Low-aluminum high-boron-silicon fireproof luminescent glass and preparation process thereof

Abstract

This invention discloses a low-aluminum, high-borosilicate fire-resistant luminescent glass and its preparation process, belonging to the field of glass technology. The technical solution comprises the following components in parts by weight: SiO₂ 2 65-75 parts, B2O3 10-16 parts, Al2O 3 2-3 parts, CaO 1-2 parts, MgO 1-2.5 parts, Na₂O 3-7 parts, K₂O 1-3.5 parts, TiO₂ 2 0.5-2 parts, Eu2O 3 4-7 parts of Ag, 0.5-1.0 parts of NaCl, and 0.5-1.5 parts of NaCl. The low-alumina, high-borosilicate fire-resistant luminescent glass prepared by this invention has excellent optical properties, high transmittance, high mechanical strength, excellent chemical corrosion resistance, high softening point and luminous intensity, low coefficient of thermal expansion, and excellent fire resistance, and has good application prospects.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of glass, in particular to a low-aluminum high-borosilicon fireproof luminescent glass and a preparation process thereof. BACKGROUND

[0002] From the birth of the world's first touch sensor in 1971 to today, touch screens, as the most commonly used and simplest communication interface of today's smart mobile terminals, have been favored by the majority of consumers for their convenient use and have penetrated into various aspects of people's daily life. Cover glass, as an important structural material for protecting touch screens, has also gradually become a research hotspot. According to the composition of the glass, the glass can be divided into three types: sodium calcium silicate glass, alkali alumino-silicate glass and borosilicate glass.

[0003] In the field of smart mobile terminals, high-aluminum content alkali alumino-silicate glass, as the best chemically tempered cover glass in today's glass, is the most widely used glass in the world and is widely used in mobile phones, computers, digital cameras and optical lenses, etc. For example, Chinese patent CN116282909A discloses a high-alumina silicate glass and its preparation method and application. The components of the high-alumina silicate glass include: 58%-63% of SiO2, 16%-20% of Al2O3, 12%-16% of Na2O, 2%-5% of K2O, 2%-5% of MgO, 0.5%-1.5% of ZrO2 and 1%-3% of B2O3. However, due to the high content of Al2O3 and SiO2 in this glass, the high-temperature viscosity and surface tension of the glass melt are large, which adversely affects the melting, clarification and forming processes in the float production process. Therefore, it is currently an urgent need to research and prepare high-quality low-alumina silicate glass that can be applied to the industrial production process level. SUMMARY

[0004] The technical problem to be solved by the present application is to overcome the shortcomings of the prior art and provide a low-aluminum high-borosilicon fireproof luminescent glass and a preparation process thereof. The prepared low-aluminum high-borosilicon fireproof luminescent glass has excellent optical performance, high transmittance, high mechanical strength, excellent chemical corrosion resistance, high softening point and luminescent intensity, low thermal expansion coefficient and excellent fireproof performance, and has good application prospects.

[0005] The technical scheme of the present application is as follows:

[0006] In one aspect, the present application provides a low-aluminum high-boron-silicon fireproof luminescent glass, comprising the following components in parts by weight: SiO2 65-75 parts, B2O3 10-16 parts, Al2O3 2-3 parts, CaO 1-2 parts, MgO 1-2.5 parts, Na2O 3-7 parts, K2O 1-3.5 parts, TiO2 0.5-2 parts, Eu2O3 4-7 parts, Ag 0.5-1.0 parts, NaCl 0.5-1.5 parts.

[0007] Preferably, the following components in parts by weight are included: SiO2 67 parts, B2O3 14 parts, Al2O3 2 parts, CaO 1.4 parts, MgO 1.8 parts, Na2O 5 parts, K2O 1.8 parts, TiO2 1 part, Eu2O3 4.8 parts, Ag 0.6 parts, NaCl 0.6 parts.

[0008] SiO2 in the glass as a glass former in the structure of [SiO4] tetrahedron, the content of SiO2 has a crucial impact on both the degree of polymerization of the glass network and the type of short-range ordered structure. The role of introducing SiO2 is to improve the melting temperature, viscosity, chemical stability, thermal stability and mechanical strength of the glass, while it can also reduce the thermal expansion coefficient and density of the glass.

