CN107162409B

CN107162409B - Glass and preparation method thereof

Info

Publication number: CN107162409B
Application number: CN201710480229.3A
Authority: CN
Inventors: 肖子凡; 何浩波; 刘攀; 邓臻禄; 戴斌
Original assignee: Shenzhen Csg Applied Technology Co ltd; CSG Holding Co Ltd
Current assignee: Shenzhen Csg Applied Technology Co ltd; CSG Holding Co Ltd
Priority date: 2017-06-22
Filing date: 2017-06-22
Publication date: 2020-09-08
Anticipated expiration: 2037-06-22
Also published as: CN107162409A

Abstract

The invention discloses glass and a preparation method thereof, and relates to the technical field of glass. One embodiment of the glass comprises: the glass comprises the following components in percentage by mass on the basis of oxides: SiO 2₂，57％～66％；Al₂O₃，12％～20％；MgO，3％～8％；Na₂O，10％～16％；K₂O，0.5％～6.5％；ZrO₂，0.1％～1.5％；Fe₂O₃0.001 to 0.01 percent. The embodiment enables the glass to have the capability of naturally resisting tin penetration under the condition of ensuring that other properties meet the requirements; ion exchange treatment can be directly carried out; the ion exchanged glass is not easy to warp.

Description

Glass and preparation method thereof

Technical Field

The invention relates to the technical field of glass, in particular to glass and a preparation method thereof.

Background

Float glass is formed on the surface of molten tin bath, the environment in the tin bath is relatively complex, and a three-phase system of molten glass, molten tin and protective gas of the tin bath exists. In the production process of float glass, the glass is shaped, polished and cooled on the surface of molten tin. Theoretically, the pure molten tin and glass have a wetting angle of 175 degrees at a temperature of about 1000 ℃, and are not substantially wetted. H is always led into the tin bath to ensure that the tin liquid is not oxidized₂+N₂The protective gas, however, inevitably has spaces connected to the outside air at the inlet and outlet of the tin bath, or the tin bath is oxidized to form SnO or SnO due to impure components of the protective gas₂Sn in tin liquid at high temperature²⁺Or Sn⁴⁺Ion-exchange with alkali metal ions in the glass network, thereby enabling Sn²⁺Or Sn⁴⁺Migrate into the lower surface of the glass and form a tin-infiltrated layer. When ion exchange is carried out on glass with more tin penetration, the ion exchange degrees of the upper surface and the lower surface of the glass are greatly different due to the existence of the tin penetration layer, so that the glass is warped, and the application of the glass is limited.

In the prior art, the tin infiltration amount of the lower surface of the glass in the float production process is mostly reduced by changing the working condition parameters of a tin bath or from the perspective of protecting tin liquid from being oxidized, and the method for reducing the tin infiltration amount has the advantages of complex process, difficult operation and high production cost. In the prior art, tin infiltration is reduced by increasing the iron content, but the increase of the iron content can greatly reduce the transmittance of the glass, so that the use experience of the cover plate glass is greatly influenced.

Disclosure of Invention

In view of this, embodiments of the present invention provide a glass and a method for manufacturing the same, which can make the glass have the ability to naturally resist the following tin impregnation and reduce the warpage after ion exchange.

In order to achieve the above object, according to an aspect of an embodiment of the present invention, there is provided a glass including, in terms of mass percent on an oxide basis:

SiO₂，57％～66％；

Al₂O₃，12％～20％；

MgO，3％～8％；

Na₂O，10％～16％；

K₂O，0.5％～6.5％；

ZrO₂，0.1％～1.5％；

Fe₂O₃，0.001％～0.01％。

optionally, the glass further comprises, on an oxide basis: an oxide of tin.

Optionally, the glass comprises, in mass percent on an oxide basis: SnO₂，0.001％～0.05％。

Optionally, the glass of the present invention further comprises, on an oxide basis: an oxide of a rare earth metal.

Optionally, the oxide of a rare earth metal comprises at least one of: CeO (CeO)₂，Nd₂O₃，Sm₂O₃，Er₂O₃。

Optionally, 0.01% Fe ≦ Fe by mass percent₂O₃+SnO₂+CeO₂+Nd₂O₃+Sm₂O₃+Er₂O₃≤0.15％。

Optionally, 72% SiO 2 by mass percentage₂+Al₂O₃≤82％。

Optionally, 0.48. ltoreq.0.981 Al by mass₂O₃/(1.062K₂O+1.613Na₂O)≤0.8。

Optionally, 0.5 ≦ (1.062K) by mass₂O+2.481MgO+0.811ZrO₂)/(1.613Na₂O+0.6262Fe₂O₃)≤1.3。

Optionally, the glass comprises, in mass percent on an oxide basis:

SiO₂57% -63%; and/or the presence of a gas in the gas,

Al₂O₃15% -18%; and/or the presence of a gas in the gas,

ZrO₂0.3% -1%; and/or the presence of a gas in the gas,

Fe₂O₃，0.005％～0.008％。

optionally, the glass does not include, on an oxide basis: boron oxide and/or calcium oxide.

