Ion-absorbing glass product and preparation method thereof and ion strengthening process of lithium-containing microcrystalline glass

Abstract

The present invention discloses an ion-absorbing glass product, a preparation method, and an ion-strengthening process for lithium-containing glass-ceramics, belonging to the field of glass chemical strengthening. By designing the components of a basic glass composition and combining it with a rapid cooling and forming process, the invention produces an ion-absorbing glass product with ion-absorbing properties. The ion-absorbing glass product absorbs lithium ions that diffuse from the interior of the lithium-containing glass-ceramics into the salt bath during chemical strengthening. In particular, for high-lithium glass-ceramics with a lithium content of 20 mol% or more, the ion-absorbing glass product can maintain the stability of the salt bath composition, particularly the lithium ion content, thereby improving the efficiency and effectiveness of chemical strengthening of the glass-ceramics and enhancing the quality of the glass-ceramics.

Description

Technical Field

[0001] The present invention relates to the field of glass chemical strengthening, and in particular to an ion-absorbing glass product and a preparation method thereof, and an ion strengthening process for lithium-containing microcrystalline glass. Background Art

[0002] Glass preparation typically involves chemical strengthening through ion exchange processes, such as sodium-lithium and potassium-sodium ion exchange in the glass and crystalline phases. The salt bath used for ion exchange is typically composed of a specific ratio of components. During the ion exchange process, smaller alkali metal cations, such as lithium ions, continuously diffuse into the salt bath, while larger alkali metal cations in the salt bath enter the glass. However, as smaller alkali metal cations, such as lithium ions, continue to diffuse into the salt bath, the composition ratio of the salt bath changes. When the lithium ion concentration exceeds the required threshold, the ion strengthening effect of the glass can be reduced or the product dimensional expansion rate can be altered, thereby affecting product yield.

[0003] Currently, to stabilize the composition ratio of the salt bath, sampling and testing are commonly used. When the composition in the salt bath exceeds a threshold, the bath is drained and fresh salt is poured in to melt. This method causes process downtime, affecting production efficiency. Especially for the strengthening of glass-ceramics, due to the high requirements for lithium ion ratio stability, it may be necessary to replace the salt bath with each furnace, which is not economical. Alternatively, phosphate can be added to the salt bath to precipitate small cations, but this method is prone to crystallization on the product surface, resulting in defects, and the reaction is inefficient and time-consuming.

[0004] In addition, in order to prevent product defects caused by changes in the composition of the chemically strengthened salt bath, a solid purifier or ion sieve product is used. Most of these methods maintain the stability of the KNO3 content by controlling the absorption of sodium ions in the salt bath and the release and diffusion of potassium ions. These methods do not improve the impact of changes in the salt bath composition caused by lithium ions. Although some solid purifiers or ion sieve products have an adsorption effect on lithium ions and can reduce the content of lithium ions in the salt bath to a certain extent, they mainly manifest as the adsorption and removal of lithium ions in the salt bath. In actual work, it is very likely that the lithium ions introduced into the salt bath itself are also adsorbed and removed, and there is no mention of maintaining the stability of the lithium ion ratio in the salt bath. On the other hand, the ingredients of this type of product often contain some alkaline earth metal ions (such as Ca 2+ 、Zn 2+ Mg 2+ ), which is easily introduced into the molten salt at high temperature, hindering the ion exchange between K, Na, and Li, and then affecting the ion exchange efficiency of the product.

[0005] Therefore, there is an urgent need to develop a new absorbent or strengthening method to regulate the composition stability of the salt bath used in the chemical strengthening process of microcrystalline glass, especially the stability of the lithium ion content. Summary of the Invention

[0006] The main purpose of the present invention is to provide an ion-absorbing glass product and a preparation method and an ion strengthening process for lithium-containing microcrystalline glass, to regulate the absorption amount of lithium ions in the ion strengthening salt bath, and to solve the technical problem that during the ion strengthening process, the lithium ion component content in the salt bath is unbalanced, which easily affects the ion strengthening effect of the lithium-containing microcrystalline glass and thus affects its quality.

[0007] To achieve the above object, the present invention provides an ion-absorbing glass product, which comprises the following components calculated by molar percentage:

[0008] SiO2: 38 mol%~55 mol%,

[0009] Al2O3: 11mol%~21mol%,

[0010] Na2O: 28 mol%~42 mol%,

[0011] B2O3: 0.9mol%~2.1mol%,

[0012] ZrO2: 0.1mol%~1.2mol%,

[0013] Bi2O3: 0mol% ~ 0.6mol%,

[0014] Wherein, the components of the ion-absorbing glass product satisfy 0.16≤(n Al2O3 +2n B2O3 +n ZrO2 ) / (n Na2O +n SiO2 )≤0.35.

[0015] In some embodiments of the present application, the transition temperature Tg of the ion-absorbing glass article is ≤ 500°C.

[0016] In some embodiments of the present application, the ion-absorbing glass product comprises the following components, calculated by mole percentage:

[0017] SiO2: 38 mol%~52 mol%,

[0018] Al2O3: 12mol%~18mol%,

[0019] Na2O: 30 mol%~42 mol%,

[0020] B2O3: 0.9mol%~1.5mol%,

[0021] ZrO2: 0.1mol%~0.8mol%,

[0022] Bi2O3: 0 mol% ~ 0.3 mol%.

[0023] In some embodiments of the present application, the composition of the ion-absorbing glass product satisfies 0.16≤(n Al2O3 +2n B2O3 +n ZrO2 ) / (n Na2O +n SiO2 )≤0.3.

[0024] In some embodiments of the present application, the ion-absorbing glass product is in the shape of particles and / or plates.

[0025] In some embodiments of the present application, the ion-absorbing glass article has cracks on its surface.

[0026] In some embodiments of the present application, the ion-absorbing glass product is in the form of particles, and the particle size of the ion-absorbing glass product in the form of particles is 0.6 mm to 2 mm;

[0027] And / or, the ion-absorbing glass product is in a plate shape, and the thickness of the plate-shaped ion-absorbing glass product is 0.6 mm to 2 mm.

