TWI677481B - Glass composition for chemically strengthened alkali-aluminoborosilicate glass with low dielectric constant - Google Patents

Abstract

A glass composition for manufacturing a chemically strengthened alkali boroaluminosilicate glass with a low dielectric constant, and a method for manufacturing a chemically strengthened alkali boroaluminosilicate glass with a low dielectric constant. The chemically strengthened alkali boroaluminosilicate glass is suitable for high-strength cover glass for solar panels, solar cell cover glass, and laminated safety glass. The low dielectric constant of glass improves sensitivity, response time, power consumption, and accuracy.

Description

Glass composition with low dielectric constant chemically strengthened alkali aluminum borosilicate glass

The invention relates to a glass composition for chemically strengthened alkali aluminoborosilicate glass with low dielectric constant, and a method for manufacturing chemically strengthened alkali aluminosilicate glass with low dielectric constant, and Application and application of dielectric constant chemically strengthened alkali aluminosilicate glass.

Chemically strengthened glass is generally significantly stronger than annealed glass due to the glass composition and the chemical strengthening process used to make the glass. This chemical strengthening process can be used to strengthen glass of all sizes and shapes without optical distortion, which enables the production of thin, small, and complex glass samples that cannot be thermally tempered. These properties have made chemically strengthened glass (more specifically, chemically strengthened alkali-aluminosilicate glass) a popular and widely used device for consumer mobile electronic devices such as smartphones, tablets, and notepads. select.

Chemical strengthening processes generally include ion exchange processes. In this ion exchange process, the glass is placed in a molten salt. The molten salt contains ions with a larger ion radius than the ions present in the glass, so that the smaller ions present in the glass will be drawn from the heated solution. Larger ion substitution. In general, potassium ions in the molten salt will replace the smaller sodium ions present in the glass. This replacement of smaller sodium ions in the glass by larger potassium ions in the heating solution will result in the formation of a compressive stress layer on both sides of the glass and a central tension sandwiched between the compressive stress layers Area. The tensile stress in the central tension zone (CT, generally expressed in millions of Pascals (MPa)) is the compressive stress of the compressive stress layer (CS, also generally expressed in million Pascals) and the depth of the compressive stress layer expressed by the following equation (DOL) related: CT = CS × DOL / (t-2DOL) where t is the thickness of the glass.

In order to be used as a touch display cover glass, it is necessary to increase the resistance of the glass to scratches and impact damage. This can be achieved by increasing the depth of the compressive stress and compressive stress layers. However, in order to keep the tensile stress in the central stress region within an acceptable range, an increase in both the compressive stress and the thickness of the compressive stress layer adversely results in an increase in the thickness of the glass.

At the same time, it is desirable that the cover glass be as thin as possible. However, as the tensile stress in the central tension region increases with decreasing glass thickness, it is difficult to maintain an acceptable tensile stress in the central tension region while maintaining high compressive stress and high compressive stress layer depth. In these examples, it is generally necessary to make the compressive stress to layer depth ratio (CS / DOL) as high as possible.

In addition, the dielectric constant of glass affects the sensitivity, response time, power consumption rate, and analog signal misjudgment rate of touch devices, resulting in slow response. In general, the lower the dielectric constant, the better the sensitivity, response time, power consumption rate, and accuracy.

The dielectric constant of currently commercially available chemically strengthened alkali aluminosilicate glass is between 7.1 and 7.8 (measured at a frequency of 1 MHz). Compared with non-alkali aluminosilicate glass (such as thin-film transistor liquid crystal display glass (TFT-LCD glass)), the proportion of glass-forming materials is relatively low, while the proportion of ionic compounds having conductivity is relatively high. Generally, TFT-LCD glass is a non-alkaline aluminum borosilicate glass with a dielectric constant of about 5.2 to about 6.0.

The lower the dielectric constant of the glass substrate material used in a touch display, the higher the sensitivity. When developing glass components with low dielectric constants, both mechanical and physical properties that provide chemical strength should be maintained. Therefore, there is a need for a glass having high strength and low dielectric constant.

