crystallization and long cores, that is, different sizes of crystallinity.

S605: Post-processing.

This step may be specifically: the products obtained in the above steps are subjected to processes such as grinding, CNC machine tool processing, and polishing to obtain an initial glass sheet whose appearance size meets the design requirements of the end product.

S606: Chemical strengthening treatment.

This step may be specifically: placing the initial glass plate in a salt bath furnace and performing heat treatment below the glass transition temperature, and ion exchange of a large radius alkali metal ion in the molten salt with a small radius alkali metal ion in the surface of the initial glass plate The surface area of the initial glass sheet forms a compressive stress layer of a specific depth, thereby obtaining the final glass sheet. The final glass plate obtained was excellent in drop resistance.

The manufacturing method of the glass plate provided by the present application will be further described in detail below through specific embodiments. The following embodiments are only examples of this application, and should not be construed as limitations to this application.

Example 1

As an example, the material composition of the method for manufacturing a glass plate provided in Example 1 takes the lithium aluminum silicon system as an example, and the material formulation uses three material formulations as an example for description. Set the three material formulas as: material A, material B, material C.

The manufacturing method of the glass plate shown in this embodiment includes the following steps:

Step 1: Batch preparation

According to the mass ratio calculation, the material A contains 55% SiO ₂ , 25% Al ₂ O ₃ , 12% Na ₂ O, 7% Li ₂ O, and 1% TiO ₂ , with TiO ₂ as the main nucleating agent.

Material B contains 55% SiO ₂ , 25% Al ₂ O ₃ , 11% Na ₂ O, 7% Li ₂ O, and 2% TiO ₂ .

Material C contains 55% SiO ₂ , 25% Al ₂ O ₃ , 10% Na ₂ O, 7% Li ₂ O, and 3% TiO ₂ .

Step 2: Glass melting

The raw materials of the above three components are melted in a high-temperature melting furnace at a temperature of 1500 ° C-1600 ° C for a time of 4h-6h to obtain a high-temperature glass liquid.

Step 3: Water quenching

After the above three kinds of high-temperature glass liquid of the material side are kept in heat, they are quickly poured into water and quenched with water to obtain three kinds of glass slag.

Step 4: Ball mill

The three kinds of glass slag obtained by water quenching are placed in corundum ball mill jars respectively, the ball milling medium is anhydrous ethanol, the ball-to-material ratio is 5-10, the rotation speed is 400 rpm-600 rpm, after 4-8h ball milling Glass frit with particle size distribution ranging from 1 μm to 8 μm is obtained.

Step 5: Screening and classification

The above three kinds of glass frit are separately sieved and classified to obtain glass frit A, glass frit B, and glass frit C with a particle size distribution of 0.5 μm-4 μm.

Step 6: Pulp making

Use 3 kinds of glass frit A, B and C as the basic materials, add a certain proportion of solvents, plasticizers, binders, etc., and fully mix in the batching machine for 2-6h to prepare suitable coating flow Three types of glass paste for the machine.

It should be noted that the selection of the types and contents of solvents, plasticizers, and binders are closely related to the functional parameters of the casting machine in the next step. For example, using isobutanol with a mass fraction of 50% -70% as a solvent, 10% -20% polyvinyl acetal butyral (PVB) as a binder, and 10% -20% polyethylene glycol as a plasticizer Agent.

Step 7: Glass raw tape

Three kinds of glass pastes are used as raw materials, and cast molding is performed on a coating-type casting machine, etc., to make a continuous glass green tape with a thickness of 10-70 μm. Then cut into glass green tape A, glass green tape B, and glass green tape C with a size of 180mm╳100mm.

Step 8: Stacking

5-100 sheets of green tape A, 5-100 sheets of green tape B, and 5-100 sheets of green tape C are sequentially stacked and pressed in order from top to bottom to obtain laminated glass plates.

Step 9: Debinding

The laminated glass plate obtained by laminating is debonded at 300 ° C-500 ° C for 2h-5h, and the auxiliary agents in the glass green tape, such as isobutanol, polyvinyl acetal butyraldehyde, and polyethylene glycol, are chemically decomposed and discharged.