[0028] Furthermore, to achieve the above-mentioned object, the present invention further provides a method for preparing the ion-absorbing glass product of the present invention, the method comprising the following steps: cooling and forming a molten glass material by a rapid cooling forming method to obtain the ion-absorbing glass product.

[0029] In some embodiments of the present application, the cooling rate of the rapid cold forming is 80°C / 8-150°C / 8.

[0030] In some embodiments of the present application, the rapid cold forming method includes at least one of leaking water quenching, water-cooled inclined roller pressing, vertical pressing and horizontal pressing.

[0031] The present invention also provides an ion strengthening process for lithium-containing glass-ceramics, comprising the following steps: adding the ion-absorbing glass product of the present invention as described above to a salt bath for ion strengthening of the lithium-containing glass-ceramics.

[0032] In some embodiments of the present application, the lithium-containing glass-ceramics contains more than 20 mol% of Li2O calculated by mole percentage.

[0033] In some embodiments of the present application, based on the area of the lithium-containing glass-ceramics, the amount of the ion-absorbing glass product added is 526 g / m 2 ~960g / m 2 .

[0034] In some embodiments of the present application, the ion-absorbing glass product and the lithium-containing glass-ceramics enter and exit the salt bath together.

[0035] In some embodiments of the present application, the formula of the salt bath includes potassium salt, sodium salt and lithium salt.

[0036] In some embodiments of the present application, the amount of the lithium salt added is 0.1%-0.3%, based on the total content of the potassium salt and the sodium salt being 100%;

[0037] And / or, based on the total content of the potassium salt and the sodium salt being 100%, the content of the sodium salt is greater than or equal to 40% and less than 100%.

[0038] In some embodiments of the present application, during the ion strengthening process of the lithium-containing glass-ceramics, the fluctuation value of the lithium ion content in the salt bath is less than or equal to 60 ppm.

[0039] In some embodiments of the present application, the ion strengthening temperature of the lithium-containing glass-ceramics is 500° C.-550° C.;

[0040] And / or, the ion strengthening time of the lithium-containing microcrystalline glass is 5h-7h.

[0041] The beneficial effects that can be achieved by the present invention are:

[0042] The present invention designs the components of the glass base composition and cooperates with the rapid cooling molding process to obtain an ion-absorbing glass product with ion absorption function. The ion-absorbing glass product has the function of absorbing lithium ions that diffuse from the inside of the glass into the salt bath during chemical strengthening of the lithium-containing microcrystalline glass. It can maintain the component stability of the salt bath, especially the stability of the lithium ion content, thereby improving the efficiency and effect of chemical strengthening of the lithium-containing microcrystalline glass, and promoting the lithium-containing microcrystalline glass to obtain excellent stress distribution, thereby exerting stronger performance based on its intrinsic characteristics.

[0043] In addition, when chemically strengthening in a salt bath, the use of ion-absorbing glass products and microcrystalline glass in and out of the chemical salt bath at the same time is more conducive to regulating the amount of lithium ion absorption in the salt bath, avoiding excessive or insufficient absorption of lithium ions in the salt bath that leads to an imbalance in the lithium ion composition, and achieving stability of the lithium ion composition in the salt bath. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying any creative work.

[0045] Figure 1 FIG2 is a schematic diagram of a process for preparing an ion-absorbing glass product according to an embodiment of the present invention.

[0046] The purpose, features and advantages of the present invention will be further described with reference to the accompanying drawings and in conjunction with the embodiments. DETAILED DESCRIPTION

[0047] It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0048] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

[0049] In the present invention, descriptions such as "first" and "second" are for descriptive purposes only and should not be understood as indicating or implying their relative importance or implicitly indicating the number of the technical features indicated. Therefore, features defined as "first" or "second" may explicitly or implicitly include at least one of such features. In addition, the technical solutions of various embodiments may be combined with each other, but this must be based on the fact that they can be implemented by a person of ordinary skill in the art. If the combination of technical solutions is mutually contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection claimed by the present invention.

[0050] The present invention provides an ion-absorbing glass product. Calculated by mole percentage, the ion-absorbing glass product comprises the following components:

[0051] SiO2: 38 mol%~55 mol%,

[0052] Al2O3: 11mol%~21mol%,

[0053] Na2O: 28 mol%~42 mol%,

[0054] B2O3: 0.9mol%~2.1mol%,

[0055] ZrO2: 0.1mol%~1.2mol%,

[0056] Bi2O3: 0mol% ~ 0.6mol%,

[0057] Among them, the components of the ion-absorbing glass product meet 0.16≤(n Al2O3 +2n B2O3 +n ZrO2 ) / (n Na2O +n SiO2 )≤0.35.

[0058] In some embodiments, the ion-absorbing glass article comprises the following components, calculated by mole percentage:

[0059] SiO2: 38 mol%~52 mol%,

[0060] Al2O3: 12mol%~18mol%,

[0061] Na2O: 30 mol%~42 mol%,

[0062] B2O3: 0.9mol%~1.5mol%,

[0063] ZrO2: 0.1mol%~0.8mol%,

[0064] Bi2O3: 0 mol% ~ 0.3 mol%.

[0065] In some embodiments, the composition of the ion-absorbing glass article satisfies 0.16≤(n Al2O3 +2n B2O3 +n ZrO2 ) / (n Na2O +n SiO2 )≤0.3.

[0066] Glass preparation typically involves chemically strengthened ion exchange processes, such as sodium-lithium and potassium-sodium ion exchange in the glass and crystalline phases. The salt bath used for ion exchange is typically composed of a specific ratio of components. During the ion exchange process, smaller alkali metal cations, such as lithium ions, continuously diffuse into the salt bath, while larger alkali metal cations in the salt bath enter the glass. However, as smaller alkali metal cations, such as lithium ions, continue to diffuse into the salt bath, the composition ratio of the salt bath changes. When the lithium ion concentration exceeds the required threshold, the ion strengthening effect can be reduced or the product dimensional expansion rate can change, which in turn affects the yield of the microglass-ceramic product.