In several exemplary embodiments, the present invention provides an ion-exchangeable glass composition for manufacturing chemically strengthened alkali aluminum borosilicate glass with low dielectric constant and high strength. According to several exemplary embodiments, the composition has a high boron oxide content and good melting properties, which enables the glass sheet to be formed in an overflow down-draw process. According to several exemplary embodiments, the composition has a high content of sodium oxide, which makes the composition suitable for an ion exchange process. According to several exemplary embodiments, an easy-to-melt silica-alumina-sodium oxide glass is provided.

By increasing the amount of the glass-forming material, the dielectric constant of the glass is effectively improved. For oxide glass, the glass-forming materials are mainly silicon dioxide, boron oxide, phosphorus oxide, and beryllium oxide. Beryllium oxide is toxic and has been discarded from consumer electronics. Phosphorous oxides are not suitable for use in overflow down draw processes because they can cause corrosion damage to precious metal equipment. Generally speaking, the boron oxide in the TFT-LCD glass substrate can reach 6 to 11 weight percent. However, currently boron oxide is rarely used or is controlled to be less than 2 weight percent in chemically strengthened cover glass.

The invention provides a chemically strengthened alkali aluminum borosilicate glass composition having a low dielectric constant and an increased boron oxide content. In several exemplary embodiments, the dielectric constant is lower than about 6.0, which is lower than the dielectric constant of aluminosilicate glass of currently commercially available touch displays. The dielectric constant of glass can be reduced by increasing the content of silicon dioxide and boron oxide in the glass and reducing the proportion of conductive ionic compounds such as sodium oxide, potassium oxide, magnesium oxide, and calcium oxide.

The ratio of different glass compositions will affect the properties of the glass. In order to ensure that the glass composition is suitable for forming glass by the overflow down-draw process, chemical strengthening can be performed by ion exchange through the overflow down-draw process, and it has high strength after ion exchange, and appropriate proportions of alumina and oxygen must be added Sodium. To ensure the glass has a low melting temperature and workability, an appropriate amount of magnesium oxide may be added. Compared to increasing the ratio of metal oxides (such as calcium oxide, potassium oxide, and zinc oxide), increasing magnesium oxide is a good choice because it reduces the specific gravity of the glass and increases the strength of the glass.

In several exemplary embodiments, the ion-exchangeable glass composition for manufacturing a chemically strengthened alkali aluminum borosilicate glass with a low dielectric constant comprises: about 60.0 to about 70.0 mole percent (mol%) of two Silicon oxide (SiO ₂ ); about 6.0 to about 10.0 mol% of aluminum oxide (Al ₂ O ₃ ); about 5.0 to about 10.0 mol% of sodium oxide (Na ₂ O); about 15.0 to about 25.0 mol% of Boron trioxide (B ₂ O ₃ ); about 0 to about 5.0 mol% potassium oxide (K ₂ O); and about 0 to about 3.0 mol% magnesium oxide (MgO).

According to several exemplary embodiments, the ion-exchangeable glass composition for manufacturing a chemically strengthened alkali aluminum borosilicate glass with a low dielectric constant includes about 60.0 to about 70.0 mol% of silicon dioxide (SiO ₂ ). Silicon dioxide is the largest single component in alkali aluminosilicate glass, and together with boron trioxide forms the matrix of the glass. Silicon dioxide also acts as a structural coordinator for glass and contributes to the formability, rigidity and chemical resistance of glass. When the concentration is higher than 70.0 mol%, the silicon dioxide increases the melting point temperature of the glass composition, so that the molten glass becomes very difficult to handle, resulting in difficulty in forming the glass. When the concentration is lower than 60.0 mol%, the silicon dioxide will unfavorably tend to substantially increase the liquidus temperature of the glass, especially in a glass composition having a high concentration of sodium oxide or magnesium oxide, and will tend to Causes glass to devitrify.

According to several exemplary embodiments, the ion-exchangeable glass composition for manufacturing a chemically strengthened alkali aluminum borosilicate glass with a low dielectric constant includes about 6.0 to about 10.0 mol% of alumina (Al ₂ O ₃ ). . When the concentration is between about 6.0 to about 10.0 mol%, alumina increases the strength of the alkali aluminosilicate glass and promotes ion exchange between sodium ions in the glass and potassium ions in the molten salt. As the alumina content increases, the dielectric constant increases with the ring structure of the glass network. The amount of alumina in the glass represents a compromise between glass properties such as dielectric constant, ion exchange depth, and glass strength.