Optionally, the glass comprises, in mass percent on an oxide basis:

SiO₂，57％；

Al₂O₃，17.9757％；

MgO，6.3867％；

Na₂O，12.7050％；

K₂O，4.3826％；

ZrO₂，1.5％；

SnO₂，0.01％；

Fe₂O₃，0.006％；

CeO₂，0.0085％；

Sm₂O₃，0.017％；

Er₂O₃，0.0085％。

according to another aspect of the present invention, there is provided a method of making glass comprising:

forming a molten glass raw material, and annealing to obtain the glass; the glass raw material is adjusted to a raw material capable of forming a composition of the low tin-infiltrated ultra-white float glass of the present invention.

Optionally, forming by a float method, wherein the groove pressure of the float forming is less than 15Pa, and the average dew point is higher than-10 ℃.

Optionally, the method of making glass of the present invention further comprises: and carrying out ion exchange treatment on the annealed glass.

One embodiment of the above invention has the following advantages or benefits: the glass has proper components and contents, so that the glass has the capability of naturally resisting the tin impregnation under the surface under the condition of ensuring that other properties meet the requirements; the glass can be directly subjected to ion exchange treatment without the need of back-end treatment processes such as surface polishing treatment and the like, and the glass after ion exchange is not easy to warp.

Further effects of the above-mentioned non-conventional alternatives will be described below in connection with the embodiments.

Detailed Description

The following description of exemplary embodiments of the invention, including various details of the embodiments of the invention to facilitate understanding, should be construed as merely illustrative. Accordingly, those of ordinary skill in the art will recognize that various changes and modifications of the embodiments described herein can be made without departing from the scope and spirit of the invention. Also, descriptions of well-known functions and constructions are omitted in the following description for clarity and conciseness.

In the present invention, each component of the glass is represented by an oxide as a reference, and the content of each component is represented by mass percentage of the oxide. The term "based on oxides" is a method in which all of oxides, nitrates, and the like used as raw materials of the glass composition of the present invention are decomposed and converted into oxides during melting, and the contents of the respective components contained therein are expressed; "expressed in terms of mass percent of oxides" is the amount of each component contained in the glass, based on 100% of the total mass of the oxides formed.

Unless otherwise indicated, a range of numerical values set forth includes both the upper and lower limits of the range, as well as any range between the stated ranges. It should also be understood that the various features disclosed in this specification may be used in any and all combinations.

The glass comprises the following components on the basis of oxides: SiO 2₂，Al₂O₃，MgO，Na₂O，K₂O，ZrO₂，Fe₂O₃。

SiO₂Is a main oxide for forming glass, and can improve the mechanical strength, chemical stability, thermal stability and the like of the glass. If SiO₂The content of (b) is less than 58%, the integrity and stability of the glass network are reduced, and the tin-penetration resistance is greatly reduced; due to SiO₂Is a relatively difficult substance to melt if SiO₂The content of (B) exceeds 66%, the melting temperature of the glass is increased, and melting and refining become difficult. Thus, SiO in the present invention₂The content is preferably in the range of 57% to 66%, more preferably 57% to 63%.

Al₂O₃The glass is a component for improving weather resistance, enables a glass network structure to be more complete, can reduce the crystallization tendency of glass, and improves the chemical stability, thermal stability, mechanical strength and hardness of the glass. In aluminosilicate glasses, Al₂O₃Can participate in forming an aluminum-oxygen network, so that the glass structure is more complete. Higher content of Al₂O₃The tin-penetration resistance of the glass can be obviously improved; al (Al)₂O₃The aluminum-oxygen network has larger network space and can improve the performance of the glass after ion exchange. But excessive Al₂O₃The melting temperature and liquidus temperature of the glass are significantly increased, and the meltability of the glass is deteriorated. Therefore, Al in the present invention₂O₃The content of (b) is preferably 12 to 20%, more preferably 15 to 18%.