[0067] Lithium-containing glass-ceramics with a multiphase structure, especially those with a high lithium content exceeding 20 mol%, require higher stability in the salt bath used for ion exchange than other glasses. Their chemical strengthening effect is closely related to the lithium ion content of the salt bath. Excessive or insufficient lithium ions in the salt bath can cause changes in the optimal ion exchange temperature and exchange temperature of the lithium-containing glass-ceramics, significantly impacting the ion exchange efficiency and the stability and breakage resistance of the strengthened glass-ceramics. When lithium ions from the lithium-containing glass-ceramics continuously diffuse into the salt bath, the composition ratio of the salt bath changes, and the lithium ion content exceeds the required threshold. This can easily deteriorate the ion strengthening effect of the lithium-containing glass-ceramics or cause changes in the dimensional expansion rate, thereby affecting product yield. Therefore, stabilizing the composition ratio of the ion exchange salt bath, especially the stability of the lithium ion content, can help the lithium-containing glass-ceramics achieve excellent stress distribution, thereby achieving enhanced performance based on its inherent characteristics.

[0068] The ion-absorbing glass product of the present invention has the function of absorbing lithium ions in the salt bath. During the process of ion exchange of the lithium-containing microcrystalline glass in the salt bath, it can absorb the lithium ions exchanged in the salt bath, control the balance of the lithium ion content in the salt bath, and ensure the efficiency and effect of chemical strengthening of the lithium-containing microcrystalline glass.

[0069] Among the components of the ion-absorbing glass product of the present invention:

[0070] SiO2 is a network structure former within the glass and is the main component forming the internal skeleton of the glass, providing the necessary channels for the absorption of lithium ions. In one embodiment, the SiO2 content is controlled to be 38 mol% to 55 mol% by mole percentage. For example, the SiO2 content can be any value within the range of 38 mol% to 55 mol%, such as 38 mol%, 39 mol%, 40 mol%, 41 mol%, 42 mol%, 43 mol%, 44 mol%, 45 mol%, 46 mol%, 47 mol%, 48 mol%, 49 mol%, 50 mol%, 51 mol%, 52 mol%, 53 mol%, 54 mol%, or 55 mol%.

[0071] Al2O3 can be used to enhance the strength of the glass structure. Its network structure, which is larger than the volume of silicon-oxygen tetrahedra, further provides channels for lithium ion absorption. To ensure good ion exchange efficiency of the glass-ceramics during salt bath chemical strengthening, the Al2O3 content should not be less than 11 mol% by mole. However, Al2O3 is a relatively refractory oxide, and its increased high-temperature viscosity affects molding, so the Al2O3 content must be controlled to no more than 21 mol%. In some embodiments, the Al2O3 content can be any value within the range of 11 mol% to 21 mol%, such as 11 mol%, 12 mol%, 13 mol%, 14 mol%, 15 mol%, 16 mol%, 17 mol%, 18 mol%, 19 mol%, 20 mol%, or 21 mol%.

[0072] Na2O can introduce alkali metal sodium ions, which are relatively active in the glass network structure and can migrate from the glass seed under high-temperature molten salt conditions to replace lithium ions in the salt bath. The Na2O content has a significant impact on the absorption of lithium ions in the salt bath. The higher the content, the higher the efficiency of Na-Li replacement. However, excessive Na2O can easily lead to a decrease in the chemical stability of the glass product. Taking all factors into consideration, the Na2O content is controlled to be 28 mol% to 42 mol% by mole percentage. In some embodiments, the Na2O content is any value within the range of 28 mol% to 42 mol% by mole percentage, such as 28 mol%, 29 mol%, 30 mol%, 31 mol%, 32 mol%, 33 mol%, 34 mol%, 35 mol%, 36 mol%, 37 mol%, 38 mol%, 39 mol%, 40 mol%, 41 mol%, 42 mol%, etc.

[0073] The addition of B2O3 can reduce the high-temperature melt viscosity of the glass liquid, improve the melting characteristics, and simultaneously reduce the glass transition temperature, realize high-temperature ion exchange, and improve the ion exchange rate of the glass. However, excessive addition of boron will continuously reduce the mutual diffusion coefficient of alkali metal ions, affecting the ion exchange rate of the glass. Therefore, taking all factors into consideration, the B2O3 content is controlled to be 0.9mol% to 2.1mol%. In some embodiments, calculated by molar percentage, the B2O3 content can be any content value in the range of 0.9mol% to 2.1mol%, such as 0.9mol%, 1.0mol%, 1.1mol%, 1.2mol%, 1.3mol%, 1.4mol%, 1.5mol%, 1.6mol%, 1.7mol%, 1.8mol%, 1.9mol%, 2.0mol%, 2.1mol%.

[0074] The cations in ZrO2 have a high charge, a strong electric field, and strong polarity, which can significantly improve the chemical stability of glass and reduce the stress relaxation of glass products at high temperatures. The combination of ZrO2 and Al2O3 can enhance the strengthening effect. However, ZrO2 is an extremely refractory component and easily precipitates, so it is not advisable to add too much. Taking all factors into consideration, the ZrO2 content is controlled to be 0.1 mol% to 1.2 mol% by mole. In some embodiments, the ZrO2 content is any value within the range of 0.1 mol% to 1.2 mol%, such as 0.1 mol%, 0.2 mol%, 0.3 mol%, 0.4 mol%, 0.5 mol%, 0.6 mol%, 0.7 mol%, 0.8 mol%, 0.9 mol%, 1.0 mol%, 1.1 mol%, and 1.2 mol%.