According to several exemplary embodiments, the ion-exchangeable glass composition for manufacturing a chemically strengthened alkali aluminum borosilicate glass with a low dielectric constant includes about 5.0 to about 10.0 mol% of sodium oxide (Na ₂ O). Alkali metal oxides are used as auxiliary agents to achieve low liquidus temperature and low melting point. In the case of sodium oxide, Na ₂ O is used for successful ion exchange. In order to perform sufficient ion exchange to produce substantially improved glass strength, sodium oxide is included in the composition at the above-mentioned concentration. Meanwhile, in order to increase the probability of ion exchange between sodium ions and potassium ions, according to several exemplary embodiments, the ion exchangeable glass composition for manufacturing a chemically strengthened alkali aluminum borosilicate glass with a low dielectric constant includes: Has potassium oxide (K ₂ O) between about 0 to about 5.0 mol%.

According to several exemplary embodiments, the ion-exchangeable glass composition for manufacturing a chemically strengthened alkali aluminum borosilicate glass with a low dielectric constant includes about 15.0 to about 25.0 mol% of boron trioxide (B ₂ O ₃ ). Boron trioxide is used as a fluxing agent and a glass coordinator. At the same time, both the glass melting temperature and the dielectric constant tend to decrease as the concentration of boron trioxide increases. The direction of ion exchange between sodium and potassium ions will be adversely affected by the increase in the concentration of boron trioxide. Therefore, as the concentration of boron trioxide increases, there is a trade-off between the dielectric constant of the glass and the ion exchange capacity of the glass.

According to several exemplary embodiments, the ion-exchangeable glass composition for manufacturing a chemically strengthened alkali aluminum borosilicate glass with a low dielectric constant includes about 0 to about 3.0 mol% of magnesium oxide (MgO). In several exemplary embodiments, the ion-exchangeable glass composition for manufacturing a chemically strengthened alkali aluminoborosilicate glass with a low dielectric constant includes about 1.0 to about 2.0 mol% of magnesium oxide. Compared with other basic oxides such as calcium oxide (CaO), strontium oxide (SrO), and barium oxide (BaO), magnesium oxide is also believed to increase the strength of glass and reduce the specific gravity of glass.

According to the above-mentioned several exemplary embodiments of the ion-exchangeable glass composition for manufacturing a chemically strengthened alkali aluminum borosilicate glass with a low dielectric constant, the glass has a liquidus temperature of at least about 750 ° C (at this temperature) Crystals were observed first). According to several exemplary embodiments of the above-mentioned ion-exchangeable glass composition for manufacturing a chemically strengthened alkali aluminum borosilicate glass with a low dielectric constant, the glass has a liquidus temperature of at least about 800 ° C. According to several exemplary embodiments of the above-mentioned ion-exchangeable glass composition for manufacturing a chemically strengthened alkali aluminum borosilicate glass with a low dielectric constant, the glass has a liquidus temperature of at least about 850 ° C. According to the above-mentioned several exemplary embodiments of the ion-exchangeable glass composition for manufacturing a chemically strengthened alkali aluminum borosilicate glass with a low dielectric constant, the glass has a liquidus temperature of at least about 900 ° C. According to several exemplary embodiments of the above-mentioned ion-exchangeable glass composition for manufacturing a chemically strengthened alkali aluminum borosilicate glass with a low dielectric constant, the glass has a liquidus temperature of about 750 ° C to about 900 ° C.

According to several exemplary embodiments, the present invention provides a method for manufacturing a chemically strengthened alkali aluminum borosilicate glass with a low dielectric constant. According to several exemplary embodiments, the method includes: mixing and melting ingredients to form a homogeneous glass melt, which includes: forming the glass using a method selected from the overflow down-draw method, the float method, and a combination thereof; annealing the glass ; And chemically strengthening the glass by ion exchange.

According to several illustrative embodiments, the manufacture of chemically strengthened alkali-aluminum-borosilicate glass with low dielectric constant can be implemented using a traditional overflow down-draw method, which is familiar to those skilled in the art and generally Includes direct or indirect heating of precious metal systems, consisting of a homogenizing device, a device (clarifier) that reduces the foam content by clarification, a cooling and thermal homogenizing device, a dispersing device, and other devices. In the traditional way, the float process involves floating molten glass on a bed of molten metal (typically tin), which results in a glass that is very flat and has a uniform thickness.