MgO is a network exo-oxide. When the content of MgO is not more than 8%, the MgO is beneficial to reducing the melting point of the glass, improving the uniformity, increasing the hydrolysis resistance, enabling the glass to tend to be stable, improving the durability of the glass, preventing the glass from crystallizing, improving the elastic modulus of the glass and inhibiting the occurrence of cracks. At the same time, Mg²⁺Has strong ion potential and can greatly weaken alkali metal ions and Sn in the tin liquor²⁺Or Sn⁴⁺And exchange, and strengthen the tin penetration resistance of the glass. However, if the MgO content is higher than 8%, the glass is easily devitrified; if MgO is less than 3%, the viscosity of the glass melt increases and the meltability decreases, and the resistance of the glass to tin bleeding becomes weak due to the lack of oxygen-donating ability. Therefore, the MgO content is preferably in the range of 3% to 8% in the present invention.

The calcium oxide is a component having the same properties as MgO, and can improve meltability, prevent glass from devitrification, and impart a certain resistance to tin bleeding to the glass. However, it is considered that in alkali-containing aluminosilicate glasses, the ion exchange rate of the glass may be decreased by the oxide of calcium. Thus, in some alternative embodiments, the glasses of the present invention do not contain oxides of calcium, such as CaO.

Na₂O is a component for promoting the melting of glass raw materials, can ensure that the glass has good ion exchange capacity, and ensures that the glass after ion exchange has larger compressive stress and surface compression layer depth. High content of Na₂O can significantly lower the melting and liquidus temperatures of the glass, but also dramatically increase the glassThe coefficient of thermal expansion of the glass and reduces the chemical stability of the glass. If Na is present₂When the content of O exceeds 16%, the broken bonds of the glass are increased, the network structure of the glass is incomplete, the resistance to tin bleeding is lowered, and the weather resistance and stability of the glass are also deteriorated. If it is less than 10%, the glass becomes difficult to melt, and the resistance of the glass to tin bleeding is lowered due to the lack of oxygen-donating ability in the composition of the glass body. Thus, Na in the present invention₂The optimal range of the O content is 10 to 16 percent.

K₂O is the same as Na₂O is a component of the same nature and can inhibit Na⁺With Sn in the tin liquor²⁺Or Sn⁴⁺And exchange, so that the glass has the capacity of resisting tin penetration. If K is₂The content of O is more than 6.5 percent, the network structure of the glass is incomplete, the water resistance and the weather resistance of the glass are deteriorated, and the ion exchange capacity and the tin penetration resistance of the glass are obviously reduced; if less than 0.5%, the glass melting effect is poor and Na inhibition is difficult⁺With Sn in the tin liquor²⁺Or Sn⁴⁺Exchange, resulting in a glass with less than ideal resistance to tin-bleed. Thus, in the present invention K₂The preferable range of O is 0.5 to 6.5%.

The boron oxide can reduce the melting temperature of the glass and improve the melting property of the glass, and meanwhile, the small amount of the boron oxide can also strengthen the network of the glass and improve the tin penetration resistance of the glass. However, if the glass contains boron oxide, the boron oxide is easily volatilized, and the glass may have a problem of non-uniform glass components, striae, erosion of furnace walls, and the like. Thus, in some alternative embodiments, the glasses of the present invention do not contain boron oxides, e.g., do not contain B₂O₃。

ZrO₂The glass is a component capable of increasing the compressive stress of the surface of the glass in the ion exchange process of the glass, can improve the hardness, the weather resistance and the stability of the glass, and has a certain function of reinforcing the network structure of the glass. ZrO (ZrO)₂Has high ion potential, and can inhibit Sn in molten tin²⁺Or Sn⁴⁺Exchange with ions in the glass, thereby improving the glassThe ability of the lower surface of the glass to resist tin wicking. But too much ZrO₂The melting temperature of the glass is increased, making it difficult to melt the glass and increasing the possibility of cracking the glass from the indentation. Thus, the ZrO contained in the present invention₂The range of (B) is 0.1% to 1.5%, preferably 0.3% to 1%.

In some alternative embodiments, the glasses of the present invention further comprise tin oxides, such as SnO₂. The tin oxide is a fluxing agent and a clarifying agent in the glass melting process, and can reduce the melting temperature of glass and improve the glass clarification quality. Tin naturally present in the glass, e.g. Sn²⁺Or Sn⁴⁺Will reduce Sn in the tin liquid²⁺Or Sn⁴⁺The dynamic force of the migration into the glass enables the glass to have certain tin penetration resistance. If the content of tin oxide is too low, a sufficient clarifying effect cannot be achieved; if the content is too high, the number of bubbles in the glass increases, the yield decreases, and tin is likely to precipitate as a metal. The oxide of tin in the present invention is SnO₂The content of the compound is 0.001 to 0.05 percent.