[0075] Bi2O3 can lower the melting temperature of glass materials. Calculated by molar percentage, the amount of Bi2O3 introduced is greater than or equal to 0 mol% and less than or equal to 0.6 mol%. Selecting Bi2O3 can achieve the purpose of lowering the melting temperature of glass. In some embodiments, the amount of Bi2O3 added can be 0.6 mol%, 0.5 mol%, 0.4 mol%, 0.3 mol%, 0.2 mol%, 0.1 mol%, 0.05 mol%, 0.04 mol%, 0.03 mol%, 0.01 mol%, 0 mol%, or a value not exceeding 0.6 mol%.

[0076] In addition, since the chemical strengthening process of glass is essentially a process of ion mutual diffusion, it complies with the principle of chemical reaction kinetics between glass and molten salt, and its exchange has a specific time limit. When the alkali metal ions on the surface of the glass product reach a certain concentration, a balance will be generated between the glass surface and the exchange molten salt. That is, when the chemical potential difference of the alkali metal ions in the molten salt is the same as the chemical potential difference of the alkali metal ions in the glass, mutual diffusion will no longer proceed. The ions exchanged on the glass surface reach the final concentration, and the ion ratio in the salt bath no longer changes. Therefore, in order to achieve a stable lithium ion ratio in the salt bath, the time for the ion mutual diffusion to reach equilibrium must be greater than the actual time for the microcrystalline glass to complete the ion exchange. To achieve the above purpose, the composition of the ion-absorbing glass product meets the following conditions: 0.16≤(n Al2O3 +2n B2O3 +n ZrO2 ) / (n Na2O +n SiO2 )≤0.35, for example, (n Al2O3 +2n B2O3 +n ZrO2 ) / (n Na2O +n SiO2) can be equal to any value in the range of 0.16 to 0.35, such as 0.16, 0.18, 0.20, 0.22, 0.25, 0.28, 0.29, 0.30, 0.31, 0.32, 0.33, 0.34, 0.35, etc., which is more conducive to avoiding the premature end of the absorption reaction due to an excessively fast ion exchange rate.

[0077] In some embodiments, the transition temperature Tg of the ion-absorbing glass article is ≤ 500°C, for example, Tg = 500°C, Tg = 490°C, Tg = 485°C, Tg = 455°C, Tg = 450°C, etc. These transition temperatures are lower than the ion strengthening temperature of the glass-ceramics, enabling high-temperature ion exchange, i.e., exchanging sodium ions within the ion-absorbing glass article with lithium ions in the salt bath, thereby controlling the balance of lithium ion content in the salt bath by absorbing lithium ions.

[0078] The present invention is not limited to the shape of the ion-absorbing glass product. In some embodiments, the ion-absorbing glass product may be granular and / or plate-shaped. Granular and plate-shaped ion-absorbing glass products have a large specific surface area, which can increase the contact area with the glass-ceramic strengthening salt bath, rapidly absorb lithium ions precipitated from the glass-ceramic, maintain the stability of the lithium ion content in the bath salt, and improve the efficiency and effectiveness of ion exchange between the glass-ceramic and the salt bath.

[0079] Research has found that the ion-absorbing glass products of the present invention can absorb ions to a depth (on one side) of approximately 300 μm. To achieve a relatively good absorption effect while also taking into account ease of use, in some embodiments, the particle diameter and the thickness of the glass plate are greater than 600 μm, i.e., greater than or equal to 0.6 mm. Furthermore, ion absorption is related to surface area. For equal mass, larger particles or thicker glass plates result in poorer absorption, or a greater amount of particles are used for equivalent effect. Therefore, in some embodiments, the particle size is controlled to be no larger than 2 mm.

[0080] For example, in some embodiments, when the ion-absorbing glass product is in the form of particles, its particle size is 0.6 mm to 2 mm, and can be any particle size within the range of 0.6 mm to 2 mm, such as 0.6 mm, 0.7 mm, 0.8 mm, 0.9 mm, 1.0 mm, 1.2 mm, 1.5 mm, 1.6 mm, 1.8 mm, 1.9 mm, 2.0 mm, etc. Granular ion-absorbing glass products with the above particle size ranges can also be evenly distributed around the glass-ceramics, increasing the contact area with the glass-ceramics strengthening salt bath, rapidly absorbing lithium ions precipitated from the glass-ceramics, maintaining the stability of the lithium ion content in the bath salt, and improving the efficiency and effectiveness of ion exchange between the glass-ceramics and the salt bath.

[0081] For example, in some embodiments, the ion-absorbing glass product is in the form of a plate with a thickness ranging from 0.6 mm to 2 mm, and can be any thickness within the range of 0.6 mm to 2 mm, such as 0.6 mm, 0.7 mm, 0.8 mm, 0.9 mm, 1.0 mm, 1.2 mm, 1.5 mm, 1.6 mm, 1.8 mm, 1.9 mm, or 2.0 mm. Plate-shaped ion-absorbing glass products with these thicknesses can increase the contact area with the glass-ceramic strengthening salt bath, rapidly absorbing lithium ions precipitated from the glass-ceramic, maintaining the stability of the lithium ion content in the bath salt, and improving the efficiency and effectiveness of the ion exchange between the glass-ceramic and the salt bath. Furthermore, the plate-shaped ion-absorbing glass product can be cut into irregular small pieces, which can also increase the reaction contact surface and improve the absorption rate of lithium ions exchanged from the glass-ceramic.

[0082] In some embodiments, the ion-absorbing glass article further comprises cracks on its surface. The cracks may be longitudinal or transverse, preferably so as not to interfere with subsequent cutting. Ion-absorbing glass articles having cracks can increase the specific surface area of the ion-absorbing glass article, thereby increasing the contact area for ion exchange reactions and, at the same exchange absorption equivalent, improving the rate of lithium ion absorption.