[0009] In the present application, a small amount of Al2O3 is contained, which can capture the oxygen provided by Na2O to form [AlO4] tetrahedron, which can replace [SiO4] tetrahedron in the glass to form a unified three-dimensional network structure. Since Al2O3 replaces part of SiO2 to connect non-bridge oxygen, thereby closing the path between the holes, which hinders the phase separation and crystallization caused by the aggregation of Na2O and B2O3. At the same time, adding a small amount of Al2O3 can also improve the chemical stability of the glass, making the working temperature range larger, which is beneficial to the forming operation; but if too much Al2O3 is added, it will affect the formation of [BO4] tetrahedron, because [AlO4] is more stable than [BO4] tetrahedron, when the content of introduced Al2O3 is too high, it will be difficult for [BO4] tetrahedron to form, and boron will exist in the form of [BO3] triangle in the glass network, thereby leading to the decrease of glass stability and mechanical properties; on the other hand, when the content of Al2O3 is too low, the activation energy of viscosity is increased, the softening temperature is reduced, and the melting process becomes difficult, so it is appropriate to control the content of Al2O3. In addition, because Eu2O3 is prone to agglomeration in borosilicate glass, the addition of Al2O3 can improve the solubility of rare earth ions Eu 3+ in Eu2O3, because Eu2O3 and Al2O3 have similar structures, the oxygen around Al 3+ can act as a charge compensator for rare earth ions, so that the rare earth ions Eu 3+ are uniformly dispersed in the glass matrix, effectively improving the luminescent performance of the glass.3+ luminescent efficiency.

[0010] B2O3 exists in two forms in glass, boron oxygen tetrahedron and boron oxygen triangle, the boron oxygen tetrahedron is a framework structure, which can combine with the silicon oxygen tetrahedron in the glass to strengthen the glass network structure; the boron oxygen triangle is a layer structure, which makes the glass structure more loose. B2O3 can reduce the viscosity of the glass at high temperature, and increase the viscosity of the glass at low temperature, so the glass containing a high content of B2O3 has a narrow forming temperature range in the process, which can improve the speed of rapid forming of the glass. In addition, B2O3 also plays a role of a dissolving agent, which can accelerate the clarification of the glass and reduce the crystallization ability of the glass. In addition, the addition of B2O3 can make part of Eu 3+ transform into Eu 2+ , which means that there is a microstructure in the glass matrix of the present application that can make the rare earth ions self-reduce and promote the occurrence of the self-reduction process, and with the increase of the network former component, the self-reduction ability is stronger, which can change the glass structure and affect the luminescent performance of the glass. The addition of B2O3 is more conducive to the existence of the existence state of Ag with a low aggregation degree or a free state, which can make Ag better cover the surface of the glass in the low-temperature ion exchange process, so as to enhance the luminescent performance of the glass.

[0011] CaO is a non-variable glass structure network outer oxide, which mainly plays a role of a stabilizer, and the addition of CaO can reduce the viscosity of the glass, that is, increase the chemical stability and mechanical properties of the glass.

[0012] MgO is a glass structure network outer oxide, and can make large tetrahedrons depolymerize, thereby reducing the viscosity of the glass.

[0013] Na2O is a glass network outer oxide, and Na 2+ is located in the hole of the glass structure. Na2O can provide free oxygen to increase the O / Si ratio in the glass structure, break the bond, thereby reducing the viscosity of the glass, making the glass easy to melt, and being a good dissolving agent for the glass. The addition of Na2O will change the structure of boron, because Na2O provides free oxygen, which makes [BO3] transform into [BO4], and the structure of boron changes from a layer to a framework. With the increase of the content of Na2O, the content of [BO3] transforming into [BO4] will also become larger, and the charge load of [BO4] cannot be directly connected, one [BO4] can only be connected through four [BO3] to form a [BO4]-4[BO3] structure. [BO4] can also be connected with [SiO4] to form a BO4[SiO4]4 structure, which connects the broken silicon oxygen bond, enhances the strength of the structure bond, and improves the mechanical strength of the glass.

[0014] K 2+ in K2O has a larger radius than Na 2+The radius, field intensity is small, and the binding force with oxygen is weak, so the free oxygen ability given by K2O is larger than that of Na2O, thus K2O reduces the viscosity of the glass more than Na2O, and can reduce the crystallization tendency of the glass, increase the transparency and gloss of the glass, and has the advantages of lower surface tension and slower hardening speed.