In some prior art, a certain amount of elementary iron is added into a tin liquid to solve the problem of tin diffusion on the lower surface of float glass. Theoretically, the reduction of iron is stronger than that of tin, and the addition of iron in the tin liquid can reduce tin oxide into simple substance tin, thereby reducing the tin infiltration amount of the glass. However, when the iron piece residue or the oxide of the iron piece in the molten tin is separated from the tin bath by the glass plate, the lower surface of the glass is scratched, and the yield of the glass is lowered.

In the prior art, the problem of tin infiltration on the lower surface of the glass is solved by increasing the content of iron in the glass. Small amount of Fe₂O₃The glass transmittance can be improved, and the heat permeability of the molten glass during melting, clarification, forming and annealing can be improved. At the same time, Fe₂O₃Can reduce Sn in the glass²⁺Oxidized to Sn⁴⁺So that the glass has certain tin penetration resistance. However, the iron content should not be too high to ensure the stability of the glass flow and the consistency of heat transmission and optical color. Too high Fe₂O₃The glass is colored, the transmittance of the glass is greatly reduced, and the usability of the glass is affected. The invention can improve the internal quality and the external quality of the glass by strictly controlling the iron content and the total iron/ferrous iron in the components. Since various raw materials in the production process are more or less contacted with the ironware container, iron is easily brought into the glass, and therefore, the cost of the raw materials is greatly increased due to the low content of the iron oxide. Fe contained in the invention₂O₃The range of (A) is 0.001 to 0.01%, preferably 0.005 to 0.08%.

Under the same temperature condition, the tin penetration amount of the lower surface of the glass is increased along with the increase of the residence time of the glass in the tin liquid. Therefore, in the prior art, the problem of tin diffusion on the lower surface of the glass is solved by reducing the stay time of the glass in a tin bath. This approach requires that the residence time of the glass in the tin bath be reduced as much as possible while ensuring production stability. However, the process of changing the working condition parameters of the tin bath is complex, the operation is difficult, and the stability of production is not facilitated.

In the float forming process, the better the sealing environment of the tin bath, the more the protective gas or the purer the components of the protective gas is, the more the tin bath can ensure that the tin liquor is not oxidized, thereby reducing the tin infiltration amount of the glass, and in addition, increasing the emission of the waste gas of the tin bath is also beneficial to reducing the tin infiltration amount of the glass. However, increasing the flow rate of the tin bath shielding gas, increasing the purity of the shielding gas, or increasing the discharge of tin bath waste gas requires increased costs, which is costly.

The tin penetration on the surface of the glass can restrict the application field of the glass, or the cost for manufacturing the product in the back end processing is increased for the glass with larger tin penetration amount. For glass with a large tin penetration amount, the prior art usually performs polishing treatment on the glass before use so as to reduce the influence caused by tin penetration. However, the added processing procedures greatly increase the use cost of the glass.

The glass has proper components and contents, so that the glass has the capability of naturally resisting tin penetration under the condition of ensuring that other properties meet the requirements; the low-tin-permeability ultra-white float glass can be directly subjected to ion exchange treatment without surface polishing and other back-end treatment processes, and has simple processing and using procedures and low cost; furthermore, the ion-exchanged glass is less likely to warp.

When natural white light is irradiated on glass, the composition of light transmitted through the glass is changed due to selective absorption, and the color of the glass is substantially complementary to the color of the absorbed light, i.e., the color of the transmitted light. The color exhibited by the glass is dependent on the material of the glass. In order to minimize the discoloration of the glass upon exposure to light and to increase the transmittance of the glass, in some alternative embodiments, the glasses of the present invention include rare earth oxides. The rare-earth metal oxide can complement the oxidizability of the glass and modify the colour tone of the glass, e.g. CeO₂Or Nd₂O₃Can inhibit the glass from changing color when meeting light. It should be noted that the present invention describes the various components of the glass on an oxide basis, and in order to maintain consistency in the manner described, the rare earth metals in the tin-infiltrated ultra-white float glass are described herein on an oxide basis. It will be understood by those skilled in the art that the rare earth metal need not be present in the glass of the present invention as an oxide. Preferably, the oxide of a rare earth metal comprises at least one of: CeO (CeO)₂、Nd₂O₃、Sm₂O₃、Er₂O₃For example, including CeO₂、Nd₂O₃、Sm₂O₃、Er₂O₃At least two of them.