Step 10: Sintering

Place the deglazed glass plate immediately at 700 ℃ -900 ℃ for sintering for 0.5h-1h. Due to the differences in the composition of the glass green tape A, the glass green tape B and the glass green tape C, the content of the nucleating agent is different, and different degrees of crystallization are performed to obtain glass plates with different crystallinities.

Step 11: Post-processing

The glass plates with different crystallinities obtained in the above steps are subjected to processes such as grinding, numerical control machine tool processing, and polishing to obtain an initial glass plate whose appearance size meets the design requirements of the end product.

Step 12: Chemical strengthening

Put the above three kinds of initial glass covers in 30% -50% KNO ₃ and 50% -90% NaNO ₃ molten salt molten salt, and perform ionization at 400 ℃ -600 ℃ under 2h-6h strengthening conditions Exchange to form compressive stress on the glass surface to increase the strength of the product.

The above is the specific implementation of the method for manufacturing a glass plate provided in Example 1 of the present application. In this specific implementation, three glass components with different crystallization capabilities are obtained by designing three kinds of glass components and then pulping and casting. According to the requirements of gradient design, three kinds of glass green tapes can be laminated regularly. In this embodiment, the glass component close to one surface of the glass plate (outer (upper) surface) has poor crystallization ability, and the glass component close to the other surface of the glass plate (inner (lower) surface) has excellent analysis.晶力。 Crystal capacity. During the sintering process, due to the difference in crystallization capacity, the glass plate exhibits a non-uniform, gradient distribution of crystallized glass ceramics. Moreover, the outer (upper) surface of the glass sheet has a relatively large amount of glass, which is conducive to the later chemical strengthening treatment and forms a deeper compressive stress layer through more effective ion exchange, which is conducive to improving the drop resistance of the glass sheet performance,

The glass plate made by this specific implementation mode has a certain regularity and gradient distribution of crystallization structure inside, instead of obtaining uniformly crystallized glass-ceramics in the prior art.

Example 2

As an example, the material composition of the glass plate manufacturing method provided in Example 2 takes the sodium-calcium system as an example, and the material formula is described by taking 5 material formulas as examples. Set three material formulas: material A, material B, material C, material D and material E.

Step 1: Batch preparation

According to mass ratio calculation, material A contains 70% SiO ₂ , 3% Al ₂ O ₃ , 12% Na ₂ O, 14% CaO ₂ , 1% (TiO ₂ + ZrO ₂ ), of which TiO ₂ + ZrO _{2 is} used Nucleating agent helps to remove the coloring problem of TiO ₂ .

Material B contains 70% SiO ₂ , 3% Al ₂ O ₃ , 11% Na ₂ O, 14% CaO ₂ , and 2% (TiO ₂ + ZrO ₂ ).

Material C contains 70% SiO ₂ , 3% Al ₂ O ₃ , 10% Na ₂ O, 14% CaO ₂ , and 3% (TiO ₂ + ZrO ₂ ).

The material D contains 70% SiO ₂ , 3% Al ₂ O ₃ , 9% Na ₂ O, 14% CaO ₂ , and 4% (TiO ₂ + ZrO ₂ ).

Material E contains 70% SiO ₂ , 3% Al ₂ O ₃ , 8% Na ₂ O, 14% CaO ₂ , and 5% (TiO ₂ + ZrO ₂ ).

Step 2: Glass melting

The raw materials of the above five components are melted in a high-temperature melting furnace at a temperature of 1500 ° C-1600 ° C for a time of 4h-6h to obtain a high-temperature glass liquid.

Step 3: Water quenching

After the above five kinds of high-temperature glass liquid of the material side are kept in heat, they are quickly poured into water and quenched by water to obtain five kinds of glass slag respectively.

Step 4: Ball mill

The specific process conditions of this step are the same as the ball mill process conditions in Example 1. For the sake of brevity, they will not be repeated here. For details, please refer to Example 1.

Step 5: Screening and classification

The glass powder is sieved and classified to obtain glass powder A, glass powder B, glass powder C, glass powder D, and glass powder E with a particle size distribution of 0.5 μm-4 μm.