[0015] The gloss of the glass is related to the refractive index, and the larger the refractive index, the stronger the gloss. TiO2 is the main component for enhancing the refractive index, and thus improving the gloss of the glass. TiO2 itself has high chemical stability to water, acid and alkali; in addition, TiO2 can enter the glass network structure, and is also relatively stable with SiO2 as the glass network structure. In the erosion process, K 2+ The diffusion and exchange of ions are controlled, and the network structure of the glass is not destroyed. The glass of the present application contains alkali metal Na2O, K2O oxide, which can make Ti 4+ Enter the network as [TiO4] to form stable glass with [SiO4]. This structure-stable glass has high chemical stability.

[0016] The luminescence of Eu2O3 is generated in the transition process between different energy levels of 4f layer electrons of rare earth ions in the ground state or low excitation state. The rare earth ions in the ground state or low excitation state absorb energy and transition to the excited state under external excitation. When the 4f layer electrons transition from the excited state to the ground state, different wavelengths of light are emitted. The glass system of the present application belongs to the borosilicate glass system, which has high transmittance, low synthesis temperature, high solubility of rare earth ions, low glass expansion coefficient, and relatively cheap raw materials, thereby saving cost.

[0017] The noble metal Ag can achieve good doping effect in the glass material and has stable properties, which mainly affects the luminescence of the rare earth ion Eu 3+ . Because when Ag is doped in the glass matrix, the aggregation effect of Ag is easy to occur, the Ag particles and the conductive electrons are excited together, thereby a strong electromagnetic field is generated in the glass structure, the excitation efficiency of the adjacent rare earth ion Eu 3+ is greatly enhanced, and thus the absorption efficiency of the rare earth ion Eu 3+ to the photons is improved, and the luminescence is also enhanced. In the structure system of the glass of the present application, there are two kinds of coordination structures of [BO3] and [BO4] in the glass network, and structural changes such as boron anomaly, and there are complex structures of different aggregation states such as diboric acid ring, triboric ring, tetraboric ring, pentaboric ring formed by the connection of [BO3] and [BO4], which can enhance the fireproof performance of the glass.

[0018] The noble metal Ag can accelerate the ion exchange of Ag + -Na +The exchange causes the silver clusters to form on the surface of the glass and makes the non-bridge oxygen and Si recombine, and the reaction is as follows. The volume fraction of the silver clusters in the glass matrix increases, leading to the enhancement of the surface plasmon resonance absorption, which can enhance the fireproof performance.

[0019] ≡S-O-Na+Ag + →≡S-O-Ag+Na +

[0020] 2≡S-O-Ag→≡S-O-Ag-O-Si+Ag 0

[0021] NaCl is a good high-temperature fining agent for glasses with a melting temperature higher than 1500℃, which can significantly reduce the surface tension of the glass and improve the mechanical strength of the glass. At high temperatures, NaCl gasifies and volatilizes, and the NaCl vapor diffuses upward into the gas bubbles in the glass liquid, causing the gas bubbles to expand and rise, and then escape, which is beneficial to promoting the fining and homogenization of the glass.

[0022] In another aspect, the application provides a preparation process of the above-mentioned low-aluminum high-borosilicon fireproof luminescent glass. The glass liquid flows from the tail of a melting furnace to the surface of a molten tin liquid through a flow channel, and under the action of gravity and surface tension, the glass liquid spreads to become a glass ribbon, which is drawn to the tail of the tin channel, polished, thinned, hardened, and cooled, and then drawn onto a transition roller table. The transition roller table draws the glass ribbon out of the tin channel and sends it into an annealing furnace for annealing to obtain a raw sheet glass. After inspection, cutting, edge grinding, washing and drying, the raw sheet glass is subjected to ion exchange. The process of ion exchange is as follows: the temperature of the glass is raised from room temperature to 350-380℃ for preheating within 60-90min, and the preheating holding time is 10-15min; after preheating, the temperature is continuously raised to 400-430℃ for raw sheet glass strengthening, the strengthening time is 190-260min, and the strengthening holding time is 5min. At the same time of holding, salt dripping operation is performed, which replaces the Na + with a relatively small ion radius in the glass with ions with a larger radius in the molten salt, causing a surface compressive stress layer due to the volume difference between the ions, to improve the strength of the glass; after strengthening, the temperature is lowered to 320-350℃ for annealing, the annealing time is 150-170min, and then the temperature is continuously lowered to 10-30℃, and the annealing is completed, to obtain the finished glass.