In some alternative embodiments, CeO is included in the glass₂、Nd₂O₃、Sm₂O₃、Er₂O₃When oxides of rare earth metals and oxides of tin are equal to or less than 0.01 percent of Fe₂O₃+SnO₂+CeO₂+Nd₂O₃+Sm₂O₃+Er₂O₃Less than or equal to 0.15 percent of Sn can enter the glass²⁺Is oxidized to Sn⁴⁺And Sn⁴⁺Ion diffusion coefficient less than Sn²⁺Thereby reducing the tin penetration amount of the glass. Fe₂O₃+SnO₂+CeO₂+Nd₂O₃+Sm₂O₃+Er₂O₃When the value of (A) is less than 0.01%, the oxidation of ions in the glass cannot convert most of Sn²⁺Oxidation to Sn⁴⁺So that the effect of reducing tin penetration is greatly weakened; if the value is more than 0.15%, the glass is colored to some extent, so that the transmittance is greatly reduced, and the use of the glass is affected.

SiO₂、Al₂O₃Can participate in forming a silicon-oxygen network and an aluminum-oxygen network respectively, and the network structures can improve the ion exchange capacity and speed of the glass on one hand and can improve the thermal stability, hardness, impact resistance and other performances of the glass on the other hand. In some alternative embodiments, 72% ≦ SiO₂+Al₂O₃Less than or equal to 82 percent. When SiO in glass₂、Al₂O₃When the conditions are met, the network structure of the glass is more complete, the hardness and the chemical stability of the glass are guaranteed, and the tin penetration resistance is greatly improved. If SiO₂+Al₂O₃If the value of (a) is less than 72%, the network structure of the glass is incomplete, and the tin-infiltration resistance is greatly reduced; if the value is more than 82%, the melting, clarification, homogenization and the like of the glass are difficult, and the process difficulty and the production cost are increased.

In some alternative embodiments, 0.48 ≦ 0.981Al₂O₃/(1.062K₂O+1.613Na₂O) is less than or equal to 0.8. When Al in the glass₂O₃、K₂O、Na₂When O meets the above conditions, most alkali metal ions in the glass exist in a relatively complete network and are difficult to react with Sn in the tin liquid²⁺Or Sn⁴⁺The exchange is performed, thereby reducing the amount of tin penetration of the glass. If 0.981Al₂O₃/(1.062K₂O+1.613Na₂O) is less than 0.48, alumina is not enough to connect the silica network completely, the constraint on alkali metal ions is weakened, and the alkali metal ions are easier to be connected with Sn in the tin liquid²⁺Or Sn⁴⁺Carrying out exchange; if it is greater than 0.8, the glass will have a melting temperatureHigher, will increase the production cost, and if the alkali metal content is reduced, will weaken the ion exchange capacity of the glass greatly, reduce the performance of the glass.

In some alternative embodiments, 0.5 ≦ (1.062K)₂O+2.481MgO+0.811ZrO₂)/(1.613Na₂O+0.6262Fe₂O₃) Less than or equal to 1.3. Due to Sn²⁺、Sn⁴⁺Radius of (A) and Na⁺、Fe²⁺、Fe³⁺Are similar in radius, so that ion exchange between them occurs relatively easily. When K is in the glass₂O、MgO、ZrO₂、Na₂O、Fe₂O₃When the above conditions are satisfied, Na can be inhibited⁺、Fe²⁺、Fe³⁺And Sn in the tin liquid²⁺、Sn⁴⁺And exchanging to reduce the tin penetration amount of the glass. If (1.062K)₂O+2.481MgO+0.811ZrO₂)/(1.613Na₂O+0.6262Fe₂O₃) Is less than 0.5, this inhibiting Na⁺And Fe²⁺Or Fe³⁺With Sn in the tin liquor²⁺Or Sn⁴⁺The ability to exchange is greatly impaired; if the value is more than 1.3, the ion exchange ability of the glass is greatly impaired, and the use properties of the glass are lowered.

According to another aspect of the embodiments of the present invention, there is provided a method of manufacturing glass, including:

forming the molten glass raw material, and annealing to obtain the glass; the glass raw material is adjusted to be a raw material of a composition of any one of the low tin-permeability ultra-white float glasses of the invention. The internal stress of the glass can be eliminated by the annealing treatment.