According to several exemplary embodiments of the method for manufacturing a chemically strengthened alkali aluminoborosilicate glass with a low dielectric constant as described above, the ion-exchangeable glass composition is melted at about 450 ° C. for about 8 hours. According to several exemplary embodiments of the method for manufacturing a chemically strengthened alkali aluminoborosilicate glass with a low dielectric constant as described above, the ion-exchangeable glass composition is melted at about 450 ° C. for about 16 hours. According to several exemplary embodiments of the method for manufacturing a chemically strengthened alkali aluminoborosilicate glass with a low dielectric constant as described above, the ion-exchangeable glass composition is melted at about 450 ° C. for about 24 hours.

According to several exemplary embodiments of the method for manufacturing a chemically strengthened alkali-aluminum-borosilicate glass with a low dielectric constant as described above, the ion-exchangeable glass composition is annealed at a rate of about 0.5 ° C./hour until It reaches room temperature (or about 21 ° C).

According to several exemplary embodiments, the above-mentioned ion-exchangeable glass composition for manufacturing a chemically strengthened alkali aluminum borosilicate glass with a low dielectric constant is chemically strengthened according to traditional ion exchange conditions. According to several exemplary embodiments of the method for manufacturing a chemically strengthened alkali-aluminum-borosilicate glass with a low dielectric constant described above, the ion exchange process takes place in a molten salt bath. In several exemplary embodiments, the molten salt is potassium nitrate (KNO ₃ ).

According to several exemplary embodiments of the method for manufacturing a chemically strengthened alkali aluminoborosilicate glass with a low dielectric constant as described above, the ion exchange treatment occurs at a temperature range of about 390 ° C to about 450 ° C. According to several illustrative embodiments of the method for manufacturing a chemically strengthened alkali-aluminum-borosilicate glass with a low dielectric constant as described above, the ion exchange treatment occurs at a temperature of about 450 ° C. According to several illustrative embodiments of the method for manufacturing a chemically strengthened alkali-aluminum-borosilicate glass with a low dielectric constant as described above, the ion exchange treatment occurs at a temperature of at least about 450 ° C. According to several exemplary embodiments of the method for manufacturing a chemically strengthened alkali aluminum borosilicate glass with a low dielectric constant as described above, the ion exchange treatment occurs at a temperature of about 450 ° C.

According to the above, it is used for manufacturing chemically strengthened alkali aluminum borosilicate glass with low dielectric constant. Several exemplary embodiments of the method, the ion exchange treatment is performed for about 4 hours. According to several exemplary embodiments of the method for manufacturing a chemically strengthened alkali-aluminum-borosilicate glass with a low dielectric constant as described above, the ion exchange treatment is performed for about 8 hours. According to several illustrative embodiments of the method for manufacturing a chemically strengthened alkali-aluminum-borosilicate glass with a low dielectric constant as described above, the ion exchange treatment is performed for about 16 hours. According to several illustrative embodiments of the method for manufacturing a chemically strengthened alkali-aluminum-borosilicate glass with a low dielectric constant as described above, the ion exchange treatment is performed for about 24 hours.

According to the above-mentioned several exemplary embodiments of the chemically strengthened alkali aluminum borosilicate glass with low dielectric constant, the glass has a surface compressive stress layer having a compressive stress of at least about 100 MPa. According to the above-mentioned several exemplary embodiments of the chemically strengthened alkali aluminum borosilicate glass with low dielectric constant, the glass has a surface compressive stress layer having a compressive stress of at least about 150 MPa. According to the above-mentioned several exemplary embodiments of the chemically strengthened alkali aluminum borosilicate glass with low dielectric constant, the glass has a surface compressive stress layer having a compressive stress of at least about 200 MPa. According to the above-mentioned several exemplary embodiments of the chemically strengthened alkali aluminum borosilicate glass with low dielectric constant, the glass has a surface compressive stress layer having a compressive stress of at least about 250 MPa. According to the above-mentioned several exemplary embodiments of the chemically strengthened alkali aluminum borosilicate glass with low dielectric constant, the glass has a surface compressive stress layer having a compressive stress between about 100 MPa and about 250 MPa. According to the above-mentioned several exemplary embodiments of the low-k chemically strengthened alkali-aluminum-borosilicate glass, the glass has a surface compressive stress layer having a compressive stress between about 140 MPa and about 260 MPa. According to the above-mentioned several exemplary embodiments of the chemically strengthened alkali-aluminum-borosilicate glass with low dielectric constant, the glass has a surface compressive stress layer having a compressive stress between about 150 MPa and about 250 MPa. According to the above-mentioned several exemplary embodiments of the chemically strengthened alkali aluminum borosilicate glass with low dielectric constant, the glass has a surface compressive stress layer having a compressive stress of about 160 MPa to about 240 MPa.