Step 6: Pulp making

Take 5 kinds of glass powder as basic materials, mix with 50% -70% isobutanol as solvent, 10% -20% polyvinyl acetal butyral (PVB) as binder, 10% -20% As the plasticizer, the polyethylene glycol is fully mixed in the batching machine for 2-6 hours to prepare 5 kinds of glass paste suitable for the coating casting machine.

Step 7: Glass raw tape

Five kinds of glass pastes are used as raw materials, and casting is performed on a coating-type casting machine or the like to form a continuous glass green tape with a thickness of 10-70 μm. Then cut into glass green tape A, glass green tape B, glass green tape C, glass green tape D, glass green tape E with the size of 180mm╳100mm.

Step 8: Stacking

Put 3-50 glass green tapes A, 3-50 glass green tapes B, 3-50 glass green tapes C, 3-50 glass green tapes D, 3-50 glass green tapes E from top to bottom The order of stacking and pressing are in order to obtain laminated glass plates.

Step 9: Debinding

The specific process conditions of this step are the same as the debinding process conditions in Example 1. For the sake of brevity, they will not be repeated here. For details, please refer to Example 1.

Step 10: Sintering

The specific process conditions of this step are the same as the sintering process conditions in Example 1. For the sake of brevity, they will not be repeated here. For details, please refer to Example 1.

Step 11: Post-processing

The specific process conditions of this step are the same as the post-treatment process conditions in Embodiment 1. For the sake of brevity, they will not be repeated here. For details, please refer to Embodiment 1.

Step 12: Chemical strengthening

The specific process conditions of this step are the same as the chemical strengthening process conditions in Example 1. For the sake of brevity, they will not be repeated here. For details, please refer to Example 1.

The above is the specific implementation of the method for manufacturing a glass plate provided in Example 2 of the present application. In this specific implementation, five glass components with different crystallizing capabilities are obtained by designing five kinds of glass components and then pulping and casting. The crystalline phase near the surface of the glass plate (outer (upper) surface) is relatively high, which is conducive to improving the intrinsic strength of the glass plate, and the glass phase near the other surface of the glass plate (inner (lower) surface) is relatively high. This is conducive to obtaining higher CS and DOL values, and this asymmetric structure is more suitable for the ultra-thin trend of glass cover plates.

The glass plate manufactured by the specific implementation mode has a significant gradient crystallization structure inside the glass plate, and the difference in the proportion of the crystal phase in the crystallized glass is impossible to achieve in the prior art.

The above is an implementation manner of the glass plate manufacturing method provided by the embodiment of the present application. In this implementation manner, glass sheets made of multiple material formulations are laminated together to obtain glass plates with different crystallinity inside.

As an extension of the embodiments of the present application, the glass plate that obtains the internal crystallinity can also be realized by different heat treatment conditions, for details, refer to the following embodiments.

Referring to FIG. 7, another implementation manner of the glass plate manufacturing method provided by the embodiment of the present application includes the following steps:

S701: An initial glass plate is made according to a material formula; the initial glass plate includes opposing first and second surfaces.

It should be noted that the method for preparing the initial glass plate in this step may be the same as the method for preparing the glass green tape in the above-mentioned implementation.

For the sake of brevity, no more detailed description is provided here. For details, refer to the specific implementation manner of S601 in the foregoing implementation manners.

S702: Heat-treating the first surface and the second surface of the initial glass sheet under different temperature conditions so that the crystallinity of the first surface of the initial glass sheet is less than the crystallinity of the second surface, thereby obtaining a final glass sheet.

It should be noted that since the crystallinity of the material is related to the temperature during the crystallization process, the crystallinity of the material can be controlled by controlling the temperature during the crystallization process.

Therefore, in the embodiments of the present application, the two surfaces of the initial glass plate are heat-treated at different temperature conditions, so that the crystallinity of the two surfaces of the initial glass plate is different. Specifically, the crystallinity of the first surface of the initial glass sheet is made smaller than the crystallinity of the second surface, thereby obtaining a final glass sheet. The glass plate finally obtained has excellent anti-drop performance under the premise of higher intrinsic strength.

Based on the glass plate provided in the above embodiment, the present application also provides an electronic device.