In the process of producing glass, the respective constituents recited in the first aspect of the present invention may be used as raw materials. It will be appreciated by those skilled in the art that some physical and/or chemical changes may occur in the glass components during the process of making the glass, such that there is some difference between the composition of the raw material components and the composition of the finally made glass, and therefore, those skilled in the art may also use other raw material components as long as the raw material components are capable of forming the composition of the glass provided by the first aspect of the embodiments of the present invention.

The low tin-infiltrated super-white float glass may be formed into a sheet glass or a bulk glass according to the actual circumstances, and the present invention is not particularly limited thereto. For example, the tin-infiltrated ultra-white float glass is formed into a thin plate having a thickness of 1.5mm to 2mm and a plate width of about 1000mm by an edge roller.

The invention can adopt the float process to form the glass, the float process forming device can be selected according to the actual situation, and the invention is not specially limited to the method. In some alternative embodiments, the float forming has a channel pressure less than 15Pa and an average dew point greater than-10 ℃. Therefore, the environment that the tin bath is seriously polluted can be simulated as much as possible, so that the anti-tin-permeation performance of the glass can be conveniently inspected.

In some alternative embodiments, the method of making the glass of the present invention may further comprise: and carrying out ion exchange treatment on the annealed glass. The strength of the glass can be strengthened by ion exchange treatment, and the application range of the glass can be improved, and the glass can be applied to the fields of electronic cover glass and the like.

The ion exchange can be carried out by those skilled in the art using ion exchange liquids and ion exchange methods commonly used in the art, and the present invention is not particularly limited thereto.

To enhance the ion exchange effect, in some alternative embodiments, the annealed glass block may be cut, or the air side may be thinned, for example to 0.7mm, on a single side, or the air side may be polished to a mirror surface. In order to examine the tin-barrier resistance of the glass of the invention, the original tin-barrier surface was maintained during the various treatments of the glass.

The glass of the present invention and the method for producing the same are exemplified below based on some examples.

Examples 1 to 27

Weighing each raw material component of the glass, fully mixing in a mixer, putting into a platinum crucible, putting into a silicon-molybdenum rod heating type high-temperature furnace at 1650 ℃, melting for 6 hours, clarifying and homogenizing. Pouring the homogenized glass liquid into a micro float forming device, drawing the glass liquid into a thin plate with the thickness of 1.5 mm-2 mm and the plate width of about 1000mm by an edge roller at the temperature of 1100-900 ℃, drawing the formed glass plate into an annealing furnace, eliminating internal stress, and slowly cooling to room temperature to obtain the sheet low-tin-permeability ultra-white float glass with good surface flatness and roughness. The melting temperature, degradation temperature, transmittance and tin penetration amount of the lower surface of the glass were measured.

The amount of tin penetration was measured by XRF measurement (X-ray fluorescence spectroscopy). The measurement results are reported in the form of tin counts (KCPS). The KCPS is obtained by comparing the parameters of the tin ion characteristic peak of the detected target sample with the parameters of the tin ion characteristic peak of the unified standard sample, and thus has no unit. In the examples related to the present application, all the samples of the examples were compared with the same standard sample, and the larger the KCPS value, the higher the tin penetration amount, and the smaller the KCPS value, the lower the tin penetration amount.

And cutting the fully annealed glass, thinning the single surface of the air surface to 0.7mm, polishing the glass until the glass is a mirror surface, and keeping the original tin-related surface. The 0.7mm ultra-thin glass sheet was precision cut and machined with a Computer Numerical Control (CNC) machine to form 5.5 inch, 7 inch and 10 inch lids. And carrying out ion exchange chemical strengthening treatment to obtain strengthened cover plate glass, placing the strengthened cover plate glass on a flat marble detection table surface, and measuring the warping degree of each cover plate glass.

Tables 1, 2, 3 and 4 show the compositions of the glasses of examples 1-27 and the corresponding melting temperature, annealing temperature, transmittance, KCPS and warpage.