[0083] The present invention also provides a method for preparing the ion-absorbing glass product as described above. Glass raw materials are weighed according to the following composition design calculated by molar percentage:

[0084] SiO2: 38 mol%~55 mol%,

[0085] Al2O3: 11mol%~21mol%,

[0086] Na2O: 28 mol%~42 mol%,

[0087] B2O3: 0.9mol%~2.1mol%,

[0088] ZrO2: 0.1mol%~1.2mol%,

[0089] Bi2O3: 0mol% ~ 0.6mol%,

[0090] Among them, the components of the ion-absorbing glass product meet 0.16≤(n Al2O3 +2n B2O3 +n ZrO2 ) / (n Na2O +n SiO2 )≤0.35.

[0091] The weighed glass raw materials are subjected to conventional mixing and melting treatment to obtain molten glass material, which is then cooled and formed by a rapid cooling method. The internal structure and external appearance of the ion-absorbing glass product are controlled by regulating the rapid cooling rate, making it less likely to shrink, densify or fragment, thereby achieving better absorption efficiency of lithium ions.

[0092] It can be understood that rapid cooling molding refers to the cooling molding of molten glass material under conditions of rapid temperature reduction.

[0093] In some embodiments, the quenching and shaping of the molten glass material is achieved by controlling the spatial distance and spatial temperature difference between the flow channel outlet and the forming device or the water quenching tank.

[0094] When the quenching rate is less than 80°C / 8, the temperature of the molten glass material cools down slowly, and the glass structure is prone to shrinkage and densification, which is not conducive to the absorption efficiency of the subsequent ion exchange. When the quenching rate is greater than 150°C / 8, the stress inside the ion-absorbing glass product increases sharply, and the glass is prone to fragmentation, which is not conducive to subsequent applications. In some embodiments, after comprehensive consideration, the quenching rate is maintained between 80°C / 8 and 150°C / 8. For example, the quenching rate can be any quenching rate within the range of 80°C / 8 to 150°C / 8, such as 80°C / 8, 90°C / 8, 100°C / 8, 110°C / 8, 120°C / 8, 130°C / 8, 140°C / 8, and 150°C / 8. Within the above quenching rate range, fine cracks can be formed on the glass surface while preventing the internal structure of the ion-absorbing glass product from shrinking and densifying, and avoiding fragmentation caused by a sharp increase in stress due to an excessive quenching rate.

[0095] The present invention is not limited to the quench forming method, which may include at least one of leaking water quenching, water-cooled tilted roller pressing, vertical pressing, and horizontal pressing. Glass products quenched by leaking water quenching are granular. Glass products quenched by water-cooled tilted roller pressing, vertical pressing, or horizontal pressing are plate-shaped. The plate-shaped ion-absorbing glass product can be subsequently refined as needed.

[0096] The present invention also provides an ion strengthening process for lithium-containing glass-ceramics, which comprises the steps of adding the ion-absorbing glass product of the present invention as described above into a salt bath for ion strengthening of the lithium-containing glass-ceramics.

[0097] The present invention, based on the salt bath ion strengthening process well known to those skilled in the art, adds the ion-absorbing glass products of the present invention to absorb lithium ions precipitated from the microcrystalline glass, and regulates the component balance in the salt bath, thereby ensuring the chemical strengthening rate and effect of the microcrystalline glass, enabling the microcrystalline glass to obtain excellent stress distribution, and thus exerting stronger performance based on its intrinsic characteristics.

[0098] In some embodiments, the present invention mixes ion-absorbing glass products with microcrystalline glass and places them in the same container, and then enters and exits the salt bath together. The container can be a stainless steel basket. The stainless steel basket has high corrosion resistance and is not easy to precipitate ionic impurities and contaminate the microcrystalline glass strengthening salt bath.

[0099] The ion-absorbing glass products of the present invention can be used for chemical strengthening of high-lithium glass-ceramics. For example, the lithium-containing glass-ceramics contain 20 mol% or more of Li₂O, calculated on a molar basis. High-lithium glass-ceramics have a multiphase structure and require higher stability in the salt bath composition, particularly the lithium ion content.

[0100] In some embodiments, the amount of ion-absorbing glass added is 526 g / m2 based on the area of lithium-containing glass-ceramics. 2 ~960g / m 2 It can be understood that the area of lithium-containing microcrystalline glass is defined as the surface area of one side of the microcrystalline glass sheet. Setting the amount of ion-absorbing glass products introduced per square meter of microcrystalline glass can effectively regulate the absorption of lithium ions in the salt bath and avoid excessive absorption leading to an imbalance in the lithium ion content in the salt bath.

[0101] In some embodiments, the salt bath includes potassium salt, sodium salt, and lithium salt. The lithium salt is introduced into the salt bath because lithium-containing glass-ceramics, especially high-lithium glass-ceramics, have a multiphase structure. During the ion strengthening process, it is often carried out at high temperatures of 450°C to 550°C. When the ion exchange temperature approaches the lower limit, the ion exchange time will be prolonged, which can easily affect production efficiency. However, when the ion exchange temperature approaches the upper limit, the ion exchange rate will be too fast, which can easily cause the glass sheet to crack. Introducing lithium ions into the salt bath formula can inhibit the ion exchange effect and prevent the glass-ceramics from cracking.

[0102] In some embodiments, the amount of lithium salt added is 0.1%-0.3% based on the total content of potassium salt and sodium salt being 100%;

[0103] In some embodiments, based on the total content of potassium salt and sodium salt being 100%, the content of sodium salt is greater than or equal to 40% and less than 100%.

[0104] In some embodiments, ion-absorbing glass products are added to control the fluctuation of the lithium ion content in the salt bath during the chemical strengthening of glass-ceramics to be less than or equal to 60 ppm. For example, the fluctuation can be 60 ppm, 50 ppm, 40 ppm, 30 ppm, etc. By adding ion-absorbing glass products, the lithium ion content in the salt bath is controlled and the stability of the lithium ions in the salt bath is maintained, thereby improving the efficiency and effectiveness of ion exchange during chemical strengthening of glass-ceramics, especially high-lithium glass-ceramics. Larger cations replace smaller lithium ions in the glass-ceramics, generating a compressive stress distribution layer from the surface of the glass to deeper layers, effectively hindering external impact and the expansion of surface cracks, thereby increasing the durability of the glass product.