According to the above-mentioned several exemplary embodiments of the low-k chemically strengthened alkali aluminum borosilicate glass, the glass has a surface compressive stress layer having a depth of at least about 16.0 μm. According to the above-mentioned several exemplary embodiments of the chemically strengthened alkali aluminum borosilicate glass with low dielectric constant, the glass has a surface compressive stress layer having a depth of at least about 17.0 μm. According to the above-mentioned several exemplary embodiments of the low-k chemically strengthened alkali-aluminum-borosilicate glass, the glass has a surface compressive stress layer having a depth of at least about 20.0 μm. According to the above-mentioned several exemplary embodiments of the chemically strengthened alkali aluminum borosilicate glass with low dielectric constant, the glass has a surface compressive stress layer having a depth of at least about 27.0 μm. According to the above-mentioned several exemplary embodiments of the chemically strengthened alkali aluminum borosilicate glass with low dielectric constant, the glass has a surface compressive stress layer having a depth of between about 15.0 μm and about 35.0 μm. According to the above-mentioned several exemplary embodiments of the chemically strengthened alkali-aluminum-borosilicate glass with low dielectric constant, the glass has a surface compressive stress layer having a depth between about 17.0 μm and about 28.0 μm. According to the above-mentioned several exemplary embodiments of the chemically strengthened alkali-aluminum-borosilicate glass with low dielectric constant, the glass has a surface compressive stress layer having a depth between about 20.0 μm and about 30.0 μm.

According to the above-mentioned several exemplary embodiments of the chemically strengthened alkali-aluminum-borosilicate glass with low dielectric constant, the glass has a dielectric constant (at 25 ° C, 1 MHz, 5 V) of about 5.0 to about 6.5. According to several exemplary embodiments of the above-mentioned chemically strengthened alkali-aluminum-borosilicate glass with low dielectric constant, the glass has a dielectric constant (at 25 ° C, 1 MHz, 5 V) of about 5.3 to about 6.0. According to the above-mentioned several exemplary embodiments of the chemically strengthened alkali aluminum borosilicate glass with low dielectric constant, the glass has a dielectric constant of less than 6.0 (at 25 ° C., 1 MHz, 5 V).

According to the above-mentioned several exemplary embodiments of the chemically strengthened alkali-aluminum-borosilicate glass with low dielectric constant, the glass has a density of about 2.29 g / cm ³ and a linear expansion coefficient α _{25 of} about 53.0 to about 70.0. _-300 10 ^-7 / ° C. According to the above-mentioned several exemplary embodiments of the chemically strengthened alkali-aluminum-borosilicate glass with low dielectric constant, the glass has a density of less than about 2.3 g / cm ³ .

According to the above-mentioned several exemplary embodiments of the chemically strengthened alkali aluminum borosilicate glass with low dielectric constant, the glass is subjected to ion exchange treatment at a temperature between about 390 ° C and about 450 ° C for about 2 hours to about 8 hours and chemically strengthened, and the glass has: (1) a surface compressive stress layer having a compressive stress of at least about 150 MPa, and a depth of the surface compressive stress layer being at least about 17.0 μm, and (2) a dielectric constant below 6.0 . According to the above-mentioned several exemplary embodiments of the chemically strengthened alkali aluminum borosilicate glass with low dielectric constant, the glass is chemically strengthened by performing ion exchange treatment at a temperature of about 450 ° C. for about 8 hours, and the glass is It has: (1) a surface compressive stress layer having a compressive stress between about 150 MPa and about 250 MPa, and the depth of the surface compressive stress layer is between about 17.0 μm and about 28.0 μm, and (2) between about 5.3 and about 6.0 Dielectric constant.