[0023] Preferably, the salt dripping operation is as follows: after the glass is held for 5min, it is immersed in a molten salt filled with KNO3 for ion exchange, and the time is 190-260min; then the glass is raised above the toughening furnace, and the salt dripping operation is performed for 10-20min, so that the molten salt on the glass slowly drips into the toughening furnace.

[0024] Compared with the prior art, the application has the following beneficial effects:

[0025] 1. The low-aluminum high-boron-silicon fireproof luminescent glass prepared by the present application has excellent optical performance, high transmittance, high mechanical strength, excellent chemical corrosion resistance, high softening point and luminescent intensity, low thermal expansion coefficient and excellent fireproof performance, and has good application prospect.

[0026] 2. The low-aluminum high-boron-silicon fireproof luminescent glass prepared by the present application has excellent optical performance, high transmittance, high mechanical strength, excellent chemical corrosion resistance, high softening point and luminescent intensity, low thermal expansion coefficient and excellent fireproof performance, and has good application prospect. DETAILED DESCRIPTION

[0027] In order to make the person skilled in the art better understand the technical solutions in the present application, the technical solutions of the present application will be described clearly and completely below in combination with the embodiments of the present application.

[0028] Examples 1-5 and Comparative Examples 1-5

[0029] The 2.5mm thick low-aluminum high-boron-silicon fireproof luminescent glass of Examples 1-5 and Comparative Examples 1-5 is shown in Table 1-2:

[0030] Table 1 Low-aluminum high-boron-silicon fireproof luminescent glass of Examples 1-5

[0031]

[0032] Table 2 Low-aluminum high-boron-silicon fireproof luminescent glass of Comparative Examples 1-5

[0033]

[0034] The forming process of the float production is completed in a tin bath into which a protective gas (N2 and H2) is introduced. The glass is melted and refined at a high temperature of 1500-1650℃, and the obtained glass liquid is continuously flowed from the pool kiln and floated on the surface of the tin liquid with a large relative density. Under the action of gravity and surface tension, the glass liquid is spread and flattened on the tin liquid surface at a temperature of 1200-1300℃, forming a glass ribbon with a flat lower surface and parallel to each other. The glass ribbon is drawn to the tail of the tin bath, polished, thinned, hardened, cooled, introduced into the transition roller table, and annealed at a temperature of 600-650℃ to obtain the original glass sheet. The parameter settings of each process in Examples 1-5 are shown in Table 3, and the parameter settings of Comparative Examples 1-5 are the same as those of Example 1.

[0035] Table 3 Parameter settings of each process in the float production of Examples 1-5

[0036]

[0037] After the original sheet glass is inspected, cut, ground, washed and dried, low-temperature ion exchange is performed. The process of low-temperature ion exchange is as follows: the temperature of the glass is raised from room temperature to 350-380°C for preheating within 60-90 min, and the preheating time is 10-15 min; after preheating, the temperature is continuously raised to 400-430°C for original sheet glass strengthening, the strengthening time is 190-260 min, and the strengthening time is 5 min. At the same time, salt dripping is performed: after the glass is strengthened for 5 min, the glass is immersed in a molten salt filled with KNO3, and ion exchange is performed for 190-260 min; then the glass is slowly raised to the upper side of the strengthening furnace, and salt dripping is performed for 10-20 min, so that the molten salt on the glass slowly drips into the strengthening furnace; after strengthening, the temperature is lowered to 320-350°C for annealing, the annealing time is 150-170 min, then the temperature is continuously lowered to 10-30°C, and annealing is completed, thereby obtaining finished glass. The parameter settings of each process in Examples 1-5 are shown in Table 4, and the parameter settings of Comparative Examples 1-5 are the same as those of Example 1.