TABLE 1 compositions of glasses and measurement results in examples 1-8

TABLE 2 compositions of glasses and measurement results in examples 9 to 16

TABLE 3 compositions of glasses and measurement results in examples 17 to 24

TABLE 4 compositions of glasses and measurement results in examples 25 to 27

Remarking: in the tables 1 to 4, the following examples are given,

A＝SiO₂+Al₂O₃；

B＝0.981Al₂O₃/(1.062K₂O+1.613Na₂O)；

C＝(1.062K₂O+2.481MgO+0.811ZrO₂)/(1.613Na₂O+0.6262Fe₂O₃)；

D＝Fe₂O₃+SnO₂+CeO₂+Nd₂O₃+Sm₂O₃+Er₂O₃；

the transmittance is a glass sample having a thickness of 2mm in terms of thickness;

5.5 inch warp criteria: v is not more than 0.1mm in angularity, O is more than 0.1mm and not more than 0.15mm in angularity, and x is angularity more than 0.15 mm;

7 inch warp standard: v is not more than 0.2mm in angularity, O is more than 0.2mm and not more than 0.25mm in angularity, and x is angularity more than 0.25 mm;

standard for 10 inch warpage: v is not more than 0.3mm in warpage, O is not less than 0.3mm < 0.4mm in warpage, and x is more than 0.4mm in warpage.

From the data in tables 1-4, it can be seen that the glasses of examples 1-20 have smaller KCPS, i.e., better resistance to tin bleed, than those of examples 21-27 under the conditions that other properties are satisfactory; the degree of warp after ion exchange is smaller, for example, the degree of warp of a 5.5-inch cover plate is less than or equal to 0.15mm, the degree of warp of a 7-inch cover plate is less than or equal to 0.25mm, and the degree of warp of a 10-inch cover plate is less than or equal to 0.4 mm. The glass obtained in the above example in example 2 has the best tin-barrier capability, and the KCPS is only 0.39; the warpage after ion exchange is also very small, for example, the warpage of a 5.5 inch cover plate is less than or equal to 0.1mm, the warpage of a 7 inch cover plate is less than or equal to 0.2mm, and the warpage of a 10 inch cover plate is less than or equal to 0.3 mm.

Fe in example 21₂O₃0.1% SnO₂The content is 0. On the one hand, too high Fe₂O₃The transmittance of the glass was reduced, and on the other hand, SnO capable of improving the quality of glass refining was not contained in example 21₂Therefore, the transmittance of the glass in example 21 is significantly lower than the transmittance of the glasses in examples 1 to 20. In addition, as can be seen from the measurement results of examples 1 to 20 and example 21, the glass containing an oxide of a rare earth metal has a higher transmittance. In addition, the glass of this embodiment has a smaller warpage, for example, a warpage of 0.15mm or less for a 5.5 inch cover plate, a warpage of 0.25mm or less for a 7 inch cover plate, and a warpage of 0.4mm or less for a 10 inch cover plate.

In example 22, C is 0.3811, less than 0.5. Appropriate C value can inhibit Na⁺、Fe²⁺、Fe³⁺And Sn in the tin liquid²⁺、Sn⁴⁺And exchanging to reduce the tin penetration amount of the glass. C value is too low to inhibit Na⁺And Fe²⁺Or Fe³⁺With Sn in the tin liquor²⁺Or Sn⁴⁺The ability to exchange is impaired and, therefore, the KCPS of the glass in example 22 is significantly higher than that of the glasses in examples 1-20. When the glass of the embodiment is used for manufacturing the electronic cover plate, the warping degree is small, for example, the warping degree of the cover plate with the size of 5.5 inches is less than or equal to 0.15 mm.

In example 23, D is 0.0070 but less than 0.01. The proper D value can supplement the oxidation of the glass and is beneficial to Sn entering the glass²⁺Is oxidized to Sn⁴⁺And the tin penetration amount of the glass is reduced. The D value is too low, so that most Sn cannot be oxidized by ions in the glass²⁺Oxidation to Sn⁴⁺The effect of reducing the tin penetration is greatly weakened. Thus, the KCPS of the glasses in example 23 was significantly higher than the KCPS of the glasses in examples 1-20. When the glass of the embodiment is used for manufacturing the electronic cover plate, the warping degree is small, for example, the warping degree of the cover plate with the size of 5.5 inches is less than or equal to 0.15 mm.

In example 24, B is 0.3851, less than 0.48. Is suitably aThe B value can make the whole structure of the glass more dense and the anti-tin-penetration capability better. The B value is too low, alumina in the glass is not enough to completely connect a silica network, and the constraint on alkali metal ions is weakened, so that the alkali metal ions can be easily associated with Sn in the tin liquid²⁺Or Sn⁴⁺And carrying out exchange. Thus, the KCPS of the glasses in example 24 was significantly higher than the KCPS of the glasses in examples 1-20. Due to Al in example 24₂O₃Is relatively low and therefore the melting temperature of the glass is significantly lower than in the other examples. Although the warpage of the electronic cover plate manufactured by using the present embodiment is greater than the warpage of the electronic cover plate manufactured by using the glass in embodiments 1 to 20, the inventors found that when the electronic cover plate with a smaller size is manufactured by using the glass in the present embodiment, the warpage is small, and the requirement of the electronic device on the warpage of the cover plate can be satisfied.