According to the above-mentioned several exemplary embodiments of the chemically strengthened alkali aluminum borosilicate glass with low dielectric constant, the glass can be used as a protective glass in application devices such as solar panels, refrigerator doors, and other home appliances. According to the above-mentioned several exemplary embodiments of the chemically strengthened alkali aluminum borosilicate glass with low dielectric constant, the glass can be used as a protective glass for a television, a safety glass for an automatic teller machine, and other electronic products. According to several exemplary embodiments of the above-mentioned low-k chemically strengthened alkali-aluminum-borosilicate glass, the glass can be used as a cover glass for consumer electronic devices such as smart phones, tablets, and notebooks. The glass can also be used in applications such as vehicle windshields and building smart windows as a substrate. According to the above-mentioned several exemplary embodiments of the chemically strengthened alkali aluminum borosilicate glass with low dielectric constant, the glass can be used as a touch screen or a touch panel due to its high strength.

The following examples serve as illustrative examples of the above composition and method.

An ion-exchangeable glass composition was prepared as follows, which included the ingredients shown in Table 1 below:

The batch materials shown in Table 2 were weighed and mixed before being added to a 2-liter plastic container. The batch materials used are of chemical reagent grade quality.

The particle size of sandstone is between 0.045 and 0.25mm. A roller is used to mix the raw materials to produce a homogeneous batch and break up the soft viscous polymer. The mixed batch was transferred from a plastic container to an 800 ml platinum-rhodium alloy crucible for glass melting. The platinum-rhodium crucible was placed on an alumina support and loaded into a high-temperature furnace equipped with a MoSi heating element, which operated at a temperature of 900 ° C. The furnace temperature was gradually increased to 1620 ° C, and the platinum-rhodium crucible and its supporting system were held at this temperature 4 hour. The molten bath material was then poured from a platinum-rhodium crucible onto a stainless steel plate to form a glass cake. While the glass cake was still hot, it was transferred to an annealer, held at 500 ° C for 2 hours, and then cooled to 430 ° C at a rate of 0.5 ° C / min. After that, the sample was naturally cooled to room temperature (21 ° C).

The glass sample is then chemically strengthened by placing it in a molten salt bath, where the sodium ion in the glass is exchanged with externally supplied potassium ions at 450 ° C (which is lower than the strain point of the glass) for 8 hours. . In this way, the glass sample is strengthened by ion exchange to produce a compressive stress layer at the treated surface.

The measurement of the compressive stress at the glass surface and the depth of the compressive stress layer (based on double refraction) are determined by observing the cross section of the glass with a polarizing microscope (Bayesian complementary device). The compressive stress on the glass surface is the measured birefringence (nm * cm / N) from an assumed stress-optical constant of 0.30 (Scholze, H., Nature, Structure and Properties, Springer-Verlag, 1988, p. 260) Calculated.

The results of the composition shown in Table 1 above are described in the field "Ex.1" in Table 3 below. The other compositions shown in the columns "Ex.2" to "Ex.10" in Table 3 were prepared in a similar manner to the composition shown in the above Ex.1.

The definitions of the symbols proposed in Table 3 are as follows: ‧ d : density (g / ml), which is measured by the Archimedes method (ASTM C693); ‧ n _D : refractive index, which is measured by a refractometer; ‧Α: Thermal expansion coefficient (CTE), which is the change in the linear direction from 50 to 300 ° C, measured by the expansion method; ‧T _melting : The melting temperature at a viscosity of 10 ² poise, from a high temperature cylinder Measured by a viscometer; ‧T _working : The operating temperature of the glass at a viscosity of 10 ⁴ poise, measured by a high-temperature cylindrical viscometer; ‧T _liquidus : the temperature of the liquid phase, which changes gradually at this temperature The first crystallization was observed in the hull of a temperature heating furnace (ASTM C829-81). The general test of crystallization was performed for 24 hours; ‧T _soften : the glass softening temperature at a viscosity of 10 ^7.6 poise, Measured by fiber lengthening method; ‧T _annealing : glass annealing temperature at a viscosity of 10 ¹³ poise, measured by fiber lengthening method; ‧T _strain : glass strain temperature at a viscosity of 10 ^14.5 poise , Measured by fiber lengthening method; ‧k: dielectric constant, measured at 25 ° C, 1MHz and 5V, with SJ / T 110 Measured at 43-1996, where the frequency is 1MHz; ‧Loss tan: loss tangent, measured at 1MHz and 5V, measured at SJ / T 11043-1996, where the frequency is 1MHz; ‧ Young's modulus: single axis The ratio of stress to linear strain is measured by the ASTM E1876 response method; ‧ Pusson ratio: the ratio of the transverse set shrinkage strain to the longitudinal extension strain in the direction of tensile force is measured by the ASTM E1876 response method; ‧ shear modulus: The ratio of shear stress to shear strain is measured by the ASTM E1876 response method; ‧CS: compressive stress after chemical strengthening at 450 ° C for 8 hours (prone to coplanar stress of atoms in the compression surface); ‧DOL: layer depth , Which represents the compression depth below the surface to the closest zero-stress plane after chemical strengthening at 450 ° C for 8 hours; and ‧CT: central tension after chemical strengthening at 450 ° C for 8 hours.