Referring to FIG. 8, the electronic device provided by the embodiment of the present application includes: an electronic component 81, and a glass cover 82 covering the electronic component 81, wherein the glass cover 82 may be the glass plate described in any of the foregoing implementation manners , And the first surface of the glass plate is the outer surface of the glass cover 82, the second surface of the glass plate is the inner surface of the glass cover 82;

The inner surface is the surface of the glass cover close to the electronic component 81, and the outer surface is the surface of the glass cover far from the electronic component 82.

Since the distribution of the microcrystalline phase and the glass phase inside the glass plate is uneven, and from the first surface to the second surface of the glass plate, the ratio of the microcrystalline phase and the glass phase inside the glass plate shows a gradient increasing trend. Therefore, the glass cover 82 made of the glass plate has a higher microcrystalline phase content near the inner surface area of the glass cover, so that the glass cover has a higher intrinsic strength. The area near the outer surface of the glass cover plate has a higher glass phase content, which is conducive to enhancing the chemical strengthening effect of the glass and thus improving the drop resistance of the glass cover plate. Therefore, the glass cover of the electronic device provided in the embodiments of the present application has higher intrinsic strength and higher fall resistance, thereby improving the fall resistance of the electronic device.

It should be noted that the electronic device generally includes a front and a back, wherein the front is generally provided with a screen and the back is provided with a battery, wherein both the screen and the battery need to be protected by a cover plate. Therefore, as a specific example of this application, the glass cover plate 82 It may include the screen cover 821 of the electronic device or the back cover 822 of the electronic device. In addition, the glass cover 82 may include both the screen cover 821 and the back cover 822 of the electronic device.

The above is the specific implementation manner provided by the embodiments of the present application.

Claims

A glass plate, characterized in that it includes a first surface and a second surface opposite to each other, the glass plate is a multi-phase composite formed by a microcrystalline phase and a glass phase, wherein On the second surface, the ratio of the microcrystalline phase to the glass phase inside the glass plate shows a gradient increasing trend.
The glass plate according to claim 1, wherein the glass plate comprises two or more glass-ceramic layers.
The glass plate according to claim 2, wherein from the first surface to the second surface, the microcrystalline phase and the glass phase in each layer of the microcrystalline glass layer are uniformly distributed.
The glass plate according to claim 2, characterized in that, from the first surface to the second surface, the ratio of the microcrystalline phase to the glass phase in each layer of the microcrystalline glass layer increases in a gradient trend.
The glass plate according to any one of claims 1 to 4, wherein from the first surface to the second surface, the rate of increase of the ratio of the microcrystalline phase to the glass phase inside the glass plate is constant constant,

Or, from the first surface to the second surface, the rate of increase of the ratio of the microcrystalline phase to the glass phase inside the glass plate gradually increases;

or,

From the first surface to the second surface, the rate of increase of the ratio of the microcrystalline phase to the glass phase inside the glass plate gradually decreases.
The glass plate according to any one of claims 1 to 5, characterized in that the material system of the glass plate is soda lime glass, aluminosilicate glass, soda aluminosilicate glass, lithium aluminosilicate glass or phosphoaluminosilicate glass At least one system.
A method for manufacturing a glass plate, characterized in that the method includes:

Making an initial glass plate according to a material formula; the initial glass plate includes opposing first and second surfaces;

The first surface and the second surface of the initial glass sheet are subjected to heat treatment under different temperature conditions, so that the crystallinity of the first surface of the initial glass sheet is less than the crystallinity of the second surface, thereby obtaining a final glass sheet.
An electronic device, characterized by comprising electronic components and a glass cover plate covering the electronic components, the glass cover plate is the glass plate according to any one of claims 1-6, the glass plate The first surface is the outer surface of the glass cover plate, and the second surface of the glass cover is the inner surface of the glass cover plate;

Wherein, the inner surface is a glass cover plate surface close to the electronic component, and the outer surface is a glass cover plate surface far away from the electronic component.
The electronic device according to claim 8, wherein the glass cover comprises a screen cover of the electronic device.
The electronic device according to claim 8, wherein the glass cover comprises a back cover of the electronic device.
The electronic device according to claim 8, wherein the glass cover comprises a screen cover and a back cover of the electronic device.