[0105] In some embodiments, the ion strengthening temperature is 500°C-550°C, and the ion strengthening time is 5 hours-7 hours. The ion exchange temperature of the glass-ceramics is closely related to the lithium ion content. The appropriate introduction of lithium ions can improve the breakage resistance of the glass sheet during ion exchange under high temperature conditions. In some embodiments, the ion strengthening temperature can be any temperature value within the range of 500-550°C, such as 500°C, 505°C, 510°C, 515°C, 520°C, 525°C, 530°C, 535°C, 540°C, 545°C, or 550°C. The ion strengthening time can be any time value within the range of 5 hours-7 hours, such as 5 hours, 5.5 hours, 6 hours, 6.5 hours, or 7 hours.

[0106] It can be understood that the above restrictions on the lithium ion content in the ion strengthening salt bath, the ion strengthening temperature and the ion strengthening time can meet only one of the conditions, or meet them all at the same time. When they are met all at the same time, it is more conducive to controlling the ion exchange rate of the microcrystalline glass to not be too slow or too fast, ensuring the stability and breakage resistance of the microcrystalline glass after strengthening, and enabling the microcrystalline glass to obtain a beneficial stress distribution, thereby exerting stronger performance based on the main characteristics.

[0107] The present invention is not limited to the composition of the glass-ceramics used in the ion-absorbing glass product. In some embodiments, the glass-ceramics include the following components, calculated by mole percentage:

[0108] SiO2: 64%~72mol%,

[0109] Li2O: 20%~25mol%

[0110] Al2O3: 2.5%~6mol%,

[0111] Na2O: 0.35%-1.5mol%,

[0112] B2O3: 0~0.45mol%

[0113] SnO2 and / or Sb2O3: 0% to 0.1 mol%,

[0114] ZrO2: 1.2%~2.4mol%,

[0115] P2O5: 0.7%~1.5mol%.

[0116] The above microcrystalline glass has a lithium ion content of more than 20 mol%, and is a microcrystalline glass with a high lithium content.

[0117] The present invention does not limit the thickness of the glass-ceramics. In some embodiments, the thickness of the glass-ceramics is 0.4 mm to 0.8 mm.

[0118] The technical solutions of the present invention are further described in detail below in conjunction with specific embodiments. It should be understood that the following specific embodiments are only used to explain the present invention and are not used to limit the present invention.

[0119] The compositions of the glass-ceramics used in the following examples and comparative examples are as follows:

[0120] SiO2: 68.55mol%,

[0121] Li2O: 20% mol%,

[0122] Al2O3: 6mol%

[0123] Na2O: 1.5 mol%

[0124] B2O3: 0.45mol%

[0125] SnO2: 0.1mol%,

[0126] ZrO2: 2.4 mol%,

[0127] P2O5: 1.0 mol%.

[0128] Examples 1 to 8

[0129] 1. Preparation of ion-absorbing glass products, refer to Figure 1

[0130] Step 1: Select the appropriate raw materials for the design of the ion-absorbing glass product components according to Table 1, weigh them according to their purity, moisture content, and ratio, and mix them evenly to obtain a meltable mixture. Place the homogeneous mixture in a glass melting furnace and melt it at a temperature range of 1000-1350°C.

[0131] Step 2: Use the rapid cooling method to shape the molten glass liquid.

[0132] In the rapid cooling forming method of Examples 1 to 6, water-cooled rollers are used to press the glass sheets, and then the glass sheets are cut into irregular small pieces with a length and width ranging from 20 to 40 mm and placed aside.

[0133] Examples 7 and 8 use the method of leaking water quenching to produce granular products.

[0134] The composition and specific process parameters of the above examples are shown in Table 1.

[0135] 2. Chemical strengthening process of glass-ceramics

[0136] The ion-absorbing glass products of Examples 1 to 8 were placed in stainless steel baskets, which were then placed around the glass-ceramic strengthened samples. To minimize the impact on production efficiency, the glass-ceramic samples were treated using a chemical salt bath that was placed in and out of the same bath as the glass-ceramic baskets. The weight of the ion-absorbing glass products added was determined by the area of the glass-ceramic sheet being placed. Specific parameters are shown in Table 2. The content of each component was measured using ICP-OES. The test results are shown in Table 2.

[0137] Comparative Examples 1 to 5

[0138] 1. Preparation of ion-absorbing glass products

[0139] Step 1: Select the appropriate raw materials for the design of the ion-absorbing glass product components according to Table 1, weigh them according to their purity, moisture content, and ratio, and mix them evenly to obtain a meltable mixture. Place the homogeneous mixture in a glass melting furnace and melt it at a temperature range of 1000-1350°C.

[0140] Step 2: The molten glass was formed using a water-cooled roller pressing and rapid cooling method. The glass sheet was then cut into irregular small pieces with a length and width ranging from 20 to 40 mm to obtain the ion-absorbing glass products of Comparative Examples 1 to 5, respectively, which were set aside for later use. Specific conditions are shown in Table 1.

[0141] 2. Chemical strengthening process of glass-ceramics

[0142] The ion-absorbing glass products of Comparative Examples 1 to 5 were chemically strengthened according to the chemical strengthening process of Example 1, as shown in Table 2.

[0143] Comparative Example 6 refers to the chemical strengthening process of Example 3, but the difference is that the ion-absorbing glass product of the present invention is not added in Comparative Example 6. See Table 2 for details.

[0144] Comparative Example 7 selects the ion-absorbing glass product prepared in Example 4 and refers to the chemical strengthening process of Example 4, but the difference is that Comparative Example 7 does not add micro-ceramic glass, see Table 2 for details.