[0038] Table 4 Parameter settings of each process in low-temperature ion exchange of Examples 1-5

[0039]

[0040] The measurement method of the coefficient of thermal expansion of the glass prepared in Examples 1-5 and Comparative Examples 1-5 is as follows: the testing instrument is a German NETZSCH DIL 402C dilatometer, the heating rate is 5°C / min, and the heating temperature range is 0-1200°C; the annealed glass sample is cut into a square with a cross section of 4 mm x 4 mm on an inner diameter cutting machine, and then ground into a small rectangular column with a length of 40-45 mm. The thermal expansion curve of the sample is measured on the dilatometer at a heating rate of 5°C / min; the transition temperature (Tg) and the expansion softening temperature (Tf) of the glass can be obtained from the inflection point on the expansion curve, and the coefficient of thermal expansion is calculated by the formula: a = (L2-L1) / L0 x (T2-T1) + a (reference).

[0041] wherein: a - the average linear expansion coefficient of the sample in the range of T1-T2, 10 -6 / ℃; (L2-L1) - the length difference of the sample after expansion between two temperatures, mm; L0 - the initial length of the sample, mm; a (reference) - the linear expansion coefficient of quartz glass, which is 5.7 x 10 -7 / ℃.

[0042] Method for measuring softening temperature of the glasses prepared in Examples 1-5 and Comparative Examples 1-5: the softening temperature of the glasses was measured by using a wire drawing method, and the testing instrument was a DNY type hanging wire method glass fixed point viscosity tester; the length of the glass wire was 235±1 mm, and the average diameter was 0.65 mm±0.10 mm, which was hung in the furnace of the testing instrument and heated at a speed of 5 ℃ / min, and the temperature at which the glass wire was elongated by 1 mm per minute under the action of its own gravity was defined as the softening temperature of the glass, which is also commonly known as the Littleton point, and the corresponding viscosity was about 10 6.6 Pa·S.

[0043] Method for measuring visible light transmittance of the glasses prepared in Examples 1-5 and Comparative Examples 1-5: the visible light transmittance of the 50 mm×20 mm×2.5 mm glass at a wavelength of 510 mm was measured by using a Shimadzu UV-2600i type ultraviolet-visible spectrophotometer.

[0044] Method for measuring gloss of the glasses prepared in Examples 1-5 and Comparative Examples 1-5: according to international standards and national standards, the WYY-1 type digital gloss meter was used for testing, the instrument measurement range was 0-199.9, the graduation value was 0.1, and the indication error was ±1.

[0045] Method for measuring chemical properties of the glasses prepared in Examples 1-5 and Comparative Examples 1-5: the glass is subjected to erosion by water, acid and alkali during use, and the resistance of the glass to these erosions is called chemical stability; the stronger the erosion resistance of the glass, the better the chemical stability; the water resistance test was carried out by using a powder method; and the acid and alkali resistance test was carried out by using a surface method.

[0046] Method for measuring water resistance of the glasses prepared in Examples 1-5 and Comparative Examples 1-5: the water resistance test of the glass was carried out according to the method specified in GB / T6584-1997 (granular test method and classification of water resistance of glass at 98 ℃), 2 g of glass powder with a particle size of 300-500 um was heated with 50 mL of water in a boiling water bath for 2 h, the separated alkali was titrated with hydrochloric acid, the concentration of HCl was 0.1 mol / L, methyl red was used as an indicator, and the water resistance grade was determined according to the acid consumption, and the water resistance grade classification is shown in Table 5:

[0047] Table 5 Classification of water resistance grade of glass

[0048]

[0049] Method for measuring acid resistance of the glasses prepared in Examples 1-5 and Comparative Examples 1-5: the acid resistance test of the glass was carried out according to the method specified in GB / T015728-1995 (weight test method and classification of glass resistance to boiling hydrochloric acid erosion), the glass was cut into a shape easy to measure, and the total surface area was 10-15 cm 2Two samples were tested, and the glass surfaces were boiled in 6 mol / L hydrochloric acid for 6 hours, with a concentration of mg / 100cm³. 2 The weight loss of the glass was determined, and the glass was classified into four acid resistance grades based on its average value. The acid resistance grade classification is shown in Table 6.