Although the present invention is described with some specific embodiments, those skilled in the art will understand that the present invention can be implemented and implemented within the spirit and scope of the scope of the attached patent.

All reference terms in space, such as "up", "down", "up", "down", "between", "bottom", "vertical", "horizontal", "tilt", "up", " Down "," Adjacent "," Left to Right "," Left "," Right "," Right to Left "," Top to Bottom "," Bottom to Top "," Top "," Bottom "," "Bottom up", "Top down", etc. are for illustration purposes only, and do not limit the specific orientation or position of the above structure.

The invention has been described in terms of specific embodiments. Those skilled in the art will clearly understand that the improvements or modifications fall within the spirit and scope of the present invention after reading the disclosed content. It should be understood that several modified examples, variations and alternatives are included in the foregoing disclosure, and in some cases, some features of the present invention may be applied without corresponding use of other features. Therefore, it is appropriate to interpret the scope of the attached application patent broadly and to interpret it in a manner consistent with the scope of the present invention.

Claims (8)

A chemically strengthened alkali aluminum borosilicate glass made of a glass composition, comprising: about 60.0 to about 70.0 mol% of SiO ₂ ; about 6.0 to about 10.0 mol% of Al ₂ O ₃ ; about 5.0 to about 10.0 mol% Na ₂ O; about 15.0 to about 25.0 mol% B ₂ O ₃ ; about 0 to about 5.0 mol% K ₂ O; and about 0 to about 3.0 mol% MgO; wherein the glass has about 5.0 to A dielectric constant of about 6.5; and the glass composition is ion-exchanged, and has a surface compressive stress layer and a central tension region; the glass has a density of less than 2.3 g / cm ³ ; the glass has 53.0 Coefficient of linear expansion to one of 70.0 (α _25-300 10 ^-7 / ° C). The chemically strengthened alkali-aluminum-borosilicate glass according to item 1 of the patent application scope, wherein the surface compressive stress layer has a compressive stress of about 100 MPa to about 250 MPa. The chemically strengthened alkali-aluminum-borosilicate glass according to item 1 of the patent application scope, wherein the depth of the surface compressive stress layer is about 15.0 μm to about 35.0 μm. A method for manufacturing a chemically strengthened alkali aluminum borosilicate glass, comprising: mixing and melting glass raw material components to form a homogeneous glass melt, comprising: about 60.0 to about 70.0 mol% SiO ₂ ; about 6.0 To about 10.0 mol% of Al ₂ O ₃ ; about 5.0 to about 10.0 mol% of Na ₂ O; about 15.0 to about 25.0 mol% of B ₂ O ₃ ; about 0 to about 5.0 mol% of K ₂ O; and about 0 to about 3.0 mol% MgO; forming the glass using a method selected from the overflow down-draw method, the floating method, and a combination thereof; annealing the glass; and by ionizing at a temperature of about 390 ° C to about 450 ° C The glass is chemically strengthened by exchanging for 2 to 24 hours; the glass has a density below 2.3 g / cm ³ ; the glass has a linear expansion coefficient (α _25-300 10 ^-7 / ° C) of 53.0 to 70.0. The method according to item 4 of the scope of patent application, wherein the glass raw material component is melted at a temperature of about 450 ° C for about 8 hours. The method as described in item 4 of the patent application range, wherein the glass is annealed at a rate of about 0.5 ° C / hour. The method as described in claim 4 of the patent application, wherein the glass is chemically strengthened by ion exchange in a molten salt bath. The method according to item 7 of the scope of patent application, wherein the molten salt is KNO ₃ .