[0145] Comparative Example 8 selected the ion-absorbing glass product prepared in Example 3 and referred to the chemical strengthening process of Example 3, except that the addition amount of the ion-absorbing glass product in Comparative Example 8 was halved from 626 g to 313 g, as shown in Table 2.

[0146] Comparative Example 9 selected the ion-absorbing glass product prepared in Example 5 and referred to the chemical strengthening process of Example 5, except that the weight of the ion-absorbing glass product in Comparative Example 9 was increased from 982 g to 1248 g, as shown in Table 2.

[0147] Comparative Examples 10 to 12

[0148] Comparative Examples 10 to 12 selected the ion-absorbing glass products prepared in Example 1 and followed the chemical strengthening process of Example 1, except that the salt bath conditions in Comparative Examples 10 to 12 were different, as shown in Table 2.

[0149] Table 1 Composition and preparation process parameters of ion-absorbing glass products of Examples 1 to 8 and Comparative Examples 1 to 5

[0150]

[0151]

[0152] Table 2 Chemically enhanced ion exchange process conditions and ion exchange effects

[0153]

[0154] Performance Testing

[0155] The glass-ceramic samples in the embodiment and the comparative example were placed in a muffle furnace for rapid cooling after the ion exchange was completed; the residue on the surface of the glass-ceramic was cleaned with hot water, and then tested with an SLP-2000 surface stress meter. The parameter results are shown in Table 3.

[0156] Table 3 Glass-ceramic strengthening results of Examples and Comparative Examples

[0157] Serial number CS mean / MPa DOL mean value / μm Product surface condition Example 1 225 118 normal Example 2 230 125 normal Example 3 235 121 normal Example 4 221 118 normal Example 5 217 109 normal Example 6 220 105 normal Example 7 226 111 normal Example 8 242 119 normal Comparative Example 1 / / / Comparative Example 2 / / / Comparative Example 3 192 100 normal Comparative Example 4 187 89 normal Comparative Example 5 194 96 normal Comparative Example 6 196 102 normal Comparative Example 7 / / / Comparative Example 8 201 106 normal Comparative Example 9 232 116 Some fragments Comparative Example 10 235 120 Severe fragmentation Comparative Example 11 211 107 normal Comparative Example 12 165 82 normal

[0158] As can be seen from Table 2, according to the ion-absorbing glass products and application methods proposed in the present invention, after the ion exchange is completed, the lithium ion content in the salt bath fluctuates by only 20 ppm or less. Converted into lithium salt, it can be found that its content is not significantly different from the ratio before chemical strengthening.

[0159] Combining Table 2 and Table 3, we can see that:

[0160] In Comparative Examples 1 and 2 relative to Example 1, the molding cooling rate was greater than 150° C. / 8, and the glass plate products were severely cracked and could not be molded.

[0161] Comparative Example 3, compared to Example 1, uses a molding cooling rate of <80°C / 8. The product is slow annealed, resulting in a thickness >2mm and fewer surface cracks. Using the same number of glass-ceramics sheets and the same ion exchange process conditions as Example 1, the lithium ion content in the salt bath significantly increased after ion exchange. This indicates that reducing the cooling rate affects the absorption efficiency of glass products. The increased lithium ion content in the salt bath has an impact on the strengthening properties of the glass-ceramics sheets. As shown in Table 3, the average CS and DOL values of the glass-ceramics in Comparative Example 3 are lower than those in Example 1.

[0162] Compared to Example 1, the ion-absorbing glass products in Comparative Examples 4 and 5 do not fall within the scope of protection of the present invention, and their glass transition temperatures are greater than 500°C. Using the same preparation conditions as Example 1, the same number of glass-ceramics sheets, and the same ion exchange process conditions, the lithium ion content in the salt bath after ion exchange was significantly higher than that of Example 1. The average CS and DOL values of these glass-ceramics were significantly lower than those of the glass-ceramics in Example 1.

[0163] Comparing Comparative Example 6 with Example 3, while Comparative Example 6 lacks the ion-absorbing glass product of the present invention, with the same number of glass-ceramics sheets and the same ion exchange process conditions, the lithium ion content in the salt bath significantly increases after ion exchange, even doubling when converted into lithium salt. The increasing lithium ion content in the salt bath affects the strengthening properties of the glass-ceramics. As shown in Table 3, the average CS and DOL values of the glass-ceramics in Comparative Example 6 are lower than those in Example 3.

[0164] Comparing Comparative Example 7 with Example 4, where no glass-ceramic sheet was placed, using the same ion-absorbing glass product with the same ratio and the same ion exchange process conditions, the ion-absorbing glass product primarily absorbed the lithium ions already present in the salt bath, as the glass-ceramic sheet did not diffuse lithium ions into the salt bath. As shown in Table 3, the lithium ion content in the salt bath was significantly reduced after the ion exchange, and when converted into lithium salt, the content was reduced by half. This demonstrates that the ion-absorbing glass product of the present invention exhibits excellent lithium ion absorption.

[0165] Comparing Comparative Example 8 with Example 3, the addition amount of the ion-absorbing glass product in Comparative Example 8 was halved from 626g to 313g. Using the same number of glass-ceramics and the same ion exchange process conditions, the lithium ion content in the salt bath after ion exchange significantly increased compared to Example 3, weakening the absorption efficiency of the ion-absorbing glass product. When converted to lithium salt, the content fluctuated significantly, primarily due to an increase in lithium content. The average CS and DOL values of the glass-ceramics in Comparative Example 3 were also significantly lower than those in Example 3.

[0166] Comparing Comparative Example 9 with Example 5, the ion-absorbing glass product in Comparative Example 9 increased from 982g to 1248g. Using the same number of glass-ceramics sheets and the same ion exchange process conditions, the lithium ion content in the salt bath after ion exchange was significantly reduced compared to Example 5, and even lower than the initial lithium ion content. This demonstrates the enhanced absorption efficiency of the ion-absorbing glass product, absorbing the lithium ions originally introduced into the salt bath. After conversion to lithium salt, the content fluctuated significantly, primarily manifesting as a decrease in lithium content. The decreasing lithium ion content in the salt bath, at a temperature of 530°C, caused some cracking of the glass-ceramics in Comparative Example 9.