[0050] Table 6 Classification of Glass Acid Resistance Grades

[0051]

[0052] Methods for determining the alkali resistance of the glasses prepared in Examples 1-5 and Comparative Examples 1-5: The alkali resistance of the glass was tested according to the method specified in GB / T 6580-1997 (Test method and classification of glass resistance to erosion by boiling mixed alkaline aqueous solution). The glass was cut into easily measurable shapes with a total surface area of ​​10-15 cm². 2 Two samples were tested, and the glass surfaces were boiled for 3 hours in a mixed solution of equal volumes of NaOH (1 mol / L) and NaCO3 (0.5 mol / L). The concentration of the tested samples was determined by the concentration of NaOH and NaCO3 at a concentration of mg / 100 cm³. 2 The weight loss of the glass was determined, and the average value was used to classify the glass into three alkali resistance grades, as shown in Table 7.

[0053] Table 7 Classification of Alkali Resistance Grades of Glass

[0054]

[0055] Methods for determining the flexural strength of the glasses prepared in Examples 1-5 and Comparative Examples 1-5: The mechanical strength of the glass is measured by its flexural strength. A KJJ300-1 electric flexural strength tester was used, with a maximum load of 300 N and an accuracy of 1%. The sample size was 50 mm × 4 mm × 2.5 mm. The calculation formula was: K = 3PL / 2BH 2 The flexural strength data is the average value of 10 test specimens.

[0056] Where: K – flexural strength, MPa; P – failure load, N; L – span, mm; B – cross-sectional width, mm; H – cross-sectional thickness, mm.

[0057] Methods for determining the impact strength of the glass prepared in Examples 1-5 and Comparative Examples 1-5: Impact strength is one of the main indicators for measuring the mechanical strength of glass products. The test method is to lift a 1040g solid steel ball to a certain height and let it fall freely, with the landing point within a 25mm diameter range of the center point of the sample. Rubber rings are used to pad the glass and the support. If it does not break on the first try, it is lifted to a certain height and the impact is continued until the sample breaks. The height at this point is the impact strength of the glass.

[0058] The method for measuring the microhardness of the glasses prepared in Examples 1-5 and Comparative Examples 1-5 is as follows: the glass sample is cut into a 2.5 mm thick glass sheet, washed with clean water and dried, and polished to smooth the surface for observing the length of the indentation; the hardness of the glass is measured on a HVS-1000 digital microhardness tester, the sample surface is pressed for 15 s, and then the length of the diagonal of the indentation is observed; the length of the indentation is measured for at least 3 groups, and the average value is taken; the calculation formula is: Hv = 1854 · P / 9.81 · I 2 .

[0059] In the formula, Hv is the microhardness, MPa; I is the average value of the length of the diagonal of the indentation, mm; and P is the load = 0.1 kgf.

[0060] The method for measuring the fire resistance of the glasses prepared in Examples 1-5 and Comparative Examples 1-5 is as follows: the national current standard (GB / T-12512-2001) is referred to, and the measurement is carried out in a fire resistance furnace; the glass has a size of 700 mm x 500 mm, and the fire resistance time of the glass at 800°C is measured.

[0061] The performance test results of the 2.5 mm thick low-aluminum high-borosilicate fireproof luminescent glass prepared in Examples 1-5 and Comparative Examples 1-5 are shown in Tables 8-9:

[0062] Table 8 Performance test results of the glass of Examples 1-5

[0063]

[0064] Table 9 Performance test results of the glass of Comparative Examples 1-9

[0065]

[0066] Compared with Example 1, the stability and mechanical properties of the glass prepared in Comparative Example 1 are reduced, mainly because when the content of Al2O3 in the glass batch is too high, it is difficult to form [BO4] tetrahedron, and boron exists in the form of [BO3] triangle in the glass network, thereby reducing the stability and mechanical properties of the glass.

[0067] Compared with Example 1, the optical properties and softening temperature of the glass prepared in Comparative Example 2 are reduced, mainly because Al 3+ The electric charge is high, the ionic radius is small, and the force is huge, so that the glass melt tends to form more complex polyatomic anion groups, thereby increasing the viscous activation energy, reducing the softening temperature, and making the melting process difficult.

[0068] Compared with Example 1, the optical properties of the glass prepared in Comparative Example 3 are reduced, mainly because the addition of Al2O3 in Example 1 can increase the content of rare earth ions Eu 3+solubility. Because Eu2O3 has similar structure with Al2O3, Al 3+ The oxygen around can be as charge compensator of rare earth ions, so that the rare earth ions Eu 3+ are uniformly dispersed in the glass matrix, effectively improving the luminescent efficiency of the rare earth ions Eu 3+ .