From the measurement results of example 25, it can be seen that although the melting temperature of the glass is lowered, the glass has poor resistance to tin bleed. This is likely to have a higher SiO content than in this example₂And a lower content of Al₂O₃It is related. When the glass of the embodiment is used for manufacturing the electronic cover plate, the warping degree is large, for example, the warping degree of the 5.5-inch cover plate is larger than 0.15mm, the warping degree of the 7-inch cover plate is larger than 0.25mm, and the warping degree of the 10-inch cover plate is larger than 0.4 mm.

SiO in example 26₂And Al₂O₃Too low content of (A) and too high content of MgO, which leads to a glass having a low melting temperature, but the glass has a large KCPS and a weak resistance to tin bleeding. When the glass of the embodiment is used for manufacturing the electronic cover plate, the warping degree is large, for example, the warping degree of the 5.5-inch cover plate is larger than 0.15mm, the warping degree of the 7-inch cover plate is larger than 0.25mm, and the warping degree of the 10-inch cover plate is larger than 0.4 mm.

Al in example 27₂O₃Is too high and does not contain SnO₂Therefore, the glass has a high melting temperature and KCPS and is weak in tin penetration resistance. When the glass of the embodiment is used for manufacturing the electronic cover plate, the warping degree is large, for example, the warping degree of a 7-inch cover plate is larger than 0.25mm, and the warping degree of a 10-inch cover plate is larger than 0.4 mm.

The above-described embodiments should not be construed as limiting the scope of the invention. Those skilled in the art will appreciate that various modifications, combinations, sub-combinations, and substitutions can occur, depending on design requirements and other factors. Any modification, equivalent replacement, and improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. The glass is characterized by comprising the following components in percentage by mass on the basis of oxides:

SiO₂，57％～66％；

Al₂O₃，12％～20％；

MgO，3％～8％；

Na₂O，10％～16％；

K₂O，0.5％～6.5％；

ZrO₂，0.1％～1.5％；

Fe₂O₃，0.001％～0.01％；

the glass further comprises: oxides of tin and rare earth metals; the oxide of a rare earth metal comprises at least one of: CeO (CeO)₂，Nd₂O₃，Sm₂O₃，Er₂O₃；

According to the mass percentage, the Fe content is more than or equal to 0.01 percent₂O₃+SnO₂+CeO₂+Nd₂O₃+Sm₂O₃+Er₂O₃≤0.15％。

2. The glass according to claim 1, wherein the glass comprises, in mass percent on an oxide basis: SnO₂，0.001％～0.05％。

3. The glass of claim 1, wherein 72% SiO by mass₂+Al₂O₃≤82％。

4. The glass according to claim 1, wherein 0.48. ltoreq.0.981 Al by mass₂O₃/(1.062K₂O+1.613Na₂O)≤0.8。

5. The glass of claim 1, wherein 0.5. ltoreq (1.062K) by mass₂O+2.481MgO+0.811ZrO₂)/(1.613Na₂O+0.6262Fe₂O₃)≤1.3。

6. The glass according to claim 1, comprising, in mass percent on an oxide basis:

SiO₂57% -63%; and/or the presence of a gas in the gas,

Al₂O₃15% -18%; and/or the presence of a gas in the gas,

ZrO₂0.3% -1%; and/or the presence of a gas in the gas,

Fe₂O₃，0.005％～0.008％。

7. the glass according to claim 1, wherein the glass does not comprise oxides of boron and/or oxides of calcium on an oxide basis.

8. The glass according to claim 1, comprising, in mass percent on an oxide basis:

SiO₂，57％；

Al₂O₃，17.9757％；

MgO，6.3867％；

Na₂O，12.7050％；

K₂O，4.3826％；

ZrO₂，1.5％；

SnO₂，0.01％；

Fe₂O₃，0.006％；

CeO₂，0.0085％；

Sm₂O₃，0.017％；

Er₂O₃，0.0085％。

9. a method of making glass, comprising:

forming a molten glass raw material, and annealing to obtain the glass; the glass raw material is adjusted to a raw material capable of forming the composition of the glass according to any one of claims 1 to 8.

10. The method of claim 9, wherein the float forming is performed under a pressure of less than 15Pa and an average dew point of more than-10 ℃.

11. The method of claim 9, further comprising: and carrying out ion exchange treatment on the annealed glass.