[0167] Comparative Examples 10 to 12 employed different salt bath conditions relative to Example 1. Specifically, no lithium salt was added in Comparative Example 10; in Comparative Example 11, the sodium salt content was <40%; and in Comparative Example 12, the sodium salt content was <40% and >0.3% lithium salt was added. Using the ion-absorbing glass products prepared in Example 1, under the same ion exchange process conditions, after ion exchange, the glass-ceramic sample in Comparative Example 10 exhibited severe fragmentation, while the lithium content in Comparative Example 11 fluctuated less, but the average CS and DOL values of the glass-ceramic were lower than those of the glass-ceramic in Example 1. The lithium content in Comparative Example 12 fluctuated significantly, and the average CS and DOL values of the glass-ceramic were significantly lower than those of the glass-ceramic in Example 1.

[0168] It should be noted that the microcrystalline glass used in the above embodiments and comparative examples is only one example listed, which is only used to verify the effect of the ion-absorbing glass products of the present invention on the chemical strengthening of microcrystalline glass, and does not constitute a limitation on the application of the ion-absorbing glass products of the present invention in the type of microcrystalline glass.

[0169] The above are only preferred embodiments of the present invention and are not intended to limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made using the contents of the present invention description and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. An ion-absorbing glass product, characterized in that: Calculated by mole percentage, the components of the ion-absorbing glass product are as follows: SiO2: 38mol%~55mol%, Al2O3: 11mol%~21mol%, Na2O: 28mol%~42mol%, B2O3: 0.9mol%~2.1mol%, ZrO2: 0.1mol%~1.2mol%, Bi2O3: 0.01mol%~0.6mol%, Wherein, the components of the ion-absorbing glass product satisfy 0.16≤(n Al2O3 +2n B2O3 +n ZrO2 ) / (n Na2O +n SiO2 ) ≤0.35; The transition point temperature Tg of the ion-absorbing glass product is ≤500°C.

2. The ion-absorbing glass product according to claim 1, wherein Calculated by mole percentage, the ion-absorbing glass product includes the following components: SiO2: 38mol%~52mol%, Al2O3: 12mol%~18mol%, Na2O: 30mol%~42mol%, B2O3: 0.9mol%~1.5mol%, ZrO2: 0.1mol%~0.8mol%, Bi2O3: 0.01mol%~0.3 mol%.

3. The ion-absorbing glass product according to claim 1, wherein The components of the ion-absorbing glass product satisfy 0.16≤(n Al2O3 +2n B2O3 +n ZrO2 ) / (n Na2O +n SiO2 ) ≤0.

3.

4. The ion-absorbing glass product according to claim 1, wherein The ion-absorbing glass product is in the shape of particles and / or plates.

5. The ion-absorbing glass product according to claim 1, wherein The ion-absorbing glass product has cracks on its surface.

6. The ion-absorbing glass product according to claim 1, wherein The ion-absorbing glass product is in the shape of particles, and the particle size of the ion-absorbing glass product is 0.6 mm to 2 mm; And / or, the ion-absorbing glass product is in a plate shape, and the thickness of the plate-shaped ion-absorbing glass product is 0.6 mm to 2 mm.

7. A method for preparing the ion-absorbing glass product according to any one of claims 1 to 6, characterized in that: The following steps are involved: The ion-absorbing glass product is obtained by cooling and shaping the molten glass material through a rapid cooling forming method.

8. The method for preparing the ion-absorbing glass product according to claim 7, characterized in that: The cooling rate of the rapid cooling forming is 80°C / s-150°C / s.

9. The method for preparing the ion-absorbing glass product according to claim 7, characterized in that: The rapid cold forming method includes at least one of leaking water quenching, water-cooled inclined roller pressing, vertical pressing and horizontal pressing.

10. An ion strengthening process for lithium-containing glass-ceramics, characterized in that: The following steps are involved: The ion-absorbing glass product according to any one of claims 1 to 6 is added to a salt bath for ion strengthening of the lithium-containing glass-ceramics.

11. The ion strengthening process for lithium-containing glass-ceramics according to claim 10, characterized in that: Calculated by mole percentage, the lithium-containing glass-ceramics contains more than 20 mol% of Li2O.

12. The ion strengthening process for lithium-containing glass-ceramics according to claim 10, characterized in that: Based on the area of the lithium-containing glass-ceramics, the amount of the ion-absorbing glass product added is 526 g / m 2 ~960 g / m 2 .

13. The ion strengthening process for lithium-containing glass-ceramics according to claim 10, characterized in that: The ion-absorbing glass product and the lithium-containing glass-ceramics enter and exit the salt bath together.

14. The ion strengthening process for lithium-containing glass-ceramics according to claim 10, characterized in that: The salt bath formulation includes potassium salt, sodium salt and lithium salt.

15. The ion strengthening process for lithium-containing glass-ceramics according to claim 14, characterized in that: Based on 100wt% of the total content of the potassium salt and the sodium salt, the amount of the lithium salt added is 0.1wt%-0.3wt%; And / or, based on 100 wt % of the total content of the potassium salt and the sodium salt, the content of the sodium salt is greater than or equal to 40 wt % and less than 100 wt %.

16. The ion strengthening process for lithium-containing glass-ceramics according to claim 10, characterized in that: During the ion strengthening process of the lithium-containing glass-ceramics, the fluctuation value of the lithium ion content in the salt bath is less than or equal to 60 ppm.

17. The ion strengthening process for lithium-containing glass-ceramics according to claim 10, characterized in that: The ion strengthening temperature of the lithium-containing glass-ceramics is 500° C.-550° C.; And / or, the ion strengthening time of the lithium-containing microcrystalline glass is 5h-7h.

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