[0069] Compared with Example 1, the optical properties of the glass prepared in Comparative Example 4 are decreased, mainly because the ability of K2O to give free oxygen is greater than that of Na2O in Example 1, so the viscosity of the glass is reduced more by K2O than by Na2O, and the tendency of the glass to crystallize is reduced, thereby increasing the light transmittance and gloss of the glass.

[0070] Compared with Example 1, the chemical stability of the glass prepared in Comparative Example 5 is decreased, mainly because TiO2 itself has high chemical stability to water, acid and alkali; in addition, TiO2 can enter the glass network structure and is relatively stable with SiO2 as the glass network structure, so the diffusion and exchange of K 2+ ions are controlled and the network structure of the glass is not destroyed. In Example 1, the alkali metal Na2O and K2O oxides can make Ti 4+ enter the network as [TiO4] to form stable glass with [SiO4], and such a structure-stable glass helps to improve the chemical stability.

[0071] Compared with Example 1, the thermal properties and gloss of the glass prepared in Comparative Example 6 are decreased, mainly because the rare earth ions Eu 3+ in Eu2O3 have rich electronic energy levels and special electronic layer structure. There are unfilled 4f holes in the electronic layer structure of the rare earth ions Eu 3+ , resulting in multiple energy levels, so that the 4f electrons absorb or emit energy at different energy levels. When the 4f electrons jump from a high energy level to a low energy level by radiation, different wavelengths of light are emitted, so that the glass is affected by the rare earth activated ions and emits light of different wavelengths, thereby enhancing the gloss of the glass.

[0072] Compared with Example 1, the fireproof performance of the glass prepared in Comparative Example 7 is greatly decreased, mainly because the noble metal Ag accelerates the Ag + -Na + exchange during ion exchange heat treatment of the original glass sheet, causing the formation of silver clusters on the surface and the re-bonding of non-bridging oxygen and Si; because the volume fraction of the silver clusters in the glass matrix increases, the surface plasmon resonance absorption is enhanced, thereby enhancing the fireproof performance.

[0073] Compared with Example 1, the mechanical strength of the glass prepared in Comparative Example 8 is greatly reduced, mainly because NaCl is a good high-temperature fining agent, which can significantly reduce the surface tension of the glass and increase the mechanical strength of the glass when used in the glass with a melting temperature higher than 1500℃.

[0074] Compared with Example 1, the optical performance of the glass prepared in Comparative Example 9 is greatly reduced, mainly because the addition of B2O3 causes part of Eu 3+ to be converted into Eu 2+ , which means that there is a microstructure in the glass matrix that can cause self-reduction of rare earth ions and promote the occurrence of the self-reduction process, and with the increase of the network former component, the self-reduction ability is stronger, which can change the glass structure and affect the luminescent performance of the glass. Moreover, the addition of B2O3 is more conducive to the existence of the existence state of Ag with low aggregation degree or free state, so that the luminescent performance of the glass is excellent.

[0075] Comparative Examples 10-11

[0076] The difference between Example 1 and Comparative Examples 10 and 11 is that the rare earth oxide Eu2O3 in Example 1 is replaced by La2O3 and Y2O3 respectively.

[0077] The 2.5mm-thick low-aluminum high-borosilicate fireproof luminescent glass prepared in Comparative Examples 10-11 is tested for performance, and the test results are shown in Table 10:

[0078] Table 10 Glass performance test results of Comparative Examples 10-11

[0079]

[0080] Compared with Example 1, the optical performance of the glass prepared in Comparative Example 10 is reduced, mainly because the rare earth element La in La2O3 destroys the Si-O bond and Si-O2 bond, causing them to break, which slightly reduces the chemical strength of the glass; La2O3 can promote the conversion of [AlO4] structural units to [AlO6] structural units, and [AlO6] structural units can act as a network modifier in the network structure of the glass, which can reduce the accumulation of the glass and reduce the gloss.

[0081] Compared with Example 1, the optical performance and fire resistance of the glass prepared in Comparative Example 11 are reduced, mainly because the radius of Y 3+ ions in Y2O3 is smaller than the ionic radius of Si 4+ , SiO2 reacts with Y2O3, which can reduce the molecular volume of the glass matrix, reduce the fire resistance of the glass, and at the same time increase the number of rare earth ions, reduce the number of silver ions, cause the content of silver ions to decrease sharply in the glass system, and make the glass basically have no luminescent performance.

[0082] Comparative Example 12

[0083] The difference from Example 1 is that Comparative Example 12 replaces the low-temperature ion exchange process with a high-temperature ion exchange method: the original glass sheet is placed in lithium nitrate molten salt at 700°C, so that the Na on the glass surface... + With Li, which has a smaller radius than them + Exchange for 250 minutes, then cool to room temperature.

[0084] Comparative Example 13

[0085] The difference from Example 1 is that Comparative Example 13 does not perform low-temperature ion exchange strengthening treatment on the original glass.

[0086] The performance of the 2.5 mm thick low-aluminum high-borosilicate fire-resistant luminescent glass prepared in Comparative Examples 12-13 was tested, and the test results are shown in Table 11:

[0087] Table 11 Test results of glass properties in Comparative Examples 12-13

[0088]

[0089] Compared to Example 1, the optical properties of the glass prepared in Comparative Example 12 decreased significantly, mainly due to the loss of Li in the high-temperature molten salt during the high-temperature ion exchange process. + Unable to remove Ag from the glass + The displacement prevents the formation of silver clusters on the glass surface, thus preventing the excitation of rare earth ions (Eu). 3+ Therefore, it is impossible to increase the rare earth ion Eu. 3+ Its absorption efficiency of photons makes it non-luminescent.

[0090] Compared with Example 1, the mechanical strength of the glass prepared in Comparative Example 13 was significantly reduced. This is mainly because strengthening the glass by low-temperature ion exchange increases the internal stress of the glass, strengthens the chemical bonds, and thus improves its mechanical strength.

[0091] The above experiments show that the low-aluminum, high-borosilicate fire-resistant luminescent glass prepared by this invention has excellent performance, including excellent optical properties, high transmittance, high mechanical strength, excellent chemical corrosion resistance, high softening point and luminous intensity, low coefficient of thermal expansion, and excellent fire resistance, and has good application prospects.

Claims

1. A low-aluminum, high-borosilicate fire-resistant and luminescent glass, characterized in that: The composition includes the following components in parts by weight: SiO2 65-75 parts, B2O3 10-16 parts, Al2O3 2-3 parts, CaO 1-2 parts, MgO 1-2.5 parts, Na2O 3-7 parts, K2O 1-3.5 parts, TiO2 0.5-2 parts, Eu2O3 4-7 parts, Ag 0.5-1.0 parts, and NaCl 0.5-1.5 parts; The manufacturing process of low-aluminum, high-borosilicate, fire-resistant, and luminescent glass: Molten glass flows from the tail of the melting furnace through a flow channel onto the surface of molten tin. The molten glass spreads into a glass ribbon, which is drawn towards the tail of the tin bath. After polishing, thinning, hardening, and cooling, it is guided onto a transition roller table. The transition roller table pulls the glass ribbon out of the tin bath and sends it to an annealing furnace for annealing, obtaining raw glass sheets. After inspection, cutting, edge grinding, washing, and drying, the raw glass sheets undergo ion exchange. The ion exchange process involves allowing the glass temperature to rise from room temperature within 60-90 minutes. Preheat the glass to 350-380℃ for 10-15 minutes. After preheating, continue heating to 400-430℃ for strengthening the original glass sheet for 190-260 minutes, followed by a 5-minute holding period. Simultaneously, perform salt dripping. After strengthening, cool to 320-350℃ for annealing for 150-170 minutes, then continue cooling to 10-30℃. Annealing is now complete, yielding the finished glass. The salt dripping operation is as follows: after being heated for 5 minutes, the glass is immersed in molten salt filled with KNO3 for ion exchange for 190-260 minutes; then the glass is raised above the tempering furnace and salt is dripped for 10-20 minutes, allowing the molten salt on the glass to drip slowly.

2. The low-aluminum, high-borosilicate fire-resistant luminescent glass as described in claim 1, characterized in that, The components include the following parts by weight: SiO2 67 parts, B2O3 14 parts, Al2O3 2 parts, CaO 1.4 parts, MgO 1.8 parts, Na2O 5 parts, K2O 1.8 parts, TiO2 1 part, Eu2O3 4.8 parts, Ag 0.6 parts, and NaCl 0.6 parts.

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